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Changes in airway resistance induced by nasal inhalation of cold dry, dry, or moist air in normal individuals 总被引:3,自引:0,他引:3
Fontanari Pierre; Burnet Henri; Zattara-Hartmann Marie Caroline; Jammes Yves 《Journal of applied physiology》1996,81(4):1739-1743
Fontanari, Pierre, Henri Burnet, Marie CarolineZattara-Hartmann, and Yves Jammes. Changes in airway resistanceinduced by nasal inhalation of cold dry, dry, or moist air in normalindividuals. J. Appl. Physiol. 81(4):1739-1743, 1996.Nasopulmonary bronchomotor reflexes elicited bymechanical or irritant stimulation of the nose have been described inanimals and asthmatic patients. However, few studies were devoted tothe consequences of nasal breathing of cold and dry air or of only dryor only moist air on the bronchomotor control in normal individuals.The present study reported changes in interruption resistance (Rint)measured during eupneic breathing of moderately cold (4 or10°C) and dry [0.3% relative humidity (RH)] airor of room air at 23°C that is either dry (0.3% RH) or moist (97%RH). Nasal inhalation of cold (4°C) dry air or of only dryair significantly increased baseline Rint value (17 and 21%,respectively) throughout the 15-min test periods. The response to cold was significantly accentuated when the air temperature was lowered to 10°C (42%). After nasal anesthesia orinhalation of a cholinergic antagonist, cold air did not induce achange in Rint. Nasal inhalation of moist room air had no effect. No Rint changes were measured during oral breathing of the three testagents. It is concluded that the activation of cold receptors orosmoreceptors in the nasal mucosa induces protective bronchoconstrictor responses in normal individuals. 相似文献
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Mitochondria sense and shape cytosolic Ca2+ signals by taking up and subsequently releasing Ca2+ ions during physiological and pathological Ca2+ elevations. Sustained elevations in the mitochondrial matrix Ca2+ concentration are increasingly recognized as a defining feature of the intracellular cascade of lethal events that occur in neurons during cerebral ischemia. Here, we review the recently identified transport proteins that mediate the fluxes of Ca2+ across mitochondria and discuss the implication of the permeability transition pore in decoding the abnormally sustained mitochondrial Ca2+ elevations that occur during cerebral ischemia. 相似文献
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Maurício da Fonseca Maria João Jurak Edita Kataja Kim Master Emma R. Berrin Jean-Guy Stals Ingeborg Desmet Tom Van Landschoot Anita Briers Yves 《Applied microbiology and biotechnology》2018,102(23):10091-10102
Applied Microbiology and Biotechnology - Carbohydrate-active enzyme discovery is often not accompanied by experimental validation, demonstrating the need for techniques to analyze substrate... 相似文献
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Cyril Bories Matthieu J. Guitton Carl Julien Cyntia Tremblay Milène Vandal Meriem Msaid Yves De Koninck Frédéric Calon 《PloS one》2012,7(9)
Besides memory deficits, Alzheimer’s disease (AD) patients suffer from neuropsychiatric symptoms, including alterations in social interactions, which are subject of a growing number of investigations in transgenic models of AD. Yet the biological mechanisms underlying these behavioural alterations are poorly understood. Here, a social interaction paradigm was used to assess social dysfunction in the triple-transgenic mouse model of AD (3xTg-AD). We observed that transgenic mice displayed dimorphic behavioural abnormalities at different ages. Social disinhibition was observed in 18 months old 3xTg-AD males compared to age and sex-matched control mice. In 3xTg-AD females, social disinhibition was present at 12 months followed by reduced social interactions at 18 months. These dimorphic behavioural alterations were not associated with alterations in AD neuropathological markers such as Aβ or tau levels in the frontal cortex. However, patch-clamp recordings revealed that enhanced social interactions coincided temporally with an increase in both excitatory and inhibitory basal synaptic inputs to layer 2–3 pyramidal neurons in the prefrontal cortex. These findings uncover a novel pattern of occurrence of psychiatric-like symptoms between sexes in an AD model. Our results also reveal that functional alterations in synapse activity appear as a potentially significant substrate underlying behavioural correlates of AD. 相似文献
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Fe homeostasis in plant cells: Does nicotianamine play multiple roles in the regulation of cytoplasmic Fe concentration? 总被引:14,自引:0,他引:14
Axel Pich Renate Manteuffel Stefan Hillmer Günter Scholz Wolfgang Schmidt 《Planta》2001,213(6):967-976
The cellular and intracellular localization of the non-proteogenic amino acid nicotianamine (NA) in leaves and root elongation zones was immunochemically investigated in pea (Pisum sativum L.) and tomato (Lycopersicon esculentum Mill.) plants grown under various iron regimes and in three mutants defective in the regulation of iron uptake. Strongest immunostaining was observed in the over-accumulating pea mutants brz and dgl, and in iron-loaded wild-type plants. Fe concentration and NA level paralleled staining intensity, indicating that NA synthesis is induced by high iron availability. While label was mainly present in the cytoplasm under normal (10 microM) Fe supply and under Fe deprivation, most of the labeling was present in the vacuole in iron-loaded plants. This pattern resembled the distribution of NA in Fe over-accumulating mutants, indicating the possible importance of vacuolar sequestration in the detoxification of excess Fe. Based on the dependence of the cellular distribution of NA on the iron nutritional status of the plant, a possible role of NA in buffering free Fe in root and leaf cells was inferred. We show here for the first time that the NA concentration is increased in response to iron overload, indicating that, besides other classes of intracellular metal-binding ligands, NA may play an essential role in iron tolerance. 相似文献
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