Studies of fluxes of dissolved iron and manganese in the Gulf of Finland

© 2004 IEEE. Metal fluxes (total dissolved iron and manganese) across the water-sediment interface were studied in situ in the Gulf of Finland in June 2002 and 2003 using an autonomous benthic lander. Distribution of these metals in the sediment and the porewater was also investigated. Focus was given to understand the behavior of the studied metals at various redox conditions and the influence when sediment resuspension is occurring. Our data indicate the importance of the redox conditions for the iron fluxes with no fluxes at oxic, intermediate at anoxic and high fluxes at suboxic conditions. The fluxes of manganese do not seem to have any correlation with the oxygen levels. Both metals were significantly affected by resuspension, which led to a rapid release

Studies of contribution of metals bonded with organic matter of seawater to the fluxes of total dissolved metals across water-sediment interface at Vistula Lagoon of Baltic Sea

© 2004 IEEE. Investigations of fluxes of a dissolved element across the water-sediment interface in Vistula Lagoon (Baltic Sea) were carried out in August 2001 and 2002, using chamber experiments. Oxygen, iron(II), total dissolved iron, manganese, copper and lead fluxes were calculated. For the first time the fluxes of metals bonded with organic matter of sea water were studied. The contribution of metals bonded with organic matter to the total flux was varied depending upon conditions and may reach up to 70 %. It was found that metal fluxes at the coastal zone are larger than at the center of the lagoon by the factor of 2-4

Photothermal deflection determination of iron(II) with ferrozine with sorption preconcentration on silufol plates

Photothermal deflection spectroscopy was applied to the selective detection of iron(II) chelate with ferrozine by its sorption preconcentration on Silufol plates. The linearity range was 1 × 10-11-6 × 10 -8 mol cm-2 of chelate at the plate surface, which corresponded to 1 × 10-9 × 10-6 M of chelate in solution. The limits of detection and quantification are 8 × 10 -12 and 2.5 × 10-11 mol cm-2 at the plate from 15 μL of test solution (0.5 nM and 1.5 nM in solution, respectively), and the absolute detection limit is 8 fmol in the whole spot applied to a plate. Characteristics and features of photothermal deflection detection are discussed. © 2008 Society for Applied Spectroscopy

Інгібіторний потенціал каліксаренів відносно нуклеотидопірофосфатази/ фосфодіестерази 1

It has been previously shown that phosphonic acids covalently attached to the macrocyclic platform of calix[4]arenes are capable of inhibiting alkaline phosphatases. In this paper the effects of the upper-rim functionalized calix[4]arenes on the activity of nucleotide pyrophosphatase/phosphodiesterase 1 (NPP1) have been examined.Aim. To assess the inhibitory potential of calix[4]arene, thiacalix[4]arene and sulfonylcalix[4]arene derivatives against NPP1.Results and discussion. It has been found that calix[4]arene, thiacalix[4]arene, and sulfonylcalix[4]arene tetrakismethylphosphonic acids inhibit NPP1 with the IC50 values in the micromolar range. The derivatives of sulfonylcalix[4]arene demonstrated the selectivity of inhibition of NPP1 over alkaline phosphatases. In addition, sulfonylcalix[4]arene tetrakismethylphosphonic acid was able to inhibit the nucleotide pyrophosphatase/phosphodiesterase activity of the human serum. The possible mechanism of the inhibition has been discussed.Experimental part. The activity of NPP1 was monitored by spectrophotometry measuring the rate of hydrolysis of bis-p-nitrophenyl phosphate. The phosphodiesterase activity of the human serum was assessed in the presence of p-nitrophenyl ester of thymidine-5-monophosphate as a substrate. The homology model of the human NPP1 was generated based on the crystal structure of the murine enzyme. The molecular docking was performed using AutoDock 4.2.Conclusions. The results obtained have shown the ability of sulfonylcalix[4]arene derivatives to inhibit the activity of NPP1 in vitro, including the nucleotide pyrophosphatase/phosphodiesterase activity in the human blood serum.Ранее было показано, что фосфоновые кислоты, ковалентно присоединенные к макроциклической платформе каликс[4]аренов, способны ингибировать щелочные фосфатазы. В настоящей работе исследовано влияние производных каликс[4]арена на активность нуклеотидпирофосфатазы /фосфодиэстера-зы 1 (NPP1).Цель работы – оценить ингибиторный потенциал производных каликс[4]арена, тиакаликс[4]арена и сульфонилкаликс[4] арена относительно NPP1.                                                                         Результаты и их обсуждение. Установлено, что каликс[4]арен-, тиакаликс[4]арен- и сульфонилкаликс[4]арен-тетракис-метилфосфоновые кислоты ингибируют NPP1 со значениями IC50 в микромолярном диапазоне. Ингибирование NPP1 производными сульфонилкаликс[4]арена было селективным относительно щелочных фосфатаз. Кроме того, сульфонилкаликс[4]арен-тетракис-метилфосфоновая кислота способна ингибировать фосфодиэстеразную активность человеческой сыворотки. Обсуждается возможный механизм ингибирования.                       Экспериментальная часть. Активность NPP1 контролировали спектрофотометрически по скорости гидролиза бис-п-нитрофенилфосфата. Нуклеотидпирофосфатазную/фосфодиэстеразную активность человеческой сыворотки оценивали в присутствии п-нитрофенилового эфира тимидин-5-монофосфата в качестве субстрата. Гомологическая модель человеческой NPP1 была сгенерирована на основе кристаллической структуры мышиного фермента. Молекулярный докинг проводился с помощью программы AutoDock 4.2.                                                                                         Выводы. Полученные результаты показали способность производных сульфонилкаликс[4]арена ингибировать in vitro NPP1, в том числе нуклеотидпирофосфатазную/фосфодиэстеразную активность сыворотки крови человека.Раніше було показано, що фосфонові кислоти, ковалентно приєднані до макроциклічної платформи калікс[4]аренів, здатні інгібувати лужні фосфатази. В цій роботі вивчено вплив похідних калікс[4]арену на активність нуклеотидопірофосфатази /фосфодіестерази 1 (NPP1).Мета роботи – оцінити інгібіторний потенціал похідних калікс[4]арену, тіакалікс[4]арену та сульфонілкалікс[4]арену відносно NPP1.Результати та їх обговорення. Встановлено, що калікс[4]арен-, тіакалікс[4]арен- та сульфонілкалікс[4]арен-тетракіс-метилфосфонові кислоти інгібують NPP1 зі значеннями IC50 в мікромолярному діапазоні. Інгібування NPP1 похідними сульфонілкалікс[4]арену було селективним відносно лужних фосфатаз.Крім того, сульфонілкалікс[4]арен-тетракіс-метилфосфонова кислота здатна інгібувати нуклеотидопірофосфатазну/фосфодіестеразну активність людської сироватки. Обговорюється можливий механізм інгібування.Експерименальна частина. Активність NPP1 контролювали спектрофотометрично за швидкістю гідролізу біс-п-нітрофенілфосфату. Нуклеотидопірофосфатазну/фосфодіестеразну активність людської сироватки оцінювали з використанням п-нітрофенілового естеру тимідин-5-монофосфату як субстрату. Гомологічна модель людської NPP1 була згенерована на основі кристалічної структури мишачого ферменту. Молекулярний докінг проводили за допомогою програми AutoDock 4.2.Висновки. Отримані результати показали здатність похідних сульфонілкалікс[4]арену інгібувати активність NPP1 in vitro, в тому числі нуклеотидопірофосфатазну/фосфодіестеразну активність сироватки крові людини

Influence of natural oxygenation of Baltic proper deep water on benthic recycling and removal of phosphorus, nitrogen, silicon and carbon

At the end of 2014, a Major Baltic Inflow (MBI) brought oxygenated, salty water into the Baltic proper and reached the long-term anoxic Eastern Gotland Basin (EGB) by March 2015. In July 2015, we measured benthic fluxes of phosphorus (P), nitrogen (N) and silicon (Si) nutrients and dissolved inorganic carbon (DIC) in situ using an autonomous benthic lander at deep sites (170–210 m) in the EGB, where the bottom water oxygen concentration was 30–45 μM. The same in situ methodology was used to measure benthic fluxes at the same sites in 2008–2010, but then under anoxic conditions. The high efflux of phosphate under anoxic conditions became lower upon oxygenation, and turned into an influx in about 50% of the flux measurements. The C:P and N:P ratios of the benthic solute flux changed from clearly below the Redfield ratio (on average about 70 and 3–4, respectively) under anoxia to approaching or being well above the Redfield ratio upon oxygenation. These observations demonstrate retention of P in newly oxygenated sediments. We found no significant effect of oxygenation on the benthic ammonium, silicate and DIC flux. We also measured benthic denitrification, anammox, and dissimilatory nitrate reduction to ammonium (DNRA) rates at the same sites using isotope-pairing techniques. The bottom water of the long-term anoxic EGB contained less than 0.5 μM nitrate in 2008–2010, but the oxygenation event created bottom water nitrate concentrations of about 10 μM in July 2015 and the benthic flux of nitrate was consistently directed into the sediment. Nitrate reduction to both dinitrogen gas (denitrification) and ammonium (DNRA) was initiated in the newly oxygenated sediments, while anammox activity was negligible. We estimated the influence of this oxygenation event on the magnitudes of the integrated benthic P flux (the internal P load) and the fixed N removal through benthic and pelagic denitrification by comparing with a hypothetical scenario without the MBI. Our calculations suggest that the oxygenation triggered by the MBI in July 2015, extrapolated to the basin-wide scale of the Baltic proper, decreased the internal P load by 23% and increased the total (benthic plus pelagic) denitrification by 18%

Effect of a glutathione-containing dinitrosyl iron complex on the oxidative metabolic state and crystallogenic properties of rat blood plasma: a preclinical experimental study

Background: The multifaceted regulatory role of nitric oxide in biological systems predetermines the high value of studying the possibilities of the external control of the compound level in organs and tissues. There are several fundamentally different ways of exogenous modulation of nitric oxide metabolism. The most promising option is the use of pharmacological donors. Dinitrosyl iron complexes (DNIC) with various ligands hold a prominent place among such donors as they are considered as a natural deposited form of nitric oxide.Objective. To study the effect of a glutathione-containing dinitrosyl iron complex on the oxidative metabolism parameters and crystallogenic activity of rat blood.Methods. A preclinical experimental randomized study was conducted on 60 sexually mature male Wistar rats weighing about 250 g. The animals were divided into 6 groups, each consisting of 10 individuals. Group 1 included intact (without any manipulations) individuals. In group 2, the rats were administered daily intraperitoneal injections of 1 ml. of 0.9% sodium chloride solution for 10 days. The rats included in the other four groups received daily intraperitoneal injections of 1 ml of dinitrosyl iron complexes with glutathione ligands in an isotonic sodium chloride solution with different agent concentrations: 0.15 mM for group 3; 0.30 mM for group 4; 0.45 mM for group 5; 0.60 mM for group 6. The final indicator of the study was the assessment of the oxidative potential and crystallogenic properties of blood under the conditions of administering various doses of glutathione-containing dinitrosyl iron complexes. The following parameters were used to assess the activity of proand antioxidant systems: lipid peroxidation intensity; the total activity of antioxidant systems, and malondialdehyde concentration. The parameters for intrinsic crystallization assessment included serum facies structural index, crystallizability, assessment of the marginal facies zone, and the destruction degree of facies elements. The obtained data calculation was performed using the software packages MS Office 2013 (Microsoft Corporation, USA) and Statistica 10 (StatSoft, USA).Results. The research established that glutathione-containing dinitrosyl iron complexes have an antioxidant effect. Moreover, the manifestation of these properties demonstrates a nonlinear dependence on their dose, with a possible optimum lying in the range of 0.3–0.45 mM. The study also revealed a tendency towards crystallogenic properties activation induced by this agent, corresponding to concentrations of 0.3 and 0.45 mM.Conclusion. The undertaken studies indicate the presence of an antioxidant effect in glutathione-containing dinitrosyl iron complexes. The manifestation of these properties demonstrates a dependence on their dose with a possible optimum varying from 0.3 to 0.45 mM. The research has established the activating effect of glutathione-containing dinitrosyl iron complex injections on the crystallogenic potential of the blood serum of healthy rats. This effect consisted in an increase in the density and complexity of crystalline elements. What is more, the maximal manifestation of this tendency (for metabolic indicators as well) corresponded to concentrations of 0.3 and 0.45 mM

Coherent Pair Production by Photons in the 20-170 GeV Energy Range Incident on Crystals and Birefringence

The cross section for coherent pair production by linearly polarised photons in the 20-170 GeV energy range was measured for photon aligned incidence on ultra-high quality diamond and germanium crystals. The theoretical description of coherent bremsstrahlung and coherent pair production phenomena is an area of active theoretical debate and development. However, under our experimental conditions, the theory predicted the combined cross section and polarisation experimental observables very well indeed. In macroscopic terms, our experiment measured a birefringence effect in pair production in a crystal. This study of this effect also constituted a measurement of the energy dependent linear polarisation of photons produced by coherent bremsstrahlung in aligned crystals. New technologies for manipulating high energy photon beams can be realised based on an improved understanding of QED phenomena at these energies. In particular, this experiment demonstrates an efficient new polarimetry technique. The pair production measurements were done using two independent methods simultaneously. The more complex method using a magnet spectrometer showed that the simpler method using a multiplicity detector was also viable.Comment: 10 pages, 13 figures, 1 table, REVTeX4 two column, Version for publicatio

Linear to Circular Polarisation Conversion using Birefringent Properties of Aligned Crystals for Multi-GeV Photons

We present the first experimental results on the use of a thick aligned Si crystal acting as a quarter wave plate to induce a degree of circular polarisation in a high energy linearly polarised photon beam. The linearly polarised photon beam is produced from coherent bremsstrahlung radiation by 178 GeV unpolarised electrons incident on an aligned Si crystal, acting as a radiator. The linear polarisation of the photon beam is characterised by measuring the asymmetry in electron-positron pair production in a Ge crystal, for different crystal orientations. The Ge crystal therefore acts as an analyser. The birefringence phenomenon, which converts the linear polarisation to circular polarisation, is observed by letting the linearly polarised photons beam pass through a thick Si quarter wave plate crystal, and then measuring the asymmetry in electron-positron pair production again for a selection of relative angles between the crystallographic planes of the radiator, analyser and quarter wave plate. The systematics of the difference between the measured asymmetries with and without the quarter wave plate are predicted by theory to reveal an evolution in the Stokes parameters from which the appearance of a circularly polarised component in the photon beam can be demonstrated. The measured magnitude of the circularly polarised component was consistent with the theoretical predictions, and therefore is in indication of the existence of the birefringence effect.Comment: 12 pages, 12 figures, 1 table, REVTeX4 two column, Version for publicatio

Эффективность химиотерапии и стойкость клинического излечения у впервые выявленных больных деструктивным туберкулезом легких с позиций доказательной медицины

Summary. A randomized multicenter clinical study of chemotherapy efficacy, clinical cure and early recurrence rate involved 240 newly diagnosed patients with cavitary pulmonary tuberculosis treated in municipal and penitentiary medical facilities. Given the primary multiple drug resistance (MDR) of 22.5–33.3 %, intensive chemotherapy with isoniazid, rifampicin, pyrazinamide, ethambutol, kanamycin (or amikacin) and ofloxacin (or lev ofloxacin) allowed to achieve sputum conversion in 100 % of smearpositive patients using sputum microscopy and in 89.2 % using sputum culture, cavity closure in 71.7 %, and clinical cure in 94.2 % with early recurrence rate of 2.6 % in comparison to 54.2, 45.8, 45.8, 65 and 20.5 % respectively in patients treated with isoniazid, rifampicin, pyrazinamide and ethambutol. Lung fibrocavitary lesions with high level of MDR developed in 55 % of patients and were associated with high cost of treatment due to the need in expensive salvage chemotherapy regimens and hightech surgical inter ventions.Резюме. Было проведено рандомизированное многоцентровое клиническое исследование эффективности химиотерапии, клинического излечения и частоты ранних рецидивов у 240 впервые выявленных больных деструктивным туберкулезом легких в гражданских и пенитенциарных противотуберкулезных учреждениях. Доказано, что при уровне первичной множественной лекарственной устойчивости (МЛУ) 22,5–33,3 % режим химиотерапии изониазидом, рифампицином, пиразинамидом, этамбутолом, канамицином (амикацин) и офлоксацином (левофлоксацин) в интенсивной фазе лечения позволяет добиться прекращения бактериовыделения по результатам микроскопии мокроты у 100 % больных и по посеву – у 89,2 %, закрытия каверн – у 71,7 %, клинического излечения – у 94,2 % и ранних рецидивов – у 2,6 % пациентов. В то время как режим химиотерапии изониазидом, рифампицином, пиразинамидом, этамбутолом – у 54,2; 45,8; 45,8; 65 и 20,5 % больных соответственно. При этом в 55 % случаев констатировано формирование фибрознокавернозного туберкулеза с высоким уровнем вторичной МЛУ, что требует больших экономических затрат на дорогостоящие резервные препараты и высокотехнологичные оперативные вмешательства

Results on the Coherent Interaction of High Energy Electrons and Photons in Oriented Single Crystals

The CERN-NA-59 experiment examined a wide range of electromagnetic processes for multi-GeV electrons and photons interacting with oriented single crystals. The various types of crystals and their orientations were used for producing photon beams and for converting and measuring their polarisation. The radiation emitted by 178 GeV unpolarised electrons incident on a 1.5 cm thick Si crystal oriented in the Coherent Bremsstrahlung (CB) and the String-of-Strings (SOS) modes was used to obtain multi-GeV linearly polarised photon beams. A new crystal polarimetry technique was established for measuring the linear polarisation of the photon beam. The polarimeter is based on the dependence of the Coherent Pair Production (CPP) cross section in oriented single crystals on the direction of the photon polarisation with respect to the crystal plane. Both a 1 mm thick single crystal of Germanium and a 4 mm thick multi-tile set of synthetic Diamond crystals were used as analyzers of the linear polarisation. A birefringence phenomenon, the conversion of the linear polarisation of the photon beam into circular polarisation, was observed. This was achieved by letting the linearly polarised photon beam pass through a 10 cm thick Silicon single crystal that acted as a "quarter wave plate" (QWP) as suggested by N. Cabibbo et al.Comment: Presented at International workshop "Relativistic Channeling and Related Coherent Phenomena", Frascati (Rome) 23-26 March 200