H. Gautier

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The interaction between the pulmonary afferents (PA) and the pneumotaxic center (PC) in control of respiratory pattern was studied in lightly anesthetized paralyzed cats before and after bivagotomy or lesions of the PC using inflations controlled by the onset or cessation of phrenic nerve discharge, i.e., cycle-triggered inflations. This interaction was(More)
Understanding how the fruit microclimate affects ascorbate (AsA) biosynthesis, oxidation and recycling is a great challenge in improving fruit nutritional quality. For this purpose, tomatoes at breaker stage were harvested and placed in controlled environment conditions at different temperatures (12, 17, 23, 27 and 31 °C) and irradiance regimes (darkness or(More)
The objective of this work was to construct a model of aerial development of clover that takes into account morphogenetic responses to the light environment, and to use it to analyse and understand these processes in terms of signal perception and integration. The plant model was interfaced with a Monte Carlo model that determines photosynthetically active(More)
The fruit is a hierarchically organized organ composed of cells from different tissues. Its quality, defined by traits such as fruit size and composition, is the result of a complex chain of biological processes. These processes involve exchanges (transpiration, respiration, photosynthesis, phloem and xylem fluxes, and ethylene emission) between the fruit(More)
Little is known about the light regulation of vitamin C synthesis in fruits. In contrast, previous studies in leaves revealed that VTC2 (coding for GDP-l-galactose phosphorylase) was one of the key genes up-regulated by light in leaves. Our objective was to determine how the expression of ascorbate (AsA) synthesis genes in tomato (Solanum lycopersicum) was(More)
Dimethyl disulfide (DMDS), a plant-derived insecticide, is a promising fumigant as a substitute for methyl bromide. To further understand the mode of action of DMDS, we examined its effect on cockroach octopaminergic neurosecretory cells, called dorsal unpaired median (DUM) neurons, using whole-cell patch-clamp technique, calcium imaging and antisense(More)
Using whole cell patch-clamp technique and immunocytochemistry on adult dorsal unpaired median (DUM) neurons isolated from the cockroach Periplaneta americana CNS, we reported the characterization of a native mGluR, sharing pharmacological properties with vertebrate metabotropic glutamate receptor III (mGluRIII) that regulated voltage-dependent sodium(More)
The crop sensitivity to ozone (O3) is affected by the timing of the O3 exposure, by the O3 concentration, and by the crop age. To determine the physiological response to the acute ozone stress, tomato plants were exposed to O3 at two growth stages. In Experiment I (Exp. I), O3 (500 μg m−3) was applied to 30-d-old plants (PL30). In Experiment II (Exp. II),(More)
The metabolic state is one of the determinants of the general activity level. Satiety is related to resting or sleep whereas hunger correlates to wakefulness and activity. The counterpart to the mammalian satiety signal cholecystokinin (CCK) in insects are the sulfakinins. The aim of this study was to resolve the mechanism by which the antifeedant activity(More)
Reducing the use of pesticides represents a major challenge of modern agriculture. Plants synthesize secondary metabolites such as polyphenols that participate in the resistance to parasites. The aim of this study was to test: (1) the impact of nitrogen deficiency on tomato (Solanum lycopersicum) leaf composition and more particularly on two phenolic(More)