Electron spin resonance study of anisotropic interactions in a two-dimensional spin gap magnet PHCC

Fine details of the excitation spectrum of the two-dimensional spin-gap magnet PHCC are revealed by electron spin resonance investigations. The values of anisotropy parameters and the orientations of the anisotropy axes are determined by accurate measurements of the angular, frequency-field and temperature dependences of the resonance absorption. The properties of a spin-gap magnet in the vicinity of critical field are discussed in terms of sublevel splittings and g-factor anisotropy.Comment: submitted to PR

OUR EXPERIENCE IN TREATMENT OF CHILDISH ALLERGIC RHINOSINUITIS WITH HYDROCORTIS0N-PHON0PH0RESIS

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KALLIKREIN-KININ SYSTEM (KKS) AND ANGIOTENSIN CONVERTING ENZYME ACTIVITY (ACE) IN PATIENTS ON PERIODIC HA•MODIALYSIS (PHD) TREATED WITH RECOMBINANT HUMAN ERYTHROPOIETIN (rhEPO)

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Conventional Polychemotherapy of Acute Lymphoblastic Leukemia Patients Associated with Oxidative Stress and Antioxidants Depletion

The aim of this study was to investigate whether conventional polychemotherapy of acute lymphoblastic leukemia patients contributed to the development of oxidative stress and antioxidants depletion. Plasma levels of thiobarbituric acid-reactive substances assessed by malonedialdehyde (MDA) content were measured as products of lipid peroxidation. Pretreatment MDA values and MDA values during therapy course were estimated to be above the normal range, indicating the occurrence of oxidative stress. Serum iron levels were monitored as a potential source of non-transferrin bound iron with a role in initiation of oxidative burst. Increased serum iron levels were measured during the whole course of chemotherapy. To analyze the effects of cytostatic therapy on the pro-oxidant/antioxidant parameters in plasma we measured the total antioxidant status (TAS) and a single plasma antioxidant - uric acid (UA). A significant reduction of TAS levels was found at the end of the therapy course, strongly correlating with UA content (r=0,9; p<0,05). Our data suggest that uric acid as a routine laboratory indicator could also serve as a marker of blood antioxidant capacity

STUDY OF SOME INDICES OF KALLIKREIN-KININ SYSTEM AND OF ANGIOTENSIN-CONVERTING ENZYME (KININASE II) IN PLASMA OF RATS ON HEMOPERFUSION WITH NON-ION-EXCHANGE RESIN

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EFFECTIVENESS OF DIABETIC KETOACIDOSIS TREATMENT WITH LOW-DOSIS VENOUS INSULIN INFUSIONS

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The formation of oxidative disorders in the population of Vladivostok under the influence of atmospheric microparticles

We studied the response of trigger systems in healthy volunteers living in areas with different levels of air pollution. We determined that particles with the size of 800 microns and higher of relatively favorable region, particles with the size of less than 50 microns dominated in the air of the unfavorable area, among which there were the most hazardous to health amounts of microparticles - from 200 to 300 nm. Microparticles of unfavorable area causes the development of oxidative modifications of proteins and DNA contributing to the change of leukocyte potential energy. The increase in total antioxidant activity and response of thiol-disulfide system (the increase in thioredoxin, glutathione with a stable reductase level] maintains a balance of oxidation and antioxidant processes contributing to protection of the cellular and subcellular structures against considerable oxidative damage

Хемилюминесцентные реакции люминола и N-октиллюминола с гипохлоритом в неионогенных поверхностно-активных веществах

The chemiluminescent reaction of luminol is widely used for analytical purposes. Surface-active components of biological membranes are often present in biochemical studies and in many real objects of analysis. Their influence on the chemiluminescent reaction of luminol has not been systematically studied. Therefore, it is necessary to investigate this chemiluminescent reaction in organized molecular systems - micellar, vesicular and other systems simulating biological membranes. Micellar medium may also provide an additional opportunity to control chemiluminescent reactions, primarily with the aim of increasing their efficiency. The kinetics of the chemiluminescent oxidation of luminol and its hydrophobic analogue N-octylluminol with a hypochlorite ion in aqueous solutions and micellar solutions of non-ionic surfactant Triton X-100 was studied in the present work. It was shown that the growth and fading of the luminol and N-octylluminol chemiluminescence is adequately described by a two-exponential dependence, and the effective rate of increase in the intensity of chemiluminescence is directly proportional to the concentration of the hypochlorite ion. The dependences of the rate of accumulation and consumption of the intermediate product on the presence and concentration of surfactants in the reaction mixture are determined. The results are discussed in terms of the effect of localization of the reagents and intermediate reaction products.Хемилюминесцентная реакция люминола широко используется в аналитических целях. В биохимических исследованиях и во многих резальных объектах анализа зачастую присутствуют поверхностно-активные компоненты биологических мембран, влияние которых на хемилюминесцентную реакцию люминола систематически не изучалось. Отсюда возникает необходимость исследовать указанную хемилюминесцентную реакцию в организованных молекулярных системах - мицеллярных, везикулярных и иных, моделирующих биологические мембраны. Следует отметить также, что мицеллярная среда обеспечивает дополнительную возможность управления хемилюминесцентными реакциями, прежде всего, для повышения их эффективности. В настоящей работе исследована кинетика хемилюминесцентной реакции окисления люминола и его гидрофобного аналога - N-октиллюминола с гипохлоритионом в водных растворах и в мицеллярных растворах неионогенного поверхностно-активного вещества (ПАВ) Тритона X-100. Показано, что нарастание и затухание хемилюминесценции люминола и N-октиллюминола удовлетворительно описывается двухэкспоненциальной зависимостью, причем эффективная скорость нарастания интенсивности хемилюминесценции прямо пропорциональна концентрации гипохлорит-иона. Определены зависимости скорости накопления и гибели промежуточного продукта от наличия и концентрации ПАВ в реакционной смеси. Результаты обсуждаются с точки зрения влияния локализации исходных веществ и промежуточных продуктов на интенсивность хемилюминесцентных реакций