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61.
Ayer Christopher G. Morita Kodai Fukui Sho Koizumi Itsuro 《Ichthyological Research》2022,69(2):261-266
Ichthyological Research - We evaluated the effects of a buccal cavity attaching Salmincola sp. on white-spotted charr Salvelinus leucomaenis by mark-recapture method to compare body condition,... 相似文献
62.
Yuji Kaneko Takuji Tsukamoto Tatsuhiko Kawarabayashi Masahiko Ikeda Hajime Sugimori 《Journal of molecular recognition : JMR》1996,9(3):233-238
Binding characteristics of β-adrenergic receptors of longitudinal muscle membranes isolated from different stages of pregnant rat myometrium were investigated using [3H]dihydroalprenolol. Between Days 15 and 21 of gestation, the ratio of β1- and β2-adrenergic receptors of longitudinal membranes was constant. The membranes were found to be predominant in β2-adrenergic receptors. The concentration of longitudinal muscle β-adrenergic receptors increased significantly during the last 7 days of gestation. Kinetic binding studies implied that the affinity of the membrane β-adrenergic receptors decreased through a slight decrease in the association rate and a large increase in the dissociation rate with progression of pregnancy. A Scatchard plot indicated that longitudinal muscle in β-adrenergic receptors on Days 15 and 18 constitute a single class of independent sites. By contrast, the dissociation kinetics, the convex downward curvature in a Scatchard plot and a Hill coefficient (h) of less than 1.00 of [3H] DHA binding to β-receptors of muscle on Day 21 suggested the existence of negatively cooperative multiple binding sites for β-adrenergic ligand. These results suggest that changes in the dynamics of uterus β-adrenergic receptors play an important role in the onset of labor. 相似文献
63.
64.
Li XA Kokame K Okubo K Shimokado K Tsukamoto Y Miyata T Kato H Yutani C 《Biochimica et biophysica acta》1999,1489(2-3):405-412
This study reports cloning and characterization of a human cDNA encoding a novel human zinc finger protein, ZFD25. ZFD25 cDNA is 6118 bp long and has an open reading frame of 2352 bp that encodes a 783 amino acid protein with 25 C2H2-type zinc fingers. The ZFD25 cDNA also contains a region with high sequence similarity to the Krüppel-associated box A and B domain in the 5'-untranslated region, suggesting that ZFD25 belongs to the Krüppel-associated box zinc finger protein family. The ZFD25 gene was localized to chromosome 7q11.2. Northern blot analysis showed that ZFD25 was expressed in a wide range of human organs. In cultured endothelial cells, the mRNA level was decreased upon serum starvation. 相似文献
65.
Quercetin, a widely distributed bioflavonoid, inhibited DNA synthesis in regenerating liver after partial hepatectomy. This inhibition was accompanied by apoptosis, evidenced by in situ end-labeling and gel electrophoresis of DNA fragmentation. Characteristic DNA fragmentation was detected as early as 2 h after injection. Northern blot analysis revealed that quercetin induced the increases in c-fos and p21WAF1CIP1 mRNA levels within 2 h. The expression of p21 protein was also enhanced, while p53 mRNA and protein levels were not affected by quercetin. These results suggest that quercetin-induced apoptosis is associated with the increase in c-fos mRNA level and the upregulation of p21 mRNA and protein expression, probably in a p53-independent pathway. 相似文献
66.
Taira E Nagino T Tsukamoto Y Okumura S Muraoka O Sakuma F Miki N 《Experimental cell research》1999,253(2):697-703
Gicerin is a cell adhesion molecule in the immunoglobulin (Ig) superfamily and is expressed abundantly during development in the nervous system. It has homophilic cell adhesion activity and also has heterophilic binding activity with NOF (neurite outgrowth factor) and mediates neurite extension. There are two isoforms of gicerin, one with a short (s-gicerin) and the other with a longer cytoplasmic domain (l-gicerin). We have reported that s-gicerin possesses stronger activities than l-gicerin during cell aggregation, in NOF-binding, and in neurite extension. In this study, we established cell lines which expressed a mutant-gicerin whose cytoplasmic domain was deleted and we compared the above three biological activities of the mutant-gicerin with those of s- and l-gicerin. We found that the mutant-gicerin retained all these activities, but the activities were weaker than those of s-gicerin and almost the same as those of l-gicerin. We concluded that the cytoplasmic domain of gicerin is not essential for optimal adhesive activities of gicerin, but might be involved in the regulation of its activities. 相似文献
67.
Tsukamoto M Murata Y Tada M Shimoishi Y 《Bioscience, biotechnology, and biochemistry》2004,68(4):920-923
A simple and sensitive spectrophotometric method combined with solid-phase extraction (SPE) for the simultaneous determination of sodium linear-dodecylbenzenesulfonate (DBS) and sodium dodecyl sulfate (SDS) is described. The C2 (ethyl group bonded silicagel) cartridge could be repeatedly used more than 500 times for SPE, and it enabled the anionic surfactants to be concentrated by 50-fold. The calibration graph for DBS was linear in the range from 1.6 x 10(-8) M to 5.0 x 10(-7) M and for SDS from 2.0 x 10(-9) M to 3.0 x 10(-7) M. The relative standard deviation (n=5) for 5.0 x 10(-7) M DBS was 3.1% and for 2.5 x 10(-7) M SDS was 1.7%. The proposed method was applied to the simultaneous determination of DBS and SDS in river-water samples. 相似文献
68.
Tsukamoto H Hishinuma T Suzuki N Tayama R Hiratsuka M Yoshihisa T Mizugaki M Goto J 《Prostaglandins & other lipid mediators》2004,73(3-4):191-213
Thiazolidinedione, peroxisome proliferator-activated receptor gamma (PPARgamma) agonist, has been used as an anti-diabetic drug and as an useful tool to elucidate multiple PPARgamma functions by in vitro and in vivo studies. We investigated the effects of thiazolidinediones on prostanoid production in lipopolysaccharide-stimulated cells. The high concentrations (>10 microM) of rosiglitazone and pioglitazone significantly increased lipopolysaccharide-stimulated prostanoid production such as thromboxane A2 and prostaglandin E2. However, PPARgamma antagonist could not inhibit them. In PPARgamma-deficient cells, thiazolidinediones increased prostaglandin E2 production. Thiazolidinediones increased arachidonic acid (AA) release from the cell membrane by not stimulating AA releasing process involving several phospholipase A2s but inhibiting AA reuptaking process. The expression of cyclooxygenase-1 and cyclooxygenase-2 were not affected by thiazolidinediones. In this study, we demonstrated that high concentrations of TZDs increased AA release by the inhibition of AA reuptaking process, leading to subsequent increase in the prostanoid production in a PPARgamma-independent manner. This mechanism provides useful information for the elucidation of multiple PPARgamma functions and diabetic drug therapy. 相似文献
69.
Butyrylcellulose (BuCell) with different degrees of butyrylation was synthesized as a membrane material for the separation of benzene/cyclohexane (Bz/Chx) mixtures. A BuCell membrane with a degree of butyrylation of 2.3 showed high benzene/cyclohexane selectivity for Bz/Chx mixtures by pervaporation. Both the permeation rate and the benzene/cyclohexane selectivity of the BuCell membrane increased with increasing benzene concentration in the feed mixture. The increase in the permeation rate resulted from an increase in the swelling of the membrane, and the increase in the benzene/cyclohexane selectivity can be attributed to an increase in the diffusion selectivity. With increasing degree of butyrylation of BuCell, the permeation rate increased; on the other hand, the benzene/cyclohexane selectivity decreased slightly. This result can qualitatively be explained by the degree of swelling, the density, and the contact angle of the BuCell membranes. The permeation and separation mechanism of Bz/Chx mixtures through BuCell membranes by pervaporation is discussed on the basis of the solution-diffusion model, which is typically applied for permeation through dense, nonporous membranes. 相似文献
70.
Syntheses and biological evaluation of novel quinuclidine derivatives as squalene synthase inhibitors 总被引:2,自引:0,他引:2
Ishihara T Kakuta H Moritani H Ugawa T Sakamoto S Tsukamoto S Yanagisawa I 《Bioorganic & medicinal chemistry》2003,11(11):2403-2414
Squalene synthase (E.C. 2.5.1.21) catalyses the reductive dimerization of two molecules of farnesyl diphosphate to form squalene and is involved in the first committed step in cholesterol biosynthesis. Inhibition of this enzyme is therefore an attractive target for hypocholesterolemic strategies. A series of quinuclidine derivatives incorporating a tricyclic system was synthesized and evaluated for their ability to inhibit squalene synthase in vitro. A 9H-fluorene moiety was found to be optimal as the tricyclic system for potent inhibitory activity. Improved activity can be achieved with a conformationally constrained three-atom linkage connecting the tricyclic system with the quinuclidine nucleus. Among these compounds, (Z)-3-[2-(9H-fluoren-2-yloxy)ethylidene]-quinuclidine hydrochloride 31 was found to be a potent inhibitor of squalene synthase derived from hamster liver and human hepatoma cells with IC(50) values of 76 and 48 nM, respectively. Oral dosing of compound 31 demonstrated effective reduction of plasma non-HDL cholesterol levels in hamsters. 相似文献