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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第2期12卷 83-92页

作者： Chang-jun HUANG Tong zhang fang-fang LI Xin-yue zhang Xue-ping ZHOU State Key Laboratory of Rice Biology Institute of Biotechnology Zhejiang University Hangzhou 310029 China

Virus-induced gene silencing (VIGS) is a recently developed technique for characterizing the function of plant genes by gene transcript suppression and is increasingly used to generate transient loss-of-function assays. Here we report that the 2mDNA1, a geminivirus satellite vector, can induce efficient gene silencing in Nicotiana tabacum with Tobacco curly shoot virus. We have successfully silenced the β-glucuronidase (GUS) gene in GUS transgenic N. tabacum plants and the sulphur desaturase (Su) gene in five different N. tabacum cultivars. These pronounced and severe silencing phenotypes are persistent and ubiquitous. Once initiated in seedlings, the silencing phenotype lasted for the entire life span of the plants and silencing could be induced in a variety of tissues and organs including leaf, shoot, stem, root, and flower, and achieved at any growth stage. This system works well between 18-32°C. We also silenced the NtEDS1 gene and demonstrated that NtEDS1 is essential for N gene mediated resistance against Tobacco mosaic virus in N. tabacum. The above results indicate that this system has great potential as a versatile VIGS system for routine functional analysis of genes in N. tabacum.

关键词： Virus induced gene silencing Geminivirus Alphasatellite Nicotiana tabacum

Bis(7)-Tacrine, a Promising Anti-Alzheimer's Agent,Attenuates Glutamate-Induced Cell Injury in Primary Cultured Cerebrocortical Neurons of Rats

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Wuhan University Journal of Natural Sciences 2001年第3期6卷 737-741页

作者： zhang Bai fang,Peng fang fang,zhang Jiang zhou,Wu Dong cheng  Biochemistry Department, School of Medicine, Wuhan University, Wuhan 430071, China Biochemistry Department School of Medicine Wuhan University Wuhan China

The effects of bis(7) tacrine, a novel dimeric acetylcholinesterase (AChE) inhibitor, on glutamate induced cell injury were investigated in primary cerebral cortical neurons of rats. Exposure of cultured neurons (12 days after plating) to 0.5 mmol/L glutamate for 30 min resulted in significant cell damage. Pretreatment with bis(7) tacrine (0.03 1.0 μmol/L) reduced the glutamate induced neurotoxicity in a concentration dependent manner and the maximal response was seen at 1 μmol/L with approximately 30% protection. A receptor binding assay showed that bis(7) tacrine can completely displace MK 801 binding to rat cortical membrane with an IC 50 of 0.57 μmol/L. These findings suggest that bis(7) tacrine can directly interact with N methyl D aspartate receptor channel complex, which may contribute to the inhibitor's protective effects against glutamate induced excitotoxicity. Thus, it is possible that anti glutamate/anti AChE synergism is responsible for potentially better Alzheimer's therapy of bis(7) tacrine relative to tacrine.

关键词： bis(7) tacrine tacrine cholinesterase inhibitor glutamate primary neuronal cell culture

Protective effects of Radix Cynanchum bungei on ischemia-induced neuronal and cognitive impairment in mice

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中国药理学与毒理学杂志 2017年第5期31卷 464-465页

作者： CHEN Mei-hua CHEN Wei MA Jian zhang fang-fang ZHOU Yan-meng Institute of Pharmacology Taishan Medical College

OBJECTIVE To investigate the effects of Radix Cynanchum bungei extract(RCBE) on cerebral ischemia-reperfusion(I/R) and acute cerebral ischemia induced impairment in *** I/R model was induced by bilateral carotid artery occlusion(BCAO)-reperfusion method and Y-maze learning and memory performance was assessed after reperfusion. Na^+-K^+-ATPase,Ca^(2+)-ATPase and SOD activity,as well as MDA content in mouse brain tissue were measured. Numbers of mouth-opening breaths of the isolated mouse head were observed in acute cerebral ischemia *** Learning and memory ability in mice with RCBE were improved significantly compared with model group. The activity of SOD,Na^+-K^+-ATPase and Ca^(2+)-ATPase were increased,while MDA contents decreased after RCBE(0.5,1.0 and 2.0 g·kg^(-1)) and piracetam(0.5 g·kg^(-1)) treatment compared with the model group. RCBE at all concentrations significantly prolonged the number of mouth-opening breaths of the isolated mouse head. CONCLUSION RCBE preconditioning exerts a marked neuroprotective effect on the ischemia brain,which is related to improve the learning and memory via regulating energy metabolism and anti-oxidation.

关键词： Radix Cynanchum bungei cerebral ischemia-reperfusion acute cerebral ischemia neuroprotection

Involvement of cyclin dependent kinase 5 and its activator p35 in staurosporine-induced apoptosis of cortical neurons

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Acta Pharmacologica Sinica 2004年第9期 3-9页

作者： Bai-fang zhang, fang-fang PENG, Wen zhang, Han SHEN, Shao-bo WU, Dong-cheng WU Department of Biochemistry, Wuhan University School of Medicine, Wuhan 430071, China

AIM: To investigate whether cyclin-dependent kinase 5 and its regulatory protein p35 was involved in staurosporine-induced apoptosis of cortical neuronal cultures. METHODS: Primary cerebral cortical neurons were exposed to 300 nmol/L staurosporine. After incubation for different time, morphological alterations were observed with phase-contrast microscopy, fluorescence microscopy, and transmission electron microscopy. DNA fragmentation was detected by agarose gel electrophoresis. The protein levels of Cdk4, p53, Cdk5, and its regulatory protein p35 following staurosporine treatment were measured by Western blotting. The Cdk5 activity was assayed for histone H1 kinase activity by autoradiography. RESULTS: The typical morphological changes of apoptosis were observed and the nuclear DNA fragmentation showed the characteristic "ladder" pattern after the cells were treated by staurosporine. The Cdk5 protein level increased markedly at 3 h and continued to 24 h. The p35 level increased at 3 h after being expose

关键词： staurosporine primary cerebral cortical neurons apoptosis cyclin-dependent kinase 5 p35 protein protein p53

Regulation by phosphodiesterase of anxiety-and depressive-like behavior induced by alcohol withdrawal in mice

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中国药理学与毒理学杂志 2021年第9期35卷 667-668页

作者： LIU Xiao-qian WANG Dong ZHENG Wen-qing zhang fang-fang zhang Han-ting Institute of Pharmacology Shandong First Medi-cal University&Shandong Academy of SciencesTai’an 271016China Department of Pharma-cology Qingdao University School of PharmacyQingdao 266073China

OBJECTIVE Alcohol dependence is not only the most common public health prob⁃lem worldwide,but also the cause of many alco⁃hol-related diseases,such as anxiety and depres⁃***,the mechanism of these comor⁃bidities is not ***,the role of phos⁃phodiesterases(PDEs)in anxiety-and depres⁃sion-like behavior induced by alcohol withdrawal has received increasing *** are a superfamily of enzymes that catalyze the hydroly⁃sis of intracellular cyclic AMP(cAMP)and(or)cyclic GMP(cGMP).There are 11 families(PDE1-PDE11),each of which has 1 to 4 sub⁃types encoded by different *** the present study,we identified the key PDEs involved in anxiety-and depression-like behavior induced by alcohol *** After withdrawal from short-term or chronic intermittent ethanol vapor exposure(STEVE and CIEVE,respectively),adult male C57BL/6J(B6)mice were tested for anxiety-and depression-like behavior using the sucrose preference,open field,elevated plus-maze,tail suspension,forced swimming,hole board and light-dark *** addition,the expression of PDE subtypes(PDE2,PDE4,and PDE7)in the hippocampus,amygdala,and stria⁃tum,which are considered as anxiety-and(or)depression-related brain regions,was detected by Western ***①Differences in anxiety-and depression-like behaviors between STEVE and CIEVE *** to STEVE mice,CIEVE mice showed greater anxiety-and depression-like behavior in the tests described above.②The expression of PDE2,PDE4 and PDE7 in the anxiety-and depression-related brain regions of CIEVE *** to the STEVE mice,CIEVE mice showed significant higher expression of PDE4A and PDE7A in the hippo⁃campus(P<0.05)and PDE4D and PDE7A in the amygdala(P<0.05).However,the expres⁃sion of PDE2A,PDE4B,PDE4D and PDE7B in the hippocampus,PDE2A,PDE4A,PDE4B and PDE7B in the amygdala,PDE2A,PDE4A,PDE4B,PDE4D,PDE7A and PDE7B in the striatum was not significantly *** The model of CIEVE showed significant anxiety-and

关键词： phosphodiesterases alcohol with⁃drawal behavior

Persuasive and Politeness Strategies in Chinese Foreign Trade

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海外英语 2013年第1X期 258-260页

作者： zhang fang-fang Foreigh Language School East China University of Science and Technology

During international trade negotiations Chinese salespersons tend to employ a variety of persuasive and politeness strat egies in marketing their *** involves face-threatening acts (FTAs),thus politeness strategies which are applied to reduce face-threatening are combined with persuasive *** paper,taking Brown and Levinson's model of po liteness as a reference,makes an analysis on politeness strategies used in persuasive communication of the salespersons.

关键词： FTAs positive politeness strategies negative polit

Observability for the Schr?dinger equation in a uniform magnetic field

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Acta Mathematica Sinica,English Series 2025年

作者： zhang fang Department of Mathematics Beijing Institute of Technology

We prove the observability inequalities at two time points for the Schr?dinger equation in a uniform magnetic field in dimensions 2 and 3. The proofs mainly rely on Nazarov’s uncertainty principle. In particular, the observability inequality in three dimensions can also be derived from the approach used to establish the Amerin-Berthier uncertainty principle.

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The characteristics of atmospheric CO_2 concentration variation of four national background stations in China

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Science China Earth Sciences 2009年第11期52卷 1857-1863页

作者： LIU LiXin, ZHOU LingXi, zhang XiaoChun, WEN Min, zhang fang, YAO Bo & fang ShuangXi Key Laboratory for Atmospheric Chemistry, Centre for Atmosphere Watch and Services (CAWAS), Chinese Academy of Meteoro- logical Sciences (CAMS), China Meteorological Administration (CMA), Beijing 100081, China Key Laboratory for Atmospheric Chemistry Centre for Atmosphere Watch and Services (CAWAS) Chinese Academy of Meteorological Sciences (CAMS) China Meteorological Administration (CMA) Beijing China

Atmospheric carbon dioxide is an important kind of greenhouse gas which influences global temperature. Its concentration variation could indicate the distribution of human and natural activities in various regions. Through the non-dispersive infrared method, flask sampling of atmospheric CO2 concen- tration was measured weekly at four national background stations including Waliguan, Shangdianzi, Lin’an, and Longfengshan. Based on the data collected from September 2006 to August 2007, along with the Waliguan station’s experience on in situ observational data processing, the selection methods for sampling data through the atmospheric background CO2 concentration analysis were preliminarily discussed. On the basis of this result, the variation features of the four typical regions’ atmospheric background CO2 concentration was analyzed for the first time. The results show that the atmospheric CO2 concentration at Waliguan, Shangdianzi, Lin’an, and Longfengshan is 383.5, 385.9, 387.8, and 384.3 ppm, respectively. During the research period, CO2 concentration at the Waliguan station changed slightly. However, the CO2 concentration changed sharply at the Shangdianzi and the Lin’an stations due to the great influence of human activities in the Jingjinji and the Changjiang Delta economic zones, and changed regularly with seasons at Longfengshan station under dual influences of human activities and plant photosynthesis. The results from this study can lay the foundation for more profound studies on atmospheric CO2 concentration level of different areas in China, and could be used to improve the understanding of carbon source and sink distribution.

关键词： atmospheric CO2 flask sampling background data selection CO2 concentration regional difference

Reconstruction characteristics of gut microbiota from patients with type 1 diabetes affect the phenotypic reproducibility of glucose metabolism in mice

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Science China Life Sciences 2025年第1期68卷 176-188页

作者： Zhiyi Wang Mengxue Gong Yuanyuan fang Huijuan Yuan Chenhong zhang State Key Laboratory of Microbial Metabolism School of Life Sciences and BiotechnologyShanghai Jiao Tong University Department of Endocrinology Henan Provincial People's HospitalPeople's Hospital of Zhengzhou University

The human microbiota-associated(HMA) mice model, especially the germ-free(GF)-humanized mice, has been widely used to probe the causal relationships between gut microbiota and human diseases such as type 1 diabetes(T1D). However, most studies have not clarified the extent to which the reconstruction of the human donor microbiota in recipient mice correlates with corresponding phenotypic reproducibility. In this study, we transplanted fecal microbiota from five patients with T1D and four healthy people into GF mice, and microbiota from each donor were transplanted into 10 mice. Mice with similar microbiota structure to the donor exhibited better phenotypic reproducibility. The characteristics of the microbial community assembly of donors also influenced the phenotypic reproducibility in mice, and individuals with a higher proportion of stochastic processes showed more severe disorders. Microbes enriched in patients with T1D had a stronger colonization potential in mice with impaired glucose metabolism, and microbiota functional features related to T1D were better reproduced in these mice. This indicates that assembly traits and colonization efficacy of microbiota influence phenotypic reproducibility in GF-humanized mice. Our findings provide important insights for using HMA mice models to explore links between gut microbiota and human diseases.

关键词： gut microbiome human microbiota-associated animal model type 1 diabetes

Isobaric enzymatic assays reveal depth-dependent variation in microbial ectoenzyme activities in the deepest ocean on Earth

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Science China Earth Sciences 2025年第1期68卷 185-194页

作者： Junwei CAO Jiahua WANG Hongge zhang Junhao DENG Binbin PAN Jiawang CHEN Li zhang Jiasong fang College of Oceanography and Ecological Science Shanghai Ocean University Ocean College Zhejiang University Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and Technology

Microbial ectoenzymes play essential roles in the transformation and mineralization of organic matter in the ***, conventional methods for measuring microbial ectoenzyme activities(MEAs) in the deep ocean under atmospheric conditions can misrepresent the metabolic activities of indigenous microbial communities. To overcome this limitation, we measured the activities of three microbial ectoenzymes(aminopeptidase, α-glucosidase, and β-glucosidase) under both atmospheric and in situ pressure conditions in seawater collected using pressure-retaining and non-pressure-retaining samplers in the Challenger Deep, Mariana Trench. In the case of aminopeptidase and α-glucosidase, the highest isobaric MEAs were observed in the surface layer(50 m), followed by those at abyssopelagic depths(4,000–6,000 m) for aminopeptidase, hadal realm(10,903 m)for α-glucosidase, while β-glucosidase activity exhibited the highest value at 10,903 m. Furthermore, the isobaric MEAs in hadal waters were commonly found to be higher than the decompressed counterparts, highlighting the importance of pressure-retaining sampling and isobaric enzymatic assays. The half-saturation constant(Km) showed a general decreasing trend with depth,suggesting that the deep ocean microbes might have adapted to the high-pressure and oligotrophic environment by increasing their ectoenzyme's affinity to substrate. Furthermore, particle-free MEAs contribute more to the total MEAs in the deep ocean than particle-associated MEAs, suggesting the significance of cell-associated and dissolved ectoenzymes in ocean *** study provides a foundation for future investigations of MEAs in the ocean and has important implications for understanding the dynamics of microbially mediated biogeochemical cycling in marine ecosystems.

关键词： Pressure-retaining sampling Microbial ectoenzyme activity Deep-sea microbes High pressure Mariana Trench