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La pratique musicale traditionnelle Dans les populations touarègues pratiquant encore le nomadisme saisonnier, ce sont les femmes qui ont le monopole de la musique instrumentale et, parmi elles, celles des classes sociales les plus élevées dans la hiérarchie qui peuvent jouer de la vièle monocorde imẓad * (ou anẓad) alors que les femmes forgeronnes ou ex-captives se limitent au jeu du tambour sur mortier tendey/tindé*. Quand elles chantent en soliste, les femmes le font toujours accompagnées ...

Adenosine triphosphate (ATP)-binding cassette (ABC) transporters are drug efflux pumps responsible for the multidrug resistance phenotype causing hepatocellular carcinoma (HCC) treatment failure. Here we studied the expression of 15 ABC transporters relevant for multidrug resistance in 19 paired HCC patient samples (16 untreated, 3 treated by chemotherapeutics). Twelve ABC transporters showed up-regulation in HCC compared with adjacent healthy liver. These include ABCA2, ABCB1, ABCB6, ABCC1, ABCC2, ABCC3, ABCC4, ABCC5, ABCC10, ABCC11, ABCC12, and ABCE1. The expression profile and function of some of these transporters have not been associated with HCC thus far. Because cellular microRNAs (miRNAs) are involved in posttranscriptional gene silencing, we hypothesized that regulation of ABC expression in HCC might be mediated by miRNAs. To study this, miRNAs were profiled and dysregulation of 90 miRNAs was shown in HCC compared with healthy liver, including up-regulation of 11 and down-regulation of 79. miRNA target sites in ABC genes were bioinformatically predicted and experimentally verified in vitro using luciferase reporter assays. In total, 13 cellular miRNAs were confirmed that target ABCA1, ABCC1, ABCC5, ABCC10, and ABCE1 genes and mediate changes in gene expression. Correlation analysis between ABC and miRNA expression in individual patients revealed an inverse relationship, providing an indication for miRNA regulation of ABC genes in HCC. Conclusion: Up-regulation of ABC transporters in HCC occurs prior to chemotherapeutic treatment and is associated with miRNA down-regulation. Up-regulation of five ABC genes appears to be mediated by 13 cellular miRNAs in HCC patient samples. miRNA-based gene therapy may be a novel and promising way to affect the ABC profile and overcome clinical multidrug resistance. (Hepatology 2012)

La flûte est présente dans tout le Magreb, aussi bien dans les populations arabopbones que herbèrophones. Elle est confectionnée à partir d’un tuyau de roseau (de bambou, de métal, voire de matière plastique) ouvert aux deux extrémités et percé d’un certain nombre de trous. Parfois, elle est gravée de motifs décoratifs peints en rouge (comme par exemple en Kabylie) ou pyrogravés. L’embouchure terminale est simple, non aménagée, sinon bisotée. Le musicien tient sa flûte obliquement, pour facil...

Hepatocellular carcinoma (HCC) is a primary cancer of the liver, and HCC patients have an average survival of only 5% at 5-year post-diagnosis. This low survival has several identified causes, among which multidrug resistance i.e. resistance to chemotherapeutic treatment. These issues need be addressed in order to improve HCC management in the future. In this thesis we questioned the role of ABC transporters in HCC, and aimed at developing RNAi-based strategies to compensate their dysregulation. Two strategies were developed to modulate ABC transporter gene expression. The first one exploited endogenous regulation of ABC transporter genes by cellular miRNAs while the second strategy made use of shRNAs and artificial miRNAs for ABCC1 and ABCC2 knock-down. In conclusion, this research contributed to the development of two RNAi-based strategies to compensate ABC transporter gene dysregulation in HCC. At this moment the RNAi field faces toxicity-related and unanticipated off-targeting challenges that need to be overcome in order to take the technology forward, but once these limitations are fully apprehended, it will undoubtedly lead to significant advances for HCC diagnostics and therapeutics.

International audience; Due to their important adaptive potentialities, tilapia have colonised a wide range of habitats which could be related to their various reproductive strategies. Some traits of the reproductive cycle present a great plasticity and can be modulated by many environmental and/or social factors. We investigated some of them under controlled conditions in three tilapia species, Oreochromis niloticus, O. aureus and the red tilapia (Red Florida strain). At a constant temperature, a clear influence of a seasonal photoperiod is demonstrated on the reproductive activity of O. aureu#. Under a typical tropical 12L:12D photoperiod, most reproductions occurred in the mid-afternoon (3 p.m.). Environmental complexity strongly stimulated the production; both reproductive activity and fry survival seemed to be stimulated by the presence of artificial shelters. The reproductive cycle of #O. niloticus# is characterised by the variability of its periodicity: vitellogenesis can be delayed or stimulated by the maternal behaviour as demonstrated by eggs/fry suppression or exchange experiments. In O. niloticus, O. aureus and the red tilapia, the reproductive activity of individually tagged male and female breeders has been investigated during long term periods (8-12 months) in tanks or race-ways. When seed were removed from incubating females at a 10 day interval, few males and females were involved in the overall fry production. Apparently, the other females only took part into spawning activity during the inter spawning period of the most active breeders. The individual characteristics of the clutches produced by these two types of females have been compared. The importance of social factors in the reproductive efficiency of tilapia species is discussed.