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目的:建立HPLC/TQ-MS测定益母草中阿魏酸含量的方法并测定不同产地益母草中阿魏酸含量,评价益母草中阿魏酸对中成药调经止痛片及新生化颗粒的质量影响,为制定含有益母草并以阿魏酸为定量指标的中成药质量标准提供参考。方法:采用薄层色谱法及UPLC-Q/TOF定性鉴别及分析益母草中阿魏酸,采用HPLC/TQ-MS定量分析10批不同产地益母草中阿魏酸含量。基于定量分析结果及处方用量探讨益母草中阿魏酸含量对其中成药质量标准的影响。结果:薄层鉴别及UPLC-Q/TOF定性分析结果显示,10批不同产地益母草中均含有阿魏酸。HPLC/TQ-MS定量分析结果显示,益母草中阿魏酸含量在0.004 2%~0.006 5%之间。结论:益母草与当归、川芎等含有阿魏酸的药材配伍且其用量较大时,益母草中阿魏酸含量会对其质量评价产生一定的影响。  相似文献   
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1. The present study is designed to investigate the brain distribution and plasma pharmacokinetics profiles of chlorogenic acid (CGA) after intranasal administration in Charles–Foster rats to evaluate whether the CGA molecules are transported directly via the nose-to-brain path.

2. The CGA is administered intravenously (IV) and intranasally (IN) at the dose of 10?mg/kg. Further, its concentration in the plasma, cerebrospinal fluid (CSF) and the whole brain is analyzed by HPLC-UV method.

3. The study observes that CGA is rapidly absorbed in plasma with tmax of 1?min similar to IV route after IN administration. The peak plasma concentration and AUC0–24 are higher by 3.5 and 4.0 times respectively in IV administration, compared to IN delivery that represents the significant less systemic exposure of CGA in IN route.

4. However, the concentration of CGA in the brain is 4, 6.5, 5.3, 5.2 and 4.5 times higher at 30, 60, 120, 240 and 360?min, respectively in IN administration compared to IV administration. The exposure of CGA in the brain after IN administration (AUCbrain, IN) was significantly greater (4 times) as compared to the exposure of CGA in the brain (AUCbrain, IV) after IV administration reflecting significant brain uptake of CGA through nasal route. Therefore, IN delivery of CGA can be a promising approach for the treatment of stroke and neurodegenerative disorders.  相似文献   

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BackgroundAccurate diagnosis of the disease extension of cholangiocarcinoma (CCA) is often difficult in clinical practice. The diagnostic yield of conventional pre-operative imaging or endoscopic procedures is sometimes insufficient for the evaluation of longitudinal spreading of CCA. Here we investigated the usefulness of 5-aminolevulinic acid (5-ALA) for the pre- or intra-operative diagnosis of CCA, using patient-derived organoids.MethodsFour CCA- and two adjacent tissue-derived organoids were established. After 5-ALA treatment, we assessed their photodynamic activity using fluorescence microscopy.ResultsCCA organoids established from different patients showed diverse morphology in contrast to monolayer structures of non-tumor organoids, and had the ability to form subcutaneous tumors in immunodeficient mice. CCA organoids demonstrated remarkably high photodynamic activity based on higher accumulation of protoporphyrin IX as a metabolite of 5-ALA compared to non-tumor organoids (40–71% vs. < 4%, respectively). Importantly, cancer cell-specific high photodynamic activity distinguished the organoids originated from biliary stenotic lesions from those of non-stenotic lesions in a CCA patient. The high photodynamic activity did not depend on the expression profile of heme biosynthesis genes.ConclusionsDistinct 5-ALA-based photodynamic activity could have diagnostic potential for the discrimination of CCA from non-tumor tissues.  相似文献   
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Cutaneous wound pain causes physical and psychological stress for patients with wounds. Previous studies reported that stress induces hyperalgesia and deteriorates wound healing. However, the effect of the stress response such as in hypothalamic‐pituitary‐adrenal (HPA) axis on local wound area is unclear. We aimed to investigate the effects of a stress response on the mechanical withdrawal threshold in the local wound area and describe the identification of a wound pain exacerbation. We topically injected adrenocorticotropic hormone (ACTH) into the granulation tissue of full‐thickness cutaneous wound model rats on the fifth day postwounding and measured the mechanical withdrawal thresholds, cytochrome P450 2Bs levels and concentration of 5,6‐epoxyeicosatrienoic acid in wound exudate. We found that ACTH induced mechanical hypersensitivity at 4 and 6 hours after injection (P = .004 and .021, respectively), and increased gene expression of cytochrome P450 2B12 expression (P = .046). Concentration of 5,6‐EET in the wound exudate was moderately correlated with the mechanical withdrawal threshold (r = ?.630). Finally, the mechanical withdrawal threshold in the 5,6‐EET group was significantly lower than that in the control group at 2 hours after the injection (P = .015). We propose that 5,6‐EET is one of the most promising contributors to the wound pain exacerbation. These findings could guide clinical wound and pain management.  相似文献   
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