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See detailCytokines et choc septique
Lamy, Maurice ULg; Damas, Pierre ULg

in Bulletin de l'Académie Royale de Médecine de Belgique (1991), 146(6-7), 270

Detailed reference viewed: 11 (4 ULg)
See detailCytokines et nouveaux marqueurs inflammatoires
Chapelle, Jean-Paul ULg; Geenen, Vincent ULg; Malaise, Michel ULg et al

Conference (1999, March 13)

Detailed reference viewed: 17 (11 ULg)
See detailCytokines in the feto-maternal relationship
Geenen, Vincent ULg

Conference (1998, September)

Detailed reference viewed: 7 (0 ULg)
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See detailCytokines produced in lymph follicles.
Tsunoda, R.; Cormann, N.; Heinen, Ernst ULg et al

in Immunology Letters (1989), 22(2), 129-34

The events occurring inside lymph follicles during a germinal center reaction are poorly understood. Using B and T lymphoid cell populations prepared from human tonsillar lymph follicles, and enriched or ... [more ▼]

The events occurring inside lymph follicles during a germinal center reaction are poorly understood. Using B and T lymphoid cell populations prepared from human tonsillar lymph follicles, and enriched or not in macrophages or in follicular dendritic cells, we examined the production of cytokines by these cells in vitro. Interleukin 6 (IL-6) and tumor necrosis factor (TNF) were found in the supernatants of cultures stimulated with phytohemagglutinin or pokeweed mitogen. IL-1 beta was occasionally detected; its secretion apparently depends on the origin of the tonsils, the stimulation, and the cell populations. IFN-gamma and IL-2 were not produced in significant amounts by these lymph follicle cells. IL-4 was only found in very low concentrations in the supernatant of the different cell cultures. The cell populations containing follicular dendritic cells produced more IL-6 and TNF than the others, especially than those composed of only B and T cells. [less ▲]

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See detailThe cytokines: a possible role in sepsis
Damas, Pierre ULg

in Current Opinion in Anaesthesiology (1991), 4(2), 241-246

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See detailCytokinin application to the shoot apical meristem of Sinapis alba enhances secondary plasmodesmata formation.
Ormenese, Sandra ULg; Bernier, Georges ULg; Périlleux, Claire ULg

in Planta (2006), 224(6), 1481-4

A single application of cytokinin benzyladenine causes a threefold increase in the frequency of plasmodesmata in the vegetative shoot apical meristem (SAM) of Sinapis alba plants. This increase is ... [more ▼]

A single application of cytokinin benzyladenine causes a threefold increase in the frequency of plasmodesmata in the vegetative shoot apical meristem (SAM) of Sinapis alba plants. This increase is observed 20 h after application within all cell layers (L1, L2, L3) as well as at the interfaces between these layers. Evidence is presented indicating that cytokinin promotes mainly the formation of new secondary plasmodesmata. A similar increase in the frequency of secondary plasmodesmata was observed in the Sinapis SAM during the floral transition induced by a single long day, suggesting that this effect of the long day is mediated by cytokinin. [less ▲]

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See detailCytokinin levels in leaves, leaf exudate and shoot apical meristem of Arabidopsis thaliana during floral transition
Corbesier, Laurent; Prinsen, Els; Jacqmard, Annie ULg et al

in Journal of Experimental Botany (2003), 54(392), 2511-2517

Understanding the complete picture of floral transition is still impaired by the fact that physiological studies mainly concern plant species whose genetics is poorly known, and vice versa. Arabidopsis ... [more ▼]

Understanding the complete picture of floral transition is still impaired by the fact that physiological studies mainly concern plant species whose genetics is poorly known, and vice versa. Arabidopsis thaliana has been successfully used to unravel signalling pathways by genetic and molecular approaches, but analyses are still required to determine the physiological signals involved in the control of floral transition. In this work, the putative role of cytokinins was investigated using vegetative plants of Arabidopsis (Columbia) induced to flower synchronously by a single 22 h long day. Cytokinins were analysed in leaf extracts, leaf phloem exudate and in the shoot apical meristem at different times during floral transition. It was found that, in both the leaf tissues and leaf exudate, isopentenyladenine forms of cytokinins increased from 16 h after the start of the long day. At 30 h, the shoot apical meristem of induced plants contained more isopentenyladenine and zeatin than vegetative controls. These cytokinin increases correlate well with the early events of floral transition. [less ▲]

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See detailCytokinin modulates catalase activity and coumarin accumulation in in vitro cultures of tobacco
Petit-Paly, Geneviève; Franck, Thierry ULg; Brisson, Louise et al

in Journal of Plant Physiology (1999), 155(1), 9-15

Cytokinins (CKs) represent an important class of phytohormones particularly known for their antisenescence properties that might be regulated through an effect on the oxidative metabolism. In the present ... [more ▼]

Cytokinins (CKs) represent an important class of phytohormones particularly known for their antisenescence properties that might be regulated through an effect on the oxidative metabolism. In the present work, we demonstrate the effect of CKs on catalase activity in tobacco cultivated in vitro. The catalase activity observed in suspension-cultured cells decreased slightly during the first hour of CK treatment and increased thereafter to double the level detected in untreated cells. In contrast to these results, catalase activity was inhibited in shoot cultures in which the endogenous levels of CK were elevated by the introduction of the isopentenyltransferase gene or by an exogenous feeding of CK to the cultures. Interestingly, this catalase inhibition correlated with an accumulation of scopolin, an inducible coumarin. Taken together, our results show that CK modulates (directly or undirectly) catalase activity. The inverse relationship that was always found between scopolin accumulation and catalase activity is discussed in terms of vitrification and habituation. [less ▲]

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See detailCytokinin promotes flowering of Arabidopsis via transcriptional activation of the FT paralogue TSF
D'Aloia, Maria ULg; Bonhomme, Delphine ULg; Bouché, Frédéric ULg et al

in Plant Journal (The) (2011), 65

Cytokinins are involved in many aspects of plant growth and development and physiological evidence also indicates that they have a role in floral transition. In order to integrate these phytohormones into ... [more ▼]

Cytokinins are involved in many aspects of plant growth and development and physiological evidence also indicates that they have a role in floral transition. In order to integrate these phytohormones into the current knowledge of genetically defined molecular pathways to flowering, we performed exogenous treatments of adult wild-type and mutant Arabidopsis plants and analysed the expression of candidate genes. We used a hydroponic system that enables synchronous growth and flowering of Arabidopsis and allows precise application of chemicals to the roots for defined periods of time. We show that application of N6-benzylaminopurine (BAP) promotes flowering of plants grown in non-inductive short days. The response to cytokinin treatment does not require FLOWERING LOCUS T (FT) but activates its paralogue TWIN SISTER OF FT (TSF), as well as FD, which encodes a partner protein of TSF, and the downstream gene SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1). Treatment of selected mutants confirmed that TSF and SOC1 are necessary for the flowering response to BAP while the activation cascade might partially act independently of FD. These experiments provide a mechanistic basis for the role of cytokinins in flowering and demonstrate that the redundant genes FT and TSF are differently regulated by distinct floral inducing signals. [less ▲]

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See detailA cytokinin route to flowering in Arabidopsis
Bouché, Frédéric ULg; André, Julie ULg; D'Aloia, Maria ULg et al

Poster (2011, June)

Cytokinins (CKs) are involved in many physiological processes. We observed that the application of N6-benzylaminopurine (BAP) to the roots of hydroponically grown plants of Arabidopsis thaliana promotes ... [more ▼]

Cytokinins (CKs) are involved in many physiological processes. We observed that the application of N6-benzylaminopurine (BAP) to the roots of hydroponically grown plants of Arabidopsis thaliana promotes flowering in non-inductive short days. The response to BAP treatment does no require FLOWERING LOCUS T (FT), but activates its paralogue TWIN SISTER OF FT (TSF), as well as FD and SUPPRESSOR OF OVEREXPRESSION OF CO1 (SOC1) (D'Aloia et al., 2011). We present here complementary data obtained with transgenic plants overexpressing a catalytic CK OXIDASE/DEHYDROGENASE (CKX) in the roots. The high efficiency of BAP in promoting flowering in our experimental system contrasts with the variability that emerges from studies gathered in literature. Many factors, either experimental or inherent to plant material, might explain these discrepancies and we are interested in identifying endogenous regulators that might provide a mechanistic explanation. We are therefore investigating whether the endogenous pathways underlying plant developmental phase changes might regulate the relative contribution of CKs to flowering. [less ▲]

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See detailCytokinins and ethylene stimulate indole alkaloid accumulation in cell suspension cultures of Catharanthus roseus by two distinct mechanisms
Yahia, Abdelouahab; Kevers, Claire ULg; Gaspar, Thomas ULg et al

in Plant Science (1998), 133(1), 9-15

The interactions between cytokinins and ethylene on alkaloid accumulation in a periwinkle cell line have been examined. It was found that (a) either exogenously-applied cytokinins or ethylene (the latter ... [more ▼]

The interactions between cytokinins and ethylene on alkaloid accumulation in a periwinkle cell line have been examined. It was found that (a) either exogenously-applied cytokinins or ethylene (the latter through ethephon degradation) greatly enhanced ajmalicine accumulation in cells subcultured in a 2,4-dichlorophenoxyacetic acid-free medium; (b) the enhancing effect of cytokinin was not mediated by enhancement of endogenous ethylene production contrary to what is found in some plant models, (c) the responses to exogenous cytokinin and ethylene were additive and showed a different pattern of expression. It may be concluded that cytokinin and ethylene can up-regulate the alkaloid production in a periwinkle cells through independent pathways when added exogenously to the cultures. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved. [less ▲]

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See detailCytological and cytochemical analysis of the effects of cis-dichlorodiamino platinum (II) on chick fibroblasts cultivated in vitro.
Heinen, Ernst ULg; Bassleer, R.

in Chemotherapy (1976), 22(3-4), 253-61

Chick embryo fibroblasts cultivated in vitro and treated with cis-dichlorodiamino platinum (II) have been analysed by cytological and cytochemical methods. Morphological alterations (in the nucleoli, in ... [more ▼]

Chick embryo fibroblasts cultivated in vitro and treated with cis-dichlorodiamino platinum (II) have been analysed by cytological and cytochemical methods. Morphological alterations (in the nucleoli, in the chromatin and in the cytoplasm), inhibition of DNA and RNA syntheses and of cell multiplication have been noted. Under some conditions, cells are blocked just before entering into mitosis (G2 block) and can become polyploid. A high degree of cell degeneration has also been observed. [less ▲]

Detailed reference viewed: 25 (11 ULg)
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See detailCytological and ecological complexity in the Early Mesoproterozoic.
Javaux, Emmanuelle ULg; Knoll, A. H.; Walter, M.

Conference (2001, November)

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See detailCytological Comparison of Leaves and Stems of Prunus Avium L. Shoots Cultured on a Solid Medium with Agar or Gelrite
Franck, Thierry ULg; Crevecoeur, Michelle; Wuest, J. et al

in Biotechnic & Histochemistry : Official Publication of the Biological Stain Commission (1998), 73(1), 32-43

An axillary proliferating clone of Prunus avium L. was subcultured every four weeks on solid MS medium with agar as the gelling agent. Vitrification (hyperhydricity) of shoots was induced in one four week ... [more ▼]

An axillary proliferating clone of Prunus avium L. was subcultured every four weeks on solid MS medium with agar as the gelling agent. Vitrification (hyperhydricity) of shoots was induced in one four week cycle with the same medium except that agar was replaced by gelrite. During culture on the vitrifying medium, the water content of the shoots progressively increased with a parallel decrease in chlorophyll content. Cytological differences between the leaves and stems of the vitrified and normal shoots were detected by light and electron (both transmission and scanning) microscopy. Leaves of vitrified shoots were characterized by lower number of chloroplasts in the palisade parenchyma and by a defective cuticle. The stems of vitrified shoots had a less developed and lignifled xylem tissue, lacked sclerenchymatic areas and showed hypertrophy of the cortical parenchyma. More intense vacuolar activity with evaginations of the chloroplast envelope into the vacuole was noted in cells of vitrified leaves. [less ▲]

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See detailCytological diagnosis of endometritis in the mare: a comparative study
Daspet, Sarah-Morgane; Ponthier, Jérôme ULg; Jolly, Sandra ULg et al

in Reproduction in Domestic Animals (2010, September), 45s3

It was concluded that the brush swab was a promising diagnostic tool for use in field conditions.

Detailed reference viewed: 143 (16 ULg)
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See detailCytological effects of culture media conditioned B16 melanoma cells and 3T3 fibroblasts
Coucke, Paul; Siwek, B.; De Pauw-Gillet, Marie-Claire ULg et al

in Anticancer Research (1991), 11(2), 801-804

Cytotoxic soluble fractions (M.W.<1,000) were prepared from media conditioned by mixed cultures of 3T3 fibroblasts and B16 cells. The ultrastructural analyses of cells (B16 or 3T3) treated with these ... [more ▼]

Cytotoxic soluble fractions (M.W.<1,000) were prepared from media conditioned by mixed cultures of 3T3 fibroblasts and B16 cells. The ultrastructural analyses of cells (B16 or 3T3) treated with these fractions revealed in them mitochondria swelling, blebs, broken membranes and dead cells. [less ▲]

Detailed reference viewed: 29 (3 ULg)
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See detailCytology of reactional spleen may be misleading
Ramery, Eve ULg; Vangrinsven, Emilie ULg; Gommeren, Kris ULg et al

Poster (2016, October)

Detailed reference viewed: 9 (1 ULg)
See detailLa cytolyse des leucocytes caprins induite par la leucotoxine de Mannheimia haemolytica est mediée par la sous-unité CD18 des bêta2-intégrines
Fett, Thomas ULg; Zecchinon, Laurent; Vanden bergh, Philippe et al

Conference (2008, September 23)

La mannheimiose est la maladie respiratoire prédominante parmi les ruminants alors qu’elle n’affecte pas les autres mammifères. Cette spécificité d’espèces trouve son origine dans l’interaction tout aussi ... [more ▼]

La mannheimiose est la maladie respiratoire prédominante parmi les ruminants alors qu’elle n’affecte pas les autres mammifères. Cette spécificité d’espèces trouve son origine dans l’interaction tout aussi spécifique entre la leucotoxine (LktA) de Mannheimia haemolytica et la sous-unité CD18 du récepteur LFA-1 des bêtes bovine et ovine. Nous avons ainsi postulé que la LktA utilisait également le CD18 comme récepteur sur les leucocytes caprins. Pour démontrer cette hypothèse, nous avons transfecté la lignée lymphoblastique K-562, naturellement déficiente en bêta2-intégrines, avec les ADNcs encodant les CD11a et CD18 caprins afin de déterminer la susceptibilité des transfectants à la cytolyse induite par la LktA. Une analyse par cytométrie en flux a révélé l’expression en surface du LFA-1 caprin et la lyse par la LktA de manière dose-dépendante alors que la lignée parentale restait insensible. Par ailleurs, les cellules K-562 exprimant le CD18 caprin et le CD11a humain ou bovin sont également sensibles à la LktA alors que les K-562 exprimant le CD11a caprin et le CD18 humain ne le sont pas. Pris dans leur ensemble, ces résultats indiquent que le CD18 des leucocytes caprins sert de récepteur à la LktA de Mannheimia haemolytica. [less ▲]

Detailed reference viewed: 36 (0 ULg)