Introduction. Healthcare-associated infections (HAIs) continue to pose a significant challenge to public health. The existing sterilization methods possess a number of limitations regarding their applicability to heat-sensitive materials and the possibility of residual toxicity or material damage. Sterilization using supercritical carbon dioxide, particularly in combination with oxidative additives, appears to be a promising alternative capable of providing the required level of microbial safety at low temperatures and moderate pressures. However, the available data show significant variability depending on experimental conditions, indicating the need for optimization and validation of processing regimes.

Objective. Optimization and validation of Bacillus subtilis spore sterilization regimes in an experiment using supercritical carbon dioxide (scCO₂), including pure scCO₂, scCO₂ with hydrogen peroxide (H₂O₂), and scCO₂ with peracetic acid (PAA).

Materials and methods. Experiments were conducted using a prototype test bench for investigating sterilization regimes. Bacillus subtilis subsp. spizizenii ATCC 6633 NCTC 10400 was used as the biological indicator. The study involved the contamination of titanium discs with spores followed by their treatment under the three regimes (pure scCO₂, scCO₂ + H₂O₂, scCO₂ + PAA). Further, microbiological analysis with enumeration of surviving spores and statistical processing of the results were carried out. For each regime, central composite experimental designs were implemented, varying temperature, pressure, and exposure duration. Efficacy was assessed based on the log-reduction of viable spores. Validation series included 10 independent replicates each.

Results. Gas-dynamic treatment with pure scCO₂ in the range of 35–60°C, 70–120 atm, and 60–120 min proved ineffective (maximum log-reduction ≤ 0.8). The addition of oxidizing agents significantly increased the degree of inactivation: for the scCO₂ + H₂O₂ (200 ppm) regime, the optimal parameters were 37.9°C, 120 atm, 30 min (log-reduction 4.4 ± 0.3; CV = 7.3%); for scCO₂ + PAA (50 ppm) — 45°C, 94 atm, 10 min (log-reduction 6.0 ± 0.3; CV = 4.9%), which meets the requirements for the sterility assurance level (SAL) for medical devices. The PAA regime provided a statistically significant higher efficacy compared to H₂O₂ (t-test, p < 0.001).

Conclusions. The sterilization methodology based on supercritical carbon dioxide with the addition of hydrogen peroxide or peracetic acid ensures effective inactivation of Bacillus subtilis spores under parameters compatible with the low-temperature processing of heat-sensitive medical materials, thus meeting modern sterility requirements for medical devices.

Introduction. Cohort analytical epidemiological studies of cosmonauts’ health have a number of specific features. The estimates of long-term health outcomes in this occupational group can only be refined provided that the observation period of the Soviet and Russian cosmonaut cohort, originally established in 2013, be extended and regularly updated with emerging data.

Objective. Analysis of changes in the main mortality indicators of Soviet and Russian cosmonauts over the cohort observation period extended by five years until 2023.

Materials and methods. Using prospective observation studies over the historically formed cohort of male Soviet and Russian cosmonauts in 1960–2023, data update was implemented. Encoded and anonymized personal data of cosmonauts underwent processing and analysis. Using the standardized mortality ratio (SMR) with a 95% confidence interval (95% CI), mortality risk among cosmonauts was assessed. The total number of participants as of the cohort closure date (31.12.2023) was 270 cosmonauts, divided into two groups based on the presence of spaceflight (SF) experience. Group 1 comprised 127 cosmonauts (47.0%), who undertook at least one SF. Group 2 comprised 143 cosmonauts (53.0%) without SF experience (internal control). The male population of Russia served as the external control group. Cause-of-death analysis was conducted according to ICD-10. Additionally, information on the initial education of cosmonauts as a factor significantly influencing life trajectory was collected. Statistical processing was carried out using the MS and Stata 14 software packages.

Results. Extending the observation period contributed to an increased accuracy of death risk metrics by narrowing the 95% confidence intervals. The all-cause mortality risk among cosmonauts with SF experience was found to be reliably lower compared to both the male population of Russia (SMR = 0.37; 95% CI 0.27–0.50) and cosmonauts without SF experience (SMR = 0.73; 95% CI 0.53–0.98). No statistically significant decrease in cancer-related death risk was observed among cosmonauts with SF experience compared to the general population (SMR = 0.62, 95% CI 0.32–1.09). A correlation was found between the initial education of cosmonauts and mean age at death. Thus, the mean age of death for cosmonauts with military specialization and SF experience was 68.1 years, compared to 60.3 years (p = 0.015) for those without SF experience.

Conclusions. Oncological vigilance in cosmonauts with SF experience is generally higher than in both control groups, despite their unequivocally better health status. Further refinement of the data obtained can only be achieved by extending the observation period, considering the career-long duration of space stay in relation to the health status of cosmonauts. Individual-related factors affecting the health of cosmonauts without SF experience were identified. The link between professional education and the mean age at death underscores the need for developing individual preventive measures for this group and longer post-career health monitoring.

Introduction. Assessment of the functional state of the respiratory system is a relevant task in the fields of sports, aerospace, and maritime medicine. Direct flowmetry methods cannot always be applied under conditions of a sealed enclosed environment. The recording and analysis of lung sounds appears to be a promising method for assessing the state of the respiratory system.

Objective. To assess the relationship between the amplitude characteristic of the recorded lung sound signal and the magnitude of pulmonary ventilation, as well as the applicability of the acoustic method for assessing the respiratory rate in healthy individuals during physical exercise, regardless of age and sex.

Materials and methods. The study involved 25 volunteers (20 male and 5 female) aged 23–59 years (mean age 35.5 ± 8.7 years). The participants were subjected to a stepwise increasing workload on an Ergoselect 200P cycle ergometer (Ergoline GmbH, Germany) up to submaximal heart rate levels, with simultaneous recording of respiratory sounds over the extrathoracic section of the trachea and measurement of respiratory flow via direct flowmetry using a Jaeger Oxycon Pro device. Statistical data processing was performed using the Statistica 13 software (StatSoft Inc., USA). To assess the relationship between respiratory sound power and pulmonary ventilation, a correlation analysis was conducted using Spearman’s rank correlation coefficient (r_s).

Results. During the study, the achieved maximum power output for all participants ranged 105–240 W; only two subjects were capable of developing a power level exceeding 210 W. Dependencies of respiratory sound power on pulmonary ventilation were obtained. Spearman’s rank correlation coefficient between the studied parameters was 0.58 (p < 0.001). Significant changes in the mean power of respiratory sounds were observed with an increase in load and pulmonary ventilation, already at the 30 W stage compared to the resting state (0 W) (p < 0.0001). The power of tracheal respiratory sounds also increased by 56% between the 120 W and 135 W load stages (p = 0.023) and by 75% between the 180 W and 195 W load stages (p = 0.043). No significant differences were found between respiratory rate assessments obtained by direct flowmetry and acoustic methods.

Conclusions. A statistically significant, moderate positive correlation was established between the magnitude of pulmonary ventilation and the mean power of respiratory sounds (r_s = 0.58; p < 0.001). For pulmonary ventilation values up to 60 L/min, the relationship between the mean power of tracheal sounds and pulmonary ventilation was found to be linear. A satisfactory agreement was determined between the acoustic assessment of respiratory rate and the data obtained by direct flowmetry methods. The analysis of respiratory sounds is capable of providing an indirect assessment of the state of the respiratory system.

Introduction. In the context of the COVID-19 pandemic, which has impacted all-cause excess mortality, it appears relevant to evaluate the synergistic effects of occupational radiation exposure and the SARS-CoV-2 infectious agent on the overall mortality in the population of a nuclear industry city. This is especially important for increasing the effectiveness of health protection and prevention measures among population and professionals.

Objective. A retrospective analysis of all-cause mortality rates in the population of the Ozersk urban district (OUD) during the COVID-19 pandemic, adjusted for the influence of radiation and non-radiation risk factors.

Materials and methods. A retrospective cohort study among residents of the Ozersk urban district who died from various causes in 2020– 2023 was conducted. Annual reports from Rosstat and the Municipal Statistics department were analyzed. Data on COVID-19 morbidity and mortality were provided by the Center for Hygiene and Epidemiology No. 71 in Ozersk. The survival function was assessed depending on COVID-19 status, with adjustment for age and external occupational radiation dose among workers of the Mayak Production Association, using the Kaplan–Meier method. The impact of COVID-19, considering occupational radiation dose, on all-cause mortality rates was analyzed using the Cox proportional hazards model.

Results. The analysis of mortality rate dynamics revealed the period associated with the peak of pandemic all-cause mortality in the OUD population. A significant influence of COVID-19 (p < 0.05) on all-cause mortality during the pandemic period, dependent on attained age and occupational radiation dose, was revealed. It was demonstrated that the pronounced effect of COVID-19 on all-cause mortality was a consequence of the multiplicative influence of several risk factors, among which attained age and external radiation dose had a significant impact.

Conclusions. The excess all-cause mortality rate in the OUD population during the pandemic period compared to the corresponding rate for the population of Russian Federation is a consequence of the impact of risk factors specific to population residing in the vicinity of nuclear industrial facilities. The results obtained are of interest for forecasting the potential detriment associated with the emergence of possible future pandemic situations.

Introduction. Computational phantoms are widely used for assessing radiation doses to the red bone marrow (RBM) from bone-seeking radionuclides. Among them, strontium isotopes are the most common. The development of phantoms for ^89,90Sr requires accurate description of bone shape, size, and microarchitecture. To date, phantoms for newborns, one-year-old, five-year-old, and 10-year-old children, as well as for adult males and females, have been proposed. This study is a continuation of our work on creating digital skeletal models for humans of different sexes and ages.

Objective. Development of computational phantoms for the skeleton for 15-year-old adolescents with the purpose of assessing doses in RBM from incorporated beta-emitting radionuclides.

Materials and methods. The phantoms were developed using the stochastic parametric skeletal dosimetry (SPSD) approach. Skeletal regions with active hematopoiesis were identified and segmented. The parameters of the segment models were estimated based on literature data, including bone microstructural characteristics, cortical bone layer thickness, bone and segment dimensions, the fractional content of RBM, and the chemical composition and density of the modeled media. The variability ranges of these parameters were also assessed.

Results. The developed phantoms for 15-year-old male and female adolescents comprise 46 segments each; parameters for 14 of these segments differed between males and females. The phantom dimensions ranged 3.5–66 mm; the cortical bone thickness varied 0.3–2.3 mm.

Conclusions. The phantoms developed in this work reflect the dimensions and structure of skeletal regions with active hematopoiesis in 15-year-old adolescents, account for sexual dimorphism, and simulate the variability of skeletal characteristics.

Introduction. Epidemiological studies suggest that ionizing radiation increases the risk of developing neurodegenerative diseases long after exposure; however, there is a notable lack of longitudinal studies and experimental research into establishing causal relationships between radiation dose and potential neurodegenerative effects.

Objective. The work investigates early and long-term alterations in sensorimotor parameters characterizing coordination in laboratory animals subjected to a range of doses of fractionated gamma irradiation at a young age.

Materials and methods. Experiments were carried out on mice of both sexes (n = 400) of the C57Bl/6 strain. Five observation groups were formed: two control groups and three groups with different radiation exposure levels, each made up of 80 individuals (40 males and 40 females). The animals underwent total external gamma irradiation during their first month of life at cumulative doses of 0.1 Gy, 1 Gy, and 5 Gy, with each dose divided into 20 fractions. The control groups of non-irradiated mice included: a group of intact animals serving as biological control (n = 80) and a sham-irradiation placebo group (n = 80). Evaluation of motor function is an effective tool for assessing symptoms of neurodegenerative diseases in animals. Coordination in irradiated and control animals was assessed using the tapered beam walking test at the ages of 1, 6, 12, and 18 months. Data were analyzed using Microsoft Excel and the R programming language.

Results. Sex and age were shown to influence sensorimotor parameters characterizing motor coordination (better in females, worsens with age in animals of both sexes), while no significant effect of the stress factor associated with animal irradiation was found on the studied parameters. A comparison of sex- and age-standardized sensorimotor parameters between irradiated animals and non-irradiated control mice revealed dose-dependent alterations. A deteriorated in motor coordination in the long term in mice exposed to gamma irradiation at a cumulative dose of 5 Gy manifested itself by a more than 1.5-fold increase in the number of errors compared to non-irradiated animals (t = 6.7; p << 0.001). Conversely, irradiation at a cumulative dose of 0.1 Gy produced an opposite effect: both in the early and long-term periods, the speed of mouse movement along the tapered beam increased relative to the non-irradiated control (walking time decreased by an average of 20% (p < 0.001) at any age), while in the early period, the number of errors also decreased (t = 2.36; p = 0.02), indicating an improvement in coordination ability.

Conclusions. Fractionated gamma irradiation at a young age induced dose-dependent alterations in sensorimotor function in animals: irradiation at a cumulative dose of 0.1 Gy resulted in improved coordination both in the early and long-term periods post-exposure; whereas irradiation at a cumulative dose of 5 Gy led to signs of impaired motor coordination in the long term, at 18 months of age.

Introduction. Up to 42% of young athletes who die suddenly show no signs of known cardiac diseases at autopsy (such as cardiomyopathies, myocarditis, or congenital heart defects). However, molecular genetic analysis in young sudden death victims identifies mutations in genes responsible for Long QT Syndrome (LQTS) in 17–23% of cases. During comprehensive medical examinations (CME) of young athletes in Russian national teams within the FMBA of Russia system, up to 24% of athletes are disqualified from sports due to detected QT interval prolongation for further diagnosis, with the diagnosis of LQTS being confirmed in 0.24% of cases.

Objective. Analysis of diagnostic methods for LQTS in young athletes and criteria for their clearance for sports training.

Discussion. The pathogenesis of LQTS is based on genetically determined impairment of cardiac ion channel function, which causes myo- cardial electrical instability predisposing to cardiac events. Such events include Torsades de Pointes (TdP) ventricular tachycardia, syncope, cardiac arrest, and sudden cardiac death (SCD). Diagnosis of LQTS is based on the Schwartz criteria, which incorporate data from standard ECG (QTc > 450 ms), Holter monitoring (HM), stress tests, clinical presentation, and family history. A score of more than three points based on these criteria makes the diagnosis of LQTS highly probable. According to international criteria for QT interval assessment in adult athletes, the proposed upper limits of normal QTc duration are up to 470 ms for males and up to 480 ms for females. Some authors suggest that QTc val- ues up to 500 ms may be acceptable in athletes; however, according to the Schwartz criteria, this value is sufficient to confirm the diagnosis of LQTS. Bradycardia, typical of trained athletes, is another LQTS criterion in pediatric ECG assessment. Methods for QT assessment during bradycardia in young athletes are not specified. Intense training may increase QT interval duration; conversely, temporary detraining may lead to its decrease. The Schwartz criteria based on HM results include only T-wave alternans and TdP tachycardia. QT interval assessment during HM remains a subject of debate. To date, at least 17 pathogenic genes responsible for LQTS have been identified. Detection of Class IV–V pathogenic mutations is sufficient for diagnosing LQTS, regardless of QT duration. The issues of clearance/return to sport-specific training for athletes with LQTS remain controversial, being addressed differently across countries. There are known cases of athletes with LQTS who have achieved significant success in sport competitions, as well as regular occurrences of SCD in young individuals with this condition. Current Russian and international guidelines state that competitive sports are contraindicated for patients with confirmed LQTS.

Conclusions. The assessment of the QT interval in young athletes involves numerous methodological and clinical peculiarities distinct from those in non-athletic individuals. Underestimating these peculiarities can lead to over- or under-diagnosis of LQTS, thereby potentially creat- ing a life-threatening situation for the athlete. Individual risks in different categories of LQTS patients are composed of multiple components. Disqualification from sports does not eliminate the risk of cardiac events in LQTS; at the same time, the extent to which sports activity itself increases these risks remains unknown today. This underscores the relevance of actively studying and clarifying these unresolved issues in young athletes with QT interval prolongation and LQTS.

Introduction. Previous research has demonstrated the high efficacy of peripheral magnetic stimulation (PMS) in the postoperative period of athletes for increasing strength and muscle tissue hypertrophy. Scientific and experimental substantiation for the use of PMS within the medical and biological support system for elite sports to improve the functional capabilities of the musculoskeletal system (MSS) in healthy athletes represents a relevant research task.

Objective. Study of the effect of rhythmic PMS on the functional capabilities of MSS in male athletes.

Materials and methods. The study was conducted at the Yug-Sport Rehabilitation and Recovery Center for Athletes in Kislovodsk (Russia). In total, 38 highly qualified male athletes were involved, who were divided into three groups: experimental group 1 (EG1) — 15 individuals, experimental group 2 (EG2) — 8 individuals, and the control group (CG) — 15 individuals. PMS was administered using a BTL-6000 Super Inductive System high-intensity magnetotherapy device, following two protocols for modulation and stimulation frequency. In the athletes, the following parameters were assessed: electrophysiological studies (electroneuromyography), rheovasography, and dynamometry of the lower limbs. These assessments were conducted before the intervention, after the first session, and after a course of eight PMS treatment sessions. In the control group, PMS was not applied. All parameters in this group were measured before and after the training camp period.

Results. The application of PMS to the posterior aspect of the left and right thigh at an intensity above the motor threshold (25–80%) and a frequency modulation of 1–150 Hz (EG1) contributed to a decrease in latency parameters and an increase in motor conduction velocity, as well as the M-response amplitude and area upon stimulation of the peroneal nerve. The application of PMS to the same area and at the same intensity, but with a frequency modulation of 1–50 Hz (EG2), increased the M-response amplitude and area. An increase in peripheral hemodynamics in the vessels of the lower limbs and in the strength parameters of the hip flexor and extensor muscles was revealed, along with an improvement in intermuscular coordination.

Conclusions. The application of PMS in highly qualified athletes contributes to an increase in the functional capabilities of MSS, manifested in improved parameters of neuromuscular transmission, peripheral hemodynamics, and strength capabilities.

Introduction. The problem of intermediate syndrome following anticholinesterase poisoning remains poorly studied. This syndrome is clinically manifested as a myasthenic condition developing after the cholinergic crisis, affecting the muscles of the face, neck, proximal limbs, and respiratory muscles. The current literature describes limited attempts to use non-depolarizing muscle relaxants for the prevention and treatment of this condition. However, given the diversity of mechanisms underlying toxic myasthenia in anticholinesterase poisoning and the low safety profile of non-depolarizing muscle relaxants, research into the effective and toxic doses of these drugs is highly relevant for establishing the principles of their use in correcting neuromuscular transmission disorders.

Objective. To experimentally evaluate the efficacy of pancuronium bromide, a non-depolarizing muscle relaxant, in correcting neuromuscular transmission impairments in cases of anticholinesterase poisoning.

Materials and methods. Experimental, two-stage studies were conducted using male outbred white rats weighing 220–250 g (n = 78). Initially, pancuronium bromide was administered subcutaneously to intact animals to determine effective doses. The severity and duration of the muscle relaxant effect were assessed using clinical and functional tests (hanging on a horizontal bar, assessment of movement impairments according to the De Bleecker scale), and electromyography (single and rhythmic stimulation at 30 Hz). Subsequently, therapeutic doses of the drug were determined in a rat model of fenthion poisoning (12 h after its single subcutaneous administration at an LD₅₀ dose of 479.4 mg/kg) based on data from the aforementioned methods and evaluation of changes in animal mortality rates. Statistical analysis of the results was performed using non-parametric statistical methods in the Prism GraphPad 9.0 software environment.

Results. Based on the assessment of neurological status and electromyography results, the median effective dose (ED₅₀) of pancuronium upon subcutaneous administration in intact rats was found to be 238.0 [95% CI: 219.8; 257.7] μg/kg. In contrast, against the background of severe fenthion poisoning, its therapeutic dose was statistically significantly lower (p < 0.05, Student’s t-test), amounting to 90.1 [95% CI: 77.3; 105.1] μg/kg. Similar trends were observed for the median lethal doses (LD₅₀) of pancuronium bromide: 321.1 [95% CI: 305.8; 337.1] μg/kg and 152.3 [130.6; 177.6] μg/kg, respectively. Administration of pancuronium at the median therapeutic dose reduced the severity of the myasthenic syndrome induced by fenthion poisoning, manifesting as restored muscle strength and normalized electrophysiological characteristics of neuromuscular transmission.

Conclusions. The experiment demonstrated that pancuronium bromide can be used to correct neuromuscular transmission disorders underlying the intermediate syndrome emerging as a result of anticholinesterase poisoning. The effective dose for this correction is 90.1 μg/kg, which is 2.6-fold lower than the effective dose for healthy animals (238.0 μg/kg). The main electrophysiological criteria for the regression of the neuromuscular block should include a reduction in the number of repeated M-responses and the restoration of the decrement-increment pattern of the M-response series, which persist for 1 h after pancuronium bromide administration.

Introduction. As a rule, preclinical safety assessment of narcotic analgesic agents is conducted at ambient temperatures of 20–24 °C. However, their clinical use may occur under different thermal conditions. Previous studies have demonstrated the ability of heat stress to potentiate the lethal and narcotic effects of fentanyl in rats, yet the mechanisms underlying this phenomenon remain unknown.

Objective. Testing hypotheses on the mechanisms of fentanyl toxicity potentiation in rats under heat stress conditions.

Materials and methods. The study was conducted on outbred male albino rats weighing 191–210 g. We investigated the effects of intravenous fentanyl administration at a dose of 200 μg/kg and/or a 40-min exposure to an ambient temperature of 40 °C on body temperature and mass, brain moisture content and mass, glutamine concentration in brain tissue, biochemical parameters of blood collected from the a. carotis communis and v. jugularis interna, and oxygen consumption by brain homogenates. Statistical analysis was performed using the OriginPro software.

Results. Fentanyl administration induced opisthotonus, coma, bradypnea, and fundal cyanosis. The 40-min lethality following fentanyl injection was 0–9% at an ambient temperature of 22 °C and 68–71% at an ambient temperature of 40 °C. In surviving rats removed from the thermal chamber, rectal temperature was elevated to 42.9 °C. The relative mass of the freshly isolated brain and the brain dried to a constant weight increased by 7.4% and 7.2%, respectively. Glutamine content in brain tissue increased by 46%. Plasma concentrations of ammonia, creatinine, and lactate were elevated by 2.0–2.2, 2.1–2.3, and 1.5–1.6 times, respectively. In the absence of fentanyl administration, no lethality was observed in rats placed in the thermal chamber. Rectal temperature increased to 42.7 °C. The relative mass of the freshly isolated brain and the dried brain increased by 6.1% and 8.9%, respectively. Brain glutamine content increased by 43%. Plasma creatinine levels rose by 2.2–2.4 times, and lactate levels increased by 25–45%. In the absence of heat stress, fentanyl increased plasma creatinine concentration only by 1.6–1.8 times. The arteriovenous gradient of plasma ammonia concentration was positive in all animals. Oxygen consumption by brain homogenates decreased by 10% under isolated heat stress and increased by 7% under a combined action of heat stress and fentanyl administration.

Conclusions. Hypoxemia, lactic acidemia, and hyperammonemia were necessary conditions for the aggravating effect of heat stress on acute fentanyl intoxication in rats. Conversely, irreversible thermal damage to biological tissues, organism dehydration, cerebral edema, swelling, hyperemia, and glutamine accumulation in the brain were not identified as such necessary conditions.

Introduction. The use of aromatic anticonvulsants (carbamazepine, oxcarbazepine, lamotrigine, and phenytoin) is associated with the risk of severe hypersensitivity reactions, which are partly dependent on HLA-B and HLA-A genotypes (for carbamazepine/oxcarbazepine). Phenytoin and fosphenytoin are metabolized by CYP2C9; therefore, in the setting of genetically determined impaired drug tolerability, the likelihood of adverse events increases. Consideration of the CYP2C9 genotype is important for developing personalized drug dosing schemes and improving treatment outcomes.

Objective. Assessment of the prevalence of major pharmacogenetic variants associated with response to aromatic anticonvulsants, with geographic stratification and identification of at-risk populations warranting preemptive genotyping prior to treatment initiation.

Materials and methods. The study was performed using samples from the Population Frequency Database (GDB) of the Federal Medical and Biological Agency (FMBA) of Russia (n = 120,979, covering 82 RF subjects). Whole-genome sequencing of DNA samples was conducted followed by an analysis of the carrier frequency of HLA-B*15:02, HLA-B*15:11, HLA-A*31:01, and various allelic variants of CYP2C9 with calculation of the enzyme activity score. These metrics were compared across different Russian regions, identifying high-risk biogeographic groups.

Results. The HLA-B*15:02 variant showed a prevalence of less than 1% in all regions of the Russian Federation. A relatively high carrier frequency of HLA-B*15:11 was observed in the Republics of Buryatia and Tyva (1.3%, p = 7.7 × 10^–5 and 3.46%, p = 2.4 × 10^–3, respectively, compared to a population frequency of 0.11%). The elevated frequencies of HLA-A*31:01 were detected in Perm Krai and the Republics of Kalmykia, Buryatia, Tyva, and Sakha (Yakutia) (8.48%, p = 0.042; 8.79%, p = 0.044; 10.3%, p = 3.4 × 10^–10; 20.44%, p = 3.4 × 10^–10; 28.74%, p = 5.4 × 10^–122, respectively, compared to a population frequency of 5.06%). The Republics of Dagestan, Ingushetia, and Kabardino-Balkaria showed a higher prevalence of impaired metabolism phenotype for phenytoin/phosphenytoin (46.4%, p = 5.6 × 10^–36; 44.69%, p = 1.7 × 10^–13; 43.83%, p = 1.9 × 10^–16), primarily due to a high frequency of the CYP2C9*3 allele. The Republics of Tatarstan, Mari El, and Chuvashia were also characterized by a high incidence of alleles associated with impaired metabolism of these drugs (37.06%, p = 0.028; 37.99%, p = 0.031; 41.2%, p = 5.3 × 10^–10), attributable to the presence of the generally rare CYP2C9*29 allele in their genetic structure.

Conclusions. The results obtained enable the formulation of region-specific recommendations for personalizing treatment with aromatic anticonvulsants. For residents of Sakha (Yakutia), Tyva, Buryatia, Kalmykia, and Perm Krai, testing for HLA-A*31:01 carriage is justified. For residents of Tyva and Buryatia, additional testing for HLA-B*15:11 carriage is warranted prior to the prescription of carbamazepine and oxcarbazepine. Before initiating phenytoin therapy, CYP2C9 genotyping is particularly important for the populations of Dagestan, Ingushetia, Kabardino-Balkaria, Tatarstan, Mari El, and Chuvashia. However, this genotyping can be recommended for the entire population of Russia due to the high prevalence of alleles associated with reduced and absent enzyme activity. 

Introduction. The development of hydrogel coatings is a promising research direction in burn injury therapy. Honey-based hydrogels possess unique physicochemical characteristics due to being transparent, capable of effectively absorbing exudate, and exhibiting low pH values. All these properties make them ideal candidates for application not only in cosmetology but also in medicine for the transdermal delivery of various medicinal substances.

Objective. Synthesis of honey-based hydrogels and comparative analysis of their physicochemical characteristics and antibacterial activity.

Materials and methods. Hydrogels were synthesized based on chitosan and сarbopol with addition of 25, 50, and 75 wt % of white honey. The following parameters were investigated: viscosity (using a Brookfield rotational viscometer); spreadability (by a compression method); degree of sample swelling; stability (by centrifugation); honey release from the sample (using an ERWEKA DT-820 tester); analysis of the quantitative honey content in the buffer (by spectrophotometry). The study of in vitro antibacterial properties was conducted using Candida albicans ATCC 64550 (a yeast-like fungus), Staphylococcus aureus ATCC 25913 (a gram-positive bacterium), Escherichia coli ATCC 25922 (a gram-negative bacterium), Acinetobacter baumannii 897 (a gram-negative bacterium), Enterobacter cloacae ATCC 13047 (a gram-negative bacterium), Klebsiella pneumoniae ATCC 19606 (a gram-negative bacterium). Statistical data processing was performed using the DeltaX 3.0 software.

Results. In terms of viscosity, the hydrogel based on 1% Carbopol 940 with a honey concentration of 25 wt % outperformed other gels. The samples based on 1% Carbopol ETD 2020 with a honey concentration of 50 wt % exhibited the lowest spreadability. The highest sorption capacity 1 h and 3 h after the onset of testing was demonstrated by the sample based on 3.5% low-viscosity chitosan with a honey concentration of 25 wt %. The highest honey release was shown by the sample based on 10% low-viscosity chitosan with a honey concentration of 50 wt %.

Conclusions. The conducted study of physicochemical and antibacterial properties render chitosan-based hydrogels promising for further investigation. Hydrogel samples with a 75% honey concentration failed the stability test, which make them unsuitable for use as a therapeutic delivery system. Based on the results obtained, a mixed hydrogel based on Carbopol 940 and 3.5% low-viscosity chitosan is recommended for further research.

Introduction. 5-Hydroxyiminobarbituric (violuric) acid and its derivatives exhibit pronounced anti-hypoxic, hepatoprotective, cytoprotective, actoprotective, and other properties, making this group of compounds a promising field for pharmaceutical research. Data on the metabolism of violuric acids (VAs) are of significant practical and theoretical importance for the tracking of pharmacokinetics and substance distribution within the organism, in which process metabolites serve as markers of biochemical processes involving endogenous substrates.

Objective. To determine the structure of violuric acid metabolites and perform their quantitative assessment in an in vivo experiment.

Materials and methods. The studied substances (VAs) and their metabolites (purpuric acids) were synthesized at the Golikov Research Center of Toxicology. Their structure and purity were confirmed by nuclear magnetic resonance (NMR) spectroscopy, high-performance liquid chromatography (HPLC), and spectrophotometry (SP). Metabolism and anti-hypoxic activity were studied using a model of hemic hypoxia induced by a lethal dose of sodium nitrite in outbred male white rats. Solutions of violuric acids for in vitro studies and administration to animals were prepared in distilled water with the addition of tris(oxymethyl)aminomethane (TRIS), while purpurates in the form of salts were dissolved in distilled water. The dosages of the test substances for rats ranged from 50–75 mg/kg for intraperitoneal administration and 50–100 mg/ kg for intragastric administration. The reference substance (amtizole succinate) was administered to animals at a dose of 100 mg/kg. A 0.9% sodium chloride solution, administered at a volume of 1 mL per animal, was used as a control. Quantitative analysis of the substances and their metabolites in biological media was performed by HPLC with SP detection.

Results. It was established that the studied substances (violuric acid, 2-thiovioluric acid, 1-butylvioluric acid, and 1-(4-bromophenyl)violuric acid) are metabolized in the animal organism to form the corresponding derivatives of purpuric acid (purpurates), whose structure was confirmed by counter synthesis. Violuric acids and their metabolites are primarily excreted in the urine. It was demonstrated that 1-butylvioluric acid and its metabolite N,N’-dibutylpurpuric acid exhibit pronounced anti-hypoxic activity in the model of acute sodium nitrite poisoning, preventing mortality in 100% of animals, whereas the reference antihypoxant amtizole only prolongs survival time (by 23%).

Conclusions. The formation of purpurates is a characteristic pathway of metabolic transformation for the violuric acid scaffold. These metabolites exhibit pronounced activity and, in all likelihood, can contribute to the overall biological effect of violuric acids.

Introduction. Genetic data, which are subject to legal protection, require the creation of specialized legislative acts regulating the collection, processing, and storage of such information. The development of a conceptual framework that could take into account the diversity of genetic data types and their application purposes represents a relevant task.

Objective. Determining directions for the development of a regulatory framework governing the circulation of human genetic data in the Russian Federation based on an assessment of the current state of legal regulation in this field.

Discussion. All types of genetic information are subject to legal protection according to their significance. In terms of current terminology, such concepts as “genetic information” and “genetic data,” require clarification. The Russian legislation is currently lacking a regulatory document governing the circulation of genetic data and genetic information obtained from humans. Foreign experience demonstrates active adoption of specialized legal acts protecting genetic information. Active development of biobanks and databases of genetic information requires clear legislative algorithms for data protection. In cases of anonymized data stored in databases, personal or medical data protection regimes become impractical. Thus, databases should occupy a separate position in the legal landscape. Issues regarding the regulation of creation, storage, and dissemination of genetic data repositories remain unresolved. Approaches to protecting and securing individual-level genetic information (in the context of medical care or private use) and safeguarding anonymous genetic data banks (for research purposes) should be delimited.

Conclusions. The existing disparity between the current advances in genetic technologies and legislation governing the generated data can be resolved by introducing new legislative initiatives and enacting laws that take into account the knowledge of modern biomedical science.

Introduction. Cardiovascular diseases (CVD) are the leading cause of mortality in the Russian Federation. Existing healthcare programs are primarily focused on the treatment of manifest CVD, while the prevalence of genetic risk factors (cardio-germline variants) remains understudied.

Objective. Assessment of the prevalence of pathogenic and likely pathogenic (P/LP) cardio-germline variants in Russian population based on a representative sample.

Materials and methods. The study was conducted using samples from the Genetic Database (GDB) cohort of the Centre for Strategic Planning (FMBA of Russia), comprising 116,794 participants from 86 Russian regions. Whole-genome sequencing (WGS, coverage >30x) of DNA was performed (database of the Centre for Strategic Planning FMBA of Russia). The search and annotation of pathogenic and likely pathogenic (P/LP) variants in 37 genes associated with CVD were performed based on ClinVar. Statistical analysis was conducted using Python (v3.9.12).

Results. P/LP variants in 26 genes were identified in 0.98% (1152) of participants (cumulative allele frequency 0.49%, 424 unique variants). The prevalence by disease groups was as follows: hypercholesterolemia — 0.1704%, structural abnormalities — 0.2218%, arrhythmias — 0.1040%. The most frequent variant was rs5742904 (APOB gene, 0.0545%). When strictly considering only variants with the “reviewed by expert panel” level of evidence (Level A), the prevalence was 0.14%. Significant geographical variations were observed (ranging 321–6250 carriers per 100,000 population), with the highest frequencies in the Chechnya, Khakassia, and Bryansk Oblast. No statistically significant decrease in the proportion of carriers was found in the age group over 75 years, confirming the generally low penetrance of these variants. However, within the group over 75 years, a higher number of carriers was observed among female compared to male subjects (p = 0.013), which may indicate a greater effect of these variants on male carriers.

Conclusions. The study has identified for the first time a significant “hidden burden” of P/LP cardio-germline variants (~1% carriers) in the Russian population. The substantial geographical variations underscore the importance of a regional approach to healthcare resource planning. The absence of an overall decrease in carrier frequency among the elderly, combined with sex-specific differences in age-related dynamics for certain disease groups, highlights the role of modifying factors and variable penetrance. The data obtained are critical for the development of preventive cardiogenetics and the optimization of the CVD prevention system in Russia.

Introduction. Cancer is a leading cause of mortality worldwide. Hereditary (germline) mutations in cancer predisposition genes significantly contribute to oncogenesis (accounting for 3–12.6% of adult cases). Identifying carriers of pathogenic/likely pathogenic (P/LP) variants is crucial for cancer prevention and its early detection. Large-scale data on the prevalence of such variants in the general population of the Russian Federation, essential for healthcare resource planning, have been extremely limited until now.

Objective. To assess the prevalence and spectrum of pathogenic and likely pathogenic germline variants in genes associated with cancer risk in a Russian population cohort.

Materials and methods. An analysis of whole-genome sequencing data from 116,794 participants (a representative sample of the adult population from 86 federal subjects of the Russian Federation) was conducted. The search for P/LP variants in cancer-associated genes was performed based on the ClinVar database. Variant annotation was carried out considering the level of evidence. Statistical analysis was performed using Python (v3.9.12).

Results. P/LP variants were identified in 26 cancer-associated genes among 2643 participants (2.26%). The most frequent variant was rs36053993 (MUTYH, 0.28%), with its frequency in the Russian Federation being lower than in global databases (ALFA, gnomAD). Level A variants (only those with the “reviewed by expert panel” level of evidence) were carried by 0.8% of individuals collectively. Level B variants (those with the “reviewed by expert panel” and “criteria provided, multiple submitters, no conflicts” levels of evidence) were carried by 2.08%. The inclusion of less reliable evidence levels (C, D) increased this proportion only marginally, to 2.26%. A statistically significant decrease in the proportion of carriers of Level A variants with age was observed (p = 0.007), while the overall proportion of P/LP variant carriers decreased only slightly (p = 0.17). Substantial geographical variability in prevalence was identified, ranging from 865 (Bashkortostan) to 6250 (Chechnia) variants per 100,000 population. In Moscow, the prevalence was 2340 per 100,000.

Conclusions. The study revealed a significant “hidden burden” of P/LP oncogenic germline variant carriers (2.26%) in the Russian population. The primary burden is attributed to variants with a high level of evidence (Level B). The substantial variability in prevalence across regions of the Russian Federation necessitates a differentiated approach to healthcare resource planning. The data obtained substantiate the need for implementing genetic screening programs (especially for individuals with a family history) and enhanced oncological surveillance for carriers. This represents a strategic direction for reducing cancer incidence and mortality in high genetic risk groups within the Russian Federation.

Introduction. Determination of the CYP2C9, CYP2C19, and CYP2D6 genotypes enables therapy personalization for a wide range of medications. The currently available diagnostic panels and international guidelines governing the scope of testing are based on global data concerning the allelic polymorphism of these genes.

Objective. To determine the distribution of allelic variants of the CYP2C9, CYP2C19, and CYP2D6 genes in the population of the Russian Federation, taking regional characteristics into account.

Materials and methods. The study was conducted on a sample from the Genetic Database (GDB) of the Centre for Strategic Planning and Management of Biomedical Health Risks (n = 121,442, covering 85 Russian federal subjects). Whole-genome DNA sequencing was performed for all participants, with CYP2C9, CYP2C19, and CYP2D6 genotyping determined using the PAnno software. In regions with a sufficient number of observations, variant frequencies and the proportions of different metabolic phenotypes were compared, identifying high-risk regions and those with an allelic structure differing from the overall population.

Results. The prevalence of impaired metabolism for CYP2C9 substrates in the population is estimated at 33.66%, for CYP2C19 at 25.37%, and for CYP2D6 at 8.29%. The prevalence of accelerated metabolism for CYP2C19 substrates is 37.37%. The following regions are identified as high-risk for the presence of impaired metabolism of substrates for at least one of the studied isoenzymes: the Republics of Chechnya, Dagestan, Ingushetia, Kabardino-Balkaria, North Ossetia, Chuvashia, Mari El, Udmurtia, Tatarstan, Tyva, Sakha (Yakutia), Kalmykia, Buryatia, Karelia, as well as Rostov Oblast, Sakhalin Oblast, Irkutsk Oblast, and Novosibirsk Oblast. This risk manifests due to both quantitative differences in the frequency of common allelic variants and the presence of rare alleles in specific regions, such as CYP2C9*29, CYP2C9*12, CYP2C19*8, CYP2D6*32, and CYP2D6*7.

Conclusions. The obtained results provide the basis for the development of domestic diagnostic panels and for implementing a differentiated approach to pharmacogenetic testing across various biogeographic groups within the country. The introduction of such panels must be accompanied by health economic evaluation for each drug whose effectiveness and safety depends substantially on the CYP2C9, CYP2C19, and CYP2D6 genotype.

Introduction. Recent observations indicate that craniofacial injuries can present as isolated, multiple, or combined trauma. Currently, there is a lack of objective criteria for determining impairments of vital functions that necessitate specialized, multidisciplinary medical care at Level I trauma centers, including multistage surgical treatment (MST) as a criterion for comprehensive management. Furthermore, criteria and indications for the comprehensive treatment of combined injuries, which account for up to 80% of cases, have not been developed in sufficient detail.

Objective. Development of a rational multistage surgical treatment (MST) protocol for combined trauma that takes into account injury severity and impaired body functions in patients with midface injuries.

Materials and methods. A total of 132 patients were examined, with males comprising 84.8% (n = 112) and females comprising 15.2% (n = 20). The age distribution of the patients was as follows: males aged 20–39 years — 44.7% (n = 59), males aged 40–59 years — 40.1% (n = 53); females aged 20–39 years — 1.5% (n = 2), females aged 40–59 years — 13.6% (n = 18). All patients were divided into three groups: Group 1 — 40 patients (30 males; 10 females) with a compensated course (trauma disease (TD) Type I); Group 2 — 44 patients (38 males; 6 females) with a subcompensated course (TD Type II); Group 3 — 48 patients (44 males; 4 females) with a decompensated course (TD Type III). The study outcomes were assessed based on injury severity and impaired body functions. Injury severity was evaluated using the Trauma Shock Potential Scale (Tsibin), the Military Field Surgery — Injury Scale (MFS-I), and the Abbreviated Injury Scale (AIS). Impaired body functions were evaluated using MFS-SE (State Upon Entry), MFS-SA (State After Admission), and MFS-SS (Specialized State) scales. Statistical data processing was performed using the Statistica 10 software package. Standard descriptive statistics were calculated (mean [M], standard deviation [SD], median [M_e], lower [Q₁] and upper [Q₃] quartiles). Hypothesis testing for the equality of means was assessed using Student’s t-test.

Results. The conducted analysis of statistical data on the nature of injuries and impaired vital body functions allowed an MST methodology to be developed. Its application enabled adequate administration of specialized resuscitative care in 90% of cases, as well as multidisciplinary surgical care. For Group 1 patients, MST was primarily provided on an abbreviated basis, without performing a tracheostomy or gastrostomy, followed by a full-scale surgical intervention during the first period of TD. Treatment for patients in Groups 2 and 3 was initiated in a shock room or an intensive care unit (ICU).

Conclusions. In cases of TD Type I, i.e., isolated maxillofacial injury with a compensated course, the principles and algorithms of the general therapeutic and tactical approach to TD management are not applicable, and the full scope of surgical interventions can be performed during the first period of TD. In cases of TD Types II and III, the full scope of MST should be implemented.

Introduction. The development of the Arctic zone of the Russian Federation implies the operation of offshore structures under extreme climatic conditions, high industrial hazards, and remoteness from onshore infrastructures. In such a context, provision of efficient medical care becomes of strategic importance. However, personnel training for health posts on offshore structures remains insufficient. In addition, there is no professional standard for a “shipboard medical specialist,” with the existing qualification requirements covering only a portion of all necessary competencies.

Objective. To analyze and generalize the regulatory, organizational, and personnel requirements for medical staff at health posts of offshore structures on the Arctic Shelf, and to develop proposals for improving their training system.

Materials and methods. The study was conducted using an analytical retrospective design. The research base included the regulatory legal acts of the Russian Federation (2010–2025), orders of the Ministry of Health, the Ministry of Labor, and the FMBA of Russia, corporate regulations of two oil and gas companies, as well as medical evacuation statistics. Methods of analytical review and content analysis were applied.

Results. Staff shortages and the lack of specialized training were established as the limiting factors in the sustainable functioning of the entire system. The necessity of a multi-level training model was substantiated, including mandatory qualification requirements, regular simulation trainings, specialized courses and introductory courses for physicians, as well as the requirement for certificates permitting physicians to work.

Conclusions. Regular additional training and the formation of a unified registry of physicians who have completed the full training program are key conditions for ensuring the medical safety of remote facilities in the Arctic zone of the Russian Federation and for developing the personnel potential.

Introduction. Laboratory production of viral material in small quantities is performed, as a rule, using adherent cell lines and culture flasks of varying surface area. The need to increase product yield leads to either an increase in the number of flasks or a switch to other accumulation systems, such as roller bottles. One factor influencing the efficiency of cell adhesion and homogeneous monolayer formation is the rotation frequency of the roller bottle. There is a lack of available research data on the impact of rotation frequency on these parameters and determination of its optimal value, particularly based on cellular morphology.

Objective. To optimize the initial stage of roller cultivation for Vero and HEK293 cell lines, taking into account the effect of roller bottle rotation frequency on cell adhesion during seeding and monolayer formation.

Materials and methods. Experiments were conducted using two monolayer cell lines, Vero and HEK293. Seeding concentrations were taken from the cell line passports, amounting to 4×10⁴ cells/cm². Each cell line was seeded onto roller bottles and cultured according to the range of rotation frequencies (0.2, 0.3, 0.4, 0.5, and 0.6 rpm) using a Celrol Mid roller (Wiggens) in a RWD D180 CO₂ incubator. Following 1, 2, and 3 days of cultivation, the quality of cell adherence to the growth surface and monolayer formation was assessed by a TC5400 microscope (Meiji Techno).

Results. During cultivation of the Vero cell line, the rotation frequency up to 0.6 rpm did not significantly affect cell adhesion to the surface. The most homogenous cell distribution was observed at rotation frequencies of 0.4–0.5 rpm. The HEK293 cell culture is more sensitive to mechanical disturbances of the nutrient medium; as a result, at rotation frequencies above 0.2 rpm, abnormally rounded cell shapes and impaired adherence to the growth surface were observed. Furthermore, continued cultivation at this rotation frequency did not lead to the formation of a homogenous monolayer due to slow alternation between the respiration and nutrition phases. Consequently, after cell adherence to the surface, the rotation frequency of the roller bottle should be increased. 

Conclusions. For the Vero cell line, the optimal rotation frequency was established to be 0.4–0.5 rpm. For the HEK293 cell line, the rotation frequency should be at least 0.2 rpm during the first day followed by its increase to 0.5 rpm after 24 h. The tested cultivation conditions enable an efficient growth of these cell lines for the production of viral biomass.

Introduction. Telomere length is considered a potential biomarker for individual human radiosensitivity and radioresistance. Radiation exposure can both increase and decrease the average telomere length in cells, while the lengths of individual telomeres vary widely. The assessment of ultra-short and ultra-long telomere frequency may indicate alterations in the replicative potential of cells and radiation-induced genomic instability.

Objective. To investigate the relative telomere length using the Q-FISH method in exposed individuals and to identify the proportion of ultra-short and ultra-long chromosomal telomeric regions in this cohort.

Materials and methods. The study involved 43 volunteer donors (women) from different age groups (21–28; 60–67; and 71–83 years). At stage I, an investigation of the dose-dependence of relative telomere length was performed in the control group. The donors were divided into groups: younger (n = 4) — non-exposed women aged 21–28 years; middle-aged (n = 12) — women aged 60–67 years; older (n = 5) — women aged 71–83 years. At stage II, the reference for average telomere length was established using donors (n = 5) from the older age group. At stage III, considering the established reference values, telomere length was studied in exposed individuals (n = 22), including analysis based on age and bone marrow dose. Cytogenetic preparations were obtained according to a protocol that includes cell culturing to the metaphase stage, hypotonic treatment, fixation of metaphase plates, and chromosome slide preparation. Telomeres were fluorescently stained using probes (DAKO, Denmark) in accordance with the manufacturer’s protocol. Standard methods of descriptive and comparative statistics were used.

Results. In exposed individuals, the median telomere length was statistically significantly higher than that in the comparison group (10.3% vs. 5.8%, p = 0.0001). Concurrently, this group exhibited a reduced frequency of ultra-short telomeres (1.6% vs. 5%) and an increased frequency of ultra-long telomeres (19.5% vs. 5%, p < 0.0001). A case-control study confirmed this pattern for the individuals with medium and high bone marrow doses. A statistically significant decrease in median telomere length was observed in donors with a high bone marrow dose compared to those with medium doses (11.9% vs. 10.6%, p = 0.0001). An increase in the bone marrow dose led to an exponential decrease in the frequency of ultra-short telomeres (R² = 0.23, p = 0.0036).

Conclusions. A decrease in relative telomere length was observed in non-exposed individuals with an increase in age. In the group of young donors aged 20–28 years, the median telomere length was 31.0%, comprising 13.0% and 5.8% (p = 0.0001) in the 60–67 and 71–83 age groups, respectively. The reference range for ultra-short telomeres in the 71–83 year group was 0–0.7%, being 25.6% and above for ultra-long telomeres. In exposed individuals, the median telomere length was statistically significantly higher than in the comparison group (p = 0.0001). Exposed individuals exhibited a reduced frequency of ultra-short telomeres and an increased frequency of ultra-long telomeres with respect to the comparison group (p = 0.004). A non-linear regression dependence of the frequency of ultra-short telomeres on bone marrow dose manifested in an exponential decrease in frequency with an increase in dose was noted.