Using the author’s method for determining the multidimensional relationships of ionized calcium in personal observations in 82 patients based on the analysis of the panel of ratios of indicators of water and electrolyte metabolism, it was found that hypercalcemia in the structure of these ratios can include indicators of bone tissue metabolism, while differing in their characteristics. In the discussion, the authors cite modern literary sources that substantiate the established differences in the structure of complexes of multidimensional bonds. Also, the obtained results indicate the possibility of manifestation of signs of changes in the balance of B-cross Laps and TP1N with a high strength in combination with the influence of calcium, while maintaining the absolute values of the latter within the reference values of the norm. The authors believe that in these cases there are signs of a high functional stress of the mechanisms that contribute to maintaining analyte values within the normal range. Summarizing the results of the analysis of the selected observations, the authors believe that the mechanisms involved in the regulation of bone metabolism can be divided into two levels: local and intersystem (in particular, with the participation of leukocyte subpopulations). If the first level (primarily remodeling) weakly correlated with the influence of leukocyte subpopulations on this process, then the second, which was distinguished by significant shifts in the balance of osteosynthesis and osteolysis, included signs of activation of individual leukocyte subpopulations. In conclusion, the authors come to the conclusion that the use of the proposed method of visualizing multidimensional relationships makes it possible to determine the pathogenetic features of the formation of hypercalcemia in individual cases. At the same time, in the presence of a large database on electronic media, the technique for visualizing multidimensional relationships can be proposed as, at least, as an ‘express’ method for ‘recognizing’ different ‘images’ in the structure of the electrolyte ratio panel without actually determining osteomarkers and other complex and expensive methods for the determination of analytes that reflect osteoexchange.

The article defines reference values for activated partial thromboplastin time, Quick’s value, INR, thrombin time, fibrinogen, antithrombin and II, V, VII, VIII, IX, X, XI and XII coagulation factors, according to existing standards on the automated Sysmex CS‑2000i analyzer.

The aim of the study. To determine reference values for routine and specific parameters of the hemostasis, which may vary depending on the type of analyzer and utilized reagents.

Materials and methods. After receiving informed consent from donors for medical survey and blood donation, blood samples were obtained from 100 healthy donors: 64 (64%) males и 36 (36%) females. We established reference values with the Sysmex CS‑2000i (Sysmex, Japan) hemostasis analyzer and reagents from Siemens (Siemens Healthcare, Germany).

Results. The data obtained were compared with the literature data and the data presented in the instructions for the reagents used. The results obtained for activated partial thromboplastin time (23.59–35.69 sec), fibrinogen (1.67–3.59 g/l) and antithrombin (67.65–114.89%) are comparable to the available data. There are no data on other studied parameters of hemostasis for the Sysmex CS‑2000i analyzer and the reagents used in the work. The obtained reference intervals are consistent with the recommendations of the manufacturer.

Conclusions. Reference values vary significantly depending on the analytical systems and reagent kits used, which confirms the need for local derivation or validation of reference intervals for each specific analytical system and in each laboratory.

Introduction. Experimental model of intraperitoneal injection of sodium oxalate is one of the most promising and practical models of oxalate urolithiasis in rodents.

Purpose of the study. To describe the urolithiasis progression in experimental animals with regard to the changes in the ion balance at various stages of pathology formation.

Materials and methods. We treated male ICR (CD‑1) outbred laboratory mice with a single injection of sodium oxalate (NaOx) to perform nephrolithiasis modeling. The ionic composition of urine and blood serum in the control and experimental groups was examined by capillary electrophoresis. The presence of oxalate crystals in the urine sediment and histological data can assess the severity of the pathology.

Results and conclusions. Increase of the level of Na and Ca ions and decrease of the level of K, NH4, Mg ions was observed in 4 hours and 24 hours after intraperitoneal injection of sodium oxalate, that can be regarded as a depression of tubular reabsorption and secretion.

Chronic kidney disease (CKD) is one of the most common pathologies worldwide. With CKD, cardiovascular risk increases and mortality rises. The article presents the role of homocysteine as a laboratory marker of renal failure and the development of cardiovascular disease. Homocysteine is a thiol-containing amino acid, which is an intermediate product of methionine metabolism, which is metabolized in two ways: due to the transfer of the sulfate group, which occurs in the presence of vitamin B 6, or remethylation, which occurs in the presence of vitamin B 12 and folic acid. Normally, in an adult, the concentration of total homocysteine in blood plasma does not exceed 15 μmol/L. It has been shown that with CKD, hyperhomocysteinemia is observed at the initial stages and its frequency increases at the pre- and dialysis stages of the disease. Hyperhomocysteinemia provokes endothelial dysfunction, accelerates systemic atherosclerosis, increases the risk of atherothrombotic complications. Evaluation of plasma homocysteine levels may be useful in stratifying nephrocardio- and cerebrovascular risk in CKD.

Introduction. Previously, a domestic method for determining hepatitis B virus (HBV) genotypes and HBV surface antigen (HBsAg) subtypes in HBsAgpositive blood serum samples with a Monoclonal Antibody Panel (MAB) by enzyme immunoassay (ELISA) was described. In routine laboratory practice, HBsAg detection results are obtained in units of optical density (OD).

Purpose. To describe the sampling algorithm for ELISA geno- and subtyping of HBV with the MAB Panel.

Materials and methods. We studied 40 blood serum samples with positive results of HBsAg determination. HBV genotypes and HBsAg subtypes were determined using four different MAB conjugates with horseradish peroxidase using the ELISA method described previously.

Results. In samples with OD less than 2.0 o. u. and confirmation of HBsAg after a single confirmatory study (n = 19) HBV genotypes/ HBsAg subtypes not established. In samples with an OD above 2.0 o. u. and verification of the presence of the antigen in the standard mode of registration (n = 15), immunoenzymatic geno- and subtyping of HBV was effective in 27 % of cases (4/15); for samples with HBsAg verification carried out in an auxiliary measurement (n = 6) the effectiveness of the technique was 100 %. Using the MAB panel in ELISA, the characteristics of HBV in 10 samples with the presence of HBsAg were studied: HBV genotype D (n = 10), subtypes ayw2 (n = 7), ayw3 (n = 3).

Conclusions. For the most effective application of the HBV geno- and subtyping technique using the MAB Panel in ELISA, HBsAg+ samples with OD signals of more than 2.0 o. u. in screening and verification of the presence of an antigen in the auxiliary mode of registration of results should be used.

Relevance. Diseases of the circulatory system occupy a leading place in the structure of somatic pathology of liquidators. Obesity, signs of asthenization, vegetal vascular disorders, which were detected in numerous studies, suggest the presence of hypogonadism in this category of victims. Sex hormone deficiency is considered an important link in the formation of non-communicable diseases, which determined the relevance of the study.

The goal. To carry out a retrospective assessment of the change in the hormonal indicators of the endocrine axis of hypophysis-sex hormones and to assess the effect of partial androgen deficiency on the formation of circulatory diseases in the dynamics of the examination in the liquidators of the consequences of the Chernobyl accident.

Materials and methods. Hormonal indicators of the pituitary-gonadal endocrine axis were investigated by immunochemical analysis in 1065 men involved in the aftermath of the Chernobyl accident in 1986–1987, combined into groups depending on the period of examination from 1994 to 2019 and in control groups. The average age of patients entering the Chernobyl zone was 33.6 (0.8) years.

Results. Seven years after the accident, liquidators in 13.1 % cases show a shortage of sex hormones, by 33 years of follow-up, the proportion of such patients increases by 4.6 times. Sex hormone deficiency 7 years after the accident was revealed in men of relatively young age, the correlation of testosterone levels with the concentration of gonadotropins and prolactin has not been established. The increase in prolactin in the liquidators of the consequences of the Chernobyl accident, reliable in relation to the control group, remains for 12 years after the accident. 30–33 years after the accident, participants in the elimination of the consequences of the Chernobyl accident have significant age-related changes in hormonal indicators, among which the main is partial androgen deficiency.

Conclusions. The persistent imbalance of hormones of the pituitary-gonadal endocrine axis at the time of 1994–1998 contributed to the clinical manifestation of circulatory diseases in liquidators – middle-aged men, clinical symptoms, on the other hand, aggravated diverse shifts in the functioning of this endocrine axis of regulation. In the later period of observation by 30–33 years after the accident, a decrease in androgen levels was accompanied by a steady increase in circulatory diseases in liquidators.

Cigarette smoking has long been considered a risk factor for cardiovascular disease and a major preventable cause of death and disability in developed and developing countries. It is known that smoking can cause endothelial dysfunction and hemodynamic defects such as arterial stiffness. Among various surrogate markers of cardiovascular risk, arterial stiffness plays a central role and is a strong independent predictor of cardiovascular events, in addition to classical cardiovascular risk factors. This review presents the main mechanisms that explain the development of arterial stiffness during smoking, presents various treatment options for arterial stiffness as a therapeutic target for smokers with cardiorespiratory comorbidity.