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利用阴离子交换层析、凝胶过滤及阳离子交换层析三步方法, 从皖南尖吻蝮蛇毒中分离纯化到一个新的抗凝血因子ACFII(anticoagulation factorII) 。纯化的ACFII在PAGE、SDSPAGE和IEFPAGE图谱上均呈单一区带。ACFII由两条分子量为14.6 kD 的肽链通过二硫键连接在一起, 其等电点为7.0。ACFII具有显著的抗凝血活性, 在体外延长PPT 时间的最终浓度为0 .4 mg/L。ACFII不具有类凝血酶活性、磷脂酶A2 活性和纤溶活性,也没有出血活性和毒性, 是一种潜在的高效抗凝药物。 相似文献
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Anticoagulation factor II (ACF II), a coagulation factor X- binding protein from the venom of Agkistrodon acutus has both anticoagulant and hypotensive activities. Previous studies show that ACF II binds specifically with activated factor X (FXa) in a Ca(2+) -dependent manner and inhibits intrinsic coagulation pathway. In this study, the inhibition of extrinsic coagulation pathway by ACF II was measured in vivo by prothrombin time assay and the binding of ACF II to factor IX (FIX) was investigated by native polyacrylamide gel electrophoresis and surface plasmon resonance (SPR). The results indicate that ACF II also inhibits extrinsic coagulation pathway, but does not inhibit thrombin activity. ACF II also binds with FIX with high binding affinity in a Ca(2+) -dependent manner and their maximal binding occurs at about 0.1 mM Ca(2+) . ACF II has similar binding affinity to FIX and FX as determined by SPR. Ca(2+) has a slight effect on the secondary structure of FIX as determined by circular dichroism spectroscopy. Ca(2+) ions are required to maintain in vivo function of FIX Gla domain for its recognition of ACF II. However, Ca(2+) at high concentrations (>0.1 mM) inhibits the binding of ACF II to FIX. Ca(2+) functions as a switch for the binding between ACF II and FIX. ACF II extends activated partial thromboplastin time more strongly than prothrombin time, suggesting that the binding of ACF II with FIX may play a dominant role in the anticoagulation of ACF II in vivo. 相似文献
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蕲蛇酶对大白鼠和家兔实验性脑血栓的溶栓作用 总被引:2,自引:1,他引:2
采用血小板聚集诱导剂二磷酸腺苷(ADP)加肾上腺素(Ad)从家兔颈内动脉或大白鼠颈总动脉注入,以形成脑血栓,2h后各组动物分别从静脉给予不同剂量蕲蛇酶(150、300和600mg/kg),阳性对照药潘生丁(10mg/kg)及空白对照生理盐水(1ml/kg)。以脑组织对伊文思蓝通透性改变及脑组织切片计算血栓数目为指标,判断蕲蛇酶对血栓的影响。结果不同剂量蕲蛇酶组对大鼠或家兔的实验性脑血栓均比生理盐水组血栓消褪加快,形成的血栓数目减少,脑组织伊文思蓝含量亦明显减少;潘生丁组亦显示促血栓消褪的效果 相似文献
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Acutolysin D isolated from the venom of Agkistrodon acutus is a protein of 44 kDa with marked hemorrhagic and proteolytic activities. The metal-ion- and pH-induced conformational changes of acutolysin D have been studied by following fluorescence and activity measurements. Here we provide evidence for the fact that native holo-acutolysin D adopts two different conformations, native state a, stable in the weak acidic pH range from 5.5 to 7.0 with low activity, and native state b, stable in the weak alkaline pH range from 8.0 to 9.0 with high activity. Holo-acutolysin D has an optimum pH of 9.0 for caseinolytic activity and a maximum fluorescence at pH 9.0. The protein adopts the most stable conformation at pH 9.0. The addition of 1 mM Zn(2+) shifts both the alkali-induced unfolding transition curve and the alkali-induced inactivation curve toward higher pH value but has little effect on the acid-induced unfolding transition curve. No obvious effects on the pH-induced unfolding transition curve and the pH-dependent activity curve have been observed after the addition of 1 mM Ca(2+) to holo-acutolysin D. The results indicate that Zn(2+) is essential for its CA, while Ca(2+) is not essential for its CA. Removal of Ca(2+) and Zn(2+) from the protein enhances its sensitivity to pH and significantly reduces its overall stability during acid-induced denaturation. The kinetic results of the demetalization of holo-acutolysin D show that the demetalization rate constant K(1) for a slower reaction linearly decreases with the pH increase from 5.0 to 9.0, while K(2) for the faster reaction linearly increases with the pH change from 5.0 to 7.0. It is also evident from the present work that the free Zn(2+)-induced inactivation in the pH range from 8.0 to 9.0 should be attributed to the effect of Zn(OH)(2) precipitation on the protein. 相似文献
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蕲蛇酶对80例高粘血症的纤维蛋白原浓度作用的研究 总被引:2,自引:0,他引:2
目的 通过蕲蛇酶对 80例高粘血症患者的治疗 ,研究其对纤维蛋白原的影响 ,试图寻找防栓抗栓的理想药物。方法 采用蕲蛇酶注射液 0 .75 u静脉滴注 ,每天 1次 ,连用 1 4天 ,观察治疗前后临床症状、甲襞微循环 ( NFM)、血液流变学及脂代谢的变化。结果 该药除具有缓解临床症状 ,改善 NFM,降低血粘度、红细胞压积、血小板吸附率及改变脂代谢紊乱等作用外 ,还能有效地降低血浆纤维蛋白原含量。结论 蕲蛇酶注射液对防治血栓形成具有重要意义。 相似文献
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目的 研究在自然环境条件下人工孵化尖吻蝮蛇卵的孵化成活率。 方法 试验于 2 0 0 1年 6~9月在湖南永州之野异蛇实业有限公司试验蛇场内进行。试验基地室内外结合室内面积为 4 m× 3 m,建成多层立体式蛇窝。室外面积为 1 5 m× 1 0 m,灌木和杂草覆盖度 90 %以上 ,有 1个 3 m× 2 m的饮水池 ,供蛇饮水。种蛇 1 5条。孵化湿度 75 %~ 85 % ,温度比场外自然环境温度略低 2~ 3℃。 结果 尖吻蝮蛇平均产卵数为 1 4 .3枚 ;平均孵化天数为 2 2 .5天 ,孵化率为 95 %以上。 结论 在自然环境条件下可以人工孵化尖吻蝮蛇卵 ,而且受精良好的雌尖吻蝮蛇卵出壳率高 相似文献
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本文对尖吻蝮蛇伤患者的甲皱微循环和凝血象同时进行了动态观察。结果显示尖吻蝮蛇伤患者中毒程度不同,甲皱微循环也发生不同程度的改变,另中毒程度越严重,凝血象变化也越显著.甲皱微循环和凝血象的变化与临床病情变化是一致的,对病情的转归及预后估计均有一定的指导意义。 相似文献
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目的:对人工饲养蕲蛇与野生蕲蛇中重金属元素及氨基酸含量进行测定和比较分析研究。方法:采用原子吸收法对蕲蛇中Cu、Hg、Cd、Pb、As含量进行测定;全自动氨基酸分析仪测定蕲蛇中氨基酸含量并进行相关性分析。结果:人工饲养蕲蛇与野生蕲蛇中重金属元素含量为均低于《中国药典》2010版限定值。人工饲养蕲蛇与野生蕲蛇中的氨基酸含量丰富,种类构成完整,均含有17种人体所需要的氨基酸,两者氨基酸含量的相关系数r=0.9991。结论:人工饲养蕲蛇与野生蕲蛇氨基酸含量和组成相似,两者存在线性正相关关系,且蕲蛇中重金属含量符合《中国药典》2010版标准,人工饲养蕲蛇可以作为野生蕲蛇的优良替代品。 相似文献
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Li‐Yun Zhang Xiao‐Long Xu Zhao‐Feng Luo Hao Wu Deng‐Ke Shen Li‐Li Peng Yang‐Zhong Liu 《Biopolymers》2010,93(2):141-149
AA‐NADase from Agkistrodon acutus venom is a unique multicatalytic enzyme with both NADase and AT(D)Pase activities. Among all identified NADases, only AA‐NADase contains Cu(II) and has disulfide‐bond linkages between two peptide chains. The effects of the reduction of the disulfide‐bonds and Cu(II) in AA‐NADase by small‐molecule reductants on its NADase and ADPase activities have been investigated by polyacrylamide gel electrophoresis, high performance liquid chromatography, electron paramagnetic resonance spectroscopy and isothermal titration calorimetry. The results show that AA‐NADase has six disulfide‐bonds and fifteen free cysteine residues. L‐ascorbate inhibits AA‐NADase on both NADase and ADPase activities through the reduction of Cu(II) in AA‐NADase to Cu(I), while other reductants, dithiothreitol, glutathione and tris(2‐carboxyethyl)phosphine inhibit both NADase and ADPase activities through the reduction of Cu(II) to Cu(I) and the cleavage of disulfide‐bonds in AA‐NADase. Apo‐AA‐NADase can recover its NADase and ADPase activities in the presence of 1 mM Zn(II). However, apo‐AA‐NADase does not recover any NADase or ADPase activity in the presence of 1 mM Zn(II) and 2 mM TCEP. The multicatalytic activity relies on both disulfide‐bonds and Cu(II), while Cu(I) can not activate the enzyme activities. AA‐NADase is probably only active as a dimer. The inhibition curves for both ADPase and NADase activities by each reductant share a similar trend, suggesting both ADPase and NADase activities probably occur at the same site. In addition, we also find that glutathione and L‐ascorbate are endogenous inhibitors to the multicatalytic activity of AA‐NADase. © 2009 Wiley Periodicals, Inc. Biopolymers 93: 141–149, 2010. This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com 相似文献
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五步蛇蛇毒金属蛋白酶cDNA的克隆和序列分析 总被引:3,自引:0,他引:3
抽提五步蛇毒腺总RNA,通过反转录PCR(RT-PCR)扩增出五步蛇毒腺中一种低分子量金属蛋白酶(aculysinl)的cDNA,克隆到pGMT-vector并测定了全序列.推导其编码的蛋白质序列,发现aculysinl是以酶原形式合成的分泌蛋白,酶原包括信号肽、前肽、金属蛋白酶成熟肽和间隔肽4个部分.金属蛋白酶成熟肽与其它蛇毒金属蛋白酶相比,蛋白质一级结构具有一定的同源性,有一个保守的Zn2+结合位点:HEXXHXXGXXH.Aculysinl含有6个半胱氨酸,推测形成3对链内二硫键.五步蛇低分子量金属蛋白酶cDNA的克隆,为研究蛇毒金属蛋白酶结构与功能的关系,以及开发治疗血栓药物打下了良好的基础 相似文献
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目的探讨重症五步蛇伤患者行深筋膜室网状切开的早期应用。方法选择2007年4月~2011年12月我院收治被五步蛇咬伤后3h内就诊,且患肢组织压在25mmHg以上的患者44例,其中行深筋膜室网状切开13例作为研究组(A组),使用传统保守非手术治疗31例作为对照组(B组),观察两组患者72h内组织压的变化、肿胀程度的改变、创口出血及坏死情况,并进行比较。结果两组比较,A组24h后组织压基本降至正常,肿胀程度比B组轻;A组患者伤口有明显出血渗血,早期B组优于A组,但3h后两组的出血情况对比无明显差异。A组2例患者伤处有片状坏死;B组绝大部分患者72h后经切除坏死组织后肿胀明显消退,1例患者因骨筋膜室综合征导致截肢,两组对比有显著统计学差异。结论在重症五步蛇伤中,审慎深筋膜室网状切开患肢,可避免组织坏死、骨筋膜室综合征形成及大出血的发生。 相似文献
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Two series of indolyldiketopiperazines were synthesized starting from methyl 1‐substituted‐1,2,3,4‐tetrahydro‐β‐carboline‐3‐carboxylate hydrochlorides via N‐bromo‐succinimide (NBS) as an important reagent. All eight compounds were characterized by nuclear magnetic resonance (NMR) and elemental analysis. Furthermore, the mechanisms of NBS‐reacted rearrangements are also discussed. Chirality 26:790–792, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
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从皖南尖吻蝮蛇(Agkistrodonacutus)毒液中经DEAE-Sepharose和SephacrylS-200两步凝胶柱层析首次纯化出一种中分子量出血毒素(简称AaHⅣ).经SDS-PAGE和等电聚焦凝胶电泳测定其分子量为44kD,等电点为pH5.0.从500mg粗毒中可获得20mgAaHⅣ纯品.AaHⅣ有较强的出血活性,最小出血剂量(MHD)为0.4μg. 相似文献
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本文首次报道了五步蛇身体主要部位的数量性状与其排毒量的关系。其中我们发现与排毒量有关的部位是头积、体粗、体重、佛指长。 相似文献
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目的为了探索乙醇对五步蛇毒毒性的影响。方法将五步蛇毒不同浓度致死量经不同浓度乙醇体外处理后,选择小白鼠分别给予皮下注射、口服,并将致死量蛇毒于小白鼠皮下注射后立即于局部注射乙醇,观察蛇毒毒性情况。结果使用乙醇体外处理后的五步蛇毒毒性明显下降,小白鼠经皮下注射致死量五步蛇毒后立即在局部注射50%异蛇米酒或75%乙醇0.1~0.2ml有一定的保护作用,口服20倍致死量五步蛇毒未发现有毒性表现。结论五步蛇毒体外经过乙醇处理后毒性明显下降。口服五步蛇毒是安全的。蛇毒进入皮下后立即用乙醇处理有一定的治疗效果。 相似文献
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