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The mTOR pathway is a conserved master regulator of translational activity that influences the fate of industrially relevant CHO cell cultures, yet its molecular mechanisms remain unclear. Interestingly, rapamycin specific inhibition of the mTOR pathway in CHO cells was found to down-regulate the small nucleolar RNA U19 (snoRNA U19) by 2-fold via translatome profiling. snoRNA U19 guides the two most conserved pseudouridylation modifications on 28S ribosomal RNA (rRNA) that are important for the biogenesis and proper function of ribosomes. In order to further understand the role of snoRNA U19 as a potential player in the mTOR pathway, we measured 28S rRNA pseudouridylation upon rapamycin treatments and/or snoRNA U19 overexpression conditions, thereby characterizing the subsequent effects on ribosome efficiency and global translation by polysome profiling. We showed that 28S rRNA pseudouridylation was increased by rapamycin treatment and/or overexpression of snoRNA U19, but only the latter condition improved ribosome efficiency toward higher global translation, thus implying that the mTOR pathway induces pseudouridylation at different sites along the 28S rRNA possibly with either positive or negative effects on the cellular phenotype. This discovery of snoRNA U19 as a new downstream effector of the mTOR pathway suggests that cell engineering of snoRNAs can be used to regulate translation and improve cellular growth in CHO cell cultures in the future., National University of Singapore, Singapore. Agency for Science, Technology and Research, Korea (South). Rural Development Administration. Next-Generation BioGreen 21 Program (SSAC PJ009520)

We report the first investigation of translational efficiency on a global scale, also known as translatome, of a Chinese hamster ovary (CHO) DG44 cell line producing monoclonal antibodies (mAb). The translatome data was generated via combined use of high resolution and streamlined polysome profiling technology and proprietary Nimblegen microarrays probing for more than 13K annotated CHO-specific genes. The distribution of ribosome loading during the exponential growth phase revealed the translational activity corresponding to the maximal growth rate, thus allowing us to identify stably and highly translated genes encoding heterogeneous nuclear ribonucleoproteins (Hnrnpc and Hnrnpa2b1), protein regulator of cytokinesis 1 (Prc1), glucose-6-phosphate dehydrogenase (G6pdh), UTP6 small subunit processome (Utp6) and RuvB-like protein 1 (Ruvbl1) as potential key players for cellular growth. Moreover, correlation analysis between transcriptome and translatome data sets showed that transcript level and translation efficiency were uncoupled for 95% of investigated genes, suggesting the implication of translational control mechanisms such as the mTOR pathway. Thus, the current translatome analysis platform offers new insights into gene expression in CHO cell cultures by bridging the gap between transcriptome and proteome data, which will enable researchers of the bioprocessing field to prioritize in high-potential candidate genes and to devise optimal strategies for cell engineering toward improving culture performance.

The mammalian target of rapamycin (mTOR) pathway plays essential roles in the regulation of translational activity in many eukaryotes. Thus, from a bioprocessing point of view, understanding its molecular mechanisms may provide potential avenues for improving cell culture performance. Toward this end, the mTOR pathway of CHO cells in batch cultures was subjected to rapamycin treatment (inhibition) or nutrient supplementation (induction) and translational activities of CHO cells producing a monoclonal antibody (mAb) were evaluated with polysome profiling technology. Expectedly, rapamycin induced a shift of mRNAs from polysomes towards monosomes, thus reducing maximum cellular growth rate by 30%, while feeding additional nutrients extended mTOR pathway activity during the stationary growth phase in control batch culture, thereby contributing to an increase in global translation activity by up to 2-fold, and up to 5-fold higher specific translation of the heavy and light chains of the recombinant mAb. These increases in translation activity correlated with a 5-day extension in cellular growth and a 4-fold higher final product titer observed upon nutrient feeding. This first study of the relationship between the mTOR pathway and translational activity in CHO cultures provides key insights into the role of translational control in supporting greater productivity, which will lead to further enhancement of CHO cultures.

For several years, studies performed to estimate in vitro biocompatibility of urinary catheters have been carried out using permanent cell lines. But for a rational design of the testing procedure, the cell culture model should relate to the material application. This work presents the results of a probe study designed to obtain an in vitro model of normal human urothelial cells (HUC) and to test the relevance of this system in cytocompatibility experiments of urinary catheters currently used.A comparison is made with continuous cell lines, the use of which is recommended by normalization bodies. We exposed monolayers of HUC (well characterized for their proliferation, qualitative evaluation, and quantitative measurement of cytokeratins) and two continuous human cell lines to liquid extracts (either pure or diluted in the culture medium) of nine available catheters, including positive (latex) and negative controls, for a 24 h incubation. Then colorimetric assays (Neutral Red and MTT) were performed. The extracts of two polyurethanes provoked a significant toxic effect on HUC only, suggesting differences in sensitivity between the models used. This effect could be due to the presence of a great amount of barium (used as a radioopacifier) in extracts, as highlighted by results of absorption emission spectroscopy. A culture model of HUC may be of relevance for the screening of materials intended for urological practice.

La montee du sel triasique a profondement influence la structure profonde du sous-sol de l'avant-pays pyreneen.L'halocinese deforme et redresse les terrains susjacents et en particulier les horizons dolomitiques poreux et fissures du Cretace superieur et du Paleocene.Ainsi, se trouvent creees :. des anomalies structurales de type diapir ou de faille injectee,. des anomalies du champ geothermique :. anomalies de conduction a Saint-Paul-les-Dax, Eugenie-les-Bains (Christine-Marie), Dax (GDX,) sans emergence naturelle.. anomalies de convection forcee aux emergences naturelles de Prechacq, Dax, Saubusse, Tercis.Cette double particularite structurale et thermique cree la structure thermale type du Pays landais.A Vemergence naturelle (source) ou provoquee (forage), l'eau thermale possede un caractere physico-chimique (temperature et facies chimique) variable et influence par :. l'origine et l'histoire de l'eau,. la nature et la geometrie du reservoir,. la condition d'emergence.

L'etude de l'interaction d'une eau chloro-sulfuree sodique avec l'acetylcholine confirme le role antagoniste des especes reduites du soufre vis-a-vis de la contraction provoquee par l'acetylcholine et souligne l'importance pharmacologique des thiols.La dilution et ioxygenation menagee peuvent conduire a des concentrations en certaines especes reduites superieures aux valeurs fournies par le calcul.Le mode d'action faisant intervenir une modulation des concentrations de nuleotides par effet red-ox semble envisageable dans le cas des eaux sulfurees.

For several years, studies performed to estimate in vitro biocompatibility of urinary catheters have been carried out using permanent cell lines. But for a rational design of the testing procedure, the cell culture model should relate to the material application. This work presents the results of a probe study designed to obtain an in vitro model of normal human urothelial cells (HUC) and to test the relevance of this system in cytocompatibility experiments of urinary catheters currently used.A comparison is made with continuous cell lines, the use of which is recommended by normalization bodies. We exposed monolayers of HUC (well characterized for their proliferation, qualitative evaluation, and quantitative measurement of cytokeratins) and two continuous human cell lines to liquid extracts (either pure or diluted in the culture medium) of nine available catheters, including positive (latex) and negative controls, for a 24 h incubation. Then colorimetric assays (Neutral Red and MTT) were performed. The extracts of two polyurethanes provoked a significant toxic effect on HUC only, suggesting differences in sensitivity between the models used. This effect could be due to the presence of a great amount of barium (used as a radioopacifier) in extracts, as highlighted by results of absorption emission spectroscopy. A culture model of HUC may be of relevance for the screening of materials intended for urological practice.

A man, aged 41 years, suffering from anaemia and abdominal pains was admitted to the Department of Medicine. Over the previous 2 years he had had several periods in hospital for these symptoms. There was, apparently, no occupational or accidental exposure to toxic substances and a correct diagnosis of the condition had not been possible. The computer-aided program AIDEDIAG II was therefore used to attempt a diagnosis. This approach indicated possible saturnism which was confirmed by metabolic and lead analyses. The lead source was identified as the hand-made food-plates used by the patient for his meals.

In the rat, the activity of the thermal water of Capvern and of its ionic components on the modification of the flow rate and composition of hepatic bile has been investigated. Two groups of rats were selected:the first group received per os an overload of the thermal water during six weeks. At that time on empty stomach a great increase of biliary phospholipids was observed. An intraduodenal injection of the thermal water produced a significant and rapid increase of biliary flow rate and biliary cholesterol.the animals of the second group received through intraduodenal injections the thermal water or an anionic solution composed of calcium, of magnesium sulphate or of both salts at their concentration in the thermal water, respectively. We observed an increase in biliary flow rate and biliary calcium concentration in the rats receiving the solution of calcium sulphate only and an increase of choleresis in the rats receiving the thermal water only.These data suggest that the thermal water has a sp...

Salies de Bearn fabrique a partir de l'eau naturelle chloruree sodique forte, par chauffage et extraction du sel, une eau appelee "eau-mere".Les analyses successives des auteurs, ainsi que les analyses anciennes, font apparaitre des differences qui signent principalement une fabrication non reproductible.L'experimentation a permis d'evaluer la cinetique de concentration et d'envisager un modele theorique en fonction du temps de chauffage, pour une temperature donnee et un volume d'eau rajoutee en cours d'evaporation.Le but de ces travaux est d'ameliorer un procede de fabrication deja etabli et de concilier fabrication d'eau-mere et de sel.

La veine mesenterique isolee de mouton permet de constater des interactions entre les mediateurs chimiques usuels et l'eau minerale de Barbotan.L'essai effectue dans un liquide physiologique prepare avec l'eau minerale montre une nette augmentation de la contraction maximum provoquee par la noradrenaline et l'acetylcholine, une augmentation plus faible dans le cas de l'adrenaline.Apres lavage de l'organe isole avec le liquide physiologique de reference on observe en presence de ce meme liquide une diminution importante du maximum de la contraction provoquee par la noradrenaline, une legere diminution pour l'adrenaline et une absence de variation dans le cas de I'acetylcholine.Les auteurs envisagent, a cote de l'intervention du calcium, une modulation red-Ox des taux des nucleotides cycliques soit par action au niveau de la guanylcyclase et de l'adenylcyclase soit par action au niveau de l'endothelium vasculaire.