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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Fehler, Konflikte und Dopamin. Funktionelle Grundlagen zur Error-Related Negativiy (ERN/Ne) / Errors, conflicts and dopamine. Funktional basics of the Error-Related Negativity (ERN, Ne)

Ganasinski, Eva January 2015 (has links) (PDF)
Anhand eines modifizierten Eriksen Flanker Task untersuchten wir die Ausprägung der ERPs (ERN, Fb-ERN und Pe) in Abhängigkeit der Fehlerart, Stimulusinterferenz und Fehlererwartung. Desweitern wurde die Auswirkung der Katechol-O-Methyltransferase (COMT) und ihre Auswirkung auf die ERPs untersucht. Außerdem erfolgte eine explorative Untersuchung des Einflusses emotionaler Aspekte auf die ERPs. Unsere Ergebnisse sollten mit den zentralen Fehlerverarbeitungstheorien die auf diesem Gebiet existieren verglichen werden. Anhand unserer Ergebnisse konnten viele Übereinstimmungen zur Theorie des Verstärkungslernens aufgezeigt werden, wonach Dopamin bei ehlerverarbeitungsprozessen und Modulation der ERN eine entscheidende Rolle spielt. Wir fanden eine deutliche Modulation der ERN in Abhängigkeit der COMT-Genotypen. Außerdem konnten wir nachweisen, dass motivationale und affektive Faktoren die ERN beeinflussen. / We investigated the alteration of the ERPs (ERN, Fb-ERN and Pe) dependent to the type of an error, stimulus-interference and prediction of an error. Furthermore we investigated the modulation of the ERPs according to the genotype of the Katechol-O-Methytransferase. Moreover we examined the influence of emotions to the ERPs. Our results were compared to the central theories of error procession. Many our results were to be explained by the reinforcement learning theorie, whereto dopamine plays an important role within error procession and modulation of the ERN. We found a modulation of the ERN in accordance to the COMT-Genotype. Moreover we detected an alteration of the ERN in dependence to motivational and affective factors.
2

Einfluss des Trinkverhaltens auf „Cue-Reaktivität“ und neurophysiologische Korrelate der Handlungsüberwachung in einem modifizierten Eriksen Flanker Task / Effects of drinking behavior on "Cue-reactivity" and neurophysiological correlates of action monitoring in a modified Eriksen Flanker Task

Nutzhorn, Maren January 2012 (has links) (PDF)
EEG-Studie zur Testung der ERN bei Viel- und Wenigtrinkern mittels eines modifizierten Eriksen Flanker Task. Zusätzlich wurde der Einfluss von Alkoholbildern auf die Handlungsüberwachung getestet, um eine "Alkohol-Cue-Reaktivität" zu untersuchen. / EEG study that tests the error-related negativity of heavy and light social drinkers using a modified version of the Eriksen Flanker Task. Additionally the impact of alcoholic images was tested on the action-monitoring to examine the "alcohol-cue reactivity".
3

The Psychophysiology of Intrusive Cognitions: Comparing Thought Suppression Vs Acceptance

Santerre, Craig Lee January 2007 (has links)
Intrusive cognitions are a natural occurrence within our stream of consciousness, however, when they become repetitive, negative, distressing, and difficult to control, they may warrant clinical concern. Thought suppression is a common control strategy used to manage intrusive thoughts even though research suggests it may actually exacerbate the problem. Conversely, acceptance-based interventions have gained recent attention as an alternative strategy for managing distressing internal experiences. Only preliminary research has focused on the psycho- and neurophysiological bases of intrusive cognitions, and their relationship to cognitive control strategies. Evidence suggests that the anterior cingulate cortex (ACC) may be a brain region critically involved in this process. The present investigation compared the subjective, behavioral, and physiological effects of a thought suppression and acceptance strategy in a sample of university students with high or low obsessive-compulsive (OC) characteristics who were exposed to an emotion-evoking film clip. Participants were instructed either to suppress or accept any intrusive cognitions during a rest period after the film clip, while monitoring for the number of intrusions. Next, psychophysiological signals and reaction times were measured while participants performed a variant of the Stroop task. The commission of errors during a forced choice task generates an error-related negativity (ERN), which is believed to index activity in the ACC. Results showed that self-reported intrusions during the rest interval were greater for the acceptance group and the high-OC group. Correlations suggested that participants who reported more effort at suppression also indicated more distress about their thoughts, whereas those who reported more acceptance indicated less distress. During Stroop task errors, the ERN was apparent as a maximal frontal negativity, and was larger for the suppression group than the acceptance group at a frontal scalp site (Fz), but not a central scalp site (Cz). Correlations between self-reported intrusions at rest and ERN amplitude indicated that participants who reported fewer intrusions demonstrated enhanced ERNs, a marker for increased ACC activity. These findings may be interpreted as supporting the hypothesis that thought suppression is associated with increased ACC activity and greater self-reported discomfort with the intrusions.
4

Rozanov and the word

Dimbleby, Liza Lucasta January 1996 (has links)
The thesis is an attempt to relate aspects of Rozanov's writing to the Russian tradition of the word, as exemplified in the work of writers and thinkers, contemporary and near-contemporary to Rozanov. The first part establishes key features of this tradition through the work of writers such as Ern, Losev, Mandel'shtam and Averintsev. The relevance of Bakhtin for a reading of Rozanov, and of Rozanov for reading Bakhtin, is argued through an extended comparison of the two writers in the context of the Russian tradition of the word. Aspects of Rozanov's thought and formal expression, such as silence, intonation and the resisting of definition are discussed in relation to this tradition. The role of intimate genres and the reader is discussed with reference to Dostoevskii, Rozanov and Bakhtin. Rozanov's use of letters, footnotes and the idea of manuscripts is examined as a part of his battle with received literary forms. The second part looks at these various aspects of Rozanov's work in relation to his contemporary context; to the writing of the obscure 'literary exiles' and that of Solov'ev and Merezhkovskii. Rozanov's particular sense of the word is argued to be crucial in his attitude towards these writers. Rozanov's involvement with the decadents is discussed, and his exemplification of themes of sectarianism and apocalypse in his writing. The thesis ends with a look at the paradoxes of Rozanov's own role as a writer supposedly in battle with literature, and the relation between his need for words and his need for belief.
5

The Interaction of State and Trait Worry on Response Monitoring in Those with Worry and Obsessive-Compulsive Symptoms

Zambrano-Vazquez, Laura, Zambrano-Vazquez, Laura January 2016 (has links)
The error related negativity (ERN) is an event-related brain potential that is sensitive to errors. It reflects individual differences in the extent to which individuals recruit neural systems involved in monitoring errors and systems for cognitive control that then make adjustments to future behavior. It has been closely linked to anxiety through diverse disorders and symptoms, but recently evidence highlights the role of anxious apprehension as a key individual difference related to error monitoring. Diverse hypotheses have emerged to explain this relationship. While some views emphasize the role of motivation and emotion, others suggest that a transient compensatory control is responsible for this relationship. Although both theories recognize the potential for state anxiety to potentiate the ERN, there is limited literature that allows a comparison of these competing hypotheses. The present study investigated the interaction of state and trait anxiety on the ERN by comparing ERN amplitude before and after a five minute worry induction period that specifically targeted each individual's greatest current worries. Results did not unequivocally support one specific theory, but rather provide some preliminary evidence of how trait and state worry may interact and affect the ERN. Suggestions for future research are provided, including using worry induction paradigms in which the worries increase threat or significance of errors.
6

Towards an Examination of Error Related Neural Processes in Real-World Tasks: ERP Evidence of Uncertainty, Expectancy, Difficulty and Anxiety

Stewart, Peter C. 08 1900 (has links)
<p> In four experiments I addressed factors that affect human performance monitoring as indicated by neural correlates observed in response-locked event related potentials. Specifically, I examined modulations of the error related negativity (ERN), the correct response negativity (CRN), and the error positivity (Pe) components across a variety of conditions. These components, all thought to be generated in the anterior cingulate cortex, represent activation of the performance monitoring system. Experiments 1 and 2 used stimulus congruency and visual noise to manipulate response and stimulus uncertainty in an extension of previous research. These manipulations, together with a between experiment task manipulation, examined the role of cognitive/attentional load in performance monitoring. Replication of previous findings and a task specific modulation of ERN amplitudes provided support for a role of cognitive load in performance monitoring. Further, these two experiments used a novel task and novel stimuli to replicate previous research and extend our knowledge of how uncertainty affects performance monitoring. In stark comparison to all previous research in this area, Experiments 3 and 4 both employed complex and somewhat ecologically valid tasks. Standard ERN/Pe results in Experiment 3 (touch typing task) revealed that it is possible to examine the ERN in more complex, real world-like tasks. Further, an expectancy manipulation elicited marginal differences in the response-locked Pe but resulted in large N1 and P3 differences suggesting a possible role of attention in early expectation driven performance monitoring adjustments. Experiment 4 examined the role of task difficulty, anxiety level and exposure (i.e., time on task) for effects on ERN and Pe amplitudes. By comparing how math anxious people perform in a math environment, this study represents the first to pit a specific anxiety against a specific anxiety provoking situation. This complex paradigm again replicated general ERN findings providing further support for the validity of complex task usage. Findings surrounding the difficulty manipulation and anxiety measures provide new insight into the role of difficulty in performance monitoring and support the importance of considering personality characteristics in self-regulation. </p> / Thesis / Doctor of Philosophy (PhD)
7

Die Bedeutung des Thalamus für das menschliche Handlungsüberwachungssystem im fronto-striato-thalamo-corticalen Netzwerk

Seifert, Sebastian 26 November 2012 (has links) (PDF)
Für das zielgerichtete Verhalten des Menschen ist ein funktionierendes Handlungsüberwachungssystem eine wichtige Voraussetzung. Somit können Fehlhandlungen registriert und verarbeitet werden, um dann anschließend das Verhalten an die entsprechende Situation besser anzupassen. Ein wichtiges neuroanatomisches Korrelat dieses Handlungsüberwachungssystems ist der anteriore Anteil des mittleren cingulären Cortex (anterior midcingulate cortex, aMCC), der in der Funktion der Fehlerverarbeitung eng mit den Basalganglien und dem lateralen präfrontalen Cortex verknüpft ist. In der vorliegenden Arbeit wurde die Bedeutung des Thalamus im Netzwerk der Fehlerverarbeitung genauer untersucht. Es konnte mittels diffusionsgewichteter Traktografie bei 16 gesunden Probanden gezeigt werden, dass speziell der Nucleus ventralis anterior (VA) und der Nucleus ventralis lateralis anterior (VLa) quantitativ stärkere Faserverbindungen mit dem aMCC aufweisen, als die restlichen Thalamuskerne. Desweiteren zeigten 15 Patienten mit Läsionen im Thalamus im Vergleich zur gesunden Kontrollgruppe im Eriksen Flanker Task fehlerspezifische Verhaltensunterschiede. Obwohl die Fehlerrate zwischen diesen Patienten und den Kontrollprobanden nahezu identisch war, konnten die Patienten ihre Fehler als solche signifikant schlechter detektieren und ihr Verhalten nach einem Fehler daher auch schlechter anpassen. Die EEG Daten zeigten für die Patientengruppe eine in der Amplitude signifikant verminderte error-related negativity (ERN – ein ereignis-korreliertes Hirnpotential, ausgelöst durch Fehlhandlungen, z.B. in Flankierreizaufgaben) im Vergleich zur Kontrollgruppe. Bei 6 Patienten mit Läsionen der VA und VLa Kerngruppe war die ERN nahezu komplett erloschen, wohingegen bei den 9 Patienten, deren Läsionen nicht VA und VLa betrafen, die ERN lediglich vermindert war. / Performance monitoring is an essential prerequisite of successful goal-directed behavior. Research of the last two decades implicates the anterior midcingulate cortex (aMCC) in the human medial frontal cortex and frontostriatal basal ganglia circuits in this function. Here, we addressed the function of the thalamus in detecting errors and adjusting behavior accordingly. Using diffusion-based tractography we found that, among the thalamic nuclei, the ventral anterior and ventral lateral anterior nuclei (VA, VLa) have the relatively strongest connectivity with the RCZ. Patients with focal thalamic lesions showed diminished error-related negativity, behavioral error detection, and post-error adjustments. When the lesions specifically affected the thalamic VA/VLa nuclei these effects were significantly pronounced, which was reflected by complete absence of the error-related negativity. These results reveal that the thalamus, particularly its VA/VLa region, is a necessary constituent of the performance-monitoring network, anatomically well connected and functionally closely interacting with the aMCC.
8

Modélisation chimique détaillée de la combustion de la biomasse dans les appareils de chauffage domestique en vue de réduire leurs émissions polluantes / Detailed chemical modeling of biomass combustion in domestic heating appliances in order to reduce their polluting emissions

Dhahak, Amal 28 March 2019 (has links)
Cette thèse vise à comprendre et à modéliser les mécanismes chimiques de combustion de la biomasse dans les appareils de chauffage domestiques afin de réduire les émissions polluantes. Dans ce but, un modèle global de combustion a été développé. Ce modèle considère à la fois une cinétique chimique détaillée et le transfert thermique. La première partie de ce travail a consisté à développer un modèle cinétique permettant de représenter la dévolatilisation de la biomasse ainsi que les réactions secondaires de combustion en phase gazeuse des espèces émises au cours de la pyrolyse primaire. Selon le modèle cinétique de pyrolyse utilisé, la biomasse est caractérisée comme étant un mélange de trois constituants dits de référence : la cellulose, l’hémicellulose et la lignine. Pour connaître les limitations du modèle étudié, il a été testé sur plusieurs cas de pyrolyse primaire. Un modèle de pyrolyse secondaire et de combustion a été ajouté au modèle représentant la pyrolyse primaire. Ce modèle secondaire est composé de mécanismes d'oxydation pour les produits formés par la pyrolyse, comme l’hydroxyacétaldéhyde, le furane et ses dérivés, l’anisole, le furfural, le gaïacol… Ce modèle secondaire, ainsi que le nouveau modèle global développé, BioPOx (Biomass Pyrolysis and Oxidation), ont été testés sur un grand nombre de points expérimentaux. Dans une seconde partie, le modèle cinétique considérant à la fois la pyrolyse primaire et le craquage thermique des espèces gazeuses émises, est couplé à un modèle de transfert de chaleur simplifié afin de modéliser la combustion d’une bûche de bois dans un poêle représenté par un réseau de réacteurs chimiques idéaux. Le modèle global, couplant les parties cinétique et thermique, permet de reproduire des résultats expérimentaux sur des émissions gazeuses (CO, CO2, NO) obtenues dans un poêle à bois. / This thesis aims to understand and model the chemical mechanisms of biomass combustion in domestic heating appliances to reduce polluting emissions. For this purpose, a global model of combustion has been developed. This model considers both detailed chemical kinetics and heat transfer. The first part of this work consisted of developing a kinetic model to represent the devolatilization of biomass as well as the secondary gas phase combustion reactions of the species emitted during primary pyrolysis. According to the used kinetic model of pyrolysis, the biomass is characterized as a mixture of three so-called reference constituents: cellulose, hemicellulose and lignin. To know the limitations of the studied model, it has been tested on several cases of primary pyrolysis. A model of secondary pyrolysis and combustion was added to the model representing primary pyrolysis. This secondary model is composed of oxidation mechanisms for products formed by pyrolysis, such as hydroxyacetaldehyde, furan and its derivatives, furfural, anisole, guaiacol ... This secondary model, as well as the new global model developed BioPOx (Biomass Pyrolysis and Oxidation) have been tested on a large number of experimental results. In a second part, the kinetic model considering both the primary pyrolysis and the thermal cracking of the emitted gaseous species, is coupled to a simplified model of heat transfer to model the combustion of a log of wood in a stove represented by a network of ideal chemical reactors. The global model, coupling the kinetic and thermal parts, reproduces experimental results on gaseous emissions (CO, CO2, NO) obtained in a wood stove.
9

Régulation et fonctions de facteurs de transcription ERF ERN au cours de la symbiose entre Medicago truncatula et Sinorhizobium meliloti. / Regulation and functions of ERF ERN transcription factors during root nodule symbiosis between Medicago truncatula and Sinorhizobium meliloti

Cerri, Marion 20 February 2013 (has links)
Les légumineuses sont capables de s’associer en symbiose avec des bactéries du sol Rhizobium. Cette interaction culmine par la formation d’un nouvel organe racinaire appelé nodule, à l’intérieur duquel les bactéries différentiées fixent l’azote atmosphérique sous une forme assimilable par la plante hôte. La mise en place de cette association repose sur un dialogue moléculaire entre les deux partenaires, faisant intervenir des signaux bactériens lipo-chitooligosaccharidiques appelés Facteurs Nod (FNods). Chez la légumineuse modèle Medicago truncatula, la perception de ces signaux symbiotiques au niveau de l’épiderme racinaire, initie une voie de signalisation qui conduit à des oscillations calciques nécessaires pour l`activation de gènes de la plante hôte, tel le gène marqueur ENOD11. Il a été montré que les facteurs de transcription ERF ERN1/ERN2, étroitement apparentés, agissent comme des activateurs directs de la transcription d’ENOD11, via leur liaison à la séquence cis régulatrice NFbox. Le mutant ern1 est de manière cohérente requis pour l’activation d’ENOD11 en réponse aux FNods mais également au cours des étapes suivantes d’infection et de développement nodulaire. Cependant, ce mutant présente un phénotype symbiotique partiel soulevant la question d’une redondance fonctionnelle, qui pourrait être attribuée à la présence du facteur ERN2, étroitement apparenté. Ainsi, au cours de ma thèse, j’ai étudié la relation fonctionnelle entre les facteurs ERN1/ERN2 par de approches diverses visant à déterminer leur expression et fonctions relatives au cours de la symbiose rhizobienne. Mon travail de thèse a dans tout d’abord porté sur l’étude des profils d’expression spatio-temporels de gènes ERN au cours de la symbiose rhizobienne, corroborée par la dynamique de localisation cellulaire des protéines de fusions ERN. Ces facteurs sont exprimés de manière séquentielle mais aussi conjointe aux cours de la signalisation FNods et l’infection rhizobienne. Par la suite, des expériences de complémentation croisée, dans le fond mutant ern1, ont montré qu’ERN2 peut remplacer ERN1 pour l’induction d’ENOD11 en réponse aux FNods et pour la formation de nodules, dès lors qu’il est exprimé sous le contrôle du promoteur d’ERN1. Ceci indique que ces facteurs ont des activités biologiques similaires et suggère que l’absence de complémentation d’ern1 par le facteur endogène ERN2 est probablement liée à une régulation transcriptionnelle différentielle de la part de leurs promoteurs. Enfin, nous avons initié la caractérisation phénotypique de nouvelles lignées mutées au niveau du gène ERN2, dans le but d’identifier les fonctions spécifiques de ce facteur au cours de la nodulation. A travers l’analyse d’une lignée Tilling (ern2.1) présentant une mutation ponctuelle dans le domaine de liaison à l’ADN, nous avons mis en évidence un rôle d’ERN2 dans la progression des cordons d’infection au niveau du cortex racinaire. Des études moléculaires ont permis de montrer que l’acide aminé muté est un résidu conservé et important pour la topologie du domaine de liaison à l’ADN, mais également pour l’activité transcriptionnelle d’ERN2 sur ENOD11. Contrairement à ern1, le mutants ern2.1 et ern2.2 (mutant d’insertion) sont capables de former des nodules. Néanmoins, l’infection nodulaire apparait dans les deux cas parfois défectueuse, conduisant à une sénescence précoce. Ces résultats démontrent qu’ERN2 remplit aussi des rôles spécifiques au cours de la nodulation, qui ne sont pas entièrement complémentés par ERN1. Il semblerait donc que les facteurs ERN contrôlent des étapes communes et divergentes de l‘infection rhizobienne, ERN1 ayant un rôle prépondérant dans l`initiation et progression de l’infection tandis qu’ERN2 aurait un rôle secondaire, plus centré dans la progression des cordons. La lignée double mutant ern1ern2.1, ouvre de nouvelles perspectives pour l’étude de la redondance fonctionnelle entre ces deux facteurs au cours des symbioses racinaires / Legumes are able to associate in symbiosis with Rhizobia bacteria in the soil, which culminates in the formation of a new organ referred to as the root nodule, within which differentiated bacteria fix nitrogen to the benefit of the host plant. The establishment of this association relies on a molecular dialogue between the two partners, involving bacterial lipo-chitooligosaccharide signals called Nod factors (NF). In the model legume Medicago truncatula, the perception of these symbiotic signals in the root epidermis, initiates a signaling pathway that leads to calcium oscillation responses required for the activation of downstream genes such as the well-characterized ENOD11. Previously, ERN1 and the closely-related ERN2 transcription factors (TFs) were reported as direct activators of ENOD11 via binding to the NFbox regulatory unit. In addition, phenotypic analysis of the ern1 knockout mutant has confirmed the importance of ERN1 not only during NF signaling but also throughout subsequent infection and nodule development stages. Nevertheless, the ern1 mutant displays a less severe phenotype compared to plants mutated in other NF signaling genes, raising the question of a possible functional redundancy with the endogenous closely-related ERN2 factor. My PhD project was focused on the study of the functional relationship between ERN1 and ERN2 TFs. By using a variety of strategies we aimed at determining both ERN expression profiles and relative functions during nodulation. We first examined the spatio-temporal expression profiles of these genes during rhizobial symbiosis and correlated this with the dynamics of cellular localization of ERN fusion proteins. These analyses revealed that these factors possess both common and distinct expression profiles, correlated with cell-type specific and dynamic in vivo protein accumulation, tightly associated with rhizobial pre-infection and subsequent infection stages in M. truncatula. Further cross-complementation studies in the ern1 mutant background showed that, when ERN2 is expressed under the control of the ERN1 promoter, it can fully restore the ern1 phenotype regarding NF-elicited ENOD11 activation and nodule formation. This indicates that these factors have similar biological activities and suggests that the incapacity of endogenous ERN2 to complement the ern1 mutant is mainly due to differences in their promoter activities. Finally, we also initiated a phenotypic characterization of M. truncatula ern2 mutant lines, in order to get a better insight into ERN2 specific functions during nodulation. The phenotypic analysis of a Tilling line (ern2.1) carrying a point mutation in a conserved amino acid in the ERN2 DNA binding domain, revealed a role for ERN2 during infection thread progression in the root cortex. Further molecular studies demonstrated that this mutated amino acid in the Tilling line is conserved and required for optimal DNA binding domain topology and transcriptional activity of ERN2 on its target ENOD11 gene. In addition, the ern2.1 line and a second ern2.2 insertional mutant line are both capable of forming nodules, in contrast to the ern1 mutant. Nevertheless, these nodules are partly infection defective leading to premature senescence. These findings provide evidence that ERN2 possesses specialized functions during nodulation that cannot be fully complemented by ERN1. This suggests that ERN possess common and divergent functions, ERN1 having a predominant role in rhizobial infection initiation and progression while ERN2 having a secondary and more centered role during infection thread progression. The ern1ern2.1 double mutant line, recently generated during my PhD, opens new perspectives to further study the functional relationship between ERN TFs during root endosymbioses.
10

Composição fenólica e atividade biológica in vitro e in vivo de frutas nativas brasileiras / Phenolic composition and biological activity in vitro and in vivo of Brazilian native fruits

Soares, Jackeline Cintra 03 April 2018 (has links)
O Brasil possui condições climáticas adequadas para o desenvolvimento de um grande número de frutas nativas e essa biodiversidade tem se tornado um caminho promissor para a descoberta de novos compostos bioativos capazes de ser utilizados na formulação de alimentos funcionais e medicamentos. Os compostos fenólicos apresentam ações específicas, podendo atuar como antioxidantes e anti-inflamatórios, assim prevenindo doenças crônicas. Diante do exposto, o objetivo deste trabalho foi avaliar o potencial antioxidante, antiinflamatório e a composição fenólica de dez frutas nativas brasileiras ainda pouco conhecidas: araçá-boi (Eugenia stipitata), cambuití-cipó (Sagerectia elegans), murici vermelho (Bysonima arthropoda), murici guassú (Byrsonima lancifolia), morango silvestre (Rubus rosaefolius), cambuci (Campomanesia phaea), jaracatiá-mamão (Jacaratia spinosa), juquirioba (Solanum alterno-pinatum), fruta-do-sabiá (Acnistus arborescens) e cajá (Spondias mombin L.). Os extratos etanólicos (80% v/v) das polpas foram analisados inicialmente quanto à capacidade de sequestro dos radicais ABTS&#8729+ e ROO&#8729. A atividade anti-inflamatória foi avaliada in vivo por meio do modelo de migração de neutrófilos induzida por carragenina, enquanto que a composição fenólica foi realizada por técnicas cromatográficas (CLAE-DAD e CG-EM). As 5 frutas com as maiores atividades biológicas foram ainda analisadas quanto à capacidade de sequestro de O2 &#8729-, HOCl e NO&#8729, atividade anti-inflamatória por meio do ensaio de ativação do fator nuclear-&kappa;B (NF-&kappa;B) e composição fenólica por espectrometria de massas de alta resolução (LC-ESI-QTOF-MS). Em relação ao sequestro do radical ABTS&#8729+ o cambuití-cipó apresentou a maior atividade (749,88 &mu;mol TE.g-1) e para o ROO&#8729 o murici vermelho apresentou a maior atividade antioxidante (559,09 &mu;mol TE.g-1). Os animais tratados com araçá-boi, cambuití-cipó, murici vermelho, cajá e morango silvestre apresentaram reduções no influxo de neutrófilos comparados ao grupo carragenina (p < 0,05). Por meio das técnicas de CLAE-DAD e CG-EM foi possível identificar compostos fenólicos pertencentes a classe dos flavonoides (catequina, epicatequina, rutina, quercetina glicosilada, kaempeferol glicosilado, quercetina, procianidina B1 e procianidina B2), sub-classe do ácido hidroxibenzóico (ácido gálico) e sub-classe dos ácidos hidrocinâmicos (ácido cumárico, ácido ferúlico e caféico). O araçá-boi, cambuití-cipó, murici vermelho, morango silvestre e cajá foram as cinco frutas que apresentaram as maiores atividades antioxidantes e/ou anti-inflamatórias, cujo perfil fenólico por LC-ESI-QTOF-MS indicou a presença de 18 compostos no araçá-boi, 32 no cambuitícipó, 26 no murici vermelho e 20 e 11 compostos no morango silvestre e cajá, respectivamente. Vários dos compostos fenólicos identificados foram encontrados pela primeira vez nessas espécies. O cambuiti-cipó e murici vermelho se destacaram em relação ao sequestro de HOCl (EC50 4,99 e 4,41 &mu;g mL-1, respectivamente) e o cambuití-cipó foi o mais ativo para desativar o radical O2 &#8729- (EC50 68,33 &mu;g mL-1) e NO&#8729 (EC50 0,78 &mu;g mL-1). Já os extratos de murici-vermelho, cambuití-cipó e morango silvestre inibiram significativamente a ativação do NF-&kappa;B. Portanto, as frutas nativas brasileiras são fontes de substâncias antioxidantes e anti-inflamatórias, bem como de uma grande diversidade de compostos fenólicos, os quais podem propiciar importantes benefícios para a saúde humana. / Brazil has favorable climatic conditions for the development of a large number of native fruits and this biodiversity has become a promising path towards the discovery of new bioactive compounds capable of being used in the formulation of functional foods and medicines. Phenolic compounds show specific action mechanisms, being able to act as antioxidants and anti-inflammatories, thus preventing chronic diseases. However, few Brazilian native fruits are well known and consumed by the population, undermining the investigation of chemical composition as well as the identification/quantification of bioactive compounds. In light of this, the objective of this work was to evaluate the antioxidant and anti-inflammatory potentials as well as the phenolic composition of ten underexploited Brazilian native fruits, namely: araçá-boi (Eugenia stipitata), cambuití-cipó (Sagerectia elegans), murici vermelho (Bysonima arthropoda), murici guassu (Byrsonima lancifolia), morango silvestre (Rubus rosaefolius), cambuci (Campomanesia phaea), jaracatiá-mamão (Jacaratia spinosa), juquirioba (Solanum alterno-pinatum), fruto-do-sabiá (Acnistus arborescens) and cajá (Spondias mombin L.). Pulps ethanolic extracts (80%, v/v) were initially analyzed regarding scavenging capacity of the ABTS&#8729+ and ROO&#8729 radicals. Antiinflammatory activity was evaluated in vivo using the carrageenan-induced neutrophil migration model, while phenolic composition was determined by chromatographic techniques (HPLC-PAD and GC-MS). The five fruits with the highest biological activities were analyzed for O2&#8729-, HOCl and NO&#8729 radicals scavenging capacities, for in vitro anti-inflammatory activity by nuclear factor-&kappa;B (NF-&kappa;B) activation, and for phenolic composition by High Resolution Mass Spectrometry (LC-ESI-QTOF-MS). In relation to ABTS&#8729+ radical scavenging cambuiticipó showed the highest activity (749.88 &mu;mol TE.g-1), while for ROO&#8729 scavenging, murici vermelho had the highest antioxidant activity (559.09 &mu;mol TE.g-1). The animals treated with araçá-boi, cambuití-cipó, murici vermelho, cajá and morango silvestre reported decreases in neutrophils influx compared to carrageenan group (p <0.05). It was possible to identify by HPLC-DAD and GC-MS techniques phenolic compounds belonging to the class of flavonoids (catechin, epicatechin, rutin, glycosylated quercetin, glycosylated kaempeferol, quercetin, procyanidin B1 and procyanidin B2), subclass of hydroxybenzoic acid (gallic acid) and subclass of hydrocinnamic acids (coumaric, ferulic and caffeic acids). Araçá-boi, cambuitícipó, murici vermelho, morango silvestre and cajá were the five fruits with the highest antioxidant and / or anti-inflammatory activities. The phenolic profile analysis by LC-ESIQTOF- MS pointed the presence of 18 compounds in araçá-boi, 32 in cambuití-cipó, 26 in murici vermelho, 20 in morango silvestre and 11 in cajá. Several of the identified phenolic compounds were found for the first time in these fruit species. Cambuiti-cipó and murici vermelho stood out in relation to HOCl scavenging (EC50 4.99 and 4.41 &mu;g.mL-1, respectively) and cambuití-cipó was the most active to deactivate both O2 &#8729- radical (EC50 68.33 &mu;g.mL-1) as NO&#8729 (EC 500.78 &mu;g.mL-1). Murici vermelho, cambuití-cipó and morango silvestre extracts significantly inhibited the activation of NF- &kappa;B.Therefore, Brazilian native fruits are sources of antioxidant and anti-inflammatory substances, as well as a great diversity of phenolic compounds, which can provide important benefits for human health.

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