20 research outputs found

    Threat of allergenic airborne grass pollen in Szczecin, NW Poland: the dynamics of pollen seasons, effect of meteorological variables and air pollution

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    The dynamics of Poaceae pollen season, in particularly that of the Secale genus, in Szczecin (western Poland) 2004–2008 was analysed to establish a relationship between the meteorological variables, air pollution and the pollen count of the taxa studied. Consecutive phases during the pollen season were defined for each taxon (1, 2.5, 5, 25, 50, 75, 95, 97.5, 99% of annual total), and duration of the season was determined using the 98% method. On the basis of this analysis, the temporary differences in the dynamics of the seasons were most evident for Secale in 2005 and 2006 with the longest main pollen season (90% total pollen). The pollen season of Poaceae started the earliest in 2007, when thermal conditions were the most favourable. Correlation analysis with meteorological factors demonstrated that the relative humidity, mean and maximum air temperature, and rainfall were the factors influencing the average daily pollen concentrations in the atmosphere; also, the presence of air pollutants such as ozone, PM10 and SO2 was statistically related to the pollen count in the air. However, multiple regression models explained little part of the total variance. Atmospheric pollution induces aggravation of symptoms of grass pollen allergy

    Exposure to extreme heat and precipitation events associated with increased risk of hospitalization for asthma in Maryland, U.S.A.

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    Several studies have investigated the association between asthma exacerbations and exposures to ambient temperature and precipitation. However, limited data exists regarding how extreme events, projected to grow in frequency, intensity, and duration in the future in response to our changing climate, will impact the risk of hospitalization for asthma. The objective of our study was to quantify the association between frequency of extreme heat and precipitation events and increased risk of hospitalization for asthma in Maryland between 2000 and 2012. We used a time-stratified case-crossover design to examine the association between exposure to extreme heat and precipitation events and risk of hospitalization for asthma (ICD-9 code 493, n = 115,923). Occurrence of extreme heat events in Maryland increased the risk of same day hospitalization for asthma (lag 0) by 3 % (Odds Ratio (OR): 1.03, 95 % Confidence Interval (CI): 1.00, 1.07), with a considerably higher risk observed for extreme heat events that occur during summer months (OR: 1.23, 95 % CI: 1.15, 1.33). Likewise, summertime extreme precipitation events increased the risk of hospitalization for asthma by 11 % in Maryland (OR: 1.11, 95 % CI: 1.06, 1.17). Across age groups, increase in risk for asthma hospitalization from exposure to extreme heat event during the summer months was most pronounced among youth and adults, while those related to extreme precipitation event was highest among ≤4 year olds. Exposure to extreme heat and extreme precipitation events, particularly during summertime, is associated with increased risk of hospitalization for asthma in Maryland. Our results suggest that projected increases in frequency of extreme heat and precipitation event will have significant impact on public health.https://doi.org/10.1186/s12940-016-0142-

    The trypsin-induced leucostasis which leads to emphysema in the hamster is not due to contaminating endotoxins

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    International audienceIntravenous injection of trypsin in the rat induces early lung leucostasis and emphysema of delayed onset. This report confirms that this emphysema is not rat-specific and that the leucostasis is not related to the presence of contaminating endotoxin in the trypsin. In hamsters (n=37), leucostasis did not occur when they were injected with heat-treated trypsin, but numerous granulocytes were sequestered in the vessels of hamsters receiving a fresh solution of trypsin. In these hamsters, the number of granulocytes harvested by lavage increased significantly (1-87 x 10⁶ per ml, .P<0-001) compared with hamsters injected with either heat-denatured trypsin (0-89) or saline (0-86), or compared with controls (0-86). Emphysema was inconstantly observed in hamsters 6 or 12 weeks after injection with trypsin for l h. It was frequently (17/20) present and always (20/20) well developed (intercept+180 per cent) in the 2-h perfused hamsters whose lungs were abnormally heterogeneous (index+100 per cent) relative to the seven controls and to the nine saline-injected hamsters. The efficiency of trypsin in triggering emphysema (percentage of hamsters having abnormal values of intercept) was dependent on the time of perfusion. This form of experimental emphysema is thus considered to be due to an endotoxin-independent leucostasis

    Purification de la vitellogénine de trois espèces de poissons truite arc en ciel (Oncorhynchus mykiss), goujon (Gobio gobio) et chevaine (Leuciscus cephalus)

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    International audienceA two step purification protocol was developed to purify rainbow trout (Oncorhynchus mykiss) Vitellogenin (Vtg) and was successfully applied to Vtg of chub (Leuciscus cephalus) and gudgeon (Gobio gobio). Capture and intermediate purification were performed by anion exchange chromatography on a Resource Q column and a polishing step was performed by gel permeation chromatography on Superdex 200 column. This method is a rapid two step purification procedure that gave a pure solution of Vtg as assessed by silver staining electrophoresis and immunochemical characterisation.L'induction et la purification de la vitellogénine chez la truite, le chevaine et le goujon a été réalisée. Le but de ces expériences est de disposer de la protéine purifiée utilisable dans la méthode ELISA pour quantifier la vitellogénine présente dans les échantillons à partir d'une calibration spécifique pour chaque espèce. Le travail réalisé a permis la mise au point d'une méthode de purification à deux étape chromatographique

    Towards an identification of water soluble and water-insoluble allergens of pollen cytoplasmic granules

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    Old tunnels are generally supported by masonry structure. Nowadays, these constructions present many instability problems (cracks, collapses, convergence, etc.) due to aging phenomena on both blocks and mortars. After the analysis of blocks mechanical behaviour over time [Idris, J., Verdel, T., Al-Heib, M., 2008a. Numerical modelling and mechanical behaviour analysis of ancient tunnel masonry structures. Tunnelling and Underground Space Technology 23, 251-263.], we try in this paper to simulate the evolution of masonry joints mechanical behaviour in built tunnels and to quantify the influence of their mechanical proprieties on the tunnel behaviour by the help of the experimental design method and distinct elements numerical modellin

    Nanoparticle reactivity toward dithiothreitol

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    Hazard determination of nanoparticles (NP) is challenging and should be based on a predictive and pragmatic tier approach. The biological effects of NP appear to be related not only to surface/size but also to their ability to generate free radicals/oxidants. We propose that the measurement of this property by acellular assays could be helpful for NP toxicity screening. This study investigated the effect of dispersing conditions on the oxidative capacity of a small selection of carbonaceous NP toward dithiothreitol (DTT). Increasing surfactant concentration decreased the DTT reactivity on these studied particles. Afterward, a panel of NP were studied under constant conditions. Classification of the NP panel based on their DTT reactivity was found to be dependent on the metric used (mass or surface) but not on the surfactant type. The DTT assay may be useful for an initial evaluation of the hazardousness of manufactured or unintentionally produced NP. However, the predictive potential of such a test towards biological effects still needs to be evaluated. [Authors]]]> Dithiothreitol ; Nanoparticles ; Surface-Active Agents ; Soot eng oai:serval.unil.ch:BIB_1E9534488A45 2022-02-19T02:15:39Z <oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"> https://serval.unil.ch/notice/serval:BIB_1E9534488A45 Role of defensins and cathelicidin LL37 in auto-immune and auto-inflammatory diseases. info:doi:10.2174/138920112802273155 info:eu-repo/semantics/altIdentifier/doi/10.2174/138920112802273155 info:eu-repo/semantics/altIdentifier/pmid/22250708 Frasca, L. Lande, R. info:eu-repo/semantics/review article 2012 Current Pharmaceutical Biotechnology, vol. 13, no. 10, pp. 1882-1897 info:eu-repo/semantics/altIdentifier/eissn/1873-4316 urn:issn:1389-2010 <![CDATA[Defensins and cathelicidins are anti-microbial peptides (AMPs) that act as natural antibiotics and are part of the innate immune defence in many species. We consider human defensins and LL37, the only human member of the cathelicidin family. In particular, we refer to the human alpha-defensins called human neutrophil peptides (HNP1 through 4), which are produced by neutrophils, HD5 and HD6, mainly expressed in Paneth cells of intestine, the human beta-defensins HBD1, HBD2 and HBD3, synthesized by epithelial cells and LL37, which is located in granulocytes, but is also produced by epithelial cells of the skin, lungs, and gut. In the last years, the study of AMPs activity and regulation has allowed to understand the important role of these peptides not only in the innate defence mechanisms against bacteria, viruses, fungi, but also in the regulation of immune cell activation and migration. Complementary studies have disclosed a role for AMPs in modulating many physiological processes that involve non-immune cells, such as activation of wound healing, angiogenesis, cartilage remodeling. Due to the pleiotropic tasks of these peptides, many of them are now being discovered to contribute to immune pathology of chronic diseases that affect skin, gut, joints; this is supported by many examples of immune-mediated pathologies in which their expression is disregulated. In this article we review the current literature that suggests a role for human defensins and LL37 in pathogenic mechanisms of several chronic diseases that are considered of auto-immune or auto-inflammatory origin
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