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排序方式: 共有1547条查询结果,搜索用时 15 毫秒
931.
Federica DAria Bruno Pagano Luigi Petraccone Concetta Giancola 《International journal of molecular sciences》2021,22(1)
DNA G-quadruplexes (G4s) form in relevant genomic regions and intervene in several biological processes, including the modulation of oncogenes expression, and are potential anticancer drug targets. The human KRAS proto-oncogene promoter region contains guanine-rich sequences able to fold into G4 structures. Here, by using circular dichroism and differential scanning calorimetry as complementary physicochemical methodologies, we compared the thermodynamic stability of the G4s formed by a shorter and a longer version of the KRAS promoter sequence, namely 5′-AGGGCGGTGTGGGAATAGGGAA-3′ (KRAS 22RT) and 5′-AGGGCGGTGTGGGAAGAGGGAAGAGGGGGAGG-3′ (KRAS 32R). Our results show that the unfolding mechanism of KRAS 32R is more complex than that of KRAS 22RT. The different thermodynamic stability is discussed based on the recently determined NMR structures. The binding properties of TMPyP4 and BRACO-19, two well-known G4-targeting anticancer compounds, to the KRAS G4s were also investigated. The present physicochemical study aims to help in choosing the best G4 target for potential anticancer drugs. 相似文献
932.
Applied Intelligence - Berth allocation is one of the crucial points for efficient management of ports. This problem is complex due to all possible combinations for assigning ships to available... 相似文献
933.
Luigi Brunetti Lujing Wang Andrew Wassef Yongjia Gong Anita Brinker Brian Buckley Peter E. Lipsky Patricia Ondar George Poiani Liping Zhao Ah-Ng Kong Naomi Schlesinger 《Molecular nutrition & food research》2023,67(9):2200550
Scope
Tart cherries (TCs) contain high levels of anthocyanins that exert potent antioxidant and antiinflammatory effects and potentially benefit individuals with gout.Methods and results
This study aims to quantitate the major anthocyanins in TC Juice Concentrate (TCJC) and identify the pharmacokinetic (PK) and pharmacodynamic (PD) parameters of the major anthocyanin cyanidin-3-glucosylrutinoside (C3GR). A PK-PD study enrolling human subjects with a history of gout is performed. Subjects are randomized to receive either 60 or 120 mL of TCJC. Anthocyanins are quantitated using liquid chromatography-mass spectroscopy (LCMS). Antioxidant and antiinflammatory mRNA expression is measured using real-time qPCR before and after the administration of TCJC. A population PK model (popPK) is fit to the experimental data, and an indirect PD model (IDR) is constructed in Monolix.Conclusion
Of the bioavailable anthocyanins, C3GR achieves the highest plasma concentration in a dose-dependent manner. A popPK predicts anthocyanin exposure, and an IDR produces reasonable approximations of PD effects. 相似文献934.
An improvement of the trajectory matching algorithm is presented, which is based on the use of the derivative of trajectories and of the projection of experimental sinogram lines in the factor space determined by sinogram lines of projections of a model. The algorithm performance is illustrated by use of different phantom structures, to show the effect of symmetry on trajectory matching. A GroEL complex has also been reconstructed from both cryo-negatively stained and unstained frozen-hydrated samples. The refinement of this structure has been carried out by the trajectory matching algorithm as well as by conventional cross-correlation methods. Slight differences among the two results are discussed. The improved trajectory matching algorithm, based on chi2 distances, runs much faster than correlation analysis and looks satisfactory as for the quality of the reconstructed structures. 相似文献
935.
936.
A new method for recovering and purifying sesquiterpene lactones (SLs) and optimise the solvent system for their extraction from freeze-dried chicory leaves was studied. Catalogna (leafy chicory) and Head Radicchio types were used as test samples. Solid phase extraction (SPE) employing silica-based cartridges allowed a fast and straightforward purification of SL from interfering phenolics, before HPLC determination. Under these conditions, SL were eluted during loading and washing steps whereas polar phenolic compounds were retained on silica stationary phase. Hydrophilic mixtures methanol/water acidified by small percentages of formic acid led to consistently higher SL recoveries in comparison to organic solvents and enabled the simultaneous extraction of phenolics. Phenolic recovery in crude extracts was assessed at levels higher than 95% for both Catalogna and Head Radicchio. Total, free and bound SL amounts detected in extract obtained by 2% (v/v) formic acid in methanol/water 4/1 (v/v) were 2223.4, 778.5 and 1444.9 mg/kg of dried product in Catalogna, and 401.2, 105.1 and 296.0 in Head Radicchio. In both cases, recoveries were consistently higher than those obtained with methanol alone. 相似文献
937.
938.
Joanna Natalia Buffoni Ivan Bonizzi Alfredo Pauciullo Luigi Ramunno Maria Feligini 《Food chemistry》2011
In this work, the whey protein fractions from 120 Mediterranean water buffalo individual milks were analysed by microchip electrophoresis (MCE), reverse-phase high-performance liquid chromatography (RP-HPLC) and mass spectrometry (ESI-MS). Validation procedures were carried out for both MCE and HPLC. The chromatographic analysis allowed the complete separation of the whey protein fractions, resulting in a well-defined peak structure; the adopted RP-HPLC and ESI-MS protocols provided identification of β-lactoglobulin (18,266 Da), α-lactoalbumin (14,236 Da) and serum albumin (66,397 Da). The calculated mean concentrations were 4.04 g/l, 2.45 g/l and 0.35 g/l, respectively. 相似文献
939.
Volatile compounds and compositional quality of virgin olive oil from Oueslati variety: Influence of geographical origin 总被引:2,自引:0,他引:2
Ouni Youssef Flamini Guido Issaoui Manel Nabil Ben Youssef Cioni Pier Luigi Hammami Mohamed Douja Daoud Zarrouk Mokhtar 《Food chemistry》2011
Headspace solid-phase microextraction (HS-SPME) was applied to the analysis of volatile compounds of virgin olive oils from Oueslati variety cultivated in different geographical areas. Thus, olives at the same stage of maturation were harvested from seven regions in the Centre and the South of the country for oil extraction and analysis. Twenty-seven compounds were characterised by GC-FID and GC–MS. Compounds belonging mainly to alcohols, esters, aldehydes, ketones and hydrocarbons chemical classes characterised the volatile profiles. Significant differences in the proportion of volatiles from oils of different geographical origins were detected. The results suggest that, besides genetic factors, environmental conditions influence volatile formation. 相似文献
940.