16 research outputs found
ALIMENTATION DU FURET (MUSTELA PUTORIUS FURO)
L'utilisation répandue du furet dans la recherche biomédicale et l'intérêt sans cesse croissant qu'il suscite comme animal de compagnie génèrent une demande de plus en plus pressante concernant l'élaboration et la mise sur le marché d'un aliment spécifiquement adapté à ses exigences nutritionnelles particulières. En effet, le furet, comme notre chat domestique, est un carnivore strict. Mais une physiologie digestive originale lui impose de recevoir régulièrement une alimentation d'excellente qualité nutritionnelle, hautement digestible, riche en lipides et en protéines, et pauvre en fibres. Et ses besoins sont encore accrus lors de phases physiologiquement sensibles, telles que la croissance, la gestation ou la lactation. Chez le furet, l'alimentation est, à elle seule, le facteur le plus important pour garder l'animal en bonne santé et en pleine forme. Dans cette thèse, l'auteur analyse donc les besoins nutritionnels particuliers du furet à chaque stade physiologique de sa vie et étudie dans le détail les différentes pathologies liées de prés ou de loin à son alimentation. Car les déséquilibres ou les erreurs de formulation de la ration peuvent causer des troubles, parfois graves, mais le comportement même du propriétaire est aussi souvent à l'origine de soucis nutritionnels plus ou moins important (obésité, corps étrangers digestifs, intoxications ou infections, . . . ). Pour comprendre et éviter ces erreurs, la dernière partie est consacrée à l'analyse des différents aliments industriels disponibles sur le marché et susceptibles de satisfaire aux besoins nutritionnels du furet. Comme les aliments spécifiques sont encore rares et difficiles à se procurer, les possesseurs de ce nouvel animal de compagnie se verront souvent contraint de recourir à l'utilisation d'aliments industriels pour chats. Des clés leurs sont données pour leurs permettre de juger succinctement de la qualité et de l'adéquation d'un aliment aux exigences du furet.MAISONS-ALFORT-Ecole Vétérin (940462302) / SudocSudocFranceF
The activity of the sympathetic nervous system, assessed by power spectral analysis of heart rate variability, in whitecoat, masked and sustained hypertension
Abstract
OBJECTIVE:
To assess, in a population-based approach, sympathetic nervous system activity by the use of power spectral analysis of heart rate variability, in normotension, white-coat hypertension, masked hypertension and sustained hypertension.
METHODS:
The electrocardiographic RR interval was registered in the supine and standing positions and the low-frequency and high-frequency components of its variability were quantified. Cut-off values of 140/90 mmHg for conventional blood pressure and 135/85 mmHg for daytime ambulatory blood pressure were used to define the four blood pressure groups.
RESULTS:
After exclusion of patients with diabetes, myocardial infarction or treated hypertension, 1485 subjects with complete data remained for the analysis in the supine position. Age averaged 39 +/- 14 years; 54% were women. Conventional and ambulatory blood pressure averaged, respectively, 122 +/- 16/79 +/- 11 mmHg and 124 +/- 12/77 +/- 8 mmHg. After adjusting for demographic, anthropometric and lifestyle characteristics, the low-frequency to high-frequency ratio (geometric mean) averaged 0.81 in normotension and was significantly higher in white-coat hypertension (1.11; P < 0.001), based on a higher low-frequency component and a lower high-frequency component (P < 0.01). This ratio was not significantly different between normotension, masked hypertension (0.97) and sustained hypertension (0.93). The adjusted standing-to-supine ratio of the high-frequency component (geometric mean) was significantly higher in sustained hypertension (0.50) than in normotension (0.39; P < 0.01), but not in white-coat (0.40) and masked hypertension (0.45).
CONCLUSION:
The findings at rest are compatible with increased sympathetic activity and decreased parasympathetic modulation in white-coat hypertension, with normal autonomic cardiac regulation in masked and sustained hypertension. In addition, sustained hypertension is characterized by a blunted decrease of the high-frequency component on standing
THE ACTIVITY OF THE SYMPATHETIC NERVOUS SYSTEM, ASSESSED BY POWER SPECTRAL ANALYSIS OF HEART RATE VARIABILITY, IN WHITE-COAT, MASKED AND SUSTAINED HYPERTENSION
OBJECTIVE:
To assess, in a population-based approach, sympathetic nervous system activity by the use of power spectral analysis of heart rate variability, in normotension, white-coat hypertension, masked hypertension and sustained hypertension.
METHODS:
The electrocardiographic RR interval was registered in the supine and standing positions and the low-frequency and high-frequency components of its variability were quantified. Cut-off values of 140/90 mmHg for conventional blood pressure and 135/85 mmHg for daytime ambulatory blood pressure were used to define the four blood pressure groups.
RESULTS:
After exclusion of patients with diabetes, myocardial infarction or treated hypertension, 1485 subjects with complete data remained for the analysis in the supine position. Age averaged 39 +/- 14 years; 54% were women. Conventional and ambulatory blood pressure averaged, respectively, 122 +/- 16/79 +/- 11 mmHg and 124 +/- 12/77 +/- 8 mmHg. After adjusting for demographic, anthropometric and lifestyle characteristics, the low-frequency to high-frequency ratio (geometric mean) averaged 0.81 in normotension and was significantly higher in white-coat hypertension (1.11; P < 0.001), based on a higher low-frequency component and a lower high-frequency component (P < 0.01). This ratio was not significantly different between normotension, masked hypertension (0.97) and sustained hypertension (0.93). The adjusted standing-to-supine ratio of the high-frequency component (geometric mean) was significantly higher in sustained hypertension (0.50) than in normotension (0.39; P < 0.01), but not in white-coat (0.40) and masked hypertension (0.45).
CONCLUSION:
The findings at rest are compatible with increased sympathetic activity and decreased parasympathetic modulation in white-coat hypertension, with normal autonomic cardiac regulation in masked and sustained hypertension. In addition, sustained hypertension is characterized by a blunted decrease of the high-frequency component on standing
Context-dependency of relations between cardiovascular phenotypes and genes involved in sodium homeostasis: Findings from the European Project on Genes in Hypertension
Hypertension is a chronic age-related disorder, affecting nearly 20% of all adult Europeans. This disease entails debilitating cardiovascular complications and is the leading cause for drug prescriptions in Europeans older then 50 years. Intensive research over the past two decades failed so far to identify common genetic polymorphisms with major impact on blood pressure or associated cardiovascular phenotypes, suggesting that multiple genes each with a minor impact, along with gene-gene and gene-environment interactions play a role. The European Project on Genes in Hypertension (EPOGH) is a large-scale family-based study, in which participants from 7 different populations were phenotyped and genotyped according to standardised procedures. This review article summarizes the initial 5-year findings and puts these observations into perspective against other published studies. EPOGH demonstrated that phenotype-genotype relations strongly depend on host factors, such as gender and lifestyle, in particular salt intake as reflected by the 24-hour urinary excretion of sodium. EPOGH therefore highlights the concept that phenotype-genotype relations can only be studied within a defined ecogenetic context. \ua9 2006 Bentham Science Publishers Ltd
Context-dependency of relations between cardiovascular phenotypes and genes involved in sodium homeostasis : findings from the European Project on Genes in Hypertension
Hypertension is a chronic age-related disorder, affecting nearly 20% of all adult Europeans. This disease entails debilitating cardiovascular complications and is the leading cause for drug prescriptions in Europeans older then 50 years. Intensive research over the past two decades failed so far to identify common genetic polymorphisms with major impact on blood pressure or associated cardiovascular phenotypes, suggesting that multiple genes each with a minor impact, along with gene-gene and gene-environment interactions play a role. The European Project on Genes in Hypertension (EPOGH) is a large-scale family-based study, in which participants from 7 different populations were phenotyped and genotyped according to standardised procedures. This review article summarizes the initial 5-year findings and puts these observations into perspective against other published studies. EPOGH demonstrated that phenotype-genotype relations strongly depend on host factors, such as gender and lifestyle, in particular salt intake as reflected by the 24-hour urinary excretion of sodium. EPOGH therefore highlights the concept that phenotype-genotype relations can only be studied within a defined ecogenetic context. © 2006 Bentham Science Publishers Ltd.status: publishe
Genetic variation in CYP11B2 and AT1R influences heart rate variability conditional on sodium excretion
Sympathetic tone increases with stimulation of the renin-angiotensin system and is under the influence of salt intake. In the European Project On Genes in Hypertension (EPOGH), we investigated whether polymorphisms in the genes encoding aldosterone synthase (CYP11B2 C-344T) and the type-1 angiotensin II receptor (AT1R A1166C) affect the autonomic modulation of heart rate at varying levels of salt intake. We measured the low frequency (LF) and high frequency (HF) components of heart rate variability and their ratio (LF:HF) in the supine and standing positions in 1797 participants (401 families and 320 unrelated subjects) randomly selected from 6 European populations, whose average urinary sodium excretion ranged from 163 to 245 mmol/d. In multivariate analyses with sodium excretion analyzed as a continuous variable, we explored the phenotype-genotype associations using generalized estimating equations and quantitative transmission disequilibrium tests. Across populations, there was no heterogeneity in the phenotype-genotype relations. The genotypic effects differed according to sodium excretion. In subjects with sodium excretion 190 mmol/d, these associations with the CYP11B2 and AT1R polymorphisms were nonsignificant or in the opposite direction, respectively. Thus, CYP11B2 C-344T and AT1R A1166C polymorphisms affect the autonomic modulation of heart rate, but these genetic effects depend on sodium excretion