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Icariin protects vascular endothelial cells from oxidative stress through inhibiting endoplasmic reticulum stress

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Journal of Integrative Medicine 2019年第3期17卷 205-212页

作者： Fang-yuan Wang jian jia Huan-huan Song Cheng-ming jia Chang-bo Chen jing Ma Department of Traditional Chinese Medicine Army Medical Center in Traditional Chinese MedicineXijing HospitalForth Military Medical University

Objective: To investigate the protective effect and underlying mechanism(s) of icariin(ICA) in preventing hydrogen peroxide(H_2O_2)-induced vascular endothelial cell injury via endoplasmic reticulum stress(ERS).Methods: To study the effects of ICA on H_2O_2-induced damage, we used the cell counting kit-8 assay to detect cell viability and the terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay to determine cell adhesion and apoptosis, respectively. Spectrophotometry and enzyme-linked immunosorbent assay were used to measure the expression levels of superoxide dismutase(SOD) and glutathione peroxidase(GSH-Px). Subsequently, glucose-regulated protein 78(GRP78), activating transcription factor-4(ATF4) and eukaryotic initiation factor-2 a(eIF2 a) were detected using Western ***: In human umbilical vein endothelial cells, different concentrations of ICA exhibited multiple effects, including reduced H_2O_2 damage, improved cell viability and adhesion, reduced cell apoptosis and increased SOD and GSH-Px activity. Among the ICA concentrations used, only the H_2O_2+ 100 lmol/L ICA group had significant differences compared to the H_2O_2 group. ERS activators H_2O_2 and DL-dithiothreitol(DTT) significantly increased GRP78, ATF4 and eIF2 a expressions, decreased cell activity and reduced SOD and GSH-Px activity. In contrast, the H_2O_2+ 100 lmol/L ICA and H_2O_2+ 100 lmol/L ICA + DTT groups had significant inhibitory effects on the expressions of GRP78,ATF4 and eIF2 a proteins, showing enhanced cell viability and SOD and GSH-Px ***: The results showed the dose-dependent effects of ICA against H_2O_2-induced injury in vascular endothelial cells. The inhibition of GRP78, ATF4 and eIF2 a protein expressions in the ERS, and the subsequent alleviation of oxidative stress damage, might be the molecular mechanism.

关键词： Icariin Endoplasmic reticulum stress Human umbilical vein endothelial cells Oxidative stress

Research of Optical Fiber Coil Winding Model Based on Large-deformation Theory of Elasticity and Its Application

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Chinese Journal of Aeronautics 2011年第5期24卷 640-647页

作者： jia ming YANG Gongliu School of Instrumentation Science and Opto-electronics Engineering Beihang University Beijing 100191 China

Optical fiber coil winding model is used to guide proper and high precision coil winding for fiber optic gyroscope （FOG） application. Based on the large-deformation theory of elasticity, stress analysis of optical fiber free end has been made and balance equation of infinitesimal fiber is deduced, then deformation equation is derived by substituting terminal conditions. On condition that only axial tensile force exists, approximate curve equation has been built in small angle deformation scope. The comparison of tangent point longitudinal coordinate result between theory and approximation gives constant of integration, and expression with tangent point as origin of coordinate is readjusted. Analyzing the winding parameters of an example, it is clear that the horizontal distance from the highest point of wheel to fiber tangent point has millimeter order of magnitude and significant difference with fiber tension variation, and maintains invariant when wheel radius changes. The height of tension and accurate position of tangent point are defined for proper fiber guide. For application to fiber optic gyroscope, spiral-disc winding method and nonideal deformation of straddle section are analyzed, and then spiral-disc quadrupole pattern winding method has been introduced and realized by winding system. The winding results approve that the winding model is applicable.

关键词： fibers fiber optics large-deformation fiber optic gyroscope spiral-disc winding quadrupole pattern

Tool Wear and Its Effect on Surface Roughness in Diamond Cutting of Glass Soda-lime

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1224-1230页

作者： jia Peng ZHOU ming Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China School of Mechanical and Electrical Engineering Harbin Institute of Technology Harbin 150001 China

For the technology of diamond cutting of optical glass, the high tool wear rate is a main reason for hindering the practical application of this technology. Many researches on diamond tool wear in glass cutting rest on wear phenomenon describing simply without analyzing the genesis of wear phenomenon and interpreting the formation process of tool wear in mechanics. For in depth understanding of the tool wear and its effect on surface roughness in diamond cutting of glass, experiments of diamond turning with cutting distance increasing gradually are carried out on soda-lime glass. The wear morphology of rake face and flank face, the corresponding surface features of workpiece and the surface roughness, and the material compositions of flank wear area are detected. Experimental results indicate that the flank wear is predominant in diamond cutting glass and the flank wear land is characterized by micro-grooves, some smooth crater on the rake face is also seen. The surface roughness begins to increase rapidly, when the cutting mode changes from ductile to brittle for the aggravation of tool wear with the cutting distance over 150 m. The main mechanisms of inducing tool wear in diamond cutting of glass are diffusion, mechanical friction, thermo-chemical action and abrasive wear. The proposed research makes analysis and research from wear mechanism on the tool wear and its effect on surface roughness in diamond cutting of glass, and provides theoretical basis for minimizing the tool wear in diamond cutting brittle materials, such as optical glass.

关键词： diamond cutting tool wear surface roughness soda-lime glass

Insights into the thermochemical evolution of maleic anhydride-initiated esterified starch to construct hard carbon microspheres for lithium-ion batteries

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Journal of Energy Chemistry 2022年第3期31卷 448-458,I0012页

作者： ming-Xin Song Li-jing Xie jia-Yao Cheng Zong-Lin Yi Ge Song Xiao-Yang jia jing-Peng Chen Quan-Gui Guo Cheng-Meng Chen CAS Key Laboratory of Carbon Materials Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina University of Chinese Academy of Sciences Beijing 100049China College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

Starch,as a typical polysaccharide with natural spherical morphology,is not only a preferred precursor for preparing carbon materials but also a model polymer for investigating thermochemical evolution ***,starch usually suffers from severe foaming and low carbon yield during direct ***,we report a simple and eco-friendly dry strategy,by maleic anhydride initiating the esterification of starch,to design carbon microspheres against the starch ***,the infuence of ester grafting on the pyrolytic behavior of starch is also *** formation of ester groups in precursor guarantees the structural stability of starch-based intermediate because it can promote the accumulation of unsaturated species and accelerate the water elimination during ***,the esterification and dehydration reactions greatly deplete the primary hydroxyl groups in the starch molecules and thus the rapid levoglucosan release is inhibited,which well keeps the spherical morphology of starch and ensures the high carbon *** further exploration as anode materials for Lithium-ion batteries,the obtained carbon microspheres exhibit good cyclability and rate performance with a reversible capacity of 444 m Ah g^(-1)at 50 m A g^(-1).This work provides theoretical fundamentals for the controllable thermal transformation of biomass towards wide applications.

关键词： Maleic anhydride esterified starch Dry strategy Thermochemical evolution Hard carbon microspheres Lithium-ion batteries

New multi-color photometric investigations of solar-like contact binary V680 Per

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Research in Astronomy and Astrophysics 2020年第4期20卷 49-56页

作者： jing-jing Wang jia-jia He Song-Qing Zhao China University of Petroleum–Beijing at Karamay Karamay 834000China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China

High-precision CCD photometric observations of the contact binary V680 Per were obtained *** symmetric multi-color light curves were analyzed by using the Wilson–Devinney(2013)*** photometric solutions suggest that V680 Per is an A-type W UMa contact binary with the mass ratio of q=0.693 and a fill-out factor of f=18.84%with a small temperature difference of 101 *** on all minimum times,the O-C curve was analyzed for the first time in this study.A cyclic oscillation(A3=0.00093 d,T3=4.92 yr)superimposed on a secular decrease(d P/dt=-8.16×10-8 d yr-1)was *** continuous decrease in period is possibly a result of mass transfer from the more massive component to the less massive one,or angular momentum loss due to a magnetic stellar *** of this secular decrease,it is predicted that the degree of contact will become higher,and V680 Per will evolve into a deeper overcontact binary.

关键词： binaries:eclipsing stars:solar-type stars:individual(V680 Per)

Accumulation of biomass and four triterpenoids in two-stage cultured Poria cocos mycelia and diuretic activity in rats

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Chinese Journal of Natural Medicines 2017年第4期15卷 265-270页

作者： HU Gao-Sheng HUANG Chong-Gui ZHANG Yang XIAO Wei jia jing-ming School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Pharmaceutical Research Center Jiangsu Kanion Pharmaceutical Co. Ltd. The Sixth Traditional Chinese Medicines Factory Zhongxin Pharmaceutical Group Ltd.

Poria cocos(Schw.) Wolf, an important medicinal and food fungus, is well known in East Asia. Due to growing market demand, long cultivation period, and consumption of pine trunk during cultivation, developing alternative methods for producing P. cocos and/or its active components is of interest. In the present study, the effects of different culture methods on biomass and accumulation of four triterpenoids were investigated. The ethanol extract of fermented mycelium(EFM) was orally administered to rats. Urine output and concentrations of electrolytes(Na^+, K^+, and Cl^-) were measured. Our results showed that mycelia grew better under continuous shaking culture condition(7.5 g DW·L^(-1)), and higher triterpenoid levels were accumulated in two-stage culture(112 mg·L-1, 2.03%). The optimal starting time of static culture for triterpenoid yield was 4^(th) d after shaking culture. Single administration of middle and high dose of EFM significantly increased urine output, Na^+ and Cl^- excretion, and Na^+/K^+ ratio. These results suggested that ethanol extract of cultured mycelia showed significant diuretic activity in rats and two-stage culture of P. cocos could be an alternative way to produce mycelia and triterpenoids.

关键词： Poria cocos Two-stage culture Diuretic activity Triterpenoids Content determination

Flexible GnRH Antagonist Protocol versus Progestin-primed Ovarian Stimulation (PPOS) Protocol in Patients with Polycystic Ovary Syndrome: Comparison of Clinical Outcomes and Ovarian Response

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Current Medical Science 2019年第3期39卷 431-436页

作者： Zhuo-ni XIAO jia-li PENG jing YANG Wang-ming XU Center for Reproductive Medicine Renmin Hospital of Wuhan University Wuhan 430060China

Polycystic ovary syndrome (PCOS) is one of the most common causes of infertility in women. Progestin-primed ovarian stimulation (PPOS) protocol, which used oral progestin to prevent premature luteinizing hormone (LH) surges in ovarian stimulation, has been proved to be effective and safe in patients with PCOS. The aim of the present study was to compare the efficacy of PPOS protocol with that of the traditional gonadotropin-releasing hormone (GnRH) antagonist protocol in patients with PCOS. A total of 157 patients undergoing in-vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) were recruited into this study. The patients were divided into two groups by the stimulation protocols: the GnRH antagonist protocol group and the PPOS protocol group. There was no significant difference in the clinical characteristics between the two groups. Dose and duration of gonadotropin were higher in the PPOS protocol group. Estradiol levels on the day of human chorionic gonadotropin (hCG) administration were significantly lower in the PPOS protocol group. Fertilization rates and the number of good quality embryos were similar between the two groups. Remarkably, we found 6 patients with moderate ovarian hyperstimulation syndrome (OHSS) in the GnRH antagonist protocol group but 0 in the PPOS protocol group. A total of 127 women completed their frozen embryo transfer (FET) cycles. There were no significant differences between the two groups in terms of clinical pregnancy rate per transfer, implantation rate, first-trimester miscarriage rate and on-going pregnancy rate per transfer. To conclude, PPOS protocol decreased the incidence of OHSS without adversely affecting clinical outcomes in patients with PCOS.

关键词： polycystic ovary syndrome ovarian hyperstimulation syndrome progestin-primed ovarian stimulation GnRH antagonist protocol controlled ovarian hyperstimulation

High-order exceptional points in non-Hermitian Moire lattices

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Frontiers of physics 2019年第5期14卷 81-87页

作者： Yan-Rong Zhang Ze-Zheng Zhang jia-Qi Yuan ming Kang jing Chen MOE Key Laboratory of Weak-Light Nonlinear Photonics School of PhysicsNankai UniversityTianjin 300071China College of Physics and Materials Science Ticmjin Normal UniversityTianjin 300387China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

This study proposes an approach to generate high-order exceptional points (EPs) in non-Herniitian systems.A system comprising a homogenous waveguide is considered wlierein the imaginary part of the refractive index is modulated using a one-dimensional Moire *** gain-loss niodulation couples different lossless waveguide modes,and these hybrid modes can be modeled using a non-Hcnnitian matrix with complex off-diagonal *** indicate that third-order EPs can be produced by the coalescence of two sccond-ordcr ***,the necessary rcquiiGmcnts arc analyzed using couplcd-wavc ccjuations and the physical effects of the singularities are discussed.

关键词： exceptional points non-Hermitian quantum physics quantum optics phase transitions

An overview of rhenium effect in single-crystal superalloys

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Rare Metals 2016年第2期35卷 127-139页

作者： ming Huang jing Zhu Beijing National Center for Electron Microscopy School of Materials Science and Engineering Tsinghua University Beijing 100084 China The State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Beijing 100084 China Laboratory of Advanced Materials (MOE) School of Materials Science and Engineering Tsinghua University Beijing 100084China

Nickel-based single-crystal superalloys are the key materials for the manufacturing and development of advanced aeroengines. Rhenium is a crucial alloying element in the advanced nickel-based single-crystal superalloys for its special strengthening effects. The addition of Re could effectively enhance the creep properties of the single-crystal superalloys; thus, the content of Re is considered as one of the characteristics in different-generation single-crystal superalloys. Owing to the fundamental importance of rhenium to nickel-based single-crystal superalloys, much progress has been made on understanding of the effect of rhenium in the single-crystal superalloys. While the effect of Re doping on the nickelbased superalloys is well documented, the origins of the socalled rhenium effect are still under debate. In this paper,the effect of Re doping on the single-crystal superalloys and progress in understanding the rhenium effect are reviewed. The characteristics of the d-states occupancy in the electronic structure of Re make it the slowest diffusion elements in the single-crystal superalloys, which is undoubtedly responsible for the rhenium effect, while the postulates of Re cluster and the enrichment of Re at the c/c0 interface are still under debate, and the synergistic action of Re with other alloying elements should be further ***, the interaction of Re with interfacial dislocations seems to be a promising explanation for the rhenium effect. Finally, the addition of Ru could help suppress topologically close-packed（TCP） phase formation and strengthen the Re doping single-crystal *** the mechanism of rhenium effect will be beneficial for the effective utilization of Re and the design of low-cost single-crystal superalloys.

关键词： Nickel-based single-crystal superalloys Rhenium effect Creep Strengthening mechanism Re cluster Interfacial dislocations