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101.
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
102.
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
103.
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
104.
Maggs DJ Sykes JE Clarke HE Yoo SH Kass PH Lappin MR Rogers QR Waldron MK Fascetti AJ 《Journal of Feline Medicine and Surgery》2007,9(2):97-108
To determine the effectiveness of dietary lysine supplementation in cats with enzootic upper respiratory disease (URD), 50 cats were fed a ration containing 11 or 51 g lysine/kg diet for 52 days. Food intake, body weight, clinical signs, plasma amino acid concentrations and presence of Chlamydophila felis or feline herpesvirus (FHV)-1 DNA within the conjunctival fornix were assessed. Food and lysine intake of both dietary groups decreased between days 17 and 22, coinciding with peak disease and viral presence. Mean disease score for cats fed the supplemented ration (0.94) was higher than for those fed the basal diet (0.21); however, this could be attributed to a small subset of male cats which demonstrated fighting behavior that may have contributed to stress within that cage. FHV-1 DNA was detected on 12 occasions in six cats receiving the supplemented diet and on one occasion in one cat fed the basal diet. C felis DNA was never detected. Mean plasma arginine concentration was lower and plasma lysine concentration was higher in supplemented cats. Mean plasma arginine concentration declined throughout the study in both dietary groups. Data from the present study raise important questions but do not permit a definitive conclusion regarding the efficacy of dietary lysine supplementation in cats with enzootic URD. 相似文献
105.
Xenotransplantation and the potential risk of xenogeneic transmission of porcine viruses. 总被引:1,自引:0,他引:1
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The clinical success of allotransplantation and the shortage of donor organs have led to a proposal for the use of animal organs as alternative therapeutic materials for humans. In that regard, swine are preferable to non-human primates as a source of donor organs. While applications for clinical trials for xenotransplantation have not yet been received in Canada, several trials have already been authorized in the United States. A major concern, however, is the potential for xenogeneic transmission of viruses from animals to humans via organ, tissue, or cellular transplantation or via ex vivo exposure of humans to porcine biologic materials. Xenotransplantation allows viruses to bypass the normal immunological defense mechanisms of the recipient. Furthermore, the use of immunosuppressive drugs following transplantation may facilitate the xenogeneic transmission of zoonotic agents. Of porcine viruses, swine hepatitis E virus does not cause any clinical symptoms in the natural host but is a likely zoonotic agent that can infect humans and cause hepatitis. Porcine circovirus type 1 is prevalent in swine populations with no known association with clinical disease, while circovirus type 2 causes post-weaning multi-systemic wasting syndrome. Porcine endogenous retrovirus is integrated into the host chromosomes while porcine cytomegalovirus undergoes latent infection. Two additional porcine herpesviruses have recently been identified in swine and have been named porcine lymphotrophic herpesviruses. These herpesviruses can potentially become reactivated in human recipients after xenotransplantation. All in all, there are a number of viruses in swine that are of primary concern to screen and eliminate from xenotransplantation protocols. Epidemiology and the current knowledge on xenogeneic risk of these viruses are discussed. 相似文献
106.
Hwang IK Yoon YS Choi JH Yoo KY Yi SS Chung DW Kim HJ Kim CS DO SG Seong JK Lee IS Won MH 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2008,70(4):373-377
Spontaneously hypertensive rats (SHRs) are widely accepted in medical research because this model has been used for studies in neurodegenerative diseases such as vascular dementia and stroke. In the present study, we observed newly generated neuronal precursors using doublecortin (DCX, a marker of neural proliferation and differentiation) in the subgranular zone of the dentate gyrus in SHRs compared to Sprague-Dawley rats (SDRs) at various age stages. DCX immunoreactivity, immunoreactive cell numbers and its protein level in the dentate gyrus of the SHRs were higher than those in the SDRs at postnatal month 1 (PM 1). At PM 8, DCX immunoreactivity, immunoreactive cell numbers and protein levels in both groups were markedly decreased compared to those at PM 1; however, they were higher than those in the SDRs. They were decreased in the both groups with age: DCX immunoreactive cells in the SDRs were few at PM 12. Our results indicate that newly generated neuronal precursors are more abundant in SHRs than in SDRs during their life. 相似文献
107.
Su In Lee Sang Gyun Kang Mi Lan Kang Han Sang Yoo 《Journal of veterinary diagnostic investigation》2008,20(4):492-496
Fimbriae and enterotoxins are major virulence factors associated with enterotoxigenic Escherichia coli (ETEC). In this study, 3 sets of multiplex polymerase chain reaction (mPCR) assays targeting fimbriae, enterotoxins, and other adherence factors were developed for detecting ETEC. A total number of 188 E. coli field isolates were examined, and percentages of E. coli strains carrying each virulence factors were as follows: F4 (7.45%), F5 (29.79%), F6 (6.38%), F18 (15.43%), F41 (3.72%), STa (10.11%), STb (20.74%), LT (9.57%), Stx2e (2.13%), EAST1 (42.02%), F1 (67.55%), AIDA-I (2.66%), and pAA (7.45%). Of the 188 E. coli field isolates examined, 25.53% were found to be pathogenic ETEC, having both fimbriae and enterotoxins. However, the ratio increased to 44.68% when the presence of other adhesins was considered as criteria for virulence. Among the adherence factors, F1 was found to be the most prevalent. AIDA-I and pAA were also found with similar ratio as compared with other virulence factors. In addition, virulence patterns carrying these alternate adhesive genes with enterotoxins were detected with significant ratio. Therefore, it is desirable that alternate adhesins be considered as markers for diagnosis of ETEC. 相似文献
108.
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
109.
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
110.
Lee JC Hwang IK Park SK Yoo KY Seo K Kang TC Oh YS Won MH 《Anatomia, histologia, embryologia》2005,34(4):252-257
This study was carried out to investigate the motor neurone degeneration in the ventral horn following transient spinal cord ischaemia at normothermic conditions in rabbits. Transient spinal cord ischaemia was induced by occlusion of the abdominal aorta underneath the left renal artery for 15 min at normothermia (38.7 degrees C). Sections at the level of L7 were examined using histochemical and electron microscopic methods. Cresyl violet-positive motor neurones began to reduce in number at 3 h after ischaemia reperfusion, and were not detectable at 48 h after ischaemia reperfusion. Acid fuchsin-positive motor neurones were detected at 1 h after ischaemia reperfusion, significantly increased up to 6 h after the ischaemia reperfusion, and eventually disappeared by 48 h after ischaemia reperfusion. In electron microscopic findings, the disintegration of cytoplasmic membranes, and the disruption of mitochondria and endoplasmic reticulum were observed in motor neurones at 30 min after ischaemia reperfusion. Motor neurones showed necrotic findings with pyknotic degeneration at 1 h after ischaemia reperfusion. The necrotic degeneration became severer time dependently after ischaemia reperfusion. At 48 h after ischaemia reperfusion, cellular components were not detectable in motor neurones. In conclusion, we suggest that the degeneration pattern of motor neurones of the ischaemic spinal cord was necrotic after ischaemia reperfusion under normothermic conditions. 相似文献