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91.
肿瘤-睾丸抗原基因在肾透明细胞癌中的表达 总被引:1,自引:1,他引:0
目的 研究6种肿瘤.睾丸抗原(CT)基因在肾透明细胞癌中的表达及其临床意义.方法 采用逆转录-聚合酶链反应(RT-PCR)技术检测42例肾透明细胞癌患者癌组织(新鲜标本,T1期16例,12期12例,T3期10例,T4期4例;G1 10例,G2 18例,G3 14例)及其中14例患者癌旁组织的cTAGE-1、cTAGE-2、MAGE-A1、MAGE-A3、MAGE-A12及NY-ESO-1基因mRNA的表达.结果 42例肾透明细胞癌组织中100%(42/42)至少表达6种CT基因中一种,14例癌旁组织表达均阴性.肾透明细胞癌组织中MAGE-A12表达最高,其次为MAGE-A3,MAGE-A1,cTAGE-1,cTAGE-2及NY-ESO-1,分别为71%(30/42),69%(29/42),67%(28/42),64%(27/42),60%(25/42)及48%(20/42).肿瘤不同分期、不同分级之间6种CT基因表达的差异均无统计学意义(Pearson x2检验法,P>0.05).结论 CT基因在肾透明细胞癌中有较高表达,可望成为肾透明细胞癌特异性免疫治疗的靶基因. 相似文献
92.
93.
目的构建+10Gz重复暴露大鼠脑差异表达基因的消减cDNA文库。方法本实验用SD大鼠,分别提取暴露组与对照组的总RNA,并分离纯化mRNA,应用抑制性消减杂交技术分离+10GI重复暴露大鼠脑差异表达基因eDNA片段并建立消减eDNA文库;利用PCR对随机挑选的75个白色菌落进行插入片段的验证,对其中70个克隆进行eDNA斑点杂交验证。结果所构建的eDNA文库扩增后包含约400个白色克隆和100个兰色克隆,随机挑选75个白色克隆入质粒载体后共获得70个阳性克隆。结论应用抑制性消减杂交技术成功构建了+10Gz重复暴露大鼠脑差异表达基因消减eDNA文库,为进一步筛选和克隆脑损伤相关基因奠定了基础。 相似文献
94.
Differential Cellular Gene Expression in Ganglioglioma 总被引:1,自引:0,他引:1
Uzma Samadani †Alexander R. Judkins ‡Albert Akpalu §Eleonora Aronica ¶Peter B. Crino 《Epilepsia》2007,48(1):646-653
Summary: Purpose: Gangliogliomas (GGs) are neuronal-glial tumors highly associated with epilepsy. We hypothesized that the expression of select gene families including neurotransmitter receptor subunits and growth factors would be distinct in neurons and astrocytes within GG compared with adjacent cortex and that these changes would yield insights into seizure onset and lesion formation.
Methods: Candidate gene expression was defined in single immunohistochemically labeled neurons and astrocytes microdissected from GG specimens compared with neurons and astrocytes microdissected from morphologically intact cortex adjacent to the GG or normal control cortex.
Results: Differential expression of 16 genes including glutamate transporter (EAAC1) and receptor (NMDA2C, mGluR5), growth factor (hepatocyte growth factor), and receptor (platelet derived growth factor receptor β, fibroblast growth factor receptor 3) mRNAs was detected in GG neurons compared with control neurons. In astrocytes, altered expression of p75NGF, mGluR3, TGFβ3 and Glt-1 mRNAs was detected. Nestin mRNA, a gene that exhibits enhanced expression in balloon cell cortical dysplasia, was increased in GG neurons. Because of the morphological similarities between GG and cortical dysplasia, we show that there is activation of the mTOR cascade in GG as evidenced by enhanced expression of phospho-p70S6kinase and phosphoribosomal S6 proteins.
Conclusion: We find differential candidate gene expression in neurons and astrocytes in GG compared with adjacent cortex and show that there is activation of the mTOR pathway. These changes highlight pathways that may be pivotal for epileptogenesis and lesion growth. 相似文献
Methods: Candidate gene expression was defined in single immunohistochemically labeled neurons and astrocytes microdissected from GG specimens compared with neurons and astrocytes microdissected from morphologically intact cortex adjacent to the GG or normal control cortex.
Results: Differential expression of 16 genes including glutamate transporter (EAAC1) and receptor (NMDA2C, mGluR5), growth factor (hepatocyte growth factor), and receptor (platelet derived growth factor receptor β, fibroblast growth factor receptor 3) mRNAs was detected in GG neurons compared with control neurons. In astrocytes, altered expression of p75NGF, mGluR3, TGFβ3 and Glt-1 mRNAs was detected. Nestin mRNA, a gene that exhibits enhanced expression in balloon cell cortical dysplasia, was increased in GG neurons. Because of the morphological similarities between GG and cortical dysplasia, we show that there is activation of the mTOR cascade in GG as evidenced by enhanced expression of phospho-p70S6kinase and phosphoribosomal S6 proteins.
Conclusion: We find differential candidate gene expression in neurons and astrocytes in GG compared with adjacent cortex and show that there is activation of the mTOR pathway. These changes highlight pathways that may be pivotal for epileptogenesis and lesion growth. 相似文献
95.
AMAL KANBOUR-SHAKIR DAVID T. ARMSTRONG ANNE ROULEAU HEINZ W. KUNZ THOMAS J. GILL 《American journal of reproductive immunology (New York, N.Y. : 1989)》1995,33(5):367-372
PROBLEM : To determine whether seminal fluid influences the expression of MHC class I antigens on the surface of basal trophoblast cells in the placenta of the rat. METHODS : Transfer of DA × DA embryos into a WF (allogeneic) or DA (syngeneic) recipient made pseudopregnant by hormonal treatment followed by mating with a vasectomized male (seminal fluid) or by mechanical stimulation (no seminal fluid). Antigen expression was determined by electron microscopic immunocytochemistry using the appropriate gold-labeled monoclonal antibodies. RESULTS : Seminal fluid did not affect the expression of MHC class I antigens on the surface of the basal trophoblast in either allogeneic or syngeneic matings. CONCLUSIONS : The suppression of the expression of paternal class I antigens on the surface of the basal trophoblast cells in allogeneic pregnancies most likely occurs at the genome level shortly after fertilization. 相似文献
96.
人碱性成纤维细胞生长因子基因在大肠杆菌中的克隆与表达 总被引:1,自引:0,他引:1
应用DNA重组技术将编码人碱性成纤维细胞生长因子(bbFGF)的基因克隆至原核高效表达质粒pBV_(221)的启动子下游。SDS-SAGE、ELISA和NTT活性监测结果表明:该重组质粒pBV-hbFGF在大肠杆菌DH5α中,经42℃诱导后,可表达出有较高生物活性的hbFGF。 相似文献
97.
Variation of prostate-specific antigen expression in different tumour growth patterns present in prostatectomy specimens 总被引:3,自引:0,他引:3
M. P. W. Gallee E. Visser-de Jong J. A. G. M. van der Korput Th. H. van der Kwast F. J. W. ten Kate F. H. Schroeder J. Trapman 《Urological research》1990,18(3):181-187
Summary A series of 55 randomly chosen radical prostatectomy specimens was analyzed for expression of prostate-specific antigen (PSA) by immunohistochemical techniques. Tissue sections were selected in such a manner that in addition to glandular benign prostatic hyperplasia (BPH), one or more different prostatic tumour growth patterns were present. Four monoclonal antibodies, directed against three different PSA epitopes, and one polyclonal anti-PSA antiserum were used. Expression of PSA was compared with that of prostate-specific acid phosphatase (PAP), recognized by two different polyclonal antisera. A critical dilution aimed at a maximum of staining intensity on BPH tissue sections was chosen for all antibodies. Anti-PSA and anti-PAP antisera stained essentially all BPH samples (over 90%). Irrespective of the nature of the antibodies used, PSA expression was found to be decreased in prostatic carcinoma. A clear cut relationship was found between immunoreactivity for PSA and the degree of differentiation of the tumour area. Under the experimental conditions used the PSA monoclonal antibodies stained only 1 out of 10 undifferentiated carcinomas, whereas 50% to 70% of the well- and moderately-differentiated carcinomas showed immunoreactivity. This correlation was less pronounced with the PAP staining pattern. If the PSA antibody titer was raised the percentage of clearly staining undifferentiated carcinomas could be considerably increased (up to 60%–100%), indicating that PSA expression is not absent, but lowered in most (if not all) undifferentiated carcinomas. 相似文献
98.
Masami Yoshida Hideyasu Yokoo Kimihiro Nakahara Masaru Tomita Naoyuki Hamada Michiko Ishikawa Jyunko Hatakeyama Masatoshi Tanaka Ikuko Nagatsu 《Brain research》1997,767(2):87
Infusion of muscimol (5×10−5 M, 60 min) into the nucleus accumbens (NAC) through a dialysis membrane caused a significant increase in extracellular dopamine (DA) and its metabolite, 3,4-dihydroxyphenylacetic acid (DOPAC). Fos-like immunoreactivity induced by intra-NAC infusion of muscimol was seen ipsilaterally in many accumbofugal target areas, but no Fos-positive neurons were seen in the vicinity of the dialysis membrane in the NAC. Sequential staining of Fos and tyrosine hydroxylase (TH) immunoreactivities revealed that a portion of A10 dopaminergic neurons were double-labelled. These results suggest that muscimol in the NAC disinhibits mesolimbic DA neuronal activity possibly through activity of the accumbofugal GABA neuron system. 相似文献
99.
FIONA TOMLEY 《Parasite immunology》1994,16(8):407-413
Total polypeptides from unsporulated and sporulated oocysts, sporozoites and the first two generations of merozoites of Eimeria tenella were fractionated by electrophoresis through polyacrylamide gels. The parasites are complex and the arrays of polypeptides differ for each of the developmental stages indicating that there is stagespecific control of gene expression. In particular, first generation merozoites display a markedly different polypeptide profile to that of either sporozoites or second generation merozoites. Changes in antigenicity during sporulation and the antigenic relationships between the three asexual zoite stages were examined by probing electroblotted polypeptides with a panel of antisera raised in rabbits to purified preparations of each stage. Antigenic cross-reactivity is well maintained throughout sporulation even though the sizes of antibody-reactive polypeptides change. In contrast there is a marked lack of cross-reactive epitopes between sporozoites, first and second generation merozoites. 相似文献
100.
钩体基因疫苗对豚鼠延髓原癌基因表达的影响 总被引:1,自引:1,他引:0
我们的研究已表明,赖型017株钩体外膜疏水蛋白OmpL39是稳定的免疫原,在此我们分别用OmpL39与钩体死菌苗和生理盐水对照免疫豚鼠,研究OmpL39的免疫保护作用和免疫机理,对OmpL39的抗原特异性刺激引起中枢原癌基因(Cfos基因)表达进行了观察。结果表明,OmpL39在豚鼠体内能产生高效价的阳性抗体,免疫保护率为100%。在OmpL39对中枢Cfos基因表达的影响中,我们观察到OmpL39免疫的豚鼠较空白和死菌苗组Cfos表达明显少于死菌苗组和空白对照组(p<005)。提示OmpL39能特异性地抑制Cfos基因的表达,减轻强毒钩体对动物体内的病理损伤,有较死菌苗强的免疫保护作用。 相似文献