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971.
972.
The therapeutic potential of bone marrow-derived mesenchymal stem cells (BM-MSCs) has recently been explored in various pathological conditions of the central nervous system (CNS). However, the application of BM-MSCs in acutely induced Alzheimer's disease (AD) has not yet been reported. Herein the feasibility of using the BM-MSCs, as a therapeutic agent for AD has been tested. To assess this possibility, an acutely induced AD model induced by injecting amyloid-β (Aβ) into the dentate gyrus (DG) of hippocampus of C57BL/6 mice was used. Intracerebral transplantation of BM-MSCs into the brain of an induced AD model reduced their Aβ levels when compared to sham-transplanted animals. The diminution of Aβ deposits was accompanied by the activation of microglia. In addition, the activated microglia was located near the Aβ deposits, and their morphology was changed from ramified to ameboid as a sign of microglial phagocytosis. This study provides evidence that BM-MSCs can promote the reduction of Aβ through the microglial activation in this acutely induced AD brain, suggesting a potential therapeutic agent against AD. 相似文献
973.
974.
目的 探究miR-30a-3p与NOD1的靶向关系,及其对心肌细胞缺氧复氧损伤的影响和机制。 方法 将细胞分为Ctrl组、H/R组、miR-30a-3p mimic组和miR-30a-3p inhibitor组,经过缺氧复氧处理后,转染相应的miRNA处理细胞,RT-PCR检测miR-30a-3p和NOD1基因表达水平,荧光素酶报告检测miR-30a-3p和NOD1靶向关系,Western blot检测NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平,CCK8法检测细胞活性,Hoechst检测细胞凋亡,试剂盒检测LDH、CK、MDA、T-SOD水平。 结果 miR-30a-3p表达水平随缺氧复氧处理时间增长而下降,NOD1基因表达水平随缺氧复氧处理时间增长而升高。在荧光素酶报告实验中,NOD1 WT+miR-30a-3p mimic荧光素酶活性显著低于NOD1 WT+NC组。与Ctrl组比较,H/R组miR-30a-3p基因表达水平、细胞活性、T-SOD水平降低,NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平、LDH、CK、MDA水平、细胞凋亡率升高;与H/R组比较,miR-30a-3p mimic组miR-30a-3p基因表达水平、细胞活性、T-SOD水平升高,NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平、LDH、CK、MDA水平、细胞凋亡率降低,miR-30a-3p inhibitor组miR-30a-3p基因表达水平、细胞活性、T-SOD水平降低,NOD1、p-RPI2、p38 MAPK、NF-κB(p65)、cl-caspase-3蛋白表达水平、LDH、CK、MDA水平、细胞凋亡率升高。 结论 miR-30a-3p可靶向作用于NOD1,缓解心肌细胞缺氧复氧造成的损伤,其作用机制可能与调控NF-κB信号通路有关。 相似文献
975.
Sangkyu Son Joonsik Moon Hyungoo Kang YeeJoon Kim Joonyeol Lee 《Human brain mapping》2021,42(13):4336
A small physical change in the eye influences the entire neural information process along the visual pathway, causing perceptual errors and behavioral changes. Astigmatism, a refractive error in which visual images do not evenly focus on the retina, modulates visual perception, and the accompanying neural processes in the brain. However, studies on the neural representation of visual stimuli in astigmatism are scarce. We investigated the relationship between retinal input distortions and neural bias in astigmatism and how modulated neural information causes a perceptual error. We induced astigmatism by placing a cylindrical lens on the dominant eye of human participants, while they reported the orientations of the presented Gabor patches. The simultaneously recorded electroencephalogram activity revealed that stimulus orientation information estimated from the multivariate electroencephalogram activity was biased away from the neural representation of the astigmatic axis and predictive of behavioral bias. The representational neural dynamics underlying the perceptual error revealed the temporal state transition; it was transiently dynamic and unstable (approximately 350 ms from stimulus onset) that soon stabilized. The biased stimulus orientation information represented by the spatially distributed electroencephalogram activity mediated the distorted retinal images and biased orientation perception in induced astigmatism. 相似文献
976.
María Sol Brassesco Elvis Terci Valera Luciano Neder Angel Mauricio Castro‐Gamero Fábio Morato De Oliveira Antonio Carlos Santos Carlos Alberto Scrideli Ricardo Santos Oliveira Hélio Rubens Machado Luiz Gonzaga Tone 《Neuropathology》2009,29(5):585-590
Meningiomas are recognized as the most common late complication following radiotherapy. However, cytogenetic studies in childhood atypical radiation‐induced meningioma are sporadic, mainly because this condition generally occurs after a long latent period. In the present study we show the results of conventional and molecular cytogenetics in a 14‐year‐old boy with a secondary atypical meningioma. Apart from numerical changes, we found complex aberrations with the participation of chromosomes 1, 6 and 12. The invariable presence of loss of 1p was demonstrated by fluorescent in situ hybridization (FISH) analysis with probes directed to telomeric regions and by comparative genome hybridization (CGH). Previous cytogenetic studies on adult spontaneous and radiation‐associated meningiomas showed loss of chromosome 22 as the most frequent change, followed by loss of the short arm of chromosome 1. To the best of our knowledge this is the first report of highly complex chromosome aberrations in the pediatric setting of meningioma. 相似文献
977.
BACKGROUND: Previous studies have demonstrated that brain-derived neurotrophic factor (BDNF) promotes neural differentiation. However, the mechanisms involved in cell cycle-related protein regulation, which highly correlates to neural proliferation and apoptosis, remain poorly understood. OBJECTIVE: To investigate the effects of various concentrations of BDNF on cycle-related protein mRNA expression in induce-differentiated SH-SY5Y cells in vitro prior to and following G2 phase, and to analyze the neuroprotective effects of BDNF. DESIGN, TIME AND SETTING: A comparison, observational study, based on cell biology, was performed at the Department of Biochemistry, Medical College of Tongji University, from March 2005 to October 2006. MATERIALS: SH-SY5Y cells were provided by Shanghai Institute of Cytology, Chinese Academy of Science; BDNF by Alomone Labs, Israel; all-trans retinoic acid (ATRA) by Sigma-Aldrich, USA. METHODS: SH-SY5Y cells were randomly divided into three groups: blank control [cells were treated in Insulin-Transferrin-Selenium (ITS) solution for 7 days], ATRA (cells were treated with ITS solution containing 10 μmol/L ATRA for 7 days), and BDNF (cells were treated identical to the ATRA group for 5 days, and then respectively treated in ITS solution containing 1, 10, and 100 μg/L BDNF for 2 days). The experiment was repeated three times for each group. MAIN OUTCOME MEASURES: mRNA expression levels of cyclin A1, B1, B2, cyclin-dependent kinase 1, and 5 were detected using quantitative real-time RT-PCR; percentage of cells in G1, S, and G2 phases were detected using fluorescence-activated cell sorting. RESULTS: mRNA expression levels of cyclin A1 in the high-dose BDNF group was significantly less than the ATRA group (P 〈 0.05).mRNA expression levels of cyclin B1 was significantly less in the different BDNF concentration groups compared with the control and ATRA groups (P 〈 0.05 or P 〈 0.01). mRNA expression levels of cyclin B2 and cyclin-dependent kinase 1 were significantly decreased in the high-dose BDNF group (P 〈 0.05 or P 〈 0.01). Cyclin-dependent kinase 5 mRNA expression was significantly greater in the low-dose and moderate-dose BDNF groups compared with the ATRA group (P 〈 0.05). The percentage of cells in G1 phase was significantly greater in the different BDNF concentration groups compared with the ATRA and control groups (P 〈 0.01). Moreover, the percentage of cells in S phase was significantly less in the three BDNF groups compared with the ATRA group (P 〈 0.01). However, the percentage of cells in S phase was significantly less in the low-dose and high-dose BDNF groups compared with the control group (P 〈 0.01). CONCLUSION: BDNF enhanced the percentage of cells in G1 phase, but did not alter mRNA expression of cell cycle-related proteins prior to or following G2 phase. These results suggested that BDNF was not a risk factor for inducing apoptosis. 相似文献
978.
目的比较视知觉学习治疗顺、逆规散光性儿童弱视患者(perceptual learning)的疗效。方法将138例(274眼)8-13岁的顺、逆规散光性儿童弱视患者行视知觉学习治疗,观察2年后对其结果进行统计学分析。结果8—13岁的顺规散光造成重度弱视的比例较逆规散光造成重度弱视高,逆规散光性儿童弱视患者(62.7%)治疗的总有效率比顺规散光性(35.4%)高,组间比较差异有统计学意义(P〈0.05)。结论视知觉学习治疗逆规散光性儿童弱视患者总有效率高于顺规散光性儿童弱视患者。 相似文献
979.
目的:比较特异性抗原致敏的树突状细胞(DC)诱导的杀伤细胞(CIK)和细胞毒性T淋巴细胞(CTL)对B16黑色素瘤的抑瘤作用。方法:采用特异性肿瘤抗原致敏的DC与CIK和CTL细胞共同培养,分析其免疫表型,流式细胞检测癌细胞增殖周期中G0/G1期、S期、G2/M期细胞比率和细胞凋亡指数(AI)、细胞增殖指数(PI)的变化;并用MTT法检测其对肿瘤细胞的抑瘤作用。结果:DC-CIK及DC-CTL均可以影响肿瘤细胞的细胞周期,并具有诱导细胞凋亡的作用,但DC-CIK与DC-CTL之间无显著性差异;DC-CTL细胞组抑瘤作用较DC-CIK明显升高。结论:特异性抗原致敏的DC-CIK与DC-CTL细胞对B16黑色素瘤均有抑瘤作用,但DC-CTL更高效而特异。 相似文献
980.
淋巴细胞活性染色质诱导系统性红斑狼疮样小鼠模型 总被引:1,自引:0,他引:1
目的建立活性染色质诱导系统性红斑狼疮(SLE)样小鼠模型。方法从ConA活化的BALB/c小鼠脾淋巴细胞中提取活性染色质,分别于d 0、d 14、d 21和d 28以染色质100μg在BALB/c小鼠尾根部及背部皮内注射免疫4次,诱导SLE样小鼠模型。目测半定量尿蛋白试纸法检测动物的尿蛋白变化,HE染色法检查动物的肾脏、脾脏病理改变,计算动物的胸腺和脾脏指数,MTT法检测ConA和LPS诱导的T、B淋巴细胞增殖反应,全自动生化分析仪检测血清中Crea和BUN水平,ELISA法检测小鼠血清中ANA、抗dsDNA、IgG1、IgG2a、IL-10、IFN-γ水平,流式细胞术检测脾脏T、B淋巴细胞亚群变化。结果诱导模型小鼠尿蛋白水平升高,出现肾小球肾炎、脾脏增生等病理改变;脾脏指数明显升高,LPS诱导的B淋巴细胞增殖反应增强;血清Crea、BUN、ANA、抗dsDNA、IgG1、IgG2a、IL-10和IFN-γ水平明显升高;脾脏CD19+、CD19+CD21+、CD19+CD23+、CD19+IgD+B淋巴细胞亚群百分比明显升高,CD4+CD25+T淋巴细胞百分比明显下降。结论 ConA活化淋巴细胞的染色质免疫同系BALB/c小鼠成功诱导了SLE样小鼠模型,其血清学、组织病理学及免疫学方面特征与人类SLE临床特征表现相似。 相似文献