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11.
Daria Kupczyk Renata Studziska Szymon Baumgart Rafa Bilski Tomasz Kosmalski Renata Koodziejska Alina Wo
niak 《Molecules (Basel, Switzerland)》2021,26(9)
Tumors are currently more and more common all over the world; hence, attempts are being made to explain the biochemical processes underlying their development. The search for new therapeutic pathways, with particular emphasis on enzymatic activity and its modulation regulating the level of glucocorticosteroids, may contribute to the development and implementation of new therapeutic options in the treatment process. Our research focuses on understanding the role of 11β-HSD1 and 11β-HSD2 as factors involved in the differentiation and proliferation of neoplastic cells. In this work, we obtained the 9 novel N-tert-butyl substituted 2-aminothiazol-4(5H)-one (pseudothiohydantoin) derivatives, differing in the substituents at C-5 of the thiazole ring. The inhibitory activity and selectivity of the obtained derivatives in relation to two isoforms of 11β-HSD were evaluated. The highest inhibitory activity for 11β-HSD1 showed compound 3h, containing the cyclohexane substituent at the 5-position of the thiazole ring in the spiro system (82.5% at a conc. 10 µM). On the other hand, the derivative 3f with the phenyl substituent at C-5 showed the highest inhibition of 11β-HSD2 (53.57% at a conc. of 10 µM). A low selectivity in the inhibition of 11β-HSD2 was observed but, unlike 18β-glycyrrhetinic acid, these compounds were found to inhibit the activity of 11β-HSD2 to a greater extent than 11β-HSD1, which makes them attractive for further research on their anti-cancer activity. 相似文献
12.
Dr. Szymon Chorazy Tomasz Charytanowicz Dr. Dawid Pinkowicz Junhao Wang Dr. Koji Nakabayashi Stephen Klimke Prof. Dr. Franz Renz Prof. Dr. Shin-ichi Ohkoshi Prof. Dr. Barbara Sieklucka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(36):15871-15879
A two-step hysteretic FeII spin crossover (SCO) effect was achieved in programmed layered Cs{[Fe(3-CNpy)2][Re(CN)8]}⋅H2O ( 1 ) (3-CNpy=3-cyanopyridine) assembly consisting of cyanido-bridged FeII-ReV square grid sheets bonded by Cs+ ions. The presence of two non-equivalent FeII sites and the conjunction of 2D bimetallic coordination network with non-covalent interlayer interactions involving Cs+, [ReV(CN)8]3− ions, and 3-CNpy ligands, leads to the occurrence of two steps of thermal SCO with strong cooperativity giving a double thermal hysteresis loop. The resulting spin-transition phenomenon could be tuned by an external pressure giving the room-temperature range of SCO, as well as by visible-light irradiation, inducing an efficient recovery of the high-spin FeII state at low temperatures. We prove that octacyanidorhenate(V) ion is an outstanding metalloligand for induction of a cooperative multistep, multiswitchable FeII SCO effect. 相似文献
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15.
We study the complete lattice of convergences, that is, of relations between a set and the set of its filters. Various properties of convergences (like isotonicity, antitonicity, being a pseudotopology, a pretopology, an adherence) determine subsets of the lattice of convergences which possess certain particular features called “cyrtological”. The morphisms associated to these sets, said “cyrtomorphisms”, are basic in the study of convergences. A method of generation of GALOIS connections relative to cyrtomorphisms is proposed. Semigroups generated by some cyrtomorphisms are analyzed. 相似文献
16.
The jump of the Milnor number of an isolated singularity f 0 is the minimal non-zero difference between the Milnor numbers of f 0 and one of its deformations (f s ). We prove that for the singularities in the X 9 singularity class their jumps are equal to 2. 相似文献
17.
We prove that for each universal algebra ${(A, \mathcal{A})}$ of cardinality ${|A| \geq 2}$ and infinite set X of cardinality ${|X| \geq | \mathcal{A}|}$ , the X-th power ${(A^{X}, \mathcal{A}^{X})}$ of the algebra ${(A, \mathcal{A})}$ contains a free subset ${\mathcal{F} \subset A^{X}}$ of cardinality ${|\mathcal{F}| = 2^{|X|}}$ . This generalizes the classical Fichtenholtz–Kantorovitch–Hausdorff result on the existence of an independent family ${\mathcal{I} \subset \mathcal{P}(X)}$ of cardinality ${|\mathcal{I}| = |\mathcal{P}(X)|}$ in the Boolean algebra ${\mathcal{P}(X)}$ of subsets of an infinite set X. 相似文献
18.
Karol?Ko?odziej Szymon?Szczypiński 《The European Physical Journal C - Particles and Fields》2009,64(4):645-651
We present results for the lowest order cross sections, calculated with the complete set of standard model Feynman diagrams,
of all possible detection channels of the associated production of the top quark pair and the light Higgs boson, which may
be used for determination of the top–Higgs Yukawa coupling at the future e
+
e
− linear collider. We show that, for typical particle identification cuts, the background contributions are large. In particular,
the QCD background contributions are much bigger than could be expected when taking into account a possibly low virtuality
of exchanged gluons. Moreover, we include the initial state radiation effects and discuss the dependence of the cross sections
on the Higgs boson and top quark masses. 相似文献
19.
Szymon G?a?b 《Topology and its Applications》2011,158(1):93-100
An ideal J of subsets of a Polish space X has (LK) property whenever for every sequence (An) of analytic sets in X, if lim supn∈HAn∉J for each infinite H then ?n∈G∉J for some infinite G. In this note we present a new class of σ-ideals with (LK) property. 相似文献
20.
Support-type properties of generalized convex functions 总被引:1,自引:0,他引:1
Szymon W?sowicz 《Journal of Mathematical Analysis and Applications》2010,365(1):415-747
Chebyshev systems induce in a natural way a concept of convexity. The functions convex in this sense behave in many aspects similarly to ordinary convex functions. In this paper support-type properties are investigated. Using osculatory interpolation, the existence of support-like functions is established for functions convex with respect to Chebyshev systems. Unique supports are determined. A characterization of the generalized convexity via support properties is presented. 相似文献