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Purpose: Analysis of infectious complications incidence in different types of percutaneous externalinternal biliary drainage in patients with obstructive jaundice of tumor genesis.Material and methods: The results of using antegrade external-internal drainage of the biliary tree in transpapillary and suprapapillary variants in 110 patients were analyzed. External-internal biliary drainage was performed in stages, after percutaneous transhepatic cholangiostomy or involuntarily primary with proximal obstruction of the biliary tree with bile duct segregation if it is impossible to form a fixing element of drainage proximal to the obstruction zone.Results: In the first group, transpapillary external-internal drainage was performed in 30 patients with peripapillary tumor obstruction. Of the 26 patients with proximal obstruction, suprapapillary external-internal drainage was performed in 8 patients, transpapillary — in 18 patients. Postmanipulation cholangitis in the first group occurred in 16 cases (28.6 %), liver abscesses developed 4 cases (7.1 %). In the second group, among 30 patients with transpapillary drainage on the background of peripapillary tumor obstruction, signs of acute cholangitis developed in 4 cases. Cholangitis was stopped by timely transfer of external-internal drainage to external. Among 24 patients with proximal obstruction of the biliary tree, suprapapillary external-internal drainage without complications was performed in 18 cases, transpapillary in 6 patients with the proximal block without disconnecting of the biliary tree. Acute cholangitis developed in 2 cases. Patients of the second group had no liver cholangigenic abscesses. There were no cases of hospital mortality in both groups.Conclusion: Factors in the development of postmanipulation cholangitis and liver abscesses during external-internal drainage of the biliary tree against the background of its tumor obstruction are the transpapillary position of endobiliary drainage with duodeno-biliary reflux in persistent biliary hypertension. In the case of suprapapillary location of the working end of external-internal drainage during antegrade drainage of the proximal tumor obstruction of the biliary tree with dissociation, the risk of postmanipulation cholangitis in non-drained liver segments is minimal. In the event of post-manipulation cholangitis in the case of transpapillary drainage of the biliary tree, a temporary transformation of external-internal drainage into external cholangiostomy is necessary.

The presented study analyzes the reasons for the need to move away from the US dollar (hereinafter referred to as the dollar) as a universal means of payment in international trade based on the existing threats, examines alternative means of international payments, and identifies their benefits and drawbacks in the context of Russia’s economic security.Aim. The study aims to identify and characterize the means of international payments that fall in line with Russia’s strategic priorities from the perspective of economic security.Tasks. The author considers the risks of using the dollar in international payments and reserves, assesses various means of international payments from the perspective of Russia’s strategic interests, and evaluates the possibility of substituting the dollar with alternative means of international payments.Methods. This study analyzes information from the International Economic Forums, statistics of the Central Bank of Russia, Federal State Statistics Service, Decree of the President of the Russian Federation on the economic security strategy of the Russian Federation until 2030, reports of news agencies, and works of Russian and foreign authors on the subject.Results. Based on the results of the conducted study, the author draws several conclusions. Due to many factors, the most important of them being the volume of trade in dollars, the dollar will remain the world’s leading currency in international trade. However, given that de-dollarization is a global process, the existing trends will amplify. A supranational currency is unlikely to appear for a number of reasons. First, the obvious opposition of the United States due to its unwillingness to let go of such a powerful lever of economic well-being and political influence as the use of the dollar as a global means of payment. The US would probably agree to creating a supranational currency in the medium term if the global process of de-dollarization reaches critical values. Second, the financial and trade centers of the euro and renminbi area are likely to focus on developing their own currencies, especially given the growing global GDP and China’s trade. Creating a supranational currency based on the existing structure of the International monetary Fund (hereinafter — the IMF), following the example of Special Drawing Rights (SDR), with the IMF virtually controlled by the United States, will not eliminate the threat of the currency being used as an instrument of political pressure on individual countries. Replacing the dollar with such kind of supranational currency does not serve the interests of Russia’s economic security. A potential alternative involves creating a supranational currency based on a structure that is independent of the IMF. In this case, the obstacles would include the obvious opposition of the US and its allies and the potential influence of the US on the emission of the supranational currency using its foreign political resources to affect the decisions made by other countries. Using national currencies in international trade in the medium term under the influence of globalization would lead to a formation of multiple currency centers. These centers would most likely be the dollar, euro, renminbi, and ruble.Conclusions. The creation of a ruble-based International Monetary Center with the CIS, BRIC countries (except China), and Turkey serves Russia’s strategic interests. Further consolidation around the ruble would require implementing a financial sustainability policy, maintaining the stability of the macroeconomic environment, creating an international bank similar to the IMF with payments made in rubles, strengthening offshore ruble areas, and increasing high-tech exports.

The purpose of this study was to substantiate the directions of reducing the damage to seeds during harvesting of grain crops. Threshing-separating devices of combine harvesters, physicomechanical characteristics of plants using wheat as an example, and parameters and modes of threshing devices that reduce grain damage were studied. It was revealed that grain damage is a consequence of the fact that parameters and operating modes of combines' threshing-separating devices are not consistent with harvested plants' characteristics. For threshing grain without damage, the shock pulse should be enough to separate the grain from inflorescence but be less than the force restricted by elastic properties (elastic limit) of the grain. The dependence of the average value of the bonding strength between the grain and the spike on the temperature and humidity, air temperature, and the standing time since reaching full ripeness can be described by a regression equation with a correlation coefficient of 0.89 and a determination coefficient of 0.79. This equation can be applied for the operational control of the rotational speed of the drum. For the operational control of feeding the harvested crop to the threshing device of the combine in the fields, the yield in individual sections of which varies significantly, methods developed for the introduction of precision farming are proposed. To obtain information on increasing the range between the bonding strength and elastic properties of the grain and to determine the dependence of the bonding strength between the grain and the spike on the properties of plants, it is necessary to study properties of both commercial and new cultivars.

The method of vibratory separation of grain from ear is validated in article. It is set that transferring to a stalk with ear low frequency oscillations in the range 18…100 Hz corresponding to natural frequencies of its oscillations are possible to achieve damage of ear or its detachment from a stalk as a result of a resonance. But this interval of oscillation frequencies does not provide separation of grains from ear as does not lead to damage of perular scales. Transmission to ear of high-frequency oscillations in the range 100…14000 Hz matching its natural frequencies of oscillations is perspective for this purpose. The mechanical resonance generate to grain separation owing to break off perular scales from ear can result from such vibratory influence.

Purpose. To determine the indications for the supra - and transpapillary externally-internal drainaging of the biliary tree in case of jaundice syndrome. Material and methods. The results of minimally invasive treatment of 246 patients with external-internal drainage of the biliary tree were analyzed. Among patients with proximal tumor block the external-internal drainage is made in 92 cases, in 42 (45,7%) out of them in suprapapillary embodiment and in 50 (54,3%) - via transpapillary approach. In 154 cases with distal tumor (obstruction peripapillary cancer) transpapillary drainage was performed. Results. The technical success of the external-internal drainaging was achieved in 242 patients (98,4%). It was failed to pass the duodenum in 4 patients with the cancer of common bile duct (3) and cancer of papilla of Vater (1). There was no complications related to the technique of external-internal drainage. In 18 patients (8,8%) out of 204 with transpapillary location of the drainage, we were forced to temporarily return to full outer bile outflow because of acute cholangitis. The syndrome of an acute blockade of the papilla of Vater arising after transpapillary external-internal drainaging required endoscopic papillosphincterotomy in 42 (84%) out of 50 patients with proximal tumor block bile outflow and in 7 (4.5%) out of 154 patients with peripapillary cancer. Conclusion. Suprapapillary and transpapillary embodiment of the drainage are equivalent in terms of the efficacy of cholestasis elimination. Syndrome of an acute blockade of papilla of Vater is the most often complication of the transpapillary external-internal drainage requiring the carrying out of endoscopic papillotomy «on drainage». This syndrome arises very frequently in a case of transpapillary external-internal drainage due to the proximal tumor obstruction of the biliary tree. The risk of acute cholangitis due to regurgitation after manipulation is absent in the suprapapillary location of the external-internal drainage, and with its transpapillary position is realized only with a concomitant violation of the outflow of bile.

The well-known working bodies for layer-by-layer soil-free tillage are characterized by high metal content, which leads to an increase in the weight of the structure and an increase in energy costs. The aim of the study is to reduce energy costs for the implementation of the technological process of layer-by-layer soil-free tillage. Due to the use of new non-metallic materials based on plastics in the design, it is possible to significantly reduce the metal capacity of working bodies and energy consumption for the process of layer-by-layer soil-free tillage. The article proves the expediency of using plastic in the structures of working bodies for soil cultivation. The choice of plastic should be based on analysis of its properties and characteristics. Tolerant to the change in the properties of the medium are high-molecular compounds of plastic with the flexibility of the polymer chain, which limits its steric hindrance to rotation and the interaction of groups of atoms. Thermoplasts obtained on the basis of branched polymers can be re-processed. These include polytetrafluoroethylene and polyethylene as the most appropriate conditions for agricultural production. The design of the working body for layer-by-layer soil-free tillage, containing a rack with a chisel, removable plowshares, crushing machine, thrust plate and ripper for small processing has been developed. In the local wear zones and areas of increased friction of the working body ultra-high molecular low-density polyethylene was mounted. The technique for optimizing the parameters of the working element for layer-by-layer soil-free tillage with the use of ultrahigh-molecular low-density polyethylene is based on the planning of the experiment on the three-factor Box plan. The smallest traction resistance and the minimum energy consumption of the working element for layer-by-layer soil-free tillage with the use of ultrahigh-molecular low-density polyethylene at a unit speed of 2.8 to 3.0 m/s are established; the angle of entry of the bit to soil from 31,5 to 33,5°; the depth of tillage is 30-35 cm.

Purpose. To discuss the possible causes of discrepancies in results of laboratory and X-ray methods of diagnostics of surgical cholestasis without a concomitant dilatation of the bile ducts, as well as features of X-ray-surgical tactics in such cases. Material and methods. In 2015-2016, 271 percutaneous transhepatic cholangiostomies were performed, including 23 cases - on unexpanded bile ducts, 7 these cancer patients with the laboratory evidence of cholestasis. The criteria for the absence of dilatation of the intrahepatic bile ducts were considered as not only an obvious non-visualized biliary tree on ultrasound, but also the diameter of the peripheral intrahepatic bile ducts less than 2 mm, which must be significantly less than similar peripheral branches of the portal vein. Results.Outside bile-outflow was effective, but only in two cases it provided the relief due to cholestasis performance. In 3 cases, blood bilirubin levels decreased by more than half of the initial ones. 5 out of 7 patients after external drainage of unexpanded bile ducts had evident signs of the liver failure. Two patients with malignant lesions of the biliary tree and baseline bilirubinemia over 450 umol/L died because of progressive liver failure. Conclusion. Mechanical jaundice corresponds to the concept of surgical cholestasis, which is associated with surgical diseases stipulating the violation of the outflow of bile and requires biliary decompression. By reducing the functional reserves of liver surgical cholestasis may not be accompanied by the significant expansion of the bile duct, which can be considered as a predictor of hepatic failure, which nevertheless requires cholangiostomy.

Show the possibility of an alternative use of interventional radiology techniques in complex treatment of patients with inflammatory complications of the diverticular disease of the colon.In 2012-2016, there were 87 patients under our supervision with complicated diverticular disease. In 57 (65.5%) cases were diagnosed infiltrate, in 24 (27.6%) cases - abscess of paracolon area (Ib-II type by Hinchey), in 6 (6.9%) cases (III-IV type according Hinchey) generalized peritonitis have been identified.Emergency laparotomy was performed in 13 patients. Abscesses of paracolon (Ib-II type by Hinchey) area were diagnosed sonographically during the initial examination in 17 patients. 26 percutaneous drainage of diverticulogenous abscesses of different localizations self-locking drainage #8Fr 'pig tail' was carried out under the combined ultrasonic and X-ray control in this group of patients. The technical success of percutaneous drainaging of the abscesses was achieved in all manipulations. 13 patients had a single drainaging, and for diverticular disease - disease-free during the observation period of 1 year to 5 years. Resection of the colon in a planned manner after percutaneous drainage of recurrent abscess of paracolon area was performed in 4 patients. Complications related with the technique of installing drainage were not reported, mortality in the group of drained patients was absent.Ultrasound examination of patients with suspected inflammatory complications of diverticular disease - a necessary and sufficient method for initial diagnosis of the disease. Percutaneous drainage of diverticulogenous abscesses (Hinchey Ib-II) is represented by the pragmatic 'first line' choice in patients with complicated diverticular disease, that allows to treat the pathology steadfastly in most of the cases.Цель - показать возможность альтернативного применения методик интервенционной радиологии в комплексном лечении пациентов с воспалительными осложнениями дивертикулярной болезни ободочной кишки. Материал и методы. В 2012-2016 гг. под нашим наблюдением находились 87 пациентов с осложненным течением дивертикулярной болезни. У 57 (65,5%) больных был диагностирован инфильтрат, у 24 (27,6%) - параколярный абсцесс (Ib-II тип по Hinchey), у 6 (6,9%) - распространенный перитонит (III-IV тип по Hinchey) [5, 9]. Результаты. По экстренным показаниям лапаротомия была выполнена в 13 наблюдениях. У 17 пациентов с параколярными абсцессами (Ib-II тип по Hinchey) диагноз был установлен сонографически при первичном обследовании. В этой группе больных было выполнено 26 перкутанных дренирований дивертикулогенных абсцессов разных локализаций самофиксирующимся дренажем pig tail 8Fr под сочетанным ультразвуковым и рентгенологическим контролем. У 13 пациентов дренирование было однократным, а течение дивертикулярной болезни - безрецидивным за время наблюдения от 1 года до 5 лет. Резекция толстой кишки в плановом порядке после перкутанного дренирования рецидивного параколярного абсцесса была выполнена у 4 пациентов. Осложнений, связанных с техникой установки дренажа отмечено не было, случаев летального исхода после дренирования не было. Технический успех перкутанного дренирования полости дивертикулогенного абсцесса был достигнут во всех манипуляциях. Вывод. Ультразвуковое обследование пациентов с подозрением на воспалительные осложнения дивертикулярной болезни - необходимый и достаточный метод первичной диагностики заболевания. Перкутанное дренирование дивертикулогенных абсцессов (Hinchey Ib-II) представляется прагматичным методом выбора первой линии у пациентов с осложненной дивертикулярной болезнью, позволяющим в большинстве наблюдений стойко купировать осложнение.

to analyze the efficacy of interventional methods in treatment of Klatskin tumor patients.Treatment of 133 patients with Klatskin tumor for the period 2000-2015 was analyzed. Bismuth I type was revealed in 28 (21.1%) cases, type II - in 45 (33.8%) cases, type III - in 51 (38.3%) cases, type IV - in 9 (6.8%) cases. All patients underwent sonofluoroscopy-assisted percutaneous transhepatic cholangiostomy using self-fixing Pig tail 8Fr drains at the first stage followed by externointernal drainage or antegrade biliary stenting. We deployed 1-6 drains simultaneously or step by step depending on severity of biliary occlusion.Technical success was achieved in all patients. Major postoperative complication such as drain dislocation followed by advanced biliary peritonitis was observed in 1 (0.8%) case. Minor complications occurred in 22 (16.5%) patients. In-hospital mortality was 7.5% (10 patients). The cause of death was severe liver-renal failure. Liver abscesses occurred in 13 patients after transpapillary externointernal drainage on background of temporary occlusion of biliary drain. This required interventional surgery.Obstructive jaundice management should be performed using interventional techniques simultaneously or step by step if unresectable tumor or inoperable patient are present. Herewith it is advisable to restore bile flow in maximal volume of liver parenchyma. Use of uncovered self-expanding biliary stents for palliative treatment of Klatskin tumor may be realized in «hybrid» variant to control stent patency as well as for neoadjuvant therapy of tumor.Материал и методы. Проведен анализ эффективности методов интервенционной радиологии с использованием антеградного чреспеченочного доступа в лечении 133 пациентов с опухолью Клацкина за период с 2000-2015 гг. Тип опухоли Bismuth I был выявлен в 28 (21,1%) наблюдениях, II - в 45 (33,8%), III - в 51 (38,3%) и IV - в 9 (6,8%) наблюдениях. Всем больным выполняли чрескожную чреспеченочную холангиостомию под сочетанным соно-флуороскопическим контролем с использованием на первом этапе самофиксирующихся дренажей Pig tail 8Fr с последующим наружновнутренним дренированием или антеградным эндобилиарным стентированием. Одномоментно и этапно в зависимости от распространенности билиарной окклюзии мы устанавливали от 1 до 6 дренажей. Результаты. Технический успех достигнут у всех пациентов. 'Большое' постманипуляционное осложнение - миграция холангиостомического дренажа с распространенным желчным перитонитом - встретилось в 1 (0,8%) наблюдении. 'Малые' осложнения развились у 22 (16,5%) пациентов. В стационаре умерли 10 (7,5%) пациентов. Причинами смерти стало прогрессирование печеночно-почечной недостаточности. У 13 пациентов, которым выполнено транспапиллярное наружновнутреннее дренирование, на фоне транзиторной блокады билиарного дренажа развились абсцессы печени, что потребовало дополнительных рентгенохирургических вмешательств для их санации. Выводы. При наличии очевидных признаков нерезектабельности опухоли и (или) неоперабельности пациента ликвидацию синдрома механической желтухи при опухолевом билиарном разобщении половин печени следует проводить чрескожно чреспеченочно одномоментно либо последовательно с двух сторон, стараясь восстановить желчединамику в максимально возможном объеме печеночной паренхимы. Использование непокрытых саморасширяющихся эндобилиарных стентов в паллиативном лечении опухоли Клацкина при билиарном разобщении половин печени может быть реализовано в 'гибридном' варианте как для текущего контроля за проходимостью стента, так и для проведения неоадъювантной терапии опухоли.Материал и методы. Проведен анализ эффективности методов интервенционной радиологии с использованием антеградного чреспеченочного доступа в лечении 133 пациентов с опухолью Клацкина за период с 2000—2015 гг. Тип опухоли Bismuth I был выявлен в 28 (21,1%) наблюдениях, II — в 45 (33,8%), III — в 51 (38,3%) и IV — в 9 (6,8%) наблюдениях. Всем больным выполняли чрескожную чреспеченочную холангиостомию под сочетанным соно-флуороскопическим контролем с использованием на первом этапе самофиксирующихся дренажей Pig tail 8Fr с последующим наружновнутренним дренированием или антеградным эндобилиарным стентированием. Одномоментно и этапно в зависимости от распространенности билиарной окклюзии мы устанавливали от 1 до 6 дренажей. Результаты. Технический успех достигнут у всех пациентов. «Большое» постманипуляционное осложнение — миграция холангиостомического дренажа с распространенным желчным перитонитом — встретилось в 1 (0,8%) наблюдении. «Малые» осложнения развились у 22 (16,5%) пациентов. В стационаре умерли 10 (7,5%) пациентов. Причинами смерти стало прогрессирование печеночно-почечной недостаточности. У 13 пациентов, которым выполнено транспапиллярное наружновнутреннее дренирование, на фоне транзиторной блокады билиарного дренажа развились абсцессы печени, что потребовало дополнительных рентгенохирургических вмешательств для их санации. Выводы. При наличии очевидных признаков нерезектабельности опухоли и (или) неоперабельности пациента ликвидацию синдрома механической желтухи при опухолевом билиарном разобщении половин печени следует проводить чрескожно чреспеченочно одномоментно либо последовательно с двух сторон, стараясь восстановить желчединамику в максимально возможном объеме печеночной паренхимы. Использование непокрытых саморасширяющихся эндобилиарных стентов в паллиативном лечении опухоли Клацкина при билиарном разобщении половин печени может быть реализовано в «гибридном» варианте как для текущего контроля за проходимостью стента, так и для проведения неоадъювантной терапии опухоли.

The conformational states of hexanucleotides 5′-d(GCATGC) and 5′-d(GCTAGC) capable of forming hairpins in aqueous solution were studied by 1D and 2D 1H NMR and molecular dynamics. The equilibrium thermodynamic parameters were determined for the formation of duplexes and hairpins, and the spatial structures were computed for the GCATGC and GCTAGC conformers. The mobility of the hexamer constituents was evaluated by nanosecond molecular dynamics simulation. The possible causes of the observed difference in the thermodynamic stability of the duplex and the hairpin are discussed.

Complex formation of hairpin-producing heptadeoxynucleotide 5'-d(GCGAAGC) with aromatic molecules: acridine dye proflavine and anthracycline antibiotic daunomycin was studied by one-dimensional 1H NMR and two-dimensional correlation 1H-1H (2M-TOCSY, 2M-NOESY), 1H-31P (2M-HMBC) NMR spectroscopy (500 and 600 MHz) in aqueous solution. Concentration and temperature dependences for the chemical shifts of ligand protons were measured, molecular models of equilibrium in solution were developed, and equilibrium thermodynamic parameters for the formation of intercalation complexes were calculated. Spatial structures of dye and antibiotic complexes with the heptamer hairpin were constructed on the basis of 2M-NOE data and the calculated values of limiting chemical shifts of ligand protons.

Self-association of hexadeoxynucleotide 5"-d(TpApCpGpTpA) and its complexation with antitumor antibiotic daunomycin were studied by one- and two-dimensional homonuclear 1H NMR spectroscopy and heteronuclear 1H–31P NMR spectroscopy in water–salt solution. The concentration and temperature dependences of proton chemical shifts of the hexadeoxynucleotide and the ligand were measured, and equilibrium constants and thermodynamic parameters of corresponding reactions were calculated on this basis using models for the formation of hexadeoxynucleotide duplex and its complex with the antibiotic. The spatial structure of daunomycin–d(TACGTA)2complex in solution was calculated using X-PLOR software on the basis of 2D NOE spectral data and the limit values of proton chemical shifts of the ligand. Comparative analysis of different intermolecular interactions in sequence-specific binding of the antibiotic to the DNA fragment was carried out.

Complexation of a phenanthridine dye ethidium bromide with a desoxyoligonucleotide 5’-d(GpApCpAp-TpGpTpC) in aqueous salt solution is studied by one- and two-dimensional1H NMR spectroscopy. Two-dimensional correlated homonuclear PMR spectroscopy (2D-TOCSY and 2D-N0ESY) was used for complete assignment of the proton signals of molecules in solution and for qualitative analysis of the character of interaction between ethidium bromide and desoxyoctanucleotide. The concentration dependences of the proton chemical shifts of the molecules were measured at three temperatures (T1 = 298 K, T2 = 308 K, and T3 = 318 K); the temperature dependences were measured in the temperature range 278–358 K. Different schemes of dye complexation with an octamer duplex involving different molecular associates in solution are considered. The equilibrium constants of the reactions, the corresponding thermodynamic parameters (δH0, δS0), and the limiting values of the chemical shifts of ethidium bromide protons in the complexes are determined. The relative contents of complexes of different types in solution (dye complexes with desoxyoctanucleotide in duplex form) are analyzed, and peculiarities of the dynamic equilibrium depending on the ratio of dye and octamer concentrations and temperature are established. The most probable structures of the 1:2 and 2:2 intercalated complexes corresponding to dye intercalation into the pyrimidine-purine sites of the desoxyoctanucleotide duplex are derived using the calculated values of the induced proton chemical shifts of ethidium bromide and two-dimensional PMR data.

Etude du caractere de la modulation incommensurable et du comportement du parametre d'ordre dans les cristaux presentant de l'incommensurabilite structurale et ayant differentes sequences de transitions de phases. Mesures des dependances angulaires de la decomposition quadripolaire et determination des tenseurs du gradient du champ electrique (EFG) de deux positions de Cs chimiquement non equivalents dans la phase a haute temperature

The conformational states of the self-complementary deoxyhexanucleotides d(GCATGC) and d(GCTAGC) capable of forming hairpin structures in aqueous solution have been studied by one- and two-dimensional 1H NMR spectroscopy and molecular dynamics simulations. The equilibrium thermodynamic parameters of the formation of duplex and hairpin forms have been determined, and the spatial structures of the d(GCATGC) and d(GCTAGC) conformers have been calculated. A comparative analysis of the thermodynamic and conformational parameters of self-association has been made. The molecular dynamics of the hexamer forms in the nanosecond time scale has been studied, and the mobility of their structural constituents has been evaluated. Possible reasons for the observed distinction in the thermodynamic stability of duplex and hairpin forms of the deoxyhexanucleotide sequences are discussed.

The self-association of self-complementary deoxyhexanucleotide d(GCATGC) was investigated in aqueous salt solution. Homonuclear 1H NMR correlation spectroscopy (2D-TOCSY and 2D-NOESY) was used for complete assignments of nonexchangeable protons of the hexamer. The equilibrium reaction constants and thermodynamical parameters of duplex d(GCATGC)2 formation were determined from experimental concentration and temperature dependences of proton chemical shifts of the deoxyhexanucleotide. Distinctive features of the concentration dependences in the range of small concentrations at relatively low temperatures of solution enable one to assume that one single-stranded hexamer sequence forms a compact structure (similar to a hairpin) in aqueous solution. A possible spatial hairpin structure of the hexamer was proposed. Comparative analysis of the experimental and theoretical (using the "nearest neighbor" model) thermodynamical parameters of duplex formation was made.

Complex formation of hairpin-producing heptadeoxynucleotide 5'-d(GCGAAGC) with aromatic molecules: acridine dye proflavine and anthracycline antibiotic daunomycin was studied by one-dimensional 1H NMR and two-dimensional correlation 1H-1H (2M-TOCSY, 2M-NOESY), 1H-31P (2M-HMBC) NMR spectroscopy (500 and 600 MHz) in aqueous solution. Concentration and temperature dependences for the chemical shifts of ligand protons were measured, molecular models of equilibrium in solution were developed, and equilibrium thermodynamic parameters for the formation of intercalation complexes were calculated. Spatial structures of dye and antibiotic complexes with the heptamer hairpin were constructed on the basis of 2M-NOE data and the calculated values of limiting chemical shifts of ligand protons.

Self-association of hexadeoxynucleotide 5'-d(TpApCpGpTpA) and its complexation with antitumor antibiotic daunomycin were studied by one- and two-dimensional homonuclear 1H NMR spectroscopy and heteronuclear 1H-31P NMR spectroscopy in water-salt solution. The concentration and temperature dependences of proton chemical shifts of the hexadeoxynucleotide and the ligand were measured, and equilibrium constants and thermodynamic parameters of corresponding reactions were calculated on this basis using models for the formation of hexadeoxynucleotide duplex and its complex with the antibiotic. The spatial structure of daunomycin-d(TACGTA)2 complex in solution was calculated using X-PLOR software on the basis of 2D NOE spectral data and the limit values of proton chemical shifts of the ligand. Comparative analysis of different intermolecular interactions in sequence-specific binding of the antibiotic to the DNA fragment was carried out.

The complex formation of the antibiotic daunomycin with deoxytetranucleotides of different base sequence in the chain, 5'-d(GpCpGpC), 5'-d(CpGpCpG), and 5'-d(TpGpCpA) in aqueous salt solution was studied by 1D and 2D (2M-TOCSY and 2M-NOESY) 1H-NMR spectroscopy. Concentration and temperature dependences of proton chemical shifts of molecules were measured. Based on these dependences, reaction equilibrium constants, relative content of various complexes depending on concentration and temperature, limiting values of chemical shifts of protons of daunomycin incorporated in various complexes, and the thermodynamic parameters delta H and delta S of complex formation were calculated. The analysis of the results enables the conclusion that the sites of predominant intercalation of daunomycin are triplet nucleotide sequences, the binding sites of the antibiotic with three consecutive GC pairs in the tetranucleotide duplex being more preferential. Daunomycin exhibits no sequence specificity upon binding to the single-stranded deoxynucleotide sequence. From the calculated values of induced chemical shifts of daunomycin protons and 2M-NOE data, the most probable spatial structures of complexes (1:2) of the antibiotic with deoxytetranucleotides were constructed. The binding of the second daunomycin molecule to both the single-stranded and duplex form of tetramers is of pronounced anticooperative mode, which is explained by the presence in the antibiotic of a positively charged amino sugar residue, which poses considerable steric constraints for the insertion of the second antibiotic molecule into the short tetranucleotide sequence. The results were compared with the data obtained under identical experimental conditions for typical intercalators proflavine and ethidium bromide.

The molecular basis of the action of caffeine as a complex forming agent, an interceptor of aromatic drugs intercalating into DNA was studied by the example of the an anticancer antibiotic actinomycin D examined. The hetero-association of caffeine and actionomycin D was studied by one- and two-dimensional 1H-NMR spectroscopy (500 MHz). Concentration and temperature dependences of the proton chemical shifts of molecules in aqueous solution were measured. The equilibrium reaction constant of hetero-association of caffeine with actinomycin D (K = 246 +/- 48 M-1), the limiting chemical shifts of caffeine protons in complexes were determined. The most favourable structure of the 1:1 caffeine-actinomycin D hetero-complex in aqueous solution was constructed using the calculated values of the induced proton chemical shifts of molecules and the quantum-mechanical iso-shielding curves for caffeine and actinomycin D. The thermo-dynamical parameters of the hetero-complex formation between caffeine and actinomycin D were also determined. The structural and thermo-dynamical analysis showed that dispersive forces and hydrophobic interactions play the major role in hetero-association of caffeine and actinomycin D in aqueous-salt solution. The relative content of different complexes in mixed solutions containing caffeine and actinomycin D was calculated and distinctive features of the dynamic equilibrium of caffeine-actinomycin D hetero-associates were revealed as a function of concentration and temperature. It is concluded that hetero-association of caffeine and actinomycin D molecules a lowers the effective concentration of the drug in solution and hence the pharmacological activity of actinomycin D.

The self-association of deoxyribohexanucleoside pentaphosphates 5'-d(CpGpTpApCpG) and 5'-d(CpGpCpGpCpG) in aqueous salt solutions was studied by 1 D- and 2 D homonuclear PMR and heteronuclear 1H-31P-spectroscopies. Signals from nonexchangeable protons of hexamers in NMR spectra were assigned using the available 2M-TOCSY, 2M-NOESY, and 1H-31P-(HMBS) spectra. The dependences of proton chemical shifts of deoxyhexanucleotides on concentration and temperature were measured. In terms of the two-states model (monomer-duplex), constants and thermodynamic parameters of self-association of hexamer molecules in solution were obtained based on these dependences. The values obtained correlate well with theoretical values calculated using the model of the "nearest neighbor" for the formation of duplexes of sequences d(CGTACG) and d(CGCGCG).

The influence of the course of hyperbaric oxygenation (HBO) on the peripheral blood lymphocytes chromosomes of 7 patients with different pathology and of 3 healthy volunteers was studied. It is proved that after HBO course the frequency of chromosome, aberrations of chromatid type hasn't been practically changed whereas the frequency of aberrations of chromosome type significantly decreases by three times on the whole.

The authors described the principle and algorithms of the separation of a summary radionephrogram into constituents, reflecting the contribution of a radiopharmaceutical, uptaken by neutrons, and RP in the surrounding tissues. The authors proposed a correct method for estimation (using the first constituent) of the efficacy indicator of RP uptake by the kidneys (Q-parameter) and the indicator of the mean time of transit (t) in the kidneys of RP uptaken by their parenchyma. The results of testing of the proposed methods of Q and t calculation were presented. Values of these parameters were determined in health and in essential hypertension, I and II degree, pyelonephritis, chronic nephritis (latent and hypertensive types), stenosis of the renal artery, obstruction of the upper urinary tracts, and in one kidney. These results indicate the physiological adequacy of the employed mathematical models, proving the diagnostic informative value of the calculated indicators.

A study of the cardiac ejection, peripheral tissue oxygen utilization, changes of lipoprotein cholesterol concentration, radical and antioxidant activity of blood plasma under the effect of hyperbaric oxygenation revealed that hyperbaric oxygenation stabilizes the cell membranes increasing the functional capacities of cells and organs manifested in an enhancement of the oxidation-reduction processes in the tissues, increase of the cardiac ejection and initially reduced concentrations of high-density lipoprotein cholesterol.

X-ray diffraction structural data, a PPP quantum chemical calculation, and IR and UV spectral indices indicate that there is a six-membered chelate formazyl group with syn, s-cis configuration and strong intramolecular hydrogen bonding is characteristic for 1-p-anisyl-3,5-diphenylformazane. Spectroscopic criteria were established for this configuration of the formazane molecule.

1. The crystal and molecular structures of N-(2-benzimidazolyl)-O-methyl carbamate and N-(2-benzimidazolyl)-O-ethyl carbamate have been determined. It was found that these compounds exist in the form of their tautomers (Ic) and (IIc). The spectroscopic characteristics (IR, EAS, and x-ray electronic spectrum) of N-(2-benzimidazolyl)-O-methyl carbamate were refined; these should prove beneficial in establishing the structures of metal complexes and salts of the indicated compounds. 2. It was also established that upon heating a solution of N-(2-benzimidazolyl)-O-methyl carbamate in ethanol in the presence of MnCl2-4H2O transesterification takes place to form N-(2-benzimidazolyl)-O-ethyl carbamate.

The work investigates the interaction of electrostatic surface waves at the plane boundary between a magnetoactive plasma and vacuum with an inhomogeneous beam of electrical oscillators moving outside the plasma parallel to its boundary. Expressions for the wave growth rates due to this interaction are obtained.

The propagation of slow surface waves along the plane boundary of two plasmas, along the plane plasma layer and along the plane vacuum layer in a plasma are investigated. The directions of the external magnetic field and the wave propagation are assumed to be arbitrary. Dispersion equations are derived and investigated. In some instances the frequencies of surface waves are obtained. The damping decrements resulting from the work done by the surface wave field on the plasma are determined.

1. In the reactions of o-allylphenol and of o-allylphenoxytrimethylsilane with alkoxy alkyl hydrogen silanes o-allylphenoxytrimethylsilane adds at its double bond to silicon, whereas in the case of o-allylphenol the hydroxyl group also reacts. 2. The alcoholysis of the products of the reaction of o-allylphenoxytrimethylsilane with alkoxy alkyl hydrogen silanes does not lead to the formation of organosilicon compounds containing a hydroxyphenyl group. In this reaction cyclic compounds are formed, and by the hydrolysis of these, polysiloxanes containing hydroxyphenyl groups, may be obtained. 3. Fifteen previously undescribed compounds were isolated and characterized.