Publications associées à Théorie radicalaire du vieillissement

Charge-Transfer States in Organic Nanowires

Charge separation processes in organic semiconductors play a pivotal role in diverse applications ranging from photovoltaics to photocatalysis. Understanding these mechanisms, particularly the role of hybrid charge-transfer (CT) states, is essential for ad ...

EPFL2024

Detecting the metabolism of individual yeast mutant strain cells when aged, stressed or treated with antioxidants with diamond magnetometry

Mayeul Sylvain Chipaux

Free radicals play a key role in the ageing process. However, free radicals are small, reactive and short lived and thus challenging to measure. We utilize a new technique called diamond magnetometry for this pur-pose. We make use of nitrogen vacancy cente ...

ELSEVIER SCI LTD2023

Epigenetic ageing accelerates before antiretroviral therapy and decelerates after viral suppression in people with HIV in Switzerland: a longitudinal study over 17 years

Jacques Fellay, Christian Axel Wandall Thorball

Background Accelerated epigenetic ageing can occur in untreated HIV infection and is partially reversible with effective antiretroviral therapy (ART). We aimed to make a long-term comparison of epigenetic ageing dynamics in people with HIV during untreated ...

ELSEVIER2023

Evaluation of the role of superoxide radical as chain carrier for the formation of hydroxyl radical during ozonation

Urs von Gunten, Gang Yu, Yan Wang

Superoxide radicals (O-2(center dot-)) have been suggested as an important chain carrier in the radical chain reaction that promotes ozone (O-3) decomposition to hydroxyl radicals ((OH)-O-center dot) during ozonation. However, due to the difficulty in meas ...

PERGAMON-ELSEVIER SCIENCE LTD2023

Aging Fly Cell Atlas identifies exhaustive aging features at cellular resolution

Maria Brbic, Sandy Lee

Aging is characterized by a decline in tissue function, but the underlying changes at cellular resolution across the organism remain unclear. Here, we present the Aging Fly Cell Atlas, a single-nucleus transcriptomic map of the whole aging Drosophila. We c ...

American Association for the Advancement of Science2023

Influence of DNP Polarizing Agents on Biochemical Processes: TEMPOL in Transient Ischemic Stroke

Mor-Miri Mishkovsky, Jean-Noël Hyacinthe, Mario Gaetano Lepore, Thanh Phong Kevin Lê, Lara Buscemi Estefanell

Hyperpolarization of 13C by dissolution dynamic nuclear polarization (dDNP) boosts the sensitivity of magnetic resonance spectroscopy (MRS), making possible the monitoring in vivo and in real time of the biochemical reactions of exogenously infused 13C-lab ...

2023

V-ATPase/TORC1-mediated ATFS-1 translation directs mitochondrial UPR activation in C. elegans

Johan Auwerx, Kristina Schoonjans, Felix Naef, Xiaoxu Li, Jia Liu, Hao Li, Wen Gao, Nagammal Neelagandan, Yang Li, Amélia Lalou, Yuan Liu

To adapt mitochondrial function to the ever-changing intra- and extracellular environment, multiple mitochondrial stress response (MSR) pathways, including the mitochondrial unfolded protein response (UPRmt), have evolved. However, how the mitochondrial st ...

Rockefeller University Press2022

Flowing Gas Experiments Reveal Mechanistic Details of Interfacial Reactions on a Molecular Level at Knudsen Flow Conditions

Christian Ludwig, Michel Rossi, Riccardo Iannarelli

Knudsen flow experiments and its interpretation in terms of adsorption/desorption kinetics as well as quantitative uptake on substrates of interest is presented together with the description of critical design parameters of the Knudsen Flow Reactor (KFR). ...

2022

Quantum Sensing of Free Radicals in Primary Human Dendritic Cells

Mayeul Sylvain Chipaux

Free radicals are crucial indicators for stress and appear in all kinds of pathogenic conditions, including cancer, cardiovascular diseases, and infection. However, they are difficult to detect due to their reactivity and low abundance. We use relaxometry ...

AMER CHEMICAL SOC2022

Optical properties and photochemical production of hydroxyl radical and singlet oxygen after ozonation of dissolved organic matter

Urs von Gunten, Frank Jonathan Leresche

This study focuses on the effects of ozonation on the optical and photochemical properties of dissolved organic matter (DOM). Upon ozonation, a decrease in light absorption properties of DOM was observed concomitantly with a large increase in singlet oxyge ...

ROYAL SOC CHEMISTRY2021

Permanganate Reduction by Hydrogen Peroxide: Formation of Reactive Manganese Species and Superoxide and Enhanced Micropollutant Abatement

Urs von Gunten, Ke Xu

Permanganate (MnO4-, Mn(VII)) is widely applied at the initial stage of water treatment to, e.g., abate taste and odor compounds, Mn(II) and Fe(II). However, its selectivity limits its application for micropollutant abatement. Hydrogen peroxide (H2O2), whi ...

AMER CHEMICAL SOC2021

Generation of hydroxyl radical during chlorination of hydroxyphenols and natural organic matter extracts

Urs von Gunten, Eva Maria Rodriguez Franco

The generation of hydroxyl radicals ((OH)-O-center dot) during the chlorination of air saturated solutions of different hydroxyphenols (hydroquinone, resorcinol, catechol, gallic and tannic acids) at pH 7 has been determined by the formation of phenol (in ...

2020

Nanodiamond Relaxometry-Based Detection of Free-Radical Species When Produced in Chemical Reactions in Biologically Relevant Conditions

Mayeul Sylvain Chipaux

Diamond magnetometry is a quantum sensing method involving detection of magnetic resonances with nanoscale resolution. For instance, T1 relaxation measurements, inspired by equivalent concepts in magnetic resonance imaging (MRI), provide a signal that is e ...

AMER CHEMICAL SOC2020

Persulfate-Based Advanced Oxidation: Critical Assessment of Opportunities and Roadblocks

Urs von Gunten

Reports that promote persulfate-based advanced oxidation process (AOP) as a viable alternative to hydrogen peroxide-based processes have been rapidly accumulating in recent water treatment literature. Various strategies to activate peroxide bonds in persul ...

AMER CHEMICAL SOC2020

Improving visible light photocatalytic inactivation of E. coli by inducing highly efficient radical pathways through peroxymonosulfate activation using 3-D, surface-enhanced, reduced graphene oxide (rGO) aerogels

César Pulgarin, Stefanos Giannakis, Minoo Karbasi

In this work, we synthesized highly porous reduced graphene oxide foams, presenting augmented antibacterial activity in presence/absence of peroxymonosulfate (PMS). To date, this is the first investigation of photocatalytic PMS disinfection by 3D-rGO mater ...

ELSEVIER SCIENCE SA2020

Experimental evidence for long-range stabilizing and destabilizing interactions between charge and radical sites in distonic ions

Ganna Gryn'ova

Polarizable radical sites in distonic radical anions are stabilized by ostensibly remote negative charges. Computational evidence suggests bond dissociation energies of closed-shell precursors are significantly lowered by through-space interactions with a ...

ELSEVIER SCIENCE BV2019

Yearlong variability of oxidative potential of particulate matter in an urban Mediterranean environment

Athanasios Nenes

The oxidative potential (OP) of fine and coarse fractions of ambient aerosols was studied in the urban environment of Athens, Greece. OP was quantified using a dithiothreitol (DTT) assay, applied to the water soluble fraction of aerosol that was extracted ...

Elsevier2019

The RNA-Binding Protein PUM2 Impairs Mitochondrial Dynamics and Mitophagy During Aging

Johan Auwerx, Kristina Schoonjans, Bernard Schneider, Graham Knott, Davide D'Amico, Vera Monica Lemos Da Silva, Mario Romani, Vincenzo Sorrentino, Adrienne Joëlle Laurence Mottis, Hao Li, Francesca Potenza

Little information is available about how post-transcriptional mechanisms regulate the aging process. Here, we show that the RNA-binding protein Pumilio2 (PUM2), which is a translation repressor, is induced upon aging and acts as a negative regulator of li ...

CELL PRESS2019

De novo NAD(+) synthesis enhances mitochondrial function and improves health

Johan Auwerx, Kristina Schoonjans, Dongryeol Ryu, Elena Katsyuba, Adrienne Joëlle Laurence Mottis, Karim Laurent Gariani, Marika Olga Zietak

Nicotinamide adenine dinucleotide (NAD(+)) is a co-substrate for several enzymes, including the sirtuin family of NAD(+)-dependent protein deacylases. Beneficial effects of increased NAD(+) levels and sirtuin activation on mitochondrial homeostasis, organi ...

NATURE PUBLISHING GROUP2018

Effect of light and oxygen on repetitive bacterial inactivation on uniform, adhesive, robust and stable Cu-polyester surfaces

César Pulgarin, Juan Kiwi, Sami Rtimi, Rosendo Sanjines

This study reports new findings on the sputtered Cu-polyester (Cu-PES) bacterial inactivation under low intensity visible light (lambda > 400 nm). Cu-PES samples sputtered for 160 s led to the complete inactivation of E. coli in anaerobic and aerobic media ...

De Gruyter Mouton2017