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Abstract Due to the interest in the potential pharmacological application of dandelion, the chemical constituents and activities of Taraxacum mongolicum Hand.-Mazz were studied. Box–Behnken response surface methodology was employed to optimize the protocol for extraction of flavonoid from dandelion. The molecular structures of different flavonoid compounds were acquired and analyzed by liquid chromatography-mass spectrometry (LC–MS) and nuclear magnetic resonance (NMR) spectroscopy. Several major flavonoid compounds were isolated and purified, namely, hesperetin-5′-O-β-rhamnoglucoside, hesperetin-7-glucuronide, kaempferol-3-glucoside, baicalein, hyperseroside, which were extracted for the first time from dandelion. Hesperetin-5′-O-β-rhamnoglucoside was identified as a new type of flavonoid that had never reported in the literature. This new flavonoid has outstanding antioxidant activity, as shown by its IC50 value (8.72 mg/L) for scavenging DPPH free radicals. The determination of the structure-related antioxidant activities could be interpreted based on DFT calculations. As such, we have not only illustrated the rich flavonoid contents in Taraxacum mongolicum Hand.-Mazz, but also revealed new types of flavonoid compounds in dandelion in terms of structure and antioxidant properties.

Abstract Lysine 2-hydroxyisobutyrylation (Khib) is a novel naturally occurring post-translational modification. The system Khib identification at proteomics level has been performed in various species and tissues to characterize the role of Khib in biological activities. However, the study of Khib in plant species is relatively less. In the present study, the first plant root tissues lysine 2-hydroxyisobutyrylome analysis was performed in wheat with antibody immunoprecipitation affinity, high resolution mass spectrometry-based proteomics and bioinformatics analysis. In total, 6328 Khib sites in 2186 proteins were repeatedly identified in three replicates. These Khib proteins showed a wide subcellular location distribution. Function and pathways characterization of these Khib proteins indicated that many cellular functions and metabolism pathways were potentially affected by this modification. Protein and amino acid metabolism related process may be regulated by Khib, especially ribosome activities and proteins biosynthesis process. Carbohydrate metabolism and energy production related processes including glycolysis/gluconeogenesis, TCA cycle and oxidative phosphorylation pathways were also affected by Khib modification. Besides, root sulfur assimilation and transformation related enzymes exhibited Khib modification. Our work illustrated the potential regulation role of Khib in wheat root physiology and biology, which could be used as a useful reference for Khib study in plant root.

Abstract To investigate the usefulness of intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) in discriminating the pathological complete response (pCR) to neoadjuvant chemoradiotherapy (nCRT) in locally advanced rectal cancer (LARC), 42 patients underwent preoperative IVIM-DWI before (pre-nCRT) and after nCRT (post-nCRT). The values of pre-nCRT and post-nCRT IVIM-DWI parameters (ADC, D, D* and f), together with the percentage changes (∆% parametric value) induced by nCRT, were compared between the pCR (tumour regression grade [TRG] 4) and non-pCR (TRG 0, 1, 2 or 3) groups and between the GR (TRG 3 or 4) and PR (TRG 0, 1 or 2) groups based on the Dworak TRG system. After nCRT, the ADC and D values for LARC increased significantly (all P

This study presents one of the first long term datasets including a statistical summary of PM2.5 concentrations obtained from one-year monitoring in 190 cities in China. We found only 25 out of 190 cities could meet the National Ambient Air Quality Standards of China, and the population-weighted mean of PM2.5 in Chinese cities are 61 μg/m(3), ~3 times as high as global population-weighted mean, highlighting a high health risk. PM2.5 concentrations are generally higher in north than in south regions due to relative large PM emissions and unfavorable meteorological conditions for pollution dispersion. A remarkable seasonal variability of PM2.5 is observed with the highest during the winter and the lowest during the summer. Due to the enhanced contributions from dust particles and open biomass burning, high PM2.5 abundances are also found in the spring (in Northwest and West Central China) and autumn (in East China), respectively. In addition, we found the lowest and highest PM2.5 often occurs in the afternoon and evening hours, respectively, associated with daily variation of the boundary layer depth and anthropogenic emissions. The diurnal distribution of the PM2.5-to-CO ratio consistently displays a pronounced peak during the afternoon periods, reflecting a significant contribution of secondary PM formation.