建立一种用重组蛋白检测抗口蹄疫病毒抗体的间接ELISA方法

目的研究以重组蛋白作为包被抗原检测口蹄疫病毒（FMDV）感染后的动物血清中特异性抗体的可能性,为建立一种非病毒颗粒的ELISA检测试剂盒提供实验依据。方法利用自行构建表达的O型口蹄疫病毒VP1表位肽重组蛋白（VP1epi）作为包被抗原,采用间接ELISA方法确定抗原的最佳工作浓度和包被方法,优化各项实验条件,并以FMDV感染后的豚鼠血清作为标准阳性血清确定ELISA方法的特异性和灵敏度。结果FMDV感染后的阳性豚鼠血清可以很好地识别VP1epi重组蛋白,用此蛋白包被检测抗FMDV抗体的灵敏度可达1∶3200,并证明所检测的抗体是FMDV特异性的。结论VP1epi重组蛋白可以替代FMDV颗粒用于建立检测抗FMDV抗体的ELISA试剂盒。     

恒河猴骨髓间充质干细胞分离培养及其生长特性

采用密度梯度离心和贴壁筛选方法分离纯化了恒河猴骨髓间充质干细胞(mesenchymal stem cells from bone marrow of Rhesus monkey,RhBMSCs);通过表面抗原检测和核型分析对细胞进行了初步鉴定;通过生长曲线的绘制和细胞凋亡的检测探讨了细胞的生长特点。本实验获得的RhBMSCs形态以梭型为主,核型正常,CD29表达率为99.2%,CD34、CD45、HLA-DR表达率均低于3.2%,RhBMSCs表型符合间充质干细胞的特点,且纯度较高,细胞生长旺盛,但倍增时间有随传代数的增加而逐渐延长的趋势。本实验探讨了RhBMSCs的体外分离、扩增培养及鉴定的方法,并对其生长特点进行了初步观察,这不仅有助于进一步了解与之近似的人的骨髓间充质干细胞的相关特性,而且为以猕猴为对象的BMSC定向分化和组织修复等动物体内实验打下了基础。     

急性分离的大鼠骶髓后连合核神经元由抑制性氨基酸诱导的电流反应(英文)

应用制霉菌素穿孔全细胞电压钳技术．在急性分离的大鼠骶髓后连合核（SDCN）神经元上，研究抑制性氨基酸诱导的反应的电生理学和药理学特性。当钳制电压为-40mV时，γ-氨基丁酸（GABA）、甘氨酸（Gly）和牛磺酸（Tau）均诱导产生内向电流。它们的EC50值分别是GABA5．2×10-5M，Gly4．0×10-5M及Tau1．6×10-4M。其Hill系数分别为GABA1．21，Gly1．27和Tau1．23。所有这些电流均在膜电位为-1．8mV左右时翻转。此外．Tau和Gly反应问还存在很强的交叉脱敏。结果提示，GABAA，Gly和Tau作为递质，通过受体Cl-通道复合体．在调节SDCN社经元伤害性传递中可能有重要作用。     

乙酰胆碱酯酶阳性神经元在鼠脑的分布和形态特征

本文用乙酰胆碱酯酶(AChE)再生技术,研究AChE阳性神经元在鼠脑的分布和形态特征。按其染色程度,可见强度、中度和轻度三种染色细胞。强染色细胞多数是较大的多极细胞,主要分布于纹状体、基底前脑、下丘脑、黑质、红核、蓝斑,腹侧被盖区、臂旁核、桥被盖核和脑神经运动核。本文将AChE染色结果和胆碱乙酰转移酶(ChAT)免疫组织化学资料进行了比较,对AChE和胆碱能神经元的关系,以及AChE阳性神经元的性质和意义,进行了讨论。     

Stimulation by hCRF of C-peptide release in type 2 diabetics during concomitant opioid receptor blockade

Summary Administration of synthetic human corticotropin-releasing factor (hCRF, 2 µg/kg body weight) during simultaneous application of the opioid antagonist naloxone (1.6 mg i.v. bolus, followed by an infusion at a rate of 1.2 mg/h) produced a significant increase in plasma C-peptide levels of six male Type 2 diabetic patients which even exceeded the postprandial values. This stimulatory effect of hCRF/naloxone on plasma C-peptide was less pronounced in six healthy men. hCRF alone did not provoke any reaction of plasma C-peptide in either group.The possibility of a paracrine, CRF-dependent mechanism in pancreatic islets which somehow involves inhibitory opioid receptors is preferentially discussed. Such a mechanism may underlie the stimulatory action of hCRF/naloxone on B cells and would explain the absent reaction of peripheral venous plasma C-peptide to hCRF alone as well as the amplifying effect of simultaneous opioid receptor blockade.Abbreviations ACTH adrenocorticotropic hormone - C-peptide connecting-peptide - CRF corticotropin-releasing factor - hCRF human CRF - oCRF ovine CRF - min minutes - S.D. standard deviation - S.E.M. standard error of the mean This study was supported by the Deutsche Forschungsgemeinschaft (Go 299/3-2)Dedicated to Professor Dr. N. Zöllner on the occasion of his 65th birthday     

Macrophage antitumor activity in vitro. Comparative analysis of cytolytic, cytostatic, and cytotoxic activities of mouse macrophages and human monocytes

Mouse peritoneal M phi and human blood monocytes were assayed for their antitumor activity in vitro with a cytolysis, a cytostasis and a cytotoxicity test performed in parallel. Both natural and stimulus-induced M phi antitumor capacities were assessed. Results indicate that natural cytolytic activity of unstimulated M phi is generally unable to restrict final tumor cell growth, since it is not coupled with cytostatic capacity. In contrast, exposure of M phi in vitro to either MAF or IFN-beta, besides augmenting M phi cytolytic capacity, induced a very significant cytostatic activity and thus efficiently restricted the survival of tumor cells.     

Some studies on the mechanism of action of antibodies to nerve growth factor.

The effects of antibodies to the nerve growth factor from mouse salivary gland were examined in vitro and in vivo. Treatment of explants of receptive ganglia with antibody and complement did not produce cell damage as judged by the ability of the tissue to respond to nerve growth factor. New-born mice experimentally depleted of or genetically deficient in key complement components were susceptible to the action of the antiserum.These results show that the effect of the antibody is independent of complement and are consistent with the view that it acts by neutralization of endogenous nerve growth factor.     

An Evaluation of Finger Pulse Volume as a Psychophysiological Measure of Anxiety

The present experiment explored the utility of finger pulse volume (FPV) as a measure of anxiety. Subjects were exposed to either a threatening or nonthreatening situation, and indices of physiological arousal (pulse rate (PR) and FPV) and self-report of anxiety (Affect Adjective Checklist (AACL)) were collected. Results indicated that FPV was responsive to changes in experimentally induced anxiety and significantly correlated with PR and AACL, although the strength of these relationships was not substantial. Relevance for psychophysiological theory and the clinical observation of anxiety is discussed.     

THE NEONATAL EVOKED HEART RATE RESPONSE AND THE LAW OF INITIAL VALUE

Two-second long square wave tones at frequencies of 125 and 1000 Hz and 75 db sound pressure were presented to six newborn infants. Mean heart rates were computed for the 10 sec prior to and the 10 sec following stimulus onset, i.e. the prestimulus and stimulus heart rate values respectively. LIV was shown to operate strongly only in the case of the 125 Hz stimulus. Even for this stimulus, LIV depended upon the state of the infant, showing an appropriate negative correlation between prestimulus and stimulus values in regular sleep and quiet wakefulness but a slightly positive correlation in irregular sleep. In randomly selected control periods, the first 5 sec served as prestimulus values and the second 5 sec as stimulus values. Regression coefficients for these control periods did not differ significantly from those during which the stimulus was actually present. In view of the special conditions required for its demonstration, the generality of Wilder's “law” seems to be seriously questioned.     

A common Ile796Val polymorphism of the human SREBP cleavage-activating protein (SCAP) gene

We identified a new common amino acid polymorphism of isoleucine/valine at codon 796 in exon 16 of the gene for human sterol regulatory element binding protein (SREBP) cleavage-activating protein (SCAP), a central regulator of lipid synthesis and metabolism in animal cells. It can be detected as an MslI restriction fragment length polymorphism. The allelic frequencies were: isoleucine (A) allele, 0.57 and valine (G) allele, 0.43. This polymorphism may be useful for genetic studies of disorders affecting intracellular lipid metabolism and hyperlipidemia. Received: August 17, 1999 / Accepted: August 19, 1999