来自于变性链球菌的脱氧胞嘧啶核苷酸脱氨酶的表达，纯化，结晶以及初步晶体学研究

脱氧胞嘧啶核苷酸脱氨酶属于脱氧胞苷酸脱氨家族.对来自于变性链球菌UA159的脱氧胞嘧啶核苷酸脱氨酶进行了克隆,在大肠杆菌中进行了表达,最后纯化.快速液相分子排阻色谱分析表明这种酶在溶液中形成六聚体.利用悬滴气相扩散技术获得了这个蛋白的晶体.在北京同步辐射的3W1A线站,收集了衍射分辨率到达3.1!的数据.这个晶体属于P213空间群,其晶胞参数为a=b=c=113.2",!="=#=90°.计算可得马修斯系数为3.6#3·Da-1,据此可估计在一个不对称单位中含有两个单亚基.据目前所知,这是第一个关于野生型的脱氧胞嘧啶核苷酸脱氨酶的结晶学报道.     

大熊猫精清血小板激活因子乙酰水解酶(PAF-AH)活性影响因素的初步探讨

在2004年度2~5月大熊猫繁殖季节,对5只不同年龄雄性大熊猫的精液使用酶免法检测精清中的PAF-AH含量,并初步探讨了其含量高低的影响因素。结果在所有受检样品中均检测到PAF-AH活性的存在,浓度最低仅12.96 mmol/min.mL,最高达275.42 mmol/min.mL,大熊猫年龄不同、采精时间不同,精清PAF-AH含量存在一定差异;同时PAF-AH的含量表现出与精子活力呈极显著负相关(R=-0.73,P<0.001),与精子运动状态呈显著负相关(R=-0.58,P<0.05);与精子形态完整性也有一定相关性但差异不显著(R=-0.42,P>0.05)。结果表明,大熊猫精清中含有PAF-AH,其含量高低与大熊猫年龄、采精季节及精液质量有关。     

茴香薄翅野螟发生动态的调查

经调查研究表明:在青海省的油菜种植区,茴香薄翅野螟Evergestis extimalis Scopoli越冬幼虫从6月初开始化蛹,6月中旬化蛹率达为80%,到6月下旬化蛹率达到100%;成虫于7月上旬开始羽化,7月15～20日为成虫羽化高峰;田间卵始见期为6月下旬至7月上旬,7月中旬达到产卵高峰期;越冬幼虫平均死亡率为96.63%。     

Characterization of multivalent lactose quantum dots and its application in carbohydrate–protein interactions study and cell imaging

We have previously reported a facile and convenient method for the preparation of a new type of lactose-CdSeS/ZnS quantum dots conjugates (Lac-QDs) that exhibit biocompatibility, noncytotoxicity and specificity to leukocytes. In order to further study the carbohydrate–protein interactions, a series of Lac-QDs with different lactose densities and a PEGylated (n = 3) lactose-QDs conjugate (LacPEG-QDs) with more flexible sugar ligands were prepared. The amount of the sugar molecules on QDs can be determined by NMR, which was in agreement with the results from TGA determination. The formula of the conjugates was determined with ICP-OES. The interactions between the conjugated QDs and the PNA protein were measured using SPR, which revealed that higher lactose density favored binding affinity under the same concentration, and Lac-QDs exhibit higher affinity than LacPEG-QDs. We further used a solid phase assay to assess the anti-adhesion activity of Lac-QDs and LacPEG-QDs on the cell level. The results showed that Lac-QDs had stronger activity in preventing THP1 from adhering to HUVEC than LacPEG-QDs, which was consistent with the SPR results. We reasoned that decrease in the conformational entropy induced by appropriate restriction of sugar flexibility could enhance the binding affinity of glyco-QDs, which implies that entropy change may be the main contributor to the interaction between high valent glyco-QDs and protein. The fabrication of lactose on QDs provides a fluorescent multivalent carbohydrate probe that can be used as mimics of glycoprotein for the study of carbohydrate–protein interactions and cell imaging.     

驻某地武警机关干部体质指数与代谢性疾病的关系

目的:探讨健康体检的驻某地武警机关干部体质指数(BMI)与代谢性疾病的关系。方法:采用横断面调查方法对健康体检的1920名驻某地武警机关干部和270名地方机关干部的体质指数情况进行比较分析,探讨超重肥胖与代谢性疾病的关系。结果:1.军人组超重率及肥胖率均低于地方组(P<0.01)。2.<50岁人群组随年龄增加,超重及肥胖检出率有增高趋势(P<0.01),40~49岁人群超重率和肥胖率最高;50~65岁人群超重与肥胖率最低。3.两组机关干部随BMI升高,高总胆固醇、高甘油三酯、高尿酸血症、脂肪肝检出率增高(P<0.01);军人组高尿酸血症发病率明显高于地方组(P<0.05);高血压、高血脂发病率明显降低(P<0.05);与地方超重组比较,军人超重组脂肪肝发病率明显升高(P<0.05)。4.在30~50岁的军人中,随着年龄升高,高血压、高血糖、高血脂、高尿酸,脂肪肝发病率明显升高(P<0.01)。结论:健康体检人群超重、肥胖率较高,控制体重对高血压、高血糖、高血脂及脂肪肝等慢性病的防治具有重要意义。军人组超重与肥胖率均低于地方,但高尿酸血症和高脂肪肝发病率升高,故建议有代谢性疾病的军人限制饮酒可能会受益。     

人Neuritin在原核表达系统的构建及表达纯化

Neuritin是一种新发现能促进神经突起和轴突分支的蛋白,为了更清楚的研究它的生物学功能,我们在已克隆Neuritin cDNA的基础上, PCR扩增出Neuritin ORF,与原核表达载体pET32a重组后,成功的构建了Neuritin原核表达质粒pET32a-Neuritin。重组质粒转化BL21大肠杆菌, IPTG诱导后,表达产物用SDS-PAGE 和Western blot证实系Neuritin,用镍离子亲和层析的方法获得了纯化的Neuritin蛋白。     

锐孔菌属一新种

本文报道了多孔菌科(Polyporaceae)锐孔菌属(Oxyporus)一新种:长白锐孔菌(Oxyporus changbaiensis Y.P.Bai et X.L.Zeng)。本种在形态特征上与黄白锐孔菌[Oxy-porus cervino-gilvus(Jungh.)Ryv.]相近,但菌丝具有大量横隔膜,且孢子较宽;亦与宽边锐孔菌[Oxyporus latemaginatus(Dur.et Mont.)Donk]相似,但孢子较大,有时有菌盖,囊状体上部被以结晶。文中有拉丁文及中文描述。     

Expression of mutant huntingtin in glial cells contributes to neuronal excitotoxicity

Huntington disease (HD) is characterized by the preferential loss of striatal medium-sized spiny neurons (MSNs) in the brain. Because MSNs receive abundant glutamatergic input, their vulnerability to excitotoxicity may be largely influenced by the capacity of glial cells to remove extracellular glutamate. However, little is known about the role of glia in HD neuropathology. Here, we report that mutant huntingtin accumulates in glial nuclei in HD brains and decreases the expression of glutamate transporters. As a result, mutant huntingtin (htt) reduces glutamate uptake in cultured astrocytes and HD mouse brains. In a neuron-glia coculture system, wild-type glial cells protected neurons against mutant htt-mediated neurotoxicity, whereas glial cells expressing mutant htt increased neuronal vulnerability. Mutant htt in cultured astrocytes decreased their protection of neurons against glutamate excitotoxicity. These findings suggest that decreased glutamate uptake caused by glial mutant htt may critically contribute to neuronal excitotoxicity in HD.     

深圳无偿献血人群中李姓、王姓和张姓无关男性个体Y-STR单倍型遗传多态性

为研究姓氏群体Y染色体特异STR单倍型的遗传多态性, 采用PCR复合扩增和ABI PrismTM 3100基因测序仪荧光检测方法对DYS426等9个Y-STR基因座进行基因分型, 检测深圳地区李姓无关男性个体血样139份、王姓无关男性个体118份、张姓无关男性个体119份。结果在139份李姓群体中, 共检出126种单倍型, 其中118种单倍型仅出现1次, 检出频率最高的1种单倍型出现6次, 单倍型多样性为0.9974; 118份王姓无关男性样本中, 共检出105种单倍型, 其中94种单倍型仅出现1次, 检出频率最高的1种单倍型出现4次, 单倍型多样性为0.9953; 张姓无关男性样本中, 共检出101种单倍型, 其中88种单倍型仅出现1次, 检出频率最高的1种单倍型出现4次, 单倍型多样性为0.9964。结果表明: 深圳地区李、王、张姓氏无关男性个体Y-STR单倍型的遗传多态性丰富, 与以往的汉族无关男性群体遗传资料相比较, 差异不显著。