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1.
目的 研究云南萝芙木Rauvolfia yunnanensis根中的吲哚类生物碱化学成分及抗菌活性,明确该植物抗菌活性成分。方法 采用硅胶柱色谱、RP-C18、Sephadex LH-20、半制备HPLC等方法进行分离纯化,结合波谱数据及文献参数对化合物进行结构鉴定,并采用微量肉汤稀释法对单体化合物进行抗菌活性评价。结果 从云南萝芙木根醋酸乙酯部位共分离得到20个吲哚类生物碱化合物,分别鉴定为维诺任碱(1)、霹雳萝芙木碱(2)、四叶萝芙木新碱(3)、萝加灵(4)、西特斯日钦碱(5)、缝籽木醇(6)、柯楠醇(7)、二氢柯楠醇(8)、毛茶碱(9)、异毛茶碱(10)、佩立任碱(11)、10-羟基-16-表-花菊醇(12)、育亨宾(13)、降马枯星碱B(14)、洛柯碱(15)、阿枯米定碱(16)、去乙酰阿枯米灵(17)、利血平(18)、哈尔满碱(19)、梅林诺宁F(20)。其中化合物20对白色念球菌表现出较好的抗菌活性,最低抑菌浓度(minimum inhibitory concentration,MIC)值为3.12μg/mL,与临床抗真菌药物氟康唑的MIC值相同。化合物111对大肠杆菌,化合物111320对枯草芽孢杆菌均表现出一定的抗菌活性,MIC值为6.25~12.50 μg/mL,活性与植物源抗菌药物小檗碱相当。结论 化合物20为首次从萝芙木属中分离得到,化合物68131618均为首次从该植物中分离得到,部分单体化合物表现出潜在抗菌活性。  相似文献   
2.
潘赐明  任雪  韦姗姗  曹蓓苓  王维  杨艳  陈文慧  徐宏喜 《中草药》2023,54(12):3911-3920
目的 基于中医药整合药理学和转录组学探究丹栀逍遥散防治焦虑肝郁化火证的作用机制。方法 采用中医药整合药理学研究平台v2.0,检索并获取丹栀逍遥散的活性成分及靶标、焦虑肝郁化火证靶标信息,构建中药-成分-靶点-通路网络。将交集基因导入String数据库,构建交集靶点的蛋白互作网络,以确定最终需要验证的靶标。利用GEO数据库转录组学验证整合网络药理学结果,同时采用动物实验进行验证。结果 共筛选出与焦虑肝郁化火证相关的靶标13个,丹栀逍遥散活性成分430种。整合药理学结果显示,丹栀逍遥散防治焦虑肝郁化火证主要通过调控α-氨基-3-羟基-5-甲基-4-异噁唑丙酸受体(α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid receptor,AMPAR)、蛋白激酶A(protein kinase A,PKA)、N-甲基-D-天冬氨酸(N-methyl-D-aspartic acid,NMDA)受体的激活及磷脂酰肌醇3-激酶(phosphatidylinositide 3-kinases,PI3K)/蛋白激酶B(protein kinase B,...  相似文献   
3.
张莹莹  张萱  李文春  陈绍田  陈佳 《中草药》2023,54(14):4420-4426
目的 研究姜黄Curcuma longa根部的化学成分。方法 采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱和HPLC等色谱技术进行分离纯化,通过理化性质与波谱数据分析鉴定结构。结果 从姜黄根部热水提取部位中分离得到10个化合物,分别鉴定为姜黄酮G(1)、姜黄酮H(2)、11-羟基-红没药-1,3(15),9-三烯(3)、香草醇(4)、甜没药姜黄醇(5)、甜没药姜黄醇B(6)、intermedin B(7)、longpene C(8)、3-(4-羟基-3-甲氧基苯基)丙烷-1,2-二醇(9)、(±)-松脂醇(10)。结论 化合物13为新化合物,其中化合物12互为差向异构体;化合物910为首次从姜黄中分离得到。  相似文献   
4.
Current knowledge on the effects of nut consumption on human health has rapidly increased in recent years and it now appears that nuts may play a role in the prevention of chronic age-related diseases. Frequent nut consumption has been associated with better metabolic status, decreased body weight as well as lower body weight gain over time and thus reduce the risk of obesity. The effect of nuts on glucose metabolism, blood lipids, and blood pressure is still controversial. However, significant decreased cardiovascular risk has been reported in a number of observational and clinical intervention studies. Thus, findings from cohort studies show that increased nut consumption is associated with a reduced risk of cardiovascular disease and mortality (especially that due to cardiovascular-related causes). Similarly, nut consumption has been also associated with reduced risk of certain cancers, such as colorectal, endometrial, and pancreatic neoplasms. Evidence regarding nut consumption and neurological or psychiatric disorders is scarce, but a number of studies suggest significant protective effects against depression, mild cognitive disorders and Alzheimer’s disease. The underlying mechanisms appear to include antioxidant and anti-inflammatory actions, particularly related to their mono- and polyunsaturated fatty acids (MUFA and PUFA, as well as vitamin and polyphenol content). MUFA have been demonstrated to improve pancreatic beta-cell function and regulation of postprandial glycemia and insulin sensitivity. PUFA may act on the central nervous system protecting neuronal and cell-signaling function and maintenance. The fiber and mineral content of nuts may also confer health benefits. Nuts therefore show promise as useful adjuvants to prevent, delay or ameliorate a number of chronic conditions in older people. Their association with decreased mortality suggests a potential in reducing disease burden, including cardiovascular disease, cancer, and cognitive impairments.  相似文献   
5.
BackgroundThe overexpression of CXCR4, C-Met and VEGF-C present widely in breast tumors, they may be markers of resistance to treatment. However, the studies are still controversial. Thus, this meta-analysis aims to research the relationship between the overexpression of CXCR4, C-Met, VEGF-C and clinical prognosis among breast cancer patients.MethodsPubMed and EMBASE databases were searched for eligible literature. The outcomes of interest were progression-free survival (PFS), relapse-free survival (RFS) and overall survival (OS). All tests of statistical significance were two sided.ResultsA total of 7830 patients from 28 eligible studies were assessed. The overexpression of the CXCR4 and C-Met both implied significantly worse PFS compared with normal expression [HR = 2.56, 95% CI = 1.34–4.91, P = 0.005; and HR = 1.63 95% CI = 1.20–2.22, P = 0.002]. Meanwhile, if patients had high expression of CXCR4, they would have worse OS [HR = 2.56 95% CI = 1.52–4.31, P = 0.000]. However, the overexpression of C-Met did not relate to OS for breast cancer patients [HR = 1.16, 95% CI = 0.69–1.95, P = 0.570]. Meanwhile, no statistically significant different was observed with respect to PFS and OS between VEGF-C overexpression and normal expression [HR = 0.99, 95% CI = 0.64–1.52, P = 0.968; and HR = 0.76, 95% CI = 0.43–1.33, P = 0.333].ConclusionsOur meta-analysis showed that CXCR4 and C-Met were efficient prognostic factors for breast cancer. Nevertheless, highly expressing VEGF-C was not related to progression-free survival and overall survival. Due to the small samples and insufficient date, further studies should be conducted to clarify the association between the overexpression of CXCR4 or C-Met or VEGF-C and the prognosis about breast cancer patients.  相似文献   
6.
原发性肾小球源性血尿俗称肾性血尿,是指血尿来源于肾小球,临床上表现为单纯性血尿或血尿伴蛋白尿,多见于原发性肾小球疾病,如IgA肾病、系膜增生性肾炎、局灶性肾小球硬化症、肾囊肿、多囊肾等,并且排除狼疮性肾炎、紫癜性肾炎等继发性肾小球疾病等。在中医文献中无明确该病名的相关记载,根据本病的临床特点,主要将其归属“尿血”“溺血”“溲血”“血证”等范畴。何渝煦教授根据黄元御“溺血”理论,认为本病以水寒土湿、脾陷木郁为本,膀胱湿热、少阴虚火为标。故运用黄氏宁波汤加减辨治原发性肾小球源性血尿,以泻湿燥土、升木达郁为法。  相似文献   
7.
The interactions between trypsin and gallic acid (GA) were investigated by means of fluorescence spectroscopy, UV-vis absorption spectroscopy, resonance light scattering (RLS) spectroscopy, synchronous fluorescence spectroscopy, and enzymatic inhibition assay. It was found that GA can cause the fluorescence quenching of trypsin during the process of formation of GA-trypsin complex, resulting in inhibition of trypsin activity (IC50 = 3.9 × 10−6 mol/L). The fluorescence spectroscopic data showed that the quenching efficiency can reach about 80%. The binding constants were 1.9371 × 104 L/mol, 1.8192 × 104 L/mol, and 1.7465 × 104 L/mol at three temperatures, respectively. The thermodynamic parameters revealed that hydrogen bonds, van der Waals, hydrophobic, and electrostatic interactions were involved in the binding process of GA to trypsin. Molecular modeling studies illustrated a specific display of binding information and explained most of the experiment phenomena. The microenvironments of tryptophan and tyrosine residue in trypsin were changed by the GA. Results indicated that GA was a strong quencher and inhibitor of trypsin.  相似文献   
8.
曹冠华  张雪  顾雯  陈迪  和志伟  陈耔翰  俞捷  贺森 《中草药》2019,50(16):3930-3936
目的调查不同产地滇黄精根系中丛枝菌根真菌(AMF)和深色有隔内生真菌(DSE)定殖情况,并探讨其与主要功效成分之间的相关性。方法以产自于云南省5个样地的滇黄精为研究对象,采用碱解离-酸性品红染色法,调查AMF和DSE在滇黄精须根部位的定殖情况,并对典型形态结构进行拍照分析;采用硫酸苯酚法、香草醛-冰醋酸-高氯酸比色法、分光光度法和醇溶热浸法测定滇黄精根状茎中多糖、薯蓣皂苷元、总黄酮和浸出物含量,并通过皮尔森相关系数法分析AMF及其典型结构定殖率、DSE及其典型结构定殖率与4种功效成分含量之间的相关性。结果在5个样地中,AMF和DSE在滇黄精须根中的平均定殖率范围分别为26.25%~57.54%、31.67%~45.19%,其中样地红河州蒙自县(HHMZ)AMF和DSE定殖率均高于其他样地。4种功效成分与AMF、DSE定殖率及典型结构定殖率之间均呈正相关,其中多糖、薯蓣皂苷元和总黄酮含量与AMF、DSE定殖率相关性相对较高,AMF/DSE相关系数分别为0.838/0.887、0.819/0.703、0.785/0.855,且多糖含量与AMF菌丝定殖率、DSE定殖率呈显著相关。此外,AMF及典型结构定殖率与DSE及典型结构定殖率之间、4种功效成分含量两两之间均存有较高的相关性。结论 AMF和DSE在滇黄精须根中有着较高的定殖率,且与主要功效成分含量之间呈正相关。本研究为实施滇黄精生态种植、采用生物手段增产增收提供了数据支持和实验依据。  相似文献   
9.
金铁锁叶绿体基因组序列及其系统发育分析   总被引:1,自引:0,他引:1  
高亚芳  刘莹莹  杨从卫  李国栋  钱子刚 《中草药》2019,50(22):5532-5536
目的解析金铁锁叶绿体基因组结构和确定其在石竹科的系统位置。方法基于二代测序技术IlluminaHiseq平台,对金铁锁叶绿体基因组进行测序,使用生物信息学分析软件进行组装和注释,并以苋科植物千穗谷为外类群,通过RAxM L 8.2.11软件构建ML系统发育树,分析石竹科属间的亲缘关系。结果金铁锁叶绿体基因组总长为153977bp。LSC和SSC区被2个反向重复区域IRs隔开,其大小分别为84 385、17 526、26 033 bp。除去重复后,共编码109个基因,包含75个PCGs,30个tR NA和4个rR NA基因。总的CG含量为36.5%,IR区(42.4%)GC含量明显高于LSC(34.2%)和SSC(30.1%)区。在系统进化树中,金铁锁与长萼瞿麦互为姊妹类群,且各节点的支持率较高,能够清晰反映属间的亲缘关系。结论本研究对金铁锁叶绿体基因组结构进行了解析,并探讨了石竹科属间系统发育关系,为金铁锁种质资源综合评价、系统进化等研究提供有效的科学数据。  相似文献   
10.
陈彦伍  董发武  秦天丽  孙恒  宋俏  何红平 《中草药》2019,50(22):5621-5631
大叶山楝Aphanamixis grandifolia为楝科山楝属植物,具有舒筋活络、通痹及祛风除湿等功效。大叶山楝中含有柠檬苦素类衍生物、甘遂烷型三萜、达玛烷型三萜、环阿尔廷烷型三萜、二萜及倍半萜等萜类化合物,具有杀虫、抗肿瘤、抗炎、抗疟疾和抑菌等生物活性。对大叶山楝萜类化学成分及其生物活性研究进展进行综述,以期为该植物的研究和开发利用提供参考。  相似文献   
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