表面等离子共振检测葡萄糖浓度的数据处理方法

根据表面等离子共振(SPR)检测葡萄糖浓度时信号和噪声的特点,研究了寻找曲线最低点算法和基线动态调整方法等SPR数据后处理方法.采用加权质心法精确地捕获到了表面等离子共振曲线的最低点,采用固定计算点数的动态基线法调整基线位置,消除了基线附近点值的波动对测量结果的影响.模拟仿真及实验验证结果表明,采用固定点数的动态基线法和加权质心法处理SPR数据,能显著提高SPR检测葡萄糖的分辨率,在葡萄糖浓度检测技术中有很好的应用前景.     

Selectivity determinants of the aldose and aldehyde reductase inhibitor-binding sites

Aldose reductase and aldehyde reductase belong to the aldo-keto reductase superfamily of enzymes whose members are responsible for a wide variety of biological functions. Aldose reductase has been identified as the first enzyme involved in the polyol pathway of glucose metabolism which converts glucose into sorbitol. Glucose over-utilization through the polyol pathway has been linked to tissue-based pathologies associated with diabetes complications, which make the development of a potent aldose reductase inhibitor an obvious and attractive strategy to prevent or delay the onset and progression of the complications. Structural studies of aldose reductase and the homologous aldehyde reductase in complex with inhibitor were carried out to explain the difference in the potency of enzyme inhibition. The aim of this review is to provide a comprehensive summary of previous studies to aid the development of aldose reductase inhibitors that may have less toxicity problems than the currently available ones. Received 4 December 2006; received after revision 12 February 2007; accepted 20 April 2007     

Pyruvate dehydrogenase kinase regulatory mechanisms and inhibition in treating diabetes, heart ischemia, and cancer

The fraction of pyruvate dehydrogenase complex (PDC) in the active form is reduced by the activities of dedicated PD kinase isozymes (PDK1, PDK2, PDK3 and PDK4). Via binding to the inner lipoyl domain (L2) of the dihydrolipoyl acetyltransferase (E2 60mer), PDK rapidly access their E2-bound PD substrate. The E2-enhanced activity of the widely distributed PDK2 is limited by dissociation of ADP from its C-terminal catalytic domain, and this is further slowed by pyruvate binding to the N-terminal regulatory (R) domain. Via the reverse of the PDC reaction, NADH and acetyl-CoA reductively acetylate lipoyl group of L2, which binds to the R domain and stimulates PDK2 activity by speeding up ADP dissociation. Activation of PDC by synthetic PDK inhibitors binding at the pyruvate or lipoyl binding sites decreased damage during heart ischemia and lowered blood glucose in insulin-resistant animals. PDC activation also triggers apoptosis in cancer cells that selectively convert glucose to lactate. Received 25 August 2006; received after revision 20 November 2006; accepted 20 December 2006     

Inhibition of glucose transport in human erythrocytes by 2,3-dioxoindole (Isatin)

10 mM isatin (2,3-dioxoindole) inhibited glucose influx into human erythrocytes by over 30%. The inhibition is of the competitive type, where the affinity constant (K_t) was increased from 5.71 (control) to 11.11 mM in the presence of isatin with no change in V_max (130 nmol/min/ml packed cells). The observed inhibition of sugar transport by isatin was not mediated through membrane–SH groups accessible to iodoacetate, iodoacetamide, DTNB, DNP or sodium arsenite. Isatin inhibited sugar transport in the presence of 2 mM harmaline, an alkaloid inhibitor of Na⁺, K⁺–ATP_ase activity. The inhibition was non additive which suggests that these two compounds interact with the same or a similar site on the erythrocyte membrane.     

成对电解法制取葡萄糖酸和山梨醇

探讨了用葡萄糖成对电解氧化还原法制取葡萄糖酸和山梨醇的工艺条件，对直接电解法和间接电解法进行了研究比较，分析了它们的优缺点，以期打到实现工业化生产的途径。     

成对电解法研制葡萄糖酸及山梨醇的文献分析

本文介绍了成对电解葡萄糖，研制葡萄糖酸、葡萄糖酸锌、葡萄糖酸钙及山梨醇的有关文献，指出其各自的优缺点，并将这些文献与我们的工作进行了比较．     

芭蕉芋生产葡萄糖浆的研制

本文介绍了采用α－淀粉酶、葡萄糖淀粉酶双酶法生产工艺，直接从鲜芭蕉芋（Ｃａｎｎａｅｄｕｌｔｓ）块茎生产葡萄糖浆的方法。该法降低了原料成本，工艺操作容易，设备要求不高，葡萄糖转化率高，产品增值优于其它芭蕉芋制品。     

葡萄糖对磷酸盐生理溶液电还原反应的影响

报道了在负电位区葡萄糖的电还原的两个很好氧化还原峰［Ｅ＿（ｐｃ）＝－０．７１５Ｖ和Ｅ＿（ｐａ）＝－０．６１５Ｖ．对于Ａｇ／ＡｇＣｌ电极，在３７℃］，其葡萄糖在磷酸盐生理溶液中的浓度与还原峰电流密度呈线性。详细地讨论了这一电化学反应的机理。     

过氧化物酶活性部位的模拟及其催化显色反应的研究

本文合成了锰(Ⅲ)与meso-四(4-磺基苯)卟啉的螯合物(Mn-TPPS_4),研究了它作为过氧化物模拟酶对过氧化氢、4-氨基安替比林与苯酚显色反应的催化活性。拟订的光度法可准确地测定0～6μg/ml H_2O_2含量,1.5μg、8.0μg和40μgH_2O_2的平均回收率依次为95％、96％和100％。将显色反应与葡萄糖氧化酶催化反应偶联,测定了人血清中葡萄糖的含量,取得了满意的结果。     

Eastman－AQ－四硫富瓦烯修饰的电流式葡萄糖传感器

用牛血清白蛋白－戊二醛交联剂把葡萄糖氧化酶固定在Ｅａｓｔｍａｎ－ＡＱ－四硫富瓦烯（ＴＴＦ）修饰电极上，再在电极的表面修饰一层Ｅａｓｔｍａｎ膜，制备成葡萄糖传感器．实验表明，ＴＴＦＦ＋１，ＴＴＦ＋２都能够氧化葡萄糖氧化酶中的辅酶（ＦＡＤＨ２）．该传感器的浓度线性范围为５．０×１０－４～１．０×１０－２ｍｏｌ／Ｌ，响应时间小于４０ｓ．