排序方式: 共有101条查询结果,搜索用时 15 毫秒
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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
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A G protein-coupled receptor responsive to bile acids 总被引:6,自引:0,他引:6
Kawamata Y Fujii R Hosoya M Harada M Yoshida H Miwa M Fukusumi S Habata Y Itoh T Shintani Y Hinuma S Fujisawa Y Fujino M 《The Journal of biological chemistry》2003,278(11):9435-9440
So far some nuclear receptors for bile acids have been identified. However, no cell surface receptor for bile acids has yet been reported. We found that a novel G protein-coupled receptor, TGR5, is responsive to bile acids as a cell-surface receptor. Bile acids specifically induced receptor internalization, the activation of extracellular signal-regulated kinase mitogen-activated protein kinase, the increase of guanosine 5'-O-3-thio-triphosphate binding in membrane fractions, and intracellular cAMP production in Chinese hamster ovary cells expressing TGR5. Our quantitative analyses for TGR5 mRNA showed that it was abundantly expressed in monocytes/macrophages in human and rabbit. Treatment with bile acids was found to suppress the functions of rabbit alveolar macrophages including phagocytosis and lipopolysaccharide-stimulated cytokine productions. We prepared a monocytic cell line expressing TGR5 by transfecting a TGR5 cDNA into THP-1 cells that did not express TGR5 originally. Treatment with bile acids suppressed the cytokine productions in the THP-1 cells expressing TGR5, whereas it did not influence those in the original THP-1 cells, suggesting that TGR5 is implicated in the suppression of macrophage functions by bile acids. 相似文献
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Assembly of archaeal signal recognition particle from recombinant components 总被引:9,自引:0,他引:9 下载免费PDF全文
Signal recognition particle (SRP) takes part in protein targeting and secretion in all organisms. Searches for components of archaeal SRP in primary databases and completed genomes indicated that archaea possess only homologs of SRP RNA, and proteins SRP19 and SRP54. A recombinant SRP was assembled from cloned, expressed and purified components of the hyperthermophilic archaeon Archaeoglobus fulgidus. Recombinant Af-SRP54 associated with the signal peptide of bovine pre-prolactin translated in vitro. As in mammalian SRP, Af-SRP54 binding to Af-SRP RNA required protein Af-SRP19, although notable amounts bound in absence of Af-SRP19. Archaeoglobus fulgidus SRP proteins also bound to full-length SRP RNA of the archaeon Methanococcus jannaschii, to eukaryotic human SRP RNA, and to truncated versions which corresponded to the large domain of SRP. Dependence on SRP19 was most pronounced with components from the same species. Reconstitutions with heterologous components revealed a significant potential of human SRP proteins to bind to archaeal SRP RNAs. Surprisingly, M.jannaschii SRP RNA bound to human SRP54M quantitatively in the absence of SRP19. This is the first report of reconstitution of an archaeal SRP from recombinantly expressed purified components. The results highlight structural and functional conservation of SRP assembly between archaea and eucarya. 相似文献
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Distinct Roles of Urinary Liver-Type Fatty Acid-Binding Protein in Non-Diabetic Patients with Anemia
Naohiko Imai Takashi Yasuda Atsuko Kamijo-Ikemori Yugo Shibagaki Kenjiro Kimura 《PloS one》2015,10(5)
BackgroundVarious stresses including ischemia are known to up-regulate renal L-FABP gene expression and increase the urinary excretion of L-FABP. In diabetic patients with anemia, the urinary excretion of L-FABP is significantly increased. We studied the clinical significance of urinary L-FABP and its relationship with anemia in non-diabetic patients.ResultsUrinary L-FABP levels were significantly higher in patients with anemia compared to those in patients without anemia. Similarly, the urinary L-FABP levels were significantly higher in patients with albuminuria compared to those in patients without albuminuria. Urinary L-FABP levels correlated with urinary albumin-to-creatinine ratios, estimated glomerular filtration rates, body mass index, and hemoglobin levels. Multivariate linear regression analysis determined that hemoglobin levels (β = -0.249, P = 0.001) and urinary albumin-to-creatinine ratios (β = 0.349, P < 0.001) were significant predictors of urinary L-FABP levels.ConclusionsUrinary L-FABP is strongly associated with anemia in non-diabetic patients. 相似文献
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Organic pollution in eutrophic river water dammed by estuary weirs was studied in the Shin and Kasuga rivers of the Shikoku
region, Japan. Both rivers are located in a low-precipitation region of Japan. The investigation was performed at intervals
of 3–14 days from 12 July 2002 to 13 July 2003. The annual averages of chlorophyll a concentration were approximately 150 and 40 μg L−1 in the Shin and Kasuga rivers, respectively. The concentration often exceeded 500 μg L−1 in the Shin River in winter. Dissolved oxygen saturation exhibited marked variation. High and low values, i.e., >150% in
the surface water layer and 0% in the bottom water layer, were occasionally observed. Dissolved methane concentrations >2,000 nM
were often observed from spring to fall. In both rivers, the serious organic substance pollution was confirmed through 1 year. 相似文献
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Matthew J Campen Yugo Tagaito Todd P Jenkins Alex Balbir Christopher P O'Donnell 《Journal of applied physiology》2005,99(3):807-813
Heart rate variability (HRV) is a well-characterized, noninvasive means of assessing cardiac autonomic nervous system activity. This study examines the basic cardiac responses to hypoxic and hypercapnic challenges in seven strains of commonly used inbred mice (A/J, BALB/cJ, C3H/HeJ, C57BL/6J, CBA/J, DBA/2J, and FVB/J). Adult male mice, 8-12 wk of age, were chronically instrumented to a femoral artery catheter for the continuous measurement of systemic arterial blood pressure and heart rate. Mice were exposed to multiple 4-min periods of hypoxia (10% O2), hypercapnia (5% CO2), and combined hypoxia/hypercapnia (10% O2 + 5% CO2). HRV was derived from pulse intervals of the blood pressure tracings. Hypoxia induced increases in high-frequency HRV power and decreased low-frequency (LF) HRV power in most strains. Hypercapnia led to decreased high-frequency HRV power and increased LF HRV power in most strains. Strain differences were most notable in regard to the concomitant exposures of hypoxia and hypercapnia, with FVB/J mice mirroring their own response to hypercapnia alone, whereas CBA/J mice mirrored their own responses to hypoxia. As blood pressure is most likely the driving factor for heart rate changes via the baroreflex pathway, it is interesting that LF, considered to reflect cardiac sympathetic activity, was negatively correlated with heart rate, suggesting that LF changes are driven by baroreflex oscillation and not necessarily by absolute sympathetic or parasympathetic activity to the heart. These findings suggest that genetic background can influence the centrally mediated cardiovascular responses to basic hypoxic and hypercapnic challenges. 相似文献
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Okada Y Imendra KG Miyazaki T Hotokezaka H Fujiyama R Zeredo JL Toda K 《Cellular and molecular neurobiology》2007,27(6):771-781
The effect of calcium-sensing receptor (CaR) agonists on frog gustatory responses was studied using glossopharyngeal nerve
recording and whole-cell patch-clamp recording of isolated taste disc cells. Calcimimetic NPS R-467 dissolved in normal saline
solution elicited a large transient response in the nerve. The less active enantiomer of the compound, NPS S-467 induced only
a small neural response. The EC50 for NPS R-467 was about 20 μM. Cross-adaptation experiments were performed to examine the effect of 30 μM NPS R-467 and 100 μM
quinine on the gustatory neural response. The magnitude of the R-467-induced response after adaptation to quinine was approximately
equal to that after adaptation to normal saline solution, indicating that the receptor site for NPS R-467 is different from
the site for quinine. NPS R-467 (100 μM) also induced an inward current accompanied with conductance increase and large depolarization
in two (13%) of 15 rod cells, and a sustained decrease in outward current and small depolarization in six (40%) other rod
cells. NPS S-467 (100 μM) induced a sustained decrease in outward current and depolarization in five (50%) of 10 rod cells.
Another calcimimetic cinacalcet (100 μM) induced an inward current accompanied with conductance increase in three (27%) of
11 rod cells. The results suggest that NPS R-467 induces neural responses through cell responses unrelated to a resting K+ conductance decrease. 相似文献