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See detailEffects of lesions of nucleus taeniae on appetitive and consummatory aspects of male sexual behavior in Japanese quail
Absil, Philippe ULg; Braquenier, Jean-Baptiste ULg; Balthazart, Jacques ULg et al

in Brain, Behavior & Evolution (2002), 60(1), 13-35

Neurochemical, hodological and functional criteria suggest that the nucleus taeniae and parts of the adjacent archistriatum represent the avian homologue of parts of the mammalian amygdaloid complex. It ... [more ▼]

Neurochemical, hodological and functional criteria suggest that the nucleus taeniae and parts of the adjacent archistriatum represent the avian homologue of parts of the mammalian amygdaloid complex. It has been proposed in particular that the nucleus taeniae is the homologue of the mammalian medial amygdala. In male quail, relatively large lesions to the posterior/medial archistriatum selectively decrease the expression of appetitive sexual behavior in a manner reminiscent of similar manipulations involving the medial amygdala in mammals. We investigated the effects of discrete lesions restricted to nucleus taeniae and of lesions to an adjacent part of the archistriaturn (pars intermedium ventralis, Alv) on the expression of appetitive (ASB) and consummatory (CSB) aspects of male sexual behavior. ASB was measured by a learned social proximity response (after copulation a male quail stands in front of a window providing visual access to a female) and by the frequency of rhythmic cloacal sphincter movements. CSB was assessed by the frequency of mount attempts (MA) and cloacal contact movements (CCM). Lesions confined to nucleus taeniae and to Alv did not influence the acquisition or the maintenance of the two responses indicative of ASB. In contrast, lesions of nucleus taeniae significantly increased the occurrence frequencies of MA and CCM when administered before the beginning of behavior testing and increased the frequency of MA only when performed on sexually experienced subjects. No effect of Alv lesions could be detected. The discrepancy between these results and previous experiments in quail might reflect procedural differences, but more probably differences in locations of the lesions that were restricted in the current study to the anterior part of taeniae. Those in the Thompson study were in the posterior part of this nucleus. These findings indicate that there is a larger degree of functional heterogeneity in the nucleus taeniae than previously thought. The effects of taeniae lesions suggest that this nucleus, similar to the medial amygdala in mammals, might be implicated in the control of sexual satiety. Copyright (C) 2002 S. Karger AG, Basel. [less ▲]

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See detailEffects of lesions of the medial preoptic nucleus on the testosterone-induced metabolic changes in specific brain areas in male quail
Balthazart, Jacques ULg; Stamatakis, A.; Bacola, S. et al

in Neuroscience (2001), 108(3), 447-466

The effects of bilateral lesions of the medial preoptic nucleus in association with testosterone on the metabolic activity in discrete brain regions was studied quantitatively by the in vivo ... [more ▼]

The effects of bilateral lesions of the medial preoptic nucleus in association with testosterone on the metabolic activity in discrete brain regions was studied quantitatively by the in vivo autoradiographic 2-deoxyglucose method. Adult male quail were castrated and then left without hormone replacement therapy or treated with testosterone or treated with testosterone and submitted to a bilateral lesion of the medial preoptic nucleus, a brain region that plays a key role in the activation of male copulatory behavior by testosterone. Treatment for about 10 days with testosterone activated the expression of the full range of male sexual behaviors and these behaviors were completely suppressed by the medial preoptic nucleus lesions. Mapping of 2-deoxyglucose uptake revealed both increases and decreases of metabolic activity in discrete brain regions associated with the systemic treatment with testosterone as well as with the lesion of the medial preoptic nucleus. Testosterone affected the oxidative metabolism in brain areas that are known to contain sex steroid receptors (such as the nucleus taeniae and the paraventricular and ventromedial nuclei of the hypothalamus) but also in nuclei that are believed to be devoid of such receptors. Effects of testosterone in these nuclei may be indirect or reflect changes in terminals of axons originating in steroid-sensitive areas. Bilateral medial preoptic nucleus lesions affected 2-deoxyglucose uptake in a variety of brain regions. Some of these regions are known to be mono-synaptically connected to the medial preoptic nucleus. Metabolic depression in these areas may reflect retrograde changes in the neurons projecting to the damaged field. The metabolic changes identified in the present study confirm the prominent role of the preoptic area in the control of sexual behavior, show that changes in the physiology of the visual system represent one of the ways through which testosterone influences the occurrence of this behavior and demonstrate that the medial preoptic nucleus has marked effects on the metabolic activity in a variety of limbic and telencephalic structures. This study also indicates that the medial preoptic nucleus affects the activity of the area ventralis of Tsai, a dopaminergic area known to send projections to a variety of hypothalamic, thalamic and mesencephalic nuclei that are implicated in the control of male sexual behavior. These data therefore support the notion that the control of the dopaminergic activity in the area ventralis of Tsai by the medial preoptic nucleus represents one of the ways through which the medial preoptic area regulates male reproductive behavior. (C) 2001 IBRO. Published by Elsevier Science Ltd. All rights reserved. [less ▲]

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See detailEffects of level of intake and of available volatile fatty acids on the absorptive capacity of sheep rumen
Doreau, Michel; Ferchal, Edwin; Beckers, Yves ULg

in Small Ruminant Research (1997), 25

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See detailEffects of light deprivation on visual evoked potentials in migraine without aura.
Coppola, Gianluca; Cremers, Julien ULg; GERARD, Pascale ULg et al

in BMC Neurology (2011), 11

BACKGROUND: The mechanisms underlying the interictal habituation deficit of cortical visual evoked potentials (VEP) in migraine are not well understood. Abnormal long-term functional plasticity of the ... [more ▼]

BACKGROUND: The mechanisms underlying the interictal habituation deficit of cortical visual evoked potentials (VEP) in migraine are not well understood. Abnormal long-term functional plasticity of the visual cortex may play a role and it can be assessed experimentally by light deprivation (LD). METHODS: We have compared the effects of LD on VEP in migraine patients without aura between attacks (MO, n = 17) and in healthy volunteers (HV, n = 17). Six sequential blocks of 100 averaged VEP at 3.1 Hz were recorded before and after 1 hour of LD. We measured VEP P100 amplitude of the 1st block of 100 sweeps and its change over 5 sequential blocks of 100 responses. RESULTS: In HV, the consequence of LD was a reduction of 1st block VEP amplitude and of the normal habituation pattern. By contrast, in MO patients, the interictal habituation deficit was not significantly modified, although 1st block VEP amplitude, already lower than in HV before LD, further decreased after LD. CONCLUSIONS: Light deprivation is thought to decrease both excitatory and subsequent inhibitory processes in visual cortex, which is in line with our findings in healthy volunteers. The VEP results in migraine patients suggest that early excitation was adequately suppressed, but not the inhibitory mechanisms occurring during long term stimulation and habituation. Accordingly, deficient intracortical inhibition is unlikely to be a primary factor in migraine pathophysiology and the habituation deficit. [less ▲]

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See detailEffects of light on cerebral activity
Vandewalle, Gilles ULg; Dijk, Derk-Jan; Phillips, Christophe ULg et al

Poster (2008)

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See detailEffects of light on cognitive brain responses depend on circadian phase and sleep homeostasis.
Vandewalle, Gilles ULg; Archer, Simon N; Wuillaume, Catherine et al

in Journal of biological rhythms (2011), 26(3), 249-59

Light is a powerful modulator of cognition through its long-term effects on circadian rhythmicity and direct effects on brain function as identified by neuroimaging. How the direct impact of light on ... [more ▼]

Light is a powerful modulator of cognition through its long-term effects on circadian rhythmicity and direct effects on brain function as identified by neuroimaging. How the direct impact of light on brain function varies with wavelength of light, circadian phase, and sleep homeostasis, and how this differs between individuals, is a largely unexplored area. Using functional MRI, we compared the effects of 1 minute of low-intensity blue (473 nm) and green light (527 nm) exposures on brain responses to an auditory working memory task while varying circadian phase and status of the sleep homeostat. Data were collected in 27 subjects genotyped for the PER3 VNTR (12 PER3(5/5) and 15 PER3(4/4) ) in whom it was previously shown that the brain responses to this task, when conducted in darkness, depend on circadian phase, sleep homeostasis, and genotype. In the morning after sleep, blue light, relative to green light, increased brain responses primarily in the ventrolateral and dorsolateral prefrontal cortex and in the intraparietal sulcus, but only in PER3(4/4) individuals. By contrast, in the morning after sleep loss, blue light increased brain responses in a left thalamofrontoparietal circuit to a larger extent than green light, and only so in PER3(5/5) individuals. In the evening wake maintenance zone following a normal waking day, no differential effect of 1 minute of blue versus green light was observed in either genotype. Comparison of the current results with the findings observed in darkness indicates that light acts as an activating agent particularly under those circumstances in which and in those individuals in whom brain function is jeopardized by an adverse circadian phase and high homeostatic sleep pressure. [less ▲]

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See detailEffects of limestone fillers on surface free energy and electrical conductivity of the interstitial solution of cement mixes
Courard, Luc ULg; Michel, Frédéric ULg; Perkowicz, Sylwia et al

in Cement and Concrete Composites (2014), 45

Most of concrete formulations actually contain mineral additives that are used as an inert filler or supplementary cementitious material (as type II addition). These materials are generally used in order ... [more ▼]

Most of concrete formulations actually contain mineral additives that are used as an inert filler or supplementary cementitious material (as type II addition). These materials are generally used in order to increase concrete performances both in its fresh and hardened states. The mineral additives usually improve the consistency and workability of fresh concrete and reduce the water demand for a required concrete slump because of an additional volume of fines. The way of action depends on the physical and chemical characteristics of fillers. The study of surface free energies and electric conductivities of interstitial solutions of cement mixes modified by blast furnace slags and limestone fillers contributes to a better knowledge of hardening and interaction process. [less ▲]

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See detailEffects of liming on forest soil algal communities
Kostinov, I.; Carnol, Monique ULg; Dulière, J.-F. et al

in Algological Studies (2001), 102

The effects of the application of dolomite lime (5 t ha-1) on soil algal communities were investigated in sessile oak (Quercus petraea (MATT.) LIEB.) and Norway spruce (Picea abies (L.) KARST.) plots ... [more ▼]

The effects of the application of dolomite lime (5 t ha-1) on soil algal communities were investigated in sessile oak (Quercus petraea (MATT.) LIEB.) and Norway spruce (Picea abies (L.) KARST.) plots situated in the Belgian Ardenne. Chlorophyta (60 taxa) were by far the most diverse group, followed by Xanthophyceae (10 taxa), Bacillariophyceae (3 taxa), Cyanophyceae (2 taxa) and Euglenophyceae (1 taxon). In both forest types, liming lead to a significant increase in soil pH, exchangeable magnesium and calcium. In the limed Quercus plots available phosphorus and soil solution nitrate concentrations were also increased. The soil algal diversity was similar in oak and spruce control plots and in limed spruce plots. However, in the limed oak plots a significantly higher algal diversity was observed. On the basis of a CCA analysis, three clusters of plots could be distinguished: a) Picea control plots, b) limed Picea and control Quercus plots, c) limed Quercus plots. Both soil pH and nutrient availability seem to be important in determining algal species composition in these forest soils. [less ▲]

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See detailEffects of lipopeptidesonmodel membranes
Deleu, Magali ULg

in 6th annual surface and colloid symposium: lipid-peptide interactions and biological function (2006)

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See detailEffects of localized fires on concrete slabs
Franssen, Jean-Marc ULg; Dotreppe, Jean-Claude ULg

in Toutlemonde, F. (Ed.) Proceedings of CONSEC'07 (2007)

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See detailEffects of long term soil organic matter restitution mode on soil heterotrophic respiration and soil biological properties.
Buysse, Pauline ULg; Carnol, Monique ULg; Malchair, Sandrine ULg et al

Conference (2011, May 12)

For more than 50 years, an agricultural site divided in several plots is submitted to different organic matter restitution mode to the soil (crop residues, manure,...). The objectives of this study were ... [more ▼]

For more than 50 years, an agricultural site divided in several plots is submitted to different organic matter restitution mode to the soil (crop residues, manure,...). The objectives of this study were to determine (1) whether these different treatments may cause differences between treatments in terms of soil heterotrophic respiration, that would be of the same order of magnitude than differences in total soil organic carbon, (2) how temperature and soil moisture content affect soil heterotrophic respiration in the different treatments, and (3) how different soil biological properties (microbial biomass, metabolic diversity, labile carbon content) are affected in the different treatments. The results from a first measurement campaign carried out in 2010 are presented, together with the remaining questions at this stage of the study. [less ▲]

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See detailEffects of long term soil organic matter restitution mode on soil heterotrophic respiration and soil biological properties.
Buysse, Pauline ULg; Carnol, Monique ULg; Malchair, Sandrine ULg et al

Poster (2011, July)

Soil heterotrophic respiration (SHR) is the process by which CO2 is released during organic matter decomposition. It is generally expected that SHR can act as a positive feedback to global warming ... [more ▼]

Soil heterotrophic respiration (SHR) is the process by which CO2 is released during organic matter decomposition. It is generally expected that SHR can act as a positive feedback to global warming, therefore leading to more CO2 release into the atmosphere. It is thus important to better understand this process. Particularly, agricultural soils may behave as important CO2 sources that are strongly influenced by soil and crop management (e.g. organic matter restitution modes, hereafter “OM-RM”). The present study aimed at determining if, after more than 50 years of application of different OM-RM, (1) significant differences of SHR fluxes can be observed between treatments, (2) SHR responses to temperature and soil moisture content can be affected by the OM-RM and (3) the experimental design is suitable to assess potential differences between treatments. The experimental field is situated in Liroux, near Gembloux in Belgium. At that site, a long term experiment with different OM-RM runs from 1959 onwards. For the present study, three contrasted treatments were considered: (1) exportation of all residues after harvest, (2) addition of manure once every three to four years and (3) restitution of residues after harvest. SHR flux measurements were carried out manually on fourteen occasions from 2 April to 30 July 2010, using a dynamic closed chamber system. Temperature and soil moisture content at 5 cm depth were also measured manually. Results showed that after more than 50 years of OM-RM application, no significant differences could be observed between the three treatments in terms of SHR fluxes and SHR responses to temperature or soil moisture, while the soil organic carbon content did vary significantly between them. The sensitivity to temperature was quite low in all treatments, with a mean Q10 value of 1,36. Besides, SHR fluxes were seen to be more responsive to increases in soil water content than to absolute soil moisture content values. Indeed, when soil moisture content increased between two consecutive measurement dates, the ratio of the corresponding SHR fluxes was larger than 1. Particularly dry conditions in 2010 may actually have caused the fluxes to be very low, making the assessment of differences between treatments more difficult. Moreover, soil dryness is likely to be responsible for the SHR flux increases after rain events, as caused by re-solubilization of organic compounds. Also, an important spatial variability was observed, which may have obscured the assessment of potential differences between treatments. Further investigations will consist in performing a new flux measurement campaign in 2011 that will take the spatial variability issue into account, and in monitoring microbial and soil properties in the different treatments, such as microbial biomass, metabolic activity and labile carbon. [less ▲]

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See detailEffects of long-term population fluctuations in a top predator on invertebrate community composition in Alpine ponds
Wissinger, Scott; Whiteman, Howard; Denoël, Mathieu ULg

Conference (2006)

At our remote study site in central Colorado, the population size of tiger salamanders (Ambystoma tigrinum nebulosum) has fluctuated cyclically over the past 20 years from fewer than 100 to over 5000 ... [more ▼]

At our remote study site in central Colorado, the population size of tiger salamanders (Ambystoma tigrinum nebulosum) has fluctuated cyclically over the past 20 years from fewer than 100 to over 5000 individuals. Comparative data between ponds with and without salamanders, and experimental studies suggest that this species is a keystone predator on benthic and planktonic prey communities. Here we present long-term community data that reveal taxon- and habitat-specific correlations in the population size of benthic and planktonic prey with fluctuations in salamander populations. Changes in the abundance of planktonic, but not benthic invertebrates in temporary habitats were correlated with fluctuations in the abundance of salamanders. In permanent ponds, we observed order-of-magnitude changes in benthic biomass that are negatively correlated with salamander abundance. Among the large-bodied and potentially most vulnerable benthic invertebrates (odonates, caddisflies, beetles, water bugs), several species exhibited negatively coupled cycles, but others fluctuated little or out of phase with changes in salamander abundance. The absence of major shifts in benthic community composition in permanent ponds is probably a result of conflicting predation pressures exerted by different year classes of salamanders. Salamander gut samples suggest that ontogenetic shifts in diet might explain why cyclic fluctuations in the abundance of this predator had only minor impacts on benthic community composition despite having major effects on invertebrate biomass. [less ▲]

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See detailEffects of long-term population fluctuations of a top predator on invertebrate communities in subalpine ponds in Colorado
Wissinger, S.; Whiteman, H.; Denoël, Mathieu ULg et al

Conference (2006)

Experimental and comparative data from subalpine ponds with and without tiger salamanders (Ambystoma tigrinum nebulosum) suggest that this species is a keystone predator on benthic and planktonic prey ... [more ▼]

Experimental and comparative data from subalpine ponds with and without tiger salamanders (Ambystoma tigrinum nebulosum) suggest that this species is a keystone predator on benthic and planktonic prey communities. At our study site in central Colorado, the population size of salamanders has fluctuated cyclically over the past 20 years from fewer than 100 to over 5000 individuals. Here we present long-term benthic data that reveal taxon- and habitat-specific correlations with fluctuations in salamander populations. In temporary habitats, benthic biomass changed little during fluctuations in salamander abundance. In permanent ponds, we observed order-of-magnitude changes in benthic biomass that were negatively correlated with salamander abundance. Among the large-bodied and potentially most vulnerable taxa (odonates, caddisflies, beetles, water bugs), several species exhibited negatively coupled cycles, but others fluctuated little or out of phase with changes in salamander abundance. The absence of major shifts in benthic community composition in permanent ponds is probably a result of conflicting predation pressures exerted by different year classes of salamanders. Data on ontogenetic shifts in salamander diet help explain why cyclic fluctuations in the abundance of this predator had only minor impacts on benthic community composition despite having major effects on invertebrate biomass. [less ▲]

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See detailEffects of long-term strontium ranelate treatment on the risk of nonvertebral and vertebral fractures in postmenopausal osteoporosis: Results of a five-year, randomized, placebo-controlled trial.
Reginster, Jean-Yves ULg; Felsenberg, Dieter; Boonen, Steven et al

in Arthritis and Rheumatism (2008), 58(6), 1687-95

OBJECTIVE: This study was undertaken to assess the effect of strontium ranelate on nonvertebral and vertebral fractures in postmenopausal women with osteoporosis in a 5-year, double-blind, placebo ... [more ▼]

OBJECTIVE: This study was undertaken to assess the effect of strontium ranelate on nonvertebral and vertebral fractures in postmenopausal women with osteoporosis in a 5-year, double-blind, placebo-controlled trial. METHODS: A total of 5,091 postmenopausal women with osteoporosis were randomized to receive either strontium ranelate at 2 gm/day or placebo for 5 years. The main efficacy criterion was the incidence of nonvertebral fractures. In addition, incidence of hip fractures was assessed, by post hoc analysis, in the subset of 1,128 patients who were at high risk of fractures (age 74 years or older with lumbar spine and femoral neck bone mineral density T scores -2.4 or less). The incidence of new vertebral fractures was assessed, using the semiquantitative method described by Genant, in the 3,646 patients in whom spinal radiography (a nonmandatory procedure) was performed during the course of the study. Fracture data were analyzed using the Kaplan-Meier survival method. RESULTS: Of the 5,091 patients, 2,714 (53%) completed the study up to 5 years. The risk of nonvertebral fracture was reduced by 15% in the strontium ranelate group compared with the placebo group (relative risk 0.85 [95% confidence interval 0.73-0.99]). The risk of hip fracture was decreased by 43% (relative risk 0.57 [95% confidence interval 0.33-0.97]), and the risk of vertebral fracture was decreased by 24% (relative risk 0.76 [95% CI 0.65-0.88]) in the strontium ranelate group. After 5 years, the safety profile of strontium ranelate remained unchanged compared with the 3-year findings. CONCLUSION: Our findings indicate that treatment of postmenopausal osteoporosis with strontium ranelate results in a sustained reduction in the incidence of osteoporotic nonvertebral fractures, including hip fractures, and vertebral fractures over 5 years. [less ▲]

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See detailEffects of long-term strontium ranelate treatment on vertebral fracture risk in postmenopausal women with osteoporosis.
Meunier, Pierre; Roux, C.; Ortolani, S. et al

in Osteoporosis International (2009), 20

Vertebral fractures are a major adverse consequence of osteoporosis. In a large placebo-controlled trial in postmenopausal women with osteoporosis, strontium ranelate reduced vertebral fracture risk by 33 ... [more ▼]

Vertebral fractures are a major adverse consequence of osteoporosis. In a large placebo-controlled trial in postmenopausal women with osteoporosis, strontium ranelate reduced vertebral fracture risk by 33% over 4 years, confirming the role of strontium ranelate as an effective long-term treatment in osteoporosis. INTRODUCTION: Osteoporotic vertebral fractures are associated with increased mortality, morbidity, and loss of quality-of-life (QoL). Strontium ranelate (2 g/day) was shown to prevent bone loss, increase bone strength, and reduce vertebral and peripheral fractures. The preplanned aim of this study was to evaluate long-term efficacy and safety of strontium ranelate. METHODS: A total of 1,649 postmenopausal osteoporotic women were randomized to strontium ranelate or placebo for 4 years, followed by a 1-year treatment-switch period for half of the patients. Primary efficacy criterion was incidence of patients with new vertebral fractures over 4 years. Lumbar bone mineral density (BMD) and QoL were also evaluated. RESULTS: Over 4 years, risk of vertebral fracture was reduced by 33% with strontium ranelate (risk reduction = 0.67, p < 0.001). Among patients with two or more prevalent vertebral fractures, risk reduction was 36% (p < 0.001). QoL, assessed by the QUALIOST(R), was significantly better (p = 0.025), and patients without back pain were greater (p = 0.005) with strontium ranelate than placebo over 4 years. Lumbar BMD increased over 5 years in patients who continued with strontium ranelate, while it decreased in patients who switched to placebo. Emergent adverse events were similar between groups. CONCLUSION: In this 4- and 5-year study, strontium ranelate is an effective and safe treatment for long-term treatment of osteoporosis in postmenopausal women. [less ▲]

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See detailEffects of low dose endosulfan exposure on brain neurotransmitter levels in the African clawed frog Xenopus laevis
Preud'Homme, Valérie; Milla, Sylvain; Gillardin, Virginie et al

in Chemosphere (2015), 120(2), 357-364

Understanding the impact of pesticides in amphibians is of growing concern to assess the causes of their decline. Among pesticides, endosulfan belongs to one of the potential sources of danger because of ... [more ▼]

Understanding the impact of pesticides in amphibians is of growing concern to assess the causes of their decline. Among pesticides, endosulfan belongs to one of the potential sources of danger because of its wide use and known effects, particularly neurotoxic, on a variety of organisms. However, the effect of endosulfan was not yet evaluated on amphibians at levels encompassing simultaneously brain neurotransmitters and behavioural endpoints. In this context, tadpoles of the African clawed frog Xenopus laevis were submitted to four treatments during 27 d: one control, one ethanol control, and two low environmental concentrations of endosulfan (0.1 and 1 μg L−1). Endosulfan induced a significant increase of brain serotonin level at both concentrations and a significant increase of brain dopamine and GABA levels at the lower exposure but acetylcholinesterase activity was not modified by the treatment. The gene coding for the GABA transporter 1 was up-regulated in endosulfan contaminated tadpoles while the expression of other genes coding for the neurotransmitter receptors or for the enzymes involved in their metabolic pathways was not significantly modified by endosulfan exposure. Endosulfan also affected foraging, and locomotion in links with the results of the physiological assays, but no effects were seen on growth. These results show that low environmental concentrations of endosulfan can induce adverse responses in X. laevis tadpoles. At a broader perspective, this suggests that more research using and linking multiple markers should be used to understand the complex mode of action of pollutants. [less ▲]

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See detailEffects of Macrophage Transplantation in the Injured Adult Rat Spinal Cord: A Combined Immunocytochemical and Biochemical Study
Franzen, Rachelle ULg; Schoenen, Jean ULg; Leprince, Pierre ULg et al

in Journal of Neuroscience Research (1998), 51(3), 316-27

Early and robust invasion by macrophages may be one of the reasons why axonal regeneration is more effective in the PNS than in the CNS. Therefore, we have grafted autologous peritoneal macrophages ... [more ▼]

Early and robust invasion by macrophages may be one of the reasons why axonal regeneration is more effective in the PNS than in the CNS. Therefore, we have grafted autologous peritoneal macrophages labeled with fluorescent latex microspheres into spinal cord compression lesions. At various survival times, we have studied their effect on the expression of neuronal (neurofilaments [NF], calcitonin gene-related peptide [CGRP], 5-hydroxytryptamine [5-HT]) and nonneuronal markers (myelin-associated glycoprotein [MAG], glial fibrillary acidic protein [GFAP], laminin) by using semiquantitative Western blot and immunohistochemical techniques. After 1 month, we observed a significant decrease of the expression of MAG as well as an important invasion of the lesion site by neurites, chiefly peptidergic axons of presumed dorsal root origin, in macrophage-grafted animals compared with controls. In addition, angiogenesis and Schwann cell infiltration were more pronounced after macrophage grafts, providing an increase in laminin, a favorable substrate for axonal regrowth. By using reverse transcription-polymerase chain reaction (RT-PCR), mRNAs for tumor necrosis factor-alpha (TNF-alpha) were detected in the transplanted cells, whereas results were negative for nerve growth factor (NGF), neurotrophin-3 (NT-3), brain-derived neurotrophic factor (BDNF), or acidic fibroblast growth factor (aFGF) and basic fibroblast growth factor (bFGF). Thus, macrophage grafts may represent an interesting strategy to promote axonal regeneration in the CNS. Our study suggests that they may exert their beneficial effects by degrading myelin products, which inhibit axonal regrowth, and by promoting a permissive extracellular matrix containing notably laminin. No evidence for a direct synthesis of neurotrophic factors by the transplanted macrophages was found in this study, but resident glial cells could secrete such factors as a result of stimulation by macrophage-released cytokines. [less ▲]

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