Search results for "Cyclodextrin"
showing 10 items of 266 documents
Transmembrane form agrin-induced process formation requires lipid rafts and the activation of Fyn and MAPK.
2009
Overexpression or clustering of the transmembrane form of the extracellular matrix heparan sulfate proteoglycan agrin (TM-agrin) induces the formation of highly dynamic filopodia-like processes on axons and dendrites from central and peripheral nervous system-derived neurons. Here we show that the formation of these processes is paralleled by a partitioning of TM-agrin into lipid rafts, that lipid rafts and transmembrane-agrin colocalize on the processes, that extraction of lipid rafts with methyl-β-cyclodextrin leads to a dose-dependent reduction of process formation, that inhibition of lipid raft synthesis prevents process formation, and that the continuous presence of lipid rafts is requ…
On Complex Formation between 5-Fluorouracil and β-Cyclodextrin in Solution and in the Solid State: IR Markers and Detection of Short-Lived Complexes …
2020
In this work, the nuclear magnetic resonance (NMR) and IR spectroscopic markers of the complexation between 5-fluorouracil (5-FU) and &beta
Impact of 7-Ketocholesterol and Very Long Chain Fatty Acids on Oligodendrocyte Lipid Membrane Organization: Evaluation Via LAURDAN and FAMIS Spectral…
2011
International audience; In the context of multiple sclerosis and X-linked adrenoleukodystrophy, 7-ketocholesterol (7KC) and very long chain fatty acids (C24:0, C26:0) are supposed to induce side effects respectively on oligodendrocytes which are myelin (which is a lipoproteic complex) synthesizing cells. The effects of 7KC (25, 50 mu M), C24:0 and C26:0 (10, 20 mu M) on cell viability and lipid membrane organization were investigated on 158N murine oligodendrocytes. Concerning 7KC and fatty acids (at 20 mu M only):1) cell growth was strongly inhibited; 2) marked induction of cell death was revealed with propidium iodide (PI); 3) no apoptotic cells were found with C24:0 and C26:0 (absence of…
Inclusion complexes of triblock L35 copolymer and hydroxyl propyl cyclodextrins: a physico-chemical study
2022
In this work, we studied the formation of supramolecular inclusion complexes (pseudopolyrotaxanes) generated by the interactions between L35 Pluronic (PEO-PPO-PEO triblock copolymer) and hydroxyl propyl-modified cyclodextrins (HP-alpha-CD and HP-beta-CD). The structural characteristics of the L35/CD composites were investigated by X-ray diffraction spectroscopy, which highlighted the effective inclusion of the copolymer. The thermodynamic properties of the pseudopolyrotaxanes were determined through density and speed of sound experiments conducted on aqueous mixtures with various L35/CD compositions, while turbidimetric analyses allowed the investigation of the kinetics of the threading pro…
Hyaluronic acid and beta cyclodextrins films for the release of corneal epithelial cells and dexamethasone
2016
In this work we prepared hydrogels based on hyaluronic acid and β-cyclodextrins to sustain the release of both corneal epithelial cells and dexamethasone. This steroid is administered as eye drops several times per day to reduce the risk of rejection in the post operative period after the cornea transplantation and cell release techniques. Hydrogels were produced by crosslinking an amino derivative of hyaluronic acid, with the divinyl sulfone derivative of β-cyclodextrins, this last employed as a crosslinker and solubilizing agent. Drug release studies revealed that dexamethasone containing samples are able to extend the release of this drug for at least five days. Biological studies, condu…
Robust Mesoporous CoMo/γ-Al2O3 Catalysts from Cyclodextrin-Based Supramolecular Assemblies for Hydrothermal Processing of Microalgae: Effect of the P…
2018
Hydrothermal liquefaction (HTL) is a promising technology for the production of biocrude oil from microalgae. Although this catalyst-free technology is efficient under high-temperature and high-pressure conditions, the biocrude yield and quality can be further improved by using heterogeneous catalysts. The design of robust catalysts that preserve their performance under hydrothermal conditions will be therefore very important in the development of biorefinery technologies. In this work, we describe two different synthetic routes (i.e., impregnation and cyclodextrin-assisted one-pot colloidal approach), for the preparation in aqueous phase of six high surface area CoMo/γ-Al2O3 catalysts. Cat…
Multicavity halloysite-amphiphilic cyclodextrin hybrids for co-delivery of natural drugs into thyroid cancer cells
2015
Multicavity halloysite nanotube materials were employed as simultaneous carriers for two different natural drugs, silibinin and quercetin, at 6.1% and 2.2% drug loadings, respectively. The materials were obtained by grafting functionalized amphiphilic cyclodextrin onto the HNT external surface. The new materials were characterized by FT-IR spectroscopy, SEM, thermogravimetry, turbidimetry, dynamic light scattering and ζ-potential techniques. The interaction of the two molecules with the carrier was studied by HPLC measurements and fluorescence spectroscopy, respectively. The release of the drugs from HNT-amphiphilic cyclodextrin, at two different pH values, was also investigated by means of…
Copolymer−Cyclodextrin Inclusion Complexes in Water and in the Solid State. A Physico-Chemical Study
2008
The formation of inclusion complexes (ICs) composed of cyclodextrins (CDs) and poly(ethylene oxides)-poly(propylene oxides)-poly(ethylene oxides) (PEO-PPO-PEO) was studied. To this purpose, native and hydroxypropyl cyclodextrins with different cavity size were chosen. The PEO-PPO-PEO copolymers were selected to study the role of the molecular weight, keeping constant the hydrophilic/hydrophobic ratio, and the hydrophilicity. The volumetric studies at 25 degrees C allowed to determine the equilibrium constant and the volume change for the IC formation in water as well as the IC stoichiometry. Surface tension experiments evidenced that the copolymer and the CD interfacial behavior is controll…
Crystallinity of block copolymer controlled by cyclodextrin
2018
We report a differential scanning calorimetry study to investigate the effect of cyclodextrins (CD) on the crystallinity of a copolymer. Tetronics was selected as copolymer with star-like shape formed by four polyethylene oxide flanked by four polypropylene oxide blocks linked to ethylenediamine central group. The use of CD with different cavity size was exploited for a block selective inclusion. A model for supramolecular association was considered for a quantitative description of the enthalpy data. The polymer chain incorporation into the CD cavity generates a loss of crystallinity. The stoichiometry of the CD/copolymer aggregates can be tuned by changing the CD cavity size. The investig…
Optical Sensor for Real-Time Detection of Trichlorofluoromethane
2019
Trichlorofluoromethane was once a promising and versatile applicable chlorofluorocarbon. Unaware of its ozone-depleting character, for a long time it was globally applied as propellant and refrigerant and thus led to significant thinning of the ozone layer and contributed to the formation of the so-called ozone hole. Although production and application of this substance were gradually reduced at an early stage, we still face the consequences of its former careless use. Today, trichlorofluoromethane is released during recycling processes of waste cooling devices, traded on the black market, and according to recent findings still illegally manufactured. Here, we present an optical sensor devi…