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941.
Miaomiao Chi Kunming Qin Lei Cao Min Zhang Yingying Su Xun Gao 《Molecules (Basel, Switzerland)》2022,27(10)
Coronary heart disease (CHD), which has developed into one of the major diseases, was reported to be treated by the target of peroxisome proliferators-activate receptor γ (PPAR-γ). As a natural medicine long used in the treatment of CHD, there are few studies on how to screen the target active compounds with high specific activity from Choerospondias axillaris. To advance the pace of research on target-specific active compounds in natural medicines, we have combined magnetic ligand fishing and functionalized nano-microspheres to investigate the active ingredients of PPAR-γ targets in Choerospondias axillaris. The PPAR-γ functionalized magnetic nano-microspheres have been successfully synthesized and characterized by vibrating sample magnetometer (VSM), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The specificity, reusability, and reproducibility of the nano-microspheres were investigated with the help of the specific binding of rosiglitazone to PPAR-γ. In addition, the incubation temperature and the pH of the buffer solution in the magnetic ligand fishing were optimized to improve the specific adsorption efficiency of the analytes. Finally, with the aid of ultraperformance liquid chromatography plus Q-Exactive Orbitrap tandem mass spectrometry (UHPLC-Q-Exactive Orbitrap-MS/MS), the 16 active ligands including 9 organic acids, 5 flavonoids, and 2 phenols were found in the ethanolic extracts of Choerospondias axillaris. Therefore, the study can provide a successful precedent for realizing the designated extraction and rapid isolation of target-specific active ingredient groups in the complex mixtures. 相似文献
942.
Bowei Yan Xiaona Ye Jing Wang Junshan Han Lianlian Wu Song He Kunhong Liu Xiaochen Bo 《Molecules (Basel, Switzerland)》2022,27(10)
In the process of drug discovery, drug-induced liver injury (DILI) is still an active research field and is one of the most common and important issues in toxicity evaluation research. It directly leads to the high wear attrition of the drug. At present, there are a variety of computer algorithms based on molecular representations to predict DILI. It is found that a single molecular representation method is insufficient to complete the task of toxicity prediction, and multiple molecular fingerprint fusion methods have been used as model input. In order to solve the problem of high dimensional and unbalanced DILI prediction data, this paper integrates existing datasets and designs a new algorithm framework, Rotation-Ensemble-GA (R-E-GA). The main idea is to find a feature subset with better predictive performance after rotating the fusion vector of high-dimensional molecular representation in the feature space. Then, an Adaboost-type ensemble learning method is integrated into R-E-GA to improve the prediction accuracy. The experimental results show that the performance of R-E-GA is better than other state-of-art algorithms including ensemble learning-based and graph neural network-based methods. Through five-fold cross-validation, the R-E-GA obtains an ACC of 0.77, an F1 score of 0.769, and an AUC of 0.842. 相似文献
943.
Energy storage is an important adjustment method to improve the economy and reliability of a power system. Due to the complexity of the coupling relationship of elements such as the power source, load, and energy storage in the microgrid, there are problems of insufficient performance in terms of economic operation and efficient dispatching. In view of this, this paper proposes an energy storage configuration optimization model based on reinforcement learning and battery state of health assessment. Firstly, a quantitative assessment of battery health life loss based on deep learning was performed. Secondly, on the basis of considering comprehensive energy complementarity, a two-layer optimal configuration model was designed to optimize the capacity configuration and dispatch operation. Finally, the feasibility of the proposed method in microgrid energy storage planning and operation was verified by experimentation. By integrating reinforcement learning and traditional optimization methods, the proposed method did not rely on the accurate prediction of the power supply and load and can make decisions based only on the real-time information of the microgrid. In this paper, the advantages and disadvantages of the proposed method and existing methods were analyzed, and the results show that the proposed method can effectively improve the performance of dynamic planning for energy storage in microgrids. 相似文献
944.
The chemistry of biomass-derived furans is particularly sensitive to ring openings. These side reactions occur during furfuryl alcohol polymerization. In this work, the furan ring-opening was controlled by changing polymerization conditions, such as varying the type of acidic initiator or the water content. The degree of open structures (DOS) was determined by quantifying the formed carbonyl species by means of quantitative 19F NMR and potentiometric titration. The progress of polymerization and ring opening were monitored by DSC and FT-IR spectroscopy. The presence of additional water is more determining on ring opening than the nature of the acidic initiator. Qualitative structural assessment by means of 13C NMR and FT-IR shows that, depending on the employed conditions, poly(furfuryl alcohol) samples can be classified in two groups. Indeed, either more ester or more ketone side groups are formed as a result of side ring opening reactions. The absence of additional water during FA polymerization preferentially leads to opened structures in the PFA bearing more ester moieties. 相似文献
945.
Xue Luan Zhongcheng Cong Tassos P. Anastassiades Yin Gao 《Molecules (Basel, Switzerland)》2022,27(10)
Previously synthesized N-butyrylated hyaluronic acid (BHA) provides anti-inflammatory effects in rat models of acute gouty arthritis and hyperuricemia. However, the mechanism of action remains to be elucidated. Herein, the anti-inflammatory and antioxidative activities of BHA and the targeted signaling pathways were explored with LPS-induced RAW264.7 and an adjuvant-induced inflammation in a rat model. Results indicated that BHA inhibited the generation of pro-inflammatory cytokines TNFα, IL-1β and IL-6, reduced ROS production and down-regulated JAK1-STAT1/3 signaling pathways in LPS-induced RAW264.7. In vivo, BHA alleviated paw and joint swelling, decreased inflammatory cell infiltration in paw tissues, suppressed gene expressions of p38 and p65, down-regulated the NF-κB and MAPK signaling pathways and reduced protein levels of TNFα, IL-1β and IL-6 in joint tissues of arthritis rats. This study demonstrated the pivotal role of BHA in anti-inflammation and anti-oxidation, suggesting the potential clinical value of BHA in the prevention of inflammatory arthritis and is worthy for development as a new pharmacological treatment. 相似文献
946.
Bo-Yang Hsu Chen-Te Jen Baskaran Stephen Inbaraj Bing-Huei Chen 《Molecules (Basel, Switzerland)》2022,27(10)
Ginseng (Panax quinquefolius), a popular herbal and nutritional supplement consumed worldwide, has been demonstrated to possess vital biological activities, which can be attributed to the presence of ginsenosides. However, the presence of ginsenosides in ginseng root residue, a by-product obtained during processing of ginseng beverage, remains unexplored. The objectives of this study were to develop a high-performance liquid chromatography-photodiode array detection-mass spectrometry (HPLC-DAD-ESI-MS) and an ultra-high-performance-liquid-chromatography-tandem mass spectrometry (UPLC-HRMS-MS/MS) method for the comparison of ginsenoside analysis in ginseng root residue. Results showed that by employing a Supelco Ascentis Express C18 column (150 × 4.6 mm ID, particle size 2.7 μm) and a gradient mobile phase of deionized water and acetonitrile with a flow rate at 1 mL/min and detection at 205 nm, a total of 10 ginsenosides, including internal standard saikosaponin A, were separated within 18 min and detected by HPLC-DAD-ESI-MS. Whereas with UPLC-HRMS-MS/MS, all the 10 ginsenosides were separated within six minutes by using an Acquity UPLC BEH C18 column (50 × 2.1 mm ID, particle size 1.7 μm, 130 Å) and a gradient mobile phase of ammonium acetate and acetonitrile with column temperature at 50 °C, flow rate at 0.4 mL/min and detection by selected reaction monitoring (SRM) mode. High accuracy and precision was shown, with limit of quantitation (LOQ) ranging from 0.2–1.9 μg/g for HPLC-DAD-ESI-MS and 0.269–6.640 ng/g for UPLC-HRMS-MS/MS. The contents of nine ginsenosides in the ginseng root residue ranged from <LOQ-26.39 mg/g by HPLC-DAD-ESI-MS and <LOQ-21.25 mg/g by UPLC-HRMS-MS/MS, with a total amount of 38.37 and 34.71 mg/g, respectively. 相似文献
947.
948.
Al/AlN多层膜的摩擦磨损性能研究 总被引:3,自引:0,他引:3
采用柱状靶磁控溅射系统制备Al/AlN纳米多层膜,采用纳米压痕仪测量Al/AlN纳米多层膜的纳米硬度,在UMT-2M型摩擦磨损试验机上评价其摩擦磨损性能.结果表明:当AlN层较厚时,薄膜在很短时间内被磨穿;调节Al/AlN层厚比为2.9/1.1时,薄膜的摩擦磨损性能明显提高;当保持Al/AlN层厚比为2.9/1.1、变化多层膜的调制周期时,薄膜的摩擦系数较低,但硬度较低的薄膜由于承载能力不够,不能够保持优良的摩擦磨损性能. 相似文献
949.
950.
Shang Chen Chenyan Ren Yuan Ji Dongke Liu Xinke Zhang Fengshan Wang 《Molecules (Basel, Switzerland)》2022,27(13)
Thymus immunosuppressive pentapeptide (TIPP) is a novel anti-inflammatory peptide with high efficacy and low toxicity. This study aims to establish a selective LC-MS/MS method for analyzing the analyte TIPP in biological samples, laying the foundation for further PK and PD studies of TIPP. Protein precipitation was conducted in acetonitrile supplemented with 2% formic acid and 25 mg/mL dithiothreitol as a stabilizer, which was followed by backwashing the organic phase using dichloromethane. The chromatographic separation of TIPP was achieved on a C18 column with a gradient elution method. During positive electrospray ionization, TIPP was analyzed via multiple-reaction monitoring. The linear relationships between the concentration of TIPP and peak area in murine plasma cell lysates, supernatants, and the final cell rinse PBS were established within the ranges of 20–5000 ng/mL, 1–200 ng/mL, 10–200 μg/mL, and 0.1–20 ng/mL, respectively (r2 > 0.99). Validated according to U.S. FDA guidelines, the proposed method was proved to be acceptable. Such a method had been successfully applied to investigate the pharmacokinetics of TIPP in mice via subcutaneous injection. The plasma half-life in mice was 5.987 ± 1.824 min, suggesting that TIPP is swiftly eliminated in vivo. The amount of TIPP uptake by RBL-2H3 cells was determined using this method, which was also visually verified by confocal. Furthermore, the effective intracellular concentration of TIPP was deduced by comparing the intracellular concentration of TIPP and degrees of inflammation, enlightening further investigation on the intracellular target and mechanism of TIPP. 相似文献