简介:随着犯罪嫌疑人的反侦查意识及能力加强,接触性检材在现场提取检材中所占的比重越来越大,现场接触性DNA在案件侦破中发挥的作用也日渐明显.由于人在接触物体后,会在物体表面留下相应的微量接触性DNA,对这类接触性检材的检验分析是目前法医物证检验工作的热点和难点.对接触性检材的现场发现、前期处理及DNA的提取方法、扩增方法、电泳以及结果分析等方面对其检验研究进展综述.希望能够为侦查实战工作在接触类检材的现场发现,提取以及成功检测分型方面提供方法和思路.展望:首先,关于接触性检材的分类按接触物体表面质地分更为合理,因为潜在DNA转移的发生,与物体表面质地及样本的湿度密切相关,而且检材的表面质地很大程度上影响实验者提取方法的选择;其次,现勘人员应该及时出现场并且能结合案情科学地提取、包装并运送检材;再次,我们在处理接触类检材必须做到检验时突出重点部位、选择合适的检验策略与方案;最后,根据接触性检材的检测结果下鉴定意见时应十分谨慎.
简介:IBM公司近日发布免费的网络服务技术来协助科学家追踪DNA,与此同时该公司还在不断推动颇有前景的生命科学领域的发展。网络服务的目的是让相关的研究机构连接到独立的应用软件上并分享数据,在AlphaWorks网站上可以下载IBM
简介:PreviousstudieshaveshownthatoligodeoxynucleotidescontainingunmethylatedCpGmotifswereusedasadjuvantsforimmunoregulationandimmuneresponse.ThisstudywastoexploretheactivationeffectsofBifidobacteriaDNAcontainingunmethylatedCpGmotifs(CpGDNA)onmurinemacrophageJ774A.1cells.ThegenomicDNAofBifidobacteriawasextractedandpurified,andthemethylationdegreeofCpGmotifswastested.Thephagocyticabilityofthemacrophageswasdetectedbyflowcytometry.Thecytokines(IL-1β,IL-6,IL-12p40andTNF-α)levelsintheculturesupernatantsofBifidobacteriaDNAtreatedJ774A.1cellswereassayedbyELISA.Thecontentofnitricoxide(NO)wasdetectedbyGriessreagent.AftertreatedwithBifidobacteriaDNAfor24h,NileRedstainincreasedinJ774A.1macrophage,whichsuggestedthatthelipidmetabolismincreasedinthemacrophages.ThephagocyticabilityandlevelsofNOandcytokinesofIL-1β,IL-6,IL-12p40andTNF-αweresignificantlyhigherthanPBSgroupandCTDNAgroup.TheresultsindicatedthatBifidobacteriaDNAcouldactivatemurinemacrophagesJ774A.1,whichcouldprovidescientificbasisfortheresearchandapplicationofmicroorganismDNApreparation.
简介:Hidingdatainthedeoxyribosenucleicacid(DNA)canfacilitatetheauthenticationandannotationofimportantplantvarietyrights.Agrantofplantvarietyrightsforanewplantvarietygivesyoutheexclusiverighttoproduceforsaleandsellpropagatingmaterialofthevariety.Digitalwatermarkingtechniqueshavebeenproposedforawiderangeofapplications,includingownershipprotection,copycontrol,annotation,andauthentication.However,existingdatahidingmethodsforDNAchangethefunctionalitiesofDNAsequences,whichinducemorphologicalchangesinbiologicalpatterns.ThispaperproposesahighcapacitydatahidingschemeforDNAwithoutchangingthefunctionalitiesofDNAsequences.Thisschemeadaptivelyvariestheembeddingprocessaccordingtotheamountofhiddendata.Experimentalresultsshowthattheproposedschemegivesasignificantlyimprovedhidingperformancethanpreviousschemes.Andtherobustnessandsecurityissuesarealsoanalyzed.
简介:刘更另,著名土壤肥料与植物营养专家。1929年2月出生于湖南桃源,1952年毕业于武汉大学,7959年获得苏联季米里亚捷夫农学院副博士学位。曾任河南农事实验场土肥室负责人,中国农业科学院土壤肥料研究所土壤调查室,肥料室副主任,农业科学院土壤肥料研究所祁阳站站长,北京农业大学副教授,中国科学院长沙农业现代化研究所副所长,农业科学院土肥所副所长、所长,农业科学院党纽成员、副院长兼院学术委员会副主任,《中国农业科学》编委会主任兼主编,国务院学位委员会第二、三届学科评审组成员,国家自然科学基金委员会第一至三届学科评审组成员,国家自然科学类第三、四、五届地学书评审组成员,中国工程院农业、轻纺和环境工程学书常委、副主任,国际土壤学会土壤肥力专业委员会委员。中国工程院院士。
简介:摘要本文介绍了DNA纳米机器在生物医学领域的研究与应用。DNA纳米机器是指由DNA分子构造的自组装器件。DNA纳米机器对生物医学领域有着至关重要的意义,尤其在DNA生物传感器,非病毒基因传递,靶向给药,细胞内物质输运,纳米尺度的自组装等方面。
简介:Electrophoresis,chromatography,immunoassay,sequencingandothertimeconsumingap-proacheshavebeendevelopedtodetermineDNAbasemismatching,oxidativelesionorstrandbreaks.Sometimes,however,onlyqualitativeinformationisenoughtodecidewhethermutationhashappenedtoDNAanditsextent.Convolutionspectrometry(CS),anewtechniquetodiscoverultrafmedifferenceonultraviolet(UV)absorptionofdifferentsubstances,isoriginallyemployedtofindoutanysubtlemutationofDNAinducedbyUVradiation.Muta-tiveDNAiscomparedwithegocriteriabasedonthespectraoftheformerDNA,anydifferenceisquantitativelyex-pressedbydispersion(5).Visiblechangescannotbeobservedonsecond-derivativespectrauntilthemutationgets5upto11.48%.DimethylsulfoxideisanintensifierofUV254nminducedDNAmutationandprotectorat365nm,whichissimplyconfirmedbyincreasinganddecreasing5.Everyconvolutionproceduretakeslessthan1min.Convolutionspectrometryprovidesafast,simple,sensitiveandinexpensivealternativetodetermineDNAmutation,andtoscreenanti-mutationalmedicines.
简介:Adetectionofanthracyclineantitumordrugdaunomycin(DNR)reactingwithDNAinsimulatemetabolisminvitrohasbeenmade.ItwasfoundthatDNRcouldreactwithDNAtoformDNR-DNAadducts.TheadductcompositionsofDNRwithfishspermDNAandthermallydenaturatedDNAweredetermined.TheequilibriumassociationconstantKofDNRwithfishspermDNAis1.98×10^5L/molandthatofDNRwithdenaturatedDNAis2.29×10^4L/mol.Semiquinonefreeradicals,metabolicproductsofDNR,candestroybothfishspermDNAanditsthermallydenaturatedDNA.ItisverifiedbyhyperchromiceffectincreaseobservedinUVspectrumandAFMexperiments.ThemechanismofDNAdegradationhasalsobeeninvestigated.Resultsobtainedallowonetoexplainthereasonofsideeffectofanthracyclinedrugandgivethewaytodepress,whichwereofclinicalsignificance.
简介:Eelfamilyisahugeone,inwhichmanykindsofeelsespeciallysomemigratoryeels,bearstrongresemblancetoeachother,andarethereforedifficulttobeidentified.Inthisstudy29randomprimerswereusedtomakeRAPDanalysisforJapaneseseel(Anguillajaponica),Europeaneel(Anguillaanguilla)andPikeeel(Muraenesoxcinereus).Andtotally299fragmentswerecounted.Sharedorspecificfragmentswerecountedandgeneticsimilarityorgeneticdistancewerecalculated.ThegeneticsimilaritybetweenJapaneseeelandPikeeelis0.68andthegeneticdistancebetweenthemis0.32;thosebetweenEuropeaneelandPikeeelare0.72and0.28respectively,andbetweenJapaneseeelandEuropeaneelare0.74and0.25respectively.Themethodhasbeenshowntobesuitabletomolecularidentificationofeels.Itprovidesanalternativeapproachtodeterminetherelationshipbetweenspecies.