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Purpose: Childhood lymphoma survivors (CLSs) are at high risk of reduced daily activity. This work studied metabolic substrate use and cardiorespiratory function in response to exercise in CLSs. Methods: Twenty CLSs and 20 healthy adult controls matched for sex, age, and BMI took an incremental submaximal exercise test to determine fat/carbohydrate oxidation rates. Resting echocardiography and pulmonary functional tests were performed. Physical activity level, and blood metabolic and hormonal levels were measured. Results: CLSs reported more physical activity than controls (6317 ± 3815 vs. 4268 ± 4354 MET-minutes/week, p = 0.013), had higher resting heart rate (83 ± 14 vs. 71 ± 13 bpm, p = 0.006), and showed altered global longitudinal strain (− 17.5 ± 2.1 vs. − 19.8 ± 1.6%, p = 0.003). We observed no difference in maximal fat oxidation between the groups, but it was reached at lower relative exercise intensities in CLSs (Fatmax 17.4 ± 6.0 vs. 20.1 ± 4.1 mL/kg, p = 0.021). At V̇O2 peak, CLSs developed lower relative exercise power (3.2 ± 0.9 vs. 4.0 ± 0.7 W/kg, p = 0.012). Conclusion: CLSs reported higher levels of physical activity but they attained maximal fat oxidation at lower relative oxygen uptake and applied lower relative power at V̇O2 peak. CLSs may thus have lower muscular efficiency, causing greater fatigability in response to exercise, possibly related to chemotherapy exposure during adolescence and childhood. Long-term follow-up is essential and regular physical activity needs to be sustained. [ABSTRACT FROM AUTHOR]

This paper presents the numerical simulation and fabrication of a metasurface composed of silver nanorings with a split-ring gap. These nanostructures can exhibit optically-induced magnetic responses with unique possibilities to control absorption at optical frequencies. The absorption coefficient of the silver nanoring was optimized by performing a parametric study with Finite Difference Time Domain (FDTD) simulations. The absorption and scattering cross sections of the nanostructures are numerically calculated to assess the impact of the inner and outer radii, the thickness and the split-ring gap of one nanoring, as well as the periodicity factor for a group of four nanorings. This showed full control on resonance peaks and absorption enhancement in the near infrared spectral range. The experimental fabrication of this metasurface made of an array of silver nanorings is achieved by e-beam lithography and metallization. Optical characterizations are then carried out and compared to the numerical simulations. In contrast to usual microwave split-ring resonator metasurfaces reported in literature, the present study shows both the realization by a top-down process and modelling performed in the infrared frequency range. [ABSTRACT FROM AUTHOR]

The ability to produce muscle power during sprint acceleration is a major determinant of physical performance. The comparison of the force–velocity (F–v: theoretical maximal force, F0; velocity, v0 and maximal power output, Pmax) profile between men and women has attracted little attention. Most studies of sex differences have failed to apply a scaling ratio when reporting data. The present study investigated the sex effect on the F–v profile using an allometric model applied with body mass (BM), fat-free mass (FFM), fat-free mass of the lower limb (FFMLL), cross-sectional area (CSA) and leg length (LL) to mechanical parameters. Thirty students (15 men, 15 women) participated. Raw velocity–time data for three maximal 35 m sprints were measured with a radar. Mechanical parameters of the F–v relationship were calculated from the modelling of the velocity–time curve. When F0 and Pmax were allometrically scaled with BM (p = 0.538; ES = 0.23) and FFM (p = 0.176; ES = 0.51), there were no significant differences between men and women. However, when the allometric model was applied to Pmax with FFMLL (p = 0.015; ES = 0.52), F0 with CSA (p = 0.016; ES = 0.93) and v0 with LL (p ≤ 0.001; ES = 1.98) differences between men and women persisted. FFM explained 83% of the sex differences in the F–v profile (p ≤ 0.001). After applying an allometric model, sex differences in the F–v profile are explained by other factors than body dimensions (i.e., physiological qualitative differences). [ABSTRACT FROM AUTHOR]

Purpose: This work studied the acute effects in healthy adults of evening exercise timing on their quality of sleep and dietary intake over the following 12 h.Methods: Sixteen men and women, (age: 22.3 ± 1.4 years; BMI: 20.8 ± 1.4 kg/m2, intermediate chronotype) took part in three randomized crossover sessions spread over three consecutive weeks: control session (CTL), 1 h exercise session at 6:30 pm (E6:30) and 1 h exercise session at 8:30 pm (E8:30), in which exercise finished 4 h and 2 h before habitual bedtime, respectively. Exercise was an outdoor run at 60% HRmaxth. Energy expenditure and sleep were ambulatories monitored by accelerometry under free-living condition. Ad-libitum dinner and breakfast were used to measure subsequent energy intake and proportion of that energy derived from each macronutrient.Results: Evening exercise did not disrupt sleep. Improvement in sleep quality compared to the control condition was observed only when exercise was performed 4 h before habitual bedtime (WASO: p < 0.01; SE: p < 0.02). Interestingly, our results give insight into differences in sleep parameters response to evening exercise between habitually poor and good sleepers mainly when it comes to sleep efficiency and wake after sleep onset (all p < 0.01). There was no difference in calorie intake from ad-libitum dinner and breakfast. However, an association between improvement in sleep efficiency from acute exercise and reduction of energy intake the following morning was found.Conclusion: Early evening exercise could offer a useful alternative for achieving better sleep in healthy young adults especially when it comes to poor sleepers. [ABSTRACT FROM AUTHOR]

The effect of exercise on sleep remains controversial in athletes especially in junior athletes. This study tested the acute effect of additional intense rugby training on sleep, next-day dietary intake, and physical performances in adolescent rugby players compared to a day with regular exercise. 17 male rugby players in the national under-17 category (age: 15.7 ± 1.1 years, height: 1.78 ± 0.1 m, weight: 84.4 ± 13.6 kg, BMI: 26.6 ± 3.8 kg/m2, fat mass: 14.5 ± 3.4%, VO2max Yo-Yo test: 52.1 ± 4.4 mL/min/kg, evening chronotype) took part in this study. The athletes completed two 36-h experimental sessions in random order: a regular exercise program (REP) vs. an intensified exercise program (IEP) at a 1-week interval. Physical activity and sleep data were collected using accelerometers. Performance tests were conducted the next morning after an ad libitum breakfast. Sleep improved during intensive training (TST: + 26 min, SL: - 4%, WASO: - 39%, SE: + 8.5%) with moderate effect size. There was no next-day difference in calorie intake from breakfast, but macronutrient composition shifted toward proteins (regular: 15.4 ± 6.1% vs. intensive: 18.9 ± 7.4%, ES = - 0.650 [- 1.13;  - 0.18]). There were no significant differences in Wingate test performance or spatial awareness task time. However, performance in submaximal tests improved. Acute intensified training results in increased sleep duration and quality without disturbing next-day performance or dietary intake in young rugby players. [ABSTRACT FROM AUTHOR]

This work presents investigations about the realization and modelization of rectenna solar cells. Rectennas are antennas coupled with a rectifier to convert the alternative current originating from the antenna into direct current that can be harvested and stored. By reducing the size of the antennas to the nanoscale, interactions with visible and near-infrared light become possible. If techniques such as nanoimprint lithography make possible the fabrication of sufficiently small plasmonic structures to act as optical antennas, the concept of rectenna still faces several challenges. One of the most critical point is to achieve rectification at optical frequencies. To address this matter, we propose to use molecular diodes (ferrocenyl-alkanethiol) that can be self-assembled on metallic surfaces such as gold or silver. In this paper, we present a basic rectenna theory as well as finite-difference time-domain (FDTD) optical simulations of plasmonic structures and experimental results of both nanoimprint fabrication of samples and characterizations by electron microscopy, Raman spectroscopy, and cyclic voltammetry techniques. [ABSTRACT FROM AUTHOR]

Few studies have investigated the impact of school-based physical activity interventions on anthropometric characteristics concomitantly with aerobic and anaerobic capacities in young children. The present study aimed to assess the effect of a 6-month physical activity program on body composition and physical fitness among primary schoolchildren. Four hundred fifty-seven children aged 6 to 10 years were randomly assigned to the intervention group (229 children) or observational group (228 children). Participants' height and weight were assessed, and obesity was determined using French reference curves for BMI. The sum of the four skinfolds and fat-free mass were determined. Ground tests were used to assess aerobic (20-m shuttle run test) and anaerobic (cycling peak power) fitness before and after a 6-month physical activity intervention. The anthropometric modifications obtained over the 6 months cannot be attributed to the intervention as the ANOVA revealed no group effect (intervention vs. group). However, anaerobic and aerobic fitness were significantly improved, thanks to the program in both lean and obese children. A 6-month school-based physical activity intervention in 6- to 10-year-old children did not yield positive anthropometric improvements, but appears effective in terms of aerobic and anaerobic physical fitness. Two physical activity sessions per week in addition to standard physical education classes in primary schoolchildren bring effective results for the prevention of childhood obesity. [ABSTRACT FROM AUTHOR]

We aimed to examine the interchangeability of techniques used to assess maximal oxygen consumption (VO2max) and maximal aerobic power (MAP) employed to express the maximal fat oxidation point in obese children and adolescents. Rate of fat oxidation were measured in 24 obese subjects (13.0 +/- 2.4 years; Body Mass Index 30.2 +/- 6.3 kg m(-2)) who performed a five 4-min stages submaximal incremental cycling exercise. A second cycling exercise was performed to measure VO2max. Results are those of the 20 children who achieved the criterion of RER (>1.02) to assess the attainment of VO2max. Although correlations between results obtained by different methods were strong, Bland-Altman plots showed little agreement between the maximal fat oxidation point expressed as a percentage of measured VO2max and as % VO2max estimated according to ACSM guidelines (underestimation : -5.9%) or using the predictive equations of Wasserman (-13.9%). Despite a mean underestimation of 1.4% several values were out of the limits of agreement when comparing measured MAP and Theoretical MAP. Estimations of VO2max lead to underestimations of the maximal fat oxidation point. [ABSTRACT FROM AUTHOR]

Few investigations have studied protein metabolism in children and adolescent athletes which makes difficult the assessment of daily recommended dietary protein allowances in this population. The problematic in paediatric competitors is the determination of additional protein needs resulting from intensive physical training. The aim of this investigation was to determine protein requirement in 14-year-old male adolescent soccer players. Healthy male adolescent soccer players (N = 11, 13.8 +/- 0.1 year) participated in a short term repeated nitrogen balance study. Diets were designed to provide proteins at three levels: 1.4, 1.2 and 1.0 g protein per kg body weight (BW). Nutrient and energy intakes were assessed from 4 day food records corresponding to 4 day training periods during 3 weeks. Urine was collected during four consecutive days and analysed for nitrogen. The nitrogen balances were calculated from mean daily protein intake, mean urinary nitrogen excretion and estimated faecal and integumental nitrogen losses. Nitrogen balance increased with both protein intake and energy balance. At energy equilibrium, the daily protein intake needed to balance nitrogen losses was 1.04 g kg(-1) day(-1). This corresponds to an estimated average requirement (EAR) for protein of 1.20 g kg(-1) day(-1) and a recommended daily allowance (RDA) of 1.40 g kg(-1) day(-1) assuming a daily nitrogen deposition of 11 mg kg(-1). The results of the present study suggest that the protein requirements of 14-year-old male athletes are above the RDA for non-active male adolescents. [ABSTRACT FROM AUTHOR]

A workshop sponsored by the Human Toxicology Project Consortium (HTPC), "Building Shared Experience to Advance Practical Application of Pathway-Based Toxicology: Liver Toxicity Mode-of-Action" brought together experts from a wide range of perspectives to inform the process of pathway development and to advance two prototype pathways initially developed by the European Commission Joint Research Center (JRC): liverspecific fibrosis and steatosis. The first half of the workshop focused on the theory and practice of pathway development; the second on liver disease and the two prototype pathways. Participants agreed pathway development is extremely useful for organizing information and found that focusing the theoretical discussion on a specific AOP is helpful. It is important to include several perspectives during pathway development, including information specialists, pathologists, human health and environmental risk assessors, and chemical and product manufacturers, to ensure the biology is well captured and end use is considered. [ABSTRACT FROM AUTHOR]

Skin function is not limited to a physical barrier. According to its total surface area, it is also considered as an extra-hepatic metabolizing organ. In vitro engineered human skins have been developed to replace limited ex vivo normal human skin samples (NHS). Thus, assessing and comparing skin models from SkinEthic [Episkin™, RHE™ and the full thickness model (FTM)] with NHS in terms of metabolic capability are essential. The apparent activities of main cutaneous isoforms of cytochrome P450-dependent monooxygenases (CYP1A1/1B1, 2B6/2C18/2E1, 3A5/3A7), esterase, glutathione- S-[(GST), A, M, P, T], N-acetyl-(NAT1), uridinyl-diphosphate glucuronyl-(UDPGT 1A family) and sulfo-(SULT1A1) transferases were determined using probe substrates. Mean activities indicative of CYP1A1/1B1 (expressed as pmol/mg protein/6 h) in RHE™ (2.8) and FTM (2.6) were very similar to NHS (3.0) while Episkin™ showed a higher activity (9.1). Activities of CYP3A5/3A7 in FTM (3.3) and Episkin™ (3.6) were similar to NHS (3.8) while activity in RHE™ (13.3) was higher. CYP2B6/2C18/2E1 activity was below LOQ (0.5) in all skin models and NHS. Comparable intrinsic metabolic clearances were measured between NHS and skin models for esterase, UDPGT, GST and NAT1 activities. SULT1A1 activity toward probe substrates was not detected in skin models and observed at the limit of detection in NHS. Weak cytochrome P450-dependent monooxygenases, high esterase and transferase activities suggested that NHS and skin models exhibited limited functionalization and much greater detoxification (hydrolytic and conjugating) capacities. These results demonstrate that skin models are similar to NHS in terms of metabolic functionality toward xenobiotics investigated and useful tools to assess both the local efficiency and safety of cosmetics. [ABSTRACT FROM AUTHOR]

The imbalance between energy expenditure and energy intake is the main factor accounting for the progression of obesity. For many years, physical activity has been part of weight-loss programmes to increase energy expenditure. It is now recognized that exercise can also affect appetite and energy consumption. In the context of seeking new obesity treatments, it is of major interest to clarify the impact of physical exercise on energy intake. Many reviews on this topic have been published regarding both lean and overweight adults, and this review focuses on the relationships between acute exercise and the short-term regulation of energy intake in lean and overweight or obese youths. The current literature provides very few data regarding the impact of exercise on subsequent energy intake and perceived and measured appetite in children and adolescents, mainly because of methodological difficulties in the assessment of both energy intake and expenditure. It has been long suggested that energy intake was regulated after exercise in order to compensate for the exercise-induced energy expenditure and then preserve energy balance. This overview underlines that the energy expended during exercise is not the main parameter that influences subsequent energy intake in both lean and overweight/obese children and adolescents, and that factors such as the duration or intensity of exercise may have larger impact. The effects of acute exercise on the following nutritional adaptations (energy intake and appetite feelings) remain inconclusive in lean youths, mainly due to the lack of data and the disparity of the methodologies used. Studies in overweight or obese children and adolescents are confronted with the same difficulties, and the few available data suggest that intensive exercise (>70% maximal oxygen consumption) can induce a reduction in daily energy balance, as a result of its anorexigenic effect in obese adolescents. However, further studies are needed to clarify the impact of acute exercise on subsequent nutritional adaptations and appetite-related hormones in children and adolescents, and to investigate the effect of chronic exercise programmes. [ABSTRACT FROM AUTHOR]

During exercise, substrate utilization plays a major role in performance and disease prevention. The contribution of fat and carbohydrates to energy expenditure during exercise is modulated by several factors, including intensity and duration of exercise, age, training and diet, but also gender. Because sex hormone levels change throughout a woman's lifetime (in connection with puberty, the menstrual cycle, use of oral contraceptives and menopause), the female population has to be considered specifically in terms of substrate utilization, and metabolic and hormonal responses to exercise. Before puberty, there is no difference between males and females when it comes to substrate oxidation during exercise. This is not the case during adulthood, since women are known to rely more on fat than men for the same relative intensity of exercise. Among adult women, the menstrual cycle and use of oral contraceptives may influence substrate oxidation. While some authors have noted that the luteal phase of the menstrual cycle is connected with greater lipid oxidation, compared with the follicular stage, other authors have found no difference. Among oral contraceptive users, fat oxidation is sometimes increased during prolonged exercise with a concomitant rise in lipolytic hormones, as well as growth hormone. If this result is not always observed, the type of oral contraceptive (monophasic vs triphasic) and hormone doses may be implicated. Menopause represents a hormonal transition in a woman's life, leading to a decline in ovarian hormone production. A decrease in fat oxidation is consequently observed, and some studies have demonstrated a similar respiratory exchange ratio during prolonged exercise in postmenopausal women and in men. As is the case during puberty, no sex difference should thus appear after menopause in the absence of hormonal replacement therapy (HRT). Results concerning women who take HRT remain conflicting. HRT may act on fat loss by increasing lipid metabolism, but this depends on how the treatment is administered (orally vs transdermally). To better understand the role of ovarian hormones in substrate oxidation, studies have made use of animal protocols to investigate cellular mechanisms. Estradiol and progesterone seem to have opposite effects, with greater lipid oxidation when estradiol is used alone. However, the concentrations used (physiological levels or pharmacological doses) may considerab1y modify fuel selection. In cases where conflicting data are observed in studies of substrate utilization and prolonged exercise in women, methodological reasons must be called into question. Too many parameters, which oftentimes are not specified, may modulate substrate utilization and metabolic and hormonal responses to prolonged exercise. Although information is generally provided about the type of exercise, its duration and the subjects' training level, detailed information is not always given about the subjects' nutritionalstate and, more specifically, the hormonal status of female subjects. The primary purpose of this review was to identify the impact of hormonal status on substrate oxidation among female subjects at rest and during exercise. A second aim was to describe gender differences in substrate utilization during exercise. [ABSTRACT FROM AUTHOR]

Children are able to resist fatigue better than adults during one or several repeated high-intensity exercise bouts. This finding has been reported by measuring mechanical force or power output profiles during sustained isometric maximal contractions or repeated bouts of high-intensity dynamic exercises. The ability of children to better maintain performance during repeated high-intensity exercise bouts could be related to their lower level of fatigue during exercise and/or faster recovery following exercise. This may be explained by muscle characteristics of children, which are quantitatively and qualitatively different to those of adults. Children have less muscle mass than adults and hence, generate lower absolute power during high-intensity exercise. Some researchers also showed that children were equipped better for oxidative than glycolytic pathways during exercise, which would lead to a lower accumulation of muscle by-products. Furthermore, some reports indicated that the lower ability of children to activate their type II muscle fibres would also explain their greater resistance to fatigue during sustained maximal contractions. The lower accumulation of muscle by-products observed in children may be suggestive of a reduced metabolic signal, which induces lower ratings of perceived exertion. Factors such as faster phosphocreatine resynthesis, greater oxidative capacity, better acid-base regulation, faster readjustment of initial cardiorespiratory parameters and higher removal of metabolic by-products in children could also explain their faster recovery following high-intensity exercise. From a clinical point of view, muscle fatigue profiles are different between healthy children and children with muscle and metabolic diseases. Studies of dystrophic muscles in children indicated contradictory findings of changes in contractile properties and the muscle fatigability. Some have found that the muscle of boys with Duchenne muscular dystrophy (DMD) fatigued less than that of healthy boys, but others have reported that the fatigue in DMD and in normal muscle was the same. Children with glycogenosis type V and VII and dermatomyositis, and obese children tolerate exercise weakly and show an early fatigue. Studies that have investigated the fatigability in children with cerebral palsy have indicated that the femoris quadriceps was less fatigable than that of a control group but the fatigability of the triceps surae was the same between the two groups. Further studies are required to elucidate the mechanisms explaining the origins of muscle fatigue in healthy and diseased children. The use of non-invasive measurement tools such as magnetic resonance imaging and magnetic resonance spectroscopy in paediatric exercise science will give researchers more insight in the future. [ABSTRACT FROM AUTHOR]

OBJECTIVE:: To determine the longitudinal changes in body composition, physical capacities, and time and energy expenditure (EE) devoted to various activities in the course of a 9-month weight-reduction period. DESIGN:: Longitudinal, clinical intervention including lifestyle education, moderate energy restriction, progressive training, and psychological follow-up. SUBJECTS:: A total of 27 (13 boys and 14 girls) severely obese adolescents (mean BMI: 33.9?kg/m2; 41.5%fat mass (FM)), aged 12-16?y. MEASUREMENTS:: Before the beginning and after the weight-reduction program, body composition was assessed by dual-energy X-ray absorptiometry (DXA), physical capacities by multistage treadmill test, and EE both by whole-body calorimetry and in free-living conditions using the heart rate-recording method. During 8 months of the weight-reduction period, type and duration of each activity were recorded using a daily controlled activity diary. RESULTS:: One boy resigned after 5 months. Body weight (BW) and FM decreased (-19 and-42%, respectively, P<0.001) both in boys and in girls, but fat-free mass (FFM) decreased only in girls (-6%, P<0.001). VO2max (l/min) did not vary significantly, but strength and fitness were improved (P<0.001). Time and EE spent at sedentary activities decreased significantly (P<0.001) to the benefit of moderate (recreational) activities and total physical activities (P<0.001) at the institution during the weekdays, and at home during the weekends and holidays. CONCLUSION:: The great BW and FM losses, preservation of FFM, and improvement of physical capacities of obese adolescents obtained under experimental conditions were associated with increases in leisure physical activities in free-living conditions at the expense of sleep and sedentary activities.International Journal of Obesity (2005) 29, 37-46. doi:10.1038/sj.ijo.0802845 Published online 9 November 2004 [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare physiological data obtained during cycling using a noncircular "Harmonic" chainring versus a standard circular chainring over a range of speeds and slopes in endurance-trained cyclists. Thirteen male subnational cyclists (16-45 years) performed two maximal graded exercises on their own bicycle: one with a circular chainring, the other with a Harmonic chainring with the same gearwheel (52 teeth). The two chainrings were randomly assigned to avoid learning effects. The tests were carried out on a simulator. Speeds and/or slopes were increased every 2 min 30 s until exhaustion of the subject. Ventilation, oxygen uptake, carbon dioxide output, respiratory exchange ratio, and heart rate were continuously measured during the tests. Blood lactate concentration was measured during the last 30 s of each level. No significant difference was observed in any of the submaximal parameters measured during the tests ( P>0.05). Similarly, maximal values were not statistically different ( P>0.05). In conclusion, although the design of the Harmonic chainring was based on optimization analysis, comparison of the physiological response in this study did not translate into an advantage of the Harmonic over circular chainring during submaximal and maximal pedaling in trained cyclists. [ABSTRACT FROM AUTHOR]

The aim of the present study was to compare physiological data obtained during cycling using a noncircular "Harmonic" chainring versus a standard circular chainring over a range of speeds and slopes in endurance-trained cyclists. Thirteen male subnational cyclists (16?45 years) performed two maximal graded exercises on their own bicycle: one with a circular chainring, the other with a Harmonic chainring with the same gearwheel (52 teeth). The two chainrings were randomly assigned to avoid learning effects. The tests were carried out on a simulator. Speeds and/or slopes were increased every 2 min 30 s until exhaustion of the subject. Ventilation, oxygen uptake, carbon dioxide output, respiratory exchange ratio, and heart rate were continuously measured during the tests. Blood lactate concentration was measured during the last 30 s of each level. No significant difference was observed in any of the submaximal parameters measured during the tests ( P>0.05). Similarly, maximal values were not statistically different ( P>0.05). In conclusion, although the design of the Harmonic chainring was based on optimization analysis, comparison of the physiological response in this study did not translate into an advantage of the Harmonic over circular chainring during submaximal and maximal pedaling in trained cyclists. [ABSTRACT FROM AUTHOR]

The binding of CPT-11 and SN-38 to human plasma proteinswas studied by ultrafiltration at 37°C and pH 7.4. In plasma,CPT-11 was 66–60% bound in the range 100–4000ng/ml and SN-38 was 94–96% bound in the range50–200 ng/ml. At these concentrations the plasma bindingof CPT-11 was slightly saturable, but the plasma binding of SN-38was concentration-independent. Albumin was the main carrier ofCPT-11 and SN-38 in plasma. In blood, the binding of CPT-11 wasmoderate (80%), mainly to plasma proteins (47%) anderythrocytes (33%). The binding of SN-38 was high(99%) and most of SN-38 in blood was located in bloodcells (approximately 66%) The simulation of a grade 3hematotoxicity (according to National Cancer Institute's CommonToxicity Criteria grading) on the SN-38 blood distributionyielded an increase in fu (free fraction of drug in plasma) from1.05 to 2.08 and a decrease in CBl/CP from1.66 to 1.14 (both resulting from a decreased cellbinding). [ABSTRACT FROM AUTHOR]

This study was designed to investigate in the saliva the influence in female athletes of handball or volleyball training on concentrations of cortisol [C], dehydroepiandrosterone [DHEA], and on the [DHEA]:[C] ratio over 16 weeks of training. Data were compared to those of sedentary women. Saliva samples were collected upon waking after an overnight fast during the 1st week (W1) of the training programme and in the 16th week (W16). The training programme increased the resting concentrations of saliva [DHEA] in all the sportswomen. In contrast, a decrease of [DHEA] was noted in the sedentary group (W16 < W1; P < 0.05). In none of the women did the [C] at rest change significantly during the study. Between W1 and W16, the [DHEA]:[C] ratio increased by more than 30% in all the sportswomen. In addition, the athletes with the highest performance levels and greatest amount of training had the lowest [DHEA]:[C] ratio. Negative linear relationships between the amount of training and the [DHEA]:[C] ratio were found both at W1 ( r = −0.53 P < 0.001), and W16 ( r=−0.73 P < 0.001), suggesting that the latter could be used as an indicator of the training status of sportswomen. [ABSTRACT FROM AUTHOR]

In a group of 20 elite female handball or volleyball players, an evaluation was made of the response to a 4-month training period of cortisol, androstenedione and dehydroepiandrosterone in the saliva. At the beginning of the training programme (W1) and at the 7th (W7) and 16th weeks (W16), hormone concentrations were measured on awakening (8 a.m.; resting samples), and also before ( t0) and at the end ( t120) of a 2-h exercise session (simulated match) which took place at 6 p.m. The training programme increased the concentrations of adrenal androgens in the saliva at rest ( P<0.05) for both groups of subjects, with no change being noted in cortisol concentrations. In contrast, amongst the volleyball players, stressful stimuli produced by an increase in the amount of training did not affect adrenocortical metabolism during exercise. Indeed, a simulated volleyball match resulted in a decrease in salivary cortisol ( P<0.05) and androgen concentrations ( P<0.05) without regard for the week chosen for the test investigations. In contrast, a simulated handball match caused an increase in cortisol concentrations at W1 only ( P<0.05), with no change in the adrenal androgens concentration in any week of the training programme. The regulators of these hormones during a period of exercise and during the course of a training programme would seem to be different. [ABSTRACT FROM AUTHOR]

Adverse long-term cardiovascular (CV) consequences of PE are well established in women. However, the mechanism responsible for that risk remains unknown. Here, we mated wild-type female mice of the FVB/N strain to STOX1A-overexpressing mice to mimic severe PE and investigated the long-term consequences on the maternal cardiovascular system. Ultrasonography parameters were analyzed in mice before pregnancy and at 3 and 6 months post-pregnancy. At 6 months post-pregnancy, cardiac stress test induced by dobutamine injection revealed an abnormal ultrasonography Doppler profile in mice with previous PE. Eight months post-pregnancy, the heart, endothelial cells (ECs) and plasma of females were analyzed and compared to controls. The heart of mice with PE showed left-ventricular hypertrophy associated with altered histology (fibrosis). Transcriptomic analysis revealed the deregulation of 1149 genes in purified ECs and of 165 genes in the hearts, many being involved in heart hypertrophy. In ECs, the upregulated genes were associated with inflammation and cellular stress. Systems biology analysis identified interleukin 6 (IL-6) as a hub gene connecting these pathways. Plasma profiling of 33 cytokines showed that, 8 of them (Cxcl13, Cxcl16, Cxcl11, IL-16, IL-10, IL-2, IL-4 and Ccl1) allowed to discriminate mice with previous PE from controls. Thus, PE triggers female long-term CV consequences on the STOX1 mouse model. [ABSTRACT FROM AUTHOR]