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1.
Mark B. Bushuev Viktor P. Krivopalov Dmitrii Yu. Naumov Katerina A. Vinogradova Lilia A. Sheludyakova Stanislav V. Larionov 《Inorganica chimica acta》2010,363(7):1547-13900
A new bidentate chelating pyrazolylpyrimidine ligand bearing a strong electron-donating substituent, i.e. 4-(3,5-diphenyl-1H-pyrazol-1-yl)-6-(piperidin-1-yl)pyrimidine (L) (Scheme 1), has been synthesized and used to obtain the copper(II) complexes by reaction with CuCl2. The molar ratio Cu:L = 1:2 leads to isolation of a complex having CuL2Cl2 empirical formula, while the molar ratio Cu:L = 1:1 gives a complex with CuLCl2 empirical formula. The crystal structure of L as well as the structures of both complexes were studied by single crystal X-ray diffraction. The crystal structure of CuL2Cl2 compound is formed by trans-[CuL2Cl2] mononuclear molecules. Surprisingly, in contrast to the previous compound having molecular structure, the crystal structure of CuLCl2 consists of mononuclear [CuL2Cl]+ complex cations and dinuclear [Cu2Cl6]2− anions. Thus, formula of CuLCl2 complex can be represented as [CuL2Cl]2[Cu2Cl6]. In both complexes molecules of L adopt bidentate chelating coordination mode through N2 atom of pyrazole and N3 atom of pyrimidine rings forming five-membered CuN3C metallocycles. Owing to C-H···N interactions and π-π-stacking L molecules form 2D network. In the structure of trans-[CuL2Cl2] there exist double lone pair(N(piperidine))-π(pyrimidine) interactions and C-H···Cl contacts resulting in the formation of 1D chains. Layered 2D structure of [CuL2Cl]2[Cu2Cl6] results from C-H···Cl, C-H···π and double lone pair(Cl([CuL2Cl]+ complex cation)-π(pyrimidine) interactions. 相似文献
2.
Natalia Kupriyanova Dmitrii Shibalev Alexander Voronov Kirill Netchvolodov Tatiana Kurako Alexei Ryskov 《Gene》2012
In eukaryotes, mature rRNA sequences are produced from single large (45S) precursor (pre-rRNA) as the result of successive removal of spacers through a series of rapid and intricate actions of endo- and exonucleases. The excision of internal transcribed spacer (ITS2), a eukaryotic-specific insertion, remains the most elusive processing step. ITS2 is the element mandatory for all eukaryotic pre-rRNAs that contain at least three processing cleavage sites for precise 5.8S and 28S formation. Conserved core sequences (cis-elements) binding to trans-factors provide for precise rRNA processing, whereas rapidly diverging regions between the core sequences preserve internal complementarity, which guarantees the spatial integrity of ITS2. Characteristic differences in the formation of such insertions during evolution should reflect the relationships between taxa. The phylogeny of the reptiles and the relationships between taxa proposed by scientists are controversial. To delineate the structural and functional features preserved among reptilian ITS2s, we cloned and sequenced 58 ITS2s belonging to four reptile orders: Squamata, Crocodilians, Aves, and Testudines. We studied the subsequent alignment and folding of variable regions. The sizes and packing of the loop–stems between conserved consensus segments in reptiles vary considerably between taxa. Our phylogenetic trees constructed on the basis of the reptile ITS2s primary structural alignments revealed a split between Iguania clade and all other taxa. True lizards (suborder Scleroglossa) and snakes (suborder Serpentes) show sister relationships, as well as the two other reptilian orders, Crocodilia + Aves and Testudines. In summary, our phylogenetic trees exhibit a mix of specific features deduced or, to the contrary, rejected earlier by other authors. 相似文献
3.
Zakhar O. Shenkarev Mikhail A. Shulepko Maxim L. Bychkov Dmitrii S. Kulbatskii Olga V. Shlepova Nathalia A. Vasilyeva Alexander A. Andreev-Andrievskiy Anfisa S. Popova Evgeniya A. Lagereva Eugene V. Loktyushov Sergey G. Koshelev Morten S. Thomsen Dmitry A. Dolgikh Sergey A. Kozlov Pavel M. Balaban Mikhail P. Kirpichnikov Ekaterina N. Lyukmanova 《Journal of neurochemistry》2020,155(1):45-61
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Carmi Y Rinott G Dotan S Elkabets M Rider P Voronov E Apte RN 《Journal of immunology (Baltimore, Md. : 1950)》2011,186(6):3462-3471
Inflammatory cytokines modulate immune responses in the tumor microenvironment during progression/metastasis. In this study, we have assessed the role of IL-1 and IL-17 in the control of antitumor immunity versus progression in a model of experimental lung metastasis, using 3LL and B16 epithelial tumor cells. The absence of IL-1 signaling or its excess in the lung microenvironment (in IL-1β and IL-1R antagonist knockout [KO] mice, respectively) resulted in a poor prognosis and reduced T cell activity, compared with WT mice. In IL-1β KO mice, enhanced T regulatory cell development/function, due to a favorable in situ cytokine network and impairment in APC maturation, resulted in suppressed antitumor immunity, whereas in IL-1R antagonist KO mice, enhanced accumulation and activity of myeloid-derived suppressor cells were found. Reduced tumor progression along with improved T cell function was found in IL-17 KO mice, compared with WT mice. In the microenvironment of lung tumors, IL-1 induces IL-17 through recruitment of γ/δ T cells and their activation for IL-17 production, with no involvement of Th17 cells. These interactions were specific to the microenvironment of lung tumors, as in intrafootpad tumors in IL-1/IL-17 KO mice, different patterns of invasiveness were observed and no IL-17 could be locally detected. The results highlight the critical and unique role of IL-1, and cytokines induced by it such as IL-17, in determining the balance between inflammation and antitumor immunity in specific tumor microenvironments. Also, we suggest that intervention in IL-1/IL-17 production could be therapeutically used to tilt this balance toward enhanced antitumor immunity. 相似文献
6.
Diana P. Trebec‐Reynolds Irina Voronov Johan N.M. Heersche Morris F. Manolson 《Journal of cellular biochemistry》2010,109(5):975-982
Interleukin 1 (IL‐1) is a proinflammatory cytokine upregulated in conditions such as rheumatoid arthritis and periodontal disease. Both isoforms, IL‐1α and IL‐1β, have been shown to activate osteoclasts (OCs), the cells responsible for resorbing bone. Inflammatory conditions are also characterized by increased bone loss and by the presence of large OCs (10+ nuclei). We and others have previously shown that large OCs are more likely to be resorbing compared to small OCs (2–5 nuclei). Moreover, large OCs express higher levels of the IL‐1 activating receptor IL‐1RI, integrins αv and β3, RANK, and TNFR1, while small OCs have higher levels of the decoy receptor IL‐1RII. We hypothesized that IL‐1 would have different effects on large and small OCs due to these distinct receptor expression patterns. To test this hypothesis, RAW 264.7 cells were differentiated into populations of small and large OCs and treated with IL‐1α or IL‐1β (1 and 10 ng/ml). In the presence of sRANKL, both IL‐1α and IL‐1β increased total OC number and resorptive activity of large OCs. IL‐1α stimulated formation of large OCs and increased the number of resorption pits, while IL‐1β changed the morphology of large OCs and integrin‐β3 phosphorylation. No effects were seen in small OCs in response to either IL‐1 isoform. These results demonstrate that IL‐1 predominantly affects large OCs. The dissimilarity of responses to IL‐1α and IL‐1β suggests that these isoforms activate different signaling pathways within the two OC populations. J. Cell. Biochem. 109: 975–982, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
7.
Lunina O. N. Savvichev A. S. Babenko V. V. Boldyreva D. I. Kuznetsov B. B. Kolganova T. V. Krasnova E. D. Kokryatskaya N. M. Veslopolova E. F. Voronov D. A. Demidenko N. A. Letarova M. A. Letarov A. V. Gorlenko V. M. 《Microbiology》2019,88(1):100-114
Microbiology - The community of anoxygenic phototrophic bacteria (APB) from the water column of the meromictic Lake Trekhtsvetnoe (Kandalaksha Bay, White Sea, Russia) was studied in March 2012 and... 相似文献
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Alexander V. Lukashin Dmitrii B. Beglov Maxim D. Frank-Kamenetskii 《Journal of biomolecular structure & dynamics》2013,31(3):517-523
Abstract In order to allow for real dielectric properties of a solvent in calculating of electrostatic characteristics of strongly charged polyions such as DNA in salt solution we consider a simple model of linear dielectric response of a medium. The interactions between charged particles are treated in the framework of self-consistent-field approximation. The basic characteristic of the problem, electrostatic potential, can be found from the solution of non-linear integro-differential equation. Specifically we consider so-called quasimacroscopic model where dielectric response of a medium depends only on the distance from the polyion. Application of the approach for calculating of the B-to-Z free energy qualitatively retains the main conclusion obtained previously within the model with fixed dielectric constant: non-monotonous behavior of the free energy difference as a function of ionic strength. At the same time, essential sensitivity of the results to specific values of dielectric parameters is observed. 相似文献