动物专用头孢喹诺的研究进展

头孢喹诺是动物专用的第4代头孢菌素类抗生素,具有广泛的抗菌和强大的杀菌作用。其抗菌活性极强,对临床分离的各种革兰氏阳性菌、革兰氏阴性菌的MIC50、MIC90值均较小;其药动学特点优良,吸收快,达峰时间短,生物利用度较高,药时曲线下面积较大,表现分布容积也很大;头孢喹诺毒性低,在动物的可食用组织中残留较少,安全性较高。国外已将该药应用于猪、牛的呼吸系统感染及牛乳房炎的治疗。为指导头孢喹诺在我国兽医临床上的合理应用,现对其抗菌活性、药动学、残留及毒性、临床应用等最新资料进行综述。     

头孢喹诺与恩诺沙星对鸡大肠杆菌的联合药敏试验

为研究头孢类药物和氟喹诺酮类药物在治疗鸡大肠杆菌的相互作用,本试验采用肉汤稀释棋盘法,用头孢喹诺和恩诺沙星对鸡大肠杆菌标准株和临床分离株进行了联合药敏试验。结果表明,两药联用对鸡大肠杆菌标准菌株FIC指数为0.5,呈现协同作用;对鸡大肠杆菌临床分离株FIC指数为0.75,呈现相加作用。     

Pharmacokinetics and ex vivo pharmacodynamics of cefquinome in porcine serum and tissue cage fluids

A tissue cage (TC) model was used to evaluate the pharmacokinetics and ex vivo pharmacodynamics of cefquinome after intravenous (IV) and intramuscular (IM) administration to piglets at 2 mg/kg bodyweight. The mean values of area under the concentration–time curve (AUC) were 21.28 (IV) and 21.37 (IM) μg h/mL for serum, and 17.40 (IV) and 16.57 (IM) μg h/mL for TC fluid (TCF), respectively. Values of maximum concentration (C_max) were 6.15 μg/mL (serum) and 1.15 μg/mL (TCF) after IM administration. The elimination half-lives (t_1/2β) in TCF (10.63 h IV and 11.81 h IM) were significantly higher than those in serum (2.33 h IV and 2.30 h IM) (P < 0.05). The values of AUC_TCF/AUC_serum (%) after IV and IM administration were 82.4% and 80.7%, respectively.The ex vivo time-kill curves were established for serum and TCF samples using Escherichia coli ATCC 25922. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration values of cefquinome against E. coli were 0.030 and 0.060 μg/mL in Mueller–Hinton broth, and 0.032 and 0.064 μg/mL in both serum and TCF, respectively. The ex vivo growth inhibition data of TCF after IM administration were fitted to the sigmoid E_max model; AUC_24h/MIC was 35.01 h for bactericidal activity and 44.28 h for virtual eradication, respectively. The findings from this study suggest that cefquinome may be therapeutically effective in diseases of pigs caused by E. coli when used at a dose rate of 1.33 mg/kg administered every 24 h for organisms with MIC₉₀ ⩽ 0.50 μg/mL.     

硫酸头孢喹肟注射液在猪体内的药代动力学及生物等效性研究

为了研究硫酸头孢喹肟注射液在猪体内的药代动力学及生物等效性,将10头健康猪随机分成两组,按2 mg/kg体重肌肉注射两种硫酸头孢喹肟注射液,采用高效液相色谱法测定血浆中硫酸头孢喹肟的浓度,计算主要药代动力学参数,评价两制剂的生物等效性.肌肉注射两种硫酸头孢喹肟注射液后两组的消除半衰期(T1/2β)、达峰浓度(Cmax)、曲线下面积(AUC)等参数差异不显著(P＞0.05).采用双单侧t检验进行判断,受试组AUC 90％置信区间为108.2％ ～ 115.3％,在对照组均值的80％～120％范围内;Cmax90％置信区间为91.9％～115.3％,在对照组均值的70％ ～130％范围内.两种产品在猪体内具有生物等效性和类似的药代动力学,为临床给药方案的制定和临床合理用药提供了参考.     

硫酸头孢喹诺混悬剂的质量检验及体外抑菌实验

对自制的硫酸头孢喹肟混悬剂进行质量检验和体外抑菌实验。按照筛选出的配方,应用分散法制备硫酸头孢喹肟混悬型制剂,检验混悬剂的质量并针对临床分离的奶牛乳房炎混合菌株进行体外抑菌实验。结果表明：制得的硫酸头孢喹肟混悬剂符合国家质量标准要求,体外抑菌实验效果明显。     

The Use of Cefquinome in Equine Semen Extender

Antibiotics are commonly used in equine semen extender for conservation, if semen has to be stored cooled for a maximum of 48 hours or frozen, to eliminate pathogenic or potentially pathogenic bacteria from semen and reduce the risk of postmating endometritis. Little is known about the effect of antibiotics on spermatozoa when semen is stored over a longer period. Cefquinome, a broad spectrum antibiotic and fourth-generation cephalosporin, has been proven to be a powerful drug for the treatment of endometritis and mastitis in different species. Recently in equine studies, it was found to localize in high concentrations in the endometrium. Therefore, cefquinome was used as the antibiotic in semen extender and compared with a commercial semen extender containing gentamicin for effects on motility and membrane integrity of spermatozoa. During the breeding season, ejaculates from nine light horse stallions were collected and half of each ejaculate was stored for 48 hours in modified Kenney type semen extender containing either cefquinome or gentamicin. At 0, 24, and 48 hours, aliquots (20 μL) of the stored semen were evaluated for (progressive) motility and membrane integrity, as well as for various motility parameters by computer assisted sperm analysis. No differences (P > .05) were found in total motility or progressive motility between extenders at any time point. However, there were differences (P < .05) in velocity parameters, although the effect of velocity parameters on fertility is not clear. In general, semen parameters after storage in non-fat dried skim milk semen extender containing cefquinome are comparable with those after storage in semen extender containing gentamicin. The wider spectrum of bactericidal activity possessed by cefquinome may prove to be beneficial in some cases.     

硫酸头孢喹肟注射液对仔猪传染性胸膜肺炎的临床疗效试验

将硫酸头孢喹肟注射液分为高、中、低(4、2、1mg/kg体重)3个剂量组分别肌肉注射治疗仔猪传染性胸膜肺炎,同时设头孢噻呋冻干粉对照组,按3 mg/kg体重给药,一日一次,连用3天。结果表明,硫酸头孢喹肟注射液3个剂量组和阳性对照组(头孢噻呋冻干粉对照组)对仔猪传染性胸膜肺炎均有明显的治疗效果,有效率及相对增重率显著高于阴性对照组(P＜0.01);硫酸头孢喹肟注射液高、中剂量组的有效率及相对增重率显著高于硫酸头孢喹肟注射液低剂量组和阳性对照组((P＜0.01)。人工感染治疗试验结果表明硫酸头孢喹肟注射液按每1kg体重2mg肌注,一日一次,连用3天,对仔猪传染性胸膜肺炎有良好的治疗效果。     

HPLC法测定硫酸头孢喹肟冻干粉针中硫酸头孢喹肟含量

建立高效液相色谱法(HPLC法)测定硫酸头孢喹肟冻干粉针中硫酸头孢喹肟的含量。色谱条件为色谱柱Kromasil C18柱(250 mm×4.6 mm,5μm),以高氯酸钠-磷酸-三乙胺缓冲液(pH3.6):乙腈(体积比90∶10)为流动相,流速为0.8 mL/min,紫外检测波长为254 nm。结果表明,硫酸头孢喹肟在0.05~25μg/mL范围内呈良好的线性关系,r=0.99 96,平均回收率为100.34%(n=9),RSD为1.34%。该方法简便快速,结果准确可靠,可用于硫酸头孢喹肟冻干粉的质量控制研究。     

Effect of ketoprofen co-administration on pharmacokinetics of cefquinome following repeated administration in goats

The pharmacokinetics of cefquinome (2 mg/kg every 24 hr for 5 days) was determined following intramuscular administration alone and co-administration with ketoprofen (3 mg/kg every 24 hr for 5 days) in goats. Six goats were used for the study. In the study, the crossover pharmacokinetics design with 20-day washout period was performed in two periods. Plasma concentrations of cefquinome were assayed using high-performance liquid chromatography by ultraviolet detection. The mean terminal elimination half-life (t_1/2ʎz), area under the concentration–time curve (AUC_0–24), peak concentration (C_max), apparent volume of distribution (V_darea/F), and total body clearance (CL/F) of cefquinome after the administration alone were 4.85 hr, 11.06 hr*µg/ml, 2.37 µg/mL, 1.23 L/kg, and 0.17 L/h/kg after the first dose, and 5.88 hr, 17.01 hr*µg/mL, 3.04 µg/mL, 0.95 L/kg, and 0.11 L/h/kg after the last dose. Ketoprofen significantly prolonged t_1/2ʎz of cefquinome, increased AUC_0–24 and C_max, and decreased V_darea/F and CL/F. Cefquinome exhibited low accumulation after the administration alone and in combination with ketoprofen. These results indicated that ketoprofen prolonged the elimination of cefquinome in goats. The 24-hr dosing intervals at 2 mg/kg dose of cefquinome, which co-administered with ketoprofen, may maintain T> minimum inhibitory concentration (MIC) values above 40% in the treatment of infections caused by susceptible pathogens with the MIC value of ≤0.75 μg/ml in goats with an inflammatory condition.     

硫酸头孢喹肟注射液在猪体内的生物等效性研究

为研究国产和进口硫酸头孢喹肟注射液(7.5%)在猪体内的药代动力学特征和生物等效性,采用双处理、双周期随机交叉试验设计,将20头健康三元杂交猪随机分成2组,按3mg/kg体重分别单剂量肌内注射受试制剂和参比制剂。采用超高效液相色谱-串联质谱法测定血浆中头孢喹肟的浓度,利用Win Nonlin6.3软件计算主要药动学参数,并评价两种制剂的生物等效性。结果显示,受试制剂和参比制剂的Tmax分别为2.30±0.73h和2.25±0.55h;Cmax分别为2.37±0.34μg/mL和2.45±0.36μg/mL;AUC0-t分别为26.38±2.30μg·h·mL^-1和24.86±2.19μg·h·mL^-1;AUC0-∞分别为26.74±2.34μg·h·mL^-1和25.07±2.20μg·h·mL^-1。硫酸头孢喹肟注射液受试制剂和参比制剂的AUC0-t、AUC0-∞、Cmax、Tmax均无显著性差异(P>0.05)。双单侧t检验结果显示两种制剂生物等效,临床上可相互替代。该试验可为兽医临床合理用药提供参考。