NCT02137187 (May 2018, date last accessed).
The results of the study of the efficiency of heat treatment of samples of glauconite are presented. Estimated ability of the sorbent to water absorption and retention of petroleum products. It was established by the method of differential scanning calorimetry that thermally activated glauconite samples are practically not saturated with water vapor. Oil capacity decreases after heat treatment of glauconite at 600°C and increases at 1000°C compared with the original sample, which is explained by various structural changes.
<p><strong>Background.</strong> Cardiac resynchronisation therapy (CRT) has been used for the treatment of patients with congestive heart failure (CHF) and wide QRS complexes for more than ten years. Nevertheless, the percentage of patients unresponsive to this therapy is 30%. There is recent evidence for increased responder proportions to treatments with multipolar pacing of the left ventricle (LV) in CRT. Accordingly, the aim of this study is to evaluate the effectiveness of multi-polar pacing of LV in patients with CHF and indications for CRT.</p><p><strong>Methods.</strong> Sixty-two patients [42 men, mean age 62.5 (58–68) years] with CHF and indications for CRT (for example patients with symptomatic heart failure and QRS duration ≥130 ms with left bundle branch block and left ventricular ejection fraction ≤ 35%) were included in this prospective, pilot, randomised study. Patients were implanted with cardiac resynchronisation devices with multi-polar electrodes. After implantation, patients were randomised into two groups according to the programming of the LV stimulation vector: true bipolar stimulation (group 1, stimulation vector LVring-LVtip, n = 31) and extended-bipolar LV stimulation (group 2, standard programming LV ring to RV, n = 31). The main objective of the study was to assess the effects of true bipolar stimulation on the increase of the number of CRT responders. Responders were defined as patients with a 15% decrease in the left ventricular end systolic volume compared with the initial characteristics as detected by echocardiography. Secondary points included changes in a) left ventricular ejection fraction (LVEF), b) 6-min walk test dynamics, and c) brain natriuretic peptide. The observation period was 12 months.</p><p><strong>Results.</strong> The LV electrode was implanted in the anterior (6%), antero-lateral (8%), lateral (18%), posterior (2%), or postero-lateral (66%) branches of the coronary sinus, and the average LV stimulation threshold was 1.7 ± 1.1 V. No intra-operative complications were detected. Four patients (6.5%) underwent LV electrode re-positioning on the second day after surgery owing to diaphragmatic nerve stimulation. At the end of the observation period, the average threshold used for LV stimulation of patients in the true bi-polar stimulation group with the LVring-LVtip vector was 1.9 ± 1.5 V compared with 1.6 ± 1.3 V in the case of the extended-bipolar LV stimulation group (p = 0.88). The number of responders in the true bipolar stimulation group was 25 (80.6%) compared with 21 (67.7%) patients in the extended-bipolar LV stimulation group (p = 0.38). LVEF significantly increased in both groups compared with pre-operative values without significant differences between the groups (29.4 vs. 36.5, p < 0.001 in the extended bipolar LV stimulation group; 28.0 vs. 34.9, p < 0.001 in the true bi-polar stimulation group, p = 0.86 between groups). The distance covered during the 6-min walk test significantly increased in both groups compared with pre-operative values in the absence of a significant difference between the groups (p = 0.92). The decreased levels of the cerebral natriuretic peptide were 60.3 ± 42.3 pg/ml and 56.6 ± 38.5 pg/ml in the extended and true bipolar stimulation groups, respectively (p = 0.95). </p><p><strong>Conclusion.</strong> Based on the results of this pilot study, the choice of a vector for true bipolar LV stimulation demonstrated its advantage and tendency to increase the number of responders in subjects with implanted CRT devices. Subsequent multi-centre randomised trials will help determine the role of true bipolar LV stimulation and extended-bipolar stimulation from different regions of the LV to increase the response to CRT.</p><p><br />Received 24 December 2019. Revised 18 January 2020. Accepted 20 January 2020.</p><p><strong>Funding:</strong> The work is supported by a grant of the President of the Russian Federation No. МД-2893.2018.7.</p><p><strong>Conflict of interest:</strong> Authors declare no conflict of interest.</p><p><strong>Author contributions</strong><br />Conception and study design: A.B. Romanov<br />Data collection and analysis: A.V. Ponomarenko, I.L. Mikheenko, E.A. Morzhanayev, A.G. Filippenko, R.E. Zhizhov, I.S. Peregudov<br />Statistical analysis: A.B. Romanov, I.L. Mikheenko<br />Drafting the article: A.V. Ponomarenko, I.L. Mikheenko, E.A. Morzhanayev<br />Critical revision of the article: A.B. Romanov, D.V. Losik, I.L. Mikheenko, A.V. Ponomarenko, V.V. Shabanov, S.N. Artemenko <br />Final approval of the version to be published: A.V. Ponomarenko, I.L. Mikheenko, E.A. Morzhanayev, A.G. Filippenko, D.V. Losik, V.V. Shabanov, I.S. Peregudov, R.E. Zhizhov, A.B. Romanov, S.N. Artemenko</p>
In the electroplating industry, large volumes of water are used, which are polluted at various stages in the process. Waste water containing transition metal ions is not only a dangerous source of environmental pollution, but also valuable waste. Taking into account the problems associated with the ecology and the rational use of natural resources, it is necessary to create low- and non-waste production, in particular, to develop new technological processes and appropriate equipment, to introduce water-circulation cycles. This paper presents the results of a study of the sorption of copper (II) and nickel (II) cations by the FIBAN X-1 ion exchange fiber. Calorimetric studies of the thermal effects of the interaction of FIBAN X-1 fiber with solutions of copper (II) and nickel (II) nitrates were carried out. It is shown that the power, thermal effect and time of the process depend on the nature and concentration of metal ions in the solution. Based on the experimental data, the enthalpy of the process was calculated. The endothermic effect of the process is explained by the energy costs associated with dehydration effects and changes in the conformation of the polymer fiber chains. Sorption isotherms of these ions were obtained. It has been established that at all concentrations studied, Ni2 + ions under these conditions are absorbed by ion exchange fibers better than Cu2 + cations. The calculated sorption constants for copper (II) and nickel (II) are greater than 1. It is shown that the Langmuir equation describes the sorption isotherm better than the Freundlich equation. For deep purification of waste water from metal ions, it was proposed to use the fibrous sorbent FIBAN X-1.
<p>Access to the left atrium during transseptal puncture for radiofrequency ablation in patients with atrial fibrillation (AF) and implanted atrial septal occluder can be challenging. This is particularly true when the occluder covers the entire septum and there is no ideal puncture site. This might lead to potential difficulties in arrhythmia treatment.<br />A 59-year-old patient with drug refractory AF, a dilated left atrium, and an implanted atrial septal occluder underwent double transseptal puncture through atrial septal occluder with subsequent pulmonary vein isolation using remote magnetic navigation. The effectiveness of the manipulation was confirmed by intraoperative stimulation from the Lasso catheter and by Holter monitoring data post-operation. It was revealed that the patient had sinus rhythm and no complications occurred. There were no shunts at the occluder level on transthoracic echocardiography, and there were no atrial tachyarrhythmias during the nine-month follow up period without antiarrhythmic drugs. The presented clinical case demonstrates the safety and efficacy of transseptal puncture through an implanted occluder in the interatrial septum to perform re-ablation using robotic magnetic navigation in a patient with AF.</p><p>Received 21 October 2020. Revised 20 November 2020. Accepted 25 November 2020.</p><p><strong>Funding:</strong> The work is supported by a grant of the President of the Russian Federation No. МД-1997.2020.7.</p><p><strong>Conflict of interest:</strong> Authors declare no conflict of interest.</p><p><strong>Author contributions</strong> <br />Drafting the article: А.V. Ponomarenko, R.E. Zhizhov, V.V. Baranova, E.V. Fisher, A.B. Romanov<br />Literature review: А.V. Ponomarenko, R.E. Zhizhov, V.V. Baranova, E.V. Fisher<br />Illustrations: А.V. Ponomarenko, A.B. Romanov<br />Critical revision of the article: А.V. Ponomarenko, R.E. Zhizhov, V.V. Baranova, A.M. Chernyavskiy, A.B. Romanov<br />Surgical treatment: N.А. Yelemessov, I.S. Peregudov, V.V. Shabanov, A.B. Romanov<br />Final approval of the version to be published: А.V. Ponomarenko, N.А. Yelemessov, I.S. Peregudov, R.E. Zhizhov, V.V. Baranova, E.V. Fisher, V.V. Shabanov, A.M. Chernyavskiy, A.B. Romanov</p>
The task of isolating and separating amino acids from aqueous solutions exists in various industries. The traditional method of isolation is ligand exchange chromatography. When choosing a cation for ligand-binding chromatography based on its binding strength with the ion exchanger, often used as a sulfonated polystyrene ion exchanger keeps the copper (II) firmly enough, and therefore, it is easily replaced by other cations. Chelating ion exchangers charge cations of copper (II), which hold these ions firmly enough. In this case, separating a mixture of substances, it is due to differences in the constants of complexation agents and complexes distribution coefficients. The study of the interaction of amino acids with the aliphatic carboxylic acid, the exchange of phosphoric acid cations and the amino carboxylic and amino phosphonic polyampholytes has shown a significant effect of the pH of the medium on the nature of the sorption equilibria. Under certain conditions, in the phase of the ion exchanger in the form of complexing metal cations, the formation of new sorption centers is possible, which occur upon sorption of amino acids in the formation of mixed ligand compounds: the sorbent complex may simultaneously comprise amino acids and attached functional groups of the sorbent as ligands. The influence of the hydrogen index of the medium primarily affects the change in the nature of the formed complex compounds in the sorbent phase and the equilibrium solution and the ratio of their stability constants. If the stability constant of the ion exchanger complex is higher than the stability constant of the compound with a low molecular weight ligand, then the sorbed copper cations interact with incoming methionine ions without breaking the metal – functional group of the ion exchanger coordination bond. If the ratio of stability constants is the opposite, then the predominant elution of copper (II) cations occurs with the formation of complex compounds with an amino acid in an aqueous solution.
<p>Despite the development of modern diagnostic technology and intraoperative navigation, catheter ablation of ventricular tachycardia in patients with coronary heart disease remains difficult. This procedure is challenging because of the electrical heterogeneity of the damaged myocardium, which leads to the emergence of reentry cycles. The clinical case that is presented is part of a study aimed at finding a personalized approach to VT ablation.<br />A 53 year old man with coronary heart disease, post-infarction cardiosclerosis, stenting of the right coronary artery and paroxysmal ventricular tachycardia was admitted to the cardiac surgery department with arrhythmias. Recently, this patient had experienced paroxysms of arrhythmias more frequently, up to several times a month, despite receiving antiarrhythmic therapy. Upon admission, the patient complained of a rapid heartbeat, weakness and discomfort in the chest area. The patient’s current drug therapy included betalok, cardiomagnyl and rosuvastatin. Due to his condition, the patient was asked to participate in a study with the aim of developing a personalized approach to the ablation of ventricular cardiac arrhythmias.<br />After the patient agreed to be included in the study, he underwent a series of tests including single-photon emission computed tomography of the myocardium with perfusion and non-neutropic radiopharmaceuticals and magnetic resonance imaging of the heart with contrast. Based on these tests a targeted ablation was performed which relieved the tachycardia, the impossibility of subsequent induction and the homogenization of the substrate until the disappearance of pathological symptoms.<br />The presented clinical case demonstrates the possibility of using non-invasive imaging methods to develop a personalized approach to VT ablation in patients with coronary artery disease. However, the diagnostic accuracy, prognostic ability and feasibility of using these methods require further study.</p><p>Received 8 April 2020. Revised 22 April 2020. Accepted 24 April 2020.</p><p><strong>Funding:</strong> The work is supported by a financial grant of the Russian Science Foundation (project No. 17-75-20118).</p><p><strong>Conflict of interest:</strong> Authors declare no conflict of interest.</p><p><strong>Author contributions</strong><br />Drafting the article: A.B. Romanov, S.M. Minin, N.A. Nikitin <br />Literature review: A.G. Filippenko, E.A. Morzhanaev, I.S. Peregudov <br />Illustrations: A.B. Romanov, S.V. Shayakhmetova, S.M. Minin, N.A. Nikitin, V.V. Shabanov <br />Critical revision of the article: A.B. Romanov, С.В. Шаяхметова, S.M. Minin, N.A. Nikitin, I.L. Mikheenko, V.V. Shabanov, D.V. Losik <br />Surgical treatment: A.B. Romanov <br />Final approval of the version to be published: A.B. Romanov, S.M. Minin, S.V. Shayakhmetova, N.A. Nikitin, A.G. Filippenko, I.L. Mikheenko, E.A. Morzhanaev, I.S. Peregudov, D.V. Losik, V.V. Shabanov</p>
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