Antioxidant Activity of Silver-containing Bionanocompositions Based on Humic Substances in Cell Culture

Introduction. Silver nanoparticles are promising agents for suppressing resistant strains of microorganisms and accelerating the purulent wounds healing. Oxidative stress disrupts normal wound healing processes, which leads to the formation of chronic non-healing wounds. Therefore, the determination of the ability of new wound healing agents to decrease the production of reactive oxygen species is a relevant task.Aim. The aim of the current study was to investigate the effect of silver-containing bionanocompositions based on humic substances on the basal and tert-butyl hydroperoxide-stimulated production of reactive oxygen species at the normal fibroblasts 3T3-L1 cell culture in vitro.Materials and methods. The study was carried out on 7 samples of initial humic substances and biomaterials with silver nanoparticles synthesized in the Laboratory of Natural Humic Systems, Faculty of Chemistry, Moscow State University named after M. V. Lomonosov. The intracellular production of reactive oxygen species was assessed using a 2,7-dichlorodihydrofluorescein diacetate fluorescent probe. Cells were cultured with samples for 24 h; tret-butyl hydroperoxide was used to stimulate the production of reactive oxygen species. Detection was performed fluorometrically using a microplate reader.Results and discussion. The most pronounced antioxidant activity was demonstrated by three samples of biomaterials with silver nanoparticles ultradispersed in humic substances matrices (CHS-AgNPs, CHP-AgNPs and CHE-AgNPs), which allows us to consider them as the most promising pharmaceutical agents for the treatment of purulent-inflammatory processes. The most probable mechanism of the high antioxidant activity of the studied biomaterials in relation to intracellular reactive oxygen species is the intrinsic activity of humic substances to bind reactive oxygen species, while silver nanoparticles in biomaterials catalyze the reduction processes of their interaction with reactive oxygen species.Conclusion. For the studied samples of biomaterials with silver nanoparticles ultradispersed in matrices of humic substances pronounced antioxidant activity was shown. Together with antibacterial properties, it makes it possible to consider them as potential agents for purulent wounds healing accelerating.

Treating diabetic foot syndrome at the General Surgery Clinic of the S.M. Kirov Military Medical Academy

We examined 180 patients with purulent-necrotic complications of diabetic foot syndrome, in whom the proposed diagnostic algorithm was used. Magnetic resonance imaging of the feet, ultrasound Doppler with duplex angioscanning, magnetic resonance and computed angiography of the lower extremities, as well as assessment of transcutaneous oxygen tension were performed. Surgical treatment tactics depended on the form of the diabetic foot syndrome, as well as the severity of the disease. As a local treatment, physical methods were used to accelerate the course of the wound process. The proposed diagnostic algorithm for the diagnosis and selection of surgical treatment for various forms of diabetic foot syndrome has made it possible to reduce the number of “high” amputations and maintain a supporting limb. Purpose of the study is to improve treatment outcomes for purulent-necrotic complications of diabetic foot syndrome by developing and applying a diagnostic algorithm and differentiated treatment tactics. The main group consisted of 180 patients with purulent-necrotic complications of diabetic foot syndrome, in whom the developed diagnostic algorithm and differentiated tactics of surgical treatment were used, as well as physical methods of influencing the wound process (ultrasonic cavitation and local ozonation) were used as local treatment. The control group included 40 patients with purulent-necrotic complications of diabetic foot syndrome, whose treatment involved the use of drugs that improve the rheological properties of blood and tissue microcirculation (rheopolyglucin, trental, actovegin) according to conventional schemes. Local treatment included sanitation and treatment of wound and ulcerative surfaces with antiseptic solutions and ointments, depending on the phase of the wound process. Data analysis in this group was carried out based on a retrospective study of case histories and an assessment of long-term results of treatment by follow-up examinations and telephone interviews. Control group included 25 (63%) men and 15 (37%) women; the average age was 67.3±10.3 years. The developed unified approaches in diagnosing and treating patients with purulent-necrotic complications of diabetic foot syndrome, who, in complex treatment, underwent staged necrectomy with simultaneous ultrasonic cavitation of purulent wounds and their ozonization, can reliably reduce the number of ulcer recurrences from 28% to 2.7%, high amputations by 34%, and the number of re-amputations ― 10 times. The use of minimally invasive surgical technologies for the rehabilitation of deep purulent foci of the foot, in comparison with the classical principles of treatment of purulent wounds, makes it possible to achieve a complete cleansing of wounds, preparation for plastic surgery, and an increase in the number of functional supportable lower limbs by 42.7%. According to the data obtained, it is optimal to perform sanitizing operations after revascularization of at least one artery no earlier than 3–4 days, which makes it possible to increase their efficiency and reduce the number of repeated surgical interventions. The approach to managing patients with diabetic foot syndrome at all stages of treatment and rehabilitation should be interdisciplinary and include the following specialists: endocrinologist, orthopedist, surgeon, psychologist, trained nursing staff.

Physico-Chemical Properties of Antiseptics in Surgery: What is not Taken into Account in Treating Long-Term Non-Healing Wounds

The treatment of long-term non-healing wounds in the conditions of purulent surgery departments, widely uses solutions of chemotherapeutic and antiseptic agents. The most common are the solutions of 3–6 % hydrogen peroxide and solutions of 2–10 % sodium chloride. As a rule, solutions of these drugs are used to treat non-healing, particularly, purulent wounds, bedsores and trophic ulcers. Therefore, solutions are injected into the wound area repeatedly in the form of course therapy. The findings show that the mechanism of action of these drugs and the effect of treating long-term non-healing wounds is largely determined by such physical and chemical factors of their local interaction as concentration of the main ingredients, osmotic, alkaline activity and local temperature. The findings point out the leading role of the local temperature and the dependence of the local effect on the concentration. They describe the essence of the innovative method of treatment.

Morphological signs of the effectiveness of application sorbent in the treatment of purulent wounds (experimental study)

Objective. To prove experimentally the effectiveness of a new generation of application sorbent by studying the morphological changes during the wound process. Methods. Depending on the drug used to treat purulent wounds, we divided the animals into three groups. In the main group (group I) the study was performed on 20 rats, they used an application sorbent, which includes aerosil with immobilization on its matrix ornidazole (Patent of Ukraine for utility model № 115228). The comparison group (group II) consisted of 10 rats, which used the known sorbent "Gentaxan", which includes: gentamicin sulfate, L-tryptophan and zinc sulfate. The comparison group (group III) was 10 rats. In this group for the treatment of purulent wounds used 10% sodium chloride solution, followed by a transition to ointment "Levomekol", which includes chloramphenicol and methyluracil. Results. The results of the study show that in the main group already on the seventh day in comparison with the comparison groups was found granulation tissue with a large number of newly formed vessels of the microcirculatory tract and pronounced proliferation of fibroblasts, indicating acceleration of wound healing. In the comparison groups, the regeneration process was slower. Conclusion. Pathomorphological examination revealed that drugs with sorption properties contribute to a faster reduction of edema and inflammation, and treatment with application sorbent used in the main group, significantly accelerates the processes of connective tissue repair and wound epithelization, ie accelerates wound healing processes with comparison groups.

TREATMENT OF LONG-TERM NON-HEALING PURULENT WOUNDS OF THE LOWER LIMBS USING VAC-THERAPY

Summary. The purpose of the study is - To improve the results of treatment of patients with purulent long-term non-healing wounds of the lower extremities using the method of local negative pressure.in purulent long-term non-healing wounds (PLTNHW). Objectives of the research — according to the clinic’s data, to study the features of the course of the wound process and the microbiological characteristics of purulent long-term non-healing wounds of the lower extremities when exposed to the wound surface of local negative pressure. Conclusions. The use of the local negative pressure method in the complex treatment of patients with purulent long-term non-healing wounds of the lower extremities helps to reduce the duration of the phases of the course of the wound process, early tissue decontamination and a rapid reduction in the size of wound defects.

PRECLINICAL TRIALS FOR ADVANCED CHITOSAN-BASED COATINGS IN TREATING PURULENT WOUNDS

Wound healing is a complex set of body responses to damaged tissues, which manifests itself through local destructive-inflammatory changes and general reactions. There are numerous coatings used currently in clinical practice to treat wounds. These coatings serve to develop a wet anti-bacterial environment, which is essential to facilitate the healing process. This work focuses on studying multifunctional coatings, which are based on chitosan, a biocompatible polymer featuring wound-healing properties. The distinctive feature to be found in chitosan fibers is their density and the orientation of pores. The coatings within this study were tested on scalped full-layer skin wounds of male Wistar-Kyoto rats and male rabbits. The sample with a dense structure and low biological resorption was found to be effective in performing the function of a framework, as well as in ensuring proper drainage at the affected area. This is important when treating purulent wounds. The experimental sample with a high degree of adhesion and a shorter biodegradation life can be recommended for treating wounds with no purulent-inflammatory issues, for granulating wounds, as well as a drug carrier-matrix. The studied wound coatings have revealed their medical efficiency at the preclinical stage (in vivo). Using wound coatings with specified structural and functional features would allow making a reasonable choice when selecting a coating depending on the stage of wound healing course.

Rational antimicrobial therapy and wound healing stimulation in patients with surgical infection

The objective of the study was to develop the problem of complex treatment of surgical infections of the skin and soft tissues (SISST).The studies were carried out in 201 patients with SISST who were treated at the Department of Purulent Surgery of the Hospital Surgery Clinic of the EE “Vitebsk State Medical University” in 2017–2020. As a result, it was developed: a protocol for a rational use of antibiotics in the patients with SISST, an effective regimen for use of antiseptic drugs, a method for treating purulent wounds with autologous bone marrow aspirates.For 13 years, there have been significant changes in the etiological structure of gram-negative problematic pathogens in patients with purulent wounds. The share of K.pneumoniae increased approximately 8 times (by 12.25 %; p < 0.05), and A.baumannii ‒ 9 times (by 14.69 %; p < 0.05). The share of MRSA remained virtually unchanged. The resistance of problem microorganisms to almost all antibacterial drugs significantly increased. For MRSA-induced SISST, glycopeptides (vancomycin) should be recommended as a drug of choice, and oxazolidinones (linezolid) and glycylcyclines (tigecycline) should be recommended as a reserve; K. pneumoniae ‒ colistat and tigecycline; P. aeruginosа ‒ carbapenems (doripenem) and colistat; A. baumannii ‒ penicillins or cephalosporins with sulbactam (ampicillin + sulbactam) and colistat.It was found that septomyrin and 0.02 % chlorhexidine bigluconate have the greatest activity against the leading representatives of the microflora of purulent wounds. With a combined use of septomirin and chlorhexidine, the bacterial contamination of wounds decreased below the critical level already on the 2nd day after surgical treatment (p < 0.01).To stimulate wound healing, sternocentesis is performed and automyeloaspirate is taken. The curettage of the wound and the aspirate introduction into the wound edges and the application to the wound surface are performed. It has been established that, along with the pelvic bones, the sternum can be an alternative source of red bone marrow. The myeloaspirate volume obtained by sternal puncture varied from 10 to 140 ml. The developed method allows us to reliably reduce the duration of the 2 phase of the wound process by 7 days (р < 0.01).

Influence of the combined use of septomyrin and chlorhexidineon bacterial load of purulent wounds

Objective: to study the MIC90 of the most commonly used antiseptics for the main representatives of the microflora of purulent wounds and to study the influence of the most effective in vitro antiseptics on the bacterialload of the wound surface in patients with purulent wounds.Material and methods. Bacteriological studies determining the MIC90values of antiseptic drugs were performed on 70 clinical isolates. Clinical studies determining the level of the bacterial load of the wound surface were performed in 30 patients with purulent wounds.Results. Septomyrin and 0.02 % chlorhexidine bigluconate have been found to be the most active drugs against the main representatives of the microflora of purulent wounds in our region. In the combined use of septomyrin and chlorhexidine, the bacterial load of the wounds decreased below the critical level already 2 days after surgical debridement (p < 0.01), while in the single application of septomyrin, this had occurred only by the fifth day (p < 0.01), and chlorhexidine — by the sixth day (p<0.01).Conclusion. The combined use of septomyrin and 0.02 % chlorhexidine bigluconate is characterized by high clinical effectiveness in the local treatment of purulent wounds during the first phase of the wound healing process.

Optimization of provision of specialized medical care for patients with maxillofacial neoplasms in the Penza region of Russia

Recent years are characterized by the active development and advancement in clinical practice of the method of photodynamic therapy (PDT). PDT shows high effectiveness in the treatment of skin tumors, digestive, nervous, respiratory systems, in gynecology, ophthalmology. Antimicrobial PDT is successfully used in the treatment of purulent wounds and infectious diseases. One of the most actively developing applications of antitumor PDT is the treatment of maxillofacial tumors.The study assessed the organization of medical care for patients with malignancies of the maxillofacial region (MNMR) in the Penza region and the provision of oncologists, maxillofacial surgeons specializing in the treatment of tumor pathology. In the course of the study, the incidence of MNMR of the population of the Penza region and the gender and age structure were determined. The shortcomings of the organization of medical care for patients with MNMR are indicated.