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991.
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
992.
993.
Shuo‐Guo Li Xiao‐Jun Huang Yuan‐Lin Zhong Man‐Mei Li Yao‐Lan Li Ying Wang Wen‐Cai Ye 《化学与生物多样性》2019,16(6)
Five new trans‐2,3,5,4′‐tetrahydroxystilbene 2‐O‐β‐d ‐glucopyranoside (TSG)‐based stilbene glycoside oligomers ( 1 – 5 ) were isolated from the roots of Polygonum multiflorum. Their structures were elucidated by comprehensive spectroscopic analyses and chemical evidences. The absolute configurations of 1 , 2 , 4 , and 5 were established by quantum‐chemical electronic circular dichroism (ECD) calculations. Putative biosynthetic pathways of 1–5 were proposed using TSG as the key precursor. In addition, compounds 1 (multiflorumiside H) and 3 (multiflorumiside J) exhibited moderate inhibitory activities against NO production in LPS‐stimulated RAW264.7 cells. 相似文献
994.
995.
Zhen‐Guo Yan Li‐Hang Xie Ning Wang Dao‐Yang Sun Zhang‐Zhen Bai Li‐Xin Niu Yan‐Long Zhang Xiao‐Tong Ji 《化学与生物多样性》2019,16(3)
Herbaceous peony has been widely cultivated in China due to its substantial ornamental and medicinal value. In the present study, the phenotypic characteristics, total fatty acid (FA) content, and nine FA compositions of herbaceous peony seeds from 14 populations belonging to six species and one subspecies were determined by normal test and gas chromatography/mass spectrometry (GC/MS). The results showed that the phenotypic characteristics of seeds varied dramatically among species. The concentrations of five major FAs in seed oils were as follows: linoleic acid (173.95–236.51 μg/mg), linolenic acid (227.82–302.71 μg/mg), oleic acid (135.32–208.81 μg/mg), stearic acid (6.52–11.7 μg/mg), and palmitic acid (30.67–47.64 μg/mg). Correlation analysis demonstrated that oleic acid had the highest partial correlation coefficient with total FAs and might be applied to develop a model of phenotypic characteristics. FAs were significantly influenced by the following environmental factors: latitude, elevation, and annual average temperature. Based on the FA levels in the seed oils, clustering analysis divided 14 populations into two clusters. It was found that the average contents of oleic acid, linoleic acid, and total FAs in cluster I (147.16 μg/mg, 200.31 μg/mg, and 671.24 μg/mg, respectively) were significantly lower than those in cluster II (196.65 μg/mg, 220.16 μg/mg, and 741.78 μg/mg, respectively). Cluster I was perfectly consistent with subsect. Foliolatae, while cluster II was in good agreement with subsect. Dissectifoliae. Therefore, the FA composition of wild herbaceous peony seed oil might be used as a chemotaxonomic marker. 相似文献
996.
Lifang Yang Jipeng Ma Ying Tan Qijun Zheng Maolong Dong Wei Guo Lize Xiong Jian Yang Jun Ren 《Journal of cellular and molecular medicine》2019,23(7):4640-4652
Hypertension contributes to the high cardiac morbidity and mortality. Although oxidative stress plays an essential role in hypertensive heart diseases, the mechanism remains elusive. Transgenic mice with cardiac overexpression of metallothionein, a heavy metal‐binding scavenger, were challenged with NG‐nitro‐L‐arginine methyl ester (L‐NAME) for 14 days prior to measurement of myocardial contractile and intracellular Ca2+ anomalies as well as cell signalling mechanisms using Western blot and immunofluorescence analysis. L‐NAME challenge elicited hypertension, macrophage infiltration, oxidative stress, inflammation and cardiac dysfunction manifested as increased proinflammatory macrophage marker F4/80, interleukin‐1β (IL‐1β), intracellular production, LV end systolic and diastolic diameters as well as depressed fractional shortening. L‐NAME treatment reduced mitochondrial membrane potential (MMP), impaired cardiomyocyte contractile and intracellular Ca2+ properties as evidenced by suppressed peak shortening, maximal velocity of shortening/relengthening, rise in intracellular Ca2+, along with elevated baseline and peak intracellular Ca2+. These unfavourable mechanical changes and decreased MMP (except blood pressure and macrophage infiltration) were alleviated by overexpression of metallothionein. Furthermore, the apoptosis markers including BAD, Bax, Caspase 9, Caspase 12 and cleaved Caspase 3 were up‐regulated while the anti‐apoptotic marker Bcl‐2 was decreased by L‐NAME treatment. Metallothionein transgene reversed L‐NAME‐induced changes in Bax, Bcl‐2, BAD phosphorylation, Caspase 9, Caspase 12 and cleaved Caspase 3. Our results suggest that metallothionein protects against L‐NAME‐induced myocardial contractile anomalies in part through inhibition of apoptosis. 相似文献
997.
Yong Wu Yu Deng Qinhao Guo Jun Zhu Lijie Cao Xueqi Guo Fei Xu Weiwei Weng Xingzhu Ju Xiaohua Wu 《Journal of cellular and molecular medicine》2019,23(8):5025-5036
Dysregulation of small nucleolar RNA host gene 6 (SNHG6) exerts critical oncogenic effects and facilitates tumourigenesis in human cancers. However, little information about the expression pattern of SNHG6 in ovarian clear cell carcinoma (OCCC) is available, and the contributions of this long non‐coding RNA to the tumourigenesis and progression of OCCC are unclear. In the present study, we showed via quantitative real‐time PCR that SNHG6 expression was abnormally up‐regulated in OCCC tissues relative to that in unpaired normal ovarian tissues. High SNHG6 expression was correlated with vascular invasion, distant metastasis and poor survival. Further functional experiments demonstrated that knockdown of SNHG6 in OCCC cells inhibited cell proliferation, migration and invasion in vitro as well as tumour growth in vivo. Moreover, SNHG6 functioned as a competing endogenous RNA (ceRNA), effectively acting as a sponge for miR‐4465 and thereby modulating the expression of enhancer of zeste homolog 2 (EZH2). Taken together, our data suggest that SNHG6 is a novel molecule involved in OCCC progression and that targeting the ceRNA network involving SNHG6 may be a treatment strategy in OCCC. 相似文献
998.
Yan Li Yiwei Cheng Tianyu Zhu Hao Zhang Wen Li Yueshuai Guo Yaling Qi Xu Chen Jun Zhang Jiahao Sha Zuomin Zhou Hui Zhu Xuejiang Guo 《Proteomics》2019,19(11)
The characteristic tadpole shape of sperm is formed from round spermatids via spermiogenesis, a process which results in dramatic morphological changes in the final stage of spermatogenesis in the testis. Protein phosphorylation, as one of the most important post‐translational modifications, can regulate spermiogenesis; however, the phosphorylation events taking place during this process have not been systematically analyzed. In order to better understand the role of phosphorylation in spermiogenesis, large‐scale phosphoproteome profiling is performed using IMAC and TiO2 enrichment. In total, 13 835 phosphorylation sites, in 4196 phosphoproteins, are identified in purified mouse spermatids undergoing spermiogenesis in two biological replicates. Overall, 735 testis‐specific proteins are identified to be phosphorylated, and are expressed at high levels during spermiogenesis. Gene ontology analysis shows enrichment of the identified phosphoproteins in terms of histone modification, cilium organization, centrosome and the adherens junction. Further characterization of the kinase‐substrate phosphorylation network demonstrates enrichment of phosphorylation substrates related to the regulation of spermiogenesis. This global protein phosphorylation landscape of spermiogenesis shows wide phosphoregulation across a diverse range of processes during spermiogenesis and can help to further characterize the process of sperm generation. All MS data are available via ProteomeXchange with the identifier PXD011890. 相似文献
999.
Nonaqueous metal–gas batteries based on halogenated reactants exhibit strong potential for future high‐energy electrochemical systems. The lithium–sulfur hexafluoride (Li–SF6) primary battery, which utilizes a safe, noncombustible, energy‐dense gas as cathode, demonstrates attractive eight‐electron transfer reduction during discharge and high attainable capacities (>3000 mAh g?1carbon) at voltages above 2.2 VLi. However, improved rate capability is needed for practical applications. Here, two viable strategies are reported to achieve this by targeting the solubility of the passivating discharge product, lithium fluoride (LiF). Operating at moderately elevated temperatures, e.g., 50 °C, in DMSO dramatically improves LiF solubility and promotes sparser and larger LiF nuclei on gas diffusion layer electrodes, leading to capacity improvements of ≈10× at 120 µA cm?2. More aggressive chemical modification of the electrolyte by including a tris(pentafluorophenyl)borane anion receptor further promotes LiF solubilization; capacity increases even at room temperature by a factor of 25 at 120 µA cm?2, with attainable capacities up to 3 mAh cm?2. This work shows that bulk fluoride‐forming conversion reactions can be strongly manipulated by tuning the electrolyte environment to be solvating toward F?, and that significantly improved rates can be achieved, leading a step closer to practical applications. 相似文献
1000.
Qing Zhang Christophe Didier Wei Kong Pang Yajie Liu Zhijie Wang Sean Li Vanessa K. Peterson Jianfeng Mao Zaiping Guo 《Liver Transplantation》2019,9(30)
Potassium‐ion batteries (PIBs) are an emerging, affordable, and environmentally friendly alternative to lithium‐ion batteries, with their further development driven by the need for suitably performing electrode materials capable of reversibly accommodating the relatively large K+. Layer‐structured manganese oxides are attractive as electrodes for PIBs, but suffer from structural instability and sluggish kinetics of K+ insertion/extraction, leading to poor rate capability. Herein, cobalt is successfully introduced at the manganese site in the KxMnO2 layered oxide electrode material and it is shown that with only 5% Co, the reversible capacity increases by 30% at 22 mA g‐1 and by 92% at 440 mA g‐1. In operando synchrotron X‐ray diffraction reveals that Co suppresses Jahn–Teller distortion, leading to more isotropic migration pathways for K+ in the interlayer, thus enhancing the ionic diffusion and consequently, rate capability. The detailed analysis reveals that additional phase transitions and larger volume change occur in the Co‐doped material as a result of layer gliding, with these associated with faster capacity decay, despite the overall capacity remaining higher than the pristine material, even after 500 cycles. These results assert the importance of understanding the detailed structural evolution that underpins performance that will inform the strategic design of electrode materials for high‐performance PIBs. 相似文献