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1.
为探讨缺氧 /复氧致原代培养的大鼠大脑皮层神经细胞凋亡中 Bcl-2的表达及银杏叶提取物的调节作用 ,本实验使用胎龄 16~ 17d Wistar大鼠的大脑皮层神经细胞进行原代分离培养。采用 TUNEL染色方法、透射电镜技术确立缺氧复氧神经细胞凋亡病理模型 ,并应用免疫组织化学方法显示缺氧复氧不同时间 Bcl-2基因的表达。结果显示 :缺氧复氧可使大鼠大脑皮层神经细胞发生凋亡 ,随缺氧时间的延长 ,凋亡细胞数渐多 ,至缺氧 8h,复氧 18h达高峰 ,银杏叶提取物预保护可使凋亡细胞数减少 ;随缺氧时间延长 ,Bcl-2表达逐渐下降 ,银杏叶提取物可逆转缺氧复氧时 Bcl-2的表达。结果提示 ,银杏叶提取物对缺氧复氧时Bcl-2表达具有明显的抑制作用 ,这种抑制作用可能是银杏叶提取物对抗缺氧复氧时胎鼠大脑皮层神经细胞发生凋亡的机制之一。  相似文献   

2.
缺氧复氧诱导大鼠大脑皮层神经细胞凋亡的形态学研究   总被引:2,自引:0,他引:2  
目的  应用原代分离培养的Wistar胎鼠大脑皮层神经细胞缺氧复氧模型,探讨缺氧复氧诱导神经细胞凋亡的形态学变化。方法  采用光镜、透射电镜观察并用原位末端标记法(TUNEL)检测DNA断裂。结果  缺氧复氧可使胎鼠大脑皮层神经细胞发生凋亡,凋亡的细胞皱缩,细胞核染色质凝集、边聚呈半月形等多种形式形成核碎块,内质网扩张,线粒体肿长,其它细胞器未见明显变化。结论  凋亡参与了缺氧复氧诱导大脑皮层神经细胞死亡过程。  相似文献   

3.
目的 探讨一氧化氮 (NO)在缺氧复氧诱导神经细胞凋亡中的作用及中药银杏叶提取物的保护机制。方法 实验使用胎龄 16~ 17日Wistar大鼠的大脑皮层神经细胞进行原代分离培养 ;采用Wright Giemsa染色 ,光镜、透射电子显微镜观察 ;原位末端标记法确立缺氧复氧神经细胞凋亡病理模型 ;应用NADPH d组织化学方法检测神经细胞一氧化氮合酶 (NOS)的表达并用计算机图像分析系统进行定量检测。 结果 缺氧复氧可以使大鼠大脑皮层神经细胞发生凋亡 ,随缺氧时间的延长 ,凋亡细胞数渐多 ,至缺氧 8h复氧 18h达高峰 ;在缺氧 2h(H2 R0 组 )和缺氧 8h复氧 18h(R8R1 8)组中神经细胞NOS表达均显著增高 ,与正常对照组比有显著性差异 (P <0 0 1;P <0 0 5 )。EGB能显著抑制此双时相NOS活性的增强 ,并明显降低神经细胞凋亡率。 结论 缺氧复氧损伤可诱导培养的大鼠大脑皮层神经细胞发生凋亡。NOS表达增强从而使NO产生增加可能是缺氧复氧诱导神经细胞凋亡的机制之一。银杏叶提取物 (EGB)经下调NOS表达活性 ,抑制NO的产生保护培养的大鼠大脑皮层神经细胞免于凋亡。  相似文献   

4.
季凤清  岳旭  孙海梅  郭艳茹  郭崇洁  赵天德 《解剖学报》2001,32(4):338-342,T011
目的 探讨缺氧复氧致原代培养的大鼠大脑皮层神经细胞凋亡中Bcl-2、Bax基因蛋白的表达及其与凋亡的关系。方法 用胎龄17-18d Wistar大鼠的大脑皮层神经细胞进行原代分离培养。采用TUNEL染色方法、流式细胞术确立缺氧复氧神经细胞凋亡病理模型,并用免疫组织化学方法显示缺氧复氧不同时间Bcl-2、Bax基因的动态表达。结果 1.缺氧复氧可以使大鼠大脑皮层神经细胞发生凋亡,在分别缺氧2、4、6、8h,复氧0h和18h组中,缺氧4h开始出现凋亡细胞,随缺氧时间的延长,凋亡细胞数逐渐升高,两者呈显著负相关,而凋亡的发生也与Bax基因、Bcl-2基因表达呈显著正、负相关性。在缺氧复氧组中,未发现相关性。结论 缺氧复氧可致胎鼠大脑皮层神经细胞发生凋亡;缺氧复氧所引起Bcl-2基因表达增高,Bax基因表达降低,可能是胎鼠大脑皮层神经细胞发生凋亡的机制之一。  相似文献   

5.
本文研究了缺氧复氧时原代培养的大鼠神经细胞 NOS的动态表达及银杏叶提取物的调节作用 ,藉以探讨 NO在缺血缺氧导致神经细胞损伤时的作用以及银杏叶提取物的保护机制。实验使用胎龄 15~ 17d大鼠的大脑皮层神经细胞进行原代分离培养 ,建立缺氧复氧神经元损伤模型。实验分为正常对照组、单纯缺氧组、缺氧复氧组和银杏叶提取物处理组。应用 NADPH-d组织化学方法观察神经细胞 NOS的动态表达 ,并用图象分析仪进行定量检测。结果 :缺氧复氧可以使神经细胞的 NOS呈双时相的升高 :在单纯缺氧 2、4、6、8h组及缺氧加复氧 18h组中 ,缺氧 2 h组及缺氧 8h复氧 18h组与对照组相比 NOS阳性细胞数量增多 ,染色加深 ,酶活性增强 ,经统计差异具有显著性 (P<0 .0 1)。其它组与对照组比较无明显差异。中药银杏叶提取物可以抑制上述两组的NOS活性增强。本文结果提示 :缺氧及缺氧复氧可以使神经细胞 NOS活性呈双时相增强 ,NO的升高可能是缺氧复氧导致神经细胞损伤的原因之一 ;银杏叶提取物对缺氧复氧导致的神经细胞损伤的保护作用可能是通过下调 NOS活性而实现的  相似文献   

6.
人参皂苷Rb1对大鼠胎鼠海马神经细胞凋亡的影响   总被引:31,自引:3,他引:28  
目的:以原代培养的大鼠胎鼠海马神经细胞缺氧/缺糖再给氧为模型,观察人参皂苷Rb1对神经细胞凋亡的抑制作用。方法:流式细胞术检测凋亡细胞百分率,荧光显微镜观察细胞形态学变化和坏死细胞百分率,同时,测定细胞LDH的释放和NO的产生量。结果:神经细胞缺氧/缺糖5 h后再给氧可诱导神经细胞凋亡和细胞坏死,并显著增加LDH的释放和NO的产生,并随再给氧时间的延长而增加。人参皂苷Rb1能降低神经细胞凋亡及坏死的百分率,减少LDH的释放和NO的过量产生,人参皂苷Rb1的作用随剂量增加而作用增加。结论:人参皂苷Rb1具有拮抗海马神经细胞凋亡的作用,这种作用可能与降低或抑制NOS活性,减少NO的过量产生有关。  相似文献   

7.
本研究用原代混合培养的 Wistar胎鼠大脑皮质神经细胞 ,给予不同时间的缺氧复氧 ,观察其一氧化氮的代谢中间产物亚硝酸盐的动态变化以及诱导型一氧化氮合酶抑制剂氨基胍和银杏叶提取物对一氧化氮的调节作用。结果表明 :缺氧复氧可造成培养大鼠的大脑皮质神经细胞一氧化氮双相升高。即 :在缺氧早期 (缺氧 2 h)可见一氧化氮一过性升高 ,然后很快恢复至正常水平 ;在缺氧 8h、复氧 18h后可见第二次一氧化氮升高。于缺氧前 1h在细胞培养上清液中分别加入氨基胍 (0 .5 m mol/L)和银杏叶提取物 (5 0 μg/ml) ,发现氨基胍可有效地抑制缺氧复氧晚期培养的大鼠大脑皮质神经细胞一氧化氮升高 ,但不能抑制缺氧早期一氧化氮的产生 ;而银杏叶提取物可有效地抑制缺氧复氧诱导的一氧化氮双相升高。提示 :在混合培养的胎鼠大脑皮质神经细胞缺氧复氧损伤模型中 ,一氧化氮的双相升高是由不同亚型的一氧化氮合酶所介导 ,其早期升高可能为神经元型一氧化氮合酶活性上调所致 ,而其晚期升高则是诱导型一氧化氮合酶活性增强的结果 ;银杏叶提取物可抑制缺氧复氧时神经元型和诱导型一氧化氮合酶的活性从而降低一氧化氮的产生而完成其神经保护作用  相似文献   

8.
目的:观察β-肾上腺素能刺激与缺氧/复氧损伤对离体小鼠心脏细胞凋亡的影响。 方法: 逆行灌注离体小鼠心脏,观察不同剂量异丙基肾上腺素(Iso)和不同时间缺氧/复氧心肌细胞凋亡率的变化,并观察β1-肾上腺素能受体阻滞剂、caspase-拮抗剂、Bcl-2对其凋亡率的影响,以TUNEL法检测心肌细胞凋亡率。 结果: 单独Iso未引起心肌细胞凋亡率的变化,但可增加缺氧/复氧所诱导的细胞凋亡率;Bcl-2转基因鼠细胞凋亡率明显低于正常小鼠;β1-受体拮抗剂(美托洛尔)及caspase -拮抗剂(zVAD.fmk)可明显抑制Iso和缺氧/复氧所致细胞凋亡。 结论: β-肾上腺素能受体激动剂可促使缺氧/复氧所诱导心肌细胞凋亡,其诱导凋亡的作用主要通过β1-受体介导,β1-受体拮抗剂可抑制二者共同作用所诱导心肌细胞凋亡。  相似文献   

9.
目的: 观察蒺藜皂苷(TTLS)对缺氧/复氧诱导的大鼠皮层神经元凋亡及细胞内游离钙离子浓度变化的影响。方法: 原代培养大鼠皮层神经元,建立缺氧/复氧损伤的皮层神经元凋亡模型。比色法测定细胞乳酸脱氢酶(LDH)释放漏出率;Annexin V-FITC/PI双染,流式细胞仪定量分析细胞凋亡百分率;Fluo-3荧光染色,激光扫描共聚焦显微镜观察细胞内钙平均荧光值变化。结果: 缺氧3 h复氧12 h可诱导出皮层神经元凋亡,引起细胞内钙离子浓度增高,高于对照组(P<0.01)。蒺藜皂苷(0.025 g/L)能明显降低缺氧/复氧诱导的神经元凋亡,并可降低细胞内钙浓度,与模型组比较有显著差异(P<0.01)。结论: 蒺藜皂苷可降低由缺氧/复氧诱导的皮层神经元的凋亡,减轻细胞损伤,这种作用机制可能与其抑制神经细胞内钙超载有关。  相似文献   

10.
目的:探讨银杏叶提取物(ginkgo biloba extract,GBE)对缺糖缺氧-复糖复氧损伤新生大鼠皮层神经干细胞(neural stem cells,NSCs)的保护作用及其机制。方法:采用无血清法培养新生大鼠皮层NSCs,对NSCs进行缺糖-缺氧结合复糖-复氧处理。实验分为对照组、缺糖-缺氧结合复糖-复氧组和GBE组,MTT法检测细胞活性,DAPI染色检测原代培养细胞的凋亡,比色法测定乳酸脱氢酶(LDH)漏出率,流式细胞仪检测传代细胞的凋亡率,免疫荧光染色观察细胞的增殖分化的能力。结果:与缺糖缺氧-复糖复氧组相比,GBE明显提高了细胞的活性、存活率(P<0.05),同时降低了LDH漏出率和凋亡率(P<0.01)。DAPI染色显示:GBE可明显逆转缺糖缺氧导致的细胞凋亡。免疫荧光双标显示:与对照组相比,缺糖缺氧-复糖复氧组明显抑制了细胞Nestin/BrdU和Nestin/Tuj-1的表达;而与缺糖缺氧-复糖复氧组相比,GBE可显著促进细胞Nestin/BrdU和Nestin/Tuj-1的表达。结论:GBE能够增强皮层NSCs活性,减少细胞凋亡,促进细胞增殖、分化。提示GBE能够通过有效调节NSCs凋亡相关基因和促进细胞增殖与分化,进而对缺糖缺氧-复糖复氧损伤皮层NSCs起到保护作用。  相似文献   

11.
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   

12.
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   

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.
15.
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   

16.
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   

17.
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   

18.
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   

19.
Starting with the integument, we see many organs are contractile sacs or multiples thereof, which tubes or bags constitute the major part of the entire body. Recognition of this basic unit and its characteristics sheds new light, individually and collectively, on many disorders previously considered unrelated. Muscular tears and perforations develop in the walls of these chambers, being no way peculiar to those organs, wherein, hydrochloric acid occurs. So, it is not necessary to explain the absence of excessive acid from patients who exhibit holes in the gastric, uterine, aortic, duodenal, rectal, pulmonary, retina, and other walls. Muscle, not acid is the great common factor relating idiopathic disorders in the gastrointestinal tract to each other and to similar diseases in other systems. When the units are linked together, the lesions tend to appear as arthropathies, i.e. at the joints. Rephrasing common-place observations, frees us from conventional, conceptual cul-de-sacs. An observation is only as good as its interpretation, so all possibilities must be considered, otherwise, we will remain blinded by our misconceptions.  相似文献   

20.
Zusammenfassung Der Einfluß von verschiedenen Nahrungsmitteln auf Methoden zur Bestimmung von Adrenalin (AD), Noradrenalin (NA), Vanillinmandelsäure (VMS), Metanephrinen (MN), Homovanillinsäure (HVS) und 5-Hydroxyindolessigsäure (5-HIE) im 24 h-Harn zur Diagnose des Phäochromozytoms bzw. Karzinoid-Syndroms wurde untersucht. Die in die Untersuchung einbezogenen Nahrungsmittel waren: Tee, Kaffee, Mandeln, Ananas, Käse, Walnüsse, Vanillepudding, Bananen, Tomaten und Milchschokolade. Außerdem wurde der Einfluß des Zigarettenrauchens auf die Bestimmung von AD, NA, VMS und MN untersucht.Walnüsse führten zu einer starken Erhöhung der 5-HIE-Ausscheidung. Bananen erhöhten die Ausscheidung von AD, NA, VMS, MN und 5-HIE. Kaffee und Ananas bewirkten eine geringe Zunahme der MN-Werte. Rauchen von 20–30 Zigaretten/Tag beeinflußte keine der vier Variablen.Wenn die beschriebenen Methoden benutzt werden, sollte lediglich auf den Verzehr von Bananen und Walnüssen vor und während der Harnsammelperioden verzichtet werden, da die oberen Normgrenzen im Harn überschritten werden könnten. Ein Verzicht auf Kaffee und Ananas in normalen Mengen ist nicht erforderlich. Es besteht kein Anlaß, weiterhin die bisherigen umfangreichen Restriktionen der übrigen Nahrungsmittel beizubehalten.  相似文献   

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