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See detailOxytocin synthesis and oxytocin receptor expression by cell lines of human small cell carcinoma of the lung stimulate tumor growth through autocrine/paracrine signaling
Pequeux, Christel ULg; Breton, Christophe; Hendrick, Jean-Claude et al

in Cancer Research (2002), 62(16), 4623-4629

The objective of the present work was to investigate the existence of an oxytocin (OT)-mediated autocrine/paracrine signaling upon small cell carcinoma of the lung (SCCL) cell growth. In that view, OT ... [more ▼]

The objective of the present work was to investigate the existence of an oxytocin (OT)-mediated autocrine/paracrine signaling upon small cell carcinoma of the lung (SCCL) cell growth. In that view, OT receptor (OTR) expression, concomitant with OT synthesis and secretion, was evidenced on three different SCCL cell lines (DMS79, H146, and H345) and related to the vasopressin (VP) system. Specific OT, VP, OTR, Via VP receptor (V1aR), and V1b/V3 VP receptor (V1bR/V3R) transcripts were identified by reverse transcription-.PCR in all cell lines studied. Binding of I-125-(d(CH2)(5)(1),Tyr(Me)(2), Thr(4), Orn(3),Tyr(9)-NH2)-vasotocin (OVTA) was observed on all SCCL cell lines, with a K-d (dissociation constant) ranging from 0.025-0.089 nm, depending; on the cell line and the analytical method. Selectivity of I-125-OVTA binding was confirmed by displacement curves obtained with various OTR and VP receptor agonists and antagonists (OT, OVTA, L-371,257, VP, F180). Immunocytochemistry identified cellular OT and VP, and peptide secretion was measured in supernatants of SCCL cultures. [H-3]Thymidine incorporations, applied on H345 cells, demonstrated a dose-dependent mitogenic effect of exogenous OT (1 and 100 nM) that was abolished by the OTR antagonist OVTA. A decrease of proliferation was also observed with OVTA alone, showing a functional mitogenic effect of tumor-derived OT. Taken together, these observations demonstrate the existence of a functional OT-mediated autocrine/paracrine signaling actively implicated in growth and development of SCCL tumors. Furthermore, these findings point to the potential of OT antagonists for development as therapeutic agents for the treatment of SCCL. [less ▲]

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See detailOXYTOCIN, VASOPRESSIN AND ANXIETY IN MAJOR DEPRESSION: AGO-ANTAGONIST NEUROHROMONES
Scantamburlo, Gabrielle ULg; Hansenne, Michel ULg; Fuchs, Sonia et al

in European Neuropsychopharmacology (2006), 16

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See detailOxytocin- and vasopressin-induced growth of human small-cell lung cancer is mediated by the mitogen-activated protein kinase pathway
Pequeux, Christel ULg; Keegan, B. P.; Hagelstein, M. T. et al

in Endocrine-Related Cancer (2004), 11(4), 871-885

Malignant growth of small-cell lung carcinoma is promoted by various neuroendocrine autocrine/paracrine loops. Therefore, to interfere with this mitogenic process, it is crucial to elucidate the ... [more ▼]

Malignant growth of small-cell lung carcinoma is promoted by various neuroendocrine autocrine/paracrine loops. Therefore, to interfere with this mitogenic process, it is crucial to elucidate the mechanisms involved. It is known that the oxytocin (OT) and vasopressin (VP) genes, normally transcriptionally restricted in their expression, are activated in small-cell lung cancer (SCLC), concomitantly with expression of their receptors (OTR, V1aR, V1bR/V3R and V2R). The aim of the present study was to characterize, in concentrations close to physiological and pharmacological conditions, intracellular signalling events triggered by OT and VP binding to their specific receptors in SCLC cells and to identify factors mediating OT- and VP-induced mitogenic effects on SCLC. Known agonists for OTR ([Thr(4),GlY(7)]OT) and V1aR (F180), in addition to OT and VP, were able to elicit increases in cytosolic Ca2+ levels and this effect could be blocked using an OTR antagonist (OVTA) or a V1aR antagonist (SR49059) respectively. There was no activation of the cAMP pathway detected after VP, dDAVP (a V2R agonist), or OT treatment. Stimulation of SCLC cells with OT and VP led to an increase of extracellular signal-regulated kinase (ERK) 1/2 phosphorylation, maximal at 5 min, and the subsequent phosphorylation of its downstream target p90 ribosomal S6 kinase (p90(RSK)). Pre-incubation with OVTA and SR49059, and with inhibitors of phospholipase C (PLC), protein kinase C (PKC), mitogen-activated protein kinase/ERK kinase (MEK) 1/2 and a Ca2+ chelator significantly reduced OT- and VP-induced ERK1/2 phosphorylations. OVTA, SR49059 as well as MEK1/2 and PKC inhibitors also downregulated OT- and VP-induced p90RSK phosphorylation. In [H-3]thymidine-uptake 2, experiments, we subsequently observed that PLC, Ca2+, PKC and ERK1/2 are absolutely required for the OT- and VP-stimulated SCLC cellular growth process. In conclusion, the results presented here indicate that OT- and VP-induced mitogenic effects on SCLC are respectively mediated by OTR and V1aR signalling and that this mitogenic signalling passes through the phosphorylation of ERK1/2 and p90(RSK) in a PLC-, Ca2+-, PKC- and MEK1/2-dependent pathway. [less ▲]

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See detailOxytocin: From milk ejection to maladaptation in stress response and psychiatric disorders. A psychoneuroendocrine perspective.
Scantamburlo, Gabrielle ULg; Ansseau, Marc ULg; Geenen, Vincent ULg et al

in Annales d'Endocrinologie (2009), 70(6), 449-54

Oxytocin (OT) is implicated in stress reduction as well as in social behavior. It inhibits the stress-induced activity of the hypothalamic-pituitary adrenal axis responsiveness. OT is involved in social ... [more ▼]

Oxytocin (OT) is implicated in stress reduction as well as in social behavior. It inhibits the stress-induced activity of the hypothalamic-pituitary adrenal axis responsiveness. OT is involved in social affiliation, sexual and maternal-infant binding, anxiety, mood, feeding control and memory. Several lines of evidence suggest a role of OT in psychiatric disorders. Various psychiatric disorders are strongly influenced by social variables, such as panic attacks, depression and early childhood autism, and seem to exhibit a particularly close connection with the brain dynamics that underlie social emotions. This paper proposes an overview of OT in psychiatric disorders through the links with the stress response and prosocial behavior. [less ▲]

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See detailOzone adaptation in calves is associated with impaired accumulation of granulocytes in the lung
Fievez, Laurence ULg; Kirschvink, Nathalie; Dogné, S. et al

in Proceedings: Comparative Respiratory Society Meeting (2001)

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See detailOzone et asthme: un couple dans l'air du temps
Kleis, S.; Louis, Renaud ULg; Bartsch, Pierre ULg

in Revue Médicale de Liège (2003), 58(3), 132-8

Ozone is a pollutant the production of which depends on weather conditions and car engine combustion. Numerous epidemiological studies have indicated that high ozone levels correlated with morbidity in ... [more ▼]

Ozone is a pollutant the production of which depends on weather conditions and car engine combustion. Numerous epidemiological studies have indicated that high ozone levels correlated with morbidity in asthma. Experimental studies have shown that exposure of healthy subjects and asthmatics to ozone levels comparable to those measured in ambient air during hot summer days can generate respiratory symptoms, neutrophilic airways inflammation and lung function impairment. Lung function changes following ozone exposure are more pronounced in asthmatics and are dependent on the duration and intensity of exposure, a previous exposure and the nutritional status of the subjects. The airway epithelial cell layer is likely to play a pivotal role in initiating the inflammatory process following ozone exposure. Control of ambient air ozone levels must be a target for public health authorities. [less ▲]

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See detailOzone tropospheric and stratospheric trends (1995-2011) at six ground- based FTIR stations (34°S to 79°N)
Vigouroux, Corinne; Demoulin, Philippe ULg; Hase, Frank et al

Poster (2011, November)

Five ground-based stations in Western Europe, from 79°N to 28°N, all part of the Network for the Detection of Atmospheric Composition Change (NDACC), have joined their efforts to homogenize and optimize ... [more ▼]

Five ground-based stations in Western Europe, from 79°N to 28°N, all part of the Network for the Detection of Atmospheric Composition Change (NDACC), have joined their efforts to homogenize and optimize the retrievals of ozone profiles from FTIR (Fourier transform infrared) solar absorption spectra. Using the optimal estimation method, distinct vertical information can be obtained in four layers: ground—10 km, 10—18 km, 18—27 km, and 27—42 km, in addition to total column amounts. A bootstrap resampling method has been implemented to determine annual partial and total column trends. Vigouroux et al. (2008) applied this method to the ozone data and discussed the trends of the total columns and of the partial columns in the above four layers, over the period 1995-2004. The updated trends for the 1995-2009 period has been published in the WMO 2010 report. Here, we present the updated trends for the 1995-mid-2011 period, for the five European stations but also for a southern hemisphere station, Wollongong (34°S), which recently joined this ozone network. [less ▲]

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See detailOzone tropospheric and stratospheric trends (1995-2011) at six ground-based FTIR stations (28°N to 79°N)
Vigouroux, Corinne; De Mazière, Martine; Demoulin, Philippe ULg et al

Poster (2012, August)

Five ground-based stations in Western Europe, from 79°N to 28°N, all part of the Network for the Detection of Atmospheric Composition Change (NDACC), have joined their efforts to homogenize and optimize ... [more ▼]

Five ground-based stations in Western Europe, from 79°N to 28°N, all part of the Network for the Detection of Atmospheric Composition Change (NDACC), have joined their efforts to homogenize and optimize the retrievals of ozone profiles from FTIR (Fourier transform infrared) solar absorption spectra. Using the optimal estimation method, distinct vertical information can be obtained in four layers: ground—10 km, 10—18 km, 18—27 km, and 27—42 km, in addition to total column amounts. Vigouroux et al. (2008) applied a bootstrap resampling method to the ozone data to determine the trends of the total columns and of the partial columns in the above four layers, over the period 1995-2004. The updated trends for the period 1995-2009 have been published in the WMO 2010 report. Here, we present the updated trends, obtained using the bootstrap resampling method, for the 1995-mid-2011 period, for the five European stations and also for the station Thule, Greenland (77°N), which has joined this effort. The trends have also been estimated using a multiple regression model including the Quasi Biennial Oscillation (QBO) and the solar flux as explanatory variables. The trends obtained by the two methods will be compared and discussed. One of the major results is the significant positive trend observed in the upper stratosphere at the station Jungfraujoch (47°N), which provides a sign of ozone recovery at mid-latitudes. Significant positive trends are also observed in the upper stratosphere at the high latitude stations. [less ▲]

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See detailOzone tropospheric and stratospheric trends (1995-2012) at six ground-based FTIR stations (28°N to 79°N)
Vigouroux, Corinne; De Mazière, Martine; Demoulin, Philippe ULg et al

Poster (2013, April)

In the frame of the Network for the Detection of Atmospheric Composition Change (NDACC), contributing ground-based stations have joined their efforts to homogenize and optimize the retrievals of ozone ... [more ▼]

In the frame of the Network for the Detection of Atmospheric Composition Change (NDACC), contributing ground-based stations have joined their efforts to homogenize and optimize the retrievals of ozone profiles from FTIR (Fourier transform infrared) solar absorption spectra. Using the optimal estimation method, distinct vertical information can be obtained in four layers: ground-10 km, 10-18 km, 18-27 km, and 27-42 km, in addition to total column amounts. In a previous study, Vigouroux et al. (2008) applied a bootstrap resampling method to determine the trends of the ozone total and four partial columns, over the period 1995-2004 at Western European stations. The updated trends for the period 1995-2009 have been published in the WMO 2010 report. Here, we present the updated trends and their uncertainties, for the 1995-2012 period, for the different altitude ranges, above five European stations (28°N-79°N) and above the station Thule, Greenland (77°N). In this work, the trends have been estimated using a multiple regression model including some explanatory variables responsible for the ozone variability, such as the Quasi Biennial Oscillation (QBO), the solar flux, the Arctic Oscillation (AO) or El Niño-Southern Oscillation (ENSO). A major result is the significant positive trend of ozone in the upper stratosphere, observed at the Jungfraujoch (47°N), which is a typical mid-latitude site, as well as at the high latitude stations. This positive trend in the upper stratosphere at Jungfraujoch provides a sign of ozone recovery at mid-latitudes. [less ▲]

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See detailOZONE, CLIMATE AND BIOSPHERIC ENVIRONMENT IN THE ANCIENT OXYGEN-POOR ATMOSPHERE
François, Louis ULg; Gérard, Jean-Claude ULg

in Planetary and Space Science (1988), 36(12), 1391-1414

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See detailOzone-Depleting Substances (ODSs) and Related Chemicals (Chapter 1)
Montzka, S. A.; Reimann, S.; Engel, A. et al

in Nohende Ajavon, Ayité-Lô; Newmann, Paul A.; Pyle, John A. (Eds.) et al Scientific Assessment of Ozone Depletion: 2010 (2011)

The amended and adjusted Montreal Protocol continues to be successful at reducing emissions and atmospheric abundances of most controlled ozone-depleting substances (ODSs).

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See detailOzone-Induced Stimulation of Pulmonary Sympathetic Fibers: A Protective Mechanism against Edema
Delaunois, Annie ULg; Segura, P.; Dessy, Cécile ULg et al

in Toxicology and Applied Pharmacology (1997), 147(1), 71-82

Tropospheric ozone exerts well-described toxic effects on the respiratory tract. Less documented, by contrast, is the ability of ozone to induce protective mechanisms against agents that are toxic to the ... [more ▼]

Tropospheric ozone exerts well-described toxic effects on the respiratory tract. Less documented, by contrast, is the ability of ozone to induce protective mechanisms against agents that are toxic to the lungs. In particular, interactions between ozone and the sympathetic nervous system have never been considered. Using a model of permeability edema in isolated perfused rabbit lungs, we report here that, immediately after exposure of rabbits to 0.4 ppm ozone for 4 hr, the pulmonary microvascular responses to acetylcholine and substance P are completely blocked. Several lines of evidence, including partial inhibition of the ozone-induced protective effect by several drugs (alpha2- and beta-adrenergic antagonists, neuropeptide Y antagonist, guanethidine), measured levels of released catecholamines in blood and urine and the in vitro response of isolated lungs exposed to 0.4 ppm ozone all seem to suggest that ozone can stimulate pulmonary adrenergic fibers and induce the local release of catecholamines and neuropeptide Y, this resulting in transient protection against pulmonary edema. We also showed that, 48 hr after the exposure, ozone increased the baseline microvascular permeability and the response to low concentrations of acetylcholine [less ▲]

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See detailL'ozone: une alternative au traitement chirurgical de la carie ?
Guéders, Audrey; Geerts, Sabine ULg

in Actualités Dentaires de l'Université de Liège (2007), 37

L'ozone possède des propriétés intéressantes tant dans le domaine médical que dans le domaine de la dentisterie. Ce gaz est capable d'éradiquer un certain nombre de bactéries, de virus et de champignons ... [more ▼]

L'ozone possède des propriétés intéressantes tant dans le domaine médical que dans le domaine de la dentisterie. Ce gaz est capable d'éradiquer un certain nombre de bactéries, de virus et de champignons après seulement 5 secondes de son application. Depuis quelques années, la firme Kavo propose un disposif (HealOzone®) générateur d'ozone spécialement conçu pour traiter les lésions carieuses non cavitaires. Cet article fait le point sur les connaissances actuelles concernant l'utilisation de l'ozone dans le traiement des caries débutantes. [less ▲]

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See detailp-[18F]MPPF, 5-HT1A antagonist: comparison to [3H]8-OH-DPAT with autoradiography
Plenevaux, Alain ULg; Weissmann, D.; Lemaire, Christian ULg et al

in Society for Neuroscience / Abstracts (1999)

p-MPPF 4-(2’-methoxyphenyl)-1-[2’-[N-(2’’-pyridinyl)-p-fluorobenzamido] ethyl]piperazine is the para-fluorobenzoyl analog of the highly selective 5-HT1A antagonist WAY-100635. The one step procedure used ... [more ▼]

p-MPPF 4-(2’-methoxyphenyl)-1-[2’-[N-(2’’-pyridinyl)-p-fluorobenzamido] ethyl]piperazine is the para-fluorobenzoyl analog of the highly selective 5-HT1A antagonist WAY-100635. The one step procedure used to label p-MPPF with fluorine-18 (cyclotron produced positron emitter of 110 min half-life) leads to a radiopharmaceutical compound easily prepared on a large scale. The preliminary evaluations conducted in rats and cats are good reason to consider p-[18F]MPPF as an interesting reversible radioligand to study the 5-HT1A receptor family in humans with positron emission tomography (PET). In this paper we report a careful comparison between p-[18F]MPPF and [3H]8-OH-DPAT with autoradiography and quantitative densitometry in the same animal. All experiments were conducted in Sprague Dawley male rats. For p-[18F]MMPF, the results were obtained ex-vivo after an intravenous injection of high specific activity radioligand (0.8-1.5 Ci/µmol) in vigil (no anesthesia), free moving and unstressed animals. For the purpose, permanent cannulation of the posterior vena cava were realized at least four days in advance. The [3H]8-OH-DPAT results were obtained in vitro on adjacent coronal sections to the one used for the p-[18F]MPPF autoradiography. Quantitative densitometry was employed to compare the values obtained in relevant brain structures (frontal cortex, lateral septum, hippocampus, dorsal raphe, entorhinal cortex and cerebellum). The plot of the p-[18F]MPPF values obtained for each structure against the [3H]8-OH-DPAT results displayed a significant linear correlation. These results demonstrate that from a qualitative as well as quantitative point of view, the binding of p-[18F]MPPF is totally comparable to the one of [3H]8-OH-DPAT. Supported by grants from INSERM/CGRI and FNRS Belgium. [less ▲]

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See detailp-[18F]MPPF, a fluoro analog of WAY-100635 for visualisation of 5-HT1A receptors in cat.
Le Bars, D.; Ginovart, N.; Hassoun, W. et al

in Journal of Labelled Compounds & Radiopharmaceuticals (1999), 42

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See detailLe p-[18F]MPPF: un nouveau ligand pour l'étude par TEP des récepteurs 5-HT1A
Ginovart, Nathalie; Le Bars, Didier; Lemaire, Christian ULg et al

Poster (1997, May 25)

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See detailp-mode Oscillations of alpha Cen A
Thoul, Anne ULg; Scuflaire, Richard ULg; Vatovez, B. et al

in Astrophysics & Space Science (2003), 284

Models of alpha Cen A & B have been computed using the masses determined by Pourbaix et al. (2002) and the data derived from the spectroscopic analysis of Neuforge and Magain (1997). The seismological ... [more ▼]

Models of alpha Cen A & B have been computed using the masses determined by Pourbaix et al. (2002) and the data derived from the spectroscopic analysis of Neuforge and Magain (1997). The seismological data obtained by Bouchy and Carrier (2001, 2002) do help improve our knowledge of the evolutionary status of the system. All the constraints are satisfied with a model which gives an age of about 6 Gyr for the binary. [less ▲]

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