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1.
目的探讨基质细胞衍生因子-1α(SDF-1α)受体CXCR4、CXCR7在骨髓间充质干细胞(BMSCs)中蛋白和mRNA的表达;及SDF-1α/CXCR4/CXCR7轴对BMSCs迁移作用的可能机制。方法体外培养大鼠BMSCs,流式细胞术鉴定细胞表面抗原CD29、CD44和CD34。应用CXCR4特异性拮抗剂AMD3100及CXCR7中和抗体分别阻断CXCR4及CXCR7,通过Western blotting和RT-PCR分别检测BMSCs蛋白和mRNA的表达变化;Transwell法检测细胞迁移能力。本次实验分为单纯BMSCs组(A)、AMD3100预处理BMSCs组(B)、CXCR7中和抗体预处理BMSCs组(C)及AMD3100+CXCR7中和抗体预处理BMSCs组(D)。结果经鉴定第3代大鼠BMSCs中CD29和CD44均呈阳性表达,而CD34表达阴性。BMSCs中CXCR4、CXCR7蛋白和mRNA均有表达。与A组相比,B组及D组CXCR4及CXCR7蛋白表达明显受到抑制(P0.05),C组只有CXCR7蛋白表达降低(P0.05);各组CXCR4 mRNA和CXCR7 mRNA的表达差异均无显著性。SDF-1α可以诱导BMSCs迁移,与0μg/L组相比,10μg/L组和100μg/L组穿膜细胞数均显著增多(P0.01),与10μg/L组相比,100μg/L组穿膜细胞数亦明显增多(P0.01);AMD3100和CXCR7中和抗体均能抑制BMSCs的迁移作用(P0.05),当两者同时作用时,抑制效应更为显著(P0.05)。结论 BMSCs共表达CXCR4、CXCR7蛋白及mRNA;BMSCs的迁移具有SDF-1α浓度依赖性;SDF-1α/CXCR4/CXCR7轴介导BMSCs的迁移作用,CXCR4受体和CXCR7受体对BMSCs的迁移可能具有协同促进作用。  相似文献   

2.
目的:探讨黄芪甲苷(AS-IV)对内皮祖细胞(EPCs)中CXC趋化因子受体4(CXCR4)和基质细胞衍生因子1α(SDF-1α)的调控作用及其作用机制。方法:体外培养大鼠骨髓源性EPCs,观察应用AS-IV及CXCR4的特异性阻断剂AMD3100后EPCs的增殖、黏附、迁移、凋亡和管状结构形成能力的变化,并分析AS-IV对EPCs中SDF-1α及CXCR4的mRNA和蛋白,以及p-CXCR4蛋白水平变化的影响。结果:AS-IV可以显著提升EPCs的增殖、黏附、迁移和管状结构形成能力,减轻EPCs的凋亡,上调EPCs中SDF-1α和CXCR4的mRNA和蛋白及p-CXCR4蛋白的水平(P0.05);AMD3100可以阻断AS-IV对CXCR4的mRNA和蛋白及p-CXCR4蛋白水平的上调作用,但不影响AS-IV对SDF-1α的mRNA和蛋白水平的上调作用。结论:AS-IV可能通过调控EPCs中SDF-1α/CXCR4的表达而增强EPCs的生物学作用。  相似文献   

3.
目的:探讨基质细胞衍生因子-1α(SDF-1α)对骨髓间充质干细胞(BMSCs)在SD大鼠脑缺血后迁移至脑损伤区的影响。方法:构建大脑中动脉阻塞的脑缺血模型;50只大鼠随机分为脑缺血PBS对照组、脑缺血MSCs治疗组。将腺病毒携带的增强型绿色荧光蛋白(EGFP)标记的MSCs,在脑缺血1d后经尾静脉注射入大鼠体内;用实时定量PCR检测缺血半暗带区基质细胞衍生因子-1α(SDF-1α)的分泌;用流式细胞仪检测骨髓间充质干细胞上CXCR4的表达率;用荧光共聚焦显微镜扫描显示骨髓间充质干细胞的迁移。结果:GFP转染率大约87%转染骨髓间充质干细胞;实时定量PCR显示大鼠海马分泌的SDF-1α在1 d时达到峰值,1-14 d一直维持在较高的水平,14 d后开始缓慢下降,而皮质分泌的SDF-1α在第3 d开始缓慢上升,14 d才达到峰值;流式细胞仪检测BMSCs表面的CXCR4有14%;GFP标记的BMSCs移植后6 h发现聚集在大脑中动脉起始处(嗅球),在第3 d后在丘脑等缺血半暗带区,在14 d后皮质处的GFP+BMSCs已有明显的增加。结论:损伤组织SDF-1α浓度的升高与骨髓间充质干细胞迁移的增加可能存在一定的关系。  相似文献   

4.
目的:探讨SDF-1α/CXCR4轴对胰腺癌细胞迁移和侵袭能力的影响及其作用机制。方法:应用RT-qPCR检测4种胰腺癌细胞株CXCR4 mRNA的表达。Transwell实验检测外源性SDF-1α及其受体CXCR4靶向抑制剂AMD3100对胰腺癌细胞迁移和侵袭能力的影响。MTS法检测外源性SDF-1α及AMD3100对胰腺癌细胞活力的影响。Western blot法检测外源性SDF-1α及AMD3100对胰腺癌细胞上皮-间充质转化(EMT)相关标志物表达的影响。结果:(1) 4种胰腺癌细胞株均不同程度地表达CXCR4 mRNA,其中PANC-1细胞株表达量最高。(2)外源性SDF-1α可增强PANC-1细胞的迁移和侵袭能力,该作用可被AMD3100所阻断。(3)外源性SDF-1α处理PANC-1细胞72 h可增强细胞活力,该作用可被AMD3100阻断。(4)外源性SDF-1α通过上调SNAIL和TWIST促使PANC-1细胞发生EMT,该作用可被AMD3100所阻断。结论:SDF-1/CXCR4轴通过促进胰腺癌细胞发生EMT而促进肿瘤迁移和侵袭。  相似文献   

5.
目的探讨低氧刺激在骨髓间充质干细胞(bone marrow mesenchymal stem cells, BMSC)向心肌细胞谱系分化过程中对心肌素(Myocardin)表达的影响及机制。方法分离Sprague Dawley大鼠股骨BMSC,磁激活细胞分选法获得c-Kit~+细胞亚群。分别用HIF-1α过表达慢病毒感染或物理性低氧(2%O_2)刺激c-Kit~+ BMSC,定量RT-PCR检测HIF-1α、Myocardin和心肌细胞分化基因(Nkx2.5、cTnT)的mRNA水平,免疫荧光检测Myocardin和cTnT蛋白表达,双荧光素酶报告基因法检测HIF-1α对Myocardin启动子活性的影响。结果 HIF-1α过表达慢病毒感染和物理性低氧刺激均诱导c-Kit~+BMSC中Myocardin和心肌细胞分化标志基因Nkx2.5、cTnT的表达水平明显增高。shRNA抑制Myocardin后一定程度上减弱低氧诱导的c-Kit~+ BMSC心肌细胞样分化。HIF-1α可直接上调Myocardin启动子活性。结论低氧刺激可通过HIF-1α直接上调Myocardin表达,进而促进c-Kit~+BMSC向心肌样细胞分化。  相似文献   

6.
目的:探讨基质细胞衍生因子-1(stromalcell-derivedfactor-1,SDF-1)/CXC趋化因子受体4(CXCchemokinereceptor4,CXCR4)轴调控间充质干细胞定向分化、修复缺氧缺血性脑损伤的作用。方法:大鼠间充质干细胞(ratmesenchymalstemcells,rMSCs)经缺氧培养不同时点(0h、6h、12h、24h、48h、72h)或SDF-1α(10μg/L)孵育后,采用RT-PCR、Westernblotting和流式细胞术检测其表面CXCR4表达的变化;建立大鼠缺氧缺血性脑损伤模型,运用RT-PCR和Westernblotting检测造模后不同时点(1d、3d、5d、7d、14d、21d)大鼠脑部海马组织中SDF-1αmRNA转录和蛋白表达的改变情况;用AMD3100(CXCR4拮抗剂)拮抗rMSCs表面CXCR4后,免疫细胞化学和Westernblotting检测rMSCs诱导向神经细胞分化中神经元特异性烯醇化酶(neuron-specificenolase,NSE)和胶质纤维酸性蛋白(glialfibrillaryacidicprotein,GFAP)等神经细胞特异性标志物的阳性率及表达变化情况。结果:低氧培养6h及12h的rMSCsCXCR4mRNA及蛋白表达水平均较常氧培养组明显增加(P<0.01),10μg/LSDF-1α孵育后rMSCs的CXCR4表达水平明显增加(P<0.01);缺氧缺血性脑损伤模型的大鼠脑内SDF-1α蛋白表达显著增加(P<0.01);5mg/LAMD3100处理后的rMSCs在向神经细胞诱导分化中NSE和GFAP蛋白的表达明显减少。结论:微小剂量的SDF-1α可诱导低氧培养的rMSCs表面CXCR4的表达,而在缺氧缺血性脑损伤模型的大鼠脑内SDF-1α表达增加,从而使SDF-1/CXCR4轴的生物学效应得以增强;CXCR4拮抗的rMSCs在分化中神经细胞特异性标志物NSE和GFAP的表达降低,表明SDF-1/CXCR4轴在rMSCs定向神经分化修复缺血缺氧脑损伤中具有重要的调控作用。  相似文献   

7.
目的 研究心复康含药血清对骨髓干细胞(BMSCs)中间质源性细胞因子α(SDF-1α)mRNA表达和蛋白分泌的影响.方法 采用全骨髓培养法分离和扩增BMSCs,并用流式细胞仪进行鉴定.以定量PCR(q-PCR)和酶联免疫吸附测定法(ELISA)分别检测含药血清作用后BMSCs中SDF-1α mRNA表达和蛋白分泌的改变情况.结果 经心复康含药血清作用72 h后,SDF-1α mRNA的表达量明显增加,实验组约为对照组的200倍(P<0.05);SDF-1α蛋白分泌量增加近1倍(P<0.05),其中实验组为(277.561 1±15.651 8)pg/ml,对照组(153.107 1±14.765 1)pg/ml.结论 全骨髓培养法可获得高纯度的BMSCs,含药血清可明显促进SDF-1αmRNA的表达及其蛋白分泌.  相似文献   

8.
目的 观察基质细胞衍生因子1(SDF-1)与骨髓间充质干细胞(BMSC)迁移及哮喘大鼠气道炎症的相关性。方法 取24只清洁级SD大鼠,随机均分为正常对照组、模型组、BMSC组;除对照组外,其余两组予卵清蛋白致敏激发制备哮喘模型,BMSC组于造模完成当天由尾静脉注射1 mL 106个BMSC。采用HE染色观察肺组织病理形态变化;Wright-Giemsa染色,光镜下计数支气管肺泡灌洗液(BALF)中各种炎细胞数量;ELISA检测BALF中白细胞介素4(IL-4)、IL-5、IL-13、IgE、IgG1、IgG2a含量;反转录PCR检测肺组织中SDF-1、信号转导子与转录激活子6(STAT6)的mRNA表达;免疫荧光细胞化学染色检测支气管上皮细胞中SDF-1的蛋白表达;Western blot法检测肺组织SDF-1、STAT6蛋白水平。结果 与对照组相比,模型组BALF中炎细胞计数及IL-4、IL-5、IL-13、IgE、IgG1、IgG2a含量显著升高;肺组织SDF-1、STAT6 mRNA和蛋白表达量显著升高;支气管上皮细胞SDF-1表达明显升高。与模型组相比,B...  相似文献   

9.
目的探讨miR-150对糖尿病肾病小鼠骨髓间充质干细胞(MSCs)中趋化因子受体4(CXCR4)蛋白表达的影响。方法提取糖尿病肾病(DN)小鼠与正常小鼠MSCs,通过成骨、成脂诱导及表面分子的特征鉴定MSCs;通过RT-PCR检测DN小鼠与正常小鼠MSCs中miR-150的表达情况;Western blot检测CXCR4和基质细胞衍生因子-1(SDF-1)蛋白的表达;Transwell实验检测细胞迁移能力。结果 MSCs诱导分化为脂肪细胞和骨细胞,并且其CD29(97.6%±2.2%)和CD90(99.1%±0.6%)表达阳性,CD45呈阴性表达(17.3%±4.5%),符合干细胞特性。miR-150在DN组MSCs中呈低表达(P0.05),在正常小鼠MSCs中,抑制miR-150表达后,CXCR4蛋白表达明显增加;过表达miR-150后,CXCR4及SDF-1的表达显著降低(P0.05)。结论 DN组MSCs中miR-150表达异常可能是其表达迁移相关蛋白异常的重要原因。  相似文献   

10.
目的:评价病毒巨噬细胞炎性蛋白ⅡN端肽(NT21MP)是否通过干扰SDF-1α/CXCR4信号抑制人乳腺癌细胞株SKBR3细胞的趋化作用。方法:以RT-PCR和免疫组化检测SKBR3和MCF-7两种人乳腺癌细胞中CXCR4的表达;用细胞转移实验检测在NT21MP存在或缺乏的情况下SDF-1α诱导SKBR3细胞的趋化作用;以Fluo3/AM为细胞内游离钙离子的荧光指示剂,用激光扫描共聚焦显微镜测定NT21MP对SDF-1α诱导SKBR3细胞内游离钙浓度的影响;Western blot分析ERK1/2和FAK蛋白的磷酸化水平变化。结果:相对于MCF-7细胞,SKBR3细胞中CXCR4蛋白表达水平较高;经SDF-1α处理后,SKBR3的迁移能力提高,CXCR4抑制剂AMD3100可有效抑制SKBR3细胞的迁移,细胞经NT21MP预处理后,可剂量依赖性地抑制SKBR3细胞的迁移(P<0.05);NT21MP也可抑制由SDF-1α诱导的细胞内Ca2+峰值(P<0.05),而钙离子浓度升高是SKBR3细胞迁移的重要信号之一;另外,相对于阴性对照组,NT21MP也可下调SDF-1α诱导的SKBR3中信号蛋白ERK1/2和FAK的磷酸化水平(P<0.05)。结论:NT21MP可抑制SDF-1α诱导的SK-BR3细胞的迁移,可能与其上游钙离子释放和ERK1/2及FAK磷酸化阻断信号有关。  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.
15.
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   

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.
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   

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.
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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