Objective: To develop a detergent-enzymatic method and evaluate the quality of a decellularized pulp scaffold for regenerative endodontics.Materials and methods: Biomaterial and mesenchymal stem cells (MSCs) were derived from dental pulp that was obtained following third molar extraction indicated for orthodontic reasons in patients aged 14-18 years. The detergent-enzymatic method enabled to obtain a decellularized scaffold from pulp samples. The proliferative activity and viability of dental pulp-derived MSCs were assessed using trypan blue staining and XTT assay. To assess tissue response, Wistar rats underwent subcutaneous implantation of native and decellularized dental pulp. Explanted samples were stained with hematoxylin-eosin on days 7 and 14.Results: The detergent-enzymatic treatment of the dental pulp demonstrated the absence of nuclear material, whereas the histoarchitecture of the dental pulp was disturbed. The DNA content in the sample of the decellularized scaffold was 22.79 ± 2.1 ng/mg of tissue; the amount of DNA in the native sample was 78.5 ± 5.4 ng/mg of tissue. According to XTT assay results, no cytotoxicity of the decellularized scaffold against MSCs was found. Biopsy specimens of the rats with implanted decellularized dental pulp were characterized by no signs of inflammation.Conclusions: The study results will enable to create a biomaterial that can be the base of a tissue-engineered structure of the dental pulp and be used for the regeneration of the pulp-dentin complex.

Background. Lean production is mainly focused on increasing value in processes and improving the quality of services provided. These principles are implemented in medical organizations within the framework of the national project “Healthcare” and the federal project “Development of the Primary Healthcare System”. Introduction of lean technologies at all levels of the organization can serve as a highly effective method of positive changes. In 2023, Kuban State Medical University, together with the Ministry of Health of Krasnodar Krai and the Regional Center for Primary Healthcare, held a strategic session aimed at identifying problematic processes in medical organizations of the region and jointly searching for ways to solve them. The session involved 73 primary healthcare organizations. Its results formed the basis for a study of the project activity of medical organizations. Objective. To analyze the current state of project activities of medical organizations in Krasnodar Krai to achieve a “new model” through the introduction of lean technologies.Methods. A one-stage observational study was carried out in two steps. The first step involved participant observation. Its results determined a set of tools to be compiled. The second step of the study included a questionnaire survey and analysis of information. The data obtained from the questionnaire survey and observation were coded, the distribution and frequency were identified using frequency analysis and calculation of mean values. The qualitative analysis of open-ended questions was additionally applied.Results. The analysis showed that the prevailing number of projects are aimed at forming and developing the availability of medical care for the population (50.6 %), including projects focused on inclusiveness and provision of medical care to low-mobility patients at home. It was also revealed that 42 projects in four areas are planned for implementation in 47 organizations using lean technology tools in 2024. The study showed that 91.49 % of projects failed to calculate financial efficiency and evaluate project results in monetary terms. Meanwhile, 8.51 % of those who carried out the efficiency calculations lacked an analysis methodology and revealed the superficiality of the calculations. Of all the participants, 53.19 % reported the need for help in organizing and implementing project activities, and 36.17 % of the participants had enough resources to cope on their own. The three most problematic processes requiring joint work with colleagues included “Reducing the wait times for healthcare in regional medical organizations,” “Registration of discounted prescriptions” and “Preventive medical examination and dispensary.”Conclusion. The experience of a strategic session at Kuban State Medical University proved to be effective in improving the quality of implementation of lean technologies in medical organizations of Krasnodar Krai. The study was instrumental in assessing the current state of the project activities of medical organizations to achieve a “new model” through the introduction of lean technologies, as well as in identifying the most common areas of project activities and the main problems. The performed analysis revealed a positive trend in improving the quality of work of medical organizations in Krasnodar Krai and disseminating the lean technologies in primary healthcare.

Background: A pressing issue in modern purulent surgery is the growing number of microbial strains resistant to antibiotics. One of the strategies to address this issue is to develop novel wound dressings (WD) with incorporation of antiseptics that can prevent or reduce infection without conventional antibiotics.Objective: To compare the efficacy of chitosan-based WD with immobilized antiseptics and their combinations in in vitro and in vivo experiments.Materials and methods: We conducted a multistage randomized controlled in vitro and in vivo study investigating samples of chitosan-based WD with incorporated antiseptics (polyhexanide, octenidine dihydrochloride, povidone-iodine, and a combination of polyhexanide and octenidine) in international concentrations and diluted. The antimicrobial activity of antiseptics was evaluated in vitro by broth microdilution and disk diffusion methods. Staphylococcus aureus and Escherichia coli were used as reference cultures. For in vivo experiments, we formed experimental purulent wounds of soft tissues in laboratory animals (male rats weighing 300±50 g) according to our own method and treated the wounds with the investigated WD. The dynamics of the wound process was assessed by clinical and cytological data, as well as intravital ultrasonography findings.Results: Depending on the prolongation of time to maintain an effective concentration in the wound and minimal irritating effect on the tissue, we ranked antiseptic agents as follows: polyhexanide>octenidine>povidone-iodine. The combination of polyhexanide and octenidine did not demonstrate the expected synergistic effect; however, it had a positive therapeutic effect on the wound comparable to that of other antiseptics used alone. The comprehensive assessment of the wound process showed that WD with immobilized polyhexanide demonstrated the best wound healing and antiseptic effect. Reliable signs of wound healing with further positive dynamics were observed by day 7. It was almost 2 times faster compared with other experimental samples.Conclusions: Chitosan is a promising material to be used as a chemically inert matrix for programmed delivery of various drugs, including antimicrobial drugs, into the wound. The studied WD with immobilized antiseptics did not demonstrate a pronounced cytotoxic and depressing effect on processes of soft tissue remodeling and, on the contrary, significantly reduced the time of wound transition to the proliferation phase.

Background: Current studies show that hollow conduits in combination with various synthetic and biological fillers significantly accelerate functional recovery of peripheral nerves. One of such fillers can be a hydrogel based on the extracellular matrix of the dermis, which contains surface ligands capable of providing topographic and biological signals for nerve regeneration.Objective: To evaluate the effectiveness of rat sciatic nerve regeneration using a collagen conduit filled with dermal hydrogel in an in vivo experiment.Materials and methods: We evaluated the effectiveness of the NeuraGen® collagen conduit filled with dermal hydrogel and compared it with that of an autograft and the NeuraGen® hollow collagen conduit in experimental treatment of rat sciatic nerve defects larger than 1 cm. Male Wistar rats underwent sciatic nerve resection. We calculated the Sciatic Functional Index (SFI) and ratio of the calf circumference in an operated limb to that in an intact limb on days 30, 60, and 90 after implantation. We performed electrophysiological tests and explanted samples for hematoxylin-eosin staining on day 90 of the experiment.Results: When assessing the SFI and electrophysiological parameters, the group of animals with autografts and the group with the NeuraGen® collagen conduits filled with dermal hydrogel demonstrated similar results. We observed muscle atrophy, low SFI scores, and low velocity and short duration of the action potential in the group with the hollow NeuraGen® collagen conduits. Histological analysis of explanted samples of the collagen conduits filled with dermal hydrogel demonstrated areas of glial proliferation and the absence of pronounced degeneration of nerve fibers throughout the implant compared with autografts, indicating functional regeneration of nerve fibers.Conclusions: Evaluation of the effectiveness of rat sciatic nerve regeneration showed that the NeuraGen® collagen conduit filled with dermal hydrogel provides functional and morphological integration with the nerve compared with an autograft. Our findings can be used for further development and improvement of nerve conduits.

Background. Artificial neural network models can be used to analyze and predict structural components within the value dimension of the main processes in an outpatient clinic as indicators of patient satisfaction. Objective — to form and test the methodology for analyzing and predicting structural components within the value dimension of the main processes in an outpatient clinic, as indicators of patient satisfaction with availability and quality of medical care, using artificial intelligence. Methods. The results of questionnaires administered to 525 patients were used to analyze their satisfaction with GP appointments. A network ensemble consisting of radial basis network and multilayer perceptron was chosen as the basis for a neural network model. The model testing involved five outpatient clinics in Kirov. The total number of respondents comprised 217 patients. Statistical processing included data description and analysis. Qualitative attributes were represented by relative values ( P , %). The statistical significance of differences in qualitative data was assessed using the Chi-square test. The correlation between the observed and predicted data was assessed by means of nonparametric Spearman correlation analysis. The value of p <0.05 was chosen as the significance level ( p ). Statistical data processing was performed using Statistica 13.0. Results. Analysis of the value dimensions of satisfaction showed a predominance of “pre-appointment” stage: work of a registrar (85.29% significance in the receiving medical services), waiting time for an appointment with a doctor (66.76% respondents noted its significance), duration of waiting directly at the office (important for 69.11% of respondents). “Appointment” stage was formed according to the common procedure of a GP appointment (interview, examination, recommendations) and was assessed from the value perspective of the patient. The priority components included sufficiency of appointment duration (significant in 88.27% of cases), satisfaction with examination (significant in 85.14% of cases), as well as completeness and informativeness of consultation (significant in 89.9% of cases). A strong direct correlation between the observed and predicted data ( ρ xy = 0.9; p < 0.05) was found out. Statistically significant differences between the observed and predicted levels of general patient satisfaction were not revealed in all medical organizations. Conclusion. The suggested neural network models can be used as the basis when creating information management systems that monitor meeting the effectiveness criteria for a new model of a medical organization; as well as an essential support for administrative decisions related to organizing the optimal patient management.

Objective: To develop a biological implant that is an acellular dermal matrix (ADM), evaluate its use as a support material in tensionfree hernioplasty for ventral hernia, and compare it to that of the commercially available implant Permacol TM . Materials and methods: ADM was derived from the porcine dermis (Landrace breed) decellularized using detergents and enzymes. The quality of devitalization was assessed in vitro. We performed sublay hernioplasty in 4-month-old Landrace pigs using ADM (experimental group) and Permacol TM (control group). The specimens were explanted on day 120 of the experiment for histological and immunohistochemical examination. Results: All cellular elements were removed by the detergent-enzymatic treatment of the dermis; the native architecture of the dermis was slightly disrupted. The specimens of the commercially available chemically cross-linked biomaterial Permacol TM had better mechanical properties than ADM specimens; however, there were no significant differences in terms of cytotoxicity. The state of the tissues after the explantation (number of fibroblasts and endothelial cells) showed no differences in the result of using ADM and Permacol TM . In 120 days, the materials integrated into the tissues without the formation of adhesions or inflammation. Conclusions: Our findings show that ADM does not have cytotoxic properties, has adequate biomechanical parameters to effectively reinforce supporting soft tissues, does not cause an inflammatory response during implantation, and integrates fully into tissues. Our study demonstrates the effectiveness and utility of the developed ADM in surgical treatment of anterior abdominal wall defects.

Введение. Одним из наиболее перспективных способов терапии раневых поражений является использование коллагеновых гидрогелей. Добавление растительных БАВ кукурузы столбиков с рыльцами (КСР) может значительно повысить антиоксидантное, кровоостанавливающее и противовоспалительное действие коллагеновых гидрогелей. Цель работы – оценка цитотоксических и репаративных свойств поликомпонентного дермального гидрогеля (ДГ) с экстрактом КСР. Методика. Густой экстракт КСР получали вакуумфильтрационным экстрагированием кукурузы столбиков с рыльцами. Для получения ДГ образцы свиной дермы подвергали децеллюляризации 5% NaOH. Для оценки цитотоксичности использовали дермальные фибробласты DF-1 с последующим анализом жизнеспособности методом Live&Dead. Исследование эффективности использования ДГ с 2% экстрактом КСР проводили на самцах крыс Вистар: группа 1-я – крысы без лечения (контрольная группа), 2-я – крысы с лечением ДГ с экстрактом КСР (опытная группа), 3-я – крысы с лечением ДГ без экстракта КСР (группа сравнения). Крысам в области холки наносили скарифицированные раны 30х20х2 мм, после чего раны крыс группы 2-й и 3-й обрабатывали ДГ в течение 7 сут. Препараты образцов кожи крыс обрабатывали антителами к CD68, CD3 или окрашивали гематоксилином и эозином. Результаты. ДГ и экстракт КСР в разведении 1:50 не проявляли токсических эффектов, поэтому данное разведение экстракта КСР было выбрано для получения комбинированного ДГ с 2% экстрактом КСР. По результатам визуальной, гистологической и иммуногистохимической оценки эффективности репарации в контрольной группе и группе сравнения на 7-е сут эксперимента в области раны отмечалось образование струпа, а в опытной группе на те же сроки формирование всех слоёв кожи. В опытной группе на 2-е сут в препаратах определялось значительное количество CD3 и CD68-позитивных клеток, а на 7-е сут данных клеток обнаружено не было. Заключение. Используемая для получения комбинированного ДГ концентрация экстракта КСР не токсична для клеток. При оценке результатов лечения исследуемым комбинированным ДГ отмечается положительный репарационный эффект как относительно контрольной группы, так и группы сравнения. Introduction. One of the most promising methods for the treatment of wounds is application of collagen hydrogels. Supplements of plant bioactive compounds of corn silk (CS) can significantly enhance antioxidant, hemostatic, and anti-inflammatory effects of collagen hydrogels. The aim of the study was to evaluate the cytotoxic and reparative properties of a multicomponent dermal hydrogel (DH) with the CS extract. Methods. We obtained a thick CS extract by vacuum filtration. To obtain DH, samples of porcine dermis were decellularized with 5% NaOH. Cytotoxicity was assessed with DF-1 dermal fibroblasts, and their viability was determined by the Live&Dead method. The effect of DH with the 2% CS extract was evaluated on Wistar male rats: group 1, rats without treatment (control group); group 2, rats treated with DH with the CS extract (experimental group); and group 3, rats treated with DH without the CS extract (comparison group). Scarified wounds (30x20x2 mm) were inflicted in the shoulder area, then the wounds of groups 2 and 3 rats were treated for 7 days. Samples of rat skin were stained with hematoxylin and eosin or with CD68, CD3 antibodies. Results. The DH with the CS extract at a 1:50 dilution did not show toxic effects; thus, this dilution was chosen for the development of a composite DH with the 2% CS extract. According to the results of visual and histological assessment of the reparation effectiveness, a scab formed in the wound area in the control and comparison groups on day 7 of experiment, while in the experimental group, all skin layers formed during the same period. A considerable number of CD3, CD68-positive cells was detected in the preparations of the experimental group on day 2, while these cells were not found on day 7. Conclusion. The concentration of the CS extract used for the development of DH is not toxic to cells. Evaluation of the experimental treatment with the composite DH showed a positive reparative effect compared to the control or the comparison group.

Objective: To determine the optimal technological modes for the preparation of platelet-rich plasma (PRP) using standard laboratory equipment.Material and methods: Blood for the research was taken from 25 healthy volunteers. Its centrifugation was performed on a standard CM-6M laboratory centrifuge using various modes and two types of vacuum tubes with lithium heparin containing separation gel and without it. The number of platelets and leukocytes was calculated in the upper, lower and middle layers of the obtained plasma sample.Results: Plasma samples obtained during centrifugation modes from 415 to 1660 g for 10 minutes using test tubes that do not contain separation gel are optimal in terms of the number of platelets. Plasma intake from the lower layer of the obtained sample after centrifugation is always accompanied by the inclusion of leukocytes in its composition, which can lead to undesirable tissue reactions when it is used.Conclusion: To obtain PRP, it is possible to use standard laboratory equipment in the centrifugation mode from 415 to 1660 g for 10 minutes using test tubes that do not contain separation gel. Plasma sampling for clinical use should be carried out from the middle layer of the obtained sample.

Разработка лекарственных препаратов для лечения ран представляет собой актуальную теоретическую и прикладную задачу, в связи с чем обоснованна целесообразность разработки состава и технологии поликомпонентного репаративного действия на основе биополимеров дермы и комплекса биологически активных веществ кукурузы столбиков с рыльцами. Проведенные исследования позволили предложить оптимальный состав и технологию получения поликомпонентного геля. Целью настоящего исследования являлось определение критериев и методик контроля показателей качества поликомпонентного геля репаративного действия. В качестве критериев качества поликомпонентного геля изучены показатели «описание», рН, «микробиологическая чистота», «подлинность» и «количественное содержание суммы флавоноидов в пересчете на лютеолин-7-гликозид». The development of drugs for the treatment of wounds is an urgent theoretical and applied problem, in connection with which the expediency of developing the composition and technology of a multicomponent reparative action based on dermal biopolymers and a complex of biologically active substances of corn silk is substantiated. The studies carried out made it possible to propose the optimal composition and technology for obtaining a polycomponent gel. The purpose of this study was to determine the criteria and methods for monitoring the quality indicators of a multicomponent reparative gel. As criteria for the quality of a multicomponent gel, the indicators "description", pH, "microbiological purity", "authenticity" and "quantitative content of the sum of flavonoids in terms of luteolin-7-glycoside" were studied.

Background. The healing of skin wounds having various etiologies is known to involve a multistep process characterized by certain intercellular interactions affecting dermal cells, their attachment, migration, and differentiation. Here, recovery is interpreted as the return of dermis to its original state. The fact is, however, that the dermal extracellular matrix (ECM) is structurally impaired, which suppresses the regulatory and repository functions of the dermis, leading to the formation of a scar that inhibits several biological functions in the affected area and causes aesthetic problems associated with mobility.Objectives. To evaluate the structural features of dermis during wound healing using a calcium-containing biodegradable implant.Methods. The study used 60 rats that were inflicted with a third-degree burn injury (partially damaged dermis). The selected animals were divided into two groups: experimental and control. On post-burn day 14, a calcium-containing biodegradable implant was administered to rats from the experimental group, while a sterile saline solution was used in the control group. Material was sampled at two months (74 days) and four months (134 days). In order to assess the morphological state of the burn area, its sections were stained with hematoxylin and eosin, according to Mallory and Van-Gieson. For the selective detection of collagens, immunohistochemical tests using antibodies to collagen types I and III (Abcam, England) were employed. To characterize dermal cells, the authors used antibodies to vimentin (LabVision, USA), as well as to СD-68 (cluster of differentiation 68), α-SMA (alpha-smooth muscle actin), CD-105 (cluster of differentiation 105), and VEGF (vascular endothelial growth factor) receptors (Abcam, England). The obtained results were processed using the Statistica 6 software (StatSoft, USA).Results. The administration of a calcium-containing biodegradable filler during the burn healing process was found to ensure local fibroblast activation with the formation of collagen types I and III. When the implant residence time was prolonged up to four months, an increase in the number of macrophages expressing CD-68 receptors was observed. Of note is that these cells retained their localization, while α-SMA-expressing cells were localized in both the superficial and deep dermal compartments. The number of cells expressing CD-105 and VEGF rose as well.Conclusion. The use of the biodegradable filler is found to be promising in terms of post-burn dermal regeneration, as well as providing a dermal ECM, whose collagen network composition and assembly are similar to the original. Here, macrophages act as the primary synthesis regulators of the dermal ECM and stimulate fibroblasts, which ensures re-epithelialization and angiogenesis of the inflicted area.

Background. With the introduction of synthetic mesh implants into clinical practice, the recurrence rate of postoperative ventral hernias was signifi cantly reduced. The extensive use of synthetic implants led to the development of specifi c complications. The development of biological implants, based on extensively purifi ed decellularized collagen matrix of xenogeneic origin is highly relevant due to the fact that, unlike synthetic analogues, they have a biological origin and biodegrade in a natural way, gradually being replaced with newly formed connective tissue. The use of bioprostheses reduces the risk of complications.Objectives. To conduct a comparative evaluation of the biomechanical characteristics of acellular dermal matrix, obtained by detergent-enzymatic decellularization, and commercially distributed Permacol™ matrix.Methods. Acellular dermal matrix (ADM) was created by using samples of native skin of pig of Landras breed aged 4 months. The dermis was processed by means of detergent-enzymatic method. In order to evaluate and compare the mechanical properties of acellular dermal matrix, the biological samples were divided into 2 groups of 15 samples each. The fi rst group included acellular dermal matrix samples, the second group — native samples of pigs unprocessed dermis. The control group consisted of samples of PermacolTM Surgical Implant, xenotransplant for hernioplasty approved for use in the Russian Federation (Covidien, France). All samples were tested wet using universal testing instrument Instron 1122. MedCalc Statistical Software (Belgium) was used for statistical processing of the study results.Results. In the present study, pig dermis was processed using a detergent-enzymatic method to produce ADM. Routine histological examination confi rmed the removal of all cellular elements, and at the same time it was proven that the native structure of the dermis remained intact during its processing. The mechanical characteristics of xenogenic ADM were further determined. Its tensile strength was 9.1 ± 0.6 MPa (910 N/cm2 ), elongation to break was 21.1 ± 2.3%, and elastic modulus was 50.0 ± 1.6 MPa. These characteristics largely corresponded to the strength characteristics of native pig dermis and far exceeded the necessary physiological parameters. PermacolTM control was tested in two directions (longitudinal and transverse). In the longitudinal direction, the sample had higher mechanical characteristics: strength — 12.0 ± 1.7 MPa, elongation to break — 29.7 ± 2.4%, stiffness modulus — 47.2 ± 6.5 MPa. In the transverse direction, all indicators were 1.5–2 times lower.Conclusion. The developed xenogeneic biological implant in the form of ADM demonstrates rather good characteristics of plasticity, tensile strength and elasticity, to be used as a biological endoprosthesis for plasty of hernia defects of the abdominal wall of any size and shape.

Background . Wounds of various aetiology are among the most frequent traumatic injuries. A prospective route to improve treatment of this nosology is the development of novel or advancement of the already on-stage dressing materials. Objectives. A comparative experimental assay of novel chitosan-based wound dressings in the healing of soft tissue wounds of different genesis using ultrasound to control biodegradation of the developed dosage form. Methods. Soft tissue wounds were modelled in experimental animals, conventional and lineage male rats, 275 (± 25) g body weight, and male rabbits, 2,900 (± 150) g weight, using a proprietary methodology (Patent on invention RU No. 2703709 dated 23 August, 2018). Two wound dressing samples selected as most promising and applicable in large-volume soft tissue aseptic wounds were tested in the final step of experiment. Ultrasound imaging of the model wound area during the sample material biodegradation was used to control the wound process in more detail. At all steps of experiment, animal models were handled in compliance with GOST 33044-2014 “Principles of Good Laboratory Practice”. Histomorphological assays were carried out with common protocols. Variation statistics was used for the data analysis, including the mean (M) and standard mean error (± m) estimation. The level of statistical significance was p < 0.05. Results. The animal assays and comprehensive evaluation of the obtained data revealed a high healing efficacy of chitosan-based wound coatings. The analyses of wound dressing samples have confirmed their predesigned properties: scaffold stability, capillarity, biodegradability and matrix capacities for the carried drug delivery. Additionally, ultrasound was proved effective to estimate dynamics of the coated wound healing and biopolymer biodegradation processes. Conclusion. The developed chitosan-based wound dressings exhibited efficacy in an experimental model of the soft tissues wound process. The use of ultrasound to study dynamics of the wound process and coating biodegradation provided an adequate congruence between the imaging and tissue histomorphology data, as well as the structure and properties of coating material.

Despite advancements in modern surgery in the treatment of cutaneous injuries, the search for new methods of ensuring faster and more effective wound healing appears especially urgent today. Tissue engineering is undoubtedly of interest when it comes to developing such technologies. Objective: to determine the optimal protocol for obtaining a decellularized dermal matrix scaffold for subsequent development of tissue-engineered skin. Materials and methods. One Landrace piglet was used as the experimental animal. After preliminary skin treatment with dermatome, 0.3 cm thick samples were taken. Two decellularization protocols were considered: protocol No. 1 was based on the use of Triton X-100 and deoxycholate, protocol No. 2 was only based on deoxycholate. There were 5 processing cycles in total for the 2 protocols. After treatment, acellular matrix scaffolds were examined through histological analysis and quantitative determination of DNA concentration. Next, static recellarization of the matrix scaffolds was carried out with porcine dermal fibroblasts. After that, the matrix scaffolds were tested for cytotoxicity using XTT test and differential staining test to differentiate between live and dead cells. Results. Comparative analysis of the two protocols for porcine dermis decellularization showed that both protocols effectively remove cells and nuclear material, while maintaining the architectonics of the intercellular substance intact, since fibrous structures are not destroyed. But when assessing the biocompatibility of matrix scaffolds based on analysis of cell viability according to data obtained from XTT test and cell–matrix adhesion, the matrix scaffold processed under protocol No. 1, shows advantages. Conclusion. In this study, a decellularization protocol based on Triton X-100 and deoxycholate was noted. The results obtained mark the first stage towards developing a tissue-engineered skin.