简介:目的探讨原发性肝细胞癌RNA,DNA定量测定的临床意义。方法应用流式细胞分析技术。对64例原发性肝细胞癌(PHC)RNA,DNA含量进行定量分析。并对病人进行1-5.5年的随访。结果RNA指标和DNA指标对PHC的临床病理诊断符合率分别为93.7%和75.0%,RNA指标更敏感,双指标联合应用与临床病理诊断符合率为96.8%;DNA倍体与年龄,HCV感染密切相关(P<0.05)。与性别,AFP水平,HBsAg及瘤体大小无关;DI随组织学分级的增高而增加(P<0.05)。RNA和DNA含量与预后密切相关(P<0.01-0.05)。结论RNA,DNA含量可作为PHC诊断及判断预后的理想指标,RNA及DNA双指标同时应用优于任一单项指标。
简介:Heterogeneousnuclearribonucleoproteins(hnRNPs)arespliceosomalmacromolecularassemblagesandthusactivelyparticipateinpre-mRNAmetabolism.Theyarecomposedofevolutionarilyconservedandtandemlyrepeatedmotifs,wherebothRNA-bindingandprotein-proteinrecognitionoccurtoachievecellularactivities.Byyetunknownmechanisms,theseribonucleoprotein(RNP)particlesaretargetedbyautoantibodiesandhenceplaysignificantroleinavarietyofhumansystemicautoimmunediseases.Thisfeaturemakesthemimportantprognosticmarkersintermsofmolecularepidemiologyandpathogenesisofautoimmunity.SinceRNPdomainisoneofthemostconservedandwidespreadscaffolds,evolutionalysesoftheseRNA-bindingdomainscanprovidefurthercluesondisease-specificepitopeformation.ThestudypresentedhereinrepresentsasequencecomparisonofRNA-recognitionregionsofrecentlyclonedandcharacterizedhumanhnRNPA3withthoseofotherrelevanthnRNPA/B-typeproteins.Theirimplicationsinhumanautoimmunityareparticularlyemphasized.
简介:作为一个模式植物,烟草在植物分子生物学研究中发挥着重要的作用。总RNA的提取质量,对于基因表达、基因克隆、cDNA文库建立、RNA原位杂交以及转基因材料鉴定等分子生物学基础研究至关重要。尤其在进行基因克隆及cDNA文库时,只有高质量的RNA,才能保证cDNA第一链合成的完整性。由于烟草中糖类、蛋白质及次生代谢物的含量较高,因此,在应用TRIzolRNA提取试剂盒进行烟草总RNA提取时,所提取的RNA产物中的蛋白质及多糖等杂质含量偏高。因此,针对这一问题,我们对TRIzol法进行了改进,并获得了高质量的烟草总RNA。经琼脂糖电泳检测,利用该方法提取的烟草总RNA,条带清晰、无拖尾现象,28S与18S的比例约为2:1。紫外吸收值的测定表明,所提取的烟草总RNA的A260/A280的值基本达到了1.9以上,说明所提取的RNA的质量较高,可广泛应用于基因的克隆及基因的表达研究。
简介:Anincreasingnumberofstructuralhomologysearchtools,mostlybasedonprofilestochasticcontext-freegrammars(SCFGs)havebeenrecentlydevelopedforthenon-codingRNAgeneidentification.SCFGscanincludestatisticalbiasesthatoftenoccurinRNAsequences,necessarytoprofilespecificRNAstructuresforstructuralhomologysearch.Inthispaper,asuccinctstochasticgrammarmodelisintroducedforRNAthathascompetitivesearcheffectiveness.Moreimportantly,theprofilingmodelcanbeeasilyextendedtoincludepseudoknots,structuresthatarebeyondthecapabilityofprofileSCFGs.Inaddition,themodelallowsheuristicstobeexploited,resultinginasignificantspeed-upfortheCYKalgorithm-basedsearch.
简介:Objective:TostudytheeffectofantisenseVEGFRNAonratC6gliomasinvivoandfindoutthefeasibilityofantiangiogenesistherapywithantisenseVEGFRNAformalignantgliomas.Methods:ParentalratC6gliomacellsandC6cellstransfectedwithantisenseVEGFcDNAwereimplantedintracerebrallyandsubcutaneouslyintoSDratsascontrolandtransfectedgroup.RatsbearingcerebralandsubcutaneousC6gliomasweretreatedwithantisenseVEGFcDNAastreatedgroupandsenseVEGFcDNAandemptyvectorascontroloftreatedgroup.Thegeneralmanifestation,survivaltime,MRIandhistopathologicalchangesofallratswereobserved.Thevolumeofsubcutaneouslyimplantedtumorswasdeterminedregularly.InsituhybridizationandimmunohistochemicalstainingwereusedfordetectionofVEGFgeneexpressionofgliomaswhilePCNAimmunostainingandTUNELmethodforexaminationofproliferationactivityandapoptosisofgliomas,respectively.Results:Thesurvivaloftheratsintransfectedandtreatedgroupwasprolonged.Thereweretworatssurvivingover90dinthetreatedgroupandtheirtumorsdisappeared.TheVEGFgeneexpression,thenumberofmicrovesselsandtheproliferationactivityweredecreasedandalargeamountofapoptoticcellscouldbefoundincerebralandsubcutaneousgliomasintreatedandtransfectedgroups.Conclusion:VEGFisoneofthecandidategenesforgenetherapyofmalignantgliomas.AntisenseVEGFRNAcombinedwithothertherapiesshouldbestudiedfurtherforenhancingthetherapeuticeffectofmalignantgliomas.
简介:目的构建表达Nogo受体(NgR)特异性siRNA199的重组质粒。方法按照E1bashir等设计原则和siRNA表达载体的要求,在合成、筛选出基因沉默效率较高的siRNA199基础上,设计带有BamHⅠ、HindⅢ酶切黏性末端、终止识别序列和LOOP环的shRNA,并将其克隆入载体pRNAT-1/6.1/Neo,构建成NgR特异siRNA199重组质粒,然后进行酶切鉴定及基因测序。结果设计的shRNA成功克隆入载体pRNAT-1/6.1/Neo,构建成NgR特异siRNA199重组质粒,酶切鉴定及基因测序表明设计序列完全相符,目的基因序列准确无误。结论重组质粒构建成功,为构建病毒载体及观察重组质粒抑制大鼠NgR基因的表达对脊髓损伤的修复作用奠定了基础。
简介:Inordertostudythefunctionalstructureofthetranscriptionterminatorsandthemechanismoftemination,asurveyofthechromatinstructure,includingthelocationofDNaseIhypersensitivesitesandthenucleosomearrangement,ofyeastADH1andFLPterminatorswasmade.TheresultsshowthatthereisnorelationshipbetweenthefunctionoftheterminatorsandtheexistenceofDNaseIhypersensitivesites.However,itisfoundthatthereisalwaysanucleosmoeattheimmediateupstreamofthetranscriptionalterminationsites.Asacontrol,thechromatinstructuresofthepBR322DNAfragmentsontheyeastshuttervectorsarealsoinvestigatedatthesametime.TherandomnucleosomearrangementonthebacterialDNAinyesastagreeswiththepublishedreports.Anewhypothesis,aboutthemechanismoftranscriptionalterminationisputforwardandthereasonofdifferentnucleosomearrengementontheDNAswhichareoriginallyfromdifferentspeciesinyeastisdiscussed.