11 research outputs found
Université d'entreprise : entreprise ou université ?
Atelier 18 : TIC et moyens d'apprentissage informelsLes université d'entreprise prennent de plus en plus de place dans les outils de développement des compétences dans l'entreprise. Nous pensons que cette émergence justifie une recherche pour mieux comprendre ces universités d'entreprise. Nous pensons que cette analyse doit se faire à travers les interactions entre entreprise et université d'entreprise. Nous voulons plus particulièrement analyser l'intégration des nouvelles technologies dans les apprentissages proposés. Cette communication a pour objectif de poser le cadre méthodologique dans lequel nous allons agir et poser quelques hypothèses que nous testerons dans une étude future
Au gré de la brise : mazurka pour piano / par Charles Bariller
Titre uniforme : Bariller, Charles (18..-1917). Compositeur. [Au gré de la brise. Piano
Le réveillon : polka de la pièce de M. M. H. Meilhac et L. Halévy pour piano / par Jules Bariller ; [ill. par] Jannin & Denis
Titre uniforme : Bariller, Jules (1825?-1884). Compositeur. [Le réveillon. Piano
Les Françaises : suite de valses pour le piano / par Charles Bariller ; [ill. par] L. Denis
Titre uniforme : Bariller, Charles (18..-1917). Compositeur. [Les Françaises
Le réveillon : polka de la pièce de M. M. H. Meilhac et L. Halévy pour piano / par Jules Bariller ; [ill. par] Jannin & Denis
Titre uniforme : Bariller, Jules (1825?-1884). Compositeur. [Le réveillon. Piano
Highly asymmetric intergeneric nuclear hybrids between Nicotiana and Petunia: evidence for recombinogenic and translocation events in somatic hybrid plants after "gamma"-fusion
Extremely asymmetric nuclear hybrids have been obtained via protoplast fusion in an intergeneric combination. Irradiated (cobalt60,100 krad) kanamycinresistant Petunia hybrida mesophyll protoplasts were chemically fused with wild-type mesophyll protoplasts of Nicotiana plumbaginifolia. Eighty-six hybrid colonies were selected on kanamycin-containing medium, and twenty-four of these could be induced to regenerate numerous shoots. Cytological analysis of the regenerants showed the presence of a few chromosome fragments in some lines, and even a metacentric chromosome in yet another line. Besides additional chromosome fragments some lines only possessed typical Nicotiana chromosomes, and this at the diploid (2n = 2X = 20) as well as the tetraploid (2n = 2X = 40) level. Biochemical analysis showed that all regenerants had neomycin phosphotransferase activity (NPTII), which suggests that intergenomic recombination and or translocation events took place at least in those lines where no additional chromosome fragments could be detected. The presence of the NPTII gene was shown by Southern hybridization. All regenerants tested were fertile, and the segregation ratios for the kanamycin gene (for self and backcross pollinations to the recipient partner) for some of the regenerants correspond with Mendelian rules for a monogenic dominant marker. Most of the regenerants showed abnormal segregation ratios; in this case, no correlation could be made between segregation ratio and chromosome composition. Our results demonstrate the existence of intergenomic recombination and translocations evens in nuclear somatic hybrid plants obtained via "gamma"-fusion. © 1991 Springer-Verlag.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
A3.20 The calcium sensor stromal interaction molecule 1 (STIM1) controls regulatory B cell functions and its activity is impaired in Systemic Lupus Erythematosus patients.
International audienceBACKGROUND AND OBJECTIVES: The immunosuppressive function of regulatory B cells (Breg) is defective in B cells from systemic lupus erythematosus (SLE) patients. Since the Ca(2+) pathway is also altered in SLE B cells, the aim of the study was to explore the contribution of the Ca(2+) channel Orai1 and its regulator, the stromal interaction molecule 1 (STIM1), on regulatory B cell functions. MATERIALS AND METHODS: Thirty SLE patients and healthy controls (HC) were included in the study. Orai1 and STIM1 expressions were explored in CD40/CpG activated B cells, and in the stimulated (anti-CD3, anti-CD28 plus CpG-ODN 2006) T- and B- cell autologous co-culture Breg model. Transfection were used using either siRNAs to down-modulate STIM1 in SLE B cells, or either the cDNA STIM1 vector in HC B cells. RESULTS: After 3 days, in CD40/CpG activated HC B cells, and in HC B cells stimulated during co-cultures, acquisition of the Breg phenotype (IgD/CD38/CD24/CD5(high)) was associated with an over-expression of the Ca(2+) regulator STIM1 (x10.8 and x7.1 fold increase respectively). At day 4 and even more at day 5, STIM1 expression declined in co-cultures and this down-regulation was accompanied with IL-10 and TGF-beta up-regulation in B cells, FoxP3(+) regulatory T cell expansion, and a reduction of T cell proliferation. Expression of the Ca(2+) channel Orai1 was stable. In SLE B cells, STIM1 expression was overexpressed at basal level when compared to HC B cells (x4.3 fold) and remains elevated in B cells during all the time of the autologous co-culture (x8.8 fold). Then we hypothesised that maintaining high levels of STIM1 was critic in the regulatory capacity of SLE B cells. Accordingly, we demonstrated that STIM1 downregulation in SLE B cells, using a specific siRNA, was effective to restore IL-10, but not TGF-beta, expression, FoxP3(+) regulatory SLE T cell expansion, and SLE T cell inhibition. In HC B cells, forcing STIM1 expression, with a STIM1 vector, was effective to reproduce the abnormalities observed in SLE B cells. No association was observed between STIM1 expression at basal level and organ involvement, disease activity (SLEDAI), or serological parameters thus suggesting that STIM1 over-expression and Ca(2+) dysregulations are primary events in SLE. CONCLUSIONS: Altogether, this study reveals that acquisition of the Breg phenotype and Breg functions are tightly regulated by STIM1. Furthermore, this observation could provide innovative B-cell based treatment to convert B cells into immunosuppressive cells with applications in human autoimmunity and in SLE. KEY WORDS: lupus, regulatory B cells, calcium, STIM1, IL-10
B-Lymphocyte Signalling Abnormalities and Lupus Immunopathology
International audienceLupus is a complex autoimmune rheumatic disease of unknown aetiology. The disease is associated with diverse features of immunological abnormality in which B-lymphocytes play a central role. However, the cause of atypical B-lymphocyte responses remains unclear. In this article, we provide a synopsis of current knowledge on intracellular signalling abnormalities in B-lymphocytes in lupus and their potential effects on the response of these cells in mouse models and in patients. There are numerous reported defects in the regulation of intracellular signalling proteins and pathways in B-lymphocytes in lupus that, potentially, affect critical biological responses. Most of the evidence for these defects comes from studies of disease models and genetically engineered mice. However, there is also increasing evidence from studying B-lymphocytes from patients and from genome-wide linkage analyses for parallel defects to those observed in mice. These studies provide molecular and genetic explanations for the key immunological abnormalities associated with lupus. Most of the new information appears to relate to defects in intracellular signalling that impact B-lymphocyte tolerance, cytokine production and responses to infections. Some of these abnormalities will be discussed within the context of disease pathogenesis