Formation of peritoneal adhesions is common complication after abdominal and pelvic surgery. They bear a significant health problem with an influence to quality of life and health care expenses. Promising approach for their prevention is using of biodegradable barrier films for physical separation of peritoneal surfaces. In the present study, highly porous pectin‐based three‐dimensional (3D) scaffolds were obtained by freeze‐drying technique. Physico‐chemical properties of the formed materials, including their morphology, porosity, density, and stability, have been studied. The evaluation of their biocompatibility, biodegradation, and potential antiadhesion effect was studied by in vivo experiment. To reinforce the scaffolds structure and improve their stability in physiological solutions, pectin chains were cross‐linked with divalent cations. We determined optimal cross‐linking conditions, which allow obtaining scaffolds with desired biodegradation rate. These cross‐linked scaffolds fully dissolved within 8 days in the peritoneal cavity with low presence of complications and some antiadhesive effect. It has also been determined that mesenchymal stem cells from adipose tissue could effectively adhere to the scaffolds with preservation of their viability. Our results show that obtained materials can be suggested as mechanical scaffold for delivery of the stem cells culture to peritoneal surfaces as a part of complex antiadhesive barrier system.

ЭКСПЕРИМЕНТАЛЬНАЯ МОДЕЛЬ ПЕРИТОНЕАЛЬНЫХ СПАЕКУО «Белорусский государственный медицинский университет» 1 , ГУО «Белорусская медицинская академия последипломного образования» 2 , г. Минск, Республика БеларусьЦель. Разработать экспериментальную модель перитонеальных спаек, наиболее приближенную к клиническим условиям, простую в исполнении, с высокой частотой спайкообразования и небольшим ко-личеством осложнений.Материал и методы. Были выбраны несколько экспериментальных моделей с выделением трех групп: повреждение серозы слепой кишки (группа 1, n=6), энтеротомия подвздошной кишки с последу-ющим ушиванием дефекта (группа 2, n=8), моделирование по собственной методике, заключавшейся в иссечении брюшины на контрлатеральных сторонах брюшной стенки (группа 3, n=22). Группу 3 разделили на 2 подгруппы: с и без инфицирования брюшной полости.Результаты. У животных первой группы спаечный процесс не развился ни у одной из 6 крыс. В дальнейшем от указанной модели отказались. Вскрытие просвета кишечника и его ушивание (группа 2) во всех случаях привело к формированию спаечного процесса, который, однако, был вариабельно расположен в брюшной полости. В двух случаях развилась несостоятельность швов на кишке. Кроме того, время опе-рации было наибольшим и составило 17 минут по сравнению с 7 минутами в первой группе и 5 минутами в третьей группе. Иссечение париетальной брюшины с инфицированием (3а подгруппа) характеризовалось большим количеством осложнений с образованием внутрибрюшных абсцессов и инфильтратов, высокой летальностью и чрезмерной выраженностью спаечного процесса, выходящего за пределы моделирования. Иссечение брюшины боковой стенки живота по собственной методике без инфицирования (подгруппа 3б) привело к спайкообразованию в 75% случаев с локализацией спаек только в областях моделирования, без развития послеоперационных осложнений и летальности.Заключение. Разработанная модель перитонеальных спаек приводит к спайкообразованию в боль-шом проценте случаев, имеет минимальное количество осложнений, отличается простотой выполнения и может быть рекомендована для изучения спаечного процесса. Ключевые слова: перитонеальные спайки, хирургическое лечение, экспериментальная модель, поврежде-ние брюшины, перитонит, заболеваемость, летальностьObjectives. To develop an experimental model of peritoneal adhesions that is close to clinical practice, simple to implement, with a high incidence of adhesions and small number of complications.Methods. Several experimental models were chosen with singling out three groups: injury of cecum serosa (group 1, n=6), ileum enterotomy with subsequent suturing of the defect (group 2, n=8), and model made by the authors, including the excision of the peritoneum on the contralateral sides of the abdominal wall (group 3, n=22). Third group was divided into two subgroups -with and without bacterial contamination of the peritoneal cavity.Results. There were no abdominal adhesions in animals of the first group. In future this model was abandoned. Opening of the intestinal lumen and its suturing (group 2) in...

Implant-related infection is one of the serious problems in regenerative medicine.Promising approach to overcome the problems caused by bacterial growth on the medical implants is their modification by bioactive coatings. A versatile technique for designing multilayer films with tailored characteristics at the nanometer scale is layer-by-layer assembly. In this study, multilayer films based on biopolymers (pectin and chitosan) and their nanocomposites with silver nanoparticles have been prepared and evaluated. The buildup of multilayers was monitored using the quartz crystal microbalance with dissipation technique. The morphology of the obtained films was investigated by atomic force microscopy. We have demonstrated that pectin-Agcontaining films were characterized by the linear growth and smooth defect-free surface. When pectin-Ag was substituted for the pectin in the multilayer systems, the properties of the formed coatings were significantly changed: the film rigidity and surface roughness increased, as well as the film growth acquired the parabolic character. All prepared multilayer films have shown antibacterial activity against gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria.The significant decrease in the number of the adhered E. coli on the multilayer surface has been determined; moreover, many of the cells were misshapen with cytoplasm leaking. The prepared multilayer films showed a mild activity against S. aureus predominantly due to the antiadhesive effect. Our results indicate that antibacterial activity of biopolymer multilayers is determined by the film composition and physicochemical characteristics and can be associated with their antiadhesive and bactericidal behaviors.

Treatment of peritoneal adhesions are still of great importance today. One of the prophylactic measures is biodegradable gels and membranes. The objective of the investigation was to develop and to experimentally assess new materials based on pectin and alginate. Alginate hydrogel was prepared with 4.0, 7.0 and 10.0 weight per cent. The pectin sols were synthesized by the “green chemistry” method. To make flms and porous membranes the solution casting method and the freeze-drying technique were used accordingly. The materials were studied in vitro and in vivo. Their physical properties, biocompatibility, biodegradability, adhesion, the prevention effect, the possibility of using as a matrix for mesenchymal stem cell transplantation were assessed. Alginate hydrogel of 7.0 weight per cent didn’t cause postoperative complications and led to low adhesions incidence – in 10 % of cases (in the comparison group – 85.7 %). Pectin flms obtained by the solution casting method became deformed already in the physiological solution. Biodegradation of the flms was absent in the experiment, abscesses and infltrates in the abdominal cavity were noted. Mesenchymal stem cells didn’t attach to such flms. Porous pectin matrices synthetized by the freeze-drying technique became partially decomposed already in the physiological solution. In the experiment, these membranes were biodegraded in half animals with the formation of mild adhesions only in 25 %. Mesenchymal stem cells showed a good attachment to their surface. The developed materials based on alginate gel and porous pectin membranes showed a high biodegradation, good biocompatibility, adhesion the prevention effect and the possibility of using as a matrix for stem cells transplantation.