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1.
研究下调骨桥蛋白(osteopontin,OPN)对人U251胶质瘤细胞在裸鼠体内生长的影响并探讨其对胶质瘤生长、侵袭的可能机制.应用RNA干扰技术,将OPN基因的慢病毒干扰载体LV-OPNshRNA感染U251细胞.将对照和试验组U251细胞分别接种裸鼠,建立裸鼠荷瘤模型.3周后测量肿瘤的体积、瘤重并做肿瘤组织病理切片分析;利用RT-PCR和免疫印迹法检测OPN、尿激酶型纤维蛋白酶原激活物(uPA)、基质金属蛋白酶(MMP-2、MMP-9)的mRNA和蛋白表达;免疫组化法检测肿瘤组织微血管密度和血管内皮生长因子(VEGF)表达情况. 经OPN的RNA干扰后,能显著降低肿瘤组织OPN mRNA水平及蛋白表达,有效抑制肿瘤细胞生长及侵袭能力, 肿瘤体积及重量的减小有统计学意义(P<0.05).感染组uPA、MMP-2和MMP-9的mRNA和蛋白表达明显减少, 肿瘤组织的MVD值和VEGF的表达均显著降低.上述结果表明,抑制OPN的表达能明显抑制人U251胶质瘤细胞在裸鼠体内的生长和侵袭,OPN可能通过激活uPA、MMP-2和MMP-9等蛋白酶降解细胞外基质和促进肿瘤血管生成,参与胶质瘤的生长.  相似文献   

2.
李静  陈军  钱彦方  杜挺媛  张舒  孙喜庆 《生物磁学》2012,(28):5415-5419,5433
目的:观察模拟微重力(MMG)致人脐静脉内皮细胞(HUVECs)微管骨架结构的改变,并对MMG作用后细胞的增殖等功能进行评价。方法:酶消化法原代培养HUVECs,随机分为2D.clinostat干预的MMG培养组与NG对照培养组,均培养48h;倒置显微镜下观察细胞形态,细胞计数及流式细胞术分析细胞增殖、凋亡及细胞周期变化。结果:所培养的HUVECs细胞并经流式细胞术鉴定证实;MMG干预48h使大量的微管蛋白发生解聚,微管的网状结构已经模糊不见,随之代替的是崩解的微管小聚体;MMG可使HUvECs增殖明显抑制,细胞周期抑制于G2/M期(G2/M:MMG,27.6%;NG,18.1%;P〈0.05),然而细胞并没有发生明显凋亡。结论:MMG可显著影响HUVECs的形态与细胞骨架结构并抑制其增殖功能,HUVECs的增殖抑制可能与紊乱的微管结构密切相关。  相似文献   

3.
目的:研究三氧化二砷(As2O3)在体外对胶质瘤U251细胞侵袭迁移及金属基质蛋白酶2(MMP2)表达的影响.方法:采用台盼兰法(MTT法)观察As2O3对U251细胞粘附能力的影响;Transwell侵袭小室测定法检测As2O3对U251细胞侵袭能力的影响;明胶酶谱实验和逆转录-聚合酶链反应(RT-PCR)方法观察As2O3对金属基质蛋白酶2(Matrix metalloproteinase2,MMP2)在U251细胞中表达的影响.结果:As2O3能够降低U251细胞粘附能力,Transwell实验中药物处理组穿膜细胞数明显低于对照组(P<0.01),As2O3不但降低MMP2前体蛋白的表达,而且影响其mRNA的表达.结论:As2O3能够有效抑制胶质瘤U251细胞的侵袭迁移,其作用机制可能与As2O3下调胶质瘤U251细胞中MMP2的表达有关.  相似文献   

4.
梁元  刘耀华  郑天虎  赵世光 《生物磁学》2011,(Z1):4662-4664
目的:研究三氧化二砷(As2O3)在体外对胶质瘤U251细胞侵袭迁移及金属基质蛋白酶2(MMP2)表达的影响。方法:采用台盼兰法(MTT法)观察As2O3对U251细胞粘附能力的影响;Transwell侵袭小室测定法检测As2O3对U251细胞侵袭能力的影响;明胶酶谱实验和逆转录-聚合酶链反应(RT-PCR)方法观察As2O3对金属基质蛋白酶2(Matrix metalloproteinase2,MMP2)在U251细胞中表达的影响。结果:As2O3能够降低U251细胞粘附能力,Transwell实验中药物处理组穿膜细胞数明显低于对照组(P<0.01),As2O3不但降低MMP2前体蛋白的表达,而且影响其mRNA的表达。结论:As2O3能够有效抑制胶质瘤U251细胞的侵袭迁移,其作用机制可能与As2O3下调胶质瘤U251细胞中MMP2的表达有关。  相似文献   

5.
人巨细胞病毒(human cytomegalovirus,HCMV)在神经胶质瘤细胞中的复制水平不一,其机制尚不清楚。本研究通过下调转录激活因子5(ATF5)在神经胶质瘤细胞中的表达,检测HCMV感染神经胶质瘤细胞后病毒复制水平的变化。首先用HCMV AD169(MOI=5)分别感染U87、SY5Y及A172细胞,观察细胞形态变化,分别在24、48、72、96、120 h取各时间点上清液检测病毒滴度;Real-time PCR检测HCMV即刻早期基因(IE2)、早期基因(UL44)、晚期基因(UL99)及ATF5的表达情况;Western-blot检测病毒基因编码蛋白及ATF5表达的情况。结果显示HCMV在U87、SY5Y细胞中复制水平与病毒在A172细胞中复制水平相比,U87、SY5Y细胞组明显高于A172细胞组(P0.05),ATF5表达在U87、SY5Y细胞组与A172细胞组相比,U87、SY5Y细胞组ATF5表达明显高于A172组(P0.05);利用慢病毒介导的RNA干扰技术下调ATF5在U87、SY5Y细胞的表达,用HCMV感染细胞检测病毒基因及蛋白的表达,结果ATF5表达下调可抑制HCMV的复制(P0.05)。以上结果表明,在胶质瘤细胞中下调ATF5表达水平可以抑制HCMV的复制水平。  相似文献   

6.
研究人巨细胞病毒(HCMV)感染对神经胶质瘤U87细胞自噬的影响。通过观察微管相关蛋白1轻链3(LC3)、自噬相关基因Beclin1及其蛋白表达的变化,从而探讨HCMV与神经胶质瘤发生、发展的关系及意义。用HCMV AD169(MOI=5)感染神经胶质瘤U87细胞,同时将未感染HCMV的U87细胞作为对照组。分别在6、12、24、48 h用RT-PCR检测Beclin1的表达,Western-blot和免疫荧光检测Beclin1和LC3编码蛋白的表达,最后用CCK-8检测细胞的增殖活性。结果显示,HCMV感染的U87细胞LC3-II蛋白表达水平逐渐下降(P<0.05);同时,HCMV感染的U87细胞Beclin1基因及蛋白的表达水平也逐渐下降(P<0.01),且HCMV感染U87细胞增殖显著(P<0.01)。以上结果表明,HCMV感染抑制胶质瘤U87细胞自噬,并会引起Beclin1表达水平下调,进而导致胶质瘤细胞增殖。  相似文献   

7.
目的:探讨微波消融治疗骨肉瘤对其肺转移的影响及可能机制。方法:用含有1×10~7个大鼠源骨肉瘤UMR106细胞的悬液于SD大鼠右下肢皮下注射建立骨肉瘤移植模型,将其随机分为对照组和消融组。消融组大鼠肿瘤予以微波消融治疗10 min,50℃,空白对照组大鼠模拟消融10 min,0℃,检测和比较两组大鼠肿瘤直径变化,于治疗15天后处死大鼠,取大鼠肿瘤及肺组织,通过HE染色以及免疫组化检测基质金属蛋白酶(Matrix metalloproteinase,MMPs)及其拮抗因子(Tissue inhibitors metalloproteinase),即MMP-2、MMP-9及TIMP-2的表达。结果:消融组大鼠肿瘤直径明显小于对照组大鼠肿瘤直径,消融组大鼠肿瘤组织及肺组织MMP-2及MMP-9的阳性表达均显著高于对照组(P0.05),而TIPM-2的阳性表达则明显低于对照组(P0.05)。结论:微波消融技术治疗骨肉瘤可以抑制骨肉瘤细胞的增殖,甚至引起细胞凋亡,并且通过上调MMP-2、MMP-9以及下调TIMP-2的表达,可能会提高其远处转移发生的风险。  相似文献   

8.
为探讨去整合素-金属蛋白酶17(disintegrin and metalloproteinase 17,ADAM17)对人胶质瘤细胞增殖和迁移的影响及其调控机制,该研究用ADAM17 sh RNA质粒转染ADAM17高表达的胶质瘤细胞U87MG、U251MG,用过表达ADAM17载体转染ADAM17低表达细胞SW1783,q-PCR和Western blot检测ADAM17表达水平的变化,同时检测ADAM17和Hippo信号通路中相关蛋白质表达水平,CCK-8法分析细胞增殖能力并绘制生长曲线,划痕实验检测细胞迁移率。结果表明,下调ADAM17后,U87MG、U251MG细胞增殖和迁移能力减弱,而Hippo信号通路中MST2、p-MOB1、p-YAP蛋白表达水平升高;上调ADAM17后,SW1783细胞增殖和迁移能力增强,而MST2、p-MOB1、p-YAP蛋白表达水平降低。结果说明,ADAM17在脑胶质瘤细胞的增殖和迁移中发挥了重要作用,这可能是通过抑制Hippo信号通路来实现的,MST2被抑制,p-MOB1水平降低,从而YAP的磷酸化水平也降低,促进了胶质瘤细胞的增殖和迁移。  相似文献   

9.
摘要 目的:探讨人参皂苷Rh2对大鼠C6胶质瘤细胞Siah-1、突触素(Synaptophysin)、基质金属蛋白酶-9(MMP-9)血管内皮生长因子(VEGF)表达的影响。方法:将大鼠C6胶质瘤细胞分为对照组、人参皂苷Rh2低剂量组(16 μg/mL)、人参皂苷Rh2中剂量组(32 μg/mL)、人参皂苷Rh2高剂量组(48 μg/mL),CCK-8法和平板克隆实验检测细胞增殖;流式细胞术检测细胞凋亡;Transwell检测细胞侵袭;实时荧光定量-聚合酶链式反应(qRT-PCR)检测C6胶质瘤细胞中VEGF、Siah-1、Synaptophysin、MMP-9 mRNA表达;蛋白质印迹法(Western blot)检测C6胶质瘤细胞中VEGF、Siah-1、Synaptophysin、MMP-9蛋白表达。结果:与对照组比较,人参皂苷Rh2低剂量组、人参皂苷Rh2中剂量组、人参皂苷Rh2高剂量组大鼠C6胶质瘤细胞OD450值(24 h、48 h)、克隆形成率、细胞侵袭数、VEGF、Synaptophysin、MMP-9 mRNA及蛋白表达降低,细胞凋亡率、Siah-1 mRNA及蛋白表达升高,且呈剂量依赖性(P<0.05)。结论:人参皂苷Rh2可能通过上调Siah-1,下调VEGF、Synaptophysin、MMP-9表达来抑制大鼠C6胶质瘤细胞增殖与侵袭,促进细胞凋亡。  相似文献   

10.
目的研究人脐带间充质干细胞(hUCMSCs)体外模型中对胶质瘤细胞株U87荷瘤能力及其上皮间质转化(EMT)的影响及其可能机制。方法建立裸鼠皮下荷瘤模型,观察hUCMSCs与U87共培养组和U87单独荷瘤组皮下荷瘤能力的差别,免疫组化检测EMT相关基因组织表达水平,Western Blot检测EMT相关蛋白MMP2,MMP7,MMP9,E-cadherin(E-cad),N-cadherin(N-cad)和Vimentin(VIM)表达情况,q PCR检测EMT相关基因(mmp2,mmp7,mmp9,E-cad,N-cad和vimentin)转录水平。Transwell和Matrigel分别检测hUCMSCs对U87转移能力的影响,两组间比较拟采用独立样本t检验,多组间比较采用单因素方差分析。结果皮下荷瘤结果提示hUCMSCs与U87共培养组皮下荷瘤率高于U87单独荷瘤组,且肿瘤体积较大,RT-PCR结果提示:共培养组和单独培养组相比,E-cad水平下调,N-cad和VIM上调,且基质金属蛋白酶家族MMP2,MMP7,MMP9也有不同程度上调。Western blot结果提示:在蛋白水平共培养组和单独培养组相比,E-cad水平下调2.1倍,N-cad和VIM上调1.0倍,MMP9上调0.9倍;E-cad,N-cad,VIM以及MMP2变化结果与RT-PCR结果一致。免疫组化结果进一步验证hUCMSCs能促进U87表达Ki67,E-cad与N-cad低表达。Transwell和Matrigel实验结果提示hUCMSCs能够促进U87细胞的转移侵袭能力。结论 hUCMSCs能通过促进U87高表达EMT相关基因和增殖相关基因Ki67,从而促进胶质瘤细胞株U87皮下肿瘤形成并发生上皮间质转化,提示hUCMSCs临床应用中应该充分考略受试者是否是潜在胶质瘤患者。  相似文献   

11.
通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

12.
Seed germination of an aurea mutant of tomato ( Lycopersicon esculentum Mill.) is promoted by continuous irradiation with red, far-red or long-wavelength far-red (758 nm) light as well as by cyclic irradiations (5 min red or 5 min far-red/25 min darkness). Far-red light applied immediately after each red does not change the germination behaviour. Seed germination of the isogenic wild-type, cv. UC-105, is promoted by continuous and cyclic red light while it is inhibited by continuous and cyclic far-red light and by continious 758 nm irradiation. Far-red irradiation reverses almost completely the promoting effect of red light. The promoting effect (in the aurea mutant) and the inhibitory effect (in the wild-type) of continuous far-red light do not show photon fluence rate dependency above 20 nmol m−2 s−1. It is concluded that phytochrome controls tomato seed germination throgh low energy responses in both the wild type and the au mutant. The promoting effect of continuous and cyclic far-red light in the au mutant can be attributed to a greater sensitivity to Pfr.  相似文献   

13.
The levels of endogenous phytohormones and respiratory rate in nine sorts of flowers such as Cymbidium faberi Rolfe, Nopalxochia ackermannii Kunth and others were investigated both at full bloom and senescence and meanwhile the effect of exogenous phytohormones on prolonging the blossoms and promoting ethylene production were tested. There is a high content of endogenous ethylene in all the long-lived flowere, about 3–16 folds higer than the short-lived ones. There is a high level of ABA at full blooming flowers of short-lived flowers, in which there is no or only some cytokinins in it, but the ratio of CTK (6BA+zeatin)/ABA is smaller(l.7). The endogenous ABA reached a much higher level at senescence in all nine sorts of flowers, so it is reasonable to consider that it is ABA which plays an important role of regulation in controlling flower's senescence. There is a much higher level of GA3 and zeatin in the long-lived flowers which is not demonstrated in the shortlived ones. The respiratory rate is one of the factors controtling the longevity of flowers, but it does not play a decided role. Application of 6BA and zeatin prolongs distinctly orchid’s longevity, however exogenous IAA through the promotive action on ethylene production, evidently extends the longevity of the flowers of the Nopalxochia ackermannii Kunth.  相似文献   

14.
15.
龙胆科药用植物化学成分的研究现状   总被引:16,自引:0,他引:16  
龙胆科植物在我国的分布范围很广,且多数为药用植物,其多数种属的药用植物,至今其化学成分尚未被系统研究。综述了目前龙胆科药用植物的化学成分的研究现状及一般提取方法,对近年来发现的环烯醚萜及裂环烯醚萜类化合物进行了总结,为本科药用植物的更深入研究提供了参考。  相似文献   

16.
A complex analysis of seasonal fluctuations of the mean group parameters of the system of regulation of lipid peroxidation has been performed in liver of Balb/c mice. Association of lipid characteristics and morphophysiological parameters is studied in the Balb/c mouse liver. An inter-connection is revealed between the liver index and the amount of lysoforms of phospholipids, the scale and character of the interconnection differing essentially depending on proportion of phos-phatidylcholine in mouse liver phospholipids.  相似文献   

17.
18.
真菌类遗传学分析的知识结构教学   总被引:5,自引:2,他引:3  
罗桂花 《遗传》2002,24(3):349-350
本文以认知结构理论为指导,讨论了真菌类遗传分析与高等动植物遗传分析的内在联系,认为利用这种内在联系进行教学可收到好的效果并说明了作者的具体教学过程。 Abstract:In the paper, the relationship between genetic analysis of Fungi and genetic analysis of high animal and plant was discussed.A good results were obtained when we adopted this method in the teaching.  相似文献   

19.
Seven strains of aerobic carbon monoxide-oxidizing bacteria (carboxydebacteria) when growing on CO as sole source of carbon and energy had doubling times which ranged from 12–42 h. The activity profiles obtained after discontinuous sucrose density gradient centrifugation indicated that the CO-oxidizing enzymes are soluble and the hydrogenases are membrane-bound in all strains examined. The CO-oxidizing enzymes of Pseudomonas carboxydohydrogena, Pseudomonas carboxydoflava, Comamonas compransoris, and the so far unidentified strains OM2, OM3, and OM4 had a molecular weight of 230,000; that of Achromobacter carboxydus amounted to 170,000. The molecular weights of the CO-oxidizing and H2-oxidizing enzymes turned out to be identical. The cell sonicates were shown to catalyze the oxidation of both CO and H2 with methylene blue, thionine, phenazine methosulfate, toluylene blue, dichlorophenolindophenol, cytochrome c or ferricyanide as electron acceptors. Methyl viologen, benzyl viologen, FAD+, FMN+, and NAD(P)+ were not reduced. The spectrum of electron acceptors was identical for all strains tested. Neither free formate, hydrogen nor oxygen gas were involved in the CO-oxidation reaction. Methylene blue was reduced by CO at a 1:1 molar ratio. The results indicate that CO-oxidation by carboxydobacteria is catalyzed by identical or similar enzymes and that the reaction obeys the equation CO+H2OCO2+2H++2e- as previously shown for Pseudomonas carboxydovorans.Dedicated to Otto Kandler remembering almost three decades of enjoyable cooperation  相似文献   

20.
Summary Embryogenic tissues of sugi (Cryptomeria japonica) were induced on a modified Campbell and Durzan (CD) medium containing 1 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and 600 mg l−1 glutamine, and subcultured in the medium of the same composition for over 1 yr. This resulted in a mixed culture of embryogenic and non-embryogenic cells. When embryogenic cells were isolated and cultured independently, their capacity to form embryogenic aggregates was lost. Thus, the non-embryogenic cells present within a mixed culture system were essential to the formation of embryogenic aggregates. When embryogenic tissues were isolated and cultured independently on a high glutamine-containing (2400 mg l−1) medium, dry weights and endogenous levels of glutamine increased, and the tissue could generate a large number of embryogenic aggregates. Amino acid analysis of embryogenic and non-embryogenic cells from the maintenance culture indicated a higher level of glutamine was present in the latter. The high endogenous level of glutamine in the non-embryogenic portion of mixed cell masses may be the supplier of glutamine for maintaining the embryogenic property of the tissues.  相似文献   

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