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Impact of static electric field on different freezing rates in quality preservation of scallops
No full textInternational audienceThis study investigates the impact of static electric field (SEF) assisted freezing at different freezing rates on the quality of scallops (Mizuhopecten yessoensis). Samples were frozen in static air at −20 °C, −40 °C, and − 60 °C with applied SEF intensities of 0, 2.77 × 105 V/m, 5.55 × 105 V/m, and 8.33 × 105 V/m. Key quality attributes, including nucleation temperature, phase transition time, textural properties, color changes, protein solubility, and microstructural integrity were evaluated. Results show that applying an electric field shortens the nucleation time. From an SEF of 0 to 8.33 × 105 V/m, the degree of supercooling has decreased by 1.14 °C, 1.87 °C, and 2.03 °C at freezing temperatures of −20 °C, −40 °C, and − 60 °C, respectively. The application of SEF also demonstrated an improvement in post-thaw texture, particularly chewiness and resilience, while minimizing structural damage to muscle fibers. Microstructural analysis revealed that 8.33 × 105 V/m SEF has reduced the ice crystal size by 29.01 %, 36.04 %, and 44.05 % at −20 °C, −40 °C, and − 60 °C, respectively, in comparison to the control group. Additionally, the color differences between the fresh and thawed samples were minimized under the highest electric field and fastest freezing rate condition at −60 °C. Interestingly, under slow freezing condition at −20 °C and 8.33 × 105 V/m SEF, ice crystal size, color difference, and other quality indicators approached those achieved by rapid freezing at −60 °C without SEF. This study confirms that electric field-assisted freezing enhances the quality of scallops and provides valuable insights for potential improvement of food freezing processes
Investigation of the colony size effect on light access and growth of the colonial microalga Botryococcus braunii in photobioreactor
No full textInternational audienceThe colonial microalga Botryococcus braunii is recognized for its original hydrocarbon content, making it a promising candidate for the production of biofuels and other bio-based products. However, challenges related to its slow photosynthetic growth rate hinder economically viable processes and large-scale applications. This study investigates the effect of colony size on light absorption and growth efficiency in B. braunii BOT-22. To examine this, large colonies were disrupted into smaller ones using a high-pressure homogenizer, resulting in a tenfold increase in the mass absorption cross-section (from 8.0 to 79 m2·kg−1), highlighting how colony size significantly affects light absorption. Next, cultivation in a photobioreactor allowed the calculation of the Mean Rate of Photon Absorption (MRPA), supporting a relationship between the colonial behavior of B. braunii and a photoprotective strategy. Higher incident light flux was associated with larger colonies, which is likely a mechanism to manage the light stress on embedded cells. Building on these results, medium-sized and larger colonies were successfully generated by applying different light conditions during pre-cultivation. Photobioreactor cultures of these medium-sized colonies (145 μm average diameter) showed 34 % higher biomass productivity (0.123 g·L−1·d−1 or 4.92 g·m2·d−1) and 74 % higher hydrocarbon productivity (0.033 g·L−1·d−1 or 1.30 g·m2·d−1) compared to the larger colonies (434 μm). These findings highlight the important role of optimizing colony size for better light absorption and productivity, providing valuable insights for improving photobioreactor performance in B. braunii cultivation
Améliorer la connaissance et la reconnaissance des interventions non médicamenteuses : implications pour la santé publique d’une étude participative et de consensus
No full textInternational audienceIntroduction: In the absence of a consensus on the definition and evaluation of non-pharmacological interventions (NPI)-despite the use of the concept by the World Health Organization, the French Health Authority, the Ministry of Health, and the European Centre for Disease Prevention and Control-this study has co-constructed a consensus-based paradigm aligned with international health research standards. This article outlines its relevance and limitations for public health.Method: Over a two-year period, the study engaged all stakeholders, i.e., more than 1,000 participants. Participatory workshops based on international health research recommendations and experiential knowledge, and consensus sessions were conducted under the guidance of a multidisciplinary committee and with the logistical support of the Non-Pharmacological Intervention Society. These efforts helped to identify the key descriptive and evaluative invariants specific to NPIs. Four phases followed: development, improvement, voting, and consultation.Results: The term NPI refers to prevention or care protocols with a physical, nutritional, or psychosocial focus, targeting a health issue and personalized by a qualified professional. The evaluation framework comprises 77 invariants—14 ethical and 63 methodological—distributed across five types of study: mechanistic, observational, prototypical, interventional, and implementation. The NPIS Model paradigm was endorsed by 31 learned societies and three French health authorities.Conclusion: The term NPI should be reserved for prevention and care protocols that are described, explainable, effective, safe, and implementable. The consensual framework for co-constructed evaluation should promote the transfer of NPIs from research to practice, their interprofessional coordination, contextual adaptation, continuous improvement, training, and, finally, their recognition. This scientific paradigm strengthens the role of public health professionals in developing targeted, efficient, and potentially fundable interventions for at-risk or ill populations. It paves the way for the development of an open registry of intangible health care practices that can be codified, shared, traced, and improved, informed by user feedback. This paradigm does not, however, cover all areas of public health.Introduction : Devant l’absence de consensus sur la définition et l’évaluation des interventions non médicamenteuses (INM) malgré l’utilisation de la notion par l’OMS, la HAS, le ministère de la santé et le Centre européen de prévention et contrôle des maladies par exemple, une étude a co-construit un paradigme consensuel répondant aux standards de la recherche internationale dans le domaine de la santé. L’article présente ses intérêts et ses limites pour la santé publique. Méthode : L’étude a mobilisé durant deux ans toutes les parties prenantes, soit plus de 1000 personnes. Des ateliers participatifs s’appuyant sur les recommandations internationales de la recherche en santé et l’expérience et des sessions de consensus ont été menés sous le pilotage d’un comité pluridisciplinaire et la logistique de la société savante Non-Pharmacological Intervention Society. Ils ont permis d’identifier les invariants descriptifs et évaluatifs spécifiques aux INM. Quatre phases se sont succédé, élaboration, amélioration, vote, consultation. Résultats : Le terme INM désigne des protocoles de prévention ou de soin ayant une dominante corporelle, nutritionnelle ou psychosociale, ciblés sur un problème de santé et personnalisés par un professionnel qualifié. Le cadre d’évaluation comporte 77 invariants, 14 éthiques et 63 méthodologiques. Ces derniers sont répartis en cinq types d’étude : mécanistique, observationnelle, prototypique, interventionnelle et d’implémentation. Le paradigme NPIS Model a reçu le soutien de 31 sociétés savantes et trois autorités de santé françaises. Conclusion : Le terme INM devrait être réservé aux protocoles de prévention et de soin décrits, explicables, efficaces, sûrs et implémentables. Le cadre consensuel d’évaluation co-construit devrait favoriser la transférabilité des INM de la recherche à la pratique, leur coordination pluriprofessionnelle, leur adaptation au contexte, leur amélioration continue, leur formation, et finalement leur reconnaissance. Ce paradigme scientifique renforce le rôle des professionnels de la santé publique dans le développement d’actions ciblées, efficientes, et possiblement finançables au bénéfice des publics à risque ou malades. Il ouvre la voie au développement d’un référentiel en accès libre de pratiques immatérielles de santé codifiables, partageables, traçables et améliorables par la prise en compte des retours d’expérience. Ce paradigme ne couvre en aucun cas tous les domaines de la santé publique
Optimizing delivery of specialized pro-resolving mediators for oral inflammation via smart hydrogels and biomaterials
No full textInternational audienceChronic oral inflammatory diseases such as pulpitis, periodontitis, and peri-implantitis pose significant clinical challenges, often resulting in irreversible tissue loss despite the application of current therapies. Specialized pro-resolving mediators (SPMs) offer a novel therapeutic paradigm by actively promoting the resolution of inflammation and tissue regeneration without compromising host defense. However, the clinical translation of SPMs is hindered by their rapid degradation, low bioavailability, and poor localization to inflamed tissues. Smart biomaterial-based delivery systems, particularly stimuli-responsive hydrogels, have emerged as promising platforms to overcome these barriers. These systems enable controlled, localized, and environment-triggered release of SPMs, enhancing their stability and therapeutic efficacy. Preclinical studies in models of oral inflammation demonstrate that hydrogel-mediated SPM delivery not only resolves inflammation but also preserves tissue structure and promotes regeneration. Future strategies will focus on optimizing dosing protocols, ensuring long-term bioactivity, and addressing regulatory and manufacturing challenges to enable clinical adoption. By enhancing the delivery and sustained bioactivity of SPMs, biomaterial-based strategies have the potential to fundamentally transform the management of oral inflammatory diseases and advance regenerative dental therapies
To be or not to be in the insect flour? My kingdom for a Salmonella!
No full textInternational audienceBackground:Despite the EFSA having assessed Tenebrio molitor larvae (dried yellow mealworm) as a safe edible insect species and having suggested Hermetia illucens (the black soldier fly) as a candidate for human consumption, the effectiveness of reference detection methods for pathogens such as Salmonella spp. is still under evaluation.This study aims to assess the effectiveness of NF EN ISO 6579-1 for Salmonella spp., in insect flour matrixes with particular attention to the enrichment stage and the identification of potential chemical or biological inhibitors.Methods:Two matrices, Tenebrio molitor larvae flour and Hermetia illucens flour, were analyzed for their total flora using MALDI-TOF. For each matrix, ionized and non-ionized flour samples were artificially inoculated with Salmonella using BioMérieux® BioBalls. The evolution of this pathogen in insect flour during enrichment culturing, as well as the potential impact of background flora, was studied using microbiological methods and metagenomics, respectively.Results and discussion:The results highlight the presence of a rich total flora in both flours and differences in the evolution of Salmonella between the two matrices. The ongoing analysis of the results will help determine the effectiveness of the ISO methods used and may contribute to the development of new practices for detecting these two pathogens, which are leading causes of foodborne infections
In situ multiscale characterization of cellulose nanocrystals orthotropic organization achieved by combining ultrasound and frontal ultrafiltration
No full textInternational audienceCombining frontal ultrafiltration (FU) and ultrasound (US) processes, an orthotropic organization of cellulose nanocrystals (CNCs) suspensions was achieved and characterized at multiscale, from the nanometer length scale by small angle X-ray scattering (SAXS) and dichroism, to the micrometer length scale by small angle light scattering (SALS). A dedicated channel cell has been developed to simultaneously generate a vertical acoustic force via a vibrating blade at the top and a transmembrane pressure force through the membrane at the bottom. Three specific orientations in three successive layers were revealed in a one-step FU-US process. In a first layer at the bottom, the CNCs were concentrated under the action of transmembrane pressure with their director aligned parallel to the horizontal membrane surface. In a second upper layer a random orientation of the CNCs was detected. Finally, in the upper part of the channel, a third layer of CNCs with their director vertically oriented was revealed. Near the membrane surface, transmembrane pressure forces dominate, leading to highly concentrated CNCs deposition with enough consistency to avoid any change in orientation induced by the US at the top of the channel. At increasing distances from the membrane, acoustic radiation forces become predominant, reorienting the CNCs vertically
Early excision and sequelae of facial and cervical burns: A matched-cohort study of 110 patients
No full textInternational audienceBackgroundEarly surgical excision of deep burns is a life-saving strategy, but its impact on long-term sequelae, particularly in the cephalic region, remains insufficiently studied. This is a critical concern, as facial and cervical burns often carry significant functional, aesthetic, and psychosocial consequences.MethodsWe conducted a matched observational cohort study comparing adults with deep facial and/or cervical burns who underwent early excision (<10 days post-injury) versus those treated later (≥10 days). A total of 243 patients were screened, and 55 matched pairs were included based on age, sex, burn depth, and total body surface area burned. A sensitivity analysis was performed using a 7-day threshold.ResultsSequelae occurred in 36.4 % of patients in the early excision group versus 33.4 % in the delayed group. The difference was not statistically significant (p = 0.69). The relative risk (RR) of sequelae with early excision was 1.11 (95 % CI: 0.66–1.86). Sensitivity analysis using a 7-day threshold yielded a similar RR of 0.98 (0.56–1.70), indicating no increased risk associated with earlier intervention.ConclusionOur findings suggest that early excision (<10 days) of deep facial and cervical burns in adults does not increase the risk of long-term sequelae. Larger prospective studies are needed to validate these results and further guide clinical practice
Intérêt du dosage de la SDMA (Diméthylarginine Symétrique) dans le diagnostic des affections rénales chez 15 chevaux admis aux CISCO
No full textLes atteintes rénales sont des pathologies difficiles à diagnostiquer précocement chez les chevaux, de nombreux marqueurs existent, mais présentent tous des inconvénients (biais d’interprétation, faisabilité voire technicité de l’analyse, etc.). Un consensus de 2024 évoque l’utilisation de la SDMA en médecine équine, sa supériorité face à la créatinine n’est tout de fois pas suffisamment documentée. L’objectif de cette étude est de savoir si la SDMA peut être un biomarqueur précoce d’une atteinte rénale chez le cheval. Pour cela, une étude rétrospective est réalisée à partir de dossiers de chevaux admis au CISCO et contenant une mesure de la SDMA. Ces chevaux sont dichotomisés en deux groupes principaux : insuffisance rénale aiguë ou maladie rénale chronique. Dans notre étude, le dosage de la SDMA semble intéressant pour identifier des chevaux présentant une insuffisance rénale aiguë alors qu’il est plutôt utilisé pour diagnostiquer les atteintes chroniques chez les animaux de compagnie. Des études restent à faire pour tenter d’identifier un seuil de SDMA permettant de distinguer les animaux sains, de ceux atteints d’insuffisance rénale aiguë ou chronique. Par ailleurs, la précocité du diagnostic n’a pas été établie avec ce dosage. Les résultats obtenus permettent d’ouvrir des pistes pour des recherches à venir avec des effectifs de population plus importants. De nouvelles réponses pourront très prochainement être apportées par une étude internationale sur le sujet de la SDMA chez le cheval, les données utilisées dans cette thèse seront donc incluses à cette étude plus large