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Background and objective: Cytotoxic T-lymphocyte antigen 4 (CTLA-4) signalling of regulatory T cells regulates mucosal lymphocyte tolerance and differentiation, and may therefore have a beneficial effect in allergic diseases such as asthma. The aim of this study was to evaluate the effects of fluticasone propionate (FP) on CD4+CD25+ T cell co-expression of CTLA-4 in the sputum of mild asthmatic subjects. Methods: Eleven mild, stable asthmatic subjects completed a double-blind, randomized, cross-over, placebo-controlled study to compare the effects of 14 days 200 µg twice daily FP and placebo. Before and after treatment, airway hyperresponsiveness was measured, and sputum was induced for measurements of CTLA-4+CD4+CD25+ cells, eosinophils and levels of IL-10, IL-13 and transforming growth factor (TGF)-β Results: FP treatment increased co-expression of CTLA-4 on sputum CD4+CD25+ cells from a mean (SEM) of 7.9% (1.8) to 12.7% (3.3) after 14 days treatment (P < 0.05) compared with placebo. FP treatment also significantly increased IL-10 levels, reduced per cent sputum eosinophils, and reduced airway hyperresponsiveness (P < 0.05). There was a significant negative correlation between the change in airway hyperresponsiveness and per cent sputum eosinophils (P < 0.01), but no correlation with changes in CTLA-4+CD4+CD25+ cells (P > 0.05). There was no change in the levels of sputum IL-13 or TGF-β Conclusions: The percentage of airway CTLA-4+CD4+CD25+ cells increased after FP treatment, coincident with improvements in airway inflammation and hyperresponsiveness. Whether improved asthma assessments are related to the increase in CTLA-4+CD4+CD25+ cells and thus improved regulation of T-cell tolerance and differentiation will require a larger sample size to determine. The normalization of CTLA-4+CD4+CD25+ cells in asthma may contribute to the management of this disease.  相似文献   
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Melt-electrospinning is an eco-friendly method for producing ultra-fine fibers without using any solvent. We prepared webs of poly(ethylene terephthalate) (PET) through melt-electrospinning using CO2 laser irradiation for heating. The PET webs comprised ultra-fine fibers of uniform diameter (average fiber diameter = 1.66 μm, coefficient of variation = 19%). The co-existence of fibers with high and low molecular orientation was confirmed through birefringence measurements. Although the level of high orientation corresponded to that of commercial highly oriented yarn, crystalline diffraction was not observed in the wide-angle X-ray diffraction (WAXD) analysis of the webs. The crystallinity of the webs was estimated using differential scanning calorimetry (DSC). The fibers with higher birefringence did not exhibit any cold crystallization peak. After annealing the web at 116 °C for 5 min, a further increase in the birefringence of the fibers with higher orientation was observed. The WAXD results revealed that the annealed webs showed crystalline diffraction peaks with the orientation of the c-axis along the fiber axis. In summary, the formation of fibers with a unique non-crystalline structure with extremely high orientation was confirmed.  相似文献   
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BACKGROUND Autotaxin(ATX) has been reported as a direct biomarker for estimating the evaluation of liver fibrosis. But available data on ATX as a useful biomarker for the complications of liver cirrhosis(LC) are scant.AIM To assess the clinical usefulness of ATX for assessing the complications of LC.METHODS This multicenter, retrospective study was conducted at six locations in Japan. We include patients with LC, n = 400. The ATX level was evaluated separately in men and women because of its high level in female patients. To assess the clinical usefulness of ATX for the complications of LC, the area under the curve(AUC) of ATX assessing for the severe complications was analyzed in comparison with the model for end-stage liver disease score, albumin-bilirubin(ALBI) score, fibrosis-4 index, and aspartate aminotransferase-to-platelet ratio index.RESULTS The mean age was 68.4 ± 11.4 years, 240 patients(60.0%) were male. A total of 213(53.3%) and 187(46.8%) patients were compensated and decompensated,respectively. The numbers of patients with varix rupture, hepatic ascites, and hepatic encephalopathy were 35(8.8%), 131(32.8%), and 103(25.8%),respectively. The AUCs of ATX in men for hepatic encephalopathy, hepatic ascites, and varix ruptures were 0.853, 0.816, and 0.706, respectively. The AUCs of ATX in women for hepatic encephalopathy, hepatic ascites, and varix rupture were 0.759, 0.717, and 0.697, respectively. The AUCs of ATX in men were higher than those in women, as were all the other biomarkers used to detect encephalopathy and varix ruptures. However, for detecting ascites, the AUC of ALBI in men was more effective than using ATX.CONCLUSION ATX in men was more effective than any other biomarkers for detecting hepatic encephalopathy and varix ruptures.  相似文献   
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Background: Single inhaled corticosteroids and long-acting beta-agonists (ICS/LABA) are clinically effective and safe. However, if local oropharyngeal and laryngeal adverse effects (LOLAE) appear, adherence to the use of ICS is impaired. To minimize the development of adverse effects, it is essential to identify the underlying risk factors.Methods: The study included 481 asthmatic patients who were prescribed ICS/LABA for the first time in their life between January and September of 2010. Patients ranged in age from 14 to 86 years old and consisted of 281 never smokers and 200 smokers. All data were collected retrospectively by respirologists.Results: Seventy-three out of 481 patients suffered from one or more adverse effects, with 54 of these exhibiting LOLAE. Patients with LOLAE (51.4 ± 16.2 yrs) were significantly older than those without LOLAE (43.7 ± 15.9 yrs) (p = 0.0011) and were also prescribed a significantly higher dose of ICS. The pack-years of patients with LOLAE (2.1 ± 4.9) were significantly lowerthan those without LOLAE (6.0 ± 13.0) (p = 0.0087). The type of administered ICS was also significantly associated with a risk of developing LOLAE.Conclusions: Our survey indicated that a greater age, a higher dose of ICS, and the type of ICS were potential risk factors of LOLAE. The identified factors should be considered in a clinical setting in order to prevent the development of LOLAE and provide optimal treatment to patients.  相似文献   
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A clear understanding of the electron energy structure of TiO2(B)/anatase is needed to study the related catalytic reactions and design new composite photocatalysts. In this study, the electron energy structures of TiO2(B) and anatase were estimated by analyzing the energy-resolved distribution of electron traps measured by reversed double-beam photoacoustic spectroscopy. In the mixture of TiO2(B) and anatase, interfacial charge-transfer excitation from anatase to electron traps of TiO2(B) was suggested. By analyzing this for TiO2(B), the electron level with a relatively high density of states was found to be located ∼0.07 eV deeper than that for anatase. Furthermore, a similar electron energy structure was suggested for a composite photocatalyst having a mixed phase of TiO2(B) and anatase.

The electron energy structures of TiO2(B) and anatase were estimated by analyzing the energy-resolved distribution of electron traps.  相似文献   
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