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Anti-Breast Cancer Active Components in Loquat Leaves and Their Inhibitory Effects on Topoisomerase Ⅰ
LIU Jiayao;YANG Junlong;XIE Yuman;HUANG Hui;ZENG Huang;NIE Hua;GUO Bohong;In order to explore the anti-breast cancer active components in loquat leaves and their inhibitory effects on topoisomerase Ⅰ(TOP Ⅰ),we integrated network pharmacology to screen the anti-breast cancer active components from loquat leaves and core pathways.Moreover,we analyzed the interaction mode and inhibitory efficacy of the active components with TOP Ⅰ by using molecular docking and TOP Ⅰ-mediated DNA relaxation experiments.Furthermore,we investigated the effects of the active components on the proliferation,migration,cloning,and apoptosis of human breast cancer cells MCF-7 by cytotoxicity experiments,cell scratch healing experiments,cell cloning experiments,and cell apoptosis experiments.The results show that quercetin,ellagic acid,(-)-epigallocatechin gallate,and kaempferol are the key anti-breast cancer active components in loquat leaves,they can stably bind to the catalytic domain of TOP Ⅰ.All four active components can inhibit the activity of TOP Ⅰ in a concentration-dependent manner.The half-maximal inhibitory concentrations(IC50) of the four active components are 160.70,84.82,72.54,and 80.67 μmol·L-1,respectively,significantly inhibiting the growth,proliferation,migration,and cloning of MCF-7 cells and promoting cell apoptosis.This study provides a theoretical basis for the research of antitumor activity of loquat leaves extracts.
Research Progress in Carbon-Based Catalysts Modification Strategies and Electrochemical Reactor for Synthesis of H_2O2 via 2e-ORR
LU Zilan;JIA Daqing;HU Huawei;ZHU Leilei;KHAN Asim;XU Wenxuan;LIAO Benren;ZHANG Lehua;The synthesis of hydrogen peroxide(H_2O2) via two-electron oxygen reduction reaction(2e-ORR) has become a new and sustainable alternative to industrial anthraquinone process due to its advantages of normal temperature and pressure operation,green raw materials,and renewable energy.Based on the brief explanation of synthetic mechanism of H_2O2 via 2e-ORR,we review the modification strategies of carbon-based catalysts,including heteroatom doping,defect engineering,functional groups,etc.At the same time,we summarize the structure characteristics and application scenarios of H-type,flow-type,and membrane electrode assembly(MEA) reactors,and point out the challenges faced by the current technology,which provides a theoretical support for the research of H_2O2 synthesis via 2e-ORR.
Preparation and in vitro Dissolution of Imatinib Liposomes
LIU Chunyu;HU Xuelei;In response to the problems of poor solubility,low oral bioavailability,and adverse reactions caused by Imatinib,we prepared Imatinib liposomes by passive drug-loading and active drug-loading processes,respectively.Moreover,we optimized the process parameters through single-factor experiments by using the encapsulation efficiency as an indicator.Furthermore,we systematically studied the microscopic morphology,particle size,Zeta potential,in vitro release behavior,and stability of Imatinib liposomes.The results show that,in the passive drug-loading process, the encapsulation efficiency of Imatinib liposomes prepared by film dispersion method is the highest[(67.0±2.4)%];in the active drug-loading process,under the conditions of the drugloading time of 40 min,the drug-loading temperature of 50 ℃,the drug-lipid ratio of 1:30,the transmembrane pH gradient of 5,and the ammonium sulfate concentration of 100 mmol·L-1,the encapsulation efficiency of Imatinib liposomes is the highest[(65.0±4.1) %].The liposomes prepared by both two processes have regular morphology,spherical or nearly spherical shapes,with a particle size of 100-110 nm,showing good dispersion.The Imatinib liposomes prepared by the active drug-loading process exhibit good sustained-release effect in vitro and have better stability at 4 ℃ refrigeration than that at room temperature.The study lays a foundation for the development of a new drug delivery system for Imatinib.