硫酸二乙酯对家蚕毒性的半致死剂量测定

硫酸二乙酯(DES)是一种能诱导生物体产生随机点突变的烷化剂。为了完善利用DES诱导家蚕突变的实验技术,采用不同剂量DES分别处理家蚕蛹、蛾、卵,检测DES对不同发育时期家蚕毒性的半致死剂量(LD50),结果表明DES对不同发育时期家蚕的LD50值存在显著差异:化蛹第5天的雌雄蛹分别为2 333.90μg/头和2 369.50μg/头;刚羽化雄蛾为156.39μg/头;蚕卵为13.23 mg/mL。研究结果可作为DES对家蚕的最适诱变剂量和家蚕诱变最佳发育时期选择的参考依据。     

饲料中己烯雌酚的检测方法

己烯雌酚（diethylstilbestrol，简称DES）诞生于20世纪40年代，为第一个口服有活性的人工合成雌激素，化学名为1，2-双（4-羟苯基）-1，2-二乙基乙烯，俗名乙底酚，为无色结晶或白色结晶性粉末，在人造雌激素中是作用较强的一种。医学上主要用于治疗雌激素缺乏症。但是南于其具有促进动物生长、增加蛋白质沉积和提高饲料转化率的作用，曾经作为促生长剂广泛应用于畜牧养殖业。自从人们发现动物因食用含DES的饲料在组织中残留给人类健康带来危害以来，世界上绝大多数国家禁止在食品动物中使用DES。2002年我国农业部规定DES及其盐、酯制剂取消在所有食品动物的所有用途。     

生鲜肉品中己烯雌酚残留的检测方法此较研究

己烯雌酚（Diethylstilbestrol，DES）是人工合成的非甾体雌激素，在兽医临床上，主要用于治疗胎衣不下、子宫内膜炎和排除死胎等。在畜牧生产上。己烯雌酚对雌性动物的生殖、泌乳和产蛋的效应有正负双向调节作用。然而，己烯雌酚的毒副作用也日益凸现。为了寻求一种经济、简便、灵敏、特异性强的测定方法。试验以残留量较高的肝脏为检测对象，分别用高效液相色谱法、荧光分光光度计法、毛细管区带电电泳法对其中的DES含量进行检测，同时以己烯雌酚片剂为参照对3种检测方法的最低检测限进行了比较．     

己烯雌酚人工抗原的合成及其抗体制备

以己烯雌酚 (DES)、琥珀酸酐和牛血清白蛋白 (BSA)等为主要原料 ,采用混合酸酐反应 ,首先合成己烯雌酚半琥珀酸酯 (DES- HS) ,经质谱分析鉴定后 ,再将 DES- HS结合到 BSA上 ,并用 SDS- PAGE对 DES- HS- BSA进行测定。以DES- HS- BSA免疫家兔 6次 ,用琼脂双扩散试验测定抗体。试验结果表明 ,高分辨质谱测得合成的 DES- HS分子量为36 8;BSA- HS- DES的 SDS- PAGE图谱经相关软件分析表明 ,单个 BSA上结合有 32个 DES- HS;琼脂扩散试验结果证实 ,免疫兔血清中含有抗 DES的抗体。本试验为下一步研制 DES残留免疫检测试剂盒及抗 DES单抗奠定了基础     

二乙基己烯雌酚对成年仓鼠睾丸一氧化氮生成和生精细胞凋亡的影响

探讨了在二乙基己烯雌酚（DES）诱发成年动物生精细胞凋亡过程中睾丸一氧化氮（NO）生成和生精细胞一氧化氮合酶（eNOS和iNOs）表达的变化，以期为阐明DES诱发生精细胞凋亡机理的研究提供基础资料。成年雄性仓鼠皮下注射不同剂量DES（分别为0．01、0．1和1mg／kg体重），连续注射7d后取其睾丸，进行NO含量的测定和eNOS、iNOS免疫组化染色。电镜观察生精细胞超微结构的变化，并用TUNEL法检测睾丸中生精细胞凋亡的变化，苏丹Ⅲ染色法检测睾丸生精小管内脂滴分布的变化。结果显示：NO的生成与DES呈剂量依赖性。DES处理后，在1mg／kg体重剂量组，大量生精细胞表达eNOS和iNOS，并出现大量凋亡，退化的生精细胞胞浆内有大量髓样结构，并有大量脂滴分布于生精细胞内和细胞间。eNOS和iNOS阳性生精细胞与凋亡的生精细胞数量和类型基本一致，主要为精母细胞和圆形精子细胞。     

己烯雌酚对成年仓鼠附睾组织形态的影响

探讨环境内分泌干扰物已烯雌酚(DES)对成年动物附睾组织形态的影响,将DES皮下注射成年仓鼠(剂量为每天1mg/kg)连续1周后,用光镜和电镜观察附睾组织形态的变化,并用脱氧核糖核酸末端转移酶介导的dUTP缺口末端标记法(TUNEL)检测附睾管上皮细胞和精子的凋亡情况。结果,DES处理后附睾头和附睾尾萎缩,附睾管变细。附睾管上皮细胞形态出现明显的改变,附睾上皮细胞和精子均出现大量凋亡,附睾管管腔内充满发育异常的生精细胞,少见长形精子。结果表明,DES能诱发成年动物附睾形态的改变,这可能是造成成年动物生精障碍的重要原因。     

苜蓿抗性愈伤组织诱导的初步研究

以硫酸二乙酯（DES)和紫外线(UV)对准格尔苜蓿愈伤组织进行诱变处理，筛选其半致死浓度和剂量。对诱变处理后的材料进行脯氨酸含量测定。结果表明，脯氨酸含量明显高于对照。筛选出具有抗性的苜蓿愈伤组织，为苜蓿抗性育种提供基础材料。     

饲料中己烯雌酚ELISA检测方法的建立

为了建立一种饲料中己烯雌酚(DES)残留的检测方法,试验采用酶联免疫吸附试验(ELISA)进行检测,并对该方法的检测限、准确度、精密度和特异性等参数进行考察。结果表明:本试剂盒的线性工作范围为0.1~8.1μg/kg,IC50浓度为0.417μg/kg,对饲料中DES的检测限为5μg/kg;对饲料样品中DES的添加回收率范围为83%~107%,批内变异系数≤5.7%,批间变异系数≤6.3%;与DES类似物无交叉反应。本研究所建立的ELISA检测方法具有简单、灵敏、准确等特点,适用于饲料中DES残留的快速检测。     

己烯雌酚对胎鼠睾丸发育的影响研究

为了研究己烯雌酚(DES)对胎鼠睾丸发育的影响,将雌鼠随机分为对照组和试验1、2、3组,每组10只。3个试验组母鼠从怀孕第10~18天分别每天连续皮下注射DES 2、4和8μg只/,对照组则注射同等剂量的生理盐水,于最后一次注射后2 h取出胎鼠睾丸。常规石蜡切片,HE染色镜检,并应用免疫组织化学方法检测雄性胎鼠睾丸中增殖细胞核抗原(PCNA)的表达情况。结果显示:2μg组睾丸发育情况接近对照组,无明显病理变化;4μg组仅见生殖母细胞和间质细胞数量减少;8μg组可见生殖母细胞核仁不明显,支持细胞数量减少,间质细胞溶解;随着用药剂量的增加,睾丸中PCNA含量显著降低(P<0.05)。结果表明DES会抑制胚胎期睾丸细胞的增殖,从而影响睾丸的发育,破坏睾丸的组织结构。     

黄芪多糖对己烯雌酚诱导的小鼠睾丸损伤保护作用研究

为探讨黄芪多糖(APS)对己烯雌酚(DES)诱导的成年小鼠睾丸损伤的保护作用,将40只雄性小鼠分为正常对照(A)、3个黄芪多糖组(B、C、D)和己烯雌酚组(E)。B组、C组、D组分别灌服20、60、100mg/kg的APS,A组每只灌胃0.2mL含量为5g/L的羟甲基纤维素钠,E组每只灌胃0.2mL生理盐水。4h后除A组外,其他4组腹腔注射40mg/kg的DES,A组腹腔注射相同剂量橄榄油。连续给药7d。处理结束后计算睾丸重量及其脏器系数,检测睾丸病理学变化,检测睾丸中超氧化物歧化酶(SOD)活力、谷胱甘肽过氧化物酶(GSH-Px)活力和丙二醛(MDA)的含量;检测血清中睾酮(T)、促黄体素(LH)和促性腺激素释放激素(GnRH)的水平。结果表明,与DES模型组相比较,APS各组睾丸脏器系数变化差异显著,睾丸组织学变化有明显改善。抗氧化结果显示,APS各剂量组睾丸组织中SOD、GSH-Px活力均高于DES组,差异显著,其中100mg/kg组最高。APS各剂量组睾丸组织中MDA含量均低于DES组,差异显著,其中60mg/kg组最低。APS各剂量组血清中T、LH、GnRH的含量均显著增加。结果提示,APS对DES诱导的小鼠睾丸损伤有显著缓解作用。     

Diethylstilboestrol—historical background and current regulatory status

Diethylstilboestrol is a non-steroidal orally active oestrogen that in the past has been widely used in a variety of conditions in both medical and veterinary fields. In recognition of potential systemic availability to man of DES in the tissues of treated food-producing animals, together with an understanding of the potential teratogenic and carcinogenic toxicity of DES in man, the veterinary use of DES has been restricted to oral use in small animals only. Use of DES is prohibited in all food-producing animals.     

Diethylstilboestrol—clinical pharmacology and alternatives in small animal practice

Diethylstilboestrol is currently only available in Australia for oral use in dogs and cats. As an orally and systemically active non-steroidal oestrogen, DES has been widely used in small animal veterinary medicine for a variety of indications. A review of the literature reveals that many of the recommendations for use are founded on anecdotal or unreported clinical observations. While many of the uses may be valid, accurate determinations of optimum dosing regimens have not been defined. This is especially unfortunate in view of the potential toxicity of DES to small animals. Nevertheless, particularly in cases of low-dose intermittent administration, oral DES appears indicated at least until data on alternative safe and effective interventions become available.     

己烯雌酚免疫分析技术研究进展

己烯雌酚为人工合成的二苯乙烯类雌激素药物,曾经作为促生长剂广泛应用于畜牧业。但国内研究表明,己烯雌酚存在着潜在的致癌性。因此,近年来,其在饲料及动物性食品中的残留检测倍受关注,但己烯雌酚属于小分子化合物,不具备免疫原性。己烯雌激酚人工抗原主要采用混合酸酐反应(氯甲酸异丁酯法)将半抗原己烯雌酚与载体蛋白牛血清蛋白连接制备人工免疫原,并采用碳二亚胺法将半抗原己烯雌酚与载体蛋白卵清蛋白连接制备人工包被原。文章对己烯雌酚的免疫分析技术进行了综述。     

Anesthetic Potency of Desflurane in the Horse: Determination of the Minimum Alveolar Concentration

Objective — To determine the minimum alveolar concentration (MAC) of desflurane (DES) in the horse.
Study Design — Prospective study.
Animals — Six healthy adult horses (three males and three females) weighing 370 ±16 kg and aged 9 ±2 years old.
Methods — Anesthesia was induced with DES vaporized in oxygen via a face mask connected to a large-animal, semiclosed anesthetic circle system. The horses were endotracheally intubated and positioned in right lateral recumbency. Inspired and end-tidal DES were monitored using a calibrated Ohmeda RGM 5250 multigas analyzer (Ohmeda-BOC, Spain). The MAC of desflurane that prevented gross purposeful movement in response to 60 seconds of noxious electrical stimulation of oral mucous membranes was determined.
Results — The time from the start of DES administration to lateral recumbency was 6.1 ±0.9 min. The MAC of DES in these horses was 7.6 ±0.4%. Time required for the animal to regain sternal recumbency after 98 ±4 minutes of anesthesia was 6.6 ±0.5 minutes and the time to standing was 14.3 ±2.7 minutes.
Conclusions — The MAC of desflurane in these horses was 7.6 ±0.4%. DES provided a rapid induction to, and recovery from, anesthesia.
Clinical Relevance — Desflurane offers the potential for more precise control during anesthesia, and may allow a faster and uneventful recovery. It is important to know the MAC of an inhalant to use it clinically.     

Cardiopulmonary effects of desflurane in horses

OBJECTIVE: To determine the cardiopulmonary effects of desflurane (DES) in horses. ANIMALS: Six healthy adult horses, three males and three females, aged 9 +/- 4 (mean +/- SD) years and weighing 370 +/- 36 kg. MATERIALS AND METHODS: Anaesthesia was induced with an O2 (10 L minute(-1)) and DES mixture (vaporizer setting 18%). After oro-tracheal intubation, horses were positioned in right lateral recumbency. Anaesthesia was maintained with DES in O2 (20 mL kg(-1) minute(-1)) delivered through a large animal circle breathing system. The minimum alveolar concentration of DES (MAC(DES)) that prevented purposeful movement in response to 60 seconds of electrical stimulation of the oral mucous membranes was determined for each horse. The delivered concentration of DES was then increased to achieve end-tidal concentrations corresponding to 1.5 x MAC(DES), 1.75 x MAC(DES), and 2.0 x MAC(DES). Heart rate (HR), mean arterial blood pressure (MAP), respiratory rate (fr), tidal volume (VT), minute volume (VM) and core temperature were determined, and blood samples for arterial blood gas analysis taken at each DES concentration. All data were analysed by two-way anova for repeated measures and Fisher's test for multiple comparisons. A probability level of p < 0.05 was applied. RESULTS: Desflurane concentrations of 2.0 x MAC(DES) increased HR whereas lower concentrations did not. Mean arterial pressure was not affected by 1.0 x MAC(DES) 1.5 x MAC(DES) or 1.75 x MAC(DES), whereas it decreased at 2.0 x MAC(DES). All concentrations of DES examined significantly depressed fr, VT and VM. CONCLUSIONS AND CLINICAL RELEVANCE: Desflurane concentrations between 1.0 and 1.75 x MAC(DES) reduces fr and VM but does not affect HR or MAP in horses.     

Application of diethylstilbestrol dipropionate in bulls. II. Residues in bile, liver, kidney, muscle tissues and application site

The second part of an experiment is described in which 20 one year old bulls were injected with diethylstilbestrol (DES) dipropionate containing preparations. Analysis of DES content was performed in several tissues, such as the injection site, diaphragm muscle, psoas muscle, liver, kidney and bile. In the injection site appreciable amounts of DES were found. Measurable amounts of DES were also found in liver and kidney until 4 weeks after injection. In bile, DES concentrations were even higher than those in urine, and were well correlated with DES concentrations in urine. Implications for screening purposes are discussed.     

Estrogenic Properties of Locoweed (Astragalus lentiginosus)

Locoweed, Astragalus lentiginosus was extracted with ether (EE) and water (WE). These and the plant residue were mixed with basal diet (BD) and fed to weanling female mice to determine the plant's estrogenic activity. Diethylstilbesterol (DES) was fed as a control. Uterine weight was taken at five to seven days. Three feeding trials were conducted.

In Trial 1 one group of mice was fed a basal diet and one group the basal diet plus EE 1 gm/mouse. The uteri from mice receiving EE were heavier (P <.01) than from those receiving BD.

In Trial 2 mice were fed 0.10 gmEE/mouse, 0.15 gm EE/mouse, 0.10 and 0.15 µg DES/mouse and basal diet. The uteri from the DES fed mice were heavier (P <.01) than the others. The uteri from the EE mice and the BD mice were lighter than those of the DES mice, but there was no difference between the uteri from the EE and BD. This was thought to be due to the level of EE fed.

In Trial 3 three levels of EE, 1.30, 0.86, and 0.42 gm/mouse, two levels of DES, 0.075 and 0.150 µg/mouse, one level water extract, 3 gm/mouse, plant residue, 3 gm/mouse, and basal diet were fed. The uteri from EE mice were heavier (P <.01) than the DES and DES heavier (P <.01) than WE or BD fed mice. Lesions typical of locoweed poisoning were found in WE fed mice. It was concluded that locoweeds contain high levels of estrogenic compounds as well as those causing pathological lesions.

     

Recovery of fertility in quinestrol‐treated or diethylstilbestrol‐treated mice: Implications for rodent management

Fertility control is an alternative strategy to traditional culling for the management of rodent pests. Previous studies have demonstrated that quinestrol is a potential contraceptive for male rodents, but the recovery of fertility in quinestrol‐treated rodents has not been evaluated. This study used C57BL/6J mice to evaluate the recovery rate of male fertility after the administration of quinestrol. Diethylstilbestrol (DES), a non‐steroid estrogenic compound, was used for comparison. Different groups of mice were treated with 1 mg/kg quinestrol, 1 mg/kg DES, or castor oil separately for 7 days. These mice were then killed on days 8, 22 and 50 respectively. Our results indicated that the weight of epididymides and seminal vesicles decreased significantly on days 8 and 22 in quinestrol/DES‐treated mice, with extensive histological changes in the seminiferous tubules. Sperm concentrations in the cauda epididymal fluid were significantly reduced on days 8 and 22 in both quinestrol and DES treatment groups and on day 50 for the DES, but not the quinestrol group. Further analysis revealed that DES‐treated mice exhibited a higher proportion of abnormal sperm accumulation in the epididymis, indicating that the normal sperm transportation to the cauda epididymis was blocked. Our results indicate that the anti‐fertility effects on male mice given quinestrol were of shorter duration than for those receiving DES at the dose of 1 mg/kg body weight.     

Suppressed development of cultured mouse and swine embryos by diethylstilbestrol

Effects of prolonged exposure to the synthetic estrogen diethylstilbestrol (DES) on in vitro development of early mouse and swine embryos were investigated. Two-cell mouse embryos cultured in Whitten's medium (WM) for 192 h were exposed to 10(-4), 10(-7) or 10(-10) M DES dissolved in 1, 10(-3) or 10(-6)% ethanol, respectively. One-cell to eight-cell swine embryos were cultured in WM for 192 h containing 10(-4) or 10(-7) M DES dissolved in 1 and 10(-3)% ethanol, respectively. Embryos cultured in WM containing 1 (0 DES1), 10(-3) (0 DES2) or 10(-6)% ethanol (0 DES3) served as controls. Hatching was inhibited (P less than .05) in mouse embryos cultured in 10(-4) M DES (3.0 +/- 2.1% vs 0 DES1, 25.1 +/- 3.7%). Similar (P greater than .10) percentages of mouse embryos hatched in 10(-7) M DES (36.4 +/- 5.4% vs 0 DES2, 29.1 +/- 5.7%) and 10(-10) M DES (44.4 +/- 4.4% vs 0 DES3, 38.9 +/- 5.3%). Diethylstilbestrol at a concentration of 10(-4) M failed to affect the development of one- to eight-cell swine embryos into blastocysts. However, compared with 0 DES2, 10(-7) M DES reduced (P less than .05) the number of swine blastocysts developing from one- to two-cell (36 vs 78%) and three- to four-cell embryos (50 vs 84%). No significant effects of 10(-7) M DES were detected on the ability of six- to eight-cell swine embryos to develop into blastocysts.(ABSTRACT TRUNCATED AT 250 WORDS)