Coronavirus infection (COVID-19), caused by severe acute respiratory syndrome 2 (SARS-CoV-2) RNA virus, has become a global problem in the world. Its consequences are of great importance for the health status of both adults and children, since the number of lethal outcomes and life-threatening complications has reached high rates. Of particular importance is coronavirus damage of important organs in childhood, due to the possible impairment of their functions and the development of later distant complications. Thus, the formation of acute kidney injury (AKI) in children is an independent risk factor for hospital mortality and disability. An important role in the development of this pathological condition is given to the development of endothelial dysfunction due to the activation of a number of pro-inflammatory cytokines and other biomarkers of endothelial disorders. Endothelitis, endothelial injury, endothelial cell dysfunction, and impaired microcirculatory function in various vascular beds all contribute markedly to life-threatening complications of COVID-19 such as venous thromboembolism and multiple organ failure. Endothelial dysfunction is the main determinant of microvascular disorders due to a shift in vascular balance towards greater vasoconstriction and subsequent organ ischemia, inflammation with concomitant tissue edema and procoagulant condition. In general, understanding the mechanisms of endothelial activation and dysfunction during COVID-19 infection can contribute to early detection of individuals, especially children, at risk of severe complications. Further study of endothelial dysfunction in the pathogenesis of AKI in children with COVID-19 is promising to determine a personalized approach to the management of pediatric patients with COVID-19.

Osteoarthritis is a chronic disease that causes the development of permanent disability of the patient and is a significant social and economic burden on the health care system of developed countries. It should be noted that the current variability of approaches to the treatment of osteoarthritis is due to a number of factors, including differences in etiology, severity of course, and clinical symptomatology of the disease, which must be analyzed and taken into account when choosing therapy. The modern approach to therapy of osteoarthritis includes the use of symptomatic slow-acting drugs (SYSADOA). Objective: to review the literature data on the role of SYSADOA in the therapeutic arsenal of patients with osteoarthritis. Materials and methods. Literature review and analysis was conducted by keyword using electronic resources of PubMed, MedLine databases in the period from 2010 to 2023. Results. The analysis of the studies conducted to date on the establishment, validity and feasibility of the group of symptomatic slow-acting drugs in the therapy of OA to control the progression of the disease showed the presence of very controversial and debatable provisions, which is associated with a diverse range of available glucosamine and chondroitin sulfate drugs. The greatest evidence base and efficacy are found in prescription preparations of crystalline glucosamine sulfate and chondroitin sulfate. Conclusion. The use of SYSADOA requires further study, including randomized placebo-controlled trials using modern joint imaging techniques.

Objective: to study the features of the course of viral pneumonia in patients with diabetes mellitus. Materials and methods. A random sampling method was used to conduct a retrospective analysis of 300 archival medical records of inpatients with laboratory-instrumentally confirmed COVID-associated pneumonia for the period 2020-2022. Results. As a result of the study, two groups were formed - the main and control. The main group included 150 patients diagnosed with diabetes mellitus; the control group consisted of 150 patients without diabetes mellitus. The average number of bed-days spent by the main group in the hospital was 12.4 days, the control group - 10.5 days (р˂0.001). Significantly more often, the main group of patients is diagnosed with a serious condition at the time of hospitalization, as well as unilateral localization of the pathological process in the lungs. Conclusion. In patients with diabetes mellitus and pneumonia caused by a new coronavirus infection, a dependence of the volume fraction of lung tissue damage on the level of hyperglycemia was revealed. In patients with DM, anticoagulant therapy was carried out longer during inpatient treatment, combinations of several groups of antibacterial drugs were used more often, and the starting dose of glucocorticosteroids was also higher.

Objective: to conduct a comparative analysis of the level of α-defensins (HNP1-3) and cytokines (IL-8, IL-4, IL-17, TNFα) to identify predictors of chronic acute urticaria. Materials and methods. There were 57 patients under observation with acute recurrent urticaria, divided by the level of serum IgE into 3 groups: group 1 - patients with IgE levels up to 100 IU / ml, group 2 - with IgE from 100 to 500 IU / ml, group 3- with IgE over 500 IU / ml. The quantitative content of α-defensins (HNP 1-3) in blood plasma and cytokines (IL-8, IL-4, IL-17A, TNF-α), IgE in blood serum was determined by solid-phase ELISA. Rusults. The study showed that in all patients with acute urticaria there was an increase in the level of serum cytokines (IL-8, IL-17A, TNF-α) and α-defensins HNP 1-3, the most pronounced in patients of group 3 with an IgE level of more than 500 IU/ml According to the results of correlation analysis, the strongest direct correlation was found between the level of α-defensins HNP 1-3 and IL-17A. In patients of groups 2 and 3, a strong direct correlation was also found between the level of HNP 1-3 and TNFα. Conclusion. The results of the study showed that a significant increase in the level of cytokines IL-4, IL-8, IL-17A, TNF-α and α-defensins (HNP1-3) in patients with acute recurrent urticaria indicates their key role in the pathogenesis of the disease. The revealed direct correlation between the levels of α-defensins, IL-17A and TNF-α reflects the dynamics of the course of immunoinflammatory process and can be regarded as predictors of chronic acute urticaria.

Objective: to study the effects of the GHK peptide and its structure analogues on the mechanisms of innate immunity and lipid peroxidation in wound. Materials and methods. The experiments were performed on 70 male Wistar rats. The skin wound was modeled by applying a full-layer wound with an area of 250 mm2 on the animal's back. The peptides Gly-His-Lys (GHK), D-Ala-Gly-His-Lys (D-Ala-GHK), and Gly-His-Lys-D-Ala (GHK-D-Ala) were used in doses of 0.5 μg/kg and 1.5 μg/kg, which it was administered intradermally in doses of 0.5 μg/kg and 1.5 μg/kg in a volume of 0.1 ml for 3, 7 or 10 days. The activity of lipid peroxidation (LPO) processes in blood serum was assessed by the content of malonic dialdehyde (MDA) and acylhydroperoxides (AHP). The antioxidant mechanisms were evaluated by determining the activity of catalase and the total antioxidant activity (OAA) of blood serum. Phagocytic activity of blood neutrophils was assessed by phagocytic index (PI) and phagocytic number (PN). The activity of oxygen-dependent mechanisms in phagocytes was evaluated in a spontaneous nitroblue tetrazolium test (NBT). Results. After the administration of GHK, the tendency to PI, PN and completeness of phagocytosis prevailed, which mainly persisted with the use of peptides D-Ala-GHK and GHK-D-Ala. At the same time, the GHK-D-Ala peptide at a dose of 1.5 μg/kg had the most stable effect on phagocytic activity. The data obtained in the NBT are largely consistent with the PN indicators. At the same time, the effects of structural analogues, unlike GHK, were manifested throughout the experiment. Significantly significant changes in the activity of LPO and antioxidant mechanisms were observed with the use of all peptides. However, their dynamics, orientation and severity throughout the experiment were quite complex. Conclusion. GHK and its structural analogues, D-Ala-GHK and GHK-D-Ala, had an effect on the indicators of innate immunity and LPO in a skin wound, the severity and direction of which depends on the healing period. At the same time, the most pronounced and stable effects were observed when using GHK-D-Ala. That demonstrates the importance of protecting the tripeptide molecule from the action of carboxypeptidases.

There is now a growing evidence of the long-term effects of COVID-19, affecting almost all human systems and organs, including the kidneys. The objective of this paper was to study pathogenetic and structural and functional changes in the kidneys in patients with COVID-19 infection. Materials and methods. Articles were searched in PubMed, Medline, Google Scholar, E-library, Clinical Trial databases using the keywords "post-COVID syndrome," "renal damage (kidney disease)," "COVID-19," "SARS-CoV-2," and "glomerulonephritis" in Russian and English. Databases reporting cases of detectable renal damage following a prior coronavirus infection published by September 28, 2022 were used. This review includes literature reviews, clinical cases, and original studies reporting the confirmed cases of detectable renal damage after confirmed prior COVID-19. The sources that focus only on renal damage during the acute period of coronavirus infection have been excluded. Results. Primary viral damage is carried out through the effect on the receptors of angiotensin-converting enzyme-2 (ACE-2). No less important mechanisms of viral damage are immunological and inflammatory reactions, dysfunctions of the complement system, leading to multiple organ failure. The long-term consequences of coronavirus infection on the kidneys were manifested in a decrease in the estimated glomerular filtration rate (eGFR), an increase in creatinine levels, proteinuria, and microhematuria. Dickkopf-3 protein (uDKK-3) may become a promising marker of kidney damage. Post-COVID renal disease can occur both de novo and with a previous renal complication of COVID-19. The most common morphological variants of kidney damage were tubular lesions and various morphological variants of glomerulonephritis. Conclusion. The association of COVID-19 and kidney damage in the post-COVID period is supported by common mechanisms of pathogenesis, including direct viral damage through ACE-2, inflammatory and immune reactions of the body. These data are confirmed by detectable markers of inflammation and damage to the renal tissue, the morphological picture of necrosis, fibrosis of the renal parenchyma in patients with COVID-19 infection.

Studies (domestic and foreign) on the effect of vitamin D on muscle strength, muscle recovery rate, maximum oxygen consumption and prevention of skeletal muscle injury reduction have been analyzed. At the same time it was found that athletes are susceptible to hypovitaminosis no less often than standard population groups due to higher physical loads. It is unequivocally possible to say that vitamin D supplementation improves the physical fitness of athletes and can correct their condition in the autumn-spring period. Objective: an analysis of literature data based on the significance of the pharmacological effects of vitamin D in the functioning of the musculoskeletal system of the body and its role of improving athletic performance. Material and methods. The Pubmed/MEDLINE digital scientific library was chosen as the main source of information. Additionally, the search included the repositories of open access preprints from eLIBRARY.RU for 2016-2022. Key words for the search query were "vitamin D," "calcitriol," "sports," and "athletes." The results of the study are reported taking into account PRISMA recommendations. Results. Duration and quality of insolation directly affect vitamin D levels. Additional sun exposure combined with the use of vitamin D preparations contributes to the elimination of vitamin D deficiency. Vitamin D deficiency can lead to decreased intranuclear VDR concentrations and decreased VDR gene expression, which contributes to myopathy following atrophy of type IIA muscle fibers. Additional enrichment of special electrolyte solutions with water-soluble vitamin D is reasonable. Conclusion. Continuous monitoring of the concentration of 25(OH)D in the blood serum of athletes is an integral part in the development of recommendations for improving health and sports performance in training and competitive regimes. Individual correction of vitamin D should be carried out in accordance with changes in its level in each athlete.

Low-quality herbal raw materials and the products obtained from them are important sources of various ecotoxicants, especially heavy metals, entering the human body. Aqueous extractions of medicinal plant raw materials - decoctions and infusions - are of a particular interest in this respect - as they are the most accessible and frequently used dosage forms in medical and pharmaceutical practice and traditional medicine, being at present insufficiently studied as sources of intake of various microelements in the human body. Objective: to investigate the peculiarities of heavy metals and arsenic trans-mediated transition along the chain "soil - medicinal plant raw materials - infusions and decoctions". Materials and methods. Raw materials were harvested during the flowering period in Voronezh Biosphere Reserve. The microelement composition of the samples was studied by mass spectroscopy on an ELAN-DRC device. Results. The content of toxic microelements estimated in medicinal plant raw materials of natural phytocenosis of Voronezh region does not exceed the pharmacopoeial requirements, and their total proportion in the total mineral complex - not more than 0.011%. All made infusions and decoctions from the studied raw materials infusions and decoctions also corresponded to pharmacopoeial requirements on the content of normalized elements. The efficiency of cadmium transfer in infusions and decoctions from medicinal plant raw materials ranged from 9.02% to 55.00%, arsenic - from 26.33% to 68.46%, lead - from 1.95% to 76.15%. In the chain "soil - medicinal plant material - water extracts" normalized elements in LRS to the greatest extent migrated to the decoction of burdock root: cadmium - 74.91%, arsenic - 13.98%, lead - 6.02%. The lowest degree of transition was noted for the infusion of the studied flowers: for cadmium - 4.78%, arsenic - 0.46%, lead - 0.73%. Conclusion. The findings are of great interest and may serve both for further research and for using in medical and pharmaceutical practice.

The genus Sisymbrium L. of Brassicaceae family has up to 90 species of single and perennial herbaceous plants growing in temperate regions of both hemispheres. In Russia there are up to 20 species, of which the most common is Sisymbrium officinale (L.) Scop. This species is widely used in traditional medicine around the world as an expectorant, restorative, diuretic, anthelmintic, for diseases of the digestive and respiratory systems. It is included in the Pharmacopoeia of France. However, it is not included in the State Pharmacopoeia of Russia; the pharmacopoeia article for medicinal plant raw materials has not been approved. The possibility of using a new species in scientific medicine makes it necessary to study the morphological and anatomical structure of the Sisymbrium officinale. Objective: to perform morphological (external) and anatomical (internal) analysis of the structural features of the reproductive organs (flowers and fruits) of the medicinal herb; to establish the signs by which it is possible to make a reliable diagnosis. Materials and methods. The study of morphological and anatomical features of reproductive organs (flowers and fruits) of Sisymbrium officinale was carried out in accordance with the articles of the State Pharmacopoeia of the Russian Federation of the XIV edition. Freshly harvested, dried and fixed raw materials were used for the study. Results. For the first time macro- and microdiagnostic signs of reproductive organs (flowers and fruits) of Sisymbrium officinale were described. Conclusion. For the first time macroscopic and microscopic signs of reproductive organs (flowers and fruits) of Sisymbrium officinale have been identified and described, which can be used to determine the authenticity of raw materials, as well as to develop sections «External signs» and «Microscopic signs» of modern regulatory documentation.