Improved Magnetic Resonance Molecular Imaging of Tumor Angiogenesis by Avidin-Induced Clearance of Nonbound Bimodal Liposomes

Angiogenic, that is, newly formed, blood vessels play an important role in tumor growth and metastasis and are a potential target for tumor treatment. In previous studies, the α_vβ₃ integrin, which is strongly expressed in angiogenic vessels, has been used as a target for Arg-Gly-Asp (RGD)-functionalized nanoparticulate contrast agents for magnetic resonance imaging-based visualization of angiogenesis. In the present study, the target-to-background ratio was increased by diminishing the nonspecific contrast enhancement originating from contrast material present in the blood pool. This was accomplished by the use of a so-called avidin chase, which allowed rapid clearance of non-bound paramagnetic RGD-biotin-liposomes from the blood circulation. C57BL/6 mice, bearing a B16F10 mouse melanoma, received RGD-functionalized or untargeted biotin-liposomes, which was followed by avidin infusion or no infusion. Precontrast, postcontrast, and postavidin T₁-weighted magnetic resonance images were acquired at 6.3 T. Postcontrast images showed similar percentages of contrast-enhanced pixels in the tumors of mice that received RGD-biotin-liposomes and biotin-liposomes. Post avidin infusion this percentage rapidly decreased to precontrast levels for biotin-liposomes, whereas a significant amount of contrast-enhanced pixels remained present for RGD-biotin-liposomes. These results showed that besides target-associated contrast agent, the circulating contrast agent contributed significantly to the contrast enhancement as well. Ex vivo fluorescence microscopy confirmed association of the RGD-biotin-liposomes to tumor endothelial cells both with and without avidin infusion, whereas biotin-liposomes were predominantly found within the vessel lumen. The clearance methodology presented in this study successfully enhanced the specificity of molecular magnetic resonance imaging and opens exciting possibilities for studying detection limits and targeting kinetics of site-directed contrast agents in vivo.     

血浆甘磷酰芥及代谢物的测定方法和大鼠口服药代动力学

利用甘磷酰芥与4-(4′-硝基苯甲基)-吡啶(NBP)呈显色反应建立了该药及其代谢物在血浆及尿中的定量测定方法。观察了血浆在体外对该药的代谢作用及种属差异。研究了大鼠口服该药的药代动力学。     

反相高效液相色谱法测定甲磺酸酚妥拉明片的含量

目的：建立了反向高效液相色谱法测定甲磺酸酚妥拉明的含量的方法。方法：采用Symmetry C18硅烷键和硅胶柱,甲醇－水－冰醋酸－三乙胺（10：10：1：0．1）作为流动相,检测波长为278nm,峰面积外标法测定。结果：平均回收率为100．2％（n=11),日内、日间差分别为0．7％和0．8％,在10－250μg范围内线性关系良好（r=0.9999),结论：该法简便、准确、结果满意。     

Multidisciplinary Collaborative Care for Depressive Disorder in the Occupational Health Setting: design of a randomised controlled trial and cost-effectiveness study

Background  

Major depressive disorder (MDD) has major consequences for both patients and society, particularly in terms of needlessly long sick leave and reduced functioning. Although evidence-based treatments for MDD are available, they show disappointing results when implemented in daily practice. A focus on work is also lacking in the treatment of depressive disorder as well as communication of general practitioners (GPs) and other health care professionals with occupational physicians (OPs). The OP may play a more important role in the recovery of patients with MDD. Purpose of the present study is to tackle these obstacles by applying a collaborative care model, which has proven to be effective in the USA, with a focus on return to work (RTW). From a societal perspective, the (cost)effectiveness of this collaborative care treatment, as a way of transmural care, will be evaluated in depressed patients on sick leave in the occupational health setting.     

楤木根皮中皂甙化学成分的研究

楤木根皮中的主要成分是皂甙。将总皂甙以柱层析分离,得到三个化合物(Ⅰ～Ⅲ),经光谱分析和化学方法证明,Ⅰ为楤木皂甙A(araloside A);Ⅱ为银莲花甙(narcissiflorine);Ⅲ是3-O-[β-D-吡喃葡萄糖-(1→2)-β-D-吡喃木糖-(1→)2)-α-L-阿拉伯糖]-齐墩果酸。Ⅲ为一新皂甙,命名为楤木皂甙D(araloside D)。     

青蒿琥酯在奶牛体内的药代动力学与代谢

青蒿琥酯(artesunate,AS)是抗疟新药青蒿素的一个活性衍生物。近年来我国兽医工作者将其用于治疗牛羊泰勒氏焦虫病及双芽、巴贝斯焦虫病、鸡球虫病和耕牛血吸虫病,也收到了满意的效果。AS在大白鼠、兔、狗及人体内的药代动力学研究已见报道。本     

独活中欧芹酚甲醚和二氢山芹醇醋酸酯的HPLC法测定(英文)

本文从伞形科植物重齿毛当归(Angelica pubescens Maxim.f.biserrata Shan et Yuan)的干燥根中分离得主要成分欧芹酚甲醚(osthole)和二氢山芹醇醋酸酯(columbianetin acetate)。并以此为对照品,用反相HPLC法测定了独活药材中二者的含量。使用ZORBAXODS 4.6mm×15cm反相柱,甲醇一水(2:1)作流动相,280nm为检测波长,本法简便、快速,为独活的含量测定提供了分析方法。     

沉香螺环化合物的研究:10-甲基-螺[4.5]-癸-6-烯-6-羧酸的合成

3-甲基△²环已烯-1-酮(4)与1,4-二溴丁烷在氨钠,液氨中或在叔丁醇钾的苯溶液中进行螺环化反应,得到螺环化合物5a+5b以及双螺环化合物6a+6b。经定量催化氢化;羰基与三甲基硅氰加成反应;硅醚水解;脱水和腈基水解,合成了10-甲基-螺[4.5]-癸-6-烯-6-羧酸(11)。药理试验表明该化合物有一定的麻醉催眠作用。     

复方烧伤喷雾剂的药效学研究

目的：研究以乙酸乙酯为主要溶媒的复方烧伤喷雾的药效学。方法：用烧伤创面感染常见的金黄色葡萄球菌、绿脓假单胞菌、大肠埃希氏菌、普通变形杆菌做豚鼠烧伤感染模型,并用复方烧伤喷雾剂治疗,结果：复方烧伤喷雾剂可促进豚鼠Ⅱ度烧伤创面的愈合,并具有显著的烧伤创面抗感染作用。结论：乙酸乙酯可作为某些中药有效成分的优良提取溶剂。     

纳米靶向给药系统载体材料的研究进展

目的:综述及讨论近年来新材料在靶向给药系统载体材料方面的应用及存在问题。资料来源:以网络数据库资源为主,查询Science Direct,Pubmed,Springer,Ovid等数据库1995-01/2006-06关于靶向给药系统载体材料方面的相关文献,检索词“Targetdrug delivery system”and“Materials”,限定文章的语种种类为“English”;同时检索CNKI数据库2001-01/2006-06的相关文章为补充,限定文章语种种类为中文,检索关键词“靶向给药系统,载体材料”。资料选择:对资料进行初审,纳入标准:①关于靶向给药系统的研究。②应用的较新的材料作为药物载体。排除标准:重复性研究。资料提炼:共收集到122篇文献,98篇符合纳入标准,取其中有关新型载体材料应用于靶向给药系统的30篇相关文献进行归纳总结。资料综合:靶向给药是目前药剂学领域的研究热点之一,但多年来转化为产品的研究成果极为少见。其中关键问题之一就是药物载体材料的研究瓶颈,药剂学研究与材料学研究间学科交叉与衔接的严重滞后阻碍了新型给药系统的产业化。结论:新型给药系统载体材料研究开发尤为重要,载体材料应用的安全性一旦解决,必将带来新型给药系统全面用于临床的新局面,从而使药效得到更好的发挥,提高疾病的预防治疗能力。