超高效液相色谱-串联质谱法同时快速检测微量血清中6种脂溶性维生素

目的 建立超高效液相色谱-串联质谱法（UPLC-MS/MS）同时快速检测微量血清中维生素A、维生素D（25-OH-VD2 、25-OH-VD3 ）、维生素E（α-、β-和γ-生育酚）的方法。方法 血清中脂溶性维生素经甲醇-乙腈（50:50, v/v)沉淀蛋白、正己烷萃取,以Phenomenex Kinetex F5色谱柱为分离柱,2.5 mmol/L甲酸铵-0.1%甲酸水溶液和甲醇为流动相,梯度洗脱,电喷雾电离（ESI+ ）、多反应监测（MRM）模式下检测,同位素内标法定量。结果 血清中6种脂溶性维生素线性范围内线性关系良好,相关系数 r >0.995;6种脂溶性维生素的检测限为0.20~1.25 ng/ml,定量限为0.39~3.88 ng/ml;加标回收率为86.6%~107.7%,日内精密度<9.6%,日间精密度<9.3%。NIST标准参照品SRM 968f验证方法准确度,结果偏差均在5%以内。结论 本方法准确度高、重现性好、用血量少,适于婴幼儿等采血困难者微量血样中多种脂溶性维生素的同时快速检测。     

蒙脱石散对盐酸左氧氟沙星体外吸附的影响

目的: 探讨蒙脱石散对盐酸左氧氟沙星体外吸附的影响.方法: 采用不同剂量的盐酸左氧氟沙星分别与3 g蒙脱石散混合,加入0.1 mol·L-1盐酸溶液中,在(37±0.5)℃水浴中恒温2 h后过滤,用紫外分光光度法测定盐酸左氧氟沙星的含量变化.结果: 蒙脱石散对盐酸左氧氟沙星的吸附率为(98.37±0.03)%.结论: 蒙脱石散对盐酸左氧氟沙星有极强吸附,因此应避免两种药物同时服用.     

金佛手挥发油化学成分的GC-MS分析

目的:分析金佛手鲜品与干品挥发油的化学成分与相对含量。方法:用色谱-质谱联用法(GC-MS)测定佛手挥发油,结果用计算机检索NIST98数据库。结果:从佛手挥发油中检测出30多种化学成分,主要成分是D-柠檬烯和( )-2-蒈烯,鲜品挥发油中分别为40.02％、21.35％,干品挥发油中分别为38.63％、18.17％。结论:金佛手挥发油的主要成分是柠檬烯与蒈烯。     

双波长分光光度法测定复方苯甲酸酊的含量

目的:建立一种同时测定制剂中各组分含量的分光光度法.方法:采用双波长分光光度法,以75%乙醇为溶媒,不经分离直接测定复方苯甲酸酊中苯甲酸和水杨酸的含量.苯甲酸的测定波长为275 nm,参比波长为326.2 nm;水杨酸的测定波长为302 nm.结果:苯甲酸在24～96μg·ml-1浓度范围内线性关系良好(r=0.999 9),平均回收率为100.5%,RSD为0.5%,水杨酸在6～36μg·ml-1浓度范围内线性关系良好(r=0.999 9),平均回收率为99.8%,RSD为0.5%.结论:本法快速,简便,结果准确.     

Tailoring antimicrobials in febrile neutropenia: using faster diagnostic and communication tools to improve treatment in the era of extensively resistant pathogens

Febrile Neutropenia represents a medical emergency and the use of appropriate antimicrobial therapy is essential for a better outcome. Although being time-consuming, conventional cultures and antimicrobial susceptibility tests remain the golden standard practices for microbiology identification. Final reports are typically available within several days. Faster diagnostic tools, such as species identification trough Matrix Assisted Laser Desorption Ionization-Time of Flight (MALDI-TOF) and molecular techniques might help to shorten time to diagnostic and also guide definitive therapy in this scenario. Here we present a case in which the use of a diagnostic molecular workflow combining MALDI-TOF and real-time PCR for relevant genes codifying antibiotic resistant integrated with instant communication report, led to a tailored and more appropriate treatment in a patient presenting with febrile neutropenia.     

3-chlorotyrosine in Sputum of COPD Patients: Relationship with Airway Inflammation

ABSTRACT

The airways of patients with chronic obstructive pulmonary disease (COPD) are associated with increased numbers of inflammatory cells, in particular neutrophils and macrophages. Contained within the primary granules of neutrophils is the heme enzyme called myeloperoxidase (MPO) that has been used as a biomarker of neutrophilic inflammation in COPD and other inflammatory diseases. MPO is the only enzyme in the body that produces hypochlorous acid (HOCl), which effectively chlorinates tyrosine residues in proteins. The presence of 3-chlorotyrosine (3Cl-Tyr) in sputum of COPD patients has yet to be established. Spontaneously produced sputum was collected from 14 stable COPD patients, and ultra-centrifuged to prepare sol phase samples for analysis. Sputum 3Cl-Tyr levels were measured using Mass Spectrometry (LC-MSMS). Sputum MPO activity was measured using a standard chromogenic substrate assay. The Spearman rank correlation was used to analyse the data. We report for the first time the measurement of 3Cl-Tyr in sputum from stable COPD patients. The sputum levels of 3Cl-Tyr correlated well with sputum MPO activity (r = 0.88; p < 0.0001). The presence of 3Cl-Tyr in the sputum of stable COPD patients suggests an active process related to MPO that may play a role in the pathophysiology of this disease.     

Determination of dead-layer variation in HPGe detectors

The dead-layer uniformity of the top surface of two high purity germanium detectors has been studied using a novel automated scanning set-up that allows a fine-grained topography of a detector's top and lateral surfaces. Comparisons between measurements and Monte Carlo simulations allowed implementation of a dead-layer variation into the detector model, which reproduces the measurements results. The effect of the non-uniform dead-layer on activity determinations based on low-energy γ-rays (i.e. below ~100 keV) has been determined to be of the order of 10% or more.     

The current status of heart failure diagnostic biomarkers

Heart failure (HF) affects approximately 23 million individuals worldwide and this number is increasing, due to an aging and growing population. Early detection of HF is crucial in the management of this debilitating disease. Current diagnostic methods for HF rely heavily on clinical imaging techniques and blood analysis, which makes them less than ideal for population-based screening purposes. Studies focusing on developing novel biomarkers for HF have utilized various techniques and biological fluids, including urine and saliva. Promising results from these studies imply that these body fluids can be used in evaluating the clinical manifestation of HF and will one day be integrated into a clinical workflow and facilitate HF management.     

The future of proteomics in the study of alcoholism

This article represents the proceedings of a workshop at the 2003 annual meeting of the Research Society on Alcoholism in Fort Lauderdale, FL. The workshop organizers/chairpersons were Chinnaswamy Kasinathan and Paul Manowitz. The presentations were (1) Introduction to the field of proteomics, by Kent Vrana; (2) Use of proteomics in the identification of urinary biomarkers for alcohol intake, by Chinnaswamy Kasinathan, Paul Thomas, and Paul Manowitz; (3) Proteomics screening illuminates ethanol-mediated induction of HDL proteins in macaques, by Kent Vrana, Randy Gooch, Travis Worst, Stephen Walker, Aaron Xu, Peter Pierre, Heather Green, and Kathleen Grant; and (4) Proteomics applied to the study of the liver, by Laura Beretta.     

大鼠心肌缺血预适应延迟相的差异蛋白质的分离及鉴定

目的采用蛋白质组学技术探讨缺血预适应心肌内源性保护的分子机制。方法应用双向凝胶电泳技术分离假手术组和心肌缺血预适应延迟相组大鼠的心肌总蛋白质。结果在假手术组的双向凝胶电泳图谱上展示704±27个蛋白质点,而在心肌缺血预适应延迟相组展示778±35个蛋白质点。经凝胶图像分析找到的差异蛋白质23个,基质辅助激光解析—电离飞行时间质谱对差异蛋白进行鉴定,共鉴定出12个蛋白质。这些蛋白质包括应激反应蛋白、代谢相关蛋白、信号调节蛋白、结构蛋白等。结论这些差异蛋白可能通过其分子伴侣功能、清除自由基、改善能量代谢等发挥心肌缺血预适应延迟相的心肌保护作用。