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排序方式: 共有712条查询结果,搜索用时 20 毫秒
71.
Keisuke Sugimoto Shuhei Tsuchiya Masahiro Omori Ryo Matsuda Masahito Fujio Kensuke Kuroda Masazumi Okido Hideharu Hibi 《Biochemistry and Biophysics Reports》2016
Osseointegration is the structural and functional connection between bone tissues and implants such as titanium dioxide (TiO2). The bone-TiO2 interface is thought to contain proteoglycans. However, exhaustive analysis of the proteins in this layer has not been performed. In this study, we evaluated the bone protein adhered on the surface of TiO2 comprehensively. Pig bone protein was extracted by sequential elutions with guanidine, 0.1 M EDTA, and again with guanidine. The proteins obtained from these extractions were allowed to adhere to an HPLC column packed with TiO2 and were eluted with 0.2 M NaOH. The eluted proteins were identified by LC/MS/MS and included not only proteoglycans but also other proteins such as extracellular matrix proteins, enzymes, and growth factors. Calcium depositions were observed on TiO2 particles incubated with bone proteins, guanidine-extracted proteins adhered to TiO2 displayed significantly high amounts of calcium depositions. 相似文献
72.
Yugo Tagaito Shiroh Isono John E Remmers Atsuko Tanaka Takashi Nishino 《Journal of applied physiology》2007,103(4):1379-1385
Lung volume dependence of pharyngeal airway patency suggests involvement of lung volume in pathogenesis of obstructive sleep apnea. We examined the structural interaction between passive pharyngeal airway and lung volume independent of neuromuscular factors. Static mechanical properties of the passive pharynx were compared before and during lung inflation in eight anesthetized and paralyzed patients with sleep-disordered breathing. The respiratory system volume was increased by applying negative extrathoracic pressure, thereby leaving the transpharyngeal pressure unchanged. Application of -50-cmH(2)O negative extrathoracic pressure produced an increase in lung volume of 0.72 (0.63-0.91) liter [median (25-75 percentile)], resulting in a significant reduction of velopharyngeal closing pressure of 1.22 (0.14-2.03) cmH(2)O without significantly changing collapsibility of the oropharyngeal airway. Improvement of the velopharyngeal closing pressure was directly associated with body mass index. We conclude that increase in lung volume structurally improves velopharyngeal collapsibility particularly in obese patients with sleep-disordered breathing. 相似文献
73.
Mako Narisawa-Saito Satoshi Kimura Naoshi Fujiwara Takashi Oite Koki Shimoji Fujio Shimizu 《Journal of cellular physiology》1996,168(3):705-710
Thy-1 glycoprotein is expressed in rat glomerular mesangial cells, and anti-Thy-1 nephritis induced by anti-Thy-1 antibodies is a model of human renal diseases. In this study, we examined Thy-1-mediated biological reactions in cultured rat glomerular mesangial cells utilizing two anti-Thy-1 monoclonal antibodies (mAbs), 1-22-3 and OX-7. Incubation of the cells with these mAbs resulted in increased inositol trisphosphate (IP3) levels. The rise in IP3 produced by mAb 1-22-3 was greater than that produced by mAb OX-7 at the same dose. Incubation of mesangial cells with these mAbs resulted in an increase in the intracellular free calcium concentration ([Ca2+]i). mAb 1-22-3 induced a sustained increase in [Ca2+]i, while that induced by mAb OX-7 lasted 1-2 min, then decreased to the basal level. An transient increase in [Ca2+]i was also observed in Ca2+-free medium, indicating that these [Ca2+]i increases are due to release of Ca2+ from internal stores by IP3 without calcium flux across cell membrane. When cells were pretreated with protein tyrosine kinase (PTK) inhibitors (herbimycin A or genistein), Thy-1-mediated increases in [Ca2+]i were inhibited. These data suggest that Thy-1 induces the production of IP3 (including inositol 1,4,5-triphosphate, an intracellular Ca2+-releasing factor) and that PTKs may contribute to the Thy-1-mediated elevation of [Ca2+]i which presumably results from phospholipase C activation following Thy-1-mediated signaling in rat mesangial cells. © 1996 Wiley-Liss, Inc. 相似文献
74.
Akihiro Kinoshita Tomoo Tamura Chiharu Aoki Tohru Nakanishi Shizuo Sobue Fujio Suzuki Kojiro Takahashi Masaharu Takigawa 《Cell biology international》1995,19(8):647-654
Endothelin (ET) receptors on chondrocytes were demonstrated using cultured rabbit costal chondrocytes. After crosslinking the receptors on the cells with 125 I-ET-1, two major bands of 43 kDa and 46 kDa were separated by SDS-PAGE. Scatchard analysis demonstrated two classes of ET receptors with Kd values of 1 × 10?10 M and 5 × 10?9 M. The numbers of high- and low- affinity receptors were 1 × 104 and 2 × 105 per cell, respectively. The binding of ET-1 to chondrocytes was increased by treatment with PTH, DBcAMP, TGF-β1, IL-1β, RA and EGF. ET-1 stimulated DNA synthesis in cultured rabbit chondrocytes. ET-1 also stimulated calcium incorporation through the cell membrane of chondrocytes. These findings indicate that ET-1 has a physiological effect on chondrocytes via its receptors on the cells. 相似文献
75.
Murayama R Akanuma G Makino Y Nanamiya H Kawamura F 《Bioscience, biotechnology, and biochemistry》2004,68(8):1672-1680
Using a simple semi-synthetic competence and sporulation medium (CSM), we found evidence that Bacillus subtilis cells transformed in the competence phase can sporulate, indicating that genetic information acquired during the competence phase is inherited by the next generation after germination of the transformed spores. Moreover, the results from mixed cell culture experiments suggest that spontaneous genetic transformation can occur between competent cells and DNA released from lysed cells in the natural environment. We also found evidence that the spontaneous transformation system can be used for genetic mapping in B. subtilis. 相似文献
76.
77.
Taurine inhibits apoptosis by preventing formation of the Apaf-1/caspase-9 apoptosome 总被引:5,自引:0,他引:5
Takatani T Takahashi K Uozumi Y Shikata E Yamamoto Y Ito T Matsuda T Schaffer SW Fujio Y Azuma J 《American journal of physiology. Cell physiology》2004,287(4):C949-C953
Cardiomyocyte apoptosis contributes to cell death during myocardial infarction. One of the factors that regulate the degree of apoptosis during ischemia is the amino acid taurine. To study the mechanism underlying the beneficial effect of taurine, we examined the interaction between taurine and mitochondria-mediated apoptosis using a simulated ischemia model with cultured rat neonatal cardiomyocytes sealed in closed flasks. Exposure to medium containing 20 mM taurine reduced the degree of apoptosis following periods of ischemia varying from 24 to 72 h. In the untreated group, simulated ischemia for 24 h led to mitochondrial depolarization accompanied by cytochrome c release. The apoptotic cascade was also activated, as evidenced by the activation of caspase-9 and -3. Taurine treatment had no effect on mitochondrial membrane potential and cytochrome c release; however, it inhibited ischemia-induced cleavage of caspase-9 and -3. Taurine loading also suppressed the formation of the Apaf-1/caspase-9 apoptosome and the interaction of caspase-9 with Apaf-1. These findings demonstrate that taurine effectively prevents myocardial ischemia-induced apoptosis by inhibiting the assembly of the Apaf-1/caspase-9 apoptosome. ischemia; cultured cardiomyocytes 相似文献
78.
Glycerol, a linear triol, is a sweet tastant for mammals but it has not previously been recognized to stimulate the sense of taste in insects. Here we show by electrophysiological experimentation that it effectively stimulates the labellar sugar receptor cell of Drosophila. We also show that in accord with the electrophysiological observations, the behavioral feeding response to glycerol is dose dependent. 3-Amino-1,2-propanediol inhibited the response of the sugar receptor cell to glycerol, specifically and competitively, while it had almost no effect on responses to sucrose, D-glucose, D-fructose and trehalose. In the null Drosophila mutant for the trehalose receptor (DeltaEP19), the response to glycerol showed no change, in sharp contrast with a characteristic drastic decrease in the response to trehalose. The glycerol concentration-response curves for I-type and L-type labellar hairs were statistically indistinguishable, while those for sucrose, D-glucose, D-fructose and trehalose were clearly different. These all indicate the presence of a specific receptor site for glycerol. The glycerol site was characterized by comparing the effectiveness of various derivatives of glycerol. Based on this structure-taste relationship of glycerol, a model is proposed for the glycerol site including three subsites and two steric barriers, which cannot accommodate carbon-ring containing sugars such as D-glucose. 相似文献
79.
Tatsumi R Seio K Fujio M Katayama J Horikawa T Hashimoto K Tanaka H 《Bioorganic & medicinal chemistry letters》2004,14(14):3781-3784
A series of 3-substituted 1-azabicyclo[2.2.2]octanes was discovered as the alpha7 nicotinic acetylcholine (alpha7) receptor agonists. It was found that (+)-3-[2-(benzo[b]thiophen-2-yl)-2-oxoethyl]-1-azabicyclo[2.2.2]octane (+)-15b has potent agonistic activity for the alpha7 receptor. 相似文献
80.
Saeki Y Isono E Oguchi T Shimada M Sone T Kawahara H Yokosawa H Toh-e A 《Genes & genetic systems》2004,79(2):77-86
We constructed polyubiquitin derivatives that contain a tandem repeat of ubiquitins and were insensitive to ubiquitin hydrolases. They were designated tandem ubiquitin (tUb) with the number of repeats, such as tUb2. When tUbs were expressed under the control of the GAL1 promoter in the wild-type yeast strain, growth was strongly inhibited. Under these conditions, the degradation of N-end rule substrates, a UFD substrate and Gcn4 was inhibited, indicating that the tUb inhibits 26S proteasome activity. Consistent with this, tUb binds to the 26S proteasome. We showed that tUb inhibited the in vitro degradation of polyubiquitinylated Sic1 by the 26S proteasome. When tUB6 messenger RNA was injected into Xenopus embryos, cell division was inhibited, suggesting that tUb can be used as a versatile inhibitor of the 26S proteasome. 相似文献