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See detailChanges In Oxylipin Synthesis After Phytophthora Infestans Infection Of Potato Leaves Do Not Correlate With Resistance
Fauconnier, Marie-Laure ULg; Rojas-Beltran, J.; Dupuis, B. et al

in Plant Physiology and Biochemistry (2008), 46(8-9), 823-831

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See detailChanges in peroxidase activity, and level of phenolic compounds during light-induced plantlet regeneration from Eucalyptus camaldulensis Dehn. nodes in vitro
Arezki, Ouoimare; Boxus, Philippe; Kevers, Claire ULg et al

in Plant Growth Regulation (2001), 33(3), 215-219

Node cultures of Eucalyptus camaldulensis Dehn in Petri dishes in vitro under darkness in the presence of an auxin developed meristematic agglomerates (4 to 6 diameter), i.e. dense shoot clusters in which ... [more ▼]

Node cultures of Eucalyptus camaldulensis Dehn in Petri dishes in vitro under darkness in the presence of an auxin developed meristematic agglomerates (4 to 6 diameter), i.e. dense shoot clusters in which outgrowth of numerous successive buds is limited. Similar cultures under a 16 photoperiod produced small green plantlets with reduced leaves often presenting white hypertrophied lenticels and very short roots crowning the stem bases. The use of half-litre glass vials under light allowed direct development of well-developed rooted plantlets, either in the presence of the same auxin or in the presence of a cytokinin. Light favoured an increase in phenolic compounds and a reverse variation of peroxidase activity during the culture cycles. These aspects are discussed in terms of a possible regulation of the endogenous auxin level through a light control of peroxidase activity and the level of phenolic compounds. [less ▲]

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See detailChanges in physicochemical and rheological properties of commercial yogurts during storage.
Pop, Carmen; Apostu, Sorin; Rotar, Ancuta M. et al

Conference (2013)

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See detailChanges in pituitary responsiveness to luteinizing hormone-releasing hormone during an annual cycle in the domestic duck, Anas platyrhynchos L.
Balthazart, Jacques ULg; Willems, Jean; Hendricks, Jean Claude

in Journal of Experimental Zoology (The) (1980), 211(1), 113-23

On four occasions during an annual cycle, 5--7 male domestic ducks were injected with two different doses (5 and 20 micrograms) of synthetic luteinizing hormone-releasing hormone (LHRH) to study the ... [more ▼]

On four occasions during an annual cycle, 5--7 male domestic ducks were injected with two different doses (5 and 20 micrograms) of synthetic luteinizing hormone-releasing hormone (LHRH) to study the possible changes in responsiveness of the pituitary. The luteinizing hormone (LH) and the follicle-stimulating hormone (FSH) were measured in the plasma samples collected after these injections. The induced release of LH changes from one period of the year to another, being minimum in March at the height of the reproductive season. The LHRH injection also induces the release of some FSH but only in limited amounts. The changes in pituitary responsiveness to LHRH are negatively correlated to changes in the circulating LH level (it is high when the plasma LH is low and vice versa). This suggests that the hypothalamic synthesis and release of LHRH must also change during the year. [less ▲]

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See detailChanges in plankton dynamics and biodiversity in the oligotrophic Bay of Calvi (Corsica, Northwestern Mediterranean): response to climate change
Goffart, Anne ULg; Hecq, Jean-Henri ULg

Conference (2008)

The development of the winter-spring phytoplankton bloom is investigated in the Bay of Calvi (Corsica, Ligurian Sea, Northwestern Mediterranean) since 1979. A drastic reduction of phytoplankton biomass is ... [more ▼]

The development of the winter-spring phytoplankton bloom is investigated in the Bay of Calvi (Corsica, Ligurian Sea, Northwestern Mediterranean) since 1979. A drastic reduction of phytoplankton biomass is evidenced over the last three decades. Changes in phytoplankton dynamics and biodiversity are discussed in relation to long-term changes in wind stress, NAO conditions and environmental conditions. As a consequence, time-series results enlighten that the entire food web dynamics is affected and that ecosystem resilience is threatened. [less ▲]

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See detailChanges in polyamines, auxins and peroxidase activity during in vitro rooting of Fraxinus angustifolia shoots: an auxin-independent rooting model
Tonon, Giustino; Kevers, Claire ULg; Gaspar, Thomas ULg

in Tree Physiology (2001), 21(10), 655-663

Among shoots of Fraxinus angustifolia Vahl raised in vitro, 76% rooted after culture on root induction medium for 5 days in darkness followed by culture on root expression medium for 15 days in light. The ... [more ▼]

Among shoots of Fraxinus angustifolia Vahl raised in vitro, 76% rooted after culture on root induction medium for 5 days in darkness followed by culture on root expression medium for 15 days in light. The addition of 20.7 muM indole-butyric acid (IBA) to the root induction medium did not significantly increase the rooting percentage (88%). Putrescine, spermidine, cyclohexylamine (CHA) and aminoguanidine (AG) enhanced rooting up to 100% (98.66% for AG), when applied during root induction in the absence of IBA, otherwise these compounds inhibited rooting, as did spermine and difluoromethylornithine (DFMO) + difluoromethylarginine (DFMA). The root induction phase was characterized by a temporary increase in endogenous free indole-acetic acid (IAA) and putrescine concentrations during root induction, whereas the root expression phase was characterized by increased peroxidase activity and low concentrations of polyamines. These changes were specifically associated with the rooting process and did not depend on the presence of exogenous IBA, because application of exogenous IBA enhanced the amount of IAA in the cuttings but did not affect rooting or the pattern of changes in polyamines and peroxidase. The effects of CHA, AG and DFMO + DFMA on endogenous concentrations of auxins and polyamines highlight the close relationship between the effects of IAA and putrescine in root induction and suggest that polyamine catabolism has an important role in root formation and elongation. [less ▲]

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See detailChanges in Progesterone Metabolism in the Chicken Hypothalamus During Induced Egg Laying Stop and Molting
Balthazart, Jacques ULg; Verheyen, G.; Schumacher, M. et al

in General and Comparative Endocrinology (1988), 72(2), 282-95

In the present study, we have established and validated a radioenzyme assay which permits us to quantify progesterone metabolism in the chicken brain. Progesterone metabolism was then studied in five ... [more ▼]

In the present study, we have established and validated a radioenzyme assay which permits us to quantify progesterone metabolism in the chicken brain. Progesterone metabolism was then studied in five brain areas obtained by microdissection from the telencephalon (part of the lobus paraolfactorius immediately rostral to the preoptic area), the preoptic area, and the hypothalamus. Three metabolites of progesterone were produced in large amounts in these brain regions and were quantified in this study: 5 beta-pregnane-3,20-dione (5 beta-DHP) as well as its metabolite 3 alpha-hydroxy-5 beta-pregnane-20-one (5 beta,3 alpha-ol) and 5 alpha-pregnane-3,20-dione (5 alpha-DHP). The unmetabolized progesterone was also recovered and quantified. The 5 beta-reduction of progesterone (production of 5 beta-DHP and 5 beta,3 alpha-ol) was very active but its 5 alpha-reduction (production of 5 alpha-DHP) was almost absent in the lobus paraolfactorius. An opposite pattern of metabolism was found in the preoptic area and the hypothalamus (higher 5 alpha- but lower 5 beta-reductase activity). The changes in progesterone metabolism in these brain areas were then studied in groups of hens submitted to induced egg laying stop and molting. A significant decrease in progesterone 5 alpha-reduction was found in the median hypothalamus of hens during the period of molt. Simultaneously, the experimental procedures induced significant decreases in the production of 5 beta-DHP by the lobus paraolfactorius, anterior, and medial hypothalamus but induced a significant increase in the production of this metabolite in the preoptic area. These changes are likely to be involved in the control of reproductive functions including sexual behavior and secretion of luteinizing hormone-releasing hormone, and a number of possible causal mechanisms are presented. These should now be tested experimentally especially in view of the very limited information which is now available on the biological effects of the metabolites of progesterone. [less ▲]

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See detailChanges in pubertal timing: Past views, Recast issues
Bourguignon, Jean-Pierre ULg; Domine, Françoise; Glowacz, Fabienne ULg et al

in Bourguignon, Jean-Pierre; Carel, Jean-Claude; Christen, Yves (Eds.) Brain Crosstalk in Puberty in Adolescence (2015)

Abstract The aim of this article is to review some common opinions on changes in pubertal timing and shed new light both on the indicators used in assessing pubertal timing and the underlying mechanisms ... [more ▼]

Abstract The aim of this article is to review some common opinions on changes in pubertal timing and shed new light both on the indicators used in assessing pubertal timing and the underlying mechanisms. While emphasis is usually on advancement in timing of female puberty, it appears that timing also changes in males, both towards earliness for the initial pubertal stages and towards lateness for the final stages. Such findings suggest that the environmental influences on pubertal timing are more complex than initially thought. Moreover, self-evaluated pubertal timing versus peers provides information that is not always consistent with observations at physical examination, suggesting that both perspectives should be considered, especially when studying the correlation between pubertal timing and psychosocial aspects. The mechanisms of changes in pubertal timing may involve both central neuroendocrine control and peripheral effects in tissues targeted by gonadal steroids. Though energy availability is certainly a clue to the mechanism of pubertal development, changes in the control of both energy balance and control of reproduction may vary under the influence of common determinants such as endocrine-disrupting chemicals. These effects can take place right before puberty as well as much earlier, during fetal and neonatal life. Finally, environmental factors can interact with genetic factors in determining changes in pubertal timing. Therefore, the variance in pubertal timing is no longer to be considered under the absolutely separate control of environmental and genetic determinants.  [less ▲]

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See detailChanges in pulse pressure, heart rate and the pulse pressure x heart rate product during squatting in Type 1 diabetes according to age.
Philips, Jean-Christophe ULg; Marchand, Monique ULg; Scheen, André ULg

in Diabetic Medicine : A Journal of the British Diabetic Association (2010), 27(7), 753-61

AIMS: We assessed changes in pulse pressure and heart rate during a squatting test, as indirect markers of arterial stiffness and cardiovascular autonomic neuropathy, respectively, according to age and ... [more ▼]

AIMS: We assessed changes in pulse pressure and heart rate during a squatting test, as indirect markers of arterial stiffness and cardiovascular autonomic neuropathy, respectively, according to age and sex in patients with Type 1 diabetes mellitus. METHODS: We evaluated 160 diabetic patients, divided into four groups of 20 men and 20 women according to age (G1, 20-30 years old; G2, 31-40 years old; G3, 41-50 years old; and G4, 51-60 years old), and 160 non-diabetic matched control subjects. Each subject underwent a 3 min posture test (standing-squatting-standing) with continuous measurement of arterial blood pressure and heart rate by a Finapres device. Overall values throughout the test, baseline levels in initial standing position and squatting-induced changes in pulse pressure, heart rate and the pulse pressure x heart rate product were compared between diabetic patients and healthy control subjects. RESULTS: In the standing position, a greater increase in pulse pressure and lower reduction in heart rate with age led to a significantly higher pulse pressure x heart rate product in diabetic patients compared with control subjects. In the squatting position, a more marked pulse pressure increase in the absence of appropriate reduction in heart rate resulted in a greater rise in the pulse pressure x heart rate product in diabetic patients than in healthy subjects. No major differences were noted between the sexes, with the exception of a stronger relationship between pulse pressure and age in the female population with diabetes. Squatting-derived indices of cardiovascular autonomic neuropathy were also noted with increasing age in diabetic patients. CONCLUSIONS: The marked increase in the pulse pressure x heart rate product ('pulsatile stress') according to age, combined with cardiovascular autonomic neuropathy, may contribute to the higher cardiovascular risk of patients with Type 1 diabetes. [less ▲]

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See detailChanges in respiratory mechanics measured by IOS during the first day of life in calves
Uystepruyst, Ch; Reinhold, P.; Coghe, J. et al

in Proceedings: 17th Symposium of the Comparative Respiratory Society (1999)

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See detailChanges in Serum Concentrations of Steroids During Embryonic and Post-Hatching Development of Male and Female Japanese Quail (Coturnix Coturnix Japonica)
Schumacher, M.; Sulon, Joseph ULg; Balthazart, Jacques ULg

in Journal of Endocrinology (1988), 118(1), 127-34

Serum concentrations of testosterone, 5 alpha-dihydrotestosterone, oestradiol and progesterone were measured by radioimmunoassay combined with Celite chromatography in male and female Japanese quail ... [more ▼]

Serum concentrations of testosterone, 5 alpha-dihydrotestosterone, oestradiol and progesterone were measured by radioimmunoassay combined with Celite chromatography in male and female Japanese quail (Coturnix coturnix japonica) during the second half of embryonic life (days 9-17 of incubation) and during the first 5 weeks after hatching. The mean level of each of the four steroids was significantly affected by the age of the birds. An overall effect of sex was detected by analysis of variance only on oestradiol concentrations, with females having higher serum concentrations than males during most of the age range studied. Significant peaks of testosterone and progesterone were also detected around hatching time. These results are consistent with the view that oestradiol is the major hormone implicated in the sexual differentiation of reproductive behaviour in the quail. The relationships between the circulating concentrations of oestradiol during ontogeny and the critical period of differentiation as postulated by currently accepted models is also discussed. [less ▲]

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See detailChanges in Structure and Symptoms in Knee Osteoarthritis and Prediction of Future Knee Replacement Over 8 Years.
Bruyère, Olivier ULg; Cooper, Cyrus; Pavelka, Karel et al

in Calcified Tissue International (2013), 93

The objective of this study was to assess the association between changes in joint space width (JSW, i.e., structure) or Western Ontario and McMaster Universities (WOMAC) score (i.e., symptoms) over 3 ... [more ▼]

The objective of this study was to assess the association between changes in joint space width (JSW, i.e., structure) or Western Ontario and McMaster Universities (WOMAC) score (i.e., symptoms) over 3 years in patients with knee osteoarthritis and the occurrence of knee replacement over 8 years. We followed 133 subjects with primary knee osteoarthritis prospectively for a mean of 8 years. JSW (standard radiography) and symptoms (total WOMAC score) were assessed every year for 3 years. The rate of knee replacement was recorded for the following 5 years. Logistic regressions were performed according to the intention-to-treat principle. After 8 years' follow-up, ten patients (7.5 %) had undergone a knee replacement. The changes in JSW or WOMAC score over 3 years were significantly associated with the occurrence of knee replacement during the following 5 years (p = 0.02 and p = 0.03, respectively). Each 0.1-mm narrowing of JSW over 3 years was associated with a 14 % (95 % CI 3-25 %) increased risk for knee replacement. For every 10 % increase in WOMAC score, the risk for joint replacement was increased by 16 % (95 % CI 1-33 %). When JSW and WOMAC score were included in the same statistical model, they were still significantly associated with risk for knee replacement (p = 0.02 and p = 0.03, respectively), but JSW change was the only variable that remained significant after adjusting for all potential confounders. Our results suggest that changes in symptoms and, more particularly, in structure over 3 years in patients with osteoarthritis reflect a clinically relevant progression of the disease. [less ▲]

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See detailChanges in sub-fossil chironomid assemblages in two Northern Patagonian lake systems associated with the occurrence of historical fires
Arraneda, A.; Jana, P.; Ortega et al

in Journal of Paleolimnology (2013), 50(1), 41-56

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See detailChanges in termites feeding diets for gut micro-organisms selection and further cultivation
Bauwens, Julien ULg; Brasseur, Catherine ULg; Matteotti, Christel ULg et al

Poster (2011, October 02)

Termites gut may overcome important dietary perturbations, initial diversity acting as key point buffering effects on host, although termites possess their own enzymatic system. Some artificial diets ... [more ▼]

Termites gut may overcome important dietary perturbations, initial diversity acting as key point buffering effects on host, although termites possess their own enzymatic system. Some artificial diets permitted a simplification of the lower termites gut symbiotic system, which could be used as first step in symbionts isolation and cultivation. Preliminary assay of cultivation actually gave encouraging results. Proteomic proved to be suitable tool to investigate such a complex system. Nevertheless, for some symbionts very few genes are sequenced, which should lead to more targeted proteomic studies. Protein chromatography will allow to split up the proteome and more accurate analysis. [less ▲]

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See detailChanges in testosterone metabolism by the brain and cloacal gland during sexual maturation in the Japanese quail (Coturnix coturnix japonica).
Balthazart, Jacques ULg; Schumacher, M.

in Journal of Endocrinology (1984), 100(1), 13-8

Testosterone metabolism in the brain and pituitary and cloacal glands of male and female Japanese quail was studied in vitro during sexual maturation (from 1 day to 5 weeks after hatching). The production ... [more ▼]

Testosterone metabolism in the brain and pituitary and cloacal glands of male and female Japanese quail was studied in vitro during sexual maturation (from 1 day to 5 weeks after hatching). The production of 5 alpha-dihydrotestosterone in the hyperstriatum and cloacal gland and that of androstenedione in the cloacal gland of males was highest at 1 day after hatching, which could be related to the peak of plasma androgens previously demonstrated in neonatal quail. 5 beta-Reductase activity was very high in the brain, but not the pituitary or cloacal glands of young chicks and decreased markedly, especially in the hypothalamus, during sexual maturation. As 5 beta-reduced metabolites of testosterone are inactive androgens, it is suggested that the decrease of 5 beta-reductase activity with age corresponds to a potentiation of the effects of testosterone at the level of the brain. [less ▲]

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See detailChanges in the amygdala amino acid microdialysate after conditioning with a cue associated with ethanol
Quertemont, Etienne ULg; De Neuville, Jessica; De Witte, Philippe

in Psychopharmacology (1998), 139

Excitatory amino acid neurotransmission within the amygdala has been implicated in learning associations between external stimuli and intrinsic reward values, such that it may play a key role in ... [more ▼]

Excitatory amino acid neurotransmission within the amygdala has been implicated in learning associations between external stimuli and intrinsic reward values, such that it may play a key role in conditioned drug effects. In the present studies, the responses of the excitatory amino acids, aspartate and glutamate, together with the neuromodulatory sulphonated amino acid, taurine, within the basolateral amygdala, to an odor cue repeatedly associated with acute ethanol injections (2 g/kg, IP) have been investigated by a microdialysis technique combined with HPLC-EC analysis. After presentation of the ethanol-conditioned stimulus, a single IP saline injection induced an immediate and significant increase in the taurine microdialysate content which could be related to the neuromodulatory action of taurine. Furthermore, when the conditioned stimulus was combined with the ethanol injection (2 g/kg, IP), significant increases in both taurine and glutamate microdialysate content were observed and indicated a learned compensatory response to counteract the acute effects of ethanol. These results demonstrate that changes in amygdala extracellular glutamate and taurine concentrations can be conditioned to ethanol-associated stimuli and are therefore probably implicated in the phenomenon of environmental-dependent tolerance to ethanol. [less ▲]

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