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531.
The influence of age on the time-dependent difference in urinary excretion of furosemide, a loop diuretic agent, was examined in this longitudinal study. Male Wistar rats were maintained under conditions of light from 07:00 to 19:00 h and dark from 19:00 to 07:00 h. Furosemide (30 mg/kg) was given orally at 12:00 h (day trial) or 00:00 h (night trial) to rats at 3 months of age, and urine was collected for 8 h after dosage. Thereafter, the identical protocol was repeated using the same animals at 6, 9, 12, 15, 18, and 21 months of age. The urinary excretion of furosemide was significantly greater in the day than in the night trial at 3 months of age. Such a time-dependent difference was observed for up to 15 months, but disappeared at 18 and 21 months of age. The time-dependent difference in urinary excretion of furosemide (day trial — night trial) decreased gradually throughout the observation period of the study. These results suggest that the time-dependent difference in the urinary excretion of furosemide diminishes during the aging process and disappears by 18 months of age in male Wistar rats. 相似文献
532.
Effects of a thromboxane A2 receptor antagonist (S-1452) on bronchoconstriction induced by inhaled leukotriene C4 and a leukotriene receptor antagonist (AS-35) on bronchoconstriction caused by inhalation of a thromboxane A2 mimetic (STA2) were studied in anesthetized, artificially ventilated guinea pigs in order to examine the interaction of thromboxane A2 and leukotrienes in airways. 0.01-1.0 mu g/ml of leukotriene C4 and 0.1-1.0 mu g/ml of STA 2 inhaled from ultrasonic nebulizer developed for small animals caused dose-dependent increase of pressure at the airway opening (Pao) which is considered to be an index representing bronchial response. Pretreatment of the animals with inhaled S-1452 (0.01, 0.033 mg/ml) significantly reduced the airway responses produced by 0.01,0.033,0.1,0.33 and 1.0 mu g/ml of leukotriene C4 in a dose dependent manner. While pretreatment with inhaled AS-35 (1mg) did not affect the STA2 dose-response curve. These findings suggest that leukotriene C4 activates thromboxane A2 generation while thromboxane A2 does not influence 5-lipoxygenase pathway in the airways. 相似文献
533.
Hair growth is a highly regulated cyclical process. Immunosuppressive immunophilin ligands such as cyclosporin A (CsA) and FK506 are known as potent hair growth modulatory agents in rodents and humans that induce active hair growth and inhibit hair follicle regression. The immunosuppressive effectiveness of these drugs has been generally attributed to inhibition of T cell activation through well-characterized pathways. Specifically, CsA and FK506 bind to intracellular proteins, principally cyclophilin A and FKBP12, respectively, and thereby inhibit the phosphatase calcineurin (Cn). The calcineurin (Cn)/NFAT pathway has an important, but poorly understood, role in the regulation of hair follicle development. Here we show that a novel-splicing variant of calcineurin Aß CnAß-FK, which is encoded by an intron-retaining mRNA and is deficient in the autoinhibitory domain, is predominantly expressed in mature follicular keratinocytes but not in the proliferating keratinocytes of rodents. CnAß-FK was weakly sensitive to Ca2+ and dephosphorylated NFATc2 under low Ca2+ levels in keratinocytes. Inhibition of Cn/NFAT induced hair growth in nude mice. Cyclin G2 was identified as a novel target of the Cn/NFATc2 pathway and its expression in follicular keratinocytes was reduced by inhibition of Cn/NFAT. Overexpression of cyclin G2 arrested the cell cycle in follicular keratinocytes in vitro and the Cn inhibitor, cyclosporin A, inhibited nuclear localization of NFATc2, resulting in decreased cyclin G2 expression in follicular keratinocytes of rats in vivo. We therefore suggest that the calcineurin/NFAT pathway has a unique regulatory role in hair follicle development. 相似文献
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535.
Emília R. Vaz Patrícia T. Fujimura Galber R. Araujo Carlos A. T. da Silva Rangel L. Silva Thiago M. Cunha M?nica Lopes-Ferreira Carla Lima Márcio J. Ferreira Jair P. Cunha-Junior Ernesto A. Taketomi Luiz R. Goulart Carlos Ueira-Vieira 《PloS one》2015,10(8)
The transforming growth factor beta 1 (TGF-β1) is a pleiotropic cytokine with multiple roles in development, wound healing, and immune regulation. TGF-β1-mediated immune dysfunction may lead to pathological conditions, such as inflammation. Chronic inflammatory process is characterized by a continuous release of pro-inflammatory cytokines, and the inhibition or the blockage of these cytokines signaling pathways are considered a target treatment. In this context, despite the high numbers of TGF-β-targeted pathways, the inducible regulatory T cells (iTreg) to control inflammation seems to be a promising approach. Our aim was to develop novel peptides through phage display (PhD) technology that could mimic TGF-β1 function with higher potency. Specific mimetic peptides were obtained through a PhD subtraction strategy from whole cell binding using TGF-β1 recombinant as a competitor during elution step. We have selected a peptide that seems to play an important role on cellular differentiation and modulation of TNF-α and IL-10 cytokines. The synthetic pm26TGF-β1 peptide tested in PBMC significantly down-modulated TNF-α and up-regulated IL-10 responses, leading to regulatory T cells (Treg) phenotype differentiation. Furthermore, the synthetic peptide was able to decrease leukocytes rolling in BALB/C mice and neutrophils migration during inflammatory process in C57BL/6 mice. These data suggest that this peptide may be useful for the treatment of inflammatory diseases, especially because it displays potent anti-inflammatory properties and do not exhibit neutrophils’ chemoattraction. 相似文献
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537.
Micro‐ and Mesoporous Carbide‐Derived Carbon–Selenium Cathodes for High‐Performance Lithium Selenium Batteries 下载免费PDF全文
Jung Tae Lee Hyea Kim Martin Oschatz Dong‐Chan Lee Feixiang Wu Huan‐Ting Lin Bogdan Zdyrko Won Il Cho Stefan Kaskel Gleb Yushin 《Liver Transplantation》2015,5(1)
Nanocomposites of selenium (Se) and ordered mesoporous silicon carbide‐derived carbon (OM‐SiC‐CDC) are prepared for the first time and studied as cathodes for lithium‐selenium (Li‐Se) batteries. The higher concentration of Li salt in the electrolytes greatly improves Se utilization and cell cycle stability. Se‐CDC shows significantly better performance characteristics than Se‐activated carbon nanocomposites with similar physical properties. Se‐CDC also exhibits better rate performance and cycle stability compared to similarly produced sulfur (S)–CDC for Li/S batteries. 相似文献
538.
Mohammed El Behery Mika Fujimura Tetsunari Kimura Motonari Tsubaki 《Biochemistry and Biophysics Reports》2020
We studied human 101F6 protein to clarify its physiological function as a ferric reductase and its relationship to tumor suppression activity. We found for the first time that purified 101F6 both in detergent micelle state and in phospholipid bilayer nanodisc state has an authentic ferric reductase activity by single turnover kinetic analyses. The kinetic analysis on the ferrous heme oxidation of reduced 101F6 upon the addition of a ferric substrate, ferric ammonium citrate (FAC), showed concentration-dependent accelerations of its reaction with reasonable values of KM and Vmax. We further verified the authenticity of the ferric reductase activity of 101F6 using nitroso-PSAP as a Fe2+-specific colorimetric chelator. 101F6 in nanodisc state showed higher efficiency for FAC than in detergent micelle state. 相似文献
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540.
Fujimura Y Kurihara K Ida M Kosaka R Miura D Wariishi H Maeda-Yamamoto M Nesumi A Saito T Kanda T Yamada K Tachibana H 《PloS one》2011,6(8):e23426