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221.
目的:探讨白介素6(IL-6)在胶质母细胞瘤(GBM)中的表达,并探讨其高表达的作用机制,以期阐明GBM发生发展潜在分子机制。方法:采用免疫组化检测表皮生长因子变体3 (EGFRv III)阳性和阴性GBM组织IL-6的相对表达。以恶性胶质瘤细胞U87MG为研究对象,构建表达EGFRv III的U87MG-EGFRvIII细胞,用IL-1β分别处理U87MG、U87MG-EGFRvIII细胞,ELISA检测IL-6分泌量。采用EGFR下游效应通路p38MAPK、MK2、MEK1/2、JNK抑制剂SB、sc-48、PD、SP预处理细胞1小时,IL-1β刺激细胞后,检测各组IL-6分泌量变化。将IL-1β处理后的U87MG-EGFRvIII细胞记为IL-1β组,以不做任何处理细胞记为Control组,用联合SB、sc-48处理的IL-1β细胞依次命名为IL-1β+SB和IL-1β+sc-48组,western blot检测p38MAPK-MK2通路蛋白和IL-6蛋白表达,qPCR检测IL-6 m RNA表达。结果:IL-6在EGFRv III阳性GBM组织中普遍高表达,在EGFRv III阴性GBM组织中普遍低表达。EGFRv III可在未受IL-1β刺激的恶性胶质瘤细胞中上调IL-6基础分泌,也可在IL-1β刺激情况下进一步促进IL-6分泌。在U87MG细胞中,所有通路抑制剂对IL-6分泌均无影响;在U87MG-EGFRvIII细胞中p38 MAPK-MK2通路抑制剂SB和sc-48明显抑制IL-1β诱导的IL-6分泌,而MEK1/2、JNK抑制剂PD和SP则无明显影响。IL-1β能够诱导p38MAPK-MK2通路激活,诱导细胞内IL-6表达增加,联合SB、sc-48处理细胞后,p38MAPK-MK2通路活性降低,细胞内IL-6表达降低。结论:癌基因EGFRv III能够上调恶性胶质瘤细胞中IL-6基础分泌,IL-1β可进一步刺激IL-6分泌,其机制可能与p38MAPK-MK2通路激活有关。 相似文献
222.
黄绿卷毛菇(Floccularia luteovirens)是广泛分布于青藏高原高寒草甸的一种重要的可食用的菌根真菌。先前的研究利用EST-SSR引物已经对该物种的遗传多样性及群落结构进行了研究,但研究表明EST-SSR位点多态性较低,因此想要进一步探讨形成现有遗传分布格局的机制(该物种小尺度空间范围内基株的密度及大小)需要重新开发具有更高多态性的基于核基因的微卫星位点。本研究利用RAD测序技术使用直接测序分析的方法重新开发了12对具有多态性的引物。测序结果去接头拼装后共获得46 036条重叠群。在这些序列当中共扫描到342条含有重复单元的序列,在这当中70.47%为三碱基重复(241),8.19%为二碱基重复(28)。随机选取48对检测,12对具有多态性且测序结果良好,基于3个居群63个个体的遗传多样性研究显示,所有样品中共获得60个单倍型,每个位点的单倍型数量介于2 (GSSR26L)至9 (GSSR7L,GSSR11L)之间。Gst值介于-0.03(GSSR46L)至0.28(GSSR6L)之间、Fst值介于-0.03(GSSR33L)至0.42(GSSR6L)之间。在引物GSSR47L扩增测序中发现,其扩增出的片段不仅具有重复单元数量的变化,重复单元本身也存在突变的现象,这是之前使用聚丙烯凝胶电泳所检测不到的。本研究获得的微卫星引物将为接下来小尺度空间下研究黄绿卷毛菇基株的密度、大小及动态变化提供有力的支持。 相似文献
223.
Grafted embryonic central neural tissue pieces can recover function of hemisected spinal cord in neonatal rats and promote axonal growth in adults. However, spinal cord segments from adults have not been used as donor segments for allogeneic transplantation. Here, we utilized adult spinal cord tissue grafts(aSCGs) as donor constructs for repairing complete spinal cord injury(SCI). Moreover, to provide a favourable microenvironment for SCI treatment, a growth factor cocktail containing three growth factors(brain-derived neurotrophic factor, neurotrophin-3 and vascular endothelial growth factor), was applied to the aSCG transplants. We found that the locomotor function was significantly improved 12 weeks after transplantation of aSCGs into the spinal cord lesion site in adult rats. Transplantation of aSCGs combined with these growth factors enhanced neuron and oligodendrocyte survival and functional restoration. These encouraging results indicate that treatment of complete SCI by transplanting aSCGs, especially in the presence of growth factors, has a positive effect on motor functional recovery, and therefore could be considered as a possible therapeutic strategy for SCI. 相似文献
224.
QKI‐6 inhibits bladder cancer malignant behaviours through down‐regulating E2F3 and NF‐κB signalling
225.
Xiao‐Xia Pang Shun‐Da Luo Ting Zhang Feng Shi Chun‐Fang Wang Xing‐Hong Chen Yu‐Xia Wei Li Qin Jing‐Xi Wei Xiao‐Qiong Luo Jun‐Li Wang 《Journal of cellular and molecular medicine》2019,23(4):2410-2418
Interleukin‐27 (IL‐27) gene polymorphisms are linked to infectious disease susceptibility and IL‐27 plasma level is associated with HIV infection. Therefore, we aimed to investigate the association between IL‐27 polymorphisms and susceptibility to HIV infection and disease progression. A total of 300 patients with HIV infection (48 long‐term nonprogressors and 252 typical progressors) and 300 healthy controls were genotyped for three IL‐27 polymorphisms, rs17855750, rs181206, rs40837 which were performed by using multiple single nucleotide primer extension technique. Significant association was found between IL‐27 rs40837 polymorphisms with susceptibility to HIV infection (AG vs AA: adjusted OR = 1.60, 95% CI, 1.11‐2.30, P = 0.012; AG+GG vs AA: adjusted OR = 1.44, 95% CI, 1.02‐2.03, P = 0.038) and disease progression (LTNP: AG vs AA: adjusted OR = 2.33, 95% CI, 1.13‐4.80, P = 0.021; TP: AG vs AA: adjusted OR = 1.50, 95% CI, 1.04‐2.24, P = 0.030). Serum IL‐27 levels were significantly lower in cases compared to controls (P < 0.001). There were lower serum IL‐27 levels in TPs than in LTNPs (P < 0.001). We further found that LTNPs with rs40837 AG or GG genotype had lower serum IL‐27 levels than with AA genotype (P < 0.05). The CD4+T counts in cases were significantly lower than controls (P < 0.001). In contrast, individuals with rs40837 AG genotype had lower CD4+T counts than with AA genotype in cases (P < 0.05). In addition, CD4+T counts in TPs were significantly lower than LTNPs (P < 0.001). IL‐27 rs40837 polymorphism might influence the susceptibility to HIV infection and disease progression probably by regulating the level of serum IL‐27 or the quantity of CD4+T. 相似文献
226.
Jianing Tang Qiuxia Cui Dan Zhang Xing Liao Jian Zhu Gaosong Wu 《Journal of cellular and molecular medicine》2019,23(8):4980-4990
Quite a few estrogen receptor (ER)‐positive breast cancer patients receiving endocrine therapy are at risk of disease recurrence and death. ER‐related genes are involved in the progression and chemoresistance of breast cancer. In this study, we identified an ER‐related gene signature that can predict the prognosis of ER‐positive breast cancer patient receiving endocrine therapy. We collected RNA expression profiling from Gene Expression Omnibus database. An ER‐related signature was developed to separate patients into high‐risk and low‐risk groups. Patients in the low‐risk group had significantly better survival than those in the high‐risk group. ROC analysis indicated that this signature exhibited good diagnostic efficiency for the 1‐, 3‐ and 5‐year disease‐relapse events. Moreover, multivariate Cox regression analysis demonstrated that the ER‐related signature was an independent risk factor when adjusting for several clinical signatures. The prognostic value of this signature was validated in the validation sets. In addition, a nomogram was built and the calibration plots analysis indicated the good performance of this nomogram. In conclusion, combining with ER status, our results demonstrated that the ER‐related prognostic signature is a promising method for predicting the prognosis of ER‐positive breast cancer patients receiving endocrine therapy. 相似文献
227.
Xia Wei Chan Feng Xiao‐Hui Li Xing‐Xin Mao Hai‐Bin Luo Dong‐Mei Zhang Li Rong Zhen‐Yu Xie Xin Yu Jie Li Wen‐Cai Ye Xiao‐Jun Huang Cui‐Xian Zhang 《化学与生物多样性》2019,16(6)
One new racemic mixture, penicilliode A ( 1 ) and four pairs of enantiomeric polyketides, penicilliode B and C ( 2 and 3 ) and coniochaetone B and C ( 4 and 5 ), were obtained from the starfish‐derived symbiotic fungus Penicillium sp. GGF16‐1‐2. Interestingly, the strain GGF16‐1‐2 can produce enantiomers. The absolute configuration of 1 was determined by X‐ray diffraction (XRD) analysis, and the absolute configurations of 2 – 4 were determined by the optical rotation (OR) values and electronic circular dichroism (ECD) calculations. Compounds 1 – 5 were firstly isolated from the marine‐derived fungus Penicillium as racemates, and 2 – 5 were separated by HPLC with a chiral stationary phase. All the compounds were evaluated for their antibacterial, cytotoxic and inhibitory activities against PDE4D2. 相似文献
228.
Yiming An Xia Long Ming Ma Jue Hu He Lin Dan Zhou Zheng Xing Bolong Huang Shihe Yang 《Liver Transplantation》2019,9(41)
Currently, in addition to the electroactive non‐noble metal water‐splitting electrocatalysts, a scalable synthetic route and simple activity enhancement strategy is also urgently needed. In particular, the well‐controlled synthesis of the well‐recognized metal–metal nanointer face in a single step remains a key challenge. Here, the synthesis of Cu‐supported Ni4Mo nanodots on MoOx nanosheets (Ni4Mo/MoOx) with controllable Ni4Mo particle size and d‐band structure is reported via a facile one‐step electrodeposition process. Density functional theory (DFT) calculations reveal that the active open‐shell effect from Ni‐3d‐band optimizes the electronic configuration. The Cu‐substrate enables the surface Ni–Mo alloy dots to be more electron‐rich, forming a local connected electron‐rich network, which boosts the charge transfer for effective binding of O‐related species and proton–electron charge exchange in the hydrogen evolution reaction. The Cu‐supported Ni4Mo/MoOx shows an ultralow overpotential of 16 mV at a current density of 10 mA cm?2 in 1 m KOH, demonstrating the smallest overpotential, at loadings as low as 0.27 mg cm?2, among all non‐noble metal catalysts reported to date. Moreover, an overpotential of 105 mV allows it to achieve a current density of 250 mA cm?2 in 70 °C 30% KOH, a remarkable performance for alkaline hydrogen evolution with competitive potential for applications. 相似文献
229.
Xing Xu Hua Huo Jiyuan Jian Liguang Wang He Zhu Sheng Xu Xiaoshu He Geping Yin Chunyu Du Xueliang Sun 《Liver Transplantation》2019,9(15)
Ni‐rich Li[NixCoyMn1?x?y]O2 (x ≥ 0.8) layered oxides are the most promising cathode materials for lithium‐ion batteries due to their high reversible capacity of over 200 mAh g?1. Unfortunately, the anisotropic properties associated with the α‐NaFeO2 structured crystal grains result in poor rate capability and insufficient cycle life. To address these issues, a micrometer‐sized Ni‐rich LiNi0.8Co0.1Mn0.1O2 secondary cathode material consisting of radially aligned single‐crystal primary particles is proposed and synthesized. Concomitant with this unique crystallographic texture, all the exposed surfaces are active {010} facets, and 3D Li+ ion diffusion channels penetrate straightforwardly from surface to center, remarkably improving the Li+ diffusion coefficient. Moreover, coordinated charge–discharge volume change upon cycling is achieved by the consistent crystal orientation, significantly alleviating the volume‐change‐induced intergrain stress. Accordingly, this material delivers superior reversible capacity (203.4 mAh g?1 at 3.0–4.3 V) and rate capability (152.7 mAh g?1 at a current density of 1000 mA g?1). Further, this structure demonstrates excellent cycling stability without any degradation after 300 cycles. The anisotropic morphology modulation provides a simple, efficient, and scalable way to boost the performance and applicability of Ni‐rich layered oxide cathode materials. 相似文献
230.
目的:探讨重症监护病房(ICU)长期机械通气患者撤机困难的原因及撤机死亡的影响因素。方法:对2015年6月至2018年10月我院收治的80例长期机械通气患者的临床资料进行回顾性分析,按照患者撤机结果分为撤机成功组52例和撤机困难组28例,根据患者存活情况分为存活组59例和死亡组21例。比较各组临床资料,分析撤机困难的原因及撤机死亡的影响因素。结果:撤机困难组年龄、心功能不全比例、多器官功能障碍(MODS)比例、呼吸机相关肺炎(VAP)比例、肝功能不全比例、肾功能不全比例、血尿素氮显著高于撤机成功组,机械通气时间、气管切开时间显著长于撤机成功组,血清白蛋白显著低于撤机成功组(P0.05)。死亡组年龄、合并糖尿病比例、心功能不全比例、MODS比例、VAP比例、肝功能不全比例、肾功能不全比例、血尿素氮显著高于存活组,机械通气时间、气管切开时间显著长于存活组,血清白蛋白显著低于存活组(P0.05)。多因素Logistic回归分析显示:年龄、合并糖尿病、MODS、VAP、机械通气时间、气管切开时间、血清白蛋白是ICU长期机械通气患者撤机死亡的影响因素(P0.05)。结论:患者治疗期间发生脏器功能不全或器官功能衰竭、机械通气时间较长、气管切开时间较长、营养状态较差是长期机械通气患者撤机困难的主要原因,年龄、合并糖尿病、MODS、VAP、机械通气时间、气管切开时间、血清白蛋白是ICU长期机械通气患者撤机死亡的影响因素。 相似文献