NCube/papyrus huggingface dataset:
Rôle de la molécule CD47 sur le lymphocyte T dans la régulation de la réponse immunitaire

Nowadays, the importance of natural regulatory T cells and adaptive regulatory T lymphocytes in immune regulation and resolution of inflammation are well established. We report a previously unknown pathway to generate adaptive regulatory T cells in the periphery from naive and memory human CD4+CD25- T cells. We show that the stimulation of the broadly expressed transmembrane proteins CD47 on T cells by a monoclonal antibody or by the 4NK1 peptide (carboxy-terminal peptide of thrombospondin-1 (TSP) specific of the binding site of CD47) induced regulatory T cells that exerted an inhibitory function on effector T cells. Our study on the suppressive proprieties of the TSP corroborates with reported anti-inflammatory activities of this extracellular matrix protein. The suppressive function of TSP induced regulatory T cells was contact-dependent and TGF--independent.   Our data further demonstrate the role of CD47 expression on T cells in the antigenic-specific immune response in vivo. We report that the CD47-deficient BALB/c mice displayed a Th1-biased antibody and cytokine responses, instead of the Th2 cytokine profile observed in unmanipulated BALB/c mice. Our study outlines the role of CD47 as a self-control mechanism to negatively regulate type 1 cellular and humoral immune responses and most importantly confirm in vivo previous in vitro studies with human CD4+ T cells.   We also report that soluble anti-CD28 monoclonal antibody suppressed in vitro differentiation of naïve CD4+ T cells isolated from BALB/c mice into IL-17-producing cells by mechanism that are IL-2 and IFN-γ-dependent but independent of the presence of regulatory T cells.   Our studies highlight the suppressive function of two transmembrane molecules CD47 and CD28 expressed by CD4+ T cells in vitro and in vivo in human and mice. They thus may contribute to a better understanding of the mechanisms involved in the induction of immune tolerance, the resolution of inflammation and the differentiation of the T helper cells.

Keyphrases: CD47, CD47, Thrombospondines, Thrombospondins, Regulatory T cells, CD28, CD28, Inflammation, Inflammation, T cell, CD4, CD4, Interleukine-17, Interleukin-17, Immunorégulation, Immunoregulation
Les caractéristiques des amis comme facteurs de risque et de protection associés à la victimisation par les pairs à l’adolescence: une perspective longitudinale

This study examined the association between friend’s characteristics and the pattern of changes in peer victimization in the first years of middle school. The sample was composed of 524 grade 7 and 8  French-Canadian students from two middle schools. Student’s level of victimization as perceived by their peers was evaluated during two consecutive school years. Individual risk factors (i.e. aggressive behaviors, social withdrawal and peer rejection) and friend’s characteristics (i.e. friend’s aggression, social withdrawal and victimization) were also measured with peer nominations during the first year of the study. Results show that beyond individual risk factors, the number of friends was associated with a decrease over time in peer victimization. Moreover, for socially rejected students, having friends who are victimized within the peer group was associated with an increase in peer victimization. Results also show that having aggressive friends lead to a decrease in peer victimization, but only for popular students. However, for socially-rejected students, having aggressive friends was associated with an increase over time in peer victimization. This study brings a new light on the dynamic influences between friends’ identity and the social context in which adolescents evolve.

Keyphrases: Peer victimization, Peer rejection, Aggression, Friendship, Friends’ characteristics, Longitudinal study
Les figures de la lecture dans La possibilité d'une île de Michel Houellebecq

In this thesis, I will study the readings represented in the works of Michel Houellebecq. My work will be separated in two parts. Firstly, I will study the figures of the readers in La possibilité d’une île and in the other novels by Houellebecq. I will then see how the readings are represented in the novels and what are the functions of these character-readers. For example, I will observe how the characters talk about literature in La possibilité d’une île. I will use the concepts of “liseur”, “lu”, and “lectant” established by Michel Picard in La lecture comme jeu, but in the sense of Marcel Goulet’s works. The second part will be centered on another reader who is important: Houellebecq himself. To do so, I will use the theory of the intertextuality of Gérard Genette’s Palimpsestes, which means that I will focus on the explicit traces of other texts in La possibilité d’une île. I will first concentrate my study on the most quoted authors, those that Houellebecq admires or dislikes. Then, I will question myself about the fact that Houellebecq has most of the time a negative relationship with past authors and books – I will try to prove that my author wants the reader to adopt the same kind of criticism towards literature than him. This part will serve to identity what Pierre Bayard calls the author’s “bibliothèque intérieure” (inner library) and to understand his relationship towards it.

Keyphrases: French contemporary  novel, Michel Houellebecq, Michel Houellebecq, Lecture, Reading, Intertextuality
Régulation de l'activité transcriptionnelle de PPARgamma via l'activation des récepteurs CD36 et GHS-R1a : potentiel anti-athérosclérotique

Growth hormone-releasing peptides (GHRPs) are a class of small synthetic peptides known to stimulate GH release through their binding to a G protein-coupled receptor identified as GHS-R1a, later recognized as the ghrelin receptor. Ghrelin is an acetylated 28 amino acid hormone initially identified from the stomach, which induces the release of growth hormone (GH) from the pituitary but also regulates food intake, energy homeostasis, cardiovascular function, immune system and cell proliferation. In documenting the peripheral distribution of GHRPs binding sites, we uncovered the presence of another binding site for GHRPs, identified as CD36, a class B scavenger receptor. CD36 is expressed among several tissues, including myocytes, endothelial cells of the microvasculature and monocytes/macrophages. The macrophage CD36 contributes to excessive lipid loading and atherogenic formation of foam cells through uptake of oxidized low-density lipoprotein (oxLDL) in the subendothelial space of the artery. The properties of hexarelin, a ligand for GHS-R1a and CD36, which features overlapping binding sites with that of oxLDL binding domain on CD36, and thus interfering with the binding of oxLDL on CD36, have prompted us to evaluate the potential of hexarelin, as well as that of the endogenous ligand ghrelin in the modulation of macrophage cholesterol metabolism.  We demonstrate here the ability of hexarelin and ghrelin to enhance the expression of ATP-binding cassette A1 and G1 transporters through a PPARγ-dependent mechanism. The hormone binding domain of PPARγ is not required to mediate PPARγ transcriptional activation by CD36 and GHS-R1a. Both hexarelin and ghrelin promotes phosphorylation of PPARγ in THP-1 macrophages. A more detailed study of GHS-R1a-initiated signaling revealed an intricate and complex signalling interplay triggered by ghrelin that involves modulation of Src-dependent Dok-1/ERK1/2 and Src-independent Gαq/PI3-K/Akt pathways, leading to PPARγ-dependent transcriptional competence in the macrophages. The central role of PPARγ on cholesterol metabolism in the macrophages has been demonstrated using peritoneal macrophages from PPARγ heterozygote mice whose response to hexarelin on PPARγ-LXRα-ABC transporters pathway was strongly impaired. Treatment of apolipoprotein E-null mice fed on a lipid-rich diet with hexarelin resulted in a significant reduction in atherosclerotic lesions, concomitant with an enhanced expression of PPARγ and LXRα target genes in peritoneal macrophages. The results presented in this thesis feature novel mechanisms by which the beneficial regulation of PPARγ and cholesterol metabolism in macrophages could be regulated by both CD36 and ghrelin receptor. The downstream effects following the activation of these receptors might be potential targets in the treatment of human coronary artery disease.

Keyphrases: Atherosclerosis, Fyn kinase, GHS-R1a, Hexarelin, PPARgamma, MAPK/ERK, Akt, ABC transporter, Ghrelin, CD36
Thérapie par les cellules souches mésenchymateuses dans la guérison tendineuse chez le cheval

In equine athletes, tendinitis lesions are common and lead to substantial financial losses. Bone marrow (BM) mesenchymal stem cells (MSCs) are employed clinically empirically to enhance healing of musculoskeletal injuries. However, there is a need to standardize equine MSC isolation protocols, to analyze the effects of MSCs on tendon healing and to optimize dosage. The objectives of the study were to compare 3 methods of equine MSC isolation and develop a minimally invasive model of tendon healing to analyze the effects of MSCs on tendon healing. BM MSCs from the sternum of mares were isolated by 3 protocols (adherence to a plastic culture dish (Classic) and two gradient density separation protocols (Percoll and Ficoll)) to compare for cell viability, MSC yield, number of MSCs attained after 14 days of culture and functional characteristics (self-renewal and multilineage differentiation) of the MSCs. The results suggested that the Percoll protocol was the best of those assessed in terms of MSC yield and self-renewal potential and that MSCs retrieved with the Ficoll protocol had the lowest self-renewal. There were no significant differences in terms of cell viability and differentiation capacity. A tendon healing model was then developed and consisted of a 0.5 cm tenectomy of the lateral digital extensor tendon. However, interanimal variation of healing quality was so high within the pilot group that the model should be re-evaluated. Further studies using MSCs isolated with Percoll in other novel models of tendon healing would allow determination of the adequate dosage of MSCs.

Keyphrases: Percoll, Ficoll, Horse, Tendon healing, Mesenchymal stem cell, Isolation protocol, Percoll, Ficoll
Synthèse stéréosélective de dérivés pipéridines polysubstitués par fragmentation de Grob

This thesis discusses the formation of piperidine derivatives using the Grob fragmentation. Firstly, an introduction of the important alkaloid family as well as previous work completed by the Charette group towards the synthesis of these compounds will be demonstrated. This will be followed by a summary of the Grob fragmentation including a discussion of the reaction conditions, molecular structures, stereoelectronic requirements and modifications of the Grob fragmentation.  Chapter 2 will be dedicated to the development of the methodology and more precisely, to the optimization of all parameters necessary to the reaction. Furthermore, the scope of the reaction and some explanation of the regioselectivity and the diastereoselectivity of the reaction will be discussed.   The developed methodology can be used in a total synthesis and will be demonstrated in Chapter 3. Moreover, using the frangomeric effect concept, a mechanistic study on the Grob fragmentation will be discussed.   Finally, some future projects, especially possible improvement of the methodology, will be presented in the last chapter. This is followed by a conclusion and a summary of the work completed on this project.

Keyphrases: Fragmentation, Grob, Piperidine derivatives, Grignard reagents
H.P. Lovecraft : étude comparative de récits des origines

Throughout the 20th century and until now, the different Lovecraft commentators have agreed on one point: the originality of his oeuvre. Impossible to pigeonhole in a specific literary genre, and open to many layers of interpretation, it has been analysed both from a psychoanalytic angle and from a philosophical and scientific angle. However, the purely aesthetic dimension seems to have been forgotten, possibly through negligence. This dissertation proposes an investigation of the aesthetic aspect of Lovecraft’s oeuvre. Our research hypothesis rests on the obvious, yet rarely elaborated upon by critics, analogies between it and the cosmogonical aesthetics in Antiquity.      First, we shall position Lovecraft’s work within its literary context, e.g. by establishing its evident connection to such authors as J.R.R. Tolkien and Arthur Conan Doyle, but also by underlining the subtler differences that distinguish it from other writers such as H.G. Wells and William Hope Hodgson.       Then, we will put into perspective the elements that logically separate it from Hebrew cosmogony and from the theological and philosophical tradition it inaugurates, as crystallized in Dante’s Divine Comedy, notably.      Finally, we intend to demonstrate, based on a close comparison of similar motifs present in Lovecraft’s novella, At the Mountains of Madness and in Hesiod’s poem, Theogony, a revelatory parallel between their respective aesthetics; aesthetics that spring from historically and essentially distinct paradigms of reality, but which are not opposed or contradictory.

Keyphrases: Lovecraft, Cosmogony, Paradigm of reality, History, Hesiod, Lovecraft
Variétés de drapeaux et opérateurs différentiels

Let G be a semisimple algebraic group on a field of characteristic 0. This thesis discusses a vanishing theorem for the higher cohomology of the sheaf D of differential operators on a flag variety of G. We show that if P is a parabolic subgroup of G, then H^i(G/P,D)=0 for all i>0.  In fact, we give three independent proofs of this theorem. The first proof, due to Hesselink, only works if the parabolic subgroup P is a Borel subgroup. It uses a spectral sequence argument as well as the Borel-Weil-Bott theorem. The second proof, due to Kempf, only works if the unipotent radical of P acts trivially on its Lie algebra. It only uses the Borel-Weil-Bott theorem. Finally, the third proof, due to Elkik, is valid for any parabolic subgroup. However, it uses the Grauert-Riemenschneider theorem.   We also present a detailled construction of the sheaf of differential operators on a variety.

Keyphrases: Sheaf of differential operators, Flag variety, Cotangent bundle, Algebra of differential operators, Weyl algebra, Algebraic group, Sheaf cohomology, Representation theory
Caractérisation du risque associé au virus de l'hépatite E chez le porc

In this study, a strain of porcine hepatitis E virus (HEV) isolated from the bile of a naturally-infected Canadian pig was used to inoculate two groups of piglets. In the early-phase experiment (E), 4 one month-old piglets, specific pathogen free (SPF), were monitored for 14 days. In the late-phase experiment (L) 9 piglets were monitored up to slaughter (120 days post-inoculation (pi)). Controls piglets (E=2 and L=3) were inoculated with free HEV bile. The presence of HEV was monitored routinely in their blood and feces. At necropsy, viral occurence was evaluated in organs at 7, 14 and 120 days pi. Interestingly, HEV was found to persist in the serum of some animals up to 84-105 days pi, despite the presence of IgG HEV antibodies in their blood. Fecal shedding was detected until 105 days pi for a portion of pigs. In organs, HEV RNA was detected in low amount of gallbladders at killing time, while it was detected in a large number of organs at 7 and 14 days pi. To assess the distribution of HEV in commercial finishing pig in Quebec, a sampling was realised in pigs from three slaughterhouses from Quebec. Approximately a hundred samples of feces, blood, bile and liver were collected in each slaughterhouse, on pigs intended for human consumption. A sample of each type was collected on each of the chosen pigs. Detection of HEV RNA was carried out using a nested RT-PCR on each sample and a human ELISA test was adapted for the detection of swine antibodies against HEV in swine serum samples. For pigs at slaughter, 12,9 % of the bile samples were positive to HEV RNA and a seroprevalence of IgG of 26,0 % was detected in swine. A phylogenetic analysis demonstrated that all strains of the study were in the genotype 3. All results demonstrate that porcine industry workers are potentially exposed to swine HEV by feces, blood and organs.

Keyphrases: Hepatitis E virus (HEV), Experimental infection, Swine, Seroprevalence, Phylogenetic analysis
Historical Consciousness and the Construction of Inter-Group Relations: The Case of Francophone and Anglophone History School Teachers in Quebec

This three-article thesis looks at the effects of historical consciousness on the negotiation of ethnicity and the structuring of group boundaries among national history teachers in Quebec. The province’s ambiguous ethnic dominance between Francophones and Anglophones sets the stage for revealing how teachers from Quebec’s parallel history classrooms historicize meanings of the past for ethno-cultural awareness and agency. Depending on how inter-group realities are constructed, these educators can either promote inter-group comprehension or preserve rigid co-existence.   The first article theorizes how social actors’ differing capacities to historicize the past, or to generate moral life patterns for temporal orientation, underlie their negotiations of ethnicity and agency toward the “significant Other.” By developing a repertory of parallel and equal tendencies of historical consciousness for grasping fluctuations in ethnic boundary maintenance, the article moreover argues how social actors’ willingness to recognize human moral and historical agency is central to group boundary porosity.   The second article discusses the findings of an exploratory study conducted on inter-group attitudes and mutual in-class treatments between Francophone and Anglophone educators in Montreal national history classrooms. Whereas most Francophone respondents are indifferent to Anglo-Québécois social realities and historical experiences, all Anglophone ones know and transmit those of the Franco-Québécois to their students. Mirroring each group’s sociological status, this divergence implies a dissimilarity in how past inter-group relations are historicized. Possible non-recognition of Anglo-Québécois moral and historical agency moreover explains the prevalent indifference among Francophone respondents.  The last article touches upon an in-depth study conducted on Francophone national history teachers’ historical consciousness of the Anglo-Québécois. By testing my aforementioned repertory, the study analyzed how respondents historicize temporal change when negotiating ethnicity and structuring group boundaries. While their views on “history” and their historicizing of different thematic contexts overwhelmingly lead respondents to reinforce ethno-cultural differences and to not recognize human moral and historical agency, half of them nonetheless demonstrate openness to learning about and transmitting Anglo-Québécois social realities and historical experiences. Despite such willingness, reliance on pre-established historical visions for constructing inter-group realities nevertheless highlights the exclusion of the latter when respondents set out to develop a national identity among students.

Keyphrases: Mémoire collective, Collective memory, Historical thinking, Ethnicity, Group boundaries, Dominance ethnique ambiguë, Ambiguous ethnic dominance, Parallel societies, History curriculum, National identity, Socialization, Education
Les groupes et l’Assemblée universitaire de l’Université de Montréal : rôles, conflits et fonctionnement

The aim of this study is to evaluate the role that groups play in the academic governance of Canadian universities, through the university Senate, during a period of financial retrenchment. Using a theoritical framework taken from Belanger & Lemieux (2002), Hardy (1996) and Jones (2001, 2004), the analysis focuses on the 2008 Winter semester sessions of the University Assembly of Université de Montréal. The results show that unions and associations did not show inter- and intra-group cohesion strong enough to counter the administration’s cohesiveness and ability to make alliances. The Assembly itself has seen its share of formal responsibilites wither and was, during the observation, little more than a soapbox for groups who wanted to place an item on the institutional agenda. The study highlights the importance of further study of inter-groups relationships in higher education, in parallel with the wider scientific trend of revision of management practices in universities.

Keyphrases: Université, Association, Gestion, Governance, University, Senate, Assembly, Groups, Administration, Union, Association, Collegiality, Management
La question de la traduction dans les pensées herméneutiques de Gadamer et de Ricœur

The hermeneutic thoughts of Gadamer and Ricœur both recognize a great importance, albeit somewhat discretely, to the issue of translation.  They view it as a philosophical model of value, but treat it from rather different perspectives.  Our study will present these two views of translation, insisting on both their similarities and differences.  We will see that if for Gadamer, translation is used mostly to emphasise the universality of the linguistic element, Ricœur is mostly interested in its ethical implications, which remain only implicit in Gadamer’s thought.

Keyphrases: Philosophy, Hermeneutics, Interpretation, Comprehension, Translation
La représentation de la masculinité dans les vidéoclips de musique
populaire : le code visuel et l’expression de la vulnérabilité masculine

The following study pursues an analysis of the various images of masculinity represented in popular culture, or more specifically music videos. It consists more precisely of a textual analysis of music videos according to the semiological approach. It is understood that such representations undergo a process of sensory attribution, serving to build the image of masculinity in society. Qualitatively, the method of analysis will first treat, and later explore, the main forms related to masculinity from a body of 29 music videos broadcast by the Québec entertainment station Musique Plus. The observation of visual codes is imperative to this undertaking as the codes provide the means by which various expressions of the masculine type might proliferate. Beginning with the premise that certain attributes, namely force and invulnerability, are typically masculine according to certain representations, we can further the analysis by comparing it to three main scenarios (the homme-enfant, the introspectif and the meneur) resulting from the video evidence under study. In the final analysis, I shall demonstrate how the findings rest within our current social frame where notions of masculine and feminine image tend to submit less and less to traditional models and are redefined in a new matrix.

Keyphrases: Representation, Masculinity, Vulnerability, Gender, Popular music, Music video, Visual code