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871.
Real‐Time Monitoring of Cancer Cell Metabolism and Effects of an Anticancer Agent using 2D In‐Cell NMR Spectroscopy
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Dr. He Wen Yong Jin An Wen Jun Xu Prof. Keon Wook Kang Prof. Sunghyouk Park 《Angewandte Chemie (International ed. in English)》2015,54(18):5374-5377
Altered metabolism is a critical part of cancer cell properties, but real‐time monitoring of metabolomic profiles has been hampered by the lack of a facile method. Here, we propose real‐time metabolomic monitoring of live cancer cells using 13C6‐glucose and heteronuclear two‐dimensional (2D) NMR. The method allowed for metabolomic differentiation between cancer and normal cells on the basis of time‐dependent changes in metabolite concentrations. Cancer cells were found to have large in‐ and out‐flux of pyruvate as well as increased net production of alanine and acetate. The method also enabled evaluation of the metabolic effects of galloflavin whose anticancer effects have been attributed to its specific inhibition of lactate dehydrogenase. Our approach revealed previously unknown functional targets of galloflavin, which were further confirmed at the protein levels. Our method is readily applicable to the study of metabolic alterations in other cellular disease model systems. 相似文献
872.
Jun‐Seok Lee Jae Wook Lee Namyoung Kang Hyung‐Ho Ha Young‐Tae Chang 《Chemical record (New York, N.Y.)》2015,15(2):495-510
Synthetic molecules that modulate and probe biological events are critical tools in chemical biology. Utilizing combinatorial and diversity‐oriented synthetic strategies, access to large numbers of small molecules is becoming more and more feasible, and research groups in this field can take advantage of the power of chemical diversity. Since the majority of early studies were focused on the discovery of compounds that perturb protein functions, diversity‐based approaches are often considered as therapeutic lead discovery tactics. However, the diversity‐oriented approach can also be applied to advance distinct aims, such as target protein identification, or the development of imaging probes and sensors. This review provides a personal perspective of the chemical‐diversity‐based approach and how this principle can be adapted to various chemical biology studies. 相似文献
873.
Targeted Delivery of Vaccine to Dendritic Cells by Chitosan Nanoparticles Conjugated with a Targeting Peptide Ligand Selected by Phage Display Technique
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874.
Hoyeon Lee Soojin Uhm Jung‐Won Shin Hyun Mi Jeon Sun Dongbang Hyo Sung Jung Yun‐Cheol Na Prof. Chulhun Kang Prof. Jong Seung Kim 《化学:亚洲杂志》2015,10(12):2695-2700
A galactose‐appended drug delivery system released camptothecin (CPT) to lysosomes of HepG2 hepatoma cells, resulting in the cell resistance to the anticancer drug. We found that the resistance to CPT is caused by alteration of the drug release from the prodrug in lysosomes, emphasizing that the final delivery locations may critically influence drug efficacy. 相似文献
875.
Xinchen Kang Wenting Shang Qinggong Zhu Jianling Zhang Tao Jiang Buxing Han Zhonghua Wu Zhihong Li Xueqing Xing 《Chemical science》2015,6(3):1668-1675
We proposed a strategy to synthesize mesoporous inorganic salt particles using the special properties of ionic liquid (IL) mixtures, and hollow mesoporous LaF3, NdF3, and YF3 particles were synthesized and characterized using different techniques. The size of the mesopores in the salt particles was about 4 nm, and the materials were full of crystal defects. The LaF3, NdF3 and YF3 particles were used as the catalysts for the cyanosilylation reaction of benzaldehyde using trimethylsilyl cyanide, and Ru/LaF3 and Ru/NdF3, in which Ru nanocatalysts were supported on the LaF3 and NdF3 particles with mesopores, were used to catalyze hydrogenations of benzene to cyclohexane and levulinic acid (LA) to γ-valerolactone (GVL). It was discovered that the activities of these catalysts were unprecedentedly high for these reactions. Detailed study showed that both the crystal defects and the mesopores in the salt particles played crucial roles for the extremely high catalytic activity. 相似文献
876.
Young‐Inn Kim Young‐Kwang Song Daeyoung Kim Sung Kwon Kang 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(10):908-911
Metal complexes with Schiff base ligands have been suggested as potential phosphors in electroluminescent devices. In the title complex, tetrakis[6‐methyl‐2‐({[(pyridin‐2‐yl)methyl]imino}methyl)phenolato‐1:2κ8N,N′,O:O;3:2κ8N,N′,O:O]trizinc(II) hexafluoridophosphate methanol monosolvate, [Zn3(C14H13N2O)4](PF6)2·CH3OH, the ZnII cations adopt both six‐ and four‐coordinate geometries involving the N and O atoms of tetradentate 6‐methyl‐2‐({[(pyridin‐2‐yl)methyl]imino}methyl)phenolate ligands. Two terminal ZnII cations adopt distorted octahedral geometries and the central ZnII cation adopts a distorted tetrahedral geometry. The O atoms of the phenolate ligands bridge three ZnII cations, forming a dicationic trinuclear metal cluster. The title complex exhibits a strong emission at 469 nm with a quantum yield of 15.5%. 相似文献
877.
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879.
Four Metal Complexes Based on Bulky Imidazole Ligands: Solvothermal Syntheses,Crystal Structures,and Fluorescence Properties
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Xue Zhang Sai Li Yue‐Jiao He Tong Han Xiao‐Ling Wang Bang Chen Kang‐Yu Zou Zuo‐Xi Li 《无机化学与普通化学杂志》2015,641(11):1874-1880
In order to explore the influences of (de‐)protonation of the imidazole ring on the structural diversity of the resulting complexes, the imidazole‐based ligands 4, 5‐diphenylimidazole (Hdpi) and 1H‐phenanthro[9, 10‐d]imidazole (Hpi) were utilized as bulky building blocks to construct four complexes by solvothermal reactions, i.e. [Ag(Hdpi)2](NO3) · (H2O) ( 1 ), [Cu(dpi)]∞ ( 2 ), [Cu(Hpi)(NO3)]∞ ( 3 ), and [(H2pi)(NO3)] · H2O ( 4 ). In complex 1 , two Hdpi ligands adopt a monodentate pattern and coordinate with one AgI ion to form a mononuclear unit, which is further connected by hydrogen bonds into a 1D supramolecular helix. The deprotonated dpi ligand of 2 acts in bidentate mode, and bridges CuI ions to afford a 1D chain. In 3 , the NO3– ion, acts as a monodentate bridging ligand and joins CuI ions to generate a 1D chain. The Hpi ligand employs a monodentate mode to bond with CuI ions of the 1D chain. 4 is protonated and two H2pi nitrogen atoms are free of coordination. Interestingly, hydrogen bonds among the NO3– ion, the H2pi ligand, and the water molecule yield a macro ring R44(14). The resulting structural diversity reveals that the (de‐)protonation of imidazole ring directly steers the coordination number of ligand, and thus causes a significant effect on the structure, especially the dimensionality. Furthermore, the solid‐state fluorescence properties of the free ligands and compounds 1 – 4 were studied at room temperature. 相似文献
880.