Caractérisation du Prostate-derived Ets transcription factor (PDEF) comme antigène tumoral candidat des cancers invasifs du sein

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Neuron-Derived Semaphorin 3A is an Early Inducer of Vascular Permeability in Diabetic Retinopathy

La détérioration de la barrière hémato rétinienne et l'oedème maculaire consécutif est une manifestation cardinale de la rétinopathie diabétique (RD) et la caractéristique clinique la plus étroitement associée à la perte de la vue. Alors que l'oedème maculaire affecte plus de 25% des patients souffrant de diabète, les modalités de traitement actuellement disponibles tels que les corticostéroïdes administrés localement et les thérapies anti-VEGF récemment approuvés présentent plusieurs inconvénients. Bien que le lien entre une rupture de l’unité neuro-vasculaire et la pathogénèse de la RD ait récemment été établi, l’influence de la signalisation neuro-vasculaire sur la vasculopathie oculaire diabetique a jusqu’à présent reçu peu d’attention. Ici, à l’aide d’ètudes humaines et animales, nous fournissons la première preuve du rôle essentiel de la molécule de guidage neuronale classique Sémaphorine 3A dans l’instigation de la perméabilité vasculaire maculaire pathologique dans le diabète de type 1. L’étude de la dynamique d’expression de Sémaphorine 3A révèle que cette dernière est induite dans les phases précoces hyperglycèmiques du diabète dans la rétine neuronale et participe à la rupture initiale de la fonction de barrière endothéliale. En utilisant le modèle de souris streptozotocine pour simuler la rétinopathie diabétique humaine, nous avons démontré par une série d’approches analogue que la neutralisation de Sémaphorine 3A empêche de façon efficace une fuite vasculaire rétinienne. Nos résultats identifient une nouvelle cible thérapeutique pour l’oedème maculaire diabétique en plus de fournir d’autres preuves de communication neuro-vasculaire dans la pathogènese de la RD.

Conceptualisation et communication des nuances de timbre à la guitare classique

La version intégrale de cette thèse est disponible uniquement pour consultation individuelle à la Bibliothèque de musique de l’Université de Montréal (www.bib.umontreal.ca/MU).

Utilization of biodiesel-derived glycerol or xylose for increased growth and lipid production by indigenous microalgae

The use of industrial wastes rich in mineral nutrients and carbon sources to increase the final microalgal biomass and lipid yield at a low cost is an important strategy to make algal biofuel technology viable. Using strains from the microalgal collection of the Université de Montréal, this report shows for the first time that microalgal strains can be grown on xylose, the major carbon source found in wastewater streams from pulp and paper industries, with an increase in growth rate of 2.8 fold in comparison to photoautotrophic growth, reaching up to µ=1.1/day. On glycerol, growth rates reached as high as µ=1.52/day. Lipid productivity increased up to 370% on glycerol and 180% on xylose for the strain LB1H10, showing the suitability of this strain for further development for biofuels production through mixotrophic cultivation.

Représentations sociales de la dangerosité psychiatrique chez les intervenants en santé mentale : une anthropologie du risque

Le présent mémoire porte sur les représentations sociales de la dangerosité en psychiatrie chez les intervenants de proximité (infirmières, préposés, et agent de sécurité), d’un milieu de soins psychiatriques. Nous cherchons à explorer comment ces intervenants perçoivent et interprètent les risques inhérents à leur métier et comment ils y réagissent en situation d’incertitude. Les concepts de dangerosité, d’ « individu dangereux » et de risque en psychiatrie sont abordés dans le présent mémoire, à travers un angle historique, social et anthropologique, suivant les lectures de Michel Foucault; de Robert Castel; de Ian Hacking; et de Mary Douglas. De l’observation participante dans une unité de soins psychiatriques aigus et des entrevues semi-structurées ont été réalisées auprès d’une dizaine d’intervenants en santé mentale. Une approche ethnographique et interprétative nous a permis de dégager les principales récurrences, divergences et contradictions intra et inter intervenants sur la question de la dangerosité et du risque en psychiatrie. Les résultats sont séparés en fonction de trois grands thèmes : 1) représentations sociales de la dangerosité 2) perceptions du risque au travail 3) réactions face au risque perçu. L’analyse de nos résultats montre que les connaissances qu’ont les intervenants sur la dangerosité ne se limitent pas à celles produites par le savoir expert, elles s’ouvrent aussi sur leur propre réalité clinique. De plus, contrairement aux prédictions du savoir expert, la différence observée entre les pratiques de contrôle des intervenants n’est pas la conséquence d’une surestimation du risque ni d’un manque d’information « objective » sur les facteurs de risque du comportement agressif, mais s’explique davantage en fonction de la présence ou de l’absence d’un lien thérapeutique et du degré de reconnaissance sociale dans les interactions entre les soignants et les soignés. Les éléments qui renforcent ou limitent l’établissement d’un lien de confiance sont explicités dans le présent mémoire.

The costs of alcohol, illegal drugs, and tobacco in Canada, 2002.

Objective: The aim of this study was to estimate costs attributable to substance use and misuse in Canada in 2002. Method: Based on information about prevalence of exposure and risk relations for more than 80 disease categories, deaths, years of life lost, and hospitalizations attributable to substance use and misuse were estimated. In addition, substance-attributable fractions for criminal justice expenditures were derived. Indirect costs were estimated using a modified human capital approach. Results: Costs of substance use and misuse totaled almost Can. $40 billion in 2002. The total cost per capita for substance use and misuse was about Can. $1,267: Can. $463 for alcohol, Can. $262 for illegal drugs, and Can. $541 for tobacco. Legal substances accounted for the vast majority of these costs (tobacco: almost 43% of total costs; alcohol: 37%). Indirect costs or productivity losses were the largest cost category (61%), followed by health care (22%) and law enforcement costs (14%). More than 40,000 people died in Canada in 2002 because of substance use and misuse: 37,209 deaths were attributable to tobacco, 4,258 were attributable to alcohol, and 1,695 were attributable to illegal drugs. A total of about 3.8 million hospital days were attributable to substance use and misuse, again mainly to tobacco. Conclusions: Substance use and misuse imposes a considerable economic toll on Canadian society and requires more preventive efforts.

Studies On Supported Cobalt (Ii), Nickel (Ii) and Copper (Ii) Complexes Of O-Phenylenediamine and Schiff Bases Derived from 3-Hydroxyquinoxaline-2-Carboxaldehyde

The thesis deals with the synthesis, characterization and catalytic activity studies of supported cobalt(ii), nickel(II) and copper(II) complexes of O-phenylenediamine and Schiff bases derived from 3-hydroxyquinoxaline -2-carboxaldehyde. Zeolite encapsulation and polymer anchoring was employed for supporting the complexes. The characterization techniques proved that the encapsulation as well as polymer supporting has been successfully achieved. The catalytic activity studies revealed that the activities of the simple complexes are improved upon encapsulation. Various characterization techniques are used such as, chemical analysis, EPR, magnetic measurements, FTIR studies, thermal analysis, electronic spectra, XRD, SEM, surface area, and GC.The present study indicated that the that the mechanism of oxidation of catechol and DTBC by hydrogen peroxide is not altered by the change in the coordination sphere around the metal ion due to encapsulation. This fact suggests outer sphere mechanism for the reactions. The catalytic activity by zeolite encapsulated complex was found to be slower than that by the neat complex. The slowing down of the reaction in the zeolite case is probably due to the constraint imposed by the zeolite framework. The rate of DTBC ( 3,5-di-tert-butylchatechol)oxidation was found to be greater than the rate of catechol oxidation. This is obviously due to the presence of electron donating tertiary butyl groups.

Diversity in Structural and Spectural Characteristics of Some Transition Metal Complexes Derived From Aldehyde Based Thiosemicarbazone Ligands

The study deals with the diversity in structural and spectural characteristics of some transition metal complexes derived from aldehyde based thiosemicarbazone ligands thiosemicarbazones are a family of compounds with beneficial biological activity viz., anticancer,antitumour, antifungal, antibacterial, antimalarial, antifilarial, antiviral and anti-HIV activities. Many thiosemicarbazone ligands and their complexes have been prepared and screened for their antimicrobial activity against various types of fungi and bacteria. The results prove that the compounds exhibit antimicrobial properties and it is important to note that in some cases metal chelates show more inhibitory effects than the parent ligands. The increased lipophilicity of these complexes seems to be responsible for their enhanced biological potency. Adverse biological activities of thiosemicarbazones have been widely studied in rats and in other species. The parameters measured show that copper complexes caused considerable oxidative stress and zinc zinc complexes behaved as antioxidants. It has applications on analytical field also. Some thiosemicarbazones produce highly colored complexes with metal ions. This thesis aims to synthesis some novel thiosemicarbazone ligands and their transition metal complexes together with their physico-chemical characterization.

Studies on Some Simple and Zeolite-Y Encapsulated 3d-Transition Metal Complexes of Schiff Bases Derived From 2-Aminobenzothiazole

In this regard Schiff base complexes have attracted wide attention. Furthermore, such complexes are found to play important role in analytical chemistry, organic synthesis, metallurgy, refining of metals, electroplating and photography. Many Schiff base complexes are reported in literature. Their properties depend on the nature of the metal ion as well as on the nature of the ligand. By altering the ligands it is possible to obtain desired electronic environment around the metal ion. Thus there is a continuing interest in the synthesis of simple and zeolite encapsulated Schiff base complexes of metal ions. Zeolites have a number of striking structural similarities to the protein portion of natural enzymes. Zeolite based catalysts are known for their remarkable ability of mimicking the chemistry of biological systems. In view of the importance of catalysts in all the areas of modern chemical industries, an effort has been made to synthesize some simple Schiff base complexes, heterogenize them by encapsulating within the supercages of zeoliteY cavities and to study their applications. The thesis deals with studies on the synthesis and characterization of some simple and zeoliteY encapsulated Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) complexes and on the catalytic activity of these complexes on some oxidation reactions. Simple complexes were prepared from the Schiff base ligands SBT derived from 2-aminobenzothiazole and salicylaldehyde and the ligand VBT derived from 2-aminobenzothiazole and vanillin (4-hydroxy-3- methoxybenzaldehyde). ZeoliteY encapsulated Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) complexes of Schiff base ligands SBT and VBT and also of 2-aminobenzothiazole were synthesized. All the prepared complexes were characterized using the physico-chemical techniques such as chemical analysis (employing AAS and CHN analyses), magnetic moment studies, conductance measurements and electronic and FTIR spectra. EPR spectra of the Cu(II) complexes were also carried out to know the probable structures and nature of Cu(II) complexes. Thermogravimetric analyses were carried out to obtain the information regarding the thermal stability of various complexes. The successful encapsulations of the complexes within the cavities of zeoliteY were ascertained by XRD, surface area and pore volume analysis. Assignments of geometries of simple and zeoliteY encapsulated complexes are given in all the cases. Both simple and zeoliteY encapsulated complexes were screened for catalytic activity towards oxidation reactions such as decomposition of hydrogen peroxide, oxidation of benzaldehyde, benzyl alcohol, 1-propanol, 2-propanol and cyclohexanol.

Two novel bis-azomethines derived from quinoxaline-2-carbaldehyde

The Schiff base compounds N,N0-bis[(E)-quinoxalin-2-ylmethylidene] propane-1,3-diamine, C21H18N6, (I), and N,N0-bis[(E)- quinoxalin-2-ylmethylidene]butane-1,4-diamine, C22H20N6, (II), crystallize in the monoclinic crystal system. These molecules have crystallographically imposed symmetry. Compound (I) is located on a crystallographic twofold axis and (II) is located on an inversion centre. The molecular conformations of these crystal structures are stabilized by aromatic pye stacking interactions.

A novel fluorescent bisazomethine dye derived from 3-hydroxyquinoxaline-2- carboxaldehyde and 2,3-diaminomaleonitrile

A novel bisazomethine Schiff base was synthesised by the condensation of 3-hydroxyquinoxaline-2- carboxaldehyde and 2,3-diaminomaleonitrile. 1H NMR, 13C NMR, HPLC and FT-IR studies revealed that the compound exists in two major tautomeric forms. The Schiff base exhibits positive absorption and fluorescent solvatochromism and displays dual fluorescence with large stoke shifts. Cyclic voltammetric analysis of the compound in 1:1 methanol–THF was influenced by scan rate. Thermal analysis of the compound was undertaken using TG–DTA and DSC

Studies on Some Transition Metal Complexes of Schiff Bases Derived from Quinoxaline-2-carboxaldehyde

Two series of transition metal complexes of Schiff bases derived from quinoxaline-2-carboxaldehyde with semicarbazide (QSC) and furfurylamine (QFA) were synthesised and characterised by elemental analyses, molar conductance and magnetic susceptibility measurements, IR, electronic and EPR spectral studies. The QSC complexes have the general formula [M(QSC)Cl2]. A tetrahedral structure has been assigned for the Mn(II), Co(II) and Ni(II) complexes and a square-planar structure for the Cu(II) complex. The QFA complexes have the formula [M(QFA)2Cl2]. An octahedral structure has been assigned for these complexes. All of the complexes exhibit catalytic activity towards the oxidation of 3,5-di-tert-butylcatechol (DTBC) to 3,5-di-tert-butylquinone (DTBQ) using atmospheric oxygen. The cobalt(II) complex of the ligand QFA was found to be the most active catalyst.

Synthesis and Characterization of Some New Transition Metal Complexes of the Schiff Base Derived from Quinoxaline-2-Carboxaldehyde and 2- Aminophenol

Some new transition metal complexes of the Schiff base quinoxaline-2-car boxalidene-2-aminophenol (HQAP) have been synthesized and characterized by elemental analyses, conductance and magnetic measurements and IR and UV-Visible spectral studies. The complexes have the following empirical formulae: [Mn(QAP121, [Fe(QAPl2C1I, [Co(QAPl21, [Ni(QAP121 and [Cu(QAP121. A tetrahedral structure has been assigned for the manganese(=), cobalt(II1, nickel(II1 and copper(II1 complexes. For the iron(IIIl complex an octahedral dimeric structure has been suggested