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1.
Int J Sports Med ; 27(4): 301-6, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16572373

ABSTRACT

We examined the effect of normobaric hypoxia (3200 m) on maximal oxygen uptake (VO2max) and maximal power output (Pmax) during leg and upper-body exercise to identify functional and structural correlates of the variability in the decrement of VO2max (DeltaVO2max) and of maximal power output (DeltaPmax). Seven well trained male Nordic combined skiers performed incremental exercise tests to exhaustion on a cycle ergometer (leg exercise) and on a custom built doublepoling ergometer for cross-country skiing (upper-body exercise). Tests were carried out in normoxia (560 m) and normobaric hypoxia (3200 m); biopsies were taken from m. deltoideus. DeltaVO2max was not significantly different between leg (-9.1+/-4.9%) and upper-body exercise (-7.9+/-5.8%). By contrast, Pmax was significantly more reduced during leg exercise (-17.3+/-3.3%) than during upper-body exercise (-9.6+/-6.4%, p<0.05). Correlation analysis did not reveal any significant relationship between leg and upper-body exercise neither for DeltaVO2max nor for DeltaPmax. Furthermore, no relationship was observed between individual DeltaVO2max and DeltaPmax. Analysis of structural data of m. deltoideus revealed a significant correlation between capillary density and DeltaPmax (R=-0.80, p=0.03), as well as between volume density of mitochondria and DeltaPmax (R=-0.75, p=0.05). In conclusion, it seems that VO2max and Pmax are differently affected by hypoxia. The ability to tolerate hypoxia is a characteristic of the individual depending in part on the exercise mode. We present evidence that athletes with a high capillarity and a high muscular oxidative capacity are more sensitive to hypoxia.


Subject(s)
Hypoxia/physiopathology , Leg/physiology , Muscle, Skeletal/pathology , Oxygen Consumption/physiology , Skiing/physiology , Upper Extremity/physiology , Acute Disease , Adult , Biopsy, Fine-Needle , Ergometry , Heart Rate/physiology , Humans , Lactic Acid/blood , Male , Muscle, Skeletal/blood supply , Muscle, Skeletal/physiology
2.
Biopharm Drug Dispos ; 18(6): 489-97, 1997 Aug.
Article in English | MEDLINE | ID: mdl-9267682

ABSTRACT

Letrozole is a new non-steroidal inhibitor of the aromatase enzyme system. It is currently under development for the treatment of postmenopausal women with advanced breast cancer. To investigate the influence of food on the bioavailability of letrozole, 12 healthy male volunteers were treated under fed and fasted conditions with single oral doses of 2.5 mg letrozole in film-coated tablets. Plasma concentration profiles were determined. No significant difference in the extent of absorption (AUC or AUC0-8 h) was observed between the two treatments but the rate of letrozole absorption decreased slightly under fed conditions. However, in view of the half-life of about 2 d this small change in the absorption rate is not considered to be of clinical relevance for treatment with repeated administrations.


Subject(s)
Aromatase Inhibitors , Enzyme Inhibitors/pharmacokinetics , Food-Drug Interactions , Nitriles/pharmacokinetics , Triazoles/pharmacokinetics , Absorption , Administration, Oral , Adult , Analysis of Variance , Area Under Curve , Biological Availability , Cross-Over Studies , Eating , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/blood , Fasting/blood , Humans , Letrozole , Male , Nitriles/administration & dosage , Nitriles/blood , Reproducibility of Results , Tablets, Enteric-Coated , Triazoles/administration & dosage , Triazoles/blood
3.
Eur J Clin Pharmacol ; 52(6): 441-9, 1997.
Article in English | MEDLINE | ID: mdl-9342579

ABSTRACT

OBJECTIVE: Pharmacokinetics, pharmacodynamic effects and tolerability of 200 mg valsartan, once-daily for 8 days, were investigated in 16 healthy, normotensive volunteers on a normal sodium diet. METHODS: This was a double-blind, placebo-controlled, randomized crossover study. Drug concentrations in plasma and urine, angiotensin II (Ang II) concentrations in plasma, systolic (SBP) and diastolic (DBP) blood pressure, heart rate (HR) in the supine position and 3 min after passive head-up tilting, as well as safety parameters (ECG, clinical chemistry and hematology, renal water and electrolyte excretion) were measured over 24 h after the first dose (day 1) and at steady state on day 8. RESULTS: Absorption and distribution of valsartan were rapid (Cmax, 2 h; t1/2 lambda 1 < 1 h), followed by a slower terminal elimination phase (t1/2 lambda 2, 6 h) on days 1 and 8, with little accumulation in plasma (increase of 20% on day 8). Less than 10% of the dose was excreted unchanged in urine. The increase in plasma Ang II (Cmax, 6 h) was significantly enhanced at steady state. Supine SBP and DBP significantly decreased on day 8 only, by an average of -3.6 and -2.4 mmHg, respectively, versus placebo, without a concomitant increase in HR. Upon passive tilting, the increase in DBP, normally reinforced by sympathetic renin release, was slightly but significantly blunted on day 1 (-2.0 mmHg) and day 8 (-4.0 mmHg) of treatment with valsartan versus placebo. The orthostatic reflex increase in HR was slightly enhanced compared with placebo by an average of 2.8 beats min-1 on day 1 and by 2.9 beats.min-1 on day 8. Valsartan was well tolerated and had no influence on ECG, clinical laboratory parameters, and water, electrolyte and uric acid excretion. CONCLUSIONS: Pharmacokinetics of valsartan are unchanged after multiple once-daily dosing, with little (expected) accumulation in plasma. Effects of 200 mg valsartan on blood pressure in healthy subjects on a normal sodium intake are small and become more prominent after repeated dosing. Indirect evidence of AT1 blockade by valsartan is demonstrated by an increase of plasma Ang II and by a blunted DBP response to passive tilting. The decrease in blood pressure at steady state enhances the increase in plasma Ang II. Valsartan is well tolerated and is devoid of effects on water, electrolyte and uric acid excretion at 200 mg per day in healthy normotensive volunteers.


Subject(s)
Antihypertensive Agents/pharmacology , Antihypertensive Agents/pharmacokinetics , Blood Pressure/drug effects , Heart Rate/drug effects , Tetrazoles/pharmacology , Tetrazoles/pharmacokinetics , Valine/analogs & derivatives , Adult , Angiotensin II/blood , Area Under Curve , Cross-Over Studies , Double-Blind Method , Half-Life , Humans , Male , Metabolic Clearance Rate , Middle Aged , Valine/pharmacokinetics , Valine/pharmacology , Valsartan
4.
Eur J Clin Pharmacol ; 52(6): 451-9, 1997.
Article in English | MEDLINE | ID: mdl-9342580

ABSTRACT

OBJECTIVE: Valsartan (V), a specific inhibitor of the angiotensin II receptor subtype, AT1, has been developed for treatment of hypertension. Combination therapy with a beta-adrenoceptor blocking agent might be considered in cases with insufficient efficacy of V alone. Therefore, an interaction trial was performed to evaluate the effects of co-administration of V on the pharmacokinetics of atenolol (A), and vice versa, and to monitor the pharmacodynamic response of plasma angiotensin II (ANG II) concentrations and plasma renin activity (PRA), as well as of heart rate and blood pressure, under resting and exercise conditions. METHODS: Twelve healthy, normotensive, male volunteers aged 23-46 years were treated with single doses of either 160 mg V or 100 mg A alone, or with both drugs in combination (V + A) according to a three-period crossover design. Plasma concentrations of V and A were determined using HPLC with fluorimetric and UV detection, respectively, and concentration-time profiles were established over 24 h. Plasma ANG II concentrations and PRA were monitored using specific radioimmunoassays. Heart rate and blood pressure were measured at rest and during exercise on a cycle ergometer at a workload of 2.5 W/kg-1. RESULTS: For V, mean AUC and Cmax were slightly higher when A was co-administered, the ratios of log transformed values being 1.13 and 1.22 for AUC(0-inf) and Cmax, respectively. For A, mean AUC and Cmax were slightly lower when the drug was given in combination with V. The ratios of log-transformed values in this case were 0.90 and 0.92, respectively. The sharp increase in plasma ANG II concentrations and PRA, induced by administration of V, was significantly attenuated when the drug was combined with A. In the first 12 h after drug intake, heart rate and systolic blood pressure at rest were significantly decreased when V and A were co-administered compared with treatment with V alone. V given alone did not influence heart rate or systolic blood pressure during exercise, whereas A alone and V + A led to a significant reduction in those variables. Adverse experiences reported after A and V + A could be explained by the high degree of beta-adrenoceptor blockade resulting from the administration of A. CONCLUSIONS: Co-administration of single doses of V and A does not modify the pharmacokinetics of the two drugs to a clinically relevant degree. With respect to pharmacodynamics, a single dose of A attenuates the increase in plasma ANG II and PRA in response to a single dose of V, and V has no effect on the hemodynamic response to exercise. The combined treatment with single doses of 160 mg V and 100 mg A has some additive effects on resting blood pressure in healthy, normotensive subjects.


Subject(s)
Adrenergic beta-Antagonists/pharmacology , Adrenergic beta-Antagonists/pharmacokinetics , Antihypertensive Agents/pharmacology , Antihypertensive Agents/pharmacokinetics , Atenolol/pharmacology , Atenolol/pharmacokinetics , Blood Pressure/drug effects , Heart Rate/drug effects , Tetrazoles/pharmacology , Tetrazoles/pharmacokinetics , Valine/analogs & derivatives , Adult , Angiotensin II/blood , Area Under Curve , Cross-Over Studies , Drug Interactions , Exercise , Half-Life , Humans , Male , Metabolic Clearance Rate , Renin/blood , Valine/pharmacokinetics , Valine/pharmacology , Valsartan
5.
Biopharm Drug Dispos ; 18(9): 779-89, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9429742

ABSTRACT

Letrozole is a new non-steroidal inhibitor of the aromatase enzyme system. It is currently under development for the treatment of postmenopausal women with advanced breast cancer. Absolute bioavailability of letrozole when given orally as one 2.5 mg film-coated tablet in comparison to the same dose given intravenously as a bolus injection was studied in 12 healthy postmenopausal women. Letrozole absolute systemic bioavailability after p.o. administration was 99.9 +/- 16.3%. Elimination of letrozole was slow. Total-body clearance of letrozole from plasma after i.v. administration was low (2.21 L h-1). The calculated distribution volume at steady state (1.87 L kg-1) suggests a rather high tissue distribution. Biotransformation of letrozole is the main elimination mechanism with the glucuronide conjugate of the secondary alcohol metabolite being the predominant species found in urine. The two study treatments were tolerated equally well.


Subject(s)
Aromatase Inhibitors , Enzyme Inhibitors/pharmacokinetics , Nitriles/pharmacokinetics , Postmenopause/blood , Triazoles/pharmacokinetics , Administration, Oral , Area Under Curve , Biological Availability , Biotransformation , Chromatography, High Pressure Liquid , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/blood , Female , Humans , Injections, Intravenous , Letrozole , Middle Aged , Nitriles/administration & dosage , Nitriles/blood , Regression Analysis , Tissue Distribution , Triazoles/administration & dosage , Triazoles/blood
7.
Int J Sports Med ; 16(6): 343-6, 1995 Aug.
Article in English | MEDLINE | ID: mdl-7591382

ABSTRACT

We measured changes in maximal oxygen uptake capacity (VO2max), ventilation, heart rate, plasma lactate and speed at the end of an incremental exercise test as a consequence of a relay foot race from Paris to Dakar in 6 subjects. Additionally, anthropometric measurements were taken and muscle biopsies from M. vastus lateralis were obtained before and after the race. The latter were analyzed with morphometric methods for fiber size, capillarity and muscle ultrastructural composition. Weight specific VO2max was significantly reduced from 62.4 to 60.5 ml/min.kg after the race while absolute VO2max and the other endurance related functional variables remained unchanged. Body fat, thigh cross-sectional area and thigh volume showed tendential reduction immediately after the race but regained pre-race values within a few days. Fiber size and capillarity were not affected by the race. Volume density of total mitochondria was significantly reduced from 6.98 to 4.89% of fiber volume. Both subsarcolemmal and interfibrillar mitochondria were significantly reduced by 59 and 21%, respectively. The volume density of satellite cell was increased about three-fold whereas the content of lipofuscin remained constant. It is concluded that extreme endurance events such as a multi-stage relay race may induce a considerable loss of oxidative capacity of skeletal muscle tissue.


Subject(s)
Muscle, Skeletal/metabolism , Oxygen Consumption/physiology , Physical Endurance , Running/physiology , Adipose Tissue/anatomy & histology , Adult , Anthropometry , Capillaries/ultrastructure , Exercise Test , Heart Rate , Humans , Lactates/blood , Lipofuscin/analysis , Male , Mitochondria, Muscle/ultrastructure , Muscle Fibers, Skeletal/ultrastructure , Muscle, Skeletal/anatomy & histology , Muscle, Skeletal/blood supply , Muscle, Skeletal/ultrastructure , Paris , Respiration , Sarcolemma/ultrastructure , Senegal , Thigh/anatomy & histology
8.
Schweiz Med Wochenschr ; 125(16): 796-801, 1995 Apr 22.
Article in German | MEDLINE | ID: mdl-7732353

ABSTRACT

To determine the prevalence of tuberculosis infection in Switzerland, standardized tuberculin tests using 2 units of tuberculin Berna PPD RT 23, administered by specially trained personnel, were performed on school leavers in 3 Swiss cantons in 1992/1993. Of the 7036 school leavers, averaging 15 years of age, only 294 (4.18%) were not BCG-vaccinated. Non-vaccinated persons had tuberculin test indurations > 15 mm in 2.04% (6663 BCG vaccinated persons in 1.14%). Calculations of potentially influential factors using stepwise ordinal polychotomous regression showed that tuberculin test indurations are significantly larger after BCG vaccination, as well as with increasing age at immigration from high prevalence tuberculosis countries. Indurations were smaller with increasing time passed since BCG vaccination, as well as in females. Pets at home did not significantly influence the size of tuberculin reactions. Theoretically the positive predictive value of tuberculin tests in Switzerland is small because of the low tuberculosis prevalence. From our data the maximal prevalence of infection in 15-year-olds is estimated at 0.91% (2.48% in the non-vaccinated) in Swiss and 2.54% (9.77% in the non-vaccinated) in foreign born school children. These rates, higher than extrapolated from previous studies, are comparable to data from other industrialized countries. They do not warrant a change in BCG vaccination policy in Switzerland, which since 1987 requires BCG vaccination in children immigrating from countries with high tuberculosis prevalence only.


Subject(s)
Tuberculin Test , Tuberculosis/epidemiology , Adolescent , Age Factors , BCG Vaccine , Child , Emigration and Immigration , Female , Humans , Male , Predictive Value of Tests , Prevalence , Regression Analysis , Sex Factors , Tuberculosis/diagnosis , Tuberculosis/prevention & control
9.
J Adolesc Health ; 15(3): 258-62, 1994 May.
Article in English | MEDLINE | ID: mdl-8075098

ABSTRACT

PURPOSE: This study aimed at assessing the impact of physical training on psychological functioning at the onset of a prospective study of psychological and somatic maturation of adolescent female athletes. METHODS: Twenty-seven highly trained gymnasts aged 12.7 +/- 1.1 year (mean +/- SD, training load = 18-26 hr/week) and 16 age-matched but moderately trained swimmers (13.0 +/- 0.9 yr, training load 4-15 hr/wk) were submitted to standardized somatic and psychiatric examinations during training camps. RESULTS: Gymnasts were significantly shorter, lighter and thinner (p < 0.001) than swimmers. Their bone age was moderately but significantly retarded (-1.42 +/- 0.99 yr, p < 0.001) in contrast with swimmers in whom it was adequate for chronological age (+0.28 +/- 0.94 year, ns). Only 7.4% of gymnasts had already had menarche in contrast with 50% of age-matched swimmers (p = 0.003). Psychological functioning was considered as normal in all subjects. However, seven athletes including 3/27 gymnasts and 4/16 swimmers (p = 0.394) were considered as subjects "at risk" to develop a manifest mental disorder over time. Ten gymnasts (41.7%) presented with a global delay in psychological maturation, whereas no such case was observed among swimmers (p = 0.015). No correlation could be established between psychological delay and pubertal retardation (p = 0.210). CONCLUSION: Strenuous training in gymnastics for more than 1 yr has so far no detectable interference with the normal maturational events of adolescence. The outcome of athletes at risk to develop psychopathology as well as those with a global delay in psychological maturation who presented as if they were still in the latency period, remains uncertain.


Subject(s)
Growth , Gymnastics/physiology , Gymnastics/psychology , Human Development , Psychology, Adolescent , Swimming/physiology , Swimming/psychology , Adolescent , Age Determination by Skeleton , Child , Female , Growth Disorders/diagnosis , Growth Disorders/epidemiology , Humans , Matched-Pair Analysis , Menarche , Mental Disorders/diagnosis , Mental Disorders/epidemiology , Prospective Studies , Risk Factors
10.
Eur J Clin Pharmacol ; 47(3): 231-45, 1994.
Article in English | MEDLINE | ID: mdl-7867676

ABSTRACT

Valsartan (CGP 48933), a specific blocker of the angiotensin II (Ang II) receptor subtype 1 (AT1 receptor) was administered in single, oral doses of 40 mg and 80 mg to six healthy, normotensive male volunteers in a double-blind, placebo-controlled, randomized crossover trial. The aims of the study were a) to assess the extent, time course and dose-dependency of inhibition of the pressor effect of exogenous Ang II; and b) to attempt to correlate AT1 receptor blockade with the drug levels in plasma and with other markers of biological activity of the trial drug such as plasma renin activity (PRA). Using the Finapres device and i.v. bolus injections of exogenous Ang II, AT1 receptor blockade was assessed by measuring blood pressure (BP) and heart rate (HR) on a beat-by-beat basis. A dose-response curve for Ang II was obtained for each subject before and at 2, 4, 6, 8 and 24 h after administration of placebo and of the two doses of valsartan. PRA was measured with a conventional radioimmunoassay method. Data evaluation included a) descriptive analysis of the changes of the Ang II dose-response curves after valsartan, as compared to the curve on placebo; b) calculation of the pressor dose D30 of Ang II at each time-point, using linear regression; c) assessment of the effect of 4 micrograms Ang II on systolic BP and HR and the calculation of the percentage inhibition of these effects after valsartan; d) description of the relationship between drug levels in plasma and the measures of AT1 blockade, including pharmacokinetic-pharmacodynamic modeling with an Emax model for the percentage inhibition of systolic BP and HR.(ABSTRACT TRUNCATED AT 400 WORDS)


Subject(s)
Angiotensin Receptor Antagonists , Blood Pressure/drug effects , Tetrazoles/pharmacology , Valine/analogs & derivatives , Adult , Angiotensin II/antagonists & inhibitors , Angiotensin II/pharmacology , Cross-Over Studies , Dose-Response Relationship, Drug , Double-Blind Method , Drug Administration Schedule , Heart Rate/drug effects , Humans , Male , Placebos , Renin/blood , Reproducibility of Results , Systole/drug effects , Systole/physiology , Tetrazoles/blood , Tetrazoles/pharmacokinetics , Valine/blood , Valine/pharmacokinetics , Valine/pharmacology , Valsartan
11.
Schweiz Z Med Traumatol ; (3): 7-15, 1994.
Article in French | MEDLINE | ID: mdl-7921796

ABSTRACT

The hormonal response to a short but intense session of physical exercise should be distinguished from the endocrine adaptation to systematic physical conditioning. The normal child is perfectly equipped to handle stress situations such as those generated by leisure sport: the transient increase in stress hormones has no deleterious effect on growth and puberty. For highly trained children and adolescents, standardized dynamic testing will provide little information on the state of their endocrine system. In addition, the effects of training should be differentiated from those of various bias of selection. In young elite athletes, as for adult athletes, the alterations of the endocrine system result from an inappropriate physical conditioning programme for the individual level of tolerance. Whereas it has been shown that the gonadal function is predominantly affected (pubertal delay, menstrual dysfunction), alterations of growth hormone and cortisol productions have also been reported. Anomalies of pubertal growth should be searched for among elite adolescent athletes: there are data suggesting that their growth potential should probably not be affected below 15 weekly hours of training. However, children do not respond to stress in a uniform manner and one should be prepared to detect the occasional athlete with inadequate growth at lower training intensities. This seems to be the case when training starts before puberty as well as in physical activities associated with a strict weight control. When growth and/or puberal progression become inappropriate, the only logical therapy consists in reducing markedly or stopping training temporarily: in this situation, there is no medical justification whatsoever to initiate a substitutive therapy.


Subject(s)
Growth , Hormones/physiology , Sports/physiology , Adolescent , Child , Female , Gonadal Steroid Hormones/metabolism , Growth Hormone/metabolism , Hormones/metabolism , Humans , Male , Pituitary-Adrenal System/metabolism , Puberty/physiology , Thyroid Hormones/metabolism
12.
Biol Psychiatry ; 33(5): 373-9, 1993 Mar 01.
Article in English | MEDLINE | ID: mdl-8471696

ABSTRACT

The selective, reversible monoamine oxidase (MAO) A inhibitor brofaromine inhibits serotonin (5-HT) uptake in animal models in vitro and in vivo. We investigated whether such an effect can be demonstrated at clinical doses in humans by treating three groups of six volunteers with either placebo, 15 mg phenelzine three times a day, or 75 mg brofaromine twice a day in a 2-week experiment. As an indirect, although relevant parameter, binding of 3H-paroxetine to the 5-HT uptake sites on blood platelets was assessed. Moreover, whole-blood 5-HT as a measure of platelet 5-HT, and serum homovanillic acid (HVA) to tentatively estimate MAO inhibition, were determined. Brofaromine reduced 3H-paroxetine binding to platelets compared with placebo by 20%-25% throughout the treatment period, significance being reached on the last treatment day. In contrast, phenelzine tended to increase 3H-paroxetine binding. Both drugs increased whole-blood 5-HT to approximately 140%-150%. Brofaromine moderately and on some days significantly decreased serum HVA, whereas phenelzine only tended to do so. Our results suggest that brofaromine at the clinically used dosage of 150 mg/day does indeed inhibit 5-HT uptake, as evidenced by measurements of 3H-paroxetine binding to platelets.


Subject(s)
Depressive Disorder/drug therapy , Monoamine Oxidase Inhibitors/pharmacology , Piperidines/pharmacology , Selective Serotonin Reuptake Inhibitors/pharmacology , Adult , Depressive Disorder/metabolism , Homovanillic Acid/analysis , Homovanillic Acid/blood , Humans , Male , Paroxetine/blood , Paroxetine/metabolism , Piperidines/therapeutic use , Placebos/therapeutic use
13.
J Pediatr ; 122(2): 306-13, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8117341

ABSTRACT

The goal of this prospective study was to assess whether intensive physical training during puberty could alter the growth potential of adolescent female athletes. Height, sitting height, leg length, weight, body fat, and pubertal stage of 22 gymnasts aged 12.3 +/- 0.2 years (mean +/- SEM), with an average training period of 22 hr/wk, and of 21 swimmers aged 12.3 +/- 0.3 years (average training period 8 hr/wk) were recorded half-yearly for a mean period of 2.35 years (range 2.0 to 3.7 years). Adult height predictions were performed with the methods of Bayley and Pinneau; Roche, Wainer, and Thissen, and Tanner et al. Growth velocity of gymnasts was significantly lower than that of swimmers from 11 to 13 years of bone age (p < 0.05), with a mean peak height velocity of 5.48 +/- 0.32 cm/yr versus 8.0 +/- 0.50 cm/yr for swimmers. Height standard deviation score decreased significantly in gymnasts with time (r = -0.747; p < 0.001). This observation was not associated with a significant alteration of chronologic age/bone age ratio. By contrast, height standard deviation score remained unchanged in swimmers (r = -0.165; p = 0.1). A marked stunting of leg-length growth was observed in gymnasts from 12 years of bone age, resulting in a marked difference in overall sitting-height/leg-length ratio (gymnasts 1.054 +/- 0.005 vs swimmers 1.100 +/- 0.005; p < 0.001). Concomitantly, predicted height of gymnasts decreased significantly with time (Tanner et al.: r = 0.63, p < 0.001; Bayley-Pinneau: r = 0.44, p < 0.001), whereas those of swimmers did not change. We conclude that heavy training in gymnastics (> 18 hr/wk), starting before puberty and maintained throughout puberty, can alter growth rate to such an extent that full adult height will not be reached. The mechanisms underlying these observations are not settled; we suggest that prolonged inhibition of the hypothalamic-pituitary-gonadal axis by exercise, together with or because of the metabolic effects of dieting, is responsible for them.


Subject(s)
Growth/physiology , Gymnastics/physiology , Puberty/physiology , Adolescent , Age Determination by Skeleton , Age Factors , Body Height , Child , Female , Follow-Up Studies , Humans , Leg/anatomy & histology , Menarche/physiology , Physical Education and Training , Prospective Studies , Swimming/physiology
15.
Int J Sports Med ; 13(1): 40-6, 1992 Jan.
Article in English | MEDLINE | ID: mdl-1544731

ABSTRACT

This study compared the acceptance of two beverages (5% carbohydrate) of distinct osmolarities (hypotonic, 180 mOsm/kg and isotonic, 295 mOsm/kg) during the usual training practice of 97 athletes. A quantitative sensory profile by independent tasters ensured that organoleptic recognition would be unlikely during the tests. Each drink was consumed ad libitum during 3 different training sessions, at home. At each session, a subjective appreciation of hedonic and post-ingestive physiological effects (6 criteria) was obtained by means of a questionnaire. At the end of the experiment, the athletes were asked to express a preference for one of the "six" drinks. More athletes (blindly) chose the isotonic compared to the hypotonic drink (p = 0.03). This difference was not due intrinsically to the drinks, which the subjects were unable to distinguish on any of the criteria, but was related to certain aspects of the consumer's characteristics. Both groups had different drinking practices: the subjects choosing the isotonic beverage drank less before (p = 0.001) and more during (p = 0.013) the exercise. Age, sex, dimensions or type of physical activity (i.e. endurance vs speed/strength disciplines) were unrelated to the preference, except perhaps the duration of habitual exercise (p less than 0.05). We concluded that athletes, although unable to distinguish a hypotonic from an isotonic drink, may have specific habits and/or personal characteristics prompting them to favour one of them.


Subject(s)
Beverages , Consumer Behavior , Exercise , Rehydration Solutions , Adult , Digestion , Female , Humans , Male , Osmolar Concentration , Thirst
16.
Eur J Clin Pharmacol ; 43(4): 399-403, 1992.
Article in English | MEDLINE | ID: mdl-1451720

ABSTRACT

The debrisoquine/sparteine-type polymorphism of drug oxidation and the polymorphism for acetylation are two common inherited variations in human drug metabolism. The phenotypes for hydroxylation and acetylation can be predicted be newly developed methods based on mutation-specific amplification of DNA by the polymerase chain reaction (PCR), which also allow for identification of heterozygous carriers of one mutant allele. In the present study, the results of genotyping of 81 healthy European volunteers were compared with the phenotype obtained by the classical biochemical approach using debrisoquine and caffeine as probe drugs. Genotyping correctly predicted all 73 extensive metabolisers (EMs) and 6 out of 8 poor metabolisers (PMs) of debrisoquine. All 48 rapid acetylators and 33 of 35 slow acetylators were predicted. Overall, the DNA analysis result matched the in vivo phenotype in 97.5% of individuals.


Subject(s)
Debrisoquin/metabolism , Polymorphism, Genetic/genetics , Sparteine/metabolism , Acetylation , Adult , Female , Gene Amplification , Genotype , Humans , Hydroxylation , Male , Middle Aged , Mutation , Phenotype , Polymerase Chain Reaction
17.
Contact Dermatitis ; 25(4): 230-6, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1839264

ABSTRACT

Nicotine in a transdermal therapeutic system (TTS) has been introduced recently to help people to stop smoking. 14 volunteers (10 male, 4 female) with a history of former adverse skin reactions to this device were investigated. Skin tests for contact urticaria and patch tests for contact allergy were done with the individual components of the TTS. Contact sensitization to nicotine was identified in 5 and to the TTS itself in 1 individual. Irritant reactions due to occlusion were present in 9 subjects. The optimal test agent and concentration for elucidating the adverse skin reaction was an aqueous solution of 10% nicotine base. Atopy, as diagnosed by history and skin prick tests to common inhalant allergens, and contact sensitization to standard patch test allergens, were each identified in 6 subjects. Nicotine should be added to the expanding list of transdermally delivered drugs which may elicit contact dermatitis.


Subject(s)
Dermatitis, Contact/etiology , Drug Eruptions/etiology , Nicotine/adverse effects , Administration, Cutaneous , Adult , Aged , Female , Humans , Male , Middle Aged , Patch Tests , Smoking Prevention
18.
J Cardiovasc Pharmacol ; 18(2): 175-81, 1991 Aug.
Article in English | MEDLINE | ID: mdl-1717776

ABSTRACT

The aim of the present study was to look for possible additive or synergistic effects of the combined oral administration of a single dose of an angiotensin converting enzyme (ACE) inhibitor, benazepril (10 mg) (B), and a long-acting vasodilator, cadralazine (5 mg) (C), on blood pressure, arterial parameters, and active plasma renin. The study was carried out in eight normotensive subjects according to a double-blind, randomized, placebo-controlled, crossover design. Blood pressure (BP), heart rate, humeral artery diameter (D), carotid-femoral pulse-wave velocity (PWV), finger-pulse ratio (FPR), and plasma active renin (PAR) were measured at baseline and every 2 h over 8 h. A significant treatment effect was observed for supine and tilted BP, FPR, PWV, and PAR. The largest decrease in supine systolic and diastolic BP was observed with the combination (10.0 +/- 6.9/7.2 +/- 3.7 mm Hg). Six hours after drug intake, the mean changes in FPR were 0.05 +/- 0.24 (P), -0.06 +/- 0.30 (C), 0.13 +/- 0.32 (B), and 0.28 +/- 0.34 (B + C), and the mean changes in PWV were 0.14 +/- 0.66 m/s (P), 0.09 +/- 0.54 m/s (C), -0.29 +/- 0.50 m/s (B), and -0.55 +/- 0.48 m/s (B + C). PAR was more markedly augmented with the combination of the two drugs (142 +/- 40 pg/ml) than with benazepril alone (90 +/- 62 pg/ml). It was concluded that a single noneffective dose of a vasodilator administered together with an ACE inhibitor in normotensives can lower blood pressure and increase arterial compliance and plasma active renin.


Subject(s)
Angiotensin-Converting Enzyme Inhibitors/pharmacology , Antihypertensive Agents/pharmacology , Benzazepines/pharmacology , Blood Pressure/drug effects , Heart Rate/drug effects , Pyridazines/pharmacology , Administration, Oral , Adult , Double-Blind Method , Drug Synergism , Humans , Male , Pilot Projects , Posture , Random Allocation , Renin/blood
19.
Schweiz Rundsch Med Prax ; 80(7): 145-50, 1991 Feb 12.
Article in German | MEDLINE | ID: mdl-2008547

ABSTRACT

To assess efficacy and tolerance of a transdermal nicotine system (TNS) as adjuvant to tobacco withdrawal, 112 young, nicotine-dependent cigarette smokers were treated for nine weeks with TNS (n = 56) or placebo (n = 56). Initial doses of nicotine (21 or 14 mg/24 h) were based on previous smoking habits and stepwise reduced to 7 mg/24 h if abstinence was achieved during medication. After treatment, 39.3% of the TNS users were abstinent versus 19.6% on placebo (p less than 0.05). The craving for cigarettes diminished steadily, but not more significantly on TNS medication. Tenseness, difficulty in concentration and feelings of hunger were consistently and in part significantly lessened in the TNS group. The other withdrawal symptoms were not influenced by TNS treatment. Nine-month follow-up cotinine-verified abstinence rates were 12.5% in the TNS and 3.6% in the placebo group (n. s.). Transient mild or moderate erythema at the application site appeared in 20% of the TNS and 6.3% of the placebo group, and 7.1% of the TNS users dropped out because of severe localized erythema. Other mild, transient, systemic side effects reported by 33.9% of the TNS and 26.8% of the placebo users (n. s.) did not lead to drop-outs.


Subject(s)
Nicotine/administration & dosage , Smoking/drug therapy , Administration, Cutaneous , Adult , Carbon Monoxide/analysis , Double-Blind Method , Female , Humans , Male , Substance Withdrawal Syndrome
20.
Med Sci Sports Exerc ; 23(1): 115-22, 1991 Jan.
Article in English | MEDLINE | ID: mdl-1997805

ABSTRACT

To describe effects of past as well as current exercise, aerobic power, and subcutaneous fat on the serum lipid profile, two groups of former elite athletes (N = 27 runners, N = 9 bobsledders) and a control group of normal men (N = 23) were investigated. Analysis of variance indicated a significant effect of the type of sports activity on HDL cholesterol, apolipoprotein A-I, and triglyceride levels and on the LDL/HDL cholesterol and apolipoprotein B/A-I ratios, with the most favorable values seen in runners and the least favorable values seen in controls. Of the 27 former elite runners, one third (N = 9) had given up or strongly reduced training. This subgroup showed the steepest 15-yr decrease (from 1973 to 1988) in maximum aerobic power and the largest 15-yr increase in subcutaneous fat, and the lipid profile (measured in 1988) corresponded more to the one of bobsledders and controls than to the one of runners who had remained active. Separate correlational analyses of all runners (N = 27) and nonrunners (N = 32) showed that, in both cohorts, i) the 1988 measurements of exercise, aerobic power, and subcutaneous fat were more predictive for the lipid profile in 1988 than the corresponding 1973 values, ii) anthropometric characteristics, especially abdominal fat, had a stronger relation with serum lipid concentrations than exercise and aerobic power, and iii) 15-yr changes in anthropometric characteristics were, but 15-yr changes in exercise and aerobic power were not, associated with triglyceride, lipoprotein, and apolipoprotein levels in 1988.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Abdomen/anatomy & histology , Adipose Tissue/anatomy & histology , Exercise/physiology , Lipids/blood , Oxygen Consumption , Physical Fitness/physiology , Adult , Analysis of Variance , Cross-Sectional Studies , Humans , Life Style , Male , Time Factors , Track and Field
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