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1.
为研究日本医蛭(Hirudo nipponica)进食前后唾液腺的形态和超微结构特征,该文通过光学显微镜和电子显微镜对日本医蛭唾液腺进行观察。基于光学显微镜成像,观察到日本医蛭咽部具有三角形肌肉颚,唾液腺呈葡萄状依附在颚上,腺体呈乳白色且对称分布在颚周围。HE染色结果表明,唾液腺细胞是由卵球形的体细胞和细长的导管组成的,且细胞核位于细胞底部或边缘。未进食的日本医蛭唾液腺细胞染色浅,细胞质饱满;进食后的日本医蛭唾液腺细胞染色深,细胞质结构疏松。基于透射电子显微镜成像,观察到唾液腺细胞中存在球形分泌颗粒,且分泌颗粒内部存在高电子密度的致密成分。未进食的日本医蛭唾液腺细胞结构紧致,分泌颗粒相互挤压,且大量分泌颗粒内含有致密成分;进食后的日本医蛭唾液腺细胞结构疏松,分泌颗粒之间存在空隙,且分泌颗粒内致密成分消失。基于扫描电子显微镜成像,观察到唾液腺细胞呈葡萄状排列。未进食的日本医蛭唾液腺细胞表面光滑,细胞圆润;进食后的日本医蛭唾液腺细胞表面存在大量颗粒物质,细胞凹陷。以上结果表明,日本医蛭进食后,唾液腺细胞分泌出的多种分泌蛋白是分泌颗粒中的致密成分,而大部分分泌颗粒还存在于唾液腺细胞内。  相似文献   

2.
本文研究了新的层析介质(Cellufine)对原纯化工艺中SepharseCL-4B柱层析纯化后的乙肝表面抗原(HBsAg)组分及DNA组分的进一步纯化效果。结果表明:该层析介质可以提高HBsAg的纯度和收量,并对初步提纯DNA组分中的乙肝表面抗原有一定意义。并首次发现DNA组分中乙肝表面抗原的SDS-PAGB图谱较正常基因乙肝表面抗原的图谱缺少30KD的条带。  相似文献   

3.
本文采用回归分析法研究了超速离心纯化时,固定一次溴化钾密度梯度比例,选择不同的二次溴化钾梯度比例对下一步SepharoseCL-4B柱层析纯化收率的影响。结果表明:回归分析不仅能揭示纯化的最佳条件,即,二次溴化钾超速离心时溶液由240ml(1.04g/ml):800m1(1.28g/ml):600ml(1.32g/ml):50ml(1.34g/ml)构成时柱层析收率最高。而且还能解释层析纯化中出现的异常结果。  相似文献   

4.
结合薄层色谱、柱色谱、以及高效液相色谱对虾青素高产菌株-法夫酵母JMU-MVP14中的类胡萝卜素成分进行初步研究。研究结果表明,硅胶柱层析和氧化镁柱层析相结合的方法对法夫酵母JMU-MVP14菌体中的类胡萝卜素成分有很好的分离效果。经过柱层析分离纯化后,各组分中类胡萝卜素的种类单一,有利于进一步通过各种波谱技术对其进行定性。此方法弥补了单纯依靠高效液相色谱(ODS 柱)对法夫酵母 JMU-MVP14菌体中类胡萝卜素分离效果不佳,可供选择的商业化类胡萝卜素标准品少,液相保留时间漂移等因素给法夫酵母JMU-MVP14菌体中类胡萝卜素定性带来的不足。  相似文献   

5.
重组人亲环素A的表达、纯化及活性测定   总被引:1,自引:0,他引:1  
将RT-PCR扩增得到的亲环素A(CyPA)基因片段插入原核表达载体pET11c中,得到重组质粒pET11/CyPA,转入大肠杆菌获得高效表达。Spe-PAGE分析表明,重组CyPA表达量占菌体可溶性蛋白的40%以上。经50%硫酸铵沉淀和DEAESepharoseCL-6B柱层析可纯化重组CyPA。用糜蛋白酶偶联法测定显示重组CyPA具有肽基脯氨酸顺/反异构酶活性。  相似文献   

6.
正相和反相柱层析组合分离纯化紫杉醇   总被引:6,自引:0,他引:6  
采用正相氧化铝柱层析和反相C18柱层析从东北红豆杉培养细胞浸提物中分离纯化了紫杉醇。优化了氧化铝柱层析和反相柱层析的操作条件。实验发现,经过氧化铝柱层析后,测得的紫杉醇量大大增加。经两步层析,使紫杉醇的含量从小于1.0%提高到95%,样品中微量杂质继以重结晶步骤除去,即可获得纯度超过98%的紫杉醇晶体。采用13-CNMR对晶体分析,所得产物结构与文献上紫杉醇的结构一致。  相似文献   

7.
重组人亲环素A的表达,纯化及活性测定   总被引:9,自引:0,他引:9  
将RT-PCR扩增得到的亲环素A(CyPA)基因片段插入原核表达载体pET11c中,得到重组质粒pET11/CyPA,转入大肠杆菌获得高效表达。Spe-PAGE分析表明,重组CyPA表达量占菌体可溶性蛋白的40%以上。经50%硫酸铵沉淀和DEAESepharoseCL-6B柱层析可纯化重组CyPA。用糜蛋白酶偶联法测定显示重组CyPA具有肽基脯氨酸顺/反异构酶活性。  相似文献   

8.
潘太健  马瑞  曹春来  黄亮  赵腾  肖拥军 《生物磁学》2013,(24):4634-4637
摘要目的:建立一条新的毕赤酵母表达乙肝表面抗原(HepatitisBantigen,HBsAg)柱层析纯化方法,保持HBsAg结构完整性和提高免疫原性。方法:毕赤酵母发酵料液经过菌体破碎、聚乙二醇沉淀、疏水层析、超滤和凝胶分子筛精纯,收集HBsAg合格样品液适当稀释后加入铝佐荆吸附,制成乙肝疫苗半成品免疫BALB/c小鼠。结果:纯化产物经SDS-PAGE银染鉴定得单一条带,分子量在23kD左右,凝胶成像软件分析纯度超过95%;该纯化方法得到的HBsAg颗粒电镜观察得平均直径为22nm病毒样颗粒,结构较均一完整;自制疫苗免疫小鼠后,其血清抗体水平高于葛兰素史克生产的Engerix—B(安在时),存在显著性差异(P〈0.05)。结论:通过该方法纯化的HBsAg结构完整性良好,疫苗免疫效果优于酵母表达的Engerix—B,纯化路径简单高效,易于放大用于工业化生产。  相似文献   

9.
综述中国蛭类研究如下内容:(1)生态学。山蛭生态学,包括山蛭的生态分布,海南山蛭(Hhainana)的种群动态,对温度、土壤湿度和pH值的适应,以及对温、光、湿的综合反应和人类经济活动对其种群数量的影响;山蛭行为生态学,山蛭的运动包括慢缩短、快缩短、身体摆动和转动、洗刷运动、亲吻运动、觅食行为6程序,影响山蛭行为的一些因素以及对环境因素刺激的生态学意义;淡水水蜂生态学,包括浙江水田蛭类生活习性、广州水牛光润金线蛭种群数量动态与水体化学因子关系、广州水田吸血菲牛蛭生活水体化学环境;山蛭和水生吸血菲牛蛭的觅食、生长动态、生命周期和生殖生物学;(2)形态学、分类学和动物地理学。形态学包括山蛭机能组织学、山蛭器官系统解剖;分类学,中国蛭类动物有2亚纲(蛭蚓亚纲、真蛭亚纲)、3目(蛭蚓目、吻蛭目、无吻目)、9科、33属、111种,占世界蛭类物种数约1/6;动物地理学,包括世界山蛭科属动物地理,中国山蛭科动物地理、中国医蛭科动物地理。(3)蛭类的防治和驱避,淡水吸血蛭类防治所用农药种类,不同农药对海南山蛭的毒力(LD50、LD95)及使用,并比较了12种驱避剂对海南山蛭的驱避效果。(4)蛭类的医学利用,蛭素是蛭类唾液腺分泌的一种抗凝物质,蛭素有水蛭素(Hirudin)、山蛭素(Haemadin)和吻蛭素(Hementin)。记述了蛭素的分离、纯化和功能以及有关分子生物学内容。  相似文献   

10.
黄劭  孔天翰  祁俊华 《蛇志》2009,21(2):81-84
目的比较三种柱径的分子筛G-50凝胶层析柱分离东亚钳蝎蝎毒的柱效;并对分离所得组分作MTT(酶反应比色法)抗肿瘤活性作用研究,为从中研制和开发出高效、低毒的新型抗癌特效药筛选出目标组分。方法(1)采用三种规格的分子筛层析柱分离蝎毒;(2)HPLC色谱分析比较各组分的指纹图谱;(3)MTT法观察不同浓度(1、10、100mg/L)的蝎毒及其组分对四种肿瘤细胞(HL-60、A549、K562/ADR、K562/S等)的毒性作用。结果经过分子筛柱层析,可从蝎毒(Scorpion venom,SV)获取三个组分SVⅠ、SVⅡ、SVⅢ;经HPLC色谱分析,各组分明显含有四种以上单体成分;MTT法研究表明,SVⅡ对四种肿瘤细胞的细胞毒性较原毒强,剂量-效应关系较好,而SVⅠ、SVⅢ对四种肿瘤细胞抑制作用不明显。结论(1)利用大柱径的层析柱分离蝎毒的柱效较高;(2)组分SVⅡ是蝎毒抗癌的目标组分,且其对耐药细胞株(K562/ADR)的抑制作用比阳性对照组强,有待进一步的分离纯化,筛选出色谱纯的抗癌活性成分(多肽单体)。  相似文献   

11.
The tropical bont tick, Amblyomma variegatum can cause intense skin irritation and inflammation and bites that often develop into septic wounds or abscess in their host. Crude salivary gland extract (SGE) of partially engorged A. variegatum females as well as SGE protein fractions purified by three-step reverse phase HPLC procedure were tested for their anti-aggregatory effect on isolated human blood platelets stimulated with thrombin and compared with the effect of recombinant hirudin. At concentrations 10−3 and 5 × 10−3 μg protein/ml the following rank order of antiplatelet activity was detected: AV 16/3 (inhibitor purified from AV-III, third purification) > SGE > AV-II (fraction from first purification) > AV-III (fraction from first purification) > hirudin. The effect of all fractions tested was dose-dependent. For fraction AV 16/3, the inhibitory effect was 49 and 61% for 10−3 and 5 × 10−3 μg protein/ml, respectively. The results suggest that protein fractions from A. variegatum SGE possess an antithrombin effect on human blood platelets with hirudin-like activity. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

12.
The pharmacokinetics and the effects on the haemostatic system of hirudin were assessed in healthy volunteers after single doses of 1,000 AT-U/kg administered intravenously respectively subcutaneously. First clinical experiences on hirudin treatment in chronic DIC are reported.  相似文献   

13.
Dried saliva spot sampling is a minimally invasive technique for the spatial mapping of salivary protein distribution in the oral cavity. In conjunction with untargeted nano‐flow liquid chromatography tandem mass spectrometry (nanoLC–MS/MS) analysis, DSS is used to compare the proteomes secreted by unstimulated parotid and submandibular/sublingual salivary glands. Two hundred and twenty proteins show a statistically significant association with parotid gland secretion, while 30 proteins are at least tenfold more abundant in the submandibular/sublingual glands. Protein identifications and label‐free quantifications are highly reproducible across the paired glands on three consecutive days, enabling to establish the core proteome of glandular secretions categorized into eight salivary protein groups according to their biological functions. The data suggest that the relative contributions of the salivary glands fine‐tune the biological activity of human saliva via medium‐abundant proteins. A number of biomarker candidates for Sjögren's syndrome are observed among the gland‐specifically expressed proteins, which indicates that glandular origin is an important factor to consider in salivary biomarker discovery.  相似文献   

14.
Antistasin is a 15-kDa protein from the salivary glands of the Mexican leech, Haementeria officinalis, which manifests anticoagulant activity by inhibiting factor Xa. Previous work demonstrating the presence of this activity in salivary gland extracts and its partial purification has been reported (Tuszynski, G. P., Gasic, T. B, and Gasic, G.J. (1987) J. Biol. Chem. 262, 9718-9723). The present study includes further purification to homogeneity of antistasin and its subsequent fragmentation and complete amino acid sequence determination. The protein, which possesses 119 amino acid residues, is blocked at its amino terminus by the presence of a pyroglutamic acid residue and has an unusually high cysteine content, with 20 cysteine residues. The primary structure of antistasin shows no homology to hirudin, a 65-residue anticoagulant protein from the medicinal leech, Hirudo medicinalis. Of great interest is the finding of significant internal homology within antistasin where a 2-fold internal repeated structure is observed. At least four isoforms of antistasin have been identified in leech salivary gland extracts by high performance liquid chromatography analysis, and partial amino acid sequence analysis of these isoforms indicates they differ by 1 or 2 amino acid residues.  相似文献   

15.
Salivary gland secretions of three species of the medicinal leech differ in the level of their lysozyme, and peptidoglycan-lysing activity. Using a synthetic fluorogenic substrate, 4-methylumbelliferyltetra N-acetyl-β-chitotetraoxide, the glycosidase activity (as one of peptidoglycan-lysing activities) of salivary gland secretion of these species of the medicinal leech was quantitatively evaluated in comparison with egg lysozyme. It is suggested that lysozyme activity of the leech secretions is determined not only by 5 isoforms of destabilase-lysozyme, but by some other enzymes which can utilize these substrates including lysozymes other than i-type (invertebrate) lysozymes.  相似文献   

16.
Objective: Salivary gland secretions play an important role in promotion of wound healing. The healing of intra- or extra-oral wounds is delayed in desalivated rats. However, the specific role of each salivary gland in promoting wound healing is unknown. This study was aimed to investigate the effect of crude extracts of rat salivary glands on a simplified in vitro wound healing model. Design/methods: Cultured human keratinocytes (HaCat) and murine fibroblasts (3T3) were subjected to 48 h serum starvation, and were later activated by extracts of rat salivary glands, 1–10 μg protein/ml of each gland. The resultant cellular metabolic activity of the activated cells was determined 24 h later, measuring reduction of XTT by mitochondrial enzymes, and calculated relatively to positive controls [optimal supplementation of 10% fetal calf serum (FCS)], and negative controls (starved non-supplemented cells). Results: The relative stimulatory effect of parotid (P) extract on the cells was significantly lower than either submandibular (SM) or sublingual (SL) extracts. Under the assumption that physiologically, the cells are exposed to the combined effect of saliva secreted from all the glands, different combinations of the extracts were presented to the cells. The relative stimulation was maximal following treatment with the three glands extracts (P + SM + SL) and exceeded the effect of 10% FCS. Conclusion: The results suggest that each salivary gland has a specific effect on wound healing and the combination of the three extracts has an additive effect but no the sum of all individual glands. This model might be useful to study the wound healing effect of salivary glands. In partial fulfillment of the requirement for MD thesis, The Joyce and Irving Goldman School of Medicine, Faculty of Health Sciences, Ben Gurion University of the Negev, Beer Sheva, Israel.  相似文献   

17.
The effect of destabilase, a component of Hirudo medicinalis salivary gland secret, was investigated in organotypic tissue culture of dorsal root ganglia (DRG) of 10-11-day old chick embryos. Native destabilase in concentrations 0.01 and 0.05 ng/ml was active, inducing a more intensive neurite growth in DRG that in the control. The stabilizing activity of destabilase was lost following reverse-phase chromatography. Neurite-stimulating effects of the drug "pyjavit" is due presumably to neurite-stimulating activity of destabilase.  相似文献   

18.
本文报导了化学合成的水蛭素基因在酵母细胞中得到表达,井能分泌水蛭素到胞外。将该菌株培养物的上清液经硫酸铵沉淀和Sephadex G-50过滤后,用DEAE-SephadexA-25进行阴离子交换层析,进而用HPLC反相层析,得到表达产物重组水蛭素。经SDS-PAGE,氨基酸序列分析,抗凝血酶活力分析及血浆滴定实验等方法鉴定,证明该基因表达产物与天然水蛭素HV_2相同。  相似文献   

19.
Summary The prosomal glands of Tetranychus urticae (Acari, Tetranychidae) were examined light and electron microscopically. Five paired and one unpaired gland are found both in females and males. The silk spinning apparatus consists of paired silk glands which extend laterally on both sides of the esophagus into the pedipalps. There, they enter the terminal silk gland bag which opens into a silk bristle at the apex of the pedipalps. The salivary secretions are formed in three paired glands which have an interconnecting duct, the podocephalic canal. The dorsal podocephalic glands may produce a serous secretion, the anterior podocephalic glands a mucous secretion, and the coxal organ may add a liquid, ion-rich secretion. These secretions pass the podocephalic canal and reach the mouth at the apex of the gnathosome. The function of the paired tracheal organs and the unpaired tracheal gland is still unclear. The tracheal gland may produce a secretion which facilitates the movement of the fused chelicerae and the stylets.This study was financed by a grant from the Deutsche Forschungsgemeinschaft (DFG Se 162/12)  相似文献   

20.
Protein kinase C activity was partially purified from tick salivary glands by fast protein liquid chromatography anion-exchange chromatography. Enzyme activity was stimulated by Ca2+, phosphatidylserine, and diacylglycerol with the highest activity observed in the presence of all three modulators. Enzyme activity was inhibited by a synthetic pseudosubstrate peptide with an amino acid sequence resembling the protein kinase C substrate phosphorylation site. The protein kinase C activator, 1-oleoyl-2-acetyl-sn-glycerol (OAG), when added to whole in vitro salivary glands previously prelabeled with 32P, stimulated the phosphorylation of salivary gland proteins. Activators of protein kinase C (phorbol ester or OAG) did not stimulate fluid secretion by isolated tick salivary glands. OAG and phorbol ester had only minimal affects on the ability of dopamine to stimulate secretion by isolated salivary glands and dopamine's ability to increase salivary gland cyclic AMP.  相似文献   

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