Vol 26, No 4 (2024)

This article analyzes the scope of services provided by a dentist within the military medical service of the Armed Forces of the Russian Federation during a modern armed conflict. The study included two stages: a prospective stage involving patient care (preventive oral cavity examinations in citizens mobilized for military service) and a retrospective analysis of dental care provided by the military medical service during a military operation (data from preventive examinations, oral sanitation plans for armed forces personnel, and reports from senior dentists of military districts). It has been established that the need for oral sanitation among career military personnel averages 72% and reaches up to 81% among volunteers and citizens mobilized for military service, increasing the workload for both military and hospital dentists. On average, 85.4% of armed forces personnel require outpatient dental care, with each individual having an average of 5.6 teeth requiring treatment: 3.8 for caries, 0.8 needing endodontic treatment, 1 tooth requiring extraction, and 7.4 teeth needing restoration among those requiring prosthetics. It was noted that the critical factors were the nature of combat operations, the workload of medical evacuation stages, and the availability of various resources in the regimental aid station or the medical company of a brigade. These factors often hinder the full deployment of dental equipment and the ability to provide treatment for oral disorders, both on an elective and emergency basis. Satisfactory conditions for this type of medical care are achievable only in a dental office within a separate medical battalion or a special task medical detachment. To improve the provision of dental care to armed forces personnel by the military medical service of the Armed Forces of the Russian Federation during a military operation, the authors propose the following. Dental offices should be equipped with portable turbine dental units, which have proven to be highly effective in real combat conditions, and with portable dental X-ray machines to significantly improve the quality of diagnostics and treatment of dental disorders. In addition, given the challenges of restocking medical consumables, dentists should ensure their timely requisition and monitoring their receipt, since only 36.6% of medical units are equipped with standard dental consumables, necessitating urgent measures to establish a stable supply system.

This study evaluates the effect of the hemostatic surgical preparation, containing a 1% aqueous solution of partial silver salt of polyacrylic acid with silver nanoparticles, on the morphological features, viability, and energy status of Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Atomic force microscopy and bioluminescent determination of bacterial adenosine triphosphate were used to assess the morphological and functional reactions of bacterial cells. Exposure to the preparation was found to cause diverse reactions in different bacteria. Gram-positive cocci increased their volume, decreasing their relative surface area, thereby reducing their contact with the preparation. These changes can be considered one of the adaptive mechanisms of staphylococci to the toxic compound. Gram-negative bacteria (P. aeruginosa and E. coli) also changed their sizes in response to hemostatic preparation, but both exhibited an increase in relative surface area and cell surface roughness, which may indicate depletion of their adaptive potential.

Bacterial survival and intracellular adenosine triphosphate levels in cells exposed to hemostatic preparation showed that most staphylococci became non-viable, while the effect of the preparation was concentration-dependent. Exposure of Pseudomonas to the undiluted preparation resulted in their death, while a similar effect was observed for E. coli at a 10% concentration. The assessment of the viability and energy status of the studied strains confirmed the hypothesis of greater tolerance of staphylococci to hemostatic preparation, as they remained viable even after exposure to the undiluted preparation. The addition of the hemostatic preparation to a Pseudomonas suspension led to their death, whereas a similar effect was observed for E. coli even with the diluted preparation. Overall, the morphological changes in the bacterial cell wall and a decrease in their adenosine triphosphate content after exposure to the preparation demonstrate its antibacterial effect against certain types of clinically significant microorganisms.

The study evaluates the dynamics of aquaporin (aquaporin-1, aquaporin-5, and epithelial sodium channel) content in the aero-hematic barrier during the latent phase of rat intoxication with carbonyl chloride (phosgene), thermal decomposition products of fluoroplast containing perfluoroisobutylene, and nitrogen dioxide. Rat intoxication was modeled using average lethal concentrations of these toxic substances. At 30 and 60 minutes post-exposure, pulmonary coefficient was measured and histological and immunohistochemical studies were performed. Western blot analysis was used to determine the aquaporin-5 content in rat lung tissues exposed to the thermal decomposition products of fluoroplast. It was found that rat intoxication with phosgene and thermal decomposition products of fluoroplast containing perfluoroisobutylene led to an increase in the relative content of aquaporin-5 and epithelial sodium channel-positive cells in lung tissues as early as 30 minutes post-exposure. At 60 minutes post-exposure, there were signs of the interstitial phase of toxic pulmonary edema and an increase in the pulmonary coefficient. Exposure to nitrogen dioxide resulted in an increase in the pulmonary coefficient and the relative content of aquaporin-5-positive cells, as well as pronounced signs of the interstitial phase of edema 30 minutes post-exposure. Western blot analysis using anti-aquaporin-5 antibodies revealed an increase in the staining intensity of complexes with molecular weights of 25 and 50 kDa, suggesting the formation of aquaporin-5 tetramers and their likely translocation from the intracellular compartment to the plasma membrane of alveolar cells. These findings indicate that aquaporin-5 plays an important role in the pathogenesis of toxic pulmonary edema induced by the studied pneumotoxicants. Targeting these molecules may be a promising approach for pathogenetic therapy of poisoning.

The feasibility of removing damaging fragments from the spine in gunshot and mine-blast injuries is assessed based on the data of their composition and cytotoxicity. Four damaging fragments removed from the spine and paravertebral tissues were analyzed. Elemental analysis was performed using a scanning electron microscope. The composition of the damaging fragments was studied using spectral analysis. The cytotoxicity of the medium with damaging fragments was evaluated using the methyl tetrazolium test, comparing to the control medium. Morphological changes in cells were assessed using optical light microscopy, comparing to the control. Elemental analysis showed that all studied fragments consisted of alloys of various metals and other chemical elements. During the first few weeks of incubation in a complete nutrient medium, metals underwent fairly active oxidation, producing an orange precipitate. During further incubation, the oxidation of metals continued quite intensively, leading to a change in the nutrient medium and reducing cell proliferation. Moreover, morphological examination showed that cells exposed to metal oxides were rounded, while control sample cells were elongated and spindle-shaped. The methyl tetrazolium test revealed high cytotoxicity of all the fragments studied. All fragments were found to release toxic metal oxides into the nutrient medium, significantly reducing cell viability, regardless of their elemental composition. To prevent complications associated with possible local and/or systemic toxicity of metal fragments, as well as early and late infections, it is recommended to remove projectiles to the maximum extent feasible.

This study evaluates the significance of blood microRNA (miR-21-5p) levels as a biomarker for the development or progression of cardiovascular diseases after COVID-19. The levels of circulating miR-21-5p in the blood were analyzed in 120 patients with cardiovascular diseases recovering from COVID-19. Based on inclusion and exclusion criteria, six groups of patients were formed with 20 patients in each of them. All patients had previously suffered from COVID-19 required hospital care. The groups were divided by the presence of previously verified coronary heart disease, hypertension, and atherosclerosis, as well as the absence of diagnosed cardiovascular diseases. The patients were also divided into those with worsening of preexisting circulatory system diseases or their onset and those without such diseases. All patients underwent circulatory system examination before and after COVID-19. Statistically significant differences in miR-21-5p levels were revealed when comparing groups with previously verified coronary heart disease with and without worsening, as well as groups without preexisting cardiovascular diseases. No statistically significant differences in cardiovascular diseases progression were identified when comparing patients with previously verified hypertension or atherosclerosis. Therefore, blood miR-21-5p appears to be a promising biomarker for assessing the progression of coronary heart disease, including in patients recovering from COVID-19. This method correlates with clinical observations in patients with coronary heart disease, as well as diagnostic investigation data. Further studies on larger cohorts of patients with cardiovascular diseases and follow-up monitoring of miR-21-5p expression levels may increase the informative value of this biomarker. It could aid in clinical decision-making process and follow-up monitoring of patients with such diseases in order to reduce adverse complications.

The study evaluated key spirometric parameters in patients with post-tuberculosis (post-TB) lung sequelae after recovery from a new coronavirus infection. The main group incliuded 14 patients with clinically cured respiratory tuberculosis who had recovered from the new coronavirus infection and, after recovery, were sent to the Glukhovskaya tuberculosis sanatorium for treatment in 2020-2021. The control group included 52 patients with residual post-TB sequelae, who did not have a new coronavirus infection and who were treated at the sanatorium during the same period. The groups were comparable in terms of epidemiological and clinical criteria, except for post-TB sequelae: the main group included 13 cases (92.9%) of minor post-TB sequelae, 1 case (7.1%) of major post-TB sequelae, and the control group included 36 (69.2%) and 16 (30.8%) cases, respectively. Pulmonary function tests included vital capacity, forced vital capacity, forced expiratory volume in 1 second, and forced expiratory volume in 1 second/forced vital capacity. Tests were performed at admission to the sanatorium and after 1 month. At stage 1 in the main group, vital capacity, forced vital capacity and forced expiratory volume in 1 second were on average below the predicted level (>80%) compared with the control group, and after sanatorium treatment the same parameters improved slightly. In the control group, the initial indicators were significantly higher, the rates of recovery of vital capacity of the lungs and forced vital capacity of the lungs were comparable with the main group, during the 2nd examination, the average levels of recovery of vital capacity of the lungs and forced vital capacity of the lungs approached, and in terms of forced expiratory volume in the 1st second, they reached the norm. At baseline, low ventilatory lung capacity correlated with clinical symptoms, as 42.8% of patients in the main group and 55.7% of controls reported shortness of breath. However, after sanatorium treatment, the control group more often showed parameters below 60%: 7.7% of cases for vital capacity, 17.3% for forced vital capacity, 11.5% for forced expiratory volume in 1 second, while the main group showed mostly slight or moderate decrease of these parameters. Therefore, the new coronavirus infection has a negative impact on the functional capacity of the respiratory system, but major post-TB sequelae also contribute to the development of ventilatory disorders.

The study compared marking of small-diameter peripheral lung neoplasms by preoperative transthoracic use of 1% aqueous methylene blue solution and placement of an anchor marker system. The study evaluated the results of treatment of 36 patients with pulmonary nodules, including 27 men and 9 women aged 52 to 76 years, who were examined and treated at the Surgical Clinic of the S.M. Kirov Military Medical Academy in 2020-2023. Marking of small-diameter peripheral lung neoplasms by transthoracic use of 1% aqueous methylene blue solution made possible to detect abnormalities and lesions and perform a biopsy in 73.3% of cases. The duration of the diagnostic procedures was 30 [20-40] minutes. No postoperative complications were reported. The mean length of stay in this group of patients was 8 [6; 12] patient days. Placement of an anchor marker system allowed detection and verification of lung lesions in 95% of cases. In addition, the duration of videothoracoscopic biopsies was also 30 [20-40] minutes. No complications or deaths were reported. The mean length of stay was 7 [5; 11] patient days. The use of anchor markers to label small peripheral pulmonary nodules in the preoperative phase has some significant advantages compared with dye injection techniques, such as shorter duration of lesion mapping (p = 0.046) and less manipulation complications (p = 0.04), as well as a higher frequency of lesion detection during minimally invasive procedures. When comparing various techniques for marking pulmonary lesions, it was found that mapping of small-diameter peripheral pulmonary infiltrates using anchor markers is characterized by high performance, greater safety, facilitates intraoperative navigation for biopsy of small-diameter peripheral pulmonary neoplasms, and is superior than transthoracic use of 1% aqueous methylene blue in terms of rates of detection of pulmonary nodules during minimally invasive procedures, duration of manipulation, and complication rates.

Gunshot and landmine wounds to the upper and lower extremities are the most common injuries in modern armed conflict. In previous armed conflicts, reconstructive surgery of peripheral nerves was not performed until 3-6 months after injury because dysfunction was often associated with a contusion mechanism of injury and recovery of nerve function may occur without surgical treatment. A new approach to care for patients with peripheral nerve injuries was developed and implemented by the authors. In recent years, the Military Medical Academy has widely used neuroimaging diagnostic techniques, such as magnetic resonance neurography and ultrasound examination of peripheral nerves. They can confirm or rule out a complete anatomical rupture of the nerve trunk. In the presence of characteristic pathomorphologic changes, peripheral nerve reconstructive surgery is performed as early as possible after injury (1.0–1.5 months). The earlier the nerve is reconstructed, the faster and more complete the functional recovery. Care of patients with peripheral nerve injury requires a comprehensive approach and close collaboration between neurosurgeons and related specialists. Such an approach allows identifying peripheral nervous system injuries in incoming surgical patients. This approach has proven effective in the treatment of neuropathic pain in this population. Early reconstructive intervention increases the effectiveness and decreases the time to regain lost limb function, thus shortening the rehabilitation period and improving quality of life.

The paper evaluates Russian and foreign literature on the positive effects of dosed hypoxia on human body in the setting of training stimulation. This model can serve as a theoretical basis for the development of a hypoxic preconditioning technique, which can be extremely useful for air medical officers to maintain the professional health of pilots in modern conditions. The aim of this review was to inform a wide range of stakeholders about the various effects of hypoxic preconditioning, including cardioprotective, neuroprotective and vasoprotective effects. Existing hypoxic training techniques were reviewed, especially the advantages of normobaric hypoxic training to improve the functional status of pilots. The main advantages of this technique include possibility of wide use on flat terrain, the absence of changes in atmospheric pressure during training, no need for specially trained personnel and special premises, the possibility of selecting an individual training program, combination of hypoxic training with everyday tasks, minimal side effects, and long-term maintenance of training results. The mechanisms underlying hypoxic preconditioning are discussed, including the activation of genes encoding proteins involved in the regulation of oxygen homeostasis. The latest research data in hypoxic training are described. The paper also addresses issues that are not generally understood by practitioners who use hypoxia for therapeutic and preventive purposes (effectiveness of different techniques, role of blood saturation levels during hypoxic training, difference between preconditioning and postconditioning, and other aspects of practical hypoxic therapy). All these questions need to be answered in the near future in order to better understand the activation of human internal defense mechanisms by non-drug methods. Further studies are needed to determine the optimal preconditioning technique, including the duration and intensity of hypoxia exposure.