Modern methods for identification and quantification of cardiac glycosides

Scientific relevance. Cardiac glycosides have been used in medicine for over two centuries. Current studies suggest that biologically active substances from this group can be used to treat not only heart conditions but also viral infections, cancers, and other diseases. Therefore, quality control methods for cardiac glycosides are becoming increasingly relevant.Aim. Based on a review of Russian and international quality standards, as well as up-to-date scientific data, this study aimed to identify promising methods for the identification and quantification of cardiac glycosides in herbal drugs and herbal medicinal products, as well as to evaluate the possibility of substituting physicochemical methods for biological methods.Discussion. The methods that are currently used to standardise cardiac glycosides are either not selective or require laboratory animals (biological test systems). According to a study of pharmacopoeial methods for the identification of cardiac glycosides in herbal drugs and herbal medicinal products, chemical identification tests and thin-layer chromatography continue to be relevant. Quantitative testing of herbal drugs and extracts uses biological and non-selective (spectrophotometry) methods, whereas chromatography is described only in general and individual monographs for herbal drug preparations containing individual cardiac glycosides and medicinal products containing these preparations. Upon analysing quality standards and scientific publications, the authors identified potentially promising methods for the quantification of cardiac glycosides in herbal drugs, herbal drug preparations, and herbal medicinal products, namely chromatographic methods.Conclusions. Reverse-phase high-performance liquid cjromatography (HPLC) with spectrophotometric detection is the most suitable method for pharmacopoeial analysis. The development of an HPLC-based analytical procedure to determine the cardiac glycoside content will provide an opportunity to advance from biological or non-selective methods to more ethical and selective up-to-date techniques

Myocardial revascularization in patients with acute coronary syndrome in the context of COVID-19 pandemic: a single-center prospective cohort study

Aim. To assess the outcomes of myocardial revascularization (MR) and identify risk factors for early postoperative complications in patients with coronary artery disease (CAD) with acute coronary syndrome (ACS) in the context of coronavirus disease 2019 (COVID-19) pandemic.Material and methods. The study included 769 patients aged 67,0±4,4 years with CAD with ACS in the period from April to October 2020. In an expedited manner, percutaneous transluminal coronary angioplasty (n=699) and on pump coronary artery bypass grafting (CABG) (n=70) were performed. All patients underwent a COVID-19 rapid tests. After MR, the following outcomes were recorded: adverse cardiovascular events and other complications; various surgical interventions; bilateral COVID-19 pneumonia; death. The follow-up period lasted 30 days.Results. During the hospitalization, COVID-19 was detected in 5,3% of patients (n=41). Among them, bilateral multisegmental pneumonia developed in 48,8%. Among infected patients, COVID-19-related mortality in the early postoperative period was 9,8%. The all-cause mortality rate was 0,7%. On pump CABG significantly increases the risk of developing COVID-19 pneumonia (odds ratio (OR), 23,2; 95% confidence interval (CI) 14,2-35,4; p<0,001). After MR, COVID-19 pneumonia was associated with respiratory (OR, 7,6; 95% CI, 4,3-11,5; p=0,001) and heart failure (OR, 4,2; 95% CI, 2,9-8,6; p=0,001), atrial fibrillation (OR, 8,3; 95% CI, 4,1-13,9; p=0,001), as well as with all-cause mortality (OR, 10,3; 95% CI, 5,2-16,7; p=0,005). Recurrent transmural myocardial infarction in patients with CAD was associated with heart failure after MR (OR, 7,1; 95% CI, 2,4-12,6; p=0,012).Conclusion. Conducting on pump CABG in patients with CAD with ACS is the leading trigger for developing COVID-19 pneumonia, which, during hospitalization after MR, was associated not only with respiratory complications, but also with impaired heart function, which significantly increases the death risk in this category of patients

Clinical and functional features and quality of life in depressive disorders in patients undergoing pulmonary thromboendarterectomy

Aim. To conduct a comparative analysis of clinical and functional parameters and quality of life (QoL) in patients with chronic thromboembolic pulmonary hypertension (CTEPH), depending on the presence of a depressive disorder in long-term postoperative period.Material and methods. The study included 182 patients with CTEPH in the long term after surgery. Depending on the Patient Health Questionnaire 9 ( PHQ-9) data, all patients were divided into 2 groups: the 1st group — patients without depressive syndrome in the long-term postoperative period, the 2nd — patients with depressive syndrome. A comparative assessment of the initial clinical and functional characteristics, as well as QoL was carried out using the SF-36 questionnaire in both groups of patients. In patients who had a coronavirus disease 2019 (COVID-19), a comparative assessment using the Post-COVID-19 Functional Status (PCFS) scale was carried out.Results. Clinically relevant depressive syndrome in patients with CTEPH in the long term after surgery was registered in 25,3% of cases. In the 2nd group of patients, prior myocardial infarction (p=0,02), concomitant chronic cerebrovascular disease (p=0,01), as well as moderate and severe post-COVID-19 functional limitations according to the PCFS scale (p=0,004) were significantly more often recorded compared with the 1st group. In the 2nd group of patients, the level of QoL in almost all parameters was significantly lower in comparison with the 1st group (p<0,05). Decreased QoL (score <40) in the 2nd group concerned numerous parameters, including the physical and mental health components. In the 1st group of patients, reduced QoL was observed only in some physical parameters.Conclusion. The group of patients with CTEPH with depressive syndrome in the long-term postoperative period was characterized by a higher incidence of concomitant chronic cerebrovascular disease and a history of myocardial infarction compared with patients without depressive disorders. In the group of patients with depressive disorders, moderate and severe post-COVID-19 functional limitations according to the PCFS scale were more often observed. Depressive disorders in patients with CTEPH in the long-term postoperative period were accompanied by significantly reduced QoL parameters. Patients experienced the greatest difficulties both during normal daily activities and in professional activities

Распространенность новой коронавирусной инфекции COVID-19 у пациентов, перенесших легочную эндартерэктомию (по данным одноцентрового регистра)

Aim. To assess the prevalence and clinical and functional features of a new coronavirus infection (COVID-19) in patients who underwent pulmonary thromboendarterectomy (PTE) using data from a single-center registry. Methods. This study included 127 patients with chronic thromboembolic pulmonary hypertension who underwent PTE from January 2016 to March 2020 and were included in a follow-up group. The follow-up after surgery was 6 or more months. The prevalence of COVID-19 and clinical and functional properties of the cardiorespiratory system were assessed in the study group. Results. The average follow-up period after PTE in the study group was 2.5 ± 0.9 years. 14 (11%) deaths not associated with COVID-19 were reported during this period. 5 cases of COVID-19 were detected among the remaining 113 patients. In one case, the infection was asymptomatic, while other patients had the typical clinical symptoms and developed bilateral polysegmental pneumonia. No patients required mechanical ventilation or died of COVID-19. All patients who underwent PTE were compliant with anticoagulation therapy and PAH-specific therapy for residual pulmonary hypertension. No adjustment of PAH-specific and anticoagulation therapy was required during COVID-19. Conclusion. The prevalence of COVID-19 in patients who underwent PTE was 4.4%, no deaths were recorded. Outpatient follow-up and timely informing of patients undergoing PTE allow keeping the COVID-19 morbidity and mortality in the studied group at the general population level. Evaluation of the impact of chronic anticoagulants and PAH-specific therapy on the outcome of COVID-19 deserves further research.Целью исследования явилась оценка распространенности и клинико-функциональных особенностей новой коронавирусной инфекции (COVID-19) у пациентов, перенесших легочную эндартерэктомию (ЛЭЭ), на примере одноцентрового регистра. Материал и методы. В исследование включены пациенты (n = 127) с хронической тромбоэмболической легочной гипертензией, перенесшие в период с января 2016 по март 2020 г. ЛЭЭ и состоявшие в группе диспансерного наблюдения. Срок наблюдения после хирургического вмешательства составил ≥ 6 мес. Проведена оценка распространенности COVID-19 и клинико-функциональных особенностей кардиореспираторной системы у обследованных пациентов. Результаты. Средний срок наблюдения после ЛЭЭ составил 2,5 ± 0,9 года. Летальность, не ассоциированная с COVID-19, за этот период составила 14 (11 %) случаев, среди остальных пациентов (n = 113) выявлено 5 случаев COVID-19. В 1 случае течение инфекционного заболевания было бессимптомным, в остальных – с типичной клинической симптоматикой и развитием двусторонней полисегментарной пневмонии. Случаев, при которых потребовалась искусственная вентиляция легких, и летальных исходов не зарегистрировано. Все пациенты, перенесшие ЛЭЭ, соблюдали рекомендации по приему антикоагулянтов и при наличии резидуальной легочной гипертензии получали специфическую терапию. Во время лечения COVID-19 коррекция терапии не требовалась. Заключение. Заболеваемость COVID-19 в группе пациентов, перенесших ЛЭЭ, составила 4,4 %, летальных исходов не зарегистрировано. При диспансерном наблюдении и своевременном информировании пациентов, перенесших ЛЭЭ, уровень заболеваемости и смертности от COVID-19 может не превышать таковой в общей популяции. Требуются дальнейшее изучение и оценка влияния на клиническую картину и исход COVID-19 при постоянном приеме антикоагулянтов и специфических препаратов для лечения легочной артериальной гипертензии

ОСОБЕННОСТИ МИКРОЦИРКУЛЯТОРНОГО КРОВОТОКА КАМЕР СЕРДЦА ДО И ПОСЛЕ ОПЕРАЦИИ У ПАЦИЕНТОВ С АОРТАЛЬНЫМ СТЕНОЗОМ В СОЧЕТАНИИ С ИШЕМИЧЕСКОЙ БОЛЕЗНЬЮ СЕРДЦА

Purpose. Evaluate the level of MBF in the walls of the heart chambers in elderly patients with AS and no coronary heart disease as well as with coronary heart disease before and after surgery.Materials and methods. We examined intraoperative microcirculatory blood flow (MBF) in the different heart chambers by laser doppler flowmetry in 36 patients over 60 years of age with aortic stenosis (AS), as well as with AS and coronary heart disease (CHD). MBF was assessed using laser-Doppler flowmetry (LDF) in milliliters per100 gtissue per minute.Results. Before surgery patients with AS and coronary artery disease had the lowest MBF volume rate in the wall of the left ventricle compared with patients with AS and no coronary artery disease. Patients with AS and coronary artery disease demonstrated the most pronounced gradient of the microcirculation level before and after surgery: from the lowest blood fl ow in the left atrium (below 60 mL/100g/ min) to the highest in the right ventricle (above 75 mL/100g/min).Conclusion. MBF in the walls of the heart chambers in patients with AS and CAD is characterized by the lowest volume of blood flow velocity in the wall of the left ventricle compared with patients with AS and no concomitant coronary heart disease. Цель. Оценить уровень микроциркуляторного кровотока (МЦК) в стенках камер сердца у пациентов пожилого возраста с аортальным стенозом без ИБС и на фоне атеросклеротического поражения коронарных артерий до и после хирургического лечения.Материалы и методы. МЦК различных камер сердца исследовался интраоперационно у 36 пациентов старше 60 лет с аортальным стенозом (АС), а также с АС в сочетании с ишемической болезнью сердца (ИБС). МЦК исследовался с помощью метода лазер-допплеровской флоуметрии (ЛДФ) в мл на100 гткани в мин.Результаты. До операции у пациентов с АС и ИБС выявлена наиболее низкая объемная скорость МЦК в стенке левого желудочка по сравнению с пациентами с АС без ИБС. У больных АС в сочетании с ИБС до и после операции отмечен наиболее выраженный градиент уровня микроциркуляции от наиболее низкого кровотока по левому предсердию (ниже 60 мл/100г/мин) до наиболее высокого по правому желудочку (выше 75 мл/100г/мин).Заключение. МЦК в стенках камер сердца у пациентов с АС на фоне атеросклеротического поражения коронарного русла характеризуется наиболее низкой объемной скоростью кровотока в стенке левого желудочка по сравнению с пациентами с АС без сопутствующей ИБС.

Хроническая обструктивная болезнь легких и результаты реваскуляризации миокарда: взаимосвязь с качеством жизни

Aim. To assess the impact of chronic obstructive pulmonary disease (COPD) on the outcomes of myocardial revascularisation and the self-reported quality of life (QoL) during long-term follow-up. Methods. This prospective cohort study included 454 consecutive patients who underwent scheduled myocardial revascularisation. The follow-up continued for 3 years after the surgery. All patients underwent pulmonary functional tests before the surgery. The diagnosis of COPD was verified according to the Global Initiative for Obstructive Lung Disease criteria. QoL assessment was performed before and 3 years after the surgery using the 36-Item Short-Form Health Survey (SF-36). Results. In the study group, the diagnosis of COPD was verified in 14.5% of cases. The mortality rate was 5%, and was significantly higher in patients with COPD. The baseline QoL level was reduced in all patients, regardless of the presence of COPD, with an average of 50 points both in the physical and mental health scores of the SF-36 questionnaire. COPD had a significant negative impact on the QoL physical health score after myocardial revascularisation (odds ratio (OR) 0.95 (0.91 - 0.99), p = 0.043). The forced expiratory volume in the first second (OR 1.02 (1.00 - 1.07), p = 0.048) and new-onset atrial fibrillation in the early postoperative period (OR 0.54 (0.33 - 0.88), p = 0,036) were predictors of lack of QoL improvement. COPD did not correlate with the changes in the psychoemotional component of QoL. Conclusion. COPD has an independent negative impact on the clinical outcomes of myocardial revascularisation, including survival and health-related QoL (physical health score). Thereby, preoperative assessment of the respiratory function is important in these patients.Целью исследования явилась оценка влияния хронической обструктивной болезни легких (ХОБЛ) на результаты реваскуляризации миокарда (РМ) и качество жизни (КЖ) пациентов в долгосрочном периоде наблюдения. Материалы и методы. В проспективное когортное исследование включены пациенты (n = 454) с ишемической болезнью сердца, госпитализированные для проведения плановой РМ. Период наблюдения составил 3 года после вмешательства. До хирургического лечения у пациентов проводились легочные функциональные тесты. Диагноз ХОБЛ верифицирован в соответствии с критериями Глобальной инициативы диагностики лечения и профилактики ХОБЛ (Global Initiative for Chronic Obstructive Lung Disease (GOLD)). Оценка КЖ проводилась до и через 3 года после хирургического вмешательства по данным опросника SF-36. Результаты. Диагноз ХОБЛ верифицирован в 14,5 % случаев. Смертность при 3-летнем наблюдении после РМ составила 5 % со значительным преобладанием среди пациентов с ХОБЛ. Независимо от наличия ХОБЛ, исходно сниженный уровень КЖ отмечен у всех кардиохирургических пациентов по шкале SF-36 (физический и психоэмоциональный компоненты КЖ). Установлено значимое негативное влияние ХОБЛ на динамику КЖ после РМ по шкале физического компонента КЖ (отношение шансов (ОШ) — 0,95 (0,91—0,99); р = 0,043). Предикторами отсутствия положительной динамики КЖ также явились такие показатели, как объем форсированного выдоха за 1-ю секунду (ОШ — 1,02 (1,00—1,07); р = 0,048) и впервые возникшая в раннем послеоперационном периоде фибрилляция предсердий (ОШ - 0,54 (0,33-0,88); р = 0,036). В данном исследовании не показано значимой связи ХОБЛ с динамикой психоэмоционального компонента КЖ. Заключение. У пациентов, перенесших РМ, ХОБЛ оказывает независимое негативное влияние на клинический исход, включая выживаемость и КЖ (физический компонент здоровья), при этом подчеркивается важность предоперационной оценки функции внешнего дыхания у пациентов кардиохирургического профиля

НАРУШЕНИЯ ФУНКЦИИ ВНЕШНЕГО ДЫХАНИЯ И ИХ ВЛИЯНИЕ НА КЛИНИЧЕСКИЙ ИСХОД У КАРДИОХИРУРГИЧЕСКИХ ПАЦИЕНТОВ

Goal: to investigate the frequency and specific features of respiratory disorders and their impact on the clinical course in the patients having coronary artery bypass graft operation. Materials. 454 patients expecting coronary artery bypass graft operation were enrolled into the prospective cohort study. External respiration function was evaluated prior to the surgery. Pathologic respiration patterns were assessed basing on forced expiratory volume per 1 second (FEV1 ) and forced vital lung capacity (FVLC). The pattern was evaluated as obstructive with the ratio of FEV1 /FVLC < 0.70; and the restrictive pattern was the combination of FEV1 /FVLC≥ 0.70 and FVLC < 80% of "must". Results. Obstructive and restrictive patterns were detected in 72 (15.8%) and 50 (11.0%) patients respectively. Out of 133 patients with compromised external respiration function chronic obstructive pulmonary disease was diagnosed only in 26 patients. Bronchial obstruction was related to the risk of auricular fibrillation, increase of duration of artificial pulmonary ventilation and prolonged hospital stay. Conclusion. It has been demonstrated that it is possible to improve clinical outcomes in the patients undergoing cardiac surgery through diagnostics of respiratory disorders, detection of risk groups and prevention of complications. Цель: изучить встречаемость и характеристики респираторных нарушений и их влияния на клиническое течение у пациентов при операциях коронарного шунтирования. Материал. В проспективное когортное исследование было включено 454 пациента, которым планировалось коронарное шунтирование. Оценку функции внешнего дыхания выполняли перед операцией. Патологический респираторный паттерн определяли на основании объема форсированного выдоха в 1-ю секунду (ОФВ1 ) и форсированной жизненной емкости легких (ФЖЕЛ). Критерием обструктивного паттерна являлось соотношение ОФВ1 /ФЖЕЛ < 0,70, рестриктивного − комбинация ОФВ1 /ФЖЕЛ ≥ 0,70 и ФЖЕЛ < 80% от «должного». Результаты. Обструктивный и рестриктивный паттерны были выявлены у 72 (15,8%) и 50 (11,0%) пациентов соответственно. Из 133 пациентов со снижением функции внешнего дыхания только 26 имели диагноз хронической обструктивной болезни легких. Бронхиальная обструкция была связана с риском развития фибрилляции предсердий, увеличением длительности искусственной вентиляции легких и срока госпитализации. Вывод. Продемонстрирована возможность улучшения клинических исходов у кардиохирургических пациентов путем диагностики респираторных нарушений, выявления групп риска и профилактики осложнений.

ВПЛИВ РІЗНИХ ФАКТОРІВ НА ВТРАТИ ЕЛЕКТРИЧНОЇ ЕНЕРГІЇ В ТЯГОВІЙ МЕРЕЖІ ПРИ РОБОТІ ЕЛЕКТРОВОЗІВ ЗМІННОГО СТРУМУ

The article is devoted to the impact of the drawbacks of the existing a.c. power supply system on the energy losses in catenary, and to the imperfections of electric energy accounting system.Рассмотрено влияние недостатков тяговой системы электроснабжения переменного тока на потери электрической энергии в тяговой сети, а также несовершенство системы учета электрической энергии.Розглянуто вплив недоліків тягової системи електропостачання змінного струму на втрати електричної енергії в тяговій мережі, а також недосконалість системи обліку електричної енергії

INELASTIC LIGHT SCATTERING BY MAGNONS IN ANTIFERROMAGNETIC EuTe

One-magnon inelastic light scattering in EuTe by thermal magnons belonging to both branches of the excitation spectrum is studied. The dependences of the magnon frequency and of the intensity of the scattered light on the magnetic field are measured. The contribution to the intensity of one-magnon light scattering from exchange mechanism, which is of decisive importance for strongly canted magnetic sublattices, is separated

Vascular channel reserves in patients with systemic atherosclerosis and type 2 diabetes mellitus

Aims. To determine vascular channel reserves in patients with systemic atherosclerosis and type 2 diabetes mellitus (T2DM). Materials and Methods. Study included 143 patients with systemic atherosclerosis, 40 of them also suffered from T2DM. We applied laser Doppler flowmetry (LDF) to evaluate vascular channel reserves and transcranial spectrometry to assess cerebral oxygenation status. Results. We found that 60% of patients with systemic atherosclerosis and T2DM show microcirculation parameters below critical level, which indicates failure of collateral circulation. This group also showed lower efficiency of cerebral perfusion and more pronounced vascular constriction in response to functional load as compared to diabetes-negative controls. Conclusion. Patients with T2DM, accompanied with systemic atherosclerosis showed lower circulation efficiency and more pronounced autonomous dysregulation of cerebral circulation against patients without diabetes mellitus