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Desferoxamine preconditioning protects against cerebral ischemia in rats by inducing expressions of hypoxia inducible factor 1α and erythropoietin 被引量:1
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作者 李云霞 丁素菊 +2 位作者 肖林 郭卫 詹青 《Neuroscience Bulletin》 SCIE CAS CSCD 2008年第2期89-95,共7页
Objective To investigate whether desferoxamine (DFO) preconditioning can induce tolerance against cerebral ischemia and its effect on the expression of hypoxia inducible factor 1 α (HIF- 1α) and erythropoietin ... Objective To investigate whether desferoxamine (DFO) preconditioning can induce tolerance against cerebral ischemia and its effect on the expression of hypoxia inducible factor 1 α (HIF- 1α) and erythropoietin (EPO) in vivo and in vitro. Methods Rat model of cerebral ischemia was established by middle cerebral artery occlusion with or without DFO administration. Infarct size was examined by TTC staining, and the neurological severity score was evaluated according to published method. Cortical neurons were cultured under ischemia stress which was mimicked by oxygen-glucose deprivation (OGD), and the neuron damage was assessed by MTT assay. Immunofluorescent staining was employed to detect the expressions of HIF-1 and EPO. Results The protective effect induced by DFO (decreasing the infarction volume and ameliorating the neurological function) appeared at 2 d after administration ofDFO (post-DFO), lasted until 7 d and disappeared at 14 d (P 〈 0.05); the most effective action was observed at 3 d post-DFO. DFO induced tolerance of cultured neurons against OGD: neuronal viability was increased 23%, 34%, 40%, 48% and 56% at 8 h, 12 h, 24 h, 36 h, and 48 h, respectively, post-DFO (P 〈 0.05). Immunofluorescent staining found that HIF-1 α and EPO were upregulated in the neurons of rat brain at 3 d and 7 d post-DFO; increase of HIF-1 α and EPO appeared in cultured cortex neurons at 36 h and 48 h post-DFO. Conclusion DFO induced tolerance against focal cerebral ischemia in rats, and exerted protective effect on OGD cultured cortical neurons. DFO significant induced the expression of HIF- 1 α and EPO both in vivo and in vitro. DFO preconditioning can protect against cerebral ischemia, which may be associated with the synthesis of HIF- 1 α and EPO. 展开更多
关键词 desferoxamine ischemia preconditioning hypoxia inducible factor 1 α erythropoietin
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基于CEEMDAN-QPSO-BLS模型的径流预测研究 被引量:2
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作者 刘扬 赵丽 《中国农村水利水电》 北大核心 2024年第1期101-108,共8页
准确的径流预测是水资源优化配置和高效利用的前提,是制定防洪减灾决策的基础,然而受到人类活动、环境、气候等因素的影响,径流序列呈现出非线性、非稳态、多尺度变化的特点,这为径流的精准预测增加了难度。为提高径流预测的精准度和可... 准确的径流预测是水资源优化配置和高效利用的前提,是制定防洪减灾决策的基础,然而受到人类活动、环境、气候等因素的影响,径流序列呈现出非线性、非稳态、多尺度变化的特点,这为径流的精准预测增加了难度。为提高径流预测的精准度和可信度,结合自适应噪声完备集合经验模态分解(Complete Ensemble Empirical Mode Decomposition with Adaptive Noise,CEEMDAN)方法,量子粒子群优化算法(Quantum Particle Swarm Optimization,QPSO)、宽度学习系统(Broad Learning System,BLS)模型,提出了一种基于CEEMDAN-QPSO-BLS组合式的径流预测模型。该组合模型首先使用CEEMDAN方法对原始径流信号进行分解,得到若干相对平稳的本征模态分量。其次利用QPSO算法对BLS模型的特征层节点组数、增强层节点组数和组内节点数进行寻优,得到最优的宽度学习网络拓扑结构,进而使用最优的QPSOBLS对多个稳态分量进行预测,并对预测分量进行重构,从而获得更高的预测精度。以黄河流域小浪底水库的日径流值为实验数据,将EMD-QPSO-BLS、QPSO-BLS作为CEEMDAN-QPSO-BLS的对比模型,并采用纳什效率系数(NSE)、均方根误差(RMSE)、平均绝对误差(MAE)和平均绝对百分比误差(MAPE)作为模型预测可信度和精准度的评价指标。实验表明,在预见期4天内,与QPSO-BLS、EMD-QPSO-BLS模型相比,CEEMDAN-QPSO-BLS的预测精准度分别提高了79.87%、19.80%,可信度分别提高了131.2%、10.98%,径流预测精度的提高,可为防洪抗旱保护人民生命财产和可持续发展提供决策支持。 展开更多
关键词 径流预测 宽度学习 量子粒子群 CEEMDAN EMD
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C57BL/6小鼠微小三毛滴虫的观察与种系发育分析
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作者 温福利 《福建畜牧兽医》 2024年第4期10-12,18,共4页
为鉴定从某外单位引进的C57BL/6小鼠粪样检测中发现的虫体种类,本试验对虫体进行形态学观察,并进行种系发育分析。取C57BL/6小鼠粪样涂片和瑞士染色后进行显微镜观察,提取粪样总DNA,根据三毛滴虫的16S rRNA进行PCR扩增后测序,运用MEGA1... 为鉴定从某外单位引进的C57BL/6小鼠粪样检测中发现的虫体种类,本试验对虫体进行形态学观察,并进行种系发育分析。取C57BL/6小鼠粪样涂片和瑞士染色后进行显微镜观察,提取粪样总DNA,根据三毛滴虫的16S rRNA进行PCR扩增后测序,运用MEGA11进行种系发育分析。显微镜观察发现,虫体符合微小三毛滴虫的形态学特征,测序发现微小三毛滴虫的基因序列与鼠三毛滴虫高度同源。 展开更多
关键词 C57bl/6小鼠 微小三毛滴虫 16S rRNA 种系发育分析
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Expression of hypoxia inducible factor-1 alpha and ischemic erythropoietin tolerance in the brain of cerebral ischemic tolerance model rats 被引量:2
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作者 Renliang Zhao Ruijian Dong Zhongling Sun 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第3期209-212,共4页
BACKGROUND: Hypoxia inducible factor-1 alpha (HIF-1 (x) and erythropoietin(EPO), possessing neuroprotective effect in the cerebral ischemia, might play an important role in the formation of cerebral ischemic tol... BACKGROUND: Hypoxia inducible factor-1 alpha (HIF-1 (x) and erythropoietin(EPO), possessing neuroprotective effect in the cerebral ischemia, might play an important role in the formation of cerebral ischemic tolerance (IT). OBJECTIVE:To observe the neuroprotective effect of cerebral ischemic preconditioning(IPC) of rats, and the expression and mechanism of HIF-1α and target gene erythropoietin in the brain tissue following the formation of cerebral IT. DESIGN : A randomized and controlled observation SETTING: Department of Neurology, the Affiliated Hospital of Medical College, Qingdao University MATERIALS: Totally 84 enrolled adult healthy male Wistar rats of clean grade, weighing 250 to 300 g, were provided by the Animal Experimental Department, Tongji Medical College of Huazhong University of Science and Technology. Ready-to-use SABC reagent kit and rabbit anti-rat HIF-1α monoclonal antibody were purchased from Boshide Bioengineering Co.Ltd (Wuhan); Rabbit anti-rat EPO monoclonal antibody was purchased from Santa Cruz Company (USA). METHODS: This experiment was carried out in the Department of Anatomy, Medical College, Qingdao University during March 2005 to March 2006. ① The 84 rats were divided into 3 groups by a lot: IPC group (n=40), sham-operation group (n=40) and control group (n=4). In the IPC group, middle cerebral artery was occluded for 2 hours respectively on the 1^st, 3^rd, 7^th, 14^th and 21^st days of the reperfusion following 10-minute preischemia was made using a modified middle cerebral artery second suture method from Zea-Longa. The rats were sacrificed 22 hours after reperfusion in the end of middle cerebral artery occlusion (MCAO). That was to say, after 10-minute preischemia, suture was exited to the extemal carotid artery and embedded subcutaneously. Middle cerebral artery was occluded again to form the second reperfusion at the set time point after reperfusion. Twenty-two hours later, rats were sacrificed; In the sham-operation group,the preischemia was substituted by sham-operation(only common carotid artery and crotch were exposed, and MCAO by suture was omitted), and the other procedures were the same as those in the IPC group. In the control group, rats were given sham-operation twice at an interval of one day, and they were sacrificed 24 hours after the second sham-operation. ② Brain tissue was taken from the rats in each group. Cerebral infarction area of each layer was measured with TTC staining, and total cerebral infarction volume (The total cerebral infarction area of each layerxinterspace ) was calculated. After brain tissue was stained by haematoxylin-esoin (HE), the form of nerve cells was observed under an optical microscope, and the expressions of HIF-1α(and EPO protein in the brain tissue were detected with immunohistochemical method. MAIN OUTCOME MEASURES: ①Cerebral infarction volume;②form of nerve cell; ③ the expression of HIF-1α and EPO protein in the brain tissue. RESULTS:Totally 84 rats were enrolled in the experiment. The dead rats were randomly supplied during the experiment, and finally 84 rats entered the stage of result analysis. ① Detection of cerebral infarction volume of rats in each group: Cerebral infarction volume in the IPC group was significantly smaller than that in the sham-operation group on the 1^st, 3^rd and 7^th days after reperfusion respectively [(161.2±6.9) mm^3 vs (219.9±11.2) mm^3, (134.9±9.0) mm^3 vs (218.6±13.0) mm^3, (142.9±13.7) mm^3 vs (221.3±14.2) mm^3, t=-8.924, 10.587,7.947, P〈 0.01]. ② Observation of nerve cell form of brain tissue: HE staining showed that the ischemic degree, range and cerebral edema degree of IPC group were significantly milder than those of sham-operation group. ③ The expressions of HIF-1α and EPO protein in cerebral cortex and hippocampus : The expression of HIF-1αof IPC group was significantly higher than that of sham-operation group on the 1^st, 3^rd and 7^th days after reperfusion respectively (125.93±3.79 vs 117.65±5.60, 140.63±4.64 vs 119.33±4.26, 131.15±2.74 vs 107.60±3.89, t=2.449, 6.763,9.899,P 〈 0.05-0.01). The expression of EPO of IPC group was significantly higher than that of sham-operation group on the 3^rd and 7^th days after perfusion respectively (141.68±3.29 vs 126.33±4.51, 138.88±2.59 vs 125.58±6.18,t=5.499,3.970, P〈 0.05). CONCLUSION : ①IPC can protect the never cells in rat brain and the best time to onset of cerebral IT induced by IPC is 1 to 7 days after reperfusion. ② Neuroprotective effect of cerebral IT might be related to the expression of HIF-1α and its target gene EPO. 展开更多
关键词 Expression of hypoxia inducible factor-1 alpha and ischemic erythropoietin tolerance in the brain of cerebral ischemic tolerance model rats EPO IPC HIF
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Correlation of hypoxia-inducible factor-1 alpha and erythropoietin protein and mRNA to cerebral ischemic tolerance in a focal ischemia/reperfusion model using the twice suture method
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作者 Renliang Zhao Yongjun Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第11期846-852,共7页
BACKGROUND: Numerous studies have shown that transient ischemic preconditioning induces cerebral ischemic tolerance. However, the underlying mechanisms of endogenous protection following ischemic preconditioning rema... BACKGROUND: Numerous studies have shown that transient ischemic preconditioning induces cerebral ischemic tolerance. However, the underlying mechanisms of endogenous protection following ischemic preconditioning remain unclear. OBJECTIVE: To dynamically measure erythropoietin and hypoxia-inducible factor-1α (HIF-1α) mRNA and protein expression at various times following preconditioning, and to investigate effects of erythropoietin and HIF-1α on cerebral ischemic tolerance in a model of focal ischemia/reperfusion established using the twice suture method. DESIGN, TIME AND SETTING: The randomized, controlled study was performed at the Institute of Anatomy, Medical College, Qingdao University, China from March 2006 to March 2007. MATERIALS: Rabbit anti-rat HIF-1α monoclonal antibody and biotinylated goat anti-rabbit IgG (Boster, China), rabbit anti-rat erythropoietin monoclonal antibody (Santa Cruz Biotechnology, USA), and one-step RT-PCR kit (Qiagen, Germany) were used in this study. METHODS: A total of 99 healthy, male, Wistar rats were randomly assigned to three groups: sham surgery (n = 9), non-ischemic preconditioning (n = 45), and ischemic preconditioning (n = 45). In the ischemic preconditioning group, rat models of pre-ischemia-reperfusion-ischemia-reperfusion were established by occluding the left middle cerebral artery using the twice suture method. In the non-ischemic preconditioning group, pre-ischemia was replaced by sham surgery. Subsequently, the ischemic preconditioning and non-ischemic preconditioning groups were equally divided into five subgroups according to time of first reperfusion, including 1-, 3-, 7-, 14-, and 21-day subgroups. The sham surgery group received the sham surgery twice. MAIN OUTCOME MEASURES: HIF-la and erythropoietin protein expression was measured in the cerebral cortex, corpus striatum, and hippocampus of the ischemic hemisphere. HIF-1α and erythropoietin mRNA expression were determined in the frontal and parietal cortex of the ischemic hemisphere. RESULTS: (1) Intergroup comparison: compared with the non-ischemic preconditioning group, HIF-1α protein expression significantly increased in the rat cerebral cortex, corpus striatum, and hippocampus in the ischemic hemisphere at 1,3, and 7 days following reperfusion in the ischemic preconditioning group (P 〈 0.05 or P 〈 0.01). Erythropoietin protein expression significantly increased in the cerebral cortex, corpus striatum, and hippocampus, as well as HIF-1α and erythropoietin mRNA expression in the frontal and parietal cortex in the ischemic hemisphere, at 3 and 7 days following reperfusion in the ischemic preconditioning group (P 〈 0.05). (2) Temporal expression: HIF-1α protein expression in the rat cerebral cortex, corpus striatum, and hippocampus, as well as HIF-la mRNA expression in the frontal and parietal cortex, in the ischemic hemisphere increased at 3 days, and gradually decreased from 7 days following reperfusion in the ischemic preconditioning group. Temporal erythropoietin protein and mRNA expression was consistent with HIF-1α protein expression. (3) Correlation: erythropoietin mRNA expression positively correlated with HIF-1α mRNA expression (r= 0.737, P 〈 0.01). CONCLUSION: Ischemic preconditioning induced cerebral ischemic tolerance. Pre-ischemiainduced increase in endogenous HIF-1αexpression, as well as its target gene erythropoietin, participated in the formation of cerebral ischemic tolerance. 展开更多
关键词 ischemic tolerance ischemic preconditioning cerebral ischemia RAT hypoxia-inducible factor-1α erythropoietin
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Constitutively Active Soluble Form of Erythropoietin Receptor Suppresses Growth and Angiogenesis of Xenografts of Transfected Cancer Cell Lines
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作者 Yoshiko Yasuda Yasuhiro Maeda +9 位作者 Satoshi Hara Motoyoshi Tanaka Eiji Koike Yoh Watanabe Seiji Masuda Harufumi Yamasaki Katsumi Okumoto Hiroyoshi Konishi Yoshitaka Horiuchi Hiroshi Hoshiai 《Journal of Cancer Therapy》 2011年第1期40-53,共14页
We examined the effect of blocking the erythropoietin (Epo) signaling using an anti-Epo antibody, soluble form of Epo receptor (sEpoR) capable of binding to Epo or EpoR antagonist, and proved to be effective against x... We examined the effect of blocking the erythropoietin (Epo) signaling using an anti-Epo antibody, soluble form of Epo receptor (sEpoR) capable of binding to Epo or EpoR antagonist, and proved to be effective against xenografts of female reproductive organ malignancies and of cancer cell lines in nude mice. We transfected seven cancer cell lines of various origins to express constitutively active sEpoR, and examined their tumorigenesis in nude mice. Suppression of the tumor growth, decrease in viable and proliferating cells and reduction of vascular density were seen individually in all xenografts of transfected cell lines compared with the controls. Quantitative RT-PCR analyses showed that expression levels of Epo, EpoR, ?1A-adrenaline receptor (?1A-ADR) and muscalinic acetylcholine receptor subunit 3 mRNAs (m3-AchR) were higher in the majority of the wild-type xenografts than in the corresponding cell lines except for A549. In some of the transfected xenografts, EpoR, ?1A-ADR and m3-AchR mRNAs were down-regulated. Western blot analyses revealed that the constitutively activated ERK1/2MAPK was discernible in the majority of non-transfected cell lines and was reduced in the transfected cell lines. However, it was regained after exposure to acetylcholine and/or noradrenaline. These findings suggest that constitutively active sEpoR can effectively destroy the xenografts but signals from the autonomic neurotransmitters of the host produced under stress may interfere with this antitumor activity. 展开更多
关键词 erythropoietin erythropoietin RECEPTOR Soluble Form of erythropoietin RECEPTOR ERK1/2/MAPK Adrenoreceptor ACETYLCHOLINE RECEPTOR Immunohistochemistry Western blOT Real-Time RT-PCR NUDE Mice
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Cell-Based Biological Markers for Blood-Enriching Chinese Herbs: Erythropoietin Production in HepG2 Cells and Nitric Oxide Release in Human Umbilical Vein Endothelial Cells (HUVECs)
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作者 Hoi Yan Leung Kam Ming Ko 《Chinese Medicine》 2023年第2期57-67,共11页
Chinese tonifying herbs, which are classified into four functional categories (namely, Yang, Qi, Yin, Blood) are commonly used for restoring normal body function and the prevention of diseases. To explore cell-based b... Chinese tonifying herbs, which are classified into four functional categories (namely, Yang, Qi, Yin, Blood) are commonly used for restoring normal body function and the prevention of diseases. To explore cell-based biological markers for Blood-enriching Chinese herbs, we investigate the effect of 11 commonly used Blood-enriching herbs on erythropoietin (EPO) production in HepG2 cells. Herbs for nourishing Yin were tested for determining the specificity of Blood-enriching herbs in inducing EPO production. In addition, the effects of Blood-enriching herbs on nitric oxide (NO) production in both HepG2 cells and human umbilical vein endothelial cells (HUVECs) were also investigated. The results indicated that methanolic extracts of Blood-enriching herbs (but not Yin-nourishing herbs) showed characteristic pharmacological activity in inducing EPO production in HepG2 cells and NO release in HUVECs. The experimental findings, therefore, support the use of cell-based EPO production and NO release as biological markers for Blood-enriching Chinese tonifying herbs. 展开更多
关键词 blood-Enriching Chinese Herbs erythropoietin Nitric Oxide
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枸杞多糖对C57BL/6J骨质疏松症小鼠的早期防治
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作者 刘艺洁 赵薇 +9 位作者 李林隆 李海林 姚建花 李智东 刘飞 丁玉梅 孟海伟 于洋 王银 苗珍花 《宁夏医科大学学报》 2024年第6期586-591,共6页
目的探讨枸杞多糖(LBP)对C57BL/6J骨质疏松症小鼠的早期防治作用。方法选用12周C57BL/6J雌鼠,采用双侧卵巢完全切除术制备骨质疏松症模型,假手术组切除卵巢周围脂肪组织,术后1周,选取手术成功的小鼠分为假手术组、模型组和LBP组。LBP组... 目的探讨枸杞多糖(LBP)对C57BL/6J骨质疏松症小鼠的早期防治作用。方法选用12周C57BL/6J雌鼠,采用双侧卵巢完全切除术制备骨质疏松症模型,假手术组切除卵巢周围脂肪组织,术后1周,选取手术成功的小鼠分为假手术组、模型组和LBP组。LBP组给予灌胃LBP 0.1 g·kg^(-1),1次/d,连续12周,假手术组和模型组灌胃等量蒸馏水。酶联免疫吸附(ELISA)法检测小鼠血清中雌二醇(E_(2))含量;生物化学方法检测血清氧化应激指标丙二醛(MDA)、超氧化物歧化酶(SOD)含量;Micro CT扫描胫骨微观结构,观察骨小梁厚度(Tb·Th)、骨表面积和骨体积之比(BS/BV)、骨小梁分离度(Tb·Sp)、骨密度(BMD)、骨体积分数(BV/TV)、骨体积(BV)的变化。结果与假手术组小鼠比较,模型组小鼠的体质量增长率升高、子宫脏器系数明显减小、血清E_(2)含量下降、血清氧化应激指标MDA含量增高、SOD活力降低(P均<0.01);与模型组小鼠比较,LBP组小鼠子宫脏器系数、血清E_(2)含量差异均无统计学意义(P均>0.05),但体质量增长率下降、血清MDA含量降低、SOD活力增加(P均<0.01),骨组织BMD、BV升高(P均<0.05),Tb·Th及BV/TV均显著升高(P均<0.01)。胫骨三维重建图显示,模型组骨皮质变薄,呈现骨质疏松改变,骨小梁数量减少,排列紊乱,髓腔明显扩大;LBP组较模型组骨小梁数量增加。结论LBP可能通过调控早期骨质疏松症小鼠的氧化应激反应,发挥改善骨质疏松的作用。 展开更多
关键词 枸杞多糖 C57bl/6J小鼠 骨质疏松症 氧化应激 骨密度
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C57BL/6N小鼠早期视网膜变性及小胶质细胞活化状态研究
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作者 孟欢 邓婷婷 +4 位作者 刘自强 侯小玉 马传政 苑维 金明 《国际眼科杂志》 CAS 2024年第10期1536-1541,共6页
目的:观察C57BL/6N(Crb1 rd8/rd8)小鼠早期视网膜变性以及小胶质细胞的活化情况。方法:取雄性SPF级C57BL/6N小鼠15只、C57BL/6J小鼠15只,正常饲养。分别在入组时,入组4、8、12 wk,使用Micron-Ⅲ小动物视网膜影像系统进行双眼彩色眼底照... 目的:观察C57BL/6N(Crb1 rd8/rd8)小鼠早期视网膜变性以及小胶质细胞的活化情况。方法:取雄性SPF级C57BL/6N小鼠15只、C57BL/6J小鼠15只,正常饲养。分别在入组时,入组4、8、12 wk,使用Micron-Ⅲ小动物视网膜影像系统进行双眼彩色眼底照相检查计算病变数量、病变面积。观察结束后处死小鼠,摘取右侧眼球制备视网膜组织切片,进行HE染色后光镜下观察视网膜组织形态;采用免疫组织化学染色分析两组小鼠视网膜CX3CR1的表达水平及位置。摘取左侧眼球分离视网膜,使用Western-Blot检测CD86、CD206的表达情况,使用电化学发光法测定视网膜中IL-1β、IL-6、TNF-α、IL-4、IL-10炎性因子含量水平。结果:眼底彩照结果显示在入组4、8、12 wk,C57BL/6N组眼底病变数量均较入组时显著增加,与C57BL/6J组同时间点变化量比较均有差异(均P<0.05);眼底病变面积变化量两组间入组12 wk有差异(P<0.05),各组内变化量比较均无差异(均P>0.05);视网膜组织HE染色示:C57BL/6N组视网膜结构异常,细胞排列疏松、紊乱,光感受器层向视网膜内侧明显的玻璃膜疣样凸起,C57BL/6J组视网膜结构清晰,细胞排列有序,无明显异常;免疫组化结果示:C57BL/6N组视网膜中CX3CR1高表达于神经节细胞层、内外丛状层、感光细胞层及病灶处位置,平均光密度为0.285±0.056,C57BL/6J组为0.189±0.084(P<0.05);Western-Blot结果显示:与C57BL/6J组相比,C57BL/6N组视网膜CD86、CD206蛋白有不同程度升高,两组CD86蛋白表达有差异(P<0.05);细胞因子检测结果显示:C57BL/6N组IL-1β、TNF-α水平显著高于C57BL/6J组,而IL-10含量则明显较低(均P<0.05)。结论:C57BL/6N(Crb1 rd8/rd8)小鼠视网膜变性进展缓慢,随年龄呈进行性加重,病灶部位视网膜结构紊乱,伴有以M1型极化为主的小胶质细胞浸润。 展开更多
关键词 C57bl/6N 视网膜变性 年龄相关性黄斑变性 小胶质细胞 极化
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U2BL调控拟南芥下胚轴伸长的机制研究
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作者 张婉露 丁勇 《植物科学学报》 CAS CSCD 北大核心 2024年第1期66-74,共9页
下胚轴的伸长在植物早期存活和后期生长发育过程中均具有重要作用。本研究对拟南芥(Arabidopsis thaliana(L.)Heynh.)突变体进行了筛选,得到了具有短下胚轴表型的突变体u2bl,并对其下胚轴变短机制进行了初步研究。结果显示,突变体u2bl... 下胚轴的伸长在植物早期存活和后期生长发育过程中均具有重要作用。本研究对拟南芥(Arabidopsis thaliana(L.)Heynh.)突变体进行了筛选,得到了具有短下胚轴表型的突变体u2bl,并对其下胚轴变短机制进行了初步研究。结果显示,突变体u2bl在不同光照条件下均表现出下胚轴较短的表型。细胞学实验表明,突变体u2bl下胚轴细胞长度的降低是其下胚轴较短的原因。赤霉素(GAs)是促进下胚轴伸长的主效应因子。但u2bl突变体对外源GA处理及内源GA合成抑制剂多效唑(PAC)处理均不敏感,表明U2BL基因可能影响GA的信号转导。亚细胞定位结果表明,U2BL在细胞核中富集。荧光定量Q-PCR分析结果显示,在u2bl突变体中,PRE1、SAUR16、YUC2、YUC8和PIF4等基因的表达均有显著下调,U2BL可能通过调控上述基因来间接调控下胚轴的伸长。本研究结果为进一步探讨U2BL在拟南芥生长发育及在其他物种中可能行使的功能提供了参考。 展开更多
关键词 U2bl基因 拟南芥 下胚轴 赤霉素
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Transcriptomic and bioinformatics analysis of the mechanism by which erythropoietin promotes recovery from traumatic brain injury in mice 被引量:1
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作者 Weilin Tan Jun Ma +9 位作者 Jiayuanyuan Fu Biying Wu Ziyu Zhu Xuekang Huang Mengran Du Chenrui Wu Ehab Balawi Qiang Zhou Jie Zhang Zhengbu Liao 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期171-179,共9页
Recent studies have found that erythropoietin promotes the recovery of neurological function after traumatic brain injury.However,the precise mechanism of action remains unclea r.In this study,we induced moderate trau... Recent studies have found that erythropoietin promotes the recovery of neurological function after traumatic brain injury.However,the precise mechanism of action remains unclea r.In this study,we induced moderate traumatic brain injury in mice by intrape ritoneal injection of erythro poietin for 3 consecutive days.RNA sequencing detected a total of 4065 differentially expressed RNAs,including 1059 mRNAs,92 microRNAs,799 long non-coding RNAs,and 2115circular RNAs.Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analyses revealed that the coding and non-coding RNAs that were differentially expressed after traumatic brain injury and treatment with erythropoietin play roles in the axon guidance pathway,Wnt pathway,and MAPK pathway.Constructing competing endogenous RNA networks showed that regulatory relationship between the differentially expressed non-coding RNAs and mRNAs.Because the axon guidance pathway was repeatedly enriched,the expression of Wnt5a and Ephb6,key factors in the axonal guidance pathway,was assessed.Ephb6 expression decreased and Wnt5a expression increased after traumatic brain injury,and these effects were reversed by treatment with erythro poietin.These findings suggest that erythro poietin can promote recove ry of nerve function after traumatic brain injury through the axon guidance pathway. 展开更多
关键词 axon guidance bioinformatics analysis competing endogenous RNA erythropoietin Gene Ontology Kyoto Encyclopedia of Genes and Genomes non-coding RNA RNA sequencing transcriptomics traumatic brain injury
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C57BL/6小鼠炎症性肠病模型的建立与指标评价
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作者 何家宇 杨茗淇 +4 位作者 伍娇 杨宇 姚欢 易金娥 孔丽 《中国畜牧兽医》 CAS CSCD 北大核心 2024年第9期4153-4163,共11页
【目的】通过葡聚糖硫酸钠(dextran sulfate sodium,DSS)或脂多糖(lipopolysaccharide,LPS)刺激构建小鼠炎症性肠病(inflammatory bowel disease,IBD)模型,为IBD研究提供高效经济的模型参考,并为IBD抗炎药物筛选与药效评价提供可靠的方... 【目的】通过葡聚糖硫酸钠(dextran sulfate sodium,DSS)或脂多糖(lipopolysaccharide,LPS)刺激构建小鼠炎症性肠病(inflammatory bowel disease,IBD)模型,为IBD研究提供高效经济的模型参考,并为IBD抗炎药物筛选与药效评价提供可靠的方法支撑。【方法】本试验以C57BL/6雄性小鼠为研究对象,分别暴露于不同浓度的DSS(3%、4%和5%)7 d或LPS(5、10和20 mg/kg)4 h。通过测量小鼠结肠长度,HE染色观察肠道形态结构及实时荧光定量PCR检测肠道炎性因子的mRNA表达等对模型进行评价。【结果】DSS诱导小鼠结肠变短、病理出血、腺体萎缩、结构排列絮乱、炎性细胞浸润以及结肠中炎性因子白细胞介素-1β(interleukin-1β,IL-1β)、IL-6、IL-10和肿瘤坏死因子-α(tumour necrosis factor-α,TNF-α)的mRNA表达显著上升(P<0.05),4%DSS即可高效建立IBD模型。同时,LPS引起小鼠肠系膜出血、肠道肿胀和充血,肠绒毛高度降低,隐窝深度升高,小肠中IL-10和IL-1βmRNA水平升高、IL-6 mRNA水平下降,十二指肠和回肠TNF-αmRNA水平上升,空肠TNF-αmRNA水平降低,且以5 mg/kg LPS综合影响最为显著。【结论】4%DSS和5 mg/kg LPS是C57BL/6小鼠IBD模型建立的最适浓度,肠道病理形态改变、肠道炎性细胞浸润及炎性因子IL-1β、IL-6、IL-10和TNF-α的mRNA表达异常是评价IBD模型的重要指标。 展开更多
关键词 葡聚糖硫酸钠(DSS) 脂多糖(LPS) 炎症性肠病 肠道炎症 C57bl/6小鼠
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BL Lac的光学多普勒因子估算
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作者 黄家伟 潘树蓉 +3 位作者 吴健 叶旭鸿 曹健鸿 樊军辉 《天文学报》 CAS CSCD 北大核心 2024年第5期70-77,共8页
蝎虎天体(BL Lacertae object,BL Lac)是一类特殊的活动星系核,表现出极端的观测特征,如高光度和偏振、快速光变、超光速运动、射电核主导、极高能辐射等,极端观测特性可能都与喷流效应有关,而表征喷流效应的物理量是多普勒因子(Doppler... 蝎虎天体(BL Lacertae object,BL Lac)是一类特殊的活动星系核,表现出极端的观测特征,如高光度和偏振、快速光变、超光速运动、射电核主导、极高能辐射等,极端观测特性可能都与喷流效应有关,而表征喷流效应的物理量是多普勒因子(Doppler factor).多普勒因子有助于了解BL Lac的辐射物理和本征特性.基于BL Lac和Fanaroff-Riley typeⅠ/Fanaroff-Riley typeⅡ(G)的统一模型思路,提出BL Lac的本征视星等与红移(哈勃图)的分布应该与FRⅠ/FRⅡ(G)的观测视星等与红移的分布相似,并提出了估算BL Lac的光学多普勒因子的方法.该方法所估算的多普勒因子与前人的光学多普勒因子比较具有很好的相关性,说明该光学波段估算BL Lac多普勒因子的方法是可靠的. 展开更多
关键词 蝎虎天体:普通 星系:活动 星系:距离和红移 星系:喷流
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Does recombinant human erythropoietin accelerate correction of post-ulcer-bleeding anaemia?A pilot study
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作者 SpirosD.Ladas DimitriosPolymeros +4 位作者 ThomasPagonis KonstantinosTriantafyllou MariaHatziargiriou SotiriosA.Raptis Gregorios Paspatis 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第4期586-589,共4页
AIM:Anaemia caused by acute upper gastrointestinal bleeding is treated with blood transfusion or iron,but patients usually face a two-month recovery period from post- haemorrhage anaemia.This prospective,randomised,op... AIM:Anaemia caused by acute upper gastrointestinal bleeding is treated with blood transfusion or iron,but patients usually face a two-month recovery period from post- haemorrhage anaemia.This prospective,randomised,open, pilot study was designed to investigate whether recombinant human erythropoietin(Epoetin)therapy accelerate haematocrit increase in the post-bleeding recovery period. METHODS:We studied hospitalised patients admitted because of acute ulcer bleeding or haemorrhagic gastritis, who had a haematocrit of 27-33% and did not receive blood transfusions.One day after the endoscopic confirmation of cessation of bleeding,they were randomised either to erythropoietin(20 000 IU Epoetin alfa subcutaneously,on days 0,4 and 6)plus iron(100 mg im,on days 1-6,(G_1)or iron only(G_2).Haematocdt was measured on days 0,6,14, 30,45,and 60,respectively. RESULTS:One patient from G_1 and two from G_2 were lost to follow-up.Therefore,14 and 13 patients from G_1 and G_2 respectively were analysed.Demographic characteristics,serum iron,ferritin,total iron binding capacity,reticulocytes,and haernatoait were not significantly different at entry to the study. Median reticulocyte counts were significantly different between groups on day six(G_1:4.0,3.0-6.4 vs G_2:3.5,2.1-4.4%, P=0.03)and median haematocrit on day fourteen [G_1:35.9, 30.7-41.0 vs G_2:32.5,29.5-37.0%(median,range),P=0.04]. CONCLUSION:Erythropoietin administration significantly accelerates correction of anemia after acute ulcer bleeding. The haematocrit gain is equivalent to one unit of transfused blood two weeks after the bleeding episode. 展开更多
关键词 Acute Disease Adult Aged ANEMIA erythropoietin Recombinant DOSAGE Female Follow-Up Studies Gastrointestinal Hemorrhage Humans Male Middle Aged Peptic Ulcer Pilot Projects Prospective Studies Treatment Outcome
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一种可快速验证的可聚合BLS签名方案
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作者 潘天雨 赵运磊 《密码学报(中英文)》 CSCD 北大核心 2024年第4期799-806,共8页
BLS签名是一种双线性映射友好椭圆曲线上的数字签名方案,它具有签名大小短、在聚合签名场景中验证高效、支持同态性与非交互聚合等优点.但由于需要进行双线性映射操作,单个BLS签名的验证算法相对较慢,这阻碍了其在区块链系统中进一步的... BLS签名是一种双线性映射友好椭圆曲线上的数字签名方案,它具有签名大小短、在聚合签名场景中验证高效、支持同态性与非交互聚合等优点.但由于需要进行双线性映射操作,单个BLS签名的验证算法相对较慢,这阻碍了其在区块链系统中进一步的应用.本文提出了一种BLS签名方案的变体—CPABLS,其主要优点如下:第一,将Chaum-Pedersen离散对数相等性证明纳入签名中,使得签名验证算法不再需要双线性映射操作,从而提升了验证速度;第二,在公钥聚合时只需对各个签名者的公钥简单求和,而无需进行大量的标量乘法操作;第三,相比于群G2,签名验证算法可在群G1中更快地进行哈希到曲线和聚合公钥检验操作.给出了该方案在聚合签名安全模型中的安全证明及原型实现,并进行了性能测试与效率评估. 展开更多
关键词 blS聚合签名 Chaum-Pedersen证明 高效验证
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基于RBF-BLS面向电动汽车低碳安全出行的SOH估计方法
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作者 李春喜 乔涵哲 +3 位作者 姚刚 姜淏予 崔向科 葛泉波 《上海交通大学学报》 EI CAS CSCD 北大核心 2024年第9期1454-1464,共11页
电动汽车充电过程的安全性与动力电池组的健康状态(SOH)紧密相关,因此SOH的高性能实时估计是充电过程中安全检测的重要基础.由于动力电池组的SOH受复杂结构、电芯类型、驾驶习惯、环境温度和充电行为等因素的深度影响,现有基于单个或少... 电动汽车充电过程的安全性与动力电池组的健康状态(SOH)紧密相关,因此SOH的高性能实时估计是充电过程中安全检测的重要基础.由于动力电池组的SOH受复杂结构、电芯类型、驾驶习惯、环境温度和充电行为等因素的深度影响,现有基于单个或少量特定电池电芯实验数据的方法研究在面对整车动力电池组实时SOH估计时遭遇模型复杂、数据缺失、实时性差、精度不足等难题.针对建模困难、实时性和精度不足等问题,应用多方法集成融合思想,在电池经验退化模型上引入径向基函数(RBF)优化的宽度学习(BLS)神经网络,提出一种高性能的动力电池组SOH估计方法.首先,该方法采用经验退化模型和离线历史充电数据得到初步的SOH值;其次,应用RBF神经网络给出一种BLS系统中初始权重矩阵的确定方法,建立经验退化与径向基函数优化的宽度学习神经网络(RBF-BLS);再次,采用RBF-BLS神经网络和实时充电数据训练得到估计误差,并对经验退化模型得到的SOH进行补偿,从而得到更高精度的SOH估计值;最后,采用基于充电运营企业实际充电数据的计算机仿真实例来验证新方法的有效性和优越性. 展开更多
关键词 充电安全 健康状态 经验退化模型 宽度学习
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Evaluation of Hemoglobin and Serum Erythropoietin Levels in Patients with Polycythemia Vera and Secondary Polycythemia
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作者 Alireza Khorshid Daniel González Jianzhi Zhang 《Journal of Biosciences and Medicines》 2024年第8期51-59,共9页
Objective: This study compares hemoglobin and erythropoietin levels in patients with polycythemia vera and secondary polycythemia. Study Design: A retrospective cross-sectional study evaluating the serum erythropoieti... Objective: This study compares hemoglobin and erythropoietin levels in patients with polycythemia vera and secondary polycythemia. Study Design: A retrospective cross-sectional study evaluating the serum erythropoietin and hemoglobin levels in patients with polycythemia vera and secondary polycythemia. This study was performed simultaneously in Texas state of the U.S. and Fars Province in Iran. Methods: Hemoglobin, hematocrit and erythropoietin test results were collected from patients aged 19 to 75 years who were diagnosed with polycythemia vera and secondary polycythemia. Patients records with history of thrombocythemia, congestive heart failure, dyspnea, anemia and pregnant woman were excluded from study. Patients in each decade of life were examined in separate groups, so that changes in hemoglobin related to aging did not affect the research results. Results: 75% of the patients were men, and 25% were women. A total of 1580 patients were analyzed in this study. 57.3% of patients in UTMB and 38.8 patients in Iran have hemoglobin level above 17 mg/dl. 74% of patients in UTMB and 88% of patients in Iran have erythropoietin below 10 IU/mL. Polycythemia in UTMB was more common in people over 50 and in Iran in patients under 50 years old. The serum hemoglobin and erythropoietin levels in patients with polycythemia vera were not significantly different in compare to secondary polycythemia patients. Data showed that there were 84 polycythemia patients per 100,000 people. The results of this study in UTMB and Iran showed that 4.5% and 7%, respectively, of patients with polycythemia had a positive JAK2 test. Conclusion: Low erythropoietin levels may not be helpful in differentiating polycythemia vera from secondary polycythemia. . 展开更多
关键词 Polycythemia Vera erythropoietin JAK2 Secondary Polycythemia
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Umbilical Cord Blood CD33 and Erythropoietin Levels of Pregnants with Abnormal Doppler Waveforms and to Compare with Normal Pregnancies
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作者 Nilay Karaca Gokhan Bolluk +2 位作者 Yasam Kemal Akpak Aslihan Erken Serkan Oral 《Open Journal of Obstetrics and Gynecology》 2015年第4期234-238,共5页
Objective: In this study, we aimed to investigate umbilical cord blood CD33 and erythropoietin (EPO) levels of pregnants with abnormal umbilical and uterine artery doppler waveforms and to compare with normal pregnanc... Objective: In this study, we aimed to investigate umbilical cord blood CD33 and erythropoietin (EPO) levels of pregnants with abnormal umbilical and uterine artery doppler waveforms and to compare with normal pregnancies. Materials and Methods: Total 40 pregnant women were included in this study. Of these 40 women, while 20 patients had abnormal umbilical and uterine artery doppler waveforms, the other 20 patients had normal umbilical and uterine artery doppler waveforms. After the delivery, blood samples were taken from umbilical artery of double clemped umbilical cord for blood gas parameters, EPO and CD33 levels. Sociodemographic findings, antepartum, intrapartum test results, labor and delivery characteristics and newborn examination results were recorded. Blood gas parameters, EPO and CD33 levels between groups were analyzed. Mann-Whitney U test and t-test were used as statistical methods. Results: There were no differences between parity, gestational ages and newborn weights of the groups. Cord blood CD33 and EPO levels of group with abnormal umbilical and uterine artery doppler waveforms were significantly higher than group with normal umbilical and uterine artery doppler waveforms (p < 0.01). Conclusion: Pathology on doppler screen shows to us a connection between chronic hypoxemia and abnormal on doppler screen. Preference of high blood CD33 levels for cord blood transplantation especially during last years can also be used with preference of cord blood with abnormal doppler findings. 展开更多
关键词 Antenatal Care CD33 Doppler Ultrasonography erythropoietin PERINATOLOGY Umbilical Cord blood
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孕期低剂量镉暴露对C57BL/6母鼠肾脏组织的毒性损伤作用
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作者 刘建军 许鹏 《农业技术与装备》 2024年第7期109-111,114,共4页
为研究孕期低剂量镉暴露对母鼠肾脏的毒性效应,基于前期构建的孕期低剂量镉暴露小鼠模型,通过组织显微切片技术对镉暴露母鼠的肾脏组织结构进行观察,并通过实时定量PCR法和蛋白质免疫印迹法对肾脏中炎症相关基因和凋亡调控基因的mRNA和... 为研究孕期低剂量镉暴露对母鼠肾脏的毒性效应,基于前期构建的孕期低剂量镉暴露小鼠模型,通过组织显微切片技术对镉暴露母鼠的肾脏组织结构进行观察,并通过实时定量PCR法和蛋白质免疫印迹法对肾脏中炎症相关基因和凋亡调控基因的mRNA和蛋白质表达水平进行检测。实验结果显示:孕期低剂量镉暴露可导致肾脏结构出现一定程度的病变,如肾小球内细胞数目增多,肾小囊变窄,肾小球略微肿胀等;与对照组相比,镉暴露母鼠肾脏中凋亡功能调控基因Bax的mRNA和蛋白质表达水平显著升高。综上所述,孕期低剂量镉暴露可导致母体肾脏结构发生损伤,该毒性作用可能与凋亡调控基因Bax的表达水平升高相关。研究结果旨在阐明孕期低剂量镉暴露对母体器官的毒性效应机制,为镉暴露下家畜的母胎健康风险评估和环境管理提供基础数据支持。 展开更多
关键词 孕期暴露 肾脏 C57bl/6小鼠
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C57BL/6J小鼠与昆明小鼠NIAAA法酒精性肝病造模效果的比较
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作者 吕皓 林川 +3 位作者 陈红 杨晨晨 向欣 韩春梅 《塔里木大学学报》 2024年第3期43-48,共6页
为了对比C57BL/6J小鼠和昆明小鼠酒精性肝病模型建造效果及建模完成后续肝脏生化指标变化情况,为酒精性肝病的治疗研究提供基础依据,试验选择雌性C57BL/6J小鼠和昆明小鼠各36只,随机分为对照组(液体饲料+麦芽糊精)、建模16 d组与建模19 ... 为了对比C57BL/6J小鼠和昆明小鼠酒精性肝病模型建造效果及建模完成后续肝脏生化指标变化情况,为酒精性肝病的治疗研究提供基础依据,试验选择雌性C57BL/6J小鼠和昆明小鼠各36只,随机分为对照组(液体饲料+麦芽糊精)、建模16 d组与建模19 d组(液体饲料+酒精,n=12)。利用NIAAA法建造酒精性肝病小鼠模型,并分别于建模第16 d、建模第19 d取其血清及肝组织进行生化指标检测及病理切片观察。结果显示,C57BL/6J小鼠建模16 d组和建模19 d组与昆明小鼠建模16 d组的小鼠血清ALT、AST含量,肝脏MDA、TG含量均分别显著高于其对照组小鼠(P<0.05);而血清ALB含量、肝脏SOD活力显著低于其对照组小鼠(P<0.05)。C57BL/6J建模16 d组和建模19 d组小鼠的肝脏GSH含量和肝脏系数显著高于其对照组小鼠(P<0.05),但昆明小鼠建模19 d组除了肝脏SOD活力显著低于其对照组小鼠(P<0.05),其他指标均与其对照组小鼠无显著差异。病理切片结果表明,与对照组相比,建模16 d组2种小鼠肝细胞排列紊乱,肝细胞索断裂,肝细胞出现炎性浸润和脂肪液滴。C57BL/6J小鼠建模19 d组肝组织仍呈现病变,而昆明小鼠建模19 d组肝细胞已逐渐恢复正常排列。与昆明小鼠相比,C57BL/6J小鼠对于酒精的肝脏氧化应激损伤更严重,酒精性肝病模型更稳定。 展开更多
关键词 C57bl/6J小鼠 昆明小鼠 NIAAA法 酒精性肝病 生化指标 病理变化
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