135 research outputs found

    Phenolic compounds of Galega Vulgar and Cobrançosa olive oils along early ripening stages

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    In this study, the lipophilic and hydrophilic phenol composition of virgin olive oils (VOO) obtained from olives from two of the most important Portuguese cultivars (‘Galega Vulgar’ and ‘Cobrançosa’), harvested at different ripening stages and under two irrigation schemes (rain fed and irrigated), was evaluated. Phenolic alcohols (hydroxytyrosol and tyrosol), phenolic acids and derivatives and flavonoids (luteolin and apigenin), as well as tocopherols were quantified. Lipophilic (>300 mg kg 1) and hydrophilic phenols (>600 mg kg 1) were present in high contents in both VOO, for early ripening stages. Gamma-tocopherol content is higher in ‘Galega Vulgar’ VOO. Total phenols showed a decrease between ripening index 2.5 and 3.5. The dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA), also known as oleacein, was the major phenolic compound identified in both oils. The concentration of free hydroxytyrosol and tyrosol in both VOO is very low while their esterified derivatives, like 3,4-DHPEA-EDA and p- HPEA-EDA, are much more abundantinfo:eu-repo/semantics/publishedVersio

    A TRPA1-dependent mechanism for the pungent sensation of weak acids

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    Acetic acid produces an irritating sensation that can be attributed to activation of nociceptors within the trigeminal ganglion that innervate the nasal or oral cavities. These sensory neurons sense a diverse array of noxious agents in the environment, allowing animals to actively avoid tissue damage. Although receptor mechanisms have been identified for many noxious chemicals, the mechanisms by which animals detect weak acids, such as acetic acid, are less well understood. Weak acids are only partially dissociated at neutral pH and, as such, some can cross the cell membrane, acidifying the cell cytosol. The nociceptor ion channel TRPA1 is activated by CO2, through gating of the channel by intracellular protons, making it a candidate to more generally mediate sensory responses to weak acids. To test this possibility, we measured responses to weak acids from heterologously expressed TRPA1 channels and trigeminal neurons with patch clamp recording and Ca2+ microfluorometry. Our results show that heterologously expressed TRPA1 currents can be induced by a series of weak organic acids, including acetic, propionic, formic, and lactic acid, but not by strong acids. Notably, the degree of channel activation was predicted by the degree of intracellular acidification produced by each acid, suggesting that intracellular protons are the proximate stimulus that gates the channel. Responses to weak acids produced a Ca2+-independent inactivation that precluded further activation by weak acids or reactive chemicals, whereas preactivation by reactive electrophiles sensitized TRPA1 channels to weak acids. Importantly, responses of trigeminal neurons to weak acids were highly overrepresented in the subpopulation of TRPA1-expressing neurons and were severely reduced in neurons from TRPA1 knockout mice. We conclude that TRPA1 is a general sensor for weak acids that produce intracellular acidification and suggest that it functions within the pain pathway to mediate sensitivity to cellular acidosis

    Trigeminal Chemesthesis

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    In the present chapter we will summarize some important functional properties of the human trigeminal chemosensory system in the nasal, ocular and oral mucosae. Among others, we will address issues related to candidate molecular receptors for trigeminal chemesthesis, chemesthetic sensitivity (i.e., detection thresholds), structure-activity relationships, detection of chemical mixtures, and temporal properties of trigeminal chemesthetic sensations

    TRP Channels: Their Function and Potentiality as Drug Targets

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    Fonctionnement de la mémoire autobiographique dans un contexte de traumatisme psychique

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    Psychological trauma defines the emotional shock experienced by an individual following a traumatic event. In some cases, the psychotraumatic symptomatology develops and persists, leading to the onset of posttraumatic stress disorder. The literature has widely described the memory impairment associated with the disease, especially dysfunction of autobiographical memory. This complex memory system contains the story of our past, on which our present identity and future aspirations are based. However, it remains unclear whether this deficit is due to premorbid autobiographical memory dysfunction, to the trauma exposure itself, or to the subsequent development of posttraumatic stress disorder symptomatology. Research has not yet clarified the relationship between autobiographical memory dysfunction and psychological trauma. Throughout this work, we will define autobiographical memory function in the context of psychological trauma. The first two studies will analyze autobiographical memory function following a single traumatic exposure and following repeated exposures. The final study will shed light on how autobiographical memory functions among participants with posttraumatic stress disorder in partial remission.Le traumatisme psychique dĂ©finit le choc Ă©motionnel d'un individu Ă  la suite Ă  d'un Ă©vĂšnement traumatique. Dans certains cas, la symptomatologie psychotraumatique s'installe et perdure entrainant l'apparition d'un Trouble de Stress Post Traumatique. La littĂ©rature dĂ©crit amplement les dĂ©sordres mnĂ©siques qui accompagnent la maladie et notamment l'altĂ©ration de la mĂ©moire autobiographique. Ce systĂšme de mĂ©moire complexe renferme l'histoire de notre passĂ© sur laquelle s'appuie notre individualitĂ© prĂ©sente et nos aspirations futures. Cependant, l'origine du dysfonctionnement de la mĂ©moire autobiographique reste confuse, cette altĂ©ration pourrait ĂȘtre un facteur prĂ©morbide, la consĂ©quence de l'exposition traumatique ou celle de la maladie. Les recherches restent incertaines sur les relations existantes entre le dysfonctionnement de la mĂ©moire autobiographique et le traumatisme psychique. Tout au long de ce travail, nous caractĂ©riserons le fonctionnement de la mĂ©moire autobiographique dans le contexte d'un traumatisme psychique. Les deux premiĂšres Ă©tudes permettront d'analyser la mĂ©moire autobiographique suite Ă  une exposition traumatique unique et suite Ă  des expositions rĂ©pĂ©tĂ©es. La derniĂšre Ă©tude nous Ă©clairera sur le fonctionnement de la mĂ©moire autobiographique chez des sujets en rĂ©mission partielle d'un trouble de stress post traumatique

    Autobiographical memory functioning in a context of psychological trauma

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    Le traumatisme psychique dĂ©finit le choc Ă©motionnel d'un individu Ă  la suite Ă  d'un Ă©vĂšnement traumatique. Dans certains cas, la symptomatologie psychotraumatique s'installe et perdure entrainant l'apparition d'un Trouble de Stress Post Traumatique. La littĂ©rature dĂ©crit amplement les dĂ©sordres mnĂ©siques qui accompagnent la maladie et notamment l'altĂ©ration de la mĂ©moire autobiographique. Ce systĂšme de mĂ©moire complexe renferme l'histoire de notre passĂ© sur laquelle s'appuie notre individualitĂ© prĂ©sente et nos aspirations futures. Cependant, l'origine du dysfonctionnement de la mĂ©moire autobiographique reste confuse, cette altĂ©ration pourrait ĂȘtre un facteur prĂ©morbide, la consĂ©quence de l'exposition traumatique ou celle de la maladie. Les recherches restent incertaines sur les relations existantes entre le dysfonctionnement de la mĂ©moire autobiographique et le traumatisme psychique. Tout au long de ce travail, nous caractĂ©riserons le fonctionnement de la mĂ©moire autobiographique dans le contexte d'un traumatisme psychique. Les deux premiĂšres Ă©tudes permettront d'analyser la mĂ©moire autobiographique suite Ă  une exposition traumatique unique et suite Ă  des expositions rĂ©pĂ©tĂ©es. La derniĂšre Ă©tude nous Ă©clairera sur le fonctionnement de la mĂ©moire autobiographique chez des sujets en rĂ©mission partielle d'un trouble de stress post traumatique.Psychological trauma defines the emotional shock experienced by an individual following a traumatic event. In some cases, the psychotraumatic symptomatology develops and persists, leading to the onset of posttraumatic stress disorder. The literature has widely described the memory impairment associated with the disease, especially dysfunction of autobiographical memory. This complex memory system contains the story of our past, on which our present identity and future aspirations are based. However, it remains unclear whether this deficit is due to premorbid autobiographical memory dysfunction, to the trauma exposure itself, or to the subsequent development of posttraumatic stress disorder symptomatology. Research has not yet clarified the relationship between autobiographical memory dysfunction and psychological trauma. Throughout this work, we will define autobiographical memory function in the context of psychological trauma. The first two studies will analyze autobiographical memory function following a single traumatic exposure and following repeated exposures. The final study will shed light on how autobiographical memory functions among participants with posttraumatic stress disorder in partial remission

    Fonctionnement de la mémoire autobiographique dans un contexte de traumatisme psychique

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    Psychological trauma defines the emotional shock experienced by an individual following a traumatic event. In some cases, the psychotraumatic symptomatology develops and persists, leading to the onset of posttraumatic stress disorder. The literature has widely described the memory impairment associated with the disease, especially dysfunction of autobiographical memory. This complex memory system contains the story of our past, on which our present identity and future aspirations are based. However, it remains unclear whether this deficit is due to premorbid autobiographical memory dysfunction, to the trauma exposure itself, or to the subsequent development of posttraumatic stress disorder symptomatology. Research has not yet clarified the relationship between autobiographical memory dysfunction and psychological trauma. Throughout this work, we will define autobiographical memory function in the context of psychological trauma. The first two studies will analyze autobiographical memory function following a single traumatic exposure and following repeated exposures. The final study will shed light on how autobiographical memory functions among participants with posttraumatic stress disorder in partial remission.Le traumatisme psychique dĂ©finit le choc Ă©motionnel d'un individu Ă  la suite Ă  d'un Ă©vĂšnement traumatique. Dans certains cas, la symptomatologie psychotraumatique s'installe et perdure entrainant l'apparition d'un Trouble de Stress Post Traumatique. La littĂ©rature dĂ©crit amplement les dĂ©sordres mnĂ©siques qui accompagnent la maladie et notamment l'altĂ©ration de la mĂ©moire autobiographique. Ce systĂšme de mĂ©moire complexe renferme l'histoire de notre passĂ© sur laquelle s'appuie notre individualitĂ© prĂ©sente et nos aspirations futures. Cependant, l'origine du dysfonctionnement de la mĂ©moire autobiographique reste confuse, cette altĂ©ration pourrait ĂȘtre un facteur prĂ©morbide, la consĂ©quence de l'exposition traumatique ou celle de la maladie. Les recherches restent incertaines sur les relations existantes entre le dysfonctionnement de la mĂ©moire autobiographique et le traumatisme psychique. Tout au long de ce travail, nous caractĂ©riserons le fonctionnement de la mĂ©moire autobiographique dans le contexte d'un traumatisme psychique. Les deux premiĂšres Ă©tudes permettront d'analyser la mĂ©moire autobiographique suite Ă  une exposition traumatique unique et suite Ă  des expositions rĂ©pĂ©tĂ©es. La derniĂšre Ă©tude nous Ă©clairera sur le fonctionnement de la mĂ©moire autobiographique chez des sujets en rĂ©mission partielle d'un trouble de stress post traumatique

    Fonctionnement de la mémoire autobiographique dans un contexte de traumatisme psychique

    No full text
    Psychological trauma defines the emotional shock experienced by an individual following a traumatic event. In some cases, the psychotraumatic symptomatology develops and persists, leading to the onset of posttraumatic stress disorder. The literature has widely described the memory impairment associated with the disease, especially dysfunction of autobiographical memory. This complex memory system contains the story of our past, on which our present identity and future aspirations are based. However, it remains unclear whether this deficit is due to premorbid autobiographical memory dysfunction, to the trauma exposure itself, or to the subsequent development of posttraumatic stress disorder symptomatology. Research has not yet clarified the relationship between autobiographical memory dysfunction and psychological trauma. Throughout this work, we will define autobiographical memory function in the context of psychological trauma. The first two studies will analyze autobiographical memory function following a single traumatic exposure and following repeated exposures. The final study will shed light on how autobiographical memory functions among participants with posttraumatic stress disorder in partial remission.Le traumatisme psychique dĂ©finit le choc Ă©motionnel d'un individu Ă  la suite Ă  d'un Ă©vĂšnement traumatique. Dans certains cas, la symptomatologie psychotraumatique s'installe et perdure entrainant l'apparition d'un Trouble de Stress Post Traumatique. La littĂ©rature dĂ©crit amplement les dĂ©sordres mnĂ©siques qui accompagnent la maladie et notamment l'altĂ©ration de la mĂ©moire autobiographique. Ce systĂšme de mĂ©moire complexe renferme l'histoire de notre passĂ© sur laquelle s'appuie notre individualitĂ© prĂ©sente et nos aspirations futures. Cependant, l'origine du dysfonctionnement de la mĂ©moire autobiographique reste confuse, cette altĂ©ration pourrait ĂȘtre un facteur prĂ©morbide, la consĂ©quence de l'exposition traumatique ou celle de la maladie. Les recherches restent incertaines sur les relations existantes entre le dysfonctionnement de la mĂ©moire autobiographique et le traumatisme psychique. Tout au long de ce travail, nous caractĂ©riserons le fonctionnement de la mĂ©moire autobiographique dans le contexte d'un traumatisme psychique. Les deux premiĂšres Ă©tudes permettront d'analyser la mĂ©moire autobiographique suite Ă  une exposition traumatique unique et suite Ă  des expositions rĂ©pĂ©tĂ©es. La derniĂšre Ă©tude nous Ă©clairera sur le fonctionnement de la mĂ©moire autobiographique chez des sujets en rĂ©mission partielle d'un trouble de stress post traumatique

    Recherches sur le potentiel aromatique des raisins de Vitis vinifera L. cv. Sauvignon blanc

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    Le développement d'une méthode de dosage par dilution d'isotopes stables, de trois S-conjugués à la cystéine, précurseurs de thiols volatils responsables de l'arÎme du Sauvignon, permet d'apprécier le potentiel aromatique des raisins de ce cépage. Cette méthode est un dosage indirect des précurseurs cystéinylés, basée sur l'analyse des thiols volatils correspondants, libérés par percolation du moût sur une colonne de tryptophanase immobilisée. Au cours de la maturation, l'évolution des teneurs en précurseurs cystéinylés du raisin varie en fonction du S-conjugué à la cystéine considéré et des conditions climatiques du millésime L'alimentation en eau joue un rÎle essentiel sur le potentiel aromatique des raisins. La distribution des précurseurs cystéinylés dans la baie diffÚre selon le précurseur considéré : 80 % des S-4-(4-méthylpentan-2-one)-L-cystéine et S-4-(4-méthylpentan-2-ol)-L-cystéine se situent dans le jus et plus de 50 % du S-3-(hexan-1-ol)-L-cystéine (P-3MH) sont dans la pellicule. Par conséquent, la macération pelliculaire améliore le potentiel aromatique du moût mais a une incidence essentiellement sur le P-3MH. Les thiols volatils sont libérés à partir de leur précurseur sous l'action de la levure. La révélation du potentiel aromatique du sauvignon dépend donc entiÚrement de la fermentation alcoolique. Le taux de transformation des précurseurs cystéinylés en arÎme est trÚs faible. De plus, le taux de dégradation des S-conjugués à la cystéine varie en fonction de la souche de levure inoculée, mais il est davantage influencé par la composition du moût. L'identification du S-3-(hexan-1-ol) glutathion dans le moût de sauvignon fournit des indications sur la voie de biosynthÚse du P-3MH dans la vigne, car les S-conjugués au glutathion sont généralement impliqués dans les voies de détoxification chez les organismes vivants.BORDEAUX2-BU Santé (330632101) / SudocBORDEAUX1-BU Sciences-Talence (335222101) / SudocVILLENAVE D'ORNON-Bib. ISVV (335502201) / SudocSudocFranceF
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