简介：AninteractivetooltovisualizetheK-stringcompositionoflongDNAsequencesincludingbacterialcompletegenomesisdescribed.Itisespeciallyusefulforexploringshortpalindromicstructuresinthesequences.TheSeeDNAprogramrunsonRedHatLinuxwithGTK+support.Itdisplaystwo-dimensional(2D)orone-dimensional(1D)histogramsoftheK-stringdistributionofagivensequenceand/oritsrandomizedcounterpart.ItisalsocapableofshowingthedifferenceofK-stringdistributionsbetweentwosequences.TheCsourcecodeusingtheGTK+packageisfreelyavailable.

简介：应《中国真菌学杂志》主编温海教授的邀请，国际著名医学真菌学研究专家、隐球菌与隐球菌病研究领域的先驱和权威、美国国立卫生研究院（NIH）分子微生物学实验室主任K．J．Kwon-Chung教授于2006年6月2日来到上海，在上海长征医院就隐球菌病的基础和临床研究进行了专题学术交流。K．J．Kwon-Chung教授是国际知名的隐球菌研究专家，在Science，PNAS上均有多篇论文发表，发表SCI论文近200篇。

简介：Ionizingradiationisoneofthemosteffectivetoolsincancertherapy.Inapreviousstudy,wereportedthatproteintyrosinekinase(PTK)inhibitorsmodulatetheradiationresponsesinthehumanchronicmyelogenousleukemia(CML)celllineK562.Thereceptortyrosinekinaseinhibitor,genistein,delayedradiation-inducedcelldeath,whilenon-receptertyrosinekinaseinhibitor,herbimycinA(HMA)enhancesradiation-inducedapoptosis.Inthisstudy,wefocusedonthemodulationofradiation-inducedcelldeathbygenisteinandperformedPCR-selectsuppressionsubtractivehybridization(SSH)tounderstanditsmolecularmechanism.Weidentifiedhumanthymidinekinase1(TK1),whichiscellcycleregulatorygeneandconfirmedexpressionofTK1mRNAbyNorthernblotanalysis.ExpressionofTK1mRNAandTK1enzymaticactivitywereparallelintheirincreaseanddecrease.TK1isinvolvedinG1-Sphasetransitionofcellcycleprogression.Incellcycleanalysis,weshowedthatradiationinducedG2arrestinK562cellsbutitwasnotabletosustain.However,theadditionofgenisteintoirradiatedcellssustainedaprolongedG2arrestupto120h.Inaddition,theexpressionofcellcycle-relatedproteins,cyclinAandcyclinB1,providedtheevidencesofG1/SprogressionandG2-arrest,andtheirrelationshipwithTK1incellstreatedwithradiationandgenistein.TheseresultssuggestthattheactivationofTK1maybecriticaltomodulatetheradiation-inducedcelldeathandcellcycleprogressioninirradiatedK562cells.

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简介：<正>WeandothershavefirmlyestablishedthatsurfaceIgMreceptor(sIgM-R)crosslinkingwithantibodiestotheiheavychain(anti-i)leadstogrowtharrestandapoptosisinaseriesofwellcharacterizedB-celllymphomas.Thisrequiresablationofc-Mycproteinexpressionandtheconcomitantinductionofthecyclin-dependent-kinaseinhibitor,p27Kip1.Thesignalingmechanismsregulatingc-Mycandp27Kip1proteinexpressionarepoorlyunderstood.However,werecentlyestablishedthatsIgM-Rmediateddown-modulationofthePI-3Kpathwaydirectlyaffectedc-Mycandp27Kip1expressionandaccuratelypredictedgrowtharrest

简介：利用同源模建方法预测了t-PAK1区的三维结构。通过结构叠合确定了t-PAK1、K2区,纤溶酶原K1、K4区及UKK区的赖氨酸结合口袋。静电势计算及疏水性分析表明,在t-PAK2区以及纤溶酶原K1、K4区与纤维蛋白裸露的赖氨酸之间存在明显的静电势互补和疏水面契合。确定了影响Kringle区结合口袋与赖氨酸亲和的重要氨基酸,分析了t-PAK1区、UKK区不能结合赖氨酸的原因,由此设计了具有赖氨酸亲和力的新型t-PAK1区及UKK区突变体。利用模拟残基突变技术预测了突变体的结构变化,分析了突变后t-PAK1区及UKK区与赖氨酸亲和力的变化,初步在理论上肯定了设计方案的合理性。

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简介：OverexpressionandactivationofHER-2/neu(alsoknownasc-erbB-2),aproto-oncogene,wasfoundinabout30%ofhumanbreastcancers,promotingcancergrowthandmakingcancercellsresistanttochemo-andradio-therapy.Wild-typep53iscrucialinregulatingcellgrowthandapoptosisandisfoundtobemutatedordeletedin60-70%ofhumancancers.Andsomecancerswithawild-typep53donothavenormalp53function,suggestingthatitisimplicatedinacomplexprocessregulatedbymanyfactors.Inthepresentstudy,weshowedthattheoverexpressionofHER-2/neucoulddecreasetheamountofwild-typep53proteinviaactivatingPI3Kpathway,aswellasinducingMDM2nucleartranslocationinMCF7humanbreastcancercells.BlockageofPI3KpathwaywithitsspecificinhibitorLY294002causedG1-Sphasearrest,decreasedcellgrowthrateandincreasedchemo-andradio-therapeuticsensitivityinMCF7cellsexpressingwild-typep53.However,itdidnotincreasethesensitivitytoadriamycininMDA-MB-453breastcancercellscontainingmutantp53.OurstudyindicatesthatblockingPI3KpathwayactivationmediatedbyHER-2/neuoverexpressionmaybeusefulinthetreatmentofbreasttumorswithHER-2/neuoverexpressionandwild-typep53.