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131.
5'-Uridylic acid (UMP), which is present at high concentrations in cow's colostrum, has been shown to cause a reduction in increased plasma levels of insulin and glucose after ingestion of milk replacer in pre-weaning calves. However, the precise mechanisms of UMP action have not been investigated, and its action has not been investigated in other pre-weaning ruminants. In order to demonstrate whether UMP causes changes in postprandial metabolic and hormonal parameters in pre-weaning goats, 11 Saanen kids were given milk replacer (twice a day) without ( n  = 5) or with ( n  = 6) UMP (1 g for each meal, 2 g/day for each head) for 14 days. Analysis of blood samples taken in the morning of day 14 demonstrated that the feeding of milk replacer with UMP abolished the significant changes in postprandial plasma glucose, NEFA, GH and insulin concentrations induced by feeding of milk replacer alone, and demonstrated a tendency to increase IGF-I levels. However, there was no significant difference between the two groups at any sampling time. We conclude that UMP feeding with milk replacer showed a tendency to blunt the postprandial changes in levels of some plasma metabolites and hormones that are induced by replacer alone in pre-weaning goats.  相似文献   
132.
Twenty‐eight original chicken microsatellite markers were isolated and characterized to determine their utility as cross‐reactive markers for comparative genetic mapping in the order Galliformes. Primer pairs were typed in 12 unrelated chickens and also tested on Japanese quail and helmeted guinea fowl deoxyribonucleic acid (DNA). Polymorphism was observed in 23 (82.1%) of the markers and the average number of alleles per locus was 2.9 while the mean heterozygosity was 0.19. Eleven (39.3%) of the chicken markers cross‐reacted with Japanese quail DNA and 2 (7.1%) with helmeted guinea fowl DNA. The cross‐reactive markers described would serve as useful resources for comparative genetic mapping in poultry species belonging to the order Galliformes.  相似文献   
133.
Artepillin C (AC), an active ingredient of Brazilian propolis, permeates intact across Caco-2 cells by transcellular passive diffusion. The permeation of AC across Caco-2 cells is as efficient as that of phenolic acids and the microbial metabolites of poorly absorbed polyphenols, which are actively absorbed by the monocarboxylic acid transporter (MCT) (Biochim. Biophys. Acta 2005, 1713, 138-144). Here, the absorption of orally administered AC in rats has been studied to evaluate its pharmacokinetics and bioavailability in vivo in comparison with those of p-coumaric acid (CA), a substrate of MCT. Rats were given 100 micromol/kg of body weight of AC or CA, and blood was subsequently collected from the portal vein and abdominal artery. AC, CA, and their metabolites were quantified by coulometric detection using HPLC-ECD. The serum concentration of intact AC and CA in the portal vein peaked at 5-10 min after administration, with a C(max) of 19.7 micromol/L for AC and 74.8 micromol/L for CA. The area under the curve (AUC) for intact AC and CA in the portal vein was calculated from the serum concentration as 182.6 and 3057.3 micromol.min.L(-1), respectively. The absorption efficiency of CA was about 17-fold higher than that of AC. Furthermore, the bioavailability of CA was about 278-fold higher than that of AC, and the ratio of AUC in the abdominal artery to AUC in the portal vein was 0.04 and 0.70, for AC and CA, respectively. Thus, AC is likely to be more susceptible to hepatic elimination than is CA. The bioactive compound of AC in vivo should be investigated further.  相似文献   
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p-Coumaric and ferulic acid are actively taken up by monocarboxylic acid transporter (MCT), whereas gallic acid, caffeic acid (CA), and rosmarinic acid (RA) are absorbed by paracellular diffusion in human intestinal Caco-2 cells, although CA has low affinity for MCT. We previously demonstrated that p-coumaric acid has a much higher absorption efficiency than gallic acid in rats, owing to the MCT-mediated absorption of p-coumaric acid in vivo (J. Agric. Food Chem. 2004, 52, 2527-2532). Here, absorption of orally administered CA and RA in rats has been studied to investigate their intestinal absorption characteristics and pharmacokinetics in vivo and to compare the results with those of p-coumaric and gallic acids obtained under identical conditions. Rats were given 100 micromol/kg body weight of CA and RA, and blood was collected from the portal vein and abdominal artery after administration. CA, RA, and their metabolites were quantified by a coulometric detection method using HPLC-ECD. The serum concentration of intact CA and RA in the portal vein peaked at 10 min after administration, with a C(max) of 11.24 micromol/L for CA and 1.36 micromol/L for RA. The area under the curve (AUC) for intact CA and RA in the portal vein was calculated from the serum concentration-time profile to be 585.0 and 60.4 micromol min L-1, respectively. The absorption efficiency of CA was about 9.7-fold higher than that of RA. Overall, the absorption efficiency of these compounds in vivo increases in the order: gallic acid = RA < CA < p-coumaric acid, which is in good agreement with results obtained in Caco-2 cells in vitro.  相似文献   
138.
A study was conducted to investigate whether ovulation in gilts could be synchronized for embryo collection by the administration of estradiol benzoate (EB) or estradiol dipropionate (EDP) to induce pseudopregnancy, followed by the treatment with prostaglandin F (PGF) on 10 days after. Ten gilts each received a total of 20 mg of EB or EDP on Day 10 or EB on Day 10 and 14 to induce pseudopregnancy (Day 0 = onset of estrus). Donors received PGF 10 or 15 days (as a control) after the first administration of estrogens and subsequently eCG and hCG, and were then inseminated artificially. The embryos were collected 7 days after the administration of hCG, and assessed for embryo yield and their developmental stages. All protocols resulted in good embryo yield (9.8–13.2 embryos in average), and the embryos showed average ability to develop to the expanded blastocyst stage (3.29–4.03 as developmental scores) without any significant differences among the protocols. These results suggest that the administration of PGF 10 days after the treatment of gilts with EB or EDP would allow synchronization of ovulation and embryo collection, as well as shortening the period from estrus detection to embryo collection, thus improving embryo collection efficiency.  相似文献   
139.
Wasting marmoset syndrome (WMS) is a serious disease in captive common marmoset (Callithrix jacchus) colonies. Because of the high mortality rates, elucidation of the underlying mechanisms is essential. In this study, we compared the histopathology, the number of each epithelial cell in the jejunum and colon, and the expression patterns of some molecular markers between healthy and WMS-affected marmosets. Atrophy of villi in the jejunum and mononuclear cell infiltration in the lamina propria were observed in the intestinal tract of WMS-affected marmosets. Although the numbers of transient amplifying cells and tuft cells were increased, the number of goblet cells was obviously decreased in the jejunum and colon of WMS-affected marmosets compared to healthy marmosets. In addition, the number of enterocytes in the jejunum was decreased in WMS animals. There was no apparent difference in the numbers of stem cells, enteroendocrine cells, or Paneth cells. The expression of β-catenin and Tcf7l2 was increased in WMS, and the co-existence of β-catenin and Tcf7l2/Cyclin D1 was observed around the crypts in WMS-affected marmosets. These findings suggest that cell proliferation continues, but cell differentiation is halted in the intestinal tract due to the enhanced β-catenin/Tcf7l2/Cyclin D1signaling pathway in WMS, which results in malfunction of the villus and mucosa.  相似文献   
140.
ABSTRACT: Heating temperatures of 30–40°C and KCl concentrations of 0.1–0.5 M altered the denaturation mode of carp myofibrils. In 0.1 M KCl medium, heating temperature affected the denaturation of rod more significantly than of subfragment-1 (S-1), and a slow decrease in solubility at 30°C was accompanied by a slow denaturation of rod. KCl concentration at heating altered the denaturation mode differently at 30°C and 40°C. Increased KCl concentrations for heating reduced the rod denaturation rate at 40°C, but it was increased at 30°C. At concentrations above 0.3*Τ*M KCl, the denaturation rate for rod became identical to that for S-1 at both temperatures. Upon heating of chymotryptic digest of myofibrils, S-1 denaturation was similarly detected as in intact myofibrils, whereas practically no rod denaturation was detected. Thus, it was concluded that myosin structure connecting S-1 and rod has an important role in the denaturation process.  相似文献   
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