AndI'mBobDoughty.TodaywetellaboutAlzheimer'sdisease（阿尔茨海默病）.Onecenturyafteritsdiscovery,thediseaseisstilldestroyingpeople'sbrains.Thecauseremainsunknown.知识扩展：阿尔茨海默病疾病描述
是一组病因的原发性退行性脑变性疾病。多起病于老年期，潜隐起病，病程缓慢且不可逆，临床上以智能损害为主。病理改变主要为皮质弥漫性萎缩，沟回增宽，脑室扩大，神经元大量减少，并可见老年斑（SP），神经原纤维结（NFT）等病变，胆碱乙酰化酶及乙酰胆碱含量显著减少。起病在65岁以前者旧称老年前期痴呆，或早老性痴呆，多有同病家族史，病情发展较快，颞叶及顶叶病变较显著，常有失语和失用。
AUnitedStatesSenatecommitteemetlastmonthtodiscusstheissueofAlzheimer'sdisease.TheSenateSpecialCommitteeonAgingheardfromseveralspeakers,includingretiredSupremeCourtJusticeSandraDayO'Connor.SheurgedCongresstosupportanaggressivecampaignagainstthedisease.
MizO'ConnorwasthefirstwomantoserveonAmerica'shighestcourt.Butsheleftthecourtintwothousandsix.HerhusbandJohnsuffersfromAlzheimer's.Sheneededtimetomovehimtoanassistedcarecenter.
AboutfivehundredthousandpeopleintheUnitedStatesalonehavethisheartbreakingdisease.Millionsmoreareexpectedtohaveitinyearstocome.
DoctorsdescribeAlzheimer'sasaslowlyincreasingbraindisorder.Itaffectsmemoryandpersonality--thosequalitiesthatmakeapersonanindividual.Thereisnoknowncure.Victimsslowlylosetheirabilitiestodealwitheverydaylife.Atfirst,theyforgetsimplethings,likewheretheyputsomethingoraperson'sname.
Astimepasses,theyforgetmoreandmore.Theyforgetthenamesoftheirhusbands,wivesorchildren.Thentheyforgetwhotheyare.Finally,theyremembernothing.Itisasiftheirbraindiesbeforetheotherpartsofthebody.VictimsofAlzheimer'sdodiefromthedisease,butitmaytakemanyyears.
Alzheimer'sdiseaseisthemostcommondisabilityormentalsicknesscalleddementia.Dementiaisthelossofthinkingabilitythatissevereenoughtointerferewithdailyactivities.Itisnotadiseaseitself.Instead,dementiaisagroupofsignsofsomeconditionsanddiseases.
Somekindsofdementiacanbecuredorcorrected.Thisisespeciallytrueiftheyresultfromdrugs,infection,sightorhearingproblems,headinjury,andheartorlungproblems.Otherkindsofdementiacanbecorrectedbychanginglevelsofhormonesorvitaminsinthebody.However,braincellsofAlzheimer'svictimsdieandarenotreplaced.
Victimscanbecomeangryandviolentastheabilitytothinkandrememberdecreases.Oftentheyshoutandmovewithnopurposeorgoal.Mediareportsoftentellaboutolderadultsfoundwalkinginplacesfarfromtheirhomes.Theydonotknowwheretheyareorwheretheycamefrom.Generally,thesepeoplearesufferingfromAlzheimer'sdisease.
Alzheimer'sgenerallydevelopsdifferentlyineachperson.Yetsomeearlysignsofthediseasearecommon.Often,thevictimsmaynotrecognizechangesinthemselves.Othersseethechangesandstruggletohidethem.
Probablythemostcommonearlysignisshort-termmemoryloss.Thevictimcannotremembersomethingthathappenedyesterday,forexample.Also,victimsofthediseasehaveincreasingdifficultylearningandstoringnewinformation.Slowly,thinkingbecomesmuchmoredifficult.Thevictimscannotunderstandajoke,orcannotcookameal,orperformsimplework.
AnothersignofAlzheimer'sdiseaseisdifficultysolvingsimpleproblems.Alzheimer'spatientsmightnotknowwhattodoiffoodonastoveisburning.Also,peoplehavetroublefollowingdirectionsorfindingtheirwaytonearbyplaces.
Anothersignisstrugglingtofindtherightwordstoexpressthoughtsorunderstandwhatisbeingdiscussed.Finally,peoplewithAlzheimer'sseemtochange.Quietpeoplemaybecomenoisyandaggressive.Theymayeasilybecomeangryandlosetheirabilitytotrustothers.
Alzheimer'sdiseasenormallyaffectspeoplemorethansixty-fiveyearsold.Butrarecaseshavebeendiscoveredinpeopleyoungerthanfifty.
Alzheimer'sisidentifiedinonlyabouttwopercentofpeoplewhoaresixty-five.Buttheriskincreasestoabouttwentypercentbyageeighty.Byninety,halfofallpeoplearefoundtohavesomesignsofthedisease.
Alzheimer'saffectspeopleofallracesequally.Yetwomenaremorelikelytodevelopthediseasethanmen.Thisispartlybecausewomengenerallylivelongerthanmen.
Thereisnoone,simpletesttoshowifsomeonehasAlzheimer'sdisease.Socialworkersandmentalhealthexpertssometimestestformemoryandjudgment.Patientsmaybeaskedtoidentifysmellssuchassmoke,naturalgasorfruits.Somescientistssayaweakenedabilitytoidentifysmellsmaybeinvolved.TheybelieveitmightshowpossibledevelopmentofAlzheimer's.
MedicaldoctorswhosuspectapatienthasAlzheimer'smusttestthepersonformanyotherphysicalproblemsfirst.Alzheimer'sisconsideredifthetestsfailtoshowtheexistenceofotherproblems.TheonlywaytobesureapersonhasAlzheimer'sistoexaminethevictim'sbrainafterdeath.
PeoplewhocareforAlzheimer'spatientsmaybecomeextremelytiredphysicallyandemotionally.Familiesoftencangetadviceandemotionalsupportfromlocalgroups.TheAlzheimer'sDiseaseEducationandReferralCenterandTheAlzheimer'sAssociationprovideinformationandsupport.
Patientscannotfullyrecoverfromthedisease.Butmanycanbehelpedbymedicine.Thatisespeciallytrueifthediseaseisfoundearly.
America'sFoodandDrugAdministrationhasapprovedseveraldrugstotreatsignsofthedisease.Thedrugsareoftwokinds.Adoctormustorderthesemedicinesforpatients.
Mostarecalledcholinesteraseinhibitors.Cholinesteraseinhibitorsmayworkbyprotectingachemicalmessengerneededforbrainactivities.Theyaremeanttotreatmemory,thinking,language,judgmentandotherbrainactivity.Theyareusedformildtomoderatecasesofthedisease.
Thesecondkindofdrughasalongname.Itisrepresentedbythedrugmemantine.Thismedicineseemstoworkbygoverningtheactivityofachemicalinvolvedininformationprocessing,storageandmemory.IttreatspatientswithmoderatetosevereAlzheimer's.
BritishwriterIrisMurdochdiedofAlzheimer'sdisease.Shesaiditwasadarkandterribleplace.
Thetwothousandsevenfilm,"AwayfromHer"tellswhathappenstoonemarriagewhenapartnersuffersfromAlzheimer'sDisease.JulieChristiewasnominatedfortheAcademyAwardforBestActressforplayingthepatient.Listenasshedescribesthepainofhermentalcondition.
IthasbeenmorethanacenturysinceaGermandoctor,AloisAlzheimer,toldaboutadementiapatientwhosebrainwasstudiedafterdeath.Herbrainhadstickystructuresandnervecellsthatappearedtobemixedtogether.Laterstudiesshowedthesenervesaremadeofaproteincalledtau.Thetauproteinchangessothatitstickstogetheringroups.Thestickystructureswereshowntobeamyloidplaques.
ScientistsarestillnotsurewhatcausesAlzheimer'sdisease.Theleadingtheoryblamesamyloidplaques.
NotallscientistsaresurethatamyloidplaquescauseAlzheimer's.Somesaytheplaquescouldbeaneffectofthedisease,notthecause.ReportssaysomepeoplewhodieofAlzheimer'sdonothaveanyplaquesintheirbrains.Otherswhohavethestickystructuresshowednosignsofthedisease.
Otherpossibilitiesaresometimesnoted.Theseincludestudiesofenzymesthatactonproteinstoproducetheplaques,andusingantibodiesagainstamyloid.Yetamyloidandenzymesareimportantforhealth.Scientistsdonotwanttodestroythemcompletely.
OtherscientistsareworkingwithagenecalledapoE4.Researchersfoundinnineteenninety-threethatitspresenceincreasesthechanceofdevelopingAlzheimer'sdisease.
ManymorestudiesarebeingdonetofindthecauseandtreatmentsforAlzheimer's.Itisadiseasethatcontinuestoaffectmillionsofpeoplearoundtheworld.
ThisSCIENCEINTHENEWSprogramwaswrittenbyJerilynWatson.OurproducerwasBriannaBlake.ThisisBobDoughty.
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