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Aluminium Uptake and Accumulation in the Hyperaccumulator Camellia Oleifera Abel

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Pedosphere 2011年第3期21卷 358-364页

作者： ZENG Qi-Long chen rong-fu ZHAO Xue-Qiang WANG Huo-Yan SHEN Ren-Fang Sciences Nanjing 210008 (China) Graduate University of Chinese Academy of Sciences Beijing 100049 (China)

Oiltea camellia （Camellia oleifera Abel.）, an aluminium （Al） hyperaccumulator, grows well on acid soils in tropical or subtropical areas. In this study, the growth of oiltea camellia in response to Al application and the characteristics of Al uptake and accumulation were investigated using laboratory and field experiments. The growth of oiltea camellia seedlings in the nutrient solution tended to be stimulated by addition of Al. Results of the field experiment showed that oiltea camellia accumulated 11 000 mg kg-1 Al in leaves within 10 months, and the average rate of Al accumulation in new leaves was about 1100 mg kg-1 month-1; however, the monthly rate varied and was highest in spring and autumn. The results of the laboratory experiment on Al uptake by oiltea camellia seedlings in CaC12 solutions with various forms of Al showed that large amounts of Al supplied as Al3＋ and Al complexes Al-malate （1：1） and Al-F （1：1） were infiuxed into oiltea camellia roots, whereas Al supplied as Al-citrate （1：1）, Al-F （1：6）, Al-oxalate （1：3）, and Al-oxalate （1：1） complexes exhibited low affinity to oiltea camellia roots. The kinetics of Al3＋ cumulative uptake in excised roots and intact plants showed a biphasic pattern, with an initial rapid phase followed by a slow phase. The Al cumulative uptake was unaffected by low temperature, which indicated that Al uptake in oiltea camellia was a passive process. The efficient influx of Al into the roots and the high transport rate in specific seasons were presumed to account for the plentiful Al accumulation in leaves of oiltea camellia.

关键词： Al3+ Al complexes Al influx cumulative uptake oiltea camellia

Histone deacetylase inhibitor, 2-propylpentanoic acid, increases the chemosensitivity and radiosensitivity of human glioma cell lines in vitro

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Chinese Medical Journal 2012年第24期125卷 4338-4343页

作者： SHAO Cui-jie WU Ming-wei chen fu-rong LI Cong XIAYun-fei chen Zhong-ping State Key Laboratory of Oncology in South China Cancer Center of Sun Yat-sen University Guangzhou Guangdong 510060 China Department of Neurosurgery/Neuro-oncology Cancer Center of Sun Yat-sen University Guangzhou Guangdong 510060 China Department of Radiation Oncology Cancer Center of Sun Yat-sen University Guangzhou Guangdong 510060 China

Background Treatment for malignant glioma generally consists of cytoreductive surgery followed by radiotherapy and chemotherapy. In this study, we intended to investigate the effects of 2-propylpentanoic acid （VPA）, a histone deacetylase inhibitor, on chemosensitivity and radiosensitivity in human glioma cell lines. Methods Human glioma cell lines, T98-G, and SF295, were treated with temozolomide （TMZ） or irradiation （IR）, with or without VPA （1.0 mmol/L）. Then, cytotoxicity and clonogenic survival assay was performed. Cell cycle stage, apoptosis, and autophagy were also detected using flow cytometry and dansyl monocadaverin （MDC） incorporation assay. One-way analysis of variance （ANOVA） and t-test were used to analyze the differences among variant groups. Results Mild cytotoxicity of VPA was revealed in both cell lines, T98-G and SF295, with the 50% inhibiting concentration （IC50） value of （3.85±0.58） mmol/L and （2.15±0.38） mmol/L, respectively; while the IC50 value of TMZ was （0.20±0.09） mmol/L for T98-G and （0.08＋0.02） mmol/L for SF295. Moreover, if combined with VPA （1.0 mmol/L） for 96 hours, the sensitivity of glioma cells to TMZ was significant increased （P 〈0.05）. The surviving fractions at 2 Gy （SF2） of T98-G and SF295 cells exposed to IR alone were 0.52 and 0.58. However, when VPA was combined with IR, the SF2 of T98-G and SF295 dropped to 0.39 （P=0.047） and 0.49 （P=0.049）, respectively. Treatment with VPA plus TMZ or IR also resulted in a significant decrease in the proportion of cells in the G2 phase and increased apoptotic rates as well as autophagy in T98-G and SF295 cell lines （P 〈0.01）. Conclusion VPA may enhance the activities of TMZ and IR on glioma cells possibly through cell cycle block and promote autophagy, and thus could be a potential sensitizer of glioma treatment.

关键词： 2-propylpentanoic acid radiosensitivity glioma cell line

Glioblastoma stem cells resistant to temozolomide-induced autophagy

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Chinese Medical Journal 2009年第11期122卷 1255-1259页

作者： fu Jun LIU Zhi-gang LIU Xiao-mei chen fu-rong SHI Hong-liu PANG Jesse Chung-sean NG Ho-keung chen Zhong-ping State Key Laboratory for Cancer Research in Southern China and Department of Neurosurgery/Neuro-oncology Cancer Center Sun Yat-sen University Guangzhon Guangdong 510060 China Department of Anatomical & Cellular Pathology Chinese University of Hong Kong Shatin N.T. Hong Kong China

Background Recent studies have demonstrated the existence of a small fraction of cells with features of primitive neural progenitor cells and tumor-initiating function in brain tumors. These cells might represent primary therapeutic target for complete eradication of the tumors. This study aimed to determine the resistant phenotype of glioblastoma stem cells （GSCs） to temozolomide （TMZ） and to explore the possible molecular mechanisms underlying TMZ resistance. Methods Freshly resected glioblastoma specimen was collected and magnetic isolation of GSCs was carried out using the Miltenyi Biotec CD133 Cell Isolation kit. The cytotoxic effect of TMZ on CD133^＋ and CD133^- glioblastoma cells was determined by using the 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide （MTT） assay. Autophagy-related proteins （Beclin-1, LC3 and Atg5） and cleaved caspase-3 （p17） were analyzed by Western blotting. Immunofluorescent staining was used to detect Atg5, glial fibrillary acidic protein （GFAP） and CD133 expression in glioblastoma cells. Statistical analysis was carried out using SPSS 10.0 software. For all tests, the level of statistical significance was set at P 〈0.05. Results CD133^＋ glioblastoma ceils exhibited neurosphere-like growth in vitro and high expression of CD133 stem cell marker. The growth-inhibiting rate in CD133- glioblastoma cells treated with 5 or 50 pmol/L TMZ was significantly higher than that in CD133^＋ glioblastoma cells （（14.36±3.75）% vs （2.54±1.36）% or （25.95±5.25）% vs （2.72±1.84）%, respectively, P 〈0.05）. Atg5, LC3-11 and Beclin-1 levels were significantly lower in CD133^＋ glioblastoma cells than those in autologous CD133^- cells after TMZ treatment （P 〈0.05）. Caspase-3 was mildly activated only in CD133^- glioblastoma cells after exposure to TMZ （P 〈0.05）. Immunofluorescent staining revealed elevated expression of Atg5 in GFAP^＋ cells following TMZ treatment. Conclusions The GSCs display strong capability of tumor＇s resistance to TMZ. This resis

关键词： glioblastoma neoplastic stem cells chemoresistance temozolomide

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论新时代全面从严治党的内在属性

河北学刊 2019年第3期39卷 26-32页

作者：陈富荣甘肃省社会科学院甘肃兰州730070

中共十八大以来,习近平就如何管党治党、全面从严治党发表了一系列重要讲话和重要论述,系统地回答了新时代加强党的建设的重大理论和现实问题,形成了新时代全面从严治党的科学理论体系。总体看来,科学性与整体性相统一、时代性与战略性... 详细信息

中共十八大以来,习近平就如何管党治党、全面从严治党发表了一系列重要讲话和重要论述,系统地回答了新时代加强党的建设的重大理论和现实问题,形成了新时代全面从严治党的科学理论体系。总体看来,科学性与整体性相统一、时代性与战略性相统一、导向性与创新性相统一、实践性与人民性相统一是新时代全面从严治党内在的理论品质与基本属性。深入研究新时代全面从严治党的内在属性,系统把握习近平关于全面从严治党重要论述的精神品质,并将其贯彻落实在各级党建的具体实践中,不断厚植党的建设伟大工程的根基。

关键词：党的建设全面从严治党整体性人民性

A-UIT复合处理对7075铝合金激光焊接头摩擦磨损性能的影响

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表面技术 2021年第4期50卷 235-243页

作者：丁亚茹陈芙蓉内蒙古工业大学材料科学与工程学院呼和浩特010051 内蒙古机电职业技术学院呼和浩特010070

目的研究时效-超声冲击(A-UIT)复合处理方法对铝合金激光焊缝耐磨性的影响。方法对7075铝合金激光焊缝进行时效处理、超声冲击处理、A-UIT复合处理,对比时效处理、超声冲击处理、A-UIT复合处理后焊缝的表面硬度、表面粗糙度、3D形貌及... 详细信息

目的研究时效-超声冲击(A-UIT)复合处理方法对铝合金激光焊缝耐磨性的影响。方法对7075铝合金激光焊缝进行时效处理、超声冲击处理、A-UIT复合处理,对比时效处理、超声冲击处理、A-UIT复合处理后焊缝的表面硬度、表面粗糙度、3D形貌及扫描显微组织,并分析A-UIT复合处理、时效处理和超声冲击处理对焊缝耐磨性能的影响及机理。结果超声冲击处理的焊缝与焊态进行比较,粗糙度减小了8.65μm,表面硬度增大了47HV,摩擦系数降低了0.17,磨损率降低了70%;6、24、32 h时效处理后的粗糙度分别比焊态减小了10.18、4.19、5.88μm,表面硬度比焊态高出37、55、44HV,平均摩擦系数比焊态降低0.10、0.08、0.09,磨损率比焊态低51%、54%、61%;6、24、32 h A-UIT复合处理分别与6、24、32 h时效处理相比,粗糙度减小了9.88、10.58、8.7μm,表面硬度增大了43、44、31HV,平均摩擦系数降低了0.1、0.1、0.07,磨损率降低了35%、41%、27%。A-UIT复合处理焊缝主要以磨粒磨损为主,且存在局部剥层磨损。单独时效处理焊缝主要以浅色的剥层磨损为主,且存在少量的磨粒磨损,磨损面积较大,并伴有少量的氧化磨损。结论时效和超声冲击处理均可有效提高焊缝的耐磨性能,超声冲击处理的作用要大于时效处理,摩擦系数比24 h时效处理小15.3%,磨损率为时效处理的36.1%。A-UIT复合处理后的焊缝在纳米晶和时效强化相的共同作用下,比时效处理和超声冲击处理的焊缝耐磨性能提升更为明显。24 h A-UIT复合处理后,焊缝的摩擦系数比24 h时效处理提高了28.5%,比超声冲击状态提高了8.6%,磨损率比24 h时效处理提高了40.9%,比超声冲击状态提高了76.9%。

关键词：时效-超声冲击复合处理纳米晶摩擦系数粗糙度激光焊磨损率

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一二维模型在湖泊水环境调度中的应用比较

水电能源科学 2021年第7期39卷 61-64页

作者：陈福容上海勘测设计研究院苻限公司上海200335

以湖泊水环境调度为例,比较了一维模型、一二维耦合模型的构建方法及其在湖泊水环境调度中的应用。发现两种方法计算的调度流量、水位过程拟合程度较好;B湖引入A湖优质水资源,B湖北侧湖区Ⅲ类~Ⅳ类水体面积增加,一二维耦合模型的空间展... 详细信息

以湖泊水环境调度为例,比较了一维模型、一二维耦合模型的构建方法及其在湖泊水环境调度中的应用。发现两种方法计算的调度流量、水位过程拟合程度较好;B湖引入A湖优质水资源,B湖北侧湖区Ⅲ类~Ⅳ类水体面积增加,一二维耦合模型的空间展示效果更为直观;计算全年湖泊的水量水质调度,一二维耦合模型用了34.3h,而一维模型仅用了5.8min。通过两种方法的比较分析,提出将两种方法结合使用,以A、B湖每月连通1次、每月连通2次为例,比较论证较优的调度方案,发现每月连通1次有利于改善B湖的水质。

关键词：湖泊水环境调度一维模型一二维耦合模型

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某蓄滞洪区优化调度模型应用研究

水电能源科学 2021年第8期39卷 103-106页

作者：陈福容上海勘测设计研究院有限公司上海200335

基于水动力模型和种群单纯形进化算法PSE研究蓄滞洪区的优化调度,即以分洪闸的开关闸时间、开启孔数为决策变量,以设计蓄滞库容为约束条件,以下游断面最接近限泄流量且分洪水量最少为目标函数。分洪闸先后开启组合运用,优化计算得到4个... 详细信息

基于水动力模型和种群单纯形进化算法PSE研究蓄滞洪区的优化调度,即以分洪闸的开关闸时间、开启孔数为决策变量,以设计蓄滞库容为约束条件,以下游断面最接近限泄流量且分洪水量最少为目标函数。分洪闸先后开启组合运用,优化计算得到4个蓄滞洪区分洪总量333×10^(4)m^(3),比理论超额水量298×10^(4)m^(3)多35×10^(4)m^(3),干流出口断面满足限泄要求。与不分洪相比,控制闸的闸上水位均降低到保证水位以下;与经验调度相比,蓄滞洪区的淹没深度降低了0.9m。优化计算得到分洪闸的开关时机和开启孔数,为制定调度运行规则提供了数据支撑,亦为调度管理提供了优选方案。

关键词：蓄滞洪区优化调度水动力模型种群单纯形进化算法

Wnt3a enhances bone morphogenetic protein 9-induced osteogenic differentiation of C3H10T1/2 cells

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Chinese Medical Journal 2013年第24期126卷 4758-4763页

作者： ZHANG Xiao LIN Liang-bo XU Dao-jing chen rong-fu TAN Ji-xiang LIANG Xi, HU Ning HUANG Wei Department of Orthopedics the First Affiliated Hospital of Chongqing Medical University Chongqing 400016 China Key Laboratory of Laboratory Medical Diagnostics Ministry ofEducation Chongqing Medical University Chongqing 400016China

Background Bone morphogenetic protein 9 （BMP9） and Wnt/13-catenin signaling pathways are able to induce osteogenic differentiation of mesenchymal stem cells （MSCs）, but the role of Wnt/13-catenin signaling pathway in BMP9-induced osteogenic differentiation is not well understood. Thus, our experiment was undertaken to investigate the interaction between BMP9 and Wnt/13-catenin pathway in inducing osteogenic differentiation of MSCs. Methods C3H10T1/2 cells were infected with recombinant adenovirus expressing BMP9, Wnt3a, and BMPg＋Wnt3a. ALP, the early osteogenic marker, was detected by quantitative and staining assay. Later osteogenic marker, mineral calcium deposition, was determined by Alizarin Red S staining. The expression of osteopotin （OPN）, osteocalcin （OC）, and Runx2 was analyzed by Real time PCR and Western blotting. In vivo animal experiment was carried out to further confirm the role of Wnt3a in ectopic bone formation induced by BMP9. Results The results showed that Wnt3a enhanced the ALP activity induced by BMP9 and increased the expressions of OC and OPN, with increase of mineral calcium deposition in vitro and ectopic bone formation in vivo. furthermore, we also found that Wnt3a increased the level of Runx2, an important nuclear transcription factor of BMP9. Conclusion Canonical Wnt/13-catenin signal pathway may play an important role in BMP9-induced osteogenic differentiation of MSCs, and Runx2 may be a linkage between the two signal pathways.

关键词： bone morphogenetic protein 9, Wnt3a osteogenic differentiation, mesenchymal stem cell

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基于SAR图像的道路损毁信息提取

电子科技大学学报 2016年第4期45卷 551-556页

作者：陈彦伏晨荣卢有春童玲电子科技大学自动化工程学院成都611731

提出了一种基于多时相SAR图像的道路损毁信息提取方法。该方法首先采用粒子滤波进行道路中心线提取,针对山区的复杂环境对图像预处理和粒子滤波过程进行了调整,能正确识别山区道路中心线;然后,根据道路损毁在SAR图像中的特征,建立了道... 详细信息

提出了一种基于多时相SAR图像的道路损毁信息提取方法。该方法首先采用粒子滤波进行道路中心线提取,针对山区的复杂环境对图像预处理和粒子滤波过程进行了调整,能正确识别山区道路中心线;然后,根据道路损毁在SAR图像中的特征,建立了道路损毁模型,实现了道路损毁信息提取。实验结果表明,该方法提取的道路损毁信息准确度大于80%。

关键词：粒子滤波道路损毁道路提取合成孔径雷达