36 research outputs found

    Management based on exhaled nitric oxidelevels adjusted for atopy reduces asthma exacerbations in children : A dual centre randomised controlled trial

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    While several randomised control trials (RCTs) have evaluated the use of fractional exhaled nitric oxide (FeNO) to improve asthma outcomes, none used FeNO cut-offs adjusted for atopy, a determinant of FeNO levels. In a dual centre RCT, we assessed whether a treatment strategy based on FeNO levels, adjusted for atopy, reduces asthma exacerbations compared with the symptoms-based management (controls). Children with asthma from hospital clinics of two hospitals were randomly allocated to receive an a-priori determined treatment hierarchy based on symptoms or FeNO levels. There was a 2-week run-in period and they were then reviewed ten times over 12-months. The primary outcome was the number of children with exacerbations over 12-months. Sixty-three children were randomised (FeNO=31, controls=32); 55 (86%) completed the study. Although we did achieve our planned sample size, significantly fewer children in the FeNO group (6 of 27) had an asthma exacerbation compared to controls (15 of 28), p=0.021; number to treat for benefit=4 (95%CI 3-24). There was no difference between groups for any secondary outcomes (quality of life, symptoms, FEV1). The final daily inhaled corticosteroids (ICS) dose was significantly (p=0.037) higher in the FeNO group (median 400µg, IQR 250-600) compared to the controls (200, IQR100-400). Taking atopy into account when using FeNO to tailor asthma medications is likely beneficial in reducing the number of children with severe exacerbations at the expense of increased ICS use. However, the strategy is unlikely beneficial for improving asthma control. A larger study is required to confirm or refute our findings

    Antibodies against endogenous retroviruses promote lung cancer immunotherapy

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    B cells are frequently found in the margins of solid tumours as organized follicles in ectopic lymphoid organs called tertiary lymphoid structures (TLS)1,2. Although TLS have been found to correlate with improved patient survival and response to immune checkpoint blockade (ICB), the underlying mechanisms of this association remain elusive1,2. Here we investigate lung-resident B cell responses in patients from the TRACERx 421 (Tracking Non-Small-Cell Lung Cancer Evolution Through Therapy) and other lung cancer cohorts, and in a recently established immunogenic mouse model for lung adenocarcinoma3. We find that both human and mouse lung adenocarcinomas elicit local germinal centre responses and tumour-binding antibodies, and further identify endogenous retrovirus (ERV) envelope glycoproteins as a dominant anti-tumour antibody target. ERV-targeting B cell responses are amplified by ICB in both humans and mice, and by targeted inhibition of KRAS(G12C) in the mouse model. ERV-reactive antibodies exert anti-tumour activity that extends survival in the mouse model, and ERV expression predicts the outcome of ICB in human lung adenocarcinoma. Finally, we find that effective immunotherapy in the mouse model requires CXCL13-dependent TLS formation. Conversely, therapeutic CXCL13 treatment potentiates anti-tumour immunity and synergizes with ICB. Our findings provide a possible mechanistic basis for the association of TLS with immunotherapy response

    An XPS study of the influence of chemisorbed oxygen on the adsorption of ethylene and water vapour by Cu (110) and Cu (111) surfaces

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    The adsorption of ethylene and water vapour on Cu (110) and Cu (111) surfaces has been studied by x-ray photoelectron spectroscopy in the temperature range 80 K to 373 K. Adsorption at 80 K is molecular in each case and desorption complete at ~ 160 K. There is little or no evidence for interaction after long exposure to ethylene up to 373 K. Prexposure of both Cu (110) and Cu (111) surfaces to oxygen activates both the C—H bond in ethylene and the O—H bond in water. The asymmetry in the O (1s) binding energy is indicative of surface hydroxylation and by curve-fitting the O (1s) spectra, and comparing with the C (1s) spectra, the stoichiometry of the adsorption process is shown to involve the generation in a 1 :1 ratio of C2H3(a) and OH(a) species at 373 K. It is suggested that the process occurs by a dual-site mechanism involving both Cu and 0δ— (a) species. At low temperature (150 K) we have evidence for a hydrogen-bonded precursor state. These results are analogous to other studies (HCI, H2S) where surface hydroxylation is followed by the chemisorptive replacement of chemisorbed oxygen by chlorine and sulphur

    Special issue on structural identification and monitoring with dynamic data

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    Preface. Special issue S1 April 2015Dr. Ching-Tai Ng, Prof. Siu-Kui A

    RE0.6Zr0.4-xYxO2 (RE = Ce, Pr; x = 0, 0.05) solid solutions: an investigation on defective structure, oxygen mobility, oxygen storage capacity, and redox properties

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    We have examined the crystal structures, surface textures, oxygen mobility, oxygen storage capacity, and redox behaviors of RE0.6Zr 0.4-xYxO2 (RE=Ce, Pr; x=0, 0.05) solid solutions. According to the results of X-ray diffraction (XRD) studies, there are two cubic phases (Ce0.75Zr0.25O2, major; ZrO1.87, minor) in Ce0.6Zr0.4O2 (denoted as CZ hereafter) and Ce0.6Zr0.35Y 0.05O2 (CZY), but only one cubic phase in Pr 0.60Zr0.40O2 (PZ) and Pr0.60Zr 0.35Y0.05O2 (PZY). These nanosized materials are porous and have large surface areas. As revealed by the Ce 3d and Pr 3d results of X-ray photoelectron spectroscopic (XPS) investigations, the doping of Y3+ ions into the CZ and PZ lattices resulted in an increase in concentration of oxygen vacancies and Ce3+ and Pr4+ ions. The results of H2 (or CO)-O2 titration and temperature-programmed reduction (TPR)-reoxidation experiments indicate the presence of a reversible redox behavior of Ce4+/Ce3+ in CZY and Pr4+/Pr3+ in PZY. The results of 18O/16O exchange studies show that, with the presence of oxygen vacancies, the lattice O2- mobility on/in CZY and PZY enhanced. Based on such outcomes, we conclude that, by incorporating Y 3+ ions into CZ and PZ, one can enhance (i) lattice oxygen mobility, (ii) Ce3+ and Pr4+ concentrations, and (iii) oxygen uptake capacity. We observed that PZY is superior to CZY in redox behavior, oxygen mobility, and oxygen storage capacity. © 2003 Elsevier B.V. All rights reserved

    Activation of oxygen at metal surfaces

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    Synthesis of plait-like carbon nanocoils in ultrahigh yield, and their microwave absorption properties

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    Over Ni nanoparticles generated by means of a combined sol-gel/reduction method, crystalline plait-like carbon nanocoils (CNCs) were synthesized in acetylene pyrolysis at 415 degrees C. The field-emission scanning electron microscope (FE-SEM) and high-resolution transmission electron microscope (HR-TEM) images reveal that there are often two CNCs in opposite handedness fused in one nanoplait. By optimization of reaction parameters, maximum purities and yields of plait-like CNCs and single CNCs were 99.35 wt % and 99.53 wt %, and ca. 18759.8% and 21269.6%, respectively. The pyrolysis of acetylene was carried out at 415 degrees C, and no dilute gas such as argon and nitrogen was needed. Thus, we have provided a simple, low-cost, and environmentally friendly approach for the mass production of CNCs with ultrahigh purity. The microwave absorption properties of the as-prepared plait-like CNCs and single CNCs were examined systematically. The results demonstrated that the as-prepared plait-like CNCs exhibit good microwave absorbing ability. The effects of the temperatures for acetylene pyrolysis and for NiO powder reduction in the CNCs synthesis on the morphology, yield, and microwave absorption properties of carbon products were also investigated

    Pd-, Pt-, Rh-loaded Ce0.6Zr0.35Y0.05O2 solid solution three-way catalysts: An investigation on performance and redox properties

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    The redox behaviors, oxygen mobilities, and oxygen storage capacities of Ce0.6Zr0.4O2 (CZ), Ce0.6Zr0.35Y0.05O2 (CZY), and 0.5 wt% M/CZY (M = Pd, Pt, Rh) as well as the three-way catalytic performance of the noble metal-loaded CZY materials have been investigated. It is observed that at a space velocity of 60,000 h-1 and in an atmosphere close to the theoretical air-to-fuel ratio (i.e., 14.6), the CZY-supported precious metal catalysts showed good three-way catalytic activity. X-ray diffraction investigations revealed that there are two phases (cubic Ce0.75Zr0.25O2, major; cubic ZrO1.87, minor) in CZ, CZY, and 0.5 wt% M/CZY. These materials are porous and large in surface area. According to the results of Ce 3d X-ray photoelectron spectroscopic studies, the doping of Y3+ ions into the CZ lattice would cause the concentrations of oxygen vacancies and Ce3+ ions to increase. The results of H2(or CO)-O2 titration and temperature-programmed reduction-reoxidation experiments indicate the presence of a reversible redox behavior of Ce4+/Ce3+ couples. The results of 18O/16O isotope exchange studies show that in the presence of oxygen vacancies and noble metals, the mobility of lattice oxygen on/in CZY is promoted. Based on the above outcomes, we suggest that by incorporating Y3+ ions into CZ and loading Pd, Pt, or Rh on CZY, one can enhance (i) lattice oxygen mobility, (ii) Ce3+ ion concentration, and (iii) oxygen uptake capacity of the CZY solid solution, generating a class of materials suitable for the catalytic conversion of automotive exhaust. © 2002 Elsevier Science (USA)
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