Development and aging of the Kisspeptin-GPR54 system in the mammalian brain: what are the impacts on female reproductive function?

in Frontiers in Neuroendocrine Science (2013)

MiR-210 promotes a hypoxic phenotype and increases radioresistance in human lung cancer cell lines.

in Cell Death & Disease (2013), 4

The resistance of hypoxic cells to radiotherapy and chemotherapy is a major problem in the treatment of cancer. Recently, an additional mode of hypoxia-inducible factor (HIF)-dependent transcriptional ... [more ▼]

The resistance of hypoxic cells to radiotherapy and chemotherapy is a major problem in the treatment of cancer. Recently, an additional mode of hypoxia-inducible factor (HIF)-dependent transcriptional regulation, involving modulation of a specific set of micro RNAs (miRNAs), including miR-210, has emerged. We have recently shown that HIF-1 induction of miR-210 also stabilizes HIF-1 through a positive regulatory loop. Therefore, we hypothesized that by stabilizing HIF-1 in normoxia, miR-210 may protect cancer cells from radiation. We developed a non-small cell lung carcinoma (NSCLC)-derived cell line (A549) stably expressing miR-210 (pmiR-210) or a control miRNA (pmiR-Ctl). The miR-210-expressing cells showed a significant stabilization of HIF-1 associated with mitochondrial defects and a glycolytic phenotype. Cells were subjected to radiation levels ranging from 0 to 10 Gy in normoxia and hypoxia. Cells expressing miR-210 in normoxia had the same level of radioresistance as control cells in hypoxia. Under hypoxia, pmiR-210 cells showed a low mortality rate owing to a decrease in apoptosis, with an ability to grow even at 10 Gy. This miR-210 phenotype was reproduced in another NSCLC cell line (H1975) and in HeLa cells. We have established that radioresistance was independent of p53 and cell cycle status. In addition, we have shown that genomic double-strand breaks (DSBs) foci disappear faster in pmiR-210 than in pmiR-Ctl cells, suggesting that miR-210 expression promotes a more efficient DSB repair. Finally, HIF-1 invalidation in pmiR-210 cells removed the radioresistant phenotype, showing that this mechanism is dependent on HIF-1. In conclusion, miR-210 appears to be a component of the radioresistance of hypoxic cancer cells. Given the high stability of most miRNAs, this advantage could be used by tumor cells in conditions where reoxygenation has occurred and suggests that strategies targeting miR-210 could enhance tumor radiosensitization. [less ▲]

Stepped spillway Downstream of a Piano Key Weir - Critical length for uniforme flow

in Bung, Daniel B.; Pagliara, Stefano (Eds.) International Workshop on Hydraulic Design of Low-Head Structures (2013)

Recent researches showed the rapid aeration of the flow downstream of piano key weirs. This could be related to the specific geometric features of the structure, creating several interacting flows and ... [more ▼]

Recent researches showed the rapid aeration of the flow downstream of piano key weirs. This could be related to the specific geometric features of the structure, creating several interacting flows and jets downstream. In order to validate this assumption, an experimental research has been carried out at the Laboratory of Engineering Hydraulics, University of Liège. The main objective of the study was to an-alyze the energy dissipation occurring in skimming flow conditions on a stepped spillway downstream of a piano key weir (PKW). Comparison with energy dissipation on a stepped spillway downstream of a standard ogee crested weir has been performed. An indirect method has been used to determine the resid-ual energy at the spillway toe. The results show that uniform flow conditions are reached faster on a stepped spillway downstream of a PWK compared to the length needed downstream of a standard ogee crested weir. Extrapolation of the results to prototype flow conditions is also discussed with regards to scale effects influence. [less ▲]

La Littérature à l'ombre. Sociologie du Zutisme.

Book published by Classiques Garnier (2013)

Durant les derniers mois de 1871, une microsociété d’écrivains et artistes liés à la Bohème parisienne prend ses quartiers à l’Hôtel des Étrangers. En secret, les membres de ce groupuscule forment un ... [more ▼]

Durant les derniers mois de 1871, une microsociété d’écrivains et artistes liés à la Bohème parisienne prend ses quartiers à l’Hôtel des Étrangers. En secret, les membres de ce groupuscule forment un cercle, le Zutisme, et prennent part à la confection d’un manuscrit libertaire et potache, l’Album zutique, qu’ils remplissent de sonnets monosyllabiques, dizains parodiques et autres caricatures scabreuses. Les auteurs de ces textes frondeurs sont Rimbaud, Verlaine et Cros, mais aussi Valade, Cabaner et Keck. Le présent livre revient sur la genèse et les logiques de cette éphémère aventure, sur la conduite de vie collective qui s’y est développée, sur les enjeux et effets, enfin, de l’œuvre qui en est le produit. [less ▲]

Levels of polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and polychlorinated biphenyls in human milk from different regions of France

in Science of the Total Environment (2013), 452-453

Wereport on the pilot study carried out before the start of the Elfe project (French longitudinal study from childhood). A total of 44 samples of mature human milk were collected at home 8 weeks after ... [more ▼]

Wereport on the pilot study carried out before the start of the Elfe project (French longitudinal study from childhood). A total of 44 samples of mature human milk were collected at home 8 weeks after delivery. A total of 7 polychlorinated dibenzo-p-dioxins (PCDDs), 10 polychlorinated dibenzofurans (PCDFs), 12 dioxin-like (DL) polychlorinated biphenyls (PCBs), and 6 non dioxin-like (NDL)-PCBs were measured. For total TEQ (PCDD/Fs and DL-PCBs), the geometric mean concentration was 17.81 pg TEQWHO05/g lipids. Relative PCDD, PCDF, and DL-PCB contributions to the arithmetic mean TEQWHO05 were 38%, 18%, and 44%, respectively. The use of TEFWHO05 instead of TEFWHO98 resulted in a 27% reduction of the total TEQ value. Although PCDD levels did not significantly change (less than 0.5% increase), PCDF and DL-PCB levels both decreased by 35% and 38%, respectively. Levels have been compared to data obtained during a previous non-reported national study conducted in 1998 (TEFWHO98) in French lactaria (n = 244). The mean of PCDD/Fs has decreased about 39.4% (18.8 pg TEQWHO98/g lipids in 1998 vs 11.4 pg TEQWHO98/g lipids in pilot study), respectively 41.5% for PCDDs (10.6 pg TEQWHO98/g lipids in 1998 vs 6.2 pg TEQWHO98/g lipids in pilot study) and 36.7% for PCDFs (7.9 pg TEQWHO98/g lipids in 1998 vs 5.0 pg TEQWHO98/g lipids in pilot study). For the sum of the 6 NDL-PCBs, the 2007 geometric mean concentration in milk was 176.3 ng/g lipids. The arithmetic mean lipid concentration in 2007 breast milk was 26.4 g/l (range from 6.0 to 46.7 g/l). A PCDD/F and DL-PCB daily intake was estimated to be 62.3 pg TEQWHO05/kg body weight per day (85.0 pg TEQWHO98/kg bodyweight per day) for a baby of 5 kg of bodyweight fed daily with 700 ml of maternal milk containing 25 g/l of lipids. [less ▲]

Dioxin levels in fertilizers from Belgium: Determination and evaluation of the potential impact on soil contamination

in Science of the Total Environment (2013), 454-455

Dioxins are harmful Persistent Organic Pollutants (POPs) to which humans are exposed mostly via the consumption of animal products. They can enter the food chain at any stage, including crop fertilization ... [more ▼]

Dioxins are harmful Persistent Organic Pollutants (POPs) to which humans are exposed mostly via the consumption of animal products. They can enter the food chain at any stage, including crop fertilization. Fertilizers belong to several categories: synthetic chemicals providing the essential elements (mostly N, P and K) that are required by the crops but also organic fertilizers or amendments, liming materials, etc. Ninety-seven samples of fertilizers were taken in Belgium during the year 2011 and analyzed after a soft extraction procedure for polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (DL-PCBs) using GC-IDHRMS. Only small qualitative differences could be observed between the main fertilizer categories since the PCDD:PCDF:DL-PCB average ratio obtained with the results expressed in WHO 2005-TEQ was often close to 30:30:40 (typically for sewage sludge) or 40:30:30 (typically for compost). The median dioxin levels determined were generally lower than recorded previously and were the highest for sewage sludge and compost (5.6 and 5.5 ng TEQ/kg dry weight (dw), respectively). The levels in other fertilizers were lower including manure for which the median value was only 0.2 ng TEQ/kg dw. Several fertilization scenarios relying on the use of those fertilizers were assessed taking into consideration the application conditions prevailing in Belgium. From this assessment it could be concluded that the contribution of fertilizers to the overall soil contamination will be low by comparison of other sources of contamination such as atmospheric depositions. At the field scale, intensive use of compost and sewage sludge will increase dramatically the dioxin inputs compared with other fertilization practices but this kind of immission to the soil will still be relatively low compared to the dioxin atmospheric depositions. [less ▲]

Synthesis and fading of eighteenth-century Prussian blue pigments: a combined study by spectroscopic and diffractive techniques using laboratory and synchrotron radiation sources

in Journal of Synchrotron Radiation (2013), 20(3), 460--473

compte rendu de l'ouvrage Eleanor DICKEY, The Colloquia of the Hermeneumata Pseudodositheana. Volume I. Colloquia Monacensia-Einsidlensia, Leidense-Stephani, and Stephani, Cambridge, Cambridge University Press, 2012. 1 vol. 21,5 x 28,5, XI-276 p. (CAMBRIDGE CLASSICAL TEXTS AND COMMENTARIES, 49). ISBN : 978-1-107-02010-8.

in Antiquité Classique : Revue Interuniversitaire d'Etudes Classiques (2013)

Analytical determination of stress patterns in the periodontal ligament during orthodontic tooth movement.

in Medical Engineering & Physics (2013), 35(3), 403-10

A dedicated software package that allows simulation of tooth movement can lead to shortening of the treatment program in orthodontics. A first step in the development of this software is the modelling of ... [more ▼]

A dedicated software package that allows simulation of tooth movement can lead to shortening of the treatment program in orthodontics. A first step in the development of this software is the modelling of the movement of a single tooth. Forces applied to the crown of the tooth are transmitted to the alveolar bone through the periodontal ligament, stretching, and compressing the ligament, eventually resulting in tooth movement. This paper presents an analytical model that predicts stresses and strains inside this ligament by approximating the shape of the root as an elliptic paraboloid. The model input consists of 2 material parameters and 4 geometrical parameters. To assess the accuracy of the model a finite element model (FEM) was constructed to compare the results and the influence of the eccentricity of the root was studied. The results show that the model is able to successfully describe the global behavior of the PDL and, except at a region near the alveolar crest, the differences between analytical and FEM results are small. In contrast to FEM, the analytical model does not require setting up a 3D-model and creating a mesh, allowing for significantly lower computational times and reducing cost when implementing in clinical practice. [less ▲]

Mechanobiological modeling can explain orthodontic tooth movement: three case studies.

in Journal of Biomechanics (2013), 46(3), 470-7

Progress in medicine and higher expectation of quality of life has led to a higher demand for several dental and medical treatments. This increases the occurrence of situations in which orthodontic ... [more ▼]

Progress in medicine and higher expectation of quality of life has led to a higher demand for several dental and medical treatments. This increases the occurrence of situations in which orthodontic treatment is complicated by pathological conditions, medical therapies and drugs. Together with experiments, computer models might lead to a better understanding of the effect of pathologies and medical treatment on tooth movement. This study uses a previously presented mechanobiological model of orthodontic tooth displacement to investigate the effect of pathologies and (medical) therapies on the result of orthodontic treatment by means of three clinically relevant case studies looking at the effect of estrogen deficiency, the effect of OPG injections and the influence of fluoride intake. When less estrogen was available, the model predicted bone loss and a rise in the number of osteoclasts present at the compression side, and a faster bone resorption. These effects were also observed experimentally. Experiments disagreed on the effect of estrogen deficiency on bone formation, while the mechanobiological model predicted very little difference between the pathological and the non-pathological case at formation sites. The model predicted a decrease in tooth movement after OPG injections or fluoride intake, which was also observed in experiments. Although more experiments and model analysis is needed to quantitatively validate the mechanobiological model used in this study, its ability to conceptually describe several pathological conditions is an important measure for its validity. [less ▲]