In Vitro Study of the Antioxidant Properties of Nimesulide and 4-Oh Nimesulide: Effects on Hrp- and Luminol-Dependent Chemiluminescence Produced by Human Chondrocytes; Mouithys-Mickalad, Ange ; et alin Osteoarthritis and Cartilage (2000), 8(6), 419-25 OBJECTIVES: Reactive oxygen species (ROS) are now recognized to play an important role in the pathogenesis of rheumatic diseases and constitute an interesting therapeutic target for drugs. This in vitro ... [more ▼] OBJECTIVES: Reactive oxygen species (ROS) are now recognized to play an important role in the pathogenesis of rheumatic diseases and constitute an interesting therapeutic target for drugs. This in vitro study was designed to evaluate the antioxidant properties of nimesulide (NIM), a nonsteroidal antiinflammatory drug of the sulfonanilide class, and its main metabolite 4-OH nimesulide (4-OHNIM). METHODS: The scavenging effects of NIM and 4-OH NIM on hydroxyl radical ((.)OH) and superoxide anions (O(minusd)(2)) were investigated by electron spin resonance (ESR), using 5, 5-dimethylpyrroline-N-oxide (DMPO) as the spin trap agent. The quenching properties of these drugs on hypochlorite anion was studied by luminol enhanced chemiluminescence. Finally, the effects of NIM and 4-OHNIM on the reactive oxygen species production by human articular chondrocytes were recorded by HRP and luminol-enhanced chemiluminescence. RESULTS: By this method it has been demonstrated that NIM and 4-OHNIM, at concentrations ranging from 10 to 100 microM, are potent scavengers of(.)OH whereas only 4-OHNIM was capable to scavenge O(minusd)(2). Chemiluminescence generated by HOCl was also significantly and dose-dependently inhibited by both NIM and 4-OHNIM. Nevertheless, at each concentration tested, the inhibitory effect of 4-OHNIM was significantly more marked, even at the highest concentration (100 microM). Furthermore, when chondrocytes were pre-incubated for 48-96 h with NIM or 4-OHNIM, the luminol- and HRP-dependent CL produced by the cells was significantly inhibited in a dose-dependent manner. CONCLUSIONS: NIM and 4-OHNIM may protect cartilage against oxidative stress, not only by scavenging ROS but also by inhibiting their production by chondrocytes. [less ▲] Detailed reference viewed: 14 (3 ULg) In vitro study of the antioxidant properties of non steroidal anti-inflammatory drugs by chemiluminescence and electron spin resonance (ESR).Mouithys-Mickalad, Ange ; ; et alin Free Radical Research (2000), 33(5), 607-21 OBJECTIVES: To determine the antioxidant activities of nonsteroidal anti-inflammatory drugs (NSAIDS), we examined by chemiluminescence (CL) and electron spin resonance (ESR) their scavenging properties ... [more ▼] OBJECTIVES: To determine the antioxidant activities of nonsteroidal anti-inflammatory drugs (NSAIDS), we examined by chemiluminescence (CL) and electron spin resonance (ESR) their scavenging properties towards lipid peroxides, hypochlorous acid and peroxynitrite. METHODS: The antioxidant properties of nimesulide (NIM), 4-hydroxynimesulide (4-HONIM), aceclofenac (ACLO), 4-hydroxyaceclofenac (4-HOA-CLO), diclofenac (DICLO) and indomethacin (INDO) were tested on four different reactive oxygen species (ROS) generating systems: (I) phorbol-myristate acetate (PMA)-activated neutrophils, (II) Fe2+/ascorbate-induced lipid peroxidation, (III) HOCl-induced light emission, (IV) the kinetics of ONOO- decomposition followed by spectrophotometry. ROS production was monitored by luminol-enhanced CL or by ESR using two different spin traps. RESULTS: At 10 microM, ACLO, NIM, 4-HONIM, 4-HOA-CLO, and DICLO decreased luminol-enhanced CL generated by PMA-activated neutrophils. Inversely, INDO increased the luminol enhanced CL. Interestingly, hydroxylated metabolites were more potent antioxidants than the parent drugs. Furthermore, all drugs tested, excepted ACLO, lowered lipid peroxidation induced by Fe2+/ascorbate system. ACLO and DICLO, even at the highest concentration tested (100 microM), did not significantly lower HOCl induced CL, whereas the other drugs were potent scavengers. Finally, all the NSAIDS accelerated decomposition of ONOO-, suggesting a potential capacity of the molecules to scavenge peroxynitrite. CONCLUSION: The NSAIDs possess variable degrees of antioxidant activities, linked to their ability to react with HOCl, lipid peroxides or ONOO-. These antioxidant activities could offer interesting targeted side-effects in the treatment of joint inflammatory diseases. [less ▲] Detailed reference viewed: 12 (4 ULg) In vitro study of the antioxydant properties of nonsteroidal anti-inflammatory drugs by chemiluminescence and electron spin resonance (ESR)Henrotin, Yves ; Mouithys-Mickalad, Ange ; et alin Annals of the Rheumatic Diseases (2000), 59(S1), 187 Detailed reference viewed: 7 (1 ULg) In vitro study of the antioxydant properties of the nimesulide and 4OH nimesulide : effect on HRP- and luminol-dependent chemiluminescence produced by human chondrocytesHenrotin, Yves ; ; Mouithys-Mickalad, Ange et alin Annals of the Rheumatic Diseases (2000), 59(S1), 265 Detailed reference viewed: 6 (2 ULg) In vitro study of the influence of temperature, pH and Aw on the growth rate of trichoderma aspergillum; ; et al in Bulletin OILB/SROP = IOBC/WPRS Bulletin (2007), 30 Detailed reference viewed: 17 (0 ULg) In vitro study of the interactions between bovine herpesvirus 4 and the bovine host cellsVanderplasschen, Alain ![]() in Bulletin et Mémoires de l'Académie Royale de Médecine de Belgique (1999), 154 This work was devoted to the study of the interactions between bovine herpesvirus 4 (BHV-4) and bovine cells in vitro. It led to the discovery of two interesting properties of BVH-4 replication cycle ... [more ▼] This work was devoted to the study of the interactions between bovine herpesvirus 4 (BHV-4) and bovine cells in vitro. It led to the discovery of two interesting properties of BVH-4 replication cycle: first, the cellular receptor heparan sulfate was proven to mediate BVH-4 binding to target cells. This is the first description of the implication of heparan sulfate in the binding process of a gammaherpesvirus. Second, using synchronised cells, the replication of BVH-4 DNA was proven to be dependent on the S phase of the cell cycle. This dependence could explain some properties of BVH-4 infection in vitro and could play an important role in the biology of the infection in vivo. Finally, in order to produce monoclonal antibodies against BVH-4 IE1 and IE2 proteins, the genes coding for these proteins were cloned and expressed in prokaryotic cells. [less ▲] Detailed reference viewed: 1 (0 ULg) An in vitro study of the modulating activity of indole derivatives on H2O2/hemic enzyme systems.Mouithys-Mickalad, Ange ; Franck, Thierry ; et alPoster (2006, May 12) Detailed reference viewed: 20 (5 ULg) In vitro study on the effects of aceclofenac on proteoglycan and type II collagen production by human chondrocytesHenrotin, Yves ; ; et alin Osteoarthritis and Cartilage (1997), 5 Detailed reference viewed: 8 (4 ULg) In vitro survival of vitrified goat embryos: comparison of two vitrification methods; ; et al in Proceedings: 17th Annual Meeting AETE (2001) Detailed reference viewed: 6 (1 ULg) In vitro survival of vitrified goat embryos: comparison of two vitrification methods; ; et al in Proceedings: 17e Réunion A.E.T.E. (2001) Detailed reference viewed: 2 (0 ULg) In vitro susceptibility of Clostridium perfringens isolated from farm animals to growth-enhancing antibiotics.; Daube, Georges ; et alin Journal of Applied Bacteriology (1993), 75 Detailed reference viewed: 26 (3 ULg) In Vitro Susceptibility Testing of Aspergillus fumigatus against Posaconazole: Comparison of NCCLS M38-P and E-Test MethodsHayette, Marie-Pierre ; ; Seidel, Laurence et alPoster (2002, September) Posaconazole is a second-generation triazole and structural analogue of itraconazole. This drug has fungicidal activity against yeasts and filamentous fungi. The aim of our study was to evaluate E-test ... [more ▼] Posaconazole is a second-generation triazole and structural analogue of itraconazole. This drug has fungicidal activity against yeasts and filamentous fungi. The aim of our study was to evaluate E-test method for in vitro susceptibility testing of Aspergillus fumigatus isolates against posaconazole. METHODS: A total of 121 isolates of A. fumigatus were selected as follows: 106 clinical strains from colonized patients, 18 from patients with invasive aspergillosis and 7 environmental isolates. Their in vitro susceptibility was evaluated by E-test (Abbiodisk, Sweden) and compared with NCCLS microdilution reference method (M38-P). Both tests were performed with RPMI 1640 medium at 35 degrees C. MIC values were read after 24h (MIC-24h) and 48h (MIC-48h) incubation time by E-test method. Two MIC endpoints were determined by NCCLS method: 1.no visible reduction of growth (MIC-0); 2. 50% reduction (or more) of growth (MIC-2). Three A. fumigatus reference strains (IHEM 5734, 6149 and 13935) were included as control. RESULTS: Geometric mean MICs (microg/ml) were respectively 0.02 for E-test at 24h and 0.029 at 48h. MIC-0 and MIC-2 values were respectively 0.19 and 0.018 microg/ml. One correlation between both methods was observed for MICs-24h and MICs-2s (p<.05). However, there was no significant difference according to origin of isolates (p<.05). CONCLUSIONS: 1. This study assessed the potent role of posaconazole against A. fumigatus isolates with very low MICs. 2. MIC values were not predictive of pathogenicity. 3. E-test method by reading after 24h-incubation time could easily replace the time-consuming NCCLS M38-P reference method. [less ▲] Detailed reference viewed: 17 (0 ULg) In vitro tests for evaluation of the hatchability of the eggs of Psoroptes mites following exposure to acaricidal compoundsLekimme, Mireille ; Mignon, Bernard ; Leclipteux, Thierry et alin Medical and Veterinary Entomology (2006), 20(1), 102-105 Three in vitro assays for the evaluation of the hatchability of the eggs of the mite Psoroptes ovis (Hering) (Acari: Psoroptidae) are described. Preliminary trials showed that hatching occurs at very high ... [more ▼] Three in vitro assays for the evaluation of the hatchability of the eggs of the mite Psoroptes ovis (Hering) (Acari: Psoroptidae) are described. Preliminary trials showed that hatching occurs at very high rates when eggs are incubated under conditions of high humidity, on a liquid medium and in agarose dishes. These three protocols were compared, taking into account the ease of preparation, follow-up and accuracy of counting. The best protocol was found to be the use of agarose dishes. It was accurate, easy to carry out and reproducible for further evaluation of existing or potentially new compounds against both adults and eggs of Psoroptes spp. The acaricidal properties of phoxim and amitraz were then evaluated against eggs and adults using the three protocols. Results showed that for both drugs, in vitro adulticidal activity was complete, whereas the in vitro ovicidal activity was only partial. Nevertheless, efficacy of amitraz against both adults and eggs was shown to be higher than that of phoxim. [less ▲] Detailed reference viewed: 44 (3 ULg) In vitro tests for evaluation of the hatchability of the eggs of Psoroptes mites following exposure to acaricidal compounds.Lekimme, Mireille ; Mignon, Bernard ; et alin Medical and Veterinary Entomology (2006), 20(1), 102-105 Three in vitro assays for the evaluation of the hatchability of the eggs of the mite Psoroptes ovis (Hering) (Acari: Psoroptidae) are described. Preliminary trials showed that hatching occurs at very high ... [more ▼] Three in vitro assays for the evaluation of the hatchability of the eggs of the mite Psoroptes ovis (Hering) (Acari: Psoroptidae) are described. Preliminary trials showed that hatching occurs at very high rates when eggs are incubated under conditions of high humidity, on a liquid medium and in agarose dishes. These three protocols were compared, taking into account the ease of preparation, follow-up and accuracy of counting. The best protocol was found to be the use of agarose dishes. It was accurate, easy to carry out and reproducible for further evaluation of existing or potentially new compounds against both adults and eggs of Psoroptes spp. The acaricidal properties of phoxim and amitraz were then evaluated against eggs and adults using the three protocols. Results showed that for both drugs, in vitro adulticidal activity was complete, whereas the in vitro ovicidal activity was only partial. Nevertheless, efficacy of amitraz against both adults and eggs was shown to be higher than that of phoxim. [less ▲] Detailed reference viewed: 9 (2 ULg) In vitro titration of Theileria parva tick derived stabilates; ; et al in Parasitology (2004), 128(Part 2), 131-137 Immunization agairist the protozoan Theileria parva by infection and treatment has proved to be very efficient for the Control Of East Coast fever, an acute and often-fatal lymphoproliferative tick-borlic ... [more ▼] Immunization agairist the protozoan Theileria parva by infection and treatment has proved to be very efficient for the Control Of East Coast fever, an acute and often-fatal lymphoproliferative tick-borlic disease of cattle in Eastern, Central and Southern Africa. The immunizing dose of live T. Parva sporozites used in this method is usually determined by in vitro titration. An alternative in vivo method of quantitification of sporozoites ill whole tick-derived stabilites is proposed. The method consists of incubating serially diluted T. Parva stabilities with boville peripheral blood lymphocytes, the host cell that is infected naturally. Allowing the cultures to incubate undisturbed for the full cultivation period (10 days) reduced the variability amoung replicate titrations. fungal contaminations were avoided by centrifuging stabilates at 400 g prior to the incubation, which did not precipiate sporozoites significantly. Fungistics, Nysatin and Flucytosine did not appear to interfere with the in vitro development of 2 stabilates but their effect on fungal growth was limited. In vitro titration data were compared to in vivo infection data for 2. In vivo titration of T. parva sporozoites should allow more ethicl and efficient research on the preparation and storage of T. Parva tick-derived stabilates. [less ▲] Detailed reference viewed: 10 (1 ULg) In vitro transport studies of nifedipine nanoparticles across Caco-2/HT29- 5M21 cultures and co-cultures; ; et al Poster (2006) Detailed reference viewed: 24 (1 ULg) In vitro tuberization of potato.; Anceau, Christine ; Dumont, Josée et alin Internationaal Symposium over Fytofarmacie en Fytiatrie (1986), 38 Detailed reference viewed: 14 (9 ULg) In vitro tubulogenesis of endothelial cells by relaxation of the coupling extracellular matrix-cytoskeleton.Deroanne, Christophe ; ; Nusgens, Betty ![]() in Cardiovascular Research (2001), 49(3), 647-58 OBJECTIVE: This investigation aimed at determining the importance of the rigidity of the adhesive support and the participation of the cytoskeleton in tubulogenesis of endothelial cells in vitro. METHODS ... [more ▼] OBJECTIVE: This investigation aimed at determining the importance of the rigidity of the adhesive support and the participation of the cytoskeleton in tubulogenesis of endothelial cells in vitro. METHODS: The morphotype, biosynthetic phenotype and cytoskeleton organization of human umbilical vein endothelial cells (HUVEC) were analyzed on supports of variable mechanical resistance. RESULTS: Western blot analysis revealed a strong reduction of the expression of actin and focal-adhesion plaque (FAP) proteins in HUVEC organized in tube-like structures (TLS) on soft matrigel or on matrigel co-polymerized with heat-denatured collagen as compared to HUVEC remaining in a monolayer pattern on rigid matrigel-coat or on matrigel co-polymerized with type I collagen. Human skin fibroblasts morphotype was not altered in these culture conditions and the pattern of FAP proteins and actin was not modulated. By using polyacrylamide gels polymerized with various concentrations of bis-acrylamide to modulate the mechanical resistance of the support and cross-linked to a constant amount of gelatin to provide an equal density of attachment sites, it was shown that the less rigid the support, the more endothelial cells switched to a tube-like pattern. Collagen type I-induced tubulogenesis was accompanied by a profound and reversible remodeling of the actin-FAP complex suggesting a weakening of the bridging between extracellular matrix (ECM) and the cytoskeleton. Human skin fibroblasts and smooth muscle cells, used as control cells, adhered strongly to the collagen, did not form TLS and their network of actin stress fibers was not remodeled. The inhibition of collagen type I-induced tubulogenesis by agents altering the actin cytoskeleton-FAP complex including calpain type I inhibitor, orthovanadate, KT5720 and jasplakinolide, further supports the determinant role of mechanical coupling between the cells and the matrix in tubulogenesis. CONCLUSIONS: A reduced tension between the endothelial cells and the extracellular matrix, originating in the support or within the cells is sufficient to trigger an intracellular signaling cascade leading to tubulogenesis, an event mimicking one of the last steps of angiogenesis. [less ▲] Detailed reference viewed: 13 (2 ULg) An in vitro whole blood model to test the effects of different stimuli conditions on the release of myeloperoxidase and elastase by equine neutrophils.Ceusters, Justine ; Serteyn, Didier ; MINGUET, Grégory et alin Veterinary Immunology and Immunopathology (2012), 150(3-4), 221-7 Horses are particularly sensitive and exposed to excessive inflammatory responses evolving toward an important stimulation of polymorphonuclear neutrophils (PMNs). The aim of this work was to stimulate ... [more ▼] Horses are particularly sensitive and exposed to excessive inflammatory responses evolving toward an important stimulation of polymorphonuclear neutrophils (PMNs). The aim of this work was to stimulate equine neutrophils in whole blood and to evaluate their response by measuring the release of total and active myeloperoxidase (MPO) and total elastase, considered as markers of neutrophil stimulation and degranulation. Because of the critical importance of the concomitant presence of LPS and TNF-alpha in equine pathological situations, we combined these two natural mediators to stimulate PMN and compared the response with those obtained after the PMN stimulation with each mediator used alone and well-known artificial stimulation systems such as 12-phorbol 13-myristate acetate (PMA) and the combination of cytochalasin B (CB) and N-formyl-methionyl-leucyl-phenylalanine (fMLP). All the activation systems, PMA, CB/fMLP, TNF-alpha, LPS and LPS/TNF-alpha, induced a significant release of total MPO in whole blood but only the combinations CB/fMLP and LPS/TNF-alpha significantly favored the release of active MPO. Regarding the total elastase, we did not observe a significant release in all the stimulated conditions except with PMA. It appears clearly that the choice of the neutrophil stimulation model is fundamental for the selection of potentially active pharmacological agents, especially on MPO activity. [less ▲] Detailed reference viewed: 17 (8 ULg) In vitro-generated interspecific recombinants between bovine herpesviruses 1 and 5 show attenuated replication characteristics and establish latency in the natural host; ; et al in BMC Veterinary Research (2011), 7 Detailed reference viewed: 13 (6 ULg) |
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