The result of the treatment of atrial fibrillation using left atrial and biatrial or radiofrequency ablation procedures in patient's mitral valve surgery

Radiofrequency ablation is a method of atrial fibrillation treatment for. There are many publications on the effectiveness of this method, which sometimes include conflicting data. This paper presents a retrospective analysis of the treatment of mitral valve defects with the help of valve replacement and the use of RFA procedure for the recovery of permanent sinus rhythm in 131 patients. The ablation lines were laid with the help of ablators along the LA posterior wall, the mouths of the pulmonary veins (PVM) and in the right atrium (RA) according to the interpretation of "Labyrinth - 4" procedure. Patients were divided into two groups: those having undergone left atrial RFA only - 97 patients (74%), and biatrial RFA - 34 patients (26%). Operation time including RFA procedure in the general group, on average, was extended only by 13.5±1.3 minutes, the exposure time for each line corresponded to the achievement of transmural myocardial damage, and repeated three times. Postoperatively, 11 (8.4%) complications occurred. A correlation analysis showed that neither the preoperational size nor volume of the left atrium affect postoperatively the AF induction. All patients in the postoperative period had a significant reduction in the LA size, thereby leveling the possibility of occurrence of AF. In our group, regardless of bilateral or left atrial RFA, sinus rhythm was restored in 71% and 91% of cases, respectively. After two years, 65% of patients had sinus rhythm in bilateral RFA and 78% - in left atrial RFA

Gasotransmitters in regulation of neuromuscular transmission

© Springer-Verlag Berlin Heidelberg 2012. All rights are reserved. Nitric oxide (NO), carbon monoxide (CO), and hydrogen sulfide (H2S) are endogenously synthesized and serve as signaling molecules of autocrine and paracrine regulation in many systems. All three gases are produced in central nervous systems in response to neural excitation and regulate neurotransmitter release and are involved in the regulation of synaptic plasticity acting on pre- or postsynaptic levels. The modulatory mechanisms of these gases are different. In this chapter, we present the literature and our own data concerning the effects and mechanisms of these gases in the peripheral nervous system focusing on neuromuscular synapses. In motor nerve endings it was shown that NO decreased transmitter release while CO had the opposite effect. It was further shown that the main result of NO and CO action is a change of the cyclic adenosine monophosphate (cAMP) level which increased or decreased by cyclic guanosine monophosphate (cGMP) -dependent phosphodiesterases (PDEs) (2 or 3). H2S induced an increase of acetylcholine release and whose effect was mediated by cAMP and Ca2+. It is suggested that all three gases are produced at the neuromuscular junction and regulate transmitter release from motor nerve ending

Role of cGMP- and cAMP-dependent systems in the effects of nitric oxide on transmitter release and potassium currents in the frog neuromuscular junction

We studied the molecular mechanisms responsible for nitric oxide (NO)-evoked modulation of the synaptic function in the frog neuromuscular junction using inhibitors of adenylate and guanylate cyclases and analogs of cyclic nucleotides. It was shown that application of an exogenous donor of NO, sodium nitroprusside, decreased transmitter release and increased the amplitude of voltage-dependent potassium current of the nerve endings. Our results indicate that NO regulates transmitter release and potassium current in the frog neuromuscular junction both via cAMP- and cGMP-dependent mechanisms

Modulated by gasotransmitters: BK channels

© Springer-Verlag Berlin Heidelberg 2012. All rights are reserved. Calcium-activated potassium BK channels interconnect cellular activity, calcium signaling, and cell metabolism. Major virtues of these channels are their adaptability to different functions, their versatile physiology, and their capacity being modulated. The channels are present in a large variety of cells and organs in different forms of life from bacteria to men. Scientists attracted to these channels have produced a great wealth of information regarding their structure and function. Mutations at channels proteins are involved in a number of diseases (channelopathies), like diabetes, epilepsy, or heart failure. The gasotransmitters NO, CO, and H2S all act on BK channels directly or indirectly via signaling pathways. In this chapter, we will briefly summarize some of the basic properties of BK channels and focus on aspects of BK channel modulation by gasotransmitters and their implications in physiology and pathophyiology

Unconventional hydrocarbon reservoir zones in hypabyssal complexes of the basement of the tatar arch

© SGEM2017. All Rights Reserved. Within the crystalline basement of the Tatar arch of the East-Russian plate, specific zones are distinguished, which can be attributed to unconventional reservoir zones. According to previous studies, different types of genesis are generated: decompressed zones of destruction of great depths, weathering crusts at the boundary of the sedimentary cover and crystalline basement, fractured permeable zones subjected to later hydrothermal processes, etc. Formation of different types of reservoir zones is associated with individual stages of geodynamic evolution of the basement. Unconventional zones are of great interest that associated with the hypabyssal complexes of the rocks of the South Tatar arch. Such zones are established within various territories in the world, for example, in the basins of Australia, California in the USA, on the southern side of the Suez graben, and the West Siberian oil and gas province. In the Volga-Ural oil and gas province, such zones are allocated within the Kamsko-Belsky, Sernovodsko-Abdullinsky and Kamsko-Kinel aulacogenes of the South Tatar arch. We outlined the section of crystalline rocks of the Pervomaysky area with a detailed description of potential reservoir zones and various types of superimposed processes that form a void space of rocks

Participation of Russia in international agreements on author's right

The article deals with the international treaties of universal and regional nature in the field of authors' rights protection, which is a party to the Russian Federation. We have shown the system of contracts and their role in ensuring the protection of intellectual property rights on an international level, as well as its importance in respect of the aspect of authors' rights protection complicated by a foreign element, and harmonization of national legislation. It is concluded that the Russian Federation is a full member of the international authors' rights protection system that is the basis for the effective protection of the rights of foreign authors in Russia and Russian authors abroad, respectively

Effects of pyrocatechol on neuromuscular transmission

Effects of pyrocatechol on neuromuscular transmission were studied both in the frog pectoral-cutaneous muscle and in the mouse phrenic-diaphragmatic preparation by means of extracellular microelectrode recording of synaptic signals. Pyrocatechol applied in a concentration of 0.05 mM increased the frequency of miniature end-plate currents (MEPC) and the amplitude of end-plate current (EPC) by increasing its quantum content. Pyrocatechol also increased the duration of presynaptic response. When voltage-dependent potassium channels had been blocked, pyrocatechol affected neither the EPC quantum content nor the duration of presynaptic response. It is suggested that the pyrocatechol-induced enhancement of transmitter release results from modulatory effects of pyrocatechol on voltage-dependent potassium current in the membrane of a nerve terminal. © 1995 Plenum Publishing Corporation

Effects of hydrogen sulfide on the processes of exo- and endocytosis of synaptic vesicles in mouse motor nerve endings

The effects of sodium hydrosulfide(NaHS),the donor of hydrogen sulfide(H2S),on the exo-endocytosis cycle of the synaptic vesicles in the motor nerve ending of mouse diaphragm were explored using intracellular microelectrode technique and fluorescent microscopy. NaHS increased the frequency of miniature end-plate potentials(MEPPs) without changing its amplitude-time parameters and the amplitude of the postsynaptic responses undersingle stimulus condition(0.3 Hz),giving evidence on enhancing synaptic vesicle exocytosis. During high-frequency stimulation(50 Hz) NaHS induced more significant decline of neurotransmitter secretion,which can be due to the lower rate of synaptic vesicle mobilization from the recycling pool to the exocytic cites. NaHS also decreased the uptake of the fluorescent endocytic dye FM 1-43, which indicates the reduced endocytosis of the synaptic vesicles. Thus,the donor of H2S increased exocytosis and decreased the processes of the synaptic vesicles' endocytosis and mobilization in the mouse motor nerve ending

Mineralogical and geochemical features of the black sands of the south-west coast of India

© SGEM2017. All Rights Reserved. This article discusses a comprehensive study of the sand samples, which were selected on the Arabian seashores (Kovalam, Kollam, Kerala, India), and produced ilmenite, zircon, garnet and monazite concentrates (Chavara field, Kerala, India). As a result of versatile research, realized in the laboratories of KFU, which represented mineral and radionuclide composition of the studied samples, marginally represented La, Yb, Hf. Discovered free of impurities zircon, as well as zircon of the hafnium species. The studies show that the “black sands” of the coastal-marine zone of Kerala have heterogeneous composition. The predominant components are ore minerals (ilmenite, less – rutile). Other minerals are quartz, zircon, monazite, sillimanite, garnet. The investigated samples of the “black sands” contain an increased amount of radioactive chemical elements, through high content of monazite (with content of thorium-232). High concentrations of ore minerals on the coast at the expense the sea influence in the littoral areas, promotes removal of the light components and accumulation of heavy fractions

The functional state of the sympathoadrenal system and the autonomic regulation of the cardiac rhythm in younger schoolchildren

A comparative analysis of functional states of the sympathoadrenal system (SAS) and its reactions to isometric muscular effort was performed in seven-year-old schoolchildren of both sexes with different types of cardiac regulation. Children with a predominance of sympathetic influences displayed a higher excretion of noradrenaline and a lower excretion of dopamine than their counterparts with normal or vagal tone. A graded isometric exercise changed the functional state of the SAS in a manner dependent on the initial autonomic tone, baseline excretion of catecholamines, and sex. Boys displayed more strained reactions of the SAS than girls did, which was associated with a decrease in its reserve potential, especially pronounced in the states of vagal and normal tones. This suggests imperfect mechanisms of adaptation to static loads. © Pleiades Publishing, Inc. 2006