Silencing of Long Non-Coding RNA MALAT1 Promotes Apoptosis of Glioma Cells

Jianping Xiang,Shifeng Guo,Shuling Jiang,Yuelong Xu,Jiwei Li,Li Li,Jinyu Xiang 대한의학회 2016 Journal of Korean medical science Vol.31 No.5

The metastasis-associated lung adenocarcinoma transcription 1 (MALAT1) is a highly conserved long non-coding RNA (lncRNA) gene. However, little is known about the pathological role of lncRNA MALAT1 in glioma. In the present study, we explored the expression level of lncRNA MALAT1 in primary glioma tissues as well as in U87 and U251 glioma cell lines. Using qRT-PCR, we found that the expression of lncRNA MALAT1 was significantly increased in glioma tissues compared with that of paracancerous tissues. Meanwhile, the expression of MALAT1 was highly expressed in U98 and U251 cells. In order to explore the function of MALAT1, the expression of MALAT1 was greatly reduced in U87 and U251 cells transfected with siRNA specifically targeting MALAT1. Consequently, cell viability of U87 and U251 cells were drastically decreased after the knockdown of MALAT1. Concomitantly, the apoptosis rate of the two cell lines was dramatically increased. Furthermore, the expression levels of some tumor markers were reduced after the knockdown of MALAT1, such as CCND1 and MYC. In summary, the current study indicated a promoting role of MALAT1 in the development of glioma cell.

Hounsfield Units as an Independent Predictor of Failed Percutaneous Drainage of Spinal Tuberculosis Paraspinal Abscess Under Computed Tomography Guidance

Yu Xiang,Jinyue He,Ruonan Bai,Huorong Gou,Fei Luo,Xuequan Huang,Zehua Zhang 대한척추신경외과학회 2023 Neurospine Vol.20 No.4

Objective: To investigate the value of Hounsfield units (HUs) as an independent predictor of failed percutaneous drainage of spinal tuberculosis paraspinal abscess under computed tomography (CT) guidance. Methods: A retrospective analysis was conducted on 61 patients who underwent CT-guided percutaneous drainage for spinal tuberculosis paraspinal abscess between October 2017 and October 2020. Preoperative CT scans were used to measure the HUs of the abscess. Patients were categorized into successful drainage (n = 49) and failed drainage (n = 12) groups. Statistical analysis involved independent sample t-tests and chi-square tests to compare between the 2 groups. Binary logistic regression was performed to identify independent predictive factors for drainage failure. Receiver operating characteristic (ROC) curves were employed to ascertain risk factor thresholds and diagnostic performance. Results: Among the patients, 49 experienced successful drainage while 12 faced drainage failure. The mean HUs of abscesses in the failed drainage group were significantly higher than those in the successful drainage group (p < 0.001). ROC analysis revealed an area under the curve of 0.897 (95% confidence interval, 0.808–0.986) for predicting drainage failure based on HUs. The optimal HU cutoff value for predicting drainage failure was 22.3, with a sensitivity of 91.7% and specificity of 69.4%. Conclusion: HUs are an independent predictor of failed percutaneous drainage of spinal tuberculosis paraspinal abscess under CT guidance. The HU value of 22.3 can be used as an initial screening threshold for predicting the success or failure of drainage.

Active current-limiting control to handle DC line fault of overhead DC grid

MENG Zhou,WANG Xiang,WENPING Zuo,WEIXING Lin,JINYU Wen,RUIZHANG Yang,BINYE Ni,XIAOJUN Lu 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

To handle with the DC line faults in a DC grid, this paper proposed an active current-limiting controller for hybrid MMC. With this active current-limiting control strategy, the requirement of interruption current of DCCB will be significantly decreased, and the investment of DC grid will be reduced obviously. Firstly, the control architecture of active current-limiting controller is disclosed. To avoid the overvoltage of submodule capacitors during DC fault, a dynamic limiter for the reference value of the DC current controller is proposed. To decrease the peak of fault current, the feedforward controller of DC voltage is put forward. The decoupling controllability of the AC/DC voltage of hybrid MMC is disclosed. The currentlimiting mechanism of the active current-limiting controller is analysis. Then, the validity of the active current-limiting control strategy is verified by RTDS.

The transcription factor PjERF1 enhances the biosynthesis of triterpenoid saponins in Panax japonicus

Chen Qin,Yu Yilin,Zhang Xiang,Zhao Ren,Zhang Jinyu,Liu Diqiu,Cui Xiuming,Ge Feng 한국식물생명공학회 2021 Plant biotechnology reports Vol.15 No.5

The ERF-type transcription factors (TFs) play vital roles in plant secondary metabolism. ERF TFs simultaneously regulate the expression levels of key enzyme genes involved in the biosynthesis of secondary metabolites due to its “multi-point control” function. In this study, one gene of ERF TFs from Panax japonicus (PjERF1) was cloned. The open reading frame of PjERF1 was 801 bp and encoded 266 amino acids. Phylogenetic analysis showed that PjERF1 belonged to ERF subfamily with a typical conserved domain. Subcellular localization found that PjERF1 protein might be located in eukaryotic cell nucleus. Yeast one-hybrid assay demonstrated that PjERF1 could bind to the promoters of PjβAS, PjCAS, and PjSE specifically and regulate the expression levels of such key enzyme genes involved in the triterpene saponins biosynthesis. Therefore, in the PjERF1 overexpression cell lines, the expression levels of some key enzyme genes involved in the triterpenoid saponins biosynthesis were significantly increased compared with those in non-transgenic cell line. As a result of it, the biosynthesis of chikusetsusaponin IV and IVa, and other ginsenosides (Rd, Rb1, Re, and R0) were also promoted in the PjERF1 over- expression cell lines. This study indicated that PjERF1 could regulate the biosynthesis of saponins in P. japonicus through controlling the expression levels of key enzyme genes related to the biosynthesis of triterpenoid saponins.

A Three-Terminal Hybrid HVDC System Based on LCC and Hybrid MMC with DC Fault Clearance Capability

Wei Han,Ruizhang Yang,Wang Xiang,Chao Liu,Weidong Ma,Jinyu Wen 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

In this paper, a three-terminal hybrid HVDC system based on LCC and hybrid MMC is proposed, which has the ability of DC fault clearance. The system combines the merits of hybrid HVDC system and multi-terminal HVDC system, which is able to deliver bulk renewable power to multiple receiving power grids at a relatively lower cost. By utilizing hybrid MMC as the inverters, the system has the capability to ride through DC faults. The topology and the operating characteristics of the system are introduced in detail. The design of the hybrid MMC is analyzed. The control strategy and the DC fault ride through strategy are proposed. Finally, the model of three-terminal HVDC system is built in PSCAD / EMTDC. The simulation verifies the effectiveness of the control strategy and the DC fault ride through strategy. The results indicate that this kind of HVDC system has a good application prospect in bulk power transmission to the multiple remote receiving regional power grids and the DC fault ride through ability proposed for the system operates well.

A Day-Ahead Optimization Method of Source–Load Coordination for Power System Using Demand Response and Stackelberg Game

Yuan Xin,Tang Hao,Liu Xin,Zhou Xiang,Guan Jinyu 대한전기학회 2024 Journal of Electrical Engineering & Technology Vol.19 No.3

The continuous expansion of renewable energy sources and their ongoing integration into existing power networks, alongside the emergence of new types of loads, has led to signifcant new challenges emerging for power grid source–load coordination scheduling in recent years. To fully harness the demand response (DR) potential of the load side of such systems, this paper proposes an optimal scheduling method based on DR and the Stackelberg game. A Stackelberg game model is established to formulate day-ahead source–load coordinated scheduling problem, taking account of the stochastic dynamic characteristics of the load response process and user electricity consumption satisfaction with electricity consumption. The model is essentially a strongly nonlinear optimization problem, however; thus, to avoid several of the limitations seen in traditional optimization methods, a data-model fusion-driven method is proposed, with electricity prices formulated by the data-driven method used as input for a model-driven method whose output is then used in turn to guide a data-driven formulation of electricity prices. Case studies on IEEE test systems are used to verify the feasibility and accuracy of the proposed method.