呼伦贝尔草原冬季狼的巢域和生境利用

2004年冬季,在内蒙古呼伦贝尔市达赉湖自然保护区对狼的家域和生境利用状况进行了调查。通过跟踪狼的雪地(或沙地)足迹,记录狼的活动情况和家域标记点(尿或粪等)的地理坐标,运用最小凸多边形法计算狼的家域。结果显示达赉湖地区狼的家域为112km2。在狼的巢域内,狼的洞穴主要选择芦苇草原生境,选择率为95.45%。捕食生境主要为牧民点,选择率为57.14%。     

环氧二十碳三烯酸生物学作用机制的研究进展

花生四烯酸经过细胞色素P450 (cytochrome P450,CYP)表氧化酶途径生成环氧二十碳三烯酸(epoxyeicosatrienoic acids,EETs)。EETs可以通过调节离子通道和基因表达,从而发挥促进血管舒张、抗炎和细胞增殖等作用。EETs也可通过激活信号转导途径和调节基因表达或与细胞膜受体结合发挥多种生物学功能。EETs也可快速与细胞膜磷脂结合后以共吸收的方式被细胞摄取。文章主要从EETs的来源、去路、作用机制等方面进行讨论。     

可溶性环氧化物水解酶抑制剂的降血糖功效研究

为探究可溶性环氧化物水解酶抑制剂（soluble epoxide hydrolase inhibitors,sEHI）的降血糖功效,试验以高脂饲料与链脲佐菌素（streptozotocin,STZ）联合诱导的Ⅱ型糖尿病小鼠为研究对象,将C57BL/6J小鼠随机分为：正常对照组、糖尿病模型组和sEHI组,sEHI组饲喂高脂饲料,每日灌胃sEHI （t-AUCB）1 mg/kg,连续灌胃4周;糖尿病模型组饲喂高脂饲料,每日灌胃同等计量的生理盐水;正常对照组饲喂普通饲料,每日灌胃同等体积的生理盐水。期间各组小鼠均自由采食及饮水,记录小鼠体重、血糖并进行口服葡萄糖耐量试验。试验结束后,测定血清血脂指标、肝脏过氧化指标并对小鼠胰岛组织进行病理学分析。结果显示,与糖尿病模型组相比,采用sEHI干预后糖尿病小鼠的空腹血糖显著降低（P<0.05）,而葡萄糖耐量水平升高;小鼠血清总胆固醇（TC）、甘油三酯（TG）、低密度脂蛋白（LDL）水平明显降低,其中TC、TG水平与糖尿病模型组相比差异显著（P<0.05）,而高密度脂蛋白与胆固醇比值（HDL/TC）水平则显著升高（P<0.05）;与糖尿病模型组相比,sEHI干预组小鼠肝脏的超氧化物歧化酶（SOD）、过氧化氢酶（CAT）活性显著提高（P<0.05）,丙二醛（MDA）活性显著降低（P<0.05）;小鼠的胰岛组织切片分析结果表明,sEHI对小鼠胰岛组织有明显的修复作用。综上所述,sEHI具有降血糖、减轻自由基损伤、抑制脂质过氧化、修复受损胰岛组织的作用。     

宏基因组学及其应用前景

Metagenomics is the study of communities of microbial organisms directly in their natural environments, bypassing the need for isolation and laboratory cultivation of individual species and showing strong vitality in research of the metabolic pathway and exploring the resource of rumen microbiota. There are abundance of symbiotic microbiota in the gastrointestinal tract of animals, and they are deeply associated with the well-being of the host because of affecting normal physiology, metabolism and health, as well as the development of diseases. The application of metagenomics may solve many hot and difficult issues in the research of ruminant metabolism, especially camel metabolism. Therefore, this paper reviews the construction and selection procedures, especially introduced the Roche454 and Illumina high-throughput sequencing methods. Meanwhile, the application prospects of metagenomic in communities of microbial organisms are explored.     

Purification and quantification of heavy‐chain antibodies from the milk of bactrian camels

Camel milk has a unique composition with naturally occurring heavy‐chain antibodies (HCAbs), which exert rehabilitating potencies in infection and immunity. To characterize HCAb in camel milk, immunoglobulin G (IgG) was isolated from the milk of Camelus bactrianus by a combination of affinity chromatography and sodium dodecyl sulfate polyacrylamide gel electrophoresis to purify and size‐fractionate protein A and protein G, which were further identified by Western blotting, and were quantified by bicinchoninic acid (BCA) and ELISA. The results indicated that IgG₁ fraction contains molecules of 50 kDa heavy chains and 36 kDa light chains. The HCAbs (IgG₂ and IgG₃ fractions) devoid of light chains, contain heavy chains of 45 kDa and 43 kDa, respectively, the amounts of which were significantly higher than that of the IgG₁ in the milk of bactrian camels. Above all, we revealed the considerable amounts of HCAbs in the milk of bactrian camels, and developed a novel method for their purification and quantification. These findings provide the basis for developing potential effects of camel milk and its interface with the dairy industry, as well as future investigations of HCAb and its roles in human health and diseases.     

Hypoglycemic Effect of Soluble Epoxide Hydrolase Inhibitors on Diabetic Mice

In order to study the hypoglycemic effect of soluble epoxide hydrolase inhibitors (sEHI) on diabetic mice,the diabetic mice model were successfully induced by high-fat diet and streptozotocin (STZ). The diabetic mice (C57BL/6J) were randomly divided into three groups,including normal control group,diabetic control group and sEHI group,the mice in three groups were fed high-fat diet+1 mg/kg sEHI (t-AUCB),high-fat diet+same volume normal saline,normal diet+same volume normal saline,respectively,and intervention last for 4 weeks. During the experiment,the body weight,blood glucose were recorded,and performed oral glucose tolerance test was conducted. After the experiment,indicators of serum lipids,liver peroxidation and pathological analysis of pancreatic tissue were measured. The results showed that compared with diabetic control group,the fasting blood glucose of mice in sEHI group was significantly reduced (P<0.05),and their glucose tolerance was improved. And the TC (P<0.05),TG (P<0.05) and LDL (P>0.05) in sEHI group were decreased,while the LDL/TC was significantly increased (P<0.05).The SOD and CAT activity in liver of diabetic mice treated with sEHI were significantly increased (P<0.05) and MDA activity was significantly decreased (P<0.05).Based on mouse pancreatic tissue sections,we speculated that sEHI had ability to repair activity on damaged islet tissue. In conclusion,the sEHI could reduce the blood glucose level and the free radical damage,inhibit lipid peroxidation,repair of damaged islet tissue in mice.