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An Improved Method of Simultaneous Determination of Four Bioactive Compounds in Evodiae Fructus Using Ionic Liquids as Mobile Phase Additives in High Performance Liquid Chromatography

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Chemical Research in Chinese Universities 2017年第4期33卷 552-558页

作者： bian min TIAN Ling YAO Cheng College of Chemistry and Molecular Engineering Nanj'ing Tech University Nanjing 211800 P. R. China

There are many compounds with different structures and chemical properties in Evodiae Fructus. It is hard to simultaneously determine the bioactive compounds by high performance liquid chromatography（HPLC）. A new method was proposed for four bioactive compounds（synephrine, limonoids, evodiamine and rutecarpine） to be separated completely and determined accurately using ionic liquids（ILs） as mobile phase additives. The mechanism and the effect of the ILs for changing the chromatographic behaviors of the four compounds were studied by systemati- cally changing the pH value of mobile phase, the types and concentrations of ILs as well as the concentrations of phosphate buffer. The chromatographic behaviors of the analytes with a mobile phase containing ILs complied with the stoichiometric displacement model for retention（SDM-R）. All results demonstrate the dual nature of ionic liquids, which are competitive adsorption and ion-pair agent. Meanwhile, excellent linearity was observed for all the com- pounds with correlation coefficients between 0.9992 and 0.9998. The limit of detection and the limit of quantification of the four compounds varied from 0.47μg/mL to 0.87 μg/mL and from 1.79 μg/mL to 2.44μg/mL, respectively. Three kinds of Evodiae Fructus processed through different methods were analyzed via the method. The result shows that the contents of evodiamine and rutecarpine as the two main active compounds by processing with vinegar and salt are obviously higher than those of the raw products.

关键词： Evodiae Fructus Ionic liquid Mobile phase additive High performance liquid chromatography(HPLC) Processed Evodiae Fructus

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Diversity of Nitrogenase Systems in Diazotrophs

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Journal of Integrative Plant Biology 2006年第7期48卷 745-755页

作者： Ying Zhao Shao-min bian Hui-Na Zhou Ju-Fu Huang Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China School of Graduate the Chinese Academy of Sciences Beijing 100039 China

Nitrogenase is a metalloprotein complex that catalyses the reaction of biological nitrogen fixation. At least three genetically distinct nitrogenase systems have been confirmed in diazotrophs, namely Nil, Vnf, and Anf, in which the active-site central metals are Mo, V, and Fe, respectively. The present review summarizes progress on the genetic, structural, and functional investigations into the three nitrogenases and discusses the possibility of the existence of other novel nitrogenases.

关键词： diazotroph FeMo-cofactor and cofactors substituted for Mo nitrogenase system P-cluster.

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Synthesis of novel chiral stationary phases for high-performance liquid chromatography

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Chinese Chemical Letters 2007年第4期18卷 461-464页

作者： Xu Lin Tan Shi Cong Hou Qing Hua bian min Wang College of Science China Agricultural University Beijing 100094 China

Three novel chiral selectors 4a-c were synthesized from （S）-amino acids and （R）-1-phenyl-2-（4-methylphenyl）ethylamine. 4a-c were connected to 3-aminopropylsilanized silica gel to be used as the chiral stationary phase for HPLC. Five amino acid derivatives and two pyrethroid insecticides were fairly resolved on these three new chiral stationary phases under normal phase condition.

关键词： Enantioseparation Chiral stationary phase Amino acid derivatives Pyrethroid insecticides

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Regional Differences and Characteristics of Soil Organic Carbon Density Between Dry Land and Paddy Field in China

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Agricultural Sciences in China 2007年第8期6卷 981-987页

作者： XU Quan RUI Wen-yi bian Xin-min ZHANG Wei-jian Institute of Applied Ecology Nanjing Agricultural University Nanjing 210095 P.R.China

Study on the regional characteristics of soil organic carbon （SOC） density in farmland will not only contribute greatly to the technique of soil productivity enhancement, but also give evidences of technique selection and policy making for carbon sequestration in soils. Based on the second national soil survey of China, the situation of SOC density in the plow layer of farmland was analyzed under different land use patterns. Results showed that SOC density in the plow layer was about 3.15 kg m^-2 in average ranging from 0.81 to 12.68 kg m^-2. The highest density was found in the southeastern region with an average of 3.63 kg ma, while the lowest occurring in the northwestern region with an average of 3.00 kg m^-2. The variation coefficient of SOC density in the plow layer of farmland was 57%, which was 35% lower than that of non-farmland soils. Compared to SOC density in the dry land, SOC density in paddy soils was 13% higher with a lower variation coefficient between different regions. In addition, the relationships between the climatic factors （annual average temperature and precipitation） and SOC density were lower in farmland than those in non-farmland soils, as well as lower in paddy soils than those in dry land of farmland. These results suggest that anthropogenic disturbances have great impacts on SOC density in farmland soils, especially in paddy soils, indicating that Chinese rice cropping may contribute greatly to the SOC stability and sequestration in paddy field.

关键词： land use pattern organic carbon density carbon sequestration regional difference global change

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Purification and Characterization of a New Heme-Binding （HBP59） from the Mutant Strain DJ35 of Azotobacter vinelandii

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Journal of Integrative Plant Biology 2007年第3期49卷 336-342页

作者： Shao-min bian Huang-Ping Wang Hui-Na Zhou Ying Zhao Jian-Feng Zhao Ju-Fu Huang Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Bioengineering College Fujian Normal University Fuzhou 350007 China Graduate School the Chinese Academy of Sciences Beijing 100039 China

A new protein, an approximately 59-kDa monomer containing iron atoms, was first isolated from the mutant strain DJ35 of Azotobacter vinelandii Llpmann. After analysis by matrix-assisted laser desorptlon ionization time-of-flight mass spectrometry, the protein was Identified as the product of a predicted gene. Thus, the protein was tentatively called HBP59. Its absorption spectra （ABS） In the reduced state exhibited three peaks at 421,517, and 556 nm and the maximal peak was shifted from 421 to 413 nm after exposure of HBP59 to air. The Soret circular dichrolsm （CD） spectrum of HBP59 In the reduced state displayed four positive peaks at 364, 382, 406, and 418 nm and two negative peaks at 398 and 433 nm; the △ε （CD extinction coefficient） values of these peaks were found to be 0.92, 0.58, 0.87, 0.72, -0.65 and -1.12 L/mol per cm, respectively. Titration with heme showed that the protein has 0.1 heme molecules/protein molecule. After HBP59 had fully Interacted with heme, Its maximal ABS value and Soret CD Intensity were increased by approximately 10-fold compared with values before Interaction. Therefore, It seems that one molecule of HBP59 can be interacted with only one heme. These results indicate that HBP59 contains heme with low spin and may be Involved In heme utilization or adhesion.

关键词： absorption spectra Azotobacter vinelandii characterization by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) circular dichroism spectra and titration heme-binding protein (HBP59) mutant strain DJ35 purification

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ON THE ORIGIN OF TURBULENT SECONDARY FLOW IN A STRAIGHT DUCT OF NON-CIRCULAR CROSS-SECTION

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Journal of Hydrodynamics 1993年第3期5卷 98-111页

作者： Zhao, Lie Wang, Famin bian, Yungui Yu, Xin Inst of Mechanics Academia Sinica Beijing China

The origin of turbulent secondary flow in a straight duct of non-circular cross-section was discussed from a theoretical standpoint and examined from a numerical simulation of the turbulent flow in a square duct. It was reached that the driving force of such secondary flow comes from the second-order terms of the difference in gradients of normal and transverse Reynolds stresses in the axial vorticity equation. The present results obtained compare well with available experimental results for both primary and secondary flow quantities.

关键词： Ducts Pipe flow Simulation

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Identification of Contaminations Hiding Beneath the α- and β-Subunits of Partially Purified Nitrogenase MoFe Protein on the Sodium Dodecyl Sulfate Gel

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Journal of Integrative Plant Biology 2005年第11期47卷 1364-1371页

作者： Hui-Na ZHOU Ying ZHAO Shao-min bian Jian-Feng ZHAO Fei REN Huang-Ping WANG Ju-Fu HUANG Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China China Agricultural University Beijing 100094 China Fujian Normal University Fuzhou 350007 China

To identify the unknown proteins that would contaminate the α- and β-subunits of nitrogenase MoFe protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE）, the partially purified MoFe protein （Avl） preparation was obtained from Azotobacter vinelandii Lipmann OP by chroma- tography on DEAE-cellulose （DE52） and Sephacryl S-200 columns and analyzed by PAGE and matrix- assisted laser desorption/ionization time-of-flight （MALDI-TOF） mass spectrometry. The Av 1 preparation was shown to have two main bands at the position of the α- and β-subunits of crystalline Avl on the SDS gel. However, on the anoxic native PAGE, in addition to the Avl band, the preparation was shown to have three other main bands that migrated slower than Av 1. Of these three main bands, the protein with the fastest migration was identified as bacterioferritin elsewhere. The proteins on the other two bands, termed Upper and Middle, were suggested to be two different homopolymers with the same apparent subunit electrophoretic mobilities as the α- and β-subunits of Avl, respectively. By analysis of MALDI-TOF mass spectrometry, the Upper was identified as GroEL, which belongs to the heat shock protein 60 family, and the Middle was identified as glucose-6-phosphate isomerase （PGI）. In our preparation, anoxic native electrophoresis indicated that GroEL was composed of 14 identical subunits and that PGI was composed of 10 identical subunits. This is the first report of PGI, with so many subunits. The contaminating proteins in the Av 1 preparation, mainly GroEL and PGI, could be totally or partially removed from Av 1 if the shoulders and center of the elution peak were collected separately from the Sephacryl S-200 column and the center fraction was purified further by Q-Sepharose developed with an NaC1 concentration gradient. Thus, Avl with more than 90% purity was obtained. Obviously, this modified method is useful for the purification of mutant MoFe proteins with a high purity.

关键词： Azotobacter vinelandii chaperonin GroEL glucose-6-phosphate isomerase nitrogenase Av 1.

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股骨近端防旋髓内钉治疗股骨转子间骨折

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临床骨科杂志 2020年第3期23卷 402-405页

作者：卞敏凯常州市第三人民医院骨科江苏常州213001

目的观察股骨近端防旋髓内钉(PFNA)治疗股骨转子间骨折的疗效,分析影响术后髋关节功能恢复的因素。方法采用PFNA治疗102例股骨转子间骨折患者。末次随访时,采用髋关节功能Harris评分标准评价患者髋关节功能恢复情况,根据优、良、可、差... 详细信息

目的观察股骨近端防旋髓内钉(PFNA)治疗股骨转子间骨折的疗效,分析影响术后髋关节功能恢复的因素。方法采用PFNA治疗102例股骨转子间骨折患者。末次随访时,采用髋关节功能Harris评分标准评价患者髋关节功能恢复情况,根据优、良、可、差分为恢复良好组和恢复较差组,采用logistic回归分析影响髋关节功能恢复的因素。结果患者均获得随访,时间11~13周。末次随访时,髋关节功能恢复良好组76例(74.5%),恢复较差组26例(25.5%)。患者年龄、ASA分级、骨折分型、骨质疏松程度、尖顶距(TAD)、合并内侧皮质损伤和术后4周固定钉滑脱量两组比较差异均有统计学意义(P<0.05)。Logistic回归分析显示,影响PFNA术后髋关节功能的因素依次为骨折分型、骨质疏松程度、TAD、合并内侧皮质损伤、术后4周固定钉滑脱量、年龄和ASA分级。结论PFNA治疗股骨转子间骨折疗效确切,其影响术后髋关节功能恢复的影响因素较多,包括骨折分型、骨质疏松程度、TAD、合并内侧皮质损伤、术后4周固定钉滑脱量、年龄和ASA分级等,临床应依据各影响因素采取针对性措施,促进髋关节功能恢复,提高生活质量。

关键词：股骨转子间骨折股骨近端防旋髓内钉髋关节功能影响因素

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Activation In Vitro of Mutant MoFe Proteins from Azotobacter vinelandii by Reconstituent Solutions

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Journal of Integrative Plant Biology 2006年第5期48卷 567-572页

作者： Huang-Ping Wang Ying Zhao Shao-min bian Hui-Na Zhou Zhi-Gang Zhang Jin-Mao Zhu Ju-Fu Huang Bioengineering College Fujian Normal University Fuzhou 350007 China Key Laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany the Chinese Academy of Sciences Beijing 100093 China College of Life Sciences Northwest University Xi＇an 710069 China

nifB-MoFe protein （nifB-Av1）, AnifE MoFe protein （△nifE Av1） and AnifZ MoFe protein （△nifZ Av1） were obtained by chromatography on DE52, Sephacryl S-300 and Q-Sepharose columns from nifB point-mutated, nifE deleted and nifZ deleted mutant stains （UW45, DJ35 and DJ194） of Azotobacter vinelandii Llpmann, respectively. When complemented with nltrogenase Fe protein （Av2）, AnifZ Av1 had partial activity and both nifB-Avl and △nifE Av1 had hardly any activity, but could be obviously activated by FeMoco extracted from wild-type MoFe protein （OP Av1） or △nifZ Av1. After being Incubated with excess O-phenanthrollne （O-phen） for 150 mln at 30 ℃ and subjected to chromatography on a Sephadex G-25 column In an Ar atmosphere, nifB- Av1C, △nifE Av1C and △nifZ Av1C were obtained, respectively. Based on a calculation of Fe atoms In the Ophen-Fe compound with ε 512nm = 11 100, lost Fe atoms of nifB-Av1, △nifE Av1 and △nifZ Av1 were estimated to be 1.35, 2.89 and 8.44 per molecule of protein, respectively. As a result of the Fe loss, △nifZ Av1 loses Its original activity. In the presence of both MgATP and Av2, these Fe-loslng proteins, but not the original proteins untreated with O-phen, could be significantly activated by reconstltuent solution （RS） composed of dlthlothreltol, ferric homocltrate, Na2S and Na2MoO4, or K2CrO4, or KMnO4. But In the absence of MgATP or Av2, the activation did not occur, with the exception that △nifZ AvlC was partially activated, and the activity was only 17%. These findings Indicate that：（I） △nifZ Avl with half P-cluster content Is somewhat different from FeMoco-deflclent nifB-Avl and ,△nifE Av1 with respect to protein conformation either before or after treatment with O-phen; （11） full activation of these proteins with RS requires pretreatment with O-phen and the simultaneous presence of MgATP and Av2.

关键词： activation in vitro by reconstituent solutions Azotobacter vinelandii mutant MoFe protein nifB^-,△nifE and △nifZ mutants.

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A Comparative miRNAome Analysis Reveals Seven Fiber Initiation-Related and 36 Novel miRNAs in Developing Cotton Ovules

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Molecular Plant 2012年第4期5卷 889-900页

作者： Zheng-ming Wang Wei Xue Chun-Juan Dong Long-Guo Jin Shao-min bian Chuan Wang Xiu-Yun Wu Jin-Yuan Liu Laboratory of Molecular Biology and MOE Laboratory of Protein Science School of Life SciencesTsinghua UniversityBeijing 100084China

An increasing number of microRNAs （miRNAs） have been shown to play crucial regulatory roles in the process of plant development. Here, we used high-throughput sequencing combined with computational analysis to characterize miRNAomes from the ovules of wild-type upland cotton and a fiberless mutant during fiber initiation. Comparative miR- NAome analysis combined with northern blotting and RACE-PCR revealed seven fiber initiation-related miRNAs expressed in cotton ovules and experimentally validated targets of these miRNAs are involved in different cellular responses and metabolic processes, including transcriptional regulation, auxin and gibberellin signal transduction, actin bundles, and lignin biosynthesis. This paper describes a complex regulatory network consisting of these miRNAs expressed in cotton ovules to coordinate fiber initiation responses. In addition, 36 novel miRNAs and two conserved miRNAs were newly iden- tified, nearly doubling the number of known cotton miRNA families to a total of 78. Furthermore, a chromatin remodeling complex subunit and a pre-mRNA splicing factor are shown for the first time to be miRNA targets. To our knowledge, this study is the first systematic investigation of fiber initiation-related miRNAs and their targets in the developing cotton ovule, deepening our understanding of the important regulatory functions of miRNAs in cotton fiber initiation.

关键词： Cotton ovules fiber initiation high-throughput sequencing molecular characterization newly identifiedmiRNAs.

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