氯霉素人工抗原的合成与鉴定

采用重氮化法和碳二亚胺(EDC)法合成了氯霉素人工抗原.经紫外光谱法、电泳鉴定表明偶联成功;采用三硝基苯磺酸法测得载体蛋白ε-NH3+残基利用率分别为31.02%、22.27%,偶联物的结合比为18.9、13.6;制备的抗原分别免疫小白鼠获得多克隆抗体,血清效价可达10-6以上.经比较,碳二亚胺法更适于氯霉素人工抗原的制备.     

羊奶粉中氯霉素类药物残留液相色谱-串联质谱法的研究

[目的]研究羊奶粉中氯霉素、甲砜霉素、氟甲砜霉素残留的液相色谱-串联质谱测定方法。[方法]样品经乙腈提取,固相萃取柱净化,以甲醇水作为流动相,采用多反应监测负离子模式进行定性及内标法定量分析。[结果]氯霉素、甲砜霉素、氟甲砜霉素的相关系数均大于0.999,氯霉素检出限为0.1μg/kg,甲砜霉素和氟甲砜霉素检出限为0.2μg/kg;氯霉素加标回收率为100.9%～116.2%,甲砜霉素加标回收率为88.4%～99.6%,氟甲砜霉素加标回收率为89.6%～103.2%。[结论]该方法灵敏度高、准确性好,适于测定羊奶粉中氯霉素、甲砜霉素,氟甲砜霉素的残留量。     

抗氯霉素单克隆抗体的制备及其化学发光酶免疫法的建立

以人工合成的氯霉素-牛血清白蛋白(CAP-HS-BSA)免疫Balb/c小鼠,应用杂交瘤技术获得了一株分泌抗氯霉素单克隆抗体(CAP-McAb)的杂交瘤细胞5D7,并对其进行效价、亲和力和特异性测定。结果显示,其分泌的抗体亚类为IgG1,间接ELISA检测细胞培养上清效价为1∶512,诱生的腹水经纯化后效价为1∶2×105,亲和常数为3.6×108L/mol;应用上述单抗建立的检测氯霉素的化学发光酶免疫分析法(ci-CLIA),其检测范围为0.001μg/L~10μg/L,检出限达0.0025μg/L,IC50为39.6μg/L,且与L-苯丙氨酸、L-酪氨酸、青霉素、四环素、庆大霉素等的交叉反应率均小于0.01%,可满足我国对水产品中氯霉素残留检测的要求。     

Review of some pharmacokinetic and pharmacodynamic properties of anti‐infective medicines administered to the koala (Phascolarctos cinereus)

Although koalas are iconic Australian animals, no pharmacokinetic studies of any first‐line medicines used to treat diseased or injured koalas had been published prior to 2010. Traditionally, medicine dosages suggested for this species underwent linear extrapolation from those recommended for domesticated species. The koala, a specialist folivore whose natural diet consists of almost exclusively Eucalyptus spp. foliage has anatomical and physiological adaptations for detoxifying their diet which also affect medicine pharmacokinetic profiles. This review addresses aspects of medicine absorption, clearance, and other indices (such as medicine binding to plasma proteins) of enrofloxacin/marbofloxacin and chloramphenicol used for the systemic treatment of chlamydiosis, and fluconazole ± amphotericin, and posaconazole for the treatment of cryptococcosis. Based on observations from published studies, this review includes suggestions to improve therapeutic outcomes when administering medicines to diseased koalas.     

氯霉素与4-乙烯基吡啶分子印迹体系的理论优化与制备

以氯霉素(CAP)为印迹分子,4-乙烯基吡啶(4-Vpy)为功能单体,分别以乙二醇二甲基丙烯酸酯(EGDMA)、季戊四醇三丙烯酸酯(PETA)和三羟甲基丙烷三甲基丙烯酸酯(TRIM)为交联剂,采用密度泛函数理论(DFT)的ωB97XD/6-31G(d,p)方法,模拟了CAP与4-Vpy的相互作用,探讨二者在不同摩尔反应比例时形成稳定复合物的空间构型并确定了最佳摩尔反应比例;依据交联剂分别与印迹分子、功能单体间的结合能优化了交联剂。计算结果表明:CAP与4-Vpy摩尔反应比为1∶4时,以PETA为交联剂时形成的有序复合物氢键数目最多,复合物构型最稳定。Scatchard分析结果表明,在研究浓度范围内CAP-MIPs对CAP仅存在一种结合位点,最大表观吸附量为73.97 mg/g。     

鸡蛋中氯霉素残留的检测方法及其消除规律

选用处于产蛋高峰期的健康海兰蛋鸡20只,单笼饲养,多剂量内服氯霉素(每千克体质量100 mg,连喂12 d),停药后逐只逐日收集鸡蛋,将蛋白、蛋黄分别匀浆,用乙腈、乙酸乙酯、正己烷萃取及净化后,HPLC检测氯霉素浓度.色谱柱为Waters Nova-Pak C18(3.9 mm×150 mm)柱,检测波长为280 nm,流动相为乙腈/水(20/80),流速为1 mL/min,进样量为50 μL.在上述条件下,氯霉素的色谱峰保留时间约为8.0 min,最低检测限为0.002 μg/g,标准曲线的线性范围为0.002～20 μg/g.氯霉素含量为0.5 μg/g时,在蛋白中的批内、批间变异系数分别为3.52%、3.43%;在蛋黄中的批内、批间变异系数分别为3.83%、3.37%.将氯霉素以0.5 μg/g分别添加到空白蛋白和蛋黄中,测得蛋白、蛋黄中氯霉素的回收率分别为94.89%、83.15%.结果表明,本法是一种简便、灵敏、可靠的检测鸡蛋中氯霉素残留的分析方法.停药当天,蛋白、蛋黄中的氯霉素分别为3.61、14.51 μg/g;停药第5天,分别为0.05、7.17 μg/g;停药第8天,蛋白中已检测不到氯霉素,蛋黄中氯霉素为0.80 μg/g;停药第11天,蛋黄中尚有0.04 μg/g的氯霉素,而停药第12天,蛋黄中已检测不到氯霉素.采用MCPKP药动学参数计算程序处理药时数据,算出蛋白、蛋黄中的消除半衰期分别为0.75、1.64 d.结果表明,氯霉素多分布于蛋黄,在蛋黄中的残留水平高,且在蛋黄中的消除较蛋白缓慢.     

氟苯尼考对鸡多杀性巴氏杆菌感染的疗效试验

以试管肉汤两倍稀释法测定氟苯尼考和氯霉素对鸡多杀性巴氏杆菌的最小抑菌浓度，然后对实验性鸡多杀性巴杆菌感染进行内服或肌注给药3d（每天2次）的治疗试验。结果表明，氟苯尼考和氯霉素对鸡多杀性巴氏杆菌的最小抑菌浓度分别是0．5和1．0μg／mL。以20、40、80mg／kgBW氟苯尼考和40mg／kgBW氯霉素的剂量给鸡内服给药后，对鸡多杀性巴氏杆菌感染的治愈率分别为93．3％、100％、100％及70％；相同剂量肌注给药的治愈率分别为86．7％、100％、100％和83．3％，而感染对照组的死亡率为90．0％。     

Isolation and identification of fish pathogen Edwardsiella tarda from mariculture in China

The causative agent was isolated from diseased turbots (Scophthalmus maximus) stricken by a high‐mortality outbreak of bacterial septicaemia occurring in a mariculture farm in Yantai, a northern coastal city of China. Seven pure isolates, namely EH‐15, EH‐103, EH‐107, EH‐202, EH‐203, EH‐305 and EH‐306, belonged to Edwardsiella tarda. The phenotypic features of the cultures were analysed extensively. Three of the isolates showed high 16S rDNA sequence similarities with E. tarda sequence (GenBank accession no. EF467289). However, unlike the E. tarda ATCC 15947, all the isolates, except EH‐15, contained a novel large plasmid sized about 23.7 kb. Furthermore, pathogenicity of the isolates was addressed by experimental challenges with fish models. The isolates exhibited strong virulence to swordtail fish with LD₅₀ ranging between 3.8 × 10³ and 3.8 × 10⁵ CFU g^?1, and EH‐202 displaying the lowest LD₅₀ value among them. Antibiotic susceptibilities of E. tarda isolates were assayed. Compared with E. tarda ATCC 15947, the isolates displayed strong resistance to chloramphenicol, and the probable dominant chloramphenicol resistance determinant was cat III. Depicting the main biological properties of turbot‐borne E. tarda strains in China, the study provided useful information for further unveiling their pathogenic mechanisms.     

氯霉素人工抗原的合成及多克隆抗体的制备

将氯霉素以重氮化方法使之分别与牛血清白蛋白(BSA)、卵清蛋白(OVA)、人血清白蛋白(HSA)载体蛋白连接,三种偶联物选择其中两个分别作为免疫原与包被原进行抗血清制备及ELISA试验熏结果产生了特异性抗体。交叉试验表明:产生的特异性抗体与氯霉素反应明显熏与其他类似物交叉反应不明显。     

氯霉素残留的危害及其检测方法

氯霉素属广谱抗生素 ,曾在畜牧业中广为应用。但氯霉素有较强的副作用和毒性作用 ,如果氯霉素在食用动物中残留 ,可通过食物链传给人类 ,长期微量摄入氯霉素 ,不仅使人体肠道正常菌群失调 ,而且还会引起多种疾病 ,对人类的健康造成危害。世界上许多国家禁止此药用于生产食品动物 ,并规定了在畜产品中氯霉素不得检出。对于氯霉素的残留 ,存在多种检测方法 ,不同的检测方法具有不同的检出限。检测限问题已成为关注的焦点 ,发达国家对检出限的要求越来越严格