Rapid characterization of ginsenosides in the roots and rhizomes of Panax ginseng by UPLC-DAD-QTOF-MS/MS and simultaneous determination of 19 ginsenosides by HPLC-ESI-MS

Wang, Hong-Ping,Zhang, You-Bo,Yang, Xiu-Wei,Zhao, Da-Qing,Wang, Ying-Ping The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.4

Background: Ginsenosides are the characteristic and principal components which manifest a variety of the biological and pharmacological activities of the roots and rhizomes of Panax ginseng (GRR). This study was carried out to qualitatively and quantitatively determine the ginsenosides in the cultivated and forest GRR. Methods: A rapid and sensitive ultra-high-performance liquid chromatography coupled with diode-array detector and quadrupole/time of flight tandem mass spectrometry (UPLC-DAD-QTOF-MS/MS) was applied to the qualitative analysis of ginsenosides and a 4000 QTRAP triple quadrupole tandem mass spectrometer (HPLC-ESI-MS) was applied to quantitative analysis of 19 ginsenosides. Results: In the qualitative analysis, all ingredients were separated in 10 min. A total of 131 ginsenosides were detected in cultivated and forest GRR. The method for the quantitative determination was validated for linearity, precision, and limits of detection and quantification. 19 representative ginsenosides were quantitated. The total content of all 19 ginsenosides in the forest GRR were much higher than those in the cultivated GRR, and were increased with the growing ages. Conclusion: This newly developed analysis method could be applied to the quality assessment of GRR as well as the distinction between cultivated and forest GRR.

Study on Nano-Metal Oxide and Carbon Nanotube Composites on Thermal Decomposition of Potassium Perchlorate

Ping-An Liu,Meng-Jun Wang,Lu Wang,Jun Wang,Ting Wang 대한화학회 2019 Bulletin of the Korean Chemical Society Vol.40 No.4

In this study, novel carbon nanotube (CNT) and transition-metal oxides (TMOs) nanoparticle catalysts were prepared and their effects on the thermal decomposition of potassium perchlorate (KP) were investigated. Nanocatalysts have been widely studied because of their excellent properties, such as the high surface energies of nanoparticles and their ease of agglomeration adversely affect their catalytic performances. Good dispersion is the key to good nanocatalytic activity. The composite catalysts were prepared by loading a nanocatalyst on CNTs; this improves nanoparticle dispersion, promotes electron transfer during the reaction, and increases the catalytic effect. Different types of CNT-based composite catalysts and their corresponding single nanocatalysts were each added to KP. The effects of the catalysts on the thermal decomposition of KP were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The activity of each catalyst was evaluated on the basis of the changes in the thermal decomposition peaks and the apparent decomposition heats. The results show that the activity of a composite catalyst in KP thermal decomposition is much higher than that of its corresponding single nanocatalyst.

Adverse effect of DEHP exposure on the serum insulin level of Balb/c mice

Jing Wang,Jinquan Li,Kashif Rafiq Zahid,Kun Wang,Yan Qian,Ping Ma,Shumao Ding,Xu Yang,Xianliang Wang,Xianliang Wang,Xu Yang 대한독성 유전단백체 학회 2016 Molecular & cellular toxicology Vol.12 No.1

Di(2-ethylhexyl) phthalate (DEHP) is a common indoor pollutant in the world, which may cause lots of harmful effects in human including diabetes according to epidemiological studies. To explore the underlying role of DEHP in diabetes-like symptoms, Balb/c mice were chose to be the experimental animals in this paper. They were separated as eight groups as follows: (1) saline+normal diet (vehicle control), (2) 10 mg/kg.day DEHP+normal diet, (3) 50 mg/kg.day DEHP+normal diet, (4) 250 mg/kg.day DEHP+normal diet, (5) streptozotocin (STZ)+high fat diet (diabetes model), (6) 10 mg/kg.day DEHP+ STZ+high fat diet, (7) 50 mg/kg.day DEHP+STZ +high fat diet, (8) 250 mg/kg.day DEHP+STZ+high fat diet. The biomarkers of this experiment include four groups: (1) general indicates: body weight and drinking water, (2) blood biomarkers: serum insulin and fasting glucose, (3) pathological examination: pancreas section and kidney section, and (4) biomarkers of oxidative stress: reactive oxygen species (ROS) and malondialdehyde (MDA) in liver cells. Our study results demonstrate that: (1) at our treatment levels DEHP cannot directly induce diabetes, but reduce serum insulin level in DEHP-exposed non-STZ-treated animals, (2) pathological examination finds that these is a dose-dependent damage in the pancreas in DEHP- exposed STZ-treated groups, and (3) the oxidative mechanism may be involved in this pathological process.

Complete ¹H-NMR and <SUP>13</SUP>C-NMR spectral assignment of five malonyl ginsenosides from the fresh flower buds of Panax ginseng

Yu-Shuai Wang,Yin-Ping Jin,Wei Gao,Sheng-Yuan Xiao,Yu-Wei Zhang,Pei-He Zheng,Jia Wang,Jun-Xia Liu,Cheng-He Sun,Ying-Ping Wang 고려인삼학회 2016 Journal of Ginseng Research Vol.40 No.3

Background: Ginsenosides are the major effective ingredients responsible for the pharmacological effects of ginseng. Malonyl ginsenosides are natural ginsenosides that contain a malonyl group attached to a glucose unit of the corresponding neutral ginsenosides. Methods: Medium-pressure liquid chromatography and semipreparative high-performance liquid chromatography were used to isolate purified compounds and their structures determined by extensive one-dimensional- and two-dimensional nuclear magnetic resonance (NMR) experiments. Results: A new saponin, namely malonyl-ginsenoside Re, was isolated from the fresh flower buds of Panax ginseng, along with malonyl-ginsenosides Rb1, Rb2, Rc, Rd. Some assignments for previously published ¹H- and <SUP>13</SUP>C-NMR spectra were found to be inaccurate. Conclusion: This study reports the complete NMR assignment of malonyl-ginsenoside Re, Rb₁, Rb₂, Rc, and Rd for the first time.

Prediction Models for Solitary Pulmonary Nodules Based on Curvelet Textural Features and Clinical Parameters

Wang, Jing-Jing,Wu, Hai-Feng,Sun, Tao,Li, Xia,Wang, Wei,Tao, Li-Xin,Huo, Da,Lv, Ping-Xin,He, Wen,Guo, Xiu-Hua Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.10

Lung cancer, one of the leading causes of cancer-related deaths, usually appears as solitary pulmonary nodules (SPNs) which are hard to diagnose using the naked eye. In this paper, curvelet-based textural features and clinical parameters are used with three prediction models [a multilevel model, a least absolute shrinkage and selection operator (LASSO) regression method, and a support vector machine (SVM)] to improve the diagnosis of benign and malignant SPNs. Dimensionality reduction of the original curvelet-based textural features was achieved using principal component analysis. In addition, non-conditional logistical regression was used to find clinical predictors among demographic parameters and morphological features. The results showed that, combined with 11 clinical predictors, the accuracy rates using 12 principal components were higher than those using the original curvelet-based textural features. To evaluate the models, 10-fold cross validation and back substitution were applied. The results obtained, respectively, were 0.8549 and 0.9221 for the LASSO method, 0.9443 and 0.9831 for SVM, and 0.8722 and 0.9722 for the multilevel model. All in all, it was found that using curvelet-based textural features after dimensionality reduction and using clinical predictors, the highest accuracy rate was achieved with SVM. The method may be used as an auxiliary tool to differentiate between benign and malignant SPNs in CT images.

The Value of Reverse Mortgage Loans: Case Study of the Chinese Market

Ping Wang,Ji-Pyo Kim 한국유통과학회 2014 The Journal of Asian Finance, Economics and Busine Vol.1 No.4

This study contributes to addressing the problem of an aging population by providing important information that determines feasible monthly payments for the clients of Chinese reverse mortgage products and by promoting the implementation of reverse mortgages in China. The variables used in this study include mean values obtained from time series data, of the rate of increase of housing prices, and the probability value, interest rate, and mortality rate obtained through the geometric Brownian motion (GBM). For mortality rates, China Life Insurance female mortality rates (2000-2003) were used. This study aims to apply the main variables that affect reverse mortgage products in a monthly payment model based on Chinese financial market conditions, and determine loan values. In this study, Shanghai’s reverse mortgage monthly payments, by age levels, were calculated through the loan-to-value (LTV) and payment (PMT) methods to evaluate the value of the reverse mortgages. Based on the optimal combination of the three factors of payment amount, loan interest rates, and the level of acceptance of prices, efforts must be made to extract the best value for the elderly. Only in this way can the interests of both lenders and borrowers be protected, by increasing the market share and economies of scale of the reverse mortgage industry and effectively improving the living standards of the elderly.

A Bidirectional Three-level DC-DC Converter with a Wide Voltage Conversion Range for Hybrid Energy Source Electric Vehicles

Ping Wang,Chendong Zhao,Yun Zhang,Jing Li,Yongping Gao 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.2

In order to meet the increasing needs of the hybrid energy source system for electric vehicles, which demand bidirectional power flow capability with a wide-voltage-conversion range, a bidirectional three-level DC-DC converter and some control strategies for hybrid energy source electric vehicles are proposed. The proposed topology is synthesized from Buck and Boost three-level DC-DC topologies with a high voltage-gain and non-extreme duty cycles, and the bidirectional operation principle is analyzed. In addition, the inductor current ripple can be effectively reduced within the permitted duty cycle range by the coordinated control between the current fluctuation reduction and the non-extreme duty cycles. Furthermore, benefitting from duty cycle disturbance control, series-connected capacitor voltages can also be well balanced, even with the discrepant rise and fall time of power switches and the somewhat unequal capacitances of series-connected capacitors. Finally, experiment results of the bidirectional operations are given to verify the validity and feasibility of the proposed converter and control strategies. It is shown to be suitable for hybrid energy source electric vehicles.

MicroRNA-214 Regulates the Acquired Resistance to Gefitinib via the PTEN/AKT Pathway in EGFR-mutant Cell Lines

Wang, Yong-Sheng,Wang, Yin-Hua,Xia, Hong-Ping,Zhou, Song-Wen,Schmid-Bindert, Gerald,Zhou, Cai-Cun Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.1

Patients with non-small cell lung cancer (NSCLC) who have activating epidermal growth factor receptor (EGFR) mutations derive clinical benefit from treatment with EGFR-tyrosine kinase inhibitors ((EGFR-TKIs)-namely gefitinib and erlotinib. However, these patients eventually develop resistance to EGFR-TKIs. Despite the fact that this acquired resistance may be the result of a secondary mutation in the EGFR gene, such as T790M or amplification of the MET proto-oncogene, there are other mechanisms which need to be explored. MicroRNAs (miRs) are a class of small non-coding RNAs that play pivotal roles in tumorigenesis, tumor progression and chemo-resistance. In this study, we firstly successfully established a gefitinib resistant cell line-HCC827/GR, by exposing normal HCC827 cells (an NSCLC cell line with a 746E-750A in-frame deletion of EGFR gene) to increasing concentrations of gefitinib. Then, we found that miR-214 was significantly up-regulated in HCC827/GR. We also showed that miR-214 and PTEN were inversely expressed in HCC827/GR. Knockdown of miR-214 altered the expression of PTEN and p-AKT and re-sensitized HCC827/GR to gefitinib. Taken together, miR-214 may regulate the acquired resistance to gefitinib in HCC827 via PTEN/AKT signaling pathway. Suppression of miR-214 may thus reverse the acquired resistance to EGFR-TKIs therapy.

A Case of Atrophic Dermatofibrosarcoma Protuberans

Ping Wang,Jian-Xia Xiong,Ai-Jun Chen,Tao Cai 대한피부과학회 2022 Annals of Dermatology Vol.34 No.5

. 영문 초록 없음

A bidirectional DC/DC converter with wide-voltage gain range and low-voltage stress for hybrid-energy storage systems in electric vehicles

Wang, Zhishuang,Wang, Ping,Bi, Huakun,Qiu, Mingjie The Korean Institute of Power Electronics 2020 JOURNAL OF POWER ELECTRONICS Vol.20 No.1

In this paper, a bidirectional non-isolated DC/DC converter for hybrid energy storage systems has been proposed. The converter is constituted by the integration of two conventional two-level topologies, with a parallel connection on their low-voltage sides (LVSs) and a series connection on their high-voltage sides (HVSs). Thus, a high-voltage gain can be achieved, along with the low-voltage stresses on power switches and capacitors. In addition, by establishing a higher charging/discharging voltage in the step-up/down mode on the inductor, the voltage gain range can be further extended. Furthermore, the operating principles, characteristics analysis, and comparisons with other converters are presented in detail. Finally, a 400 W prototype has been fabricated to further validate the feasibility and correctness of the theoretical analyses. The LVS voltage range is 20-60 V, while the HVS voltage is 200 V. The resulting voltage gain range is from 3.34 to 10. Moreover, the converter achieves high efficiency in bidirectional operations. The maximum efficiencies are 95.7% in the step-up mode and 95.9% in the step-down mode.