Search results for "Mechanism"
showing 10 items of 1835 documents
Editorial: Pathophysiologic Insights From Biomarker Studies in Neurological Disorders
2020
Adipose stromal cells promote the transition of colorectal cancer cells toward a mesenchymal-like phenotype
2021
ABSTRACT Colon cancer progression is among the risks that increase with obesity. We have recently unveiled the molecular mechanism by which adipose tissue-released molecules, HGF and IL-6, make colorectal cancer (CRC) cells acquiring mesenchymal traits. Targeting of adipose-derived factors abrogate the metastatic potential of CRC stem cells (CR-CSCs) in obese patients.
Quadruply-bonded dimolybdenum compounds: Reactivity towards TCNE. Structural evidences for the 1-D polymer [Mo2(O2 CCF3)4(TCNE)]∞
2005
cited By 3; International audience; Reaction of [Mo2(O2CR)4] (R = CF 3, 1) with TCNE in toluene affords the new compound [Mo2(O2CCF3)4 (TCNE)·6H5CH3 (2). The structure of 2 is built on [Mo2(O2 CCF3)4] fragments having the usual paddlewheel structure of 1 (Mo-Mo 2.1117(8) Å) and TCNE units. Each polynitrile moiety acts as a bridging ligand between two Mo2 fragments (Mo-N 2.875(4) Å) affording 1-D polymeric chains crossing in the crystal; the toluene molecules occupy the cavities between the chains. 13C NMR, IR and electrochemical data clearly show that formation of 2 does not involve electron density transfer from dimolybdenum fragment to the TCNE unit, which remains in 2 in its neutral stat…
The mechanism of formation of 3H,9H-Pyrano[3,4-b]indol-3-ones from 3-indolalkanoic acids
1991
The mechanism of the formation of 1-methyl-3H,9H-pyrano[3,4-b]indol-3-one (4) from the corresponding 3-indolacetic acid 1 is discussed. The suggested mechanism is substantiated by the isolation of a stable intermediate 2 and its transformations in the presence of acetic anhydride and/or Lewis acids.
A synthetic hexapeptide (Argireline) with antiwrinkle activity
2008
Botulinum neurotoxins (BoNTs) represent a revolution in cosmetic science because of their remarkable and long-lasting antiwrinkle activity. However, their high neurotoxicity seriously limits their use. Thus, there is a need to design and validate non-toxic molecules that mimic the action of BoNTs. The hexapeptide Ac-EEMQRR-NH2 (coined Argireline) was identified as a result of a rational design programme. Noteworthy, skin topography analysis of an oil/water (O/W) emulsion containing 10% of the hexapeptide on healthy women volunteers reduced wrinkle depth up to 30% upon 30 days treatment. Analysis of the mechanism of action showed that Argireline significantly inhibited neurotransmitter relea…
Reactions of α-diimino ligands with the chloro-bridged dimer [RhCl(COD)]2(COD=1,5-cyclooctadiene)
1988
Abstract The reactions of α-diimino ligands N - N ′ [ N - N ′= 2,2′-bipyridine (bipy), C 5 H 4 N2CHNR (R= C 6 H 4 OMe- p , PyCa), RNCHCHNR (R=C 6 H 4 - OMe- p , DAB)] with [RhCl(COD)] 2 give rise to stoichiometry, solvent, ligand, and temperature dependent equilibria. In general, the 1/1 ligand/dimer reaction yields the ionic product [Rh(COD)( N - N ′)] [RhCl 2 (COD)], at room temperature. For N - N ′=DAB, the ionic form is in equilibrium with the binuclear compound [{RhCl(COD)} (μ-DAB){RhCl(COD)}] (containing a σ σ,'- N , N ′ bridging α-diimine), which becomes the predominant species at low temperatures. In [Rh(COD)( N - N ′)] [RhCl 2 (COD)], a fast exchange of the Rh(COD) unit betwe…
Selective access to either a doubly boron-doped tetrabenzopentacene or an oxadiborepin from the same precursor
2019
Depending on the solvent, a brominated arylborane gave the multiple helicene B2-TBPA (pyridine) or the oxadiborepin ODBE (THF) after intramolecular Yamamoto coupling.
The enzymatic mechanism of epoxide hydrolysis
1995
Sequiterpene-related compounds as endocrine disrupters in Oncopeltus fasciatus, and potential reduced glutathione synthesis modifiers
1999
Sesquiterpene lactones have been found to exhibit effects on insect growth and development. In this study, the bioactivity of natural lactones extracted from Centaurea mariolensis and some structurally related synthetic derivatives has been investigated. Assays have also been carried out in order to determine the potential of these lactones as modifiers of reduced glutathione (GSH) synthesis.
The Catalytic Mechanism of Carboxylesterases: A Computational Study
2014
The catalytic mechanism of carboxylesterases (CEs, EC 3.1.1.1) is explored by computational means. CEs hydrolyze ester, amide, and carbamate bonds found in xenobiotics and endobiotics. They can also perform transesterification, a reaction important, for instance, in cholesterol homeostasis. The catalytic mechanisms with three different substrates (ester, thioester, and amide) have been established at the M06-2X/6-311++G**//B3LYP/6-31G* level of theory. It was found that the reactions proceed through a mechanism involving four steps instead of two as is generally proposed: (i) nucleophilic attack of serine to the substrate, forming the first tetrahedral intermediate, (ii) formation of the ac…