Clinical and Prognostic Significance of O⁶-Methylguanine-DNA Methyltransferase Promoter Methylation in Patients with Melanoma: A Systematic Meta-Analysis

( Fang Qi Zhiqi Yin ),( Guangping Wang ),( Sanwu Zeng ) 대한피부과학회 2018 Annals of Dermatology Vol.30 No.2

Tumor suppressor gene O⁶-methylguanine-DNA methyltransferase (MGMT) promoter methylation has been reported in melanoma. However, the clinical and prognostic significance of MGMT promoter methylation in patients with melanoma remained to be determined. A systematic search was performed to identify eligible papers published. The overall odds ratios (ORs) or hazard ratios and their 95% confidence intervals were calculated. Final 12 eligible publications involving Caucasian population were performed in this study, including 1,071 metastatic melanoma patients, 154 primary melanoma patients, and 211 normal controls. MGMT promoter methylation was significantly higher in primary or metastatic melanoma than in normal controls (p<0.05). No difference of MGMT promoter methylation was found in primary and metastatic melanoma (p=0.432). When metastatic melanoma was compared to normal controls, subgroup analysis showed the correlation between MGMT promoter methylation and different sample materials (tissue: OR=7.01, p<0.001 and blood: OR=12.04, p=0.005). MGMT promoter methylation was not associated with response to drug therapy and the prognosis in overall survival and progression-free survival for multivariate analysis. Our results show that MGMT promoter methylation may be correlated with the increased risk of primary or metastatic melanoma. Based on blood samples, MGMT promoter methylation may become a noninvasive biomarker for the detection of metastatic melanoma. Further additional clinical studies are necessary. (Ann Dermatol 30(2) 129∼135, 2018)

Prediction of Undisturbed Clay Rebound Index Based on Soil Microstructure Parameters and PSO-SVM Model

Jiaqi Dong,Boxin Wang,Xuexin Yan,Xinchuan Xu,Guangping Xiao,Qingbo Yu,Meng Yao,Qing Wang 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.5

The rebound index Cr is an important design parameter in engineering construction, and its determination is cumbersome and susceptible to errors. Explaining the macroscopic rebound characteristic parameter Cr from the perspective of microscopic mechanism is an important research area that is addressed in this study. In this paper, the different soil parameters, including the Cr parameter and the physical parameters (void ratio e, liquid limit water contentwL, and plasticity index Ip), have been determined through experiments for the undisturbed clay of Chongming East Shoal (CES), Shanghai. Further, scanning electron microscopy (SEM) imaging was used to analyze the microstructural features. Through SEM, the grey correlation degree, the average abundance of structural units ACp and the average equivalent diameter of pores ADv were determined as the soil microstructure parameters with the most significant correlation with Cr. The predictive analysis model of Cr was then carried out combined with the PSO-SVM algorithm. In order to evaluate the influence of microscopic parameters of soil on the prediction accuracy, four sets of input parameter combinations were used. The results indicate the high prediction accuracy of the developed model. Sensitivity analysis was also carried out, which showed that the sensitivity of Cr to ACp and ADv was significantly lower than e; however, the difference from wL and Ip was small, indicating that it is imperative to consider microscopic parameters while predicting Cr. This study, thus, provides a basis and method for predicting the rebound index of soil from the microstructure perspective.

Effect of glass cooling rate on the crystallization behavior and structure of Al2O3-SiO2-Na2O-CaF2 oxyfluoride glass-ceramics

Mengxuan Li,Jinxin Zou,Guangping Guo,Jianxiang Liu,Guicheng Wang 한양대학교 세라믹연구소 2021 Journal of Ceramic Processing Research Vol.22 No.5

The glass cooling rate during molding process has significant effect on the crystallization behavior and structural uniformityof Al2O3-SiO2-Na2O-CaF2 oxyfluoride glass-ceramics. Abaqus Finite Element Analysis indicated that at room temperaturecooling environment, the cooling rate of 8mm thick glass was notably lower than that of 3 mm thick glass. The interiortemperature of 8 mm thick precursor glass was still above 710 oC even after the sample was cooled for 15 s, which caused theformation of “crystal stones” in precursor glass. The microstructure of oxyfluoride glass and glass-ceramics with differentthickness was analyzed by using DTA, XRD, IR and SEM. Since the 8 mm thick glass was cooled slowly, the initial crystalnucleation generated in the interior of glass, mixed crystal phases were formed in the interior after heat treatment, while singleCaF2 crystal phase formed on the surface. On the contrary, there was only uniform CaF2 crystal phase generating in the 3mm thick precursor glass after heat treatment, as a result of high cooling rate during molding process. Besides, the mechanismand ways to optimize the structure uniformity of glass ceramics were also be discussed.

Experimental and theoretical analysis of element mercury adsorption on Fe3O4/Ag composites

Lu Dong,Jiangkun Xie,Guangping Fan,Yaji Huang,Jun Zhou,Qingke Sun,LiangWang,Zhengwen Guan,Di Jiang,Ye Wang 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.11

A novel magnetic nano-sorbent Fe3O4/Ag was synthesized and applied to capture the elemental mercury from the simulated flue gas. The morphology, components and crystal phase of the sorbents were characterized by transmission electron microscope (TEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD), respectively. The mercury removal performance of the sorbents was investigated through the fixed-bed tests. The results indicated that silver was successfully loaded on the surface of Fe3O4 particles, which could significantly enhance the Hg0 removal performance of the sorbents. Flue gas components, including CO2, SO2, and NO, have little impact on the Hg0 removal performance of Fe3O4/Ag sorbents, while O2 has a slightly positive effect. The Hg0 removal efficiency decreased with the increasing of temperature, Hg0 inlet concentration and gas hourly space velocity. Only one broad mercury desorption peak at approximately 210 oC could be observed during the temperature-programmed desorption (TPD) process, which indicated that mercury species existing on the surface of Fe3O4/Ag sorbents might be elemental mercury instead of oxidized mercury. Furthermore, the reusability tests showed that the Fe3O4/Ag sorbents could be efficiently regenerated and reused. Finally, the theoretical analysis based on the DFT method showed that a weak chemisorption of Hg0 on Fe3O4 sorbents changed to a strong chemisorption when silver was loaded. The results of theoretical analysis conformed to the experiments results well.

Infection of Oligochaetes, Limnodrilus hoffmeisteri (Annelida: Oligochaeta), in the Nasal Cavity of a Chinese Man

Hongbin Liu,Zhenming Zhang,Guangping Huang,Xiaolong Gu,Chunmiao Wang,Yan Wang,Zhimin Lu 대한기생충학열대의학회 2017 The Korean Journal of Parasitology Vol.55 No.1

Study on tool wear for efficient grooving blisk with disc milling cutter

Qingsi Cheng,Song Wang,Hongmin Xin,Jian Zhang,Changfeng Yao,Minchao Cui,Guangping Li 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.10

Tool wear has an important influence on machining quality, cost, cutting force and heat. Grooving blisk with disc milling cutter is 3-4 times more efficient than plunge milling and side milling, but the tool wear is serious because of the large milling force and high milling temperature during the machining process. In the study, the damage and wear morphology of the tool was observed by focused ion/double beam system; the wear mechanism was studied by energy spectrum analysis; the tool life curve was drawn by the increase of flank wear. The experimental results show that the main wear and damage morphologies of disc milling cutter are chip sticking to the tool, chip accumulation, edge collapse, peeling, crack, plastic deformation and boundary wear; the main wear mechanism are abrasive wear, adhesive wear, oxidation wear and diffusion wear; the wear rate of the left blade is the fastest, followed by the right blade, and the wear rate of the middle blade is the slowest. These results can provide guidance for iimproving tool life, optimizing tool and mproving machining processes.