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Chemical Composition, Antioxidant and Cytoprotective Activities of Lotus Receptacle
Weicheng Hu,Gongcheng Wang,Ting Shen,Yuning Wang,Boran Hu,Xinfeng Wang,Lei Wu,Pengxia Li,Lilian Ji 한국원예학회 2015 Horticulture, Environment, and Biotechnology Vol.56 No.5
The nutritional composition (ash, protein, fat, crude fiber, and carbohydrate) and antioxidant activity of lotus receptacles (LRs) were studied. The LRs contained 88.25% carbohydrates, 22.90% crude fiber, 5.79% crude ash, 0.77% crude protein content, and 5.19% crude lipid on a dry weight basis. The ethanolic extract of lotus receptacle (ELR) exerted strong scavenging effects on 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical, hydroxyl radical (•OH), superoxide anion (O2-), and hydrogen peroxide (H2O2), as well as high reducing power. ELR pretreatment effectively elevated cell viability and decreased malondialdehyde (MDA) levels in H2O2-treated RAW 264.7 cells. Additionally, ELR had high phenolic and flavonoid contents with values of 318.15 mg gallic acid equivalent/g and 239.06 mg rutin equivalent/g, respectively. Moreover, the bioactivity-guided study of ELR resulted in the isolation and identification of quercetin-3-O-β-D-glucopyranoside (QOG), a dietary flavonoid. QOG exhibited strong DPPH free radical scavenging activity, with an IC50 value of 24.26 μM; docking studies revealed that QOC formed one hydrogen bond with LYS263 in the active site, suggesting it is, in part, responsible for the free activity of LR.
Li, Hui,Wang, Beibei,Yang, Acong,Lu, Rui,Wang, Weicheng,Zhou, Yang,Shi, Guilai,Kwon, Sung Won,Zhao, Yingming,Jin, Ying Wiley (John WileySons) 2009 Stem Cells Vol.27 No.6
<P>Embryonic stem cells (ESCs) possess the capacity to self-renew and differentiate into all cell types of an organism. It is essential to understand how these properties are controlled for the potential usage of their derivatives in clinical settings and reprogramming of differentiated somatic cells. Although transcriptional factors, such as Oct4, Sox2, and Nanog, have been considered as a part of the core regulatory circuitry, a growing body of evidence suggests that additional factors exist and contribute to the control of ESC self-renewal and differentiation. Here, we report that Ly-1 antibody reactive clone (LYAR), a zinc finger nucleolar protein highly expressed in undifferentiated ESCs, plays a critical role in maintaining ESC identity. Its downregulation significantly reduces the rate of ESC growth and increases their apoptosis. Moreover, reduced expression of LYAR in ESCs impairs their differentiation capacity, failing to rapidly silence pluripotency markers and to activate differentiation genes upon differentiation. Mechanistically, LYAR forms a complex with another nucleolar protein, nucleolin, and prevents its self-cleavage, maintaining a normal steady-state level of nucleolin protein in undifferentiated ESCs. Interestingly, the downregulation of nucleolin is detrimental to the growth of ESCs and increases the rate of apoptosis, similarly to the knockdown of LYAR. Thus, our data emphasize the fact that other genes besides Oct4 and Nanog are uniquely required for ESC self-renewal and differentiation and demonstrate that LYAR functions to control the stability of nucleolin protein, which in turn is essential for maintaining the self-renewal of ESCs.</P>
An improved procedure for generating standardised load-time histories for marine structures
Li, Shanshan,Cui, Weicheng,Paik, Jeom Kee SAGE Publications 2016 Proceedings of the Institution of Mechanical Engin Vol.230 No.2
<P>The load sequence effect has been proved from laboratory tests to be an influencing factor that cannot be neglected in the fatigue analysis of marine structures. To take account of this significant factor, fatigue life prediction should be based on fatigue crack propagation theory rather than the currently used cumulative fatigue damage theory. Accordingly, fatigue loading needs to be provided as the load-time history in the time domain rather than the load spectrum in the frequency domain. A general procedure for generating the standardised load-time history for marine structures based on a short-term load measurement has been proposed by the authors. This article seeks to further improve on this procedure and explain how to apply the determined standardised load-time history in the fatigue life prediction method based on the fatigue crack propagation theory. Finally, generation and application of a standardised load-time history are given for a tubular T-joint of an offshore platform, which demonstrates the practical and effective use of the proposed approach.</P>
Weicheng Han,Tieying Li 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.9
Lucheng City has a long history, and now is the only county-level city which belongs to Shanxi Province. This city has a small population of people which are relatively concentrated. The economy of this city is based on the coal industry, which results in the fact that the secondary industry dominates while the primary and tertiary ones obviously fall behind. To respond to the call of our nation, which is that ‘balance the development between the urban and rural’, and to meet the needs of the urban development, it is essential to make some detailed strategies. Especially, the construction of the landscape green space system plays an important role in this process. This paper focuses on the drainage purposes of this system. In addition, to enhance this city’s drainage function, it is also demanding to optimize its drainage system, which in this paper we concentrate on the urban sewer system. In this paper, we apply two mathematical models into the drainage analysis and optimization, which are the soil water characteristic curve (SWCC) method and urban sewer system model (USSM), respectively.
Fuli Li,Yufeng Cao,Tingwu Liu,Guilong Yan,Liang Chen,Lilian Ji,Lun Wang,Bin Chen,Aftab Yaseen,Ashfaq A. Khan,Guo-Lin Zhang,Yunyao Jiang,Jianxun Liu,Gongcheng Wang,Ming-Kui Wang,Weicheng Hu 고려인삼학회 2019 Journal of Ginseng Research Vol.43 No.4
Background: The leaves and roots of Panax ginseng are rich in ginsenosides. However, the chemical compositionsof the leaves and roots of P. ginseng differ, resulting in different medicinal functions. In recent years,the aerial parts of members of the Panax genus have received great attention fromnatural product chemistsas producers of bioactive ginsenosides. The aim of this study was the isolation and structural elucidation ofnovel, minor ginsenosides in the leaves of P. ginseng and evaluation of their antiinflammatory activity in vitro. Methods: Various chromatographic techniques were applied to obtain pure individual compounds, andtheir structures were determined by nuclear magnetic resonance and high-resolution mass spectrometry,as well as chemical methods. The antiinflammatory effect of the new compounds was evaluated onlipopolysaccharide-stimulated RAW 264.7 cells. Results and conclusions: Two novel, minor triterpenoid saponins, ginsenoside LS1 (1) and 5,6-didehydroginsenoside Rg3 (2), were isolated from the leaves of P. ginseng. The isolated compounds 1and 2 were assayed for their inhibitory effect on nitric oxide production in LPS-stimulated RAW 264.7cells, and Compound 2 showed a significant inhibitory effect with IC50 of 37.38 mM compared with that ofNG-monomethyl-L-arginine (IC50 ¼ 90.76 mM). Moreover, Compound 2 significantly decreased secretionof cytokines such as prostaglandin E2 and tumor necrosis factor-a. In addition, Compound 2 significantlysuppressed protein expression of inducible nitric oxide synthase and cyclooxygenase-2. These resultssuggested that Compound 2 could be used as a valuable candidate for medicinal use or functional food,and the mechanism is warranted for further exploration.
Shen, Ting,Li, Xueqin,Hu, Weicheng,Zhang, Lijin,Xu, Xudong,Wu, Haifeng,Ji, Lilian 한국응용생명화학회 2015 Applied Biological Chemistry (Appl Biol Chem) Vol.58 No.4
The extraction and solvent partition of roots of Incarvillea compacta, a traditional Tibetan folk medicine, and repeated column chromatography and preparative high-performance liquid chromatography for n-butanol fraction yielded four phenylethanoid glycosides, crenatoside (1), 3'''-O-methylcrenatoside (2), leucoseceptoside A (3), and martynoside (4). The chemical structures were identified on the basis of spectroscopic data analyses including NMR and MS. All compounds were isolated for the first time from the plant. Compound 1 exerted better 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activity. In addition, compounds 1-4 were evaluated for their hepatoprotective activity on carbon tetrachloride ($CCl_4$)-induced liver injury in HepG2 cells. Pretreatment of HepG2 cells with compound 1-4 significantly increased the viability on $CCl_4$-induced cell death. Furthermore, compounds 1-4 also alleviated $CCl_4$-induced hepatotoxicity by enhancement of the antioxidant enzyme activities of superoxide dismutase and reduction of the malondialdehyde content, intracellular ROS as well as NF-${\kappa}B$ transactivation. Our results suggest that phenylethanoid glycosides ameliorate $CCl_4$-induced cell injury, and this protection was likely due to antioxidative activity and down-regulation of NF-${\kappa}B$.
Xiaodong Yu,Weicheng Gao,Yanan Feng,Guangqiang Shi,Shihao Li,Minmin Chen,Ruiming Zhang,Junfeng Wang,Wentao Jia,Jianhua Jiao,Ruichun Dai 한국정밀공학회 2023 International Journal of Precision Engineering and Vol.24 No.6
Hydrostatic bearing has the advantages of wide speed range, large bearing capacity, high precision and stability. Hydrostatic-hydrodynamic hybrid bearing can make up for the lack of stiffness of hydrostatic bearing and prevent tribological failure under the condition of high speed and heavy load. Therefore, hydrostatic bearing and hydrostatic-hydrodynamic hybrid bearing have become important bearing parts of high-end computer numerical control (CNC) machine equipment. The research on hydrostatic and hydrostatic-hydrodynamic open a new way for precision improvement of high-end CNC machine equipment. This paper reviews research progress of hydrostatic linear guideway, hydrostatic rest and ram, hydrostatic thrust bearing, hydrostatic-hydrodynamic thrust bearing and hydrostatic-hydrodynamic spindle of high-end CNC machine equipment, and discusses the influence of structure and working parameters on lubrication performance, accuracy and stability of bearing parts. Finally, the future research direction in hydrostatic bearing and hydrostatic-hydrodynamic hybrid bearing are suggested. This review provides a theoretical basis for design and development of high-end CNC machine equipment in the future.
Qiong Wu,Linquan Bai,Weicheng Liu,Yingying Li,Caige Lu,Yaqian Li,Kehe Fu,Chuanjin Yu,Jie Chen 한국미생물학회 2013 The journal of microbiology Vol.51 No.2
Streptomyces lydicus A01 and Trichoderma harzianum P1are potential biocontrol agents of fungal diseases in plants. S. lydicus A01 produces natamycin to bind the ergosterol of the fungal cell membrane and inhibits the growth of Botrytis cinerea. T. harzianum P1, on the other hand, features high chitinase activity and decomposes the chitin in the cell wall of B. cinerea. To obtain the synergistic biocontrol effects of chitinase and natamycin on Botrytis cinerea, this study transformed the chit42 gene from T. harzianum P1 to S. lydicus A01. The conjugal transformant (CT) of S. lydicus A01 with the chit42 gene was detected using polymerase chain reaction (PCR). Associated chitinase activity and natamycin production were examined using the 3, 5-dinitrosalicylic acid (DNS)method and ultraviolet spectrophotometry, respectively. The S. lydicus A01-chit42 CT showed substantially higher chitinase activity and natamycin production than its wild type strain (WT). Consequently, the biocontrol effects of S. lydicus A01-chit42 CT on B. cinerea, including inhibition to spore germination and mycelial growth, were highly improved compared with those of the WT. Our research indicates that the biocontrol effect of Streptomyces can be highly improved by transforming the exogenous resistance gene, i.e. chit42from Trichoderma, which not only enhances the production of antibiotics, but also provides a supplementary function by degrading the cell walls of the pathogens.