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1.
Cheng-Shi Jiang Yan-Qiong Guo Sheng Yin 《Journal of Asian natural products research》2019,21(4):377-383
Chromatographic fractionation of the EtOH extracts of the Traditional Chinese Medicine (TCM) Chloranthus japonicus, has led to the isolation of a new lindenane-type sesquiterpenoid lactone derivative (1). Rosmarylchloranthalactone E (1), which consists of lindenane sesquiterpenoid lactone and rosmarinic acid moieties linked via an ester bridge, was structurally elucidated by 1D and 2D NMR and HRMS data. Compound 1 was a potent phosphodiesterase-4 (PDE4) inhibitor with an IC50 value of 0.96 ± 0.04 μM. 相似文献
2.
Leonurus japonicus Houtt, a Chinese traditional herbal medicine, has been widely used to cure gynecological diseases, such as incomplete abortion and menoxenia. Leonurine, a major active alkaloid compound only be found in Leonurus japonicus Houtt, has been successfully extracted and purified. Recent evidence has shown that leonurine can regulate a variety of pathologic processes including oxidative stress, inflammation, fibrosis, apoptosis, and multiple metabolic disorders. Here, we have reviewed the pharmacological actions and biological functions of leonurine, with a focus on the role of leonurine in the amelioration of various pathological processes. Insights into the related signaling pathways and molecular mechanisms have strengthened our understanding on the function of leonurine in the alleviation of multiple pathological states. Our summary of the existing researches should help direct future research into the basic science and clinical applications in related diseases. 相似文献
3.
Min-Hong Jiang Yue Hu Lin Jiao Pan Dong Sheng Yin Zhi-Min Zhao 《Journal of Asian natural products research》2019,21(7):627-632
Five fractions prepared from the crude extract of Leonurus japonicus were examined in order to determine their cytotoxic potential. Under the bioassay guidance, a new labdane-type diterpenoid (1), and nine known ones (2–10) along with a seco-labdane (11) were isolated from the aerial parts of Leonurus japonicus. The structure elucidation was primarily based on comprehensive spectroscopic analyses, including HRESIMS, IR, and 1D and 2D NMR methods. Compound 4 (6β-hydroxy-15,16-epoxylabda-8,13(16),14-trien-7-one) exhibited potential cytotoxicity against HeLa cell line (IC50 = 23.75 μM). 相似文献
4.
目的 建立大鼠血浆中低聚仿刺参糖胺聚糖(DAHG-1W)的LC-MS/MS测定方法,研究大鼠单次静脉注射DAHG-1W后的血浆药物动力学。方法 大鼠血浆样品经灰色链霉菌蛋白酶预处理、温和酸水解脱除岩藻糖支链、硫酸软骨素ABC酶降解成主链二糖并用2-氨基吖啶酮衍生后,进行液相色谱-质谱联用(LC-MS/MS)分析。色谱分离采用Cortecs UPLC T3色谱柱(2.1mm×150 mm, 1.6 μm),流动相为10 mM乙酸铵水溶液-甲醇,梯度洗脱。质谱检测采用加热电喷雾离子源(H-ESI),以负离子方式检测,AMAC标记的CS-4S6S和CS-2S4S(内标)的多反应监测(MRM)离子对均为m/z 732.0→652.4,保留时间分别为9.0和7.4 min。应用上述LC-MS/MS方法测定大鼠尾静脉注射DAHG-1W(5 mg·kg-1)后的血浆药物浓度,采用WinNonLin 6.0版软件计算药代动力学参数。结果 大鼠血浆中DAHG-1W在3.91-125.00 μg·mL-1浓度范围内线性关系良好;日内和日间精密度均小于15%,准确度为102.60%-111.17%;回收率为89.16%-103.35%;无明显基质效应且血浆样品稳定性好。大鼠静脉注射给药后DAHG-1W的血药峰浓度(Cmax)为(36.73±2.10)μg·mL-1,半衰期(t1/2)为(277.31±56.22)min,清除率(Cl)为(0.82±0.09)mL·min-1·kg-1,0-300 min药时曲线下面积(AUC0-t)为(3638.30±45.84)min·μg·mL-1。结论 本研究建立了大鼠血浆中DAHG-1W的LC-MS/MS分析方法,可应用于DAHG-1W在大鼠体内的药物动力学研究。 相似文献
5.
目的:对金粟兰属植物银线草Chloranthus japonicus Sieb.全草的化学成分进行研究,以探究其药理活性物质基础。方法:采用硅胶、凝胶Sephadex LH-20、半自动制备液相等色谱方法对银线草的乙酸乙酯部位进行分离纯化,通过1D-NMR、紫外(UV)光谱、质谱(MS)技术对化合物的结构进行鉴定。结果:从银线草75%乙醇提取物的乙酸乙酯部位共分离得到9个化合物,分别鉴定为金合欢素(1)、千层纸素A(2)、7 E-3,4-二氧甲基苯并[2-苯基-胸苷](3)、落叶松脂素(4)、9α-羟基紫菀内酯(5)、银线草醇B(6)、金粟兰素C(7)、白术内酯Ⅲ(8)、白术内酯Ⅱ(9)。结论:化合物14为首次在金粟兰属中分离得到。 相似文献
6.
目的 比较林下种植重楼和珠子参根际土壤与原生林地土壤特征差异,了解植被变化对土壤特征的影响。方法 以林下移栽种植重楼和珠子参为对象,测定根际土壤特征并与相对应的原生林地土壤数据进行比较。结果 珠子参根际土壤有机碳(46.14 g·kg–1)、有机质(79.55 g·kg–1)、全钾(9.65 g·kg–1)和硝态氮(0.006 g·kg–1)质量分数较高,而全磷(0.49 g·kg–1)、速效磷(0.03 g·kg–1)和铵态氮(0.01 g·kg–1)质量分数的最高值出现在重楼根际土壤中。原生林地土壤中蔗糖酶(51.66 mg·g–1·d–1)、脲酶(372.6 μg·g–1·d–1)、过氧化氢酶(9.65 μmol·g–1·d–1)和亚硝酸还原酶(932.04 μmol·g–1·d–1)活性最高。重楼根际土壤脲酶活性高于珠子参根际土壤,亚硝酸还原酶活性则与之相反,其他几种酶的活性在2种药用植物根际土壤间差异无统计学意义。主成分分析和冗余分析发现,3种土壤在养分构成、理化性质和酶活性方面的变化趋势不同。结论 土壤特征之间差异表明,植被类型养分需求和获取策略有所不同,酶活性及其与土壤理化性质的相关性受到植株自身生理状态和环境条件的双重影响,且往往出现复杂的网状联系。探明药用植物适宜的土壤类型差异能为引种栽培区域划分提供参考。 相似文献
7.
目的:研究巨噬细胞与多疣壁虎断尾再生的关系.方法:多疣壁虎120只,断尾后随机分为野生型组(正常组)、生理盐水组(免疫正常组)、生理盐水+氢化可的松组(免疫抑制组)和生理盐水+脂多糖组(免疫增强组).免疫抑制组腹腔注射氢化可的松80μg·g-1·d-1;免疫增强组注射脂多糖10 μg·g-1·d-1;采用免疫组织化学检测巨噬细胞组织定位.结果:在壁虎断尾再生过程中,横断创面巨噬细胞的浸润定位层次是改变的,断尾12 h后迁移到尾巴断截面附近的巨噬细胞数量达到峰值.免疫正常组、增强组在断尾后24 h与免疫抑制组相比较,断面附近巨噬细胞的数量显著增加.结论:巨噬细胞有可能参与多疣壁虎断尾再生过程. 相似文献
8.
目的研究膨大素对川麦冬生长发育及其产量、质量的影响。方法在收获期随机采样测定川麦冬的生物学性状及产量,用SPSS软件分析川麦冬生物学性状与产量的相关性规律;用UV法测定川麦冬中的总皂苷,考察膨大素的施用量和施用方式对其质量的影响。结果川麦冬的植株生物学性状(除块根直径、株高外)对产量均有显著影响,影响程度为单株块根重>块根数>分蘖数>块根长>百粒重>冠幅。膨大素能促进川麦冬植株地上部分的生长,明显增加块根数、单株块根重,显著提高川麦冬的产量;除低剂量外,膨大素降低了川麦冬总皂苷的含量,且随着剂量的增加,作用越强。结论膨大素能促进川麦冬的生长发育,显著提高川麦冬的产量,且与多效唑分段合用时效果更佳。不同剂量膨大素对川麦冬总皂苷含量的影响差异较大,低剂量有利于川麦冬总皂苷的积累。 相似文献
9.
10.
Fate of Worn‐Out Functional Teeth in the Upper Jaw Dentition of Sicyopterus japonicus (Gobioidei: Sicydiinae) During Tooth Replacement 下载免费PDF全文
Noriyuki Sahara Keita Moriyama Midori Iida Shun Watanabe 《Anatomical record (Hoboken, N.J. : 2007)》2018,301(1):111-124
Mochizuki and Fukui (Jpn J Ichthyol 30 ( 1983 ) 27–36) studied the development and replacement of the upper jaw teeth in a Japanese fish species, Sicyopterus japonicus (Gobioidei: Sicydiinae), and they reported that worn‐out functional teeth in the upper jaw were not shed outside the skin but were taken into the soft tissue of the upper jaw and completely resorbed there. To date, however, this phenomenon appears poorly documented. Furthermore, the mechanism for the resorption of these teeth remains to be determined. In this study, we examined this phenomenon by using 3D microcomputed tomography (m‐CT), scanning electron microscopy (SEM), and various techniques of light (LM) and electron (EM) microcopy. This study demonstrated that the upper jaw dentition of this fish was more or less simultaneously replaced with the replacement occurring during short time periods and that the lingual movement of the replacement teeth to the functional tooth position advanced simultaneously in a given row. Furthermore, our study also revealed that many worn‐out functional teeth were engulfed by the oral epithelium, invaginated into the lingual shallow ditch of the premaxilla, and were resorbed/degraded completely by numerous foreign body giant cells rather than by odontoclasts during periods of at least three intervals of tooth replacement. The complete resorption/degradation of worn‐out functional teeth in the soft tissue of the upper jaw suggests the possibility of the reuse of their components (minerals such as Ca and P, including Fe) for rapid and successional production of new replacement teeth in the upper jaw of adult S. japonicus. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:111–124, 2018. © 2017 Wiley Periodicals, Inc. 相似文献