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Xi Chen Fang Lu Ganggang Luo Yue Ren Jing Ma 《Journal of biomolecular structure & dynamics》2020,38(15):4461-4470
AbstractFarnesoid X receptor (FXR), a bile acid receptor, has important roles in maintaining bile acid and cholesterol homeostasis, which is an attractive target for hyperlipidemia. Present study aimed to discover potential selective FXR agonists over G-protein coupled bile acid receptor 1 (GPBAR1, TGR5) from traditional Chinese medicine (TCM) by using virtual screening, in vitro studies and molecular dynamics simulation (MD). Ligand-based pharmacophore model for FXR was firstly built to screen FXR agonists from the Traditional Chinese Medicine Database (TCMD). Then, 21 FXR crystal structures were clustered in two types and two representative structures (PDB ID: 3OMM and 3P89) were, respectively, used to carry out molecular docking to refine the screened result. Moreover, the pharmacophore model for GPBAR1 was built to screen selective FXR agonists with no activity on GPBAR1. A set of 24 candidate selective FXR agonists which fitvalue of FXR pharmacophore model and docking score of 3OMM and 3P89 were in the top 100 and cannot match the pharmacophore model for GPBAR1 were obtained. By the lipid-lowering activity test in HepG2 cell lines, Arctigenin was identified to be potential selective FXR agonist with the activity of 20?μmol·L?1. After down-regulating FXR, Arctigenin could increase the mRNA of FXR while exerted no effect on the mRNA of GPBAR1. MD was further used to interpret the mechanism of Arctigenin with the representative structures. This research provided a new screening procedure for finding selective candidate compounds and appropriate docking models of a target by considering the structure diversity of PDB structures, which was applied to discovery novel selective FXR agonists to treat hyperlipidemia.Communicated by Ramaswamy H. Sarma 相似文献
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Bérangère Farges Céline Laroche Jean‐François Cornet Claude‐Gilles Dussap 《Biotechnology progress》2009,25(1):151-162
The ability to cultivate the cyanobacterium Arhtrospira platensis in artificially lightened photobioreactors using high energetic efficiency (quasi‐monochromatic) red LED was investigated. To reach the same maximal productivities as with the polychromatic lightening control conditions (red + blue, P/2e? = 1.275), the need to work with an optimal range of wavelength around 620 nm was first established on batch and continuous cultures. The long‐term physiological and kinetic behavior was then verified in a continuous photobioreactor illuminated only with red (620 nm) LED, showing that the maximum productivities can be maintained over 30 residence times with only minor changes in the pigment content of the cells corresponding to a well‐known adaptation mechanism of the photosystems, but without any effect on growth and stoichiometry. For both poly and monochromatic incident light inputs, a predictive spectral knowledge model was proposed and validated for the first time, allowing the calculation of the kinetics and stoichiometry observed in any photobioreactor cultivating A. platensis, or other cyanobacteria if the parameters were updated. It is shown that the photon flux (with a specified wavelength) must be used instead of light energy flux as a relevant control variable for the growth. The experimental and theoretical results obtained in this study demonstrate that it is possible to save the energy consumed by the lightening device of photobioreactors using red LED, the spectral range of which is defined according to the action spectrum of photosynthesis. This appears to be crucial information for applications in which the energy must be rationalized, as it is the case for life support systems in closed environments like a permanent spatial base or a submarine. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 相似文献
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传统大豆发酵食品中大豆异黄酮的生理保健机能的研究进展 总被引:1,自引:0,他引:1
大豆异黄酮属于黄酮类化合物,是一类具有重要生物活性的化合物,在大豆和传统大豆发酵食品中含量丰富。近年来研究发现大豆异黄酮在预防癌症、骨质疏松症、心血管疾病和改善妇女更年期综合症等方面具有广泛的生理活性,因此引起了国内外学者的广泛关注。大豆异黄酮的研究,不仅为功能性大豆制品的开发提供理论基础,也为人们合理的膳食提供参考。综述近年来国内外对大豆异黄酮生理保健机能的研究进展。 相似文献
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Traditional concealed information paradigms rely on the idea that stimuli that are meaningful to a person (critical items)
will draw attentional resources disproportionately, relative to stimuli that are not (irrelevant items), generating detectable
differences on a suitable dependent variable (behavioral, psychophysiological, or neural). Here, we introduce a behavioral
paradigm that could be used to reveal concealed information by exploiting the link between concealed information and attentional
processes more directly. This novel paradigm is based on the attentional blink phenomenon in which detection of a stimulus
reduces detection accuracy rates of subsequent target stimuli within a 200–500 ms time window. We hypothesized that a well-known
face used as a critical item could capture attentional resources automatically, making it harder to detect the occurrence
of a subsequently presented target face. The results confirmed this hypothesis, and showed that concealed knowledge of a famous
face could be detected in 9 out of 12 individuals by looking for a relative dip in target detection accuracy after the presentation
of a critical item. 相似文献
46.
Aidi injection (ADI), a traditional Chinese biomedical preparation, is a promising adjuvant therapy for gynecologic tumors (GTs), including cervical cancer (CC), endometrial cancer (EC), and ovarian cancer (OC). Although studies have reported positively on ADI therapy, its exact effects and safety in GT patients remain controversial. Therefore, a wide-ranging systematic search of electronic databases was performed for this meta-analysis. Data from 38 trials including 3309 GT patients were analyzed. The results indicated that the combination of conventional treatment and ADI markedly improved the patients’ overall response rate (P<0.00001), disease control rate (P<0.00001), and quality of life (P<0.05) compared with conventional treatment alone. Furthermore, patient immunity was enhanced with combined treatment, as indicated by significantly increased percentages of CD3+ (P=0.005) and CD4+ (P<0.00001) and increased CD4+/CD8+ ratio (P=0.001). Most of the adverse events caused by radiochemotherapy such as gastrointestinal issues, leukopenia, thrombocytopenia, and hepatotoxicity, (P<0.05 for all) were significantly alleviated when ADI was used in the GT patients. However, other adverse events such as nephrotoxicity, diarrhea, alopecia, and neurotoxicity did not significantly differ between the two groups. Overall, these results suggest that the combination of conventional and ADI treatment is more effective than conventional treatment alone. 相似文献
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目的探讨四黄散外敷治疗竹叶青蛇咬伤肿胀的临床疗效。方法选择2017年10月~2020年4月我院收治的112例竹叶青蛇咬伤肿胀患者为研究对象,采用随机数字表法将患者分为观察组和对照组,每组56例。对照组采用常规蛇咬伤处理方案,包括清创、引流、注射抗蛇毒血清及对症治疗等。观察组在对照组治疗基础上采用四黄散外敷治疗。观察比较两组患者的有效止痛时间、肿胀开始消退时间、肿胀完全消退时间,并对两组患者治疗7d时的临床疗效进行比较。结果观察组在有效止痛时间、肿胀开始消退时间、肿胀完全消退时间方面均显著低于对照组,两组比较差异具有统计学意义(均P<0.05)。两组治疗后的总体疗效比较,观察组的治愈率为89.3%(50/56),对照组的治愈率为69.6%(39/56),两组比较差异有统计学意义(P<0.05)。结论四黄散外敷治疗竹叶青蛇咬伤肿胀的疗效确切,能有效减轻患者的疼痛感,促进肿胀消退,减轻炎症反应,值得临床应用。 相似文献
50.
综合认识大尺度的宏观生态系统结构功能、空间变异和动态演变的过程机理和模式机制,实现对生态系统变化及其对人类福祉影响的定量模拟、科学评估和预测预警,服务生态系统的利用保护及调控管理,是当代宏观生态系统科学的重要发展方向,正在孕育并形成大尺度的宏观生态系统科学整合生态学(IEMES)研究新领域。本研究通过对宏观生态系统科学整合生态学研究的基础理论、多学科知识融合途径及其关键技术问题的系统分析,形成以下几个基本认识: 1)宏观生态系统科学整合生态学研究是以区域、大陆和全球尺度的宏观生态系统为研究对象,采用多学科知识融合方法和技术,致力于解决人类社会发展的食物安全、资源安全、生态安全、环境安全等重大资源环境问题。2)宏观生态系统科学整合生态学研究的基本科技任务是: 理解宏观生态系统的结构功能基本属性,监测生态系统状态变化,解释生态系统时空演变规律,认知生态系统运维过程机理,定量评估生态系统功能状态及服务能力,预测生态系统动态演变及地理格局,预警生态系统变化及生态环境灾害。3)宏观生态系统科学整合生态学研究需要重新构造“多源数据分析-多模型模拟-多学科知识融合”的理论和方法学体系,发展“多尺度观测、多方法印证、多过程融合、跨尺度模拟”的多学科知识融合关键技术。4)大陆尺度的地基-空基-天基多时空尺度生态系统观测试验网络是承载多学科知识深度融合研究的基础科技设施,需要围绕区域、大陆和全球尺度的宏观生态系统科学问题,发展多要素-多过程-多界面-多介质-多尺度-多方法的多学科维度生态学知识融合关键技术。 相似文献