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Methyl cyclodextrin

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https://www.readbyqxmd.com/read/28432770/chiral-separation-of-aryloxyphenoxy-propionate-herbicides-in-a-permethyl-%C3%AE-cyclodextrin-based-column-influence-of-temperature-and-mobile-phase-composition-on-enantioselectivity
#1
Ester Lubomirsky, Héctor Di Loreto, Juan M Padró, Cecilia B Castells
We used a permethyl-β-cyclodextrin chiral stationary phase under reversed-phase conditions for the chiral separation of four aryloxyphenoxy-propionate herbicides (fenoxaprop-p-ethyl, quizalofop-p-ethyl and tefuryl and haloxyfop-p-methyl) with mixtures of methanol, ethanol, 2-propanol, n-propanol, tert-butanol, or acetonitrile and water as mobile phases and investigated the influence of mobile phase composition and column temperature (from 0 to 50 °C) on the separation. The retention factors (k) and selectivity factors (α) of all the herbicides investigated decreased with increasing temperature...
April 22, 2017: Electrophoresis
https://www.readbyqxmd.com/read/28423596/transient-activation-of-the-pi3k-akt-pathway-promotes-newcastle-disease-virus-replication-and-enhances-anti-apoptotic-signaling-responses
#2
Yinfeng Kang, Runyu Yuan, Xiaqiong Zhao, Bin Xiang, Shimin Gao, Pei Gao, Xu Dai, Minsha Feng, Yanling Li, Peng Xie, Yulian Li, Xiaoyi Gao, Tao Ren
Viral infection activates a host's cellular phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway, which is involved in cell differentiation, growth, survival, and apoptosis. To elucidate molecular mechanisms in the pathogenesis of Newcastle disease virus (NDV), we demonstrated that NDV transiently activates the PI3K/Akt pathway in chicken cells at an early phase of infection. Its activation was observed as early as 15 min post-infection and gradually weakened after 24 h. Incubating cells with a PI3K inhibitor, LY294002 or wortmannin, prior to NDV infection decreased NDV progeny yields and suppressed Akt phosphorylation at early times post-infection...
April 4, 2017: Oncotarget
https://www.readbyqxmd.com/read/28421241/effect-of-methyl-%C3%AE-cyclodextrin-on-gene-expression-in-microbial-conversion-of-phytosterol
#3
Victoria Y Shtratnikova, Mikhail I Schelkunov, Dmitry V Dovbnya, Eugeny Y Bragin, Marina V Donova
Modified β-cyclodextrins are widely used for the enhancement of microbial conversions of lipophilic compounds such as steroids. Multiple mechanisms of cyclodextrin-mediated enhancement of phytosterol bioconversion by mycobacteria had previously been shown to include steroid solubilization, alterations in the cell wall permeability for both steroids and nutrients, facilitation of protein leaking, and activity suppression of some steroid-transforming enzymes.In this work, we studied whether cyclodextrins might affect expression of the genes involved in the steroid catabolic pathway...
April 18, 2017: Applied Microbiology and Biotechnology
https://www.readbyqxmd.com/read/28412819/d-%C3%AE-tocopheryl-polyethylene-glycol-succinate-micelles-structure-kinetic-pathways-and-modulation-by-cyclodextrins
#4
Joan Puig-Rigall, Isabelle Grillo, Cecile A Dreiss, Gustavo González-Gaitano
The aggregation and structure of D-α-tocopheryl polyethylene glycol succinate micelles, TPGS-1000, an amphiphilic derivative of vitamin E, were characterized by scattering and spectroscopic methods, and the impact of different cyclodextrins (CDs) on the self-assembly studied, with the view of combining these two versatile pharmaceutical excipients in drug formulations. Combined SANS, DLS, time-resolved and steady-state fluorescence emission experiments revealed a core-shell architecture with a high aggregation number (Nagg ~ 100) and a highly hydrated PEO corona (~ 11 molecules of solvent per EO unit)...
April 16, 2017: Langmuir: the ACS Journal of Surfaces and Colloids
https://www.readbyqxmd.com/read/28411453/inhibition-of-influenza-virus-infection-by-multivalent-pentacyclic-triterpene-functionalized-per-o-methylated-cyclodextrin-conjugates
#5
Zhenyu Tian, Longlong Si, Kun Meng, Xiaoshu Zhou, Yongmin Zhang, Demin Zhou, Sulong Xiao
Multivalent ligands that exhibit high binding affinity to influenza hemagglutinin (HA) trimer can block the interaction of HA with its sialic acid receptor. In this study, a series of multivalent pentacyclic triterpene-functionalized per-O-methylated cyclodextrin (CD) derivatives were designed and synthesized using 1, 3-dipolar cycloaddition click reaction. A cell-based assay showed that three compounds (25, 28 and 31) exhibited strong inhibitory activity against influenza A/WSN/33 (H1N1) virus. Compound 28 showed the most potent anti-influenza activity with IC50 of 4...
April 2, 2017: European Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28406307/gamma-cyclodextrin-as-a-catalyst-for-the-synthesis-of-2-methyl-3-5-diarylisoxazolidines-in-water
#6
Giuseppe Floresta, Carmen Talotta, Carmine Gaeta, Margherita De Rosa, Ugo Chiacchio, Placido Neri, Antonio Rescifina
A green and efficient 1,3-dipolar cycloaddition of nitrones with different styrenes and cinnamates using a catalytic amount of gamma-cyclodextrin (γ-CD) in water has been developed to give substituted isoxazolidines. γ-CD was found to be highly efficacious in carrying out this reaction under eco-friendly environment affording moderate to excellent yields and in some case excellent diastereomeric excess (up to >95%) at 100 °C in 8-12 h. The catalyst can be easily recuperated and recycled for several times without loss of activity...
April 13, 2017: Journal of Organic Chemistry
https://www.readbyqxmd.com/read/28394556/%C3%AE-cd-functionalized-microdevice-for-rapid-capture-and-release-of-bacteria
#7
Alexandra Perez-Anes, Anna Szarpak-Jankowska, Dorothée Jary, Rachel Auzely-Velty
Most procedures for detecting pathogens in liquid media require an initial concentration step. In this regard, carbohydrates have proven to be attractive affinity ligands for the solid-phase capture of bacteria that use lectins for adhesion to host cell membranes. However, the use of cyclodextrin-immobilized substrates to selectively trap bacteria has not been explored before. Here, using quartz-crystal microbalance with dissipation monitoring experiments, we demonstrate that functionalization of surfaces by β-cyclodextrin (β-CD) can not only allow for rapid and efficient capture of bacterial cells in liquid but also their facile elution with an aqueous solution of a selectively methylated β-CD derivative as a competitive molecule...
April 10, 2017: ACS Applied Materials & Interfaces
https://www.readbyqxmd.com/read/28388069/detection-and-removal-of-endogenous-carbon-monoxide-by-selective-and-cell-permeable-hemoprotein-model-complexes
#8
Saika Minegishi, Aki Yumura, Hirotsuna Miyoshi, Shigeru Negi, Shigeru Taketani, Roberto Motterlini, Roberta Foresti, Koji Kano, Hiroaki Kitagishi
Carbon monoxide (CO) is produced in mammalian cells during heme metabolism and serves as an important signaling messenger. Here we report the bioactive properties of selective CO scavengers, hemoCD1 and its derivative R8-hemoCD1, which have the ability to detect and remove endogenous CO in cells. HemoCD1 is a supramolecular hemoprotein-model complex composed of 5,10,15,20-tetrakis(4-sulfonatophenyl)porphinatoiron(II) and a per-O-methylated β-cyclodextrin dimer having an pyridine linker. We demonstrate that hemoCD1 can be used effectively to quantify endogenous CO in cell lysates by a simple spectrophotometric method...
April 7, 2017: Journal of the American Chemical Society
https://www.readbyqxmd.com/read/28384320/direct-administration-of-2-hydroxypropyl-beta-cyclodextrin-into-guinea-pig-cochleae-effects-on-physiological-and-histological-measurements
#9
J T Lichtenhan, K Hirose, C A Buchman, R K Duncan, A N Salt
2-Hydroxypropyl-Beta-Cyclodextrin (HPβCD) can be used to treat Niemann-Pick type C disease, Alzheimer's disease, and atherosclerosis. But, a consequence is that HPβCD can cause hearing loss. HPβCD was recently found to be toxic to outer hair cells (OHCs) in the organ of Corti. Previous studies on the chronic effects of in vivo HPβCD toxicity did not know the intra-cochlear concentration of HPβCD and attributed variable effects on OHCs to indirect drug delivery to the cochlea. We studied the acute effects of known HPβCD concentrations administered directly into intact guinea pig cochleae...
2017: PloS One
https://www.readbyqxmd.com/read/28381673/iron-ii-porphyrin-cyclodextrin-supramolecular-complex-as-a-carbon-monoxide-depleting-agent-in-living-organisms
#10
REVIEW
Hiroaki Kitagishi, Saika Minegishi
The specific intermolecular interaction between an anionic tetraarylporphyrin and per-O-methylated β-cyclodextrin (TMe-β-CD) paved the way to produce a functional supramolecule that works as a strong carbon monoxide (CO)-depleting agent in living organisms. The supramolecular complex, hemoCD, that is composed of meso-tetrakis(4-sulfonatophenyl)porphinatoiron(II) and a TMe-β-CD dimer linked by a pyridine linker, captured internal CO from carboxyhemoglobin during its circulation in the blood of animals. HemoCD thus produced the pseudo-knockdown (loss-of-functional) state of endogenous CO in the animals...
2017: Chemical & Pharmaceutical Bulletin
https://www.readbyqxmd.com/read/28378327/characterization-of-a-single-isomer-carboxymethyl-beta-cyclodextrin-in-chiral-capillary-electrophoresis
#11
Ida Fejős, Erzsébet Varga, Gábor Benkovics, Milo Malanga, Tamás Sohajda, Julianna Szemán, Szabolcs Beni, Szabolcs Béni
In this work, the synthesis, characterization and chiral capillary electrophoretic study of heptakis-(2,3-di-O-methyl-6-O-carboxymethyl)-β-cyclodextrin (HDMCM), a single-isomer carboxymethylated cyclodextrin are presented. The pH-dependent and selector concentration-dependent enantiorecognition properties of HDMCM were investigated and discussed herein. The enantioseparation was assessed applying a structurally diverse set of non-charged, basic, and zwitterionic racemates. The increase in the selector concentration and in the gross negative charge of HDMCM improved the enantioseparation that could be observed in the majority of the cases...
April 5, 2017: Electrophoresis
https://www.readbyqxmd.com/read/28366805/probing-the-dynamics-of-complexed-local-anesthetics-via-neutron-scattering-spectroscopy-and-dft-calculations
#12
Murillo L Martins, Juergen Eckert, Henrik Jacobsen, Éverton C Dos Santos, Rosanna Ignazzi, Daniele Ribeiro de Araujo, Marie-Claire Bellissent-Funel, Francesca Natali, Michael Marek Koza, Aleksander Matic, Eneida de Paula, Heloisa N Bordallo
Since potential changes in the dynamics and mobility of drugs upon complexation for delivery may affect their ultimate efficacy, we have investigated the dynamics of two local anesthetic molecules, bupivacaine (BVC, C18H28N2O) and ropivacaine (RVC, C17H26N2O), in both their crystalline forms and complexed with water-soluble oligosaccharide 2-hydroxypropyl-β-cyclodextrin (HP-β-CD). The study was carried out by neutron scattering spectroscopy, along with thermal analysis, and density functional theory computation...
March 31, 2017: International Journal of Pharmaceutics
https://www.readbyqxmd.com/read/28359893/spectroscopic-studies-on-the-gemini-surfactant-mediated-refolding-of-human-serum-albumin
#13
Nuzhat Gull, Javed Masood Khan, Rukhsana, Rizwan Hassan Khan
Refolding of guanidinium hydrochloride (GdCl) denatured human serum albumin (HSA) using a combination of cationic gemini surfactants; pentanediyl-α,ω-bis(cetyldimethylammonium bromide) (C16H33(CH3)2N(+)-(CH2)5-N(+)(CH3)2C16H33)2Br(-) designated as G5 and methyl- β-cyclodextrin, is attempted in the present study. The studies were carried out in an aqueous medium (pH 7.4) using dynamic light scattering (DLS), circular dichroism (CD) and fluorescence spectroscopy. A careful study of the DLS data indicates that against the hydrodynamic radius (Rh) of 3...
March 27, 2017: International Journal of Biological Macromolecules
https://www.readbyqxmd.com/read/28359224/evaluation-of-porphyrin-loaded-dry-alginate-foams-containing-poloxamer-407-and-%C3%AE-cyclodextrin-derivatives-intended-for-wound-treatment
#14
Victoria J Valerón Bergh, Elin Johannessen, Therese Andersen, Hanne Hjorth Tønnesen
Dry alginate foams intended for antibacterial photodynamic therapy (aPDT) of infected wounds were prepared. aPDT is a treatment modality involving light of appropriate wavelength, oxygen and a photosensitizer (PS) to produce radicals that attack biological targets (e.g. bacteria). The hydrophobic 5, 10, 15, 20-tetrakis(4-hydroxyphenyl)porphyrin (THPP) was chosen as a model PS and loaded into the foams. The foams contained a poloxamer (Pluronic F127) and/or β-cyclodextrin (βCD)-derivatives, i.e. methylβCD (MβCD), heptakis(2,6-di-O-methyl)-βCD (HkβCD) or hydroxypropylβCD (HPβCD)...
March 31, 2017: Pharmaceutical Development and Technology
https://www.readbyqxmd.com/read/28350088/reactive-oxygen-species-mediate-angiotensin-ii-induced-transcytosis-of-low-density-lipoprotein-across-endothelial-cells
#15
Fang Bian, Jun Cui, Tao Zheng, Si Jin
The retention of plasma low-density lipoprotein (LDL) particles to subendothelial spaces through transcytosis across the endothelium is the initial step of atherosclerosis (AS). Angiotensin II (Ang II), as the principal effector molecule of the renin-angiotensin system (RAS), is implicated in several important steps of AS development. However, whether or not Ang II can directly exert a pro‑atherogenic effect by promoting LDL transcytosis across endothelial barriers, has not been defined. In the present study, we found that Ang II upregulated intracellular reactive oxygen species (ROS) levels in endothelial cells (ECs) by measuring fluorescence of 2',7'-dichlorofluorescein (DCF‑DA)...
February 13, 2017: International Journal of Molecular Medicine
https://www.readbyqxmd.com/read/28344495/enantioselective-analysis-of-fluoxetine-in-pharmaceutical-formulations-by-capillary-zone-electrophoresis
#16
Melania Cârcu-Dobrin, Monica Budău, Gabriel Hancu, Laszlo Gagyi, Aura Rusu, Hajnal Kelemen
Fluoxetine is an antidepressant, a selective serotonin reuptake inhibitor (SSRI) used primarily in the treatment of major depression, panic disorder and obsessive compulsive disorder. Chiral separation of racemic fluoxetine is necessary due to its enantioselective metabolism. In order to develop a suitable method for chiral separation of fluoxetine, cyclodextrin (CD) modified capillary electrophoresis (CE) was employed. A large number of native and derivatized, neutral and ionized CD derivatives were screened to find the optimal chiral selector...
March 2017: Saudi Pharmaceutical Journal: SPJ: the Official Publication of the Saudi Pharmaceutical Society
https://www.readbyqxmd.com/read/28341986/enhancing-effectiveness-of-capillary-electrophoresis-as-an-analytical-tool-in-the-supramolecular-acidity-modification
#17
Paweł Mateusz Nowak, Michał Woźniakiewicz, Magdalena Janus, Paweł Kościelniak
A strategic modification of acidity (pK a values) by the non-covalent host-guest interactions is one of the most promising concepts in current supramolecular chemistry. This work is aimed at enhancing the effectiveness of capillary electrophoresis (CE) in determination of pK a shifts caused by such interactions and their thermal dependencies crucial in a deep thermodynamic description. We show how to (i) minimize the systematic errors related to Joule heating, (ii) minimize the influence of a voltage ramp time, (iii) speed up pK a shift identification and estimation, (iv) interpret thermal effects related to two overlapped dynamic equilibria, and (v) determine pK a shifts by an alternative spectrophotometric method (CE-DAD)...
March 24, 2017: Analytical and Bioanalytical Chemistry
https://www.readbyqxmd.com/read/28340784/separation-of-20-coumarin-derivatives-using-the-capillary-electrophoresis-method-optimized-by-a-series-of-doehlert-experimental-designs
#18
Michał Woźniakiewicz, Marta Gładysz, Paweł M Nowak, Justyna Kędzior, Paweł Kościelniak
The aim of this study was to develop the first CE-based method enabling separation of 20 structurally similar coumarin derivatives. To facilitate method optimization a series of three consequent Doehlert experimental designs with the response surface methodology was employed, using number of peaks and the adjusted time of analysis as the selected responses. Initially, three variables were examined: buffer pH, ionic strength and temperature (No. 1 Doehlert design). The optimal conditions provided only partial separation, on that account, several buffer additives were examined at the next step: organic cosolvents and cyclodextrin (No...
May 15, 2017: Talanta
https://www.readbyqxmd.com/read/28328068/separation-of-enilconazole-enantiomers-in-capillary-electrophoresis-with-cyclodextrin-type-chiral-selectors-and-investigation-of-structure-of-selector-selectand-complexes-by-using-nuclear-magnetic-resonance-spectroscopy
#19
Ann Gogolashvili, Elene Tatunashvili, Lali Chankvetadze, Tamas Sohajda, Julianna Szeman, Antonio Salgado, Bezhan Chankvetadze
In the present study, the enantiomer migration order (EMO) of enilconazole in the presence of various cyclodextrins (CDs) was investigated by capillary electrophoresis (CE). Opposite EMO of enilconazole were observed when β-CD or the sulfated heptakis(2-O-methyl-3,6-di-O-sulfo)-β-CD (HMDS-β-CD) was used as the chiral selectors. Nuclear magnetic resonance (NMR) spectroscopy was used to study the mechanism of chiral recognition between enilconazole enantiomers and those two cyclodextrins. On the basis of rotating frame nuclear Overhauser (ROESY) experiments, the structure of an inclusion complex between enilconazole and β-CD was derived, in which (+)-enilconazole seemed to form a tighter complex than the (-)-enantiomer...
March 22, 2017: Electrophoresis
https://www.readbyqxmd.com/read/28327344/direct-activation-of-ca-2-and-voltage-gated-potassium-channels-of-large-conductance-by-anandamide-in-endothelial-cells-does-not-support-the-presence-of-endothelial-atypical-cannabinoid-receptor
#20
Alexander I Bondarenko, Olga Panasiuk, Iryna Okhai, Fabrizio Montecucco, Karim J Brandt, Francois Mach
Endocannabinoid anandamide induces endothelium-dependent relaxation commonly attributed to stimulation of the G-protein coupled endothelial anandamide receptor. The study addressed the receptor-independent effect of anandamide on large conductance Ca(2+)-dependent K(+) channels expressed in endothelial cell line EA.hy926. Under resting conditions, 10µM anandamide did not significantly influence the resting membrane potential. In a Ca(2+)-free solution the cells were depolarized by ~10mV. Further administration of 10µM anandamide hyperpolarized the cells by ~8mV...
March 19, 2017: European Journal of Pharmacology
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