Arylazolyl(azinyl)thioacetanilide. Part 9#: Synthesis and Biological Investigation of Thiazolylthioacetamides Derivatives as a Novel Class of Potential Antiviral Agents

Peng Zhan,Xinyong Liu,Liu Wang,Hong Liu,Xuwang Chen,Xiao Li,Xin Jiang,Qiangqiang Zhang,Christophe Pannecouque,Lieve Naesens,Erik De Clercq,Ailin Liu,Guanhua Du 대한약학회 2012 Archives of Pharmacal Research Vol.35 No.6

In continuation of our endeavor to develop new, potent, selective and less toxic antiviral agents, a novel series of 2-(2-amino/chloro-4-(2,4-dibromophenyl) thiazol-5-ylthio)acetamide derivatives was synthesized via an expeditious route and evaluated for their anti-HIV activities against wild-type virus and clinically relevant mutant strains, and for their anti-influenza virus activities against influenza A (H1N1 and H3N2) and influenza B in cellular assays. The selected active compounds were also assayed for their enzymic inhibitory activities. The results showed that some 2-chloro substituted thiazolylthioacetamide derivatives possessed potent activity against wild type HIV-1 and several key mutant strains (E138K, K103N, L100I) of HIV-1 in MT-4 cells with EC50 values in micromolar range. Two 2-amino substituted thiazole derivatives 8a7 and 8a8 displayed significant potency against influenza A/H1N1 in MDCK cells with EC50 values much lower than that of oseltamivir carboxylate, ribavirin, amantadine and rimantadine. Though the mechanism of actions is still unclear, these novel thiazolylthioacetamides might serve as original leads for further pharmacological investigations as potential therapeutic agents against HIV-1 or influenza virus.

FRAME AND LATTICE SAMPLING THEOREM FOR SUBSPACES OF L2(R)

Zhan-wei Liu,Guo-en Hu 한국전산응용수학회 2009 Journal of applied mathematics & informatics Vol.27 No.1

In this paper, a necessary and sufficient condition for lattice sampling theorem to hold for frame in subspaces of L2(R) is established. In addition, we obtain the formula of lattice sampling function in frequency space. Furthermore, by discussing the parameters in Theorem 3.1, some corresponding corollaries are derived. In this paper, a necessary and sufficient condition for lattice sampling theorem to hold for frame in subspaces of L2(R) is established. In addition, we obtain the formula of lattice sampling function in frequency space. Furthermore, by discussing the parameters in Theorem 3.1, some corresponding corollaries are derived.

Effects of alfalfa flavonoids on the production performance, immune system, and ruminal fermentation of dairy cows

Zhan, Jinshun,Liu, Mingmei,Su, Xiaoshuang,Zhan, Kang,Zhang, Chungang,Zhao, Guoqi Asian Australasian Association of Animal Productio 2017 Animal Bioscience Vol.30 No.10

Objective: The objective of this study was to examine the effects of alfalfa flavonoids on the production performance, immunity, and ruminal fermentation of dairy cows. Methods: The experiments employed four primiparous Holstein cows fitted with ruminal cannulas, and used a $4{\times}4$ Latin square design. Cattle were fed total mixed ration supplemented with 0 (control group, Con), 20, 60, or 100 mg of alfalfa flavonoids extract (AFE) per kg of dairy cow body weight (BW). Results: The feed intake of the group receiving 60 mg/kg BW of AFE were significantly higher (p<0.05) than that of the group receiving 100 mg/kg BW. Milk yields and the fat, protein and lactose of milk were unaffected by AFE, while the total solids content of milk reduced (p = 0.05) linearly as AFE supplementation was increased. The somatic cell count of milk in group receiving 60 mg/kg BW of AFE was significantly lower (p<0.05) than that of the control group. Apparent total-tract digestibility of neutral detergent fiber and crude protein showed a tendency to increase (0.05<$p{\leq}0.10$) with ingestion of AFE. Methane dicarboxylic aldehyde concentration decreased (p = 0.03) linearly, whereas superoxide dismutase activity showed a tendency to increase (p = 0.10) quadratically, with increasing levels of AFE supplementation. The lymphocyte count and the proportion of lymphocytes decreased (p = 0.03) linearly, whereas the proportion of neutrophil granulocytes increased (p = 0.01) linearly with increasing levels of dietary AFE supplementation. The valeric acid/total volatile fatty acid (TVFA) ratio was increased (p = 0.01) linearly with increasing of the level of AFE supplementation, the other ruminal fermentation parameters were not affected by AFE supplementation. Relative levels of the rumen microbe Ruminococcus flavefaciens tended to decrease (p = 0.09) quadratically, whereas those of Butyrivibrio fibrisolvens showed a tendency to increase (p = 0.07) quadratically in response to AFE supplementation. Conclusion: The results of this study demonstrate that AFE supplementation can alter composition of milk, and may also have an increase tendency of nutrient digestion by regulating populations of microbes in the rumen, improve antioxidant properties by increasing antioxidant enzyme activities, and affect immunity by altering the proportions of lymphocyte and neutrophil granulocytes in dairy cows. The addition of 60 mg/kg BW of AFE to the diet of dairy cows was shown to be beneficial in this study.

FRAME AND LATTICE SAMPLING THEOREM FOR SUBSPACES OF $L^2$��

Liu, Zhan-Wei,Hu, Guo-En The Korean Society for Computational and Applied M 2009 Journal of applied mathematics & informatics Vol.27 No.1

In this paper, a necessary and sufficient condition for lattice sampling theorem to hold for frame in subspaces of $L^2$(R) is established. In addition, we obtain the formula of lattice sampling function in frequency space. Furthermore, by discussing the parameters in Theorem 3.1, some corresponding corollaries are derived.

Effect of External Heat Input on Fluid Sloshing Dynamic Performance in a Liquid Oxygen Tank

Liu Zhan,Feng Yuyang,Liu Yuanliang,Yan Jia,Li Yanzhong 한국항공우주학회 2020 International Journal of Aeronautical and Space Sc Vol.21 No.4

In the present study, a numerical model is developed to research the effect of the heat input on fluid sloshing. The volume of fluid method is used to simulate fluid reciprocating motion during sloshing with the mesh motion treatment being coupled. The external sloshing excitation is realized by user-defined functions and the convection thermal boundary condition is adopted to consider the heat exchange between the tank and the external environment. The model validation is made with the relative error being less than five percent. Based on the developed numerical model, the variation of fluid pressure, interface fluctuation, fluid sloshing hydrodynamics and fluid temperature distribution are, respectively, analyzed. Some conclusions are obtained finally. The present study is significant to the fluid sloshing suppression in cryogenic fuel storage tanks.

Numerical Study on Thermodynamic Performance in a Cryogenic Fuel Storage Tank Under External Sloshing Excitation

Zhan Liu,Hong Chen,Qiang Chen,Liubiao Chen 한국항공우주학회 2021 International Journal of Aeronautical and Space Sc Vol.22 No.5

Fluid sloshing usually causes some serious safety issues during the transportation and utilization of liquid fuel in different engineering applications. In this paper, a computational fluid dynamics model is established to investigate the thermal physical process and sloshing hydrodynamics in a cryogenic fuel storage tank. Both the experimental validation and calculation grid sensitive analysis are conducted. The present numerical calculation model was turned out to be acceptable and proper for fluid sloshing prediction. Based on the proposed numerical model, the sloshing force and moment, the tank pressure variation, the fluid temperature distribution and the dynamic response of the free surface are investigated and analyzed respectively. The results show that the sinusoidal excitation has obvious influences on the thermodynamic and hydrodynamics performance in cryogenic fuel storage tanks. With some valuable conclusions obtained, this study is of significance to the depth understanding on the non-isothermal fluid sloshing, and may supply some technique supports for the safety design of cryogenic storage tanks.

Effect of Contact Pressure on Reciprocating Wear Behavior of PEEK, PTFE, and UHMWPE

Liu Lian,Duan Haitao,Jia Dan,Tu Jiesong,Zhan Shengpeng,Li Yinhua,Luo Xiaoshuang,Zhan Wen,Xiong Wei,Li Jian 한국고분자학회 2020 폴리머 Vol.44 No.6

Engineering plastics are macromolecular compounds composed of covalently bonded macromolecules, which have been widely used in sliding wear-resistance materials in isolation bearings. In this study, an MFT-5000 reciprocating friction testing machine was used to compare the friction and wear performance of polyetheretherketone (PEEK), polytetrafluoroethylene (PTFE), and ultra-high molecular weight polyethylene (UHMWPE) under heavy load conditions in dry friction condition. The results show that load has a significant effect on the friction coefficient, wear rate, and wear mechanism of three materials. The instant friction coefficient of PTFE fluctuates under high load, the wear rate clearly increases with the increase in load. Therefore, the application under high load conditions is limited. The wear rate of UHMWPE is the least affected by the load among the three materials. Even when the load exceeds the yield strength, the wear resistance is still good. The friction coefficient of PEEK decreases with the increase in load but maintains a high value that restricts its application in sliding friction pair materials to some degree.

The Influence of Pruning on the Blossom of Wild Rhododendrons

Liu Zhan-chao 한국원예학회 2006 한국원예학회 기타간행물 Vol.- No.-

β-Elemene Induces Apoptosis in Human Renal-cell Carcinoma 786-0 Cells through Inhibition of MAPK/ERK and PI3K/Akt/mTOR Signalling Pathways

Zhan, Yun-Hong,Liu, Jing,Qu, Xiu-Juan,Hou, Ke-Zuo,Wang, Ke-Feng,Liu, Yun-Peng,Wu, Bin Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.6

Background: Renal-cell carcinoma (RCC) is resistant to almost all chemotherapeutics and radiation therapy. ${\beta}$-Elemene, a promising anticancer drug extracted from a traditional Chinese medicine, has been shown to be effective against various tumors. In the present study, anti-tumor effects on RCC cells and the involved mechanisms were investigated. Methods: Human RCC 786-0 cells were treated with different concentrations of ${\beta}$-elemene, and cell viability and apoptosis were measured by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide (MTT) assay and flow cytometry, respectively. Protein expression was assayed by western blotting. Autophagy was evaluated by transmission electron microscopy. Results: ${\beta}$-Elemene inhibited the viability of 786-0 cells in a dose- and time-dependent manner. The anti-tumor effect was associated with induction of apoptosis. Further study showed that ${\beta}$-elemene inhibited the MAPK/ERK as well as PI3K/Akt/mTOR signalling pathways. Moreover, robust autophagy was observed in cells treated with ${\beta}$-elemene. Combined treatment of ${\beta}$-elemene with autophagy inhibitors 3-methyladenine or chlorochine significantly enhanced the anti-tumor effects. Conclusions: Our data provide first evidence that ${\beta}$-elemene can inhibit the proliferation of RCC 786-0 cells by inducing apoptosis as well as protective autophagy. The anti-tumor effect was associated with the inhibition of MAPK/ERK and PI3K/Akt/mTOR signalling pathway. Inhibition of autophagy might be a useful way to enhance the anti-tumor effect of ${\beta}$-elemene on 786-0 cells.

Adjuvant Radiotherapy after Breast Conserving Treatment for Breast Cancer:A Dosimetric Comparison between Volumetric Modulated Arc Therapy and Intensity Modulated Radiotherapy

Liu, Zhe-Ming,Ge, Xiao-Lin,Chen, Jia-Yan,Wang, Pei-Pei,Zhang, Chi,Yang, Xi,Zhu, Hong-Cheng,Liu, Jia,Qin, Qin,Xu, Li-Ping,Lu, Jing,Zhan, Liang-Liang,Cheng, Hong-Yan,Sun, Xin-Chen Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.8

Background: Radiotherapy is an important treatment of choice for breast cancer patients after breast-conserving surgery, and we compare the feasibility of using dual arc volumetric modulated arc therapy (VMAT2), single arc volumetric modulated arc therapy (VMAT1) and Multi-beam Intensity Modulated Radiotherapy (M-IMRT) on patients after breast-conserving surgery. Materials and Methods: Thirty patients with breast cancer (half right-sided and half left-sided) treated by conservative lumpectomy and requiring whole breast radiotherapy with tumor bed boost were planned with three different radiotherapy techniques: 1) VMAT1; 2) VMAT2; 3) M-IMRT. The distributions for the planning target volume (PTV) and organs at risk (OARs) were compared. Dosimetries for all the techniques were compared. Results: All three techniques satisfied the dose constraint well. VMAT2 showed no obvious difference in the homogeneity index (HI) and conformity index (CI) of the PTV with respect to M-IMRT and VMAT1. VMAT2 clearly improved the treatment efficiency and can also decrease the mean dose and V5Gy of the contralateral lung. The mean dose and maximum dose of the spinal cord and contralateral breast were lower for VMAT2 than the other two techniques. The very low dose distribution (V1Gy) of the contralateral breast also showed great reduction in VMAT2 compared with the other two techniques. For the ipsilateral lung of right-sided breast cancer, the mean dose was decreased significantly in VMAT2 compared with VMAT1 and M-IMRT. The V20Gy and V30Gy of the ipsilateral lung of the left-sided breast cancer for VMAT2 showed obvious reduction compared with the other two techniques. The heart statistics of VMAT2 also decreased considerably compared to VMAT1 and M-IMRT. Conclusions: Compared to the other two techniques, the dual arc volumetric modulated arc therapy technique reduced radiation dose exposure to the organs at risk and maintained a reasonable target dose distribution.