RP-HPLC法测定熊去氧胆酸胶囊中熊去氧胆酸及有关物质的含量

目的建立反相高效液相色谱法(RP-HPLC)测定熊去氧胆酸胶囊中熊去氧胆酸、胆酸、鹅去氧胆酸及胆石酸的含量。方法使用Diamonsil C18色谱柱(200 mm×4.6 mm,5μm),流动相为乙腈-0.03 mol·L-1磷酸溶液(体积比为40∶60),流速为1.4 mL·min-1,检测波长为205 nm,柱温为35℃。结果熊去氧胆酸胶囊中熊去氧胆酸、胆酸、鹅去氧胆酸及胆石酸在25 min内洗脱并基线分离。熊去氧胆酸、胆酸、鹅去氧胆酸及胆石酸的线性范围分别为0.80²00.00、0.45200.00、0.45¹10.00、0.30110.00、0.30⁷0.00和0.3070.00和0.30⁸0.00 mg·L-1,平均回收率分别为99.7%、99.3%、98.7%和99.1%,RSD分别为1.30%、1.47%、1.87%和1.95%(n=3)。结论 RP-HPLC可用于同时测定熊去氧胆酸胶囊中熊去氧胆酸、胆酸、鹅去氧胆酸及胆石酸的含量,可应用于熊去氧胆酸胶囊胶囊制剂的质量控制。     

甘露醇-旋光法测定鞣柳硼三酸散中硼酸的含量

目的建立旋光法测定鞣柳硼三酸散中硼酸的含量。方法以低浓度明胶溶液提取制剂中硼酸,利用甘露醇结合硼酸形成具有旋光性复合物,并建立鞣柳硼三酸散中硼酸的含量测定方法。结果硼酸浓度在5～20 g.L-1的浓度范围内与旋光度线性关系良好(r=0.999 2),方法的平均回收率为99.98%,RSD为1.3%。结论旋光法测定鞣柳硼三酸散中硼酸的含量,操作简便、快速,结果准确,重现性好。     

咖啡酸、阿魏酸和香草酸对酪氨酸酶活性的影响

目的 :研究咖啡酸、阿魏酸和香草酸对酪氨酸酶活性的影响 ,寻找酪氨酸酶抑制剂 ,从而为治疗色素增加性皮肤病筛选药物。方法 :酪氨酸酶多巴速率氧化法体外测定药物干预前后酪氨酸酶活性 ,求出酪氨酸酶抑制率。采用Lineweaver Burk双倒数法制得酶动力学曲线 ,推断抑制类型。结果 :3种试药中仅香草酸对酪氨酸酶具有抑制作用 ,与氢醌比较无显著差异 (P >0 .0 5 ) ,咖啡酸、阿魏酸对酪氨酸酶具有上调激活作用。结论 :香草酸为良好的混合型酪氨酸酶抑制剂。     

Nalidixic acid prodrugs: Amides from amino acid ester and nalidixic acid

Amides from amino acid ester and nalidixic acid were synthesized. The solubility characteristics and partition coefficient of the compounds were studied. The hydrolysis of the compounds was studied in the simulated gastric fluid and simulated intestinal fluid. Some compounds showed better antibacterial activity than nalidixic acid.     

Oral antipyretic therapy: Evaluation of the N-aryl-anthranilic acid derivatives mefenamic acid,tolfenamic acid and flufenamic acid

Summary The antipyretic activity of three N-aryl-anthranilic acid derivatives, mefenamic acid, tolfenamic acid and flufenamic acid, was compared and their optimal antipyretic dose determined in a trial in 87 children (aged 5 months to 15 years), who suffered from infections and fever exceeding 38.5°C. Tolfenamic acid proved to be the most potent antipyretic agent of the three drugs; it was eight times more powerful than mefenamic acid and three times more powerful than flufenamic acid. The optimal antipyretic doses were: mefenamic acid 4 mg/kg, tolfenamic acid 0.5 mg/kg and flufenamic acid 1.5 mg/kg. It is evident that the antipyretic activity of these anthranilic acid derivatives is even greater than their antirheumatic effect, the difference being most noticeable in the case of tolfenamic acid.     

高效液相色谱法测定鞣柳硼三酸散中水杨酸的含量

目的:探讨用反相高效液相色谱法测定鞣柳硼三酸散中水杨酸的含量。方法:采用Symetry Shield RP18(5μm 4.6mm×250mm)Columm色谱柱;以0.05mol/L磷酸二氢钠缓冲液(pH2.6)-乙腈(50∶50)为流动相;检测波长233nm。结果:水杨酸在20.4～61.2μg/ml浓度范围内呈良好的线性关系,平均回收率为99.0%。结论:本法简便、准确、快速,适用于鞣柳硼三酸散中水杨酸的含量测定。     

高效液相色谱法测定复方苯甲酸乳膏中苯甲酸和水杨酸的含量

目的:建立高效液相色谱法(HPLC)测定复方苯甲酸乳膏中苯甲酸和水杨酸的含量。方法:色谱柱为Hypersil C_(18)柱(4.6nm×250mm,5μm),流动相为甲醇-水(44:56),流速0.8mL·min~(-1),检测波长为226nm。结果:苯甲酸和水杨酸分别在15.20～76.00mg·L~(-1)和7.64～38.20mg·L~(-1)范围内线性良好(r=0.9999);日内、日间RSD在0.030～4.79％,高、中、低浓度回收率在98.54％～101.20％。分析了3批样品,结果满意。结论:本方法简便,快速,准确,可作为复方苯甲酸乳膏的质量控制方法。     

双波长薄层扫描法测定苯甲酸复方制剂的含量

本文采用硅胶HF_(254 366)薄层板,以氯仿—丙酮—异丙醇—甲醇—浓氨水(30:30:15:15:10)为展开剂,直接分离苯甲酸复方制剂中的苯甲酸与水杨酸。在CS-930型双波长薄层扫描仪上,采用反射式锯齿扫描,分别对苯甲酸和水杨酸进行扫描测定。结果:苯甲酸与水杨酸的线性关系、精度及回收率都比较满意。     

Methylated eicosapentaenoic acid and tetradecylthioacetic acid: effects on fatty acid metabolism.

We introduced methyl or ethyl groups to the 2- or 3-position of the eicosapentaenoic acid (EPA) molecule to investigate whether the branching of EPA could influence its hypolipidemic effect in rats. The most effective branching involved two methyl groups in the 2-position and one methyl group in the 3-position. These EPA derivatives increased hepatic mitochondrial and peroxisomal beta-oxidation and decreased plasma lipids concomitant with suppressed acetyl-coenzyme A (CoA) carboxylase (EC 6.4.1.2) and fatty acid synthase (EC 2.3.1.85) activities. This was followed by elevated activities of camitine O-palmitoyltransferase (EC 2.3.1.21) and possibly 2,4-dienoyl-CoA reductase (EC 1.3.1.34), as well as induced mRNA levels of these enzymes and fatty acyl-CoA oxidase. The fatty acid composition in liver changed, with an increased 18:1 n-9 content, whereas the expression of delta9-desaturase remained unchanged. We investigated the flux of fatty acids in cultured hepatocytes, and found that oxidation of [1-14C]-labeled palmitic acid increased but the secretion of palmitic acid-labeled triglycerides decreased after addition of 2-methyl-EPA. The fatty acyl-CoA oxidase (EC 1.3.3.6) activity in these cells remained unchanged. A significant negative correlation was obtained between palmitic acid oxidation and palmitic acid-labeled synthesized triglycerides. To investigate whether the hypolipidemic effect occurred independently of induced peroxisomal beta-oxidation, we fed rats 2-methyl-tetradecylthioacetic acid. This compound increased the peroxisomal but not the mitochondrial beta-oxidation, and the plasma lipid levels were unchanged. In conclusion, EPA methylated in the 2- or 3-position renders it more potent as a hypolipidemic agent. Furthermore, this study supports the hypothesis that the mitochondrion is the primary site for the hypolipidemic effect.     

基于UPLC法同时测定三叉神经散中绿原酸、咖啡酸、阿魏酸和丹酚酸B的含量

目的本文旨在建立一种利用UPLC同时测定三叉神经散中绿原酸、咖啡酸、阿魏酸和丹酚酸B含量的方法。方法采用超高效液相色谱法,采用Kromat Universil XB C18色谱柱(150 mm×2.1 mm,3μm);流动相:乙腈-体积分数0.2%甲酸水溶液;流速:0.2 mL·min~(-1);检测波长:320 nm;进样量:1μL;柱温:30℃。结果绿原酸、咖啡酸、阿魏酸和丹酚酸B质量浓度分别在4.0~24.0 mg·L~(-1),0.2~1.2 mg·L~(-1),0.5~3.0 mg·L~(-1)和8.0~48.0 mg·L~(-1)内与峰面积呈良好的线性关系。绿原酸、咖啡酸、阿魏酸和丹酚酸B的平均回收率分别为(98.1±1.38)%、(97.7±1.10)%、(97.5±1.13)%和(98.3±1.39)%,RSD分别为1.41%、1.13%、1.16%和1.41%(n=9)。对三批样品进行含量测定,绿原酸、咖啡酸、阿魏酸和丹酚酸B的平均含量为(262.919±0.12)、(12.583±0.02)、(26.864±0.06)、(701.947±0.05)μg·g-1。结论本方法快速、简便、准确,可用于三叉神经散中绿原酸、咖啡酸、阿魏酸和丹酚酸B的含量测定。     

一测多评法测定藏茴香中异绿原酸A、新绿原酸、绿原酸、隐绿原酸、异绿原酸B、异绿原酸C

目的 建立一测多评法（QAMS）测定藏茴香中6种咖啡酰奎宁酸类成分含量,并验证该方法在藏茴香质量评价中应用的可行性与适用性。方法 取藏茴香粉末（过三号筛）0.5 g,精密加入70%甲醇 20 mL ,超声处理（250 W、频率 53 kHz）30 min,制备供试品溶液;采用Phenomenex GeminiR C₁₈（250 mm×4.6 mm,5 μm）色谱柱,以乙腈-0.1%甲酸水溶液为流动相,梯度洗脱,检测波长为 330 nm,体积流量 1.0 mL·min^-1,柱温 30 ℃,进行专属性、供试品提取条件、检测波长选择、色谱条件、线性关系、精密度、重复性、稳定性、加样回收率方法学考察,建立异绿原酸A、新绿原酸、绿原酸、隐绿原酸、异绿原酸 B、异绿原酸 C成分含量检测的 HPLC法;以异绿原酸 A为内参成分,分别计算新绿原酸、绿原酸、隐绿原酸、异绿原酸B、异绿原酸C 5种成分的相对校正因子,分别采用3种不同色谱仪和3种色谱柱进行相对校正因子、相对保留时间耐用性考察,对藏茴香样品同时采用外标法与 QAMS 测定 6 种成分的质量分数,比较 2 种测定方法结果的差异。结果 建立的6种成分的HPLC检测方法的专属性、供试品提取条件、检测波长选择、色谱条件、线性关系、精密度、重复性、稳定性、加样回收率均符合要求;新绿原酸、绿原酸、隐绿原酸、异绿原酸B、异绿原酸C的相对校正因子平均值分别是 1.362、1.257、1.335、1.470、1.134,3种不同色谱仪和 3种色谱柱对相对校正因子、相对保留时间均无明显影响;QAMS与外标法2种方法测定3批藏茴香样品中6种成分得到的结果之间无显著差异。结论 建立的QAMS简便、准确、可靠,可用于藏茴香中6种咖啡酰奎宁酸类成分——异绿原酸A、新绿原酸、绿原酸、隐绿原酸、异绿原酸B、异绿原酸C的定量分析。     

All-trans retinoic acid regulates hepatic bile acid homeostasis

Retinoic acid (RA) and bile acids share common roles in regulating lipid homeostasis and insulin sensitivity. In addition, the receptor for RA (retinoid x receptor) is a permissive partner of the receptor for bile acids, farnesoid x receptor (FXR/NR1H4). Thus, RA can activate the FXR-mediated pathway as well. The current study was designed to understand the effect of all-trans RA on bile acid homeostasis. Mice were fed an all-trans RA-supplemented diet and the expression of 46 genes that participate in regulating bile acid homeostasis was studied. The data showed that all-trans RA has a profound effect in regulating genes involved in synthesis and transport of bile acids. All-trans RA treatment reduced the gene expression levels of Cyp7a1, Cyp8b1, and Akr1d1, which are involved in bile acid synthesis. All-trans RA also decreased the hepatic mRNA levels of Lrh-1 (Nr5a2) and Hnf4α (Nr2a1), which positively regulate the gene expression of Cyp7a1 and Cyp8b1. Moreover, all-trans RA induced the gene expression levels of negative regulators of bile acid synthesis including hepatic Fgfr4, Fxr, and Shp (Nr0b2) as well as ileal Fgf15. All-trans RA also decreased the expression of Abcb11 and Slc51b, which have a role in bile acid transport. Consistently, all-trans RA reduced hepatic bile acid levels and the ratio of CA/CDCA, as demonstrated by liquid chromatography-mass spectrometry. The data suggest that all-trans RA-induced SHP may contribute to the inhibition of CYP7A1 and CYP8B1, which in turn reduces bile acid synthesis and affects lipid absorption in the gastrointestinal tract.     

Carnitine and glucuronic acid conjugates of pivalic acid

The [1-14C]pivaloyloxyethyl ester of methyldopa administered to man and cynomolgus monkeys resulted in the elimination in the urine of 14C-pivalic acid metabolites. Pivaloyl glucuronide and pivaloyl carnitine were identified as the major radioactive urinary metabolites in monkey urine and human urine, respectively. N.m.r. analysis indicated that pivaloyl carnitine had a cyclic structure. Although the role of carnitine is in the transport of fatty acids across mitochondrial membranes, it may also function in the conjugation of carboxylic acid xenobiotics in humans.