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161.
Synthetic and Biological Studies of Sesquiterpene Polygodial: Activity of 9‐Epipolygodial against Drug‐Resistant Cancer Cells
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Dr. Ramesh Dasari Annelise De Carvalho Derek C. Medellin Kelsey N. Middleton Dr. Frédéric Hague Marie N. M. Volmar Prof. Liliya V. Frolova Dr. Mateus F. Rossato Jorge J. De La Chapa Nicholas F. Dybdal‐Hargreaves Akshita Pillai Prof. Véronique Mathieu Prof. Snezna Rogelj Prof. Cara B. Gonzales Prof. João B. Calixto Prof. Antonio Evidente Dr. Mathieu Gautier Dr. Gnanasekar Munirathinam Prof. Rainer Glass Prof. Patricia Burth Dr. Stephen C. Pelly Prof. Willem A. L. van Otterlo Prof. Robert Kiss Prof. Alexander Kornienko 《ChemMedChem》2015,10(12):2014-2026
Polygodial, a terpenoid dialdehyde isolated from Polygonum hydropiper L., is a known agonist of the transient receptor potential vanilloid 1 (TRPV1). In this investigation a series of polygodial analogues were prepared and investigated for TRPV1‐agonist and anticancer activities. These experiments led to the identification of 9‐epipolygodial, which has antiproliferative potency significantly exceeding that of polygodial. 9‐Epipolygodial was found to maintain potency against apoptosis‐resistant cancer cells as well as those displaying the multidrug‐resistant (MDR) phenotype. In addition, the chemical feasibility for the previously proposed mechanism of action of polygodial, involving the formation of a Paal–Knorr pyrrole with a lysine residue on the target protein, was demonstrated by the synthesis of a stable polygodial pyrrole derivative. These studies reveal rich chemical and biological properties associated with polygodial and its direct derivatives. These compounds should inspire further work in this area aimed at the development of new pharmacological agents, or the exploration of novel mechanisms of covalent modification of biological molecules with natural products. 相似文献
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165.
NOC路由节点VLSI设计 总被引:2,自引:2,他引:0
基于wormhole交换策略和目的地址确定性路由算法,采用三级流水线的结构实现了片上网络中的路由节点.该路由节点适用于Mesh和Torus拓扑,并采用虚通道技术增加吞吐量.在Xilinx的FPGA上实现后可知,该路由节点最高可工作在130MHz的时钟频率上,传输带宽为20.8Gb/s. 相似文献
166.
《Journal of the European Ceramic Society》2023,43(8):3034-3042
Pitch-based short carbon fibres reinforced Csf/ZrB2-SiC composites were fabricated by direct ink writing of short carbon fibres, followed by slurry impregnation and reactive melt infiltration. Ablation behaviour of the Csf/ZrB2-SiC composite was studied by air plasma test. It is indicated that the skeleton of the oriented short carbon fibres provides heat diffusion channels. Consequently, temperatures at the ablation surface are as low as ∼1730 oC and ∼2000 oC respectively at 4 MW/m2 and 5 MW/m2. The composite presents outstanding ablation-resistant performance with a linear recession rate of ∼ − 0.04 µm/s and mass recession rate of ∼ − 3.40 mg/s at 4 MW/m2, ∼ − 0.17 µm/s and ∼ 3.58 mg/s at 5 MW/m2. It is revealed that the fibres area and matrix area of the composite present different ablation mechanisms. The fibres area is ablated severely, while the matrix area presents excellent ablation-resistance with continuous ZrO2-SiO2 protective layer. 相似文献
167.
《Journal of the European Ceramic Society》2023,43(3):1117-1126
A novel method of producing complex ceramic and metallic parts with designed internal channels is developed. The method utilizes a combination of the additive manufacturing technique of solvent jetting and spark plasma sintering (SPS.) The developed manufacturing approach brings benefits in producing complex shapes with internal channels. Along with geometric customization of the 3D printed mold, a major advantage of this method is the removal of the need for a long debinding process, usually necessary with other 3D printing methods, by using the SPS. High density ceramic and metallic complex parts with internal channels were successfully produced with close to theoretical densities. The conducted studies include the development of a model that can predict the evolution and/or distortions of the complex-shaped powder assembly during the sintering process. The model is based on the continuum theory of sintering formulations embedded in a finite element code. 相似文献
168.
针对纸张定量在线检测信号受“温漂”噪声影响稳定性差、补偿效果不理想的问题,从定量检测原理出发对噪声干扰源及主要耦合通道进行了时-频域分析和研究,并根据定量信号和噪声不同的频谱分布规律,构造了相应的巴特沃思滤波器处理定量信号。 相似文献
169.
Dr. Shixin Ye Morgane Riou Stéphanie Carvalho Dr. Pierre Paoletti 《Chembiochem : a European journal of chemical biology》2013,14(2):230-235
Heterologous expression of ligand‐gated ion channels (LGICs) in Xenopus laevis oocytes combined with site‐directed mutagenesis has been demonstrated to be a powerful approach to study structure–function relationships. In particular, introducing unnatural amino acids (UAAs) has enabled modifications that are not found in natural proteins. However, the current strategy relies on the technically demanding in vitro synthesis of aminoacylated suppressor tRNA. We report here a general method that circumvents this limitation by utilizing orthogonal aminoacyl‐tRNA synthetase (aaRS)/suppressor tRNACUA pairs to genetically encode UAAs in Xenopus oocytes. We show that UAAs inserted in the N‐terminal domain of N‐methyl‐D ‐aspartate receptors (NMDARs) serve as photo‐crosslinkers that lock the receptor in a discrete conformational state in response to UV photo treatment. Our method should be generally applicable to studies of other LGICs in Xenopus oocytes. 相似文献
170.
Optogenetics Comes of Age: Novel Inhibitory Light‐Gated Anionic Channels Allow Efficient Silencing of Neural Function
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Dr. Alex Peralvárez‐Marín Prof. Pere Garriga 《Chembiochem : a European journal of chemical biology》2016,17(3):204-206
Optogenetics, the developing field of research that uses light‐switchable biochemical tools in a sophisticated technological approach to monitor or control neural function, is rapidly evolving with the discovery and development of novel microbial rhodopsins. Light‐absorbing membrane proteins, as tools for brain research, are promoting new applications within the discipline of optogenetics. Light‐gated rhodopsin ion channels with better intrinsic light sensitivity and improved resolution are needed to overcome some of the current limitations of existing molecules. The recent discovery of light‐gated inhibitory anion channels opens new opportunities for studying physiological neural processes and, at the same time, represent a powerful approach for elucidating the mechanisms of neurological and mental disorders that could benefit from this approach. 相似文献