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441.
Kawauchi J Zhang C Nobori K Hashimoto Y Adachi MT Noda A Sunamori M Kitajima S 《The Journal of biological chemistry》2002,277(41):39025-39034
442.
We detected a peptide having a behavioral activity on mouse forced swimming from sera of healthy volunteers without affective and psychotic diseases. The amino acid sequence was GVNDNEEGF, which was found in the sequence of human beta-fibrinogen. The synthesized peptide also showed the behavioral activity dose-dependently, but human fibrinopeptide B (QGVDNEEGFFSAR) did not. The activity was decreased by dopamine 1 antagonist SCH-23390, but not by dopamine 2 antagonist sulpiride. These findings strongly suggest that metabolism of human beta-fibrinogen induces the fragment affecting the mouse behavior via the dopamine1 neuronal activity. 相似文献
443.
Matsuur H Asakawa C Kurimoto M Mizutani J 《Bioscience, biotechnology, and biochemistry》2002,66(7):1576-1578
Alpha-glucosidase inhibitory activities were found in aqueous methanol extracts of the seeds of Momordica charantia and the fruit bodies of Grifola frondosa. An active principle against the enzyme prepared from rat small intestine acetone powders was isolated and characterized. The structure of the isolated compound was identified as D-(+)-trehalose by FDMS, 1H-, 13C-NMR, and [alpha]D measurements. The inhibitory activity of trehalose was compared with 1-deoxynojirimycin. Trehalose showed 45% inhibitory activity at the concentration of 2 x 10(-3) m, but 1-deoxynojirimycin had 52% inhibitory activity at 1 x 10(-7) M. 相似文献
444.
445.
The purpose of this study was to investigate the relationship between muscle oxygenation level at exhaustion and maximal oxygen uptake (VO2max) in an incremental cycling exercise. Nine male subjects took part in an incremental exhaustive cycling exercise, and then cuff occlusion was performed. Changes in oxy-(deltaHbO2) and deoxy-(deltaHb) hemoglobin concentrations in the vastus lateralis muscle were measured with a near infrared spectroscopy (NIRS). Muscle oxygenation during incremental exercise was expressed as a percentage (%Moxy) of the maximal range observed during an arterial occlusion as the lower reference point. A systematic decrease was observed in %Moxy with increasing intensity. A significant relationship was observed between %Moxy at exhaustion and VO2max (p < 0.01). We concluded that the one of the limiting factor of VO2max is the muscle oxygen diffusion capacity, and %Moxy during exercise could be one of the indexes of muscle oxygen diffusion capacity. 相似文献
446.
Matsuura H Chiji H Asakawa C Amano M Yoshihara T Mizutani J 《Bioscience, biotechnology, and biochemistry》2003,67(11):2311-2316
1,1-Dipehnyl-2-picrylhydrazyl (DPPH) radical scavenging activities were found in the extract of dried leaves of oregano (Origanum vulgare). The water-soluble active ingredients were isolated, and their structures were determined to be 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate and 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl 4-O-methylprotocatechuate by (1)H-, (13)C-NMR, DEPT, HMQC, and HMBC spectral analyses, and by NOE experiments. The DPPH radical scavenging activities of these compounds were compared with those of rutin, quercetin and rosmarinic acid at a concentration of 2 x 10(-5) M. The scavenging activity of 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate was almost the same as that of quercetin and rosmarinic acid, but that of 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybennzyl 4-O-methylprotocatechuate was less than that of quercetin, rosmarinic acid and 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate. The amount of 4'-O-beta-D-glucopyranosyl-3',4'-dihydroxybenzyl protocatechuate was estimated to be 3.8 mg/1 g of dried leaves by an HPLC analysis. 相似文献
447.
Matsui T Kondo T Nakatani S Omawari N Sakai M Mori H Ogata A Kato J Ohno H Obata T Nakai H Toda M 《Bioorganic & medicinal chemistry》2003,11(18):3937-3943
(1S,2R)-2-Acylamino-1-methyl-2-phenylethyl phosphate derivatives 2a, 2b, 3a, and 5a, which are conformationally restricted and metabolically stable analogues of (2R)-2-acylamino-2-phenylethyl phosphate derivatives 1a and 1b, are a new class of inhibitors of TNF-alpha production. More efficient alternative synthesis of a key intermediate, (1R,2S)-1-amino-1-(3-methoxyphenyl)propan-2-ol hydrochloride (9), was achieved using one-step, three-component coupling of 3-methoxyphenyl boronic acid (13), (5S)-2,2,5-trimethyl-1,3-dioxolan-4-ol (14), and amino diphenyl methane (15), [as reported in J. Am. Chem. Soc. 1998, 120, 11798]. Evaluation of the hypotensive activity of these compounds was done to assess one of their side effects. Among the compounds tested, the above-mentioned four compounds (2a, 2b, 3a, and 5a) were identified as inhibitors with both sufficient potency and an acceptable safety margin regarding their hypotensive activity. The pharmacodynamics of these compounds were also investigated. Single-dose pharmacokinetic data for compounds 2a, 2b, 3a, and 5a are displayed. These compounds were estimated to be mainly metabolized by the liver in the species tested based on their in vitro stability in tissue homogenates and plasma. A representative compound, 2a, showed good linearity of its plasma concentration after intravenous injection. 相似文献
448.
Yamazaki J Katoh H Yamaguchi Y Negishi M 《Biochemical and biophysical research communications》2005,332(3):782-786
The G alpha subunits of the G12 family of heterotrimeric G proteins, G alpha12 and G alpha13, are closely related in sequences and some effectors, but they often act through different pathways or bind to different proteins. We have examined subcellular distribution of these two G proteins and found that endogenous G alpha12 and G alpha13 localize in membrane and cytoplasmic fractions, respectively. Exogenously expressed G alpha12 and G alpha13 also localize in membrane and cytoplasmic fractions, respectively, in COS-7 cells. Stimulation of lysophosphatidic acid receptor coupled to G alpha13 markedly promotes the translocation of G alpha13 from cytoplasm to membrane. This different localization of G alpha12 and G alpha13 may explain some of the nonoverlapping actions of G alpha12 and G alpha13. 相似文献
449.
Wang L Mitoma J Tsuchiya N Narita S Horikawa Y Habuchi T Imai A Ishimura H Ohyama C Fukuda M 《Biochemical and biophysical research communications》2005,331(4):958-963
The expression of core 2 beta1,6-N-acetylglucosaminyltransferase-1 (C2GnT) is associated with development and progression of malignancy. Sequence analysis showed that the codon 152 of C2GnT has a polymorphism having GTT encoding valine or ATT encoding isoleucine. By examining the polymorphism in prostate cancer and benign prostatic hyperplasia patients, we found that the C2GnT G allele was more frequently observed in the prostate cancer group (p=0.015) than the control group. Men with the GG genotype had a 3.60-fold increased risk of prostate cancer, and men with the AG genotype had a 1.58-fold increased risk of prostate cancer compared with those with the AA genotype. The G allele was found to have a gene dosage effect for prostate cancer risk. No such risk was associated for benign prostatic hyperplasia. These results demonstrate that C2GnT A/G polymorphism is associated with the susceptibility to prostate cancer in a Japanese population. 相似文献
450.
Matsui Y Ishikawa J Kamitakahara H Takano T Nakatsubo F 《Carbohydrate research》2005,340(7):1403-1406
6-Amino-6-deoxycellulose (4) was synthesized from cellulose by three reaction steps, namely bromination at C-6, displacement of bromine by azide ion, and reduction of the azide group to amino group, in 67% overall yield. The 13C NMR spectrum of compound 4 supports the expected structure for 6-amino-6-deoxycellulose. The degree of substitution of compound 4 was 0.96. 相似文献