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Sans résumé 相似文献
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Julie Dufour Aurélien Pommier Georges Alves Hugues De Boussac Corinne Lours-Calet David H. Volle Jean-Marc A. Lobaccaro Silvère Baron 《PloS one》2013,8(3)
Recent studies underline the implication of Liver X Receptors (LXRs) in several prostate diseases such as benign prostatic hyperplasia (BPH) and prostate cancer. In order to understand the molecular mechanisms involved, we derived epithelial cells from dorsal prostate (MPECs) of wild type (WT) or Lxrαβ−/− mice. In the WT MPECs, our results show that LXR activation reduces proliferation and correlates with the modification of the AKT-survival pathway. Moreover, LXRs regulate lipid homeostasis with the regulation of Abca1, Abcg1 and Idol, and, in a lesser extent, Srebp1, Fas and Acc. Conversely cells derived from Lxrαβ−/− mice show a higher basal phosphorylation and consequently activation of the survival/proliferation transduction pathways AKT and MAPK. Altogether, our data point out that the cell model we developed allows deciphering the molecular mechanisms inducing the cell cycle arrest. Besides, we show that activated LXRs regulate AKT and MAPK transduction pathways and demonstrate that LXRs could be good pharmacological targets in prostate disease such as cancer. 相似文献
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Daniele Novarina Georges E. Janssens Koen Bokern Tim Schut Noor C. van Oerle Hinke G. Kazemier Liesbeth M. Veenhoff Michael Chang 《Aging cell》2020,19(2)
To ensure proper transmission of genetic information, cells need to preserve and faithfully replicate their genome, and failure to do so leads to genome instability, a hallmark of both cancer and aging. Defects in genes involved in guarding genome stability cause several human progeroid syndromes, and an age‐dependent accumulation of mutations has been observed in different organisms, from yeast to mammals. However, it is unclear whether the spontaneous mutation rate changes during aging and whether specific pathways are important for genome maintenance in old cells. We developed a high‐throughput replica‐pinning approach to screen for genes important to suppress the accumulation of spontaneous mutations during yeast replicative aging. We found 13 known mutation suppression genes, and 31 genes that had no previous link to spontaneous mutagenesis, and all acted independently of age. Importantly, we identified PEX19, encoding an evolutionarily conserved peroxisome biogenesis factor, as an age‐specific mutation suppression gene. While wild‐type and pex19Δ young cells have similar spontaneous mutation rates, aged cells lacking PEX19 display an elevated mutation rate. This finding suggests that functional peroxisomes may be important to preserve genome integrity specifically in old cells. 相似文献
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Laure Gouinaud Andrew Martin Jean Hazebroucq Joëlle Texereau Georges Caillibotte 《Computer methods in biomechanics and biomedical engineering》2013,16(12):1358-1366
A numerical pressure loss model previously used for adult human airways has been modified to simulate the inhalation pressure distribution in a healthy 9-month-old infant lung morphology model. Pressure distributions are calculated for air as well as helium and xenon mixtures with oxygen to investigate the effects of gas density and viscosity variations for this age group. The results indicate that there are significant pressure losses in infant extrathoracic airways due to inertial effects leading to much higher pressures to drive nominal flows in the infant airway model than for an adult airway model. For example, the pressure drop through the nasopharynx model of the infant is much greater than that for the nasopharynx model of the adult; that is, for the adult-versus-child the pressure differences are 0.08 cm H2O versus 0.4 cm H2O, 0.16 cm H2O versus 1.9 cm H2O and 0.4 cm H2O versus 7.7 cm H2O, breathing helium–oxygen (78/22%), nitrogen–oxygen (78/22%) and xenon–oxygen (60/40%), respectively. Within the healthy lung, viscous losses are of the same order for the three gas mixtures, so the differences in pressure distribution are relatively small. 相似文献
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Brigitte Allart Danielle Guillerm Georges Guillerm 《Nucleosides, nucleotides & nucleic acids》2013,32(4-5):861-862
Abstract AdoHcy/MTA nucleosidase has been under scrutiny in a series of studies to explore its catalytic mechanism. 相似文献
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Specimens were studied of 65 samples of the genus Aphidura (Aphididae, Aphidinae, Macrosiphini) from the collection of the Muséum national d’Histoire naturelle (Paris). The possible synonymies of three pairs of species are discussed. New aphid host plant relationships are reported for Aphidura bozhkoae, Aphidura delmasi, Aphidura ornata, Aphidura pannonica and Aphidura picta; this last species is recorded for first time from Afghanistan. The record of Aphidura pujoli from Pakistan is refuted. The fundatrices, oviparous females and males of Aphidura delmasi are described. Six new species are established: Aphidura gallica
sp. n. and Aphidura amphorosiphon
sp. n. from specimens caught on species of Silene (Caryophyllaceae) from France and Iran, respectively, Aphidura pakistanensis
sp. n., Aphidura graeca
sp. n. and Aphidura urmiensis
sp. n. from specimens caught on species of Dianthus, Gypsophila and Spergula (Caryophyllaceae) from Pakistan, Greece and Iran, respectively, and Aphidura iranensis
sp. n. from specimens caught on Prunus sp. from Iran. Modifications are made to the keys by Blackman and Eastop to aphids living on Dianthus, Gypsophyla, Silene, Spergula and Prinsepia and Prunus (Rosaceae). An identification key to apterous viviparous females of species of Aphidura is also provided. 相似文献