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1.
目的利用RNA干扰技术,在细胞、蛋白和基因水平上观察短双链RNA对柯萨奇病毒体外感染Hela细胞的增殖抑制作用、对病毒RNA复制和蛋白合成的影响。方法应用病毒致细胞病变作用保护实验、空斑形成减少实验、Western Blot、RT-PCR等方法,在体外检测其抗CVB3病毒作用。结果设计、合成的8条SiRNA中,针对基因组2B、VP4、2A、3C区的SiRNA-2、SiRNA-3、SiRNA-6、SiRNA-7具有不同程度的抑制病毒作用。其中,病毒基因组2B的SiRN.2作用效果最好,对Hela细胞CVB3感染72h后致细胞病变和空斑形成的抑制率为95%,抑制病毒蛋白的合成,病毒基因的复制水平也显著降低,在病毒0.1、0.01、0.001、0.0001 MOI感染水平上对CVB3致细胞病变作用的抑制率分别为30%、70%、88%和99%(48h)。结论针对CVB3基因组2B的SiRNA-2具有较强的抑制柯萨奇B3型病毒感染的作用。  相似文献   

2.
目的研究抗病毒药物利巴韦林体外抗肠道病毒(EV)的效果。方法采用细胞病变效应(CPE)法和MTT分析法,观察利巴韦林对肠道病毒(EV71、CAV16、CBV3、ECH011、EV84)的抑制作用。结果利巴韦林对Vero细胞的半数毒性浓度(TC50)为2.09mg/mL,0.2mg/mL浓度的利巴韦林对5种肠道病毒均有抑制作用,对CAV16、EV71、ECHO11、EV84、CBV3的抑制率分别为13%、27%、36%、23%、58%。对EV84、EV71病毒,利巴韦林浓度为0.1mg/mL时其抑制率为16.5%、29.5%;对CBV3病毒,利巴韦林抗病毒作用与其剂量呈正相关,半数有效浓度(IC50)为0.125mg/mL,治疗指数(TI)为16.72。结论利巴韦林在体外对肠道病毒具有抑制作用,对不同的肠道病毒其抑制效率不同,对CVB3的抑制率较高。  相似文献   

3.
目的 分析三七提取物(SE)对小鼠淋巴细胞体外活化、增殖以及对巨噬细胞产生NO的影响,探讨其免疫抑制作用的机制。方法 以多克隆刺激剂刀豆蛋白A(ConA)刺激淋巴细胞活化和增殖,利用荧光标记的单克隆抗体双染技术和流式细胞术检测SE对小鼠CD3^+T细胞CD69表达的影响;通过CFSE染色流式细胞术检测SE对淋巴细胞增殖的影响;用脂多糖(LPS)或淋巴细胞培养上清液(lymphocytes culture supernate,LCS)体外诱导小鼠腹腔巨噬细胞分泌NO,采用Griess试剂盒检测NO的水平。结果 在ConA刺激6h后小鼠T细胞活化率为59.79%,50、100μg/ml的SE可显著降低其活化率,分别为46.50%和37.73%(P〈0.01)。在培养72h后,不同浓度SE能明显抑制ConA诱导T细胞的增殖。SE在12.5~100μg/ml的浓度范围内对淋巴细胞培养上清和LPS诱导小鼠腹腔巨噬细胞NO的释放具有抑制作用(P〈0.01)。结论 三七提取物对小鼠淋巴细胞的活化、增殖有明显抑制作用,并能抑制巨噬细胞产生NO(P〈0.01)。  相似文献   

4.
应用RNAi技术沉默STAT3基因对乳腺癌MCF-7细胞的影响   总被引:3,自引:2,他引:3  
目的 探讨应用RNAi技术沉默信号转导子与转录活化子3(STAT3)基因对乳腺癌MCF-7细胞的影响。方法 应用RNAi技术,以psilencer1.0-U6-STAT3-siRNA重组质粒体外转染MCF-7细胞,采用MIT实验、流式细胞仪检测MCF-7转染前后细胞增殖、细胞周期和早期凋亡的变化,通过Western blotting及半定量RT-PCR检测STAT3基因不同水平的表达。结果 MTT实验、流式细胞仪的结果显示,重组质粒转染组的MCF-7细胞的增殖明显受到抑制,且出现凋亡现象;Western blotting及半定量RT-PCR结果显示,重组质粒转染组细胞的STAT3基因表达在蛋白及RNA水平上都显著低于对照组(P〈0.01),而空白对照组及空质粒组无明显差异(P〉0.05)。结论 应用RNAi技术沉默STAT3基因可以降低乳腺癌MCF-7细胞STAT3的表达,进而抑制细胞的生长、增殖及诱导细胞的凋亡。  相似文献   

5.
目的:检测妊高征患者血浆ET、CGRP及NO含量,探讨其与内皮细胞功能的关系及临床意义。方法:ET、CGRP及NO3项指标均采用放射免疫分析。结果:血浆ET、CGRP及NO水平正常妊娠组与正常非孕组比较差异无显著性(P〉0.05);轻度妊高征组与正常妊娠组比较也无显著性差异(P〉0.05);中及重度妊高征两组则3项指标与正常妊娠组比较均存在极显著性差异(P均〈0.01)。结论:妊高征患者血浆ET、CGRP和NO浓度的变化,为研究其发病机理提供了有价值的实验室依据。  相似文献   

6.
目的探讨中药黄芪多糖的体外抗人乳腺癌MCF.7细胞活性。方法实验分为空白对照组、黄芪多糖组和阳性对照组,黄芪多糖组MCF.7细胞给予不同浓度(2.5、5、10、20mg/L)的黄芪多糖,阳性对照组给予10gmol/L顺铂,空白对照组给予等体积培养基。48h后应用四甲基偶氮唑蓝(MTT)法测黄芪多糖对MCF-7细胞增殖抑制率,计算IC_50;吖啶橙(AO),溴化乙啶(EB)荧光染色法测定黄芪多糖对MCF-7细胞诱导凋亡作用;应用流式细胞仪分析黄芪多糖对MCF-7细胞凋亡和细胞周期的影响。结果在给予2.5、5、10、20mg/L黄芪多糖48h后,黄芪多糖呈浓度依赖性抑制MCF.7细胞的增殖(r=0.985,P〈0.05),抑制率分别为(4.14±2.96)%、(7.14±2.10)%、(20.13±2.33)%、(64.66±5.15)%,高于空白对照组0%,但4个不同浓度组的抑制率均低于阳性对照组(90.31±4.92)%。黄芪多糖48h的IC_50=16.83mg/L。随着黄芪多糖浓度的逐渐增高,MCF-7细胞中代表凋亡的玛瑙色逐渐增多,细胞核骤缩、核分裂,细胞形态呈现典型的凋亡特征。2.5、5、10、20mg/L黄芪多糖的凋亡率分别为(2.37±0.98)%、(6.76±1.31)%、(11.65±1.46)%、(20.75±2.68)%,高于空白对照组(1.14±1.25)%(均P〈0.05),但均低于阳性对照组(35.09±2.88)%(均P〈0.05)。与空白对照组比较,黄芪多糖以浓度依赖性诱导MCF-7细胞凋亡(r=0.991,P〈0.05),随浓度的增加,细胞凋亡率升高,但均低于阳性对照组。黄芪多糖随浓度的增加促使s期细胞比例逐渐升高,但低于空白和阳性对照组(均P〈0.05),使处于G_0-G_1期细胞的比例逐渐减少,仍高于空白和阳性对照组(均P〈0.05)。结论黄芪多糖抑制人乳腺癌MCF-7细胞增殖并诱导其凋亡,使MCF-7细胞生长增殖停滞在S期?  相似文献   

7.
酪氨酸激酶抑制剂对T淋巴细胞生物学特性影响的研究   总被引:2,自引:1,他引:1  
目的探讨酪氨酸激酶抑制剂(TKI)在体外对T淋巴细胞生物学特性的影响。方法应用尼龙毛柱法分选人外周血T淋巴细胞,加入植物血凝素和抗人CD3单克隆抗体体外培养;运用MTT法检测不同浓度的伊马替尼(imatinjb)、尼罗替尼(nilotib)对T细胞增殖的影响;酶联免疫吸附试验(ELISA)法检测其分泌的细胞因子浓度;通过流式细胞仪检测T细胞表面免疫活性标志;实时荧光定量PCR法检测各组T细胞信号分子P56^lck。mRNA的表达。结果伊马替尼、尼罗替尼对T淋巴细胞增殖活性有抑制作用(P=0),且呈浓度和时间依赖性;各处理组细胞因子IFN-γ、TNF-α、IL-4、IL-2浓度较对照组低(P=0.03),IL—10浓度在处理组与对照组无差异(P=0.53),且表面活性分子CD25和CD69明显减少(P=0.03,P=0.01),尼戮替尼处理组CD25、CD69表达更低(P=0.05,P=0);各处理组T细胞信号分子P56^lck。表达水平降低(P=0.03),而尼罗替尼处理组P56^lck。表达更低(P=0.04)。结论有效治疗浓度的伊马替尼、尼罗替尼在体外可能通过抑制T淋巴细胞受体P56^lck的表达进而抑制T细胞的增殖和活性。  相似文献   

8.
目的探讨SLE患者免疫功能紊乱与淋巴细胞凋亡信号传导途径异常之间的关系。方法应用流式细胞术测定SLE患者淋巴细胞表面Fas、FasL及细胞质中活化caspase-3的表达率,并测定凋亡细胞百分率(AnnexinV^+PI^-)和坏死细胞百分率(AnnexinV^+PI^+)。应用ELISA方法测定血清中抗核小体抗体浓度。结果与健康对照组相比,稳定期和活动期SLE患者组淋巴细胞中凋亡细胞和坏死细胞百分率均显著增加(P〈0.05),淋巴细胞表面Fas、FasL及细胞质中活化caspase-3的表达率也显著增加(P〈0.05)。与稳定期SLE患者组相比,活动期SLE患者组淋巴细胞中坏死细胞百分率显著增加(P〈0.05),凋亡细胞百分率略有增加但无统计学意义(P〉0.05)。活动期患者组淋巴细胞表面Fas、FasL以及细胞质中活化caspase-3的表达率略有增加但无统计学意义(P〉0.05)。活动期SLE患者组抗核小体抗体浓度显著高于健康对照组和稳定期患者组(P〈0.05)。SLE患者凋亡细胞百分率和活化caspase-3的表达率与补体C3浓度水平呈负相关关系(P〈0.05)。结论Fas信号传导通路在SLE患者淋巴细胞凋亡紊乱中发挥了重要作用。caspase-3的活化是早期提示淋巴细胞凋亡的重要信号。SLE患者淋巴细胞凋亡活化程度与疾病活动程度和免疫效应功能紊乱密切相关,而淋巴细胞凋亡异常程度与抗核小体抗体水平的高低密切相关。淋巴细胞凋亡加速在SLE患者免疫病理损伤加重和免疫细胞调控紊乱中扮演了重要角色。  相似文献   

9.
目的观察模拟微重力条件下实验性自身免疫性脑脊髓炎(EAE)大鼠淋巴细胞细胞功能的变化。方法尾根免疫MBP668-86建立EAE模型;12d时处死大鼠,分离培养淋巴结细胞;利用旋转式细胞培养系统进行模拟微重力培养;不同时间点,增殖实验检测细胞增殖、流式检测细胞凋亡、T细胞亚型、Th细胞亚群变化;酶联免疫吸附试验(ELISA)检测上清中细胞因子的变化。结果EAE淋巴细胞针对MBP68-86抗原特异性增殖,在培养20h,60h,80h时,增殖受到抑制(t=3.859,P〈0.01;t=5.933,P〈0.001;t=7.613,P〈0.001);40h时,增殖受到促进(t=4.015,P〈0.01)。培养24h时,微重力组坏死及凋亡细胞增高(t=3.998,P〈0.01;t=3.705,P〈0.01),Th细胞降低(t=4.111,P〈0.01),Th1、Th17和调节性T细胞(Treg)亚群比例升高(t=2.743,P〈0.05;t=4.362,P〈0.01;t=2.945,P〈0.05)。微重力培养40h时,IFN-γ,TNF-α浓度明显升高(t=4.056,P〈0.01;t=4.666,P〈0.01),TGF-β、IL-6、IL4、IL-17浓度明显降低(t=2.855,P〈0.05;t=2.644,P〈0.05;t=3.154,P〈0.05;t=2.732,P〈0.05)。结论除40h外,MBP668-86。特异性淋巴细胞增殖在模拟微重力环境中被抑制;细胞死亡增多、Th细胞减少,对EAE起重要作用的细胞因子的浓度改变。  相似文献   

10.
目的:探讨桔皮素对人肝癌细胞株SMMC-7721的抑制作用。方法:采用四唑盐(MTT)比色法观察不同浓度桔皮素对人肝癌细胞株SMMC-7721细胞增殖的影响,计算半数抑制浓度IC50;绘制细胞株SMMC-7721的生长曲线观察桔皮素对其增殖的影响。结果:MTT结果显示不同浓度的桔皮素对SMMC-7721的生长均有一定的抑制作用,同一时间,各浓度组与对照组相比均有统计学差异(P〈0.05);桔皮素浓度为0.24—30μg·mL。时,对SMMC-7721细胞在药物处理72小时后抑制率为3.85%~93.59%,且72小时的IG50为14.69—21.11μg·mL^-1。生长曲线结果提示,桔皮素对SMMC-7721细胞的抑制作用呈明显时效和量效关系。结论:桔皮素能抑制人肝癌细胞株SMMC-7721的增殖。  相似文献   

11.
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   

12.
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   

13.
Most bodily functions require the coordinated actions of complementary and supplementary paired muscle groups. Where this essential muscular cooperation is lacking, hollow organs may burst and others become literally screwed up, giving rise to many similar spastic diseases such as Torticollis, Twisted ovarian cyst, Torsion of the Testis, Volvulus of the intestines, Varicose Veins, Megacolon, Aortamegaly, Scoliosis, Erb's Palsy, Peyronie's Disease, Main-en-Griffe, Undescended Foot (Pes Cavus), Talipes, Strabismus. Spasm is “panenepidemic” and unclassified examples of Torsion Dystonia and Dyskinesia really are as common as debt and taxes.  相似文献   

14.
15.
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   

16.
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   

17.
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   

18.
Zusammenfassung Eine Reihe pathologischer Zustände bedingen Magnesiummangel. Zustände mit Hypermagnesämie sind ebenfalls bekannt, doch wesentlich seltener. Für den Kardiologen beachtenswert ist, daß unter Therapie mit bestimmten Diuretica bei Herzinsuffizienz, bei Herzinfarkt, Kardiomyopathie, Digitalisintoxikation und bestimmten Herzrhythmusstörungen Hypomagnesämie beobachtet wurde. Leider kann in der klinischen Routine nur ein extracelluläres Magnesiumdefizit durch Serumbestimmungen gemessen werden; über Magnesiummangel einzelner Organe kann nichts ausgesagt werden. Hinweise für Magnesiummangel geben aber neben der Messung des Serumspiegels Anamnese, klinischer Befund, bestimmte EKG-Veränderungen wie auch evtl. Hypokalämie, ein Zustand, bei dem sich oft — besonders bei Aldosteronismus — parallele Veränderungen zeigten.Tierexperimente deuten darauf hin, daß infarktähnliche Läsionen unter Magnesiummangel entstehen, doch ob Herzinfarkt beim Menschen durch Magnesiummangel ausgelöst werden kann, ist noch ungeklärt. In Leichenherzen zeigte sich im Infarktgebiet neben Calciumakkumulation signifikanter Magnesiumverlust, wobei unklar blieb, ob sich Ursache oder Folge des Infarktes widerspiegelten. Falls ein ursächlicher Zusammenhang besteht, ist er im Myokardstoffwechsel selbst zu suchen, wie bei der Alkoholkardiomyopathie, wo myokardialer Magnesiummangel zumindest als pathogenetischer Teilfaktor anerkannt wird. Andererseits versucht man aber auch Beziehungen zwischen Atherosklerose, Blutgerinnung und Hypomagnesämie herzustellen, in der Meinung, daß Magnesiummangel auch über den coronaren Pathomechanismus des Herzinfarktes wirken könnte. Sicher scheint, daß gewisse EKG-Veränderungen und Herzrhythmusstörungen durch einen irritierten Magnesiumhaushalt bedingt sein können, da sie bei Gabe bzw. Entzug von Magnesium verschwinden. Daß Magnesiummangel die Glykosidtoleranz verringert, wird tierexperimentell bestätigt. Unter Hypomagnesämie bewirkt Acetylstrophanthidin eher und länger Rhythmusstörungen als ohne, außerdem lassen diese sich durch Magnesiumgaben eliminieren. Da in gewissen Fällen spontane und digitalisinduzierte Herzrythmusstörungen durch Magnesiuminjektionen beseitigt wurden, scheint Magnesium als Therapeuticum angebracht. Einsatz verschiedener Magnesiumsalze bei Angina pectoris, degenerativen Herzerkrankungen und Herzinsuffizienz ohne geprüften und offensichtlich gestörten Magnesiumhaushalt ist fragwürdig, weil keine eindeutigen klinischen Erfolgsbeweise vorliegen. Immerhin mag es aber larvierte, durch Serumbestimmungen nicht erfaßbare Mangelzustände geben. Allgemein erscheint es aus kardiologischer Sicht ratsam, den Magnesiumhaushalt zu überwachen und in entsprechenden Fällen auszugleichen, um möglichen Myokardläsionen oder fatalen Herzrhythmusstörungen entgegenzuwirken.  相似文献   

19.
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   

20.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   

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