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NQO1 Mediates Lenvatinib Resistance by Regulating ROS-induced Apoptosis in Hepatocellular Carcinoma

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Current Medical Science 2024年第1期44卷 168-179页

作者： Wei XUE Ting WANG Wen-jing TIAN Si-qi PANG hua-feng zhang Wei-dong JIA Department of General Surgery The First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefei 230027China Institute of Health and Medicine Hefei Comprehensive National Science CenterHefei 230601China The Chinese Academy of Sciences Key Laboratory of Innate Immunity and Chronic Disease School of Basic Medical SciencesDivision of Life Science and MedicineUniversity of Science and Technology of ChinaHefei 230027China

Objective Hepatocellular carcinoma(HCC)is the third leading cause of cancer-associated death *** a first-line drug for advanced HCC treatment,lenvatinib faces a significant hurdle due to the development of both intrinsic and acquired resistance among patients,and the underlying mechanism remains largely *** present study aims to identify the pivotal gene responsible for lenvatinib resistance in HCC,explore the potential molecular mechanism,and propose combinatorial therapeutic targets for HCC *** Cell viability and colony formation assays were conducted to evaluate the sensitivity of cells to lenvatinib and ***-Seq was used to determine the differences in transcriptome between parental cells and lenvatinib-resistant(LR)*** upregulated genes were analyzed by GO and KEGG ***,qPCR and Western blotting were employed to determine the relative gene expression ***,the intracellular reactive oxygen species(ROS)and apoptosis were detected by flow *** PLC-LR and Hep3B-LR were *** was a total of 116 significantly upregulated genes common to both LR cell *** GO and KEGG analyses indicated that these genes were involved in oxidoreductase and dehydrogenase activities,and reactive oxygen species ***,NAD(P)H:quinone oxidoreductase 1(NQO1)was highly expressed in LR cells,and was involved in the lenvatinib *** high expression of NQO1 decreased the production of ROS induced by lenvatinib,and subsequently suppressed the *** combination of lenvatinib and NQO1 inhibitor,dicoumarol,reversed the resistance of LR *** The high NQO1 expression in HCC cells impedes the lenvatinib-induced apoptosis by regulating the ROS levels,thereby promoting lenvatinib resistance in HCC cells.

关键词： hepatocellular carcinoma lenvatinib resistance NAD(P)H quinone oxidoreductase 1 reactive oxygen species apoptosis dicoumarol

Distributions of Neutron Exposures in AGB Stars and the Galaxy

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Chinese Journal of Astronomy and Astrophysics 2007年第2期7卷 224-234页

作者： Wen-Yuan Cui feng-hua zhang Wei-Juan zhang Lu zhang Bo zhang National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 Department of Physics Hebei Normal University Shijiazhuang 050016 Department of Modern Physics University of Science and Technology of China Hefei 230026 Graduate School of Chinese Academy of Sciences Bejing 100049

Based on the s-process nucleosynthesis model with the 13C（α, n）16O reaction occurring under radiative conditions in the interpulse phases, we investigate the characteristics of the distribution of neutron exposure in low-mass Asymptotic Giant Branch （AGB） stars. We introduce a new concept, the distribution of neutron exposures of the Galaxy （NEG）, to study the chemical evolution characteristics of the Galaxy for s-process elements. Using a chemical evolution model of the Galaxy, we develop a model for the NEG and obtain the evolution results of the NEG in different epochs. The present results appear to reasonably reproduce the distribution of neutron exposures of the solar system （hereafter NES）. The main component and the strong component in the NES are built up in different epochs. The strong component of the s-process is mainly synthesised in the low-mass and metal-poor AGB stars, and the main component is produced by the s-process in the low-mass AGB stars with higher metallicities.

关键词： Galaxy evolution- stars AGB and post-AGB- stars abundances

Efficient design of rotary traveling wave oscillator array via geometric programming

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第12期10卷 1815-1823页

作者： Li-jia CHEN hua-feng zhang Jin-fang ZHOU Kang-sheng CHEN Department o fin formation Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

This paper presents an efficient method for globally optimizing and automating component sizing for rotary traveling wave oscillator arrays. The lumped equivalent model of transmission lines loaded by inverter pairs is evaluated and posynomial functions for oscillation frequency, power dissipation, phase noise, etc. are formulated using transmission line theory. The re- sulting design problem can be posed as a geometric programJning problem, which can be efficiently solved with a convex opti- mization solver. The proposed method can compute the global optima more efficiently than the traditional iterative scheme and various design problems can be solved with the same circuit model. The globally optimal trade-off curves between competing objectives are also computed to carry out robust designs and quickly explore the design space.

关键词： Rotary traveling wave oscillator array (RTWOA) Clock distribution Transmission line resonator Global optimi-zation Geometric programming (GP)

Gastric and intestinal ectopic pancreas: Two case reports

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World Journal of Clinical Cases 2023年第29期11卷 7221-7226页

作者： huan zhang Hong-Yu Zhao feng-hua zhang Wei Liang Department of General Surgery Hebei General HospitalShijiazhuang 050051Hebei ProvinceChina

BACKGROUND Ectopic pancreas may be unfamiliar to many people because it is rare and difficult to ***,this disease is highly susceptible to misdiagnosis and missed *** this article,we report two cases of pancreatic heterotopia in the gastric sinus and small intestine,respectively,both of which were confirmed by histopathological *** SUMMARY The first patient was a 43-year-old female which reported abdominal distension for 2 *** second was a 67-year-old female who experienced intermittent epigastric discomfort for 15 *** both cases,there was no confirmed preoperative examination,and the postoperative pathology indicated the presence of ectopic *** The diagnosis of ectopic pancreas is difficult,and is often prone to misdiagnosis and the possibility of being *** laboratory tests and imaging tests should be carefully evaluated before surgery to achieve early detection,early diagnosis and early treatment.

关键词： Gastric Intestinal Ectopic pancreas Case report

Can pigment gallstones be induced by biliary stricture and prevented by medicine in Guinea pigs?

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World Journal of Gastroenterology 2007年第19期13卷 2703-2706页

作者： Zhi Xu Xiao-feng Ling Wan-hua zhang Xiao-Si Zhou Department of Surgery Third Hospital of Peking UniversityBeijing 100083 China

AIM: To determine the relationship between biliary stricture and pigment gallstone formation, and the prevention of pigment gallstones with medicine. METHODS: One hundred and eighteen male guinea pigs were randomly divided into four groups: stricture group (S, n = 30) underwent partial ligation of common bile duct, and fed on regular chow; S plus medicine group (S+M, n = 27) underwent the same operation but fed on medicinal chow (0.3 g chenodeoxycholic acid, 0.5 g glucurolactone, and 0.5 g aspirin were mixed up in 1.2 kg regular chow); medicinal control group (C+M, n = 30) was free of operation, and fed on medicinal chow; and control group (C, n = 31) was free of operation and fed on regular chow. One week later, laparotomy was performed, and the bile of gallbladder was collected, measured, and cultured. RESULTS: Gallstones were identif ied. Pigment gallstones were induced by biliary stricture in 95% (22/23) of S group. In the S+M group, the incidence of gallstone was reduced to 55% (11/20, vs S group, P < 0.01). The changes of indirect bilirubin and ionized calcium in the bile were consistent with gallstone incidences. CONCLUSION: Biliary stricture can cause pigment gallstone formation in guinea pigs, and the medicines used can lower the incidence of gallstones. The bilirubin and ionized calcium play important roles in pigment gallstone formation.

关键词： Biliary stricture Pigment gallstone formation Prophylaxis Animal model

An Efficient Ruthenium Catalyst Bearing Tetradentate Ligand forHydrogenations of Carbon Dioxide

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Chinese Journal of Chemistry 2018年第11期36卷 1000-1002页

作者： feng-hua zhang Chong Liu Wei Li Gui-Long Tian Jian-hua Xie Qi-Lin Zhou State Key Laboratory and Institute of Elemento-organic Chemistry Col-lege of Chemistry Nankai University Tianjin 300071 China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300071 China

A ruthenium complex with a tetradentate bipyridine ligand was proved to be a highly efficient catalyst for the conversions of CO 2 . Turnover numbers up to 300 000, 9800, and 2100 were achieved for the hydrogenations of CO 2 to formamides, formamides to methanol and amines, and the direct hydrogenation of CO 2 to methanol, respectively.

关键词： carbon dioxide methanol formamide ruthenium hydrogenation reduction

Identification and Evolution of Groundwater Chemistry in the Ejin Sub-Basin of the Heihe River, Northwest China

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Pedosphere 2007年第3期17卷 331-342页

作者： SU Yong-Hong feng Qi ZHU Gao-feng SI Jian-hua zhang Yan-Wu Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou730000 （China） School of Mathematics and Statistics Lanzhou University Lanzhou 730000 （China）

Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous Region, China, to understand the groundwater evolution, to identify the predominant geochemical processes taking place along the horizontal groundwater flow path, and to characterize anthropogenic factors affecting the groundwater environment based on previous data. The concentrations of major ions and total dissolved solids （TDS） in the groundwater showed a great variation, with 62.5% of the samples being brackish （TDS ≥ 1 000 mg L^-l）. The groundwater system showed a gradual hydro-chemical zonation composed of Na^＋ -HCO3^-, Na^＋ -Mg^2＋ -SO4 ^2 -Cl^-, and Na^＋ -Cl^-. The relationships among the dissolved species allowed identification of the origin of solutes and the processes that generated the observed water compositions. The dissolution of halite, dolomite, and 2- gypsum explained, in part, the presence of Na^＋, K^＋, Cl^-, SO^4 , and Ca^2＋, but other processes, such as mixing, Na^＋ exchange for Ca^2＋ and Mg^2＋, and calcite precipitation also contributed to the composition of water. Human activity, in particular large-scale water resources development associated with dramatic population growth in the last 50 years, has led to tremendous changes in the groundwater regime, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Solving these largely anthropogenic problems requires concerted, massive and long-term efforts.

关键词： Ejin Sub-Basin groundwater quality Heihe River human impact water resources development

Influence of Trace Amount of Calponin on Smooth Muscle Myosin in Different States

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 529-536页

作者： Jing-Xian YANG, Xiao-hua feng, Ying zhang, and Yuan LIN Department of Pharmacology, Dalian Medical University, Dalian 116027, China Department of Pharmacology Dalian Medical UniversityDalian 116027 China

Calponin (CaP), a thin filament-associated protein, is thought to be involved in modulating smooth muscle contractile activity, but the role and mechanism keep unknown. In this study, trace amount of calponin (TAC) was found to obviously influence myosin in different states in Ca2+-independent manner, suggesting a high efficient interaction between TAC and myosin. In this assay, the lowest ratio of CaP vs. myosin was 1:10,000, with the concentration of CaP 10,000-fold lower than that used previously. Myosin phosphorylation, myosin Mg2+-ATPase activity and protein binding activity were detected to determine the effects of TAC on the myosin in different states. The amount of precipitated myosin that bound to TAC was used as the index to determine the interaction between myosin and TAC in binding assay. Our data showed that in the absence of actin, TAC significantly increased the precipitation of unphosphorylated myosin, Ca2+- dependently or independently phosphorylated myosin by MLCK, and stimulated the Mg2+-ATPase activities of these myosins slightly but significantly. However, no obvious change of precipitation of myosin phospho- rylated by PKA was observed, indicating the relatively selective effect of TAC. In the presence of actin, the increase of myosin precipitations was abolished, and no obvious change of actin precipitations and actin- activated myosin Mg2+-ATPase activities were observed implicating the high efficiency of TAC on myosin being present in the absence of actin. Although we can not give conclusive comments to our results, we propose that the high efficiency of TAC-myosin interaction is present when actin is dissociated from myosin, even if CaP/myosin ratio is very low; this high efficient interaction can be abolished by actin. However, why and how TAC can possess such a high efficiency to influence myosin and how the physiological significance of the high efficiency of TAC is in regulating the interaction between myosin and actin remain to be inve

关键词： trace amount of calponin protein binding phosphorylation myosin Mg2+-ATPase

Mechanism of local solidification time variations with melt rate during vacuum arc remelting process of 8Cr4Mo4V high-strength steel

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Journal of Iron and Steel Research International 2024年第2期31卷 377-388页

作者： Tao Pan Hong-chun Zhu Zhou-hua Jiang hua-bing Li Rui zhang Hao feng School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819LiaoningChina

A 2D axisymmetric numerical model was established to investigate the variations of molten pool with different melt rates during the vacuum arc remelting of 8Cr4Mo4V high-strength steel,and the ingot growth was simulated by dynamic mesh *** results show that as the ingot grows,the molten pool profile changes from shallow and flat to V-shaped,and both the molten pool depth and the mushy width ***,the variation of both the molten pool shape and the mushy width melt rate is clarified by the thermal equilibrium *** melt rate increases,both the molten pool depth and the mushy width *** is caused by the increment in sensible heat stored in the ingot due to the limitation of the cooling capacity of the *** nonlinear increment in sensible heat leads to a nonlinear increase in the mushy *** addition,as melt rate increases,the local solidification time(LST)of ingot decreases obviously at first and then *** melt rate is controlled in a suitable range,LST is the lowest and the secondary dendrite arm spacing of the ingot is the smallest,which can effectively improve the compactness degree of 8Cr4Mo4V high-strength steel.

关键词： 8Cr4Mo4V high-strength steel Vacuum arc remelting process Melt rate Molten pool Local solidification time