Étude du rôle de la lipase hormono-sensible dans le métabolisme du cholestérol dans le testicule de cobaye et de vison

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

Régulation de la lipoprotéine lipase macrophagique dans l'hypercholestérolémie familiale et le diabète de type 2

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

Étude comparative entre la quantité de Candida spp. présente sur le palais et sur la pièce prothétique chez les patients porteurs d'une prothèse complète au maxillaire supérieur

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

Étude structure-fonction des transporteurs ABC de Candida albicans impliqués dans la résistance aux agents antifongiques

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

Relation entre la commutation phénotypique de Candida albicans et la stomatite prothétique

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

Interaction between Candida albicans and Pseudomonas aeruginosa

Fungal pathogen Candida albicans causes serious nosocomial infections in patients, in part, due to formation of drug-resistant biofilms. Protein kinases (PK) and transcription factors (TF) mediate signal transduction and transcription of proteins involved in biofilm development. To discover biofilm-related PKs, a collection of 63 C. albicans PK mutants was screened twice independently with microtiter plate-based biofilm assay (XTT). Thirty-eight (60%) mutants showed different degrees of biofilm impairment with the poor biofilm formers additionally possessing filamentation defects. Most of these genes were already known to encode proteins associated with Candida morphology and biofilms but VPS15, PKH3, PGA43, IME2 and CEX1, were firstly associated with both processes in this study. Previous studies of Holcombe et al. (2010) had shown that bacterial pathogen, Pseudomonas aeruginosa can impair C. albicans filamentation and biofilm development. To investigate their interaction, the good biofilm former PK mutants of C. albicans were assessed for their response to P. aeruginosa supernatants derived from two strains, wildtype PAO1 and homoserine lactone (HSL)-free mutant ΔQS, without finding any nonresponsive mutants. This suggested that none of the PKs in this study was implicated in Candida-Pseudomonas signaling. To screen promoter sequences for overrepresented TFs across C. albicans gene sets significantly up/downregulated in presence of bacterial supernatants from Holcombe et al. (2010) study, TFbsST database was created online. The TFbsST database integrates experimentally verified TFs of Candida to analyse promoter sequences for TF binding sites. In silico studies predicted that Efg1p was overrepresented in C. albicans and C. parapsilosis RBT family genes.

Étude du rôle de la lipase hormono-sensible dans le métabolisme du cholestérol dans le testicule de cobaye et de vison

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

Régulation de la lipoprotéine lipase macrophagique dans l'hypercholestérolémie familiale et le diabète de type 2

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

Étude comparative entre la quantité de Candida spp. présente sur le palais et sur la pièce prothétique chez les patients porteurs d'une prothèse complète au maxillaire supérieur

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

Étude structure-fonction des transporteurs ABC de Candida albicans impliqués dans la résistance aux agents antifongiques

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

Relation entre la commutation phénotypique de Candida albicans et la stomatite prothétique

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

Saccharomycotin transcriptomics by next-generation sequencing

The non-standard decoding of the CUG codon in Candida cylindracea raises a number of questions about the evolutionary process of this organism and other species Candida clade for which the codon is ambiguous. In order to find some answers we studied the transcriptome of C. cylindracea, comparing its behavior with that of Saccharomyces cerevisiae (standard decoder) and Candida albicans (ambiguous decoder). The transcriptome characterization was performed using RNA-seq. This approach has several advantages over microarrays and its application is booming. TopHat and Cufflinks were the software used to build the protocol that allowed for gene quantification. About 95% of the reads were mapped on the genome. 3693 genes were analyzed, of which 1338 had a non-standard start codon (TTG/CTG) and the percentage of expressed genes was 99.4%. Most genes have intermediate levels of expression, some have little or no expression and a minority is highly expressed. The distribution profile of the CUG between the three species is different, but it can be significantly associated to gene expression levels: genes with fewer CUGs are the most highly expressed. However, CUG content is not related to the conservation level: more and less conserved genes have, on average, an equal number of CUGs. The most conserved genes are the most expressed. The lipase genes corroborate the results obtained for most genes of C. cylindracea since they are very rich in CUGs and nothing conserved. The reduced amount of CUG codons that was observed in highly expressed genes may be due, possibly, to an insufficient number of tRNA genes to cope with more CUGs without compromising translational efficiency. From the enrichment analysis, it was confirmed that the most conserved genes are associated with basic functions such as translation, pathogenesis and metabolism. From this set, genes with more or less CUGs seem to have different functions. The key issues on the evolutionary phenomenon remain unclear. However, the results are consistent with previous observations and shows a variety of conclusions that in future analyzes should be taken into consideration, since it was the first time that such a study was conducted.