498 research outputs found
Immunological Interactive Effects between Pollen Grains and Their Cytoplasmic Granules on Brown Norway Rats
International audienceBackgroundGrass pollen is one of the most important aeroallergen vectors in Europe. Under some meteorological factors, pollen grains can release pollen cytoplasmic granules (PCGs). PCGs induce allergic responses. Several studies have shown that during a period of thunderstorms the number of patients with asthma increases because of higher airborne concentrations of PCGs.ObjectiveThe aims of the study were to assess the allergenicity of interactive effects between pollen and PCGs and to compare it with allergenicity of Timothy grass pollen and PCGs in Brown Norway rats.MethodsRats were sensitized (day 0) and challenged (day 21) with pollen grains and/or PCGs. Four groups were studied: pollen-pollen (PP), PCGs-PCGs (GG), pollen-PCGs (PG), and PCGs-pollen (GP). Blood samples, bronchoalveolar lavage fluid, and bronchial lymph node were collected at day 25. IgE and IgG1 levels in sera were assessed by enzyme-linked immunosorbent assay. Alveolar cells, protein, and cytokine concentrations were quantified in bronchoalveolar lavage fluid. T-cell proliferation, in response to pollen or granules, was performed by lymph node assay.ResultsInteractive effects between pollen and PCGs increased IgE and IgG1 levels when compared with those of the negative control. These increases were lower than those of the PP group but similar to the levels obtained by the GG group. Whatever was used in the sensitization and/or challenge phase, PCGs increased lymphocyte and Rantes levels compared with those of the pollen group. The interactive effects increased IL-1α and IL-1β compared with those of the PP and GG groups.ConclusionsImmunologic interactive effects have been shown between pollen and PCGs. For humoral and cellular allergic responses, interactive effects between the 2 aeroallergenic sources used in this study seem to be influenced mainly by PCGs
Addendum to the CLOUD proposal
This report is the first of two addenda to the CLOUD proposal at CERN (physics/0104048), which aims to test experimentally the existence a link between cosmic rays and cloud formation, and to understand the microphysical mechanism. The document provides further details on the detector design, scientific motivation and experimental programme
CLOUD: an atmospheric research facility at CERN
This report is the second of two addenda to the CLOUD proposal at CERN (physics/0104048), which aims to test experimentally the existence a link between cosmic rays and cloud formation, and to understand the microphysical mechanism. The document places CLOUD in the framework of a CERN facility for atmospheric research, and provides further details on the particle beam requirements
Challenges for Allergy Diagnosis in Regions with Complex Pollen Exposures
Over the past few decades, significant scientific progress has influenced clinical allergy practice. The biological standardization of extracts was followed by the massive identification and characterization of new allergens and their progressive use as diagnostic tools including allergen micro arrays that facilitate the simultaneous testing of more than 100 allergen components. Specific diagnosis is the basis of allergy practice and is always aiming to select the best therapeutic or avoidance intervention. As a consequence, redundant or irrelevant information might be adding unnecessary cost and complexity to daily clinical practice. A rational use of the different diagnostic alternatives would allow a significant improvement in the diagnosis and treatment of allergic patients, especially for those residing in complex pollen exposure areas
Isolation, characterization and expression in Escherichia coli of a cDNA coding for a novel major wheat food allergen
A study of the link between cosmic rays and clouds with a cloud chamber at the CERN PS
Recent satellite data have revealed a surprising correlation between galactic cosmic ray (GCR) intensity and the fraction of the Earth covered by clouds. If this correlation were to be established by a causal mechanism, it could provide a crucial step in understanding the long-sought mechanism connecting solar and climate variability. The Earth's climate seems to be remarkably sensitive to solar activity, but variations of the Sun's electromagnetic radiation appear to be too small to account for the observed climate variability. However, since the GCR intensity is strongly modulated by the solar wind, a GCR-cloud link may provide a sufficient amplifying mechanism. Moreover if this connection were to be confirmed, it could have profound consequences for our understanding of the solar contributions to the current global warming. The CLOUD (Cosmics Leaving OUtdoor Droplets) project proposes to test experimentally the existence a link between cosmic rays and cloud formation, and to understand the microphysical mechanism. CLOUD plans to perform detailed laboratory measurements in a particle beam at CERN, where all the parameters can be precisely controlled and measured. The beam will pass through an expansion cloud chamber and a reactor chamber where the atmosphere is to be duplicated by moist air charged with selected aerosols and trace condensable vapours. An array of external detectors and mass spectrometers is used to analyse the physical and chemical characteristics of the aerosols and trace gases during beam exposure. Where beam effects are found, the experiment will seek to evaluate their significance in the atmosphere by incorporating them into aerosol and cloud models.Recent satellite data have revealed a surprising correlation between galactic cosmic ray (GCR) intensity and the fraction of the Earth covered by clouds. If this correlation were to be established by a causal mechanism, it could provide a crucial step in understanding the long-sought mechanism connecting solar and climate variability. The Earth's climate seems to be remarkably sensitive to solar activity, but variations of the Sun's electromagnetic radiation appear to be too small to account for the observed climate variability. However, since the GCR intensity is strongly modulated by the solar wind, a GCR-cloud link may provide a sufficient amplifying mechanism. Moreover if this connection were to be confirmed, it could have profound consequences for our understanding of the solar contributions to the current global warming. The CLOUD (Cosmics Leaving OUtdoor Droplets) project proposes to test experimentally the existence a link between cosmic rays and cloud formation, and to understand the microphysical mechanism. CLOUD plans to perform detailed laboratory measurements in a particle beam at CERN, where all the parameters can be precisely controlled and measured. The beam will pass through an expansion cloud chamber and a reactor chamber where the atmosphere is to be duplicated by moist air charged with selected aerosols and trace condensable vapours. An array of external detectors and mass spectrometers is used to analyse the physical and chemical characteristics of the aerosols and trace gases during beam exposure. Where beam effects are found, the experiment will seek to evaluate their significance in the atmosphere by incorporating them into aerosol and cloud models
Oxidation products of biogenic emissions contribute to nucleation of atmospheric particles
Atmospheric new-particle formation affects climate and is one of the least understood atmospheric aerosol processes. The complexity and variability of the atmosphere has hindered elucidation of the fundamental mechanism of new-particle formation from gaseous precursors. We show, in experiments performed with the CLOUD (Cosmics Leaving Outdoor Droplets) chamber at CERN, that sulfuric acid and oxidized organic vapors at atmospheric concentrations reproduce particle nucleation rates observed in the lower atmosphere. The experiments reveal a nucleation mechanism involving the formation of clusters containing sulfuric acid and oxidized organic molecules from the very first step. Inclusion of this mechanism in a global aerosol model yields a photochemically and biologically driven seasonal cycle of particle concentrations in the continental boundary layer, in good agreement with observations
Real-Life Study for the Diagnosis of House Dust Mite Allergy - The Value of Recombinant Allergen-Based IgE Serology
Background: Dermatophagoides pteronyssinus is one of the most important perennial allergen sources worldwide. Molecular diagnostics using the commercially available major allergens (Der p 1 and Der p 2) in combination with Der p 10 do not detect house dust mite (HDM) sensitization in a number of cases when used alone. The objective was to evaluate the IgE reactivity profiles of these patients using an experimental immunoassay biochip. Methods: Sera of HDM-allergic patients (positive skin prick test, CAP class 1 for allergen extract, and positive intranasal provocation) were tested for IgE antibodies against Der p 1, Der p 2, and Der p 10 by ImmunoCAP fluorescence enzyme immunoassay. Negatively tested sera were examined by an experimental chip containing 13 microarrayed HDM allergens. Results: Of 97 patients tested, 16 showed negative results to Der p 1, Der p 2, and Der p 10. MeDALL chip evaluation revealed 5 patients mono-sensitized to Der p 23, and 11 patients were negative for all HDM MeDALL chip components. Seven sera were available for further testing, and 3 of them showed IgE reactivity to dot-blotted nDer p 1, and 2 reacted with high-molecular weight components (>100 kDa) in nitrocellulose-blotted HDM extract when tested with 1251-labeled anti-IgE in a RAST-based assay. The HDM extract-specific IgE levels of the 11 patients were <3.9 kU/I. Conclusions: Recombinant allergen-based IgE serology is of great value when conventional IgE diagnostics fails. Der p 23 is an important HDM allergen, especially when major allergens are negative. Therefore, it would be desirable to have Der p 23 commercially available. Further research concerning the prevalence and clinical significance of different HDM allergens is needed. (C) 2016 S. Karger AG, Base
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