医学英语-皮肤系统Skin#.ppt

TheskinandSkinRegenerativeMedicine再生医学 LujunYangBurnsandPlasticsuregeryCenterforTranslationalmedicine2ndHospitalofShantouUniversity Kayi Name Agingskin skin thelargestorganinthebodyprotectsenseregulatetemperatureProductionofVitaminD Clininians Dermatology dermatologistPlasticandestheticsurgery plasticsurgeon Keratinocytefibroblast OBJECTIVE Masterskinstructureandfunctionepidermis keratinization角化作用 proliferation增殖 differentiation分化 AcquaitanceAnomalies异常现象ofskin commonskindiseases AdvanceSkinregenerativemedicine皮肤再生医学 INTRODUCTION epidermis dermis hypodermis Dermis真皮 Papillarylayer乳头层 Reticularlayer网状层 第二节真皮 epidermis hypodermis dermis skin dermis真皮 papillarylayer乳头层 reticularlayer网织层 appendages附属器 hair毛 sebaceousgland皮脂腺 sweatgland汗腺 THESTRUCTUREOFSKIN epidermis表皮 nail指 趾 甲 EPIDERMIS 主要细胞组成keratinocyte 角质形成细胞 non keratinocyte 非角质形成细胞 differentiation stratumcorneum角质层 一 Epidermalstratificationanddifferentiation PSORIASIS银屑病 redandwhitehuesofscalypatchesappearingonthetopfirstlayeroftheepidermis skin Langerhanscell 郞格汉斯细胞 Langerhanscellsaredendriticcells antigen presentingimmunecells oftheskinandmucosa andcontainlargegranulescalledBirbeckgranules Theyarepresentinalllayersoftheepidermis butaremostprominentinthestratumspinosum Inskininfections thelocalLangerhanscellstakeupandprocessmicrobialantigenstobecomefullyfunctionalantigen presentingcells Langerhanscellsderivefromthecellulardifferentiationofmonocyteswiththemarker Gr 1 alsoknownas Ly 6G Ly 6C Thisdifferentiationrequiresstimulationbycolonystimulatingfactor CSF 1 6Theyaresimilarinmorphologyandfunctiontomacrophages Albinoslackanenzymecalledtyrosinase络氨酸酶 Tyrosinaseisrequiredformelanocytestoproducemelaninfromtheaminoacidtyrosine melanocyte 黑素细胞 Melanocytesaremelanin producingcellslocatedinthebottomlayer thestratumbasale oftheskin sepidermis themiddlelayeroftheeye theuvea theinnerear meninges Melaninisapigment色素thatisresponsibleprimarilyforthecolorofskin Nodifferenceinmelanocytenumberbetweenspecies Thedistributionandtyrosinaseactivity Vitiligo Melanoma 黑色素瘤 4 ofalldiagnosedskincancers melanomabeginsinthemelanocytes cellswithintheepidermisthatgiveskinitscolor Melanomahasbeencoined themostlethalformofskincancer becauseitcanrapidlyspreadtothelymphsystemandinternalorgans Withearlydetectionandpropertreatment thecurerateformelanomaisabout95 Onceitsspreads theprognosisispoor Melanomamostoftendevelopsinapre existingmoleorlookslikeanewmole whichiswhyitisimportantforpeopletoknowwhattheirmoleslooklikeandbeabletodetectchangestoexistingmolesandspotnewmoles TheHairSebaceousGlands皮脂腺SweatGlandsTheNails TheAccessaryStructuresoftheSkin Acnevulgaris寻常痤疮普通粉刺 orcysticacne isacommondisease characterizedbyareasofskinwithscaly鳞状的redskin blackheads黑头粉刺andwhiteheads pinheads针头 pimples丘疹 nodules小瘤andpossiblyscarring结疤 Acneaffectsmostlyskinwiththedenset密集populationofsebaceousfollicles皮脂腺 theseareasincludetheface theupperpartofthechest andtheback Severeacneisinflammatory炎症性的 butacnecanalsomanifest显现innoninflammatoryforms 2Thelesions损伤arecausedbychangesinpilosebaceous毛囊皮脂腺units skinstructuresconsistingofahairfollicleanditsassociatedsebaceousgland changesthatrequireandrogen雄性激素stimulation Acneoccursmostcommonlyduringadolescence andoftencontinuesintoadulthood Inadolescence acneisusuallycausedbyanincreaseintestosterone睾丸素 whichpeopleofbothgenders性别accrueduringpuberty青春期 AlopeciaTotalis 全頭脱毛症 Alopeciameanslossofhairfromtheheadorbody baldness Hemidesmosomes HD areverysmallstud orrivet likestructuresontheinnerbasalsurfaceofkeratinocytesintheepidermisofskin Theyaresimilarinformtodesmosomeswhenvisualizedbyelectronmicroscopy Whiledesmosomeslinktwocellstogether hemidesmosomesattachonecelltotheextracellularmatrix Desmosomes细胞桥粒aremolecularcomplexesofcelladhesion黏着蛋白proteinsandlinkingproteinsthatattachthecellsurfaceadhesionproteinstointracellularkeratin角蛋白cytoskeletal细胞支架细胞filaments细丝 Thecelladhesionproteinsofthedesmosome desmoglein桥粒芯蛋白anddesmocollin桥粒胶蛋白 aremembersofthecadherin钙粘蛋白familyofcelladhesionmolecules Theyaretransmembraneproteinsthatbridgethespacebetweenadjacentepithelialcellsbywayofhomophilicbindingoftheirextracellulardomainstootherdesmosomalcadherinsontheadjacentcell Bothhavefiveextracellulardomains andhavecalcium bindingmotifs Age associatedskinchangesincludethinning skinlaxity松弛 fragility脆弱 andwrinkles皱纹 Sun exposedareasdemonstrateadditionalagingchanges includingdyspigmentation prematurewrinkling telangiectasia andactinicelastosis ThesunemitsultravioletradiationintheUVA UVB andUVCbands TheEarth sozonelayerblocks97 99 ofthisUVradiationfrompenetratingthroughtheatmosphere OftheultravioletradiationthatreachestheEarth ssurface 98 7 isUVA Photoaging光老化 UVandmolecularandgeneticchangesUVBrayisconsideredasaprimarymutagenthatcanonlypenetratethroughtheepidermaloroutermostlayeroftheskin resultinginDNAmutations Theepidermallayerdoesnotcontainanybloodvesselsornerveendingsbutmelanocytesandbasalcellsareembeddedinthislayer UponexposuretoUVBrays melanocyteswillproducemelanin apigmentthatgivestheskinitscolortone However UVBwillcausetheformationoffrecklesanddarkspots bothofwhicharesymptomsofphotoaging WithconstantexposuretoUVBrays signsofphotoagingmightappearandprecancerouslesionsorskincancermaydevelop UVAraysareabletopenetratedeeperintotheskinascomparedtoUVBrays Hence inadditiontotheepidermallayer thedermallayerwillalsobedamaged Thedermisisthesecondmajorlayeroftheskinanditcomprisescollagen elastin andextrafibrillarmatrixwhichprovidesstructuralsupporttotheskin However withconstantUVAexposure thesizeofthedermislayerwillbereduced therebycausingtheepidermistostartdroopingoffthebody Duetothepresenceofbloodvesselsinthedermis UVArayscouldleadtodilatedorbrokenbloodvesselsmostcommonlyvisibleonthenoseandcheeks Photoaging telangiectasia pigmentation LaserandPhotonskintreatment Sunscreen SPF ratiooftheminimalerythemadose MED ofsunscreen protectedskinovertheMEDofunprotectedskin CurrentlyavailableproductsofferexcellentprotectionfromUVBand toamorevariableextent fromUVA therefore theregularuseofsunscreensshoul