Epigenetic inactivation of ACAT1 promotes epithelial-mesenchymal transition of clear cell renal cell carcinoma

Han Peipei,Wu Shu,Li Limei,Li Danping,Zhao Jun,Zhang Haishan,Wang Yifang,Zhong Xuemin,Zhang Zhe,Li Ping,Matskova Liudmila,Zhou Xiaoying 한국유전학회 2022 Genes & Genomics Vol.44 No.4

Background: Acetyl-CoA acyltransferase 1 (ACAT1) is a key enzyme catalyzing the production of mitochondrial ketone bodies. We have shown that ACAT1 is down-regulated in kidney renal clear cell carcinoma (KIRC) previously. Objective: To investigate the reasons for downregulation of ACAT1 in KIRC and explore the underlying mechanisms involved in metastatic inhibition regulated by ACAT1. Methods: The Gene Expression Omnibus (GEO) database was queried for meta-analysis of ACAT1 mRNA expression in KIRC. The UALCAN website was used to compare the methylation levels of the ACAT1 promoter region in KIRC and normal tissues. RT-qPCR was used to quantitate ACAT1 transcription levels. The GCBI and Tarbase V.8 databases were used to predict miRNAs that may target the mRNA of ACAT1. The correlation between mRNA expression of ACAT1, MMP7 (matrix metallopeptidase 7), CDH1 (E-cadherin), EpCAM (epithelial cell adhesion molecule), and VIM (vimentin) was analyzed. Extracellular MMP7 protein was quantitated using an ELISA assay. Results: The methylation level of the ACAT1 promoter region in KIRC was significantly higher than that in the normal kidney tissues. The ACAT1 mRNA expression in the KIRC cell lines was restored after treatment with 5-aza-dC (p < 0.05). MiR-21-5p is a conserved microRNA targeting ACAT1. It is expressed at a significantly higher level in KIRC than in normal tissues (p < 0.001). MiR-21-5p miRNA expression negatively correlates with ACAT1 mRNA expression. The expression of miR-21-5p is higher at the T3-T4 stages and in the histologic grades G3-G4. Patients with high miR-21-5p expression tended to have lower overall survival, suggesting that miR-21-5p could serve as a potentially valuable diagnostic biomarker for KIRC (AUC = 0.957; p < 0.001). A mimetic of miR-21-5p inhibited the expression of ACAT1 mRNA and protein. In addition, ACAT1 mRNA expression positively correlates with CDH1 and EpCAM but is negatively correlated with VIM. Overexpression of ACAT1 suppresses the secretion of MMP7 in KIRC cells. Conclusion: Expression of ACAT1 in KIRC is controlled at two levels, firstly by the hypermethylation of the ACAT1 promoter region and secondly by overexpression of miR-21-5p. Downregulation of ACAT1 expression correlates with epithelial-mesenchymal transition (EMT).

Preparation of Tunable Emissive Poly(ethylene oxide) Nanofibers by Doping with TPP and DCM

Lianji Zhang,이연식,Dongri Zhang,Sumei Zhan,Peipei Yang,Guixia Yang,Zonghao Huang 한국고분자학회 2012 Macromolecular Research Vol.20 No.2

Poly(ethylene oxide) (PEO) nanofibers that were doubly-doped with a donor, 1,3,5-triphenyl-2-pyrzoline (TPP), and an acceptor, 4-(dicyanomethylene)-2-methyl-6-(p-dimethyl-aminostyryl)-4H-pyran (DCM), were prepared by electrospinning to be 200-300 nm in diameter. Fluorescence from DCM was caused by non-radiative Forster-type fluorescence resonance energy transfer from photo-excited TPP to DCM. The color of the fluorescence from the PEO-TPP/DCM nanofibers was controllable through variation of the TPP:DCM molar ratio and ranged from blue to orange to white.

Impact of electrolyte additives (alkali metal salts) on the capacitive behavior of NiO-based capacitors

Yong Zhang,Lizhen Wang,Aiqin Zhang,Yanhua Song,Xiaofeng Li,Xingbing Wu,Peipei Du,Lv Yan 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.2

To improve the specific capacitance and energy density of electrochemical capacitor, nanostructured NiO was prepared by high temperature solid-state method as electrode material. The crystal structure and morphology of as-parepared NiO samples were investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Cyclic voltammetry (CV) measurement was applied to investigate the specific capacitance of the NiO electrode. Furthermore,a novel mixed electrolyte consisting of NaOH, KOH, LiOH and Li_2CO_3 was prepared for the NiO capacitor,and the component and concentration of the four different electrolytes was examined by orthogonal test. The results showed that the NiO sample has cubic structure with nano-size particles, and the optimal composition of the electrolyte was: NaOH 2 mol L^(−1), KOH 3 mol L^(−1), LiOH 0.05 mol L^(−1), and Li_2CO_3 0.05 mol L^−1. At a scan rate of 10 mV s^(−1), the fabricated capacitor exhibits excellent electrochemical capacitive performance, while the specific capacitance and the energy density were 239 F g^(−1) and 85 Wh kg^(−1), which was higher than one-component electrolyte.

Kinetics and Modeling for Extraction of Chrysin from Oroxylum indicum Seeds

Li Zhou,Ting Jing,Peipei Zhang,Liqin Zhang,Shaona Cai,Tingting Liu,Huihui Fan,Guangde Yang,Rong Lin,Jiye Zhang 한국식품과학회 2015 Food Science and Biotechnology Vol.24 No.6

Research on extraction of chrysin is crucial for theoretical purposes and for food industrial bioprocesses. Optimization and kinetics of chrysin extraction from seeds of Oroxylum indicum (L.) Vent. were analyzed using agitated solid-liquid extractions with ethanol and water mixtures. The influence of extraction process parameters was investigated. Optimized conditions for chrysin extraction were a 0.2 mole fraction of ethanol as an extraction solvent, a temperature of 318 K, an agitation speed 1,400 rpm, and a solid to solvent ratio of 1:30. The extraction kinetic behavior of chrysin followed first order kinetics. The kinetic expression developed by Spiro and Siddique was used and the model was in agreement with experimental results. The diffusion coefficient ranged from 1.38×10−11 to 19.43×10−11 m2·s−1 and the activation energy for extraction kinetics was 21.85 kJ·mol−1.

Computing Minimal Curvature Variation in Curve Construction Using Computer Simulation Technique

Peipei Li,Caiming Zhang (사)한국CDE학회 2010 한국CAD/CAM학회 국제학술발표 논문집 Vol.2010 No.8

Aetiology and Progression of Construction Disputes towards a Predictive Model

Peipei Wang,Lihan Zhang,Kun Wang,Peter Fenn 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.4

Construction projects are at risk of dispute. Dispute prevention is thus expected to avoid that cost. This paper aims to establish a model predicting the occurrence of disputes and identifying strategies regarding resource allocation in dispute avoidance. Factors in the model were identified by a literature review and conceptualised into aetiology and progression of dispute formation based on an analogy with epidemiological investigations. The model structure was established upon this analogy, validated against Bradford Hill criteria, and then quantified by conducting a Bayesian network analysis with samples returned from a questionnaire survey. The model shows high accuracy rates with both complete and incomplete input data. Finally, a sensitivity analysis was conducted to simulate the results of potential management measures available to be taken. This predictive model not only serves the prediction function but also traces back to factors causing disputes, and hence can be used to assist decision making before and during a construction process. At the centre of the model sits the causal mechanism investigation, but the existing methods only shed lights on correlational research without causal consideration. This paper devised an epidemiological investigation which covers from causal proposition to causal examination and contributes greatly to model establishment.

Dose-Response Relationship between Alanine Aminotransferase Levels within the Reference Interval and Metabolic Syndrome in Chinese Adults

Peipei Wu,Shumei Wang,Qicai Chen,Lili Chen,Pengpeng Zhang,Juan Xiao,Xiaoxiao Chen,Meng Liu 연세대학교의과대학 2017 Yonsei medical journal Vol.58 No.1

Purpose: Elevation in serum alanine aminotransferase (ALT) levels is a biomarker for metabolic syndrome (MS); however, the relationshiphas not been fully investigated within the reference interval of ALT levels. Our objective was to explore the relationship between serum ALT levels within the reference interval and MS in Chinese adults. Materials and Methods: This cross-sectional study included 16028 adults, who attended routine health check-ups at Shengli OilfieldCentral Hospital from January 2006 to March 2012. The reference interval of serum ALT level was defined as less than 40 U/L. Logistic regression models and restricted cubic spline were used to evaluate the association of ALT with MS. Results: The prevalence of MS in the total population was 13.7% (6.4% for females and 18.4% for males). Multiple logistic regressionshowed that ALT levels were positively associated with MS after adjustment for potential confounding factors. The odds ratio of MS in the top quartile was 4.830 [95% confidence interval (CI): 2.980–7.829] in females and 3.168 (95% CI: 2.649–3.790) in males, compared with the ALT levels in the bottom quartile. The restricted cubic spline models revealed a positive non-linear dose-response relationship between ALT levels and the risk of MS in women (p for nonlinearity was 0.0327), but a positive linear dose-response relationship in men (p for nonlinearity was 0.0659). Conclusion: Serum ALT levels within the reference interval are positively associated with MS in a dose-response manner. ElevatedALT levels, even within the reference interval, may reflect early dysmetabolic changes.

An Investigation on Stress States of the Cataclastic Rock Specimen under Confined Compression Based on Modified Thick-walled Cylinder Model

Jin Zhang,Ronggui Deng,Zhibin Zhong,Peipei Wu,Shaoli Qi 대한토목학회 2023 KSCE Journal of Civil Engineering Vol.27 No.10

In high in-situ stress zones, cataclastic rocks have exerted a significant influence on the stability of engineering structures. However, the mechanical properties of cataclastic rocks can not be accurately studied due to difficulties in sampling and laboratory testing. In this paper, laterally confined compression tests for specimens that were obtained by the developed in-situ sampling devices were performed to investigate the stress states. A modified thick-walled cylinder model considering axial shear stress was introduced. The interaction mechanics model for a compressed sample and an equivalent single-layer cylinder was established. Based on the principle of elasticity, the laterally confined stress, the axial shear stress, and the axial stress of the sample were derived and obtained. Moreover, the effects of mechanical and geometric parameters of the equivalent cylinder on the force condition of the specimen were analyzed. The results show that the confined stress is positively correlated with the equivalent elastic modulus and the geometric factor. Therefore, the confined stress can be strengthened by increasing the elastic modulus, alternatively, increasing the outer diameter and decreasing the inner diameter. However, the axial stress is little affected by the equivalent elastic modulus and the geometric factor and is not affected by the equivalent Poisson's ratio. As the distance from the center height increases, the axial stress decreases linearly and the difference in axial stress becomes larger considering axial shear stress and ignoring axial shear stress.

Long Non-Coding RNA RMRP Contributes to Sepsis-Induced Acute Kidney Injury

Xia Zhang,Zhongwei Huang,Yan Wang,Ting Wang,Jingjing Li,Peipei Xi 연세대학교의과대학 2021 Yonsei medical journal Vol.62 No.3

Purpose: This study aimed to explore the role of the long non-coding RNA (lncRNA) RNA component of mitochondrial RNAase P (RMRP) in sepsis-induced acute kidney injury (AKI). Materials and Methods: Venous blood was collected from septic patients and healthy people. C57BL/6 mice who underwent cecal ligation and puncture (CLP) were used as in vivo models of septic AKI. Lipopolysaccharide (LPS)-induced HK-2 cells were employed as in vitro models of AKI. Flow cytometry analysis was conducted to detect cell apoptosis. Enzyme-linked immunosorbent assay and Western blot assays were used to detect levels of pro-inflammatory cytokines. Results: RMRP was upregulated in sera from patients with AKI and in LPS-induced cells. Knockdown of RMRP inhibited cell apoptosis and reduced production of inflammatory factors in LPS-induced cells, as well as alleviated AKI in CLP mice. RMRP facilitated inflammation by activating NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome. We found that microRNA 206 (miR-206) binds with and is negatively regulated by RMRP: miR-206 directly targets the 3’ untranslated region of DEAD-box helicase 5 (DDX5) and negatively regulates DDX5 expression. By binding with miR-206, RMRP upregulated DDX5 expression. Rescue assays revealed that overexpression of DDX5 counteracted the effect of RMRP inhibition on cell apoptosis and inflammatory response in LPS-induced cells. Conclusion: The lncRNA RMRP contributes to sepsis-induced AKI through upregulation of DDX5 in a miR-206 dependent manner and through activation of NLRP3 inflammasome. This novel discovery may provide a potential strategy for treating AKI.

Dynamic Trust Model Based on Extended Subjective Logic

( Tian Junfeng ),( Zhang Jiayao ),( Zhang Peipei ),( Andma Xiaoxue ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.8

In Jøsang’s trust model, trust evaluation is obtained through operators, but there are problems with the mutuality and asymmetry of trust and the impact of event weight on trust evaluation. Trust evaluation is updated dynamically and continuously with time and the process of interactions, but it has not been reflected in Jøsang’s model. Therefore, final trust evaluation is not accurate, and malicious fraud cannot be prevented effectively. This causes the success rate of interaction to be low. To solve these problems, a new dynamic trust model is proposed based on extended subjective logic (DTM-ESL). In DTM-ESL, the event weight and the mutuality of trust are fully considered, the original one-way trust relationship is extended to a two-way trust relationship, discounting and consensus operators are improved, and trust renewal is designed based on event weight. The viability and effectiveness of this new model are verified by simulation experiments.