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101.
Surveillance and diagnosis of avian metapneumovirus (AMPV) infection typically involve measurement of serum antibodies. In the current study, eggs instead of serum samples were used for the detection of AMPV antibodies in egg-laying chicken hens by enzyme-linked immunosorbent assay (ELISA). AMPV-free commercial layer hens were experimentally challenged with AMPV strain SC1509 through intravenous or oculonasal administration. Antibody levels were determined by ELISA. AMPV antibodies were detected in egg yolks from challenged hens by 7 days postinoculation (dpi), with the peak titer at 16 dpi. Antibody levels in eggs laid at 28 dpi correlated well (r = 0.93) with sera taken 28 dpi from the same hens. In a field trial of the yolk ELISA, six broiler breeder farms were surveyed, and all tested positive for AMPV antibodies in hen eggs, although positivity varied from farm to farm. Abnormal discolored eggs collected from outbreak farms had significantly higher titers of AMPV yolk antibodies than normal eggs from the same farm, unlike clinically healthy farms, where normal and abnormal eggs had similar antibody titers. These results indicate that diagnosis of AMPV infection by yolk ELISA to detect anti-AMPV antibodies may be a suitable alternative to serologic testing. 相似文献
102.
Kim HJ Kim ET Lim CY Park C Kang BT Kim JW Yoo JH Park HM 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(8):869-872
IgG immunoreactivity to Malassezia pachydermatis was compared in atopic and non-atopic dogs. Malassezia pachydermatis proteins with a molecular weight of 98 kDa were recognized at a significantly higher frequency in the sera of atopic dogs. Most of the atopic dogs with Malassezia dermatitis had a greater IgG response than did normal dogs. 相似文献
103.
Park C Yoo JH Kim HJ Kang BT Park HM 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(11):1265-1268
Three 7-week-old, English cocker spaniel littermates were diagnosed as having juvenile cellulitis with concurrent neurologic signs based on history, histopathology, and therapeutic response. The puppies were treated with cyclosporin A and prednisolone. Skin lesions and hindlimb paresis improved following treatment. 相似文献
104.
The effects of scoparone on dopamine release in PC12 cells were investigated. Scoparone at 50–200 µM increased dopamine release into the culture medium. However, the released levels of dopamine by scoparone were not altered in the absence of extracellular Ca2+ and by adenylyl cyclase inhibitor MDL-12,330A. Scoparone increased phosphorylation of PKA, CaMK II and synapsin I. Scoparone also enhanced K+-induced levels of dopamine release by CaMK II phosphorylation. These results suggest that scoparone increases dopamine release by synapsin I phosphorylation via activation of PKA and CaMK II, which are mediated by cyclic AMP levels and Ca2+ influx. 相似文献
105.
Improvement of the ventilation system of a naturally ventilated broiler house in the cold season using computational simulations 总被引:3,自引:0,他引:3
106.
Kim JM Kim JS Yoo H Choung MG Sung MK 《Journal of agricultural and food chemistry》2008,56(18):8427-8433
Anti-inflammatory and antiproliferative activities of anthocyanidins and anthocyanin-rich black soybean seed coats were studied in HT-29 human colon adenocarcinoma cells and carcinogen-treated F344 rats, respectively. Cyanidin and delphinidin significantly inhibited cell growth at concentrations of >or=1 microM. Anthocyanidins suppressed cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) mRNAs in TPA-stimulated HT-29 cells. Both yellow and black soybean seed coat supplementation (10%, w/w) did not significantly reduce the number of aberrant crypt foci (ACF), although a modest decrease in the number of ACF was observed in animals fed soybean seed coats. The colonic COX-2 mRNA level was suppressed in rats fed both soybean seed coat diet. The plasma prostaglandin E 2 (PGE 2) level was reduced only in rats fed black soybean seed coats. No difference was observed in either colonic iNOS mRNA or plasma nitric oxide level. These results indicate that anthocyanidins are possible anti-inflammatory agents; however, further studies are required to determine required intake levels in vivo to exert antitumor effect. 相似文献
107.
Park HR Yoo MY Seo JH Kim IS Kim NY Kang JY Cui L Lee CS Lee CH Lee HS 《Journal of agricultural and food chemistry》2008,56(22):10493-10497
Inhibition of acyl CoA:diacylglycerol acyltransferase (DGAT), which is a key enzyme in triglyceride synthesis in eukaryotic organisms, has been proposed as one of the drug targets for treating obesity, type II diabetes mellitus, and metabolic syndrome. Bioassay-guided fractionation of EtOH extract of the flower buds of Tussilago farfara , using an in vitro DGAT enzyme assay, resulted in the isolation of four known sesquiterpenoids, tussilagonone (1), tussilagone (2), 7beta-(3-ethyl-cis-crotonoyloxy)-1alpha-(2-methylbutyryloxy)-3,14-dehydro-Z-notonipetranone (3), and 8-angeloylxy-3,4-epoxy-bisabola-7(14),10-dien-2-one (4). DGAT1 inhibitory activity was studied by in vitro DGAT assay using rat liver microsomes and HepG2 cell microsomes. They showed DGAT1 inhibition with IC(50) values of 99.2 (1), 18.8 (2), 47.0 (3), and 211.1 (4) microM (for rat liver microsomes) and >1 mM (1), 49.1 (2), 160.7 (3), and 294.4 (4) microM (for HepG2 cell microsomes), respectively. Compound 2 showed the most potent inhibition against microsomal DGAT1 derived from rat liver and human hepatocellular carcinoma HepG2 cells and also significantly inhibited triglyceride synthesis by suppressing incorporation of [(14)C]acetate or [(14)C]glycerol into triglycerides in HepG2 cells. These findings suggest that tussilagone is a potential lead compound in the treatment of obesity and type 2 diabetes. 相似文献
108.
Okorie E. Okorie Su Hong Ko Sugeun Go Jun‐Young Bae Gwang Yeol Yoo Jun‐Ho Lee Tae‐Ik Kim Sungchul C. Bai 《Journal of the World Aquaculture Society》2011,42(5):657-666
A 14‐wk feeding trial was carried out to evaluate the optimum dietary riboflavin (vitamin B2) level in juvenile sea cucumber, Apostichopus japonicus. A total of 360 sea cucumbers averaging 1.49 ± 0.07 g (mean ± SD) were randomly distributed into 18 rectangular plastic tanks, and each tank was then randomly assigned to one of three replicates of six diets containing 0.29 (B20), 4.22 (B24), 8.93 (B29), 17.9 (B218), 56.7 (B257), and 577 (B2577) mg riboflavin/kg diet. At the end of 14 wk of feeding trial, average weight gain (WG) of sea cucumbers fed B29, B218, B257, and B2577 diets were significantly (P < 0.05) higher than that of animals fed B20 diet. WG of sea cucumbers fed B218, B257, and B2577 diets were significantly higher than those of animals fed B20 and B24 diets. Specific growth rate of sea cucumbers fed B29, B218, B257, and B2577 diets were significantly higher than those of animals fed B20 and B24 diets. Feed efficiency of sea cucumbers fed B29, B257, and B2577 diets were significantly higher than those of animals fed B20 and B24 diets. Although significant differences were recorded in proximate composition of sea cucumbers fed the experimental diets, no clear trends were observed. The ANOVA test suggested that the optimum dietary riboflavin level in sea cucumber could be 17.9 mg/kg diet but broken‐line analysis of WG indicated a level of 9.73 mg riboflavin/kg diet. Therefore, these results may indicate that the optimum dietary riboflavin level in sea cucumber could be higher than 9.73 mg/kg diet but lower than 17.9 mg/kg diet. 相似文献
109.
1. Shedding of group-specific antigen of avian leukosis virus (ALV) into egg albumen was determined in three Australorp lines: AS line that had been selected primarily for short oviposition interval, ASS line that had been derived from the AS line and developed as a commercial dam line for egg laying, and AC line that had been kept as a randombred control. 2. The proportion of shedders was 13.1 to 16.7% in the AS line in 1984-88, 16.3% in the ASS line in 1984 (before culling of the shedders), and 6.1% and 6.6% in the AC line in 1984 and 1988, respectively. 3. In the AS line, shedders were 1.8% lower in rate of lay to 300 d of age, 1.3 g lower in average egg weight at 34 weeks of age, 5.6% lower in hatchability of fertile eggs and 0.24 h shorter in oviposition interval than non-shedders. In the ASS line (1984 only), the differences between shedders and non-shedders were in the same direction, but in magnitude greater for rate of lay and smaller for oviposition interval. 4. The shedders were favoured by the artificial selection because of their shorter oviposition interval and this appeared to be responsible for the higher levels of ALV shedding in the selection lines. 相似文献
110.
Association of the major histocompatibility complex with avian leukosis virus infection in chickens.
1. Association of the B blood group, the major histocompatibility complex (MHC) in chickens, with avian leukosis virus (ALV) infection shown by shedding of group-specific (gs) antigen was studied in an Australorp line selected for short oviposition interval to improve egg production. Three haplotypes (B8a, B9a and B21) were segregating in this line at frequencies of 66.7, 15.6 and 17.8%, respectively, averaged over three generations. 2. The relative risk (odds ratio) of a hen becoming a gs-antigen shedder was calculated for progenies of the dams shedding gs-antigen and those of non-shedding dams separately and pooled over three generations. In the progenies of shedding dams, the relative risk was not significantly different from 1.0 for the three haplotypes. In contrast, in the progenies of non-shedding dams, the relative risk was 0.67, 0.48 and 2.53 for B8a, B9a and B21, respectively, with the last two ratios being significantly different from 1.0. 3. The average effect of haplotype substitution on probability of shedding was estimated from a linear logistic model. The estimates (relative to zero for B8a) for B9a and B21, respectively, were -0.26 and 0.03 among the progenies of shedding dams, and -0.16 and 0.87 among the progenies of non-shedding dams. The last estimate only was highly significant. 4. These results suggest that the three haplotypes were similar in susceptibility to congenital infection through hatching eggs, but differed in susceptibility to post-hatching infection from other infected birds. 相似文献