自组装金团簇电极库仑台阶现象和电化学阻抗谱研究

采用示差脉冲伏安法研究了自组装单层保护金纳米团簇(C8AuMPC)在常温下二氯甲烷溶液中的量子化电容充电效应.研究结果表明,该团簇在-0.8~0.8V电位范围内有4对明显的量子化电容充电峰.同时采用电化学阻抗谱对C8AuMPC修饰金电极体系的界面结构进行了表征,研究结果表明,MPC自组装层存在两个界面,即金电极-MPC层界面和MPC层-溶液界面;这两个界面的界面电容在MPC的零电荷电位(ca.-0.2V)附近均基本保持不变,随着电位正移或负移到一定程度,界面电容发生变化.进一步利用双隧道结金属岛库仑阻塞效应理论讨论了已有报道中对MPC量子化电容充电的理论分析结果,并证明电化学阻抗谱也是研究MPC量子化电容充电效应的有效方法.另外,用示差脉冲伏安法及循环伏安法研究了电活性物种二茂铁对C8AuMPC量子化电容充电的影响,发现溶液中的电活性物种对MPC层-溶液界面的电子传递的贡献可以忽略,表明该界面的电子传递主要发生在纳米粒子之间

FTIR-ATR Spectrometry of BSA Adsorption on Hydroxyapatite

采用傅里叶变换红外衰减全反射(FTIR-ATR)光谱法对牛血清白蛋白(BSA)在羟磷灰石(HA)[Ca_(10)(OH)_2(PO_4)_6]表面不同时间的相互吸附作用进行了表征。在BSA溶液作用下,羟磷灰石表面的Ca~(2+)、PO_4~(3-)和OH~-离子初始的溶解和再沉淀使得BSA与HA相互作用层层叠加,在HA表面形成从表层到次表层分子都包含有吸附的BSA的覆盖层,从而加深两者之间的相互作用。经红外差谱法处理过的相关ATR数据表明,BSA与HA之间的相互作用是快速的,并随时间变化进一步加强;来自HA上PO_4~(3-)的P=O基团对蛋白质肽键的酰胺Ⅱ带(-CNH)、多肽链的甲基(-CH_3)和亚甲基(-CH_2)上氢的吸附作用要比P-O快速而且强烈。Ca~(2+)在该吸附过程中起了极其重要的作用,其快速与蛋白质肽键的羰基氧发生作用,并诱导该蛋白质二级结构由β-折叠向α-螺旋和β-转角构象转变;伴随着这一构象变化,蛋白质多肽链上大多数肽键的-C=O和H-N-活性基团从链间氢键交联中释放出来,带动众多的氢分别参与同HA表面的Ca~(2+)、PO_4~(3-)和OH~-离子的相互吸附作用,并牢牢地结合于HA表面;这对硬组织的再生起着重要作用,促进了HA的生物矿化过程。The microcosmic process of bovine serum albumin(BSA) adsorbing onto hydroxyapatite(HA) for different time intervals was investigated by Fourier transform infrared attenuated total internal reflectance(FTIRATR) spectrometry.The initial dissolution and re-precipitation of PO_4~(3-),Ca~(2+),and OH~- ions from the HA coating led to the occurrence of the coating including adsorbed BSA on the HA from surface-to subsurface-molecular layers and to in-depth interaction between BSA and HA.The subtraction results gained in the adsorption regions of HA and BSA reveal that the binding of P=O,from the phosphate(PO_4~(3-)),to the hydrogen of amide Ⅱ,methyl and methene of the BSA appears to be considerably more rapid and stronger than that of the P—O group.In addition,it is very likely that Ca~(2+) plays an important role in the interaction of BSA with HA.It appears that the binding of Ca~(2+) to the carbonyl-oxygen of the peptide bond in BSA caused a significant,molecular,conformational rearrangement of polypeptide backbones from β-pleated sheet to helical circles of α-helix and β-turn.This change appears to have been followed by much hydrogen of polypeptides being driven to bind PO_4~(3-) and OH~-effectively and much-C=O and H-N- groups of the peptide bond being freed from inter-chain hydrogenbonding to act on Ca~(2+) and combine strongly with the HA surface.This might reasonably be expected to promote hard tissue regeneration.BSA seems to be activated by the inductive effect of Ca~(2+) via the molecular rearrangement of polypeptide backbones from pleated sheet to helical circles and in turn reacts strongly on the HA,resulting in profound effects on the course of biomineralization.国家自然科学基金(51571169)资助项目~

自组装单层保护金纳米团簇的量子化电容充电

本文研究自组装单层保护金纳米团簇(C12Au MPC)在常温下二氯甲烷溶液中的量子化电容充电效应.示差脉冲伏安曲线显示金核平均直径为2.0 nm的C12Au MPC在-0.6~0.6 V电位区间内有9个明显的量子化电容充电峰,其双电层电容总的变化趋势为在零电荷电位附近最小,随着电位正移或负移电容变大.而且随着该金核尺寸的增大,MPC双电层电容值也变大

用辛烷基硫醇单层保护Au纳米粒子制备CO氧化催化剂Au/γ-Al_2O_3

采用两相法合成出含活性组分Au的辛烷基硫醇单层保护Au纳米粒子(C8AuNPs)的正己烷溶胶,用"逐次浸润"法将C8AuNPs负载在γ-Al2O3上,经真空干燥及活化处理制得Au/γ-Al2O3催化剂.所制得的Au催化剂前体C8AuNPs/γ-Al2O3表面Au粒子平均粒径可控制在2-3nm范围内,且分布比较单一;催化剂活性评价600h后,其表面Au的粒径仍主要分布在2-4nm范围内;真空干燥温度影响Au催化剂的粒子尺寸和催化活性,随着真空干燥温度的提高,Au纳米粒子的粒径增大.将所制备的催化剂用于低温CO氧化反应,催化活性评价结果表明,经25℃真空干燥制得的2.5%(质量分数,w)Au/γ-Al2O3具有较高的活性和长期稳定性,其催化CO完全转化的最低温度为-19℃,在15℃下CO完全转化时Au/γ-Al2O3的单程寿命至少900h;4.0%(w)Au/γ-Al2O3在15℃和进料中含水条件下对CO完全氧化的单程寿命不低于2000h,可见催化剂具有强的抗潮湿中毒特性.综合上述实验结果,讨论了影响Au/γ-Al2O3催化剂活性的可能因素

苯胺嘧啶衍生物X-9通过下调整合素β1表达抑制肝细胞癌迁移侵袭

整合素在许多肿瘤细胞中高表达，并且参与肿瘤细胞的侵袭转移。在肝细胞癌中，整合素β1被报导高表达，并促进肿瘤细胞的侵袭。目前，对于整合素的表达调控癌细胞机制以及干预其表达进而抑制肿瘤细胞转移的研究较少。本研究探讨利用小分子化合物抑制整合素表达来抑制肿瘤细胞迁移和侵袭的可能。首先，对临床肝癌细胞患者癌组织和癌旁组织中的整合素β1的表达进行检测，发现其在癌组织中的表达显著高于癌旁组织（P<0.05）。对TCGA肿瘤数据库的生物信息学分析结果同样显示，整合素β1的高表达与肝癌的分期（P=0.019）和预后（P=0.013）相关。通过筛选发现，苯胺嘧啶衍生物X-9可以抑制肝癌细胞中整合素β1的mRNA和蛋白质的表达（P<0.01）。细胞划痕愈合实验和细胞穿孔结果显示，苯胺嘧啶衍生物X-9能够抑制肝癌细胞的迁移和侵袭（P<0.01）。进一步的研究证实，在肝癌细胞中外源表达整合素β1可以逆转X-9对肝癌细胞迁移和侵袭的抑制；而在敲除整合素β1的细胞中，X-9对细胞的迁移和侵袭的抑制被消除。因此，鉴定出苯胺嘧啶衍生物X-9可以通过下调整合素β1表达，进而抑制肝癌细胞的迁移和侵袭。福建省自然科学基金（No.2016J05087,No.2017J01201）;;福建省卫计委医疗创新项目（No.2015-CXB-15

Thirty Years of Regulatory Detailed Planning: Gains and Losses, and Prospects

吕传廷(中国城市规划学会理事,中国城市规划学会控规学术委员会主任委员,广州市城市规划编制研究中心主任,教授级高级工程师,本论坛主持人):非常高兴诸位嘉宾、代表参加由广州城市规划编制研究中心、深圳规划国土发展研究中心、重庆规划研究中心三家单位联合举办的"控制

Development of aquantitative ELISA detection method for Varicella Zoster Virus(VZV) antigen

目的:建立水痘-带状疱疹病毒(VzV)抗原的双抗体夹心ElISA定量检测方法,用于质控VzV灭活疫苗研发和生产中抗原含量。方法:以VzV中和单抗5f6C8为包被抗体、8H5d1为酶标抗体,构建定量检测VzV抗原的双抗体夹心ElISA方法,并对本方法的特异性、灵敏度、准确性、线性和稳定性等性能进行分析。结果:建立的双抗体夹心定量检测VzV抗原的ElISA方法,线性范围为0.4μg~13μg/Ml,相关系数为r2=0.994,定量限度为0.4μg/Ml;变异系数CV80%。与VzV以外的相关病毒样本没有交叉反应。结论:构建的VzV抗原ElISA定量检测方法的各项性能符合定量检测需要,可用于VzV灭活疫苗的研发和生产过程的抗原含量检测。Objective:To develop a quantitative enzyme linked immunosorbent assay(Q-ELISA) to determine the concentration of Varicella Zoster Virus(VZV) antigen.This method was used to determine VZV antigen content at each stage of VZV inactived vaccine developing and manufacturing process.Methods: A double antibody sandwich Q-ELISA was developed to determine concentration of VZV antigen,which was based on the the high-affinity neutralizing monoclonal antibodies 5F6C8 as capture antibodies,and 8H5D1 as HRP-labeled antibody.The performance of reagent were evaluated.Results: The Q-ELISA for VZV antigen content was successfully developed.The reagent had good performance.The quantitation scope was 0.4 μg~13 μg/ml,The coefficient correlation was 0.994,the limit of detection was 0.4 μg /ml,the recovery was between 87.5% and 111.6%.The stability was up to 80% after reagent was heated for 6 days at 37℃.The variation coefficient was lower than 15%,and the reagent was no reaction with other sample except VZV antigen.Conclusion: The Q-ELISA for VZV antigen was developed with good specificity,accuracy and stability.The method can be used to determine VZV antigen content during development and production of VZV inactived vaccine

2D NMR Study on Solution Structure of Natural Product 3′-Methoxy Puerarin

【中文文摘】3′ 甲氧基葛根素是从常用中药野生葛根中分离提取出来的一种具有很强生物活性的异黄酮类化合物.该化合物含季碳较多,有些13CNMR的谱峰不易归属.本文利用包括氢检测异核多量子相干谱(HMQC)和氢检测远程异核多量子相干谱(HMBC)等多种二维核磁共振技术对该天然产物的13C和1HNMR谱峰进行了全归属.这些工作有助于利用二维核磁共振技术研究和确定含季碳较多的异黄酮类新化合物的结构和利用扩散相关的核磁共振新技术研究葛根的生理活性成份与靶分子相互作用. 【英文文摘】An active isoflavone compound 3′methoxy puerarin was isolated from puerarin lobate (willd). Several twodimensional NMR new techniques, including 1Hdetected heteronuclear multiplequantum coherence and 1Hdetected multiplebond heteronuclear multiplequantum coherence, were employed to completely assign all the protons and carbons of the compound. This work solves the assignments of uncertain C3 and C1′ NMR signals in the previous literature and will be helpful to study the structures of this kind of new isoflavone compounds by 2D NMR spectroscopy and bioactive compounds in puerarin lobate directly by diffusion2chemical shift 2D NMR.国家自然科学基金(20172042);; 国家中医药管理局与福建省卫生厅基金(2000 J P 40)资助项