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Made available in DSpace on 2014-12-17T15:37:23Z (GMT). No. of bitstreams: 1 VivianeSM.pdf: 285646 bytes, checksum: 806d8cb57146ca69bbc7d647f187939d (MD5) Previous issue date: 2007-05-07 / The stress responses can be parameters used in order to identify the welfare of animals. Behavior parameters can also be regarded as means to identify their relation to stressing situations. In this study, adult male and female poodle dogs, accustomed (group 1) or not (group 2) to the environment of a bath and grooming salon were analyzed through the plasmatic concentration of cortisol, cell counting of the immune system (total leukocytes and percentage of neutrophils and lymphocytes) and through observation of changes in behavior before and after the bath and grooming service. After arriving at the kennel, the dogs were taken to the bath and grooming facility, where they had their blood samples taken and were observed for ten minutes. The subsequent procedures consisted of the bath and grooming services and the collection of another blood samples. The research results were analyzed through non-parametric statistic tests and p < 0.05. Accustomed and non-accustomed dogs presented different hormonal and behavior responses: accustomed dogs presented an increasing of the cortisol level at the second blood samples collection, thus indicating stress towards the aforementioned procedures and presenting behavior responses which can be described as moderated stress. Non-accustomed dogs presented the same cortisol levels in both first and second samples suggesting that they were already reacting to the new environment. Dogs also shown behavioral responses which can be described as acute stress. Both male and female dogs showed similar immunological changes as well as different endocrine and behavioral profiles. Concerning aggression, this study demonstrates that biting the owner can be a predicting behavior of aggression during the bath and grooming service, male dogs were more aggressive than the female, and that males were more reactive to unknown caretaker. The results of this research propose that the familiarization of the animal with the bath and grooming environment and caretaker is important to the welfare of poodle dogs, especially to that of male dogs / As respostas de estresse podem ser vari?veis utilizadas para identificar o n?vel de bem-estar dos animais. Par?metros comportamentais tamb?m podem ser usados tentando identificar sua correspond?ncia com situa??es estressantes. Neste estudo c?es da ra?a poodle, adultos, de ambos os sexos, familiarizados (Grupo 1) e n?o familiarizados (Grupo 2) a um ambiente de sal?o de beleza canino foram avaliados por meio da concentra??o plasm?tica de cortisol, contagem de c?lulas do sistema imune (leuc?citos totais e percentuais de neutr?filos e linf?citos) e observa??o de altera??es comportamentais antes e ap?s os procedimentos de banho e tosa. Ap?s a chegada do animal no canil, dentro do ambiente de banho e tosa, foi realizada uma primeira coleta de sangue seguida por um intervalo de observa??o de 10 minutos, realiza??o dos procedimentos de banho e tosa e coleta de uma segunda amostra de sangue. Os resultados foram analisados usando testes estat?sticos n?o param?tricos e o valor de p < 0.05. C?es familiarizados e n?o familiarizados tiveram respostas hormonais e comportamentais diferentes: os c?es familiarizados apresentaram eleva??o do cortisol na segunda coleta, indicando o estresse provavelmente aos procedimentos, e respostas comportamentais que podem ser caracterizadas como estresse moderado. Os c?es n?o familiarizados ao ambiente apresentaram concentra??es semelhantes de cortisol na primeira e segunda coletas sugerindo que a situa??o estressante parece ser anterior aos procedimentos, provavelmente relacionada ao novo ambiente. Apresentaram tamb?m respostas comportamentais que podem ser caracterizadas como estresse agudo. Machos e f?meas apresentaram altera??es imunol?gicas semelhantes e altera??es end?crinas e comportamentais diferentes entre os sexos nos dois grupos experimentais. Com rela??o ? agressividade observou-se que morder o propriet?rio ? um bom preditor de agressividade durante os procedimentos de banho e tosa, os machos foram mais agressivos que as f?meas e reagiram mais a um tosador estranho. Estes resultados sugerem que a familiaridade do animal ao ambiente de tosa e banho e ao tosador ? importante para o bem-estar animal de c?es da ra?a poodle, particularmente nos machos

This dissertation identifies factors causing the burnout syndrome, which occur especially in the area of work career. It discusses risks that cause the burnout syndrome and the possibilities of its prevention. The theoretical part analyses particular aspects of burnout and describes career as a significant part of human life. The second part of the dissertation evaluates research that was conducted in a chosen organisation. Findings regarding a stress prevention programme are discussed in the second part, as well as the topic of how ready participants are to use the gained knowledge in real life. The paper also assesses how employees and their supervisors evaluate the stress prevention programme. The purpose of this dissertation is to analyse the effectiveness of the stress prevention programme and its impacts. Some suggestions of possible improvements within the programme are also mentioned.

Over 16 million people in the US suffer from major depressive disorder (MDD) each year. Approximately 1/3rd of MDD patients (~5 million) obtain only partial remission or no benefit after trials with multiple drugs or drug combinations. Recently, Ordway and colleagues have reportedelevated levels of DNA oxidation and upregulated gene expression of the base excision repair enzyme poly(ADP-ribose) polymerase-1 (PARP1) in postmortem brain from donors who had MDD at the time of death, as compared to age-matched psychiatrically normal control donors. This study was designed to test whether an inhibitor of PARP, 3-aminobenzamide (3-AB), may be effective to alleviate depressive-like behaviors in a rodent model of treatment-resistant depression. Male rats were ip administered lipopolysaccharide (LPS;100ug/kg) daily for 28 days, and administered a chronic unpredictable stressor on each day. All rats were also administered saline, 3-AB (40 mg/kg), or the serotonin-reuptake inhibitor (SSRI) fluoxetine (trade name: Prozac; 10 mg/kg) on each day, approximately 30 min after LPS treatment. During the 28 day period of LPS treatment, animals were behaviorally tested 5 times on sucrose preference (a test of anhedonia). At the end of the 28 day period, rats were behaviorally tested on a test of acute stress, the Porsolt swim test. Results revealed that 3-AB alleviated anhedonia and the response to acute stress in the Porsolt swim test superior to the fluoxetine group, demonstrating the utility of a PARP inhibitor to alleviate depressive-like behavior in this model. In addition, fluoxetine produced a loss of weight which recovered over days, but not to control levels, and 3-AB did not produce this effect. This study shows that PARP inhibitors may be effective in treatment-resistant depression.

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BACKGROUND AND AIMS: Globally, chronic low back pain (CLBP) affects 70-80% of adults at some point in their lives and current treatments are widely unsuccessful in relieving pain. Understanding the underlying neurophysiological (e.g., descending pain inhibition) and biobehavioral (e.g., stress) processes contributing to chronic pain in patients with CLBP is needed for the development of novel treatments. Previous studies have shown that acute stress can impact pain sensitivity and that childhood trauma may predispose a person to CLBP, but the mechanisms underlying this impact are unknown. Conditioned Pain Modulation (CPM) is a psychophysical paradigm used in research to assess descending pain modulatory pathways, which are thought to be impaired in patients with CLBP as well as in those with childhood trauma. The overlap of conditions has not been explored. The current study explored the impact of childhood trauma on the CPM response within a sample of patients with CLBP being treated at a tertiary pain clinic. CLBP patients exposed to an acute stress paradigm were expected to shower higher pain sensitivity, with acute stress significantly interacting with a history of childhood trauma as a factor leading to the higher pain sensitivity. METHODS: 46 Participants with CLBP (n=46, mean age=49 years, 55.3% female) recruited from a pain treatment service completed a Quantitative Sensory Testing (QST) and CPM before and after an acute psychological stressor. Participants were randomized to a control (n=25) or an acute-stress (n=21) condition. The acute-stress condition included the Stroop Color Word Task (SCWT) and a mental arithmetic task prior to completing the QST protocol a second time. The control participants did not undergo any additional stressors and completed the QST protocol a second time after a 20-minute break. Participants’ CPM response was measured by the average change in pressure pain threshold (PPT) from baseline to the conditioning stimulus (non-dominant hand in ice-water bath). A “Good CPM response” was defined as a CPM effect above 100, indicating that the pain threshold increased when exposed to the conditioning stimulus. To examine the impact of childhood trauma on pain sensitivity, participants completed a Childhood Traumatic Events Scale (CTES) to assess the presence and severity of six types of trauma (death, parental upheaval, sexual, violence, illness or injury, other upheaval) during childhood. The CTES was scored as a continuous variable by calculating the sum the trauma severity for all six trauma types. RESULTS: A large majority of the sample (94% of participants) showed an increase in pain threshold during hand immersion in ice water, which was contrary to our hypothesis based on prior research done on other chronic pain conditions and CLBP. Participants exposed to an acute stressor had an impaired CPM effect compared to those that were not exposed to an acute stressor, however there was no difference between groups (p=0.277). A history of childhood traumatic events did not correlate significantly with an impaired baseline CPM or a change in CPM effect when exposed to an acute stressor. CONCLUSION: The current study used novel QST modalities, including CPM, to analyze the interaction between acute and chronic stress on pain sensitivity. Ultimately, this study found that exposure to an acute stressor had a negative effect on CPM, indicating that when under experimental stress participants were more sensitive to pain compared to when they were not under stress, although the findings were not statistically significant. These findings should be further investigated to expand the understanding of the neurophysiological mechanisms underlying CLBP and to potentially provide novel treatment modalities for patients with CLBP.

Tout d’abord, nous avons démontré l’origine périphérique de la corticostérone après l’administration d’un stress aigu. Pour cela, nous avons utilisé un modèle de souris déficient en transporteur de corticostérone : Corticosterone binding-globulin (Cbg-/-). Ensuite, nous avons déterminé si les effets rapides du stress sur le rappel mnésique dépendaient de mécanismes non-génomiques. Nous avons précisé si ces effets étaient médiés par les récepteurs aux minéralocorticoïdes (MR) ou aux glucocorticoïdes de l’hippocampe. Dans ce but dans un premier temps, nous avons injecté un complexe macromoléculaire de corticostérone (Cort-3CMO-BSA) qui ne franchit pas la membrane cellulaire pour évaluer l’implication de mécanismes membranaires. Dans un deuxième temps nous avons administré dans l’hippocampe dorsal (HD) ou ventral (HV), 15 minutes avant le stress, l’antagoniste MR (RU 28318) et l’antagoniste GR (RU 38486) et nous avons évalué les performances mnésiques à 15, 60, 105 et 120 minutes après le stress. En effet ces délais ont été choisis selon l’apparition de pics de corticostérone induit par le stress, mesurés par microdialyse, dans l’HD et l’HV.Les principaux résultats obtenus sont : i) les souris Cbg -/- ne présentent pas de déficit mnésique 15 min après l’administration d’un stress aigu, contrairement aux souris contrôles qui ont un déficit mnésique important; ii) De même, l’administration de métyrapone (un inhibiteur de synthèse de la corticostérone) prévient des effets rapides du stress sur la mémoire; iii) Nous avons démontré que les effets rapides délétères sont médiés par des récepteurs membranaires, puisque l’injection de Cort-3CMO-BSA dans l’HD produit des effets similaires au stress aigu. De plus, l’effet de l’injection du complexe Cort-3CMO-BSA n’est pas bloqué par l’injection systémique d’anisomycine (un inhibiteur de synthèse protéique) nous avons montré que les récepteurs membranaires aux glucocorticoïdes de type MR sont responsables des effets cognitifs rapides du stress et de la cort-3CMO-BSA sur le rappel mnésique ;iv) Dans l’HD, l’injection du RU 28318 bloquait les effets délétères du stress quand les performances mnésiques étaient évaluées 15 min après le stress, mais non aux délais plus longs. Au contraire, le RU 38486 prévenait les déficits mnésiques quand les performances étaient évaluées à 60 mais non à 105 min après le stress. Dans l’HV, le schéma opposé est observé puisque l’injection du RU 38486 est dénuée d’effet quand il est injecté à 60 min après le stress mais il bloque les déficits mnésiques induits 105 min après le stress. L’implication des récepteurs MR et GR et l’efficacité de leur antagoniste semble dépendant de l’évolution de la concentration de corticostérone au cours du temps dans l’HD et l’HV.Pour conclure, notre étude a mis en évidence que le stress aigu diminue le rappel mnésique hipocampo-dépendant par l’intermédiaire d’un mécanisme de “switch” impliquant les récepteurs MR puis GR de l’HD à des délais plus courts et ensuite seulement les récepteurs GR de l’HV à des délais plus long. / We first showed the peripheral origin of corticosterone after an acute stress administration (electric foot-shocks) using corticosterone binding globulin-deficient mice (Cbg -/-). Then, we intended to determine if the rapid effects of stress on memory retrieval depended on non-genomic mechanisms and in a further step to precise whether such effects are mediated by mineralocorticoid (MR) or glucocorticoid receptors (GR) in the hippocampus. To that aims, we first injected a macromolecular complex of corticosterone (Cort-3CMO-BSA) that cannot cross the cell membrane to assess the involvement of membrane mechanisms. In a second step, we injected 15 minutes before stress delivery either in the dorsal (DH) or ventral (VH) hippocampus the MR antagonist (RU 28318) and GR antagonist (RU 38486) and evaluated memory at 15, 60, 105 and 120 minutes after stress delivery. Indeed, these delays were chosen according to the occurrence of stress-induced corticosterone peaks measured by microdialysis in DH and VH.The main results obtained in this study are: i) Cbg -/- mice are not affected by stress delivery occurring 15 minutes before memory testing, in contrast wild-type control mice which exhibited an important memory retrieval deficit; ii) Similarly, the rapid effects of stress on memory could be prevented by the systemic injection of metyrapone (a corticosterone synthesis inhibitor); iii) We showed that the rapid (15min) deleterious of stress on memory are mediated by membrane receptors, since the injection of Cort-3CMO-BSA in the DH produced similar effects as stress delivery. Moreover, the effect of the Cort-3CMO-BSA complex is not blocked by systemic injection of anisomycin (a protein synthesis inhibitor); iv) In DH, the injection of RU 28318 blocked the deleterious effects of stress when testing occurred 15 min after stress but not for longer delays. In contrast, RU 38486 prevented memory retrieval impairments when performance was evaluated at 60 but not at 105 min after stress. In addition, the opposite pattern was observed in VH since RU 38486 was denied of any effects when injected at 60 min but blocked the stress-induced memory impairments at the 105 min post-stress delay. The involvement of MR and GR receptors and consequently the efficiency of their antagonists seem to depend on the time-course evolutions of stress-induced corticosterone rises within the DH and VH.In conclusion, our study evidenced that acute stress impairs hippocampus-dependent memory retrieval via a switch mechanism involving the MR then GR in DH at shorter delays and then only GR in VH at longer delay.

La capacité de ressentir et de réguler les émotions permettant de fournir un comportement émotionnel adapté implique l'intervention et l'interaction du système nerveux central (SNC) (dont amygdale, cortex préfrontal (CPF)) et du système nerveux autonome (SNA). Cependant, les réponses émotionnelles peuvent être influencées par différents facteurs puisque la réponse émotionnelle va dépendre de l'état du sujet, mais également de l'action du sujet, c'est-à-dire de l'intention consciente et volontaire de réguler ses émotions. Cette thèse a donc pour objectif d'étudier les mécanismes physiologiques et cérébraux impliqués dans la variabilité de la réponse émotionnelle en utilisant cinq modèles susceptibles d'influencer la réponse émotionnelle : une tâche de contrôle émotionnel, l'état de stress post traumatique (ESPT), le neuroticisme, la résilience, et l'état de stress aigu. Pour répondre à ces objectifs, nous avons sélectionné trois populations de sujets, une population de sujets témoins, une population de patients atteints d'ESPT, et une population de Marins-Pompiers. Nous avons étudié les réponses du SNA et du SNC en IRMf, en se focalisant sur l'activité de l'amygdale et du CPF dans des tâches nature émotionnelle. Nos résultats indiquent que la régulation émotionnelle volontaire a des effets spécifiques sur les paramètres psychophysiologiques, qui diffèrent selon l'émotion présentée. On observe plus précisément une augmentation de l'activité du système nerveux sympathique uniquement lorsque l'émotion de peur est induite. / The ability to sense and regulate emotions allows us to have an adapted emotional behavior towards our environment. It is regulated by an interaction of the central nervous system (CNS), including the amygdala and prefrontal cortex (PFC), and the autonomic nervous system (ANS). Yet, our emotional responses can be influenced by a myriad of other factors. They depend for instance on ones' subjective state, and also voluntary conscious intention to control one's emotions. The aim of this thesis is thus to study peripheral and cerebral mechanisms involved in the variability of the emotional response. To do so, we have used five different models susceptibly influencing emotional response: a first model assaying healthy controls in an emotional control task, a second one accounting for their resilience capacity, a third one focused on the impact of neuroticism, a fourth one with acutely stress participants and a last one with post-traumatic stress disorder (PTSD) patients. To better address our objective, we have selected three groups of participants: healthy controls, PTSD patients and fire fighters. We explored responses of the the ANS and the CNS activities using fMRI-based paradigms, specifically tackling the activation of the amygdala and PFC; using an emotional tasks. As hypothesized, our results have shown that voluntary emotional regulation in healthy controls modulates physiological parameters in an emotion-specific manner. For instance the sympathetic system is only activated under those circumstance when processing fearful clips.