Kazan medical journal

Aim. To study the mechanisms of venous return and the functioning features of lower extremity venous valves in horizontal and vertical positions.

Methods. The study, conducted from April 2019 to December 2020, included 100 people. The study participants were divided into 2 groups. The first group was represented by 44 patients (88 limbs) with varicose veins, whose venous system was examined by duplex ultrasound scanning during inpatient rehabilitation. The second (control) group consisted of 56 healthy individuals (92 limbs) without visible signs of venous pathology who underwent an outpatient examination of the venous system. The average age of the patients in the two groups was 49.2±2.4 and 51.1±1 years, respectively; women predominated in both groups. The qualitative and quantitative parameters of venous blood flow were studied in the study. Venous valvular insufficiency was assessed by using reflux duration and the Psatakis index. A morphometric study was conducted on 140 limbs of 48 human corpses, from which venous fragments were taken for biomechanical studies of the valves. The clinical characteristics of patients are presented by descriptive statistics, quantitative parameters are reported as the mean value (M) and standard deviation (SD). The differences were tested for significance by using the Student's t-test.

Results. In the study, we introduced the concept of the valve index, the aspect ratio of the ellipse, the shape of which has a venous valve in cross-section. Duplex ultrasound scanning, as well as a morphofunctional examination of the valves, made it possible to establish that the valve index is significantly higher in the presence of signs of varicose veins, which indicates dilation and incipient varicose vein, which leads to valvular insufficiency. The elasticity index defined by us, as the indicator of change in the venous lumen size, measured by the ratio of its diameters, also significantly (p=0.034) differed in the studied groups: the elasticity index in the group of healthy people was 1.37±0.11, in the group of patients with varicose veins — 1.56±0.17. The studied factors allowed us to develop a test that has an important prognostic value for the early diagnosis of varicose veins as well as the implementation of preventive health measures.

Conclusion. The features of venous blood circulation and valve function studied in the study not only have prognostic value for the early diagnosis of varicose veins but are also of practical interest for developing methods of surgical correction of venous valvular insufficiency.

Aim. To compare the effectiveness of the angiotensin-converting enzyme inhibitor enalapril and the angiotensin II receptor antagonist valsartan in patients with heart failure with mid-range ejection fraction (HFmrEF) from the standpoint of the effect on the clinical picture, echocardiographic parameters and the level of the N-terminal fragment of the prohormone brain-type sodium (NT-proBNP).

Methods. 110 patients with heart failure with mid-range ejection fraction were included in the study based on the City Clinical Hospital named after N.I. Pirogov of Orenburg between 2018 and 2020. All patients were divided into two randomized groups. Patients of the first group (n=55) were prescribed enalapril, the second group (n=55) — valsartan. Each patient was followed up for 1 year. The six-minute walk test, NT-pro-brain natriuretic peptide level, echocardiography parameters were assessed in dynamics. Statistical analysis was performed by using Statistica 10.0 software, Shapiro–Wilk, Mann–Whitney, Wilcoxon tests.

Results. During the year of observation in both groups, there was a significant decrease in the functional class of chronic heart failure (p <0.005) without a statistical difference between the groups (p=0.251). The distance during the six-minute walk test increased from 350 (310–400) m to 490 (420–530) m (p <0.001) in the first group, from 360 (330–400) m to 510 (450–520) m (p <0.001) in the second group, also without significant differences (p=0.361). The NT-pro-brain natriuretic peptide level decreased from 491 (410–610) pg/ml to 286 (187–350) pg/ml (p <0.001) in the first group, and from 446 (376–534) pg/ml to 210 (143–343) pg/ml (p <0.001) in the second, with a more significant change in the second group (p=0.020). The dynamics of echocardiography parameters were comparable in the groups (p >0.05), while ejection fraction normalized in 89.1% of patients received enalapril and 92.7% of patients received valsartan.

Conclusion. The efficacy of enalapril and valsartan in heart failure with mid-range ejection fraction is comparable in its effect on the clinical picture and echocardiography parameters with a more pronounced decrease in NT-pro-brain natriuretic peptide when taking valsartan during a year of follow up.

Aim. To assess the clinical and immunological features in patients with chronic opisthorchiasis, depending on the duration of the infection.

Methods. The first group consisted of 19 patients with the duration of the infection up to 1 year, the second group consisted of 21 patients with the duration of the infection between 1 and 5 years, the third group was formed of 23 patients with the duration of the disease more than 5 years, the control group — 20 healthy individuals. Immunological research was carried out at the Clinical Diagnostic Center. Statistical processing was performed using Microsoft Excel 2010 and Statistica 6.0 software. The statistical significance of differences was determined by using the Mann–Whitney test (U-test) at the level of significance of p <0.05. The correlations were assessed by calculating Spearman's rank correlation coefficients.Results Clinical features of chronic opisthorchiasis were revealed in the disease duration groups of up to 1 year, from 1 year to 5 years, more than 5 years: the subclinical course was most common in the group of up to 1 year; cholangiohepatitis prevailed in the group of between 1 to 5 years, allergic skin syndrome, cholangiocholecystitis and pancreatitis dominated in the group of more than 5 years. The immune response in chronic opisthorchiasis was characterized by: up to 1 year — lymphocytosis, increased levels of immunoglobulins M (IgM) and circulating immune complexes (CIC), a decrease in the number of T-lymphocytes (CD3+), as well as an increase in bactericidal activity of leukocytes (BAL); between 1 and 5 years — monocytosis, increased levels of immunoglobulins M, immunoglobulins G and circulating immune complexes, a decrease in T-cytotoxic lymphocytes (CD8+) and nitro blue tetrazolium (NBT test), as well as an increase in NK cells and phagocytic activity of monocytes, more than 5 years — eosinophilia.

Conclusion. Common features of rearrangement of the immune system in opisthorchiasis: inflammatory changes in the hemogram, activation of humoral immunity with parallel suppression of the cellular component of the immune system, and increased phagocytosis.

Aim. To identify and compare the morphological, hemostatic and hemostasiological consequences of intravenous administration of tranexamic acid and fibrin monomer in controlled liver injury against drug-induced thrombocytopathy.

Methods. The morphological features of fibrin formation in the area of liver injury after spontaneous bleeding arrest combined with the indicators of blood loss in the animals treated with intravenous placebo, tranexamic acid or fibrin monomer was studied in 69 male rabbits. The effects of these drugs were assessed against thrombocytopathy associated with the combined use of acetylsalicylic acid and clopidogrel. Platelet number and function (adnosine diphosphate-induced aggregation), the data of thromboelastometry and calibrated automated thrombogram, fibrinogen concentration and D-dimer level were considered in the blood test. The feature distribution in the samples was assessed using the Shapiro–Wilk test. Depending on the distribution, Student's t-test, Mann–Whitney U test or Wilcoxon signed-rank test were used to test for a significant difference between the features. Differences in mortality rate were established by using Fisher's exact test. The differences were considered statistically significant at p <0.05.

Results. A model of thrombocytopathy which showed decreased platelet aggregation function (by 4.5 times), increased blood loss (by 40%), and high mortality (53.9%) was reproduced. Only a small accumulation of thrombotic material was noted on the injured surface of such animals. The use of tranexamic acid led to decreased post-traumatic bleeding (2.5 times) and animal mortality (20%). The latter was provided on the wound surface by increasing the thickness of both thrombotic deposits and fibrin strands. When fibrin monomer was used, the phenomenon of an overcompensated decrease in blood loss (by 6.7 times) accompanied by zero mortality was noted despite a pronounced decrease in platelet aggregation. The maximum increase in the thickness of thrombotic material and fibrin strands was morphologically determined in the injury area compared with other animal groups.

Conclusion. Morphological features of traumatic hemostatic effect at the injured area when using tranexamic acid and fibrin monomer have a number of differences despite the similarity of the achieved results in minimizing blood loss.

Aim. To analyze the biochemical changes in the cells of the heart muscle, liver and pancreas, as well as to establish their pathogenetic significance in diet-induced experimental hypercholesterolemia.

Methods. The study was conducted on 65 outbred male rats. During the experiment, the animals were divided into groups: the first (control, n=30) — animals that were kept on a general vivarium diet; the second (experimental, n=35) — animals with diet-induced hypercholesterolemia for three months by keeping on a special diet. At the end of the experiment, the concentrations of pyruvic acid, lactate, reduced glutathione, the activity of glutathione reductase, and glutathione peroxidase were determined in the tissues by using biochemical methods. The Student's t-test was used for the experimental data of the samples after normality testing.

Results. The analysis of energy metabolism indicators in animals with hypercholesterolemia relative to the control group revealed a lower level of pyruvic acid in the heart muscle (0.29±0.03 mmol/mg protein; p ≤0.05) and liver (0.25±0.02 mmol/mg protein; p >0.001). A significantly higher lactate level was recorded in all tissues, most pronounced in the liver (6.73±0.6 mmol/mg protein; p ≤0.001). The results obtained indicate the predominance of the anaerobic glycolysis in the tissues and the accumulation of incomplete-oxidation products. The study of the key glutathione-linked enzymes in animals with hypercholesterolemia relative to the control showed a lower activity of glutathione reductase in the pancreas — 0.52±0.05 mmol/mg protein/min (p ≤0.001), as well as its higher activity in the liver — 0.297±0.03 mmol/mg protein/min (p ≤0.001) and heart — 13.58±1.4 mmol/mg protein/min (p >0.001). The activity of glutathione peroxidase and reduced glutathione in all organs remained practically unchanged, or the differences were insignificant. This trend indicates a violation of the antioxidant defense system and oxidative stress.

Conclusion. Changes in the metabolic link of adaptive-compensatory responses in the cells of the heart muscle, liver, and, most pronounced in the pancreas, indicate the role of the pancreas as a “target organ” in the pathogenesis of diet-induced hypercholesterolemia.

Aim. To determine the left atrial dimensions, their ratios and relationships that characterize anatomy for left atrium structure in the normal human adult using the model of the atrial end-diastolic phase.

Methods. We studied 54 heart specimens of subjects aged 35–88 years who died from non-cardiac causes. The atrial end-diastolic phase was modeled by filling a specimen fixed in 1% formalin with liquid silicone. After silicone hardened, we performed morphometric measurements by a caliper. The data were processed by using a cluster, correlation and variance analysis. For pairwise comparison, we used the Mann–Whitney U-test or a ­two-sided t-test.

Results. The article presents mean, standard deviation, median, 25th percentile and 75th percentile and coefficients of variation for the length, width and sagittal size of the left atrium, as well as the values of the distances between the pulmonary vein orifices, which characterize the dimensions of the left atrium posterior wall. Based on the left atrial size differences and their ratios, the specimens were divided into three clusters. The first (n1=23) and second clusters (n2=10) were represented by hearts with a cubic atrium; the second group differed from the first in the larger size of the left atrium. The third cluster (n3=21) included the hearts in which the largest left atrium size was the width, so the shape of the atria resembled a parallelepiped. The typical number of the pulmonary vein ostia we found in 91% of the specimens. The posterior wall of the left atrium, with a common number and topography of the ostia, were rectangle or an unequal trapezium in shape. We analyzed correlations between the sizes of the heart, left atrium and its posterior wall. We concretized the conceptual apparatus concerning the nomenclature and terminology of the left atrium anatomical structures.

Conclusion. Based on the size ratio, two shape variations of the left atrium body can be identified: cubic or parallelepiped; cubic atria can be divided into large and small; the co-directional dimensions of the left atrial body and its posterior wall showed the strongest correlations.

High rates of cancer incidence and mortality from malignant neoplasms remains an urgent health problem. The development of the most effective therapeutic algorithms is required to improve the survival of cancer patients. An important condition for the discovery of new anticancer drugs and their translation into clinical practice involves the ability to model tumor growth, reproduce the characteristics of human disease, and evaluate measurable effects of pharmacological substances in laboratory facilities. Xenograft models established by direct implantation of fresh tumor tissue samples from individual patients into immunodeficient mice are considered suitable for both preclinical trials and for solving fundamental problems in oncology. The review highlights the significance of patient-­derived xenograft models as a platform with high predictive value and the prerequisites that make them the preferred tool for research in cancer biology. The most important methodological aspects in the creation of these models are considered. Methods for obtaining and preparing biological tumor samples for xenotransplantation are discussed. The significance of the immune status, as well as the phenotypic and genetic characteristics of recipient animals, is described. The article presents the limitations of animal models associated with their immunodeficiency status and ways to overcome them. The principles for choosing xenotransplantation sites (heterotopic and orthotopic) and their advantages and disadvantages are discussed. In conclusion, we emphasize the need to continue the work on optimizing PDX (Patient-Derived Xenograft) models to overcome their limitations and to obtain the most reliable and valuable research results in oncology.

The review looked at the issues of tumor heterogeneity in breast cancer. Tumor heterogeneity is classified according to the main feature demonstrating regional differences within a tumor (for example, heterogeneity of clinical manifestations, histological heterogeneity, heterogeneity of protein expression, etc.) and by tumor regions (differences between primary tumors and metastases, differences between cell clones within a single tumor node, etc.). Temporal heterogeneity is also distinguished, which manifests itself in the clonal evolution of tumor cells. The review covers the heterogeneity in the expression of four biomarkers from the “gold standard” for immunohistochemical staining of breast cancer: estrogen receptors, progesterone receptors, Her2/neu and Ki67 in primary tumor tissue and regional metastases. According to various studies, discordance in estrogen receptor status of primary tumor cells and metastases was observed with a frequency of 4 to 62%, progesterone receptors — from 12 to 54%, Her2/neu — from 0 to 24%, Ki67 — from 4 to 39%. The results of studies of changes in the expression levels of individual markers in breast cancer metastases, as well as the heterogeneity of surrogate subtypes of tumor tissue in metastasis, are briefly described. Possible reasons for heterogeneity in the expression of key prognostic and predictive markers by primary tumor and metastatic cells, such as artificial factors at the preanalytic and analytic stages of the study, polyclonality of the primary tumor before metastasis, clonal evolution of tumor cells during metastasis, selection of tumor clones under the therapy are highlighted.

Aim. To study the indicators of industrial injuries and occupational morbidity in the Russian Federation and the effectiveness of measures for the professional rehabilitation of injured workers in the context of the implementation of state programs aimed at enhancing the labor force and employment.

Methods. The analysis of statistical indicators on the number of workers, insured and injured at work from 2007 to 2018 and the results of measures for victim rehabilitation between 2014 and 2019, using data from Rosstat, reporting form No. 7 — social security and open data of the social insurance fund. Descriptive statistics were used in the analysis.

Results. The level of employment of disabled people planned by the Government of the Russian Federation by 2020 at the level of 40% in relation to people who are injured at work has not been achieved. At the same time, about 80% of the injured person had mild and moderate dysfunctions, about 50% were of working age. Against this background, employment at the level of 0.2 to 6.6% per year indicates the insufficient effectiveness of vocational rehabilitation. In most EU countries, where the return to work rate for work-injured people exceeds 90%, the employer and the insurer jointly participate in the professional rehabilitation of the injured, applying and financing all the necessary organizational and rehabilitation measures. In the Russian Federation, measures for occupational adaptation, maintenance of employment and the creation of special jobs are not subject to reimbursement from insurance funds, only educational events are financed. An employer who has caused harm to the health of work-injured is not economically interested in restoring his professional status. The authors encouraged to amend the regulations of the Russian Federation to ensure financing of the entire range of measures for vocational rehabilitation and the economic interest of employers in restoring the occupational status of work-injured people.

Conclusion. Despite the favorable decreasing trend of industrial injuries and occupational morbidity at the enterprises of the Russian Federation over the past 12 years, the number of industrial injuries with permanent disability remains high, and the effectiveness of their vocational rehabilitation is low, which requires an expansion of the list of measures for vocational rehabilitation financed from the social insurance fund and ensuring the economic interest of employers in restoring the professional status of work-injured people.

Using a clinical example, the article draws the attention of doctors to the problem of the prolonged QT interval (“long QT”) and the related problem of fainting (syncope). Syncope is a component of long QT syndrome, and syncope is a precursor of sudden cardiac death. However, syncope in a patient with long QT syndrome may have pathogenesis that is completely unrelated to abnormalities of cardiac ion channels. In other words, such a patient may have a second disease as a syntropy relates to prolonged QT interval, to an extent mimicking long QT syndrome. The presented medical history of a 33-year-old patient S. shows the complexity of differential diagnosis of the causes of syncope. The crucial part in the diagnosis, in addition to the clinical picture, was the so-called “tilt test”, little-known to general medical practice, as well as the laboriousness of making a final diagnosis of the long QT Syndrome type 2, which required a molecular genetic study — whole-exome sequencing. Patient S. had vasovagal syncope that not associated with long QT syndrome, but she has a risk of sudden cardiac death, and the article identifies therapeutic and other measures to reduce this risk.

Aim. To analyze the current practice for the surgical treatment of destructive acute appendicitis complicated by typhlitis and periappendicular abscess.

Methods. This study analyzed the treatment outcomes in 84 patients with acute destructive appendicitis aged 18 to 79 years who were treated in the Department of Surgery No. 2 of the City Clinical Hospital No. 7 of Kazan between 2016 and 2021 years. According to the method for completion of surgical intervention, patients were divided into 2 groups, similar in age, duration of the disease and morphological changes in the appendix. In the comparison group, 54 patients had the surgical intervention completed by gauze-glove drainage of the appendix bed. In 30 patients of the main group, the appendix stump and the adjacent intestinal wall was covered with a Tachocomb plate. Then the VAC system with the Vivano device and supplies from “Hartmann Group” (Germany) was connected. The statistical significance of the differences between the indicators was assessed by using the Student's t-test.

Results. The analysis of the surgical techniques used showed that in the main group, postoperative wound complications decreased by 3 times (23.3% of patients, p=0.04), intra-abdominal fluid collections decreased by 2 times (6.7% of patients, p=0.02), the hospital lengths of stay decreased by 1.8 times (p=0.02) compared with the comparison group.

Conclusion. The use of ligature appendectomy in combination with plastic closure of the appendix stump with a TachoComb and the technology of local vacuum-assisted laparostomy in patients with destructive appendicitis complicated by periappendicular abscess contributes to a 3-fold reduction in wound postoperative complications and reduces the hospital lengths of stay in this group of patients by 1.8 times.

Aim. To assess the effectiveness of indicators of lipid peroxidation and the activity of antioxidant system enzymes in the early diagnosis of metabolic disorders.

Methods. The study included 269 women of fertile age with primary obesity. The control group consisted of 35 women. The clinical examination included identification of the type of obesity, whole-body fat percentage, the level of glycemia and the index of insulin resistance, biochemical markers of lipids, hormones (leptin and insulin), malondialdehyde and enzyme activity (peroxidase and catalase). The statistical significance of the differences was determined by using the inversion test. Spearman's rank correlation coefficient was used to assess the degree of relationship between quantitative characteristics, and scatter diagrams were used to compare two variables (Statistica software version 10.0).

Results. A statistically significant increase in basal and stimulated immunoreactive insulin was found in obese patients compared with the controls (p <0.01). Stimulated immunoreactive insulin levels, insulin resistance score (HOMA-IR) and the level of leptin in the group of patients with android obesity was higher than in the group with gynoid obesity (p <0.01). The relationship between the concentration of serum malondialdehyde and whole-body fat percentage was found to be more significant (r=0.412; p <0.001) than the relationship with the type of obesity (r=0.257; p <0.01). Positive correlations were found between serum malondialdehyde and insulin (r=0.35; p <0.001) and leptin (r=0.32; p <0.001) levels. The relationship between the concentration of serum malondialdehyde and the activity of enzyme systems was also noted. The activity of lipid peroxidation was higher in the group of patients with android obesity (malondialdehyde >3.3 μmol/L) compared with the group of patients with gynoid obesity. In the same group, a higher activity of enzyme systems was noted.

Conclusion. An increase in the concentration of serum malondialdehyde and the activity of enzyme systems should be considered as indicators of a high risk of developing metabolic syndrome.

Aim. To analyze heart rate variability of patients with paroxysmal atrial fibrillation and identify electrophysio­logical phenotypes of the disease by using methods of exploratory analysis of twenty-four-hour electrocardiographic (Holter) recordings.

Methods. 64 electrocardiogram recordings of patients with paroxysmal atrial fibrillation were selected from the open Long-Term Atrial Fibrillation Database (repository — PhysioNet). 52 indices of heart rhythm variability were calculated for each recording, including new heart rate fragmentation and asymmetry indices proposed in the last 5 years. Data analysis was carried out with machine learning methods: dimensionality reduction with principal component analysis, hierarchical clustering and outlier detection. Feature correlation was checked by the Pearson criterion, the selected patient’s subgroups were confirmed by using Mann–Whitney and Student's tests.

Results. For the vast majority of patients with paroxysmal atrial fibrillation, heart rate variability can be described by five parameters. Each of these parameters captures a distinct approach in heart rate variability classification: dispersion characteristics of interbeat intervals, frequency characteristics of interbeat intervals, measurements of heart rate fragmentation, indices based on heart rate asymmetry, mean and median of interbeat intervals. Two large phenotypes of the disease were derived based on these parameters: the first phenotype is a vagotonic profile with a significant increase of linear parasympathetic indices and paroxysmal atrial fibrillation lasting longer than 4.5 hours; the second phenotype — with increased sympathetic indices, low parasympathetic indices and paroxysms lasting up to 4.5 hours.

Conclusion. Our findings indicate the potential of nonlinear analysis in the study of heart rate variability and demonstrate the feasibility of further integration of nonlinear indices for arrhythmia phenotyping.

Since the foundation of the Ural State Medical University (USMU), the importance of scientific activity in the training of specialists with higher medical education has been determined. A contribution to the history of medical science in the Urals since the 30s of the twentieth century was made by those who began work at the Sverdlovsk State Medical Institute, whose discoveries made it possible to find new methods of diagnosis and treatment, to identify the causes of any disease. For 90 years, the results of the activities of representatives of the established scientific directions and schools of Ural State Medical University have been used in the educational process and healthcare. The article describes the promotion of scientific activity of Ural State Medical University and its productivity over the previous decade. We analyzed reports on research activities for 2010–2020, materials based on the results of monitoring the effectiveness of Ural State Medical University, scientometric databases “Russian Science Citation Index” (RSCI), Web of Science, Scopus. Along with the development of traditional medical research areas and schools, the university researches in the areas of scientific medical platforms, cooperates with leading scientific, educational and medical organizations. The development of personalized medicine, digital medicine, reconstructive medicine, as well as the use of cellular technologies, and the fight against infectious diseases are highlighted among the topical areas. Over the current decade, the number of publications indexed in international abstract databases has increased 4 times in Scopus, 2 times in Web of Science, and 2.6 times in RSCI. The total number of citations of articles over five years (2016–2020) in Scopus was 990, Web of Science — 766. The number of articles included in the list of the Higher Attestation Commission under the Ministry of education and science of the Russian Federation, for a number of years on average — 456. There is the dynamic development of the scientific activity of Ural State Medical University with a focus on cooperation with leading research teams of other organizations, the implementation of research on a state assignment, accompanied by a significant increase in publication activity.

23 августа исполнилось 60 лет доктору медицинских наук, профессору, Андрею Юрьевичу Анисимову. Андрей Юрьевич — один из ведущих специалистов в Республике Татарстан в области организации и управления хирургической помощью, неотложной хирургии и хирургии экстремальных состояний. Вся его трудовая деятельность связана с этим разделом медицины, сначала в качестве хирурга, затем — в качестве организатора здравоохранения и, наконец, — в качестве преподавателя высшей медицинской школы.

Эсликарбазепина ацетат — это противоэпилептическое лекарство, которое может быть добавлено (так называемое «дополнительное» лечение) к лечению людей, которые принимают другие противоэпилептические лекарства, но у них продолжаются приступы (так называемая лекарственно-устойчивая эпилепсия). В этом обзоре рассматривалось, насколько хорошо действует эсликарбазепина ацетат при использовании в качестве дополнительного лечения, а также некоторые из потенциальных побочных эффектов этого лекарства.

Мы изучили доказательства о способах повышения физической активности у людей с нервно-мышечными заболеваниями. Мы включили только те исследования, в которых физическую активность оценивали как исход. Для ответа на этот вопрос мы собрали и проанализировали все соответствующие исследования.