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991.
The X-ray crystal structure of 1L-1-O-acetyl-2,3:5,6-di-O-isopropylidene-chiro-inositol is described. The inositol ring deviates considerably from the ideal chair conformation to a flattened chair. A comparison of its conformation in solution with that in solid was made by the use of 1H NMR. This conformational analysis revealed that the title compound adopts similar conformations in solid state and in solution states irrespective of solvent polarity. 相似文献
992.
Kariya Y Mulloy B Imai K Tominaga A Kaneko T Asari A Suzuki K Masuda H Kyogashima M Ishii T 《Carbohydrate research》2004,339(7):1339-1346
Two types of fucan sulfate were isolated from chloroform/methanol extract of the body wall of the sea cucumber Stichopus japonicus. One type (type A) contained 3.41 mmol fucose/g and 2.35 mmol sulfate/g, and the molecular mass was determined to be 9 kDa by gel permeation chromatography (GPC). Structural analysis suggested that type A consists of a backbone of (1-->3)-linked fucosyl residues that are substituted at C-4 with fucosyl residues, and that fucosyl residues are sulfated at C-2 and/or C-4. Another type (type B) contained 3.90 mmol fucose/g and 3.07 mmol sulfate/g, and the molecular mass was determined to be 32kDa by GPC. Structural analysis showed that type B is largely composed of unbranched (1-->3)-linked fucosyl residues, and that sulfate substitution(s) occur at C-2 and/or C-4. The potential of both types to inhibit osteoclastogenesis was examined by an in vitro assay system, showing that both types of fucan sulfate inhibit osteoclastogenesis more than 95% at 50 microg/mL concentration. These results suggest that types A and B fucan sulfate from sea cucumber are potent inhibitors of osteoclastogenesis. 相似文献
993.
The X-ray crystal structure of 1d-1,4-di-O-[(S)-O-acetylmandeloyl]-2,3:5,6-di-O-isopropylidene-myo-inositol is described. Both inositol ring and OAM (O-acetylmandeloyl) moiety deviate from their respective ideal conformations. Inositol ring adopts a flattened chair conformation while OAM adopts an ap (antiperiplanar) conformation. A comparison of its conformation in solution with that in solid was made by the use of NOESY and anisotropic shielding effect in (1)H NMR. This conformational study revealed that the title compound adopts similar conformations in both the states. 相似文献
994.
The X-ray crystal structure of 1l-1,2:4,5-di-O-isopropylidene-allo-inositol, is described. The inositol ring deviate slightly from the ideal chair conformation to a flattened chair. A comparison of its conformation in solution with that in solid was made by the use of 1H NMR. This conformational analysis revealed that the title compound adopts similar conformations in solid state and in solution in low polar solvents like benzene and CHCl3 while in high polar solvents such as Me2SO, the solid state conformation is not retained. 相似文献
995.
Ishida H Hata Y Kawato A Abe Y Kashiwagi Y 《Bioscience, biotechnology, and biochemistry》2004,68(9):1849-1857
A novel protein overexpression system of Aspergillus oryzae was constructed. Five promoters which originate from A. oryzae expressed sequence tag (EST) clones in submerged culture were obtained by genome walking. These were subjected to beta-glucuronidase (GUS) reporter assays. The promoter of manganese superoxide dismutase-encoding gene (sodM) showed the most GUS production. The sodM gene was abundantly expressed in submerged culture but little expressed in solid-state culture. The sodM promoter was approximately 3-fold induced by the addition of 0.01% H2O2. Glucoamylase production in A. oryzae using the sodM promoter led to secretion of approximately 1 g/l-broth in Czapek-Dox medium for 3 d. Fucose lectin production in A. oryzae using the sodM promoter led to overexpression as a specific and abundant intracellular protein. 相似文献
996.
Yamashita D Kohzuki H Kitagawa Y Nakashima T Kikuta A Takaki M 《American journal of physiology. Heart and circulatory physiology》2004,287(1):H54-H62
Left ventricular (LV) myocardial slices were isolated from murine hearts (300 microm thick) and were stimulated at 1 Hz without external load. Mean myocardial slice O(2) consumption (MVo(2)) per minute (mMVo(2)) without stimulation was 0.97 +/- 0.14 ml O(2).min(-1).100 g LV(-1) and mean mMVo(2) with stimulation increased to 1.80 +/- 0.17 ml O(2).min(-1).100 g LV(-1) in normal Tyrode solution. Mean DeltamVo(2) (the mMVo(2) with stimulation - the mMVo(2) without stimulation) was 0.83 +/- 0.12 ml O(2).min(-1).100 g LV(-1). There were no differences between mean mMVo(2) with and without stimulation in Ca(2+)-free solution. The increases in extracellular Ca(2+) concentrations up to 14.4 mM did not affect the mMVo(2) without stimulation but significantly increased the mMVo(2) with stimulation up to 140% of control. The DeltamMVo(2) significantly increased up to 190% of the control in a dose-dependent manner. In contrast, the shortening did not increase in a dose-dependent manner. Cyclopiazonic acid (CPA; 30 microM) significantly reduced the DeltamMVo(2) to 0.27 +/- 0.06 ml O(2).min(-1).100 g LV(-1) (35% of control). The combination of 5 mM 2,3-butanedione monoxime (BDM) and 30 microM CPA did not further decrease DeltamMVo(2). Although BDM (3-5 mM) decreased the DeltamMVo(2) by 28-30% of control in a dose-independent manner, 3-5 mM BDM decreased shortening in a dose-dependent manner. Our results indicate that the DeltamMVo(2) of mouse LV slices during shortening under mechanically unloaded conditions consists of energy expenditure for total Ca(2+) handling during excitation-contraction coupling, basal metabolism, but no residual cross-bridge cycling. 相似文献
997.
Kitagawa Y Yamashita D Ito H Takaki M 《American journal of physiology. Heart and circulatory physiology》2004,287(1):H277-H285
The aim of the present study was to evaluate specifically left ventricular (LV) function in rat hearts as they transition from the normal to hypertrophic state and back to normal. Either isoproterenol (1.2 and 2.4 mg.kg(-1).day(-1) for 3 days; Iso group) or vehicle (saline 24 microl.day(-1) for 3 days; Sa group) was infused by subcutaneous implantation of an osmotic minipump. After verifying the development of cardiac hypertrophy, we recorded continuous LV pressure-volume (P-V) loops of in situ ejecting hypertrophied rat hearts. The curved LV end-systolic P-V relation (ESPVR) and systolic P-V area (PVA) were obtained from a series of LV P-V loops in the Sa and Iso groups 1 h or 2 days after the removal of the osmotic minipump. PVA at midrange LV volume (PVA(mLVV)) was taken as a good index for LV work capability (13, 15, 20, 21). However, in rat hearts during remodeling, whether PVA(mLVV) is a good index for LV work capability has not been determined yet. In the present study, in contrast to unchanged end-systolic pressure at midrange LV volume, PVA(mLVV) was significantly decreased by isoproterenol treatment relative to saline; however, these measurements were the same 2 days after pump removal. Simultaneous treatment with a beta(1)-blocker, metoprolol (24 mg.kg(-1).day(-1)), blocked the formation of cardiac hypertrophy and thus PVA(mLVV) did not decrease. The reversible changes in PVA(mLVV) reflect precisely the changes in LV work capability in isoproterenol-induced hypertrophied rat hearts mediated by beta(1)-receptors. These results indicate that the present approach may be an appropriate strategy for evaluating the effects of antihypertrophic and antifibrotic modalities. 相似文献
998.
Miura Y Kataoka H Joh T Tada T Asai K Nakanishi M Okada N Okada H 《Microbiology and immunology》2004,48(2):137-145
Alpha-fetoprotein (AFP) expression is observed in embryonic tissues and, the expression of this protein is absent in normal adult tissues. The re-elevation of serum AFP strongly suggests generation of a malignant tumor in an adult. We demonstrated here that AFP-producing gastric cancer (AFP-gastric cancer) could be treated by a combination therapy with a low dose of Mitomycin-C (MMC) and lymphokineactivated killer T (LAK-T) cells. Treatment with MMC of AFP-gastric cancer cells enhanced their susceptibility to LAK-T cells and induced ATBF1 gene expression. We revealed here a novel signal pathway for regulation of the cell cycle of AFP-gastric cancer cells through ATBF1, which enhances the promoter activity of the p21 (Waf1/Cip1) gene. Immunoprecipitation revealed the direct interaction between ATBF1 and p53. Overexpressed ATBF1 stimulated p21 (Waf1/Cip1) promoter activity up to 4-fold compared with basal activity. The expression level of ATBF1 mRNA was doubled by MMC (0.05 microg/ml) treatment. The MMC treatment and ATBF1 overexpression synergistically activated the p21 (Waf1/Cip1) promoter activity in a dose-dependent manner up to 7-fold compared with basal activity. 相似文献
999.
Akamatsu S Nakajima K Ishisaki A Matsuno H Tanabe K Takei M Takenaka M Hirade K Yoshimi N Suga H Oiso Y Kato K Kozawa O 《Journal of cellular biochemistry》2004,92(6):1203-1211
Administration of arginine vasopressin (AVP) time-dependently induced the phosphorylation of heat shock protein 27 (HSP27) at Ser-15 and Ser-85 in smooth muscle of aorta in vivo. The AVP-induced phosphorylation of HSP27 at Ser-15 and Ser-85 was inhibited by a V1a receptor antagonist but not by a V2 receptor antagonist. In cultured aortic smooth muscle A10 cells, AVP markedly stimulated the phosphorylation of HSP27 at Ser-15 and Ser-85. The AVP-induced phosphorylation of HSP27 was attenuated by SB203580 and PD169316, inhibitors of p38 mitogen-activated protein (MAP) kinase, but not by PD98059, a MEK inhibitor. These results strongly suggest that AVP phosphorylates HSP27 via p38 MAP kinase in aortic smooth muscle cells. 相似文献
1000.