Variation in physiological host range in three strains of two species of the entomopathogenic fungus Beauveria

Knowledge of the host range of a biocontrol agent (BCA) is fundamental. Host range determines the BCA's economic potential, as well as the possible risk for non-target organisms. Entomopathogenic fungal strains belonging to the genus Beauveria are widely used as BCA, but our knowledge of their physiological host range is only partial. The aim of this study was to improve our understanding of the physiological host range of three Beauveria strains belonging to two species, B. hoplocheli and B. bassiana. We performed laboratory mortality bioassays to assess their pathogenicity and virulence against nine insect pests, belonging to three orders: Lepidoptera, Coleoptera and Diptera. Mortality rate, mean survival time and mycosis rate were used to estimate virulence. Pathogenicity was assessed as the capacity to cause a disease and induce mortality. Virulence was assessed as the severity of the disease based on mortality rate, mean survival time and mycosis rate. The results of this study revealed significant differences in the physiological host range of the three Beauveria strains tested. The three strains were pathogenic to all Diptera and Lepidoptera species tested. In the case of the Coleoptera, only the B. hoplocheli strain was pathogenic to the white grub Hoplochelus marginalis and only the B. bassiana strains were pathogenic to Alphitobius diaperinus. The B. hoplocheli strain was less virulent on Lepidoptera and Diptera than the two B. bassiana strains. The latter both exhibited very similar virulence patterns. The fact that B. hoplocheli and B. bassiana strains have different host ranges means that they can be used as BCA to target different pests. Impacts on non-target insects across multiple orders cannot be ruled out in the absence of ecological host range studies

Prendre le terrain pour objet : une expérience de recherche collective sur les espaces publics à Ibadan, Nigeria

Cet article s’appuie sur la réalisation de brefs terrains collectifs dans différents espaces publics de la ville d’Ibadan au Nigeria. Il propose une réflexion sur l’insertion de jeunes étudiantes blanches occidentales dans ces espaces publics ainsi que dans les groupes de recherche concernés. Nous souhaitons comprendre dans quelle mesure notre positionnement a pu se révéler contraignant tout en nous renseignant sur les terrains étudiés.This article relies on short field works realized in different public spaces in the city of Ibadan, Nigeria. It provides a reflection on young Western white female students’ integration in these public spaces and in their research groups. We try to understand to what extent our position may have been both restrictive and useful for the understanding of our fieldworks

Field trials design to assess sugar beet varieties resistance to Rhizoctonia solani : results from the R2B project

National audienc

Effect of Point Spread Function Deconvolution in Reconstruction of Brain 18F-FDG PET Images on the Diagnostic Thinking Efficacy in Alzheimer's Disease

Purpose: This study aims to determine the effect of applying Point Spread Function (PSF) deconvolution, which is known to improve contrast and spatial resolution in brain 18F-FDG PET images, to the diagnostic thinking efficacy in Alzheimer's disease (AD).Methods: We compared Hoffman 3-D brain phantom images reconstructed with or without PSF. The effect of PSF deconvolution on AD diagnostic clinical performance was determined from digital brain 18F-FDG PET images of AD (n = 38) and healthy (n = 35) subjects compared to controls (n = 36). Performances were assessed with SPM at the group level (p < 0.001 for the voxel) and at the individual level by visual interpretation of SPM T-maps (p < 0.005 for the voxel) by the consensual analysis of three experienced raters.Results: A mix of large hypometabolic (1,483cm3, mean value of −867 ± 492 Bq/ml) and intense hypermetabolic (902 cm3, mean value of 1,623 ± 1,242 Bq/ml) areas was observed in the PSF compared to the no PSF phantom images. Significant hypometabolic areas were observed in the AD group compared to the controls, for reconstructions with and without PSF (respectively 23.7 and 26.2 cm3), whereas no significant hypometabolic areas were observed when comparing the group of healthy subjects to the control group. At the individual level, no significant differences in diagnostic performances for discriminating AD were observed visually (sensitivity of 89 and 92% for reconstructions with and without PSF respectively, similar specificity of 74%).Conclusion: Diagnostic thinking efficacy performances for diagnosing AD are similar for 18F-FDG PET images reconstructed with or without PSF

Brain 18F-FDG PET for the diagnosis of autoimmune encephalitis: a systematic review and a meta-analysis

International audienc

High-quality brain perfusion SPECT images may be achieved with a high-speed recording using 360° CZT camera

International audienceAbstract Objective The aim of this study was to compare brain perfusion SPECT obtained from a 360° CZT and a conventional Anger camera. Methods The 360° CZT camera utilizing a brain configuration, with 12 detectors surrounding the head, was compared to a 2-head Anger camera for count sensitivity and image quality on 30-min SPECT recordings from a brain phantom and from 99m Tc-HMPAO brain perfusion in 2 groups of 21 patients investigated with the CZT and Anger cameras, respectively. Image reconstruction was adjusted according to image contrast for each camera. Results The CZT camera provided more than 2-fold increase in count sensitivity, as compared with the Anger camera, as well as (1) lower sharpness indexes, giving evidence of higher spatial resolution, for both peripheral/central brain structures, with respective median values of 5.2%/3.7% versus 2.4%/1.9% for CZT and Anger camera respectively in patients ( p < 0.01), and 8.0%/6.9% versus 6.2%/3.7% on phantom; and (2) higher gray/white matter contrast on peripheral/central structures, with respective ratio median values of 1.56/1.35 versus 1.11/1.20 for CZT and Anger camera respectively in patients ( p < 0.05), and 2.57/2.17 versus 1.40/1.12 on phantom; and (3) no change in noise level. Image quality, scored visually by experienced physicians, was also significantly higher on CZT than on the Anger camera (+ 80%, p < 0.01), and all these results were unchanged on the CZT images obtained with only a 15 min recording time. Conclusion The 360° CZT camera provides brain perfusion images of much higher quality than a conventional Anger camera, even with high-speed recordings, thus demonstrating the potential for repositioning brain perfusion SPECT to the forefront of brain imaging

A clear trade-off exists between the theoretical efficiency and acceptability of dietary changes that improve nutrient adequacy during early pregnancy in French women: Combined data from simulated changes modeling and online assessment survey

International audienceBackgroundDuring pregnancy, the diet of a mother-to-be should be adapted to meet increases in nutrient requirements. We analyzed the theoretical efficiency and acceptability of different types of tailored dietary changes for pregnant women.MethodsThe nutrient adequacy of the diet was evaluated using the PANDiet score, by comparing the nutrient intakes of 344 non-pregnant premenopausal women (18–44y) with dietary reference intakes for the first trimester of pregnancy. Simulations were performed to evaluate the theoretical efficiency of three types of ten successive tailored dietary changes in improving nutrient adequacy, with graded difficulty in implementation. The acceptability (declared intention to use in the diet) of most efficient dietary changes was evaluated during an online randomized study including 115 French pregnant women (22–41y).ResultsModifying the amount consumed of foods (type-1) did not modify the food repertoire and resulted in the smallest theoretical efficiency (increase in the PANDiet score of 9.8±0.2 points), but changes were the most acceptable (probability of the intention to use: 0.30–0.78). Conversely, replacing food items by items from the same group or eaten at the same time (type-3) broadened the food repertoire (3.6±1.3 food subgroups added) and resulted in the greatest theoretical efficiency (+23.9±0.3) but changes were the least acceptable (0.07–0.23). Replacing food items within the same subgroup (type-2) slightly broadened the food repertoire (+8.0±1.3 foods) and resulted in moderate theoretical efficiency (+14.8±0.2) and intermediate acceptability (0.11–0.35).ConclusionA clear trade-off exists between the theoretical efficiency and acceptability of dietary changes, with a graded broadening of the food repertoire

From metabolic connectivity to molecular connectivity: application to dopaminergic pathways

International audienc

Les conseils alimentaires personnalisés améliorant le plus efficacement l'adéquation nutritionnelle des régimes en début de grossesse sont les moins acceptables

International audienceIntroduction et but de l’étude : La grossesse s’accompagne d’une augmentation de la plupart des besoins nutritionnelsqui nécessite une adaptation du régime alimentaire. Les femmes enceintes seraient particulièrement enclines à l’adoptionde comportements alimentaires plus sains. Cette période représente donc une fenêtre d’opportunité pour proposer desinterventions diététiques permettant d’améliorer les apports nutritionnels usuels. Cependant, afin d’en maximiserl’efficacité nutritionnelle, les changements alimentaires proposés doivent être acceptables par les femmes enceintes.L’objectif de cette étude était d’évaluer de manière croisée l’efficacité nutritionnelle et l’acceptabilité de différents types deconseils alimentaires personnalisés pour les femmes enceintes.Matériel et méthodes : Pour trois types de conseils alimentaires personnalisés (modification des quantités consommées(type 1), substitutions au sein d’un même sous-groupe d’aliments (type 2), ou au sein d’un même groupe ou moment deconsommation (type 3)), l’efficacité théorique a été définie comme la capacité à améliorer l’adéquation nutritionnelle durégime alimentaire mesurée par le score de PANDiet adapté aux besoins nutritionnels du 1er trimestre de grossesse, et aété évaluée par simulation à partir des consommations de 344 femmes en âge de procréer (18–44 ans) ayant participé àl’Étude Nationale Nutrition Santé (ENNS). Pour 29 conseils sélectionnés parmi les 60 les plus fréquemment identifiés,l'acceptabilité des conseils a été définie comme la potentielle intention d’usage dans le régime et a été évaluée lors d’uneenquête longitudinale en ligne incluant 115 femmes enceintes. Des modèles mixtes de régression logistique ont étéutilisés pour estimer la probabilité d’intention d’usage des conseils. L’association entre l’efficacité (gain moyen de pointsde PANDiet sur l’ensemble des simulations) et l’acceptabilité (probabilité d’intention d’usage) de chaque conseil a étéévaluée à l’aide d’une régression linéaire avec transformation inverse de l’efficacité.Résultats et Analyse statistique : L’efficacité théorique moyenne des conseils de type 1 qui ont été évalués est compriseentre 0,65 et 1,47 (points sur 100), celle des conseils de type 2 entre 1,04 et 3,30 et celle des conseils de type 3 entre1,88 et 3,68. Les conseils entraînant l’ouverture du répertoire alimentaire la plus importante sont donc les plus efficaces.Les conseils de type 3 ont été évalués comme les moins acceptables par les femmes enceintes (probabilité d’intentiond’usage comprise entre 0,07 et 0,23), suivis de ceux de type 2 (entre 0,11 et 0,35) puis de type 1 (entre 0,30 et 0,78). Ilexiste une association entre l’acceptabilité et l’inverse de l’efficacité des conseils alimentaires (R²=0,54, P<0,01).Conclusion : Les types de conseils alimentaires qui entraînent les modifications du régime alimentaire les plusimportantes sont les plus efficaces mais aussi les moins acceptables par les femmes enceintes. Explorer les compromisentre efficacité théorique et acceptabilité s’avère important pour prévoir la formulation de recommandations diététiquesappliquées, dont l’efficacité réelle devra être testée en pratique

Combination between the simulation & optimization study and the acceptability study.

<p>Type-1 dietary changes consist in modifying the amount of a food item present in the observed diet (D0’). Type-2 dietary changes consist in replacing a food item consumed in the observed diet (D0’) by a food item from the same subgroup. Selection of food items to be used as potential substitutes under type-2 dietary changes was made to account for their consumption in the French population, their price and their seasonality. Type-3 dietary changes consist in replacing a food item consumed in the observed diet (D0’) by a food item from the same group or that could be consumed at the same time according to the French cultural meal scheme. For the simulation & optimization study (upper part), a step by step optimization process of each individual diet according to each type of changes was used, and this resulted in evaluating the efficiency of each type of changes and identifying the 20 most efficient changes of each type. In the acceptability study, each individual tested in total, 18 different dietary changes (6 of the most efficient of each type), that were divided into 3 sets composed by 6 dietary changes (two by type). Sets A, B and C were presented at three different occasions and each of the 18 changes was evaluated both a priori and a posteriori. Individuals were randomized in 3 groups (#1–3) for the order of evaluation of the 3 sets for the three occasions, according to a Latin square.</p