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51.
Richard K. Haynes Burkhard Fugmann Jrg Stetter Karl Rieckmann Hans‐Dietrich Heilmann Ho‐Wai Chan Man‐Ki Cheung Wai‐Lun Lam Ho‐Ning Wong Simon L. Croft Livia Vivas Lauren Rattray Lindsay Stewart Wallace Peters Brian L. Robinson Michael D. Edstein Barbara Kotecka Dennis E. Kyle Bernhard Beckermann Michael Gerisch Martin Radtke Gabriele Schmuck Wolfram Steinke Ute Wollborn Karl Schmeer Axel Rmer 《Angewandte Chemie (International ed. in English)》2006,45(13):1989-1989
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Maria Cristina Marcucci Carlos Rocha Oliveira Daniel Spindola Alyne A. Antunes Leila Y. K. Santana Victor Cavalaro Isabelle B. Costa Ana C. de Carvalho Thiago A. M. Veiga Livia S. Medeiros Lucas dos Santos Zamarioli Carolina P. Gonalves Milena F. Santos Simone S. Grecco Vanessa Y. Suzuki Lydia Masako Ferreira Daniel M. Garcia 《Molecules (Basel, Switzerland)》2022,27(17)
The aim of this study was to investigate the cytotoxic activity of the Coriandrum sativum (C. sativum) ethanolic extract (CSEE) in neuroblastoma cells, chemically characterize the compounds present in the CSEE, and predict the molecular interactions and properties of ADME. Thus, after obtaining the CSEE and performing its chemical characterization through dereplication methods using UPLC/DAD-ESI/HRMS/MS, PM6 methods and the SwissADME drug design platform were used in order to predict molecular interactions and ADME properties. The CSEE was tested for 24 h in neuroblastoma cells to the establishment of the IC50 dose. Then, the cell death was evaluated, using annexin-PI, as well as the activity of the effector caspase 3, and the protein and mRNA levels of Bax and Bcl-2 were analyzed by ELISA and RT-PCR, respectively. By UHPLC/DAD/HRMS-MS/MS analysis, the CSEE showed a high content of isocoumarins-dihydrocoriandrin, coriandrin, and coriandrones A and B, as well as nitrogenated compounds (adenine, adenosine, and tryptophan). Flavonoids (apigenin, hyperoside, and rutin), phospholipids (PAF C-16 and LysoPC (16:0)), and acylglicerol were also identified in lower amount as important compounds with antioxidant activity. The in silico approach results showed that the compounds 1 to 6, which are found mostly in the C. sativum extract, obey the “Five Rules” of Lipinski, suggesting a good pharmacokinetic activity of these compounds when administered orally. The IC50 dose of CSEE (20 µg/mL) inhibited cell proliferation and promoted cell death by the accumulation of cleaved caspase-3 and the externalization of phosphatidylserine. Furthermore, CSEE decreased Bcl-2 and increased Bax, both protein and mRNA levels, suggesting an apoptotic mechanism. CSEE presents cytotoxic effects, promoting cell death. In addition to the promising results predicted through the in silico approach for all compounds, the compound 6 showed the best results in relation to stability due to its GAP value. 相似文献
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Jardim IC Maldaner L Lourenço J Fioravanti LM Collins CH 《Journal of separation science》2010,33(19):2917-2929
At the present time, more complex analyses of apolar compounds with similar chemical structures or of polar compounds, especially basic ones, having diverse properties require more selective stationary phases having better stabilities. This paper describes several new stationary phases with directed selectivities that were prepared by immobilizing two different phenyl group-containing siloxanes and a trifluoropropyl-containing siloxane onto chromatographic silica and, in the case of the fluorinated siloxane, onto zirconized silica, using thermal treatment or microware radiation. The chromatographic properties and stabilities of these new phases were determined and several applications were evaluated. The phenyl-containing phases showed excellent characteristics related to the separation of several different types of aromatic compounds while the fluorinated phases, which present a more polar character, revealed selectivity for the separation of positional isomers as well as for a mixture of basic pharmaceuticals. Stability tests indicate that immobilization of the polysiloxanes increases column lifetimes by making the stationary phases less susceptible to dissolution, while the phases immobilized with microwave radiation were somewhat more stable than those immobilized by thermal treatments. 相似文献
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Eugen A. Preoteasa Elena Preoteasa Livia Harangus Antoniu Moldovan Maria Dinescu Dieter Grambole Folker Herrmann 《X射线光谱测定》2010,39(3):208-215
We applied proton microbeam particle‐induced X‐ray emission (µ‐PIXE) for mapping Ca, Zr, Ba and Yb, and atomic force microscopy (AFM) for imaging the surface landscape of a dental composite which releases Ca2+ and F? for the protection of hard dental tissues. Three areas ~250 × 250 µm2 located ~0.5–2 mm apart on a smooth surface specimen were mapped with 3.1 MeV protons focused to a ~3.0 µm spot and at ~3.9 µm pixel size sampling. The maps evidenced particles with diameters of 3.2–32 µm (Ca), 20–60 µm (Zr), ≤ 4 µm (Ba) and 10–50 µm (Yb). Cross‐section area histograms of Ca‐rich particles fitted with 2–6 Poisson functions revealed a polydisperse size distribution and substantial differences from an area to another, possibly implying large local variations of Ca2+ released in the hard tissue near a dental filling of a few millimeters in diameter. Such imbalances may lead to low local Ca2+ protection of the dental tissue, favoring the onset of secondary caries. Similarly, AFM images showed high zone‐dependent differences in the distributions of grains with apparent diameters of 1–4 µm, plausibly recognized as Ca‐ and Ba‐containing particles. In a simple model based on demineralization data, lateral diffusion of Ca2+ between adjacent domains containing high‐ and low‐area Ca‐rich grains is described by exponential concentration gradients. These gradients may generate appreciable electromotive forces, which may enhance electrochemically the local tissue demineralization. Similar effects are to be expected in the protective action of F? ions released from microgranules of YbF3 and of Ba fluoroaluminosilicate glass. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Acta Applicandae Mathematicae - We describe some recent results on existence of quasi-periodic solutions of Hamiltonian PDEs on compact manifolds. We prove a linear stability result for the... 相似文献
58.
The n-butyl amine TPD measurement of Brönsted acidity for solid catalysts by simultaneous TG/DTG-DTA
The method for Brönsted acidity measurement based on TPD of alkyl amines desorption by gas-chromatography or thermogravimetry was adapted for simultaneous TG/DTG-DTA analysis. The acidity measurements were focused on the 12-tungstophosphoric acid (H3PW12O40) and its salts, especially with Cesium since these posses the highest Brönsted acidity and they are among the most interesting catalysts. The n-butyl amine (NBA) desorption takes place in three steps for CsxH3−xPW12O40, x = 0-2, and four steps for the Cs2.5H0.5PW12O40. The steps of desorption correspond to the release of NBA molecules in stages, as NBA or butene molecules resulted from the Hofmann elimination reaction and NH3 + H2O formed by decomposition of ammonium salt. The quantities of desorption products, C4H8 and NH3 + H2O, corresponding to the stages with the maximum desorption rates at 400-420 °C, respectively 560-600 °C, are in the stoichiometric ratio with the Brönsted acidity. 相似文献
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Lorena Martínez Livia Arizaga Donatella Armentano Francesc Lloret Ricardo González Carlos Kremer 《Journal of Coordination Chemistry》2018,71(6):748-762
AbstractTwo new mixed-valence iron complexes with 2-pyridyl oximes, [Fe(mpko)3Fe(H2O)2(NO3)](NO3)·2H2O (1) (mpko? = methyl(2-pyridyl)ketone oximate) and [{Fe(dpko)3}2Fe](ClO4)·4H2O (2) (dpko? = bis(2-pyridyl)ketone oximate), have been prepared by reaction of FeIII with mpkoH in methanol (1) and FeII with dpkoH in methanol/water (2). Dinuclear FeII(low-spin)FeIII(high-spin) and trinuclear FeII(low-spin)FeIII(high-spin)FeII(low-spin) cations are present in the crystal structure of 1 and 2, respectively. Intermolecular hydrogen bonds in 1 lead to weak antiferromagnetic interactions between pairs of neighboring FeIII centers, which allows observation of single-ion zero-field splitting effects. 相似文献