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81.
82.
Glioblastoma multiforme (GBM) is the most common malignant tumour in the adult brain and hard to treat. Nuclear factor κB (NF‐κB) signalling has a crucial role in the tumorigenesis of GBM. EGFR signalling is an important driver of NF‐κB activation in GBM; however, the correlation between EGFR and the NF‐κB pathway remains unclear. In this study, we investigated the role of mucosa‐associated lymphoma antigen 1 (MALT1) in glioma progression and evaluated the anti‐tumour activity and effectiveness of MI‐2, a MALT1 inhibitor in a pre‐clinical GBM model. We identified a paracaspase MALT1 that is involved in EGFR‐induced NF‐kB activation in GBM. MALT1 deficiency or inhibition significantly affected the proliferation, survival, migration and invasion of GBM cells both in vitro and in vivo. Moreover, MALT1 inhibition caused G1 cell cycle arrest by regulating multiple cell cycle–associated proteins. Mechanistically, MALTI inhibition blocks the degradation of IκBα and prevents the nuclear accumulation of the NF‐κB p65 subunit in GBM cells. This study found that MALT1, a key signal transduction cascade, can mediate EGFR‐induced NF‐kB activation in GBM and may be potentially used as a novel therapeutic target for GBM.  相似文献   
83.
In order to find novel antitumor candidate agents with high efficiency and low toxicity, 14 novel substituted 5‐anilino‐α‐glucofuranose derivatives have been designed, synthesized and evaluated for antiproliferative activities in vitro. Their structures were characterized by NMR (1H and 13C) and HR‐MS, and configuration (R/S) at C(5) was identified by two‐dimensional 1H,1H‐NOESY‐NMR spectrum. Their antiproliferative activities against human tumor cells were investigated by MTT assay. The results demonstrated that most of the synthesized compounds had antiproliferative effects comparable to the reference drugs gefitinib and lapatinib. In particular, (5R)‐5‐O‐(3‐chloro‐4‐{[5‐(4‐fluorophenyl)thiophen‐2‐yl]methyl}anilino)‐5‐deoxy‐1,2‐O‐(1‐methylethylidene)‐α‐glucofuranose ( 9da ) showed the most potent antiproliferative effects against SW480, A431 and A549 cells, with IC50 values of 8.57, 5.15 and 15.24 μm , respectively. This work suggested 5‐anilino‐α‐glucofuranose as an antitumor core structure that may open a new way to develop more potent anti‐cancer agents.  相似文献   
84.
Ginseng and the seed of Zizyphus jujuba var. spinosa, which are traditional Chinese medicinal materials, were often used in ancient Chinese recipes as a pair of medicines. They can replenish the primordial qi and tonify the spleen. This study investigated the effects of ginseng and the seed of Zizyphus jujuba var. spinosa (GS) extract on gut microbiota diversity in rats with spleen deficiency syndrome (SDS). A total of 52 compounds (including 16 flavonoids, 35 saponins, and 1 alkaloid) were identified and analyzed from the GS extract by UPLC‐Q‐Orbitrap‐MS/MS. The GS extract significantly increased the relative abundance of Firmicutes and Bacteroidetes in rats with SDS but decreased that of Proteobacteria and Actinobacteria. At the genus level, the GS extract significantly increased the relative abundance of Lactobacillus and Bifidobacterium in rats with SDS but decreased that of Streptococcus, Escherichia‐Shigella, Veillonella, and Enterococcus. In addition, the GS extract influenced glucose and amino acid metabolism. In summary, the results showed that the GS extract changed the structure and diversity of gut microbiota in rats with SDS and balanced the metabolic process.  相似文献   
85.
Additives are widely adopted for efficient, stable, and hysteresis‐free perovskite solar cells and play an important role in various breakthroughs of perovskite solar cells (PSCs). Herein the various additives adopted for PSCs are reviewed and their functioning mechanism and influence on device performance is described. The main roles of additives, modulating morphology of perovskite films, stabilizing phase of formamidinium (FA) and cesium (Cs)‐based perovskites, adjusting energy level alignment in PSCs, suppressing nonradiative recombination in perovskites, eliminating hysteresis, enhancing operational stability of PSCs, are summarized.  相似文献   
86.
目的:研究白蛋白静脉滴注联合茵栀黄颗粒对新生儿黄疸血清碱性磷酸酶(alkaline phosphatase,AKP)、总胆汁酸(totalbileacids,TBA)、游离脂肪酸(free fatty acid,FFA)、γ-谷氨酰基转移酶(γ-glutamyltransferase,γ-GT)、超敏C-反应蛋白(hypersensitive C-reactive protein, HS-CRP)的影响。方法:选择2016年1月~2019年1月我院收治的95例新生儿病理性黄疸患儿,随机分为两组。对照组服用茵栀黄颗粒治疗,观察组在服用茵栀黄的基础上静脉滴注白蛋白治疗。检测两组的血清间接胆红素(indirectreacting bilirubin,,IBIL)、总胆红素(total bilirubin,TBIL)和AKP、TBA、FFA、y-GT、HS-CRP水平。结果:观察组的有效率明显高于对照组(P0.05);两组治疗后的血清IBIL、TBIL水平明显降低(P0.05),观察组的IBIL、TBIL水平明显低于对照组(P0.05);两组治疗后的血清AKP、TBA、FFA、γ-GT、HS-CRP水平明显降低(P0.05),观察组的血清AKP、TBA、FFA、γ-GT、HS-CRP水平明显低于对照组(P0.05)。结论:白蛋白静脉滴注联合茵栀黄颗粒对新生儿黄疸的治疗效果良好,有助于促进血清胆红素和其他血清学相关指标恢复正常,且安全性好。  相似文献   
87.
目的:探讨门冬胰岛素联合甘精胰岛素对新诊断2型糖尿病患者血清炎性因子、血糖及血脂水平的影响。方法:选取我院2017年3月~2019年3月收治的100例新诊断2型糖尿病患者,将其随机分为研究组和对照组,每组50例患者。对照组患者给予门冬胰岛素治疗,研究组患者给予门冬胰岛素联合甘精胰岛素治疗,对比两组患者治疗前后血清炎性因子、血糖及血脂水平的变化。结果:治疗后,两组患者糖化血红蛋白(hemoglobin A1c,HbA1c)、空腹血糖(fasting plasma glucose,FPG)、餐后2h血糖(2h postprandial blod glucose,2hPBG)、血清肿瘤坏死因子(Tumor necrosis factor,TNF-α)、高敏C反应蛋白(high-sensitive C-reactive protein,hs-CRP)水平均较治疗前明显降低(P0.05),且研究组患者以上指标均显著低于对照组(P0.05);两组患者治疗后总胆固醇(Total Cholesterol,TC)、甘油三酯(Triglyceride,TG)、低密度脂蛋白胆固醇(Low-density lipoprotein cholesterol,LDL-C)水平均较治疗前明显降低,高密度脂蛋白胆固醇(High-density lipoprotein cholesterol,HDL-C)明显升高(P0.05),且研究组以上指标的改善程度均优于对照组(P0.05)。研究组患者的胰岛素用量明显少于对照组(P0.05),患者血糖首次达标时间明显短于对照组(P0.05)。结论:门冬胰岛素联合甘精胰岛素适用于新诊断2型糖尿病患者,可有效降低血糖、血脂、血清TNF-α和hs-CRP水平。  相似文献   
88.
Niu  Lili  Guo  Yanchen  Lin  Zhengrong  Shi  Zhe  Bian  Tianyuan  Qi  Lin  Meng  Long  Grace  Anthony A.  Zheng  Hairong  Yuan  Ti-Fei 《中国科学:生命科学英文版》2020,63(9):1328-1336
Ultrasound stimulation is an emerging noninvasive option in treating neuropsychiatric disorders. The present study investigates the behavioral alterations resulting from ultrasound stimulation on the nucleus accumbens(NAc) in freely moving mice. Our results show that an acute ultrasound stimulation on the NAc, rather than the visual cortex or auditory cortex, led to a pronounced avoidance behavior, while repeated NAc ultrasound stimulation resulted in an obvious conditioned place aversion with changes in synaptic protein(Glu A1/2 subunit) expression. Notably, NAc ultrasound stimulation suppressed the morphine-induced conditioned place preference. The results provide evidence that NAc ultrasound stimulation can be applied as a potential noninvasive therapeutic option in treating psychiatric disorders.  相似文献   
89.
本研究通过比较9个内参基因在山羊不同组织中的表达水平进而确定最适合研究山羊组织表达的内参基因。本试验以简州大耳羊为试验材料,利用实时荧光定量PCR技术分析9个内参基因(GAPDH,PPIA,18S rRNA,PPIB,UXT,RPLP0,ACTB,EIF3K和TBP)在心脏、肝脏、脾脏、肺脏、肾脏、大肠、瘤胃、背最长肌和皮下脂肪等组织中的表达差异情况,并利用geNorm、NormFinder和BestKeeper等程序分析了它们的表达稳定性。geNorm和NormFinder程序一致显示TBP表达最稳定,其次是UXT和RPLP0;BestKeeper分析显示18S rRNA表达最为稳定,其次为TBP和ACTB;3个程序一致认为GAPDH表达稳定性最差。综合3个程序分析得出TBP最适合作为山羊组织中的内参基因,其次为UXT和RPLP0,GAPDH表达稳定性最差,不适合作为山羊组织内参,这为后续研究其他目的基因在山羊组织器官中的表达模式提供数据保障。  相似文献   
90.
Saccharomyces cerevisiae is the preferred source of RNA derivatives, which are widely used as supplements for foods and pharmaceuticals. As the most abundant RNAs, the ribosomal RNAs (rRNAs) transcribed by RNA polymerase I (Pol I) have no 5′ caps, thus cannot be translated to proteins. To screen high-nucleic-acid content yeasts more efficiently, a cap-independent protein expression system mediated by Pol I has been designed and established to monitor the regulatory changes of rRNA synthesis by observing the variation in the reporter genes expression. The elements including Pol I-recognized rDNA promoter, the internal ribosome entry site from cricket paralytic virus which can recruit ribosomes internally, reporter genes (URA3 and yEGFP3), oligo-dT and an rDNA terminator were ligated to a yeast episomal plasmid. This system based on the URA3 gene worked well by observing the growth phenotype and did not require the disruption of cap-dependent initiation factors. The fluorescence intensity of strains expressing the yEGFP3 gene increased and drifted after mutagenesis. Combined with flow cytometry, cells with higher GFP level were sorted out. A strain showed 58% improvement in RNA content and exhibited no sequence alteration in the whole expression cassette introduced. This study provides a novel strategy for breeding high-nucleic-acid content yeasts.  相似文献   
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