Hydrophobic double walled carbon nanotubes interaction with phopholipidic model membranes: 1H-, 2H-, 31P NMR and ESR study

The interactions of carbon nanotubes synthesized by catalytic chemical vapour deposition with phospholipidic bilayers, mimicking biological membranes, have been investigated using solid state 31P- and 2H NMR, 1H- and 31P NMR in liquids and ESR studies. It was found that carbon nanotubes can integrate the bilayer, depending on the overall cohesion of the membrane used. Whereas no direct interaction can be observed in small unilamellar vesicles or directly in the presence of short-chained phospholipids, carbon nanotubes incorporate into the membrane of multibilayers. The result is a significant 2–3 K lowering of the transition temperature in multibilayers of dimyristoyl lecithins, which is more markedly associated with increased fluidity in the most superficial part of the membrane below the transition temperature (292–300 K range). However, no ionophoric property was found on large unilamellar vesicles

L'embauche des jeunes résiste en Bourgogne

En ligne sur le site de l'IREDU : http://iredu.u-bourgogne.fr/images/stories/Documents/Publications_chercheurs/2016/16056.pdfNote de valorisation diffusée par l'académie de Dijon et le centre associé CEREQ associé à l'IREDULa transition formation - vie professionnelle ainsi que le chômage des jeunes sont au coeur des débats actuels. Dans quelles conditions les jeunes sortis à différents niveaux du système éducatif, du CAP au BTS, s'insèrent-ils dans le monde du travail en Bourgogne ? Pour connaître le devenir des anciens élèves et apprentis, le ministère de l'Éducation nationale réalise depuis de nombreuses années des enquêtes, avec l'appui des lycées et des centres de formation d'apprentis

Active Probe Emitting HF Electromagnetic Fields and Piezoelectric Emissions in Association with Local Carbon Nanotubes : Preliminary Tests in C6 Glioma Cell Death Induction: A Possible Application in Glioblastoma Therapeutics ?

n/

Carbon nanotubes induce inflammation but decrease the production of reactive oxygen species in lung

With the rapid spread of carbon nanotubes (CNTs) applications, the respiratory toxicity of these compounds has attracted the attention of many scientists. Several studies have reported that after lung administration, CNTs could induce granuloma, fibrosis, or inflammation. By comparison with the mechanisms involved with other toxic particles such as asbestos, this effect could be attributed to an increase of oxidative stress. The aim of the present work was to test this hypothesis in vivo. Mice were intranasally instilled with 1.5 mg/kg of double walled carbon nanotubes (DWCNTs). Six, 24, or 48 h after administration, inflammation and localisation of DWCNTs in lungs were microscopically observed. Local oxidative perturbations were investigated using ESR spin trapping experiments, and systemic inflammation was assessed by measuring the plasma concentration of cytokines TNF-α, IL-1α, IL-1β, IL-6, IGF-1, Leptin, G-CSF, and VEGF. Examination of lungs and the elevation of proinflammatory cytokines in the plasma (Leptin and IL-6 at 6 h) confirmed the induction of an inflammatory reaction. This inflammatory reaction was accompanied by a decrease in the local oxidative stress. This effect could be attributed to the scavenger capability of pure CNTs

Où en est le mouvement ouvrier américain aujourd’hui ?

Cet entretien a été réalisé à Paris en novembre 2003 par Jean‑Christian Vinel. Marianne Debouzy est professeur émérite à Paris‑VIII. Spécialiste d’histoire ouvrière américaine, elle a notamment publié Le Capitalisme sauvage aux États‑Unis (Seuil, 1972), Travail et Travailleurs aux États‑Unis (La Découverte, 1990), et La classe ouvrière dans l’histoire américaine (Nancy : Presses universitaires de Nancy, 1989). Elle vient de diriger un numéro spécial du Mouvement Social sur la question des droits et des mouvements sociaux (n°203, avril juin 2003) [http://biosoc.univ‑paris1.fr/recherche/mvtsoc/num203.htm.

La poupée Barbie

L'apparition de la poupée Barbie en 1959 ­ c'est-à-dire la substitution d'une poupée femme à une poupée enfant ­ marque une rupture dans la socialisation des petites filles. Pur produit des années 1950, la poupée Barbie s'adapte à toutes les décennies qui suivent car elle est avant tout le symbole d'une société de consommation qui sait récupérer toutes les modes, même celles qui paraissent les plus avancées. Elle est aussi le symbole du simulacre dans un monde qui est de plus en plus le monde du faux-semblant.The appearence of the Barbie doll in 1959, that is the replacing of a child doll by a woman doll, marked a turning point in the socializing of little girls. A pure product of the 50s,the Barbie doll has adapted to the following decades for she is above all symbol of a consumer society which knows how to coopt all fads. She is also emblematic of a world in wich human beings are treated more and more like pieces of plastic and in wich it is more difficult to distinguish make-believe and reality

Biological effects of double-walled carbon nanotubes on the innate immune system: An in vitro study on THP-1 human monocytes

DWCNTs have numerous industrial and biomedical applications and several studies reported that they could act as immunomodulator systems. The immune system is the first line of defence of the human body when exposed to particulate matter. In order to investigate DWCNTs’ role on innate immunity, we used THP-1 monocytic cells for the purpose of this study. We showed that DWCNTs were not cytotoxic until 6 h, 24 h, 48 h and 72 h of incubation with THP-1 monocytic cells (concentrations tested from 10 to 50 μg/mL). From 6 h to 72 h of incubation of THP-1 cells with DWCNTs, we measured a significant increase of the baseline cell index using xCELLigence® technology showing cell adhesion. After 24 h of exposure, DWCNTs agglomerates were localized in THP-1 monocyte cytoplasm and cell adhesion was observed simultaneously with a significant increase in the expression of CD11b and CD14 cell surface proteins. Pro-inflammatory cytokine secretion (IL-1β, IL-6, IL-8, TNF-α and IL-10) was also measured in supernatants after 6 h or 24 h of exposure to DWCNTs. This pro-inflammatory response was increased in THP-1 monocytic cells pre-treated with LPS. Altogether, our data indicate that DWCNTs induce an increased pro-inflammatory response of THP-1 monocytes and seem to modulate cell surface protein expression confirming that DWCNTs could act as stimulators of innate immunity

Chronic Electromagnetic Exposure at Occupational Safety Level Does Not Affect the Metabolic Profile nor Cornea Healing after LASIK Surgery

LASIK eye surgery has become a very common practice for myopic people, especially those in the military. Sometimes undertaken by people who need to keep a specific medical aptitude, this surgery could be performed in secret from the hierarchy and from the institute medical staff. However, even though the eyes have been previously described as one of the most sensitive organs to electromagnetic fields in the human body, no data exist on the potential deleterious effects of electromagnetic fields on the healing eye. The consequences of chronic long-lasting radar exposures at power density, in accordance with the occupational safety standards (9.71 GHz, 50 W/m2), were investigated on cornea healing. The metabolic and clinical statuses after experimental LASIK keratotomy were assessed on the different eye segments in a New Zealand rabbit model. The analysis methods were performed after 5 months of exposure (1 hour/day, 3 times/week). Neither clinical or histological examinations, nor experimental data, such as light scattering, 1H-NMR HRMAS metabolomics, 13C-NMR spectra of lipidic extracts, and antioxidant status, evidenced significant modifications. It was concluded that withdrawing the medical aptitude of people working in electromagnetic field environments (i.e., radar operators in the navy) after eye surgery was not justified