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41.
双歧杆菌的细胞壁成分能有效的激活免疫细胞,促使这些效应细胞释放免疫活性物质,并对多种肿瘤的发生与发展具有一定的抑制作用。本研究利用我室提取的双歧杆菌DNA观察了其对小鼠J774A.1巨噬细胞的活化作用。收集厌氧培养的双歧杆菌(菌种由山东省防疫站提供),加入溶菌酶(1mgm1)与10%SDS(终浓度为1%)裂解菌体,饱和酚抽提去除菌体蛋白,透析,用紫外分光光度计测定所提取的双歧杆菌DNAA260/A280为1.823,经薄板层析证实所制备的双歧杆菌DNA中无脂多糖存在,经HpaⅡ酶酶切证实所制备的双歧杆菌DNA具有一定的非甲基化CpG基序,冷冻干燥后备用… 相似文献
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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. 相似文献
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禁食对蛋鸡肝脏腺苷-磷酸激活的蛋白激酶活性的影响 总被引:4,自引:0,他引:4
腺苷 -磷酸 (AMP)激活的蛋白激酶 (AMP- acti-vated protein kinase,AMPK)是丝氨酸激酶家族的一员 ,由 AMP和其上游激酶 AMPK激酶所活化 ,对细胞内 AMP/ATP的变化非常敏感 [1] ,被称为真核细胞的“代谢感受器”[2 ]。研究发现在跑步 [3 ,4 ]、电刺激肌肉 [5,6]或禁食应激后 [7] ,大鼠肝脏和肌肉中的AMPK活性升高数倍 ,乙酰辅酶 A羧化酶 (ACC)活性显著下降甚至丧失 ,丙二酸单酰辅酶 A产量降低甚至为零 ,脂肪酸合成受抑。同时 ,AMPK活化后 ,脂肪酸的氧化率显著提高 ,CO2 和酮体生成量明显增加[4 ,8] 。这些均表明 ,AMPK活化… 相似文献
46.
肿瘤浸润性淋巴细胞(TIL)经白细胞介素2(IL-2)体外培养后具有很强的体内外抗肿瘤作用,且有一定的靶细胞特异性,其抗肿瘤效果强于淋巴因子激活的杀伤细胞即LAK细胞(P<0.01)。从瘤体中新鲜分离到的TIL对自体肿瘤细胞的杀伤活性极低,经IL-2体外培养后,其杀伤活性逐渐增高,以培养至7~25d的杀伤活性最强,这与IL-2使TIL分泌3种抗癌淋巴因子包括IL-2、IFN-γ、淋巴毒素(LT)增加有关。体外培养25d后,TIL的抗肿瘤活性下降,实验表明这与培养过程中TIL的Lyt-2~+细胞(Tc)减少而L3T4~+细胞(T_H)增多有关。TIL经冻存复苏和IL-2体外培养后仍保持很强的抗肿瘤活性,冻存前后比较未见显著差异(P>0.05),这为间断地运用TIL治疗复发性、晚期肿瘤提供了一条可行的途径。 相似文献
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5—羟色胺介导的血小板激活可能与抑郁症患者发生急性冠脉综合征事件有关 总被引:1,自引:0,他引:1
目前,冠心病和急性冠脉综合征(acute coronary syn-drome,ACS)(包括:不稳定心绞痛、急性心肌梗死和心源性猝死)仍是导致发达国家死亡的主要原因。由于传统的危险因素并不能解释所有的ACS事件,人们正在寻找其他非传统的ACS的危险因素。近年来大量的文献报道,抑郁症患者的ACS事件明显增加,而未发现有传统的危险因素,抑郁症患者发生ACS事件的确切机制不明。 冠状动脉斑块破裂激活血小板,血栓形成是ACS发生的基础,因此想到抑郁症患者也许存在血小板的过度激活,引起ACS事件。神经化学、神经内分泌以及神经解剖的改变参与了抑郁症的发生。抑郁症患者5-羟色胺(5-HT)异常。5-HT是血小板激活的激动剂,通过5-HT2A受体起作用,因此可能参与ACS的发生。Daichi Shimbo等人为验证抑郁症患者是否存在5-HT增高,激活血小板而参与ACS的发生,他们观察了抑郁症患者、非抑郁 相似文献
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Ⅱ型糖尿病血浆PAI-1、t-PA检测的意义和结果评价 总被引:1,自引:1,他引:0
目的:通过对Ⅱ型糖尿病患者分组(伴血管病变组、胰岛素抵抗组、胰岛素抵抗伴血管病变组、Ⅱ型糖尿病组)检测PAI-1、t-PA抗原及活性,并计算抗原比和活性比,以评价各检测指标的临床价值。方法:采用ELISA法检测PAI-1及t-PA抗原,采用发色底物法检测PAl-1、t-PA活性。结果:189例标本总体患病组及分组后各组的PAI-1活性、t-PA活性及t-PA活性/PAI-1活性比值与正常对照组比较均有显著性差异(P<0.05)。患病组间除t-PA抗原,其余检测显示胰岛素抵抗组、胰岛素抵抗组伴血管病变组与Ⅱ型糖尿病组存在显著性差异(P<0.05)。结论:在上述检测指标中t-PA活性、PAI-1活性反映血管病变的发生较敏感,t PA/PAI-1的活性比值更具临床应用价值。 相似文献
50.
目的:通过电镜观察,探讨TNFα和肝星状细胞激活的关系。方法:采用体外培养大鼠HSC,将细胞分为对照组和TNFα组,收集细胞制作电镜标本,在透射电镜下观察HSC的形态学的改变。结果:电镜下见TNFα组细胞体积增大,可见粗面内质网数量明显增多,线粒体、内质网呈轻度扩张,呈明显激活样改变。结论:TNFα对HSC有增殖激活的作用。 相似文献