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51.
Background: The antineoplastic activity of Chelidonium majus has been reported, but its mechanism of action (MoA) is unsuspected. The emerging theory of systems pharmacology may be a useful approach to analyze the complicated MoA of this multi-ingredient traditional Chinese medicine (TCM). Methods: We collected the ingredients and related compound-target interactions of C. majus from several databases. The bSDTNBI (balanced substructure-drug-target network-based inference) method was applied to predict each ingredient’s targets. Pathway enrichment analysis was subsequently conducted to illustrate the potential MoA, and prognostic genes were identified to predict the certain types of cancers that C. majus might be beneficial in treatment. Bioassays and literature survey were used to validate the in silico results. Results: Systems pharmacology analysis demonstrated that C. majus exerted experimental or putative interactions with 18 cancer-associated pathways, and might specifically act on 13 types of cancers. Chelidonine, sanguinarine, chelerythrine, berberine, and coptisine, which are the predominant components of C. majus, may suppress the cancer genes by regulating cell cycle, inducing cell apoptosis and inhibiting proliferation. Conclusions: The antineoplastic MoA of C. majus was investigated by systems pharmacology approach. C. majus exhibited promising pharmacological effect against cancer, and may consequently be useful material in further drug development. The alkaloids are the key components in C. majus that exhibit anticancer activity.  相似文献   
52.
53.
Protein kinase CK2 - A key suppressor of apoptosis   总被引:1,自引:0,他引:1  
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54.
Desaturation of fatty acids is a key reaction in the biosynthesis of moth sex pheromones. The main component of Spodoptera littoralis sex pheromone blend is produced by the action of Δ11 and Δ9 desaturases. In this article, we report on the cloning of four desaturase-like genes in this species: one from the fat body (Sls-FL1) and three (Sls-FL2, Sls-FL3 and Sls-FL4) from the pheromone gland. By means of a computational/phylogenetic method, as well as functional assays, the desaturase gene products have been characterized. The fat body gene expressed a Δ9 desaturase that produced (Z)-9-hexadecenoic and (Z)-9-octadecenoic acids in a (1:4.5) ratio, whereas the pheromone gland Sls-FL2 expressed a Δ9 desaturase that produced (Z)-9-hexadecenoic and (Z)-9-octadecenoic acids in a (1.5:1) ratio. Although both Δ9 desaturases produced (Z)-9-tetradecenoic acid from myristic acid, transformed yeast grown in the presence of a mixture of myristic and (E)-11-tetradecenoic acids produced (Z,E)-9,11-tetradecadienoic acid, but not (Z)-9-tetradecenoic acid. The Sls-FL3 gene expressed a protein that produced a mixture of (E)-11-tetradecenoic, (Z)-11-tetradecenoic, (Z)-11-hexadecenoic and (Z)-11-octadecenoic acids in a 5:4:60:31 ratio. Despite having all the characteristics of a desaturase gene, no function could be found for Sls-FL4.  相似文献   
55.

Background

Improving the equitable distribution of government healthcare subsidies (GHS), particularly among low-income citizens, is a major goal of China’s healthcare sector reform in China.

Objectives

This study investigates the distribution of GHS in China between socioeconomic populations at two different points in time, examines the comparative distribution of healthcare benefits before and after healthcare reforms in Northwest China, compares the parity of distribution between urban and rural areas, and explores factors that influence equitable GHS distribution.

Methods

Benefit incidence analysis of GHS progressivity was performed, and concentration and Kakwani indices for outpatient, inpatient, and total healthcare were calculated. Two rounds of household surveys that used multistage stratified samples were conducted in 2003 (13,564 respondents) and 2008 (12,973 respondents). Data on socioeconomics, healthcare payments, and healthcare utilization were collected using household interviews.

Results

High-income individuals generally reap larger benefits from GHS, as reflected by positive concentration indices, which indicates a regressive system. Concentration indices for inpatient care were 0.2199 (95% confidence interval [CI], 0.0829 to 0.3568) and 0.4445 (95% CI, 0.3000 to 0.5890) in 2002 (urban vs. rural, respectively), and 0.3925 (95% CI, 0.2528 to 0.5322) and 0.4084 (95% CI, 0.2977 to 0.5190) in 2007. Outpatient healthcare subsidies showed different distribution patterns in urban and rural areas following the redesign of rural healthcare insurance programs (urban vs. rural: 0.1433 [95% CI, 0.0263 to 0.2603] and 0.3662 [95% CI, 0.2703 to 0.4622] in 2002, respectively; 0.3063 [95% CI, 0.1657 to 0.4469] and −0.0273 [95% CI, −0.1702 to 0.1156] in 2007).

Conclusions

Our study demonstrates an inequitable distribution of GHS in China from 2002 to 2007; however, the inequity was reduced, especially in rural outpatient services. Future healthcare reforms in China should not only focus on expanding the coverage, but also on improving the equity of distribution of healthcare benefits.  相似文献   
56.
Members of the AP1/SQUA subfamily of plant MADS-box genes play broad roles in the regulation of reproductive meristems, the specification of sepal and petal identities, and the development of leaves and fruits. It has been shown that AP1/SQUA-like genes are angiosperm-specific, and have experienced several major duplication events. However, the evolutionary history of this subfamily is still uncertain. Here, we report the isolation of 14 new AP1/SQUA-like genes from seven early-diverging eudicots and the identification of 11 previously uncharacterized ESTs and genomic sequences from public databases. Sequence comparisons of these and other published sequences reveal a conserved C-terminal region, the FUL motif, in addition to the known euAP1/paleoAP1 motif, in AP1/SQUA-like proteins. Phylogenetic analyses further suggest that there are three major lineages (euAP1, euFUL, and AGL79) in core eudicots, likely resulting from two close duplication events that predated the divergence of core eudicots. Among the three lineages, euFUL is structurally very similar to FUL-like genes from early-diverging eudicots and basal angiosperms, whereas euAP1 might have originally been generated through a 1-bp deletion in the exon 8 of an ancestral euFUL- or FUL-like gene. Because euFUL- and FUL-like genes usually have broad expression patterns, we speculate that AP1/SQUA-like genes initially had broad functions. Based on these observations, the evolutionary fates of duplicate genes and the contributions of the frameshift mutation and alternative splicing to functional diversity are discussed.  相似文献   
57.
In the past decades,many materials have been studied as carriers for targeted drug delivery.However,there is a need for utilizable and selective carrier materia...  相似文献   
58.
This article reported the synthesis and bioevaluation of two [18F] labeled benzimidazole derivatives, 4-(5-(2-[18F] fluoro-4-nitrobenzamido)-1-methyl-1H-benzimidazol-2-yl) butanoic acid ([18F] FNBMBBA, [18F]a1) and 3-(2-fluoroethyl)-7-methyl-2-propyl-3H-benzimidazole-5-carboxylic acid ([18F] FEMPBBA, [18F]b1) for PET tumor imaging. The preparation [18F] FEMPBBA was completed in 1 h with overall radiochemical yield of 50–60% (without decay corrected). Biodistribution assay in S180 tumor bearing mice of both compounds were carried out, and the results are both meaningful. [18F] FEMPBBA which can be taken as a revision of [18F] FNBMBBA got an excellent result, and has significant advantages in some aspects compared with L-[18F] FET and [18F]-FDG in the same animal model, especially in tumor/brain uptake ratio. The tumor/brain uptake ratio of [18F] FEMPBBA gets to 4.81, 7.15, and 9.8 at 30 min, 60 min and 120 min, and is much higher than that of L-[18F] FET (2.54, 2.92 and 2.95) and [18F]-FDG (0.61, 1.02, 1.33) at the same time point. The tumor/muscle and tumor/blood uptake ratio of [18F] FEMPBBA is also higher than that of L-[18F] FET at 30 min and 60 min. This result indicates compound [18F] FEMPBBA is a promising radiotracer for PET tumor imaging.  相似文献   
59.
拟南芥和琴叶拟南芥中MADS-box基因的比较进化分析   总被引:1,自引:0,他引:1  
MADS-box基因编码一类转录因子。在被子植物中,MADS-box基因对于营养生长和生殖发育都有重要的调控作用,是植物体(特别是花序、花和果实)的正常发育所不可或缺的。为了理解近缘物种在遗传基础上的异同,我们对拟南芥(Arabidopsis thaliana)和琴叶拟南芥(A.lyrata)基因组中MADS-box基因的拷贝数目和进化式样进行了比较分析。通过搜索公共数据库,我们在拟南芥和琴叶拟南芥中分别鉴定出了106和115个基因。系统发育分析的结果表明,这些基因属于I型和II型MADS-box基因。在两个物种分化之后,II型基因的拷贝数目变化不大,I型基因则经历了多次独立的基因丢失和获得事件。通过比较这些基因在染色体上的排列,我们不但鉴定出了存在微共线性的基因组区段,而且发现新基因产生的主要机制是串联重复和散在重复。分子进化的研究进一步表明,I型和II型基因在进化式样上存在着显著差异:II型基因在进化中一般都受到了较强的选择压力,而I型基因大多受到的选择压力较弱。本研究将为深入理解近缘物种在基因和基因组层面上的异同、探讨物种分化和生物多样性形成的机制等问题提供新思路。  相似文献   
60.
A rapid, sensitive and specific high performance liquid chromatography–tandem mass spectrometric (HPLC–MS/MS) method has been developed for quantification of mitoxantrone in rat plasma. The analyte and palmatine (internal standard) were extracted from plasma samples with diethyl ether–dichloromethane (3:2, v/v) and separated on a C18 column. The chromatographic separation was achieved within 2.5 min using methanol–10 mM ammonium acetate containing 0.1% acetic acid as the mobile phase at a flow rate of 0.2 mL/min. The method was linear over the range of 0.5–500 ng/mL. The lower limit of quantification (LLOQ) was 0.5 ng/mL. Finally, the method was successfully applied to a pharmacokinetic study of mitoxantrone in rats following intravenous administration.  相似文献   
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