CZE法用于肾上腺素的优化分离及其在马齿苋中含量测定的研究

[目的]采用区带毛细管电泳法实现去氧肾上腺素、肾上腺素和去甲肾上腺素3种化合物的优化分离,建立测定中药马齿苋中去甲肾上腺素的简便、快速的分离检测方法。[方法]采用未涂层弹性石英毛细管柱(60 cm×75μm i.d.,有效长度50 cm)作为分离通道,以含8 mmol/Lβ-CD的20 mmol/L硼砂(pH=9.5)为运行缓冲溶液,进样0.5 psi(3.447 kPa)×10 s,分离电压15 kV,检测波长215 nm,柱温25℃。[结果]3种肾上腺素在10 min内得到基线分离,且去氧肾上腺素、肾上腺素和去甲肾上腺素分别在16.74～267.84 mg/L(r=0.999 5),16.18～258.88 mg/L(r=0.999 2),16.181～94.16 mg/L(r=0.999 2)浓度范围内呈良好的线性关系,平均回收率(n=6)分别为99.16%、101.24%和98.96%,RSD均小于2.2%。同时,测得中药马齿苋中去甲肾上腺素的质量分数为0.052%。[结论]该方法简便、快速,可用于肾上腺素类药物的分离和含量测定。     

电泳分析在辣椒杂种纯度检验中的应用

通过对辣椒种子贮存蛋白进行电泳分析，发现不同类型辣椒在其种子贮存蛋白质水平上存在差异，并且这种差异在其交配种中可以表达出来。运用辣椒的这种特性可以在室内对辣椒交配种进行纯度检验，其结果与大田表现相吻合。     

Role of VE-cadherin/catenins complex in microvascular permeability during inflammation

VE-cadherin forms VE-cadherin/catenins complex by interacting with catenins, and VE-cadherin/catenins complex is an important component of adherens junctions (AJ). During inflammation, different kinds of factors can increase the microvascular permeability eventually by causing the disassembly of VE-cadherin/catenins complex.     

Screen of novel candidate regulators involved in oxidative stress-reprogrammed LPS signaling pathway by comparative phosphoprotein-affinity profiling

AIM: To determine the differences in phosphoproteome between LPS stimulated THP-1 cells with and without previous oxidative stress for screening of more potential regulators.METHODS: Differentiation of THP-1 cells into macrophages was induced by treatment with 100 μg/L PMA for 36 h. Differentiated cells were rested for additional 36 h without PMA treatment, then treated with 100 μmol/L H₂O₂ or medium for 1 h followed by LPS or medium treatment for 30 min. After desalted, phosphoproteins were enriched by phosphoprotein metal affinity column, and were run on 2-D electrophoresis, then the spots were analyzed to show the difference between LPS group (cells treated with LPS alone) and H₂O₂+LPS group (LPS stimulated cells also pretreated with H₂O₂). Finally, some of these spots were identified by MS and subsequent bioinformatic analysis was also conducted. RESULTS: Compared to LPS group, 29 reproducibly changed spots on the 2-D map in H₂O₂+LPS group were visualized and selected for MS analysis. Among these, 12 down-regulated spots (include those disappeared), 17 up-regulated spots (include those newly emerged) were selected. Up to now, 5 of these were identified, which were shown to be involved in various cellular processes such as proteolysis, signal transduction and protein folding. Among these, proteasome beta-4 subunit, which was dramatically down-regulated in H₂O₂+LPS group, was a major component of the proteasome complex and might participate in LPS signalling through various ways.CONCLUSION: With comparative phosphoprotein-affinity profiling, the interference brought by highly abundant house-keeping proteins is minimized, rendering us to detect less abundant signalling molecules. Aforementioned 5 proteins, especially proteasome beta-4 subunit, might be involved in LPS pathway reprogrammed by oxidative stress.     

The essential mechanics of capillary crumbling of structured agricultural soils

In soil loosening processes like seedbed preparation, significant soil crumbling is often desired. A better understanding of the mechanics of crumbling is necessary to optimize crumbling operations, particularly in structured agricultural soils in which capillary bonds are dominant. To this end, a model of the mechanics of capillary crumbling in structured agricultural soils is developed. Four sets of experiments on cylindrical soil samples were carried out to investigate the validity of the model and soil crumbling characteristics as influenced by freezing, thawing and drying. After preparation and sample pre-treatment, the samples were dried to different moisture contents and then tested to determine soil bonding strength. Soil water suction was also monitored at testing as were sample dimensions at different stages of experimentation. The model was found to account satisfactorily for the mechanics of capillary crumbling in structured agricultural soils. Freezing had the effect of reducing the strength of inter-aggregate bonds whilst preserving the integrity of soil aggregates during crumbling.     

柴达木黄牛和青海东部黄牛血红蛋白的多态性

采用聚丙烯酰胺凝胶电泳对１６９头柴达木黄牛和２５６头青海东部黄牛血红蛋白的多态性特征进行了研究。结果发现：（１）柴达木黄牛和青海东部黄牛血红蛋白的多态性受ＨＢ＾Ａ,ＨＢ＾Ｂ和ＨＢ＾Ｃ等３个等位基因控制,以ＨＢ＾Ａ和ＨＢ ＡＡ为优势基因和基因型;（２）柴达木黄牛与青海东部黄牛血红蛋白多态性特征相似。     

Determination of wheat bug (Eurygaster spp.) damage in durum wheat (Triticum durum L.) by electrophoresis and rapid visco analyser

The degradation effects of wheat bug protease(s) on glutenin proteins of durum wheat cultivars were investigated by electrophoresis and modified rapid visco analyser (RVA) test. Glutenin patterns of the bug damaged durum wheats changed substantially due to bug protease(s). Although high molecular weight glutenin subunits (HMW-GS) of three cultivars (Ege, Svevo, and Zenith) disappeared after 60 min of incubation, the HMW-GS of other two cultivars (Diyarbakir and Firat) were still visible even after the longest incubation period at medium damage level. It shows that there was an intercultivar variation in susceptibility to hydrolysis by bug proteolytic enzymes. Low molecular weight glutenin subunits of all cultivars decreased substantially after 30 min of incubation. The RVA curves indicated a clear reduction in viscosity in semolina samples with both medium and high damage levels as compared to their respective undamaged (control) samples. There were significant correlations (p < 0.001) between bug damage level and viscosities at 3 min (r = −0.765), at 4.5 min (r = −0.549) and at 10 min (r = −0.835), breakdown value (r = −0.534) and decay rate (r = 0.600). Consequently, hydrolysis rate of wheat bug protease(s) can be determined by modified RVA technique without much more chemicals, procedures and expensive equipments.     

Evaluation of genetic diversity of sweet potato [Ipomoea batatas (L.) Lam.] on different ploidy levels applying two capillary platforms

The genetic composition of sweet potato [Ipomoea batatas (L.) Lam.] (2n = 6x = 90) is reflected in different levels of genetic variation. The main objective of the present study was a comparison of genetic diversity parameters of different ploidy levels (2n, 4n, and 6n codominant allele determination), analyzed on two high-resolution capillary platforms. Fragment analysis was performed by applying SSR markers on a 3130XL Genetic Analyzer (ABI 3130) and QIAxcel Advanced System (QX). A high level of expected heterozygosity (He) as a measure of genetic diversity was observed for both ABI3130 (0.731) and QX (0.679). Molecular variance was 17% for ABI3130 and 10% for QX. Comparison between genetic distance matrices based on allele lengths showed a moderate Mantel correlation coefficient (rxy = 0.557) between ABI3130 and QX. Global cluster analysis using the Bayesian approach distributed the observed genotypes into two clusters on both capillary platforms. Our results show that the two high-resolution capillary electrophoreses for codominant data on 2n, 4n, and 6n levels are applicable in genetic diversity studies but their efficiency depends on in-resolution expectations, financial resources, available time, and the equipment of the laboratory.     

鸡SIgA的纯化及兔抗鸡SIgA抗体的制备

采用改良硫酸铵盐析法从鸡胆汁中分离鸡分泌型免疫球蛋白A(S IgA),M acro-prep H igh Q阴离子交换柱层析提纯,经二次过柱后获得的鸡S IgA浓度达22 m g/mL。SDS聚-丙烯酰胺凝胶电泳检测表明,重链分子质量为63~64 ku,轻链为26~28 ku,J链约16 ku。用纯化的鸡S IgA免疫兔,所得的抗血清经双向琼脂扩散,证明兔抗鸡S IgA血清效价达1¨128。     

无机离子的毛细管电泳分析及其在土壤上的应用

毛细管电泳用于溶液中无机离子的分析具有分离性能高、分离速度快、分析费用低、操作简单等优点,但精确性稍低。通过各种校准方法可部分地克服这一缺点。毛细管电泳极高的分离性能和极快的分离速度使土壤养分快速以至准实时分析成为可能,但其在土壤无机离子分析上的研究仍显不足,目前需要解决的问题之一是提高样品的前处理速度及对磷的提取能力。这些问题的解决将有利于提高土壤养分分析效率,促进毛细管电泳法在土壤养分分析方面的应用。