Simultaneous determination of Levetiracetam and its acid metabolite (ucb L057) in serum/plasma by liquid chromatography tandem mass spectrometry

ObjectiveLevetiracetam and its acid metabolite have almost identical MRMs. They therefore need to be separated chromatographically prior to quantitation.Research design and methodsThe sample is deproteinized with acetonitrile containing Ritonavir as internal standard, centrifuged and the supernatant diluted with water (1:2 v/v). Sixty microliters of the supernatant is injected into the LC–MS/MS and Levetiracetam (LEV) and LEV metabolite separated chromatographically at room temperature employing a Supelco C₁₈ column and a 0.1% formic acid methanol gradient at pH of 2.5.ResultsThe retention times for LEV metabolite, LEV and Ritonavir were 4.50, 5.38 and 9.18 min, respectively. Calibration curves in spiked plasma were linear over the concentration range of 0–50 μg/mL for LEV and 0.0–5.0 µg/mL for LEV metabolite. Intra- and inter-run imprecision (n = 10) gave CVs of 2.3–4.7%, 3.4–8.9% for LEV and 2.9–3.9%, 3.3–7.4% for LEV metabolite. Recoveries of both LEV and LEV metabolite were close to 100%. Results for LEV were compared with those obtained by a commercial reference laboratory (r = 0.974).ConclusionThe procedure is reliable, quick, and inexpensive. LEV and LEV metabolite co-elute using C-18 columns at pHs > 3.0 and previously published methods employing these conditions could therefore be subject to metabolite interference. In this method LEV and LEV metabolite are separated at pH 2.5. The total run time including the washing step is 10 min/sample, making this method suitable when moderate throughput is needed such as in clinical or commercial reference laboratories.     

Secretory breast carcinoma in a 10 years old boy

1 Introduction
Secretory breast carcinoma（SBC） is a rare（〈 1%） type of breast carcinoma,which was initially termed ＂Juvenile breast cancer＂ by McDivitt and Stewart,based on the fact that the average age of the 7 patients described in their report was 9 years old with a range of 3 to 15 years.     

反相高效液相色谱法测定玄麦甘桔颗粒中甘草酸含量

目的建立测定玄麦甘桔颗粒中甘草酸含量的反相高效液相色谱（RP-HPLC）法。方法采用Inertsil ODS-3色谱柱（250mm×4．6mm，5μm），流动相为甲醇-0．5％醋酸铵溶液-冰醋酸（68：32：0．5），流速为1．0mL／min，检测波长为250nm，柱温为室温；并以甘草酸单铵盐为对照品，用外标法测定玄麦甘桔颗粒中甘草酸的含量。结果甘草酸单铵盐对照品质量浓度在38．04—190．2μg／mL范围内与峰面积线性关系良好，线性回归方程A=5753．99C-5951．70，r=0．9999（n=5）；平均回收率为99．67％，RSD=0．49％（n=9）。结论RP—HPLC法分离度好．快速、简便,专属性强,重现性好．准确唐高．可用于测定玄砉甘桔颗粒巾的甘草酸会量．     

动态浊度法测定注射用还原型谷胱甘肽的细菌内毒素含量

目的应用动态浊度法定量测定注射用还原型谷胱甘肽中细菌内毒素的含量。方法通过干扰试验确定样品检测浓度，建立标准曲线并对样品进行细菌内毒素的定量检测。结果注射用还原型谷胱甘肽稀释至质量浓度为1mg／mL时，对鲎试剂检查无干扰作用，细菌内毒素的回收率均在50％～200％范围内。结论用动态浊度法测定注射用还原型谷胱甘肽中的细菌内毒素含量，方法可行。     

p53、bFGF和MVD的表达与垂体腺瘤侵袭性的关系

目的 探讨p53、碱性成纤维生长因子(basic fibroblast growth factor,bFGF)和MVD的表达与垂体腺瘤侵袭性发生之间的关系.方法 将63例垂体腺瘤手术标本分为侵袭组和非侵袭组,采用免疫组化检测p53、bFGF蛋白的表达,检测CD34标记的血管内皮细胞并计数MVD;RT-PCR法检测p53、bFGF mRNA 的表达,分析侵袭组和非侵袭组p53、bFGF和MVD表达水平的差异和相关性.结果 63例垂体瘤患者中,34例为侵袭性垂体腺瘤,29例为非侵袭性垂体腺瘤.侵袭性垂体腺瘤组的p53、bFGF蛋白和mRNA表达均较非侵袭性腺瘤组增高,其MVD计数也较非侵袭性腺瘤组增高.Pearson相关分析显示:侵袭性腺瘤组中p53与bFGF mRNA表达呈正相关(r=0.62,P＜0.01); p53 mRNA表达与MVD计数呈正相关(r=0.69,P＜0.01);bFGF mRNA表达与MVD计数呈正相关(r=0.81,P＜0.01).结论 p53、bFGF、MVD可作为判断垂体腺瘤侵袭性和评估预后的良好生物学指标.     

氯雷他定片的制备及质量控制

目的:制备氯雷他定片并建立其质量控制方法。方法:将氯雷他定与十二烷基硫酸钠、淀粉、微晶纤维素等辅料混合制备片剂。采用紫外分光光度法测定氯雷他定含量。结果:氯雷他定检测浓度线性范围为4~28μg/ml(r=0.9 999),平均回收率为99.9%,相对标准偏差为0.3%。结论:该制剂制备工艺简单,质量控制方法可行。     

子宫内膜癌p53表达的临床意义研究

目的 :探讨p5 3蛋白表达与子宫内膜癌分期、预后及生存率的关系 ,建立有效的判断子宫内膜癌预后和辅助治疗的客观指标。方法 :应用S P免疫组化法检测 10 4例子宫内膜癌p5 3蛋白表达 ,分析p5 3表达与手术病理分期、病理类型、病理学分级等预后因素及生存率的关系。结果 :p5 3蛋白表达与子宫内膜癌临床分期、病理类型、组织病理学分级、淋巴结转移、肿瘤肌层浸润及生存率有明显相关性。结论 :检测子宫内膜癌p5 3蛋白表达对分期、疗效预测、生存率判断有明确的临床指导意义     

刺五加的微乳液毛细管电动色谱指纹图谱研究

目的:在比较毛细管胶束电动色谱(MEKC)和毛细管区带电泳后(CZE)采用微乳液毛细管电动色谱法对刺五加进行指纹图谱的研究。方法:以1.0%(w/w)SDS,6.6%(w/w)正丁醇,0.7%(w/w)正庚烷,25 mmol/L硼砂溶液(91.6%,w/w,pH 9.5)的微乳液为运行介质,波长为222 nm。结果:与毛细管区带电泳、毛细管胶束电动色谱相比,微乳液毛细管电动色谱对刺五加提取物中的复杂组分具有很好的分离能力;指纹图谱中标定了12个指纹峰,重现性、稳定性和方法的精密度较好。结论:微乳液毛细管电动色谱指纹图谱对刺五加的质量控制优于MEKC和CZE法。