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961.
为检测IARS2和MYO5B在胃癌组织中的表达并探讨IARS2表达与胃癌患者临床病理特征及预后的关系,本研究使用荧光定量PCR (quantitative polymerase chain reaction, qRT-PCR)及Western blotting检测30例胃癌组织和癌旁组织中IARS2和MYO5B的表达,使用线性回归分析两者m RNA表达相关性。使用免疫组化方法检测86对胃癌组织及癌旁组织中IARS2蛋白的表达情况,根据免疫组化IARS2表达情况将胃癌患者分为IARS2阳性组和阴性组,比较两组患者临床病理特征及预后情况。结果发现,较之癌旁组织,IASR2在胃癌组织中显著高表达(p<0.05),而MYO5B在胃癌组织中显著低表达(p<0.05),且两者表达负相关(r=0.5768, p=0.0008)。免疫组化显示IASR2阳性细胞在胃癌组织中的阳性率为70.9%。IASR2高表达提示更高的胃癌淋巴结转移(p=0.041)和TNM分期(p=0.004)及更低的患者术后5年总生存率(p=0.000 6)。研究提示IARS2在胃癌组织中高表达,可作为评估胃癌预后的标志物。 相似文献
962.
963.
Ying Kong Yan Gao Dongyi Lan Ying Zhang Rixin Zhan Meiqi Liu Zhouan Zhu Guohua Zeng Qiren Huang 《Journal of cellular and molecular medicine》2019,23(1):216-226
Previous study has shown that thiazolidinediones (TZDs) improved endothelium insulin resistance (IR) induced by high glucose concentration (HG)/hyperglycaemia through a PPARγ‐dependent‐NFκB trans‐repression mechanism. However, it is unclear, whether changes in PPARγ expression affect the endothelium IR and what the underlying mechanism is. In the present study, we aimed to address this issue. HG‐treated human umbilical vascular endothelial cells (HUVEC) were transfected by either PPARγ‐overexpressing (Ad‐PPARγ) or PPARγ‐shRNA‐containing (Ad‐PPARγ‐shRNA) adenoviral vectors. Likewise, the rats fed by high‐fat diet (HFD) were infected by intravenous administration of Ad‐PPARγ or Ad‐PPARγ‐shRNA. The levels of nitric oxide (NO), endothelin‐1 (ET‐1) and cytokines (TNFα, IL‐6, sICAM‐1 and sVCAM‐1) and the expression levels of PPARγ, eNOS, AKT, p‐AKT, IKKα/β and p‐IKKα/β and IκBα were examined; and the interaction between PPARγ and NFκB‐P65 as well as vascular function were evaluated. Our present results showed that overexpression of PPARγ notably increased the levels of NO, eNOS, p‐AKT and IκBα as well as the interaction of PPARγ and NFκB‐P65, and decreased the levels of ET‐1, p‐IKKα/β, TNFα, IL‐6, sICAM‐1 and sVCAM‐1. In contrast, down‐expression of PPARγ displayed the opposite effects. The results demonstrate that the overexpression of PPARγ improves while the down‐expression worsens the endothelium IR via a PPARγ‐mediated NFκB trans‐repression dependent manner. The findings suggest PPARγ is a potential therapeutic target for diabetic vascular complications. 相似文献
964.
965.
Da Sun Jia Chen Wei Wu Ju Tang Li Luo Kun Zhang Libo Jin Sue Lin Yitian Gao Xiaoqing Yan Chi Zhang 《Journal of cellular and molecular medicine》2019,23(4):2863-2871
Obesity is associated with significant microvascular complications including renal injuries and may induce end‐stage renal disease. Emerging studies have demonstrated microRNAs (miRNAs) are potential mediators in the pathophysiological process of nephropathy. The present study aimed to investigate the role of miR‐802 in obesity‐related nephropathy and potential molecular mechanisms. Through utilizing obese mouse model and human subjects, we explored the therapeutic benefits and clinical application of miR‐802 in protecting against nephropathy. Renal miR‐802 level was positively correlated with functional parameters, including blood urea nitrogen and creatinine in obese mice. Specific silencing of renal miR‐802 improved high fat diet (HFD)‐induced renal dysfunction, structural disorders and fibrosis. The up‐regulated inflammatory response and infiltrated macrophages were also significantly decreased in miR‐802 inhibitor‐treated obese mice. Mechanistically, miR‐802 directly bond to 3?‐UTR of NF‐κB‐repressing factor (NRF) and suppressed its expression. In clinical study, the circulating miR‐802 level was significantly increased in obese subjects, and positively correlated with plasma creatinine level but negatively correlated with creatinine clearance. Taken together, our findings provided evidence that miR‐802/NRF signalling was an important pathway in mediating obesity‐related nephropathy. It is a possible useful clinical approach of treating miR‐802 inhibitor to combat nephropathy. 相似文献
966.
Qiaojuan Zhu Yazhao Li Yang Guo Linjun Hu Zunqiang Xiao Xin Liu Jiahui Wang Qiuran Xu Xiangmin Tong 《Journal of cellular and molecular medicine》2019,23(11):7395-7405
The aberrant expression and dysfunction of long non‐coding RNAs (lncRNAs) have been identified as critical factors governing the initiation and progression of different human cancers, including diffuse large B‐cell lymphoma (DLBCL). LncRNA small nucleolar RNA host gene 16 (SNHG16) has been recognized as a tumour‐promoting factor in various types of cancer. However, the biological role of SNHG16 and its underlying mechanism are still unknown in DLBCL. Here we disclosed that SNHG16 was overexpressed in DLBCL tissues and the derived cell lines. SNHG16 knockdown significantly suppressed cell proliferation and cell cycle progression, and it induced apoptosis of DLBCL cells in vitro. Furthermore, silencing of SNHG16 markedly repressed in vivo growth of OCI‐LY7 cells. Mechanistically, SNHG16 directly interacted with miR‐497‐5p by acting as a competing endogenous RNA (ceRNA) and inversely regulated the abundance of miR‐497‐5p in DLBCL cells. Moreover, the proto‐oncogene proviral integration site for Moloney murine leukaemia virus 1 (PIM1) was identified as a novel direct target of miR‐497‐5p. SNHG16 overexpression rescued miR‐497‐5p‐induced down‐regulation of PIM1 in DLBCL cells. Importantly, restoration of PIM1 expression reversed SNHG16 knockdown‐induced inhibition of proliferation, G0/G1 phase arrest and apoptosis of OCI‐LY7 cells. Our study suggests that the SNHG16/miR‐497‐5p/PIM1 axis may provide promising therapeutic targets for DLBCL progression. 相似文献
967.
Claudia Karnthaler‐Benbakka Bettina Koblmüller Marlene Mathuber Katharina Holste Walter Berger Petra Heffeter Christian R. Kowol Bernhard K. Keppler 《化学与生物多样性》2019,16(1)
Since several decades, the prodrug concept has raised considerable interest in cancer research due to its potential to overcome common problems associated with chemotherapy. However, for small‐molecule tyrosine kinase inhibitors, which also cause severe side effects, hardly any strategies to generate prodrugs for therapeutic improvement have been reported so far. Here, we present the synthesis and biological investigation of a cathepsin B‐cleavable prodrug of the VEGFR inhibitor sunitinib. Cell viability assays and Western blot analyses revealed, that, in contrast to the non‐cathepsin B‐cleavable reference compound, the prodrug shows activity comparable to the original drug sunitinib in the highly cathepsin B‐expressing cell lines Caki‐1 and RU‐MH. Moreover, a cathepsin B cleavage assay confirmed the desired enzymatic activation of the prodrug. Together, the obtained data show that the concept of cathepsin B‐cleavable prodrugs can be transferred to the class of targeted therapeutics, allowing the development of optimized tyrosine kinase inhibitors for the treatment of cancer. 相似文献
968.
Jiaojiao Deng Xiaoliang Yu Xianying Qin Dong Zhou Lihan Zhang Huan Duan Feiyu Kang Baohua Li Guoxiu Wang 《Liver Transplantation》2019,9(14)
Transition metal oxides hold great promise as high‐energy anodes in next‐generation lithium‐ion batteries. However, owing to the inherent limitations of low electronic/ionic conductivities and dramatic volume change during charge/discharge, it is still challenging to fabricate practically viable compacted and thick TMO anodes with satisfactory electrochemical performance. Herein, with mesoporous cobalt–boride nanoflakes serving as multifunctional bridges in ZnCo2O4 micro‐/nanospheres, a compacted ZnCo2O4/Co–B hybrid structure is constructed. Co–B nanoflakes not only bridge ZnCo2O4 nanoparticles and function as anchors for ZnCo2O4 micro‐/nanospheres to suppress the severe volume fluctuation, they also work as effective electron conduction bridges to promote fast electron transportation. More importantly, they serve as Li+ transfer bridges to provide significantly boosted Li+ diffusivity, evidenced from both experimental kinetics analysis and density functional theory calculations. The mesopores within Co–B nanoflakes help overcome the large Li+ diffusion barriers across 2D interfaces. As a result, the ZnCo2O4/Co–B electrode delivers high gravimetric/volumetric/areal capacities of 995 mAh g?1/1450 mAh cm?3/5.10 mAh cm?2, respectively, with robust rate capability and long‐term cyclability. The distinct interfacial design strategy provides a new direction for designing compacted conversion‐type anodes with superior lithium storage kinetics and stability for practical applications. 相似文献
969.
《Harmful algae》2019
Cyanobacterial blooms occur when algal densities exceed baseline population concentrations. Cyanobacteria can produce a large number of secondary metabolites. Odorous metabolites affect the smell and flavor of aquatic animals, whereas bioactive metabolites cause a range of lethal and sub-lethal effects in plants, invertebrates, and vertebrates, including humans. Herein, the bioactivity, chemistry, origin, and biosynthesis of these cyanobacterial secondary metabolites were reviewed. With recent revision of cyanobacterial taxonomy by Anagnostidis and Komárek as part of the Süβwasserflora von Mitteleuropa volumes 19(1–3), names of many cyanobacteria that produce bioactive compounds have changed, thereby confusing readers. The original and new nomenclature are included in this review to clarify the origins of cyanobacterial bioactive compounds.Due to structural similarity, the 157 known bioactive classes produced by cyanobacteria have been condensed to 55 classes. This review will provide a basis for more formal procedures to adopt a logical naming system. This review is needed for efficient management of water resources to understand, identify, and manage cyanobacterial harmful algal bloom impacts. 相似文献
970.
目的:探讨皮下种植黑色素瘤对小鼠血液中相关脂肪和氨基酸代谢的影响。方法:野生型小鼠皮下种植B16黑色素瘤细胞,两周后观察小鼠并取不同的组织称重,检测血液中甘油三酯、葡萄糖、脂肪酸、炎症因子的水平。利用质谱方法检测血液中氨基酸的水平。结果:野生型小鼠皮下肿瘤种植2周后体重没有明显变化,脾脏和肝脏的重量明显增加,皮下脂肪组织和腹腔脂肪组织的重量没有明显变化。血液中甘油三酯的水平明显增高,葡萄糖和甘油的水平明显下降。血液中炎症因子Interleukin 6(IL6)和Interferon gamma(IFNγ)的水平明显增加。血液的质谱结果显示有四种氨基酸的水平有明显变化,其中胱氨酸(Cystine)增加了约30倍,丝氨酸(Serine)、谷氨酰胺(Glutamine)和色氨酸(Tryptophan)分别有不同程度的降低。结论:皮下黑色素瘤显著影响小鼠机体营养状态和炎症,并特异性影响血液中氨基酸的代谢。 相似文献