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Ting Liu Prof. Xin Huang Lingyun Zhao Zhongqing Xiao Zengbei Li Yi Xin Shanshan Yang Di Guo Wenfei Zhao Dr. Yang Mi Prof. Hongyun Li 《ChemistryOpen》2021,10(9):882-888
Lung cancer is the leading cause of cancer deaths worldwide and most cancer patients receiving conventional chemotherapy suffer from severe side effects due to the non-selective effects of chemotherapeutic drugs on normal cells. Targeted nanomaterials can obtain excellent accumulation at the tumor site through their active or passive targeting mechanisms, thereby reducing the toxicity of the drugs in various ways. In this study, hyaluronic acid (HA) which could specifically bind to CD44 on the surface of tumor cells, was used to modify amine-caged platinum nanoclusters (Pt NCs-NH2) to obtain targeting HA-Pt NCs-NH2. Based on the differential expression of CD44 on the surface of three lung cells (non-small cell lung cancer cell H1299, small cell lung cancer cell H446, and embryonic lung fibroblast HFL1), HA-Pt NCs-NH2 can differentially enter the three cells and achieve their targeting of non-small cell lung cancer cell (NSCLC) cells. Pt NCs significantly inhibited the proliferation, migration and invasion of NSCLC cells and induced their apoptosis in comparison of classical cisplatin and carboplatin, showing a bright future in early diagnosis and treatment of NSCLC. 相似文献
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Xin Zheng Weicong Wang Yanbao Zhang Yuxiang Ma Hongyun Zhao Huitao Gao Pei Hu Ji Jiang 《Biomedical chromatography : BMC》2020,34(2):e4704
Abivertinib represents a highly selective irreversible epidermal growth factor receptor tyrosine kinase inhibitor. Two major metabolites of abivertinib, M7 and MII-6, were detected in human plasma, which are recommended to be monitored for safety reasons in clinical trial. A high-throughput quantification method utilizing liquid chromatography–tandem mass spectrometry was designed and verified to quantify abivertinib's primary metabolites in human plasma. Solid-phase extraction was used to process the plasma, and then the analytes underwent a gradient elution separation in an Aquity UPLC BEH C18 column (1.7 μm, 2.1 × 50 mm) with mobile phase A (10 mm ammonium acetate containing 0.1% formic acid) and mobile phase B (methanol–acetonitrile, 2:8, v/v, with 0.1% formic acid). Ion transitions of M7 (m/z 490.2 → 405.1) and MII-6 (m/z 476.2 → 391.1) were monitored under multiple reaction monitoring mode and electrospray ionization in positive ion mode. This simultaneous determination method was found to have acceptable precision, accuracy and linearity in the 0.5–500 ng/mL range for M7 and the 0.5–500 ng/mL range for MII-6, accompanied by a mild matrix effect but high recovery. Further stability assessments indicated that both analytes remained stable throughout the entire experimental process from harvesting whole blood to plasma extraction and analysis. 相似文献
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Li Feng Chen Liying Zhang Hongyun Wu Qingan Li Yanhong Cui Zhanhua Niu Yunyin Jiang Haigang 《Transition Metal Chemistry》1995,20(5):511-513
Summary Formylferrocenyl-3-hydroxyl-2-naphthoylhydrazone and its transition metal coordination compounds have been synthesized and characterized by elemental analyses, i.r., 1H-n.m.r., u.v.-vis., t.g.-d.t.a. and molar conductivities. The results show that the ligand coordinates to transition metal ions in the enolic form, accompanied by the release of acetate or nitrate. 相似文献
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设E是阿基米德Riesz空间,有弱单位元e和极大不相交系{ei:i∈I},其中每一个ei都是投影元素.由ei生成的主带记为B(ei).本文考虑如下论述:(a)存在完全正则Hausdorf空间X,使E是Riesz同构于C(X);(b)对每一个i∈I,存在一个完全正则Hausdorf空间Xi使B(ei)是Riesz同构于C(Xi).我们证明(a)可推出(b).但其逆在一般情况下不成立.当(b)成立时,我们得到一些与(a)等价的论述. 相似文献
47.
聚马来松香乙二醇酯Cu(Ⅱ)配合物固定化漆树漆酶的研究 总被引:1,自引:0,他引:1
制备了聚马来松香乙二醇酯(MEEP)Cu2 、Ni2 、Ca2 和Mg2 金属离子配合物,并分别以4种配合物为载体固定化漆树漆酶,初步探讨了反应时间对酶固定化的影响,考察了固定化酶的性质.实验结果表明,在反应温度为25℃条件下,漆树漆酶的最佳固定化时间为16h;MEEPCu2 配合物固定化酶的固定化结果较好,重复使用6次后,酶相对保留活力为55.0%;该固定化酶的最适作用温度为40℃,pH值范围为5.89~9.23,固定化漆树漆酶具有比游离酶更好的热稳定性和更广泛的pH值适用范围. 相似文献
48.
Pseurotin A was isolated from a culture of marine Bacillus sp. FS8D and showed to be active against the proliferation of four different glioma cells with IC50 values of 0.51–29.3 μM. It has been found that pseurotin A downregulated the expression of tumour glycolytic enzymes pyruvate kinase M2 (PKM2) and lactate dehydrogenase 5 (LDH5) and upregulated the expression of pyruvate dehydrogenase beta (PDHB), adenosine triphosphate synthase beta (ATPB) and cytochrome C (Cyto-C), the important regulators for tricarboxylic acid cycle and oxidative phosphorylation. The data suggested that targeting multiple metabolic enzymes might be one of the antiglioma mechanisms of pseurotin A. 相似文献
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Hongyun Liu 《Analytica chimica acta》2003,481(1):91-99
Direct electrochemistry and electrocatalysis of heme proteins, such as hemoglobin (Hb), myoglobin (Mb), and horseradish peroxidase (HRP), incorporated in gluten biopolymer films cast on pyrolytic graphite (PG) electrodes, were studied by voltammetry and amperometry. All the three protein-gluten films exhibited a pair of well-defined, quasi-reversible cyclic voltammetric peaks at about −0.28 V versus saturated calomel electrode (SCE) in pH 5.5 buffers, respectively, characteristic of the heme Fe(III)/Fe(II) redox couples, indicating enhanced electron transfer between the proteins and PG electrodes in a gluten film environment. The protein-gluten hydrogel films showed excellent stability. Positions of Soret absorption band of protein-gluten films suggested that the heme proteins kept their secondary structure similar to their native state in the films in the medium pH range. The heme proteins in gluten films were act as a biologic catalyst to catalyze reduction of oxygen or hydrogen peroxide. The voltammetric or amperometric responses of H2O2 at the protein-gluten film electrodes could be used to determine the concentration of H2O2 in solution. 相似文献