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简介：Itiswellrecognizedthatcelldeathplaysanimportantroleduringthematurationofthenervoussystemaswellasinmanyneurologicaldiseases.Apoptosishasbeenshowntobeimportantparticularyduringembryogenesisasameanstoeliminatingunwantedneurons.SeveredaxonshavealsobeenshowntodegenerateinanorganizedfashiontermedWalleriandegeneration.Excitotoxicdeathisanotherformofcelldeathinthenervoussystemwhichisinducedbyhighconcentrationsofneurotransmitterssuchasglutamate.Itisnotknownwhetherthesamemolecularmechanismsunderliethesedifferentformsofcelldeathinthenervoussystem.TheBax-/-Bak-/-doubleknock-outmouseprovidesanidealsystemtostudy

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简介：神经干细胞(NSC)不仅在胚胎的发展期间而且在所有哺乳动物的种类的成年大脑是在场的，包括人。在vivo的干细胞壁龛建筑学使成年NSC能连续地在整个生活在特定的大脑区域产生功能的神经原。成年神经发生过程服从于动态规定由各种各样生理，病理学并且药理学刺激。Multipotent成年NSC也看起来内在地塑料，对基因编程顺从在正常区别期间，并且到epigeneticreprograming在进pluripotency的de区别期间。增加的证据建议成年NSC显著地在生理、病理学的条件下面贡献专业化神经功能。充分理解成年NSC的生物学将提供关键卓见进病原学和主要大脑混乱的潜在的治疗学的干预。这里，我们在哺乳动物的中央神经系统的成年NSC上考察最近的进步，包括他们在癌症和再生药的身份，壁龛，功能，粘性，和新兴的角色上的话题。

简介：Inthelasttwoyears,wehaveseenaremarkableintensificationintheresponsetoAIDSinChina.AnumberoforganizationshavejoinedandcontributedtotheeffortsoftheChinesegovernmentinrespondingtheAIDSepidemicinChina.ThisarticlespecificallydescribestheroleoftheUnitedNationsinsupportingandstrengtheningthoseresponses.AchievementsoftheUnitedNations(UN)highlightedinthearticleinclude:strengthenedleadershipandpoliticalcommitmenttorespondtoAIDS;improvedHIV/AIDSsurveillanceandinformation;expandedpreventionefforts;improvedtreatment,careandsupporttopeoplelivingwithHIVandincreasedresourcesforAIDSprograms.Additionalrolesofe.,onenationalplanonAIDS;onenationalcoordinatingauthorityforAIDS;andonemonitoringandevaluationsystemforAIDS.Inaddition,theUNsystemisexpectedtostrengthenalignmentandharmonizationofactivitiesofallinternationalorganizationsandimprovedaccountabilityandoversight.RemainingchallengesidentifiedincludeincreasingawarenessofAIDSandreducingstigmaanddiscrimination;reducingvulnerabilityandriskbehaviouramongspecificgroups;providingimprovedtreatment,careandsupportforpeoplelivingwithHIV;promotingstrongerengagementbycivilsociety,and;addressingthegenderdimensionsofAIDS.

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简介：TheposteriorgutoftheDrosophilaembryo,consistingofhindgutandMalpighiantubules,providesasimple,well-definedsystemwhereitispossibletouseageneticapproachtodefinecomponentsessentialforepithelialmorphogenesis.WereviewheretheadvantagesofDrosophilaasamodelgeneticorganism,themorphogenesisoftheepithelialstructuresoftheposteriorgut,andwhatisknownaboutthegeneticrequirementstoformthesestructures.Inoverview,primordiaarepatternedbyexpressionofhierarchiesoftranscriptionfactors;thisleadstolocalizedexpressionofcellsignalingmolecules,andfinally,totheleastunderstoodstep:modulationofcelladhesionandcellshape.Wedescribeapproachestoidentifyadditionalgenesthatarerequiredformorphogenesisofthesesimpleepithelia,particularlythosethatmightplayastructuralrolebyaffectingcelladhesionandcellshape.

简介：叶绿体是从endosymbioticcyanobacteria演变的植物特定的细胞器。他们通过二进制分裂划分。叶绿体部门地点的选择为对称的叶绿体部门是枢轴的。在E。coli，在房间的中点部门地点放被Min系统的动态摆动调整，它包括MinC，头脑和矿。在植物的头脑和矿的相当或相同的事物涉及叶绿体分割。MinC的相当或相同的事物仍然没在更高的植物被识别。然而，象FtsZ一样蛋白质，ARC3，被发现地点放涉及叶绿体分割。这里，我们报导放1的那个叶绿体部门地点(AtCDP1)是在Arabidopsis涉及叶绿体部门地点放置的新奇叶绿体部门蛋白质。AtCDP1被与房间部门显型为殖民地在细菌屏蔽一个ArabidopsiscDNA表示图书馆发现。AtCDP1只在Arabidopsis在年轻绿纸巾被表示。有多重部门地点的伸长的叶绿体在loss-of-functioncdp1异种被观察。AtCDP1的Overexpression也引起了一个叶绿体部门显型。蛋白质相互作用试金建议AtCDP1可以调停通过和ARC3的相互作用放的叶绿体部门地点。总的来说，我们的结果显示AtCDP1是放系统，和这个系统的工作机制的叶绿体部门地点的一个新奇部件与在原核生物的房间的传统的MinCDE系统的不同。

简介：Afterpre-cultureandtreatmentofosmosis,cotyledonsofimmaturepeanut(ArachishypogaeaL.)zygoticembryosweretransformedviaparticlebombardmentwithaplasmidcontainingachimerichphgeneconferringresistancetohygromycinandachimericintron-gusgene.Selectionforhygromycinresistantcallusesandsomaticembryoswasinitiatedat10thdpost-bombardmentonmediumcontaining10-25mg/Lhygromycin.Undercontinuousselection,hygromycinresistantplantletswereregeneratedfromsomaticembryosandwererecoveredfromnearly1.6%ofthebombardedcotyledons.ThepresenceandintegrationofforeignDNAinregeneratedhygromycinresistantplantswasconfirmedbyPCR(polymerasechainreaction)fortheintron-gusgeneandbySouthernhybridizationofthehphgene.GUSenzymeactivitywasdetectedinleafletsfromtransgenicplantsbutnotfromcontrol,non-transformedplants.Theproductionoftransgenicplantsaremainlybasedonanewlyimprovedsomaticembryogenesisregenerationsystemdevelopedbyus.

简介：heterotrimericguanine核苷酸绑定蛋白质(G蛋白质)被表明了各种各样的发信号调停在植物的小径。然而，它在发信号的phytochromeA(phyA)的角色留下逃犯。在这研究，我们发现新调停phyA的显型指明了far-red照耀(FR)preconditioned房间死亡，它仅仅在跟随暴露到白光(WL)的FR-grown幼苗的胚轴发生。房间死亡在G变异的gpa1被减轻，但是与野类型(WT)比较在G变异的agb1加重了，在调停phyA的房间死亡小径的GPA1和AGB1的对抗角色的陈述语气。进一步的调查显示nonphotoconvertibleprotochlorophyllide(Pchlide633)的导致FR的累积，在暴露上产生反应的氧种类(ROS)到WL，为前提FR的房间死亡被要求。而且，ROS主要在叶绿体被检测用荧光灯探查。有趣地，到黑暗成年的幼苗的H2O2的申请导致类似于前提FR的房间死亡的显型。这表明ROS是为房间死亡的一个批评调停人。另外，我们观察到agb1比WT幼苗对H2O2更敏感，显示G蛋白质可以也修改到ROS应力的幼苗的敏感。一起拿这些结果，我们推断G蛋白质可以涉及表明小径调整Arabidopsis胚轴的前提FR的房间死亡的phyA。在phyA位于G蛋白质的参与下面发信号的可能的机制在这研究被讨论。

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简介：Thenon-classicalHLAclassIantigenHLA-GisanimmunemodulatorwhichinhibitsthefunctionsofTcells,NKcells,andtheDendriticcells(DC).Asaresult,HLA-Gexpressioninmalignantcellsmayprovidethemwithamechanismtoescapetheimmunesurveillance.Inmelanoma,HLA-Gantigenexpressionhasbeenfoundin30%ofsurgicallyremovedlesionsbutinlessthan1%ofestablishedcelllines.OnepossiblemechanismunderlyingthedifferentialHLAGexpressioninvivoandinvitroisthattheHLA-Ggeneisepigeneticallyrepressedinmelanomacellsinvitro.Totestthishypothesis,wetreatedtheHLA-GnegativemelanomacelllineOCM-1AwiththeDNAmethyltransferaseinhibitor5-aza-2'-deoxycytidine(5-AC)andanalyzedwhetherHLA-Gexpressioncanberestored.OurdatastronglysuggestthatHLA-GissilencedasaresultofCpGhypermethylationwithina5'regulatoryregionencompassing220bpupstreamofthestartcodon.Aftertreatment,HLA-GmRNAexpressionwasdramaticallyincreased.WesternblotandflowcytometryshowedthatHLA-Gproteinwasinduced.Interestingly,HLA-Gcellsurfaceexpressiononthe5-ACtreatedOCM-1AcellsismuchlessthanthatontheHLA-GpositiveJEG-3cellswhileasimilaramountoftotalHLA-Gwasobserved.Possiblemechanismsforthedifferencewereanalyzedinthestudysuchascellcold-treatment,peptideloadingandantigenprocessingmachinerycomponents(APM)aswellasβ2microglobulin(β2-m)expression.DatarevealedthattheAPMcomponentcalreticulinmightbeinvolvedinthelowerHLA-GsurfaceexpressiononOCM-1Acells.Takentogether,ourresultsindicatedthatDNAmethylationisanimportantepigeneticmechanismbywhichHLA-Gantigenexpressionismodulatedinmelanomacellsinvitro.Furthermore,tothefirsttime,wehypothesizedthatthedeficiencyofcalreticulinmightbeinvolvedinthelowHLA-Gsurfaceexpressiononthe5-ACtreatedOCM-lAcells.