航天医学基础-introductiontospacelifesciences课件

IntroductiontoSpaceLifeSciencesGillesClément,Ph.DCNRS"CerveauetCognition"LaboratoryToulouse,FranceKluwerAcademicPublishers•Copyright©2003•AllrightsreservedFundamentalsofSpaceMedicine—Chapter1KeyConceptsSpaceLifeSciences:Whatisit? WhereweareThehistoricalcontextofhumanspaceflightHowwegotthereTheimportanceofcontinuingresearchbeforelong-durationexplorationmissionscanbesafelyundertaken WheredowegofromhereSpaceLifeSciences—WhatisitLifeSciences

arespecificallydevotedtotheworkingofthelivingworld(frombacteriaandplantstohumans)OnEarth,alllivingorganismshavedevelopedasaresultofconstantexposureto1-ggravitySpaceLifeSciencesopenadoortounderstandingourselves,ourevolution,theworkingofourworldwithouttheconstrainingbarrierofgravityBesidemicrogravity,duringspaceflightlivingorganismsarealsoaffectedbyionizing

radiation,

isolation,confinement,

changesin

circadianrhythms

(24-hrday/nightcycle),etc.Objectivesofspacelifesciences:EnhancefundamentalknowledgeincellbiologyandhumanphysiologyProtectthehealthofastronautsDevelopadvancedtechnologyandapplicationsforspaceandground-basedresearchSpaceMedicineversusSpacePhysiologySpaceMedicineTosolvemedicalproblemsencounteredinspaceflightIncludessomeadaptivechanges(e.g.,spacemotionsickness),environmentalexposures,etc.Includesalsosomenon-pathologicchangeswhichbecomemaladaptiveonreturntoEarth(e.g.,boneloss)Outlookisoperational,viewsproblems/peculiaritiesfromstandpointofmissionimpactSpacePhysiologyTocharacterizeresponsetospace,especially0-GNecessaryknowledgebaseforaboveOutlookisinvestigational,viewsproblems/peculiaritiesfromstandpointofscientificreturn

Whereweare(asof1stJuly‘03)PhotoCNESTotalnumberofpersonswhohaveflowninspace:433(41)Cumulativespaceflighttime:72years(26.410days)Meanspaceflightduration:28daysCumulativespaceflightdurationbyindividual:Polyakov(679days;2flights)Avdeyev(748days;3flights)Re-adaptationtoEarthgravitystated "tobe90%complete

[after6years]" —ValeryPolyakov(during ascienceconference)Howdidwegetthere?22months25months1783:TwoFrenchgentlemenrideahot-air(Montgolfier)balloonMajorSpaceLifeSciencesEvents1951:Firstsuccessful(non-orbital)flightofasounding rocketwithamonkeyand11mice(previous attemptssince1948werenotsuccessful)1957:DogLaikafirstlivingcreatureintoorbit(died afterafewdays)—followedbymonkeysPhotoNASAPhotoNASAPhotoCNES1965:Firstspacewalk(Extra-VehicularActivity)1961:FirsthumantoorbittheEarth (Y.Gagarin)1963:Firstwoman(V.Tereshkova) inspace—secondRussian woman(S.Savitskaya)did notflyuntil1982MajorSpaceLifeSciencesEventsPhotoNASAPhotoCNES1965-66:Longeststayinspaceis14days(Gemini7) —firstobservationsonhumanbodyadaptation —artificialgravityfirsttested(Gemini11)MajorSpaceLifeSciencesEvents70’s:Salyut,Skylab—startofdetailedSLSinvestigations1981:Firstspacevehiclepilotedduringreturn(Shuttle)PhotosNASA2000:FirstexpeditioncrewonboardISS1994:Longeststayinspaceis14months(MIR)HumanSpaceflightExperienceAdaptedfromReschkeandSawin(2003)HumansinSpaceFirstspacemissionsweretodemonstratethathumanscouldsurviveajourneyintospaceSomepeopledoubtedwhetherhumanscouldendurethegforcesoflaunchandre-entry,orswallow,orsleepintheabsenceofgravitySomepredictedthat"thebowelswouldnotworkwithoutgravity,theheartmightcavitatelikeapump,orbecomesoweakenedastoprohibitreturntoEarth"Howlongcanhumansliveinspace,andhoweffectivelycantheyworkinspacearestillopenquestionsLivingandworkingisfardifferentfrommerelysurvivingAfterextendedstaysinspace,canpeoplereturnsafelytoEarthandleadnormal,healthylives?SuchquestionsaremuchmoredifficultthanquestionsofsurvivalbecausetheyrequiresophisticatedscientificexperimentationMovie:13_impossiSurvivingtheOdysseyWhatReallyOccursNoupordown—disorientation,nauseaFluidsshifttowardshead—«

puffy

»face,sinuscongestion,headache,changesinsmellandtasteAntigravitypostural(extensor)musclesnotused—newlocomotionpattern,«

chicken

»legs,musclestrengthandendurancedecreasePhotosNASAWhatReallyOccursIntervertebratediskslesscompressed—heightincreases,backpainSleepdisordersNoupordown—disorientation,nauseaFluidsshifttowardshead—«

puffy

»face,sinuscongestion,headache,changesinsmellandtasteAntigravitypostural(extensor)musclesnotused—newlocomotionpattern,«

chicken

»legs,musclestrengthandendurancedecreaseFluidsvolumedecreases—changesinheartrateandbloodpressure,breathingdifficult(lessredbloodcells)BonelossAdaptedfromLujanandWhite(1994)PhotoNASANoupordown—disorientation,nauseaFluidsshifttowardshead—«

puffy

»face,sinuscongestion,headache,changesinsmellandtasteAntigravitypostural(extensor)musclesnotused—newlocomotionpattern,«

chicken

»legs,musclestrengthandendurancedecreaseFluidsvolumedecreases—changesinheartrateandbloodpressure,breathingdifficult(lessredbloodcells)BonelossIntervertebratediskslesscompressed — heightincreases,backpainSleepdisordersWhatReallyOccursPsychologicaltroublesSharpervision,butlightflashes(radiation)PhotoNASAPhotoNASAIssuesforHumanMissionsPreflight:Astronautselection,crewselection,medicaltrainingInflight:Acceleration,vibration,noise duringlaunchandlandingSoyuzShuttleMovie:19_launchIssuesforHumanMissionsPostflight:Piloting"1-gfeelslike4-g"EmergencyegressStanding:orthostaticintoleranceWalking:posturalinstabilityMotionsickness (MaldeDébarquement)

MuscleandboneweaknessDecreasedexercisecapacityReturntoflightstatusPhotoNASACountermeasures2daily1-hoursessionsofexercise:TreadmillwithaxialloadingCycleergometerResistiveexerciseTractionon“bungeecords”LowBodyNegativePressureFluidloadingbeforere-entryPhotosNASAHumanMarsMissionSpaceflightLifeSupportHumanrequirementsHygiene,sanitationNutrition(adequate,appealing)Rest(avoidchronicfatigue)Exercise(fitness,recreation,motivation)Humanperformance(psycho- social,workload,circadianfactors)LifesupportsystemsAtmosphere,temperature,lighting,noiseFood,wasteFromphysico-chemical(recycled)tobioregenerative(ecologicallyclosed)Biosphere2MirGreenhouseBio-PlexPhotoNASAPhotoESAGreenhouseinSpaceCriticalquestionstobeaddressed:Howfarcanwereducerelianceonexpendables?Howwelldobiologicalandphysico-chemicallifesupporttechnologiesworktogetheroverlongperiodsoftime?Isa“steadystate”conditioneverachievedwithbiologicalsystems?Howdovariouscontaminantsaccumulateandwhatarethelong-termcleanlinessissues?PhotoNASAFutureResearchChangesseenatcellularlevel. However,toomuchpublicityonbiochemicalfactoriesinspacePlantsinspace.Lifesupportsystems:howtomovefromphysico-chemicaltoclosedecologicallifesupportsystemsHumanMarsmission.ProbablythelongestperiodawayfromEarthtodate;alsoprobablythelongestexposuretohypogravity(1/3g)environmenttodateThinkaboutdevelopmentofinsects, amphibians,mammalsafterseveral generationswithoutperceivedgravitySpaceLifeSciencesresearchisonholdnowISSshouldbeidealforstudyoffundamentalbiologicalprocesses—newscience:gravitationalphysiology;noNobelprizeyet,butgivenprizeshavebeenchallengedDocumentNASDAPhotoNASAMovie:29_frogBenefitsofSLSResearchBiologyImproveoverallhealthofpeopleofallagesImprovecropyieldsusinglessnutrientsandsmallersurfaceAdvanceunderstandingofcellbehaviorBiotechnologyProvideinformationtodesignanewclassofdrugstotargetspecificproteinsandcurespecificdiseasesCulturetissueforuseincancerresearch/surgeryandboneandcartilageinjuriesBiomedicalResearchEnhancemedicalunderstandingoftheroleofforceonboneindiseaseprocessesincludingosteoporosis(boneloss)Advancefundamentalunderstandingofthebrainandnervoussystemandhelpdevelopnewmethodstopreventandtreatvariousneurologicaldis