荧光法研究3种黄酮化合物与牛血清白蛋白的结合作用

运用荧光光谱法研究了生理酸度条件下（pH=7.4）3种黄酮化合物白杨素、芹菜素和桑色素与牛血清白蛋白（BSA）的结合作用。结果表明,3种黄酮化合物均能与BSA形成基态复合物导致BSA内源荧光猝灭,猝灭机理为静态猝灭。结合常数K（芹菜素）〉K（白杨素）〉K（桑色素）,结合位点数近似等于1,白杨素与BSA之间以疏水作用为主,而芹菜素、桑色素与BSA之间的作用力主要是氢键和范德华力。黄酮分子结构中羟基位置及个数影响其与BSA间的结合作用,C4＇-OH对结合有促进作用,而C3-OH的取代则导致作用力减弱。由Frster非辐射能量转移理论,计算出3种黄酮化合物在蛋白质中的结合位置与212位色氨酸残基间的距离分别为2.44 nm（白杨素）、3.34 nm（芹菜素）和3.31 nm（桑色素）。     

人血清淀粉样蛋白A1原核表达及胶体金检测方法的建立

通过胶体金免疫层析技术建立一种特异、便捷、快速的SAA1定量检测新方法.利用大肠杆菌BL21(DE3)原核表达人血清淀粉样蛋白A1(SAA1),根据BL21(DE3)表达偏好性设计并合成SAA1蛋白基因片段,构建表达载体pET-28a-SAA1,采用CaCl2法制备BL21(DE3)感受态,热激转化法将pET-28a-SAA1转入到BL21(DE3).经表达条件优化,获得重组蛋白最佳诱导表达条件:温度30℃,时间6h,转速180rpm/min,培养基pH 7.0,IPTG浓度0.4mM,诱导表达后目的蛋白经SDS-PAGE电泳鉴定,Ni柱纯化、透析、浓缩从而获得浓度为8.09mg/ml,纯度为85%的SAA1.同时,结合胶体金标记技术,建立了SAA1胶体金免疫层析试纸检测方法,线性范围0.16~500μg/ml,最低检测限0.16μg/ml,该研究为临床体外诊断SAA1快速检测提供技术基础.     

Factors associated with serum magnesium and vascular stiffness in maintenance hemodialysis patients

Introduction : We evaluated the associated factors of serum magnesium in patients on maintenance hemodialysis (MHD). Furthermore, we evaluated the relationship between low serum magnesium and arteriosclerosis in these patients. Methods : In 129 patients on MHD, we evaluated the blood levels of magnesium, brachial‐ankle pulse wave velocity (ba‐PWV), ankle‐brachial index (ABI), and intima‐media thickness of the common carotid artery (IMT). Findings : In MHD patients, the serum level of magnesium was significantly correlated with age, calcium, TNF‐α, albumin, and ba‐PWV but not with ABI or IMT. In the multiple regression analysis, albumin (P = 0.0001, β = 0.31) and calcium (P = 0.029, β = 0.18) were selected as significant predictors of the magnesium level in MHD patients. Furthermore, the serum level of magnesium, as well as systolic blood pressure (P = 0.0001, β = 0.32) and age (P = 0.005, β = 0.25), were selected as significant (P = 0.012, β = ?0.22) predictors of ba‐PWV in MHD patients. Discussion : In MHD patients, the serum magnesium level was associated with the serum levels of calcium and albumin. Furthermore, a low serum magnesium level in MHD patients was associated with the index of vascular stiffness.     

不同品系北京鸭血清前白蛋白多态性的研究

应用聚丙烯酰胺凝胶电泳法研究了北京鸭的血清前白蛋多态性,在2个位点观察到多态,Pam位点为单态,在Pas位点发现有5种表现型,它们的频率是：Pas2-2O 26．67％,Pas1-2为12％,Pas2-1为45.33%,Pas1-1为2．67％,Pas2-0为13．33％,在Paf位点发现有4种表现型,它们的频率是：PafF为29．33％,PafS为41．33％,PafFS为10．67％,Paf0为18．67％,并计算了它们的基因频率,群体平均杂合度和遗传距离,遗传分析表明,樱桃谷鸭和奥白星鸭遗传结构相似,而与B系北京鸭遗传结构有明显差异。     

抗狂犬病血清致过敏反应及血清病的探讨

128例犬咬伤患者注射抗狂犬病血清后,过敏反应发生率为3.91％(5/128);血清病发生率为11.72％(15/128)。过敏反应的主要症状为头晕、恶心、面色苍白;血清病的主要症状为局部及周身荨麻疹、表浅淋巴结肿大、恶心、食欲不振等。血清病有明显的年龄特点,0～19岁儿童和青少年发生率为4.0％,20岁以上成年人为13.59％,二者差异显著。     

压电式传感器测定蛋白质吸附动力学参数

利用液隔电极型压电式传感器实时监测牛血清白蛋白(BSA)在石英表面吸附过程。基于所提出的吸附动力学模型,估算出BSA在石英表面的吸附速率常数为ka=1.27×103mol-1·L·s-1,脱附速率常数为kd=1.31×10-3s-1,由可逆吸附态向不可逆吸附态的转化速率常数为kf=3.46×10-4s-1。     

磁场对大鼠血清营养相关生化指标的影响

报道了旋转恒定磁场对大鼠血液生化指标的影响.在强度为0 4T,旋转速率为8Hz的磁场条件下,鼠龄3周的大鼠,磁场每天处理2h,共持续10周,导致血清葡萄糖水平显著下降;鼠龄为10周的大鼠,每天磁场处理2h,共持续4周,则引起血清甘油三酯水平的显著降低,血清高密度脂蛋白水平则显著上升.     

豆浆污染管式膜清洗系统的实验研究

开发海绵橡胶球(固)-水(液)两相清洗系统，用于豆浆污染的管式膜的清洗．通过海绵橡胶球清洗与传统大量水冲清洗方法对水通量恢复率和蛋清截留率的比较，确认了前者具有良好的清洗效果．前者恢复率比后者高约10％，蛋清截留率基本不受影响，对膜孔径无明显影响．     

血竭总黄酮与血清白蛋白的作用

应用荧光光谱法研究不同离子强度、温度、酸度条件下,血竭总黄酮(tFSD)与血清白蛋白的相互作用。研究表明:tFSD能不同程度地猝灭牛血清白蛋白(BSA)和人血清白蛋白(HSA)的荧光强度,BSA的荧光强度猝灭得更显著;在288~298K间,随着温度的升高,BSA-tFSD和HSA-tFSD两荧光体系的猝灭程度降低,推测tFSD对BSA、HSA的荧光猝灭作用不是动态猝灭,而是静态猝灭;在pH6.0~pH10.0间,随着pH的提高,tFSD对BSA(HSA)的荧光猝灭程度上升,说明tFSD与BSA(HSA)之间以非静电作用为主,并形成了不发荧光的复合物。     

Impact of Freeze-Drying on Cord Blood (CB), Serum (S), and Platelet-Rich Plasma (CB-PRP) Preparations on Growth Factor Content and In Vitro Cell Wound Healing

Blood-based preparations are used in clinical practice for the treatment of several eye disorders. The aim of this study is to analyze the effect of freeze-drying blood-based preparations on the levels of growth factors and wound healing behaviors in an in vitro model. Platelet-rich plasma (PRP) and serum (S) preparations from the same Cord Blood (CB) sample, prepared in both fresh frozen (FF) and freeze-dried (FD) forms (and then reconstituted), were analyzed for EGF and BDNF content (ELISA Quantikine kit). The human MIO-M1 glial cell line (Moorfield/Institute of Ophthalmology, London, UK) was incubated with FF and FD products and evaluated for cell migration with scratch-induced wounding (IncuCyte S3 Essen BioScience), proliferation with cyclin A2 and D1 gene expression, and activation with vimentin and GFAP gene expression. The FF and FD forms showed similar concentrations of EGF and BDNF in both the S and PRP preparations. The wound healing assay showed no significant difference between the FF and FD forms for both S and PRP. Additionally, cell migration, proliferation, and activation did not appear to change in the FD forms compared to the FF ones. Our study showed that reconstituted FD products maintained the growth factor concentrations and biological properties of FF products and could be used as a functional treatment option.