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191.
Hansel E. Gonzlez-Velasco María S. Prez-Gutirrez ngel J. Alonso-Castro Juan R. Zapata-Morales Perla del C. Nio-Moreno Nimsi Campos-Xolalpa Marco M. Gonzlez-Chvez 《Molecules (Basel, Switzerland)》2022,27(9)
Tagetes parryi is a plant empirically used to treat gastrointestinal and inflammatory diseases, its essential oil (EOTP) was obtained from the aerial parts, and the composition was elucidated by GC-MS. The in vivo and in vitro anti-inflammatory activities and the antinociceptive activity of EOTP and (1S)-(-)-verbenone (VERB) were assessed. The major compounds identified for EOTP were verbenone (33.39%), dihydrotagetone (26.88%), and tagetone (20.8%). EOTP and VERB diminished the ear oedema induced with TPA by 93.77 % and 81.13 %, respectively. EOTP and VERB decreased inflammation in a 12-O-tetradecanoylphorbol-13-acetate (TPA) chronic model with ED50 = 54.95 mg/kg and 45.24 mg/kg, respectively. EOTP (15 µg/mL) inhibited the in vitro production of the pro-inflammatory mediators NO (67.02%), TNF-α (69.21%), and IL-6 (58.44%) in LPS-stimulated macrophages. In the acetic induced writhing test, EOTP and VERB showed antinociceptive effects with ED50 = 84.93 mg/kg and ED50 = 45.24 mg/kg, respectively. In phase 1 of the formalin test, EOTP and VERB showed no antinociceptive effects, whereas in phase 2, EOTP (ED50 = 35.45 mg/kg) and VERB (ED50 = 24.84 mg/kg) showed antinociceptive effects. The antinociceptive actions of ETOP and VERB were blocked with the co-administration of L-NAME. This study suggests that EOTP and VERB might be used in the treatment of pain and inflammatory problems. 相似文献
192.
Inmaculada de Dios-Prez lvaro Gonzlez-Garcinuo Eva María Martín del Valle 《Molecules (Basel, Switzerland)》2022,27(9)
Isoprenoids are natural compounds essential for a great number of cellular functions. One of them is farnesol (FOH), which can reduce cell proliferation, but its low solubility in aqueous solvents limits its possible clinical use as a pharmacological tool. One alternative is the use of cyclodextrins (CDs) which house hydrophobic molecules forming inclusion complexes. To assess FOH potential application in anticancer treatments, Sulfobutylated β-cyclodextrin Sodium Salt (SBE-β-CD) was selected, due to it has high solubility, approbation by the FDA, and numerous studies that ensure its safety to be administered parenterally or orally without nephrotoxicity associated. The therapeutic action of farnesol and complex were studied in different carcinoma cells, compared with a normal cell line. Farnesol showed selectivity, affecting the viability of colon and liver cancer cells more than in breast cancer cells and fibroblasts. All cells suffered apoptosis after being treated with 150 μM of free FOH, but the complex reduced their cell viability between 50 and 75%. Similar results were obtained for both types of isomers, and the addition of phosphatidylcholine reverses this effect. Finally, cell cycle analysis corroborates the action of FOH as inducer of a G0/G1 phase; when the cells were treated using the complex form, this viability was reduced, reaching 50% in the case of colon and liver, 60% in fibroblasts, and only 75% in breast cancer. 相似文献
193.
聚合物作为一种有机发光材料,由于在平板显示和光电子器件中的良好应用前景而受到广泛研究[1~2].近年来,一个重要进展是在聚合物中观测到了受激发射(简称Poly-mer激光)现象[3~6].Polymer激光最早是在溶液中实现的[3~4].作为一种新型... 相似文献
194.
Raquel Muoz García Rodrigo Oliver-Simancas María Arvalo Villena Leticia Martínez-Lapuente Beln Ayestarn Lourdes Marchante-Cuevas María Consuelo Díaz-Maroto María Soledad Prez-Coello 《Molecules (Basel, Switzerland)》2022,27(9)
The objective of this study was to evaluate the effect of microwave treatment of crushed grapes on the yeast population of the must and on the development of alcoholic fermentation, as well as on the extraction of different compounds from the grapes such as polysaccharides and amino acids that can affect the organoleptic quality and stability of the wine. This study demonstrated for the first time the effect of the microwave treatment of grapes on native yeast species and their diversity, producing an increase in fermentation kinetics and a decrease in the lag phase. The microwave treatment produced a positive effect on the extraction of amino acids and polysaccharides from the grapes, resulting in significantly higher amounts of the main amino acids of the must and some major volatile compounds in the treated samples. The polysaccharides most affected by the microwave treatment were the PRAGs, the main polysaccharides liberated from grapes during the maceration. 相似文献
195.
Two titania photocatalysts have been prepared using the sol–gel method using TiCl4 as a precursor, and two different alcohols, namely, ethanol or propanol (Et or Pr). The main aim of this work was to study the effect of the nature of the alcohol on the chemical, structural and photocatalytic properties for paracetamol photodegradation of the final solids. The TiCl4/alcohol molar ratio to obtain the corresponding alkoxides (TiEt and TiPr) was 1/10. These alkoxides were calcined at 400 °C to prepare the oxide catalysts (named as TiEt400 and TiPr400). Powder X-ray diffraction (PXRD) of the original samples showed the presence of anatase diffraction peaks in sample TiPr, while TiEt is a completely amorphous material. Contrary to commercial TiO2-P25, the PXRD diagrams of the calcined samples showed anatase as the exclusive crystalline phase in both solids. The specific surface area (SBET) of sample TiPr400 was larger than that of sample TiEt400, and both larger than that of TiO2-P25. The three solids have been tested in the photodegradation of paracetamol in aqueous solution. It has been established that the alcohol used influences the properties and catalytic activity of the final oxides. The synthesized solids exhibit a higher activity than commercial TiO2-P25, because of their structural characteristics and larger SBET. 相似文献
196.
Juan I. Rodríguez 《Journal of computational chemistry》2013,34(8):681-686
An efficient method for computing the quantum theory of atoms in molecules (QTAIM) topology of the electron density (or other scalar field) is presented. A modified Newton–Raphson algorithm was implemented for finding the critical points (CP) of the electron density. Bond paths were constructed with the second‐order Runge–Kutta method. Vectorization of the present algorithm makes it to scale linearly with the system size. The parallel efficiency decreases with the number of processors (from 70% to 50%) with an average of 54%. The accuracy and performance of the method are demonstrated by computing the QTAIM topology of the electron density of a series of representative molecules. Our results show that our algorithm might allow to apply QTAIM analysis to large systems (carbon nanotubes, polymers, fullerenes) considered unreachable until now. © 2012 Wiley Periodicals, Inc. 相似文献
197.
E. Makrlík P. Toman P. Vaňura R. Rathore 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(2):775-779
In methods for quantification of 63Ni, in e.g. reactor coolant water, a chemical separation is required due to 63Ni being a pure beta emitter with limited means of quantification. 60Co, a common radionuclide in reactor coolant water, is not completely separated with the commonly used separation procedure, and it is not resolved from 63Ni in the beta spectrum. The separation method discussed in this work consists of TRU resin (Eichrom) and Ni resin (Eichrom). After running the separation procedure, depending on the initial activity of 60Co, there may still remain enough 60Co to interfere in the measurement of 63Ni. The 60Co interference is corrected for via a gamma spectrometric measurement. This correction may, depending on the 63Ni/60Co ratio, introduce a large contribution to the measurement uncertainty. The aim of this work was to evaluate the possibility to reduce the measurement uncertainty of 63Ni measurements by adding a second Ni separation to the method. Double Ni separations were performed on reactor coolant water having a 60Co activity much higher than the 63Ni activity (63Ni/60Co = 0.01), in order to decrease the radioactivity of 60Co in the sample. The measurement uncertainty of the 63Ni measurement result was reduced by a factor of about three. 相似文献
198.
Today, the technology of microencapsulation of active principles is on top of biomedical advances, because through it we can solve many of the problems caused by current methods of taking medication. Active principle microencapsulation not only solves the problems of drug intake but also controls its dosage. In this study was carried out the development of a protocol for the microencapsulation of ibuprofen by solvent evaporation method. A subsequent application of those microencapsulates to biofunctional textile substrates (cotton, polyamide, acrylic, and polyester) using a finishing process, and finally a study of the release of active principle in two different media (deionized water and physiological serum) has been carried out using samples of the treated fabrics that were submerged into a thermostatized vessel at semi-infinite bath conditions. The determination of active principles released to the bath was determined by a UV spectrophotometer. These experimental results have been analyzed and evaluated, and have therefore allowed to define a controlled drug release system by Fickian diffusion in different media. 相似文献
199.
Youness Ouahid María C. Zaccaro Gloria Zulpa Mónica Storni Ana M. Stella Juan C. Bossio 《International journal of environmental analytical chemistry》2013,93(6):525-536
Microcystis is one of the most common bloom-forming cyanobacteria genera in diverse ecosystems. More than 80% of its strains are toxic, mainly due to their ability to produce metabolites known as microcystins (MC). Here we report on a M. aeruginosa bloom that appeared in the summer of 2001 at a site of the Río de la Plata, within the city of Buenos Aires. The symptoms in mice indicated that the bloom was hepatotoxic. LC-PDA analysis revealed a similar high concentration (0.9–1?mg?g–1?d w) of just one MC in the bloom biomass during the 3-month study period. During this period most of the MC (ca. 98 %) was found intracellularly, and the content remained almost the same. The molecular mass of the bloom MC was 1036?Da, as deduced from LC-ESI-MS data. Fragment ion analysis by LC-IT-MS-MS allowed identifying 6 out of the 7 amino acids, as well as their position in the molecule. The molecular mass of the unidentified amino acid residue was 155?Da. According to the data obtained, the MC under study was MC-XR, X representing the unidentified amino acid. This is the first report both on the characterisation of MCs in an urban site of the Río de la Plata waters, and on an Argentinean bloom exhibiting only one MC variant. 相似文献
200.
Es wurde eine Laboreinrichtung zur kontiniuerlichen Aktivierungsanalyse strömender, Flüssigkeiten entworfen und gebaut. Die Einrichtung bestecht aus dem Vorratsbehälter für die Probelösung, der Aktivierungskammer, einer Pu-Be-Neutronenquelle, der Meβkammer, der Meβeinrichtung, einer Laborpumpe und einem Strömungsmesser. Die vorläufigen Versuche bewiesen, daβ mit der gebauten Einrichtung die Bestimmung von Vanadium, Silber and Kobalt möglich ist. 相似文献