In this article, a series of silver-containing dressings are prepared by metal-vapor synthesis (MVS), and their antibacterial properties are investigated. The antibacterial activity of the dressings containing silver nanoparticles (AgNPs) against some Gram-positive, and Gram-negative microorganisms (Staphylococcus aureus, Staphylococcus haemolyticus, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Moraxella spp.) has been determined. Based on the plasmon resonance frequency of these nanoparticles, the frequency of laser irradiation of the dressing was chosen. The gauze bandage examined showed pronounced antibacterial properties, especially to Staphylococcus aureus strain. When 470 nm laser radiation, with a power of 5 mW, was applied for 5 min, 4 h after inoculating the Petri dish, and placing a bandage containing silver nanoparticles on it, the antibacterial effect of the latter significantly increased—both against Gram-positive and Gram-negative microorganisms. The structure and chemical composition of the silver-containing nanocomposite were studied by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and extended X-ray absorption fine structure (EXAFS). The synthesized AgNPs demonstrate narrow and monomodal particle size distribution with an average size of 1.75 nm. Atoms of metal in Ag/bandage system are mainly in Ag⁰ state, and the oxidized atoms are in the form of Ag-Ag-O groups.

Background. Metal nanoparticles can have unique properties that differ from those of the solid metal from which they are obtained. This is what determines the increased interest in them on the part of researchers from all over the world. Objective of the study: quantitative assessment of the antibacterial effect of silver and zinc oxide nanoparticles on polyantibiotic-resistant strains of gram-positive and gram-negative microorganisms. Material and methods. The synthesis of silver and zinc oxide nanoparticles was performed by laser ablation in a liquid. The physical properties and sizes of these nanoparticles were studied on the basis of spectral characteristics and atomic force microscopy. The study of the antibacterial resistance of the studied microorganisms was carried out, as well as a quantitative assessment of the antibacterial effect of the obtained nanoparticles based on the determination of the minimum inhibitory and minimum bactericidal concentrations. Results. All microorganisms used in the study were clinical pathogenic strains with polyantibacterial resistance. In this case, the minimum inhibitory concentrations of silver nanoparticles ranged from 7.81 to 31.25 μg/ml, and the minimum bactericidal concentrations - from 31.25 to 62.50 μg/ml, while for zinc oxide nanoparticles the values of the minimum inhibitory concentrations were within the range from 125 to 500 μg/ml, and the values of the minimum bactericidal - from 250 to 1000 μg/ml. Conclusions. The laser ablation method allows the synthesis of chemically pure nanoparticles of silver, zinc oxide, and, if necessary, other metals. Silver and zinc oxide nanoparticles are effective antimicrobial agents against polyantibiotic-resistant pathogenic microbial flora. The obtained values of the minimum bactericidal and minimum inhibitory concentrations must be taken into account in the subsequent clinical implementation of medical devices based on the use of metal nanoparticles.

The creation and implementation of new methods of study and local wound care occur in stages: in vitro, in vivo and clinical trials. The fundamental point of this process is to study the effect of the proposed agent on the experimental wound healing models of laboratory animals taking into consideration the common healing phases of course and similarity of animal wound healing with human one. At the initial stage the main problems faced by the researcher include the selection of the optimal experimental animal, while animal models are suitable for many skindisorders. The lack of strong evidence and relevant guidelines regarding the most appropriate form of local-wound care in literature and the fragmentation of the available information lead to the fact that during the development of the experiment, the scientists spend time, resources and operate on an additional number of animals. This article summarizes the literature data on the applied modeling methods as for the most common and rare types of skin wounds including burns and trophic ulcers in various laboratory animals. Those who prepared the experiment shouldhavepaidcloserattentionto thefeatures of creating such wounds and nuances so as the proven techniques of their creation in various species are shown. Variants of the course and prospects for the development of this area of surgery are presented.

Введение. Процесс выбора экспериментального животного для моделирования различных процессов организма человека, в том числе создания кожной раны, чрезвыйчайно сложен для исследователя ввиду разбросанности имеющихся данных по литературным источникам и отсутствия единого современного справочного пособия. Цель работы – анализ анатомо-физиологических и экономических особенностей разных видов животных при их выборе в качестве моделей для оценки ранозаживляющих свойств средств местного лечения кожных ран. Материал и методы. Выполнен анализ 35 русско- и англоязычных источников. Результаты. В представленной статье излагаются общие и отличительные особенности разных видов применяемых и перспективных экспериментальных животных. Продемонстрированы преимущества и недостатки выбора крупных или мелких животных, показаны ориентировочная стоимость и затраты на кормление. Выводы. При выборе экспериментального животного следует учитывать финансовые затраты, доступность, простоту содержания, опыт исследователя, анатомо-физиологическое сходство с человеком и информацию, которую мы хотим получить в результате эксперимента. В ходе моделирования кожной раны и интерпретации полученных данных надо принимать во внимание анатомо-физиологические особенности строения кожи животного.

Background. To carry out adequate antibacterial therapy directed against pathogenic microflora in patients with surgical infection it is necessary to take into account indicators of antibiotic resistance of leading etiological agents. The aim of the work is to study the spectrum and current dynamics of changes in antibiotic resistance of purulent pathogens in soft tissues of surgical patients. Material and methods. An analysis of the results of antibiotic resistance of the seeded leading microflora in patients with purulent processes of soft tissues was made. Results. Isolates of Staphylococcus aureus from surgical patients are characterized by high resistance to all β-lactam antibiotics, the combination drug trimethoprim-sulfamethoxazole, and macrolides. The resistance of Klebsiella pneumoniae and Proteus mirabilis to all studied β-lactam antibiotics, as well as fluoroquinolones, aminoglycosides, tetracyclines, nitrofurans, and chloramphenicol ranges from 37 to 100%. Escherichia coli resistance to β-lactams, fluoroquinolones, carbapenems, and aminoglycosides reaches 50-73%. A high level of antibacterial resistance is alsocharacteristic of other bacteria most often cultured in surgical patients. Conclusions. The most frequently cultured strains of both gram-positive and gram-negative groups of microorganisms from surgical patients are characterized by a high level of antibacterial resistance, reaching 100%. Currently, cases of polyantibiotic resistance and resistance even to reserve antibiotics are not uncommon. All this dictates the need to search for new classes of substances that have an antimicrobial effect, and metal nanoparticles may be one of them. Введение. Для проведения адекватной антибактериальной терапии, направленной против патогенной микрофлоры у пациентов с хирургической инфекцией, необходимо учитывать показатели антибиотикорезистентности ведущих этиологических агентов. Цель работы – изучение спектра и имеющейся динамики изменения антибиотикорезистентности возбудителей гнойных процессов мягких тканей у хирургических пациентов в настоящее время. Материал и методы. Произведен анализ результатов антибиотикорезистентности высеваемой ведущей микрофлоры у пациентов с гнойными процессами мягких тканей. Результаты. Выделяемые изоляты золотистого стафилококка от хирургических пациентов характеризуются высокой резистентностью ко всем β-лактамным антибиотикам, комбинированному препарату триметоприм-сульфаметоксазол, макролидам. Устойчивость Klebsiella pneumoniae и Proteus mirabilis как ко всем исследованным β-лактамным антибиотикам, так и фторхинолонам, аминогликозидам, тетрациклинам, нитрофуранам, левомицетину составляет от 37 до 100%. Резистентность Escherichia coli по отношению к β-лактамам, фторхинолонам, карбапенемам, аминогликозидам достигает 50-73%. Высокий уровень антибактериальной устойчивости характерен и для других бактерий, наиболее часто высеваемых у пациентов хирургического профиля. Выводы. Наиболее часто высеваемые от хирургических пациентов штаммы как грамположительной, так и грамотрицательной групп микроорганизмов характеризуются высоким уровнем антибактериальной резистентности, достигающей 100%. В настоящее время нередки случаи полиантибиотикоустойчивости, резистентности даже к антибиотикам резерва. Все это диктует необходимость поиска новых классов веществ, обладающих противомикробным действием, одними из которых могут быть наночастицы металлов.