Coherent spin relaxation in molecular magnets

Numerical modelling of coherent spin relaxation in nanomagnets, formed by magnetic molecules of high spins, is accomplished. Such a coherent spin dynamics can be realized in the presence of a resonant electric circuit coupled to the magnet. Computer simulations for a system of a large number of interacting spins is an efficient tool for studying the microscopic properties of such systems. Coherent spin relaxation is an ultrafast process, with the relaxation time that can be an order shorter than the transverse spin dephasing time. The influence of different system parameters on the relaxation process is analysed. The role of the sample geometry on the spin relaxation is investigated.Comment: Latex file, 22 pages, 7 figure

СОРБЦИОННОЕ ИЗВЛЕЧЕНИЕ РЕНИЯ ИЗ ХРОМСОДЕРЖАЩИХ СУЛЬФАТНЫХ РАСТВОРОВ НИЗКООСНОВНЫМИ АНИОНИТАМИ СYBBER

Low-basic Cybber anionites with various functional groups and matrix type are tested for recovery of rhenium from multicomponent sulfuric acid solutions. It is established that anionite SX002 manifests an increased capacity during the sorption from solutions with a low Re content, while anionite ALX220 is applicable to recover Re at its high concentrations in the solution. The ionic background of the industrial solution affects the capacity of sorbents with respect to rhenium. When studying the kinetic characteristics, it is revealed that sorption processes on ionites are limited by the internal diffusion. The tests of ionites as applied to Cr-containing solutions indicate the possibility of using anionites ALX220 and SX002 to recover rhenium.Для извлечения рения из многокомпонентных серно-кислотных растворов опробованы образцы низкоосновных анионитов Cybber с различными функциональными группами и типом матрицы. Установлено, что анионит SX002 проявляет повышенную емкость при сорбции из растворов с низким содержанием Re, а ALX220 применим для извлечения Re при его высоких концентрациях в растворе. Ионный фон технологического раствора оказывает влияние на емкость сорбентов по рению. При изучении кинетических характеристик выявлено, что процессы сорбции на ионитах лимитируются внутренней диффузией. Проверка ионитов на технологических Cr-содержащих растворах свидетельствует о возможности применения анионитов ALX220 и SX002 для извлечения рения

Фармакоэпидемиологический анализ и анализ межлекарственных взаимодействий в терапии хронической почечной и печеночной недостаточности

Objective: to perform pharmacoepidemiological and drug interaction analysis of pharmacotherapy for liver/kidney transplantation.Material and methods. The study was conducted on the basis of multidisciplinary hospital in Nizhny Novgorod, which provides both therapeutic and high-tech surgical care. The object of the study was medical records of 34 patients who had undergone pharmacotherapy for liver/kidney transplantation. We evaluated the particularly dangerous moderate interactions that pose the greatest risk to patient health using Drugs.com electronic resource. Pharmacoepidemiologic assessment was performed using the ATC/DDD methodology (anatomical therapeutic chemical (ATC) classification system – defined daily dose (DDD)) recommended by the World Health Organization. The “average bed occupancy per year” was calculated using DDD per 100 bed-days. ABC analysis was used to estimate the costs of drug groups in therapy for liver/kidney transplantation. Results. In most cases, the third generation cephalosporins were used in the therapy of liver/kidney transplant patients (55.56% of all prescriptions). Antimicrobial drugs were mostly prescribed as monotherapy (61.9%). There were 111 potential major (14.41%) and moderate (72.07%) interactions detected. The largest number of moderate type risks was associated with changes in blood pressure levels (in 23.75% of cases – possible decrease, in 10% – increase), 7.5% of cases were accompanied by headaches, 6.25% – by reduction of drug effectiveness. In antimicrobial therapy, two main interactions were found: moxifloxacin – tacrolimus (arrhythmia), and metipred – moxifloxacin (tendon dystrophy), which is 12.5% of all main interactions for 21 case histories. In the ABC analysis, immunosuppressants were in group A (cost share 85.8%). Tacrolimus accounted for the largest amount of consumption: number of defined daily doses (NDDD) per year was 532.27 mg, NDDD per 100 bed days reached 432.18 (the highest among all drugs).Conclusion. Pharmacoepidemiologic analysis allows us to systematize data on medication use. The choice of drugs in order to ensure safe and effective use of the registered drug interactions is facilitated by electronic databases.Цель: проведение фармакоэпидемиологического анализа и анализа межлекарственных взаимодействий при фармакотерапии, сопровождающей трансплантацию печени/почек.Материал и методы. Исследование выполнено на базе многопрофильного стационара г. Нижнего Новгорода, оказывающего как терапевтическую, так и высокотехнологичную хирургическую помощь. Объект исследования – медицинские карты 34 пациентов, проходивших фармакотерапию при трансплантации печени/почек. Оценивали особо опасные умеренные взаимодействия лекарственных препаратов (ЛП), представляющие наибольший риск для здоровья пациента, с помощью электронного ресурса Drugs.com. Фармакоэпидемиологический анализ проводили с использованием рекомендуемой Всемирной организацией здравоохранения методологии ATC/DDD (англ. anatomical therapeutic chemical (ATC) classification system – анатомо-терапевтическо-химическая классификация, defined daily dose (DDD) – установленная суточная доза) по показателю DDD за 100 койко-дней, рассчитывали показатель «средняя занятость койки в году». С помощью ABC-анализа оценили затраты на группы ЛП в терапии при трансплантации почек или печени.Результаты. В большинстве случаев в терапии больных при трансплантации печени/почек применялись цефалоспорины третьего поколения (55,56% среди всех назначений). Антимикробные препараты использовали преимущественно в качестве монотерапии (61,9%). Всего обнаружено 111 потенциальных взаимодействий, среди которых основные (major) составили 14,41%, умеренные (moderate) – 72,07%. Наибольшее количество рисков умеренного типа связано с изменением уровня давления (в 23,75% назначений возможно снижение, в 10% – повышение), 7,5% случаев сопровождаются головными болями, 6,25% – снижением эффективности ЛП. При антимикробной терапии обнаружено два основных взаимодействия: моксифлоксацин – такролимус (аритмия) и метипред – моксифлоксацин (дистрофия сухожилий), что составляет 12,5% от всех основных взаимодействий по 21 истории болезни. При проведении АВС-анализа в группу А входят иммунодепрессанты (доля затрат 85,8%). Наибольшее количество потребления приходилось на такролимус: число установленных суточных доз (англ. number of defined daily doses, NDDD) в год составило 532,27 мг, а NDDD за 100 койко-дней – 432,18 мг, что является самым высоким показателем среди всех ЛП.Заключение. Фармакоэпидемиологический анализ позволяет систематизировать данные об использовании ЛП. Выбор ЛП с целью обеспечения безопасного и эффективного применения зарегистрированных межлекарственных взаимодействий упрощается при использовании электронных баз данных

The use of nonsteroidal anti-inflammatory drugs for the treatment of facial pain in practice

Studies have shown that the drug ibuprofen is effective for the relief of pain in the facial area, allowing the continuation of dental treatment. Clinical experience has shown that 87% of patients were satisfied with the result of pain relief.Проведенные исследования показали, что препарат ибупрофен является эффектив-ными для купирования болевого синдрома в лицевой области, что позволяет дальнейшее проведение стоматологического лечения. Клинический опыт показал, что 87% пациентов были удовлетворены результатом снятия болевого синдрома

Canonical wnt signaling activity in early stages of chick lung development

Wnt signaling pathway is an essential player during vertebrate embryonic development which has been associated with several developmental processes such as gastrulation, body axis formation and morphogenesis of numerous organs, namely the lung. Wnt proteins act through specific transmembrane receptors, which activate intracellular pathways that regulate cellular processes such as cell proliferation, differentiation and death. Morphogenesis of the fetal lung depends on epithelial-mesenchymal interactions that are governed by several growth and transcription factors that regulate cell proliferation, fate, migration and differentiation. This process is controlled by different signaling pathways such as FGF, Shh and Wnt among others. Wnt signaling is recognized as a key molecular player in mammalian pulmonary development but little is known about its function in avian lung development. The present work characterizes, for the first time, the expression pattern of several Wnt signaling members, such as wnt-1, wnt-2b, wnt-3a, wnt-5a, wnt-7b, wnt-8b, wnt-9a, lrp5, lrp6, sfrp1, dkk1, β-catenin and axin2 at early stages of chick lung development. In general, their expression is similar to their mammalian counterparts. By assessing protein expression levels of active/total β-catenin and phospho-LRP6/LRP6 it is revealed that canonical Wnt signaling is active in this embryonic tissue. In vitro inhibition studies were performed in order to evaluate the function of Wnt signaling pathway in lung branching. Lung explants treated with canonical Wnt signaling inhibitors (FH535 and PK115-584) presented an impairment of secondary branch formation after 48 h of culture along with a decrease in axin2 expression levels. Branching analysis confirmed this inhibition. Wnt-FGF crosstalk assessment revealed that this interaction is preserved in the chick lung. This study demonstrates that Wnt signaling is crucial for precise chick lung branching and further supports the avian lung as a good model for branching studies since it recapitulates early mammalian pulmonary development.Rute S. Moura was supported by a grant of ON.2 SR&TD Integrated Program (N-01-01-0124-01-07), ref: UMINHO/BPD/31/2013. The funders had no role in study design, data collection and analysis

Mutational Analysis of the Cyanobacterial Nitrogen Regulator PipX

PipX provides a functional link between the cyanobacterial global transcriptional regulator NtcA and the signal transduction protein PII, a protein found in all three domains of life as integrators of signals of the nitrogen and carbon balance. PipX, which is toxic in the absence of PII, can form alternative complexes with NtcA and PII and these interactions are respectively stimulated and inhibited by 2-oxoglutarate, providing a mechanism by which PII can modulate expression at the NtcA regulon. Structural information on PipX-NtcA complexes suggests that PipX coactivates NtcA controlled genes by stabilizing the active conformation of NtcA bound to 2-oxoglutarate and by possibly helping recruit RNA polymerase. To get insights into PipX functions, we perform here a mutational analysis of pipX informed by the structures of PipX-PII and PipX-NtcA complexes and evaluate the impact of point mutations on toxicity and gene expression. Two amino acid substitutions (Y32A and E4A) were of particular interest, since they increased PipX toxicity and activated NtcA dependent genes in vivo at lower 2-oxoglutarate levels than wild type PipX. While both mutations impaired complex formation with PII, only Y32A had a negative impact on PipX-NtcA interactions

Dianthracenylazatrioxa[8]circulene: synthesis, characterization and application in OLEDs

A soluble, green-blue fluorescent, pi-extended azatrioxa[8]circulene was synthesized by oxidative condensation of a 3,6-dihydroxycarbazole and 1,4-anthraquinone by using benzofuran scaffolding. This is the first circulene to incorporate anthracene within its carbon framework. Solvent-dependent fluorescence and bright green electroluminescence accompanied by excimer emission are the key optical properties of this material. The presence of sliding pi-stacked columns in the single crystal of dianthracenylazatrioxa[8]circulene is found to cause a very high electron-hopping rate, thus making this material a promising n-type organic semiconductor with an electron mobility predicted to be around 2.26 cm(2) V-1 s(-1). The best organic light-emitting diode (OLED) device based on the dianthracenylazatrioxa[8]circulene fluorescent emitter has a brightness of around 16 000 Cd m(-2) and an external quantum efficiency of 3.3 %. Quantum dot-based OLEDs were fabricated by using dianthracenylazatrioxa[8]circulene as a host matrix material.Peer reviewe

Detection and elimination of cellular bottlenecks in protein-producing yeasts

Yeasts are efficient cell factories and are commonly used for the production of recombinant proteins for biopharmaceutical and industrial purposes. For such products high levels of correctly folded proteins are needed, which sometimes requires improvement and engineering of the expression system. The article summarizes major breakthroughs that led to the efficient use of yeasts as production platforms and reviews bottlenecks occurring during protein production. Special focus is given to the metabolic impact of protein production. Furthermore, strategies that were shown to enhance secretion of recombinant proteins in different yeast species are presented

Stability of Yellow Fever Virus under Recombinatory Pressure as Compared with Chikungunya Virus

Recombination is a mechanism whereby positive sense single stranded RNA viruses exchange segments of genetic information. Recent phylogenetic analyses of naturally occurring recombinant flaviviruses have raised concerns regarding the potential for the emergence of virulent recombinants either post-vaccination or following co-infection with two distinct wild-type viruses. To characterize the conditions and sequences that favor RNA arthropod-borne virus recombination we constructed yellow fever virus (YFV) 17D recombinant crosses containing complementary deletions in the envelope protein coding sequence. These constructs were designed to strongly favor recombination, and the detection conditions were optimized to achieve high sensitivity recovery of putative recombinants. Full length recombinant YFV 17D virus was never detected under any of the experimental conditions examined, despite achieving estimated YFV replicon co-infection levels of ∼2.4×106 in BHK-21 (vertebrate) cells and ∼1.05×105 in C710 (arthropod) cells. Additionally YFV 17D superinfection resistance was observed in vertebrate and arthropod cells harboring a primary infection with wild-type YFV Asibi strain. Furthermore recombination potential was also evaluated using similarly designed chikungunya virus (CHIKV) replicons towards validation of this strategy for recombination detection. Non-homologus recombination was observed for CHIKV within the structural gene coding sequence resulting in an in-frame duplication of capsid and E3 gene. Based on these data, it is concluded that even in the unlikely event of a high level acute co-infection of two distinct YFV genomes in an arthropod or vertebrate host, the generation of viable flavivirus recombinants is extremely unlikely