Wave packet dynamics in hole Luttinger systems

For hole systems with an effective spin 3/2 we analyzed analytically and numerically the evolution of wave packets with the different initial polarizations. The dynamics of such systems is determined by the $4\times 4$ Luttinger Hamiltonian. We work in the space of arbitrary superposition of light- and heavy-hole states of the "one-particle system". For 2D packets we obtained the analytical solution for the components of wave function and analyzed the space-time dependence of probability densities as well as angular momentum densities. Depending on the value of the parameter $a=k_0d$ ($k_0$ is the average momentum vector and $d$ is the packet width) two scenarios of evolution are realized. For $a>>1$ the initial wave packet splits into two parts and the coordinates of packet center experience the transient oscillations or {\it Zitterbewegung} (ZB) as for other two-band systems. In the case when $a0$ remains almost cylindrically symmetric and the ripples arise at the circumference of wave packet. The ZB in this case is absent. We evaluated and visualized for different values of parameter $a$ the space-time dependence of angular momentum densities, which have the multipole structure. It was shown that the average momentum components can precess in the absence of external or effective magnetic fields due to the interference of the light- and heavy hole states. For localized initial states this precession has a transient character.Comment: 9 pages, 8 gigur

Association of C3435T (rs1045642) polymorphism of the MDR1 gene with the increased risk of colorectal cancer in russian females from Central Russia

The objective of this study was to examine associations of single nucleotide polymorphisms, rs1045642 within the MDR1 gene and rs1799930 within the NAT2 gene, with the risk of colorectal cancer (CRC) in the population of Central Russi

Adenine and guanine recognition of stop codon is mediated by different N domain conformations of translation termination factor eRF1

Positioning of release factor eRF1 toward adenines and the ribose-phosphate backbone of the UAAA stop signal in the ribosomal decoding site was studied using messenger RNA (mRNA) analogs containing stop signal UAA/UAAA and a photoactivatable cross-linker at definite locations. The human eRF1 peptides cross-linked to these analogs were identified. Cross-linkers on the adenines at the 2nd, 3rd or 4th position modified eRF1 near the conserved YxCxxxF loop (positions 125–131 in the N domain), but cross-linker at the 4th position mainly modified the tripeptide 26-AAR-28. This tripeptide cross-linked also with derivatized 3′-phosphate of UAA, while the same cross-linker at the 3′-phosphate of UAAA modified both the 26–28 and 67–73 fragments. A comparison of the results with those obtained earlier with mRNA analogs bearing a similar cross-linker at the guanines indicates that positioning of eRF1 toward adenines and guanines of stop signals in the 80S termination complex is different. Molecular modeling of eRF1 in the 80S termination complex showed that eRF1 fragments neighboring guanines and adenines of stop signals are compatible with different N domain conformations of eRF1. These conformations vary by positioning of stop signal purines toward the universally conserved dipeptide 31-GT-32, which neighbors guanines but is oriented more distantly from adenines

Bioethics in Russia: a Complex Scientific Discipline at the Intersection of Philosophy, Biology, Culture and Law

The article describes the formation of bioethics — a complex scientific discipline — in our country. The emergence of bioethics in the world dates back to the 1970s of the 20th century, in the Soviet Union it began to take shape during the period of perestroika as part of the activities of Academician Ivan Timofeevich Frolov (1929–1999). Bioethics deals with ethical issues that arise during the introduction of the latest biomedical technologies into practice, the solution of which can have various medical, cultural, legal, and financial consequences. The latest biomedical technologies open up new possibilities for a person (heredity management, genetic passport, etc.) and put a person in a situation of choice. Their future depends on what choice people will make, and this choice is determined by the state of the culture of society. In the field of bioethics, regulation is crucial and should be comprehensive and multi-stage. Philosophers, culturologists, and ethicists formulate general principles of regulation based on the ideology of humanism. Further on, scientists consider these recommendations and develop appropriate codes of conduct, while lawyers consolidate the new understanding within the legal system. The formation of such an integrated approach in Russia took place within the framework of scientific structures created by Academician I. T. Frolov, — the AllUnion Interdepartmental Center for Human Sciences, the Institute of Man of the Russian Academy of Sciences, the Russian National Committee on Bioethics (RNKB), the Russian Committee on Bioethics under the Commission of the Russian Federation for UNESCO. In these structures, expert work was carried out on the main documents related to the interaction of the Russian Federation with the Council of Europe in the field of bioethics. RNKB prepared expert opinions for the Department of European Cooperation of the Ministry of Foreign Affairs of the Russian Federation and the Department for International Humanitarian Cooperation and Human Rights of the Ministry of Foreign Affairs of the Russian Federation regarding Russia's accession to international conventions on bioethics

Reconstruction of the history of a thermokarst lake in the Mid-Holocene based on an analysis of subfossil Cladocera (Siberia, Central Yakutia)

© 2017, Pleiades Publishing, Ltd. This paper presents the results of a cladoceran analysis of a sediment core with a lenght of 382 cm collected from a pingo in alas Khara Bulgunnyakh located in Central Yakutia. Based on the Cladocera analysis results, the formation of the lake had started during the Holocene climatic optimum ~6600 cal. yrs. BP. The analysis of changes in the species composition of subfossil cladoceran communities made it possible to identify, on the basis of cluster analysis, four statistically significant ecological zones. The period of optimal conditions for the Cladocera community is defined by a complex evened community structure and numerous cladoceran remains in the sediments accumulated between 6500 and 6000 cal. yrs. BP. The history of the thermokarst water body development and existence reconstructed on the basis of the subfossil cladoceran analysis was rapid and short

КРОС-ПЛАТФОРМНЕ ОБ’ЄДНАННЯ ДАНИХ МІКРОМАСИВ-ЕКСПЕРИМЕНТІВ ТА ЙОГО ВПЛИВ НА ЗНАЧЕННЯ ГЕННОЇ ЕКСПРЕСІЇ ПРИ АНАЛІЗІ ЗРАЗКІВ РАКОВИХ ПУХЛИН МОЛОЧНОЇ ЗАЛОЗИ ЛЮДИНИ

Introduction. Currently advances in different fields of biology and medicine accumulated large amount of high-throughput microarray datasets. It allows comparing, merging and analyzing such data in order to get more informative and statistically significant results. However, the process of cross-platform microarray data integration is complicated by different platform designs, that is the kind of probes used, the hybridization paradigm, the labeling and production methods. Such characteristics of microarray platforms should be considered when analyzing datasets from one study and even more when merging datasets.В различных областях биологии и медицины накопилось значительное количество данных широкомасштабных исследований генной экспрессии с использованием микромасив-технологий. Поэтому возникает насущная необходимость в сравнении, объединении и анализе этих данных с целью повышения информативности и статистической достоверности результатов анализа.У різних галузях біології та медицини накопичилася значна кількість даних широкомасштабних досліджень генної експресії за використання мікромасив-технологій. Тому виникає нагальна потреба в порівнянні, об'єднанні й аналізі цих даних з метою підвищення інформативності та статистичної достовірності результатів аналізу. Однак, процес об'єднання результатів мікромасив-експериментів на базі крос-платформного аналізу ускладнений існуванням багатьох мікроарей-платформ, різних за технологією виготовлення, методикою нанесення проб на чип і різновидністю дизайну проб. Ці особливості кожного з досліджень повинні бути враховані при обробленні та аналізі результатів мікромасив-експериментів, отриманих як на однакових, так і на різних платформах

Hepatoprotective activity of 1,2,4-triazole-3-thione derivatives, which contains on c5-atomic carbon hydroxy(phenyl)methyl dependent

Relevance of pharmaceuticals with high efficiency and low cost for the prevention and treatment of diseases of the digestive system is unquestionable. It would be appropriate to mention that we carried out an analysis of a number of studies in which hepatoprotective effects of 1,2,4-triazole derivatives were carried out, and showed high hepatoprotective effects. Therefore, the search for hepatoprotectors in the series of 1,2,4-triazole derivatives has not only theoretical but also practical significance. The aim of our work was to study the first synthesized derivatives of 1,2,4-triazole-3-thione, which was containing substituents on C5 by carbon atom in conditions of tetrachormethane hepatitis. To model toxic hepatitis, a hepatotoxic xenobiotic, carbon tetrachloride, was used. The study of biochemical indicators of liver status was carried out 24 hours after the last injection of carbon tetrachloride. The ability of the test compounds to restore the integrity of hepatocyte membranes was determined by the anti-cytolytic effect (decrease in the activity of Alanine Aminotransferase (ALT), Aspartate Aminotransferase (AST)). According to the results of the study, it was found that among 43 test compounds, 5 are able to prevent survival at 85.71%. Thus, among the substances studied, compound 2c, which contributed 85.71% of the survival of the experimental animals and decrease 33.43% in ALT and 34.33% in AST. In this case, a very weak inverse dependence of the above indices was observed (r = -0.31). Some regularities of the chemical structure of the hepatoprotective action of 1,2,4-triazole derivatives have been established, so the survival of the experimental animals decreased with the introduction of a phenyl substituent of the starting thiones with N4

Establishment of diuretic activity indicators for (3-thio-4-R-4-H-1,2,4-triazole-5-yl)(phenyl)methanols and their derivatives

Diuretic drugs are drugs that, by blocking the transport systems of the renal tubules, promote the removal of excess electrolytes and water from the body, normalization of the internal environment. They eliminate edema, reduce the fluid content in the body cavity. Diuretic drugs differ in their chemical structure, the mechanism of action on the urinary tract function of the kidneys and on the mechanisms of regulation of this function. It should be noted that the use of the above mentioned agents can lead to undesirable side effects, such as nausea, vomiting, unpleasant sensations in the stomach, headache, facial hyperemia. To date, there is evidence that 5-R-1,2,4-triazole derivatives have diuretic activity. The advantage of synthetic triazole derivatives is that, along with the expressed pharmacological action of the compound, there are relatively low rates of acute and chronic toxicity, but almost no side effects. Therefore, it is important to create new low-toxic substances of derivatives (3-thio-4-R-4-H-1,2,4-triazole-3-yl)(phenyl)methanols and study their diuretic properties. The purpose of the work is the purposeful search for new low-toxic and highly effective diuretic compounds among the derivatives of (3-thio-4-R-4-H-1,2,4-triazole-5-yl)(phenyl)methanols. Materials and methods. To establish the influence of compounds, which have been synthesized at the Physical and Chemical Chemistry Department of ZSMU, the method of E. B. Berchin was used on the excretory function of kidneys. Experiments on diuretic activity were conducted at the Department of Clinical Pharmacy, Pharmacotherapy and MFE of FPE, Zaporizhzhia State Medical University. Results. The diuretic activity of derivatives (3-thio-4-R-4H-1,2,4-triazole-5-yl)(phenyl)methanols was investigated. The study and analysis of the obtained experimental data were compared with the reference diuretic hypothiazide. Regularities "structure – activity" were established. The studies indicate that (3-thio-4-R-4H-1,2,4-triazoles-3-yl)(phenyl)methanol are not able to exceed hypothiazide diuretic effect, but 4-(5-hydroxy(phenyl)methyl-4-phenyl-4H-1,2,4-triazolе-3-ylthiomethyl)benzonitrile showed the results closer to the reference drug. Conclusion. By the method of E.B. Berchin the diuretic activity of derivatives (3-thio-4-R-4H-1,2,4-triazol-5-yl)(phenyl)methanols was investigated. Derivatives (3-thio-4-R-4H-1,2,4-triazole-3-yl)(phenyl)methanols do not excee the diuretic action of hypothiazide. Patterns "structure – action" were established. The most active compound was 4-(5-hydroxy(phenyl)methyl-4-phenyl-4H-1,2,4-triazolе-3-ylthiomethyl)benzonitrile

Non-hemagglutinating flaviviruses: molecular mechanisms for the emergence of new strains via adaptation to European ticks

Tick-borne encephalitis virus (TBEV) causes human epidemics across Eurasia. Clinical manifestations range from inapparent infections and fevers to fatal encephalitis but the factors that determine disease severity are currently undefined. TBEV is characteristically a hemagglutinating (HA) virus; the ability to agglutinate erythrocytes tentatively reflects virion receptor/fusion activity. However, for the past few years many atypical HA-deficient strains have been isolated from patients and also from the natural European host tick, Ixodes persulcatus. By analysing the sequences of HA-deficient strains we have identified 3 unique amino acid substitutions (D67G, E122G or D277A) in the envelope protein, each of which increases the net charge and hydrophobicity of the virion surface. Therefore, we genetically engineered virus mutants each containing one of these 3 substitutions; they all exhibited HA-deficiency. Unexpectedly, each genetically modified non-HA virus demonstrated increased TBEV reproduction in feeding Ixodes ricinus, not the recognised tick host for these strains. Moreover, virus transmission efficiency between infected and uninfected ticks co-feeding on mice was also intensified by each substitution. Retrospectively, the mutation D67G was identified in viruses isolated from patients with encephalitis. We propose that the emergence of atypical Siberian HA-deficient TBEV strains in Europe is linked to their molecular adaptation to local ticks. This process appears to be driven by the selection of single mutations that change the virion surface thus enhancing receptor/fusion function essential for TBEV entry into the unfamiliar tick species. As the consequence of this adaptive mutagenesis, some of these mutations also appear to enhance the ability of TBEV to cross the human blood-brain barrier, a likely explanation for fatal encephalitis. Future research will reveal if these emerging Siberian TBEV strains continue to disperse westwards across Europe by adaptation to the indigenous tick species and if they are associated with severe forms of TBE

IFIT1 differentially interferes with translation and replication of alphavirus genomes and promotes induction of type I interferon

Alphaviruses are a group of widely distributed human and animal pathogens. It is well established that their replication is sensitive to type I IFN treatment, but the mechanism of IFN inhibitory function remains poorly understood. Using a new experimental system, we demonstrate that in the presence of IFN-β, activation of interferon-stimulated genes (ISGs) does not interfere with either attachment of alphavirus virions to the cells, or their entry and nucleocapsid disassembly. However, it strongly affects translation of the virion-delivered virus-specific RNAs. One of the ISG products, IFIT1 protein, plays a major role in this translation block, although an IFIT1-independent mechanism is also involved. The 5'UTRs of the alphavirus genomes were found to differ significantly in their ability to drive translation in the presence of increased concentration of IFIT1. Prior studies have shown that adaptation of naturally circulating alphaviruses to replication in tissue culture results in accumulation of mutations in the 5'UTR, which increase the efficiency of the promoter located in the 5'end of the genome. Here, we show that these mutations also decrease resistance of viral RNA to IFIT1-induced translation inhibition. In the presence of higher levels of IFIT1, alphaviruses with wt 5'UTRs became potent inducers of type I IFN, suggesting a new mechanism of type I IFN induction. We applied this knowledge of IFIT1 interaction with alphaviruses to develop new attenuated variants of Venezuelan equine encephalitis and chikungunya viruses that are more sensitive to the antiviral effects of IFIT1, and thus could serve as novel vaccine candidates