METHOD FOR PRODUCING A BIORESORBABLE TUBE BASED ON METHACRYLIZED GELATINE AND METHACRYLIZED FIBROIN AND A METHOD FOR RECONSTRUCTING A SMALL INTESTINE WALL EXPERIMENTALLY USING SUCH A TUBE Russian patent published in 2020 - IPC A61F2/02 A61F2/04 A61K38/17 A61K35/64 A61L27/22 

FIELD: biotechnology.

SUBSTANCE: invention relates to biotechnology and medicine. In more detail, the invention refers to surgery, regenerative medicine and tissue engineering, namely to methods of restoring walls of gastrointestinal ducts. Disclosed is a method of recovering the wall of the small intestine, involving the following steps: 1) obtaining a bioresorbable tube by implementing the following steps: a) dissolving in hexafluoroisopropanol of macromonomers: methacrylized gelatine (GMA) at rate of 10 wt% and methacrylized fibroin (FMA) in amount of 4 wt% at 55±5 °C for 18–36 hours; b) obtaining a mixture which includes equal parts of solutions of liquid-phase polymer and FMA, and a photoinitiator of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide based on 5 wt% by weight of macromonomers; c) preparing a guide for forming a tube by degreasing, followed by drying a surface of a glass rod with a circular cross-section of 2–15 cm in diameter; d) preparing the reinforcing thread by holding untwisted 8/0-4/0 silk thread in the mixture obtained in step b); e) forming the first layers of the bioresorbable tube on the guide by immersing it in the mixture obtained at step b) for 5–10 seconds with subsequent rotation and exposure of the obtained workpiece in the ultraviolet lamp light for at least 2 minutes; f) reinforcing the end sections of the tube by laying the thread in turns at distance of 2–5 mm from the ends of the formed tube to the workpiece obtained at step e); g) forming the outer layers of the bioresorbable tube by immersing the workpiece obtained at step f) into the mixture obtained at step b) for 5-10 seconds, followed by rotating and exposing the obtained tube in the ultraviolet lamp light for at least 2 minutes; h) processing the formed tube by holding in distilled water for 1–1.5 hours, followed by holding in 96 % ethanol for 12–18 hours and repeated holding in distilled water for 1–1.5 hours, treating internal surface of the formed tube with chloroform. Further, at step 2) preparing the bioresorbable tube for closing the anastomosis by incubating it in a sterile physiological solution for 15–30 minutes with multiple physiological saline replacement; 3) preoperative preparation of experimental animals by feeding 10 % glucose without restriction for 2 days; 4) closing the anastomosis with the tube, for which the animals are anesthetized, fixed in a position on the back, introducing ceftriaxone intramuscularly at dose of 100 mg/kg of body weight, forming an operating wound into which a small intestine segment is removed, after which a counter-incision intestinal opening is incised from a half-diameter of an intestinal tube, a bioresorbable tube is inserted into the intestinal lumen and fixed with a surgical suture, thereafter, an intestinal tube segment 3-10 mm long is removed at the implantation site and the cavity is layer-by-layer closed with intestine placement into the abdominal cavity; 5) postoperative care by daily injections of ceftriaxone in amount of 50 mg/kg of body weight for 4 days.

EFFECT: possibility of reducing postoperative complications to their complete absence and complete recovery of a circular defect of the small intestine wall.

17 cl, 3 ex, 7 dwg