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981.
982.
Segawa S Takata Y Kaneda H Watari J 《Bioscience, biotechnology, and biochemistry》2007,71(6):1577-1581
The antiallergic properties of a hop water extract (HWE) were studied by evaluating the Evans blue leakage from ICR mice caused by compound 48/80 stimulation, and the histamine release from ovalbumin (OVA)-sensitized BALB/c mice. An oral administration of HWE significantly inhibited the vascular permeability and histamine release. HWE itself did not have any influence on the total and antigen-specific immunoglobulin E (IgE) production in OVA-sensitized mice. These results indicate that HWE exerted an antiallergic effect by inhibiting the release of chemical mediators from mast cells and basophiles. 相似文献
983.
Kawai M Nakamura H Sakurada I Shimokawa H Tanaka H Matsumizu M Ando K Hattori K Ohta A Nukui S Omura A Kawamura M 《Bioorganic & medicinal chemistry letters》2007,17(20):5533-5536
Novel NR2B antagonists with an amide tether were found by an approach to avoid pharmacophoric similarity to dofetilide. Structure-activity relationship investigation led to N-[cis-4-hydroxy-4-(5-hydroxypyridin-2-yl)cyclohexyl]-3-henylpropanamide as an orally active NR2B-subtype selective N-methyl-D-aspartate (NMDA) receptor antagonist with very weak HERG (human ether-a-go-go related gene) binding (IC(50)> 30 microM). This compound exhibited potent in vivo anti-allodynic activity in the mouse partial sciatic nerve ligation (PSL) model (minimum effective dose=10 mg/kg, po). 相似文献
984.
Urata H Nomura K Wada S Akagi M 《Biochemical and biophysical research communications》2007,360(2):459-463
One of the intriguing applications of aptamers is sensing molecules. In principle, an aptamer can specifically recognize and bind to a unique ligand, leading to a structural change of an aptamer. By acquiring information for the structural change, the detection of the ligand can be achieved. To design and explore an aptamer molecule to detect adenosine, we have synthesized some ATP aptamer variants labeled with donor and acceptor fluorophores. Although the fluorescent response of the aptamer variants was highly dependent on experimental temperature, we have found one of the variants showing suitable fluorescent response by titration with adenosine. The aptamer variant showed remarkable selectivity for adenosine over the other ribonucleosides. On the other hand, the enantio-specificity of the aptamer variant in the ligand recognition was not enough to selectively detect d-adenosine over l-adenosine. 相似文献
985.
Taniguchi K Nomura K Hata Y Nishimura T Asami Y Kuroda A 《Biotechnology and bioengineering》2007,96(6):1023-1029
Targeting functional proteins to specific sites on a silicon device is essential for the development of new biosensors and supramolecular assemblies. Using intracellular lysates of several bacterial strains, we found that ribosomal protein L2 binds tightly to silicon particles, which have surfaces that are oxidized to silica. A fusion of E. coli L2 and green fluorescence protein adsorbed to the silica particles with a K(d) of 0.7 nM at pH 7.5 and also adsorbed to glass slides. This fusion protein was retained on the glass slide even after washing for 24 h with a buffer containing 1 M NaCl. We mapped the silica-binding domains of E. coli L2 to amino acids 1-60 and 203-273. These two regions seemed to cooperatively mediate the strong silica-binding characteristics of L2. A fusion of L2 and firefly luciferase also adsorbed on the glass slide. This L2 silica-binding tag, which we call the "Si-tag," can be used for one-step targeting of functional proteins on silica surfaces. 相似文献
986.
A convenient chemoenzymatic procedure for the synthesis of p-aminophenyl glycosides of sialyl N-acetyllactosaminide has been developed from p-nitrophenyl N-acetyl-beta-D-glucosaminide as starting material through three steps: synthesis of p-nitrophenyl N-acetyllactosaminide with beta-D-galactosidase, chemical reduction of the p-nitrophenyl group, and sialylation with sialyltransferase. The p-aminophenyl glycosides were then successfully biotin-labeled through the coupling with N-(+)-biotinyl-6-aminohexanoic acid to afford biotinylated oligosaccharides with an aminohexanosyl group and phenyl group as the spacers between the biotin and glycan. Furthermore, the biotin-labeled sugars were shown to be useful for immobilization and assay of the carbohydrate-lectin interactions by an optical biosensor based on surface plasmon resonance. 相似文献
987.
Nitric oxide (NO) is a new clinical biomarker of survival in the elderly patients and its efficacy might be nearly equal to albumin. 总被引:1,自引:0,他引:1
Masako Osawa Toshio Hayashi Hideki Nomura Jun Funami Asaka Miyazaki Louis J Ignarro Akihisa Iguchi 《Nitric oxide》2007,16(1):157-163
BACKGROUND: For elderly patients, the consideration of prognostic factors is very important, but there have been few reports about the potential use of vasoactive substances as prognostic markers in the elderly. OBJECTIVE: We assessed endocrinological substances, such as plasma NO(x) (metabolites of NO), as the prognostic marker in elderly. We compared their efficacy with that of such well-known markers as albumin and pro-inflammatory cytokines such as IL-6. METHODS: The patients were recruited consequently from the clinics of Nagoya University Hospital or related home care services facilities. One hundred and twenty seven elderly aged 65 and older were registered. Biochemical analyses such as albumin, total cholesterol, BNP, and NO(x) were measured upon enrollment. The main outcome was the survival rate. RESULTS: Forty-six patients died during the follow-up period. Mann-Whitney's U-test showed that the levels of age, hemoglobin, total protein, serum albumin, serum creatinine, total cholesterol, HDL-cholesterol, LDL-cholesterol, high sensitive CRP, NO(x), IL-6, and TNF-alpha were significantly different between the living and deceased subjects. Among the dependent variables in the logistic regression analyses, only albumin and NO(x) were significantly different. In the Kaplan-Meier analyses of mortality, the prognosis of patients in 3rd and 4th quartile of NO(x) was significantly worse than that in 1st or 2nd quartile. CONCLUSION: NO(x) has potential both as a vascular marker and as a marker for predicting survival in elderly. In the latter role, it may be as effective as albumin. 相似文献
988.
989.
Kazumasa Yamada Hirotaka Katsura Mary‐Hlne Noël Mutsuo Ichinomiya Akira Kuwata Shinya Sato Shinya Yoshikawa 《Journal of phycology》2019,55(1):196-203
Triparma laevis f. inornata is a unicellular alga belonging to the Bolidophyceae, which is most closely related to diatoms. Like diatoms, T. laevis f. inornata has a siliceous cell wall. The cell wall of T. laevis f. inornata consists of four round plates (three shields and one ventral plate) and one dorsal and three girdle plates. But, unlike diatoms, T. laevis f. inornata cells can grow when concentrations of silica are depleted. We took advantage of this ability, using TEM to study the ontogeny of the siliceous plate, pattern center formation, and development. Two types of pattern centers (annulus and sternum) were observed in the early and middle stage of plate formation. During their formation, the annuli were initially crescent‐shaped but eventually their ends fused to make a ring. Only outward silica deposition of the branching ribs occurred on the growing annulus until it became a ring, resulting in an unfilled circle inside the annulus. The pattern center of the shield plate was always an annulus, but in ventral plates both annulus and sternum were observed. The annuli and sterna in T. laevis f. inornata round plates were very similar to the annuli and sterna in diatom valves. These results suggested that the round plates of Parmales are homologous to diatom valves. This information on the plate ontogeny of T. laevis f. inornata provides new insights into the evolution of the siliceous cell wall in the Parmales and diatoms. 相似文献