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Cucurbitacin B suppresses metastasis mediated by reactive oxygen species(ROS) via focal adhesion kinase(FAK) in breast cancer MDA-MB-231 cells

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Chinese Journal of Natural Medicines 2018年第1期16卷 10-19页

作者： luo wei-wei ZHAO Wen-Wen LU Jin-Jian WANG Yi-Tao CHEN Xiu-Ping State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical Science University of Macao

Metastasis is responsible for the majority of cancer-related deaths and prevention of metastasis remains a big challenge for cancer therapy. Cucurbitacin B(Cuc B) is a natural triterpenoid with potent anticancer activities while its effect on metastasis remains unclear. In the present study, the inhibitory effect and mechanisms of Cuc B on metastasis were investigated in MDA-MB-231 breast cancer cells. The cells were treated with or without Cuc B, and the cytotoxicity was determined by MTT assay. The effect of Cuc B on metastasis was evaluated with wound healing, transwell, and adhesion assays. Furthermore, the adhesion of cancer cells to endothelial cells was determined. The protein expression was determined by Western blotting. Cuc B(< 100 nmol·L~^(-1)) showed no obvious cytotoxicity to MDA-MB-231 cells, but significantly inhibited migration, invasion, and adhesion to Matrigel, fibronectin, type I collagen, and endothelial cells. Cuc B dramatically inhibited the phosphorylation of focal adhesion kinase(FAK) and paxillin in dose-and time-dependent manners. Furthermore, Cuc B induced intracellular reactive oxygen species(ROS) generation, which could be reduced by N-acetyl-l-cysteine(NAC). In addition, NAC pretreatment could reverse Cuc B-induced suppression of migration and adhesion, expression of FAK, but showed no effect on paxillin expression. In summary, Cuc B suppressed ROS-dependent metastasis through FAK pathway in breast cancer MDA-MB-231 cells, demonstrating novel mechanisms for the anticancer effects of Cuc B.

关键词： Cucurbitacin B Metastasis ROS FAK Breast Cancer

Changes of Cu, Zn, and Cd speciation in sewage sludge during composting

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Journal of Environmental Sciences 2005年第6期17卷 957-961页

作者： GAO Ding ZHENG Guo-di CHEN Tong-bin luo wei GAO wei ZHANG Yi-an LI Yan-xia Center for Environmental Remediation Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

The potential toxicity risks from heavy metals depend on their chemical speciation. The four stages of the Tessier sequential extraction method were employed to investigate changes in heavy metal speciation （Cu, Zn, and Cd） of sewage sludge during forced aeration composting, and then to identify whether the composting process would reduce or enhance their toxicities. Throughout the composting process, the exchangeable, carbonate-bound, Fe-Mn oxide-bound, and organic matter-bound fractions of Cu were converted to the residual Cu fraction. The organic matter-bound Cu fraction greatly contributed to this transformation. Residual Zn fraction was transformed to the Fe-Mn oxide-bound and organic matter-bound fractions after composting. The residual Zn fraction was a major contributor to the organic matter-bound Zn fraction. The availability of Cu and Zn was reduced by composting such that the risk of heavy metal toxicity decreased with prolonged treatment times. Additionally, attention should be paid to the increased availability of Cd in sewage sludge after composting treatment.

关键词： composting distribution heavy metal sewage sludge speciation

Boosting Oxygen Evolution Reaction Performance on NiFe‑Based Catalysts Through d‑Orbital Hybridization

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Nano-Micro Letters 2025年第1期17卷 281-292页

作者： Xing Wang wei Pi Sheng Hu Haifeng Bao Na Yao wei luo State Key Laboratory of New Textile Materials and Advanced Processing Technology Key Laboratory of New Textile Materials and Applications of Hubei ProvinceSchool of Materials Science and EngineeringWuhan Textile UniversityWuhan 430200People’s Republic of China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072People’s Republic of China

Anion-exchange membrane water electrolyzers(AEMWEs)for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based *** introducing a third metal into NiFe-based catalysts to construct asymmetrical M-NiFe units,the d-orbital and electronic structures can be adjusted,which is an important strategy to achieve sufficient oxygen evolution reaction(OER)performance in ***,the ternary NiFeM(M:La,Mo)catalysts featured with distinct M-NiFe units and varying d-orbitals are reported in this *** and theoretical calculation results reveal that the doping of La leads to optimized hybridization between d orbital in NiFeM and 2p in oxygen,resulting in enhanced adsorption strength of oxygen intermediates,and reduced rate-determining step energy barrier,which is responsible for the enhanced OER *** critically,the obtained NiFeLa catalyst only requires 1.58 V to reach 1 A cm^(−2) in an anion exchange membrane electrolyzer and demonstrates excellent long-term stability of up to 600 h.

关键词： NiFe-based catalysts d-orbital coupling Oxygen evolution reaction Anion exchange membrane electrolyzer

A functional cathode sodium compensation agent for stable sodium-ion batteries

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Green Energy & Environment 2025年第1期10卷 173-182页

作者： wei Wu Zhenglin Hu Zhengfei Zhao Aoxuan Wang Jiayan luo Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin300072China State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Jiao Tong University Shaoxing Research Institute of Renewable Energy and Molecular Engineering Shaoxing312000China

Hard carbon(HC)is widely used in sodium-ion batteries(SIBs),but its performance has always been limited by lowinitial Coulombic efficiency(ICE)and cycling *** compensation agent is a favorable strategy to make up for the loss of active sodium ions consumed *** it lacks agent that effectively decomposes to increase the active sodium ions as well as regulate carbon defects for decreasing the irreversible sodium ions ***,we propose 1,2-dihydroxybenzene Na salt(NaDB)as a cathode compensation agent with high specific capacity(347.9 mAh g^(-1)),lower desodiation potential(2.4–2.8 V)and high utilization(99%).Meanwhile,its byproduct could functionalize HC with more C]O groups and promote its reversible ***,the presodiation hard carbon(pHC)anode exhibits highly reversible capacity of 204.7 mAh g^(-1) with 98%retention at 5 C rate over 1000 ***,with 5 wt%NaDB initially coated on the Na3V2(PO4)3(NVP)cathode,the capacity retention of NVP t NaDBjHC cell could increase from 22%to 89%after 1000 cycles at 1 C *** work provides a new avenue to improve reversible capacity and cycling performance of SIBs through designing functional cathode compensation agent.

关键词： Hard carbon ICE Cathode compensation agent Reversible capacity Stability

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动叶具有缩放型流道的涡轮级效率特性分析

工程热物理学报 2014年第11期35卷 2168-2172页

作者：徐晓赵巍雒伟伟中国科学院工程热物理研究所北京100190 中国科学院大学北京100190 中国科学院轻型动力重点实验室北京100190

针对一动叶采用缩放式叶型设计、以无导叶对转涡轮为应用背景的涡轮级,通过数值模拟进行研究发现,在设计换算转速下,该涡轮级效率特性呈现"双峰僧'的特点。随着落压比增大,首先动叶进气攻角由负变为零,效率升高并达到极大值;其后,动叶... 详细信息

针对一动叶采用缩放式叶型设计、以无导叶对转涡轮为应用背景的涡轮级,通过数值模拟进行研究发现,在设计换算转速下,该涡轮级效率特性呈现"双峰僧'的特点。随着落压比增大,首先动叶进气攻角由负变为零,效率升高并达到极大值;其后,动叶流道内形成正激波,其自身产生波阻并在吸力面引起边界层分离,效率下降;随后,该激波向下游移至叶片尾缘,尾迹损失明显增加,加上波阻、边界层分离的综合作用,效率达到极小值;然后,该激波演变为尾缘斜激波,自身波阻减小,而且它在吸力面引起的边界层分离消失,流道内总体损失下降,效率又会上升并在设计点附近达到极大值;其后,该激波波前马赫数不断增大,波阻损失随之增加,同时尾迹损失也持续增加,效率又会下降。结果显示,高负荷跨音工况下激波与边界层干扰引起的边界层分离损失以及动叶高出口马赫数时尾缘区域的损失(包括波阻损失和尾迹损失)占总体损失的至少1/2以上,在设计优化过程中应重点关注与之相关的动叶吸力面扩张段和叶片尾缘区域。

关键词：缩放型叶栅流道无导叶对转涡轮效率特性数值模拟

Design and Application of Turbine Cascade Partitioned Endwall Profiling

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Journal of Thermal Science 2025年第1期34卷 110-128页

作者： ZENG Fei JIANG Ruiqi XUE Xingxu DU wei luo Lei ZHOU Xun AECC Hunan Aviation Powerplant Research Institute School of Energy Science and Technology Harbin Institute of Technology Science and Technology on Diesel Engine Turbocharging Laboratory China North Engine Research Institute

The influence of partitioned profiling design based on a large-pitch highly loaded cascade is studied by numerical *** partitioned profile is mainly composed of a pressure-side convex structure near the leading edge and a suction-side convex structure at the midstream and downstream sides of the *** influence of the change in the vertex axial position and peak value of the B-line on the secondary flow control is *** this paper,air(ideal gas) is selected as the flow *** average static pressure at the outlet and the average total temperature at the inlet are kept *** γ-θ is used as the turbulence *** results show that the pressure-side convex structure suppresses the spanwise and pitchwise migration of the inlet flow by adjusting the static pressure distribution of the flow field,so the development of the pressure-side leg of the horseshoe vortex is effectively *** suction-side convex structure adjusts the static pressure distribution of the flow field and increases the included angle between the cross-flow and suction surface,so the accumulation of low-momentum fluid,the development of a corner vortex and the flow separation at the trailing edge of the suction-side surface are all suppressed near the endwall-suction ***,the energy loss coefficient of the large-pitch highly loaded cascade is decreased from 0.0564 to 0.0485,representing a 25% reduction in secondary flow losses.

关键词： Vortex flow

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei luo Qiu-Quan Pan Qi-wei Yao Xing-Zhong Shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

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1+1对转涡轮变工况性能分析与优化设计

推进技术 2017年第7期38卷 1483-1490页

作者：常骐越赵巍雒伟伟唐菲中国科学院工程热物理研究所北京100190 中国科学院大学北京100190 中国科学院轻型动力重点实验室北京100190

为阐明1+1对转涡轮变工况性能损失的主要来源并提出改进方法,以1+1对转涡轮为例进行了部分载荷工况下的流场模拟、分析和优化。与相同设计参数的同转涡轮进行部分载荷工况流场对比,发现部分转速下同转涡轮在级间导叶吸力面前缘出现分离,... 详细信息

为阐明1+1对转涡轮变工况性能损失的主要来源并提出改进方法,以1+1对转涡轮为例进行了部分载荷工况下的流场模拟、分析和优化。与相同设计参数的同转涡轮进行部分载荷工况流场对比,发现部分转速下同转涡轮在级间导叶吸力面前缘出现分离,而1+1对转涡轮在压力面前缘出现分离。针对此流动损失,为1+1对转涡轮级间导叶提出了一种基于分离角的压力面优化设计方法,提高了近前缘压力面的气流速度,增强了其对负攻角的适应性,基本消除了叶片14%、58%和92%叶高处压力面前缘的流动分离,在正攻角工况下亦保持了良好气动性能。数值验证了该涡轮的效率在全工况范围内明显提高,而设计点效率未受负面影响。其中,在对转涡轮70%和50%设计转速的两个工况点上,低压涡轮效率较优化前分别提升了1.5%和2.0%,涡轮总效率较优化前分别提升了0.5%和0.7%。

关键词： 1+1对转涡轮变工况优化设计

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随机需求和产量下基于损失规避的零售商博弈

控制与决策 2017年第5期32卷 920-924页

作者：刘伟宋士吉乔颖罗伟伟军事经济学院基础部武汉430035 清华大学自动化系北京100084 湖北经济学院工商管理学院武汉430205

研究在需求和产量均为随机变量的情况下,带有损失规避偏好的零售商之间的博弈.当多个相同的零售商向同一供应商订购时,如果总需求按照每个零售商的订购量在总订购量中所占比例进行分配,则该博弈中存在唯一的对称性Nash均衡,且总均衡订... 详细信息

研究在需求和产量均为随机变量的情况下,带有损失规避偏好的零售商之间的博弈.当多个相同的零售商向同一供应商订购时,如果总需求按照每个零售商的订购量在总订购量中所占比例进行分配,则该博弈中存在唯一的对称性Nash均衡,且总均衡订购量关于损失规避水平递减,关于零售商数量递增.此外,如果损失规避水平(零售商数量)高于(低于)临界值,则竞争情况下供应链总库存水平比集中管理情况下的低.仿真实验验证了上述结果.

关键词：损失规避随机产量博弈库存