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1.
Liu YJ Li ZQ Hao YH 《Journal of veterinary medicine. B, Infectious diseases and veterinary public health》2002,49(8):371-372
In vitro-hatched oncospheres of Taenia solium, prepared by the sodium hypochlorite method and adjusted to approximately 5 x 10(2)/2ml phosphate buffer saline, were injected intramuscularly or intravenously into normal Balb/c mice. When these mice were sacrificed 2 months later, all cysticerci were exclusively recovered in the lungs from the mice with intravenous inoculation, but not with intramuscular injection. A high infection rate of 76% was obtained and a total of 45 cysticerci were collected from 50 mice. Thirty-five cysticerci were mature and with normal appearance but the rest were either with abnormal appearance (4) or degenerated (6). These findings give strong evidence that T. solium oncospheres may migrate to the normal mouse lung through venous circulation and develop in this organ. 相似文献
2.
Taenia solium oncosphere antigens induce immunity in pigs against experimental cysticercosis 总被引：11，自引：0，他引：11
Verastegui M Gilman RH Gonzales A Garcia HH Gavidia C Falcon N Bernal T Arana Y Tsang VC;Cysticercosis Working Group In Peru 《Veterinary parasitology》2002,108(1):49-62
Immunity to Taenia solium infection was investigated using an experimental intramuscular oncosphere infection assay (IMOA) model in pigs. Three naturally infected pigs with cysticercosis were treated with oxfendazole (OFZ), a drug demonstrated to kill cysts in porcine muscle. These animals were then challenged with oncospheres but did not develop any cysts while three uninfected pigs that were similarly challenged, did develop intramuscular cysts. In another study, two groups of three pigs each were immunized with crude T. solium oncosphere and metacestode antigens, respectively, and tested with the IMOA. Immunization with crude oncosphere antigens (OAs) induced 100% protection, while metacestode antigens provided only partial protection. Immunoblots showed that pigs with complete immune protection to oncosphere intramuscular challenge had antibodies to two OAs at 31.3 and 22.5 kDa, respectively. Antibody to these two antigens was absent in pigs immunized with metacestodes or in uninfected control pigs. This study demonstrated the presence of two antigens that are unique to the oncosphere. Although, antibody to these two antigens is consistently present in pigs that are protected from an oncosphere intramuscular challenge their role in preventing infection by T. solium larval cysts is still hypothetical. 相似文献
3.
Chapalamadugu KC Busboom JR Nelson ML Hancock DD Tang J Jasmer DP 《Veterinary parasitology》2008,151(2-4):203-211
Methods to determine viability of taeniid oncospheres following treatments with potential lethality have practical application in efforts to control transmission. Here we investigated several methods, in lieu of infectivity studies, to assess oncosphere viability and determine lethal temperature treatment regimens. In the first experiment, a standard treatment to exshell oncospheres with 0.5% hypochlorite was assessed for influence on oncosphere recovery of Taenia taeniaeformis eggs. Recovery of eggs and exshelled oncospheres decreased with increasing time in hypochlorite, which indicated that hypochlorite can damage eggs and oncospheres, translating into potential overestimation of lethality of experimental treatments. Losses in hypochlorite were accentuated when eggs were pretreated at 75 degrees C, but not lower temperatures, including 65 degrees C, indicating a sharp threshhold between 65 degrees C and 75 degrees C where eggs and oncospheres became hypersensitive to subsequent hypochlorite treatment. To further investigate this change in relation to temperature, non-vital (acridine orange, AO) and vital (propidium iodide, PI; trypan blue, TB) dyes were used to assess staining of oncospheres (exshelled or not) under conditions ranging from room temperature up to 95 degrees C. The behaviors of dyes as related to internal staining of oncospheres were described using non-linear regression and a sigmoid four-parametric model to determine the inflection point (T50). Each of the dyes differed significantly in T50 estimates, e.g. AO (69.22+/-0.53), PI (73.89+/-0.52) and TB (79.43+/-0.45). For these dyes, the T50 increased in relation to the increasing molecular weight of the dyes. Collectively, the results suggested that barriers to chemical permeability exist in eggs that breakdown incrementally with increasing temperatures above 65 degrees C. This staining behavior and the likelihood that the temperatures involved are above a lethal threshhold clarify a basic limitation in the use of vital dyes to assess oncosphere viability. The results may be relevant to other Taenia spp. 相似文献
4.
Zimic M Pajuelo M Gilman RH Gutiérrez AH Rueda LD Flores M Chile N Verástegui M Gonzalez A García HH Sheen P;Cysticercosis Working Group in Peru 《Veterinary immunology and immunopathology》2012,145(1-2):171-178
Cathepsin L-like proteases are secreted by several parasites including Taenia solium. The mechanism used by T. solium oncospheres to degrade and penetrate the intestine and infect the host is incompletely understood. It is assumed that intestinal degradation is driven by the proteolytic activity of enzymes secreted by the oncosphere. Blocking the proteolytic activity by an antibody response would prevent the oncosphere penetration and further infection. Serine and cysteine proteases including chymotrypsin, trypsin, elastase, and cathepsin L, are secreted by T. solium and Taenia saginata oncospheres when cultured in vitro, being potential vaccine candidates. However, the purification of a sufficient quantity of proteases secreted by oncospheres to conduct a vaccine trial is costly and lengthy. A 53/25 kDa cathepsin L-like fraction partially purified from T. solium cyst fluid was described previously as an important antigen for immunodiagnostics. In this study we found that this antigen is present in the T. solium oncosphere and is also secreted by the cysticercus. This protein fraction was tested for its ability to protect pigs against an oral challenge with T. solium oncospheres in a vaccine trial. IgG antibodies against the 53/25 kDa cathepsin L-like protein fraction were elicited in the vaccinated animals but did not confer protection. 相似文献
5.
Attempted infection of calves with Taenia crocutae cysticerci and their subsequent serological response 总被引：1，自引：0，他引：1
The susceptibility of naive cattle to infection with cysticerci of Taenia crocutae was tested using three six- to nine-month-old Ayrshire bull calves, previously unexposed to infection with taeniid eggs. One calf was given 10,000 T crocutae eggs orally, another 5000 hatched unactivated oncospheres orally and the third 5000 hatched and activated oncospheres by intravenous injection. None of the calves contained viable cysticerci at post mortem examination 15 to 17 weeks later. All three calves contained small numbers of lesions in the liver and lesions were also present in the lungs of the calf which received oncospheres intravenously. All the calves developed an antibody response which was most pronounced in the calf given hatched unactivated oncospheres orally. 相似文献
6.
I Jelenová 《Veterinární medicína》1991,36(5):291-296
The survival of Moniezia expansa eggs in the droppings of lambs was investigated at various temperatures in laboratory conditions and on test plots outdoors. The optimum temperature of the livability of M. expansa eggs in laboratory conditions is 5 degrees C; at this temperature 10% of oncospheres survived after 161 days. At the temperatures of 10, 25, 35 degrees C the oncospheres survived 105, 28, 46 days respectively, at -12 degrees C it was 28 days. It was for 21 and 35 days that on the test grassy plots the eggs of M. expansa survived in the droppings of lambs in the summer months of July and August at the average air temperatures of 15.7-18.2 degrees C and relative humidity of 67.7-74.3%. In autumn in September and October, at the average temperatures of 5.8-14.6 degrees C and relative humidity of 65.3-76.7% the oncospheres survived for 49 to 91 days. The M. expansa eggs in the droppings of lambs were able to survive on the test plot. The living oncospheres were demonstrated for 119 days from November 1987 to March 1988, and for 175 days till May by means of experimental infection of intermediate hosts. 相似文献
7.
Previously described techniques for hatching eggs ofTaenia taeniaeformis were found to give inconsistent and generally ineffective results, even the degree of disaggregation of the embryophore varying with the strain of parasite. Furthermore, the hatched and activated oncospheres did not survive in the hatching fluid.Following a series of studies on the composition of the hatching fluids, a more reliable procedure was developed.Pretreatment with hypochlorite, at 0.67% w/w available chlorine, caused disaggregation of the embryophoral blocks of virtually all the eggs. When this was followed by exposure to a solution containing 10 mg.ml–1 trypsin, 10% ox bile and 10% heat-inactivated foetal calf serum in modified RPMI with HEPES buffer and L-glutamine, about 50% of the viable oncospheres were activated and escaped from the oncospheral membrane. Most of the activated oncospheres survived in this hatching fluid for at least three hours. 相似文献
8.
Taenia saginata oncosphere components were analysed by double diffusion. Antigenic components in saline or detergent (Triton x-100) extracts of T saginata oncospheres were identified using a rabbit polyclonal serum directed against the oncosphere and compared with extracts prepared from the metacestodes and proglottids of T saginata and six other helminths commonly found in cattle. There were seven antigenic components found in the saline extract of the oncospheres, of which six were shared with the metacestodes and proglottids. None of these components was consistently different from those of the other six helminths. However, one of the four components in the detergent extract of the oncospheres was present in neither of the extracts of other stages of T saginata nor in extracts of other helminths. This may be of diagnostic significance. 相似文献
9.
Viable eggs or activated oncospheres of Taenia pisiformis were inoculated subcutaneously into rabbits. At various intervals the developing larvae were killed by treatment with Mebendazole. Most rabbits receiving oncospheres were protected against challenge infection if they were treated with Mebendazole 1 day after injection and absolute immunity was established in all rabbits if larvae were allowed to develop for 14 days before being killed. In rabbits receiving eggs, 21 days from injection to Mebendazole treatment was required before absolute immunity developed. Eggs appear to require a period of 1–2 weeks for hatching and oncosphere activation in a subcutaneous site. The data also indicate that production of functionally protective antigens occurs early during larval developement. 相似文献
10.
Proteins present in oncospheres and on the surface of living protoscoleces of Echinococcus granulosus were radioiodinated by the lodogen technique and immunoprecipitated with sera from dogs with E granulosus infection and several categories of control sera. Analysis of immunoprecipitates was performed using sodium dodecyl-sulphate polyacrylamide gel electrophoresis to identify antigenic protein components specific for E granulosus. Sera from dogs with E granulosus infection identified antigenic proteins of around Mr 37,000, 30,000 or 22,000 in oncospheres, and proteins of around Mr 70,000, 43,000, 36,000, 27,000 (triplet), 20,000 or 14,000 on the surface of protoscoleces. These antigens appear to be both species- and stage-specific and may be useful for serological discrimination between 'current' and 'recent past' prepatent and patent E granulosus infections in dogs. 相似文献
11.
异源性抗原抗猪囊尾蚴感染的研究 总被引：1，自引：0，他引：1
本文报道了泡状带绦虫活化六钩蚴的超声裂解抗原可以诱导猪体产生抗猪带绦虫攻击感染的交叉保护作用。猪囊尾蚴匀浆抗原也使猪体产生了较强的抗猪带绦虫攻击感染的保护作用。泡状带绦虫六钩蚴超裂抗原免疫组与猪囊尾蚴匀浆抗原免疫组的保护情况是相似的,这表明异源免疫也可使猪体产生较好的抗猪囊尾蚴感染的免疫。由于制备异源性抗原的泡状带绦虫能够从狗的体内获得,因此在体外培养猪带绦虫未获成功之前可以解决从人体获取猪带绦虫的困难。 相似文献
12.
本研究目的在于制备抗猪带绦虫TSOL18单克隆抗体,并分析单抗对六钩蚴的杀伤作用。采用SephadexG-100纯化在毕赤酵母中表达的猪带绦虫六钩蚴TSOL18蛋白;纯化的蛋白免疫BALB/c小鼠,运用杂交瘤技术建立能分泌抗TSOL18单克隆抗体的细胞株;通过ELISA叠加试验进行mAb的抗原表位分析;采用间接ELISA法测定TSOL18单克隆抗体特异性及腹水效价;采用抗TSOL18单克隆抗体对激活的猪带绦虫六钩蚴进行体外六钩蚴杀伤试验,观察单抗对猪带绦虫六钩蚴活力的影响。结果成功获得12株稳定分泌抗TSOL18单克隆抗体的杂交瘤细胞株,识别2个不同抗原表位,不同抗原表位的2株单克隆抗体腹水效价分别为1×102、1×106。抗体体外六钩蚴杀伤试验结果证明,在有补体的情况下,多抗和单抗作用6 d后,六钩蚴结构模糊,边缘不清晰。表明单抗对六钩蚴有一定的杀伤作用。 相似文献
13.
Ciarmela ML Thevenet PS Alvarez HM Minvielle MC Basualdo JA 《Veterinary parasitology》2005,131(1-2):61-64
Paecilomyces lilacinus (Thom) Samson is a saprophytic hyphomycete from the soil with biological activity on helminth eggs. We evaluated the influence in vitro of P. lilacinus on the viability of the oncospheres from Taenia hydatigena, a parasite cestode of dogs and sheep. The eggs were exposed to the fungus strain in sterile distilled water and observed by light microscopy at days 4, 7 and 14 post-inoculation, and the viability was evaluated. The viability found in the exposed P. lilacinus oncospheres was significantly different in all observations. P. lilacinus exercised a negative biological activity on T. hydatigena eggs in vitro. 相似文献
14.
Passive transfer of immunity to neonatal calves against Taenia saginata was examined. Immune serum immunoglobulins were obtained from cattle inoculated orally with eggs of T. saginata, and from an animal which had been injected intramuscularly with eggs and activated oncospheres of the parasite. Immune colostral immunoglobulins were obtained by local injection of the mammary gland of a preparturient cow using activated oncospheres of T. saginata as antigen.Newborn calves fed the immune serum or colostral immunoglobulins were significantly protected against infection with T. saginata. In addition, more than 80% of the metacestodes in the protected calves showed evidence of degeneration, while only 34 and 27% of the metacestodes showed evidence of degeneration in those animals receiving “normal” control serum and “normal” control colostral immunoglobulins, respectively. 相似文献
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16.
肌内脂肪在骨骼肌中的含量包括长背肌,也称为大理石花纹脂肪,是决定牛肉质量最重要的因素之一。基因、品种、管理和营养影响肌内脂肪沉积。在此,本文综述了影响肌内脂肪沉积的遗传因素(品种、性别差异和遗传力)和管理因素。阉割公牛会增加大多数品种牛的肌内脂肪沉积。本文还综述了断奶日龄、阉割、屠宰体重、年龄和环境条件等因素对肌内脂肪沉积的影响。营养因素包括脂肪代谢,饲料消化、吸收,葡萄糖、淀粉的有效性,维生素水平。因此,根据消费者对牛肉的偏好,可能需要多种策略的组合来调控肌内脂肪的沉积。 相似文献
17.
A preliminary report onMeriones unguiculatus as an experimental host forTaenia saginata metacestodes
Jirds (Meriones unguiculatus) were treated with dexamethasone and inoculated subcutaneously with 100–300 oncospheres ofTaenia saginata. Ten of the jirds received 0.5 mg of the drug per animal twice weekly during the first month after inoculation and then once a week until necropsy and four of these became infected. Up to 20 viable metacestodes were recovered in the subcutaneous tissue at the site of inoculation three months after infection. 相似文献
18.
An experiment was carried out using five groups of five beagle puppies each to measure age resistance to T. pisiformis infection and acquired immunity resulting from exposure to antigens released by adult tapeworms and/or oncospheres. Resistance was gauged by the number of worms established from challenge infections, and by the degree of development of those worms established (relaxed lenght, segment number, eggs per terminal proglottis).Age of puppies had a marked effect upon worm development, excluding the number of eggs per terminal proglottis, but not upon the number of worms established. Acquired immunity could not be demonstrated by any of the methods used. 相似文献
19.