Skin皮膚專題知識講座

TheskinandSkinRegenerativeMedicineSkin皮膚專題知識講座第1頁KayiName?Skin皮膚專題知識講座第2頁Skin皮膚專題知識講座第3頁AgingskinSkin皮膚專題知識講座第4頁skin

thelargestorganinthebodyprotectsenseregulatetemperatureProductionofVitaminDClininiansDermatology-----dermatologistPlasticandestheticsurgery------plasticsurgeonSkin皮膚專題知識講座第5頁KeratinocytefibroblastSkin皮膚專題知識講座第6頁OBJECTIVEMaster

skinstructureandfunction

epidermis-----keratinization:proliferation/differentiationAcquaitanceAnomaliesofskin----commonskindiseases

AdvanceSkinregenerativemedicineSkin皮膚專題知識講座第7頁INTRODUCTIONepidermisdermishypodermisSkin皮膚專題知識講座第8頁DermisPapillarylayer+Reticularlayer第二節(jié)真皮Skin皮膚專題知識講座第9頁skindermis真皮papillarylayer乳頭層reticularlayer網(wǎng)織層appendages從屬器hair毛sebaceousgland皮脂腺sweatgland汗腺THESTRUCTUREOFSKINepidermis表皮stratumcorneum角質(zhì)層stratumlucidum(透明層)stratumgranulosum顆粒層stratumspinosum棘層stratumbasale基底層nail指(趾)甲Skin皮膚專題知識講座第10頁EPIDERMIS主要細(xì)胞組成keratinocyte(角質(zhì)形成細(xì)胞)non-keratinocyte(非角質(zhì)形成細(xì)胞)differentiationstratumcorneum角質(zhì)層

stratumgranulosum顆粒層stratumlucidum(透明層)

stratificationstratumbasale基底層stratumspinosum棘層Skin皮膚專題知識講座第11頁（一）EpidermalstratificationanddifferentiationSkin皮膚專題知識講座第12頁PSORIASIS銀屑病redandwhitehuesofscalypatchesappearingonthetopfirstlayeroftheepidermis(skin).Skin皮膚專題知識講座第13頁Langerhanscell(郞格漢斯細(xì)胞)Langerhanscellsaredendriticcells(antigen-presentingimmunecells)oftheskinandmucosa,andcontainlargegranulescalledBirbeckgranules.Theyarepresentinalllayersoftheepidermis,butaremostprominentinthestratumspinosum.Inskin

infections,thelocalLangerhanscellstakeupandprocessmicrobial

antigenstobecomefullyfunctionalantigen-presentingcells.Langerhanscellsderivefromthecellulardifferentiationofmonocyteswiththemarker"Gr-1"(alsoknownas"Ly-6G/Ly-6C").Thisdifferentiationrequiresstimulationbycolonystimulatingfactor(CSF)-1.6Theyaresimilarinmorphologyandfunctiontomacrophages.Skin皮膚專題知識講座第14頁Albinoslackanenzymecalledtyrosinase.Tyrosinaseisrequiredformelanocytestoproducemelaninfromtheaminoacid

tyrosine

melanocyte(黑素細(xì)胞)Melanocytesaremelanin-producingcellslocatedinthebottomlayer(thestratumbasale)oftheskin'sepidermis,themiddlelayeroftheeye(theuvea),theinnerear,meninges,Melaninisapigmentthatisresponsibleprimarilyforthecolorofskin.Skin皮膚專題知識講座第15頁Skin皮膚專題知識講座第16頁Nodifferenceinmelanocytenumberbetweenspecies.Thedistributionandtyrosinaseactivity!Skin皮膚專題知識講座第17頁Skin皮膚專題知識講座第18頁Melanoma(黑色素瘤):4%ofalldiagnosedskincancers,melanomabeginsinthemelanocytes,cellswithintheepidermisthatgiveskinitscolor.Melanomahasbeencoined“themostlethalformofskincancer”becauseitcanrapidlyspreadtothelymphsystemandinternalorgans.Withearlydetectionandpropertreatment,thecurerateformelanomaisabout95%.Onceitsspreads,theprognosisispoor.Melanomamostoftendevelopsinapre-existingmoleorlookslikeanewmole,whichiswhyitisimportantforpeopletoknowwhattheirmoleslooklikeandbeabletodetectchangestoexistingmolesandspotnewmoles.

Skin皮膚專題知識講座第19頁TheHair

SebaceousGlands

SweatGlands

TheNails

TheAccessaryStructuresoftheSkinSkin皮膚專題知識講座第20頁Skin皮膚專題知識講座第21頁Acnevulgaris(orcysticacne)isacommondisease,characterizedbyareasofskinwithscalyredskin,blackheadsandwhiteheads,pinheads,pimples,nodulesandpossiblyscarring.Acneaffectsmostlyskinwiththedensestpopulationofsebaceousfollicles;theseareasincludetheface,theupperpartofthechest,andtheback.Severeacneisinflammatory,butacnecanalsomanifestinnoninflammatoryforms.2Thelesionsarecausedbychangesinpilosebaceousunits,skinstructuresconsistingofahairfollicleanditsassociatedsebaceousgland,changesthatrequireandrogenstimulation.Acneoccursmostcommonlyduringadolescence,andoftencontinuesintoadulthood.Inadolescence,acneisusuallycausedbyanincreaseintestosterone,whichpeopleofbothgendersaccrueduringpuberty.Skin皮膚專題知識講座第22頁AlopeciaTotalis(全頭脫毛癥）Alopeciameanslossofhairfromtheheadorbody.baldness,Skin皮膚專題知識講座第23頁Skin皮膚專題知識講座第24頁Hemidesmosomes(HD)areverysmallstud-orrivet-likestructuresontheinnerbasalsurfaceofkeratinocytesintheepidermisofskin.Theyaresimilarinformtodesmosomeswhenvisualizedbyelectronmicroscopy.Whiledesmosomeslinktwocellstogether,hemidesmosomesattachonecelltotheextracellularmatrix.Skin皮膚專題知識講座第25頁Skin皮膚專題知識講座第26頁Desmosomesaremolecularcomplexesofcelladhesionproteinsandlinkingproteinsthatattachthecellsurfaceadhesionproteinstointracellularkeratin

cytoskeletalfilaments.Thecelladhesionproteinsofthedesmosome,desmogleinanddesmocollin,aremembersofthecadherinfamilyofcelladhesionmolecules.Theyaretransmembraneproteinsthatbridgethespacebetweenadjacentepithelialcellsbywayofhomophilicbindingoftheirextracellulardomainstootherdesmosomalcadherinsontheadjacentcell.Bothhavefiveextracellulardomains,andhavecalcium-bindingmotifs.Skin皮膚專題知識講座第27頁Age-associatedskinchangesincludethinning,skinlaxity,fragility,andwrinkles.Sun-exposedareasdemonstrateadditionalagingchanges,includingdyspigmentation,prematurewrinkling,telangiectasia,andactinicelastosis.UVA400–315nmUVB315–280nmThesunemitsultravioletradiationintheUVA,UVB,andUVCbands.TheEarth'sozonelayerblocks97–99%ofthisUVradiationfrompenetratingthroughtheatmosphere.OftheultravioletradiationthatreachestheEarth'ssurface,98.7%isUVAPhotoagingSkin皮膚專題知識講座第28頁UVandmolecularandgeneticchangesUVBrayisconsideredasaprimarymutagenthatcanonlypenetratethroughtheepidermaloroutermostlayeroftheskin,resultinginDNAmutations.Theepidermallayerdoesnotcontainanybloodvesselsornerveendingsbutmelanocytesandbasalcellsareembeddedinthislayer.UponexposuretoUVBrays,melanocyteswillproducemelanin,apigmentthatgivestheskinitscolortone.However,UVBwillcausetheformationoffrecklesanddarkspots,bothofwhicharesymptomsofphotoaging.WithconstantexposuretoUVBrays,signsofphotoagingmightappearandprecancerouslesionsorskincancermaydevelop.UVAraysareabletopenetratedeeperintotheskinascomparedtoUVBrays.Hence,inadditiontotheepidermallayer,thedermallayerwillalsobedamaged.Thedermisisthesecondmajorlayeroftheskinanditcomprisescollagen,elastin,andextrafibrillarmatrixwhichprovidesstructuralsupporttotheskin.However,withconstantUVAexposure,thesizeofthedermislayerwillbereduced,therebycausingtheepidermistostartdroopingoffthebody.Duetothepresenceofbloodvesselsinthedermis,UVArayscouldleadtodilatedorbrokenbloodvesselsmostcommonlyvisibleonthenoseandcheeks.Skin皮膚專題知識講座第29頁Skin皮膚專題知識講座第30頁Photoaging:telangiectasia,pigmentationSkin皮膚專題知識講座第31頁SunscreenSPF:ratiooftheminimalerythemadose(MED)ofsunscreen-protectedskinovertheMEDofunprotectedskin.CurrentlyavailableproductsofferexcellentprotectionfromUVBand,toamorevariableextent,fromUVA;therefore,