宫内缺氧对新生小鼠额叶皮质神经元内nNOS表达及对成年小鼠学习记忆能力的影响

为探讨孕鼠宫内缺氧对新生小鼠发育时期额叶皮质神经元内nNOS表达及对成年小鼠学习记忆能力的影响,本研究采用Tapanainen建立的缺氧模型致胎龄13、15、17d小鼠宫内缺氧,然后采用Nissl染色观察新生鼠发育时期P1、P7、P14、P28、P90额叶皮质内神经元的数量和形态变化;免疫组织化学染色方法观察新生鼠发育时期P1、P7、P14、P28、P90脑组织内nNOS阳性神经元的表达;Morris水迷宫实验检测P90小鼠的学习和记忆能力。结果显示:与正常组比较,宫内缺氧组小鼠额叶皮质神经元数量明显减少,额叶皮质神经元内nNOS的表达明显减弱。宫内缺氧组小鼠逃避潜伏期延长及穿环次数明显减少。以上结果提示宫内缺氧可导致新生鼠额叶皮质神经元数量明显减少及nNOS的表达也明显减弱,并引起成年小鼠学习记忆能力降低。     

单克隆抗体2A7亲和层析法纯化红细胞膜表面的CD59分子

用抗ＣＤ５９单抗２Ａ７与ＣＮＢｒ－Ｓｅｐｈａｒｏｓｅ４Ｂ偶联制备亲和层析柱，从正常人红细胞膜蛋白抽提物中分离纯化出ＣＤ５９分子。本法纯化的ＣＤ５９分子量为１８－２０ＫＤａ对还原剂敏感，与ＭｃＡｂｓｓＭＥＭ４３和１Ｆ５有高亲和性，再掺入豚鼠红细胞后，能够抑制人体补体的反应性溶血，本文还对三株抗ＣＤ５９单抗２Ａ７，ＭＥＭ４３及１Ｆ５的抗原特异性进行了初步分析。     

Prefrontal modulation of tactile responses in the ventrobasal thalamus of rats

Prefrontal cortex (PFC) has been implicated in modulation of sensory information processing in somatosensory cortex. However, it remains unclear whether or not PFC regulates sensory information in thalamus. In the present study, the effect of PFC stimulation on tactile responses of neurons in the ventrobasal thalamus (VB) of the rat was investigated by single-unit recording. PFC stimulation significantly enhanced the signal-noise ratio (tactile responses/background activities) in 16 out of 66 VB neurons (24.2%) that had receptive fields in fore or hind limbs. Such changes can be classified into three different categories: (1) PFC stimulation not only increased the tactile responses, but also suppressed the background activities of neurons (six neurons, 9.1%); (2) PFC stimulation only increased the tactile responses of neurons (five neurons, 7.6%); (3) PFC stimulation only suppressed the background activities of neurons (five neurons, 7.6%). Our results suggest that PFC also modulates somatosensory information at the thalamic level.     

Regulation of the association between PSTPIP and CD2 in murine T cells

Prominent in T cells and natural killer cells, CD2 binding protein 1 (CD2BP1) plays an important role in CD2-mediated adhesion and signal transduction. In the current study, we investigated CD2 and PSTPIP (proline, serine, threonine phosphatase interacting protein, murine homologue of CD2BP1) interactions in purified mouse splenic T cells. PSTPIP associated with CD2 in both resting and activated T cells. Following various stimuli, such as concanavalin A, anti-TCRbeta, anti-CD3epsilon, anti-CD3epsilon/phorbol myristate acetate (PMA), IL-2, or PMA/ionomycin, PSTPIP and CD2 expression, as well as their association, increased in a time-dependent fashion. While PSTPIP expression and CD2 expression were comparable across most groups, the PSTPIP-CD2 association stimulated by anti-CD3epsilon alone was significantly greater than with other stimuli. Stimulation by anti-CD3epsilon plus anti-CD28 induced even greater PSTPIP-CD2 association than anti-CD3epsilon treatment alone, indicating that CD28 initiated signals are involved in regulating this interaction. There was no direct association between CD3epsilon or CD28 and PSTPIP. Tyrosine phosphorylated PSTPIP bound poorly to CD2 compared to dephosphorylated PSTPIP, and protein tyrosine phosphatase was shown to affect both phosphorylation of PSTPIP and the CD2-PSTPIP association. In addition to CD2, PSTPIP associated with CD4, CD8, CD54, and CD62L. CD2 and CD4 ligation reciprocally regulated their association with PSTPIP. These findings indicate that T cell activation, particularly through the CD3 and CD28 signal transduction pathways, regulates PSTPIP-CD2 interactions. PSTPIP likely has additional broader effects through interactions with CD4, CD8, CD54, and CD62L, and this may influence T cell responses to antigen.     

纯化的结核杆菌多肽抗原刺激人γδT细胞的效应分析

目的：探讨从结核杆菌多肽抗原(Mtb-Ag)纯化的多肽(C主肽)对人新鲜外周血γδT细胞的促增殖效应以及对已活化扩增的T细胞再次刺激的激活效应。方法：采用不同剂量的C主肽体外刺激健康人外周血PBMC，培养10天时经流式细胞仪检测细胞表型；另外以γδT细胞活化标志分子CD69的表达为指标，分析C主肽对已被Mtb-Ag激活扩增13天的γδT细胞再次刺激的激活效应。同时以MTT法检测C主肽的再刺激对已活化扩增的γδT细胞的促增殖活性。结果：结核杆菌C主肽对人新鲜的γδT细胞具有显著扩增效应；当C主肽再刺激已经活化的γδT细胞时，可使其显著表达CD69分子，同时对γδT细胞具有显著促增殖活性。结论：结核杆菌C主肽可能是Mtb-Ag发挥特异性激活人γδT细胞的有效成分。     

共聚焦激光扫描显微镜(MRC600)活体观测川芎嗪和去甲基肾上腺素对休克状态下家兔大脑皮质内微循环的影响

目的 :共聚焦激光扫描显微镜活体观测川芎嗪和去甲基肾上腺素对休克状态下家兔大脑皮质内微循环的影响。方法 :在开放颅窗的家兔模型上 ,荧光素标记血浆 ,罗丹明 6G标记WBC ,用共聚焦激光扫描显微镜活体观测川芎嗪和去甲基肾上腺素对休克状态下家兔大脑皮质内微循环的影响 ,并经图像分析系统测量数据 ,用SAS软件包进行统计学分析。结果 :①川芎嗪抗休克效果优于去甲基肾上腺素 ;②去甲基肾上腺素在休克状态下对口径为 60 .15 μm的动脉血管处未引起明显的血管运动 ,而川芎嗪能引起血管运动 ,尤以大剂量川芎嗪引起强烈的血管运动 ;③川芎嗪和去甲基肾上腺素增加或保持血液缘流厚度不变 ,可能是两者抗休克机制发挥作用的途径之一 ;④川芎嗪和去甲基肾上腺素引起血管运动 ,尤以中小血管处明显。结论 :川芎嗪抗休克效果优于去甲基肾上腺素。川芎嗪和去甲基肾上腺素增加或保持血液缘流厚度不变 ,可能是两者抗休克机制发挥作用的途径之一     

Antibodies to HIV-1 gp41 recognize synthetic peptides of human IFN-alpha and IFN-beta

Based on our finding that a common epitope exists between HIV-1 gp41 and human type I interferons (IFN-alpha and IFN-beta), and increased levels of antibodies against human IFN-alpha and IFN-beta were observed in HIV-1-infected individuals, we tried to explain the mechanism of increased levels of antibodies. Mouse antisera recognizing HIV-1 recombinant soluble (rs) gp41 (aa 539-684) interacted with two synthetic peptides sequence-corresponding to the IFN-alpha/beta receptor binding site on human IFN-alpha and IFN-beta, while normal mouse serum (pooled normal sera) did not. The anti-rspg41 antisera after adsorption by IFN-beta sepharose column lost the activity of interaction with both synthetic peptides. In another experiment, rsgp41 could bind to sepharose column conjugated with anti-IFN-beta polyclonal antibodies (IgG). These results indicate that the common epitope on gp41 and type I interferons could induce antibodies recognizing the receptor binding site on IFN-alpha and IFN-beta, suggesting that increased levels of antibodies against IFN-alpha and IFN-beta in HIV-1-infected individuals could be induced by gp41.     

Nasal tolerance in experimental autoimmune myasthenia gravis (EAMG): induction of protective tolerance in primed animals

Nasal administration of μg doses of acetylcholine receptor (AChR) is effective in preventing the development of B cell-mediated EAMG in the Lewis rat, a model for human MG. In order to investigate whether nasal administration of AChR modulates ongoing EAMG, Lewis rats were treated nasally with AChR 2 weeks after immunization with AChR and Freund's complete adjuvant. Ten-fold higher amounts of AChR given nasally (600 μg/rat) were required to ameliorate the manifestations of EAMG compared with the amounts necessary for prevention of EAMG. In lymph node cells from rats receiving 600 μg/rat of AChR, AChR-induced proliferation and interferon-gamma (IFN-γ) secretion were reduced compared with control EAMG rats receiving PBS only. The anti-AChR antibodies in rats treated nasally with 600 μg/rat of AChR had lower affinity, reduced proportion of IgG2b and reduced capacity to induce AChR degradation. Numbers of AChR-reactive IFN-γ and tumour necrosis factor-alpha (TNF-α) mRNA-expressing lymph node cells from rats treated nasally with 600 μg/rat of AChR were suppressed, while IL-4, IL-10 and transforming growth factor-beta (TGF-β) mRNA-expressing cells were not affected. Collectively, these data indicate that nasal administration of AChR in ongoing EAMG induced selective suppression of Th1 functions, i.e. IFN-γ and IgG2b production, but no influence on Th2 cell functions. The impaired Th1 functions may result in the production of less myasthenic anti-AChR antibodies and contribute to the amelioration of EAMG severity in rats treated with AChR 600 μg/rat by the nasal route.     

GPR34-mediated sensing of lysophosphatidylserine released by apoptotic neutrophils activates type 3 innate lymphoid cells to mediate tissue repair

1. Download : Download high-res image (200KB)
2. Download : Download full-size image

     

皮质—网状—脊髓通路——HRP法结合溃变电镜法研究

用ＨＲＰ逆行标记法结合溃变电镜技术，观察了１２只大鼠的蓝斑，外侧网状核，中缝大核，巨细胞网状核在旁正中网状核中皮质纤维终末的超微结构及其与网状脊髓神经元的突触联系。损伤皮质感觉运动区的各例动物，均出现两种溃变型，电子致密型和微丝增生型。前者为皮质的主要溃变型，分布于各核；后者出现很少，只见于外侧网状核。电子致密型终扣有大小两种，大终扣少，有含圆形清亮型小泡，多形清亮型小泡，清亮型和颗粒型小泡并存的