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1.
In northern Pakistan, many farming communities rely on domestic yak (Bos grunniens) as a principle source of income. A 2006 participatory disease surveillance report from this region indicated that foot-and-mouth disease (FMD) is the most prevalent annual disease of yak. Our objectives of this study were to determine exposure levels of yak to FMD virus; implement a vaccination program based on current, regional FMD virus serotypes and subtypes; and quantify immune responses following vaccination. Blood samples were used to determine pre-vaccination exposure of animals to FMD virus by antibody presence to non-structural proteins of FMD virus using a 3-ABC trapping indirect ELISA. Vaccine used consisted of FMD serotypes ‘O’ (PanAsia-2), ‘A’ (Iran-05), and ‘Asia-1’ (Shamir), but changed later during the study to match newly circulating viruses in the country (‘O’-PanAsia-2; ‘A’-Turk-06 and Asia-1-Sindh-08). Three hundred sixty-three blood samples were tested from selected villages to determine pre-vaccination FMD virus exposure in yak with an average of 37.7%. Immune responses from initial vaccination and booster dose 30 days later showed clear protective levels (as mean percent inhibition) of antibodies against structural proteins of serotypes ‘O,’ ‘A,’ and ‘Asia-1.’ These responses remained above threshold positive level even at day 210 following initial vaccination. Results of sero-surveillance and anecdotal information of repeated FMD outbreaks demonstrate the persistence of FMD virus of yak in northern Pakistan. Laboratory results and field observations clearly indicated that yak can be protected against FMD with a good quality vaccine with FMD serotype(s) matching current, regionally circulating FMD virus.  相似文献   
2.
Interferon (IFN)-γ has been shown to be associated with immunity to Marek’s disease virus (MDV). The overall objective of this study was to investigate the causal relationship between IFN-γ and vaccine-conferred immunity against MDV in chickens. To this end, 3 small interfering RNAs (siRNAs) targeting chicken IFN-γ, which had previously been shown to reduce IFN-γ expression in vitro, and a control siRNA were selected to generate recombinant avian adeno-associated virus (rAAAV) expressing short-hairpin small interfering RNAs (shRNAs). An MDV challenge trial was then conducted: chickens were vaccinated with herpesvirus of turkey (HVT), administered the rAAAV expressing shRNA, and then challenged with MDV. Tumors were observed in 4 out of 10 birds that were vaccinated with HVT and challenged but did not receive any rAAAV, 5 out of 9 birds that were administered the rAAAV containing IFN-γ shRNA, and 2 out of 10 birds that were administered a control enhanced green fluorescent protein siRNA. There was no significant difference in MDV genome load in the feather follicle epithelium of the birds that were cotreated with the vaccine and the rAAAV compared with the vaccinated MDV-infected birds. These results suggest that AAAV-based vectors can be used for the delivery of shRNA into chicken cells. However, administration of the rAAAV expressing shRNA targeting chicken IFN-γ did not seem to fully abrogate vaccine-induced protection.  相似文献   
3.
Journal of Crop Science and Biotechnology - India has a diverse range of agro-ecological conditions which support the cultivation of different rice varieties differing in the adaptation which is so...  相似文献   
4.
近年来兴起的病毒基因组或部分目的基因以及蛋白表达分析技术,为人们更好地认识宿主对马立克氏病病毒(MDV)的免疫应答机制提供了有利帮助.本文主要综述了从转录组学和蛋白质组学开展的有关MDV致病机理、宿主对MDV反应、MD遗传抗性或易感性以及疫苗诱导的免疫反应等方面的最新研究进展,并讨论了应用miRNA以及RNAi技术对基因、蛋白和信号通路在MDV与宿主相互作用中发挥重要作用的效应单位进行功能分析.  相似文献   
5.
The present investigation describes detection of a mammalian-like electropherogroup A rotavirus in chicken with diarrhoea. This also records the first detection of a rotavirus in an avian species from India. During the investigation 75 diarrhoeic faecal samples collected from adult chicken were screened for the presence of group A rotavirus antigen by sandwich ELISA. All three samples positive for rotavirus antigen revealed 11 bands of RNA in polyacrylamide gel electrophoresis (PAGE). In contrast to avian group A rotavirus, segment 5 was found to migrate closer to 6 as is the case with mammalian group A rotaviruses. Segments 7, 8 and 9 were found to migrate as a tight triplet, which is characteristic of group A rotavirus.  相似文献   
6.
Sissoo (Dalbergia sissoo), commonly known as shisham, is amongst the finest woods of South Asia, but ‘wilt’ disease has caused a rapid decline in this species. The cause of the disease remains uncertain. The aim of this study is to identify the causal agent of the disease and characterize isolates made from diseased trees, based on genomic data and variations in virulence. Samples of infected roots, stems and the ooze exuded from infected trees were obtained from plants showing symptoms in different geographical regions of India for the isolation of microorganisms. Isolates were used to inoculate healthy plants. Based on the morphological characteristics, genus‐ and species‐specific PCR, and in silico analysis of 5.8S rDNA‐ITS regions, of the 38 fungal isolates, 24 and 14 were identified as Fusarium solani and Fusarium sp., respectively. In a pathotyping study, eighteen F. solani isolates, isolated from roots and stem parts of symptomatic plants, induced typical wilt symptoms when inoculated through soil and roots on D. sissoo seedlings of 1–15 months in age. The population of F. solani was the highest in infected roots and the lowest in parts of stems, gradually decreasing with height, and was isolated constantly up to approximately 40% height of the seedling. F. solani isolates used in inoculations were successfully re‐isolated from the rhizosphere, infected roots and wilted stems, as confirmed using isolate‐specific DNA fingerprints. Molecular phylogenies based on rDNA‐ITS sequences showed that the 38 isolates fell into 2 groups. Group I comprised of F. solani isolates from D. sissoo and F. solani sequences in the NCBI GenBank database, whereas group II included Fusarium isolates other than F. solani. These results are helpful in developing integrated control measures for this highly variable pathogen and to establish a base for future population studies.  相似文献   
7.
The baobab tree (Adansonia digitata L.) is a valued savannah tree. Although variation in fruit characteristics of this tree have been studied, no studies to our knowledge have been carried out on variation of leaf morphology which can be linked to drought adaptation mechanisms. Accessions of baobab from different ecosystems in Benin were characterised for leaf size and thickness, stomata size and density on the abaxial surface of leaves. Significant variation was found in leaf size and stomata characteristics. Trees from northern study sites had higher stomata density and smaller guard cell length than those from southern study sites. The results show that pruning has a significant effect on leaf size, but not on stomatal characteristics. Trees from northern study sites showed more xerophytic characteristics than those from the south. It seems that genetic and physiological effects may play a role in baobab drought adaptation.  相似文献   
8.
OBJECTIVE: To evaluate compliance with the World Health Organization's International Code of Marketing of Breast-milk Substitutes in primary care, after the introduction of strict local infant feeding guidelines. DESIGN: An audit form was sent to all community-based health professionals with an infant feeding remit. Walking tours were conducted in a random sample of community care facilities. SETTING: Greater Glasgow Primary Care Division. SUBJECTS: (1) Primary-care staff with an infant feeding remit; (2) community health-care facilities. MAIN OUTCOME MEASURES: Contact with manufacturers of breast-milk substitutes (BMS) and BMS company personnel, free samples or incentives, and advertising of BMS. RESULTS: Contact with company personnel was minimal, usually unsolicited and was mainly to provide product information. Free samples of BMS or feeding equipment were rare but childcare or parenting literature was more prevalent. Staff voiced concerns about the lack of relevant information for bottle-feeding mothers and the need to support the mother's feeding choice. One-third of facilities were still displaying materials non-compliant with the Code, with the most common materials being weight conversion charts and posters. CONCLUSIONS: Contact between personnel from primary care and BMS companies was minimal and generally unsolicited. The presence of materials from BMS companies in health-care premises was more common. Due to the high level of bottle-feeding in Glasgow, primary-care staff stated a need for information about BMS.  相似文献   
9.
The pulp left after the extraction of juice from Citrus reticulate (kinnow), is a waste material, which was used as a potential sorbent for Cr(III) and Cr(VI) in the present study. The effect of experimental parameters such as pH, biosorbent dosage, biosorbent particle size, initial metal concentrations, temperature, shaking speed and sorption time on the Cr removal is apparent from the obtained results. The Freundlich isotherm and pseudo second order kinetic models fitted well to the data of Cr(III) and Cr(VI) biosorption by Citrus reticulata waste biomass. Effect of several pretreatments such as gases, natural coagulant and many other chemicals on Cr(III) and Cr(VI) sorption capacity of Citrus reticulata waste biomass was first time analyzed in the present study. The metal sorption capacity of Citrus reticulata waste biomass after a specific pretreatment was not only related to the nature of chemical but also strongly dependent on the oxidation state of the metal.  相似文献   
10.
Chronology of fluctuating sea levels since the triassic   总被引:19,自引:0,他引:19  
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