肝素浓度和作用时间对绵羊精子体外获能和体外受精的影响

摘 要：通过研究添加不同的肝素浓度(0、5、10、20、50μg/ml)及不同作用时间（0、30、45、60、90、120min）对绵羊精子体外获能、存活时间和相应体外受精的影响,为改善绵羊精子体外获能效果及研究获能的机理提供一定的参考。在获能液中添加10μg/ml肝素作用45min时,其获能率最高,顶体反应率最低（40.92％和16.59％）（P<0.05）,存活时间18h,能够提高受精卵的囊胚发育;单独使用咖啡因或与10μg/ml肝素联合使用,其获能效果均不如单独使用10μg/ml肝素。说明绵羊精子获能时肝素的适宜浓度是10μg/ml,作用时间是45min,咖啡因无协同肝素促进获能的作用。     

Glycosaminoglycans from Litopenaeus vannamei Inhibit the Alzheimer’s Disease β Secretase,BACE1

Only palliative therapeutic options exist for the treatment of Alzheimer’s Disease; no new successful drug candidates have been developed in over 15 years. The widely used clinical anticoagulant heparin has been reported to exert beneficial effects through multiple pathophysiological pathways involved in the aetiology of Alzheimer’s Disease, for example, amyloid peptide production and clearance, tau phosphorylation, inflammation and oxidative stress. Despite the therapeutic potential of heparin as a multi-target drug for Alzheimer’s disease, the repurposing of pharmaceutical heparin is proscribed owing to the potent anticoagulant activity of this drug. Here, a heterogenous non-anticoagulant glycosaminoglycan extract, obtained from the shrimp Litopenaeus vannamei, was found to inhibit the key neuronal β-secretase, BACE1, displaying a more favorable therapeutic ratio compared to pharmaceutical heparin when anticoagulant activity is considered.     

化脓隐秘杆菌肝素结合蛋白的提取及铁结合蛋白的黏附特性分析

肝素可剂量依赖性地抑制化脓隐秘杆菌(Trueperella pyogenes)黏附宿主细胞.本研究旨在认识化脓隐秘杆菌肝素结合蛋白及其黏附特性,采用肝素琼脂糖凝胶从化脓隐秘杆菌裂解物中提取蛋白,运用蛋白质质谱和免疫印迹对所提取的蛋白质进行鉴定.采用免疫印迹检测所提取蛋白质与自然感染化脓隐秘杆菌山羊血清的反应原性.制备重...     

咖啡因和肝素、钙离子载体对家畜冷冻精子体外获能的协同作用

本文报道了用咖啡因与肝素、钙离子载体(I-A)协同处理诱导马、驴、猪冷冻精子体外获能的研究结果.咖啡因与肝素、I-A均有协同作用.在肝素或I-A处理中添加咖啡因,不仅能提高穿透率,而且能促进卵内雄原核的形成和发育.精子先经洗涤,再用咖啡因与肝素或I-A协同处理,可得到良好的获能效果.     

新生牛血中Cu/Zn-SOD的提纯及肝素、壳聚糖的逐层自组装包裹

试验旨在通过对超氧化物歧化酶（super oxide dismutase, SOD）改性,提高其稳定性。本试验采用了热变性提取方法从新生牛血中提取Cu/Zn-SOD,采用逐层自组装技术,以肝素与壳聚糖为材料,对从新生牛血中分离提纯的SOD进行物理包裹试验,并对包裹后Cu/Zn-SOD的稳定性进行研究。结果显示,在耐热稳定性上,包裹的SOD相对酶活性比天然SOD提高了3.3倍;在耐酸碱性方面,在pH分别为3.0、11.0的条件下,包裹的SOD相对酶活性较天然SOD提高了2.0倍;在抗胰蛋白酶水解的能力上,包裹的SOD相对酶活性较天然SOD提高了2.7倍。采用肝素、壳聚糖制成的外壳对SOD进行物理修饰可得到较好的效果,且其具有较强的机械强度、生物相容性较好,外表面的壳聚糖有助于帮助跨细胞膜转运,可应用于口服剂型SOD的开发。     

恶性疟原虫肝素结合蛋白质PF3D7_1104400的原核表达与多克隆抗体的制备

为研究肝素结合蛋白质PF3D7_1104400的功能以及其作为疟疾疫苗候选抗原的可行性,通过PCR方法扩增目的基因,并将其与p ET-28a和p GEX-4T-1表达载体连接构建重组表达质粒。将构建成功的重组表达质粒转化入大肠杆菌BL21-Condon Plus(DE3)-RIPL中诱导表达,利用亲和层析的方法纯化His-tag和GSTtag重组蛋白质。用His-tag重组蛋白质免疫家兔制备多克隆抗体,以该抗体为一抗,利用Western blot检测该抗体的特异性以及PF3D7_1104400蛋白质在虫体内是否表达。结果表明:成功构建重组表达质粒PF3D7_1104400-p ET和PF3D7_1104400-p GEX,诱导表达并纯化出特异性好、纯度高的重组蛋白。制备的多克隆抗体能够特异性识别虫体天然蛋白,PF3D7_1104400蛋白质在恶性疟原虫体内全长表达。     

蚓激酶对急性中危肺血栓栓塞患者治疗的临床疗效观察

目的 探讨蚓激酶对急性中危肺血栓栓塞患者治疗中的疗效及安全性。方法 选择2010年1月至2015年10月在我院住院治疗的60例急性中危肺血栓栓塞患者进行前瞻性队列研究,患者分为治疗组（蚓激酶联合低分子肝素钠序贯华法林组）30例和对照组（低分子肝素钠序贯华法林组）30例,根据不同时期两组各分为治疗前、治疗后10 d、治疗后20 d和治疗后30 d亚组。比较治疗前、治疗后10 d、20 d及30 d临床疗效及安全性。结果 超声心动图结果表明蚓激酶组右心室最大短轴直径、左心室最大短轴直径、右心室最大短轴与左心室最大短轴直径比值、肺动脉收缩压和主肺动脉直径值在治疗后10 d、20 d及30 d与对照组比较差异显著,且两组组间比较差异均有统计学意义（P<0.05）。与对照组比较,蚓激酶组NT-proBNP在治疗后10 d、20 d和30 d显著降低,而PaO₂值在治疗后10 d、20 d和30 d明显升高,且对照组和蚓激酶组各亚组组间的NT-proBNP和PaO₂值比较差异均有统计学意义（P<0.05）。D-二聚体在对照组和蚓激酶组治疗后10 d明显增高,而在治疗后20 d、30 d显著降低,且两组及组间比较差异均显著,具有统计学意义（P<0.05）。结论 蚓激酶联合低分子肝素钠序贯华法林治疗急性中危肺血栓栓塞患者临床疗效好且安全,值得临床推广应用。     

Low‐Molecular‐Weight Heparin Dosage in Newborn Foals

Background: Heparin is used in humans as prophylaxis of hypercoagulable states and disseminated intravascular coagulation (DIC). However, babies need a higher heparin dose than do adults. Septic neonate foals are at high risk of hypercoagulable state and DIC, and there is limited objective information about heparin dose for equine neonates. Objective: To assess whether neonate foals require higher dosages of low‐molecular‐weight heparin (LMWH) than adults. Animals: Eighteen healthy and 11 septic neonate foals. Methods: Experimental and clinical studies. Firstly, healthy foals were randomly distributed in 2 groups, 1 receiving 50 IU/kg SC of dalteparin and the 2nd group receiving 100 IU/kg SC of dalteparin, once daily for 3 days. Blood samples were collected before and 3, 6, 27, and 51 hours after the 1st LMWH administration. Plasma antifactor‐Xa activity was measured, together with hemostatic and hematologic parameters used to assess the risk of bleeding. Subsequently, septic foals were treated blindly either with placebo (saline) or 100 IU/kg of dalteparin for 3 days. Plasma antifactor‐Xa activity and other hemostatic parameters were determined before and after treatment. Results: Plasma antifactor‐Xa activity in healthy foals was below prophylactic activity when using the adult dosage (50 IU/kg), whereas prophylactic activities were achieved when using the double dosage (100 IU/kg). No hemorrhagic events and erythrocyte‐related complications were observed with either dosage. In the clinical study, only 4/6 septic foals had plasma antifactor‐Xa activity adequate for prophylaxis. Conclusions and Clinical Importance: Equine neonates require higher dosages of LMWH compared with adults to reach prophylactic heparinemia.     

Efficacy of low molecular weight heparin in a canine model of thromboplastin-induced acute disseminated intravascular coagulation

The aim of this study was to test the efficacy of different dosages of low molecular weight heparin (LMWH) in acute DIC which was induced in anaesthetised dogs by 4 h infusions of a canine lung thromboplastin extract. In all animals during the first 2 h, development of acute DIC was characterised by decreasing fibrinogen concentrations, platelet numbers, factor V- and antithrombin activities. Two hours after starting the thromboplastin infusion, intravenous LMWH treatment in different dosages started in groups 2 and 3 to achieve plasma levels between 0.27+/-0.01 and 0.36+/-0.02 anti-FXaUml(-1) or 0.62+/-0.08 and 0.90+/-0.07 antiFXaUml(-1) (mean+/-SD), respectively, during the time period of parallel administration of thromboplastin and LMWH (group 1=control; 4 dogs/group). In this time period, changes in factor V activity and fibrinogen concentration did not differ between group 2 and the control group. This was in contrast to group 3. The results of this study indicate that an efficacious interruption of the consumption reaction in cases of severe canine DIC requires high plasma heparin levels.