Effects of guanidine on synaptic transmission in the spinal cord of the frog

The effects of guanidine on motoneurons of the isolated frog spinal cord were studied by adding the drug to the solution bathing the cord during intracellular recording. Guanidine (5·10–4 M) did not alter the membrane potential of motoneurons. The main effect was a marked increase of the amplitudes and frequencies of small spontaneously occurring inhibitory postsynaptic potentials. The hyperpolarizing component of postsynaptic potentials evoked by stimulation of dorsal roots was also enhanced by guanidine. Higher concentrations of guanidine (5·10–3 M) resulted in a very large and irreversible increase of the small spontaneously occurring inhibitory potentials, which now appeared in a regular, rhythmic pattern. The effects of guanidine could easily be blocked by increasing the magnesium ions (15 mM) in the bath solution. These results indicate that guanidine facilitates the release of an inhibitory transmitter in afferent terminals of the frog spinal cord either by a direct action on these terminals or indirectly by an action on nerve endings impinging on inhibitory interneurons

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

Функциональное состояние кардиореспираторной системы после ортотопической трансплантации сердца с длительной холодовой ишемией трансплантата

Objective: to assess the functional state of the cardiorespiratory system in the long term after orthotopic heart transplantation (HT) with prolonged cold ischemia time. Materials and methods. The results of 60 orthotopic HTs performed at Meshalkin National Medical Research Center were analyzed. A comparison was made of the immediate and long-term outcomes of HTs in the group with cold ischemia time lasting for less than 240 minutes and in those with farther distance between donor and recipient sites with cold ischemia time of 240 minutes or more. In the long-term follow-up after HT, all patients underwent cardiopulmonary exercise testing, body plethysmography, assessment of the diffusing capacity of the lungs, and quality of life assessment. Results. Prolonged cold ischemia showed a negative effect on the early postoperative period – decreased myocardial contractility on postoperative day 1 and longer duration of inotropic support. At the same time, the survival rate and incidence of graft rejection reactions in the early and late post-HT periods in the studied groups did not differ significantly. Peak oxygen consumption in the general group in the long term after HT was 17 (14.7–21.0) mL/kg/min, VE/ VCO2 slope was 30 (29–36) at 100 (90–120) W threshold load power. All the parameters of pulmonary function tests did not differ significantly depending on cold ischemia duration. Quality of life also did not show significant differences depending on the duration of graft ischemia in terms of both physical and psycho-emotional health components of the SF-36 questionnaire. Conclusion. Long-term cold ischemia of the graft did not show any negative impact on the functional state of the cardiorespiratory system and quality of life in the long term after HT. The studied group of recipients was characterized by high efficiency of pulmonary ventilation and gas exchange, as well as high tolerance to physical activity in the long-term post-HT period.Цель. Оценка функционального состояния кардиореспираторной системы в отдаленные сроки после ортотопической трансплантации сердца (ТС) с длительной холодовой ишемией трансплантата. Материалы и методы. Проанализированы результаты 60 ортотопических ТС, выполненных в ФГБУ «НМИЦ им. акад. Е.Н. Мешалкина» Минздрава России. Проведено сравнение непосредственных и отдаленных результатов ТС в группах с холодовой ишемией трансплантата менее 240 минут и при дистанционном изъятии с холодовой ишемией 240 минут и более. В отдаленные сроки после ТС всем пациентам проведено кардиопульмональное нагрузочное тестирование, бодиплетизмография, оценка диффузионной способности легких, оценка качества жизни. Результаты. Длительная холодовая ишемия донорского сердца показала негативное влияние на ранний послеоперационный период ТС в виде снижения сократительной способности миокарда в первые сутки после операции и увеличения длительности инотропной поддержки. При этом выживаемость и частота развития реакций отторжения трансплантата в ранние и отдаленные сроки после ТС в изучаемых группах значимо не различалась. Пиковое потребление кислорода в отдаленные сроки после ТС в общей группе составило 17 (14,7–21,0) мл/мин/кг, VE/VCO2 slope – 30 (29–36) при пороговой мощности нагрузки 100 (90–120) Вт. Все параметры легочных функциональных тестов не имели значимых отличий в зависимости от длительности холодовой ишемии. Качество жизни также не показало значимых различий в зависимости от длительности ишемии трансплантата как по физическому, так и психоэмоциональному компонентам здоровья опросника SF-36. Заключение. Длительная холодовая ишемия трансплантата не показала отрицательного влияния на функциональное состояние кардиореспираторной системы и качество жизни в отдаленные сроки после ТС. Изучаемая группа реципиентов характеризовалась высокой эффективностью легочной вентиляции и газообмена, а также высокой толерантностью к физическим нагрузкам в отдаленные сроки после ТС

Хроническая обструктивная болезнь легких как предиктор неблагоприятного прогноза хирургического лечения хронической тромбоэмболической легочной гипертензии

Aim. The aim of this study was to investigate an influence of pulmonary ventilation and diffusion disorders on outcome of pulmonary endarterectomy.Methods. The study involved patients with chronic thromboembolic pulmonary hypertension (CTEPH) with (n = 43) or without (n = 88) chronic obstructive pulmonary disease (COPD). Body plethysmography and lung diffusing capacity measurement were performed in all patients before pulmonary endarterectomy. We analyzed perioperative clinical characteristics, complications and inhospital mortality.Results. COPD was diagnosed twice more often in patients with CTEPH. Patients with CTEPH and COPD had more severe lung function disorders including more significant reduction in lung diffusing capacity. Comorbidity of COPD and CTEPH significantly increased a risk of respiratory failure in early postoperative period (OR = 2.1 (1.25 – 4.76), p = 0.020), length of hospitalization (p = 0.02), and a risk of inhospital mortality (OR = 4.4 (1.21 – 16.19), p = 0.023). Lung diffusion capacity had an independent predictive value to predict the development of the respiratory failure in early postoperative period (OR = 1.8 (1.08 – 3.57), p = 0.050).Conclusion. Diagnosis of COPD in patients with CTEPH significantly increased risk of poor outcome of the pulmonary endarterectomyЦель. Оценка влияния вентиляционных и диффузионных нарушений функции внешнего дыхания (ФВД) на результаты тромбэндартерэктомии (ТЭЭ) из ветвей легочной артерии (ЛА).Материалы и методы. В исследование включены пациенты с хронической тромбоэмболической легочной гипертензией (ХТЭЛГ), разделенные затем на 2 группы в зависимости от наличия (1я группа; n = 43) или отсутствия (2я группа; n = 88) сопутствующей хронической обструктивной болезни легких (ХОБЛ). Всем пациентам выполнены бодиплетизмография и оценка диффузионной способности легких (DLCO) за 1 сутки до предполагаемого хирургического вмешательства в объеме ТЭЭ из ветвей ЛА. Анализировались клинические периоперационные характеристики, осложнения и госпитальная летальность пациентов.Результаты. Установлено, что частота встречаемости ХОБЛ в исследуемой группе пациентов с ХТЭЛГ практически в 2 раза превышает частоту наличия диагноза ХОБЛ в анамнезе. По результатам функциональных легочных тестов закономерно показаны более выраженные нарушения ФВД у пациентов с ХТЭЛГ с сопутствующей ХОБЛ, включая более выраженное снижение DLCO. При наличии ХОБЛ у пациентов с ХТЭЛГ достоверно повышаются риск возникновения дыхательной недостаточности (ДН) в раннем послеоперационном периоде (отношение шансов (ОШ) – 2,1 (1,25–4,76); p = 0,020), длительность госпитализации (p = 0,02) и риск госпитальной летальности (ОШ – 4,4 (1,21–16,19); p = 0,023). При анализе DLCO показана независимая предикторная ценность в отношении риска развития ДН в раннем послеоперационном периоде (ОШ – 1,8 (1,08–3,57); p = 0,050).Заключение. При ХОБЛ у пациентов с ХТЭЛГ значительно увеличивается риск неблагоприятного исхода ТЭЭ из ветвей ЛА

Insights into the abundance and diversity of abyssal megafauna in a polymetallic-nodule region in the eastern Clarion-Clipperton Zone

There is growing interest in mining polymetallic nodules in the abyssal Clarion-Clipperton Zone (CCZ) in the Pacific. Nonetheless, benthic communities in this region remain poorly known. The ABYSSLINE Project is conducting benthic biological baseline surveys for the UK Seabed Resources Ltd. exploration contract area (UK-1) in the CCZ. Using a Remotely Operated Vehicle, we surveyed megafauna at four sites within a 900 km2 stratum in the UK-1 contract area, and at a site ~250 km east of the UK-1 area, allowing us to make the first estimates of abundance and diversity. We distinguished 170 morphotypes within the UK-1 contract area but species-richness estimators suggest this could be as high as 229. Megafaunal abundance averaged 1.48 ind. m−2. Seven of 12 collected metazoan species were new to science, and four belonged to new genera. Approximately half of the morphotypes occurred only on polymetallic nodules. There were weak, but statistically significant, positive correlations between megafaunal and nodule abundance. Eastern-CCZ megafaunal diversity is high relative to two abyssal datasets from other regions, however comparisons with CCZ and DISCOL datasets are problematic given the lack of standardised methods and taxonomy. We postulate that CCZ megafaunal diversity is driven in part by habitat heterogeneity.This open access work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0

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

Паттерн элиминации углекислого газа при кардиопульмональном нагрузочном тестировании у пациентов с низким показателем сердечного выброса

The objective of this study was to evaluate partial pressure of end tidal carbon dioxide (PetCO2) over time on exertion (E) and its predictive value in evaluation of risk of unfavorable outcome in patients with low ejection fraction (EF) value.Materials and Methods. Patients (n = 53) with pronounced chronic heart failure (CHF), included in heart transplantation waiting list, were enrolled in the prospective study. All patients underwent cardiopulmonary exercise testing (CPET). Mortality or INCOR left ventricle bypass system implantation according to vital indications within 1 year of follow-up were evaluated as an end-point.Results. Patients with CHF and low EF were characterized by low parameters of E tolerance and peak oxygen consumption (10.4 (9.6–11.7) ml/min/kg). The average PetCO2 level by group was 30.4 (28.3–33.0) mm Hg; in 32% of patients this value decreased or did not change in CPET compared with that in resting state. The significant relationship between increased risk of unfavorable outcome within 1 year of follow-up with low baseline PetCO2 value (odds ratio (OR) – 0.22 (0.05–0.87); p = 0.020) and absence of its increment in PE (OR – 0.16 (0.10–0.54); p = 0.009) was observed.Conclusion. The significant predictive factors of unfavorable outcome within 1 year of follow-up in patients with pronounced CHF and low EF include PetCO2 value in resting state, as well as PetCO2 change over time after E challenge.Целью данной работы явилась оценка динамики парциального давления углекислого газа в конечной порции выдоха (PetCO2) при физической нагрузке (ФН) и ее прогностической значимости при оценке риска неблагоприятного исхода у пациентов с низким показателем сердечного выброса (СВ).Материал и методы. В проспективном исследовании приняли участие пациенты (n = 53) с выраженной хронической сердечной недостаточностью (ХСН), включенные в лист ожидания трансплантации сердца. Всем больным проведено кардиопульмональное нагрузочное тестирование (КПНТ). В качестве конечной точки наблюдения оценивались летальность или установка системы обхода левого желудочка INCOR по жизненным показаниям в течение 1 года наблюдения.Результаты. Пациенты с ХСН и низким СВ характеризовались низкими показателями толерантности к ФН и пикового потребления кислорода (10,4 (9,6–11,7) мл / мин / кг). Уровень PetCO2 в среднем по группе составил 30,4 (28,3–33,0) мм рт. ст., у 32 % пациентов данный показатель снижался или не менялся при выполнении КПНТ по сравнению с таковым в состоянии покоя. Показана значимая взаимосвязь повышения риска неблагоприятного исхода в течение 1 года наблюдения с низким исходным значением PetCO2 (отношение шансов (ОШ) – 0,22 (0,05–0,87); p = 0,020) и отсутствием его прироста при ФН (ОШ – 0,16 (0,10–0,54); p = 0,009).Заключение. Значимыми прогностическими факторами неблагоприятного исхода в течение 1 года наблюдения у пациентов с выраженной ХСН и низким СВ являются значение PetCO2 в покое, а также динамика PetCO2 при провокации ФН

Automatic Prediction of Facial Trait Judgments: Appearance vs. Structural Models

Evaluating other individuals with respect to personality characteristics plays a crucial role in human relations and it is the focus of attention for research in diverse fields such as psychology and interactive computer systems. In psychology, face perception has been recognized as a key component of this evaluation system. Multiple studies suggest that observers use face information to infer personality characteristics. Interactive computer systems are trying to take advantage of these findings and apply them to increase the natural aspect of interaction and to improve the performance of interactive computer systems. Here, we experimentally test whether the automatic prediction of facial trait judgments (e.g. dominance) can be made by using the full appearance information of the face and whether a reduced representation of its structure is sufficient. We evaluate two separate approaches: a holistic representation model using the facial appearance information and a structural model constructed from the relations among facial salient points. State of the art machine learning methods are applied to a) derive a facial trait judgment model from training data and b) predict a facial trait value for any face. Furthermore, we address the issue of whether there are specific structural relations among facial points that predict perception of facial traits. Experimental results over a set of labeled data (9 different trait evaluations) and classification rules (4 rules) suggest that a) prediction of perception of facial traits is learnable by both holistic and structural approaches; b) the most reliable prediction of facial trait judgments is obtained by certain type of holistic descriptions of the face appearance; and c) for some traits such as attractiveness and extroversion, there are relationships between specific structural features and social perceptions