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86 个结果
  • 简介:ObjectiveAdipose-derivedstemcells(ADSCs)aresuggestedtopossessahighlyplasticabilitytodifferentiateintoseveralspecificcelltypesinadditiontoadipocytelineages,includinggermlayertissue-specificcelllineagessuchaschondrocyte,myocyte,neuronal,andosteoblastlineages.TheaimofthisstudyistoestablishaninvitroculturetechniqueforADSCsinanadultguineapigmodelthatfacilitatetheirdifferentiationintohaircell-likecells.MaterialsandMethodsCellsfrominguinalfatpadsinadultguineapigswereculturedwithβ-mercaptoethanol,RA,Forskorin,Heregulin,bFGF,BDNFandEGF.Cellulardifferentiationwasexaminedusingimmunocytochemistrytechniques.ResultsTheADSCsdemonstratedhaircellimmunophenotypeswithexpressionofepitopesofthehaircellmarkerproteinmyosinⅦa.ConclusionADSCsfromadultguineapigadiposetissuecandifferentiateintohaircell-likecellswhenculturedinvitro.ADSCsmayserveasseedcellsfortissueengineering.

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  • 简介:Apoptosis,orcontrolledcelldeath,isanormalpartofcellularlifespan.Celldeathofcochlearhaircellscausesdeafness;anapoptoticprocessthatisnotwellunderstood.Worldwide,1.3billionhumanssuffersomeformofhearingloss,while360millionsufferdebilitatinghearinglossasadirectresultoftheabsenceofthesecochlearhaircells(WorldwideHearing,2014).Muchisknownaboutapoptosisinothersystemsandinothercelltypesthankstostudiesdonesincethemid-20thcentury.Herewereviewcurrentliteratureonapoptosisingeneral,andcausesofdeafnessandcochlearhaircellslossasaresultofapoptosis.ThefamilyofB-celllymphoma(Bcl)proteinsareamongthemoststudiedandcharacterized.WewillreviewcurrentliteratureontheBcl2andBcl6proteininteractionsinrelationtoapoptosisandtheirpossiblerolesinvulnerabilityandsurvivalofcochlearhaircells.

  • 标签: APOPTOSIS HAIR CELL BCL2 BCL6
  • 简介:Haircellsinthemammalianinnerearareveryfragileandareofteninjuredasaresultofacoustictraumaorexposuretoototoxicdrugs(cisplatin,aminoglycosides,etc)[1].Inamphibiansandbirds,spontaneous

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  • 简介:ObjectivesToevaluateperipheralauditorydysfunctioninseniledementiaofAlzheimer'sdisease(AD)anditsrelationshipwithcognitivedysfunction.MethodsPuretonethresholds,wordrecognitionscores(WRS),acousticimmittanceandauditorybrain-stemresponses(ABR)weretestedtoevaluatetheauditoryfunctionin43ADpatientsand50normalsubjects.ThetestreliabilityinthesesubjectswasexaminedbeforethetestresultswereevaluatedfortheircorrelationwiththeMiniMentalStateExamination(MMSE)score.ResultsTherewerenostatisticallysignificantdifferencesinperipheralauditoryfunctionsbetweenthetwoearsinthetestedsubjectsorbetweenthetwogroupswhentheauditometricresultsoftherightearwerecompared(P>0.05).Also,therewerenostatisticallysignificantdifferencesbetweenthetwogroupswhenaudiometrictestreliability,acousticimpedanceandABRresultswerecompared(P>0.05).ConclutionsThepuretoneaudiometricthresholdandWRSinADpatientsaresimilartothoseincomparablenon-ADsenilesubjects.Peripheralauditorydysfunctionisnotrelatedtocognitivedysfunction.

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  • 简介:Formanyyears,studiesaboutthecochleahavebeenmainlyfocusedonsensorycells,i.e.theinnerhaircell(IHC)andouterhaircell(OHC),andtheneuronsystem.Supportingcells,suchasHensen'scellsandDeiters'cellsarelessstudied.Theirphysiologicalfunctionsandothercharacteristicsarenotwelldocumented.Nowadays,supportingcellsareanewworldattractingtoscientists'interests.Thescopeofthisreviewistodetailthebiologicalpropertiesofthesupportingcells,mainlyHensen'scellsandDeiters'cellsinthecochlea.Studiesonthissubjectwillbehelpfulinunderstandingphysiologyofthecochlea,andhopefullyprovidenewapproachesintreatingdiseasesofinnerear.

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  • 简介:Cochlearouterhaircells(OHCs)areinvolvedinamechanicalfeedbackloopinwhichthefastsomaticmotilityofOHCsisrequiredforcochlearamplification.Alternatively,amplificationisthoughttoarisefromactivehairbundlemovementsobservedinnon-mammalianhaircells.Wemeasuredthevoltage-evokedhairbundlemotionsinthegerbilcochleatodetermineifsuchmovementsarealsopresentinmammalianOHCs.TheOHCsdisplayedalargehairbundlemovementthatwasnotbasedonmechanotransducerchannelsbutbasedonsomaticmotility.Significantly,bundlemovementswereabletogenerateradialmotionofthetectorialmembraneinsitu.Thisresultimpliesthatthemotility-associatedhairbundlemotionmaybepartofthecochlearamplifier.

  • 标签: 径向运动 外毛细胞 放大器 耳蜗 哺乳动物 机械反馈
  • 简介:Apicalmembranerecyclinghasbeenproposedtobeimportantfornormalhaircellfunction.Thecurrentstudyreportsaninvitroworkthatdemonstratesthepresenceofphosphatidylserine(PS)andPS-positivevesicleslabeledbyAnnexinVintheapicalportionofhaircells.ThefollowingcharacteristicsofthePS-positivevesicleswerenoticedusingscanningconfocalfluorescencemicroscopy:(1)variablesizesaround200nm;(2)variabledistributionpatterns(eitheruniformlyalongindividualstereociliainthehairbundleorirregular)inthestereociliafromcelltocell;(3)variablesizesandnumbersatlocationsalongtheborderofthecuticularplate(CP),withalargenumberofthemlocatedatthevestigalkinociliallocation;(4)motilitywithsomeofthevesiclesduringtheobservationperiod;(5)increaseinPSlabelingandthenumberofPS-positivevesiclesafterloudsoundstimulation;and(6)decreasedPSlabelingandPS-positivevesiclenumbersfollowingtreatmentwithLY-294002,aPI3-kinaseinhibitor.TheseresultssuggestthatthepresenceofPS-positivevesiclesattheapicalareaofhaircellsmaybeindicativeofvesiclesheddingortransportationofaproteinorrafts.

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  • 简介:Ashybridcochlearimplantdevicesareincreasinglyusedforrestoringhearinginpatientswithresidualhearing,itisimportanttounderstandelectricallyevokedresponsesincochleaehavingfunctionalhaircells.Totestthehypothesisthatextracochlearelectricalstimulation(EES)fromsinusoidalcurrentcanprovokeanauditorynerveresponsewithnormalfrequencyselectivity,theEES-evokedcompoundactionpotential(ECAP)wasinvestigatedinthisstudy.Briefsinusoidalelectricalcurrents,deliveredviaaroundwindowelectrode,wereusedtoevokeECAP.TheECAPwaveformwasobservedtobethesameastheacousticallyevokedCAP(ACAP),exceptforashorterlatency.Theinput/outputandintensity/latencyfunctionsofACAPsandECAPswerealsosimilar.ThemaximumacousticmaskingforbothACAPandECAPoccurrednearprobefrequencies.SincethemaskedtuningcurveofaCAPreflectsthefrequencyselectivityofneuralexcitation,thesedatademonstrateahighlyspecificactivationoftheauditorynerve,whichwouldresultinhighdegreeoffrequencyselectivity.Thisfrequencyselectivitylikelyresultsfromthecochleartravelingwavecausedbyelectricallystimulatedouterhaircells.

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  • 简介:ObjectivesToestablishamethodforhighyieldmesenchymalstemcellscollection,aswellasaculturemethodforidentifyingmesenchymalstemcellsfromtheswineadipose-derivedmesenchymalstemcell(ADMSC).MethodsSwineADMSCswereisolatedfromfattissuewithcollagenase,followedbyinductionofdifferentiationtoosteogenic,adipogenicandchondrogrniccells.ThesurvivalcurveoftheADMSCatthe37oCand38oCweremeasuredusingWST-1CellProliferationAssayReagent.ResultADMSCsisolatedwithcollagenasefromswineneckfattissuegeneratedastableuniformappearanceafterthesecondgeneration.Thepassageperiodwasfivedays.ADMSCcoulddifferentiateintoosteogenic,adipogenicorchondrogrniccellsunderdifferentcultureconditions.Thehighestgrowthratewasachievedat38oCinthisstudy.ConclusionSwineADMSCshavethepotentialtodifferentiateintoosteogenic,adipogenicorchondrogrniccells,andtheymaybeappropriatefortransplantationforbothresearchandclinicalpurpose.

  • 标签: 间充质干细胞 脂肪来源 分化诱导 围网 脂肪组织 细胞分离
  • 简介:Hearingloss(HL)isoneofthemostwidespreadsensorydisorders,affectingapproximately1in500newborns.HeritablediseasesoftheinnereararetheleadingcausesofprelingualHL.TreatingofhereditaryHLandunderstandingitsunderlyingmechanismsremaindifficultchallengestootolaryngologists.Asstemcellsarecapableofself-renewalanddifferentiation,theyareideallysuitedbothfordiseasemodelingandregenerativemedicine.Recently,descriptionofinducedpluripotentstemcells(iPSCs)hasallowedthefieldofdiseasemodelingandpersonalizedtherapytobecomefarmoreaccessibleandphysiologicallyrelevant,asiPSCscanbegeneratedfrompatientsofanygeneticbackground.ThisreviewbrieflydescribestheadvantagesofiPSCstechnologyanddiscussespotentialapplicationsofthispowerfulbiologicaltoolinstudyingandtreatinghereditaryHL.

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  • 简介:ObjectiveToestablishalymphocytelinecapableoflongsurvivalandexpressinghumanNT-3tolayafoundationforfutureanimalandhumancochleargenetransfectionresearch.MethodsWecollectedlymphocytesfromnormalhumanbloodviaFicollfluidandaddedIL-2intotheserumculturemediumtopromotelymphocytegrowth.TheNT3cDNAwasobtainedbyRT-PCRandligatedwiththeeukaryonvectorwhichispIRES-DsRed2usingT4DNAenzyme.TheNT3cDNAgenewastransfectedintothelymphocytelineusingcationicliposome(LP2000).ThelymphocytestransfectedwithNT3-cDNAwereexaminedbyRT-PCRandWestern-blotmethods.ResultsWeestablishedanewmethodtoextendinvitrolymphocytessurvivaltimeandtotransfectNT3intolymphocytes.Thegeneticallyengineeredlymphocyteswerecapableofsurvivingoverrelativelylongtime.PositiveproteinsignalswereobtainedbyWesternblot.ConclusionsUsinglymphocytesastheintermediary,recombinedplasmidpIRES-DsRed2NT3isusedtoestablishalymphocytelinethatexpressesandsecretesNT3.Thiscelllinecanbeusedinfutureanimalgenecochleartransfectionresearchandmayhelpfindanintermediarycelllineforgenetherapyforhumandeafness.

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  • 简介:ObjectiveTheaimofthisstudyistoinvestigatetheeffectoftransfectedhTERTgeneoncellapoptosisofnewbornratcochlearbasilarmembranecells(CBMCs).MethodsCBMCsisolatedfromnewbornratcochlearweretransfectedusingaplasmidcontaininghumantelomerasereverasetranscriptasegene(pCI-neo-hTERT),andwerescreenedusingG418toobtainstabletransfectedcelllines.Cellapoptosisratewasanalyzedbyflowcytometry.hTERTandapoptosisrelatedgenesexpressionweredetectedbyreversetranscriptasepolymerasechainreaction(RT-PCR).ResultshTERTgeneexpressionwasdetected72hoursaftergenetransfectionintransfectedcells.TheapoptoticrateoftransfectedCBMCssignificantlyreduced.Expressionofapoptosisrelatedgenescorrespondinglychanged.ConclusionTransfectionofhTERTgeneleadstoreducedapoptosisrateinnewbornratCBMCs.andlowerexpressionofapaf1,Caspase3andBCL2intransfectedcellsascomparedtothatofnormalCBMCs.

  • 标签: COCHLEAR BASILAR membrane cel(lCBMC) HTERT rat
  • 简介:ObjectiveThisstudyistoexploretherelationshipbetweenacetylcholine(ACh)-inducedcalciumreleasefromintracellularCa2+storesandfunctionofouterhaircell(OHC)motors,inanattempttoelucidatethemechanismofOHCelectromotilityatrestingstate.MethodsOHCswereisolatedfromadultguineapig(200-300g)cochleaandloadedwithFluo-3/AM.ThecellsweretreatedwithACh/dHBSS,ACh/HBSS,dHBSSonlyorHBSSonly.Intracellular[Ca2+]ivariationsincellsunderthefourtreatmentswereobservedusinganAr-Krlaserscanconfocalmicroscope.Results[Ca2+]ioscillationswererecordedinfiveOHCstreatedwithACh/dHBSSbutnotinothercells.ThisisthefirsttimethatAch-excited[Ca2+]ioscillationsarereportedinguineapigOHCsindependentofextracellularcalcium.ConclusionsACh-excited[Ca2+]ioscillationsinOHCsoriginatesfromintracellularcalciumreleaseandmayplayacrucialroleinmaintainingactivemechanicalmotilityoftheOHCatrestingandmodulatingOHCelectromotility.

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  • 简介:ObjectiveTostudygentamicininjurymechanismsusingpostnatalmousecochlearspiralgangcells(SGC).MethodsSGCswereisolatedusingacombinatorialapproachofenzymaticdigestionandmechanicalseparationfromP2~6Kunmingmousecochleae.After4days,culturedSGCswerefixedwith4%paraformaldehydeatroomtemperatureforimmunocytochemicalexaminationusingthemethodsofS-Pandthemonoclonalantibodyagainstmouseneurofilamentprotein(Neurofilament-68/200Kda,NF-L+H).SGCswererandomlydividedintoablankcontrolgroupandthreegentamicintreatmentgroups(mediumgentamicinconcentrationat50mg/L,100mg/Land150mg/Lrespectively),SGCswerecollectedandexaminedunderatransmissionelectronmicroscopeafterbeingculturedfor48h.ResultsSGCprimaryculturewassuccessful.SGCcytoplasmandneuritesweredyedbrownishyellowbythemonoclonalmouseneurofilamentproteinantibody.SGCsshowedclassicalbipolarneuronappearance.Underthetransmissionelectronmicroscope,.gentamicintreatedSGCsshowedmorphologicalfeaturesdifferentcomparedtothoseintheblankcontrolgroup,whichmightindicateapoptosis.ConclusionOurresultsindicatethatgentamicinhasdirecttoxiceffectsoncochlearSGCsinmiceandtheinjurymechanismiscloselyrelatedwithapoptosis.Damagetomitochondriamayplayanimportantroleintheprocess.

  • 标签: 庆大霉素 昆明小鼠 损伤机制 神经节细胞 耳蜗 培养
  • 简介:Microphthalmia-associatedtranscriptionfactor(MITF)controlsmelanocytesurvivalanddifferentiationthroughdirectlyregulatingtheexpressionofthetyrosinase(TYR)andtyrosinase-relatedproteins1and2(TYRP1andTYRP2)genes.MITFmutationshavebeenreportedtoresultinanabnormalmelanocytedevel-opmentandleadtoWaardenburgsyndrometype2(WS2),characterizedbyvariabledegreesofsensorineu-ralhearinglossandpatchyregionaldistributionofhypopigmentation.Recently,MITFwasalsoindicatedasacausativegeneforamoreseveresyndrome,theTietzSyndrome(TS),characterizedbygeneralizedhy-popigmentationandcompletehearingloss.However,fewfunctionalstudieshavebeenperformedtocom-parethediseases-causingmutations.Here,weanalyzedtheinvitroactivityoftworecentidentifiedWS2-as-sociatedmutation(p.R217Iandp.T192fsX18)andoneTS-associatedmutationp.N210K.TheR217IMITFretainedpartialactivity,normalDNA-bindingabilityandnucleardistribution,whereastheT192fsX18MITFfailedtoactivateTYRpromoterduetolossofDNA-bindingactivity,andaberrantsubcellularlocalization.TheaberrantsubcellularlocalizationofT192fsX18MITFmaybecausedbydeletionofaputativenuclearlocalizationsignal(NLS)ataa213-218(ERRRRF).Indeed,MITFwithdeletionoftheNLSfragmentfailedtotranslocateintothenucleusandactivatedtheTYRpromoter.TaggingthisNLStoGFPpromotedthegreenfluorescenceprotein(GFP)translocatedintothenucleus.ThesurprisingfindingofourstudyisthataTS-as-sociatedMITFmutation,N210K,showedcomparableinvitroactivityasWT.Thus,thepossibleinvolve-mentofMITFinTSanditsunderlyingmechanismsstillneedfurtherinvestigation.

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  • 简介:Thepurposeofthepresentstudywastodetermineprotectivieeffectsofbasicfibroblastgrowthfactor(bFGF)oncochlearneuronsandhaircellsinvitroandinvivo.InexperimentI,culturedspiralganglionneurons(SGNs)preparedfromP3micewereexposedto20mMglutamatefor2hoursbeforetheculturemediumwasreplacedwithfreshmediumcontaining0,25,50,and100ng/mlbFGF,respectively.Fourteendayslater,allcultureswerefixedwith4%paraformaldehyde,andstainedwith1%toluidineblue.ThenumberofsurvivingSGNswerecountedandthelengthofSGNsneuritesweremeasured.Exposureto20mMglutamatefor24hoursresultedinaninhibitiononneuriteoutgrowthofSGNsandelevatedcelldeath.TreatmentofthecultureswithbFGFledtopromotionofneuriteoutgrowthandelevatednumberofsurvivingSGNs.EffectsofbFGFweredosedependentwiththehighestpotencyat100ng/ml.InexperimentⅡ,invivostudieswerecarriedoutwithguineapigsinwhichbFGForartificialperilymphwasperfusedintothecochleatoassesspossibleprotectiveeffectsofbFGFoncochlearhaircellsandcompoundactionpotentials(CAP).TheCAPsweremeasuredbefore,immediatlyand48hoursafterexposuretonoise.SignificantdifferencesinCAPwereobserved(p<0.05)amongthebFGFperfusedgroup,controlgroup(t=3.896)andartificialperilymphperfusedgroup(t=2.520)at48hoursafternoiseexposure,CochleaewereremovedandhaircellLosswasanalyzedinsurfacepreparationspreparedfromallexperimentalanimals.Acoustictraumacausedlossof651and687innerhaircellsinthecontrolandartificialperilymphperfusedgroup,respectively.Insharpcontrast,only31innerhaircellswerelostinthebFGFperfusedears.Similarly,moreouterhaircellsdiedinthecontrolandperilymphperfuesedgroup(41830and41968,respectively)thaninthegrouptreatedwithbFGF(34258).OurresultsdemonstratethatbFGFprotectedSGNsagainstglutmateneurotoxicityinvitro.Inaddition,treatmentwithbFGFalso

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  • 简介:ObjectiveTotestCalciumion(Ca2+)flowattheheadandendofouterhaircells(OHCs)inrestingstateandinresponsetoNimodipinetreatment.MethodsNon-invasivemicro-testtechniqueswereusedtostudyCa2+inisolatedOHCsinadultguineapigs.ResultsFourtypesofCa2+transportwereidentifiedinOHCsonbasilarmembranetissuefragments:influxattheheadofwitheffluxatthebottom(type1):effluxattheheadofOHCswithinfluxatthebottom(type2);influxatthebothheadandbottom(type3);andeffluxatthebothheadandbottom(type4).However,onlytype1andtype3ofCa2+iontransportweredetectedinthecochlea.WeproposethatCa2+iontransportexistsinadultguineapigcochlearOHCsinrestingstateandisvariable.Ca2+flowinOHCcanbeinhibitedbyNimodipineinrestingstate.

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  • 简介:Recently,thehumancochleahasbeenshowntocontainnumerousresidentmacrophagesundersteady-state.Themacrophagesaccumulateinthestriavascularis,amongtheauditorynerves,andarealsospottedinthehumanorganofCorti.ThesemacrophagesmayprocessantigensreachingthecochleabyinvasionofpathogensandinsertionofCIelectrode.Thus,macrophagesexecuteaninnate,andpossiblyanadaptiveimmunity.Here,wedescribethemolecularmarkersCD4andCD8ofTcells,macrophagemarkersMHCⅡandCD11b,aswellasthemicroglialmarkersTEME119andP2Y12,inthehumancochlea.Immunohistochemistryandtheadvantageoussuper-resolutionstructuredilluminationmicroscopy(SR-SIM)wereusedinthestudy.CD4~+andCD8~+cellswerefoundinthehumancochleae.Theywereseeninthemodiolusinasubstantialnumberadjacenttothevessels,intheperipheralregionoftheRosenthal’scanal,andoccasionallyinthespiralligament.Whilethereareasurprisinglylargenumberofmacrophagesinthestriavascularisaswellasbetweentheauditoryneurons,CD4~+andCD8~+cellsarehardlyseenintheseareas,andneitherareseenintheorganofCorti.Inthemodiolus,macrophages,CD4~+andCD8~+cellsappearedofteninclusters.InteractionbetweenthesedifferentcellswaseasilyobservedwithSR-SIM,showingcloselyplacedcellbodies,andtheprocessesfrommacrophagesreachingoutandtouchingthelymphocytes.OtherwisetheCD4~+andCD8~+cellsinhumancochleartissuearediscretelyscattered.Thepossiblerolesoftheseimmunecellsarespeculated.

  • 标签: Macrophage HUMAN COCHLEA CD4 CD8 Lymphocyte
  • 简介:ObjectiveChronictinnitusisahighlyprevalentconditionandhasbeenhypothesizedtoresultfromaninnatedisturbanceincentralnervousserotonergictransmission.Giventhefrequentcomorbiditywithmajordepressionandanxiety,wearguethatcandidategenesforthesedisordersarelikelytooverlap.Thepresentstudyaddressesthegeneencodingforthe5-HT1Areceptorasaputativeriskfactorfortinnitus.MethodsIn88subjectswithadiagnosisofchronicsubjectivetinnituswhounderwentadetailedneurootologicalexamination,theentire5-HT1AgenewasamplifiedusingoverlappingPCRproducts.Ampliconswerecustomsequencedbidirectionallyandwerescreenedforvariantsinmultiplealignmentsagainstthehumangenomereference.ResultsWeidentifiedasynonymousC>Texchangeatresidue184(Pro)in7/88subjects,butdetectednomissensevariantsinthepopulationunderstudy.Specifically,thefollowingresidueswerefullyconserved:16(Pro),22(Gly),28(Ile),98(Val),220(Arg),267(Val),273(Gly),and418(Asn).DiscussionThepresentdatacountagainstthecausationofchronictinnitusbyachangeinthe5-HT1Areceptor'saminoacidsequence.However,theallelefrequencyforthe184Prominorallele(0.04)reachedtwicethefrequencyreportedincontrolcohortsfromthesameethnicity.Additionalinvestigationsareinvitedtoclarifytheroleofthe5-HT1Apolymorphisminlargersamples,andtocontrolforcomorbidaffectivedisorders.

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