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基于UPLC-Q-Orbitrap-MS的鹿角方化学成分及组织分布分析

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中国实验方剂学杂志 2024年第8期30卷 148-156页

作者：张建伟刘伟沈沁刘力上海中医药大学附属曙光医院国家中医药管理局中药制剂三级实验室上海201203

目的:基于超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(UPLC-Q-Orbitrap-MS),定性分析鹿角方中的化学成分及其组织分布。方法:采用ACQUITY UPLC®BEH C_(18)色谱柱(2.1 mm×100 mm,1.7μm),流动相0.1%甲酸水溶液(A)-甲醇(B)梯度洗脱... 详细信息

目的:基于超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(UPLC-Q-Orbitrap-MS),定性分析鹿角方中的化学成分及其组织分布。方法:采用ACQUITY UPLC®BEH C_(18)色谱柱(2.1 mm×100 mm,1.7μm),流动相0.1%甲酸水溶液(A)-甲醇(B)梯度洗脱(0~2 min,4%B;2~6 min,4%~12%B;6~38 min,12%~70%B;38~38.5 min,70%B;38.5~39 min,70%~95%B;39~43 min,95%B;43~43.1 min,95%~4%B;43.1~45 min,4%B),流速0.3 m L·min^(-1),柱温40℃,进样量5μL,采用电喷雾离子源(ESI),正负离子全扫模式采集数据,扫描范围m/z.100~1500,碰撞能量10、20、40 e V。通过保留时间、精确相对分子质量、二级质谱碎片离子等信息,结合自建数据库,与对照品及文献数据进行比对,对鹿角方中化学成分及组织分布进行分析。结果:从鹿角方中共鉴定或推测出260个化合物,包括黄酮类156个,萜类43个,香豆素类18个,有机酸类13个,苯乙醇类7个,生物碱类7个,其他类16个,其中68种通过对照品比对鉴定。组织分布结果显示,分别在血、心脏、肝脏、肾脏中检测到原型成分100、143、129和126个。结论:该研究对鹿角方中的化学成分及组织分布进行了较全面的分析鉴定,可为鹿角方及其处方饮片的质量控制、临床应用、药代动力学、药效物质基础研究提供科学依据。

关键词：鹿角方淫羊藿女贞子补骨脂山茱萸陈皮化学成分组织分布超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(UPLC-Q-Orbitrap-MS)

Experimental study of compressible boundary layer on a cone at angles of attack

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Acta Mechanica Sinica 2009年第3期25卷 325-333页

作者： A.Maslov D.Bountin A.Shiplyuk A.Sidorenko Q.shen z.Bi Khristianovich Institute of Theoretical and Applied Mechanics(ITAM)and Novosibirsk State University China Academy of Aerospace Aerodynamics(CAAA)

Experimental study was conducted for boundarylayers on a sharp 5° half-angle cone of 400mm length at angles of attack. The model was tested in the T-326 hypersonic wind tunnel （ITAM） at freestream Mach number M = 5.95. Mean and fluctuation wall characteristics of the boundary layer are measured at 0°, 2°, 3° and 4° angles of attack for different stagnation pressures. Pulsation measurements are carried out by means of ALTP sensor. Pressure and temperature distributions along the model are obtained, and transition beginning and end locations have been found. Boundary layer stabiliz.tion with the increase of angle of attack and the decrease of stagnation pressure is observed. High frequency pulsations inherent to hypersonic boundary layer （second mode） have been detected.

关键词： Compressible boundary layer Transition,Experimental study

Grain refinement mechanism of Mg-3Sn-1Mn-1La alloy during accumulative hot rolling

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Journal of Materials Science & Technology 2021年第32期91卷 251-261页

作者： z.Y.z.ao R.G.Guan Y.F.shen P.K.Bai School of Materials Science and Engineering North University of ChinaTaiyuan 030051China bEngineering Research Center of Continuous Extrusion Ministry of EducationDalian Jiaotong UniversityDalian 116028China Key Laboratory for Anisotropy and Texture of Materials Northeastern UniversityShenyang 110004China

We elucidate the effect of lanthanum(La) on the grain refinement of Mg-3 Sn-1 Mn alloy during accumulative hot rolling. The lath-shaped Mg_(2) Sn phase in the Mg-3 Sn-1 Mn alloy is firstly broken and spheroidiz.d,and then the siz. increases and coarsens with the increase of rolling reduction, most of Mg_(2) Sn move from grain boundary to grain and are homogeneously distributed within the matrix. However, the plate-shaped Mg Sn La compound in Mg-3 Sn-1 Mn-1 La gradually becomes fine, spheroidiz.d, and homogeneously distributed. The grain siz.s of Mg-3 Sn-1 Mn and Mg-3 Sn-1 Mn-1 La alloys become fine through dynamic recrystalliz.tion(DRX), though the grain refinement of Mg-3 Sn-1 Mn-1 La alloy is better compared to the Mg-3 Sn-1 Mn alloy. A large number of uniformly distributed spherical Mg Sn La compounds pin the dislocations, thus increasing the dislocation density. Hence, the driving force for DRX increases and promotes the formation of deformation bands and more twins, providing the sites for DRX nucleation and growth.

关键词： Mg alloy Grain refinement Dynamic recrystalliz.tion Accumulative hot rolling

Effects of Mixing Volume and Initial Particle Siz. Distribution of Fly Ash on Pore Solution of Cement Paste

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武汉理工大学学报 2010年第17期32卷 112-116页

作者： SHUI z.H DUAN P shen C H School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Center of Materials Research and Analysis Wuhan University of TechnologyWuhan 430070China

The effects of fly ash with different mixing volume and different particle siz.s on pore solution of cement-based materials were studied. The pore solution was extracted by squeez.ng at scheduled ages. The particle siz. distribution of fly ash was classified as smaller than 45 μm and 45～80 μm,and the mixing volume was classified as 10% and 20%. The concentrations of K+,Na+ and Ca2+ were measured using Inductively Coupled Plasma Emission Spectrometer (ICP),and the pH was measured by acid-base titration. The results indicate that the concentrations of various ions were prompted at the initial time of the hydration. With further hydration,ion concentrations of K+ and Na+ raise again and finally stabiliz.d,but there is a certain decline on Ca2+ later on. It also shows that fly ash exhibited great effect on the hydration of cement,it can lower the concentration of Ca2+ and pH of the pore solution,but raise the concentrations of K+ and Na+. More importantly,ion concentrations of K+,Na+ and Ca2+ reduced with smaller particle siz.s of fly ash.

关键词： cement-based materials pore solution ion concentration squeez.

Impact of post-acute COVID-19 exercise training on cardiovascular autonomic function in amateur runners: A self-controlled longitudinal study

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中华医学杂志(英文版) 2024年第19期137卷 2024 Sep 5页

作者： Xu shen Xian Hong Liao Yue z.ang Haowei Xia Ling Liu Yixin Tong Nanwei Department of Endocrinology and Metabolism Laboratory of Diabetes and Metabolism Research National Clinical Research Center for Geriatrics West China Hospital Sichuan University Chengdu Sichuan China Department of Geriatrics National Clinical Research Center for Geriatrics West China Hospital Sichuan University Chengdu Sichuan China West China School of Medicine Sichuan University Chengdu Sichuan China Meishan Center for Disease Control and Prevention Meishan Sichuan China

Diagnose and treatment for Type D congenital esophageal atresia with tracheoesophageal fistula

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Pediatric Investigation 2024年第1期8卷 37-43页

作者： Dingding Wang Yong z.ao Yanan z.ang Kaiyun Hua Yichao Gu Shuangshuang Li Junmin Liao shen Yang Ting Yang Jiawei z.ao Jinshi Huang Department of Neonatal Surgery Beijing Children’s HospitalCapital Medical UniversityNational Center for Children’s HealthBeijingChina

Importance:Type D esophageal atresia(EA)with tracheoesophageal fistula(TEF)is characteriz.d by EA with both proximal and distal *** is a rare congenital anomaly with a very low ***:To investigate diagnostic and treatment strategies for this rare ***:We retrospectively reviewed the clinicopathological features of patients with EA/TEF treated at our institution between January 2007 and September ***:Among 386 patients with EA/TEF,14(3.6%)had type D EA/*** two patients were diagnosed with proximal TEF *** patients were diagnosed *** patients were missed for diagnosis during the initial surgery but was later confirmed by *** the neonatal period,seven patients underwent a one-stage repair of proximal and distal TEF via thoracoscopy or *** to missed diagnosis and other reasons,the other 7 patients underwent two-stage surgery for repair of the proximal TEF,including cervical incision and *** of the 14 patients experienced postoperative complications including anastomotic leakage,pneumothorax,esophageal stricture,and *** who underwent one-stage repair of distal and proximal TEF during the neonatal period showed a higher incidence of anastomotic leak(4/7).In contrast,only one of seven patients with two-stage repair of the proximal TEF developed an anastomotic ***:Type D EA/TEF is a rare condition,and proximal TEFs are easily *** may aim to diagnose and determine the correct surgical approach.A cervical approach may be more suitable for repairing the proximal TEF.

关键词： Diagnosis Therapy Tracheoesophageal fistula Type D congenital esophageal atresia

Mechanical properties of Al/a-C nanocomposite thin films synthesiz.d using a plasma focus device

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Chinese Physics B 2014年第2期23卷 353-358页

作者： z.A.Umar R.S.Rawat R.Ahmad A.K.Kumar Y.Wang T.Hussain z.Chen L.shen z.z.ang NSSE National Institute of EducationNanyang Technological University Department of Physics GC University Center for Advanced Studies in Physics (CASP) GC University School of Materials Science and Engineering Nanyang Technological University Institute of Materials Research and Engineering ASTAR (Agency for ScienceTechnology and Research)3 Research Link

The Al/a-C nanocomposite thin films are synthesiz.d on Si substrates using a dense plasma focus device with alu- minum fitted anode and operating with CH4/Ar admixture. X-ray diffractometer results confirm the formation of metallic crystalline Al phases using different numbers of focus shots. Raman analyses show the formation of D and G peaks for all thin film samples, confirming the presence of a-C in the nanocomposite thin films. The formation of Al/a-C nanocomposite thin films is further confirmed using X-ray photoelectron spectroscopy analysis. The scanning electron microscope results show that the deposited thin films consist of nanoparticles and their agglomerates. The siz.s of th agglomerates increase with increasing numbers of focus deposition shots. The nanoindentation results show the variations in hardness and elastic modulus values of nanocomposite thin film with increasing the number of focus shots. Maximum values of hardness and elastic modulus of the composite thin film prepared using 20 focus shots are found to be about 10.7 GPa and 189.2 GPa, respectively.

关键词： dense plasma focus X-ray photoelectron spectroscopy field emission scanning electron micro- scope elastic modulus

Ab initio valence-space in-medium similarity renormaliz.tion group calculations for neutron-rich P,Cl,and K isotopes

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Chinese Physics C 2024年第7期48卷 181-190页

作者：谢萌冉沈留媛李健国李红蕙袁琪左维 Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Neutron-rich P,Cl,and K isotopes,particularly those with neutron numbers of approximately N=28,have attracted extensive experimental and theoretical *** utiliz. the ab initio valence-space in-medium similarity renormaliz.tion group approach,based on chiral nucleon-nucleon and three-nucleon forces,to investigate the exotic properties of these *** calculations of the low-lying spectra are performed.A key finding is the level inversion between 3/2_(1)^(+)and 1/2_(1)^(+)states in odd-A isotopes,attributed to the inversion ofπ0xod_(3/2) andπls_(1/2) single-particle *** ab initio calculations,which incorporate the three-nucleon forces,correlate closely with existing experimental *** calculations of effective proton single-particle energies provide deeper insights into the shell evolution for z.14 and 16 *** results indicate that the three-body force plays important roles in the shell evolution for z.14 and 16 sub-shells with neutron numbers ranging from 20 to ***,systematic ab initio calculations are conducted for the low-lying spectra of odd-odd *** results correspond with experimental data and provide new insights for future research into these isotopes up to and beyond the drip line.

关键词： ab initio calculations shell evolution low-lying spectra

Locally unlocks prodrugs by radiopharmaceutical in tumor for cancer therapy

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Science Bulletin 2024年第17期69卷 2745-2755页

作者： Changlun Wang Mengxin Xu z.hang z.ang Senhai z.ng Siyong shen z.xuan Ding Junyi Chen Xi-Yang Cui z.ibo Liu Beijing National Laboratory for Molecular Sciences Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental ScienceKey Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Peking University-Tsinghua University Center for Life Sciences Peking UniversityBeijing 100871China Changping Laboratory Beijing 102206China Key Laboratory of Carcinogenesis and Translational Research of Ministry of Education Key Laboratory for Research and Evaluation of Radiopharmaceuticals of National Medical Products AdministrationDepartment of Nuclear MedicinePeking University Cancer HospitalBeijing 100142China

Chemotherapy is the first-line treatment for cancer, but its systemic toxicity can be severe. Tumorselective prodrug activation offers promising opportunities to reduce systemic toxicity. Here, we present a strategy for activating prodrugs using radiopharmaceuticals. This strategy enables the targeted release of chemotherapeutic agents due to the high tumor-targeting capability of radiopharmaceuticals. [^(18)F]FDG(2-[^(18)F]-fluoro-2-deoxy-D-glucose), one of the most widely used radiopharmaceuticals in clinics, can trigger Pt(IV) complex for controlled release of axial ligands in tumors, it might be mediated by hydrated electrons generated by water radiolysis resulting from the decay of radionuclide18F. Its application offers the controlled release of fluorogenic probes and prodrugs in living cells and tumor-bearing mice. Of note,an OxaliPt(IV) linker is designed to construct an [^(18)F]FDG-activated antibody-drug conjugate(Pt-ADC).Sequential injection of Pt-ADC and [^(18)F]FDG efficiently releases the toxin in the tumor and remarkably suppresses the tumor growth. Radiotherapy is booming as a perturbing tool for prodrug activation,and we find that [^(18)F]FDG is capable of deprotecting various radiotherapy-removable protecting groups(RPGs). Our results suggest that tumor-selective radiopharmaceutical may function as a trigger, for developing innovative prodrug activation strategies with enhanced tumor selectivity.

关键词： Prodrugactivation Radiopharmaceutical Radiochemistry [^(18)F]FDG Platinum(IV)prodrug