Establishment of the Rex Rabbit Fluorosis Model and Detection of the Fluoride Content in Organs

In order to study the influence of different doses of sodium fluoride on rex rabbit,rex rabbit fluorosis model was established and the fluorine contents of blood,bone,liver,kidney and other organs in rex rabbit were examined to provide a theoretical reference for the further research. Rex rabbits (age (30±5) days,weight (1.1±0.2) kg) were divided into three groups:Control group,test group Ⅰ (10 mg/(kg·d) NaF group) and test group Ⅱ (20 mg/(kg·d) NaF group). The tests lasted 100 d. The results showed that,on the 100th day,fluoride contents of bone and tooth were significantly different (P<0.05),and they were positively correlated with the time and intake of fluoride;The fluoride contents of kidney and liver were slightly different (P>0.05),and they were not significantly different between both test groups (P>0.05).The fluoride contents of blood were not significantly different between group Ⅰ and group Ⅱ (P>0.05),but both had no significant changes compared with control group (P<0.05). Sodium fluoride as a fluoride source could be used to simulate the natural state of rex rabbit fluorine poisoning. The fluoride accumulating ability in bone and tooth were stronger while the ability in blood,liver and kidney were weaker.     

节约环保型食品毒理学综合性·设计型实验教学体系构建

为进一步适应社会和学科发展需要,提高食品毒理学的实验教学效果,分析了食品毒理学实验教学设计现状,从实验教学内容、方法、技能训练等体系进行了节约环保型食品毒理学综合性、设计型实验教学改革,充分开发实验动物使用价值,采用视频教学法和模拟仿真实验室教学,增加探索性实验设计,进一步增强学生的技能训练,为我国的食品质量与安全专业培养优秀人才。     

兽药土霉素对水稻幼苗根系及部分生理特性的影响

为了解抗生素对农作物生长的作用机理,选择中国养殖业中普遍使用的土霉素,采用水培试验研究了不同污染水平土霉素对苗期水稻根系生长、根系活力、叶片叶绿素含量和氧化酶活性等的影响。结果表明,土霉素污染对水稻地下部分的影响明显大于地上部分。低浓度（0.5和1 mg·L-1）的土霉素处理能促进水稻根系总长度和根表面积的增加,增强根系活力;但高浓度的土霉素（>5 mg·L-1）可显著降低水稻根系生物量,对根系活力、叶片叶绿素含量和氧化酶活性有明显的限制作用,增加根系相对质膜透性。研究认为,高浓度土霉素可对水稻幼苗产生毒害作用,限制水稻幼苗正常生长。     

A screening of multiple classes of pharmaceutical compounds for effect on preadult salmon lice Lepeophtheirus salmonis

The salmon louse, Lepeophtheirus salmonis Krøyer, is the major obstacle facing a sustainable future for farmers of salmonids in the North Atlantic Ocean. Medicinal compounds have been the most utilized tool to prevent salmon lice infestation; however, the active compounds have become less effective or considered environmentally unfriendly in the past years. Novel medicinal compounds are thus highly desired. In two experiment series, 26 medicinal compounds were screened for their efficacy against salmon lice, in a 30‐min exposure and 24‐h exposure, respectively. Pyriprole, imidacloprid, cartap and spinetoram were effective at 50 mg L^?1 in the short‐time exposure. In the 24‐h exposure, pyriprole, propoxur, cartap, imidacloprid, fenoxycarb, pyriproxyfen, nitenpyram, spinetoram, spiromesifen and diflubenzuron induced a high level of immobilization at 5 mg L^?1. The EC₅₀ values of the effective compounds were calculated in further titration studies for both exposure periods. Several physiological and biochemical pathways were discovered as possible targets for medicinal intervention against the salmon louse.     

浅谈雾霾天气的环境毒理效应

2013年1月5日至26日,全国多地出现雾霾天气,长三角、珠三角和京津冀等地区尤其严重。导致雾霾天气形成的一个重要因素就是空气中颗粒物含量的不断增加。颗粒物粒径越小,其吸附有害污染物的能力越强,危害程度越大。因此,探寻控制颗粒物产生、减少雾霾天气的途径十分重要。该文从雾霾的组成入手,分析雾霾天气形成的主要原因及其毒理学效应,并提出应对措施。     

转基因生物食用安全评价技术体系及其发展趋势

针对如何更加科学合理地评价转基因生物食用安全的问题,采用比较研究的方法对国际组织及我国对转基因生物的食用安全评价框架进行对比,结果表明:1)目前全球对转基因生物的食用安全评价主要包括新表达物质毒理学评价、致敏性评价、营养成分分析、全食品安全性评价、食品加工对食用安全的影响、抗生素抗性评价;2)虽然目前全球基本形成了对转基因生物食用安全评价的原则和技术体系框架,但由于新型生物技术产品的出现,转基因生物食用安全评价的具体过程存在争议;3)转基因生物食用安全评价体系需要在营养学检测方面构建作物营养数据库,在毒理学检测方面构建毒蛋白数据库,在致敏性检测方面建立体外细胞评价模型,在非期望效应方面构建非期望效应评价模型。综上,面对新型生物技术产品,需要继续发展、完善已经建立的转基因生物食用安全评价原则和技术体系,以更好地保障人类健康。     

重组溶葡萄球菌酶对大鼠的毒性试验

观察重组溶葡萄球菌酶经口给药对大鼠的急性毒性和长期毒性。急性毒性试验中,大鼠以每千克体重5 000 mg的剂量口服重组溶葡萄球菌,观察中毒症状并测定LD50。长期毒性试验中,大鼠以每天每千克体重口服72,360,1 800 mg重组溶葡萄球菌酶,连续给药180 d,观察给药后45 d、90 d、135 d和180 d时大鼠的生长发育、血液学、血液生化学、组织病理变化。结果表明,重组溶葡萄球菌酶口服对大鼠的LD50大于5 000 mg/kg,长期毒性试验未见明显毒性反应。说明重组溶葡萄球菌酶在规定剂量下使用是安全可靠的。     

獭兔氟中毒模型的建立及各器官氟含量测定

为研究不同剂量氟化钠对獭兔的影响,试验建立獭兔氟中毒模型并对獭兔血液、骨骼、肝脏、肾脏等器官氟含量进行测定。试验獭兔日龄（30±5） d,体重（1.1±0.2） kg,数量24只,分为3组：对照组、试验Ⅰ组（10 mg/（kg·d）氟化钠组）和试验Ⅱ组（20 mg/（kg·d）氟化钠组）,试验共100 d。结果表明,试验第100天测定的骨骼和牙齿氟含量在各组之间均差异显著（P<0.05）,且骨骼和牙齿的含氟量随时间和摄入氟剂量的增加而递增;肾脏和肝脏氟含量在各组之间均差异不显著（P>0.05）;试验Ⅰ、Ⅱ组间血液氟含量差异不显著（P>0.05）,但都与对照组差异显著（P<0.05）。氟化钠作为氟化物来源可用来建立獭兔自然状态氟中毒症,骨骼和牙齿累积氟能力强,血液、肝脏和肾脏累积氟能力弱。本试验为进一步研究獭兔氟中毒及其防制提供了理论参考。