硝唑尼特抗免疫抑制小鼠隐孢子虫活性试验

研究硝唑尼特抗隐孢子虫的活性,采用地塞米松抑制昆明鼠免疫功能,经口接种感染微小隐孢子虫孢子化卵囊,成功制备出微小隐孢子虫感染的动物模型。将感染微小隐孢子虫的小鼠随机分为感染对照组以及高、中、低剂量3个药物剂量组,连续经口灌服硝唑尼特治疗1周,观察每只小鼠每天排出微小隐孢子虫卵囊的数量,以感染抑制率来评价硝唑尼特抗微小隐孢子虫的活性。结果表明,200 mg/(kg.d)剂量组能显著减少小鼠排出隐孢子虫卵囊的数量,对治疗微小隐孢子虫感染具有较好的疗效。     

硝唑尼特混悬液对鸡柔嫩艾美尔球虫病治疗效果研究

采用人工接种柔嫩艾美尔球虫孢子化卵囊的方法复制鸡球虫病模型,检测发病率、死亡率、存活率、增重量等指标,研究硝唑尼特混悬液对鸡球虫病的临床治疗效果.结果显示,高、中、低剂量的硝唑尼特抗球虫指数分别为163.6、168.3、137.9;硝唑尼特混悬液与癸氧喹酯对照组相比差异显著(P＜0.05),与妥曲珠利对照组相比差异不显著(P＞0.05);硝唑尼特混悬液高剂量组和中剂量组差异不显著(P＞0.05),抗球虫指数为中效,低剂量组的抗球虫指数为低效.试验证明,硝唑尼特混悬液对鸡柔嫩艾美耳球虫病具有一定的治疗效果,有望开发为新的抗球虫药物.     

硝唑尼特对斑马鱼和赤子爱胜蚓的急性毒性试验

通过对斑马鱼和赤子爱胜蚓的急性毒性试验,研究了硝唑尼特的生态毒性.结果表明,硝唑尼特在静水条件下对斑马鱼24 h LC50为2.312 mg/L、48 h和72 h LC50为2.033 mg/L、96 h LC50为1.968 mg/L,按鱼类急性毒性分级标准,硝唑尼特属高毒类物质;硝唑尼特滤纸法对赤子爱胜蚓24 h...     

硝唑尼特的多重作用机制及应用研究进展

硝唑尼特(NTZ)是上世纪七十年代开发的一个抗寄生虫药物,已被美国食品药品监督管理局(FDA)批准用于治疗隐孢子虫或蓝氏贾第鞭毛虫引起的腹泻,被中国农业农村部批准用于治疗犬绦虫病。近年来的研究发现,硝唑尼特不仅能抗多种寄生虫,而且对多种危害严重的人或动物病原菌、病毒也具有很好的活性,但是研究发现硝唑尼特对各种病原体的活性作用机制却各不相同。本文主要综述了硝唑尼特对多种病原体的作用及其可能的机制,从而为硝唑尼特的利用和相关研究提供资料。     

液质联用测定犬血浆中硝唑尼特主要活性代谢产物的试验

为了研究硝唑尼特在Beagle犬体内的药代动力学特征,试验用液质联用方法检测硝唑尼特的主要代谢产物——替唑尼特。结果发现:替唑尼特在0.05~25μg/mL范围内线性关系良好,r=0.999 9(n=7),该方法日内精密度1.5%(n=3),日间精密度3.0%(n=3)。说明该方法灵敏度高,操作简便,可以用于硝唑尼特在犬体内的药代动力学研究。     

新型抗原虫药硝唑尼特

<正>硝唑尼特(nitazoxanid,NTZ)是一种新的抗原虫药,由Romark实验室创制,首次报道于1976年,化学名称苯酚乙酸酯。2002年由美国FDA批准硝唑尼特液体制剂治疗隐孢子虫病和肠贾第鞭毛虫所致1~11岁儿童的腹泻。在国内,中国农业科学院上海兽医研究所对硝唑尼特及其混悬剂进行了研究,但至今仍未上市,也无该产品     

硝唑尼特对利什曼原虫的体外药效试验

为观察硝唑尼特在不同浓度、不同作用时间对离体杜氏利什曼原虫的药效作用,以6个不同浓度(6.25、12.5、25、50、100、200μg/mL)的硝唑尼特分别作用体外培养的杜氏利什曼原虫前鞭毛体48h和72h。结果显示,随着浓度和作用时间的增加,药物对虫体的抑制率升高,显微镜下可见虫体变形,核和动基体不完整,细胞质内有空泡,鞭毛脱落,即硝唑尼特对杜氏利什曼原虫有较好的抑杀作用。     

硝唑尼特对四翼无刺线虫的驱虫效果

20只自然感染四翼无刺线虫的雌性昆明系小鼠,随机分成4组,每组5只,常规饲喂。第1~3组小鼠分别以200、400、800 mg/kg剂量的硝唑尼特灌胃,第4组设为空白对照组,每24 h一次,连续灌胃5 d。用虫卵减少率和粗计驱虫率作为评价药物效果的指标。结果显示,硝唑尼特对四翼无刺线虫的驱虫效果随药物剂量的增加而提高,以800 mg/kg剂量效果最好。     

硝唑尼特干混悬剂主要活性代谢物在狗体内的药物动力学研究

硝唑尼特(nitazoxanide,简称NTZ),为硝基噻唑酰胺类化合物,是一种有效的、广谱的抗动物与人体寄生虫、细菌和真菌感染的药物.1984年报道用作抗人体无钩绦虫(Taenia saginata)和微小膜壳绦虫(Hymenolepis nana)感染,单剂量即可起效.     

气相色谱法检查硝唑尼特药物中的有机溶剂残留量

建立一个气相色谱条件同时分离测定硝唑尼特中四氢呋喃及乙醇的含量。以PEG-20000为固定相,柱长25m,进样口温度180℃,检测器温度200℃,柱温采用程序升温,氮气为载气,以二甲基甲酰胺为溶剂,以1,4-二氧六环为内标。四氢呋喃及乙醇进样量分别在0．0708～0．2126峭和0．158～1．106μg,峰面积比与浓度呈良好的线性关系,精密度良好。此气相色谱条件可同时测定硝唑尼特中四氢呋喃及乙醇的含量,方法简便准确。     

Nitazoxanide(NTZ)干混悬剂驱除犬复孔绦虫作用研究

为了考察Nitazoxanide干混悬剂驱除犬复孔绦虫的效果，选择自然感染复孔绦虫的犬，按200mg/kg bw的剂量口服此干混悬剂进行驱虫效果研究。结果表明该制剂对犬复孔绦虫有良好的驱杀作用，效果确实、可靠。     

硝唑尼特治疗犬贾第虫病的研究

选择试验犬8只,将其随机分为4个小组,每组2只.连续6 d对8只试验犬分剐进行粪检,确定无贾第虫感染后,用体外纯培养的犬贾第虫滋养体接种试验犬,然后每天采集试验犬新鲜粪便40 g,用硫酸锌漂浮法进行粪检,当检测犬贾第虫感染呈阳性时,分别用1、2、4 mg/kg体质量剂量的硝唑尼特时1、2、3组试验犬进行灌服治疗,第4组试验犬不用药作为对照.用药后,每天以同样的方法检测贾第虫包囊,并计数.结果表明,以2、4 mg/kg体质量给药的试验犬1 d后粪检结果转为阴性,以1 mg/kg体质量给药的试验犬4 d后粪检结果转为阴性.结果表明以2、4 mg/kg体质量剂量的硝唑尼特对犬贾第虫痛有很好的疗效.     

Experimental infection of cats with Tritrichomonas foetus.

OBJECTIVE: To determine whether infection with Tritrichomonas foetus causes diarrhea in specific-pathogen-free or Cryptosporidium coinfected cats. ANIMALS: 4 cats with subclinical cryptosporidiosis (group 1) and 4 specific-pathogen-free cats (group 2). PROCEDURE: Cats were infected orogastrically with an axenic culture of T. foetus isolated from a kitten with diarrhea. Direct microscopy and protozoal culture of feces, fecal character, serial colonic mucosal biopsy specimens, and response to treatment with nitazoxanide (NTZ; group 1) or prednisolone (groups 1 and 2) were assessed. RESULTS: Infection with T. foetus persisted in all cats for the entire 203-day study and resulted in diarrhea that resolved after 7 weeks. Group-1 cats had an earlier onset, more severe diarrhea, and increased number of trichomonads on direct fecal examination, compared with group-2 cats. Use of NTZ eliminated shedding of T. foetus and Cryptosporidium oocysts, but diarrhea consisting of trichomonad-containing feces recurred when treatment was discontinued. Prednisolone did not have an effect on infection with T. foetus but resulted in reappearance of Cryptosporidium oocysts in the feces of 2 of 4 cats. During necropsy, T. foetus was isolated from contents of the ileum, cecum, and colon. Tritrichomonas foetus organisms and antigen were detected on surface epithelia and within superficial detritus of the cecal and colonic mucosa. CONCLUSIONS AND CLINICAL RELEVANCE: After experimental inoculation in cats, T. foetus organisms colonize the ileum, cecum, and colon, reside in close contact with the epithelium, and are associated with transient diarrhea that is exacerbated by coexisting cryptosporidiosis but not treatment with prednisolone.     

Equine protozoal myeloencephalitis.

Recent advances in the understanding of the parasite life cycle, epidemiology, clinical signs, diagnosis, treatment, and prevention of EPM are reviewed. The NAHMS Equine '98 study and a controlled retrospective study from The Ohio State University College of Veterinary Medicine identified a number of risk factors associated with development of the disease. The national annual incidence of EPM was 1% or less depending on the primary use of the animals. Increased disease risk was associated with age (1-5 and > 13 years of age), season (lowest in winter months and increasing with ambient temperature), previous stressful events, the presence of opossums, the use of nonsurface water drinking systems, and failure to restrict wildlife access to feed. Horses that received treatment were 10 times more likely to improve, and those that improved were 50 times more likely to survive. A number of recent studies confirmed that horses can be experimentally infected with S. neurona; however, large numbers of sporocysts are apparently necessary to achieve infection, and clinical signs and abnormal CNS histology are only seen inconsistently. Results suggest that CNS infection and positive CSF immunoblot findings may be transient phenomena among naturally infected horses. Although immunosuppression may be involved in the development of EPM, some element of the immune response seems to be necessary for the development of clinical signs. Use of the standard immunoblot test for the detection of anti-S. neurona antibodies in CSF continues to provide the most useful adjunct to a detailed neurologic examination for the diagnosis of EPM. Test sensitivity and specificity were 89% in 295 horses euthanatized because of neurologic disease, of which 123 were confirmed cases of EPM. The PPV was 85%, and the NVP was 92%. A number of promising new EPM treatments are under investigation. In addition to standard SDZ/PYR therapy, toltrazuril, ponazuril, diclazuril, and NTZ have shown promise as possible alternatives.     

The pharmacokinetics of nitazoxanide active metabolite (tizoxanide) in goats and its protein binding ability in vitro

Zhao, Z., Xue, F., Zhang, L., Zhang, K., Fei, C., Zheng, W., Wang, X., Wang, M., Zhao, Z., Meng, X. The pharmacokinetics of nitazoxanide active metabolite (tizoxanide) in goats and its protein binding ability in vitro. J. vet. Pharmacol. Therap. 33 , 147–153. The pharmacokinetics of tizoxanide (T), the active metabolite of nitazoxanide (NTZ), and its protein binding ability in goat plasma and in the solutions of albumin and α‐1‐acid‐glycoprotein were investigated. The plasma and protein binding samples were analyzed using a high‐performance liquid chromatography (HPLC) assay with UV detection at 360 nm. The plasma concentration of T was detectable in goats up to 24 h. Plasma concentrations vs. time data of T after 200 mg/kg oral administration of NTZ in goats were adequately described by one‐compartment open model with first order absorption. As to free T, the values of t_1/2Ka, t_1/2Ke, T_max, C_max, AUC, V/F_(c), and Cl_(s) were 2.51 ± 0.41 h, 3.47 ± 0.32 h, 4.90 ± 0.13 h, 2.56 ± 0.25 μg/mL, 27.40 ± 1.54 (μg/mL) × h, 30.17 ± 2.17 L/kg, and 7.34 ± 1.21 L/(kg × h), respectively. After β‐glucuronidase hydrolysis to obtain total T, t_1/2ke, C_max, T_max, AUC increased, while the V/F_(c) and Cl_(s) decreased. Study of the protein binding ability showed that T with 4 μg/mL concentration in goat plasma and in the albumin solution achieved a protein binding percentage of more than 95%, while in the solution of α‐1‐acid‐glycoprotein, the percentage was only about 49%. This result suggested that T might have much more potent binding ability with albumin than with α‐1‐acid‐glycoprotein, resulting from its acidic property.     

福州动物园圈养鸟类肠道寄生虫调查

为调查福州动物园圈养鸟类消化道寄生虫感染情况,采集16种禽类31份粪便样品,应用饱和盐水漂浮法和自然水洗沉淀法收集虫卵,麦克斯特计数法对采集的粪便样本进行虫卵测定。检查结果显示,寄生虫感染阳性样品数有23份,占样品总数的74%。总共检出6种寄生虫感染,按感染例数从大到小排序为:球虫(9例)、吸虫(7例)、绦虫(6例)、线虫(5例)、鞭虫(4例)、纤毛虫(3例)。感染寄生虫的禽类中,孔雀的感染强度最高,EPG为9 150个/g;其次是巨嘴鸟,EPG为4 500个/g;第三是东方白鹳,EPG为3 300个/g。其他鸟类的EPG分布在0~2 100个/g。该调查结果为福州动物园圈养鸟类寄生虫病的防治以及制定科学的驱虫程序提供可靠的依据。     

猪繁殖与呼吸综合征、猪圆环病毒2型、猪伪 狂犬病病毒混合感染的检测分析

本研究采用RT-PCR方法对2010年12月至2011年11月采集于豫西地区的170份疑似PRRSV感染猪病料进行病原检测,得到102份高致病性PRRSV阳性样本,在此基础上应用PCR方法检测PCV2和PRV的感染情况,并计算混合感染率。试验结果显示,豫西地区PRRS发病猪主要疫病的总混合感染率为58.52%,二重混合感染率为39.21%,三重混合感染率为19.61%,其中PRRSV/PCV2型二重混合感染最严重,混合感染率达33.33%;春夏和秋冬总混合感染率分别为48.57%、81.25%,而且不管是二重还是三重混合感染,秋冬均比春夏更严重,尤其是PRRSV/PCV2/PRV型三重混合感染,秋冬与春夏季节的混合感染率相差较大,分别为37.50%、11.43%;PRRS发病猪从哺乳期到育肥期都有混合感染,混合感染率分别为42.10%、50.00%、100.00%,混合感染程度逐渐加重,主要集中在育肥期;不同发病时期的最高混合感染型也有所不同,其中哺乳期最高混合感染型为PRRSV/PCV2,混合感染率为42.10%,保育期最高混合感染型为PRRSV/PCV2、PRRSV/PCV2/PRV,混合感染率均为22.73%,育肥期最高混合感染型为PRRSV/PCV2/PRV,混合感染率为50.00%。本研究反映了豫西地区PRRS发病猪群与猪圆环2型及猪伪狂犬病的混合感染情况和规律,为该地区PRRS及其混合感染的临床诊治和区域性防控工作的进行提供了理论依据和指导。     

新疆阿勒泰地区绵羊弓形虫病的血清学调查

为了解新疆阿勒泰地区绵羊弓形虫病的感染情况以及感染弓形虫病与绵羊流产的关系,对阿勒泰地区6县1市的绵羊随机采集血清共565份,采用间接血凝试验进行了弓形虫感染的血清学检测。结果显示,阿勒泰地区各县(市)绵羊均有弓形虫感染,感染率高低不一,平均感染率为6.5%;在有流产史的绵羊中发现存在布鲁菌和弓形虫双重感染的情况,提示在预防和治疗绵羊流产时,除了要考虑布鲁菌感染的因素以外,还应考虑弓形虫感染这一因素。     

香根草根际AM菌的感染特性

通过对不同种植时间、不同种植基质的香根草Vetiveria zizanioides分株苗、组培苗根际丛枝菌根(AM菌)感染检测,探讨了香根草对AM菌的感染特性.结果表明,在消过毒的森林泥炭土中,组培苗种植12个月感染率只有20.0%,感染强度低;种植22个月只有53.3%,感染强度为中.分株苗种植在自然土壤中,3个月就有AM菌感染,其感染率为56.7%;种植22个月感染率达到最高峰,为80.0%,感染强度为中等;种植时间为33个月时,感染率不再增加,但感染强度进一步增高.说明香根草根际AM菌的感染率和感染强度可能与苗源无关,而与种植基质密切相关.     

动物园草食动物肠道寄生虫感染情况和治疗效果回顾性分析

应用离心沉淀法和饱和蔗糖溶液漂浮法对郑州市动物园22种草食动物共88份粪便样品进行调查。寄生虫总感染率为19.31%,球虫、线虫和鞭虫感染率分别为7.95%、12.50%和2.27%。数据分析显示,寄生虫感染率逐年递减,比2003年降低了39.95%,感染程度也明显减轻。表明该园防控措施具有良好效果,为今后动物园制定有关寄生虫病防治措施提供了参考依据。