毛细管电泳法快速分离和检测肠毒性大肠杆菌

 建立了快速分离和检测引起仔猪腹泻的肠毒性大肠杆菌K88、K99和 987P细菌细胞的毛细管区带电泳方法 ,并进行了腹泻仔猪粪便中肠毒性大肠杆菌的应用检测分析。结果表明 ,在电泳缓冲液为 0 0 5mol/LNa2 CO3 NaHCO3(pH 9 9)、分离电压为 1 4 1kV、检测波长为 2 1 0nm的电泳条件下 ,E coliK88、K99和 987P的细胞分别具有单一、稳定的特征谱峰 ,其保留时间的相对标准偏差RSD≤ 0 9% ;在确定的实验条件下 ,实现了腹泻仔猪粪便中肠毒性大肠杆菌的快速检测分析 ,发现将出生 5d～ 6d的腹泻仔猪粪便引入培养基中增殖后主要检出K88。     

甘草锌佐治小儿感染性腹泻122例临床疗效观察

用甘草锌佐治小儿感染性腹泻１２２例治疗率为９０．１％，疗效较满意。     

In Silico Prediction,Molecular Docking and Dynamics Studies of Steroidal Alkaloids of Holarrhena pubescens Wall. ex G. Don to Guanylyl Cyclase C: Implications in Designing of Novel Antidiarrheal Therapeutic Strategies

The binding of heat stable enterotoxin (STa) secreted by enterotoxigenic Escherichia coli (ETEC) to the extracellular domain of guanylyl cyclase c (ECD_GC-C) causes activation of a signaling cascade, which ultimately results in watery diarrhea. We carried out this study with the objective of finding ligands that would interfere with the binding of STa on ECD_GC-C. With this view in mind, we tested the biological activity of a alkaloid rich fraction of Holarrhena pubescens against ETEC under in vitro conditions. Since this fraction showed significant antibacterial activity against ETEC, we decided to test the screen binding affinity of nine compounds of steroidal alkaloid type from Holarrhena pubescens against extracellular domain (ECD) by molecular docking and identified three compounds with significant binding energy. Molecular dynamics simulations were performed for all the three lead compounds to establish the stability of their interaction with the target protein. Pharmacokinetics and toxicity profiling of these leads demonstrated that they possessed good drug-like properties. Furthermore, the ability of these leads to inhibit the binding of STa to ECD was evaluated. This was first done by identifying amino acid residues of ECD_GC-C binding to STa by protein–protein docking. The results were matched with our molecular docking results. We report here that holadysenterine, one of the lead compounds that showed a strong affinity for the amino acid residues on ECD_GC-C, also binds to STa. This suggests that holadysenterine has the potential to inhibit binding of STa on ECD and can be considered for future study, involving its validation through in vitro assays and animal model studies.     

蒙药野罂粟对腹泻大鼠脏器AC、cAMP、cGMP含量影响的实验研究

本文研究野罂粟对实验动物脏器中腺苷酸环化酶（AC）、环磷酸腺苷（cAMP）、环磷酸鸟苷（cGMP）含量的影响,探讨野罂粟作用的脏器归属.采用双抗体夹心酶联免疫吸附法（ELISA）测定各脏器组织中AC、cAMP、cGMP含量.与模型组比较,野罂粟降低大鼠心内AC含量,升高脾、大肠、小肠内AC含量;降低大肠内cAMP含量,升高胃内cAMP含量;降低肺内cGMP含量,升高大肠、脑内cGMP含量;降低大肠内cAMP/cGMP比值.结果发现野罂粟作用后,胃、肺、大肠内环核苷酸浓度变化显著.     

Affinity capillary electrophoresis for the assessment of binding affinity of carbohydrate‐based cholera toxin inhibitors

Developing tools for the study of protein carbohydrate interactions is an important goal in glycobiology. Cholera toxin inhibition is an interesting target in this context, as its inhibition may help to fight against cholera. For the study of novel ligands an affinity capillary electrophoresis (ACE) method was optimized and applied. The method uses unlabeled cholera toxin B‐subunit (CTB) and unlabeled carbohydrate ligands based on ganglioside GM1‐oligosaccharides (GM1os). In an optimized method at pH 4, adsorption of the protein to the capillary walls was prevented by a polybrene‐dextran sulfate‐polybrene coating. Different concentrations of the ligands were added to the BGE. CTB binding was observed by a mobility shift that could be used for dissociation constant (K_d) determination. The K_d values of two GM1 derivatives differed by close to an order of magnitude (600 ± 20 nM and 90 ± 50 nM) which was in good agreement with the differences in their reported nanomolar IC₅₀ values of an ELISA‐type assay. Moreover, the selectivity of GM1os towards CTB was demonstrated using Influenza hemagglutinin (H5) as a binding competitor. The developed method can be an important platform for preclinical development of drugs targeting pathogen‐induced secretory diarrhea.     

Rapid determination of rifaximin in rat serum and urine by direct injection on to a shielded hydrophobic stationary phase by HPLC

A simple and rapid reversed‐phase HPLC method for determination of rifaximin in rat serum and urine was developed. Separation of rifaximin from biological matrix was achieved by direct injection of rat serum and urine onto a restricted‐access medium, Supelco LC‐Hisep, a shielded hydrophobic stationary phase, using acetonitrile:water:acetic acid (18:82:0.1 v/v/v) as a mobile phase. The linear range was 0.10–20 µg/mL (r² > 0.999, n = 6), intraday and interday variation was <6.10%. The limits of detection and quantification were 0.03 (signal‐to‐noise ratio >3) and 0.10 µg/mL (signal‐to‐noise ratio >10), respectively. The method was successfully applied to pharmacokinetic studies of rifaximin after an oral administration to rats. Copyright © 2008 John Wiley & Sons, Ltd.     

快速检测腹泻患儿粪便中的轮状病毒抗原分析

目的:探讨粪便中轮状病毒对临床诊断的价值。方法:用单克隆抗体即金标免疫层析法,检测分析腹泻患儿粪便中的轮状病毒抗原。结果:表明检测粪便中轮状病毒是诊断轮状病毒肠炎敏感的方法。结论:粪便中轮状病毒抗原的检测,对临床诊断轮状病毒肠炎提供了依据。     

加味胃关煎治疗脾虚寒湿型泄泻

目的介绍加味胃关煎治疗脾虚寒湿型泄泻经验。方法整理脾虚寒湿型泄泻的证候特点并分析其病机要点,阐释加味胃关煎的组方特点并用病案举例说明,概括加味胃关煎治疗脾虚寒湿型泄泻经验的认识。结果加味胃关煎治疗脾虚寒湿型泄泻既有理论支持,也有临床验证。结论加味胃关煎具有健脾渗湿、温肾涩肠兼散寒止痛之功,特别适用于治疗脾虚寒湿型泄泻。     

动物激生态制剂发展概况及应用

本文对1980年以来国内动物微生态制剂的发展和应用进行了报道.始于七十年代后期的动物微生态学发展迅速,为研制和应用微生态制剂提供了科学的依据.十几年间国内对禽畜肠道内的菌群比例与腹泻的关系进行了研究,相继开发出多种微生态制剂应用于畜禽肠道细菌性疾病的防治,以其疗效高、疗效短、增重快起到了抗生素无可比拟的作用,开辟了人类控制畜禽疾病的又一新途径——生态防治.     

高寒地区腹泻犊牛的血气与血液细胞分析

目的:探讨动物腹泻时血液生理生化指标的变化,为临床诊断提供依据.方法:运用i-STAT血气分析仪,测定了15例腹泻犊牛血液pH、Hb、TCO2、PCO2、PO2、HCO3-、SO2、BEecf、HcT、血液细胞的MCH、MCHC、RDW、WBC、LYM、MID、GRN、RBC、HGB、HcT、MCV和电解质Na+、K+指标.结果:腹泻犊牛的PCO2、HcT、SO2、MCHC、HGB、WBC(P<0.01)、MID(P<0.01)、HcT、MCV显著高于健康牛;而MCH、GRN、RBC也都低于健康奶牛.结论:犊牛腹泻时其血液细胞成分和血气指标发生显著的变化.