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61.
Paulina Lewandowska Izabela Szczuka Iwona Bednarz-Misa Berenika M. Szczniak-Siga Katarzyna Neubauer Magdalena Mierzchaa-Pasierb Marek Zawadzki Wojciech Witkiewicz Magorzata Krzystek-Korpacka 《Molecules (Basel, Switzerland)》2021,26(23)
The mechanisms underlying the antineoplastic effects of oxicams have not been fully elucidated. We aimed to assess the effect of classic and novel oxicams on the expression/secretion of macrophage-associated chemokines (RTqPCR/Luminex xMAP) in colorectal adenocarcinoma cells, and on the expression of upstream the non-steroidal anti-inflammatory drug (NSAID)-activated genes NAG1, NFKBIA, MYD88, and RELA, as well as at the chemokine profiling in colorectal tumors. Meloxicam downregulated CCL4 9.9-fold, but otherwise the classic oxicams had a negligible/non-significant effect. Novel analogues with a thiazine ring substituted with arylpiperazine and benzoyl moieties significantly modulated chemokine expression to varying degree, upregulated NAG1 and NFKBIA, and downregulated MYD88. They inhibited CCL3 and CCL4, and their effect on CCL2 and CXCL2 depended on the dose and exposure. The propylene linker between thiazine and piperazine nitrogens and one arylpiperazine fluorine substituent characterized the most effective analogue. Only CCL19 and CXCL2 were not upregulated in tumors, nor was CXCL2 in tumor-adjacent tissue compared to normal mucosa. Compared to adjacent tissue, CCL4 and CXCL2 were upregulated, while CCL2, CCL8, and CCL19 were downregulated in tumors. Tumor CCL2 and CCL7 increased along with advancing T and CCL3, and CCL4 along with the N stage. The introduction of arylpiperazine and benzoyl moieties into the oxicam scaffold yields effective modulators of chemokine expression, which act by upregulating NAG1 and interfering with NF-κB signaling. 相似文献
62.
A. Roguska A. Kudelski M. Pisarek M. Lewandowska K.J. Kurzydowski M. Janik-Czachor 《Surface science》2009,603(17):77-2824
A tubular array of TiO2-nanotubes on a Ti substrate was used as a support for an Ag sputter-deposited layer intended for surface-enhanced Raman scattering (SERS) investigations. Composite samples of Ag/TiO2-nanotube/Ti were studied with the aid of scanning electron microscopy (SEM) and Auger electron spectroscopy (AES) to reveal their characteristic morphological and chemical features. Raman spectra of pyridine (as a probe molecule) were measured at different cathodic potentials ranging from −0.2 down to −1.2 V after the pyridine had been adsorbed on the TiO2-nanotube/Ti substrates covered with the Ag deposit. In addition, SERS spectra on a bulk electrochemically-roughened Ag reference substrate, were also measured.The SERS activity of the composite samples was strongly dependent on the amount of Ag deposit and, in some cases, was even higher than that for the Ag reference substrate. The SERS intensity vs. electrode potential dependences measured were interpreted in terms of the modified electronic structure of the Ag deposits due to the interaction of the Ag clusters with the TiO2-nanotube/Ti substrate. 相似文献
63.
J. Eid J.L. Santailler B. Ferrand A. Basset A. Passero R. Lewandowska C. Balloud J. Camassel 《Superlattices and Microstructures》2006,40(4-6):201
Cubic-silicon carbide crystals have been grown from carbon-rich silicon solutions using the travelling-zone method. To improve the growth process, we investigated the effect of controlling more tightly some of the growth parameters. Using such improved growth conditions, our best sample is a 12 mm diameter and 3 mm long 3C–SiC crystal. It is grown on a (0001) 2 off, 6H–SiC seed and has 111-orientation. The low amount of silicon inclusions results in a reduced internal stress, which is demonstrated by the consideration of μ-Raman spectra collected at room temperature on a large number of samples. 相似文献
64.
Dr. Agnieszka Janiak Prof. Dr. Urszula Rychlewska Dr. Marcin Kwit Urszula Stępień Dr. Krystyna Gawrońska Prof. Dr. Jacek Gawroński 《Chemphyschem》2012,13(6):1500-1506
Stereoisomers of one of the most important organic compounds, tartaric acid, optically active and meso as well as the ester or amide derivatives, can show diverse structures related to the rotation around the three carbon–carbon bonds. This study determines the controlling factors for conformational changes of these molecules in vacuo, in solution, and in the crystalline state using DFT calculations, spectroscopic measurements, and X‐ray diffraction. All structural variations can be logically accounted for by the possibility of formation and breaking of hydrogen bonds between the hydroxy or amide donors and oxygen acceptors, among these the hydrogen bonds that close five‐membered rings being the most stable. These findings are useful in designing molecular and crystal structures of highly polar, polyfunctional, chiral compounds. 相似文献
65.
Nazar Trotsko Jakub Krl Agata Siwek Monika Wujec Urszula Kosikowska Anna Malm 《Heteroatom Chemistry》2012,23(1):117-121
By the reaction of hydrazides of 4‐(4‐halogenophenyl)‐4H‐1,2,4‐triazol‐3‐yl‐sulfanyl acetic acid with isothiocyanate, 1‐acyl‐4‐substituted thiosemicarbazide derivatives ( 7–19 ) were obtained. The cyclization of compounds ( 7–19 ) in the presence of 2% NaOH led to the formation of compounds ( 20–26 ) containing two 1,2,4‐triazole rings connected by a methylenesulfanyl group. The new compounds were tested for their in vitro antimicrobial activity. Some of the tested compounds ( 9, 12, 18, 21, 22 ) showed activity against the reference strains of Gram‐positive bacteria with the MIC (minimal inhibitory concentration) = 125 to >1000 μg/mL. © 2011 Wiley Periodicals, Inc. Heteroatom Chem 23:117–121, 2012; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20758 相似文献
66.
Niko Guskos Spiros Glenis Janusz Typek Grzegorz Zolnierkiewicz Pawel Berczynski Kamil Wardal Aleksander Guskos Daniel Sibera Dariusz Moszyński Witold Lojkowski Urszula Narkiewicz 《Central European Journal of Physics》2012,10(2):470-477
Fine particles of ZnFe2O4 were synthesized by a wet chemical method in the (80 wt.% Fe2O3 + 20 wt.% ZnO) system. The morphological and structural properties of the mixed system were investigated by scanning electron microscopy, X-ray diffraction, inductively coupled plasma atomic emission, and X-ray photoelectron spectroscopy. The major phase was determined to be the ZnFe2O4 spinel with particle size of 11 nm. The magnetic properties of the material were investigated by ferromagnetic resonance (FMR) in the temperature range from liquid helium to room temperature. A very intense, asymmetric FMR signal from ZnFe2O4 nanoparticles was recorded, which has been analyzed in terms of two Callen-lineshape lines. Temperature dependence of the FMR parameters was obtained from fitting the experimental lines with two component lines. Analysis of the FMR spectra in terms of two separate components indicates the presence of strongly anisotropic magnetic interactions. 相似文献
67.
Tadeusz Kosztołowicz Katarzyna D. Lewandowska 《Central European Journal of Physics》2012,10(3):645-651
We consider here two different models describing subdiffusion. One of them is derived from Continuous Time Random Walk formalism
and utilizes a subdiffusion equation with a fractional time derivative. The second model is based on Sharma-Mittal nonadditive
entropy formalism where the subdiffusive process is described by a nonlinear equation with ordinary derivatives. Using these
two models we describe the process of a substance released from a thick membrane and we find functions which determine the
time evolution of the amount of substance remaining inside this membrane. We then find ‘the agreement conditions’ under which
these two models provide the same relation defining subdiffusion and give the same function characterizing the process of
the released substance. These agreement conditions enable us to determine the relation between the parameters occuring in
both models. 相似文献
68.
Andrzej Gzella Urszula Wrzeciono Wolfram Pppel 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(9):1161-1163
The structure analyses of racemic 3‐chloro‐1‐(4‐morpholino‐5‐nitroimidazol‐1‐yl)propan‐2‐ol, C10H15ClN4O4, (II), and 3‐chloro‐1‐(5‐morpholino‐4‐nitroimidazol‐1‐yl)propan‐2‐ol, C10H15ClN4O4, (III), have been undertaken in order to determine the position of the morpholine residue in these two isomers. The morpholine residue in (II) is connected at the 4‐position, while in (III), it is connected at the 5‐position of the imidazole ring. The morpholine mean planes and nitro groups in the two compounds deviate from the imidazole planes to different extents. The nitro groups in (II) and (III) take part in the conjugation system of the imidazole rings. In consequence, the exocyclic C—N bonds are significantly shorter than the normal single Csp2—NO2 bond and the nitro groups in (II) and (III) show an extraordinary stability on treatment with morpholine and piperidine [Gzella, Wrzeciono & Pöppel (1999). Acta Cryst. C 55 , 1562–1565]. In the crystal lattice, the molecules of both compounds are linked by O—H?N and C—H?O intermolecular hydrogen bonds. 相似文献
69.
Natalia Pachura Robert Kupczyski Kamila Lewandowska Maciej Wodarczyk Marta Klemens Piotr Kuropka Renata Nowaczyk Magorzata Krzystek-Korpacka Iwona Bednarz-Misa Tomasz Sozaski Krystyna Pogoda-Sewerniak Antoni Szumny 《Molecules (Basel, Switzerland)》2022,27(11)
Ilex paraguariensis, the holly tree, is a plant with recognized biological properties, whose aqueous infusions are known as “Yerba mate”, that regulate lipid metabolism, reduce obesity, and improve brain stimulation. In the present study, the effect of standardized saponin and terpenoid fractions of a European taxon, Ilex aquifolium, on blood biochemical parameters in a rat model of metabolic disorder, (fa/fa) Zucker, are presented. The profiles of the volatile fractions of two species and six European varieties of Ilex were investigated. After selecting the best variety, the saponin and terpenoid fractions were isolated and standardized, and animals were fed 10 mg kg−1 b.w. for 8 weeks. A statistically significant decrease in liver adiposity was observed, confirmed by histology and quantitative identification (gas chromatography–mass spectrometry analyses of hepatic lipids. RT-qPCR analysis of gene expression in the aorta revealed that the administration of the terpenoid fraction downregulated LOX-1, suggesting a reduction in atherosclerotic stimuli. In addition, a statistically significant reduction (p < 0.05) in PPARγ for the saponin fraction was observed in the liver. The expression of the ACAT-1 gene in the liver, responsible for the formation of cholesterol esters, increased significantly in the group receiving the terpenoid fraction compared to the control, which was also confirmed by the analysis of individual blood biochemical parameters. The opposite effect was observed for saponins. Taking the above into account, it is shown for the first time that Ilex aquifolium can be a source of compounds that positively influence lipid metabolism. 相似文献
70.
Dariusz Kiejza Urszula Kotowska Weronika Poliska Joanna Karpiska 《Molecules (Basel, Switzerland)》2022,27(15)
A new, simple and sensitive method for isolating nine compounds from the bisphenol group (analogues: A, B, C, E, F, G, Cl2, Z, AP) based on one-step liquid–liquid microextraction with in situ acylation followed by gas chromatography-mass spectrometry was developed and validated using influent and effluent wastewaters. The chemometric approach based on the Taguchi method was used to optimize the main conditions of simultaneous extraction and derivatization. The recoveries of the proposed procedure ranged from 85 to 122%, and the repeatability expressed by the coefficient of variation did not exceed 8%. The method’s limits of detection were in the range of 0.4–64 ng/L, and the method’s limits of quantification ranged from 1.3 to 194 ng/L. The developed method was used to determine the presence of the tested compounds in wastewater from a municipal wastewater treatment plant located in northeastern Poland. From this sample, eight analytes were detected. Concentrations of bisphenol A of 400 ng/L in influent and 100 ng/L in effluent were recorded, whereas other bisphenols reached 67 and 50 ng/L for influent and effluent, respectively. The removal efficiency of bisphenol analogues in the tested wastewater treatment plant ranged from 7 to approximately 88%. 相似文献