老龄大鼠局灶性脑缺血后细胞周期素表达变化及意义

目的:探讨老龄大鼠局灶性脑缺血后细胞周期素表达意义。方法:应用原位末端标记、原位分子杂交、免疫组织化学等方法,分别对老龄大鼠局灶性脑缺血后４ｈ,２４ｈ,５ｄ脑组织中的凋亡细胞,ＣｙｃｌｉｎＤｌｍＲＮＡ,ＣｙｃｌｉｎＤ１,ＣｙｃｌｉｎＡ和ＣｙｃｌｉｎＢ１蛋白表达进行观察。结果:ＣｙｃｌｉｎＤ１ ｍＲＮＡ,ＣｙｃｌｉｎＤ１及 ＣｙｃｌｉｎＢ１蛋白阳性细胞主要见于缺血灶周围,其分布范围及动态变化规律与Ｔｕｎｅｌ阳性细胞一致。但未见ＣｙｃｌｉｎＡ蛋白表达。结论:ＣｙｃｌｉｎＤ１,ＣｙｃｌｉｎＢ１参与了局灶性脑缺血后神经细胞的凋亡过程,此过程可能是细胞周期异常调控的结果。     

Flavopiridol对大鼠局灶性脑缺血后神经元cyclinD1蛋白表达的影响

目的 观察大鼠局灶性脑缺血后神经元内细胞周期蛋白D1(cyclin D1)的蛋白表达与神经细胞凋亡的关系以及Flavopiridol对其的影响.方法 采用线栓法大鼠大脑中动脉持续栓塞模型,应用免疫组化和TUNEL染色方法 观察缺血组、Flavopiridol治疗组(分高剂量FH组和低剂量FL组)和假手术组神经元阳性细胞染色数量及分布情况.结果 cyclin D1蛋白和凋亡细胞分别自缺血后6h和12h开始表达,前者缺血后48h达高峰;后者缺血后72h达高峰,FH组和FL组各相应时间点cyclin D1蛋白表达均明显减少(P<0.01);FL组各相应时间点凋亡细胞明显减少(P<0.01),FH组仅在缺血48h凋亡细胞明显减少.相邻切片可见cyclin D1蛋白表达和凋亡细胞染色区域基本相同.结论 cyclin D1的蛋白表达可能诱发缺血神经细胞的凋亡,Flavopiridol通过抑制cyclin D1的表达而减少缺血后神经细胞的损害,但同时Flavopiridol本身也可能引起神经细胞凋亡.     

大鼠脑缺血再灌注后Bcl-2、Fas蛋白的表达及意义

目的　探讨 Ｂｃｌ２ 及 Ｆａｓ 蛋白在大鼠脑缺血再灌注损伤中的表达及与缺血性凋亡的关系。方法　采用免疫组化方法观察 Ｂｃｌ２ 及 Ｆａｓ 蛋白在脑缺血再灌注后随时间延长动态变化并用图像分析测定二者的免疫强度。结果　脑缺血再灌注后 Ｂｃｌ２、 Ｆａｓ 表达。 Ｂｃｌ２ 蛋白表达于再灌注 ３ｈ 达高峰,再灌注 ６ｈ 其表达呈下降趋势,再灌注 ２４ｈ 仅少数细胞阳性表达。 Ｆａｓ 蛋白表达于再灌注 ６ｈ 达高峰,对缺血较敏感的海马大锥体细胞亦有表达,再灌注 ２４ｈ 其表达减少。结论　 Ｆａｓ 蛋白表达介导了脑缺血后细胞凋亡的发生,并可能参与了迟发性神经元死亡。 Ｂｃｌ２ 表达与神经元存活密切相关,在神经元缺血敏感性方面起重要作用,对神经元起保护作用。     

氟美松对成年大鼠持续性局灶脑缺血后细胞凋亡和Fas基因表达的作用

目的 研究氟美松对成年人局灶性脑缺血后细胞凋亡及相关Ｆａｓ基因表达的作用。方法 健康雄性ＳＤ大鼠随机分成１４组（每组５只）。１～７组为对照组，８～１４组为实验组。用右侧近端大脑中动脉电凝术建立大鼠持续性局灶性脑缺血模型。缺血后１ｈ，实验组动物尾静脉射氟美松（５ｍｇ／ｋｇ），对照组注射生理盐水。分别在缺血后３、６、１２、２４、４８、７２和１２０ｈ取材，用原位末端标记（ＴＵＮＥＬ法）、原位ＲＴ－ＰＣＲ法分别检测缺血后细胞凋亡和Ｆａｓ ｍＲＮＡ表达并进行了半定量分析。结果 氟美松可导致缺血后细胞凋亡提前发生，促进大鼠局灶性脑缺血后Ｆａｓ ｍＲＮＡ的表达，使其表达开始时间提前、表达持续时间延长、表达细胞增多及表达信号增强。结论 氟美松可促缺血后细胞凋亡相关基因Ｆａｓ ｍＲＮＡ的表达，可能是其加重成年大鼠缺血性脑损伤尤其     

神经生长因子对大鼠脑缺血后海马CA1区神经细胞凋亡的影响

目的　研究神经生长因子（ Ｎ Ｇ Ｆ）在缺血性脑损伤中对神经细胞凋亡的影响。方法　采用大鼠 ４ 血管闭塞脑缺血模型， Ｔ Ｕ Ｎ Ｅ Ｌ 方法原位标记 Ｄ Ｎ Ａ 片段，观察脑室内注射 Ｎ Ｇ Ｆ 后海马 Ｃ Ａ１ 区神经细胞凋亡的变化。结果　使用 Ｎ Ｇ Ｆ 后 ３ｄ 海马 Ｃ Ａ１ 区 Ｔ Ｕ Ｎ Ｅ Ｌ 阳性神经细胞数为神经细胞总数的１３．９％ ±１１．６％ ，与缺血对照组（２１．３％ ±１３．７％ ）比较显著减少（ Ｐ＜ ０．０１）。结论　外源性 Ｎ Ｇ Ｆ 对脑缺血所致的神经细胞凋亡可能具有一定的保护作用。     

大鼠局灶性脑缺血再灌流损伤时神经细胞凋亡及其调控基 …

目的 探讨脑缺血再灌流损伤时神经细胞凋亡及其调控基因ｂｃｌ－２的作用。方法 采用大鼠大脑中动脉（ＭＣＡ）阻断模型阻断血液２小时后再灌注，分别在不同再灌注时间将大鼠断头取脑，连续切片分别作ＨＥ、ＴＵＮＥＬ染色及ｂｃｌ－２蛋白免疫组化染色。结果（１）ＭＣＡ阻断后脑缺血周边区部分神经细胞发生凋亡，随着再灌注时间的延长，一定时程内凋亡细胞逐渐增多，２４小时达高峰，各组之间及与假手术组之间差异显著（Ｐ〈０．     

脑缺血再灌流后bFGF基因的表达及MK-801的影响

目的 研究脑缺血再灌流后ｂＦＧＦ基因表达的意义及其机制。方法 采用原位杂交和１免疫组化的方法,观察大鼠脑缺血再灌流后ｂＦＧＦ基因的表达及ＭＫ－８０１对它们的影响。结果 缺血２ｈ再灌流１ｈ可见ｂＦＧＦ表达增高（Ｐ〈０．０５）,ｂＦＧＦ ｍＲＮＡ表达于１２ｈ达高峰,ｂＦＧＦ蛋白于２４ｈ,达高峰;ＭＫ－８０１组与缺血组相比,于再灌流６ｈ～４８ｈ ｂＧＦＧ表达减弱（Ｐ〈０．０５）。结论 局灶性脑缺血再灌流     

β淀粉样蛋白诱导脑内神经元调亡及褪黑素的保护作用

目的 探讨凋亡机制在β－淀粉样蛋白（Ａβ）服内致阿尔茨海默病（ＡＤ）作用中的意义及褪黑素（ＭＴ）对Ａβ脑内神经毒性的干预效果。地将Ａβ１－４０微量注射至大鼠右侧海马ＣＡ１区,７天后,用尼氏染色检测神经元丢失,ＨＥ染色、ＴＵＮＥＬ染色及透射电镜检测细胞凋亡,用免疫组织化ＳＡＢＣ法检测Ｂａｘ／Ｂｃｌ－２表达。结果 Ａβ组右侧海马ＣＡ１区发现大量凋亡细胞,而假手术对照组和生理盐水对照组未发现细胞凋亡;Ａ     

红景天保护缺血再灌注损伤鼠脑细胞的作用及机理研究

目的研究红景天对大鼠脑缺血再灌注损伤的作用。方法４ＶＯ法复制缺血再灌注动物模型;放免法及化学发光法测定乙酰胆碱（Ａｃｈ）、一氧化氮（ＮＯ）及内皮素（ＥＴ）含量;细胞培养观察红景天对神经细胞的作用。结果（１）缺血再灌注组（ＩＲ）Ａｃｈ含量显著低于假手术组（ＳＡＭ）,药物预防后缺血再灌注组（Ｒ＋ＩＲ）及缺血再灌注后药物治疗组（ＩＲ＋Ｒ）较ＩＲ组显著升高。（２）ＩＲ组ＮＯ含量显著高于ＳＡＭ组,Ｒ＋ＩＲ组及ＩＲ＋Ｒ组ＮＯ含量显著降低。（３）ＩＲ组ＥＴ含量显著高于ＳＡＭ组而Ｒ＋ＩＲ组显著降低。（４）红景天甙培养组细胞存活率及ＬＤＨ含量明显高于对照组,ＮＭＤＡ损伤＋红景天甙组细胞存活率明显高于ＮＭＤＡ损伤组,ＬＤＨ含量却明显降低。结论红景天对大鼠脑缺血再灌注损伤时脑神经细胞具有保护作用。     

缺血预处理后Fas蛋白表达与迟发性神经元凋亡的关系初步探讨

目的动态观察缺血预处理后大鼠大脑皮层和海马CA1区神经元凋亡与Fas蛋白表达变化情况,初步探讨缺血预处理后Fas蛋白表达与迟发性神经元凋亡的关系。方法四血管阻断法复制全脑缺血模型,动物随机分为非缺血对照组、预处理对照组、缺血预处理组和缺血组。采用尼氏和TUNEL染色法观察皮层及海马CA1区神经元存活数和凋亡细胞数,免疫组化方法检测Fas蛋白在缺血预处理后表达变化情况。结果缺血组缺血6h在皮质及海马CA1区Fas阳性表达细胞计数升高,12h达高峰;缺血预处理组缺血12h阳性细胞计数升高,24h达高峰。缺血组缺血6h出现凋亡细胞,48h凋亡细胞数达到高峰;缺血预处理组凋亡细胞数较缺血组明显减少。缺血组缺血7d神经元数明显减少,12周时神经元大量减少;缺血预处理组缺血7d时神经元数无明显变化,但12周时神经元同样大量减少。结论全脑缺血可能通过诱导Fas蛋白的表达增多,启动细胞凋亡,导致缺血后神经元凋亡的发生;缺血预处理虽可延缓缺血后神经元的凋亡,但无法提供真正的长时期的神经元保护作用,其有限的保护作用可能是通过延缓Fas蛋白的表达而减缓了神经元凋亡的进程。     

视频脑电图在小儿癫痫诊断中的应用

目的评价视频脑电图(video-EEG)在小儿癫诊断中的应用价值。方法对126例具有发作性症状的患儿进行连续8h的包括清醒、睡眠、诱发试验及必要的认知测验的视频脑电图监测。结果经发作期视频脑电图证实,39例初诊为癫性发作的患儿中14例(35%)为非癫性发作;15例其他症状发作中13例(86%)为非癫性发作。64例样放电患儿中51例(80%)确定发作类型,22例(34%)确定癫类型。视频脑电图可发现短暂轻微的癫发作及样放电引起的一过性认知损伤。结论视频脑电图在排除非癫性发作、确定癫性发作的类型、评价脑电-临床关系方面可提供准确可靠的证据,进一步提高癫的临床诊断水平。     

Storage of lipofuscin in neurons in mucopolysaccharidosis

Summary A histochemical and ultrastructural study was made on the brain of a 23-year-old man with Sanfilippo's syndrome. In accordance with previous reports the cortical nerve cells contained a PAS-positive lipid storage substance. This showed intense autofluorescence in UV-light and was positive with various stains for lipofuscin. The storage material appeared ultrastructurally as inclusion bodies composed of short lamellated membranes, granular material, and vacuoles. In addition, concentrically and transversely lamellated membranous cytoplasmic bodies were observed in the nerve cells. It is concluded that the PAS-positive lipid storage material in the neurons was composed partly of lipofuscin in addition to other lipids presumably glycosphingolipids.Supported by a grant from the Expressen Prenatal Research Foundation     

Neuroprotective properties of memantine in different in vitro and in vivo models of excitotoxicity

The pathogenesis of stroke, trauma and chronic degenerative diseases, such as Alzheimer's disease (AD), has been linked to excitotoxic processes due to inappropriate stimulation of the N-methyl-D-aspartate receptor (NMDA-R). Attempts to use potent competitive NMDA-R antagonists as neuroprotectants have shown serious side-effects in patients. As an alternative approach, we were interested in the anti-excitotoxic properties of memantine, a well-tolerated low affinity uncompetitive NMDA-R antagonist presently used as an anti-dementia agent. We explored in a series of models of increasing complexity, whether this voltage-dependent channel blocker had neuroprotective properties at clinically relevant concentrations. As expected, memantine protected neurons in organotypic hippocampal slices or dissociated cultures from direct NMDA-induced excitotoxicity. However, low concentrations of memantine were also effective in neuronal (cortical neurons and cerebellar granule cells) stress models dependent on endogenous glutamate stimulation and mitochondrial stress, i.e. exposure to hypoxia, the mitochondrial toxin 1-methyl-4-phenylpyridinium (MPP+) or a nitric oxide (NO) donor. Furthermore, memantine reduced lethality and brain damage in vivo in a model of neonatal hypoxia-ischemia (HI). Finally, we investigated functional rescue (neuronal capacity to migrate along radial glia) by memantine in cerebellar microexplant cultures exposed to the indirect excitotoxin 3-nitropropionic acid (3-NP). Potent NMDA-R antagonists, such as (+)MK-801, are known to block neuronal migration in microexplant cultures. Interestingly, memantine significantly restored the number of neurons able to migrate out of the stressed microexplants. These findings suggest that inhibition of the NMDA-R by memantine is sufficient to block excitotoxicity, while still allowing some degree of signalling.     

Role of vincristine in the inhibition of angiogenesis in glioblastoma

Objective: Vincristine, a microtubule-destabilizing drug, was found to exhibit anti-angiogenic effects and anti-tumoral activity. However, the precise mechanism by which vincristine inhibits angiogenesis in glioblastomas is not well understood. Our aim was to investigate whether vincristine affects vascular endothelial growth factor (VEGF) expression in glioblastoma cells and determine whether it is mediated by the downregulation of hypoxia-inducible factor-1α (HIF-1α).

Methods: We investigated the expression of HIF-1α in glioblastoma tissues resected from patients and in human glioblastoma cell lines using immunohistochemistry, Western blot analysis, and immunocytochemistry. In addition to an MTT assay assessing the effect of vincristine on cell proliferation and viability, the effects of vincristine on VEGF mRNA expression and HIF-1α protein were examined using real-time RT-PCR and Western blot analysis under 1% O₂ (hypoxia).

Results: HIF-1α was expressed in the majority of glioblastoma tissues and was detected mainly in the nucleus. Strong immunoreactivity for HIF- 1 α was found often in the hypercellular zones. Under hypoxic conditions, HIF-1α protein levels in the glioblastoma cell lines increased, primarily localizing into the nucleus similar to glioblastoma tissues. Exposure of glioblastoma cells to vincristine resulted in enrichment of the G₂-M fraction of the cell cycle, which suggests that vincristine-mediated growth inhibition of glioblastoma is correlated with mitotic inhibition. Using doses lower than those found to reduce the viability and proliferation of cells by 50% (IC₅₀), vincristine decreased both the expression of VEGF mRNA and the level of HIF-1α protein in hypoxic glioblastoma cells. In addition, following exposure to vincristine, the expression of VEGF mRNA was correlated with HIF-1α protein levels.

Conclusions: Our results suggest that the mechanism by which vincristine elicits an anti-angiogenic effect in glioblastomas under hypoxic conditions might be mediated, in part, by HIF-1α inhibition.     

脑电图预测痫性发作研究进展

癫痫(epilepsy)是由脑部神经元高度同步化异常放电所致的临床综合征,系神经系统的常见病,困扰着全世界约1%的人群.每次神经元的阵发性放电或短暂的脑功能异常称为痫性发作(seizures).     

Midazolam in treatment of various types of seizures in children

Midazolam is a recently developed water-soluble benzodiazepine that shares anxiolytic, muscle relaxant, hypnotic and anticonvulsant actions with other members of this class. There are limited studies that midazolam can be used successfully to treat seizures in adults and children. In this study, 0.2 mg/kg intramuscular (IM) midazolam was administered to 11 children (eight boys and three girls), aged 3 days to 4 years (mean age 1.8±1.4 years), with seizures of various types. In all but one child, seizures stopped in 15 s–5 min after injection. No side effects were observed. These results suggest that IM administration of midazolam may be useful in a variety of seizures during childhood, especially in case of intravenous (IV) line problem.     

Developmental effects of in vivo and in vitro inhibition of nitric oxide synthase in neurons

The diffusible chemical messenger nitric oxide (NO) is involved in neuronal plasticity and it is, therefore, supposed to play a role in brain development. A shortage of NO during the critical period of brain maturation may theoretically have long-lasting consequences on the organization of the adult brain. We have performed in neonatal rats a chronic inhibition of the enzyme responsible for NO production, nitric oxide synthase (NOS), from postnatal day 3 to postnatal day 23, through administration of the competitive antagonist N-nitro-L-arginine methylester (L-NAME). The calcium-dependent catalytic activity resulted almost completely inhibited throughout the period of treatment and it took more than 4 days after its suspension to get a full recovery. The expression of the neuronal isoform of the enzyme (nNOS), revealed by immunoblotting, was unchanged during the treatment and after it. The histochemical reaction for NADPH diaphorase was reduced at the end of the treatment and recovered in concomitance with the recovery of the catalytic NOS activity. No gross structural alterations were detected in brain morphology. The levels of three neurotransmitter-related and one astrocytic marker were unchanged in the cerebellum, hippocampus and cortex of 60-day-old rats which had been neonatally treated. A similar lack of significant effects on neurochemical brain maturation was also noticed in a parallel series of experiments, in which a short pulse of NOS inhibition was performed at a critical prenatal time of brain development, from gestational day 14 to gestational day 19. In vitro, chronic exposure of cerebellar granule cells to L-NAME (500 microM) resulted in slight decrease of surviving neurons after 8 days in culture and in better resistance to the challenge of stressful culture conditions. The present results suggest that the basic plan of brain organization can be achieved despite an almost complete NOS inhibition during the maturation period. In vitro, NOS inhibition may bring to more pronounced consequences on neuronal viability and function.     

自噬参与帕金森病发病的研究进展

近年来,蛋白质的降解障碍被认为是帕金森病（Parkinson’Sdisease,PD）发病过程中的重要因素,人们已经公认泛素一蛋白酶体系统（ubiquitin--pro—teasomesystem,UPS）功能异常或衰竭能够导致细胞内异常蛋白蓄积、细胞功能障碍,甚至细胞凋亡。与此同时,蛋白降解的另一条途径——自噬-溶酶体途径（autophagy—lysosomepathway,ALP）也已成为了生命科学领域的研究热点,自噬与神经变性疾病,尤其是PD的关系日益受到人们的重视。     

The Burden of Agoraphobia in Worsening Quality of Life in a Community Survey in Italy

ObjectiveCurrent nosology redefined agoraphobia as an autonomous diagnosis distinct from panic disorder. We investigated the lifetime prevalence of agoraphobia, its association with other mental disorders, and its impact on the health-related quality of life (HR-QoL). MethodsCommunity survey in 2,338 randomly selected adult subjects. Participants were interviewed with the Advanced Neuropsychiatric Tools and Assessment Schedule (ANTAS), administered by clinicians. The diagnoses were based on the ICD-10 criteria. The Short-Form Health Survey (SF-12) was used to quantify HR-QoL. ResultsIn the sample, 35 subjects met the criteria for agoraphobia (1.5%), with greater prevalence among women (2.0%) than men (0.9%): odds ratio (OR) 2.23; 95% CI: 1.0-5–2. Agoraphobia was more often seen among those with (n=26; 1.1%) than without (n=9; 0.4%) panic disorder: OR=8.3; 2.9–24.4. Co-morbidity with other mental disorders was substantial. The mean score of SF-12 in people with agoraphobia was 35.2±7.8, with similar levels of HR-QoL in people with (35.3±7.9) or without (34.8±7.3) panic disorder: ANOVA: F(1;33)=0.0; p=1.00. ConclusionOne out of seventy people may suffer from agoraphobia in their lifetime. The attributable burden in terms of HR-QoL is substantial and comparable to the one observed for chronic mental disorders such as major depression, post-traumatic stress disorder, or obsessive-compulsive disorder.