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191.
192.
Jian Liu Yu Wen Lina Gao Liang Gao Fengjun He Jingxian Zhou 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):72-84
Abstract Fibroblast growth-factor receptor (FGFR) is a potential target for cancer therapy. We designed three novel series of FGFR1 inhibitors bearing indazole, benzothiazole, and 1H-1,2,4-triazole scaffold via fragment-based virtual screening. All the newly synthesised compounds were evaluated in vitro for their inhibitory activities against FGFR1. Compound 9d bearing an indazole scaffold was first identified as a hit compound, with excellent kinase inhibitory activity (IC50 = 15.0?nM) and modest anti-proliferative activity (IC50 = 785.8?nM). Through two rounds of optimisation, the indazole derivative 9?u stood out as the most potent FGFR1 inhibitors with the best enzyme inhibitory activity (IC50 = 3.3?nM) and cellular activity (IC50 = 468.2?nM). Moreover, 9?u also exhibited good kinase selectivity. In addition, molecular docking study was performed to investigate the binding mode between target compounds and FGFR1. 相似文献
193.
A novel spectrofluorometric method for the determination of furosemide (FUR) is described. The method is based on enhancement of fluorescence emission of FUR in the presence of zinc (II) complexes of 1,4‐bis(imidazol‐1‐ylmethyl)benzene. Under optimum conditions, the enhanced fluorescence intensity is linearly related to the concentration of FUR. The proposed method has been successfully applied to the determination of FUR in pharmaceutical preparations. The possible mechanism of this reaction is discussed briefly based on data from fluorescence spectroscopy, UV–vis absorption and infrared spectroscopy. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
194.
Jian Su Kittisak Sripanidkulchai Ying Hu Rungsiri Chaiittianan Bungorn Sripanidkulchai 《AAPS PharmSciTech》2013,14(3):1055-1062
Curcuma comosa has long been used as a gynecological medicine. Several diarylheptanoids have been purified from this plant, and their pharmacological effects were proven. However, there is no information about the absorption of C. comosa components to support the formulation usage. In the present study, C. comosa hexane extract and the mixture of its two major compounds, (4E,6E)-1,7-diphenylhepta-4,6-dien-3-ol (DA1) and (6E)-1,7-diphenylhept-6-en-3-ol (DA2), were formulated into nanoemulsions. The physical properties of the nanoemulsions and the in situ intestinal absorptions of DA1 and DA2 were evaluated. The results demonstrated the mean particle sizes at 0.207 ± 0.001 and 0.408 ± 0.014 μm, and the zeta potential at −14.57 ± 0.85 and −10.47 ± 0.32 mV for C. comosa nanoemulsion (C.c-Nano) and mixture of diarlylheptanoid nanoemulsions (DA-Nano), respectively. The entrapments of DA1 and DA2 were 76.61% and 75.41%, and 71.91% and 71.63% for C.c-Nano and DA-Nano, respectively. The drug loading ratios of DA1 and DA2 were 351.47 and 614.53 μg/mg, and 59.48 and 126.72 μg/mg for C.c-Nano and DA-Nano. The intestinal absorption rates of DA1 and DA2 were 0.329 ± 0.015 and 0.519 ± 0.026 μg/min/cm2 in C.c-Nano, and 0.380 ± 0.006 and 0.428 ± 0.036 μg/min/cm2 in DA-Nano, which were five to ten times faster than those in oil. In conclusion, the formulation in nanoemulsion forms obviously increased the intestinal absorption rate of diarylheptanoids.KEY WORDS: Curcuma comosa, diarylheptanoids, intestinal absorption, nanoemulsion, phytoestrogen 相似文献
195.
196.
Xianzhong Chen Huiying Fang Bin Zhuge Zhengxiang Wang Algasan Govender Jian Zhuge 《Process Biochemistry》2013,48(10):1469-1475
197.
Virtualization is widely used in cloud computing environments to efficiently manage resources, but it also raises several challenges. One of them is the fairness issue of resource allocation among virtual machines. Traditional virtualized resource allocation approaches distribute physical resources equally without taking into account the actual workload of each virtual machine and thus often leads to wasting. In this paper, we propose a virtualized resource auction and allocation model (VRAA) based on incentive and penalty to correct this wasting problem. In our approach, we use Nash equilibrium of cooperative games to fairly allocate resources among multiple virtual machines to maximize revenue of the system. To illustrate the effectiveness of the proposed approach, we then apply the basic laws of auction gaming to investigate how CPU allocation and contention can affect applications’ performance (i.e., response time), and its effect on CPU utilization. We find that in our VRAA model, the fairness index is high, and the resource allocation is closely proportional to the actual workloads of the virtual machines, so the wasting of resources is reduced. Experiment results show that our model is general, and can be applied to other virtualized non-CPU resources. 相似文献
198.
Jian Wan Jianliang Zhang Li Zhou Yicheng Wang Congfeng Jiang Yongjian Ren Jue Wang 《Cluster computing》2013,16(4):625-638
Taking advantage of distributed storage technology and virtualization technology, cloud storage systems provide virtual machine clients customizable storage service. They can be divided into two types: distributed file system and block level storage system. There are two disadvantages in existing block level storage system: Firstly, Some of them are tightly coupled with their cloud computing environments. As a result, it’s hard to extend them to support other cloud computing platforms; Secondly, The bottleneck of volume server seriously affects the performance and reliability of the whole system. In this paper we present a lightweighted block-level storage system for clouds—ORTHRUS, based on virtualization technology. We first design the architecture with multiple volume servers and its workflows, which can improve system performance and avoid the problem. Secondly, we propose a Listen-Detect-Switch mechanism for ORTHRUS to deal with contingent volume servers’ failure. At last we design a strategy that dynamically balances load between multiple volume servers. We characterize machine capability and load quantity with black box model, and implement the dynamic load balance strategy which is based on genetic algorithm. Extensive experimental results show that the aggregated I/O throughputs of ORTHRUS are significantly improved (approximately two times of that in Orthrus), and both I/O throughputs and IOPS are also remarkably improved (about 1.8 and 1.2 times, respectively) by our dynamic load balance strategy. 相似文献
199.
Haixiang Wei Gan Shen Xiaolong Deng Dong Lou Binbin Sun Hao Wu Long Long Tao Ding Jian Zhao 《Cell and tissue banking》2013,14(4):699-706
Rheumatoid arthritis (RA) is the most common degenerative arthritic cartilage and represents a disease where the prospect of stem cell therapy offers considerable hope. Currently, bone marrow (BM) represents the major source of mesenchymal stem cells (MSCs) for cell therapy. In the pathology of RA, the pro-inflammatory cytokines, such as interleukin 6 (IL-6) play a pivotal role. To investigate the direct role of IL-6 in the chondrogenic differentiation of murine MSCs (mMSCs), we isolate MSCs from the murine bone marrow, and induce MSCs chondrogenesis with different concentrations of IL-6 in vitro. Through detecting the histological and histochemical qualities of the aggregates, we demonstrate that IL-6 inhibited the differentiation of MSCs into chondrocytes in the dose-dependence manner. These findings suggest that possible strategies for improving the clinical outcome of cartilage repair procedures. 相似文献
200.
Yanhong Zhao Peng Chen Xiaofang Liao Bujin Zhou Jian Liao Zhipeng Huang Xiangjun Kong Ruiyang Zhou 《Molecular breeding : new strategies in plant improvement》2013,32(4):969-976
mtDNA was isolated from cytoplasmic male sterility (CMS) line P3A and its maintainer P3B of kenaf (Hibiscus cannabinus L.). The atp9 gene and its two flanking sequences were obtained using homology cloning and high-efficiency thermal asymmetric interlaced PCR methods. The coding sequences showed only two base pairs difference between the CMS and its maintainer, and shared a homology of over 87 % with atp9 genes from other species in GenBank. However, when comparing the flanking sequences, a 47-bp deletion was characterized at the 3′ flanking sequence of atp9 in the CMS line. Quantitative PCR analysis indicated that the expression level of atp9 in the CMS line was 0.937-fold that of its maintainer. Furthermore, the respiratory rate of anthers in the CMS line was markedly lower than that of its maintainer. The results indicated that the 47-bp deletion at the 3′ flanking sequence of atp9 and/or down-regulated expression of the atp9 gene in the CMS line might be closely related to CMS in kenaf. To confirm whether the 47-bp deletion was specific to cytoplasm of male sterile lines, another 21 varieties were used for further analysis. The results showed that the 47-bp deletion was specific to male sterile cytoplasm (MSC) of kenaf. Based on these, a specific molecular marker was developed to distinguish the MSC from male fertile cytoplasm of kenaf. 相似文献