46 results on '"Yong Yang"'
Search Results
2. Characterization, crystal structure and cytotoxic activity of a rare iridoid glycoside from Lonicera saccata
- Author
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Ren-Yong Yang, Zhaoxia Qu, Ya-Nan Wang, Feng Zhao, Li Ma, Qi Zhang, and Gui-Ge Hou
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Iridoid Glycosides ,Magnetic Resonance Spectroscopy ,Iridoid ,Stereochemistry ,medicine.drug_class ,Crystal structure ,Crystallography, X-Ray ,010402 general chemistry ,01 natural sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Materials Chemistry ,medicine ,Humans ,Moiety ,Physical and Theoretical Chemistry ,chemistry.chemical_classification ,Molecular Structure ,Cytotoxins ,010405 organic chemistry ,Hydrogen bond ,Glycoside ,Hydrogen Bonding ,Condensed Matter Physics ,0104 chemical sciences ,Lonicera ,chemistry ,Pyran ,Two-dimensional nuclear magnetic resonance spectroscopy - Abstract
A new iridoid glycoside, methyl (3R,4R,4aS,7S,7aR)-3-hydroxy-7-methyl-5-oxooctahydrocyclopenta[c]pyran-4-carboxylate-3-O-β-D-(1′S,2′R,3′S,4′S,5′R)-glucopyranoside, named loniceroside A, C17H26O10, (1), was obtained from the aerial parts of Lonicera saccata. Its structure was established based on an analysis of spectroscopic data, including 1D NMR, 2D NMR and HRESIMS, and the configurations of the chiral C atoms were determined by X-ray crystallographic analysis. The single-crystal structure reveals that the cyclopenta[c]pyran scaffold is formed from a five-membered ring and a chair-like six-membered ring connected through two bridgehead chiral C atoms. In the solid state, the glucose group of (1) plays an important role in constructing an unusual supramolecular motif. The structure analysis revealed adjacent molecules linked together through intermolecular O—H...O hydrogen bonds to generate a banded structure. Furthermore, the banded structures are linked into a three-dimensional network by interesting hydrogen bonds. Biogenetically, compound (1) carries a glucopyranosyloxy moiety at the C-3 position, representing a rare structural feature for naturally occurring iridoid glycosides. The growth inhibitory effects against human cervical carcinoma cells (Hela), human lung adenocarcinoma cells (A549), human acute mononuclear granulocyte leukaemia (THP-1) and the human liver hepatocellular carcinoma cell line (HepG2) were evaluated by the MTT method.
- Published
- 2020
3. Dual-target platinum(IV) complexes exhibit antiproliferative activity through DNA damage and induce ER-stress-mediated apoptosis in A549 cells
- Author
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Chen Yuanhang, Jing Kong, Yanming Wang, Heng-Shan Wang, Yong Yang, Meng Wang, Zhikun Liu, Jin Li, Xu Wang, Chunhao Yu, and Xiaochao Huang
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Organoplatinum Compounds ,DNA damage ,Antineoplastic Agents ,Apoptosis ,01 natural sciences ,Biochemistry ,Ototoxicity ,Drug Discovery ,medicine ,Humans ,Molecular Biology ,Cell Proliferation ,A549 cell ,Cisplatin ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,medicine.disease ,Endoplasmic Reticulum Stress ,0104 chemical sciences ,Oxaliplatin ,010404 medicinal & biomolecular chemistry ,A549 Cells ,Drug Design ,Cancer cell ,Cancer research ,Unfolded protein response ,medicine.drug ,DNA Damage - Abstract
Platinum(II)-based chemotherapeutics are commonly used to treat various types of solid tumors, such as lung cancers. However, these compounds can cause serious side effects, including nephrotoxicity and ototoxicity, which affect the quality of life of patients. In our work, four novel dual target platinum(IV) complexes were designed and synthesized. In vitro results indicated that the title platinum(IV) complexes exhibited effective antitumor activities against the tested cancer cells and had lower toxicity and resistance factors than oxaliplatin and cisplatin. Further mechanistic experiments demonstrated that complex 11 accumulated in mitochondria and induced an elevation in ROS and an ER stress response via mitochondrial dysfunction. Notably, complex 11 significantly modulated the expression levels of proapoptosis proteins including cleaved-Caspase-3, Bax, and p53, and decreased the level of the prosurvival protein Bcl-2. Together, these results suggested that complex 11 might be a potential lead compound for future cancer therapy due to its potency and selectivity.
- Published
- 2020
4. Design, synthesis and structure-activity relationships of novel 15-membered macrolides: Quinolone/quinoline-containing sidechains tethered to the C-6 position of azithromycin acylides
- Author
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Jian Hua Liang, Hiroshi Hiasa, Scott Brody, Bing Zhi Fan, Mark Cushman, Wei Lv, Zhao Yong Yang, and Courtney C. Aldrich
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Methicillin-Resistant Staphylococcus aureus ,medicine.drug_class ,Stereochemistry ,Telithromycin ,Microbial Sensitivity Tests ,Azithromycin ,Quinolones ,medicine.disease_cause ,01 natural sciences ,DNA gyrase ,03 medical and health sciences ,Structure-Activity Relationship ,Drug Discovery ,medicine ,Escherichia coli ,Topoisomerase II Inhibitors ,030304 developmental biology ,Pharmacology ,0303 health sciences ,biology ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Topoisomerase ,Organic Chemistry ,Biological activity ,General Medicine ,Quinolone ,Gatifloxacin ,0104 chemical sciences ,Anti-Bacterial Agents ,DNA Topoisomerases, Type II ,Staphylococcus aureus ,Drug Design ,biology.protein ,Quinolines ,DNA supercoil ,Macrolides ,medicine.drug - Abstract
In the search for novel hybrid molecules by fusing two biologically active scaffolds into one heteromeric chemotype, we found that hybrids of azithromycin and ciprofloxacin/gatifloxacin 26j and 26l can inhibit the supercoiling activity of E. coli gyrase by poisoning it in a way similar to fluoroquinolones. This may modestly contribute to their potencies, which are equal to ciprofloxacin against constitutively resistant Staphylococcus aureus, whose growth is not inhibited by the presence of macrolides. In contrast, introduction of quinolines (the 3-quinoline 26b and the 6-quinoline 26o) with an optimized rigid spacer at the 6-OH of azithromycin acylides did not exert significant potency against constitutively resistant S. aureus, despite the fact that the quinoline-containing compounds, exemplified by 26o, were as active as telithromycin against susceptible, inducibly- and efflux-resistant pathogens. The novel dual modes of action involving protein synthesis inhibition and poisoning DNA replication may pave the way for restoration of antibacterial activities of the current macrolides against constitutively resistant clinical isolates.
- Published
- 2019
5. Discovery of pyridine tetrahydroisoquinoline thiohydantoin derivatives with low blood-brain barrier penetration as the androgen receptor antagonists
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Xijing Chen, Qianming Du, Xi Xu, Jubo Wang, Ying Meng, Zhiyu Li, Yan Li, Hongxi Wu, Zhili Zhao, Jinlei Bian, Raoling Ge, Siqi Xue, Yong Yang, and Xiaoyu Lu
- Subjects
Pyridines ,Mice, Nude ,Antineoplastic Agents ,Inhibitory postsynaptic potential ,01 natural sciences ,03 medical and health sciences ,Prostate cancer ,chemistry.chemical_compound ,Mice ,Structure-Activity Relationship ,Tetrahydroisoquinolines ,LNCaP ,Drug Discovery ,medicine ,Androgen Receptor Antagonists ,Tumor Cells, Cultured ,Enzalutamide ,Animals ,Humans ,030304 developmental biology ,Cell Proliferation ,Pharmacology ,0303 health sciences ,Mice, Inbred BALB C ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Tetrahydroisoquinoline ,Organic Chemistry ,General Medicine ,Neoplasms, Experimental ,medicine.disease ,0104 chemical sciences ,Androgen receptor ,Thiohydantoins ,Blood-Brain Barrier ,Receptors, Androgen ,Toxicity ,Cancer research ,Drug Screening Assays, Antitumor - Abstract
Prostate cancer (PC) is the most diagnosed type of malignancy in men and the major frequently cause of cancer-related death worldwide. The androgen receptor (AR) has become a promising drug target for the treatment of PC. Here, we reported the design, optimization and evaluation of pyridine tetrahydroisoquinoline thiohydantoin derivatives with improved activity and safety as potent AR antagonists. The most promising compound 42f exhibited potent inhibitory activity on AR and strongly blocked AR nuclear translocation. Moreover, 42f displayed promising in vitro antitumor activity toward AR-dependent prostate cancer cell lines (LNCaP) and also demonstrated therapeutic effects in LNCaP xenograft tumor model in mice (TGI: 79%) with no apparent toxicity observed in vivo. More importantly, 42f showed negligible penetration of the brain-blood barrier (BBB) compared with enzalutamide. These results provide a foundation for the development of a new class of androgen receptor antagonists for potential therapeutics against PC with lower seizurogenic risk for patients.
- Published
- 2019
6. Identification of novel androgen receptor degrading agents to treat advanced prostate cancer
- Author
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Zhiyu Li, Jubo Wang, Lulu Zhao, Jie Ren, Yong Yang, Hongxi Wu, Jinlei Bian, and Wanli Ye
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Male ,Cell Survival ,Drug Evaluation, Preclinical ,Antineoplastic Agents ,Apoptosis ,01 natural sciences ,Structure-Activity Relationship ,03 medical and health sciences ,Prostate cancer ,In vivo ,Drug Discovery ,LNCaP ,Androgen Receptor Antagonists ,Tumor Cells, Cultured ,medicine ,Humans ,Mode of action ,Cell Proliferation ,030304 developmental biology ,Flavonoids ,Pharmacology ,Antitumor activity ,0303 health sciences ,Transcriptional activity ,Dose-Response Relationship, Drug ,Molecular Structure ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Prostatic Neoplasms ,General Medicine ,medicine.disease ,0104 chemical sciences ,Androgen receptor ,Androgen dependent ,Receptors, Androgen ,Cancer research ,Drug Screening Assays, Antitumor - Abstract
Prostate cancer (PCa) is one of the most common malignancies affecting men worldwide. Androgen receptor (AR) has been a target of PCa treatment for nearly six decades. AR antagonists/degraders can effectively treat PCa caused by increased AR overexpression. However, all approved AR antagonists have similar chemical structures and exhibit the same mode of action on the protein. Although initially effective, resistance to these AR antagonists usually develops. Therefore, this calls for the identification of novel chemical structures of AR antagonists to overcome the resistance. Herein, we employed the synergetic combination of virtual and experimental screening to identify a flavonoid compound which not only effectively inhibits AR transcriptional activity, but also induces the degradation of the protein. Based on this compound, we designed and synthesized a series of derivatives. We discovered that the most potent compound 10e could effectively inhibit AR transcriptional activity, and possessed a profound ability to cause degradation of both full length- and ARv7 truncated forms of human AR. Notably, 10e efficiently inhibited the growth of ARv7 dependent prostate cancer cell-lines, which are completely resistant to all current anti-androgens. Compound 10e also showed strong antitumor activity in the LNCaP (androgen dependent prostate cancer cell line) in vivo xenograft model. These results provide a foundation for the development of a new class of AR antagonists.
- Published
- 2021
7. A phosphorescent probe for cephalexin consisting of mesoporous thioglycolic acid-modified Mn:ZnS quantum dots coated with a molecularly imprinted polymer
- Author
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Jiang Xiongli, Hao Yang, Yong Yang, Li Yuzhu, Su Xin, Wu Shiwei, Likou Zou, Shujuan Chen, Li He, Xiaolin Ao, and Shuliang Liu
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Materials science ,Polymers ,Surface Properties ,Nanoprobe ,02 engineering and technology ,Sulfides ,01 natural sciences ,Analytical Chemistry ,Molecular Imprinting ,chemistry.chemical_compound ,Quantum Dots ,Thioglycolic acid ,Particle Size ,Detection limit ,Cephalexin ,Manganese ,Luminescent Agents ,Molecular Structure ,010401 analytical chemistry ,Molecularly imprinted polymer ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,chemistry ,Polymerization ,Zinc Compounds ,Thioglycolates ,0210 nano-technology ,Luminescence ,Phosphorescence ,Mesoporous material ,Porosity ,Nuclear chemistry - Abstract
The authors have synthesized a phosphorescent probe of type SiO2-QD-MIP, where QD stands for Mn:ZnS quantum dots and MIP is a polymer coating that was molecularly imprinted with cephalexin. The nanoprobe with high specificity was prepared via sol-gel polymerization using thioglycolic acid (TGA)-modified QDs as luminescent materials, cephalexin as the template, 3-aminopropyltriethoxysilane as the functional monomer, and tetraethoxysilane as the crosslinking agent. The SiO2-QD-MIPs were characterized by X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy, and Fourier transform infrared spectrometry. The orange emission of the probe, with excitation/emission maxima at 295/590 nm, decreases linearly in the 2.5–50 μg·L−1 cephalexin concentration range with a limit of detection (LOD) of 0.81 μg·L−1. The nanoprobe was successfully applied to the determination of cephalexin in (spiked) raw milk and milk powder. The recoveries ranged from 91.7 to 103.7%.
- Published
- 2019
8. Thermodynamic scaling of glassy dynamics and dynamic heterogeneities in metallic glass-forming liquid.
- Author
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Yuan-Chao Hu, Bao-Shuang Shang, Peng-Fei Guan, Yong Yang, Hai-Yang Bai, and Wei-Hua Wang
- Subjects
THERMODYNAMICS ,METALLIC glasses ,FLUCTUATIONS (Physics) ,GLASS transitions ,MOLECULAR structure - Abstract
A ternary metallic glass-forming liquid is found to be not strongly correlating thermodynamically, but its average dynamics, dynamic heterogeneities including the high order dynamic correlation length, and static structure are still well described by thermodynamic scaling with the same scaling exponent γ. This may indicate that the metallic liquid could be treated as a single-parameter liquid. As an intrinsic material constant stemming from the fundamental interatomic interactions, γ is theoretically predicted from the thermodynamic fluctuations of the potential energy and the virial. Although γ is conventionally understood merely from the repulsive part of the inter-particle potentials, the strong correlation between γ and the Grüneisen parameter up to the accuracy of the Dulong-Petit approximation demonstrates the important roles of anharmonicity and attractive force of the interatomic potential in governing glass transition of metallic glassformers. These findings may shed light on how to understand metallic glass formation from the fundamental interatomic interactions. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
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9. Dual-targeting antitumor conjugates derived from platinum(IV) prodrugs and microtubule inhibitor CA-4 significantly exhibited potent ability to overcome cisplatin resistance
- Author
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Meng Wang, Chunhao Yu, Yong Yang, Shaohua Gou, Zhi-Xin Liao, Qinghong You, Heng-Shan Wang, Chun-Gu Wang, Weiwei Hu, and Xiaochao Huang
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Organoplatinum Compounds ,Cell Survival ,Antineoplastic Agents ,Apoptosis ,01 natural sciences ,Biochemistry ,Cell Line, Tumor ,Stilbenes ,Drug Discovery ,medicine ,Humans ,Prodrugs ,MTT assay ,Molecular Biology ,Membrane Potential, Mitochondrial ,chemistry.chemical_classification ,A549 cell ,Cisplatin ,Reactive oxygen species ,Molecular Structure ,010405 organic chemistry ,Organic Chemistry ,Cell Cycle Checkpoints ,Hep G2 Cells ,Prodrug ,Cell cycle ,Tubulin Modulators ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,chemistry ,A549 Cells ,Drug Resistance, Neoplasm ,Cancer cell ,Hepatocytes ,Cancer research ,medicine.drug - Abstract
Here we report that three platinum(IV) prodrugs containing a tubulin inhibitor CA-4, as dual-targeting platinum(IV) prodrug, were synthesized and evaluated for antitumor activity using MTT assay. Among them, complex 9 exhibited the most potent antitumor activity against the tested cancer lines including cisplatin resistance cancer cells, and simultaneously displayed lower toxicity compared to cisplatin, respectively. Moreover, complex 9, in which was conjugated to an inhibitor of tubulin at one axial position of platinum(IV) complex, could effectively enter the cancer cells, and significantly induce cell apoptosis and arrest the cell cycle in A549 cells at G2/M stage, and dramatically disrupt the microtubule organization. In addition, mechanism studies suggested that complex 9 significantly induced reactive oxygen species (ROS) generation and decreased mitochondrial trans-membrane potential (MMP) in A549 cells, and effectively induced activation of caspases triggering apoptotic signaling through mitochondrial dependent apoptosis pathways.
- Published
- 2019
10. Indenoisoquinoline derivatives as topoisomerase I inhibitors that suppress angiogenesis by affecting the HIF signaling pathway
- Author
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Zhiyu Li, Yong Yang, Qidong You, Haopeng Sun, Jian-Min Jia, Xiao-Li Xu, Shengmiao Zhang, Guo Xiaoke, and Fang Liu
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Time Factors ,Zygote ,Angiogenesis ,medicine.medical_treatment ,Neovascularization, Physiologic ,Angiogenesis Inhibitors ,Pharmacology ,Biology ,Topoisomerase-I Inhibitor ,Chorioallantoic Membrane ,chemistry.chemical_compound ,Cell Movement ,In vivo ,Drug Discovery ,Human Umbilical Vein Endothelial Cells ,medicine ,Animals ,Humans ,Cell Proliferation ,Chemotherapy ,Dose-Response Relationship, Drug ,Molecular Structure ,Topoisomerase ,General Medicine ,Hypoxia-Inducible Factor 1, alpha Subunit ,Isoquinolines ,In vitro ,Rats ,Indenes ,chemistry ,Cancer research ,biology.protein ,Topoisomerase I Inhibitors ,Signal transduction ,Chickens ,Lead compound ,Signal Transduction - Abstract
Both Topoisomerase I and angiogenesis factors have caught pharmaceutical chemists’ attention in antitumor chemotherapy field. A series of indenoisoquinoline derivatives with high Top I inhibitory from our previous work were evaluated for their anti-angiogenesis property using classic in vitro and vivo models. The results demonstrated that all the compounds could significantly decrease the proliferation of endothelial cells in a concentration-dependent manner. Besides, compound 1 exerted marked inhibition of angiogenesis in vivo and in vitro models. The HIF signaling pathway in HUVECs was affected by compound 1 in a time-dependent manner. These data suggest that the tested compound 1 could serve as promising lead compound for further development and optimization.
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- 2013
11. C-Lysine Conjugates: pH-Controlled Light-Activated Reagents for Efficient Double-Stranded DNA Cleavage with Implications for Cancer Therapy
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Shauna N. LeGrand, Mani Prabha Singh, Wang Yong Yang, Qing-Xiang Amy Sang, Igor V. Alabugin, Boris Breiner, John A. Copland, Chi Ben, Geoffrey F. Strouse, and Serguei V. Kovalenko
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Models, Molecular ,Light ,Stereochemistry ,Lysine ,Antineoplastic Agents ,Protonation ,Biochemistry ,Article ,Catalysis ,Electron transfer ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Cell Line, Tumor ,Neoplasms ,Humans ,Ammonium ,DNA Cleavage ,Solubility ,Cell Proliferation ,Photolysis ,Molecular Structure ,DNA ,General Chemistry ,Hydrogen-Ion Concentration ,Phosphate ,chemistry ,Intramolecular force ,Plasmids - Abstract
Double-stranded DNA cleavage of light-activated lysine conjugates is strongly enhanced at the slightly acidic pH (7) suitable for selective targeting of cancer cells. This enhancement stems from the presence of two amino groups of different basicities. The first amino group plays an auxiliary role by enhancing solubility and affinity to DNA, whereas the second amino group, which is positioned next to the light-activated DNA cleaver, undergoes protonation at the desired pH threshold. This protonation results in two synergetic effects which account for the increased DNA-cleaving ability at the lower pH. First, lysine conjugates show tighter binding to DNA at the lower pH, which is consistent with the anticipated higher degree of interaction between two positively charged ammonium groups with the negatively charged phosphate backbone of DNA. Second, the unproductive pathway which quenches the excited state of the photocleaver through intramolecular electron transfer is eliminated once the donor amino group next to the chromophore is protonated. Experiments in the presence of traps for diffusing radicals show that reactive oxygen species do not contribute significantly to the mechanism of DNA cleavage at the lower pH, which is indicative of tighter binding to DNA under these conditions. This feature is valuable not only because many solid tumors are hypoxic but also because cleavage which does not depend on diffusing species is more localized and efficient. Sequence-selectivity experiments suggest combination of PET and base alkylation as the chemical basis for the observed DNA damage. The utility of these molecules for phototherapy of cancer is confirmed by the drastic increase in toxicity of five conjugates against cancer cell lines upon photoactivation.
- Published
- 2009
12. Immobilization of homing peptide on magnetite nanoparticles and its specificityin vitro
- Author
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Bing Du, Zhi-Feng Gan, Min Qian, Yong Yang, Ji-Sen Jiang, and Ping Zhang
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Materials science ,Biomedical Engineering ,Nanoparticle ,Peptide ,Sensitivity and Specificity ,Cell Line ,Green fluorescent protein ,Biomaterials ,Magnetics ,Microscopy, Electron, Transmission ,Spectroscopy, Fourier Transform Infrared ,Fluorescence microscope ,Humans ,chemistry.chemical_classification ,Molecular Structure ,Temperature ,Metals and Alloys ,equipment and supplies ,Magnetic hyperthermia ,Microscopy, Fluorescence ,chemistry ,Targeted drug delivery ,Biochemistry ,Ceramics and Composites ,Nanoparticles ,Magnetic nanoparticles ,Peptides ,human activities ,Homing (hematopoietic) - Abstract
As a homing peptide, A54 is the most effective peptide specific to the human hepatocellular carcinoma cell. Homing peptide labeled with green fluorescent protein (A54-GFP) was successfully immobilized on the surfaces of magnetic nanoparticles and characterized by Fourier transform infrared spectroscopy as well as fluorescence microscopy. The binding efficiency was analyzed by performing adsorption equilibrium and SDS-PAGE electrophoresis. Specific binding of the nanoparticles functionalized with A54-GFP to human hepatocellular carcinoma cells in vitro was visualized using fluorescence microscopy. The results demonstrated the specificity of A54-GFP-coated magnetic nanoparticle to tumor cell, pointing to its great potential in magnetic cell separation and purification, magnetic resonance imaging (MRI), magnetic hyperthermia, and drug targeting.
- Published
- 2008
13. A Helix−Turn−Helix Supersecondary Structure Based on Oligo(phenanthroline dicarboxamide)s
- Author
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Junfeng Xiang, Yong Yang, Hai-Yu Hu, and Chuan-Feng Chen
- Subjects
Models, Molecular ,Magnetic Resonance Spectroscopy ,Molecular Structure ,Stereochemistry ,Phenanthroline ,Organic Chemistry ,Molecular Conformation ,Helix-turn-helix ,Nuclear magnetic resonance spectroscopy ,Crystallography, X-Ray ,Amides ,Biochemistry ,Turn (biochemistry) ,chemistry.chemical_compound ,chemistry ,Diamine ,Helix ,Spectrophotometry, Ultraviolet ,Supersecondary structure ,Physical and Theoretical Chemistry ,Alpha helix ,Helix-Turn-Helix Motifs ,Phenanthrolines - Abstract
An artificial helix-turn-helix (HTH) supersecondary structure based on the oligo(phenanthroline dicarboxamide)s, in which the 2,2'-dimethoxy-1,1'-binaphthyl-6,6'-diamine subunit was utilized as the turn to impart a bias in the twist sense of the supersecondary structure, was reported. The HTH structure has been demonstrated by UV/vis, NMR, CD spectra, and X-ray crystal analysis.
- Published
- 2007
14. Quadruply Hydrogen-Bonded Building Block from Hydrazide−Quinolinone Motif and Gelation Ability of Its Analogous Oxalic Monoester−Monoamide Derivative
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Chuan-Feng Chen, Yong Yang, Li-Jun Wan, and Hui-Juan Yan
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Magnetic Resonance Spectroscopy ,Molecular Structure ,Hydrogen ,Stereochemistry ,Organic Chemistry ,chemistry.chemical_element ,Esters ,Hydrogen Bonding ,Quinolones ,Block (periodic table) ,Hydrazide ,Amides ,Biochemistry ,Hexane ,chemistry.chemical_compound ,chemistry ,Microscopy, Scanning Tunneling ,Polymer chemistry ,Particle Size ,Physical and Theoretical Chemistry ,Gels ,Derivative (chemistry) ,Dichloromethane - Abstract
NMR and STM studies revealed that the hydrazide-quinolinone-based building block 5 exhibited a monomer-dimer-polymer equilibrium, while its acyclic analogue 6, due to conformational flexibility, exhibited a more complicated mode of aggregation and formed a gel in dichloromethane/hexane.
- Published
- 2007
15. Enantioselective 1,3-Dipolar Cycloaddition of Cyclic Enones Catalyzed by Multifunctional Primary Amines: Beneficial Effects of Hydrogen Bonding
- Author
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Yong-Zheng Duan, Ying-Chun Chen, Wei Du, Yong Wu, Wei Chen, and Sheng-Yong Yang
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Models, Molecular ,Thiosemicarbazones ,Primary (chemistry) ,Molecular Structure ,Chemistry ,Enantioselective synthesis ,Hydrogen Bonding ,Stereoisomerism ,General Medicine ,General Chemistry ,Crystallography, X-Ray ,Catalysis ,Cycloaddition ,chemistry.chemical_compound ,Cyclization ,Heterocyclic Compounds ,Organocatalysis ,1,3-Dipolar cycloaddition ,Organic chemistry ,Amine gas treating ,Imines ,Amines ,Azo Compounds ,Enone - Published
- 2007
16. Phosphorylation-directed assembly of a single quantum dot based nanosensor for protein kinase assay
- Author
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Yong Yang, Li-juan Wang, and Chun-yang Zhang
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Analytical Chemistry ,chemistry.chemical_compound ,Structure-Activity Relationship ,Biotin ,Quantum Dots ,Fluorescence Resonance Energy Transfer ,Tumor Cells, Cultured ,Humans ,Nanotechnology ,Phosphorylation ,Protein kinase A ,Protein Kinase Inhibitors ,Enzyme Assays ,Sulfonamides ,Dose-Response Relationship, Drug ,Molecular Structure ,Kinase ,Carbocyanines ,Isoquinolines ,Intracellular signal transduction ,Förster resonance energy transfer ,chemistry ,Biochemistry ,Biotinylation ,Adenosine triphosphate ,Protein Kinases ,HeLa Cells - Abstract
Protein kinases play crucial roles in intracellular signal transduction and metabolic pathways, and the monitoring of protein kinase activity is essential to the understanding of fundamental biochemical processes and the clinical diagnosis. Here, we demonstrate the phosphorylation-directed assembly of a single quantum dot (QD)-based nanosensor for sensitive detection of cAMP-dependent protein kinase (PKA). This assay involves (1) the PKA-directed simultaneous phosphorylation and biotinylation of cyanine 5 (Cy5)-labeled substrate peptides, (2) the assembly of phosphorylated and biotinylated peptides onto the surface of the QD, and (3) the illumination of Cy5 by means of fluorescence resonance energy transfer (FRET) between the QD and Cy5. With an adenosine triphosphate (ATP) analogue, γ-biotin-ATP, as the phosphoryl donor, the PKA-catalyzed phosphorylation reaction incorporates the biotin-conjugated phosphate group into the substrate peptides to form the biotinylated peptides. The biotin entity subsequently drives the assembly of peptides onto the surface of streptavidin-functionalized QD to form the sandwiched Cy5-peptide-QD nanostructure, enabling the occurrence of FRET between the QD and Cy5. The FRET signal can be easily recorded by either the conventional fluorescence spectrometer or the total internal reflection fluorescence (TIRF) microscope. In contrast, the absence of PKA cannot lead to the formation of Cy5-peptide-QD complex and no Cy5 signal can be detected. This protein kinase-actuated FRET assay is straightforward, without the involvement of either washing or separation steps, and has a significant advantage of high sensitivity with a detection limit of 9.3 × 10(-6) U/μL. Moreover, this method can be used to estimate the half-maximal inhibitory concentration (IC50) value of PKA inhibitor H-89 (N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride) and to monitor forskolin (Fsk)/3-isobutyl-1-methylxanthine (IBMX)-triggered activation of PKA in cell lysates, thus holding great potential for further applications in protein kinase-related biological researches and drug discovery.
- Published
- 2015
17. Effect of ultrasound treatment on the wet heating Maillard reaction between mung bean [Vigna radiate (L.)] protein isolates and glucose and on structural and physico-chemical properties of conjugates
- Author
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Zhongjiang, Wang, Feifei, Han, Xiaonan, Sui, Baokun, Qi, Yong, Yang, Hui, Zhang, Rui, Wang, Yang, Li, and Lianzhou, Jiang
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Glucose ,Glycosylation ,Hot Temperature ,Chemical Phenomena ,Molecular Structure ,Solubility ,Emulsifying Agents ,Vigna ,Ultrasonics ,Hydrophobic and Hydrophilic Interactions ,Maillard Reaction ,Plant Proteins - Abstract
The objective of this study was to determine the effect of ultrasound treatment on the wet heating Maillard reaction between mung bean protein isolates (MBPIs) and glucose, and on structural and physico-chemical properties of the conjugates.The degree of glycosylation of MBPI-glucose conjugates treated by ultrasound treatment and wet heating (MBPI-GUH) was higher than that of MBPI-glucose conjugates only treated by wet heating (MBPI-GH). Solubility, emulsification activity, emulsification stability and surface hydrophobicity of MBPI-GUH were higher than that of MBPI-GH. Grafted MBPIs had a lower content of α-helix and unordered coil, but a higher content of β-sheet and β-turn structure than MBPIs. No significant structural changes were observed in β-turn and random coil structure of MBPI-GUH, while α-helix content increased with ultrasonic time, and decreased at 300 W ultrasonic power with the increase of β-sheet. MBPI-GUH had a less compact tertiary structure compared to MBPI-GH and MBPI. Grafting MBPIs with glucose formed conjugates of higher molecular weight, while no significant changes were observed in electrophoresis profiles of MBPI-GUH.Ultrasound-assisted wet heating Maillard reaction between MBPIs and glucose could be a promising way to improve functional properties of MBPIs.
- Published
- 2015
18. The Anticancer Activities of Wogonin in Murine Sarcoma S180 both in Vitro and in Vivo
- Author
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Xiaotang Wang, Kun Zhang, Yang Hu, Yong Yang, Wei Liu, Hong-Yan Gu, Qinglong Guo, Zi Tan, Jun Yu, Qidong You, Li Zhao, and Wei Wang
- Subjects
Male ,Blotting, Western ,Pharmaceutical Science ,Apoptosis ,DNA Fragmentation ,Biology ,Leukocyte Count ,Mice ,chemistry.chemical_compound ,Wogonin ,In vivo ,Cell Line, Tumor ,Leukocytes ,Animals ,MTT assay ,Sarcoma 180 ,IC50 ,Pharmacology ,Mice, Inbred ICR ,Dose-Response Relationship, Drug ,Molecular Structure ,Reverse Transcriptase Polymerase Chain Reaction ,General Medicine ,Antineoplastic Agents, Phytogenic ,Molecular biology ,In vitro ,chemistry ,Cell culture ,Flavanones ,DNA fragmentation ,Female ,Neoplasm Transplantation ,Drugs, Chinese Herbal ,Scutellaria baicalensis - Abstract
The anticancer effects of wogonin on murine sarcoma S180 both in vitro and in vivo were investigated, and its pro-apoptotic molecular mechanism was further studied. Wogonin treatment resulted in significant inhibition of S180 cells in a concentration-dependent manner detected by MTT assay. The IC50 value for 48 h was (7.37+/-1.53) x 10(-5) M. Typical morphological changes and apoptosis bleb phenomenon in S180 cells exposed to wogonin were distinctly observed by the inverted light microscope and the fluorescence microscope, respectively. According to protocols of transplanted tumor research, mice were transplanted with tumor cells S180. The weight of tumor and the peripheral leucocyte count were observed after the treatment of wogonin. The significant suppression of tumor growth was observed, and the peripheral leucocyte count of S180-bearing mice remained no significant changes compared with control group. After the treatment of 40 mg/kg wogonin, the inhibitory rate of tumor weight was 53.01%. Additional DNA fragmentation assay showed that wogonin induced apoptosis on murine sarcoma S180 tissue. RT-PCR results indicated that the increasing mRNA levels of bax and p53 and the decreasing mRNA level of bcl-2 were induced by wogonin. Western-blot assay showed that the increasing protein level of bax and the decreasing protein level of bcl-2 were induced by wogonin. Collectively, wogonin could induce apoptosis in murine sarcoma S180 thereby inhibiting the tumor growth both in vitro and in vivo. The pro-apoptotic effects might be related to the improvement of mRNA level of p53, the improvement of mRNA and protein levels of bax, and the reduction of mRNA and protein levels of bcl-2.
- Published
- 2006
19. Copolymerization of Ethylene with Polar Monomers: Chain Propagation and Side Reactions. A DFT Theoretical Study Using Zwitterionic Ni(II) and Pd(II) Catalysts
- Author
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Laurent F. Groux, Sheng-Yong Yang, Warren E. Piers, Miklos J. Szabo, Tom Ziegler, Artur Michalak, and Natasha M. Galea
- Subjects
Chain propagation ,Ethylene ,Biochemistry ,Catalysis ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,Nickel ,Polymer chemistry ,Organometallic Compounds ,Copolymer ,Organic chemistry ,Diimine ,Acrylonitrile ,Molecular Structure ,Chemistry ,Aryl ,Cationic polymerization ,Stereoisomerism ,General Chemistry ,Ethylenes ,Kinetics ,Models, Chemical ,Oxidation-Reduction ,Palladium - Abstract
Calculations utilizing anionic substituted derivates of the cationic N(wedge)N--Ni(II) and Pd(II) diimine Brookhart complex have been carried out on the barriers of ethylene and acrylonitrile insertion into a M- methyl, propyl and CH(CN)Et bond for M = Ni, Pd. The possibility of side reactions such as chelate formation with the polar functionality and oligomerization of the active species after acrylonitrile insertion are explored. The diimine ring system N--N = -NR' 'CR(1)CR(2)NR' ' with R' ' = 2,6-C(6)H(3)(i-Pr)(2) and R(1),R(2) = Me was functionalized by adding one or two anionic groups (BF(3)(-), etc.) in place of i-Pr on the aryl rings or by replacing one Me diimine backbone group (R(1)) with BH(3)(-). The objective of this investigation is computationally to design catalysts for ethylene/acrylonitrile copolymerization that have activities that are comparable to that of the cationic Ni(II) diimine or at least the Pd(II) diimine Brookhart system for ethylene homopolymerization. Complexes that might meet this objective are discussed.
- Published
- 2005
20. Ternary copper(II) complexes with amino acid chains and heterocyclic bases: DNA binding, cytotoxic and cell apoptosis induction properties
- Author
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Zhijun Ge, Yang Liu, Hao Yu, Taofeng Zhu, Tieliang Ma, Ruhua Chen, Lei Jia, Weiliang Ding, Yong Yang, Yuan Wang, Jun Xu, Yongfei Tan, and Wenjiao Zhu
- Subjects
Models, Molecular ,Stereochemistry ,Phenazine ,chemistry.chemical_element ,Antineoplastic Agents ,Apoptosis ,Biochemistry ,Inorganic Chemistry ,chemistry.chemical_compound ,Inhibitory Concentration 50 ,Quinoxaline ,Bromide ,Coordination Complexes ,Cell Line, Tumor ,Animals ,Humans ,Schiff Bases ,Schiff base ,Molecular Structure ,Ligand ,DNA ,Copper ,chemistry ,Phenazines ,Cattle ,Ethidium bromide ,Phenanthrolines - Abstract
Nowadays, chemotherapy is a common means of oncology. However, it is difficult to find excellent chemotherapy drugs. Here we reported three new ternary copper(II) complexes which have potential chemotherapy characteristics with reduced Schiff base ligand and heterocyclic bases (TBHP), [Cu(phen)(TBHP)]H2O (1), [Cu(dpz)(TBHP)]H2O (2) and [Cu(dppz)(TBHP)]H2O (3) (phen=1,10-phenanthroline, dpz=dipyrido [3,2:2',3'-f]quinoxaline, dppz=dipyrido [3,2-a:2',3'-c]phenazine, H2TBHP=2-(3,5-di-tert-butyl-2-hydroxybenzylamino)-2-benzyl-acetic acid). The DNA-binding properties of the complexes were investigated by spectrometric titrations, ethidium bromide displacement experiments and viscosity measurements. The results indicated that the three complexes, especially the complex 13, can strongly bind to calf-thymus DNA (CT-DNA). The intrinsic binding constants Kb of the ternary copper(II) complexes with CT-DNA were 1.37×10(5), 1.81×10(5) and 3.21×10(5) for 1, 2 and 3 respectively. Comparative cytotoxic activities of the copper(II) complexes were also determined by 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results showed that the ternary copper(II) complexes had significant cytotoxic activity against the human lung cancer (A549), human esophageal cancer (Eca109) and human gastric cancer (SGC7901) cell lines. Cell apoptosis were detected by AnnexinV/PI flow cytometry and by Western blotting with the protein expression of p53, Bax and Bcl-2. All the three copper complexes can effectively induce apoptosis of the three human tumor cells.
- Published
- 2014
21. Nickel complex with internal bases as efficient molecular catalyst for photochemical H2 production
- Author
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Fengbo Zhang, Lin Chen, Mei Wang, Yong Yang, Licheng Sun, Liqin Xue, and Mårten S. G. Ahlquist
- Subjects
Base (chemistry) ,Hydrogen ,Photochemistry ,Pyridines ,General Chemical Engineering ,chemistry.chemical_element ,Molecular Dynamics Simulation ,Electrochemistry ,Crystallography, X-Ray ,Mass Spectrometry ,Catalysis ,chemistry.chemical_compound ,Nickel ,Spectroscopy, Fourier Transform Infrared ,Organometallic Compounds ,Environmental Chemistry ,General Materials Science ,chemistry.chemical_classification ,Quenching (fluorescence) ,Molecular Structure ,Quinoline ,Turnover number ,General Energy ,Spectrometry, Fluorescence ,chemistry ,Quinolines - Abstract
A Ni complex with internal bases that contain bipyridine-derived ligands, [Ni(L)2 (H2 O)2 ](BF4 )2 ([1](BF4 )2 , L=2-(2-pyridyl)-1,8-naphthyridine), and a reference complex that bears analogous bipyridine-derived ligands but without an internal base, [Ni(L')3 ](BF4 )2 ([2](BF4 )2 , L'=2-(2-pyridyl)quinoline), were synthesized and characterized. The electrochemical properties of these complexes were studied in CH3 CN, H2 O, and a mixture of EtOH/H2 O. The fluorescence spectroscopic studies suggest that both dynamic and the sphere-of-action static quenching exist in the fluorescein Fl(2-) /[1](2+) and Fl(2-) /[2](2+) systems. These noble-metal-free molecular systems were studied for photocatalytic H2 generation. Under optimal conditions, the turnover number of H2 evolution reaches 3230 based on [1](2+) , whereas [2](2+) displays only approximately one third of the turnover of [1](2+) . A plausible mechanism for the catalytic H2 generation by [1](2+) is presented based on DFT calculations.
- Published
- 2014
22. [Identification of tetracenomycin X from a marine-derived Saccharothrix sp. guided by genes sequence analysis]
- Author
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Bin, Liu, Yi, Tan, Mao-Luo, Gan, Hong-Xia, Zhou, Yi-Guang, Wang, Yu-Hui, Ping, Bin, Li, Zhao-Yong, Yang, and Chun-Ling, Xiao
- Subjects
Methicillin-Resistant Staphylococcus aureus ,Benzodiazepinones ,Molecular Structure ,Naphthacenes ,Antineoplastic Agents ,Marine Biology ,Genomics ,Microbial Sensitivity Tests ,Anti-Bacterial Agents ,Inhibitory Concentration 50 ,Cell Line, Tumor ,Actinomycetales ,Drug Resistance, Bacterial ,Fermentation ,Enterococcus faecalis ,Staphylococcus epidermidis ,Data Mining ,Humans ,Phylogeny - Abstract
The crude extracts of the fermentation broth from a marine sediment-derived actinomycete strain, Saccharothrix sp. 10-10, showed significant antibacterial activities against drug-resistant pathogens. A genome-mining PCR-based experiment targeting the genes encoding key enzymes involved in the biosynthesis of secondary metabolites indicated that the strain 10-10 showed the potential to produce tetracenomycin-like compounds. Further chemical investigation of the cultures of this strain led to the identification of two antibiotics, including a tetracenomycin (Tcm) analogs, Tcm X (1), and a tomaymycin derivative, oxotomaymycin (2). Their structures were identified by spectroscopic data analysis, including UV, 1D-NMR, 2D-NMR and MS spectra. Tcm X (1) showed moderate antibacterial activities against a number of drug-resistant pathogens, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) pathogens, with the MIC values in the range of 32-64 microg x mL(-1). In addition, 1 also displayed significant cytotoxic activities against human cancer cell lines, including HL60 (leukemia), HepG2 (liver), and MCF-7 (breast) with the IC 50 values of 5.1, 9.7 and 18.0 micromol x L(-1), respectively. Guided by the PCR-based gene sequence analysis, Tcm X (1) and oxotomaymycin (2) were identified from the genus of Saccharothrix and their 13C NMR data were correctly assigned on the basis of 2D NMR spectroscopic data analysis for the first time.
- Published
- 2014
23. [Halogenated natural products from the marine-derived actinobacteria and their halogenation mechanism]
- Author
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Yi, Tan, Hong-xia, Zhou, Yi-guang, Wang, Mao-luo, Gan, and Zhao-yong, Yang
- Subjects
Actinobacteria ,Biological Products ,Halogenation ,Molecular Structure ,Cell Line, Tumor ,Humans ,Antineoplastic Agents ,Marine Biology ,Anti-Bacterial Agents ,Cell Proliferation - Abstract
In the last decade, along with the development of taxonomy research in marine-derived actinobacteria, more and more halogenated natural products were discovered from marine actinobacteria. Most of them showed good biological activity and unique structure compared to those from land. The special halogenation mechanism in some compounds' biosynthesis has drawn great attention. So in this review, we focus on the halogenated natural products from marine actinobacteria and their halogenation mechanisms.
- Published
- 2013
24. Helical molecular duplex strands: multiple hydrogen-bond-mediated assembly of self-complementary oligomeric hydrazide derivatives
- Author
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Zhi-Yong Yang, Li-Jun Wan, Yuanping Yi, Zhigang Shuai, Yong Yang, Chuan-Feng Chen, and Junfeng Xiang
- Subjects
Microscopy, Electron, Scanning Transmission ,Models, Molecular ,Magnetic Resonance Spectroscopy ,Molecular Structure ,Spectrophotometry, Infrared ,Stereochemistry ,Hydrogen bond ,Organic Chemistry ,Hydrogen Bonding ,Hydrazide ,Oligomer ,chemistry.chemical_compound ,Monomer ,Hydrazines ,chemistry ,Tetramer ,Duplex (building) ,Molecule ,Self-assembly - Abstract
Careful examination of the X-ray structure of a ditopic hydrazide derivative 7 led to the concept that with malonyl groups as interhydrazide linkers hydrogen-bonding-mediated molecular duplex strands might be obtained. Complexation studies between 7, 8, and 9 confirmed this hypothesis. Two quadruple hydrogen-bonded heterodimers formed, in which spectator repulsive secondary electrostatic interaction was found to play an important role in determining the stability of the complexes. Extensive studies on 1-4 indicated that the hydrogen-bonding mode could persist in longer oligomeric hydrazide derivatives with chain extension from monomer to tetramer. Molecular duplex strands via two to fourteen interstrand hydrogen bonds were obtained. In addition to affecting the stability of the duplex strands, spectator repulsive secondary electrostatic interaction also played an important role in determining dynamic behavior of the duplex strands as exemplified by variable temperature (1)H NMR experiments. IR studies confirmed stronger hydrogen bonding in the longer oligomers. The assemblies of 1-4 on HOPG were also studied by STM technology. Molecular mechanical calculations further revealed double-helical structures for the longer oligomers. The results provide new opportunities for development of polymeric helical duplexes with well-defined structures.
- Published
- 2007
25. Effective Nonenzymatic Kinetic Resolution of Racemic m-Nitro-Substituted Inherently Chiral Aminocalix[4]arenes
- Author
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Zhen-Xiang Xu, Yong Yang, Zhi-Tang Huang, Chun Zhang, and Chuan-Feng Chen
- Subjects
Molecular Structure ,Proline ,Chemistry ,Organic Chemistry ,Enantioselective synthesis ,Stereoisomerism ,Nitro Compounds ,Biochemistry ,Catalysis ,Kinetic resolution ,Kinetics ,Reagent ,Nitro ,Organic chemistry ,Calixarenes ,Physical and Theoretical Chemistry ,Aminocalix - Abstract
Effective nonenzymatic kinetic resolution of racemic m-nitro-substituted inherently chiral aminocalix[4]arenes with Boc-l-proline as the acylating reagent is described, which provides an efficient and convenient method for the enantioselective synthesis of meta-substituted aminocalix[4]arenes.
- Published
- 2008
26. [Glycosyl isomerization based on the biosynthesis of natural-product sugar from microorganism]
- Author
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Wan, Sun, Hai-Feng, Li, Jing, Chen, Guo-Jun, Wang, and Zhao-Yong, Yang
- Subjects
Biological Products ,Glycosylation ,Isomerism ,Molecular Structure ,Carbohydrates ,Glycosyltransferases ,Anthraquinones ,Synthetic Biology ,Streptomyces ,Erythromycin ,Saccharopolyspora - Abstract
Glycosylation, one of the most common and important reactions in biological systems, results in diverse functions and is often found in biologically active small-molecule natural products produced by microorganisms. Furthermore, sugar moieties are generally critical for their activities. Alternating the sugar structures thus provides the potentials for enhancing the biological activities of natural products, which evokes researchers to study the sugar biosynthetic machinery and its application in the modification of sugar moieties with an aim of generating unnaturally glycosylated natural product drugs with better activities. This review will briefly outline current studies on sugar biosynthesis and glycosyltransferase, with a few selected experiments designed to alter natural-product sugar structures.
- Published
- 2013
27. Structural optimization and structure-activity relationships of N2-(4-(4-Methylpiperazin-1-yl)phenyl)-N8-phenyl-9H-purine-2,8-diamine derivatives, a new class of reversible kinase inhibitors targeting both EGFR-activating and resistance mutations
- Author
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Jiao, Yang, Li-Jiao, Wang, Jing-Jing, Liu, Lei, Zhong, Ren-Lin, Zheng, Yong, Xu, Pan, Ji, Chun-Hui, Zhang, Wen-Jing, Wang, Xing-Dong, Lin, Lin-Li, Li, Yu-Quan, Wei, and Sheng-Yong, Yang
- Subjects
Models, Molecular ,Spectrometry, Mass, Electrospray Ionization ,Magnetic Resonance Spectroscopy ,Molecular Structure ,Immunohistochemistry ,Piperazines ,Cell Line ,ErbB Receptors ,Molecular Docking Simulation ,Structure-Activity Relationship ,Drug Resistance, Neoplasm ,Purines ,Cell Line, Tumor ,Mutation ,Humans ,Protein Kinase Inhibitors - Abstract
This paper describe the structural optimization of a hit compound, N2-(4-(4-methylpiperazin-1-yl)phenyl)-N8-phenyl-9H-purine-2,8-diamine (1), which is a reversible kinase inhibitor targeting both EGFR-activating and drug-resistance (T790M) mutations but has poor binding affinity. Structure-activity relationship studies led to the identification of 9-cyclopentyl-N2-(4-(4-methylpiperazin-1-yl)phenyl)-N8-phenyl-9H-purine-2,8-diamine (9e) that exhibits significant in vitro antitumor potency against the non-small-cell lung cancer (NSCLC) cell lines HCC827 and H1975, which harbor EGFR-activating and drug-resistance mutations, respectively. Compound 9e was further assessed for potency and selectivity in enzymatic assays and in vivo anti-NSCLC studies. The results indicated that compound 9e is a highly potent kinase inhibitor against both EGFR-activating and resistance mutations and has good kinase spectrum selectivity across the kinome. In vivo, oral administration of compound 9e at a dose of 5 mg/kg caused rapid and complete tumor regression in a HCC827 xenograft model, and an oral dose of 50 mg/kg initiated a considerable antitumor effect in an H1975 xenograft model.
- Published
- 2012
28. Photocatalytic oxidation of indoor toluene: process risk analysis and influence of relative humidity, photocatalysts, and VUV irradiation
- Author
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Jiusong Dai, Dongye Zhao, Yong Yang, Weirong Zhao, Yan Wang, Feifei Liu, Jiaze Bao, and Yanan Yang
- Subjects
Environmental Engineering ,Ultraviolet Rays ,Radical ,Photochemistry ,Chemical reaction ,Risk Assessment ,Catalysis ,Mass Spectrometry ,chemistry.chemical_compound ,Desorption ,Environmental Chemistry ,Waste Management and Disposal ,Air Pollutants ,Molecular Structure ,Chemistry ,Electron Spin Resonance Spectroscopy ,Temperature ,Humidity ,Mineralization (soil science) ,Photochemical Processes ,Pollution ,Toluene ,Air Pollution, Indoor ,Photocatalysis ,Hydroxide ,Oxidation-Reduction - Abstract
Concentrations of 13 gaseous intermediates in photocatalytic oxidation (PCO) of toluene in indoor air were determined in real-time by proton transfer reaction mass spectrometry and desorption intensities of 7 adsorbed intermediates on the surface of photocatalysts were detected by temperature‐programmed desorption‐mass spectrometry. Effects of relative humidity (RH), photocatalysts, and vacuum ultraviolet (VUV) irradiation on the distribution and category of the intermediates and health risk influence index ( η ) were investigated. RH enhances the formation rate of hydroxide radicals, leading to more intermediates with higher oxidation states in gas phase. N doping promotes the separation of photo-generated electrons and holes and enhances PCO activity accordingly. VUV irradiation results in higher mineralization rate and more intermediates with higher oxidation states and lower toxicity e.g. carboxylic acids. Health risk analysis indicates that higher RH, N doping of TiO 2 , and VUV lead to “greener” intermediates and smaller η . Finally, a conceptual diagram was proposed to exhibit the scenario of η varied with extent of mineralization for various toxicities of inlet pollutants.
- Published
- 2012
29. Part II: Design, synthesis and antitumor action of C3/C3 bisfluoroquinolones linked-cross 2, 5-[1, 3, 4]oxadiazole
- Author
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Guo-qiang, Hu, Yong, Yang, Lei, Yi, Xin, Wang, Zhi-qiang, Zhang, Song-qiang, Xie, and Wen-long, Huang
- Subjects
Oxadiazoles ,Molecular Structure ,Antineoplastic Agents ,HL-60 Cells ,CHO Cells ,Inhibitory Concentration 50 ,Structure-Activity Relationship ,Cricetulus ,Cell Line, Tumor ,Cricetinae ,Drug Design ,Animals ,Humans ,Leukemia L1210 ,Fluoroquinolones - Abstract
To develop a new small molecular probe for discovering an antitumor lead compound from the replacement of carboxylic group of two molecular antibacterial fluoroquinolones with a heterocyclic ring, a series of the C3/C3 bis-fluoroquinolones tethered with an 1, 3, 4-oxadiazole ring were synthesized as their respective HCl salts, and their structures were characterized by elemental analysis and spectral data. The in vitro antitumor activity against L1210, CHO and HL60 cell lines was also evaluated via the respective IC50 values by methylthiazole trazolium (MTT) assay.
- Published
- 2011
30. Advances in machine learning prediction of toxicological properties and adverse drug reactions of pharmaceutical agents
- Author
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Z. R. Li, Yin Xue, Xiao Hua Ma, Yu Quan Wei, Rong Wang, Sheng Yong Yang, and Yu Zong Chen
- Subjects
Models, Molecular ,Toxicology ,Machine learning ,computer.software_genre ,Decision Support Techniques ,Structure-Activity Relationship ,Artificial Intelligence ,Toxicity Tests ,Medicine ,Animals ,Humans ,Pharmacology (medical) ,Computer Simulation ,Drug reaction ,Pharmacology ,Molecular Structure ,business.industry ,Drug discovery ,Decision Trees ,Reproducibility of Results ,Bayes Theorem ,Logistic Models ,Artificial intelligence ,Neural Networks, Computer ,business ,computer - Abstract
As part of the intensive efforts in facilitating drug discovery, computational methods have been explored as low-cost and efficient tools for predicting various toxicological properties and adverse drug reactions (ADR) of pharmaceutical agents. More recently, machine learning methods have been applied for developing tools capable of predicting diverse spectrum of compounds of different toxicological properties and ADR profiles. Based on the results of a number of studies, these methods have shown promising potential in predicting a variety of toxicological properties and ADR profiles. This article reviews the strategies, current progresses, underlying difficulties and future prospects in using machine learning methods for predicting compounds of specific toxicological property or ADR profile.
- Published
- 2008
31. [Progress in the design of selective ATP-competitive kinase inhibitors]
- Author
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Xiao-qiang, Deng, Ming-li, Xiang, Ruo, Jia, and Sheng-yong, Yang
- Subjects
Adenosine Triphosphate ,Molecular Structure ,Drug Design ,Binding, Competitive ,Protein Kinase Inhibitors ,Protein Binding - Abstract
Kinases play crucial roles in the life of cell. Their functional abnormity usually leads to many human major diseases including tumors. The prospecting of ATP-competitive small-molecule kinase inhibitors targeting kinases of therapeutic interest has become the focus of researches. Due to the high conservation of the catalytic domain of kinases, the selectivity of kinase inhibitors is poor in general. However, along with the development of structural biology and computer-aided drug design, great progress in the research of selective, ATP-competitive kinase inhibitors has been achieved in recent years. In this account, the review has been made on the development of the design of selective kinase inhibitors.
- Published
- 2008
32. Reinioside C, a triterpene saponin of Polygala aureocauda Dunn, exerts hypolipidemic effect on hyperlipidemic mice
- Author
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Yong Yang, Dan-Ni Zhu, Qiu-Juan Wang, and Hao Li
- Subjects
Male ,Polygala ,Myocytes, Smooth Muscle ,Saponin ,Hyperlipidemias ,Pharmacology ,Umbilical vein ,Superoxide dismutase ,chemistry.chemical_compound ,Mice ,In vivo ,Malondialdehyde ,Animals ,Cells, Cultured ,Triglycerides ,Cell Proliferation ,Hypolipidemic Agents ,chemistry.chemical_classification ,biology ,Molecular Structure ,Cholesterol ,Superoxide Dismutase ,Endothelial Cells ,Cholesterol, LDL ,Saponins ,Triterpenes ,Lipoproteins, LDL ,chemistry ,Biochemistry ,Liver ,biology.protein ,Cholesteryl ester ,Macrophages, Peritoneal ,lipids (amino acids, peptides, and proteins) ,Calcium ,Lipoprotein - Abstract
Reinioside C is a triterpene saponin from the the root of Polygala aureocauda Dunn (PAD). This study examined the effects of reinioside C on hyperlipidemic mice in vivo and endothelium cells, macrophages and smooth muscle cells in vitro. Mice were given a hyperlipidemic diet for 30 days, then administered reinioside C (4, 8, 16 mg/kg/day, p.o.) for 30 days. Then the serum lipid, superoxide dismutase (SOD), malonaldehyde (MDA), the total cholesterol (TC) and triglyceride (TG) in the liver extract were measured. Human umbilical vein endothelial (HUVECs), peritoneal macrophages and smooth muscle cells (SMCs) pre-treated with reinioside C were treated with oxidized low-density lipoprotein (OxLDL). The results showed that reinioside C decreased serum and liver tissue lipid profiles in hyperlipidemic mice. Moreover, reinioside C protected the HUVECs against the Ox-LDL induced LDH leakage and exerted a protective effect on oxidative lesions induced by OxLDL, inhibited cholesteryl ester accumulation in macrophages, and decreased [Ca2+](i) and SMC proliferation in vitro. Based on these results, it is suggested that reinioside C is a promising hypolipidemic candidate.
- Published
- 2008
33. Dynamic decomposition/recombination of hydrogen bonds in molecular duplex strands
- Author
-
and Jun-Feng Xiang, Yong Yang, and Chuan-Feng Chen
- Subjects
Models, Molecular ,Magnetic Resonance Spectroscopy ,Molecular Structure ,Hydrogen bond ,Organic Chemistry ,Degenerate energy levels ,Hydrogen Bonding ,DNA ,Hydrazide ,Biochemistry ,chemistry.chemical_compound ,Crystallography ,chemistry ,Duplex (building) ,Proton NMR ,Molecule ,Thermodynamics ,Physical and Theoretical Chemistry ,Recombination - Abstract
Dynamic decomposition/recombination of hydrogen bonds in the hydrazide based molecular duplex strands was explored by variable-temperature 1H NMR experiments. A shuttle-like dynamic process of the two constituent molecules of the duplex strands between two degenerate states was observed.
- Published
- 2007
34. Hybrids of amino acids and acetylenic DNA-photocleavers: optimising efficiency and selectivity for cancer phototherapy
- Author
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Wang Yong Yang, Saumya Roy, Kemal Kaya, Igor V. Alabugin, and Boris Breiner
- Subjects
Models, Molecular ,Cell ,Biochemistry ,chemistry.chemical_compound ,Cell Line, Tumor ,Neoplasms ,medicine ,Humans ,Amino Acids ,Physical and Theoretical Chemistry ,Cell Proliferation ,chemistry.chemical_classification ,Molecular Structure ,Cell growth ,Organic Chemistry ,Acetylation ,DNA ,Hydrogen-Ion Concentration ,Photochemical Processes ,Cell Hypoxia ,In vitro ,Amino acid ,medicine.anatomical_structure ,chemistry ,Cyclization ,Cell culture ,Cancer cell - Abstract
Hybrid agents which combine potent DNA-photocleavers with tunable amino acids or small peptides were designed to improve selectivity of Nature's most potent class of antibiotics towards cancer cells. The ability of these compounds to photocleave DNA is controlled by their incorporation into hybrid architectures with functional elements derived from natural amino acids. These conjugates are highly effective at inducing double-strand DNA cleavage and, in some cases, rival or even surpass both naturally occurring DNA cleavers and anticancer agents that are currently in clinical use. The possibility of triggering their activity in a photochemical and pH-sensitive fashion allows for a high degree of selectivity over activation. The conjugates were shown to penetrate cell membranes and induce efficient intracellular DNA cleavage. Initial in vitro tests against a variety of cancer cell lines confirm the potential of these compounds as anticancer agents at low nanomolar concentrations.
- Published
- 2012
35. Highly efficient molecular nickel catalysts for electrochemical hydrogen production from neutral water.
- Author
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Peili Zhang, Mei Wang, Yong Yang, Dehua Zheng, Kai Han, and Licheng Sun
- Subjects
NICKEL catalysts ,MOLECULAR structure ,ELECTROCHEMICAL analysis ,HYDROGEN production ,WATER - Abstract
A series of nickel complexes containing N
5 -pentadentate ligands with different amine-to-pyridine ratios were studied for electrochemical H2 production in neutral water and the one with a diamine-tripyridine ligand displays a TON of up to 308 000 over 60 h electrolysis at -1.25 V vs. SHE, with a Faradaic efficiency of ~91%. [ABSTRACT FROM AUTHOR]- Published
- 2014
- Full Text
- View/download PDF
36. Sub-wavelength surface structuring of NiTi alloy by femtosecond laser pulses.
- Author
-
Yang Yang, Jianjun Yang, Chunyong Liang, Hongshui Wang, Xiaonong Zhu, Dengfeng Kuang, and Yong Yang
- Subjects
NICKEL-titanium alloys ,FEMTOCHEMISTRY ,X-ray diffraction ,PHOTOELECTRON spectroscopy ,MOLECULAR structure - Abstract
Generation of self-organized sub-wavelength surface structures on a nickel–titanium alloy plate by femtosecond laser pulses is investigated experimentally through line-scribing experiments in air. It is found that Bragg-like relief gratings, with the orientation perpendicular to the laser polarization, are formed over the entire laser-scribed regions. The average period is measured as 630±30 nm. Distinctive features of these novel surface structures include nanoparticle-covered grating ridges and the maintainable spatial period regardless of incidence angles. With different laser parameters and sample scan speeds, sub-wavelength grating structures can evolve into cellular-like nanotextures. Optimal conditions for forming these surface structures are determined in terms of laser energy and scan speed. Elementary analyses of the structured surfaces by X-ray diffraction and photoelectron spectroscopy reveal that both the crystal structures and the chemical elements can remain in their original states, but the surface grains are refined and the atomic percentages are varied after femtosecond laser treatments. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
37. Pharmacophore Modelling and Virtual Screening for Identification of New Aurora-A Kinase Inhibitors.
- Author
-
Xiao-Qiang Deng, Hui-Yuan Wang, Ying-Lan Zhao, Ming-Li Xiang, Pei-Du Jiang, Zhi-Xing Cao, Yu-Zhu Zheng, Shi-Dong Luo, Luo-Ting Yu, Yu-Quan Wei, and Sheng-Yong Yang
- Subjects
CANCER treatment ,AURORAS ,MOLECULAR structure ,CANCER cells ,GENE expression ,DATABASE searching - Abstract
Aurora-A has been identified as one of the most attractive targets for cancer therapy and a considerable number of Aurora-A inhibitors have been reported recently. In order to clarify the essential structure–activity relationship for the known Aurora-A inhibitors as well as identify new lead compounds against Aurora-A, 3D pharmacophore models were developed based on the known inhibitors. The best hypothesis, Hypo1, was used to screen molecular structural databases, including Specs and China Natural Products Database for potential lead compounds. The hit compounds were subsequently subjected to filtering by Lipinski’s rules and docking study to refine the retrieved hits and as a result to reduce the rate of false positive. Finally, 39 compounds were purchased for further in vitro assay against several human tumour cell lines including A549, MCF-7, HepG2 and PC-3, in which Aurora-A is overexpressed. Two compounds show very low micromolar inhibition potency against some of these tumour cells. And they have been selected for further investigation. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
38. Scanning tunneling microscopy of the formation, transformation, and property of oligothiophene self-organizations on graphite and gold surfaces.
- Author
-
Zhi-Yong Yang, Hui-Min Zhang, Cun-Ji Yan, Shan-Shan Li, Hui-Juan Yan, Wei-Guo Song, and Li-Jun Wan
- Subjects
- *
SCANNING tunneling microscopy , *GRAPHITE , *GOLD , *MOLECULAR structure , *STRUCTURAL frame models - Abstract
Two alkyl-substituted dual oligothiophenes, quarterthiophene (4T)-trimethylene (tm)-octithiophene (8T) and 4T-tm-4T, were used to fabricate molecular structures on highly oriented pyrolytic graphite and Au(111) surfaces. The resulted structures were investigated by scanning tunneling microscopy. The 4T-tm-8T and 4T-tm-4T molecules self-organize into long-range ordered structures with linear and/or quasi-hexagonal patterns on highly oriented pyrolytic graphite at ambient temperature. Thermal annealing induced a phase transformation from quasi-hexagonal to linear in 4T-tm-8T adlayer. The molecules adsorbed on Au(111) surface in randomly folded and linear conformation. Based on scanning tunneling microscopy results, the structural models for different self-organizations were proposed. Scanning tunneling spectroscopy measurement showed the electronic property of individual molecules in the patterns. These results are significant in understanding the chemistry of molecular structure, including its formation, transformation, and electronic properties. They also help to fabricate oligothiophene assemblies with desired structures for future molecular devices. [ABSTRACT FROM AUTHOR]
- Published
- 2007
- Full Text
- View/download PDF
39. Indole Alkaloids from Kopsia hainanensis and Evaluation of Their Antimicrobial Activity.
- Author
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Yong Yang, Wen-Jian Zuo, You-Xing Zhao, Wen-Hua Dong, Wen-Li Mei, and Hao-Fu Dai
- Subjects
- *
CHROMATOGRAPHIC analysis , *MASS spectrometry methodology , *ALKALOIDS , *MOLECULAR structure , *NUCLEAR magnetic resonance spectroscopy , *PHARMACEUTICAL chemistry , *STAPHYLOCOCCUS aureus , *PLANT extracts , *DESCRIPTIVE statistics , *KANAMYCIN , *IN vitro studies - Abstract
Three new indole alkaloids, named kopsihainin D (1), kopsihainin E (2), and kopsihainin F (3), along with nine known compounds (4-12) were isolated from the twigs of Kopsia hainanensis. The structures of the new compounds were elucidated by spectroscopic methods including HRESIMS, UV, IR, and NMR. Compounds 1-3 and 5 showed inhibitory activity against Staphylococcus aureus with an antibacterial circle diameter of 11.2, 9.1, 10.3 and 9.7 mm, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
40. Structural evolution study of additions of Sb2S3 and CdS into GeS2 chalcogenide glass by Raman spectroscopy.
- Author
-
Hai-Tao Guo, Ming-Jie Zhang, Yan-Tao Xu, Xu-Sheng Xiao, and Zhi-Yong Yang
- Subjects
ANTIMONY sulfides ,CADMIUM sulfide ,GERMANIUM compounds ,ADDITION reactions ,CHALCOGENIDE glass ,MOLECULAR structure ,RAMAN spectroscopy - Abstract
The structures of pseudo-binary GeS
2 –Sb2 S3 , GeS2 –CdS, Sb2 S3 –CdS, and pseudo-ternary GeS2 –Sb2 S3 –CdS chalcogenide systems are systematically investigated by Raman spectroscopy. It is shown that a small number of [S3 Ge–GeS3 ] structural units (SUs) and -S-S-/S8 groups exist simultaneously in GeS2 glass which has a three-dimensional continuous network backbone consisting of cross-linked corner-sharing and edge-sharing [GeS4 ] tetrahedra. When Sb2 S3 is added into GeS2 glass, the network backbone becomes interconnected [GeS4 ] tetrahedra and [SbS3 ] pyramids. Moreover, Ge atoms in [S3 Ge–GeS3 ] SUs tend to capture S atoms from Sb2 S3 , leading to the formation of [S2 Sb–SbS2 ] SUs. When CdS is added into GeS2 glass, [Cd4 GeS6 ] polyhedra are formed, resulting in a strong crystallization tendency. In addition, Ge atoms in [S3 Ge–GeS3 ] SUs tend to capture S atoms from CdS, resulting in the dissolution of Ge–Ge bond. Co-melting of Sb2 S3 or CdS with GeS2 reduces the viscosity of the melt and improves the homogeneity of the glass. The GeS2 glass can only dissolve up to 10-mol% CdS without crystallization. In comparison, GeS2 –Sb2 S3 glasses can dissolve up to 20-mol% CdS, implying that Sb2 S3 could delay the construction of [Cd4 GeS6 ] polyhedron and increase the dissolving amount of CdS in the glass. [ABSTRACT FROM AUTHOR]- Published
- 2017
- Full Text
- View/download PDF
41. 5,17-Dibenzoyl-25,26,27,28-tetrahydroxycalix[4]arene.
- Author
-
Yong Yang, En-Chao Li, Feng-Xiang Chen, Cheng Peng, and Xian-Fa Shi
- Subjects
- *
CALIXARENES , *CRYSTALLOGRAPHY , *HYDROXYL group , *HYDROGEN bonding , *MOLECULAR structure , *CHEMICAL structure , *PHYSICAL & theoretical chemistry - Abstract
The structure of the title compound, C42H32O6, is an important example of the functionalization of the upper rim of calix[4]arene molecules. It possesses crystallographic twofold rotation symmetry and displays the calixarene cone conformation. The hydroxyl groups form intramolecular hydrogen bonds. [ABSTRACT FROM AUTHOR]
- Published
- 2006
- Full Text
- View/download PDF
42. Microwave Magnetic Properties and Natural Resonance of -Co Nanoparticles.
- Author
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Yong, Yang, Cai, Xu, Liang, Qiao, Xing, Li, and, Hua, and Fa, Li
- Subjects
- *
MAGNETIC crystals , *MICROWAVES , *COBALT , *NANOPARTICLES , *MOLECULAR structure , *MICROFABRICATION , *EPOXY resins , *PERMEABILITY , *DIFFERENTIAL equations - Abstract
Owing to the novel crystal structure, [?]-Co nanoparticles with an average diameter of 12nm are synthesized and the microwave magnetic properties of the epoxy resin composite with 50vol% [?]-Co particles are measured in the frequency range 0.1-7 GHz. The experimental resonance frequency (4.7 GHz) matches well with the values obtained by the theoretical calculation with the Kittel equation and fitting the experimental permeability dispersion curve via the Landau-Lifshitz equation. Hence the resonance peak is attributed to natural resonance mode. This work is believed to be beneficial for further understanding microwave applications of the novel [?]-Co nanoparticles. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
43. A structure-functionality insight into the bioactivity of microbial polysaccharides toward biomedical applications: A review.
- Author
-
Zhang, Hongxing, Li, Yan, Fu, Yinyi, Jiao, Haixin, Wang, Xiangyu, Wang, Qianqian, Zhou, Mengbo, Yong, Yang-chun, and Liu, Jun
- Subjects
- *
MICROBIAL polysaccharides , *MOLECULAR structure , *STRUCTURE-activity relationships , *FUNCTIONAL foods - Abstract
Microbial polysaccharides (MPs) are biopolymers secreted by microorganisms such as bacteria and fungi during their metabolic processes. Compared to polysaccharides derived from plants and animals, MPs have advantages such as wide sources, high production efficiency, and less susceptibility to natural environmental influences. The most attractive feature of MPs lies in their diverse biological activities, such as antioxidative, anti-tumor, antibacterial, and immunomodulatory activities, which have demonstrated immense potential for applications in functional foods, cosmetics, and biomedicine. These bioactivities are precisely regulated by their sophisticated molecular structure. However, the mechanisms underlying this precise regulation are not yet fully understood and continue to evolve. This article presents a comprehensive review of the most representative species of MPs, including their fermentation and purification processes and their biomedical applications in recent years. In particular, this work presents an in-depth analysis into the structure-activity relationships of MPs across multiple molecular levels. Additionally, this review discusses the challenges and prospects of investigating the structure-activity relationships, providing valuable insights into the broad and high-value utilization of MPs. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
44. A Helix−Turn−Helix Supersecondary Structure Based on Oligo(phenanthroline dicarboxamide)s.
- Author
-
Hai-Yu Hu, Jun-Feng Xiang, Yong Yang, and Chuan-Feng Chen
- Subjects
- *
MOLECULAR structure , *AMIDES , *X-ray crystallography , *STRUCTURAL bioinformatics - Abstract
An artificial helix−turn−helix (HTH) supersecondary structure based on the oligo(phenanthroline dicarboxamide)s, in which the 2,2‘-dimethoxy-1,1‘-binaphthyl-6,6‘-diamine subunit was utilized as the turn to impart a bias in the twist sense of the supersecondary structure, was reported. The HTH structure has been demonstrated by UV/vis, NMR, CD spectra, and X-ray crystal analysis. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
45. Determination of Rutin and Puerarin in Teas and Pharmaceutical Preparations Using Poly (Evans Blue) Film-Modified Electrodes.
- Author
-
Junxia Wang, Jingnan Mu, Jing Ma, Yong Yang, Maoqing Wang, Lei Zhu, and Xiaoyan Du
- Subjects
- *
TEA analysis , *CALIBRATION , *ELECTRODES , *HIGH performance liquid chromatography , *MOLECULAR structure , *RESEARCH funding , *ISOFLAVONES , *FLAVONOLS , *DESCRIPTIVE statistics ,RESEARCH evaluation - Abstract
Single-walled carbon nanotubes (SWCNTs)/poly (Evans blue)(poly-EB) film-modified glassy carbon (GC) electrodes were fabricated for the voltammetric determination of rutin and puerarin in teas and pharmaceutical preparations. The SWCNTs/poly-EB film-modified electrode showed excellent electrocatalytic activity towards the oxidation of rutin and puerarin. Two well-defined oxidation peaks of rutin and puerarin appeared at 510 and 810 mV, respectively. The peak current depended linearly on the concentration of rutin and puerarin in the range from 1.6 × 10-7 to 2.0 × 10-5 mol/L and 3.0 × 10-7 to 4.6 × 10-5 mol/L, respectively, with the detection limit of 8.2 × 10-8 mol/L for rutin and 1.2 × 10-7 mol/L for puerarin. The modified electrode was successfully applied to the determination of rutin and puerarin in teas and pharmaceutical preparations. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
- View/download PDF
46. Structural Basis for Broad and Potent Neutralization of HIV-1 by Antibody VRC01.
- Author
-
Tongqing Zhou, Georgiev, Ivelin, Xueling Wu, Zhi-Yong Yang, Kaifan Dai, Finzi, Andrés, Young Do Kwon, Scheid, Johannes F., Wei Shi, Ling Xu, Yongping Yang, Jiang Zhu, Nussenzweig, Michel C., Sodroski, Joseph, Shapiro, Lawrence, Nabel, Gary J., Mascola, John R., and Kwong, Peter D.
- Subjects
- *
GLYCOPROTEINS , *HIV antibodies , *AIDS vaccines , *MONOCLONAL antibodies , *IMMUNOGLOBULINS , *MOLECULAR genetics , *VIRAL receptors , *MOLECULAR structure - Abstract
During HIV-1 infection, antibodies are generated against the region of the viral gp120 envelope glycoprotein that binds CD4, the primary receptor for HIV-1. Among these antibodies, VRC01 achieves broad neutralization of diverse viral strains. We determined the crystal structure of VRC01 in complex with a human immunodeficiency virus HIV-1 gp120 core. VRC01 partially mimics CD4 interaction with gp120. A shift from the CD4-defined orientation, however, focuses VRC01 onto the vulnerable site of initial CD4 attachment, allowing it to overcome the glycan and conformational masking that diminishes the neutralization potency of most CD4-binding-site antibodies. To achieve this recognition, VRC01 contacts gp120 mainly through immunoglobulin V-gene regions substantially altered from their genomic precursors. Partial receptor mimicry and extensive affinity maturation thus facilitate neutralization of HIV-1 by natural human antibodies. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
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