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1.
目的观察猪骨骼肌缺血预适应对心肌缺血再灌注后坏死面积及心肌MMP-2、MMP-9及TIMP-1的影响。方法10只小型猪被随机分为缺血再灌注(I/R)组和远端预适应(RP)组。采用非开胸法建立心脏I/R模型,通过球囊堵塞左股动脉造成骨骼肌短暂缺血。以三硝基四氮唑红确定心肌梗死范围;以免疫组化和RT-PCR法测I/R心肌中MMP-2、MMP-9和TIMP-1表达及骨骼肌RP对此的影响。结果与I/R组相比,骨骼肌RP明显减少心肌梗死范围。在缺血区,RP明显降低MMP-2和MMP-9的表达,增加TIMP-1表达(P<0.05)。且RP明显减弱MMP-2和MMP-9 mRNA的表达,增强TIMP-1的mRNA表达(P<0.05)。结论骨骼肌缺血预适应心肌不仅可减少心肌坏死范围,还可能对心肌间质产生保护作用。  相似文献   

2.
目的:探讨在体条件下,心肌缺血后处理(IPTC)是否具有减轻心肌缺血再灌注(I/R)损伤的作用及其可能机制。方法:采用SD大鼠心肌I/R模型,观察IPTC和缺血预处理(IPC)对心肌梗死面积(IS)的影响,检测磷酸肌酸激酶(CK)、丙二醛(MDA)及超氧化物歧化酶(SOD)含量,研究IPTC对I/R心肌MDA、SOD的影响。结果:IPTC和IPC大鼠IS明显降低(P<0.01),血清中CK、MDA含量显著降低(P<0.01),SOD含量明显升高(P<0.01),两组间IS、CK、MDA、SOD比较均无显著性差异(P>0.05)。结论:与IPC一样,IPTC能有效降低I/R大鼠心肌梗死面积,其机制可能与减少自由基损伤和抗氧化作用有关。  相似文献   

3.
目的: 探讨七氟烷对心肌缺血再灌注内皮细胞促炎作用的细胞间黏附分子-1( ICAM-1)、血管细胞黏附 分子-1( VCAM-1)和E- 选择素表达的影响。方法 :在大鼠心肌缺血再灌注模型的基础上,将大鼠随机分为假 手术组( 对照组)、缺血再灌注损伤组( I/R 组)和七氟烷组;观察各组大鼠手术前、缺血15 min 和再灌注4 h 的 心率、平均动脉压和心率-收缩压乘积( RPP );免疫组织化学法检测心肌组织中CD68+ 巨噬细胞数目、内皮细胞 ICAM-1、VCAM-1 和E- 选择素的表达;TUNEL 染色法检测凋亡细胞的比例。结果:缺血15 min 时,I/R 组和 七氟烷组平均动脉压和RPP 均显著下降;再灌注4 h 时,七氟烷组平均动脉压和RPP 均有所上升,相对于I/R 组, 差异具有统计学意义;与对照组比较,I/R 组内皮细胞ICAM-1、VCAM-1 和E- 选择素的表达均显著升高,七氟 烷则能够有效抑制I/R 引起的内皮细胞促炎分子的表达;对照组CD68+ 巨噬细胞为5.83 个/ 高倍镜视野( HPF), I/R 组数目为55.67 个/HPF,两组间差异具有统计学意义;七氟烷能够显著减少心组织内巨噬细胞的浸润,与I/R 组比较,降低了66.46%;TUNEL 染色结果显示对照组心肌细胞凋亡率2.20%,I/R 组为28.63%,两组间差异明显; 七氟烷能够显著降低心肌细胞的凋亡,相对于I/R 组,降低了51.76%。结论:七氟烷可降低缺血再灌注损伤后内 皮细胞表面促炎分子的表达,减少心肌组织巨噬细胞浸润和细胞凋亡。  相似文献   

4.
目的:建立离体大鼠心肌缺血/再灌注损伤模型,观察二氮嗪(diazoxide,D)后处理对缺血/再灌注损伤离体大鼠心功能及线粒体心磷脂的影响,并探讨ATP敏感性钾通道在二氮嗪后处理心肌保护中的作用。方法:采用Langendorff装置建立离体大鼠心肌缺血/再灌注损伤模型,将SD大鼠随机分为对照组(control)、缺血再灌注模型组(I/R)、二氮嗪后处理组(I/R+D)、5-羟葵酸拮抗二氮嗪后处理组(I/R+5-HD+D),每组8只,均先灌注平衡20 min。Control组:灌注平衡后续灌70 min;I/R组:缺血前灌注4℃ST.Thomas停跳液,全心缺血40 min,再灌30 min;I/R+D组:全心缺血40 min,缺血后给予含二氮嗪(50μmol/L)的K-H液灌注5 min后,再灌25 min;I/R+5-HD+D组:二氮嗪后处理前给予含5-羟葵酸(100μmol/L)的K-H液灌注5 min,再灌20 min。观察各组续(再)灌注末心率、冠脉流出液量、心功能、心肌酶学及心肌线粒体心磷脂的变化。结果:各组续(再)灌注末比较,I/R组较control组及I/R+D组心率减慢、冠脉流出液量降低,心功能明显受损,心肌酶增加,心磷酯含量减少,但与I/R+5-HD+D无明显差异。结论:二氮嗪后处理通过增加线粒体心磷脂含量,减少心肌酶的释放,改善心脏功能,减轻心肌的再灌注损伤,产生心肌保护作用。5-羟葵酸能够完全阻断二氮嗪的心肌保护作用。  相似文献   

5.
大鼠在体心脏缺血后处理模型的建立与优化   总被引:3,自引:1,他引:3  
孙胜  赵秀梅  刘秀华 《中国微循环》2007,11(6):401-403,413
目的建立并优化大鼠在体心脏缺血后处理(I-postC)模型。方法采用冠状动脉左前降支垫扎球囊法建立在体心脏I-postC模型,健康雄性SD大鼠随机分为7组(n=8):缺血/再灌注(I/R)组(冠状动脉左前降支缺血45min/再灌注2h)、缺血预处理(IPC)组(I/R前先行3轮缺血5min/再灌注5min处理)、I-postC组(包括4个亚组,于冠脉缺血45min后先进行3或4轮再灌注30s/缺血30s或再灌注60s/缺血60s后处理后再进行冠脉再灌注)以及假手术(sham)组。氯化三苯四氮唑(TTC)法测定心肌梗死面积,试剂盒检测血浆乳酸脱氢酶(LDH)和心肌组织超氧化物歧化酶(SOD)活性。结果I/R引起明显的心肌梗死和组织损伤,采用冠状动脉左前降支垫扎球囊法进行I-postC可以显著减少I/R后心肌梗死面积,尤以3或4轮再灌注30s/缺血30s组保护作用明显,其梗死区占缺血区百分比分别比I/R组下降30.26%和58.81%(P分别<0.05),与IPC保护效果相近。结论I-postC可以减轻心肌I/R损伤,其中4轮再灌注30s/缺血30s诱导的I-postC在限制心肌梗死面积方面作用最明显,是理想的大鼠在体心脏I-postC模型。  相似文献   

6.
无创性延迟肢体缺血预适应减轻大鼠脑缺血/再灌注损伤   总被引:1,自引:0,他引:1  
目的 研究无创性延迟肢体缺血预适应(NDLIP)对大鼠脑缺血/再灌注后氧化损伤的保护作用及其作用机制。方法 连续3d,每天1次3个循环大鼠左后肢无创性5min缺血、5min再灌注,建立NDLIP模型。实验分4组:假手术组、缺血再灌(I/R)组、早期脑缺血预适应+I/R(ECIP+I/R)组及NDLIP+I/R组。进行神经行为评分,检测脑梗死范围,测定再灌末脑组织中海马和皮层超氧化物歧化酶(SOD)以及丙二醛(MDA)含量。结果 与I/R组相比,ECIP+I/R组及NDLIP+I/R组缺血1h,再灌24h后评分有非常显著的降低(P<0.01);脑梗死范围显著减小(P<0.01)。与I/R组比较,ECIP+I/R 组和NDLIP+I/R组的海马和皮层的T-SOD和Mn-SOD活力均升高(P<0.01); MDA含量明显减少(P<0.01)。结论 对脑缺血/再灌注后的氧化损伤,NDLIP具有与ECIP程度相当的保护作用。  相似文献   

7.
心肌缺血预处置对心肌组织11,12-环氧二十碳三烯酸的影响   总被引:1,自引:1,他引:1  
目的 :观察心肌缺血预处置和再灌注损伤时心肌内源性 1 1 ,1 2 -环氧二十碳三烯酸 (1 1 ,1 2 -epoxye icosatrienoicacid ,1 1 ,1 2 -EET)的改变 ,探讨内源性 1 1 ,1 2 -EET在缺血预处置中的作用。方法 :使用雄性Wistar大鼠 ,通过结扎 (60min)和松开 (30min)冠状动脉左前降支 ,复制心肌缺血 /再灌注模型 ;采用缺血 5min ,再灌注 5min两次造成缺血预处置。实验分 5组 :①假手术组 (sham) ;②缺血再灌注组 (I/R) ;③短阵缺血预处置组 (SI) ;④短阵缺血预处置缺血 /再灌注组 (SI+I/R)。采用气相色谱法测定心肌 1 1 ,1 2 -EET的含量 ,并观察再灌注过程中心功能的变化。结果 :I/R组 +dp/dtmax、-dp/dtmax以及LVDP均低于、心肌 1 1 ,1 2 -EET高于sham组及SI +I/R组 (P <0 0 1 ) ;而SI+I/R组心肌 1 1 ,1 2 -EET也高于sham组 (P <0 0 1 )。结论 :整体动物心肌再灌注使大量内源性 1 1 ,1 2 -EET释放 ,是再灌注损伤机制之一 ;缺血预处置抑制再灌注时心肌 1 1 ,1 2 -EET的增加 ,可能与缺血预处置心肌保护作用有关。  相似文献   

8.
刘剑刚  张蕾  史君鹤  张大武  史大卓 《微循环学杂志》2011,21(3):4-7,11,88,90,93
目的:观察缺血预适应(IPC)、缺血后适应(IPOC)对大鼠心肌组织缺血/再灌注(I/R)损伤后Toll样受体(TLR)及下游炎症因子的影响。方法:SD大鼠60只,通过SPSS软件随机分为假手术组(冠状动脉前降支下置线不结扎,n=15);I/R组(冠状动脉前降支结扎30min,再灌注60min,n=15);IPC组(冠状动脉前降支3次3min/5min的缺血/再灌注循环,然后结扎30min后,再持续灌注60min,n=15);IPOC组(冠状动脉前降支结扎30min,3次10s的缺血/再灌注循环,再持续灌注60min,n=15)。实验结束后测定大鼠血清肌酸激酶同工酶(CK-MB)和肌钙蛋白T(cTNT)水平;氯化硝基四氮唑兰(NBT)染色测定大鼠左室心肌梗死面积;免疫组织化学法测定心肌组织TLR-2、4的表达;酶联免疫吸附法测定心肌组织白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)、单核细胞趋化蛋白-1(MCP-1)和肿瘤坏死因子-α(TNF-α)的含量。结果:与I/R组比较,IPC组、IPOC组大鼠血清CK-MB和cTNT水平显著降低(P<0.01),心肌梗死面积显著减小(P<0.01),心肌组织TLR-2、4表达和炎症因子IL-6、IL-1β、MCP-1、TNF-α含量显著下降(P<0.05,P<0.01);与IPC组比较,IPOC组减小I/R大鼠心肌梗死面积,降低血清CK-MB及心肌组织IL-6等作用和IPC组无显著差异(P>0.05)。结论:IPOC与IPC同样具有减轻心肌I/R损伤程度和缩小心肌梗死范围等作用,抑制TLR-2、4的表达可能是其保护I/R心肌的一个重要途径。  相似文献   

9.
 目的:研究缺血预处理(IP)减轻大鼠肝脏缺血再灌注(I/R)损伤是否涉及前炎症因子白三烯C4(LTC4)。方法:健康成年雄性SD大鼠随机分为3组(每组6只)。I/R组: 采用大鼠部分(70%左右)肝脏缺血60 min再灌注5 h模型,缺血前15 min开始至复灌5 h经颈外静脉输注生理盐水(3 mL·kg-1·min-1);假手术组:只麻醉开腹,不阻断肝脏血流;IP组:在I/R前先阻断肝左、中叶血流10 min,然后开放血流10 min,余步骤同I/R模型组。应用反相高效液相色谱法(RP-HPLC)检查肝组织LTC4含量,同时生化检测血清丙氨酸氨基转移酶(ALT)、天冬氨酸氨基转移酶(AST)活性和肝组织谷胱甘肽(GSH)含量,以及HE染色法检查肝组织学损伤。结果:肝脏IP处理完全逆转了再灌注5 h所致肝组织LTC4含量增加(P<0.05);同时增加肝组织GSH含量,明显降低血清ALT和AST活性(P<0.05),并减轻肝脏组织结构损伤。结论:IP处理减少肝脏I/R期间LTC4堆积,同时伴随血清肝酶释放减少和肝组织结构损伤降低,以及保护肝组织氧化还原状态,表明IP的有利影响可能涉及其在肝脏I/R损伤期间抑制LTC4生成。  相似文献   

10.
目的:探讨肢体缺血后处理对兔急性心肌缺血再灌注损伤的影响及其可能机制。 方法:健康新西兰大白兔30只,随机分为3组(每组10只):对照组(Con)、心肌缺血后处理组(MIP)和肢体缺血后处理组(LIP)。缺血前、缺血后及再灌注结束后分别测定血浆磷酸肌酸激酶(CK)活性和丙二醛(MDA)含量;实验结束后,测心肌梗死面积并检测心肌组织髓过氧化物酶(MPO)活性。 结果:MIP和LIP组心肌梗死面积均明显低于Con组(P﹤0.01);再灌注180 min末血浆CK活性检测证实心肌梗死面积的这种差异;MIP和LIP组再灌注180 min末MDA含量明显低于Con组(P﹤0.01);MIP和LIP组中性粒细胞在缺血心肌的聚集程度,即组织MPO活性(U/100 g)均明显轻于Con组 (P﹤0.01)。 结论:心肌缺血再灌注前肢体短暂缺血具有显著的心肌保护作用。这种远隔器官缺血后处理心脏保护作用可能与减轻活性氧的损伤及抗氧化作用加强有关。  相似文献   

11.
Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

12.
Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

13.
About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

14.
There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

15.
16.
Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

17.
Recent advancements in agricultural biotechnology have created a need for analytical techniques to determine introduced proteins in crops enhanced through modern biotechnology techniques. These proteins are expressed in plant tissues and may be present in food ingredients. Immunoassays are ideally suited for protein detection and may be used as both quantitative and threshold methods. Microplate ELISA and lateral flow devices are two of the most commonly used immunoassay formats for agricultural biotechnology applications. This paper provides general background information and a discussion of criteria for the validation and application of immunochemical methods to the analysis of proteins introduced into plants and food ingredients using biotechnology methods. It is the result of a collaborative effort of members of the Analytical Environmental Immunochemical Consortium. This collaborative effort represents the combined expertise of several organizations to reach consensus on establishing guidelines for the validation and use of immunoassays. Further, the paper offers developers and users a consistent approach to adopting the technology as well as aid in producing accurate and meaningful results.  相似文献   

18.
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts.  相似文献   

19.
HLA-A,-B,-C,-DRB1 and -DQB1 alleles have been studied in Chimila Amerindians from Sabana de San Angel (North Colombian Coast) by using high resolution molecular typing. A frequent extended haplotype was found:HLA-A*24:02-B*51:10-C*15:02-BRB1*04:07-DQB1*03:02 (28.7%) which has also been described in Amerinndian Mayos Mexican population (Mexico, California Gulf, Pacific Ocean). Other haplotypes had already been found in Amerindians from Mexico (Pacific and Atlantic Coast), Peru (highlands and Amazon Basin), Bolivia and North USA. A geographic pattern according to HLA allele or haplotype frequencies is lacking in Amerindians, as already known. Also, five new extended haplotypes were found in Chimila Amerindians. Their HLA-A*24:02 high frequencies characteristic is shared with aboriginal populations of Taiwan; also, HLA-C*01:02 high frequencies are found in New Zealand Maoris, New Caledonians and Kimberly Aborigines from Australia. Finally, this study may show a model of evolutionary factors acting and rising one HLA allele frequency (-A*24:02), but not in others that belong to the same or different HLA loci.  相似文献   

20.
There is a sharp difference in how one views TCR structure–function–behaviour dependent on whether its recognition of major histocompatibility complex‐encoded restriction elements (R) is germline selected or somatically generated. The generally accepted or Standard model is built on the assumption that recognition of R is by the V regions of the αβ TCR, which is not driven by allele specificity, whereas the competing model posits that recognition of R is allele‐specific. The establishing of allele‐specific recognition of R by the TCR would rule out the Standard model and clear the road to a consideration of a competing construct, the Tritope model. Here, the case for allele‐specific recognition (germline selected) is detailed making it obvious that the Standard model is untenable.  相似文献   

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