Caenorhabditis elegans: a model to monitor bacterial air quality

<p>Abstract</p> <p>Background</p> <p>Low environmental air quality is a significant cause of mortality and morbidity and this question is now emerging as a main concern of governmental authorities. Airborne pollution results from the combination of chemicals, fine particles, and micro-organisms quantitatively or qualitatively dangerous for health or for the environment. Increasing regulations and limitations for outdoor air quality have been decreed in regards to chemicals and particles contrary to micro-organisms. Indeed, pertinent and reliable tests to evaluate this biohazard are scarce. In this work, our purpose was to evaluate the <it>Caenorhaditis elegans </it>killing test, a model considered as an equivalent to the mouse acute toxicity test in pharmaceutical industry, in order to monitor air bacterial quality.</p> <p>Findings</p> <p>The present study investigates the bacterial population in dust clouds generated during crop ship loading in harbor installations (Rouen harbor, Normandy, France). With a biocollector, airborne bacteria were impacted onto the surface of agar medium. After incubation, a replicate of the colonies on a fresh agar medium was done using a velvet. All the replicated colonies were pooled creating the "Total Air Sample". Meanwhile, all the colonies on the original plate were isolated. Among which, five representative bacterial strains were chosen. The virulence of these representatives was compared to that of the "Total Air Sample" using the <it>Caenorhaditis elegans </it>killing test. The survival kinetic of nematodes fed with the "Total Air Sample" is consistent with the kinetics obtained using the five different representatives strains.</p> <p>Conclusions</p> <p>Bacterial air quality can now be monitored in a one shot test using the <it>Caenorhaditis elegans </it>killing test.</p

The human keratins: biology and pathology

The keratins are the typical intermediate filament proteins of epithelia, showing an outstanding degree of molecular diversity. Heteropolymeric filaments are formed by pairing of type I and type II molecules. In humans 54 functional keratin genes exist. They are expressed in highly specific patterns related to the epithelial type and stage of cellular differentiation. About half of all keratins—including numerous keratins characterized only recently—are restricted to the various compartments of hair follicles. As part of the epithelial cytoskeleton, keratins are important for the mechanical stability and integrity of epithelial cells and tissues. Moreover, some keratins also have regulatory functions and are involved in intracellular signaling pathways, e.g. protection from stress, wound healing, and apoptosis. Applying the new consensus nomenclature, this article summarizes, for all human keratins, their cell type and tissue distribution and their functional significance in relation to transgenic mouse models and human hereditary keratin diseases. Furthermore, since keratins also exhibit characteristic expression patterns in human tumors, several of them (notably K5, K7, K8/K18, K19, and K20) have great importance in immunohistochemical tumor diagnosis of carcinomas, in particular of unclear metastases and in precise classification and subtyping. Future research might open further fields of clinical application for this remarkable protein family

Regulation of Pseudomonas virulence and surface interactions by eukaryotic communication messengers.

International audienc

Eukaryotic benzodiazepine receptors ligands are sensed by Pseudomonas.

International audienc

Tabagisme et vapotage dans un CHRU en période de pandémie de covid-19 : Point de la campagne Hôpital et Campus Sans Tabac à Brest.

IntroductionIn the framework of a “tobacco-free hospital and campus” campaign, we conducted a study on the prevalence of smoking and vaping among a university hospital (CHRU) staff. The study took place in late 2020 (from 1 September to 15 December), and involved self-assessment of the impact of the covid-19 pandemic on smoking.Material and methodA cross-sectional study was carried out using an online questionnaire, which was distributed by email and QR code posting and included socio-professional details as well as data on participants’ smoking and vaping.ResultsThere were 782 responses, representing a participation rate of 13.5%. The sample included 73.3% women and 22.7% men; 28.9% nurses, 24.9% medical staff, 3.6% nursing assistants and 42.6% other professional categories. The overall smoking rate was 13%. Sixty-two (7.9%) participants vaped; 37 (5%) vaped exclusively, 25 (3.2%) combined smoking and vaping. Men smoked more than women: 23.7% vs. 9.4% (P < 0.01). Medical staff smoked and vaped less than other categories; 6.2% vs 14.8% (P < 0.01) and 4.1% vs 9.1% respectively (P = 0.02). Doctors were more often non-smokers: OR = 2.71 (95% CI: 1.14–6.46). Among smokers, 25% said they had increased their cigarette consumption during the covid-19 pandemic, frequently as a means of combating stress or fatigue.ConclusionThis study showed a lower smoking rate than in the literature, possibly due to the high participation of physicians. Ours were the initial estimates of vaping among hospital staff.IntroductionNous avons mené, dans le cadre d’une campagne "Hôpital et Campus Sans Tabac", une étude de prévalence du tabagisme et du vapotage auprès des personnels d’un CHRU.Matériel et méthodesÉtude transversale par questionnaire en ligne, au sujet du tabagisme et du vapotage, se déroulant entre le 01/01/2020 et le 15/12/2020.RésultatsSept cent quatre-vingt-deux questionnaires ont pu être analysés, soit un taux de participation de 13,5 %. L’échantillon comprenait 73,3 % de femmes et 22,7 % hommes; 28,9 % d’infirmiers, 24,9 % de personnels médical, 3,6 % d’aides-soignants et 42,6 % d’autres catégories professionnelles. Le taux de tabagisme était de 13 %. Soixante-deux (7,9 %) des participants vapotaient ; 37 (5 %) vapotaient exclusivement, 25 (3,2 %) associaient tabagisme et vapotage. Les hommes fumaient plus que les femmes : 23,7 % vs 9,4 % (p < 0,01). Les personnels médicaux fumaient et vapotaient moins que les autres catégories ; respectivement 6,2 % vs 14,8 % (p < 0,01) et 4,1 % vs 9,1 % (p = 0,02). Parmi les fumeurs, 25 % déclaraient avoir augmenté leur consommation de cigarettes pendant la pandémie de covid-19, particulièrement afin de lutter contre le stress ou la fatigue.ConclusionCette étude montrait une faible prévalence de tabagisme. Il s’agissait des premières estimations du vapotage parmi du personnel hospitalier