Mécanismes impliqués dans le développement du remodelage eutrophique des artères de résistance et du coeur dans un modèle d'hypertension induite par l'inhibition de la synthèse du NO

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.

Dépistage de la résistance à l'aspirine chez les patients coronariens stables, suivis à la clinique externe de cardiologie de l'Hôpital du Sacré-Coeur de Montréal

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Voyage au coeur de la prédation entre vendeurs et acheteurs : une nouvelle théorie en vente et marketing

Résumé : II existe une tension inhérente au sein de la relation en cours de développement entre un vendeur et un acheteur. Le vendeur craint que l'acheteur lui fasse perdre son temps et l'acheteur, lui, doute de l'honnêteté du vendeur. Tous deux s'interrogent sur le niveau de confiance et de coopération à accorder à l'autre. Il est possible, après tout, que le vendeur soit à l'affût de la moindre faiblesse de l'acheteur pour profiter de la situation et s'enrichir à ses dépens, ou, vice-versa, que l'acheteur cherche à profiter du vendeur. La présente thèse examine les tensions entre vendeurs et acheteurs en ayant recours à la théorie enracinée élargie, qui comprend une série de boucles investigatrices formées de revues des écrits scientifiques et de cueillettes de données qualitatives et quantitatives. Elle cherche à démontrer que la prédation perçue (l'impression que l'autre abuse de nous de manière coordonnée) affecte négativement la bonne entente entre les parties prenantes de la transaction. La thèse suggère aussi que le phénomène de prédation existe dans toutes les sphères d'activités humaines, y compris dans le domaine juridique. Le modèle PARDU (prédateur-proie) initialement développé pour discuter du phénomène de prédation débouche, au fil de la recherche, sur le modèle OPERA et la grille MESLY®, qui offrent des applications pratiques pour mieux gérer la prédation informationnelle.||Abstract : There is an inherent tension between a seller and a buyer as their relationship progresses towards closing the deal. The salesperson fears that the buyer wastes his time, which he could otherwise spend towards real potential buyers. The buyer questions the sincerity of the salesperson. Both evaluate the amount of trust and coopération they should invest in the relationship. It is possible, after ail, that the salesperson wants to take advantage of every weakness he detects in the buyer in order to guarantee the sale, and it is equally possible that the buyer tries to fool the salesperson, with false credit information for example. This thesis examines tensions that exist between salespeople and buyers by using an extended version of grounded theory, by which date is collected and analysed both qualitatively and quantitatively. It demonstrates that perceived prédation reduces considerably the quality of the relationship. The thesis suggests that the phenomenon of prédation exists in every sphere of human activity, including in the légal system. The PARDU Model (predator-prey) initially developed to discuss the phenomenon of predation evolves, as the research progresses, towards the OPERA Model and the MESLY® grid, which offer pratical tools to better manage informational predation.

Modélisation de la dispersion chromatique et de l’atténuation dans les fibres microstructurées à coeur suspendu

D’abord, nous présentons les principes physiques nous permettant de modéliser et comprendre le phénomène de propagation linéaire des impulsions lumineuses dans un milieu homogène, dans les guides d’ondes planaires et enfin dans les fibres optiques microstructurées. Ensuite, nous faisons une analyse mathématique rigoureuse des équations linéaires de propagation et posons le problème comme celui de la recherche de valeurs propres d’opérateurs auto-adjoints dans un espace de Hilbert. On verra que ces résultats théoriques s’appliquent aux équations simulées dans le logiciel Comsol Multiphysics. Enfin, nous recensons et proposons différentes façons de prédire les valeurs de dispersion chromatique et d’atténuation dans les fibres microstructurées à coeur suspendu en utilisant les notions et équations discutés dans les deux premiers chapitres. Le choix de la géométrie, du matériau et de la longueur d’onde de la lumière transmise sont parmi les variables étudiées numériquement. Nous ferons également un exemple détaillé d’utilisation du logiciel Comsol Multiphysics pour construire un modèle de fibre optique microstructurée.

La famille, l'amitié et les relations amoureuses au coeur du traitement des jeunes qui présentent un trouble lié à l'utilisation d'une substance et qui sont placés en mise sous garde dans un centre jeunesse

Ce projet de mémoire, de nature exploratoire, examine la place que pourraient occuper la famille, les amis et les relations amoureuses dans le traitement pour un trouble lié à l’utilisation d’une substance (TUS) chez des jeunes qui participent ou qui ont participé, au cours des deux dernières années, au programme toxico-justice jeunesse. Ce programme est offert par le Centre de réadaptation en dépendance de Québec (CRDQ) et s’adresse aux jeunes qui présentent un TUS et qui sont placés dans une unité de mise sous garde du Centre jeunesse de Québec (CJQ). Pour rencontrer le principal objectif de la recherche, l’importance qu’octroient les jeunes aux relations familiales, amoureuses et d’amitié 1) dans leur parcours de consommation et 2) dans leur processus de rétablissement a été étudiée. Au total, 11 jeunes ont été rencontrés et interviewés par le biais d’entrevues semi-structurées. L’analyse des données qualitatives suggère que les relations familiales, amicales et amoureuses ont une importance considérable dans la compréhension du parcours de consommation et de rétablissement des jeunes consommateurs placés en mise sous garde du CJQ. Donc, nos résultats soutiennent qu’il serait bénéfique de tenir compte de ces relations dans le traitement de cette clientèle. Toutefois, une attention plus particulière devrait, selon nous, être portée à la famille de ces jeunes en cours de traitement. En effet, nos résultats suggèrent que les relations familiales sont celles qui ont le plus de poids dans le parcours de consommation et de rétablissement des jeunes. En fait, plus les jeunes se sentent soutenus par leur famille durant leur placement en mise sous garde, plus ils sont susceptibles de désirer délaisser leurs amis consommateurs et leurs activités illicites. Nous croyons donc qu’il serait important, pour cette clientèle, de traiter les relations familiales en priorité, tout en considérant les relations d’amitié et amoureuses en cours d’intervention. Trois idéaux types familiaux se dégagent de nos travaux. Des modalités de traitement ont donc été développées en fonction de chacun de ces idéaux types. Ces modalités de traitement seront décrites dans la discussion du présent mémoire.

Le débat entre le coeur et le devoir dans : La Princesse de Clèves

Ce mémoire traite du débat entre le coeur et le devoir et des différentes influences qui ont conduit à la fameuse question : Pourquoi la princesse n’épouse-t-elle pas le duc de Nemours alors que tous les obstacles sont levés ? À défaut de pouvoir répondre définitivement à cette énigme dont seule Madame de La Fayette possède la clé, nous nous sommes concentrée sur les influences qui auraient pu pousser la princesse à sacrifier son coeur pour son devoir. La méthode de recherche utilisée est l’approche de la biographie intellectuelle. Il est évident que le vécu de l'auteure a teinté le contenu de son oeuvre ainsi que l'âme de son héroïne. Nous nous sommes également inspirée de la méthode sociocritique quant aux influences et mouvements de l'époque. Dans le but de simplifier la collecte des sources et l’organisation de la recherche, nous avons regroupé les influences en trois grandes catégories : les influences personnelles, internes et externes. Cette étude a mis en évidence que les moeurs, dans La Princesse de Clèves, sont le miroir de la société du XVIIe siècle. Chaque influence présentée forme le dessin d’une princesse cachant en elle le secret de son renoncement à l'amour.

Flaubert e o crepúsculo do sujeito: uma análise do conto "Um coração simples"

A literatura francesa e mundial passaram por uma enorme transformação ao longo do século XIX. A primorosa escrita de Flaubert é, para além de sua importância estética, reveladora de um novo modo de se escrever, ler e representar o homem no mundo moderno. O cuidado na construção do texto, a utilização de imagens plásticas e figuras de linguagem, ao mesmo tempo em que o narrador torna-se invisível no emprego do discurso indireto livre são característicos da escrita flaubertiana. O autor apresenta-nos em "Um coração simples" um "retrato" de Félicité, mulher pobre do interior da França, modelo virtuoso de uma ética evanescente. Ao acompanhar, por meio do conto, os passos e desventuras de Felicité, sob as lentes deste novo narrador, buscamos evidenciar as condições que circundam o aparecimento de um olhar científico-objetivo para a subjetividade humana, logo transformada em objeto de uma nascente Psicologia.

Heavy Metal Contamination in Phrynops geoffroanus (Schweigger, 1812) (Testudines: Chelidae) in a River Basin, So Paulo, Brazil

The Piracicaba River basin is considered the most disturbed river basin in the state of So Paulo. Considerable amounts of agricultural residues are seasonally drained into the river, and the region is also highly urbanized and industrialized with an incipient sewage treatment system. The presence of heavy metals has been previously reported for the water and riverbed in Piracicaba river basin. In this study we evaluated 13 heavy metals in the blood of 37 Geoffroy`s side-necked turtles, Phrynops geoffroanus, from Piracicaba River and Piracicamirim Creek, one of its tributaries. Blood levels of As, Co, Cr, Se and Pb varied among sites, whereas Sn varied between males and females. However, no obvious pathology was detected. Serum level of Cu (2,194 ng g(-1)) and Pb (1,150 ng g(-1)) found in this study are the highest ever described for any reptile; however, no clinical symptoms have been detected in the present study. There is no information about the time scale of such contamination, which could be currently subclinical and yet lead to a breakdown in the population reproductive success in a few years. Based on the present study, legal enforcement is urged in order to locate and extirpate heavy metal sources in the Piracicaba River basin. In addition, monitoring should include humans and commercial fish consumed in local markets.

Assessment of how pregnancy modifies plasma lead and plasma/whole blood lead ratio in ALAD 1-1 genotype women

Pregnant women are one of the most sensitive populations to the toxic effects associated with lead (Pb) exposure. These effects are primarily associated with plasma Pb (Pb-P), which reflects the most rapidly exchangeable fraction of Pb in the bloodstream, and elevated maternal Pb-P may be more relevant to foetal Pb exposure than whole blood Pb (Pb-B). We investigated how pregnancy affects Pb-B, Pb-P and %Pb-P/Pb-B ratios without the influence of the 6-aminolevulinic acid dehydratase (ALAD) G177C polymorphism, which is a major genetic factor influencing Pb-B, Pb-P and %Pb-P/Pb-B ratios. Genotypes for the ALAD G177C polymorphism were determined by PCR and restriction fragment length digestion in nine pregnant and 20 non-pregnant women, aged 18-33, environmentally exposed to Pb. Here, we included only women with ALAD 1-1 genotype. Pb-P and Pb-B were determined by inductively coupled plasma mass spectrometry and by graphite furnace atomic absorption spectrometry, respectively. We found no differences in Pb-B (P > 0.05). However, pregnant women had a 2-fold increase in Pb-P and a 3-fold increase in %Pb-P/Pb-B (both P < 0.01) compared to nonpregnant women. These alterations in Pb concentrations associated with pregnancy are similar to those associated with different ALAD gene variants. We can now better appreciate how pregnancy affects foetal exposure to Pb without the influence of this important genetic factor.

Public health implications of new guidelines for lead in drinking water: a case study in an area with historically high water lead levels

Concern about the neurotoxicity of lead, particularly in infants and young children, has led to a revision of blood lead levels which are considered to involve an acceptable level of human exposure. Drinking water guidelines have also been reviewed in order to reduce this source of population exposure to lead. In the last 20 years, guidelines have been reduced from 100 to 50 to 10 mu g/litre. Lead in tap water used to be a major public health problem in Glasgow because of the high prevalence of houses with lead service pipes, the low pH of the public water supply and the resulting high levels of lead in water used for public consumption. Following two separate programmes of water treatment, involving the addition of lime and, a decade later, lime supplemented with orthophosphate, it is considered that maximal measures have been taken to reduce lead exposure by chemical treatment of the water supply. Any residual problem of public exposure would require large scale replacement of lead service pipes. In anticipation of the more stringent limits for lead in drinking water, we set out to measure current lead exposure From tap water in the population of Glasgow served by the Loch Katrine water supply. to compare the current situation with 12 years previously and to assess the public health implications of different limits. The study was based on mothers of young children since maternal blood lead concentrations and the domestic water that mothers use to prepare bottle feeds are the principal sources of foetal and infant lead exposure. An estimated 17% of mothers lived in households with tap water lead concentrations of 10 mu g/litre (the WHO guideline) or above in 1993 compared with 49% in 1981. Mean maternal blood lead concentrations fell by 69% in 12 years. For a given water lead concentration, maternal blood lead concentrations were 67% lower. The mean maternal blood lead concentration was 3.7 mu g/litre in the population at large, compared with 3.3 mu g/litre in households with negligible or absent tap water lead. Nevertheless, between 63% and 76% of cases of mothers with blood lead concentrations of 10 mu g/dl or above were attributable to tap water lead. The study found that maternal blood lead concentrations were well within limits currently considered safe for human health. About 15% of infants may be exposed via bottle feeds to tap water lead concentrations that exceed the WHO guideline of 10 mu g/litre. In the context of the health and social problems which affect the well-being and development of infants and children in Glasgow, however, current levels of lend exposure are considered to present a relatively minor health problem. (C) 2000 Elsevier Science Ltd. All rights reserved.

Finger and A-B ridge count, and fluctuating asymmetry in psychosis: A catchment area case-control study

Dermatoglyphic measures are of interest to schizophrenia research because they serve as persistent markers of deviant development in foetal life. Several studies have reported alterations in A–B ridge counts, total finger ridge counts and measures related to asymmetry in schizophrenia. The aim of this study was to assess these measures in an Australian catchment area, case-control study. Individuals with psychosisŽns246.were drawn from a catchment-area prevalence study, and well controlsŽns229. were recruited from the same area. Finger and palm prints were taken usingan inkless technique and all dermatoglyphic measures were assessed by a trained rater blind to case status. The dermatoglyphic measures Žfinger ridge count, A–B ridge count, and their derived asymmetry measures. were divided into quartiles based on the distribution of these variables in controls. The main analysis Žlogistic regression controlled for age and sex.examined all psychotic disorders, with planned subgroup analyses comparing controls with Ž1. nonaffective psychosis Žschizophrenia, delusional disorder, schizophreniform psychosis, atypical psychosis.andŽ2. affective psychosis Ždepression with psychosis, bipolar disorder, schizoaffective psychosis.. There were no statistically significant alterations in the odds of havinga psychotic disorder for any of the dermatoglyphic measures. The results did not change when we examined affective and nonaffective psychosis separately. The dermatoglyphic features that distinguish schizophreniar psychosis in other studies were not identified in this Australian study. Regional variations in these findings may provide clues to differential ethnicrgenetic and environmental factors that are associated with schizophrenia. The Stanley Foundation supported this project.

46,XY DSD due to impaired androgen production

Disorders of androgen production can occur in all steps of testosterone biosynthesis and secretion carried out by the foetal Leydig cells as well as in the conversion of testosterone into dihydrotestosterone (DHT). The differentiation of Leydig cells from mesenchymal cells is the first walk for testosterone production. In 46,XY disorders of sex development (DSDs) due to Leydig cell hypoplasia, there is a failure in intrauterine and postnatal virilisation due to the paucity of interstitial Leydig cells to secrete testosterone. Enzymatic defects which impair the normal synthesis of testosterone from cholesterol and the conversion of testosterone to its active metabolite DHT are other causes of DSD due to impaired androgen production. Mutations in the genes that codify the enzymes acting in the steps from cholesterol to DHT have been identified in affected patients. Patients with 46,XY DSD secondary to defects in androgen production show a variable phenotype, strongly depending of the specific mutated gene. Often, these conditions are detected at birth due to the ambiguity of external genitalia but, in several patients, the extremely undervirilised genitalia postpone the diagnosis until late childhood or even adulthood. These patients should receive long-term care provided by multidisciplinary teams with experience in this clinical management. (C) 2009 Elsevier Ltd. All rights reserved.

Spatial learning ability of rats following differing levels of exposure to alcohol during early postnatal life

Rats exposed to a relatively high dose (7.5 g/kg body weight) of alcohol on either the fifth or tenth postnatal day of age have been reported to have long-lasting deficits in spatial learning ability as tested on the Morris water maze task. The question arises concerning the level of alcohol required to achieve this effect. Wistar rats were exposed to either 2, 4 or 6 g/kg body weight of ethanol administered as a 10% solution. This ethanol was given over an 8-h period on the fifth postnatal day of age by means of an intragastric cannula. Gastrostomy controls received a 5% sucrose solution substituted isocalorically for the ethanol. Another set of pups raised by their mother were used as suckle controls. All surgical procedures were carried out under halothane vapour anaesthesia. After the artificial feeding regimes all pups were returned to lactating dams and weaned at 21 days of age. The spatial learning ability of these rats was tested in the Morris water maze when they were between 61-64 days of age. This task requires the rats to swim in a pool containing water made opaque and locate and climb onto a submerged platform. The time taken to accomplish this is known as the escape latency. Each rat was subjected to 24 trials over 3 days of the test period. Statistical analysis of the escape latency data revealed that the rats given 6 g/kg body weight of ethanol had significant deficits in their spatial learning ability compared with their control groups. However, there was no significant difference in spatial learning ability for the rats given either 2 or 4 g/kg body weight of ethanol compared with their respective gastrostomy or suckle control animals. We concluded that ethanol exposure greater than 4 g/kg over an 8-h period to 5-day-old rats is required for them to develop long-term deficits in spatial learning behaviour. (C) 1998 Elsevier Science Inc.

In utero exposure to air pollution lowers erythrocyte antioxidant defense and decreases weight in adult mice

In this study, we tested the influence of ambient air pollution on different phases of development of adult mice. With respect to adult weight, the animals that had spent their in utero period exposed to pollution showed less weight gain over their lifetime, as well as lower activity levels of the antioxidant enzymes catalase, superoxide dismutase (SOD) and glutathione peroxidase (GPx). Our study suggests that contact with atmospheric pollutants during the foetal period produces important changes on enzymatic erythrocyte antioxidant defense and weight in adult mice. (C) 2011 Elsevier B.V. All rights reserved.

The frequency of anti-beta(2)-glycoprotein I antibodies is low and these antibodies are associated with pulmonary hypertension in mixed connective tissue disease

The objective of this study is to evaluate the prevalence of antiphospholipid antibodies, mainly anti-beta(2)-glycoprotein I (anti-beta(2)-GPI), and their possible clinical and laboratory relevance in mixed connective tissue disease (MCTD). This study included 39 consecutive patients with MCTD (Kasukawa`s criteria) from January, 2005, to March, 2007, and compared them with 21 age- and sex-matched healthy controls. IgG and IgM anticardiolipin (aCL) and anti-beta(2)-GPI were measured by ELISA. Lupus anticoagulant (LA) was detected by functional coagulation tests. Medium to high titres of aCL and anti-beta(2)-GPI antibodies were found in sera from four (10.2%) MCTD patients. One of these patients was found to be positive for IgM aCL, IgM anti-beta(2)-GPI and LA antibodies simultaneously. Additionally, this patient had a previous history of foetal loss in the second trimester and new-onset pulmonary arterial hypertension (PAH). The other three patients had none of the manifestations of antiphospholipid syndrome (APS) or PAH. The mean value of IgG anti-beta(2)-GPI was higher among those MCTD patients with PAH than in the group without PAH (34.2 +/- 46.8 vs 12.3 +/- 9.1, P = 0.018). None of the controls were positive for antiphospholipid antibodies. High to moderate titres of anti-beta(2)-GPI as well as APS were rare in MCTD, and these antibodies may be correlated with the development of PAH in these patients. Lupus (2009) 18, 618-621.