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1.
Sergio Ayala‐Mar Javier Donoso‐Quezada Roberto C. Gallo‐Villanueva Victor H. Perez‐Gonzalez Jos Gonzlez‐Valdez 《Electrophoresis》2019,40(23-24):3036-3049
Exosomes are nanovesicles secreted by most cellular types that carry important biochemical compounds throughout the body with different purposes, playing a preponderant role in cellular communication. Because of their structure, physicochemical properties and stability, recent studies are focusing in their use as nanocarriers for different therapeutic compounds for the treatment of different diseases ranging from cancer to Parkinson's disease. However, current bioseparation protocols and methodologies are selected based on the final exosome application or intended use and present both advantages and disadvantages when compared among them. In this context, this review aims to present the most important technologies available for exosome isolation while discussing their advantages and disadvantages and the possibilities of being combined with other strategies. This is critical since the development of novel exosome‐based therapeutic strategies will be constrained to the effectiveness and yield of the selected downstream purification methodologies for which a thorough understanding of the available technological resources is needed. 相似文献
2.
Clément Gallo 《Comptes Rendus Mathematique》2006,342(5):319-323
We give an upper bound on the growth rate of the Schrödinger group on Zhidkov spaces. In dimension 1, we prove that this bound is sharp. To cite this article: C. Gallo, C. R. Acad. Sci. Paris, Ser. I 342 (2006). 相似文献
3.
Fluoride effect on the palladium–phenanthroline catalyzed carbonylation of nitroarenes to carbamates
Michela Gasperini Fabio Ragaini Sergio Cenini Emma Gallo Simone Fantauzzi 《应用有机金属化学》2007,21(9):782-787
Fluorides promote the palladium–phenanthroline catalyzed carbonylation of nitroarenes to carbamates. The effect is more evident on the rate of the reaction at short reaction times, but a positive effect on selectivity is also observed under certain conditions. The effect is observed even under conditions under which chloride inhibits the reaction. Tetraethylammonium is a better countercation than sodium. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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Gallo E Caselli A Ragaini F Fantauzzi S Masciocchi N Sironi A Cenini S 《Inorganic chemistry》2005,44(6):2039-2049
A reproducible synthesis of a competent epoxidation catalyst, [Ru(VI)(TPP)(O)2)] (TPP = tetraphenylporphyrin dianion), starting from [Ru(II)(TPP)(CO)L] (L = none or CH3OH), is described. The molecular structure of the complex was determined by using ab initio X-ray powder diffraction (XRPD) methods, and its solution behavior was in detail investigated by NMR techniques such as PGSE (pulsed field gradient spin-echo) measurements. [Ru(IV)(TPP)(OH)]2O, a reported byproduct in the synthesis of [Ru(VI)(TPP)(O)2], was synthesized in a pure form by oxidation of [Ru(II)(TPP)(CO)L] or by a coproportionation reaction of [Ru(VI)(TPP)(O)2] and [Ru(II)(TPP)(CO)L], and its molecular structure was then determined by XRPD analysis. [Ru(VI)(TPP)(O)2] can be reduced by dimethyl sulfoxide or by carbon monoxide to yield [Ru(II)(TPP)(S-DMSO)2] or [Ru(II)(TPP)(CO)(H2O)], respectively. These two species were characterized by conventional single-crystal X-ray diffraction analysis. 相似文献
7.
The natural abundance 13C Fourier transform magnetic resonance spectra of rifamycin S and some of its derivatives have been studied. A combination of five different approaches has made unambiguous assignments for most of the resonances possible: (1) comparative study of the non- decoupled and noise-decoupled spectra; (2) 13C spectral characteristics; (3) spectral comparison between derivatives; (4) selective proton decoupling; (5) biogenetic evidence. Pulse and Fourier transform 13C NMR spectroscopy provides a more complete picture of these complex molecules than was previously obtained by 1H NMR spectroscopy. 相似文献
8.
The cyclic voltammetric technique is used to study hydrogen-bond formation in some polar organic solvents (S) of electroanalytical interest (1,2-dimethoxy, tetrahydrofuran, dimethylformamide, dimethyl sulphoxide and pyridine). The cathodic shift of the proton reduction caused by stepwise addition of the solvent investigated to a solution of anhydrous perchloric acid in acetonitrile is utilized. The theoretical treatment applied produced evidence that HS+ and HS+2 are the only acidic species involved, so that the relevant formation constants can be evaluated. The data obtained mostly compare well with those available in the literature. The features that condition the tendency to hydrogen-bonding and the effect of hydrogen bonding on solvent basicity are discussed. 相似文献
9.
The thermal decompositions of azodicarbamide (AZDICA), 2,2′-azobisisobutyronitrile (AIBN), benzoyl peroxide (Bz2O2), dicumyl peroxide (DICUP) andα, α′-bis(t.-butylperoxy)-m/p-diisopropylbenzene (PEROXIMON F) in binary and ternary mixtures containing low density polyethylene (LDPE) have been studied by means of DSC alone. Binary mixtures including 2% by weight of Bz2O2 or DICUP develop a decomposition heat of 64.2 and 59.1 J/g mixture, respectively. These values are higher than those measured for the decomposition of the pure peroxides. In all the ternary mixtures studied, containing LDPE, a peroxide and an azoderivative, the absolute enthalpic values attributed to the peroxide are lower than those obtained from the LDPE-peroxide mixtures. The enthalpy changes observed have been interpreted on the basis of interactions of the peroxide radicals with the polymer support and with the azo derivative. 相似文献
10.
Conejo-García A Campos JM Entrena A Sánchez-Martín RM Gallo MA Espinosa A 《The Journal of organic chemistry》2003,68(22):8697-8699
A complete study of the conformational behavior of 4,8-diaza-3(1,4),9(4,1)-dipyridina-1,6(1,4)-dibenzenacyclodecaphan-3(1),9(1)-bis(ilium) bishexafluorophosphate is described. This study allows us to conclude that the process observed by which the different chemical shifts of the pyridinium protons show coalescence at a high-temperature 1H NMR is the rotation around the C-N bond, whereas the conformational equilibrium between the four conformers is produced at low temperature. 相似文献