洛美沙星对实验性鸡葡萄球菌病的药效研究

为了探讨国内新近研制的氟喹诺酮类长半减期药物洛美沙星（Ｌｏｍｅｆｌｏｘａｃｉｎ）对鸡葡萄球菌病的疗效进行了本研究。以试管２倍稀释法测定洛美沙星及对照药对金黄色葡萄球菌的最小抑菌浓度,然后用洛美沙星、环丙沙星、恩诺沙星进行饮水给药５ｄ的疗效试验。结果表明,洛美沙星、环丙沙星、恩诺沙星、诺氟沙星、红霉素对鸡金黄色葡萄球菌Ｃ５６０１１株的最小抑菌浓度分别为１．０、０．１２５、０．２５、１．０、３２ｍｇ／Ｌ。２５、５０、１００ｍｇ／Ｌ洛美沙星饮水给药对鸡葡萄球菌病的治愈率分别为６６．７％、８０％、７６．７％,有效率分别为９０％、９６．７％、９６．７％。５０ｍｇ／Ｌ环丙沙星、恩诺沙星的治愈率则分别为７６．７％、８０％,有效率分别为９３．３％、９６．７％。５０、１００ｍｇ／Ｌ洛美沙星及５０ｍｇ／Ｌ恩诺沙星３个饮水给药组鸡的增重显著高于感染对照组。     

Pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin in freshwater crocodiles (Crocodylus siamensis) after intravenous and intramuscular administration

To the best of the authors’ knowledge, pharmacokinetic information to establish suitable therapeutic plans for freshwater crocodiles is limited. Therefore, the purpose of this study was to clarify the pharmacokinetic characteristics of enrofloxacin (ENR) in freshwater crocodiles, Crocodylus siamensis, following single intravenous and intramuscular administration at a dosage of 5 mg/kg body weight (b.w.). Blood samples were collected at assigned times up to 168 hr. The plasma concentrations of ENR and its metabolite ciprofloxacin (CIP) were measured by liquid chromatography tandem–mass spectrometry. The concentrations of ENR and CIP in the plasma were quantified up to 144 hr after both the administrations. The half-life was long (43–44 hr) and similar after both administrations. The absolute i.m. bioavailability was 82.65% and the binding percentage of ENR to plasma protein ranged from 9% to 18% with an average of 10.6%. Percentage of CIP (plasma concentrations) was 15.9% and 19.9% after i.v. and i.m. administration, respectively. Based on the pharmacokinetic data, susceptibility break point and PK-PD indexes, i.m. single administration of ENR at a dosage of 5 mg/kg b.w. might be appropriate for treatment of susceptible bacteria (MIC > 1 μg/mL) in freshwater crocodiles, C. siamensis.     

Pharmacokinetics and tissue distribution of enrofloxacin after single intramuscular injection in Pacific white shrimp

The pharmacokinetic properties and tissue distribution of enrofloxacin (EF) were investigated after single intramuscular (i.m.) dose of 10 mg/kg body weight (b.w.) in Pacific white shrimp at 22 to 25°C. EF and its metabolite ciprofloxacin (CF) were determined by high‐performance liquid chromatography. After i.m. administration, EF was absorbed quickly, and the peak of EF concentration (C_max) reached at first time point in hemolymph. The volume of distribution V_d(area) of EF was 3.84 L/kg, indicating that the distribution of EF was good. The area under the concentration–time curve (AUC) of EF was 90.1 and 274.2 μg hr/ml in muscle and hepatopancreas, respectively, which was higher than 75.8 μg hr/ml in hemolymph. The EF elimination was slow in muscle and hepatopancreas with the half‐life (T_1/2β) of 52.3 and 75.8 hr, respectively. CF, the mainly metabolite of EF, was detected in hemolymph, muscle and hepatopancreas. The C_max was 0.030, 0.013 and 0.218 μg/ml, respectively. Based on a minimum inhibitory concentration (MIC) of 0.006–0.032 μg/ml for susceptible strains, EF i.m. injected at a dose 10 mg/kg could be efficacious against common pathogenic bacteria of Pacific white shrimp.     

盐酸环丙沙星不同给药途径对牛胃肠炎的疗效观察

将收治的胃肠炎病牛随机分为4组,用盐酸环丙沙星分别按口服、瓣胃注射、肌肉注射、静脉注射的方法进行治疗.结果表明,经瓣胃注射方法投药对牛胃肠炎治愈效果好,对病牛瘤胃纤毛虫数量、活力影响小,而且有效克服了其他给药途径引起的弊端,具有推广应用价值.     

大肠杆菌对环丙沙星和恩诺沙星的敏感性恢复

为给制定临床使用抗菌药物的轮换用药方案,降低耐药性的危害提供科学依据,采用单因素试验和正交试验方法,研究不同细菌传代、营养因素和耐药菌下大肠杆菌耐药菌株D600对环丙沙星、恩诺沙星耐药水平的影响。结果表明:D600经210代传代,对环丙沙星的最小抑菌浓度(MIC)由128μg/mL(高度耐药)降至32μg/mL(中度耐药),而对恩诺沙星的MIC值没有变化;在稀释32倍的LB肉汤培养基中传代,D600对环丙沙星、恩诺沙星的MIC值由≥128μg/mL(高度耐药)分别降至0.25μg/mL和1μg/mL(敏感)。营养因素水平越低、传代次数越多、耐药菌比例越小,D600对药物的MIC值越小,直至恢复到敏感。且上述因子对环丙沙星敏感性恢复的作用强于恩诺沙星。     

内服盐酸环丙沙星糊剂治疗仔猪黄白痢的研究

应用盐酸环丙沙星糊剂,按盐酸环丙沙星１０ｍｇ／ｋｇ口服,每日２次,３ｄ为一疗程,对仔猪黄痢和白痢进行治疗研究,并和痢特灵治疗效果进行比较。结果发现：盐酸环丙沙星糊剂治疗组的治愈率为９２．９％,好转率为５．２％,无效率为１．８％．治愈率比痢特灵治疗组高４５个百分点,而无效率比痢特灵治疗组低２９．４个百分点。试验结果表明：盐酸环丙沙星糊剂治疗仔猪黄痢和白痢效果显著,可在生产实践中推广应用。     

盐酸环丙沙星在奶牛患子宫内膜炎时乳汁中的药动学及残留

研究通过子宫内灌注盐酸环丙沙星,采用内标法以反相高效液相色谱法测定了4头患子宫内膜炎的奶牛乳汁中盐酸环丙沙星的药物浓度,用MCPKP房室分析程序处理乳中药物浓度-时间数据。研究表明,患牛子宫内给药的血样药时数据经MCPKP处理符合一级吸收一室开放模型。乳样中主要药动学参数为:Ka为0.091 25 h-1,tmax为19.17 h,Cmax为0.018 25 靏mL-1,AUC为1.032 mg(Lh)-1,T1/2Ka为8.25 h,T1/2K为24.64 h。弃奶期为4 d。     

磺胺二甲基嘧啶与环丙沙星对小麦种子萌发和幼苗生长的影响

为研究抗生素胁迫对小麦种子萌发和幼苗生长发育的影响,选取磺胺二甲基嘧啶（Sulfadimidine,SM2）和环丙沙星（Ciprofloxacin,CIP）两种典型抗生素为研究对象,采用水培方法,通过测定不同浓度的两种抗生素对小麦种子芽和根的生长抑制率、幼苗生物量、根系形态和根系活力指标,分析比较了两种抗生素对小麦种子和幼苗的生态毒性差异。结果表明： 0.1~2.0 mg·L^-1的SM2和0.1~1.0 mg·L^-1的CIP能够促进小麦种子根和芽的生长,当SM2浓度达到10.0 mg·L^-1、CIP浓度达到5.0 mg·L^-1时,两种抗生素开始对小麦种子根长产生抑制作用,并且随着浓度的增大抑制作用显著增强;两种抗生素对作物种子根长的抑制效应强于芽长; 0.1 mg·L^-1的SM2促进小麦幼苗生长以及干物质积累,但随着SM2浓度增大,小麦幼苗生长受到抑制,根系生物量以及根系性状（总根长、平均直径）显著降低; CIP对小麦幼苗生长、干物质积累和根系性状均具有抑制作用,并且随着CIP浓度的增大抑制作用增强; SM2和CIP均抑制小麦根系活力,随着抗生素浓度的升高小麦根系氧化还原力降低,根系活力逐渐减弱。研究表明,SM2和CIP会在小麦根系不断积累,影响小麦正常生长,CIP对小麦幼苗生态毒性相对更强,0.1 mg·L^-1CIP即会抑制小麦幼苗生长。     

环丙沙星单克隆抗体的制备及其免疫学特性鉴定

用EDC法将BSA和OVA分别和环丙沙星（Ciprofloxacin, CIP）偶联作为免疫原和包被原,并经紫外扫描 (UV Scan)、聚丙烯酰胺凝胶电泳（SDS-PAGE）鉴定。用合成的BSA-CIP免疫BALB/c小鼠,经过3次免疫后,用间接ELISA和阻断ELISA选择细胞融合备用鼠,选择高效价、敏感的小鼠进行抗原超强免疫;取其脾细胞应用杂交瘤技术与骨髓瘤细胞建立分泌CIP单克隆抗体的杂交瘤细胞株;用体内诱生腹水法制备CIP mAb,对CIP mAb的效价、敏感性和特异性等免疫学特性进行鉴定。聚丙烯酰胺凝胶电泳鉴定表明BSA-CIP人工抗原偶联成功;免疫的3只小鼠血清抗体效价均达到10-4;其中2号小鼠血清CIP抑制效价较高且IC50最低,达48.59μg/L,融合后筛选出Z3G12B3和Z2H8C10两株敏感特异的杂交瘤细胞,其两株细胞培养上清液效价为1:512,腹水效价为1:2.56×105,Z3G12B3株对CIP的IC50为2.47μg/L,与二氟沙星、沙拉沙星有小于0.03％的交叉反应性,与其他抑制物无交叉反应性。本试验获得了高效价、敏感、特异的抗CIP mAb,为CIP残留ELISA检测试剂盒和试纸条的建立奠定了坚实的基础。