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271.
In this short communication we describe a specific protocol for SDS-PAGE separation of adult bovine myosin heavy-chain (MyHC) isoforms. The conditions defined in this protocol allow a good separation with a good reproducibility of the four MyHC isoforms (MyHC I, IIa, IIx, IIb) identified in adult skeletal muscle of this species. This procedure uses mini-gel electrophoresis system and does not involve preparation of gradient separating gels. In addition, this protocol can also be applied to the electrophoretic separation of ovine and camel MyHC isoforms. 相似文献
272.
S. Picard D. Salloum P. Gougeon M. Potel 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):i61-i62
The crystal structure of dicaesium pentadecamolybdenum nonadecasulfide, Cs2Mo15S19, consists of a mixture of Mo6S8S6 and Mo9S11S6 cluster units in a 1:1 ratio. Both units are interconnected via inter‐unit Mo—S bonds. The Cs+ cations occupy large voids between the different cluster units. The Cs and two inner S atoms lie on sites with 3 symmetry (Wyckoff site 12c) and the Mo and S atoms of the median plane of the Mo9S11S6 cluster unit on sites with 2 symmetry (Wyckoff site 18e). 相似文献
273.
Nadine Leygue Aritz Perez e Iñiguez De Heredia Chantal Galaup Eric Benoist Laurent Lamarque Claude Picard 《Tetrahedron》2018,74(31):4272-4287
A series of four new 18-membered hexaaza macrocyclic ligands bearing three endocyclic pyridine units and acetate or methylenephosphonate pendant arms has been prepared. The new synthetic procedure is based on the use of amine and diamine precursors incorporating masked carboxylate or phosphonate functions and on an efficient sodium template effect which controls the crucial macrocyclization step (yields of macrocyclization reactions: 62–88%). This procedure appears as a suitable alternative compared to the classical Richman-Atkins methodology generally used for the preparation of this class of macrocycles. As demonstrated with the EuIII and TbIII complexes derived from two ligands, these tripyridinophane chelators form luminescent and stable mononuclear LnIII complexes in aqueous solution at physiological pH. In such a medium, TbIII complexes exhibit a brightness of 1700 (λexc?=?279?nm) and 3000 (λexc?=?268?nm)?M?1?cm?1. 相似文献
274.
Khadija Raouf-Benchekroun Claude Picard Pierre Tisnés Louis Cazaux 《Journal of inclusion phenomena and macrocyclic chemistry》1999,34(3):277-289
The synthesis of tetrathiolactams and related di- and tetrathioamide compounds is described. The formation constants of their heavy-metal complexes are determined by using the strong UV absorption of the thioamide chromophore. Extraction and transport abilities of tetrathioamide ionophores show selectivities for Ag(I) and Hg(II) cations over alkali, alkaline-earth or other heavy metal cations including transition metals such as Co(II). 相似文献
275.
Annamaria Jakab Serge Winter Marc Raccuglia Frank Picard Swati Dumitras Ralph Woessner Sanket Mistry Jayraj Chudasama Swati Guttikar Olivier Kretz 《Analytical and bioanalytical chemistry》2013,405(1):215-223
A simple, sensitive, and selective liquid chromatography/tandem mass spectrometry method was validated for the identification and quantification of mavoglurant (AFQ056) in human plasma. The chromatographic separation was performed using a Cosmosil 5 C18 (150?×?4.6 mm, 5 μm) column at 40?±?0.5 °C with a mobile phase consisting of acetic acid in water (0.1 %, v/v)/methanol (10:90, v/v) with a flow rate of 1.0 mL/min followed by quantification with tandem mass spectrometry, operating with electrospray ionization in positive ion mode and applying multiple reaction monitoring. The validated method described in this paper presents high absolute recovery with precision and accuracy meeting the acceptance criteria. The method was precise and accurate for 2- and 10-fold dilution of samples. The method was validated using sodium heparin as specific anticoagulant, and the anticoagulant effect was tested by lithium heparin and K3EDTA. The method was successfully cross-validated between two bioanalytical sites. The method was specific for mavoglurant within the given criteria for acceptance (apparent peak area at the retention time of mavoglurant in zero samples was less than 20 % compared with the mean peak area at LLOQ) in human plasma. The method was fully validated for the quantitative determination of mavoglurant in human plasma between the range of 2.00 and 2,500 ng/mL. 相似文献
276.
Jean Picard 《Probability Theory and Related Fields》1996,105(4):481-511
Summary We consider a Lévy processX
t and the solutionY
t of a stochastic differential equation driven byX
t; we suppose thatX
t has infinitely many small jumps, but its Lévy measure may be very singular (for instance it may have a countable support). We obtain sufficient conditions ensuring the existence of a smooth density forY
t: these conditions are similar to those of the classical Malliavin calculus for continuous diffusions. More generally, we study the smoothness of the law of variablesF defined on a Poisson probability space; the basic tool is a duality formula from which we estimate the characteristic function ofF. 相似文献
277.
The thrombin-specific inhibitor, hirudin variant rHV2-Lys 47 (rHirudin), is a 65-amino acid polypeptide produced by recombinant DNA technology in yeast. Previous studies have shown that the acidic C-terminal segment of hirudin is susceptible to enzymic degradation. To address the question of C-terminal-truncated forms of the protein in terms of by-products or metabolites, well-defined reference compounds are needed. We prepared nine derivatives by carboxypeptidase Y digestion of rHirudin followed by a two-step chromatographic purification. Liquid secondary ion mass spectrometric measurements performed on peptides collected after reversed-phase high-performance liquid chromatography showed three pure forms (1-64, 1-63 and 1-56) and three mixtures of two forms each (1-62 + 1-61, 1-58 + 1-57 and 1-55 + 1-54), which were readily distinguished from one another by their mass spectra. Further purification of these co-eluted samples was achieved by ion-exchange chromatography and their structures were confirmed by liquid secondary ion mass spectrometry. Preliminary studies conducted on intact rHirudin indicated that this is an excellent analytical tool for mass measurements of hirudin-related proteins. Indeed, it allowed rapid (within 10-15 min), precise (0.50 a.m.u. relative to expected value), reproducible (mean MH+ = 6907.64 +/- 0.42 a.m.u.), sensitive (up to 500 ng, i.e. 72 pmol) and specific measurement of the quasi-molecular ion (MH+) of the protein, and was thus readily applicable to the analysis of several derivatives. 相似文献
278.
A. Picard H. Backe J. Bonn B. Degen R. Haid A. Hermanni P. Leiderer A. Osipowicz E. W. Otten M. Przyrembel M. Schrader M. Steininger Ch. Weinheimer 《Zeitschrift für Physik A Hadrons and Nuclei》1992,342(1):71-78
This paper reports on precision measurements of conversion lines in the decay of83mKr with nuclear transition energies of 32.1 keV and 9.4 keV, respectively. The spectra were taken from a submonolayer surface of83m Kr frozen onto a cold backing, using the new Mainz solenoid retarding spectrometer. The high luminosity and resolution of this instrument enables the observation of all allowed conversion lines up to theN-shell and to fully separate the elastic component from inelastic satellites. The combined analysis of the data yields the transition energiesE y=32151.5±1.1 eV and 9405.9±0.8 eV, respectively. The experiment served also to pilot the application of this spectrometer to the question of a finite neutrino rest mass, searched for in theβ-decay spectrum of tritium and to problems in precision electron spectroscopy in general. 相似文献
279.