神经调节素对阿尔茨海默病大鼠模型海马细胞凋亡和核转录因子κB表达的影响

目的 研究神经调节素1β( neuregulin 1β,NRG1β)对β-淀粉样蛋白1-40(beta-amyloid protein,Aβ1-40)所致的模拟阿尔茨海默病模型大鼠空间学习记忆能力、神经元凋亡、核转录因子κB( nuclear factor kappa B,NFκB)表达的影响,探讨NRG改善学习记忆能力的作用机制.方法 成年健康雄性Wistar 大鼠30只,随机数字表法分为对照组、模型组和治疗组,每组10只,经侧脑室微量注射Aβ1-40建立实验性阿尔茨海默病模型大鼠,经侧脑室注射NRG1β(0.3μg·kg-1)干预治疗.各组大鼠实验前及造模7d后、治疗14d后均用Y型迷宫检测大鼠学习和记忆功能,利用HE染色观察海马神经细胞的结构变化,原位TUNEL法检测海马神经细胞凋亡,免疫组织化学法检测海马神经细胞NFκB的表达.结果 模型组大鼠学习能力[ (57.50±1.58)次]和记忆能力[(7.20±1.03)次]较对照组学习[(59.50±2.79)次]和记忆能力[(7.50±1.08)次]明显下降(=20.36,5.28,P＜0.05),海马区神经细胞排列稀疏、紊乱,有明显神经元脱失,TUNEL阳性细胞数明显增多、NFκB表达增加(P＜0.05).NRG1β治疗组大鼠学习记忆能力[ (67.70±4.90)次,(5.80±0.63)次]及细胞结构较模型组[(79.10±4.12)次,(4.40±0.69)次]显著改善( t=5.63,4.69,P＜0.05).相对于模型组[(41.10±7.95)次,(29.30±7.24)个],NRG1β治疗组NFκB表达(25.90±6.67)明显减弱、细胞凋亡数量[(23.50±3.89)个]明显减少(t=4.63,2.23,P＜0.05).结论 NRG1β能抑制海马神经细胞NFκB表达,减少细胞凋亡,从而改善阿尔茨海默病大鼠的学习和记忆能力.     

Leukemia inhibitory factor arrests oligodendrocyte death and demyelination in spinal cord injury

As a consequence of secondary pathophysiological mechanisms elicited after spinal cord injury (SCI), oligodendrocytes die by waves of apoptosis. This ultimately results in demyelination of intact axons leading to a loss of their conducting properties. Preservation of as few as 5% to 10% of myelinated axons in individual tracts can confer locomotor recovery. Thus, strategies aimed at rescuing mature oligodendrocytes ensheathing viable axons are likely to be of therapeutic significance. We report that leukemia inhibitory factor (LIF) can prevent oligodendrocyte apoptosis, notably contralateral to the spinal cord lesion, through the induction of the JAK/STAT and Akt signaling pathways as well as by potentiating the expression of the antiapoptotic molecule, cIAP2. Reduced oligodendrocyte apoptosis after SCI with LIF administration resulted in a substantial decrease in demyelination shown by the preservation of lamellated myelin surrounding viable axons and deposition of the degraded myelin basic protein. The data suggest that LIF signals survival in oligodendrocytes after SCI, prevents the secondary wave of demyelination, and thereby reduces inhibitory myelin deposits.     

糖皮质激素反应性与急性淋巴细胞白血病患儿预后的关系

目的评价糖皮质激素反应性与急性淋巴细胞白血病患儿持续缓解、复发、死亡等预后的关系。方法收集中山大学附属第一医院2008年6月至2011年12月146例住院急性淋巴细胞白血病患儿,通过泼尼松诱导试验初步判断激素的反应性,根据激素反应性不同分组并结合相应的实验室指标:初始外周血白细胞数,初始外周血幼稚淋巴细胞数,外周血幼稚淋巴细胞百分比,融合基因MLL及BCR/ABL,化疗后第8、26天骨髓象,从而评价急性淋巴细胞白血病患儿糖皮质激素反应性与预后的关系。结果 146例患儿中,糖皮质激素反应性敏感(PR+)者为121例(82.88%),其中107例(88.43%)处于持续缓解状态,复发11例,死亡2例,放弃治疗1例。糖皮质激素反应性不敏感(PR-)者为25例(17.12%),其中持续缓解13例,复发6例,死亡5例,放弃治疗1例。PR+组复发死亡率明显低于PR-组,其中两组患儿的初始外周血白细胞数、初始外周血幼稚淋巴细胞数、外周血幼稚淋巴细胞百分比、化疗后第8、26天骨髓象、危险度的分级差异有统计学意义,且复发组的初始幼稚淋巴细胞百分比明显高于未复发组。结论通过泼尼松诱导试验结合一系列实验室指标可判断糖皮质激素的反应性,从而指导疾病的治疗和预测疾病转归。     

Eagle syndrome presenting with external carotid artery pseudoaneurysm

Eagle syndrome refers to a clinical syndrome caused by the abnormal elongation of the styloid process with calcification/ossification of the stylohyoid ligament. We present the first reported case of Eagle syndrome resulting in an external carotid artery (ECA) pseudoaneurysm. A patient presented to emergency room with an expanding, painful right-neck mass. CT angiography with three-dimensional volume rendering showed a bilobed 4.0-cm right ECA pseudoaneurysm and bilateral ossification of the stylohyoid ligaments with a sharpened edge of the right styloid process at the level of the carotid artery. Aneurysmectomy was performed, and a common carotid to internal carotid bypass with reversed saphenous vein restored arterial continuity. Local resection of the styloid process with a rotational sternocleidomastoid flap was performed. The pathology report was consistent with a diagnosis of a pseudoaneurysm. A six-month clinical follow-up confirmed the complete resolution of symptoms with no neurological deficits.