Статьи журнала - Cardiometry
Все статьи: 527
Study of artificial aortic valve influence on hemodynamics by heart cycle phase analysis method
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The results of study of an artificial aortic valve by the heart cycle phase analysis are given in the paper. The main aim of the study is identifying the artificial aortic valve influence on cardiovascular system functions, the way and ranges of these functions change. The results of phase blood volume measurement and the numerical values that characterize the metabolic processes in heart muscles are given herein.
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Статья
Eukaryotic protein kinases are represented by a large superfamily of homologous proteins similar in structure of the catalytic (kinase) domain, consisting of 250-300 amino acids [3]. Most human protein kinases share a common fold consisting of an N-terminal lobe, consisting of a five-stranded β-sheet with an α-helix called the C-helix, and a C-terminal lobe comprising six α-helices. The active center is located between the two lobes and forms binding sites for adenosine triphosphate (ATP) and protein [4]. Protein kinases modify the functions of other proteins by phosphorylation, acting as elements of signaling pathways. Disorders and abnormalities in the activity of these enzymes give rise to the pathogenesis of many malignant neoplasms. Based on this fact, the targeted synthesis of some substances capable of selectively modifying the activity of protein kinases is an urgent task. The study of the process of interaction of molecules with the catalytic center of protein kinase by the method of molecular dynamics makes it possible to search for chemical structures of substances capable of inhibiting this enzyme [2]. Taking into account the high similarity of the structure of the catalytic domains of various human protein kinases, it is of scientific interest to develop a technique for modeling the molecular dynamics of the ligand-enzyme system, which allows predicting the spectrum of inhibitory activity against a set of protein kinases.
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Статья
The cytotoxicity of the synthesized conjugate was assessed in the cultivated Huh7 cells using the MTT test in co-incubation for 72 h in the concentration range from 4×10-2 µg/ml to 10 µg/ml. The toxicity was tested in vivo in the female DBA2 mice by an intraperitoneal injection of the test conjugate at a dose of 20 mg/kg, 25 mg/kg and 33 mg/kg (water for injectionused to dilute) followed by observation of the animals for 28 days. The DBA2 strain mice were intraperitoneally transplanted with the lymphocytic leukemia L1210 to study the antitumor activity of the above agent. The conjugate was administered at a dose of 24 or 12 mg/kg once 24 hours after the tumor transplantation. The efficacy was assessed by the criterion of increased survival (IS), and tolerability was evaluated by changes in the body weight of mice, some external signs, and the number of animals’ deaths from toxicity. Results. The IC50 values in the cultivated Huh7 cells were recorded to be 0.08±0.02 µg/ml. The doses tested in the mice did not show any toxic effects within 672 hours after the single dose use; no death cases in the mice were reported, and no special features were recorded in the autopsy. The maximum tolerated dose was determined to be above 33 mg / kg for the intraperitoneal administration. In the model of the lymphocytic leukemia L1210, the IS value was 60% (p function show_abstract() { $('#abstract1').hide(); $('#abstract2').show(); $('#abstract_expand').hide(); }
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Статья научная
Aims This paper deals with a study of central hemodynamics in 363 pediatric patients with burn shock as compared with a reference healthy children group in order to establish clinical value of the hemodynamic parameters for burn shock diagnostics and therapy. Materials and There is a new method applied to examine the functional status of the methods cardiovascular system with use of the medical equipment Cardiocode that is based on the method of the heart cycle phase analysis and capable of measuring parameters such as a stroke volume (SV), a circulation minute volume (CMV), systolic parameters (both a rapid ejection volume Vr.e. and a slow ejection volume Vs.e.), diastolic parameters (an early diastole volume Ve.d. and an atrial systole volume Va.s.), including a volumetric parameter characterizing the actual tonus of the ascending aorta (Va.a.). Results Age-related trends in the above volumetric parameters have been established herein. Specific features of the hemodynamic parameters in pediatric patients with burn shock have been identified. Conclusion Diagnostics of changes in the central hemodynamics in pediatric burn patients at their hospital admission provides reliable prediction tools for detecting shock well in advance and starting with an adequate intensive therapy.
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Статья научная
Aims The aim is to study the effect of simulated space flight factors on the human central hemodynamics and evaluate the effectiveness of colloid and crystalloid infusions in microgravity simulation using the Cardiocode method. Materials and methods Test subjects were six men aged 20 to 35 without chronic somatic diseases. Antiorthostatic hypokinesia with an angle of 15 ° (ANOH-15) simulated the weightlessness was used. Diuretics were used to simulate hypovolemia in the test individuals. During ANOH-15 the colloid and crystalloid intravenous infusions were applied. Central hemodynamics parameters were measured by Cardiocode method. Results Background quantitative and qualitative central hemodynamics parameters were obtained, several individual characteristics of blood flow regulation were identified. The effects of space flight factors, ground-based simulated with antiorthostatic hypokinesia, on the human hemodynamics were investigated. The efficacy of crystalloid and colloid infusions for the correction of central hemodynamics abnormalities in test subjects with hypovolemia in microgravity was studied. Conclusion The Cardiocode method allowed obtaining the information about the effects of simulated space flight factors and different infusion fluids on the human central hemodynamics. The efficacy of crystalloid and colloid infusions for the correction of central hemodynamics abnormalities in test subjects in microgravity was positively evaluated.
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Статья научная
Purpose - This article aims to study the employees’ behavior during organizational change and the effects of business theatre on the Kübler-Ross Model to boost the employees’ spirit so that the efficiency of an organization would increase. Design/methodology/approach - The authors revisit the insights from previous work on the role of organizational change and its effects on employees’ behavior. Classic KüblerRoss Model has been used in this study to analyze employees’ behavior during the change process. Findings - This article shows how business theatre can act as a healer and help employees overcome emotional turmoil. Eventually, the implementation of business theatre may shorten the time taken by the employees when they go through shock-denial-anger-bargaining-depression-acceptance-commitment phases of grief. Originality/value - The paper provides new insights into the role of business theatre in organizational change management. It focuses on the interrelationship between both, with the help of the conceptual framework of the Kübler-Ross Model, which explains employees’ behavior during the organizational change.
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Study of factors leading to poor sleep among management students
Статья научная
Sleep is the most important but often neglected element of an individual’s overall health and well-being. Lack of sleep or poor sleep can adversely affect health in an individual and lead to various diseases. At the same time, sleep problems are not uncommon among students. The factors leading to poor sleep among management students who have a comparatively tight schedule are still unclear. The paper aims to understand the factors leading to poor sleep among management students. The study has been focused on the management students (MBA’s) studying in the different management colleges of the state of Maharashtra. A total of 297 management students were surveyed. Apart from factor analysis, the Kessler distress scale was used for Measuring Psychological distress.52% of the respondents fell in the category of likely to have a mental disorder. Managements can draw inference from this and implement strategies to make sure this number reduces.
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Статья научная
The sedative activity of the zopnik herb on the model of prolongation of the sleeping action of barbiturate in white rats was studied. As a result of the study, it was found that, in terms of the ability to prolong urethane sleep, Mullein-shaped zopnik is equivalent to the well-known sedative - Regel’s zopnik herb. When studying the sleeping effect, it was shown that the Mullein-shaped zopnik herb does not cause signs of drowsiness compared to the control.
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Статья
Topicality. The altered glucose metabolism in cancer cells, known as the Warburg effect, is a new area of research of anticancer agents [1]. To date, many compounds have been identified that address the glucose metabolism. However, many of them failed at the early stages of clinical trials, demonstrating systemic toxicity [2, 3]. The glycolysis inhibitor iodoacetate (IA) has a good antitumor effect, but, like other glycolysis inhibitors, it has an unsafe profile. Liposomes (LS) are a good element to provide the required targeted delivery and reduce the systemic toxicity of drugs. The aim of our study was to identify the effect of iodoacetate encapsulation in liposomes made on its antitumor properties and assess the systemic toxicity thereof. Methods. LS were prepared by extrusion. The dose of IA encapsulated in drugs was quantified using high performance liquid chromatography. The toxic effect was assessed by biochemical blood markers. The antitumor and antimetastatic activity was studied in a Lewis carcinoma model using short-term (4 days) and two-week long-term regimens.
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Study of the effect made by interval hypoxic training on cardiac metabolism and hemodynamics
Статья
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Статья научная
This research aims to find out the status of trust the people of the world’s two prominent democracies - The United States of America, known worldwide as the most powerful democracy, and the Republic of India, known as the World’s Largest Democracy in the handling of the COVID-19 epidemic, that has gripped the entire world by storm. Also, the second objective of this study is to find out if the population of the two nations believe that their governments have actively used disinformation tactics - once thought to be used only by a despot or autocratic governments, on its populace to control the COVID-19 panic and hysteria surrounding it. This study also aims to understand the relationship between trust and disinformation, if any. The study aims to fulfill its objective via individual responses. The survey was conducted via Google Forms and was floated via social media apps like Face book, Linked In, Whatsapp, Instagram, and popular chat sites such as Omegle and Reddit.
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Succinate as a mobilization cue
Статья обзорная
Succinic acid, being a metabolite of the Krebs cycle and the end product of anaerobic transformations in mitochondria, functions outside mitochondria and cells as a regulatory signal. In the cytosol, micromolar amounts of succinate stabilize the transcriptional hypoxia-inducible factor HIF, which triggers the genes responsible for adaptation to hypoxia. Outside the cells, succinate activates the SUCNR1 receptor, which increases the concentration of intracellular calcium. The effect of short bursts of endogenous succinate accumulation and signaling after hypoxia/ischemia, or extreme glucose use from physical exercise should be distinguished from the effect of a permanently increased level of endogenous succinate under pathology (obesity, diabetes mellitus, chronic ischemia, succinate dehydrogenase damage). A short succinate signal triggers an adaptive response by an organism. Prolonged rise and highly elevated levels of endogenous succinate is a pro-inflammatory, damaging factor that can contribute to the progression of neoplasms. Use of succinate-containing compositions at a dose of 0.5-5 millimole can only provide a short signal. This is due to the positive effect of a number of succinate-containing agents.
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Systematic design of optimized pulse shape for transthoracic defibrillation
Статья научная
In the study conducted by us previously, it was found that not only the energy of the discharge, but also the amplitude of current, the pulse duration and its shape have their significant influence on the efficacy of defibrillation. Until now, no systematic approach to the comparison of the pulse shapes effectiveness has been available. An identification of the optimal pulse parameters for defibrillation has not only theoretical aspects but also engineering details in the design implementation. In order to conduct a complete pulse optimization, required is a multidisciplinary approach to determining boundary values and searching for further ways to improve the efficiency of electropulse therapy. An understanding of the relationship between the biphasic pulse parameters and the criteria for healthcare quality can make it possible to increase the survival rate of patients with ventricular fibrillation and ventricular tachycardia. The implementation of the current stabilization system in the defibrillator allows realizing an individual selection of the pulse energy defibrillation.
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It is known about numerous regulatory disorders in the body during the development of a malignant process. However, in this case, the natural mechanisms of the anti-tumor resistance remain poorly understood. The concepts on the systemic processes during the development of general nonspecific adaptational reactions of the body (AR): stress and anti-stress ARs, discovered by G. Selye and Russian scientists L.Kh. Garkavi, E.B. Kvakina and M.A. Ukolova, have contributed to the development of effective technologies for preventive and complementary therapy for the purposes of clinical oncology
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Testing Herzberg's two factor theory on millennials
Статья научная
This study tests Herzberg’s two-factor theory of motivation on working millennials. The purpose of the study is to evaluate what the assumptions and the findings of the original study hold for millennials. With the increasing trend of amalgamation of work life and personal life, job satisfaction and general job happiness have never been more on an individual’s personal life. This impact is far-reaching, with strong indications of affecting the employees’ physical, mental, and social health. In such a scenario, organizations need to keep their employees motivated and satisfied. For studying Herzberg’s two-factor theory of motivation on working millennials, we have selected respondents with work experience of at least one year. We have not restricted the study to any particular industry; hence our sample is across all industries. The type of sampling used was convenient sampling. From the analysis, we have found that for the concerned sample, hygiene factors tower above the motivating factors in terms of job satisfaction for millennials. From the data collection and analysis, we proved that both motivators and hygiene factors affect job satisfaction, unlike what has been said by Herzberg. This study will contribute to the exciting literature on motivation.
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The article is devoted to a novel noninvasive measurement of parameters of metabolic processes in the cardiac muscle fiber cells upon an original ECG processing. Theoretically substantiated is an original method of the ECG cardiac cycle phase analysis, which allows measuring the concentration of oxygen, lactate and phosphocreatine in arbitrary units in the cardiac muscle fiber cells in each cardiac cycle. The results of practical applications of the above cardiometric method for assessing the conditioning in a high-performance swimming athlete are discussed herein. Recommendations for a widespread use of the method in practice are discussed herein, too.
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The G.Poyedintsev - O. Voronova mathematical model of hemodynamics
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Aims The objective is to demonstrate the features of an original mathematical model of hemodynamics, developed by Russian researchers G.Poyedintsev and O.Voronova. Materials and methods The proposed original mathematical model of hemodynamics is based on the laws of the fresh hydrodynamic theory of the "third" fluid flow mode. Results As a result of the application of the above mathematical model of hemodynamics, an advanced method for noninvasive measuring of a complete set of hemodynamic parameters with the use of the cardiac cycle phase durations, implemented by the Cardiocode device, have been elaborated. Conclusion The unique method for noninvasive measuring of a complete set of hemodynamic parameters, which has been developed on the basis of the above mathematical model of hemodynamics, is a promising source for considerable expanding of diagnostics capabilities.
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It has long been thought who wants to be healthy and strong should go in for sports: do exercises, run, swim, participate in sports games and so on. Speaking about amateur sporting participants, the result of being vigorous, energetic, able-bodied and physically & emotionally attractive is important for us.
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The course of very severe aortic stenosis due to bicuspid aortic valve calcinosis in a young man
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In the young patients with bicuspid aortic valve, manifestation of aortic stenosis (AS) often remains silent. Asymptomatic very severe AS makes medical decisions challenging. For the better evaluation of AS severity and estimation the indications for the surgical treatment any stress test is preferable. We report a case history of a 46 year old male patient with successfully treated critical AS with severe heart failure (HF) that demonstrates effectiveness of the surgical treatment. Successful aortic valve replacement (AVR) was beneficial and guided to increase functional class, improve LV systolic function, normalization of the heart chambers, decreased pulmonary hypertension (PH), determined reversible left ventricle (LV) hypertrophy. Summarizing our experience, we hypothesize that surgical treatment of this patient with asymptomatic very severe AS would be helpful in increasing quality of life and avoiding manifestation of AS with critical severe HF.
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