胚胎干细胞向神经细胞分化的研究进展

胚胎干细胞(embryonic stem cell,ESC)是由早期胚胎内细胞团或原始生殖细胞经体外分离、抑制分化培养获得的多潜能细胞,具有发育分化的多潜能性和无限的自我更新能力,在一定条件下可定向诱导分化为某种类型细胞。ESC在体外培养扩增6个月以上仍能保持其多能性,可诱导分化为     

表没食子儿茶素没食子酸酚对β-淀粉样多肽损伤的星形胶质细胞的保护作用

目的研究表没食子儿茶素没食子酸酚（EGCG）对异常蛋白β-淀粉样多肽（AB）损伤星形胶质细胞（AS）的保护作用，进一步探讨其作用机理。方法采用原代细胞培养技术，分离培养新生1d大鼠皮质AS，细胞纯化后，加入Aβ进行处理，随后加入不同浓度（0．1、1、5、10、25、50umol／L）的EGCG培养24h，观察细胞的形态学变化；MTT比色法进行细胞活性分析、AS中丙二醛（MDA）以及培养液中乳酸脱氢酶（LDH）含量的变化的检测；比较上述指标在损伤前后的变化。结果EGCG能够减轻Aβ对AS的损伤，抑制AS的MDA的产生，降低AS外液中LDH的含量，增强细胞的活性。结论EGCG能够抑制Aβ对AS的损伤作用，并且对其有神经保护作用，这种保护作用可能与其抑制Aβ引起细胞过度氧化有关。     

有关星形细胞瘤术后生存因素临床分析

本文对手术治疗的38例星形细胞瘤，从临床方面总结讨论如下。 1临床资料 本组共38例，男22例，女16例，年龄在20～64岁之间，其中20～40岁17例、41-60岁16例、60岁以上5例。     

脊髓胶质细胞在小鼠骨癌痛形成中的作用

Objective To evaluate the role of gliocyte in the spinal cord in the development of bone cancer pain (BCP) in mice. Methods Forty male C3H/He mice aged 8-10 weeks weighing 18-22 g were randomly divided into 4 groups ( n = 10 each) : group I sham operation (group S) , group II BCP, group Ⅲ PBS and group IV minocyline (group M) . In group BCP, PBS and M, bone cancer pain was produced by injection of NCTC2472 fibrosarcoma cell suspension (2 x 105 cells) 10 μl into medullary cavity of calcaneus bone, while in group S, PBS solution 10 μl was injected instead of cancer cell suspension. In group PBS and M, PBS 5 μl and minocyline 5 μl (dissolved to 0.2 mmol/L in PBS)_were given IT immediately before cancer cell inoculation once a day for 11 consecutive days respectively. Mechanical pain threshold was measured at 1 d before cancer cell inoculation, and at 0, 3, 5, 7, 9 and 11d after cancer cell inoculation. Cold pain threshold was measured at 3, 7, 9 and 11d after cancer cell inoculation. The animals were killed after measurement of pain threshold and L4-6, segment of spinal cord was removed for determination of GFAP and CD11b expression by Western blot. Results Compared with group S, mechanical pain threshold was significantly increased at 3-11 d after cancer cell inoculation in group BCP and PBS, and at 3 and S d after cancer cell inoculation in group M, and cold pain threshold was significantly increased at 7-11 d after cancer cell inoculation, and expression of CD11b and GFAP was up-regulated in group BCP, PBS and M ( P < 0.05) . Compared with group BCP, mechanical pain threshold was significantly decreased at 3-11 d after cancer cell inoculation, cold pain threshold was significantly decreased at 7-11 d after cancer cell inoculation, and expression of CD11b and GFAP was down-regulated in group M ( P <0.05) . ConclusionThe activiton of gliocyte in the spinal cord is involved in the development of bone cancer pian in mice.     

Holzer改良磷钼酸结晶紫染色法

神经胶质细胞是神经系统特有的组织成分,广泛分布于中枢神经及周围神经中,起着支持组织的作用。在中枢神经系统发生的肿瘤中,神经胶质细胞瘤最多.故神经胶质细胞染色主要用以诊断这类肿瘤。神经胶质细胞用常规 HE 染色,一般只能见到胞核及少许的胞浆,唯有特殊染色才能显示神经胶质细胞的全貌.组织固定:用10％甲醛溶液固定。Holzer 磷钼酸晶紫溶液配制:①0.5％磷钼酸水溶液20ml,95％酒精40ml,临用前将两液混合即可.②结晶紫0.5g,无水酒精2ml.氯仿8ml。此液配制后可长期保存,应注意防止挥发。③无水酒精2ml,氯仿8ml.④溴化钾10g,蒸镏水100ml。③苯胺4ml,氯仿6ml,冰醋酸1滴。操作:     

星形胶质细胞瘤伽玛刀治疗的疗效与影响因素

目的分析星形胶质细胞瘤伽玛刀(γ-刀)治疗的疗效与影响因素.方法回顾性分析48例星形胶质细胞瘤病人的γ-刀治疗结果.以性别、有无普通放疗经过、有无化疗经过、边缘剂量、病灶的平均直径、病变的病理等级、影像学上有无相对较清楚的边界为治疗结果影响因素,判定标准以病灶缩小为有效,采用logistic回归模型,确定多因素条件下治疗结果的影响因素.结果有效32例(66.7%),logistic回归模型分析表明:病理等级和病灶平均直径为与肿瘤控制有关的影响因素.结论γ-刀对星形胶质细胞瘤的治疗有一定的意义.     

成年大鼠神经元和星形胶质细胞细胞周期蛋白依赖性激酶抑制因子表达的差异研究

目的比较研究成年大鼠细胞周期蛋白依赖性激酶抑制因子在神经元和星形胶质细胞的表达差异。方法应用免疫荧光和激光扫描共聚焦显微镜观察成年大鼠生理状态下大脑皮层或海马CA1、CA3、DG区神经元和星形胶质细胞细胞周期蛋白依赖性激酶抑制因子(CDKI)p15Ink4b、p21cipl的表达。结果成年大鼠海马区和大脑皮层的神经元有p15Ink4b和p21cipl的表达,细胞核和细胞浆均有表达,且以胞核为主;星形胶质细胞也有上述细胞周期调控蛋白的表达,便细胞数目较少,并且表达这些指标的星形胶质细胞多聚集在海马区。结论成年大鼠大脑皮层和海马区的神经元和星形胶质细胞均表达p15Ink4b和p21cipl,而其在神经元的表达较星形胶质细胞更为普遍。     

丁酸钠促脑胶质瘤细胞分化作用研究进展

丁酸钠(NaB)是一种短链脂肪酸诱导分化剂,对脑胶质细胞瘤可通过抑制其组蛋白脱乙酰基转移酶,致细胞的基因表达、酶类和信号传导通路发生变化来遏制恶性瘤细胞的增殖,促进分化。同时,与化学疗法或温热疗法联合应用时,可产生协同效应。但由于其血浆中的半衰期较短,使其在临床上的应用受到了一定的影响。丁酸钠将会成为一种有潜力的治疗脑胶质细胞瘤药物。     

脑星形细胞瘤中血管内皮生长因子表达与肿瘤血管形成的关系

目的 研究脑星形细胞肿瘤中血管内皮生长因子(VEGF)蛋白的表达及其与微血管密度(MVD)间的相关性。方法 采用免疫组织化学S—P法检测60例脑星形细胞肿瘤中VEGF蛋白的表达，计数肿瘤MVD，分析其意义及两者间的相关性。结果 VEGF总阳性率为63．3％(36／60例)，其中Ⅱ、Ⅲ、Ⅳ级星形细胞瘤中VEGF阳性率分别为42．1％(8/19例)、71．4％(20／28例)、76．9％(10／13例)。间变性星形细胞瘤和多形性胶质母细胞瘤明显高于弥漫性星形细胞瘤(P＜0．05)；在Ⅱ、Ⅲ、Ⅳ级肿瘤各级别间MVD的差异有显著性(P＜0．05)，而且肿瘤从低度恶性向高度恶性转变过程中，微血管形态由窦状扩张为主变为以芽状和细索状为主，而球状血管丛仅出现在胶质母细胞瘤中。VEGF表达与肿瘤MVD呈正相关(P＜0．05)。结论 联合检测VEGF、MVD可作为判断脑星形细胞瘤恶性潜能的重要生物学指标，同时对了解肿瘤血管形成机制有一定意义。     

Extracellular signal regulated kinases 1/2 signal pathway and responses of astrocytes after diffuse brain injury

BACKGROUND: The treatment of diffuse brain injury during an acute period is focused on relieving degrees of secondary brain injury. Generation and development of pathological changes of secondary brain injury depend on signal conduction, so down-regulating over response of astrocyte through interfering a key link of signal conduction pathway may bring a new thinking for the treatment of diffuse brain injury. OBJECTIVE: To observe the effect of over activity of extracellular signal regulated kinases 1/2 (ERK1/2) signal pathway on the response of astrocyte during an acute period of diffuse brain injury. DESIGN: Completely randomized grouping and controlled animal study. SETTINGS: Department of Neurosurgery, the Third Affiliated Hospital, Nanchang University; Department of Neurosurgery, Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology. MATERIALS: A total of 158 healthy male SD rats, of 11 weeks old, weighing 320–370 g, were provided by Experimental Animal Faulty, Tongji Medical College, Huazhong University of Science and Technology. Rabbit-anti-phosphorylated ERK1/2 (pERK1/2) polyclonal antibody was provided by R&D Company; rabbit-anti-glial fibrillary acidic protein (GFAP) polyclonal antibody, SP immunohistochemical kit and horseradish peroxidase (HRP)-labeled goat-anti-rabbit IgG by Santa Cruz Company; specific inhibitor U0126 of ERK1/2 signal pathway by Alexis Company. METHODS: The experiment was carried out in the Laboratory of Neurosurgery, Union Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology from September 2004 to March 2006. ① Detection of pERK1/2 expression: A total of 110 rats were randomly divided into sham operation group (n =5), model group (n =35), high-dosage U0126 group (n =35) and low-dosage U0126 group (n =35). Rats in the sham operation group were only treated with incision of epicranium and fixation of backup plate, but not hit. Rats in the model group were used to establish diffuse brain injury models based on Marmarou free falling body without drug intervention. Rats in the high- and low-dosage U0126 groups were injected into caudal vein with 0.1 and 0.05 mg/kg U0126, respectively, and then, rats were hit to establish injured models. Every 5 rats were collected from model, high- and low-dosage U0126 groups at 5, 30 minutes, 3, 12, 24, 72 hours and 7 days after diffuse brain injury to detect pERK1/2 expression in cortex of parietal lobe based on Western blot technique. ② Distribution of pERK1/2 and positive GFAP cells in brain tissue: Another 48 rats were randomly divided into sham operation group (n =3), model group (n =15), high-dosage U0126 group (n =15) and low-dosage U0126 group (n =15). The intervention and administration were dealt as the same as those mentioned above. Every 3 rats were collected from model, high- and low-dosage U0126 groups at 30 minutes, 3, 12, 24 and 72 hours after model establishment to observe the distribution of pERK1/2 and postive GFAP cells in brain tissue which was cut from coronal section at Bregma –4.8 mm layer with immunohistochemical staining. MAIN OUTCOME MEASURES: pERK1/2 expression in cortex of parietal lobe and distribution of pERK1/2 and positive GFAP cells in brain tissues. RESULTS: ① pERK1/2 expression: After diffuse brain injury, pERK1/2 expression in cortex of parietal lobe was rapidly increased in the model group, reached at peak at 5 minutes and then decreased gradually. But the expression was still in a high level until the 72nd hour and fallen to the basic level on the 7th day. pERK1/2 level was lower in high- and low-dosage U0126 groups than that in model group at various time points (P < 0.01); meanwhile, pERK1/2 level was lower in high-dosage U0126 group than that in low-dosage U0126 group. The results showed that there was a certain dosage dependence on pERK1/2 expression. ② Distribution of pERK1/2 and positive GFAP cells in brain tissue: Positive expression of pERK1/2 lasted in brain tissue from 30 minutes to 72 hours after diffuse brain injury (P < 0.05). In addition, from 30 minutes to 3 hours, brown-yellow stained cells were mainly distributed in plasma, but rarely in nucleus. A lot of positive cells had tree-like apophysis, which was similar to neurons. With the time passing by, more and more nuclei manifested positive stains; moreover, nuclei mainly manifested positive staining until 24 hours after diffuse brain injury. Immune-positive pERK1/2 cells were widely distributed in brain tissue, especially mainly in binding site between deep cortex and cerebral white matter, and then in hippocampus. In addition, ependymal cell and vascular endothelial cells of choroids plexus also manifested strongly positive staining. As compared with model group, positive cells were decreased gradually in high- and low-dosage U0126 groups. However, number of positive cells was less in high-dosage U0126 group than that in low-dosage U0126 group. CONCLUSION: Diffuse brain injury strongly induces the activity of ERK1/2 signal pathway and response of astrocyte; in addition, U0126 can inhibit response of glial cells during an acute period, and the effect manifests dosage dependence.