L’ampoule sous tension

Image d’ouverture Laurent Seroussi. Masayo, série Ray of Ligth, 2016. (Galerie Antonin Borgeaud) © Frédéric Joulian Comment l’impératif contemporain de durabilité affecte-t-il la trajectoire d’un objet technique, l’ampoule électrique ? L’article repose sur la distinction entre développement durable institutionnel et soutenabilité, théorisée notamment par le philosophe de la modernité Michel Puech, pour identifier deux types d’innovations et deux rapports à la technique radicalement différent..

L'ampoule sous tension

Cet article explore la façon dont l'impératif contemporain de durabilité affecte la trajectoire d'un objet technique, l'ampoule électrique. Il identifie les innovations qui transforment l'ampoule dans sa matérialité et en propose une analyse fondée sur la distinction entre développement durable institutionnel et soutenabilité. La première partie identifie les transformations de l'ampoule dues aux impératifs du développement durable institutionnel qui se divisent en trois types de normes: efficacité énergétique, traitement du déchet et valorisation de la matière. La deuxième partie s'intéresse à sa réappropriation par des initiatives portées par d'autres imaginaires et d'autres enjeux, notamment la durée de vie, l'appropriation culturelle et la résilience permettant une plus grande indépendance face au réseau électrique.This paper explores how the modern imperative of sustainability impacts the evolution of a technical object : the electric lightbulb. It identifies innovations that transform the lightbulb in its materiality and bases its analysis on the dichotomy between institutionnal sustainable development and convivial sustainability. The first part focuses on how institutional sustainable development transforms the lightbulb, through three normativities : energy efficiency, waste management and material recovery. The second part explores other stakes and other imaginaries carried by non-institutionnal sustainability, especially life expectancy, cultural appropriation and resilience allowing to be less dependent on the grid

Where the Harm Comes From: Ethics of Mediating Collectives

This article defines the intermediate level between personal agency and global issues of injustice as a complex system of mediating collectives, the agency of which must be addressed specifically in organizational and ontological but also in ethical and political terms. We target three domains of global injustice: economic, environmental, and gender-related, following the threads of briefly stated cases in these domains. Our conclusion suggests recommendations for dealing more realistically and more efficiently with global injustice that obstinately thrives from somewhere deep into the structures of the contemporary world. Our recommendations will bear on (a) individual responsibility in a collective, (b) virtuous direct and indirect action, (c) awareness of and communication with interdependent collectives, (d) optimal communication within every collective, (e) readiness for joint-action as an authentic group-agent

Gut microbiota-derived propionate reduces cancer cell proliferation in the liver

Peer reviewedPublisher PD

Degradation of azo dye (Acid orange 7) in a microbial fuel cell: comparison between anodic microbial-mediated reduction and cathodic laccase-mediated oxidation

More than 80 per cent of wastewater from industries is discharged into receiving water bodies without any pollution control. Microbial fuel cells (MFCs) are a promising technology for the simultaneous treatment of wastewater and electricity production. With regard to azo-dye containing wastewater (e.g. from textile manufacturing), the dye may be fed via the anode chamber containing electrochemically active bacteria or via the cathode chamber containing laccase enzyme as catalyst for oxygen reduction. This study investigated which of the two approaches is the best with regard to rate of decolourization of the dye (Acid orange 7), COD reduction and electricity production. The power density was higher for the MFCDye cathode (50±4 mW m-2, COD reduction 80.4±1.2%) compared with 42.5±2.6 mW m-2 (COD reduction 69±2%) for MFCDye anode. The time required for decolourization was longer in the MFCDye anode (Shewanella oneidensis) where only 20% decolourization was obtained after 24 h compared to 80% for the MFCDye cathode. The anodic dye degradation products were unstable when exposed to air resulting in regaining of colour. In case of degradation by laccase in the cathode chamber, the decolourization products were stable and simpler in chemical structure as determined by GC-MS. This work suggests that feeding azo dyes in cathode chambers of MFCs containing laccase is a better way of treating the dyes compared to the commonly used approach of feeding the dye in the anode chamber provided enzyme activity can be sustained

Vitamin K Supplementation in Postmenopausal Women with Osteopenia (ECKO Trial): A Randomized Controlled Trial

Angela Cheung and colleagues investigate whether vitamin K1 can prevent bone loss among postmenopausal women with osteopenia

Dietary vitamin K intake in relation to cancer incidence and mortality: results from the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition (EPIC-Heidelberg)

BACKGROUND: Anticarcinogenic activities of vitamin K have been observed in animal and cell studies. OBJECTIVE: On the basis of the growth inhibitory effects of vitamin K as observed in a variety of cancer cell lines, we hypothesized that dietary intake of phylloquinone (vitamin K(1)) and menaquinones (vitamin K(2)) may be associated with overall cancer incidence and mortality. DESIGN: In the prospective EPIC-Heidelberg (European Prospective Investigation into Cancer and Nutrition-Heidelberg) cohort study, 24,340 participants aged 35-64 y and free of cancer at enrollment (1994-1998) were actively followed up for cancer incidence and mortality through 2008. Dietary vitamin K intake was estimated from food-frequency questionnaires completed at baseline by using HPLC-based food-composition data. Multivariate-adjusted hazard ratios (HRs) and 95% CIs were estimated by using Cox proportional hazards models. RESULTS: During a median follow-up time of >10 y, 1755 incident cancer cases occurred, of which 458 were fatal. Dietary intake of menaquinones was nonsignificantly inversely associated with overall cancer incidence (HR for the highest compared with the lowest quartile: 0.86; 95% CI: 0.73, 1.01; P for trend = 0.08), and the association was stronger for cancer mortality (HR: 0.72; 95% CI: 0.53, 0.98; P for trend = 0.03). Cancer risk reduction with increasing intake of menaquinones was more pronounced in men than in women, mainly driven by significant inverse associations with prostate (P for trend = 0.03) and lung (P for trend = 0.002) cancer. We found no association with phylloquinone intake. CONCLUSION: These findings suggest that dietary intake of menaquinones, which is highly determined by the consumption of cheese, is associated with a reduced risk of incident and fatal cancer

Epigallocatechin-3-gallate induces mesothelioma cell death via H2O2-dependent T-type Ca2+ channel opening

Malignant mesothelioma (MMe) is a highly aggressive, lethal tumour requiring the development of more effective therapies. The green tea polyphenol epigallocathechin-3-gallate (EGCG) inhibits the growth of many types of cancer cells. We found that EGCG is selectively cytotoxic to MMe cells with respect to normal mesothelial cells. MMe cell viability was inhibited by predominant induction of apoptosis at lower doses and necrosis at higher doses. EGCG elicited H2O2release in cell cultures, and exogenous catalase (CAT) abrogated EGCG-induced cytotoxicity, apoptosis and necrosis. Confocal imaging of fluo 3-loaded, EGCG-exposed MMe cells showed significant [Ca2+]irise, prevented by CAT, dithiothreitol or the T-type Ca2+channel blockers mibefradil and NiCl2. Cell loading with dihydrorhodamine 123 revealed EGCG-induced ROS production, prevented by CAT, mibefradil or the Ca2+chelator BAPTA-AM. Direct exposure of cells to H2O2produced similar effects on Ca2+and ROS, and these effects were prevented by the same inhibitors. Sensitivity of REN cells to EGCG was correlated with higher expression of Cav3.2 T-type Ca2+channels in these cells, compared to normal mesothelium. Also, Cav3.2 siRNA on MMe cells reduced in vitro EGCG cytotoxicity and abated apoptosis and necrosis. Intriguingly, Cav3.2 expression was observed in malignant pleural mesothelioma biopsies from patients, but not in normal pleura. In conclusion, data showed the expression of T-type Ca2+channels in MMe tissue and their role in EGCG selective cytotoxicity to MMe cells, suggesting the possible use of these channels as a novel MMe pharmacological target. \ua9 2012 Foundation for Cellular and Molecular Medicine/Blackwell Publishing Ltd

NADPH oxidase links endoplasmic reticulum stress, oxidative stress, and PKR activation to induce apoptosis

ER stress signaling involving calcium and CaMKII induces NADPH oxidase and oxidative stress, which amplify CHOP-mediated apoptosis via PKR activation

α-Tocopheryl succinate promotes selective cell death induced by vitamin K3 in combination with ascorbate

BACKGROUND: A strategy to reduce the secondary effects of anti-cancer agents is to potentiate the therapeutic effect by their combination. A combination of vitamin K3 (VK3) and ascorbic acid (AA) exhibited an anti-cancer synergistic effect, associated with extracellular production of H2O2 that promoted cell death. METHODS: The redox-silent vitamin E analogue a-tocopheryl succinate (a-TOS) was used in combination with VK3 and AA to evaluate their effect on prostate cancer cells. RESULTS: Prostate cancer cells were sensitive to a-TOS and VK3 treatment, but resistant to AA upto 3.2mM. When combined, a synergistic effect was found for VK3\u2013AA, whereas a-TOS\u2013VK3 and a-TOS\u2013AA combination showed an antagonist and additive effect, respectively. However, sub-lethal doses of AA\u2013VK3 combination combined with a sub-toxic dose of a-TOS showed to induce efficient cell death that resembles autoschizis. Associated with this cell demise, lipid peroxidation, DNA damage, cytoskeleton alteration, lysosomal\u2013mitochondrial perturbation, and release of cytochrome c without caspase activation were observed. Inhibition of lysosomal proteases did not attenuate cell death induced by the combined agents. Furthermore, cell deaths by apoptosis and autoschizis were detected. CONCLUSION: These finding support the emerging idea that synergistic combinations of some agents can overcome toxicity and other side-effects associated with high doses of single drugs creating the opportunity for therapeutically relevant selectivity