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1.
纤溶酶原激活剂抑制物2型(PAI-2)是一种多功能蛋白质,除了能有效抑制尿激酶(uPA)和双链组织型纤溶酶原激活物(tPA)而调节纤溶活性外,还参与了很多其它的生理病理过程,例如组织重建、胚胎发育、感染、免疫系统发育、肿瘤浸润和迁移等。更有研究表明胞内型PAI-2在抑制细胞凋亡方面也发挥着重要作用。本文就近年来PAI-2抑制细胞凋亡的研究进展作一综述。  相似文献   

2.
登革2型病毒调控血管内皮细胞纤溶系统相关蛋白的表达   总被引:3,自引:0,他引:3  
目的观察登革2型病毒(DV2)对人脐静脉血管内皮细胞(HUVEC)表达组织纤溶酶原激活物(tPA)和纤溶酶原激活物抑制物1(PAI-1)的影响。方法应用胰酶消化分离HUVEC并进行传代培养,用生长良好的第2.3代细胞进行试验。用cell counting kit-8(CCK-8)测定DV2感染后细胞活性变化;发色底物法测定感染DV2组和对照组培养液中tPA、PAI-1活性;RT-PCR检测细胞内tPA和PAI-1 mRNA水平。结果DV2感染对细胞活力的影响与对照组相比差异无统计学意义。感染DV2组培养液中tPA活性在12~72h显著升高(P〈0.05);DV2诱导HUVEC表达tPA mRNA的水平显著上调,12h达到峰值,以后渐降,72h mRNA表达水平仍高于对照组(P〈0.01)。而DV2感染组培养液中PAI-1活性和PAI-1 mRNA的表达与对照组比较差异无统计学意义(P〉0.05)。结论DV2感染可显著上调HUVEC的tPA mRNA转录,增强内皮细胞tPA蛋白的分泌,而不影响PAI-1 mRNA的转录或改变内皮细胞PAI-1的分泌。结果提示DV2可活化但并不损伤内皮细胞,诱发内皮细胞增强表达纤溶酶原激活物而致使纤溶系统失衡,引起纤溶亢进,这可能是诱发DHF/DSS患者急性期出血、低血容量性休克等体征的主要因素之一。  相似文献   

3.
目的:观察体外培养的血管内皮细胞低氧低糖损伤后组织型纤溶酶原激活剂(tPA)、Ⅰ型纤溶酶原激活物抑制因子(PAI-1)表达变化,探讨脑缺血后纤溶系统的变化及机制。材料和方法:制备体外内皮细胞低氧低糖损伤模型,利用HE染色、免疫细胞化学染色观察tPA、PAI-1表达变化。结果:低氧低糖损伤后,tPA、PAI-1表达均明显增强。结论:成功制备体外内皮细胞低氧低糖损伤模型。内皮细胞低氧低糖损伤可以诱导tPA、PAI-1表达增多,进一步说明脑缺血损伤后tPA、PAI-1表达增加并参与损伤过程。  相似文献   

4.
目的:观察LPS对脐静脉血管内皮细胞(HUVECs)表达组织纤溶酶原激活物(tPA)和纤溶酶原激活物抑制物1(PAI-1)的影响。 方法: 用生长良好的第2、3代HUVECs进行试验。用cell counting kit-8(CCK-8)测定LPS刺激后细胞活性变化;发色底物法测定LPS组和对照组培养液中tPA, PAI-1活性;RT-PCR检测细胞内tPA和PAI-1 mRNA水平。 结果: 与对照组相比,LPS(10 mg/L)对细胞活性没有明显差异。LPS诱导PAI-1活性在24-72 h显著升高(P<0.05),且显著上调PAI-1 mRNA,24 h达到峰值,以后渐降,72 h达到正常水平。而LPS组与对照组tPA活性与tPA mRNA无明显差异(P>0.05)。 结论: LPS(10 mg/L)可显著上调PAI-1 mRNA转录和分泌而不影响tPA mRNA,结果提示LPS可活化内皮细胞,诱发PAI-1 mRNA表达和蛋白分泌而抑制纤溶系统,这有利于微血栓的形成、血栓稳定,血液凝固和DIC发生。  相似文献   

5.
背景:前期研究发现醒脑静能有效抑制兔心肌缺血再灌注模型的炎症递质及促纤溶作用,但是影响纤溶系统活性的作用机制未完全明确。目的:观察醒脑静对重组人肿瘤坏死因子α介导人脐静脉内皮细胞分泌组织型纤溶酶原激活物和纤溶酶原激活物抑制剂1及其基因表达的影响。方法:取3-5 代人脐静脉内皮细胞,在培养基中添加10 μg/L 重组人肿瘤坏死因子α介导人脐静脉内皮细胞分泌组织型纤溶酶原激活物和纤溶酶原激活物抑制剂1及其基因表达,醒脑静组加入不同浓度(5,10,20 mL/L)的醒脑静干预,阳性对照组添加氟伐他汀(1 μmol/L),并设立单纯人脐静脉内皮细胞培养的空白对照组。培育24 h后采用酶联免疫吸附双抗体夹心法(ELISA)检测细胞上清液组织型纤溶酶原激活物和纤溶酶原激活物抑制剂1水平;采用反转录聚合酶链反应检测人脐静脉内皮细胞的组织型纤溶酶原激活物和纤溶酶原激活物抑制剂1的mRNA表达。结果与结论:重组人肿瘤坏死因子α组纤溶酶原激活物抑制剂1分泌和mRNA表达较空白对照组显著升高 (P < 0.05),组织型纤溶酶原激活物分泌和mRNA表达较空白对照组显著降低(P < 0.05)。不同浓度醒脑静组纤溶酶原激活物抑制剂1分泌和mRNA表达均较重组人肿瘤坏死因子α组显著降低(P < 0.05),而组织型纤溶酶原激活物分泌和mRNA表达均较重组人肿瘤坏死因子α组显著升高(P < 0.05),且呈剂量依赖关系。结果证实,醒脑静作用可逆转重组人肿瘤坏死因子α所致的人脐静脉内皮细胞的纤溶活性。 中国组织工程研究杂志出版内容重点:组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程全文链接:  相似文献   

6.
内皮素(Endothelin-1,ET-1)为体内最强的缩血管多肽。纤溶系统在急性脑梗死(ACI)的发生发展中起着十分重要的作用,组织型纤溶酶原激活物(t-PA)和纤溶酶原激活物抑制物-1(PAI-1)的水平是纤溶活性的重要检测指标,  相似文献   

7.
目的: 观察胰岛素和葡萄糖对缺氧血管内皮细胞分泌组织型纤溶酶原激活物(tPA)及其抑制物-1(PAI-1)的影响。 方法:培养人脐静脉内皮细胞株ECV-304。分组实验:(1)常氧组;(2)在缺氧条件下又分为Ⅰ:缺氧对照组;Ⅱ:低浓度组:胰岛素150 mU/L、葡萄糖5.5 mmol/L;Ⅲ:中浓度组:胰岛素450 mU/L、葡萄糖15 mmol/L;Ⅳ:高浓度组:胰岛素900 mU/L、葡萄糖30 mmol/L;Ⅴ:渗透压对照组:甘露醇24.5 mmol/L。取培养4、8、12 h 3个时点,用ELISA法测定细胞培养上清液tPA、PAI-1抗原。结果:缺氧明显增加tPA和PAI-1抗原分泌,tPA/PAI-1值明显增加(P<0.01)。胰岛素和葡萄糖能够刺激缺氧内皮细胞分泌tPA和PAI-1抗原,在缺氧8 h以内,tPA/PAI-1比值明显增加(P<0.05)。随缺氧时间的延长,tPA/PAI-1值逐渐下降。结论:胰岛素和葡萄糖能够刺激内皮细胞分泌tPA和PAI-1抗原,在缺氧8 h以内,tPA/PAI-1值升高,纤溶活性升高,有利于局部自发性纤溶的发生。此作用可能是IGK治疗急性心肌梗死的机制之一。  相似文献   

8.
新生大鼠缺氧缺血性脑损伤tPA、PAI-1表达的动态变化   总被引:1,自引:0,他引:1  
目的:观察新生大鼠缺氧缺血性脑损伤(HIBD)中组织型纤溶酶原激活物(tPA)和1型纤溶酶原激活物抑制剂(PAI-1)表达变化的规律,探讨纤溶系统在缺氧缺血性脑损伤中的作用。方法:7日龄SD新生大鼠96只,随机分为2组:缺氧缺血性脑损伤组和假手术组。两组动物模型制备成功后3、6、12、24、36、48、72、96小时断头取脑,应用免疫组织化学及原位杂交方法检测缺氧缺血性脑损伤不同时间点t-PA、PAI-1表达的变化。结果:假手术组新生大鼠各脑区均有tPA、PAI-1蛋白及mRNA的弱表达,缺氧缺血性脑损伤组不同时间点t-PA、PAI-1二者表达呈不同的动态变化:tPA蛋白及mRNA 3小时开始表达增强,主要见于皮质和海马,神经元表达明显,血管表达较弱,48小时神经元及微血管内皮表达明显增强,72小时神经元表达明显减弱,微血管内皮见有明显阳性表达,之后表达减弱,3~96小时各时间点阳性着色神经元数目显著高于假手术组;PAI-1蛋白及mRNA 12小时表达有所增强,神经元和微血管内皮表达增多,72小时达高峰,12~96小时各时间点阳性着色神经元数目显著高于假手术组。结论:tPA和PAI-1参与HIBD的发病机制。  相似文献   

9.
睾酮对人血管内皮细胞纤溶活性影响及机制   总被引:1,自引:0,他引:1       下载免费PDF全文
目的:观察睾酮对人血管内皮细胞分泌纤溶酶原激活物(tPA)、纤溶酶原激活物抑制物1(PAI-1)的影响及其机制。方法: 将体外培养的人血管内皮细胞(HUVEC)分为5个浓度睾酮组及单纯培养基对照组,MTT实验观察睾酮对细胞生长及活性影响。ELISA 法测各组tPA、 PAI-1含量。用雄激素受体拮抗剂(flutamide)预处理细胞后重复实验。结果: 生理及略低于生理剂量睾酮(3×10-10 mol/L-3×10-8 mol/L)可明显促进tPA 分泌(P<0.01);而大剂量则使tPA 含量明显减少(P<0.01)。各睾酮组PAI-1含量均明显低于对照组(P<0.05)。Flutamide 能有效消除睾酮的上述作用。结论: 生理浓度睾酮通过雄激素受体促进tPA分泌,降低PAI-1浓度而增强纤溶系统活性,有利于防止血栓性疾病的发生。  相似文献   

10.
纤溶酶原激活物抑制因子-1(PAI-1)是组织型纤溶酶原激活物(t-PA)和尿型纤溶酶原激活物(u-PA)的特异性抑制剂。对PAI-1分子的结构与功能的认识,有助于了解PAI-1发挥抑制 作用的机理。本文综述了近年来对PAI-1蛋白分子结构与功能研究的进展,介绍了PAI-1分子中一些区域的作用以及影响PAI-1抑制活性的一些因子。  相似文献   

11.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

12.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

13.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

14.
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

15.
16.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

17.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

18.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

19.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

20.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

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