Factors of the educational process and their influence on the formation of the health of schoolchildren within the reforming the system of general education (review) Suvorova A.V., Iakubova I.Sh., Meltser A.V., Khurtsilava O.G. 4
Comparative characteristics of the non-carcinogenic risk to population health during low-temperature and high-temperature disposal of medical waste Mironenko O.V., Khurtsilava O.G., Kiselev A.V., Fedorova E.A., Obukhov D.A. 13
DIAGNOSIS, TREATMENT, EPIDEMIOLOGY, PREVENTION OF DISEASES
Аnkle arthrodesis: current status of the problem (review)
Khominets V.V., Mikhailov S.V., Zhumagaziev S.E., Shchukin A.V. 23
Disorder of subchondral bone remodeling and activation of lipid peroxidation in the early osteoarthritis pathogenesis Belova S.V., Gladkova E.V., Ulyanov V.Yu. 34
Possibilities of deescalating axillary lymph node dissection in breast cancer patients after neoadjuvant chemotherapy (review) Kurbanova M.G., Monogarova M.A., Damenia A.O., Bit-Sava E.M. 55
Еpidemiological features of infections caused by polyresistant microorganisms in cancer patients (review) Ignatova O.K., Antonova E.A., Aslanov B.I., Propastina V.Y. 61
Оral microbiome in patients feeding through a gastrostomy
Kuznetsova Y.V., Zavyalova A.N., Lisovskii O.V., Davletova L.A., Al-Hares M.M., Gavshchuk M.V., Dudurich V.V., Pak A.A. 68
Еffect of prenatal iron deficiency on the development of the nervous system in children (review) Melnikova I.Y., Chistyakova V.Y. 77
PUBLIC HEALTH, ORGANIZATION AND SOCIOLOGY OF HEALTH CARE
Prospects for improving the organization of oncological care on the basis of the SWOT-analysis of the current legislation (review)
Kurmangulov A.A., Zadorkina T.G., Kononykhin А.А., Lyalina L.V. 86
CLINICAL LABORATORY DIAGNOSTICS
Laboratory evaluation of the anticoagulant therapy effect: comparative characteristics of the thrombodinamics assay and fnti-Xa activity measurement
Startseva O.N., Vavilova T.V., Kornev V.I., Zybina N.N. 97
Improvement of the quantitative assessment methods of superoxide dismutase activity in the erythrocyte mass Dadali Yu.V., Kosman V.M., Faustova N.M., Karlina M.V., Makarova M.N., Makarov V.G. 103
TO AUTHORS ATTENTION
HYGIENE
FACTORS OF THE EDUCATIONAL PROCESS AND THEIR INFLUENCE ON THE FORMATION OF THE HEALTH OF SCHOOLCHILDREN WITHIN THE REFORMING THE SYSTEM OF GENERAL EDUCATION (REVIEW)
A.V. Suvorov, I.Sh. Iakubova, A.V. Meltser, O.G. Khurtsilava North-Western State Medical University named after I.I. Mechnikov. Russia, 191015, Saint-Petersburg, Kirochnaya street, 41 Abstract
The continuous reforming of the general education system, which has been going on for more than half a century, was carried out without taking into account the negative trends in the health status of the child population, age- and sex related morphofunctional, physiological and psychological factors of children and adolescents. The constant increase in the volume and complexity of the studied programs created a problem of overworked schoolchildren being in a state of chronic stress, where the education success was achieved by intensifying of their mental activity within a shortage of study time.
In the last twenty years, additional factors of the intensification of the learning process have been formed - the widespread use of electronic learning tools in the classroom (interactive whiteboards, readers, personal computers, laptops, smartphones) and the Internet, the uncontrolled use of which contributes not only to the growth of school-related pathology, but also to an increase in the level of aggressiveness, anxiety, hostility, social stress formation and a decrease in the stress resistance.
In the next decade due to the transition to modern digital technologies in the general education system, the relevance of scientific research in the field of hygiene of children and adolescents is justified by the need to develop hygiene requirements for save to health and effective to learning use of electronic learning tools and distance technologies; and the development of health-saving technologies. Key words: general education, reforms, educational process, schoolchildren's health status, physical development, health groups, in-depth medical examination, electronic educational resources, distance learning technologies.
COMPARATIVE CHARACTERISTICS OF THE NON-CARCINOGENIC RISK TO POPULATION HEALTH DURING LOW-TEMPERATURE AND HIGH-TEMPERATURE DISPOSAL OF MEDICAL WASTE
O.V. Mironenko, O.G. Khurtsilava, A.V. Kiselev, E.A. Fedorova, D.A. Obukhov North-Western State Medical University named after I.I. Mechnikov, Russia, 191015, Saint Petersburg, Kirochnaya street, 41 Abstract Introduction. The article is devoted to the study of the impact on the population health of chemicals in the atmospheric air resulting from the incineration of medical waste and the use of autoclaving technologies for the disposal of medical waste. Aim of the study was to conduct a comparative analysis of the non-carcinogenic risk to the health of the population living in the area affected by emissions from low-temperature neutralization plants and from enterprises using various technologies for medical waste incineration, and also to propose a reasonable laboratory control program when using these technologies. Materials and methods. It was analyzed and ranked chemicals comprising industrial emissions from medical waste incinerators and medical organizations using local installations for low-temperature medical waste disposal by autoclaving, followed by grinding. Emission dispersion modelling with calculation of maximum surface concentrations was carried out, based on the selected priority pollutants an assessment of non-carcinogenic risk to the health of the population living in the zone of influence of technologies was performed. Results. According to the analysis results non-carcinogenic health risks from medical waste incineration enterprises showed the likelihood of developing adverse effects on organs and systems, risk levels were assessed as unacceptable for public health. During the operation of low-temperature exposure facilities, the levels of non-carcinogenic risk were assessed as acceptable. Conclusion. Based on the data of instrumental laboratory control of emissions from technologies of high-temperature and low-temperature medical waste disinfection, the structure of the main components polluting the atmospheric air depending on the composition of the waste was determined. With the use of the calculation and the modeling method, the priority chemical compounds were substantiated for inclusion in the industrial laboratory control program and the system of environmental protection measures for the purpose of regular monitoring. This study demonstrates the benefits of low-temperature waste disposal compared to high-temperature methods in the context of the impact of non-carcinogenic risk on public health. Key words: public health risk assessment, non-carcinogenic risk, atmospheric air, waste disposal, medical waste, incineration technologies; contaminants, autoclaving.
DIAGNOSIS, TREATMENT, EPIDEMIOLOGY, PREVENTION OF DISEASES
ANKLE ARTHRODESIS: CURRENT STATUS OF THE PROBLEM (REVIEW)
V.V. Khominets, S.V. Mikhailov, S.E. Zhumagaziev, A.V. Shchukin S.M. Kirov Military Medical Academy. Russia, 194044, Saint-Petersburg, AkademikaLebedeva Street, 6 Abstract Introduction. The treatment of patients with end-stage ankle arthritis continues to be an urgent problem in traumatology and orthopedics. The method of choice ofpatients’treatment with this pathology is ankle arthrodesis. The aim of the study is to present a brief historical background and current trends in improving ankle arthrodesis operations in the treatment of patients with terminal stages of ankle deforming arthritis based on the analysis of medical literature. Material and methods. The review included 94 papers by domestic and foreign authors during 1950-2023. The search was carried out in electronic scientific databases PubMed, Google Scholar, Science Research Porta, eLIBRARY and Cyber Leninka. Results. Various approaches used to perform ankle arthrodesisdepending on the condition of the soft tissues, the preferences of the surgeon and his experience, as well as on the method of fixation. A variety of options for osteoplastic materials have been proposed to increase the incidence of ankylosis of the ankle joint. Despite the development of various implants (screws, plates, intramedullary rods, external fixation devices), the search for the optimal fixator and technique is currently ongoing. Conclusion. Despite the constant improvement of methods of ankle arthrodesis in the treatment of patients with end-stagestages of deforming arthritis, this problem still remains relevant. Keywords: ankle joint, anklearthritis, ankle arthrodesis.
DISORDER OF SUBCHONDRAL BONE REMODELING AND ACTIVATION OF LIPID PEROXIDATION IN THE EARLY OSTEOARTHRITIS PATHOGENESIS
S.V. Belova, E.V. Gladkova, V.Yu. Ulyanov
Scientific Research Institute of Traumatology, Orthopedics and Neurosurgery,Saratov State Medical University. Russia, 410002, Saratov, N.G. Chernyshevskogo street, 148
Abstract Introduction. Despite the recent achievements in diagnostics and treatment of osteoarthritis, its molecular mechanisms have not been fully revealed and there is no effective methodology for the complete treatment and management. The aim of the study was to investigate the impact of subchondral bone remodeling and lipid peroxidation in the pathogenesis of the early knee osteoarthritis. Materials and methods. All patients underwent X-ray examination of the knee joints. The state of subchondral remodeling was assessed by changes in serum concentration of resorptive indicators – C-terminal telopeptides of type I collagen and pyridinoline. The bone formation was defined by the activity of bone alkaline phosphatase.The lipid peroxidation was represented by the intensity of lipid hydroperoxides and serum malondialdehyde. The total activity of antioxidant system was assessed by the overall antioxidant status. The cellular enzyme link of the antioxidant system was studied by investigating the degree of total activity of four superoxide dismutase types and catalase. Results and discussion. The examined patients had the pronounced disorders of subchondral bone remodeling in early knee osteoarthritis manifested by an increase in markers of bone formation (bone alkaline phosphatase) and bone resorption (pyridinoline and C-terminal telopeptides of type I collagen). This was associated with an increasing activity of lipid peroxidation as reflected by the significantly increased level of lipid hydroperoxides and malondialdehyde.There was also an apparent increase in the total activity of four types of superoxide dismutase as well as a decrease in catalase activity along with the insignificant drop in the overall activity of the antioxidant system. Conclusion. These findings could be of use in objectifying the evaluation of patients with early knee osteoarthritis when choosing ways to correct their condition. Key words: osteoarthritis,early stage, subchondral bone remodeling, lipid peroxidation.
MOLECULAR SUBCLASSIFICATION OF ENDOMETRIAL CANCER: AGE ASPECTS
Yu.E. Gavrish1,2, A.S. Artemieva1, A.A. Sidoruk2,4, A.N. Baltrukova2, E.A. Ulrikh1,2,3, I.V. Berlev1,2, A.F. Urmancheeva1,2 1N.N. Petrov National Medicine Research Center ofoncology. Russia, 197758, Saint-Petersburg, Leningradskaya street, 68 2North-Western State Medical University named after I.I. Mechnikov. Russia, 191015, Saint-Petersburg, Kirochnaya street, 41 3Almazov National Medical Research Centre. Russia, 197341, Saint-Petersburg, Akkuratova street, 2 4Leningrad Regional Clinical Oncological Dispensary named after L. D. Roman. Russia, 191014, Saint-Petersburg, Liteiny prospect, 37-39 Abstract Introduction: The study results within The Cancer Genome Atlas (TCGA) program initiated a new phase towards the personalization of endometrial cancer (EC) treatment. In this regard, it seems interesting whether there are age-related features of endometrial cancer within molecular subgroups, or is the prognosis of the disease determined by the presence of certain molecular genetic changes? The aim of the study was to perform the immunohistochemical evaluation of DNA mismatch repair proteins and p53 in endometrial tumors, their influence on the course and prognosis of EC, including in the age-related aspect. Materials and methods.The study included 245 samples of endometrial tumors, divided into three subgroups: 1st - tumors with dMMR, n=88, 2nd - tumors with p53abn, n = 19, 3rd - pMMR/p53wt , n = 138. Results: In the dMMR and pMMR/p53wt subgroups, endometrial tumors in most cases are low-grade endometrioid carcinomas detected at the stage of a localized process (I-II according to FIGO), characterized by similar survival rates. The inclusion of the age factor in the statistical analysis demonstrates a statistically lower survival rate among persons ≥70 years of age in the pMMR/p53wt subgroup. In the p53abn subgroup, high-grade tumors prevailed due to the predominance of non-endometrioid carcinomas in 1/3 of all cases detected at stages III-IV of the disease, characterized by an unfavorable prognosis. Conclusions: Age does not affect the prognosis of EC in the subgroup with dMMR, but is determined by the presence of corresponding changes. The inclusion of the age factor in the statistical analysis shows a worse prognosis for older patients in the pMMR/p53wt subgroup. Concerning the p53abn subgroup, unambiguous conclusions couldn’t be made, which is associated with a small number of cases in this subgroup (n=19), the majority of which (17/19) occurred in patients ≥ 70 years old. Keywords: endometrial cancer, morphology, elderly, immunohistochemistry, DNA mismatch repair proteins, p53 .
POSSIBILITIES OF DEESCALATING AXILLARY LYMPH NODE DISSECTION IN BREAST CANCER PATIENTS AFTER NEOADJUVANT CHEMOTHERAPY (REVIEW)
M.G. Kurbanova1, M.A. Monogarova 1, A.O. Damenia 1, E.M. Bit-Sava 1,2 1Petersburg clinical scientific and practical center for specialised types of medical care (oncological). Russia, 197758, Saint -Petersburg, Pesochny settlement, Leningradskaya street, 68A, lit. A 2 Saint- Petersburg state pediatric medical University, Department of Oncology. Russia, 194100, Saint- Petersburg, Litovskaya street, 2 Abstract
The accuracy of sentinel lymph node biopsy in patients with (cN+) treated with neoadjuvant chemotherapy depends on the number of sentinel lymph nodes removed and whether the dual indication method is used. In order to act according to St. Gallen International Consensus Guidelines, axillary lymph node dissection is required in a significant number of patients, including those with a complete pathomophological response (pCR), if 3 sentinel lymph nodes are not removed. In these circumstances, in the absence of axillary lymph node dissection, removal of the clipped lymph node in addition to the sentinel lymph node may be the best surgical strategy after neoadjuvant chemotherapy.
Randomized trials (MARI, ILINA, RISAS, NSABP-B27) evaluated the negative predictive value of sentinel lymph node biopsy and targeted lymph node dissection after neojuvant chemotherapy. Category (cN+) was confirmed by fine needle biopsy, the rate of identification and detection of residual tumor of the labeled lymph node in combination with sentinel lymph node biopsy after neoadjuvant systemic therapy was assessed. Keywords: neoadjuvant therapy, sentinel lymph node biopsy, targeted axillary lymph node dissection, clipped lymph node.
EPIDEMIOLOGICAL FEATURES OF INFECTIONS CAUSED BY POLYRESISTANT MICROORGANISMS IN CANCER PATIENTS (REVIEW)
O.K. Ignatova1,2, E.A. Antonova2, B.I. Aslanov2, V.Y. Propastina3 1N.N. Petrov National Medical Research Center of Oncology, Russia, 197758, Saint-Petersburg, Leningradskaya street, 68 2North-Western State Medical University named after I.I. Mechnikov, Russia, 191015, Saint-Petersburg, Kirochnaya street, 41 3Kuban State Medical University, Russia, 350083, Krasnodar, Mitrofan Sedin street, 4 Abstract Introduction. In modern medicine, one of the important and unresolved problems is healthcare-associated infections causing significant economic damage to the healthcare system and burden patients' condition, reducing the effectiveness of treatment and increasing hospitalization periods. Cancer patients are at risk for healthcare-associated infections due to immunocompromised status combined with constant invasive diagnostic and therapeutic procedures, as well as prolonged hospitalization periods, creating a favorable environment for infection acquisition. The aim of the study was to analyze the current state of the problem of the spread of healthcare-associated infections in inpatient units of oncological hospitals and to study relevant measures for implementing infection prevention and control. Materials and methods. During the study, scientific papers of domestic and foreign authors containing information on healthcare-associated infections and measures to ensure epidemiological safety of medical activity in oncological hospitals were analyzed. Results. Cancer patients who receive high-tech medical care are at risk of developing healthcare-associated infections. The main factors predisposing to infections development are neutropenia and impairment of cellular and humoral immunity due to the use of chemotherapeutic and hormonal drugs, anatomical barriers disruptions (surgical interventions, implanted devices, etc.), and obstruction caused by tumor processes. Conclusion. Considering the high susceptibility of cancer patients to healthcare-associated infections, a multidisciplinary approach is necessary for prevention and treatment of these conditions. Proper organization of infection control is also necessary as it could prevent the majority of cases of healthcare-associated infections. Keywords: healthcare-associated infections, oncology, cancer, hospital flora, multidrug-resistant strains.
ORAL MICROBIOME IN PATIENTS FEEDING THROUGH A GASTROSTOMY
Y.V. Kuznetsova¹, A.N. Zavyalova¹, O.V. Lisovskii¹, L.A. Davletova¹, M.M. Al-Hares ¹, M.V. Gavshchuk¹, V.V. Dudurich², A.A. Pak³ ¹ Saint -Petersburg State Pediatric Medical University. Russia, 194100 Saint-Petersburg, Litovskaya street, 2 ² Limited liability company “Serbalab”. Russia, 199106, Saint-Petersburg, Bolshoy prospect V.O., 90, building 2, letter 3 ³ Saint- Petersburg State Budgetary Stationary Institution of Social Services “Boarding house for children with mental disabilities No. 4”. Russia, 196620, Saint-Petersburg, Pavlovsk, Elizavetinskaya street, 9-15, lit. A, B, C, D
Abstract Introduction. Neurological patients with severe dysphagia require long-term gastrostomy nutrition. The oral microbiome of these patients has not been previously studied. The aim of the study was to analyze the oral microbiome in tube-fed children to determine the dependence of the oral microbiome on the standing time of the gastrostomy tube. Materials and methods. The study included 21 children aged 1-17 years with neurological disorders and dysphagia, they were divided into two groups depending on the standing time of gastrostomy tube: group 1 - up to a year, group 2 - more than a year. Comparison group comprises 12 children aged 1-17 years without neurological disorders nourishing by mouth. Oral fluid was studied followed by metagenomic sequencing of 16SrRNA.
Nonparametric method and median value were used for statistical processing. Results. The ratio of Firmicutes and Proteobacteria phyla changes significantly: the share of Firmicutes decreases, while Proteobacteria inceases. The number of representatives of the phyla Fusobacteriota, Campylobacterota significantly decreases (p<0.05) after the cessation of oral intake. Changes were observed in an increase in the number of microorganisms of the Gammaproteobacteria class, and a decrease in the representatives of the classes Coriobacteriia, Negativicutes, Campylobacteria and Fusobacteriia after the installation of a gastrostomy (p<0.05). Conclusion. Changes in the oral microbiome occur early after the cessation of oral feeding.The microbial biodiversity of the oral cavity in children fed through the gastrostomy is significantly lower (p < 0.05) than in children fed through the mouth. Keywords: microbiome, 16srrnk, oral cavity, gastrostomy, metagenomic sequencing, dysphagia.
EFFECT OF PRENATAL IRON DEFICIENCY ON THE DEVELOPMENT OF THE NERVOUS SYSTEM IN CHILDREN (REVIEW)
I.Y. Melnikova, V.Y. Chistyakova North-Western State Medical University named after I.I. Mechnikov. Russia, 191015, Saint- Petersburg, Kirochnaya street, 41 Abstract
Iron deficiency is the most common deficiency worldwide. The frequency of distribution according to WHO data in the population could be moderate – from 5 to 19.9%, average – from 20 to 39.9% and high – 40% or more. Women of reproductive age and young children are mostly affected by iron deficiency.
In the late prenatal and early postnatal periods, iron deficiency could result in long-term neuropsychiatric disorders continuing despite iron preparation treatment. Screening and treatment of iron deficiency in children is currently focused on detecting anemia rather than earlier markers of sideropenia. Anemia is the final stage of iron deficiency. In relation to the nervous system, a deficiency condition develops long before the onset of anemia due to the priority of the distribution of available iron in red blood cells compared to other organs. Iron deficiency in the brain, regardless of anemia, is responsible for adverse neurological effects. Early diagnosis and treatment of impending brain dysfunction at the pre-anemic stage are necessary to prevent neurological deficits. Currently available hematological indicators are not sensitive biomarkers of iron deficiency and brain dysfunction.
This review describes the features of iron metabolism in pregnant women, the connection of iron with the development of the fetal nervous system. It describes the neurocognitive and mental consequences of fetal iron deficiency. Key words: iron deficiency, pregnancy, iron deficiency anemia, hepsidin, iron regulation, hippocampus, psychological disorders, neurological disorders.
PUBLIC HEALTH, ORGANIZATION AND SOCIOLOGY OF HEALTH CARE PROSPECTS FOR IMPROVING THE ORGANIZATION OF ONCOLOGICAL CARE ON THE BASIS OF THE SWOT-ANALYSIS OF THE CURRENT LEGISLATION (REVIEW)
A.A. Kurmangulov1,2, T.G. Zadorkina3, A.A. Kononykhin1, L.V. Lyalina4,5 1 Tyumen State Medical University. Russia, 625023, Tyumen, Odesskaya street,54 2Tyumen Cardiology Research Center - branch of the Tomsk National Research Medical Center of the Russian Academy of Sciences. Russia, 625026, Tyumen, Melnikaite street, 111 3Immanuel Kant Baltic Federal University. Russia, 236041, Kaliningrad, A. Nevskogo street, 14 4Saint-Petersburg Pasteur Institute. Russia, 197101, Saint-Petersburg, Mira street, 14 5North-Western State Medical University named after I.I. Mechnikov. Russia, 195067, Saint-Petersburg, Piskarevsky prospect, 47
Abstract
The article presents the results of a scientific review on the methodology of the SWOT analysis of the current regulatory framework for the provision of oncological care to the population of the Russian Federation and develops recommendations for its improvement in order to reduce the incidence and mortality from malignant neoplasms. In the course of the SWOT analysis, the strengths, weaknesses, as well as opportunities and threats of the current regulatory framework for the provision of oncological care to the population were identified. The procedure for providing medical care to the population in case of oncological diseases is considered thoroughly. The following federal projects was analyzed: "Fight against oncological diseases", "Creation of the single digital circuit in healthcare based on the Unified State Health Information System", "Provision of medical organizations with qualified personnel". The state of resource support of the oncological service was studied, as well as the features of payment for oncological care and coding of oncological diseases in accordance with the international statistical classification of diseases and health-related problems. Key words: neoplasm, cancer care, strategic planning, register, lean production, national project, personnel shortage.
CLINICAL LABORATORY DIAGNOSTICS
LABORATORY EVALUATION OF THE ANTICOAGULANT THERAPY EFFECT: COMPARATIVE CHARACTERISTICS OF THE THROMBODYNAMICS ASSAY AND ANTI-XA ACTIVITY MEASUREMENT
O.N. Startseva1, T.V. Vavilova 1,2, V.I. Kornev1, N.N. Zybina1 1Nikiforov Russian Center of Emergency and Radiation Medicine, EMERCOM of Russia. Russia, 194044, Saint-Petersburg, Academica Lebedeva street,4/2 2Almazov National Medical Research Centre. Russia, 1973412, Saint- Petersburg, Akkuratova street, 2 Abstract Introduction. Low molecular weight heparins (LMWH) are widely used in preventing and treating venous thromboembolism complications, generally without laboratory control. However, some clinical settings may require heparins effect monitoring for efficient and safe anticoagulant therapy. The problem of heparins laboratory control has still been unsolved due to the absence of their effect onto hemostasis screenings and ambiguity of using integral tests comparing to anti-Xa activity measurement at treatment with heparins. The aim of thestudy is to conduct a comparative analysis of the results of integral thrombodynamics test and anti-Xa activity measurement in plasma for the patients of multi-disciplinary in-hospital undergoing LMWH therapy. Materials and methods.The study included 40 patients aged from 37 to 69 years diagnosed with acute coronary syndrome, acute cerebrovascular disease. All patients underwent anticoagulant therapy with LMWH at treatment doses depending on the body weight. Anti-Xa activity was measured using automatic coagulometer (Instrumentation Laboratory Company, Italy); clot growth velocity in thrombodynamics test was measured using the diagnostic laboratory system (HemaCore, Russia). The blood was sampled twice: at the peak action of the drug (3-4 hours after the injection) and at the end of its effect (before the next injection). The results were statistically processed using software package Statistica 10.0 (StatSoft Inc., USA). Results. At the peak action of the drug anti-Xa values were within the recommended range in 30 patients and were below the lower limit of the range in 10 patients, which might reflect the weak effect of the drug. The V parameter in thrombodynamics assay was above the upper limit of the recommended range for 6 patients from the group of 10 patients who’s anti-Xa activity had not reached the therapeutic values, while the rest 4 patients had this parameter within the recommended range. At the end point the clot growth velocity was lower than recommended in 4 patients, within the recommended range in 31 patients and higher in 5 patients. Conclusion.Thrombodynamics assay may be used as an additional method to assess the response formation after LMWH injection and it may guide the clinician regarding the anticoagulant therapy in case there is no possibility to measure anti-Xa activity. Keywords. Anti-Xa activity, thrombodynamics, monitoring of anticoagulant therapy.
IMPROVEMENT OF THE QUANTITATIVE ASSESSMENT METHODS OF SUPEROXIDE DISMUTASE ACTIVITY IN THE ERYTHROCYTE MASS
Yu.V. Dadali, V.M. Kosman, N.M. Faustova, M.V. Karlina, M.N. Makarova, V.G. Makarov Joint stock company «Research and Manufacturing Company «HOME OF PHARMACY». Russia, 188663, Vsevolozhski municipal district, Kuzmolovo, Zavodskaya street, build. 3/245 Abstracts Introduction. Quantitative assessment of the superoxide dismutase activity, as one of the most important enzymes of the enzymatic link of the antioxidant defense of the body, is often in demand during various preclinical pharmacological studies of the drug’s effectiveness, biologically active additives , as well as in clinical practice to assess the antioxidant status of the body in various pathological conditions (cardiovascular diseases, ischemia, hepatitis, diabetes mellitus, etc.). In laboratory practice, a technique for determining the total activity of superoxide dismutase in the erythrocyte mass of human blood and laboratory animals by spectrophotometric method is widely used, based on determining the degree of inhibition by the enzyme of the quercetin autooxidation reaction in an alkaline medium. Generally accepted recommendations provide for manual introduction of reagents into the wells of the tablet and simultaneous mixing of reagents with the start of the quercetin oxidation reaction. The use of an automatic injection system in modern flatbed analyzers could lead to a decrease in variability and an increase in the precision of measurement results. The aim of the study is to improve the methodology for determining the superoxide dismutase activity in the erythrocyte mass using an automatic injection system of reagents to increase its precision and to analyze the comparability of the results obtained in manual and automatic mixing of reagents. Materials and methods. The experimental work was performed using samples of erythrocyte mass hemolysates of intact laboratory animals (rats). Measurements under various conditions of reagent administration were carried out at a wavelength of 406 nm in kinetic mode on a ClarioStar ® microplate analyzer (BMG Labtech, Germany). Results and discussion. Differences were found in the results of measurements of the superoxide dismutase enzyme activity and the degree of inhibition of the quercetin oxidation reaction: under conditions of manual filling of the wells of the tablet, a significant excess (almost twice) of the values of the enzyme activity was observed compared with the results obtained using the automatic injection system. In the course of the performed study, the cause of these differences was identified, corrected and minimized by establishing the optimal sequence of reagent application, which was initially used in the "automatic injection" mode. In the course of the proposed sequential administration of reagents, both when filling the wells of the tablet manually and in the automatic injection mode, similar results were achieved with low variability and satisfactory and comparable precision (8.8-43.1% for the manual mode and 5.9-19.7% for the "automatic injection" mode). Conclusion. The method of quantitative determination of the superoxide dismutase enzyme activity within the performed study has been modified by using an automatic injection system of reagents and taking into account the proposed correction of their sequential administration. This technique could be used in preclinical biochemical and pharmacological studies of the enzymatic link of the antioxidant defense of the body for a more correct assessment of the medical drug’s effectiveness and dietary supplements in specific models of experimental pathologies, as well as in clinical researches. Keywords: antioxidant protection, oxidative stress, medical drugs, biologically active additives, enzyme, superoxide dismutase, activity, inhibition, modification, automatic injection.
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