苯丙胺对大鼠学习能力和海马结构GFAP阳性细胞结构的影响

目的观察苯丙胺对大鼠学习能力、GFAP免疫阳性细胞结构和亚细胞结构的影响。方法苯丙胺腹腔注射SD大鼠,用水迷宫检测其空间辨别性学习能力,用免疫组织化学方法观察海马结构胶质纤维酸性蛋白(GFAP)免疫阳性细胞的形态变化;用电镜方法检测GFAP免疫阳性细胞超微结构变化。结果学习能力检测发现,在14d以前,苯丙胺组大鼠较生理盐水组的平均运行时间和平均潜伏期缩短(P0.05);在15～28d,苯丙胺组大鼠较生理盐水组正确率降低(P0.05);在29～42d,苯丙胺组大鼠较生理盐水组正确率降低、平均运行时间延长(P0.05)。GFAP阳性细胞形态学观察发现,正常对照组大鼠海马结构星形胶质细胞主要分布在海马以及齿状回的多形层和分子层;生理盐水组大鼠海马结构星形胶质细胞分布与游水组相似,但细胞突起变长及增粗,分支增多,且各亚区比正常对照组相应亚区的星形胶质细胞数量增多(P0.05);苯丙胺组大鼠海马星形胶质细胞分布与正常对照组相似,但细胞突起变长、增粗和分支增多更明显,各亚区的星形胶质细胞比正常对照组和生理盐水组相应亚区增多(P0.05);电镜观察发现苯丙胺组大鼠脑内星形胶质细胞增生肥大,亦可见退变星形胶质细胞。结论在本实验条件下,苯丙胺导致大鼠空间辨别性学习记忆能力下降,引起大鼠海马结构星形胶质细胞增生和损害。     

大鼠在学习记忆时内侧隔核星形胶质细胞GFAP表达的变化

目的观察大鼠在空间辨别性学习时内侧隔核内星形胶质细胞GFAP表达的变化,为星形胶质细胞在学习记忆过程中的作用提供形态学依据。方法30只雄性SD大鼠随机分为对照组、模型5d组和模型10d组。Morris水迷宫训练大鼠建立模型,免疫细胞化学S-P法染色以GFAP标记星形胶质细胞,用体视学方法对星形胶质细胞GFAP的表达进行定量分析。结果大鼠经Morris水迷宫训练5d和15d,即建立了空间辨别性学习记忆模型后,内侧隔核的星形胶质细胞GFAP的表达与对照组相比均有显著的统计学意义(P<0.01)。结论星形胶质细胞参与空间辨别性学习记忆过程。     

大鼠空间辨别性学习记忆活动对海马结构Ephrin-A3表达的影响

为了探讨大鼠获得空间辨别性学习记忆活动对导向分子ephrin-A3表达的影响,本研究采用免疫组织化学染色和Western blot方法对模型组、游水组和对照组大鼠海马内ephrin-A3的表达部位和表达量进行对比研究。免疫组织化学染色结果显示模型组、游水组和对照组海马结构内各亚区和各层内均可见ephrin-A3样免疫阳性产物分布,模型组大鼠海马CA3区辐射层和腔隙层尤为明显;Western blot方法检测模型组大鼠海马结构内ephrin-A3阳性产物平均积分光密度值明显高于游水组和对照组。模型组内训练14d的大鼠海马结构内ephrin-A3阳性产物平均积分光密度值高于训练7d和21d。以上研究结果提示eph-rin-A3的表达与大鼠空间辨别性学习记忆活动有密切关系。     

海马内注射LPS后诱导大鼠皮质星形胶质细胞活化和PirB的表达

目的:探讨海马内注射LPS(lipopolysaccharide,LPS)后,大鼠皮质神经元和星形胶质细胞PirB(paired-immunoglobulin-like receptor B)的表达变化。方法:成年SD大鼠,分为对照组和实验组,用免疫组织化学法检测大鼠脑皮质PirB的表达及星形胶质细胞GFAP的表达变化,免疫荧光双重标记技术,观察星形胶质细胞与PirB阳性细胞的共存。结果:PBS注射的对照组动物脑皮质Ⅴ层内可见PirB阳性神经元样细胞,呈圆形、卵圆形和锥体形,免疫反应产物呈棕色、主要位于细胞膜上;海马内注射LPS 30 d后,PirB阳性神经元样细胞和PirB阳性神经胶质样细胞主要分布于皮质Ⅳ、Ⅴ层,免疫反应产物位于胞质和突起内;另外,可见大鼠梨状皮质、内嗅皮质内GFAP阳性星形胶质细胞明显被激活,表现为细胞胞体相对增大,突起变粗。PirB分别和MAP-2、GFAP、CD11b免疫荧光双重标记染色显示:PirB和MAP-2阳性神经元的胞体存在共定位;PirB与GFAP阳性染色存在部分共定位,但未见PirB与CD11b阳性染色双标细胞。结论:LPS能诱导大鼠皮质星形胶质细胞活化和PirB蛋白表达上调,而且部分活化的星形胶质细胞表达PirB,PirB可能参与脑内炎症突触可塑性改变和学习记忆功能缺失的免疫调节。     

银杏内脂B抑制脂多糖诱导的神经炎性细胞毒作用

目的:探讨血小板活化因子受体拮抗剂银杏内脂B(BN52021)抑制细菌脂多糖诱导的脑内炎症反应的神经保护作用。方法:SD大鼠随机分为对照组,模型组和治疗组。Morris水迷宫检测学习和记忆功能,免疫组织化学法检测脑内GFAP阳性星形胶质细胞、OX-42阳性小胶质细胞在颢叶皮质、海马及基底核中的表达。结果:脂多糖(LPS)第4脑室注射使模型动物学习和记忆功能减退,模型组GFAP阳性星形胶质细胞和OX-42阳性小胶质细胞在颞叶皮质、海马及基底核中细胞数量明显增加。BN52021治疗后,对照组和治疗组水迷宫逃避潜伏期、平台象限游泳距离百分比与模型组均有显著性差异;GFAP阳性星形胶质细胞和OX-42阳性小胶质细胞在颞叶皮质、海马及基底核中细胞数量明显减少和阳性染色灰度上升。结论:血小板活化因子受体拮抗剂可抑制LPS诱导的脑内神经炎症,对阿尔茨海默病和艾滋病相关痴呆等以中枢炎症为病理特征的神经退行性变均有治疗作用。     

细胞外调节蛋白激酶在体外培养下大鼠大脑皮质星形胶质细胞的表达

目的:研究大鼠大脑皮质星形胶质细胞细胞外调节蛋白激酶(ERK)表达.方法:用生后2～3d SD大鼠,在无菌条件下取大脑皮质,制备细胞悬液,以GFAP鉴定星形胶质细胞;用免疫细胞化学方法研究星形胶质细胞ERK1表达.结果:星形胶质细胞的纯度达95%以上,ERK1免疫阳性物质呈棕黄色,分布于星形胶质细胞胞体与突起中.结论:培养的大鼠星形胶质细胞表达ERK1,其可能与星形胶质细胞信号转导有关.     

糖尿病模型大鼠海马区星形胶质细胞活化与凋亡的观察

目的:探讨糖尿病高血糖状态对于大鼠海马星形胶质细胞的影响。方法:应用链脲佐菌素(STZ)诱导Ⅰ型糖尿病SD大鼠模型,分为糖尿病模型1、2、3、4周和5周组(DM1,DM2,DM3,DM4,DM5),同周龄SD大鼠作为对照组。采用免疫荧光、免疫组化和Western Blot等技术,对比观察糖尿病大鼠海马区星形胶质细胞的形态、caspase-3和GFAP的表达情况。结果:免疫荧光和免疫组化检测结果显示:DM1和DM2大鼠海马区星形胶质细胞的胞体增大,突起增粗;DM3和DM4大鼠海马内星形胶质细胞的突起增粗、变长,其数量明显多于正常对照组(P0.05);而DM5大鼠海马内星形胶质细胞的突起僵硬,细胞数量有所减少,但仍高于正常对照组(P0.05)。Western Blot结果显示:DM3,DM4,DM5大鼠海马区GFAP含量明显高于对照组和DM1,DM2(P0.05)。caspase-3/GFAP免疫组化双标结果显示:DM1和DM2大鼠海马区偶见caspase-3阳性标记的星形胶质细胞;而DM3,DM4,DM5大鼠海马区caspase-3/GFAP双标细胞数明显多于正常对照组(P0.05);其中DM5双标阳性细胞数明显多于DM3和DM4(P0.05)。结论:糖尿病高血糖早期可激活星形胶质细胞,持续性糖尿病高血糖可诱导海马区星形胶质细胞活化的抑制,并引起星形胶质细胞凋亡。     

成年大鼠脊髓完全性横断后星形胶质细胞的时空分布及其变化

本研究以成年大鼠脊髓完全性横断模型研究反应性胶质细胞的时空分布和变化。将30只成年Wistar大鼠随机分为5组:正常对照组,T9横断伤1周、2周、4周和8周组,每组6只。利用免疫组织化学方法及图像分析系统对各组动物脊髓内星形胶质细胞的时空分布和变化进行观察和分析。结果显示:脊髓横断组胶质纤维酸性蛋白(GFAP)阳性的星形胶质细胞数目较正常对照组明显增加(P<0.05);距损伤近侧端较距损伤远侧端的GFAP阳性星形胶质细胞数目增加显著(P<0.05);脊髓横断组髓磷脂碱性蛋白(MBP)阳性的少突胶质细胞数目的时间及空间分布与正常对照组相比无统计学差异(P>0.05)。实验结果提示,星形胶质细胞是胶质瘢痕的主要成分,而少突胶质细胞在瘢痕形成过程中并非是反应活跃的成分。     

雷公藤内酯醇对大鼠大脑皮质内注射β-淀粉样蛋白后星形胶质细胞及胆碱能纤维的影响

目的:探讨雷公藤内酯醇(TP)对大鼠大脑皮质内注射β-淀粉样蛋白(Aβ)后星形胶质细胞及胆碱能纤维的影响.方法:采用GFAP免疫组织化学方法、AChE组织化学方法检测各组大鼠大脑皮质星形胶质细胞和胆碱能纤维的表达.结果:Aβ组大鼠大脑皮质GFAP阳性星形胶质细胞数量、平均面积和平均光密度明显高于对照组,用药组大鼠大脑皮质GFAP阳性星形胶质细胞数量、平均面积和平均光密度较Aβ组明显减少;Aβ组大鼠大脑皮质胆碱能纤维密度明显低于对照组,用药组大鼠大脑皮质胆碱能纤维密度较Aβ组明显升高.结论:TP能抑制Aβ诱导的星形胶质细胞的活化,减轻Aβ所致的胆碱能纤维损害.     

热应激对大鼠脑桥臂旁核Fos和GFAP表达的影响

为了探讨急性热应激(heat stress,HS)后大鼠脑桥臂旁核Fos蛋白及胶质原纤维酸性蛋白(glial fibrillary acidic protein,GFAP)的表达变化,本实验将大鼠置于恒温恒湿温度舱内,舱内温度调至24℃、34℃、38.5℃或42℃、湿度为60%,建立HS大鼠模型,1h后结束刺激,立即断头取脑,应用免疫组织化学染色方法检测脑桥臂旁核内Fos蛋白和GFAP的表达情况。结果显示:脑桥臂旁核内可见大量的Fos样免疫阳性神经元和GFAP样免疫阳性的星形胶质细胞,其中在24℃~38.5℃组Fos蛋白的表达随温度增加而增加,38.5℃组为高峰,而在42℃组Fos蛋白表达又有所减少。GFAP样免疫阳性星形胶质细胞在34℃组出现胞体变大,突起增粗的现象,且细胞数量增加,38.5℃组最显著,但在42℃组星形胶质细胞的数量则有所减少,并出现胞体形态不规则、突起断裂的现象。本实验结果表明脑桥臂旁核参与热应激反应的神经免疫调节,可能为此调节通路的中继站之一。     

Renal dysplasia and asplenia in two sibs

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.     

Schizophrenia in a North Swedish geographical isolate, 1900–1977. Epidemiology, genetics and biochemistry

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.     

The dominant diseases of modernized societies as omega-3 essential fatty acid deficiency syndrome: Substrate beriberi

About 1900, modern food selection and processing caused widespread $\text{epidemics}$ 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 $\text{panh}$ypovitaminosis B, i.e., a mixture of $\text{substrate}$ beriberi and $\text{substrate}$ pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse $\text{endemic}$ 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 $\text{primates}$. 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.     

What will studies of Fulani individuals naturally exposed to malaria teach us about protective immunity to malaria?

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.     

'Very sore nights and days': the child's experience of illness in early modern England, c.1580-1720

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.     

Guidelines for the Validation and Use of Immunoassays for Determination of Introduced Proteins in Biotechnology Enhanced Crops and Derived Food Ingredients

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.     

Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)

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.     

HLA in North Colombia Chimila Amerindians

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.     

The case for allele‐specific recognition by the TCR

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.