Publications by authors named "Jacques-Aurelien Sergent"

A roadmap was developed to strengthen standardisation activities for risk governance of nanotechnology. Its baseline is the available standardised and harmonised methods for nanotechnology developed by the International Organization for Standardization (ISO), the European Committee for Standardization (CEN), and the Organisation for Economic Co-operation and Development (OECD). In order to identify improvements and needs for new themes in standardisation work, an analysis of the state-of-the-art concepts and interpretations of risk governance of nanotechnology was performed.

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Silica (either crystalline or amorphous) is widely used for different applications and its toxicological assessment depends on its characteristics and intended use. As sustained inflammation induced by crystalline silica is at the root of silicosis, investigating the inflammatory effects induced by amorphous silicas and their persistence is needed. For the development of new grades of synthetic amorphous silicas, it is also desirable to be able to understand better the factors underlying potential adverse effects.

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To develop new therapeutic molecules, it is essential to understand the biological effects and targets of clinically relevant compounds. In this article, we describe the extraction and characterization of two alkaloids from the roots of -curine and guattegaumerine. The effect of these alkaloids on the multidrug efflux pump ABCB1 (MDR1/P-Glycoprotein) and their antiproliferative properties were studied.

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Synthetic amorphous silica (SAS) is a nanomaterial used in a wide variety of applications, including the use as a food additive. Two types of SAS are commonly employed as a powder additive, precipitated silica and fumed silica. Numerous studies have investigated the effects of synthetic amorphous silica on mammalian cells.

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Immunotoxicology comprises not only toxicity toward immune cells, but also biological reactions from immune cells exposed to toxicants, reactions that may have deleterious effects at the organismal level. Within this wide frame, a specific case of interest is represented by the response of macrophages to particulate materials, with the epitome examples of asbestos and crystalline silica. For such toxicants that are both persistent and often encountered in an occupational setting, i.

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The ECETOC NanoApp was developed to support industry in the registration of sets of nanoforms, as well as regulators in the evaluation of these registration dossiers. The ECETOC NanoApp uses a systematic approach to create and justify sets of similar nanoforms, following the ECHA guidance in a transparent and evidence-based manner. The rational and decision rules behind the ECETOC NanoApp are described in detail in "Janer, G.

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Unlabelled: Considerable evidence exists that bacteria detect eukaryotic communication molecules and modify their virulence accordingly. In previous studies, it has been demonstrated that the increasingly antibiotic-resistant pathogen Pseudomonas aeruginosa can detect the human hormones brain natriuretic peptide (BNP) and C-type natriuretic peptide (CNP) at micromolar concentrations. In response, the bacterium modifies its behavior to adapt to the host physiology, increasing its overall virulence.

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Silica mesoporous nanoparticles have been recently selected for a wide range of applications from electronics to medicine due to their intrinsic properties. Among medical applications, drug delivery using SiO(2) nanoparticles by oral route is under study. Major benefits are expected including higher specificity and sensitivity together with side effect reduction.

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