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41.
Maciej Fiedorowicz Jean Remy Galindo Michel Julliard Patrice Mannoni Michel Chanon 《Photochemistry and photobiology》1993,58(3):356-361
Abstract— Photodynamic induced cytotoxicity by Victoria blue BO (VB-BO), merocyanine 540 (MC540), Nile blue A (NB) and 4-tetrasulfonatophenyl-porphyrin (4-TSPP) has been studied on two human leukemic cell lines: K-562 and TF-1. Cells were incubated with dyes and irradiated with different doses of white light. Cell survival was assessed by propidium iodide (PI) staining using flow cytometry analysis. Concentrations of 5 x 10 8 M VB-BO were found to kill 75% of cells, and a concentration of 1 × 10−7 M induced more than 99% of cell killing. To obtain the same cytotoxic level, the presence of 2.6 × 10−5 M of MCS40 during irradiation was needed. Under the conditions used, NB was ineflective as a photosensitizer, although uptake studies showed that this dye was taken by the cells in much greater amounts than any other studied dye. Cell cycle distribution of TF-1 cells, surviving MC540 or VB-BO photoscnsitization has bccn studied by flow cytometry analysis after staining with Hoechst 33342 and PI. It was found that cells in G1 phase were slightly more resistant toward MCS40– and VB-BO-mediated photosensitization than cells in other phascs of the ccll cycle 相似文献
42.
The angular distributions of the analysing powers iT11(θ), T20(θ), T21(θ) and T22(θ) of the elastic scattering of polarized deuterons on deuterons have been measured at deuteron energies of 6.0, 8.0, 10.0 and 11.5 MeV. The vector component has small but non-zero values which change sign between 6.0 and 10.0 MeV. The tensor components have increasing values with increasing energy. The results are discussed in respect of resonances in 4He and a term scheme is proposed for a complete phase-shift analysis. 相似文献
43.
The total cross sections of some heavy-ion one-neutron transfer reactions involving 13C, which lead to excited states of one of the final nuclei, have been measured at energies below the Coulomb barrier. Products of the neutron spectroscopic factors in the initial and final states have been extracted using a Coulomb wave Born approximation, and have been compared with theory. 相似文献
44.
We point out the presence of He- ions in a duoplasmatron discharge and detect currents of 10-15 A. The influence of different parameters on this current is indicated and possible processes for the formation of He- ions are investigated. 相似文献
45.
Dr. Iwona Nierengarten Marc Nothisen Dr. David Sigwalt Thomas Biellmann Dr. Michel Holler Dr. Jean‐Serge Remy Dr. Jean‐François Nierengarten 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(51):17552-17558
Dendritic pillar[5]arene derivatives have been efficiently prepared by grafting dendrons with peripheral Boc‐protected amine subunits onto a preconstructed pillar[5]arene scaffold. Upon cleavage of the Boc‐protected groups, water‐soluble pillar[5]arene derivatives with 20 ( 13 ) and 40 ( 14 ) peripheral ammonium groups have been obtained. The capability of these compounds to form stable nanoparticles with plasmid DNA has been demonstrated by gel electrophoresis, transmission electron microscopy (TEM), and dynamic light scattering (DLS) investigations. Transfection efficiencies of the self‐assembled 13 /pCMV‐Luc and 14 /pCMV‐Luc polyplexes have been evaluated in vitro with HeLa cells. The transfection efficiencies found for both compounds are good, and pillar[5]arenes 13 and 14 show very low toxicity if any. 相似文献
46.
Dr. Mirela Pascu Mathieu Marmier Clément Schouwey Dr. Rosario Scopelliti Dr. Julian J. Holstein Dr. Gérard Bricogne Prof. Kay Severin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(19):5592-5600
The facile synthesis of anionic bipyridyl ligands with dinuclear clathrochelate cores is described. These metalloligands can be obtained in high yields by the reactions of M(ClO4)2(H2O)6 (M: Zn, Mn, or Co) with 4‐pyridylboronic acid and 2,6‐diformyl‐4‐methylphenol oxime or 2,6‐diformyl‐4‐tert‐butylphenol oxime, followed by deprotonation. The ligands are interesting building blocks for metallasupramolecular chemistry, as evidenced by the formation of a Pt‐based molecular square and four coordination polymers with 2D or 3D network structures. Competition experiments reveal that the utilization of anionic bipyridyl ligands can result in significantly more stable assemblies. 相似文献
47.
L. Jarczyk J. Lang R. MüllerA. Pollitzer J.F. ValleyW. Wölfli P. Marmier 《Physics letters. [Part B]》1972
The breakup of deuterons in the field of a gold nucleus has been measured at a deuteron energy of 12 MeV. The energy-angle correlations are compared with two different theoretical models which take into consideration only the Coulomb interaction. 相似文献
48.
Weifang Wang Taiko Oda Remy E.P. Mangindaan Kazuyo Ukai Michio Namikoshi 《Tetrahedron》2007,63(2):409-412
Three new sulfur-containing alkaloids, polycarpaurines A (1), B (2), and C (3) were isolated from the tropical ascidian Polycarpa aurata collected in Indonesia, together with six known compounds (4-9). The structures of new compounds were assigned on the basis of their spectral data. Compounds 1, 3, 4, and 8 inhibited colony formation of Chinese hamster V79 cells with EC50 values of 6.8, 8.6, 3.8, and 10 μM, respectively. Compounds 2 and 7 showed modest activity against V79 cells (EC50>10 μM). 相似文献
49.
Mapping Conformational Heterogeneity of Mitochondrial Nucleotide Transporter in Uninhibited States
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Dr. Remy Sounier Dr. Gaetan Bellot Dr. James J. Chou 《Angewandte Chemie (International ed. in English)》2015,54(8):2436-2441
One of the less well understood aspects of membrane transporters is the dynamic coupling between conformational change and substrate transport. NMR approaches are used herein to investigate conformational heterogeneity of the GTP/GDP carrier (GGC) from yeast mitochondria. NMR residual dipolar coupling (RDC) analysis of GGC in a DNA‐origami nanotube liquid crystal shows that several structured segments have different generalized degrees of order (GDO), thus indicating the presence of conformational heterogeneity. Complete GDO mapping reveals asymmetry between domains of the transporter and even within certain transmembrane helices. Nucleotide binding partially reduces local structural heterogeneity, and the substrate binds to multiple sites along the transport cavity. These observations suggest that mitochondrial carriers in the uninhibited states are intrinsically plastic and structural plasticity is asymmetrically distributed among the three homologous domains. 相似文献
50.
Remy T Baron GV Denayer JF 《Langmuir : the ACS journal of surfaces and colloids》2011,27(21):13064-13071
A model able to describe the effect of structural changes in the adsorbent or adsorbed phase during the dynamic (breakthrough) separation of mixtures on metal-organic frameworks (MOFs) is presented. The methodology is exemplified for a few pertinent case studies: the separation of xylene isomers and ethylbenzene on the flexible MOF MIL-53 and the rigid MOF MIL-47. At low pressures, no preferential adsorption of any component occurs on both MOFs. Contrarily, at higher pressures separation of ethylbenzene (EB) from o-xylene (oX) occurs on MIL-53 as a result of the breathing phenomenon within the MIL-53 structure. The increase in selectivity, starting from the gate-opening pressure, could be modeled by using a pressure-dependent saturation capacity for the most strongly adsorbed component oX. In the separation of m-xylene (mX) from p-xylene (pX) on the rigid MOF MIL-47, separation at higher pressures is a result of preferential stacking of pX. Here, the selectivity increases once the adsorption of pX switches from a single to a double file adsorption. By implementing a loading dependent adsorption constant for pX, the different unconventional breakthrough profiles and the observed selectivity profile on MIL-47 can be simulated. A similar methodology was used for the separation of EB from pX on MIL-47, where the separation is a result from steric constraints imposed onto the adsorption of EB. 相似文献