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141.
Gilmar F. Salgado Christian Cazenave Abdelaziz Kerkour Jean-Louis Mergny 《Chemical science》2015,6(6):3314-3320
Gathering structural information from biologically relevant molecules inside living cells has always been a challenging task. In this work, we have used multidimensional NMR spectroscopy to probe DNA G-quadruplexes inside living Xenopus laevis oocytes. Some of these structures can be found in key regions of chromosomes. G-quadruplexes are considered potential anticancer therapeutic targets and several lines of evidence indirectly point out roles in key biological processes, such as cell proliferation, genomic instability or replication initiation. However, direct demonstrations of the existence of G-quadruplexes in vivo are scarce. Using SOFAST-HMQC type spectra, we probed a tetramolecular G-quadruplex model made of d(TG4T)4 inside living Xenopus laevis oocytes. Our observations lead us to conclude that the quadruplex structure is formed within the cell and that the intracellular environment preferentially selects a conformation that most resembles the one found in vitro under KCl conditions. We also show for the first time that specific ligands targeting G-quadruplexes can be studied using high resolution NMR directly inside living cells, opening new avenues to study ligand binding discrimination under physiologically relevant conditions with atomic detail. 相似文献
142.
Belkacem Said‐Houari Abdelaziz Soufyane 《Mathematical Methods in the Applied Sciences》2015,38(17):3642-3652
In this paper, we consider the Bresse system coupled with the Fourier law of heat conduction. We prove that the decay rate of the solution is very slow. In fact, we show that the L2‐norm of the solution decays with the rate of (1 + t)?1/12 similar to the one obtained for the Timoshenko system. In addition, we found that the wave speed of the first two equations still control the decay rate of the solution with respect to the regularity of the initial data. This seems to be the first result dealing with the behavior of the Cauchy problem in the Bresse–Fourier model. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
143.
In this work we give sufficient conditions on the semigroup (T 0 (t)) t\geq0 , generated by the part of a Hille—Yosida operator in the closure of its domain, in order that certain perturbations preserve some regularity properties of (T 0 (t)) t\geq0 , like the norm continuity, compactness and differentiability. An application of our abstract results to retarded differential equations is given. 相似文献
144.
Guillaume Fiers Dr. Dalila Chouikhi Laurence Oswald Dr. Abdelaziz Al Ouahabi Dr. Delphine Chan‐Seng Prof. Laurence Charles Dr. Jean‐François Lutz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):17945-17948
Sequence‐defined peptide triazole nucleic acids (PTzNA) were synthesized by means of a solid‐phase orthogonal “AB+CD” iterative strategy. In this approach, AB and CD building blocks containing carboxylic acid (A), azide (B), alkyne (C), and primary amine (D) functions are assembled together by successive copper‐catalyzed azide–alkyne cycloaddition (CuAAC) and acid–amine coupling steps. Different PTzNA genetic sequences were prepared using a library of eight building blocks (i.e., four AB and four CD building blocks). 相似文献
145.
The di-n-butyltin(IV) and diethyltin(IV) fluorobenzoates [FC6H4COO]2SnR2 and (FC6H4COOR2Sn)2O have been synthesized and characterized spectroscopically. Their in vitro antitumor activity against two human tumor cell lines, MCF-7, a mammary tumor, and WiDr, a colon carcinoma, as well as against the NCI cell panel, is satisfactory. 相似文献
146.
Rudolph Willem Monique Biesemans Mohammed Boulam Ann Delmotte Abdelaziz El Khloufi Marcel Gielen 《应用有机金属化学》1993,7(5):311-317
The synthesis and characterization of tetraethylammonium (diorgano)halogeno(2, 6-pyridinedicarboxylato)stannates are described. The solution structures of these complexes in CDCl3 and DMSO are discussed on the basis of 119Sn and 19F NMR data. Their in vitro antitumour activities against two human tumour cell lines, MCF-7 and WiDr, are presented. 相似文献
147.
Generally, in the portfolio selection problem the Decision Maker (DM) considers simultaneously conflicting objectives such as rate of return, liquidity and risk. Multi-objective programming techniques such as goal programming (GP) and compromise programming (CP) are used to choose the portfolio best satisfying the DM’s aspirations and preferences. In this article, we assume that the parameters associated with the objectives are random and normally distributed. We propose a chance constrained compromise programming model (CCCP) as a deterministic transformation to multi-objective stochastic programming portfolio model. CCCP is based on CP and chance constrained programming (CCP) models. The proposed program is illustrated by means of a portfolio selection problem from the Tunisian stock exchange market. 相似文献
148.
A general synthetic approach for a novel range of bifunctional chelating agent (BCA) for the ‘fac-[M(CO)3]+‘ core (M=99mTc, 99Tc or Re) has been developed. The strategy includes the facile preparation of these tridentate ligands possessing a tertiary amine bearing two carboxylic acid functions as coordinating site and an aromatic amino group for coupling to a biovector. First complexation study has shown that these compounds act exclusively as tridentate ligands (via the two acids and the tertiary amine functions). The convenient synthesis of these new ligands coupled with their high affinity for Re(I) make them quite promising for biomedical applications. 相似文献
149.
150.
In this article we find the exact traveling wave solutions of the generalized nonlinear Schrödinger (GNLS) equation with variable coefficients using three methods via the generalized extended tanh-function method, the sine-cosine method and the exp-function method. The main objective of this article is to compare the efficiency of these methods by delivering the exact traveling wave solutions of the proposed nonlinear equation. 相似文献