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The eukaryotic expression plasmid of M2e-Hsp70 is a candidate M2e-based DNA vaccine. In order to evaluate the immunization potential of this construct, Specific Pathogen Free chickens were immunized either intramuscularly or orally. Mutant Salmonella typhimurium was used as carrier for oral delivery of the M2e-Hsp70 construct. M2e-specific humoral and cellular responses were tested by ELISA and Lymphocyte Proliferation Assay, respectively. Our results indicate that both humoral and cellular immune responses are conferred against M2e-Hsp70 plasmid in either of the intramuscular or oral routes of administration; however, these responses are significantly higher in intramuscular injection in contrast to oral administration. When it comes to mass vaccination of commercial chicken flocks oral administration is preferred due to the ease of application as well as its capability of eliciting mucosal, humoral and cellular immune responses; so measurements should be taken to improve the immunization potency of our orally delivered DNA vaccine.  相似文献   
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The giant fresh water prawn Macrobrachium rosenbergii is known to be highly tolerant to white spot syndrome virus (WSSV) infections when compared to the widely cultured marine tiger shrimp Penaeus monodon. At present, the exact mechanism of tolerance by M. rosenbergii to WSSV is not known. In this study, we attempt to study the effect of WSSV injections on the hemagglutination activity of the hemolymph serum of both P. monodon and M. rosenbergii and look for changes if any, on their hemolymph serum protein electrophoretic patterns. Our results show that M. rosenbergii had significantly (p < 0.05) higher hemagglutinating activity against mouse erythrocytes when compared to P. monodon. As the infection progressed to 48 h there was a further increase (p < 0.05) in the hemagglutination activity in M. rosenbergii, while it decreased in P. monodon. 12% SDS-PAGE analysis of the hemolymph serum of M. rosenbergii infected with WSSV did not show any new protein bands, whereas few bands with decreased intensity was observed in moribund P. monodon where the hemagglutinating activity was also observed to be decreased. The results indicate that hemolymph hemagglutinin levels are modulated in crustaceans as a response to viral infections.  相似文献   
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BACKGROUND: RNA interference (RNAi) is a breakthrough technology for conducting functional genomics studies and also as a potential tool for crop protection against insect pests. The major challenge for efficient pest control using RNAi in the field is the development of efficient and reliable methods for production and delivery of double‐stranded RNA (dsRNA). In this paper, the potential of feeding dsRNA expressed in bacteria or synthesized in vitro to manage populations of Colorado potato beetle, Leptinotarsa decemlineata (Say) (CPB), was investigated. RESULTS: Feeding RNAi successfully triggered the silencing of all five target genes tested and caused significant mortality and reduced body weight gain in the treated beetles. This study provides the first example of an effective RNAi response in insects after feeding dsRNA produced in bacteria. CONCLUSION: These results suggest that the efficient induction of RNAi using bacteria to deliver dsRNA is a possible method for management of CPB. This could be also a promising bioassay approach for genome‐wide screens to identify effective target genes for use as novel RNAi‐based insecticides. Copyright © 2010 Society of Chemical Industry  相似文献   
5.
Ovar-DRB1 is one of the most important response genes in the major histocompatibility complex (MHC) class II region of sheep. Gene polymorphism in the second exon of Ovar-DRB1 in three different Iranian fat-tailed sheep breeds (Lori-Bakhtiari, Shaul and Zandi) was analyzed by either restriction fragment length polymorphisms (RFLP) or direct sequencing. A total of 92 Lori-Bakhtiari, 40 Shaul, and 47 Zandi sheep were examined. PCR-RFLP identified 17 genotypes in Lori-Bakhtiari sheep, 12 in Shaul sheep and 11 in Zandi sheep. Collectively, 24 different genotypes could be found for Iranian fat-tailed sheep. Using direct sequencing, seven new sequences in exon 2 of the Ovar-DRB1 gene were identified. Generalized linear modeling with a multinomial error structure showed that the sheep populations had significantly different allele frequencies.  相似文献   
6.
Reptile contact can result in zoonotic non‐typhoidal salmonellosis. In April 2018, Oregon Public Health Division contacted CDC about a cluster of four Salmonella serovar Fluntern (SF) illnesses in four states (OR, CA, IA, NY); patients reported contact with geckos, a popular reptile pet. PulseNet, the national molecular subtyping network of food‐borne disease surveillance, subsequently identified additional SF clinical isolates. Twelve cases in 11 states were identified; median age was 5 years (range: <1–58 years). Three patients were hospitalized; no deaths were reported. Of those with exposure information (n = 10), all reported reptile exposure; 9 (90%) specified contact with leopard geckos. No common source of geckos was identified from reported purchase locations. Los Angeles County (LAC) health officials isolated SF from one patient's leopard gecko. Five reptile/gecko isolates were identified from the USDA National Veterinary Services Laboratories (NVSL) from 2015 to 2018. Five countries responded to an Epidemic Intelligence Information System post by PulseNet; reptile isolate sequence data were received from Czech Republic. A clinical case from England was identified through the National Center for Biotechnology Information pathogen detection pipeline; the patient did not report contact with leopard geckos. Whole genome sequencing analysis revealed substantial genetic diversity between clinical and animal isolates; however, gecko and clinical isolates from LAC were highly related (1 allele difference). This investigation linking SF illnesses to leopard geckos highlights an important public health risk from pets. A better understanding of how geckos are distributed by the pet industry in the United States could improve traceability to points of origin and mitigate Salmonella transmission at gecko breeders. Earlier NVSL reports of SF isolates from geckos suggest the risk of human SF infection from geckos is not new. This investigation demonstrates a need to educate gecko breeders, retailers and gecko owners about the continued Salmonella infection risk from pet geckos.  相似文献   
7.
Leptin is a potential satiety factor and plays an important role in both metabolism and reproduction; both leptin and its receptor (Ob‐R) have been detected in human spermatozoa, thus suggesting leptin involvement in male gamete physiology. This experiment was designed to investigate leptin receptor [the long isoform (Ob‐Rb)] mRNA in bull ejaculated spermatozoa by RT‐PCR and southern hybridization. Total RNA was isolated from ejaculated spermatozoa and purified by different methods. Although the concentrations of RNA determined by all methods (except SDS/Proteinase K, lowest amount of RNA recovery) were similar, ethidium bromide staining was only detectable in lanes containing the samples isolated by sodium dodecyl sulphate (SDS) and SDS/citric acid extraction which produced higher RNA concentration. Ob‐Rb mRNA was detected in all samples using southern hybridization after RT‐PCR; it was shown only in three of them by RT‐PCR. We may conclude that Ob‐Rb mRNA is present in bull spermatozoa and leptin perhaps exerts physiological effects, as already demonstrated in humans and pigs.  相似文献   
8.
This paper documents the evolution of Environmental Protection Agency (EPA) policy concerning the relative roles that volatile organic compounds (VOCs) and oxides of nitrogen (NOx) emissions play in ozone nonattainment planning for State implementation plans (SIPs). It further discusses possible new control requirements, including NOx measures, that may be required as a result of pending Clean Air Act Amendments. In the early 1970's EPA guidance emphasized the use of VOC control measures to attain the ozone (formerly oxidant) ambient air quality standard. Little if any, control requirements applied to NOx emissions. EPA continued to focus guidance requirements upon the control of VOCs during the planning efforts associated with the 1977 Clean Air Act amendments... 1979 SIPs, 1982 plans for long-term problem areas (extension areas), and other revisions to SIPs. Preliminary air quality modeling work to support these later planning efforts revealed that, in certain cases, there were potential benefits of NOx control in addition to VOC. With this new insight, EPA's post-1987 policy proposal required states to look at the potential benefits of NOx controls in areas with a nonmethane organic compound to NOx ratio of 10∶1 or greater. In Clean Air Act Amendments currently being debated in the House and Senate, there is an uncertainty with regard to the role of NOx controls. Possibilities under consideration range from the application of reasonably available control technology for 100 ton sources of NOx to a clean fuel motor vehicle program within 42 months of enactment.  相似文献   
9.
Conventional tillage practices on steep and fragile landscape of Himalayan hills result in significant loss of topsoil during rainy season. Soil erosion in Nepal mid-hills is the most critical during pre-monsoon season. Many reviews argue that reduced tillage could be an option to tackle this problem. However, very few field experiments to evaluate reduced tillage systems have to date been conducted in this region. Thus, a field experiment was initiated in factorial randomized complete block design on acidic sandy loam soil (Lithic Dystochrept) during the summer season of 2001 at Kathmandu University (1500 masl) to assess the effects of tillage and cropping patterns on soil and nutrient losses, crop yield and soil fertility. Two main treatments viz. conventional and reduced till, and two sub-treatments viz. sole maize (Zea mays) and maize + soybean (Glycine max) were considered. Soil organic carbon (OC), total nitrogen (N), plant available phosphorus (P) and exchangeable potassium (K) were determined for the original soil and eroded sediment using standard methods. Two years of data indicated annual soil and nutrient losses to be significantly lowered by reduced till as compared to conventional till. Total annual soil loss from conventional and reduced till was 16.6 and 11.1 Mg/ha, respectively. Similarly, annual nutrient losses associated with the eroded sediment were 188 kg OC/ha, 18.8 kg N/ha, <1 kg P/ha and 3.8 kg K/ha for conventional till and 126 kg OC/ha, 11.8 kg N/ha, <1 kg P/ha and 2.4 kg K/ha for reduced till. Soil OC and N losses were significantly higher in conventional till and this may be one of the major causes of fertility depletion in the Nepalese hills. Soil chemical properties did not differ due to tillage and cropping systems; however, over years pH, N and P were increased irrespective of treatments. Although treatments were at par for maize grain yield, conventional till + soybean produced highest grain yield (4.0 Mg/ha) followed by reduced till + soybean (3.9 Mg/ha) and conventional till sole maize (3.8 Mg/ha). Mixed cropping of legumes and maize do not help conserve soil and nutrient loss in hills of central Nepal. Thus, reduced till could be a viable option for minimizing soil and nutrient losses without sacrificing economic yields in central hills of Nepal.  相似文献   
10.
Gesunde Pflanzen - Alternate wetting and drying irrigation (AWDI) is a&nbsp;water-conserving strategy in rice fields. An experiment, conducted as a&nbsp;split-split plot design and based on...  相似文献   
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