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1.
为深入探讨嗜水气单胞菌(Aeromonas hydrophila,Ah)主要粘附素在菌体侵入宿主和介导宿主产生免疫过程可能扮演的角色,对Ah菌ZN1株主要粘附素重组基因的表达产物的部分生物学功能进行分析。通过酶联免疫吸附试验、细胞与Ah菌的粘附试验及粘附抑制和阻断试验,研究分析克隆表达的Mah-TrxA(硫氧还蛋白与主要粘附素形成的融合蛋白)生物学功能。结果显示:克隆表达的Mah-TrxA融合蛋白具有良好的抗原性和免疫原性,对不同Ah菌株有交叉粘附抑制的作用,抗原竞争性抑制试验和抗体阻断试验均能显著减少不同Ah菌株对EPC的粘附作用。因此,克隆表达的Mah-TrxA确为ZN1菌株的主要粘附素;基因工程技术以融合蛋白形式表达的Mah-TrxA与野生菌株ZN1表达的主要粘附素具有类似的生物学活性。  相似文献   

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3.
The cellular cues that guide neuronal growth cones toward their targets are highly conserved in such diverse organisms as insects and vertebrates. Evidence presented here suggests that the molecular mechanisms underlying these events may be equally conserved. This article describes the structure and function of fasciclin II, a glycoprotein expressed on a subset of fasciculating axons in the grasshopper embryo. Antibody perturbation experiments suggest that fasciclin II functions in mediating one form of neuronal recognition: selective fasciculation. Fasciclin II is a member of the immunoglobulin gene superfamily and is homologous in structure and function to the neural cell adhesion molecule N-CAM and to several other vertebrate cell adhesion molecules.  相似文献   

4.
目的 研究颈动脉粥样硬化患者不同中医证型的血脂水平及血清脂蛋白残粒(RLP-C)、细胞间黏附分子1(sICAM-1)和血管细胞黏附分子1(sVCAM-1)含量差异。方法 筛选2015年1月至2015年12月就诊于航天中心医院的颈动脉粥样硬化的患者90例设为中医组,同时筛选健康体检者90例设为正常组,取患者晨起空腹静脉血进行检测。观察颈动脉粥样硬化患者痰浊阻遏证、脾肾阳虚证、肝肾阴虚证、阴虚阳亢证以及气滞血瘀证情况,比较不同中医证候类型患者与正常组的血脂水平及其血清RLP-C、sICAM-1及sVCAM-1含量。结果 90例颈动脉粥样硬化患者中,54例为痰浊阻遏证,占总患病人数的60.00%,显著高于脾肾阳虚证、肝肾阴虚证、阴虚阳亢证以及气滞血瘀证患者,差异具有统计学意义(P<0.05);不同中医证候类型患者的血清TG、TC和LDL-C水平要高于正常组,而HDL-C含量要低于正常组,差异均具有统计学意义(P<0.05);此外,痰浊阻遏证患者的TG、TC、LDL-C含量高于其他中医证候型患者,而HDL-C含量低于其他中医证候型患者,差异均具有统计学意义(P<0.05);不同中医证候类型患者的血清RLP-C、sICAM-1及sVCAM-1水平要高于正常组,且痰浊阻遏证患者血清RLP-C、sICAM-1及sVCAM-1水平要高于其他中医证候型患者,差异均具有统计学意义(P<0.05)。结论 颈动脉粥样硬化患者主要为痰浊阻遏证候,且颈动脉粥样硬化患者与健康体检者的RLP-C及其相关指标差异显著,其中痰浊阻遏证患者最为明显。  相似文献   

5.
Within the bilaterally symmetric vertebrate body plan, many organs develop asymmetrically. Here, it is demonstrated that a cell adhesion molecule, N-cadherin, is one of the earliest proteins to be asymmetrically expressed in the chicken embryo and that its activity is required during gastrulation for proper establishment of the left-right axis. Blocking N-cadherin function randomizes heart looping and alters the expression of Snail and Pitx2, later components of the molecular cascade that regulate left-right asymmetry. However, the expression of other components of this cascade (Nodal and Lefty) was unchanged after blocking N-cadherin function, suggesting the existence of parallel pathways in the establishment of left-right morphogenesis. Here, the results suggest that N-cadherin-mediated cell adhesion events are required for establishment of left-right asymmetry.  相似文献   

6.
The neural cell adhesion molecule (NCAM) can influence a number of diverse intercellular events, including junctional communication, the association of axons with pathways and targets, and signals that alter levels of neurotransmitter enzymes. These pleiotropic effects appear to reflect the ability of NCAM to regulate membrane-membrane contact required to initiate specific interactions between other molecules. Such regulation can occur through changes in either NCAM expression or the molecule's content of polysialic acid (PSA). When NCAM with a low PSA content is expressed, adhesion is increased and contact-dependent events are triggered. In contrast, the large excluded volume of NCAM PSA can inhibit cell-cell interactions through hindrance of overall membrane apposition.  相似文献   

7.
监测了实验感染兔瘟病兔15例的血清溶菌酶水平的动态变化,结果表明,潜伏期血清溶菌酶含量明显高于接种病毒前检测出的正常值,以后略有下降,但在濒死期升至最高值,在发病的不同时期,体温交化与血清溶菌酶含量的变化不呈平行关系,体温变化迅速,而血清溶菌酶含量在病早期快速升高到高峰值之后相当稳定。结论是,兔瘟病毒感染兔体能导致单核巨噬细胞系统功能的迅速增强。  相似文献   

8.
JAM-C is an adhesion molecule that is expressed on cells within the vascular compartment and epithelial cells and, to date, has been largely studied in the context of inflammatory events. Using immunolabeling procedures in conjunction with confocal and electron microscopy, we show here that JAM-C is also expressed in peripheral nerves and that this expression is localized to Schwann cells at junctions between adjoining myelin end loops. Sciatic nerves from JAM-C-deficient [having the JAM-C gene knocked out (KO)] mice exhibited loss of integrity of the myelin sheath and defective nerve conduction as indicated by morphological and electrophysiological studies, respectively. In addition, behavioral tests showed motor abnormalities in the KO animals. JAM-C was also expressed in human sural nerves with an expression profile similar to that seen in mice. These results demonstrate that JAM-C is a component of the autotypic junctional attachments of Schwann cells and plays an important role in maintaining the integrity and function of myelinated peripheral nerves.  相似文献   

9.
进展性缺血性脑卒中危险因素分析   总被引:1,自引:0,他引:1  
目的探讨与进展性缺血性脑卒中相关的危险因素.方法查阅近10余年来国内外关于进展性缺血性脑卒中的相关文献,分析与进展性缺血性脑卒中相关因素,为临床防治进展性缺血性脑卒中提供理论依据.结果研究表明:缺血区的脑血流量下降、血压变化、高血糖、发热与感染、脂蛋白与含铁蛋白含量、颈动脉粥样硬化及斑块形成、血浆总同型半胱氨酸水平、血清可溶性细胞间黏附分子1、白细胞流变特性及分子流变特性、血浆内皮素和一氧化氮含量的变化及谷氨酸(Glu)浓度等均与进展性缺血性脑卒中有关.结论与脑卒中进展相关的诸因素可增加致残率,预后差,治疗困难,对这些因素的关注有助于防治进展性缺血性脑卒中.  相似文献   

10.
A cell-free protein-synthesizing system made from rabbit reticulocytes was used to incorporate (14)C-amino acids into hemoglobin. Electrophoretic analyses of the soluble products of this cell-free system revealed a fraction containing rabbit (14)C-alpha chains in addition to the rabbit (14)C-hemoglobin. The addition of isolated human hemoglobin beta chains to this system during active synthesis inhibited the release of newly synthesized rabbit (14)C-beta chains into solution from the ribosome fraction. This inhibition was possibly a result of hybrid hemoglobin formation between rabbit alpha and human beta chains. A model of hemoglobin construction in which soluble alpha chains are intermediates is suggested. These alpha chains may aid in the release of beta chains from the polyribosomes during the completion of the hemoglobin molecule.  相似文献   

11.
以猪型布鲁氏菌的BLS分子作为研究对象,通过重组蛋白质的纯化以及多克隆抗体的制备,研究了重组rBLS分子的免疫原性。结果表明:布鲁氏菌BLS分子具有较好的抗原性质,可以刺激家兔产生相应的抗体。  相似文献   

12.
GOODMAN JW 《Science (New York, N.Y.)》1963,139(3561):1292-1293
Peptic digestion of fraction III from papain-digested rabbit serum gamma-globulin produces a variety of smaller fragments. Some are too large to pass through a dialysis bag, and these retain the capacity to precipitate with antiserum to rabbit gamma-globulin. Others pass through the bag and fail to precipitate with antibody, but they can inhibit the precipitation of antibody with fraction III. This indicates that antigenic determinants of the gamma-globulin molecule are carried in these fragments.  相似文献   

13.
Familial hyperlipemia is an inherited disease associated with early onset of coronary atherosclerosis. In a survey of a student population in Sweden, an estimated case incidence of 2 to 3 percent was discovered. This study also demonstrates that there is probably a heterogeneity of causes for the primary elevation of blood triglycerides in man.  相似文献   

14.
Localization of PDGF-B protein in macrophages in all phases of atherogenesis   总被引:74,自引:0,他引:74  
Lesions of atherosclerosis occur in the innermost layer of the artery wall and consist primarily of proliferated smooth muscle cells surrounded by large amounts of connective tissue, numerous lipid-laden macrophages, and varying numbers of lymphocytes. Growth-regulatory molecules may be involved in intimal accumulation and proliferation of smooth muscle cells responsible for the occlusive lesions of atherosclerosis. Platelet-derived growth factor (PDGF) B-chain protein was found within macrophages in all stages of lesion development in both human and nonhuman primate atherosclerosis. Thus macrophages may play a critical role in the disease by providing PDGF, a potent chemotactic and growth-stimulatory molecule, to the intimal smooth muscle cells.  相似文献   

15.
SynCAM,a synaptic adhesion molecule that drives synapse assembly   总被引:1,自引:0,他引:1  
Synapses, the junctions between nerve cells through which they communicate, are formed by the coordinated assembly and tight attachment of pre- and postsynaptic specializations. We now show that SynCAM is a brain-specific, immunoglobulin domain-containing protein that binds to intracellular PDZ-domain proteins and functions as a homophilic cell adhesion molecule at the synapse. Expression of the isolated cytoplasmic tail of SynCAM in neurons inhibited synapse assembly. Conversely, expression of full-length SynCAM in nonneuronal cells induced synapse formation by cocultured hippocampal neurons with normal release properties. Glutamatergic synaptic transmission was reconstituted in these nonneuronal cells by coexpressing glutamate receptors with SynCAM, which suggests that a single type of adhesion molecule and glutamate receptor are sufficient for a functional postsynaptic response.  相似文献   

16.
为了探讨miR-202在鱼类胚胎发育中的功能,采用实时定量反转录PCR技术和整体原位杂交技术检测了miR-202在斑马鱼胚胎发育阶段的表达。结果发现miR-202是母源性分子并在斑马鱼胚胎发育过程中持续表达,尤其在早期胚胎发育阶段表达水平较高。在此基础上,采用基因沉默技术在斑马鱼受精卵中显微注射miR-202的反义锁核苷酸,实时荧光定量反转录PCR技术和整体原位杂交技术结果显示miR-202反义锁核苷酸可以显著下调斑马鱼胚胎中miR-202表达水平,同时发现反义抑制miR-202后胚胎发育停滞在4 hpf时左右。共同注射miR-202前体可以部分挽救反义抑制miR-202后导致的胚胎发育停滞。本研究证明miR-202在斑马鱼胚胎发育过程中起着重要的调控作用,其功能是斑马鱼胚胎早期发育所必需的。为进一步探索miR-202在鱼类胚胎发育过程的功能奠定了基础。  相似文献   

17.
从烟草花叶病毒(Tobacco mosaic virus,TMV)感染的发病烟草叶片中提取总RNA,通过RT-PCR扩增得到其运动蛋白基因,将扩增产物克隆到pMD18-T载体上.DNA序列分析表明,所得运动蛋白基因全长为807 bp,与已报道的TMV-U1株系核苷酸和氨基酸同源性均为100%.将目的基因亚克隆到原核表达载体pET-29a上,并转化大肠杆菌BL21(DE3),IPTG诱导4 h后蛋白表达量达到最大,超声波显示所得融合蛋白以不可溶形式存在.SDS-PAGA检测蛋白表达情况,表达产物与目的蛋白大小一致,割胶免疫注射家兔得到抗体,ELISA测定效价为25600,Western-blot检测证明在烟草叶片被侵染早期MP得到表达,且抗体特异性良好.  相似文献   

18.
对凡纳滨对虾进行血窦注射微囊藻毒素MC-LR染毒,取染毒前后肝胰腺及血细胞,采用Illumina Hiseq 2500测序平台进行基因表达谱分析,并对差异基因的基因本体(gene ontology,GO)注释和京都基因与基因组百科全书(kyoto encyclopedia of genes and genomes,KEGG)通路进行显著性富集分析。结果发现,酚氧化酶原、胰蛋白酶及C型凝集素等基因有显著的差异性表达。在GO富集性分析中发现细胞粘附显著性差异表达,细胞杀伤及细胞粘附分子结合物差异表达。KEGG富集性分析发现血细胞中吞噬体显著性差异表达,细胞凋亡、内吞作用和细胞粘附分子等通路呈表达差异。结果表明,凡纳滨对虾在被MC-LR染毒后,细胞免疫是抵御毒素的重要部分,其中细胞粘附和吞噬作用在抵御MC-LR对虾体的毒害过程中发挥了重要作用。  相似文献   

19.
The aim of this study is to reveal the regulation mechanism of the effect of Semen vaccariae and Taraxacu mogono on the cell-cell adhersion molecule, E-cadherin and b-catenin on the proliferation role and secretion function of bovine mammary epithelial cells cultured in vitro. Firstly, the epithelial character of bovine mammary epithelial cells was authenticated using immunofluorescence, then the cell grow curve was observed and investigated after S. vaccariae and T. mogono treatment. On the effect of S. vaccariae and T. mogono, cell adhesion molecules E-cadherin, b-catenin and CycinD1 mRNA and protein were detected by qRT-PCR and Western blotting, respectively. The results showed that the cellular keratin 18 expressed positively and proliferated vigorously after S. vaccariae and T. mogono treament. The mRNA and protein levels of E-cadherin and CycinD1 were remarkably higher (P<0.05) in 36 h after S. vaccariae and T. mogono treatment. The cell proliferation at 36 h was increased significantly (P<0.05). In conclusion, S. vaccariae and T. mogono have a positive impact on the cell proliferation and an effect on the adhesion molecules E-cadherin, b-catenin and CycinD1 in the Wnt signaling pathway.  相似文献   

20.
Cadherins are transmembrane proteins that mediate adhesion between cells in the solid tissues of animals. Here we present the 3.1 angstrom resolution crystal structure of the whole, functional extracellular domain from C-cadherin, a representative "classical" cadherin. The structure suggests a molecular mechanism for adhesion between cells by classical cadherins, and it provides a new framework for understanding both cis (same cell) and trans (juxtaposed cell) cadherin interactions. The trans adhesive interface is a twofold symmetric interaction defined by a conserved tryptophan side chain at the membrane-distal end of a cadherin molecule from one cell, which inserts into a hydrophobic pocket at the membrane-distal end of a cadherin molecule from the opposing cell.  相似文献   

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