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排序方式: 共有1297条查询结果,搜索用时 0 毫秒
961.
Zhang X  Xiao Z  Liu X  Du L  Wang L  Wang S  Zheng N  Zheng G  Li W  Zhang X  Dong Z  Zhuang X  Wang C 《PloS one》2012,7(2):e31868
Colorectal cancer (CRC) is the third most common malignancy in the world. The risk of death is closely correlated to the stage of CRC at the time of primary diagnosis. Therefore, there is a compelling need for the identification of blood biomarkers that can enable early detection of CRC. We used a quantitative proteomic approach with isobaric labeling (iTRAQ) to examine changes in the plasma proteome of 10 patients with CRC compared to healthy volunteers. Enzyme-Linked Immunosorbnent Assay (ELISA) and Western blot were used for further validation. In our quantitative proteomics analysis, we detected 75 human plasma proteins with more than 95% confidence using iTRAQ labeling in conjunction with microQ-TOF MS. 9 up-regulated and 4 down-regulated proteins were observed in the CRC group. The ORM2 level in plasma was confirmed to be significantly elevated in patients suffering from CRC compared with the controls. ORM2 expression in CRC tissues was significantly increased compared with that in corresponding adjacent normal mucous tissues (P<0.001). ITRAQ together with Q-TOF/MS is a sensitive and reproducible technique of quantitative proteomics. Alteration in expression of ORM2 suggests that ORM2 could be used as a potential biomarker in the diagnosis of CRC.  相似文献   
962.
Nakata H  Nakamura S 《FEBS letters》2007,581(10):2047-2054
The change in the number of post-synaptic alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA)-type glutamatergic receptors (AMPARs) by neuronal activity is recognized as a molecular basis of synaptic plasticity. Here, we show that Ca(2+) transients evoked by brain-derived neurotrophic factor (BDNF) induce translocation of a subunit of AMPAR, GluR1, but not NMDAR, to the post-synaptic membrane in cultured cortical pyramidal neurons. Among BDNF-induced Ca(2+) transients, that dependent on IP3R was fully required, while store-operated calcium influx through the non-selective cation channel TRPC (transient receptor potential canonical) was partially required for the GluR1 up-regulation, suggesting that spatial and temporal calcium signaling regulate translocation of GluR1 to the polarized membrane domain.  相似文献   
963.
Hypera postica is a univoltine invasive pest of alfalfa, Medicago sativa, in North America. In Japan, H. postica was first found in 1982 from Fukuoka and Okinawa Prefectures and became a serious pest of Chinese milk vetch, Astragalus sinicus, cultivated as a honey source for humans and green manure for rice. In North America, three strains, Western, Eastern and Egyptian, have been identified and the Western strain is infected with Wolbachia, which causes complete inter‐strain reproductive incompatibility. In contrast, only Western and Egyptian strains had been reported throughout Japan and none of the Western strain examined for the Fukuoka populations in northern Kyushu was infected with Wolbachia. First, we screened populations from northern Kyushu collected since 1982 for geographical and chronological distribution of the Eastern strain. The Eastern strain has been found at low frequencies since 1985 and is still present in 2014. Second, we experimentally tested our hypothesis that inter‐strain crosses between uninfected Western‐strain males and Egyptian‐strain females should produce viable offspring. We crossbred virgin adults reared individually from field‐collected larvae and confirmed that the F1 eggs of crosses between the Western‐strain males and the Egyptian‐strain females develop successfully into larvae.  相似文献   
964.
Higher plasma urate level is reported to be associated with a reduced risk and slower progression of Parkinson's disease (PD). In this study, we explored the effects of urate on dopaminergic neurons in nigrostriatal pathway in the 6‐hydroxydopamine (6‐OHDA) unilaterally lesioned rats. Uric acid (UA), when given twice daily at 200 mg/kg intraperitoneally for 10 consecutive days, elevated urate (the anionic form of UA) in plasma and striatum by 55% and 36.8%, respectively, as compared with vehicle group. This regimen of UA was found to ameliorate the behavioral deficits, dopaminergic neuron loss as well as dopamine depletion in the nigrostriatal system. Moreover, UA administration was capable of increasing glutathione level and superoxide dismutase activity while decreasing malondialdehyde accumulation in striatum. In addition, the phosphorylation of both protein kinase B (Akt) and glycogen synthase kinase 3 beta (GSK3β) in the lesioned striata of 6‐OHDA‐lesioned rats was dramatically reduced as compared with sham‐operated rats. This reduction was attenuated in the Parkinsonian rats receiving UA treatment. Similarly, in vitro findings showed that UA alleviated the decrease in Akt activation and the increase in GSK3β activity caused by 6‐OHDA. Furthermore, neuroprotection by urate and its regulation on GSK3β phosphorylation at Ser9 was found to be abolished in the presence of PI3K inhibitor. Therefore, our findings demonstrated that urate was able to protect dopaminergic neurons in rat nigrostriatal pathway against the neurotoxicity of 6‐OHDA, and showed that its beneficial effects may be related to its regulation on Akt/GSK3β signaling.  相似文献   
965.
松辽盆地松科1井南孔晚白垩世介形类生物地层   总被引:2,自引:0,他引:2  
松科1井是世界上第一口陆相白垩纪科学钻井,其南孔获取自泉头组三段顶部至嫩江组二段底部的连续地层记录。本文以松科1井南孔岩心样品介形类化石的系统鉴定和统计分析为基础,共建立15个介形类化石组合带,自下而上分别为:1)C ypridea subtuberculis perga-Mongoloc ypris longicau...  相似文献   
966.
We studied [3H]N-[1-(2-thienyl)cyclohexyl]-3,4-piperidine [( 3H]TCP) binding to human frontal cortex obtained at autopsy from 10 histologically normal controls and eight histopathologically verified cases with Alzheimer-type dementia (ATD). Extensively washed membrane preparations were used to minimize the effects of endogenous substances. In ATD frontal cortex, the total concentration (Bmax) of [3H]TCP binding sites was significantly reduced by 40-50%. The apparent dissociation constant (KD) values showed no significant change. The reduction in binding capacity was also apparent in Triton X-100-treated membrane preparations, and there was a linear correlation between the number of [3H]TCP binding sites and that of N-methyl-D-aspartate (NMDA)-sensitive [3H]glutamate binding sites. [3H]TCP binding sites spared in ATD brains retained the affinity for the ligand and the reactivity to NMDA, L-glutamate, and glycine. These results suggest that the primary change in NMDA receptor-ion channel complex in ATD brains is the reduction of its number, possibly reflecting the loss of neurons bearing these receptor complexes, and that the functional linkage within the receptor complexes spared in ATD brains remains normal.  相似文献   
967.
Continued exposure of endothelial cells to mechanical/shear stress elicits the unfolded protein response (UPR), which enhances intracellular homeostasis and protect cells against the accumulation of improperly folded proteins. Cells commit to apoptosis when subjected to continuous and high endoplasmic reticulum (ER) stress unless homeostasis is maintained. It is unknown how endothelial cells differentially regulate the UPR. Here we show that a novel Girdin family protein, Gipie (78 kDa glucose-regulated protein [GRP78]-interacting protein induced by ER stress), is expressed in endothelial cells, where it interacts with GRP78, a master regulator of the UPR. Gipie stabilizes the interaction between GRP78 and the ER stress sensor inositol-requiring protein 1 (IRE1) at the ER, leading to the attenuation of IRE1-induced c-Jun N-terminal kinase (JNK) activation. Gipie expression is induced upon ER stress and suppresses the IRE1-JNK pathway and ER stress-induced apoptosis. Furthermore we found that Gipie expression is up-regulated in the neointima of carotid arteries after balloon injury in a rat model that is known to result in the induction of the UPR. Thus our data indicate that Gipie/GRP78 interaction controls the IRE1-JNK signaling pathway. That interaction appears to protect endothelial cells against ER stress-induced apoptosis in pathological contexts such as atherosclerosis and vascular endothelial dysfunction.  相似文献   
968.
Zhang  Haiju  Yu  Shiqian  Xia  Liping  Peng  Xia  Wang  Shun  Yao  Baozhen 《Neurochemical research》2022,47(3):713-722

Epilepsy (SE) is a common and serious neurological disease. NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome participates in the pathogenesis of SE, while its underlying mechanism is still unclear. Here, we attempted to explore the mechanism of action of NLRP3 inflammasome in SE. SE mouse model was constructed by administration of kainic acid (KA). Astrocytes were treated with KA to mimic SE cell model. MCC950 (NLRP3 inhibitor) and Z-YVAD-FMK (Caspase-1 inhibitor) were used to treat astrocytes to inhibit the activity of NLRP3 and Caspase-1. Nissl staining was performed to examine the morphology of neuron. Western blot, enzyme-linked immunosorbent assay and immunofluorescence staining were performed to assess protein expression. SE mouse model exhibited an increase of neuronal loss, and an up-regulation of Cleaved-Caspase-1, IL-1β and IL-18 in hippocampus. The levels of GFAP+ADK+ cells were significantly increased in SE mice. MCC950 or Z-YVAD-FMK abolished these impacts conferred by KA in SE mice. Moreover, KA treatment enhanced the expression of NLRP3, Cleaved-Caspase-1, IL-1β and IL-18 in astrocytes, which was rescued by knockdown of NLRP3 or Caspase-1. Additionally, CREB, p-CREB, REST were up-regulated, and SP1 was down-regulated in the KA-treated SE mice and KA-treated astrocytes. Inhibition of NLRP3 or Caspase-1 rescued these proteins expression in KA-treated astrocytes. CREB or REST silencing reduced adenosine kinase (ADK) expression, while SP1 knockdown enhanced ADK expression in KA-treated astrocytes. In conclusion, NLRP3 inflammasome activation enhances ADK expression to accelerate SE in mice through regulating CREB/REST/SP1 signaling pathway. Thus, inhibition of NLRP3 inflammasome may be a treatment for SE.

  相似文献   
969.
张思嘉  蔡挺  张顺 《生物信息学》2022,20(4):247-256
基于SNP突变数据与mRNA表达谱关联分析,构建一种肝癌分子分型方法并对比不同分型预后的差异,并对不同分型肝癌的发生发展机制进一步研究。首先通过TCGA数据库收集359例肝细胞癌患者的SNP突变数据和mRNA表达数据,采用Wilcoxon秩和检验,筛选突变后差异表达基因,并通过生物信息学工具String和Cytoscape构建差异表达基因的蛋白互作网络,筛选连接度最高的10个Hub基因。利用Consensus Cluster Plus软件包,基于Hub基因mRNA表达水平构建NMF分子分型模型,再结合生存数据评估各分型患者的预后。最后利用加权基因共表达网络分析(WGCNA),识别与肝癌分子分型相关的模块,并针对关键模块的基因进行通路富集,从而对不同分型肝癌的基因表达谱进行比较。结果:NMF模型将肝癌分为高危、低危2个分型,其中CDKN2A和FOXO1基因对分型贡献度高。生存分析显示低危组患者的生存情况显著优于高危组,高危组富集多个与肿瘤细胞侵蚀、转移、复发过程相关的信号通路,低危组则与细胞周期和胰液分泌相关。本研究在无先验性信息的前提下,基于突变后显著差异表达的Hub基因表达水平构建的...  相似文献   
970.
Diabetic cardiomyopathy is characterized by diabetes‐induced myocardial abnormalities, accompanied by inflammatory response and alterations in inflammation‐related signalling pathways. Kirenol, isolated from Herba Siegesbeckiae, has potent anti‐inflammatory properties. In this study, we aimed to investigate the cardioprotective effect of kirenol against DCM and underlying the potential mechanisms in a type 2 diabetes mellitus model. Kirenol treatment significantly decreased high glucose‐induced cardiofibroblasts proliferation and increased the cardiomyocytes viability, prevented the loss of mitochondrial membrane potential and further attenuated cardiomyocytes apoptosis, accompanied by a reduction in apoptosis‐related protein expression. Kirenol gavage could affect the expression of pro‐inflammatory cytokines in a dose‐dependent manner but not lower lipid profiles, and only decrease fasting plasma glucose, fasting plasma insulin and mean HbA1c levels in high‐dose kirenol‐treated group at some time‐points. Left ventricular dysfunction, hypertrophy, fibrosis and cell apoptosis, as structural and functional abnormalities, were ameliorated by kirenol administration. Moreover, in diabetic hearts, oral kirenol significantly attenuated activation of mitogen‐activated protein kinase subfamily and nuclear translocation of NF‐κB and Smad2/3 and decreased phosphorylation of IκBα and both fibrosis‐related and apoptosis‐related proteins. In an Electrophoretic mobility shift assay, the binding activities of NF‐κB, Smad3/4, SP1 and AP‐1 in the nucleus of diabetic myocardium were significantly down‐regulated by kirenol treatment. Additionally, high dose significantly enhanced myocardial Akt phosphorylation without intraperitoneal injection of insulin. Kirenol may have potent cardioprotective effects on treating for the established diabetic cardiomyopathy, which involves the inhibition of inflammation and fibrosis‐related signalling pathways and is independent of lowering hyperglycaemia, hyperinsulinemia and lipid profiles.  相似文献   
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