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   

Small-scale forestry development in Leyte,Philippines: The central role of nurseries     

Nestor Gregorio  John Herbohn  Steve Harrison 《Small-Scale Forestry》2004,3(3):337-351

This paper presents results of survey research into the role of the forestry nursery sector in the development of smallholder forestry in Leyte, Philippines. Seedling production in the province is basically carried out by three categories of nurseries: individual, communal and the government. Seedlings in the government nurseries are primarily raised for free distribution to landholders but the extension scheme fails to reach the majority of the smallholder farmers. Seedling demand of landholders is mostly catered for by the more numerous and accessible individual and communal nurseries. However, problems of capital outlay, sources and supply of germplasm, technical knowledge in nursery management for both timber and fruit trees and low sales are among the major impediments in the sustainability of small-scale nurseries. Most of the communal nurseries fail to sustain the operation after the withdrawal of supporting agencies. Knowledge on site-species matching is needed not only by small-scale nursery operators but also by the managers of government nurseries. It is concluded that the seedling industry in the province is not well established and there is a need to organise better the overall nursery system so as to improve the availability of seedlings and promote appropriate site and species combinations.  相似文献   

Edge type determines the intensity of forest edge effect on epiphytic communities     

Gregorio Aragón  Laura Abuja  Rocío Belinchón  Isabel Martínez 《European Journal of Forest Research》2015,134(3):443-451

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Development and Implementation of a Forest Nursery Accreditation Policy at a Local Level in Leyte, Philippines     

Rotacio S. Gravoso  Nestor O. Gregorio  Maria Anabelle D. Gerona  Moises Neil V. Seri?o  Steve R. Harrison  Herville V. Pajaron  Jayson V. Godoy 《Small-Scale Forestry》2011,10(4):473-488

Through a series of workshops with the stakeholders including nursery operators, tree farmers, staff of the Department of Environment and Natural Resources, local government units and the academe, a forestry seedling nursery accreditation policy was developed. The resulting policy was subsequently implemented by the municipal government of Palompon, Leyte. The accreditation policy encouraged nursery operators to follow smallholder-based best management practices for tree nurseries. Implementation of the nursery accreditation policy improved farmers’ knowledge and skills in the production of high quality seedlings, encouraged adoption of BMP for forest nurseries, provided additional source of income for the farmers, enabled members of the groups operating the communal nursery to forge closer relationship with each other, encouraged utilization of farmers’ free time in productive activities, developed farmers’ confidence in producing high quality planting materials, and gained for the farmers favourable attention from various organizations and groups. The Bennett’s hierarchy of project outcomes showed that the implementation of accreditation scheme achieved high levels of outcomes, indicating that it led to substantial improvements in the lives of the farmers.  相似文献   

Effect of source germplasm and season on the in vivo haploid induction rate in tropical maize     

Aida Z. Kebede  Baldev S. Dhillon  Wolfgang Schipprack  Jose L. Araus  Marianne Bänziger  Kassa Semagn  Gregorio Alvarado  Albrecht E. Melchinger 《Euphytica》2011,180(2):219-226

For in vivo production of doubled haploid (DH) lines in maize, the rate of haploid induction is of crucial importance. Maternal haploid induction depends primarily on the inducer used as a pollinator. However, the source germplasm used as a maternal parent and the environmental conditions for induction may also influence haploid induction and these aspects have not been examined in tropical maize so far. The objectives of our study were to (i) monitor the variation for haploid induction rate (HIR) among diverse source germplasm in tropical maize, (ii) determine the relative importance of general (GCA) and specific (SCA) combining abilities for HIR, and (iii) investigate the influence of summer and winter seasons and genotype × season interactions on this trait. Ten inbreds were mated in a half diallel design. The resulting 45 F₁ single crosses were pollinated with the haploid inducer hybrid RWS × UH400 during the summer 2008 and winter 2009 seasons in a lowland tropical environment in Mexico. HIR of the single crosses averaged over seasons ranged from 2.90 to 9.66% with an overall mean of 6.74%. Mean HIR was significantly (P < 0.01) higher during the winter (7.37%) than summer season (6.11%). Significant (P < 0.01) variation was observed due to GCA effects of parental inbreds of single crosses but not for SCA, GCA × season and SCA × season interactions. Our study underpins that a higher HIR in tropical maize can be obtained by selecting appropriate source germplasm and undertaking pollination under favorable environmental conditions.  相似文献   

Uphill road for new drugs     

J O Nestor  W J Lipton 《Science (New York, N.Y.)》1969,166(913):1575-1576

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Origin and evolution of prebiotic organic matter as inferred from the Tagish Lake meteorite     

Herd CD  Blinova A  Simkus DN  Huang Y  Tarozo R  Alexander CM  Gyngard F  Nittler LR  Cody GD  Fogel ML  Kebukawa Y  Kilcoyne AL  Hilts RW  Slater GF  Glavin DP  Dworkin JP  Callahan MP  Elsila JE  De Gregorio BT  Stroud RM 《Science (New York, N.Y.)》2011,332(6035):1304-1307

The complex suite of organic materials in carbonaceous chondrite meteorites probably originally formed in the interstellar medium and/or the solar protoplanetary disk, but was subsequently modified in the meteorites' asteroidal parent bodies. The mechanisms of formation and modification are still very poorly understood. We carried out a systematic study of variations in the mineralogy, petrology, and soluble and insoluble organic matter in distinct fragments of the Tagish Lake meteorite. The variations correlate with indicators of parent body aqueous alteration. At least some molecules of prebiotic importance formed during the alteration.  相似文献   

Ultrastructure of Giardia canis trophozoites     

M Inês  T L Sogayar  E A Gregorio 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1984,31(2):107-114

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Influence of mass of ruminal contents on voluntary intake and digesta passage in steers fed a forage and a concentrate diet     

Whetsell MS  Prigge EC  Nestor EL 《Journal of animal science》2004,82(6):1806-1817

To evaluate the influence of mass of ruminal contents on voluntary intake and ruminal function, five ruminally cannulated steers (550 kg) were fed an orchard grass hay diet ad libitum in a 5 x 5 Latin square experiment. The mass of ruminal contents was altered by adding varying weights of modified tennis balls to the rumen before the initiation of each 15-d experimental period. Treatments consisted of 50 balls with a specific gravity of 1.0, 1.1, 1.2, 1.3, or 1.4; the total weight of the balls was 7.45, 8.50, 9.25, 10.55, and 11.55 kg, respectively. Increasing the specific gravity of the balls added to the rumen decreased DMI and particle passage rate (P < 0.05) in a linear manner. A second experiment was conducted to evaluate the influence of mass of ruminal contents on voluntary intake and ruminal function of both forage and concentrate diets. Five ruminally cannulated steers (580 kg) were fed a 70% concentrate (DM basis) or an orchardgrass hay diet ad libitum in a 5 x 5 Latin square experiment. The mass of ruminal contents was altered as in the first experiment. Treatments consisted of 0 balls added to the rumen of steers fed concentrate diet (control), 75 balls with a specific gravity of 1.1 given to steers fed a concentrate diet, 75 balls with a specific gravity of 1.4 given to steers fed a concentrate diet, 75 balls with a specific gravity of 1.1 given to steers fed a hay diet, and 75 balls with a specific gravity of 1.4 given to steers fed hay diet. The addition of balls to the rumen of steers fed the concentrate diet decreased DMI (P < 0.05) compared with the 0-ball treatment, and increasing specific gravity of balls also decreased DMI (P < 0.01) for both concentrate and hay diets. Adding balls to the rumen of steers fed the concentrate diet decreased particle passage rate (P < 0.05), whereas increasing specific gravity of balls decreased particle passage rate for both concentrate and hay diet. The results of this study suggest that the density of ruminal digesta can have an influence on voluntary intake of both forage and concentrate diets.  相似文献   

Correlation of magnetic resonance images with anatomic features of the equine tarsus     

Latorre R  Arencibia A  Gil F  Rivero M  Henry RW  Ramírez G  Váquez JM 《American journal of veterinary research》2006,67(5):756-761

OBJECTIVE: To correlate anatomic features of the equine tarsus identified in plastinated sections with images obtained via magnetic resonance imaging (MRI). ANIMALS: 4 horses. PROCEDURE: MRI (1.5-Tesla magnet) of the tarsus was performed on the pelvic limbs of 4 clinically normal horses following euthanasia. After imaging, tarsocrural joint spaces and vasculature were injected with colored latex. Sagittal and transverse sections of the tarsi were plastinated to facilitate interpretation of MR images. RESULTS: Relevant anatomic structures were identified and labeled on the plastinated tissue slices and corresponding MR images. Results indicated high correlations between MRI findings and those of plastinated sections. CONCLUSIONS AND CLINICAL RELEVANCE: The data obtained provided certain reference standards for normal anatomic structure sizes and positions in the equine tarsus. This information may aid future physiologic or clinical studies of this joint.  相似文献