双语细菌的感染与免疫

BasictermsBacterialinfection（细菌的感染）Pathogen（病原菌）Nonpathogen（非病原菌）Opportunisticpathogen（机会致病菌）当前1页，总共68页。BacterialInfection细菌的感染Theprocessofbacteriainvadinginthebody,growinginthetissues,producingtoxinsandcausingdiseasesiscalledbacterialinfection.当前2页，总共68页。Pathogen（病原菌）Pathogenicbacterium（致病菌）Abacteriumwhichcancauseadiseaseiscalledpathogen.Nonpathogen（非病原菌）Nonpathogenicbacterium（非致病菌）Abacteriumthatdoesnotcausediseaseiscallednonpathogen.当前3页，总共68页。Opportunisticpathogen（机会致病菌）Conditionedpathogen（条件致病菌）Somebacteriaarecapableofcausingdiseasesonlyundercertainconditions.Theseorganismscancausediseaseonlyifoneormoreoftheusualdefencemechanismshumanshaveevolvedtorestrictmicroorganismsfromtheirusuallysterileinternalorgansandtissuearebreachedbyaccident,byintent(e.g.surgery),orbyanunderlyingmetabolicoraninfectiousdisorder(e.g.AIDS).当前4页，总共68页。OutlineNormalfloraandopportunisticpathogenBacterialpathogenesisThehostimmunedefencesystemTheinitiationandcourseofinfectionHospitalinfection当前5页，总共68页。Section1

Normalfloraandopportunisticpathogen

正常菌群与机会致病菌当前6页，总共68页。★Normalflora（正常菌群）Normalmicrobialflora（正常微生物群）Thepopulationofmicroorganismsthatinhabittheskinandmucousmembranesofhealthypersons.Theyareusuallyharmless,someevenbeneficial,tohuman’shealth.当前7页，总共68页。LocationsSurfacetissuesofskinOralcavityRespiratorytractGastrointestinaltractGenitourinarytract当前8页，总共68页。Normalfloraonintestinalmucosa当前9页，总共68页。肠道的正常菌群当前10页，总共68页。当前11页，总共68页。★BeneficialeffectsofthenormalfloraBiologicalantagonism（生物拮抗）Productionofessentialnutrients（营养作用）Primingofimmunesystem（免疫作用）Anti-aging（抗衰老作用）当前12页，总共68页。Biologicalantagonism(生物拮抗)Biologicalbarriers（生物屏障）orReceptorcompetition（受体竞争)Harmfulmetabolites（有害代谢产物）Nutrientcompetition（营养竞争）当前13页，总共68页。Conditionedpathogen（条件致病菌）Somebacteriaarecapableofcausingdiseasesonlyundercertainconditions.Thesebacteriaarecalledopportunistic(conditioned)pathogensandthiskindofinfectioniscalledopportunisticinfection（机会性感染）.★

Opportunisticpathogen（机会致病菌）当前14页，总共68页。★

ConditionsofopportunisticinfectionChangeofinhabitingplaces（寄居部位改变）Immunesystemcompromise（宿主免疫功能低下）Dysbacteriosis（菌群失调）当前15页，总共68页。Dysbacteriosis（菌群失调）Iffloradisequilibriumoccurs,forexample,whentheresidentfloraisdisturbed,somelittlesignificantmicroorganismsmaycolonize,proliferate,andproducedisease,whichiscalleddysbacteriosis.Dysbacteriosismainlyresultedfromlongtermandlargedosesantibioticstaken.当前16页，总共68页。Superinfection（重叠感染）Afrequentcomplicationofdrugtherapyformicrobialinfection.Itmayresultfromopportunisticcolonizationfollowingimmunosuppressionbytheprimarypathogenandcanbeinfluencedbythetimeintervalbetweeninfections,microbialphysiology,orhostresistance.当前17页，总共68页。Dysbacteriosisandsuperinfection当前18页，总共68页。肠道的正常菌群健康青壮年粪便涂片健康老年粪便涂片（双歧杆菌）当前19页，总共68页。Probiotics（益生菌）当前20页，总共68页。Probiotics（益生菌）&Prebiotics（益生元）当前21页，总共68页。Section2

BacterialPathogenesis

细菌的致病作用BasictermsBacterialPathogenicity

BacterialvirulenceNumberofinvadingorganismsPortalofentry当前22页，总共68页。Pathogenicity（致病性）

isusedtodescribethecapacityofbacteriatoinitiatediseases.Thetermofvirulence（毒力）

isusedasacomparisonofpathogenicityinthequantitativesense.ID50（medianinfectiousdose,半数感染量）:Infectiousdoseofbacteriafor50%ofthetestpopulation.LD50

（medianlethaldose,半数致死量）

:Lethaldoseofbacteriafor50%ofthetestpopulation.BasicTerms当前23页，总共68页。ExotoxinPili(Fimbrial)CapsuleVirulentEnzymeAdhesinsFlagellaIronbindingproteinVirulencesurfaceproteinBacterialvirulencefactors（细菌毒力因子）当前24页，总共68页。Bacterialvirulence（细菌的毒力）Virulence（毒力）Invasiveness（侵袭力）Toxin（毒素）Adherence&permanentplanting（黏附与定植）Multiplication&diffusion（增殖与扩散）Anti-defensefunctionofhost（免疫逃逸）Endotoxin（内毒素）Exotoxin（外毒素）当前25页，总共68页。Adhesionandfieldplanting（黏附与定植）Invasion（侵入）Multiplicationanddiffusion（繁殖与扩散）Localdiffusion（局部扩散）Systemicdiffusion（全身性扩散）当前26页，总共68页。★Invasiveness（侵袭力）Definition:Bacterialcapabilitythatcanbreakthroughthephysiologicbarriers(skin,mucosa),settledown,multiply,andspreadinthehost.Adhesivefactors:adhesinandcapsuleInvasivesubstancesBacterialbiofilm当前27页，总共68页。1.Adhesin（黏附素）Protiensonbacterialsurfaceassociatedwithadhesion.Adhesinsbindtoadhesinreceptorsonhostcells.Classification:Pilus(fimbriae)adhesin(菌毛黏附素)Non-fimbriaeadhesin(非菌毛黏附素)当前28页，总共68页。AdhesinAdhesinEpitheliumReceptorBacterium当前29页，总共68页。Capsule(荚膜)ofstreptococcuspneumoniaeMicrocapsule（微荚膜）

Slimelayer（黏液层）当前30页，总共68页。ProtectthecellwallagainstattackbydrugsInhibitingestionandkillingbyphagocytesPlayaroleintheadherenceofhumantissueAntigenicity2.Capsule（荚膜）当前31页，总共68页。3.Invasiveenzymes侵袭性酶类Somebacteriamaygenerateinvasiveenzymes,whichcandamagebodytissuesandpromotetheinvasionanddiffusionofthebacteria.当前32页，总共68页。4.Invasin侵袭素Encodedbyinvasivegenes（侵袭基因）Mediateinvadingadjacentepithelialcells当前33页，总共68页。5.Bacterialbiofilm细菌生物被膜：Themembraneousbacterialcommunitycomposedofbacteriaandtheextracellularpolymerssecretedbybacteriaaftertheyadheretothesurfaceoflivingornonlivingmaterials.当前34页，总共68页。5.Bacterialbiofilm细菌生物被膜FacilitatesbacterialadhesionBafflesthepenetrationofantibioticandtherejectionofimmunesystemProfitssignalcommunicationamongbacteria.当前35页，总共68页。Bacterialbiofilm当前36页，总共68页。当前37页，总共68页。Biofilmintheendoscope（内窥镜）当前38页，总共68页。Staphylococcusepidermidis（表皮葡萄球菌）biofilminthesurfaceofvenouscatheter（静脉导管）当前39页，总共68页。ExotoxinsEndotoxinsExcretedbylivingcells;highconcentrationsinliquidmedium.IntegralpartofthecellwallofG-bacteria.Releasedonbacterialdeathandinpartduringgrowth.Maynotneedtobereleasedtohavebiologicactivity.ProducedbybothG+andG-bacteria.FoundonlyinG-bacteria.PolypeptidesLPS(lipidAportionprobablyresponsiblefortoxicity.)Relativelyunstable;toxicityoftendestroyedrapidlybyheatingattemperaturesabove60℃.Relativelystable;withstandheatingattemperaturesabove60℃forhourswithoutlossoftoxicity.当前40页，总共68页。ExotoxinsEndotoxinsHighlyantigenic;stimulateformationofhigh-titerantitoxin(抗毒素).Antitoxinneutralizestoxin.Weaklyimmunogenic;antibodiesareantitoxicandprotective.Relationshipbetweenantibodytitersandprotectionfromdiseaseislessclearthanwithexotoxins.Convertedtoantigenic,nontoxictoxoids(类毒素)byformalin,acid,heat,etc.Toxoidsareusedtoimmunize.Notconvertedtotoxoids.Highlytoxic;fataltoanimalsinmicrogramquantitiesorless.Moderatelytoxic;fatalforanimalsintenstohundredsofmicrograms.当前41页，总共68页。ExotoxinsEndotoxinsUsuallybindtospecificreceptorsoncells.Specificreceptorsnotfoundoncells.Usuallydonotproducefeverinthehost.Selectivetoxicityandspecificclinicalsyndromes.Neurotoxins(神经毒素)Cytotoxins(细胞毒素)Enterotoxins(肠毒素)UsuallyproducefeverinthehostbyreleaseofIL-1andothermediators.Frequentlycontrolledbyextrachromosomalgenes(e.g.plasmids).Synthesisdirectedbychromosomalgenes.当前42页，总共68页。区别要点外毒素内毒素来源革兰阳性菌与部分革兰阴性菌革兰阴性菌编码基因质粒、前噬菌体或染色体基因染色体基因存在部分从活菌分泌出，少数菌崩解后释出细胞壁组分，菌裂解后释出化学成分蛋白质脂多糖稳定性60～80℃，30分钟破坏160℃，2～4小时破坏毒性作用强，对组织器官有选择性毒害效应，引起特殊的临床表现较弱，各菌的毒性效应大致相同，引起发热、白细胞增多、微循环障碍、休克、DIC等抗原性强，刺激机体产生抗毒素；甲醛液处理脱毒形成类毒素弱，刺激机体产生的中和抗体作用弱；甲醛液不能脱毒形成类毒素当前43页，总共68页。SpecificpolysaccharideLPS当前44页，总共68页。Procedure当前45页，总共68页。Neurotoxin（神经毒素）Tetanustoxin（破伤风毒素）当前46页，总共68页。Cytotoxins（细胞毒素）Diphtheriatoxin（白喉毒素）inhibitsproteinsynthesisinmammaliancellsandcausesnecrosisofcellsDiphtheriamembraneonthroat当前47页，总共68页。Enterotoxin（肠毒素）Choleraenterotoxin当前48页，总共68页。BiologicalrolesofendotoxinFever（发热）Leukopeniaandleukocytosis（白细胞反应）Endotoxemiaandshock（内毒素血症与休克）当前49页，总共68页。EndotoxinActivatesmacrophagesActivatescomplementActivatesHagemanfactorIL-1,TNF,NitricoxideFeverandhypotensionC3a,C5aHypotensionEdemaCoagulationcascadeDIC当前50页，总共68页。Section4

theinitiationandprocessofinfectionSourcesofinfectionPathwayofbacterialentranceTypesofbacterialinfection当前51页，总共68页。Exogenousinfection（外源性感染）PatientsCarriers（带菌者）AnimalsEnodogenousinfection（内源性感染）OpportunisticpathogensSourcesofinfection当前52页，总共68页。Pathwayofpathogenentrance

RespiratoryGastrointestinalGenitalSkinandmucosaAnimalbitesBloodSexualtransmission当前53页，总共68页。TypesofbacterialinfectionInapparentinfection（隐性感染）Apparentinfection（显性感染）Carrierstate（带菌状态）当前54页，总共68页。Inapparentinfection（隐性感染）Subclinicalinfection（亚临床型感染）Aninfectionthathasnoobservablesymptoms.Itoccurswhenthehostimmunityispotentorthepathogenicityofthepathogenisweak.当前55页，总共68页。Thetipoftheiceberg

当前56页，总共68页。Apparentinfection（显性感染）AcuteinfectionChronicinfectionLocalinfectionGeneralizedinfection★Toxemia(毒血症)Endotoxemia(内毒素血症)Bacteremia(菌血症)Septicemia(败血症)Pyemia(脓毒血症)当前57页，总共68页。Toxemia（毒血症）Bacteriamutiplyatinvadinglocationanddonotenterbloodstream,buttheexotoxins（外毒素）enterbloodandcausecorrespondingtoxicsymptoms.Endotoxemia（内毒素血症）Gram-negativebacteriamutiplyatlocationorinbloodstream,releasealotofamountendotoxin（内毒素）releasedfrombacterialcellrupture.当前58页，总共68页。Bacteremia（菌血症）Afterenteringblood,bacteriacirculatebutnotmultiplyintheblood.Septicemia（败血症）Bacteriacirculateandmultiplyintheblood,inwhichbacteriaproducetoxicproductsandcausehighswingingtypeoffeverandothertoxicsymptoms.当前59页，总共68页。Pyemia（脓毒血症）Pyogenic（化脓性）bacteriaproducesepticemiawithmultipleabscesses（脓肿）ininternalorganssuchasspleen,liverandkidneys.当前60页，总共68页。★

Carrierstate（带菌状态）Afterinapparentinfectionorapparentinfection,sometimesthepathogensarenoteliminatedintime,sothebacteriawillsurviveandmultiplyinhostatlowspeed,andbacteriaspreadintotheenvironment.Carrier（带菌者）isimportantsourceofinfection.当前61页，总共68页。HospitalinfectionDefinitionBasiccharacteristicsClassificationMicrobialecologicalcharacteristicsEpidemiological