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481 个结果
  • 简介:BACKGROUND:Recentstudieshaveindicatedthatblood-brainbarrier(BBB)disruptionfollowingsu-barachnoidhemorrhage(SAH)significantlycorrelateswiththedevelopmentofbraininjuryandpoorprognosisofpatientssubjectedtoSAH.OBJECTIVE:ToinvestigatebothfunctionalandstructuralchangesrelatedtoBBBinvariousphasesafterSAHinratsthroughquantitativeandqualitativemethods.DESIGN,TIMEANDSETTING:Thisexperiment,acompletelyrandomizeddesignandcontrolledex-periment,wasperformedattheDepartmentofNeurosurgery,theSecondAffiliatedHospitalofChongqingUniversityofMedicalSciencesfromJune2006toMarch2007.MATERIALS:Atotalof128female,healthy,Sprague-Dawleyratswereselectedforthisstudy.Mainreagentsandinstruments:EvansBluedye(SigmaCompany,USA),fluorescencespectrophotometer(ShimadzuCompany,Japan),andtransmissionelectronmicroscope(OlympusCompany,Japan).METHODS:Theincluded128ratswererandomlydividedintotwogroups:sham-operatedgroup(n=16)andSAHgroup(n=112).RatsintheSAHgroupweredividedintosevensubgroups:6,12,24,36,48,60,and72hoursafterSAH(16ratsforeachtimepoint).ExperimentalSAHwasinducedbybloodinjectionintothepre-chiasmaticcistern(300μL).Thesham-operatedgroupreceivedanequivalentvolumeofnormalsalinesolution(300μL)injectedintothesubarachnoidspace.MAINOUTCOMEMEASURES:Braintissuewatercontentwasdeterminedbythewet-drymethod.BBBpermeabilityinthecerebralcortexwasdeterminedbyEvansBluedyeandfluorescentspectrophotometer.TheultrastructuralchangesinBBBwereobservedwithtransmissionelectronmicroscope.RESULTS:Comparedwiththesham-operatedgroup,SAHinducedasignificantincreaseinbrainwatercontentbetween24and60hours(F=888.32,P<0.05).Brainwatercontentincreasedtoamaximumby36hoursafterSAH,normalizingby72hours.EvansBluecontentinthecerebralcortexofSAHgroupratsbegantoincreaseby24hoursafterSAH,pea

  • 标签: 珠网膜下出血 血脑屏障 小鼠 动物实验
  • 简介:Purpose:Thepurposeofthisstudywastoinvestigatetheeffectsofobesityandhigh-intensityacuteexerciseonoxidant-antioxidantstatus,neurotrophicfactorexpression,andblood-brainbarrier(BBB)disruption.Methods:Twenty-fourhealthy,untrainedmen(12non-obese(mean14.9%bodyfat)and12obesesubjects(mean29.8%bodyfat))performed20minofcontinuoussubmaximalaerobicexerciseat85%maximaloxygenconsumption.Bloodsamplingwasperformedtoexaminetheoxidant-antioxidantstatus(reactiveoxygenspecies(ROS)andsuperoxidedismutase(SOD)),neurotrophicfactors(brain-derivedneurotrophicfactor(BDNF)andnervegrowthfactor(NGF)),andBBBdisruption(S100βandneuron-specificenolase)beforeandafteracuteexercise.Results:Theobesegroupshowedsignificantlyhigherpre-exerciseserumROSlevelsandsignificantlylowerpre-exerciseserumSODlevelsthanthenon-obesegroup(p<0.05).SerumROS,SOD,BDNF,NGF,andS100βlevelsweresignificantlyincreasedpost-exercisecomparedwithpre-exerciselevelsinboththenon-obeseandtheobesegroups(p<0.05).TheobesegroupshowedsignificantlyhigherserumROS,BDNF,NGF,andS100βlevelspost-exercisecomparedtothenon-obesegroup(p<0.05).Conclusion:OurstudysuggeststhatepisodicvigorousexercisecanincreaseoxidativestressandbloodneurotrophicfactorlevelsandinducedisruptionoftheBBB.Moreover,highlevelsofneurotrophicfactorinthebloodafterexerciseintheobesegroupmaybeduetoBBBdisruption,anditisassumedthatoxidativestresswasthemaincauseofthisBBBdisruption.

  • 标签: 水平运动 血脑屏障 氧化应激 高强度 脑源性神经营养因子 肥胖
  • 简介:AbstractObjective:Glioma is the most common and aggressive primary brain tumor. Here, we aimed to establish a nano-drug carrier system to traverse the blood-brain barrier for the treatment and inhibition of glioma migration.Methods:The synthesis of bovine serum albumin protected-silver nanoclusters (BSA-AgNCs) was performed using chemical reduction. The drug paclitaxel (PTX) can be loaded into BSA-AgNCs through electrostatic and hydrophobic interactions to formulate spherical BSA-AgNC-PTX nanoparticles (BSA-AgNC-PTX NPs). A glioma mouse model was established by injecting U251-GFP-Luc cells into the mouse striatum, and all surgical procedures were approved by the Animal Ethics Committee of Nanchang University (SYXK2019-0003) on December 29, 2019.Results:The BSA-AgNC-PTX NPs were able to efficiently pass through the blood-brain barrier, both in vitro and in vivo, to deliver the drug to the tumor site. The in vivo assessment of BSA-AgNC-PTX NPs in glioblastoma multiforme-bearing mice revealed the significant inhibition of tumor growth and migration, prolonging the survival of the mice.Conclusion:These results indicated that BSA-AgNCs might represent an ideal nanocarrier for the treatment of glioma and has the potential to be used in the treatment of a variety of central nervous system diseases.

  • 标签: blood-brain barrier glioma paclitaxel renal clearable silver nanoclusters
  • 简介:BACKGROUND:Theintegrityofthebloodbrainbarrier(BBB)playsanimportantroleinthepatho-physiologicalprocessofcerebralischemia/reperfusioninjury.Ithasbeenrecentlyobservedthatmetalloproteinase-9(MMP-9)iscloselyrelatedtocerebralischemia/reperfusioninjuryOBJECTIVE:ThisstudywasdesignedtoobserveMMP-9expressionintheratbrainaftercerebralischemia/reperfusioninjuryandtoinvestigateitscorrelationtoBBBpermeability.DESIGN,TIMEANDSETTING:Thisstudy,arandomizedcontrolledanimalexperiment,wasperformedattheInstituteofNeurobiology,CentralSouthUniversitybetweenSeptember2005andMarch2006.MATERIALS:NinetyhealthymaleSDrats,aged3–4months,weighing200–280g,wereusedinthepresentstudy.Rabbitanti-ratMMP-9polyclonalantibody(Boster,Wuhan,China)andEvansblue(Sigma,USA)werealsoused.METHODS:Allratswererandomlydividedinto9groupswith10ratsineachgroup:normalcontrolgroup,sham-operatedgroup,andischemiafor2hoursfollowedbyreperfusionfor3,6,12hours,1,2,4and7daysgroups.Intheischemia/reperfusiongroups,ratsweresubjectedtoischemia/reperfusioninjurybysutureocclusionoftherightmiddlecerebralartery.Inthesham-operatedgroup,ratsweremerelysubjectedtovesseldissociation.Inthenormalcontrolgroup,ratswerenotmodeled.MAINOUTCOMEMEASURES:BBBpermeabilitywasassessedbydeterminingthelevelofeffusionofEvansblue.MMP-9expressionwasdetectedbyanimmunohistochemicalmethod.RESULTS:All90ratswereincludedinthefinalanalysis.BBBpermeabilityalterationwascloselycorrelatedtoischemia/reperfusiontime.BBBpermeabilitybegantoincreaseatischemia/reperfusionfor3hours,thenitgraduallyreachedapeaklevelatischemia/reperfusionfor1day,andthereafteritgraduallydecreased.MMP-9expressionbegantoincreaseatischemia/reperfusionfor3hours,thengraduallyreacheditspeaklevel2daysafterperfusion,andthereafteritgraduallydecreased.CONCLUSION:

  • 标签: 大脑 再灌注损伤 血液 分析方法
  • 简介:Withaself-madenear-infraredanalyticalinstrumenttobloodandoxygenparametersinhumanbrain,80casesinwhich20arehealthypersonsand30areanaesthetisedcasesandothersarepatientswithheartfunctionlackistakentoexamine,andthedataofbloodandoxygeninbraintissuewerecollectedandanalyzedbythemethodofpowerspectrumandcorrelationfunction.Theresultsindicatethat:(1)Theaveragebrainoxygensaturationofhealthypersonsandanaesthetisedcasesisabout80%,inaccordwithnormalparameterofphysiology.Contrastively,theaveragebrainoxygensaturationofpatientswithheartfunctionlackis72.8%,whichisobviouslylessthanthatofhealthypersonsandanaesthetisedcases.Theprobabilityofmedicalstatisticsislessthan0.01.(2)Theshapesofwaveofbrainbloodandoxygenforthehealthypersonandtheanaesthetisedcaserevealsmallperiodicalfluctuationswithstableshapeandbaseline,andthetrendofincreaseordecreaseofbloodandoxygenparametersinbraintissueissynchronousandaphasereversal,butforthepatientwithheartfunctionlackinabrainoxygenlackstate,theshapesofwaveareirregular.Thisisahintthatnearinfraredlightpassingthroughtissuecanreflecttheintuitionisticchangeofbrainbloodandoxygenparameters.(3)Thepowerspectraofbrainbloodandoxygenforthehealthypersonandtheanaesthetisedcasehasaclearmainpeak,narrowbandwidthandperfectsuperpositioneachother,butthepowerspectraforthepatientwithheartfunctionlackinabrainoxygenlackstateisonthecontrary.(4)Theaveragecrosscorrelationcoefficientofbrainbloodandoxygenforhealthypersonsandanaesthetisedcasesis-0.9825±0.1027closeto-1.Buttheaveragecrosscorrelationcoefficientforpatientswithheartfunctionlackinabrainoxygenlackstateismerely-0.8923±0.1035whichisobviouslygreaterthan-1andtheprobabilityofmedicalstatisticsislessthan0.01.Theclinicexperimentshaveprovedthattheshapes

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  • 简介:AbstractClinical ophthalmologists consider each retinal disease as a completely unique entity. However, various retinal diseases, such as uveitis, age-related macular degeneration, diabetic retinopathy, and primary open-angle glaucoma, share a number of common pathogenetic pathways. Whether a retinal disease initiates from direct injury to the blood-retinal barrier (BRB) or a defect/injury to retinal neurons or glia that impairs the BRB secondarily, the BRB is a pivotal point in determining the prognosis as self-limiting and recovering, or developing and progressing to a clinical phenotype. The present review summarizes our current knowledge on the physiology and cellular and molecular pathology of the BRB, which underlies its pivotal role in the initiation and development of common retinal diseases.

  • 标签: Blood-retinal barrier Retinal inflammatory diseases Age-related macular degeneration Diabetic retinopathy Primary open-angle glaucoma Neuroinflammation
  • 简介:Freeradicalsinducedbytraumaticbraininjuryhavedeleteriouseffectsonthefunctionandantioxidantvitaminlevelsofseveralorgansystemsincludingthebrain.Melatoninpossessesantioxidanteffectonthebrainbymaintainingantioxidantenzymeandvitaminlevels.Weinvestigatedtheeffectsofmelatoninonantioxidantabilityinthecerebralcortexandbloodoftraumaticbraininjuryrats.Resultsshowedthatthecerebralcortexβ-carotene,vitaminC,vitaminE,reducedglutathione,anderythrocytereducedglutathionelevels,andplasmavitaminClevelweredecreasedbytraumaticbraininjurywhereastheywereincreasedfollowingmelatonintreatment.Inconclusion,melatoninseemstohaveprotectiveeffectsontraumaticbraininjury-inducedcerebralcortexandbloodtoxicitybyinhibitingfreeradicalformationandsupportingantioxidantvitaminredoxsystem.

  • 标签: 创伤性脑损伤 大脑皮层 褪黑激素 氧化应激 大鼠 还原型谷胱甘肽
  • 简介:FromApril1995toOctober1999,135patientswithconcussionofbrainwereexaminedwiththreedimensionaltranscranialDoppler(3D-TCD)andthechangeofcerebralbloodflowinvariousphaseswasanalyzedtoevaluatetheeffectof3D-TCDondiagnosisandtherapyofbrainconcussion.

  • 标签: 脑血流 脑震荡 三维-多普勒超声 影像学诊断 临床意义
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  • 作者: Jensen Eva Johanne Leknes Nohr Ellen Aagaard Scholbach Thomas Eggebø Torbjørn Moe
  • 学科: 医药卫生 >
  • 创建时间:2020-08-10
  • 出处:《母胎医学杂志(英文)》 2020年第03期
  • 机构:National Center for Fetal Medicine, St. Olavs Hospital, Trondheim University Hospital, Trondheim 7030, Norway,Research Unit for Gynecology and Obstetrics, Institute of Clinical Research, University of Southern Denmark, Odense 5000, Denmark; Centre for Women’s, Family and Child Health, University of South-Eastern Norway, Kongsberg 3603, Norway,Ultrasound Institute, Leipzig 04229, Germany,National Center for Fetal Medicine, St. Olavs Hospital, Trondheim University Hospital, Trondheim 7030, Norway; Institute of Clinical and Molecular Medicine, Norwegian University of Science and Technology, Trondheim 7030, Norway; Department of Obstetrics and Gynecology, Stavanger University Hospital, Stavanger 4019, Norway
  • 简介:AbstractObjective:This article aimed to compare the peripheral blood flow intensity (BFI) in the maternal right and left kidney in uncomplicated third trimester pregnancies and to study possible associations between parenchymal BFI in the kidneys and maternal, labor and new-born characteristics.Methods:We conducted a prospective cohort study in third trimester pregnancies at Trondheim University Hospital, Norway, from January to April 2018. The BFI in the maternal kidneys was examined with color Doppler ultrasound and the peripheral BFI was calculated using the Pixel Flux-method which is a method based on pixel wise calculation of color in an image. Velocity was coded by the color bar in the ultrasound device. The peripheral BFI was calculated as the product of velocity and area encoded by all colored pixels divided by all pixels within the cortical layer by a software examining the color in each pixel of a standardized region of interest of the renal parenchyma in video-clips through a complete heart cycle. BFI (cm/s) was thus calculated as follows:The primary outcome measure was peripheral BFI in the renal cortex. We also examined associations between BFI in the entire cortex with maternal age, body mass index, blood pressure, pH in the umbilical artery, Apgar score after 5 minutes and birthweight.Results:In all, 51 pregnant women were included in the study, but 17 were excluded, mainly due to movement artifacts from the pulsating aorta, leaving 34 women in the final study population. We found significantly lower BFI in the cortex of the left kidney compared with the right kidney, 0.37 cm/s versus 0.69 cm/s, respectively (P = 0.04). Dividing into regions, the BFI was significantly lower in the proximal 25% of the left renal cortex compared to the corresponding right side (P= 0.01), and in the proximal 50% cortex (P= 0.02), but the differences were not significantly different in the distal 25% (P= 0.06) or in the distal 50% (P= 0.20) of the renal cortex.We observed a significant negative correlation between peripheral BFI in the left kidney and both systolic blood pressure (r = -0.38; P= 0.03) and diastolic blood pressure (r= -0.36; P= 0.04), and no significant correlations between BFI with maternal age, body mass index, blood pressure, pH in the umbilical artery, Apgar score after 5 minutes and birthweight in the left kidney (P > 0.05). We did not observe any significant correlations between BFI in the right kidney and maternal or new-born characteristics (P > 0.05).Conclusion:The BFI in the left renal cortex was lower compared with the right renal cortex, and BFI in the left renal cortex was negatively correlated with blood pressure, but not significantly correlated with maternal age, body mass index or newborn characteristics. We did not observe any significant correlations between BFI in the right kidney and maternal or new-born characteristics.

  • 标签: Ultrasonography Doppler Pregnancy Renal blood flow Pre-eclampsia Pixel Flux method
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  • 简介:BACKGROUND:Highincidenceofstrokeatinterchangeperiodofautumnandwinterwasdemonstratedbyepidemiologicalsurvey,andthespecificcausesshouldbefurtherinvestigated.OBJECTIVE:Toinvestigatetheinfluenceofartificialcoldexposureontheincidenceofstrokeinrenovascularhypertensiverats(RHR),andanalyzetheassociationwithbloodpressureandcold-inducibleRNAbindingprotein(CIRP)mRNAexpressioninbraintissue.DESIGN:Acompletelyrandomizedgroupingdesign,arandomizedcontrolanimaltrial.SETTINGS:LabofNeurology,theFirstAffiliatedHospitalofSunYat-senUniversity;DepartmentofChemistry,OpenlaboratoryofChemicalBiology,InstituteofMolecularTechnologyforDrugDiscoveryandSynthesis,UniversityofHongKong.MATERIALS:MaleSDrats(n=460),weighing80-100gwereobtainedfromGuangdongProvinceHealthAnimalUnit.AmodifiedRXZ-300Aintelligentartificialclimatecabinet(NingboJiangnanInstrumentCo.,Ltd.,China).METHODS:TheexperimentwereprocessedintheLabofNeurology,theFirstAffiliatedHospitalofSunYat-senUniversityandtheOpenLaboratoryofChemicalBiology,InstituteofMolecularTechnologyforDrugDiscoveryandSynthesis,UniversityofHongKongfromOctober2004toNovember2005.Rats(n=400)wereoperatedtoestablish2-kidney2-clipRHRmodelasdescribedpreviously.Thesham-operatedrats(n=60)servedasnormotensivecontrols.Eightweekslater,300ofRHRwererandomlyselectedaccordingtotheirsystolicbloodpressure(SBP)anddividedinto3sub-groups(n=100pergroup):mildhypertensivegroup(SBPof160-200mmHg),moderatehypertensivegroup(SBPof200-220mmHg)andseverehypertensivegroup(SBP>220mmHg).Eachgroupwasfurtherdividedintotwogroups(n=50)underACEandnon-ACE.Normalsham-operatedSDrats(n=60),SBP<140mmHg,wererandomlydividedintotwogroups:Sham-operatedcontrolgroup(n=30)underACEandnon-ACE.ToestablishtheACEandnon-ACEtreatment,ratswerehousedindividuallyinartifici

  • 标签: 高血压 人工冷曝光 肾血管高血压 蛋白质
  • 简介:Ultrasonicbiophysicistsandphysicianshavecontinuouslyexhibitedgreatinterestinstudyingtheultrasonicpropertiesofblood.Itisshownthatcompressibilityofredcellappearstobeinverselypropor-tionalwithitshemoglobincontent.Amongultrasonicattenuationproducedbyredcellstructurelevelinblood,absorptionofredcellplayspredominantrole,viscousrelativemotionlossaccountsforlessthan15%,andcellscatteringcontributionisnegligible.Thecoagulationprocessofbloodisaccompaniedbysignificantchangeofsoundparameters.Themarkedadvantagehasbeenfoundintestofbloodcoagula-tionprocessbyusingultrasonictechniquethanthetraditionalviscousmethod.Bloodcoagulationcausessoundattenuation,soundbackscatteringandnonlinearityparameterB/Atoincrease,buttheattenuationfrequencydependencehardlychanges.Allofthesefindingsareofanimportantrealisticsignifi-cancefordevelopingultrasonicmedicine.

  • 标签: COAGULATION ULTRASONIC negligible suspended ACCOMPANIED HEMOGLOBIN