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Chinese Science Bulletin 2001年第2期46卷 148-153页

作者： Jianguo Ren Huili Xia yaoren dai Tsing Hua Univ Dept Biol Sci & Biotechnol Beijing 100084 Peoples R China

The changes in telomerase activity and telomere length during apoptosis in HeLa cells as induced by sodium butyrate (SB) have been studied. After a 48 h SB treatment, HeLa cells demonstrated characteristic apoptotic hallmarks including chromatin condensation, formation of apoptotic bodies and DNA Laddering which were caused by the cleavage and degradation of DNA between nucleosomes. There were no significant changes in telomerase activity of apoptotic cells, while the telomere length shortened markedly. In the meanwhile, cells became more susceptible to apoptotic stimuli and telomere became more vulnerable to degradation after telomerase activity was inhibited. All the results suggest that the apoptosis induced by SB is closely related to telomere shortening, while telomerase enhances resistance of HeLa cells to apoptotic stimuli by protecting telomere.

关键词： telomerase telomere apoptosis sodium butyrate.

Assaying poly(ADP-ribose) polymerase activity in plants by polarographic method

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Chinese Science Bulletin 1999年第20期44卷 1883-1887页

作者： Ruihua Tian Depu Chen yaoren dai Tsing Hua Univ Dept Biol Beijing 100084 Peoples R China Tsing Hua Univ Dept Chem Beijing 100084 Peoples R China

A new method has been developed to assay poly(ADP-ribose) polymerase (PARP) activity in plant tissues through determining the content of nicotinamide (NIC) produced by enzymatic reaction by linear sweeping polarographic method. The detection limit of NIC was 0.03μmol/L, the calibration graph was linear up to 5μmol/L ( r = 0.999). The recoveries were approximately in the range of 92% to 98% and the relative standard deviations were less

关键词： linear sweeping polarographic method NAD+ nicotinamide nuclei poly( ADP-ribose) polymerase (PARP).

Apoptosis in suspension culture of tobacco cells induced by heat shock

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Chinese Science Bulletin 1999年第12期44卷 1101-1106页

作者： Haoming Chen Changhui Yan Xiaofang Jiang yaoren dai Tsing Hua Univ Dept Biol Beijing 100084 Peoples R China

The induction of apoptosis in suspension culture of tobacco cells by heat shock is reported for the first time. Heat treatment (48℃ for 4 h) of tobacco cells led to the appearance of typical hallmarks of apoptosis. It was demonstrated by DNA laddering analysis that the cells treated with heat shock at 48℃ for 4 h had a serious degradation of nuclear DNA into multi-nu-cleosomal sizes, suggesting that heat shock activated endogenous nuclease which led to DNA cleavage at the linkage sites between the nucleosomes, but ladders were very faint for DNA from 2 and 9 h heat-treated cells. The terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labelling (TUNEL) detection also showed that most of these treated cells (48℃ for 4 h) displayed positive reactions, indicating a serious DNA 3’-OH cleavage in their nuclei. Moreover, some other cytological changes in apoptotic cells, such as cell shrinkage, chromatin aggregation, nucleus collapse, have also been observed by 4’,

关键词： apoptosis DNA ladder TUNEL Nicotiana tabacum .

Menadione-induced apoptosis and its mechanism in plants

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Chinese Science Bulletin 2000年第4期45卷 350-354页

作者： SUN Yingli ZHOU Jun dai yaoren ZHAI Zhonghe College of Life Sciences Peking UniversityBeijing 100871China Biology Department Tsinghua UniversityBeijing 100084China

Menadione can induce apoptosis in tobacco protoplasts, Typical characteristics are detected including the condensation of chromatin, the formation of apoptotic bodies and the degradation of genomic DNA into 'DNA ladder'. Specific DNase is activated during this process. Ca2+ and Mg2+ are necessary for its activation, while 2n2+ and EDTA (Ethylenediaminetetraacetic acid) can inhibit its activation. The fragmentation of DNA and lamin can be inhibited by DEVD (Ac-Asp -Glu- Val- Asp-aldehyde). The fragmentation of lamin can also be inhibited by PMSF (Phenylmethylsulfonyl fluoride) and CH (Cyclohexinide). These results show that activation of specific DNase and proteases is involved in menadion-induced apoptosis in plants.

关键词： tobacco protoplasts menadione apoptosis DNA fragmentation lamin protease.

Construction of a cell-free system using extracts from apoptotic plant cells

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Chinese Science Bulletin 1999年第16期44卷 1494-1497页

作者： Jun Zhou Haoming Chen Xiaofang Jiang Haizhen Zhu yaoren dai Tsing Hua Univ Dept Biol Beijing 100084 Peoples R China Peking Univ Coll Life Sci Beijing 100871 Peoples R China

To study the mechanism of plant apoptosis, a cell-free system has been developed using the extracts prepared from tobacco cells that become committed to apoptosis induced by heat shock treatment. Tobacco nuclei have displayed such characteristics of apoptosis as nucleus condensation and formation of apoptotic bodies during incubation in this system. Besides, these morphological changes are accompanied by DNA fragmentation, which is detected

关键词： apoptosis cell-free system protease protease inhibitor.

Expression of Bcl-2 in cells with different telomerase activities

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Chinese Science Bulletin 2001年第23期46卷 1980-1984页

作者： CHEN Jing REN Jianguo ZHENG Jianyu CAI Guoping dai yaoren Department of Biological Sciences and Biotechnology Tsinghua UniversityNational Key Laboratory of Biomembrance and Membrance BiotechnologyBeijing 100084China Institute for Molecular Biology Nankai UniversityTianjin 300071China

Both tclomerase and Bcl-2 are important genes in controlling apoptosis. The activation of telomerase and the abnormal regulation of Bcl-2 are also closely related to carcinogenesis. However, little is known about the linkage between telomerase and Bcl-2. The effect of activated telomerase on the expression of Bcl-2 has been investigated. It is demonstrated that in tumor and transformed cells with higher telomerase activity, Bcl-2 expression is significantly lower than that in telomerase negative or less telomerose activity cells. Further study showed that in the telomerase gene-transformed 2BS-fibroblasts, Bcl-2 expression is inhibited significantly while the exogenous telomerase catalyticsubunit gene is re-expressed in flbroblasts. Results indicated that there might be a certain linkage between the expression of telomerase and Bcl-2, and overexpression of exogenous telomerase gene might down regulate the expression of Bcl-2.

关键词： telomere telomerase Bcl-2.

INHIBITION OF PHOTOPERIODIC INDUCTION OF FLOWERING BY p-FLUOROPHENYLALANINE IN JAPANESE MORNING GLORY

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Chinese Science Bulletin 1988年第6期33卷 526-页

作者：戴尧仁王君 Department of Biology Peking University

Induction of flowering in Japanese morning glory was inhibited when 0.04 mol/L DL-p-fluorophenylalanine (FPA), an amino acid antimetabolite, was applied during an inductive dark period through cotyledons. The applicat... 详细信息

关键词： flowering Japanese Induction morning inductive inhibited floral bands Proteins PAGE

EFFECT OF SPERMIDINE ON ACTIVITIES OF B-TYPE MONOAMINE OXIDASE AND SUPEROXIDE DISMUTASE OF CHICK EMBRYO BRAIN CELLS IN PRIMARY CULTURES

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Chinese Science Bulletin 1988年第6期33卷 527-页

作者：辛华高崇明李薇锦戴尧仁 Department of Biology Peking University

Primary cultures of brain cells were prepared from 8-day-old chick embryos. Modified Eagle’s minimum essential medium with or without 10-6 mol/L spermidine was used. Every 4 days, fresh medium was added to replace on... 详细信息

关键词： Eagle replace chick Modified suggestion fresh cultivation superoxide granules throughout

微塑料对水体中有机污染物迁移转化及生物有效性的影响研究进展

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材料导报 2020年第21期34卷 21033-21037页

作者：代朝猛李思段艳平刘曙光涂耀仁同济大学土木工程学院上海200092 上海师范大学环境与地理科学学院上海200233

微塑料是一种新兴环境污染物,广泛存在于海洋和沿海环境中。微塑料比表面积大且具有疏水性,易吸附水环境中的有机污染物。其因尺寸接近水生生物的摄食直径,极易被生物摄取,从而沿着食物链发生富集现象,近年来引发了全球的广泛关注。目... 详细信息

微塑料是一种新兴环境污染物,广泛存在于海洋和沿海环境中。微塑料比表面积大且具有疏水性,易吸附水环境中的有机污染物。其因尺寸接近水生生物的摄食直径,极易被生物摄取,从而沿着食物链发生富集现象,近年来引发了全球的广泛关注。目前有关微塑料的文章对微塑料在环境中的分布和数量都做了充分的调查,并对常见微塑料与主流污染物的吸附原理和动力学进行了大量的研究。但是目前针对环境中微塑料调查的取样方法不统一,分析微塑料迁移和生物效应的模型简单且适应性弱。另外,针对微塑料与环境污染物相互作用引发的复合环境效应研究不足,研究微塑料的环境行为与生物效应的整体性易被忽视。本文首先介绍了微塑料在环境中的分布、丰度以及微塑料吸附环境中有机污染物的情况;然后分析了水环境中微塑料对持久性有机污染物的存在、分布和生物有效性的影响,并讨论了微塑料的种类和性质、污染物种类、环境条件等因素对微塑料环境行为的影响;最后结合微塑料与有机污染物作用特性、微塑料尺寸等因素讨论了微塑料与有机污染物的复合生物效应。微塑料种类庞杂,与环境介质中污染物作用密切,因此结合微塑料与污染物相互作用特性和环境特征讨论微塑料的环境行为意义重大。

关键词：微塑料迁移吸附解吸降解生物效应

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开关表面活性剂调控及增溶机理研究进展

材料导报 2021年第9期35卷 9218-9222页

作者：代朝猛李彦段艳平刘曙光涂耀仁同济大学土木工程学院上海200092 上海师范大学环境与地理科学学院上海200234

表面活性剂在解决土壤地下水污染问题中的应用越来越多,但传统表面活性剂与污染物难以分离,易造成二次污染。开关表面活性剂则可通过后续条件实现分离回收,能够有效解决二次污染问题。而实现开关表面活性剂的可逆转变需要调控相应的环... 详细信息

表面活性剂在解决土壤地下水污染问题中的应用越来越多,但传统表面活性剂与污染物难以分离,易造成二次污染。开关表面活性剂则可通过后续条件实现分离回收,能够有效解决二次污染问题。而实现开关表面活性剂的可逆转变需要调控相应的环境条件完成,研究表明开关表面活性剂的可逆转变可通过温度、电化学(氧化还原)、光、pH、CO_(2)/N_(2)等条件实现。为此,本文综述了开关表面活性剂的可逆调控机制及增溶机理,重点阐述了氧化还原、CO_(2)/N_(2)等触发机制和泡沫增溶机理。

关键词：开关表面活性剂可逆调控增溶机制泡沫