Kinetic analysis of TNF immune complex by using surface plasmon resonane

The kinetic analysis of the interaction between tumor necrosis factor(TNF) and its monoclonal antibody was performed by surface plasmon resonance(SPR) technique. The monoclonal antibody was immobilized to the surface of CM5 sensor chip by amine coupling. TNF at different concentrations was injected across the mAb immobilized surface. The interaction was recorded in real time and could be seen on the sensorgram. One cycle, including association, dissociation and regeneration, lasted no more than 15 min. The interaction results was evaluated using 1 : 1 Langmuir binding model. The kinetic rate constants were calculated to be: k =1.68 X 10(3) L (.) mol(-1) (.) s(-1), k(d) = 1.73 X 10(-4) s(-1), and the affinity constants K-A = 9. 7 X 10(3) L (.) mol(-1), K-r)= 1. 03 X 10(-7) Mol (.) L-1. The X-2 was 3.47, which showed that the interaction is consistent with the 1 : I model. We can see from the results that although there are two binding sites in one mAb molecule, TNF reacts with each site in an independent and noncooperative manner.

Determination of surface pK(a) of HS(CH2)(10)COOH SAMs using an electrochemical titration method

The self-assembled monolayer(SAM) of 11-mercaptoundecanoic acid [HS(CH2)(10)COOH] was formed on a gold electrode and the effect of the charge of end group on the electrochemical response of Fe(CN)(6)(3-) at the SAM modified electrode was studied by cyclic voltammetry. At high pH, when the -COOH groups are dissociated, the current of Fe(CN)(6)(3-) is suppressed; as the solution pH is lowered, the current of Fe(CN)(6)(3-) increases. The electrochemical titration curve was obtained by correlating the currents of Fe(CN)(6)(3-) to the different pH values of electrolyte, from which the surface pK(a) was obtained to be 3. 0+/-0. 2. Furthermore, the reason of small pK(a) value was explained using SAMs of different surface coverage.

A ferric molybdenum phosphate with a tunnel: hydrothermal synthesis and structure of (NH3CH2CH2NH3)(2)center dot(NH3CH2CH2NH2)(3)center dot Na center dot[Fe2Mo12O30(PO4)(HPO4)(4)(H2PO4)(3)]center dot 7H(2)O

A new ferric molybdenum phosphate containing a tunnel structure and crystallographically different clusters has been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction. A probe reaction of the oxidation of acetaldehyde with H2O2 using the tide compound as catalyst was carried out in a liquid-solid system, showing that the title compound had high catalytic activity in the reaction. (C) 1998 Elsevier Science S.A. All rights reserved.

用超微电极研究二茂铁等物质在聚电解质聚乙二醇·高氯酸锂中的伏安行为

用超微电极研究了聚电解质聚乙二醇·高氯酸锂（ＰＥＧ·ＬｉＣｌＯ４）的电化学性能。用伏安法研究了气体、有机小分子、温度、支持电解质、聚合链长的影响。结果表明，有机小分子有增塑效应；物质的扩散速率随温度的上升而增加，随支持电解质中阳离子半径增大而增加，随聚合物链长增加而减小。用粘度和自由体积理论解释了此现象。定性地描述了电子自交换对扩散的贡献。

同多酸和杂多酸修饰微电极的电化学研究 Ⅶ.磷钒钼杂多酸薄膜修饰微电极和杂多酸/聚苯胺薄膜修饰微电极的制备和电化学性质

本文详细描述了磷钒钼杂多酸（PV2Mo10）极薄膜修饰碳纤维（CF）微电极和PV2Mo10／聚苯胶（PAn）薄膜修饰微电极的制备及其电化学性质。

Yb(C_6Me_6)(AlCl_4)_3·MeC_6H_5的合成及其晶体结构

中性芳烃π键金属配合物在成键机制,反应性能方面都有自己的特点,并能催化烯烃聚合,齐聚合或烷基化反应。研究它们的合成,结构和反应性能,无论在理论上还是在实际上都是十分有意义的。近年来,相继报道了 Sm(C_6Me_6)(AlCl_4)_3(1),Ln(C_6H_6)(AlCl_4)_3(2)和Sm(MeC_6H_5)(AlCl_4)_3(3)的合成及结构,但是以上这些配合物都是采用 Friedel—Crafts法合成的。最近我们发现AICI_3,YbC_3,C_6Me_6直接反应可以方便地合成这些配合物。与现用的Friedel—Crafts相比,不仅简化了操作步骤,还提高了产物收率。本文将简要报道这一结果。

5-α-(磷酸基)苄基-2-甲基-4-羟基咪唑衍生物的电子轰击质谱研究

由于在农药方面的广泛应用,新的有机磷化合物不断被合成。质谱是研究其结构的重要手段之一。总结不同类型有机磷化合物的质谱裂解规律将有助于识别未知的有机磷化合物。本文所研究的5—α—[磷酸基]苄基—2—甲基—4—羟基咪唑衍生物是合成的新型除草剂,质谱未见报道。本工作在低分辨EI谱的基础上,根据高分辨精确质量测量和B/E、B_2/E联动扫描亚稳离子测定数据,研究了该类化合物的质谱断裂机理。着重讨论了该类化合物的共同质谱特征,如:P—C,P—N键的断裂;产物离子的开环反应;产物离子的H重排反应和失去CO的反应等。为该类化合物的结构研究提供依据。

STUDY ON DEPOSITION POTENTIALS OF LITHIUM AND SODIUM-IONS AND DEPOLARIZATION IN BINARY CHLORIDE

Deposition potentials of Lithium and Sodium ions have been measured in binary chloride systems (LiCl-KCl, NaCl-KCl) by I-V curve method, to provide a theoretical base for preparing high purity Al-Li alloy by electrolysis in molten salt. The changes of free energy and enthalpy were calculated in terms of depolarization values on Al cathode. Thermodynamic meaning of depolarization was discussed in details and the empirical relation between binary alloy type and depolarization type was proposed. It is shown for the first time that the presence of a third element in Al-Li alloy can strengthen depolarization of Li ion at Al alloy cathode and give foundation for preparing high purity Al-Li-M ternary alloy. The effect of LiCl concentration on deposition potentials of Li ion at Al cathode in KCl-LiCl melt was studied and average active coefficient of LiCl was obtained.

二元氯化物熔体中锂和钠离子析出电位的测定及去极化作用的研究

本文利用Ⅰ-Ⅴ曲线法测定了锂和钠离子在二元混合氯化物体系(LiCl-KCl;NaCl-KCl)中的析出电位,为利用熔盐电解法制备低钠高纯铝-锂合金提供了理论依据.根据锂离子在铝阴极上产生的去极化值求出铝和锂发生合金化反应的热力学意义,提出二元合金类型与极化类型之间的经验关系.首次通过研究锂离子在铝合金电极上的去极化行为,发现某些第三合金元素的存在可以加强锂离子的去极化作用,为进一步制取低钠高纯三元铝-锂-M合金系列提供了参考.还研究了在氯化钾-氯化锂体系中,氯化锂浓度对锂离子在铝阴极上析出电位的影响,求出了氯化锂的平均活度系数.

Effects of ultra-violet irradiation on sperm motility and diploid gynogenesis induction in large yellow croaker (Pseudosciaena crocea) undergoing cold shock

Large yellow croaker, Pseudosciaena crocea, exhibit sexually dimorphic growth, with females growing faster and reaching larger adult sizes than males. Thus, development of techniques for preferentially producing females is necessary to optimize production of these species. We have established a protocol to produce all-female croaker P. crocea through induction of meiotic gynogenesis with homologous sperm. The first set of experiments investigated the ultra-violet (UV) irradiation on sperm motility and duration of sperm activity to determine the optimal UV dosage for genetic inactivation of sperm, yet retaining adequate motility for activation of eggs. Milt from several males was diluted 1: 100 with Ringer's solution and UV irradiated with doses ranging from 0-150 J cm (-2). The results indicated that motility and duration of activity generally decreased with increased UV doses. At UV doses greater than 105 J cm(-2), after fertilization, motility was < 10% and fertilization rates were significantly lower. Highest hatching rate was obtained at 75 J cm -2. A second set of experiments was carried out to determine appropriate conditions of cold shock for retention of the 2nd polar body in P. crocea eggs after fertilization with UV-inactivated sperm by altering the timing, temperature and duration of shock. At 208 degrees C, shock applied at 3 min after fertilization resulted in higher survival rate of larvae at 6 h after hatching. Results of different combinations of three shock temperatures ( 28 degrees C, 38 degrees C or 48 degrees C) and five shock durations ( 4 min, 8 min, 12 min, 16 min or 20 min) at 3 min after fertilization demonstrated that shocks of 12 min gave highest production of diploid gynogens. Statistical analysis revealed that maximum production of diploid gynogens (44.55 +/- 2.99%) were obtained at 38 degrees C. The results of this study indicate that the use of UV-irradiated homologous sperm for activation of P. crocea eggs and cold shock for polar body retention is an effective method for producing gynogenetic offspring.

添加钛镁元素对热浸镀锌层性能的影响

热浸镀锌及其合金在世界各国已得到广泛的应用。为提高镀锌层性能，往镀浴中添加各种微量元素已经有了许多研究。但是对于在高纯锌中添加微量元素，排除由于锌浴不纯而导致的性能差异，报道很少。 本文选择高纯锌，在排除其它元素干扰的情况下，制备了添加钛、镁元素的热浸镀锌合金镀层，考察了分别添加钛、镁元素及同时添加钛镁元素后镀层在海水环境中的腐蚀行为及其耐蚀性能。 由于钛熔点（1668℃）远高于锌熔点（419.5℃），镁在高温下极易氧化，因而制备中间合金。在分别用分光光度法和原子吸收法测定准确含量后，按计算量进行添加。热浸镀层最外层和镀液合金成分基本一致，镀液合金性能可以反映镀层性能，制备锌钛、锌镁合金电极，进行电化学性能测试，发现添加钛、镁元素能够提高合金在海水中的耐腐蚀性能。 采用烘干溶剂法进行热浸镀，选择合适的工艺条件，助镀剂为ZnCl2、NH4Cl的混合溶液，温度460℃，镀液为添加不同含量钛镁的锌液。对所得镀层进行表观质量检测，镀层质量合格，其中添加钛元素后镀层亮度增加。镀层厚度是考察镀层性能的重要指标，通过测量发现镀层比较均匀，添加钛元素后镀层厚度减薄，添加镁元素后镀层厚度稍有增加，同时添加钛镁元素，镀层厚度稍高于单独添加钛元素，但比纯锌镀层要薄许多。添加微量钛镁后，镀层阻抗谱图和极化曲线图形状都没有大的改变，EIS等效电路拟合结果表明添加钛镁元素后镀层极化电阻增加，镀层在海水中耐蚀性能有所提高。 为进一步检测镀层的耐蚀性能，进行了中性盐雾试验，添加钛镁元素后镀层腐蚀失重减少，腐蚀失重率降低，耐盐雾腐蚀性能提高；室内模拟全浸实验所的结果与盐雾试验具有一致性，镀层刚开始时腐蚀较快随后比较稳定。

皱纹盘鲍热休克蛋白70基因的克隆、表达及应用

热休克蛋白70是热休克蛋白家族中最重要的一类家族成员，它具有“分子伴侣”、细胞保护、抗凋亡以及肿瘤免疫治疗等独特复杂的生物学功能，它的研究已成为生命科学领域研究的热点之一。采用RACE方法从皱纹盘鲍中克隆到一种HSP70基因的全长cDNA序列，该序列与其它物种的HSP70基因高度同源。克隆得到的皱纹盘鲍HSP70基因的全长cDNA序列为2631bp，开放阅读框为1968bp，另外其5'-和3'-非翻译区长度分别是90和573bp，其中3'-非翻译区具有AATAAA mRNA加尾信号及PolyA寡聚腺苷酸。开放阅读框编码655个氨基酸，包含N端包含的382个氨基酸的ATP酶结合域（约45kDa）、由161个氨基酸编码的底物肽结合结构域（18kDa）及112个氨基酸编码的C端结构域（10kDa）。构建了含有皱纹盘鲍HSP70的表达载体，以期得到体外表达的重组热激蛋白70，为制备抗体，通过Western blot杂交或酶联免疫等方法检测HSPs蛋白表达情况作准备。 为了研究皱纹盘鲍HSP70的转录表达，采用半定量RT-PCR方法，对HSP70不同组织及热休克、鳗弧菌感染下的转录表达情况分析。试验结果表明，采用热应激及鳗弧菌处理皱纹盘鲍，均能导致皱纹盘鲍肌肉中HSP70 mRNA转录水平明显增加，并在处理后96 h恢复至正常水平；与肌肉组织不同的是，鳃组织在温度及鳗弧菌处理后12 h后达到最高值，并一直维持相对较高的表达水平。在温度和鳗弧菌处理下，皱纹盘鲍HSP70上调表达表明HSP70的响应没有胁迫特异性，可能参与了皱纹盘鲍的免疫反应。 以皱纹盘鲍近交和杂交群体为材料，研究了不同群体的生长速率和HSP70的表达量的差异。试验结果表明，在较低的处理温度下，皱纹盘鲍近交群体HSP70的表达量高于杂交群体，随着处理温度的升高，在接近致死温度时，杂交群体的HSP70表达量要高于近交群体；不同群体达到最大HSP70表达量时的温度（Tpeak）也不同，近交群体的Tpeak为26C，低于杂交群体（28C）；近交群体的最大HSP70表达量高于杂交群体。以上试验结果表明杂交群体的HSP70的表达变化幅度较近交群体的变化幅度小，具有更宽的温度适应性。可能提供了关于杂交能够缓解皱纹盘鲍内在遗传压力的证据。 用荧光定量PCR方法分析不同壳色皱纹盘鲍在热激胁迫下不同恢复时间和南方与北方越冬的皱纹盘鲍在不同程度温度胁迫下的HSP70变化。在南方与北方越冬的皱纹盘鲍由于其越冬环境的温度明显不同，表现出明显的热响应差异。具体表现如下几个方面：首先，两个群体在非胁迫的正常条件下，其HSP70的初始表达量明显不同。南方越冬群体在其正常生长温度下（16C）的表达量高于北方群体的相应的表达量（12C）；其次，随着热激温度的增高，两个群体HSP70的表达量升高的幅度也不同。第三，两个群体HSP70表达量达到最高值后，随着温度的升高，表达量开始下降，但两个群体的表达量下降幅度也有所不同。结果表明在南方的适用后，体内可能聚集了较多的热休克蛋白，可能更有利于渡过北方的高温季节。