学科分类
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38 个结果
  • 简介:Thesandfishisalizardhavingtheremarkableabilitytomoveindesertsandinaswimming-likefashion.Themostout-standingadaptationstothismodeoflifearethelowfrictionbehaviourandtheextensiveabrasionresistanceofthesandfishskinagainstsand,outperformingevensteel.Weinvestigatedthetopography,thecompositionandthemechanicalpropertiesofsandfishscales.Theseconsistofglycosylatedkeratinswithhighamountofsulphurbutnohardinorganicmaterial,suchassilicatesorlime.Remarkably,atomicforcemicroscopyshowsanalmostcompleteabsenceofattractiveforcesbetweenthescalesurfaceandasilicontip,suggestingthatthisisresponsiblefortheunusualtribologicalproperties.Theunusualglycosylationofthekeratinswasfoundtobeabsolutelynecessaryforthedescribedphenomenon.Thescalesweredissolvedandreconstitutedonapolymersurfaceresultinginpropertiessimilartotheoriginalscale.Thus,weprovideapathwaytowardsexploitationofthereconstitutedscalematerialforfutureengineeringapplications.

  • 标签: 沙鱼皮 石龙子 摩檫学 角质素 磨损 形态
  • 简介:Thestudyoffrictionalpropertiesofhumanskinisimportantformedicalresearch,skincareproductsandtextileexploi-tation.Inordertoinvestigatetheinfluenceofnormalloadandslidingspeedonthefrictionalpropertiesofskinanditspossiblemechanism,testswerecarriedoutonamulti-specimenfrictiontester.Whenthenormalloadincreasesfrom0.1Nto0.9N,normaldisplacementandthefrictioncoefficientofskinincrease.Thefrictioncoefficientisdependentontheload,indicatingthatbothadhesionanddeformationcontributetothefrictionbehaviour.Thedeformationfrictionwasinterpretedusingtheploughmodeloffriction.Whenslidingspeedincreasesfrom0.5mm·s?1to4mm·s?1,thefrictioncoefficientincreasesand'stick-slip'phenomenaincrease,indicatingthathystereticfrictioncontributestothefriction.Thehystereticfrictionwasin-terpretedusingschematicofenergytranslationduringtherigidsphericalprobeslidingonthesoftskinsurface,whichprovidesanexplanationfortheinfluenceoftheslidingspeedonthefrictionalcharacteristicsoftheskin.

  • 标签: 仿生学 滑行速度 皮肤 摩擦系数
  • 简介:Mosquitoesareexceptionalintheirabilitytopierceintohumanskinwithanaturalultimatepainlessmicroneedle,namedfascicle.HerethestructureoftheAedesalbopictusmosquitofascicleisobtainedusingaScanningElectronMicroscope(SEM),andthewholeprocessofthefascicleinsertingintohumanskinisobservedusingahigh-speedvideoimagingtechnique.Directmeasurementsoftheinsertionforceformosquitofascicletopenetrateintohumanskinarereported.Resultsshowthatthemosquitousesaverylowforce(average18μN)topenetrateintotheskin.Thisforceisatleastthreeordersofmagnitudesmallerthanthereportedlowestinsertionforceforanartificialmicroneedlewithanultrasharptiptoinsertintothehumanskin.Inordertounderstandthepiercingmechanismofmosquitofascicletipintohumanmultilayerskintissue,anumericalsimulationisconductedtoanalyzetheinsertionprocessusinganonlinearfiniteelementmethod.Agoodagreementoccursbetweenthenumericalresultsandtheexperimentalmeasurements.

  • 标签: BIOMIMETIC MICRONEEDLE MOSQUITO FASCICLE mechanics penetration
  • 简介:Nitricoxide(NO)isapleiotropicregulator,criticaltonumerousbiologicalprocesses,includingva-sodilatation,neurotransmissionandmacrophage-mediatedimmunity.Thefamilyofnitricoxidesynthases(NOS)comprisesinducibleNOS(iNOS),endothelialNOS(eNOS),andneuronalNOS(nNOS).Interest-ingly,variousstudieshaveshownthatallthreeisoformscanbeinvolvedinpromotingorinhibitingtheetiologyofcancer.NOSactivityhasbeendetectedintumourcellsofvarioushistogeneticoriginsandhasbeenassociatedwithtumourgrade,proliferationrateandexpressionofimportantsignalingcomponentsassociatedwithcancerdevelopmentsuchastheoestrogenreceptor.ItappearsthathighlevelsofNOSexpression(forexample,generatedbyactivatedmacrophages)maybecytostaticorcytotoxicfortumorcells,whereaslowlevelactivitycanhavetheoppositeeffectandpromotetumourgrowth.Paradoxicallytherefore,NO(andrelatedreactivenitrogenspecies)mayhavebothgenotoxicandangiogenicproperties.IncreasedNO-generationinacellmayselectmutantp53cellsandcontributetotumourangiogenesisbyupregulatingVEGF.Inaddition,NOmaymodulatetumourDNArepairmechanismsbyupregulatingp53,poly(ADP-ribose)polymerase(PARP)andtheDNA-dependentproteinkinase(DNA-PK).Anunderstand-ingatthemolecularleveloftheroleofNOincancerwillhaveprofoundtherapeuticimplicationsforthediagnosisandtreatmentofdisease.

  • 标签: 癌症 一氧化碳 合成酶 表达程度 受体
  • 简介:Duetoconcernsregardingtheoverlappingfiguresinthisreviewthatareidenticaltothosecontainedinareviewarticlethatwehaveco-authoredandpublishedearlier,weretracttheabovepaperwepublishedinCellResearch.Weapologizeforanyconfusionthatmaybecausedbythismatter,althoughwestandbythescientificcontentscontainedintheCellResearchpaper.

  • 标签: 肿瘤 基因治疗 病理机制 临床
  • 简介:在肿瘤开始的癌症干细胞(CSC)的重要性坚定地在白血病被建立了并且最近为许多稳固的肿瘤报导了。然而,特别地关于转移,在多级式的癌症前进的CSC的角色有不定义beenwell。癌症转移要求在远机关播种和specializedCSCs的成功的殖民。正常干细胞和CSC的生物学分享显著类似并且当适用于癌症的学习时,可以有重要含意转移。而且,重叠分子和小径的集合最近被识别了调整干细胞移植和癌症转移。这些分子组成两个都为移植CSC由主要肿瘤和养育的机关微型环境的形成便于转移前壁龛的开始的细胞的相互作用的一个复杂网络。在这评论,我们在这个动态领域里调查了最近的进展并且建议CSC在tumorigenesis和转移在假定一个中央角色的癌症前进的一个统一模型。更好作为变形串联的一个基本部件理解ofCSCs将对变形癌症导致新奇治疗学的策略。

  • 标签: 癌细胞 干细胞 细胞转移 肿瘤 器官
  • 简介:基因治疗为癌症的治疗提供一条新途径。编码immunostimulatorycytokines的基因的转移与显著成功被使用了在动物消除癌症。然而,在有这策略的病人的临床的试用限制了功效。因此,基因转移向量系统的改进是必要的。混合病毒的向量,与鼠科的IL-12或记者LacZ基因由SFVreplicon组成,被构造。这混合向量在vitro并且在vivo在HCC显示出表示的特性和高水平。在一个老鼠orthotropic肝肿瘤模型,没有伴随毒性,由有mIL-12基因的混合向量的确定的肿瘤的治疗导致了一项强壮的反肿瘤活动。随后,助手依赖者侵入人体气管粘膜的病菌包含mifepristone(RU486)的向量可诱导的系统被构造为控制并且人的interleukin的肝特定的表示12(hIL-12)(HD-Ad/RUhIL-12)并且鼠标IL-12(mIL-12)(HD-Ad/RUmIL-12)。数据证明hIL-12的高、支撑的浆液层次能被继续RU486的管理达到每12或24h。hIL-12的重复正式就职能被获得在上,至少在HD-Ad/RUhIL-12的单个注射以后的48个星期的一个时期。肝转移与的处理HD-Ad/RUmIL-12,正RU846在所有动物导致了完全的肿瘤回归。然后,不同cytokine基因被插入到有条件的replicative侵入人体气管粘膜的病菌向量(也叫的oncolytic侵入人体气管粘膜的病菌)。在肿瘤房间的侵入人体气管粘膜的病菌的复制将杀死肿瘤房间和版本病毒,它感染包围肿瘤房间。由oncolytic侵入人体气管粘膜的病菌的cytopathic效果和transgene的生物效果的联合将施加强壮的反肿瘤活动。向量的这些新类型可以为癌症基因治疗提供一个有势力和安全工具。

  • 标签: 癌症 腺病毒 细胞活素 基因治疗
  • 简介:Ourpreviousreportshaveshownthatlamininglycopeptides(LN-GPs),thetotalglycopeptidespreparedfromlaminin(LN),canpreventtheexperimentallungmetastasisandlivermetastasisofmousecancercells.Inordertoexploretheanti-metastaticmechanismofLN-GPs,westudiedtheeffectsofLN-GPsonmetastasisrelatedbehaviorsofcancercellsinvitro.LN-GPsdidnotaffectcellsurvival.However,LN-GPsinhibitedcellattachmentandspreadingofS180cellsonLN-andMatrigelsubstrateindose-dependentandtime-dependentmanners.Moreover,inhibitionofcellattachmentandspreadingonMatrigelsubstratesweremuchgreateronMatrigelsubstratethanonLNsubstrate.InthegresenceofLN-GPs,S180cellsonLNsubstratechangedfromaflattenedpolygonalshapetoaroundone,themigrationofS180cellsonLNsubstratedecreased,andthenumberofahighlyinvasivehumanpulmonarygiantcarcinomaPGcellsinvadingMatrigelfilterinaBoydenchamberwasreduced.LN-GPsthushavemultipleinhibitoryeffectsoncancermetastasisrelatedbehaviors.

  • 标签: LAMININ 癌细胞转移 相关行为 非胶原糖蛋白 LN-GP
  • 简介:MicroRNAs(miRNAs)内长的、小、非编码的RNA,它能够在post-transcriptional的silencing基因表示铺平。在这研究,我们报导miR-205是显著地在与匹配的正常的胸织物相比的胸肿瘤的underexpressed。同样,包括MCF-7和MDA-MB-231,乳癌房间行比非恶意的MCF-10A房间表示低级miR-205。兴趣,miR-205的宫外的表示显著地禁止房间增长和抛锚独立人士生长,以及房间侵略。而且,miR-205被显示在一个动物模型压制肺转移。最后,西方的污点与试金表明的酶记者结合了那ErbB3和脉管的endothelial生长因素A(VEGF--一)是为miR-205的直接目标,并且这miR-205-mediated抑制通过和在ErbB3和VEGF的3鈥?untranslated区域(3鈥?UTR)的通常认为的miR-205绑定地点的直接相互作用是可能的--一。一起,这些结果建议miR-205是在乳癌的肿瘤suppressor。

  • 标签: 细胞生长 乳腺癌 血管内皮生长因子 入侵 microRNA 转录后水平
  • 简介:Protein-proteininteractions(PPIs)havebeenwidelystudiedtounderstandthebiologicalprocessesormolecularfunctionsassociatedwithdifferentdiseasesystemslikecancer.Whilefocusedstudiesonindividualcancershavegeneratedvaluableinformation,globalandcomparativeanalysisofdatasetsfromdifferentcancertypeshasnotbeendone.Inthiswork,wecarriedoutbioinformaticanalysisofPPIscorrespondingtodifferentiallyexpressedgenesfrommicroarraysofvarioustumortissues(belongingtobladder,colon,kidneyandthyroidcancers)andcomparedtheirassociatedbiologicalprocessesandmolecularfunctions(basedonGeneOntologyterms).Weidentifiedasetofprocessesorfunctionsthatarecommontoallthesecancers,aswellasthosethatarespecifictoonlyoneorpartialcancertypes.Similarly,proteininteractionnetworksinnucleicacidmetabolismwerecomparedtoidentifythecommon/specificclustersofproteinsacrossdifferentcancertypes.Ourresultsprovideabasisforfurtherexperimentalinvestigationstostudyproteininteractionnetworksassociatedwithcancer.Themethodologydevelopedinthisworkcanalsobeappliedtostudysimilardiseasesystems.

  • 标签: 蛋白质相互作用 相关基因 癌症 差异表达基因 价格指数 生物过程
  • 简介:组蛋白deacetylases(HDAC)并且嘘一乙酰转移ases(帽子)是其酶的活动控制蛋白质离氨酸残余的乙酰化状态的二抵抗酶家庭,尤其是在核心histones.Acetylation的N终端扩展包含的那些嘘通过它对染色质符合构造的影响影响基因表示。Inaddition,几non-histone蛋白质由特定的离氨酸残余的乙酰化状态在他们的稳定性或生物功能被调整。HDAC在大量的生物学过程干涉并且是部分一多每个成员在有它的专业化功能的蛋白质家庭。另外,HDAC活动紧通过指向的招募,protein-proteininteractions和translational以后修正被控制。房间周期前进,房间幸存和区别的控制在这些酶的最重要的角色之中。因为这些过程被恶意的转变影响,HDAC禁止者作为反被开发在癌症病人的肿瘤的药和areshowing鼓励功效。

  • 标签: 组蛋白脱乙酰酶 脱乙酰作用 组蛋白乙酰转移酶 基因转录 分子生物学 癌症
  • 简介:Overthepastdecades,cellsurfacecharge,althoughexperimentallyobserved,hasnotbeenwellunderstoodparticularlyfromtheviewpointofbiophysics.Ourrecentstudieshaveshownthatallcancercellsexhib让negativesurfacechargesthataredirectlyproportionaltothesecretedlacticacid,auniquecancermetaboliccharacteristic:highrateofglycolysis.Wehavethereforedesignedanddevelopedasetofelectrically-charged,fluorescent,andsuper-paramagneticnanoprobes,capableofsensitivedetectionofcancercellsbasedonthesurfacecharges.Theseprobesareutilizedtobindontocellsviaelectrostaticreactionforcaptureandmagneticseparation.Inthisfashion,weareabletocharacterizecellsurfacechargesthatareregulatedbydifferentmetabolicpatterns,thereforeeffectivelydistinguishingthecancercellsfromthenormalcells.All22cancercellsofdifferentorgansarefoundtobenegativelychargedthereforeboundstronglybythepositively-chargednanoprobes,whereasthenormalcellsshowinsignificantbindingtothenanoprobesofeitherchargesigns(positiveornegative).Thisfindingsuggeststhatalltestedcancercellsarenegatively-chargedandnormalcellsareeithercharge-neutralorslightlypositive.Fordiagnosis,cancercellscanbedetected,electrostaticallybound,andmagneticallyseparatedinbloodbychargedandsuper-paramagneticnanoprobes.Intherapeutics,circulatingcancercells(CTCs)canbefilteredandremovedinacontinuousfashiontoreducetheriskofcancermetastasis.Ifsuccessful,thisnewnanotechnologywillrevolutionizeearlycancerdiagnosisandpotentiallyenablenewtherapeuticsinclinicalsettings.

  • 标签: NANOTECHNOLOGY Cancer CELL CELL SURFACE charge
  • 简介:Arraycomparativegenomichybridization(CGH)hasbeenpopularlyusedforanalyzingDNAcopynumbervariationsindiseaseslikecancer.Inthisstudy,weinvestigated82sporadicsamplesfrom49breastcancerpatientsusing1-MbresolutionbacterialartificialchromosomeCGHarrays.Anumberofhighlyfrequentgenomicaberrationswerediscovered,whichmayactas'drivers'oftumorprogression.Meanwhile,thegenomicprofilesoffour'normal'breasttissuesamplestakenatleast2cmawayfromtheprimarytumorsiteswerealsofoundtohavesomegenomicaberrationsthatrecurredwithhighfrequencyintheprimarytumors,whichmayhaveimportantimplicationsforclinicaltherapy.Additionally,weperformedclasscomparisonandclasspredictionforvariousclinicopathologicalparameters,andalistofcharacteristicgenomicaberrationsassociatedwithdifferentclinicopathologicalphenotypeswascompiled.Ourstudyprovidescluesforfurtherinvestigationsoftheunderlyingmechanismsofbreastcarcinogenesis.

  • 标签: 比较基因组杂交 乳腺癌 拷贝数 DNA 阵列 畸变
  • 简介:二维的polyacrylamide胶化电气泳动(2D页)并且帮助矩阵的激光解吸附作用/电离双人脚踏车time-of-flight团spectrometry(MALDI-TOF/TOF-MS),与联机数据库寻找合并了,被执行调查乳癌和邻近的正常的微分蛋白质胸纸巾。考虑到那浆液白朊富有地在正常被介绍,控制样品,从12在11检测的15个微分点(91.7%)乳癌样品被联机SIENA-2DPAGE数据库寻找和MALDI-TOF/TOF-MS分析识别。结果显示乳癌的病理学的变化涉及物质新陈代谢的扩大,解朊的活动的提升,酶的一些禁止者的活动的衰落等等。与改变的表示涉及乳癌的病理学的进程的一些重要蛋白质可以是有用简历标记,例如alpha-1-antitrypsin,EF-1-beta,组织蛋白酶D,TCTP,SMT3A,RPS12,和PSMA1,SMT3A,RPS12,和PSMA1首先在这研究为乳癌在之中被报导。

  • 标签: 乳腺癌 生物标志物 分子机构 乳腺组织
  • 简介:Inthisstudy,wepresentaconstructivealgorithmfortrainingcooperativesupportvectormachineensembles(CSVMEs).CSVMEcombinesensemblearchitecturedesignwithcooperativetrainingforindividualSVMsinensembles.Unlikemostpreviousstudiesontrainingensembles,CSVMEputsemphasisonbothaccuracyandcollaborationamongindividualSVMsinanensemble.AgroupofSVMsselectedonthebasisofrecursiveclassifiereliminationisusedinCSVME,andthenumberoftheindividualSVMsselectedtoconstructCSVMEisdeterminedby10-foldcross-validation.ThiskindofSVMEhasbeentestedontwoovariancancerdatasetspreviouslyobtainedbyproteomicmassspectrometry.BycombiningseveralindividualSVMs,theproposedmethodachievesbetterperformancethantheSVMEofallbaseSVMs.

  • 标签: 肿瘤识别 计算方法 生物学性能 蛋白质