Développement de la stratégie de polycyclisations de Mannich en cascade mise au point de l'activation chimiosélective d'amide et étude de nucleophiles compatibles

Ce mémoire porte sur l'étude d'une nouvelle stratégie de synthèse qui pourra être ultérieurement utilisée pour la synthèse de différents composés naturels de type alcaloïdes. Cette méthode emploie les polyclisations de Mannich via la génération double d'iminiums en tandem.Ce mémoire décrit le développement et l'optimisation de différentes conditions d'activation d'amide ainsi que la synthèse de différents modèles linéaires pour faire l'étude de la biscyclisation en tandem. Le présent ouvrage se divise en sections; tout d'abord, en guise d'introduction, une brève revue de la littérature sur les précédents, ainsi que les différentes structures accessibles, ce qui cernera la problématique et la pertinence du projet. Ensuite le développement et l'optimisation de différentes conditions d'activation d'un amide seront rapportées. En troisième lieu, nous verrons les séquences menant aux différents modèles pour l'étude de la cyclisation en cascade. Finalement, diverses voies de complétion du projet seront également proposées

Addition of tethered nonaromatic carbon nucleophiles to chemoselectively activated amides

Abstract: In an effort to develop new ways of synthesizing polycyclic alkaloids, we successfully added silyl enol ethers, allylsilanes, and enamines to iminium ions generated from amides. Because of their higher oxidation state, such iminiums show a yet unexploited advantage of potential double cyclizations over standard Mannich monocyclizations. We report herein the first example of tethered nonaromatic carbon nucleophiles adding to activated amides for the generation of enaminals of various ring sizes, with endo- or exo-cyclic nitrogen

Identification of Novel Genetic Markers Associated with Clinical Phenotypes of Systemic Sclerosis through a Genome-Wide Association Strategy

Contains fulltext : 97006.pdf (publisher's version ) (Open Access)The aim of this study was to determine, through a genome-wide association study (GWAS), the genetic components contributing to different clinical sub-phenotypes of systemic sclerosis (SSc). We considered limited (lcSSc) and diffuse (dcSSc) cutaneous involvement, and the relationships with presence of the SSc-specific auto-antibodies, anti-centromere (ACA), and anti-topoisomerase I (ATA). Four GWAS cohorts, comprising 2,296 SSc patients and 5,171 healthy controls, were meta-analyzed looking for associations in the selected subgroups. Eighteen polymorphisms were further tested in nine independent cohorts comprising an additional 3,175 SSc patients and 4,971 controls. Conditional analysis for associated SNPs in the HLA region was performed to explore their independent association in antibody subgroups. Overall analysis showed that non-HLA polymorphism rs11642873 in IRF8 gene to be associated at GWAS level with lcSSc (P = 2.32x10(-12), OR = 0.75). Also, rs12540874 in GRB10 gene (P = 1.27 x 10(-6), OR = 1.15) and rs11047102 in SOX5 gene (P = 1.39x10(-7), OR = 1.36) showed a suggestive association with lcSSc and ACA subgroups respectively. In the HLA region, we observed highly associated allelic combinations in the HLA-DQB1 locus with ACA (P = 1.79x10(-61), OR = 2.48), in the HLA-DPA1/B1 loci with ATA (P = 4.57x10(-76), OR = 8.84), and in NOTCH4 with ACA P = 8.84x10(-21), OR = 0.55) and ATA (P = 1.14x10(-8), OR = 0.54). We have identified three new non-HLA genes (IRF8, GRB10, and SOX5) associated with SSc clinical and auto-antibody subgroups. Within the HLA region, HLA-DQB1, HLA-DPA1/B1, and NOTCH4 associations with SSc are likely confined to specific auto-antibodies. These data emphasize the differential genetic components of subphenotypes of SSc

Développement de la stratégie de polycyclisations de Mannich en cascade mise au point de l'activation chimiosélective d'amide et étude de nucleophiles compatibles

Ce mémoire porte sur l'étude d'une nouvelle stratégie de synthèse qui pourra être ultérieurement utilisée pour la synthèse de différents composés naturels de type alcaloïdes. Cette méthode emploie les polyclisations de Mannich via la génération double d'iminiums en tandem.Ce mémoire décrit le développement et l'optimisation de différentes conditions d'activation d'amide ainsi que la synthèse de différents modèles linéaires pour faire l'étude de la biscyclisation en tandem. Le présent ouvrage se divise en sections; tout d'abord, en guise d'introduction, une brève revue de la littérature sur les précédents, ainsi que les différentes structures accessibles, ce qui cernera la problématique et la pertinence du projet. Ensuite le développement et l'optimisation de différentes conditions d'activation d'un amide seront rapportées. En troisième lieu, nous verrons les séquences menant aux différents modèles pour l'étude de la cyclisation en cascade. Finalement, diverses voies de complétion du projet seront également proposées

Transcriptional profiling of human uveal melanoma from cell lines to intraocular tumors to metastasis

Uveal melanoma is the most common primary intraocular tumor in adults and exclusively disseminates haematogenously in order to form metastases. The aim of this study was to measure the transcriptional profiles of human uveal melanoma cells isolated from a primary intraocular tumor, circulating malignant cells (CMCs), and metastases in order to elucidate the changes in gene expression associated with this progression. Human EST microarrays and universal reference RNA were used to measure the differences between tissue samples isolated from an immunosuppressed xenograft rabbit model of uveal melanoma. Cells were isolated from a single rabbit at the time of sacrifice from an intraocular tumor, peripheral blood, and metastasis. RNA was extracted from each sample and subjected to transcriptional profiling analysis. Results were compared to the transcriptional profiles previously obtained from the original cell line used for intraocular injections. Changes were verified using real-time PCR analysis. A total of 314 significant changes in gene expression were seen from the intraocular tumor to metastasis, as determined by transcript abundance. Principle Components Analysis was used to cluster these changes into four distinct groups. An additional 61 statistically significant changes were observed between the recultured and CMCs, with the latter believed to represent an intermediate step in the progression from intraocular tumor to metastasis. In conclusion, we have produced a detailed analysis of the transcriptional changes that take place as human uveal melanoma cells evolve from a primary tumor to metastasis in a xenograft animal model, including the decrease in expression of specific melanoma markersNRC publication: Ye

Expression profiling of formalin-fixed paraffin embedded primary human uveal melanomas using DASL matrices

Fresh biopsied ocular tumor tissues are difficult to obtain for the purpose of performing microarray experiments on extracted nucleic acids. Present technology allows for extraction of total RNA from formalin-fixed paraffin embedded (FFPE) tissue analyzed by the cDNA mediated Annealing Sectioning and Ligation (DASL) method. We aimed to correlate gene transcript differences between two uveal melanoma (UM) clinical-histopathological parameters (metastasis, cell type).A total of 43 FFPE UM were used. the expression of RPL13a, a ribosomal protein gene, for each sample was used to evaluate the quality of RNA extracted from FFPE tissue. Gene expression values generated from the array were analyzed using the GeneSpring GX software (Agilent). Immunohistochemistry was used in order to validate transcriptional findings at the protein level.A total of 106 genes were identified with (P < 0.05, Welch ANOVA test) a difference in transcript abundance for the metastasis clinical parameter. Furthermore, we identified 64 genes with a statistically significant (P < 0.05) difference in transcript abundance between the spindle and epithelioid cell types. Each individual sample for both groups (metastasis, cell type) exhibited distinct transcriptional profiles that were separated on a PCA. Positive nuclear immunostaining for LIG4-metastasis, ErbB3-cell type was found to be associated with better patient prognosis and outcome.To the best of our knowledge, this is the first time that a successful retrospective analysis has been done with UM FFPE RNA. This data may lead to future customized therapeutic targets, which may improve the now unchanged mortality rate of this particular malignancy.Cedars Cancer InstituteHellen Keller FoundationMcGill Univ, Ctr Hlth, Henry C Witelson Ophthalm Pathol Lab, Montreal, PQ H3A 2B4, CanadaMcGill Univ, Ctr Hlth, Henry C Witelson Ophthalm Pathol Registry, Montreal, PQ H3A 2B4, CanadaNatl Res Council Canada, Biotechnol Res Inst, Montreal, PQ H4P 2R2, CanadaNCI, NIH, Bethesda, MD 20892 USAUniversidade Federal de São Paulo, UNIFESP EPM, Dept Ophthalmol, São Paulo, BrazilUniv Valladolid, Dept Ophthalmol, Ocular Pathol Lab, Valladolid, SpainUniversidade Federal de São Paulo, UNIFESP EPM, Dept Ophthalmol, São Paulo, BrazilWeb of Scienc

The influence of childhood obesity on spatio-temporal gait parameters

The musculoskeletal and neurosensorial development of children can be affected by excess body weight. Studies have examined how childhood obesity affects gait, but much about the influence of this factor remains to be determined. The aim of our study is to analyse, in a large sample of children, the influence of obesity on the spatiotemporal parameters of the gait cycle, in the most natural way possible, with the subjects walking overground at a self-selected speed. For this study, the sample was composed of 238 healthy school children, composed of 114 (47.9%) girls and 124 (52.1%) boys, aged 7-11 years. For each one, the body mass index was calculated, according to which the subjects were classified by percentiles as low weight, normal weight, overweight or obese. Anthropometric variables were measured and the spatiotemporal parameters of gait were assessed by the OptoGait® portable photocell system. The spatial variables did not reveal significant differences between the children with normal weight and those with obesity. However, the differences for stance phase, load response and pre-swing phase (p = 0.0001, p = 0.016 and p = 0.0001, respectively) were clearly significant. Childhood obesity exerts a significant influence on gait by increasing the duration of load response and that of the pre-swing towards the oscillation phase and therefore the total duration of the support phase. This outcome requires greater energy expenditure to stabilise the gait of children with obesity, and could have biomechanical repercussions