巻号一覧
25 巻, 2 号
選択された号の論文の9件中1～9を表示しています
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KINETIC STUDIES ON THE RECIPROCAL REGULATION BY FRUCTOSE BISPHOSPHATE AND CITRATE OF YEAST ACETYL CoA CARBOXYLASE富田 多嘉子, 長谷川 隆一, 林 栄一1979 年 25 巻 2 号 p. 59-66
発行日: 1979年
公開日: 2009/04/28
ジャーナル フリーNeutral lipids, especially triacylglycerols, accumulated due to myo-inositol deficiency both in the cells of Saccharomyces carlsbergensis (HAYASHI et al. (1976) J. Biol. Chem., 251, 5759-5769) and in the liver of the rat (HAYASHI et al. (1974) Biochim. Biophys. Acta, 360, 134-155). The accumulation of triacylglycerols in the deficient yeast resulted, at least partly, from an enhancement of acetyl CoA carboxylase activity. The activation of the enzyme reflected the fluctuation due to the deficiency in the levels of fructose bisphosphate and citrate (HAYASHI et al. (1978) Biochim. Biophys. Acta, 540, 231-237). Thus, the kinetics of the regulation of acetyl CoA carboxylase by these intermediates was studied. In physiological concentrations fructose bisphosphate sigmoidally activated acetyl CoA carboxylase from yeast with the Hill coefficient of 3, while citrate counteracted the fructose bisphosphate activation in a sigmoidal manner with the Hill coefficient of 2. Fructose bisphosphate markedly increased the apparent Vmax value of acetyl CoA carboxylase for the substrate, ATP and slightly decreased the apparent Km value. Citrate greatly decreased the apparent Vmax value increased by fructose bisphosphate.抄録全体を表示PDF形式でダウンロード (752K) -
足立 昌子, 小林 正1979 年 25 巻 2 号 p. 67-78
発行日: 1979年
公開日: 2009/04/28
ジャーナル フリーIdentification of vitamin D3 and 7-dehydrocholesterol (7-DHC) in cow's milk by gas chromatography-mass spectrometry (GC-MS) and their quantitation by high-performance liquid chromatography (HPLC) were investigated. When vitamin D and provitamin D fractions purified from a sample of commercial cow's milk were applied to GC-MS, the results showed that the fractions contained vitamin D3 and 7-DHC, respectively, while neither vitamin D2 nor ergosterol could be detected in the milk. HPLC methods for the determination of vitamin D3 and 7-DHC in cow's milk were then proposed as routine methods. The method for assaying vitamin D3 included the isolation of lipids from milk according to the directions of BELL and CHRISTIE (5), saponification, isolation of unsaponifiable matter, digitonin-Celite column chromatography, prepara-tive thin-layer chromatography (TLC) and application to HPLC. On the other hand, 7-DHC in milk could be simultaneously determined without the purification by digitonin-Celite column chromatography. The peak corresponding to either vitamin D3 or 7-DHC in the respective HPL-chromatograms was clearly separated from possible interfering substances and the recovery experiments for both vitamin D3 and 7-DHC gave satisfactory results. When the proposed methods were applied to 10 samples of commercial cow's milk, the assayed values of vitamin D3 and 7-DHC were 19-79 I.U./liter and 14-56 μg/liter, respectively.抄録全体を表示PDF形式でダウンロード (1158K) -
下辻 常介, 清野 佳紀, 石田 允, 石井 経康, 池原 千衣子, 日衛島 禎介, 藪内 百治1979 年 25 巻 2 号 p. 79-86
発行日: 1979年
公開日: 2009/04/28
ジャーナル フリーThe plasma levels of 25-hydroxyvitamin D (25-OH-D) were determined in 27 healthy mothers and their infants as well as in the cord blood at the time of delivery, and in another 95 children of different ages. The plasma 25-OH-D levels in the infants, cord blood and mothers at the time of delivery were 11.4±8.6 ng/ml (mean±SD, n=27), 12.8±8.2 ng/ml (mean±SD, n=25) and 16, 3±8.1 ng/ml (mean±SD, n=27), respectively. These values are significantly lower (p<0.01) than the value of 21.6±10.1 ng/ml (mean±SD, n=17) in normal children (1-15 years of age). Significant correlations were found between the plasma 25-OH-D levels of the infants and the mothers, and between those of the mothers and cord bloods, with correlation coefficients of r=0.62 (p<0.01, n=27) and r=0.78 (p<0.01, n=25), respectively.
The plasma 25-OH-D concentration was normally maintained at a low level for 1-2 months after birth and then rose. No significant correlation was found between the plasma 25-OH-D and plasma Ca levels. The above findings suggest that 25-OH-D is transferred from the mother to the infant through the placenta, but that the blood 25-OH-D level is low for a few months after birth, possibly owing to a low rate of 25-hydroxylation of vitamin D during this period.抄録全体を表示PDF形式でダウンロード (640K) -
駒井 三千夫, 木村 修一1979 年 25 巻 2 号 p. 87-94
発行日: 1979年
公開日: 2009/04/28
ジャーナル フリーPrevious data have shown that the life span of small intestine epithelial cells in germ-free (GF) mice was 4.3 days, while that in conventional (CV) mice was 2.1 days, under ad libitum feeding. On the other hand, in the author's laboratory, it was also found that feeding conditions affected the cells' life span. That is, in CV mice the life span of the cells lengthened under restricted feeding (2.6 days), compared with under ad libitum feeding (1.8 days).
In the present experiment the life span of small intestine epithelial cells was investigated using radioautography, under controlled feeding (setting it equal to ad libitum feeding) and restricted feeding, in both CV and GF mice. Small intestine samples were taken from the middle part of duodenum, jejunum and ileum. Body weight changes, organ wet weights and intestine were also measured.
In the lower part of the small intestine the effects of a restricted diet on epithelial cell life span prolongation appeared clearly in CV mice, but this effect was reduced in GF mice. This may be partly because the restricted group had slightly shorter villi in the case of GF mice.抄録全体を表示PDF形式でダウンロード (790K) -
土井 裕司, 川口 昇, 伊吹 文男, 金森 正雄1979 年 25 巻 2 号 p. 95-102
発行日: 1979年
公開日: 2009/04/28
ジャーナル フリーBovine κ-casein reduced with 2-mercaptoethanol was fractionated on a DEAE-cellulose column to one nonadsorbed, five major adsorbed and two minor adsorbed fractions. The properties of the nonadsorbed and five major adsorbed fractions were reported in our previous paper (4). In this paper, the characteristics of two minor adsorbed fractions (P-X and P-Y) were reported. Gel electrophoretic patterns of these fractions were similar to κ-casein. These fractions had the same amino acid composition and the same phosphorus content as the major components. P-X contained one residue each of N-acetylneuraminic acid, galactose and galactosamine, and P-Y two residues each. Furthermore, these fractions showed the stabilizing ability for αs1-casein in the presence of calcium ion. These results indicate that P-X and P-Y are minor components of reduced bovine κ-casein.抄録全体を表示PDF形式でダウンロード (1190K) -
不破 英次, David V. GLOVER, 杉本 温美1979 年 25 巻 2 号 p. 103-114
発行日: 1979年
公開日: 2009/04/28
ジャーナル フリーStarch granules were prepared from 14 double- and 26 triple-mutants containing amylose-extender (ae), 14 double- and 18 triple-mutants containing waxy (wx), 15 double- and 20 triple-mutants containing sugary-1 (su1), 13 double- and 23 triple-mutants containing sugary-2 (su2), and 14 double- and 19 triple-mutants containing dull (du) of maize inbred Oh43 (Zea mat's L.). The relative susceptibilities of these starch granules to fungal glucoamylase were determined and the starch granules were examined by scanning electron microscopy. A commercial normal maize starch was used as a control. Starch granules of the double-and triple-mutants containing su1 and su2 were digested two to eight times faster than normal. The ae gene reduced susceptibility and seems to be epistatic to su1 and su2. Starch granules of the double- and triple-mutants containing wx were digested about two times faster than normal and those containing shrunken-2 (sh2) were digested 1.2 to eight times faster than normal. Starch granules of triple-mutant combinations with opaque-2 (O2) showed digestion properties which were comparable to those of their respective nonopaque double-mutant counterpart.抄録全体を表示PDF形式でダウンロード (1528K) -
渡辺 光夫, 高橋 徹三, 吉田 美枝子, 鈴木 正敏, 村松 成司1979 年 25 巻 2 号 p. 115-122
発行日: 1979年
公開日: 2009/04/28
ジャーナル フリーSome metabolites of tryptophan such as 3-hydroxyanthra-nilic acid (3-OHAA), 3-hydroxykynurenine (3-OHKY) and xanthurenic acid (XA) have been suspected of being carcinogenic, and the relationship between bladder cancer and the urinary excretion of these metabolites has been discussed. However, the relationship between the intake of tryptophan and the excretion of these metabolites has not yet been reported. In this work, the urinary excretion of 3-OHAA, 3-OHKY, XA and kynurenic acid (KA) was determined when an experimental diet containing 770 or 850mg/day of tryptophan was given to six normal female human subjects and when 900mg/day of tryptophan was added to the experimental diet. Under the experimental diet, 3-OHAA, 3-OHKY, XA and KA in urine (μmole/day) were 3.57±1.35, 1.95±1.11, 10.11±3.25 and 15.80±2.35, respectively. Under the additional intake of tryptophan, the values increased to 7.07±5.31, 3.90±2.44, 18.85±7.20 and 31.51±7.52, respectively. The averages of excretion were proportional to the tryptophan intake. Mean excretion ratios (%) of 3-OHAA, 3-OHKY, XA and KA Cumoles) to tryptophan intake (μumoles) were 0.086±0.056, 0.053±0.032, 0.245±0.085 and 0.390±0.084, respectively. However, individual differences and daily fluctuations were observed and it was especially remarkable in 3-OHAA in the period of additional tryptophan intake.抄録全体を表示PDF形式でダウンロード (740K) -
松澤 健夫1979 年 25 巻 2 号 p. 123-126
発行日: 1979年
公開日: 2009/04/28
ジャーナル フリーPDF形式でダウンロード (349K) -
八木 國夫, 大石 誠子1979 年 25 巻 2 号 p. 127-130
発行日: 1979年
公開日: 2009/04/28
ジャーナル フリーPDF形式でダウンロード (345K)
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