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81.
Long noncoding RNAs (lncRNAs) have been proved to play important roles in carcinogenesis and development of numerous cancers, but their biological functions in bladder cancer remain largely unknown. In this study, a novel lncRNA termed GAS6‐AS2 were primary identified, and its roles as well as mechanisms in regulating proliferation and metastasis of bladder cancer cells were investigated. Clinically, GAS6‐AS2 was significantly up‐regulated in bladder cancer tissues and positively correlated with tumour stages and poor prognosis. Moreover, expression of GAS6‐AS2 was also increased in bladder cancer cells compared with normal bladder cells. Further investigating the roles of GAS6‐AS2, we found GAS6‐AS2 regulated proliferation and proliferative activity of bladder cancer cells via inducing G1 phase arrest. What's more, we found that GAS6‐AS2 contributed to metastatic abilities of cells. In mechanism, GAS6‐AS2 could function as a competitive endogenous RNA (ceRNA) via direct sponging miR‐298, which further regulating the expression of CDK9. Finally, we also proved that GAS6‐AS2 knockdown suppressed tumour growth and metastasis in vivo. In conclusion, our study proved that GAS6‐AS2 could function as a ceRNA and promote the proliferation and metastasis of bladder cancer cells, which provided a novel prognostic marker for bladder cancer patients in clinic.  相似文献   
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83.
Solar‐driven water splitting is in urgent need for sustainable energy research, for which accelerating oxygen evolution kinetics along with charge migration is the key issue. Herein, Mn3+ within π‐conjugated carbon nitride (C3N4) in form of Mn–N–C motifs is coordinated. The spin state (eg orbital filling) of Mn centers is regulated by controlling the bond strength of Mn–N. It is demonstrated that Mn serves as intrinsic oxygen evolution reaction (OER) site and the kinetics is dependent on its spin state with an optimized eg occupancy of ≈0.95. Specifically, the governing role of eg occupancy originates from the varied binding strength between Mn and OER intermediates. Benefiting from the rapid spin state‐mediated OER kinetics, as well as extended optical absorption (to 600 nm) and accelerated charge separation by intercalated metal‐to‐ligand state, Mn–C3N4 stoichiometrically splits pure water with H2 production rate up to 695.1 µmol g?1 h?1 under simulated sunlight irradiation (AM1.5), and achieves an apparent quantum efficiency of 4.0% at 420 nm, superior to most solid‐state based photocatalysts to date. This work for the first time correlates photocatalytic redox kinetics with the spin state of active sites, and suggests a nexus between photocatalysis and spin theory.  相似文献   
84.
Water wave energy is a promising renewable energy source that may alleviate the rising concerns over current resource depletion, but it is rarely exploited due to the lack of efficient energy harvesting technologies. In this work, a hybrid system with a triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG) based on an optimized inner topological structure is reported to effectively harvest water wave energy. The TENG with etched polytetrafluoroethylene films and Cu electrodes utilizing the contact‐freestanding mode is designed into a cubic structure, in which the EMG is well hybridized. An integration of TENG and EMG achieves mutual compensation of their own merits, enabling the hybrid system to deliver satisfactory output over a broad range of operation frequency. The output performance of TENG with varied inner topological structures is experimentally and theoretically compared, and a concept is proposed to further clarify the energy conversion efficiency, which should be considered in designing energy harvesting devices. The influences of oscillation frequency, amplitude, and dielectric materials on the output performance of the hybrid system are comprehensively studied on different platforms. Furthermore, the optimum operation frequency ranges for TENG and EMG are concluded. The proposed hybrid nanogenerator renders an effective approach toward large‐scale blue energy harvesting over a broad frequency range.  相似文献   
85.
PI3K/Akt信号通路是由酶联受体介导的信号转导通路,该通路不仅参与多种生长因子、细胞因子和细胞外基质等的信号转导,同时还参与细胞增殖、分化、凋亡和葡萄糖转运等多种细胞功能的调节,特别是在细胞凋亡、细胞存活以及调控细胞糖代谢等方面具有重要作用。本研究综述了PI3K-Akt信号通路的结构组成、通路活化、通信过程、调控机制及其生物学功能等方面的研究进展,为进一步研究PI3K/Akt信号通路的生物学调控作用机制提供启示。  相似文献   
86.
利用酵母双杂交系统,以黄瓜花叶病毒(Cucumber mosaic virus,CMV)的外壳蛋白(coat protein,CP)为诱饵,从番茄叶片c DNA文库中筛选与其互作的蛋白。结果显示,诱饵载体pBT3-SUC-CMV-CP均能在酵母细胞中正确表达,无自激活活性而且对酵母无毒性;通过对酵母双杂交文库的筛选和回转验证,共获得了98个阳性克隆,分别编码67个可能与CMV-CP相互作用的蛋白,分别参与植物防御反应、光合作用、物质转运、信号转导、能量代谢、氨基酸代谢、细胞壁的形态建成、植物的激素代谢等。本研究结果表明,CMV CP可同时调控寄主的多个代谢过程,在CMV的致病过程中有多重功能。  相似文献   
87.
Li  Zhihui  Zhu  Peng  Huang  Hui  Pan  Ying  Han  Peng  Cui  Huanhuan  Kang  Zhijuan  Xun  Mai  Zhang  Yi  Liu  Saijun  Wang  Jian  Wu  Jing 《中国科学:生命科学英文版》2019,62(12):1572-1579
Alport syndrome(AS) is a hereditary progressive nephropathy characterized by hematuria, ultrastructural lesions of the glomerular basement membrane, ocular lesions and sensorineural hearing loss. Germline mutations of COL4 A5 are associated with X-linked AS with an extreme phenotypic heterogeneity. Here, we investigated a Chinese family with Alport syndrome. The proband was a 9-year-old boy with hematuria and proteinuria. Based on the test results of renal biopsy and immunofluorescence,the proband was initially diagnosed as Ig A nephropathy and the treatment was recommended accordingly. Meanwhile, we found that the treatment outcome was poor. Therefore, for proper clinical diagnosis and appropriate treatment, targeted exome-based next-generation sequencing has been undertaken. We identified a novel hemizygous single nucleotide deletion c.1902 del A in COL4 A5 gene. Segregation analysis identified that this novel mutation is co-segregated among the affected family members but absent in unaffected family members. The clinical diagnosis of the proband was revised as AS accompanied by Ig A nephropathy,which has been rarely reported. Our findings demonstrated the significance of the application of Genetic screening, expanded the mutation spectrum of COL4 A5 associated AS patients with atypical renal phenotypes and provided a good lesson to be learned from our detour during the diagnosis.  相似文献   
88.
Chronic obstructive pulmonary disease(COPD), lung cancer(LC) and tuberculosis(TB) are common chronic lung diseases that generate a large disease burden and significant health care resource use in China. The aim of this study was to quantify spatial patterns and effects of air pollution and meteorological factors on hospitalization of COPD, LC and TB in Beijing. Daily counts of hospitalization for 2010 were obtained from the Beijing Urban Employees Basic Medical Insurance(UEBMI) system.Bayesian hierarchical Poisson regression models were applied to identify spatial patterns of hospitalization for COPD, LC and TB at the district level and explore associations with inhalable particulate matter(aerodynamic diameter 10 μm, PM_(10)), sulfur dioxide(SO_2), nitrogen dioxide(NO_2), mean temperature and relative humidity. There were 18,882, 14,295 and 2,940 counts of hospitalizations for COPD, LC and TB respectively, in Beijing in 2010. Clusters of high relative risk were in different locations for the three diseases. The effect of relative humidity on COPD hospitalization was most significant with a relative risk(RR) of 1.070(95%CI: 1.054, 1.086) per one percent increase. For lung cancer hospitalization, exposure to ambient SO_2 was associated with a RR of 1.034(95%CI: 1.011, 1.058) per μg m~(–3) increase. For tuberculosis, the effect of mean temperature was significant with a RR of 1.107(95%CI: 1.038, 1.180) per °C increase. Risk factors and spatial patterns were different for hospitalization of non-infectious and infectious chronic lung disease in Beijing. Even over a short time period(one year), associations were apparent with air pollution and meteorological factors.  相似文献   
89.
Liu  Lei  Zeng  Dong  Yang  Mingyue  Wen  Bin  Lai  Jing  Zhou  Yi  Sun  Hao  Xiong  Lvcheng  Wang  Jie  Lin  Yicen  Pan  Kangcheng  Jing  Bo  Wang  Ping  Ni  Xueqin 《Probiotics and antimicrobial proteins》2019,11(4):1278-1292

Probiotics could promote animal growth and enhance immune function. This study investigated the effects of Clostridium butyricum (CB) on the growth performance, intestinal immune, and gut microbiota of weaning rex rabbits. A total of 60 healthy female rabbits (5-month-old) were divided equally into four groups and mated on the same day: control group (CTRL, fed with basal feed), low-dose group (LDG, fed with basal feed + 1.0 × 103 CFU/g CB), middle-dose group (MDG, fed with basal feed + 1.0 × 104 CFU/g CB), and high-dose group (HDG, fed with basal feed + 1.0 × 105 CFU/g CB). Then, 30 weaning rex rabbits (35-day-old) were collected from each group for this experiment, and they were offered the same feeds as their mother. The results demonstrated that high-dose CB treatment significantly increased average daily weight gain of weaning rex rabbits. Further studies suggested that CB enhanced small intestinal digestive enzyme activity and improved mucosal morphology and antioxidant status. Supplemented with CB, small intestinal barrier function was maintained with the upregulation of mRNA levels of ZO-1, claudin, and occludin as well as the increase of sIgA production. Moreover, the relative expressions of MyD88, TLR2, and TLR4 were elevated in HDG; simultaneously, pro-inflammatory cytokines including IL-6, INF-γ, and TNF-α were decreased after CB administration. In addition, CB showed beneficial effects in improving weaning rex rabbit intestinal microflora via increasing the abundance of beneficial bacteria. Therefore, our results indicated CB can promote rex rabbit growth, which is likely to the enhancement of immune function and the improvement of intestinal microbiota.

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90.
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