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Estrogenic Compounds or Adiponectin Inhibit Cyclic AMP Response to Human Luteinizing Hormone in Mouse Leydig Tumor Cells
No full textMouse Leydig Tumor cells (mLTC), transiently expressing cAMP-dependent luciferase, were used to study the influence of sexual steroids and of adiponectin (ADPN) on the cAMP response to luteinizing hormones (LH). While testosterone and progesterone had no significant effect, several molecules with estrogenic activity (17 beta -estradiol, ethynylestradiol, and bisphenol A) provoked a decrease in intracellular cyclic AMP accumulation under 0.7 nM human LH stimulation. Adiponectin exhibited a bimodal dose-effect on LH response: synergistic between 2-125 ng/mL and inhibitory between 0.5-5 mu g/mL. In brief, our data indicate that estrogens and ADPN separately exert rapid (<1 h) inhibitory and/or synergistic effects on cAMP response to LH in mLTC-1 cells. As the inhibitory effect of each estrogenic molecule was observed after only 1-h preincubation, it might be mediated through the G protein-coupled estrogen receptor (GPER) membrane receptor, but this remains to be demonstrated. The synergistic effect with low concentrations of ADPN with human Luteinizing Hormone (hLH) was observed with both fresh and frozen/thawed ADPN. In contrast, the inhibitory effect with high concentrations of ADPN was lost with frozen/thawed ADPN, suggesting deterioration of its polymeric structure
Variations of the stem diameter as an indicator of plant mortality under extreme drought in lavender
No full textContinuous measurement for stem diameter variations allows to monitor the phenology, growth dynamic and related-physiology of plants. During a drought event, the decrease in stem diameter is due to a loss of water balance, mainly detected in the non-rigid bark. We have used a dedicated device (PepiPIAF system, Hydrasol) to monitor the response to extreme drought of lavender (Lavandula angustifolia). Lavender is a crop living under very dry conditions (Mediterranean biome) and barely studied. During a dehydration-rehydration experiment, physiological parameters such as water potential, stomatal and hydraulic conductances, cell damages and ultrasonic acoustic activity, were continuously monitored in relation with stem diameter. Our results highlight the dehydration threshold (as a ratio of diameter loss) that significantly affect the resilience to drought and related mortality. We therefore developed a mortality index based on stem diameter monitoring that could help to anticipate lavander death. Based on the common mechanisms affecting plant, it should apply to many different species
Aerobic fermentation prior to pasteurization produces a selective substrate for cultivation of the mushroom Pleurotus pulmonarius
No full textDescription of the subject. Pleurotus species are cultivated on lignocellulosic substrates, in which contaminant fungi such as Trichoderma spp. are common. A selective substrate for Pleurotus provides the necessary conditions for protection against contaminants. Studies show that Paenibacillus polymyxa and other thermophilic bacteria benefit from the selectivity of Pleurotus cultivation substrate, however, little is known regarding these bacterial communities.[br/]
Objectives. To evaluate the effect of substrate inoculation with Paenibacillus polymyxa on the productivity of Pleurotus pulmonarius and its protection against Trichoderma.[br/]
Method. Barley straw inoculated with P. polymyxa and non-inoculated straw (control) was used following 0, 3 or 5 days of fermentation prior to heat treatment in order to produce the cultivation substrate. The microbiological content before and after the heat treatment, the mycelial colonization by P. pulmonarius and Trichoderma viride in competition and the yield of P. pulmonarius were all evaluated.[br/]
Results. We observed that inoculation with P. polymyxa increased the number of cultivable bacteria and changed the composition of the community. The inoculation decreased the colonization ability of T. viride and favored the mycelial growth, although the yield of mushrooms was affected. Higher yields of P. pulmomarius were obtained in the control substrate where no contamination of Trichoderma spp. was observed.[br/]
Conclusions. Addition of P. polymyxa modified the natural microbiological succession in a fermentation of barley straw for 5 days, favoring the competitiveness of P. pulmonarius against T. viride. Fermentation of barley straw for 3 days, followed by heat treatment, benefits the yield and protection of P. pulmonarius against Trichoderma viride.Description du sujet. Les espèces de Pleurotus sont cultivées sur des substrats lignocellulosiques, où des champignons contaminants tels que Trichoderma spp. sont communs. Un substrat sélectif pour Pleurotus doit fournir les conditions nécessaires à la protection contre les contaminants. Des études ont montré que Paenobacillus polymyxa et d'autres bactéries thermophiles peuvent participer à la sélectivité du substrat de culture pour Pleurotus, mais on sait peu de choses sur les communautés bactériennes impliquées dans ces différents substrats.[br/]
Objectifs. Évaluer l'effet de l'inoculation de P. polymyxa dans un substrat de culture sur la productivité de P. pulmonarius et sur la protection contre Trichoderma.[br/]
Méthode. De la paille d'orge inoculée avec P. polymyxa et de la paille non inoculée (témoin) ont été utilisées après 0, 3 ou 5 jours de fermentation avant un traitement thermique pour produire le substrat de culture. Le contenu microbiologique avant et après traitement thermique, la colonisation mycélienne par P. pulmonarius et Trichoderma viride en compétition et le rendement de P. pulmonarius ont été évalués.[br/]
Résultats. Nous avons observé que l'inoculation avec P. polymyxa augmentait le nombre de bactéries cultivables et modifiait la composition de la communauté microbienne. Elle diminue la capacité de colonisation de T. viride et favorise la croissance mycélienne. Cependant, le rendement en champignons a été affecté. Les rendements plus élevés de P. pulmonarius ont été obtenus dans le substrat témoin où aucune contamination de Trichoderma spp. n’a été observée.[br/]
Conclusions. L'ajout de P. polymyxa a modifié la succession microbiologique naturelle lors d’une fermentation de paille d'orge pendant 5 jours, favorisant la compétitivité de P. pulmonarius par rapport à T. viride. La fermentation de la paille d'orge pendant les 3 jours qui suivent un traitement thermique est bénéfique pour le rendement et la protection de P. pulmonarius contre T. viride
Profiling the temperature dependent frequency of an open-magnet for outdoor applications
No full textCaractérisation du comportement d’ingestion solide chez le lape-reau d’élevage et évaluation des conséquences sur la santé
No full textUtilisation de l’Eci pour la transparisation chez le poisson : exemples d’applications pour l’imagerie 3D
No full textGreen bio-assisted synthesis, characterization and biological evaluation of biocompatible ZnO NPs synthesized from different tissues of milk thistle (Silybum marianum)
No full textThe purpose of the current study was green synthesis of ZnO-nanoparticles (NPs) from different tissues of Silybum marianum (L.) Gaernt. (i.e., seeds, wild plant, in vitro derived plantlets and callus cultures) followed by extensive characterization and evaluation of their biological potency. ZnO-NPs thus synthesized were subjected to characterization using standard techniques such as XRD, FTIR and SEM. Thermal stability of synthesized NPs was also evaluated using thermo-gravimetric analysis. Highly stable crystalline NPs with size ranging between 30.8 and 46.0 nm were obtained from different tissues of S. marianum. These NPs have revealed a wide range of biological applications showing antioxidant, moderate α-amylase inhibitor, antibacterial and cytotoxic potencies. The highest antibacterial activity (20 ± 0.98 mm) was shown by seed extract-mediated ZnO NPs against Staphylococcus aureus (ATCC-6538). Seed extract-mediated ZnO NPs also showed the most potent antioxidant activity (27.7 ± 0.9 µgAAE/mg, 23.8 ± 0.7 µgAAE/mg and 12.7 ± 1.9% total antioxidant capacity (TAC), total reducing power (TRP) and DPPH-free radical scavenging assay (FRSA), respectively). All of the synthesized ZnO NPs also showed cytotoxic activity against the hepato-cellular carcinoma (HepG2) human cells. Interestingly, these ZnO NPs were also highly biocompatible, as evidenced by the brine shrimp lethality and human red blood cells hemolytic assays. Among all of the NPs synthesized and used, the effect of seed extract-mediated NPs was found to be most promising for future applications
La période preimplantatoire du développement des mammifères: la souris est-elle un bon modèle?
No full textMeasuring the Economic, Environmental, and Social Sustainability of Short Food Supply Chains
No full textThe production and distribution of food are among the hot topics debated in the context
of sustainable development. Short food supply chains (SFSCs) are now widely believed to be more
sustainable in comparison to mass food delivery systems. To date, very little quantitative evidence
exists on the impacts of various types of food supply chains. Using a cross-sectional quantitative
approach, this study assesses the sustainability of distribution channels in short and long food supply
chains based on 208 food producers across seven countries: France, Hungary, Italy, Norway, Poland,
the United Kingdom, and Vietnam. Ten distribution channel types are used in this study. To provide
a comprehensive sustainability assessment, a set of economic, social, and environmental indicators
are applied. Indicators commonly used in the literature are used, supported by original indicators
constructed specifically for the present study. In total, 486 chains are examined and the study confirms
that individual producers participate simultaneously in several, short and long chains. Participation
in SFSCs is beneficial for producers from an economic perspective. SFSCs allow producers to capture
a large proportion of margin otherwise absorbed by di erent intermediaries. It appears, however,
that ’longer’ supply channels generate lower environmental impacts per unit of production when
measured in terms of food miles and carbon footprint. Finally, ambiguous results are found regarding
social dimension, with significant di erences across types of chains