Search results for "choline"
showing 10 items of 1138 documents
Partition of Indicaxanthin in Membrane Biomimetic Systems. A Kinetic and Modeling Approach
2009
The solubilization site of indicaxanthin (Ind) in lipid bilayers was investigated by the kinetics of Ind oxidation by peroxyl radicals in water and in aqueous/L-alpha-dipalmitoyl-phosphatidylcholine (DPPC) vesicles, pH 7.4, and 37.0 and 48.0 degrees C, that is, in a gel-like and a crystal liquidlike bilayer state, respectively. The time-dependent Ind absorbance decay, matched with a successful simulation of the reaction kinetic mechanism by Gepasi software, supported a multistep pathway. Computer-assisted analysis allowed calculation of the rate constants associated with the reactions involved, the values of which decreased with increasing DPPC concentration. The binding constant calculated…
The influence of tin compounds on the dynamic properties of liposome membranes: A study using the ESR method
2005
AbstractThe influence of organic and inorganic compounds of tin on the dynamic properties of liposome membranes obtained in the process of dipalmitoylphosphatidylcholine (DPPC) sonication in distilled water was investigated. This was carried out by means of the spin ESR probe method. The probes were selected in such a way as to penetrate different areas of the membrane (a TEMPO probe, 5-DOXYL stearic acid, 16-DOXYL stearic acid). Four compounds of tin were chosen: three organic ones, (CH3)4Sn, (C2H5)4Sn and (C3H7)3SnCl, and one inorganic one, SnCl2. The investigated compounds were added to a liposome dispersion, which was prepared prior to that. The concentration of the admixture was change…
Glycerosomes: Use of hydrogenated soy phosphatidylcholine mixture and its effect on vesicle features and diclofenac skin penetration.
2016
In this work, diclofenac was encapsulated, as sodium salt, in glycerosomes containing 10, 20 or 30% of glycerol in the water phase with the aim to ameliorate its topical efficacy. Taking into account previous findings, glycerosome formulation was modified, in terms of economic suitability, using a cheap and commercially available mixture of hydrogenated soy phosphatidylcholine (P90H). P90H glycerosomes were spherical and multilamellar; photon correlation spectroscopy showed that obtained vesicles were ∼131nm, slightly larger and more polydispersed than those made with dipalmitoylphosphatidylcholine (DPPC) but, surprisingly, they were able to ameliorate the local delivery of diclofenac, whic…
Adenosine negatively regulates duodenal motility in mice: role of A1 and A2a receptors .
2011
Metabolic signatures across the full spectrum of non-alcoholic fatty liver disease.
2022
Funder: European Commission
1H NMR methodologies applied in the thermodynamic and structural characterization of organic supramolecular complexes
2021
Orientador: Anita Jocelyne Marsaioli Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química Resumo: Nesta tese consiste no estudo de interações supramoleculares utilizando diferentes metodologias de Ressonância Magnética Nuclear de hidrogênio (RMN de 1H), tais como ROESY 1D, RMN-DOSY e RMN-STD. Os sistemas supramoleculares foram abordados em dois casos de estudo diferentes. O Capítulo I tem como objeto de estudo interações do fármaco Dapsona com diferentes carreadores de fármacos (ß-CD, SBE-ß-CD e lipossoma de EPC), com a finalidade de encontrar formulações nas quais a Dapsona seja mais solúvel. Os complexos binários e ternário formados foram determinadas por medidas de …
Modulation by Scopolamine, Acetylcholine and Choline of the Evoked Release of Acetylcholine from the Guinea Pig Myenteric Plexus: Evidence for a Musc…
1981
There is evidence that the release of acetylcholine (ACh) from the guinea pig myenteric plexus is controlled via presynaptic muscarine receptors. Muscarinic antagonists such as atropine enhance the release evoked by either electrical field stimulation, by nicotinic drugs or by high K+ concentrations (4,7,10). On the other hand, the muscarinic agonist oxotremorine inhibits the evoked release of ACh (7). A comparable feedback inhibition has been described for the release of ACh from central cholinergic nerves (for review, see Ref. 12). However, it has so far not been shown whether the physiological transmitter itself is able to depress the release of neuronal ACh. We have, therefore, studied …
PRECURSOR CONTROL OF ACETYLCHOLINE SYNTHESIS AND RELEASE IN ISOLATED HEARTS ?
1980
Cardiovascular Outcomes of Cholinesterase Inhibitors in Individuals with Dementia: A Meta-Analysis and Systematic Review
2018
Objectives: To evaluate the cardiovascular (CV) effects of acetylcholinesterase inhibitors (AChEIs) in individuals with dementia. Design: Systematic review and meta-analysis. Setting: Two authors independently searched major electronic databases from inception until June 17, 2017, for longitudinal (without a control group) and cohort (with a control group) studies reporting CV outcomes in relation to AChEIs. Randomized controlled trials were excluded because they included relatively healthy subjects. Participants: Individuals with dementia and controls. Measurements: Changes in CV parameters were summarized using standardized mean differences (SMDs) with 95% confidence intervals (CIs). Even…
A fluorescence spectroscopy study of the interaction of monocationic quinine with phospholipid vesicles Effect of the ionic strength and lipid compos…
1997
Abstract The interaction of monocationic quinine with zwitterionic dimyristoyl phosphatidylcholine (DMPC) and mixed negatively-charged dimyristoylphosphatidyl glycerol (DMPG) DMPC small unilamellar vesicles in the liquid-crystalline phase was investigated by steady-state fluorescence spectroscopy at pH 7 and 37°C. The maximum fluorescence emission peak at 383 nm, upon excitation at 335 nm, shifts to lower wavelength and decreases its intensity as the ratio between the total lipid and quinine concentrations increases. This indicates that in the membrane-bound state quinine is in an environment of low polarity, more deeply buried when anionic DMPG is present in the vesicle. For monoprotonated…