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Novel nanocomposite thin films by pulsed laser processes for plasmonic based sensing of cancer markers
No full textInternational audienceThis communication presents the development by pulsed laser deposition processes, of a novel nanocomposite thin film architecture as a highly sensitive plasmonic platform for rapid and early-stage disease diagnosis. The bio-detection principle is based on surface plasmon polaritons (SPP) existing at the interface between a metallic thin film and a dielectric, aiming to achieve high sensitivities and detect small analytes in very low concentrations (lower than fM concentration).Nanocomposite thin films are deposited on a glass substrate and are constituted of an ultra-thin (12 nm) Al2O3 matrix with embedded silver nanoparticles (diameter 2.3 nm), covered by a 48 nm gold layer. This architecture, combining localized surface plasmon resonance (LSPR) in nanoparticles with propagating SPR that exists in the gold film in a single material, can result in enhanced sensitivities.These plasmonic nanocomposites were made in a single reactor coupling two laser processes and developed by our group [1]. The well-known Pulsed Laser Deposition (PLD) method enables the deposition of thin films (Al2O3 matrix and gold upper layer) with high quality and offers the possibility to manage accurately their thicknesses. The associated free cluster generator developed for nanoparticles (NPs) synthesis with a diameter in the range 1-10 nm with quasi-monodisperse size distribution is used for silver NPs fabrication.A specific detection method based on lateral position shift of the reflected wave, known as Goos-Hänchen (GH) shift applied to this highly performing material results in high detection levels, with an ultra-high sensitivity up to 3.3×108 nm.RIU-1. The detection of cancer markers in sub-attomole concentrations was achieved, demonstrating the excellent potentials of the architecture for sensing with the highest detection level ever reached [2]. It is important to emphasize that these fully biocompatible sensors do not require functionalization before detection tests, making them easier to use compared to other platforms.This work was partially supported by the LabEx SigmaLim ANR-10-LBX-0074-01, laboratory of excellence launched by the French Ministry of Higher Education and Research between the XLIM and IRCER Research Institutes.[1] M. Gaudin et al., « A dual nanosecond-pulsed laser setup for nanocomposite synthesis—Ag nanoparticles in Al2O3/VO2 matrix », J. Appl. Phys., vol. 125, no 5, p. 054301, févr. 2019, doi: 10.1063/1.5058107.[2] S. Zhu et al., « Label-free biosensing with singular-phase-enhanced lateral position shift based on atomically thin plasmonic nanomaterials », Light Sci. Appl., vol. 13, no 1, p. 2, janv. 2024, doi: 10.1038/s41377-023-01345-6
Toxoplasma gondii en Amérique du Sud : un parasite zoonotique ancien, une émergence récente
No full textInternational audienceToxoplasma gondii, agent de la toxoplasmose, est un parasite présent chez environ 30 % de la population mondiale, et transmis à l’humain par le chat et les autres félidés. Généralement considéré comme bénin, il peut pourtant provoquer des formes graves de la maladie, en particulier en Amérique du Sud. Dans cette région, des cas sévères touchent même des personnes immunocompétentes, avec des atteintes oculaires pouvant mener à la cécité, ou à des formes disséminées potentiellement mortelles. Nous avons analysé un jeu de données mondial de 156 génomes de T. gondii —le plus grand jeu de données à ce jour. Nous montrons que, malgré la présence ancestrale de T. gondii en Amérique du Sud, les populations domestiques modernes de ce parasite sur ce continent sont issues d'hybridations massives entre des lignées domestiques européennes et africaines introduites par les colons européens, et des souches sauvages sud-américaines natives, incluant les souches amazoniennes particulièrement pathogènes pour l’humain. Ces hybridations, favorisées par les activités humaines (notamment l’introduction pour la première fois du chat dans les Amériques), auraient donné naissance à des parasites à la fois mieux adaptés à l’environnement domestique et plus pathogènes pour l’humain. Aujourd’hui, ces souches infectent probablement plus de 100 millions de personnes sur ce continent, et pourraient être à l’origine de la prévalence disproportionnée des formes sévères de toxoplasmose dans cette région
Parcours de soins et recours à la médecine complémentaire et alternativechez les patients atteints de cancers digestifs au Bénin : Enquête qualitative
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EJPC @ a Glance: Lipoprotein(a): new insights on an old enemy
No full textInternational audienceLipoprotein(a) [Lp(a)], a genetically determined atherogenic lipoprotein associated with several cardiovascular diseases, was first discovered by Kåre Berg in 1963. However, recognition of the importance of Lp(a) for cardiovascular disease followed much later. With the advent of targeted therapies for Lp(a), there has been renewed interest in Lp(a) and a rapid growth in research in this area. In this issue of the European Journal of Preventive Cardiology, several studies provide novel insights about Lp(a) and its role in disease.As a genetic risk factor for cardiovascular disease, Lp(a) levels have been considered to remain stable in individuals over time. In ‘Intra-individual variability in lipoprotein(a) levels: findings from a large academic health system population’, a study from the USA, Awad et al.1 evaluated nearly 12 000 adult participants with repeat Lp(a) testing. Variability over time in Lp(a) levels was appreciated, with 25% of individuals experiencing a change ≥ 10 mg/dL. However, the variability in Lp(a) was most relevant in those with borderline Lp(a) of 30–50 mg/dL; 51.2% of these individuals had a change in Lp(a) risk category. In contrast, ≥90% of those with normal (<30 mg/dL) or high (≥50 mg/dL) Lp(a) remained in the same group over time
A Legística da RSE no Direito OHADA
No full textInternational audienceDas Buch mit dem Titel „Die Legistik der CSR im OHADA-Recht“ ist eine zukunftsorientierte Studie über die Einführung der gesellschaftlichen Unternehmensverantwortung (Corporate Social Responsibility – CSR) in den normativen Rahmen des OHADA. Mit diesem Werk verfolgt der Autor zwei Hauptziele.Das erste besteht darin, Juristinnen und Juristen in die Legistik einzuführen, die bislang ein vernachlässigter Bereich der juristischen Ausbildung an den Fakultäten geblieben ist. Das zweite Ziel ist die Anwendung der Prinzipien der Legistik auf das kontroverse Thema der gesellschaftlichen Unternehmensverantwortung.The book titled “The Legistics of CSR in OHADA Law” is a forward-looking study on the introduction of Corporate Social Responsibility (CSR) into the OHADA normative framework. Through this work, the author addresses two key objectives.The first is to introduce legal scholars to legistics, which has long remained the neglected aspect of law school curricula. The second is to apply the principles of legistics to the controversial subject of Corporate Social Responsibility.El libro titulado «La legística de la RSE en el derecho OHADA» es un estudio prospectivo sobre la introducción de la Responsabilidad Social Empresarial (RSE) en el marco normativo del OHADA. A través de esta obra, el autor responde a dos objetivos fundamentales.El primero es iniciar a los juristas en la legística, que hasta ahora ha sido el aspecto olvidado de los programas de formación en las facultades de derecho. El segundo es aplicar los principios de la legística al tema controvertido de la Responsabilidad Social Empresarial.L'ouvrage intitulé « la légistique de la RSE en droit OHADA » est une étude prospective sur l'introduction de la responsabilité sociétale des entreprises dans le « corpus normatif » de l'OHADA. A travers cet ouvrage, l'auteur répond à deux impératifs. Le premier est l'initiation des juristes à la légistique qui demeure jusqu'alors le parent pauvre des curricula de formation dans les facultés de droit. Le deuxième est l'application des principes de légistique au sujet controversé qu'est la responsabilité sociétale des entreprises.O livro intitulado “A Legística da RSE no Direito OHADA” é um estudo prospectivo sobre a introdução da Responsabilidade Social Empresarial (RSE) no quadro normativo do OHADA. Por meio desta obra, o autor responde a dois objetivos fundamentais.O primeiro é introduzir os juristas à legística, que até agora tem sido o aspecto negligenciado dos currículos das faculdades de direito. O segundo é aplicar os princípios da legística ao tema controverso da Responsabilidade Social Empresarial
Study of Thermomechanical Behaviour of Refractory Materials Under Thermal Gradient. Part II—Experimental and Numerical Analysis on the Example of a Shaped Alumina Spinel Refractory
No full textInternational audienceBackgroundImproving the understanding of how a refractory material responds to thermal shocks and allowing the validation of finite element models require a valuable tool for experimental data collection.Objective This paper presents a comprehensive thermal shock behaviour analysis of an alumina spinel refractory material using the recently developed device in part I.Methods Based on real material properties evolving with temperature and on characteristics of the applied laser beam sequence, the Finite Element Method transient heat transfer model has been validated through the experimental displacement/strain/temperature fields obtained with the developed device.ResultsThe experimental evolution of strain and temperature fields at the bottom of the sample during the applied thermal shock testing sequence have been found to be similar to those evaluated by FEM modelling. Three-dimensional evolutions of stress state within the sample during the applied laser sequence leads to thermal bowing of the sample which is identified by both experimental measurements and by FEM modelling. An occurrence of a macrocrack has been clearly detected at a specific laser heating cycle using Two-Part Digital Image Correlation technique.Conclusions The innovative approach, presented in these two linked articles, offers a comprehensive understanding of the thermal shock behaviour of a representative refractory material using both numerical simulations and experimental techniques
Epidemiology of peripheral neuropathies in sub-Saharan Africa from 2000 to 2020: systematic review and meta-analysis
No full textInternational audienceIntroduction: Epidemiological studies on peripheral neuropathy (PN) in sub-Saharan Africa (SSA) have been conducted out in various target populations. This systematic review and metaanalysis aim to present and update available descriptive data on PN in SSA from 2000 to 2020. Methods: Research was performed in indexed databases PubMed (MEDLINE), Web of Science, Google Scholar, Scopus, African Journals Online, and grey literature databases. Studies were selected according to the PRISMA methodology and data were extracted using a collection grid. A meta-analysis with a random-effects model was performed to determine the pooled frequency measures of PNs. Results: Overall, 116 studies were included in this review, comprising 75,227 subjects (59.71% male, mean age range 9-68.8 years). The highest number of studies were conducted in East Africa (n = 47; 40.5%). The pooled hospital frequency of PN was 39.6% ([95% CI: 34.2-45.2], I 2 = 99.32%), the pooled prevalence was 4.30% ([95% CI: 2.50-6.50], I 2 = 97.52%), and the pooled hospital incidence was 15.60% per year ([95% CI: 5.10-29.70], I 2 = 98.78%). Pooled hospital frequency of PN was higher in diabetic patients (50.30% [95% CI: 28.30-66.70], I 2 = 99%) and in Southern Africa (44.30% [95% CI: 27.80-61.10], I 2 = 99%). For using electroneuromyogram as a diagnostic tool, the pooled hospital frequency of PN was 76.80% ([95% CI: 67.30-85.40], I 2 = 67%). The frequency of polyneuropathy subgroup was 34.40% ([95% CI: 29.90-46.90], I 2 = 99.20%). Conclusion: PNs are frequent in SSA and particularly in certain target groups. It is important to improve preventive measures for HIV and diabetes and increase the understanding of risk factors associated with PN
