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Virologica Sinica 2019年第6期34卷 712-721页

作者： Yan Wang Qingyun Cai Jiannan Chen Zhihong Huang Wenbi Wu meijin yuan Kai Yang State Key Laboratory of Biocontrol Sun Yat-sen University

Our previous study has shown that the Autographa californica multiple nucleopolyhedrovirus(AcMNPV) p48(ac103)gene is essential for the nuclear egress of nucleocapsids and the formation of occlusion-derived virions(ODVs). However,the exact role of p48 in the morphogenesis of ODVs remains unknown. In this study, we demonstrated that p48 was required for the efficient formation of intranuclear microvesicles. To further understand its functional role in intranuclear microvesicle formation, we characterized the distribution of the P48 protein, which was found to be associated with the nucleocapsid and envelope fractions of both budded virions and ODVs. In Ac MNPV-infected cells, P48 was predominantly localized to nucleocapsids in the virogenic stroma and the nucleocapsids enveloped in ODVs, with a limited but discernible distribution in the plasma membrane, nuclear envelope, intranuclear microvesicles, and ODV envelope. Furthermore,coimmunoprecipitation assays showed that among the viral proteins required for intranuclear microvesicle formation, P48 associated with Ac93 in the absence of viral infection.

关键词： P48 Baculovirus Intranuclear microvesicle formation Protein association Ac93

Introduction of temperature-sensitive helper and donor plasmids into Bac-to-Bac baculovirus expression systems

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Virologica Sinica 2015年第5期30卷 379-385页

作者： Zhihong Huang Ao Li Mengjia Pan Wenbi Wu meijin yuan Kai Yang State Key Laboratory of Biocontrol Sun Yat-sen University

In the baculovirus shuttle vector(bacmid) system, a helper plasmid and a donor plasmid are employed to insert heterologous genes into a cloned baculovirus genome via Tn7 transposition in Escherichia coli. The helper and donor plasmids are usually cotransfected with constructed bacmids into insect cells, which will lead to integration of these plasmids into the viral genome,and hence to the production of defective virions. In this study, to facilitate the preparation of plasmid-free recombinant bacmids, we modified a set of helper and donor plasmids by replacing their replication origins with that of a temperature-sensitive(ts) plasmid, p SIM6. Using the resulting ts helper plasmid p MON7124 ts and the ts donor plasmid p FB1ts-PH-GFP, a recombinant bacmid,b Ac WT-PG(-), was constructed, and the transposition efficiency was found to be 33.1%. The plasmids were then removed by culturing at 37 °C. For b Ac WT-PG(-), the infectious progeny virus titer and the protein expression level under the control of the polyhedrin promoter were similar to those of a bacmid constructed with unmodified helper and donor plasmids. These ts plasmids will be useful for obtaining plasmid-free bacmids for both heterologous protein production and fundamental studies of baculovirus biology.

关键词： baculovirus Bac-to-Bac baculovirus expression syst

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化疗巡视卡的设计与应用

护理研究（上旬版） 2009年第8期23卷 2044-2045页

作者：袁美锦河北北方学院附属第一医院

化疗是治疗肿瘤的重要手段之一,化疗药物外渗是化疗过程中比较常见的局部并发症。据报道,国内化疗外周渗漏率为0.1%－6.0%,国外报道为0.1%－6.5%。化疗药物外渗可导致局部皮肤及软组织非特异性炎症,临床上由于某些药物的强刺激性,外渗... 详细信息

化疗是治疗肿瘤的重要手段之一,化疗药物外渗是化疗过程中比较常见的局部并发症。据报道,国内化疗外周渗漏率为0.1%－6.0%,国外报道为0.1%－6.5%。化疗药物外渗可导致局部皮肤及软组织非特异性炎症,临床上由于某些药物的强刺激性,外渗处理后效果欠佳,有的出现组织坏死。甚至导致功能障碍。新的医疗事故处理条例规定,局部注射造成组织坏死,成人大于体表面积的2%可定为四级医疗事故。因此,预防化疗药物外渗比外渗后处理更为重要。我科为了减少病人化疗药物外渗的危险性,从2007年10月开始应用化疗药物巡视卡,效果较为满意。现报道如下。[第一段]

关键词：化疗过程巡视卡化疗药物外渗设计非特异性炎症医疗事故处理四级医疗事故组织坏死

苏云金芽孢杆菌的cry2A芽孢期启动子和分子伴侣ORF1-ORF2对Cry11Aa蛋白表达的影响

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微生物学报 2008年第5期48卷 672-676页

作者：师永霞曾少灵袁美妗孙钒庞义中山大学有害生物控制与资源利用国家重点实验室

【目的】分析苏云金芽孢杆菌的cry2A型芽孢期启动子对晶体蛋白Cry11Aa的协调作用和分子伴侣ORF1-ORF2对Cry11Aa表达的促进功能。【方法】3个包括cry11Aa编码区的重组质粒pHcy1、pHcy2和pHcy4被构建并电激转化到苏云金芽孢杆菌晶体缺陷株... 详细信息

【目的】分析苏云金芽孢杆菌的cry2A型芽孢期启动子对晶体蛋白Cry11Aa的协调作用和分子伴侣ORF1-ORF2对Cry11Aa表达的促进功能。【方法】3个包括cry11Aa编码区的重组质粒pHcy1、pHcy2和pHcy4被构建并电激转化到苏云金芽孢杆菌晶体缺陷株4Q7中,其中pHcy1质粒携带cry11Aa基因自身启动子和分子伴侣p19基因,pHcy2携带cry2A型芽孢期启动子和分子伴侣orf1-orf2基因,pHcy4质粒在pHcy1的上游插入了cry2A型芽孢期启动子和分子伴侣orf1-orf2基因。SDS-PAGE分析了Cry11Aa蛋白在各重组苏云金菌株中的表达情况,并通过生物测定确定了其对蚊虫的生物活性。【结果】SDS-PAGE结果表明,Cry11Aa蛋白在4Q7(pHcy1)和4Q7(pHcy4)均获得了表达,在4Q7(pHcy2)中未检测到Cry11Aa蛋白,推测晶体蛋白Cry11A不能利用cry2A型启动子进行表达调控;Cry11Aa蛋白在等体积4Q7(pHcy4)培养液中的表达量是4Q7(pHcy1)菌株的1.25倍,暗示着分子伴侣ORF1-ORF2在某种程度上能提高Cry11Aa的蛋白表达量。4Q7(pHcy1)和4Q7(pHcy4)形成的Cry11Aa蛋白晶体的形状和大小相似,两者对致倦库蚊的生物活性没有明显差异,LC50s分别为59.33ng/mL和66.21ng/mL。【结论】推测晶体蛋白Cry11A能否成功表达与其使用启动子的类型和两者的协调配合有关。分子伴侣ORF1-ORF2虽然在某种程度上能提高Cry11Aa的蛋白表达量,但对提高Cry11Aa蛋白的杀蚊毒力没有显著性帮助。

关键词：苏云金芽孢杆菌分子伴侣 p19基因 orf1-off2基因晶体蛋白Cry11Aa

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儿童与青少年心脏性猝死的病因和预防

心血管病学进展 2019年第6期40卷 935-938页

作者：刘颖袁美锦河北北方学院附属第一医院

儿童与青少年心脏性猝死(SCD)的研究尚处于发展阶段,SCD相关的症状多缺乏特异性,在致死性事件发作前,很多SCD患者并无临床症状,体格检查及静息心电图有可能正常,这使得辨别高危个体极为困难。因此,及早明确儿童与青少年猝死的病因及筛... 详细信息

儿童与青少年心脏性猝死(SCD)的研究尚处于发展阶段,SCD相关的症状多缺乏特异性,在致死性事件发作前,很多SCD患者并无临床症状,体格检查及静息心电图有可能正常,这使得辨别高危个体极为困难。因此,及早明确儿童与青少年猝死的病因及筛查辨识是目前儿科心血管领域的研究热点,现就儿童与青少年SCD的病因与筛查辨识方法进行综述。

关键词：心脏性猝死儿童青少年

杆状病毒AcMNPV p48基因在昆虫细胞中的表达

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微生物学报 2010年第4期50卷 465-471页

作者：袁美妗黄振球胡朝阳杨凯庞义中山大学有害生物控治与资源利用国家重点实验室广州510275

【目的】p48(ac103)基因在昆虫杆状病毒中高度保守,暗示其具有重要的生物学功能。为了研究该基因的功能,我们首先对该基因的表达特征进行描述。【方法】以杆状病毒代表种——苜蓿银纹夜蛾核型多角体病毒(Autographa californica multipl... 详细信息

【目的】p48(ac103)基因在昆虫杆状病毒中高度保守,暗示其具有重要的生物学功能。为了研究该基因的功能,我们首先对该基因的表达特征进行描述。【方法】以杆状病毒代表种——苜蓿银纹夜蛾核型多角体病毒(Autographa californica multiple nucleopolyhedrovirus,AcMNPV)的p48基因为研究对象,利用Bac-to-Bac杆状病毒表达载体系统分别构建了在P48蛋白N-端和C-端融合HA-标签,并且携带绿色荧光蛋白基因和多角体蛋白基因的重组Bacmid。将重组Bacmid转染Sf9细胞,收集含病毒的上清去感染Sf9细胞,在感染后不同时间点收集细胞进行SDS-PAGE电泳,利用商业化的HA抗体进行Western blot分析以检测融合蛋白在昆虫细胞中的表达情况。【结果】用C-端融合HA-标签的重组病毒感染细胞后12h即可检测到一条43kDa左右、能与HA抗体发生特异性结合的蛋白条带,该特异性蛋白的表达一直持续到病毒感染后96h。从感染后48h起一直到96h,均能检测到另外一条约26kDa的蛋白条带也能与HA抗体发生特异性结合。在N-端融合HA-标签的重组病毒感染的细胞中没有检测到与HA抗体特异结合的蛋白。【结论】结果表明,p48基因是个晚期基因,在病毒感染的晚期表达,并且该蛋白在昆虫细胞中表达时N-端可能被剪切。

关键词： AcMNPV p48基因表达剪切

Stabilities of delay stochastic McKean-Vlasov equations in the G-framework

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Science China(Information Sciences) 2025年第1期68卷 255-277页

作者： Haiyan yuan Quanxin ZHU Department of Mathematics Heilongjiang Institute of Technology Key Laboratory of Computing and Stochastic Mathematics (Ministry of Education) School of Mathematics and Statistics Hunan Normal University

This article focuses on a type of stochastic Mc Kean-Vlasov equation in the G-framework(G-SMVE) and addresses the stability issue for delay stochastic Mc Kean-Vlasov equations in the G-framework(G-SMVDEs). Distribution dependence and uncertainty prevent us from directly applying the stochastic analysis method for stochastic Mc Kean-Vlasov equations(SMVEs)to G-SMVEs directly. To overcome this difficulty, we introduce definitions, including the derivative of a function with a law under the G-expectation and the Lions derivatives. Then we construct a new G-It? formula for G-SMVEs according to the G-It? formula for stochastic differential equations in the G-framework(G-SDEs) and the It? formula for SMVEs. Using the new G-It? formula and the Lyapunov functional method, we investigate the moment exponential stability and almost sure asymptotic stability of G-SMVDEs. To overcome the difficulty in obtaining the distribution dependence of the exact solution to the G-SMVDE, we introduce the empirical measure and the corresponding interacting particle system, and then prove the stability equivalence between the underlying G-SMVDE and the corresponding interacting particle system. Two examples are used to confirm our theoretical results.

关键词： delay stochastic McKean-Vlasov equations Wasserstein distance G-Brownian motion Lions derivative stability

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杆状病毒对细胞凋亡的调节

中国生物防治 2000年第1期16卷 38-42页

作者：袁美妗吴文言龙綮新中山大学生物防治国家重点实验室广州510275

细胞凋亡是细胞的主动性死亡过程 ,它在生物体的发育、自身稳定中起重要作用。病毒感染是常见的诱导细胞凋亡的因素 ,而作为打破宿主防御体系的一种策略 ,许多病毒自身的基因组编码有抗细胞凋亡的基因。本文综述了杆状病毒及其一些基因... 详细信息

细胞凋亡是细胞的主动性死亡过程 ,它在生物体的发育、自身稳定中起重要作用。病毒感染是常见的诱导细胞凋亡的因素 ,而作为打破宿主防御体系的一种策略 ,许多病毒自身的基因组编码有抗细胞凋亡的基因。本文综述了杆状病毒及其一些基因产物对细胞凋亡的诱导与抑制作用。

关键词：杆状病毒细胞凋亡调节诱导抑制

Insect seedling herbivory is influenced by multiple factors,but the plant apparency theory is more supported than other hypotheses——A case study in a subtropical forest

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Forest Ecosystems 2025年第1期12卷 1-10页

作者： Baozhu yuan Bo Wang School of Resources and Environmental Engineering Anhui UniversityHefei230601China Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration(Anhui University) Hefei230601China Anhui Shengjin Lake Wetland Ecology National Long-term Scientific Research Base Dongzhi247230China

Insect herbivory is ubiquitous in various ecosystems,and directly influences the growth and survival of individual plants,especially during their vulnerable early life stages like the seedling ***,in turn,exerts a significant influence on forest community diversity and structure,as well as ecosystem function and *** variation in herbivory has been detected both among and within plant *** decades,many hypotheses have been proposed to explain such variations,including both biotic and abiotic ***,most studies have considered only one or several of these hypotheses by focusing on a few potential variables,and their results were usually inconsistent;thus,the factors driving herbivory remain *** this study,we examined leaf herbivory by insects of woody species seedlings in a subtropical forest in southwestern China over two *** total,24 potential variables that represented abiotic resource availability,characters of individual seedlings,conspecific and heterospecific species,and the whole seedling community were selected to test several commonly discussed alternative herbivory ***,our findings showed that the plant apparency hypothesis was more supported than the other hypotheses in explaining insect seedling *** results further indicated that the mechanisms and causes of insect herbivory are complex,multifactorial,species-specific and vary with seasons,indicating that there may be no uniform rules in explaining herbivory for all ***,such complexity may play an important role in promoting species coexistence and biodiversity maintenance in seedling communities,which may further translate into the following generation of saplings or even adult *** in the community of insect herbivores and/or variables influencing insect herbivory,may disrupt stability of the original seedling community,thus affecting the regeneration and development of the entire forest comm

关键词： Canopy openness Leaf size Plant animal interaction Plant apparency theory Seedling height Species richness

Numerical simulation of microstructure and microporosity morphology in directional solidification of aluminum-copper alloys:Effect of copper content and withdrawal rate

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China Foundry 2025年第1期22卷 33-44页

作者： Wei yuan Hai-dong Zhao Xu Shen Chun Zou yuan Liu Qing-yan Xu National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510640China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Tsinghua UniversityBeijing 100084China

Microporosity formed in the solidification process of Al alloys is detrimental to the alloy properties.A two-dimensional cellular automaton(CA)model was developed to simulate the microstructure and microporosity formation in Al-Cu alloys,considering variations in Cu content and solidification *** results indicate that the Cu content primarily influences the growth of *** validate the model,directional solidification experiments were conducted on Al-Cu alloys with varing Cu contents and withdrawal *** experimental results of dendrites and microporosity characteristics agree well with the predictions from the developed model,thus confirming the validity of the *** alloy’s liquidus temperature,dendrite morphology,and hydrogen saturation solubility arising from different Cu contents have significant effects on microporosity *** withdrawal rate primarily affects the nucleation of hydrogen microporosity by altering cooling rates and dendritic growth rates,resulting in different microporosity characteristics.

关键词： microporosity dendrites cellular automaton Al-Cu alloys directional solidification