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41.
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
42.
Twin-field quantum key distribution (TF-QKD) has attracted considerable attention because it can exceed the basic rate-distance limit without quantum repeaters. Its variant protocol, sending or not-sending quantum key distribution (SNS-QKD), not only fixes the security vulnerability of TF-QKD, but also can tolerate large misalignment errors. However, the current SNS-QKD protocol is based on the active decoy-state method, which may lead to side channel information leakage when multiple light intensities are modulated in practice. In this work, we propose a passive decoy-state SNS-QKD protocol to further enhance the security of SNS-QKD. Numerical simulation results show that the protocol not only improves the security in source, but also retains the advantages of tolerating large misalignment errors. Therefore, it may provide further guidance for the practical application of SNS-QKD. 相似文献
43.
Baiji Xue Yanhua Yu Guoqiang Peng Mengmeng Sun Peng Lv Xuefeng Li 《Molecules (Basel, Switzerland)》2022,27(10)
Amphotericin B (AMB) is an antifungal drug used for serious fungal infections. However, AMB has adverse reactions such as nephrotoxicity, which limit the clinical application of AMB alone or in combination with other antifungal drugs. Nano or micro drug delivery systems (DDS) have been proven to be effective in reducing the toxic and side effects of drugs. Further, the combination of AMB with other compounds with antifungal activity, such as curcumin (CM), may enhance the synergistic effects. Herein, AMB and CM were co-loaded into porous poly (lactic-co-glycolic acid) (PLGA) microparticles (MPs) to prepare AMB/CM-PLGA MPs. The AMB/CM-PLGA MPs showed a remarkably reduced hemolysis (62.2 ± 0.6%) compared to AMB (80.9 ± 1.1%). The nephrotoxicity of AMB/CM-PLGA MPs is significantly lower than that of AMB. In vitro, AMB/CM-PLGA MPs had better inhibitory effects on the adhesion and biofilm formation of Candida albicans compared with AMB. Experiments on mice infected with C. albicans showed that AMB/CM-PLGA MPs have a better therapeutic effect than AMB in vivo. In summary, AMB/CM-PLGA MPs may be a novel and promising therapeutic candidate for fungal infection. 相似文献
44.
A high-performance liquid chromatography-tandem mass spectrometry method was established for the simultaneous determination of mycophenolic acid, mycophenolate mofetil, tacrolimus, rapamycin, everolimus and pimecrolimus in human whole blood by optimizing the QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) preparation method. Whole blood was extracted into ethyl acetate, salted out with anhydrous magnesium sulfate, and purified with ethylenediamine-N-propyl silane adsorbent. The supernatant was evaporated under nitrogen until dry and finally reconstituted in methanol. Chromatographic separation was performed on an Agilent Poroshell 120 EC-C18 column in methanol (mobile phase A)-water (optimized for 0.1% acetic acid and 10 mM ammonium acetate, mobile phase B) at a 0.3 mL·min−1 flow rate. Electrospray ionization and positive ion multiple reaction monitoring were used for detection. The time for of analysis was 13 min. The calibration curves range of tacrolimus, rapamycin, everolimus and pimecrolimus were in the range of 1–100 ng·mL−1, mycophenolate mofetil in the range of 0.1–10 ng·mL−1 and mycophenolic acid at 10–1000 ng·mL−1. All correlation coefficients were >0.993. The coefficients of variation (CV, %) for inter-day and intra-day precision were less than 10%, while the spiked recoveries were in the range of 92.1% to 116%. Our method was rapid, sensitive, specific, and reproducible for the simultaneous determination of six immunosuppressants in human whole blood. Importantly, our approach can be used to monitor drug concentrations in the blood to facilitate disease treatment. 相似文献
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46.
Chang-Sheng Zhang Ya-Ping Shao Fu-Min Zhang Xue Han Xiao-Ming Zhang Kun Zhang Yong-Qiang Tu 《Chemical science》2022,13(28):8429
A novel classical kinetic resolution of 2-aryl-substituted or 2,3-disubstituted cyclobutanones of Baeyer–Villiger oxidation catalyzed by a Cu(ii)/SPDO complex is reported for the first time, producing normal lactones in excellent enantioselectivities (up to 96% ee) and regioselectivities (up to >20/1), along with unreacted ketones in excellent enantioselectivities (up to 99% ee). The current transformation features a wide substrate scope. Moreover, catalytic asymmetric total syntheses of natural eupomatilones 5 and 6 are achieved in nine steps from commercially available 3-methylcyclobutan-1-one.A novel classical kinetic resolution of Baeyer–Villiger oxidation catalyzed by a Cu(ii)/SPDO complex with excellent enantioselectivity, regioselectivity and wide substrate scope is reported for the first time and explore the synthetic application. 相似文献
47.
本文在伏安法测电阻实验的基础上,将系统误差修正方法进行逆运用,介绍一种测量电表内阻的方法。 相似文献
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