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Summary Aim To assess the effects of water immersion on cardiovascular requirements, 30 min immersed versus air steady exercises at neutral temperature were compared in two settings:similar energy expenditure (60% maximal oxygen consumption; series 1) and similar ergometric workload (120 W; series 2). For 15 healthy male subjects, the arterial blood pressure, heart rate, thoracic fluid conductivity (TFC), cardiac index (CI) and stroke index (SI) were monitored at rest, during the exercise period and during 30 min of post-exercise recovery in two conditions. Plasma atrial natriuretic peptide (ANP) was also measured. Results Resting water immersion increased TFC, CI, SI, and systolic arterial pressure (SAP). During exercise the average CI, SI and SAP were not different in water and air in series 1, but in series 2 CI, SI, heart rate, systolic and diastolic arterial pressures were higher in water. Plasma ANP was higher after immersed exercises. During recovery, CI was similar after either exercise, while SI was lower and heart rate higher following immersion, consistent with a lower effective circulatory volume than after exercise in air. TFC was high, as reflecting an increased interstitial fluid content in the lung. Conclusions Cardiovascular requirements for exercising in water were markedly higher than in air and straining of lung parenchyma.

Resume Objectifs. – Les etudes destinees a determiner les valeurs diagnostiques des tests de l'allergie aux venins d’hymenopteres ont ete souvent realisees dans un objectif de validation methodologique, mais on dispose de tres peu d’etudes d’evaluation dans des situations de routine diagnostique. De fait, la valeur diagnostique des tests de liberation d'histamine, par exemple, a rarement ete etudiee systematiquement chez des patients adresses par leur medecin pour une confirmation diagnostique et/ou l’indication d’une desensibilisation. Le but de cette etude etait d'evaluer les valeurs diagnostiques des prick-tests, des IgE specifiques et des tests de liberation d'histamine en pratique de routine dans une unite d'allergologie. Patients et methode. – Les tests diagnostiques ont ete realises prospectivement chez 25 patients consecutifs atteints d’allergie aux venins d'hymenopteres attestee par l'histoire clinique et la positivite des intradermo-reactions, incluant des patients avec reaction locoregionale accompagnee de malaise et/ou de dyspnee, de meme que chez 21 sujets temoins. Les hymenopteres etudies ont ete la guepe Vespula (V) et l’abeille (A). Ont ete etudiees : la sensibilite, la specificite, la concordance et les valeurs predictives. Resultats. – Les valeurs de sensibilite, specificite, valeur predictives positives et negatives ont ete respectivement de (en pourcentage) : pour les prick-tests (100 μg/mL) : 33,3 ; 100 ; 100 ; 85,7 (A) ; 30 ; 100 ; 100 ; 85,1 (V) ; pour les prick-tests (300 μg/mL) : 75 ; 100 ; 100 ; 94,1 (A) ; 57,1 ; 100 ; 100 ; 90,3 (V) ; pour les IgE specifiques : 100 ; 95,2 ; 84 ; 100 (A) ; 100 ; 76,2 ; 51,2 ; 100 (V) ; et pour le test de liberation d’histamine : 88,9 ; 100 ; 100 ; 97,3 (A) ; 94,1 ; 88,9 ; 67,9 ; 98,4 (V). Conclusions. – Pour le diagnostic de l’allergie aux hymenopteres par les prick-tests, des concentrations de venins inferieures a 300 μg/mL sont trop peu sensibles. Le test de liberation d'histamine represente un bon test complementaire dont la standardisation devrait etre amelioree.

The aim of the present study was to investigate the effects of a delayed bedtime (3 a.m.), an advanced rising (3 a.m.), a sleep under placebo and under a hypnotic compound, i.e. 10 mg of Zolpidem (Stilnox®) on sleep structure and on the adaptations to a subsequent exercise in 8 male athletes. The chronology of these nights was randomized and each treatment administered in a double blind fashion. During each experimental night, subjects were monitored with conventional EEG/EOG/EMG polygraphic recordings. The next day, athletic performance was tested using a bicycle ergometer. A codified exercise was performed and consisted to a 10 min warm up followed by a 30 min steady state cycling corresponding to 75% of predetermined VO2 max. Then the work load increased progressively by steps of 10 W every minute until exhaustion. The recovery lasted 30 min. Heart rate, ventilation, VO2, ERO2 were monitored during all exercise and recovery. Plasma lactates and catecholamines were also measured at the same ti...

The present study compared the effects of partial sleep deprivation and the effects of an intake of a hypnotic compound (zolpidem) prior to bedtime, on sleep and on hormonal and metabolic adaptations to subsequent exercise. Sleep deprivation consisted of a delayed bedtime and an early getting-up time. Eight young subjects, who slept well and were highly trained athletes, were enrolled in this study. Sleep was recorded polygraphically and the following afternoon exercise was performed on a cycle ergometer for 30 min at 75% of maximal oxygen consumption (VO2max) after a 10-min warm up. Met-enkephalin, β-endorphin, cortisol, and lactate concentrations were measured at rest and during exercise. The data obtained after experimental sleep, with and without medication were compared with those obtained in the reference condition with normal sleep. Both types of sleep reduction decreased the total sleep time, stage 2 sleep, and rapid eye movement sleep, whereas zolpidem administration did not modify either the duration of sleep or the sleep stages. After the reference night, plasma met-enkephalin did not show any significant change at the end of the submaximal exercise, whereas β-endorphin, cortisol, and lactic acid concentrations increased significantly in all subjects. The changes in concentration in β-endorphin were significantly related to the changes in cortisol (r=0.78;P

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Cytochrome P450-2D6 may be involved in the metabolism of many drugs such as psychotropic drugs and its genetic polymorphism is responsible for inter-individual differences in the therapeutic effect and toxicity of these drugs. Moreover with the same genetic basis, CYP2D6 metabolic capacity variations are observed. Different factors of variation may be involved, among them the prescribed drugs. The aim of this study was to compare the influence of two types of antidepressants, tricyclic (clomipramine) and serotonergic specific recapture inhibitor (SSRI) (fluoxetine), on the CYP2D6 metabolic capacity of depressed inpatients. The CYP2D6 phenotype (dextromethorphan test) was determined in 56 genotyped (PCR-SSCP) depressed caucasian inpatients with a heterozygous genotype. Forty-five subjects were treated with clomipramine and eleven received fluoxetine. The dextromethorphan metabolic ratio (MR) median was significantly higher in the fluoxetine group (0.255) than in the clomipramine group (0.083, p < 0.014). In this study, fluoxetine involved a greater decrease of CYP2D6 metabolic capacity than clomipramine. Clinical implications and the possible connection between a decreased CYP2D6 activity and adverse drug effects were discussed. Caution should be taken when drugs with a low therapeutic index must be coprescribed in such patients.

The aim of the study was to investigate the effects of a partial sleep deprivation on a subsequent supramaximal exercise evaluated from the 30 second Wingate test, and on the following recovery. To take into account the active muscle mass, the Wingate test was performed against a constant braking force related to the data of a force-velocity test conducted on a Monark cycle ergometer (Model 814 E with weights) one week before the experimental test. Eight highly trained athletes were enrolled for this study. The changes in ventilatory and metabolic responses were analyzed during and upon completion of physical 30 second exercise, taking place after two nights, in other words, after a reference night and after a night with reduced sleep. Partial sleep deprivation was obtained by delaying bedtime until 3 a.m. The 30 second Wingate test was performed between 9 a.m. and noon the following days, using a Monark ergometer (Model 814 F). The analyses of change scores disclosed that there were no main significant effects for measures of ventilation, lactates and pH(v) levels under the two experimental conditions. The peak power, the mean power output and the peak velocity recorded after partial sleep deprivation were not modified in comparison with the values obtained after the reference night. These findings suggest that acute sleep loss did not contribute to alterations in supramaximal exercise.

The purpose of the study was to compare the cardiovascular, respiratory and metabolic responses to exercise of highly endurance trained subjects after 3 different nights i.e. a baseline night, a partial sleep deprivation of 3 h in the middle of the night and a 0.25-mg triazolam-induced sleep. Sleep-waking chronobiology and endurance performance capacity were taken into account in the choice of the subjects. Seven subjects exercised on a cycle ergometer for a 10-min warmup, then for 20 min at a steady exercise intensity (equal to the intensity corresponding to 75% of the predetermined maximal oxygen consumption) followed by an increased intensity until exhaustion. The night with 3 h sleep loss was accompanied by a greater number of periods of wakefulness (P

Immersion is considered to facilitate exercise-based rehabilitation. However, the drag effect of moving limbs in water, likely to increase the respiratory requirements at exercise, is not mentioned in many reports. The energetic and ventilatory requirements of 30 min steady state cycling exercise performed by healthy male subjects in air and during immersion up to the xiphoid in 33 degrees C water were compared. In the first experimental series nine subjects exercised at the same 60% maximal oxygen consumption (V'O2,max) in air and water. In the two ambient conditions, ventilatory variables had similar values, but the ergometric setting had to be reduced during water immersion so that the workload rated only 69+/-20 W (mean+/-SD) in water versus 121+/-32 W (p

1. During a 28-day treatment period, 10 healthy volunteers in a cross-over, double-blind study received at random 200 mg of either acebutolol or labetalol twice a day. Each treatment period was followed by administration of a placebo over an equal length of time. 2. Only acebutolol reduced heart rate measured in the supine position significantly at rest, whereas acebutolol and labetalol reduced it significantly after exercise on the treadmill. 3. Only acebutolol lowered humeral pressure at rest but not after exercise. Neither drug produced a change in blood pressure in the ankle or in the first toe at rest or after exercise. 4. Blood flow measured by plethysmography was increased by labetalol in the calf by comparison with placebo and in the first toe by comparison with placebo and acebutolol. 5. Labetalol lowered peripheral resistance significantly in comparison with placebo in the calf and first toe. Acebutolol tended to lower the resistance insignificantly in the calf but to increase resistance in the first toe.

The present study illustrates the importance of bioavailability testing whenever two active ingredients are combined in the same formulation in order to be administered simultaneously. The negative influence of the major spasmolytic drug, tiemonium, on the absorption of aspirin was demonstrated in the dog. This activity is so important that it was logical to suppose that this effect would be the same in man. In order to remove this effect, a special formulation was designed in which the two ingredients were released one after the other. Even so, an initial experiment in man gave unexpected results which were shown in an in vitro study to be due to extraneous factors connected with the preparation of the tablets. The importance of such in vitro investigations in avoiding hasty interpretation of in vivo findings is thus once again demonstrated.