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21.
JunDan Wang JueQiong Xu XueNing Zhang ZeWei Huang LingLing Liu Ling Zhang XinXing Lei ManJie Xue JianYu Weng ZiJie Long 《Cell proliferation》2022,55(12)
ObjectivesMutant C/EBPα p30 (mp30), the product of C/EBPα double mutations (DM), lacks transactivation domain 1 and has C‐terminal loss‐of‐function mutation. Acute myeloid leukaemia (AML) patients harbouring C/EBPα DM could be classified as a distinct subgroup with favourable prognosis. However, the underlying mechanism remains elusive.Materials and MethodsAutophagy regulated by mp30 was detected by western blot and immunofluorescence. Immune infiltration analysis and GSEA were performed to investigate autophagic and inflammatory status of AML patients from the cohort. Flow cytometry was applied to analyse T cell activation.ResultsMp30 inhibited autophagy by suppressing nucleus translocation of NF‐κB. Autophagy‐associated secretion of IL‐1β was decreased in mp30‐overexpressed AML cells. Bioinformatic analysis revealed that inflammatory status was attenuated, while CD8+ T cell infiltration was upregulated in C/EBPα DM AML patients. Consistently, the proportion of CD8+CD69+ T cells in peripheral blood mononuclear cells (PBMCs) was upregulated after co‐culture with mp30 AML cell conditional culture medium. Knock‐out of IL‐1β in AML cells also enhanced CD8+ T cell activation. Accordingly, IL‐1β expression was significantly reduced in the bone marrow (BM) cells of C/EBPα DM AML patients compared to the wildtype, while the CD8+CD69+ T cell proportion was specifically elevated.ConclusionsC/EBPα DM alleviates immunosuppression of CD8+ T cells by inhibiting the autophagy‐associated secretion of IL‐1β, which elucidated that repression of autophagy‐related inflammatory response in AML patients might achieve a favourable clinical benefit.Mp30 suppresses autophagy‐associated IL‐β secretion, which ultimately alleviates the immunosuppression of CD8+ T cells in the microenvironment, contributing to favourable prognosis of AML patients. GSE14468相似文献
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23.
Weng Y Lu J Xiang L Matsuura A Zhang Y Huang Q Qi J 《Bioscience, biotechnology, and biochemistry》2011,75(4):800-803
Two new anti-aging compounds, ganodermasides C and D, were isolated and their structures elucidated. They are novel ergosterols possessing a 4,6,8(14),22-tetraene-3-one unit with unique hydroxylation at C-9. Both of them significantly extended the replicative lifespan of the K6001 yeast strain. Ganodermasides C and D regulated the expression of the gene for UTH1 to prolong the replicative lifespan of yeast. 相似文献
24.
植被(包括天然植被、人工植被)作为一种可更新资源始终是遥感应用专家们热心研究的课题。植被分类是植被研究的重要方面之一。利用卫星影象进行植被分类,国内外学者都进行了许多有意义的探索。本文以洞庭湖水域、洲滩植被为对象,试用卫星影象进行植被分类。本文从植被与环境相互依赖关系及在影象上的综合反映出发,提出了影象的景观生态学分析方法;即把影象上色调、形态特征与群落生态学规律结合起来分析,并以此作为植被目视解译的方法。在此基础上,将洞庭湖水域、洲滩划分成五个景观生态模型,17个基本植被类型。 相似文献
25.
Rosie A. Fisher Charles D. Koven William R. L. Anderegg Bradley O. Christoffersen Michael C. Dietze Caroline E. Farrior Jennifer A. Holm George C. Hurtt Ryan G. Knox Peter J. Lawrence Jeremy W. Lichstein Marcos Longo Ashley M. Matheny David Medvigy Helene C. Muller‐Landau Thomas L. Powell Shawn P. Serbin Hisashi Sato Jacquelyn K. Shuman Benjamin Smith Anna T. Trugman Toni Viskari Hans Verbeeck Ensheng Weng Chonggang Xu Xiangtao Xu Tao Zhang Paul R. Moorcroft 《Global Change Biology》2018,24(1):35-54
Numerous current efforts seek to improve the representation of ecosystem ecology and vegetation demographic processes within Earth System Models (ESMs). These developments are widely viewed as an important step in developing greater realism in predictions of future ecosystem states and fluxes. Increased realism, however, leads to increased model complexity, with new features raising a suite of ecological questions that require empirical constraints. Here, we review the developments that permit the representation of plant demographics in ESMs, and identify issues raised by these developments that highlight important gaps in ecological understanding. These issues inevitably translate into uncertainty in model projections but also allow models to be applied to new processes and questions concerning the dynamics of real‐world ecosystems. We argue that stronger and more innovative connections to data, across the range of scales considered, are required to address these gaps in understanding. The development of first‐generation land surface models as a unifying framework for ecophysiological understanding stimulated much research into plant physiological traits and gas exchange. Constraining predictions at ecologically relevant spatial and temporal scales will require a similar investment of effort and intensified inter‐disciplinary communication. 相似文献
26.
A novel thin film ethanol sensor using sputtered Ni/Pt/Ti on an Al2O3 substrate as the working electrode in an alkaline solution was developed. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to characterize the nanostructure of nickel films. Sputtering deposition conditions for maximum catalytic efficiency, electrode selectivity, and reproducibility were discussed. The results showed that ethanol oxidation was more efficient on the sputtered Ni/Pt/Ti on an Al2O3 substrate electrode than that on the conventional nickel electrode. The optimal operating conditions to generate the sputtered Ni/Pt/Ti on the Al2O3 substrate electrode were: 45 min of Ni sputtering deposition time, and 50 W of Ni sputtering power. The results also indicated that the response time of the prepared ethanol sensor is 27 s and the best sensitivity is 3.08 microA microM(-1) cm(-2). 相似文献
27.
双向凝胶电泳-飞行时间质谱技术鉴定小鼠胚泡黏附时子宫内膜nm23-M2/NDPK B的表达 总被引:3,自引:0,他引:3
运用双向聚丙烯酰胺凝胶电泳(2DPAGE)分析未交配小鼠子宫内膜和妊娠第五天(D5)小鼠子宫内膜胚泡黏附时植入位点及其旁组织蛋白质组。差异蛋白质组学显示,等电点(isoelectric point,pI)约7.1、分子量(molecular weight,Mw)约18kDa的蛋白质点在D5小鼠子宫内膜特别是植入位点表达上调。对此蛋白质点用基质辅助激光解析电离飞行时间质谱(matrix-assisted laser desorption/ionization time of flying mass spectrometry,MALDI—TOF—MS)测定其胶内酶解后的肽质量指纹谱(Peptide Mass Fingerprint,PMF),经Mascot:Peptide Mass Fingerprint中SWISS-PROT数据库查询后,鉴定该蛋白质为鼠源性nm23-M2/NDPKB。RT—PCR和免疫组织化学结果也显示D5小鼠子宫内膜nm23-M2/NDPK B mRNA和蛋白表达明显增加。提示nm23-M2/NDPKB参与胚泡着床这一重要生命活动过程。 相似文献
28.
Hsu HH Cheng SF Wu CC Chu CH Weng YJ Lin CS Lee SD Wu HC Huang CY Kuo WW 《The Chinese journal of physiology》2006,49(2):110-116
Epidemiologic studies reported that the prevalence of hereditary non-polyposis colon cancer (HNPCC) in male is about 1.5-fold higher than that in female. Decreases in circulatory estradiol (E2) have been reported to downregulate the expression of E2 receptor (ER) and significantly increase the risk of colorectal cancer. Patients that received E2 replacement therapy were found to have a reduction in the incidence of colon adenoma and carcinoma. Furthermore, significant decreases in the expression of ER have been found in colorectal cancer specimens. These data strongly suggest the protective roles of E2 and ER against colorectal cancer. However, the mechanisms remain unexplored. LoVo cells were transient transfected to overexpress ER-beta, DNA fragmentation and caspase activity assay were performed to evaluate apoptotic effects. Western blotting was used to evaluate protein levels, and luciferase activity assay to measure the TNF-alpha promoter activity. Our data clearly demonstrated that E2 and ER-beta alone could upregulate p21 and p27 proteins, which further activate caspase-8 and caspase-9 to induce apoptosis in LoVo cell, and the ER-beta. effects were enhanced by E2. However, overexpressed ER-beta did not influence the expression and promoter activity of TNF-alpha. In addition, E2 and overexpressed ER-beta downregulated the beta-catenin proteins which cause the downregulation of its target genes, cyclin D1 and Rb, to inhibit the cell cycle and cell proliferation. The results indicate that overexpressed ER-beta may induce LoVo cell apoptosis and anti-proliferation by increasing p53 signaling in a ligand-dependent manner, and without hTNF-alpha involvement. Efforts aiming at enhancing ER-beta expression and/or activity may prove to be an attractive alternative therapy against colorectal cancer. 相似文献
29.
Enzyme immobilization for biodiesel production 总被引:1,自引:0,他引:1
Biodiesel has attracted more and more attention in recent years because of its biodegradability, environmentally friendliness,
and renewability. Contrary to the conventional chemical catalysis method to produce biodiesel, the biochemical catalysis method
developed quickly in the past decade and many immobilized enzymes are commercially available to meet the large-scale industrialization
of biodiesel. This review is focusing on the current status of biodiesel production by biochemical catalysis method, especially
the commercial enzyme and its immobilization for biodiesel production. Consequently, we believe that biochemical catalysis
with immobilized enzymes is bound to be an alternative method instead of chemical catalysis in biodiesel production in the
near future. 相似文献
30.
添加外源锌对大杯香菇子实体细胞保护酶活性的影响 总被引:3,自引:0,他引:3
摘要:【目的】本实验研究了添加外源锌(Zn)对大杯香菇子实体保护酶活性的影响。【方法】以硫酸锌为外源锌,添加到培养料中,制成0、10、20、30、40、50 mg/kg 6个浓度。采用分光光度法测定大杯香菇子实体超氧化物岐化酶(SOD)活性、过氧化物酶(POD)活性、多酚氧化酶(PPO)活性、丙二醛(MDA)含量和可溶性蛋白含量,采用高锰酸钾滴定法过氧化氢酶(CAT)活性。【结果】添加外源 Zn浓度为30 mg/kg处理大杯香菇子实体内可溶性蛋白含量、SOD、POD和CAT活性极显著提高(P<0.01),PPO活性极显著减少(P<0.01),而MDA含量显著下降(P<0.05)。随着Zn水平进一步升高,可溶性蛋白含量、SOD、POD和CAT活性呈下降趋势,而MDA含量极显著和显著上升(P<0.01和P<0.05)。【结论】高用量的Zn浓度能使大杯香菇子实体中的MDA含量上升,SOD、POD、CAT活性均下降,对保护酶系统有破坏作用,促进自由基的积累,从而导致膜脂过氧化作用的加剧。适宜Zn浓度能提高保护酶的活性,从而抑制了大杯香菇子实体中细胞膜脂过氧化水平,减轻膜伤害。 相似文献