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Cross-linked Polyethylenimine as Potential DNA Vector for Gene Delivery with High Efficiency and Low Cytotoxicity

Acta Biochimica et Biophysica Sinica 2006年第11期38卷 780-787页

作者： Wei DONG~(1,2) Guang-Hui JIN~1 Shu-Feng LI~(1,3) Qi-Ming SUN~1 Ding-Yuan MA~1 Zi-Chun HUA~1 1 State Key Laboratory of Pharmaceutical biotechnology,college of Life Science,Nanjing university,Nanjing 210093,china 2 School of Chemical Engineering Nanjing university of Science and Technology,Nanjing 210094,china 3 college of Basic Medical Science,Southeast university,Nanjing 210009,china State Key Laboratory of Pharmaceutical biotechnology College of Life Science Nanjing UniversityNanjing 210093 China School of Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094 China college of Basic Medical Science Southeast UniversityNanjing 210009 China

Polyethylenimine (PEI) has been known as an efficient gene carrier with the highest cationiccharge *** transfection efficiency of PEI,along with its cytotoxicity,strongly depends on itsmolecular *** enhance its gene delivery efficiency and minimize cytotoxicity,we have synthesizedsmall cross-linked PEI with biodegradable linkages and evaluated their transfection efficiencies in *** study,branched PEI with a molecular weight of 800 Da was cross-linked by small diacrylate[1,4-butanediol diacrylate or ethyleneglycol dimethacrylate (EGDMA)] for 2-6 *** efficiencies of thecross-linked PEI in in vitro transfection of plasmid DNA containing enhanced green fluorescent protein(EGFP) reporter gene were assessed in melanoma B 16F10 cell line and other cell *** cytometrywas used to quantify the cellular entry efficiency of plasmid and the transgene expression *** of the cross-linked PEI in these cells were evaluated by MTT ***-PEI 800-4h,atypical cross-linked PEI reported here,mediated a more efficient expression of reporter gene than thecommercially available 25-kDa branched PEI control,and resulted in a 9-fold increase in gene deliveryin B16F10 cells and a 16-fold increase in 293T cells,while no cytotoxicity was found at the optimizedcondition for gene ***,the transfection activity of polyplexes was preserved in thepresence of serum proteins.

关键词： polyethylenimine gene delivery cytotoxicity B16F10 293T cell line

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Phylogenetic placement of Cynomorium in Rosales inferred from sequences of the inverted repeat region of the chloroplast genome

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Journal of Systematics and Evolution 2009年第4期47卷 297-304页

作者： ~(1,2)Zhi-Hong ZHANG ~3Chun-Qi LI ~2Jianhua LI~* 1(School of Life Sciences,Sun Yat-sen university,Guangzhou 510275,china) 2(Arnold Arboretum of Harvard university,Cambridge,MA 02138,USA) 3(college of Life Sciences,Henan agricultural university,Zhengzhou 450002,china) (School of Life Sciences Sun Yat-sen University Guangzhou 510275 China) (Arnold Arboretum of Harvard university Cambridge MA 02138 USA) (college of Life Sciences Henan Agricultural University Zhengzhou 450002 China)

Cynomorium is a herbaceous holoparasite that has been placed in Santalales,Saxifragales,Myrtales, or *** inverted repeat(IR)region of the chloroplast genome region is slow evolving and,unlike mitochondrial genes,the chloroplast genome experiences few horizontal gene transfers between the host and parasite. Thus,in the present study,we used sequences of the IR region to test the phylogenetic placements of Cynomorium. Phylogenetic analyses of the chloroplast IR sequences generated largely congruent ordinal relationships with those from previous studies of angiosperm phylogeny based on single or multiple *** was closely related to Caryophyllales and *** formed a clade where Peridiscus was sister to the remainder of the order, whereas Paeonia was sister to the woody clade of *** is not closely related to Santalales, Saxifragales,Myrtales,or Sapindales;instead,it is included in Rosales and sister to *** various placements of the holoparasite on the basis of different regions of the mitochondrial genome may indicate the heterogeneous nature of the genome in the ***,it is unlikely that the placement of Cynomorium in Rosales is the result of chloroplast gene transfer because Cynomorium does not parasitize on rosaceous plants and there is no chloroplast gene transfer between Cynomorium and Nitraria,a confirmed host of Cynomorium and a member of Sapindales.

关键词： Bayesian analyses chloroplast inverted repeat Cynomorium holoparasite maximum likelihood parsimony Rosales.

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Expression pattern and core region analysis of AtMPK3 promoter in response to environmental stresses

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Science china(Life Sciences) 2010年第11期53卷 1315-1321页

作者： GAO Fei1,2, SU Qi1, FAN YunLiu1& WANG Lei1 1biotechnology Research Institute/National Key Facility for Crop Gene Resources and Genetic Improvement, Chinese Academy of agricultural Science, Beijing 100081, china 2college of Life and Environmental Sciences, Minzu university of china, Beijing 100081, china biotechnology Research Institute/National Key Facility for Crop Gene Resources and Genetic Improvement Chinese Academy of Agricultural Science Beijing China college of Life and Environmental Sciences Minzu University of China Beijing China

The protein kinase AtMPK3,a component of the MAP kinase cascade,plays an important role in stress signal transduction in plant cells. To clarify how AtMPK3 is regulated at the transcriptional level in response to various environmental factors, the 1016-bp promoter sequence upstream of the transcription start site of the AtMPK3 gene was isolated. Analyses of the promoter sequence using plant promoter databases revealed that the AtMPK3 promoter contains many potential cis-acting elements involved in environmental stress responses. We constructed four deletion mutants of the AtMPK3 promoter, and introduced the intact and truncated promoter sequences fused to the β-glucuronidase (GUS) gene into Arabidopsis. GUS histochemical staining and quantitative fluorometric GUS assays were performed to visualize and compare the expression patterns in response to different environmental stimuli. The region between-188 and-62 upstream of the transcription start site was identified as the essential DNA sequence of the AtMPK3 promoter for responses to drought, high salinity, low temperature, and wounding. These results advance our understanding of the molecular mechanisms controlling AtMPK3 expression in response to different environmental stimuli.

关键词： Arabidopsis thaliana AtMPK3 promoter stress

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Ability of Agrogyron elongatum to accumulate the single metal of cadmium, copper, nickel and lead and root exudation of organic acids

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Journal of Environmental Sciences 2001年第3期13卷 368-375页

作者： YANG Hong 1, Jongathan W.C.Wong 2, YANG Zhi min\+1, ZHOU Li xiang 1(1. college of Science, Nanjing agricultural university, Nanjing\ 210095, china. 2. Department of Biology, Hong Kong Baptist university, china) 南京农业大学江苏南京 210095 香港浸会大学香港

Agrogyron elongatum were grown in nutrient solution containing moderate to high amounts of separate heavy metal of Cd, Cu, Ni and Ph in a greenhouse for a 9 - day. Cd, Cu, Ni and Ph generally led to decrease in the elongation of roots although the length of seedlings exposed to Cd and Ph at 0.05 and 0.5 mg/L showed to be slightly greater than that of controls. Of the four metals in the experiment, Ph was absorbed and accumulated to the highest level, with the concentrations of 92754 mg/kg dry weight (DW) in roots and 11683 mg/kg DW in shoots. Cd was moderately accumulated in Agrogyron elongatum, but the maximum bioaccumulation coefficients (BCs) for roots and shoots were observed. The patterns for Cu and Ni uptake and distribution in plants differed from those of Ph and Cd, as it was showed that the shoot accumulation of Cu and Ni was significantly higher than in roots. A. elongation had the highest Ni concentration in shoots (30261 mg/kg DW) at the external concentration of 250 mg/L. Cu ranked second, with a shoot concentration of 12230 mg/kg DW when 50 mg/L Cu in solution was applied. For the four trace elements tested, the highest concentrations in shoots decreased by the order of Ni > Cu > Ph > Cd (mg/kg DW), and those in roots were Ph > Cd > Ni > Cu (mg/kg DW). Malic, oxalic and citric acids exuded by roots exposed to 1 and 50 mg/L of the metals were detected. Release of organic acids from plants significantly differed among the metal treatments. Cu was most effectively in inducing root exudation of the three types of organic acids. Cd, and Ni were also the inducers of secretion of malic and oxalic acids. With reference of Pb, a small amounts of malic and oxalic acids were detected in the root exudates, but few quantities, of citric acid were. found. However, no correlation between alternations in root exudation of organic acids and metal accumulation could be established.

关键词： heavy metal organic acid Agrogyron elongation hyperaccumulation

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Facile Synthesis of Nanocrystalline Cr_2O_3 Thin Film

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Journal of Wuhan university of Technology(Materials Science) 2011年第6期26卷 1032-1035页

作者：杨明 School of Transportation Southeast University

A novel and facile synthesis route for the manufacture of transparent and uniform self-assembled nanocrystalline Cr2O3 （nc-Cr2O3） thin films with different morphology was reported, utilizing chromium nitrate as the inorganic source and triblock copolymer F127 as the morphology-directing agent by the evaporation-induced assembly （EIA） method. X-ray powder diffraction （XRD）, thermogravimetry-differential scanning calorimetry （TG-DSC）, N2-sorption, scanning electron microscopy （SEM） and transmission electron microscopy （TEM） were used to characterize the as-prepared nc-Cr2O3 thin films. The Cr2O3 thin film with different morphology was obtained by changing the relative humidity. The possible formation mechanism of the nc-Cr2O3 thin films with different morphologies was discussed.

关键词： microstrucmre Cr2O3 thin film

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The Preliminary Rearch on Plant Family Retrieval System of Angiosperm in inner mongolia

The Preliminary Rearch on Plant Family Retrieval System of A...

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2011 IEEE International Conference on Computer Science and Automation Engineering(CSAE 2011)

作者： Wang Shusen Luo Yuyang* Tan Hu She Hongyan Ecological and Environmental Sciences college inner mongolia agricultural university huhhot inner mongolia PRC.

For realizing electronic plant family retrieval of Angiosperm in inner mongolia, taking 10 plant families as example, we developed a Plant Family Retrieval System based on SILK software and the a series of books of Flora of inner mongolia. Using different plant characters of a specimen in any order, this system can search correct plant family that include this species.

关键词： Angiosperm in inner mongolia Family Retrieval System

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北方农牧交错带土壤风蚀沙化影响因子的风洞试验研究

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水土保持学报 2004年第3期18卷 1-4,8页

作者：何文清高旺盛妥德宝赵沛义中国农业大学农学与生物技术学院北京100094 内蒙古农业科学院内蒙古呼和浩特010018

土壤风蚀沙化是北方农牧交错带农牧业生产与发展的主要限制因子,通过室内风洞实验研究,定量分析了土壤风蚀率(风蚀强度)与风速及土壤水分的相关关系、土壤风蚀输沙量的空间分布规律以及翻耕后土壤风蚀的动态变化。结果表明:风蚀率与风... 详细信息

土壤风蚀沙化是北方农牧交错带农牧业生产与发展的主要限制因子,通过室内风洞实验研究,定量分析了土壤风蚀率(风蚀强度)与风速及土壤水分的相关关系、土壤风蚀输沙量的空间分布规律以及翻耕后土壤风蚀的动态变化。结果表明:风蚀率与风速变化成正相关,随着风速增大,风蚀率相应增加,18m/s风速是风蚀由轻变重的一个转折点;土壤水分与风蚀率呈负相关,水分含量越高,风蚀率越小,6%含水量水平是土壤风蚀由重变轻的一个转折点。通过曲线拟合表明,风蚀率与风速成幂函数的关系,与土壤水分含量成对数函数关系。土壤风蚀空间不同高度输沙量呈单峰曲线的变化趋势,在距地面2～4cm范围内集沙量最多,80%左右的沙量集中在近地面10cm范围内。土地翻耕是加重土壤风蚀的重要因素,对于天然草场,翻耕后风蚀强度是未翻耕的66～306倍,对于旱作农田,留茬覆盖可以有效控制土壤风蚀,翻耕马铃薯地风蚀强度是留茬地的25～108倍。

关键词：北方地区农牧交错带土壤风蚀沙化影响因子风洞试验

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Purification and characterization of keratinase from a new Bacillus subtilis strain

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Journal of Zhejiang university-Science B(Biomedicine & biotechnology) 2008年第9期9卷 713-720页

作者： Cheng-gang CAI1,2, Ji-shuang CHEN3, Jiong-jiong QI2, Yun YIN2, Xiao-dong ZHENG2 (1college of Biology and Environmental Engineering, Zhejiang Shuren university, Hangzhou 310015, china) (2college of Food Science and Biosystem Engineering, Zhejiang university, Hangzhou 310029, china) (3Institute of bioengineering, Zhejiang Sci-Tech university, Hongzhou 310018, china) college of Biology and Environmental Engineering Zhejiang Shuren University Hangzhou 310015 China.

The aim of this study was to purify and characterize a keratinase produced by a new isolated Bacillus subtilis KD-N2 strain. The keratinase produced by the isolate was purified using ammonium sulphate precipitation, Sephadex G-75 and DEAE (diethylaminoethyl)-Sepharose chromatographic techniques. The purified enzyme was shown to have a molecular mass of 30.5 kDa, as determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis. The optimum pH at 50 °C was 8.5 and the optimum temperature at pH 8.5 was 55 °C. The keratinase was partially inactivated by some metal ions, organic solvents and serine protease inhibitor phenylmethanesulfonyl fluoride (PMSF). Sodium dodecyl sulfate (SDS) and ethylene diamine tetraacetic acid (EDTA) had positive effect on the keratinase activity. Reducing agents including dithiothreitol (DTT), mercaptoethanol, L-cysteine, sodium sulphite, as well as chemicals of SDS, ammonium sulfamate and dimethylsulfoxide (DMSO) stimulated the enzyme activity upon a feather meal substrate. Besides feather keratin, the enzyme is active upon the soluble proteins ovalbumin, bovine serum albumin (BSA), casein and insoluble ones as sheep wool and human hair. Calf hair, silk and collagen could not be hydrolyzed by the keratinase.

关键词： Ammonium sulfatate Bacillus subtilis Characterization Feather Keratin Keratinase Purification Reducing agents

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Damage detection based on the propagation of longitudinal guided wave in a bimetal composite pipe

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Theoretical & Applied Mechanics Letters 2011年第2期1卷 20-24页

作者： Huixing Yun~(1,a) and Weiwei Zhang~2 1.college of Engineering Shanxi agricultural university,Taigu 030801,china 2.college of Science & Engineering,Jinan university,Guangzhou,china college of Engineering Shanxi agricultural university Taigu 030801 China college of Science & Engineering Jinan University Guangzhou China

This paper investigates the damage detection based on the propagation of guided wave in bimetal composite pipes,which can identify damage locations in both axial and circumferential *** feasibility of the method is showed by numerical simulations using FEM code ANSYS. Mode analysis is used to evaluate the guided wave mode and its structure,which can provide the basis of the mode selection in measurements *** guided wave propagation in a damaged pipe is computed by transient analysis.16 nodes around the pipe wall,as probes,are used to record the guided wave *** Pseudo Margenau-Hill distribution(PMHD)for each signal is carried out, three types of modes could be found,which are led mode,excited mode and lag mode in sequences. Based on the results,the arrival time of the excited mode could be used to locate damage in axial direction,and the energy distribution around the pipe of lag mode is consistent with the damage in circumferential *** simulation illustrated the possibility of detecting damage location in both axial and circumferential directions based on longitudinal ultrasonic guided waves only.

关键词： damage detection crack PMHD pipe

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Genotypic Differences in Grain Yield and Physiological Nitrogen Use Efficiency Among Rice Cultivars

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Pedosphere 2009年第6期19卷 681-691页

作者： ZHANG Ya-Li, FAN Jian-Bo, WANG Dong-Sheng and SHEN Qi-Rong2college of Resources and Environmental Sciences, Nanjing agricultural university, Nanjing 210095 (china) college of Resources and Environmental Sciences Nanjing Agricultural University Nanjing 210095 (China)

Efficient use of N in agricultural practice can increase yield, decrease production costs and reduce the risk of environmental pollution. Effects of N fertilizer application rates on grain yield and physiological N use efficiency (PE) in relation to the accumulation and redistribution of biomass and N in rice (Oryza sativa L.) cultivars were studied at two experimental farms of Nanjing agricultural university, Nanjing, china in 2004. Three high N use efficiency (NUE) rice cultivars (Wuyunjing 7, Nanguang and 4007) and one low NUE rice cultivar (Elio) with similar growth patterns were studied under seven N rates (0, 60, 120, 180, 240, 300 and 360 kg ha -1 ). Grain yield increased with the N application rate and attained plateau at 180 kg N ha -1 for rice cultivars at each site. Increasing N rate decreased PE for biomass and grain yield. Grain yield and PE of Elio were about 20% and 18% lower than those of high NUE cultivars. Differences in biomass, N accumulation and N redistribution were observed at the post-heading stage among rice cultivars with differing NUEs. The less reproductive tillers of Elio resulted in less demand for C and N during grain filling, thus leading to lower PE of Elio compared with the high NUE rice cultivars.

关键词：氮素利用效率水稻品种粮食产量品种间基因型差异生理南京农业大学氮肥施用量

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