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探讨体外双轴拉伸应变对大鼠骨髓间充质干细胞(rBMSCs)向成骨细胞分化的影响。分离4周龄SD大鼠BMSCs,将P3~P4代rBMSCs接种于DMEM-LG完全培养基的双轴拉伸应变细胞培养小室中。当细胞生长至亚融合状态后,给予细胞施加拉伸应变,频率为1 Hz,应变幅度为1%、2%、5%,每个应变幅度均分别加载2h/d、4h/d、6h/d,连续作用3d。以未受拉伸应变的rBMSCs为空白对照组。以未受拉伸应变,含100nmol/L雌二醇(E2)培养的rBMSCs为阳性对照组。通过实时荧光定量PCR和Western blot方法检测各组rBMSCs的碱性磷酸酶(ALP)、Ⅰ型胶原(ColⅠ)、Runt相关转录因子-2(Runx2)、骨钙蛋白(OCN)mRNA和蛋白的表达量。实验结果表明:(1)E2组rBMSCs中Runx2、ColⅠ、ALP、OCN mRNA及蛋白表达量均明显高于空白对照组(P0.05);(2)1%拉伸应变组rBMSCs中ALP、Runx2mRNA和蛋白表达量均明显高于空白对照组(P0.05),但与E2组相比明显降低(P0.05);(3)2%拉伸应变组rBMSCs中ALP、ColⅠ、Runx2、OCN mRNA和蛋白表达量均明显高于空白对照组(P0.05),其中,加载时间4h/d组rBMSCs中ColⅠ、Runx2 mRNA和蛋白表达量明显高于E2组(P0.05);(4)5%拉伸应变组,加载时间2h/d、4h/d组rBMSCs中ALP、ColⅠ、Runx2mRNA和蛋白表达量均明显高于空白对照组(P0.05),与E2组相比,加载时间4h/d组的ColⅠ、Runx2mRNA和蛋白表达量也明显上调(P0.05)。本实验结果提示,雌二醇和体外双轴拉伸应变均可以诱导rBMSCs向成骨细胞分化,且拉伸应变幅度2%、加载时间4h/d时,促rBMSCs成骨分化的作用最强。  相似文献   

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目的 探讨葛根素是否通过下调miR-23a促进小鼠前成骨细胞增殖和分化。方法 将小鼠前成骨细胞MC3T3-E1分为对照组、葛根素组、葛根素+miR-NC组和葛根素+miR-23a过表达组,RT-qPCR检测细胞中miR-23a的表达,CCK-8法检测细胞增殖活性,碱性磷酸酶活性检测葛根素对细胞活力的影响,Western blot检测细胞中Runx2蛋白的表达。应用生物信息学和双荧光素酶报告基因实验验证miR-23a和Runx2的靶向调控关系。结果 与对照组相比,葛根素组MC3T3-E1细胞增殖活性增强,细胞中miR-23a表达降低,Runx2蛋白表达水平升高(P<0.05);与葛根素+miR-NC组相比,葛根素+miR-23a过表达组MC3T3-E1细胞增殖活性降低,细胞中Runx2蛋白表达降低(P<0.05);双荧光素酶报告基因实验证实miR-23a靶向负调控Runx2的表达。结论 葛根素促进小鼠前成骨细胞增殖和分化,机制可能与下调miR-23a进一步调控Runx2表达有关。  相似文献   

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目的:研究细胞外信号调节激酶(ERK)/转化生长因子β(TGF-β)/Sma和Mad相关蛋白(Smads)信号级联在左归丸含药血清干预成骨前体细胞系MC3T3-E1细胞增殖与分化中的作用。方法:以倍美力为阳性对照药,对Sprague-Dawley(SD)雌性大鼠灌服高、中、低剂量的左归丸混悬液,7 d后腹主动脉取血分离含药血清。采用噻唑蓝(MTT)法检测左归丸含药血清对MC3T3-E1细胞的增殖作用,采用改良钙钴染色法检测碱性磷酸酶(ALP)表达,采用茜素红染色法检测钙化结节,采用Western blotting法检测核结合因子α1(Cbfα1)和Ⅰ型胶原(ColⅠ)蛋白表达,采用real-time RT-PCR法检测TGF-β1、Smad4和Smad2 mRNA表达。结果:左归丸含药血清对MC3T3-E1细胞的促增殖作用呈剂量和时间相关性,其中以低剂量且体积分数为15%作用48 h后对MC3T3-E1的促增殖作用最大;左归丸含药血清能促进MC3T3-E1细胞ALP表达,增强细胞基质钙化,提高Cbfα1和ColⅠ蛋白分泌,上调TGF-β1、Smad4和Smad2 mRNA表达;加入ERK1/2信号通路特异性阻滞剂PD98059后,MC3T3-E1细胞增殖降低,ALP表达下降,细胞基质钙化减弱,Cbfα1和ColⅠ蛋白分泌降低,Smad4和Smad2 mRNA表达下调,TGF-β1 mRNA表达进一步上调。结论:左归丸可能通过干预ERK/TGF-β/Smads信号级联而调控成骨细胞的增殖和分化,这可能是其防治骨质疏松症的机制之一。  相似文献   

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目的 探究周期性牵拉对小鼠胚胎成骨细胞MC3T3-E1迁移功能的影响及其相关机制.方法 使用应变加载系统对体外培养的MC3T3-E1细胞施加15%幅度的牵拉,模拟细胞体内受力情况.使用划痕愈合实验检测MC3T3-E1细胞的迁移功能,使用蛋白免疫印迹法检测Runx2表达情况,使用RNA干扰技术特异性降低Runx2表达量....  相似文献   

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目的 研究低强度高频率振动(low-magnitude high-frequency vibration, LMHFV)对成骨细胞生物学特性的影响。 方法 建立LMHFV加载MC3T3-E1细胞模型,观察不同频率LMHFV对MC3T3-E1细胞OPG/RANKL浓度比的影响,获得OPG/RANKL浓度比最高的频率(F)为后续研究频率;以0 Hz为对照,观察LMHFV对MC3T3-E1细胞碱性磷酸酶 (ALP)、骨钙素(OCN) mRNA和蛋白活性,及钙化结节形成的影响;LMHFV加载形成的条件培养液(CMF)孵育RAW264.7细胞,观察CMF对破骨细胞抗酒石酸酸性磷酸酶(TRAP)染色、多核破骨细胞形成、TRAP mRNA及蛋白活性的影响;观察LMHFV对MC3T3-E1细胞环氧化酶2(COX-2)蛋白水平的表达及COX-2抑制剂NS-398对LMHFV影响MC3T3-E1细胞分化的作用。 结果 30 Hz LMHFV获得OPG/RANKL浓度比最高,促进ALP、OCN mRNA及蛋白活性增加,增加钙化结节形成。30 Hz LMHFV形成的CM抑制RAW264.7细胞向多核破骨细胞分化,抑制TRAP mRNA及活性;LMHFV可诱导COX-2蛋白水平增加,NS-398能抑制LMHFV促进成骨细胞分化。 结论 30 Hz的LMHFV对MC3T3-E1细胞OPG/RANKL浓度比及成骨分化具有积极的影响,通过调控成骨细胞OPG/RANKL浓度比间接抑制骨吸收,COX-2通路参与了LMHFV对成骨细胞生物学特性的调节作用。  相似文献   

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目的:研究盐酸小檗碱对小鼠前成骨细胞系MC3T3-E1分化与矿化的调控作用及其机制。方法:MC3T3-E1细胞给予不同浓度(0、1、5、10和20 mg/L)的盐酸小檗碱刺激3 d,CCK-8法检测细胞活性。不同浓度的盐酸小檗碱分别干预3 d和7 d,检测细胞碱性磷酸酶(ALP)活性。进一步将实验随机分为4组:对照组、盐酸小檗碱组、盐酸小檗碱+LY249002(PI3K/Akt通路抑制剂)组及LY249002组。干预2 d后,采用real-time PCR检测成骨细胞分化相关因子ALP、骨钙素(OCN)、骨桥蛋白(OPN)及Runt相关转录因子2(Runx2)的mRNA表达情况,采用Western blot检测PI3K/Akt信号通路相关蛋白p-Akt的表达水平。将MC3TC-E1细胞用矿化培养基诱导21 d,茜素红染色检测其矿化情况。结果:与对照组相比,不同浓度的盐酸小檗碱对细胞活性的影响没有明显差异;不同浓度的盐酸小檗碱处理MC3T3-E1细胞后ALP活性有不同程度升高。Real-time PCR结果表明,盐酸小檗碱(5 mg/L)促进ALP、OCN、OPN及Runx2的mRNA表达(P 0. 01),而LY294002能抑制这些分化相关因子的表达。Western blot检测结果表明,盐酸小檗碱(5 mg/L)促进p-Akt蛋白的表达(P 0. 01),其作用被LY249002抑制。茜素红染色发现盐酸小檗碱组矿化明显,但LY294002能抑制盐酸小檗碱的促进作用。结论:盐酸小檗碱可以促进小鼠前成骨细胞的分化与矿化,其机制可能与其激活PI3K/Akt信号通路有关。  相似文献   

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背景:Atf7ip是否参与成骨分化的调控尚未明确,研究其对成骨分化的影响及具体机制具有重要意义。目的:探讨Atf7ip对骨形态发生蛋白2促小鼠胚胎成骨细胞前体细胞(MC3T3-E1)成骨分化的影响。方法:将体外培养的MC3T3-E1细胞分为正常组、干扰组(NC-si RNA组、Atf7ip-si RNA组)、高表达组(CMV-VC组、CMV-Atf7ip组),转染处理24 h,然后使用200 ng/mL骨形态发生蛋白2分别处理0,12,24,48 h,qRT-PCR检测各组细胞中Atf7ip、碱性磷酸酶、骨钙素、Ⅰ型胶原α1的mRNA表达水平,Western blot检测成骨分化标记分子Sp7、Runx2的蛋白表达以及Atf7ip结合分子SETDB1、组蛋白H3、H3K9me3甲基化的表达,并进行碱性磷酸酶活性分析。结果与结论:(1)随骨形态发生蛋白2处理时间增加,Atf7ip的蛋白及mRNA表达减少,而Sp7、Runx2的蛋白表达和骨钙素、碱性磷酸酶的mRNA表达显著增加(P <0.05);Atf7ip结合分子SETDB1的蛋白表达并无明显改变;(2)与NC-siRNA组比较,...  相似文献   

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目的: 观察淫羊藿素(ICT)对MC3T3-E1 subclone 14前体成骨细胞株增殖、分化的影响,以及雌激素受体(ER)和骨形态发生蛋白(BMP)信号在分化中的作用。方法: WST-8、BrdU法检测ICT对MC3T3-E1 subclone 14细胞活力和增殖的影响;ICI182780阻断ER受体信号后,检测ICT和noggin对MC3T3-E1 subclone 14细胞碱性磷酸酶(ALP)活性、I型胶原(Col I)和骨钙素(BGP)的影响;实时荧光PCR检测ICT对BMP-2、4、7 mRNA表达的影响;Western blotting检测ER受体信号阻断后,ICT对Smad1/5/8蛋白磷酸化的影响。结果: ICT(0.1 μmol/L、1 μmol/L)可以提高MC3T3-E1 subclone 14细胞ALP、Col I、BGP和矿化结节数量(P<0.01或P<0.05),表明ICT有促分化的作用,但对细胞活力和增殖指数无明显影响;阻断ER受体信号后,ICT促分化作用明显下降(P<0.01);ICT可以提高BMP-2、4 mRNA的表达(P<0.01),但对BMP-7 mRNA无作用(P>0.01);阻断ER信号后,ICT 促Smad1/5/8磷酸化明显减弱(P<0.01)。进一步阻断BMP/Smad信号可以抑制ICT促分化的作用(P<0.01)。结论: ICT可以通过ER受体激活BMP/Smad信号通路,进而促进MC3T3-E1 subclone 14细胞的分化。  相似文献   

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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   

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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   

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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   

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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   

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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   

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《Human immunology》2022,83(11):739-740
Georgia (or Sakartvelo in its own language) is a South Caucasus Mts. country with its easternmost part is enigmatically named Iberia, like the Iberian Peninsula, which may refer to rivers “Kura” and “Ebro” or their valleys respectively. Most of their inhabitants speak Georgian which is included within Dene-Caucasian group and Usko-Mediterranean subgroup of languages. The latter includes Basque, Berber, ancient Iberian-Tartessian, Etruscan, Hittite, Minoan Lineal A and others. In the present paper, HLA class II -DRB1 and -DQB1 alleles has been studied and extended haplotypes calculated. Most frequent haplotypes are also of Mediterranean origin (i. e.: (A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*51)-DRB1*13:01-DQB1*06:03, or (A*24-B*35)-DRB1*01:01-DQB1*05:01) and DA genetic distances show that closest world populations to Georgians are Mediterraneans. Georgians also show common extended haplotypes ((A*02-B*51)-DRB1*11:01-DQB1*03:01, (A*02-B*13)-DRB1*07:01-DQB1*02:01 and (A*03-B*35)-DRB1*11:01-DQB1*03:01) with Svan people, a secluded population in North Georgia mountains. We can conclude that Georgians belong to a very old Mediterranean substratum according to both linguistics (Usko Mediterranean languages) and HLA genetics.  相似文献   

18.
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   

19.
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   

20.
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   

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