阻滞弥漫性脑损伤ERK1/2信号通路对星形胶质细胞反应的作用

目的研究阻滞弥漫性脑损伤急性期ERKI／2信号通路过度激活对星形胶质细胞反应的影响。方法制作大鼠外伤性弥漫性脑损伤模型，打击损伤前30min自尾静脉注射U0126。Westemblot法检测损伤脑皮层pERKl／2表达水平，免疫组化染色法检测pERKl／2和GFAP在损伤脑组织中的表达。结果pERKl／2表达在损伤后迅速、显著升高，5min为表达高峰，其后下降，但直到损伤后72h都有高水平表达，至7d下降至基础水平。损伤后各个时间点，U0126组pERKl／2水平较DBI组明显降低（P〈0．05）。U0126组与DBI组比较，12～72h各时间点GFAP阳性细胞平均光密度值降低（P〈0.05）。结论弥漫性脑损伤诱导了强烈的ERKl／2信号通路激活和星形胶质细胞反应。U0126能够剂量依赖性抑制GFAP的表达，抑制急性期星形胶质细胞反应。     

ERK1/2信号途径对大鼠弥漫性脑创伤后神经细胞凋亡的调控机制

目的 探讨脑创伤后ERK1/2信号调控神经细胞凋亡的分子机制.方法 SD大鼠分为正常对照组、模型组、抑制剂U0126高、低剂量组.Marmarou's法制作弥漫性脑创伤模型.光镜下观察伤后神经细胞形态变化;免疫组化和Western Blot法检测伤后磷酸化ERK1/2水平和Bax表达;TUNEL法检测凋亡细胞.结果 与正常对照组比较,模型组海马区部分神经细胞出现变性坏死和凋亡改变,磷酸化ERK1/2、Bax表达增高,神经细胞凋亡数目增多(P<0.05);U0126治疗后,脑组织形态损伤程度、磷酸化ERK1/2和Bax表达、神经细胞凋亡数目回降,上述变化在U0126高剂量组中更为显著.结论 脑创伤后活化的ERK1/2信号通过调控Bax表达在神经细胞凋亡过程中发挥重要作用.     

细胞外信号调节激酶对大鼠局灶性脑缺血后细胞周期调控的影响

目的 研究脑缺血后细胞外信号调节激酶(ERKs)对细胞周期调控的影响.方法 建立光化学法诱导大鼠局灶性脑缺血模型,分为脑缺血组(对照组及治疗组)和假手术组.治疗组于缺血前30min尾静脉注入U0126溶液,对照组尾静脉注入相同体积不含U0126的DMSO稀释溶液.应用免疫组织荧光化学法观察细胞周期蛋白D1(CyclinD1)和细胞周期蛋白E(CyclinE)阳性细胞表达:免疫印迹(Weaem blot)检测磷酸化ERK1/2(pERK1/2)、CyclinD1和CyclinE的蛋白表达;半定量逆转录-聚合酶链反应(PT-PCR)观察转录因子E2F mRNA的表达.结果 治疗组CyclinD1和CyclinE阳性表达的细胞数较对照组显著减少(P<0.05);缺血对照组pERK1/2蛋白表达显著强于治疗组(P<0.05),4h时间点表达最为明显,12h时间点恢复到基线水平,CyclinD1和CyelinE表达6h开始升高,12h表达最为明显,治疗组较对照组显著减弱(P<0.05);缺血对照组E2F mRNA的表达显著强于治疗组和假手术组(P<0.05),以7d表达最为明显.结论 ERKs在大鼠脑缺血中发挥重要作用,抑制脑缺血引起的ERK1/2磷酸化,可降低细胞周期蛋白CyelinD1、CyclinE和E2F的表达.即ERKs可影响细胞周期的调控.     

吗替麦考酚酯对大鼠弥漫性轴索损伤后脑干胶质细胞激活及硫酸软骨素表达的影响简

目的探讨吗替麦考酚酯（MMF）对大鼠弥漫性轴索损伤（DAD后脑干胶质细胞激活及硫酸软骨素表达的影响。方法将72只DAI后SD大鼠随机分为3组：空白对照组、生理盐水治疗组（NS组）、吗替麦考酚酯治疗组（MMF组）。MMF组腹腔注射MMF（100mg／kg）干预;NS组腹腔注射等量生理盐水;空白对照组只作针扎刺激,不注射任何药物。伤后7、14、28d处死3组大鼠,取大鼠脑干进行巨噬细胞一小胶质细胞质抗原（ED-1）、胶质纤维酸性蛋白（GFAP）和硫酸软骨素（CS）免疫组化染色,检测活化小胶质细胞、活化星形胶质细胞、硫酸软骨素蛋白聚糖,并以累积光密度（IOD）值进行定量评估。结果在伤后不同时间点,MMF组活化小胶质细胞、活化星形胶质细胞、硫酸软骨素蛋白聚糖IOD值均显著低于NS组与空白对照组（P〈0．05）;而Ns组和空白对照组之间无统计学差异（P〉0．05）。结论MMF可抑制大鼠DAI后脑干小胶质细胞和星形胶质细胞激活,还可降低cs表达。     

抑制ERK1/2对大鼠弥漫性脑损伤后细胞凋亡的影响

目的 探讨抑制细胞外信号调节激酶1/2（ERK1/2）对大鼠弥漫性脑损伤（DBI）后脑组织细胞凋亡的影响。方法 按随机数字表法将228只成年SD大鼠随机分为假手术组（n=12）、DBI组（n=72）、阻滞剂组（n=72）、对照组（n=72）,后三组按动物处死时间分为30 min、3 h、24 h、48 h、72 h和7 d六个亚组,每亚组12只。参照Mamarou自由落体方法制作重型DBI模型。阻滞剂组损伤后尾静脉注射ERK1/2特异性阻滞剂U0126（0.05 mg/kg）,对照组注射等量溶剂二甲基亚砜。免疫印迹法法检测脑组织磷酸化ERK1/2（pERK1/2）的表达水平,免疫组化法检测Caspase-3表达,流式细胞术检测细胞凋亡率。结果 伤后30 min,脑组织pERK1/2表达水平显著增高（P<0.05）,并持续高水平表达至72 h,伤后7 d与假手术组无统计学差异（P>0.05）。伤后3 h,脑组织Caspase-3表达水平和细胞凋亡率均明显增高,72 h达到高峰,伤后7 d仍明显高于假手术组（P<0.05）。伤后30 min、3 h、24 h、48 h、72 h和7 d,阻滞剂组脑组织Caspase-3表达水平和细胞凋亡率均明显低于DBI组和对照组（P<0.05）,而DBI组和对照组均无统计学差异（P>0.05）。结论 阻滞ERK1/2通路,可显著抑制DBI大鼠脑组织Caspase-3的表达,降低细胞凋亡率。     

肺炎链球菌溶血素致脑损伤中细胞凋亡及凋亡诱导因子的变化及意义

目的 探讨肺炎链球菌溶血素(PLY)致感染性脑损伤中细胞凋亡及凋亡诱导因子(AIF)的表达及意义. 方法 SD大鼠80只按随机数字表法分为PLY组[颈内动脉注射0.2 mL(7μg) PLY]和生理盐水(NS)组(颈内动脉注射等体积NS),每组40只.每组按观察时间点分为6h、12h、24 h、48 h4个亚组,每亚组10只,其中5只注射髓,甲酰胺法测定脑组织EB含量判断血脑屏障(BBB)的破坏程度.5只不注射EB,取脑组织切片,应用免疫组化和TUNEL染色分别检测脑组织神经元特异性烯醇化酶(NSE)、胶质纤维酸性蛋白(GFAP)、AIF蛋白含量和细胞凋亡. 结果 与NS组比较,造模后各时间点PLY组大鼠脑组织EB、NSE、GFAP、AIF蛋白含量均较高,细胞凋亡较多,差异均有统计学意义(P＜0.05); PLY组大鼠脑组织凋亡细胞数与AIF蛋白的表达呈正相关关系(r=0.959,P=0.000). 结论 细胞凋亡参与了PLY诱导的脑损伤的发展过程,AIF可能介导了神经细胞的凋亡.     

Endogenous neurogenesis and neovascularization in the neocortex of the rat after focal cerebral ischemia

The present study was designed to examine whether endogenous neurogenesis and neovascularization occur in the neocortex of the ischemic rat brain after unilateral middle cerebral artery occlusion (MCAO). Sprague-Dawley rats were divided into six groups (n = 29): one control group (n = 4) and five groups composed of animals sacrificed at increasing times post-MCAO (2 days and 1, 2, 4, and 8 weeks; n = 5 per group). To determine the presence of neurogenesis and neovascularization in the ischemic brain, nestin, Tuj1, NeuN, GFAP, Tie2, RECA, and 5-bromo-2'-deoxyuridine (BrdU) were analyzed immunohistochemically. In addition, nestin, GFAP, and Tie2 expression was determined by Western blotting. Triple-labeling of nestin, BrdU, and laminin was performed to visualize the interaction between endogenous neurogenesis and neovascularization. The number of BrdU- and nestin-colabeled cells increased markedly in the neocortex and border zone of the ischemic area up to 1 week after MCAO and decreased thereafter. Western blot analysis revealed that the expression of nestin, Tie-2, and GFAP was amplified in the ipsilateral hemisphere 2 days after MCAO and peaked 1 week after MCAO, compared with that in the normal brain. After ischemic injury, nestin- and BrdU-colabeled cells were observed in the vicinity of the endothelial cells lining cerebral vessels in the ipsilateral neocortex of the ischemic brain. Endogenous neurogenesis and neovascularization were substantially activated and occurred in close proximity to one other in the ipsilateral neocortex of the ischemic rat brain.     

细胞外信号调节激酶在蛛网膜下腔出血损伤中的作用及意义

目的研究细胞外信号调节激酶(ERK)途径在蛛网膜下腔出血(SAH)脑损伤中的作用。方法ICR小鼠随机分为假手术组、模型组、U0126干预组,采用非开颅血管内穿线法制备小鼠SAH模型,给予ERK抑制剂U0126,术后行颅底检查,分别在SAH后12、24、48h 3个时相点取右侧大脑动脉标本,在光镜下观察大脑中动脉病理变化,应用免疫印迹法检测各组p-ERK1/2、caspase-8蛋白表达,TUNEL法检测大脑中动脉内皮细胞凋亡。结果随损伤时间延长,模型组小鼠p-ERK1/2、caspase-8蛋白均有不同程度增强,凋亡细胞增多。与模型组比较,U0126干预组小鼠各时相点3项指标的表达均不同程度下调。结论 ERK信号途径参与小鼠SAH病理损伤过程,并在神经细胞凋亡进程中发挥关键作用。     

骨髓间充质干细胞旁分泌作用与脑缺血后的细胞凋亡*

背景：骨髓间充质干细胞移植治疗脑缺血的机制之一是骨髓间充质干细胞的旁分泌作用,而目前对于这一机制的研究报道较少。 目的：观察骨髓间充质干细胞旁分泌作用对脑缺血后细胞凋亡的抑制作用并探索相关机制。 方法：体外培养大鼠骨髓间充质干细胞,建立大鼠大脑中动脉缺血模型。24只SD大鼠随机数字表法分为4组,每组6只。细胞移植给药组：大鼠纹状体内移植骨髓间充质干细胞后给予ERK1/2抑制剂U0126;非移植给药组：注射等量的PBS后给予U0126;细胞移植对照组：移植骨髓间充质干细胞后给予溶剂对照;非移植对照组：注射等量的PBS后给予溶剂对照。7 d后通过Western blot检测血管内皮细胞生长因子、磷酸化ERK1/2蛋白的表达;TUNEL染色检测梗死区周围及皮质区细胞凋亡情况。 结果与结论：细胞移植组较非移植组大鼠纹状体内血管内皮细胞生长因子蛋白的表达明显增高,磷酸化ERK1/2表达增强,细胞凋亡数明显减少;经U0126处理后,血管内皮细胞生长因子的表达没有变化,而随着磷酸化ERK1/2的表达受到抑制,细胞凋亡数明显增高。提示骨髓间充质干细胞在大脑纹状体内可以旁分泌血管内皮细胞生长因子,并通过激活ERK1/2抑制了脑梗死区细胞的凋亡。     

颅脑损伤大鼠肠道防御素-5 mRNA表达

目的探讨弥漫性脑损伤后肠道防御素-5（RD-5）变化。方法大鼠32只，分为对照组8只；弥漫性脑损伤组24只，再分成3个亚组（24h，3d，7d）。观察回肠RD-5mRNA的表达，回肠肠粘膜的病理改变以及血液内毒素的变化。结果弥漫性脑损伤后24hRD-5 mRNA的表达显著升高（P〈0．01），伤后3d降低至正常水平以下；回肠肠粘膜损伤，血液内毒素伤后24h最高（P〈0．01），3至7d仍显著高于正常水平（P〈0．01）。结论弥漫性脑损伤早期RD-5 mRNA的表达增强可能是机体的一种保护性反应。     

Statin Pretreatment Might Be Associated with Decreased Myocardial Injury After Ischemic Stroke

Background: Myocardial injury is a complication of stroke associated with unfavorable outcome, with the elevation of cardiac troponin as the most sensitive marker. In this study, we aimed at investigating the association between statin pretreatment and poststroke myocardial injury. Methods: Six hundred seventy-one patients diagnosed as acute ischemic stroke were enrolled. According to the histories of statin pretreatment before stroke, patients were categorized into nonstatin (n = 474) and statin groups (n = 197), with the latter further divided into low-dosage, standard-dosage, and high-dosage subgroups according the dosages of statins. The level of troponin-T was tested and troponin-T level ≥14 ng/l was identified to indicate the presence of myocardial injury. The level of troponin-T and the prevalence of myocardial injury was compared between groups. Logistic regression was used to identify the effect of statin pretreatment for the presence of post-stroke myocardial injury. Results: Statin users had lower levels of troponin-T after stroke, with the level of troponin-T being the lowest in the high-dosage subgroup. The results of logistic regression showed that statin pretreatment and high-dosage statin were independent protective factors for the elevation of troponin-T levels. Conclusions: Statin pretreatment might be associated with the decreased myocardial injury after ischemic stroke.     

Effect of extracellular signal-regulated kinase and nitric oxide on compressive neuralgia formation and maintenance

BACKGROUND: Previous studies have shown that extracellular signal-regulated kinase 1/2 (ERK1/2) and nitric oxide activation play a pivotal role in central sensitization and long-term neuronal plasticity induced by noxious stimulation. However, their effects on compressive neuralgia formation and maintenance remain poorly understood.OBJECTIVE: To investigate effects of the specific inhibitor of ERK1/2 signal pathway U0126 on neuronal nitric oxide synthase (nNOS) expression in the dorsal horn of the spinal cord in a compressive neuralgia rat model.DESIGN, TIME AND SETTING: A randomized, controlled experiment was performed at the Institute of Otolaryngology, Head and Neck Surgery, First Hospital of Jilin University from July 2008 to March 2009.MATERIALS: U0126 (Bio-Mol, USA) was used in this study.METHODS: A total of 84 rats were randomly assigned to two groups. In the first part of the experiment, 24 rats were used for behavioral testing, and they were randomly assigned to three sub-groups (n =8): U0126, dimethyl sulfoxide (DMSO) and model control. In the second part of the experiment, 60 rats were used for immunofluorescence and Western blot analysis, and they were randomly assigned to six sub-groups (n = 10): sham surgery, model control, U0126 post-injection at 0.5, 2, 12 and 24 hours. Neuropathic pain was produced by chronic compression to the dorsal root ganglion in rats from each sub-group. Rats in the U0126 group were administered a 5-ug U0126 intrathecal injection, and rats in the DMSO group were administered a 10-μL 5% DMSO intrathecal injection.MAIN OUTCOME MEASURES: Changes in mechanical and thermal hyperalgesia were observed using von Frey filaments and thermalqia stimular. Thermal and mechanical hyperalgesia were stimulated at different time points following intrathecal injection of U0126. nNOS activation and expression in the spinal cord dorsal horn were determined by immunofluorescence and Western blot analysis.RESULTS: Intrathecal injection of U0126 significantly attenuated chronic compression of dorsal root ganglion-induced mechanical and thermal hyperalgesia. Immunofluorescence staining results demonstrated that, compared to the sham surgery group, the number of nNOS-positive neurons was significantly increased in the injured spinal dorsal horn in the model control group (P＜0.01). However, compared to the model control group, there were significantly decreasing numbers of nNOS-positive neurons in the U0126 post-injection groups at 0.5-hour, 2-hour, and 12-hour (P＜0.05). Western blot analysis revealed similar results. CONCLUSION: Decreased activity in the ERK signal pathway resulted in down regulated nNOS expression in the dorsal horn of the spinal cord. These results suggested that ERK is involved in nitric oxide reaction to neuropathic pain.     

Temporal characterisation of pro- and anti-apoptotic mechanisms following diffuse traumatic brain injury in rats.

Few studies have characterised apoptosis in a brain injury model that causes a significant degree of diffuse axonal injury. Such characterisation is essential from a clinical viewpoint since diffuse axonal injury is a major component of human head injury. The present study therefore, examines the expression of active and proactive caspase-3, and the bax, bcl-2 and bcl-x members of the bcl-2 family, to characterise the temporal profile of apoptosis in a model of traumatic brain injury in rats that produces significant diffuse axonal injury. Pentobarbital anaesthetised male Sprague-Dawley rats were injured using the 2m impact-acceleration model of diffuse traumatic brain injury. After injury, diffuse trauma resulted in an increased bax expression followed by induction of caspase-3. The increase in caspase-3 was simultaneous with an increase in anti-apoptotic bcl-2 expression. Bcl-x levels were increased after induction of caspase-3 and the increased levels of bcl-x were sustained to the end of the 5-day observation period. Increased active caspase-3 expression was associated with the appearance of TUNEL positive cells. These cells were detected in different brain regions at different times, with some regions showing no apoptotic cells until 3 days after injury. No TUNEL positive cells were detected at 7 and 14 days after injury. DNA electrophoresis confirmed that DNA fragmentation was maximal at 3 days after injury. Increased active caspase-3 levels were also significantly correlated with increased bcl-2 levels (r=0.80; P<0.001) suggesting that the apoptotic cascade after diffuse traumatic brain injury is a carefully controlled cellular homeostatic response. Pharmacological manipulation of this balance may offer a therapeutic approach for preventing cell death and improving outcome after diffuse traumatic brain injury.     

ERK对缺血缺氧性脑损伤后神经元凋亡的影响

目的研究在缺血缺氧性脑损伤后细胞外信号调节激酶(ERKs)对神经元凋亡的影响。方法建立光化学法诱导大鼠局灶性脑缺血模型,随机分为脑缺血组(缺血组和干预组)和假手术组,干预组于缺血前30min尾静脉注入U0126溶液,缺血组尾静脉注入相同体积不含U0126的DMSO稀释溶液;2,3,5-氯化(或溴化)三苯四氮唑(TTC)染色显示梗死灶;应用免疫组织荧光化学法检测梗死灶周围神经元核心抗原(NeuN)的表达及通过TUNEL方法检测神经元凋亡,并做NeuN与TUNEL的双标;用免疫印迹(Westernblot)方法观察损伤侧皮层NeuN、细胞周期蛋白D1(CyclinD1)和细胞周期蛋白E(CyclinE)蛋白的表达。结果缺血组的梗死体积明显大于干预组,在假手术组未见梗死灶;缺血组大鼠NeuN阳性细胞数和NeuN蛋白表达明显少于假手术组,TUNEL阳性细胞数和CyclinD1和CyclinE蛋白表达明显高于假手术组(P<0.05)。干预组NeuN阳性细胞数和NeuN蛋白表达亦少于假手术组,但多于缺血组,TUNEL阳性细胞数和CyclinD1及CyclinE蛋白表达亦多于假手术组,但少于缺血组(P<0.05)。结论ERK可通过对细胞周期的调控而对神经元凋亡产生影响,抑制脑缺血引起的pERK1/2磷酸化可部分抑制神经元凋亡,减少缺血梗死灶,对缺血性脑损伤起一定的保护作用。     

大鼠正常脑组织伽玛刀照射后GFAP表达的实验研究

目的研究伽玛刀（Gamma knife）立体定向放射外科照射大鼠正常脑组织后亚急性期胶原纤维酸性蛋白（GFAP）的表达随时间的变化，探讨星形胶质细胞（AS）的增殖与放射损伤的关系。方法30只成年雌性Wistar大鼠，随机分为6组，每组5只。其中1组为假照射组，其余5组行伽玛刀照射。运用Leksell 23004B型伽玛刀4mm准直器以50Gy照射大鼠右侧尾壳核。不同组别的大鼠分别在照射后1、2、4、8、12周深度麻醉下断头取出脑组织，行免疫组织化学染色观察GFAP的表达。结果照射后4周靶区内GFAP阳性细胞数目开始增多，细胞形态变得不规则。至8周时GFAP阳性细胞进一步增多，胞体变大，胞浆染色较深。照射后12周GFAP阳性细胞数目最多，胞体明显肥大，形态各异，细胞突起粗大不规则，胞浆呈深棕色。结论伽玛刀放射外科以50Gy照射大鼠单侧尾壳核后，照射靶区GFAP阳性细胞数不断增加，细胞形态肥大、形状不规则。     

Brain injury due to acute organophosphate poisoning Magnetic resonance imaging manifestation and pathological characteristics

BACKGROUND: Acute organophosphate poisoning can cause injuries of multiple visceras; especially, central nervous system injury can increase risk factors of patients with severe acute organophosphate poisoning. An application of modern image may increase diagnostic rate of brain injury in an earlier period and provide evidences for clinical treatment. OBJECTIVE: To reveal imaging manifestations, pathological characteristics and multi-ways injured mechanism of brain injury due to acute organophosphate poisoning. DESIGN: Contrast observational study. SETTING: Department of Medical Image, the Second Hospital of Hebei Medical University. MATERIALS: The experiment was carried out in the Department of Nerve Molecule Imaging Medicine and Laboratory of Neurology, the Second Hospital of Hebei Medical University from August 2003 to February 2004. A total of 30 healthy cats weighing 2.8–3.5 g and of both genders were selected from Animal Experimental Center of Hebei Medical University. METHODS: Thirty healthy cats were randomly divided into control group (n =5) and intoxication group (n =25). Cats in the control group were subcutaneously injected with 0.3 mL/kg saline at four points; while, cats in the intoxication group were subcutaneously injected with 400 g/L 0.3 mL/kg O,O-dimethyl-S-(methoxycarbonylmethyl) thiophosphate at four points. Two minutes after intoxication, cats received muscular injection with 0.5 mg/kg atropine sulfate, and then, brain tissues were collected from parietal lobe, basal ganglia, hippocampus, cerebellum and brain stem were observed at 3, 6, 24 hours, 3 and 7 days after intoxication respectively under optic microscope and electron microscope and expressions of acetylcholinesterase (AChE), choline acetyltransferase (ChAT), glial fibrillary acidic protein (GFAP), glutamic acid (Glu) and γ-amino butyric acid after immunohistochemical staining. MAIN OUTCOME MEASURES: Results of MRI examinations; histological changes under optic microscope and electron microscope; expressions of AChE, ChAT, GFAP, Glu and γ-amino butyric acid after immunohistochemical staining. RESULTS: All 30 healthy cats were involved in the final analysis. ① Imaging and pathological observation: Image manifestations of brain injury induced by acute organophosphate poisoning showed as cerebral edema and symmetry signal abnormality of bilateral basal ganglia; while, pathological manifestations also showed as cerebral edema. ② Observation of immunohistochemical staining: As compared with the control group, after organophosphate poisoning, area of AChE immune-positive cells was decreased obviously (P < 0.01), but area of ChAT immune-positive cells was not changed (P > 0.05); in addition, positive cells of GFAP were increased remarkably (P < 0.01), positive cells of γ-amino butyric acid in cerebral cortex were increased obviously (P < 0.05), but numbers of positive cells of Glu were not changed (P < 0.05). CONCLUSION: Multi-ways injured mechanism invovled in acute organophosphate poisoning. An application of modern image can increase diagnostic rate of brain injury in an earlier period and provide evidences for clinical treatment.     

大鼠液压脑损伤后bcl-2和bax基因的表达分布

目的观察脑损伤后凋亡相关基因bcl-2、bax在脑组织中的表达特点。方法SD大鼠12只,随机分为假手术组(n=4)和液压打击脑损伤组(n=8)。采用侧方液压打击制作颅脑损伤模型,应用免疫组化和原位杂交法及计算机显微图像分析技术,观察SD大鼠脑损伤后12h脑内bcl-2、bax蛋白和mRNA阳性细胞的分布。结果侧方液压打击伤后,bcl-2、bax基因在损伤侧大脑皮质、海马表达明显增强,挫裂伤组织内血肿周边的bcl-2、bax基因表达亦明显增强,阳性细胞表达强度受打击能量和颅内血肿影响而呈梯度分布。结论大鼠侧方液压脑损伤后,bcl-2和bax基因表达受打击能量和颅内血肿的影响,由高到低逐渐递减。这一现象为认识脑损伤后迟发性神经元死亡提供了帮助。     

Analysis of cerebrospinal fluid glial fibrillary acidic protein after seizures in children

PURPOSE: To evaluate pediatric seizure patients for astrocytic injury by measuring cerebrospinal fluid (CSF) glial fibrillary acidic protein (GFAP), determine risk factors for GFAP elevation after seizures, and compare seizure-induced astrocyte injury with neuronal injury by concurrent measurement of CSF neuron-specific enolase (NSE). METHODS: CSF obtained from pediatric patients (n = 52) within 24 h of seizure was assayed for GFAP and NSE. Retrospective chart review was performed for seizure type, duration, and etiology. RESULTS: Overall, children with seizures had elevated CSF GFAP compared with controls (p = 0.0075), but no elevation of NSE (p = 0.1437). No effect of seizure type or etiology was found, but a significant positive effect of seizure duration (p = 0.0010) and status epilepticus (p = 0.0296) was seen on CSF GFAP. Individually, seven children (13%) had elevated GFAP (>440 pg/ml); in five children, the increased GFAP was not accompanied by elevations in NSE (<12 ng/ml). Five children with elevated GFAP had symptomatic etiologies for their seizures, but the etiology of one child with elevated GFAP was cryptogenic, and one had febrile seizures. CONCLUSIONS: Elevation of CSF GFAP after seizures suggests that astrocytic injury may occur in a subgroup of children, primarily in the context of prolonged seizures and symptomatic etiologies. Increased GFAP levels may occur in patients with normal NSE, suggesting that GFAP may be a more sensitive marker of brain injury in some cases.     

脂膜微囊趋向于鼠脑创伤区聚集机制的实验研究

目的研究脂膜微囊向脑损伤位点靶向性聚集的特点，探讨其向鼠脑损伤区靶向性聚集的机制。方法建立脑损伤动物实验模型，制备脂膜微囊悬液。将脑损伤模型建立成功的28只大鼠随机分为以下几组，损伤当日组、伤后24h组、48h组、72h组、7d组、10d组、14d组、21d组、28d组；分别于损伤后不同时间，由尾静脉注射脂膜微囊悬液，鼠脑标本用油红O染色，研究脂膜微囊在脑损伤后的不同时间在损伤灶周围聚集的特点，并采用双重免疫组化染色，研究增生细胞核抗原（PCNA）及胶原纤维酸性蛋白（GFAP）阳性细胞在损伤灶周围分布的特点，讨论其与脂膜微囊靶向性聚集的关系。结果早期即可在损伤灶周围及损伤灶中发现脂膜微囊，且脂膜微囊密度逐渐增加，48h后可在损伤区的周围发现有微囊以丛集方式聚集；在病损10d左右，微囊的密度最大并聚集成环状。损伤后的第2—3周微囊密度下降至一稳定的水平；GFAP，PCNA双重染色发现了它们各自的密度变化曲线，均在损伤后48h达高峰；GFAP阳性细胞的数量及分布范围远较PCNA范围大，且二者均阳性的细胞数量很少。结论脂膜微囊可靶向性聚集于脑损伤位点周围，不同的时间点微囊的密度不同，损伤后第10天其密度达高峰，脂膜微囊靶向性聚集的机制复杂，与血脑屏障破坏引起的血源性细胞渗出有关，也与反应性星形细胞有关。     

高海拔地区骨髓源神经干细胞及BDNF联合移植对大鼠缺血再灌注模型的治疗

目的 探讨高海拔地区大鼠骨髓源神经干细胞(bone marrow mesenchymal stem cells-derived neural stem cells,BMSCs-NSCs)及脑源性神经生长因子(Brain-derived neurotrophic factor,BDNF)联合移植对大鼠脑缺血再灌注模型的疗效及其相关机理。方法 60只Wistar雄性大鼠,置西宁地区正常饲养,制备大鼠脑缺血-再灌注损伤模型; 模型制备完毕后立体定向下进行细胞移植治疗,将大鼠分为3组,即A组:大鼠骨髓源性神经球组(BMSCs-NSCs组,n=20); B组:大鼠骨髓源性神经球联合BDNF组(BMSCs-NSCs+BDNF组,n=20),注射大鼠骨髓源性神经球细胞的同时,联合注射100 ng BNDF; C组:对照组(仅注射DMEM/F12培养基,n=20); 术后对其神经功能进行评定,并于术后24 d取脑组织,行Nestin、GFAP、Map2免疫荧光检测。结果 细胞移植后第3 d,各组间神经功能评分无显著性差异; 细胞移植后第14 d BMSCs-NSCs+BDNF组神经功能评分显著优于BMSCs-NSCs组,BMSCs-NSCs组优于对照组; 免疫组化检测发现,BMSCs-NSCS+BDNF组Nestin、GFAP、Map2的IOD值均显著高于BMSCs-NSCs组; BMSCs-NSCs+BDNF组、BMSCs-NSCs组各检测指标水平均高于对照组; Nestin、GFAP、Map2的表达主要集聚于脑梗死灶与正常脑组织交界处。结论 在西宁地区联合移植大鼠骨髓源神经干细胞及BDNF可显著促进大鼠大脑中动脉闭塞再灌注损伤模型的神经功能恢复。