Dexamethasone and clenbuterol detection by enzyme immunoassay in Bovine Liver Tissue: A new multiresidue extraction procedure

A fast and simple extraction procedure was developed for simultaneous determination in bovine liver of two veterinary drugs, widely used as growth promoters in meat production: dexamethasone (a synthetic corticosteroid drug) and clenbuterol (a beta2‐adrenergic agonist drug). Liver samples were extracted by acetonitrile, without any clean‐up step. Two different ELISAs, specific for the two classes of drugs, were used to determine the residue concentration in the extracts. The intra‐ and inter‐extraction variability was determined at different concentrations: the intra‐extraction coefficients of variation (CVs) were between 2.5 and 17.7% for dexamethasone and between 0.9 and 9.8% for clenbuterol; the inter‐extraction CVs were between 2.0 and 16.8% for dexamethasone and between 0.5 and 10.8% for clenbuterol. Recovery ranged from 92 to 154% for dexamethasone and from 78 to 105% for clenbuterol. The limit of detection was 1.43 ng g^?1 and 0.43 ng g^?1, respectively. The limit of quantification for dexamethasone was 2.09 ng g^?1 and for clenbuterol was 0.72 ng g^?1. The combination of the new extraction procedure with an ELISA detection permitted the rapid semi‐quantitative determination of both dexamethasone at its maximum residue level (MRL: 2.5 ng g^?1 in liver tissue), and clenbuterol at low concentration level.     

盐酸克仑特罗对小鼠胚胎体外发育的影响

目的:探讨盐酸克仑特罗对小鼠1-细胞胚胎和2-细胞胚胎体外发育的影响。方法:获取小鼠1-细胞和2-细胞胚胎,分别与盐酸克仑特罗10 ng/mL,3 ng/mL和1 ng/mL的3个剂量组共培养,观察胚胎各阶段的发育情况并计算胚胎的发育率。结果:1ng/mL和3ng/mL组的1-细胞小鼠胚胎,从4-细胞期到囊胚阶段的发育率与对照组相比差异显著(P<0.05),3 ng/mL组显现出比1ng/mL组更强的抑制作用(P<0.01),10 ng/mL组,2-细胞期就与对照组有差异(P<0.05,其中 4-细胞至囊胚阶段P<0.01),囊胚率只有2.4％。10 g/mL组及3 ng/mL组的2-细胞小鼠胚胎,分别从4-细胞期和8-细胞期与对照组相比差异显著(P<0.05),1 ng/mL组的各个阶段胚胎发育率与对照组相比未见统计学差异(P>0.05)。培养液中含有盐酸克仑特罗使胚胎的粗颗粒增多,部分印裂球碎裂、退化。结论:盐酸克仑特罗对小鼠胚胎的体外发育有毒性作用并呈一定的剂量效应。盐酸克仑特罗使1-细胞小鼠胚胎被抑制在2-细胞期,对处于晚2-细胞期胚胎的影响明显降低。     

克仑特罗的急性毒性作用

目的:观察克仑特罗 (瘦肉精) 的急性毒性作用.方法:新西兰兔灌胃(ig)中毒剂量的盐酸克仑特罗溶液(150 μg·kg-1),记录心电图(ECG)II导联及V5导联;测定肌钙蛋白I (cTnI)及其他血液生化指标;对心、肝、肾进行病理组织学检查. 结果:克仑特罗能使心电图(ECG)II导联及V5导联T波显著降低,药后6 h肌钙蛋白I(cTnI)升高,对其他生化指标也有明显影响.可引起心、肝、肾发生病理学改变. 结论:克仑特罗(单剂量150 μg·kg-1,ig)能明显改变兔血清某些生化指标,对心、肝、肾功能均有一定程度的损伤.本试验为临床提供实验依据.     

氨溴特罗联合阿奇霉素治疗70例小儿支原体肺炎的疗效评价

目的 评价氨溴特罗联合阿奇霉素治疗支原体肺炎患儿的疗效.方法 支原体肺炎患儿140例,分为观察组和对照组.对照组采用阿奇霉素治疗,观察组采用阿奇霉素联合氨溴特罗治疗.结果 观察组总有效率为95.71%高于对照组85.71%,差异有统计学意义(P<0.05).两组支原体肺炎患儿均未见严重不良反应事件.结论 氨溴特罗联合阿奇霉素治疗支原体肺炎患儿疗效可靠.     

HPLC法测定氨溴特罗口服液中两组分的含量和有关物质

目的:用HPLC法测定氨溴特罗口服液中盐酸克仑特罗和盐酸氨溴索的含量及其有关物质。方法:用Zorbax SB-C18色谱柱(250 mm×4.6 mm,5μm);乙腈-0.05 moL·L-1磷酸二氢钾(含0.2％三乙胺,用磷酸调节pH至3.5)(19:81)为流动相;流速:1.0 mL·min-1;检测波长:245 nm;柱温:30℃;进样量:20μL。结果:盐酸克仑特罗与盐酸氨溴索分别与其相邻杂质峰能完全分离,盐酸克仑特罗在0.1266-506.4μg·mL-1和盐酸氨溴索在1.02-510 μg·mL-1浓度范围内线性关系均良好(r=0.9999)。结论:该法简便、准确、专属性好,可以用于氨溴特罗口服液中盐酸克仑特罗和盐酸氨溴索的含量测定及有关物质检查。     

氨溴特罗辅助治疗毛细支气管炎疗效观察

目的:观察氨溴特罗辅助治疗毛细支气管炎临床疗效.方法:对88例毛细支气管炎的患儿随机分为两组,两组患儿均采用抗感染、止咳、吸痰、雾化等常规治疗,治疗组加用氨溴特罗,观察比较两组疗效.结果:治疗组在咳嗽、咳痰、喘息、肺部哮鸣音、肺部湿口罗音等的消失时间和总治疗时间等方面均短于对照组,差异有统计学意义(P＜0.01),未见明显不良反应发生.结论:氨溴特罗辅助治疗毛细支气管炎安全、有效.     

固相萃取-气质联用法分析肉食品中盐酸克伦特罗残留量

[目的]建立固相萃取-气质联用法测定肉食品中盐酸克伦特罗残留量的方法。[方法]样品经乙醚萃取，LC-WCX离子交换柱分离纯化，氨化甲醇溶液洗脱浓缩，与BSTFA衍生后进行GC／MS分析。[结果]建立的方法在所测范围内呈良好的线性关系，相关系数0．9989，检测限达1．5μg／kg，相对标准偏差在4.2％～10．3％，样品的加标回收率在78．5％～92．6%。[结论]该方法灵敏、定量准确，可广泛应用于肉食品中盐酸克伦特罗残留量的检测。     

Single‐dose administration of clenbuterol is detectable in dried blood spots

Clenbuterol is a β₂‐agonist prescribed for asthmatic patients in some countries. Based on its anabolic and lipolytic effects observed in studies on rodents and in livestock destined for food production, clenbuterol is abused by bodybuilders and athletes seeking leanness. Urinary clenbuterol analysis is part of routine doping analysis. However, the collection of urine samples is time‐consuming and can be intimidating for athletes. Dried blood spot (DBS) appears attractive as an alternative matrix, but the detectability of clenbuterol in humans through DBS has not been investigated. This study evaluated if clenbuterol could be detected in DBS and urine collected from six healthy men after oral intake of 80 μg clenbuterol. The DBS and urine samples were collected at 0, 3, 8, 24, and 72 h post‐ingestion, with additional urine collections on days 7 and 10. Using LC–MS/MS, it was shown that clenbuterol could be detected in all DBS samples for 24 h post‐ingestion and with 50% sensitivity 3 days after ingestion. The DBS method was 100% specific. Evaluation of analyte stability showed that clenbuterol is stable in DBS for at least 365 days at room temperature when using desiccant and avoiding light exposure. In urine, clenbuterol was detectable for at least 7–10 days after ingestion. Urinary clenbuterol concentrations below 5 ng/mL were present in some subjects 24 h after administration. Collectively, these data indicate that DBS are suitable for routine doping control analysis of clenbuterol with a detection window of at least 3 days after oral administration of 80 μg.     

氨溴特罗治疗儿童急性支气管炎临床观察

目的：探讨氨溴特罗口服液治疗儿童急性支气管炎的效果。方法：300例急性支气管炎患儿随机分成两组各150例。两组均在控制感染的基础上,治疗组口服氨溴特罗,对照组口服复方福尔可定,疗程5 d。观察两组临床疗效、不良反应和依从性。结果：治疗5 d后,治疗组总有效率（93.33%）明显高于对照组（84.67%）,差异有统计学意义（P〈0.05）;咳嗽、痰量、痰黏稠度、喘息评分、不良反应发生率和依从性等方面比较,差异均有统计学意义（P〈0.01或0.05）。结论：氨溴特罗治疗急性支气管炎疗效显著,安全可靠,依从性好。     

GC/MS分析牛尿中瘦肉精残留

目的:建立牛尿中"瘦肉精"的GC/MS分析方法,为保障食品安全提供有效的分析手段。方法:调节样品的pH为5.2,用乙酸乙酯-异丙醇提取,蒸干后用乙酸铵溶解,经固相萃取小柱净化,氮气吹干后经双三甲基硅基三氟乙酰胺(BSTFA)衍生,GC/MS分析。结果:以牛尿为基质,"瘦肉精"在20.0～160.0μg·L-1添加浓度范围内线性关系良好,r=0.9980,其回收率在65.6%～99.0%之间,检出限为0.3μg·L-1。结论:本方法专属性好,准确,杂质少,适用于牛尿中"瘦肉精"的检测。