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1.
枳实薤白桂枝汤HPLC指纹图谱及10种指标成分含量测定研究 总被引:3,自引:0,他引:3
目的建立枳实薤白桂枝汤HPLC指纹图谱分析方法和复方中10种指标成分(辛弗林、槲皮素、桂皮酸、厚朴酚、柚皮苷、腺苷、香豆素、橙皮苷、和厚朴酚、新橙皮苷)含量测定方法,开展相关评价分析。方法采用HPLC法建立枳实薤白桂枝汤指纹图谱,开展相似度评价研究;测定复方中10个指标成分,分析复方中药材不同配伍对其量的变化影响;采用聚类分析等化学计量学方法,对获取相关数据进行分析,评价枳实薤白桂枝汤的质量控制相关指标的影响和价值。结果 10批样品的相似度在0.376~0.990,部分批次相似度大于0.9(5批),说明10批样品相似度差异较大。10批样品中S1~S3、S5、S6、S8、S10为一组,S4、S9为一组,S7单独为一组。共标定了30个特征峰,经主成分分析,主成分1~6是影响药材样品质量评价的主要因子;30个特征峰中对样品分组起关键作用的成分为21(新橙皮苷)、26、29(和厚朴酚)、3、23、17、30(厚朴酚)、5、24(香豆素)、28和7。含量测定结果显示,除槲皮素外,其余9种成分在测定的质量浓度范围内线性关系、精密度、稳定性和重复性良好;不同配伍会对药材中相关成分产生增加或抑制溶出的作用。结论所建立的HPLC方法可用于同时测定枳实薤白桂枝汤中10种化学成分的含量,该方法高效、准确、重复性好,可用于枳实薤白桂枝汤的质量控制和评价。 相似文献
2.
Liping Lin Megumi Suda Chenlan Xu Yuehan Zhang Yukie Yanagiba Jisheng Nie Tamie Nakajima Zuquan Weng Rui-Sheng Wang 《Journal of applied toxicology : JAT》2020,40(7):979-990
Owing to the use of ethyl tert-butyl ether (ETBE) as a fuel additive, the possible adverse effects of ETBE exposure have become a public concern. Our previous study showed that ETBE-induced toxicity in aldehyde dehydrogenase 2 (Aldh2) gene knockout (KO) mice was caused by its primary metabolite acetaldehyde, which was toxic. However, it is unclear whether tert-butyl alcohol (TBA), another main metabolite of ETBE, plays a role in ETBE-induced toxicity. To investigate this relationship, we analyzed the changes of TBA concentrations in tissues after ETBE exposure, and then evaluated the toxicity after direct TBA treatment in both KO and wild-type (WT) mice. An exposure to 500 ppm ETBE via inhalation resulted in the formation of its three metabolites, TBA, 2-methyl-1,2-propanediol and ethanol, whose concentrations in the liver, brain, fat and testis of male KO mice were significantly higher than the corresponding concentrations observed in male WT mice. Direct treatment to TBA (20 mg/mL of drinking water) caused significant changes in relative organ weights and histopathology, and increased levels of genetic damages in both types of mice. These toxic effects were also seen in KO mice exposed to a lower concentration of TBA (5 mg/mL), which was associated with increased oxidative stress in serum (reduced glutathione and reduced glutathione/oxidized glutathione ratio decreased). Our findings indicate that ALDH2 is involved in the metabolism of ETBE and TBA, and ALDH2 deficiency could greatly increase the sensitivity to TBA-induced toxicity. 相似文献
3.
基于中心复合序贯设计法丹参川芎嗪注射液水沉工艺优化 总被引:3,自引:2,他引:1
目的基于质量源于设计(QbD)理念和序贯设计法优化丹参川芎嗪注射液前处理过程中的水沉工艺。方法研究联用了鱼刺图法及基于全局式序贯设计的中心复合实验法作为优化方法,在基础实验设计中关键参数维度的轴向方向增加实验点,再进行新的多元线性回归拟合,最终得到了水沉工艺的设计空间并对其进行了验证,同时给出了较为稳健且全面的操作空间。结果根据设计空间,推荐操作空间为水沉体系pH值为3.1~3.4时,加水倍量3.25~5.00,静置时间为7~17 h,静置温度为7℃。结论首次在中药制药过程工艺优化中引入序贯设计法。相较于样本量巨大的均匀空间网格设计、正交设计等实验设计方法而言,序贯设计在实现与前者同样的样本对可行域覆盖程度的基础上,能够有效降低工艺优化实验的工作量,避免样本与人力物力的浪费,同时保证较高的模型预测性能。 相似文献
4.
Hyla Allouche‐Arnon Yonatan Hovav Lanette Friesen‐Waldner Jacob Sosna J. Moshe Gomori Shimon Vega Rachel Katz‐Brull 《NMR in biomedicine》2014,27(6):656-662
A kinetic model is provided to obtain reaction rate constants in successive enzymatic reactions that are monitored using NMR spectroscopy and hyperpolarized substrates. The model was applied for simulation and analysis of the successive oxidation of choline to betaine aldehyde, and further to betaine, by the enzyme choline oxidase. This enzymatic reaction was investigated under two different sets of conditions: two different choline molecular probes were used, [1,1,2,2‐D4, 1‐13C]choline chloride and [1,1,2,2‐D4, 2‐13C]choline chloride, in different MR systems (clinical scanner and high‐resolution spectrometer), as well as in different reactors and reaction volumes (4.8 and 0.7 mL). The kinetic analysis according to the model yielded similar results in both set‐ups, supporting the robustness of the model. This was achieved despite the complex and negating influences of reaction kinetics and polarization decay, and in the presence of uncontrolled mixing characteristics, which may introduce uncertainties in both effective timing and effective pulses. The ability to quantify rate constants using hyperpolarized MR in the first seconds of consecutive enzyme activity is important for further development of the utilization of dynamic nuclear polarization‐MR for biological determinations. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
5.
Effect of propanal and diacetyl on quantity of remaining double bonds of chemically cured BisGMA/TEGDMA resins 总被引:1,自引:0,他引:1
The aim of the present study was to determine the effect of propanal and diacetyl addition on the quantity of remaining double bonds of chemically cured dental resins. Propanal (propionaldehyde) or diacetyl (2.3-butanedione) was added to monomer mixtures, which were then made chemically curable. The monomer mixtures were varied with respect to content of propanal or diacetyl. Addition of propanal or diacetyl to chemically curable resins resulted in a decrease in the quantity of remaining double bonds from 19.6% to 1.9% and from 19.6% to 11.4%, respectively. A negative correlation of statistical significance was found between content of propanal and quantity of remaining double bonds, while the relationship between content of diacetyl and quantity of remaining double bonds was found not to be linear. Propanal was equally effective in reducing the quantity of remaining double bonds in chemically cured and in the light cured resins studied previously. As regards diacetyl, a more pronounced effect on quantity of remaining double bonds was noted for light cured resins as compared with chemically cured resins. The most likely common reaction mechanism of propanal and diacetyl seemed to be that of chain transfer reactions. Furthermore, analysis of the data indicated a possible additional photoinitiating function of diacetyl. 相似文献
6.
目的:探讨肾衰宁胶囊治疗早中期慢性肾衰竭(CRF)患者的临床疗效及患者肾功能指标的变化。方法:选取2012年3月至2014年12月本院收治的早中期CRF患者82例,随机分为对照组及观察组,每组41例。对照组在常规治疗的基础上给予包醛氧淀粉治疗,观察组在对照组的基础上联合肾衰宁胶囊治疗,2个月为1个疗程,2组患者均连续治疗2个疗程。统计2组患者临床疗效及主要临床症状积分,检测治疗前后2组患者Hb、Alb、24 h UPQ及UA的变化;比较治疗前后2组患者肾功能指标。结果:观察组临床总有效率为85.37%,较对照组的46.34%显著提高(P0.01);与治疗前比较,治疗后对照组仅食少纳呆及肢体麻木积分明显降低,而观察组面色晦暗、食少纳呆、倦怠乏力、腰膝酸软、肢体麻木及口淡不渴积分均明显降低,且显著低于对照组(P0.05或P0.01);与治疗前比较,治疗后对照组Hb、Alb含量明显降低,而观察组无显著变化,且显著高于对照组(P0.05或P0.01);2组患者24 h UPQ及观察组Cys-C、BUN、Scr水平均显著降低,且观察组上述指标均明显低于对照组(P0.01);观察组Ccr明显升高,且明显高于对照组(P0.05或P0.01);2组患者UA含量均无显著变化(P0.05)。结论:肾衰宁胶囊可明显改善早中期CRF患者主要临床症状,阻碍CRF进展,还可调节患者肾脏血流循环,促进患者肾功能恢复,疗效显著优于常规治疗。 相似文献
7.
摘 要:目的:建立白虎加桂枝汤中芒果苷、新芒果苷、甘草酸、甘草苷、肉桂酸5个有效指标性成分的含量测定方法,为白虎加桂枝汤的颗粒研发奠定基础。方法:采用HPLC-PDA双波长同时测定,Waters xBridge BEH C18(4.6 mm×250 μm,5 μm)色谱柱,流动相乙腈-0.01%甲酸水,梯度洗脱,流速1 mL?min-1,柱温30℃,检测波长255 nm、280 nm。结果:70 min内芒果苷、新芒果苷、甘草酸、甘草苷、肉桂酸线性范围分别为66-1976 μg(r=0.999 3),70-3487 μg(r=0.999 7),30-913 μg(r=0.999 5),35-1734 μg(r=0.999 5),0.6-187 μg(r=0.999 8),加样回收率平均范围95.29%-100.17%。结论:建立了白虎加桂枝汤中5个有效指标性成分的含量测定方法,该方法简捷、稳定、准确,可为白虎加桂枝汤及其复方颗粒研制的质量控制提供评价方法。 相似文献
8.
目的研究桂野桐Mallotus conspurcatus中的化学成分。方法采用各种色谱分离手段对桂野桐75%乙醇粗提物的醋酸乙酯萃取部分进行分离纯化。运用1H-NMR、13C-NMR、ESI-MS等波谱方法以及与文献数据对比,鉴定化合物结构。结果从桂野桐根中分离得到18个化合物,分别鉴定为1,5-二羟基-3-甲氧基-7-甲基蒽醌(1)、(-)-丁香脂素(2)、2,3-二羟基-5,7-二-甲氧基-2,8-二甲基-6-(3-甲基-2-丁基)-吡喃-4-酮(3)、2,3-二氢-5,7-二羟基-2,6,8-三甲基-吡喃-4-酮(4)、paeoveitol B(5)、pinellic acid(6)、反式对羟基肉桂酸(7)、反式对甲氧基肉桂酸(8)、反式对羟基肉桂酸乙酯(9)、对羟基苯甲酸(10)、3-甲氧基-4-羟基苯甲酸(11)、3,4-二羟基苯甲酸(12)、阿魏酸(13)、丁香酸(14)、丁香酸乙酯(15)、1-正十六酸甘油酯(16)、没食子酸(17)和没食子酸乙酯(18)。结论除化合物3、4和13外,其余均为首次从野桐属植物中分离得到。 相似文献
9.
Wei H Koivisto A Saarnilehto M Chapman H Kuokkanen K Hao B Huang JL Wang YX Pertovaara A 《Pain》2011,152(3):582-591
The transient receptor potential ankyrin 1 (TRPA1) ion channel is expressed on nociceptive primary afferent neurons. On the proximal nerve ending within the spinal dorsal horn, TRPA1 regulates transmission to spinal interneurons, and thereby pain hypersensitivity. Here we assessed whether the contribution of the spinal TRPA1 channel to pain hypersensitivity varies with the experimental pain model, properties of test stimulation or the behavioral pain response. The antihypersensitivity effect of intrathecally (i.t.) administered Chembridge-5861528 (CHEM; a selective TRPA1 channel antagonist; 5-10 μg) was determined in various experimental models of pain hypersensitivity in the rat. In spinal nerve ligation and rapid eye movement (REM) sleep deprivation models, i.t. CHEM attenuated mechanical hypersensitivity. Capsaicin-induced secondary (central) but not primary (peripheral) mechanical hypersensitivity was also reduced by i.t. administration of CHEM or A-967079, another TRPA1 channel antagonist. Formalin-induced secondary mechanical hypersensitivity, but not spontaneous pain, was suppressed by i.t. CHEM. Moreover, mechanical hypersensitivity induced by cholekystokinin in the rostroventromedial medulla was attenuated by i.t. pretreatment with CHEM. Independent of the model, the antihypersensitivity effect induced by i.t. CHEM was predominant on responses evoked by low-intensity stimuli (?6 g). CHEM (10 μg i.t.) failed to attenuate pain behavior in healthy controls or mechanical hypersensitivities induced by i.t. administrations of a GABAA receptor antagonist, or NMDA or 5-HT3 receptor agonists. Conversely, i.t. administration of a TRPA1 channel agonist, cinnamon aldehyde, induced mechanical hypersensitivity. The results indicate that the spinal TRPA1 channel exerts an important role in secondary (central) pain hypersensitivity to low-intensity mechanical stimulation in various pain hypersensitivity conditions. 相似文献
10.
Chrostek L Jelski W Szmitkowski M Puchalski Z 《Journal of clinical laboratory analysis》2003,17(3):93-96
Alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH), which are most abundant in the liver, are the main enzymes involved in ethanol metabolism in humans. Gender-related differences in total liver ADH and ALDH activity among different animal species have been observed in many studies. We measured total ADH and ALDH activity, and the activity of class I-IV ADH in the livers of male and female patients. Total ADH and class I and II ADH activities were significantly higher in males than in females (P=0.0052, P=0.0074, P=0.020, respectively). Class III and IV ADH and total ALDH activities were not significantly different between the genders (P=0.2917, P=0.0590, P=0.2940, respectively). The results of our study clearly show that there is a difference in enzymatic activity between male and female patients for those isoenzymes that actively participate in ethanol oxidation in the liver (class I and II ADH), although the main form of ADH in this organ is class III ADH. 相似文献