排序方式： 共有42条查询结果，搜索用时 62 毫秒
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D. Nagaoka Y. Mitsuhashi R. Angell K. E. Bigley J. E. Bauer 《Journal of animal physiology and animal nutrition》2010,94(3):287-292
For the purpose of investigating the mechanism of obesity‐induction/re‐induction including weight‐cycling in beagles, a study was conducted using commercially available dog food combined with human food to mimic at home‐snacking and diet‐supplementation behaviours. Adult female beagles, which had free access to water and exercise, were used (n = 9). All dogs were initially offered two times their daily calculated number of calories using a dry extruded diet plus blend of canola and soybean oils and allowed to eat ad libitum. After 3 weeks, Pecan shortbread cookies were added to the diet mixture. Obesity was induced during a 19‐week period with 1875–2250 kcal/day consumed, on average, during this period. The dogs were then subjected to a weight‐loss regimen while consuming 490–730 kcal/day. After weight loss, a similar degree of obesity was re‐induced for 17 weeks even though dogs consumed only 1125–1250 kcal/day. Body weight, body condition scores, kcal consumption and food efficiency were recorded. Results indicated that less time and fewer kcal were required to re‐induce the same degree of obesity compared with the initial obesity induction. Human snack foods appeared to stimulate appetite and thus contribute to the obese state. Food efficiency was also increased during the obesity‐reinduction period compared with the induction period. This information may help pet owners better understand the need to limit table scraps and human‐type food snacks in dogs prone to obesity as well as weight maintenance after weight loss. 相似文献
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Mitani S Ouchi A Watanabe E Kanesaki Y Nagaoka S Mukai K 《Journal of agricultural and food chemistry》2008,56(12):4406-4417
Kinetic study of the aroxyl radical-scavenging action of catechins (epicatechin (EC), epicatechin gallate (ECG), epigallocatechin (EGC), and epigallocatechin gallate (EGCG)) and related compounds (methyl gallate (MG), 4-methylcatechol (MC), and 5-methoxyresorcinol (MR)) has been performed. The second-order rate constant ( k s) for the reaction of these antioxidants with aroxyl radical has been measured in ethanol and aqueous Triton X-100 micellar solution (5.0 wt %). The k s values decreased in the order of EGCG > EGC > MC > ECG > EC > MG > MR in ethanol, indicating that the reactivity of the OH groups in catechins decreased in the order of pyrogallol B-ring > catechol B-ring > gallate G-ring > resorcinol A-ring. The structure-activity relationship in the free radical-scavenging reaction by catechins has been clarified by the detailed analyses of the pH dependence of k s values. From the results, the p K a values have been determined for catechins. The monoanion form at catechol B- and resorcinol A-rings and dianion form at pyrogallol B- and gallate G-rings show the highest activity for free radical scavenging. It was found that the free radical-scavenging activities of catechins are 3.2-13 times larger than that of vitamin C at pH 7.0. 相似文献
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K Mukai A Ouchi S Takahashi K Aizawa T Inakuma J Terao S Nagaoka 《Journal of agricultural and food chemistry》2012,60(32):7905-7916
Measurements of the singlet oxygen ((1)O(2)) quenching rates (k(Q) (S)) and the relative singlet oxygen absortpion capacity (SOAC) values were performed for 16 phenolic antioxidants (tocopherol derivatives, ubiquinol-10, caffeic acids, and catechins) and vitamin C in ethanol/chloroform/D(2)O (50:50:1, v/v/v) solution at 35 °C. It has been clarified that the SOAC method is useful to evaluate the (1)O(2)-quenching activity of lipophilic and hydrophilic antioxidants having 5 orders of magnitude different rate constants from 1.38 × 10(10) M(-1) s(-1) for lycopene to 2.71 × 10(5) for ferulic acid. The logarithms of the k(Q) (S) and the SOAC values for phenolic antioxidants were found to correlate well with their peak oxidation potentials (E(p)); the antioxidants that have smaller E(p) values show higher reactivities. In previous works, measurements of the k(Q) (S) values for many phenolic antioxidants were performed in ethanol. Consequently, measurements of the k(Q) (S) and relative SOAC values were performed for eight carotenoids in ethanol to investigate the effect of solvent on the (1)O(2)-quenching rate. The k(Q) (S) values for phenolic antioxidants and carotenoids in ethanol were found to correlate linearly with the k(Q) (S) values in ethanol/chloroform/D(2)O solution with a gradient of 1.79, except for two catechins. As the relative rate constants (k(Q)(AO) (S)/k(Q)(α-Toc) (S)) of antioxidants (AO) are equal to the relative SOAC values, the SOAC values do not depend on the kinds of solvent used, if α-tocopherol is used as a standard compound. In fact, the SOAC values obtained for carotenoids in mixed solvent agreed well with the corresponding ones in ethanol. 相似文献
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Begum NA Kinoshita K Kakazu N Muramatsu M Nagaoka H Shinkura R Biniszkiewicz D Boyer LA Jaenisch R Honjo T 《Science (New York, N.Y.)》2004,305(5687):1160-1163
Activation-induced cytidine deaminase (AID) is required for the DNA cleavage step in immunoglobulin class switch recombination (CSR). AID is proposed to deaminate cytosine to generate uracil (U) in either mRNA or DNA. In the second instance, DNA cleavage depends on uracil DNA glycosylase (UNG) for removal of U. Using phosphorylated histone gamma-H2AX focus formation as a marker of DNA cleavage, we found that the UNG inhibitor Ugi did not inhibit DNA cleavage in immunoglobulin heavy chain (IgH) locus during CSR, even though Ugi blocked UNG binding to DNA and strongly inhibited CSR. Strikingly, UNG mutants that had lost the capability of removing U rescued CSR in UNG-/- B cells. These results indicate that UNG is involved in the repair step of CSR yet by an unknown mechanism. The dispensability of U removal in the DNA cleavage step of CSR requires a reconsideration of the model of DNA deamination by AID. 相似文献
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Charles I. Sagoe Tadao Ando Kenji Kouno Toshinori Nagaoka 《Soil Science and Plant Nutrition》2013,59(4):627-634
The effects of the application of organic acid-treated phosphate rocks on the growth and nutrient uptake of Italian rye grass (Lolium multiflorum Lam. cv. Tachiwase) and some properties of the soil were evaluated in a greenhouse pot experiment. Phosphate rocks (PRs) collected from six countries; China, Florida (USA), Jordan, Sri Lanka, Togo, and Tanzania, were treated with 1 M oxalic or tartaric acid at the ratio of 2.5 mL g-1 PR. The organic acid-treated PRs, containing 12–31% water soluble P, were applied to a granitic regosol (pH 5.8) at 200 mg P pot-1 (4 kg soil). Untreated PRs and single superphosphate (SSP) were included in the treatments. Italian ryegrass was grown for 175 dafter planting (DAP) with ample supply of other nutrients and water. Shoots were harvested at 56, 119, and 175 DAP and the soils were analyzed for pH and Olsen-P after the experiment. Application of organic acid-treated PRs consistently increased the dry matter yield and P uptake of the plants compared with the application of untreated PRs at each harvest, but they were less effective than SSP. A larger amount of P (calculated per unit water-soluble P applied) was recovered from the organic acid-treated PRs than from SSP. The amount of residual extractable P in the soils with the organic acid-treated PRs was about the same as or significantly larger than that in the soil treated with SSP. Soil pH was also significantly higher than in the control and SSP soils. The results suggest that organic acids could be used to improve the P availability of PRs to plants with favorable residual effects in terms of available P and soil pH, without exerting any adverse effects on plant growth or nutrient acquisition. 相似文献
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E Ogawa A Nagaoka H Fujise R Takahashi 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1989,51(6):1185-1192
Methemoglobin formation and reduction in canine erythrocytes with inherited high Na,K-ATPase activity (HK cells) were compared with those in normal canine cells (LK cells). Nitrite-induced methemoglobin formation in hemoglobin solutions indicated that the hemoglobin from HK cells was oxidized at essentially the same rate as that of LK cells. However, methemoglobin formation in HK cells was slower due to the inhibition by high glutathione (GSH) concentration. Methemoglobin reduction was allowed to take place on nitrite-treated and washed erythrocytes in a glucose medium and was reduced more rapidly in HK cells than in LK cells. During the reduction, the amounts of lactate and pyruvate increased more rapidly in HK cells, indicating enhanced glycolysis in HK cells. It is thus evident that the hemoglobin of HK cells is more securely protected from nitrite-induced oxidation by the GSH presence in great excess and by the increase in glycolysis. 相似文献
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Kentaro Nagaoka Haolin Zhang Masahiro Arakuni Kazuyoshi Taya Gen Watanabe 《Animal Science Journal》2014,85(12):976-980
In the mouse, L‐amino acid oxidase (LAO) produces hydrogen peroxide by utilizing free amino acids and is a proven antibacterial factor in mammary glands. Mastitis, a bacterial infection of the mammary gland, is the most frequent disease in dairy cattle. Here, we investigate whether LAO is expressed in the mammary gland of dairy cattle and is antibacterial. In dairy cattle, the expression level of LAO mRNA in the mammary gland was considerably lower than that in mice, and LAO activity was not observed in cattle milk that produced hydrogen peroxide. The expression of LAO mRNA was also low in Japanese Black cattle, the same as in Holstein cattle. A higher LAO mRNA expression was observed in the mastitis glands than in the lactating glands. Furthermore, spleen and lymph nodes expressed high levels of LAO mRNA in dairy cattle. We conclude that mammary glands in dairy cattle have lower ability to express the LAO gene compared to that in mice, which may result in a high incidence of mastitis. 相似文献