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Journal of Energy Chemistry 2019年第11期28卷 15-19页

作者： Yifan Zan Gai Miao Hao Wang Lingzhao Kong Yaping Ding Yuhan Sun Department of Chemistry Shanghai UniversityShanghai 200444China CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

MnOx-promoted Ni-based catalyst supported by ZnO was developed to selectively hydrogenate glucose into polyols in water at 523 K with a yield of 64.9%. Using glucose, sorbitol, glycerol and LA as the rawmaterials, the roles of nickel, ZnO and MnOx were investigated. The results show that nickel provided a new pathway of glucose to sorbitol and played an important role in the hydrogenation of C3 intermediates to 1,2-propanediol(1,2-PDO). The high yield of 1, 2-PDO was attributed to effective C–C bond cleavage performance of ZnO support promoted by MnOx. ZnO and MnOx contribute to the conversion of glycerol to lactic acid(LA) and LA to 1, 2-PDO, respectively. A concise pathway for hydrogenation of glucose over Ni-based catalyst was proposed.

关键词： Glucose Hydrogenation 1, 2-Propanediol Ethylene glycol Ni-based catalyst

The thermodynamic stability of insulin disulfides is not affected by the C-domain of insulin-like growth factor 1

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Science China(Life Sciences) 2002年第3期45卷 245-250页

作者：郭占云冯佑民 1. State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 200031 Shanghai China

Both Insulin and insulin-like growth factor 1 are members of insulin superfamily. They share homologous primary and tertiary structure as well as weakly overlapping biological activity. However, their folding behavior is different: insulin and its recombinant precursor (PIP) fold into one unique tertiary structure, while IGF-1 folds into two disulfides isomers with similar thermody-namic stability. To elucidate the molecular mechanism of their different folding behavior, we prepared a single-chain hybrid of insulin and IGF-1, [B10Glu]lns/IGF-1(C), and studied its folding behavior compared with that of PIP and IGF-1. We also separated a major non-native disulfides iso-mer of the hybrid and studied its refolding. The data showed that the C-domain of IGF-1 did not affect the folding thermodynamics of insulin, that is, the primary structure of the hybrid encoded only one thermodynamically stable disulfides linkage. However, the folding kinetics of insulin was affected by the C-domain of IGF-1.

关键词： insulin, insulin-like growth factor 1, hybrid, unfolding, refolding.

Nuclear translocation of EGF receptor regulated by Epstein-Barr virus encoded latent membrane protein 1

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Science China(Life Sciences) 2004年第3期47卷 258-267页

作者： TAO Yongguang1, SONG Xin1, TAN Yunnian1, LIN Xiaofeng2, ZHAO Yan1, ZENG Liang1, TANG Min1, LI Wei1, WU Qiao2 & CAO Ya1 1. Cancer Research Institute, Xiangya School of Medicine, Central South University, Changsha 410078, China 2. Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering, School of Life Sciences, Xiamen University, Xiamen 361005, China 1. Cancer Research Institute Xiangya School of Medicine Central South University 410078 Changsha China 2. Key Laboratory of the Ministry of Education for Cell Biology and Tumor Cell Engineering School of Life Sciences Xiamen University 361005 Xiamen China

Epstein-Barr virus (EBV) encoded latent membrane protein 1 (LMP1) is considered to be the major oncogenic protein of EBV encoded proteins, and also it has always been the core of the oncogenic mechanism of EBV. Traditional receptor theory demonstrates that cell surface receptors exert biological functions on the membrane, which neither enter into the nucleus nor directly affect the transcription of the target genes. But, advanced studies on nuclear transloca-tion of the epidermal growth factor receptor (EGFR) family have greatly developed our knowl-edge of the biological function of cell surface receptors. In this study, we used Tet-on LMP1 HNE2 cell line as a cell model, which is a dual-stable LMP1 integrated NPC cell line and the ex-pression of LMP1 in which could be regulated by Tet system. We found that LMP1 could regulate the nuclear translocation of EGFR in a dose-dependent manner from both quantitative and qualitative levels through the Western blot analysis and the immunofluorescent analysis with a laser scanning confocal microscope. We further demonstrated that the nuclear localization se-quence of EGFR played some roles in the location of the protein within the nucleus under LMP1 regulation, and the nuclear accumulation of EGFR regulated by LMP1 was in a ligand-independent manner. These findings provide a novel view that the regulation of LMP1 on the nuclear translocation of EGFR is critical for the process of nasopharyngeal carcinoma.

关键词： Epstein-Bar virus, latent membrane protein 1, epidermal growth factor receptor, nuclear translocation.

Regulatory mechanisms for abnormal expression of the human breast cancer specific gene 1 in breast cancer cells

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Science China(Life Sciences) 2006年第4期49卷 403-408页

作者： LU Aiping1, LI Qing1, LIU Jingwen2 1. Department of Pathology, Peking University School of Oncology, Beijing Cancer Hospital, Beijing 100036, China 2. VA Palo alto Health Care System, Palo Alto, California, CA 94304, USA 1. Department of Pathology Peking University School of Oncology Beijing Cancer Hospital Beijing 100036 China 2. VA Palo alto Health Care System Palo Alto California CA 94304 USA

Breast cancer-specific gene 1 (BCSG1), also referred as synuclein γ, was originally iso-lated from a human breast cancer cDNA library and the protein is mainly localized to presynaptic terminals in the nervous system. BCSG1 is not expressed in normal or benign breast lesions, but expressed at an extremely high level in the vast majority of the advanced staged breast carcinomas and ovarian carcinomas. Overexpression of BCSG1 in cancer cells led to significant increase in cell proliferation, motility and invasiveness, and metastasis. To elucidate the molecular mechanism and regulation for abnormal transcription of BCSG1, a variety of BCSG1 promoter luciferase reporters were constructed including 3′ end deleted sequences, Sp1 deleted, and activator protein-1 (AP1) domains mutated. Transient transfection assay was used to detect the transcriptional activation of BCSG1 promoters. Results showed that the Sp1 sequence in 5′-flanking region was involved in the basal transcriptional activities of BCSG1 without cell-type specificity. In comparison to pGL3-1249, the reporter activities of pGL3-1553 in BCSG1-negative MCF-7 cells and pGL3-1759 in HepG2 cells were notably decreased. Mutations at AP1 sites in BCSG1 intron 1 significantly reduced the promoter ac-tivity in all cell lines. Transcription factors, c-jun, c-fos and cyclin AMP-responsive element binding (CREB) protein, could markedly enhance the promoter activities. Thus, our results suggest that the abnormal expression of BCSG1 in breast cancer cells is likely regulated by multiple mechanisms. The 5′ flanking region of BCSG1 provides the basal transcriptional activity without cell type specificity. A critical promoter element involved in abnormal expression of BCSG1 presents in the first exon. The cell type specificity of BCSG1 transcription is probably affected through intronic cis-regulatory se-quences. AP1 domains in the first intron play an important role in control of BCSG1 transcription.

关键词： breast cancer-specific gene 1, promoter, transcriptional activity.

Impact of 1,25-(OH)_2D_3 on Left Ventricular Hypertrophy in Type 2 Diabetic Rats

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Chinese Medical Sciences Journal 2015年第2期30卷 114-120页

作者： Ying Fan Shan-xiao Zhang Meng Ren Li-feng Hong and Xiao-ni Yan Department of Cardiology the Fifth Hospital of Wuhan & Institute of Cardiovascular Sciences of Jianghan University Department of Cardiology the First Hospital of Yangtze University

Objective To investigate the impact of 1, 25-(OH)2D3 on left ventricular hypertrophy(LVH) in type 2 diabetic rats. Methods Type 2 diabetic mellitus(DM) model rats were established by intraperitoneally injecting with 30 mg/kg streptozotocin. After 8 weeks, 19 male rats were identified as diabetic with left ventricular hypertrophy(LVH) by ultrasound examination, and randomly assigned into three groups: untreated(DM-LVH, n=7), treated with insulin(DM-LVH+INS, n=6), and treated with 1, 25-(OH)2D3(DM-LVH+VD, n=6). Healthy male rats were used as the controls group(n=6). The fasting blood glucose and the insulin level were determined weekly. The left ventricular mass index, myocardial collagen content, collagen volume fraction, and 1, 25-(OH)2D3-receptor level were determined by 4 weeks later. Results In the DM-LVH model group, the insulin level was significantly decreased compared with the non-diabetic control group(P1, 25-(OH)2D3-receptor expression were significantly increased(all P1, 25-(OH)2D3 could reverse LVH in diabetic rats and that the mechanism may involve stimulating insulin secretion and reducing blood glucose via direct up-regulation of 1, 25-(OH)2D3-receptor expression.

关键词： 1, 25-(OH)2D3 left ventricular hypertrophy type 2 diabetes mellitus rat

一种简单快速检测汞离子的1,4-二硫苏糖醇膜修饰金平板电极

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高等学校化学学报 2014年第7期35卷 1388-1395页

作者：曹婷婷曹忠何婧琳梁海琴肖忠良长沙理工大学化学与生物工程学院、电力与交通材料保护湖南省重点实验室长沙410004

将1，4-二硫苏糖醇（DTT）自组装在100nm厚的平整金膜表面，形成DTT膜修饰金平板电极（GPE），构建了一种新颖的简单、快速测定汞离子的选择性电极分析方法．通过电化学交流阻抗和循环伏安法探讨了该电极的响应原理，即固定在Au表面的DT... 详细信息

将1，4-二硫苏糖醇（DTT）自组装在100nm厚的平整金膜表面，形成DTT膜修饰金平板电极（GPE），构建了一种新颖的简单、快速测定汞离子的选择性电极分析方法．通过电化学交流阻抗和循环伏安法探讨了该电极的响应原理，即固定在Au表面的DTT通过另一端的巯基与汞离子发生强配位作用而吸附结合带正电荷的汞离子，引起电极表面膜电位的变化，从而选择性地识别汞离子．实验结果表明，该电极在pH=6．0的Tris-HCl缓冲溶液中对汞离子有良好的电位响应性能，其线性范围为1．0×10^-8～1．0×10^-3mol／L，能斯特响应斜率为（29．62±0．2）mv／-pc（25qC），检出限为5．1×10^-9mol／L．该汞离子检测电极的响应时间仅为20s，且有较好的重现性和稳定性．通过测定各种离子的选择性系数，发现Cu2＋，Fe2＋，Na＋，K＋，Mg2＋，Ba2＋，Ca2＋，Zn2＋，Sn2＋，Pb2＋，Ag＋，Al3＋，Fe3＋，Ni2＋，N02-，IO3-，BrO3-和ClO3等离子不干扰该电极对汞离子的检测．此外，将该电极用于实际水样中微量汞离子含量的测定，结果与双硫腙分光光度方法一致，且回收率为98．20％～101．75％．

关键词：金平板电极 1, 4-二硫苏糖醇自组装膜汞离子选择性识别

极少量1,4-戊二烯对典型Ziegler-Natta催化剂催化的丙烯聚合反应及聚丙烯性质的影响

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高分子学报 2015年第4期25卷 410-417页

作者：马琳秦亚伟董金勇中国科学院化学研究所中国科学院工程塑料重点实验室北京100190 中国科学院大学北京100049

以9,9-二(甲氧基甲基)芴(BMMF)为内给电子体的MgCl2/TiCl4催化剂与三乙基铝(TEA)组成典型Ziegler-Natta催化剂体系,催化丙烯本体聚合,考察极少量1,4-戊二烯作为共聚单体对聚合反应行为的影响.结果发现,在[1,4-戊二烯]/[丙烯]共单体摩尔... 详细信息

以9,9-二(甲氧基甲基)芴(BMMF)为内给电子体的MgCl2/TiCl4催化剂与三乙基铝(TEA)组成典型Ziegler-Natta催化剂体系,催化丙烯本体聚合,考察极少量1,4-戊二烯作为共聚单体对聚合反应行为的影响.结果发现,在[1,4-戊二烯]/[丙烯]共单体摩尔比非常低(1%)的范围内,随着1,4-戊二烯浓度增大,催化剂活性迅速降低,[1,4-戊二烯]/[丙烯]比为0.08%时仅为约初始的1/4.但由特性黏数得到的聚合物分子量对1,4-戊二烯浓度呈现不规则变化,1,4-戊二烯并未使聚合物分子量单调降低,而在极低浓度时反而使其有所提高.凝胶渗透色谱(GPC)表征结果不但进一步确认了聚合物分子量的变化规律,还表明1,4-戊二烯并未使聚合物链发生支化.动态剪切流变测试结果显示极少量的1,4-戊二烯使聚合物的剪切黏度上升,模量提高,松弛时间延长;聚合物的拉伸黏度在拉伸流变测试中呈现相同的规律.通过1,4-戊二烯/氢气在聚合反应中协同作用的探讨,提出了对MgCl2/TiCl4/BMMF-TEA催化的丙烯/1,4-戊二烯反常共聚合行为的解释.

关键词： Ziegler-Natta催化剂丙烯 1, 4-戊二烯共聚合

双枝[1,3,4]-噁二唑衍生物的合成与荧光性质

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有机化学 2009年第1期29卷 71-77页

作者：孟康钱鹰东南大学化学化工学院南京211189

通过Wittig反应和Heck反应合成了三个双枝噁二唑衍生物:N-{{{3,5-二-[5-(4-叔丁基苯基)-1,3,4-噁二唑-2]-苯基}-E-乙烯基}-4-苯基}二苯胺(BBOD-2),N,N-双{{{3,5-二-[5-(4-叔丁基苯基)-1,3,4-噁二唑-2]-苯基}-E-乙烯基}-4-苯基}苯胺(BBOD-3),N,N,N-三{4-{2-{3,5-二-[5-(4-叔丁基苯基)-1,3,4-噁二唑-2]-苯基}-E-乙烯基}苯基}胺(BBOD-4).化合物结构经过红外光谱、核磁共振谱、质谱和熔点确证,测定了它们在不同溶剂中的紫外光谱和单光子荧光光谱.BBOD-1,BBOD-2,BBOD-3,BBOD-4在二氯甲烷中的最大吸收峰分别位于295,390,398和408nm;最大发射峰分别为360,486,483和487nm.讨论了Stokes位移与溶剂极性的关系.

关键词： 1, 3, 4-噁二唑衍生物 Wittig反应 Heck反应荧光性质

超声波辅助下合成一些1,8-萘酰亚胺衍生物

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有机化学 2011年第4期31卷 557-562页

作者：张业王凯义祥辉覃雯王恒山广西师范大学化学化工学院桂林541004 桂林师范高等专科学校化学与工程技术系桂林541001

在超声波辅助下,使1,8-萘酐、4-溴-1,8-萘酐、3-硝基-4-溴-1,8-萘酐分别与伯胺反应合成了一系列1,8-萘酰亚胺衍生物,该方法与常规合成方法相比具有反应时间短、条件温和、产率高等优点.

关键词： 1, 8-萘酰亚胺超声波合成结构表征

产1,3-丙二醇新型重组大肠杆菌JM109(pHsh-dhaB-yqhD)的构建及其转化甘油

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化工学报 2006年第12期57卷 2920-2925页

作者：张晓梅诸葛斌谢涛唐雪明方慧英诸葛健江南大学工业生物技术教育部重点实验室江苏无锡214036

利用温控载体pHsh将编码甘油脱水酶的基因dhaB和编码1,3-丙二醇氧化还原酶同工酶的基因yqhD串联构建重组质粒pHsh-dhaB-yqhD,将其转化大肠杆菌得到新型产1,3-丙二醇重组大肠杆菌JM109(pHsh-dhaB-yqhD),并对影响该重组菌发酵的营养因子... 详细信息

利用温控载体pHsh将编码甘油脱水酶的基因dhaB和编码1,3-丙二醇氧化还原酶同工酶的基因yqhD串联构建重组质粒pHsh-dhaB-yqhD,将其转化大肠杆菌得到新型产1,3-丙二醇重组大肠杆菌JM109(pHsh-dhaB-yqhD),并对影响该重组菌发酵的营养因子进行研究.实验结果表明:该重组菌转化甘油合成1,3-丙二醇的适宜培养基组成为甘油60g·L-1、酵母膏5·0g·L-1、维生素B120·05g·L-1以及KH2PO47·5g·L-1;以此培养基在5L发酵罐上进行放大,1,3-丙二醇产量、转化率和生产能力分别达到43·26g·L-1、72·2%和1·55g·L-1·h-1.

关键词： 1, 3-丙二醇重组大肠杆菌甘油营养因子