嗅鞘细胞对脂肪干细胞诱导分化的影响

目的 比较2种不同方法共培养脂肪干细胞后神经元特异性核蛋白(neuron specific nuclear protein,NeuN)的表达.方法 以transwell小室为共培养载体,实验组中将脂肪干细胞接种于上室,嗅鞘细胞接种于下室,对照组下室无嗅鞘细胞,只加入嗅鞘细胞条件培养液,共培养12 d后观察脂肪干细胞NeuN的表达.结果 共培养12 d后2组都有部分脂肪干细胞表达NeuN,实验组NeuN阳性率为303/345(87.8%),而对照组为120/320(37.5%),差异有统计学意义(χ~2=181.6,P＜0.05).结论 脂肪干细胞在与嗅鞘细胞共培养时更容易向神经元样细胞分化.     

Treatable Partial Epilepsy and Unilateral Opercular Neuronal Migration Disorder

Summary: Five patients with treatable partial epilepsy and unilateral opercular neuronal migration disorder (NMD) are reported. Outcome was considered favorable when seizure control was prompt and complete with appropriate antiepileptic drug (AED) therapy, and when there was no relapse after AED discontinuation. Minor cortical sensorimotor defects were noted in 4 patients. All had normal mental status. No epileptic discharges were observed in the EEG of 4 patients, but rolandic spikes were observed in 1. The electroclinical and evolutive features suggested partial idiopathic epilepsy in 2 patients. Cases with focal neuronal migration disorders and favorable epilepsy outcome are probably more common than has been reported previously. The extent and location of the underlying microscopic lesions associated with the radiologically detectable cortical dysplasia may influence clinical outcome.     

书写痉挛患者丘脑腹外侧核团细胞电活动特点

目的 探讨书写痉挛(WC)患者丘脑腹外侧核团(VL)细胞电活动特点,为临床治疗提供可靠的依据.方法 10例WC患者在行立体定向VL毁损术的同时,应用微电极和肌电记录技术采集VL细胞和手术对侧肢体肌电活动.分析不同细胞的放电模式和平均自发放电频率(MSFR),并探讨VL细胞放电活动与肢体肌电的关系.结果 在10个针道中共甄别出85个VL神经元,61.2%的神经元呈不规则放电活动,MSFR为(20.3±14.9)Hz,变异系数(CV)为1.38±0.40;38.8%的神经元为紧张性放电活动,MSFR为(44.4±21.5)Hz,CV为0.84±0.11.功率谱相关性分析发现VL细胞放电活动的改变与WC相关(P＜0.05,n=12).结论 VL参与WC的病理生理过程.     

Oxcarbazepine: Clinical Development Program

Summary: Oxcarbazepine (OCBZ, Trileptal) is registered in several countries and has been well received by patients and physicians. However, newer standards in many other countries require additional data before registration can be achieved. For this reason, Ciba has implemented further clinical studies. OCBZ has a chemical structure that is closely related to carbamazepine (CBZ). In humans, OCBZ is not oxidatively metabolized, therefore causing little, if any, induction of hepatic enzymes. Because of this, and because of low protein-binding properties, OCBZ causes markedly fewer interactions with concomitant medications than most marketed antiepileptic drugs. OCBZ has been shown to have significantly fewer limiting side effects (described as side effects leading to discontinuation of treatment) than CBZ, while showing comparable efficacy. Many patients who are hypersensitive to CBZ can be treated with OCBZ. The usually administered dosage of OCBZ is approximately 50% higher than that of CBZ. However, better tolerability of OCBZ makes it possible to give higher dosages. The plasma concentration half-life of the active metabolite (monohydroxy derivative; MHD) makes it possible to administer OCBZ twice daily. No changes in dosage are necessary in patients with impaired renal function unless creatinine clearance is below 30 ml/ min. In patients with such severely reduced creatinine clearance, the dose of OCBZ should be halved. Specific questions e.g., such as whether OCBZ causes hepatic enzyme induction at higher doses and the effect of OCBZ on intrinsic sex hormones, will be answered in future studies. In addition, the tolerability and pharmacokinetics of OCBZ in specific target populations such as the elderly, children, and hepatically impaired patients will be addressed. This will enable a more complete delineation of the clinical profile of OCBZ, thereby helping physicians to decide how best to use OCBZ in their patients with epilepsy.     

Effects of Carbamazepine on Murine Humoral and Cellular Immune Responses

Summary: Oral administration of carbamazepine (CBZ)(15, 10, or 5 mg/kg) to mice significantly decreased both humoral and cellular immune responses evaluated by enumeration of direct and indirect plaque-forming spleen cells (PFC) and delayed–type hypersensitivity reaction (DTH) against sheep red blood cells (SRBC) as compared with those observed in normal control animals. Moreover, spleen T cells obtained from CBZ–treated donor mice were capable of decreasing both PFC and DTH responses of normal spleen cells transferred into lethally irradiated recipient animals. The immunodepressor effect of CBZ was observed even though administration of CBZ induced augmentation of spleen cellularity.     

强脑因子生物学特性的实验研究

目的 探讨强脑因子对大鼠胎鼠脑神经细胞培养物的生物学保护效应 方法 取16日龄Wistar大鼠脑神经细胞经体外培养后,分别进行(1)组织形态学观察:在神经细胞培养物中加入不同剂量强脑因子(1 10和100mg/L),光学显微镜下观察细胞形态学变化 在电子显微镜下观察神经细胞超微结构变比;(2)神经细胞代谢活性检测:应用四唑盐(tetrazolium,MTT)法测定不同剂量强脑因子对神经细胞代谢活性的影响;(3)可溶性蛋白质水平测定:应用Bradford蛋白定量法测定不同剂量强脑因子对神经细胞胞浆内可溶性蛋白质水平的影响;(4)强脑因子抗神经细胞凋亡试验:应用神经元特异性烯醇化酶(neuron-specific enolase,NSE)定量法,测定强脑因子与奥地利产脑活素对NSE活性表达的影响。结果(1)强脑因子可促进神经细胞分化成熟 突起增多并延长、细胞数量增加。(2)在不同剂量强脑因子作用下 神经细胞MTT代谢率增强,细胞浆内蛋白质水平升高 而且随着强脑因子剂量的增加均呈现出明显的剂量依赖关系;促进NSE表达活性,利于神经母细胞分化(3)强脑因子可增强神经细胞抗缺氧作用及抗谷氨酸所致的细胞凋亡效应 且功效强于奥地利产脑活素 结论 在相同实验条件下,强脑因子对体外培养的神经细胞有生物学保护作用,效果优于脑活素     

Neuronal and glial differentiation within expanded glial cultures derived from the lateral and medial ganglionic eminences

Attached glial-like cell cultures were established from the lateral and medial ganglionic eminences (LGE and MGE) and from the neocortex (Cx) of E13.5 mouse embryos, and expanded over four to five passages under epidermal growth factor (EGF) stimulation. Following removal of EGF and serum, we analysed the generation of neurons and glial cells within the cultures. Significant numbers of betaIII-tubulin-positive neurons were generated in both the LGE (about 7% of total cell numbers) and the MGE (around 2%). However, only few betaIII-tubulin-positive cells with neuronal morphologies were detected in the differentiated Cx cultures. The newly formed neurons were to a large extent GABAergic, and many of the MGE-derived, but not the LGE-derived, cells expressed the MGE-marker NKX2.1. Most cells in all cultures still appeared astroglial-like, expressing glial fibrillary acidic protein (GFAP), but in addition, CNPase-positive cells with oligodendroglial morphologies were present in the MGE (0.68%), and, to a lesser extent (0.2%), in the LGE cultures. The present results demonstrate that cells of expanded glial cultures from both the LGE and MGE can give rise to significant and, to a certain extent, region-specific neuronal and glial cell types under differentiating conditions.     

Electrophysiological characterization of sodium channel types in the HCN-1A human cortical cell line

Electrically evoked sodium currents were recorded under whole-cell patch clamp from undifferentiated HCN-1A cells. Peak sodium currents had a half-maximal activation, V_m0.5, of −22.6 ± 1.0 mV with a voltage dependence, K_m, of 7.28 ± 0.39 mV⁻¹. Steady-state inactivation indicated the presence of two types of sodium channel. One type inactivated with V_h0.5 = −93.8 ± 1.2 mV and k_h = −6.8 ± 0.4 mV⁻¹. The second type of sodium channel inactivated w V_h0.5 = −44.6 ± 1.5 mV and k_h = −7.3 ± 0.4 mV⁻¹. The occurrence of each channel type varied from cell to cell and ranged from 0 to 100% of the total sodium current. No variation in the rate of inactivation was seen when the holding potential was adjusted to eliminate the more negative of the two inactivation components. Application of tetrodotoxin (TTX) or saxitoxin (STX) revealed channel types with two different affinities for each toxin. TTX blocked peak sodium conductance with apparent IC50s of 22 nM and 5.3 μM. STX was more potent, with apparent IC₅₀s of 1.6 nM and 1.2 μM. There was no statistical correlation between toxin sensitivity and steady-state inactivation voltage, suggesting that these properties varied independently among sodium channel types.     

MiRNA-132上调脑源性神经营养因子表达抑制β-淀粉样蛋白诱导的神经元损伤研究

研究背景脑源性神经营养因子(BDNF)在阿尔茨海默病(AD)发病机制中发挥重要作用,微小RNA-132(mi RNA-132)在神经元呈高表达,可以通过调控靶基因表达参与BDNF介导的神经发育过程。本研究旨在探讨阿尔茨海默病神经元模型中mi RNA-132与BDNF的调控关系和神经保护作用。方法体外培养海马神经元72 h后慢病毒转染mi RNA-132,并于体外培养第7天以β-淀粉样蛋白(Aβ)处理制备阿尔茨海默病神经元模型;实时荧光定量聚合酶链反应观察对照组与AD组mi RNA-132表达差异以及不同处理组BDNF m RNA表达变化,噻唑蓝法观察不同处理方式对细胞活性的影响。结果 (1)AD组海马神经元mi RNA-132(t=13.888,P=0.000)和BDNF m RNA(t=-12.274,P=0.000)表达水平均低于对照组。(2)原代培养的海马神经元经慢病毒转染后倒置相差荧光显微镜可见绿色荧光蛋白,对照组(t=16.135,P=0.000)和AD组(t=8.656,P=0.000)转染过表达mi RNA-132后均能上调BDNFm RNA表达。(3)AD组海马神经元活性降低(t=-6.023,P=0.000),AD组转染mi RNA-132后神经元活性增强(t=3.385,P=0.007),予以外源性BDNF共培养后神经元活性明显改善(t=3.672,P=0.004)。结论阿尔茨海默病神经元模型mi RNA-132和BDNF表达水平均下降,mi RNA-132可上调BDNF表达,提示mi RNA-132和BDNF对阿尔茨海默病神经元模型具有神经保护作用,有望为阿尔茨海默病诊断与治疗提供新的视角。