Effect of Oils Categories on the Distribution of Polycyclic Aromatic Hydrocarbons and Derivatives in the Environment

Context and objective: The Migr’Hycar research project was initiated to provide decisional tools for risks connected to oil spill drifts in continental waters. This paper focuses on the distribution of polycyclic aromatic hydrocarbons (PAHs) from oils in water, air and oil slicks. Material and methods: Six petroleum oils covering a representative range of commercially available products were tested. Dynamic tests at laboratory scale were performed to study 41 PAHs and derivates, among them 16 EPA priority pollutants. Water soluble fraction protocol, stir bar sorptive extraction (SBSE) and high performance gas chromatography mass spectrometry (HPGC-MS) was used. Limit of quantification were lower than 1 ng.L-1 for each compounds. Results: A large variation in composition of the water soluble fraction depending on oil type and mixing time has been highlighted. Results have shown that evaporation is the primary mechanism of PAHs loss from spilled oil. The subsequent fate of hydrocarbons deposited in surface water is further influenced by volatilisation behaviour because of possible slick loss to the atmosphere. The water soluble fraction remains very low and is dominated by low molecular weight PAHS (e.g. naphthalenes)

Dynamic Behavior of Polycyclic Aromatic Hydrocarbons and Their Derivatives after Oils Spill in Water

Within the framework of Migr’Hycar research project, the fate of oil spill was studied with the aim to characterize their physical-chemical behaviour. For this purpose, seven petroleum oils com- mercially available were tested and the distributions of the water soluble components were deter- mined according to two experimental devices; laboratory conditions and pilot conditions in Pollu- drome. In the dissolved fraction, 41 polycyclic aromatic hydrocarbons and their derivates were quantified, among them are 16 EPA priority pollutants. A coupling of the stir bar sorptive extrac-tion method and high performance gas chromatography mass spectrometry were used. Analyses showed that naphthalenes series constitute the major part of the water soluble fraction from fresh oils. In fact, light and heavy molecules have different contributions to solubilization kinetics. From the results, a linear correlation was established between the density of oils and the times of max-imum solubilization. Moreover, the effect of 10% ethanol in gasoline was observed on the profile of solubilized PAHs in water. Kinetic patterns obtained with Polludrome showed the influence of surface water/oil ratio (WOR) on the volatilization process. Compared to laboratory conditions, the dynamic conditions of Polludrome led to an enhanced evaporation process, thus shifting the solubility peak

Soluble factors regulated by epithelial-mesenchymal transition mediate tumour angiogenesis and myeloid cell recruitment.

peer reviewedEpithelial-to-mesenchymal transition (EMT) programs provide cancer cells with invasive and survival capacities that might favor metastatic dissemination. Whilst signaling cascades triggering EMT have been extensively studied, the impact of EMT on the crosstalk between tumor cells and the tumor microenvironment remains elusive. We aimed to identify EMT-regulated soluble factors that facilitate the recruitment of host cells in the tumor. Our findings indicate that EMT phenotypes relate to the induction of a panel of secreted mediators, namely IL-8, IL-6, sICAM-1, PAI-1 and GM-CSF, and implicate the EMT-transcription factor Snail as a regulator of this process. We further show that EMT-derived soluble factors are pro-angiogenic in vivo (in the mouse ear sponge assay), ex vivo (in the rat aortic ring assay) and in vitro (in a chemotaxis assay). Additionally, conditioned medium from EMT-positive cells stimulates the recruitment of myeloid cells. In a bank of 40 triple-negative breast cancers, tumors presenting features of EMT were significantly more angiogenic and infiltrated by a higher quantity of myeloid cells compared to tumors with little or no EMT. Taken together, our results show that EMT programs trigger the expression of soluble mediators in cancer cells that stimulate angiogenesis and recruit myeloid cells in vivo, which might in turn favor cancer spread

Effects of a short residential thermal spa program to prevent work-related stress/burnout on stress biomarkers: The thermstress proof of concept study

Objective Work-related stress is a public health issue. Stress has multiple physical and psychological consequences, the most serious of which are increased mortality and cardiovascular morbidity. The ThermStress protocol was designed to offer a short residential thermal spa program for work-related stress prevention that is compatible with a professional context. Methods Participants will be 56 male and female workers aged 18 years or above. All participants will undergo a 6-day residential spa program comprising psychological intervention, physical activity, thermal spa treatment, health education, eating disorder therapy and a follow-up. On six occasions, participants’ heart rate variability, cardiac remodelling and function, electrodermal activity, blood markers, anthropometry and body composition, psychology and quality of life will be measured using questionnaires and bone parameters. Results This study protocol reports the planned and ongoing research for this intervention. Discussion The ThermStress protocol has been approved by an institutional ethics committee (ANSM: 2016 A02082 49). It is expected that this proof of concept study will highlight the effect of a short-term specific residential thermal spa program on the prevention of occupational burnout and work-related stress. The findings will be disseminated at several research conferences and in published articles in peer-reviewed journals. Trial Registration: ClinicalTrials.gov (NCT 03536624, 24/05/2018

Tye7 regulates yeast Ty1 retrotransposon sense and antisense transcription in response to adenylic nucleotides stress

Transposable elements play a fundamental role in genome evolution. It is proposed that their mobility, activated under stress, induces mutations that could confer advantages to the host organism. Transcription of the Ty1 LTR-retrotransposon of Saccharomyces cerevisiae is activated in response to a severe deficiency in adenylic nucleotides. Here, we show that Ty2 and Ty3 are also stimulated under these stress conditions, revealing the simultaneous activation of three active Ty retrotransposon families. We demonstrate that Ty1 activation in response to adenylic nucleotide depletion requires the DNA-binding transcription factor Tye7. Ty1 is transcribed in both sense and antisense directions. We identify three Tye7 potential binding sites in the region of Ty1 DNA sequence where antisense transcription starts. We show that Tye7 binds to Ty1 DNA and regulates Ty1 antisense transcription. Altogether, our data suggest that, in response to adenylic nucleotide reduction, TYE7 is induced and activates Ty1 mRNA transcription, possibly by controlling Ty1 antisense transcription. We also provide the first evidence that Ty1 antisense transcription can be regulated by environmental stress conditions, pointing to a new level of control of Ty1 activity by stress, as Ty1 antisense RNAs play an important role in regulating Ty1 mobility at both the transcriptional and post-transcriptional stages

Validating intravascular imaging with serial optical coherence tomography and confocal fluorescence microscopy

Atherosclerotic cardiovascular diseases are characterized by the formation of a plaque in the arterial wall. Intravascular ultrasound (IVUS) provides high-resolution images allowing delineation of atherosclerotic plaques. When combined with near infrared fluorescence (NIRF), the plaque can also be studied at a molecular level with a large variety of biomarkers. In this work, we present a system enabling automated volumetric histology imaging of excised aortas that can spatially correlate results with combined IVUS/NIRF imaging of lipid-rich atheroma in cholesterol-fed rabbits. Pullbacks in the rabbit aortas were performed with a dual modality IVUS/NIRF catheter developed by our group. Ex vivo three-dimensional (3D) histology was performed combining optical coherence tomography (OCT) and confocal fluorescence microscopy, providing high-resolution anatomical and molecular information, respectively, to validate in vivo findings. The microscope was combined with a serial slicer allowing for the imaging of the whole vessel automatically. Colocalization of in vivo and ex vivo results is demonstrated. Slices can then be recovered to be tested in conventional histology

Carbon monoxide and respiratory symptoms in young adult passive smokers: A pilot study comparing waterpipe to cigarette

Objectives: Studies have correlated second hand smoke (SHS) with many diseases, especially respiratory effects. The goal of this study was to measure the impact of SHS on the respiratory symptoms and exhaled carbon monoxide. Material and Methods: The study population consisted of 50 young workers in restaurants serving waterpipes, 48 university students who sit frequently in the university cafeteria where cigarette smoking is allowed and 49 university students spending time in places where smoking is not allowed. Subjects completed questionnaires on socio-demographic characteristics, respiratory symptoms and exposure to SHS. Exhaled carbon monoxide levels were measured. ANOVA and Chi-square tests were used when applicable as well as linear and logistic regression analysis. Results: Exposure to cigarette smoke in university (adjusted odds ratio (ORa) = 6.06) and occupational exposure to waterpipe smoke (ORa = 7.08) were predictors of chronic cough. Being married (ORa = 6.40), living near a heavy traffic road (ORa = 9.49) or near a local power generator (ORa = 7.54) appeared responsible for chronic sputum production. Moreover, predictors of chronic allergies were: being male (ORa = 7.81), living near a local power generator (ORa = 5.52) and having a family history of chronic respiratory diseases (ORa = 17.01). Carbon monoxide levels were augmented by the number of weekly hours of occupational exposure to waterpipe smoke (β = 1.46) and the number of daily hours of exposure to cigarette smoke (β = 1.14). Conclusions: In summary, young non-smoker subjects demonstrated more chronic cough and elevated carbon monoxide levels when exposed to SHS while the effect of waterpipe was even more evident

Regulation de l'expression genetique au niveau de la traduction dans l'operon infC-rpmI-rplT chez Escherichia coli

SIGLEINIST T 77625 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Activation de la transcription du rétrotransposon Ty1 de la levure Saccharomyces cerevisiae par la carence sévère en adénine

Les rétrotransposons sont des entités génétiques capables de se déplacer dans les génomes eucaryotes. Activés par des stress environnementaux, ils jouent un rôle majeur dans la structure, l évolution et l expression des génomes. Le rétrotransposon Ty1 de la levure S. cerevisiae est un modèle de l étude de la régulation et de l impact des rétrotransposons. La transcription et la mobilité de Ty1 sont activées dans une souche privée d adénine, déficiente dans la voie de biosynthèse de l AMP, conditions nommées carence sévère en adénine . L objectif de ma thèse a été de comprendre l activation de l expression de Ty1 par cette carence et d étudier l impact de cette activation sur le génome de la levure. Nous avons montré que la région longue terminale de Ty1, où démarre la transcription, est suffisante pour permettre la régulation. Nous avons aussi découvert que la carence modifie la transcription de gènes adjacents au promoteur de Ty1. Nous avons montré une corrélation entre l activation de la transcription de Ty1 et la diminution de l ATP cellulaire. De plus, un mutant qui crée directement un déficit en ATP, induit l activation de la transcription de Ty1 et mime les conditions de carence sévère en adénine. Le déficit en ATP pourrait donc être le signal de l activation de Ty1PARIS-BIUSJ-Thèses (751052125) / SudocPARIS-BIUSJ-Physique recherche (751052113) / SudocSudocFranceF