Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailOxidation Sensitivity May Be a Useful Tool for the Detection of the Hematotoxic Potential of Newly Developed Molecules: Application to Antipsychotic Drugs
Liégeois, Jean-François ULg; Bruhwyler, J.; Petit, C. et al

in Archives of Biochemistry & Biophysics (1999), 370(1), 126-37

Some antipsychotic agents have been found to produce agranulocytosis and aplastic anemia. The oxidation phenomena and/or the formation of free radicals has been suggested to be causally related to various ... [more ▼]

Some antipsychotic agents have been found to produce agranulocytosis and aplastic anemia. The oxidation phenomena and/or the formation of free radicals has been suggested to be causally related to various hematological disorders, e.g., agranulocytosis. Using five experimental conditions, we tested the oxidative potential of compounds with and without a history of hematological side effects, e.g., agranulocytosis and aplastic anemia. A statistical analysis was undertaken for each experimental condition and a multivariate analysis combining all results was performed. Two peroxidase-induced free radical models did not successfully discriminate between drugs with and without a history of causing hematologic problems (<70%). The lipid peroxidation system provided even less satisfactory discrimination, with only 56.25% correct classification. However, an 87.5% correct classification was obtained when using the oxidation potentials of these drugs determined at pH 4.7 and at pH 7.4. A multivariate analysis taking into account the five variables provided 87.5% success in classification. The two clusters were better discriminated in terms of a "distance coefficient." In a second analysis, the putative antipsychotic pyridobenzodiazepine analogues (JL5, JL8, JL18, and JL25) were classified in the cluster of toxic compounds, while the oxa- and thiazepine analogues (JL2, JL3, and JL13) were classified as nontoxic compounds. On the other hand, a few metabolites of clozapine and fluperlapine were classified in the toxic compound group. The procedure described herein is, to our knowledge, the first which classifies molecules of different structures as well as different pharmacological profiles according to their hematotoxic potential. Such a procedure could be used to predict drug-induced hematological side effects. [less ▲]

Detailed reference viewed: 13 (2 ULg)
Full Text
Peer Reviewed
See detailOxidative degradations of oxodegradable LDPE enhanced with thermoplastic pea starch: thermo-mechanical properties, morphology, and UV-ageing studies
Raquez, Jean-Marie; Bourgeois, Aurore; Jacobs, Heidi et al

in Journal of Applied Polymer Science (2011), 122(1), 489496

The abiotic UV-degradation behavior of oxodegradable LDPE was investigated in the presence of thermoplastic pea starch (TPPS) in this study. Oxodegradable LDPE was first melt-blended with thermoplastic ... [more ▼]

The abiotic UV-degradation behavior of oxodegradable LDPE was investigated in the presence of thermoplastic pea starch (TPPS) in this study. Oxodegradable LDPE was first melt-blended with thermoplastic pea starch (TPPS) using an internal mixing chamber to enhance the abiotic oxidative degradation of oxodegradable LDPE. Because of their different affinity, maleated polyethylene was added as compatibilizer. Tensile properties, thermal properties, and morphology of resulting melt-blends were determined at different content in TPPS. High content in TPPS (40 wt %) could be readily added to oxodegradable LDPE without affecting the tensile properties of resulting melt-blends. UV-ageing studies on compatibilized TPPS/oxodegradable LDPE melt-blends were carried out by Attenuated Total Reflectance infrared spectroscopy (ATR-FTIR), Dynamic Thermomechanical Analyses (DMTA) and Differential Scanning Calorimetry (DSC) under abiotic conditions. These results suggested a synergistic effect on the UV-ageing of TPPS-based melt-blends provided by both components during the first stage of UV-irradiation. [less ▲]

Detailed reference viewed: 22 (0 ULg)
Full Text
Peer Reviewed
See detailOxidative induction time: a quality assurance measurement to predict environmental stress-cracking
Courard, Luc ULg; Rigo, Jean-Marie ULg

in De Groot, M.B.; Den Hoedt, G.; Termaat, R.J. (Eds.) Proceedings of the 1st European Geosynthetics Conference EUROGEO 1 (1996)

Detailed reference viewed: 14 (1 ULg)
Full Text
See detailOxidative phosphorylation: Building blocks and related components
Cardol, Pierre ULg; Figueroa, Francisco; Remacle, Claire ULg et al

in Stern, David; Harris, Elizabeth; Witman, George (Eds.) The Chlamydomonas Sourcebook 3-vol set, 1-3 (2009)

Detailed reference viewed: 12 (3 ULg)
Full Text
Peer Reviewed
See detailOxidative Processes in Human Promonocytic Cells (Thp-1) after Differentiation into Macrophages by Incubation with Chlamydia Pneumoniae Extracts
Mouithys-Mickalad, Ange ULg; Deby-Dupont, Ginette; Nys, Monique ULg et al

in Biochemical and Biophysical Research Communications (2001), 287(3), 781-8

Human monocytes differentiated into macrophages by Chlamydia pneumoniae were able to oxidize blood lipoproteins, as discovered by Kalayoglu et al. (1998). Using a model of human promonocytic cells (THP-1 ... [more ▼]

Human monocytes differentiated into macrophages by Chlamydia pneumoniae were able to oxidize blood lipoproteins, as discovered by Kalayoglu et al. (1998). Using a model of human promonocytic cells (THP-1), the cells were differentiated into macrophages by preincubation with C. pneumoniae extract, and further stimulated by phorbol myristate acetate. In these conditions, the differentiated cells oxidized a thiol compound and released superoxide anion as demonstrated respectively by gas liquid chromatography and electron spin resonance. The thiol oxidation and superoxide anion release were inhibited by diphenyliodonium, a NADPH oxidase and NOsynthase inhibitor, proving that the respiratory burst and the NOsynthase were involved in the oxidation processes occurring in the differentiated THP-1. The role of H(2)O(2) (derived from superoxide anion) was indicated by the enhancing effect of a peroxidase on the thiol oxidation. The presence of alpha-tocopherol in the surrounding medium strongly diminished the oxidation of the thiol target. [less ▲]

Detailed reference viewed: 32 (7 ULg)
Full Text
Peer Reviewed
See detailOxidative Stress in Clinical Situations--Fact or Fiction?
Pincemail, Joël ULg; Defraigne, Jean-Olivier ULg; Limet, Raymond ULg

in European Journal of Anaesthesiology (1996), 13(3), 219-34

Detailed reference viewed: 9 (0 ULg)
Full Text
Peer Reviewed
See detailOxidative stress in equine medicine - Current knowledge
Kirschvink, Nathalie; Lekeux, Pierre ULg

in Pferdeheilkunde (2002), 18(6), 569-573

Oxidative stress has become of increasing interest in research and human medicine. Oxidants or reactive oxygen species are generated by metabolic reactions and play an important role for the immune ... [more ▼]

Oxidative stress has become of increasing interest in research and human medicine. Oxidants or reactive oxygen species are generated by metabolic reactions and play an important role for the immune defence and the "redox-regulation" of gene expression, In physiological conditions, different categories of antioxidants maintain the equilibrium between the pro-oxidant burden and the endogenous antioxidant defence. However, when an imbalance between oxidants and antioxidants in favour of oxidants occurs, oxidative stress might induce irreversible lesions that can be evidenced and characterised by oxidant markers. In equine medicine, it has been shown that oxidative stress is occurring in lower airway disease and equine motor neuron disease. Moreover, adopted antioxicants therapy appears to have a beneficial effect on the antioxidant-oxidant imbalance. Exercise-induced oxidative stress and its impact on animal welfare and performance are also under investigation in equine sports medicine, Oxidative stress has been demonstrated to cepend on exercise type, intensity and duration. It might be modulated by training and/or adopted antioxidant therapy, aiming to maintain the antioxidant-oxidant equilibrium and thereby to improve animal welfare. [less ▲]

Detailed reference viewed: 24 (0 ULg)
Full Text
Peer Reviewed
See detailOxidative Stress in the Cochlea: An Update.
Poirrier, Anne-Lise ULg; Pincemail, Joël ULg; Van Den Ackerveken, P. et al

in Current Medicinal Chemistry (2010)

This paper will focus on understanding the role and action of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the molecular and biochemical pathways responsible for the regulation of ... [more ▼]

This paper will focus on understanding the role and action of reactive oxygen species (ROS) and reactive nitrogen species (RNS) in the molecular and biochemical pathways responsible for the regulation of the survival of hair cells and spiral ganglion neurons in the auditory portion of the inner ear. The pivotal role of ROS/RNS in ototoxicity makes them potentially valuable candidates for effective otoprotective strategies. In this review, we describe the major characteristics of ROS/RNS and the different oxidative processes observed during ototoxic cascades. At each step, we discuss their potential as therapeutic targets because an increasing number of compounds that modulate ROS/RNS processing or targets are being identified. [less ▲]

Detailed reference viewed: 35 (7 ULg)
Full Text
Peer Reviewed
See detailOxidative stress in the liver and the brain of rats in fulminant hepatic failure
Detry, Olivier ULg; Gaspar, Yves; Cheramy-Bien, Jean-Paul ULg et al

in Transplantation Proceedings (2005), 37(6, Jul-Aug), 2883-2885

The etiological mechanisms of brain edema in fulminant hepatic failure are incompletely understood. In a surgical model of fulminant hepatic failure in the rat, we tested whether oxidative stress may be ... [more ▼]

The etiological mechanisms of brain edema in fulminant hepatic failure are incompletely understood. In a surgical model of fulminant hepatic failure in the rat, we tested whether oxidative stress may be involved in the early steps of brain edema. Moreover, we took advantage of this model to determine if oxidative stress may be involved in the hepatocyte dysfunction observed in the setting of fulminant hepatic failure. Oxidative stress was evaluated by measurement of tissue ascorbic acid in the brain and liver of rats at 6 hours after induction of fulminant hepatic failure versus in control or partially hepatectomized rats. After 6 hours, the level of ascorbic acid was not different in the brain tissue of the various groups, indicating no oxidative stress. The liver showed a significant decrease in ascorbic acid levels, both in ischemic and nonischemic liver tissue, suggesting that oxidative stress might be involved in the failure of liver regeneration in fulminant hepatic failure. In this rat model no oxidative stress was demonstrated in the brain during the early phase of fulminant liver failure. [less ▲]

Detailed reference viewed: 34 (3 ULg)
Full Text
See detailOxidative stress status in top soccer players
Pincemail, Joël ULg; Bonjean, K.; Cayeux, C. et al

in Free Radical Biology & Medicine (2002), 33(Suppl. 1), 249-249

Detailed reference viewed: 3 (0 ULg)
Peer Reviewed
See detailOxidative stress which occurs during chorioamnionitis induces production of prostaglandins by uterus
Temma-Asano, Kumiko; Shimoya, Koichiro; Tskitishvili, Ekaterine ULg et al

Poster (2005)

Detailed reference viewed: 21 (0 ULg)
Full Text
Peer Reviewed
See detailOxidative stress-induced S100B protein from placenta and amnion affects soluble Endoglin release from endothelial cells.
Tskitishvili, Ekaterine ULg; Sharentuya, Namuxila; Temma-Asano, Kumiko et al

in Molecular Human Reproduction (2010), 16(3), 188-99

Oxidative stress with elevated intracellular Ca(2+) concentration as well as endothelial dysfunction is a component of pre-eclampsia. Our aim was to investigate the oxidative stress-dependent expression ... [more ▼]

Oxidative stress with elevated intracellular Ca(2+) concentration as well as endothelial dysfunction is a component of pre-eclampsia. Our aim was to investigate the oxidative stress-dependent expression of Endoglin and Ca(2+)-binding S100B protein from villous and amniotic tissue cultures, and to assess sEng expression from S100B protein-stimulated endothelial cells. We initially examined Endoglin and Hydroxy-nonenal-(HNE)-modified proteins in the placentas and amnion obtained from women with pre-eclampsia (n = 8), and healthy controls (n = 8) by immunohistochemistry. To examine oxidative stress and the S100B protein effect on sEng expression from endothelial cells, normal villous and amniotic tissue cultures were stimulated by 4-HNE, sodium fluoride and xanthine/xanthine oxidase, whereas human umbilical vein endothelial cell cultures were treated with S100B protein in a dose- and time-dependent manner at 37 degrees C in an environment of 95% air and 5% of CO(2). Culture supernatants were assessed using ELISA. Cell viability was determined using MTS assay. The concentrations of sEng and S100B protein were significantly increased in the villous and amniotic tissue culture supernatants under oxidative stress. S100B protein-stimulated endothelial cells released sEng into conditioned media with a significantly higher expression levels at a concentration of 200 pM-20 nM S100B by 2 h, whereas treated with 200 nM of S100B endothelial cells significantly expressed sEng by 12 h and stimulated the cell proliferation by the same period of time. Our findings show that oxidative stress affects sEng and S100B protein expression from villous and amniotic tissues, and picomolar and low nanomolar concentrations of S100B protein significantly up-regulate sEng release from endothelial cells leading to endothelial dysfunction. [less ▲]

Detailed reference viewed: 52 (13 ULg)
Full Text
Peer Reviewed
See detailOxidative stress-mediated iNKT-cell activation is involved in COPD pathogenesis.
Pichavant, M.; Remy, G.; Bekaert, Sandrine ULg et al

in Mucosal Immunology (2013)

Chronic obstructive pulmonary disease (COPD) is a major clinical challenge mostly due to cigarette smoke (CS) exposure. Invariant natural killer T (iNKT) cells are potent immunoregulatory cells that have ... [more ▼]

Chronic obstructive pulmonary disease (COPD) is a major clinical challenge mostly due to cigarette smoke (CS) exposure. Invariant natural killer T (iNKT) cells are potent immunoregulatory cells that have a crucial role in inflammation. In the current study, we investigate the role of iNKT cells in COPD pathogenesis. The frequency of activated NKT cells was found to be increased in peripheral blood of COPD patients relative to controls. In mice chronically exposed to CS, activated iNKT cells accumulated in the lungs and strongly contributed to the pathogenesis. The detrimental role of iNKT cells was confirmed in an acute model of oxidative stress, an effect that depended on interleukin (IL)-17. CS extracts directly activated mouse and human dendritic cells (DC) and airway epithelial cells (AECs) to trigger interferongamma and/or IL-17 production by iNKT cells, an effect ablated by the anti-oxidant N-acetylcystein. In mice, this treatment abrogates iNKT-cell accumulation in the lung and abolished the development of COPD. Together, activation of iNKT cells by oxidative stress in DC and AECs participates in the development of experimental COPD, a finding that might be exploited at a therapeutic level.Mucosal Immunology advance online publication, 30 October 2013; doi:10.1038/mi.2013.75. [less ▲]

Detailed reference viewed: 12 (5 ULg)
Peer Reviewed
See detailOxobenzopyran derivatives as thrombin inhibitors
Bourdel, F.; Lacan, F.; Doucet, C. et al

Poster (2000, September)

Detailed reference viewed: 2 (0 ULg)
Full Text
Peer Reviewed
See detailOxoglutarate translocator of rat-heart mitochondria: regulation by aspartate.
Sluse, Francis ULg; Duyckaerts, Claire ULg; Sluse-Goffart, Claudine et al

in FEBS Letters (1980), 120

Detailed reference viewed: 5 (0 ULg)
Full Text
See detailL'oxydation des poudres: un défi pour l'avenir
Blecker, Christophe ULg

Poster (2014, January 27)

Detailed reference viewed: 4 (0 ULg)
Peer Reviewed
See detailOxydation photochimique de lixiviats de décharge
Deswaef, Sophie; Baidak, Alexandre; Crine, Michel ULg

in Tribune de l'Eau (La) (1997), 590-591

Detailed reference viewed: 36 (4 ULg)
Full Text
Peer Reviewed
See detailOxygen and reactive oxygen species in cartilage degradation: friends or foes?
Henrotin, Yves ULg; Kurz, B.; Aigner, Thomas

in Osteoarthritis and Cartilage (2005), 13(8), 643-54

OBJECTIVES: This review is focused on the influence of oxygen and derived reactive species on chondrocytes aging, metabolic function and chondrogenic phenotype. METHODS: A systematic computer-aided search ... [more ▼]

OBJECTIVES: This review is focused on the influence of oxygen and derived reactive species on chondrocytes aging, metabolic function and chondrogenic phenotype. METHODS: A systematic computer-aided search of the Medline database. RESULTS: Articular cartilage is an avascular tissue, and consequently oxygen supply is reduced. Although the basal metabolic functions of the cells are well adapted to hypoxia, the chondrocyte phenotype seems to be oxygen sensitive. In vitro, hypoxia promotes the expression of the chondrogenic phenotype and cartilage-specific matrix formation, indicating that oxygen tension is probably a key parameter in chondrocyte culture, and particularly in the context of tissue engineering and stem cells transplantation. Besides the influence of oxygen itself, reactive oxygen species (ROS) play a crucial role in the regulation of a number of basic chondrocyte activities such as cell activation, proliferation and matrix remodeling. However, when ROS production exceeds the antioxidant capacities of the cell, an "oxidative stress" occurs leading to structural and functional cartilage damages like cell death and matrix degradation. CONCLUSIONS: This paper is an overview of the in vitro and in vivo studies published on the influence of oxygen and derived reactive species on chondrocyte aging, metabolic function, and the chondrogenic phenotype. It shows, that oxygen and ROS play a crucial role in the control of cartilage homeostasis and that at this time, the exact role of "oxidative stress" in cartilage degradation still remains questionable. [less ▲]

Detailed reference viewed: 9 (0 ULg)
See detailOxygen budget and associated processes in the regulated Mosel river. Models intercomparison
Garnier, Josette; Billen, Gilles; Schoell, A. et al

in Garnier, Josette; Mouchel, Jean-Marie (Eds.) Man and river systems: the functioning of river systems at the basin scale (2000)

During summer, channelized sectors of the Mosel and Saar rivers undergo severe oxygen depletion episodes that compromise their ecological value. A programme was launched by the International Commission ... [more ▼]

During summer, channelized sectors of the Mosel and Saar rivers undergo severe oxygen depletion episodes that compromise their ecological value. A programme was launched by the International Commission for the Protection of river Mosel and Saar (ICPMS) in order to identify the causes of this situation. All processes involved in the oxygen budget, including photosynthesis, algal, bacterial, zooplanktonic, zoobenthic respiration and nitrification, were investigated, and oxygen budgets for different seasonal situations were established. In close connection with these field investigations, three different mathematical models of the ecological functioning of the river system were implemented: the BfG model of the Saar and Mosel Rivers , the ULg Meuse model, adapted to the river Mosel, and the Mosarel model, resulting from the application to the Mosel-Saar river system of the RIVERSTRAHLER modelling approach We here describe the common features and differences in the conception of these models and present a few examples of their results. [less ▲]

Detailed reference viewed: 10 (3 ULg)