Study on Asymptotic Stability of Fractional Singular Systems with Time Delay

Dazi Li,Liming Wei,Tianheng Song,Qibing Jin 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.4

The stability of fractional singular systems with time delay is discussed. Considering the singularity of the system, a system is decomposed into two subsystems. Through fractional Laplacian transformation and inverse Laplacian transformation on the subsystems, the expression of the state variables in time domain is obtained. According to the characteristics of Mittag-Leffler function, some inequalities that have important influence on stability are derived. Finally, a new sufficient condition is found to make the fractional singular systems with time delay asymptotically stable when the fractional order belongs to1 < α < 2. Meanwhile, the sufficient condition is also obtained to make the system stable under the nonlinear disturbance. All processes are proved and numerical examples are provided to show the validity and feasibility of the proposed method.

Ginkgolic Acid Suppresses Nasopharyngeal Carcinoma Growth by Inducing Apoptosis and Inhibiting AKT/NF-κB Signaling

Yu Xiao,Fen Li,Anyuan Zheng,Qibing Chen,Fuhai Chen,Xiang Cheng,Zezhang Tao 한국식품영양과학회 2021 Journal of medicinal food Vol.24 No.8

Even though nasopharyngeal carcinoma (NPC) is not common worldwide, it is a major public health burden in endemic areas. Distant metastasis often leads to a poor prognosis for NPC; therefore, new and effective anticancer strategies are needed. Ginkgolic acid (GA) is small-molecule compound existing in Ginkgo biloba that has various biologically relevant activities, including antitumor properties; however, its effects and mechanism of action in NPC are unknown. The effects of GA on NPC and such underlying mechanisms were investigated using 5–8F and CNE2 cells and NP69 human immortalized nasopharyngeal epithelial cells in this study. Moreover, the xenograft models were built to examine GA's effection in vivo. GA treatment decreased the survival and invasive capacity of 5–8F and CNE2 and induced their apoptosis, which varied with dose; this was accompanied by downregulation of B cell lymphoma (Bcl)2, upregulation of Bcl2-associated X protein, and activation of poly-ADP ribose polymerase, and caspase-9/-3. G0/G1 phase arrest was induced by GA in NPCs. It also reduced the expression of cyclin-dependent kinase 6 and its regulators cyclin D2 and cyclin D3. GA inhibited the activation of protein kinase B/nuclear factor signaling; this effect was potentiated with GA and 5-fluorouracil (5-FU), which also enhanced 5-FU-induced apoptosis. In summary, GA may be effective as an adjuvant to conventional chemotherapy drugs in preventing the progression of NPC.

Triptolide downregulates Rac1 and the JAK/STAT3 pathway and inhibits colitis-related colon cancer progression

Zhipeng Wang,Haifeng Jin,Ruodan Xu,Qibing Mei,Daiming Fan 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.10

Triptolide, a diterpenoid triepoxide from the traditional Chinese medicinal herb Tripterygium wilfordii Hook. f., is a potential treatment for autoimmune diseases as well a possible anti-tumor agent. It inhibits proliferation of coloretal cancer cells in vitro and in vivo. In this study, its ability to block progress of colitis to colon cancer, and its molecular mechanism of action are investigated. A mouse model for colitis-induced colorectal cancer was used to test the effect of triptolide on cancer progression. Treatment of mice with triptolide decreased the incidence of colon cancer formation, and increased survival rate. Moreover, triptolide decreased the incidence of tumors in nude mice inoculated with cultured colon cancer cells dose-dependently. In vitro, triptolide inhibited the proliferation, migration and colony formation of colon cancer cells. Secretion of IL6 and levels of JAK1, IL6R and phosphorylated STAT3 were all reduced by triptolide treatment. Triptolide prohibited Rac1 activity and blocked cyclin D1 and CDK4 expression, leading to G1 arrest. Triptolide interrupted the IL6R-JAK/STAT pathway that is crucial for cell proliferation, survival, and inflammation. This suggests that triptolide might be a candidate for prevention of colitis induced colon cancer because it reduces inflammation and prevents tumor formation and development. Triptolide, a diterpenoid triepoxide from the traditional Chinese medicinal herb Tripterygium wilfordii Hook. f., is a potential treatment for autoimmune diseases as well a possible anti-tumor agent. It inhibits proliferation of coloretal cancer cells in vitro and in vivo. In this study, its ability to block progress of colitis to colon cancer, and its molecular mechanism of action are investigated. A mouse model for colitis-induced colorectal cancer was used to test the effect of triptolide on cancer progression. Treatment of mice with triptolide decreased the incidence of colon cancer formation, and increased survival rate. Moreover, triptolide decreased the incidence of tumors in nude mice inoculated with cultured colon cancer cells dose-dependently. In vitro, triptolide inhibited the proliferation, migration and colony formation of colon cancer cells. Secretion of IL6 and levels of JAK1, IL6R and phosphorylated STAT3 were all reduced by triptolide treatment. Triptolide prohibited Rac1 activity and blocked cyclin D1 and CDK4 expression, leading to G1 arrest. Triptolide interrupted the IL6R-JAK/STAT pathway that is crucial for cell proliferation, survival, and inflammation. This suggests that triptolide might be a candidate for prevention of colitis induced colon cancer because it reduces inflammation and prevents tumor formation and development.

Macrophage Activation by an Acidic Polysaccharide Isolated from Angelica Sinensis (Oliv.) Diels

Yang, Xingbin,Zhao, Yan,Wang, Haifang,Mei, Qibing Korean Society for Biochemistry and Molecular Biol 2007 Journal of biochemistry and molecular biology Vol.40 No.5

This study was designed to identify and characterize the mechanism of macrophage activation by AAP, an acidic polysaccharide fraction isolated from the roots of Angelica sinensis (Oliv.) Diels. As a result, AAP significantly enhanced nitric oxide (NO) production and cellular lysosomal enzyme activity in murine peritoneal macrophages in vitro and in vivo. Furthermore, L-NAME, a specific inhibitor of inducible nitric oxide synthase (iNOS), effectively suppressed AAP-induced NO generation in macrophages, indicating that AAP stimulated macrophages to produce NO through the induction of iNOS gene expression and the result was further confirmed by the experiment of the increase of AAP-induced iNOS transcription in a dose-dependent manner. To further investigate, AAP was shown to strongly augment toll-like receptor 4 (TLR4) mRNA expression and the pretreatment of macrophages with anti-TLR4 antibody significantly blocked AAP-induced NO release and the increase of iNOS activity, and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) secretion.

Fractional Order IMC Controller Design for Two-input-two-output Fractional Order System

Dazi Li,Xingyu He,Tianheng Song,Qibing Jin 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.4

Research on the fractional order system is becoming more and more popular. Most of the fractional ordercontroller design methods focus on single-input-single-output processes. In this paper, a fractional order internalmodel controller with inverted decoupling is proposed to handle non-integer order two-input-two-output systemswith time delay. The fractional order two-input-two-output (FO-TITO) process is decoupled by inverted decouplingmethod. The fractional order internal model control (IMC) is then used to simplify the tuning process. Because ofthe complexity of multiple time delay, the condition of FO-TITO process with time delay is discussed. In order toensure the robustness of the system, a Maximum sensitivity function is used to tune the parameters. Then Lyapunovstability theory is applied to verify the stability of the system. The proposed controller provides ideal performancefor both set point-tracking and disturbance rejection and is robust to process gain variations. Numerical resultsshow the performance of the proposed method.

Increased Expression of Heat Shock Protein 72 Protects Renal Proximal Tubular Cells from Gentamicin-induced Injury

Li Liu,Zhipeng Wang,Linna Liu,Yuhua Ran,Rong Zhang,Qibing Mei 대한의학회 2006 Journal of Korean medical science Vol.21 No.5

Triptolide inhibits ovarian cancer cell invasion by repression of matrix metalloproteinase 7 and 19 and upregulation of E-cadherin

Hongxi Zhao,Zhifu Yang,Xiaohong Wang,Xianzhi Zhang,Meng Wang,Yukun Wang,Qibing Mei,Zhipeng Wang 생화학분자생물학회 2012 Experimental and molecular medicine Vol.44 No.11

Triptolide, a compound extracted from the traditional Chinese medicine preparation of Tripterygium wilfordii Hook F., has been reported to have anti-inflammatory and anti-cancer activities. However, its effect on ovarian cancer invasion is unknown. We observed that MMP7 and MMP19 expression increased in ovarian cancer tissue. Triptolide treatment inhibited the migration and invasion of ovarian cancer cells SKOV3 and A2780 at the concentration of 15 nM. We also observed that triptolide suppressed MMP7 and MMP19 promoter activity in a dose-dependent manner,down-regulating the expressions of these promoters on mRNA and protein level. Moreover, triptolide enhanced E-cadherin expression in ovarian cancer cells. In vivo, triptolide inhibited tumor formation and metastasis in nude mice, and suppressed MMP7 and MMP19 expression; it also enhanced E-cadherin expression in tumor in a dose-dependent manner. Over expression of MMP7 and MMP19, or suppression of E-cadherin expression partially abolished the inhibitory effect of triptolide on invasion of ovarian cancer cells. To summarize, triptolide significantly inhibited the migration and invasion of ovarian cancer cells by suppression of MMP7 and MMP19 and up-regulation of E-cadherin expression. This study shows that triptolide is a good candidate for the treatment of ovarian cancer and reduction of metastasis.

Calcium signalling mediated the regulation of growth and polysaccharide accumulation by light quality in Dendrobium offi cinale protocorms

Ting Lei,Suping Gao,Xiao Lin,Kaihui Zhang,Yingqi Liu,Wenji Li,Di Hu,Xiaofang Yu,Mingyan Jiang,Qibing Chen,Ying Sun 한국원예학회 2021 Horticulture, Environment, and Biotechnology Vol.62 No.2

This study selected Dendrobium offi cinale protocorms as the experimental material and used diff erent light-quality treatmentsand calcium signalling inhibitors to explore the mechanism of the biological response of calcium to light quality. The results indicate that a 1:3 red:blue (R:B) light ratio promotes the accumulation of biomass and polysaccharides in theprotocorm. Nevertheless, this eff ect can be entirely counteracted by calmodulin (CaM) inhibitors and calcium ion-chelatingagents. The possible mechanisms of this eff ect are as follows: (1) The Ca 2+ -CaM signal-regulated photosynthetic apparatusis improved by the R:B 1:3 light, increasing the CaM content and Ca 2+ -ATPase activity. Thus, R:B 1:3 light increases thedevelopment of the photosynthetic apparatus in the D. offi cinale protocorm, enhances its photosynthetic productivity, andpromotes the activities of sucrose phosphatase; accordingly, biomass and sucrose accumulation increase. (2) R:B 1:3 lightenhances Ca 2+ -CaM signalling and regulates glycometabolic processes to promote the activities of sucrose synthase, thusincreasing fructose and glucose levels and providing suffi cient synthetic precursors to promote polysaccharide production.

E-beam deposited Ag-nanoparticles plasmonic organic solar cell and its absorption enhancement analysis using FDTD-based cylindrical nano-particle optical model.

Kim, Richard S,Zhu, Jinfeng,Park, Jeung Hun,Li, Lu,Yu, Zhibin,Shen, Huajun,Xue, Mei,Wang, Kang L,Park, Gyechoon,Anderson, Timothy J,Pei, Qibing Optical Society of America 2012 Optics express Vol.20 No.12

<P>We report the plasmon-assisted photocurrent enhancement in Ag-nanoparticles (Ag-NPs) embedded PEDOT:PSS/P3HT:PCBM organic solar cells, and systematically investigate the causes of the improved optical absorption based on a cylindrical Ag-NPs optical model which is simulated with a 3-Dimensional finite difference time domain (FDTD) method. The proposed cylindrical Ag-NPs optical model is able to explain the optical absorption enhancement by the localized surface plasmon resonance (LSPR) modes, and to provide a further understanding of Ag-NPs shape parameters which play an important role to determine the broadband absorption phenomena in plasmonic organic solar cells. A significant increase in the power conversion efficiency (PCE) of the plasmonic solar cell was experimentally observed and compared with that of the solar cells without Ag-NPs. Finally, our conclusion was made after briefly discussing the electrical effects of the fabricated plasmonic organic solar cells.</P>