Vol 25, No 1 (2023)

This study presents the technology of developing a universal stent graft for endovascular treatment of aneurysms and aortic dissection of various localizations, without considering the vessel diameter. A self-expanding nitinol stent was used as the frame of the main trunk of the stent graft. During the study, several variants of the aortic linear graft were manufactured and tested. The optimal stiffness and diameter of the nitinol wire were selected based on the results. When creating a bifurcation module, special attention was paid to simplifying the positioning and “intravascular assembly” of the structure. Implantable modules have been developed for the prosthetics of the main branches of the aorta. Dacron, optimal in terms of fiber structure, was chosen as the material of the woven shell of the graft. Linear extensibility, compactness of the pile, and tensile strength during fenestration were evaluated. To determine the heparin-controlled surgical porosity, experimental samples of stent grafts were tested on a stand simulating arterial blood flow. The wall material of the developed device had a heparin-controlled surgical porosity of 50–150 mL/min/cm² at 120 mm Hg with the possibility of maintaining a controlled endolic. The graft wall created a pressure gradient of no more than 3 mm Hg, and the flow velocity indicators were quite sufficient for adequate perfusion of vital organs. After the inactivation of heparin, blood permeability became zero. The implantation technique of the developed product was implemented on a silicone aortic phantom simulating aneurysm expansion with and without dissection. The phantom contour was filled with a solution simulating the rheological properties of native blood. Pulsating blood flow was simulated using a perfusion pump. Under X-ray control, a stent graft was installed on five large biological samples (sheep). Implantation was performed in the aortic arch with prosthetics of the brachiocephalic trunk and the suprarenal aorta with prosthetics of the visceral branches. With the experiment, we hope that the result will allow us to minimally invasively help patients suffering from aneurysms of any localization.

Acute toxic hepatitis is a serious health problem for the working population. The currently widely used pharmacological preparations with claimed hepatoprotective properties for the treatment of liver diseases have dubious therapeutic efficacy and cannot restore functional and structural changes in the damaged organ. Thus, the search for new methods of treating liver diseases, including toxic etiology, is an urgent task. An experimental study was conducted on 134 nonlinear white outbred rats (3–5 months) weighing 250–390 g. The animals were divided into four groups: group I, control group (n = 15); group II, single intragastric administration of an oil solution of carbon tetrachloride at a dose of 1500 mg/kg (n = 41); group III, single intravenous administration of multipotent mesenchymal stem cells of the mouse (n = 20); group IV, single intragastric administration of an oil solution of carbon tetrachloride at a dose of 1500 mg/kg and subsequent intravenous transplantation of multipotent mesenchymal stem cells of the mouse (2 × 10⁶) (n = 58). On days 1, 3, 5, and 7 of the experiment, blood sampling was performed for biochemical analysis, and organs and tissues were selected for histological and morphometric studies. The transplantation of multipotent mouse mesenchymal stem cells reduced the mortality of animals after exposure to carbon tetrachloride and did not cause acute toxicity. According to a morphometric study, starting from day 3, the introduction of multipotent mouse mesenchymal stem cells led to a statistically significant decrease in the infiltrative processes in the liver tissue. Statistically significant changes in the biochemical composition of the rat blood serum were noted against the transplantation of multipotent mouse mesenchymal stem cells: a decrease in the activities of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, gamma-glutamyltransferase, amylase, creatinine, uric acid, direct and total bilirubin, and cholesterol. The transplantation of multipotent mouse mesenchymal stem cells was found to be an effective method of treating acute toxic hepatitis. The use of multipotent mouse mesenchymal stem cells contributed to an increase in the survival rate of laboratory animals and faster recovery of structural and functional disorders in liver tissue after its acute toxic damage.

This study analyzed the tolerability of factors of flight work by Vietnamese pilots. The effects of aerobatic overloads (statoergometry), hypoxia (hypoxic test), and statokinetic loads (Otolith reaction-10 test) were simulated. To assess the functional state, computer stabilography and psychophysiological techniques were used to determine the reaction of choice and the critical frequency of light flashes. Height, bodyweight, blood pressure, heart rate, and blood oxygen saturation were recorded. In this study, 17 Vietnamese (group 1) and 24 Russian (group 2) pilots aged 19–22 years were examined. Significant differences in height and bodyweight were found between the groups, which affected the tolerance of static muscle loads. Only 12% of the Vietnamese pilots completed the statoergometric test, and only one of the Russian ones did not reach the fifth stage. The conducted tests did not significantly affect the psychophysiological indicators, although they had multidirectional changes. Thus, when performing a normobaric hypoxic test, the blood pressure, heart rate, and blood oxygen saturation at the 5^th minute of the recovery period returned to their original values. A slight increase in the pulse rate did not reach statistical significance. In general, the tolerance for normobaric hypoxia in both groups was good. However, a significantly smaller area of displacement of the pressure center of the statokinesiogram indicated a greater strain of adaptation mechanisms in group 1 than in group 2. The reaction to the statokinetic effect also indicated a satisfactory tolerance of the vestibular test “Otolith reaction-10”. Moreover, the tension of adaptive mechanisms in group 1, in contrast to group 2, was more pronounced. In addition, changes in the indicators of computer stabilography suggest a greater strain of adaptive mechanisms in Vietnamese pilots than in Russian pilots. The results indicate the need to develop methods of preparation for flights with aerobatic overloads and a system of psychophysiological training of pilots of the Socialist Republic of Vietnam to increase resistance to the influence of professional factors of flight work and the successful operation of Russian aviation equipment.

The possibilities of improving controlled transosseous osteosynthesis in anatomical experiment by changing the design of the external fixation apparatus by individualizing the design of the apparatus, ensuring accurate dynamic reposition of bone fragments, and establishing more effective X-ray control using X-ray transparent elements of the external fixation apparatus design are considered. The study was performed under wet preparations of an isolated femur of ten rabbits with a bone diaphysis fracture created. The original compression–distraction apparatus of external fixation developed was experimentally approved. In all experiments, an accurate comparison of bone fragments was obtained by dynamic reposition owing to the use of autonomous hinge modules and the presence of an individualized base module located in the pathological focus of the bone structure. The study showed the need to individualize the size of the design of the elements of the device. This is because the damaged limb does not have the correct cylindrical shape, unlike the shape of the apparatus. Changing the morphometric parameters of the damaged limb segment during osteosynthesis requires a specific individual geometry of the base module. The individualization of the shape and size of the base module should provide for the possibility of implementing the stages of moving fragments of bone structures, individual in each case. The dimensions of the X-ray transparent plastic ring or the shape of the hinge module close to the ring should correspond to the geometric dimensions of the limb segment at the fracture site and subsequently when correcting the position of bone fragments in each individual case. The most often optimal is the distance from the supports of the device to the surface of the limb segment of 5 cm, which determines the geometric dimensions of the individualized base module. In general, the directions of further improvement of the hardware of the technique of controlled transosseous osteosynthesis are determined. The effectiveness of X-ray control owing to the use of X-ray transparent structural elements of the device is shown. It has been revealed that in the conditions of anatomical experiment, controlled transosseous osteosynthesis may be more effective by improving the hardware owing to the individualization of the structural elements of the apparatus in combination with the use of autonomous hinge modules.

The medical documentation (n = 146912) introduced into the system “Regional fragment of the unified state information system in the field of healthcare” of Saint Petersburg for 2019–2021 was analyzed. To evaluate the mortality of patients due to heart failure, all deceased patients from 2019 to 2021 in Saint Petersburg (n = 192133) were taken as a basis, and based on a thorough study of medical documentation, patients who died from cardiovascular diseases and because of heart failure were singled out separately. The total mortality from all causes in Saint Petersburg in 2019 was 53025 people; in 2020, 66468 people; and in 2021, 72640 people. The analysis of mortality due to cardiovascular diseases from 2019 to 2021 showed an upward trend of 20.1% over the 3-year period of data analysis. When analyzing the prevalence of heart failure among deceased patients, an increase of 129.4% was noted over this period. The obtained results of the prevalence, mortality, and mortality of patients due to heart failure on the example of a megalopolis are the most relevant at the current time; they indicate a steady increase in the number of patients suffering from heart failure with an increase in the burden on the city’s healthcare system. Simultaneously, there is insufficient continuity in the provision of medical care to patients suffering from heart failure, which is because of not only a shortage of medical personnel at all stages of medical care but also insufficient compliance of patients who either do not want to be treated or cannot continue treatment. Moreover, a significant disconnect was found in the continuity of medical care at the stages of pre-hospital and hospital treatment, as well as further outpatient follow-up of patients suffering from heart failure in the metropolis. All this leads to a significant increase in the mortality and mortality of patients suffering from heart failure, despite all the existing modern effective drug therapies. It appears critical to create a unified register platform for recording patients with heart failure, which will allow for a more accurate understanding of epidemiological aspects, the solution of which will improve the quality of medical care, identify the need for the crucial medicines, and reduce mortality, and mortality rates due to heart failure.

This study analyzed and demonstrated the role of inflammatory mechanisms and inflammation markers in the development of atrial fibrillation, their significance in the structural and electrical remodeling of the atria, and pharmacological agents that can be effective in reducing inflammation. Data were obtained from the analysis of retrospective and prospective studies and systematic reviews. The available domestic and foreign scientific studies indexed in PubMed, Google Scholar, and eLibrary.ru were analyzed. Atrial fibrillation is one of the most common arrhythmias in adults and is associated with many complications and mortality. The pathophysiological mechanisms of this arrhythmia remain completely unclear, and their search continues at the molecular level. Atrial fibrillation causes electrical and structural changes in the myocardium, which lead to further pathological transformations of the heart, and some of them are associated with inflammation, which has been demonstrated in studies on an experimental model and heart tissues of patients with this rhythm disorder. Whether inflammation is the cause of the development of this arrhythmia or its consequence is not clearly understood. Statins, corticosteroids, colchicine, genetically engineered biological drugs, which have a specific application point in the inflammatory cascade, and some other drugs, such as anticoagulants, polyunsaturated fatty acids, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and mineralocorticoid receptor antagonists, also take place in the treatment of atrial fibrillation. However, their applications are not clearly specified. Currently, research continuously aims at finding effective ways to prevent and treat this nosology. Thus, promising ways to reduce the role of inflammation in the occurrence, recurrence, diagnosis, and treatment of atrial fibrillation are relevant in the development of precision medicine.

The data of modern scientific literature characterizing individual mechanisms of transformation of normal cells and various stages of oncogenesis associated with viruses were analyzed. The data of sequencing of tumor genomes and amino acid sequences indicate that most tumors are a consequence of the accumulation of sequential mutations, a significant contribution to the formation of which was made by oncogenic viruses. Processes that alter or impair the functioning of signaling pathways can contribute to transformation and oncogenesis. The phosphorylation of the ribosomal protein S6 by protein kinase B, which increases the speed, and prolongs the translation time, is critical in oncogenesis. Protein kinase B inhibits the processes of apoptosis, participates in the regulation of the cell cycle, and regulates tissue growth; an increased level of this protein is found in various tumors. Transformation and tumor-associated processes are the result of a combination of dominant mutations with increased function of proto-oncogenes and recessive mutations with a loss of function of tumor suppressor genes encoding proteins that block cell cycle progression. The function of any gene product can be altered by oncogenic viruses. Transforming proteins alter cell proliferation with a limited set of molecular mechanisms. The integration of proviral deoxyribonucleic acid in a specific region of the cellular genome contributes to the induction of tumor-associated processes by non-transductive viruses. Cellular oncogenes induce signaling at various stages of the cell cycle, which ultimately leads to its dysregulation and progression. In cell transformation, the interaction of E1A viral proteins with tumor suppressors RB, histone acetyltransferase p300/CVR, and inhibitors of cyclin-dependent kinases p27 and p21 is crucial. Virus-transforming proteins have various properties, from changing the sequences of primary amino acids to inducing various variants of biochemical activity. Most tumors induced by non-transductive retroviruses result from increased transcription of cellular genes (myc) located in close proximity to integrated proviruses. Latent membrane protein 1 is an integral protein of the plasma membrane and functions as a constitutively active receptor and facilitates the transition from a latent course of infection to a lytic one. In the absence of a ligand, this protein oligomerizes, and activates proteins that control cell proliferation and survival.

The gut microbiota plays a fundamental role in maintaining normal organism homeostasis, regulating a wide range of metabolic, biosynthetic, and immune functions. This complex ecosystem, together with cellular, and stromal components of the intestinal wall, forms the intestinal microbial-tissue complex, which pathology is considered a universal mechanism for the development of many diseases, including chronic kidney disease. Accumulation of nitrogen metabolism products in the intestine, specific diet, polypharmacy, sedentary lifestyle, limited fluid intake, and violation of gastrointestinal motility in patients with chronic kidney disease lead to a decrease in the number of bacteria synthesizing short-chain fatty acids with crucial physiological effects, along with an increase in the content of anaerobic proteolytic bacteria expressing uricase, urease, and p-cresol-, and indole-forming enzymes. The features of gut dysbiosis depend on the etiology of chronic kidney disease and severity of renal insufficiency and differ significantly in individuals receiving various renal replacement therapies (hemodialysis, peritoneal dialysis, kidney transplant recipients). Abnormal microbial metabolism enhances the production and accumulation of microbial-derived uremic toxins: p-cresyl sulfate, indoxyl sulfate, and trimethylamine-N-oxide. Renal insufficiency, through mechanisms mainly associated with the hydrolysis of accumulated in the lumen of the intestine urea, leads to inflammation, and swelling of the intestinal wall, which is accompanied by disorders of the immune tolerance of the mucous layer and disorganization of intercellular junctional complexes, which are critical modulators of intestinal intercellular transepithelial transport. Uremia-induced impairment of the gut epithelial barrier integrity induces the systemic translocation of numerous immunogenic substances generated by the aberrant microbiota, followed by the development of oxidative stress and chronic subclinical inflammation that causes the progression of chronic kidney disease and related complications. The most pronounced changes were observed in people with end-stage chronic kidney disease. Further study of the bidirectional relationship between the kidneys and intestinal microbial-tissue complex will contribute to the development of new directions of pathogenetic therapy and prevention of adverse outcomes in patients with chronic kidney disease.

The role of Admiral Cornelius Kruys (1655–1727), one of the closest, and loyal associates of Peter the Great, who stood at the foundation of the regular Russian navy, was considered. Kruys was recruited into the Russian duty by Peter I in 1698 with the rank of Vice Admiral and devoted his entire life to serve in Russia and the Russian fleet. Having extensive professional experience and knowledge of maritime affairs, Kruys played a special role in organizing, building, and arming the Baltic fleet according to the European model. Taking over access to the sea, Russia became one of the greatest maritime powers of Europe.

The article is based on a large amount of documentary material from the funds of the Russian State Naval Archive (Saint Petersburg). All the reforms of Peter I were focused on the formation and development of Russia along the European path, which include implementation of the advanced achievements of Europe in the field of military and naval affairs, science, technology, construction, culture, and medicine. The main time of the reign of Peter I falls in the period of the Great Northern War between Russia and Sweden (1700–1721). The Sovereign always paid special attention to the organization of the regular army and navyand recruiting the best military specialists from the leading European countries for this purpose. In the seventeenth and eighteenth centuries in European countries, the military medical service, hospitals, and infirmaries were an integral part of the army and navy. Such an organization of the armed forces of Russia was necessary for Peter I. On October 30, 1704, Vice Admiral Kruys presented the project of organization and construction of the Baltic fleet to Peter I. The project contained “A list of needs for His Royal Majesty’s ship fleet: in the sovereignty of the government of Ingermonland, which should be hastily prepared to fill stores.” Along with a list of the necessary marine specialists, materials, and equipment for the construction and equipment for ships, Kruys emphasized the need for the simultaneous establishment of a Naval Hospital or a clinic for at least 500–600 patients for the personnel of the Ingrian Navy (“zelo potrebno yest”). This critical project was approved by the Sovereign and was soon put into production. The birth of the Naval (Admiralty) Hospital of Saint Petersburg took place simultaneously with the Baltic fleet. Since then, the Naval Hospital has become an integral part of the Russian Navy. On November 5, 1704, the Admiralty fortress-shipyard was laid in Saint Petersburg, and soon the construction of the Baltic fleet under the control and leadership of Kruys was launched.