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Sample records for exerts differential physiological

  1. Growth temperature exerts differential physiological and transcriptional responses in laboratory and wine strains of Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Pizarra, Francisco J.; Jewett, Michael Christopher; Nielsen, Jens

    2008-01-01

    Laboratory strains of Saccharomyces cerevisiae have been widely used as a model for studying eukaryotic cells and mapping the molecular mechanisms of many different human diseases. Industrial wine yeasts, on the other hand, have been selected on the basis of their adaptation to stringent...... global insight into how growth temperature affects differential physiological and transcriptional responses in laboratory and wine strains of S. cerevisiae....... environmental conditions and the organoleptic properties that they confer to wine. Here, we used a two-factor design to study the responses of a standard laboratory strain, CEN.PK113-7D, and an industrial wine yeast strain, EC1118, to growth temperatures of 15 degrees C and 30 degrees C in nitrogen...

  2. Physiological and Perceived Exertion Responses during International Karate Kumite Competition

    Science.gov (United States)

    Tabben, Montassar; Sioud, Rim; Haddad, Monoem; Franchini, Emerson; Chaouachi, Anis; Coquart, Jeremy; Chaabane, Helmi; Chamari, Karim; Tourny-Chollet, Claire

    2013-01-01

    Purpose Investigate the physiological responses and rating of perceived exertion (RPE) in elite karate athletes and examine the relationship between a subjective method (Session-RPE) and two objective heart-rate (HR)-based methods to quantify training-load (TL) during international karate competition. Methods Eleven karatekas took part in this study, but only data from seven athletes who completed three matches in an international tournament were used (four men and three women). The duration of combat was 3 min for men and 2 min for women, with 33.6±7.6 min for the first interval period (match 1–2) and 14.5±3.1 min for the second interval period (match 2–3). HR was continuously recorded during each combat. Blood lactate [La-] and (RPE) were measured just before the first match and immediately after each match. Results Means total fights time, HR, %HRmax, [La-], and session-RPE were 4.7±1.6 min, 182±9 bpm, 91±3%, 9.02±2.12 mmol.L-1 and 4.2±1.2, respectively. No significant differences in %HRmax, [La-], and RPE were noticed across combats. Significant correlations were observed between RPE and both resting HR (r=0.60; P=0.004) and mean HR (r=0.64; P=0.02), session-RPE and Banister training-impulse (TRIMP) (r=0.84; Pkarate competition elicited near-maximal cardiovascular responses and high [La-]. Training should therefore include exercise bouts that sufficiently stimulate the zone between 90 and 100% HRmax. Karate coaches could use the RPE-method to follow competitor's competition loads and consider it in their technical and tactical training. PMID:24800001

  3. Exertional dyspnea in mitochondrial myopathy: clinical features and physiological mechanisms.

    Science.gov (United States)

    Heinicke, Katja; Taivassalo, Tanja; Wyrick, Phil; Wood, Helen; Babb, Tony G; Haller, Ronald G

    2011-10-01

    Exertional dyspnea limits exercise in some mitochondrial myopathy (MM) patients, but the clinical features of this syndrome are poorly defined, and its underlying mechanism is unknown. We evaluated ventilation and arterial blood gases during cycle exercise and recovery in five MM patients with exertional dyspnea and genetically defined mitochondrial defects, and in four control subjects (C). Patient ventilation was normal at rest. During exercise, MM patients had low Vo(2peak) (28 ± 9% of predicted) and exaggerated systemic O(2) delivery relative to O(2) utilization (i.e., a hyperkinetic circulation). High perceived breathing effort in patients was associated with exaggerated ventilation relative to metabolic rate with high VE/VO(2peak), (MM = 104 ± 18; C = 42 ± 8, P ≤ 0.001), and Ve/VCO(2peak)(,) (MM = 54 ± 9; C = 34 ± 7, P ≤ 0.01); a steeper slope of increase in ΔVE/ΔVCO(2) (MM = 50.0 ± 6.9; C = 32.2 ± 6.6, P ≤ 0.01); and elevated peak respiratory exchange ratio (RER), (MM = 1.95 ± 0.31, C = 1.25 ± 0.03, P ≤ 0.01). Arterial lactate was higher in MM patients, and evidence for ventilatory compensation to metabolic acidosis included lower Pa(CO(2)) and standard bicarbonate. However, during 5 min of recovery, despite a further fall in arterial pH and lactate elevation, ventilation in MM rapidly normalized. These data indicate that exertional dyspnea in MM is attributable to mitochondrial defects that severely impair muscle oxidative phosphorylation and result in a hyperkinetic circulation in exercise. Exaggerated exercise ventilation is indicated by markedly elevated VE/VO(2), VE/VCO(2), and RER. While lactic acidosis likely contributes to exercise hyperventilation, the fact that ventilation normalizes during recovery from exercise despite increasing metabolic acidosis strongly indicates that additional, exercise-specific mechanisms are responsible for this distinctive pattern of exercise ventilation.

  4. Physiological responses and perceived exertion during cycling with superimposed electromyostimulation.

    Science.gov (United States)

    Wahl, Patrick; Schaerk, Jonas; Achtzehn, Silvia; Kleinöder, Heinz; Bloch, Wilhelm; Mester, Joachim

    2012-09-01

    The goal of the study was to evaluate and to quantify the effects of local electromyostimulation (EMS) during cycling on the cardiorespiratory system, muscle metabolism, and perceived exertion compared with cycling with no EMS. Ten healthy men (age: 24.6 ± 3.2 years, V[Combining Dot Above]O2max: 54.1 ± 6.0 ml·min·kg) performed 3 incremental cycle ergometer step tests, 1 without and 2 with EMS (30 and 85 Hz) until volitional exhaustion. Lactate values and respiratory exchange ratio were significantly higher at intensities ≥75% peak power output (PPO) when EMS was applied. Bicarbonate concentration, base excess (BE), and Pco2 were significantly lower when EMS was applied compared with the control at intensities ≥75% PPO. Saliva cortisol levels increased because of the exercise but were unaffected by EMS. Furthermore, EMS showed greater effects on CK levels 24 hours postexercise than normal cycling did. Rating of perceived exertion was significantly higher at 100% PPO with EMS. No statistical differences were found for heart rate, pH, and Po2 between the tested cycling modes. The main findings of this study are greater metabolic changes (lactate, respiratory exchange ratio, BE, (Equation is included in full-text article.), Pco2) during cycling with EMS compared with normal cycling independent of frequency, mainly visible at higher work rates. Because metabolic alterations are important for the induction of cellular signaling cascades and adaptations, these results lead to the hypothesis that applied EMS stimulations during cycling exercise might be an enhancing stimulus for skeletal muscle metabolism and related adaptations. Thus, superimposed EMS application during cycling could be beneficial to aerobic performance enhancements in athletes and in patients who cannot perform high workloads. However, the higher demand on skeletal muscles involved must be considered.

  5. Dehydroepiandrosterone exerts antiglucocorticoid action on human preadipocyte proliferation, differentiation, and glucose uptake

    Science.gov (United States)

    McNelis, Joanne C.; Manolopoulos, Konstantinos N.; Gathercole, Laura L.; Bujalska, Iwona J.; Stewart, Paul M.; Tomlinson, Jeremy W.

    2013-01-01

    Glucocorticoids increase adipocyte proliferation and differentiation, a process underpinned by the local reactivation of inactive cortisone to active cortisol within adipocytes catalyzed by 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1). The adrenal sex steroid precursor dehydroepiandrosterone (DHEA) has been shown to inhibit 11β-HSD1 in murine adipocytes; however, rodent adrenals do not produce DHEA physiologically. Here, we aimed to determine the effects and underlying mechanisms of the potential antiglucocorticoid action of DHEA and its sulfate ester DHEAS in human preadipocytes. Utilizing a human subcutaneous preadipocyte cell line, Chub-S7, we examined the metabolism and effects of DHEA in human adipocytes, including adipocyte proliferation, differentiation, 11β-HSD1 expression, and activity and glucose uptake. DHEA, but not DHEAS, significantly inhibited preadipocyte proliferation via cell cycle arrest in the G1 phase independent of sex steroid and glucocorticoid receptor activation. 11β-HSD1 oxoreductase activity in differentiated adipocytes was inhibited by DHEA. DHEA coincubated with cortisone significantly inhibited preadipocyte differentiation, which was assessed by the expression of markers of early (LPL) and terminal (G3PDH) adipocyte differentiation. Coincubation with cortisol, negating the requirement for 11β-HSD1 oxoreductase activity, diminished the inhibitory effect of DHEA. Further consistent with glucocorticoid-opposing effects of DHEA, insulin-independent glucose uptake was significantly enhanced by DHEA treatment. DHEA increases basal glucose uptake and inhibits human preadipocyte proliferation and differentiation, thereby exerting an antiglucocorticoid action. DHEA inhibition of the amplification of glucocorticoid action mediated by 11β-HSD1 contributes to the inhibitory effect of DHEA on human preadipocyte differentiation. PMID:24022868

  6. Physiological mechanisms of sex differences in exertional dyspnoea: role of neural respiratory motor drive.

    Science.gov (United States)

    Schaeffer, Michele R; Mendonca, Cassandra T; Levangie, Marc C; Andersen, Ross E; Taivassalo, Tanja; Jensen, Dennis

    2014-02-01

    What is the central question of this study? Does the combination of a higher neural respiratory drive and greater dynamic mechanical ventilatory constraints during exercise in healthy women versus men form the mechanistic basis of sex differences in activity-related dyspnoea? What is the main finding and its importance? Sex differences in activity-related dyspnoea in health primarily reflected the awareness of a higher neural respiratory drive needed to achieve any given ventilation during exercise in the setting of relatively greater dynamic mechanical ventilatory constraints in women. These findings may have implications for our understanding of the mechanisms of sex differences in exertional dyspnoea in variants of health (e.g. the elderly) and in patients with cardiorespiratory disease. The purpose of this study was to elucidate the physiological mechanisms of sex differences in exertional dyspnoea. We compared detailed measures of neural respiratory motor drive [diaphragmatic EMG (EMGdi) expressed as a percentage of maximal EMGdi (EMGdi%max)], breathing pattern, operating lung volumes, dynamic respiratory mechanics [tidal oesophageal (P(oes,tida)l%peak) and transdiaphragmatic pressure swings (P(di,tidal)%peak) expressed as a percentage of their respective peak values] and sensory intensity and unpleasantness ratings of dyspnoea during symptom-limited incremental cycle exercise in healthy young women (n = 25) and men (n = 25). The tidal volume to forced vital capacity ratio (V(T)%FVC), breathing frequency, EMGdi%max, P(oes,tidal)%peak, P(di,tidal)%peak and sensory intensity and unpleasantness ratings of dyspnoea were higher, while dynamic inspiratory capacity and inspiratory reserve volume were lower at a standardized absolute ventilation of 55 l min(-1) during submaximal exercise in women versus men (all P sex had no demonstrable effect on the inter-relationships between exercise-induced increases in V(T)%FVC, EMGdi%max and sensory intensity and unpleasantness

  7. Exertional Dyspnoea in Chronic Respiratory Diseases: From Physiology to Clinical Application.

    Science.gov (United States)

    Dubé, Bruno-Pierre; Vermeulen, François; Laveneziana, Pierantonio

    2017-02-01

    Dyspnoea is a complex, highly personalized and multidimensional sensory experience, and its underlying cause and mechanisms are still being investigated. Exertional dyspnoea is one of the most frequently encountered symptoms of patients with cardiopulmonary diseases, and is a common reason for seeking medical help. As the symptom usually progresses with the underlying disease, it can lead to an avoidance of physical activity, peripheral muscle deconditioning and decreased quality of life. Dyspnoea is closely associated with quality of life, exercise (in)tolerance and prognosis in various conditions, including chronic obstructive pulmonary disease, heart failure, interstitial lung disease and pulmonary hypertension, and is therefore an important therapeutic target. Effective management and treatment of dyspnoea is an important challenge for caregivers, and therapeutic options that attempt to reverse its underlying cause have been only partially successful This "review" will attempt to shed light on the physiological mechanisms underlying dyspnoea during exercise and to translate/apply them to a broad clinical spectrum of cardio-respiratory disorders. Copyright © 2016 SEPAR. Publicado por Elsevier España, S.L.U. All rights reserved.

  8. Gender differences in exerted forces and physiological load during pushing and pulling of wheeled cages by postal workers

    NARCIS (Netherlands)

    van der Beek, A. J.; Kluver, B. D.; Frings-Dresen, M. H.; Hoozemans, M. J.

    2000-01-01

    The aim was to determine gender differences regarding exerted forces and physiological load during push/pull tasks simulating the daily working practice of postal workers. Eight female and four male workers handled four-wheeled cages under eight conditions corresponding to the cage weight (130, 250,

  9. A detailed quantification of differential ratings of perceived exertion during team-sport training.

    Science.gov (United States)

    McLaren, Shaun J; Smith, Andrew; Spears, Iain R; Weston, Matthew

    2017-03-01

    To investigate the application of differential ratings of perceived exertion (dRPE) to team-sport training. Single cohort, observational study. Twenty-nine professional rugby union players were monitored over a six-week intensified training period. Training sessions were classified as: high-intensity intervals, repeated high-intensity efforts, speed, skill-based conditioning, skills, whole-body resistance, or upper-body resistance. After each session, players recorded a session rating of perceived exertion (sRPE; CR100 ® ), along with differential session ratings for breathlessness (sRPE-B), leg muscle exertion (sRPE-L), upper-body muscle exertion (sRPE-U), and cognitive/technical demands (sRPE-T). Each score was multiplied by the session duration to calculate session training loads. Data were analysed using mixed linear modelling and multiple linear regression, with magnitude-based inferences subsequently applied. Between-session differences in dRPE scores ranged from very likely trivial to most likely extremely large and within-session differences amongst dRPE scores ranged from unclear to most likely very large. Differential RPE training loads combined to explain 66-91% of the variance in sRPE training loads, and the strongest associations with sRPE training load were with sRPE-L for high-intensity intervals (r=0.67; 90% confidence limits ±0.22), sRPE-B for repeated high-intensity efforts (0.89; ±0.08) and skill-based conditioning (0.67; ±0.19), sRPE-T for Speed (0.63; ±0.17) and Skills (0.51; ±0.28), and sRPE-U for resistance training (whole-body: 0.61; ±0.21, upper-body: 0.92; ±0.07). Differential RPE can provide a detailed quantification of internal load during training activities commonplace in team sports. Knowledge of the relationships between dRPE and sRPE can isolate the specific perceptual demands of different training modes. Copyright © 2016 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  10. The application of differential ratings of perceived exertion to Australian Football League matches.

    Science.gov (United States)

    Weston, Matthew; Siegler, Jason; Bahnert, Andrew; McBrien, James; Lovell, Ric

    2015-11-01

    To investigate the application of differential ratings of perceived exertion for the examination of internal load during Australian Football League (AFL) matches. Single cohort, observational study. Using the centiMax rating of perceived exertion (RPE) scale, 26 professional AFL players provided ratings for match exertion (RPE-M), along with differential ratings for breathlessness (RPE-B), leg exertion (RPE-L), and technical demand (RPE-T) following 129 matches (5.0 ± 1.6 matches per player). Global positioning satellite (GPS) and accelerometer measures were also collected. Data were analysed using magnitude-based inferences. RPE scores were 93.0 ± 8.2 AU (RPE-M), 89.0 ± 11.0 AU (RPE-B), 91.5 ± 9.8 AU (RPE-L), and 87.0 ± 10.0 AU (RPE-T). There was a most likely small difference between RPE-L and RPE-T (5.5%; ± 90% confidence limits 1.9%), a likely small difference between RPE-L and RPE-B (3.5%; ± 1.5%) and a possibly small difference between RPE-B and RPE-T (1.9%; ± 1.9%). Within-player correlations between RPE and GPS measures were small for RPE-M (r = 0.14-0.28), unclear to small for RPE-B (r = 0.06-0.24) and unclear to moderate for RPE-L (r = 0.06-0.37). Differential RPE's combined to explain 76% of the variance in RPE-M. For all RPE scores, within-player variability was moderate to high (typical error: 7.9-12.4%), and the thresholds for a likely between-match change were 8.8-13.7%. As differential RPE's represent distinct sensory inputs, the collection of these scores facilitate the interpretation of internal match loads and therefore represent a valuable addition to match data collection procedures. Moderate to high within-player variability should be considered when interpreting between-match changes in all RPE scores. Copyright © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  11. Tryptophan promotes morphological and physiological differentiation in Streptomyces coelicolor.

    Science.gov (United States)

    Palazzotto, Emilia; Renzone, Giovanni; Fontana, Pietro; Botta, Luigi; Scaloni, Andrea; Puglia, Anna Maria; Gallo, Giuseppe

    2015-12-01

    The molecular mechanisms regulating tryptophan biosynthesis in actinomycetes are poorly understood; similarly, the possible roles of tryptophan in the differentiation program of microorganism life-cycle are still underexplored. To unveil the possible regulatory effect of this amino acid on gene expression, an integrated study based on quantitative teverse transcription-PCR (qRT-PCR) and proteomic approaches was performed on the actinomycete model Streptomyces coelicolor. Comparative analyses on the microorganism growth in a minimal medium with or without tryptophan supplementation showed that biosynthetic trp gene expression in S. coelicolor is not subjected to a negative regulation by the presence of the end product. Conversely, tryptophan specifically induces the transcription of trp genes present in the biosynthetic gene cluster of the calcium-dependent antibiotic (CDA), a lipopeptide containing D- and L-tryptophan residues. In addition, tryptophan stimulates the transcription of the CDA gene cluster regulator cdaR and, coherently, CDA production. Surprisingly, tryptophan also promotes the production of actinorhodin, another antibiotic that does not contain this amino acid in its structure. Combined 2D-DIGE and nano liquid chromatography electrospray linear ion trap tandem mass spectrometry (LC-ESI-LIT-MS/MS) analyses revealed that tryptophan exerts a growth-stage-dependent global effect on S. coelicolor proteome, stimulating anabolic pathways and promoting the accumulation of key factors associated with morphological and physiological differentiation at the late growth stages. Phenotypic observations by scanning electron microscopy and spore production assays demonstrated an increased sporulation in the presence of tryptophan. Transcriptional analysis of catabolic genes kynA and kynB suggested that the actinomycete also uses tryptophan as a carbon and nitrogen source. In conclusion, this study originally provides the molecular basis underlying the stimulatory

  12. Rating of Perceived Exertion and Physiological Responses in Water-Based Exercise

    Directory of Open Access Journals (Sweden)

    Santana Pinto Stephanie

    2015-12-01

    Full Text Available The aim of the present study was to relate the overall rating of perceived exertion (RPE-overall with cardiorespiratory and neuromuscular variables during stationary running with the elbow flexion/extension performed with water-floating equipment. The sample consisted of eleven women that performed the water-based exercise at submaximal cadences. The heart rate, oxygen uptake, ventilation, and electromyographic signal (EMG from biceps brachii (%EMG BB, triceps brachii (%EMG TB, biceps femoris (%EMG BF and rectus femoris (%EMG RF muscles were measured during the exercise, and the overall RPE was measured immediately following its completion. The Pearson product-moment linear correlation was used to investigate associations between the variables analyzed in the present study. Significant relationships were observed between the RPE-overall and all the cardiorespiratory variables, with the r values ranging from 0.60 to 0.70 (p<0.05. In addition, the RPE-overall showed a significant (p<0.05 relationship with %EMG BB (r=0.55 and %EMG BF (r=0.50. These results suggest an association between the RPE-overall with all cardiorespiratory and two neuromuscular variables during the execution of a water-based aerobic exercise using water-floating equipment.

  13. Physiological responses to, and athlete and coach perceptions of exertion during small-sided basketball games.

    Science.gov (United States)

    Vaquera, A; Suárez-Iglesias, D; Guiu, X; Barroso, R; Thomas, G; Renfree, A

    2017-07-28

    This study describes heart rate (HR) responses during different small sided games (SSGs) in junior basketball players, and identifies the level of agreement between athlete and coach perceptions of internal training load calculated using the in-task rating of perceived exertion (RPE) method. Over a 6 week period, 12 male junior basketball players who played in the Spanish national under-18 League, played 7 games of one-a-side (1v1), 6 games of two-a-side (2v2), 8 games of five-a-side (5v5), and 5 games of superiority (3v2) situations. During 1v1, 2v2, 5v5, and 3v2 peak heart rates were 90.27 ± 3.37%, 92.68 ± 3.29%, 92.01 ± 3.48%, and 88.74 ± 5.77% of HRmax respectively. These differences were statistically significant between 1v1 and 2v2 (P<0.01), 1v1 and 5v5 (P<0.05), 2v2 and 3v2 (P<0.001), and 5v5 and 3v2 (P<0.001). Mean heart rate was 79.5 ± 4.4%, 83.1 ± 4.2%, 91.2 ± 4.7%, and 78.5 ± 7.5% of HRmax during 1v1, 2v2, 5v5, and 3v2, respectively, and differences were observed between 1v1 and 2v2 (P<0.001), 2v2 and 3v2 (P<0.001), and 5v5 and 3v2 (P<0.05). There were differences in athletes and coaches in-task RPE in all SSGs (all P<0.0001 apart from 5x5 P=0.0019). The 2v2 format elicited a higher mean in-task RPE in comparison to all other SSGs (P<0.001), possibly because 2v2 imposes a greater cognitive load.

  14. Differential antibiosis against Helicoverpa armigera exerted by distinct inhibitory repeat domains of Capsicum annuum proteinase inhibitors.

    Science.gov (United States)

    Joshi, Rakesh S; Gupta, Vidya S; Giri, Ashok P

    2014-05-01

    Plant defensive serine proteinase inhibitors (PIs) are known to have negative impact on digestive physiology of herbivore insects and thus have a crucial role in plant protection. Here, we have assessed the efficacy and specificity of three previously characterized inhibitory repeat domain (IRD) variants from Capsicum annuum PIs viz., IRD-7, -9 and -12 against gut proteinases from Helicoverpa armigera. Comparative study of in silico binding energy revealed that IRD-9 possesses higher affinity towards H. armigera serine proteinases as compared to IRD-7 and -12. H. armigera fed on artificial diet containing 5 TIU/g of recombinant IRD proteins exhibited differential effects on larval growth, survival rate and other nutritional parameters. Major digestive gut trypsin and chymotrypsin genes were down regulated in the IRD fed larvae, while few of them were up-regulated, this indicate alterations in insect digestive physiology. The results corroborated with proteinase activity assays and zymography. These findings suggest that the sequence variations among PIs reflect in their efficacy against proteinases in vitro and in vivo, which also could be used for developing tailor-made multi-domain inhibitor gene(s). Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. The Sensitivity of Differential Ratings of Perceived Exertion as Measures of Internal Load.

    Science.gov (United States)

    McLaren, Shaun J; Graham, Michael; Spears, Iain R; Weston, Matthew

    2016-04-01

    To investigate the sensitivity of differential ratings of perceived exertion (dRPE) as measures of internal load. Twenty-two male university soccer players performed 2 maximal incremental-exercise protocols (cycle, treadmill) on separate days. Maximal oxygen uptake (VO2max), maximal heart rate (HRmax), peak blood lactate concentration (B[La]peak), and the preprotocol-to-postprotocol change in countermovement-jump height (ΔCMJH) were measured for each protocol. Players provided dRPE (CR100) for breathlessness (RPE-B) and leg-muscle exertion (RPE-L) immediately on exercise termination (RPE-B0, RPE-L0) and 30 min postexercise (RPE-B30, RPE-L30). Data were analyzed using magnitude-based inferences. There were clear between-protocols differences for VO2max (cycle 46.5 ± 6.3 vs treadmill 51.0 ± 5.1 mL · kg-1 · min-1, mean difference -9.2%; ±90% confidence limits 3.7%), HRmax (184.7 ± 12.7 vs 196.7 ± 7.8 beats/min, -6.0%; ±1.7%), B[La]peak (9.7 ± 2.1 vs 8.5 ± 2.0 mmol/L, 15%; ± 10%), and ΔCMJH (-7.1 ± 4.2 vs 0.6 ± 3.6 cm, -23.2%; ± 5.4%). Clear between-protocols differences were recorded for RPE-B0 (78.0 ± 11.7 vs 94.7 ± 9.5 AU, -18.1%; ± 4.5%), RPE-L0 (92.6 ± 9.7 vs 81.3 ± 14.1 AU, 15.3%; ± 7.6%), RPE-B30 (70 ± 11 vs 82 ± 13 AU, -13.8%; ± 7.3%), and RPE-L30 (86 ± 12 vs 65 ± 19 AU, 37%; ±17%). A substantial timing effect was observed for dRPE, with moderate to large reductions in all scores 30 min postexercise compared with scores collected on exercise termination. dRPE enhance the precision of internal-load measurement and therefore represent a worthwhile addition to training-load-monitoring procedures.

  16. [Psycho-physiological effects of pop music on cardiovascular parameters at rest and during exertion (author's transl)].

    Science.gov (United States)

    Liptak, V

    1979-05-30

    The effects of pop music on heart rate, systolic and diastolic blood pressure at rest, during exercise on a bicycle ergometer and in the recovery phase were investigated. The psychological effects of the music were analysed by means of a question sheet and correlated with the physiological effects. The psychological effects of the music points to a reduction of monotony and of fatigue. During exercise, especially during low physical strain, there was a good correlation between the psychological and the physiological parameters. The significant decrease of the cardiovascular parameters in the recovery phase demonstrates, that emotional stimuli are influencing the heart rate not only at rest and work, but also in the recovery phase. The results of the psycho-physiological experiments give rise to the conclusion, that individual attitude to music doesn't primarily influence the effects of music on physiological reactions.

  17. The Influence of Playing Position and Contextual Factors on Soccer Players’ Match Differential Ratings of Perceived Exertion: A Preliminary Investigation

    Directory of Open Access Journals (Sweden)

    Steve Barrett

    2018-02-01

    Full Text Available (1 Background: Differential RPE (dRPE separates scores for breathlessness (RPE-B, leg muscle exertion (RPE-L and technical/cognitive exertion (RPE-T. Limited information for dRPE is available in soccer match play, yet these measurements may help inform practitioners training and recovery strategies. This preliminary study investigated the effects of playing position and contextual factors on elite soccer players’ dRPE. (2 Methods: Thirty-two male English Premier League players recorded dRPE scores 15–30 min post-match for RPE-B, RPE-L, and RPE-T. Data were analysed using linear mixed models, with magnitude-based inferences subsequently applied. (3 Results: Overall, the mean ± SD for the dRPE were 63 ± 23 arbitrary units (au (RPE-B, 67 ± 22 au (RPE-L, and 60 ± 24 au (RPE-T. Full Backs reported substantially higher RPE-B, RPE-L and RPE-T when compared to all other positions. Substantially higher RPE-T scores were reported for matches played against Top teams compared to Bottom (10 au; 90% Confidence Interval 5 to 15 au and Middle (10 au; 4 to 15 au ranked teams. The effects of match result and location on dRPE were not substantial. (4 Conclusions: Positional differences were observed following soccer match play for RPE-B, RPE-L and RPE-T. Full backs had substantially higher dRPE then any other position, with all players reporting increased RPE-T when playing teams at the Top of the league. These findings can help practitioners monitor internal load responses and support the prescription of training and recovery sessions.

  18. Exertional thermal strain, protective clothing and auxiliary cooling in dry heat: evidence for physiological but not cognitive impairment.

    Science.gov (United States)

    Caldwell, Joanne N; Patterson, Mark J; Taylor, Nigel A S

    2012-10-01

    Individuals exposed to extreme heat may experience reduced physiological and cognitive performance, even during very light work. This can have disastrous effects on the operational capability of aircrew, but such impairment could be prevented by auxiliary cooling devices. This hypothesis was tested under very hot-dry conditions, in which eight males performed 2 h of low-intensity exercise (~30 W) in three trials, whilst wearing biological and chemical protective clothing: temperate (control: 20°C, 30% relative humidity) and two hot-dry trials (48°C, 20% relative humidity), one without (experimental) and one with liquid cooling (water at 15°C). Physiological strain and six cognitive functions were evaluated (MiniCog Rapid Assessment Battery), and participants drank to sustain hydration state. Maximal core temperatures averaged 37.0°C (±0.1) in the control trial, and were significantly elevated in the experimental trial (38.9°C ± 0.3; P cooling reduced maximal core temperatures (37.3°C ± 0.1; P 0.05). However, despite inducing profound hyperthermia and volitional fatigue, no cognitive degradation was evident in the heat (P > 0.05). Since extensive dehydration was prevented, it appears that thermal strain in the absence of dehydration may have minimal impact upon cognitive function, at least as evaluated within this experiment.

  19. Fucoxanthin exerts differing effects on 3T3-L1 cells according to differentiation stage and inhibits glucose uptake in mature adipocytes

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Seong-Il [Department of Biology, Jeju National University, Jejusi, Jeju 690-756 (Korea, Republic of); Ko, Hee-Chul [Jeju Sasa Industry Development Agency, Jeju National University, Jejusi, Jeju 690-756 (Korea, Republic of); Shin, Hye-Sun; Kim, Hyo-Min; Hong, Youn-Suk [Department of Biology, Jeju National University, Jejusi, Jeju 690-756 (Korea, Republic of); Lee, Nam-Ho [Department of Chemistry, Jeju National University, Jejusi, Jeju 690-756 (Korea, Republic of); Kim, Se-Jae, E-mail: sjkim@jejunu.ac.kr [Department of Biology, Jeju National University, Jejusi, Jeju 690-756 (Korea, Republic of); Jeju Sasa Industry Development Agency, Jeju National University, Jejusi, Jeju 690-756 (Korea, Republic of)

    2011-06-17

    Highlights: {yields} Fucoxanthin enhances 3T3-L1 adipocyte differentiation at an early stage. {yields} Fucoxanthin inhibits 3T3-L1 adipocyte differentiation at intermediate and late stages. {yields} Fucoxanthin attenuates glucose uptake by inhibiting the phosphorylation of IRS in mature 3T3-L1 adipocytes. {yields} Fucoxanthin exerts its anti-obesity effect by inhibiting the differentiation of adipocytes at both intermediate and late stages, as well as glucose uptake in mature adipocytes. -- Abstract: Progression of 3T3-L1 preadipocyte differentiation is divided into early (days 0-2, D0-D2), intermediate (days 2-4, D2-D4), and late stages (day 4 onwards, D4-). In this study, we investigated the effects of fucoxanthin, isolated from the edible brown seaweed Petalonia binghamiae, on adipogenesis during the three differentiation stages of 3T3-L1 preadipocytes. When fucoxanthin was applied during the early stage of differentiation (D0-D2), it promoted 3T3-L1 adipocyte differentiation, as evidenced by increased triglyceride accumulation. At the molecular level, fucoxanthin increased protein expression of peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}), CCAAT/enhancer-binding protein {alpha} (C/EBP{alpha}), sterol regulatory element-binding protein 1c (SREBP1c), and aP2, and adiponectin mRNA expression, in a dose-dependent manner. However, it reduced the expression of PPAR{gamma}, C/EBP{alpha}, and SREBP1c during the intermediate (D2-D4) and late stages (D4-D7) of differentiation. It also inhibited the uptake of glucose in mature 3T3-L1 adipocytes by reducing the phosphorylation of insulin receptor substrate 1 (IRS-1). These results suggest that fucoxanthin exerts differing effects on 3T3-L1 cells of different differentiation stages and inhibits glucose uptake in mature adipocytes.

  20. Dementias show differential physiological responses to salient sounds

    Directory of Open Access Journals (Sweden)

    Phillip David Fletcher

    2015-03-01

    Full Text Available Abnormal responsiveness to salient sensory signals is often a prominent feature of dementia diseases, particularly the frontotemporal lobar degenerations, but has been little studied. Here we assessed processing of one important class of salient signals, looming sounds, in canonical dementia syndromes. We manipulated tones using intensity cues to create percepts of salient approaching (‘looming’ or less salient withdrawing sounds. Pupil dilatation responses and behavioural rating responses to these stimuli were compared in patients fulfilling consensus criteria for dementia syndromes (semantic dementia, n=10; behavioural variant frontotemporal dementia, n=16, progressive non-fluent aphasia, n=12; amnestic Alzheimer’s disease, n=10 and a cohort of 26 healthy age-matched individuals. Approaching sounds were rated as more salient than withdrawing sounds by healthy older individuals but this behavioural response to salience did not differentiate healthy individuals from patients with dementia syndromes. Pupil responses to approaching sounds were greater than responses to withdrawing sounds in healthy older individuals and in patients with semantic dementia: this differential pupil response was reduced in patients with progressive nonfluent aphasia and Alzheimer’s disease relative both to the healthy control and semantic dementia groups, and did not correlate with nonverbal auditory semantic function. Autonomic responses to auditory salience are differentially affected by dementias and may constitute a novel biomarker of these diseases.

  1. EFFECT OF EXERCISE INTENSITY ON DIFFERENTIATED AND UNDIFFERENTIATED RATINGS OF PERCEIVED EXERTION DURING CYCLE AND TREADMILL EXERCISE IN RECREATIONALLY ACTIVE AND TRAINED WOMEN

    OpenAIRE

    Melinda R. Bolgar; Baker, Carol E.; GOSS, FREDRIC L.; Elizabeth Nagle; Robertson, Robert J.

    2010-01-01

    The purpose of the study is to examine the effect of aerobic exercise intensity on components of the differentiated perceived exertion model in young women performing weight bearing and non-weight bearing aerobic exercise. Subjects were 18-25 yr old women who were recreationally active (n = 19; VO2max = 33.40 ml·kg-1·min-1) and trained (N = 22; VO2max = 43.3 ml·kg-1·min-1). Subjects underwent two graded exercise tests (GXT) on a treadmill and bike which were separated by 48 hours. RPE-Overall...

  2. Thrombospondin-1, -2 and -5 have differential effects on vascular smooth muscle cell physiology

    Energy Technology Data Exchange (ETDEWEB)

    Helkin, Alex; Maier, Kristopher G. [SUNY Upstate Medical University, Division of Vascular Surgery and Endovascular Services, Syracuse, NY (United States); Department of Veterans Affairs VA Healthcare Network Upstate New York at Syracuse, Syracuse, NY (United States); Gahtan, Vivian, E-mail: gahtanv@upstate.edu [SUNY Upstate Medical University, Division of Vascular Surgery and Endovascular Services, Syracuse, NY (United States); Department of Veterans Affairs VA Healthcare Network Upstate New York at Syracuse, Syracuse, NY (United States)

    2015-09-04

    Introduction: The thrombospondins (TSPs) are matricellular proteins that exert multifunctional effects by binding cytokines, cell-surface receptors and other proteins. TSPs play important roles in vascular pathobiology and are all expressed in arterial lesions. The differential effects of TSP-1, -2, and -5 represent a gap in knowledge in vascular smooth muscle cell (VSMC) physiology. Our objective is to determine if structural differences of the TSPs imparted different effects on VSMC functions critical to the formation of neointimal hyperplasia. We hypothesize that TSP-1 and -2 induce similar patterns of migration, proliferation and gene expression, while the effects of TSP-5 are different. Methods: Human aortic VSMC chemotaxis was tested for TSP-2 and TSP-5 (1–40 μg/mL), and compared to TSP-1 and serum-free media (SFM) using a modified Boyden chamber. Next, VSMCs were exposed to TSP-1, TSP-2 or TSP-5 (0.2–40 μg/mL). Proliferation was assessed by MTS assay. Finally, VSMCs were exposed to TSP-1, TSP-2, TSP-5 or SFM for 3, 6 or 24 h. Quantitative real-time PCR was performed on 96 genes using a microfluidic card. Statistical analysis was performed by ANOVA or t-test, with p < 0.05 being significant. Results: TSP-1, TSP-2 and TSP-5 at 20 μg/mL all induce chemotaxis 3.1 fold compared to serum-free media. TSP-1 and TSP-2 induced proliferation 53% and 54% respectively, whereas TSP-5 did not. In the gene analysis, overall, cardiovascular system development and function is the canonical pathway most influenced by TSP treatment, and includes multiple growth factors, cytokines and proteases implicated in cellular migration, proliferation, vasculogenesis, apoptosis and inflammation pathways. Conclusions and relevance: The results of this study indicate TSP-1, -2, and -5 play active roles in VSMC physiology and gene expression. Similarly to TSP-1, VSMC chemotaxis to TSP-2 and -5 is dose-dependent. TSP-1 and -2 induces VSMC proliferation, but TSP-5 does not, likely

  3. Typhoons exert significant but differential impacts on net ecosystem carbon exchange of subtropical mangrove forests in China

    Science.gov (United States)

    Chen, H.; Lu, W.; Yan, G.; Yang, S.; Lin, G.

    2014-10-01

    Typhoons are very unpredictable natural disturbances to subtropical mangrove forests in Asian countries, but little information is available on how these disturbances affect ecosystem level carbon dioxide (CO2) exchange of mangrove wetlands. In this study, we examined short-term effect of frequent strong typhoons on defoliation and net ecosystem CO2 exchange (NEE) of subtropical mangroves, and also synthesized 19 typhoons during a 4-year period between 2009 and 2012 to further investigate the regulation mechanisms of typhoons on ecosystem carbon and water fluxes following typhoon disturbances. Strong wind and intensive rainfall caused defoliation and local cooling effect during the typhoon season. Daily total NEE values decreased by 26-50% following some typhoons (e.g., W28-Nockten, W35-Molave and W35-Lio-Fan), but significantly increased (43-131%) following typhoon W23-Babj and W38-Megi. The magnitudes and trends of daily NEE responses were highly variable following different typhoons, which were determined by the balance between the variances of gross ecosystem production (GEP) and ecosystem respiration (RE). Furthermore, results from our synthesis indicated that the landfall time of typhoon, wind speed and rainfall were the most important factors controlling the CO2 fluxes following typhoon events. These findings indicate that different types of typhoon disturbances can exert very different effects on CO2 fluxes of mangrove ecosystems and that typhoon will likely have larger impacts on carbon cycle processes in subtropical mangrove ecosystems as the intensity and frequency of typhoons are predicted to increase under future global climate change scenarios.

  4. Arctigenin exerts anti-colitis efficacy through inhibiting the differentiation of Th1 and Th17 cells via an mTORC1-dependent pathway.

    Science.gov (United States)

    Wu, Xin; Dou, Yannong; Yang, Yan; Bian, Difei; Luo, Jinque; Tong, Bei; Xia, Yufeng; Dai, Yue

    2015-08-15

    Arctigenin, the main effective constituent of Arctium lappa L. fruit, has previously been proven to dramatically attenuate dextran sulfate sodium (DSS)-induced colitis in mice, a frequently used animal model of inflammatory bowel disease (IBD). As Th1 and Th17 cells play a crucial role in the pathogenesis of IBD, the present study addressed whether and how arctigenin exerted anti-colitis efficacy by interfering with the differentiation and activation of Th1/Th17 cells. In vitro, arctigenin was shown to markedly inhibit the differentiation of Th17 cells from naïve T cells, and moderately inhibit the differentiation of Th1 cells, which was accompanied by lowered phosphorylation of STAT3 and STAT4, respectively. In contrast, arctigenin was lack of marked effect on the differentiation of either Th2 or regulatory T cells. Furthermore, arctigenin was shown to suppress the mammalian target of rapamycin complex 1 (mTORC1) pathway in T cells as demonstrated by down-regulated phosphorylation of the downstream target genes p70S6K and RPS6, and it functioned independent of two well-known upstream kinases PI3K/AKT and ERK. Arctigenin was also able to inhibit the activity of mTORC1 by dissociating raptor from mTOR. Interestingly, the inhibitory effect of arctigenin on T cell differentiation disappeared under a status of mTORC1 overactivation via knockdown of tuberous sclerosis complex 2 (TSC2, a negative regulator of mTORC1) or pretreatment of leucine (an agonist of mTOR). In DSS-induced mice, the inhibition of Th1/Th17 responses and anti-colitis effect of arctigenin were abrogated by leucine treatment. In conclusion, arctigenin ameliorates colitis through down-regulating the differentiation of Th1 and Th17 cells via mTORC1 pathway. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Differential cytotoxicity of MEX: a component of Neem oil whose action is exerted at the cell membrane level.

    Science.gov (United States)

    Ricci, Francesca; Berardi, Valerio; Risuleo, Gianfranco

    2008-12-31

    Neem oil is obtained from the seeds of the tree Azadirachta indica. Its chemical composition is very complex, being rich in terpenoids and limonoids, as well as volatile sulphur modified compounds. This work focused on the evaluation of a component of the whole Neem oil obtained by methanolic extraction and defined as MEX. Cytotoxicity was assessed on two different cell populations: a stabilized murine fibroblast line (3T6) and a tumor cell line (HeLa). The data presented here suggest a differential sensitivity of these two populations, the tumor line exhibiting a significantly higher sensitivity to MEX. The data strongly suggest that its toxic target is the cell membrane. In addition the results presented here imply that MEX may contain one or more agents that could find a potential use in anti-proliferative therapy.

  6. Differential Cytotoxicity of MEX: a Component of Neem Oil Whose Action Is Exerted at the Cell Membrane Level

    Directory of Open Access Journals (Sweden)

    Francesca Ricci

    2008-12-01

    Full Text Available Neem oil is obtained from the seeds of the tree Azadirachta indica. Its chemical composition is very complex, being rich in terpenoids and limonoids, as well as volatile sulphur modified compounds. This work focused on the evaluation of a component of the whole Neem oil obtained by methanolic extraction and defined as MEX. Cytotoxicity was assessed on two different cell populations: a stabilized murine fibroblast line (3T6 and a tumor cell line (HeLa. The data presented here suggest a differential sensitivity of these two populations, the tumor line exhibiting a significantly higher sensitivity to MEX. The data strongly suggest that its toxic target is the cell membrane. In addition the results presented here imply that MEX may contain one or more agents that could find a potential use in anti-proliferative therapy.

  7. Physiology

    Science.gov (United States)

    Kay, Ian

    2008-01-01

    Underlying recent developments in health care and new treatments for disease are advances in basic medical sciences. This edition of "Webwatch" focuses on sites dealing with basic medical sciences, with particular attention given to physiology. There is a vast amount of information on the web related to physiology. The sites that are included here…

  8. Differentiating tumefactive demyelinating lesion from neoplasm - Does physiologic MR imaging help?

    Energy Technology Data Exchange (ETDEWEB)

    Low, Choon Kuang, E-mail: choonkuang@gmail.co [Singapore General Hospital, Department of Diagnostic Radiology, Outram Road, Singapore 169608 (Singapore); Lim, Winston E.H.; Rumpel, Helmut [Singapore General Hospital, Department of Diagnostic Radiology, Outram Road, Singapore 169608 (Singapore)

    2011-02-15

    Background: A tumefactive demyelinating lesion (TDL) often masquerades as a brain tumour and poses a diagnostic dilemma which may result in unnecessary surgery in some rare cases. This case emphasizes the need for caution when confronted with a patient whose differential diagnosis is between TDL and neoplasm. Summary of report: A 31-year-old woman was diagnosed as having a brain neoplasm. She was referred to our institution for further diagnostic imaging and treatment. Structural and physiologic scan were performed and these findings suggested a TDL rather than a neoplasm. Stereotactic biopsy of the lesion showed findings in keeping with demyelinating disease. The patient received steroid treatment, and showed improvement. Conclusion: The utility of the physiologic technique with structural scan may lead to an increased accuracy in differentiating TDL from neoplasm.

  9. Low physiologic oxygen tensions reduce proliferation and differentiation of human multipotent mesenchymal stromal cells

    Directory of Open Access Journals (Sweden)

    Handgretinger Rupert

    2010-01-01

    Full Text Available Abstract Background Human multipotent mesenchymal stromal cells (MSC can be isolated from various tissues including bone marrow. Here, MSC participate as bone lining cells in the formation of the hematopoietic stem cell niche. In this compartment, the oxygen tension is low and oxygen partial pressure is estimated to range from 1% to 7%. We analyzed the effect of low oxygen tensions on human MSC cultured with platelet-lysate supplemented media and assessed proliferation, morphology, chromosomal stability, immunophenotype and plasticity. Results After transferring MSC from atmospheric oxygen levels of 21% to 1%, HIF-1α expression was induced, indicating efficient oxygen reduction. Simultaneously, MSC exhibited a significantly different morphology with shorter extensions and broader cell bodies. MSC did not proliferate as rapidly as under 21% oxygen and accumulated in G1 phase. The immunophenotype, however, was unaffected. Hypoxic stress as well as free oxygen radicals may affect chromosomal stability. However, no chromosomal abnormalities in human MSC under either culture condition were detected using high-resolution matrix-based comparative genomic hybridization. Reduced oxygen tension severely impaired adipogenic and osteogenic differentiation of human MSC. Elevation of oxygen from 1% to 3% restored osteogenic differentiation. Conclusion Physiologic oxygen tension during in vitro culture of human MSC slows down cell cycle progression and differentiation. Under physiological conditions this may keep a proportion of MSC in a resting state. Further studies are needed to analyze these aspects of MSC in tissue regeneration.

  10. The Caenorhabditis elegans epidermis as a model skin. II: differentiation and physiological roles.

    Science.gov (United States)

    Chisholm, Andrew D; Xu, Suhong

    2012-01-01

    The Caenorhabditis elegans epidermis forms one of the principal barrier epithelia of the animal. Differentiation of the epidermis begins in mid embryogenesis and involves apical-basal polarization of the cytoskeletal and secretory systems as well as cellular junction formation. Secretion of the external cuticle layers is one of the major developmental and physiological specializations of the epidermal epithelium. The four post-embryonic larval stages are separated by periodic moults, in which the epidermis generates a new cuticle with stage-specific characteristics. The differentiated epidermis also plays key roles in endocrine signaling, fat storage, and ionic homeostasis. The epidermis is intimately associated with the development and function of the nervous system, and may have glial-like roles in modulating neuronal function. The epidermis provides passive and active defenses against skin-penetrating pathogens and can repair small wounds. Finally, age-dependent deterioration of the epidermis is a prominent feature of aging and may affect organismal aging and lifespan.

  11. Face and voice as social stimuli enhance differential physiological responding in a Concealed Information Test

    Directory of Open Access Journals (Sweden)

    Wolfgang eAmbach

    2012-11-01

    Full Text Available Attentional, intentional, and motivational factors are known to influence the physiological responses in a Concealed Information Test (CIT. Although concealing information is essentially a social action closely related to motivation, CIT studies typically rely on testing participants in an environment lacking of social stimuli: Subjects interact with a computer while sitting alone in an experimental room. To address this gap, we examined the influence of social stimuli on the physiological responses in a CIT.Seventy-one participants underwent a mock-crime experiment with a modified CIT. In a between-subjects design, subjects were either questioned acoustically by a pre-recorded male voice presented together with a virtual male experimenter’s uniform face or by a text field on the screen, which displayed the question devoid of face and voice. Electrodermal activity (EDA, respiration line length (RLL, phasic heart rate (pHR, and finger pulse waveform length (FPWL were registered. The Psychopathic Personality Inventory - Revised (PPI-R was administered in addition. The differential responses of RLL, pHR, and FPWL to probe vs. irrelevant items were greater in the condition with social stimuli than in the text condition; interestingly, the differential responses of EDA did not differ between conditions. No modulatory influence of the PPI-R sum or subscale scores was found.The results emphasize the relevance of social aspects in the process of concealing information and in its detection. Attentional demands as well as the participants’ motivation to avoid detection might be the important links between social stimuli and physiological responses in the CIT.

  12. EFFECT OF EXERCISE INTENSITY ON DIFFERENTIATED AND UNDIFFERENTIATED RATINGS OF PERCEIVED EXERTION DURING CYCLE AND TREADMILL EXERCISE IN RECREATIONALLY ACTIVE AND TRAINED WOMEN

    Directory of Open Access Journals (Sweden)

    Melinda R. Bolgar

    2010-12-01

    Full Text Available The purpose of the study is to examine the effect of aerobic exercise intensity on components of the differentiated perceived exertion model in young women performing weight bearing and non-weight bearing aerobic exercise. Subjects were 18-25 yr old women who were recreationally active (n = 19; VO2max = 33.40 ml·kg-1·min-1 and trained (N = 22; VO2max = 43.3 ml·kg-1·min-1. Subjects underwent two graded exercise tests (GXT on a treadmill and bike which were separated by 48 hours. RPE-Overall, -Legs, and -Chest, as well as oxygen uptake (VO2 and heart rate were recorded each minute. Individual regression analyses were used to identify RPE-Overall,-Legs, and -Chest at 40, 60, 80% VO2max/peak. Separate two factor (site (3 x intensity (3 ANOVAs with repeated measures on site and intensity were computed for each training status. Furthermore, RPE responses were also examined with a one factor (site (3 within subject ANOVA with repeated measure on site at the ventilatory breakpoint. For both the recreationally active and trained groups no significant differences were observed for RPE-Overall, -Legs, and -Chest during treadmill exercise. However, for cycling exercise results indicated that RPE-Legs was significantly greater at all exercise intensities than RPE-Overall and RPE-Chest for trained subjects while for recreationally active subjects RPE-Legs was only significantly higher at the highest exercise intensity. Responses at the ventilatory breakpoint during cycle exercise indicated that RPE-Legs was significantly greater than RPE-Chest and RPE-Overall for trained subjects but not for recreationally active subjects. Signal dominance was not observed at an intensity equivalent to the ventilatory breakpoint during treadmill exercise in either of the groups. In recreationally active and trained females signal dominance was demonstrated only during cycling exercise, but not during treadmill exercise. Signal integration could not be demonstrated during

  13. Chronic Exertional Compartment Syndrome.

    Science.gov (United States)

    Braver, Richard T

    2016-04-01

    Increased tissue pressure within a fascial compartment may be the result from any increase in volume within its contents, or any decrease in size of the fascial covering or its distensibility. This may lead to symptoms of leg tightness, pain or numbness brought about by exercise. There are multiple differential diagnoses of exercise induced leg pain and the proper diagnoses of chronic exertional compartment syndrome (CECS) is made by a careful history and by exclusion of other maladies and confirmed by compartment syndrome testing as detailed in this text. Surgical fasciotomies for the anterior, lateral, superficial and deep posterior compartments are described in detail along with ancillary procedures for chronic shin splints that should allow the athlete to return to competitive activity. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Methodological Choices in Muscle Synergy Analysis Impact Differentiation of Physiological Characteristics Following Stroke

    Directory of Open Access Journals (Sweden)

    Caitlin L. Banks

    2017-08-01

    Full Text Available Muscle synergy analysis (MSA is a mathematical technique that reduces the dimensionality of electromyographic (EMG data. Used increasingly in biomechanics research, MSA requires methodological choices at each stage of the analysis. Differences in methodological steps affect the overall outcome, making it difficult to compare results across studies. We applied MSA to EMG data collected from individuals post-stroke identified as either responders (RES or non-responders (nRES on the basis of a critical post-treatment increase in walking speed. Importantly, no clinical or functional indicators identified differences between the cohort of RES and nRES at baseline. For this exploratory study, we selected the five highest RES and five lowest nRES available from a larger sample. Our goal was to assess how the methodological choices made before, during, and after MSA affect the ability to differentiate two groups with intrinsic physiologic differences based on MSA results. We investigated 30 variations in MSA methodology to determine which choices allowed differentiation of RES from nRES at baseline. Trial-to-trial variability in time-independent synergy vectors (SVs and time-varying neural commands (NCs were measured as a function of: (1 number of synergies computed; (2 EMG normalization method before MSA; (3 whether SVs were held constant across trials or allowed to vary during MSA; and (4 synergy analysis output normalization method after MSA. MSA methodology had a strong effect on our ability to differentiate RES from nRES at baseline. Across all 10 individuals and MSA variations, two synergies were needed to reach an average of 90% variance accounted for (VAF. Based on effect sizes, differences in SV and NC variability between groups were greatest using two synergies with SVs that varied from trial-to-trial. Differences in SV variability were clearest using unit magnitude per trial EMG normalization, while NC variability was less sensitive to EMG

  15. Contractility of single cardiomyocytes differentiated from pluripotent stem cells depends on physiological shape and substrate stiffness.

    Science.gov (United States)

    Ribeiro, Alexandre J S; Ang, Yen-Sin; Fu, Ji-Dong; Rivas, Renee N; Mohamed, Tamer M A; Higgs, Gadryn C; Srivastava, Deepak; Pruitt, Beth L

    2015-10-13

    Single cardiomyocytes contain myofibrils that harbor the sarcomere-based contractile machinery of the myocardium. Cardiomyocytes differentiated from human pluripotent stem cells (hPSC-CMs) have potential as an in vitro model of heart activity. However, their fetal-like misalignment of myofibrils limits their usefulness for modeling contractile activity. We analyzed the effects of cell shape and substrate stiffness on the shortening and movement of labeled sarcomeres and the translation of sarcomere activity to mechanical output (contractility) in live engineered hPSC-CMs. Single hPSC-CMs were cultured on polyacrylamide substrates of physiological stiffness (10 kPa), and Matrigel micropatterns were used to generate physiological shapes (2,000-µm(2) rectangles with length:width aspect ratios of 5:1-7:1) and a mature alignment of myofibrils. Translation of sarcomere shortening to mechanical output was highest in 7:1 hPSC-CMs. Increased substrate stiffness and applied overstretch induced myofibril defects in 7:1 hPSC-CMs and decreased mechanical output. Inhibitors of nonmuscle myosin activity repressed the assembly of myofibrils, showing that subcellular tension drives the improved contractile activity in these engineered hPSC-CMs. Other factors associated with improved contractility were axially directed calcium flow, systematic mitochondrial distribution, more mature electrophysiology, and evidence of transverse-tubule formation. These findings support the potential of these engineered hPSC-CMs as powerful models for studying myocardial contractility at the cellular level.

  16. The C. elegans epidermis as a model skin. II: differentiation and physiological roles

    Science.gov (United States)

    Xu, Suhong

    2012-01-01

    The C. elegans epidermis forms one of the principal barrier epithelia of the animal. Differentiation of the epidermis begins in mid embryogenesis and involves apical-basal polarization of the cytoskeletal and secretory systems as well as cellular junction formation. Secretion of the external cuticle layers is one of the major developmental and physiological specializations of the epidermal epithelium. The four post-embryonic larval stages are separated by periodic moults, in which the epidermis generates a new cuticle with stage-specific characteristics. The differentiated epidermis also plays key roles in endocrine signaling, fat storage, and ionic homeostasis. The epidermis is intimately associated with the development and function of the nervous system, and may have glial-like roles in modulating neuronal function. The epidermis provides passive and active defenses against skin-penetrating pathogens and can repair small wounds. Finally, age-dependent deterioration of the epidermis is a prominent feature of aging and may affect organismal aging and lifespan. PMID:23539358

  17. Truncation of PITX2 differentially affects its activity on physiological targets.

    Science.gov (United States)

    Quentien, Marie-Hélène; Vieira, Véronique; Menasche, Maurice; Dufier, Jean-Louis; Herman, Jean-Paul; Enjalbert, Alain; Abitbol, Marc; Brue, Thierry

    2011-02-01

    The bicoid-like transcription factor PITX2 has been previously described to interact with the pituitary-specific POU homeodomain factor POU1F1 (human ortholog of PIT-1) to achieve cell-specific expression of prolactin (PRL) and GH in pituitary somatolactotroph cells. In this work, we have investigated the functional properties of three PITX2 mutants reported in Axenfeld-Rieger syndrome patients relative to the regulation of these genes, using reporter genes under the control of human PRL (hPRL), hGH, or POU1F1 promoters transfected in nonpituitary and pituitary cell lines. Among the three mutations studied, Y167X and E101X introduce a premature stop codon, and F104L leads to an amino acid substitution. While PITX2(E101X) is not expressed in the cells following transfection, and PITX2(F104L) is functionally inactive, the PITX2(Y167X) mutant keeps its DNA-binding capacity and displays a markedly enhanced activation of the hPRL and POU1F1 promoters, but not of the hGH promoter. Y167X is the first mutation of PITX2 described to result in a differential effect on the activation of its different physiological targets, hPRL and POU1F1 on one hand and hGH on the other hand. The differential effect of the Y167X mutation might be linked to an interaction of PITX2 with different transcription factors or cofactors when bound to the hPRL and POU1F1 or the hGH promoters. These results might form the basis for the identification of the PITX2 protein complex necessary for the differential GH or PRL expression.

  18. Differential physiological and biochemical responses of two Vigna species under enhanced UV-B radiation

    Directory of Open Access Journals (Sweden)

    Rajiv Dwivedi

    2015-04-01

    Full Text Available Differential physiological and biochemical responses of two Vigna spp. i.e. Vigna mungo (L. and Vigna acontifolia (Jacq. seedlings exposed to enhanced ultraviolet-B (ambient+supplemental, 280–320 nm radiation were studied. UV-B radiation accelerated the generation of ROS i.e. superoxide radical (O2·−–, hydrogen peroxide (H2O2 and hydroxyl radical (·−OH in leaves, and concomitantly damaging effects on lipid peroxidation, electrolyte leakage and growth in both Vigna spp. were noticed in dose dependent manner, but V. mungo exhibited greater UV-B damaging effects. UV-B stress induced positive response on antioxidants: superoxide dismutase (SOD and guaiacol peroxidase (GPX activity, and contents of proline, ascorbic acid, total phenolic contents (TPCs and total flavonoid contents (TFCs in leaves of both spp., however, catalase (CAT exhibited varied activity. The study concludes that substantially higher contents of TPCs and TFCs in epidermal layer, proline and ascorbic acid, and higher CAT activity before and after enhanced UV-B exposure probably attributed greater tolerance to V. acontifolia species, thus exhibited lesser UV-B induced damaging effects on cellular components and growth than that of V. mungo. This study also suggests that V. acontifolia is comparatively resistant to UV-B and thus may be useful for practical cultivation.

  19. Non-CpG Oligonucleotides Exert Adjuvant Effects by Enhancing Cognate B Cell-T Cell Interactions, Leading to B Cell Activation, Differentiation, and Isotype Switching

    Directory of Open Access Journals (Sweden)

    Melinda Herbáth

    2015-01-01

    Full Text Available Natural and synthetic nucleic acids are known to exert immunomodulatory properties. Notably, nucleic acids are known to modulate immune function via several different pathways and various cell types, necessitating a complex interpretation of their effects. In this study we set out to compare the effects of a CpG motif containing oligodeoxynucleotide (ODN with those of a control and an inhibitory non-CpG ODN during cognate B cell-T cell interactions. We employed an antigen presentation system using splenocytes from TCR transgenic DO11.10 mice and the ovalbumin peptide recognized by the TCR as model antigen. We followed early activation events by measuring CD69 expression, late activation by MHC class II expression, cell division and antibody production of switched, and nonswitched isotypes. We found that both of the tested non-CpG ODN exerted significant immunomodulatory effects on early T cell and on late B cell activation events. Importantly, a synergism between non-CpG effects and T cell help acting on B cells was observed, resulting in enhanced IgG production following cognate T cell-B cell interactions. We propose that non-CpG ODN may perform as better adjuvants when a strong antigen-independent immune activation, elicited by CpG ODNs, is undesirable.

  20. Non-CpG Oligonucleotides Exert Adjuvant Effects by Enhancing Cognate B Cell-T Cell Interactions, Leading to B Cell Activation, Differentiation, and Isotype Switching

    Science.gov (United States)

    Herbáth, Melinda; Papp, Krisztián; Erdei, Anna; Prechl, József

    2015-01-01

    Natural and synthetic nucleic acids are known to exert immunomodulatory properties. Notably, nucleic acids are known to modulate immune function via several different pathways and various cell types, necessitating a complex interpretation of their effects. In this study we set out to compare the effects of a CpG motif containing oligodeoxynucleotide (ODN) with those of a control and an inhibitory non-CpG ODN during cognate B cell-T cell interactions. We employed an antigen presentation system using splenocytes from TCR transgenic DO11.10 mice and the ovalbumin peptide recognized by the TCR as model antigen. We followed early activation events by measuring CD69 expression, late activation by MHC class II expression, cell division and antibody production of switched, and nonswitched isotypes. We found that both of the tested non-CpG ODN exerted significant immunomodulatory effects on early T cell and on late B cell activation events. Importantly, a synergism between non-CpG effects and T cell help acting on B cells was observed, resulting in enhanced IgG production following cognate T cell-B cell interactions. We propose that non-CpG ODN may perform as better adjuvants when a strong antigen-independent immune activation, elicited by CpG ODNs, is undesirable. PMID:26380319

  1. Differential Roles of Environmental Enrichment in Alzheimer’s Type of Neurodegeneration and Physiological Aging

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    Vladimir V. Salmin

    2017-07-01

    Full Text Available Impairment of hippocampal adult neurogenesis in aging or degenerating brain is a well-known phenomenon caused by the shortage of brain stem cell pool, alterations in the local microenvironment within the neurogenic niches, or deregulation of stem cell development. Environmental enrichment (EE has been proposed as a potent tool to restore brain functions, to prevent aging-associated neurodegeneration, and to cure neuronal deficits seen in neurodevelopmental and neurodegenerative disorders. Here, we report our data on the effects of environmental enrichment on hippocampal neurogenesis in vivo and neurosphere-forming capacity of hippocampal stem/progenitor cells in vitro. Two models – Alzheimer’s type of neurodegeneration and physiological brain aging – were chosen for the comparative analysis of EE effects. We found that environmental enrichment greatly affects the expression of markers specific for stem cells, progenitor cells and differentiated neurons (Pax6, Ngn2, NeuroD1, NeuN in the hippocampus of young adult rats or rats with Alzheimer’s disease (AD model but less efficiently in aged animals. Application of time-lag mathematical model for the analysis of impedance traces obtained in real-time monitoring of cell proliferation in vitro revealed that EE could restore neurosphere-forming capacity of hippocampal stem/progenitor cells more efficiently in young adult animals (fourfold greater in the control group comparing to the AD model group but not in the aged rats (no positive effect of environmental enrichment at all. In accordance with the results obtained in vivo, EE was almost ineffective in the recovery of hippocampal neurogenic reserve in vitro in aged, but not in amyloid-treated or young adult, rats. Therefore, EE-based neuroprotective strategies effective in Aβ-affected brain could not be directly extrapolated to aged brain.

  2. Repeated treatment with haloperidol and clozapine exerts differential effects on dye coupling between neurons in subregions of striatum and nucleus accumbens.

    Science.gov (United States)

    Onn, S P; Grace, A A

    1995-11-01

    The delayed onset of action of antipsychotic drugs (APDs) during the treatment of schizophrenia has been hypothesized to temporally correlate with the induction of depolarization block in rat mesencephalic dopamine (DA) cell groups. Nevertheless, it is unknown whether these drugs also exert a delayed action on the dopaminoceptive postsynaptic target cells in the striatal complex. Using in vivo intracellular recording and dye labeling techniques, the effects of APDs on dye coupling were examined in subregions of the striatal complex defined by double staining for calbindin immunoreactivity. Rats treated repeatedly with APDs were found to exhibit a 66-71% higher incidence of coupling that occurred in a drug- and a region-specific manner, that is, both drug treatments increased dye coupling in the limbic-associated accumbens shell region whereas only haloperidol increased dye coupling in the motor-related striatal matrix and accumbens core regions. In addition, cells located in regions in which dye coupling was altered also showed significantly higher input resistance. These changes were not observed in response to DA receptor blockade by acute drug administration or when haloperidol was administered for a period sufficient to induce DA receptor supersensitivity but not DA cell depolarization block (i.e., 2 weeks). Therefore, alteration in dye coupling appears to be correlated temporally with the induction of DA cell depolarization block. The finding that both APDs exert a common action on neurons in the accumbens shell region is consistent with its identification as the site of therapeutic drug actions, whereas the capacity of haloperidol to also affect cells in the motor-related matrix and core regions correlates with its high propensity to induce extrapyramidal side effects.

  3. Differential and Conditional Activation of PKC-Isoforms Dictates Cardiac Adaptation during Physiological to Pathological Hypertrophy

    Science.gov (United States)

    Naskar, Shaon; Datta, Kaberi; Mitra, Arkadeep; Pathak, Kanchan; Datta, Ritwik; Bansal, Trisha; Sarkar, Sagartirtha

    2014-01-01

    A cardiac hypertrophy is defined as an increase in heart mass which may either be beneficial (physiological hypertrophy) or detrimental (pathological hypertrophy). This study was undertaken to establish the role of different protein kinase-C (PKC) isoforms in the regulation of cardiac adaptation during two types of cardiac hypertrophy. Phosphorylation of specific PKC-isoforms and expression of their downstream proteins were studied during physiological and pathological hypertrophy in 24 week male Balb/c mice (Mus musculus) models, by reverse transcriptase-PCR, western blot analysis and M-mode echocardiography for cardiac function analysis. PKC-δ was significantly induced during pathological hypertrophy while PKC-α was exclusively activated during physiological hypertrophy in our study. PKC-δ activation during pathological hypertrophy resulted in cardiomyocyte apoptosis leading to compromised cardiac function and on the other hand, activation of PKC-α during physiological hypertrophy promoted cardiomyocyte growth but down regulated cellular apoptotic load resulting in improved cardiac function. Reversal in PKC-isoform with induced activation of PKC-δ and simultaneous inhibition of phospho-PKC-α resulted in an efficient myocardium to deteriorate considerably resulting in compromised cardiac function during physiological hypertrophy via augmentation of apoptotic and fibrotic load. This is the first report where PKC-α and -δ have been shown to play crucial role in cardiac adaptation during physiological and pathological hypertrophy respectively thereby rendering compromised cardiac function to an otherwise efficient heart by conditional reversal of their activation. PMID:25116170

  4. Differential and conditional activation of PKC-isoforms dictates cardiac adaptation during physiological to pathological hypertrophy.

    Science.gov (United States)

    Naskar, Shaon; Datta, Kaberi; Mitra, Arkadeep; Pathak, Kanchan; Datta, Ritwik; Bansal, Trisha; Sarkar, Sagartirtha

    2014-01-01

    A cardiac hypertrophy is defined as an increase in heart mass which may either be beneficial (physiological hypertrophy) or detrimental (pathological hypertrophy). This study was undertaken to establish the role of different protein kinase-C (PKC) isoforms in the regulation of cardiac adaptation during two types of cardiac hypertrophy. Phosphorylation of specific PKC-isoforms and expression of their downstream proteins were studied during physiological and pathological hypertrophy in 24 week male Balb/c mice (Mus musculus) models, by reverse transcriptase-PCR, western blot analysis and M-mode echocardiography for cardiac function analysis. PKC-δ was significantly induced during pathological hypertrophy while PKC-α was exclusively activated during physiological hypertrophy in our study. PKC-δ activation during pathological hypertrophy resulted in cardiomyocyte apoptosis leading to compromised cardiac function and on the other hand, activation of PKC-α during physiological hypertrophy promoted cardiomyocyte growth but down regulated cellular apoptotic load resulting in improved cardiac function. Reversal in PKC-isoform with induced activation of PKC-δ and simultaneous inhibition of phospho-PKC-α resulted in an efficient myocardium to deteriorate considerably resulting in compromised cardiac function during physiological hypertrophy via augmentation of apoptotic and fibrotic load. This is the first report where PKC-α and -δ have been shown to play crucial role in cardiac adaptation during physiological and pathological hypertrophy respectively thereby rendering compromised cardiac function to an otherwise efficient heart by conditional reversal of their activation.

  5. Season exerts differential effects of ocean acidification and warming on growth and carbon metabolism of the seaweed Fucus vesiculosus in the western Baltic Sea

    Directory of Open Access Journals (Sweden)

    Angelika eGraiff

    2015-12-01

    Full Text Available Warming and acidification of the oceans as a consequence of increasing CO2-concentrations occur at large scales. Numerous studies have shown the impact of single stressors on individual species. However, studies on the combined effect of multiple stressors on a multi-species assemblage, which is ecologically much more realistic and relevant, are still scarce. Therefore, we orthogonally crossed the two factors warming and acidification in mesocosm experiments and studied their single and combined impact on the brown alga Fucus vesiculosus associated with its natural community (epiphytes and mesograzers in the Baltic Sea in all seasons (from April 2013 to April 2014. We superimposed our treatment factors onto the natural fluctuations of all environmental variables present in the Benthocosms in so-called delta-treatments. Thereby we compared the physiological responses of F. vesiculosus (growth and metabolites to the single and combined effects of natural Kiel Fjord temperatures and pCO2 conditions with a 5 °C temperature increase and/or pCO2 increase treatment (1100 ppm in the headspace above the mesocosms. Responses were also related to the factor photoperiod which changes over the course of the year. Our results demonstrate complex seasonal pattern. Elevated pCO2 positively affected growth of F. vesiculosus alone and/or interactively with warming. The response direction (additive, synergistic or antagonistic, however, depended on season and daylength. The effects were most obvious when plants were actively growing during spring and early summer. Our study revealed for the first time that it is crucial to always consider the impact of variable environmental conditions throughout all seasons. In summary, our study indicates that in future F. vesiculosus will be more affected by detrimental summer heat-waves than by ocean acidification although the latter consequently enhances growth throughout the year. The mainly negative influence of rising

  6. Induction of temporally dissociated morphological and physiological differentiation of N1E-115 cells.

    Science.gov (United States)

    Cosgrove, C; Cobbett, P

    1991-07-01

    Clonal cells derived from neural tumors have been widely used to study the processes of neuronal differentiation in vitro. The murine neuroblastoma clone N1E-115 has recently been shown to differentiate morphologically in response to removal of serum from the culture medium. In the present study, the nature and time course of electrophysiological differentiation of N1E-115 cells maintained in serum-free medium was examined. Differentiated cells had a higher resting potential and lower input conductance than nondifferentiated cells. Differentiated but not nondifferentiated cells generated current evoked action potentials, and differentiated cells fired spontaneous, repetitive action potentials after 13 days in serum-free medium. The rate of potential change during the depolarizing and repolarizing phases of the action potential became faster as the duration of maintenance of cells in serum-free medium increased. Remarkably, morphological differentiation appeared to be complete after exposure to serum-free medium for 5 days but electrophysiological differentiation was not complete until 13 days in this medium.

  7. Monoterpene α-thujone exerts a differential inhibitory action on GABA(A) receptors implicated in phasic and tonic GABAergic inhibition.

    Science.gov (United States)

    Czyzewska, Marta M; Mozrzymas, Jerzy W

    2013-02-28

    A monoterpene ketone, α-thujone originally attracted attention as a major natural ingredient of absinthe and was suspected to cause adverse effects such as hallucinations and seizures in persons excessively consuming this beverage. Although subsequent studies ruled out any major role of α-thujone in the "absynthism", it was found that at high doses it may induce epileptic activity pointing to an interaction with GABAergic inhibition. Indeed, subsequent studies, including those from this laboratory, showed that α-thujone inhibits GABAergic currents. However, GABAA receptors are extremely heterogeneous and in the present study we have investigated the effect of α-thujone on different recombinant GABAA receptors (α1β2γ2L, α1β2, α1β2δ and α4β2δ) relevant to phasic or tonic forms of inhibition. We report that α-thujone inhibits all considered receptor types by a qualitatively similar mechanism but the strongest effect is observed for α1β2δ receptors, suggesting that tonic currents might be more sensitive to α-thujone than the phasic ones. Moreover, we demonstrate that tonic currents, mimicked by response to a submicromollar GABA concentration (0.3 μM) in cultured neurons, showed a substantially larger sensitivity to α-thujone than responses elicited by higher [GABA] (more similar to phasic currents) or Inhibitory Postsynaptic Currents in the same preparation. Importantly, the extent of tonic current inhibition by α-thujone was as strong as in the case of currents mediated by α1β2δ receptors. Altogether, these data provide evidence that different GABAA receptor subtypes show distinct sensitivities to α-thujone and suggest that this compound may differentially affect tonic and phasic components of GABAergic inhibition. Copyright © 2013 Elsevier B.V. All rights reserved.

  8. Major Crop Species Show Differential Balance between Root Morphological and Physiological Responses to Variable Phosphorus Supply

    Science.gov (United States)

    Lyu, Yang; Tang, Hongliang; Li, Haigang; Zhang, Fusuo; Rengel, Zed; Whalley, William R.; Shen, Jianbo

    2016-01-01

    The relationship between root morphological and physiological responses to variable P supply in different plant species is poorly understood. We compared root morphological and physiological responses to P supply in seven crop species (Zea mays, Triticum aestivum, Brassica napus, Lupinus albus, Glycine max, Vicia faba, Cicer arietinum) treated with or without 100 mg P kg-1 in two soils (acidic and calcareous). Phosphorus deficiency decreased root length more in fibrous root species (Zea mays, Triticum aestivum, Brassica napus) than legumes. Zea mays and Triticum aestivum had higher root/shoot biomass ratio and Brassica napus had higher specific root length compared to legumes, whereas legumes (except soybean) had higher carboxylate exudation than fibrous root species. Lupinus albus exhibited the highest P-acquisition efficiency due to high exudation of carboxylates and acid phosphatases. Lupinus albus and Cicer arietinum depended mostly on root exudation (i.e., physiological response) to enhance P acquisition, whereas Zea mays, Triticum aestivum and Brassica napus had higher root morphology dependence, with Glycine max and Vicia faba in between. Principal component analysis using six morphological and six physiological responses identified root size and diameter as the most important morphological traits, whereas important physiological responses included carboxylate exudation, and P-acquisition and P-utilization efficiency followed by rhizosphere soil pH and acid phosphatase activity. In conclusion, plant species can be grouped on the basis of their response to soil P being primarily via root architectural or exudation plasticity, suggesting a potential benefit of crop-specific root-trait-based management to cope with variable soil P supply in sustainable grain production. PMID:28066491

  9. Manipulation of Cell Physiology Enables Gene Silencing in Well-differentiated Airway Epithelia

    Directory of Open Access Journals (Sweden)

    Sateesh Krishnamurthy

    2012-01-01

    Full Text Available The application of RNA interference-based gene silencing to the airway surface epithelium holds great promise to manipulate host and pathogen gene expression for therapeutic purposes. However, well-differentiated airway epithelia display significant barriers to double-stranded small-interfering RNA (siRNA delivery despite testing varied classes of nonviral reagents. In well-differentiated primary pig airway epithelia (PAE or human airway epithelia (HAE grown at the air–liquid interface (ALI, the delivery of a Dicer-substrate small-interfering RNA (DsiRNA duplex against hypoxanthine–guanine phosphoribosyltransferase (HPRT with several nonviral reagents showed minimal uptake and no knockdown of the target. In contrast, poorly differentiated cells (2–5-day post-seeding exhibited significant oligonucleotide internalization and target knockdown. This finding suggested that during differentiation, the barrier properties of the epithelium are modified to an extent that impedes oligonucleotide uptake. We used two methods to overcome this inefficiency. First, we tested the impact of epidermal growth factor (EGF, a known enhancer of macropinocytosis. Treatment of the cells with EGF improved oligonucleotide uptake resulting in significant but modest levels of target knockdown. Secondly, we used the connectivity map (Cmap database to correlate gene expression changes during small molecule treatments on various cells types with genes that change upon mucociliary differentiation. Several different drug classes were identified from this correlative assessment. Well-differentiated epithelia treated with DsiRNAs and LY294002, a PI3K inhibitor, significantly improved gene silencing and concomitantly reduced target protein levels. These novel findings reveal that well-differentiated airway epithelia, normally resistant to siRNA delivery, can be pretreated with small molecules to improve uptake of synthetic oligonucleotide and RNA interference (RNAi responses.

  10. Differential development of neuronal physiological responsiveness in two human neural stem cell lines.

    Science.gov (United States)

    Donato, Roberta; Miljan, Erik A; Hines, Susan J; Aouabdi, Sihem; Pollock, Kenneth; Patel, Sara; Edwards, Frances A; Sinden, John D

    2007-05-25

    Neural stem cells (NSCs) are powerful research tools for the design and discovery of new approaches to neurodegenerative disease. Overexpression of the myc family transcription factors in human primary cells from developing cortex and mesencephalon has produced two stable multipotential NSC lines (ReNcell VM and CX) that can be continuously expanded in monolayer culture. In the undifferentiated state, both ReNcell VM and CX are nestin positive and have resting membrane potentials of around -60 mV but do not display any voltage-activated conductances. As initially hypothesized, using standard methods (stdD) for differentiation, both cell lines can form neurons, astrocytes and oligodendrocytes according to immunohistological characteristics. However it became clear that this was not true for electrophysiological features which designate neurons, such as the firing of action potentials. We have thus developed a new differentiation protocol, designated 'pre-aggregation differentiation' (preD) which appears to favor development of electrophysiologically functional neurons and to lead to an increase in dopaminergic neurons in the ReNcell VM line. In contrast, the protocol used had little effect on the differentiation of ReNcell CX in which dopaminergic differentiation was not observed. Moreover, after a week of differentiation with the preD protocol, 100% of ReNcell VM featured TTX-sensitive Na+-channels and fired action potentials, compared to 25% after stdD. Currents via other voltage-gated channels did not appear to depend on the differentiation protocol. ReNcell CX did not display the same electrophysiological properties as the VM line, generating voltage-dependant K+ currents but no Na+ currents or action potentials under either stdD or preD differentiation. These data demonstrate that overexpression of myc in NSCs can be used to generate electrophysiologically active neurons in culture. Development of a functional neuronal phenotype may be dependent on parameters

  11. Differential development of neuronal physiological responsiveness in two human neural stem cell lines

    Directory of Open Access Journals (Sweden)

    Patel Sara

    2007-05-01

    Full Text Available Abstract Background Neural stem cells (NSCs are powerful research tools for the design and discovery of new approaches to neurodegenerative disease. Overexpression of the myc family transcription factors in human primary cells from developing cortex and mesencephalon has produced two stable multipotential NSC lines (ReNcell VM and CX that can be continuously expanded in monolayer culture. Results In the undifferentiated state, both ReNcell VM and CX are nestin positive and have resting membrane potentials of around -60 mV but do not display any voltage-activated conductances. As initially hypothesized, using standard methods (stdD for differentiation, both cell lines can form neurons, astrocytes and oligodendrocytes according to immunohistological characteristics. However it became clear that this was not true for electrophysiological features which designate neurons, such as the firing of action potentials. We have thus developed a new differentiation protocol, designated 'pre-aggregation differentiation' (preD which appears to favor development of electrophysiologically functional neurons and to lead to an increase in dopaminergic neurons in the ReNcell VM line. In contrast, the protocol used had little effect on the differentiation of ReNcell CX in which dopaminergic differentiation was not observed. Moreover, after a week of differentiation with the preD protocol, 100% of ReNcell VM featured TTX-sensitive Na+-channels and fired action potentials, compared to 25% after stdD. Currents via other voltage-gated channels did not appear to depend on the differentiation protocol. ReNcell CX did not display the same electrophysiological properties as the VM line, generating voltage-dependant K+ currents but no Na+ currents or action potentials under either stdD or preD differentiation. Conclusion These data demonstrate that overexpression of myc in NSCs can be used to generate electrophysiologically active neurons in culture. Development of a

  12. High Physiological Concentrations of Progesterone Reverse Estradiol-Mediated Changes in Differentiation and Functions of Bone Marrow Derived Dendritic Cells.

    Science.gov (United States)

    Xiu, Fangming; Anipindi, Varun C; Nguyen, Philip V; Boudreau, Jeanette; Liang, Hong; Wan, Yonghong; Snider, Denis P; Kaushic, Charu

    2016-01-01

    Female sex steroids, estradiol (E2) and progesterone (P4), play a key role in regulating immune responses in women, including dendritic cell (DC) development, and functions. Although the two hormones co-occur in the body of women throughout the reproductive years, no studies have explored their complex combinatorial effects on DCs, given their ability to regulate each other's actions. We examined murine bone marrow derived dendritic cells (BMDC) differentiation and functions, in the presence of a wide range of physiological concentrations of each hormone, as well as the combination of the two hormones. E2 (10(-12) to 10(-8)M) enhanced the differentiation of CD11b+CD11c+ DCs from BM precursor cells, and promoted the expression of CD40 and MHC Class-II, in a dose-dependent manner. In contrast, P4 (10(-9) to 10(-5)M) inhibited DC differentiation, but only at the highest concentrations. These effects on BMDCs were observed both in the presence or absence of LPS. When both hormones were combined, higher concentrations of P4, at levels seen in pregnancy (10(-6)M) reversed the E2 effects, regardless of the concentration of E2, especially in the absence of LPS. Functionally, antigen uptake was decreased and pro-inflammatory cytokines, IL-12, IL-1 and IL-6 production by CD11b+CD11c+ DCs, was increased in the presence of E2 and these effects were reversed by high concentrations of P4. Our results demonstrate the distinct effects of E2 and P4 on differentiation and functions of bone marrow myeloid DCs. The dominating effect of higher physiological concentrations of P4 provides insight into how DC functions could be modulated during pregnancy.

  13. Differential physiological responses and tolerance to potentially toxic elements in biodiesel tree Jatropha curcas.

    Science.gov (United States)

    Yamada, Minami; Malambane, Goitseone; Yamada, Satoshi; Suharsono, Sony; Tsujimoto, Hisashi; Moseki, Baleseng; Akashi, Kinya

    2018-01-26

    Environmental pollution by potentially toxic elements (PTEs) has become a serious problem with increasing industrialization and the disturbance of natural biogeochemical cycles. Jatropha is an oilseed-bearing shrub with high potential for biodiesel production in arid regions. In this study, we examined the physiological responses of this plant to five representative PTEs (Cd, Cr, Cu, Ni, and Zn) in a hydroponic culture. Application of higher concentrations of Cd and Zn led to severe leaf chlorosis, and Cd, Cu, and Ni treatments resulted in significant growth retardation. Higher enrichment of the applied PTEs in the shoots was observed for Zn- and Cd-treated plants, with the latter reaching 24-fold enrichment in plants exposed to 10 μM Cd, suggesting that Jatropha can cope with relatively higher internal concentrations of toxic Cd. Although Cd stress led to the disturbance of essential mineral homeostasis and photosynthesis, this induced an increase in thiol compounds in the roots, suggesting defensive responses of Jatropha to PTEs. This study showed that Jatropha exhibits distinct sensitivities and physiological responses to different PTEs. This study also provides basic knowledge for diagnosing the physiological status of Jatropha trees for potential dual use in afforestation and as a sustainable energy supply.

  14. A Simple Method for Decreasing the Liquid Junction Potential in a Flow-through-Type Differential pH Sensor Probe Consisting of pH-FETs by Exerting Spatiotemporal Control of the Liquid Junction

    Science.gov (United States)

    Yamada, Akira; Mohri, Satoshi; Nakamura, Michihiro; Naruse, Keiji

    2015-01-01

    The liquid junction potential (LJP), the phenomenon that occurs when two electrolyte solutions of different composition come into contact, prevents accurate measurements in potentiometry. The effect of the LJP is usually remarkable in measurements of diluted solutions with low buffering capacities or low ion concentrations. Our group has constructed a simple method to eliminate the LJP by exerting spatiotemporal control of a liquid junction (LJ) formed between two solutions, a sample solution and a baseline solution (BLS), in a flow-through-type differential pH sensor probe. The method was contrived based on microfluidics. The sensor probe is a differential measurement system composed of two ion-sensitive field-effect transistors (ISFETs) and one Ag/AgCl electrode. With our new method, the border region of the sample solution and BLS is vibrated in order to mix solutions and suppress the overshoot after the sample solution is suctioned into the sensor probe. Compared to the conventional method without vibration, our method shortened the settling time from over two min to 15 s and reduced the measurement error by 86% to within 0.060 pH. This new method will be useful for improving the response characteristics and decreasing the measurement error of many apparatuses that use LJs. PMID:25835300

  15. A simple method for decreasing the liquid junction potential in a flow-through-type differential pH sensor probe consisting of pH-FETs by exerting spatiotemporal control of the liquid junction.

    Science.gov (United States)

    Yamada, Akira; Mohri, Satoshi; Nakamura, Michihiro; Naruse, Keiji

    2015-04-01

    The liquid junction potential (LJP), the phenomenon that occurs when two electrolyte solutions of different composition come into contact, prevents accurate measurements in potentiometry. The effect of the LJP is usually remarkable in measurements of diluted solutions with low buffering capacities or low ion concentrations. Our group has constructed a simple method to eliminate the LJP by exerting spatiotemporal control of a liquid junction (LJ) formed between two solutions, a sample solution and a baseline solution (BLS), in a flow-through-type differential pH sensor probe. The method was contrived based on microfluidics. The sensor probe is a differential measurement system composed of two ion-sensitive field-effect transistors (ISFETs) and one Ag/AgCl electrode. With our new method, the border region of the sample solution and BLS is vibrated in order to mix solutions and suppress the overshoot after the sample solution is suctioned into the sensor probe. Compared to the conventional method without vibration, our method shortened the settling time from over two min to 15 s and reduced the measurement error by 86% to within 0.060 pH. This new method will be useful for improving the response characteristics and decreasing the measurement error of many apparatuses that use LJs.

  16. Blockage of progestin physiology disrupts ovarian differentiation in XX Nile tilapia (Oreochromis niloticus)

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Linyan; Luo, Feng; Fang, Xuelian [Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715 (China); Charkraborty, Tapas [South Ehime Fisheries Research Center, Ehime University, Ainan, 798-4206 (Japan); Wu, Limin; Wei, Jing [Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715 (China); Wang, Deshou, E-mail: wdeshou@swu.edu.cn [Key Laboratory of Freshwater Fish Reproduction and Development (Ministry of Education), Key Laboratory of Aquatic Science of Chongqing, School of Life Sciences, Southwest University, Chongqing, 400715 (China)

    2016-04-22

    Previous studies indicated that maturation inducing hormone, 17α, 20β-Dihydroxy-4-pregnen-3-one (DHP), probably through nuclear progestin receptor (Pgr), might be involved in spermatogenesis and oogenesis in fish. To further elucidate DHP actions in teleostean ovarian differentiation, we analyzed the expression of pgr in the ovary of Nile tilapia (Oreochromis niloticus), and performed RU486 (a synthetic Pgr antagonist) treatment in XX fish from 5 days after hatching (dah) to 120dah. Tilapia Pgr was abundantly expressed in the follicular cells surrounding oocytes at 30 and 90dah. Continuous RU486 treatment led to the blockage of oogenesis and masculinization of somatic cells in XX fish. Termination of RU486 treatment and maintenance in normal condition resulted in testicular differentiation, and estrogen compensation in RU486-treated XX fish successfully restored oogenesis. In RU486-treated XX fish, transcript levels of female dominant genes were significantly reduced, while male-biased genes were evidently augmented. Meanwhile, both germ cell mitotic and meiotic markers were substantially reduced. Consistently, estrogen production levels were significantly declined in RU486-treated XX fish. Taken together, our data further proved that DHP, possibly through Pgr, might be essential in the ovarian differentiation and estrogen production in fish. - Highlights: • DHP plays a critical role in early stage oogenesis of XX tilapia. • Blockage of DHP actions by RU486 treatment led to masculinization and/or sex reversal in XX tilapia. • Both DHP and estrogen are indispensable for ovarian differentiation.

  17. Differential response to ocean acidification in physiological traits of Concholepas concholepas populations

    Science.gov (United States)

    Lardies, Marco A.; Arias, María Belén; Poupin, María Josefina; Manríquez, Patricio H.; Torres, Rodrigo; Vargas, Cristian A.; Navarro, Jorge M.; Lagos, Nelson A.

    2014-07-01

    Phenotypic adaptation to environmental fluctuations frequently occurs by preexisting plasticity and its role as a major component of variation in physiological diversity is being widely recognized. Few studies have considered the change in phenotypic flexibility among geographic populations in marine calcifiers to ocean acidification projections, despite the fact that this type of study provides understanding about how the organism may respond to this chemical change in the ocean. We examined the geographic variation in CO2 seawater concentrations in the phenotype and in the reaction norm of physiological traits using a laboratory mesocosm approach with short-term acclimation in two contrasting populations (Antofagasta and Calfuco) of the intertidal snail Concholepas concholepas. Our results show that elevated pCO2 conditions increase standard metabolic rates in both populations of the snail juveniles, likely due to the higher energy cost of homeostasis. Juveniles of C. concholepas in the Calfuco (southern) population showed a lower increment of metabolic rate in high-pCO2 environments concordant with a lesser gene expression of a heat shock protein with respect to the Antofagasta (northern) population. Combined these results indicate a negative effect of ocean acidification on whole-organism functioning of C. concholepas. Finally, the significant Population × pCO2 level interaction in both studied traits indicates that there is variation between populations in response to high-pCO2 conditions.

  18. Physiological and molecular evidence of differential short-term heat tolerance in Mediterranean seagrasses

    Science.gov (United States)

    Marín-Guirao, Lazaro; Ruiz, Juan M.; Dattolo, Emanuela; Garcia-Munoz, Rocio; Procaccini, Gabriele

    2016-06-01

    The increase in extreme heat events associated to global warming threatens seagrass ecosystems, likely by affecting key plant physiological processes such as photosynthesis and respiration. Understanding species’ ability to acclimate to warming is crucial to better predict their future trends. Here, we study tolerance to warming in two key Mediterranean seagrasses, Posidonia oceanica and Cymodocea nodosa. Stress responses of shallow and deep plants were followed during and after short-term heat exposure in mesocosms by coupling photo-physiological measures with analysis of expression of photosynthesis and stress-related genes. Contrasting tolerance and capacity to heat acclimation were shown by shallow and deep P. oceanica ecotypes. While shallow plants acclimated through respiratory homeostasis and activation of photo-protective mechanisms, deep ones experienced photosynthetic injury and impaired carbon balance. This suggests that P. oceanica ecotypes are thermally adapted to local conditions and that Mediterranean warming will likely diversely affect deep and shallow meadow stands. On the other hand, contrasting mechanisms of heat-acclimation were adopted by the two species. P. oceanica regulates photosynthesis and respiration at the level of control plants while C. nodosa balances both processes at enhanced rates. These acclimation discrepancies are discussed in relation to inherent attributes of the two species.

  19. Pulmonary antioxidants exert differential protective effects against ...

    Indian Academy of Sciences (India)

    Unknown

    icosahedral bacteriophage ϕX174-RF DNA (Promega,. Southampton, UK) was selected as the optimum plasmid due to its size and sensitivity to oxidative damage. All control and test incubations were carried out according to the protocol of Greenwell et al (2002). Gels were imaged using the Syngene Genesnap program ...

  20. Pulmonary antioxidants exert differential protective effects against ...

    Indian Academy of Sciences (India)

    PM collections from both urban and industrial sites caused 50% oxidative degradation of DNA in vitro at concentrations as low as 12.9 ± 2.1 g ml–1 and 4.9 ± 0.9 mg ml–1 respectively. The primary source of this bioreactivity was found to be the soluble fraction of both particle collections. The coarser PM10–2.5 fraction also ...

  1. Physiological thermal limits predict differential responses of bees to urban heat-island effects.

    Science.gov (United States)

    Hamblin, April L; Youngsteadt, Elsa; López-Uribe, Margarita M; Frank, Steven D

    2017-06-01

    Changes in community composition are an important, but hard to predict, effect of climate change. Here, we use a wild-bee study system to test the ability of critical thermal maxima (CTmax, a measure of heat tolerance) to predict community responses to urban heat-island effects in Raleigh, NC, USA. Among 15 focal species, CTmax ranged from 44.6 to 51.3°C, and was strongly predictive of population responses to urban warming across 18 study sites (r(2) = 0.44). Species with low CTmax declined the most. After phylogenetic correction, solitary species and cavity-nesting species (bumblebees) had the lowest CTmax, suggesting that these groups may be most sensitive to climate change. Community responses to urban and global warming will likely retain strong physiological signal, even after decades of warming during which time lags and interspecific interactions could modulate direct effects of temperature. © 2017 The Author(s).

  2. An invader differentially affects leaf physiology of two natives across a gradient in diversity.

    Science.gov (United States)

    Kittelson, Pamela; Maron, John; Marler, Marilyn

    2008-05-01

    Little is known about how exotics influence the ecophysiology of co-occurring native plants or how invader impact on plant physiology may be mediated by community diversity or resource levels. We measured the effect of the widespread invasive forb spotted knapweed (Centaurea maculosa) on leaf traits (leaf dry matter content, specific leaf area, leaf nitrogen percentage, leaf C:N ratios, and delta13C as a proxy for water use efficiency) of two co-occurring native perennial grassland species, Monarda fistulosa (bee balm) and Koeleria macrantha (Junegrass). The impact of spotted knapweed was assessed across plots that varied in functional diversity and that either experienced ambient rainfall or received supplemental water. Impact was determined by comparing leaf traits between identical knapweed-invaded and noninvaded assemblages. Virtually all M. fistulosa leaf traits were affected by spotted knapweed. Knapweed impact, however, did not scale with its abundance; the impact of knapweed on M. fistulosa was similar across heavily invaded low-diversity assemblages and lightly invaded high-diversity assemblages. In uninvaded assemblages, M. fistulosa delta13C, leaf nitrogen, and C:N ratios were unaffected by native functional group richness, whereas leaf dry matter content significantly increased and specific leaf area significantly decreased across the diversity gradient. The effects of spotted knapweed on K. macrantha were weak; instead native functional group richness strongly affected K. macrantha leaf C:N ratio, delta13C, and specific leaf area, but not leaf dry matter content. Leaf traits for both species changed in response to spotted knapweed or functional richness, and in a manner that may promote slower biomass accumulation and efficient conservation of resources. Taken together, our results show that an invader can alter native plant physiology, but that these effects are not a simple function of how many invaders exist in the community.

  3. Prior Acute Mental Exertion in Exercise and Sport.

    Science.gov (United States)

    Silva-Júnior, Fernando Lopes E; Emanuel, Patrick; Sousa, Jordan; Silva, Matheus; Teixeira, Silmar; Pires, Flávio; Machado, Sérgio; Arias-Carrion, Oscar

    2016-01-01

    Mental exertion is a psychophysiological state caused by sustained and prolonged cognitive activity. The understanding of the possible effects of acute mental exertion on physical performance, and their physiological and psychological responses are of great importance for the performance of different occupations, such as military, construction workers, athletes (professional or recreational) or simply practicing regular exercise, since these occupations often combine physical and mental tasks while performing their activities. However, the effects of implementation of a cognitive task on responses to aerobic exercise and sports are poorly understood. Our narrative review aims to provide information on the current research related to the effects of prior acute mental fatigue on physical performance and their physiological and psychological responses associated with exercise and sports. The literature search was conducted using the databases PubMed, ISI Web of Knowledge and PsycInfo using the following terms and their combinations: "mental exertion", "mental fatigue", "mental fatigue and performance", "mental exertion and sports" "mental exertion and exercise". We concluded that prior acute mental exertion affects effectively the physiological and psychophysiological responses during the cognitive task, and performance in exercise. Additional studies involving prior acute mental exertion, exercise/sports and physical performance still need to be carried out in order to analyze the physiological, psychophysiological and neurophysiological responses subsequently to acute mental exertion in order to identify cardiovascular factors, psychological, neuropsychological associates.

  4. Cardiovascular Fitness and the Psychophysics of Perceived Exertion.

    Science.gov (United States)

    Mihevic, Patricia M.

    1983-01-01

    The perceptual responses of individuals at different levels of physical fitness to absolute exercise intensities were compared. Perceived exertion, as measured by the Rating of Perceived Exertion scale, did not discriminate between subjects who were physically fit and those who were not, despite differences in physiological strain. (Author/PP)

  5. Differential Physiological Responses of Portuguese Bread Wheat (Triticum aestivum L. Genotypes under Aluminium Stress

    Directory of Open Access Journals (Sweden)

    Ana Luísa Garcia-Oliveira

    2016-12-01

    Full Text Available The major limitation of cereal production in acidic soils is aluminium (Al phytotoxicity which inhibits root growth. Recent evidence indicates that different genotypes within the same species have evolved different mechanisms to cope with this stress. With these facts in mind, root responses of two highly Al tolerant Portuguese bread wheat genotypes—Barbela 7/72/92 and Viloso mole—were investigated along with check genotype Anahuac (Al sensitive, using different physiological and histochemical assays. All the assays confirmed that Barbela 7/72/92 is much more tolerant to Al phytotoxicity than Viloso Mole. Our results demonstrate that the greater tolerance to Al phytotoxicity in Barbela 7/72/92 than in Viloso Mole relies on numerous factors, including higher levels of organic acid (OAs efflux, particularly citrate efflux. This might be associated with the lower accumulation of Al in the root tips, restricting the Al-induced lipid peroxidation and the consequent plasma membrane integrity loss, thus allowing better root regrowth under Al stress conditions. Furthermore, the presence of root hairs in Barbela 7/72/92 might also help to circumvent Al toxicity by facilitating a more efficient uptake of water and nutrients, particularly under Al stress on acid soils. In conclusion, our findings confirmed that Portuguese bread wheat genotype Barbela 7/72/92 represents an alternative source of Al tolerance in bread wheat and could potentially be used to improve the wheat productivity in acidic soils.

  6. Fish gut microbiota analysis differentiates physiology and behavior of invasive Asian carp and indigenous American fish

    Science.gov (United States)

    Ye, Lin; Amberg, Jon J.; Chapman, Duane C.; Gaikowski, Mark P.; Liu, Wen-Tso

    2014-01-01

    Gut microbiota of invasive Asian silver carp (SVCP) and indigenous planktivorous gizzard shad (GZSD) in Mississippi river basin were compared using 16S rRNA gene pyrosequencing. Analysis of more than 440 000 quality-filtered sequences obtained from the foregut and hindgut of GZSD and SVCP revealed high microbial diversity in these samples. GZSD hindgut (GZSD_H) samples (n=23) with >7000 operational taxonomy units (OTUs) exhibited the highest alpha-diversity indices followed by SVCP foregut (n=15), GZSD foregut (n=9) and SVCP hindgut (SVCP_H) (n=24). UniFrac distance-based non-metric multidimensional scaling (NMDS) analysis showed that the microbiota of GZSD_H and SVCP_H were clearly separated into two clusters: samples in the GZSD cluster were observed to vary by sampling location and samples in the SVCP cluster by sampling date. NMDS further revealed distinct microbial community between foregut to hindgut for individual GZSD and SVCP. Cyanobacteria, Proteobacteria, Actinobacteria and Bacteroidetes were detected as the predominant phyla regardless of fish or gut type. The high abundance of Cyanobacteria observed was possibly supported by their role as the fish’s major food source. Furthermore, unique and shared OTUs and OTUs in each gut type were identified, three OTUs from the order Bacteroidales, the genus Bacillariophyta and the genus Clostridium were found significantly more abundant in GZSD_H (14.9–22.8%) than in SVCP_H (0.13–4.1%) samples. These differences were presumably caused by the differences in the type of food sources including bacteria ingested, the gut morphology and digestion, and the physiological behavior between GZSD and SVCP.

  7. Growth differentiation factor 5 is a key physiological regulator of dendrite growth during development.

    Science.gov (United States)

    Osório, Catarina; Chacón, Pedro J; Kisiswa, Lilian; White, Matthew; Wyatt, Sean; Rodríguez-Tébar, Alfredo; Davies, Alun M

    2013-12-01

    Dendrite size and morphology are key determinants of the functional properties of neurons. Here, we show that growth differentiation factor 5 (GDF5), a member of the bone morphogenetic protein (BMP) subclass of the transforming growth factor β superfamily with a well-characterised role in limb morphogenesis, is a key regulator of the growth and elaboration of pyramidal cell dendrites in the developing hippocampus. Pyramidal cells co-express GDF5 and its preferred receptors, BMP receptor 1B and BMP receptor 2, during development. In culture, GDF5 substantially increased dendrite, but not axon, elongation from these neurons by a mechanism that depends on activation of SMADs 1/5/8 and upregulation of the transcription factor HES5. In vivo, the apical and basal dendritic arbours of pyramidal cells throughout the hippocampus were markedly stunted in both homozygous and heterozygous Gdf5 null mutants, indicating that dendrite size and complexity are exquisitely sensitive to the level of endogenous GDF5 synthesis.

  8. Differential roles of breakfast and supper in rats of a daily three-meal schedule upon circadian regulation and physiology.

    Science.gov (United States)

    Wu, Tao; Sun, Lu; ZhuGe, Fen; Guo, Xichao; Zhao, Zhining; Tang, Ruiqi; Chen, Qinping; Chen, Lin; Kato, Hisanori; Fu, Zhengwei

    2011-12-01

    The timing of meals has been suggested to play an important role in circadian regulation and metabolic health. Three meals a day is a well-established human feeding habit, which in today's lifestyle may or may not be followed. The aim of this study was to test whether the absence of breakfast or supper significantly affects the circadian system and physiological function. The authors developed a rat model for their daily three meals study, whereby animals were divided into three groups (three meals, TM; no first meal, NF; no last meal, NL) all fed with the same amount of food every day. Rats in the NF group displayed significantly decreased levels of plasma triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and glucose in the activity phase, accompanied by delayed circadian phases of hepatic peripheral clock and downstream metabolic genes. Rats in the NL group showed lower concentration of plasma TC, HDL-C, and glucose in the rest phase, plus reduced adipose tissue accumulation and body weight gain. Real-time polymerase chain reaction (PCR) analysis indicated an attenuated rhythm in the food-entraining pathway, including down-regulated expression of the clock genes Per2, Bmal1, and Rev-erbα, which may further contribute to the delayed and decreased expression of FAS in lipogenesis in this group. Our findings are consistent with the conclusion that the daily first meal determines the circadian phasing of peripheral clocks, such as in the liver, whereas the daily last meal tightly couples to lipid metabolism and adipose tissue accumulation, which suggests differential physiological effects and function of the respective meal timings.

  9. Physiological mechanism of population differentiation in shade-avoidance responses between woodland and clearing genotypes of Impatiens capensis.

    Science.gov (United States)

    von Wettberg, Eric J; Schmitt, Johanna

    2005-05-01

    Forest understory plants often respond less intensely to reduced ratios of red to far red (R : FR) light, an important signal of foliage shade, than conspecific or congeneric plants from open-canopy sites. Reduced responsiveness to low R : FR in plants from closed-canopy sites could be caused by two physiological mechanisms. First, closed-canopy plants could have less sensitive shade-avoidance responses to low R : FR. Second, the high irradiance response to FR (FR-HIR), which allows seedling de-etiolation under low R : FR, might be stronger or persist longer after de-etiolation in closed-canopy plants, thus counteracting shade-avoidance responses to low R : FR. These hypotheses were tested using diodes that emit red and far-red light to distinguish the responses to altered R : FR of genotypes of Impatiens capensis collected from a pair of open- and closed-canopy populations that have previously been shown to differ in sensitivity to R : FR. Genotypes from the open-canopy environment exhibited typical shade-avoidance responses, elongating in response to supplemental FR. However, genotypes from the closed-canopy environment responded to supplemental FR by elongating less than under ambient control conditions, indicating a persistent FR-HIR. Thus, the observed population differentiation in response to low R : FR may be linked to population differences in FR-HIR.

  10. Exertional leg pain: teasing out arterial entrapments.

    Science.gov (United States)

    Pham, Thomas T; Kapur, Rahul; Harwood, Marc I

    2007-12-01

    Vascular causes of exertional lower extremity pain are relatively rare, but may be the answer in athletes refractory to treatment for the more common overuse syndromes of the lower extremities. It is important to differentiate these vascular causes from chronic exertional compartment syndrome (CECS), medial tibial stress syndrome (MTSS), and stress fractures in order to develop appropriate treatment plans, avoid complications, and return athletes to play expeditiously. Important vascular etiologies to be considered are popliteal artery entrapment syndrome (PAES), endofibrotic disease, popliteal artery aneurysm, cystic adventitial disease, and peripheral arterial dissections. The diagnostic workup involves angiography or noninvasive vascular studies such as Doppler ultrasound or magnetic resonance angiography in both the neutral and provocative positions. Treatment of these vascular abnormalities typically involves surgical correction of the vascular anomaly.

  11. The full spectrum of physiological oxygen tensions and step-changes in oxygen tension affects the neural differentiation of mouse embryonic stem cells.

    Science.gov (United States)

    Mondragon-Teran, Paul; Baboo, Jasmin Z; Mason, Chris; Lye, Gary J; Veraitch, Farlan S

    2011-01-01

    The beneficial impact of lowering oxygen tension to physiological levels has been demonstrated in a number of stem cell differentiation protocols. The majority of these studies compare normal laboratory oxygen tension with one physiological condition (typically 2-5% O(2) ). In this article, we investigated whether the full spectrum of physiological oxygen tensions (0-20% O(2) ) and step-changes in oxygen tension could enhance the production of neural populations from of embryonic stem cells (ESCs). We used a model system for the conversion of mouse ESCs into cells expressing one neuroectoderm stem cell marker (nestin) and two neural markers (βIII tubulin and microtubule-associated protein (MAP2)). 4-10% O(2) was associated with large increases in the total production of viable cells and the highest number of cells expressing Nestin, βIII tubulin, and MAP2. However, 4-10% O(2) also caused a reduction in the percentage of cells expressing all three markers. Step changes in oxygen tension at the mid-point of the differentiation process affected the total production of viable cells and the percentage of cells expressing all three markers. We found that the initial oxygen tension and the magnitude of the step-change were critical variables. A step increase from 0 to 2% O(2) mid-way through the protocol resulted in the highest percentage of cells expressing βIII tubulin (86.5%). In conclusion, we have demonstrated that the full spectrum of physiological oxygen tensions and step changes in oxygen tension represent a powerful tool for the optimisation of neural differentiation processes. Copyright © 2011 American Institute of Chemical Engineers (AIChE).

  12. Physiological and hypoxic oxygen concentration differentially regulates human c-Kit+ cardiac stem cell proliferation and migration.

    Science.gov (United States)

    Bellio, Michael A; Rodrigues, Claudia O; Landin, Ana Marie; Hatzistergos, Konstantinos E; Kuznetsov, Jeffim; Florea, Victoria; Valasaki, Krystalenia; Khan, Aisha; Hare, Joshua M; Schulman, Ivonne Hernandez

    2016-12-01

    Cardiac stem cells (CSCs) are being evaluated for their efficacy in the treatment of heart failure. However, numerous factors impair the exogenously delivered cells' regenerative capabilities. Hypoxia is one stress that contributes to inadequate tissue repair. Here, we tested the hypothesis that hypoxia impairs cell proliferation, survival, and migration of human CSCs relative to physiological and room air oxygen concentrations. Human endomyocardial biopsy-derived CSCs were isolated, selected for c-Kit expression, and expanded in vitro at room air (21% O2). To assess the effect on proliferation, survival, and migration, CSCs were transferred to physiological (5%) or hypoxic (0.5%) O2 concentrations. Physiological O2 levels increased proliferation (P air and hypoxia, a significant reduction of β-galactosidase activity (-4,203 fluorescent units, P air and hypoxia, and treatment with mesenchymal stem cell-conditioned media rescued CSC migration under hypoxia to levels comparable to physiological O2 migration (2-fold, P air may diminish cell regenerative potential. This study provides novel insights into the modulatory effects of O2 concentration on CSC biology and has important implications for refining stem cell therapies. Copyright © 2016 the American Physiological Society.

  13. The inhibition of cultured myoblast differentiation by the simian virus 40 large T antigen occurs after myogenin expression and Rb up-regulation and is not exerted by transformation-competent cytoplasmic mutants.

    OpenAIRE

    Tedesco, D; Caruso, M; Fischer-Fantuzzi, L; Vesco, C

    1995-01-01

    We have investigated the mechanism by which the simian virus 40 large T antigen (SVLT) interferes with the differentiation of C2 myoblasts. SVLT mutants, defective either in the Rb binding site, near the N-terminal end, in a region that affects binding to p53, or in the nuclear transport signal, were also employed to determine whether the interference was especially dependent on these functional domains. It was found that wild-type (wt) SVLT strongly inhibited the terminal differentiation of ...

  14. The inhibition of cultured myoblast differentiation by the simian virus 40 large T antigen occurs after myogenin expression and Rb up-regulation and is not exerted by transformation-competent cytoplasmic mutants.

    Science.gov (United States)

    Tedesco, D; Caruso, M; Fischer-Fantuzzi, L; Vesco, C

    1995-11-01

    We have investigated the mechanism by which the simian virus 40 large T antigen (SVLT) interferes with the differentiation of C2 myoblasts. SVLT mutants, defective either in the Rb binding site, near the N-terminal end, in a region that affects binding to p53, or in the nuclear transport signal, were also employed to determine whether the interference was especially dependent on these functional domains. It was found that wild-type (wt) SVLT strongly inhibited the terminal differentiation of mouse C2 myoblasts, but this arrest occurred only after the synthesis of myogenin, an initial step in biochemical differentiation. Neither the synthesis nor some basic activities of MyoD appeared to be affected by wt SVLT. In these transformants, mitogen depletion elicited an increase in the Rb level comparable to that in normal C2 cells; wt SVLT, however, promoted the phosphorylation of a large part of the induced Rb. Mutations affecting nuclear transport were far more critical for the ability to interfere with myogenic differentiation than were those affecting the transforming potential; cytoplasmic SVLT expression was fully compatible with the terminal differentiation of C2 cells, despite enabling them to grow in semisolid medium, thus showing that the myogenesis-inhibiting property can be dissociated from transforming competence. The remaining SVLT mutants presented different degrees of ability to inhibit differentiation (as shown by the expression of tissue-specific markers in transformants). The inhibiting mutants, including the Rb binding site mutant, were able to promote a higher state of Rb phosphorylation than that observed in either normal cells or cytoplasmic-SVLT transformants.

  15. The mechanisms underlying sexual differentiation of behavior and physiology in mammals and birds: relative contributions of sex steroids and sex chromosomes

    Directory of Open Access Journals (Sweden)

    Fumihiko eMaekawa

    2014-08-01

    Full Text Available From a classical viewpoint, sex-specific behavior and physiological functions as well as the brain structures of mammals such as rats and mice, have been thought to be influenced by perinatal sex steroids secreted by the gonads. Sex steroids have also been thought to affect the differentiation of the sex-typical behavior of a few members of the avian order Galliformes, including the Japanese quail and chickens, during their development in ovo. However, recent mammalian studies that focused on the artificial shuffling or knockout of the sex-determining gene, Sry, have revealed that sex chromosomal effects may be associated with particular types of sex-linked differences such as aggression levels, social interaction, and autoimmune diseases, independently of sex steroid-mediated effects. In addition, studies on naturally occurring, rare phenomena such as gynandromorphic birds and experimentally constructed chimeras in which the composition of sex chromosomes in the brain differs from that in the other parts of the body, indicated that sex chromosomes play certain direct roles in the sex-specific differentiation of the gonads and the brain. In this article, we review the relative contributions of sex steroids and sex chromosomes in the determination of brain functions related to sexual behavior and reproductive physiology in mammals and birds.

  16. Mathematical physiology

    CERN Document Server

    Sneyd, James

    2009-01-01

    There has been a long history of interaction between mathematics and physiology. This book looks in detail at a wide selection of mathematical models in physiology, showing how physiological problems can be formulated and studied mathematically, and how such models give rise to interesting and challenging mathematical questions. With its coverage of many recent models it gives an overview of the field, while many older models are also discussed, to put the modern work in context. In this second edition the coverage of basic principles has been expanded to include such topics as stochastic differential equations, Markov models and Gibbs free energy, and the selection of models has also been expanded to include some of the basic models of fluid transport, respiration/perfusion, blood diseases, molecular motors, smooth muscle, neuroendrocine cells, the baroreceptor loop, turboglomerular oscillations, blood clotting and the retina. Owing to this extensive coverage, the second edition is published in two volumes. ...

  17. Intraspecific variation in physiological condition of reef-building corals associated with differential levels of chronic disturbance.

    Directory of Open Access Journals (Sweden)

    Chiara Pisapia

    Full Text Available Even in the absence of major disturbances (e.g., cyclones, bleaching, corals are subject to high levels of partial or whole-colony mortality, often caused by chronic and small-scale disturbances. Depending on levels of background mortality, these chronic disturbances may undermine individual fitness and have significant consequences on the ability of colonies to withstand subsequent acute disturbances or environmental change. This study quantified intraspecific variations in physiological condition (measured based on total lipid content and zooxanthellae density through time in adult colonies of two common and widespread coral species (Acropora spathulata and Pocillopora damicornis, subject to different levels of biological and physical disturbances along the most disturbed reef habitat, the crest. Marked intraspecific variation in the physiological condition of A. spathulata was clearly linked to differences in local disturbance regimes and habitat. Specifically, zooxanthellae density decreased (r2 = 26, df = 5,42, p<0.02, B =  -121255, p = 0.03 and total lipid content increased (r2 = 14, df = 5,42, p = 0.01, B = 0.9, p = 0.01 with increasing distance from exposed crests. Moreover, zooxanthellae density was strongly and negatively correlated with the individual level of partial mortality (r2 = 26, df = 5,42, p<0.02, B =  -7386077, p = 0.01. Conversely, P. damicornis exhibited very limited intraspecific variation in physiological condition, despite marked differences in levels of partial mortality. This is the first study to relate intraspecific variation in the condition of corals to localized differences in chronic disturbance regimes. The next step is to ascertain whether these differences have further ramifications for susceptibility to periodic acute disturbances, such as climate-induced coral bleaching.

  18. Intraspecific variation in physiological condition of reef-building corals associated with differential levels of chronic disturbance.

    Science.gov (United States)

    Pisapia, Chiara; Anderson, Kristen; Pratchett, Morgan S

    2014-01-01

    Even in the absence of major disturbances (e.g., cyclones, bleaching), corals are subject to high levels of partial or whole-colony mortality, often caused by chronic and small-scale disturbances. Depending on levels of background mortality, these chronic disturbances may undermine individual fitness and have significant consequences on the ability of colonies to withstand subsequent acute disturbances or environmental change. This study quantified intraspecific variations in physiological condition (measured based on total lipid content and zooxanthellae density) through time in adult colonies of two common and widespread coral species (Acropora spathulata and Pocillopora damicornis), subject to different levels of biological and physical disturbances along the most disturbed reef habitat, the crest. Marked intraspecific variation in the physiological condition of A. spathulata was clearly linked to differences in local disturbance regimes and habitat. Specifically, zooxanthellae density decreased (r2 = 26, df = 5,42, p<0.02, B =  -121255, p = 0.03) and total lipid content increased (r2 = 14, df = 5,42, p = 0.01, B = 0.9, p = 0.01) with increasing distance from exposed crests. Moreover, zooxanthellae density was strongly and negatively correlated with the individual level of partial mortality (r2 = 26, df = 5,42, p<0.02, B =  -7386077, p = 0.01). Conversely, P. damicornis exhibited very limited intraspecific variation in physiological condition, despite marked differences in levels of partial mortality. This is the first study to relate intraspecific variation in the condition of corals to localized differences in chronic disturbance regimes. The next step is to ascertain whether these differences have further ramifications for susceptibility to periodic acute disturbances, such as climate-induced coral bleaching.

  19. Comparative Metabolomic Analyses of Ipomoea lacunosa Biotypes with Contrasting Glyphosate Tolerance Captures Herbicide-Induced Differential Perturbations in Cellular Physiology.

    Science.gov (United States)

    Maroli, Amith S; Nandula, Vijay K; Duke, Stephen O; Gerard, Patrick; Tharayil, Nishanth

    2018-02-16

    Glyphosate-tolerant Ipomoea lacunosa is emerging as a problematic weed in the southeastern United States. Metabolomic profiling was conducted to examine the innate physiology and the glyphosate induced perturbations in two biotypes of I. lacunosa (WAS and QUI) that had contrasting glyphosate tolerance. Compared to the less tolerant QUI-biotype, the innate metabolism of the more tolerant WAS-biotype was characterized by a higher abundance of amino acids, and pyruvate; whereas the sugar profile of the QUI biotype was dominated by the transport sugar sucrose. Glyphosate application (80 g ae/ha) caused similar shikimate accumulation in both biotypes. Compared to QUI, in WAS, the content of aromatic amino acids was less affected by glyphosate treatment, and the content of Ala, Val, Ile, and Pro increased. However, the total sugars decreased by ∼75% in WAS, compared to ∼50% decrease in QUI. The innate, higher proportional abundance, of the transport-sugar sucrose in QUI coud partly explain the higher translocation and greater sensitivity of this biotype to glyphosate. The decrease in sugars, accompanied by an increase in amino acids could delay feedback regulation of upstream enzymes of the shikimate acid pathway in WAS, which could contribute to a greater glyphosate tolerance. Our study, through a metabolomics approach, provides complementary data that elucidates the cellular physiology of herbicide tolerance in Ipomoea lacunosa biotypes.

  20. T1 and T2 mapping for early diagnosis of dilated non-ischaemic cardiomyopathy in middle-aged patients and differentiation from normal physiological adaptation.

    Science.gov (United States)

    Mordi, Ify; Carrick, David; Bezerra, Hiram; Tzemos, Nikolaos

    2016-07-01

    The differential diagnosis of patients with early non-ischaemic dilated cardiomyopathy (DCM) and those with physiological adaptation to exercise ('athlete's heart') may be difficult as many of the morphological adaptations are shared in the two conditions. Increased physical fitness is becoming more common in later adulthood, a group in whom there may be even more diagnostic difficulty. We hypothesized that tissue characterization using cardiovascular magnetic resonance (CMR) T1 and T2 mapping would be able to differentiate between patients with left ventricular (LV) dilatation due to early DCM and exercisers. Fifty-eight middle-aged males [21 healthy controls, 21 males with a history of aerobic exercise and LV ejection fraction (LVEF) 45-55%, and 16 patients with DCM and LVEF 45-55%] underwent a CMR protocol including T1 and T2 mapping and calculation of extracellular volume (ECV) using a 1.5 T MRI scanner. Native T1, ECV, and T2 relaxation times were significantly increased in DCM patients compared with controls (native T1 1017 ± 42 vs. 952 ± 31 ms, P T1 957 ± 32 ms, P T1 gave the best differentiation between exercisers and sedentary patients with early DCM (area under the curve 0.91). T1 and T2 mapping are potentially useful tools for differentiating between athlete's heart and patients with early DCM, and could be used whenever differentiation between these two phenotypes is inconclusive using standard imaging techniques. Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.

  1. Does mental exertion alter maximal muscle activation?

    Directory of Open Access Journals (Sweden)

    Vianney eRozand

    2014-09-01

    Full Text Available Mental exertion is known to impair endurance performance, but its effects on neuromuscular function remain unclear. The purpose of this study was to test the hypothesis that mental exertion reduces torque and muscle activation during intermittent maximal voluntary contractions of the knee extensors. Ten subjects performed in a randomized order three separate mental exertion conditions lasting 27 minutes each: i high mental exertion (incongruent Stroop task, ii moderate mental exertion (congruent Stroop task, iii low mental exertion (watching a movie. In each condition, mental exertion was combined with ten intermittent maximal voluntary contractions of the knee extensor muscles (one maximal voluntary contraction every 3 minutes. Neuromuscular function was assessed using electrical nerve stimulation. Maximal voluntary torque, maximal muscle activation and other neuromuscular parameters were similar across mental exertion conditions and did not change over time. These findings suggest that mental exertion does not affect neuromuscular function during intermittent maximal voluntary contractions of the knee extensors.

  2. PHYSIOLOGICAL ONTOGENY : A. CHICKEN EMBRYOS. VI. DIFFERENTIATION IN THE CHICKEN EMBRYO HEART FROM THE POINT OF VIEW OF STIMULUS PRODUCTION.

    Science.gov (United States)

    Cohn, A E

    1925-08-31

    In these experiments we have shown that, with the technique adopted, differences in behavior are exhibited by fragments of the heart taken from different localities. The different localities behave in a more or less uniform manner. The pace-making function, for instance, is found at first throughout the cardiac tube but later it is restricted and comes to reside in a special small area at the back of the right auricle near the center. The pace-making system is able to develop a rate comparable to that shown by the whole intact heart, irrespective of the size of the fragment in which it is contained. Later, under the circumstances of the study, the ventricular structures lose the power of spontaneous contraction, and later still, the auricular ones also. It need scarcely be pointed out, however, that this loss refers only to the function of pace making. In its place, the various localities of the heart undoubtedly take on other capabilities. This is what is meant after all by differentiation. The question whether the pace-making and conduction systems reside in the remains of primitive portions of the cardiac tube in an undifferentiated form, or whether on the other hand these primitive portions develop into differentiated structures which preside over these functions may be reviewed afresh. Obviously the tube in its early state possesses these functions; obviously also the major part of the heart loses them during the course of development. A knowledge of the changes in form paralleling changes in function would have great interest. On this phase of the problem we hope to report later. On the basis of these observations, differentiation from the point of view of stimulus production may be viewed perhaps in this manner. Pace making, the conduction of impulses, and contraction are the primitive functions of the tube. As the tube develops into the adult structure, pace making and conduction are supposedly served by tissues resembling in structure the original ones

  3. Human Breast Milk and Infant Formulas Differentially Modify the Intestinal Microbiota in Human Infants and Host Physiology in Rats.

    Science.gov (United States)

    Liu, Zhenmin; Roy, Nicole C; Guo, Yanhong; Jia, Hongxin; Ryan, Leigh; Samuelsson, Linda; Thomas, Ancy; Plowman, Jeff; Clerens, Stefan; Day, Li; Young, Wayne

    2016-02-01

    In the absence of human breast milk, infant and follow-on formulas can still promote efficient growth and development. However, infant formulas can differ in their nutritional value. The objective of this study was to compare the effects of human milk (HM) and infant formulas in human infants and a weanling rat model. In a 3 wk clinical randomized controlled trial, babies (7- to 90-d-old, male-to-female ratio 1:1) were exclusively breastfed (BF), exclusively fed Synlait Pure Canterbury Stage 1 infant formula (SPCF), or fed assorted standard formulas (SFs) purchased by their parents. We also compared feeding HM or SPCF in weanling male Sprague-Dawley rats for 28 d. We examined the effects of HM and infant formulas on fecal short chain fatty acids (SCFAs) and bacterial composition in human infants, and intestinal SCFAs, the microbiota, and host physiology in weanling rats. Fecal Bifidobacterium concentrations (mean log copy number ± SEM) were higher (P = 0.003) in BF (8.17 ± 0.3) and SPCF-fed infants (8.29 ± 0.3) compared with those fed the SFs (6.94 ± 0.3). Fecal acetic acid (mean ± SEM) was also higher (P = 0.007) in the BF (5.5 ± 0.2 mg/g) and SPCF (5.3 ± 2.4 mg/g) groups compared with SF-fed babies (4.3 ± 0.2 mg/g). Colonic SCFAs did not differ between HM- and SPCF-fed rats. However, cecal acetic acid concentrations were higher (P = 0.001) in rats fed HM (42.6 ± 2.6 mg/g) than in those fed SPCF (30.6 ± 0.8 mg/g). Cecal transcriptome, proteome, and plasma metabolite analyses indicated that the growth and maturation of intestinal tissue was more highly promoted by HM than SPCF. Fecal bacterial composition and SCFA concentrations were similar in babies fed SPCF or HM. However, results from the rat study showed substantial differences in host physiology between rats fed HM and SPCF. This trial was registered at Shanghai Jiào tong University School of Medicine as XHEC-C-2012-024. © 2016 American Society for Nutrition.

  4. Parent-child relationship, temperament, and physiological reactions to fear-inducing film clips: further evidence for differential susceptibility.

    Science.gov (United States)

    Gilissen, Renske; Bakermans-Kranenburg, Marian J; van IJzendoorn, Marinus H; van der Veer, René

    2008-03-01

    Recent studies have supported the intriguing hypothesis that highly reactive infants are most susceptible to the effect of parenting. This study replicates and extends an earlier study on 4-year-olds concerning higher susceptibility of more fearful children to the quality of their relationships with their mothers, as shown by their physiological reactions to fear-inducing film clips. Two groups of children (4- and 7-year-olds) were shown the same fear-inducing and neutral film clips. During the film clips, their skin conductance and heart rate variability were measured. Both 4- and 7-year-olds responded to the fear-inducing film clips with increases in skin conductance and decreases in heart rate variability. A secure relationship affected the reactivity to fearful stimuli in temperamentally more fearful children but not in less fearful children irrespective of children's ages. Our findings add to the growing literature showing that children high in negative emotion are more susceptible to positive as well as negative rearing influences for better and for worse.

  5. Morphology and cardiac physiology are differentially affected by temperature in developing larvae of the marine fish mahi-mahi (Coryphaena hippurus

    Directory of Open Access Journals (Sweden)

    Prescilla Perrichon

    2017-06-01

    Full Text Available Cardiovascular performance is altered by temperature in larval fishes, but how acute versus chronic temperature exposures independently affect cardiac morphology and physiology in the growing larva is poorly understood. Consequently, we investigated the influence of water temperature on cardiac plasticity in developing mahi-mahi. Morphological (e.g. standard length, heart angle and physiological cardiac variables (e.g. heart rate fH, stroke volume, cardiac output were recorded under two conditions by imaging: (i under acute temperature exposure where embryos were reared at 25°C up to 128 h post-fertilization (hpf and then acutely exposed to 25 (rearing temperature, 27 and 30°C; and (ii at two rearing (chronic temperatures of 26 and 30°C and performed at 32 and 56 hpf. Chronic elevated temperature improved developmental time in mahi-mahi. Heart rates were 1.2–1.4-fold higher under exposure of elevated acute temperatures across development (Q10≥2.0. Q10 for heart rate in acute exposure was 1.8-fold higher compared to chronic exposure at 56 hpf. At same stage, stroke volume was temperature independent (Q10∼1.0. However, larvae displayed higher stroke volume later in stage. Cardiac output in developing mahi-mahi is mainly dictated by chronotropic rather than inotropic modulation, is differentially affected by temperature during development and is not linked to metabolic changes.

  6. The role of echocardiography in the evaluation of cardiac re-modelling and differentiation between physiological and pathological hypertrophy in teenagers engaged in competitive amateur sports.

    Science.gov (United States)

    Sulovic, Ljiljana S; Mahmutovic, Meho; Lazic, Snezana; Sulovic, Nenad

    2017-05-01

    Aims "Athlete's heart" is a cardiac adaptation to long-term intensive training. The aims of this study were to show the prevalence of left ventricular hypertrophy in teenagers who participate in sports, to define the different types of cardiac re-modelling, and to differentiate between physiological and pathological hypertrophy. Echocardiographic measurements were obtained by M-mode, two dimensional, and Doppler techniques of participants from sports and control groups. The echocardiographic examinations included 100 healthy teenagers taking part in dynamic sports such as football and basketball and 100 healthy teenagers taking part in static sports such as karate and judo. The control group (n=100) included healthy, sedentary teenagers. Sports participants had significantly higher left ventricular mass when compared with the control group, (p0.05). Respondents from both groups had E/A ratios (transmitral flow velocity ratio)>1, preserved diastolic function, and statistically they did not differ from the control group. Echocardiographic parameters show that physiological hypertrophy and cardiac re-modelling are present in teenagers who play sports. Unexpectedly, the prevalence of concentric and eccentric types of re-modelling is equally possible in the group of static sports participants.

  7. Differential responses of grapevine rootstocks to water stress are associated with adjustments in fine root hydraulic physiology and suberization

    Science.gov (United States)

    Barrios-Masias, F.H.; Knipfer, T.; McElrone, A.J.

    2015-01-01

    Water deficits are known to alter fine root structure and function, but little is known about how these responses contribute to differences in drought resistance across grapevine rootstocks. The ways in which water deficit affects root anatomical and physiological characteristics were studied in two grapevine rootstocks considered as low–medium (101-14Mgt) and highly (110R) drought resistant. Rootstocks were grown under prolonged and repeated drying cycles or frequent watering (‘dry’ and ‘wet’ treatments, respectively), and the following parameters were evaluated: root osmotic and hydrostatic hydraulic conductivity (Lp os and Lp hyd, respectively), suberization, steady-state root pressure (P rs), sap exudation rates, sap osmotic potential, and exosmotic relaxation curves. For both rootstocks, the ‘dry’ treatment reduced fine root Lp, elicited earlier root suberization and higher sap osmotic potential, and generated greater P rs after rewatering, but the rootstocks responded differently under these conditions. Lp os, Lp hyd, and sap exudation rates were significantly higher in 110R than in 101-14Mgt, regardless of moisture treatment. Under ‘dry’ conditions, 110R maintained a similar Lp os and decreased the Lp hyd by 36% compared with ‘wet’ conditions, while both parameters were decreased by at least 50% for 101-14Mgt under ‘dry’ conditions. Interestingly, build-up of P rs in 110R was 34% lower on average than in 101-14Mgt, suggesting differences in the development of suberized apoplastic barriers between the rootstocks as visualized by analysis of suberization from fluorescence microscopy. Consistent with this pattern, 110R exhibited the greatest exosmotic Lp os (i.e. Lp os of water flowing from roots to the soil) as determined from relaxation curves under wet conditions, where backflow may have limited its capacity to generate positive xylem pressure. The traits studied here can be used in combination to provide new insights needed for

  8. Differential responses to environmental challenge by common carp Cyprinus carpio highlight the importance of coping style in integrative physiology.

    Science.gov (United States)

    Rey, S; Ribas, L; Morera Capdevila, D; Callol, A; Huntingford, F A; Pilarczyk, M; Kadri, S; MacKenzie, S

    2016-03-01

    Common carp Cyprinus carpio displaying proactive or reactive stress coping styles were acclimated to two environmental regimes (low oxygen and low temperature), and selected groups were tested for response to an inflammatory challenge (Escherichia coli lipopolysaccharide, LPS). Plasma glucose and lactate levels were measured, as were selected C. carpio-specific messenger (m)RNA transcript abundance, including cortisol receptor (CR), enolase (ENO), glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and interleukin-1-beta (IL1β) was measured in individual whole brain samples. Basal levels (in sham injected fish held in normoxic conditions at 25° C) of plasma lactate and glucose differed between coping styles, being significantly lower in proactive individuals. Both variables increased in response to LPS challenge, with the exception of plasma glucose in reactive fish held in hypoxia. Baseline levels of gene expression under control conditions were significantly different for GAPDH between behavioural phenotypes. The responses to experimental challenge were sometimes diametrically opposed between stress-coping styles in a transcript-specific manner. For CR and GAPDH, for example, the response to LPS injection in hypoxia were opposite between proactive and reactive animals. Proactive fish showed decreased CR and increased GAPDH, whereas reactive showed the opposite response. These results further highlight that screening for stress-coping styles prior to experiments in adaptive physiology can significantly affect the interpretation of data obtained. Further, this leads to a more finely tuned analytical output providing an improved understanding of variation in individual responses to both environmental and inflammatory challenge. © 2016 The Fisheries Society of the British Isles.

  9. Dopamine-Incorporated Dual Bioactive Electroactive Shape Memory Polyurethane Elastomers with Physiological Shape Recovery Temperature, High Stretchability, and Enhanced C2C12 Myogenic Differentiation.

    Science.gov (United States)

    Zhao, Xin; Dong, Ruonan; Guo, Baolin; Ma, Peter X

    2017-09-06

    Soft tissue engineering needs elastic biomaterials not only mimicking the elasticity of soft tissue but also possessing multiple bioactivity to promote cell adhesion, proliferation, and differentiation, which still remain ongoing challenges. Herein, we synthesized a series of dopamine-incorporated dual bioactive electroactive shape memory polyurethane elastomers by combining the properties of elastomeric poly(citric acid-co-polycaprolactone) (CA-PCL) polyurethane elastomer, bioactive dopamine (DA), and electroactive aniline hexamer (AH). The chemical structures, electroactivity, conductivity, thermal properties, hydrophilicity and hydration ability, mechanical properties, and degradability of the polyurethane elastomers were systematically characterized. The elastomers showed excellent shape fixity ratio and shape recovery ability under physiological conditions. The elastomers' elongation and stress were tailored by the AH content, whereas the hydrophilicity and hydration ability of the elastomers were adjusted by the content of DA and AH, as well as the doping state of AH. The viability and proliferation results of C2C12 cells seeded on the elastomers showed their excellent cytocompatibility. Additionally, by analyzing the protein and gene level, the promotion effect on myogenic differentiation of C2C12 cells by these elastomers compared to that by control groups (PCL80 000, CA-PCL elastomer, and CA-PCL elastomer with the DA segment) was demonstrated. Furthermore, the results from subcutaneous implantation confirmed the elastomers' mild host response in vivo. These results represent that these dopamine-incorporated dual bioactive electroactive shape memory polyurethane elastomers are promising candidates for soft tissue regeneration that is sensitive to electrical signals.

  10. Rice Seed Germination Underwater: Morpho-Physiological Responses and the Bases of Differential Expression of Alcoholic Fermentation Enzymes

    Directory of Open Access Journals (Sweden)

    Berta Miro

    2017-10-01

    Full Text Available The water-, energy-, and labor-intensive system of transplanted puddled rice (Oryza sativa is steadily being replaced by direct seeding due to the progressive scarcity of these resources. However, the alternate dry direct seeding leads to competition with weeds and poor establishment when soils are flooded. Direct seeded rice capable of anaerobic germination (germination in flooded soil, AG is ideal, which under rainfed ecosystems would also overcome waterlogging during germination. AG tolerance is associated with faster germination and faster elongation of coleoptiles, with the activities of alcoholic fermentation enzymes replacing aerobic respiration as a source of energy. To better understand the variability in the morpho-physiological responses and in the nature of the alcoholic fermentation enzymes during AG, 21 rice genotypes were studied. The genotypes Khao Hlan On (KHO and IR42 were used as the tolerant and susceptible checks, respectively. KHO exhibited faster germination, with 82.5% of the coleoptiles emerging out of 10 cm of water within 8 days, whereas IR42 exhibited 20% germination and limited coleoptile growth. Among the test genotypes, four performed well, including two that are drought tolerant. Increased content and activity of the alcoholic fermentation enzymes, alcohol dehydrogenase (ADH1 and acetaldehyde dehydrogenase (ALDH2a and ALDH2b, was noted in KHO under anaerobic than under aerobic conditions and also in comparison with IR42 under AG. Gene transcripts for these enzymes were also more in KHO undergoing AG. However, no major differences were observed between KHO and IR42 in the critical cis-acting regulatory elements, such as the auxin, light, and sugar response elements, in the promoters of ADH1, ALDH2a, and ALDH2b genes. Post-transcriptional and post-translational regulatory mechanisms were implicated for the increased transcript and protein content/activity of the enzymes in KHO by observing four different transcripts

  11. Witnesses in action: the effect of physical exertion on recall and recognition.

    Science.gov (United States)

    Hope, Lorraine; Lewinski, William; Dixon, Justin; Blocksidge, David; Gabbert, Fiona

    2012-04-01

    Understanding memory performance under different operational conditions is critical in many occupational settings. To examine the effect of physical exertion on memory for a witnessed event, we placed two groups of law-enforcement officers in a live, occupationally relevant scenario. One group had previously completed a high-intensity physical-assault exercise, and the other had not. Participants who completed the assault exercise showed impaired recall and recognition performance compared with the control group. Specifically, they provided significantly less accurate information concerning critical and incidental target individuals encountered during the scenario, recalled less briefing information, and provided fewer briefing updates than control participants did. Exertion was also associated with reduced accuracy in identifying the critical target from a lineup. These results support arousal-based competition accounts proposing differential allocation of resources under physiological arousal. These novel findings relating to eyewitness memory performance have important implications for victims, ordinary citizens who become witnesses, and witnesses in policing, military, and related operational contexts.

  12. 68Ga-DOTA-TOC uptake in neuroendocrine tumour and healthy tissue: differentiation of physiological uptake and pathological processes in PET/CT.

    Science.gov (United States)

    Kroiss, A; Putzer, D; Decristoforo, C; Uprimny, C; Warwitz, B; Nilica, B; Gabriel, M; Kendler, D; Waitz, D; Widmann, G; Virgolini, I J

    2013-04-01

    We wanted to establish the range of (68)Ga-DOTA-TOC uptake in liver and bone metastases of patients with neuroendocrine tumours (NET) and to establish the range of its uptake in pancreatic NET. This would allow differentiation between physiological uptake and tumour-related somatostatin receptor expression in the pancreas (including the uncinate process), liver and bone. Finally, we wanted to test for differences in patients with NET, either treated or not treated with peptide receptor radionuclide therapy (PRRT). In 249 patients, 390 (68)Ga-DOTA-TOC PET/CT studies were performed. The clinical indications for PET/CT were gastroenteropancreatic NET (194 studies), nongastroenteropancreatic NET (origin in the lung and rectum; 46 studies), NET of unknown primary (111 studies), phaeochromocytoma/glomus tumours (18 studies), and radioiodine-negative metastatic thyroid carcinoma (21 studies). SUVmax (mean ± standard deviation) values of (68)Ga-DOTA-TOC were 29.8 ± 16.5 in 162 liver metastases, 19.8 ± 18.8 in 89 bone metastases and 34.6 ± 17.1 in 43 pancreatic NET (33.6 ± 14.3 in 30 tumours of the uncinate process and 36.3 ± 21.5 in 13 tumours of the pancreatic tail). A significant difference in SUVmax (p TOC is an excellent tracer for the imaging of tumours expressing somatostatin receptors on the tumour cell surface, facilitating the detection of even small tumour lesions. The noninvasive PET/CT approach by measurement of regional SUVmax can offer important clinical information to distinguish between physiological and pathological somatostatin receptor expression, especially in the uncinate process. PRRT does not significantly influence SUVmax, except in liver metastases of patients with NET.

  13. Cardiopulmonary exercise testing in the assessment of exertional dyspnea

    Directory of Open Access Journals (Sweden)

    Debapriya Datta

    2015-01-01

    Full Text Available Dyspnea on exertion is a commonly encountered problem in clinical practice. It is usually investigated by resting tests such as pulmonary function tests and echocardiogram, which may at times can be non-diagnostic. Cardiopulmonary exercise testing (CPET measures physiologic parameters during exercise which can enable accurate identification of the cause of dyspnea. Though CPET has been around for decades and provides valuable and pertinent physiologic information on the integrated cardiopulmonary responses to exercise, it remains underutilized. The objective of this review is to provide a comprehensible overview of the underlying principles of exercise physiology, indications and contraindications of CPET, methodology and interpretative strategies involved and thereby increase the understanding of the insights that can be gained from the use of CPET.

  14. Differential impact in young and older individuals of blue-enriched white light on circadian physiology and alertness during sustained wakefulness.

    Science.gov (United States)

    Gabel, Virginie; Reichert, Carolin F; Maire, Micheline; Schmidt, Christina; Schlangen, Luc J M; Kolodyazhniy, Vitaliy; Garbazza, Corrado; Cajochen, Christian; Viola, Antoine U

    2017-08-08

    We tested the effect of different lights as a countermeasure against sleep-loss decrements in alertness, melatonin and cortisol profile, skin temperature and wrist motor activity in healthy young and older volunteers under extendend wakefulness. 26 young [mean (SE): 25.0 (0.6) y)] and 12 older participants [(mean (SE): 63.6 (1.3) y)] underwent 40-h of sustained wakefulness during 3 balanced crossover segments, once under dim light (DL: 8 lx), and once under either white light (WL: 250 lx, 2,800 K) or blue-enriched white light (BL: 250 lx, 9,000 K) exposure. Subjective sleepiness, melatonin and cortisol were assessed hourly. Skin temperature and wrist motor activity were continuously recorded. WL and BL induced an alerting response in both the older (p = 0.005) and the young participants (p = 0.021). The evening rise in melatonin was attentuated under both WL and BL only in the young. Cortisol levels were increased and activity levels decreased in the older compared to the young only under BL (p = 0.0003). Compared to the young, both proximal and distal skin temperatures were lower in older participants under all lighting conditions. Thus the color temperature of normal intensity lighting may have differential effects on circadian physiology in young and older individuals.

  15. Prenatal loud music and noise: differential impact on physiological arousal, hippocampal synaptogenesis and spatial behavior in one day-old chicks.

    Science.gov (United States)

    Sanyal, Tania; Kumar, Vivek; Nag, Tapas Chandra; Jain, Suman; Sreenivas, Vishnu; Wadhwa, Shashi

    2013-01-01

    Prenatal auditory stimulation in chicks with species-specific sound and music at 65 dB facilitates spatial orientation and learning and is associated with significant morphological and biochemical changes in the hippocampus and brainstem auditory nuclei. Increased noradrenaline level due to physiological arousal is suggested as a possible mediator for the observed beneficial effects following patterned and rhythmic sound exposure. However, studies regarding the effects of prenatal high decibel sound (110 dB; music and noise) exposure on the plasma noradrenaline level, synaptic protein expression in the hippocampus and spatial behavior of neonatal chicks remained unexplored. Here, we report that high decibel music stimulation moderately increases plasma noradrenaline level and positively modulates spatial orientation, learning and memory of one day-old chicks. In contrast, noise at the same sound pressure level results in excessive increase of plasma noradrenaline level and impairs the spatial behavior. Further, to assess the changes at the molecular level, we have quantified the expression of functional synapse markers: synaptophysin and PSD-95 in the hippocampus. Compared to the controls, both proteins show significantly increased expressions in the music stimulated group but decrease in expressions in the noise group. We propose that the differential increase of plasma noradrenaline level and altered expression of synaptic proteins in the hippocampus are responsible for the observed behavioral consequences following prenatal 110 dB music and noise stimulation.

  16. Modifications of the chemical structure of phenolics differentially affect physiological activities in pulvinar cells of Mimosa pudica L. I. Multimode effect on early membrane events.

    Science.gov (United States)

    Rocher, Françoise; Dédaldéchamp, Fabienne; Saeedi, Saed; Fleurat-Lessard, Pierrette; Chollet, Jean-Francois; Roblin, Gabriel

    2014-11-01

    A study of the structure-activity relationship carried out on several benzoic acid-related phenolics indicates that this type of compounds hinders the osmocontractile reaction of pulvinar cells in the range of 0-100%. Tentatively, we tried to find a way that could explain this differential action. With this aim, the relationship between the inhibitory effect and important molecular physico-chemical parameters (namely lipophilicity and degree of dissociation) was drawn. In addition, the effect of a variety of these compounds was investigated on their capacity to modify the electrical transmembrane potential and induce modifications in proton fluxes. Finally, using plasma membrane vesicles purified from pulvinar tissues, we examined the effects of some selected compounds on the proton pump activity and catalytic activity of the plasma membrane H(+)-ATPase. Taken together, the results indicate that a modification of the molecular structure of phenolics may induce important variation in the activity of the compound on these early membrane events. Among the tested phenolics, salicylic acid (SA) and acetylsalicylic acid (ASA, aspirin) are of particuler note, as they showed atypical effects on the physiological processes studied. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  17. Prenatal loud music and noise: differential impact on physiological arousal, hippocampal synaptogenesis and spatial behavior in one day-old chicks.

    Directory of Open Access Journals (Sweden)

    Tania Sanyal

    Full Text Available Prenatal auditory stimulation in chicks with species-specific sound and music at 65 dB facilitates spatial orientation and learning and is associated with significant morphological and biochemical changes in the hippocampus and brainstem auditory nuclei. Increased noradrenaline level due to physiological arousal is suggested as a possible mediator for the observed beneficial effects following patterned and rhythmic sound exposure. However, studies regarding the effects of prenatal high decibel sound (110 dB; music and noise exposure on the plasma noradrenaline level, synaptic protein expression in the hippocampus and spatial behavior of neonatal chicks remained unexplored. Here, we report that high decibel music stimulation moderately increases plasma noradrenaline level and positively modulates spatial orientation, learning and memory of one day-old chicks. In contrast, noise at the same sound pressure level results in excessive increase of plasma noradrenaline level and impairs the spatial behavior. Further, to assess the changes at the molecular level, we have quantified the expression of functional synapse markers: synaptophysin and PSD-95 in the hippocampus. Compared to the controls, both proteins show significantly increased expressions in the music stimulated group but decrease in expressions in the noise group. We propose that the differential increase of plasma noradrenaline level and altered expression of synaptic proteins in the hippocampus are responsible for the observed behavioral consequences following prenatal 110 dB music and noise stimulation.

  18. Prenatal Loud Music and Noise: Differential Impact on Physiological Arousal, Hippocampal Synaptogenesis and Spatial Behavior in One Day-Old Chicks

    Science.gov (United States)

    Sanyal, Tania; Kumar, Vivek; Nag, Tapas Chandra; Jain, Suman; Sreenivas, Vishnu; Wadhwa, Shashi

    2013-01-01

    Prenatal auditory stimulation in chicks with species-specific sound and music at 65 dB facilitates spatial orientation and learning and is associated with significant morphological and biochemical changes in the hippocampus and brainstem auditory nuclei. Increased noradrenaline level due to physiological arousal is suggested as a possible mediator for the observed beneficial effects following patterned and rhythmic sound exposure. However, studies regarding the effects of prenatal high decibel sound (110 dB; music and noise) exposure on the plasma noradrenaline level, synaptic protein expression in the hippocampus and spatial behavior of neonatal chicks remained unexplored. Here, we report that high decibel music stimulation moderately increases plasma noradrenaline level and positively modulates spatial orientation, learning and memory of one day-old chicks. In contrast, noise at the same sound pressure level results in excessive increase of plasma noradrenaline level and impairs the spatial behavior. Further, to assess the changes at the molecular level, we have quantified the expression of functional synapse markers: synaptophysin and PSD-95 in the hippocampus. Compared to the controls, both proteins show significantly increased expressions in the music stimulated group but decrease in expressions in the noise group. We propose that the differential increase of plasma noradrenaline level and altered expression of synaptic proteins in the hippocampus are responsible for the observed behavioral consequences following prenatal 110 dB music and noise stimulation. PMID:23861759

  19. Physiology of wrestlers` dehydration

    OpenAIRE

    Cengiz, Asim; DEMİRHAN, Bilal

    2014-01-01

    Rapid weight loss via dehydration has profound adverse effects on the wrestler's physiology and muscular endurance even with %1 of body weight loss. Additionally, there is a decline after 4% of weight loss in strength or anaerobic power performance. However, these adverse effects do not seem to impair muscle strength during high-power exertions lasting less than 30 seconds. In fact, for athletes participating in brief-duration, high- power sports, rapid weight loss may give them an advan...

  20. Differentiated Ratings of Perceived Exertion during Physical Exercise

    Science.gov (United States)

    1982-01-01

    influence of load, duration, and task. Ergonomics 20:.147- rheumatoid arthritis I. Scand. J. Rheumatol. 4:80-86, 1975. 158. 1977. 19. FRANxENHAEuSER. M...regional signals. Percept. Mot. Skills 49:683-689, 1979. 28. KINSMAN. R.A. and P.C. WEISER Subjective symptomatology during 46. ROBERTSON. R.J., R.L

  1. The use of subjective rating of exertion in Ergonomics.

    Science.gov (United States)

    Capodaglio, P

    2002-01-01

    In Ergonomics, the use of psychophysical methods for subjectively evaluating work tasks and determining acceptable loads has become more common. Daily activities at the work site are studied not only with physiological methods but also with perceptual estimation and production methods. The psychophysical methods are of special interest in field studies of short-term work tasks for which valid physiological measurements are difficult to obtain. The perceived exertion, difficulty and fatigue that a person experiences in a certain work situation is an important sign of a real or objective load. Measurement of the physical load with physiological parameters is not sufficient since it does not take into consideration the particular difficulty of the performance or the capacity of the individual. It is often difficult from technical and biomechanical analyses to understand the seriousness of a difficulty that a person experiences. Physiological determinations give important information, but they may be insufficient due to the technical problems in obtaining relevant but simple measurements for short-term activities or activities involving special movement patterns. Perceptual estimations using Borg's scales give important information because the severity of a task's difficulty depends on the individual doing the work. Observation is the most simple and used means to assess job demands. Other evaluations integrating observation are the followings: indirect estimation of energy expenditure based on prediction equations or direct measurement of oxygen consumption; measurements of forces, angles and biomechanical parameters; measurements of physiological and neurophysiological parameters during tasks. It is recommended that determinations of performances of occupational activities assess rating of perceived exertion and integrate these measurements of intensity levels with those of activity's type, duration and frequency. A better estimate of the degree of physical activity

  2. Visual control in basketball shooting under exertion conditions.

    Science.gov (United States)

    Zwierko, Teresa; Popowczak, Marek; Woźniak, Jarosław; Rokita, Andrzej

    2017-07-25

    This study examined the effect of physical exertion on gaze behavior during basketball shooting in both stationary and dynamic conditions. Thirteen skilled basketball players performed two-point shooting during a 60 second fatigue protocol. Before and after a jump shot test, players performed two free throws. Eye movements were registered using an SMI Mobile EyeTracker. The frequency of all fixation points (number) and fixation duration during the motor phases of shooting were determined using frame-by- frame analysis. The type of basketball shot differentiated gaze control: (1) fixations were longer and more frequent during free throws as compared to jump shots, (2) shooting accuracy was positively influenced by less frequent and longer fixations, (3) physical exertion resulted in significantly more frequent fixations during free throws, and (4) exertion conditions resulted in a high variation in the patterns of total fixation times during jump shots. The findings suggest that physical exertion may reduce oculomotor efficiency during aiming at a distant target. Moreover, stationary and dynamic shots require different gaze behavior strategies.

  3. Reflections on the Design of Exertion Games.

    Science.gov (United States)

    Mueller, Florian Floyd; Altimira, David; Khot, Rohit Ashot

    2015-02-01

    The design of exertion games (i.e., digital games that require physical effort from players) is a difficult intertwined challenge of combining digital games and physical effort. To aid designers in facing this challenge, we describe our experiences of designing exertion games. We outline personal reflections on our design processes and articulate analyses of players' experiences. These reflections and analyses serve to highlight the unique opportunities of combining digital games and physical effort. The insights we seek aim to enhance the understanding of exertion game design, contributing to the advancement of the field, and ultimately resulting in better games and associated player experiences.

  4. Mechanisms, measurement and management of exertional dyspnoea in asthma

    Directory of Open Access Journals (Sweden)

    Jason Weatherald

    2017-06-01

    Full Text Available Asthma is a heterogeneous condition, with dyspnoea during exercise affecting individuals to a variable degree. This narrative review explores the mechanisms and measurement of exertional dyspnoea in asthma and summarises the available evidence for the efficacy of various interventions on exertional dyspnoea. Studies on the mechanisms of dyspnoea in asthma have largely utilised direct bronchoprovocation challenges, rather than exercise, which may invoke different physiological mechanisms. Thus, the description of dyspnoea during methacholine challenge can differ from what is experienced during daily activities, including exercise. Dyspnoea perception during exercise is influenced by many interacting variables, such as asthma severity and phenotype, bronchoconstriction, dynamic hyperinflation, respiratory drive and psychological factors. In addition to the intensity of dyspnoea, the qualitative description of dyspnoea may give important clues as to the underlying mechanism and may be an important endpoint for future interventional studies. There is currently little evidence demonstrating whether pharmacological or non-pharmacological interventions specifically improve exertional dyspnoea, which is an important area for future research.

  5. Design Strategies for Balancing Exertion Games

    DEFF Research Database (Denmark)

    Jensen, Mads Møller; Grønbæk, Kaj

    2016-01-01

    , it is unclear how balancing mechanisms should be applied in exertion games, where physical and digital elements are fused. In this paper, we present an exertion game and three approaches for balancing it; a physical, an explicit-digital and an implicit-digital balancing approach. A user study that compares......In sports, if players' physical and technical abilities are mismatched, the competition is often uninteresting for them. With the emergence of exertion games, this could be changing. Player balancing, known from video games, allows players with different skill levels to compete, however...... these three approaches is used to investigate the qualities and challenges within each approach and explore how the player experience is affected by them. Based on these findings, we suggest four design strategies for balancing exertion games, so that players will stay engaged in the game and contain...

  6. Fatigue induced by physical and mental exertion increases perception of effort and impairs subsequent endurance performance

    Directory of Open Access Journals (Sweden)

    Benjamin Pageaux

    2016-11-01

    Full Text Available Endurance performance involves the prolonged maintenance of constant or self-regulated power/velocity or torque/force. While the impact of numerous determinants of endurance performance has been previously reviewed, the impact of fatigue on subsequent endurance performance still needs to be documented. This review aims to present the impact of fatigue induced by physical or mental exertion on subsequent endurance performance. For the purpose of this review, endurance performance refers to performance during whole-body or single-joint endurance exercise soliciting mainly the aerobic energy system. First, the impact of physical and mental exertion on force production capacity is presented, with specific emphasize on the fact that solely physical exertion and not mental exertion induces a decrease in force production capacity of the working muscles. Then, the negative impact of fatigue induced by physical exertion and mental exertion on subsequent endurance performance is highlighted based on experimental data. Perception of effort being identified as the variable altered by both prior physical exertion and mental exertion, future studies should investigate the underlying mechanisms increasing perception of effort overtime and in presence of fatigue during endurance exercise. Perception of effort should be considered not only as marker of exercise intensity, but also as a factor limiting endurance performance. Therefore, using a psychophysiological approach to explain the regulation of endurance performance would allow a better understanding of the interaction between physiological and psychological phenomena known to impact endurance performance.

  7. Prenatal loud music and noise: differential impact on physiological arousal, hippocampal synaptogenesis and spatial behavior in one day-old chicks

    National Research Council Canada - National Science Library

    Sanyal, Tania; Kumar, Vivek; Nag, Tapas Chandra; Jain, Suman; Sreenivas, Vishnu; Wadhwa, Shashi

    2013-01-01

    ... changes in the hippocampus and brainstem auditory nuclei. Increased noradrenaline level due to physiological arousal is suggested as a possible mediator for the observed beneficial effects following patterned and rhythmic sound exposure...

  8. Differential effects of alpha-adrenoceptor blockade on essential, physiological and isoprenaline-induced tremor: evidence for a central origin of essential tremor.

    OpenAIRE

    Abila, B; Wilson, J F; Marshall, R W; Richens, A

    1985-01-01

    Intravenous thymoxamine reduced the power of essential tremor but increased that of physiological and isoprenaline-induced tremor. These findings indicate that essential and physiological tremor have dissimilar pathophysiological mechanisms. They also suggest that central adrenergic mechanisms are involved in the pathophysiology of essential tremor and that isoprenaline-induced tremor is not a good model of essential tremor. Furthermore, alpha-adrenoceptor blockers may be a useful therapy for...

  9. The physiological determinants of drug-induced lysosomal stress resistance.

    Directory of Open Access Journals (Sweden)

    Tehetina Woldemichael

    Full Text Available Many weakly basic, lipophilic drugs accumulate in lysosomes and exert complex, pleiotropic effects on organelle structure and function. Thus, modeling how perturbations of lysosomal physiology affect the maintenance of lysosomal ion homeostasis is necessary to elucidate the key factors which determine the toxicological effects of lysosomotropic agents, in a cell-type dependent manner. Accordingly, a physiologically-based mathematical modeling and simulation approach was used to explore the dynamic, multi-parameter phenomenon of lysosomal stress. With this approach, parameters that are either directly involved in lysosomal ion transportation or lysosomal morphology were transiently altered to investigate their downstream effects on lysosomal physiology reflected by the changes they induce in lysosomal pH, chloride, and membrane potential. In addition, combinations of parameters were simultaneously altered to assess which parameter was most critical for recovery of normal lysosomal physiology. Lastly, to explore the relationship between organelle morphology and induced stress, we investigated the effects of parameters controlling organelle geometry on the restoration of normal lysosomal physiology following a transient perturbation. Collectively, our results indicate a key, interdependent role of V-ATPase number and membrane proton permeability in lysosomal stress tolerance. This suggests that the cell-type dependent regulation of V-ATPase subunit expression and turnover, together with the proton permeability properties of the lysosomal membrane, is critical to understand the differential sensitivity or resistance of different cell types to the toxic effects of lysosomotropic drugs.

  10. Exercise Physiology. Basic Stuff Series I. I.

    Science.gov (United States)

    Svoboda, Milan; And Others

    The fundamentals of exercise physiology (the study of the physiological effects of bodily exertion) form the basis for this booklet designed for teachers of physical education. The scientific principles underlying the building of muscular strength and flexibility are described and illustrated. Topics covered include: (1) muscular strength,…

  11. Perceived exertion : influence of age and cognitive development.

    Science.gov (United States)

    Groslambert, Alain; Mahon, Anthony D

    2006-01-01

    Because little is known about the effects of aging on perceived exertion, the aim of this article is to review the key findings from the published literature concerning rating of perceived exertion (RPE) in relation to the developmental level of a subject. The use of RPE in the exercise setting has included both an estimation paradigm, which is the quantification of the effort sense at a given level of exercise, and a production paradigm, which involves producing a given physiological effort based on an RPE value. The results of the review show that the cognitive developmental level of children aged 0-3 years does not allow them to rate their perceived exertion during a handgrip task. From 4 to 7 years of age, there is a critical period where children are able to progressively rate at first their peripheral sensory cues during handgrip tests, and then their cardiorespiratory cues during outdoor running in an accurate manner. Between 8 and 12 years of age, children are able to estimate and produce 2-4 cycling intensities guided by their effort sense and distinguish sensory cues from different parts of their body. However, most of the studies report that the exercise mode and the rating scale used could influence their perceptual responsiveness. During adolescence, it seems that the RPE-heart rate (HR) relationship is less pronounced than in adults. Similar to observations made in younger children, RPE values are influenced by the exercise mode, test protocol and rating scale. Limited research has examined the ability of adolescents to produce a given exercise intensity based on perceived exertion. Little else is known about RPE in this age group. In healthy middle-aged and elderly individuals, age-related differences in perceptual responsiveness may not be present as long as variations in cardiorespiratory fitness are taken into account. For this reason, RPE could be associated with HR as a useful tool for monitoring and prescribing exercise. In physically

  12. Nasal Physiology

    Science.gov (United States)

    ... Anatomy Virtual Anatomy Disclosure Statement Printer Friendly Nasal Physiology Jeremiah A. Alt, MD, PhD Noam Cohen, MD, ... control the inflammation. CONCLUSION An understanding of the physiology of the nose is critical to understand nasal ...

  13. Rice Physiology

    Science.gov (United States)

    P.A. Counce; Davidi R. Gealy; Shi-Jean Susana Sung

    2002-01-01

    Physiology occurs tn physical space through chemical reactions constrained by anatomy and morphology, yet guided by genetics. Physiology has been called the logic of life. Genes encode structural and fimcdonal proteins. These proteins are subsequently processed to produce enzymes that direct and govern the biomechanical processes involved in the physiology of the...

  14. Differential expression of microRNAs and their targets reveals a possible dual role in physiological bark disorder in rubber tree.

    Science.gov (United States)

    Lertpanyasampatha, Manassawe; Viboonjun, Unchera; Kongsawadworakul, Panida; Chrestin, Hervé; Narangajavana, Jarunya

    2014-08-15

    Trunk phloem necrosis (TPN), a physiological bark disorder of the rubber tree (Hevea brasiliensis), is a serious problem that affects the yield of natural rubber. The resultant bark dryness occurs in up to half of a plantation's trees in almost every rubber tree plantation region, causing a great annual loss of dry rubber for natural rubber production. Different types of injury and physical damage caused by mechanical activation as well as environmental stresses cause physiological bark disorder in tree. Due to the essential role of miR166, miR393 and miR167 in vascular development and abiotic stress response in diverse plant species, it was interesting to investigate the role of these miRNAs in rubber trees, particularly during development of a physiological bark disorder. In this study, the expression pattern of miR166, miR393 and miR167; and their target genes, HD-ZIP III; TIR1 and ARF8, respectively; was demonstrated in healthy tree and different TPN trees. Their existence and function in vivo was validated using RNA ligase-mediated 5' rapid amplification of cDNA ends. Taken together, the results suggest a possible dual role of these three miRNAs in maintaining normal bark regeneration in healthy trees, coping with overtapping by affecting the wound healing system leading to abnormal bark regeneration in overtapped-TPN trees, and act as additional forces that enhance the attenuation of vascular development resulting in bark necrosis and cell death in the natural-TPN tree. This is the first study to address the molecular events of miRNAs involved in the physiological bark disorder TPN in rubber tree. Further study will open the possibility to better understanding of physiological and molecular perspectives during TPN development, and lead to improvement of monitoring the exploitation of rubber tree plantations. Copyright © 2014 Elsevier GmbH. All rights reserved.

  15. Chronic Exertional Compartment Syndrome in a High School Soccer Player

    Directory of Open Access Journals (Sweden)

    James J. Bresnahan

    2015-01-01

    Full Text Available Chronic exertional compartment syndrome (CECS is a relatively rare condition that affects young adult athletes and often causes them to present to the emergency department. If left untreated, those who continue to compete at high levels may experience debilitating leg pain. Physicians may have difficulty differentiating CECS from other syndromes of the lower leg such as medial tibial stress syndrome, stress fractures, and popliteal artery entrapment. The gold standard for diagnosing CECS is intramuscular compartment pressure monitoring before and/or after 10 minutes of exercise. Some patients may choose to stop participation in sports in order to relieve their pain, which otherwise does not respond well to nonoperative treatments. In patients who wish to continue to participate in sports and live an active life, fasciotomy provides relief in 80% or more. The typical athlete can return to training in about 8 weeks. This is a case of a high school soccer player who stopped competing due to chronic exertional compartment syndrome. She had a fascial hernia, resting intramuscular pressure of 30 mmHg, and postexercise intramuscular pressure of 99 mmHg. Following fasciotomy she experienced considerable life improvement and is once again training and playing soccer without symptoms.

  16. Rowing Physiology.

    Science.gov (United States)

    Spinks, W. L.

    This review of the literature discusses and examines the methods used in physiological assessment of rowers, results of such assessments, and future directions emanating from research in the physiology of rowing. The first section discusses the energy demands of rowing, including the contribution of the energy system, anaerobic metabolism, and the…

  17. Linking genotoxic responses with cytotoxic and behavioural or physiological consequences: differential sensitivity of echinoderms (Asterias rubens) and marine molluscs (Mytilus edulis).

    Science.gov (United States)

    Canty, Martin N; Hutchinson, Thomas H; Brown, Rebecca J; Jones, Malcolm B; Jha, Awadhesh N

    2009-08-13

    Integrated laboratory studies addressed multiple biomarker responses in the sea star (Asterias rubens) and the blue mussel (Mytilus edulis) exposed to a range of concentrations of direct and indirect acting genotoxins: methyl methane sulfonate (MMS) and cyclophosphamide (CP; an environmentally relevant anti-cancer pharmaceutical), respectively, in order to determine if the expressed genotoxicity has knock-on effects at the higher levels of biological organisation. The experimental design aimed to concurrently evaluate biomarkers of behavioural and physiological conditions (i.e. 'righting time' and 'clearance rate' for sea stars and mussels, respectively) in addition to cytotoxicity (neutral red retention assay), induction of micronuclei (Mn) and DNA strand breaks (as determined by the Comet assay). The protocol also included the determination of the maximum tolerated concentration (MTC), prior to genotoxic evaluation. The 3d MTC, as determined by the survival of the organisms, showed sea stars to be more sensitive than mussels to MMS (18 and 32 mg L(-1), respectively) and CP (56 and 180 mg L(-1), respectively). For both species and chemicals, cytotoxicity was not found to be significantly different compared to controls. Apart from the MMS exposure to sea stars (which showed 100% mortality at higher concentrations after 5d exposure), clear dose-response relationships were observed for both genotoxicity endpoints in each species. Following exposure to CP, good correlations were also found between the behavioural and physiological responses and genetic damage in each species (sea stars-MN vs. RT: R=0.73; Comet vs. RT: R=0.91; mussels-MN vs. CR: R=0.69; Comet vs. CR: R=0.72). This integrated approach, applying non-invasive assays to simultaneously determine the responses at different levels of biological organisation, indicates the potential value of behavioural and physiological measures in determining the toxicity of chemicals to marine organisms and highlights also

  18. Traction Forces exerted by crawling cells

    Science.gov (United States)

    Alonso-Latorre, Baldomero; Del Alamo, Juan C.; Rodriguez-Rodriguez, Javier; Aliseda, Alberto; Meili, Rudolph; Firtel, Richard; Lasheras, Juan C.

    2006-11-01

    We measure the forces exerted by Dictyostelium discoideum cells crawling over a deformable substrate from the displacements of fluorescent beads embedded in it. A particle tracking technique similar to PIV is used to obtain the displacements. From them, forces are computed by solving the elasto-static equation in a finite thickness slab. We will show that the finite thickness of the substrate and the distance of the beads to its surface affect substantially the results, although previous traction cytometry techniques neglected them. The measured forces are correlated to the different stages of the crawling cycle for various cell strains. It has been observed that a large fraction of the forces measured on the substrate are originated by the cell's internal tension through all the stages of motion, including the protrusion of pseudopods. This result suggests that the viscous drag exerted by the fluid in which the cells are immersed is very small compared to the forces applied by the cytoskeleton on the substrate.

  19. Recommendations for aerobic endurance training based on subjective ratings of perceived exertion in healthy seniors.

    Science.gov (United States)

    Donath, Lars; Zahner, Lukas; Cordes, Mareike; Hanssen, Henner; Schmidt-Trucksäss, Aarno; Faude, Oliver

    2013-01-01

    The study investigated physiological responses during 2-km walking at a certain intensity of a previously performed maximal exercise test where moderate perceived exertion was reported. Twenty seniors were examined by an incremental walking treadmill test to obtain maximal oxygen uptake (VO2max). A submaximal 2-km walking test was applied 1 wk later. The corresponding moderate perceived exertion (4 on the CR-10 scale) during the VO2max test was applied to the 2-km treadmill test. Moderate exertion (mean rating of perceived exertion [RPE]: 4 ± 1) led to 76% ± 8% of VO2max and 79% ± 6% of maximal heart rate. RPE values drifted with a significant time effect (p = .001, η(p) = .58) during the 2-km test from 3 ± 0.7 to 4.6 ± 0.8. Total energy expenditure (EE) was 3.3 ± 0.5 kcal/kg. No gender differences in ventilatory, heart-rate, or EE data occurred. Brisk walking at moderate RPE of 3-5 would lead to a beneficial physiological response during endurance training and a weekly EE of nearly 1,200 kcal when exercising 5 times/wk for 30 min.

  20. Genetic Influences on Physiological and Subjective Responses to an Aerobic Exercise Session among Sedentary Adults

    Directory of Open Access Journals (Sweden)

    Hollis C. Karoly

    2012-01-01

    Full Text Available Objective. To determine whether genetic variants suggested by the literature to be associated with physiology and fitness phenotypes predicted differential physiological and subjective responses to a bout of aerobic exercise among inactive but otherwise healthy adults. Method. Participants completed a 30-minute submaximal aerobic exercise session. Measures of physiological and subjective responding were taken before, during, and after exercise. 14 single nucleotide polymorphisms (SNPs that have been previously associated with various exercise phenotypes were tested for associations with physiological and subjective response to exercise phenotypes. Results. We found that two SNPs in the FTO gene (rs8044769 and rs3751812 were related to positive affect change during exercise. Two SNPs in the CREB1 gene (rs2253206 and 2360969 were related to change in temperature during exercise and with maximal oxygen capacity (VO2 max. The SLIT2 SNP rs1379659 and the FAM5C SNP rs1935881 were associated with norepinephrine change during exercise. Finally, the OPRM1 SNP rs1799971 was related to changes in norepinephrine, lactate, and rate of perceived exertion (RPE during exercise. Conclusion. Genetic factors influence both physiological and subjective responses to exercise. A better understanding of genetic factors underlying physiological and subjective responses to aerobic exercise has implications for development and potential tailoring of exercise interventions.

  1. Using heart rate variability for automated identification of exercise exertion levels.

    Science.gov (United States)

    Finkelstein, Joseph; Jeong, In Cheol

    2015-01-01

    Heart rate monitoring is being used to estimate activity of autonomous nervous system by analysing heart rate variability (HRV). HRV has been recently shown to be effective means to monitor efficacy of exercise in patients with cardiovascular conditions and older adults. Whether HRV can be used to identify exercise exertion levels is unknown. There are multiple approaches to analyse HRV however it is not clear which approach is optimal in assessing cycling exercise. Previous studies demonstrated potential of analysis of short-term sequences of beat-by-beat heart rate data in a time domain for continuous monitoring of levels of physiological stress. The goal of this study was to assess the potential value of short-term HRV analysis during cycling exercise for automated identification of exercise exertion level. HRV indices were compared during rest, height of exercise exertion, and exercise recovery. Comparative analysis of HRV during cycling exercise demonstrated responsiveness of time-domain indices to different phases of an exercise program. Using discriminant analysis, canonical discriminant functions were built which correctly identified 100% of 'highest level of exertion' and 80.0% of 'rest' episodes. HRV demonstrated high potential in monitoring autonomic balance and exercise exertion during cycling exercise program.

  2. Does heavy physical exertion trigger myocardial infarction?

    DEFF Research Database (Denmark)

    Hallqvist, J; Möller, J; Ahlbom, A

    2000-01-01

    To study possible triggering of first events of acute myocardial infarction by heavy physical exertion, the authors conducted a case-crossover analysis (1993-1994) within a population-based case-referent study in Stockholm County, Sweden (the Stockholm Heart Epidemiology Program). Interviews were...... million person-hours, and the attributable proportion was 5.7 percent. The risk was modified by physical fitness, with an increased risk being seen among sedentary subjects as in earlier studies, but the data also suggested a U-shaped association. In addition, the trigger effect was modified......, and a standard case-referent analysis) were applied to overcome the threat of misclassification of control exposure information. A case-crossover analysis in a random sample of healthy subjects resulted in a relative risk close to unity, as expected....

  3. Mechanisms of exertional fatigue in muscle glycogenoses

    DEFF Research Database (Denmark)

    Vissing, John; Haller, Ronald G

    2012-01-01

    Exertional fatigue early in exercise is a clinical hallmark of muscle glycogenoses, which is often coupled with painful muscle contractures and episodes of myoglobinuria. A fundamental biochemical problem in these conditions is the impaired generation of ATP to fuel muscle contractions, which...... relates directly to the metabolic defect, but also to substrate-limited energy deficiency, as exemplified by the "second wind" phenomenon in McArdle disease. A number of secondary events may also play a role in inducing premature fatigue in glycogenoses, including (1) absent or blunted muscle acidosis...... and aerobic energy for muscle contraction; and the pathological fatigue that occurs when glycogenolysis and/or glycolysis is blocked imply an important role for theses metabolic pathways in normal muscle fatigue....

  4. Pituitary adenylate cyclase activating polypeptide (PACAP signalling exerts chondrogenesis promoting and protecting effects: implication of calcineurin as a downstream target.

    Directory of Open Access Journals (Sweden)

    Tamás Juhász

    Full Text Available Pituitary adenylate cyclase activating polypeptide (PACAP is an important neurotrophic factor influencing differentiation of neuronal elements and exerting protecting role during traumatic injuries or inflammatory processes of the central nervous system. Although increasing evidence is available on its presence and protecting function in various peripheral tissues, little is known about the role of PACAP in formation of skeletal components. To this end, we aimed to map elements of PACAP signalling in developing cartilage under physiological conditions and during oxidative stress. mRNAs of PACAP and its receptors (PAC1,VPAC1, VPAC2 were detectable during differentiation of chicken limb bud-derived chondrogenic cells in micromass cell cultures. Expression of PAC1 protein showed a peak on days of final commitment of chondrogenic cells. Administration of either the PAC1 receptor agonist PACAP 1-38, or PACAP 6-38 that is generally used as a PAC1 antagonist, augmented cartilage formation, stimulated cell proliferation and enhanced PAC1 and Sox9 protein expression. Both variants of PACAP elevated the protein expression and activity of the Ca-calmodulin dependent Ser/Thr protein phosphatase calcineurin. Application of PACAPs failed to rescue cartilage formation when the activity of calcineurin was pharmacologically inhibited with cyclosporine A. Moreover, exogenous PACAPs prevented diminishing of cartilage formation and decrease of calcineurin activity during oxidative stress. As an unexpected phenomenon, PACAP 6-38 elicited similar effects to those of PACAP 1-38, although to a different extent. On the basis of the above results, we propose calcineurin as a downstream target of PACAP signalling in differentiating chondrocytes either in normal or pathophysiological conditions. Our observations imply the therapeutical perspective that PACAP can be applied as a natural agent that may have protecting effect during joint inflammation and/or may promote

  5. Understanding the Mismatch Between Coaches' and Players' Perceptions of Exertion

    NARCIS (Netherlands)

    Brink, Michel S.; Kersten, Anna W.; Frencken, Wouter G. P.

    A mismatch between the training exertion intended by a coach and the exertion perceived by players is well established in sports. However, it is unknown whether coaches can accurately observe exertion of individual players during training. Furthermore, the discrepancy in coaches' and players'

  6. Regulatory Physiology

    Science.gov (United States)

    Lane, Helen W.; Whitson, Peggy A.; Putcha, Lakshmi; Baker, Ellen; Smith, Scott M.; Stewart, Karen; Gretebeck, Randall; Nimmagudda, R. R.; Schoeller, Dale A.; Davis-Street, Janis

    1999-01-01

    As noted elsewhere in this report, a central goal of the Extended Duration Orbiter Medical Project (EDOMP) was to ensure that cardiovascular and muscle function were adequate to perform an emergency egress after 16 days of spaceflight. The goals of the Regulatory Physiology component of the EDOMP were to identify and subsequently ameliorate those biochemical and nutritional factors that deplete physiological reserves or increase risk for disease, and to facilitate the development of effective muscle, exercise, and cardiovascular countermeasures. The component investigations designed to meet these goals focused on biochemical and physiological aspects of nutrition and metabolism, the risk of renal (kidney) stone formation, gastrointestinal function, and sleep in space. Investigations involved both ground-based protocols to validate proposed methods and flight studies to test those methods. Two hardware tests were also completed.

  7. Measures of acute physiology, comorbidity and functional status to differentiate illness severity and length of stay among acute general medical admissions: a prospective cohort study.

    Science.gov (United States)

    Huggan, P J; Akram, F; Er, B H D; Christen, L S J; Weixian, L; Lim, V; Huang, Y; Merchant, R A

    2015-07-01

    Simple measures of acute physiologic compromise, functional status and comorbidity may help clinicians to make decisions relating to clinical care and resource utilisation. To explore the usefulness of common assessment tools in predicting outcomes of (i) death or intensive care unit (ICU) admission and (ii) length of hospital stay at a busy tertiary hospital in Singapore. Three hundred and ninety-eight consecutive admissions to two general medicine teams were prospectively assessed during 2 months in 2011. Patients were followed until discharge or transfer to ICU/high dependency unit (HDU). Data collected included routine demographic data, final diagnosis, comorbid conditions including a weighted prognostic comorbidity index (the updated Charlson index) and the modified Early Warning Score (MEWS) at presentation to the emergency department. The admission modified Barthel Index was recorded for patients aged 65 and over. Death and total length of hospital stay were recorded in all cases. Of 398 patients, 16 (4 %) died or were transferred to ICU and 99 (25%) stayed for more than 7 days. Medical early warning (MEW) scores of ≥5 were significantly associated with death or ICU admission (hazard ratio 5.50, 95% confidence interval 1.77-17.07, P = 0.003). There was no independent association between this outcome and the Charlson score or admission Barthel Index. Excess length of stay was associated with a modified Barthel Index ≤17 and altered mental status at presentation. Among unselected general medical patients, MEW scores of ≥5 were significantly associated with death or ICU admissions and only functional status and altered mental status were independent predictors of excess length of stay. © 2015 Royal Australasian College of Physicians.

  8. Physiological performance and differential expression profiling of genes associated with drought tolerance in root tissue of four contrasting varieties of two Gossypium species.

    Science.gov (United States)

    Singh, Ruchi; Pandey, Neha; Kumar, Anil; Shirke, Pramod A

    2016-01-01

    Root growth in drying soil is generally limited by a combination of mechanical impedance and water stress. As the major function of root tissue is water and nutrient uptake, so it imparts an important role in plant growth and stress management. Previously, we have studied physiological performance and expression profiling of gene associated with drought tolerance in leaf tissue of four cotton varieties. Here, we have further continued our studies with the root tissue of these varieties. The Gossypium hirsutum species JKC-770 is drought-tolerant and KC-2 is drought-sensitive, while Gossypium herbaceum species JKC-717 is drought-tolerant and RAHS-187 is drought-sensitive. JKC-770 and JKC-717 the drought-tolerant varieties showed a comparatively high glutathione-S-transferase, superoxide dismutase, proline along with their gene expression, and low malondialdehyde content indicating low membrane damage and better antioxidative defense under drought condition. The expression levels of cellulose synthase, xyloglucan:xyloglucosyl transferase, and glycosyl hydrolases suggest modulation in cell wall structure and partitioning of sugars towards osmoprotectants instead of cell wall biosynthesis in tolerant varieties. Heat shock proteins and serine/threonine protein phosphotases show upregulation under drought condition, which are responsible for temperature tolerance and protein phosphorylation, respectively. These effects many metabolic processes and may be playing a key role in drought tolerance and adaptability of JKC-770 towards drought tolerance. The long-term water use efficiency (WUE) estimated in terms of carbon isotope discrimination (∆(13)C) in the root tissues showed maximum depletion in the ∆(13)C values in JKC-770 variety, while minimum in RAHS-187 under drought stress with reference to their respective control, suggesting a high WUE in JKC-770 variety.

  9. Differential effect of whole-ear shading after heading on the physiology, biochemistry and yield index of stay-green and non-stay-green wheat genotypes.

    Science.gov (United States)

    Li, Qing; Zhong, Shengfu; Sun, Sifan; Fatima, Syeda Akash; Zhang, Min; Chen, Wanquan; Huang, Qianglan; Tang, Shengwen; Luo, Peigao

    2017-01-01

    Two winter wheat cultivars (the functional stay-green CN12 and non-stay-green CN19) were used to investigate the effects of ear-shading on grain yield and to elucidate the differential mechanisms of different cultivars. The photosynthetic parameters, chlorophyll fluorescence, antioxidant enzyme activities, and chlorophyll contents were measured 0, 15 and 30 days after heading (DAH) under both shaded and non-shaded conditions. The final grain-yield index was also measured. Shading had a smaller effect on the net photosynthetic rate (Pn), intercellular CO2 concentration (Ci), stomatal conductance (Gs), maximal photochemical efficiency of PSII (Fv/Fm) and coefficient of non-photochemical fluorescence quenching (qN) but a greater effect on both superoxide dismutase (SOD) and catalase (CAT) activities in CN12 than it did in CN19. Shading slightly altered the timeframe of leaf senescence in CN12 and may have accelerated leaf senescence in CN19. Moreover, shading had only a small effect on the weight of grains per spike (WGS) in CN12 compared with CN19, mainly resulting from the number of grains per spike (NGS) rather than the 1000-grain weight (SGW). In conclusion, the flag leaves of functional stay-green wheat could serve as potential "buffers" and/or "compensators" for ear photosynthesis, which is actively regulated by the antioxidant enzyme system and prevents yield loss. Thus, a functional stay-green genotype could be more tolerant to environmental stress than a non-stay-green genotype.

  10. Differential effects of common variants in SCN2A on general cognitive ability, brain physiology, and messenger RNA expression in schizophrenia cases and control individuals.

    Science.gov (United States)

    Dickinson, Dwight; Straub, Richard E; Trampush, Joey W; Gao, Yuan; Feng, Ningping; Xie, Bin; Shin, Joo Heon; Lim, Hun Ki; Ursini, Gianluca; Bigos, Kristin L; Kolachana, Bhaskar; Hashimoto, Ryota; Takeda, Masatoshi; Baum, Graham L; Rujescu, Dan; Callicott, Joseph H; Hyde, Thomas M; Berman, Karen F; Kleinman, Joel E; Weinberger, Daniel R

    2014-06-01

    One approach to understanding the genetic complexity of schizophrenia is to study associated behavioral and biological phenotypes that may be more directly linked to genetic variation. To identify single-nucleotide polymorphisms associated with general cognitive ability (g) in people with schizophrenia and control individuals. Genomewide association study, followed by analyses in unaffected siblings and independent schizophrenia samples, functional magnetic resonance imaging studies of brain physiology in vivo, and RNA sequencing in postmortem brain samples. The discovery cohort and unaffected siblings were participants in the National Institute of Mental Health Clinical Brain Disorders Branch schizophrenia genetics studies. Additional schizophrenia cohorts were from psychiatric treatment settings in the United States, Japan, and Germany. The discovery cohort comprised 339 with schizophrenia and 363 community control participants. Follow-up analyses studied 147 unaffected siblings of the schizophrenia cases and independent schizophrenia samples including a total of an additional 668 participants. Imaging analyses included 87 schizophrenia cases and 397 control individuals. Brain tissue samples were available for 64 cases and 61 control individuals. We studied genomewide association with g, by group, in the discovery cohort. We used selected genotypes to test specific associations in unaffected siblings and independent schizophrenia samples. Imaging analyses focused on activation in the prefrontal cortex during working memory. Brain tissue studies yielded messenger RNA expression levels for RefSeq transcripts. The schizophrenia discovery cohort showed genomewide-significant association of g with polymorphisms in sodium channel gene SCN2A, accounting for 10.4% of g variance (rs10174400, P = 9.27 × 10(-10)). Control individuals showed a trend for g/genotype association with reversed allelic directionality. The genotype-by-group interaction was also genomewide

  11. Physiological correlates of ecological divergence along an urbanization gradient: differential tolerance to ammonia among molecular forms of the malaria mosquito Anopheles gambiae.

    Science.gov (United States)

    Tene Fossog, Billy; Antonio-Nkondjio, Christophe; Kengne, Pierre; Njiokou, Flobert; Besansky, Nora J; Costantini, Carlo

    2013-01-07

    form. In agreement with expectations based on the pattern of habitat partitioning and exposure to ammonia in larval habitats in Yaounde, the M form showed greater tolerance to ammonia compared to the S form. This trait may be part of the physiological machinery allowing forest populations of the M form to colonize polluted larval habitats, which is at the heart of its niche expansion in densely populated human settlements in Cameroon.

  12. Physiological correlates of ecological divergence along an urbanization gradient: differential tolerance to ammonia among molecular forms of the malaria mosquito Anopheles gambiae

    Directory of Open Access Journals (Sweden)

    Tene Fossog Billy

    2013-01-01

    a greater mean and variance compared to the S form. Conclusions In agreement with expectations based on the pattern of habitat partitioning and exposure to ammonia in larval habitats in Yaounde, the M form showed greater tolerance to ammonia compared to the S form. This trait may be part of the physiological machinery allowing forest populations of the M form to colonize polluted larval habitats, which is at the heart of its niche expansion in densely populated human settlements in Cameroon.

  13. Effects of acclimation on water and electrolitic disbalance in soldiers during exertional heat stress

    Directory of Open Access Journals (Sweden)

    Radaković Sonja S.

    2007-01-01

    Full Text Available Background/Aim. Exertional heat stress is a common problem in military services. The aim of this study was to examine changes in body water and serum concentrations of some electrolites in soldiers during exertional heat stress (EHST, as well as effects of 10-day passive or active acclimation in a climatic chamber. Methods. Forty male soldiers with high aerobic capacity, performed EHST either in cool (20 ºC, 16 ºC WBGT-wet bulb globe temperature, or hot (40 ºC, 25 ºC WBGT environment, unacclimatized, or after 10 days of passive or active acclimation. The subjects were allowed to drink tap water ad libitum during EHST. Mean skin (Tsk and tympanic (Tty temperatures and heart rates (HR measured physiological strain, while sweat rate (SwR, and serum concentrations of sodium, potassium and osmolality measured changes in water and electrolyte status. Blood samples were collected before and immediately after the EHST. Results. Exertional heat stress in hot conditions induced physiological heat stress (increase in Tty, HR, and SwR, with significant decrease in serum sodium concentration (140.6±1.52 before vs 138.5±1.0 mmol/l after EHST, p < 0.01 and osmolality (280.7±3.8 vs 277.5±2.6 mOsm/kg, p < 0.05 in the unacclimatized group. The acclimated soldiers suffered no such effects of exertional heat stress, despite almost the same degree of heat strain, measured by Tty, HR and SwR. Conclusion. In the trained soldiers, 10-day passive or active acclimation in a climatic chamber can prevent disturbances in water and electrolytic balance, i.e. decrease in serum sodium concentrations and osmolality induced by exertional heat stress.

  14. Reproductive physiology

    Science.gov (United States)

    Gee, G.F.; Russman, S.E.; Ellis, David H.; Gee, George F.; Mirande, Claire M.

    1996-01-01

    Conclusions: Although the general pattern of avian physiology applies to cranes, we have identified many physiological mechanisms (e.g., effects of disturbance) that need further study. Studies with cranes are expensive compared to those done with domestic fowl because of the crane's larger size, low reproductive rate, and delayed sexual maturity. To summarize, the crane reproductive system is composed of physiological and anatomical elements whose function is controlled by an integrated neural-endocrine system. Males generally produce semen at a younger age than when females lay eggs. Eggs are laid in clutches of two (1 to 3), and females will lay additional clutches if the preceding clutches are removed. Both sexes build nests and incubate the eggs. Molt begins during incubation and body molt may be completed annually in breeding pairs. However, remiges are replaced sequentially over 2 to 3 years, or abruptly every 2 to 3 years in other species. Most immature birds replace their juvenal remiges over a 2 to 3 year period. Stress interferes with reproduction in cranes by reducing egg production or terminating the reproductive effort. In other birds, stress elevates corticosterone levels and decreases LHRH release. We know little about the physiological response of cranes to stress.

  15. Exercise physiology

    DEFF Research Database (Denmark)

    Kiens, Bente; Richter, Erik; Wojtaszewski, Jørgen

    2014-01-01

    The passing of Professor Bengt Saltin on September 12, 2014 truly marks the end of an era. As editor of the Journal of Applied Physiology and one of Bengt’s many collaborators and colleagues, I wanted the Journal to celebrate his many seminal contributions by means of an Editorial. Professor Bente...

  16. Differential effect of whole-ear shading after heading on the physiology, biochemistry and yield index of stay-green and non-stay-green wheat genotypes.

    Directory of Open Access Journals (Sweden)

    Qing Li

    Full Text Available Two winter wheat cultivars (the functional stay-green CN12 and non-stay-green CN19 were used to investigate the effects of ear-shading on grain yield and to elucidate the differential mechanisms of different cultivars. The photosynthetic parameters, chlorophyll fluorescence, antioxidant enzyme activities, and chlorophyll contents were measured 0, 15 and 30 days after heading (DAH under both shaded and non-shaded conditions. The final grain-yield index was also measured. Shading had a smaller effect on the net photosynthetic rate (Pn, intercellular CO2 concentration (Ci, stomatal conductance (Gs, maximal photochemical efficiency of PSII (Fv/Fm and coefficient of non-photochemical fluorescence quenching (qN but a greater effect on both superoxide dismutase (SOD and catalase (CAT activities in CN12 than it did in CN19. Shading slightly altered the timeframe of leaf senescence in CN12 and may have accelerated leaf senescence in CN19. Moreover, shading had only a small effect on the weight of grains per spike (WGS in CN12 compared with CN19, mainly resulting from the number of grains per spike (NGS rather than the 1000-grain weight (SGW. In conclusion, the flag leaves of functional stay-green wheat could serve as potential "buffers" and/or "compensators" for ear photosynthesis, which is actively regulated by the antioxidant enzyme system and prevents yield loss. Thus, a functional stay-green genotype could be more tolerant to environmental stress than a non-stay-green genotype.

  17. Exertional dyspnoea in COPD: the clinical utility of cardiopulmonary exercise testing

    Directory of Open Access Journals (Sweden)

    Denis E. O'Donnell

    2016-09-01

    Full Text Available Activity-related dyspnoea is often the most distressing symptom experienced by patients with chronic obstructive pulmonary disease (COPD and can persist despite comprehensive medical management. It is now clear that dyspnoea during physical activity occurs across the spectrum of disease severity, even in those with mild airway obstruction. Our understanding of the nature and source of dyspnoea is incomplete, but current aetiological concepts emphasise the importance of increased central neural drive to breathe in the setting of a reduced ability of the respiratory system to appropriately respond. Since dyspnoea is provoked or aggravated by physical activity, its concurrent measurement during standardised laboratory exercise testing is clearly important. Combining measurement of perceptual and physiological responses during exercise can provide valuable insights into symptom severity and its pathophysiological underpinnings. This review summarises the abnormal physiological responses to exercise in COPD, as these form the basis for modern constructs of the neurobiology of exertional dyspnoea. The main objectives are: 1 to examine the role of cardiopulmonary exercise testing (CPET in uncovering the physiological mechanisms of exertional dyspnoea in patients with mild-to-moderate COPD; 2 to examine the escalating negative sensory consequences of progressive respiratory impairment with disease advancement; and 3 to build a physiological rationale for individualised treatment optimisation based on CPET.

  18. Cytotoxic effects exerted by Tritrichomonas foetus pseudocysts.

    Science.gov (United States)

    Pereira-Neves, Antonio; Nascimento, Ligia Ferreira; Benchimol, Marlene

    2012-07-01

    The protozoan parasite Tritrichomonas foetus displays a pear-shaped form and a pseudocyst stage. However, little is known about the biology of the pseudocyst. The aim of this work was to assess whether pseudocysts exert cytotoxic effects during their interaction with MDCK cells (an epithelial kidney canine cell line) and compare their behavior to that of the pear-shaped parasites. Pseudocysts and pear-shaped parasites from both cultured and freshly isolated T. foetus were used. Electron microscopy revealed that the epithelial cells exhibited more signs of injury, such as depletion of microvilli, retraction from neighboring cells and swollen mitochondria with loss of electron density in the matrix, when the pseudocysts were used in interaction experiments. In addition, during the co-incubation with MDCK cells, pseudocysts exhibited a more intense amoeboid transformation than that found in pear-shaped parasites. The MTT viability assay demonstrated that the pseudocysts were more cytotoxic when in contact with host cells as compared to the flagellated pear-shaped parasites. The JC-1 viability assay revealed that pseudocysts induced a higher loss of mitochondrial membrane potential compared to pear-shaped parasites. Pseudocysts undergoing a budding process were observed after 2.5h of co-incubation with MDCK cells. Our results suggest that the T. foetus pseudocyst might be a more aggressive form. Copyright © 2011 Elsevier GmbH. All rights reserved.

  19. Exertional Tolerance Assessments after Mild Traumatic Brain Injury: A Systematic Review.

    Science.gov (United States)

    Quatman-Yates, Catherine; Bailes, Anna; Constand, Sara; Sroka, Mary Claire; Nissen, Katharine; Kurowski, Brad; Hugentobler, Jason

    2017-12-22

    The objective of this study was to review the literature to identify and summarize strategies for evaluating responses to physical exertion after mild traumatic brain injury (mTBI) for clinical and research purposes. PubMed and EBSCOHost through December 31, 2016. Two independent reviewers selected studies based on the following criteria: 1) inclusion of participants with mTBI/concussion, 2) use of a measurement of physiological or psychosomatic response to exertion, 3) a repeatable description of the exertion protocol was provided, 4) a sample of at least 10 participants with a mean age between 8-65 years, and 5) the article was in English. The search process yielded 2,685 articles, of which 14 studies met the eligibility requirements. A quality assessment using a checklist was conducted for each study by two independent study team members and verified by a third team member. Data were extracted by a one team member and verified by a second team member. A qualitative synthesis of the studies revealed that most protocols employed a treadmill or cycle ergometer as the exercise modality. Protocol methods varied across studies including differences in initial intensity determination, progression parameters, and exertion duration. Common outcome measures were self-reported symptoms, heart rate, and blood pressure. The strongest evidence indicates that exertional assessments can provide important insight about mTBI recovery and should be administered using symptoms as a guide. Additional studies are needed to verify an optimal modes and protocols for post-mTBI exertional assessments. Copyright © 2017. Published by Elsevier Inc.

  20. Two-dimensional strain analysis of the global and regional myocardial function for the differentiation of pathologic and physiologic left ventricular hypertrophy: a study in athletes and in patients with hypertrophic cardiomyopathy.

    Science.gov (United States)

    Butz, T; van Buuren, F; Mellwig, K P; Langer, C; Plehn, G; Meissner, A; Trappe, H J; Horstkotte, D; Faber, L

    2011-01-01

    Two-dimensional strain (2DS) is a novel method to measure strain from standard two-dimensional echocardiographic images by speckle tracking, which is less angle dependent and more reproducible than conventional Doppler-derived strain. The objective of our study was to characterize global and regional function abnormalities using 2DS and strain rate analysis in patients (pts) with pathological left ventricular hypertrophy (LVH) caused by non-obstructive hypertrophic cardiomyopathy (HCM), in top level athletes, and in healthy controls. The hypothetical question was, if 2DS might be useful as additional tool in differentiating between pathologic and physiologic hypertrophy in top-level athletes. We consecutively studied 53 subjects, 15 pts with hypertrophic cardiomyopathy (HCM), 20 competitive top-level athletes, and a control group of 18 sedentary normal subjects by standard echocardiography according to ASE guidelines. Global longitudinal strain (GLS) and regional peak systolic strain (PSS) was assessed by 2DS in the apical four-chamber-view using a dedicated software. All components of strain were significantly reduced in pts with HCM (GLS: -8.1 ± 3.8%; P < 0.001) when compared with athletes (-15.2 ± 3.6%) and control subjects (-16.0 ± 2.8%). In general, there was no significant difference between the strain values of the athletes and the control group, but in some of the segments, the strain values of the control group were significantly higher than those in the athletes. A cut-off value of GLS less than -10% for the diagnosis of pathologic hypertrophy (HCM) resulted in a sensitivity of 80.0% and a specificity of 95.0%. The combination of TDI (averaged S', E') and 2DS (GLS) cut-off values for the detection of pathologic LVH in HCM demonstrated a sensitivity of 100%, and a specificity of 95%. Two-dimensional strain is a new simple and rapid method to measure GLS and PSS as components of systolic strain. This technique could offer a unique approach to quantify

  1. Garlic exerts allelopathic effects on pepper physiology in a hydroponic co-culture system

    Directory of Open Access Journals (Sweden)

    Haiyan Ding

    2016-05-01

    Full Text Available A hydroponic co-culture system was adopted to determine the allelopathic potential of garlic on the growth of pepper plants. Different numbers of garlic plants (0, 2, 4, 8 and 12 were hydroponically co-cultured with two pepper plants to investigate allelopathic effects on the growth attributes and antioxidative defense system of the test pepper plants. The responses of the pepper plants depended on the number of garlic plants included in the co-culture system, indicating an association of pepper growth with the garlic root exudate concentration. When grown at a pepper/garlic ratio of 1:1 or 1:2, the pepper plant height, chlorophyll content, and peroxidase (POD, catalase (CAT and phenylalanine ammonia-lyase (PAL activities were significantly increased after 30 days of co-culture; in contrast, reduction in methane dicarboxylic aldehyde (MDA content was observed. However, when the pepper/garlic ratio was 1:4 or higher, these morphological indices and protective enzyme activities were significantly inhibited, whereas MDA levels in the pepper leaves were significantly increased due to severe membrane lipid peroxidation. The results indicate that although low concentrations of garlic root exudates appear to induce protective enzyme systems and promote pepper growth, high concentrations have deleterious effects. These findings suggest that further investigations should optimize the co-culture pepper/garlic ratio to reduce continuous cropping obstacles in pepper production.

  2. Occupational physiology

    CERN Document Server

    Toomingas, Allan; Tornqvist, Ewa Wigaeus

    2011-01-01

    In a clear and accessible presentation, Occupational Physiology focuses on important issues in the modern working world. Exploring major public health problems-such as musculoskeletal disorders and stress-this book explains connections between work, well-being, and health based on up-to-date research in the field. It provides useful methods for risk assessment and guidelines on arranging a good working life from the perspective of the working individual, the company, and society as a whole.The book focuses on common, stressful situations in different professions. Reviewing bodily demands and r

  3. Force Exertion Capacity Measurements in Haptic Virtual Environments

    Science.gov (United States)

    Munih, Marko; Bardorfer, Ales; Ceru, Bojan; Bajd, Tadej; Zupan, Anton

    2010-01-01

    An objective test for evaluating functional status of the upper limbs (ULs) in patients with muscular distrophy (MD) is presented. The method allows for quantitative assessment of the UL functional state with an emphasis on force exertion capacity. The experimental measurement setup and the methodology for the assessment of maximal exertable force…

  4. The effects of acclimatization on blood clotting parameters in exertional heat stress

    Directory of Open Access Journals (Sweden)

    Vesić Zoran

    2013-01-01

    Full Text Available Background/Aim. Exertional heat stress is a common problem in military services. Considering the coagulation abnormalities are of major importance in development of severe heat stroke, we wanted to examine changes in hemostatic parameters in soldiers during exertional heat stress test as well as the effects of a 10-day passive or active acclimatization in a climatic chamber. Methods. A total of 40 male soldiers with high aerobic capacity performed exertional heat stress test (EHST either in cool [20ºC, 16ºC wet bulb globe temperature (WBGT], or hot (40ºC, 29ºC, (WBGT environment, unacclimatized (U or after 10 days of passive (P or active (A acclimatization. Physiological strain was measured by tympanic temperatures (Tty and heart rates (HR. Platelet count (PC, antithrombin III (AT, and prothrombin time (PT were assessed in blood samples collected before and immediately after the EHST. Results. EHST in hot conditions induced physiological heat stress (increase in Tty and HR, with a significant increase in prothrombin time in the groups U and A. Platelet counts were significantly higher after the EHST compared to the basic levels in all the investigated groups, regardless environmental conditions and acclimatization state. Antithrombin levels were not affected by EHST whatsoever. Conclusion. In the trained soldiers, physiological heat stress caused mild changes in some serum parameters of blood clotting such as prothrombin time, while others such as antithrombin levels were not affected. Platelet counts were increased after EHST in all groups. A 10-day passive or active acclimatization in climatic chamber showed no effect on parameters investigated.

  5. Physiological Acoustics

    Science.gov (United States)

    Young, Eric D.

    The analysis of physiological sound in the peripheral auditory system solves three important problems. First, sound energy impinging on the head must be captured and presented to the transduction apparatus in the ear as a suitable mechanical signal; second, this mechanical signal needs to be transduced into a neural representation that can be used by the brain; third, the resulting neural representation needs to be analyzed by central neurons to extract information useful to the animal. This chapter provides an overview of some aspects of the first two of these processes. The description is entirely focused on the mammalian auditory system, primarily on human hearing and on the hearing of a few commonly used laboratory animals (mainly rodents and carnivores). Useful summaries of non-mammalian hearing are available [1]. Because of the large size of the literature, review papers are referenced wherever possible.

  6. Can emotive imagery aid in tolerating exertion efficiently?

    Science.gov (United States)

    Coote, D; Tenenbaum, G

    1998-12-01

    The study examined the role of relaxation and aggressive types of imagery and the effect of goal orientations, self efficacy, self control, and determination on exertion tolerance. the participants underwent an exertive task in which they were required to squeeze a dynamometer, at 50% of their maximal hand-grip capacity, for as long as they could. Perceived exertion was measured every 15 sec during the task. The time that elapsed between rating exertion as "strong", and dropping the handbar under 10% of the designated 50% criterion, was considered as the "zone of exertion tolerance". forty-eight female university students were randomly assigned into 3 groups. two imagery techniques, one under relaxing and one under aggressive conditions were taught and then applied. In the control condition, discussions were conducted. traits such as goal orientation (task and ego), physical self-efficacy and self-control were measured prior to performing the task, while rate of perceived exertion task-specific determination (i.e., task-related confidence, commitment, exertion tolerance, and effort investment) were measured before, during and after the task. The results showed an average of 31% and 28% increase in exertion tolerance in participants who used aggressive and relaxation imagery techniques respectively, compared to 4% reduction in the controls. RM ANOVA indicated equality between the two imagery groups but both were significantly different from the control group. Physical self-efficacy, self-control, and task-specific determination were found nonsignificant, but their important roles in coping with aversive stimuli are highlighted. It was evident that the "coping" mechanism rather than the "distraction" mechanism accounted for the larger sustain in the "zone of exertion tolerance". Imagery can be used efficiently in exertion tolerance but more studies are needed on athletes.

  7. Respiratory frequency is strongly associated with perceived exertion during time trials of different duration

    OpenAIRE

    Nicolò, Andrea; Marcora, Samuele Maria; Sacchetti, Massimo

    2016-01-01

    In order to provide further insight into the link between respiratory frequency (fR) and the rating of perceived exertion (RPE), the present study investigated the effect of exercise duration on perceptual and physiological responses during self-paced exercise. Nine well-trained competitive male cyclists (23 ± 3 years) performed a preliminary incremental ramp test and three randomised self-paced time trials (TTs) differing in exercise duration (10, 20 and 30 min). Both RPE and fR increased al...

  8. Physiological Studies of Lactococcus lactis

    DEFF Research Database (Denmark)

    Hansen, Gunda

    was found to facilitate the differentiation and accurate quantification of L. lactis cells in different physiological states, which agreed with the reproductive viability of reference samples and of exponential cells. The high viability of one particular L. lactis strain demonstrated its robustness during......, cell size comparison and pHi determination reflected the increasing physiological impairment during this accelerated stability test, while a preincubation in buffer led to inconsistent flow cytometric results. The comparison of reproductive and growth-independent viability suggested the presence......Aiming at a superior performance, survival and stability of dairy starter cultures requires deeper insights into physiological dynamics and relationships. This PhD thesis contributes to a more comprehensive physiological understanding of Lactococcus lactis under conditions encountered during...

  9. Exertional desaturation in patients with chronic obstructive pulmonary disease.

    Science.gov (United States)

    Panos, Ralph J; Eschenbacher, William

    2009-12-01

    Although the Centers for Medicare and Medicaid Services oxygen prescription guidelines utilize a threshold arterial oxygen tension patients with chronic obstructive pulmonary disease (COPD). There is no uniform definition of exertional hypoxemia or standardized exercise protocol to elicit decreases in oxygen levels in individuals with COPD. The causes for exertional desaturation in patients with COPD are multifactorial with ventilation-perfusion mismatching, diffusion-type limitation, shunting and reduced oxygen content of mixed venous blood all contributing to some degree. Neither resting oxygen saturation nor pulmonary function studies can reliably predict which patients with COPD will develop exertional desaturation. However, preserved pulmonary function, especially diffusing capacity, reliably predicts which patients with COPD will sustain oxygenation during exercise. Although exertional desaturation in patients with COPD appears to portend a poor prognosis, there is no evidence that maintenance of normoxemia during exercise improves the survival of these patients. Studies of the effect of supplemental oxygen on exercise performance in individuals with COPD who desaturate with exertion have yielded conflicting results. The use of short-term or "burst" oxygen either prior to or after exertion may not have significant clinical benefit. Differences in the definition of desaturation, mode of exercise, and characteristics of the patient population make it difficult to compare studies of exertional desaturation and its treatment and to determine their applicability to clinical practice.

  10. Surgical management of exertional anterior compartment syndrome of the leg.

    Science.gov (United States)

    Ali, T; Mohammed, F; Mencia, M; Maharaj, D; Hoford, R

    2013-07-01

    To describe the characteristic presentation of exertional leg pain in athletes and to discuss the diagnostic options and surgical management of exertional anterior compartment syndrome of the leg in this group of patients. Data from a series of athletes presenting with exertional leg pain were analysed and categorized according to aetiology. Sixty-six athletes presenting with exertional leg pain in 102 limbs were analysed. Sixteen patients in a first group of 20 patients with a provisional diagnosis of exertional anterior compartment syndrome of the leg underwent a closed fasciotomy with complete resolution of symptoms. A second group of 42 patients were diagnosed as medial tibial stress syndrome and a third group of four patients had confirmed stress fracture of the tibia. Exertional leg pain is a common presenting complaint of athletes to sports physicians and physiotherapists. Careful analysis can lead to an accurate diagnosis and commencement of effective treatment. Exertional anterior compartment syndrome can be successfully treated utilizing a closed fasciotomy with a rapid return to sport.

  11. Space Physiology within an Exercise Physiology Curriculum

    Science.gov (United States)

    Carter, Jason R.; West, John B.

    2013-01-01

    Compare and contrast strategies remain common pedagogical practices within physiological education. With the support of an American Physiological Society Teaching Career Enhancement Award, we have developed a junior- or senior-level undergraduate curriculum for exercise physiology that compares and contrasts the physiological adaptations of…

  12. Swimming physiology.

    Science.gov (United States)

    Holmér, I

    1992-05-01

    Swimming takes place in a medium, that presents different gravitational and resistive forces, respiratory conditions and thermal stress compared to air. The energy cost of propulsion in swimming is high, but a considerable reduction occurs at a given velocity as result of regular swim training. In medley swimmers the energy cost is lowest for front crawl, followed by backstroke, butterfly and breast-stroke. Cardiac output is probably not limiting for performance since swimmers easily achieve higher values during running. Maximal heart rate, however, is lowered by approx. 10 beats/min during swimming compared to running. Most likely active muscle mass is smaller and rate of power production lesser in swimming. Local factors, such as peripheral circulation, capillary density, perfusion pressure and metabolic capacity of active muscles, are important determinants of the power production capacity and emphasize the role of swim specific training movements. Improved swimming technique and efficiency are likely to explain much of the continuous progress in performance. Rational principles based on improved understanding of the biomechanics and physiology of swimming should be guidelines for swimmers and coaches in their efforts to explore the limits of human performance.

  13. Psycho-physiological response of soldiers in urban combat

    Directory of Open Access Journals (Sweden)

    Vicente J. Clemente-Suárez

    2013-05-01

    Full Text Available Current armed conflicts are asymmetrical and are developed m urban areas. These new requirements have not been studied for current literature. The aim of this study was to analyse changes in cortical arousal, blood lactate, muscle strength, autonomic modulation and rate of perceived exertion in a simulated urban combat. We analyzed 20 soldiers before and after an urban combat simulation. The results showed how urban combat produced high sympathetic nervous system activation, increasing the muscle strength, heart rate and blood lactate concentration of the soldiers. Despite this effort, rate of perceived exertion were not consistent with the physiological response that soldiers presented, the rate of perceived exertion was lower than the physiological response evaluated. Furthermore, the information processing and cortical arousal decreased after the urban combat simulation. These results have showed the psycho-physiological response of soldiers in combat, helping to better understanding and enabling an improvement of current training methods of soldiers.

  14. [Endoscopic aponeurotomy for chronic exertional compartmental syndrome of the forearm: report of 41 cases].

    Science.gov (United States)

    Fontes, D; Clement, R; Roure, P

    2003-08-01

    Chronic exertional compartment syndrome of the forearm is probably underdiagnosed as a cause of forearm pain in the sportsman. Its pathological basis is a critical elevation of extracellular pressure. The clinical diagnosis is confirmed by measurements of intracompartmental pressures. We described a reliable original method of endoscopically assisted superficial fasciotomy for treating chronic exertional compartment syndrome of the forearm. The goal of the study is the physiological and clinical validation of this technique. Retrospective cohort study after the anatomical assessment of the feasibility of our endoscopically assisted fasciotomy. Review of 41 forearm decompressions in 25 patients (23 sportsmen and 2 musicians). Follow-up of 6 months to 9 years. Eighty-eight percent reported an excellent or good outcome with significant reduction of pain during exercise. Three patients noted the return of their compartment syndrome and this was confirmed by new measurements of intramuscular pressure. Two of them underwent fasciectomy with excision of a hypertrophic scar of the superficial aponevrosis to good effect. Two hematomas and 2 lateral epicondylitis with no adverse effect on the final result. Endoscopically assisted fasciotomy is a reliable technique for reducing pain in chronic compartment exertional syndromes. It allows the large majority of patients to return to sports. It is our first choice indication in young sportsmen for syndromes of the forearm (anterior and/or posterior compartment). The limit of the technique is the current knowledge of collagenic tissues pathology as a cause of recurrence with hypertrophic aponevrotic scars.

  15. Caffeine and theanine exert opposite effects on attention under emotional arousal.

    Science.gov (United States)

    Giles, Grace E; Mahoney, Caroline R; Brunyé, Tad T; Taylor, Holly A; Kanarek, Robin B

    2017-01-01

    Tea is perceived as more relaxing than coffee, even though both contain caffeine. L-theanine in tea may account for the difference. Consumed together, caffeine and theanine exert similar cognitive effects to that of caffeine alone, but exert opposite effects on arousal, in that caffeine accentuates and theanine mitigates physiological and felt stress responses. We evaluated whether caffeine and theanine influenced cognition under emotional arousal. Using a double-blind, repeated-measures design, 36 participants received 4 treatments (200 mg caffeine + 0 mg theanine, 0 mg caffeine + 200 mg theanine, 200 mg caffeine + 200 mg theanine, 0 mg caffeine + 0 mg theanine) on separate days. Emotional arousal was induced by highly arousing negative film clips and pictures. Mood, salivary cortisol, and visual attention were evaluated. Caffeine accentuated global processing of visual attention on the hierarchical shape task (p Caffeine reduced flanker conflict difference scores on the Attention Network Test (p caffeine and theanine exert opposite effects on certain attentional processes, but when consumed together, they counteract the effects of each other.

  16. 20 CFR 220.132 - Physical exertion requirements.

    Science.gov (United States)

    2010-04-01

    ... determine the physical exertion requirements of work in the national economy, jobs are classified as... determinations the Board uses the following definitions: (a) Sedentary work. Sedentary work involves lifting no...

  17. Musical agency reduces perceived exertion during strenuous physical performance

    OpenAIRE

    Fritz, T; Hardikar, S.; Demoucron, M.; Niessen, M.; Demey, M.; O. Giot; Li, Y.; Haynes, J; Villringer, A; Leman, M.

    2013-01-01

    Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from i...

  18. Musical agency reduces perceived exertion during strenuous physical performance.

    Science.gov (United States)

    Fritz, Thomas Hans; Hardikar, Samyogita; Demoucron, Matthias; Niessen, Margot; Demey, Michiel; Giot, Olivier; Li, Yongming; Haynes, John-Dylan; Villringer, Arno; Leman, Marc

    2013-10-29

    Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from it. For this we measured psychologically indicated exertion during physical workout with and without musical agency while simultaneously acquiring metabolic values with spirometry. Results showed that musical agency significantly decreased perceived exertion during workout, indicating that musical agency may actually facilitate physically strenuous activities. This indicates that the positive effect of music on perceived exertion cannot always be explained by an effect of diversion from proprioceptive feedback. Furthermore, this finding suggests that the down-modulating effect of musical agency on perceived exertion may be a previously unacknowledged driving force for the development of music in humans: making music makes strenuous physical activities less exhausting.

  19. Do placebo expectations influence perceived exertion during physical exercise?

    Science.gov (United States)

    Mothes, Hendrik; Leukel, Christian; Seelig, Harald; Fuchs, Reinhard

    2017-01-01

    This study investigates the role of placebo expectations in individuals' perception of exertion during acute physical exercise. Building upon findings from placebo and marketing research, we examined how perceived exertion is affected by expectations regarding a) the effects of exercise and b) the effects of the exercise product worn during the exercise. We also investigated whether these effects are moderated by physical self-concept. Seventy-eight participants conducted a moderate 30 min cycling exercise on an ergometer, with perceived exertion (RPE) measured every 5 minutes. Beforehand, each participant was randomly assigned to 1 of 4 conditions and watched a corresponding film clip presenting "scientific evidence" that the exercise would or would not result in health benefits and that the exercise product they were wearing (compression garment) would additionally enhance exercise benefits or would only be worn for control purposes. Participants' physical self-concept was assessed via questionnaire. Results partially demonstrated that participants with more positive expectations experienced reduced perceived exertion during the exercise. Furthermore, our results indicate a moderator effect of physical self-concept: Individuals with a high physical self-concept benefited (in terms of reduced perceived exertion levels) in particular from an induction of generally positive expectations. In contrast, individuals with a low physical self-concept benefited when positive expectations were related to the exercise product they were wearing. In sum, these results suggest that placebo expectations may be a further, previously neglected class of psychological factors that influence the perception of exertion.

  20. Musical agency reduces perceived exertion during strenuous physical performance

    Science.gov (United States)

    Fritz, Thomas Hans; Hardikar, Samyogita; Demoucron, Matthias; Niessen, Margot; Demey, Michiel; Giot, Olivier; Li, Yongming; Haynes, John-Dylan; Villringer, Arno; Leman, Marc

    2013-01-01

    Music is known to be capable of reducing perceived exertion during strenuous physical activity. The current interpretation of this modulating effect of music is that music may be perceived as a diversion from unpleasant proprioceptive sensations that go along with exhaustion. Here we investigated the effects of music on perceived exertion during a physically strenuous task, varying musical agency, a task that relies on the experience of body proprioception, rather than simply diverting from it. For this we measured psychologically indicated exertion during physical workout with and without musical agency while simultaneously acquiring metabolic values with spirometry. Results showed that musical agency significantly decreased perceived exertion during workout, indicating that musical agency may actually facilitate physically strenuous activities. This indicates that the positive effect of music on perceived exertion cannot always be explained by an effect of diversion from proprioceptive feedback. Furthermore, this finding suggests that the down-modulating effect of musical agency on perceived exertion may be a previously unacknowledged driving force for the development of music in humans: making music makes strenuous physical activities less exhausting. PMID:24127588

  1. Cross-sectional assessment of exertional dyspnea in otherwise healthy children.

    Science.gov (United States)

    Mahut, Bruno; Fuchs-Climent, Deborah; Plantier, Laurent; Karila, Chantal; Refabert, Luc; Chevalier-Bidaud, Brigitte; Beydon, Nicole; Peiffer, Claudine; Delclaux, Christophe

    2014-08-01

    Exertional dyspnea during sport at school in children with asthma or in otherwise healthy children is commonly attributed to exercise-induced asthma (EIA), but when a short-acting beta agonist (SABA) trial fails to improve symptoms the physician is often at a loose end. The aims were to prospectively assess the causes of exertional dyspnea in children/adolescents with or without asthma using a cardiopulmonary exercise test while receiving a SABA and to assess the effects of standardized breathing/reassurance therapy. Seventy-nine patients (12.2 ± 2.3 years, 41 girls, 49 with previously diagnosed asthma) with dyspnea unresponsive to SABA were prospectively included. Exercise test outcomes depicted normal or subnormal performance with normal ventilatory demand and capacity in 53/79 children (67%) defining a physiological response. The remaining 26 children had altered capacity (resistant EIA [n = 17, 9 with previous asthma diagnosis], vocal cord dysfunction [n = 2]) and/or increased demand (alveolar hyperventilation [n = 3], poor conditioning [n = 7]). Forty-two children who had similar characteristics than the remaining 37 children underwent the two sessions of standardized reassurance therapy. They all demonstrated an improvement that was rated "large." The degree of improvement correlated with % predicted peak V'O2 (r = -0.37, P = 0.015) and peak oxygen pulse (r = -0.45, P = 0.003), whatever the underlying dyspnea cause. It suggested a higher benefit in those with poorer conditioning condition. The most frequent finding in children/adolescents with mild exertional dyspnea unresponsive to preventive SABA is a physiological response to exercise, and standardized reassurance afforded early clinical improvement, irrespective of the dyspnea cause. © 2013 Wiley Periodicals, Inc.

  2. Assessment of the toxic effect exerted by fluorescent pseudomonads on embryos and larvae of the sea urchin Strongylocentrotus nudus.

    Science.gov (United States)

    Beleneva, I A; Shamshurina, E V; Eliseikina, M G

    2015-05-01

    Strains of bacteria capable of growing on artificial culture media were isolated from the fouling of brass plates submerged in Nha Trang Bay, South China Sea, and from tissues of the seastar Distolasterias nipon, caught in Peter the Great Bay, Sea of Japan. According to the complex of data of genetic and physiological/biochemical analyzes, two strains of cultivated bacteria were identified by us as the species Pseudomonas aeruginosa, two strains as Pseudomonas fluorescens, and one strain as Ruegeria sp. It was shown that the cultivated strains of P. aeruginosa released exotoxins, particularly phenazine pigments, into the environment. Production of the toxins did not depend on presence of a target organism in the system and was aimed at regulation of interactions in the microbial community. The toxicity of the studied natural isolates of fluorescent pseudomonads was analyzed by using embryos and larvae of the sea urchin Strongylocentrotus nudus, which are the sensitive and dynamic toxicological sea-urchin embryo test (SET) system. As was established, exotoxins produced by the strains of P. aeruginosa inhibit activity of cilia in sea urchin larvae, as well as disturb processes of cell differentiation in embryos and larvae. Their toxic influence is accompanied by disturbances of protein synthesis and the disruptions of cytoskeleton in the course of zygote cleavage and larval development. Unlike P. aeruginosa, the strains of P. fluorescens and Ruegeria sp. did not exert the toxic effect on SET. The obtained data allow considering objects of the environment as the natural reservoir of opportunistic microorganisms posing a potential threat to human, whereas the use of SET for determination of toxicity of isolated bacteria provides an opportunity to study the mechanisms of their interactions with organisms in marine ecosystems. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. [Human physiology: kidney].

    Science.gov (United States)

    Natochin, Iu V

    2010-01-01

    The content of human physiology as an independent part of current physiology is discussed. Substantiated is the point that subjects of human physiology are not only special sections of physiology where functions are inherent only in human (physiology of intellectual activity, speech, labor, sport), but also in peculiarities of functions, specificity of regulation of each of physiological systems. By the example of physiology of kidney and water-salt balance there are shown borders of norm, peculiarities of regulation in human, new chapters of renal physiology which have appeared in connection with achievements of molecular physiology.

  4. Challenging Return to Play Decisions: Heat Stroke, Exertional Rhabdomyolysis, and Exertional Collapse Associated With Sickle Cell Trait.

    Science.gov (United States)

    Asplund, Chad A; O'Connor, Francis G

    2016-01-01

    Sports medicine providers frequently return athletes to play after sports-related injuries and conditions. Many of these conditions have guidelines or medical evidence to guide the decision-making process. Occasionally, however, sports medicine providers are challenged with complex medical conditions for which there is little evidence-based guidance and physicians are instructed to individualize treatment; included in this group of conditions are exertional heat stroke (EHS), exertional rhabdomyolysis (ER), and exertional collapse associated with sickle cell trait (ECAST). The MEDLINE (2000-2015) database was searched using the following search terms: exertional heat stroke, exertional rhabdomyolysis, and exertional collapse associated with sickle cell trait. References from consensus statements, review articles, and book chapters were also utilized. Clinical review. Level 4. These entities are unique in that they may cause organ system damage capable of leading to short- or long-term detriments to physical activity and may not lend to complete recovery, potentially putting the athlete at risk with premature return to play. With a better understanding of the pathophysiology of EHS, ER, and ECAST and the factors associated with recovery, better decisions regarding return to play may be made. © 2015 The Author(s).

  5. Smolt physiology and endocrinology

    Science.gov (United States)

    McCormick, Stephen D.; McCormick, Stephen D.; Farrell, Anthony Peter; Brauner, Colin J.

    2013-01-01

    Hormones play a critical role in maintaining body fluid balance in euryhaline fishes during changes in environmental salinity. The neuroendocrine axis senses osmotic and ionic changes, then signals and coordinates tissue-specific responses to regulate water and ion fluxes. Rapid-acting hormones, e.g. angiotensins, cope with immediate challenges by controlling drinking rate and the activity of ion transporters in the gill, gut, and kidney. Slow-acting hormones, e.g. prolactin and growth hormone/insulin-like growth factor-1, reorganize the body for long-term acclimation by altering the abundance of ion transporters and through cell proliferation and differentiation of ionocytes and other osmoregulatory cells. Euryhaline species exist in all groups of fish, including cyclostomes, and cartilaginous and teleost fishes. The diverse strategies for responding to changes in salinity have led to differential regulation and tissue-specific effects of hormones. Combining traditional physiological approaches with genomic, transcriptomic, and proteomic analyses will elucidate the patterns and diversity of the endocrine control of euryhalinity.

  6. Influence of acclimatization on serum enzyme changes in soldiers during exertional heat stress

    Directory of Open Access Journals (Sweden)

    Radaković Sonja

    2009-01-01

    Full Text Available Background/Aim. Exertional heat stress is common problem in military services. The aim was to examine changes in serum concentrations of some enzymes in soldiers during exertional heat stress test (EHST as well as the effects of 10-days passive or active acclimatization in climatic chamber. Methods. Forty male soldiers with high aerobic capacity, performed EHST either in cool (20 ºC, 16 ºC Wet bulb globe temperature - WBGT, or hot (40 ºC, 25 ºC WBGT environment, unacclimatized, or after 10 days of passive or active acclimation. Physiological strain was measured by tympanic temperatures (Tty and heart rates (HR. Concentrations of alanine aminotransferase (ALT and aspartate aminotransferase (AST, lactate dehydrogenase (LDH, and creatine-kinase (CK were measured in blood samples collected before and immediately after EHST. Results. Exertional heat stress test in hot conditions induced physiological heat stress (increase in Tty and HR, with significant increase in concentrations of all enzymes in unacclimatized group: ALT (42.5 ± 4.2 before vs 48.1 ± 3.75 U/L after EHST, p < 0.01, AST (24.9 ± 5.1 vs 33.4 ± 4.48 U/L, p < 0.01, LDH (160.6 ± 20.2 vs 195.7 ± 22.6 U/L, p < 0.001 and CK (215.5 ± 91.2 vs 279.1 ± 117.5 U/L, p < 0.05. In acclimatized soldiers there were no significant changes in concentrations of ALT and AST, while concentration of CK was significantly higher. Concentrations of LDH were significantly higher in all investigated groups, regardless of temperature conditions. Conclusion. In trained soldiers, 10-days passive or active acclimatization in climatic chamber can prevent increase in serum concentrations of ALT and AST, induced by exertional heat stress. Increase of serum concentrations of CK and LDH was induced by physical strain itself, with no additional effect of heat stress.

  7. An Experimental Study in Generative Music for Exercising to Ease Perceived Exertion by use of Heart Beat Rate as a Control Parameter

    DEFF Research Database (Denmark)

    Serafin, Stefania; Erkut, Cumhur

    This paper investigates whether generative music, adapted to a user's heart beat rate, can be used to ease the perceived exertion. A generative system was implemented and tested on 13 test participants in a controlled environment on a training bike. The test participants performed a cycling workout...... of three minutes in two conditions in a self-chosen pace, with and without music. Their pulse were used as the physiological exertion. The perceived exertion was rated by the test participants according to Borg’s 6-20 exertion scale. Five out of 13 participants showed indications supporting the notion......, while 2 out of 13 indicated the opposite. 6 out of 13 participants neither showed indications supporting nor opposing the theory. The results could be useful for exercises, where the change of heart pulse is gradual, but further work is needed in cadance-based exercises....

  8. Mechanochemistry Induced Using Force Exerted by a Functionalized Microscope Tip

    DEFF Research Database (Denmark)

    Zhang, Yajie; Wang, Yongfeng; Lü, Jing-Tao

    2017-01-01

    Atomic-scale mechanochemistry is realized from force exerted by a C60 -functionalized scanning tunneling microscope tip. Two conformers of tin phthalocyanine can be prepared on coinage-metal surfaces. A transition between these conformers is induced on Cu(111) and Ag(100). Density-functional calc......Atomic-scale mechanochemistry is realized from force exerted by a C60 -functionalized scanning tunneling microscope tip. Two conformers of tin phthalocyanine can be prepared on coinage-metal surfaces. A transition between these conformers is induced on Cu(111) and Ag(100). Density...

  9. Platelet-rich plasma exerts antinociceptive activity by a peripheral endocannabinoid-related mechanism.

    Science.gov (United States)

    Descalzi, Fiorella; Ulivi, Valentina; Cancedda, Ranieri; Piscitelli, Fabiana; Luongo, Livio; Guida, Francesca; Gatta, Luisa; Maione, Sabatino; Di Marzo, Vincenzo

    2013-10-01

    In regenerative medicine, platelet by-products containing factors physiologically involved in wound healing, have been successfully used in the form of platelet-rich plasma (PRP) for the topical therapy of various clinical conditions since it produces an improvement in tissue repair as well as analgesic effects. Measurement of endocannabinoids and related compounds in PRP revealed the presence of a significant amount of anandamide, 2-arachidonoylglycerol, palmitoylethanolamide, and oleoylethanolamide. Investigation of the activity of PRP on the keratinocyte cell line NCTC2544 in physiological and inflammatory conditions showed that, under inflammatory conditions, PRP induced in a statistically significant manner the production of these compounds by the cells suggesting that PRP might induce the production of these analgesic mediators particularly in the physiologically inflamed wounded tissue. Studies in a mouse model of acute inflammatory pain induced by formalin injection demonstrated a potent antinociceptive effect against both early and late nocifensive responses. This effect was observed following intrapaw injection of (1) total PRP; (2) lipids extracted from PRP; and (3) an endocannabinoid-enriched lipid fraction of PRP. In all conditions, antagonists of endocannabinoid CB1 and CB2 receptors, injected in the paw, abrogated the antinociceptive effects strongly suggesting for this preparation a peripheral mechanism of action. In conclusion, we showed that PRP and PRP lipid extract exert a potent antinociceptive activity linked, at least in part, to their endocannabinoids and related compound content, and to their capability of elevating the levels of these lipid mediators in cells.

  10. Modulation of GABAergic transmission in development and neurodevelopmental disorders: investigating physiology and pathology to gain therapeutic perspectives.

    Science.gov (United States)

    Deidda, Gabriele; Bozarth, Ignacio F; Cancedda, Laura

    2014-01-01

    During mammalian ontogenesis, the neurotransmitter GABA is a fundamental regulator of neuronal networks. In neuronal development, GABAergic signaling regulates neural proliferation, migration, differentiation, and neuronal-network wiring. In the adult, GABA orchestrates the activity of different neuronal cell-types largely interconnected, by powerfully modulating synaptic activity. GABA exerts these functions by binding to chloride-permeable ionotropic GABAA receptors and metabotropic GABAB receptors. According to its functional importance during development, GABA is implicated in a number of neurodevelopmental disorders such as autism, Fragile X, Rett syndrome, Down syndrome, schizophrenia, Tourette's syndrome and neurofibromatosis. The strength and polarity of GABAergic transmission is continuously modulated during physiological, but also pathological conditions. For GABAergic transmission through GABAA receptors, strength regulation is achieved by different mechanisms such as modulation of GABAA receptors themselves, variation of intracellular chloride concentration, and alteration in GABA metabolism. In the never-ending effort to find possible treatments for GABA-related neurological diseases, of great importance would be modulating GABAergic transmission in a safe and possibly physiological way, without the dangers of either silencing network activity or causing epileptic seizures. In this review, we will discuss the different ways to modulate GABAergic transmission normally at work both during physiological and pathological conditions. Our aim is to highlight new research perspectives for therapeutic treatments that reinstate natural and physiological brain functions in neuro-pathological conditions.

  11. Modulation of GABAergic Transmission in Development and Neurodevelopmental Disorders: Investigating Physiology and Pathology to Gain Therapeutic Perspectives

    Directory of Open Access Journals (Sweden)

    Gabriele eDeidda

    2014-05-01

    Full Text Available During mammalian ontogenesis, the neurotransmitter GABA is a fundamental regulator of neuronal networks. In neuronal development, GABAergic signaling regulates neural proliferation, migration, differentiation, and neuronal-network wiring. In the adult, GABA orchestrates the activity of different neuronal cell-types largely interconnected, by powerfully modulating synaptic activity. GABA exerts these functions by binding to chloride-permeable ionotropic GABAA receptors and metabotropic GABAB receptors. According to its functional importance during development, GABA is implicated in a number of neurodevelopmental disorders such as autism, Fragile X, Rett syndrome, Down syndrome, schizophrenia, Tourette's syndrome and neurofibromatosis.The strength and polarity of GABAergic transmission is continuously modulated during physiological, but also pathological conditions. For GABAergic transmission through GABAA receptors, strength regulation is achieved by different mechanisms such as modulation of GABAA receptors themselves, variation of intracellular chloride concentration, and alteration in GABA metabolism. In the never-ending effort to find possible treatments for GABA-related neurological diseases, of great importance would be modulating GABAergic transmission in a safe and possibly physiological way, without the dangers of either silencing network activity or causing epileptic seizures. In this review, we will discuss the different ways to modulate GABAergic transmission normally at work both during physiological and pathological conditions. Our aim is to highlight new research perspectives for therapeutic treatments that reinstate natural and physiological brain functions in neuro-pathological conditions.

  12. 20 CFR 220.135 - Exertional and nonexertional limitations.

    Science.gov (United States)

    2010-04-01

    ... Department of Labor, to determine the exertional requirements of work which exists in the national economy... other work which exists in the national economy in order to decide whether the claimant is disabled or... functioning because the claimant is nervous, anxious, or depressed; (ii) Difficulty maintaining attention or...

  13. Exertional abdominal pain as a symptom of secondary pulmonary ...

    African Journals Online (AJOL)

    2011-04-21

    Apr 21, 2011 ... We report a rare presentation of mitral stenosis (MS). MS is a common valvular disease, the first manifestation of which is usually easy fatigability and exertional dyspnea. As the disease progresses in severity, other signs and symptoms appear, such as orthopnea, hemoptysis, and peripheral edema. This is ...

  14. Identification of training status differences using perceived exertion threshold.

    Science.gov (United States)

    Ferreira, Guilherme A; Bertuzzi, Romulo; Lima-Silva, Adriano E; Malfatti, Carlos; De-Oliveira, Fernando R; Osiecki, Raul

    2016-04-01

    We investigated if the rate of perceived exertion (RPE) threshold is as sensitive as the lactate threshold to detect training differences. Lactate and RPE thresholds were identified in well-trained cyclists and physically active males. Power output was higher in well-trained cyclists than in physically active individuals for both thresholds (p trained cyclists and physically active individuals.

  15. Chronic exertional compartment syndrome in the forearm of a rower ...

    African Journals Online (AJOL)

    This case report describes chronic exertional compartment syndrome in the forearm of a professional rower. We consider this to be a rare anatomical location for this type of syndrome. Morever, not much is known about its clinical presentation and the subsequent optimal medical management thereof.

  16. Exertional abdominal pain as a symptom of secondary pulmonary ...

    African Journals Online (AJOL)

    2011-04-21

    Apr 21, 2011 ... Nigerian Journal of Clinical Practice • Jan-Mar 2013 • Vol 16 • Issue 1. Case Report. Exertional abdominal pain as a symptom of secondary pulmonary hypertension in mitral stenosis. J Najafian, N Toghianifar, A Khosravi. Department of cardiology, Isfahan Cardiovascular Research Center, Isfahan ...

  17. Measurement and Relation between Received and Exerted Violence against Partner

    Directory of Open Access Journals (Sweden)

    José Moral de la Rubia

    2014-07-01

    Full Text Available A female victimization model is often assumed in the study of couple violence, even in general population. In Mexico, a questionnaire of couple violence has been developed. This instrument evaluates suffered and exerted violence. The aims of this paper were to contrast the factor structure of this questionnaire, calculate its internal consistency, describe its distributions, compare means of violence between both sexes and between persons who live or not with their partners, and study the relationship between received and exerted violence. A non-experimental research with a trans-sectional design was performed. The questionnaire was applied to a non probability sample of 223 women and 177 men with heterosexual couples from general population. Confirmatory factor analysis and structural equation modeling were used for data analysis. The factor structure of received violence scale was one-dimensional, and the one of exerted violence scale was two-dimensional. Both sexes reported to exert violence with the same frequency, but men complained to receive violence with more frequency than women. Persons who live with their partners reported to receive more violence and to exert more non-psychological violence than persons who do not live with their partners. The correlations between received and exercised violence were moderate. A recursive model of violent reaction showed a fit to data from good to adequate, and had good properties of invariance between both sexes, and between persons who live or not with their partners. It is concluded that the questionnaire has good properties of factor structure and internal consistency, and data refute a model of female victimization.

  18. Effect of experimental modulation of mood on perception of exertional dyspnea in healthy subjects.

    Science.gov (United States)

    Sharma, Pramod; Morris, Norman R; Adams, Lewis

    2016-01-15

    In many diseases across a range of pathologies (e.g., cardiopulmonary, neuromuscular, and cancer), chronic dyspnea, particularly on exertion, is a major debilitating symptom often associated with clinical anxiety/depression. This study aims to explore the interaction between mood state and exertional dyspnea in a healthy population. Following familiarization, 20 healthy subjects (27-54 years old) performed six 5-min treadmill tests on three separate days. On each day subjects viewed randomly assigned images designed to induce positive, negative, or neutral mood states (International Affective Picture System). For each condition, at minute intervals, subjects rated dyspnea (sensory and affective domains) in the first test and mood (valence and arousal domains) in the second test. Oxygen uptake (V̇O2 , liters/min), carbon dioxide production (V̇CO2, liters/min), ventilation (V̇E, liters/min), respiratory frequency (f(R), beats/min), and heart rate (HR, bpm), were measured throughout the exercise. V̇O2, V̇CO2, V̇E, HR, and f(R) were not statistically significantly different among the three mood states (P > 0.05). Mood valence was significantly higher with parallel viewing of positive (last 2-min mean ± SE = 6.9 ± 0.2) compared with negative pictures (2.4 ± 0.2; P negative (sensory: 5.6 ± 0.3; affective: 3.3 ± 0.5) compared with positive mood (sensory: 4.4 ± 0.4, P positive mood alleviates both the sensory and affective domains of exertional dyspnea in healthy subjects. Thus the treatment of anxiety/depression in dyspenic populations could be a worthwhile therapeutic strategy in increasing symptom-limited exercise tolerance, thereby contributing to improved quality of life. Copyright © 2016 the American Physiological Society.

  19. Blue-light irradiation regulates proliferation and differentiation in human skin cells.

    Science.gov (United States)

    Liebmann, Joerg; Born, Matthias; Kolb-Bachofen, Victoria

    2010-01-01

    Sunlight influences the physiology of the human skin in beneficial as well as harmful ways, as has been shown for UV light. However, little is known about the effects of other wavelengths of solar irradiation. In this study we irradiated human keratinocytes and skin-derived endothelial cells with light-emitting-diode devices of distinct wavelengths to study the effects on cell physiology. We found that light at wavelengths of 632-940 nm has no effect, but irradiation with blue light at 412-426 nm exerts toxic effects at high fluences. Light at 453 nm is nontoxic up to a fluence of 500 J/cm(2). At nontoxic fluences, blue light reduces proliferation dose dependently by up to 50%, which is attributable to differentiation induction as shown by an increase of differentiation markers. Experiments with BSA demonstrate that blue-light irradiation up to 453 nm photolytically generates nitric oxide (NO) from nitrosated proteins, which is known to initiate differentiation in skin cells. Our data provide evidence for a molecular mechanism by which blue light may be effective in treating hyperproliferative skin conditions by reducing proliferation due to the induction of differentiation. We observed a photolytic release of NO from nitrosated proteins, indicating that they are light acceptors and signal transducers up to a wavelength of 453 nm.

  20. Menstrual cycle effects on perceived exertion and pain during exercise among sedentary women.

    Science.gov (United States)

    Hooper, Ann E Caldwell; Bryan, Angela D; Eaton, Melissa

    2011-03-01

    Increasing cardiovascular fitness through exercise participation among sedentary people is important for decreasing all-cause mortality. From an intervention perspective, identifying modifiable factors that maximize the successful initiation of exercise is of utmost importance. For women, cyclic hormonal variations can influence aspects of health and health behaviors, from smoking cessation efficacy to physiological responses to exercise. The purpose of this study was to examine the influence of menstrual cycle phase and hormonal contraceptive (HC) use on subjective response to an initial bout of moderate intensity exercise among previously sedentary women (n = 117). Women completed a treadmill exercise challenge session at 65% of their previously determined maximum oxygen consumption (Vo(2) max) during the early follicular, late follicular, or luteal phase. Participants reported ratings of perceived exertion and pain using Borg's Rating of Perceived Exertion (RPE) and CR10 scales at 10, 20, and 30 minutes during the exercise session. There was a significant menstrual phase x birth control interaction on change in RPE [F(2, 111) = 3.75, p cycle phase influence sedentary women's subjective response to exercise. These results have important implications for the timing of exercise interventions aimed at increasing exercise among sedentary women.

  1. CART neurons in the arcuate nucleus and lateral hypothalamic area exert differential controls on energy homeostasis.

    Science.gov (United States)

    Lau, Jackie; Farzi, Aitak; Qi, Yue; Heilbronn, Regine; Mietzsch, Mario; Shi, Yan-Chuan; Herzog, Herbert

    2018-01-01

    The cocaine- and amphetamine-regulated transcript (CART) codes for a pivotal neuropeptide important in the control of appetite and energy homeostasis. However, limited understanding exists for the defined effector sites underlying CART function, as discrepant effects of central CART administration have been reported. By combining Cart-cre knock-in mice with a Cart adeno-associated viral vector designed using the flip-excision switch (AAV-FLEX) technology, specific reintroduction or overexpression of CART selectively in CART neurons in the arcuate nucleus (Arc) and lateral hypothalamic area (LHA), respectively, was achieved. The effects on energy homeostasis control were investigated. Here we show that CART neuron-specific reintroduction of CART into the Arc and LHA leads to distinct effects on energy homeostasis control. Specifically, CART reintroduction into the Arc of otherwise CART-deficient Cart cre/cre mice markedly decreased fat mass and body weight, whereas CART reintroduction into the LHA caused significant fat mass gain and lean mass loss, but overall unaltered body weight. The reduced adiposity in Arc CART ;Cart cre/cre mice was associated with an increase in both energy expenditure and physical activity, along with significantly decreased Npy mRNA levels in the Arc but with no change in food consumption. Distinctively, the elevated fat mass in LHA CART ;Cart cre/cre mice was accompanied by diminished insulin responsiveness and glucose tolerance, greater spontaneous food intake, and reduced energy expenditure, which is consistent with the observed decrease of brown adipose tissue temperature. This is also in line with significantly reduced tyrosine hydroxylase (Th) and notably increased corticotropin-releasing hormone (Crh) mRNA expressions in the paraventricular nucleus (PVN). Taken together, these results identify catabolic and anabolic effects of CART in the Arc and LHA, respectively, demonstrating for the first time the distinct and region-specific functions of CART in controlling feeding and energy homeostasis. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

  2. Retinoic X receptor subtypes exert differential effects on the regulation of Trh transcription.

    Science.gov (United States)

    Decherf, Stéphanie; Seugnet, Isabelle; Becker, Nathalie; Demeneix, Barbara A; Clerget-Froidevaux, Marie-Stéphanie

    2013-12-05

    How Retinoid X receptors (RXR) and thyroid hormone receptors (TR) interact on negative TREs and whether RXR subtype specificity is determinant in such regulations is unknown. In a set of functional studies, we analyzed RXR subtype effects in T3-dependent repression of hypothalamic thyrotropin-releasing hormone (Trh). Two-hybrid screening of a hypothalamic paraventricular nucleus cDNA bank revealed specific, T3-dependent interaction of TRs with RXRβ. In vivo chromatin immuno-precipitation showed recruitment of RXRs to the TRE-site 4 region of the Trh promoter in the absence of T3. In vivo overexpression of RXRα in the mouse hypothalamus heightened T3-independent Trh transcription, whereas RXRβ overexpression abrogated this activity. Loss of function of RXRα and β by shRNAs induced inverse regulations. Thus, RXRα and RXRβ display specific roles in modulating T3-dependent regulation of Trh. These results provide insight into the actions of these different TR heterodimerization partners within the context of a negatively regulated gene. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  3. Endoscopic fasciotomy in chronic exertional compartment syndrome of the forearm caused by heavy manual work – case report

    Directory of Open Access Journals (Sweden)

    Wilmink, Beate

    2016-06-01

    Full Text Available Chronic exertional compartment syndrome (CECS of the forearm is a rare condition causing pain, tenderness, swelling, paraesthesia and muscle weakness. It is caused by a critical augmentation of the extracellular pressure of the forearm compartments induced by intensive sport or heavy manual work. This case report describes a 33-year-old demolition worker who presented with chronic exertional compartment syndrome of both forearms induced by severe physical work. The exclusion diagnosis was made based on clinical and electro-physiological examinations. The patient was treated using a minimal-invasive one portal endoscopic fasciotomy. He resumed to full work duties with no recurrence of symptoms during strain caused by heavy lifting and carrying. In conclusion, endoscopic forearm fascial release is a safe, efficient and minimally invasive technique that avoids the disadvantages associated with open decompression in cases of CECS and facilitates an early resumption of work.

  4. Endoscopic Thermal Fasciotomy for Chronic Exertional Compartment Syndrome.

    Science.gov (United States)

    Voleti, Pramod B; Lebrun, Drake G; Roth, Cameron A; Kelly, John D

    2015-10-01

    Chronic exertional compartment syndrome is an activity-induced condition that occurs when intracompartmental pressures within an osteofascial envelope increase during exercise, leading to reversible ischemic symptoms such as pain, cramping, numbness, or weakness. Nonoperative treatment options for this condition have shown limited success and are often undesirable for the patient given the requirement for activity modification. Traditional surgical treatment options involving open or subcutaneous fasciotomies have more favorable results, but these techniques are associated with significant morbidity. Endoscopically assisted fasciotomy techniques afford the advantages of being minimally invasive, providing excellent visualization, and allowing accelerated rehabilitation. The purpose of this article is to describe a technique for performing endoscopically assisted fasciotomies for chronic exertional compartment syndrome of the lower leg using an entirely endoscopic thermal ablating device. The endoscopic thermal fasciotomy technique is associated with minimal morbidity, ensures excellent hemostasis, and affords an early return to sports.

  5. Endoscopic Thermal Fasciotomy for Chronic Exertional Compartment Syndrome

    Science.gov (United States)

    Voleti, Pramod B.; Lebrun, Drake G.; Roth, Cameron A.; Kelly, John D.

    2015-01-01

    Chronic exertional compartment syndrome is an activity-induced condition that occurs when intracompartmental pressures within an osteofascial envelope increase during exercise, leading to reversible ischemic symptoms such as pain, cramping, numbness, or weakness. Nonoperative treatment options for this condition have shown limited success and are often undesirable for the patient given the requirement for activity modification. Traditional surgical treatment options involving open or subcutaneous fasciotomies have more favorable results, but these techniques are associated with significant morbidity. Endoscopically assisted fasciotomy techniques afford the advantages of being minimally invasive, providing excellent visualization, and allowing accelerated rehabilitation. The purpose of this article is to describe a technique for performing endoscopically assisted fasciotomies for chronic exertional compartment syndrome of the lower leg using an entirely endoscopic thermal ablating device. The endoscopic thermal fasciotomy technique is associated with minimal morbidity, ensures excellent hemostasis, and affords an early return to sports. PMID:26900549

  6. Two cases of exertional rhabdomyolysis precipitated by personal trainers.

    Science.gov (United States)

    Springer, Brian L; Clarkson, Priscilla M

    2003-09-01

    Numerous cases of exertional rhabdomyolysis have been reported in the literature, and these cases mostly involve individuals who were inexperienced exercisers, uneducated in fitness and health principles, dehydrated or heat stressed, taking drugs, or military recruits in basic training. The purpose of this article is to review two cases of exertional rhabdomyolysis in healthy, experienced exercisers. The cases reviewed are for a 22-yr-old female college student and a 37-yr-old male physician who presented with rhabdomyolysis secondary to exercise in a local health club that was part of a national chain. In these two cases individuals, both well educated and experienced in fitness, were encouraged by fitness instructors in a local health club to overexertion during their exercise routine leading to rhabdomyolysis.

  7. Endoscopic Thermal Fasciotomy for Chronic Exertional Compartment Syndrome

    OpenAIRE

    Voleti, Pramod B.; Lebrun, Drake G.; Roth, Cameron A.; Kelly, John D.

    2015-01-01

    Chronic exertional compartment syndrome is an activity-induced condition that occurs when intracompartmental pressures within an osteofascial envelope increase during exercise, leading to reversible ischemic symptoms such as pain, cramping, numbness, or weakness. Nonoperative treatment options for this condition have shown limited success and are often undesirable for the patient given the requirement for activity modification. Traditional surgical treatment options involving open or subcutan...

  8. Exercise, Physical Activity, and Exertion over the Business Cycle

    OpenAIRE

    Gregory J. Colman; Dhaval M. Dave

    2011-01-01

    As economic recessions reduce employment and wages, associated shifts in time and income constraints would be expected to also impact individuals' health behaviors. Prior work has focused exclusively on recreational exercise, which typically represents only about 4% of total daily physical exertion. The general presumption in these studies is that, because exercise improves health, if unemployment increases exercise it must also improve health. Yet a person may be laid off from a physically d...

  9. Perceived Exertion under Conditions of Sustained Work and Sleep Loss.

    Science.gov (United States)

    1987-03-25

    the various tasks they would be performing during testing (see Ryman et al, 1984, for details). Day 2 involved further practice with the questionaires ...34history" and methods. Medicine and Science in Sports , 5, 90-93. Gamberale, F. 1972, Perceived exertion, heart rate, oxygen uptake and blood lactate in...G.M. 1981, Exercise after sleep deprivation, Medicine and Science in Sports and Exercise, 13, 220-223. McNair, D.M., Lorr, M., and Droppleman, L.F

  10. Exercise, physical activity, and exertion over the business cycle.

    Science.gov (United States)

    Colman, Gregory; Dave, Dhaval

    2013-09-01

    Shifts in time and income constraints over economic expansions and contractions would be expected to affect individuals' behaviors. We explore the impact of the business cycle on individuals' exercise, time use, and total physical exertion, utilizing information on 112,000 individual records from the 2003-2010 American Time Use Surveys. In doing so, we test a key causal link that has been hypothesized in the relation between unemployment and health, but not heretofore assessed. Using more precise measures of exercise (and other activities) than previous studies, we find that as work-time decreases during a recession, recreational exercise, TV-watching, sleeping, childcare, and housework increase. This, however, does not compensate for the decrease in work-related exertion due to job-loss, and total physical exertion declines. These effects are strongest among low-educated men, which is validating given that employment in the Great Recession has declined most within manufacturing, mining, and construction. We also find evidence of intra-household spillover effects, wherein individuals respond to shifts in spousal employment conditional on their own labor supply. The decrease in total physical activity during recessions is especially problematic for vulnerable populations concentrated in boom-and-bust industries, and may have longer-term effects on obesity and related health outcomes. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Bile acids in regulation of intestinal physiology.

    LENUS (Irish Health Repository)

    Keating, Niamh

    2009-10-01

    In addition to their roles in facilitating lipid digestion and absorption, bile acids are recognized as important regulators of intestinal function. Exposure to bile acids can dramatically influence intestinal transport and barrier properties; in recent years, they have also become appreciated as important factors in regulating cell growth and survival. Indeed, few cells reside within the intestinal mucosa that are not altered to some degree by exposure to bile acids. The past decade saw great advances in the knowledge of how bile acids exert their actions at the cellular and molecular levels. In this review, we summarize the current understanding of the role of bile acids in regulation of intestinal physiology.

  12. Doppler radar physiological sensing

    CERN Document Server

    Lubecke, Victor M; Droitcour, Amy D; Park, Byung-Kwon; Singh, Aditya

    2016-01-01

    Presents a comprehensive description of the theory and practical implementation of Doppler radar-based physiological monitoring. This book includes an overview of current physiological monitoring techniques and explains the fundamental technology used in remote non-contact monitoring methods. Basic radio wave propagation and radar principles are introduced along with the fundamentals of physiological motion and measurement. Specific design and implementation considerations for physiological monitoring radar systems are then discussed in detail. The authors address current research and commercial development of Doppler radar based physiological monitoring for healthcare and other applications.

  13. Sphingosine 1-phosphate induces differentiation of mesoangioblasts towards smooth muscle. A role for GATA6.

    Directory of Open Access Journals (Sweden)

    Chiara Donati

    Full Text Available Different cells can contribute to repair following vascular injury by differentiating into smooth muscle (SM cells; however the extracellular signals involved are presently poorly characterized. Mesoangioblasts are progenitor cells capable of differentiating into various mesoderm cell types including SM cells. In this study the biological action exerted by the pleiotropic sphingolipid sphingosine 1-phosphate (S1P in human mesoangioblasts has been initially investigated by cDNA microarray analysis. Obtained data confirmed the anti-apoptotic action of this sphingolipid and identified for the first time a strong differentiating action toward SM cells. Quantitative mRNA and protein analysis corroborated the microarray results demonstrating enhanced expression of myogenic marker proteins and regulation of the expression of transcription factor GATA6 and its co-regulator, LMCD1. Importantly, GATA6 up-regulation induced by S1P was responsible for the enhanced expression of SM-specific contractile proteins. Moreover, by specific gene silencing experiments GATA6 was critical in the pro-differentiating activity of the cytokine TGFβ. Finally, the pharmacological inhibition of endogenous S1P formation in response to TGFβ abrogated GATA6 up-regulation, supporting the view that the S1P pathway plays a physiological role in mediating the pro-myogenic effect of TGFβ. This study individuates GATA6 as novel player in the complex transcriptional regulation of mesoangioblast differentiation into SM cells and highlights a role for S1P to favour vascular regeneration.

  14. Forces exerted by a correlated fluid on embedded inclusions.

    Science.gov (United States)

    Bitbol, Anne-Florence; Fournier, Jean-Baptiste

    2011-06-01

    We investigate the forces exerted on embedded inclusions by a fluid medium with long-range correlations, described by an effective scalar field theory. Such forces are the basis for the medium-mediated Casimir-like force. To study these forces beyond thermal average, it is necessary to define them in each microstate of the medium. Two different definitions of these forces are currently used in the literature. We study the assumptions underlying them. We show that only the definition that uses the stress tensor of the medium gives the sought-after force exerted by the medium on an embedded inclusion. If a second inclusion is embedded in the medium, the thermal average of this force gives the usual Casimir-like force between the two inclusions. The other definition can be used in the different physical case of an object that interacts with the medium without being embedded in it. We show in a simple example that the two definitions yield different results for the variance of the Casimir-like force.

  15. Chronic Exertional Compartment Syndrome in a Healthy Young Man.

    Science.gov (United States)

    Joubert, Sonia V; Duarte, Manuel A

    2016-06-01

    The purpose of this case report is to describe a patient who presented with symptoms of exercise-induced compartment syndrome and was later referred for bilateral fasciotomy surgery. A 21-year-old patient presented for chiropractic care with the inability to run due to foot paresthesia and weakness. An exertion test and compartment pressure test diagnosed exercise-induced compartment syndrome. Exertion test and compartment pressure test were used to identify and diagnose exercise-induced compartment syndrome. The patient was diagnosed with exercise-induced compartment syndrome. He was treated conservatively and referred for additional testing. The orthopedic surgeon requested that 12 weeks of conservative care be provided prior to testing; treatment consisted of chiropractic care and rehabilitation exercises. Following the 12 weeks of treatment, the patient did not significantly respond to conservative care. A compartment pressure test confirmed the initial diagnosis of exercise-induced compartment syndrome. The patient underwent a unilateral fasciotomy surgery and recovered fully. Following the surgery, the patient returned to the chiropractic clinic with the same presentation in the contralateral leg. The same protocol of management resulted in the same outcome. Two years after surgical intervention, the patient continues to maintain an active lifestyle, able to run 2 to 3 miles per day without any exacerbations or symptomatology. Clinical awareness, a detailed history, and thorough examination with reproduction of symptomatology are necessary to form a proper diagnosis and treatment plan for these patients. Therefore, multidisciplinary medical communication would prove to be the most beneficial approach for the patient.

  16. Chronic Fatigue Syndrome versus Systemic Exertion Intolerance Disease.

    Science.gov (United States)

    Jason, Leonard A; Sunnquist, Madison; Brown, Abigail; Newton, Julia L; Strand, Elin Bolle; Vernon, Suzanne D

    2015-07-01

    The Institute of Medicine has recommended a change in the name and criteria for Chronic Fatigue Syndrome (CFS), renaming the illness Systemic Exertion Intolerance Disease (SEID). The new SEID case definition requires substantial reductions or impairments in the ability to engage in pre-illness activities, unrefreshing sleep, post-exertional malaise, and either cognitive impairment or orthostatic intolerance. In the current study, samples were generated through several different methods and were used to compare this new case definition to previous case definitions for CFS, Myalgic Encephalomyelitis (ME-ICC), Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), as well as a case definition developed through empirical methods. We used a cross-sectional design with samples from tertiary care settings, a biobank sample, and other forums. 796 patients from the US, Great Britain, and Norway completed the DePaul Symptom Questionnaire. Findings indicated that the SEID criteria identified 88% of participants in the samples analyzed, which is comparable to the 92% that met the Fukuda criteria. The SEID case definition was compared to a four item empiric criteria, and findings indicated that the four item empiric criteria identified a smaller, more functionally limited and symptomatic group of patients. The recently developed SEID criteria appears to identify a group comparable in size to the Fukuda et al. criteria, but a larger group of patients than the Canadian ME/CFS and ME criteria, and selects more patients who have less impairment and fewer symptoms than a four item empiric criteria.

  17. Cooling methods used in the treatment of exertional heat illness.

    Science.gov (United States)

    Smith, J E

    2005-08-01

    To review the different methods of reducing body core temperature in patients with exertional heatstroke. The search strategy included articles from 1966 to July 2003 using the databases Medline and Premedline, Embase, Evidence Based Medicine (EBM) reviews, SPORTDiscus, and cross referencing the bibliographies of relevant papers. Studies were included if they contained original data on cooling times or cooling rates in patients with heat illness or normal subjects who were subjected to heat stress. In total, 17 papers were included in the analysis. From the evidence currently available, the most effective method of reducing body core temperature appears to be immersion in iced water, although the practicalities of this treatment may limit its use. Other methods include both evaporative and invasive techniques, and the use of chemical agents such as dantrolene. The main predictor of outcome in exertional heatstroke is the duration and degree of hyperthermia. Where possible, patients should be cooled using iced water immersion, but, if this is not possible, a combination of other techniques may be used to facilitate rapid cooling. There is no evidence to support the use of dantrolene in these patients. Further work should include a randomised trial comparing immersion and evaporative therapy in heatstroke patients.

  18. American football and fatal exertional heat stroke: a case study of Korey Stringer

    Science.gov (United States)

    Grundstein, Andrew; Knox, John A.; Vanos, Jennifer; Cooper, Earl R.; Casa, Douglas J.

    2017-08-01

    On August 1, 2001, Korey Stringer, a Pro Bowl offensive tackle for the Minnesota Vikings, became the first and to date the only professional American football player to die from exertional heat stroke (EHS). The death helped raise awareness of the dangers of exertional heat illnesses in athletes and prompted the development of heat safety policies at the professional, collegiate, and interscholastic levels. Despite the public awareness of this death, no published study has examined in detail the circumstances surrounding Stringer's fatal EHS. Using the well-documented details of the case, our study shows that Stringer's fatal EHS was the result of a combination of physiological limitations, organizational and treatment failings, and extreme environmental conditions. The COMfort FormulA (COMFA) energy budget model was used to assess the relative importance of several extrinsic factors on Stringer's EHS, including weather conditions, clothing insulation, and activity levels. We found that Stringer's high-intensity training in relation to the oppressive environmental conditions was the most prominent factor in producing dangerous, uncompensable heat stress conditions and that the full football uniform played a smaller role in influencing Stringer's energy budget. The extreme energy budget levels that led to the fatal EHS would have been avoided according to our modeling through a combination of reduced intensity and lower clothing insulation. Finally, a long delay in providing medical treatment made the EHS fatal. These results highlight the importance of modern heat safety guidelines that provide controls on extrinsic factors, such as the adjustment of duration and intensity of training along with protective equipment modifications based on environmental conditions and the presence of an emergency action plan focused on rapid recognition and immediate on-site aggressive cooling of EHS cases.

  19. American football and fatal exertional heat stroke: a case study of Korey Stringer.

    Science.gov (United States)

    Grundstein, Andrew; Knox, John A; Vanos, Jennifer; Cooper, Earl R; Casa, Douglas J

    2017-03-17

    On August 1, 2001, Korey Stringer, a Pro Bowl offensive tackle for the Minnesota Vikings, became the first and to date the only professional American football player to die from exertional heat stroke (EHS). The death helped raise awareness of the dangers of exertional heat illnesses in athletes and prompted the development of heat safety policies at the professional, collegiate, and interscholastic levels. Despite the public awareness of this death, no published study has examined in detail the circumstances surrounding Stringer's fatal EHS. Using the well-documented details of the case, our study shows that Stringer's fatal EHS was the result of a combination of physiological limitations, organizational and treatment failings, and extreme environmental conditions. The COMfort FormulA (COMFA) energy budget model was used to assess the relative importance of several extrinsic factors on Stringer's EHS, including weather conditions, clothing insulation, and activity levels. We found that Stringer's high-intensity training in relation to the oppressive environmental conditions was the most prominent factor in producing dangerous, uncompensable heat stress conditions and that the full football uniform played a smaller role in influencing Stringer's energy budget. The extreme energy budget levels that led to the fatal EHS would have been avoided according to our modeling through a combination of reduced intensity and lower clothing insulation. Finally, a long delay in providing medical treatment made the EHS fatal. These results highlight the importance of modern heat safety guidelines that provide controls on extrinsic factors, such as the adjustment of duration and intensity of training along with protective equipment modifications based on environmental conditions and the presence of an emergency action plan focused on rapid recognition and immediate on-site aggressive cooling of EHS cases.

  20. Effects of partial sleep restriction and subsequent daytime napping on prolonged exertional heat strain.

    Science.gov (United States)

    Tokizawa, Ken; Sawada, Shin-Ichi; Tai, Tetsuo; Lu, Jian; Oka, Tatsuo; Yasuda, Akinori; Takahashi, Masaya

    2015-07-01

    It is considered that sleep restriction is one of the risk factors for the development of exertional heat stroke and illness. However, how sleep restriction affects exertional heat strain and the nature of the coping strategy involved in this phenomenon remain unclear. Fourteen healthy subjects were studied on four occasions: after a night of normal sleep (NS, 7-8 h) and after a night of partial sleep restriction (PSR, 4 h), each with or without taking a daytime nap during the subsequent experimental day. The laboratory test consisted of two 40 min periods of moderate walking in a hot room in the morning and the afternoon. The increase in rectal temperature during walking was significantly greater in PSR than in NS in the afternoon. The rating scores for physical and psychological fatigue and sleepiness were significantly greater in PSR than in NS, both in the morning and in the afternoon. The reaction times and lapses in the psychomotor vigilance task (PVT) after walking were significantly worse in PSR than in NS in the morning and after lunch. The nap intervention attenuated significantly the scores for fatigue and sleepiness in PSR. Furthermore, the decreased PVT response in PSR was significantly reversed by the nap. These results suggest that PSR augments physiological and psychological strain and reduces vigilance in the heat. Taking a nap seemed to be effective in reducing psychological strain and inhibiting the decrease in vigilance. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  1. The role of echocardiography in the differential diagnosis between training induced myocardial hypertrophy versus cardiomyopathy.

    Science.gov (United States)

    Venckunas, Tomas; Mazutaitiene, Birute

    2007-01-01

    Increased myocardial mass due to regular high-volume intense exercise training (so-called athlete's heart) is not uncommon. Although directly correlated with the extent of training loads, myocardial hypertrophy is not present exclusively in well-trained or elite athletes. Athlete's heart is considered a physiological phenomenon with no known harmful consequences. However, extreme forms of myocardial hypertrophy due to endurance training resemble a structural heart disease such as hypertrophic cardiomyopathy, a condition associated with substantially increased risk of cardiac event. Endurance sports such as rowing and road cycling, rather than strength/power training, are most commonly associated with left ventricular (LV) wall thickness compatible with hypertrophic cardiomyopathy. The differentiation between physiological and maladaptive cardiac hypertrophy in athletes is undoubtedly important, since untreated cardiac abnormality often possesses a real threat of premature death due to heart failure during intense physical exertion. Luckily, the distinction from pathological hypertrophy is usually straightforward using transthoracic echocardiography, as endurance athletes, in addition to moderately and proportionally thickened LV walls with normal acoustic density, tend to possess increased LV diameter. In more uncertain cases, a detailed evaluation of myocardial function using (tissue) Doppler and contrast echocardiography is effective. When a doubt still remains, knowledge of an athlete's working capacity may be useful in evaluating whether the insidious cardiac pathology is absent. In such cases cardiopulmonary exercise testing typically resolves the dilemma: indices of aerobic capacity are markedly higher in healthy endurance athletes compared to patients. Other characteristics such as a decrease of LV mass due to training cessation are also discussed in the article. Key pointsTransthoracic echocardiography is still the most common relevant differentiation

  2. Perceived Exertion and Metabolic Cost during Progressive and ...

    African Journals Online (AJOL)

    The objective of the study was to ascertain whether selected physiological responses and the perception of effort varied during four different walk protocols where speed increased progressively 3, 4, 5, 6, and 7 km.hr-1 (progressive treadmill walk (PTW); and progressive land walk (PLW); or where the participant adjusted to ...

  3. Physiological acclimation of Lessonia spicata to diurnal changing PAR and UV radiation: differential regulation among down-regulation of photochemistry, ROS scavenging activity and phlorotannins as major photoprotective mechanisms.

    Science.gov (United States)

    Cruces, Edgardo; Rautenberger, Ralf; Rojas-Lillo, Yesenia; Cubillos, Victor Mauricio; Arancibia-Miranda, Nicolás; Ramírez-Kushel, Eduardo; Gómez, Iván

    2017-02-01

    Intertidal macroalgae are constantly subjected to high variations in the quality and quantity of incident irradiance that can eventually generate detrimental effect on the photosynthetic apparatus. The success of these organisms to colonize the stressful coastal habitat is mainly associated with the complexity of their morphological structures and the efficiency of the anti-stress mechanisms to minimize the physiological stress. Lessonia spicata (Phaeophyceae), a brown macroalga, that inhabits the intertidal zone in central-southern Chile was studied in regard to their physiological (quantum yield, electron transport rate, pigments) and biochemical (phlorotannins content, antioxidant metabolism, oxidative stress) responses during a daily light cycle under natural solar radiation. Major findings were that F v/F m, photosynthetic parameters (ETRmax, alpha, E k) and pigments in L. spicata showed an inverse relationship to the diurnal changes in solar radiation. Phlorotannins levels and antioxidant activity showed their highest values in treatment that included UV radiation. There was an increase in SOD and APX in relation at light stress, with a peak in activity between 5.2 and 10.1 W m(-2) of biologically effective dose. The increase in peroxidative damage was proportional to light dose. These results indicated that different light doses can trigger a series of complementary mechanisms of acclimation in L. spicata based on: (i) down-regulation of photochemistry activity and decrease in concentration of photosynthetic pigments; (ii) induction of phenolic compounds with specific UV-screening functions; and (iii) reactive oxygen species (ROS) scavenging activity via complementary repair of the oxidative damage through increased activity of antioxidant enzymes and potentially increased amounts of phenolic compounds.

  4. Optimum polygenic profile to resist exertional rhabdomyolysis during a marathon.

    Directory of Open Access Journals (Sweden)

    Juan Del Coso

    Full Text Available Exertional rhabdomyolysis can occur in individuals performing various types of exercise but it is unclear why some individuals develop this condition while others do not. Previous investigations have determined the role of several single nucleotide polymorphisms (SNPs to explain inter-individual variability of serum creatine kinase (CK concentrations after exertional muscle damage. However, there has been no research about the interrelationship among these SNPs. The purpose of this investigation was to analyze seven SNPs that are candidates for explaining individual variations of CK response after a marathon competition (ACE = 287bp Ins/Del, ACTN3 = p.R577X, CKMM = NcoI, IGF2 = C13790G, IL6 = 174G>C, MLCK = C37885A, TNFα = 308G>A.Using Williams and Folland's model, we determined the total genotype score from the accumulated combination of these seven SNPs for marathoners with a low CK response (n = 36; serum CK <400 U·L-1 vs. marathoners with a high CK response (n = 31; serum CK ≥400 U·L-1.At the end of the race, low CK responders had lower serum CK (290±65 vs. 733±405 U·L-1; P<0.01 and myoglobin concentrations (443±328 vs. 1009±971 ng·mL-1, P<0.01 than high CK responders. Although the groups were similar in age, anthropometric characteristics, running experience and training habits, total genotype score was higher in low CK responders than in high CK responders (5.2±1.4 vs. 4.4±1.7 point, P = 0.02.Marathoners with a lower CK response after the race had a more favorable polygenic profile than runners with high serum CK concentrations. This might suggest a significant role of genetic polymorphisms in the levels of exertional muscle damage and rhabdomyolysis. Yet other SNPs, in addition to exercise training, might also play a role in the values of CK after damaging exercise.

  5. Activation of Neuropeptide Y Receptors Modulates Retinal Ganglion Cell Physiology and Exerts Neuroprotective Actions In Vitro

    DEFF Research Database (Denmark)

    Martins, João; Elvas, Filipe; Brudzewsky, Dan

    2015-01-01

    agonist, increased the initial burst response of OFF-type RGCs, although no effect was observed on RGC spontaneous spiking activity. The Y1 receptor activation was also able to directly modulate RGC responses by attenuating the NMDA-induced increase in RGC spiking activity. These results suggest that Y1...

  6. Spinal cord stimulation exerts neuroprotective effects against experimental Parkinson's disease.

    Directory of Open Access Journals (Sweden)

    Aiko Shinko

    Full Text Available In clinical practice, deep brain stimulation (DBS is effective for treatment of motor symptoms in Parkinson's disease (PD. However, the mechanisms have not been understood completely. There are some reports that electrical stimulation exerts neuroprotective effects on the central nervous system diseases including cerebral ischemia, head trauma, epilepsy and PD, although there are a few reports on neuroprotective effects of spinal cord stimulation (SCS. We investigated the neuroprotective effects of high cervical SCS on PD model of rats. Adult female Sprague-Dawley rats received hour-long SCS (2, 50 or 200 Hz with an epidural electrode at C1-2 level for 16 consecutive days. At 2 days after initial SCS, 6-hydroxydopamine (6-OHDA was injected into the right striatum of rats. Behavioral evaluations of PD symptoms were employed, including cylinder test and amphetamine-induced rotation test performed at 1 and 2 weeks after 6-OHDA injection. Animals were subsequently euthanized for immunohistochemical investigations. In order to explore neurotrophic and growth factor upregulation induced by SCS, another cohort of rats that received 50 Hz SCS was euthanized at 1 and 2 weeks after lesion for protein assays. Behavioral tests revealed that the number of amphetamine-induced rotations decreased in SCS groups. Immunohistochemically, tyrosine hydroxylase (TH-positive fibers in the striatum were significantly preserved in SCS groups. TH-positive neurons in the substantia nigra pars compacta were significantly preserved in 50 Hz SCS group. The level of vascular endothelial growth factor (VEGF was upregulated by SCS at 1 week after the lesion. These results suggest that high cervical SCS exerts neuroprotection in PD model of rats, at least partially by upregulation of VEGF. SCS is supposed to suppress or delay PD progression and might become a less invasive option for PD patients, although further preclinical and clinical investigations are needed to confirm the

  7. Phun Week: Understanding Physiology

    Science.gov (United States)

    Limson, Mel; Matyas, Marsha Lakes

    2009-01-01

    Topics such as sports, exercise, health, and nutrition can make the science of physiology relevant and engaging for students. In addition, many lessons on these topics, such as those on the cardiovascular, respiratory, and digestive systems, align with national and state life science education standards. Physiology Understanding Week (PhUn…

  8. Advances in physiological computing

    CERN Document Server

    Fairclough, Stephen H

    2014-01-01

    This edited collection will provide an overview of the field of physiological computing, i.e. the use of physiological signals as input for computer control. It will cover a breadth of current research, from brain-computer interfaces to telemedicine.

  9. Physiology in conservation translocations

    Science.gov (United States)

    Tarszisz, Esther; Dickman, Christopher R.; Munn, Adam J.

    2014-01-01

    Conservation translocations aim to restore species to their indigenous ranges, protect populations from threats and/or reinstate ecosystem functions. They are particularly important for the conservation and management of rare and threatened species. Despite tremendous efforts and advancement in recent years, animal conservation translocations generally have variable success, and the reasons for this are often uncertain. We suggest that when little is known about the physiology and wellbeing of individuals either before or after release, it will be difficult to determine their likelihood of survival, and this could limit advancements in the science of translocations for conservation. In this regard, we argue that physiology offers novel approaches that could substantially improve translocations and associated practices. As a discipline, it is apparent that physiology may be undervalued, perhaps because of the invasive nature of some physiological measurement techniques (e.g. sampling body fluids, surgical implantation). We examined 232 publications that dealt with translocations of terrestrial vertebrates and aquatic mammals and, defining ‘success’ as high or low, determined how many of these studies explicitly incorporated physiological aspects into their protocols and monitoring. From this review, it is apparent that physiological evaluation before and after animal releases could progress and improve translocation/reintroduction successes. We propose a suite of physiological measures, in addition to animal health indices, for assisting conservation translocations over the short term and also for longer term post-release monitoring. Perhaps most importantly, we argue that the incorporation of physiological assessments of animals at all stages of translocation can have important welfare implications by helping to reduce the total number of animals used. Physiological indicators can also help to refine conservation translocation methods. These approaches fall

  10. Fluoxetine exerts age-dependent effects on behavior and amygdala neuroplasticity in the rat.

    Directory of Open Access Journals (Sweden)

    Judith R Homberg

    Full Text Available The selective serotonin reuptake inhibitor (SSRI Prozac® (fluoxetine is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and thereby may have harmful effects in adolescents. Here we treated adolescent and adult rats chronically with fluoxetine (12 mg/kg at postnatal day (PND 25 to 46 and from PND 67 to 88, respectively, and tested the animals 7-14 days after the last injection when (norfluoxetine in blood plasma had been washed out, as determined by HPLC. Plasma (norfluoxetine levels were also measured 5 hrs after the last fluoxetine injection, and matched clinical levels. Adolescent rats displayed increased behavioral despair in the forced swim test, which was not seen in adult fluoxetine treated rats. In addition, beneficial effects of fluoxetine on wakefulness as measured by electroencephalography in adults was not seen in adolescent rats, and age-dependent effects on the acoustic startle response and prepulse inhibition were observed. On the other hand, adolescent rats showed resilience to the anorexic effects of fluoxetine. Exploratory behavior in the open field test was not affected by fluoxetine treatment, but anxiety levels in the elevated plus maze test were increased in both adolescent and adult fluoxetine treated rats. Finally, in the amygdala, but not the dorsal raphe nucleus and medial prefrontal cortex, the number of PSA-NCAM (marker for synaptic remodeling immunoreactive neurons was increased in adolescent rats, and decreased in adult rats, as a consequence of chronic fluoxetine treatment. No fluoxetine-induced changes in 5-HT(1A receptor immunoreactivity were observed. In conclusion, we show that fluoxetine exerts both harmful and beneficial age-dependent effects on depressive behavior, body weight and wakefulness, which may relate, in part, to differential

  11. Fluoxetine Exerts Age-Dependent Effects on Behavior and Amygdala Neuroplasticity in the Rat

    Science.gov (United States)

    Homberg, Judith R.; Olivier, Jocelien D. A.; Blom, Tom; Arentsen, Tim; van Brunschot, Chantal; Schipper, Pieter; Korte-Bouws, Gerdien; van Luijtelaar, Gilles; Reneman, Liesbeth

    2011-01-01

    The selective serotonin reuptake inhibitor (SSRI) Prozac® (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and thereby may have harmful effects in adolescents. Here we treated adolescent and adult rats chronically with fluoxetine (12 mg/kg) at postnatal day (PND) 25 to 46 and from PND 67 to 88, respectively, and tested the animals 7–14 days after the last injection when (nor)fluoxetine in blood plasma had been washed out, as determined by HPLC. Plasma (nor)fluoxetine levels were also measured 5 hrs after the last fluoxetine injection, and matched clinical levels. Adolescent rats displayed increased behavioral despair in the forced swim test, which was not seen in adult fluoxetine treated rats. In addition, beneficial effects of fluoxetine on wakefulness as measured by electroencephalography in adults was not seen in adolescent rats, and age-dependent effects on the acoustic startle response and prepulse inhibition were observed. On the other hand, adolescent rats showed resilience to the anorexic effects of fluoxetine. Exploratory behavior in the open field test was not affected by fluoxetine treatment, but anxiety levels in the elevated plus maze test were increased in both adolescent and adult fluoxetine treated rats. Finally, in the amygdala, but not the dorsal raphe nucleus and medial prefrontal cortex, the number of PSA-NCAM (marker for synaptic remodeling) immunoreactive neurons was increased in adolescent rats, and decreased in adult rats, as a consequence of chronic fluoxetine treatment. No fluoxetine-induced changes in 5-HT1A receptor immunoreactivity were observed. In conclusion, we show that fluoxetine exerts both harmful and beneficial age-dependent effects on depressive behavior, body weight and wakefulness, which may relate, in part, to differential fluoxetine

  12. Fluoxetine exerts age-dependent effects on behavior and amygdala neuroplasticity in the rat.

    Science.gov (United States)

    Homberg, Judith R; Olivier, Jocelien D A; Blom, Tom; Arentsen, Tim; van Brunschot, Chantal; Schipper, Pieter; Korte-Bouws, Gerdien; van Luijtelaar, Gilles; Reneman, Liesbeth

    2011-01-31

    The selective serotonin reuptake inhibitor (SSRI) Prozac® (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and thereby may have harmful effects in adolescents. Here we treated adolescent and adult rats chronically with fluoxetine (12 mg/kg) at postnatal day (PND) 25 to 46 and from PND 67 to 88, respectively, and tested the animals 7-14 days after the last injection when (nor)fluoxetine in blood plasma had been washed out, as determined by HPLC. Plasma (nor)fluoxetine levels were also measured 5 hrs after the last fluoxetine injection, and matched clinical levels. Adolescent rats displayed increased behavioral despair in the forced swim test, which was not seen in adult fluoxetine treated rats. In addition, beneficial effects of fluoxetine on wakefulness as measured by electroencephalography in adults was not seen in adolescent rats, and age-dependent effects on the acoustic startle response and prepulse inhibition were observed. On the other hand, adolescent rats showed resilience to the anorexic effects of fluoxetine. Exploratory behavior in the open field test was not affected by fluoxetine treatment, but anxiety levels in the elevated plus maze test were increased in both adolescent and adult fluoxetine treated rats. Finally, in the amygdala, but not the dorsal raphe nucleus and medial prefrontal cortex, the number of PSA-NCAM (marker for synaptic remodeling) immunoreactive neurons was increased in adolescent rats, and decreased in adult rats, as a consequence of chronic fluoxetine treatment. No fluoxetine-induced changes in 5-HT(1A) receptor immunoreactivity were observed. In conclusion, we show that fluoxetine exerts both harmful and beneficial age-dependent effects on depressive behavior, body weight and wakefulness, which may relate, in part, to differential fluoxetine

  13. Resveratrol Exerts Dosage and Duration Dependent Effect on Human Mesenchymal Stem Cell Development

    Science.gov (United States)

    Peltz, Lindsay; Gomez, Jessica; Marquez, Maribel; Alencastro, Frances; Atashpanjeh, Negar; Quang, Tara; Bach, Thuy; Zhao, Yuanxiang

    2012-01-01

    Studies in the past have illuminated the potential benefit of resveratrol as an anticancer (pro-apoptosis) and life-extending (pro-survival) compound. However, these two different effects were observed at different concentration ranges. Studies of resveratrol in a wide range of concentrations on the same cell type are lacking, which is necessary to comprehend its diverse and sometimes contradictory cellular effects. In this study, we examined the effects of resveratrol on cell self-renewal and differentiation of human mesenchymal stem cells (hMSCs), a type of adult stem cells that reside in a number of tissues, at concentrations ranging from 0.1 to 10 µM after both short- and long-term exposure. Our results reveal that at 0.1 µM, resveratrol promotes cell self-renewal by inhibiting cellular senescence, whereas at 5 µM or above, resveratrol inhibits cell self-renewal by increasing senescence rate, cell doubling time and S-phase cell cycle arrest. At 1 µM, its effect on cell self-renewal is minimal but after long-term exposure it exerts an inhibitory effect, accompanied with increased senescence rate. At all concentrations, resveratrol promotes osteogenic differentiation in a dosage dependent manner, which is offset by its inhibitory effect on cell self-renewal at high concentrations. On the contrary, resveratrol suppresses adipogenic differentiation during short-term exposure but promotes this process after long-term exposure. Our study implicates that resveratrol is the most beneficial to stem cell development at 0.1 µM and caution should be taken in applying resveratrol as an anticancer therapeutic agent or nutraceutical supplement due to its dosage dependent effect on hMSCs. PMID:22615926

  14. New physiological activities of myosuppressin, sulfakinin and NVP-like peptide in Zophobas atratus beetle.

    Science.gov (United States)

    Marciniak, Pawel; Kuczer, Mariola; Rosinski, Grzegorz

    2011-08-01

    Three neuropeptides Zopat-MS-2 (pEDVDHVFLRFa), Zopat-SK-1 (pETSDDYGHLRFa) and Zopat-NVPL-4trunc. (GRWGGFA), recently isolated from the neuroendocrine system of the Zophobas atratus beetle, were tested for their myotropic and hyperglycaemic activities in this species. These peptides exerted differentiated dose-dependent and tissue specific physiological effects. Zopat-MS-2 inhibited contractions of the isolated heart, ejaculatory duct, oviduct and hindgut of adult beetles and induced bimodal effects in the heart contractile activity of pupae in vivo. It also increased the haemolymph free sugar level in larvae of this species, apart from myotropic activity. Zopat-SK-1 showed myostimulatory action on the isolated hindgut of the adult beetles, but it decreased contractions of the heart, ejaculatory duct and oviduct. Injections of this peptide at a dose of 2 μg also caused delayed cardioinhibitory effects on the heartbeat of the pupae. Together with the ability to increase free sugar level in the haemolymph of larvae these were new physiological activities of sulfakinins in insects. Zopat-NVPL-4trunc. inhibited the muscle contractions of the two organs: hindgut and ejaculatory duct but it was inactive on the oviduct and the heart of the adult beetles. This peptide also increased free sugar level concentration in the haemolymph of Z. atratus larvae. These physiological actions are the first biological activities discovered for this group of the insect peptides. The present work showed pleiotropic activity of three neuropeptides and indicates that the visceral muscle contractions and the haemolymph sugar homeostasis in Z. atratus are regulated by complex mechanisms.

  15. Lipocalin-2 inhibits osteoclast formation by suppressing the proliferation and differentiation of osteoclast lineage cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun-Ju, E-mail: biohjk@knu.ac.kr [Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Yoon, Hye-Jin [Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Yoon, Kyung-Ae [Department of Orthopedic Surgery, Skeletal Diseases Genome Research Center, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Gwon, Mi-Ri; Jin Seong, Sook [Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Suk, Kyoungho [Department of Pharmacology, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Kim, Shin-Yoon [Department of Orthopedic Surgery, Skeletal Diseases Genome Research Center, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of); Yoon, Young-Ran, E-mail: yry@knu.ac.kr [Department of Molecular Medicine, Cell and Matrix Research Institute, Clinical Trial Center, BK21 Plus KNU Biomedical Convergence Program, School of Medicine, Kyungpook National University, Daegu 700-422 (Korea, Republic of)

    2015-06-10

    Lipocalin-2 (LCN2) is a member of the lipocalin superfamily and plays a critical role in the regulation of various physiological processes, such as inflammation and obesity. In this study, we report that LCN2 negatively modulates the proliferation and differentiation of osteoclast precursors, resulting in impaired osteoclast formation. The overexpression of LCN2 in bone marrow-derived macrophages or the addition of recombinant LCN2 protein inhibits the formation of multinuclear osteoclasts. LCN2 suppresses macrophage colony-stimulating factor (M-CSF)-induced proliferation of osteoclast precursor cells without affecting their apoptotic cell death. Interestingly, LCN2 decreases the expression of the M-CSF receptor, c-Fms, and subsequently blocks its downstream signaling cascades. In addition, LCN2 inhibits RANKL-induced osteoclast differentiation and attenuates the expression of c-Fos and nuclear factor of activated T cells c1 (NFATc1), which are important modulators in osteoclastogenesis. Mechanistically, LCN2 inhibits NF-κB signaling pathways, as demonstrated by the suppression of IκBα phosphorylation, nuclear translocation of p65, and NF-κB transcriptional activity. Thus, LCN2 is an anti-osteoclastogenic molecule that exerts its effects by retarding the proliferation and differentiation of osteoclast lineage cells. - Highlights: • LCN2 expression is regulated during osteoclast development. • LCN2 suppresses M-CSF-mediated osteoclast precursor proliferation. • LCN2 inhibits RANKL-induced osteoclast differentiation.

  16. Carbohydrate ingestion during prolonged high-intensity intermittent exercise: impact on affect and perceived exertion.

    Science.gov (United States)

    Backhouse, S H; Ali, A; Biddle, S J H; Williams, C

    2007-10-01

    This study was designed to determine the effects of ingesting a carbohydrate (CHO) solution on affective states and rating of perceived exertion (RPE) during prolonged intermittent high-intensity exercise. Seventeen male soccer players completed a prolonged intermittent high-intensity exercise protocol for 90 min on two occasions, separated by at least 7 days. Participants consumed either a 6.4% CHO (0.6 g/kg body mass (BM)/h) or an artificially sweetened placebo (PLA) solution immediately before (8 mL/kg BM) and every 15 min (3 mL/kg BM) during exercise in a double-blind, counterbalanced design. Pleasure-displeasure, perceived activation, RPE and plasma glucose concentration was assessed. The results showed that compared with the CHO trial, perceived activation were lower in the placebo trial during the last 30 min of exercise and this was accompanied by lowered plasma glucose concentrations. In the CHO trial, RPE was maintained in the last 30 min of exercise but carried on increasing in the PLA trial. Therefore, CHO ingestion during prolonged high-intensity exercise appears to elicit an enhanced perceived activation profile that may impact upon task persistence and performance. This finding is in addition to the physiological and metabolic benefits of the exogenous energy supply.

  17. Exertional dyspnoea in interstitial lung diseases: the clinical utility of cardiopulmonary exercise testing

    Directory of Open Access Journals (Sweden)

    Matteo Bonini

    2017-02-01

    Full Text Available Interstitial lung diseases (ILDs represent a heterogeneous group of pathologies characterised by alveolar and interstitial damage, pulmonary inflammation (usually associated with fibrosis, decreased lung function and impaired gas exchange, which can be attributed to either a known or an unknown aetiology. Dyspnoea is one of the most common and disabling symptoms in patients with ILD, significantly impacting quality of life. The mechanisms causing dyspnoea are complex and not yet fully understood. However, it is recognised that dyspnoea occurs when there is an imbalance between the central respiratory efferent drive and the response of the respiratory musculature. The respiratory derangement observed in ILD patients at rest is even more evident during exercise. Pathophysiological mechanisms responsible for exertional dyspnoea and reduced exercise tolerance include altered respiratory mechanics, impaired gas exchange, cardiovascular abnormalities and peripheral muscle dysfunction. This review describes the respiratory physiology of ILD, both at rest and during exercise, and aims to provide comprehensive and updated evidence on the clinical utility of the cardiopulmonary exercise test in the assessment and management of these pathological entities. In addition, the role of exercise training and pulmonary rehabilitation programmes in the ILD population is addressed.

  18. Fucoxanthin: A Marine Carotenoid Exerting Anti-Cancer Effects by Affecting Multiple Mechanisms

    Directory of Open Access Journals (Sweden)

    Sangeetha Ravi Kumar

    2013-12-01

    Full Text Available Fucoxanthin is a marine carotenoid exhibiting several health benefits. The anti-cancer effect of fucoxanthin and its deacetylated metabolite, fucoxanthinol, is well documented. In view of its potent anti-carcinogenic activity, the need to understand the underlying mechanisms has gained prominence. Towards achieving this goal, several researchers have carried out studies in various cell lines and in vivo and have deciphered that fucoxanthin exerts its anti-proliferative and cancer preventing influence via different molecules and pathways including the Bcl-2 proteins, MAPK, NFκB, Caspases, GADD45, and several other molecules that are involved in either cell cycle arrest, apoptosis, or metastasis. Thus, in addition to decreasing the frequency of occurrence and growth of tumours, fucoxanthin has a cytotoxic effect on cancer cells. Some studies show that this effect is selective, i.e., fucoxanthin has the capability to target cancer cells only, leaving normal physiological cells unaffected/less affected. Hence, fucoxanthin and its metabolites show great promise as chemotherapeutic agents in cancer.

  19. Differential Mechanisms of Binding of Anti-Sigma Factors Escherichia coli Rsd and Bacteriophage T4 AsiA to E. coli RNA Polymerase Lead to Diverse Physiological Consequences▿

    Science.gov (United States)

    Sharma, Umender K.; Chatterji, Dipankar

    2008-01-01

    Anti-sigma factors Escherichia coli Rsd and bacteriophage T4 AsiA bind to the essential housekeeping sigma factor, σ70, of E. coli. Though both factors are known to interact with the C-terminal region of σ70, the physiological consequences of these interactions are very different. This study was undertaken for the purpose of deciphering the mechanisms by which E. coli Rsd and bacteriophage T4 AsiA inhibit or modulate the activity of E. coli RNA polymerase, which leads to the inhibition of E. coli cell growth to different amounts. It was found that AsiA is the more potent inhibitor of in vivo transcription and thus causes higher inhibition of E. coli cell growth. Measurements of affinity constants by surface plasmon resonance experiments showed that Rsd and AsiA bind to σ70 with similar affinity. Data obtained from in vivo and in vitro binding experiments clearly demonstrated that the major difference between AsiA and Rsd is the ability of AsiA to form a stable ternary complex with RNA polymerase. The binding patterns of AsiA and Rsd with σ70 studied by using the yeast two-hybrid system revealed that region 4 of σ70 is involved in binding to both of these anti-sigma factors; however, Rsd interacts with other regions of σ70 as well. Taken together, these results suggest that the higher inhibition of E. coli growth by AsiA expression is probably due to the ability of the AsiA protein to trap the holoenzyme RNA polymerase rather than its higher binding affinity to σ70. PMID:18359804

  20. Differential mechanisms of binding of anti-sigma factors Escherichia coli Rsd and bacteriophage T4 AsiA to E. coli RNA polymerase lead to diverse physiological consequences.

    Science.gov (United States)

    Sharma, Umender K; Chatterji, Dipankar

    2008-05-01

    Anti-sigma factors Escherichia coli Rsd and bacteriophage T4 AsiA bind to the essential housekeeping sigma factor, sigma(70), of E. coli. Though both factors are known to interact with the C-terminal region of sigma(70), the physiological consequences of these interactions are very different. This study was undertaken for the purpose of deciphering the mechanisms by which E. coli Rsd and bacteriophage T4 AsiA inhibit or modulate the activity of E. coli RNA polymerase, which leads to the inhibition of E. coli cell growth to different amounts. It was found that AsiA is the more potent inhibitor of in vivo transcription and thus causes higher inhibition of E. coli cell growth. Measurements of affinity constants by surface plasmon resonance experiments showed that Rsd and AsiA bind to sigma(70) with similar affinity. Data obtained from in vivo and in vitro binding experiments clearly demonstrated that the major difference between AsiA and Rsd is the ability of AsiA to form a stable ternary complex with RNA polymerase. The binding patterns of AsiA and Rsd with sigma(70) studied by using the yeast two-hybrid system revealed that region 4 of sigma(70) is involved in binding to both of these anti-sigma factors; however, Rsd interacts with other regions of sigma(70) as well. Taken together, these results suggest that the higher inhibition of E. coli growth by AsiA expression is probably due to the ability of the AsiA protein to trap the holoenzyme RNA polymerase rather than its higher binding affinity to sigma(70).

  1. Physiological consequences of selective suppression of synaptic transmission in developing cerebral cortical networks in vitro: differential effects on intrinsically generated bioelectric discharges in a living 'model' system for slow-wave sleep activity.

    Science.gov (United States)

    Corner, Michael A; Baker, Robert E; van Pelt, Jaap

    2008-10-01

    Within the context of an updated thorough review of the literature concerning activity-dependent cerebro-cortical development, a survey is made of recent experiments which utilize spontaneous spike-trains as the dependent variable in rodent neocortex cultures when synaptic transmission is interfered with during early ontogeny. Emphasis is placed on the complexity of homeostatic adaptations to reduced as well as intensified firing. Two kinds of adaptation are distinguished: (i) rapid recovery (within several hours) towards baseline levels despite sustained blockade of excitatory synaptic transmission, and (ii) the generation of essentially normal firing patterns in cultures assayed in control medium following development in the presence of excitatory receptor blockers. The former category of homeostatic responses is strongly dependent on the type of preparation, with isolated organotypic explants showing greatly limited plasticity in comparison with co-cultures of matching contralateral pieces of cortical tissue. In such co-cultures, compensatory excitatory drive manifests itself even when all three known types of ionotropic glutamate receptors are chronically blocked, and is then mediated by (muscarinic) cholinergic mechanisms which normally do not contribute measurably to spontaneous activity. The rapid return of high levels of spontaneous firing during sustained selective glutamatergic receptor blockade appears to protect neuronal cultures treated in this way from becoming hyperexcitable. In particular, quasi-epileptiform paroxysmal bursting upon return to control medium, such as appears in preparations where bioelectric activity has been totally suppressed during network formation, fails to appear in chronically receptor blocked cultures. On the contrary, desensitization of blocked glutamate receptors, as a physiological compensation for the up-regulation of non-blocked receptors, could be demonstrated for both the AMPA and the NMDA glutamate receptor sub

  2. Clinical bystander effect exerted by allergen immunotherapy: a hypothesis.

    Science.gov (United States)

    Ciprandi, G

    2015-03-01

    Allergen Immunotherapy (AIT) is able to restore a physiological Th1 response and Tregs function. This effect is allergen-specific, even though it has been reported that it may also be non-specific, such as also extended to allergens not used in AIT. This immunological phenomenon may also be of clinical nature. This case report shows that a poly-allergic patient, successfully treated with Parietaria extract, also achieved a clinical tolerance towards other causal allergens, such as mites and cat. Of course, this was an anecdote, but it is reasonable to prospect the hypothesis that a bystander clinical effect may be observed during AIT in poly-allergic patients.

  3. Matrix Metalloproteinase 9 Exerts Antiviral Activity against Respiratory Syncytial Virus.

    Directory of Open Access Journals (Sweden)

    Abdoulaye J Dabo

    Full Text Available Increased lung levels of matrix metalloproteinase 9 (MMP9 are frequently observed during respiratory syncytial virus (RSV infection and elevated MMP9 concentrations are associated with severe disease. However little is known of the functional role of MMP9 during lung infection with RSV. To determine whether MMP9 exerted direct antiviral potential, active MMP9 was incubated with RSV, which showed that MMP9 directly prevented RSV infectivity to airway epithelial cells. Using knockout mice the effect of the loss of Mmp9 expression was examined during RSV infection to demonstrate MMP9's role in viral clearance and disease progression. Seven days following RSV infection, Mmp9-/- mice displayed substantial weight loss, increased RSV-induced airway hyperresponsiveness (AHR and reduced clearance of RSV from the lungs compared to wild type mice. Although total bronchoalveolar lavage fluid (BALF cell counts were similar in both groups, neutrophil recruitment to the lungs during RSV infection was significantly reduced in Mmp9-/- mice. Reduced neutrophil recruitment coincided with diminished RANTES, IL-1β, SCF, G-CSF expression and p38 phosphorylation. Induction of p38 signaling was required for RANTES and G-CSF expression during RSV infection in airway epithelial cells. Therefore, MMP9 in RSV lung infection significantly enhances neutrophil recruitment, cytokine production and viral clearance while reducing AHR.

  4. Multiple Mechanisms of Anti-Cancer Effects Exerted by Astaxanthin

    Directory of Open Access Journals (Sweden)

    Li Zhang

    2015-07-01

    Full Text Available Astaxanthin (ATX is a xanthophyll carotenoid which has been approved by the United States Food and Drug Administration (USFDA as food colorant in animal and fish feed. It is widely found in algae and aquatic animals and has powerful anti-oxidative activity. Previous studies have revealed that ATX, with its anti-oxidative property, is beneficial as a therapeutic agent for various diseases without any side effects or toxicity. In addition, ATX also shows preclinical anti-tumor efficacy both in vivo and in vitro in various cancer models. Several researches have deciphered that ATX exerts its anti-proliferative, anti-apoptosis and anti-invasion influence via different molecules and pathways including signal transducer and activator of transcription 3 (STAT3, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB and peroxisome proliferator-activated receptor gamma (PPARγ. Hence, ATX shows great promise as chemotherapeutic agents in cancer. Here, we review the rapidly advancing field of ATX in cancer therapy as well as some molecular targets of ATX.

  5. Return to activity following fasciotomy for chronic exertional compartment syndrome.

    Science.gov (United States)

    Irion, Val; Magnussen, Robert A; Miller, Timothy L; Kaeding, Christopher C

    2014-10-01

    Diagnosis of chronic exertional compartment syndrome (CECS) is relatively rare but has been well documented in athletes. There are, however, few reports regarding return to athletic activity after surgery among elite-level athletes. We hypothesized that a majority of elite-level athletes would successfully return to their previous level of competition following fasciotomy for CECS. A retrospective chart review was performed to identify elite-level athletes (collegiate or professional sport participation) who underwent fasciotomy for CECS over a 3-year period. Data collected included sport or activity, treatment and surgical details, time away from sport/activity after surgery, and ability to return to prior level of activity. Six males and seven females were included in the analysis. Patient age ranged from 17 to 24 years with a mean of 19.7 years. Six patients underwent unilateral lower extremity compartment release, and seven underwent bilateral lower extremity compartment release. The anterior and lateral compartments alone were released in 11 patients (84.6%). Two patients (15.4%) underwent four-compartment releases. Eleven patients (84.6%) were able to return to their previous elite level of sport participation at a mean of 10.6 weeks following surgical fasciotomy. Patients who had four-compartment release had a more than 3.5 week average longer return to full sporting activities (p = 0.011). Fasciotomy is effective in allowing elite athletes with CECS to return to sport.

  6. Petiveria alliacea exerts mnemonic and learning effects on rats.

    Science.gov (United States)

    Silva, Mallone Lopes; Luz, Diandra Araújo; Paixão, Thiago Portal da; Silva, João Paulo Bastos; Belém-Filho, Ivaldo Jesus Almeida; Fernandes, Luanna Melo Pereira; Gonçalves, Ana Cristina Baetas; Fontes-Júnior, Enéas Andrade; de Andrade, Marciene Ataíde; Maia, Cristiane Socorro Ferraz

    2015-07-01

    Petiveria alliacea L. (Phytolaccaceae) is a perennial shrub native to the Amazon region and other tropical areas such as Central America and the Caribbean. Popularly known as mucuracaá, P. alliacea is used in the folk medicine for a broad variety of therapeutic purpose and also in religious ceremonies by slaves as a sedative, which highlights its properties on the Central Nervous System (CNS). The present study evaluated the effects of the P. alliacea leaves hydroalcoholic extract (PaLHE) on the cognition, including learning and memory. Three-month-old male and female Wistar rats (n=8-10/group) were administered with 900mg/kg of PaLHE. The behavioral assays included Step-down Inhibitory avoidance (IA) and Morris Water Maze (MWM) tests. Consistent with our previous reports, P. alliacea improved long-term memory. It also exerted previously unreported effects on short-term and spatial memory improvement, and increased learning in the tasks. The P. alliacea extract elicited mnemonic effects and improved the learning process in both IA and MWM tests. Our results highlight the importance of further studies in order to identify the active substances of the PaLHE and investigate the pharmacological mechanisms that underlies the reported effects. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Perceived exertion and anaerobic threshold during the menstrual cycle.

    Science.gov (United States)

    Stephenson, L A; Kolka, M A; Wilkerson, J E

    1982-01-01

    Six adult females with normal menstrual cycles (28-31 d in length) volunteered to exercise on a bicycle ergometer on five different days of their menstrual cycles (days 2, 8, 14, 20, and 26; day 1 = onset of menstruation). Each day the subjects exercised at a maximum work load (184.4 W) and at four submaximal exercise intensities (45.0, 83.1, 121.4 and 154.4 W). Ratings of perceived exertion (RPE) were obtained during minute 4 of each 5-min submaximal exercise bout and at exhaustion each day. Overall, RPE was linearly correlated with heart rate (r = 0.87) when all exercise intensities and cycle days were considered. There was no statistically significant (P greater than 0.05) change in RPE at any exercise intensity related to cycle day. Factors (expired ventilatory volume, respiratory frequency, tidal volume, end-tidal CO2 tension, and heart rate) that may have affected RPE, maximal aerobic power, and anaerobic threshold (AT) were also statistically unchanged because of cycle day. Anaerobic threshold averaged 68.7% of the VO2max, or 1.592 l . min for all cycle days, as determined by the total expiratory volume/oxygen uptake "break point" method of Wasserman and co-workers (18). These data support the utilization of female subjects with normal menstrual cycles in psychophysiological studies without regard to menstrual cycle phase.

  8. [Angina-like chest pain and exertional esophageal ph monitoring].

    Science.gov (United States)

    Romand, F; Vincent, E; Potier, V; Claudel, N; Galoo, E; Desbaumes, J

    1999-03-01

    Spontaneous chest pain attacks are uncommon during 24-hour esophageal pH monitoring in patients suffering from angina-like chest pain suspected to be acid-related. The aim of this study was to assess the diagnostic value of exertional esophageal pH monitoring and to prove that exercise testing induces chest pain and gastro-esophageal reflux and therefore improves symptomatic correlation study. Forty three patients suffering from angina-like chest pain underwent treadmill exercise testing during a 24-hour esophageal pH monitoring. Symptom analysis was made using the symptom-association probability described by Weusten. During the 24-hour pH monitoring, 10 patients (23%) had a pathologic esophageal acid exposure, 20 (46%) experienced chest pain and 3 (7%) had a symptom association probability > 95%. During the exercise testing on a treadmill, 19 patients (44%) had gastro-esophageal reflux, and 14 (32%) experienced chest pain, coinciding with a gastro-esophageal reflux in 8 (19%). After exercise testing, the symptom-association probability analysis was significantly changed in 9 patients (21%), > 95% in 6 patients (14%). Exercise testing on a treadmill induces chest pain episodes during a 24-hour esophageal pH monitoring and therefore improves symptomatic correlation study in patients suffering from angina-like chest pain.

  9. Multiple Mechanisms of Anti-Cancer Effects Exerted by Astaxanthin.

    Science.gov (United States)

    Zhang, Li; Wang, Handong

    2015-07-14

    Astaxanthin (ATX) is a xanthophyll carotenoid which has been approved by the United States Food and Drug Administration (USFDA) as food colorant in animal and fish feed. It is widely found in algae and aquatic animals and has powerful anti-oxidative activity. Previous studies have revealed that ATX, with its anti-oxidative property, is beneficial as a therapeutic agent for various diseases without any side effects or toxicity. In addition, ATX also shows preclinical anti-tumor efficacy both in vivo and in vitro in various cancer models. Several researches have deciphered that ATX exerts its anti-proliferative, anti-apoptosis and anti-invasion influence via different molecules and pathways including signal transducer and activator of transcription 3 (STAT3), nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and peroxisome proliferator-activated receptor gamma (PPARγ). Hence, ATX shows great promise as chemotherapeutic agents in cancer. Here, we review the rapidly advancing field of ATX in cancer therapy as well as some molecular targets of ATX.

  10. Association between work engagement and perceived exertion among healthcare workers

    Directory of Open Access Journals (Sweden)

    Rodrigo Luiz Carregaro

    Full Text Available INTRODUCTION: Complaints and musculoskeletal discomforts are common manifestations of individuals affected by work-related disorders (WRMD, and the influence of individual and/or psychosocial risk factors may play a significant role in WRMD development. OBJECTIVE: To evaluate and to compare work engagement (WE and ratings of perceived exertion (RPE and to assess the association between indexes of WE and RPE among healthcare workers. MATERIALS AND METHODS: Seventeen female subjects (36 ± 11 years, 1.58 ± 0.06 m and 59 ± 9 kg participated, all officially employed on a nonprofit agency. The Nordic Questionnaire was used to evaluate musculoskeletal complaints and the Borg Scale used to evaluate the RPE. The Utrecht Work Engagement Scale quantified WE (vigor, dedication and absorption domains. Participants were divided into two groups, according to their sectors: healthcare clinics and institution for the elderly. The independent student t test was used to verify differences between groups and the chi-square test to verify associations between variables. RESULTS: All subjects reported musculoskeletal complaints, mainly in the low back (58%. RPE did not differ between groups, while in the vigor, it was found a significant statistically difference (p = 0.035. An association between RPE and vigor and RPE and dedication was establish (p = 0.02 and p = 0.036, respectively. CONCLUSION: The association between WE and RPE suggests that workers with lower indexes of vigor and dedication may perceive greater physical demand, which can be imposed by work demands.

  11. Reproduction, physiology and biochemistry

    Science.gov (United States)

    This chapter summarizes fundamental knowledge and recent discoveries about the reproduction, physiology and biochemistry of plant-parasitic nematodes. Various types of reproduction are reviewed, including sexual reproduction and mitotic and meiotic parthenogenesis. Although much is known about the p...

  12. The dorsal prefrontal and dorsal anterior cingulate cortices exert complementary network signatures during encoding and retrieval in associative memory.

    Science.gov (United States)

    Woodcock, Eric A; White, Richard; Diwadkar, Vaibhav A

    2015-09-01

    Cognitive control includes processes that facilitate execution of effortful cognitive tasks, including associative memory. Regions implicated in cognitive control during associative memory include the dorsal prefrontal (dPFC) and dorsal anterior cingulate cortex (dACC). Here we investigated the relative degrees of network-related interactions originating in the dPFC and dACC during oscillating phases of associative memory: encoding and cued retrieval. Volunteers completed an established object-location associative memory paradigm during fMRI. Psychophysiological interactions modeled modulatory network interactions from the dPFC and dACC during memory encoding and retrieval. Results were evaluated in second level analyses of variance with seed region and memory process as factors. Each seed exerted differentiable modulatory effects during encoding and retrieval. The dACC exhibited greater modulation (than the dPFC) on the fusiform and parahippocampal gyrus during encoding, while the dPFC exhibited greater modulation (than the dACC) on the fusiform, hippocampus, dPFC and basal ganglia. During retrieval, the dPFC exhibited greater modulation (than the dACC) on the parahippocampal gyrus, hippocampus, superior parietal lobule, and dPFC. The most notable finding was a seed by process interaction indicating that the dACC and the dPFC exerted complementary modulatory control on the hippocampus during each of the associative memory processes. These results provide evidence for differentiable, yet complementary, control-related modulation by the dACC and dPFC, while establishing the primacy of dPFC in exerting network control during both associative memory phases. Our approach and findings are relevant for understanding basic processes in human memory and psychiatric disorders that impact associative memory-related networks. Copyright © 2015. Published by Elsevier B.V.

  13. [Division and specialization of the Western European physiology].

    Science.gov (United States)

    Hwang, S I; Kim, O J

    1992-01-01

    The 19th century has been thought to be the turning point that the experimental method began to take strong root as the core to solve many physiological subjects, and the discipline of physiology got firmly fixed as the specialized one in the western Europe. Authors found the following characteristics in the process of the division and specialization of the 19th century western physiology. 1) It was the process of its separation from the discipline of anatomy that was necessary in the development of physiology as the independent, specialized division. Newly grown ideas, that there were working functions specialized study, were the important background and basis of the development of physiology as the specialized discipline. 2) It was not until the force and influence of the metaphysical concept on the living things (vitalism) grew weak that physiology could become the specialized discipline. The new materialistic concept about living things made it possible for the researchers of that time to apply the physico-chemical method in the study of physiological problems. 3) Institutionalization of the physiological research and education accelerated its development and specialization. The followings appeared in the mid-19th century: specialized professorship, division as the separated subject in the undergraduated medical school curriculum, laboratory settings for the purpose of physiological study, establishment of independent academic societies and publication of their own journals. Two main factors, namely, both the settlement of the new physiological thought and method of the very scientific nature and the institutionalization within the academic and medical societies, exerted influences on each other in the ground of the 19th century western Europe. Through that process, the discipline of physiology took root deep as the independent specialized division in the societies of science and medicine.

  14. Physiology of Ramadan fasting

    OpenAIRE

    Shokoufeh Bonakdaran

    2016-01-01

    Considering the emphasis of Islam on the importance of fasting, Muslims attempt to fast from dawn until sunset during the holy month of Ramadan. Fasting is associated with several benefits for normal and healthy individuals. However, it could pose high risks to the health of diabetic patients due to certain physiological changes. This study aimed to compare the physiological changes associated with fasting in healthy individuals and diabetic patients during Ramadan. Furthermore, we reviewed t...

  15. Respiratory physiology at altitude.

    Science.gov (United States)

    Sandberg, C; Naylor, J

    2011-03-01

    The changes in respiratory physiology that occur with increasing altitude are driven by the fall in the partial pressure of oxygen that occurs with decreasing barometric pressure. At altitude, respiratory system changes occur which impact on each step of the oxygen cascade that occurs within the body. These changes are pivotal to the process of acclimatisation to altitude. The study of human respiratory physiology at altitude has the potential to produce research that will be translational to disease states characterised by hypoxaemia.

  16. Physiological ecology meets climate change.

    Science.gov (United States)

    Bozinovic, Francisco; Pörtner, Hans-Otto

    2015-03-01

    In this article, we pointed out that understanding the physiology of differential climate change effects on organisms is one of the many urgent challenges faced in ecology and evolutionary biology. We explore how physiological ecology can contribute to a holistic view of climate change impacts on organisms and ecosystems and their evolutionary responses. We suggest that theoretical and experimental efforts not only need to improve our understanding of thermal limits to organisms, but also to consider multiple stressors both on land and in the oceans. As an example, we discuss recent efforts to understand the effects of various global change drivers on aquatic ectotherms in the field that led to the development of the concept of oxygen and capacity limited thermal tolerance (OCLTT) as a framework integrating various drivers and linking organisational levels from ecosystem to organism, tissue, cell, and molecules. We suggest seven core objectives of a comprehensive research program comprising the interplay among physiological, ecological, and evolutionary approaches for both aquatic and terrestrial organisms. While studies of individual aspects are already underway in many laboratories worldwide, integration of these findings into conceptual frameworks is needed not only within one organism group such as animals but also across organism domains such as Archaea, Bacteria, and Eukarya. Indeed, development of unifying concepts is relevant for interpreting existing and future findings in a coherent way and for projecting the future ecological and evolutionary effects of climate change on functional biodiversity. We also suggest that OCLTT may in the end and from an evolutionary point of view, be able to explain the limited thermal tolerance of metazoans when compared to other organisms.

  17. Exertional hypoxemia in stable COPD is common and predicted by circulating proadrenomedullin.

    Science.gov (United States)

    Stolz, Daiana; Boersma, Wim; Blasi, Francesco; Louis, Renaud; Milenkovic, Branislava; Kostikas, Kostantinos; Aerts, Joachim G; Rohde, Gernot; Lacoma, Alicia; Rakic, Janko; Boeck, Lucas; Castellotti, Paola; Scherr, Andreas; Marin, Alicia; Hertel, Sabine; Giersdorf, Sven; Torres, Antoni; Welte, Tobias; Tamm, Michael

    2014-08-01

    The prevalence of exertional hypoxemia in unselected patients with COPD is unknown. Intermittent hypoxia leads to adrenomedullin (ADM) upregulation through the hypoxia-inducible factor-1 pathway. We aimed to assess the prevalence and the annual probability to develop exertional hypoxemia in stable COPD. We also hypothesized that increased ADM might be associated with exertional hypoxemia and envisioned that adding ADM to clinical variables might improve its prediction in COPD. A total of 1,233 6-min walk tests and circulating proadrenomedullin (proADM) levels from 574 patients with clinically stable, moderate to very severe COPD enrolled in a multinational cohort study and followed up for 2 years were concomitantly analyzed. The prevalence of exertional hypoxemia was 29.1%. In a matrix derived from a fitted-multistate model, the annual probability to develop exertional hypoxemia was 21.6%. Exertional hypoxemia was associated with greater deterioration of specific domains of health-related quality of life, higher severe exacerbation, and death annual rates. In the logistic linear and conditional Cox regression multivariable analyses, both FEV1% predicted and proADM proved independent predictors of exertional hypoxemia (P 2 nmol/L) presented increased risk (> 30%) for exertional desaturation. Exertional desaturation is common and associated with poorer clinical outcomes in COPD. ADM improves prediction of exertional desaturation as compared with the use of FEV1% predicted alone. ISRCTN Register; No.: ISRCTN99586989; URL: www.controlled-trials.com.

  18. Anatomy and physiology of genital organs - women.

    Science.gov (United States)

    Graziottin, Alessandra; Gambini, Dania

    2015-01-01

    "Anatomy is destiny": Sigmund Freud viewed human anatomy as a necessary, although not a sufficient, condition for understanding the complexity of human sexual function with a solid biologic basis. The aim of the chapter is to describe women's genital anatomy and physiology, focusing on women's sexual function with a clinically oriented vision. Key points include: embryology, stressing that the "female" is the anatomic "default" program, differentiated into "male" only in the presence of androgens at physiologic levels for the gestational age; sex determination and sex differentiation, describing the interplay between anatomic and endocrine factors; the "clitoral-urethral-vaginal" complex, the most recent anatomy reading of the corpora cavernosa pattern in women; the controversial G spot; the role of the pelvic floor muscles in modulating vaginal receptivity and intercourse feelings, with hyperactivity leading to introital dyspareunia and contributing to provoked vestibulodynia and recurrent postcoital cystitis, whilst lesions during delivery reduce vaginal sensations, genital arousability, and orgasm; innervation, vessels, bones, ligaments; and the physiology of women's sexual response. Attention to physiologic aging focuses on "low-grade inflammation," genital and systemic, with its impact on women sexual function, especially after the menopause, if the woman does not or cannot use hormone replacement therapy. © 2015 Elsevier B.V. All rights reserved.

  19. A miniswine model of acute exertional heat exhaustion.

    Science.gov (United States)

    Gentile, B J; Szlyk-Modrow, P C; Durkot, M J; Krestel, B A; Sils, I V; Tartarini, K A; Alkhyyat, A M

    1996-06-01

    We examined the thermoregulatory and hemodynamic responses of 12 miniswine (31 +/- 3.9 kg) during 25-30 min of treadmill exercise (5.4 km.h-1, 5% grade) under cool (10 degrees C), moderate (20 degrees C) and warm (30 degrees C) ambient temperature (Ta) conditions. Within 15-20 min of exercise at Ta = 30 degrees C, the miniswine demonstrated significant hyperventilation, hypersalivation, and unsteady gait. Exercise-heat endurance time (T) at Ta = 30 degrees C decreased by 35% and 40% in comparison to T at Ta = 20 degrees C and 10 degrees C, respectively. This resulted from a significant rise in heat strain (S)-defined as the rate of change in rectal temperature. Averaged throughout exercise, S increased from 0.04 +/- 0.01 degree C.min-1 and 0.05 +/- 0.02 degree C.min-1 at Ta = 10 degrees C and 20 degrees C, respectively, to 0.10 +/- 0.03 degree C.min-1 at Ta = 30 degrees C. Due to the comparatively large storage capacity of the porcine spleen relative to humans, splenectomized miniswine were used. This permitted calculation of percentage changes in plasma volume (% delta PVc) from hematocrit (HCT) and hemoglobin (HGB) without the confounding effects of splenic red cells released into the circulation during exercise. Independent of Ta, pre-exercise PVc decreased 3%-5% (p post-exercise. We conclude that the poor thermoregulatory ability of miniswine manifested in insignificant sweating and restricted evaporative cooling, may make them an appropriate model for acute exertional heat exhaustion in humans working in hot, humid conditions and/or wearing impermeable protective clothing. Further, evaluation of plasma volume changes from HCT and HGB in a miniswine model should consider the merit of a splenectomized design.

  20. Relationship between perceived exertion during exercise and subsequent recovery measurements

    Directory of Open Access Journals (Sweden)

    TN Mann

    2016-12-01

    Full Text Available The return towards resting homeostasis in the post-exercise period has the potential to represent the internal training load of the preceding exercise bout. However, the relative potential of metabolic and autonomic recovery measurements in this role has not previously been established. Therefore the aim of this study was to investigate which of 4 recovery measurements was most closely associated with Borg’s Rating of Perceived Exertion (RPE, a measurement widely acknowledged as an integrated measurement of the homeostatic stress of an exercise bout. A heterogeneous group of trained and untrained participants (n = 36 completed a bout of exercise on the treadmill (3 km at 70% of maximal oxygen uptake followed by 1 hour of controlled recovery. Expired respiratory gases and heart rate (HR were measured throughout the exercise and recovery phases of the trial with recovery measurements used to calculate the magnitude of excess post-exercise oxygen consumption (EPOCMAG, the time constant of the EPOC curve (EPOCτ, 1 min heart rate recovery (HRR60s and the time constant of the HR recovery curve (HRRτ for each participant. RPE taken in the last minute of exercise was significantly associated with HRR60s (r=-0.69, EPOCτ (r=0.52 and HRRτ (r=0.43 but not with EPOCMAG. This finding suggests that, of the 4 recovery measurements under investigation, HRR60s shows modest potential to represent inter-individual variation in the homeostatic stress of a standardized exercise bout, in a group with a range of fitness levels.

  1. Isolated Chronic Exertional Compartment Syndrome of the Lateral Lower Leg

    Science.gov (United States)

    van Zantvoort, Aniek P.M.; de Bruijn, Johan A.; Winkes, Michiel B.; Dielemans, Jeanne P.; van der Cruijsen-Raaijmakers, Marike; Hoogeveen, Adwin R.; Scheltinga, Marc R.

    2015-01-01

    Background: Exercise-induced lower leg pain may be caused by chronic exertional compartment syndrome (CECS). The anterior (ant-CECS) or deep posterior compartment (dp-CECS) is usually affected. Knowledge regarding CECS of the lateral compartment (lat-CECS) is limited. Purpose: To describe demographic characteristics and symptoms in a consecutive series of patients with isolated CECS of the lateral compartment of the leg. Study Design: Case series; Level of evidence, 4. Methods: Since 2001, patients undergoing dynamic intracompartmental pressure (ICP) measurements for suspected CECS in a single institution were prospectively monitored. Individuals with a history possibly associated with lat-CECS and elevated ICP measurements (Pedowitz criteria) were identified. Exclusion criteria were concomitant ipsilateral ant-CECS/dp-CECS, acute compartment syndrome, recent significant trauma, peroneal nerve entrapment, or vascular claudication. Results: During an 11-year time period, a total of 26 patients with isolated lat-CECS fulfilled study criteria (15 females; median age, 21 years; range, 14-48 years). Frequently identified provocative sports were running (n = 4), walking (n = 4), field hockey (n = 3), soccer (n = 3), and volleyball (n = 2). Exercise-induced lateral lower leg pain (92%) and tightness (42%) were often reported. The syndrome was bilateral in almost two-thirds (62%, n = 16). Delay in diagnosis averaged 24 months (range, 2 months to 10 years). Conclusion: Young patients with exercise-induced pain in the lateral portions of the lower leg may suffer from isolated CECS of the lateral compartment. ICP measurements in the lateral compartment in these patients are recommended. PMID:26740955

  2. Use of ratings of perceived exertion in sports.

    Science.gov (United States)

    Eston, Roger

    2012-06-01

    The rating of perceived exertion (RPE) is a recognized marker of intensity and of homeostatic disturbance during exercise. It is typically monitored during exercise tests to complement other measures of intensity. The purpose of this commentary is to highlight the remarkable value of RPE as a psychophysiological integrator in adults. It can be used in such diverse fashions as to predict exercise capacity, assess changes in training status, and explain changes in pace and pacing strategy. In addition to using RPE to self-regulate exercise, a novel application of the intensity:RPE relationship is to clamp RPE at various levels to produce self-paced bouts of exercise, which can be used to assess maximal functional capacity. Research also shows that the rate of increase in RPE during self-paced competitive events of varying distance, or constant-load tasks where the participant exercises until volitional exhaustion, is proportional to the duration that remains. These findings suggest that the brain regulates RPE and performance in an anticipatory manner based on awareness of metabolic reserves at the start of an event and certainty of the anticipated end point. Changes in pace may be explained by a continuous internal negotiation of momentary RPE compared with a preplanned "ideal rate of RPE progression" template, which takes into account the portion of distance covered and the anticipated end point. These observations have led to the development of new techniques to analyze the complex relationship of RPE and pacing. The use of techniques to assess frontal-cortex activity will lead to further advances in understanding.

  3. Outcomes of exertional rhabdomyolysis following high-intensity resistance training.

    Science.gov (United States)

    Huynh, A; Leong, K; Jones, N; Crump, N; Russell, D; Anderson, M; Steinfort, D; Johnson, D F

    2016-05-01

    High-intensity resistance training (HIRT) programmes are increasingly popular amongst personal trainers and those attending gymnasiums. We report the experience of exertional rhabdomyolysis (ER) at two tertiary hospitals in Melbourne, Australia. To compare the clinical outcomes of ER with other causes of rhabdomyolysis. Retrospective cross-sectional study of patients presenting with a serum creatine kinase (CK) of greater than 25 000 units/L from 1 September 2013 to 31 August 2014 at two tertiary referral hospitals in Melbourne, Australia. Records were examined to identify care measures implemented during hospital stay, clinical outcomes during admission and on subsequent follow up. Thirty four cases of rhabdomyolysis with a CK of greater than 25 000 units/L (normal range: 20-180 units/L) were identified during the 12-month study period. Twelve of the 34 cases (35%) had ER with 10 of 12 related to HIRT. No acute kidney injury, intensive care admission or death were seen among those with ER. All cases were managed conservatively, with 11 admitted and 9 receiving intravenous fluids only. In contrast, patients with rhabdomyolysis from other causes experienced significantly higher rates of intensive care admission (64%, P = 0.0002), acute kidney injury (82%, P = 0.0001) and death (27%, P = 0.069). ER resulting from HIRT appears to have a benign course compared with rhabdomyolysis of other aetiologies in patients with a serum CK greater than 25 000 units/L. Conservative management of ER appears to be adequate, although this requires confirmation in future prospective studies. © 2016 Royal Australasian College of Physicians.

  4. Effects of caffeine on session ratings of perceived exertion.

    Science.gov (United States)

    Killen, L G; Green, J M; O'Neal, E K; McIntosh, J R; Hornsby, J; Coates, T E

    2013-03-01

    This study examined effects of caffeine on session ratings of perceived exertion (RPE) following 30 min constant-load cycling. Individuals (n = 15) of varying aerobic fitness completed a [Formula: see text] max trial and two 30 min cycling bouts (double-blind, counterbalanced) following ingestion of 6 mL/kg of caffeine or matched placebo. RPE overall, legs and breathing were estimated every 5 min and session RPE was estimated 30 min post-exercise using the OMNI pictorial scale. Session RPE for caffeine and placebo trails were compared using paired t test. Between-trial comparisons of HR, RPE overall, RPE legs and RPE breathing were analyzed using an independent 2 (trial) × 6 (time point) repeated measures analysis of variance (ANOVA) for each dependent variable. Caffeine resulted in a significantly lower session RPE (p < 0.05) for caffeine (6.1 ± 2.2) versus placebo (6.8 ± 2.1). Acute perceptual responses were significantly lower for caffeine for RPE overall (15, 20, 25, and 30 min), RPE breathing (15, 20, 25, and 30 min) and RPE legs (20 and 30 min). Survey responses post-exercise revealed greater feelings of nervousness, tremors, restlessness and stomach distress following caffeine versus placebo. Blunted acute RPE and survey responses suggest participants responded to caffeine ingestion. Caffeine decreased acute RPE during exercise which could partially account for lower session RPE responses. However, decreased session RPE could also reveal a latent analgesic affect of caffeine extending into recovery. Extending the understanding of session RPE could benefit coaches in avoiding overtraining when adjusting training programs.

  5. Physiological, Biochemical, Epigenetic and Molecular Analyses of Wheat (Triticum aestivum Genotypes with Contrasting Salt Tolerance

    Directory of Open Access Journals (Sweden)

    Suresh Kumar

    2017-06-01

    Full Text Available Abiotic stress exerts significant impact on plant’s growth, development, and productivity. Productivity of crop plants under salt stress is lagging behind because of our limited knowledge about physiological, biochemical, epigenetic, and molecular mechanisms of salt tolerance in plants. This study aimed to investigate physio-biochemical, molecular indices and defense responses of selected wheat cultivars to identify the most contrasting salt-responsive genotypes and the mechanisms associated with their differential responses. Physio-biochemical traits specifically membrane stability index, antioxidant potential, osmoprotectants and chlorophyll contents, measured at vegetative stage, were used for multivariate analysis to identify the most contrasting genotypes. Genetic and epigenetic analyses indicated the possible mechanisms associated with differential response of the wheat genotypes under salt stress. Better antioxidant potential, membrane stability, increased accumulation of osmolytes/phytophenolics, and higher K+/Na+ ratio under 200 mM NaCl stress identified Kharchia-65 to be the most salt-tolerant cultivar. By contrast, increased MDA level, reduced soluble sugar, proline, total chlorophyll, total phenolics contents, and lower antioxidant potential in HD-2329 marked it to be sensitive to the stress. Genetic and bioinformatics analyses of HKT1;4 of contrasting genotypes (Kharchia-65 and HD-2329 revealed deletions, transitions, and transversions resulting into altered structure, loss of conserved motifs (Ser-Gly-Gly-Gly and Gly-Arg and function in salt-sensitive (HD-2329 genotype. Expression analysis of HKTs rationalized the observed responses. Epigenetic variations in cytosine methylation explained tissue- and genotype-specific differential expression of HKT2;1 and HKT2;3.

  6. Three-minute constant rate step test for detecting exertional dyspnea relief after bronchodilation in COPD

    Directory of Open Access Journals (Sweden)

    Borel B

    2016-11-01

    Full Text Available Benoit Borel,1,2 Courtney A Wilkinson-Maitland,3 Alan Hamilton,4 Jean Bourbeau,5 Hélène Perrault,6 Dennis Jensen,3,5,7 François Maltais2 1Laboratoire HAVAE, Université de Limoges, Limoges, France; 2Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, 3Clinical Exercise and Respiratory Physiology Laboratory, Department of Kinesiology and Physical Education, McGill University, Montréal, QC, 4Boehringer Ingelheim (Canada Limited, Burlington, ON, 5Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute, McGill University Health Center, Montreal, QC, 6Faculty of Health Sciences, University of Ottawa, Ottawa, ON, 7Translational Research in Respiratory Diseases Program, Research Institute of the McGill University Health Centre, Montreal, QC, Canada Background: The aim of this study was to evaluate the responsiveness of the 3-minute constant rate step test (3-MST to detect the relief of exertional dyspnea (respiratory discomfort after acute bronchodilation in COPD patients. Patients and methods: A total of 40 patients with moderate-to-severe COPD (mean forced expiratory volume in 1 second: 45.7 (±14.7, % predicted performed four 3-MSTs at randomly assigned stepping rates of 14, 16, 20 and 24 steps/min after inhalation of nebulized ipratropium bromide (500 µg/salbutamol (2.5 mg and saline placebo, which were randomized to order. Patients rated their intensity of perceived dyspnea at the end of each 3-MST using Borg 0–10 category ratio scale. Results: A total of 37 (92.5%, 36 (90%, 34 (85% and 27 (67.5% patients completed all 3 minutes of exercise at 14, 16, 20 and 24 steps/min under both treatment conditions, respectively. Compared with placebo, ipratropium bromide/salbutamol significantly decreased dyspnea at the end of the third minute of exercise at 14 steps/min (by 0.6±1.0 Borg 0–10 scale units, P<0.01 and 16 steps/min (by 0.7±1.3 Borg 0–10 scale

  7. Endothelial Cell-derived Extracellular Vesicles Size-dependently Exert Procoagulant Activity Detected by Thromboelastometry.

    Science.gov (United States)

    Holnthoner, Wolfgang; Bonstingl, Cornelia; Hromada, Carina; Muehleder, Severin; Zipperle, Johannes; Stojkovic, Stefan; Redl, Heinz; Wojta, Johann; Schöchl, Herbert; Grillari, Johannes; Weilner, Sylvia; Schlimp, Christoph J

    2017-06-16

    Endothelial cells (ECs) are major modulators of hemostasis by expressing and releasing pro- and anticoagulant mediators into the circulation. Previous studies showed that cultured ECs release procoagulant mediators into cell culture supernatants as evidenced by the reduction of viscoelastic clotting time. This effect was reversed with an anti-tissue factor antibody. Here, we aimed to investigate whether tissue factor (TF) was released by endothelial-derived extracellular vesicles (EVs) and which portion of the released vesicles displays the most prominent procoagulant properties. After stimulation of ECs with tumor-necrosis factor-α (TNF-α) the supernatants of EC cultures were subjected to differential centrifugation steps to collect larger and smaller EVs which were then characterised by nanoparticle tracking analysis (NTA) and flow cytometry. Mixed with fresh human blood and analysed by thromboelastometry EVs exerted a significant procoagulant stimulus, which could be partly reversed by addition of an anti-TF antibody. Moreover, TF activity was confirmed in the centrifuged fractions. In summary, our results provide evidence of the procoagulant potential of smaller and larger endothelial-derived EV fractions detected by thromboelastometry. The observed effect is most likely due to the release of TF-bearing EVs of different dimensions, which are released upon TNF-α stimulation of endothelial cell cultures.

  8. Effects of immune supplementation and immune challenge on oxidative status and physiology in a model bird: implications for ecologists

    NARCIS (Netherlands)

    Crommenacker, van de J.; Horrocks, N.P.C.; Versteegh, M.A.; Tieleman, B.I.; Komdeur, J.; Matson, K.D.

    2010-01-01

    One route to gain insight into the causes and consequences of ecological differentiation is to understand the underlying physiological mechanisms. We explored the relationships between immunological and oxidative status and investigated how birds cope physiologically with the effects of

  9. Effects of immune supplementation and immune challenge on oxidative status and physiology in a model bird : implications for ecologists

    NARCIS (Netherlands)

    van de Crommenacker, Janske; Horrocks, Nicholas P. C.; Versteegh, Maaike A.; Komdeur, Jan; Tieleman, B. Irene; Matson, Kevin D.

    2010-01-01

    One route to gain insight into the causes and consequences of ecological differentiation is to understand the underlying physiological mechanisms. We explored the relationships between immunological and oxidative status and investigated how birds cope physiologically with the effects of

  10. Measuring Dyspnea and Perceived Exertion in Healthy Adults and with Respiratory Disease: New Pictorial Scales

    OpenAIRE

    Pianosi, Paolo T; Zhang, Zhen; Hernandez, Paul; Huebner, Marianne

    2016-01-01

    Background Dyspnea or perceived exertion during exercise is most commonly measured using Borg or visual analog scales, created for use in adults. In contrast, pictorial scales have been promoted for children due to skepticism concerning applicability of the said scales in pediatrics. We sought to validate our newly created, pictorial Dalhousie Dyspnea and Perceived Exertion Scales in adult populations and compare ratings with the Borg scale. Methods Dyspnea and perceived exertion ratings obta...

  11. Human physiology in space

    Science.gov (United States)

    Vernikos, J.

    1996-01-01

    The universality of gravity (1 g) in our daily lives makes it difficult to appreciate its importance in morphology and physiology. Bone and muscle support systems were created, cellular pumps developed, neurons organised and receptors and transducers of gravitational force to biologically relevant signals evolved under 1g gravity. Spaceflight provides the only microgravity environment where systematic experimentation can expand our basic understanding of gravitational physiology and perhaps provide new insights into normal physiology and disease processes. These include the surprising extent of our body's dependence on perceptual information, and understanding the effect and importance of forces generated within the body's weightbearing structures such as muscle and bones. Beyond this exciting prospect is the importance of this work towards opening the solar system for human exploration. Although both appear promising, we are only just beginning to taste what lies ahead.

  12. Surgical Treatment of Chronic Exertional Compartment Syndrome in Pediatric Patients.

    Science.gov (United States)

    Beck, Jennifer J; Tepolt, Frances A; Miller, Patricia E; Micheli, Lyle J; Kocher, Mininder S

    2016-10-01

    Chronic exertional compartment syndrome (CECS) is a cause of leg pain in running athletes and is treated with fasciotomy after failure of nonoperative management. CECS is being seen with increased frequency in younger patients. The demographics and outcomes of fasciotomy for CECS in pediatric patients, including risk factors for treatment failure, have not been described. To describe characteristics of pediatric patients with CECS and determine surgical outcomes of the condition in this population. Case series; Level of evidence, 4. A retrospective review was performed for patients 18 years and younger treated surgically for CECS with compartment release at a single institution from 1995 to 2014. Demographic and condition characteristics, operative procedure, postoperative course, and clinical outcomes were recorded for 286 legs of 155 patients. Compartment pressure testing using the Pedowitz criteria confirmed the diagnosis in all patients. A total of 155 patients were included in the study (average patient age at presentation, 16.4 ± 1.38 years); 136 (88%) were female. All 155 patients presented with leg pain; of these patients, 8 (5%) also had neurologic symptoms, and 131 (85%) presented with bilateral symptoms requiring bilateral compartment release. Symptoms were chronic in nature, with duration over 1 year in 63% of patients. The primary sport was most commonly reported as running (25%), soccer (23%), or field hockey (12%); 50% of patients were multisport athletes. Of 286 legs, 138 (48%) had only anterior and/or lateral compartments released, while 84 (29.4%) had all 4 compartments released. Documented return to sport was seen in 79.5% of patients. Outcomes analysis was performed for 250 of 286 legs. Of these 250 legs, 47 (18.8%) had recurrent CECS requiring reoperation at a median of 1.3 years (interquartile range, 0.8-3.5) after initial compartment release. For each additional month between presentation and release, the odds of recurrence decreased by 12

  13. Endoscopic Fascia Release for Forearm Chronic Exertional Compartment Syndrome: Case Report and Surgical Technique

    National Research Council Canada - National Science Library

    Miller, Elizabeth A; Cobb, Anna L; Cobb, Tyson K

    Background: Chronic exertional compartment syndrome (CECS) of the forearm is traditionally treated with open compartment release requiring large incisions that can result in less than optimal esthetic results...

  14. Physiological modes of action of toxic chemicals in the nematode acrobeloides nanus

    NARCIS (Netherlands)

    Alda Alvarez, O.; Jager, T.; Redondo, E.M.; Kammenga, J.E.

    2006-01-01

    To gain a better understanding of the mechanisms through which a chemical exerts toxicity, a deeper insight is needed regarding the physiological processes that take place during a toxic stress. This issue can have important benefits for risk assessment, because it can contribute to a better

  15. Coronary Physiology During Exercise and Vasodilation in the Healthy Heart and in Severe Aortic Stenosis

    NARCIS (Netherlands)

    Lumley, Matthew; Williams, Rupert; Asrress, Kaleab N.; Arri, Satpal; Briceno, Natalia; Ellis, Howard; Rajani, Ronak; Siebes, Maria; Piek, Jan J.; Clapp, Brian; Redwood, Simon R.; Marber, Michael S.; Chambers, John B.; Perera, Divaka

    2016-01-01

    Severe aortic stenosis (AS) can manifest as exertional angina even in the presence of unobstructed coronary arteries. The authors describe coronary physiological changes during exercise and hyperemia in the healthy heart and in patients with severe AS. Simultaneous intracoronary pressure and flow

  16. Field physiology: physiological insights from animals in nature.

    Science.gov (United States)

    Costa, Daniel P; Sinervo, Barry

    2004-01-01

    Whereas comparative physiology documents the range of physiological variation across a range of organisms, field physiology provides insight into the actual mechanisms an organism employs to maintain homeostasis in its everyday life. This requires an understanding of an organism's natural history and is prerequisite to developing hypotheses about physiological mechanisms. This review focuses on a few areas of field physiology that exemplify how the underlying physiology could not have been understood without appropriate field measurements. The examples we have chosen highlight the methods and inference afforded by an application of this physiological analysis to organismal function in nature, often in extreme environments. The specific areas examined are diving physiology, the thermal physiology of large endothermic fishes, reproductive physiology of air breathing vertebrates, and endocrine physiology of reproductive homeostasis. These areas form a bridge from physiological ecology to evolutionary ecology. All our examples revolve around the central issue of physiological limits as they apply to organismal homeostasis. We view this theme as the cornerstone of physiological analysis and supply a number of paradigms on homeostasis that have been tested in the context of field physiology.

  17. Nigerian Journal of Physiological Sciences

    African Journals Online (AJOL)

    Nigerian Journal of Physiological Sciences (Niger. J. Physiol. Sci.) is a biannual publication of the Physiological Society of Nigeria. It covers diverse areas of research in physiological sciences, publishing reviews in current research areas and original laboratory and clinical research in physiological sciences. Other websites ...

  18. EXERTION DURING UPHILL, LEVEL AND DOWNHILL WALKING WITH AND WITHOUT HIKING POLES

    Directory of Open Access Journals (Sweden)

    Stephane Perrey

    2008-03-01

    Full Text Available This study examined the effects of poles when walking on the rate of perceived exertion (RPE, physiological and kinematics parameters, and upon the mean ratio between locomotor and respiratory rhythms. Twelve healthy male and female volunteers, aged 22 to 49 years old, completed on a motorized treadmill in a counterbalanced randomized order 12 walking trials for 10 min at an individually preferred walking speed, with three grades (horizontal level, uphill or downhill with a slope of 15%, with and without hiking poles and a load carriage of 15% of body mass. During all testing sessions, heart rate (HR, oxygen consumption (VO2, ventilation (VE, tidal volume (VT, breathing frequency (Bf, and stride frequency were recorded continuously during the last 5-min of each trial. At the end of each trial, subjects were asked to give RPE. Energy cost (EC and VE increased significantly with the grade (-15% < 0% < +15% and with the carrying load. VT was significantly less important with hiking poles, while Bf was significantly more elevated. VO2 and EC increased (p < 0.05 with the use of the hiking poles only during the downhill trials. No significant effect of poles was observed on HR, RPE, and preferred walking speed. The average ratio between the locomotor and respiratory frequencies was significantly influenced by the three experimental factors tested. There was a significant relationship between average ratio of leg movement per breath and EC of walking among all conditions (r = 0.83, n = 12. These results suggest that the use of the hiking poles had a significant influence on the respiratory and energetic responses only during downhill walking

  19. The Face of Physiology

    Directory of Open Access Journals (Sweden)

    Paul White

    2008-10-01

    Full Text Available This article explores the relationship between the physiology of the emotions and the display of character in Victorian Britain. Charles Bell and others had begun to link certain physiological functions, such as respiration, with the expression of feelings such as fear, regarding the heart and other internal organs as instruments by which the emotions were made visible. But a purely functional account of the emotions, which emerged through the development of reflex physiology during the second half of the century, would dramatically alter the nature of feelings and the means of observing them. At the same time, instinctual or acquired sympathy, which had long underpinned the accurate reading of expressions, became a problem to be surmounted by new 'objectively'. Graphic recording instruments measuring a variety of physiological functions and used with increasing frequency in clinical diagnostics became of fundamental importance for tracing the movement of feelings during the period prior to the development of cinematography. They remained, in the form of devices such as the polygraph, a crucial and controversial means of measuring affective states, beneath the potentially deceptive surface of the body.

  20. Starting Physiology: Bioelectrogenesis

    Science.gov (United States)

    Baptista, Vander

    2015-01-01

    From a Cartesian perspective of rational analysis, the electric potential difference across the cell membrane is one of the fundamental concepts for the study of physiology. Unfortunately, undergraduate students often struggle to understand the genesis of this energy gradient, which makes the teaching activity a hard task for the instructor. The…

  1. Physiology of alpine skiing.

    Science.gov (United States)

    Turnbull, J R; Kilding, A E; Keogh, J W L

    2009-04-01

    The extreme environment of cold, altitude and movement complexity makes alpine ski racing a difficult sport to study. This review comprises >30 years of research and includes 29 on-snow investigations of specific physiology relating to the various ski racing disciplines, nine off-snow investigations of the physiological capacities of ski racers of varying ability and four review articles. Alpine ski racing appears to involve a complex integration of many different physiological systems, none of which may be more important than the other to overall performance. While technical ability appears to be the greatest influencing factor on performance, the ability to continually exhibit technical competence through a long competitive season requires high capabilities within all physiological systems. Identifying the optimal approach and time to concurrently develop these systems is a challenge for sport scientists. Further research is required using modern portable investigative tools for determining aerobic and anaerobic demands and abilities, especially in the areas of muscle function and relative energy system contribution during both single and multiple runs on varying terrain.

  2. Physiology of Sleep.

    Science.gov (United States)

    Carley, David W; Farabi, Sarah S

    2016-02-01

    IN BRIEF Far from a simple absence of wakefulness, sleep is an active, regulated, and metabolically distinct state, essential for health and well-being. In this article, the authors review the fundamental anatomy and physiology of sleep and its regulation, with an eye toward interactions between sleep and metabolism.

  3. Physiology Flies with Time.

    Science.gov (United States)

    Sehgal, Amita

    2017-11-30

    The 2017 Nobel Prize in Medicine or Physiology has been awarded to Jeffrey Hall, Michael Rosbash, and Michael Young for elucidating molecular mechanisms of the circadian clock. From studies beginning in fruit flies, we now know that circadian regulation pervades most biological processes and has strong ties to human health and disease. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Physiology of Breastfeeding

    Science.gov (United States)

    This powerpoint presentation summaries physiology of lactation and the impact of a variety of clinical practices on lactation from delivery through weaning. Factors that inhibit lactogenesis stage II are explained, including retained placenta, excess blood loss during delivery, and hypoplastic brea...

  5. The Physiology of Motivation.

    Science.gov (United States)

    Stellar, Eliot

    1994-01-01

    A theory of the physiology of motivation is presented. The basic assumption is that the amount of motivated behavior is a direct function of the amount of activity in certain excitatory centers of the hypothalamus. Activities of these centers are determined by factors in four general classes. (SLD)

  6. Research on gravitational physiology

    Science.gov (United States)

    Brown, A. H.; Dahl, A. O.

    1974-01-01

    The topic of gravitational plant physiology was studied through aspects of plant development (in ARABIDOPSIS) and of behavior (in HELIANTHUS) as these were affected by altered g experience. The effect of increased g levels on stem polarity (in COLEUS) was also examined.

  7. Renal Physiology of Pregnancy

    Science.gov (United States)

    Cheung, Katharine L.; Lafayette, Richard A.

    2014-01-01

    Pregnancy involves remarkable orchestration of physiologic changes. The kidneys are central players in the evolving hormonal milieu of pregnancy, responding and contributing to the changes in the environment for the pregnant woman and fetus. The functional impact of pregnancy on kidney physiology is widespread, involving practically all aspects of kidney function. The glomerular filtration rate increases 50% with subsequent decrease in serum creatinine, urea, and uric acid values. The threshold for thirst and antidiuretic hormone secretion are depressed, resulting in lower osmolality and serum sodium levels. Blood pressure drops approximately 10 mmHg by the second trimester despite a gain in intravascular volume of 30% to 50%. The drop in systemic vascular resistance is multifactorial, attributed in part to insensitivity to vasoactive hormones, and leads to activation of the renin-aldosterone-angiostensin system. A rise in serum aldosterone results in a net gain of approximately 1000 mg of sodium. A parallel rise in progesterone protects the pregnant woman from hypokalemia. The kidneys increase in length and volume, and physiologic hydronephrosis occurs in up to 80% of women. This review will provide an understanding of these important changes in kidney physiology during pregnancy, which is fundamental in caring for the pregnant patient. PMID:23928384

  8. Avian reproductive physiology

    Science.gov (United States)

    Gee, G.F.; Gibbons, Edward F.; Durrant, Barbara S.; Demarest, Jack

    1995-01-01

    Knowledge of the many physiological factors associated with egg production , fertility, incubation, and brooding in nondomestic birds is limited. Science knows even less about reproduction in most of the 238 endangered or threatened birds. This discussion uses studies of nondomestic and, when necessary, domestic birds to describe physiological control of reproduction. Studies of the few nondomestic avian species show large variation in physiological control of reproduction. Aviculturists, in order to successfully propagate an endangered bird, must understand the bird's reproductive peculiarities. First, investigators can do studies with carefully chosen surrogate species, but eventually they need to confirm the results in the target endangered bird. Studies of reproduction in nondomestic birds increased in the last decade. Still, scientists need to do more comparative studies to understand the mechanisms that control reproduction in birds. New technologies are making it possible to study reproductive physiology of nondomestic species in less limiting ways. These technologies include telemetry to collect information without inducing stress on captives (Howey et al., 1987; Klugman, 1987), new tests for most of the humoral factors associated with reproduction, and the skill to collect small samples and manipulate birds without disrupting the physiological mechanisms (Bercovitz et al., 1985). Managers are using knowledge from these studies to improve propagation in zoological parks, private and public propagation facilities, and research institutions. Researchers need to study the control of ovulation, egg formation, and oviposition in the species of nondomestic birds that lay very few eggs in a season, hold eggs in the oviduct for longer intervals, or differ in other ways from the more thoroughly studied domestic birds. Other techniques that would enhance propagation for nondomestlc birds include tissue culture of cloned embryonic cells, cryopreservation of embryos

  9. Identification of differentially expressed sequences in bud ...

    African Journals Online (AJOL)

    The suppression subtractive hybridization (SSH) method conducted to generate large-scale expressed sequence tags (EST) was designed to identify gene candidates related to the morphological and physiological differences between the stage before bud differentiation and the stage of bud differentiation of lily. The results ...

  10. Protein kinase C is differentially regulated by thrombin, insulin, and epidermal growth factor in human mammary tumor cells

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, M.L.; Tellez-Inon, M.T. (Instituto de Ingenieria Genetica y Biologia Molecular, Buenos Aires (Argentina)); Medrano, E.E.; Cafferatta, E.G.A. (Instituto de Investigaciones Bioquimicas Fundacion Campomar, Buenos Aires (Argentina))

    1988-03-01

    The exposure of serum-deprived mammary tumor cells MCF-7 and T-47D to insulin, thrombin, and epidermal growth factor (EGF) resulted in dramatic modifications in the activity and in the translocation capacity of protein kinase C from cytosol to membrane fractions. Insulin induces a 600% activation of the enzyme after 5 h of exposure to the hormone in MCF-7 cells; thrombin either activates (200% in MCF-7) or down-regulates (in T-47D), and EGF exerts only a moderate effect. Thus, the growth factors studied modulate differentially the protein kinase C activity in human mammary tumor cells. The physiological significance of the results obtained are discussed in terms of the growth response elicited by insulin, thrombin, and EGF.

  11. Differential manifolds

    CERN Document Server

    Kosinski, Antoni A

    2007-01-01

    The concepts of differential topology form the center of many mathematical disciplines such as differential geometry and Lie group theory. Differential Manifolds presents to advanced undergraduates and graduate students the systematic study of the topological structure of smooth manifolds. Author Antoni A. Kosinski, Professor Emeritus of Mathematics at Rutgers University, offers an accessible approach to both the h-cobordism theorem and the classification of differential structures on spheres.""How useful it is,"" noted the Bulletin of the American Mathematical Society, ""to have a single, sho

  12. Differential systems

    CERN Document Server

    Thomas, Joseph Miller

    1937-01-01

    The main goal of this book is to present the theory of systems of partial differential equations and the theory of Pfaffian systems so as to exhibit clearly the relations between them. In presenting the theory of Pfaffian systems, the author develops, in detail, the theories of Grassmann algebras and rings with differentiation. In particular, following Grassmann and É. Cartan, he introduces and freely uses what is now known as a ring of differential forms with functional coefficients. In presenting the theory of systems of partial differential equations, the author concentrates on the existenc

  13. Galectin-1 exerts inhibitory effects during DENV-1 infection.

    Directory of Open Access Journals (Sweden)

    Karina Alves Toledo

    Full Text Available Dengue virus (DENV is an enveloped RNA virus that is mosquito-transmitted and can infect a variety of immune and non-immune cells. Response to infection ranges from asymptomatic disease to a severe disorder known as dengue hemorrhagic fever. Despite efforts to control the disease, there are no effective treatments or vaccines. In our search for new antiviral compounds to combat infection by dengue virus type 1 (DENV-1, we investigated the role of galectin-1, a widely-expressed mammalian lectin with functions in cell-pathogen interactions and immunoregulatory properties. We found that DENV-1 infection of cells in vitro exhibited caused decreased expression of Gal-1 in several different human cell lines, suggesting that loss of Gal-1 is associated with virus production. In test of this hypothesis we found that exogenous addition of human recombinant Gal-1 (hrGal-1 inhibits the virus production in the three different cell types. This inhibitory effect was dependent on hrGal-1 dimerization and required its carbohydrate recognition domain. Importantly, the inhibition was specific for hrGal-1, since no effect was observed using recombinant human galectin-3. Interestingly, we found that hrGal-1 directly binds to dengue virus and acts, at least in part, during the early stages of DENV-1 infection, by inhibiting viral adsorption and its internalization to target cells. To test the in vivo role of Gal-1 in DENV infection, Gal-1-deficient-mice were used to demonstrate that the expression of endogenous Galectin-1 contributes to resistance of macrophages to in vitro-infection with DENV-1 and it is also important to physiological susceptibility of mice to in vivo infection with DENV-1. These results provide novel insights into the functions of Gal-1 in resistance to DENV infection and suggest that Gal-1 should be explored as a potential antiviral compound.

  14. Chronic exertional compartment syndrome of the superficial posterior compartment: Soleus syndrome

    OpenAIRE

    Christopher E Gross; Bela J Parekh; Samuel B Adams; Selene G Parekh

    2015-01-01

    Chronic exertional compartment syndrome (CECS) represents the second most-common cause of exertional leg pain with incidence of 27-33%. CECS of the superficial posterior compartment, or soleus syndrome, is rare and has only been discussed briefly in the literature. We discuss the management of two patients with bilateral soleus syndrome or CECS of the superficial posterior compartment.

  15. Stiffness and thickness of fascia do not explain chronic exertional compartment syndrome

    DEFF Research Database (Denmark)

    Dahl, Morten; Hansen, Philip; Stål, Per

    2011-01-01

    Chronic exertional compartment syndrome is diagnosed based on symptoms and elevated intramuscular pressure and often is treated with fasciotomy. However, what contributes to the increased intramuscular pressure remains unknown.......Chronic exertional compartment syndrome is diagnosed based on symptoms and elevated intramuscular pressure and often is treated with fasciotomy. However, what contributes to the increased intramuscular pressure remains unknown....

  16. Chronic exertional compartment syndrome of the superficial posterior compartment: Soleus syndrome.

    Science.gov (United States)

    Gross, Christopher E; Parekh, Bela J; Adams, Samuel B; Parekh, Selene G

    2015-01-01

    Chronic exertional compartment syndrome (CECS) represents the second most-common cause of exertional leg pain with incidence of 27-33%. CECS of the superficial posterior compartment, or soleus syndrome, is rare and has only been discussed briefly in the literature. We discuss the management of two patients with bilateral soleus syndrome or CECS of the superficial posterior compartment.

  17. Effects of music and video on perceived exertion during high-intensity exercise

    Directory of Open Access Journals (Sweden)

    Enoch C. Chow

    2017-03-01

    Conclusion: Music and video in combination may result in lower perceived exertion during high-intensity exercise when compared to music or video in isolation. Future research will be necessary to test if reductions in perceived exertion in response to dissociative attentional stimuli have implications for exercise adherence.

  18. Dynamics of Perceived Exertion in Constant-Power Cycling: Time- and Workload-Dependent Thresholds

    Science.gov (United States)

    Balagué, Natàlia; Hristovski, Robert; García, Sergi; Aguirre, Cecilia; Vázquez, Pablo; Razon, Selen; Tenenbaum, Gershon

    2015-01-01

    Purpose: The purpose of this study was to test the dynamics of perceived exertion shifts (PES) as a function of time and workload during constant-power cycling. Method: Fifty-two participants assigned to 4 groups performed a cycling task at 4 different constant workloads corresponding to their individual rates of perceived exertion (RPEs = 13, 15,…

  19. Phospholipases of Mineralization Competent Cells and Matrix Vesicles: Roles in Physiological and Pathological Mineralizations

    Directory of Open Access Journals (Sweden)

    René Buchet

    2013-03-01

    Full Text Available The present review aims to systematically and critically analyze the current knowledge on phospholipases and their role in physiological and pathological mineralization undertaken by mineralization competent cells. Cellular lipid metabolism plays an important role in biological mineralization. The physiological mechanisms of mineralization are likely to take place in tissues other than in bones and teeth under specific pathological conditions. For instance, vascular calcification in arteries of patients with renal failure, diabetes mellitus or atherosclerosis recapitulates the mechanisms of bone formation. Osteoporosis—a bone resorbing disease—and rheumatoid arthritis originating from the inflammation in the synovium are also affected by cellular lipid metabolism. The focus is on the lipid metabolism due to the effects of dietary lipids on bone health. These and other phenomena indicate that phospholipases may participate in bone remodelling as evidenced by their expression in smooth muscle cells, in bone forming osteoblasts, chondrocytes and in bone resorbing osteoclasts. Among various enzymes involved, phospholipases A1 or A2, phospholipase C, phospholipase D, autotaxin and sphingomyelinase are engaged in membrane lipid remodelling during early stages of mineralization and cell maturation in mineralization-competent cells. Numerous experimental evidences suggested that phospholipases exert their action at various stages of mineralization by affecting intracellular signaling and cell differentiation. The lipid metabolites—such as arachidonic acid, lysophospholipids, and sphingosine-1-phosphate are involved in cell signaling and inflammation reactions. Phospholipases are also important members of the cellular machinery engaged in matrix vesicle (MV biogenesis and exocytosis. They may favour mineral formation inside MVs, may catalyse MV membrane breakdown necessary for the release of mineral deposits into extracellular matrix (ECM, or

  20. Differentiating knowledge, differentiating (occupational) practice

    OpenAIRE

    Hordern, J

    2016-01-01

    This paper extends arguments for differentiating knowledge into conceptualisations of occupational practice. It is argued that specialised forms of knowledge and practice require recognition and differentiation in ways that many contemporary approaches to practice theory deny. Drawing on Hager’s interpretation of MacIntyre is it suggested that occupational practices are differentiated from non-occupational practices by their ‘purposiveness’, and by how their internal and external goods relate...

  1. Constraint Differentiation

    DEFF Research Database (Denmark)

    Mödersheim, Sebastian Alexander; Basin, David; Viganò, Luca

    2010-01-01

    We introduce constraint differentiation, a powerful technique for reducing search when model-checking security protocols using constraint-based methods. Constraint differentiation works by eliminating certain kinds of redundancies that arise in the search space when using constraints to represent...

  2. Hair and Physiological Baldness

    Science.gov (United States)

    Mercantini, Edward S.

    1965-01-01

    Human hair is one of the structures of the body about which little is generally known. Disease affecting the hair is often minimized or ignored by physicians because of lack of knowledge of this rudimentary organ. However, the patient's attitude toward hair loss is very different from the doctor's and he feels great concern about such loss. The development, growth and morphology of human hair are briefly presented. Experimental work which will increase our knowledge of hair growth and loss is reviewed. The various forms of physiological alopecia from birth onward are discussed, with special emphasis on the least-known type of physiological baldness, “male-pattern baldness” in the adult female. PMID:14312445

  3. Renal phosphate handling: Physiology

    Directory of Open Access Journals (Sweden)

    Narayan Prasad

    2013-01-01

    Full Text Available Phosphorus is a common anion. It plays an important role in energy generation. Renal phosphate handling is regulated by three organs parathyroid, kidney and bone through feedback loops. These counter regulatory loops also regulate intestinal absorption and thus maintain serum phosphorus concentration in physiologic range. The parathyroid hormone, vitamin D, Fibrogenic growth factor 23 (FGF23 and klotho coreceptor are the key regulators of phosphorus balance in body.

  4. Integrative Physiology of Fasting.

    Science.gov (United States)

    Secor, Stephen M; Carey, Hannah V

    2016-03-15

    Extended bouts of fasting are ingrained in the ecology of many organisms, characterizing aspects of reproduction, development, hibernation, estivation, migration, and infrequent feeding habits. The challenge of long fasting episodes is the need to maintain physiological homeostasis while relying solely on endogenous resources. To meet that challenge, animals utilize an integrated repertoire of behavioral, physiological, and biochemical responses that reduce metabolic rates, maintain tissue structure and function, and thus enhance survival. We have synthesized in this review the integrative physiological, morphological, and biochemical responses, and their stages, that characterize natural fasting bouts. Underlying the capacity to survive extended fasts are behaviors and mechanisms that reduce metabolic expenditure and shift the dependency to lipid utilization. Hormonal regulation and immune capacity are altered by fasting; hormones that trigger digestion, elevate metabolism, and support immune performance become depressed, whereas hormones that enhance the utilization of endogenous substrates are elevated. The negative energy budget that accompanies fasting leads to the loss of body mass as fat stores are depleted and tissues undergo atrophy (i.e., loss of mass). Absolute rates of body mass loss scale allometrically among vertebrates. Tissues and organs vary in the degree of atrophy and downregulation of function, depending on the degree to which they are used during the fast. Fasting affects the population dynamics and activities of the gut microbiota, an interplay that impacts the host's fasting biology. Fasting-induced gene expression programs underlie the broad spectrum of integrated physiological mechanisms responsible for an animal's ability to survive long episodes of natural fasting. Copyright © 2016 John Wiley & Sons, Inc.

  5. Differential equations

    CERN Document Server

    Barbu, Viorel

    2016-01-01

    This textbook is a comprehensive treatment of ordinary differential equations, concisely presenting basic and essential results in a rigorous manner. Including various examples from physics, mechanics, natural sciences, engineering and automatic theory, Differential Equations is a bridge between the abstract theory of differential equations and applied systems theory. Particular attention is given to the existence and uniqueness of the Cauchy problem, linear differential systems, stability theory and applications to first-order partial differential equations. Upper undergraduate students and researchers in applied mathematics and systems theory with a background in advanced calculus will find this book particularly useful. Supplementary topics are covered in an appendix enabling the book to be completely self-contained.

  6. Pavlov and integrative physiology.

    Science.gov (United States)

    Smith, G P

    2000-09-01

    Ivan Petrovich Pavlov was the first physiologist to win the Nobel Prize. The Prize was given in 1904 for his research on the neural control of salivary, gastric, and pancreatic secretion. A major reason for the success and novelty of his research was the use of unanesthetized dogs surgically prepared with chronic fistulas or gastric pouches that permitted repeated experiments in the same animal for months. Pavlov invented this chronic method because of the limitations he perceived in the use of acute anesthetized animals for investigating physiological systems. By introducing the chronic method and by showing its experimental advantages, Pavlov founded modern integrative physiology. This paper reviews Pavlov's journey from his birthplace in a provincial village in Russia to Stockholm to receive the Prize. It begins with childhood influences, describes his training and mentors, summarizes the major points of his research by reviewing his book Lectures on the Work of the Digestive Glands, and discusses his views on the relationship between physiology and medicine.

  7. The Dipeptides Ile-Tyr and Ser-Tyr Exert Distinct Effects on Catecholamine Metabolism in the Mouse Brainstem.

    Science.gov (United States)

    Moriyasu, Kazuki; Ichinose, Takashi; Nakahata, Akane; Tanaka, Mitsuru; Matsui, Toshiro; Furuya, Shigeki

    2016-01-01

    Catecholamine synthesis and transmission in the brain are influenced by the availability of Tyr in the body. In this study, we compared the effects of oral administration of Tyr-containing dipeptides Ile-Tyr, Ser-Tyr, and Tyr-Pro with Tyr alone on catecholamine metabolism in the mouse brainstem. Among these dipeptides, Ile-Tyr administration led to increases in dopamine, the dopamine metabolites homovanillic acid, and 3,4-dihydroxyphenylacetic acid, compared to administration of Ser-Tyr, Tyr-Pro, or Tyr alone. In comparison, administration of Ser-Tyr induced significantly increasing noradrenaline turnover, while Tyr-Pro administration suppressed dopamine turnover. Therefore, oral administration of Ile-Tyr, Ser-Tyr, and Tyr-Pro differentially affected metabolism of dopamine and noradrenaline. These observations strongly suggest that Tyr-containing dipeptides exert distinct effects on catecholamine metabolism in the brainstem when ingested orally.

  8. Gastrin and gastric epithelial physiology

    Science.gov (United States)

    Dockray, G J

    1999-01-01

    Transepithelial transducing cells, particularly the gastrin (G) cell, co-ordinate gastric acid secretion with the arrival of food in the stomach. Recent work suggests that multiple active products are generated from the gastrin precursor, and that there are multiple control points in gastrin biosynthesis. Biosynthetic precursors and intermediates (progastrin and Gly-gastrins) are putative growth factors; their products, the amidated gastrins, regulate epithelial cell proliferation, the differentiation of acid-producing parietal cells and histamine-secreting enterochromaffin-like (ECL) cells, and the expression of genes associated with histamine synthesis and storage in ECL cells, as well as acutely stimulating acid secretion. Gastrin also stimulates the production of members of the epidermal growth factor (EGF) family, which in turn inhibit parietal cell function but stimulate the growth of surface epithelial cells. Plasma gastrin concentrations are elevated in subjects with Helicobacter pylori, who are known to have increased risk of duodenal ulcer disease and gastric cancer. Studies of the physiology of gastrin may therefore contribute to an understanding of the mechanisms relevant to major upper gastrointestinal tract disease. PMID:10381581

  9. Motivational incentives lead to a strong increase in lateral prefrontal activity after self-control exertion.

    Science.gov (United States)

    Luethi, Matthias S; Friese, Malte; Binder, Julia; Boesiger, Peter; Luechinger, Roger; Rasch, Björn

    2016-10-01

    Self-control is key to success in life. Initial acts of self-control temporarily impair subsequent self-control performance. Why such self-control failures occur is unclear, with prominent models postulating a loss of a limited resource vs a loss of motivation, respectively. Here, we used functional magnetic resonance imaging to identify the neural correlates of motivation-induced benefits on self-control. Participants initially exerted or did not exert self-control. In a subsequent Stroop task, participants performed worse after exerting self-control, but not if they were motivated to perform well by monetary incentives. On the neural level, having exerted self-control resulted in decreased activation in the left inferior frontal gyrus. Increasing motivation resulted in a particularly strong activation of this area specifically after exerting self-control. Thus, after self-control exertion participants showed more prefrontal neural activity without improving performance beyond baseline level. These findings suggest that impaired performance after self-control exertion may not exclusively be due to a loss of motivation. © The Author (2016). Published by Oxford University Press. For Permissions, please email: journals.permissions@oup.com.

  10. Blood pressure response to physical exertion in adolescents: influence of overweight and obesity.

    Science.gov (United States)

    Carletti, Luciana; Rodrigues, Anabel Nunes; Perez, Anselmo José; Vassallo, Dalton Valentim

    2008-07-01

    The acute blood pressure response to physical exertion has been used as an indicator of the risk of developing hypertension. The factors associated with this response need to be clarified for timely intervention in preventing hypertensive disease. To describe the response of cardiovascular variables to acute physical exertion in overweight adolescents using cardiopulmonary exercise testing. The sample consisted of 104 adolescents (56 boys and 48 girls), divided into two groups: the obese/overweight group (OOG) and the eutrophic group (EG). The following variables were measured: anthropometric (weight, height, and BMI), body composition (skin fold thickness), as well as hemodynamic variables such as systolic arterial pressure (SAP), diastolic arterial pressure (DAP), and heart rate (HR), at rest and at maximal physical exertion during the cardiopulmonary test. In the male group, the greatest values of systolic arterial pressure at rest were recorded in the OOG as compared to the EG (113 +/- 13 vs 106 +/- 8 mmHg; p = 0.009), pre-exertion SAP (120 +/- 14 vs 109 +/- 10 mmHg; p = 0.003), and SAP during maximal exertion conditions (156 +/- 20 vs 146 +/- 14 mmHg; p = 0.03). In the female group, only pre-exertion SAP was higher in the overweight group as compared to the eutrophic girls (114 +/- 11 vs 106 +/- 10 mmHg; p = 0.009). The response of arterial blood pressure during physical exercise was most exacerbated in obese adolescents as compared to eutrophic teens, suggesting greater reactivity to physical exertion.

  11. Differential games

    CERN Document Server

    Friedman, Avner

    2006-01-01

    This volume lays the mathematical foundations for the theory of differential games, developing a rigorous mathematical framework with existence theorems. It begins with a precise definition of a differential game and advances to considerations of games of fixed duration, games of pursuit and evasion, the computation of saddle points, games of survival, and games with restricted phase coordinates. Final chapters cover selected topics (including capturability and games with delayed information) and N-person games.Geared toward graduate students, Differential Games will be of particular interest

  12. Capability and recruitment patterns of trunk during isometric uniaxial and biaxial upright exertion.

    Science.gov (United States)

    Sheikhzadeh, Ali; Parnianpour, Mohamad; Nordin, Margareta

    2008-06-01

    Work-related risk factors of low back disorders have been identified to be external moments, awkward postures, and asymmetrical dynamic lifting amongst others. The distinct role of asymmetry of load versus posture is hard to discern from the literature. Hence, the aim of this study is to measure isometric trunk exertions at upright standing posture at different exertion level and degree of asymmetry to further delineate the effects of exertion level and asymmetry on neuromuscular capability response. Fifteen healthy volunteers randomly performed trunk exertions at three levels (30%, 60%, and 100% of maximum voluntary exertion and five different angles (0 degrees , 45 degrees , 90 degrees , 135 degrees , and 180 degrees ) of normalized resultant moments. During each trial, the normalized EMG activity of 10 selected trunk muscles was quantified. The EMG activity of the 10 trunk muscles was significantly (Presultant moment, and their interactions. The controllability of the torque generation was reduced in biaxial exertions. The capability to generate and control the required trunk moments is significantly lowered during biaxial trunk exertions, while all muscles present higher EMG activity. These results suggest that the trunk muscles will be taxed higher while performing biaxial exertion tasks, increasing muscle fatigue possibly leading to a higher probability of low back injury. The prediction of biaxial trunk performance based on uniaxial data will result in an overestimation of capability and controllability of the trunk during physically demanding tasks. This study provides a better understanding of the potential mechanisms of injury during asymmetrical and biaxial trunk exertion during work-related tasks.

  13. Synchrony and exertion during dance independently raise pain threshold and encourage social bonding.

    Science.gov (United States)

    Tarr, Bronwyn; Launay, Jacques; Cohen, Emma; Dunbar, Robin

    2015-10-01

    Group dancing is a ubiquitous human activity that involves exertive synchronized movement to music. It is hypothesized to play a role in social bonding, potentially via the release of endorphins, which are analgesic and reward-inducing, and have been implicated in primate social bonding. We used a 2 × 2 experimental design to examine effects of exertion and synchrony on bonding. Both demonstrated significant independent positive effects on pain threshold (a proxy for endorphin activation) and in-group bonding. This suggests that dance which involves both exertive and synchronized movement may be an effective group bonding activity. © 2015 The Authors.

  14. Posterior Tibial Arterial System Deficiency Mimicking Chronic Exertional Compartment Syndrome: A Case Report.

    Science.gov (United States)

    Lavery, Kyle P; Parcells, Bertrand W; Hosea, Timothy

    2016-01-01

    A 15-year-old female competitive high school basketball player presented as an outpatient with a 3-month history of bilateral exertional calf pain. Patient history and compartment pressure measurements were consistent with the diagnosis of chronic exertional compartment syndrome, and the patient underwent bilateral fasciotomies. Postoperatively, her symptoms recurred and she was found to have a deficient posterior tibial arterial system bilaterally, as confirmed on advanced imaging. We advocate the careful consideration of vascular etiologies in athletes who present with exertional leg pain.

  15. Physical exercise at the workplace reduces perceived physical exertion during healthcare work

    DEFF Research Database (Denmark)

    Jakobsen, Markus Due; Sundstrup, Emil; Brandt, Mikkel

    2015-01-01

    exercise may decrease physical exertion during work. This study investigates the effect of workplace-based versus home-based physical exercise on physical exertion during work (WRPE) among healthcare workers. METHODS: 200 female healthcare workers (age: 42.0, body mass index: 24.1, average pain intensity...... was 0.43 and 0.13, respectively. CONCLUSIONS: Physical exercise performed at the workplace appears more effective than home-based exercise in reducing physical exertion during daily work tasks in healthcare workers....

  16. The emergence of Applied Physiology within the discipline of Physiology.

    Science.gov (United States)

    Tipton, Charles M

    2016-08-01

    Despite the availability and utilization of the physiology textbooks authored by Albrecht von Haller during the 18th century that heralded the modern age of physiology, not all physicians or physiologists were satisfied with its presentation, contents, or application to medicine. Initial reasons were fundamental disagreements between the "mechanists," represented by Boerhaave, Robinson, and von Haller, and the "vitalists," represented by the faculty and graduates of the Montpellier School of Medicine in France, notably, Bordeu and Barthez. Subsequently, objections originated from Europe, United Kingdom, and the United States in publications that focused not only on the teaching of physiology to medical and secondary students, but on the specific applications of the content of physiology to medicine, health, hygiene, pathology, and chronic diseases. At the turn of the 20th century, texts began to appear with applied physiology in their titles and in 1926, physician Samson Wright published a textbook entitled Applied Physiology that was intended for both medical students and the medical profession. Eleven years later, physicians Best and Taylor published The Physiological Basis of Medical Practice: A University of Toronto Texbook in Applied Physiology Although both sets of authors defined the connection between applied physiology and physiology, they failed to define the areas of physiology that were included within applied physiology. This was accomplished by the American Physiological Society (APS) Publications Committee in 1948 with the publication of the Journal of Appplied Physiology, that stated the word "applied" would broadly denote human physiology whereas the terms stress and environment would broadly include work, exercise, plus industrial, climatic and social factors. NIH established a study section (SS) devoted to applied physiology in 1964 which remained active until 2001 when it became amalgamated into other SSs. Before the end of the 20th century when

  17. Seasonal changes in reindeer physiology

    Directory of Open Access Journals (Sweden)

    A. Reeta Pösö

    2005-04-01

    Full Text Available The seasonal changes in the photoperiod, temperature and availability of food need to be converted to hormonal signals in order to induce adaptations in the physiology of the reindeer. The most reliable of the seasonal changes in the environment is the photoperiod, which affects the reindeer physiology through pineal gland and its hormone, melatonin. Usually there are large diurnal changes in the concentration of melatonin, but in the reindeer the daily rhythm disappears during the arctic summer to return again in the autumn. Seasonal changes in melatonin secretion are involved in the regulation of reproduction, the growth of pelage, thermogenesis, body mass and immune function. Melatonin may exert its effects through gene activation, but the mechanisms are not completely understood. Other hormones that show seasonality are thyroid hormones, insulin and leptin. Thus the observed physiological changes are a result of actions of several hormones. Appetite, energy production and thermogenesis are all vital for survival. During winter, when energy balance is negative, the reindeer uses mainly body fat for energy production. The use of fat stores is economical as the rate of lipolysis is controlled and the use of fatty acids in tissues such as muscle decreases. Only in severe starvation the rate of lipolysis increases enough to give rise to accumulation of ketone bodies. The protein mass is maintained and only in starved individuals muscle protein is used for energy production. The winter feed of the reindeer, the lichens, is poor in nitrogen and the nitrogen balance during winter is strongly negative. Reindeer responds to limited availability of nitrogen by increasing the recycling of urea into rumen. In general the adaptation of reindeer physiology enables the reindeer to survive the winter and although several aspects are known many others require further studies.Abstract in Finnish / Tiivistelmä: Valaistus, lämpötila ja ravinnon saatavuus

  18. Gastrointestinal Physiology and Function.

    Science.gov (United States)

    Greenwood-Van Meerveld, Beverley; Johnson, Anthony C; Grundy, David

    2017-01-01

    The gastrointestinal (GI) system is responsible for the digestion and absorption of ingested food and liquids. Due to the complexity of the GI tract and the substantial volume of material that could be covered under the scope of GI physiology, this chapter briefly reviews the overall function of the GI tract, and discusses the major factors affecting GI physiology and function, including the intestinal microbiota, chronic stress, inflammation, and aging with a focus on the neural regulation of the GI tract and an emphasis on basic brain-gut interactions that serve to modulate the GI tract. GI diseases refer to diseases of the esophagus, stomach, small intestine, colon, and rectum. The major symptoms of common GI disorders include recurrent abdominal pain and bloating, heartburn, indigestion/dyspepsia, nausea and vomiting, diarrhea, and constipation. GI disorders rank among the most prevalent disorders, with the most common including esophageal and swallowing disorders, gastric and peptic ulcer disease, gastroparesis or delayed gastric emptying, irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD). Many GI disorders are difficult to diagnose and their symptoms are not effectively managed. Thus, basic research is required to drive the development of novel therapeutics which are urgently needed. One approach is to enhance our understanding of gut physiology and pathophysiology especially as it relates to gut-brain communications since they have clinical relevance to a number of GI complaints and represent a therapeutic target for the treatment of conditions including inflammatory diseases of the GI tract such as IBD and functional gut disorders such as IBS.

  19. Differential topology

    CERN Document Server

    Mukherjee, Amiya

    2015-01-01

    This book presents a systematic and comprehensive account of the theory of differentiable manifolds and provides the necessary background for the use of fundamental differential topology tools. The text includes, in particular, the earlier works of Stephen Smale, for which he was awarded the Fields Medal. Explicitly, the topics covered are Thom transversality, Morse theory, theory of handle presentation, h-cobordism theorem, and the generalised Poincaré conjecture. The material is the outcome of lectures and seminars on various aspects of differentiable manifolds and differential topology given over the years at the Indian Statistical Institute in Calcutta, and at other universities throughout India. The book will appeal to graduate students and researchers interested in these topics. An elementary knowledge of linear algebra, general topology, multivariate calculus, analysis, and algebraic topology is recommended.

  20. Pioneering in gravitational physiology

    Science.gov (United States)

    Soffen, G. A.

    1983-01-01

    Gravity affects biology at almost all levels above that of the cell organelle. Attention is presently given to progress made in the understanding of gravitational effects through studies employing centrifuges, clinostats, inverted preparations, linear devices, water immersion, free fall, and short- and long-term spaceflight. The cardiovascular changes which cause malaise and illness during the first few days of extended space missions are the direct result of fluid translocation from the lower extremities. Upon reentry, there is hypovolumnia and a cardiovascular deconditioning that can include tachycardia, changes in arterial blood pressure, narrow pulse pressure, and syncope. Attention is also given to NASA's gravitational physiology reseach program.

  1. Conservation physiology of marine fishes

    DEFF Research Database (Denmark)

    Jørgensen, Christian; Peck, Myron A.; Antognarelli, Fabio

    2012-01-01

    At the end of May, 17 scientists involved in an EU COST Action on Conservation Physiology of Marine Fishes met in Oristano, Sardinia, to discuss how physiology can be better used in modelling tools to aid in management of marine ecosystems. Current modelling approaches incorporate physiology...

  2. Differential Geometry

    CERN Document Server

    Stoker, J J

    2011-01-01

    This classic work is now available in an unabridged paperback edition. Stoker makes this fertile branch of mathematics accessible to the nonspecialist by the use of three different notations: vector algebra and calculus, tensor calculus, and the notation devised by Cartan, which employs invariant differential forms as elements in an algebra due to Grassman, combined with an operation called exterior differentiation. Assumed are a passing acquaintance with linear algebra and the basic elements of analysis.

  3. Starting physiology: bioelectrogenesis.

    Science.gov (United States)

    Baptista, Vander

    2015-12-01

    From a Cartesian perspective of rational analysis, the electric potential difference across the cell membrane is one of the fundamental concepts for the study of physiology. Unfortunately, undergraduate students often struggle to understand the genesis of this energy gradient, which makes the teaching activity a hard task for the instructor. The topic of bioelectrogenesis encompasses multidisciplinary concepts, involves several mechanisms, and is a dynamic process, i.e., it never turns off during the lifetime of the cell. Therefore, to improve the transmission and acquisition of knowledge in this field, I present an alternative didactic model. The design of the model assumes that it is possible to build, in a series of sequential steps, an assembly of proteins within the membrane of an isolated cell in a simulated electrophysiology experiment. Initially, no proteins are inserted in the membrane and the cell is at a baseline energy state; the extracellular and intracellular fluids are at thermodynamic equilibrium. Students are guided through a sequence of four steps that add key membrane transport proteins to the model cell. The model is simple at the start and becomes progressively more complex, finally producing transmembrane chemical and electrical gradients. I believe that this didactic approach helps instructors with a more efficient tool for the teaching of the mechanisms of resting membrane potential while helping students avoid common difficulties that may be encountered when learning this topic. Copyright © 2015 The American Physiological Society.

  4. Anxiety sensitivity predicts increased perceived exertion during a 1-mile walk test among treatment-seeking smokers.

    Science.gov (United States)

    Farris, Samantha G; Uebelacker, Lisa A; Brown, Richard A; Price, Lawrence H; Desaulniers, Julie; Abrantes, Ana M

    2017-12-01

    Smoking increases risk of early morbidity and mortality, and risk is compounded by physical inactivity. Anxiety sensitivity (fear of anxiety-relevant somatic sensations) is a cognitive factor that may amplify the subjective experience of exertion (effort) during exercise, subsequently resulting in lower engagement in physical activity. We examined the effect of anxiety sensitivity on ratings of perceived exertion (RPE) and physiological arousal (heart rate) during a bout of exercise among low-active treatment-seeking smokers. Adult daily smokers (n = 157; M age  = 44.9, SD = 11.13; 69.4% female) completed the Rockport 1.0 mile submaximal treadmill walk test. RPE and heart rate were assessed during the walk test. Multi-level modeling was used to examine the interactive effect of anxiety sensitivity × time on RPE and on heart rate at five time points during the walk test. There were significant linear and cubic time × anxiety sensitivity effects for RPE. High anxiety sensitivity was associated with greater initial increases in RPE during the walk test, with stabilized ratings towards the last 5 min, whereas low anxiety sensitivity was associated with lower initial increase in RPE which stabilized more quickly. The linear time × anxiety sensitivity effect for heart rate was not significant. Anxiety sensitivity is associated with increasing RPE during moderate-intensity exercise. Persistently rising RPE observed for smokers with high anxiety sensitivity may contribute to the negative experience of exercise, resulting in early termination of bouts of prolonged activity and/or decreased likelihood of future engagement in physical activity.

  5. Differential control of respiratory frequency and tidal volume during high-intensity interval training.

    Science.gov (United States)

    Nicolò, Andrea; Marcora, Samuele M; Bazzucchi, Ilenia; Sacchetti, Massimo

    2017-08-01

    perceived exertion were dissociated from VT , carbon dioxide output and oxygen uptake responses. Overall, the rating of perceived exertion was strongly correlated with fR (r = 0.87; P < 0.001) but not with VT . These findings may reveal a differential control of fR and VT during HIIT, with fast inputs appearing to contribute more than metabolic stimuli to fR regulation. Differentiating between fR and VT may help to unravel the mechanisms underlying exercise hyperpnoea. © 2017 The Authors. Experimental Physiology © 2017 The Physiological Society.

  6. Differential Growth Responses of Marine Phytoplankton to Herbicide Glyphosate

    Science.gov (United States)

    Wang, Cong; Lin, Xin; Li, Ling; Lin, Senjie

    2016-01-01

    Glyphosate is a globally popular herbicide to kill weeds and its wide applications may lead to accumulation in coastal oceans as a source of phosphorus (P) nutrient or growth inhibitor of phytoplankton. We studied the physiological effects of glyphosate on fourteen species representing five major coastal phytoplankton phyla (haptophyta, bacillariophyta, dinoflagellata, raphidophyta, and chlorophyta). Based on growth responses to different concentrations of glyphosate under contrasting dissolved inorganic phosphorus (DIP) conditions, we found that phytoplankton species could be classified into five groups. Group I (Emiliania huxleyi, Skeletonema costatum, Phaeodactylum tricornutum) could utilize glyphosate as sole P-source to support growth in axenic culture, but in the presence of DIP, they were inhibited by both 36-μM and 360-μM glyphosate. Group II (Karenia mikimotoi, Prorocentrum minimum, Dunaliella tertiolecta, Symbiodinium sp., Heterosigma akashiwo and Alexandrium catenella) could not utilize glyphosate as sole P-source to support growth, and in the presence of DIP growth was not affected by 36-μM but inhibited by 360-μM glyphosate. Glyphosate consistently enhanced growth of Group III (Isochrysis galbana) and inhibited Group IV (Thalassiosira weissflogii, Thalassiosira pseudonana and Chattonella marina) regardless of DIP condition. Group V (Amphidinium carterae) exhibited no measurable response to glyphosate regardless of DIP condition. This grouping is not congruent with the phylogenetic relationships of the phytoplankton species suggesting functional differentiation driven by environmental pressure. We conclude that glyphosate could be used as P-source by some species while is toxic to some other species and yet has no effects on others. The observed differential effects suggest that the continued use of glyphosate and increasing concentration of this herbicide in the coastal waters will likely exert significant impact on coastal marine phytoplankton

  7. Effect of extremely weak pulsed magnetic field type Bemer 3000 on ratings of perceived exertion

    National Research Council Canada - National Science Library

    D Gazurek; K Spodaryk

    2008-01-01

    The aim of this study was to examine whether is an influence of the exposition on different inductions of magnetic fields on rating of perceived exertion during 10 min long standardised physical cycloergometer exercise...

  8. Identification of the lactate threshold and the heart rate deflection point by the perceived exertion curve

    National Research Council Canada - National Science Library

    Conde, Juan Henrique Szymczak; Rubio, Tiago Burigo Guimaraes; Ferreira, Guilherme Assungao; Coelho, Rogerio Luz; de Oliveira, Fernando Roberto; Osiecki, Raul

    2014-01-01

    Conde JHS, Rubio TBG, Ferreira GA, Luz Coelho R, De Oliveira FR, Osiecki R. Identification of the Lactate Threshold and the Heart Rate Deflection Point by the Perceived Exertion Curve. JEPonline 2014;17(3):32-38...

  9. Stiffness and thickness of fascia do not explain chronic exertional compartment syndrome

    DEFF Research Database (Denmark)

    Dahl, Morten; Hansen, Philip; Stål, Per

    2011-01-01

    Chronic exertional compartment syndrome is diagnosed based on symptoms and elevated intramuscular pressure and often is treated with fasciotomy. However, what contributes to the increased intramuscular pressure remains unknown....

  10. Exertional heat stroke management strategies in United States high school football.

    Science.gov (United States)

    Kerr, Zachary Y; Marshall, Stephen W; Comstock, R Dawn; Casa, Douglas J

    2014-01-01

    The 5-year period of 2005-2009 saw more exertional heat stroke-related deaths in organized sports than any other 5-year period in the past 35 years. The risk of exertional heat stroke appears highest in football, particularly during the preseason. To estimate the incidence of exertional heat stroke events and assess the utilization of exertional heat stroke management strategies during the 2011 preseason in United States high school football programs. Cross-sectional study; Level of evidence, 3. A self-administered online questionnaire addressing the incidence of exertional heat stroke events and utilization of exertional heat stroke management strategies (eg, removing athlete's football equipment, calling Emergency Medical Services [EMS]) was completed in May to June 2012 by 1142 (18.0%) athletic trainers providing care to high school football athletes during the 2011 preseason. Among all respondents, 20.3% reported treating at least 1 exertional heat stroke event. An average of 0.50 ± 1.37 preseason exertional heat stroke events were treated per program. Athletic trainers responding to exertional heat stroke reported using an average of 6.6 ± 1.8 management strategies. The most common management strategies were low-level therapeutic interventions such as removing the athlete's football equipment (98.2%) and clothing (77.8%) and moving the athlete to a shaded area (91.6%). Few athletic trainers reported active management strategies such as calling EMS (29.3%) or using a rectal thermometer to check core body temperature (0.9%). Athletic trainers in states with mandated preseason heat acclimatization guidelines reported a higher utilization of management strategies such as cooling the athlete through air conditioning (90.1% vs 65.0%, respectively; P fans (54.3% vs 42.0%, respectively; P = .06) and monitoring the athlete's temperature (60.5% vs 46.2%, respectively; P = .04). Preseason exertional heat stroke events, which are likely to be fatal if untreated, were

  11. Exertional rhabdomyolysis following excessive exercise of university freshman cheer-training.

    Science.gov (United States)

    Mahakkanukrauh, Ajanee; Sangchan, Apichat; Mootsikapun, Piroon

    2003-08-01

    Exertional rhabdomyolysis is a life threatening condition resulting from lysis of muscle cells after vigorous exercise. It can cause many complications such as renal failure. It occurs most commonly in military personnel but also in civilians who have excessive excercise after work. Two cases of freshmen who had exertional rhabdomyolysis were reported to illustrate the potential risk of cheer-training. Appropriate measures should be arranged to prevent this condition. Diagnosis and treatment should be given promptly to prevent serious complications.

  12. Physical exercise at the workplace reduces perceived physical exertion during healthcare work: cluster randomized controlled trial.

    Science.gov (United States)

    Jakobsen, Markus Due; Sundstrup, Emil; Brandt, Mikkel; Jay, Kenneth; Aagaard, Per; Andersen, Lars L

    2015-11-01

    High physical exertion during work is a risk factor for musculoskeletal pain and long-term sickness absence. Physical exertion (RPE) reflects the balance between physical work demands and physical capacity of the individual. Thus, increasing the physical capacity through physical exercise may decrease physical exertion during work. This study investigates the effect of workplace-based versus home-based physical exercise on physical exertion during work (WRPE) among healthcare workers. 200 female healthcare workers (age: 42.0, body mass index: 24.1, average pain intensity: 3.1 on a scale of 0 to 10, average WRPE: 3.6 on a scale of 0 to 10) from 18 departments at three participating hospitals. Participants were randomly allocated at the cluster level to 10 weeks of: (1) workplace physical exercise (WORK) performed in groups during working hours for 5×10 minutes per week and up to five group-based coaching sessions on motivation for regular physical exercise, or (2) home-based physical exercise (HOME) performed during leisure time for 5×10 minutes per week. Physical exertion was assessed at baseline and at 10-week follow-up. 2.2 (SD: 1.1) and 1.0 (SD: 1.2) training sessions were performed per week in WORK and HOME, respectively. Physical exertion was reduced more in WORK than HOME (pgroup differences in physical exertion at follow-up (WORK vs. HOME) was -0.5 points (95% CI -0.8 to -0.2). Within-group effect size (Cohen's d) in WORK and HOME was 0.43 and 0.13, respectively. Physical exercise performed at the workplace appears more effective than home-based exercise in reducing physical exertion during daily work tasks in healthcare workers. © 2015 the Nordic Societies of Public Health.

  13. Typhoons exert significant but differential impact on net carbon ecosystem exchange of subtropical mangrove ecosystems in China

    Science.gov (United States)

    Chen, H.; Lu, W.; Yan, G.; Yang, S.; Lin, G.

    2014-06-01

    Typhoons are very unpredictable natural disturbances to subtropical mangrove forests in Asian countries, but litter information is available on how these disturbances affect ecosystem level carbon dioxide (CO2) exchange of mangrove wetlands. In this study, we examined short-term effect of frequent strong typhoons on defoliation and net ecosystem CO2 exchange (NEE) of subtropical mangroves, and also synthesized 19 typhoons during a 4-year period between 2009 and 2012 to further investigate the regulation mechanisms of typhoons on ecosystem carbon and water fluxes following typhoon disturbances. Strong wind and intensive rainfall caused defoliation and local cooling effect during typhoon season. Daily total NEE values were decreased by 26-50% following some typhoons (e.g. W28-Nockten, W35-Molave and W35-Lio-Fan), but were significantly increased (43-131%) following typhoon W23-Babj and W38-Megi. The magnitudes and trends of daily NEE responses were highly variable following different typhoons, which were determined by the balance between the variances of gross ecosystem production (GEP) and ecosystem respiration (RE). Furthermore, results from our synthesis indicated that the landfall time of typhoon, wind speed and rainfall were the most important factors controlling the CO2 fluxes following typhoon events. These findings not only indicate that mangrove ecosystems have strong resilience to the frequent typhoon disturbances, but also demonstrate the damage of increasing typhoon intensity and frequency on subtropical mangrove ecosystems under future global climate change scenarios.

  14. A bibliometric analysis of exertional heat stroke research in Web of Science.

    Science.gov (United States)

    Mao, Zhi; Liu, Chao; Chen, Shuo; Zhu, Zheng-Guo; Kang, Hong-Jun; Zhou, Fei-Hu

    2016-01-01

    Exertional heat stroke is a fatal condition and remains a health problem. This paper evaluates the publication trend regarding exertional heat stroke research between 1996 and 2015 using a bibliometric method. Articles regarding exertional heat stroke research published between 1996 and December 2015 were searched for in the SCI-EXPANDED database of Web of Science. The search results were analyzed with regard to publication year; publication quantity regarding countries/regions, and authors; citation frequency; and journal distribution. CiteSpace (v3.6) was used for a document co-citation visualization analysis. In total, 289 publications on heat stroke were located. After selection, 209 original articles conducted across 28 countries/regions and published in 83 journals were included in the analysis. The USA, Isreal, and France were the most common locations for exertional heat stroke studies. The CiteSpace visualization cluster analysis showed that exertional heat stroke-related mortality and protective measures were constant concerns of research. Research related to exertional heat stroke has been continuous concerned. USA is still the leading country in this field.

  15. Perceived exertion at work in women with fibromyalgia: explanatory factors and comparison with healthy women.

    Science.gov (United States)

    Palstam, Annie; Larsson, Anette; Bjersing, Jan; Löfgren, Monika; Ernberg, Malin; Bileviciute-Ljungar, Indre; Ghafouri, Bijar; Sjörs, Anna; Larsson, Britt; Gerdle, Björn; Kosek, Eva; Mannerkorpi, Kaisa

    2014-09-01

    To investigate perceived exertion at work in women with fibromyalgia. A controlled cross-sectional multi-centre study. Seventy-three women with fibromyalgia and 73 healthy women matched by occupation and physical workload were compared in terms of perceived exertion at work (0-14), muscle strength, 6-min walk test, symptoms rated by Fibromyalgia Impact Questionnaire (FIQ), work status (25-100%), fear avoidance work beliefs (0-42), physical activity at work (7-21) and physical workload (1-5). Spearman's correlation coefficient and linear regression analysis were conducted. Perceived exertion at work was significantly higher in the fibromyalgia group than in the reference group (p = 0.002), while physical activity at work did not differ between the groups. Physical capacity was lower and symptom severity higher in fibromyalgia compared with references (p fibromyalgia, perceived exertion at work showed moderate correlation with physical activity at work, physical workload and fear avoidance work beliefs (rs = 0.53-0.65, p anxiety (rs = 0.26, p = 0.027). Regression analysis indicated that the physical activity at work and fear avoidance work beliefs explained 50% of the perceived exertion at work. Women with fibromyalgia perceive an elevated exertion at work, which is associated with physical work-related factors and factors related to fear and anxiety.

  16. High self-perceived exercise exertion before bedtime is associated with greater objectively assessed sleep efficiency.

    Science.gov (United States)

    Brand, Serge; Kalak, Nadeem; Gerber, Markus; Kirov, Roumen; Pühse, Uwe; Holsboer-Trachsler, Edith

    2014-09-01

    To assess the association between self-perceived exercise exertion before bedtime and objectively measured sleep. Fifty-two regularly exercising young adults (mean age, 19.70 years; 54% females) underwent sleep electroencephalographic recordings 1.5 h after completing moderate to vigorous exercise in the evening. Before sleeping, participants answered questions regarding degree of exertion of the exercise undertaken. Greater self-perceived exertion before bedtime was associated with higher objectively assessed sleep efficiency (r = 0.69, P exercise exertion was associated with more deep sleep, shortened sleep onset time, fewer awakenings after sleep onset, and shorter wake duration after sleep onset. Multiple linear regression analysis showed that objective sleep efficiency was predicted by increased exercise exertion, shortened sleep onset time, increased deep sleep, and decreased light sleep. Against expectations and general recommendations for sleep hygiene, high self-perceived exercise exertion before bedtime was associated with better sleep patterns in a sample of healthy young adults. Further studies should also focus on elderly adults and adults suffering from insomnia. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Assessment of decision-making performance and in-game physical exertion of Australian football umpires.

    Science.gov (United States)

    Larkin, Paul; O'Brien, Brendan; Mesagno, Christopher; Berry, Jason; Harvey, Jack; Spittle, Michael

    2014-01-01

    The aim of this study is to investigate the effects of in-game physical exertion on decision-making performance of Australian football umpires. Fifteen Australian football umpires (Mage = 36, s = 13.5 years; Mgames umpired = 235.2, s = 151.3) volunteered to participate in the study. During five competitive Australian football pre-season games, measures of in-game physical exertion (blood lactate levels, global positioning system [GPS]) and decision-making performance (video-based test) were obtained. There were no significant correlations between physical exertion in a particular quarter and decision-making performance in either the same quarter or any other quarter. Video-based decision-making performance was effected by time in game χ(2)(3) = 24.24, P = 0.001, with Quarter 4 performance significantly better than both Quarter 2 and Quarter 3. In-game physical exertion (blood lactate) significantly decreased over the course of the game χ(2)(3) = 11.58, P = 0.009. Results indicate no definable link between in-game physical exertion and decision-making performance. It is, however, presumed that decision-making performance may be affected by the time or context of the game. Future research is warranted to explore the relationship between physical exertion and decision-making performance to potentially inform Australian football umpire training programmes that replicate in-game physical and decision-making demands.

  18. Single Cell Physiology

    Science.gov (United States)

    Neveu, Pierre; Sinha, Deepak Kumar; Kettunen, Petronella; Vriz, Sophie; Jullien, Ludovic; Bensimon, David

    The possibility to control at specific times and specific places the activity of biomolecules (enzymes, transcription factors, RNA, hormones, etc.) is opening up new opportunities in the study of physiological processes at the single cell level in a live organism. Most existing gene expression systems allow for tissue specific induction upon feeding the organism with exogenous inducers (e.g., tetracycline). Local genetic control has earlier been achieved by micro-injection of the relevant inducer/repressor molecule, but this is an invasive and possibly traumatic technique. In this chapter, we present the requirements for a noninvasive optical control of the activity of biomolecules and review the recent advances in this new field of research.

  19. The mechanical transduction of physiological strength electric fields.

    Science.gov (United States)

    Hart, Francis X

    2008-09-01

    In this article it is proposed that electric fields of physiological strength (approximately 100 V/m) are transduced by the mechanical torque they exert on glycoproteins. The resulting mechanical signal is then transmitted to the cytoskeleton and propagated throughout the cell interior. This mechanical coupling is analyzed for transmembrane glycoproteins, such as integrins and the glycocalyx, and for glycoproteins in the extracellular matrix of cartilage. The applied torque is opposed by viscous fluid drag and restoring forces exerted by adjacent molecules in the membrane or cartilage. The resulting system represents a damped, driven harmonic oscillator. The amplitude of oscillation is constant at low frequencies, but falls off rapidly in the range 1-1000 Hz. The transition frequency depends on parameters such as the viscosity of the surrounding fluid and the restoring force exerted by the surrounding structure. The amplitude increases as the fourth power of the length of the transmembrane glycoproteins and as the square of the applied field. This process may operate in concert with other transduction mechanisms, such as the opening of voltage-gated channels and electrodiffusion/osmosis for DC fields. Copyright 2008 Wiley-Liss, Inc.

  20. Essential Oil of Pinus koraiensis Exerts Antiobesic and Hypolipidemic Activity via Inhibition of Peroxisome Proliferator-Activated Receptors Gamma Signaling

    Directory of Open Access Journals (Sweden)

    Hyun-Suk Ko

    2013-01-01

    Full Text Available Our group previously reported that essential oil of Pinus koraiensis (EOPK exerts antihyperlipidemic effects via upregulation of low-density lipoprotein receptor and inhibition of acyl-coenzyme A. In the present study, we investigated the antiobesity and hypolipidemic mechanism of EOPK using in vitro 3T3-L1 cells and in vivo HFD-fed rats. EOPK markedly suppressed fat accumulation and intracellular triglyceride associated with downregulation of adipogenic transcription factor expression, including PPARγ and CEBPα in the differentiated 3T3-L1 adipocytes. Additionally, EOPK attenuated the expression levels of FABP and GPDH as target genes of PPARγ during adipocyte differentiation. Furthermore, PPARγ inhibitor GW9662 enhanced the decreased expression of FABP and PPARγ and fat accumulation induced by EOPK. To confirm the in vitro activity of EOPK, animal study was performed by administering normal diet, HFD, and/or EOPK at the dose of 100 or 200 mg/kg for 6 weeks. Consistently, EOPK significantly suppressed body weight gain, serum triglyceride, total cholesterol, LDL cholesterol, and AI value and increased HDL cholesterol in a dose-dependent manner. Immunohistochemistry revealed that EOPK treatment abrogated the expression of PPARγ in the liver tissue sections of EOPK-treated rats. Taken together, our findings suggest that EOPK has the antiobesic and hypolipidemic potential via inhibition of PPARγ-related signaling.

  1. Physiology for engineers applying engineering methods to physiological systems

    CERN Document Server

    Chappell, Michael

    2016-01-01

    This book provides an introduction to qualitative and quantitative aspects of human physiology. It looks at biological and physiological processes and phenomena, including a selection of mathematical models, showing how physiological problems can be mathematically formulated and studied. It also illustrates how a wide range of engineering and physics topics, including electronics, fluid dynamics, solid mechanics and control theory can be used to describe and understand physiological processes and systems. Throughout the text there are introductions to measuring and quantifying physiological processes using both signal and imaging technologies. Physiology for Engineers describes the basic structure and models of cellular systems, the structure and function of the cardiovascular system, the electrical and mechanical activity of the heart and provides an overview of the structure and function of the respiratory and nervous systems. It also includes an introduction to the basic concepts and applications of reacti...

  2. Differential geometry

    CERN Document Server

    Guggenheimer, Heinrich W

    1977-01-01

    This is a text of local differential geometry considered as an application of advanced calculus and linear algebra. The discussion is designed for advanced undergraduate or beginning graduate study, and presumes of readers only a fair knowledge of matrix algebra and of advanced calculus of functions of several real variables. The author, who is a Professor of Mathematics at the Polytechnic Institute of New York, begins with a discussion of plane geometry and then treats the local theory of Lie groups and transformation groups, solid differential geometry, and Riemannian geometry, leading to a

  3. Differential geometry

    CERN Document Server

    Graustein, William C

    2006-01-01

    This first course in differential geometry presents the fundamentals of the metric differential geometry of curves and surfaces in a Euclidean space of three dimensions. Written by an outstanding teacher and mathematician, it explains the material in the most effective way, using vector notation and technique. It also provides an introduction to the study of Riemannian geometry.Suitable for advanced undergraduates and graduate students, the text presupposes a knowledge of calculus. The first nine chapters focus on the theory, treating the basic properties of curves and surfaces, the mapping of

  4. Regulating plant physiology with organic electronics.

    Science.gov (United States)

    Poxson, David J; Karady, Michal; Gabrielsson, Roger; Alkattan, Aziz Y; Gustavsson, Anna; Doyle, Siamsa M; Robert, Stéphanie; Ljung, Karin; Grebe, Markus; Simon, Daniel T; Berggren, Magnus

    2017-05-02

    The organic electronic ion pump (OEIP) provides flow-free and accurate delivery of small signaling compounds at high spatiotemporal resolution. To date, the application of OEIPs has been limited to delivery of nonaromatic molecules to mammalian systems, particularly for neuroscience applications. However, many long-standing questions in plant biology remain unanswered due to a lack of technology that precisely delivers plant hormones, based on cyclic alkanes or aromatic structures, to regulate plant physiology. Here, we report the employment of OEIPs for the delivery of the plant hormone auxin to induce differential concentration gradients and modulate plant physiology. We fabricated OEIP devices based on a synthesized dendritic polyelectrolyte that enables electrophoretic transport of aromatic substances. Delivery of auxin to transgenic Arabidopsis thaliana seedlings in vivo was monitored in real time via dynamic fluorescent auxin-response reporters and induced physiological responses in roots. Our results provide a starting point for technologies enabling direct, rapid, and dynamic electronic interaction with the biochemical regulation systems of plants.

  5. Life starts at home: bathing, exertion and participation for people with mobility impairment.

    Science.gov (United States)

    Greiman, Lillie; Fleming, S Parker; Ward, Bryce; Myers, Andrew; Ravesloot, Craig

    2018-01-03

    Investigate the relationship between perceived exertion while bathing/dressing/grooming and associations with social -recreational activities outside the home for individuals with mobility impairment (MI). We use a two-study approach examining data from the American Time Use Survey (ATUS) and primary data from the Health and Home Survey (HHS). We explore the relationship between bathing/dressing/grooming and engagement in social-recreational activities and the role that exertion in the bathroom may play in participation in these activities. General community setting. For the ATUS survey, participants include 6,002 individuals who report a MI. For the HHS we used two mail based recruitment methods to recruit a sample of 170 individuals with MI across three geographically diverse U.S. communities. Participation in social and recreational activities. We show that people with MI (relative to those without MI) are less likely to report spending any time bathing/dressing/grooming on a given day, but spend more time when they do. People with MI report higher exertion while bathing/dressing/grooming than people without. People with MI are less likely to leave the house or engage in social-recreational activities on days where they do not engage in bathing activities. People who report greater exertion in the bathroom engage in fewer social- recreational activities. Exertion in the bathroom may present a barrier to participation indicating a relationship between exertion in the bathroom and social-recreational participation. Research that examines the impact of home modifications on exertion and participation is needed. Copyright © 2018. Published by Elsevier Inc.

  6. Differential equations

    CERN Document Server

    Hochstadt, Harry

    2012-01-01

    Modern approach to differential equations presents subject in terms of ideas and concepts rather than special cases and tricks which traditional courses emphasized. No prerequisites needed other than a good calculus course. Certain concepts from linear algebra used throughout. Problem section at end of each chapter.

  7. Differential belongings

    DEFF Research Database (Denmark)

    Oldrup, Helene

    2014-01-01

    This paper explores suburban middle-class residents’ narratives about housing choice, everyday life and belonging in residential areas of Greater Copenhagen, Denmark, to understand how residential processes of social differentiation are constituted. Using Savage et al.’s concepts of discursive re...

  8. Ventilatory physiology of children and adolescents with anxiety disorders.

    Science.gov (United States)

    Pine, D S; Coplan, J D; Papp, L A; Klein, R G; Martinez, J M; Kovalenko, P; Tancer, N; Moreau, D; Dummit, E S; Shaffer, D; Klein, D F; Gorman, J M

    1998-02-01

    Abnormalities in ventilatory physiology have been noted in adults with panic disorder. We tested the hypothesis that abnormalities in ventilatory physiology differentiate children and adolescents with anxiety disorders from psychiatrically healthy children. Ventilatory physiology was monitored with a canopy apparatus during room-air breathing and 15 minutes of carbon dioxide exposure in 33 children and adolescents comprising 18 probands with an anxiety disorder and 15 psychiatrically healthy children. During room-air breathing, probands had significantly larger minute ventilation, larger tidal volumes, and more variable breathing patterns than healthy comparisons, but the groups did not differ in end-tidal carbon dioxide or respiratory rate. During carbon dioxide challenge, probands exhibited larger minute ventilation and respiratory rate responses relative to comparisons. These findings on the association between ventilatory physiology and anxiety disorders in children and adolescents are consistent with results from studies of adults with panic disorder.

  9. Supraphysiological Doses of Performance Enhancing Anabolic-Androgenic Steroids Exert Direct Toxic Effects on Neuron-like Cells

    Directory of Open Access Journals (Sweden)

    John Robert Basile

    2013-05-01

    Full Text Available Anabolic-androgenic steroids (AAS are lipophilic hormones often taken in excessive quantities by athletes and bodybuilders to enhance performance and increase muscle mass. AAS exert well known toxic effects on specific cell and tissue types and organ systems. The attention that androgen abuse has received lately should be used as an opportunity to educate both athletes and the general population regarding their adverse effects. Among numerous commercially available steroid hormones, very few have been specifically tested for direct neurotoxicity. We evaluated the effects of supraphysiological doses of methandienone and 17-α-methyltestosterone on sympathetic-like neuron cells. Vitality and apoptotic effects were analyzed, and immunofluorescence staining and western blot performed. In this study, we demonstrate that exposure of supraphysiological doses of methandienone and 17-α-methyltestosterone are toxic to the neuron-like differentiated pheochromocytoma cell line PC12, as confirmed by toxicity on neurite networks responding to nerve growth factor and the modulation of the survival and apoptosis-related proteins ERK, caspase-3, poly (ADP-ribose polymerase and heat-shock protein 90. We observe, in contrast to some previous reports but in accordance with others, expression of the androgen receptor (AR in neuron-like cells, which when inhibited mitigated the toxic effects of AAS tested, suggesting that the AR could be binding these steroid hormones to induce genomic effects. We also note elevated transcription of neuritin in treated cells, a neurotropic factor likely expressed in an attempt to resist neurotoxicity. Taken together, these results demonstrate that supraphysiological exposure to the AAS methandienone and 17-α-methyltestosterone exert neurotoxic effects by an increase in the activity of the intrinsic apoptotic pathway and alterations in neurite networks.

  10. Supraphysiological doses of performance enhancing anabolic-androgenic steroids exert direct toxic effects on neuron-like cells.

    Science.gov (United States)

    Basile, John R; Binmadi, Nada O; Zhou, Hua; Yang, Ying-Hua; Paoli, Antonio; Proia, Patrizia

    2013-01-01

    Anabolic-androgenic steroids (AAS) are lipophilic hormones often taken in excessive quantities by athletes and bodybuilders to enhance performance and increase muscle mass. AAS exert well known toxic effects on specific cell and tissue types and organ systems. The attention that androgen abuse has received lately should be used as an opportunity to educate both athletes and the general population regarding their adverse effects. Among numerous commercially available steroid hormones, very few have been specifically tested for direct neurotoxicity. We evaluated the effects of supraphysiological doses of methandienone and 17-α-methyltestosterone on sympathetic-like neuron cells. Vitality and apoptotic effects were analyzed, and immunofluorescence staining and western blot performed. In this study, we demonstrate that exposure of supraphysiological doses of methandienone and 17-α-methyltestosterone are toxic to the neuron-like differentiated pheochromocytoma cell line PC12, as confirmed by toxicity on neurite networks responding to nerve growth factor and the modulation of the survival and apoptosis-related proteins ERK, caspase-3, poly (ADP-ribose) polymerase and heat-shock protein 90. We observe, in contrast to some previous reports but in accordance with others, expression of the androgen receptor (AR) in neuron-like cells, which when inhibited mitigated the toxic effects of AAS tested, suggesting that the AR could be binding these steroid hormones to induce genomic effects. We also note elevated transcription of neuritin in treated cells, a neurotropic factor likely expressed in an attempt to resist neurotoxicity. Taken together, these results demonstrate that supraphysiological exposure to the AAS methandienone and 17-α-methyltestosterone exert neurotoxic effects by an increase in the activity of the intrinsic apoptotic pathway and alterations in neurite networks.

  11. Procedures of Exercise Physiology Laboratories

    Science.gov (United States)

    Bishop, Phillip A.; Fortney, Suzanne; Greenisen, Michael; Siconolfi, Steven F.; Bamman, Marcas M.; Moore, Alan D., Jr.; Squires, William

    1998-01-01

    This manual describes the laboratory methods used to collect flight crew physiological performance data at the Johnson Space Center. The Exercise Countermeasures Project Laboratory is a standard physiology laboratory; only the application to the study of human physiological adaptations to spaceflight is unique. In the absence of any other recently published laboratory manual, this manual should be a useful document staffs and students of other laboratories.

  12. Physiology Considerations in Geriatric Patients.

    Science.gov (United States)

    Alvis, Bret D; Hughes, Christopher G

    2015-09-01

    Physiology changes at the structural, functional, and molecular levels as people age, and every major organ system experiences physiologic change with time. The changes to the nervous system result mostly in cognitive impairments, the cardiovascular system develops higher blood pressures with lower cardiac output, the respiratory system undergoes a reduction of arterial oxyhemoglobin levels, the gastrointestinal system experiences delayed gastric emptying and reduction of hepatic metabolism, and the renal system experiences a diminished glomerular filtration rate. Combined, these changes create a complex physiologic condition. This unique physiology must be taken into consideration for geriatric patients undergoing general anesthesia. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Hemorrhagic shock: The "physiology approach"

    Directory of Open Access Journals (Sweden)

    Fabrizio Giuseppe Bonanno

    2012-01-01

    Full Text Available A shift of approach from ′clinics trying to fit physiology′ to the one of ′physiology to clinics′, with interpretation of the clinical phenomena from their physiological bases to the tip of the clinical iceberg, and a management exclusively based on modulation of physiology, is finally surging as the safest and most efficacious philosophy in hemorrhagic shock. ATLS® classification and recommendations on hemorrhagic shock are not helpful because antiphysiological and potentially misleading. Hemorrhagic shock needs to be reclassified in the direction of usefulness and timing of intervention: in particular its assessment and management need to be tailored to physiology.

  14. Brain Physiology: Research and Theory.

    Science.gov (United States)

    Esler, William K.

    1982-01-01

    Indicates how research about the physiology and chemistry of the brain verifies the educational applications of Piaget's theory. Discusses maturation, experience, social transmission, and equilibration. (Author/DC)

  15. Egg activation in physiological polyspermy

    National Research Council Canada - National Science Library

    Iwao, Yasuhiro

    2012-01-01

    .... While most animals exhibit monospermy, which is ensured by polyspermy blocks to prevent the entry of extra sperm into the egg at fertilization, several animals exhibit physiological polyspermy...

  16. Polyamines in plant physiology

    Science.gov (United States)

    Galston, A. W.; Sawhney, R. K.

    1990-01-01

    The diamine putrescine, the triamine spermidine, and the tetramine spermine are ubiquitous in plant cells, while other polyamines are of more limited occurrence. Their chemistry and pathways of biosynthesis and metabolism are well characterized. They occur in the free form as cations, but are often conjugated to small molecules like phenolic acids and also to various macromolecules. Their titer varies from approximately micromolar to more than millimolar, and depends greatly on environmental conditions, especially stress. In cereals, the activity of one of the major polyamine biosynthetic enzymes, arginine decarboxylase, is rapidly and dramatically increased by almost every studied external stress, leading to 50-fold or greater increases in putrescine titer within a few hours. The physiological significance of this increase is not yet clear, although most recent work suggests an adaptive, protective role. Polyamines produced through the action of ornithine decarboxylase, by contrast, seem essential for DNA replication and cell division. The application of exogenous polyamines produces effects on patterns of senescence and morphogenesis, suggesting but not proving a regulatory role for polyamines in these processes. The evidence for such a regulatory role is growing.

  17. Physiology in Modelica

    Directory of Open Access Journals (Sweden)

    Marek Mateják

    2014-05-01

    Full Text Available Modelica is an object-oriented language, in which models can be created and graphically represented by connecting instances of classes from libraries. These connections are not only assignments of values; they can also represent acausal equality. Even more, they can model Kirchhoff’s laws of circuits. In Modelica it is possible to develop library classes which are an analogy of electrical circuit components. The result of our work in this field is Physiolibrary (www.physiolibrary.org – a free, open-source Modelica library for human physiology. By graphical joining instances of Physiolibrary classes, user can create models of cardiovascular circulation, thermoregulation, metabolic processes, nutrient distribution, gas transport, electrolyte regulation, water distribution, hormonal regulation and pharmacological regulation. After simple setting of the parameters, the models are ready to simulate. After simulation, the user can examine variables as their values change over time. Representing the model as a diagram has also great educational advantages, because students are able to better understand physical principles when they see them modeled graphically.

  18. Dimorfismo sexual en el acebo, Ilex aquifolium: ¿coste de la reproducción, selección sexual o diferenciación fisiológica? Sexual dimorphism in holly Ilex aquifolium: cost of reproduction, sexual selection or physiological differentiation?

    Directory of Open Access Journals (Sweden)

    JOSÉ RAMÓN OBESO

    2002-03-01

    (Aquifoliaceae: cost of reproduction, sexual selection (pollen competition and physiological differentiation between sexes. Here we present both published and new experimental and observational results. At flowering, males allocated more in reproduction than females; however at fruiting females allocated about ten times more in terms of carbon and about five times more in terms of nitrogen than males. Both sexes did not differ in leaf dynamics. Branch RGR usually showed greater values in male branches, but the results depended on the ecological context. Tree growth rate, estimated from mean width of annual rings over 10-30 yr, was significantly higher for males. Experimental debbuding in reproductive branches of females accounted for an increase in RGR compared to branches that matured fruits. When competition among males was examined, there were significant differences among male trees in pollen production per flower. The experimental crossing of five males and five females demonstrated strong maternal effects on fecundity, while non significant differences among males were found in their probability of sire progeny. There were some physiological differences between sexes. The efficiency of photosynthesis of leaves (measured as Fv' / Fm' on nonfruiting branches of females was higher than for leaves on branches of male trees under low-light conditions. On the other side, the water-use efficiency, measured by carbon isotope discrimination, was greater in males under xeric conditions. These results are used to discuss the importance of the above mentioned hypothesis

  19. Teaching Cardiovascular Physiology with Equivalent Electronic Circuits in a Practically Oriented Teaching Module

    Science.gov (United States)

    Ribaric, Samo; Kordas, Marjan

    2011-01-01

    Here, we report on a new tool for teaching cardiovascular physiology and pathophysiology that promotes qualitative as well as quantitative thinking about time-dependent physiological phenomena. Quantification of steady and presteady-state (transient) cardiovascular phenomena is traditionally done by differential equations, but this is time…

  20. Exertion Fatigue and Chronic Fatigue Are Two Distinct Constructs in People Post-Stroke

    Science.gov (United States)

    Tseng, Benjamin Y.; Billinger, Sandra A.; Gajewski, Byron J.; Kluding, Patricia M.

    2013-01-01

    Background and Purpose Post-stroke fatigue is a common and neglected issue despite the fact that it impacts daily functions, quality of life, and has been linked with a higher mortality rate because of its association with a sedentary lifestyle. The purpose of this study was to identify the contributing factors of exertion fatigue and chronic fatigue in people post-stroke. Methods Twenty-one post-stroke people (12 males, 9 females; 59.5±10.3 years of age; time after stroke 4.1±3.5 years) participated in the study. The response variables included exertion fatigue and chronic fatigue. Participants underwent a standardized fatigue-inducing exercise on a recumbent stepper. Exertion fatigue level was assessed at rest and immediately after exercise using the Visual Analog Fatigue Scale. Chronic fatigue was measured by the Fatigue Severity Scale. The explanatory variables included aerobic fitness, motor control, and depressive symptoms measured by peak oxygen uptake, Fugl-Meyer motor score, and the Geriatric Depression Scale, respectively. Results Using forward stepwise regression, we found that peak oxygen uptake was an independent predictor of exertion fatigue (P=0.006), whereas depression was an independent predictor of chronic fatigue (P=0.002). Conclusion Exertion fatigue and chronic fatigue are 2 distinct fatigue constructs, as identified by 2 different contributing factors. PMID:20947841

  1. The Influence of Exercise Environment and Gender on Mood and Exertion.

    Science.gov (United States)

    Plante, Thomas G; Oppezzo, Marily A; Diaz, L Aislinn; Pistoresi, Selena; Santos, Michael; Fahey, Jacqueline E; Kay, Elizabeth; Britton, Briana; Khan, Suheel

    This study examined the influence of exercise environment and gender on post-exercise mood and exertion. College student participants (55 females, 49 males) were instructed to pedal a stationary bike at a moderate pace for 20 minutes. Participants were randomly assigned to one of three laboratory conditions: (1) exercising in front of a mirror and posters showing ideal fit body types (i.e., celebrity male and female personal trainers), (2) exercising in front of a mirror only, or (3) a control condition in which participants exercised without a mirror or posters. The Activation-Deactivation Adjective Check List (AD-ACL), measuring exercise-induced mood states, was administered both before and after exercise. Average bike speed throughout the exercise session measured exertion. Mirrors and posters of ideally fit celebrities did interact with gender on post-exercise tension in that women felt most tense after exercising in front of the mirror and posters while men were most tense after exercising in front of the mirror only. Exercise exertion was also impacted by experimental condition such that participants rode significantly faster in the mirror and posters condition. There was no significant interaction of gender and condition on exercise exertion, but women pedaled fastest in the mirror and poster condition relative to the other conditions. Results suggest that exercise exertion and tension reduction are partially a by-product of gender and exercise environment.

  2. Criterion-related validity of perceived exertion scales in healthy children: a systematic review and meta-analysis.

    Science.gov (United States)

    Rodríguez, Iván; Zambrano, Lysien; Manterola, Carlos

    2016-04-01

    Physiological parameters used to measure exercise intensity are oxygen uptake and heart rate. However, perceived exertion (PE) is a scale that has also been frequently applied. The objective of this study is to establish the criterion-related validity of PE scales in children during an incremental exercise test. Seven electronic databases were used. Studies aimed at assessing criterion-related validity of PE scales in healthy children during an incremental exercise test were included. Correlation coefficients were transformed into z-values and assessed in a meta-analysis by means of a fixed effects model if I2 was below 50% or a random effects model, if it was above 50%. wenty-five articles that studied 1418 children (boys: 49.2%) met the inclusion criteria. Children's average age was 10.5 years old. Exercise modalities included bike, running and stepping exercises. The weighted correlation coefficient was 0.835 (95% confidence interval: 0.762-0.887) and 0.874 (95% confidence interval: 0.794-0.924) for heart rate and oxygen uptake as reference criteria. The production paradigm and scales that had not been adapted to children showed the lowest measurement performance (p valid in healthy children during an incremental exercise test. Child-specific rating scales showed a better performance than those that had not been adapted to this population. Further studies with better methodological quality should be conducted in order to confirm these results. Sociedad Argentina de Pediatría.

  3. The nuclear receptor ROR(alpha) exerts a bi-directional regulation of IL-6 in resting and reactive astrocytes.

    Science.gov (United States)

    Journiac, Nathalie; Jolly, Sarah; Jarvis, Christopher; Gautheron, Vanessa; Rogard, Monique; Trembleau, Alain; Blondeau, Jean-Paul; Mariani, Jean; Vernet-der Garabedian, Béatrice

    2009-12-15

    Astrocytes and one of their products, IL-6, not only support neurons but also mediate inflammation in the brain. Retinoid-related orphan receptor-alpha (RORalpha) transcription factor has related roles, being neuro-protective and, in peripheral tissues, anti-inflammatory. We examined the relation of ROR(alpha) to astrocytes and IL-6 using normal and ROR(alpha) loss-of-function mutant mice. We have shown ROR(alpha) expression in astrocytes and its up-regulation by pro-inflammatory cytokines. We have also demonstrated that ROR(alpha) directly trans-activates the Il-6 gene. We suggest that this direct control is necessary to maintain IL-6 basal level in the brain and may be a link between the neuro-supportive roles of ROR(alpha), IL-6, and astrocytes. Furthermore, after inflammatory stimulation, the absence of ROR(alpha) results in excessive IL-6 up-regulation, indicating that ROR(alpha) exerts an indirect repression probably via the inhibition of the NF-kappaB signaling. Thus, our findings indicate that ROR(alpha) is a pluripotent molecular player in constitutive and adaptive astrocyte physiology.

  4. Bisphenol A Modifies the Regulation Exerted by Testosterone on 5α-Reductase Isozymes in Ventral Prostate of Adult Rats

    Directory of Open Access Journals (Sweden)

    Pilar Sánchez

    2013-01-01

    Full Text Available The development, growth, and function of the prostate gland depend on androgen stimulation. The primary androgen in prostate is 5-dihydrotestosterone (DHT which is synthesized from circulating testosterone (T through the action of 5-reductase (5-R. Although 5-R occurs as five isozymes, only 5-R1 and 5-R2 are physiologically involved in steroidogenesis. The endocrine disruptor bisphenol A (BPA alters sexual organs, including the prostate. Our previous findings indicated that BPA decreased the expression of 5-R1 and 5-R2 in rat prostate but also circulating T. Thus, it is unclear whether BPA exerts this effect on 5-R isozymes by reducing circulating T or by any other mechanism. In this study, we examine the effects of short-term exposure to BPA at doses below 25 g/Kg/d and above 300 g/Kg/d of the TDI on mRNA levels of 5-R1 and 5-R2 in prostate of adult castrated rats supplemented with T to achieve constant circulating T levels. mRNA levels were measured by absolute quantitative RT-PCR, T levels by RIA, and DHT levels by ELISA. Our results indicated that in castrated rats treated with T BPA at the two doses studied significantly decreased the mRNA levels of both 5-R isozymes in a dose-dependent manner without modifications in circulating T.

  5. Neoglucosylated collagen matrices drive neuronal cells to differentiate.

    Science.gov (United States)

    Russo, Laura; Sgambato, Antonella; Lecchi, Marzia; Pastori, Valentina; Raspanti, Mario; Natalello, Antonino; Doglia, Silvia M; Nicotra, Francesco; Cipolla, Laura

    2014-04-16

    Despite the relevance of carbohydrates as cues in eliciting specific biological responses, glycans have been rarely exploited in the study of neuronal physiology. We report thereby the study of the effect of neoglucosylated collagen matrices on neuroblastoma F11 cell line behavior. Morphological and functional analysis clearly showed that neoglucosylated collagen matrices were able to drive cells to differentiate. These data show for the first time that F11 cells can be driven from proliferation to differentiation without the use of chemical differentiating agents. Our work may offer to cell biologists new opportunities to study neuronal cell differentiation mechanisms in a cell environment closer to physiological conditions.

  6. Differential topology

    CERN Document Server

    Margalef-Roig, J

    1992-01-01

    ...there are reasons enough to warrant a coherent treatment of the main body of differential topology in the realm of Banach manifolds, which is at the same time correct and complete. This book fills the gap: whenever possible the manifolds treated are Banach manifolds with corners. Corners add to the complications and the authors have carefully fathomed the validity of all main results at corners. Even in finite dimensions some results at corners are more complete and better thought out here than elsewhere in the literature. The proofs are correct and with all details. I see this book as a reliable monograph of a well-defined subject; the possibility to fall back to it adds to the feeling of security when climbing in the more dangerous realms of infinite dimensional differential geometry. Peter W. Michor

  7. Ultrasound-Guided Fasciotomy for Anterior Chronic Exertional Compartment Syndrome of the Leg.

    Science.gov (United States)

    Balius, Ramon; Bong, David A; Ardèvol, Jordi; Pedret, Carles; Codina, David; Dalmau, Antonio

    2016-04-01

    Chronic exertional compartment syndrome is characterized by exertional pain and elevated intracompartmental pressures affecting the leg in physically active young people. In patients who have failed conservative measures, fasciotomy is the treatment of choice. This study presents a new method for performing fasciotomy using high-resolution ultrasound (US) guidance and reports on the clinical outcomes in a group of these patients. Over a 3-year period, 7 consecutive patients with a total of 9 involved legs presented clinically with anterior compartment chronic exertional compartment syndrome, which was confirmed by intracompartmental pressure measurements before and after exercise. After a US examination, fasciotomy under US guidance was performed. Preoperative and postoperative pain and activity levels were assessed as well as number of days needed to "return to play." All patients had a decrease in pain, and all except 1 returned to presymptomatic exercise levels with a median return to play of 35 days. © 2016 by the American Institute of Ultrasound in Medicine.

  8. Applied physiology of cycling.

    Science.gov (United States)

    Faria, I E

    1984-01-01

    Historically, the bicycle has evolved through the stages of a machine for efficient human transportation, a toy for children, a finely-tuned racing machine, and a tool for physical fitness development, maintenance and testing. Recently, major strides have been made in the aerodynamic design of the bicycle. These innovations have resulted in new land speed records for human powered machines. Performance in cycling is affected by a variety of factors, including aerobic and anaerobic capacity, muscular strength and endurance, and body composition. Bicycle races range from a 200m sprint to approximately 5000km. This vast range of competitive racing requires special attention to the principle of specificity of training. The physiological demands of cycling have been examined through the use of bicycle ergometers, rollers, cycling trainers, treadmill cycling, high speed photography, computer graphics, strain gauges, electromyography, wind tunnels, muscle biopsy, and body composition analysis. These techniques have been useful in providing definitive data for the development of a work/performance profile of the cyclist. Research evidence strongly suggests that when measuring the cyclist's aerobic or anaerobic capacity, a cycling protocol employing a high pedalling rpm should be used. The research bicycle should be modified to resemble a racing bicycle and the cyclist should wear cycling shoes. Prolonged cycling requires special nutritional considerations. Ingestion of carbohydrates, in solid form and carefully timed, influences performance. Caffeine appears to enhance lipid metabolism. Injuries, particularly knee problems which are prevalent among cyclists, may be avoided through the use of proper gearing and orthotics. Air pollution has been shown to impair physical performance. When pollution levels are high, training should be altered or curtailed. Effective training programmes simulate competitive conditions. Short and long interval training, blended with long

  9. Effects of fitness and self-confidence on time perception during exertion

    Directory of Open Access Journals (Sweden)

    2015-09-01

    Full Text Available Aims: Human physical and psychological features influence perceptions of the environment during activity. If during exercise an individual over-estimates time, they may interpret this as spending longer than necessary under a potentially aversive state of exertion. This may in turn decrease one’s sense of exercise success and tendency to persevere with exercise. We tested if experimentally manipulating sense of exercise self-efficacy would affect time perception during standardised physical exertion. Method: Exercise Self-Efficacy (ESE of 18 -73 year olds (N=51 was measured before and after an exercise challenge of moderate intensity. Height, weight and body fat composition were measured before participants were randomly allocated to one of three groups. After a 4-minute treadmill fitness test, participants were presented with either bogus feedback about their performance (positive or negative or no feedback (control. Before and during exercise, participants estimated a prescribed 2-minute time interval. Ratings of perceived exertion were also measured periodically. Results: Feedback on performance had no significant effect on time perception, even when controlling for individual exertion level. Reported ESE was also unaffected by whether someone received positive, negative or no feedback. Age was again found to be significantly correlated with VO2max, r(51 = .62, p < .001, but in contrast to prior findings, estimates of general fitness such as VO2max, BMI and waist circumference were unrelated to changes in time perception due to exertion. Conclusions: These findings failed to support prior findings and anecdotal evidence suggesting that exertion might alter one’s perception of time. We also failed to find any support for effects on ESE when participants were given explicit performance feedback. Finally, participants’ physical characteristics appear to be unrelated to time perception whilst exercising at moderate intensity.

  10. Cell proliferating and differentiating role of H2O2 in Sclerotium rolfsii and Sclerotinia sclerotiorum.

    Science.gov (United States)

    Papapostolou, Ioannis; Sideri, Marina; Georgiou, Christos D

    2014-01-01

    This study shows that the oxidant and also signal transducing H2O2 exerts a cell proliferating action at certain intracellular concentrations (around 80 nM), by inhibiting the lateral-chained and terminal sclerotial differentiation of the phytopathogenic filamentous fungi S. rolfsii and S. sclerotiorum, respectively. H2O2 also promotes sclerotial differentiation in these fungi at higher intracellular concentrations (approx. 130 nM). A cell proliferating and differentiation inhibiting effect was exerted also by the inhibitor of catalase activity aminotriazole via increase of intracellular H2O2. Copyright © 2013 Elsevier GmbH. All rights reserved.

  11. Playing vs. Nonplaying Aerobic Training in Tennis: Physiological and Performance Outcomes

    OpenAIRE

    Pialoux, Vincent; Genevois, Cyril; Capoen, Arnaud; Forbes, Scott C.; Thomas, Jordan; Rogowski, Isabelle

    2015-01-01

    This study compared the effects of playing and nonplaying high intensity intermittent training (HIIT) on physiological demands and tennis stroke performance in young tennis players. Eleven competitive male players (13.4 ± 1.3 years) completed both a playing and nonplaying HIIT session of equal distance, in random order. During each HIIT session, heart rate (HR), blood lactate, and ratings of perceived exertion (RPE) were monitored. Before and after each HIIT session, the velocity and accuracy...

  12. Physiological responses to four hours of low-level repetitive work

    DEFF Research Database (Denmark)

    Garde, A Helene; Hansen, Åse Marie; Jensen, Bente R

    2003-01-01

    OBJECTIVES: The study investigated physiological responses to 4 hours of standardized low-level repetitive work. It was hypothesized that accumulative effects not observed after 1 hour could be found after 4 hours of repetitive work. METHODS: Ten healthy women performed intermittent (5 seconds + 5...... the 4 hours. In accordance, the RPE recorded for the hand, forearm, and shoulder regions increased progressively. For the remaining physiological measures, no accumulative changes were found. Forearm muscle activity was higher during a mental reference task with lower exerted force than during...

  13. Assessment of Subjective Perceived Exertion at the Anaerobic Threshold with the Borg CR-10 Scale

    OpenAIRE

    Zamunér, Antonio R.; Moreno, Marlene A.; Camargo, Taís M.; Graetz, Juliana P.; Rebelo, Ana C. S.; Tamburús, Nayara Y.; Ester da Silva

    2011-01-01

    The purpose of this study was to evaluate the anaerobic threshold (AT) with a graphic visual method for estimating the intensity of ventilatory and metabolic exertion and to determine the ratings of perceived exertion (RPE) on the Borg CR-10 scale during a continuous ramp type exercise test (CT-R). Forty healthy, physically active and sedentary young women (age 23.1 ± 3.52 years) were divided into two groups according to their fitness level: active group (AG) and sedentary group (SG) and were...

  14. Exertional Heat Stroke and American Football: What the Team Physician Needs to Know.

    Science.gov (United States)

    Sylvester, Jillian E; Belval, Luke N; Casa, Douglas J; O'Connor, Francis G

    Football is recognized as a leading contributor to sports injury secondary to the contact collision nature of the endeavor. While direct deaths from head and spine injury remain a significant contributor to the number of catastrophic injuries, indirect deaths (systemic failure) predominate. Exertional heat stroke has emerged as one of the leading indirect causes of death in high school and collegiate football. This review details for the team physician the unique challenge of exercising in the heat to the football player, and the prevention, diagnosis, management, and return-to-play issues pertinent to exertional heat illnesses.

  15. Diagnosing exertional rhabdomyolysis: a brief review and report of two cases.

    Science.gov (United States)

    Walsworth, M; Kessler, T

    2001-03-01

    Exertional rhabdomyolysis is a potentially dangerous condition that involves release of intracellular contents from skeletal muscle in concentrations that may cause renal or other systemic complications. The purpose of the two case reports presented is to assist clinicians in recognizing this condition and in considering its predisposing factors. This paper describes two patients who, in the presence of several predisposing risk factors, developed exertional rhabdomyolysis. After diagnoses of rhabdomyolysis were reached, both patients were admitted to a local hospital for several days of monitoring and treatment. After 1 to 2 months of activity modification, both patients successfully resumed full physical activity and military duty.

  16. Sickle Cell Trait-Related Exertional Deaths: Observations at Autopsy and Review of the Literature.

    Science.gov (United States)

    Hughes, Rhome L; Feig, James

    2015-08-01

    Sickle cell trait-related exertional deaths, although rare, are well-accepted in the field of forensic pathology; however, the increased risk of sudden unexpected deaths in persons with sickle cell trait undergoing strenuous physical activity may be an underappreciated acute phenomenon in the clinical realm. Herein, we report two cases of sickle cell trait-related exertional deaths of active duty military members, with a review of the literature including the pathophysiology of sickle cell trait-related deaths and current military screening guidelines. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

  17. Vascular hyperpolarization in human physiology and cardiovascular risk conditions and disease.

    Science.gov (United States)

    Schinzari, F; Tesauro, M; Cardillo, C

    2017-01-01

    Hyperpolarization causing smooth muscle relaxation contributes to the maintenance of vascular homeostasis, particularly in small-calibre arteries and arterioles. It may also become a compensatory vasodilator mechanism upregulated in states with impaired nitric oxide (NO) availability. Bioassay of vascular hyperpolarization in the human circulation has been hampered by the complexity of mechanisms involved and the limited availability of investigational tools. Firm evidence, however, supports the notion that hyperpolarization participates in the regulation of resting vasodilator tone and vascular reactivity in healthy subjects. In addition, an enhanced endothelium-derived hyperpolarization contributes to both resting and agonist-stimulated vasodilation in a variety of cardiovascular risk conditions and disease. Thus, hyperpolarization mediated by epoxyeicosatrienoic acids (EETs) and H 2 O 2 has been observed in coronary arterioles of patients with coronary artery disease. Similarly, ouabain-sensitive and EETs-mediated hyperpolarization has been observed to compensate for NO deficiency in patients with essential hypertension. Moreover, in non-hypertensive patients with multiple cardiovascular risk factors and in hypercholesterolaemia, K Ca channel-mediated vasodilation appears to be activated. A novel paradigm establishes that perivascular adipose tissue (PVAT) is an additional regulator of vascular tone/function and endothelium is not the only agent in vascular hyperpolarization. Indeed, some PVAT-derived relaxing substances, such as adiponectin and angiotensin 1-7, may exert anticontractile and vasodilator actions by the opening of K Ca channels in smooth muscle cells. Conversely, PVAT-derived factors impair coronary vasodilation via differential inhibition of some K + channels. In view of adipose tissue abnormalities occurring in human obesity, changes in PVAT-dependent hyperpolarization may be relevant for vascular dysfunction also in this condition. © 2015

  18. Cassava biology and physiology.

    Science.gov (United States)

    El-Sharkawy, Mabrouk A

    2004-11-01

    Cassava or manioc (Manihot esculenta Crantz), a perennial shrub of the New World, currently is the sixth world food crop for more than 500 million people in tropical and sub-tropical Africa, Asia and Latin America. It is cultivated mainly by resource-limited small farmers for its starchy roots, which are used as human food either fresh when low in cyanogens or in many processed forms and products, mostly starch, flour, and for animal feed. Because of its inherent tolerance to stressful environments, where other food crops would fail, it is often considered a food-security source against famine, requiring minimal care. Under optimal environmental conditions, it compares favorably in production of energy with most other major staple food crops due to its high yield potential. Recent research at the Centro Internacional de Agricultura Tropical (CIAT) in Colombia has demonstrated the ability of cassava to assimilate carbon at very high rates under high levels of humidity, temperature and solar radiation,which correlates with productivity across all environments whether dry or humid. When grown on very poor soils under prolonged drought for more than 6 months, the crop reduce both its leaf canopy and transpiration water loss, but its attached leaves remain photosynthetically active, though at greatly reduced rates. The main physiological mechanism underlying such a remarkable tolerance to drought was rapid stomatal closure under both atmospheric and edaphic water stress, protecting the leaf against dehydration while the plant depletes available soil water slowly during long dry periods. This drought tolerance mechanism leads to high crop water use efficiency values. Although the cassava fine root system is sparse, compared to other crops, it can penetrate below 2 m soil,thus enabling the crop to exploit deep water if available. Leaves of cassava and wild Manihot possess elevated activities of the C4 enzyme PEP carboxylase but lack the leaf Kranz anatomy typical of C4

  19. Physiology of Alpine skiing.

    Science.gov (United States)

    Andersen, R E; Montgomery, D L

    1988-10-01

    Physiological profiles of elite Alpine skiers reveal the importance of muscular strength, anaerobic power, anaerobic endurance, aerobic endurance, coordination, agility, balance, and flexibility. On-hill snow training and dryland training programmes should focus on the elevation of these fitness components. Physical characteristics of elite skiers reveal an average height and body mass. Today, successful skiers are taller and heavier than their predecessors. Slalom skiers tend to be leaner than skiers in other events while the downhill racers are the heaviest. Elite skiers have strong legs when peak torque is measured during isometric and isokinetic conditions involving knee extension, which may be a specific adaptation since the skier is in a crouched position for a prolonged period when racing. Leg strength correlates significantly with performance in the downhill and giant slalom events. The glycolytic contribution in the slalom and giant slalom events is about 40% of the total energy cost. Following a race, blood lactate concentration averages 9 to 13 mmol/L. A muscle lactate concentration of 24 mmol/kg wet muscle tissue has been reported. Elite skiers have higher lactate values than advanced or novice skiers. The aerobic demands of competitive Alpine skiing may approach (90 to 95%) of the athlete's maximal aerobic power. Maximal heart rate is achieved during the latter part of the race. Elite skiers have a high VO2max. This may reflect their training programme and not the actual demands of the sport. When turning, muscular activity acts to impede blood flow and oxygen delivery. As a consequence, anaerobic metabolism is increased. Glycogen studies show significant utilisation from both slow and fast twitch muscle fibres. Skilled and unskilled skiers differ with respect to glycogen utilisation. Skilled skiers have greater glycogen depletion in the slow twitch fibres compared to unskilled skiers. Muscle glycogen decreases by about 32 mmol/kg wet muscle tissue

  20. [Physiology of labour: modern theoretical and scientific-practical aspects].

    Science.gov (United States)

    Bukhtiiarov, I V; Matiukhin, V V

    2014-10-01

    Physiology of labour is the science that studies human being in the professional activity process. Theoretical and practical aspects include two fundamental and interrelated trends based on the theory of functional system. The first area concerns the development of criteria-based foundations of differential diagnostics of organism' various functional states, the return of functions and reserve opportunities. The second area is devoted physiological-ergonomic and hygienic standardization of labor process factors, different intensity and duration muscular and mental loads permissible levels substantiation, as well as in view of gender, age and other personal qualities of the employee.

  1. Physiologic changes of pregnancy: A review of the literature.

    Science.gov (United States)

    Motosko, Catherine C; Bieber, Amy Kalowitz; Pomeranz, Miriam Keltz; Stein, Jennifer A; Martires, Kathryn J

    2017-12-01

    Throughout pregnancy, the body undergoes a variety of physiologic changes. The cutaneous findings can be most noticeable and often worrisome to both physicians and patients. Obstetricians and dermatologists must be able to differentiate between changes that are benign and those that may be pathologic. Most physicians recognize benign changes that are commonly described in literature such as hyperpigmentation, melasma, striae gravidarum, and telogen effluvium; however, they may be unaware of changes that tend to be less frequently discussed. This comprehensive review provides a broad overview of the physiologic cutaneous changes that occur during pregnancy as described in the literature over the past 10 years.

  2. Physiologic changes of pregnancy: A review of the literature

    Directory of Open Access Journals (Sweden)

    Catherine C. Motosko, BS

    2017-12-01

    Full Text Available Throughout pregnancy, the body undergoes a variety of physiologic changes. The cutaneous findings can be most noticeable and often worrisome to both physicians and patients. Obstetricians and dermatologists must be able to differentiate between changes that are benign and those that may be pathologic. Most physicians recognize benign changes that are commonly described in literature such as hyperpigmentation, melasma, striae gravidarum, and telogen effluvium; however, they may be unaware of changes that tend to be less frequently discussed. This comprehensive review provides a broad overview of the physiologic cutaneous changes that occur during pregnancy as described in the literature over the past 10 years. Keywords: pregnancy, hyperpigmentation, acne, melasma

  3. A comparison of a maximum exertion method and a model-based, sub-maximum exertion method for normalizing trunk EMG.

    Science.gov (United States)

    Cholewicki, Jacek; van Dieën, Jaap; Lee, Angela S; Reeves, N Peter

    2011-10-01

    The problem with normalizing EMG data from patients with painful symptoms (e.g., low back pain) is that such patients may be unwilling or unable to perform maximum exertions. Furthermore, the normalization to a reference signal, obtained from a maximal or sub-maximal task, tends to mask differences that might exist as a result of pathology. Therefore, we presented a novel method (GAIN method) for normalizing trunk EMG data that overcomes both problems. The GAIN method does not require maximal exertions (MVC) and tends to preserve distinct features in the muscle recruitment patterns for various tasks. Ten healthy subjects performed various isometric trunk exertions, while EMG data from 10 muscles were recorded and later normalized using the GAIN and MVC methods. The MVC method resulted in smaller variation between subjects when tasks were executed at the three relative force levels (10%, 20%, and 30% MVC), while the GAIN method resulted in smaller variation between subjects when the tasks were executed at the three absolute force levels (50 N, 100 N, and 145 N). This outcome implies that the MVC method provides a relative measure of muscle effort, while the GAIN-normalized data gives an estimate of the absolute muscle force. Therefore, the GAIN-normalized data tends to preserve the differences between subjects in the way they recruit their muscles to execute various tasks, while the MVC-normalized data will tend to suppress such differences. The appropriate choice of the EMG normalization method will depend on the specific question that an experimenter is attempting to answer. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. LYSOSOMAL PHYSIOLOGY IN TETRAHYMENA

    Science.gov (United States)

    Rothstein, Thomas L.; Blum, J. J.

    1974-01-01

    The ingestion of 14C-labeled 9,10-dimethyl-1,2-benzanthracene particles, the extracellular release of acid phosphatase, ribonuclease, and α-glucosidase, and the egestion of preingested dimethylbenzanthracene particles by Tetrahymena taken from logarithmically growing cultures and resuspended in a dilute salt solution were followed in the presence of several pharmacologic agents. Serotonin, caffeine, and, to a lesser extent, dibutyryl cyclic AMP increased the rate of particle ingestion, but did not alter the rate of release of the three acid hydrolases studied. Added catecholamines did not affect either particle ingestion or acid hydrolase release, but particle ingestion was inhibited by the catecholamine antagonists, dichloroisoproterenol, desmethylimipramine, reserpine, and phenoxybenzamine. These drugs also increased the release of acid phosphatase and ribonuclease in 5-h incubations. Desmethylimipramine acted within 1 h to increase acid hydrolase release, but the effect of dichloroisoproterenol developed more slowly and was secondary to a change in cellular content of the hydrolases. Desmethylimipramine increased the energy of activation for the release of acid phosphatase, while dichloroisoproterenol did not. Both of these drugs enhanced the egestion of preingested dimethylbenzanthracene particles, supporting the view that acid hydrolase release occurs through a cytoproct egestion mechanism. Particle ingestion was also inhibited by colchicine, vinblastine, and cytochalasin B, but these agents had no effect on acid hydrolase release, thus further differentiating the properties of the ingestion mechanism from those of the egestion mechanism. It appears that both microtubules and microfilaments play a role in the ingestion process and that this process may be controlled in part by a cyclic AMP-mediated serotoninergic and adrenergic system. PMID:4152946

  5. Genetic background specific hypoxia resistance in rat is correlated with balanced activation of a cross-chromosomal genetic network centering on physiological homeostasis

    Directory of Open Access Journals (Sweden)

    Lei eMao

    2012-10-01

    Full Text Available Genetic background of an individual can drastically influence an organism’s response upon environmental stress and pathological stimulus. Previous studies in inbred rats showed that compared to Brown Norway (BN, Dahl salt-sensitive (SS rat exerts strong hypoxia susceptibility. However, despite extensive narrow-down approaches via the chromosome substitution methodology, this genome-based physiological predisposition could not be traced back to distinct quantitative trait loci. Upon the completion and public data availability of PhysGen SS-BN consomic rat platform, I employed systems biology approach attempting to further our understanding of the molecular basis of genetic background effect in light of hypoxia response. I analyzed the physiological screening data of 22 consomic rat strains under normoxia and two-weeks of hypoxia, and cross-compared them to the parental strains. The analyses showed that SS-9BN and SS-18BN represent the most hypoxia resistant CS strains with phenotype similar to BN, whereas SS-6BN and SS-YBN segregated to the direction of SS. A meta-analysis on the transcriptomic profiles of these consomic rat strains under hypoxia treatment showed that although polymorphisms on the substituted BN chromosomes could be directly involved in hypoxia resistance, this seems to be embedded in a more complex trans-chromosomal genetic regulatory network. Via information theory based modeling approach, this hypoxia-relevant core genetic network was reverse-engineered. Network analyses showed that the protective effects of BN chromosome 9 and 18 were reflected by a balanced activation of this core network centering on physiological homeostasis. Presumably, it is the system robustness constituted on such differential network activation that acts as hypoxia response modifier. Understanding of the intrinsic link between the individual genetic background and the network robustness will set a basis in the current scientific efforts toward

  6. Differential topology

    CERN Document Server

    Guillemin, Victor

    2010-01-01

    Differential Topology provides an elementary and intuitive introduction to the study of smooth manifolds. In the years since its first publication, Guillemin and Pollack's book has become a standard text on the subject. It is a jewel of mathematical exposition, judiciously picking exactly the right mixture of detail and generality to display the richness within. The text is mostly self-contained, requiring only undergraduate analysis and linear algebra. By relying on a unifying idea-transversality-the authors are able to avoid the use of big machinery or ad hoc techniques to establish the main

  7. Differential geometry

    CERN Document Server

    Ciarlet, Philippe G

    2007-01-01

    This book gives the basic notions of differential geometry, such as the metric tensor, the Riemann curvature tensor, the fundamental forms of a surface, covariant derivatives, and the fundamental theorem of surface theory in a selfcontained and accessible manner. Although the field is often considered a classical one, it has recently been rejuvenated, thanks to the manifold applications where it plays an essential role. The book presents some important applications to shells, such as the theory of linearly and nonlinearly elastic shells, the implementation of numerical methods for shells, and

  8. Differential equations

    CERN Document Server

    Tricomi, FG

    2013-01-01

    Based on his extensive experience as an educator, F. G. Tricomi wrote this practical and concise teaching text to offer a clear idea of the problems and methods of the theory of differential equations. The treatment is geared toward advanced undergraduates and graduate students and addresses only questions that can be resolved with rigor and simplicity.Starting with a consideration of the existence and uniqueness theorem, the text advances to the behavior of the characteristics of a first-order equation, boundary problems for second-order linear equations, asymptotic methods, and diff

  9. Unravelling the grey zone : Cardiac MRI volume to wall mass ratio to differentiate hypertrophic cardiomyopathy and the athlete's heart

    NARCIS (Netherlands)

    Luijkx, Tim; Cramer, Maarten J.; Buckens, Stan; Zaidi, Abbas; Rienks, R; Mosterd, Arend; Prakken, Niek H J; Dijkman, Barbara; Mali, W.P.; Velthuis, BK

    2015-01-01

    Background Differentiating physiological left ventricular hypertrophy (LVH) in athletes from pathological hypertrophic cardiomyopathy (HCM) can be challenging. This study assesses the ability of cardiac MRI (CMR) to distinguish between physiological LVH (so-called athlete's heart) and HCM. Methods

  10. Investigation of Forces Exerted During the Expansion of Nanomechanically Tensioned Organosilica Materials

    Science.gov (United States)

    Albon, Theresa; Edmiston, Paul; Lehman, Susan

    2012-02-01

    Osorbis a sol-gel derived organosilica that instantaneously swells up to four times in volume with organic liquids. The nanoporous glass-like material is hydrophobic and does not swell in water but absorbs non-polar organic solutes from aqueous solution. Swelling due to absorption of organic solutes, liquids, or gases leads to the generation of substantial mechanical force, presumably derived from the relaxation of the interconnected network of organosilica nanoparticles that comprise the material. We have investigated the force exerted by placing a powdered sample in a cylinder with a freely movable piston. As solvent percolates into the cylinder from below, the exerted force is measured by a load cell. The piston is then gradually moved upward to allow the material to expand. As the sample just begins to swell, we have routinely observed forces in excess of 500 N per gram; the exerted force then decreases as the volume is allowed to increase. The relationship between the exerted force and sample volume is shown to be exponential, and we define the exponential decay constant as the characteristic volume Vc. We also determine the absorption capacity and fractional change in volume of the organosilica samples, and correlate these with changes in Vc.

  11. Fluoxetine exerts age-dependent effects on behavior and amygdala neuroplasticity in the rat.

    NARCIS (Netherlands)

    Homberg, J.R.; Olivier, J.D.A.; Blom, T.; Arentsen, T.; Brunschot, C. van; Schipper, P.; Korte-Bouws, G.A.; Luijtelaar, E.L.J.M. van; Reneman, L.

    2011-01-01

    The selective serotonin reuptake inhibitor (SSRI) Prozac(R) (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and

  12. Fluoxetine Exerts Age-Dependent Effects on Behavior and Amygdala Neuroplasticity in the Rat

    NARCIS (Netherlands)

    Homberg, J.R.; Olivier, J.D.A.; Blom, T.; Arentsen, T.; Brunschot, C. van; Schipper, P.; Korte-Bouws, G.A.; Luijtelaar, E.L.J.M. van; Reneman, L.

    2011-01-01

    The selective serotonin reuptake inhibitor (SSRI) Prozac® (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and thereby

  13. Fluoxetine exerts age-dependent effects on behavior and amygdala neuroplasticity in the rat

    NARCIS (Netherlands)

    Homberg, J.R.; Olivier, J.D.A.; Blom, T.; Arentsen, T.; Brunschot, C. van; Schipper, P.; Korte-Bouws, G.A.; Luijtelaar, E.L.J.M. van; Reneman, L.

    2011-01-01

    The selective serotonin reuptake inhibitor (SSRI) Prozac(R) (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and

  14. Respiratory and immune response to maximal physical exertion following exposure to secondhand smoke in healthy adults.

    Directory of Open Access Journals (Sweden)

    Andreas D Flouris

    Full Text Available We assessed the cardiorespiratory and immune response to physical exertion following secondhand smoke (SHS exposure through a randomized crossover experiment. Data were obtained from 16 (8 women non-smoking adults during and following a maximal oxygen uptake cycling protocol administered at baseline and at 0-, 1-, and 3- hours following 1-hour of SHS set at bar/restaurant carbon monoxide levels. We found that SHS was associated with a 12% decrease in maximum power output, an 8.2% reduction in maximal oxygen consumption, a 6% increase in perceived exertion, and a 6.7% decrease in time to exhaustion (P<0.05. Moreover, at 0-hours almost all respiratory and immune variables measured were adversely affected (P<0.05. For instance, FEV(1 values at 0-hours dropped by 17.4%, while TNF-α increased by 90.1% (P<0.05. At 3-hours mean values of cotinine, perceived exertion and recovery systolic blood pressure in both sexes, IL4, TNF-α and IFN-γ in men, as well as FEV(1/FVC, percent predicted FEV(1, respiratory rate, and tidal volume in women remained different compared to baseline (P<0.05. It is concluded that a 1-hour of SHS at bar/restaurant levels adversely affects the cardiorespiratory and immune response to maximal physical exertion in healthy nonsmokers for at least three hours following SHS.

  15. Fluoxetine Exerts Age-Dependent Effects on Behavior and Amygdala Neuroplasticity in the Rat

    NARCIS (Netherlands)

    Homberg, J.R.; Olivier, J.D.A.; Blom, T.; Arentsen, T.; van Brunschot, C.; Schipper, P.; Korte-Bouws, G.; van Luijtelaar, G.; Reneman, L.

    2011-01-01

    The selective serotonin reuptake inhibitor (SSRI) Prozac (R) (fluoxetine) is the only registered antidepressant to treat depression in children and adolescents. Yet, while the safety of SSRIs has been well established in adults, serotonin exerts neurotrophic actions in the developing brain and

  16. Post-exertion neurocognitive test failure among student-athletes following concussion.

    Science.gov (United States)

    McGrath, Neal; Dinn, Wayne M; Collins, Michael W; Lovell, Mark R; Elbin, R J; Kontos, Anthony P

    2013-01-01

    The purpose of the present study was to examine post-exertion (PE) neurocognitive performance among student-athletes following concussion who were asymptomatic and returned to baseline normal neurocognitive test levels at rest. This study examined the neurocognitive performance of a sub-set of student-athletes who 'failed' to perform at baseline levels of neurocognitive function, i.e. exhibited downward reliable change index (RCI) alterations following a moderate exertional protocol during recovery from concussion. A retrospective records review was carried out of Immediate Post-concussion Assessment and Cognitive Testing (ImPACT) and neuropsychological consultation data among athletes with sports-related concussion from a network of 22 schools and one junior hockey programme. Fifty-four student-athletes met inclusion criteria and participated in the study. A total of 27.7% of concussed student-athletes who were symptom-free and returned to baseline on ImPACT at rest (i.e. no longer demonstrated performance deficits on neurocognitive tests) exhibited cognitive decline following moderate physical exertion. The PE cognitive changes were not simply general performance effects, but significant changes in memory ability in the presence of intact processing speed functions. The PE-Pass and PE-Fail groups did not, however, differ on post-concussive symptoms or concussion history. Clinicians' return-to-play evaluation protocols should include post-exertional computerized neurocognitive testing.

  17. Influence of ambient music on perceived exertion during a pulmonary rehabilitation session: a randomized crossover study.

    Science.gov (United States)

    Reychler, Gregory; Mottart, Florian; Boland, Maelle; Wasterlain, Emmanuelle; Pieters, Thierry; Caty, Gilles; Liistro, Giuseppe

    2015-05-01

    Pulmonary rehabilitation is a key element in the treatment of COPD. Music has been shown to have a positive effect on parameters related to a decrease in exercise tolerance. The aim of this study was to evaluate the effect of listening to ambient music on perceived exertion during a pulmonary rehabilitation session for COPD subjects. COPD subjects randomly performed a session of pulmonary rehabilitation with or without ambient music. Perceived exertion (Borg scales), anxiety (Hospital Anxiety and Depression Scale-Anxiety Subscale), dyspnea (visual analog scale), and cardiorespiratory parameters were compared at the end of both sessions. Forty-one subjects were analyzed. The characteristics of the COPD subjects were as follows: age, 70.5 ± 8.4 y; body mass index, 22.7 ± 3.9 kg/m(2); and FEV1, 38.6 ± 12.5 % predicted. Perceived exertion was not modified by ambient music, but anxiety was improved (P = .02). Dyspnea, fatigue and cardiorespiratory parameters were not influenced by music during a typical session of the pulmonary rehabilitation program. This study demonstrates that perceived exertion during one pulmonary rehabilitation session was not influenced by ambient music. However, a positive effect on anxiety was observed. (ClinicalTrials.gov registration NCT01833260.). Copyright © 2015 by Daedalus Enterprises.

  18. Hydrocortisone Infusion Exerts Dose- and Sex-Dependent Effects on Attention to Emotional Stimuli

    Science.gov (United States)

    Breitberg, Alaina; Drevets, Wayne C.; Wood, Suzanne E.; Mah, Linda; Schulkin, Jay; Sahakian, Barbara J.; Erickson, Kristine

    2013-01-01

    Glucocorticoid administration has been shown to exert complex effects on cognitive and emotional processing. In the current study we investigated the effects of glucocorticoid administration on attention towards emotional words, using an Affective Go/No-go task on which healthy humans have shown an attentional bias towards positive as compared to…

  19. Oxytocin microinjected into the central amygdaloid nuclei exerts anti-aggressive effects in male rats

    NARCIS (Netherlands)

    Calcagnoli, Federica; Stubbendorff, Christine; Meyer, Neele; de Boer, Sietse F.; Althaus, Monika; Koolhaas, Jacob

    We recently demonstrated that acute and chronic intracerebroventricular enhancement of brain OXT levels induces potent anti-aggressive and pro-social explorative effects during social challenges. However, the exact anatomical location in the brain where OXT exerts its action is still elusive. In the

  20. Energetics, physiology and vertebrate ecology.

    Science.gov (United States)

    Karasov, W H

    1986-10-01

    The magnitude of energy flow through individual animals and their populations is potentially limited by several physiological factors. These include thermal constraints affecting the time available for foraging, physiological design constraints affecting foraging mode and the rate of prey capture, and digestive constraints on how much food can be processed per day. Over short periods (hours or less), maximal rates of metabolism may determine survival during exposure to cold or when fleeing predators. Energetics, physiology and ecology can be usefully integrated within the context of the concept of maximum rate of energy flow. Copyright © 1986. Published by Elsevier Ltd.

  1. Differential accumulation of flavonoids by tomato (Solanum ...

    African Journals Online (AJOL)

    SARAH

    2014-12-29

    Dec 29, 2014 ... ABSTRACT. Objective: Little is known about physiological functions of flavonoids, specifically in the course of maturation and ripening of fruits. Spatiotemporal changes in the levels of flavonoids were investigated in the present study with focus on possible functional differentiation of individual compounds ...

  2. Stochastic Differential Equations in Artificial Pancreas Modelling

    DEFF Research Database (Denmark)

    Duun-Henriksen, Anne Katrine

    . However, uncertainty in the model occurs due to the nature of physiological systems and due to the presence of unknown disturbances. An attractive approach to deal with this uncertainty is to use stochastic differential equations (SDEs). In a model based on SDEs, the noise is separated into two terms: 1...

  3. Punicalagin promotes human villous trophoblast differentiation.

    Science.gov (United States)

    Chen, Baosheng; Longtine, Mark S; Costa, Maria Laura; Nelson, D Michael

    2016-08-01

    Poor differentiation of trophoblasts is associated with placental dysfunction, predisposing women to multiple pregnancy disorders. Punicalagin, a prominent ellagitannin in pomegranate juice has been shown to exert anti-apoptosis and anti-oxidative effects in human trophoblasts. We hypothesized that punicalagin modulates trophoblast differentiation. We found that punicalagin-treated primary trophoblast showed reduced E-cadherin, higher Syncytin 1, more β-hCG, and increased GCM1, an upstream regulator of β-hCG. Punicalagin exposure of villous explants enhanced the number of cytotrophoblasts expressing the proliferation marker Ki67. We conclude that punicalagin enhances trophoblast differentiation and speculate that punicalagin might be used therapeutically in pregnancies at risk for placental dysfunction. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Physiological adaptations to weight loss and factors favouring weight regain.

    Science.gov (United States)

    Greenway, F L

    2015-08-01

    Obesity is a major global health problem and predisposes individuals to several comorbidities that can affect life expectancy. Interventions based on lifestyle modification (for example, improved diet and exercise) are integral components in the management of obesity. However, although weight loss can be achieved through dietary restriction and/or increased physical activity, over the long term many individuals regain weight. The aim of this article is to review the research into the processes and mechanisms that underpin weight regain after weight loss and comment on future strategies to address them. Maintenance of body weight is regulated by the interaction of a number of processes, encompassing homoeostatic, environmental and behavioural factors. In homoeostatic regulation, the hypothalamus has a central role in integrating signals regarding food intake, energy balance and body weight, while an 'obesogenic' environment and behavioural patterns exert effects on the amount and type of food intake and physical activity. The roles of other environmental factors are also now being considered, including sleep debt and iatrogenic effects of medications, many of which warrant further investigation. Unfortunately, physiological adaptations to weight loss favour weight regain. These changes include perturbations in the levels of circulating appetite-related hormones and energy homoeostasis, in addition to alterations in nutrient metabolism and subjective appetite. To maintain weight loss, individuals must adhere to behaviours that counteract physiological adaptations and other factors favouring weight regain. It is difficult to overcome physiology with behaviour. Weight loss medications and surgery change the physiology of body weight regulation and are the best chance for long-term success. An increased understanding of the physiology of weight loss and regain will underpin the development of future strategies to support overweight and obese individuals in their efforts

  5. Physiological adaptations to weight loss and factors favouring weight regain

    Science.gov (United States)

    Greenway, F L

    2015-01-01

    Obesity is a major global health problem and predisposes individuals to several comorbidities that can affect life expectancy. Interventions based on lifestyle modification (for example, improved diet and exercise) are integral components in the management of obesity. However, although weight loss can be achieved through dietary restriction and/or increased physical activity, over the long term many individuals regain weight. The aim of this article is to review the research into the processes and mechanisms that underpin weight regain after weight loss and comment on future strategies to address them. Maintenance of body weight is regulated by the interaction of a number of processes, encompassing homoeostatic, environmental and behavioural factors. In homoeostatic regulation, the hypothalamus has a central role in integrating signals regarding food intake, energy balance and body weight, while an ‘obesogenic' environment and behavioural patterns exert effects on the amount and type of food intake and physical activity. The roles of other environmental factors are also now being considered, including sleep debt and iatrogenic effects of medications, many of which warrant further investigation. Unfortunately, physiological adaptations to weight loss favour weight regain. These changes include perturbations in the levels of circulating appetite-related hormones and energy homoeostasis, in addition to alterations in nutrient metabolism and subjective appetite. To maintain weight loss, individuals must adhere to behaviours that counteract physiological adaptations and other factors favouring weight regain. It is difficult to overcome physiology with behaviour. Weight loss medications and surgery change the physiology of body weight regulation and are the best chance for long-term success. An increased understanding of the physiology of weight loss and regain will underpin the development of future strategies to support overweight and obese individuals in their

  6. Exertional Rhabdomyolysis in a 21-Year-Old Healthy Woman: A Case Report.

    Science.gov (United States)

    McKay, Brianna D; Yeo, Noelle M; Jenkins, Nathaniel D M; Miramonti, Amelia A; Cramer, Joel T

    2017-05-01

    McKay, BD, Yeo, NM, Jenkins, NDM, Miramonti, AA, and Cramer, JT. Exertional rhabdomyolysis in a 21-year-old healthy woman: a case report. J Strength Cond Res 31(5): 1403-1410, 2017-The optimal resistance training program to elicit muscle hypertrophy has been recently debated and researched. Although 3 sets of 10 repetitions at 70-80% of the 1 repetition maximum (1RM) are widely recommended, recent studies have shown that low-load (∼30% 1RM) high-repetition (3 sets of 30-40 repetitions) resistance training can elicit similar muscular hypertrophy. Incidentally, this type of resistance training has gained popularity. In the process of testing this hypothesis in a research study in our laboratory, a subject was diagnosed with exertional rhabdomyolysis after completing a resistance training session that involved 3 sets to failure at 30% 1RM. Reviewed were the events leading up to and throughout the diagnosis of exertional rhabdomyolysis in a healthy recreationally-trained 21-year-old woman who was enrolled in a study that compared the acute effects of high-load low-repetition vs. low-load high-repetition resistance training. The subject completed a total of 143 repetitions of the bilateral dumbbell biceps curl exercise. Three days after exercise, she reported excessive muscle soreness and swelling and sought medical attention. She was briefly hospitalized and then discharged with instructions to take acetaminophen for soreness, drink plenty of water, rest, and monitor her creatine kinase (CK) concentrations. Changes in the subject's CK concentrations, ultrasound-determined muscle thickness, and echo intensity monitored over a 14-day period are reported. This case illustrates the potential risk of developing exertional rhabdomyolysis after a low-load high-repetition resistance training session in healthy, young, recreationally-trained women. The fact that exertional rhabdomyolysis is a possible outcome may warrant caution when prescribing this type of resistance

  7. Self-reported post-exertional fatigue in Gulf War veterans: roles of autonomic testing

    Directory of Open Access Journals (Sweden)

    Mian eLi

    2014-01-01

    Full Text Available To determine if objective evidence of autonomic dysfunction exists from a group of Gulf War veterans with self-reported post-exertional fatigue, we evaluated 16 Gulf War ill veterans and 12 Gulf War controls. Participants of the ill group had self- reported, unexplained chronic post-exertional fatigue and the illness symptoms had persisted for years until the current clinical study. The controls had no self-reported post-exertional fatigue either at the time of initial survey nor at the time of the current study. We intended to identify clinical autonomic disorders using autonomic and neurophysiologic testing in the clinical context. We compared the autonomic measures between the 2 groups on cardiovascular function at both baseline and head-up tilt, and sudomotor function. We identified 1 participant with orthostatic hypotension, 1 posture orthostatic tachycardia syndrome, 2 distal small fiber neuropathy, and 1 length dependent distal neuropathy affecting both large and small fiber in the ill group; whereas none of above definable diagnoses was noted in the controls. The ill group had a significantly higher baseline heart rate compared to controls. Compound autonomic scoring scale showed a significant higher score (95% CI of mean: 1.72 to 2.67 among ill group compared to controls (0.58 to 1.59. We conclude that objective autonomic testing is necessary for the evaluation of self-reported, unexplained post-exertional fatigue among some Gulf War veterans with multi-symptom illnesses. Our observation that ill veterans with self-reported post-exertional fatigue had objective autonomic measures that were worse than controls warrants validation in a larger clinical series.

  8. Stress before Puberty Exerts a Sex- and Age-Related Impact on Auditory and Contextual Fear Conditioning in the Rat

    Directory of Open Access Journals (Sweden)

    Maria Toledo-Rodriguez

    2007-01-01

    Full Text Available Adolescence is a period of major physical, hormonal, and psychological changes. It is also characterized by a significant increase in the incidence of psychopathologies and this increase is gender-specific. Stress during adolescence is associated with the development of psychiatric disorders later in life. In this study, we evaluated the impact of psychogenic stress (exposure to predator odor followed by placement on an elevated platform experienced before puberty (days 28–30 on fear memories and hormonal response of male and female rats during adolescence and early adulthood. Stress before puberty impacted in a sex- and age-specific way on the responses to auditory and contextual fear conditioning in adolescence and adulthood: (a increased conditioned fear to the tone in males during adolescence but not during adulthood; (b impaired extinction to the tone in adult males; and (c reduced freezing responses to the context in adolescent females. Stress before puberty did not influence the corticosterone levels 30 minutes after an additional stressor given in adulthood. These results indicate that stress experienced prior to puberty can exert a sex-related differential impact on fear-related behaviors displayed by individuals during late adolescence and early adulthood.

  9. Transplantation of Human Neural Stem Cells in a Parkinsonian Model Exerts Neuroprotection via Regulation of the Host Microenvironment

    Directory of Open Access Journals (Sweden)

    Fu-Xing Zuo

    2015-11-01

    Full Text Available Parkinson’s disease (PD is characterized by a progressive loss of dopaminergic neurons and consequent dopamine (DA deficit, and current treatment still remains a challenge. Although neural stem cells (NSCs have been evaluated as appealing graft sources, mechanisms underlying the beneficial phenomena are not well understood. Here, we investigate whether human NSCs (hNSCs transplantation could provide neuroprotection against DA depletion by recruiting endogenous cells to establish a favorable niche. Adult mice subjected to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP were transplanted with hNSCs or vehicle into the striatum. Behavioral and histological analyses demonstrated significant neurorescue response observed in hNSCs-treated animals compared with the control mice. In transplanted animals, grafted cells survived, proliferated, and migrated within the astrocytic scaffold. Notably, more local astrocytes underwent de-differentiation, acquiring the properties of NSCs or neural precursor cells (NPCs in mice given hNSCs. Additionally, we also detected significantly higher expression of host-derived growth factors in hNSCs-transplanted mice compared with the control animals, together with inhibition of local microglia and proinflammatory cytokines. Overall, our results indicate that hNSCs transplantation exerts neuroprotection in MPTP-insulted mice via regulating the host niche. Harnessing synergistic interaction between the grafts and host cells may help optimize cell-based therapies for PD.

  10. Regulatory T Cell Induced by Poria cocos Bark Exert Therapeutic Effects in Murine Models of Atopic Dermatitis and Food Allergy.

    Science.gov (United States)

    Bae, Min-Jung; See, Hye-Jeong; Choi, Gyeyoung; Kang, Chang-Yuil; Shon, Dong-Hwa; Shin, Hee Soon

    2016-01-01

    The prevalence of allergic disorders including atopic dermatitis (AD) and food allergy (FA) has increased dramatically in pediatric populations, but there is no effective drug available for their management. Therefore, trials are required for the development of safe therapeutic agents such as herbal medicines. We determined whether orally administered Poria cocos bark (PCB) extract could exert immunosuppressive effects on allergic and inflammatory symptoms of AD and FA. For both AD, which was induced using house dust mite extract, and FA, which was induced by exposure to ovalbumin, model mice were orally treated with PCB extract for 62 days and 18 days, respectively. We also investigated the inductive effect of PCB extract on the generation and maintenance of Foxp3(+)CD4(+) regulatory T cells (Tregs). The symptoms of AD and FA were ameliorated by the administration of PCB extract. Furthermore, PCB extract inhibited the Th2-related cytokines and increased the population of Foxp3(+)CD4(+) Tregs in both AD and FA models. In ex vivo experiments, PCB extract promoted the functional differentiation of Foxp3(+)CD4(+) Tregs, which is dependent on aryl hydrocarbon receptor activation. Thus, PCB extract has potential as an oral immune suppressor for the treatment of AD and FA through the generation of Tregs.

  11. Regulatory T Cell Induced by Poria cocos Bark Exert Therapeutic Effects in Murine Models of Atopic Dermatitis and Food Allergy

    Directory of Open Access Journals (Sweden)

    Min-Jung Bae

    2016-01-01

    Full Text Available The prevalence of allergic disorders including atopic dermatitis (AD and food allergy (FA has increased dramatically in pediatric populations, but there is no effective drug available for their management. Therefore, trials are required for the development of safe therapeutic agents such as herbal medicines. We determined whether orally administered Poria cocos bark (PCB extract could exert immunosuppressive effects on allergic and inflammatory symptoms of AD and FA. For both AD, which was induced using house dust mite extract, and FA, which was induced by exposure to ovalbumin, model mice were orally treated with PCB extract for 62 days and 18 days, respectively. We also investigated the inductive effect of PCB extract on the generation and maintenance of Foxp3+CD4+ regulatory T cells (Tregs. The symptoms of AD and FA were ameliorated by the administration of PCB extract. Furthermore, PCB extract inhibited the Th2-related cytokines and increased the population of Foxp3+CD4+ Tregs in both AD and FA models. In ex vivo experiments, PCB extract promoted the functional differentiation of Foxp3+CD4+ Tregs, which is dependent on aryl hydrocarbon receptor activation. Thus, PCB extract has potential as an oral immune suppressor for the treatment of AD and FA through the generation of Tregs.

  12. Transplantation of Human Neural Stem Cells in a Parkinsonian Model Exerts Neuroprotection via Regulation of the Host Microenvironment.

    Science.gov (United States)

    Zuo, Fu-Xing; Bao, Xin-Jie; Sun, Xi-Cai; Wu, Jun; Bai, Qing-Ran; Chen, Guo; Li, Xue-Yuan; Zhou, Qiang-Yi; Yang, Yuan-Fan; Shen, Qin; Wang, Ren-Zhi

    2015-11-05

    Parkinson's disease (PD) is characterized by a progressive loss of dopaminergic neurons and consequent dopamine (DA) deficit, and current treatment still remains a challenge. Although neural stem cells (NSCs) have been evaluated as appealing graft sources, mechanisms underlying the beneficial phenomena are not well understood. Here, we investigate whether human NSCs (hNSCs) transplantation could provide neuroprotection against DA depletion by recruiting endogenous cells to establish a favorable niche. Adult mice subjected to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were transplanted with hNSCs or vehicle into the striatum. Behavioral and histological analyses demonstrated significant neurorescue response observed in hNSCs-treated animals compared with the control mice. In transplanted animals, grafted cells survived, proliferated, and migrated within the astrocytic scaffold. Notably, more local astrocytes underwent de-differentiation, acquiring the properties of NSCs or neural precursor cells (NPCs) in mice given hNSCs. Additionally, we also detected significantly higher expression of host-derived growth factors in hNSCs-transplanted mice compared with the control animals, together with inhibition of local microglia and proinflammatory cytokines. Overall, our results indicate that hNSCs transplantation exerts neuroprotection in MPTP-insulted mice via regulating the host niche. Harnessing synergistic interaction between the grafts and host cells may help optimize cell-based therapies for PD.

  13. Superparamagnetic iron oxide nanoparticles exert different cytotoxic effects on cells grown in monolayer cell culture versus as multicellular spheroids

    Energy Technology Data Exchange (ETDEWEB)

    Theumer, Anja; Gräfe, Christine; Bähring, Franziska [Department of Hematology and Oncology, Jena University Hospital, Erlanger Allee 101, 07747 Jena (Germany); Bergemann, Christian [Chemicell GmbH, Eresburgstrasse 22–23, 12103 Berlin (Germany); Hochhaus, Andreas [Department of Hematology and Oncology, Jena University Hospital, Erlanger Allee 101, 07747 Jena (Germany); Clement, Joachim H., E-mail: joachim.clement@med.uni-jena.de [Department of Hematology and Oncology, Jena University Hospital, Erlanger Allee 101, 07747 Jena (Germany)

    2015-04-15

    The aim of this study was to investigate the interaction of superparamagnetic iron oxide nanoparticles (SPION) with human blood–brain barrier-forming endothelial cells (HBMEC) in two-dimensional cell monolayers as well as in three-dimensional multicellular spheroids. The precise nanoparticle localisation and the influence of the NP on the cellular viability and the intracellular Akt signalling were studied in detail. Long-term effects of different polymer-coated nanoparticles (neutral fluidMAG-D, anionic fluidMAG-CMX and cationic fluidMAG-PEI) and the corresponding free polymers on cellular viability of HBMEC were investigated by real time cell analysis studies. Nanoparticles exert distinct effects on HBMEC depending on the nanoparticles' surface charge and concentration, duration of incubation and cellular context. The most severe effects were caused by PEI-coated nanoparticles. Concentrations above 25 µg/ml led to increased amounts of dead cells in monolayer culture as well as in multicellular spheroids. On the level of intracellular signalling, context-dependent differences were observed. Monolayer cultures responded on nanoparticle incubation with an increase in Akt phosphorylation whereas spheroids on the whole show a decreased Akt activity. This might be due to the differential penetration and distribution of PEI-coated nanoparticles.

  14. Olfaction: anatomy, physiology and behavior

    OpenAIRE

    Benignus, Vernon A.; Prah, James D.

    1982-01-01

    The anatomy, physiology and function of the olfactory system are reviewed, as are the normal effects of olfactory stimulation. It is speculated that olfaction may have important but unobtrusive effects on human behavior.

  15. Physiological anthropology: past and future.

    Science.gov (United States)

    Steegmann, A Theodore

    2006-01-01

    Environmental studies in adaptive human biology by North American anthropologists have a history of strong investigative research. From both laboratory and field work, we have gained major insights into human response to physical and social challenges. While these results were considered by most professionals to belong within evolutionary biology, in fact the intellectual structure sprang almost entirely from physiological equilibrium models. Consequently, physiological process itself was the focus. Further, most of the physiological patterns were not linked directly to important outcomes such as work output, reproductive success or survival. About 1975, American physiological anthropologists, led by Paul Baker, turned to studies of health, change and stress response. These studies were strong, but were still neither genetic nor evolutionary in intellectual structure. Evolutionary human biology was taken over by a new body of theory now called "behavior ecology", positing that selfish genes control human behavior to promote their own reproduction. This was paralleled by strong use of evolutionary theory in some areas of molecular biology. However, although physiological anthropologists have not focused on evolution, we have been developing powerful causal models that incorporate elements of physiology, morphology, physical environment and cultural behavior. In these "proximate" biocultural models, it is of little importance whether outcomes such as work or energy management are genetically based. Our future offers two major challenges. First, we must confirm causal links between specific physiological patterns and outcomes of practical importance to individuals and societies. Second, if we are to take our place in evolutionary biology, the one overarching theory of life on earth, we must understand the heritability of physiological traits, and determine whether they play a role in survival and reproduction.

  16. Behavioral and physiological consequences of sleep restriction.

    Science.gov (United States)

    Banks, Siobhan; Dinges, David F

    2007-08-15

    Adequate sleep is essential for general healthy functioning. This paper reviews recent research on the effects of chronic sleep restriction on neurobehavioral and physiological functioning and discusses implications for health and lifestyle. Restricting sleep below an individual's optimal time in bed (TIB) can cause a range of neurobehavioral deficits, including lapses of attention, slowed working memory, reduced cognitive throughput, depressed mood, and perseveration of thought. Neurobehavioral deficits accumulate across days of partial sleep loss to levels equivalent to those found after 1 to 3 nights of total sleep loss. Recent experiments reveal that following days of chronic restriction of sleep duration below 7 hours per night, significant daytime cognitive dysfunction accumulates to levels comparable to that found after severe acute total sleep deprivation. Additionally, individual variability in neurobehavioral responses to sleep restriction appears to be stable, suggesting a trait-like (possibly genetic) differential vulnerability or compensatory changes in the neurobiological systems involved in cognition. A causal role for reduced sleep duration in adverse health outcomes remains unclear, but laboratory studies of healthy adults subjected to sleep restriction have found adverse effects on endocrine functions, metabolic and inflammatory responses, suggesting that sleep restriction produces physiological consequences that may be unhealthy.

  17. Regulatory physiology discipline science plan

    Science.gov (United States)

    1991-01-01

    The focus of the Regulatory Physiology discipline of the Space Physiology and Countermeasures Program is twofold. First, to determine and study how microgravity and associated factors of space flight affect the regulatory mechanisms by which humans adapt and achieve homeostasis and thereby regulate their ability to respond to internal and external signals; and, second, to study selected physiological systems that have been demonstrated to be influenced by gravity. The Regulatory Physiology discipline, as defined here, is composed of seven subdisciplines: (1) Circadian Rhythms, (2) Endocrinology, (3) Fluid and Electrolyte Regulation, (4) Hematology, (5) Immunology, (6) Metabolism and Nutrition, and (7) Temperature Regulation. The purpose of this Discipline Science Plan is to provide a conceptual strategy for NASA's Life Sciences Division research and development activities in the area of regulatory physiology. It covers the research areas critical to NASA's programmatic requirements for the Extended-Duration Orbiter, Space Station Freedom, and exploration mission science activities. These science activities include ground-based and flight; basic, applied, and operational; and animal and human research and development. This document summarizes the current status of the program, outlines available knowledge, establishes goals and objectives, identifies science priorities, and defines critical questions in regulatory physiology. It contains a general plan that will be used by both NASA Headquarters Program Offices and the field centers to review and plan basic, applied, and operational intramural and extramural research and development activities in this area.

  18. Water in the physiology of plant: thermodynamics and kinetic

    Directory of Open Access Journals (Sweden)

    Maurizio Cocucci

    2011-02-01

    Full Text Available Molecular properties of water molecule determine its role in plant physiology. At molecular level the properties of water molecules determine the behaviour of other plant molecules; in particular its physic characteristics are important in the operativeness of macromolecules and in plant thermoregulation. Plant water supply primarily dependent on thermodynamics properties in particular water chemical potential and its components, more recently there are evidences that suggest an important role in the water kinetic characteristics, depending, at cell membrane level, in particular plasmalemma, on the presence of specific water channel, the aquaporines controlled in its activity by a number of physiological and biochemical factors. Thermodynamics and kinetic factors controlled by physiological, biochemical properties and molecular effectors, control water supply and level in plants to realize their survival, growth and differentiation and the consequent plant production.

  19. The physiology of growth hormone and sport.

    LENUS (Irish Health Repository)

    Widdowson, W Matthew

    2012-02-01

    The growth hormone (GH)\\/ insulin-like growth factor-I (IGF-I) axis exerts short-and long-term metabolic effects that are potentially important during exercise. Exercise is a potent stimulus to GH release and there is some evidence that the acute increase in GH is important in regulating substrate metabolism post-exercise. Regular exercise also increases 24-hour GH secretion rates, which potentially contributes to the physiologic changes induced by training. The effects of GH replacement in GH-deficient adults provide a useful model with which to study the effects of the more long-term effects of the GH\\/ IGF-I axis. There is convincing evidence that GH replacement increases exercise capacity. Measures of exercise performance including maximal oxygen uptake (VO2max) and ventilatory threshold (VeT) are impaired in GH deficiency and improved by GH replacement, probably through some combination of increased oxygen delivery to exercising muscle, increased fatty acid availability with glycogen sparing, increased muscle strength, improved body composition and improved thermoregulation. Administration of supraphysiologic doses of GH to athletes increases fatty acid availability and reduces oxidative protein loss particularly during exercise, and increases lean body mass. It is not known whether these effects translate to improved athletic performance, although recombinant human GH is known to be widely abused in sport. The model of acromegaly provides evidence that long-term GH excess does not result in improved performance but it is possible that a "window" exists in which the protein anabolic effects of supraphysiologic GH might be advantageous.

  20. The Effect of Recovery Duration on Vastus Lateralis Oxygenation, Heart Rate, Perceived Exertion and Time Motion Descriptors during Small Sided Football Games.

    Directory of Open Access Journals (Sweden)

    Scott McLean

    Full Text Available Small sided games (SSG of football are an effective and efficient format to simultaneously train the physiological, technical, and tactical components of football. The duration of the recovery period between bouts of SSG will affect the physiological response to subsequent bouts. It was hypothesised that decreasing the duration of recovery periods separating serial SSG bouts would increase physiological, and perceptual responses, and decrease high speed running, and distance during SSG bouts.Twelve experienced footballers (mean ± SD; age 21 ± 3 yrs; VO2peak 64 ± 7 ml·min·kg-1; playing experience 15 ± 3 yrs completed two SSG sessions. Each SSG consisted of 3 vs. 3 players and 6 bouts of 2 min duration, with bouts separated by either 30 s recovery (REC-30 or 120 s recovery (REC-120. Deoxygenated haemoglobin (HHb in the vastus lateralis (VL (using near infrared spectroscopy, heart rate (HR and time motion descriptors (TMD (speed and distance were measured continuously during the SSG sessions and perceived exertion (RPE was measured for each bout.During the recovery periods, in REC-30 compared to REC-120, there was a significant (p < 0.05 main effect of a higher HHb and HR. During the bouts, in REC-30 compared to REC-120, there were no significant differences in HHb, HR, RPE, or TMD, but within both REC-30 and REC-120 there were significant increases as a function of bout number in RPE.Although a four-fold increase in recovery period allowed a significant increase in the recovery of HHb and HR, this did not increase the physiological, and perceptual responses, or time motion descriptors during the bouts. These results could have been due to the regulation of effort (pacing, in these experienced players performing an exercise task to which they were well adapted.

  1. Epidemiology of exertional rhabdomyolysis susceptibility in standardbred horses reveals associated risk factors and underlying enhanced performance.

    Directory of Open Access Journals (Sweden)

    Cajsa M Isgren

    Full Text Available BACKGROUND: Exertional rhabdomyolysis syndrome is recognised in many athletic horse breeds and in recent years specific forms of the syndrome have been identified. However, although Standardbred horses are used worldwide for racing, there is a paucity of information about the epidemiological and performance-related aspects of the syndrome in this breed. The objectives of this study therefore were to determine the incidence, risk factors and performance effects of exertional rhabdomyolysis syndrome in Standardbred trotters and to compare the epidemiology and genetics of the syndrome with that in other breeds. METHODOLOGY/PRINCIPAL FINDINGS: A questionnaire-based case-control study (with analysis of online race records was conducted following identification of horses that were determined susceptible to exertional rhabdomyolysis (based on serum biochemistry from a total of 683 horses in 22 yards. Thirty six exertional rhabdomyolysis-susceptible horses were subsequently genotyped for the skeletal muscle glycogen synthase (GYS1 mutation responsible for type 1 polysaccharide storage myopathy. A total of 44 susceptible horses was reported, resulting in an annual incidence of 6.4 (95% CI 4.6-8.2% per 100 horses. Female horses were at significantly greater risk than males (odds ratio 7.1; 95% CI 2.1-23.4; p = 0.001 and nervous horses were at a greater risk than horses with calm or average temperaments (odds ratio 7.9; 95% CI 2.3-27.0; p = 0.001. Rhabdomyolysis-susceptible cases performed better from standstill starts (p = 0.04 than controls and had a higher percentage of wins (p = 0.006. All exertional rhabdomyolysis-susceptible horses tested were negative for the R309H GYS1 mutation. CONCLUSIONS/SIGNIFICANCE: Exertional rhabdomyolysis syndrome in Standardbred horses has a similar incidence and risk factors to the syndrome in Thoroughbred horses. If the disorder has a genetic basis in Standardbreds, improved performance in susceptible animals may be

  2. Modeling trajectories of perceived leg exertion during maximal cycle ergometer exercise in children and adolescents.

    Science.gov (United States)

    Huebner, Marianne; Zhang, Zhen; Therneau, Terry; McGrath, Patrick; Pianosi, Paolo

    2014-01-09

    Borg developed scales for rating pain and perceived exertion in adults that have also been used in pediatric populations. Models describing functional relationships between perceived exertion and work capacity have not been studied in children. We compared different models and their fits to individual trajectories and assessed the variability in these trajectories. Ratings of perceived exertion (RPE) were collected from 79 children. Progressive cycle ergonometric testing was performed to maximal work capacity with test duration ranging from 6- 12 minutes. Ratings were obtained during each 1-minute increment. Work was normalized to individual maximal work capacity (Wmax). A delay was defined as the fraction of Wmax at which point an increase in ratings of leg fatigue occurred. Such a delay term allows the characterization of trajectories for children whose ratings were initially constant with increasing work. Two models were considered, a delay model and a power model that is commonly used to analyze Borg ratings. Individual model fit was assessed with root mean squared error (RMSE). Functional clustering algorithms were used to identify patterns. Leg tiredness developed quickly for some children while for others there was a delay before an in- creased ratings of leg exertion occurred with increasing work. Models for individual trajectories with the smallest RMSE included a delay and a quadratic term (quadratic-delay model), or a power function and a delay term (power-delay model) compared to a simple power function. The median delay was 40% Wmax (interquartile range (IQR): 26-49%) in a quadratic-delay model, while the median exponent was 1.03 (IQR: 0.83-1.78) in a power-delay model. Nine clusters were identified showing linear or quadratic patterns with or without a delay. Cluster membership did not depend on age, gender or diagnosis. Children and adolescents vary widely in their capacity to rate their perceptions and exhibit different functional relationships

  3. Conservation physiology of animal migration

    Science.gov (United States)

    Lennox, Robert J.; Chapman, Jacqueline M.; Souliere, Christopher M.; Tudorache, Christian; Wikelski, Martin; Metcalfe, Julian D.; Cooke, Steven J.

    2016-01-01

    Migration is a widespread phenomenon among many taxa. This complex behaviour enables animals to exploit many temporally productive and spatially discrete habitats to accrue various fitness benefits (e.g. growth, reproduction, predator avoidance). Human activities and global environmental change represent potential threats to migrating animals (from individuals to species), and research is underway to understand mechanisms that control migration and how migration responds to modern challenges. Focusing on behavioural and physiological aspects of migration can help to provide better understanding, management and conservation of migratory populations. Here, we highlight different physiological, behavioural and biomechanical aspects of animal migration that will help us to understand how migratory animals interact with current and future anthropogenic threats. We are in the early stages of a changing planet, and our understanding of how physiology is linked to the persistence of migratory animals is still developing; therefore, we regard the following questions as being central to the conservation physiology of animal migrations. Will climate change influence the energetic costs of migration? Will shifting temperatures change the annual clocks of migrating animals? Will anthropogenic influences have an effect on orientation during migration? Will increased anthropogenic alteration of migration stopover sites/migration corridors affect the stress physiology of migrating animals? Can physiological knowledge be used to identify strategies for facilitating the movement of animals? Our synthesis reveals that given the inherent challenges of migration, additional stressors derived from altered environments (e.g. climate change, physical habitat alteration, light pollution) or interaction with human infrastructure (e.g. wind or hydrokinetic turbines, dams) or activities (e.g. fisheries) could lead to long-term changes to migratory phenotypes. However, uncertainty remains

  4. The endocannabinoid N-arachidonoyldopamine (NADA) exerts neuroprotective effects after excitotoxic neuronal damage via cannabinoid receptor 1 (CB(1)).

    Science.gov (United States)

    Grabiec, Urszula; Koch, Marco; Kallendrusch, Sonja; Kraft, Robert; Hill, Kerstin; Merkwitz, Claudia; Ghadban, Chalid; Lutz, Beat; Straiker, Alex; Dehghani, Faramarz

    2012-03-01

    Endocannabinoids exert numerous effects in the CNS under physiological and pathological conditions. The aim of the present study was to examine whether the endocannabinoid N-arachidonoyldopamine (NADA) may protect neurons in excitotoxically lesioned organotypic hippocampal slice cultures (OHSC). OHSC were excitotoxically lesioned by application of N-methyl-d-aspartate (NMDA, 50 μM) for 4 h and subsequently treated with different NADA concentrations (0.1 pM-50 μM) alone or in combination with cannabinoid receptor antagonists. NADA protected dentate gyrus granule cells and caused a slight reduction in the number of microglial cells. The number of degenerated neurons significantly decreased between 100 pM and 10 μM NADA (p NADA mediated neuroprotection, we applied the cannabinoid (CB) receptor 1 (CB(1)) inverse agonist/antagonist AM251, CB(2) inverse agonist/antagonist AM630, abnormal-cannabidiol (abn-CBD)-sensitive receptor antagonist O-1918, transient receptor potential channel V1 (TRPV1) antagonist 6-iodonordihydrocapsaicin and A1 (TRPA1) antagonist HC-030031. Neuroprotective properties of low (1 nM) but not high (10 μM) NADA concentrations were solely blocked by AM251 and were absent in CB(1)(-/-) mice. AM630, O-1918, 6-iodonordihydrocapsaicin and HC-030031 showed no effects at all NADA concentrations applied. Our findings demonstrate that NADA protects dentate gyrus granule cells by acting via CB(1). NADA reduced the number of microglial cells at distinct concentrations. TRPV1 and TRPA1 were not involved in NADA mediated neuroprotection. Thus, our data implicate that NADA mediated activation of neuronal CB(1) may serve as a novel pharmacological target to mitigate symptoms of neuronal damage. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. A Transdisciplinary Model Integrating Genetic, Physiological, and Psychological Correlates of Voluntary Exercise

    Science.gov (United States)

    Bryan, Angela; Hutchison, Kent E.; Seals, Douglas R.; Allen, David L.

    2007-01-01

    Objective Physical inactivity contributes to as many as 250,000 premature deaths per year (R. R. Pate et al., 1995). The authors’ objective was to test a transdisciplinary model of the ways in which genetic variants, physiological factors, and psychological factors are thought to influence exercise with 64 healthy, regular exercisers. Design In a within-subjects design, psychological and physiological responses to exercise were compared with responses to a sedentary activity. Main Outcome Measures The authors measured affective state, perceived exertion, heart rate, and temperature change in response to moderate exercise versus sedentary activity. They also quantified genotypes on a single nucleotide polymorphism in the brain-derived neurotrophic factor (BDNF) gene. Results and Conclusions The data show a relation between increases in positive affective states and acute exercise behavior, as opposed to a sedentary control. The BDNF gene moderated the effect of exercise on mood, heart rate, and perceived exertion. Physiological factors were, in turn, related to mood response, and mood response was a significant correlate of motivation to exercise in the future and of current exercise behavior. The model has potential as a framework for the basic study of the genetic, physiological, and psychological processes involved with voluntary exercise and as a tool for the applied examination of tailored exercise interventions and their efficacy for different subsets of individuals. PMID:17209695

  6. Diagnosis and Treatment of Chronic Exertional Compartment Syndrome - a Proposition for an Algorithm

    DEFF Research Database (Denmark)

    Larsen, Peter Birk; Jensen, Steffen Skov

    Title: Diagnosis and treatment of chronic exertional compartment syndrome - a proposition for an algorithm based on case series of patients treated at Sports Medicine Division, Department of Orthopaedic Surgery, Viborg Regional Hospital, Denmark Background: Chronic exertional compartment syndrome...... that specific activity induced strain (SAIS) can be used to diagnose the specific affected compartments, and in this way be able to safely and effectively treat this disorder using endoscopic assisted selective fasciotomy (EASF). Materials and Methods: Retrospective follow-up study of 13 consecutive selected...... in conjunction with a thorough medical history formed the basis for the diagnosis. Results: 11 patients were offered surgical treatment consisting of EASF of the affected compartment (10 bilateral and 1 unilateral, 8 affected in specific compartments and 3 affected in all compartments. Only 1 patient required...

  7. Virtual Exertions: a user interface combining visual information, kinesthetics and biofeedback for virtual object manipulation.

    Science.gov (United States)

    Ponto, Kevin; Kimmel, Ryan; Kohlmann, Joe; Bartholomew, Aaron; Radwin, Robert G

    2012-01-01

    Virtual Reality environments have the ability to present users with rich visual representations of simulated environments. However, means to interact with these types of illusions are generally unnatural in the sense that they do not match the methods humans use to grasp and move objects in the physical world. We demonstrate a system that enables users to interact with virtual objects with natural body movements by combining visual information, kinesthetics and biofeedback from electromyograms (EMG). Our method allows virtual objects to be grasped, moved and dropped through muscle exertion classification based on physical world masses. We show that users can consistently reproduce these calibrated exertions, allowing them to interface with objects in a novel way.

  8. Chronic exertional compartment syndrome of the forearm: a case series of 12 patients treated with fasciotomy.

    Science.gov (United States)

    Brown, J S; Wheeler, P C; Boyd, K T; Barnes, M R; Allen, M J

    2011-06-01

    Chronic exertional compartment syndrome of the forearm is rare in the published literature. We report the outcome of a series of 12 patients treated with fasciotomy over a 14 year period. All patients underwent dynamic intra-compartmental pressure testing using a slit catheter technique before surgery. Raised intra-compartmental pressures on exercise, typical symptoms and the absence of other diagnoses were criteria for offering surgical intervention. The superficial flexor, deep flexor and extensor compartments were released. Median follow-up was 9.5 years (range 7 months to 12 years). Median patient-reported percentage improvement after surgery was 88% (range 0%-100%). Median time to return to full activity was 9 weeks. Eleven out of 12 patients were satisfied, very satisfied or extremely satisfied with the outcome of surgery. Fasciotomy can be an effective treatment for chronic exertional compartment syndrome of the forearm.

  9. Incidental Finding of Inferior Vena Cava Atresia Presenting with Deep Venous Thrombosis following Physical Exertion

    Directory of Open Access Journals (Sweden)

    Shalini Koppisetty

    2015-01-01

    Full Text Available Inferior vena cava atresia (IVCA is a rare but well described vascular anomaly. It is a rare risk factor for deep venous thrombosis (DVT, found in approximately 5% of cases of unprovoked lower extremity (LE DVT in patients <30 years of age. Affected population is in the early thirties, predominantly male, often with a history of major physical exertion and presents with extensive or bilateral DVTs. Patients with IVC anomalies usually develop compensatory circulation through the collateral veins with enlarged azygous/hemizygous veins. Despite the compensatory circulation, the venous drainage of the lower limbs is often insufficient leading to venous stasis and thrombosis. We describe a case of extensive and bilateral deep venous thrombosis following physical exertion in a thirty-six-year-old male patient with incidental finding of IVCA on imaging.

  10. Exertional rhabdomyolysis and acute renal failure following the Army Physical Fitness Test.

    Science.gov (United States)

    Tietjen, D P; Guzzi, L M

    1989-01-01

    Rhabdomyolysis and myoglobinuric acute renal failure may occur following strenuous exercise and may be more common in less physically conditioned persons. A case of moderately severe acute renal failure after the exercise involved in a routine Army Physical Fitness Test (APFT) is described. This level of exertion, which is universally applied to Army personnel, should be recognized as a potential etiology of rhabdomyolysis. Prospective studies may help define the exact risk to renal function provided by the APFT.

  11. Salivary Gland Derived BDNF Overexpression in Mice Exerts an Anxiolytic Effect

    OpenAIRE

    Saruta, Juri; To, Masahiro; Sugimoto, Masahiro; Yamamoto, Yuko; Shimizu, Tomoko; Nakagawa, Yusuke; Inoue, Hiroko; Saito, Ichiro; Tsukinoki, Keiichi

    2017-01-01

    Brain-derived neurotrophic factor (BDNF) is abundant in the hippocampus and plays critical roles in memory and synapse formation, as well as exerting antidepressant-like effects in psychiatric disorders. We previously reported that BDNF is expressed in salivary glands and affects blood BDNF content. However, the function of salivary BDNF remains unclear. The aim of this study was to generate transgenic mice overexpressing BDNF in the salivary glands. Hence, we used the Lama construct (hemaggl...

  12. Fatigue Induced by Physical and Mental Exertion Increases Perception of Effort and Impairs Subsequent Endurance Performance

    OpenAIRE

    Pageaux, Benjamin; Lepers, Romuald

    2016-01-01

    Endurance performance involves the prolonged maintenance of constant or self-regulated power/velocity or torque/force. While the impact of numerous determinants of endurance performance has been previously reviewed, the impact of fatigue on subsequent endurance performance still needs to be documented. This review aims to present the impact of fatigue induced by physical or mental exertion on subsequent endurance performance. For the purpose of this review, endurance performance refers to per...

  13. Effect of Stimulant Medication Use by Children with ADHD on Heart Rate and Perceived Exertion

    Science.gov (United States)

    Mahon, Anthony D.; Woodruff, Megan E.; Horn, Mary P.; Marjerrison, Andrea D.; Cole, Andrew S.

    2012-01-01

    The effect of stimulant medication use by children with attention deficit/hyperactivity disorder (ADHD) on the rating of perceived exertion (RPE)--heart rate (HR) relationship was examined. Children with ADHD (n = 20; 11.3 [plus or minus] 1.8 yrs) and children without ADHD (n = 25; 11.2 [plus or minus] 2.1 yrs) were studied. Children with ADHD…

  14. Implicit theories about willpower predict the activation of a rest goal following self-control exertion.

    Science.gov (United States)

    Job, Veronika; Bernecker, Katharina; Miketta, Stefanie; Friese, Malte

    2015-10-01

    Past research indicates that peoples' implicit theories about the nature of willpower moderate the ego-depletion effect. Only people who believe or were led to believe that willpower is a limited resource (limited-resource theory) showed lower self-control performance after an initial demanding task. As of yet, the underlying processes explaining this moderating effect by theories about willpower remain unknown. Here, we propose that the exertion of self-control activates the goal to preserve and replenish mental resources (rest goal) in people with a limited-resource theory. Five studies tested this hypothesis. In Study 1, individual differences in implicit theories about willpower predicted increased accessibility of a rest goal after self-control exertion. Furthermore, measured (Study 2) and manipulated (Study 3) willpower theories predicted an increased preference for rest-conducive objects. Finally, Studies 4 and 5 provide evidence that theories about willpower predict actual resting behavior: In Study 4, participants who held a limited-resource theory took a longer break following self-control exertion than participants with a nonlimited-resource theory. Longer resting time predicted decreased rest goal accessibility afterward. In Study 5, participants with an induced limited-resource theory sat longer on chairs in an ostensible product-testing task when they had engaged in a task requiring self-control beforehand. This research provides consistent support for a motivational shift toward rest after self-control exertion in people holding a limited-resource theory about willpower. (c) 2015 APA, all rights reserved).

  15. Prevention of Organ Injury in Exertional Heat Stroke: Preclinical Evaluation of a New Class of NSAIDs

    Science.gov (United States)

    2017-10-01

    Mustico DL, Haines JM, and Clanton TL. Biomarkers of multi- organ injury in a pre-clinical model of exertional heat stroke. Journal of Applied...Human Performance, The University of Florida; and 2Thermal and Mountain Medicine Division, United States Army Research Institute of Environmental...hypovolemic circulatory collapse by IL-6 activated Stat3. PLoS One 3: e1605, 2008. doi:10.1371/ journal . pone.0001605. 3. Bachmaier K, Toya S, Malik AB

  16. Chronic exertional compartment syndrome of the forearm: a case series of 12 patients treated with fasciotomy

    OpenAIRE

    Brown, J S; Wheeler, P C; Boyd, K T; Barnes, M R; Allen, M J

    2011-01-01

    Chronic exertional compartment syndrome of the forearm is rare in the published literature. We report the outcome of a series of 12 patients treated with fasciotomy over a 14 year period. All patients underwent dynamic intra-compartmental pressure testing using a slit catheter technique before surgery. Raised intra-compartmental pressures on exercise, typical symptoms and the absence of other diagnoses were criteria for offering surgical intervention. The superficial flexor, deep flexor and e...

  17. Bifidobacterium strains from resident infant human gastrointestinal microflora exert antimicrobial activity

    OpenAIRE

    Lievin, V; Peiffer, I.; Hudault, S; Rochat, F; Brassart, D; Neeser, J.P.; Servin, A L

    2000-01-01

    BACKGROUND AND AIMS—The gastrointestinal microflora exerts a barrier effect against enteropathogens. The aim of this study was to examine if bifidobacteria, a major species of the human colonic microflora, participates in the barrier effect by developing antimicrobial activity against enterovirulent bacteria.
METHODS—Antibacterial activity was examined in vitro against a wide range of Gram negative and Gram positive pathogens. Inhibition of Salmonella typhimurium SL1334 cell association and c...

  18. The Influence of a Bout of Exertion on Novice Barefoot Running Dynamics

    Directory of Open Access Journals (Sweden)

    Rami Hashish, Sachithra D. Samarawickrame, Lucinda Baker, George J. Salem

    2016-06-01

    Full Text Available Barefoot, forefoot strike (FFS running has recently risen in popularity. Relative to shod, rear-foot strike (RFS running, employing a FFS is associated with heightened triceps surae muscle activation and ankle mechanical demand. Novice to this pattern, it is plausible that habitually shod RFS runners exhibit fatigue to the triceps surae when acutely transitioning to barefoot running, thereby limiting their ability to attenuate impact. Therefore, the purpose was to determine how habitually shod RFS runners respond to an exertion bout of barefoot running, operationally defined as a barefoot run 20% of mean daily running distance. Twenty-one RFS runners performed novice barefoot running, before and after exertion. Ankle peak torque, triceps surae EMG median frequency, foot-strike patterns, joint energy absorption, and loading rates were evaluated. Of the 21 runners, 6 maintained a RFS, 10 adopted a mid-foot strike (MFS, and 5 adopted a FFS during novice barefoot running. In-response to exertion, MFS and FFS runners demonstrated reductions in peak torque, median frequency, and ankle energy absorption, and an increase in loading rate. RFS runners demonstrated reductions in peak torque and loading rate. These results indicate that a short bout of running may elicit fatigue to novice barefoot runners, limiting their ability to attenuate impact.

  19. Defining the Focus of Attention: Effects of Attention on Perceived Exertion and Fatigue

    Science.gov (United States)

    Lohse, Keith R.; Sherwood, David E.

    2011-01-01

    This manuscript presents two experiments designed to explore the effects of attention on perceived exertion and time to failure in a fatiguing athletic task. There were two major motivating factors for these experiments. First, there are few studies evaluating attentional focus effects in endurance tasks and, second, there is a lack of integration between studies of attentional focus as external/internal (e.g., Wulf, 2007a) compared to associative/dissociative (e.g., Stevinson and Biddle, 1998). In Experiment 1, we used a fatiguing wall-sit posture (essentially a complex, isometric task) to compare two different types of external attention with an internal focus on the position of the legs. An external focus (regardless of type) increased the time taken to failure and reduced perceived exertion. In Experiment 2, we manipulated subjects’ expectancy of fatigue to test the interaction of attention and expectancy (both top-down factors) in this highly fatiguing task. Previous theories of attention during endurance tasks have suggested that as fatigue/pain increase, bottom-up factors begin to dominate subjects’ attention. While this may be true, Experiment 2 showed that even in a highly fatiguing task, attentional strategies, and expectancies affected the time to failure and perceived exertion. PMID:22102843

  20. Exertional Myopathy in a Juvenile Green Sea Turtle (Chelonia mydas Entangled in a Large Mesh Gillnet

    Directory of Open Access Journals (Sweden)

    Brianne E. Phillips

    2015-01-01

    Full Text Available A juvenile female green sea turtle (Chelonia mydas was found entangled in a large mesh gillnet in Pamlico Sound, NC, and was weak upon presentation for treatment. Blood gas analysis revealed severe metabolic acidosis and hyperlactatemia. Plasma biochemistry analysis showed elevated aspartate aminotransferase and creatine kinase, marked hypercalcemia, hyperphosphatemia, and hyperkalemia. Death occurred within 24 hours of presentation despite treatment with intravenous and subcutaneous fluids and sodium bicarbonate. Necropsy revealed multifocal to diffuse pallor of the superficial and deep pectoral muscles. Mild, multifocal, and acute myofiber necrosis was identified by histopathological examination. While histological changes in the examined muscle were modest, the acid-base, mineral, and electrolyte abnormalities were sufficiently severe to contribute to this animal’s mortality. Exertional myopathy in reptiles has not been well characterized. Sea turtle mortality resulting from forced submergence has been attributed to blood gas derangements and seawater aspiration; however, exertional myopathy may also be an important contributing factor. If possible, sea turtles subjected to incidental capture and entanglement that exhibit weakness or dull mentation should be clinically evaluated prior to release to minimize the risk of delayed mortality. Treatment with appropriate fluid therapy and supportive care may mitigate the effects of exertional myopathy in some cases.

  1. An Exploration of Exertion in Mixed Reality Systems via the ``Table Tennis for Three'' Game

    Science.gov (United States)

    Mueller, Florian ‘Floyd'; Gibbs, Martin R.; Vetere, Frank

    Humans experience their physical and social environment through their bodies and their associated movement actions. However, most mixed reality systems approach the integration of the real with a virtual world from a computational perspective, often neglecting the body’s capabilities by offering only limited interaction possibilities with a few augmented tangible objects. We propose a view on mixed reality systems that focuses on the human body and its movements, because we believe such an approach has the potential to support novel interaction experiences, as explored by a prototypal gaming system that was inspired by exertion actions exhibited in table tennis. “Table Tennis for Three” enables augmented bodily experiences while offering new opportunities for interaction, such as supporting three players simultaneously across geographical distances. This case study offers an exploration of the role of the human body and its associated movement actions in mixed reality systems, aiming to contribute toward an understanding of the use of exertion in such systems. Such an understanding can support leveraging the many benefits of exertion through mixed reality systems and therefore guide future advances in this research field.

  2. Single minimal incision fasciotomy for chronic exertional compartment syndrome of the lower leg.

    Science.gov (United States)

    Maffulli, Nicola; Loppini, Mattia; Spiezia, Filippo; D'Addona, Alessio; Maffulli, Gayle D

    2016-05-24

    Chronic exertional compartment syndrome (CECS) involves a painful increase in compartment pressure caused by exercise and relieved by rest, common in athletes. The most common site for CECS in the lower limbs is the anterior leg compartment. The aim of this study is to evaluate the outcomes of a single minimal incision fasciotomy in athletes and their capability to return to high level sport activity. The study reports mid-term results in a series of 18 consecutive athletes with chronic exertional compartment syndrome of the leg who had undergone minimally invasive fasciotomy. Between 2000 and 2007, we prospectively enrolled 18 consecutive athletes (12 males and six females, median age 27 years) with unilateral or bilateral chronic exertional compartment syndrome undergoing unilateral or bilateral minimally invasive fasciotomy. Clinical outcomes were assessed with Short-Form Health Survey-36 (SF-36) and European Quality of Life-5 Dimension (EQ-5D) scale. The ability to participate in sport before and after surgery and the time to return to training (RTT) and to sport (RTS) were recorded. The median follow-up after surgery was 36 months. Both questionnaires showed a statistically significant improvement (P compartment syndrome of the anterior and lateral compartments of the leg with good results in the mid-term.

  3. Selective Fasciotomy for Chronic Exertional Compartment Syndrome Detected With Exercise Magnetic Resonance Imaging.

    Science.gov (United States)

    Park, Sehan; Lee, Ho Seong; Seo, Sang Gyo

    2017-11-01

    Chronic exertional compartment syndrome that is refractory to conservative management should be treated with surgical fasciotomy. However, owing to the limitations of intracompartmental needle manometry in reaching a definite diagnosis, the appropriate timing for fasciotomy and on which compartment remain unclear. The authors report the case of a 22-year-old male military cadet who reported pain in his left calf when running or walking for long distances. The pain was located at the lateral aspect of the calf, from the mid-calf level to the ankle. At another hospital, nonenhanced magnetic resonance imaging had been performed, which showed no considerable abnormality. The authors used exercise magnetic resonance imaging to diagnose chronic exertional compartment syndrome. They performed selective fasciotomy on the compartment that showed a high signal intensity. As a military cadet, the patient was required to jog for more than an hour per day and perform strenuous muscle exercises. He reported that he did not have calf pain or discomfort during such activities 13 months postoperatively. The authors obtained a follow-up exercise magnetic resonance image. Compared with the preoperative magnetic resonance image, the follow-up exercise magnetic resonance image did not show high signal intensity at the lateral compartment. Exercise magnetic resonance imaging is useful in confirming the diagnosis of chronic exertional compartment syndrome and enables the performance of selective fasciotomy on the affected compartment. [Orthopedics. 2017; 40(6):e1099-e1102.]. Copyright 2017, SLACK Incorporated.

  4. Relative contribution of trunk muscles to the stability of the lumbar spine during isometric exertions.

    Science.gov (United States)

    Cholewicki, Jacek; VanVliet, James J

    2002-02-01

    To compare the relative contribution of various trunk muscles to the stability of the lumbar spine. Quantification of spine stability with a biomechanical model. Modern low back rehabilitation techniques focus on muscles that stabilize the lumbar spine. However, the relative contribution of various trunk muscles to spine stability is currently unknown. Eight male subjects performed isometric exertions in trunk flexion, extension, lateral bending, and axial rotation, and isometric exertions under vertical trunk loading and in a lifting hold. Each isometric trial was repeated three times at 20%, 40%, and 60% of the maximum trunk flexion force or with a load of 0%, 20%, 40%, and 60% of body weight for the latter two exertions. Surface EMG data from 12 major trunk muscles were used in the biomechanical model to estimate stability of the lumbar spine. A simulation of each trial was performed repeatedly with one of the 10 major trunk muscle groups removed from the model. Relative contribution of each muscle to spine stability was significantly affected by the combination of loading magnitude and direction (3-way interaction). None of the removed muscles reduced spine stability by more than 30%. A single muscle cannot be identified as the most important for the stability of the lumbar spine. Rather, spine stability depends on the relative activation of all trunk muscles and other loading variables. This study will improve our understanding of individual trunk muscles' contribution to overall stability of the lumbar spine.

  5. Defining the Focus of Attention: Effects of Attention on Perceived Exertion and Fatigue.

    Directory of Open Access Journals (Sweden)

    Keith eLohse

    2011-11-01

    Full Text Available This manuscript presents two experiments designed to explore the effects of attention on perceived exertion and time to failure in a fatiguing athletic task. There were two major motivating factors for these experiments. First, there are few studies evaluating attentional focus effects in endurance tasks and, second, there is a lack of integration between studies of attentional focus as external/internal (e.g., Wulf, 2007 compared to associative/dissociative (e.g., Stevenson & Biddle, 1998. In Experiment 1, we used a fatiguing wall-sit posture (essentially a complex, isometric task to compare two different types of external attention with an internal focus on the position of the legs. An external focus (regardless of type increased the time taken to failure and reduced perceived exertion. In Experiment 2, we manipulated subjects’ expectancy of fatigue to test the interaction of attention and expectancy (both top-down factors in this highly fatiguing task. Previous theories of attention during endurance tasks have suggested that as fatigue/pain increase, bottom-up factors begin to dominate subjects’ attention. While this may be true, Experiment 2 showed that even in a highly fatiguing task, attentional strategies and expectancies affected the time to failure and perceived exertion.

  6. Dalhousie Dyspnea and perceived exertion scales: psychophysical properties in children and adolescents.

    Science.gov (United States)

    Pianosi, Paolo T; Huebner, Marianne; Zhang, Zhen; McGrath, Patrick J

    2014-08-01

    Children and adolescents vary widely in their perception of, or capacity to rate, sensations during exercise using the Borg scale. We sought to measure sensory-perceptual responses obtained using Dalhousie Dyspnea and Perceived Exertion Scales in 79 pediatric subjects during maximal exercise challenge and to determine the psychophysical function relationship(s). Concurrent validity was assessed by canonical plots of mean ratings on either scale, which showed showing very good correlations for perceived leg exertion vs work, and dyspnea vs ventilation. Both scales yielded similar results with respect to goodness of fit regardless of whether data was fitted to a power or quadratic function provided a delay term was included. The quadratic model fixed the exponent of the power law at 2 but, unlike a power model, allowed characterization of individual responses that increased and then plateaued. Dalhousie Dyspnea and Perceived Exertion Scales offer an alternative to Borg scale during exercise in pediatric populations. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Physiologic effects of bowel preparation

    DEFF Research Database (Denmark)

    Holte, Kathrine; Nielsen, Kristine Grubbe; Madsen, Jan Lysgård

    2004-01-01

    PURPOSE: Despite the universal use of bowel preparation before colonoscopy and colorectal surgery, the physiologic effects have not been described in a standardized setting. This study was designed to investigate the physiologic effects of bowel preparation. METHODS: In a prospective study, 12...... healthy volunteers (median age, 63 years) underwent bowel preparation with bisacodyl and sodium phosphate. Fluid and food intake were standardized according to weight, providing adequate calorie and oral fluid intake. Before and after bowel preparation, weight, exercise capacity, orthostatic tolerance...... preparation has significant adverse physiologic effects, which may be attributed to dehydration. The majority of these findings is small and may not be of clinical relevance in otherwise healthy patients undergoing bowel preparation and following recommendations for oral fluid intake....

  8. Centrifuges in gravitational physiology research

    Science.gov (United States)

    Ballard, Rodney W.; Davies, Phil; Fuller, Charles A.

    1993-01-01

    Data from space flight and ground based experiments have clearly demonstrated the importance of Earth gravity for normal physiological function in man and animals. Gravitational Physiology is concerned with the role and influence of gravity on physiological systems. Research in this field examines how we perceive and respond to gravity and the mechanisms underlying these responses. Inherent in our search for answers to these questions is the ability to alter gravity, which is not physically possible without leaving Earth. However, useful experimental paradigms have been to modify the perceived force of gravity by changing either the orientation of subjects to the gravity vector (i.e., postural changes) or by applying inertial forces to augment the magnitude of the gravity vector. The later technique has commonly been used by applying centripetal force via centrifugation.

  9. 49 CFR 1103.13 - Attempts to exert political or personal influence on the Board are prohibited.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 8 2010-10-01 2010-10-01 false Attempts to exert political or personal influence... Attempts to exert political or personal influence on the Board are prohibited. (a) It is unethical for a practitioner to attempt to influence the judgment of the Board by threats of political or personal reprisal. (b...

  10. Stimulating Student Interest in Physiology: The Intermedical School Physiology Quiz

    Science.gov (United States)

    Cheng, Hwee-Ming

    2010-01-01

    The Intermedical School Physiology Quiz (IMSPQ) was initiated in 2003 during the author's last sabbatical from the University of Malaya. At this inaugural event, there were just seven competing teams from Malaysian medical schools. The challenge trophy for the IMSPQ is named in honor of Prof. A. Raman, who was the first Malaysian Professor of…

  11. From Physiology to Prevention: Further remarks on a physiological imperative

    Directory of Open Access Journals (Sweden)

    B Jouanjean

    2012-05-01

    Full Text Available Physiology, is the fundamental and functional expression of life. It is the study of all the representative functions of Man in all his capacities, and in particular, his capacity to work. It is very possible to establish a link between a physiological and physiopathological state, the capacity of work and the economy, which can be understood as the articulation between the physiological capacities of Man and the production of work. If these functions are innately acquired by Man they are likewise maintained by regulatory functions throughout life. The stability of these regulatory mechanisms represent the state of good health. The management of this state, constitutes Primary Prevention where both chronic and acute physiopathology defines an alteration in these regulatory mechanisms. We deduce from this reasoning that a tripartite management adapted to the physiological situation is viable and that by choosing parameters specific to individual and collective behavior, it is possible to inject, and combine, at each level and to each demand in order to budget a healthcare system in a more balanced and equitable way. 

  12. The Limits of Exercise Physiology

    DEFF Research Database (Denmark)

    Gabriel, Brendan M; Zierath, Juleen R

    2017-01-01

    Many of the established positive health benefits of exercise have been documented by historical discoveries in the field of exercise physiology. These investigations often assess limits: the limits of performance, or the limits of exercise-induced health benefits. Indeed, several key findings have...... been informed by studying highly trained athletes, in addition to healthy or unhealthy people. Recent progress has been made in regard to skeletal muscle metabolism and personalized exercise regimes. In this perspective, we review some of the historical milestones of exercise physiology, discuss how...... these inform contemporary knowledge, and speculate on future questions....

  13. Back to the future! Revisiting the physiological cost of negative work as a team-based activity for exercise physiology students.

    Science.gov (United States)

    Kilgas, Matthew A; Elmer, Steven J

    2017-03-01

    We implemented a team-based activity in our exercise physiology teaching laboratory that was inspired from Abbott et al.'s classic 1952 Journal of Physiology paper titled "The physiological cost of negative work." Abbott et al. connected two bicycles via one chain. One person cycled forward (muscle shortening contractions, positive work) while the other resisted the reverse moving pedals (muscle lengthening contractions, negative work), and the cost of work was compared. This study was the first to link human whole body energetics with isolated muscle force-velocity characteristics. The laboratory activity for our students ( n = 35) was designed to reenact Abbott et al.'s experiment, integrate previously learned techniques, and illustrate differences in physiological responses to muscle shortening and lengthening contractions. Students (11-12 students/laboratory section) were split into two teams (positive work vs. negative work). One student from each team volunteered to cycle against the other for ~10 min. The remaining students in each team were tasked with measuring: 1 ) O 2 consumption, 2 ) heart rate, 3 ) blood lactate, and 4 ) perceived exertion. Students discovered that O 2 consumption during negative work was about one-half that of positive work and all other physiological parameters were also substantially lower. Muscle lengthening contractions were discussed and applied to rehabilitation and sport training. The majority of students (>90%) agreed or strongly agreed that they stayed engaged during the activity and it improved their understanding of exercise physiology. All students recommended the activity be performed again. This activity was engaging, emphasized teamwork, yielded clear results, was well received, and preserved the history of classic physiological experiments. Copyright © 2017 the American Physiological Society.

  14. Competitive active video games: Physiological and psychological responses in children and adolescents.

    Science.gov (United States)

    Lisón, Juan F; Cebolla, Ausias; Guixeres, Jaime; Álvarez-Pitti, Julio; Escobar, Patricia; Bruñó, Alejandro; Lurbe, Empar; Alcañiz, Mariano; Baños, Rosa

    2015-10-01

    Recent strategies to reduce sedentary behaviour in children include replacing sedentary screen time for active video games. Active video game studies have focused principally on the metabolic consumption of a single player, with physiological and psychological responses of opponent-based multiplayer games to be further evaluated. To determine whether adding a competitive component to playing active video games impacts physiological and psychological responses in players. Sixty-two healthy Caucasian children and adolescents, nine to 14 years years of age, completed three conditions (8 min each) in random order: treadmill walking, and single and opponent-based Kinect active video games. Affect, arousal, rate of perceived exertion, heart rate and percentage of heart rate reserve were measured for each participant and condition. Kinect conditions revealed significantly higher heart rate, percentage of heart rate reserve, rate of perceived exertion and arousal when compared with treadmill walking (Pvideo games improved children's psychological responses (affect and rate of perceived exertion) compared with single play, providing a solution that may contribute toward improved adherence to physical activity.

  15. No evidence for parasitism-linked changes in immune function or oxidative physiology over the annual cycle of an avian species

    NARCIS (Netherlands)

    Pap, Peter L.; Sesarman, Alina; Vagasi, Csongor I.; Buehler, Deborah M.; Patras, Laura; Versteegh, Maaike A.; Banciu, Manuela

    2014-01-01

    Temporally changing environmental conditions occur in most parts of the world and can exert strong pressure on the immune defense of organisms. Seasonality may result in changes in physiological traits over the year, and such changes may be essential for the optimization of defense against

  16. THE ROLE OF ECHOCARDIOGRAPHY IN THE DIFFERENTIAL DIAGNOSIS BETWEEN TRAINING INDUCED MYOCARDIAL HYPERTROPHY VERSUS CARDIOMYOPATHY

    Directory of Open Access Journals (Sweden)

    Tomas Venckunas

    2007-06-01

    Full Text Available Increased myocardial mass due to regular high-volume intense exercise training (so-called athlete's heart is not uncommon. Although directly correlated with the extent of training loads, myocardial hypertrophy is not present exclusively in well-trained or elite athletes. Athlete's heart is considered a physiological phenomenon with no known harmful consequences. However, extreme forms of myocardial hypertrophy due to endurance training resemble a structural heart disease such as hypertrophic cardiomyopathy, a condition associated with substantially increased risk of cardiac event. Endurance sports such as rowing and road cycling, rather than strength/power training, are most commonly associated with left ventricular (LV wall thickness compatible with hypertrophic cardiomyopathy. The differentiation between physiological and maladaptive cardiac hypertrophy in athletes is undoubtedly important, since untreated cardiac abnormality often possesses a real threat of premature death due to heart failure during intense physical exertion. Luckily, the distinction from pathological hypertrophy is usually straightforward using transthoracic echocardiography, as endurance athletes, in addition to moderately and proportionally thickened LV walls with normal acoustic density, tend to possess increased LV diameter. In more uncertain cases, a detailed evaluation of myocardial function using (tissue Doppler and contrast echocardiography is effective. When a doubt still remains, knowledge of an athlete's working capacity may be useful in evaluating whether the insidious cardiac pathology is absent. In such cases cardiopulmonary exercise testing typically resolves the dilemma: indices of aerobic capacity are markedly higher in healthy endurance athletes compared to patients. Other characteristics such as a decrease of LV mass due to training cessation are also discussed in the article

  17. Nigerian Journal of Physiological Sciences: Editorial Policies

    African Journals Online (AJOL)

    Focus and Scope. Nigerian Journal of Physiological Sciences (Niger. J. Physiol. Sci.) is a biannual publication of the Physiological Society of Nigeria. It covers diverse areas of research in physiological sciences, publishing reviews in current research areas and original laboratory and clinical research in physiological ...

  18. Differential equation analysis in biomedical science and engineering partial differential equation applications with R

    CERN Document Server

    Schiesser, William E

    2014-01-01

    Features a solid foundation of mathematical and computational tools to formulate and solve real-world PDE problems across various fields With a step-by-step approach to solving partial differential equations (PDEs), Differential Equation Analysis in Biomedical Science and Engineering: Partial Differential Equation Applications with R successfully applies computational techniques for solving real-world PDE problems that are found in a variety of fields, including chemistry, physics, biology, and physiology. The book provides readers with the necessary knowledge to reproduce and extend the com

  19. Differential equation analysis in biomedical science and engineering ordinary differential equation applications with R

    CERN Document Server

    Schiesser, William E

    2014-01-01

    Features a solid foundation of mathematical and computational tools to formulate and solve real-world ODE problems across various fields With a step-by-step approach to solving ordinary differential equations (ODEs), Differential Equation Analysis in Biomedical Science and Engineering: Ordinary Differential Equation Applications with R successfully applies computational techniques for solving real-worldODE problems that are found in a variety of fields, including chemistry, physics, biology,and physiology. The book provides readers with the necessary knowledge to reproduce andextend the comp

  20. Electronic Textbook in Human Physiology.

    Science.gov (United States)

    Broering, Naomi C.; Lilienfield, Lawrence S.

    1994-01-01

    Describes the development of an electronic textbook in human physiology at the Georgetown University Medical Center Library that was designed to enhance learning and visualization through a prototype knowledge base of core instructional materials stored in digital format on Macintosh computers. The use of computers in the medical curriculum is…

  1. Physiological adaptation in desert birds

    NARCIS (Netherlands)

    Williams, JB; Tieleman, BI; Williams, Joseph B.

    We call into question the idea that birds have not evolved unique physiological adaptations to desert environments. The rate at which desert larks metabolize energy is lower than in mesic species within the same family, and this lower rate of living translates into a lower overall energy requirement

  2. Exercise Effects on Sleep Physiology

    Directory of Open Access Journals (Sweden)

    Sunao eUchida

    2012-04-01

    Full Text Available This mini-review focuses on the effects of exercise on sleep. In its early days, sleep research largely focused on central nervous system (CNS physiology using standardized tabulations of several sleep-specific landmark electroencephalogram (EEG waveforms. Though coarse, this method has enabled the observation and inspection of numerous uninterrupted sleep phenomena. Thus, research on the effects of exercise on sleep began, in the 1960’s, with a focus primarily on sleep EEG (CNS sleep changes. Those early studies found only small effects of exercise on sleep. More recent sleep research has explored not only CNS functioning, but somatic physiology as well. As physical exercise mostly affects somatic functions, endocrine and autonomic nervous system (ANS changes that occur during sleep should be affected by daytime exercise. Since endocrinological, metabolic and autonomic changes can be measured during sleep, it should be possible to assess exercise effects on somatic physiology in addition to CNS sleep quality, building from standard polysomnographic (PSG techniques. Incorporating measures of somatic physiology in the quantitative assessment of sleep could further our understanding of sleep's function as an auto-regulatory, global phenomenon.

  3. [Physiologic skin changes in pregnancy].

    Science.gov (United States)

    Zerouali, Aida; Zaraa, Inès; Trojjet, Sondes; El Euch, Dalenda; Azeiez, Mohamed Iadh; Mokni, Mourad; Zouari, Faouzia; Ben Osman, Amel

    2011-01-01

    Pregnancy is a period of hormonal, immunological, metabolic and vascular changes. Some of them are considered to be physiologic, but others are real diseases specific or not of pregnancy. The aim of our study is to present the epidemiological and clinical physiologic dermatological changes of pregnancy. We present a transversal monocentric study. One hundred pregnant women attending the department of dermatology of the La Rabta hospital were enrolled. Systematic detailed cutaneous examination was performed by a dermatologist to look for a physiologic skin changes. The mean age was 29 years [20-46 years]. Pigmentary changes were the most preponderant (93%), dominated by the areolar region pigmentation (77%). The glandular changes were noted in 75% of cases. The vascular modifications were observed in 77% of pregnant women. Of these, gingival hyperemia was the most common (46%). Others cutaneous changes were less frequent (stria distensae 45%, nevi changes 35%, molluscum gravidarum 10%). The physiologic cutaneous changes during pregnancy are numerous. Our study confirms the frequency and the variability of these modifications. The pigmentary changes were the most common finding. Copyright © 2010 Elsevier Masson SAS. All rights reserved.

  4. Physiology Of Prolonged Bed Rest

    Science.gov (United States)

    Greenleaf, John E.

    1991-01-01

    Report describes physiological effects of prolonged bed rest. Rest for periods of 24 hours or longer deconditions body to some extent; healing proceeds simultaneously with deconditioning. Report provides details on shifts in fluid electrolytes and loss of lean body mass, which comprises everything in body besides fat - that is, water, muscle, and bone. Based on published research.

  5. Activated autologous T cells exert an anti-B-cell chronic lymphatic leukemia effect in vitro and in vivo.

    Science.gov (United States)

    Di Ianni, Mauro; Moretti, Lorenzo; Terenzi, Adelmo; Bazzucchi, Federico; Del Papa, Beatrice; Bazzucchi, Moira; Ciurnelli, Raffaella; Lucchesi, Alessandro; Sportoletti, Paolo; Rosati, Emanuela; Marconi, Pier Francesco; Falzetti, Franca; Tabilio, Antonio

    2009-01-01

    The impact of chronic lymphatic leukemia (CLL) tumor burden on the autologous immune system has already been demonstrated. This study attempted to elucidate the molecular mechanisms underlying T-cell immunologic deficiencies in CLL. Freshly isolated CD3(+) T cells from patients with a diagnosis of CLL and healthy donors were analyzed by gene expression profiling. Activated T cells from 20 patients with CLL were tested in vitro for cytotoxicity against mutated and unmutated autologous B cells and DAUDI, K562 and P815 cell lines. To investigate T-cell mediated cytotoxicity in vivo, we co-transplanted OKT3-activated T lymphocytes and autologous B-cell CLL (B-CLL) cells into NOD/SCID mice. Gene expression profiles of peripheral blood T cells from B-CLL patients showed 25 down-regulated, and 31 up-regulated, genes that were mainly involved in cell differentiation, proliferation, survival, apoptosis, cytoskeleton formation, vesicle trafficking and T-cell activation. After culture, the T-cell count remained unchanged, CD8 cells expanded more than CD4 and a cytotoxicity index >30% was present in 5/20 patients. Cytotoxicity against B autologous leukemic cells did not correlate with B-cell mutational status. Only activated T cells exerting cytotoxicity against autologous leukemic B cells prevented CLL in a human-mouse chimera. This study indicates that patients with CLL are affected by a partial immunologic defect that might be somewhat susceptible to repair. This study identifies the molecular pathways underlying T-cell deficiencies in CLL and shows that cytotoxic T-cell functions against autologous B-CLL can be rebuilt at least in part in vitro and in vivo.

  6. 5α-reductases in human physiology: an unfolding story.

    Science.gov (United States)

    Traish, Abdulmaged M

    2012-01-01

    5α-reductases are a family of isozymes expressed in a wide host of tissues including the central nervous system (CNS) and play a pivotal role in male sexual differentiation, development and physiology. A comprehensive literature search from 1970 to 2011 was made through PubMed and the relevant information was summarized. 5α reductases convert testosterone, progesterone, deoxycorticosterone, aldosterone and corticosterone into their respective 5α-dihydro-derivatives, which serve as substrates for 3α-hydroxysteroid dehydrogenase enzymes. The latter transforms these 5α-reduced metabolites into a subclass of neuroactive steroid hormones with distinct physiological functions. The neuroactive steroid hormones modulate a multitude of functions in human physiology encompassing regulation of sexual differentiation, neuroprotection, memory enhancement, anxiety, sleep and stress, among others. In addition, 5α -reductase type 3 is also implicated in the N-glycosylation of proteins via formation of dolichol phosphate. The family of 5α-reductases was targeted for drug development to treat pathophysiological conditions, such as benign prostatic hyperplasia and androgenetic alopecia. While the clinical use of 5α-reductase inhibitors was well established, the scope and the magnitude of the adverse side effects of such drugs, especially on the CNS, is still unrecognized due to lack of knowledge of the various physiological functions of this family of enzymes, especially in the CNS. There is an urgent need to better understand the function of 5α-reductases and the role of neuroactive steroids in human physiology in order to minimize the potential adverse side effects of inhibitors targeting 5α-reductases to treat benign prostatic hyperplasia and androgenic alopecia.

  7. Physiology and Acoustics of Inspiratory Phonation.

    Science.gov (United States)

    Vanhecke, Françoise; Lebacq, Jean; Moerman, Mieke; Manfredi, Claudia; Raes, Godfried-Willem; DeJonckere, Philippe H

    2016-11-01

    Inspiratory phonation (IP) means phonating with inspiratory airflow. Some vocalists remarkably master this technique, to such an extent that it offers new dramatic, aesthetic, and functional possibilities in singing specific contemporary music. The present study aims to a better understanding of the physiological backgrounds of IP. A total of 51 inhaling utterances were compared with 61 exhaling utterances in a professional soprano highly skilled in inhaling singing, by means of high-speed single-line scanning and advanced acoustic analysis. Ranges of intensity and Fo were kept similar. The main differences are: (1) an inversion of the mucosal wave, (2) a smaller closed quotient in IP, (3) a larger opening/closing quotient in IP with the additional difference that in IP, the quotient is larger than 1 (opening slower than closing), whereas it is less than 1 in expiratory mode (opening faster than closing), (4) a larger vocal-fold excursion in IP, (5) higher values of adaptive normalized noise energy in IP, and (6) a steeper slope of harmonic peaks in IP. However, jitter values are similar (within normal range), as well as damping ratios and central formant frequencies. The two voicing modes cannot be differentiated by blind listening. The basic physiological mechanisms are comparable in both voicing modes, although with specific differences. IP is actually to be considered as an "extended vocal technique," a term applied to vocalization in art music, which falls outside of traditional classical singing styles, but with remarkable possibilities in skilled vocalists. Copyright © 2016 The Voice Foundation. Published by Elsevier Inc. All rights reserved.

  8. Concentrated Differential Privacy

    OpenAIRE

    Dwork, Cynthia; Rothblum, Guy N.

    2016-01-01

    We introduce Concentrated Differential Privacy, a relaxation of Differential Privacy enjoying better accuracy than both pure differential privacy and its popular "(epsilon,delta)" relaxation without compromising on cumulative privacy loss over multiple computations.

  9. Genetic silencing of Nox2 and Nox4 reveals differential roles of these NADPH oxidase homologues in the vasopressor and dipsogenic effects of brain angiotensin II.

    Science.gov (United States)

    Peterson, Jeffrey R; Burmeister, Melissa A; Tian, Xin; Zhou, Yi; Guruju, Mallikarjuna R; Stupinski, John A; Sharma, Ram V; Davisson, Robin L

    2009-11-01

    The renin-angiotensin system exerts a tremendous influence over fluid balance and arterial pressure. Angiotensin II (Ang-II), the effector peptide of the renin-angiotensin system, acts in the central nervous system to regulate neurohumoral outflow and thirst. Dysregulation of Ang-II signaling in the central nervous system is implicated in cardiovascular diseases; however, the mechanisms remain poorly understood. Recently we established that NADPH oxidase (Nox)-derived superoxide acting in the forebrain subfornical organ is critical in the physiological responses to central Ang-II. In addition, we have found that Nox2 and Nox4 are the most abundantly expressed Nox homologues within Ang-II-sensitive sites in the forebrain. To dissect out the functional importance and unique roles of these Nox enzymes in the pressor and dipsogenic effects of central Ang-II, we developed adenoviral vectors expressing small interfering RNA to selectively silence Nox2 or Nox4 expression in the subfornical organ. Our results demonstrate that both Nox2 and Nox4 are required for the full vasopressor effects of brain Ang-II but that only Nox2 is coupled to the Ang-II-induced water intake response. These studies establish the importance of both Nox2- and Nox4-containing NADPH oxidases in the actions of Ang-II in the central nervous system and are the first to reveal differential involvement of these Nox enzymes in the various physiological effects of central Ang-II.

  10. Genetic silencing of Nox2 and Nox4 reveals differential roles of these NADPH oxidase homologues in the vasopressor and dipsogenic effects of brain angiotensin-II

    Science.gov (United States)

    Peterson, Jeffrey R.; Burmeister, Melissa A.; Tian, Xin; Zhou, Yi; Guruju, Mallikarjuna R.; Stupinski, John A.; Sharma, Ram V.; Davisson, Robin L.

    2009-01-01

    The renin angiotensin system (RAS) exerts a tremendous influence over fluid balance and arterial pressure. Angiotensin II (Ang-II), the effector peptide of the RAS, acts in the CNS to regulate neurohumoral outflow and thirst. Dysregulation of Ang-II signaling in the CNS is implicated in cardiovascular diseases, however the mechanisms remain poorly understood. Recently we established that NADPH oxidase (Nox)-derived superoxide acting in the forebrain subfornical organ (SFO) is critical in the physiologic responses to central Ang-II. In addition, we have found that Nox2 and Nox4 are the most abundantly expressed Nox homologues within Ang-II-sensitive sites in the forebrain. To dissect out the functional importance and unique roles of these Nox enzymes in the pressor and dipsogenic effects of central Ang-II, we developed adenoviral vectors expressing siRNA to selectively silence Nox2 or Nox4 expression in the SFO. Our results demonstrate that both Nox2 and Nox4 are required for the full vasopressor effects of brain Ang-II, but that only Nox2 is coupled to the Ang-II-induced water intake response. These studies establish the importance of both Nox2- and Nox4-containing NADPH oxidases in the actions of Ang-II in the CNS, and are the first to reveal differential involvement of these Nox enzymes in the various physiologic effects of central Ang-II. PMID:19805637

  11. Methods for Reducing Effort Exertion in a Gearbox Synchronizer During Shifting Process

    Directory of Open Access Journals (Sweden)

    A. V. Krutashov

    2014-01-01

    Full Text Available In gearbox synchronizer design process, the most important parameter to be determined is the effort required to engage a gear within specified time interval (or vice versa – engaging time for the specified effort. Usually, reduction of said effort implies one of the following approaches: choosing a friction cone as large as possible, or using a multi-cone design. However, according to practical experience and investigations of shifting process, engaging effort may not be the decisive factor in shifting quality assessment. One can observe that during shifting the force exertion process often has two stages. The first stage is a result of the synchronization process itself. The existing second stage, effort amount, and instability of force observed at this stage while repeating shifts, require a thorough investigation. Therefore, the subject of the work was the shifting process stages that affect the engaging effort. The paper gives the certain characteristics of shifting process to demonstrate that there is the second stage in force exertion. The paper describes a technique for calculating the force acting on synchronizing sleeve and presents results of such calculations for several types of synchronizers.These results showed that in the case when tooth rims of a synchronizing sleeve and a gearwheel situated against each other in an adverse way, simultaneous sleeve movement and gearwheel rotation exert the second peak of the force comparable with synchronization effort (≈ 53…71%. The remainder of the paper shows the ways to decrease said second force peak. Recommendations for synchronizers design improvement are given as well. The conclusion has been made that technical requirements for modern synchronizer design, apart from the maximum synchronization effort, must provide relative maximum value of the second peak of at most 1/3 of synchronization effort. This will ensure improved perception of the shifting process.

  12. Motorcycle racer with unilateral forearm flexor and extensor chronic exertional compartment syndrome.

    Science.gov (United States)

    Winkes, Michiel B; Teijink, Joep A; Scheltinga, Marc R

    2016-04-14

    We discuss a case of a 26-year-old man, a motorcycle racer, who presented with progressive pain, weakness and swelling of his right forearm and loss of power in his index finger, experienced during motor racing. Chronic exertional compartment syndrome (CECS) of both flexor and extensor compartments of his forearm was diagnosed by dynamic intracompartmental muscle pressure measurements. After fasciotomies, all symptoms were resolved and the patient was able to improve on his preinjury racing skills, without any limitations. A literature review and a surgical 'how-to' for correct release of the extensor and deep flexor compartments of the forearm are provided. 2016 BMJ Publishing Group Ltd.

  13. Massive right atrial myxoma presenting as syncope and exertional dyspnea: case report

    Directory of Open Access Journals (Sweden)

    Bartosch Carla

    2010-06-01

    Full Text Available Abstract Primary heart neoplasms are rare occurring with an estimated incidence of 0.0017-0.19%. Myxoma is the most prevalent primary heart tumor. The right atrium is an unusual localization, occurring only in 15-20% of myxoma cases. We report a rare case of a massive right atrial myxoma causing tricuspid valve obstruction and presenting as syncope and exertional dyspnea. This case illustrates the influence of myxoma's size, position and mobility as well as patient's body posture and respiration to the development of signs and symptoms. Three-dimensional echocardiography proved useful in surgery planning, allowing a better definition of the tumor outline and attachment.

  14. Reliability and Validity of the OMNI-Vibration Exercise Scale of Perceived Exertion

    OpenAIRE

    Marín, Pedro J.; Alejandro Santos-Lozano; Fernanda Santin-Medeiros; Robertson, Robert J.; Nuria Garatachea

    2012-01-01

    This study examined reliability and concurrent validity of the newly developed OMNI-vibration exercise scale (OMNI-VIBRO) to measure Ratings of Perceived Exertion (RPE) during vibration exercise in twenty recreationally active students (12 males and 8 females). The criterion variables were muscle activity of the Vastus Medialis (VM), Vastus Lateralis (VL), Biceps Femoris (BF), and Medial Gastrocnemius (MG) muscles, as well as accelerations (12.5, 20.2, 30.9, 36.3, 60.1, and 88.4 m·s-2). RPE w...

  15. High-Output Heart Failure from a Hepatic Hemangioma With Exertion-Induced Hypoxia.

    Science.gov (United States)

    Smith, Aaron A H; Nelson, Matthew

    2016-01-01

    Patients with hepatic hemangiomas have been known to have high-output heart failure as a result of left-to-right arteriovenous shunting. We report a patient with a hepatic hemangioma that presented with high-output heart failure with hypoxia on exertion. After embolization of the hemangioma, the patient's hypoxia resolved and ejection fraction improved. In the absence of cardiopulmonary pathophysiology, we presume that our patient's hemangioma was causing a right-to-left shunt as opposed to an expected left-to-right shunt. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. The endoplasmic reticulum exerts control over organelle streaming during cell expansion.

    Science.gov (United States)

    Stefano, Giovanni; Renna, Luciana; Brandizzi, Federica

    2014-03-01

    Cytoplasmic streaming is crucial for cell homeostasis and expansion but the precise driving forces are largely unknown. In plants, partial loss of cytoplasmic streaming due to chemical and genetic ablation of myosins supports the existence of yet-unknown motors for organelle movement. Here we tested a role of the endoplasmic reticulum (ER) as propelling force for cytoplasmic streaming during cell expansion. Through quantitative live-cell analyses in wild-type Arabidopsis thaliana cells and mutants with compromised ER structure and streaming, we demonstrate that cytoplasmic streaming undergoes profound changes during cell expansion and that it depends on motor forces co-exerted by the ER and the cytoskeleton.

  17. Hydrogen Sulfide in Physiology and Diseases of the Digestive Tract

    Directory of Open Access Journals (Sweden)

    Sudha B. Singh

    2015-11-01

    Full Text Available Hydrogen sulfide (H2S is a Janus-faced molecule. On one hand, several toxic functions have been attributed to H2S and exposure to high levels of this gas is extremely hazardous to health. On the other hand, H2S delivery based clinical therapies are being developed to combat inflammation, visceral pain, oxidative stress related tissue injury, thrombosis and cancer. Since its discovery, H2S has been found to have pleiotropic effects on physiology and health. H2S is a gasotransmitter that exerts its effect on different systems, such as gastrointestinal, neuronal, cardiovascular, respiratory, renal, and hepatic systems. In the gastrointestinal tract, in addition to H2S production by mammalian cystathionine-β-synthase (CBS, cystathionine-γ-lyase (CSE, H2S is also generated by the metabolic activity of resident gut microbes, mainly by colonic Sulfate-Reducing Bacteria (SRB via a dissimilatory sulfate reduction (DSR pathway. In the gut, H2S regulates functions such as inflammation, ischemia/ reperfusion injury and motility. H2S derived from gut microbes has been found to be associated with gastrointestinal disorders such as ulcerative colitis, Crohn’s disease and irritable bowel syndrome. This underscores the importance of gut microbes and their production of H2S on host physiology and pathophysiology.

  18. Circulating opioids: possible physiological roles in central nervous function.

    Science.gov (United States)

    Henry, J L

    1982-01-01

    Evidence is reviewed regarding the release of endorphins by such diverse conditions as stress, long distance running, acupuncture, sexual activity, suggestion and ritualistic dancing ceremonies. Additional evidence is cited regarding possible physiological roles of endorphins in antinociception, socialization, euphoria, some mental disorders, drive states and vegetative functions. The concentration of this latter type of evidence is on conditions during which endorphins seem to be exerting effects on a number of different systems together (for example, euphoria is almost always accompanied by analgesia), and the possibility is suggested that the activation of a number of functions together may be due to a global activation of opiate receptors throughout the CNS. A possible basis for this global activation arises from results from this laboratory indicating the presence of a blood-borne opioid hormone, secreted by the pituitary or by an endocrine gland under pituitary control, which is capable of passing from the blood into the CNS. This diffuse endorphinergic system, which is complementary to the well-established endorphinergic neuronal systems in the CNS, thus derives its property of global action on opiate receptors by the diffuse means by which the hormone reaches its target sites, i.e., by passing through the blood brain barrier. Thus, while each specific endorphin-mediated function can be activated by the activation of its respective neural pathway, it is proposed that the hormonal endorphinergic mechanism is activated to produce a global response provoked by conditions to which a more generalized response, including physiological and behavioural changes, is most appropriate.

  19. Influence of Ergometer Design on Physiological Responses during Rowing.

    Science.gov (United States)

    Rossi, J; Piponnier, E; Vincent, L; Samozino, P; Messonnier, L

    2015-11-01

    The aim of this study was to compare the physiological responses and rowing efficiency on 2 different rowing ergometers: stationary vs. dynamic ergometers manufactured by Concept2. 11 oarswomen and oarsmen rowed 4 min at 60% and 70% of peak power output on both ergometers (randomized order). Power output, stroke rate, heart rate, oxygen uptake, carbon dioxide production, lactate accumulation and rating of perceived exertion were recorded at each stage on the 2 ergometers. Gross and net efficiencies were computed. Exercise intensity was associated with increases in all parameters. Rowing on dynamic ergometer was associated with higher heart rate, oxygen uptake, carbon dioxide production and stroke rate, concomitantly to lower blood lactate accumulation but also to lower gross and net efficiencies. The present study showed that rowing efficiency and blood lactate accumulation were lower on the Concept2 dynamic ergometer than on its stationary counterpart. If the use of the Concept2 dynamic ergometer may provide some advantages (reduced risk of injuries), its utilization requires a specific evaluation of physiological responses during an incremental exercise for an adapted management of training. © Georg Thieme Verlag KG Stuttgart · New York.

  20. Rating of Perceived Exertion for Quantification of Training and Combat Loads During Combat Sport-Specific Activities: A Short Review.

    Science.gov (United States)

    Slimani, Maamer; Davis, Philip; Franchini, Emerson; Moalla, Wassim

    2017-10-01

    The aim of this short review was to summarize data pertaining to the rating of perceived exertion (RPE) methods (RPE value and session-RPE) during combat sport-specific activities (i.e., competition and training) based on many factors, including contest type (i.e., official vs. simulated vs. training), combat rounds, age of participants and muscle groups, and their correlation with physiological variables (i.e., blood lactate concentration [La] and heart rate [HR]). The current review shows higher RPE in a match of mixed martial arts (MMAs) than Brazilian jiu-jitsu and kickboxing matches and during the competitive period compared with the precompetitive period. This could be explained by the longer duration of bouts, the higher percentage contribution of aerobic metabolism in MMA than other combat sports and contest type differences (simulated vs. official matches). Thus, this review found significant correlations between RPE or session-RPE, [La] and HR. Particularly, there was a stronger correlation between RPE and [La] during official striking (r = 0.81) than grappling combat sports matches (r = 0.53). In addition, a variation of correlation (moderate to large) between session-RPE and HR-based methods has been reported (i.e., Edwards' training load [r ranged between 0.58 and 0.95] and Banister training impulse [r ranged between 0.52 and 0.86]). Specifically, stronger correlation was apparent in combat sport competition that required a much higher percentage contribution of aerobic metabolism (e.g., karate) and in adult athletes than anaerobic-based combat sports (e.g., taekwondo) and young athletes, respectively. Indeed, the current review highlights that the correlations between session-RPE and HR-based methods were higher during official competition than training sessions. Session-RPE was affected by participants' competitive level, the intensity of session (high vs. low), the training modalities (tactical-technical vs. technical-development vs. simulated

  1. Ezrin/radixin/moesin proteins differentially regulate endothelial hyperpermeability after thrombin

    Science.gov (United States)

    Dudek, Steven M.; Moldobaeva, Nurgul; Kim, Kyung-mi; Ma, Shwu-Fan; Kasa, Anita; Garcia, Joe G. N.; Verin, Alexander D.

    2013-01-01

    Endothelial cell (EC) barrier disruption induced by inflammatory agonists such as thrombin leads to potentially lethal physiological dysfunction such as alveolar flooding, hypoxemia, and pulmonary edema. Thrombin stimulates paracellular gap and F-actin stress fiber formation, triggers actomyosin contraction, and alters EC permeability through multiple mechanisms that include protein kinase C (PKC) activation. We previously have shown that the ezrin, radixin, and moesin (ERM) actin-binding proteins differentially participate in sphingosine-1 phosphate-induced EC barrier enhancement. Phosphorylation of a conserved threonine residue in the COOH-terminus of ERM proteins causes conformational changes in ERM to unmask binding sites and is considered a hallmark of ERM activation. In the present study we test the hypothesis that ERM proteins are phosphorylated on this critical threonine residue by thrombin-induced signaling events and explore the role of the ERM family in modulating thrombin-induced cytoskeletal rearrangement and EC barrier function. Thrombin promotes ERM phosphorylation at this threonine residue (ezrin Thr567, radixin Thr564, moesin Thr558) in a PKC-dependent fashion and induces translocation of phosphorylated ERM to the EC periphery. Thrombin-induced ERM threonine phosphorylation is likely synergistically mediated by protease-activated receptors PAR1 and PAR2. Using the siRNA approach, depletion of either moesin alone or of all three ERM proteins significantly attenuates thrombin-induced increase in EC barrier permeability (transendothelial electrical resistance), cytoskeletal rearrangements, paracellular gap formation, and accumulation of phospho-myosin light chain. In contrast, radixin depletion exerts opposing effects on these indexes. These data suggest that ERM proteins play important differential roles in the thrombin-induced modulation of EC permeability, with moesin promoting barrier dysfunction and radixin opposing it. PMID:23729486

  2. Comparison Between 30-15 Intermittent Fitness Test and Multistage Field Test on Physiological Responses in Wheelchair Basketball Players

    OpenAIRE

    Weissland, Thierry; Faupin, Arnaud; Borel, Benoit; Leprêtre, Pierre-Marie

    2015-01-01

    The intermittent nature of wheelchair court sports suggests using a similar protocol to assess repeated shuttles and recovery abilities. This study aimed to compare performances, physiological responses and perceived rating exertion obtained from the continuous multistage field test (MFT) and the 30-15 intermittent field test (30-15IFT). Eighteen trained wheelchair basketball players (WBP) (WBP: 32.0 ? 5.7 y, IWBF classification: 2.9 ? 1.1 points) performed both incremental field tests in ran...

  3. Physiologic effects of bowel preparation

    DEFF Research Database (Denmark)

    Holte, Kathrine; Nielsen, Kristine Grubbe; Madsen, Jan Lysgård

    2004-01-01

    PURPOSE: Despite the universal use of bowel preparation before colonoscopy and colorectal surgery, the physiologic effects have not been described in a standardized setting. This study was designed to investigate the physiologic effects of bowel preparation. METHODS: In a prospective study, 12...... healthy volunteers (median age, 63 years) underwent bowel preparation with bisacodyl and sodium phosphate. Fluid and food intake were standardized according to weight, providing adequate calorie and oral fluid intake. Before and after bowel preparation, weight, exercise capacity, orthostatic tolerance......, plasma and extracellular volume, balance function, and biochemical parameters were measured. RESULTS: Bowel preparation led to a significant decrease in exercise capacity (median, 9 percent) and weight (median, 1.2 kg). Plasma osmolality was significantly increased from 287 to 290 mmol kg(-1), as well...

  4. PHYSIOLOGY OF ACID BASE BALANCE

    Directory of Open Access Journals (Sweden)

    Awati

    2014-12-01

    Full Text Available Acid-base, electrolyte, and metabolic disturbances are common in the intensive care unit. Almost all critically ill patients often suffer from compound acid-base and electrolyte disorders. Successful evaluation and management of such patients requires recognition of common patterns (e.g., metabolic acidosis and the ability to dissect one disorder from another. The intensivists needs to identify and correct these condition with the easiest available tools as they are the associated with multiorgan failure. Understanding the elements of normal physiology in these areas is very important so as to diagnose the pathological condition and take adequate measures as early as possible. Arterial blood gas analysis is one such tool for early detection of acid base disorder. Physiology of acid base is complex and here is the attempt to simplify it in our day to day application for the benefit of critically ill patients.

  5. Normal Bone Anatomy and Physiology

    OpenAIRE

    Clarke, Bart

    2008-01-01

    This review describes normal bone anatomy and physiology as an introduction to the subsequent articles in this section that discuss clinical applications of iliac crest bone biopsy. The normal anatomy and functions of the skeleton are reviewed first, followed by a general description of the processes of bone modeling and remodeling. The bone remodeling process regulates the gain and loss of bone mineral density in the adult skeleton and directly influences bone strength. Thorough understandin...

  6. Anatomy and physiology of cisternostomy.

    Science.gov (United States)

    Cherian, Iype; Grasso, Giovanni; Bernardo, Antonio; Munakomi, Sunil

    2016-01-01

    Cisternostomy is defined as opening the basal cisterns to atmospheric pressure. This technique helps to reduce the intracranial pressure in severe head trauma as well as other conditions when the so-called sudden "brain swelling" troubles the surgeon. We elaborated the surgical anatomy of this procedure as well as the proposed physiology of how cisternostomy works. This novel technique may change the current trends in neurosurgery.

  7. Exercise Effects on Sleep Physiology

    OpenAIRE

    Uchida, Sunao; Shioda, Kohei; Morita, Yuko; Kubota, Chie; Ganeko, Masashi; Takeda, Noriko

    2012-01-01

    This mini-review focuses on the effects of exercise on sleep. In its early days, sleep research largely focused on central nervous system (CNS) physiology using standardized tabulations of several sleep-specific landmark electroencephalogram (EEG) waveforms. Though coarse, this method has enabled the observation and inspection of numerous uninterrupted sleep phenomena. The research on the effects of exercise on sleep began, in the 1960s, with a focus primarily on sleep related EEG changes (CN...

  8. Exercise Effects on Sleep Physiology

    OpenAIRE

    Sunao eUchida; Kohei eShioda; Yuko eMorita; Chie eKubota; Masashi eGaneko; Noriko eTakeda; Noriko eTakeda

    2012-01-01

    This mini-review focuses on the effects of exercise on sleep. In its early days, sleep research largely focused on central nervous system (CNS) physiology using standardized tabulations of several sleep-specific landmark electroencephalogram (EEG) waveforms. Though coarse, this method has enabled the observation and inspection of numerous uninterrupted sleep phenomena. Thus, research on the effects of exercise on sleep began, in the 1960’s, with a focus primarily on sleep EEG (CNS sleep) c...

  9. In vitro evaluation of physiologically relevant concentrations of teriflunomide on activation and proliferation of primary rodent microglia.

    Science.gov (United States)

    Wostradowski, Tanja; Prajeeth, Chittappen Kandiyil; Gudi, Viktoria; Kronenberg, Jessica; Witte, Sina; Brieskorn, Marina; Stangel, Martin

    2016-09-22

    Teriflunomide, an inhibitor of dihydroorotate dehydrogenase, is thought to ameliorate multiple sclerosis by reducing activation-induced proliferation of lymphocytes, which is highly dependent on de novo pyrimidine synthesis. Nevertheless, its immunomodulatory effects on resident glial cells in the central nervous system are only poorly understood. In this study, we employed physiologically relevant concentrations of teriflunomide and investigated its effects on survival, proliferation, activation, and function of primary rat microglia in vitro. We demonstrate that teriflunomide had no cytotoxic effect on microglia and had only a minor impact on microglial activation. In a concentration- and time-dependent manner, teriflunomide significantly downregulated surface expression of the co-stimulatory molecule CD86. Furthermore, in the highest concentration applied (5 μM), it slightly increased the expression of interleukin-10 in microglia in response to lipopolysaccharide. Treatment with low concentrations of teriflunomide (0.25-1 μM) did not have any impact on the activation or proliferation of microglia. At 5 μM concentration of teriflunomide, we observed a reduction of approximately 30 % in proliferation of microglia in mixed glial cell cultures. Taken together, our in vitro findings suggest that at higher concentrations, teriflunomide potentially exerts its effects by reducing microglial proliferation and not by modulating the M1-/M2-like cell differentiation of primary rat microglia. Thus, teriflunomide has no major impact on the plasticity of microglia; however, the anti-proliferative and minimal anti-inflammatory effects might be clinically relevant for immune modulation in the treatment of neuroinflammatory CNS diseases such as multiple sclerosis.

  10. Single portal endoscopic treatment for chronic exertional compartment syndrome of the forearm.

    Science.gov (United States)

    Pozzi, Alessandro; Pivato, Giorgio; Kask, Kristo; Susini, Francesca; Pegoli, Loris

    2014-09-01

    Chronic exertional compartment syndrome of the forearm is an unusual disease not commonly found in the daily practice of a hand surgeon. This condition is quite rare in the general population but occurs more frequently among musicians and athletes, with the highest incidence found in professional motorcycle drivers. It is mainly because of a critical augmentation of the extracellular pressure of the forearm compartments. The diagnosis is mainly clinical, based on stress dynamic tests and intracompartmental pressure measurements. Traditionally, the treatment of this disease has revolved around trigger activity suspension. In the case of professional athletes, this solution cannot be considered and thus the standard surgical treatment consists of an open forearm fasciotomy. This procedure usually requires a lengthy operation period and has a long recovery time before patients can resume their regular activity. Different surgical endoscopic solutions with mini-open techniques have been proposed to shorten this time and reduce the incision size. The aim of this study was to present a new technique for endoscopic-assisted fasciotomy of the forearm in chronic exertional compartment syndrome using a single mini-incision. Four surgical procedures were performed in 3 patients. They were all treated at our center for this condition, and in one case the disease was found on both sides.

  11. A static dynamometer measuring simultaneous torques exerted at the upper limb.

    Science.gov (United States)

    Boissy, P; Bourbonnais, D; Gravel, D; Arsenault, A B; Leblanc, M

    1998-09-01

    The majority of available dynamometers are designed to measure force or torque in one specific direction, one joint at a time. For the quantification of motor incoordination in neurological patient populations, these dynamometers provide limited information about the global behavior of the limb under investigation. This report describes the potential use and function of a static dynamometer measuring torques exerted simultaneously at the shoulder (flexion-extension, abduction-adduction, internal-external rotation), elbow (flexion-extension), and forearm (pronation-supination). Orthogonal forces were measured at the arm and wrist using strain gauge transducers interfaced with a laboratory computer. The lever arms were specified to a software program and the joint torques were calculated in real time according to static equilibrium equations. The use of the dynamometer is illustrated by characterizing for one hemiparetic subject, the joints torques recorded at the shoulder, elbow, and forearm during isolated submaximal grip exertions at different force levels on both sides. The torques generated at the shoulder, elbow and forearm during the hand grip tasks on the affected side were significantly higher than those obtained on the nonaffected side and increased with the grip force level. These differences probably reflect the loss of movement selectivity observed following a lesion in the central nervous system. Further studies are currently being undertaken in neurological patient populations to characterize and quantify motor deficits using this dynamometer. As a long term goal, we hope that the method and technologies described here will contribute to the evaluation and rehabilitation of these populations.

  12. Absence of Exertional Hyperthermia in a 17 Year Old with Severe Burns

    Science.gov (United States)

    McEntire, Serina J.; Lee, Jong O.; Herndon, David N.; Suman, Oscar E.

    2014-01-01

    Objective An important safety concern when exercising burned patients is the potential for an excessive increase in core body temperature (hyperthermia = body core temperature > 39°C) during exercise. Methods We examined the thermoregulatory response to exercise in the heat (31°C, relative humidity 40%) in a 17 year old with a 99% total body surface area burn. A 30 minute exercise test was performed at an intensity of 75% of his peak aerobic capacity. Intestinal temperature was assessed via telemetry with an ingestible capsule. Intestinal temperature was measured pre-exercise, during, and post-exercise. Results The patient completed 12 minutes of the 30 minute exercise test. Starting core temperature was 36.98 °C and increased 0.69 °C during exercise. After excercise, intestinal temperature continued to increase, but no hyperthermia was noted. Conclusion It has been reported that burned children can safely exercise at room temperature, however, the response in the heat is unknown. This patient did not develop exertional hyperthermia, which we propose is due to his low fitness level and heat intolerance. However, the potential for hyperthermia would be increased if he were forced to maintain a high relative workload in the heat. We propose that severely burned individuals should be able to safely participate in physical activities. However, the decision to stop exercising should be accepted to avoid development of exertional hyperthermia. PMID:19506510

  13. EXERTIONAL COMPARTMENT SYNDROME: REVIEW OF THE LITERATURE AND PROPOSED REHABILITATION GUIDELINES FOLLOWING SURGICAL RELEASE

    Science.gov (United States)

    2011-01-01

    Background: There is little published information regarding postoperative management of patients with Chronic Exertional Compartment Syndrome (CECS). Reports of recurrence of symptoms following surgical decompression exist, and are not uncommon depending on the specific technique used. Recurrence suggests that more time and effort may need to be spent on implementing strategic post-operative rehabilitation management in order to avoid repeat surgical intervention or prolonged symptoms. Objective: To summarize relevant literature regarding CECS and propose scientifically-based guidelines for rehab following compartment release with the rationale based on tissue healing, muscle loading, and scar tissue formation and consideration of all tissues contained in the involved compartment. Literature review: A literature search was performed in PubMed, SPORTDiscus, CINAHL, PEDRO, and Google Scholar using the phrase: “chronic exertional compartment syndrome.” Results: No specific rehabilitation guidelines following surgical compartment release for lower extremity CECS were found in the literature search performed for this clinical commentary. Discussion: The development of the proposed post-operative guidelines may allow for improved long-term outcomes following anterior compartment release. Summary: Adequate description of long-term follow-up of outcomes following compartment release for CECS is lacking in current literature. The proposed guidelines for rehab following compartment release include consideration of tissue healing, muscle loading, scar tissue formation, and consideration of soft tissues contained in the involved compartment. Utilization of the proposed guidelines may allow for future research to be performed in order to assess outcomes following surgical intervention for CECS. PMID:21713230

  14. Fruit extract of the medicinal plant Crataegus oxyacantha exerts genotoxic and mutagenic effects in cultured cells.

    Science.gov (United States)

    de Quadros, Ana Paula Oliveira; Mazzeo, Dania Elisa Christofoletti; Marin-Morales, Maria Aparecida; Perazzo, Fábio Ferreira; Rosa, Paulo Cesar Pires; Maistro, Edson Luis

    2017-01-01

    Crataegus oxyacantha, a plant of the Rosaceae family also known "English hawthorn, haw, maybush, or whitethorn," has long been used for medicinal purposes such as digestive disorders, hyperlipidemia, dyspnea, inducing diuresis, and preventing kidney stones. However, the predominant use of this plant has been to treat cardiovascular disorders. Due to a lack of studies on the genotoxicity of C. oxyacantha, this investigation was undertaken to determine whether its fruit extract exerts cytotoxic, genotoxic, or clastogenic/aneugenic effects in leukocytes and HepG2 (liver hepatocellular carcinoma) cultured human cells, or mutagenic effects in TA100 and TA98 strains of Salmonella typhimurium bacterium. Genotoxicity analysis showed that the extract produced no marked genotoxic effects at concentrations of 2.5 or 5 µg/ml in either cell type; however, at concentrations of 10 µg/ml or higher significant DNA damage was detected. The micronucleus test also demonstrated that concentrations of 10 µg/ml or higher produced clastogenic/aneugenic responses. In the Ames test, the extract induced mutagenic effects in TA98 strain of S. typhimurium with metabolic activation at all tested concentrations (2.5 to 500 µg/ml). Data indicate that, under certain experimental conditions, the fruit extract of C. oxyacantha exerts genotoxic and clastogenic/aneugenic effects in cultured human cells, and with metabolism mutagenicity occurs in bacteria cells.

  15. The role of aerobic fitness on session rating of perceived exertion in futsal players.

    Science.gov (United States)

    Milanez, Vinícius F; Pedro, Rafael E; Moreira, Alexandre; Boullosa, Daniel A; Salle-Neto, Fuad; Nakamura, Fábio Y

    2011-09-01

    The aim of this study was to verify the influence of aerobic fitness (VO2max) on internal training loads, as measured by the session rating of perceived exertion (session-RPE) method. Nine male professional outfield futsal players were monitored for 4 wk of the in-season period with regards to the weekly accumulated session-RPE, while participating in the same training sessions. Single-session-RPE was obtained from the product of a 10-point RPE scale and the duration of exercise. Maximal oxygen consumption was determined during an incremental treadmill test. The average training load throughout the 4 wk period varied between 2,876 and 5,035 arbitrary units. Technical-tactical sessions were the predominant source of loading. There was a significant correlation between VO2max (59.6 ± 2.5 mL · kg-1 · min-1) and overall training load accumulated over the total period (r = -0.75). The VO2max plays a key role in determining the magnitude of an individual's perceived exertion during futsal training sessions.

  16. H-Ras Exerts Opposing Effects on Type I Interferon Responses Depending on Its Activation Status.

    Science.gov (United States)

    Chen, Guann-An; Lin, Yun-Ru; Chung, Hai-Ting; Hwang, Lih-Hwa

    2017-01-01

    Using shRNA high-throughput screening, we identified H-Ras as a regulator of antiviral activity, whose depletion could enhance Sindbis virus replication. Further analyses indicated that depletion of H-Ras results in a robust increase in vesicular stomatitis virus infection and a decrease in Sendai virus (SeV)-induced retinoic acid-inducible gene-I-like receptor (RLR) signaling. Interestingly, however, ectopic expression of wild-type H-Ras results in a biphasic mode of RLR signaling regulation: while low-level expression of H-Ras enhances SeV-induced RLR signaling, high-level expression of H-Ras significantly inhibits this signaling. The inhibitory effects correlate with the activation status of H-Ras. As a result, oncogenic H-Ras, H-RasV12, strongly inhibits SeV-induced IFN-β promoter activity and type I interferon signaling. Conversely, the positive effects exerted by H-Ras on RLR signaling are independent of its signaling activity, as a constitutively inactive form of H-Ras, H-RasN17, also positively regulates RLR signaling. Mechanistically, we demonstrate that depletion of H-Ras reduces the formation of MAVS-TNF receptor-associated factor 3 signaling complexes. These results reveal that the H-Ras protein plays a role in promoting MAVS signalosome assembly in the mitochondria, whereas oncogenic H-Ras exerts a negative effect on type I IFN responses.

  17. Measuring exertion time, duty cycle and hand activity level for industrial tasks using computer vision.

    Science.gov (United States)

    Akkas, Oguz; Lee, Cheng Hsien; Hu, Yu Hen; Harris Adamson, Carisa; Rempel, David; Radwin, Robert G

    2017-12-01

    Two computer vision algorithms were developed to automatically estimate exertion time, duty cycle (DC) and hand activity level (HAL) from videos of workers performing 50 industrial tasks. The average DC difference between manual frame-by-frame analysis and the computer vision DC was -5.8% for the Decision Tree (DT) algorithm, and 1.4% for the Feature Vector Training (FVT) algorithm. The average HAL difference was 0.5 for the DT algorithm and 0.3 for the FVT algorithm. A sensitivity analysis, conducted to examine the influence that deviations in DC have on HAL, found it remained unaffected when DC error was less than 5%. Thus, a DC error less than 10% will impact HAL less than 0.5 HAL, which is negligible. Automatic computer vision HAL estimates were therefore comparable to manual frame-by-frame estimates. Practitioner Summary: Computer vision was used to automatically estimate exertion time, duty cycle and hand activity level from videos of workers performing industrial tasks.

  18. Activity Exerted by a Testosterone Derivative on Myocardial Injury Using an Ischemia/Reperfusion Model

    Science.gov (United States)

    Lauro, Figueroa-Valverde; Francisco, Díaz-Cedillo; Elodia, García-Cervera; Eduardo, Pool-Gómez; Maria, López-Ramos; Marcela, Rosas-Nexticapa; Lenin, Hau-Heredia; Betty, Sarabia-Alcocer; Monica, Velázquez-Sarabia Betty

    2014-01-01

    Some reports indicate that several steroid derivatives have activity at cardiovascular level; nevertheless, there is scarce information about the activity exerted by the testosterone derivatives on cardiac injury caused by ischemia/reperfusion (I/R). Analyzing these data, in this study, a new testosterone derivative was synthetized with the objective of evaluating its effect on myocardial injury using an ischemia/reperfusion model. In addition, perfusion pressure and coronary resistance were evaluated in isolated rat hearts using the Langendorff technique. Additionally, molecular mechanism involved in the activity exerted by the testosterone derivative on perfusion pressure and coronary resistance was evaluated by measuring left ventricular pressure in the absence or presence of the following compounds: flutamide, prazosin, metoprolol, nifedipine, indomethacin, and PINANE TXA2. The results showed that the testosterone derivative significantly increases (P = 0.05) the perfusion pressure and coronary resistance in isolated heart. Other data indicate that the testosterone derivative increases left ventricular pressure in a dose-dependent manner (0.001–100 nM); however, this phenomenon was significantly inhibited (P = 0.06) by indomethacin and PINANE-TXA2  (P = 0.05) at a dose of 1 nM. In conclusion, these data suggest that testosterone derivative induces changes in the left ventricular pressure levels through thromboxane receptor activation. PMID:24839599

  19. Bifidobacterium strains from resident infant human gastrointestinal microflora exert antimicrobial activity.

    Science.gov (United States)

    Liévin, V; Peiffer, I; Hudault, S; Rochat, F; Brassart, D; Neeser, J R; Servin, A L

    2000-11-01

    The gastrointestinal microflora exerts a barrier effect against enteropathogens. The aim of this study was to examine if bifidobacteria, a major species of the human colonic microflora, participates in the barrier effect by developing antimicrobial activity against enterovirulent bacteria. Antibacterial activity was examined in vitro against a wide range of Gram negative and Gram positive pathogens. Inhibition of Salmonella typhimurium SL1334 cell association and cell invasion was investigated in vitro using Caco-2 cells. Colonisation of the gastrointestinal tract in vivo by bifidobacteria was examined in axenic C3/He/Oujco mice. Antimicrobial activity was examined in vivo in axenic C3/He/Oujco mice infected by the lethal S typhimurium C5 strain. Fourteen human bifidobacterium strains isolated from infant stools were examined for antimicrobial activity. Two strains (CA1 and F9) expressed antagonistic activity against pathogens in vitro, inhibited cell entry, and killed intracellular S typhimurium SL1344 in Caco-2 cells. An antibacterial component(s) produced by CA1 and F9 was found to be a lipophilic molecule(s) with a molecular weight of less than 3500. In the axenic C3/He/Oujco mice, CA1 and F9 strains colonised the intestinal tract and protected mice against S typhimurium C5 lethal infection. Several bifidobacterium strains from resident infant human gastrointestinal microflora exert antimicrobial activity, suggesting that they could participate in the "barrier effect" produced by the indigenous microflora.

  20. Changes in muscle activity and perceived exertion during exercises performed on a swiss ball.

    Science.gov (United States)

    Marshall, Paul; Murphy, Bernadette

    2006-08-01

    The objective of this study was to determine differences in electromyographic (EMG) activity of prime mover and abdominal muscles while performing squats, push ups, and double leg lowering with a swiss ball. Twelve healthy subjects performed the movements. There was no difference between the surface conditions for muscle activity during the squat exercise; however, individuals had lower perceived exertion for the swiss ball squat. Activity of the triceps and abdominals was highest performing push ups on the swiss ball, whereas the activity of rectus abdominus (RA) only increased during double leg lowering on the swiss ball. Perceived exertion was highest for the push up and leg-lowering exercise performed on the swiss ball. Increased RA activity during double leg lowering can be attributed to its role as a hip flexor, whereas the lack of a rotation aspect to the task prevented increased oblique muscle activity. The swiss ball appears to only increase muscle activity during exercises where the unstable surface is the primary base of support.

  1. Validity of the CALER and OMNI-bike ratings of perceived exertion.

    Science.gov (United States)

    Barkley, Jacob E; Roemmich, James N

    2008-04-01

    To test the validity of the Cart and Load Effort Rating (CALER) and OMNI bike RPE scales. Children (16 boys aged 9.5 +/- 0.7 and 16 girls aged 9.4 +/- 0.8) performed a progressive exercise test on a cycle ergometer to exhaustion. Random effects models and correlation analysis were used to determine the association of the undifferentiated perceived exertion from the CALER and OMNI bike scales with heart rate and V O2 for concurrent validity and the association of the CALER scale with the validated OMNI bike scale for construct validity. Tests of proportions were performed to compare the proportion of maximal RPE scale (CALER, OMNI bike) with the proportion of maximal heart rate achieved during the final stage of the exercise test. Concurrent validity of the CALER and OMNI bike scales was established, as increases in scores of both scales were associated with (P bike scale (r = 0.93). The proportion of maximal CALER (75 +/- 20%) and OMNI bike (74 +/- 19%) scales were less (P bike RPE scales was established for a progressively increasing exercise paradigm. However, the proportion of maximal perceived exertion scores from both scales was lower than the proportion of predicted maximal heart rate achieved during the final stage of the exercise test.

  2. Update: Exertional hyponatremia, active component, U.S. Armed Forces, 2001-2016.

    Science.gov (United States)

    2017-03-01

    From 2001 through 2016, there were 1,519 incident diagnoses of exertional hyponatremia among active component service members (incidence rate: 6.9 cases per 100,000 person-years [p-yrs]). The incidence rate in 2016 (6.6 cases per 100,000 p-yrs) represented a decrease of 23.3% from 2015. Compared to their respective counterparts, overall incidence rates of exertional hyponatremia were higher among females, those aged 19 years or younger, and recruit trainees. The overall incidence rate during the surveillance period was highest in the Marine Corps, intermediate in the Army and Air Force, and lowest in the Navy. Overall incidence rates were lowest among black, non-Hispanic service members and highest among white, non-Hispanic and Asian/Pacific Islander service members. Service members (particularly recruit trainees) and their supervisors must be vigilant for early signs of heat-related illnesses and must be knowledgeable of the dangers of excessive water consumption and the prescribed limits for water intake during prolonged physical activity (e.g., field training exercises, personal fitness training, recreational activities) in hot, humid weather.

  3. Physiology of in vitro culture

    Directory of Open Access Journals (Sweden)

    Maria Jesús Cañal

    2001-01-01

    Full Text Available The culture procedures described up to the eighties, did not made any mention to the environmental control of in vitro plant development. However, growth rate, development and many of the physiologic-morphologic features of the in vitro grown plants are influenced by the culture vessel. The increasing knowledge about the environmental control of culture vessels under sterile conditions, is helping to change micorpropagation procedures. The in vitro environment with lower rate ventilation, brings about low flow rates of matter and energy, with minimum variations of temperature, high relative humidity and large daily changes of the concentration of CO2 inside the culture vessel. The type of culture vessel (size, shape, fabric and closing system can influence the evolution of the atmosphere along the time of culture. Although submitted to different stresses factors plant can be grown in vitro, but plants can be faulty in their anatomy, morphology and physiology. As a consequence, these plants shown a phenotype unable to survive to ex vitro conditions. Different strategies can be used to control the atmosphere along the different phases of micropropagation, in heterotrophic, mixotrophic or autotrophic cultures. The election of the best strategy will be based on different factors as species, number of transplantes required, or quality-price relationship. enviromental control, tissue culture, micropropagation Keywords: in vitro enviromental, characteristic physiology,

  4. ELECTROKINETICS AND CELL PHYSIOLOGY I.

    Science.gov (United States)

    Jensen, Roy A.; Haas, Felix L.

    1963-01-01

    Jensen, Roy A. (The University of Texas M. D. Anderson Hospital and Tumor Institute, Houston) and Felix L. Haas. Electrokinetics and cell physiology. I. Experimental basis for electrokinetic cell studies. J. Bacteriol. 86:73–78. 1963.—The stable and regular electrokinetic pattern displayed by Bacillus subtilis cell populations was presented as the basis for precisely controlled experimental procedures. The course of electrokinetic behavior characteristic of a cell population was one which paralleled the overall physiology of the culture. The prospects of capitalizing upon this biological feature of the cell were considered in cases where portions of a cell population were separable with respect to some distinct physiological criterion. Such cell fractions may be associated with a discrete and detectable difference in the net charge residing upon the bacterial cell surface. Within a limited pore-size range, membrane filters lost or retained cells, depending upon the electrostatic interaction between cell and filter disc. Fractionation on membrane filters proved to be adjustable and could be controlled by selecting the proper ionic strength in the culture medium. Procedures of this kind have potential for the development of preparative techniques or, alternatively, as experimental vehicles for kinetic analysis. PMID:14051825

  5. Physiological and pathological cardiac hypertrophy.

    Science.gov (United States)

    Shimizu, Ippei; Minamino, Tohru

    2016-08-01

    The heart must continuously pump blood to supply the body with oxygen and nutrients. To maintain the high energy consumption required by this role, the heart is equipped with multiple complex biological systems that allow adaptation to changes of systemic demand. The processes of growth (hypertrophy), angiogenesis, and metabolic plasticity are critically involved in maintenance of cardiac homeostasis. Cardiac hypertrophy is classified as physiological when it is associated with normal cardiac function or as pathological when associated with cardiac dysfunction. Physiological hypertrophy of the heart occurs in response to normal growth of children or during pregnancy, as well as in athletes. In contrast, pathological hypertrophy is induced by factors such as prolonged and abnormal hemodynamic stress, due to hypertension, myocardial infarction etc. Pathological hypertrophy is associated with fibrosis, capillary rarefaction, increased production of pro-inflammatory cytokines, and cellular dysfunction (impairment of signaling, suppression of autophagy, and abnormal cardiomyocyte/non-cardiomyocyte interactions), as well as undesirable epigenetic changes, with these complex responses leading to maladaptive cardiac remodeling and heart failure. This review describes the key molecules and cellular responses involved in physiological/pathological cardiac hypertrophy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Plant Physiological Aspects of Silicon

    Energy Technology Data Exchange (ETDEWEB)

    Epstein, E.; Fan, T.W-M.; Higashi, R.M.; Silk, W.K.

    2002-07-10

    The element silicon, Si, represents an anomaly in plant physiology (Epstein, 1994, 1999b). Plants contain the element in amounts comparable to those of such macronutrient elements as phosphorus, calcium, magnesium, viz. at tissue concentrations (dry weight basis) of about 0.1-10%, although both lower and higher values may be encountered. In some plants, such as rice and sugarcane, Si may be the mineral element present in largest amount. In much of plant physiological research, however, Si is considered a nonentity. Thus, not a single formulation of the widely used nutrient solutions includes Si. Experimental plants grown in these solutions are therefore abnormally low in their content of the element, being able to obtain only what Si is present as an unavoidable contaminant of the nutrient salts used, and from the experimental environment and their own seeds. The reason for the astonishing discrepancy between the prominence of Si in plants and its neglect in much of the enterprise of plant physiological research is that Si does not qualify as an ''essential'' element. Ever since the introduction of the solution culture method in the middle of the last century (Epstein, 1999a, b) it has been found that higher plants can grow in nutrient solutions in the formulation of which Si is not included. The only exceptions are the Equisitaceae (horsetails or scouring rushes), for which Si is a quantitatively major essential element.

  7. Fibromyalgia is Associated With Altered Skeletal Muscle Characteristics Which May Contribute to Post-Exertional Fatigue in Post-Menopausal Women

    Science.gov (United States)

    Srikuea, Ratchakrit; Symons, T. Brock; Long, Douglas E.; Lee, Jonah D.; Shang, Yu; Chomentowski, Peter J.; Yu, Guoqiang; Crofford, Leslie J.; Peterson, Charlotte A.

    2012-01-01

    Objective To identify muscle physiological properties that may contribute to post-exertional fatigue and malaise in women with fibromyalgia (FM). Methods Healthy postmenopausal women with (n=11) and without (n=11) fibromyalgia, age 51–70 years, participated in this study. Physical characteristics along with self-reported questionnaires were evaluated. Strength loss and tissue oxygenation in response to a fatiguing exercise protocol were used to quantify fatigability and the local muscle hemodynamic profile. Muscle biopsies were obtained to assess between-group differences in baseline muscle properties using histochemical, immunohistochemical and electron microscopic analyses. Results No significant difference in muscle fatigue in response to exercise was apparent between healthy controls and subjects with FM. However, self-reported fatigue and pain were correlated to prolonged loss of strength following 12-min of recovery in subjects with FM. Although there was no difference in percent SDH positive (type I) and SDH negative (type II) fibers or in mean fiber cross-sectional area between groups, subjects with FM showed greater size variability and altered fiber size distribution. Only in healthy controls, fatigue-resistance was strongly correlated with the size of SDH positive fibers and hemoglobin oxygenation. By contrast, subjects with FM with the highest percentage of SDH positive fibers recovered strength most effectively, which was correlated to capillary density. However, overall, capillary density was lower in subjects with FM. Conclusion Peripheral mechanisms i.e. altered muscle fiber size distribution and decreased capillary density may contribute to post-exertional fatigue in subjects with FM. Understanding these defects in fibromyalgic muscle may provide valuable insight for treatment. PMID:23124535

  8. Russia-A New Empire Under Construction. The Russian Policy towards Former Communist Satellites-Mechanisms of Exertion of Influence

    National Research Council Canada - National Science Library

    Nogaj, Mariusz

    2008-01-01

    .... This thesis examines how the Russian foreign policy strategy was developed and used as a tool for exertion of influence over the postcommunist states, particularly Poland, Ukraine, and Georgia...

  9. Osteogenic Differentiation in Healthy and Pathological Conditions

    OpenAIRE

    Maria Teresa Valenti; Luca Dalle Carbonare; Monica Mottes

    2016-01-01

    This review focuses on the osteogenic differentiation of mesenchymal stem cells (MSC), bone formation and turn-over in good and ill skeletal fates. The interacting molecular pathways which control bone remodeling in physiological conditions during a lifelong process are described. Then, alterations of the molecular pathways regulating osteogenesis are addressed. In the aging process, as well as in glucocorticoid-induced osteoporosis, bone loss is caused not only by an unbalanced bone resorpti...

  10. Pneuma-fire interactions in Hippocratic physiology.

    Science.gov (United States)

    Frixione, Eugenio

    2013-10-01

    Hippocratic treatises written in the late fifth and early fourth centuries BCE contain some of the earliest conjectures known concerning the physiological roles of the pneuma, or "breath," that was supposed to be involved in various functions within human and animal bodies. A cross-referenced survey of these texts suggests that the contemporary theories on the subject may have gone far beyond the well-known attribution of epilepsy and other diseases to disorders in the flow of pneuma within the vessels. A pattern of co-dependent interplay between air-pneuma and fire-heat is evident among the different sources, despite disagreements of the authors on general outlook and other matters. The mutual engagement of those two elements, in turn, is found woven into elaborate mechanisms to explain, with a cause-to-effect approach, vital processes such as the regulation of body temperature through respiration, embryonic growth through morphogenetic differentiation, and even plant germination. Viewed in a historical context, these features suggest that Hippocratic speculation about pneuma may be representative of a conceptual bridging step, i.e., a stage intermediate between some seminal precedents of Presocratic thought and the more mature Aristotelian and Hellenistic theories.

  11. Ratings of Perceived Exertion of ACSM Exercise Guidelines in Individuals Varying in Aerobic Fitness

    Science.gov (United States)

    Kaufman, Christopher; Berg, Kris; Noble, John; Thomas, James

    2006-01-01

    The physiological responses of high (HF) and low fit (LF) individuals at given perceived exercise intensities were compared to ranges provided by the American College of Sports Medicine (ACSM). Participants were 7 LF and 8 HF men between the ages of 22 and 26 years. All participants performed a maximum oxygen uptake and lactate threshold test and…

  12. Sustained and Transient Vestibular Systems: A Physiological Basis for Interpreting Vestibular Function

    OpenAIRE

    Curthoys, Ian S.; MacDougall, Hamish G; Vidal, Pierre-Paul; de Waele, Catherine

    2017-01-01

    Otolithic afferents with regular resting discharge respond to gravity or low-frequency linear accelerations, and we term these the static or sustained otolithic system. However, in the otolithic sense organs, there is anatomical differentiation across the maculae and corresponding physiological differentiation. A specialized band of receptors called the striola consists of mainly type I receptors whose hair bundles are weakly tethered to the overlying otolithic membrane. The afferent neurons,...

  13. Archives: Nigerian Journal of Physiological Sciences

    African Journals Online (AJOL)

    Items 1 - 19 of 19 ... Archives: Nigerian Journal of Physiological Sciences. Journal Home > Archives: Nigerian Journal of Physiological Sciences. Log in or Register to get access to full text downloads.

  14. Anatomy and physiology of chronic scrotal pain.

    Science.gov (United States)

    Patel, Abhishek P

    2017-05-01

    This article reviews the anatomy and physiology of the scrotum and its contents as it pertains to chronic scrotal pain. Physiology of chronic pain is reviewed, as well as the pathophysiology involved in the development of chronic pain.

  15. Physiological determinants of human acute hypoxia tolerance.

    Science.gov (United States)

    2013-11-01

    AbstractIntroduction. We investigated possible physiological determinants of variability in hypoxia tolerance in subjects given a 5-minute normobaric exposure to 25,000 ft equivalent. Physiological tolerance to hypoxia was defined as the magnitude of...

  16. Biomechanics and physiology in handrim wheelchair propulsion

    NARCIS (Netherlands)

    van der Woude, L.H.V.; Veeger, H.E.J.; Dallmeijer, A.J.; Janssen, T.W.J.; Rozendaal, L.A.

    2001-01-01

    Manual wheelchair propulsion in daily life and sports is increasingly being studied. Initially, an engineering and physiological perspective was taken. More recently a concomitant biomechanics interest is seen. Themes of biomechanical and physiological studies today are performance enhancing aspects

  17. Physiological Parameters Database for Older Adults

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Physiological Parameters Database for Older Adults is available for download and contains physiological parameters values for healthy older human adults (age 60...

  18. The effects of modified exponential tapering technique on perceived exertion, heart rate, time trial performance, VO2max and power output among highly trained junior cyclists.

    Science.gov (United States)

    Ishak, Asmadi; Hashim, Hairul A; Krasilshchikov, Oleksandr

    2016-09-01

    The present study investigated the effects of a 2-week modified exponential taper on physiological adaptation and time trial performance among junior cyclists. Participants (N.=27) with the mean age of 16.95±0.8 years, height of 165.6±6.1 cm and weight of 54.19±8.1 kg were matched into either modified exponential taper (N.=7), normal exponential taper (N.=7), or control (N.=7) groups using their initial VO2max values. Both experimental groups followed a 12-week progressive endurance training program and subsequently, a 2-week tapering phase. A simulated 20-km time trial performance along with VO2max, power output, heart rate and rating of perceived exertion were measured at baseline, pre and post-taper. One way ANOVA was used to analyze the difference between groups before the start of the intervention while mixed factorial ANOVA was used to analyze the difference between groups across measurement sessions. When homogeneity assumption was violated, the Greenhouse-Geisser Value was used for the corrected values of the degrees of freedom for the within subject factor the analysis. Significant interactions between experimental groups and testing sessions were found in VO2max (F=6.67, df=4, P<0.05), power output (F=5.02, df=4, P<0.05), heart rate (F=10.87, df=2.51, P<0.05) rating of perceived exertion (F=13.04, df=4, P<0.05) and 20KM time trial (F=4.64, df=2.63, P<0.05). Post-hoc analysis revealed that both types of taper exhibited positive effects compared to the non-taper condition in the measured performance markers at post-taper while no different were found between the two taper groups. It was concluded that both taper protocols successfully inducing physiological adaptations among the junior cyclists by reducing the volume and maintaining the intensity of training.

  19. TGF-β and Physiological Root Resorption of Deciduous Teeth

    Directory of Open Access Journals (Sweden)

    Emi Shimazaki

    2016-12-01

    Full Text Available The present study was performed to examine how transforming growth factor β (TGF-β in root-surrounding tissues on deciduous teeth regulates the differentiation induction into odontoclasts during physiological root resorption. We prepared root-surrounding tissues with (R or without (N physiological root resorption scraped off at three regions (R1–R3 or N1–N3 from the cervical area to the apical area of the tooth and measured both TGF-β and the tartrate-resistant acid phosphatase (TRAP activities. The TGF-β activity level was increased in N1–N3, whereas the TRAP activity was increased in R2 and R3. In vitro experiments for the receptor activator of nuclear factor-κB (NF-κB ligand (RANKL-mediated osteoclast differentiation revealed that proteins from N1–N3 and R1–R3 enhanced the TRAP activity in RAW264 cells. A genetic study indicated that the mRNA levels of TGF-β1 in N1 and N2 were significantly increased, and corresponded with levels of osteoprotegerin (OPG. In contrast, the expression level of RANKL was increased in R2 and R3. Our findings suggest that TGF-β is closely related to the regulation of OPG induction and RANKL-mediated odontoclast differentiation depending on the timing of RANKL and OPG mRNA expression in the root-surrounding tissues of deciduous teeth during physiological root resorption.

  20. Impact of Exercise Training on Physiological Measures of Physical Fitness in the Elderly.

    Science.gov (United States)

    Mendonca, Goncalo V; Pezarat-Correia, Pedro; Vaz, João R; Silva, Luís; Almeida, Isabel D; Heffernan, Kevin S

    2016-01-01

    Older persons are the fastest growing segment of the population living in the Western hemisphere. Longevity comes at a price, including a higher rate of morbidity, functional and mental disability and the eventual loss of independence. Physical inactivity further aggravates the decline in physiological function along the aging process. Therefore, the promotion of regular exercise may be seen as one of the main non-pharmacological approaches that should be recommended to older adults. We performed a comprehensive review on the interaction between exercise training and improved physical fitness in the elderly. Specifically, 175 papers describing the overall benefits of exercise training on the cardiovascular, neuromuscular and brain function of older adults were included. The effectiveness of training for improving quality of life at an older age was also reviewed. Exercise training can partially reverse the age-related physiological decline and enhance work capacity in the elderly. Numerous studies have shown that maintaining a minimum quantity and quality of physical exercise decreases the risk of cardiovascular mortality, sarcopenia, prevents the onset of osteopenia and even exerts a prophylactic role against neurodegeneration. The systemic physiologic effects are profound and may be directly linked to a favorable feedforward cycle whereby improved physiologic function begets improved physical function and so on. We conclude that structured training programs should be designed to improve the physiological function in this population. Finally, the benefits of exercise training vary as a function of training volume and this relationship is independent of age and sex.