In Vitro Screening for Compounds Derived from Traditional Chinese Medicines with Antiviral Activities Against Porcine Reproductive and Respiratory Syndrome Virus

( Jia Cheng ),( Na Sun ),( Xin Zhao ),( Li Niu ),( Mei Qin Song ),( Yao Gui Sun ),( Jun Bing Jiang ),( Jian Hua Guo2 ),( Yuan Sheng Bai ),( Jun Ping He ),( Hong Quan Li ) 한국미생물 · 생명공학회 2013 Journal of microbiology and biotechnology Vol.23 No.8

Seventeen compounds derived from traditional Chinese medicines (TCMs) were tested for their antiviral activity against porcine reproductive and respiratory syndrome virus (PRRSV) in vitro. Visualization with the cytopathologic effect (CPE) assay and the 3-(4, 5-dimethyithiazol- 2-yl)-2,5-diphenyltetrazolium bromide test were used to determine the 50% cytotoxic concentration (CC50) and 50% effective concentration (EC50) in cultured Marc-145 cells. Among the tested compounds, chlorogenic acid and scutellarin showed potential anti-PRRSV activity. The EC50 values were 270.8 ± 14.6 μg/ml and 28.21 ± 26.0 μg/ml and the selectivity indexes were >5.54 and 35.5, respectively. The time-of-addition and virucidal assay indicated that the anti-PRRSV activity of the two compounds could be due to their inhibiting the early stage of virus replication and/or inactivating the virus directly. The inhibition of the virus attachment was not observed in the adsorption inhibition assay. The inhibition ratios of chlorogenic acid and scutellarin were, respectively, 90.8% and 61.1% at the maximum non-cytotoxic concentrations. The results have provided a basis for further exploration of their antiviral properties and mechanisms in vivo. We believe that the chlorogenic acid and scutellarin have a great potential to be developed as new anti-PRRSV drugs for clinical application.

Mechanical behavior of rock-coal-rock specimens with different coal thicknesses

Guo, Wei-Yao,Tan, Yun-Liang,Yu, Feng-Hai,Zhao, Tong-Bin,Hu, Shan-Chao,Huang, Dong-Mei,Qin, Zhe Techno-Press 2018 Geomechanics & engineering Vol.15 No.4

To explore the influence of coal thickness on the mechanical behavior and the failure characteristics of rock-coal-rock (RCR) mass, the experimental investigation of uniaxial compressive tests was conducted first and then a systematic numerical simulation by particle flow code (PFC2D) was performed to deeply analyze the failure mechanical behavior of RCR specimens with different coal thicknesses in conventional compression tests. The overall elastic modulus and peak stress of RCR specimens lie between the rock and the coal. Inter-particle properties were calibrated to match the physical sample strength and the stiffness response. Numerical simulation results show that the deformation and strength behaviors of RCR specimens depend not only on the coal thickness, but also on the confining pressure. Under low confining pressures, the overall failure mechanism of RCR specimen is the serious damage of coal section when the coal thickness is smaller than 30 mm, but it is shear failure of coal section when the coal thickness is larger than 30 mm. Whereas under high confining pressures, obvious shear bands exist in both the coal section and the rock section when the coal thickness is larger than 30 mm, but when the coal thickness is smaller than 30mm, the failure mechanism is serious damage of coal section and shear failure of rock section.

Analysis of DNA methylation in tissues and development stages of pearl oyster Pinctada fucata

Yao-guo Li,Yun-yan Guan,Qin Li,Mao-xian He 한국유전학회 2015 Genes & Genomics Vol.37 No.3

In this study, we developed a methylationsensitiveamplification polymorphism technique to investigateDNA methylation profiles in different tissues and inthe early-development stages of the pearl oyster Pinctadafucata (P. fucata). Methylation levels in adductor muscle,digestive gland, axe foot, heart, and gill ranged from 11.71to 14.71 %, and significant differences (P\0.05) betweenmethylation levels in different tissues were observed. TheDNA methylation levels of sperm, egg cells, two-cellembryos, morula embryos, trochophore larvae andD-shaped larvae were 13.51, 11.80, 12.14, 12.60, 14.65 and13.18 %, respectively. Development stages of two-cellembryos, morula embryos, trochophore larvae andD-shaped larvae indicated a higher number of identicalDNA methylation status loci in the egg, compared to that inthe sperm. It is probable that DNA methylation patterns ofthe progeny are mainly influenced by the egg, while thesperm may become increasingly important during theprocess of early embryo development. The observeddifferences in methylation levels in the tissues and thedevelopment stages of P. fucata suggest that DNA methylationmay act as an epigenetic regulator during tissuedifferentiation, individual growth, and development.

Numerical simulation of relation between interface topography and residual stress in thermal barrier coatings

Yao, Guo-Feng,Ma, Hong-Mei,Zhang, Lin-Wen Techno-Press 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.29 No.4

With respect to thermal barrier coating, the analysis of interface cohesion and residual stress is important to the life of TBC from mechanical view point. Up to now, there is not a model of describing interface cohesion. In the paper, we give a simple model of computing residual stress and study the residual stress of TBC with ANSYS. The distribution of the residual stress in different interface topography and the relationship between the residual stress and the interface topography dimension are presented.

Experimental behaviours of steel tube confined concrete (STCC) columns

Guo-Huang Yao,Qing Yu,Lin-Hai Han,Zhi-Bo Chen 국제구조공학회 2005 Steel and Composite Structures, An International J Vol.5 No.6

In recent years, the use of steel tube confined concrete (STCC) columns has been the interests of many structural engineers. The present study is an attempt to study the monotonic and cyclic behaviours of STCC columns. For the monotonic behaviours, a series of tests on STCC stub columns (twenty one), and beam-columns (twenty) were carried out. The main parameters varied in the tests are: (1) column section types, circular and square; (2) tube diameter (or width) to thickness ratio, from 40 to 162, and (3) load eccentricity ratio (e/r), from 0 to 0.5. For the cyclic behaviours, the test parameters included the sectional types and the axial load level (n). Twelve STCC column specimens, including 6 specimens with circular sections and 6 specimens with square sections were tested under constant axial load and cyclically increasing flexural loading. Comparisons are made with predicted column strengths and flexural stiffness using the existing codes. It was found that STCC columns exhibit very high levels of energy dissipation and ductility, particularly when subjected to high axial loads. Generally, the energy dissipation ability of the columns with circular sections was much higher than those of the specimens with square sections. Comparisons are made with predicted column strengths and flexural stiffness using the existing codes such as AIJ-1997, AISCLRFD- 1994, BS5400-1979 and EC4-1994.

Modal control algorithm on optimal control of intelligent structure shape

Yao, Guo Feng,Chen, Su Huan,Wang, Wei Techno-Press 2003 Structural Engineering and Mechanics, An Int'l Jou Vol.15 No.4

In this paper, a new block iterative algorithm is presented by using the special feature of the continuous Riccati equation in the optimal shape control. Because the real-time control require that the CPU time should be as short as possible, an appropriate modal control algorithm is sought. The computing cost is less than the one of the all state feedback control. A numerical example is given to illustrate the algorithm.

Numerical simulation of relation between interface topography and residual stress in thermal barrier coatings

Guo-Feng Yao,Hong-Mei Ma,Lin-wen Zhang 국제구조공학회 2008 Structural Engineering and Mechanics, An Int'l Jou Vol.29 No.4

With respect to thermal barrier coating, the analysis of interface cohesion and residual stress is important to the life of TBC from mechanical view point. Up to now, there is not a model of describing interface cohesion. In the paper, we give a simple model of computing residual stress and study the residual stress of TBC with ANSYS. The distribution of the residual stress in different interface topography and the relationship between the residual stress and the interface topography dimension are presented.

4-Hydroxynonenal Promotes Growth and Angiogenesis of Breast Cancer Cells through HIF-1α Stabilization

Li, Yao-Ping,Tian, Fu-Guo,Shi, Peng-Cheng,Guo, Ling-Yun,Wu, Hai-Ming,Chen, Run-Qi,Xue, Jin-Ming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

4-Hydroxynonenal (4-HNE) is a stable end product of lipid peroxidation, which has been shown to play an important role in cell signal transduction, while increasing cell growth and differentiation. 4-HNE could inhibit phosphatase and tensin homolog (PTEN) activity in hepatocytes and increased levels have been found in human invasive breast cancer. Here we report that 4-HNE increased the cell growth of breast cancer cells as revealed by colony formation assay. Moreover, vascular endothelial growth factor (VEGF) expression was elevated, while protein levels of hypoxia inducible factor 1 alpha (HIF-$1{\alpha}$) were up-regulated. Sirtuin-3 (SIRT3), a major mitochondria NAD+-dependent deacetylase, is reported to destabilize HIF-$1{\alpha}$. Here, 4-HNE could inhibit the deacetylase activity of SIRT3 by thiol-specific modification. We further demonstrated that the regulation by 4-HNE of levels of HIF-$1{\alpha}$ and VEGF depends on SIRT3. Consistent with this, 4-HNE could not increase the cell growth in SIRT3 knockdown breast cancer cells. Additionally, 4-HNE promoted angiogenesis and invasion of breast cancer cells in a SIRT3-dependent manner. In conclusion, we propose that 4-HNE promotes growth, invasion and angiogenesis of breast cancer cells through the SIRT3-HIF-$1{\alpha}$-VEGF axis.

Robust Adaptive Dynamic Surface Control of Multi-link Flexible Joint Manipulator with Input Saturation

Wei Yao,Yu Guo,Yi-Fei Wu,Jian Guo 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.2

This paper investigates the tracking control for multi-link flexible joint manipulator system with disturbance, uncertain stiffness and input saturation. A robust adaptive dynamic surface control scheme is developed with an auxiliary dynamic system. The auxiliary dynamic system is employed to handle input saturation. To compensate for disturbance, an adaptive law for disturbance upper bound estimation is designed. The value of uncertain stiffness is updated by another adaptive law. It is proved that the proposed control scheme can realize precise tracking of link angles and guarantee the uniform ultimate boundedness of all the signals in the closed-loop by appropriately choosing the parameters to be designed. Finally, simulation results demonstrate the effectiveness of the proposed control method.

Research Articles : The Influence of Challenge on Cathepsin B and D Expression Patterns in the Silkworm Bombyx mori L

( Feng Yao Wu ),( Feng Ming Zou ),( Jun Qiang Jia ),( Sheng Peng Wang ),( Guo Zheng Zhang ),( Xi Jie Guo ),( Zhong Zheng Gui ) 한국잠사학회 2011 International Journal of Industrial Entomology Vol.23 No.1

Cathepsins are well-characterized proteases that are ubiquitously expressed in lysosomes. Previous work revealed that Bombyx mori cathepsins B and D are expressed in the fat body and undergo decomposition during larval-pupal metamorphosis. Quantitative RTPCR was performed to detect cathepsin gene expression at the transcription level when challenged by B. mori nuclear polyhedrosis virus (BmNPV), temperature and hormones (20-hydroxyecdysone (20E) and juvenile hormone analogue (JHA)). mRNAs encoding cathepsins B and D were significantly enhanced after the larvae were infected with BmNPV, and the peak of the induction appeared at 1 day before spinning. This attenuated the inducing effect on cathepsin expression caused by infection. Temperature shock induced cathepsin expression at the later stage of the 5th instar, and transcription levels varied with development stage and temperature. Cathepsin B and D mRNA expression in the fat body were significantly induced by JHA at the day before spinning, and with 20E, the expression reached a peak at the last day of the 5th instar. Cathepsin B and D mRNA expression exhibited detectable changes post-treatment, without significant differences between or among the hormone concentrations.