Aflatoxicosis chemoprevention by probiotic Lactobacillius and lack of effect on the major histocompatibility complex

Turkeys are extremely sensitive to aflatoxin B₁ (AFB₁) which causes decreased growth, immunosuppression and liver necrosis. The purpose of this study was to determine whether probiotic Lactobacillus, shown to be protective in animal and clinical studies, would likewise confer protection in turkeys, which were treated for 11 days with either AFB₁ (AFB; 1 ppm in diet), probiotic (PB; 1 × 10¹¹ CFU/ml; oral, daily), probiotic + AFB₁ (PBAFB), or PBS control (CNTL). The AFB₁ induced drop in body and liver weights were restored to normal in CNTL and PBAFB groups. Hepatotoxicity markers were not significantly reduced by probiotic treatment. Major histocompatibility complex (MHC) genes BG1 and BG4, which are differentially expressed in liver and spleens, were not significantly affected by treatments. These data indicate modest protection, but the relatively high dietary AFB₁ treatment, and the extreme sensitivity of this species may reveal limits of probiotic-based protection strategies.     

阿维菌素类药物兽医临床驱虫应用研究进展

综述了阿维菌素类药物的药理作用、应用、耐药性、使用注意事项、毒理学及其残留等方面的研究进展。     

冰草提取物对桃蚜的杀虫活性及对体内两种酶活性的影响

重点介绍了冰草的不同溶剂提取物对桃蚜的杀虫活性及其对蚜虫体内蛋白酶、谷胱甘肽-S-转移酶活性的影响。结果表明,冰草氯仿和水提取物对桃蚜有较好的内吸活性,并对桃蚜体内蛋白酶、谷胱甘肽-S-转移酶活性均有明显抑制作用,而在触杀处理中,提取物对蚜虫各酶系活性的影响不明显。     

Advances in Toxicology of Nε-（carboxymethyl）- lysine （CML）

Advanced glycation end-products （AGEs） are products of non-enzymatic glycation of proteins, lipids or nucleic acids and other macromolecules. To be spe- cific, Nε-（carboxymethyl）-Iysine （CML） is one of the most important components of AGEs, which is wildly distributed in the body and can be formed in vivo or in food processing and heating processes. Previous studies have shown that CML is a ma- jor immunological epitope in AGEs and plays an important role in diabetes and its complications, as well as in the development and progression of aging. This review summarized recent advances in major source, toxicological hazard and control mea- sures of CML.     

食品毒理学实验教学改革探讨

着眼于食品毒理学实践性强、实验教学要求高的特点,针对食品毒理学实验教学存在的问题,从优化与丰富实验教学内容和类型、融合多种教学方式、激发学生实验学习兴趣、吸收学生参与预实验、突出学生实际操作能力考核和实现实验教学的有效延伸等方面,进行了有益的探索。实践证明,教学改革提高了学生实验学习主动性,增强了学生实验动手能力,改善了食品毒理学实验教学的效果。     

纳米材料生态毒理学研究进展

纳米技术给人类带来利益的同时也给人类及整个生态系统带来了潜在的危害。纳米材料毒理学的研究对于科学地评价纳米材料的潜在危害和对纳米材料的生产和应用进行科学的管理是十分必要的。概述了纳米材料生物毒理学的研究进展,提出了研究中存在的不足,并对其研究前景进行了展望。     

超常量菜籽饼喂肉用仔鸡的毒理学研究

不脱毒云南产机榨菜籽饼以15%、19%、24%、30%等超常量饲喂肉用仔鸡,测定其生长性能,随机抽样进行甲状腺、血清T3、T4含量,肝功能、肌肉品质等指标,结果表明,肉鸡增重、胴体重、屠宰率显著降低;甲状腺重量增加,滤泡肿大,T3、T4水平下降。     

Metabolism of O,O,S-trimethyl phosphorothioate in rats after oral administration of a toxic dose,and the effect of coadministration of its antagonistic thionate isomer

The in vivo metabolism of [¹⁴CH₃S]- and [¹⁴CH₃O]O,O,S-trimethyl phosphorothioate (OOS) was followed in rats after oral administration of threshold or LD₅₀ toxic doses of 20 or 60 mg/kg. Similar metabolic studies were conducted with coadministration of 1% O,O,O-trimethyl phosphorothionate (OOO), which prevented all signs of delayed toxicity, including weight loss. When administered alone, OOS was metabolized mainly (50–60%) via removal of the CH₃S moiety, which was largely converted to expired CO₂. Approximately 20% of the compound was O-demethylated, presumably by conjugation with glutathione, and then further metabolized to CO₂. Major urinary products were identified as O,O-dimethyl phosphoric acid (50–60%) and O,S-dimethyl phosphorothioic acid (～20%). Coadministration of OOO caused a slight decrease (～5%) in the cleavage of the CH₃S moiety, indicated by a reduction in ¹⁴CO₂ from [¹⁴CH₃S]OOS and a quantitatively similar increase in the formation of O,S-dimethyl phosphoric acid. Limited pharmacokinetic studies indicated that OOS was rapidly absorbed and distributed throughout the body. Coadministration of 1% OOO caused a slight increase in the blood half-life of parent OOS when administered at 60 mg/kg. It was concluded that a small proportion of the cleavage of the CH₃S moiety from OOS is involved in the intoxication process, and that this intoxication reaction is specifically inhibited by OOO.     

兽用二氨基嘧啶类抗菌增效剂毒理学研究进展

抗菌增效剂是一类广谱、高效、低毒的药物,广泛应用于临床.本文对二氨基嘧啶类抗菌增效剂进行详细的毒性作用综述,主要包括急性毒性、长期毒性、遗传毒性等,为评价其安全性,指导临床合理使用,开发新药,避免其应用危害提供参考。