[해외기술정보] 21세기 중국의 유체기계 기술과 중국 유체기계 학회

Xue Shengxiong,Jia Xiaofeng,Shu Pingling 한국유체기계학회 2005 한국유체기계학회 논문집 Vol.8 No.2

MicroRNA-590-5p Regulates Proliferation and Invasion in Human Hepatocellular Carcinoma Cells by Targeting TGF-beta RII

Xiaofeng Jiang,De Chen,Guangyang Xiang,Yezeng Wang,Lei Zhang,Xuewei Yang,Liangqi Cao,Heping Peng,Ping Xue 한국분자세포생물학회 2012 Molecules and cells Vol.33 No.6

MicroRNAs (miRNAs) are regulatory small non-coding RNAs that can regulate gene expression by binding to gene elements, such as the gene promotor 5UTR, mainly in the 3UTR of mRNA. One miRNA targets many mRNAs, which can be regulated by many miRNAs, leading to a complex metabolic network. In our study, we found that the expression level of miR-590-5p is higher in the human hepatocellular carcinoma cell line HepG2 than in the normal hepatocellular cell line L02. Downregulation of miR-590-5p inhibited proliferation and invasion of hepatocellular carcinoma cells (HCCs). We also showed that expression of TGF-beta RII, which has been regarded as a regulator of tumor proliferation, invasion, and migration in hepatocellular carcinoma, is regulated by miRNA-590-5p. In addition, miR-590-5p downregulated the expression of TGF- beta RII by targeting the 3UTR of mRNA. We also found that downregulation of miR-590-5p was associated with an elevation of TGF-beta RII and inhibition of proliferation and invasion in HepG2 cells. Furthermore, overex-pression of miR-590-5p was associated with upregulation of TGF-beta RII and could promote proliferation and invasion in L02 cells. In conclusion, we determined that TGF-beta RII is a novel target of miRNA-590-5p. Thus, the role of TGF-beta RII in regulating proliferation and invasion of human HCCs is controlled by miR-590-5p. In other words, miR-590-5p promotes proliferation and invasion in human HCCs by directly targeting TGF-beta RII.

Sealing design optimization of nuclear pressure relief valves based on the polynomial chaos expansion surrogate model

Zong Chaoyong,Shi Maolin,Li Qingye,Xue Tianhang,Song Xueguan,Li Xiaofeng,Chen Dianjing 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.4

Pressure relief valve (PRV) is one of the important control valves used in nuclear power plants, and its sealing performance is crucial to ensure the safety and function of the entire pressure system. For the sealing performance improving purpose, an explicit function that accounts for all design parameters and can accurately describe the relationship between the multi-design parameters and the seal performance is essential, which is also the challenge of the valve seal design and/or optimization work. On this basis, a surrogate model-based design optimization is carried out in this paper. To obtain the basic data required by the surrogate model, both the Finite Element Model (FEM) and the Computational Fluid Dynamics (CFD) based numerical models were successively established, and thereby both the contact stresses of valve static sealing and dynamic impact (between valve disk and nozzle) could be predicted. With these basic data, the polynomial chaos expansion (PCE) surrogate model which can not only be used for inputs-outputs relationship construction, but also produce the sensitivity of different design parameters were developed. Based on the PCE surrogate model, a new design scheme was obtained after optimization, in which the valve sealing stress is increased by 24.42% while keeping the maximum impact stress lower than 90% of the material allowable stress. The result confirms the ability and feasibility of the method proposed in this paper, and should also be suitable for performance design optimizations of control valves with similar structures.

Order–disorder structural tailoring and its effects on the chemical stability of (Gd, Nd)2(Zr, Ce)2O7 pyrochlore ceramic for nuclear waste forms

Wang Yan,Wang Jin,Zhang Xue,Li Nan,Wang Junxia,Liang Xiaofeng 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.7

Series of unequal quantity Nd/Ce co-doped ceramic nuclear waste forms, (Gd, Nd)2(Zr, Ce)2O7, were prepared to tailor its ordered pyrochlore or disordered fluorite structure. The phase transition, microtopography, and elemental composition of the ceramic samples were systematically investigated, especially the effect of order-disorder structure on the chemical stability. It was confirmed that unequal quantity of Nd/Ce could synchronously replace the Gd/Zr-sites of Gd2Zr2O7. And the phase transition of order-disorder structure could be successfully tailored by regulating the average cationic radius ratio of (Gd, Nd)2(Zr, Ce)2O7 series. The elements of Gd, Nd, Zr, and Ce are uniformly distributed in the ordered or disordered structures. The MCC-1 leaching results showed that (Gd, Nd)2(Zr, Ce)2O7 pyrochlore ceramic nuclear waste forms had excellent chemical stability, whose elements' normalized leaching rates were as low as 104 -107 g‧m2 ‧d1 after 7 days. In particular, the chemical stability of disordered structure was superior to that of ordered structure. It was proposed that the force constant and the closest packing were changed with the structure transformation resulting the chemical stability difference

Gemcitabine Inhibits the Progression of Pancreatic Cancer by Restraining the WTAP/MYC Chain in an m6A-Dependent Manner

Pei Cao,Weigang Zhang,Junyi Qiu,Zuxiong Tang,Xiaofeng Xue,Tingting Feng 대한암학회 2024 Cancer Research and Treatment Vol.56 No.1

Purpose Pancreatic cancer (PC) is a common malignant tumor of the digestive system, and its 5-year survival rate is only 4%. N6-methyladenosine (m6A) RNA methylation is the most common post-transcriptional modification and dynamically regulates cancer development, while its role in PC treatment remains unclear.Materials and Methods We treated PC cells with gemcitabine and quantified the overall m6A level with m6A methylation quantification. Real-time quantitative reverse transcription polymerase chain reaction and Western blot analyses were used to detect expression changes of m6A regulators. We verified the m6A modification on the target genes through m6A-immunoprecipitation (IP), and further <i>in vivo</i> experiments and immunofluorescence (IF) assays were applied to verify regulation of gemcitabine on Wilms’ tumor 1–associated protein (WTAP) and MYC.Results Gemcitabine inhibited the proliferation and migration of PC cells and reduced the overall level of m6A modification. Additionally, the expression of the “writer” WTAP was significantly downregulated after gemcitabine treatment. We knocked down WTAP in cells and found target gene MYC expression was significantly downregulated, m6A-IP also confirmed the m6A modification on MYC. Our experiments showed that m6A-MYC may be recognized by the “reader” IGF2BP1. <i>In vivo</i> experiments revealed gemcitabine inhibited the tumorigenic ability of PC cells. IF analysis also showed that gemcitabine inhibited the expression of WTAP and MYC, which displayed a significant trend of co-expression.Conclusion Our study confirmed that gemcitabine interferes with WTAP protein expression in PC, reduces m6A modification on MYC and RNA stability, thereby inhibiting the downstream pathway of MYC, and inhibits the progression of PC.

High-efficiency organic solar cells based on a small-molecule donor and a low-bandgap polymer acceptor with strong absorption

Yang, Yankang,Qiu, Beibei,Chen, Shanshan,Zhou, Qiuju,Peng, Ying,Zhang, Zhi-Guo,Yao, Jia,Luo, Zhenghui,Chen, Xiaofeng,Xue, Lingwei,Feng, Liuliu,Yang, Changduk,Li, Yongfang The Royal Society of Chemistry 2018 Journal of materials chemistry. A, Materials for e Vol.6 No.20

<P>Solution-processed organic solar cells (OSCs) have been attracting more and more attention for a series of well-known advantages, and power conversion efficiencies (PCEs) of over 11% have been reported. However, the highest PCE of the OSCs based on small molecule donor/polymer acceptor blends is only 4.82%, which was much lower than those of other types of OSCs due to weak absorption of the polymer acceptor and the unbalanced charge carrier mobility of the small molecule donor and the polymer acceptor. Here, we fabricated small molecule donor/polymer acceptor-based OSCs using the wide bandgap SM1 and DR3TBDTT as the small molecular donor and the low-bandgap n-type conjugated polymer PZ1 as the polymer acceptor. With the treatment of a solvent additive, which can promote the absorption intensity, enhance the carrier mobility and suppress the charge carrier recombination, the SM1-based devices and the DR3TBDTT-based devices show PCEs of 3.97% and 5.86%, respectively. It is worth mentioning that the PCE of 5.86% is the state-of-the-art efficiency for OSCs based on the small molecular donor/polymer acceptor system.</P>