细菌(Pseudomonas maltophilia)之绒毛膜促性腺激素(hCG)结合物质之研究

 细菌(Pseudomonas moltophilia)与hCG及LH有特异的亲和力,实验发现,细菌之生长曲线与hCG结合活性成平行关系,96小时达高峰,细菌之培养液中含有可溶性结合蛋白,该蛋白经硫酸铵沉淀(80％饱和度)、Sephadex G-100柱层析、DEAE-纤维素柱0.5mol/L NaCl梯度洗脱,再过Sepharose CL-AB柱,收集之活性部分经SDS电泳测得其分子量为70,000,凝胶层析测Stokes radius为41A,Schiff氏染色未见着色带。     

Molecular aptamer beacons for real-time protein recognition

One of the most pressing problems facing those attempting to understand the regulation of gene expression and translation is the necessity to monitor protein production in a variety of metabolic states. Thus far, there is no easy solution that will either identify or quantitate proteins in real time. Here we introduce a novel protein probe, molecular aptamer beacon (MAB), for real time protein recognition and quantitative analysis. The MAB combines the signal transduction mechanism of molecular beacons and the molecular recognition specificity of aptamers. An MAB based on a thrombin-binding aptamer was prepared as a model to demonstrate the feasibility. Significant fluorescent signal change was observed when MAB was bound to thrombin, which is attributed to a significant conformational change in MAB from a loose random coil to a compact unimolecular quadruplex. The MAB recognizes its target protein with high specificity and high sensitivity (112 picomolar thrombin concentration) in homogeneous solutions. Ratiometric imaging has been conducted with MAB labeled with two fluorophores, which makes it feasible for protein quantitation in living specimen. The unique properties of the MAB will enable the development of a class of protein probes for real time protein tracing in living specimen and for efficient biomedical diagnosis in homogeneous solutions.     

Cyclosporine A enhances leukocyte binding by human intestinal microvascular endothelial cells through inhibition of p38 MAPK and iNOS. Paradoxical proinflammatory effect on the microvascular endothelium

The calcineurin inhibitor cyclosporine A (CsA) modulates leukocyte cytokine production but may also effect nonimmune cells, including microvascular endothelial cells, which regulate the inflammatory process through leukocyte recruitment. We hypothesized that CsA would promote a proinflammatory phenotype in human intestinal microvascular endothelial cells (HIMEC), by inhibiting inducible nitric-oxide synthase (iNOS, NOS2)-derived NO, normally an important mechanism in limiting endothelial activation and leukocyte adhesion. Primary cultures of HIMEC were used to assess CsA effects on endothelial activation, leukocyte interaction, and the expression of iNOS as well as cell adhesion molecules. CsA significantly increased leukocyte binding to activated HIMEC, but paradoxically decreased endothelial expression of cell adhesion molecules (E-selectin, intercellular adhesion molecule 1, and vascular cell adhesion molecule-1). In contrast, CsA completely inhibited the expression of iNOS in tumor necrosis factor-alpha/lipopolysaccharide-activated HIMEC. CsA blocked p38 MAPK phosphorylation in activated HIMEC, a key pathway in iNOS expression, but failed to inhibit NFkappaB activation. These studies demonstrate that CsA exerts a proinflammatory effect on HIMEC by blocking iNOS expression. CsA exerts a proinflammatory effect on the microvascular endothelium, and this drug-induced endothelial dysfunction may help explain its lack of efficacy in the long-term treatment of chronically active inflammatory bowel disease.     

Studies on the phospholipid composition of pathogenic cell membranes of Mycoplasma hyopneumoniae

The membrane phospholipid and fatty acid compositions of Mycoplasma hyopneumoniae, a pathogen of porcine enzootic pneumoniae isolated in China, was studied by thin-layer chromatography and gas chromatography. The results showed that membrane phospholipids consisted predominantly of diphosphatidylglycerol. The percentage of C16 - C18 fatty acids comprised 79% of the total fatty acids, of which oleic acid as well as palmitic acid are the major fatty acids. Some differences were shown in fatty acid composition as compared with membranes of other species of Mycoplasma.     

体温对沙鼠前脑缺血/再灌注Ca~(2 )/钙调素依赖性蛋白激酶Ⅱ活性变化的影响

目的和方法 :本文以蒙古沙土鼠双侧颈动脉夹闭 (BCAO)形成前脑缺血模型 ,观察不同体温 (3 6.5℃、3 0 .0℃、3 9.0℃ )对脑缺血 /再灌注海马、皮质、纹状体、小脑Ca2 /CaMPKⅡ活性变化的影响。结果 :①除小脑外 ,海马、皮质、纹状体Ca2 /CaMPKⅡ活性在缺血后均有不同程度下降 ,该下降对缺血过程中体温变化十分敏感 :如分别于 3 6.5℃、3 0 .0℃、3 9.0℃时同样缺血 10min ,海马酶活性分别为对照组的 3 2 .2 %、10 1.3 %、9.1% ;②持续一定时间的低体温再灌注可显著促进海马、皮质、纹状体该酶活性的恢复 :如 3 6.5℃和 3 0 .0℃再灌注相同时间后 ,海马酶活性分别为对照组的 5 1.3 %和 5 3 .2 % (4h ,P >0 .0 5 )、5 8.0 %和 68.9% (8h ,P <0 .0 5 )、67.4 %和 84 .1% (16h ,P <0 .0 5 )。结论 :低体温可显著保护脑缺血 /再灌注缺血敏感组织Ca2 /CaMPKⅡ活性 ,这可能与其保护缺血性脑损伤关系密切。     

海南岛翼手目物种多样性现状与分布预测

海南岛位于我国南部, 地处热带北缘, 其独特的岛屿气候环境孕育了丰富的生物资源, 为我国生物多样性热点地区之一。为探究岛内的翼手目物种多样性状况, 本研究组使用雾网、蝙蝠竖琴网等工具, 于2002年至2016年先后对海南岛进行了15次翼手目多样性调查, 并根据其外形与头骨特征及系统发育学方法进行标本鉴定。共获取了1,025号标本, 隶属5科15属31种, 其中2016年12月21日在海南琼中捕获的艾氏管鼻蝠(Murina eleryi)为海南岛蝙蝠分布新记录。结合前人调查及发表结果统计, 岛内共有翼手类8科20属41种。同时基于本调查采集位点和前人调查位置信息(共计363个位点), 结合WorldClim 32种气候数据, 运用最大熵模型(MaxEnt)对海南岛翼手目物种的分布进行预测, 结果显示五指山、吊罗山、鹦哥岭、尖峰岭及海口火山口国家地质公园等地为翼手目物种多样性较丰富的区域, 而三亚、澄迈、屯昌、临高、琼海等地翼手目物种多样性较低。本研究结果为海南岛翼手目资源分布及多样性状况提供了基础资料, 也为岛内后续开展翼手目资源保护管理、蝙蝠疾病防控等提供了重要的参考依据。     

Daily rhythm and seasonal pattern of lick use in sika deer (Cervus nippon) in China

Many ungulates are reported to use natural or artificial licks with seasonal patterns around the world. From December 2016 to August 2017, we used infrared camera to record the use of artificial licks in wild sika deer (Cervus nippon) in Zhejiang Qingliangfeng National Nature Reserve, China. We explored the daily rhythm, seasonal pattern and sex difference in lick utilization. In total, 12,043 videos and 22,901 pictures were collected. Our results showed that: (1) the lick visiting frequency was higher at night than that during daytime; (2) the difference in lick visiting frequency between females and males disappeared after taking into account of sex ratio; (3) the lick duration peaked in April during a year. These findings suggested that there were clear daily rhythm and seasonal pattern of lick use in sika deer. Seasonal change in lick use intensity was consistent with our prediction. These variations in lick use might be driven by both the physiological needs of the mineral elements in different life stages and the seasonal changes in climate and food. The reserve management authority should pay more attention to the supplement of licks in spring and summer to fulfill animal’s physiological needs.