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101.
目的探究昼夜节律基因对红花黄酮类物质生物合成的影响及机制。方法基于红花花冠转录组及代谢组数据库筛选潜在调控红花黄酮类化合物生物合成的昼夜节律基因;用qPCR测定红花各部位以及花冠单日不同时间点昼夜节律基因的表达量,液质联用测定黄酮类化合物的积累量,并分析二者的相关性;酵母双杂交实验验证昼夜节律基因的互作蛋白。结果获得7个昼夜节律基因PRR1、PRR2、ELF3、FT、PHYB、GI、ZTL,其中PRR1基因与黄酮类化合物积累量呈正相关(r≥0.7)。PRR1全长3201 bp,编码421个氨基酸,与水稻OsPRR73基因高度同源,将其命名为CtPRR1(GenBank登录号:MW492035)。CtPRR1主要在花中表达,表达量在日间逐渐升高,晚间逐渐下降;黄酮类化合物芹菜素、槲皮素、HSYA、山奈酚、Carthamin、山奈酚-3-O-葡萄糖苷以及野黄芩素的含量为白天逐渐降低,晚间逐渐升高,二者都有昼夜节律性且呈负相关(r≥?0.7)。酵母双杂实验得到2个热休克蛋白、3个AP2转录因子。结论CtPRR1对红花黄酮类成分的昼夜节律性积累起负调节作用;CtPRR1可能受这些互作蛋白的影响调控红花黄酮类成分的昼夜节律性积累。 相似文献
102.
目的:探讨左乙拉西坦与苯巴比妥的药物相互作用及作用机制。方法:临床药师通过神经内科ICU的一例伴难以控制、反复发作癫的急性重症脑炎病例用药发现问题,查阅病历资料及相关文献进行分析。结果:左乙拉西坦可引起苯巴比妥血药浓度降低,可能与两者竞争结合P糖蛋白有关。结论:临床药师应该加强对左乙拉西坦的药物相互作用的观察和研究,以促进抗癫药物的合理应用。 相似文献
103.
Jie Tian Xiao-Long Wang Long-Cheng Wang Fei Chen Yun Tian Li Ma Chao-Yun Pan Yan-Ping Wang 《Pharmaceutical biology》2022,60(1):1331
ContextQiangli Wuhu (QLWH) mixture is a concoction approved and registered by Ningxia Medical Products Administration. It has therapeutic effects on various types of pneumonia.ObjectiveTo clarify the mechanisms of QLWH in treating pneumonia.Materials and methodsThe potential targets of QLWH in the treatment of pneumonia were predicted by network pharmacology. Male, Institute of Cancer Research (ICR) mice were randomly divided into five groups of 12 mice, control, vehicle, QLWH (10 and 20 mg/kg) and dexamethasone (DXM), and orally treated twice daily with normal saline, QLWH or DXM. The pneumonia model was established by tracheal instillation of lipopolysaccharide (LPS). After treatment five days, ELISA, H&E staining and Western blot were used to investigate protective effects of QLWH.ResultsNine hundred and ninety-four active ingredients were found through network pharmacology, corresponding to 135 targets for the treatment of pneumonia; compared to the vehicle group, QLWH (10 and 20 mg/kg) significantly decreased the levels of TNF-α (14.3% and 28.8%), IL-1β (23.9% and 42.8%) and IL-6 (13.2% and 16.1%), increased the levels of IL-10 (134.3% and 172.9%); in terms of mechanism, QLWH down-regulated TLR4/NF-κB/NLRP3 axis related proteins in lung tissue of pneumonia model mice (p < 0.05).Discussion and conclusionsThis study combined network pharmacology and animal experiments, providing effective evidence for the clinical promotion of QLWH. Meanwhile, it is of significance for further development. 相似文献
104.
目的 通过分析脊椎动物血红蛋白(Hb)分子进化过程,解释Hb相互作用的现象并推测作用机制.方法 采用NCBI、PDB等在线生物信息学网站及SMS、ANTHEPROT 5.0、Clustalx 2.0、MEGA 4、Vector NTI 9等软件包对比脊椎动物门各纲羊膜和非羊膜动物Hb氨基酸多序列的同源相似性,查找保守位点,构建分子进化树,预测二级结构,对比三级结构模型,推测Hb相互作用现象的发生机制.结果 氨基酸多序列对比显示,非羊膜动物α链没有保守氨基酸(cAA),β链有3个cAA,羊膜动物α链、β链分别有27个和68个cAA;分子进化树显示非羊膜动物Hb氨基酸每位点替代值(SpS)远大于羊膜动物(P<0.01);预测二级结构分析Hb作用面发现非羊膜动物α链40位氨基酸主要参与无规则卷曲结构,羊膜动物α链40位和β链94位氨基酸均主要参与α螺旋结构;对比空间结构模型发现羊膜动物α链均有一个苏氨酸(41位)与β链的组氨酸(98位)形成氢键,而非羊膜动物不能形成此氢键.结论 脊椎动物Hb相互作用发生的关键可能在于是否存在α链苏氨酸(41位)与β链组氨酸(98位) 形成的氢键. 相似文献
105.
D. N. Bateman 《European journal of clinical pharmacology》1986,30(2):205-208
Summary The effects of the benzamide cisapride (C) (8 mg) i.v. have been compared to placebo (P) in a double blind randomised study. The effects on gastric emptying, the absorption and effects of oral diazepam, and BP and pulse were observed.Cisapride increased the rate of gastric emptying of 500 ml liquid containing diazepam 10 mg (t1/2 C: 7.4 min, P: 14.9 min). The initial rate of absorption of diazepam contained in the drink was increased by C (AUC 0–1 h C: 328 µg h 1–1, P: 253 µg h 1–1, but there was no change in overall bioavailability. This change in diazepam kinetics was associated with a significantly greater impairment in reaction time in the first 45 min after drinking but not in self rated sedation. Cisapride produced a significant tachycardia (e.g. after 10 min C: 82 beats/min, P: 69 beats/min) which probably reflects a peripheral vasodilator action. Cisapride may therefore alter the pharmacokinetics and dynamics of concurrently administered drugs. 相似文献
106.
107.
Yang Li Lingling Huang Chengcheng Tang Enbo Zhang Lei Ding 《Journal of microencapsulation》2016,33(5):427-437
Potential use of liposome for polycationic colistin is hindered by their phospholipid membrane permeability. In this study, liposomes were modified with sodium cholesteryl sulphate (Chol-SO4?) for improving the colistin loading by enhancing the colistin-bilayer electrostatic attraction. We have evaluated two liposomes: colistin-entrapped liposome of Chol-SO4? (CCL) and coated Chol-SO4?/colistin complex liposome (CCCL). In comparison with CCL which formed large aggregates at Chol-SO4?/colistin charge ratio below 2:1, CCCL showed a smaller size less dependent on the charge ratio, probably arising from more colistin entrapped on the inner leaflet of bilayer. Both liposomes exhibited significantly increased entrapment efficiency as compared with the liposome without Chol-SO4?. But colistin released upon dilution, implying free transfer of colistin through bilayers. Pharmacokinetics results showed the approximately four-fold increase in the plasma AUC0–8?h for CCCL and CCL as compared with colistin solution, showing potential benefit for infectious target localisation by prolonging the systemic circulation of colistin. 相似文献
108.
《Drug discovery today》2022,27(5):1350-1366
The screening of compound–protein interactions (CPIs) is one of the most crucial steps in finding hit and lead compounds. Deep learning (DL) methods for CPI prediction can address intrinsic limitations of traditional HTS and virtual screening with the advantage of low cost and high efficiency. This review provides a comprehensive survey of DL-based CPI prediction. It first summarizes popular databases of small-molecule compounds, proteins and binding complexes. Then, it outlines classical representations of compounds and proteins in turn. After that, this review briefly introduces state-of-the-art DL-based models in terms of design paradigms and investigates their prediction performance. Finally, it indicates current challenges and trends toward better CPI prediction and sketches out crucial approaches toward practical applications. 相似文献
109.
110.
van Roekel E Goossens L Scholte RH Engels RC Verhagen M 《Journal of child psychology and psychiatry, and allied disciplines》2011,52(10):1044-1051
Background: Loneliness is a common problem in adolescence. Earlier research focused on genes within the serotonin and oxytocin systems, but no studies have examined the role of dopamine‐related genes in loneliness. In the present study, we focused on the dopamine D2 receptor gene (DRD2). Methods: Associations among the DRD2, sex, parental support, and loneliness were examined in a longitudinal study spanning five annual waves (N = 307). Results: Using Latent Growth Curve Modeling, DRD2 genotype was not directly related to loneliness. Interactions were found between parental support and DRD2 genotype, showing that adolescents with the A2A2 genotype who perceived little support from their parents had the highest baseline levels of loneliness. Adolescents with an A1 allele were not susceptible to the rewarding effect of parental support. Conclusions: The present study is the first to examine the role of the DRD2 genotype in loneliness. Our results contribute to a further understanding of the environmental and genetic basis of loneliness in adolescence. 相似文献