Extreme Medicine

ISSN Print 2713-2757 ISSN Online 2713-2765

Extreme Medicine

SCIENTIFIC AND PRACTICAL REVIEWED JOURNAL OF FMBA OF RUSSIA

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Chikov AE, Kutsalo AL, Kiselev AD, Vladimirov VV, Krylova MV, Medvedev DS, Kaplun DI, Shpakovskaya II

Intense physical work is characterized by activity of physiological mechanisms as interrelated components joint for physical exertion. Definition of a set of individual and typological patterns of the physiological mechanisms’ activity answers the questions related to improvement of the athlete’s potential realization efficiency, definition of the limiting components and body’s reserve capacity, training load management. The study was aimed to assess the relationship between the responses of physiological mechanisms associated with standardized physical exertion and the pre-start state parameters. The athlete was through the step incremental test with the treadmill involving recording of the gas exchange parameters and heart rate to study physiological patterns. The physiological response parameters were calculated relative to the key phases of the exercise test: pre-start state, aerobic and anaerobic thresholds, peak exertion, fast and slow recovery phases. The mathematical model “Horseshoe of Rest” characterizing the athlete’s pre-start state before performing the test was constructed using the T-SNE dimensionality reduction algorithms. The model enables estimation of the release of non-metabolic СО2 throughout the testing period (MIC — 0.29) and the exertion period (MIC — 0.35).

Received: 2023-08-21

Published online: 2023-09-30

DOI: 10.47183/mes.2023.037

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VIEWS 687

Galkina AA, Bolyakina DK, Shatilova AV, Shatilov AA, Babikhina MO, Golomidova AK, Andreev SM, Shershakova NN, Khaitov MR

Skin and soft tissue infections following surgical procedures are usually caused by a broad range of bacteria and are the major cause of septic complications and hospital mortality. Treatment of such wounds is a challenge often resulting from the transition from acute to chronic inflammation due to persistence of pathogenic microflora in the wound tissue. The study was aimed to assess the wound-healing activity of the ointment composition based on the dispersion of fullerene C60 (AFD) in the in vivo model of skin wound, to estimate the effects of AFD on the expression of cytokines as markers of regenerative processes, to determine antibacterial activity of the developed cationic peptides. AFD was obtained by tangential ultrafiltration and used to make an ointment composition. The BALB/c mice were used to model the skin injury. The cationic peptides (CPs) were synthesized by the solid-phase method using the Fmoc technology. Antibacterial effects of CPs and AFD were estimated by colony counting. It was found that the AFD-based ointment exerted wound-healing and anti-inflammatory activity. The minimum bactericidal concentrations (MBC) of the CPs most active against the E. coli Dh5α strain, AB-1, AB-2, AB-3, and ST-10, were 1.15, 0.11, 0.74, and 0.74 mM, respectively, while MBC of ampicillin was 0.7 mM. We assume that constructing the hybrid compounds/fullerene C60 conjugates with active CPs will be a promising area of the development of drugs for treatment of wounds complicated by bacterial infection.

Received: 2023-07-28

Published online: 2023-09-29

DOI: 10.47183/mes.2023.036

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VIEWS 749

Misharin VM, Kochubey AV

Stagnation of the institution of assigning professional grades (categorization) draws increasing attention to the study of the opinions of physicians aimed at understanding and addressing the issues of this system. The study was aimed to get an estimate of the categorization system, the need for and directions of its transformation from physicians. The study involved an absentee poll of 64 physicians. Among then 48.4% had professional grades, 42.2% had scientific degrees, 51.6% were members of professional communities, 45.3% were engaged in teaching, 48.4% published scientific research results, 26.6% presented the results of their work during scientific and practical events. The average work experience as a physician was 13.8 ± 6.13 years. The questionnaire consisting of 21 statements with 5-point Likert scales was divided into four items: assessment of current categorization system; refusal of categorization; need to transform the system; directions of transformation. As a result, it was found that the respondents having professional grades, scientific degrees, who were members of professional communities engaged in teaching and scientific research, rated the existing categorization system lower (1.0 ≤ Ме ≤1.8 vs 2.6 ≤ Ме ≤ 3.0; 0.001 < р ≤ 0.034), they more often agreed that there was a need to transform the system (1.0 ≤ Ме ≤ 1.33 vs 2.7 ≤ Ме ≤ 3.0; 0.001 < р ≤ 0.013), than the respondents with no listed above traits. A total of 71.9% respondents agreed that there was a need for change, 1.6% agreed with the refusal of categorization. No correlation between work experience and the scores of items was revealed (0.144 ≤ р ≤ 0.627). Thus, despite the fact that the categorization system was rated low, the majority of physicians don’t want to abandon it seeing the need for transformation. The physicians’ beliefs are affected by the levels of their professional development.

Received: 2023-08-06

Published online: 2023-09-29

DOI: 10.47183/mes.2023.035

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VIEWS 661

Sedankin MK, Gudkov EA, Soloviev VYu, Mershin LYu

When eliminating the consequences of large-scale radiation accidents, primary triage of victims is of key importance during the early phase of medical evacuation. Information about lymphocyte counts (blood test) per unit of peripheral blood volume can be used for this purpose. The study was aimed to validate the method of using a lymphocyte test for prediction of acute radiation injury severity in the first days after the exposure associated with the radiation mass casualty incident, given peripheral blood was tested once. We performed correlation analysis of the data of laboratory studies focused on quantifying lymphocytes in peripheral blood of victims during the first days following the Chernobyl disaster and other radiation accidents on the territory of the countries of the former USSR (115 individuals), including radiation accidents with gamma neutron radiation (20 individuals). It was found that with the lymphocyte concentration of 0.2–1.0 × 109/L on day 2 after exposure, the absolute error of estimated dose was ±1.5 Gy in case of gamma exposure and ±1.3 Gy in case of exposure to gamma neutron radiation. When the lymphocyte concentration exceeds 1.0 × 109/L, mild acute radiation syndrome (ARS) is predicted, given the average dose is below 2.0 Gy; when the lymphocyte concentration is less than 0.2 × 109/L< the estimated average dose exceeds 4.0 Gy, which corresponds to severe or extremely severe ARS. Thanks to the lymphocyte test accessibility and simplicity, this biological dosimetry method can occupy a worthy position in the diagnosis of radiation injury associated with large-scale accidents, since the results of cytogenetic tests are not available within first days after the accident.

Received: 2023-08-10

Published online: 2023-09-28

DOI: 10.47183/mes.2023.034

Comments 0

VIEWS 705

Smolyakova EV, Sinitsyn EA, Zykov KA

In the treatment of patients with cardiorespiratory pathology, it is often necessary to simultaneously administer drugs that affect β-adrenergic receptors: β1-adrenoblockers and β2-agonists. β1-blockers can trigger a bronchospasm in patients with bronchoobstructive diseases, therefore, practitioners often decide not to prescribe them. This work aimed to evaluate functional parameters of patients with cardiovascular and bronchoobstructive diseases in the context of different sequences of administration of selective β1-blockers (bisoprolol) and long-acting β2-agonists (formoterol). This prospective, single-center 2-week pilot study involved 30 individuals suffering the aforementioned diseases. Using the envelopes method, we divided the patients into two groups of 15 people each. First group started therapy with a long-acting β2-agonist, second group — with a selective β1-adrenoblocker. While taking the β1-adrenoblocker, patients underwent a four-hour spirometric test enabling assessment of the external respiration function parameters. The tests and assessments have shown that the value of FEV1 went down in 33.3% of those who started therapy with a selective β1-adrenoblocker (bisoprolol 2.5 mg), and in the group that first took a long-acting β2-agonist for a week and then added bisoprolol 2.5 mg to the regimen the said value dropped in 7% of patients only. Thus, preceding long-acting β2-agonists, formoterol in particular, reduced the risk of bronchospastic incidents triggered by selective β1-adrenoblocker (bisoprolol) in patients with cardiorespiratory pathology.

Received: 2023-07-21

Published online: 2023-09-28

DOI: 10.47183/mes.2023.033

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VIEWS 730

Kodintseva EA, Akleyev AA

Disruptions of the Treg differentiation and functioning processes can play one of the crucial roles in the pathogenesis of radiation-induced malignant neoplasms in residents of the Techa riverside villages, who were chronically exposed in the low-to-medium dose range with predominant damage to the red bone marrow (RBM). This study aimed to determine the effect of radiation exposure, gender, age at the time of examination, and ethnicity on concentration of FOXP3 protein in lysates of mitogen-stimulated peripheral blood mononuclear cells in chronically exposed individuals in the period of cancer effects development. The main group consisted of 30 people aged 67–80 years, predominantly female and Turks. The comparison group included 10 unexposed individuals of similar age, gender, and ethnicity. In the main group, the mean dose to RBM was 867 mGr, to the thymus and peripheral lymphoid organs — 125 mGr. After 24-hour in vitro PHA stimulation, mononuclears were lysed, and the concentrations of the total protein and FOXP3 (using quantitative enzyme immunoassay) were measured. Among the different dose groups, there were no significant differences in FOXP3 concentration in mitogen-stimulated mononuclears (prior to the stimulation: 0 pg/ml in the comparison group and 3.50 ± 1.50 (0–27.19) pg/ml in the main group at p = 0.349; after the stimulation, respectively: 1.54 ± 1.51 (0–15.16) pg/ml and 9.71 ± 3.86 (0–77.92) pg/ml, p = 0.512). The variability of individual values is slightly higher in the main group than in the comparison group. Preliminary results allow concluding that the dose to RBM, thymus and peripheral lymphoid organs, age at the time of examination, gender, and ethnicity have no statistically significant effect on the concentration of FOXP3 protein in the lysates of the mitogen-stimulated peripheral blood mononuclear cells of chronically exposed people.

Received: 2023-07-31

Published online: 2023-09-28

DOI: 10.47183/mes.2023.032

Comments 0

VIEWS 655

Lednev EM, Makhnovskii PA, Vepkhvadze TF, Sultanov RI, Zhelankin AV, Kanygina AV, Popov DV, Generozov EV

Skeletal muscle plasticity is the ability to change morphofunctional properties in response to changes in contractile activity. Strength training increases the size of muscle fibers and maximum strength with the activation of protein synthesis. Regulation of these changes at the gene level has not been investigated properly. This study aimed to identify transcription factors associated with changes in the transcriptome of the human skeletal muscle in the context of single and regular strength exercises. We assessed changes in the transcriptomic profile of m. vastus lateralis of 10 young men (mean age 23 (20.8 - 25.9) years) before and after 12-week leg extensor muscles strength training course, as well as before, 8 and 24 hours after a single exercise. Transcriptomic profiling involved RNA sequencing, search for binding motifs and the associated transcription factors. Bioinformatic methods of statistics, FastQC, GraphPad Prizm 8, DAVID, R enabled analysis of the data acquired. The strength training course resulted in the enrichment of the functional groups of genes "secreted proteins", "extracellular matrix" and "basal membrane" (p < 0.05). Transcriptomic responses and the associated transcription factors differed 8 and 24 hours after a single session as well as after regular training sessions. Transcription factors involved in adjustment to regular and one-time loads participate in myogenesis, angiogenesis, regulation of fiber phenotype, proteostasis and other processes. Thus, regulation of gene expression during adjustment to the resistance training loads is a complex process that involves many transcription factors with different functions. Investigation of the role played by these factors in the context of adjustment to exercising is a potentially rewarding task.

Received: 2023-07-21

Published online: 2023-09-27

DOI: 10.47183/mes.2023.031

Comments 0

VIEWS 1096

Sharagin PA, Shishkina EA, Tolstykh EI

For residents of territories along the Techa River that was contaminated with radioactive substances in the 1950s, bone-seeking beta-emitting 89,90Sr were the main source of internal exposure of active (red ) bone marrow (AM). The dose of these radionuclides conditions the severity of leukemia risk for them. Improvement of the methods of internal AM dosimetry is an important task. Computational 3D phantoms of the skeleton sites are a component of the solution for this task. Simulation of radiation transfer in a heterogeneous bone model allows estimating the dose conversion factors from radionuclide activity to AM dose. This manuscript continues the series of papers covering the development of a set of computational phantoms of a reference human being of different age. The objective of the study was to develop a computational phantom of a one-year-old child skeleton for internal AM dosimetry (exposure due to incorporated beta emitters). Using the original SPSD (stochastic parametric skeletal dosimetry) model, we develop voxel 3D models of skeletal sites. Skeleton sites with active hematopoiesis were modeled as a set of phantoms of simple geometries. Distribution of AM throughout the skeleton and parameters of the phantoms were assessed on the basis of the published results of measurement done in real bones of children aged 9 months to 2 years. The generated computational phantom of a one-year-old child consisted of 39 segments. It simulates the structure of the bone tissue, location of AM, and population variability of the skeleton microstructure and size parameters.

Received: 2023-06-14

Published online: 2023-09-26

DOI: 10.47183/mes.2023.030

Comments 0

VIEWS 826