简介：Thisreviewbeginswithabriefcommentaryonthediversityofplacentationmechanisms,andthengoesontoexaminetheextensivealterationswhichoccurintheplasmamembraneofuterineepithelialcellsduringearlypregnancyacrossspecies.Ultrastructural,biochemicalandmoregeneralmorphologicaldatarevealthatstrikinglycommonphenomenaoccurinthisplasmamembraneduringearlypregnancydespitethediversityofplacentaltypes-fromepitheliochorialtohemochorial,whichultimatelyformindifferentspecies.Toencapsulatetheconceptthatcommonmorphologicalandmolecularalterationsoccuracrossspecies,thattheyarefoundbasolaterallyaswellasapically,andthatmoreovertheyareanongoingprocessduringmuchofearlypregnancy,notjustaneventatthetimeattachment,braneduringearlypregnancyarekeytouterinereceptivity.

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简介：MedicalforgedCoCrMoalloywastreatedbyplasmanitridingprocess.Themicrostructureswerecharacterizedby3Dprofiler,SEMandXRD.Thetribologicalpropertieswereinvestigatedunderlubricationof25%bovineserumsolution.Resultsshowthatplasmanitridingisapromisingprocesstoproducethick,hard,andmorewearresistantlayersonthesurfaceofCoCrMoalloy.AllnitridedsamplesshowedanimportantincreaseinthesurfacehardnessduetotheformationofharderCrNandCr2Nphaseswithcompactnano-crystallinestructures.ThetypicalhardnessvaluesofHV0.05increasedalmosttwotimesthanuntreatedone.Underbovineserumlubrication,atlownitridingtemperaturetheCoefficientofFriction（COF）ofnitridedsamplewaslowerthanthatofuntreatedsample,butathighnitridingtemperaturetheCOFwasalmostthesameastheuntreatedone.Comparedwiththeuntreatedsample,thenitridedsamplesshowedlowerwearratesandhigherwearresistanceunderdifferentnitridingtemperatures.TheadhesivewearisthemainmechanismforuntreatedCoCrMoalloyandthewearmechanismsofnitridedonesarethefatiguewearandslightadhesivewear.ItisconcludedthattheimprovementofwearresistanceisascribedtothehardnitrideformationofCrNandCr2Nphasesatthenitridedsurfaces.

简介：ThispaperreportstheadsorptionofBovineSerumAlbumin(BSA)ontoDielectricBarrierDischarge(DBD)processedPoly(methylmethacrylate)(PMMA)surfacesbyaQuartzCrystalMicrobalancewithDissipationmonitoring(QCM-D)tech-nique.ThepurposeistostudytheinfluenceofDBDprocessingonthenatureandscaleofBSAadsorptiononPMMAsurfaceinvitro.ItwasobservedthatDBDprocessingimprovesthesurfacewettabilityofPMMAfilm,afactattributabletothechangesinsurfacechemistryandtopography.ExposureofthePMMAtoPhosphateBuffedSaline(PBS)solutionintheQCM-Dsystemresultedinsurfaceadsorptionwhichreachesanequilibriumafterabout30minutesforpristinePMMA,and90minutesforprocessedPMMAsurface.SubsequentinjectionofBSAinPBSindicatedthattheproteinisimmediatelyadsorbedontothePMMAsurface.ItwasrevealedthatadsorptionbehaviourofBSAonpristinePMMAdiffersfromthatonprocessedPMMAsurface.AsloweradsorptionkineticswasobservedforpristinePMMAsurface,whilstaquickadsorptionkineticsforprocessedPMMA.Moreover,thedissipationshiftofproteinadsorptionsuggestedthatBSAformsamorerigidstructureonpristinePMMAsurfacethatonprocessedsurface.ThesedatasuggestthatchangesinwettabilityandattendantchemicalpropertiesandsurfacetextureofthePMMAsurfacemayplayasignificantroleinBSAadsorptionprocess.

简介：Theplasmamembrane(PM)isacomplexenvironmentconsistingof>700speciesoflipidsandmanydifferenttypesofmembrane-associatingproteins.Theselipidsandmembraneproteinsaredistributedheterogeneouslyintonanometer-sizeddomains,callednanoclusters.ThelateralspatialsegregationinthePMgivesrisetodifferentcurvatureandlipidcomposition,whichdeterminestheefficiencyofeffectorbindingandsignaltransmission.Here,wedescribeanelectronmicroscopy(EM)-spatialmappingtechniquetoquantifytheextentofnanoclustersformationinthePM.Thenano-assembliesinthePMarequantifiedviaexpressingtheGFP-taggedproteinsorlipid-bindingdomainsinthecells,whicharethenimmunolabeledwiththegoldnanoparticlespre-coupledtotheanti-GFPantibody.ThegoldnanoparticlesarevisualizedviathetransmissionEMathighmagnification.ThestatisticalanalysisoftheRipley'sK-functioncalculatesthespatialdistributionofthegoldnanoparticles.Importantspatialparameters,suchastheextentofnanoclustering,theclusteredfraction,thenumberofproteinspercluster,theoptimalsizeofananocluster,andthenumberofproteinslocalizedtothePM,canbecalculated.Furtherdetailedaggregationpattern,suchasthepopulationsofmonomers,dimers,trimers,andhigherorderedoligomers,canalsobeextractedfromthespatialanalysis.TheEM-bivariateanalysisquantifiestheextentofco-localizationbetweentwodifferentcomponentsinthePMandprovideskeyinformationontheprotein-proteinandtheprotein-lipidinteractionsoveralong-distancescalefrom8to240nm.

简介：Plasmamembrane(PM)Ca^2+-ATPaseactivityinpoplarapicalbudmeristematiccellsduringshort-day(SD)-induceddormancydevelopmentwasexaminedbyaceriumprecipitationEM-cytochemicalmethod.Ca^2+-ATPaseactivity,indicatedbythestatusofceriumphosphateprecipitatedgrains,waslocalizedmainlyontheinteriorface(cytoplasmicside)ofthePMwhenplantsweregrownunderlongdaysandreachedadeepdormancy.Afewreactionproductswerealsoobservedonthenuclearenvelope.Whenplantbudsweredevelopingdormancyafter28to42dofSDexposure,almostnoreactionproductswerepresentontheinteriorfaceofthePM.Incontrast,alargenumberofceriumphosphateprecipitatedgrainsweredistributedontheexteriorfaceofthePM.After70dofSDexposure,whenbudshaddevelopedadeepdormancy,thereactionproductsofCa^2+-ATPaseactivityagainappearedontheinteriorfaceofthePM.TheresultsseemedsuggestingthattwokindsofCa^2+-ATPasesmaybepresentonthePMduringtheSD-induceddormancyinpoplar.OneistheCa^2+-pumpingATPase,whichislocatedontheinteriorfaceofthePM,formaintainingandrestoringtheCa^2+homeostasis.Theothermightbeandecto-Ca^2+-ATPase,whichislocatedontheexteriorfaceofthePM,fortheexocytosisofcellwallmaterialsassuggestedbythefactofthecellwallthickeningduringthedormancydevelopmentinpoplar.