Probing Free Radical Damage to Biological Molecules by Spin-labeling Fluorophore

A spin-labeling fluorophore(NA-TEMPO ·), formed by labeling α-naphthalene with a paramagnetic nitroxide(4-hydroxyl-2,2,6,6-tetramethylpiperidinyl-1-oxy), was explored for biologically relevant carbon-centered radicals. The horseradish peroxidase (HPR)/H 2O 2 reaction was used to generate radicals in derivatives of tyrosine and phenylalanine, and the Fenton reaction was used to generate radicals in deoxyguanosine, guanosine, bovine serum albumin(BSA) and DNA. TEMPO ·-NA, a weak fluorescent compound, showed a dramatic increase in fluorescence intensity after scavenging carbon-centered radicals. The spin-labeling fluorophore with dual function groups, the radical recognizing group and fluorescent group, would be significantly useful in monitoring the formation and translocation of carbon-centered radicals in complex biological systems.国家自然科学基金 (批准号 :2 0 3 75 0 3 2 )资

Probing free radical damage to biological molecules by spin-labeling fluorophore

A spin-labeling fluorophore(NA-TEMPO.), formed by labeling a-naphthalene with a paramagnetic nitroxide (4-hydroxyl-2, 2, 6, 6-tetramethylpiperidinyl-1-oxy), was explored for biologically relevant carbon-centered radicals. The horseradish peroxidase (HPR)/H2O2 reaction was used to generate radicals in derivatives of tyrosine and phenylalanine, and the Fenton reaction was used to generate radicals in deoxyguanosine, guanosine, bovine serum albumin (BSA) and DNA. TEMPO.-NA, a weak fluorescent compound, showed a dramatic increase in fluorescence intensity after scavenging carbon-centered radicals. The spin-labeling fluorophore with dual function groups, the radical recognizing group and fluorescent group, would be significantly useful in monitoring the formation and translocation of carbon-centered radicals in complex biological systems

两种不同相对分子质量的壳寡糖对小鼠免疫功能的影响

目的研究两种不同相对分子质量的壳寡糖（chitosan oligosaccharide,COS）对小鼠免疫功能的影响。方法小鼠腹腔注射壳寡糖S-COS（平均相对分子质量800）,壳寡糖B-COS（平均相对分子质量1700）,硫酸岩藻糖（Fucoidan）120mg.kg-1,每日1次,连续14d,第10天注射5%牛血清白蛋白（bovine serum albumin,BSA）200μL/只进行免疫。于第15天检测脾指数,血清中细胞因子（IL-10、TNF-α、IFN-γ）含量,脾中淋巴细胞增殖,以及脾中CD4＋T细胞增殖。结果 S-COS和B-COS都能够促进CD4＋T细胞增殖,另外,B-COS还能增加脾指数,促进细胞因子IL-10和TNF-α分泌,以及脾中淋巴细胞增殖,而S-COS和硫酸岩藻糖则不能。结论 B-COS对小鼠免疫功能的调节作用优于S-COS

福岛核事故泄漏的大气放射性核素监测及其对西安地区的影响

2011年3月日本福岛核电站受海啸冲击后发生了严重核事故,并造成放射性核素的大量泄漏.事故发生后,在西安开展了3个月的大气放射性核素监测,获得了131I,134Cs,137Cs和133Xe等核素的浓度数据,并结合切尔诺贝利核事故后西安的监测数据及其他国家和地区的监测数据对本次监测结果进行了讨论,分析了泄漏核素到达西安的可能路径.从传输路径分析来看,福岛泄漏核素的扩散主要受西风影响,但在太平洋局部出现的反气旋和源项的连续释放特点,使泄漏核素到达中国的大气传输路径比较复杂.</p