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Expression patterns of OCT4, NANOG, and SOX2 in goat preimplantation embryos from in vivo and in vitro

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Journal of Integrative Agriculture 2015年第7期14卷 1398-1406页

作者： YU Xiao-li ZHAO Xiao-e wang hua-yan MA Bao-hua College of Veterinary Medicine Northwest A&F University Key Laboratory of Animal Biotechnology Ministry of Agriculture

The transcription factors, including OCT4, NANOG, and SOX2, played crucial roles in the maintenance of self-renewal and pluripotency in embryonic stem cells （ESCs）. They expressed in preimplantation mammalian development with spa- tio-temporal pattern and took part in regulation of development. However, their expression and roles in goat had not been reported. In the present study, the expression of OCT4, NANOG, and SOX2 in goat preimplantation embryos both in vivo and in vitro were detected by real-time RCR and immunofluorescence. For in vivo fertilized embryos, the transcripts of OCT4, NANOG, and SOX2 could be detected from oocytes to blastocyst stage, their expression in morula and blastocyst stages was much higher than other stage. OCT4 protein was detected from oocyte to blastocyst, but the fluorescence was more located-intensive with nuclei from 8-cell stage, its expression present in both inner cell mass （ICM） and trophoblast cells （TE） at blastocyse stage. NANOG protein was similar to OCT4, the signaling of fluorescence completely focused on cell nuclei, while the SOX2 firstly showed nuclei location in morula. Comparing to in vivo fertilized embryo, the mRNA of these three transcription factors could be detected at 8-cell stage in parthenogenetic embryos （in vitro）. Thereafter, the expressional level rose gradually along with embryo development. The locations of OCT4 and NANOG proteins were similar to in vivo fertilized embryos, and they located in cell nuclei from morula to blastocyst stage, while SOX2 protein firstly could be detected in cell nuclei at 8-cell stage. These differences suggested that OCT4, NANOG, and SOX2 played different function in regulating development of goat preimplantation embryos. These results may provide a novel insight to goat embryo development and be useful for goat ESCs isolation.

关键词： goat OCT4 NANOG SOX2 embryo expression pattern

Theoretical Studies on the Iodine-catalyzed Nucleophilic Addition of Acetone with Five-membered Heterocycles

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Chemical Research in Chinese Universities 2008年第4期24卷 520-524页

作者： wang yan-hua LI Li CHEN Xue-song College of Biology and Environment Engineering Zhejiang Shuren University Hangzhou 310015 P. R. China

The iodine-catalyzed nucleophilic addition reactions of pyrrole, furan, or thiophene with acetone were studied in gas and solvent by the density functional theory at the level of Lanl2DZ^＊. It was seen that the halogen bond between iodine and carbonyl oxygen appeared to have an important catalytic effect on such reactions, and the first iodine molecule maximally diminished the barrier height by 41 kJ/mol, while the second iodine molecule could not improve such reactions largely. It was concluded that the C2-addition was generally more favorable than the C3-addition for the three heterocycles; however, iodine considerably more effectively catalyzed the C3-addition than the C2-addition for pyrrole. It was also revealed by PCM calculation that the iodine-catalyzed nucleophilic additions occurred more easily in solvent than in gas, which explained the experiment performed by Bandgar et al..

关键词： Halogen bond, Catalytic effect Nucleophilic addition Density functional theory

Loss of Responsiveness to Osmotic Stress in Maize Root:the Effect of Water Channel Blocker HgCl_2

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Agricultural Sciences in China 2010年第8期9卷 1230-1235页

作者： ZHU Jian-jun BAI Xin-fu ZHANG Ping wang yan-hua College of Life Sciences Ludong University Yantai 264025 P.R.China

In order to investigate the effect of water channel blocker HgCl2 on the hydraulic resistance in roots of maize seedlings, a xylem pressure probe was used to monitor the changes in root xylem pressure in response to NaCl- or mannitol-induced osmotic stresses before and after the application of HgCl2. When the maize roots were subjected to 500 umol L-1 HgCl2 in root bathing solution, not only a considerable decline in xylem pressure （increase in xylem tension） was observed, but the loss of responsiveness of the plant to both salt- and mannitol-induced osmotic stresses in terms of xylem pressure change was seen as well when the transpiration rate of the plant was not significantly changed. The results are similar but different from the reversed osmosis by the Fenton reaction in the internodes of Chara coralline, showing that the mechanisms of water transport across cell membrane in plant roots are far more complicated than expected.

关键词： aquaporin maize root mercury chloride xylem pressure osmotic stress

Laboratory Testing of Magnetic Tracers for Soil Erosion Measurement

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Pedosphere 2011年第3期21卷 328-338页

作者： HU Guo-Qing DONG Yuan- Jie wang Hui QIU Xian-Kui wang yan-hua College of Resources and Environment Shandong Agricultural University Tai'an 271018 (China)

Soil erosion, which includes soil detachment, transport, and deposition, is one of the important dynamic land surface processes. The magnetic tracer method is a useful method for studying soil erosion processes. In this study, five types of magnetic tracers were made with fine soil, fly ash, cement, bentonite, and magnetic powder （reduced iron powder） using the method of disk granulation. The tracers were uniformly mixed with soil and tested in the laboratory using simulated rainfall and inflow experiments to simulate the interrill and rill components of soil erosion, in order to select one or more tracers which could be used to study detachment and deposition by the erosive forces of raindrops and surface flow of water on a slope. The results showed that the five types of magnetic tracers with high magnetic susceptibility and a wide range of sizes had a range of 0.99-1.29 gcm-3 in bulk density. In the interrill and rill experiments, the tracers FC1 and FC2 which consisted of fly ash and cement at ratios of 1：1 and 2：1, respectively, were transported in phase with soil particles since the magnetic susceptibility of sediment approximated that of the soil which was uneroded and the slopes of the regression equations between the detachment of sediment and magnetic tracers FC1 and FC2 were very close to the expected value of 20, which was the original soil/tracer ratio. The detachment and deposition on slopes could be accurately reflected by the magnetic susceptibility differences. The change in magnetic susceptibility depended on whether deposition or detachment occurred. However, the tracer FS which consisted of fine soil and the tracers FB1 and FB2 which consisted of fly ash and bentonite at ratios of 1：1 and 2：1, respectively, were all unsuitable for soil erosion study since there was no consistent relationship between sediment and tracer detachment for increasing amounts of runoff. Therefore, the tracers FC1 and FC2 could be used to study soil erosion by water.

关键词： magnetic susceptibility interrill erosion rill erosion runoff sediment

Polyacrylamide hydrogels with phenylboronic acid moieties for the imprinting of proteins

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Chinese Chemical Letters 2010年第12期21卷 1487-1489页

作者： yan wang Zhi hua Chai Hong yan He Yi Zhe Jiang Guo Qi Fu Key Laboratory of Functional Polymer Materials of Ministry of Education Institute of Polymer Chemistry Nankai University Tianjin 300071 China

In this letter,N-acryloyl-3-aminophenylboronic acid（AAPBA） was synthesized and then examined as a new functional monomer for protein *** was allowed to be copolymerized with acrylamide to produce hemoglobin- or lysozyme-imprinted *** template rebinding tests,the imprinted gels showed significant increase in the specific binding with the increase of the AAPBA amounts in the prepolymerization *** results indicate that AAPBA may be a useful functional monomer for its moderate interactions with protein molecules.

关键词： Protein imprinting Hydrogels Hemoglobin Lysozyme 3-Aminophenylboronic acid

A QSRR Study on the Relative Retention Time of Halogenated Methyl-phenyl Ethers

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Chinese Journal of Structural Chemistry 2006年第7期25卷 811-817页

作者： XU Hui-Ying YU Qing-Sen ZOU Jian-Wei wang yan-hua wang Hong-Qing CHEN Xue-Song College of Biology ＆ Environment Engineering Zhejiang Shuren University Hangzhou 310015 China Key Laboratory for Molecular Design and Nutrition Engineering Ningbo Institute of Technology Zhejiang University Ningbo 315104 China

Halogenated methyl-phenyl ethers （anisoles） are ubiquitous organic compounds in the environment. In the present study, geometrical optimization and electrostatic potential calculations have been performed for 42 halogenated anisoles at the HF/6-31 G^＊ level. A number of statistically based parameters have been obtained. By multiple regression method, linear relationships between the gas-chromatographic relative retention time （RRT） and structural descriptors have been established for the training set of 32 halogenated anisoles. The result showed that the parameters derived from electrostatic potentials （ESPs） together with the molecular volume （Vmc） could be well used to express the quantitative structure-RRT relationships of halogenated anisoles. The best two-variable regression model gives a correlation coefficient of 0.980 and a standard deviation of 0.07, and the leave-one-out cross-validated correlation coefficient is 0.975. The goodness of the model has been further validated through exploring the predictive power for the testing set of 10 halogenated anisoles.

关键词： halogenated methyl-phenyl ethers (anisoles) molecular electrostatic potentials (ESPs) relative retention time (RRT) QSRR

Ab Initio Calculations on Halogen Bond Between N—Br and Electron-donating Groups

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Chemical Research in Chinese Universities 2007年第3期23卷 355-359页

作者： wang yan-hua CHEN Xue-song ZOU Jian-wei YU Qing-sen College of Biology and Environment Engineering Zhejiang Shuren University Hangzhou 310015P. R. China Key Laboratory for Molecular Design and Nutrition Engineering of Ningbo City Ningbo Institute of Technology Zhejiang University Ningbo 315100 P. R. China Department of Chemistry Zhejiang University Hangzhou 310027 P. R. China

Ab initio calculations of complexes formed between N-bromosuccinimide and a series of electron-donating groups were performed at the level of MP2/Lanl2DZ^＊ to gain a deeper insight into the nature of the N--Br halogen bonding. For the small complexes, H3 C--Br… NH3 and H2 N--Br…NH3 , the primary calculation has demonstrated that the N--Br in H2 N--Br… NH3 can form a much stronger halogen-bonding complex than the C--Br. A comparison of neutral hydrogen bond complex series reveals that the electron-donating capacities of the atoms decrease in the order, N 〉 O 〉 S; 0 （ sp^3 ）〉 0 （ sp^2 ）, which is adequate for the C--Br halogen bonding. Interaction energies, in conjunction with the geometrical parameters show that the affinitive capacity of trihalide anions X^-3 with N-bromosuccinimide are markedly lower than that of the corresponding X^- with N-bromosuccinimide, even lower than those of neutral molecules with N-bromosueeinimide. AIM analyses further eorffirmed the above results.

关键词： Halogen bond N-bromosuccinimide Ab initio AIM theory Interaction energy

Synthesis,Crystal Structure and Biological Activities of Novel Di-n-butyl Tin Di-carboxylate

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Chemical Research in Chinese Universities 2009年第6期25卷 851-855页

作者： wang yan-hua DU Da-feng ZHU Chao-guang DUXi-guang ZHU Dong-sheng Faculty of Chemistry Northeast Normal University Changchun 130024 P. R. China

A novel macrocyclic complex 2{[（n-Bu2Sn）4O2-L2]2DMF} was synthesized by the reaction of 4-（1,2- dithioethylene）methylene-3,5-disoxo-1,6-heptadiene-1,7-dis-（o-formy~）-dis-p-phenoxyacetic acid（LH2, compound 1） with di-n-butyltin oxide. Compound 1 and complex 2 were characterized by elemental analysis, FTIR spectroscopy, and ~H NMR spectroscopy. The crystal structure of complex 2 was determined by single crystal X-ray diffraction analysis. There are two crystallographic independent molecules in complex 2, and each molecule structure is centro-symmetric and features a central rhombus cyclic Bu4Sn2O2 unit with two exocyclic Sn atoms linked at the O atoms of the four-membered ring. In molecule A, the four Sn atoms are five-coordinated. However, in molecule B, the four Sn atoms have two different coordination geometries, the endocyclic Sn atoms are five-coordinated and the exocyclic Sn atoms are four-coordinated. The dicarboxylate ligands in molecules A and B bridge exocylic or endocyclic tin atoms, forming two macroheterocycles with 26 atoms. Pilot studies have indicated that complex 2 has good anti- bacterial and antitumour activities.

关键词： Organotin(IV) carboxylate Di-n-butyl tin di-carboxylate Di-n-butyl tin oxide Crystal structure Antibacterial activity Anti-tumour activity

Simulation of hard–soft material interaction under impact loading employing the material point method

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Science China(Technological Sciences) 2015年第4期58卷 763-768页

作者： LIU Han Tao JIANG Shan CHEN Zhen GAN Yong CHANG Jian Zhong wang yan hua TONG Zhi Hui Laboratory of Energy & Environment and Computational Fluid Dynamics North University of China Department of Civil and Environmental Engineering University of Missouri School of Aeronautics and Astronautics Zhejiang University

Understanding the mechanisms of hard–soft material interaction under impact loading is important not only in the defense industry but also in daily ***,traditional mesh-based spatial discretization methods that are time consuming owing to the need for frequent re-meshing,such as the finite element method and finite difference method,can hardly handle large deformation involving failure evolution in a multi-phase interaction *** objective of this research is to develop a quasi-meshless particle method based on the material point method for the model-based simulation of the hard–soft material interaction *** demonstrate the proposed procedure,scenarios of a hard–soft material impact test are considered,where a force is applied to layers of materials and a hard bar with an initial velocity impacts a target with layers of different *** stress wave propagation and resulting failure evolution are simulated and compared with available *** research tasks are then discussed on the basis of the preliminary results.

关键词： material point method hard--soft materials impact quasi-meshless particle method