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51.
Lina Baz Salha Algarni Mona Al-thepyani Abdullah Aldairi Hana Gashlan 《Molecules (Basel, Switzerland)》2022,27(22)
Epidemiological studies have shown that the consumption of a high-fat diet (HFD) is positively related to the development of obesity. Lycopene (LYC) can potentially combat HFD-induced obesity and metabolic disorders in rats. This study aimed to investigate the effect of LYC on metabolic syndrome and assess its anti-inflammatory and antioxidant effects on the liver and adipose tissue in rats fed an HFD. Thirty-six male Wistar albino rats were divided into three groups. Group Ι (the control group) was fed a normal diet, group ΙΙ (HFD) received an HFD for 16 weeks, and group ΙΙΙ (HFD + LYC) received an HFD for 12 weeks and then LYC (25 mg/kg b.wt) was administered for four weeks. Lipid peroxidation, antioxidants, lipid profile, liver function biomarkers, and inflammatory markers were determined. The results showed that long-term consumption of an HFD significantly increased weight gain, liver weight, and cholesterol and triglyceride levels. Rats on an HFD displayed higher levels of lipid peroxidation and inflammatory markers. Moreover, liver and white adipose tissue histopathological investigations showed that LYC treatment mended the damaged tissue. Overall, LYC supplementation successfully reversed HFD-induced changes and shifts through its antioxidant and anti-inflammatory activity. Therefore, LYC displayed a therapeutic potential to manage obesity and its associated pathologies. 相似文献
52.
Ryeojin Ko Jeongin Seo Hana Park Nawon Lee Soo Young Lee 《Experimental & molecular medicine》2022,54(11):2092
The Pim (proviral integration site for Moloney murine leukemia virus) proteins compose a serine threonine kinase family whose members regulate cell proliferation, migration and cell survival. However, whether Pim kinases participate in innate immune responses is unclear. Here, we show for the first time that Pim1 plays an essential role in the production of interferon (IFN)-β by macrophages after their Toll-like receptor (TLR) pathway is activated by pathogen-associated molecular patterns (PAMPs). Specifically, Pim1 was quickly upregulated in an NF-κB-dependent manner after TLR stimulation with PAMPs. Pim1 deficiency reduced TLR3- or TLR4-stimulated IFN-β and IFN-stimulated gene (ISG) expression but not proinflammatory cytokine expression in macrophages. Mechanistically, Pim1 specifically upregulates IRF3 phosphorylation and nuclear translocation. However, this role is not dependent on Pim1 kinase activity. Rather, Pim1 appears to promote IRF3 phosphorylation by enhancing the formation of IFN-β signaling complexes composed of TRIF, TRAF3, TBK1, and IRF3. Poly (I:C)-treated Pim1−/− mice produced less serum IFN-β and were less likely to survive than wild-type mice. These findings show for the first time that Pim1 participates in TLR-mediated IFN-β production, thus revealing a novel target for controlling antiviral innate immune responses.Subject terms: Toll-like receptors, Phagocytes 相似文献
53.
Lísa M Netušilová K Franěk L Dvořáková H Vrkoslav V Holčapek M 《Journal of chromatography. A》2011,1218(42):7499-7510
Fatty acid (FA) and triacylglycerol (TG) composition of natural oils and fats intake in the diet has a strong influence on the human health and chronic diseases. In this work, non-aqueous reversed-phase (NARP) and silver-ion high-performance liquid chromatography with atmospheric pressure chemical ionization mass spectrometry detection and gas chromatography with flame-ionization detection (GC/FID) and mass spectrometry detection are used for the characterization of FA and TG composition in complex samples of animal fats from fallow deer, red deer, sheep, moufflon, wild boar, cock, duck and rabbit. The FA composition of samples is determined based on the GC/FID analysis of FA methyl esters. In total, 81 FAs of different acyl chain length, double bond (DB) number, branched/linear, cis-/trans- and DB positional isomers are identified. TGs in animal fats contain mainly monounsaturated and saturated FAs. High amounts of branched and trans-FAs are observed in the samples of ruminants. In NARP mode, individual TG species are separated including the separation of trans- and branched TGs. Silver-ion mode provides the separation of TG regioisomers, which enables the determination of their ratios. Great differences in the preference of unsaturated and saturated FAs in the sn-2 position on the glycerol skeleton are observed among individual animal fats. Unsaturated FAs are preferentially occupied in the sn-2 position in all animal samples except for wild boar with the strong preference of saturated FAs in the sn-2 position. 相似文献
54.
Ostatná V Vaisocherová H Homola J Hianik T 《Analytical and bioanalytical chemistry》2008,391(5):1861-1869
We report a multichannel surface plasmon resonance (SPR) sensor for detection of thrombin via DNA aptamers immobilized on
the SPR sensor surface. A detailed investigation of the effect of the immobilisation method on the interaction between thrombin
and DNA aptamers is presented. Three basic approaches to the immobilisation of aptamers on the surface of the SPR sensor are
examined: (i) immobilisation based on chemisorption of aptamers modified with SH groups, (ii) immobilisation of biotin-tagged
aptamers via previously immobilized avidin, neutravidin or streptavidin molecular linkers, and (iii) immobilisation employing
dendrimers as a support layer for subsequent immobilisation of aptamers. A level of nonspecific binding of thrombin to immobilized
human serum albumin (HSA) for each of the immobilisation methods is determined. Immobilisation of aptamers by means of the
streptavidin–biotin system yields the best results both in terms of sensor specificity and sensitivity. 相似文献
55.
Mag. pharm. Dr. Gerhard Buchbauer Günther W. Hana Heinrich Koch 《Monatshefte für Chemie / Chemical Monthly》1976,107(2):387-394
An improved synthesis of the title compound (1) is described. The catalytical action of variousLewis acids on the sterically hinderedDiels-Alder reaction of mesityl oxide with cyclopentadiene has been investigated. The mixture ofendo- andexo-isomers of the unsaturated intermediate2 yielded pure1 on hydrogenation and isomerization by sodium methoxide. The proof of theexo-configuration of the acetyl group has been achieved by mass spectra and 100 MHz1H-NMR spectra.
Herrn Prof. Dr.M. Pailer mit den besten Wünschen zum 65. Geburtstag gewidmet. 相似文献
Herrn Prof. Dr.M. Pailer mit den besten Wünschen zum 65. Geburtstag gewidmet. 相似文献
56.
Electrothermal atomisation of mercury in the presence of thiols. Sample stabilisation during the drying step is important for the determination of mercury by electrothermal a.a.s. Addition of complexing agents with thiol groups makes possible the analysis of pure aqueous solutions. Mercury can be determined at concentrations down to 5 × 10-6% with a reproducibility of 2–10%. Small amounts of acids and salts depress the efficiency of stabilisation, so that separation becomes necessary. The use of a selective ion-exchanger with thiol groups solves the problems of sample storage, separation and stabilisation. The enrichment enhances the sensitivity by two orders of magnitude. Determinations of 2–20 ppb Hg in water, 0.2–2 M HC1 and 0.2–1 M NaCl are reported. 相似文献
57.
The stability of the cytostatics, ftorafur and fluorouracil injections, was studied in dependence on irradiation with UV light and on the medium temperature and pH. In the first stage of the thermal and photochemical decomposition of ftorafur, tetrahydrofuran dissociated from position N1 in the pyrimidine ring and 5-fluorouracil was formed. In the second stage of the thermal and photochemical decomposition of ftorafur, the pyrimidine ring opened between N3 and C4 and between C6 and N1, with formation of urea. Ftorafur, fluorouracil, and urea were determined using thin-layer chromatography and spectrophotometry in the UV and visible region. 相似文献
58.
Varilová T Seménková H Horák P Madera M Pacáková V Tichá M Stulík K 《Journal of separation science》2006,29(8):1110-1115
Interactions of boar, bull, and human seminal plasma proteins with heparin and phosphorylcholine were studied by affinity LC using heparin immobilized to a Toyopearl support. A step gradient elution from 0.15 to 1.50 M NaCl was employed to elute the seminal plasma proteins. Relative amounts of the heparin-binding fraction of seminal plasma proteins (H+) in seminal plasma of three species were determined. Further on, the fraction of seminal plasma proteins interacting with phosphorylcholine-binding proteins (P+) was evaluated. P+ proteins were not found in human seminal plasma and their highest amount was present in bull seminal plasma. A CE method was developed for separation of seminal plasma proteins. Various capillaries and separation conditions were tested; the best resolution was obtained in a bare-silica capillary, with a micellar system consisting of a 0.02 M borate buffer and 0.05 M SDS pH 10.0. The optimized conditions were applied to the identification of the components in boar plasma. 相似文献
59.
Refat MS Sadeek SA Khater HM 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,64(3):778-788
The rapid interaction between o-tolidine and p-toluidine (pi-donors) with the pi-acceptors, e.g., 3,5-dinitrobenzoic acid (DNB) and 2,6-dichloroquinone-4-chloroimide (DCQ) results in the formation of 1:1 charge-transfer complexes as the final products, [(o-tolidine) (acceptor)] and [(p-toluidine) (acceptor)]. The final products of the reactions have been isolated and characterized using FTIR, 1HNMR spectroscopy and elemental analysis as well as photometric titration. The stoichiometry and apparent formation constants of the complexes formed were determined by applying the conventional spectrophotometric molar ratio method. 相似文献
60.
Lenka Morávková Ondřej Vopička Jiří Vejražka Hana Vychodilová Zuzana Sedláková Karel Friess Pavel Izák 《Chemical Papers》2014,68(12):1739-1746
The emissions of hydrocarbons from fossil fuels into atmosphere entail both an economic loss and an environmental pollution. Membrane separations can be used for vapour recovery and/or vapour removal from the permanent gas stream, given that the appropriate membrane is identified. A neat poly(vinylidene fluoride-co-hexafluoropropylene) membrane is impermeable to both the representatives of aliphatic hydrocarbons and branched hydrocarbons, namely hexane and isooctane, whereas the permeation flux is enhanced by the presence of 80 mass % of the ionic liquid 1-ethyl-3-methylimidazolium bis(trifluoromethylsulphonyl)imide in the membrane, as detailed in this work. The permeabilities of hydrocarbon vapours were determined from the binary mixture containing hydrocarbon and nitrogen to simulate the real input of an air stream containing a condensable hydrocarbon. The diffusion coefficient determined from sorption measurements was higher for hexane, as would be expected for a smaller molecule, whereas both the sorption isotherms and permeabilities of the hydrocarbons studied were found to be almost identical. It is possible that the sorption effect predominates in the transport mechanism for VOCs/N2 separations. 相似文献