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Occupational exposure to ultrafine particles and lung cancer in a population exposed to asbestos
No full textInternational audienceBackground: Ultrafine particles are present in ever greater quantities in the workplace and only one epidemiological study to date has found an association with the occurrence of lung cancer.Objective: To investigate the effect of occupational exposure to ultrafine particles on the risk of lung cancer.Methods: The ARDCO is a surveillance program involving retiree workers who had been exposed to asbestos during their working life. Exposure to ultrafine particles over the complete lifetime occupational history was assessed using the French job exposure matrix MATPUF. Cox proportional hazard models were used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CI).Results: There was no association between exposure to ultrafine particles and lung cancer after adjustment for smoking and exposure to asbestos and crystalline silica.Conclusion: The findings do not indicate increased risks of lung cancer for UFP after adjustment for level of exposure to asbestos, crystalline silica, and smoking status.Clinical trial number: Not applicable
Technosols made of urban wastes are suitable habitats for flora and soil macrofauna
No full textInternational audienceCities are increasingly recognized as specific ecosystems, in which green infrastructures, gardens, parks… can offer new habitats to flora and fauna. Cities also have a limited ability to recycle waste, which could be improved by transforming certain construction waste into Technosols. Here, we show that Technosols made of “fine earth”, excavated from deep soil horizons and usually deposited in landfills by the building sector, can promote plant growth, plant diversity and soil macrofauna. A four-year follow-up showed diversity and abundance levels comparable to temperate meadows. It also suggests a strong potential in terms of carbon storage. This solution could thus simultaneously supply a resource for local green spaces, reduce construction waste in landfills, lessen topsoil removal from neighboring environments, helping cities to take their part in climate change mitigation and biodiversity conservation efforts
<i>N</i> -Acetylcysteine Prevents the Deleterious Effect of Tumor Necrosis Factor-α on Calcium Transients and Contraction in Adult Rat Cardiomyocytes
No full textInternational audienceackground: The negative effect of tumor necrosis factor-alpha (TNF-alpha) on heart contraction, which is mediated by sphingosine, is a major component in heart failure. Because the cellular level of glutathione may limit sphingosine production via the inhibition of the Mg-dependent neutral sphingomyelinase (N-SMase), we hypothesized that cardiac glutathione status might determine the negative contractile response to TNF-alpha.Methods and results: We examined the effects of TNF-alpha in isolated cardiomyocytes obtained from control rats or rats that were given the glutathione precursor N-acetylcysteine (NAC, 100 mg IP per animal). In cardiomyocytes obtained from control rats, 25 ng/mL TNF-alpha increased reactive oxygen species generation and N-SMase activity (500% and 34% over basal, respectively) and decreased the amplitude of [Ca(2+)](i) in response to electrical stimulation (22% below basal). NAC treatment increased cardiac glutathione content by 42%. In cardiomyocytes obtained from NAC-treated rats, 25 ng/mL TNF-alpha had no effect on reactive oxygen species production or N-SMase activity but increased the amplitude of [Ca(2+)](i) transients and contraction in response to electrical stimulation by 40% to 50% over basal after 20 minutes. This was associated with a hastened relaxation (20% reduction in t(1/2) compared with basal) and an increased phosphorylation of both Ser(16)- and Thr(17)-phospholamban residues (260% and 115% of maximal isoproterenol effect, respectively).Conclusions: It is concluded that cardiac glutathione status, by controlling N-SMase activation, determines the severity of the adverse effects of TNF-alpha on heart contraction. Glutathione supplementation may therefore provide therapeutic benefits for vulnerable hearts
Linear isometries on the annulus: description and spectral properties
No full textInternational audienceWe give a complete characterisation of the linear isometries of Hol(Ω), where Ω is the half-plane, the complex plane or an annulus centered at 0 and symmetric to the unit circle. Moreover, we introduce new techniques to describe the holomorphic maps on the annulus that preserve the unit circle, and we finish by proving results about the spectra of the linear isometries on the annulus
Flight initiation distance differs among eumelanin‐based color morphs in feral pigeons
No full textInternational audienceOrganisms facing anthropogenic activities usually exhibit phenotypic responses assumed to enhance coping with disturbance. These responses include a decreasing degree of reaction toward potentially risky situations (“behavioral tolerance”) with increasing disturbance. Though melanin is associated with many phenotypic traits, including pigmentation and behavior, the potential relationship between behavioral tolerance and melanin has never been explored. Such relationship may potentially result from either direct association between melanin and behavior (e.g., genetic correlation) or indirectly through a coloration‐dependent behavior‐modulating factor (e.g., differential predation or human preferences in cities toward color morphs). Feral pigeons ( Columba livia ) represent an ideal biological system to test for these hypotheses, due to their presence in cities worldwide, their considerable variation in eumelanin‐based coloration, ranging from white to black plumage, and their close proximity to humans. We measured Flight Initiation Distance (FID, classically used for behavioral tolerance assessment) of feral pigeons of 4 different eumelanin‐based color morphs in sites differing in their urbanization rate and pedestrian traffic within the restricted scale of a city center (Paris). Urbanization rate and pedestrian traffic had no effect on FID, maybe because of the small spatial scale considered. FID varied with eumelanin‐based coloration: white pigeons had lower FID (104.6 cm; i.e., higher behavioral tolerance) than darker morphs (232.3 cm for Blue bar, 184.4 cm for T‐pattern & Checker, and 181.8 cm for Spread color morphs). Though the exact underlying causes remain to be identified, we propose different possible mechanisms for this relationship that remain to be investigated in future work.Les organismes confrontés aux activités anthropiques présentent généralement des réponses phénotypiques considérées comme facilitant leur tolérance aux perturbations. Parmi ces réponses figure un degré décroissant de réaction face à des situations potentiellement risquées (« tolérance comportementale ») lorsque les perturbations augmentent. Bien que la mélanine soit associée à des nombreux traits phénotypiques, y compris la pigmentation et le comportement, la relation potentielle entre la tolérance comportementale et la mélanine n'a jamais été explorée. Une telle relation pourrait résulter soit d'une association directe entre la mélanine et le comportement (par exemple, du fait de corrélations génétiques) ou par l'intermédiaire d'un facteur dépendant de la coloration et modulant le comportement (par exemple, une prédation ou une préférence humaine différentielle envers les morphes de couleur). Les pigeons représentent un système biologique idéal pour tester ces hypothèses, du fait de leur présence dans les villes autour du globe et leur considérable variation dans la coloration eumélanique de leur plumage, s'étendant du blanc au noir. Nous avons mesuré la Distance d'Initiation de Fuite (FID, classiquement utilisée pour estimer la tolérance comportementale) de pigeons bisets féraux de différents morphes mélaniques, dans des sites différant par leur degré d’urbanisation et le trafic piéton à l'échelle restreinte du centre d'une ville (Paris). Le degré d’urbanisation et le trafic piéton n'avaient pas d'effet sur la FID (peut‐être du fait de la petite échelle spatiale considérée). La FID variait avec la coloration mélanique: les pigeons blancs avaient une FID plus faible (donc une tolérance comportementale plus élevée) que les morphes sombres. Bien que la cause sous‐jacente précise reste à découvrir, nous proposons différents mécanismes possibles pour cette relation, qui restent à explorer dans des travaux futurs
L'injonction d'office
No full textInternational audienceDernière pierre à l'édifice de l'injonction en contentieux administrati
Fluid management in adult patients undergoing venoarterial extracorporeal membrane oxygenation: A scoping review
No full textInternational audienc
A common form of dominant human IFNAR1 deficiency impairs IFN-α and -ω but not IFN-β-dependent immunity
No full textInternational audienceAutosomal recessive deficiency of the IFNAR1 or IFNAR2 chain of the human type I IFN receptor abolishes cellular responses to IFN-α, -β, and -ω, underlies severe viral diseases, and is globally very rare, except for IFNAR1 and IFNAR2 deficiency in Western Polynesia and the Arctic, respectively. We report 11 human IFNAR1 alleles, the products of which impair but do not abolish responses to IFN-α and -ω without affecting responses to IFN-β. Ten of these alleles are rare in all populations studied, but the remaining allele (P335del) is common in Southern China (minor allele frequency ≈2%). Cells heterozygous for these variants display a dominant phenotype in vitro with impaired responses to IFN-α and -ω, but not -β, and viral susceptibility. Negative dominance, rather than haploinsufficiency, accounts for this dominance. Patients heterozygous for these variants are prone to viral diseases, attesting to both the dominance of these variants clinically and the importance of IFN-α and -ω for protective immunity against some viruses
Role of Heterogeneous Reactions in the Atmospheric Oxidizing Capacity in Island Environments
No full textInternational audienceThe source of nitrous acid (HONO) and its importance in island or marine environments are poorly understood. Herein, based on comprehensive field measurements at a hilltop on Corsica Island, we find an inverse diel variation of HONO with higher concentrations during daytime. Night-time HONO budget analysis indicates significant HONO formation during air mass transport along the hillside. In the daytime, although photosensitized NO2 uptake on the ground and NO + OH make considerable contributions (26% and 5%, respectively), a large part of HONO formation (67%, 320 pptv h–1) still cannot be explained with state-of-the-art parametrization. Nevertheless, photosensitized heterogeneous NO2 reactions are likely to account for the missing source, due to underestimation of the source by typical parametrizations at low NO2 levels. Furthermore, we demonstrate a significant role of HONO formation as a OH primary source at this island site, with a OH production rate exceeding one-fourth of that of O3 photolysis. Our findings underscore a potential role of heterogeneous surface reactions in the oxidizing capacity of the island environments