几种手性药物对映体的HPLC分离与生物样品分析

使用ＣＨＩＲＡＬ－ＡＧＰ柱，通过优化色谱条件，以ＨＰＬＣ法对３种手性药物ＳＦＺ－４７〔（±）－３Ｈ－１，２－二氢－２－（４－甲基苯胺基）－甲基－１－吡咯里嗪酮〕，ＫＭＢＺ－００９〔（±）－反式－４－苯基－５－（邻氯苄基）－吡咯烷酮－２〕和地丙苯酮〔（±）－２′－（２－羟基－３－（特戊胺基）丙氧基）－３－苯基苯丙基酮〕进行了对映体的直接分离，达到良好的分离效果．在此基础上测试了动物血浆样品中ＳＦＺ－４７的对映体，对其药物动力学的对映体选择性进行了初步研究．     

Characterization of an arabinogalactan protein from the pressed juice of <Emphasis Type="Italic">Echinacea purpurea</Emphasis>: investigations into the type of linkage between the protein and polysaccharide moieties

A high molecular weight arabinogalactan protein (AGP) from the pressed juice of Echinacea purpurea, known to exhibit immunomodulatory properties in vitro, was characterized. Alkaline hydrolysis was carried out, leading to degradation of the protein core and to carbohydrate moieties linked to the amino acid responsible for binding. Gel permeation chromatography of these AG subunits gave one peak with a molecular weight of 30 × 10³ Da. Hydroxyproline (42.9% w/w) was detected as the dominant amino acid after alkaline hydrolysis and was thus identified as the major amino acid responsible for the binding between the protein and the AG subunits via an O-glycosidic linkage. Large amounts of glutamine/glutamic acid (24.5% w/w) and asparagine/aspartic acid (17.3% w/w) were also found. Polyclonal antibodies raised against the intact AGP were shown to bind to the AG subunits too, indicating that the epitopes responsible for such interactions are localized in the polysaccharide moiety of the AGP.     

Lipophilicity and biomimetic properties to support drug discovery

Introduction: Lipophilicity, expressed as the octanol-water partition coefficient, constitutes the most important property in drug action, influencing both pharmacokinetic and pharmacodynamics processes as well as drug toxicity. On the other hand, biomimetic properties defined as the retention outcome on HPLC columns containing a biological relevant agent, provide a considerable advance for rapid experimental – based estimation of ADME properties in early drug discovery stages.

Areas covered: This review highlights the paramount importance of lipophilicity in almost all aspects of drug action and safety. It outlines problems brought about by high lipophilicity and provides an overview of the drug-like metrics which incorporate lower limits or ranges of logP. The fundamental factors governing lipophilicity are compared to those involved in phospholipophilicity, assessed by Immobilized Artificial Membrane Chromatography (IAM). Finally, the contribution of biomimetic properties to assess plasma protein binding is evaluated.

Expert opinion: Lipophilicity and biomimetic properties have important distinct and overlapping roles in supporting the drug discovery process. Lipophilicity is unique in early drug design for library screening and for the identification of the most promising compounds to start with, while biomimetic properties are useful for the experimentally-based evaluation of ADME properties for the synthesized novel compounds, supporting the prioritization of drug candidates and guiding further synthesis.     

3，5-二硝基水杨酸比色法测定红毛五加中多糖的含量

目的建立红毛五加中多糖的含量测定方法。方法采用3，5-二硝基水杨酸比色法（DNS法），测定红毛五加中的还原糖和总糖的含量，并计算出总多糖的含量。结果以葡萄糖为对照品，线性范围为46．6～233．0mg／L（r=0．9992），加样回收率为99．0％～102．1％；红毛五加中总多糖含量1．3～1．9mg／g。结论本方法灵敏、稳定、重复性好，有助于红毛五加质量控制方法的研究。     

Relationship between elevated levels of the alpha 1 acid glycoprotein in chronic myelogenous leukemia in blast crisis and pharmacological resistance to imatinib (Gleevec) in vitro and in vivo

The Abl tyrosine kinase inhibitor imatinb is becoming a standard for the treatment of chronic myelogenous leukemia (CML). However, Bcr-Abl gene mutations have been reported mainly in relapsing or resistant patients. In primary resistant patients, only few mutations have been documented so far, suggesting alternative mechanisms. We aimed to investigate if alpha 1 acid glycoprotein (AGP), an acute phase drug binding protein, could be a biological marker for pharmacological resistance to imatinib in nine patients in acute phase CML. All patients (3/3) with high AGP dosages (2.31+/-0.17 mg/mL; normal values, 0.5-1.3mg/mL) were primary resistant to imatinib whereas an early clinical response was observed for the six patients with normal AGP levels (1.13+/-0.2mg/mL). No mutation in the adenosine triphosphate domain of Abl were detected before the initiation of imatinib therapy. By using in vitro tests combining various imatinib concentrations (1-10 microM) with purified human AGP (1 and 3 mg/mL), we demonstrate that imatinib-induced apoptosis of K562 or fresh leukemic CML cells is abrogated or reduced. The same effect was observed using sera from donors with high AGP levels (1.9-3.28 mg/mL). In patients with CML in blastic phase, AGP levels could reflect pharmacological resistance to imatinib, suggesting that increased dosage of imatinib or the use of a competitor to drug binding should be recommended to optimize the therapeutic effect of the drug.     

红毛五加多糖对人乳腺癌细胞系MDA-MB-231增殖和核转录因子p53、c-myc蛋白表达的影响

目的 探讨红毛五加多糖（AGP）对人乳腺癌细胞系MDA-MB-231增殖以及对细胞核转录因子p53、c-myc表达的影响。方法 在DMEM培养基内加入不同浓度AGP（0.15625、0.3125、0.625、1.25、2.5 g/L）体外培养人乳腺癌细胞系MDA-MB-231 1d、3d、5d、7d后,用细胞增殖及细胞毒性检测试剂盒WST-1测定人乳腺癌细胞的增殖,倒置显微镜观察其形态变化;用免疫荧光法、免疫印迹法检测人乳腺癌细胞凋亡相关蛋白p53、c-myc的表达。 结果 WST-1法显示,不同浓度AGP作用3d、5d、7d后对人乳腺癌细胞系MDA-MB-231的增殖具有抑制作用,与阴性对照组相比差异有显著性（P ＜0.05）;抑制率与AGP剂量、作用时间呈依赖性。免疫荧光法及免疫印迹法显示,AGP作用于人乳腺癌细胞系MDA-MB-231后,其细胞的c-myc表达明显减弱,并向细胞质内聚集;而免疫印迹法显示p53表达显著增强。结论 AGP具有抑制人乳腺癌细胞系MDA-MB-231增殖的作用,这可能与AGP下调c-myc表达、上调p53表达有关。     

Recommendations for a safe restart of elective aerosol-generating oral surgery procedures following the COVID-19 pandemic outbreak: An Italian multicenter study

Among healthcare workers, oral and maxillofacial surgeons are some of the most exposed to coronavirus disease (COVID-19). The aim of this retrospective study was to develop suggestions for continuing the work of oral and maxillofacial surgeons using a safe protocol for elective and urgent aerosol-generating procedures that could prevent the onset of new clusters.Based on the results obtained and a guidelines review of those Asian countries that had promptly managed the current pandemic, the following safety protocol was developed:     

红毛五加多糖对体外人胃癌细胞抑制作用特点

采用集落形成和ＭＴＴ法研究红毛五加多糖抑癌作用特点,志五加多糖明显抑制胃癌干细胞集落形成,并选择性抑制该细胞的活性和功能状态,而对正常细胞影响甚微,提示红毛五加多糖用于癌症的防治可能较为安全和有效。     

Taking a Toll on human disease: Toll-like receptor 4 agonists as vaccine adjuvants and monotherapeutic agents

Toll-like receptor (TLR) agonists are being developed for use as vaccine adjuvants and as stand-alone immunomodulators because of their ability to stimulate innate and adaptive immune responses. Among the most thoroughly studied TLR agonists are the lipid A molecules that target the TLR4 complex. One promising candidate, monophosphoryl lipid A, which is a derivative of lipid A from Salmonella minnesota, has proven to be safe and effective as a vaccine adjuvant in > 120,000 human doses. A new class of synthetic lipid A mimetics, the aminoalkyl glucosaminide 4-phosphates (AGPs), have been engineered specifically to target human TLR4 and are showing promise as vaccine adjuvants and as monotherapeutic agents capable of eliciting nonspecific protection against a wide range of infectious pathogens. In this review, the authors provide an update of the preclinical and clinical experiences with the TLR4 agonists, MPL^® (Corixa Corporation) adjuvant and the AGPs.