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Sample records for acute physiological responses

  1. Eccentric Exercise: Physiological Characteristics and Acute Responses.

    PubMed

    Douglas, Jamie; Pearson, Simon; Ross, Angus; McGuigan, Mike

    2017-04-01

    An eccentric contraction involves the active lengthening of muscle under an external load. The molecular and neural mechanisms underpinning eccentric contractions differ from those of concentric and isometric contractions and remain less understood. A number of molecular theories have been put forth to explain the unexplained observations during eccentric contractions that deviate from the predictions of the established theories of muscle contraction. Postulated mechanisms include a strain-induced modulation of actin-myosin interactions at the level of the cross-bridge, the activation of the structural protein titin, and the winding of titin on actin. Accordingly, neural strategies controlling eccentric contractions also differ with a greater, and possibly distinct, cortical activation observed despite an apparently lower activation at the level of the motor unit. The characteristics of eccentric contractions are associated with several acute physiological responses to eccentrically-emphasised exercise. Differences in neuromuscular, metabolic, hormonal and anabolic signalling responses during, and following, an eccentric exercise bout have frequently been observed in comparison to concentric exercise. Subsequently, the high levels of muscular strain with such exercise can induce muscle damage which is rarely observed with other contraction types. The net result of these eccentric contraction characteristics and responses appears to be a novel adaptive signal within the neuromuscular system.

  2. Human Physiological Responses to Acute and Chronic Cold Exposure

    NASA Technical Reports Server (NTRS)

    Stocks, Jodie M.; Taylor, Nigel A. S.; Tipton, Michael J.; Greenleaf, John E.

    2001-01-01

    When inadequately protected humans are exposed to acute cold, excessive body heat is lost to the environment and unless heat production is increased and heat loss attenuated, body temperature will decrease. The primary physiological responses to counter the reduction in body temperature include marked cutaneous vasoconstriction and increased metabolism. These responses, and the hazards associated with such exposure, are mediated by a number of factors which contribute to heat production and loss. These include the severity and duration of the cold stimulus; exercise intensity; the magnitude of the metabolic response; and individual characteristics such as body composition, age, and gender. Chronic exposure to a cold environment, both natural and artificial, results in physiological alterations leading to adaptation. Three quite different, but not necessarily exclusive, patterns of human cold adaptation have been reported: metabolic, hypothermic, and insulative. Cold adaptation has also been associated with an habituation response, in which there is a desensitization, or damping, of the normal response to a cold stress. This review provides a comprehensive analysis of the human physiological and pathological responses to cold exposure. Particular attention is directed to the factors contributing to heat production and heat loss during acute cold stress, and the ability of humans to adapt to cold environments.

  3. Human physiological responses to cold exposure: Acute responses and acclimatization to prolonged exposure.

    PubMed

    Castellani, John W; Young, Andrew J

    2016-04-01

    Cold exposure in humans causes specific acute and chronic physiological responses. This paper will review both the acute and long-term physiological responses and external factors that impact these physiological responses. Acute physiological responses to cold exposure include cutaneous vasoconstriction and shivering thermogenesis which, respectively, decrease heat loss and increase metabolic heat production. Vasoconstriction is elicited through reflex and local cooling. In combination, vasoconstriction and shivering operate to maintain thermal balance when the body is losing heat. Factors (anthropometry, sex, race, fitness, thermoregulatory fatigue) that influence the acute physiological responses to cold exposure are also reviewed. The physiological responses to chronic cold exposure, also known as cold acclimation/acclimatization, are also presented. Three primary patterns of cold acclimatization have been observed, a) habituation, b) metabolic adjustment, and c) insulative adjustment. Habituation is characterized by physiological adjustments in which the response is attenuated compared to an unacclimatized state. Metabolic acclimatization is characterized by an increased thermogenesis, whereas insulative acclimatization is characterized by enhancing the mechanisms that conserve body heat. The pattern of acclimatization is dependent on changes in skin and core temperature and the exposure duration.

  4. Acute physiological responses of squirrel monkeys exposed to hyperdynamic environments

    NASA Technical Reports Server (NTRS)

    Fuller, C. A.

    1984-01-01

    Physiological and behavioral responses to a hyperdynamic environment were examined in four adult male squirrel monkeys. After baseline monitoring at 1 G, monkeys were exposed to one of three conditions: (1) +2 Gz for 60 minutes, (2) +2.9 Gz max for 8 minutes (simulating Space Shuttle launch), or (3) +1.7 Gz max for 19 minutes (simulating Space Shuttle reentry). During all experimental conditions, heart rate rose, and colonic temperature began to decline within the first ten minutes of centrifugation and decreased by as much as 2 C in some instances. Behaviorally, during centrifugation, the monkeys seemed to exhibit drowsiness and fall asleep, an observation not made during the control period. It is concluded that primates are susceptible to acute hyperdynamic field exposure.

  5. Tail docking in pigs: acute physiological and behavioural responses.

    PubMed

    Sutherland, M A; Bryer, P J; Krebs, N; McGlone, J J

    2008-02-01

    Tail docking of piglets is a routine procedure on farms to control tail-biting behaviour; however, docking can cause an acute stress response. The objectives of this research were to determine the stress responses to tail docking in piglets and to compare two methods of tail docking; cautery iron (CAUT) and the more commonly used blunt trauma cutters (BT). At approximately 6 days of age, piglets were tail docked using CAUT (n = 20), BT (n = 20) or sham tail docked with their tails remaining intact (CON; n = 40). Blood samples were taken prior to tail docking and at 30, 60 and 90 min after tail docking to evaluate the effect of tail docking on white blood cell (WBC) measures and cortisol concentrations. The above experiment was repeated to observe behaviour without the periodic blood sampling, so as not to confound the effects of blood sampling on piglet behaviour. Piglet behaviour was recorded in the farrowing crate using 1 min scan-samples via live observations for 60 min prior to and 90 min after tail docking. Total WBC counts were reduced (P > 0.05) among BT and CAUT compared with CON piglets 30 min after tail docking. Cortisol concentrations were higher (P < 0.01) among BT compared with CON and CAUT piglets 60 min after tail docking. Cautery and BT-docked piglets spent more (P < 0.05) time posterior scooting compared with CON piglets between 0 and 15 min, and 31 and 45 min after tail docking. Piglets tail docked using CAUT and BT tended to spend more (P < 0.07) time sitting than CON piglets between 0 and 15 min post tail docking. Elevated blood cortisol can be reduced by the use of the CAUT rather than the BT method of tail docking. Although the tail docking-induced rise in cortisol was prevented by using CAUT, the behavioural response to BT and CAUT docking methods was similar.

  6. Response of a physiological controller for ventricular assist devices during acute patho-physiological events: an in vitro study.

    PubMed

    Petrou, Anastasios; Pergantis, Panagiotis; Ochsner, Gregor; Amacher, Raffael; Krabatsch, Thomas; Falk, Volkmar; Meboldt, Mirko; Daners, Marianne Schmid

    2017-02-09

    The current paper analyzes the performance of a physiological controller for turbodynamic ventricular assist devices (tVADs) during acute patho-physiological events. The numerical model of the human blood circulation implemented on our hybrid mock circulation was extended in order to simulate the Valsalva maneuver (VM) and premature ventricular contractions (PVCs). The performance of an end-diastolic volume (EDV)-based physiological controller for VADs, named preload responsive speed (PRS) controller was evaluated under VM and PVCs. A slow and a fast response of the PRS controller were implemented by using a 3 s moving window, and a beat-to-beat method, respectively, to extract the EDV index. The hemodynamics of a pathological circulation, assisted by a tVAD controlled by the PRS controller were analyzed and compared with a constant speed support case. The results show that the PRS controller prevented suction during the VM with both methods, while with constant speed, this was not the case. On the other hand, the pump flow reduction with the PRS controller led to low aortic pressure, while it remained physiological with the constant speed control. Pump backflow was increased when the moving window was used but it avoided sudden undesirable speed changes, which occurred during PVCs with the beat-to-beat method. In a possible clinical implementation of any physiological controller, the desired performance during frequent clinical acute scenarios should be considered.

  7. Principles of exercise physiology: responses to acute exercise and long-term adaptations to training.

    PubMed

    Rivera-Brown, Anita M; Frontera, Walter R

    2012-11-01

    Physical activity and fitness are associated with a lower prevalence of chronic diseases, such as heart disease, cancer, high blood pressure, and diabetes. This review discusses the body's response to an acute bout of exercise and long-term physiological adaptations to exercise training with an emphasis on endurance exercise. An overview is provided of skeletal muscle actions, muscle fiber types, and the major metabolic pathways involved in energy production. The importance of adequate fluid intake during exercise sessions to prevent impairments induced by dehydration on endurance exercise, muscular power, and strength is discussed. Physiological adaptations that result from regular exercise training such as increases in cardiorespiratory capacity and strength are mentioned. The review emphasizes the cardiovascular and metabolic adaptations that lead to improvements in maximal oxygen capacity.

  8. How to regulate the acute physiological response to "aerobic" high-intensity interval exercise.

    PubMed

    Tschakert, Gerhard; Kroepfl, Julia; Mueller, Alexander; Moser, Othmar; Groeschl, Werner; Hofmann, Peter

    2015-03-01

    The acute physiological processes during "aerobic" high-intensity interval exercise (HIIE) and their regulation are inadequately studied. The main goal of this study was to investigate the acute metabolic and cardiorespiratory response to long and short HIIE compared to continuous exercise (CE) as well as its regulation and predictability. Six healthy well-trained sport students (5 males, 1 female; age: 25.7 ± 3.1 years; height: 1.80 ± 0.04 m; weight: 76.7 ± 6.4 kg; VO2max: 4.33 ± 0.7 l·min(-1)) performed a maximal incremental exercise test (IET) and subsequently three different exercise sessions matched for mean load (Pmean) and exercise duration (28 min): 1) long HIIE with submaximal peak workloads (Ppeak = power output at 95 % of maximum heart rate), peak workload durations (tpeak) of 4 min, and recovery durations (trec) of 3 min, 2) short HIIE with Ppeak according to the maximum power output (Pmax) from IET, tpeak of 20 s, and individually calculated trec (26.7 ± 13.4 s), and 3) CE with a target workload (Ptarget) equating to Pmean of HIIE. In short HIIE, mean lactate (Lamean) (5.22 ± 1.41 mmol·l(-1)), peak La (7.14 ± 2.48 mmol·l(-1)), and peak heart rate (HRpeak) (181.00 ± 6.66 b·min(-1)) were significantly lower compared to long HIIE (Lamean: 9.83 ± 2.78 mmol·l(-1); Lapeak: 12.37 ± 4.17 mmol·l(-1), HRpeak: 187.67 ± 5.72 b·min(-1)). No significant differences in any parameters were found between short HIIE and CE despite considerably higher peak workloads in short HIIE. The acute metabolic and peak cardiorespiratory demand during "aerobic" short HIIE was significantly lower compared to long HIIE and regulable via Pmean. Consequently, short HIIE allows a consciously aimed triggering of specific and desired or required acute physiological responses. Key pointsHigh-intensity interval exercise (HIIE) with short peak workload durations (tpeak) induce a lower acute metabolic and peak cardiorespiratory response compared to intervals with long tpeak

  9. Yeast cell wall supplementation alters the physiological and acute phase responses of crossbred heifers to an endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to determine the effect of feeding yeast cell wall (YCW) products on the physiological and acute phase responses of crossbred newly-received heifers to an endotoxin challenge. Heifers (n = 24; 219 ± 2.4 kg) were separated into treatment groups receiving a Control diet (n = 8), ...

  10. The effect of yeast cell wall supplementation on the physiological and acute phase responses of crossbred heifers to endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A study was conducted to determine the effect of feeding yeast cell wall (YCW) products on the physiological and acute phase responses of crossbred newly-received heifers to endotoxin (lipopolysaccharide; LPS) challenge. Heifers (n=24; 218.9+/-2.4 kg) were obtained from commercial sale barns and tra...

  11. OmniGen-AF supplementation modulated the physiological and acute phase responses of Brahman heifers to an endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the effect of feeding OmniGen-AF (OG; Prince Agri Products) on the physiological and acute phase responses (APR) of newly-weaned heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Brahman heifers (n=24; 183±5 kilograms) from the Texas AgriLife Research Center in Overton...

  12. Dried citrus pulp modulates the physiological and acute phase responses of crossbred heifers to an endotoxin challenge

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study examined the effect of feeding dried citrus pulp (CP) pellets on the physiological and acute phase responses (APR) of newly-received crossbred heifers to an endotoxin (lipopolysaccharide; LPS) challenge. Heifers (n=24; 218.3±2.4 kg) were obtained from commercial sale barns and transported...

  13. Acute Physiological and Thermoregulatory Responses to Extended Interval Training in Endurance Runners: Influence of Athletic Performance and Age

    PubMed Central

    García-Pinillos, Felipe; Soto-Hermoso, Víctor Manuel; Latorre-Román, Pedro Ángel

    2015-01-01

    This study aimed to describe the acute impact of extended interval training (EIT) on physiological and thermoregulatory levels, as well as to determine the influence of athletic performance and age effect on the aforementioned response in endurance runners. Thirty-one experienced recreational male endurance runners voluntarily participated in this study. Subjects performed EIT on an outdoor running track, which consisted of 12 runs of 400 m. The rate of perceived exertion, physiological response through the peak and recovery heart rate, blood lactate, and thermoregulatory response through tympanic temperature, were controlled. A repeated measures analysis revealed significant differences throughout EIT in examined variables. Cluster analysis grouped according to the average performance in 400 m runs led to distinguish between athletes with a higher and lower sports level. Cluster analysis was also performed according to age, obtaining an older group and a younger group. The one-way analysis of variance between groups revealed no significant differences (p≥0.05) in the response to EIT. The results provide a detailed description of physiological and thermoregulatory responses to EIT in experienced endurance runners. This allows a better understanding of the impact of a common training stimulus on the physiological level inducing greater accuracy in the training prescription. Moreover, despite the differences in athletic performance or age, the acute physiological and thermoregulatory responses in endurance runners were similar, as long as EIT was performed at similar relative intensity. PMID:26839621

  14. Acute effects of heat on neuropsychological changes and physiological responses under noise condition.

    PubMed

    Bhattacharya, S K; Tripathi, S R; Pradhan, C K; Kashyap, S K

    1990-09-01

    To examine the effects of heat and noise individually and jointly on certain physiological responses and cognitive and neuromotor based functions, 12 male participants were tested under 6 experimental conditions which resulted by combining 3 levels of heat (25 degrees, 30 degrees and 35 degrees C) and 2 levels of white noise (70 and 100 dB). The experiment was carried out in a controlled climatic chamber following two 6 x 6 latin square designs. The results indicated elevations in heart rate, oxygen uptake and body temperature due to the independent effect of heat or the combined effects of heat and noise. The independent action of noise was found to be depressive on the first two responses. On the neuropsychological effects, the heat adversely affected the speed in card sorting (by design configuration) and digit symbol tests, and also the accuracy and error rate in the reasoning ability test. The noise caused performance improvements in critical flicker frequency (simultaneous) and in error rates in card sorting (by design configuration). The combined effects of heat and noise indicated higher error rates in card sorting (by face value), decreased accuracy in reasoning ability and improvements in performance in accuracy scores and error rates in digit symbol test.

  15. Methyl parathion and fenvalerate toxicity in American kestrels: Acute physiological responses and effects of cold

    USGS Publications Warehouse

    Rattner, B.A.; Franson, J.C.

    1984-01-01

    Physiological and toxicological effects of p.o. methyl parathion (0.375-3.0 mg/kg) or fenvalerate (1000-4000 mg/kg) were examined over a 10-h period in American kestrels (Falco sparverius) maintained in thermoneutral (22?C) and cold (-5?C) environments. Methyl parathion was highly toxic (estimated median lethal dose of 3.08 mg/kg, 95% confidence limits of 2.29 -4.14 mg/kg), producing dose-dependent inhibition of brain and plasma cholinesterase activity, hyperglycemia, and elevated plasma corticosterone concentration. Brain and plasma cholinesterase inhibition in excess of 50% was associated with transient but pronounced hypothermia 2 h after intubation, although the magnitude of this response was yariable. Fenvalerate, at doses far exceeding those encountered in the environment, caused mild intoxication and elevated plasma alanine aminotransferase activity. Cold intensified methyl parathion toxicity, but did not affect that of fenvalerate. Thus, it would appear that organophosphorus insecticides pose far greater hazard than pyrethroids to raptorial birds.

  16. Acute physiological responses to castration-related pain in piglets: the effect of two local anesthetics with or without meloxicam.

    PubMed

    Bonastre, C; Mitjana, O; Tejedor, M T; Calavia, M; Yuste, A G; Úbeda, J L; Falceto, M V

    2016-09-01

    Methods to reduce castration-related pain in piglets are still issues of concern and interest for authorities and producers. Our objectives were to estimate the effectiveness of two protocols of local anesthesia (lidocaine and the combination of lidocaine+bupivacaine) as well as the use of meloxicam as a postoperative analgesic in alleviating castration-related pain, measured by acute physiological responses. Eight groups (15 piglets/group) were included in the study: (1) castration without anesthesia or analgesia, without meloxicam (TRAD WITHOUT), (2) castration without anesthesia or analgesia, but with meloxicam (TRAD WITH), (3) handling without meloxicam (SHAM WITHOUT), (4) handling with meloxicam (SHAM WITH), (5) castration after local anesthesia with lidocaine but without meloxicam (LIDO WITHOUT), (6) castration after local anesthesia with lidocaine and meloxicam (LIDO WITH), (7) castration after local anesthesia with lidocaine+bupivacaine without meloxicam (LIDO+BUPI WITHOUT), (8) castration after local anesthesia with lidocaine+bupivacaine and meloxicam (LIDO+BUPI WITH). Acute physiological responses measured included skin surface temperature and serum glucose and cortisol concentrations. On days 4 and 11 post-castration BW was recorded and average daily gain was calculated over this period. Furthermore, piglet mortality was recorded over the 11-day post-castration period. Administration of local anesthetic or meloxicam did not prevent the decrease in skin surface temperature associated with castration. Lidocaine reduced the increase in glucose concentration associated with castration. For castrated pigs, the joint use of lidocaine and meloxicam caused a significant decrease in cortisol concentration; the combination of intratesticular lidocaine and bupivacaine did not seem to be more effective than lidocaine alone. No effect of treatments on mortality and growth were detected.

  17. Acute Physiological Responses to Short- and Long-Stage High-Intensity Interval Exercise in Cardiac Rehabilitation: A Pilot Study.

    PubMed

    Tschakert, Gerhard; Kroepfl, Julia M; Mueller, Alexander; Harpf, Hanns; Harpf, Leonhard; Traninger, Heimo; Wallner-Liebmann, Sandra; Stojakovic, Tatjana; Scharnagl, Hubert; Meinitzer, Andreas; Pichlhoefer, Patriz; Hofmann, Peter

    2016-03-01

    Despite described benefits of aerobic high-intensity interval exercise (HIIE), the acute responses during different HIIE modes and associated health risks have only been sparsely discovered in heart disease patients. Therefore, the aim of this study was to investigate the acute responses for physiological parameters, cardiovascular and inflammatory biomarkers, and catecholamines yielded by two different aerobic HIIE protocols compared to continuous exercise (CE) in phase III cardiac rehabilitation. Eight cardiac patients (7 with coronary heart disease, 1 with myocarditis; 7 males, 1 female; age: 63.0 ± 9.4 years; height: 1.74 ± 0.05 m; weight: 83.6 ± 8.7 kg), all but one treated with ß-blocking agents, performed a maximal symptom-limited incremental exercise test (IET) and three different exercise tests matched for mean load (Pmean) and total duration: 1) short HIIE with a peak workload duration (tpeak) of 20 s and a peak workload (Ppeak) equal to the maximum power output (Pmax) from IET; 2) long HIIE with a tpeak of 4 min, Ppeak was corresponding to the power output at 85 % of maximal heart rate (HRmax) from IET; 3) CE with a target workload equal to Pmean of both HIIE modes. Acute metabolic and peak cardiorespiratory responses were significantly higher during long HIIE compared to short HIIE and CE (p < 0.05) except HRpeak which tended to be higher in long HIIE than in short HIIE (p = 0.08). Between short HIIE and CE, no significant difference was found for any parameter. Acute responses of cardiovascular and inflammatory biomarkers and catecholamines didn't show any significant difference between tests (p > 0.05). All health-related variables remained in a normal range in any test except NT-proBNP, which was already elevated at baseline. Despite a high Ppeak particularly in short HIIE, both HIIE modes were as safe and as well tolerated as moderate CE in cardiac patients by using our methodological approach. Key pointsHigh-intensity interval exercise (HIIE

  18. Acute Physiological Responses to Short- and Long-Stage High-Intensity Interval Exercise in Cardiac Rehabilitation: A Pilot Study

    PubMed Central

    Tschakert, Gerhard; Kroepfl, Julia M.; Mueller, Alexander; Harpf, Hanns; Harpf, Leonhard; Traninger, Heimo; Wallner-Liebmann, Sandra; Stojakovic, Tatjana; Scharnagl, Hubert; Meinitzer, Andreas; Pichlhoefer, Patriz; Hofmann, Peter

    2016-01-01

    Despite described benefits of aerobic high-intensity interval exercise (HIIE), the acute responses during different HIIE modes and associated health risks have only been sparsely discovered in heart disease patients. Therefore, the aim of this study was to investigate the acute responses for physiological parameters, cardiovascular and inflammatory biomarkers, and catecholamines yielded by two different aerobic HIIE protocols compared to continuous exercise (CE) in phase III cardiac rehabilitation. Eight cardiac patients (7 with coronary heart disease, 1 with myocarditis; 7 males, 1 female; age: 63.0 ± 9.4 years; height: 1.74 ± 0.05 m; weight: 83.6 ± 8.7 kg), all but one treated with ß-blocking agents, performed a maximal symptom-limited incremental exercise test (IET) and three different exercise tests matched for mean load (Pmean) and total duration: 1) short HIIE with a peak workload duration (tpeak) of 20 s and a peak workload (Ppeak) equal to the maximum power output (Pmax) from IET; 2) long HIIE with a tpeak of 4 min, Ppeak was corresponding to the power output at 85 % of maximal heart rate (HRmax) from IET; 3) CE with a target workload equal to Pmean of both HIIE modes. Acute metabolic and peak cardiorespiratory responses were significantly higher during long HIIE compared to short HIIE and CE (p < 0.05) except HRpeak which tended to be higher in long HIIE than in short HIIE (p = 0.08). Between short HIIE and CE, no significant difference was found for any parameter. Acute responses of cardiovascular and inflammatory biomarkers and catecholamines didn’t show any significant difference between tests (p > 0.05). All health-related variables remained in a normal range in any test except NT-proBNP, which was already elevated at baseline. Despite a high Ppeak particularly in short HIIE, both HIIE modes were as safe and as well tolerated as moderate CE in cardiac patients by using our methodological approach. Key points High-intensity interval exercise (HIIE

  19. Study of Physiological Responses to Acute Carbon Monoxide Exposure with a Human Patient Simulator

    ERIC Educational Resources Information Center

    Cesari, Whitney A.; Caruso, Dominique M.; Zyka, Enela L.; Schroff, Stuart T.; Evans, Charles H., Jr.; Hyatt, Jon-Philippe K.

    2006-01-01

    Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design,…

  20. Coping with an Acute Psychosocial Challenge: Behavioral and Physiological Responses in Young Women

    PubMed Central

    Villada, Carolina; Hidalgo, Vanesa; Almela, Mercedes; Mastorci, Francesca; Sgoifo, Andrea; Salvador, Alicia

    2014-01-01

    Despite the relevance of behavior in understanding individual differences in the strategies used to cope with stressors, behavioral responses and their relationships with psychobiological changes have received little attention. In this study on young women, we aimed at analyzing the associations among different components of the stress response and behavioral coping using a laboratory psychosocial stressor. The Ethological Coding System for Interviews, as well as neuroendocrine, autonomic and mood parameters, were used to measure the stress response in 34 young women (17 free-cycling women in their early follicular phase and 17 oral contraceptive users) subjected to the Trier Social Stress Test (TSST) and a control condition in a crossover design. No significant differences in cardiac autonomic, negative mood and anxiety responses to the stressor were observed between the two groups of women. However, women in the follicular phase showed a higher cortisol response and a larger decrease in positive mood during the social stress episode, as well as greater anxiety overall. Interestingly, the amount of displacement behavior exhibited during the speaking task of the TSST was positively related to anxiety levels preceding the test, but negatively related to baseline and stress response values of heart rate. Moreover, the amount of submissive behavior was negatively related to basal cortisol levels. Finally, eye contact and low-aggressiveness behaviors were associated with a worsening in mood. Overall, these findings emphasize the close relationship between coping behavior and psychobiological reactions, as well as the role of individual variations in the strategy of coping with a psychosocial stressor. PMID:25489730

  1. Acute Exposure of College Basketball Players to Moderate Altitude: Selected Physiological Responses.

    ERIC Educational Resources Information Center

    Noble, Bruce J.; Maresh, Carl M.

    1979-01-01

    In general, basketball players with moderately high aerobic power who reside at an altitude of 1,000 m do not display the hypoxic response to an altitude of 2,200 m expected of sea level residents and aerobically trained athletes. (JD)

  2. Comparative studies of hemolymph physiology response and HIF-1 expression in different strains of Litopenaeus vannamei under acute hypoxia.

    PubMed

    Wei, Lin; Li, Yuhu; Qiu, Liguo; Zhou, Hailong; Han, Qian; Diao, Xiaoping

    2016-06-01

    Litopenaeus vannamei has a high commercial value and is the primary cultured shellfish species globally. In this study, we have compared the hemolymph physiological responses between two L. vannamei strains under acute hypoxia. The results showed that hemocyanin concentration (HC) of strain A6410 was significantly higher than strain Zhengda; Total hemocyte counts (THC) decreased significantly in both strains under hypoxic stress (p < 0.05). We also investigated the temporal and spatial variations of hypoxia inducible factors 1 (HIF-1) by qRT-PCR. The results showed that hypoxia for 12 h increased the expression levels of HIF-1α in tissues of muscle and gill from the two strains (p < 0.05). In the hepatopancreas, the expression levels of HIF-1 increased significantly in strain Zhengda and decreased significantly in strain A6410 (p < 0.05). No significant changes of HIF-1 expression were detected in the same tissues between the two strains under hypoxia for 6 h (p > 0.05), but in the gills and hepatopancreas under hypoxia for 12 h (p < 0.05). Additionally, the expression level of HIF-1 was higher in the strain Zhengda than A6410 in the same tissue under hypoxia for 12 h. It was indicated that the hypoxic tolerance of Litopenaeus vannamei was closely correlated with the expression level of HIF-1, and the higher expression level of HIF-1 to hypoxia, the lower tolerance to hypoxia in the early stage of hypoxia. These results can help to better understand the molecular mechanisms of hypoxic tolerance and speed up the selective breeding process of hypoxia tolerance in L. vannamei.

  3. Effect of a Six-Week Preparation Period on Acute Physiological Responses to a Simulated Combat in Young National-Level Taekwondo Athletes

    PubMed Central

    Nikolaidis, Pantelis T.; Chtourou, Hamdi; Torres-Luque, Gema; Tasiopoulos, Ioannis G.; Heller, Jan; Padulo, Johnny

    2015-01-01

    The aim of this study was to examine changes in physical attributes, physiological characteristics and responses that occurred in a simulated combat during a six-week preparatory period in young taekwondo athletes. Seven athletes (age 12.17 ± 1.11 years) were examined before (pre-intervention) and after (post-intervention) a preparatory period for physical fitness and physiological responses to a 2×90 s simulated bout with a 30 s rest period. The heart rate (HR) was monitored during the simulated combat, and handgrip muscle strength (HMS) along with the countermovement jump (CMJ) were recorded before and after the combat. When compared with pre-intervention values, in post-intervention we observed a decrease in body mass, body fat percentage, and the HR at rest and during recovery after a 3 min step test, and an increase in maximal velocity of the cycle ergometer force-velocity test, the CMJ and mean power during the 30 s continuous jumping test (p<0.05). Furthermore, HR responses to a simulated combat were lower in the post-intervention session (p<0.05). CMJ values increased after the bout in both pre and post-intervention, with higher absolute values in the latter case (p<0.05), whereas there was no difference in HMS. Based on these findings, it can be concluded that the acute physiological responses to a simulated taekwondo combat vary during a season, which might be explained by changes in physical fitness. PMID:26557196

  4. Effect of a Six-Week Preparation Period on Acute Physiological Responses to a Simulated Combat in Young National-Level Taekwondo Athletes.

    PubMed

    Nikolaidis, Pantelis T; Chtourou, Hamdi; Torres-Luque, Gema; Tasiopoulos, Ioannis G; Heller, Jan; Padulo, Johnny

    2015-09-29

    The aim of this study was to examine changes in physical attributes, physiological characteristics and responses that occurred in a simulated combat during a six-week preparatory period in young taekwondo athletes. Seven athletes (age 12.17 ± 1.11 years) were examined before (pre-intervention) and after (post-intervention) a preparatory period for physical fitness and physiological responses to a 2×90 s simulated bout with a 30 s rest period. The heart rate (HR) was monitored during the simulated combat, and handgrip muscle strength (HMS) along with the countermovement jump (CMJ) were recorded before and after the combat. When compared with pre-intervention values, in post-intervention we observed a decrease in body mass, body fat percentage, and the HR at rest and during recovery after a 3 min step test, and an increase in maximal velocity of the cycle ergometer force-velocity test, the CMJ and mean power during the 30 s continuous jumping test (p<0.05). Furthermore, HR responses to a simulated combat were lower in the post-intervention session (p<0.05). CMJ values increased after the bout in both pre and post-intervention, with higher absolute values in the latter case (p<0.05), whereas there was no difference in HMS. Based on these findings, it can be concluded that the acute physiological responses to a simulated taekwondo combat vary during a season, which might be explained by changes in physical fitness.

  5. Effects of carbohydrate refeeding on physiological responses and psychological and physical performance following acute weight reduction in collegiate wrestlers.

    PubMed

    Finn, Kevin J; Dolgener, Forrest A; Williams, Richard B

    2004-05-01

    The purpose of this study was to determine the effects of carbohydrate refeeding on intermittent sprint exercise, blood lactate response, and mood following a typical weight-reduction program practiced by college wrestlers. Fifteen collegiate wrestlers from the University of Northern Iowa completed 3 trials of intermittent arm cranking and a mood inventory prior to weigh-ins (baseline), after weigh-ins, and 1 hour postconsumption of either 1.5 g carbohydrate (CHO)/kg body mass carbohydrate beverage (25% solution) or placebo taken within 1 hour after weigh-ins. Blood lactate responses were determined with each trial. Repeated measures analysis of variance indicated no significant interaction between group and trial for total work (p = 0.08), blood lactate (p = 0.29), positive mood (p = 0.49), or negative mood (p = 0.78). Simple effects analysis indicated a significant difference in lactate response between trials (p = 0.002); however, no difference for work (p = 0.75), positive mood (p = 0.13), or negative mood (p = 0.08). The results of this study suggest that intermittent sprint exercise, blood lactate response, and mood were not positively affected by ingestion of CHOs following an acute weight-reduction period.

  6. Effects of dietary nitrate supplementation on symptoms of acute mountain sickness and basic physiological responses in a group of male adolescents during ascent to Mount Everest Base Camp.

    PubMed

    Hennis, Philip J; Mitchell, Kay; Gilbert-Kawai, Edward; Bountziouka, Vassiliki; Wade, Angie; Feelisch, Martin; Grocott, Michael P; Martin, Daniel S

    2016-11-30

    The purpose of this study was to investigate the effects of dietary nitrate supplementation, in the form of beetroot juice, on acute mountain sickness (AMS) symptoms and physiological responses, in a group of young males trekking to Mount Everest Base Camp (EBC). Forty healthy male students (mean age (SD): 16 (1) yrs) trekked to EBC over 11 days. Following an overnight fast, each morning participants completed the Lake Louise AMS questionnaire and underwent a series of physiological tests: resting blood pressure as well as resting and exercising heart rate, respiratory rate, and peripheral oxygen saturation. The exercise test consisted of a standardised 2-min stepping protocol and measurements were taken in the last 10 s. Participants in the intervention arm of the study consumed 140 ml of concentrated beetroot juice daily, containing approximately 10 mmol of nitrate, while those in the control arm consumed 140 ml of concentrated blackcurrant cordial with negligible nitrate content. Drinks were taken for the first seven days at high altitude (days 2-8), in two equal doses; one with breakfast, and one with the evening meal. Mixed modelling revealed no significant between-groups difference in the incidence of AMS (Odds Ratio - nitrate vs.

  7. Heat acclimation attenuates physiological strain and the HSP72, but not HSP90α, mRNA response to acute normobaric hypoxia.

    PubMed

    Gibson, Oliver R; Turner, Gareth; Tuttle, James A; Taylor, Lee; Watt, Peter W; Maxwell, Neil S

    2015-10-15

    Heat acclimation (HA) attenuates physiological strain in hot conditions via phenotypic and cellular adaptation. The aim of this study was to determine whether HA reduced physiological strain, and heat shock protein (HSP) 72 and HSP90α mRNA responses in acute normobaric hypoxia. Sixteen male participants completed ten 90-min sessions of isothermic HA (40°C/40% relative humidity) or exercise training [control (CON); 20°C/40% relative humidity]. HA or CON were preceded (HYP1) and proceeded (HYP2) by a 30-min normobaric hypoxic exposure [inspired O2 fraction = 0.12; 10-min rest, 10-min cycling at 40% peak O2 uptake (V̇O2 peak), 10-min cycling at 65% V̇O2 peak]. HA induced greater rectal temperatures, sweat rate, and heart rates (HR) than CON during the training sessions. HA, but not CON, reduced resting rectal temperatures and resting HR and increased sweat rate and plasma volume. Hemoglobin mass did not change following HA nor CON. HSP72 and HSP90α mRNA increased in response to each HA session, but did not change with CON. HR during HYP2 was lower and O2 saturation higher at 65% V̇O2 peak following HA, but not CON. O2 uptake/HR was greater at rest and 65% V̇O2 peak in HYP2 following HA, but was unchanged after CON. At rest, the respiratory exchange ratio was reduced during HYP2 following HA, but not CON. The increase in HSP72 mRNA during HYP1 did not occur in HYP2 following HA. In CON, HSP72 mRNA expression was unchanged during HYP1 and HYP2. In HA and CON, increases in HSP90α mRNA during HYP1 were maintained in HYP2. HA reduces physiological strain, and the transcription of HSP72, but not HSP90α mRNA in acute normobaric hypoxia.

  8. Physiological Benefits of Being Small in a Changing World: Responses of Coho Salmon (Oncorhynchus kisutch) to an Acute Thermal Challenge and a Simulated Capture Event

    PubMed Central

    Clark, Timothy D.; Donaldson, Michael R.; Pieperhoff, Sebastian; Drenner, S. Matthew; Lotto, Andrew; Cooke, Steven J.; Hinch, Scott G.; Patterson, David A.; Farrell, Anthony P.

    2012-01-01

    Evidence is building to suggest that both chronic and acute warm temperature exposure, as well as other anthropogenic perturbations, may select for small adult fish within a species. To shed light on this phenomenon, we investigated physiological and anatomical attributes associated with size-specific responses to an acute thermal challenge and a fisheries capture simulation (exercise+air exposure) in maturing male coho salmon (Oncorhynchus kisutch). Full-size females were included for a sex-specific comparison. A size-specific response in haematology to an acute thermal challenge (from 7 to 20°C at 3°C h−1) was apparent only for plasma potassium, whereby full-size males exhibited a significant increase in comparison with smaller males (‘jacks’). Full-size females exhibited an elevated blood stress response in comparison with full-size males. Metabolic recovery following exhaustive exercise at 7°C was size-specific, with jacks regaining resting levels of metabolism at 9.3±0.5 h post-exercise in comparison with 12.3±0.4 h for full-size fish of both sexes. Excess post-exercise oxygen consumption scaled with body mass in male fish with an exponent of b = 1.20±0.08. Jacks appeared to regain osmoregulatory homeostasis faster than full-size males, and they had higher ventilation rates at 1 h post-exercise. Peak metabolic rate during post-exercise recovery scaled with body mass with an exponent of b∼1, suggesting that the slower metabolic recovery in large fish was not due to limitations in diffusive or convective oxygen transport, but that large fish simply accumulated a greater ‘oxygen debt’ that took longer to pay back at the size-independent peak metabolic rate of ∼6 mg min−1 kg−1. Post-exercise recovery of plasma testosterone was faster in jacks compared with full-size males, suggesting less impairment of the maturation trajectory of smaller fish. Supporting previous studies, these findings suggest that environmental change and non

  9. The impact of chronic stress burden of 520-d isolation and confinement on the physiological response to subsequent acute stress challenge.

    PubMed

    Yi, Buqing; Matzel, Sandra; Feuerecker, Matthias; Hörl, Marion; Ladinig, Camilla; Abeln, Vera; Choukèr, Alexander; Schneider, Stefan

    2015-03-15

    Collective evidence indicates that previous exposure to stressful condition might be able to induce changes in brain structure, HPA axis activity and related neurotransmission, and accordingly affect physiological responses to subsequent challenges. During long-term spaceflight, space travelers have to live under the condition of isolation and confinement in the spacecraft for a long period. It is still largely unknown if this kind of chronic stress burden can induce any long-lasting changes. To address this question, following 520-d isolation and confinement simulating a flight to Mars, the participants and a matched control group were exposed to an acute stress challenge called parabolic flight. Brain cortical activity, HPA axis activity, and sympathetic adrenal-medullary system response were monitored by EEG signal, cortisol secretion, and catecholamine production, respectively. We observed enhanced EEG signals, elevated cortisol levels and increased adrenaline productions. A group effect on cortisol output was revealed showing higher cortisol peak levels in the Mars520 group as compared to the control group, suggesting that HPA axis was to a certain extent more activated in the subjects who had chronic stress experience.

  10. Identifying Drug (Cocaine) Intake Events from Acute Physiological Response in the Presence of Free-living Physical Activity.

    PubMed

    Hossain, Syed Monowar; Ali, Amin Ahsan; Rahman, Mahbubur; Ertin, Emre; Epstein, David; Kennedy, Ashley; Preston, Kenzie; Umbricht, Annie; Chen, Yixin; Kumar, Santosh

    2014-01-01

    A variety of health and behavioral states can potentially be inferred from physiological measurements that can now be collected in the natural free-living environment. The major challenge, however, is to develop computational models for automated detection of health events that can work reliably in the natural field environment. In this paper, we develop a physiologically-informed model to automatically detect drug (cocaine) use events in the free-living environment of participants from their electrocardiogram (ECG) measurements. The key to reliably detecting drug use events in the field is to incorporate the knowledge of autonomic nervous system (ANS) behavior in the model development so as to decompose the activation effect of cocaine from the natural recovery behavior of the parasympathetic nervous system (after an episode of physical activity). We collect 89 days of data from 9 active drug users in two residential lab environments and 922 days of data from 42 active drug users in the field environment, for a total of 11,283 hours. We develop a model that tracks the natural recovery by the parasympathetic nervous system and then estimates the dampening caused to the recovery by the activation of the sympathetic nervous system due to cocaine. We develop efficient methods to screen and clean the ECG time series data and extract candidate windows to assess for potential drug use. We then apply our model on the recovery segments from these windows. Our model achieves 100% true positive rate while keeping the false positive rate to 0.87/day over (9+ hours/day of) lab data and to 1.13/day over (11+ hours/day of) field data.

  11. Effects of work-related sleep restriction on acute physiological and psychological stress responses and their interactions: A review among emergency service personnel.

    PubMed

    Wolkow, Alexander; Ferguson, Sally; Aisbett, Brad; Main, Luana

    2015-01-01

    Emergency work can expose personnel to sleep restriction. Inadequate amounts of sleep can negatively affect physiological and psychological stress responses. This review critiqued the emergency service literature (e.g., firefighting, police/law enforcement, defense forces, ambulance/paramedic personnel) that has investigated the effect of sleep restriction on hormonal, inflammatory and psychological responses. Furthermore, it investigated if a psycho-physiological approach can help contextualize the significance of such responses to assist emergency service agencies monitor the health of their personnel. The available literature suggests that sleep restriction across multiple work days can disrupt cytokine and cortisol levels, deteriorate mood and elicit simultaneous physiological and psychological responses. However, research concerning the interaction between such responses is limited and inconclusive. Therefore, it is unknown if a psycho-physiological relationship exists and as a result, it is currently not feasible for agencies to monitor sleep restriction related stress based on psycho- physiological interactions. Sleep restriction does however, appear to be a major stressor contributing to physiological and psychological responses and thus, warrants further investigation.

  12. Physiological Determinants of Human Acute Hypoxia Tolerance

    DTIC Science & Technology

    2013-11-01

    variables. We chose variables that have been historically associated with both anaerobic and aerobic metabolism, as well as with responses to acute onset...carbon monoxide diffusing capacity (transfer factor): recommendations for a standard technique–1995 update. Am J Respir Crit Care Med 152: 2185–2198... Respiration . New Haven, CT: Yale University Press, 1922. Hart MC, Orzalesi MM, Cook CD. Relation between anatomic respiratory dead space and body size and

  13. Chronic Psychosocial Factors and Acute Physiological Responses to Laboratory-Induced Stress in Healthy Populations: A Quantitative Review of 30 Years of Investigations

    ERIC Educational Resources Information Center

    Chida, Yoichi; Hamer, Mark

    2008-01-01

    This meta-analysis included 729 studies from 161 articles investigating how acute stress responsivity (including stress reactivity and recovery of hypothalamic-pituitary-adrenal [HPA] axis, autonomic, and cardiovascular systems) changes with various chronic psychosocial exposures (job stress; general life stress; depression or hopelessness;…

  14. Stress response physiology of thermophiles.

    PubMed

    Ranawat, Preeti; Rawat, Seema

    2017-04-01

    Thermo (or hyperthermo) philic microorganisms are ubiquitous having a wide range of habitats from freshly fallen snow to pasteurized milk to geothermal areas like hot springs. The variations in physicochemical conditions, viz., temperature, pH, nutrient availability and light intensity in the habitats always pose stress conditions for the inhabitants leading to slow growth or cell death. The industrial processes used for harvesting secondary metabolites such as enzymes, toxins and organic acids also create stressed environments for thermophiles. The production of DNA-binding proteins, activation of reactive oxygen species detoxification system, compatible solute accumulation, expression of heat shock proteins and alterations in morphology are a few examples of physiological changes demonstrated by these microscopic lifeforms in stress. These microorganisms exhibit complex genetic and physiological changes to minimize, adapt to and repair damage caused by extreme environmental disturbances. These changes are termed as 'stress responses' which enable them to stabilize their homeostasis. The exploration of important thermophilic factors would pave the way in engineering the microbial strains for various biotechnological applications. This review article presents a picture of physiological responses of thermophiles against various stress conditions as their mechanisms to respond to stress make them model organisms to further explore them for basic and applied biology purposes.

  15. Neuronal Responses to Physiological Stress

    PubMed Central

    Kagias, Konstantinos; Nehammer, Camilla; Pocock, Roger

    2012-01-01

    Physiological stress can be defined as any external or internal condition that challenges the homeostasis of a cell or an organism. It can be divided into three different aspects: environmental stress, intrinsic developmental stress, and aging. Throughout life all living organisms are challenged by changes in the environment. Fluctuations in oxygen levels, temperature, and redox state for example, trigger molecular events that enable an organism to adapt, survive, and reproduce. In addition to external stressors, organisms experience stress associated with morphogenesis and changes in inner chemistry during normal development. For example, conditions such as intrinsic hypoxia and oxidative stress, due to an increase in tissue mass, have to be confronted by developing embryos in order to complete their development. Finally, organisms face the challenge of stochastic accumulation of molecular damage during aging that results in decline and eventual death. Studies have shown that the nervous system plays a pivotal role in responding to stress. Neurons not only receive and process information from the environment but also actively respond to various stresses to promote survival. These responses include changes in the expression of molecules such as transcription factors and microRNAs that regulate stress resistance and adaptation. Moreover, both intrinsic and extrinsic stresses have a tremendous impact on neuronal development and maintenance with implications in many diseases. Here, we review the responses of neurons to various physiological stressors at the molecular and cellular level. PMID:23112806

  16. Reduced Cortisol and Metabolic Responses of Thin Ewes to an Acute Cold Challenge in Mid-Pregnancy: Implications for Animal Physiology and Welfare

    PubMed Central

    Verbeek, Else; Oliver, Mark Hope; Waas, Joseph Rupert; McLeay, Lance Maxwell; Blache, Dominique; Matthews, Lindsay Ross

    2012-01-01

    Background Low food availability leading to reductions in Body Condition Score (BCS; 0 indicates emaciation and 5 obesity) in sheep often coincides with low temperatures associated with the onset of winter in New Zealand. The ability to adapt to reductions in environmental temperature may be impaired in animals with low BCS, in particular during pregnancy when metabolic demand is higher. Here we assess whether BCS affects a pregnant animal's ability to cope with cold challenges. Methods Eighteen pregnant ewes with a BCS of 2.7±0.1 were fed to attain low (LBC: BCS2.3±0.1), medium (MBC: BCS3.2±0.2) or high BCS (HBC: BCS3.6±0.2). Shorn ewes were exposed to a 6-h acute cold challenge in a climate-controlled room (wet and windy conditions, 4.4±0.1°C) in mid-pregnancy. Blood samples were collected during the BCS change phase, acute cold challenge and recovery phase. Results During the BCS change phase, plasma glucose and leptin concentrations declined while free fatty acids (FFA) increased in LBC compared to MBC (P<0.01, P<0.01 and P<0.05, respectively) and HBC ewes (P<0.05, P<0.01 and P<0.01, respectively). During the cold challenge, plasma cortisol concentrations were lower in LBC than MBC (P<0.05) and HBC ewes (P<0.05), and FFA and insulin concentrations were lower in LBC than HBC ewes (P<0.05 and P<0.001, respectively). Leptin concentrations declined in MBC and HBC ewes while remaining unchanged in LBC ewes (P<0.01). Glucose concentrations and internal body temperature (Tcore) increased in all treatments, although peak Tcore tended to be higher in HBC ewes (P<0.1). During the recovery phase, T4 concentrations were lower in LBC ewes (P<0.05). Conclusion Even though all ewes were able to increase Tcore and mobilize glucose, low BCS animals had considerably reduced cortisol and metabolic responses to a cold challenge in mid-pregnancy, suggesting that their ability to adapt to cold challenges through some of the expected pathways was reduced. PMID:22662144

  17. Sex differences in physiological reactivity to acute psychosocial stress in adolescence

    PubMed Central

    Ordaz, Sarah; Luna, Beatriz

    2012-01-01

    Summary Females begin to demonstrate greater negative affective responses to stress than males in adolescence. This may reflect the concurrent emergence of underlying differences in physiological response systems, including corticolimbic circuitries, the hypothalamic—pituitary— adrenal axis (HPAA), and the autonomic nervous system (ANS). This review examines when sex differences in physiological reactivity to acute psychosocial stress emerge and the directionality of these differences over development. Indeed, the literature indicates that sex differences emerge during adolescence and persist into adulthood for all three physiological response systems. However, the directionality of the differences varies by system. The emerging corti-colimbic reactivity literature suggests greater female reactivity, particularly in limbic regions densely innervated by gonadal hormone receptors. In contrast, males generally show higher levels of HPAA and ANS reactivity. We argue that the contrasting directionality of corticolimbic and peripheral physiological responses may reflect specific effects of gonadal hormones on distinct systems and also sex differences in evolved behavioral responses that demand different levels of peripheral physiological activation. Studies that examine both subjective reports of negative affect and physiological responses indicate that beginning in adolescence, females respond to acute stressors with more intense negative affect than males despite their comparatively lower peripheral physiological responses. This dissociation is not clearly explained by sex differences in the strength of the relationship between physiological and subjective responses. We suggest that females' greater subjective responsivity may instead arise from a greater activity in brain regions that translate stress responses to subjective awareness in adolescence. Future research directions include investigations of the role of pubertal hormones in physiological reactivity

  18. Physiological responses induced by pleasant stimuli.

    PubMed

    Watanuki, Shigeki; Kim, Yeon-Kyu

    2005-01-01

    The specific physiological responses induced by pleasant stimuli were investigated in this study. Various physiological responses of the brain (encephaloelectrogram; EEG), autonomic nervous system (ANS), immune system and endocrine system were monitored when pleasant stimuli such as odors, emotional pictures and rakugo, a typical Japanese comical story-telling, were presented to subjects. The results revealed that (i) EEG activities of the left frontal brain region were enhanced by a pleasant odor; (ii) emotional pictures related to primitive element such as nudes and erotic couples elevated vasomotor sympathetic nervous activity; and (iii) an increase in secretory immunoglobulin A (s-IgA) and a decrease in salivary cortisol (s-cortisol) were induced by rakugo-derived linguistic pleasant emotion. Pleasant emotion is complicated state. However, by considering the evolutionary history of human being, it is possible to assess and evaluate pleasant emotion from certain physiological responses by appropriately summating various physiological parameters.

  19. Autonomic Physiological Response Patterns Related to Intelligence

    ERIC Educational Resources Information Center

    Melis, Cor; van Boxtel, Anton

    2007-01-01

    We examined autonomic physiological responses induced by six different cognitive ability tasks, varying in complexity, that were selected on the basis of on Guilford's Structure of Intellect model. In a group of 52 participants, task performance was measured together with nine different autonomic response measures and respiration rate. Weighted…

  20. [Immune response genes products in human physiology].

    PubMed

    Khaitov, R M; Alekseev, L P

    2012-09-01

    Current data on physiological role of human immune response genes' proteomic products (antigens) are discussed. The antigens are specified by a very high level of diversity that mediates a wide specter ofphysiological functions. They actually provide integrity and biological stability of human as species. These data reveal new ideas on many pathological processes as well as drafts new approaches for prophylaxis and treatment.

  1. Physiologic Responses to Treadmill and Water Running.

    ERIC Educational Resources Information Center

    Bishop, Phillip A.; And Others

    1989-01-01

    Presents results of a study of the physiological responses of uninjured runners to running on a treadmill and in water. Water running may lessen an injured athlete's rate of deconditioning, but indications are that the metabolic cost of water running is not significantly greater than that of treadmill running. (SM)

  2. Acute physiology and chronic health evaluation (APACHE II) and Medicare reimbursement

    PubMed Central

    Wagner, Douglas P.; Draper, Elizabeth A.

    1984-01-01

    This article describes the potential for the acute physiology score (APS) of acute physiology and chronic health evaluation (APACHE) II, to be used as a severity adjustment to diagnosis-related groups (DRG's) or other diagnostic classifications. The APS is defined by a relative value scale applied to 12 objective physiologic variables routinely measured on most hospitalized patients shortly after hospital admission. For intensive care patients, APS at admission is strongly related to subsequent resource costs of intensive care for 5,790 consecutive admissions to 13 large hospitals, across and within diagnoses. The APS could also be used to evaluate quality of care, medical technology, and the response to changing financial incentives. PMID:10311080

  3. Physiological responses to daily light exposure

    NASA Astrophysics Data System (ADS)

    Yang, Yefeng; Yu, Yonghua; Yang, Bo; Zhou, Hong; Pan, Jinming

    2016-04-01

    Long daylength artificial light exposure associates with disorders, and a potential physiological mechanism has been proposed. However, previous studies have examined no more than three artificial light treatments and limited metabolic parameters, which have been insufficient to demonstrate mechanical responses. Here, comprehensive physiological response curves were established and the physiological mechanism was strengthened. Chicks were illuminated for 12, 14, 16, 18, 20, or 22 h periods each day. A quadratic relationship between abdominal adipose weight (AAW) and light period suggested that long-term or short-term light exposure could decrease the amount of AAW. Quantitative relationships between physiological parameters and daily light period were also established in this study. The relationships between triglycerides (TG), cholesterol (TC), glucose (GLU), phosphorus (P) levels and daily light period could be described by quadratic regression models. TG levels, AAW, and BW positively correlated with each other, suggesting long-term light exposure significantly increased AAW by increasing TG thus resulting in greater BW. A positive correlation between blood triiodothyronine (T3) levels and BW suggested that daily long-term light exposure increased BW by thyroid hormone secretion. Though the molecular pathway remains unknown, these results suggest a comprehensive physiological mechanism through which light exposure affects growth.

  4. Human physiological responses to wooden indoor environment.

    PubMed

    Zhang, Xi; Lian, Zhiwei; Wu, Yong

    2017-03-02

    Previous studies are mainly focused on non-wooden environments, whereas few are concerned with wooden ones. How wooden indoor environments impact the physiology of the occupants is still unclear. The purpose of this study was to explore the distinct physiological responses to wooden and non-wooden indoor environments, assessed by physiological parameters tests including blood pressure, electrocardiogram measurements, electro-dermal activity, oxyhemoglobin saturation, skin temperature, and near distance vision. Twenty healthy adults participated in this experiment, and their physiological responses were evaluated in a 90minute investigation. The results illustrated that; less tension and fatigue were generated in the wooden rooms than in the non-wooden rooms when the participants did their work. In addition, the study also found that the wooden environments benefit the autonomic nervous system, respiratory system, and visual system. Moreover, wooden rooms play a valuable role in physiological regulation and ease function especially after a consecutive period of work. These results provide an experimental basis to support that wooden environment is beneficial to indoor occupants than the non-wooden indoor environment.

  5. Physiological responses to daily light exposure

    PubMed Central

    Yang, Yefeng; Yu, Yonghua; Yang, Bo; Zhou, Hong; Pan, Jinming

    2016-01-01

    Long daylength artificial light exposure associates with disorders, and a potential physiological mechanism has been proposed. However, previous studies have examined no more than three artificial light treatments and limited metabolic parameters, which have been insufficient to demonstrate mechanical responses. Here, comprehensive physiological response curves were established and the physiological mechanism was strengthened. Chicks were illuminated for 12, 14, 16, 18, 20, or 22 h periods each day. A quadratic relationship between abdominal adipose weight (AAW) and light period suggested that long-term or short-term light exposure could decrease the amount of AAW. Quantitative relationships between physiological parameters and daily light period were also established in this study. The relationships between triglycerides (TG), cholesterol (TC), glucose (GLU), phosphorus (P) levels and daily light period could be described by quadratic regression models. TG levels, AAW, and BW positively correlated with each other, suggesting long-term light exposure significantly increased AAW by increasing TG thus resulting in greater BW. A positive correlation between blood triiodothyronine (T3) levels and BW suggested that daily long-term light exposure increased BW by thyroid hormone secretion. Though the molecular pathway remains unknown, these results suggest a comprehensive physiological mechanism through which light exposure affects growth. PMID:27098210

  6. Mortality Probability Model III and Simplified Acute Physiology Score II

    PubMed Central

    Vasilevskis, Eduard E.; Kuzniewicz, Michael W.; Cason, Brian A.; Lane, Rondall K.; Dean, Mitzi L.; Clay, Ted; Rennie, Deborah J.; Vittinghoff, Eric; Dudley, R. Adams

    2009-01-01

    Background: To develop and compare ICU length-of-stay (LOS) risk-adjustment models using three commonly used mortality or LOS prediction models. Methods: Between 2001 and 2004, we performed a retrospective, observational study of 11,295 ICU patients from 35 hospitals in the California Intensive Care Outcomes Project. We compared the accuracy of the following three LOS models: a recalibrated acute physiology and chronic health evaluation (APACHE) IV-LOS model; and models developed using risk factors in the mortality probability model III at zero hours (MPM0) and the simplified acute physiology score (SAPS) II mortality prediction model. We evaluated models by calculating the following: (1) grouped coefficients of determination; (2) differences between observed and predicted LOS across subgroups; and (3) intraclass correlations of observed/expected LOS ratios between models. Results: The grouped coefficients of determination were APACHE IV with coefficients recalibrated to the LOS values of the study cohort (APACHE IVrecal) [R2 = 0.422], mortality probability model III at zero hours (MPM0 III) [R2 = 0.279], and simplified acute physiology score (SAPS II) [R2 = 0.008]. For each decile of predicted ICU LOS, the mean predicted LOS vs the observed LOS was significantly different (p ≤ 0.05) for three, two, and six deciles using APACHE IVrecal, MPM0 III, and SAPS II, respectively. Plots of the predicted vs the observed LOS ratios of the hospitals revealed a threefold variation in LOS among hospitals with high model correlations. Conclusions: APACHE IV and MPM0 III were more accurate than SAPS II for the prediction of ICU LOS. APACHE IV is the most accurate and best calibrated model. Although it is less accurate, MPM0 III may be a reasonable option if the data collection burden or the treatment effect bias is a consideration. PMID:19363210

  7. Physiological responses associated with cultural attachment.

    PubMed

    Yap, Wei Jie; Christopoulos, George I; Hong, Ying-Yi

    2017-01-18

    Cultural attachment (CA) suggests that cultural symbols can function as attachment figures, in a similar way to prototypical maternal attachment figures. In order to further understand the psychophysiological mechanisms of CA, we examine whether cultural symbols regulate peripheral physiological indicators of arousal in response to symbolic threats. We supraliminally expose participants to neutral or threatening stimuli, followed by the subliminal presentation of CA and control images, while recording their Skin Conductance Responses (SCR). In tandem with previous work, threat increased SCR when the subliminal image was a control. However, the subliminal presence of a cultural symbol reduced this typically high SCR to threat, potentially suggesting that the threat-related arousal was mitigated. Importantly, metrics related to the way an individual is related to the environment, i.e. the need for cognitive closure, affected physiological responses towards threat and cultural images. Overall, the present study sets the basis for potential emotional mechanisms that could explain how cultural symbols can act as extensions of the prototypical attachment figures and confer the sense of security in the face of threat.

  8. Affectivity of Task, Rehearsal Time, and Physiological Response

    ERIC Educational Resources Information Center

    Baker, Walter M.; And Others

    1975-01-01

    The present experiment extended the research on the relation between language and physiology. Among the topics considered was the relation between physiological responses produced by subjects and the number of words they use in an oral presentation. (Author/RK)

  9. Physiological Responses to Thermal Stress and Exercise

    NASA Astrophysics Data System (ADS)

    Iyota, Hiroyuki; Ohya, Akira; Yamagata, Junko; Suzuki, Takashi; Miyagawa, Toshiaki; Kawabata, Takashi

    The simple and noninvasive measuring methods of bioinstrumentation in humans is required for optimization of air conditioning and management of thermal environments, taking into consideration the individual specificity of the human body as well as the stress conditions affecting each. Changes in human blood circulation were induced with environmental factors such as heat, cold, exercise, mental stress, and so on. In this study, the physiological responses of human body to heat stress and exercise were investigated in the initial phase of the developmental research. We measured the body core and skin temperatures, skin blood flow, and pulse wave as the indices of the adaptation of the cardiovascular system. A laser Doppler skin blood flowmetry using an optical-sensor with a small portable data logger was employed for the measurement. These results reveal the heat-stress and exercise-induced circulatory responses, which are under the control of the sympathetic nerve system. Furthermore, it was suggested that the activity of the sympathetic nervous system could be evaluated from the signals of the pulse wave included in the signals derived from skin blood flow by means of heart rate variability assessments and detecting peak heights of velocity-plethysmogram.

  10. Computations of uncertainty mediate acute stress responses in humans.

    PubMed

    de Berker, Archy O; Rutledge, Robb B; Mathys, Christoph; Marshall, Louise; Cross, Gemma F; Dolan, Raymond J; Bestmann, Sven

    2016-03-29

    The effects of stress are frequently studied, yet its proximal causes remain unclear. Here we demonstrate that subjective estimates of uncertainty predict the dynamics of subjective and physiological stress responses. Subjects learned a probabilistic mapping between visual stimuli and electric shocks. Salivary cortisol confirmed that our stressor elicited changes in endocrine activity. Using a hierarchical Bayesian learning model, we quantified the relationship between the different forms of subjective task uncertainty and acute stress responses. Subjective stress, pupil diameter and skin conductance all tracked the evolution of irreducible uncertainty. We observed a coupling between emotional and somatic state, with subjective and physiological tuning to uncertainty tightly correlated. Furthermore, the uncertainty tuning of subjective and physiological stress predicted individual task performance, consistent with an adaptive role for stress in learning under uncertain threat. Our finding that stress responses are tuned to environmental uncertainty provides new insight into their generation and likely adaptive function.

  11. Computations of uncertainty mediate acute stress responses in humans

    PubMed Central

    de Berker, Archy O.; Rutledge, Robb B.; Mathys, Christoph; Marshall, Louise; Cross, Gemma F.; Dolan, Raymond J.; Bestmann, Sven

    2016-01-01

    The effects of stress are frequently studied, yet its proximal causes remain unclear. Here we demonstrate that subjective estimates of uncertainty predict the dynamics of subjective and physiological stress responses. Subjects learned a probabilistic mapping between visual stimuli and electric shocks. Salivary cortisol confirmed that our stressor elicited changes in endocrine activity. Using a hierarchical Bayesian learning model, we quantified the relationship between the different forms of subjective task uncertainty and acute stress responses. Subjective stress, pupil diameter and skin conductance all tracked the evolution of irreducible uncertainty. We observed a coupling between emotional and somatic state, with subjective and physiological tuning to uncertainty tightly correlated. Furthermore, the uncertainty tuning of subjective and physiological stress predicted individual task performance, consistent with an adaptive role for stress in learning under uncertain threat. Our finding that stress responses are tuned to environmental uncertainty provides new insight into their generation and likely adaptive function. PMID:27020312

  12. Physiologically based toxicokinetic modeling of secondary acute myelolytic leukemia.

    PubMed

    Mukhopadhyay, Manas Kumar; Nath, Debjani

    2014-01-01

    Benzene, designated as environmental and occupational carcinogen and hematotoxin, has been associated with secondary leukemia. To develop a toxicokinetic model of AML, benzene can be used as leukemogenic agent. The aim of the present study was to optimize the dose, period and time of cumulative benzene exposure of Swiss Albino mice and to analyze survival rate; alteration in cell cycle regulation and other clinical manifestations in mice exposed to benzene vapour at a dose 300 ppm × 6 h/day × 5 days/week for 2 weeks, i.e., 9000(a)ppm cumulative dose. Analyzing physiological parameters like plasma enzyme profile, complete hematology (Hb %, RBC indices and WBC differentials), hematopoietic cells morphology, expression of cell cycle regulatory proteins, tissue histology and analysis of DNA fragmentation, optimum conditions were established. Down regulation of p53 and p21 and up regulation of CDK2, CDK4, CDK6, cyclin D1 and E in this exposed group were marked as the optimum conditions of cellular deregulation for the development of secondary AML. Elevated level of Plasma AST/ALT with corresponding changes in liver histology showing extended sinusoids within the hepatocytic cell cords in optimally exposed animals also confirmed the toxicokinetic relation of benzene with leukemia. It can be concluded from the above observations that the 9000(a)ppm exposed animals can serve as the induced laboratory model of secondary acute myeloid leukemia.

  13. Molecular and physiological responses to long-term sublethal ammonia exposure in Atlantic salmon (Salmo salar)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to determine the underlying physiological and molecular responses to long-term sublethal ammonia exposure in Atlantic salmon (Salmo salar) parr. Previous studies have pre- dominately focused on mechanisms during acute, short-term exposure. For that purpose Atlantic s...

  14. Physiology responses of Rhesus monkeys to vibration

    NASA Astrophysics Data System (ADS)

    Hajebrahimi, Zahra; Ebrahimi, Mohammad; Alidoust, Leila; Arabian Hosseinabadi, Maedeh

    Vibration is one of the important environmental factors in space vehicles that it can induce severe physiological responses in most of the body systems such as cardiovascular, respiratory, skeletal, endocrine, and etc. This investigation was to assess the effect of different vibration frequencies on heart rate variability (HRV), electrocardiograms (ECG) and respiratory rate in Rhesus monkeys. Methods: two groups of rhesus monkey (n=16 in each group) was selected as control and intervention groups. Monkeys were held in a sitting position within a specific fixture. The animals of this experiment were vibrated on a table which oscillated right and left with sinusoidal motion. Frequency and acceleration for intervention group were between the range of 1 to 2000 Hz and +0.5 to +3 G during 36 weeks (one per week for 15 min), respectively. All of the animals passed the clinical evaluation (echocardiography, sonography, radiography and blood analysis test) before vibration test and were considered healthy and these tests repeated during and at the end of experiments. Results and discussions: Our results showed that heart and respiratory rates increased significantly in response to increased frequency from 1 to 60 Hz (p <0.05) directly with the +G level reaching a maximum (3G) within a seconds compare to controls. There were no significant differences in heart and respiratory rate from 60 t0 2000 Hz among studied groups. All monkeys passed vibration experiment successfully without any arrhythmic symptoms due to electrocardiography analysis. Conclusion: Our results indicate that vibration in low frequency can effect respiratory and cardiovascular function in rhesus monkey. Keywords: Vibration, rhesus monkey, heart rate, respiratory rate

  15. L-Theanine reduces psychological and physiological stress responses.

    PubMed

    Kimura, Kenta; Ozeki, Makoto; Juneja, Lekh Raj; Ohira, Hideki

    2007-01-01

    L-Theanine is an amino acid contained in green tea leaves which is known to block the binding of L-glutamic acid to glutamate receptors in the brain. Because the characteristics of L-Theanine suggest that it may influence psychological and physiological states under stress, the present study examined these possible effects in a laboratory setting using a mental arithmetic task as an acute stressor. Twelve participants underwent four separate trials: one in which they took L-Theanine at the start of an experimental procedure, one in which they took L-Theanine midway, and two control trials in which they either took a placebo or nothing. The experimental sessions were performed by double-blind, and the order of them was counterbalanced. The results showed that L-Theanine intake resulted in a reduction in the heart rate (HR) and salivary immunoglobulin A (s-IgA) responses to an acute stress task relative to the placebo control condition. Moreover, analyses of heart rate variability indicated that the reductions in HR and s-IgA were likely attributable to an attenuation of sympathetic nervous activation. Thus, it was suggested that the oral intake of L-Theanine could cause anti-stress effects via the inhibition of cortical neuron excitation.

  16. Firefighting acutely increases airway responsiveness.

    PubMed

    Sherman, C B; Barnhart, S; Miller, M F; Segal, M R; Aitken, M; Schoene, R; Daniell, W; Rosenstock, L

    1989-07-01

    The acute effects of the products of combustion and pyrolysis on airway responsiveness among firefighters are poorly documented. To study this relationship, spirometry and methacholine challenge testing (MCT) were performed on 18 active Seattle firefighters before and 5 to 24 h after firefighting. Body plethysmography was used to measure changes in specific airway conductance (SGaw), and results of MCT were analyzed using PD35-SGaw, the cumulative dose causing a 35% decrease in SGaw. Subjects who did not react by the end of the protocol were assigned a value of 640 inhalational units, the largest cumulative dose. Fire exposure was defined as the total time (hours) spent without a self-contained breathing apparatus at the firesite and was categorized as mild (less than 1 h, n = 7), moderate (1 to 2 h, n = 5), or severe (greater than 2 h, n = 6). Mean age of the 18 firefighters was 36.7 +/- 6.7 yr (range, 25 to 51), with a mean of 9.1 +/- 7.9 active years in the trade (range, zero to 22). None was known to be asthmatic. After firefighting, FEV1 % predicted (%pred) and FEF25-75 %pred significantly decreased by means of 3.4 +/- 1.1% and 5.6 +/- 2.6%, respectively. The mean decline in PD35-SGaw after firefighting was 184.5 +/- 53.2 units (p = 0.003). This observed decline in PD35-SGaw could not be explained by decrements in prechallenge SGaw, FEV1, or FVC.(ABSTRACT TRUNCATED AT 250 WORDS)

  17. The acute physiological and mood effects of tea and coffee: the role of caffeine level.

    PubMed

    Quinlan, P T; Lane, J; Moore, K L; Aspen, J; Rycroft, J A; O'Brien, D C

    2000-05-01

    The objective of this study was to determine the effect of caffeine level in tea and coffee on acute physiological responses and mood. Randomised full crossover design in subjects after overnight caffeine abstention was studied. In study 1 (n = 17) the caffeine level was manipulated naturalistically by preparing tea and coffee at different strengths (1 or 2 cups equivalent). Caffeine levels were 37.5 and 75 mg in tea, 75 and 150 mg in coffee, with water and no-drink controls. In study 2 (n = 15) caffeine level alone was manipulated (water, decaffeinated tea, plus 0, 25, 50, 100, and 200 mg caffeine). Beverage volume and temperature (55 degrees C) were constant. SBP, DBP, heart rate, skin temperature, skin conductance, and mood were monitored over each 3-h study session. In study 1, tea and coffee produced mild autonomic stimulation and an elevation in mood. There were no effects of tea vs. coffee or caffeine dose, despite a fourfold variation in the latter. Increasing beverage strength was associated with greater increases in DBP and energetic arousal. In study 2, caffeinated beverages increased SBP, DBP, and skin conductance and lowered heart rate and skin temperature compared to water. Significant dose-response relationships to caffeine were seen only for SBP, heart rate, and skin temperature. There were significant effects of caffeine on energetic arousal but no consistent dose-response effects. Caffeinated beverages acutely stimulate the autonomic nervous system and increase alertness. Although caffeine can exert dose-dependent effects on a number of acute autonomic responses, caffeine level is not an important factor. Factors besides caffeine may contribute to these acute effects.

  18. PHYSIOLOGICAL RESPONSES OF MEN DURING SLEEP DEPRIVATION,

    DTIC Science & Technology

    The effects of 84 hours of sleep deprivation were examined in a group of six young men and compared with a group of six controls. Subjects were... sleep deprivation , physiological regulating systems are relatively unaffected by sleep loss. (Author)

  19. Resistance Training: Physiological Responses and Adaptations (Part 3 of 4).

    ERIC Educational Resources Information Center

    Fleck, Steven J.; Kraemer, William J.

    1988-01-01

    The physiological responses and adaptations which occur as a result of resistance training, such as cardiovascular responses, serum lipid count, body composition, and neural adaptations are discussed. Changes in the endocrine system are also described. (JL)

  20. Personality and physiological reactions to acute psychological stress.

    PubMed

    Bibbey, Adam; Carroll, Douglas; Roseboom, Tessa J; Phillips, Anna C; de Rooij, Susanne R

    2013-10-01

    Stable personality traits have long been presumed to have biological substrates, although the evidence relating personality to biological stress reactivity is inconclusive. The present study examined, in a large middle aged cohort (N=352), the relationship between key personality traits and both cortisol and cardiovascular reactions to acute psychological stress. Salivary cortisol and cardiovascular activity were measured at rest and in response to a psychological stress protocol comprising 5min each of a Stroop task, mirror tracing, and a speech task. Participants subsequently completed the Big Five Inventory to assess neuroticism, agreeableness, openness to experience, extraversion, and conscientiousness. Those with higher neuroticism scores exhibited smaller cortisol and cardiovascular stress reactions, whereas participants who were less agreeable and less open had smaller cortisol and cardiac reactions to stress. These associations remained statistically significant following adjustment for a range of potential confounding variables. Thus, a negative personality disposition would appear to be linked to diminished stress reactivity. These findings further support a growing body of evidence which suggests that blunted stress reactivity may be maladaptive.

  1. Rapid changes in cell physiology as a result of acute thermal stress house sparrows, Passer domesticus.

    PubMed

    Jimenez, Ana G; Williams, Joseph B

    2014-12-01

    Given that our climate is rapidly changing, Physiological Ecologists have the critical task of identifying characteristics of species that make them either resilient or susceptible to changes in their natural air temperature regime. Because climate change models suggest that heat events will become more common, and in some places more extreme, it is important to consider how extreme heat events might affect the physiology of a species. The implications of more frequent heat wave events for birds have only recently begun to be addressed, however, the impact of these events on the cellular physiology of a species is difficult to assess. We have developed a novel approach using dermal fibroblasts to explore how short-term thermal stress at the whole animal level might affect cellular rates of metabolism. House sparrows, Passer domesticus were separated into a "control group" and a "heat shocked" group, the latter acclimated to 43°C for 24h. We determined the plasticity of cellular thermal responses by assigning a "recovery group" that was heat shocked as above, but then returned to room temperature for 24h. Primary dermal fibroblasts were grown from skin of all treatment groups and the pectoralis muscle was collected. We found that glycolysis (ECAR) and oxygen consumption rates (OCR), measured using a Seahorse XF 96 analyzer, were significantly higher in the fibroblasts from the heat shocked group of House sparrows compared with their control counterparts. Additionally, muscle fiber diameters decreased and, in turn, Na(+)-K(+)-ATPase maximal activity in the muscle significantly increased in heat shocked sparrows compared with birds in the control group. All of these physiological alterations due to short-term heat exposure were reversible within 24h of recovery at room temperature. These results show that acute exposure to heat stress significantly alters the cellular physiology of sparrows, but that this species is plastic enough to recover from such a thermal

  2. Fibrin(ogen) mediates acute inflammatory responses to biomaterials

    PubMed Central

    1993-01-01

    Although "biocompatible" polymeric elastomers are generally nontoxic, nonimmunogenic, and chemically inert, implants made of these materials may trigger acute and chronic inflammatory responses. Early interactions between implants and inflammatory cells are probably mediated by a layer of host proteins on the material surface. To evaluate the importance of this protein layer, we studied acute inflammatory responses of mice to samples of polyester terephthalate film (PET) that were implanted intraperitoneally for short periods. Material preincubated with albumin is "passivated," accumulating very few adherent neutrophils or macrophages, whereas uncoated or plasma- coated PET attracts large numbers of phagocytes. Neither IgG adsorption nor surface complement activation is necessary for this acute inflammation; phagocyte accumulation on uncoated implants is normal in hypogammaglobulinemic mice and in severely hypocomplementemic mice. Rather, spontaneous adsorption of fibrinogen appears to be critical: (a) PET coated with serum or hypofibrinogenemic plasma attracts as few phagocytes as does albumin-coated material; (b) in contrast, PET preincubated with serum or hypofibrinogenemic plasma containing physiologic amounts of fibrinogen elicits "normal" phagocyte recruitment; (c) most importantly, hypofibrinogenemic mice do not mount an inflammatory response to implanted PET unless the material is coated with fibrinogen or the animals are injected with fibrinogen before implantation. Thus, spontaneous adsorption of fibrinogen appears to initiate the acute inflammatory response to an implanted polymer, suggesting an interesting nexus between two major iatrogenic effects of biomaterials: clotting and inflammation. PMID:8245787

  3. Relationship between cardiorespiratory fitness and physiological responses to films.

    PubMed

    Cantor, J R; Zillmann, D; Day, K D

    1978-06-01

    Subject's physiological responses and rated reactions to a medical film and an erotic film were assessed. Later cardiovascular fitness levels were determined by subject's physiological responses to an exercise task. The greater the increase in the subject's systolic blood pressure after exercise and the slower the recovery, the lower the fitness level. A median split on the fitness scores of males and females separately was used to determine levels of relatively low and high fitness. Subjects in low fitness had significantly greater sympathetic-arousal responses to the two films as measured in systolic blood-pressure increases and skin-temperature decreases. Subjects in the two fitness levels did not differ in ratings of their own physiological or emotional responses to the films. Reported interoception of the magnitude of physiological responses was inaccurate, especially for subjects in low fitness.

  4. Comparison of physiological responses to affect eliciting pictures and music.

    PubMed

    Kim, Jongwan; Wedell, Douglas H

    2016-03-01

    Recent investigations of the neural correlates of affect elicited from different modalities have found both modality-general and modality-specific representations (Chikazoe et al., 2014). The implications for how physiological responses to affect differ across stimulus modalities have not been fully investigated. This study examined similarities and differences between physiological signatures of affect derived from two different modes of presentation: visual pictures and auditory music sampled from an affective space defined by valence and arousal. Electromyography recordings for the zygomaticus major (EMGZ) and corrugator supercilii (EMGC) were measured along with heart rate and skin conductance level (SCL). Multidimensional scaling was used to visualize relationships from physiological and behavioral responses, and the observed relationships were statistically evaluated using multivariate and univariate analyses. Results for physiological measures demonstrated that valence was represented in the same general way across modalities, primarily reflected in EMGC responses. Arousal, however, was represented in a modality-specific manner, with SCL and EMGZ sensitive to music-based arousal but not picture-based arousal. Stimulus modality itself was predicted from EMGC. Thus, physiological responses to valence were similar across modalities but physiological responses to arousal differed across modalities. These results support the utility of testing for affective markers across modalities within the same experimental setting to reveal how physiological responses are linked to either affect, stimulus modality or both.

  5. Physiological responses to environmental factors related to space flight

    NASA Technical Reports Server (NTRS)

    Pace, N.; Grunbaum, B. W.; Kodama, A. M.; Mains, R. C.; Rahlmann, D. F.

    1975-01-01

    Physiological procedures and instrumentation developed for the measurement of hemodynamic and metabolic parameters during prolonged periods of weightlessness are described along with the physiological response of monkeys to weightlessness. Specific areas examined include: cardiovascular studies; thyroid function; blood oxygen transport; growth and reproduction; excreta analysis for metabolic balance studies; and electrophoretic separation of creatine phosphokinase isoenzymes in human blood.

  6. Environmental cadmium exposure impacts physiological responses in Manila clams.

    PubMed

    Zhao, Liqiang; Zhang, Yu; Liang, Jian; Xu, Xian; Wang, Hua; Yang, Feng; Yan, Xiwu

    2014-06-01

    The physiological responses of marine bivalves to chronic cadmium (Cd) exposure at sub-lethal concentrations have been well documented. As of now, few studies have examined the effect of Cd exposure and subsequent recovery period at environmentally realistic concentrations. In this study, environmentally, Cd exposures were performed to assess the physiological responses of the Manila clam Ruditapes philippinarum. The clams were exposed to waterborne Cd at two environmentally realistic concentrations (4 and 40 μg L(-1)) for 35 days and then allowed to recover for another 35 days. The accumulation and elimination of Cd in R. philippinarum were tissue-specific and dose- and time-dependent. Cd accumulation increased sharply in the digestive gland, and Cd elimination was rapid in the gill. Major physiological responses, including clearance rate, absorption efficiency, respiration rate, excretion rate, oxygen to nitrogen ratio, and scope for growth, were significantly affected by Cd exposure. Yet, the clams exposed to 4-μg L(-1) Cd were able to quickly recover their normal physiological processes and clearly exhibited catch-up growth once they were transferred to clean seawater. Hence, R. philippinarum can exhibit good physiological plasticity when confronted with moderately environmental Cd exposure. All physiological responses measured exhibited a highly significant and generally predictable correlation with tissue Cd concentration, which in turn, reflected environmentally realistic exposure conditions. Our results further confirm that the measurement of physiological responses is a sensitive method for assessing stress at environmentally realistic metal concentrations.

  7. Linking physiological and cellular responses to thermal stress: β-adrenergic blockade reduces the heat shock response in fish.

    PubMed

    Templeman, Nicole M; LeBlanc, Sacha; Perry, Steve F; Currie, Suzanne

    2014-08-01

    When faced with stress, animals use physiological and cellular strategies to preserve homeostasis. We were interested in how these high-level stress responses are integrated at the level of the whole animal. Here, we investigated the capacity of the physiological stress response, and specifically the β-adrenergic response, to affect the induction of the cellular heat shock proteins, HSPs, following a thermal stress in vivo. We predicted that blocking β-adrenergic stimulation during an acute heat stress in the whole animal would result in reduced levels of HSPs in red blood cells (RBCs) of rainbow trout compared to animals where adrenergic signaling remained intact. We first determined that a 1 h heat shock at 25 °C in trout acclimated to 13 °C resulted in RBC adrenergic stimulation as determined by a significant increase in cell swelling, a hallmark of the β-adrenergic response. A whole animal injection with the β2-adrenergic antagonist, ICI-118,551, successfully reduced this heat-induced RBC swelling. The acute heat shock caused a significant induction of HSP70 in RBCs of 13 °C-acclimated trout as well as a significant increase in plasma catecholamines. When heat-shocked fish were treated with ICI-118,551, we observed a significant attenuation of the HSP70 response. We conclude that circulating catecholamines influence the cellular heat shock response in rainbow trout RBCs, demonstrating physiological/hormonal control of the cellular stress response.

  8. The Physiological and Evolutionary Background of Maternal Responsiveness.

    ERIC Educational Resources Information Center

    Rosenblatt, Jay S.

    1989-01-01

    Examines the influence of hormonal factors during pregnancy on maternal responsiveness in infrahuman animals and human beings. Argues that it is likely that maternal behavior in humans has a physiological basis. (PCB)

  9. Personality traits modulate emotional and physiological responses to stress

    PubMed Central

    Childs, Emma; White, Tara L.; de Wit, Harriet

    2014-01-01

    An individual’s susceptibility to psychological and physical disorders associated with chronic stress exposure e.g., cardiovascular and infectious disease, may also be predicted by their reactivity to acute stress. One factor associated with both stress resilience and health outcomes is personality. An understanding of how personality influences responses to acute stress may shed light upon individual differences in susceptibility to chronic stress-linked disease. This study examined relationships between personality and acute responses to stress in 125 healthy adults, using hierarchical linear regression. We assessed personality traits using the Multidimensional Personality Questionnaire (MPQ-BF), and responses to acute stress (cortisol, heart rate, blood pressure, mood) using a standardised laboratory psychosocial stress task, the Trier Social Stress Test (TSST). Individuals with high Negative Emotionality exhibited greater emotional distress and lower blood pressure responses to the TSST. Individuals with high Agentic Positive Emotionality exhibited prolonged heart rate responses to stress, whereas those with high Communal Positive Emotionality exhibited smaller cortisol and blood pressure responses. Separate personality traits differentially predicted emotional, cardiovascular, and cortisol responses to a psychosocial stressor in healthy volunteers. Future research investigating the association of personality with chronic stress-related disease may provide further clues to the relationship between acute stress reactivity and susceptibility to disease. PMID:25036730

  10. Molecular and physiological responses to titanium dioxide ...

    EPA Pesticide Factsheets

    - Changes in tissue transcriptomes and productivity of Arabidopsis thaliana were investigated during exposure of plants to two widely-used engineered metal oxide nanoparticles, titanium dioxide (nano-titanium) and cerium dioxide (nano-cerium). Microarray analyses confirmed that exposure to either nanoparticle altered the transcriptomes of rosette leaves and roots, with comparatively larger numbers of differentially expressed genes (DEGs) found under nano-titania exposure. Nano-titania induced more DEGs in rosette leaves, whereas roots had more DEGs under nano-ceria exposure. MapMan analyses indicated that while nano-titania up-regulated overall and secondary metabolism in both tissues, metabolic processes under nano-ceria remained mostly unchanged. Gene enrichment analysis indicated that both nanoparticles mainly enriched ontology groups such as responses to stress (abiotic and biotic), and defense responses (pathogens), and responses to endogenous stimuli (hormones). Nano-titania specifically induced genes associated with photosynthesis, whereas nano-ceria induced expression of genes related to activating transcription factors, most notably those belonging to the ethylene responsive element binding protein family. Interestingly, there were also increased numbers of rosette leaves and plant biomass under nano-ceria exposure, but not under nano-titania. Other transcriptomic responses did not clearly relate to responses observed at the organism level. This may b

  11. Genetic influences on the neural and physiological bases of acute threat: A research domain criteria (RDoC) perspective.

    PubMed

    Sumner, Jennifer A; Powers, Abigail; Jovanovic, Tanja; Koenen, Karestan C

    2016-01-01

    The NIMH Research Domain Criteria (RDoC) initiative aims to describe key dimensional constructs underlying mental function across multiple units of analysis-from genes to observable behaviors-in order to better understand psychopathology. The acute threat ("fear") construct of the RDoC Negative Valence System has been studied extensively from a translational perspective, and is highly pertinent to numerous psychiatric conditions, including anxiety and trauma-related disorders. We examined genetic contributions to the construct of acute threat at two units of analysis within the RDoC framework: (1) neural circuits and (2) physiology. Specifically, we focused on genetic influences on activation patterns of frontolimbic neural circuitry and on startle, skin conductance, and heart rate responses. Research on the heritability of activation in threat-related frontolimbic neural circuitry is lacking, but physiological indicators of acute threat have been found to be moderately heritable (35-50%). Genetic studies of the neural circuitry and physiology of acute threat have almost exclusively relied on the candidate gene method and, as in the broader psychiatric genetics literature, most findings have failed to replicate. The most robust support has been demonstrated for associations between variation in the serotonin transporter (SLC6A4) and catechol-O-methyltransferase (COMT) genes with threat-related neural activation and physiological responses. However, unbiased genome-wide approaches using very large samples are needed for gene discovery, and these can be accomplished with collaborative consortium-based research efforts, such as those of the Psychiatric Genomics Consortium (PGC) and Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Consortium.

  12. Genetic Influences on the Neural and Physiological Bases of Acute Threat: A Research Domain Criteria (RDoC) Perspective

    PubMed Central

    Sumner, Jennifer A.; Powers, Abigail; Jovanovic, Tanja; Koenen, Karestan C.

    2015-01-01

    The NIMH Research Domain Criteria (RDoC) initiative aims to describe key dimensional constructs underlying mental function across multiple units of analysis—from genes to observable behaviors—in order to better understand psychopathology. The acute threat (“fear”) construct of the RDoC Negative Valence System has been studied extensively from a translational perspective, and is highly pertinent to numerous psychiatric conditions, including anxiety and trauma-related disorders. We examined genetic contributions to the construct of acute threat at two units of analysis within the RDoC framework: 1) neural circuits and 2) physiology. Specifically, we focused on genetic influences on activation patterns of frontolimbic neural circuitry and on startle, skin conductance, and heart rate responses. Research on the heritability of activation in threat-related frontolimbic neural circuitry is lacking, but physiological indicators of acute threat have been found to be moderately heritable (35-50%). Genetic studies of the neural circuitry and physiology of acute threat have almost exclusively relied on the candidate gene method and, as in the broader psychiatric genetics literature, most findings have failed to replicate. The most robust support has been demonstrated for associations between variation in the serotonin transporter (SLC6A4) and catechol-O-methyltransferase (COMT) genes with threat-related neural activation and physiological responses. However, unbiased genome-wide approaches using very large samples are needed for gene discovery, and these can be accomplished with collaborative consortium-based research efforts, such as those of the Psychiatric Genomics Consortium (PGC) and Enhancing Neuro Imaging Genetics through Meta-Analysis (ENIGMA) Consortium. PMID:26377804

  13. Physiological Response to Physical Activity in Children.

    ERIC Educational Resources Information Center

    Gilliam, Thomas B.

    This is a report on research in the field of physical responses of children to strenuous activity. The paper is divided into three subtopics: (1) peak performance measure in children; (2) training effects on children; and (3) importance of physical activity for children. Measurements used are oxygen consumption, ventilation, heart rate, cardiac…

  14. PHYSIOLOGICAL RESPONSES TO LIVE E. COLI ORGANISMS

    DTIC Science & Technology

    shock and shock produced by injection of live E . coli organisms in dogs. A primary purpose of our research has been to determine the effects of...intravenous injections of living E . coli organisms in dogs and monkeys and compare them with responses produced by endotoxin. Hemodynamic changes...pathologic alterations, and metabolic abnormalities have been evaluated in animals receiving lethal and sublethal injections of live E . coli organisms and comparable dosages of purified endotoxin.

  15. Measuring Physiological Stress Responses in Children: Lessons from a Novice

    ERIC Educational Resources Information Center

    Quas, Jodi A.

    2011-01-01

    In this article the author describes challenges associated with integrating physiological measures of stress into developmental research, especially in the domains of memory and cognition. An initial critical challenge concerns how to define stress, which can refer to one or a series of events, a response, the consequence of that response, an…

  16. Cystic fibrosis and physiological responses to exercise.

    PubMed

    Williams, Craig A; Saynor, Zoe L; Tomlinson, Owen W; Barker, Alan R

    2014-12-01

    Cardiopulmonary exercise testing is underutilized within the clinical management of patients with cystic fibrosis. But within the last 5 years, there has been considerable interest in its implementation, which has included deliberations by the European Cystic Fibrosis Society about incorporating this method within the clinical assessment of patients. This review examines the current use of cardiopulmonary exercise testing in assessing the extent and cause(s) of exercise limitation from a pediatric perspective. Examples of the measured parameters and their interpretation are provided. Critical synthesis of recent work in the oxygen uptake (VO2) kinetics response to and following exercise is also discussed, and although identified more as a research tool, its utilization advances researchers understanding of the cardiovascular, respiratory and muscular limitations to exercise tolerance. Finally, exercise and its application in therapeutic interventions are highlighted and a number of recommendations made about the utility of exercise prescription.

  17. Acute physiological stress down-regulates mRNA expressions of growth-related genes in coho salmon.

    PubMed

    Nakano, Toshiki; Afonso, Luis O B; Beckman, Brian R; Iwama, George K; Devlin, Robert H

    2013-01-01

    Growth and development in fish are regulated to a major extent by growth-related factors, such as liver-derived insulin-like growth factor (IGF) -1 in response to pituitary-secreted growth hormone (GH) binding to the GH receptor (GHR). Here, we report on the changes in the expressions of gh, ghr, and igf1 genes and the circulating levels of GH and IGF-1 proteins in juvenile coho salmon (Oncorhynchus kisutch) in response to handling as an acute physiological stressor. Plasma GH levels were not significantly different between stressed fish and prestressed control. Plasma IGF-1 concentrations in stressed fish 1.5 h post-stress were the same as in control fish, but levels in stressed fish decreased significantly 16 h post-stress. Real-time quantitative PCR (qPCR) analysis showed that ghr mRNA levels in pituitary, liver, and muscle decreased gradually in response to the stressor. After exposure to stress, hepatic igf1 expression transiently increased, whereas levels decreased 16 h post-stress. On the other hand, the pituitary gh mRNA level did not change in response to the stressor. These observations indicate that expression of gh, ghr, and igf1 responded differently to stress. Our results show that acute physiological stress can mainly down-regulate the expressions of growth-related genes in coho salmon in vivo. This study also suggests that a relationship between the neuroendocrine stress response and growth-related factors exists in fish.

  18. Acute Physiological Stress Down-Regulates mRNA Expressions of Growth-Related Genes in Coho Salmon

    PubMed Central

    Nakano, Toshiki; Afonso, Luis O. B.; Beckman, Brian R.; Iwama, George K.; Devlin, Robert H.

    2013-01-01

    Growth and development in fish are regulated to a major extent by growth-related factors, such as liver-derived insulin-like growth factor (IGF) -1 in response to pituitary-secreted growth hormone (GH) binding to the GH receptor (GHR). Here, we report on the changes in the expressions of gh, ghr, and igf1 genes and the circulating levels of GH and IGF-1 proteins in juvenile coho salmon (Oncorhynchus kisutch) in response to handling as an acute physiological stressor. Plasma GH levels were not significantly different between stressed fish and prestressed control. Plasma IGF-1 concentrations in stressed fish 1.5 h post-stress were the same as in control fish, but levels in stressed fish decreased significantly 16 h post-stress. Real-time quantitative PCR (qPCR) analysis showed that ghr mRNA levels in pituitary, liver, and muscle decreased gradually in response to the stressor. After exposure to stress, hepatic igf1 expression transiently increased, whereas levels decreased 16 h post-stress. On the other hand, the pituitary gh mRNA level did not change in response to the stressor. These observations indicate that expression of gh, ghr, and igf1 responded differently to stress. Our results show that acute physiological stress can mainly down-regulate the expressions of growth-related genes in coho salmon in vivo. This study also suggests that a relationship between the neuroendocrine stress response and growth-related factors exists in fish. PMID:23990952

  19. Lymphatic Vascular Response to Acute Inflammation

    PubMed Central

    Lachance, Pier-Anne; Hazen, Amy; Sevick-Muraca, Eva M.

    2013-01-01

    During acute inflammation, functioning lymphatics are believed to reduce edema and to provide a transiting route for immune cells, but the extent at which the dermal lymphatic remodeling impacts lymphatic transport or the factors regulating these changes remains unclear. Herein we quantify the increase in lymphatic endothelial cells (LECs) and examine the expression of pro-angiogenenic and lymphangiogenic factors during acute cutaneous hypersensitivity (CHS). We found that LECs actively proliferate during CHS but that this proliferation does not affect the lymphatic vessel density. Instead, lymphatic remodeling is accompanied by lymphatic vessel leakiness and lower ejection of lymph fluid, which is observed only in the proximal lymphatic vessel draining the inflamed area. LECs and the immune cells release growth factors and cytokines during inflammation, which impact the lymphatic microenvironment and function. We identified that FGF-2, PLGF-2, HGF, EGF, and KC/CXCL17 are differentially expressed within tissues during acute CHS, but both VEGF-C and VEGF-D levels do not significantly change. Our results indicate that VEGF-C and VEGF-D are not the only players and other factors may be responsible for the LECs proliferation and altered lymphatic function in acute CHS. PMID:24086691

  20. Physiological responses to repeated transportation of gestating Brahman cows

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The transportation process acts as a stressor with adverse effects on animal health and performance. The purpose of this study was to examine physiological responses to repeated transportation of gestating Brahman cows, previously classified as mature cows, into temperament groups of calm, moderate,...

  1. Reversible acute axonal polyneuropathy associated with Wernicke-Korsakoff syndrome: impaired physiological nerve conduction due to thiamine deficiency?

    PubMed

    Ishibashi, S; Yokota, T; Shiojiri, T; Matunaga, T; Tanaka, H; Nishina, K; Hirota, H; Inaba, A; Yamada, M; Kanda, T; Mizusawa, H

    2003-05-01

    Acute axonal polyneuropathy and Wernicke-Korsakoff encephalopathy developed simultaneously in three patients. Nerve conduction studies (NCS) detected markedly decreased compound muscle action potentials (CMAPs) and sensory nerve action potentials (SNAPs) with minimal conduction slowing; sympathetic skin responses (SSRs) were also notably decreased. Sural nerve biopsies showed only mild axonal degeneration with scattered myelin ovoid formation. The symptoms of neuropathy lessened within two weeks after an intravenous thiamine infusion. CMAPs, SNAPs, and SSRs also increased considerably. We suggest that this is a new type of peripheral nerve impairment: physiological conduction failure with minimal conduction delay due to thiamine deficiency.

  2. An integrated physiology model to study regional lung damage effects and the physiologic response

    PubMed Central

    2014-01-01

    Background This work expands upon a previously developed exercise dynamic physiology model (DPM) with the addition of an anatomic pulmonary system in order to quantify the impact of lung damage on oxygen transport and physical performance decrement. Methods A pulmonary model is derived with an anatomic structure based on morphometric measurements, accounting for heterogeneous ventilation and perfusion observed experimentally. The model is incorporated into an existing exercise physiology model; the combined system is validated using human exercise data. Pulmonary damage from blast, blunt trauma, and chemical injury is quantified in the model based on lung fluid infiltration (edema) which reduces oxygen delivery to the blood. The pulmonary damage component is derived and calibrated based on published animal experiments; scaling laws are used to predict the human response to lung injury in terms of physical performance decrement. Results The augmented dynamic physiology model (DPM) accurately predicted the human response to hypoxia, altitude, and exercise observed experimentally. The pulmonary damage parameters (shunt and diffusing capacity reduction) were fit to experimental animal data obtained in blast, blunt trauma, and chemical damage studies which link lung damage to lung weight change; the model is able to predict the reduced oxygen delivery in damage conditions. The model accurately estimates physical performance reduction with pulmonary damage. Conclusions We have developed a physiologically-based mathematical model to predict performance decrement endpoints in the presence of thoracic damage; simulations can be extended to estimate human performance and escape in extreme situations. PMID:25044032

  3. Acute dissociation predicts rapid habituation of skin conductance responses to aversive auditory probes.

    PubMed

    Giesbrecht, Timo; Merckelbach, Harald; ter Burg, Linda; Cima, Maaike; Simeon, Daphne

    2008-04-01

    The present study examined how acute dissociation, trait-like dissociative symptoms, and physiological reactivity relate to each other. Sixty-nine undergraduate students were exposed to 14 aversive auditory probes, while their skin conductance responses were measured. A combination of self-reported anxiety and trait-like dissociation was found to predict variability in peritraumatic dissociation levels induced by the aversive probes. Furthermore, high levels of acute dissociation were associated with faster habituation of skin conductance responding, while trait-like dissociation was unrelated to habituation. Interestingly, individuals who reported childhood trauma displayed elevated skin conductance responses. Our findings contribute to the growing body of evidence indicating that subjective feelings of acute dissociation have their objective concomitants, notably fast habituation of physiologic responses.

  4. Effects of multiple acute stressors on the predator avoidance ability and physiology of juvenile Chinook salmon

    USGS Publications Warehouse

    Mesa, Matthew G.

    1994-01-01

    Northern squaw fish Ptychocheilus oregonensis are the predominant predators of juvenile Pacific salmonids Oncorhynchus spp. in the Columbia River, and their predation rates are greatest just below dams. Because juvenile salmonids are commonly subjected to multiple stressors at dams in the course of their seaward migration, high predation rates below dams may be due in part to an increase in the vulnerability of stressed fish. I conducted laboratory experiments to examine the predator avoidance ability and physiological stress responses of juvenile chinook salmon O. tshawytscha subjected to treatments (stressors) designed to simulate routine hatchery practices (multiple handlings) or dam passage (multiple agitations). Both stressors resulted in lethargic behavior in the fish, and agitation also caused disorieniation and occasional injury. When equal numbers of stressed and unstressed fish were exposed to northern squawfish for up to 1 h, significantly more stressed fish were eaten, but this effect was not evident during longer exposures. The lack of differential predation in trials lasting up to 24 h can be explained by the rapid development of schooling behavior in the prey, but other possibilities exist, such as changing ratios of stressed and unstressed prey over time. Concentrations of plasma cortisol, glucose, and lactate in fish subjected to multiple stressors were similar and sometimes cumulative, returned to prestress levels within 6-24 h, and correlated poorly with predator avoidance ability. My results suggest that juvenile salmonids are capable of avoiding predators within 1 h after being subjected to multiple acute stressors even though physiological homeostasis may be altered for up to 24 h. Therefore, because juvenile salmonids typically reside in lailrace areas for only a short time after dam passage, measures aimed at reducing physical stress or protecting them as they migrate through dam tailraces may help alleviate the relatively intense predation

  5. Physiological responses to prolonged bed rest and fluid immersion in humans

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.

    1984-01-01

    For many centuries, physicians have used prolonged rest in bed and immersion in water in the treatment of ailments and disease. Both treatments have positive remedial effects. However, adverse physiological responses become evident when patients return to their normal daily activities. The present investigation is concerned with an analysis of the physiological changes during bed rest and the effects produced by water immersion. It is found that abrupt changes in body position related to bed rest cause acute changes in fluid compartment volumes. Attention is given to fluid shifts and body composition, renal function and diuresis, calcium and phosphorus metabolism, and orthostatic tolerance. In a discussion of water immersion, fluid shifts are considered along with cardiovascular-respiratory responses, renal function, and natriuretic and diuretic factors.

  6. Physiological responses induced by emotion-eliciting films.

    PubMed

    Fernández, Cristina; Pascual, Juan C; Soler, Joaquim; Elices, Matilde; Portella, Maria J; Fernández-Abascal, Enrique

    2012-06-01

    Emotion-eliciting films are commonly used to evoke subjective emotional responses in experimental settings. The main aim of the present study was to investigate whether a set of film clips with discrete emotions were capable to elicit measurable objective physiological responses. The convergence between subjective and objective measures was evaluated. Finally, the effect of gender on emotional responses was investigated. A sample of 123 subjects participated in the study. Individuals were asked to view a set of emotional film clips capable to induce seven emotions: anger, fear, sadness, disgust, amusement, tenderness and neutral state. Skin conductance level (SCL), heart rate (HR) and subjective emotional responses were measured for each film clip. In comparison with neutral films, SCL was significantly increased after viewing fear films, and HR was also significantly incremented for anger and fear films. Physiological variations were associated with arousal measures indicating a convergence between subjective and objective reactions. Women appeared to display significantly greater SCL and HR responses for films inducing sadness. The findings suggest that physiological activation would be more easily induced by emotion-eliciting films that tap into emotions with higher subjective arousal such as anger and fear.

  7. Repeated thermal stressor causes chronic elevation of baseline corticosterone and suppresses the physiological endocrine sensitivity to acute stressor in the cane toad (Rhinella marina).

    PubMed

    Narayan, Edward J; Hero, Jean-Marc

    2014-04-01

    Extreme environmental temperature could impact the physiology and ecology of animals. The stress endocrine axis provides necessary physiological stress response to acute (day-day) stressors. Presently, there are no empirical evidences showing that exposure to extreme thermal stressor could cause chronic stress in amphibians. This could also modulate the physiological endocrine sensitivity to acute stressors and have serious implications for stress coping in amphibians, particularly those living in fragmented and disease prone environments. We addressed this important question using the cane toad (Rhinella marina) model from its introduced range in Queensland, Australia. We quantified their physiological endocrine sensitivity to a standard acute (capture and handling) stressor after exposing the cane toads to thermal shock at 35°C for 30min daily for 34 days. Corticosterone (CORT) responses to the capture and handling protocol were measured on three sampling intervals (days 14, 24, and 34) to determine whether the physiological endocrine sensitivity was maintained or modulated over-time. Two control groups (C1 for baseline CORT measurement only and C2 acute handled only) and two temperature treatment groups (T1 received daily thermal shock up to day 14 only and a recovery phase of 20 days and T2 received thermal shock daily for 34 days). Results showed that baseline CORT levels remained high on day 14 (combined effect of capture, captivity and thermal stress) for both T1 and T2. Furthermore, baseline CORT levels decreased for T1 once the thermal shock was removed after day 14 and returned to baseline by day 29. On the contrary, baseline CORT levels kept on increasing for T2 over the 34 days of daily thermal shocks. Furthermore, the magnitudes of the acute CORT responses or physiological endocrine sensitivity were consistently high for both C1 and T1. However, acute CORT responses for T2 toads were dramatically reduced between days 24 and 34. These novel findings

  8. Applications of Flow Cytometry to Characterize Bacterial Physiological Responses

    PubMed Central

    Contreras-Garduño, Jorge A.; Pedraza-Reyes, Mario

    2014-01-01

    Although reports of flow cytometry (FCM) applied to bacterial analysis are increasing, studies of FCM related to human cells still vastly outnumber other reports. However, current advances in FCM combined with a new generation of cellular reporter probes have made this technique suitable for analyzing physiological responses in bacteria. We review how FCM has been applied to characterize distinct physiological conditions in bacteria including responses to antibiotics and other cytotoxic chemicals and physical factors, pathogen-host interactions, cell differentiation during biofilm formation, and the mechanisms governing development pathways such as sporulation. Since FCM is suitable for performing studies at the single-cell level, we describe how this powerful technique has yielded invaluable information about the heterogeneous distribution of differently and even specialized responding cells and how it may help to provide insights about how cell interaction takes place in complex structures, such as those that prevail in bacterial biofilms. PMID:25276788

  9. Bordetella bronchiseptica responses to physiological reactive nitrogen and oxygen stresses

    PubMed Central

    Omsland, Anders; Miranda, Katrina M.; Friedman, Richard L.; Boitano, Scott

    2008-01-01

    Bordetella bronchiseptica can establish prolonged airway infection consistent with a highly developed ability to evade mammalian host immune responses. Upon initial interaction with the host upper respiratory tract mucosa, B. bronchiseptica are subjected to antimicrobial reactive nitrogen species (RNS) and reactive oxygen species (ROS), effector molecules of the innate immune system. However, the responses of B. bronchiseptica to redox species at physiologically relevant concentrations (nM-µM) have not been investigated. Using predicted physiological concentrations of nitric oxide (NO), superoxide (O2.−) and hydrogen peroxide (H2O2) on low numbers of colony forming units (CFU) of B. bronchiseptica, all redox active species displayed dose-dependent antimicrobial activity. Susceptibility to individual redox active species was significantly increased upon introduction of a second species at sub-antimicrobial concentrations. An increased bacteriostatic activity of NO was observed relative to H2O2. The understanding of Bordetella responses to physiologically relevant levels of exogenous RNS and ROS will aid in defining the role of endogenous production of these molecules in host innate immunity against Bordetella and other respiratory pathogens. PMID:18462394

  10. Fight-flight or freeze-hide? Personality and metabolic phenotype mediate physiological defence responses in flatfish.

    PubMed

    Rupia, Emmanuel J; Binning, Sandra A; Roche, Dominique G; Lu, Weiqun

    2016-07-01

    Survival depends on appropriate behavioural and physiological responses to danger. In addition to active 'fight-flight' defence responses, a passive 'freeze-hide' response is adaptive in some contexts. However, the physiological mechanisms determining which individuals choose a given defence response remain poorly understood. We examined the relationships among personality, metabolic performance and physiological stress responses across an environmental gradient in the olive flounder, Paralichthys olivaceus. We employed four behavioural assays to document the existence of two distinct behavioural types ('bold' and 'shy') in this species. We found consistent metabolic differences between individuals of a given behavioural type across an environmental gradient: shy individuals had overall lower aerobic scope, maximum metabolic rate and standard metabolic rate than bold individuals in both high (25 ppt) and low (3 ppt) salinity. These behavioural and metabolic differences translated into divergent physiological responses during acute stress: shy individuals adopted a passive 'freeze-hide' response by reducing their oxygen consumption rates (akin to shallow breathing) whereas bold individuals adopted an active 'fight-flight' response by increasing their rates of respiration. These distinct defence strategies were repeatable within individuals between salinity treatments. Although it has been suggested theoretically, this is the first empirical evidence that the metabolic response to stressful situations differs between bold and shy individuals. Our results emphasize the importance of incorporating physiological measures to understand the mechanisms driving persistent inter-individual differences in animals.

  11. Orthostatic haemodynamic responses in acute stroke

    PubMed Central

    Panayiotou, B; Reid, J; Fotherby, M; Crome, P

    1999-01-01

    Little is known about orthostatic blood pressure regulation in acute stroke. We determined postural haemodynamic responses in 40 patients with acute stroke (mild or moderate severity) and 40 non-stroke control in-patients, at two days (`Day 1') and one week (`Week 1') post-admission. Following a 10-minute supine rest and baseline readings, subjects sat up and blood pressure and heart rate were taken for 5 minutes. The procedure was repeated with subjects moving from supine to the standing posture. Haemodynamic changes from supine data were analysed. On standing up, the control group had a transient significant fall in mean arterial blood pressure on Day 1 but not Week 1. No significant changes were seen on either day when sitting up. In contrast to controls, the stroke group showed increases in mean arterial blood pressure on moving from supine to the sitting and standing positions on both days. Persistent postural hypotension defined as ⩾20 mmHg systolic fall occurred in <10% of either of the study groups on both days. Sitting and standing heart rates in both groups were significantly faster than supine heart rate on both days. The orthostatic blood pressure elevation is consistent with sympathetic nervous system overactivity which has been reported in acute stroke. Upright positioning as part of early rehabilitation and mobilisation following mild-to-moderate stroke would, therefore, not predispose to detrimental postural reductions in blood pressure.


Keywords: stroke; orthostatic hypotension; hypotension PMID:10715760

  12. Acute psychological stress induces short-term variable immune response.

    PubMed

    Breen, Michael S; Beliakova-Bethell, Nadejda; Mujica-Parodi, Lilianne R; Carlson, Joshua M; Ensign, Wayne Y; Woelk, Christopher H; Rana, Brinda K

    2016-03-01

    In spite of advances in understanding the cross-talk between the peripheral immune system and the brain, the molecular mechanisms underlying the rapid adaptation of the immune system to an acute psychological stressor remain largely unknown. Conventional approaches to classify molecular factors mediating these responses have targeted relatively few biological measurements or explored cross-sectional study designs, and therefore have restricted characterization of stress-immune interactions. This exploratory study analyzed transcriptional profiles and flow cytometric data of peripheral blood leukocytes with physiological (endocrine, autonomic) measurements collected throughout the sequence of events leading up to, during, and after short-term exposure to physical danger in humans. Immediate immunomodulation to acute psychological stress was defined as a short-term selective up-regulation of natural killer (NK) cell-associated cytotoxic and IL-12 mediated signaling genes that correlated with increased cortisol, catecholamines and NK cells into the periphery. In parallel, we observed down-regulation of innate immune toll-like receptor genes and genes of the MyD88-dependent signaling pathway. Correcting gene expression for an influx of NK cells revealed a molecular signature specific to the adrenal cortex. Subsequently, focusing analyses on discrete groups of coordinately expressed genes (modules) throughout the time-series revealed immune stress responses in modules associated to immune/defense response, response to wounding, cytokine production, TCR signaling and NK cell cytotoxicity which differed between males and females. These results offer a spring-board for future research towards improved treatment of stress-related disease including the impact of stress on cardiovascular and autoimmune disorders, and identifies an immune mechanism by which vulnerabilities to these diseases may be gender-specific.

  13. Physiologic responses of pilots flying high-performance aircraft.

    PubMed

    Comens, P; Reed, D; Mette, M

    1987-03-01

    This study deals with the physiologic responses to stress in F-4 fighter pilots and aircrew engaged in surface attack training (SAT) missions. Blood levels of HDL-cholesterol, LDH and LDH isoenzymes, CPK, and myoglobin were determined before and after each mission. Continuous EKG and transcutaneous PO2 recordings were made during briefing, preflight, and inflight. The personal history and habits of each participant were recorded. Each mission consisted of six successive bomb deliveries at 80-s intervals and at increasingly steep dive angles, each terminating in 5.5-6 +Gz during pull-up. Results revealed no apparent effect on HDL, COP isoenzymes, and LDH isoenzymes. Many myoglobin levels dropped as much as 50%. EKG recordings revealed ST elevations, ST depressions, T wave inversions, and marked sinus arrhythmias in some, while others showed increases in cardiac rate. Pilots flying these SAT missions in F-4C aircraft were found not to be significantly physiologically stressed.

  14. Dynamics of food availability, body condition and physiological stress response in breeding Black-legged Kittiwakes

    USGS Publications Warehouse

    Kitaysky, A.S.; Wingfield, J.C.; Piatt, J.F.

    1999-01-01

    1. The seasonal dynamics of body condition (BC), circulating corticosterone levels (baseline, BL) and the adrenocortical response to acute stress (SR) were examined in long-lived Black-legged Kittiwakes, Rissa tridactyla, breeding at Duck (food-poor colony) and Gull (food-rich colony) Islands in lower Cook Inlet, Alaska. It was tested whether the dynamics of corticosterone levels reflect a seasonal change in bird physiological condition due to reproduction and/or variation in foraging conditions. 2. BC declined seasonally, and the decline was more pronounced in birds at the food-poor colony. BL and SR levels of corticosterone rose steadily through the reproductive season, and BL levels were significantly higher in birds on Duck island compared with those on Gull Island. During the egg-laying and chick-rearing stages, birds had lower SR on Duck Island than on Gull Island. 3. The results suggest that, in addition to a seasonal change in bird physiology during reproduction, local ecological factors such as food availability affect circulating levels of corticosterone and adrenal response to acute stress.

  15. Exertional rhabdomyolysis: physiological response or manifestation of an underlying myopathy?

    PubMed Central

    Scalco, Renata S; Snoeck, Marc; Quinlivan, Ros; Treves, Susan; Laforét, Pascal; Jungbluth, Heinz; Voermans, Nicol C

    2016-01-01

    Exertional rhabdomyolysis is characterised by muscle breakdown associated with strenuous exercise or normal exercise under extreme circumstances. Key features are severe muscle pain and sudden transient elevation of serum creatine kinase (CK) levels with or without associated myoglobinuria. Mild cases may remain unnoticed or undiagnosed. Exertional rhabdomyolysis is well described among athletes and military personnel, but may occur in anybody exposed to unaccustomed exercise. In contrast, exertional rhabdomyolysis may be the first manifestation of a genetic muscle disease that lowers the exercise threshold for developing muscle breakdown. Repeated episodes of exertional rhabdomyolysis should raise the suspicion of such an underlying disorder, in particular in individuals in whom the severity of the rhabdomyolysis episodes exceeds the expected response to the exercise performed. The present review aims to provide a practical guideline for the acute management and postepisode counselling of patients with exertional rhabdomyolysis, with a particular emphasis on when to suspect an underlying genetic disorder. The pathophysiology and its clinical features are reviewed, emphasising four main stepwise approaches: (1) the clinical significance of an acute episode, (2) risks of renal impairment, (3) clinical indicators of an underlying genetic disorders and (4) when and how to recommence sport activity following an acute episode of rhabdomyolysis. Genetic backgrounds that appear to be associated with both enhanced athletic performance and increased rhabdomyolysis risk are briefly reviewed. PMID:27900193

  16. Perceptual and Physiological Responses to Jackson Pollock's Fractals.

    PubMed

    Taylor, Richard P; Spehar, Branka; Van Donkelaar, Paul; Hagerhall, Caroline M

    2011-01-01

    Fractals have been very successful in quantifying the visual complexity exhibited by many natural patterns, and have captured the imagination of scientists and artists alike. Our research has shown that the poured patterns of the American abstract painter Jackson Pollock are also fractal. This discovery raises an intriguing possibility - are the visual characteristics of fractals responsible for the long-term appeal of Pollock's work? To address this question, we have conducted 10 years of scientific investigation of human response to fractals and here we present, for the first time, a review of this research that examines the inter-relationship between the various results. The investigations include eye tracking, visual preference, skin conductance, and EEG measurement techniques. We discuss the artistic implications of the positive perceptual and physiological responses to fractal patterns.

  17. Perceptual and Physiological Responses to Jackson Pollock's Fractals

    PubMed Central

    Taylor, Richard P.; Spehar, Branka; Van Donkelaar, Paul; Hagerhall, Caroline M.

    2011-01-01

    Fractals have been very successful in quantifying the visual complexity exhibited by many natural patterns, and have captured the imagination of scientists and artists alike. Our research has shown that the poured patterns of the American abstract painter Jackson Pollock are also fractal. This discovery raises an intriguing possibility – are the visual characteristics of fractals responsible for the long-term appeal of Pollock's work? To address this question, we have conducted 10 years of scientific investigation of human response to fractals and here we present, for the first time, a review of this research that examines the inter-relationship between the various results. The investigations include eye tracking, visual preference, skin conductance, and EEG measurement techniques. We discuss the artistic implications of the positive perceptual and physiological responses to fractal patterns. PMID:21734876

  18. [Physiological ecology responses of Scutellaria baicalensis to drought and rewatering].

    PubMed

    Zhang, Yong-Gang; Han, Mei; Jiang, Xue; Zhao, Sheng-Nan; Yang, Li-Min

    2013-11-01

    To study the physiological ecology responses of Scutellaria baicalensis to drought and rewatering of short period, we tested and analyzed photosynthesis and chlorophyll fluorescence parameters of S. baicalensis leaves processed by different ways of water treatment in drought and rewatering period, characteristic indexes of physiology and biochemistry of root SOD, POD, PAL, C4H, etc. and accumulation dynamic change of root baicalin and baicalein. The result showed that along with the worsening drought, P(n), T(r), G(s) and F(v)/F(m) of S. baicalensis declined in different water supply, and F(o) increased. The response of SOD and POD's activity in S. baicalensis root to drought in I and II was earlier than it in III. The response time and increase range of baicalin accumulation existed differences in different water supply, and the indexes regained after rewatering. Therefore, photosynthesis of S. baicalensis changed and it destroyed the antioxidant metabolism balance when soil water content decreased resulting from drought. The synergistic effect of defence mechanism launched by S. baicalensis, SOD, POD, PAL, C4H, baicalin and baicalein reduced active oxygen's damage to the cell.

  19. Physiological imaging of electrical trauma and therapeutic responses

    NASA Astrophysics Data System (ADS)

    Chen, Chin-Tu; Matthews, K.; Aarsvold, John N.; Mintzer, Robert A.; Yasillo, Nicholas J.; Hannig, Jurgen; Capelli-Schellpfefer, M.; Cooper, Malcolm; Lee, Raphael C.

    2000-04-01

    In victims of electrical trauma, electroporation of cell membrane, in which lipid bilayer is permeabilized by thermal and electrical forces, is thought to be a substantial cause of tissue damage. It has been suggested that certain mild surfactant in low concentration could induce sealing of permeabilized lipid bilayers, thus repairing cell membranes that had not been extensively damaged. With an animal model of electrically injured hind limb of rats, we have demonstrated and validated the use of radiotracer imaging technique to assess the physiology of the damaged tissues after electrical shock and of their repairs after applying surfactant as a therapeutic strategy. For example, using Tc-99m labeled pyrophosphate (PYP), which follows calcium in cellular function and is known to accumulate in damaged tissues, we have established a physiological imaging approach for assessment of the extent of tissue injury for diagnosis and surgical planning, as well as for evaluation of responses to therapy. With the use of a small, hand-held, miniature gamma camera, this physiological imaging method can be employed at patient's bedside and even in the field, for example, at accident site or during transfer for emergency care, rapid diagnosis, and prompt treatment in order to maximize the chance for tissue survival.

  20. Circadian rhythms of visual accommodation responses and physiological correlations.

    NASA Technical Reports Server (NTRS)

    Murphy, M. R.; Randle, R. J.; Williams, B. A.

    1972-01-01

    Use of a recently developed servocontrolled infrared optometer to continuously record the state of monocular focus while subjects viewed a visual target for which the stimulus to focus was systematically varied. Calculated parameters form recorded data - e.g., speeds of accommodation to approaching and receding targets, magnitude of accommodation to step changes in target distance, and amplitude and phase lag of response to sinusoidally varying stimuli were submitted to periodicity analyses. Ear canal temperature (ECT) and heart rate (HR) rhythms were also recorded for physiological correlation with accommodation rhythms. HR demonstrated a 24-hr rhythm, but ECT data did not.

  1. Physiological responses at short distances from a parametric speaker.

    PubMed

    Lee, Soomin; Shimomura, Yoshihiro; Katsuura, Tetsuo

    2012-06-13

    In recent years, parametric speakers have been used in various circumstances. In our previous studies, we verified that the physiological burden of the sound of parametric speaker set at 2.6 m from the subjects was lower than that of the general speaker. However, nothing has yet been demonstrated about the effects of the sound of a parametric speaker at the shorter distance between parametric speakers the human body. Therefore, we studied this effect on physiological functions and task performance. Nine male subjects participated in this study. They completed three consecutive sessions: a 20-minute quiet period as a baseline, a 30-minute mental task period with general speakers or parametric speakers, and a 20-minute recovery period. We measured electrocardiogram (ECG) photoplethysmogram (PTG), electroencephalogram (EEG), systolic and diastolic blood pressure. Four experiments, one with a speaker condition (general speaker and parametric speaker), the other with a distance condition (0.3 m and 1.0 m), were conducted respectively at the same time of day on separate days. To examine the effects of the speaker and distance, three-way repeated measures ANOVA (speaker factor x distance factor x time factor) were conducted. In conclusion, we found that the physiological responses were not significantly different between the speaker condition and the distance condition. Meanwhile, it was shown that the physiological burdens increased with progress in time independently of speaker condition and distance condition. In summary, the effects of the parametric speaker at the 2.6 m distance were not obtained at the distance of 1 m or less.

  2. Physiology

    ERIC Educational Resources Information Center

    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…

  3. Validation of a novel, physiologic model of experimental acute pancreatitis in the mouse

    PubMed Central

    Ziegler, Kathryn M; Wade, Terence E; Wang, Sue; Swartz-Basile, Deborah A; Pitt, Henry A; Zyromski, Nicholas J

    2011-01-01

    Background: Many experimental models of acute pancreatitis suffer from lack of clinical relevance. We sought to validate a recently reported murine model of acute pancreatitis that more closely represents the physiology of human biliary pancreatitis. Methods: Mice (C57BL/6J n=6 and CF-1 n=8) underwent infusion of 50μl of 5% sodium taurocholate (NaT) or 50μl of normal saline (NaCl) directly into the pancreatic duct. Twenty-four hours later, pancreatitis severity was graded histologically by three independent observers, and pancreatic tissue concentration of interleukin-6 (IL-6) and monocyte chemoattractant protein-1 (MCP-1) were determined by ELISA. Results: Twenty four hours after retrograde injection, the total pancreatitis score was significantly greater in mice infused with NaT than in those infused with NaCl (6.3 ± 1.2 vs. 1.2 ± 0.4, p<0.05). In addition, the inflammatory mediators IL-6 and MCP-1 were increased in the NaT group relative to the NaCl group. Discussion: Retrograde pancreatic duct infusion of sodium taurocholate induces acute pancreatitis in the mouse. This model is likely representative of human biliary pancreatitis pathophysiology, and therefore provides a powerful tool with which to elucidate basic mechanisms underlying the pathogenesis of acute pancreatitis. PMID:21416058

  4. Physiology is pivotal for interactions between salinity and acute copper toxicity to fish and invertebrates.

    PubMed

    Grosell, M; Blanchard, J; Brix, K V; Gerdes, R

    2007-08-30

    The present paper presents original data and a review of the copper (Cu) toxicity literature for estuarine and marine environments. For the first time, acute Cu toxicity across the full salinity range was determined. Killifish, Fundulus heteroclitus, eggs were hatched in freshwater (FW), 2.5, 5, 10, 15, 22 and 35 ppt (seawater, SW) and juveniles were allowed to acclimate for 7 days prior to acute toxicity testing. Sensitivity was highest in FW (96 h LC50: 18 microg/l), followed by SW (96 h LC50: 294 microg/l) with fish at intermediate salinities being the most tolerant (96 h LC50 > 963 microg/l at 10 ppt). This approximately 50-fold, non-linear variation in sensitivity could not be accounted for by Cu speciation or competition among cations but can be explained by physiology. The relative Na(+) gradient from the blood plasma to the water is greatest in FW followed by SW and is smallest at 10 ppt. Regression of Cu toxicity versus the equilibrium potential for Na(+), which reflects the relative Na(+) gradient, revealed that 93% of the variation can be attributed to Na(+) gradients and thus osmoregulatory physiology. Examination of the existing literature on acute Cu toxicity in SW (defined as >25 ppt) confirmed that early life stages generally are most sensitive but this pattern may be attributable to size rather than developmental stage. Regardless of developmental stage and phylogeny, size clearly matters for Cu sensitivity. The existing literature on the influence of salinity on acute Cu toxicity as well as studies of mechanisms of Cu toxicity in fish and invertebrates are reviewed.

  5. Acute amygdaloid response to systemic inflammation.

    PubMed

    Engler, Harald; Doenlen, Raphael; Engler, Andrea; Riether, Carsten; Prager, Geraldine; Niemi, Maj-Britt; Pacheco-López, Gustavo; Krügel, Ute; Schedlowski, Manfred

    2011-10-01

    The amygdala, a group of nuclei located in the medial temporal lobe, is a key limbic structure involved in mood regulation, associative learning, and modulation of cognitive functions. Functional neuroanatomical studies suggest that this brain region plays also an important role in the central integration of afferent signals from the peripheral immune system. In the present study, intracerebral electroencephalography and microdialysis were employed to investigate the electrophysiological and neurochemical consequences of systemic immune activation in the amygdala of freely moving rats. Intraperitoneal administration of bacterial lipopolysaccharide (100 μg/kg) induced with a latency of about 2 h a significant increase in amygdaloid neuronal activity and a substantial rise in extracellular noradrenaline levels. Activated neurons in the amygdaloid complex, identified by c-Fos immunohistochemistry, were mainly located in the central nucleus and, to a lesser extent, in the basolateral nucleus of the amygdala. Gene expression analysis in micropunches of the amygdala revealed that endotoxin administration induced a strong time-dependent increase in IL-1β, IL-6, and TNF-α mRNA levels indicating that these cytokines are de novo synthesized in the amygdala in response to peripheral immune activation. The changes in amygdaloid activity were timely related to an increase in anxiety-like behavior and decreased locomotor activity and exploration in the open-field. Taken together, these data give novel insights into different features of the acute amygdaloid response during experimental inflammation and provides further evidence that the amygdala integrates immune-derived information to coordinate behavioral and autonomic responses.

  6. Physiological Response of Orchids to Mealybugs (Hemiptera: Pseudococcidae) Infestation.

    PubMed

    Kmieć, K; Kot, I; Golan, K; Górska-Drabik, E; Łagowska, B; Rubinowska, K; Michałek, W

    2016-10-25

    The harmfulness of mealybugs resulting from sucking plant sap, secreting honeydew, and transmitting plant viruses can give them the status of serious pests. This study documents the influence of Pseudococcus maritimus (Ehrhorn) and Pseudococcus longispinus (Targioni Tozzetti) infestation on alterations in selected physiological parameters of Phalaenopsis x hybridum 'Innocence'. The condition of the cytoplasmic membranes was expressed as the value of thiobarbituric acid reactive substances. We have determined changes in the activities of catalase and guaiacol peroxidase and measured the following chlorophyll fluorescence parameters: maximum quantum yield of photosystem II (Fv/Fm), effective quantum yield (Y), photochemical quenching (qP), and nonphotochemical quenching (qN). The strongest physiological response of orchids was recorded in the initial period of mealybugs infestation. Prolonged insect feeding suppressed lipid peroxidation, peroxidase and catalase activity, as well as photosynthesis photochemistry. The pattern of changes was dependent on mealybug species. This indicated the complexity of the processes responsible for plant tolerance. Data generated in this study have provided a better understanding of the impact of two mealybug species infestation on Phalaenopsis and should be useful in developing pest management strategies.

  7. Evaluating physiological responses of plants to salinity stress

    PubMed Central

    Negrão, S.; Schmöckel, S. M.; Tester, M.

    2017-01-01

    Background Because soil salinity is a major abiotic constraint affecting crop yield, much research has been conducted to develop plants with improved salinity tolerance. Salinity stress impacts many aspects of a plant’s physiology, making it difficult to study in toto. Instead, it is more tractable to dissect the plant’s response into traits that are hypothesized to be involved in the overall tolerance of the plant to salinity. Scope and conclusions We discuss how to quantify the impact of salinity on different traits, such as relative growth rate, water relations, transpiration, transpiration use efficiency, ionic relations, photosynthesis, senescence, yield and yield components. We also suggest some guidelines to assist with the selection of appropriate experimental systems, imposition of salinity stress, and obtaining and analysing relevant physiological data using appropriate indices. We illustrate how these indices can be used to identify relationships amongst the proposed traits to identify which traits are the most important contributors to salinity tolerance. Salinity tolerance is complex and involves many genes, but progress has been made in studying the mechanisms underlying a plant’s response to salinity. Nevertheless, several previous studies on salinity tolerance could have benefited from improved experimental design. We hope that this paper will provide pertinent information to researchers on performing proficient assays and interpreting results from salinity tolerance experiments. PMID:27707746

  8. Condition-dependent physiological and behavioural responses to anthropogenic noise.

    PubMed

    Purser, Julia; Bruintjes, Rick; Simpson, Stephen D; Radford, Andrew N

    2016-03-01

    Anthropogenic (man-made) noise, a global pollutant of international concern, is known to affect the physiology and behaviour of a range of organisms. However, experimental studies have tended to focus on trait means; intra-population variation in responses are likely, but have rarely been explored. Here we use established experimental methods to demonstrate a condition-dependent effect of additional noise. We show that juvenile European eels (Anguilla anguilla) in good condition do not respond differently to playbacks of ambient coastal noise and coastal noise with passing ships. By contrast, the additional noise of ship passes caused an increase in ventilation rate and a decrease in startling to a looming predatory stimulus in poor condition eels. Intra-population variation in responses to noise has important implications both for population dynamics and the planning of mitigation measures.

  9. Modeling physiological responses of soil microbes to drought (Invited)

    NASA Astrophysics Data System (ADS)

    Manzoni, S.; Katul, G. G.; Porporato, A. M.; Schaeffer, S. M.; Schimel, J.

    2013-12-01

    Biogeochemical models predict soil carbon (C) under varying environmental conditions, aiming to disentangle the effects of predicted changes in temperature and moisture regimes on C storage. While much work focuses on temperature sensitivity of decomposition, relatively less is known about decomposer responses to changes in soil moisture. Heterotrophic respiration is known to decline as soils become drier, but the underlying physiological mechanisms are not clear and rarely accounted for in models. In particular, we ask: what are the effects of different drought response strategies on C storage potential and the shape of the respiration-moisture relation? We have developed a process-based model to address these questions, including the main physiological responses thought to play a role under varying moisture conditions: i) dormancy, ii) patterns of extra-cellular enzyme production, and iii) osmoregulation. We show that these different drought response strategies play a major role in the long-term partitioning of soil C among stable and labile pools. In very dry conditions, microbes shifting to dormant state tend to favor long-term (steady state) accumulation of stable C at the expenses of microbial biomass, while increasing investment in enzymes leads to accumulation of dissolved organic C, which in turn may partly overcome the diffusion limitations imposed by dry soils. In contrast, entering a dormant state early during a dry down allows microbes to save C by respiring less (due to lowered active biomass), avoid C starvation when substrate diffusion breaks down, and use available C for growth and maintenance rather than osmoregulation. Hence, this strategy explains why little osmolytes are found in microbial biomass subjected to experimental drought. We conclude by highlighting how our results can be implemented in Earth System Models without excessively increasing their complexity.

  10. Chronic physiological increases in cortisol inhibit the vasopressin response to hypertonicity in conscious dogs.

    PubMed

    Papanek, P E; Raff, H

    1994-11-01

    Chronic increases in cortisol inhibit basal plasma arginine vasopressin (AVP). Acute pretreatment with cortisol inhibits the large increase in AVP during hypotension or hypoxia but does not inhibit the modest increase in AVP in response to hypertonic saline (HS). We evaluated the effect of a chronic increase in cortisol (physiological range) on the acute AVP response to HS. Five male dogs received a continuous infusion of either vehicle or cortisol (65 mg/day) for 7 days. The AVP response to HS (0.2 mmol.kg-1.min-1 for 30 min) was tested before infusion, on days 1, 4, and 7 of chronic infusion, and 2 days after the infusion was discontinued. Plasma cortisol increased significantly from 1.0 +/- 0.2 micrograms/dl to an average over the 7 days of infusion of 5.0 +/- 0.2 micrograms/dl, and basal plasma AVP was significantly decreased during cortisol infusion. The increase in plasma Na and osmolality during HS was unaffected by chronic infusion. HS resulted in an increase in AVP from 3.5 +/- 0.2 to 7.1 +/- 0.7 pg/ml before cortisol infusion. After 7 days of cortisol, the AVP response to HS (from 2.6 +/- 0.1 to 3.9 +/- 0.7 pg/ml) was significantly attenuated. Sustained, physiological increases in cortisol significantly inhibited osmotically stimulated AVP release. The decrease in AVP during hypercortisolism and the syndrome of inappropriate antidiuretic hormone in patients with adrenal insufficiency appear to be due to an inhibitory effect of cortisol on the osmotic sensitivity of the AVP control system.

  11. Non-invasive cortisol measurements as indicators of physiological stress responses in guinea pigs

    PubMed Central

    Pschernig, Elisabeth; Wallner, Bernard; Millesi, Eva

    2016-01-01

    Non-invasive measurements of glucocorticoid (GC) concentrations, including cortisol and corticosterone, serve as reliable indicators of adrenocortical activities and physiological stress loads in a variety of species. As an alternative to invasive analyses based on plasma, GC concentrations in saliva still represent single-point-of-time measurements, suitable for studying short-term or acute stress responses, whereas fecal GC metabolites (FGMs) reflect overall stress loads and stress responses after a species-specific time frame in the long-term. In our study species, the domestic guinea pig, GC measurements are commonly used to indicate stress responses to different environmental conditions, but the biological relevance of non-invasive measurements is widely unknown. We therefore established an experimental protocol based on the animals’ natural stress responses to different environmental conditions and compared GC levels in plasma, saliva, and fecal samples during non-stressful social isolations and stressful two-hour social confrontations with unfamiliar individuals. Plasma and saliva cortisol concentrations were significantly increased directly after the social confrontations, and plasma and saliva cortisol levels were strongly correlated. This demonstrates a high biological relevance of GC measurements in saliva. FGM levels measured 20 h afterwards, representing the reported mean gut passage time based on physiological validations, revealed that the overall stress load was not affected by the confrontations, but also no relations to plasma cortisol levels were detected. We therefore measured FGMs in two-hour intervals for 24 h after another social confrontation and detected significantly increased levels after four to twelve hours, reaching peak concentrations already after six hours. Our findings confirm that non-invasive GC measurements in guinea pigs are highly biologically relevant in indicating physiological stress responses compared to circulating

  12. Acute metabolic and physiologic response of goats to narcosis

    NASA Technical Reports Server (NTRS)

    Schatte, C. L.; Bennett, P. B.

    1973-01-01

    Assessment of the metabolic consequences of exposure to elevated partial pressures of nitrogen and helium under normobaric and hyperbaric conditions in goats. The results include the finding that hyperbaric nitrogen causes and increase in metabolic rate and a general decrease in blood constituent levels which is interpreted as reflecting a shift toward fatty acid metabolism at the expense of carbohydrates. A similar but more pronounced pattern was observed with hyperbaric helium.

  13. Parasite Manipulation of Its Host's Physiological Reaction to Acute Stress: Experimental Results from a Natural Beetle-Nematode System.

    PubMed

    Davis, Andrew K; Vasquez, David; LeFeuvre, Jake; Sims, Stuart; Craft, Meghan; Vizurraga, Anna

    All animals, whether vertebrate or invertebrate, must be capable of reacting to acute stressors, such as escaping from predators, and most do so with a suite of transient physiological changes that temporarily enhance survival. Some of these changes include mobilization of immune cells and increased cardiac output. A small but growing number of studies have begun to show that certain parasites appear capable of modifying such responses. We addressed this topic using a natural host and parasite system, that is, a nematode (Chondronema passali) that parasitizes horned passalus beetles, Odontotaenius disjunctus (family Passalidae), of the eastern United States. With a series of experiments, we sought to determine whether this parasite affects (1) the immune reaction to stress, (2) the output of stress-induced alarm calls, or (3) the increase in heart rate that occurs in response to acute stressors, with the stressors being mechanical or thermal. Results showed that hemocyte density increased after both stressors in nonparasitized beetles but did not increase in parasitized beetles. While mobilization of immune cells would enhance host immunity during stress, this would also be damaging to the nematode, so this scenario appears to benefit the parasite. We found no evidence that the nematode suppresses the overall reaction to stress (or prevents stress from occurring), since parasitized beetles did not differ from nonparasitized ones in alarm call rates or in heart beat frequency after exposure to mechanical stressors. Suppression of the host's normal immune reaction to stressful stimuli could translate to delayed or even reduced wound healing or pathogen resistance during these events. This project is a rare demonstration of parasite manipulation of host immune response to acute stress and should stimulate further investigations into the interactive nature of stress and parasites.

  14. Acute hemodynamic responses to weightlessness in humans

    NASA Technical Reports Server (NTRS)

    Lathers, C. M.; Charles, J. B.; Elton, K. F.; Holt, T. A.; Mukai, C.; Bennett, B. S.; Bungo, M. W.

    1989-01-01

    As NASA designs space flights requiring prolonged periods of weightlessness for a broader segment of the population, it will be important to know the acute and sustained effects of weightlessness on the cardiovascular system since this information will contribute to understanding of the clinical pharmacology of drugs administered in space. Due to operational constraints on space flights, earliest effects of weightlessness have not been documented. We examined hemodynamic responses of humans to transitions from acceleration to weightlessness during parabolic flight on NASA's KC-135 aircraft. Impedance cardiography data were collected over four sets of 8-10 parabolas, with a brief rest period between sets. Each parabola included a period of 1.8 Gz, then approximately 20 seconds of weightlessness, and finally a period of 1.6 Gz; the cycle repeated almost immediately for the remainder of the set. Subjects were semi-supine (Shuttle launch posture) for the first set, then randomly supine, sitting and standing for each subsequent set. Transition to weightlessness while standing produced decreased heart rate, increased thoracic fluid content, and increased stroke index. Surprisingly, the onset of weightlessness in the semi-supine posture produced little evidence of a headward fluid shift. Heart rate, stroke index, and cardiac index are virtually unchanged after 20 seconds of weightlessness, and thoracic fluid content is slightly decreased. Semi-supine responses run counter to Shuttle crewmember reports of noticeable fluid shift after minutes to hours in orbit. Apparently, the headward fluid shift commences in the semi-supine posture before launch. is augmented by launch acceleration, but briefly interrupted immediately in orbit, then resumes and is completed over the next hours.

  15. Somatosensory-evoked blink response: investigation of the physiological mechanisms.

    PubMed

    Miwa, H; Nohara, C; Hotta, M; Shimo, Y; Amemiya, K

    1998-02-01

    The somatosensory-evoked blink response (SBR) is a newly identified blink reflex elicited by electrical stimulation of peripheral nerves. The present study was performed to investigate the physiological mechanism underlying the SBR elicited by median nerve stimulation in normal subjects. The peripheral afferents responsible for the SBR included low-threshold cutaneous fibres. In the SBR-positive subjects, the late (R2) component of the blink reflex elicited by supraorbital nerve stimulation and the SBR facilitated each other when both responses were induced at the same time, but they each caused long-lasting inhibition in the other when one stimulus was given as a conditioning stimulus. The extent of inhibition was correlated with the size of the preceding SBR. In the SBR-negative subjects, simultaneous inhibition of R2 was observed when median nerve stimulation was applied as a conditioning stimulus. Brainstem excitability, as evaluated by blink-reflex recovery studies, did not differ between SBR-positive and SBR-negative subjects. Therefore, based on anatomical and physiological findings, it appears that the reflex pathways of the SBR and R2 converge within the brainstem and compete with each other, presumably by presynaptic inhibition at the premotor level, before entering the common blink-reflex pathway. The influence of median nerve stimulation upon tonic contraction of the orbicularis oculi muscle was studied to detect the latent SBR. There was not only a facilitatory period corresponding to the SBR but also an active inhibitory period (exteroceptive suppression), suggesting that the mechanism generating the SBR is not only influenced by blink-reflex volleys but also by active exteroceptive suppression. Thus, the SBR may appear as a result of integration of facilitatory and inhibitory mechanisms within the brainstem.

  16. Proteomic and Physiological Responses of Kineococcus radiotolerans to Copper

    PubMed Central

    Bagwell, Christopher E.; Hixson, Kim K.; Milliken, Charles E.; Lopez-Ferrer, Daniel; Weitz, Karl K.

    2010-01-01

    Copper is a highly reactive, toxic metal; consequently, transport of this metal within the cell is tightly regulated. Intriguingly, the actinobacterium Kineococcus radiotolerans has been shown to not only accumulate soluble copper to high levels within the cytoplasm, but the phenotype also correlated with enhanced cell growth during chronic exposure to ionizing radiation. This study offers a first glimpse into the physiological and proteomic responses of K. radiotolerans to copper at increasing concentration and distinct growth phases. Aerobic growth rates and biomass yields were similar over a range of Cu(II) concentrations (0–1.5 mM) in complex medium. Copper uptake coincided with active cell growth and intracellular accumulation was positively correlated with Cu(II) concentration in the growth medium (R2 = 0.7). Approximately 40% of protein coding ORFs on the K. radiotolerans genome were differentially expressed in response to the copper treatments imposed. Copper accumulation coincided with increased abundance of proteins involved in oxidative stress and defense, DNA stabilization and repair, and protein turnover. Interestingly, the specific activity of superoxide dismutase was repressed by low to moderate concentrations of copper during exponential growth, and activity was unresponsive to perturbation with paraquot. The biochemical response pathways invoked by sub-lethal copper concentrations are exceptionally complex; though integral cellular functions are preserved, in part, through the coordination of defense enzymes, chaperones, antioxidants and protective osmolytes that likely help maintain cellular redox. This study extends our understanding of the ecology and physiology of this unique actinobacterium that could potentially inspire new biotechnologies in metal recovery and sequestration, and environmental restoration. PMID:20865147

  17. Physiological and Pathological Responses to Head Rotations in Toddler Piglets

    PubMed Central

    Ibrahim, Nicole G.; Ralston, Jill; Smith, Colin

    2010-01-01

    Abstract Closed head injury is the leading cause of death in children less than 4 years of age, and is thought to be caused in part by rotational inertial motion of the brain. Injury patterns associated with inertial rotations are not well understood in the pediatric population. To characterize the physiological and pathological responses of the immature brain to inertial forces and their relationship to neurological development, toddler-age (4-week-old) piglets were subjected to a single non-impact head rotation at either low (31.6 ± 4.7 rad/sec2, n = 4) or moderate (61.0 ± 7.5 rad/sec2, n = 6) angular acceleration in the axial direction. Graded outcomes were observed for both physiological and histopathological responses such that increasing angular acceleration and velocity produced more severe responses. Unlike low-acceleration rotations, moderate-acceleration rotations produced marked EEG amplitude suppression immediately post-injury, which remained suppressed for the 6-h survival period. In addition, significantly more severe subarachnoid hemorrhage, ischemia, and axonal injury by β-amyloid precursor protein (β-APP) were observed in moderate-acceleration animals than low-acceleration animals. When compared to infant-age (5-day-old) animals subjected to similar (54.1 ± 9.6 rad/sec2) acceleration rotations, 4-week-old moderate-acceleration animals sustained similar severities of subarachnoid hemorrhage and axonal injury at 6 h post-injury, despite the larger, softer brain in the older piglets. We conclude that the traditional mechanical engineering approach of scaling by brain mass and stiffness cannot explain the vulnerability of the infant brain to acceleration-deceleration movements, compared with the toddler. PMID:20560753

  18. Physiological Response to Membrane Protein Overexpression in E. coli*

    PubMed Central

    Gubellini, Francesca; Verdon, Grégory; Karpowich, Nathan K.; Luff, Jon D.; Boël, Grégory; Gauthier, Nils; Handelman, Samuel K.; Ades, Sarah E.; Hunt, John F.

    2011-01-01

    Overexpression represents a principal bottleneck in structural and functional studies of integral membrane proteins (IMPs). Although E. coli remains the leading organism for convenient and economical protein overexpression, many IMPs exhibit toxicity on induction in this host and give low yields of properly folded protein. Different mechanisms related to membrane biogenesis and IMP folding have been proposed to contribute to these problems, but there is limited understanding of the physical and physiological constraints on IMP overexpression and folding in vivo. Therefore, we used a variety of genetic, genomic, and microscopy techniques to characterize the physiological responses of Escherichia coli MG1655 cells to overexpression of a set of soluble proteins and IMPs, including constructs exhibiting different levels of toxicity and producing different levels of properly folded versus misfolded product on induction. Genetic marker studies coupled with transcriptomic results indicate only minor perturbations in many of the physiological systems implicated in previous studies of IMP biogenesis. Overexpression of either IMPs or soluble proteins tends to block execution of the standard stationary-phase transcriptional program, although these effects are consistently stronger for the IMPs included in our study. However, these perturbations are not an impediment to successful protein overexpression. We present evidence that, at least for the target proteins included in our study, there is no inherent obstacle to IMP overexpression in E. coli at moderate levels suitable for structural studies and that the biochemical and conformational properties of the proteins themselves are the major obstacles to success. Toxicity associated with target protein activity produces selective pressure leading to preferential growth of cells harboring expression-reducing and inactivating mutations, which can produce chemical heterogeneity in the target protein population, potentially

  19. Physiological and behavioural responses of young horses to hot iron branding and microchip implantation.

    PubMed

    Erber, R; Wulf, M; Becker-Birck, M; Kaps, S; Aurich, J E; Möstl, E; Aurich, C

    2012-02-01

    Branding is the traditional and well-established method used to mark horses, but recently microchip transponders for implantation have become available. In this study, behaviour, physiological stress variables and skin temperature in foals were determined in response to hot-iron branding (n=7) and microchip implantation (n=7). Salivary cortisol concentrations increased in response to branding (1.8 ± 0.2 ng/mL) and microchip implantation (1.4 ± 0.1ng/mL), but cortisol release over time did not differ. In response to both manipulations there was a transient increase in heart rate (P<0.001) and heart rate variability (P<0.01). Branding and microchip implantation induced a comparable aversive behaviour (branding, score 3.86 ± 0.85; microchip, score 4.00 ± 0.82). Both techniques thus caused similar physiological and behavioural changes indicative of stress. Acutely, implantation of a microchip was as stressful as branding in foals. Branding caused a necrotising skin burn lasting at least 7 days. Moreover branding, but not microchip implantation (P<0.001), was accompanied by a generalized increase in skin temperature which was comparable to low degree post-burn hypermetabolism in humans.

  20. Molecular and physiological responses of trees to waterlogging stress.

    PubMed

    Kreuzwieser, Jürgen; Rennenberg, Heinz

    2014-10-01

    One major effect of global climate change will be altered precipitation patterns in many regions of the world. This will cause a higher probability of long-term waterlogging in winter/spring and flash floods in summer because of extreme rainfall events. Particularly, trees not adapted at their natural site to such waterlogging stress can be impaired. Despite the enormous economic, ecological and social importance of forest ecosystems, the effect of waterlogging on trees is far less understood than the effect on many crops or the model plant Arabidopsis. There is only a handful of studies available investigating the transcriptome and metabolome of waterlogged trees. Main physiological responses of trees to waterlogging include the stimulation of fermentative pathways and an accelerated glycolytic flux. Many energy-consuming, anabolic processes are slowed down to overcome the energy crisis mediated by waterlogging. A crucial feature of waterlogging tolerance is the steady supply of glycolysis with carbohydrates, particularly in the roots; stress-sensitive trees fail to maintain sufficient carbohydrate availability resulting in the dieback of the stressed tissues. The present review summarizes physiological and molecular features of waterlogging tolerance of trees; the focus is on carbon metabolism in both, leaves and roots of trees.

  1. Physiological and genetic responses of bacteria to osmotic stress.

    PubMed Central

    Csonka, L N

    1989-01-01

    The capacity of organisms to respond to fluctuations in their osmotic environments is an important physiological process that determines their abilities to thrive in a variety of habitats. The primary response of bacteria to exposure to a high osmotic environment is the accumulation of certain solutes, K+, glutamate, trehalose, proline, and glycinebetaine, at concentrations that are proportional to the osmolarity of the medium. The supposed function of these solutes is to maintain the osmolarity of the cytoplasm at a value greater than the osmolarity of the medium and thus provide turgor pressure within the cells. Accumulation of these metabolites is accomplished by de novo synthesis or by uptake from the medium. Production of proteins that mediate accumulation or uptake of these metabolites is under osmotic control. This review is an account of the processes that mediate adaptation of bacteria to changes in their osmotic environment. PMID:2651863

  2. Physiological response to ''pressure-demand'' respirator wear

    SciTech Connect

    Raven, P.B.; Bradley, O.; Rohm-Young, D.; McClure, F.L.; Skaggs, B.

    1982-07-01

    This investigation determined cardiorespiratory responses of subjects with normal lung function and exercise tolerance and compared them with subjects with moderate impairment of lung function and exercise tolerance. The respirator was an air-line full-face mask (MSA-Ultravue) ''pressure-demand'' breathing type equipped with an inspiratory resistance of 85 mmH/sub 2/0 at 85 L/min air flow. This resistance was operable in conjunction with the fixed 25 mmH/sub 2/O inspiratory and expiratory resistance required to pressurize the face piece. Physiologically and subjectively the response of the normal and moderately impaired subjects to respirator wear during rest, 35%, 50% and 80% of their maximal aerobic capacity (VO/sub 2//sub max/) were not different. However, the pressure swings inside the face piece exceeded 24 cm H/sub 2/O and resulted in 50% of the subjects being unable to finish 10 minutes of work at 80% VO/sub 2//sub max/. The greater the ventilatory demand placed upon the respirator due to increasing workload, the more like a ''demand'' system pressure-flow response the ''pressure-demand'' system produced. Hence, the concept of increased protection and reduced inspiratory resistance as a result of pressurizing the facepiece during heavy work is seriously questioned.

  3. Proteomic and Physiological Responses of Kineococcus radiotolerans to Copper

    SciTech Connect

    Bagwell, Christopher E.; Hixson, Kim K.; Milliken, Charles E.; Lopez-Ferrer, Daniel; Weitz, Karl K.

    2010-08-26

    Copper is a highly reactive, toxic metal whose transport into the cell is tightly regulated. Kineococcus radiotolerans was previously shown to specifically accumulate soluble copper in the cytoplasm and cell growth was significantly enhanced by copper during chronic irradiation. This study provides a systematic investigation of copper accumulation, toxicity, and homeostasis in K. radiotolerans through combined physiological experimentation and quantitative shot-gun proteomics. Aerobic growth rates and biomass yields were similar over a range of Cu(II) concentrations, though intracellular metal accumulation was positively correlated with Cu(II) concentration in the growth medium (R2 = 0.7). Global proteomics analysis revealed a significant positive correlation between the total number of response proteins and their abundance with copper concentration and culture age. Approximately 40% of the K. radiotolerans genome was differentially expressed in response to the copper treatments imposed. Copper accumulation coincided with increased abundance of proteins involved in oxidative stress and defense, DNA stabilization and repair, and protein turnover. Concomitant production of antioxidants and protective osmolytes signifies an important adaptation for maintenance of cellular redox; few known metal binding proteins were detected. This study offers a first glimpse into the complexity of coordinated biochemical response pathways in K. radiotolerans invoked by sub-lethal copper concentrations that may be pertinent for new biotechnologies in metal recovery and sequestration, and environmental restoration.

  4. Characterization of the physiological stress response in lingcod

    USGS Publications Warehouse

    Milston, R.H.; Davis, M.W.; Parker, S.J.; Olla, B.L.; Clements, S.; Schreck, C.B.

    2006-01-01

    The goal of this study was to describe the duration and magnitude of the physiological stress response in lingcod Ophiodon elongatus after exposure to brief handling and sublethal air stressors. The response to these stressors was determined during a 24-h recovery period by measuring concentrations of plasma cortisol, lactate, glucose, sodium, and potassium. Lingcod were subjected to brief handling followed by either a 15-min or a 45-min air stressor in the laboratory. After the 15-min stressor, an increase in cortisol or glucose could not be detected until after 5 min of recovery. Peak concentrations were measured after 30 min for cortisol and after 60 min for glucose and lactate. Glucose and lactate had returned to basal levels after 12 h, whereas cortisol did not return to basal levels until after 24 h of recovery. Immediately following a 45-min air stressor, all measured parameters were significantly elevated over levels in prestressor control fish. Cortisol concentrations tended to increase and reached a measured peak after 8 h of recovery, whereas glucose and lactate reached a measured peak after 1 h of recovery. Cortisol and lactate returned to basal levels within 24 h. Glucose, however, remained elevated even after 24 h of recovery. Plasma ions initially increased during the first hour of recovery, and the concentrations then declined to a level below that measured in control fish for the remainder of the 24-h recovery period. In addition, we evaluated the effect of fish size on the stress response. There was no significant difference between the stress response of smaller (41-49-cm [total length] and larger (50-67-cm) lingcod after 45 min air exposure. In general, both the magnitude and duration of the primary and secondary stress responses in lingcod are comparable to those of salmonids. ?? Copyright by the American Fisheries Society 2006.

  5. Regulation of the acute phase and immune responses

    SciTech Connect

    Sehgal, P.B.; Grieninger, G.; Tosato, G.

    1989-01-01

    This book contains the conference entitled Regulation of the acute phase and immune responses: Interleukin-L. Topics covered include: Interferon-B{sub 2}/26kDa Protein, Regulation of acute phase liver gene expression, and Genetics and regulation of expression of IL-6.

  6. Psycho-physiological response in an automatic parachute jump.

    PubMed

    Clemente-Suárez, Vicente Javier; Robles-Pérez, José Juan; Fernández-Lucas, Jesús

    2016-10-11

    Parachute jump is an extreme activity that elicits an intense stress response that affects jumpers' body systems being able to put them at risk. The present research analysed modifications in blood oxygen saturation (BOS), heart rate (HR), cortisol, glucose, lactate, creatine kinase (CK), muscles strength, cortical arousal, autonomic modulation, pistol magazine reload time (PMRT) and state anxiety before and after an automatic open parachute jump in 38 male Spanish soldiers (25.6 ± 5.9 years). A MANOVA with samples as a fixed factor and Effect Size (ES) were conducted. MANOVA showed (Wilks lambda = .225; F = 5.980; P = .000) a significantly increase in cortisol (6.2 ± 3.2 vs. 8.2 ± 4.3 nmol/l; P = .025; ES = .47), HR (75.0 ± 14.6 vs. 87.4 ± 17.3 bpm; P = .004; ES = .72), lactate (1.8 ± 1.2 vs. 4.4 ± 2.2 mmol · l(-1); P = .002; ES = 1.18), sympathetic nervous system and leg strength manifestation after the parachute jump. By contrary BOS, PMRT (55.6 ± 27.6 vs. 48.0 ± 16.7 s; P = .021; ES = .46) and somatic anxiety (SA), evaluated by CSAI2R questionnaire, decreased. An automatic parachute jump increased physiological and cortical response and decreased SA of participants. This stress response can affect the jumpers' abilities and allow us to have a better understanding of the organism stress response and to improve training for both military and sport parachute jumps.

  7. Physiological limitation at alpine treeline: relationships of threshold responses of conifers to their establishment patterns

    NASA Astrophysics Data System (ADS)

    Germino, M. J.; Lazarus, B.; Castanha, C.; Moyes, A. B.; Kueppers, L. M.

    2014-12-01

    An understanding of physiological limitations to tree establishment at alpine treeline form the basis for predicting how this climate-driven boundary will respond to climate shifts. Most research on this topic has focused on limitations related to carbon balance and growth of trees. Carbon balance could limit survival and establishment primarily through slow-acting, chronic means. We asked whether tree survival and thus establishment patterns reflect control by chronic effects in comparison to acute, threshold responses, such as survival of frost events. Seedling survivorship patterns were compared to thresholds in freezing (temperature causing leaf freezing, or freezing point, FP; and physiological response to freezing) and water status (turgor loss point, TLP; and related physiological adjustments). Subject seedlings were from forest, treeline, and alpine sites in the Alpine Treeline Warming Experiment in Colorado, and included limber and lodgepole pine (a low-elevation species), and Engelmann Spruce. Preliminary results show survival increases with seedling age, but the only corresponding increase in stress acclimation was photosynthetic resistance to freezing and TLP, not FP. Differences in survivorship among the species were not consistent with variation in FP but they generally agreed with variation in photosynthetic resistance to deep freezing and to early-season drought avoidance. Mortality of limber pine increased 35% when minimum temperatures decreased below -9C, which compares with FPs of >-8.6C, and about 1/3 of its mortality occurred during cold/wet events, particularly in the alpine. The other major correlate of mortality is midsummer drying events, as previously reported. Also in limber pine, the TLP for year-old seedlings (-2.5 MPa) corresponded with seasonal-drought mortality. In summary, we show several examples of correspondence in physiological thresholds to mortality events within a species, although the relationships are not strong. Across

  8. Effects of acute thermal stress on the survival, predator avoidance, and physiology of juvenile fall Chinook salmon

    USGS Publications Warehouse

    Mesa, M.G.; Weiland, L.K.; Wagner, P.

    2002-01-01

    We subjected juvenile fall chinook salmon from the Hanford Reach of the Columbia River to acute thermal stressors in the laboratory that were derived from field data. We assessed the effects of thermal stress on: (1) the extent of direct mortality; (2) the vulnerability of fish to predation by smallmouth bass; and (3) some general physiological stress responses and synthesis of heat shock protein 70 (hsp70). Thermally-stressed fish showed little direct mortality and no increases in vulnerability to predation. However, these fish showed transient increases in plasma concentrations of cortisol, glucose, and lactate, and a dramatic (25-fold higher than controls) and persistent (lasting 2 wk) increase in levels of liver hsp70. Our results indicate that exposure of Hanford Reach juvenile fall chinook salmon to such stressors did not lead to significant increases in direct mortality or vulnerability to predation, but did alter physiological homeostasis, which should be of concern to those managing this resource. Because our fish received only a single exposure to one of the stressors we examined, we are also concerned about the consequences of exposing fish to multiple, cumulative stressors - a likely scenario for fish in the wild.

  9. Comparison of acute physiology and chronic health evaluation II and acute physiology and chronic health evaluation IV to predict intensive care unit mortality

    PubMed Central

    Parajuli, Bashu Dev; Shrestha, Gentle S.; Pradhan, Bishwas; Amatya, Roshana

    2015-01-01

    Context: Clinical assessment of severity of illness is an essential component of medical practice to predict the outcome of critically ill-patient. Acute Physiology and Chronic Health Evaluation (APACHE) model is one of the widely used scoring systems. Aims: This study was designed to evaluate the Performance of APACHE II and IV scoring systems in our Intensive Care Unit (ICU). Settings and Design: A prospective study in 6 bedded ICU, including 76 patients all above 15 years. Subjects and Methods: APACHE II and APACHE IV scores were calculated based on the worst values in the first 24 h of admission. All enrolled patients were followed, and outcome was recorded as survivors or nonsurvivors. Statistical Analysis Used: SPSS version 17. Results: The mean APACHE score was significantly higher among nonsurvivors than survivors (P < 0.005). Discrimination for APACHE II and APACHE IV was fair with area under receiver operating characteristic curve of 0.73 and 0.79 respectively. The cut-off point with best Youden index for APACHE II was 17 and for APACHE IV was 85. Above cut-off point, mortality was higher for both models (P < 0.005). Hosmer–Lemeshow Chi-square coefficient test showed better calibration for APACHE II than APACHE IV. A positive correlation was seen between the models with Spearman's correlation coefficient of 0.748 (P < 0.01). Conclusions: Discrimination was better for APACHE IV than APACHE II model however Calibration was better for APACHE II than APACHE IV model in our study. There was good correlation between the two models observed in our study. PMID:25722550

  10. Ethephon induced abscission in mango: physiological fruitlet responses

    PubMed Central

    Hagemann, Michael H.; Winterhagen, Patrick; Hegele, Martin; Wünsche, Jens N.

    2015-01-01

    Fruitlet abscission of mango is typically very severe, causing considerable production losses worldwide. Consequently, a detailed physiological and molecular characterization of fruitlet abscission in mango is required to describe the onset and time-dependent course of this process. To identify the underlying key mechanisms of abscission, ethephon, an ethylene releasing substance, was applied at two concentrations (600 and 7200 ppm) during the midseason drop stage of mango. The abscission process is triggered by ethylene diffusing to the abscission zone where it binds to specific receptors and thereby activating several key physiological responses at the cellular level. The treatments reduced significantly the capacity of polar auxin transport through the pedicel at 1 day after treatment and thereafter when compared to untreated pedicels. The transcript levels of the ethylene receptor genes MiETR1 and MiERS1 were significantly upregulated in the pedicel and pericarp at 1, 2, and 3 days after the ethephon application with 7200 ppm, except for MiETR1 in the pedicel, when compared to untreated fruitlet. In contrast, ethephon applications with 600 ppm did not affect expression levels of MiETR1 in the pedicel and of MiERS1 in the pericarp; however, MiETR1 in the pericarp at day 2 and MiERS1 in the pedicel at days 2 and 3 were significantly upregulated over the controls. Moreover, two novel short versions of the MiERS1 were identified and detected more often in the pedicel of treated than untreated fruitlets at all sampling times. Sucrose concentration in the fruitlet pericarp was significantly reduced to the control at 2 days after both ethephon treatments. In conclusion, it is postulated that the ethephon-induced abscission process commences with a reduction of the polar auxin transport capacity in the pedicel, followed by an upregulation of ethylene receptors and finally a decrease of the sucrose concentration in the fruitlets. PMID:26442021

  11. Physiological and perceptual responses to Latin partnered social dance.

    PubMed

    Domene, Pablo A; Moir, Hannah J; Pummell, Elizabeth; Easton, Chris

    2014-10-01

    The purpose of this study was to investigate the physiological and perceptual responses to Latin partnered social dance to salsa music when performed as a self-selected activity within an ecologically valid setting. Eighteen non-professional adult Latin dancers undertook a laboratory-based graded exercise test for determination of maximal oxygen uptake and maximal heart rate. The dancers then attended two Latin partnered social dance sessions in established salsa venues in London, UK over a 2 wk period. Physiological data were collected using a wrist-worn ActiGraph wGT3X+ accelerometer with accompanying heart rate monitor. Perceived benefits of dance were assessed via the Exercise Benefits/Barriers Scale, and measurement of state intrinsic motivation during dance was undertaken using the Intrinsic Motivation Inventory. Total step count during 2h of dance was not different (t16 = -.39, p = .71) between females and males (9643 ± 1735 step); however, women expended a significantly lower (t16 = -2.57, p < .05) total energy expenditure when compared to men (479 ± 125 versus 651 ± 159 kcal). Dancers of both genders considered interest-enjoyment to be the motivator of primary importance. The highest rated perceived benefit of dance was psychological outlook. Latin partnered social dance to salsa music demands moderate to vigorous physical activity intensity levels, and further, fosters interest, enjoyment, and a positive psychological outlook among novice to advanced adult Latin dancers taking part primarily for leisure purposes. These findings may be of use for those interested in the efficacy of Latin social dancing as an expressive medium for the promotion of community health.

  12. Inhalation of diethylamine--acute nasal effects and subjective response

    SciTech Connect

    Lundqvist, G.R.; Yamagiwa, M.; Pedersen, O.F.; Nielsen, G.D. )

    1992-03-01

    Adult volunteers were exposed to 25 ppm (75 mg/m3) diethylamine in a climate chamber for 15 min in order to study the acute nasal reactions to an exposure equivalent to the present threshold limit value-short-term exposure limit. Changes in nasal volume and nasal resistance were measured by acoustic rhinometry and by rhinomanometry. Acute change in nasal volume, usually seen as acute nasal mucosa response to thermal stimuli, was not observed, nor was an acute change in nasal airway resistance. In a subsequent experiment, the aim was to measure acute sensory effects. Exposure to a concentration increasing from 0 to 12 ppm took place for 60 min, equal to an average concentration of 10 ppm (30 mg/m3). A moderate to strong olfactory response and distinct nasal and eye irritation were observed. In spite of considerable individual variation, the results were in agreement with sensory effect estimates obtained from animal studies.

  13. Rapid cooling after acute hyperthermia alters intestinal tissue morphology and increases the systemic inflammatory response in pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Acute hyperthermia can result in mortality if recovery is not appropriately managed. The study objective was to determine the effects of heatstroke recovery methods on the physiological response in pigs. In four repetitions, 36 male pigs (88.7 ± 1.6 kg BW) were exposed to thermoneutral conditions (T...

  14. Physiological and proteomic responses to single and repeated hypoxia in juvenile Eurasian perch under domestication--clues to physiological acclimation and humoral immune modulations.

    PubMed

    Douxfils, Jessica; Deprez, Mélissa; Mandiki, S N M; Milla, Sylvain; Henrotte, Emilie; Mathieu, Cédric; Silvestre, Frédéric; Vandecan, Michaël; Rougeot, Carole; Mélard, Charles; Dieu, Marc; Raes, Martine; Kestemont, Patrick

    2012-11-01

    We evaluated the physiological and humoral immune responses of Eurasian perch submitted to 4-h hypoxia in either single or repeated way. Two generations (F1 and F5) were tested to study the potential changes in these responses with domestication. In both generations, single and repeated hypoxia resulted in hyperglycemia and spleen somatic index reduction. Glucose elevation and lysozyme activity decreased following repeated hypoxia. Complement hemolytic activity was unchanged regardless of hypoxic stress or domestication level. A 2D-DIGE proteomic analysis showed that some C3 components were positively modulated by single hypoxia while C3 up- and down-regulations and over-expression of transferrin were observed following repeated hypoxia. Domestication was associated with a low divergence in stress and immune responses to hypoxia but was accompanied by various changes in the abundance of serum proteins related to innate/specific immunity and acute phase response. Thus, it appeared that the humoral immune system was modulated following single and repeated hypoxia (independently of generational level) or during domestication and that Eurasian perch may display physiological acclimation to frequent hypoxic disturbances.

  15. Melatonin modulates the fetal cardiovascular defense response to acute hypoxia

    PubMed Central

    Thakor, Avnesh S; Allison, Beth J; Niu, Youguo; Botting, Kimberley J; Serón-Ferré, Maria; Herrera, Emilio A; Giussani, Dino A

    2015-01-01

    Experimental studies in animal models supporting protective effects on the fetus of melatonin in adverse pregnancy have prompted clinical trials in human pregnancy complicated by fetal growth restriction. However, the effects of melatonin on the fetal defense to acute hypoxia, such as that which may occur during labor, remain unknown. This translational study tested the hypothesis, in vivo, that melatonin modulates the fetal cardiometabolic defense responses to acute hypoxia in chronically instrumented late gestation fetal sheep via alterations in fetal nitric oxide (NO) bioavailability. Under anesthesia, 6 fetal sheep at 0.85 gestation were instrumented with vascular catheters and a Transonic flow probe around a femoral artery. Five days later, fetuses were exposed to acute hypoxia with or without melatonin treatment. Fetal blood was taken to determine blood gas and metabolic status and plasma catecholamine concentrations. Hypoxia during melatonin treatment was repeated during in vivo NO blockade with the NO clamp. This technique permits blockade of de novo synthesis of NO while compensating for the tonic production of the gas, thereby maintaining basal cardiovascular function. Melatonin suppressed the redistribution of blood flow away from peripheral circulations and the glycemic and plasma catecholamine responses to acute hypoxia. These are important components of the fetal brain sparing response to acute hypoxia. The effects of melatonin involved NO-dependent mechanisms as the responses were reverted by fetal treatment with the NO clamp. Melatonin modulates the in vivo fetal cardiometabolic responses to acute hypoxia by increasing NO bioavailability. PMID:25908097

  16. Setting safe acute exposure limits for halon replacement chemicals using physiologically based pharmacokinetic modeling.

    PubMed

    Vinegar, A; Jepson, G W; Cisneros, M; Rubenstein, R; Brock, W J

    2000-08-01

    Most proposed replacements for Halon 1301 as a fire suppressant are halogenated hydrocarbons. The acute toxic endpoint of concern for these agents is cardiac sensitization. An approach is described that links the cardiac endpoint as assessed in dogs to a target arterial concentration in humans. Linkage was made using a physiologically based pharmacokinetic (PBPK) model. Monte Carlo simulations, which account for population variability, were used to establish safe exposure times at different exposure concentrations for Halon 1301 (bromotrifluoromethane), CF(3)I (trifluoroiodomethane), HFC-125 (pentafluoroethane), HFC-227ea (1,1,1,2,3,3,3-heptafluoropropane), and HFC-236fa (1,1,1,3,3,3-hexafluoropropane). Application of the modeling technique described here not only makes use of the conservative cardiac sensitization endpoint, but also uses an understanding of the pharmacokinetics of the chemical agents to better establish standards for safe exposure. The combined application of cardiac sensitization data and physiologically based modeling provides a quantitative approach, which can facilitate the selection and effective use of halon replacement candidates.

  17. Physiological and behavioral responses of sheep to gaseous ammonia.

    PubMed

    Phillips, C J C; Pines, M K; Latter, M; Muller, T; Petherick, J C; Norman, S T; Gaughan, J B

    2012-05-01

    Ammonia can accumulate in highly stocked sheep accommodation, for example during live export shipments, and could affect sheep health and welfare. Thus, the objective of this experiment was to test the effects of 4 NH(3) concentrations, 4 (control), 12, 21, and 34 mg/m(3), on the physiology and behavior of wether sheep. Sheep were held for 12 d under a micro-climate and stocking density similar to shipboard conditions recorded on voyages from Australia to the Middle East during the northern hemispheric summer. Ammonia increased macrophage activity in transtracheal aspirations, indicating active pulmonary inflammation; however, it had no effect (P > 0.05) on hematological variables. Feed intake decreased (P = 0.002) in proportion to ammonia concentration, and BW gain decreased (P < 0.001) at the 2 greatest concentrations. Exposure to ammonia increased (P = 0.03) the frequency of sneezing, and at the greatest ammonia concentration, sheep were less active, with less locomotion, pawing, and panting. Twenty-eight days after exposure to NH(3), the pulmonary macrophage activity and BW of the sheep returned to that of sheep exposed to only 4 mg/m(3). It was concluded that NH(3) induced a temporary inflammatory response of the respiratory system and reduced BW gain, which together indicated a transitory adverse effect on the welfare of sheep.

  18. Physiological responses in potato plants under continuous irradiation

    NASA Technical Reports Server (NTRS)

    Cao, W.; Tibbitts, T. W.

    1991-01-01

    The physiological responses of four potato (Solanum tuberosum L.) cultivars to continuous irradiation were determined in a controlled environment. Under a constant 18C and a constant photoperiod of 470 micromoles s-1 m-2 of photosynthetic photon flux, 'Denali' and 'Haig' grew well and produced large plant and tuber dry weights when harvested 56 days after transplanting. 'Kennebec' and 'Superior' were severely stunted, producing only 10% of the plant dry matter produced by 'Denali' and 'Haig'. The differences in leaf chlorophyll concentration and stomatal conductance were not consistent between these two groups of cultivars. The leaf net CO2 assimilation rates in 'Kennebec' and 'Superior' were lower, and intercellular CO2 partial pressures were higher than in 'Denali' and 'Haig'. These results indicate that inhibition of net CO2 assimilation in 'Kennebec' and 'Superior' was not due to a limiting amount of chlorophyll or to CO2 in the leaf tissues. Concentrations of starch in leaflets of 'Kennebec' and 'Superior' plants were only 10% of those in 'Denali' and 'Haig' plants, although soluble sugar concentrations were similar in the four cultivars. Therefore, the lower net CO2 assimilation rates in stunted 'Kennebec' and 'Superior' plants were not associated with an excess carbohydrate accumulation in the leaves.

  19. Physiological response to submaximal isometric contractions of the paravertebral muscles

    NASA Technical Reports Server (NTRS)

    Jensen, B. R.; Jorgensen, K.; Hargens, A. R.; Nielsen, P. K.; Nicolaisen, T.

    1999-01-01

    STUDY DESIGN: Brief (30-second) isometric trunk extensions at 5%, 20%, 40%, 60%, and 80% of maximal voluntary contraction (MVC) and 3 minutes of prolonged trunk extension (20% MVC) in erect position were studied in nine healthy male subjects. OBJECTIVES: To investigate the intercorrelation between intramuscular pressure and tissue oxygenation of the paravertebral muscles during submaximal isometric contractions and further, to evaluate paravertebral electromyogram and intramuscular pressure as indicators of force development. SUMMARY OF BACKGROUND DATA: Local physiologic responses to muscle contraction are incompletely understood. METHODS: Relative oxygenation was monitored with noninvasive near-infrared spectroscopy, intramuscular pressure was measured with a transducer-tipped catheter, and surface electromyogram was monitored at three recording sites. RESULTS: The root mean square amplitudes of the paravertebral electromyogram (L4, left and right; T12, right) and intramuscular pressure measured in the lumbar multifidus muscle at L4 increased with greater force development in a curvilinear manner. A significant decrease in the oxygenation of the lumbar paravertebral muscle in response to muscle contraction was found at an initial contraction level of 20% MVC. This corresponded to a paravertebral intramuscular pressure of 30-40 mm Hg. However, during prolonged trunk extension, no further decrease in tissue oxygenation was found compared with the tissue oxygenation level at the end of the brief contractions, indicating that homeostatic adjustments (mean blood pressure and heart rate) over time were sufficient to maintain paravertebral muscle oxygen levels. CONCLUSION: At a threshold intramuscular pressure of 30-40 mm Hg during muscle contraction, oxygenation in the paravertebral muscles is significantly reduced. The effect of further increase in intramuscular pressure on tissue oxygenation over time may be compensated for by an increase in blood pressure and heart

  20. Human thermal physiological and psychological responses under different heating environments.

    PubMed

    Wang, Zhaojun; Ning, Haoran; Ji, Yuchen; Hou, Juan; He, Yanan

    2015-08-01

    Anecdotal evidence suggests that many residents of severely cold areas of China who use floor heating (FH) systems feel warmer but drier compared to those using radiant heating (RH) systems. However, this phenomenon has not been verified experimentally. In order to validate the empirical hypothesis, and research the differences of human physiological and psychological responses in these two asymmetrical heating environments, an experiment was designed to mimic FH and RH systems. The subjects participating in the experiment were volunteer college-students. During the experiment, the indoor air temperature, air speed, relative humidity, globe temperature, and inner surface temperatures were measured, and subjects' heart rate, blood pressure and skin temperatures were recorded. The subjects were required to fill in questionnaires about their thermal responses during testing. The results showed that the subjects' skin temperatures, heart rate and blood pressure were significantly affected by the type of heating environment. Ankle temperature had greatest impact on overall thermal comfort relative to other body parts, and a slightly cool FH condition was the most pleasurable environment for sedentary subjects. The overall thermal sensation, comfort and acceptability of FH were higher than that of RH. However, the subjects of FH felt drier than that of RH, although the relative humidity in FH environments was higher than that of the RH environment. In future environmental design, the thermal comfort of the ankles should be scrutinized, and a FH cool condition is recommended as the most comfortable thermal environment for office workers. Consequently, large amounts of heating energy could be saved in this area in the winter. The results of this study may lead to more efficient energy use for office or home heating systems.

  1. Physiologic Responses Produced by Active and Passive Personal Cooling Vests

    NASA Technical Reports Server (NTRS)

    Ku, Yu-Tsuan E.; Lee, Hank C.; Montgomery, Leslie D.; Luna, Bernadette

    2000-01-01

    Personal thermoregulatory systems which provide chest cooling are used in the industrial and aerospace environments to alleviate thermal stress. However, little information is available regarding the physiologic and circulatory changes produced by routine operation of these systems. The objectives of this study were to document and compare the subjects' response to three cooling vests in their recommended configurations. The Life Enhancement Tech (LET) lightweight active cooling vest with cap, the MicroClimate Systems Change of Phase garment (MCS), and the Steele Vest were each used to cool the chest regions of 12 male and 8 female Healthy subjects (21 to 69 yr.) in this study. The subjects, seated in an upright position at normal room temperature (approx. 22 C), were tested for 60 min. with one of the cooling garments. The LET active garment had an initial coolant fluid inlet temperature of 60 F, and was ramped down to 50 F. Oral, right and left ear canal temperatures were logged manually every 5 min. Arm, leg, chest and rectal temperatures; heart rate; and respiration were recorded continuously on a U.F.I., Inc. Biolog ambulatory monitor. For men, all three vests had similar, significant cooling effects. Decreases in the average rectal temperature, oral temperature, and ear canal temperatures were approximately 0.2 C, 0.2 C and 0.1 C, respectively. In contrast to the men, the female subjects wearing the MCS and Steel vests had similar cooling responses in which the core temperature remained elevated and oral and ear canal temperatures did not drop. The LET active garment cooled most of the female subjects in this study; rectal, oral and ear temperature decreased about 0.2 C, 0.3 C and 0.3 C, respectively. These results show that the garment configurations tested do not elicit a similar thermal response in all subjects. A gender difference is evident. The LET active garment configuration was most effective in decreasing temperatures of the female subjects; the MCS

  2. Physiological responses to environmental factors related to space flight

    NASA Technical Reports Server (NTRS)

    Pace, N.

    1972-01-01

    The research is reported for establishing physiological base line data, and for developing procedures and instrumentation necessary for the automatic measurement of hemodynamic and metabolic parameters. The work in the following areas is discussed: biochemistry, bioinstrumentation, nutrition, physiology, experimental surgery, and animal colony.

  3. Artificial light at night alters delayed-type hypersensitivity reaction in response to acute stress in Siberian hamsters.

    PubMed

    Bedrosian, Tracy A; Aubrecht, Taryn G; Kaugars, Katherine E; Weil, Zachary M; Nelson, Randy J

    2013-11-01

    Several physiological and behavioral processes rely on precisely timed light information derived from the natural solar cycle. Using this information, traits have adapted to allow individuals within specific niches to optimize survival and reproduction, but urbanization by humans has significantly altered natural habitats. Nighttime light exposure alters immune function in several species, which could lead to decreased fitness or survival, particularly in the face of an environmental challenge. We exposed male Siberian hamsters (Phodopus sungorus) to five lux of light at night for four weeks, and then administered six hours of acute restraint stress. Delayed-type hypersensitivity (DTH) response was assessed immediately following stress. Acute restraint increased the DTH reaction in dark nights, but exposure to nighttime light prevented this response. Exposure to light at night prolonged the DTH response in non-stressed control hamsters. These results suggest that light pollution may significantly alter physiological responses in Siberian hamsters, particularly in response to a salient environmental challenge such as stress.

  4. Selected human physiological responses during extreme heat: the Badwater Ultramarathon.

    PubMed

    Brown, Jacqueline S; Connolly, Declan A

    2015-06-01

    The purpose of this article was to examine various physiological responses during an ultramarathon held in extreme heat. Our investigation was conducted at The Badwater Ultramarathon, a nonstop 217-km run across Death Valley, CA, USA. This study recruited 4 male athletes, average age of 43 (±SD) (±7.35), (range) 39-54 years. All 4 subjects successfully completed the race with a mean finish time of 36:20:23 hours (±SD) (±3:08:38) (range) 34:05:25-40:51:46 hours, and a mean running speed of 6.03 km·h(-1) (±SD) (±0.05), (range) 5.3-6.4 km·h(-1). The anthropometric variables measured were (mean, ±SD) mass 79.33 kg (±6.43), height 1.80 m (±0.09), body surface area 1.93 m2 (±0.16), body mass index 24.38 kg·m(-2) (±1.25), fat mass 13.88% (±2.29), and body water 62.08% (±1.56). Selected physiological variables measured were core body temperature, skin temperature, heart rate, breathing rate, and blood pressure. Rate of perceived intensity, rate of thermal sensation, and environmental factors were also monitored. Our study found (mean and ±SD) core body temperature 37.49° C (±0.88); skin temperature 31.13° C (±3.06); heart rate 106.79 b·min(-1) (±5.11); breathing rate 36.55 b·min(-1) (±0.60); blood pressure 128/86 mm Hg (±9.24/4.62); rate of perceived intensity 5.49 (±1.26); rate of thermal sensation 4.69 (±0.37); daytime high temperature of 46.6° C, and a mean temperature of 28.35° C. Our fastest finisher demonstrated a lower overall core body temperature (36.91° C) when compared with the group mean (37.49° C). In contrast to previous findings, our data show that the fastest finisher demonstrates a lower overall core body temperature. We conclude that it may be possible that a time threshold exists whereby success in longer duration events requires an ability to maintain a lower core body temperature vs. tolerating a higher core body temperature.

  5. The Circulatory and Metabolic Responses to Hypoxia in Humans – With Special Reference to Adipose Tissue Physiology and Obesity

    PubMed Central

    Heinonen, Ilkka H. A.; Boushel, Robert; Kalliokoski, Kari K.

    2016-01-01

    Adipose tissue metabolism and circulation play an important role in human health. It is well-known that adipose tissue mass is increased in response to excess caloric intake leading to obesity and further to local hypoxia and inflammatory signaling. Acute exercise increases blood supply to adipose tissue and mobilization of fat stores for energy. However, acute exercise during systemic hypoxia reduces subcutaneous blood flow in healthy young subjects, but the response in overweight or obese subjects remains to be investigated. Emerging evidence also indicates that exercise training during hypoxic exposure may provide additive benefits with respect to many traditional cardiovascular risk factors as compared to exercise performed in normoxia, but unfavorable effects of hypoxia have also been documented. These topics will be covered in this brief review dealing with hypoxia and adipose tissue physiology. PMID:27621722

  6. Physiological and behavioral responses of horses during police training.

    PubMed

    Munsters, C C B M; Visser, E K; van den Broek, J; Sloet van Oldruitenborgh-Oosterbaan, M M

    2013-05-01

    Mounted police horses have to cope with challenging, unpredictable situations when on duty and it is essential to gain insight into how these horses handle stress to warrant their welfare. The aim of the study was to evaluate physiological and behavioral responses of 12 (six experienced and six inexperienced) police horses during police training. Horses were evaluated during four test settings at three time points over a 7-week period: outdoor track test, street track test, indoor arena test and smoke machine test. Heart rate (HR; beats/min), HR variability (HRV; root means square of successive differences; ms), behavior score (BS; scores 0 to 5) and standard police performance score (PPS; scores 1 to 0) were obtained per test. All data were statistically evaluated using a linear mixed model (Akaike's Information criterium; t > 2.00) or logistic regression (P < 0.05). HR of horses was increased at indoor arena test (98 ± 26) and smoke machine test (107 ± 25) compared with outdoor track (80 ± 12, t = 2.83 and t = 3.91, respectively) and street track tests (81 ± 14, t = 2.48 and t = 3.52, respectively). HRV of horses at the indoor arena test (42.4 ± 50.2) was significantly lower compared with street track test (85.7 ± 94.3 and t = 2.78). BS did not show significant differences between tests and HR of horses was not always correlated with the observed moderate behavioral responses. HR, HRV, PPS and BS did not differ between repetition of tests and there were no significant differences in any of the four tests between experienced and inexperienced horses. No habituation occurred during the test weeks, and experience as a police horse does not seem to be a key factor in how these horses handle stress. All horses showed only modest behavioral responses, and HR may provide complimentary information for individual evaluation and welfare assessment of these horses. Overall, little evidence of stress was observed during these police training tests. As three of these

  7. Physiological and molecular responses of juvenile shortnose sturgeon (Acipenser brevirostrum) to thermal stress.

    PubMed

    Zhang, Yueyang; Loughery, Jennifer R; Martyniuk, Christopher J; Kieffer, James D

    2017-01-01

    The shortnose sturgeon (Acipenser brevirostrum LeSueur, 1818) is a vulnerable species that is found along the eastern coast of North America. Little is known about temperature tolerance in this species and with a rapidly changing global climate, it becomes increasingly important to define the thermal tolerance of this species to better predict population distribution. Using a modified critical thermal maximum test (CTMax), the objectives of this study were to determine the impact of heating rate (0.1, 0.2 and 0.25°Cmin(-1)) on the thermal tolerance, associated hematological responses, and oxygen consumption in juvenile sturgeon. In addition, transcripts associated with physiological stress and heat shock (i.e., heat shock proteins) were also measured. Heating rate did not alter the CTMax values of shortnose sturgeon. Neither heating rate nor thermal stress affected plasma sodium and chloride levels, nor the expression of transcripts that included catalase, glucocorticoid receptor, heat shock protein70 (hsp70), heat shock protein 90α (hsp90α) and cytochrome P450 1a (cyp1a). However, regardless of heating rate, thermal stress increased both plasma potassium and lactate concentrations. Glucose levels were increased at heating rates of 0.2 and 0.25°Cmin(-1), but not at 0.1°Cmin(-1). Overall, oxygen consumption rates increased with thermal stress, but the response patterns were not affected by heating rate. These data support the hypothesis that shortnose sturgeon can tolerate acute heat stress, as many physiological and molecular parameters measured here were non-responsive to the thermal stress.

  8. Physiological responses of Matricaria chamomilla to cadmium and copper excess.

    PubMed

    Kovácik, Jozef; Backor, Martin; Kaduková, Jana

    2008-02-01

    Physiological responses of Matricaria chamomilla plants exposed to cadmium (Cd) and copper (Cu) excess (3, 60, and 120 microM for 7 days) with special emphasis on phenolic metabolism were studied. Cu at 120 microM reduced chamomile growth, especially in the roots where it was more abundant than Cd. Notwithstanding the low leaf Cu amount (37.5 microg g(-1) DW) in comparison with Cd (237.8 microg g(-1) DW) at 120 microM, it caused reduction of biomass accumulation, F(v)/F(m) ratio and soluble proteins. In combination with high accumulation of phenolics, strong reduction of proteins and high GPX activity in the roots, this supports severe redox Cu properties. In terms of leaf phenylalanine ammonia-lyase (PAL) activity, it seems that Cd had a stimulatory effect during the course of the experiment, whereas Cu was found to stimulate it after 7-day exposure. The opposite trend was visible in the roots, where Cd had a stimulatory effect at high doses but Cu mainly at the highest dose. This supports the assumption of different PAL time dynamics under Cd and Cu excess. A dose of 60 and 120 microM Cu led to 2- and 3-times higher root lignin accumulation while the same Cd doses increased it by 33 and 68%, respectively. A Cu dose of 120 microM can be considered as limiting for chamomile growth under conditions of present research, while resistance to high Cd doses was confirmed. However, PAL and phenolics seemed to play an important role in detoxification of Cd- and Cu-induced oxidative stress.

  9. Physiological and psychological responses to outdoor vs. laboratory cycling.

    PubMed

    Mieras, Molly E; Heesch, Matthew W S; Slivka, Dustin R

    2014-08-01

    The purpose of this study was to determine the physiological and psychological responses to laboratory vs. outdoor cycling. Twelve recreationally trained male cyclists participated in an initial descriptive testing session and 2 experimental trials consisting of 1 laboratory and 1 outdoor session, in a randomized order. Participants were given a standardized statement instructing them to give the same perceived effort for both the laboratory and outdoor 40-km trials. Variables measured include power output, heart rate (HR), core temperature, skin temperature, body weight, urine specific gravity (USG), Rating of Perceived Exertion (RPE), attentional focus, and environmental conditions. Wind speed was higher in the outdoor trial than in the laboratory trial (2.5 ± 0.6 vs. 0.0 ± 0.0 m·s-1, p = 0.02) whereas all other environmental conditions were similar. Power output (208.1 ± 10.2 vs. 163.4 ± 11.8 W, respectively, p < 0.001) and HR (152 ± 4 and 143 ± 6 b·min-1, respectively, p = 0.04) were higher in the outdoor trial than in the laboratory trial. Core temperature was similar, whereas skin temperature was cooler during the outdoor trial than during the laboratory trial (31.4 ± 0.3 vs. 33.0 ± 0.2° C, respectively, p < 0.001), thus creating a larger thermal gradient between the core and skin outdoors. No significant differences in body weight, USG, RPE, or attentional focus were observed between trials. These data indicate that outdoor cycling allows cyclists to exercise at a higher intensity than in laboratory cycling, despite similar environmental conditions and perceived exertion. In light of this, cyclists may want to ride at a higher perceived exertion in indoor settings to acquire the same benefit as they would from an outdoor ride.

  10. Resistance Training: Physiological Responses and Adaptations (Part 2 of 4).

    ERIC Educational Resources Information Center

    Fleck, Stephen J.; Kraerner, William J.

    1988-01-01

    Resistance training causes a variety of physiological reactions, including changes in muscle size, connective tissue size, and bone mineral content. This article summarizes data from a variety of studies and research. (JL)

  11. Physiological calf responses to increased chromium supply in summer.

    PubMed

    Yari, M; Nikkhah, A; Alikhani, M; Khorvash, M; Rahmani, H; Ghorbani, G R

    2010-09-01

    The primary objective was to determine pre- and postweaning calf physiological responses to increased Cr supply under high ambient temperatures. In a randomized complete block design, 24 neonate Holstein calves (BW=41.5+/-1.9 kg) were grouped based on sex and randomly assigned to 3 treatments within each group. Treatments included either no supplemental Cr (control), 0.02 mg of supplemental Cr/kg of BW0.75, or 0.04 mg of supplemental Cr/kg of BW0.75. The average temperature-humidity index was 77 during the study. Chromium was provided as a commercial product in whole milk for preweaning calves and in a starter concentrate for postweaning calves. Calves were weaned at 1 kg of daily calf starter intake lasting for 6 consecutive days. A glucose tolerance test was conducted on d 25 postweaning. Treatments had no effects on preweaning dry matter intake, feed conversion ratio, average daily gain, and weaning age. Chromium decreased dry matter intake in postweaning calves; however, it did not affect growth and feed conversion ratio. Chromium lowered respiration rate at wk 5 without affecting fecal score and rectal temperature. Preweaning serum cortisol concentrations were altered by a 3-way interaction of Cr dose with calf sex and age. Preweaning serum glucose showed week-dependent increases by Cr. Serum insulin, urea, albumin, total protein, triiodothyronine, and thyroxin concentrations through weaning were not affected. The increasing Cr doses caused quadratic declines in serum thyroxin on d 21 postweaning, whereas blood triiodothyronine declined only with the higher Cr dose. Serum NEFA remained unchanged, but BHBA decreased by Cr in male calves on d 21 postweaning. The glucose tolerance test revealed linear reductions in area under insulin curve between 0 to 90 and 0 to 120 min after glucose infusion, suggesting improvements in peripheral insulin efficiency. Sex-dependent responses to Cr were observed for serum total protein and albumin concentrations at 21 d

  12. Physiological responses to dyadic interactions are influenced by neurotypical adults' levels of autistic and empathy traits.

    PubMed

    Truzzi, Anna; Setoh, Peipei; Shinohara, Kazuyuki; Esposito, Gianluca

    2016-10-15

    Autistic traits are distributed on a continuum that ranges from non-clinical to clinical condition. Atypical responses to social situations represent a core feature of the Autism Spectrum Disorders phenotype. Here, we hypothesize that atypical physiological responses to social stimuli may predict non-clinical autistic and empathy traits levels. We measured physiological responses (heart rate, facial temperature) of 40 adults (20F) while showing them 24 movies representing dyadic interactions. Autistic traits were assessed through Autism Quotient questionnaire (AQ), while empathy traits were measured using the Empathy Quotient questionnaire (EQ). Opposite correlations between AQ and EQ scores and physiological responses were found. Analysis of physiological responses revealed that individuals with better social abilities, low AQ and high EQ, show opposite activation patterns compared to people with high AQ and low EQ. Findings show that physiological responses could be biomarkers for people's autistic traits and social abilities.

  13. Physiological and isotopic responses of scleractinian corals to ocean acidification

    NASA Astrophysics Data System (ADS)

    Krief, Shani; Hendy, Erica J.; Fine, Maoz; Yam, Ruth; Meibom, Anders; Foster, Gavin L.; Shemesh, Aldo

    2010-09-01

    Uptake of anthropogenic CO 2 by the oceans is altering seawater chemistry with potentially serious consequences for coral reef ecosystems due to the reduction of seawater pH and aragonite saturation state ( Ωarag). The objectives of this long-term study were to investigate the viability of two ecologically important reef-building coral species, massive Porites sp. and Stylophora pistillata, exposed to high pCO 2 (or low pH) conditions and to observe possible changes in physiologically related parameters as well as skeletal isotopic composition. Fragments of Porites sp. and S. pistillata were kept for 6-14 months under controlled aquarium conditions characterized by normal and elevated pCO 2 conditions, corresponding to pH T values of 8.09, 7.49, and 7.19, respectively. In contrast with shorter, and therefore more transient experiments, the long experimental timescale achieved in this study ensures complete equilibration and steady state with the experimental environment and guarantees that the data provide insights into viable and stably growing corals. During the experiments, all coral fragments survived and added new skeleton, even at seawater Ωarag < 1, implying that the coral skeleton is formed by mechanisms under strong biological control. Measurements of boron (B), carbon (C), and oxygen (O) isotopic composition of skeleton, C isotopic composition of coral tissue and symbiont zooxanthellae, along with physiological data (such as skeletal growth, tissue biomass, zooxanthellae cell density, and chlorophyll concentration) allow for a direct comparison with corals living under normal conditions and sampled simultaneously. Skeletal growth and zooxanthellae density were found to decrease, whereas coral tissue biomass (measured as protein concentration) and zooxanthellae chlorophyll concentrations increased under high pCO 2 (low pH) conditions. Both species showed similar trends of δ 11B depletion and δ 18O enrichment under reduced pH, whereas the δ 13C results

  14. Rapid Acute Physiology Score versus Rapid Emergency Medicine Score in Trauma Outcome Prediction; a Comparative Study

    PubMed Central

    Nakhjavan-Shahraki, Babak; Baikpour, Masoud; Yousefifard, Mahmoud; Nikseresht, Zahra Sadat; Abiri, Samaneh; Mirzay Razaz, Jalaledin; Faridaalaee, Gholamreza; Pouraghae, Mahboob; Shirzadegan, Sahar; Hosseini, Mostafa

    2017-01-01

    Introduction: Rapid acute physiology score (RAPS) and rapid emergency medicine score (REMS) are two physiologic models for measuring injury severity in emergency settings. The present study was designed to compare the two models in outcome prediction of trauma patients presenting to emergency department (ED). Methods: In this prospective cross-sectional study, the two models of RAPS and REMS were compared regarding prediction of mortality and poor outcome (severe disability based on Glasgow outcome scale) of trauma patients presenting to the EDs of 5 educational hospitals in Iran (Tehran, Tabriz, Urmia, Jahrom and Ilam) from May to October 2016. The discriminatory power and calibration of the models were calculated and compared using STATA 11. Results: 2148 patients with the mean age of 39.50±17.27 years were studied (75.56% males). The area under the curve of REMS and RAPS in predicting in-hospital mortality were calculated to be 0.93 (95% CI: 0.92-0.95) and 0.899 (95% CI: 0.86-0.93), respectively (p=0.02). These measures were 0.92 (95% CI: 0.90-0.94) and 0.86 (95% CI: 0.83-0.90), respectively, regarding poor outcome (p=0.001). The optimum cut-off point in predicting outcome was found to be 3 for REMS model and 2 for RAPS model. The sensitivity and specificity of REMS and RAPS in the mentioned cut offs were 95.93 vs. 85.37 and 77.63 vs. 83.51, respectively, in predicting mortality. Calibration and overall performance of the two models were acceptable. Conclusion: The present study showed that adding age and level of arterial oxygen saturation to the variables included in RAPS model can increase its predictive value. Therefore, it seems that REMS could be used for predicting mortality and poor outcome of trauma patients in emergency settings. PMID:28286837

  15. Examining the Attitudes and Physiological Responses Preservice Learners Have towards Children with Autism Spectrum Disorders

    ERIC Educational Resources Information Center

    Gouvousis, Aphroditi; Heilmann, John; Golden, Jeanne; Kalinowski, Joseph; Hudson, Suzanne; Hough, Monica Strauss

    2010-01-01

    This study investigated attitudes and physiological responses demonstrated by preservice learners towards young children with autism spectrum disorders (ASD). The Self-Assessment Manikin (SAM) and two physiological measures (skin conductance and heart rate responses) were obtained. Four behaviors (two control and two problematic) depicting…

  16. Behavioral and Physiological Response of Baleen Whales to Ships and Ship Noise

    DTIC Science & Technology

    2014-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Behavioral and Physiological Response of Baleen Whales ...LONG-TERM GOALS This study began in late 2013 with the primary goal of examining the behavioral and physiological response of baleen whales to...species including blue and right whales that appear to be particularly susceptible. Initial research demonstrated the feasibility of documenting whale

  17. Physiological Responses to Two Hypoxic Conditioning Strategies in Healthy Subjects

    PubMed Central

    Chacaroun, Samarmar; Borowik, Anna; Morrison, Shawnda A.; Baillieul, Sébastien; Flore, Patrice; Doutreleau, Stéphane; Verges, Samuel

    2017-01-01

    Objective: Hypoxic exposure can be used as a therapeutic tool by inducing various cardiovascular, neuromuscular, and metabolic adaptations. Hypoxic conditioning strategies have been evaluated in patients with chronic diseases using either sustained (SH) or intermittent (IH) hypoxic sessions. Whether hypoxic conditioning via SH or IH may induce different physiological responses remains to be elucidated. Methods: Fourteen healthy active subjects (7 females, age 25 ± 8 years, body mass index 21.5 ± 2.5 kg·m−2) performed two interventions in a single blind, randomized cross-over design, starting with either 3 x SH (48 h apart), or 3 x IH (48 h apart), separated by a 2 week washout period. SH sessions consisted of breathing a gas mixture with reduced inspiratory oxygen fraction (FiO2), continuously adjusted to reach arterial oxygen saturations (SpO2) of 70–80% for 1 h. IH sessions consisted of 5 min with reduced FiO2 (SpO2 = 70–80%), followed by 3-min normoxia, repeated seven times. During the first (S1) and third (S3) sessions of each hypoxic intervention, cardiorespiratory parameters, and muscle and pre-frontal cortex oxygenation (near infrared spectroscopy) were assessed continuously. Results: Minute ventilation increased significantly during IH sessions (+2 ± 2 L·min−1) while heart rate increased during both SH (+11 ± 4 bpm) and IH (+13 ± 5 bpm) sessions. Arterial blood pressure increased during all hypoxic sessions, although baseline normoxic systolic blood pressure was reduced from S1 to S3 in IH only (−8 ± 11 mmHg). Muscle oxygenation decreased significantly during S3 but not S1, for both hypoxic interventions (S3: SH −6 ± 5%, IH −3 ± 4%); pre-frontal oxygenation decreased in S1 and S3, and to a greater extent in SH vs. IH (−13 ± 3% vs. −6 ± 6%). Heart rate variability indices indicated a significantly larger increase in sympathetic activity in SH vs. IH (lower SDNN, PNN50, and RMSSD values in SH). From S1 to S3, further reduction in

  18. Acute exercise does not induce an acute phase response (APR) in Standardbred trotters.

    PubMed

    Kristensen, Lena; Buhl, Rikke; Nostell, Katarina; Bak, Lars; Petersen, Ellen; Lindholm, Maria; Jacobsen, Stine

    2014-04-01

    The purpose of the study was to investigate whether acute strenuous exercise (1600- to 2500-m race) would elicit an acute phase response (APR) in Standardbred trotters. Blood levels of several inflammatory markers [serum amyloid A (SAA), haptoglobin, fibrinogen, white blood cell count (WBC), and iron], muscle enzymes [creatinine kinase (CK) and aspartate transaminase (AST)], and hemoglobin were assessed in 58 Standardbred trotters before and after racing. Hemoglobin levels increased and iron levels decreased 12 to 14 h after racing and haptoglobin concentrations, white blood cell counts, and iron levels were decreased 2 and/or 7 d after racing. Concentrations of CK, AST, SAA, and fibrinogen were unaltered in response to racing. Acute strenuous exercise did not elicit an acute phase reaction. The observed acute increase in hemoglobin levels and decreases in haptoglobin and iron levels may have been caused by exercise-induced hemolysis, which indicates that horses might experience a condition similar to athlete's anemia in humans. The pathogenesis and clinical implications of the hematological and blood-biochemical changes elicited by acute exercise in Standardbred trotters in the present study warrant further investigation.

  19. Identification of molecular and physiological responses to chronic environmental challenge in an invasive species: the Pacific oyster, Crassostrea gigas

    PubMed Central

    Clark, Melody S; Thorne, Michael A S; Amaral, Ana; Vieira, Florbela; Batista, Frederico M; Reis, João; Power, Deborah M

    2013-01-01

    Understanding the environmental responses of an invasive species is critical in predicting how ecosystem composition may be transformed in the future, especially under climate change. In this study, Crassostrea gigas, a species well adapted to the highly variable intertidal environment, was exposed to the chronic environmental challenges of temperature (19 and 24°C) and pH (ambient seawater and a reduction of 0.4 pH units) in an extended 3-month laboratory-based study. Physiological parameters were measured (condition index, shell growth, respiration, excretion rates, O:N ratios, and ability to repair shell damage) alongside molecular analyses. Temperature was by far the most important stressor, as demonstrated by reduced condition indexes and shell growth at 24°C, with relatively little effect detected for pH. Transcriptional profiling using candidate genes and SOLiD sequencing of mantle tissue revealed that classical “stress” genes, previously reported to be upregulated under acute temperature challenges, were not significantly expressed in any of the treatments, emphasizing the different response between acute and longer term chronic stress. The transcriptional profiling also elaborated on the cellular responses underpinning the physiological results, including the identification of the PI3K/AKT/mTOR pathway as a potentially novel marker for chronic environmental challenge. This study represents a first attempt to understand the energetic consequences of cumulative thermal stress on the intertidal C. gigas which could significantly impact on coastal ecosystem biodiversity and function in the future. PMID:24223268

  20. Physiological responses of dwarf coconut seedlings irrigated with saline water

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The use of salt-tolerant plants is an important alternative to cope with the problem of salinity in semi-arid regions. The dwarf coconut palm (Cocos nucifera L.) has emerged as a salt-tolerant crop once established. However, little is known about the physiological mechanisms that may contribute to t...

  1. Physiological genomics of abiotic stress responses in peanut

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Peanut (Arachis hypogaea L.) accessions from the U.S. mini-core collection were independently evaluated for heat and water-deficit stress tolerance using a battery of physiological assays including leaf-level gas exchange, chlorophyll fluorescence yield, membrane thermostability, leaf sugar content,...

  2. Remote Detection of Plant Physiological Responses to TNT Soil Contamination

    DTIC Science & Technology

    2010-01-01

    were significantly affected by TNT exposure at all treatment levels, and photosynthetic decline likely resulted from metabolic impairment rather than...exposure at all treatment levels, and photosynthetic decline likely resulted from metabolic impairment rather than stomatal closure as the experiment...Physiological measurements were significantly affect- ed by TNT exposure at all treatment levels, and photosynthetic decline likely resulted from

  3. [Enteroviruses responsible for acute hemorrhagic conjunctivitis].

    PubMed

    Lévêque, N; Huguet, P; Norder, H; Chomel, J-J

    2010-04-01

    Acute hemorrhagic conjunctivitis (AHC) is an epidemic form of highly contagious conjunctivitis, characterized by conjunctival hemorrhages. The first AHC outbreak was described in 1969 in Ghana, West Africa, and was called Apollo disease, from the Apollo landing on the moon. This outbreak was caused by Enterovirus 70 (EV70) together with a Coxsackievirus A24 (CVA24v) variant, which are the major etiological agents involved in AHC outbreaks worldwide. AHC is known to be directly transmitted by close person-to-person contact or indirectly through soiled ophthalmological materials or unsafe recreational water. Recently, a possible airborne virus spread was suggested which could explain the high transmission rate of the disease. In the absence of a specific antiviral therapy, a rapid diagnosis of the causative agent is required to distinguish AHC due to enteroviruses from other ocular infectious diseases, for there are active drugs, or to quickly implement proper public health measures to limit the extension of the outbreak. However, virus identification remains difficult and time-consuming. Moreover, virological diagnosis is difficult to implement in developing countries where AHC has recently become a major problem for public health.

  4. Evolutionary history underlies plant physiological responses to global change since the last glacial maximum.

    PubMed

    Becklin, Katie M; Medeiros, Juliana S; Sale, Kayla R; Ward, Joy K

    2014-06-01

    Assessing family- and species-level variation in physiological responses to global change across geologic time is critical for understanding factors that underlie changes in species distributions and community composition. Here, we used stable carbon isotopes, leaf nitrogen content and stomatal measurements to assess changes in leaf-level physiology in a mixed conifer community that underwent significant changes in composition since the last glacial maximum (LGM) (21 kyr BP). Our results indicate that most plant taxa decreased stomatal conductance and/or maximum photosynthetic capacity in response to changing conditions since the LGM. However, plant families and species differed in the timing and magnitude of these physiological responses, and responses were more similar within families than within co-occurring species assemblages. This suggests that adaptation at the level of leaf physiology may not be the main determinant of shifts in community composition, and that plant evolutionary history may drive physiological adaptation to global change over recent geologic time.

  5. Physiological and Neuromuscular Response to a Simulated Sprint-Distance Triathlon: Effect of Age Differences and Ability Level.

    PubMed

    García-Pinillos, Felipe; Cámara-Pérez, José C; González-Fernández, Francisco T; Párraga-Montilla, Juan A; Muñoz-Jiménez, Marcos; Latorre-Román, Pedro Á

    2016-04-01

    This study aimed to describe the acute impact of a simulated sprint-distance triathlon at physiological and neuromuscular levels and to determine whether age and athletic performance influenced the response in triathletes. Nineteen triathletes performed a sprint-distance triathlon under simulated conditions. Cardiovascular response was monitored during the race. Rate of perceived exertion along with muscular performance parameters (countermovement jump [CMJ], squat jump [SJ], and handgrip strength test [HS]) were tested at pre- and posttest and during every transition, while a 20-m sprint test (S20m) was performed before and after the race. Blood lactate was recorded postrace. A repeated measures analysis of variance showed that the neuromuscular response-in terms of CMJ, SJ, and HS-was unchanged (p ≥ 0.05), while S20m performance was impaired at posttest (p < 0.001). A linear regression analysis showed that ΔCMJ predicted the overall race time (R = 0.226; p = 0.046). In addition, 2 cluster analyses (k-means) were performed by grouping according to athletic performance and age. Between-group comparison showed no significant differences in the impact of the race at either the physiological or the neuromuscular level. The results showed that muscular performance parameters were not impaired throughout the race despite high levels of fatigue reported. However, despite maintaining initial levels of muscle force after the race, the fatigue-induced changes in S20m were significant, which could reinforce the need to train sprint ability in endurance athletes. Finally, despite the differences in ability level or in age, the acute physiological and neuromuscular responses to a simulated sprint-distance triathlon were similar.

  6. Heart rate responses to standardized trauma-related pictures in acute posttraumatic stress disorder

    PubMed Central

    Ehlers, Anke; Suendermann, Oliver; Boellinghaus, Inga; Vossbeck-Elsebusch, Anna; Gamer, Matthias; Briddon, Emma; Martin, Melanie Walwyn; Glucksman, Edward

    2010-01-01

    Physiological responses to trauma reminders are one of the core symptoms of posttraumatic stress disorder (PTSD). Nevertheless, screening measures for PTSD largely rely on symptom self-reports. It has been suggested that psychophysiological assessments may be useful in identifying trauma survivors with PTSD (Orr and Roth, 2000). This study investigated whether heart rate (HR) responses to standardized trauma-related pictures distinguish between trauma survivors with and without acute PTSD. Survivors of motor vehicle accidents or physical assaults (N = 162) watched standardized trauma-related, generally threatening and neutral pictures at 1 month post-trauma while their ECG was recorded. At 1 and 6 months, structured clinical interviews assessed PTSD diagnoses. Participants completed self-report measures of PTSD severity and depression, peritraumatic responses, coping behaviors and appraisals. Trauma survivors with acute PTSD showed greater HR responses to trauma-related pictures than those without PTSD, as indicated by a less pronounced mean deceleration, greater peak responses, and a greater proportion showing HR acceleration of greater than 1 beat per minute. There were no group differences in HR responses to generally threatening or neutral pictures. HR responses to trauma-related pictures contributed to the prediction of PTSD diagnosis over and above what could be predicted from self-reports of PTSD and depression. HR responses to trauma-related pictures were related to fear and data-driven processing during the trauma, safety behaviors, suppression of trauma memories, and overgeneralized appraisals of danger. The results suggest that HR responses to standardized trauma-related pictures may help identify a subgroup of patients with acute PTSD who show generalized fear responses to trauma reminders. The early generalization of triggers of reexperiencing symptoms observed in this study is consistent with associative learning and cognitive models of PTSD. PMID

  7. Ape Conservation Physiology: Fecal Glucocorticoid Responses in Wild Pongo pygmaeus morio following Human Visitation

    PubMed Central

    Muehlenbein, Michael P.; Ancrenaz, Marc; Sakong, Rosman; Ambu, Laurentius; Prall, Sean; Fuller, Grace; Raghanti, Mary Ann

    2012-01-01

    Nature-based tourism can generate important revenue to support conservation of biodiversity. However, constant exposure to tourists and subsequent chronic activation of stress responses can produce pathological effects, including impaired cognition, growth, reproduction, and immunity in the same animals we are interested in protecting. Utilizing fecal samples (N = 53) from 2 wild habituated orangutans (Pongo pygmaeus morio) (in addition to 26 fecal samples from 4 wild unhabituated orangutans) in the Lower Kinabatangan Wildlife Sanctuary of Sabah, Malaysian Borneo, we predicted that i) fecal glucocorticoid metabolite concentrations would be elevated on the day after tourist visitation (indicative of normal stress response to exposure to tourists on the previous day) compared to samples taken before or during tourist visitation in wild, habituated orangutans, and ii) that samples collected from habituated animals would have lower fecal glucocorticoid metabolites than unhabituated animals not used for tourism. Among the habituated animals used for tourism, fecal glucocorticoid metabolite levels were significantly elevated in samples collected the day after tourist visitation (indicative of elevated cortisol production on the previous day during tourist visitation). Fecal glucocorticoid metabolite levels were also lower in the habituated animals compared to their age-matched unhabituated counterparts. We conclude that the habituated animals used for this singular ecotourism project are not chronically stressed, unlike other species/populations with documented permanent alterations in stress responses. Animal temperament, species, the presence of coping/escape mechanisms, social confounders, and variation in amount of tourism may explain differences among previous experiments. Acute alterations in glucocorticoid measures in wildlife exposed to tourism must be interpreted conservatively. While permanently altered stress responses can be detrimental, preliminary

  8. Surfactant modulates calcium response of neutrophils to physiologic stimulation via cell membrane depolarization.

    PubMed

    Chacon-Cruz, E; Buescher, E S; Oelberg, D G

    2000-03-01

    Pulmonary surfactant (PS) reduces inflammation in the lung by poorly understood mechanisms. We have observed that surfactant-associated proteins (SAP) insert monovalent cation channels in artificial membranes. Neutrophils are primary mediators of acute pulmonary inflammation, and their functions are activated by increases in cytosolic ionized calcium concentration ([Ca2+]) and by changes in membrane potential. We hypothesize that PS inserts SAP-dependent cation channels in neutrophils, causing membrane depolarization, altered [Ca2+] response, and depressed activation. Human neutrophils were isolated, exposed to PS+SAP (1% Survanta), PS-SAP (1% Exosurf), or buffer, and washed before activating with selected stimulants. PS+SAP reduced phorbol ester- and formyl peptide-stimulated adherence and aggregation by 38% (p < 0.05) and 54% (p < 0.02), respectively. PS+SAP also inhibited the formyl peptide-induced [Ca2+] response of neutrophils (p < 0.01), but only in the presence of external Ca2+. Further characterization of this inhibition demonstrated that PS+SAP blocked formyl peptide-induced influx of both Ca2+ and Mn2+, and that this inhibition was present during activation by other neutrophil stimulants (IL-8, immune complexes). Prior depolarization of neutrophils with gramicidin-D similarly inhibited the [Ca2+] response of neutrophils to formyl peptide, and analysis of neutrophil membrane potential by 3,3'-dipentyloxaearbocyanine iodide (diOC5(3)) fluorescence revealed that PS+SAP induced rapid neutrophil depolarization. In contrast, PS-SAP exhibited little effect on neutrophil function, [Ca2+], or membrane potential. We conclude that PS+SAP decreases neutrophil adherence and aggregation responses, blocks Ca2+ influx after physiologic stimulation, and decreases membrane potential. We speculate that these effects are caused by membrane depolarization via SAP-dependent cation channel insertion, and that all of these effects contribute to the antiinflammatory properties of

  9. Ape conservation physiology: fecal glucocorticoid responses in wild Pongo pygmaeus morio following human visitation.

    PubMed

    Muehlenbein, Michael P; Ancrenaz, Marc; Sakong, Rosman; Ambu, Laurentius; Prall, Sean; Fuller, Grace; Raghanti, Mary Ann

    2012-01-01

    Nature-based tourism can generate important revenue to support conservation of biodiversity. However, constant exposure to tourists and subsequent chronic activation of stress responses can produce pathological effects, including impaired cognition, growth, reproduction, and immunity in the same animals we are interested in protecting. Utilizing fecal samples (N = 53) from 2 wild habituated orangutans (Pongo pygmaeus morio) (in addition to 26 fecal samples from 4 wild unhabituated orangutans) in the Lower Kinabatangan Wildlife Sanctuary of Sabah, Malaysian Borneo, we predicted that i) fecal glucocorticoid metabolite concentrations would be elevated on the day after tourist visitation (indicative of normal stress response to exposure to tourists on the previous day) compared to samples taken before or during tourist visitation in wild, habituated orangutans, and ii) that samples collected from habituated animals would have lower fecal glucocorticoid metabolites than unhabituated animals not used for tourism. Among the habituated animals used for tourism, fecal glucocorticoid metabolite levels were significantly elevated in samples collected the day after tourist visitation (indicative of elevated cortisol production on the previous day during tourist visitation). Fecal glucocorticoid metabolite levels were also lower in the habituated animals compared to their age-matched unhabituated counterparts. We conclude that the habituated animals used for this singular ecotourism project are not chronically stressed, unlike other species/populations with documented permanent alterations in stress responses. Animal temperament, species, the presence of coping/escape mechanisms, social confounders, and variation in amount of tourism may explain differences among previous experiments. Acute alterations in glucocorticoid measures in wildlife exposed to tourism must be interpreted conservatively. While permanently altered stress responses can be detrimental, preliminary results

  10. THE ACUTE PHASE RESPONSE INDUCED BY BRONCHOSCOPY WITH LAVAGE

    EPA Science Inventory

    Bronchoscopy has been used to evaluate the inflammatory responses in vitro and in vivo. The procedure may affect acute inflammation in the lower respiratory tract. We reviewed consecutive bronchoscopies done in normal healthy non-smokers between April, 1998 and April, 2004. The...

  11. Acute khat use reduces response conflict in habitual users

    PubMed Central

    Colzato, Lorenza S.; Sellaro, Roberta; Ruiz, Manuel J.; Sikora, Katarzyna; Hommel, Bernhard

    2013-01-01

    Khat consumption has become a worldwide phenomenon broadening from Eastern Africa and the south west of the Arabian Peninsula to ethnic communities in the rest of the world. So far, the cognitive effects of khat use are poorly understood and no studies have looked into the relation between acute khat use and cognitive control functions, the way we control our thoughts and goal directed behavior. We studied how acute khat use affects the emergence and the resolution of response conflict, a central cognitive control function. Khat users (n = 11) and khat-free controls (n = 18) were matched in terms of education, sex, alcohol, and cannabis consumption. Groups were tested on response conflict, as measured by the Simon task. In one single session, participants worked through two task blocks: the khat group chewed exclusively khat whereas the khat-free group chewed solely a gum. Results showed that in the second block, which reflects the acute impact of khat, the khat group was better than controls in resolving stimulus-induced response conflict as indexed by a smaller Simon effect. These results suggest that the acute intake of khat may improve participants' ability of handling response conflict. PMID:23801952

  12. Physiological responses to rock climbing in young climbers.

    PubMed

    Morrison, Audry Birute; Schöffl, Volker Rainer

    2007-12-01

    Key questions regarding the training and physiological qualities required to produce an elite rock climber remain inadequately defined. Little research has been done on young climbers. The aim of this paper was to review literature on climbing alongside relevant literature characterising physiological adaptations in young athletes. Evidence-based recommendations were sought to inform the training of young climbers. Of 200 studies on climbing, 50 were selected as being appropriate to this review, and were interpreted alongside physiological studies highlighting specific common development growth variables in young climbers. Based on injury data, climbers younger than 16 years should not participate in international bouldering competitions and intensive finger strength training is not recommended. The majority of climbing foot injuries result from wearing too small or unnaturally shaped climbing shoes. Isometric and explosive strength improvements are strongly associated with the latter stages of sexual maturation and specific ontogenetic development, while improvement in motor abilities declines. Somatotyping that might identify common physical attributes in elite climbers of any age is incomplete. Accomplished adolescent climbers can now climb identical grades and compete against elite adult climbers aged up to and >40 years. High-intensity sports training requiring leanness in a youngster can result in altered and delayed pubertal and skeletal development, metabolic and neuroendocrine aberrations and trigger eating disorders. This should be sensitively and regularly monitored. Training should reflect efficacious exercises for a given sex and biological age.

  13. Physiological responses to environmental factors related to space flight. [hemodynamic and metabolic responses to weightlessness

    NASA Technical Reports Server (NTRS)

    Pace, N.

    1973-01-01

    Physiological base line data are established, and physiological procedures and instrumentation necessary for the automatic measurement of hemodynamic and metabolic parameters during prolonged periods of weightlessness are developed.

  14. Differentiated Ratings of Perceived Exertion and Selected Physiological Responses during Prolonged Upper and Lower Body Exercise,

    DTIC Science & Technology

    1983-10-01

    AC and CY exercise for any of the diff RPE. Local RPE was generally higher than central RPE. Selected physiological responses accounted for more... physiological responses was much higher for arm crank than cycle exercise for W7 T-7 7’v* 7 7. 7 77 7 9 w2 all differentiated RPE contrasts (ABS and REL-AC...total accountable variance from these selected physiological responses was greater for arm crank (median R2 = 0.99) than cycle exercise (median R 2 = 0.75

  15. Evaluation of simplified acute physiology score 3 performance: a systematic review of external validation studies

    PubMed Central

    2014-01-01

    Introduction Simplified Acute Physiology Score 3 (SAPS 3) was the first critical care prognostic model developed from worldwide data. We aimed to systematically review studies that assessed the prognostic performance of SAPS 3 general and customized models for predicting hospital mortality in adult patients admitted to the ICU. Methods Medline, Lilacs, Scielo and Google Scholar were searched to identify studies which assessed calibration and discrimination of general and customized SAPS 3 equations. Additionally, we decided to evaluate the correlation between trial size (number of included patients) and the Hosmer-Lemeshow (H-L) statistics value of the SAPS 3 models. Results A total of 28 studies were included. Of these, 11 studies (42.8%) did not find statistically significant mis-calibration for the SAPS 3 general equation. There was a positive correlation between number of included patients and higher H-L statistics, that is, a statistically significant mis-calibration of the model (r = 0.747, P <0.001). Customized equations for major geographic regions did not have statistically significant departures from perfect calibration in 9 of 19 studies. Five studies (17.9%) developed a regional customization and in all of them this new model was not statistically different from a perfect calibration for their populations. Discrimination was at least very good in 24 studies (85.7%). Conclusions Statistically significant departure from perfect calibration for the SAPS 3 general equation was common in validation studies and was correlated with larger studies, as should be expected, since H-L statistics (both C and H) are strongly dependent on sample size This finding was also present when major geographic customized equations were evaluated. Local customizations, on the other hand, improved SAPS 3 calibration. Discrimination was almost always very good or excellent, which gives excellent perspectives for local customization when a precise local estimate is needed

  16. Physiological variables associated with the development of acute mountain sickness at the South Pole

    PubMed Central

    Harrison, Michael F; Anderson, Paul J; Miller, Andrew D; O'Malley, Kathy A; Richert, Maile L; Johnson, Jacob B; Johnson, Bruce D

    2013-01-01

    Exposure to altitudes >2500 m can result in acute mountain sickness (AMS), a mild and usually self-limiting condition. Research has attempted to identify factors associated with developing AMS without controlling important factors related to the ascent or collecting a comprehensive set of variables. Objectives The Antarctic Study of Altitude Physiology (ASAP) investigated variables associated with the development of AMS in adults experiencing rapid passive transport to altitude by airplane. Design Our prospective observational trial collected data, including personal history, anthropometrics, vital signs, blood samples and pulmonary function, at sea level and at altitude. Statistical analysis utilised independent sample t tests to investigate between-group differences (p<0.05) and a forward, step-wise binary logisitic regression analysis was performed. Participants Of 248 eligible ASAP participants, those who did not use acetazolamide (N=98) were included in the present analysis. Primary outcome measures The diagnosis of AMS using the Lake Louise Symptom Score. Results Analysis of participants not using acetazolamide (n=90) found 30 participants developed AMS and 60 participants did not. Estimated plasma volume decreased significantly at altitude (p=0.025) in the AMS group as compared with the No AMS group while body weight did not change (p=0.125). Serum sodium (p=0.045) and low-density lipoprotein (LDL) (p=0.049) levels were higher in the No AMS group. A logistic regression analysis emphasised the contributions of LDL and eosinophil levels in the development of AMS. Conclusions These results suggest that the body water regulation and inflammation are key factors in AMS development when all other factors such as the level of physical exertion during ascent, the rate and magnitude of ascent and the use of acetazolamide are controlled. PMID:23869103

  17. Acute promyelocytic leukemia: new issues on pathogenesis and treatment response.

    PubMed

    Vitoux, Dominique; Nasr, Rihab; de The, Hugues

    2007-01-01

    Pathogenesis of acute promyelocytic leukemia appears to be one of the best understood among human malignancies. The ability of retinoic acid (RA) and arsenic trioxide to directly target the oncogenic promyelocytic leukemia-retinoic receptor A (PML-RARA) fusion protein also made this disease the first model for oncogene-targeted therapies. A set of recent data has significantly increased the complexity of our view of acute promyelocytic leukemia pathogenesis, as well as of therapeutic response. This review summarizes and discusses these findings, which yield novels questions and models.

  18. Automated system for integration and display of physiological response data

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The system analysis approach was applied in a study of physiological systems in both 1-g and weightlessness, for short and long term experiments. A whole body, algorithm developed as the first step in the construction of a total body simulation system is described and an advanced biomedical computer system concept including interactive display/command consoles is discussed. The documentation of the design specifications, design and development studies, and user's instructions (which include program listings) for these delivered end-terms; the reports on the results of many research and feasibility studies; and many subcontract reports are cited in the bibliography.

  19. The glucose intolerance of acute pancreatitis: hormonal response to arginine.

    PubMed

    Solomon, S S; Duckworth, W C; Jallepalli, P; Bobal, M A; Iyer, R

    1980-01-01

    Patients with acute pancreatitis were studied by arginine infusion at 48--72 h. 7--10 days, and 18--21 days after onset of their illness. Plasma glucose, insulin, and glucagon values were determined. Acute pancreatitis was characterized by fasting hyperglycemia and hyperglucagonemia, associated with relative hyoinsulinemia. Arginine stimulation early in the disease (48--72 h) demonstrated hyperglycemia and hyperglucagonemia, which normalized by 18--21 days. Both phases of the normal biphasic insulin response to arginine were decreased during the initial arginine infusion. By 18--21 days, although the first phase was completely normal, the second phase of insulin secretion remained depressed. Acute pancreatitis is associated with damage to both the endocrine and exocrine pancreas. Glucose intolerance seen with this disease appears to be the result of hyperglucagonemia and relative hypoinsulinemia. Although the healing process at 3 wk is associated with return of plasma glucose and glucagon concentrations to normal, the impaired second phase insulin secretion persists.

  20. Physiological responses of plant leaves to atmospheric ammonia and ammonium

    NASA Astrophysics Data System (ADS)

    Pearson, J.; Soares, A.

    Misting of leaves of several plant species with 3 mM aqueous NH +4 at pH 5, or fumigation with 3000 μg m -3 gaseous NH 3 for 1 h, elicits similar biochemical and physiological changes in the species tested. The enzyme glutamine synthetase (GS) was shown to increase its activity in all species, while that of nitrate reductase (NR) was inhibited, at least in those species which possessed the ability to induce foliar NR. At the same time there were marked changes in organic anion concentrations, with malate and citrate in particular being reduced in concentration, following either NH +4 or NH 3 application to leaves. The changes in organic anions are also discussed in the light of pH regulation by the cell. A stimulation of photosynthesis was also evident when leaves were treated with either NH 3 or NH +4. It is argued that, because of the differences in solution chemistry of the two ammonia forms, the aqueous form applied at pH 5 and the gaseous form being an alkali in solution, these changes can only have occurred through the ability of the leaves to readily assimilate both forms of the ammonia. The biochemical changes might have potential as markers for the onset of physiological perturbation by atmospheric ammonia pollution, particularly changes in organic acid concentration; their use in an index of pollution stress is briefly discussed.

  1. Behavioral and physiological responses in felids to exhibit construction.

    PubMed

    Chosy, Julia; Wilson, Megan; Santymire, Rachel

    2014-01-01

    Despite the growing body of literature examining the welfare of zoo-housed animals, little standardized work has been published on the effect of construction and environmental disruption on the physiology and behavior of affected animals. When Lincoln Park Zoo (Chicago, IL), embarked on a renovation project for its Kovler Lion House, the opportunity was taken to perform a scientific study of behavioral and physiological markers in the resident felids to determine the effect of construction and environmental disruption. Fecal samples and behavioral observations were collected on four felid species (five individuals) before, during, and after the period of construction. As a group, the average z-score for fecal glucocorticoid metabolite concentration increased during construction relative to baseline. Levels remained elevated after construction, but trended toward baseline. All individuals demonstrated a significant decrease in the frequency of pacing and time spent visible during construction. Overall activity levels also showed a significant decrease relative to baseline measures. As zoological institutions continue to recognize the importance of habitat design, construction and renovation become inevitable. It is important to be aware of the potential consequences this can have on animals in the vicinity and to work toward minimizing negative effects. One recommendation is the availability of ample retreat and hiding space for felids during disruption to their environment.

  2. Physiologic responses of grizzly bears to different methods of capture.

    PubMed

    Cattet, Marc R; Christison, Katina; Caulkett, Nigel A; Stenhouse, Gordon B

    2003-07-01

    The physiologic effects of two methods of capture, chemical immobilization of free-ranging (FR) bears by remote injection from a helicopter and physical restraint (PR) by leg-hold snare prior to chemical immobilization, were compared in 46 grizzly bears (Ursus arctos) handled during 90 captures between 1999 and 2001. Induction dosages and times were greater for FR bears than PR bears, a finding consistent with depletion of, or decreased sensitivity to, catecholamines. Free-ranging bears also had higher rectal temperatures 15 min following immobilization and temperatures throughout handling that correlated positively with induction time. Physically restrained bears had higher white blood cell counts, with more neutrophils and fewer lymphocytes and eosinophils, than did FR bears. This white blood cell profile was consistent with a stress leukogram, possibly affected by elevated levels of serum cortisol. Serum concentrations of alanine aminotransferase, aspartate aminotransferase, and creatine kinase were higher in PR bears that suggested muscle injury. Serum concentrations of sodium and chloride also were higher in PR bears and attributed to reduced body water volume through water deprivation and increased insensible water loss. Overall, different methods of capture resulted in different patterns of physiologic disturbance. Reducing pursuit and drug induction times should help to minimize increase in body temperature and alteration of acid-base balance in bears immobilized by remote injection. Minimizing restraint time and ensuring snare-anchoring cables are short should help to minimize loss of body water and prevent serious muscle injury in bears captured by leg-hold snare.

  3. Physiological responses of Daphnia pulex to acid stress

    PubMed Central

    Weber, Anna K; Pirow, Ralph

    2009-01-01

    Background Acidity exerts a determining influence on the composition and diversity of freshwater faunas. While the physiological implications of freshwater acidification have been intensively studied in teleost fish and crayfish, much less is known about the acid-stress physiology of ecologically important groups such as cladoceran zooplankton. This study analyzed the extracellular acid-base state and CO2 partial pressure (PCO2), circulation and ventilation, as well as the respiration rate of Daphnia pulex acclimated to acidic (pH 5.5 and 6.0) and circumneutral (pH 7.8) conditions. Results D. pulex had a remarkably high extracellular pH of 8.33 and extracellular PCO2 of 0.56 kPa under normal ambient conditions (pH 7.8 and normocapnia). The hemolymph had a high bicarbonate concentration of 20.9 mM and a total buffer value of 51.5 meq L-1 pH-1. Bicarbonate covered 93% of the total buffer value. Acidic conditions induced a slight acidosis (ΔpH = 0.16–0.23), a 30–65% bicarbonate loss, and elevated systemic activities (tachycardia, hyperventilation, hypermetabolism). pH 6.0 animals partly compensated the bicarbonate loss by increasing the non-bicarbonate buffer value from 2.0 to 5.1 meq L-1 pH-1. The extracellular PCO2 of pH 5.5 animals was significantly reduced to 0.33 kPa, and these animals showed the highest tolerance to a short-term exposure to severe acid stress. Conclusion Chronic exposure to acidic conditions had a pervasive impact on Daphnia's physiology including acid-base balance, extracellular PCO2, circulation and ventilation, and energy metabolism. Compensatory changes in extracellular non-bicarbonate buffering capacity and the improved tolerance to severe acid stress indicated the activation of defense mechanisms which may result from gene-expression mediated adjustments in hemolymph buffer proteins and in epithelial properties. Mechanistic analyses of the interdependence between extracellular acid-base balance and CO2 transport raised the question of

  4. Physiological responses of Chinese longsnout catfish to water temperature

    NASA Astrophysics Data System (ADS)

    Han, Dong; Xie, Shouqi; Zhu, Xiaoming; Yang, Yunxia

    2011-05-01

    We evaluated the effect of water temperature on the growth and physiology of the Chinese longsnout catfish ( Leiocassis longirostris Günther). The fish were reared at four temperatures (20, 25, 30, and 35°C) and sampled on days 7, 20, and 30. We measured plasma levels of insulin, free thyroxine (FT4), free 3,5,3'-triiodothyronine (FT3), lysozyme and leukocyte phagocytic activity. The optimum water temperature for growth was 27.7°C. The plasma levels of insulin and FT4 declined significantly ( P<0.05) on day 30 at temperatures above 20°C. Lysozyme activity was significantly ( P<0.05) lower at 25°C than at other temperatures. We conclude that final weight, insulin, FT4, and lysozyme were significantly affected by water temperature.

  5. Physiological responses to Tai Chi in stable patients with COPD.

    PubMed

    Qiu, Zhi-Hui; Guo, Hong-Xi; Lu, Gan; Zhang, Ning; He, Bai-Ting; Zhou, Lian; Luo, Y M; Polkey, M I

    2016-01-15

    We compared the physiological work, judged by oxygen uptake, esophageal pressure swing and diaphragm electromyography, elicited by Tai Chi compared with that elicited by constant rate treadmill walking at 60% of maximal load in eleven patients with COPD (Mean FEV1 61% predicted, FEV1/FVC 47%). Dynamic hyperinflation was assessed by inspiratory capacity and twitch quadriceps tension (TwQ) elicited by supramaximal magnetic stimulation of the femoral nerve was also measured before and after both exercises. The EMGdi and esophageal pressure at the end of exercise were similar for both treadmill exercise and Tai Chi (0.109±0.047 mV vs 0.118±0.061 mV for EMGdi and 22.3±7.1 cmH2O vs 21.9±8.1 cmH2O for esophageal pressure). Moreover the mean values of oxygen uptake during Tai Chi and treadmill exercise did not differ significantly: 11.3 ml/kg/min (51.1% of maximal oxygen uptake derived from incremental exercise) and 13.4 ml/kg/min (52.5%) respectively, p>0.05. Respiratory rate during Tai Chi was significantly lower than that during treadmill exercise. Both Tai Chi and treadmill exercise elicited a fall in IC at end exercise, indicating dynamic hyperinflation, but this was statistically significant only after treadmill exercise. TwQ decreased significantly after Tai Chi but not after treadmill. We conclude that Tai Chi constitutes a physiologically similar stimulus to treadmill exercise and may therefore be an acceptable modality for pulmonary rehabilitation which may be culturally more acceptable in some parts of the world.

  6. Physiological responses in a Concealed Information Test are determined interactively by encoding procedure and questioning format.

    PubMed

    Ambach, Wolfgang; Dummel, Sebastian; Lüer, Theresa; Vaitl, Dieter

    2011-09-01

    Physiological responses in the Concealed Information Test (CIT) are known to depend on the depth of encoding critical items; CIT questions commonly refer to knowledge about critical items. It is unclear to what extent (1) different modes of item handling in a mock-crime, and (2) alternative questioning formats, e.g. asking about participants' particular actions with the critical items, influence the physiological responses. In the presented mock-crime study with fifty-three participants, two questioning formats, i.e. "Did you see …?" (viewing questioning) and "Did you steal …?" (stealing questioning), were compared between subjects. The mode of encoding, stealing vs. merely viewing the critical objects, was varied within subject. Skin conductance, electrocardiogram, respiration, and finger pulse were recorded. For both questioning formats and each physiological measure, physiological responses to stolen as well as merely viewed objects differed from those to irrelevant objects. Considering viewing questioning, responses to stolen and merely viewed objects did not differ, with the exception of greater phasic decreases of heart rate for stolen objects. Considering stealing questioning, responses to stolen objects exceeded those to merely viewed objects with each physiological measure. The statistically proven interaction between mode of encoding a particular object and questioning format sheds light on the factors influencing the physiological responses in a CIT. The level of subjective significance of a particular item might emerge interactively from the mode of item handling and the questioning format.

  7. Affective and physiological responses to stress in girls at elevated risk for depression

    PubMed Central

    WAUGH, CHRISTIAN E.; MUHTADIE, LUMA; THOMPSON, RENEE J.; JOORMANN, JUTTA; GOTLIB, IAN H.

    2015-01-01

    Children of depressed parents are significantly more likely to develop depression and other mental health disorders than are children of never-depressed parents. Investigations of the physiological mechanisms underlying this elevated risk have generally focused on basal functioning. It is important to note, however, that physiological reactivity or responses to stress are also critical determinants of mental and physical health. In the current study, we examined whether children of depressed parents exhibit altered physiological responses to stress. In two studies, never-depressed adolescent daughters of either recurrently depressed mothers (RISK) or never-depressed mothers (CTL) underwent social stressors while their physiological responses were measured (cortisol in Study 1, heart rate in Study 2). In both studies, affective responses to the stressors predicted physiological responses in RISK girls, but not in never-depressed girls. For RISK girls, decreased positive affect in response to stress predicted increased cortisol reactivity; in addition, decreased positive affect and increased negative affect were associated with poorer heart rate recovery and habituation, respectively. Future research is needed to examine explicitly whether this coherence between affect and physiology is a mechanism underlying the increased risk for psychopathology in children of depressed parents. PMID:22559138

  8. Freeze, flight, fight, fright, faint: adaptationist perspectives on the acute stress response spectrum.

    PubMed

    Bracha, H Stefan

    2004-09-01

    This article reviews the existing evolutionary perspectives on the acute stress response habitual faintness and blood-injection-injury type-specific phobia (BIITS phobia). In this article, an alternative evolutionary perspective, based on recent advances in evolutionary psychology, is proposed. Specifically, that fear-induced faintness (eg, fainting following the sight of a syringe, blood, or following a trivial skin injury) is a distinct Homo sapiens-specific extreme-stress survival response to an inescapable threat. The article suggests that faintness evolved in response to middle paleolithic intra-group and inter-group violence (of con-specifics) rather than as a pan-mammalian defense response, as is presently assumed. Based on recent literature, freeze, flight, fight, fright, faint provides a more complete description of the human acute stress response sequence than current descriptions. Faintness, one of three primary physiological reactions involved in BIITS phobia, is extremely rare in other phobias. Since heritability estimates are higher for faintness than for fears or phobias, the author suggests that trait-faintness may be a useful complement to trait-anxiety as an endophenotype in research on the human fear circuitry. Some implications for the forthcoming Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition as well as for clinical, health services, and transcriptomic research are briefly discussed.

  9. microRNA function is limited to cytokine control in the acute response to virus infection

    PubMed Central

    Aguado, Lauren C.; Schmid, Sonja; Sachs, David; Shim, Jaehee V.; Lim, Jean K.; tenOever, Benjamin R.

    2015-01-01

    SUMMARY With the capacity to fine-tune protein expression via sequence-specific interactions, microRNAs (miRNAs) help regulate cell maintenance and differentiation. While some studies have also implicated miRNAs as regulators of the antiviral response, others have found that the RISC complex that facilitates miRNA-mediated silencing is rendered non-functional during cellular stress, including virus infection. To determine the global role of miRNAs in the cellular response to virus infection, we generated a vector that rapidly eliminates total cellular miRNA populations in terminally differentiated primary cultures. Loss of miRNAs has a negligible impact on both innate sensing of and immediate response to acute viral infection. In contrast, miRNA depletion specifically enhances cytokine expression, providing a post-translational mechanism for immune cell activation during cellular stress. This work highlights the physiological role of miRNAs during the antiviral response and suggests their contribution is limited to chronic infections and the acute activation of the adaptive immune response. PMID:26651947

  10. Acute-phase responses vary with pathogen identity in house sparrows (Passer domesticus).

    PubMed

    Coon, Courtney A C; Warne, Robin W; Martin, Lynn B

    2011-06-01

    Pathogens may induce different immune responses in hosts contingent on pathogen characteristics, host characteristics, or interactions between the two. We investigated whether the broadly effective acute-phase response (APR), a whole body immune response that occurs in response to constitutive immune receptor activation and includes fever, secretion of immune peptides, and sickness behaviors such as anorexia and lethargy, varies with pathogen identity in the house sparrow (Passer domesticus). Birds were challenged with a subcutaneous injection of either a glucan at 0.7 mg/kg (to simulate fungal infection), a synthetic double-stranded RNA at 25 mg/kg (to simulate viral infection), or LPS at 1 mg/kg (to simulate a gram-negative bacterial infection), and then body mass, core body temperature changes, sickness behaviors, and secretion of an acute-phase protein, haptoglobin, were compared. Despite using what are moderate-to-high pyrogen doses for other vertebrates, only house sparrows challenged with LPS showed measurable APRs. Febrile, behavioral, and physiological responses to fungal and viral mimetics had minimal effects.

  11. Fully optimized discrimination of physiological responses to auditory stimuli

    PubMed Central

    Kruglikov, Stepan Y; Chari, Sharmila; Rapp, Paul E; Weinstein, Steven L; Given, Barbara K; Schiff, Steven J

    2008-01-01

    The use of multivariate measurements to characterize brain activity (electrical, magnetic, optical) is widespread. The most common approaches to reduce the complexity of such observations include principal and independent component analyses (PCA and ICA), which are not well suited for discrimination tasks. We addressed two questions: first, how do the neurophysiological responses to elongated phonemes relate to tone and phoneme responses in normal children, and, second, how discriminable are these responses. We employed fully optimized linear discrimination analysis to maximally separate the multi-electrode responses to tones and phonemes, and classified the response to elongated phonemes. We find that discrimination between tones and phonemes is dependent upon responses from associative regions of the brain apparently distinct from the primary sensory cortices typically emphasized by PCA or ICA, and that the neuronal correlates corresponding to elongated phonemes are highly variable in normal children (about half respond with neural correlates of tones and half as phonemes). Our approach is made feasible by the increase in computational power of ordinary personal computers and has significant advantages for a wide range of neuronal imaging modalities. PMID:18430975

  12. Physiological identification and infralimbic responsiveness of rat intercalated amygdala neurons.

    PubMed

    Amir, Alon; Amano, Taiju; Pare, Denis

    2011-06-01

    Intercalated (ITC) amygdala neurons are thought to play a critical role in the extinction of conditioned fear. However, several factors hinder progress in studying ITC contributions to extinction. First, although extinction is usually studied in rats and mice, most ITC investigations were performed in guinea pigs or cats. Thus it is unclear whether their connectivity is similar across species. Second, we lack criteria to identify ITC cells on the basis of their discharge pattern. As a result, key predictions of ITC extinction models remain untested. Among these, ITC cells were predicted to be strongly excited by infralimbic inputs, explaining why infralimbic inhibition interferes with extinction. To study the connectivity of ITC cells, we labeled them with neurobiotin during patch recordings in slices of the rat amygdala. This revealed that medially located ITC cells project topographically to the central nucleus and to other ITC clusters located more ventrally. To study the infralimbic responsiveness of ITC cells, we performed juxtacellular recording and labeling of amygdala cells with neurobiotin in anesthetized rats. All ITC cells were orthodromically responsive to infralimbic stimuli, and their responses usually consisted of high-frequency (~350 Hz) trains of four to six spikes, a response pattern never seen in neighboring amygdala nuclei. Overall, our results suggest that the connectivity of ITC cells is conserved across species and that ITC cells are strongly responsive to infralimbic stimuli, as predicted by extinction models. The unique response pattern of ITC cells to infralimbic stimuli can now be used to identify them in fear conditioning experiments.

  13. Acute caffeine administration affects zebrafish response to a robotic stimulus.

    PubMed

    Ladu, Fabrizio; Mwaffo, Violet; Li, Jasmine; Macrì, Simone; Porfiri, Maurizio

    2015-08-01

    Zebrafish has been recently proposed as a valid animal model to investigate the fundamental mechanisms regulating emotional behavior and evaluate the modulatory effects exerted by psychoactive compounds. In this study, we propose a novel methodological framework based on robotics and information theory to investigate the behavioral response of zebrafish exposed to acute caffeine treatment. In a binary preference test, we studied the response of caffeine-treated zebrafish to a replica of a shoal of conspecifics moving in the tank. A purely data-driven information theoretic approach was used to infer the influence of the replica on zebrafish behavior as a function of caffeine concentration. Our results demonstrate that acute caffeine administration modulates both the average speed and the interaction with the replica. Specifically, zebrafish exposed to elevated doses of caffeine show reduced locomotion and increased sensitivity to the motion of the replica. The methodology developed in this study may complement traditional experimental paradigms developed in the field of behavioral pharmacology.

  14. Stress response in honeybees is associated with changes in task-related physiology and energetic metabolism.

    PubMed

    Bordier, Célia; Suchail, Séverine; Pioz, Maryline; Devaud, Jean Marc; Collet, Claude; Charreton, Mercedes; Le Conte, Yves; Alaux, Cédric

    2017-04-01

    In a rapidly changing environment, honeybee colonies are increasingly exposed to diverse sources of stress (e.g., new parasites, pesticides, climate warming), which represent a challenge to individual and social homeostasis. However, bee physiological responses to stress remain poorly understood. We therefore exposed bees specialised in different tasks (nurses, guards and foragers) to ancient (immune and heat stress) or historically more recent sources of stress (pesticides), and we determined changes in the expression of genes linked to behavioural maturation (vitellogenin - vg and juvenile hormone esterase - jhe) as well as in energetic metabolism (glycogen level, expression level of the receptor to the adipokinetic hormone - akhr, and endothermic performance). While acute exposure to sublethal doses of two pesticides did not affect vg and jhe expression, immune and heat challenges caused a decrease and increase in both genes, respectively, suggesting that bees had responded to ecologically relevant stressors. Since vg and jhe are expressed to a higher level in nurses than in foragers, it is reasonable to assume that an immune challenge stimulated behavioural maturation to decrease potential contamination risk and that a heat challenge promoted a nurse profile for brood thermoregulation. All behavioural castes responded in the same way. Though endothermic performances did not change upon stress exposure, the akhr level dropped in immune and heat-challenged individuals. Similarly, the abdomen glycogen level tended to decline in immune-challenged bees. Altogether, these results suggest that bee responses are stress specific and adaptive but that they tend to entail a reduction of energetic metabolism that needs to be studied on a longer timescale.

  15. Performance and physiological responses to repeated-sprint exercise: a novel multiple-set approach.

    PubMed

    Serpiello, Fabio R; McKenna, Michael J; Stepto, Nigel K; Bishop, David J; Aughey, Robert J

    2011-04-01

    We investigated the acute and chronic responses to multiple sets of repeated-sprint exercise (RSE), focusing on changes in acceleration, intermittent running capacity and physiological responses. Ten healthy young adults (7 males, 3 females) performed an incremental test, a Yo-Yo intermittent recovery test level1 (Yo-Yo IR1), and one session of RSE. RSE comprised three sets of 5 × 4-s maximal sprints on a non-motorised treadmill, with 20 s of passive recovery between repetitions and 4.5 min of passive recovery between sets. After ten repeated-sprint training sessions, participants repeated all tests. During RSE, performance was determined by measuring acceleration, mean and peak power/velocity. Recovery heart rate (HR), HR variability, and finger-tip capillary lactate concentration ([Lac(-)]) were measured. Performance progressively decreased across the three sets of RSE, with the indices of repeated-sprint ability being impaired to a different extent before and after training. Training induced a significant increase (p < 0.05) in all indices of performance, particularly acceleration (21.9, 14.7 and 15.2% during sets 1, 2 and 3, respectively). Training significantly increased Yo-Yo IR1 performance by 8% and decreased Δ[Lac(-)]/work ratio (-15.2, -15.5, -9.4% during sets 1, 2 and 3, respectively) and recovery HR during RSE. There were strong correlations between Yo-Yo IR1 performance and indices of RSE performance, especially acceleration post-training (r = 0.88, p = 0.004). Repeated-sprint training, comprising only 10 min of exercise overall, effectively improved performance during multiple-set RSE. This exercise model better reflects team-sport activities than single-set RSE. The rapid training-induced improvement in acceleration, quantified here for the first time, has wide applications for professional and recreational sport activities.

  16. Regulation by arbuscular mycorrhizae of the integrated physiological response to salinity in plants: new challenges in physiological and molecular studies.

    PubMed

    Ruiz-Lozano, Juan Manuel; Porcel, Rosa; Azcón, Charo; Aroca, Ricardo

    2012-06-01

    Excessive salt accumulation in soils is a major ecological and agronomical problem, in particular in arid and semi-arid areas. Excessive soil salinity affects the establishment, development, and growth of plants, resulting in important losses in productivity. Plants have evolved biochemical and molecular mechanisms that may act in a concerted manner and constitute the integrated physiological response to soil salinity. These include the synthesis and accumulation of compatible solutes to avoid cell dehydration and maintain root water uptake, the regulation of ion homeostasis to control ion uptake by roots, compartmentation and transport into shoots, the fine regulation of water uptake and distribution to plant tissues by the action of aquaporins, the reduction of oxidative damage through improved antioxidant capacity and the maintenance of photosynthesis at values adequate for plant growth. Arbuscular mycorrhizal (AM) symbiosis can help the host plants to cope with the detrimental effects of high soil salinity. There is evidence that AM symbiosis affects and regulates several of the above mentioned mechanisms, but the molecular bases of such effects are almost completely unknown. This review summarizes current knowledge about the effects of AM symbiosis on these physiological mechanisms, emphasizing new perspectives and challenges in physiological and molecular studies on salt-stress alleviation by AM symbiosis.

  17. Cooling cows efficiently with sprinklers: Physiological responses to water spray.

    PubMed

    Chen, Jennifer M; Schütz, Karin E; Tucker, Cassandra B

    2015-10-01

    Dairies in the United States commonly cool cattle with sprinklers mounted over the feed bunk that intermittently spray the cows' backs. These systems use potable water-an increasingly scarce resource--but there is little experimental evidence about how much is needed to cool cows or about droplet size, which is thought to affect hair coat penetration. Our objectives were to determine how sprinkler flow rate and droplet size affect physiological measures of heat load in a hot, dry climate, and to evaluate cooling effectiveness against water use. The treatments were an unsprayed control and 6 soaker nozzles that delivered four 3-min spray applications of 0.4, 1.3, or ≥ 4.5 L/min (with 2 droplet sizes within each flow rate) and resulting in 30 to 47% of spray directly wetting each cow. Data were collected from high-producing lactating Holsteins (n = 19) tested individually in ambient conditions (air temperature = 31.2 ± 3.8°C, mean ± standard deviation). Cows were restrained in headlocks for 1h and received 1 treatment/d for 3d each, with order of exposure balanced in a crossover design. When cows were not sprayed, physiological measures of heat load increased during the 1-h treatment. All measures responded rapidly to spray: skin temperature decreased during the first water application, and respiration rate and body temperature did so before the second. Droplet size had no effect on cooling, but flow rate affected several measures. At the end of 1h, 0.4 L/min resulted in lower respiration rate and skin temperature on directly sprayed body parts relative to the control but not baseline values, and body temperature increased to 0.2°C above baseline. When 1.3 or ≥ 4.5 L/min was applied, respiration rate was lower than the control and decreased relative to baseline, and body temperature stayed below baseline for at least 30 min after treatment ended. The treatment that best balanced cooling effectiveness against water usage was 1.3 L/min: although ≥ 4.5 L

  18. Assessing physiological tipping points in response to ocean acidification

    NASA Astrophysics Data System (ADS)

    Dupont, S. T.; Dorey, N.; Lançon, P.; Thorndyke, M. S.

    2011-12-01

    Impact of near-future ocean acidification on marine invertebrates was mostly assessed in single-species perturbation experiment. Moreover, most of these experiments are short-term, only consider one life-history stage and one or few parameters. They do not take into account important processes such as natural variability and acclimation and evolutionary processes. In many studies published so far, there is a clear lack between the observed effects and individual fitness, most of the deviation from the control being considered as potentially negative for the tested species. However, individuals are living in a fluctuating world and changes can also be interpreted as phenotypic plasticity and may not translate into negative impact on fitness. For example, a vent mussel can survive for decades in very acidic waters despite a significantly reduced calcification compare to control (Tunnicliffe et al. 2009). This is possible thanks to the absence of predatory crabs as a result of acidic conditions that may also inhibit carapace formation. This illustrates the importance to take into account ecological interactions when interpreting single-species experiments and to consider the relative fitness between interacting species. To understand the potential consequence of ocean acidification on any given ecosystem, it is then critical to consider the relative impact on fitness for every interactive species and taking into account the natural fluctuation in environment (e.g. pH, temperature, food concentration, abundance) and discriminate between plasticity with no direct impact on fitness and teratology with direct consequence on survival. In this presentation, we will introduce the concept of "physiological tipping point" in the context of ocean acidification. This will be illustrated by some work done on sea urchin development. Embryos and larvae of the sea urchin Strongylocentrotus droebachiensis were exposed to a range of pH from 8.1 to 6.5. When exposed to low pH, growth

  19. Physiological responses to a tap dance choreography: comparisons with graded exercise test and prescription recommendations.

    PubMed

    Oliveira, Samantha M L; Simões, Herbert G; Moreira, Sergio R; Lima, Ricardo M; Almeida, Jeeser A; Ribeiro, Fabiana M R; Puga, Guilherme M; Campbell, Carmen S G

    2010-07-01

    The aim of this study was to analyze the physiological responses to a tap dance choreography and to compare with those observed during a maximal treadmill exercise test, in tap dancers. Eight women (19.6 +/- 2.4 years; 162.3 +/- 4.4 cm; 54.0 +/- 2.3 kg; 20.5 +/- 1.4 kg.m; and 5.1 +/- 2.6 years of tap dance training) were submitted to the following procedures: (a) graded exercise test (GXT) on a treadmill until volitional exhaustion with 0.8 km.h of increment at each 3 and 1 minute of interval between stages and (b) tap dance choreography (TAP)-"The Shim Sham Shimmy"-consisting of 9 stages of 3 minutes with 1-minute rest between stages. Expired gas analyses were performed in all experimental sessions, providing breath-by-breath values for respiratory exchange rate (RER), oxygen uptake (VO(2)), and carbon dioxide production (CO2). Heart rate (HR) and rate of perceived exertion (RPE) were also measured. During the rest period between stages, blood samples (25 microl) were collected from the ear lobe for lactate threshold (LT) determination. It was observed that at the end of the TAP, subjects achieved an average of 83.8 +/- 6.2% of the HRmax and 68.9 +/- 11.3% of the VO(2)max, both previously identified in the GXT. The choreography demanded 204.7 +/- 31.3 kcal, an average RER of 0.88 +/- 0.05 and mean RPE of 13 +/- 2. The VO(2), HR, and RPE values did not significantly differ from those at the LT intensity identified during the GTX. Based on the present results, it was concluded that the TAP performance in the "The Shim Sham Shimmy" choreography elicited acute physiologic responses similar to those observed at the LT intensity, thus suggesting that Tap Dance constitutes a useful exercise modality for aerobic fitness and cardiovascular health improvements.

  20. Normal Caloric Responses during Acute Phase of Vestibular Neuritis

    PubMed Central

    Lee, Sun-Uk; Park, Seong-Ho; Kim, Hyo-Jung; Koo, Ja-Won

    2016-01-01

    Background and Purpose We report a novel finding of caloric conversion from normal responses into unilateral paresis during the acute phase of vestibular neuritis (VN). Methods We recruited 893 patients with a diagnosis of VN at Dizziness Clinic of Seoul National University Bundang Hospital from 2003 to 2014 after excluding 28 patients with isolated inferior divisional VN (n=14) and those without follow-up tests despite normal caloric responses initially (n=14). We retrospectively analyzed the neurotological findings in four (0.5%) of the patients who showed a conversion from initially normal caloric responses into unilateral paresis during the acute phase. Results In those four patients, the initial caloric tests were performed within 2 days of symptom onset, and conversion into unilateral caloric paresis was documented 1–4 days later. The clinical and laboratory findings during the initial evaluation were consistent with VN in all four patients except for normal findings in bedside head impulse tests in one of them. Conclusions Normal findings in caloric tests should be interpreted with caution during the acute phase of suspected VN. Follow-up evaluation should be considered when the findings of the initial caloric test are normal, but VN remains the most plausible diagnosis. PMID:26932259

  1. Involvement of the TRPV1 channel in the modulation of spontaneous locomotor activity, physical performance and physical exercise-induced physiological responses.

    PubMed

    Hudson, A S R; Kunstetter, A C; Damasceno, W C; Wanner, S P

    2016-01-01

    Physical exercise triggers coordinated physiological responses to meet the augmented metabolic demand of contracting muscles. To provide adequate responses, the brain must receive sensory information about the physiological status of peripheral tissues and organs, such as changes in osmolality, temperature and pH. Most of the receptors involved in these afferent pathways express ion channels, including transient receptor potential (TRP) channels, which are usually activated by more than one type of stimulus and are therefore considered polymodal receptors. Among these TRP channels, the TRPV1 channel (transient receptor potential vanilloid type 1 or capsaicin receptor) has well-documented functions in the modulation of pain sensation and thermoregulatory responses. However, the TRPV1 channel is also expressed in non-neural tissues, suggesting that this channel may perform a broad range of functions. In this review, we first present a brief overview of the available tools for studying the physiological roles of the TRPV1 channel. Then, we present the relationship between the TRPV1 channel and spontaneous locomotor activity, physical performance, and modulation of several physiological responses, including water and electrolyte balance, muscle hypertrophy, and metabolic, cardiovascular, gastrointestinal, and inflammatory responses. Altogether, the data presented herein indicate that the TPRV1 channel modulates many physiological functions other than nociception and thermoregulation. In addition, these data open new possibilities for investigating the role of this channel in the acute effects induced by a single bout of physical exercise and in the chronic effects induced by physical training.

  2. Involvement of the TRPV1 channel in the modulation of spontaneous locomotor activity, physical performance and physical exercise-induced physiological responses

    PubMed Central

    Hudson, A.S.R.; Kunstetter, A.C.; Damasceno, W.C.; Wanner, S.P.

    2016-01-01

    Physical exercise triggers coordinated physiological responses to meet the augmented metabolic demand of contracting muscles. To provide adequate responses, the brain must receive sensory information about the physiological status of peripheral tissues and organs, such as changes in osmolality, temperature and pH. Most of the receptors involved in these afferent pathways express ion channels, including transient receptor potential (TRP) channels, which are usually activated by more than one type of stimulus and are therefore considered polymodal receptors. Among these TRP channels, the TRPV1 channel (transient receptor potential vanilloid type 1 or capsaicin receptor) has well-documented functions in the modulation of pain sensation and thermoregulatory responses. However, the TRPV1 channel is also expressed in non-neural tissues, suggesting that this channel may perform a broad range of functions. In this review, we first present a brief overview of the available tools for studying the physiological roles of the TRPV1 channel. Then, we present the relationship between the TRPV1 channel and spontaneous locomotor activity, physical performance, and modulation of several physiological responses, including water and electrolyte balance, muscle hypertrophy, and metabolic, cardiovascular, gastrointestinal, and inflammatory responses. Altogether, the data presented herein indicate that the TPRV1 channel modulates many physiological functions other than nociception and thermoregulation. In addition, these data open new possibilities for investigating the role of this channel in the acute effects induced by a single bout of physical exercise and in the chronic effects induced by physical training. PMID:27191606

  3. Physiological responses of two soybean cultivars to cadmium

    SciTech Connect

    Marchiol, L.; Leita, L.; Martin, M.; Peressotti, A.

    1996-05-01

    Anthropogenic activities are increasing cadmium (Cd) concentrations in soils. Cadmium can be absorbed by plant roots and modify the physiology of the plant. Carbon exchange rate (CER) and leaf of two soybean (Glycine max [L.]Merr.) cultivars (Illini insensitive and Richland sensitive) for 6 consecutive days; Cd(NO{sub 3}){sub 2} was added to the hydroponic solution to achieve a final concentration of 50 {mu}mol. At the end of the experiment, stomata length and width, mesophyll limitation to photosynthesis, root hydraulic conductance, relative water content (RWC), and Cd concentration in leaves, stems, and roots were measured on treated and control plants. Cadmium progressively reduced CER and g{sub s} to about 50% after 6 d of treatment. This was more evident in Richland than in Illini and was not linked with leaf RWC and mesophyll limitation to photosynthesis. After 6 d, the apparent root hydraulic water conductivity was 67% lower in the Cd-treated plants than in controls. The primary mechanism affected by Cd-induced stress in soybean is root water uptake, and this reduction is consistent with the decrease in stomatal opening and conductance, and therefore, in photosynthesis. 20 refs., 3 figs., 2 tabs.

  4. Physiological responses to kayaking with a swivel seat.

    PubMed

    Michael, J S; Smith, R; Rooney, K

    2010-08-01

    The present study compared the physiological characteristics of flat-water kayaking utilising two seat conditions, the traditional fixed seat and novel swivel seat on an air-braked kayak simulator. The testing protocol included a submaximal warm up and one maximal ergometer paddling test. Ten elite kayakers (age 25+/-6 years, body mass 84.9+/-5.8 kg) were randomised to perform the testing protocol twice, once on each seat. During the testing protocol, expired air, heart rate (HR) and power output (PO) were continuously measured and gross efficiency (GE (kayak)) was calculated. Lactate (La) was recorded at the conclusion of each test. Repeated measures ANOVA indicated that paddling with the swivel seat generated significantly greater mean PO over the two-minute race duration compared to the fixed seat (299.1+/-24.9W and 279.8+/-19.2W respectively; p<0.05). This equated to a 6.5% increase in PO. A similar (6.9%) but non-significant difference in efficiency was generated as there was no significant difference recorded in the metabolic load over the two-minute ergometer test. No significant differences were present in any other variable measured. This greater PO generated with a swivel seat may be a significant advantage during on-water competition if the results from present ergometer test transfer.

  5. Physiological responses and energy expenditure during competitive fencing.

    PubMed

    Milia, Raffaele; Roberto, Silvana; Pinna, Marco; Palazzolo, Girolamo; Sanna, Irene; Omeri, Massimo; Piredda, Simone; Migliaccio, Gianmario; Concu, Alberto; Crisafulli, Antonio

    2014-03-01

    Fencing is an Olympic sport in which athletes fight one against one using bladed weapons. Contests consist of three 3-min bouts, with rest intervals of 1 min between them. No studies investigating oxygen uptake and energetic demand during fencing competitions exist, thus energetic expenditure and demand in this sport remain speculative. The aim of this study was to understand the physiological capacities underlying fencing performance. Aerobic energy expenditure and the recruitment of lactic anaerobic metabolism were determined in 15 athletes (2 females and 13 males) during a simulation of fencing by using a portable gas analyzer (MedGraphics VO2000), which was able to provide data on oxygen uptake, carbon dioxide production and heart rate. Blood lactate was assessed by means of a portable lactate analyzer. Average group energetic expenditure during the simulation was (mean ± SD) 10.24 ± 0.65 kcal·min(-1), corresponding to 8.6 ± 0.54 METs. Oxygen uptakeand heart rate were always below the level of anaerobic threshold previously assessed during the preliminary incremental test, while blood lactate reached its maximum value of 6.9 ± 2.1 mmol·L(-1) during the final recovery minute between rounds. Present data suggest that physical demand in fencing is moderate for skilled fencers and that both aerobic energy metabolism and anaerobic lactic energy sources are moderately recruited. This should be considered by coaches when preparing training programs for athletes.

  6. Physiological responses of Kosteletzkya virginica to coastal wetland soil.

    PubMed

    Wang, Hongyan; Tang, Xiaoli; Wang, Honglei; Shao, Hongbo

    2015-01-01

    Effects of salinity on growth and physiological indices of Kosteletzkya virginica seedlings were studied. Plant height, fresh weight (FW), dry weight (DW), and net photosynthetic rate (Pn) increased at 100 mM NaCl and slightly declined at 200 mM, but higher salinity induced a significant reduction. Chlorophyll content, stomatal conductance (Gs), intercellular CO2 concentration (Ci), and transpiration rate (E) were not affected under moderate salinities, while markedly decreased at severe salinities except for the increased Ci at 400 mM NaCl. Furthermore, no significant differences of Fv/Fm and ΦPSII were found at lower than 200 mM NaCl, whereas higher salinity caused the declines of Fv/Fm, ΦPSII, and qP similar to Pn, accompanied with higher NPQ. Besides, salt stress reduced the leaf RWC, but caused the accumulation of proline to alleviate osmotic pressure. The increased activities of antioxidant enzymes maintained the normal levels of MDA and relative membrane permeability. To sum up, Kosteletzkya virginica seedlings have good salt tolerance and this may be partly attributed to its osmotic regulation and antioxidant capacity which help to maintain water balance and normal ROS level to ensure the efficient photosynthesis. These results provided important implications for Kosteletzkya virginica acting as a promising multiuse species for reclaiming coastal soil.

  7. Physiological responses of Yellowstone bison to winter nutritional deprivation

    USGS Publications Warehouse

    DelGiudice, Glenn D.; Singer, Francis J.; Seal, Ulysses S.; Bowser, Gillian

    1994-01-01

    Because nutrition is critically related to other aspects of bison (Bison bison) ecology, and the winter ranges inhabited by bison in Yellowstone National Park (YNP) are ecologically diverse, it was important to determine if nutritional deprivation differences occurred among winter ranges. We used chemistry profiles of urine suspended in snow to compare nutritional deprivation of bison from January to April 1988 on 4 sampling areas of 3 winter ranges in YNP. Declining (P < 0.001) trends of urinary potassium: creatinine ratios in bison on all 4 sampling areas indicated progressive nutritional deprivation through late March. Concurrent increases (P ≤ 0.001) in mean urea nitrogen: creatinine ratios from late February through late march in 3 of 4 areas suggested that increased net catabolism was occurring. Diminished creatinine ratios of sodium and phosphorus reflected low dietary intake of these minerals throughout winter. Mean values and trends of urinary characteristics indicated nutritional deprivation varied among 3 winter ranges in YNP. Continued physiological monitoring of nutritional deprivation, along with detailed examination of other aspects of the bison's ecology, will provide greater insight into the role of ungulate nutrition in the dynamics of such a complex system and improve management.

  8. Physiological Responses of Kosteletzkya virginica to Coastal Wetland Soil

    PubMed Central

    Wang, Hongyan; Tang, Xiaoli; Wang, Honglei; Shao, Hongbo

    2015-01-01

    Effects of salinity on growth and physiological indices of Kosteletzkya virginica seedlings were studied. Plant height, fresh weight (FW), dry weight (DW), and net photosynthetic rate (Pn) increased at 100 mM NaCl and slightly declined at 200 mM, but higher salinity induced a significant reduction. Chlorophyll content, stomatal conductance (Gs), intercellular CO2 concentration (Ci), and transpiration rate (E) were not affected under moderate salinities, while markedly decreased at severe salinities except for the increased Ci at 400 mM NaCl. Furthermore, no significant differences of Fv/Fm and ΦPSII were found at lower than 200 mM NaCl, whereas higher salinity caused the declines of Fv/Fm, ΦPSII, and qP similar to Pn, accompanied with higher NPQ. Besides, salt stress reduced the leaf RWC, but caused the accumulation of proline to alleviate osmotic pressure. The increased activities of antioxidant enzymes maintained the normal levels of MDA and relative membrane permeability. To sum up, Kosteletzkya virginica seedlings have good salt tolerance and this may be partly attributed to its osmotic regulation and antioxidant capacity which help to maintain water balance and normal ROS level to ensure the efficient photosynthesis. These results provided important implications for Kosteletzkya virginica acting as a promising multiuse species for reclaiming coastal soil. PMID:25853144

  9. Physiological responses during whole body suspension of adult rats

    NASA Technical Reports Server (NTRS)

    Steffen, J. M.; Fell, R. D.; Musacchia, X. J.

    1987-01-01

    The objective of this study was to characterize responses of adult rats to one and two weeks of whole body suspension. Body weights and food and water intakes were initially reduced during suspension, but, while intake of food and water returned to presuspension levels, body weight remained depressed. Diuresis was evident, but only during week two. Hindlimb muscle responses were differential, with the soleus exhibiting the greatest atrophy and the EDL a relative hypertrophy. These findings suggest that adult rats respond qualitatively in a manner similar to juveniles during suspension.

  10. Physiological responses and evaluation of effects of BMI, smoking and drinking in high altitude acclimatization: a cohort study in Chinese Han young males.

    PubMed

    Peng, Qian-Qian; Basang, Zhuoma; Cui, Chao-Ying; Li, Lei; Qian, Ji; Gesang, Quzhen; Yang, La; La, Zong; De, Yang; Dawa, Puchi; Qu, Ni; Suo, Qu; Dan, Zhen; Xiao, Duoji; Wang, Xiao-Feng; Jin, Li

    2013-01-01

    High altitude acclimatization is a series of physiological responses taking places when subjects go to altitude. Many factors could influence these processes, such as altitude, ascending speed and individual characteristics. In this study, based on a repeated measurement design of three sequential measurements at baseline, acute phase and chronic phase, we evaluated the effect of BMI, smoking and drinking on a number of physiological responses in high altitude acclimatization by using mixed model and partial least square path model on a sample of 755 Han Chinese young males. We found that subjects with higher BMI responses were reluctant to hypoxia. The effect of smoking was not significant at acute phase. But at chronic phase, red blood cell volume increased less while respiratory function increased more for smoking subjects compared with nonsmokers. For drinking subjects, red blood cell volume increased less than nondrinkers at both acute and chronic phases, while blood pressures increased more than nondrinkers at acute phase and respiratory function, red blood cell volume and oxygen saturation increased more than nondrinkers at chronic phase. The heavy and long-term effect of smoking, drinking and other factors in high altitude acclimatization needed to be further studied.

  11. Emotional Responses to Music: Experience, Expression, and Physiology

    ERIC Educational Resources Information Center

    Lundqvist, Lars-Olov; Carlsson, Fredrik; Hilmersson, Per; Juslin, Patrik N.

    2009-01-01

    A crucial issue in research on music and emotion is whether music evokes genuine emotional responses in listeners (the emotivist position) or whether listeners merely perceive emotions expressed by the music (the cognitivist position). To investigate this issue, we measured self-reported emotion, facial muscle activity, and autonomic activity in…

  12. Physiological Environment Induces Quick Response – Slow Exhaustion Reactions

    PubMed Central

    Hiroi, Noriko; Lu, James; Iba, Keisuke; Tabira, Akito; Yamashita, Shuji; Okada, Yasunori; Flamm, Christoph; Oka, Kotaro; Köhler, Gottfried; Funahashi, Akira

    2011-01-01

    In vivo environments are highly crowded and inhomogeneous, which may affect reaction processes in cells. In this study we examined the effects of intracellular crowding and an inhomogeneity on the behavior of in vivo reactions by calculating the spectral dimension (ds), which can be translated into the reaction rate function. We compared estimates of anomaly parameters obtained from fluorescence correlation spectroscopy (FCS) data with fractal dimensions derived from transmission electron microscopy (TEM) image analysis. FCS analysis indicated that the anomalous property was linked to physiological structure. Subsequent TEM analysis provided an in vivo illustration; soluble molecules likely percolate between intracellular clusters, which are constructed in a self-organizing manner. We estimated a cytoplasmic spectral dimension ds to be 1.39 ± 0.084. This result suggests that in vivo reactions initially run faster than the same reactions in a homogeneous space; this conclusion is consistent with the anomalous character indicated by FCS analysis. We further showed that these results were compatible with our Monte-Carlo simulation in which the anomalous behavior of mobile molecules correlates with the intracellular environment, leading to description as a percolation cluster, as demonstrated using TEM analysis. We confirmed by the simulation that the above-mentioned in vivo like properties are different from those of homogeneously concentrated environments. Additionally, simulation results indicated that crowding level of an environment might affect diffusion rate of reactant. Such knowledge of the spatial information enables us to construct realistic models for in vivo diffusion and reaction systems. PMID:21960972

  13. Physiological response of largemouth bass to angling stress

    USGS Publications Warehouse

    Gustaveson, A. Wayne; Wydoski, Richard S.; Wedemeyer, Gary A.

    1991-01-01

    The physiological effects of catch-and-release fishing on largemouth bass Micropterus salmoides from Lake Powell and Mantua Reservoir, Utah, were evaluated, and an estimate of the time needed for recovery from hooking stress was obtained. Fatigue in Lake Powell fish, as indicated by elevated blood lactate, was directly proportional to hooking time (1–5 min) and water temperature, but recovery from the hyperlacticemia was relatively rapid (about 24 h). Hyperglycemia, an indicator of stress hormone production, did not occur in largemouth bass hooked and played for 1–5 min in the coldest water (11–13°C), was moderate in fish hooked and played at l6–20°C, and was severe in fish played for 5 min at 28–30°C. Fish held for recovery in live cages suffered further hyperglycemia, presumably because of the stress of confinement. Ionoregulation, as indicated by relatively stable plasma chloride values, was not immediately affected in largemouth bass caught at water temperatures of 11–13°C or 28–30°C, but an unusual hyperchloremia developed in fish hooked and played at 16–20°C. During recovery, the expected progressive hypochloremia developed. Plasma osmolality was somewhat affected by hooking at all water temperatures tested, but recovery was almost complete within about 8 h. Mantua Reservoir fish were hooked and played only at water temperatures of 23–26°C. The hyperlacticemia and hyperglycemia that occurred were generally more severe than in the Lake Powell fish hooked and played at either 16–20°C or 28–30°C. However, effects on plasma chloride and osmolality were similar to those occurring in Lake Powell fish.

  14. The physiologic response of domestic animals to ionizing radiation: a review.

    PubMed

    von Zallinger, C; Tempel, K

    1998-01-01

    With respect to clinical signs of the radiation syndromes, some remarkable species variations exist. For example the marked delayed reaction of the acute hematologic response in cows. An unusually high sensitivity of the central nervous system is found in burros, which is probably caused by acute vascular and/or metabolic changes in the brain. The species-specific number of intestinal crypt and hemopoietic stem cells may explain the early survival differences among species after high doses of irradiation. Mortality due to acute radiation syndromes is lowest in chickens. Regarding late effects, various neoplasms are typical in dogs, and cattle more commonly develop cataracts.

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

    PubMed Central

    Karoly, Hollis C.; Stevens, Courtney J.; Magnan, Renee E.; Harlaar, Nicole; Hutchison, Kent E.; Bryan, Angela D.

    2012-01-01

    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. PMID:22899923

  16. Thermoregulatory responses in exercising rats: methodological aspects and relevance to human physiology.

    PubMed

    Wanner, Samuel Penna; Prímola-Gomes, Thales Nicolau; Pires, Washington; Guimarães, Juliana Bohnen; Hudson, Alexandre Sérvulo Ribeiro; Kunstetter, Ana Cançado; Fonseca, Cletiana Gonçalves; Drummond, Lucas Rios; Damasceno, William Coutinho; Teixeira-Coelho, Francisco

    2015-01-01

    Rats are used worldwide in experiments that aim to investigate the physiological responses induced by a physical exercise session. Changes in body temperature regulation, which may affect both the performance and the health of exercising rats, are evident among these physiological responses. Despite the universal use of rats in biomedical research involving exercise, investigators often overlook important methodological issues that hamper the accurate measurement of clear thermoregulatory responses. Moreover, much debate exists regarding whether the outcome of rat experiments can be extrapolated to human physiology, including thermal physiology. Herein, we described the impact of different exercise intensities, durations and protocols and environmental conditions on running-induced thermoregulatory changes. We focused on treadmill running because this type of exercise allows for precise control of the exercise intensity and the measurement of autonomic thermoeffectors associated with heat production and loss. Some methodological issues regarding rat experiments, such as the sites for body temperature measurements and the time of day at which experiments are performed, were also discussed. In addition, we analyzed the influence of a high body surface area-to-mass ratio and limited evaporative cooling on the exercise-induced thermoregulatory responses of running rats and then compared these responses in rats to those observed in humans. Collectively, the data presented in this review represent a reference source for investigators interested in studying exercise thermoregulation in rats. In addition, the present data indicate that the thermoregulatory responses of exercising rats can be extrapolated, with some important limitations, to human thermal physiology.

  17. Thermoregulatory responses in exercising rats: methodological aspects and relevance to human physiology

    PubMed Central

    Wanner, Samuel Penna; Prímola-Gomes, Thales Nicolau; Pires, Washington; Guimarães, Juliana Bohnen; Hudson, Alexandre Sérvulo Ribeiro; Kunstetter, Ana Cançado; Fonseca, Cletiana Gonçalves; Drummond, Lucas Rios; Damasceno, William Coutinho; Teixeira-Coelho, Francisco

    2015-01-01

    Rats are used worldwide in experiments that aim to investigate the physiological responses induced by a physical exercise session. Changes in body temperature regulation, which may affect both the performance and the health of exercising rats, are evident among these physiological responses. Despite the universal use of rats in biomedical research involving exercise, investigators often overlook important methodological issues that hamper the accurate measurement of clear thermoregulatory responses. Moreover, much debate exists regarding whether the outcome of rat experiments can be extrapolated to human physiology, including thermal physiology. Herein, we described the impact of different exercise intensities, durations and protocols and environmental conditions on running-induced thermoregulatory changes. We focused on treadmill running because this type of exercise allows for precise control of the exercise intensity and the measurement of autonomic thermoeffectors associated with heat production and loss. Some methodological issues regarding rat experiments, such as the sites for body temperature measurements and the time of day at which experiments are performed, were also discussed. In addition, we analyzed the influence of a high body surface area-to-mass ratio and limited evaporative cooling on the exercise-induced thermoregulatory responses of running rats and then compared these responses in rats to those observed in humans. Collectively, the data presented in this review represent a reference source for investigators interested in studying exercise thermoregulation in rats. In addition, the present data indicate that the thermoregulatory responses of exercising rats can be extrapolated, with some important limitations, to human thermal physiology. PMID:27227066

  18. Physiological response of BSC phototrophic community to EPS removal

    NASA Astrophysics Data System (ADS)

    Adessi, Alessandra; Cruz de Carvalho, Ricardo; Silvestre, Susana; Rossi, Federico; Mugnai, Gianmarco; Marques da Silva, Jorge; Branquinho, Cristina; De Philippis, Roberto

    2015-04-01

    Biological Soil Crusts (BSCs) are associations between soil particles and varying proportions of cyanobacteria, heterotrophic bacteria, algae, fungi, lichens and mosses. BSCs play a major role in soil stabilization, and in drylands have been well acknowledged for mitigating desertification effects. Amongst the wide diversity of organisms that compose BSCs, cyanobacteria are the first primary producers: they colonize nutrient-limited soils, modifying the micro-environment through the excretion of large amounts of extracellular polymeric substances (EPSs). EPSs represent a huge carbon and nitrogen source for other inhabitants of the crust, are three-dimensionally spread through the first millimeters of the soil, and have a recognized role in influencing the hydrological behavior of the crust. The aim of this study was to investigate the possible role that EPSs play in the physiology of the phototrophic community residing on a light crust (without mosses or lichens, thus mainly inhabited by cyanobacteria and algae). In particular it was investigated whether the three-dimensional matrix in which EPSs are organized allowed light distribution and diffusion inside the crust, thus influencing photosynthesis. Non-invasive techniques were used to extract the polymeric matrix and to analyze photosynthetic performances in native and extracted BSC samples. Preliminary results suggested that the mild extraction protocol allowed to remove a portion of the matrix, and that this treatment revealed highly significant differences in the optical properties of the crusts comparing native and extracted samples. The extraction did not affect cell viability, as samples after the extraction were still photosynthetically active. However, chlorophyll variable fluorescence was significantly lower in the extracted samples than in native ones, and susceptibility to photoinhibition was significantly modified. Evaluating the role of the EPSs in the community is essential to further understand the

  19. Comprehensive physiological cardiovascular model enables automatic correction of hemodynamics in patients with acute life-threatening heart failure.

    PubMed

    Uemura, Kazunori; Kamiya, Atsunori; Shimizu, Shuji; Shishido, Toshiaki; Sugimachi, Masaru; Sunagawa, Kenji

    2006-01-01

    Saving life of patients with acute life-threatening heart failure is a major challenge. One has to correct several fatal hemodynamic abnormalities at the same time within a limited time frame. The formulation of such complicated treatments enables the development of a system that can be used to save automatically lives of patients with acute heart failure, an autopilot system. To accomplish this, we established a comprehensive physiological cardiovascular model, on which we based the design of the autopilot system. By translating hemodynamics into cardiovascular parameters (pumping ability, vascular resistance, blood volume), and by controlling each of these with individual drugs, we were able to correct blood pressure, cardiac output, and left atrial pressure to the target values rapidly (5.2 +/- 6.6, 6.8 +/- 4.6, and 11.7 +/- 9.8 minutes), stably, and simultaneously.

  20. Predicting response to antimicrobial therapy in children with acute sinusitis

    PubMed Central

    Shaikh, Nader; Wald, Ellen R.; Jeong, Jong H.; Kurs-Lasky, Marcia; Bowen, A’Delbert; Flom, Lynda L.; Hoberman, Alejandro

    2014-01-01

    Objective To determine prognostic factors that independently predict response to antimicrobial therapy in children with acute sinusitis. Study design 206 children meeting a priori clinical criteria for acute sinusitis who were given antimicrobial therapy by their primary care provider were included. The severity of symptoms in the 8 to 12 days after treatment was initiated was followed using a validated scale. We examined the univariate and multivariate association between factors present at the time of diagnosis (symptoms, signs, nasopharyngeal culture result, radiograph results) and time to resolution of symptoms. This study was conducted 8 to 10 years after 7-valent pneumococcal conjugate vaccination was introduced, but before introduction of the 13-valent pneumococcal conjugate vaccination. Results Children with proven nasopharyngeal colonization with Streptococcus pneumoniae improved more rapidly (6.5 vs. 8.5 median days to symptom resolution) than those who were not colonized with S. pneumoniae. Age and radiograph findings did not predict time to symptom resolution. Conclusions In children with acute sinusitis, proven nasopharyngeal colonization with S. pneumoniae at presentation independently predicted time to symptom resolution. Future randomized, placebo-controlled trials could investigate the usefulness of testing for the presence of nasopharyngeal pathogens as a predictor of response to treatment. PMID:24367985

  1. Gastric acid response to acute exposure to hypergravity

    PubMed Central

    Yoon, Gun; Kim, Hyun-Soo

    2017-01-01

    The influence of environmental stressors on the pathogenesis of gastrointestinal disease has received increased awareness. Stress affects different physiological functions of the gastrointestinal tract, including gastric acid secretion and mucosal blood flow. Repeated exposures of rapid-onset, highly-sustained hypergravity cause severe physical stress in the pilot. Although the effects of exposure to hypergravity on cardiovascular and cerebral functions have been the subjects of numerous studies, crucial information regarding pathophysiological changes in the gastrointestinal tract following hypergravity exposure is lacking. In this study, we investigated the effects of acute exposure to hypergravity on gastric secretory activity and gastrin release. Male Sprague-Dawley rats were exposed to +10Gz three times for 3 min. Gastric juice and blood were collected. The volume and total acidity of gastric juice, and the plasma gastrin level was measured. Acute exposure to +10Gz significantly decreased the gastric juice parameters. The gastric juice volume and total acidity of hypergravity-exposed rats were 3.54 ± 0.32 mL/100 g and 84.90 ± 5.17 mEq/L, respectively, which were significantly lower than those of the nonexposed rats (4.62 ± 0.39 mL/100 g and 97.37 ± 5.42 mEq/L; P < 0.001 and P < 0.001, respectively). In contrast, plasma gastrin level was not significantly altered following hypergravity exposure. We demonstrated that acute exposure to hypergravity led to a significant decrease in the gastric juice volume and acidity but did not alter the plasma gastrin level. PMID:27992379

  2. Physiological responses to feeding, fasting and estivation for anurans.

    PubMed

    Secor, Stephen M

    2005-07-01

    Anuran estivation is characterized by long episodes of aphagia. To investigate whether estivating anurans downregulate intestinal performance as an adaptive mechanism to reduce energy expenditure, I compared the metabolic and intestinal responses to feeding, fasting and estivation among non-estivating and estivating species of the anuran families Bufonidae, Leptodactylidae and Ranidae. Standard metabolic rates of the estivating Bufo alvarius, Ceratophrys ornata and Pyxicephalus adspersus were significantly less than those of the non-estivating Bufo marinus, Leptodactylus pentadactylus and Rana catesbeiana. Whereas the digestion of rodent meals equaling 15% of anuran body mass generated significant metabolic responses for all species, specific dynamic action was significantly greater for the estivating species. For estivating species, feeding triggered more than a doubling of small intestinal mass and significant upregulation of intestinal nutrient transport rates, resulting in six- to tenfold increases in total intestinal nutrient uptake capacity. The postprandial intestinal responses of the non-estivating species were much more modest, averaging a 50% increase in small intestinal mass and 69% increase in uptake capacities. Following 1 month of laboratory-induced estivation, C. ornata and P. adspersus had further depressed metabolic rates by 20%, intestinal masses by 44%, and total intestinal uptake capacities by 60%. In a fashion similar to infrequently feeding, sit-and-wait foraging snakes, estivating anurans possess the capacity to severely downregulate intestinal performance with fasting and estivation, and subsequently upregulate the gut with feeding. The depression in gut performance during estivation aids in reducing energy expenditure, thereby increasing the duration that the animal can remain dormant while relying solely upon stored energy.

  3. Cardiovascular responses to glucagon - Physiologic measurement by external recordings.

    NASA Technical Reports Server (NTRS)

    Byrne, M. J.; Pigott, V.; Spodick, D. H.

    1972-01-01

    Assessment by noninvasive polygraphic techniques of the cardiovascular responses of normal subjects to intravenous injections of glucagon and glucagon diluent. A blinding procedure which eliminated observer bias was used during the reading of tracings. Analysis of group results showed that glucagon provoked uniformly significant changes, including increase in heart rate, blood pressure, pressure-rate product, and ejection time index, and decrease in prejection period, mechanical and electromechanical systole, left ventricular ejection time, and the ratio PEP/LVET. The principal results correlated well with those of previous studies of the hemodynamic effects of glucagon.

  4. Aviator Psychological and Physiological Responses to Replacement Air Group Training.

    DTIC Science & Technology

    1979-01-01

    Pro.rm The [RAG syllabus for F-4 jet aircraft at the Niar ar aval Air StAtion, San Diego, California, is divided into several phases. A co-,trol day...sunming the various responses to the adjectives in the scale. Perceived Stress Measure Following completion of the RAG syllabus , each trainee... the Naval Medical Research and Development Comn;and, Department of the Navy, under research work unit ZF5!..524.002,5OO. The views presented in this

  5. Effects of acute hypoxia on cerebrovascular responses to carbon dioxide.

    PubMed

    Ogoh, Shigehiko; Nakahara, Hidehiro; Ueda, Shinya; Okazaki, Kazunobu; Shibasaki, Manabu; Subudhi, Andrew W; Miyamoto, Tadayoshi

    2014-06-01

    In normoxic conditions, a reduction in arterial carbon dioxide tension causes cerebral vasoconstriction, thereby reducing cerebral blood flow and modifying dynamic cerebral autoregulation (dCA). It is unclear to what extent these effects are altered by acute hypoxia and the associated hypoxic ventilatory response (respiratory chemoreflex). This study tested the hypothesis that acute hypoxia attenuates arterial CO2 tension-mediated regulation of cerebral blood flow to help maintain cerebral O2 homeostasis. Eight subjects performed three randomly assigned respiratory interventions following a resting baseline period, as follows: (1) normoxia (21% O2); (2) hypoxia (12% O2); and (3) hypoxia with wilful restraint of the respiratory chemoreflex. During each intervention, 0, 2.0, 3.5 or 5.0% CO2 was sequentially added (8 min stages) to inspired gas mixtures to assess changes in steady-state cerebrovascular CO2 reactivity and dCA. During normoxia, the addition of CO2 increased internal carotid artery blood flow and middle cerebral artery mean blood velocity (MCA Vmean), while reducing dCA (change in phase = -0.73 ± 0.22 rad, P = 0.005). During acute hypoxia, internal carotid artery blood flow and MCA Vmean remained unchanged, but cerebrovascular CO2 reactivity (internal carotid artery, P = 0.003; MCA Vmean, P = 0.031) and CO2-mediated effects on dCA (P = 0.008) were attenuated. The effects of hypoxia were not further altered when the respiratory chemoreflex was restrained. These findings support the hypothesis that arterial CO2 tension-mediated effects on the cerebral vasculature are reduced during acute hypoxia. These effects could limit the degree of hypocapnic vasoconstriction and may help to regulate cerebral blood flow and cerebral O2 homeostasis during acute periods of hypoxia.

  6. Excluded and behaving unethically: social exclusion, physiological responses, and unethical behavior.

    PubMed

    Kouchaki, Maryam; Wareham, Justin

    2015-03-01

    Across 2 studies, we investigated the ethical consequences of physiological responses to social exclusion. In Study 1, participants who were socially excluded were more likely to engage in unethical behavior to make money and the level of physiological arousal experienced during exclusion--measured using galvanic skin response--mediated the effects of exclusion on unethical behavior. Likewise, in Study 2, results from a sample of supervisor-subordinate dyads revealed a positive relationship between experience of workplace ostracism and unethical behaviors as rated by the immediate supervisors. This relationship was mediated by employees' reports of experienced physiological arousal. Together, the results of these studies demonstrate that physiological arousal accompanies social exclusion and provides an explanatory mechanism for the increased unethical behavior in both samples. Theoretical implications of these findings for research on ethical behavior and social exclusion in the workplace are discussed.

  7. Student Response (Clicker) Systems: Preferences of Biomedical Physiology Students in Asian Classes

    ERIC Educational Resources Information Center

    Hwang, Isabel; Wong, Kevin; Lam, Shun Leung; Lam, Paul

    2015-01-01

    Student response systems (commonly called "clickers") are valuable tools for engaging students in classroom interactions. In this study, we investigated the use of two types of response systems (a traditional clicker and a mobile device) by students in human physiology courses. Our results showed high student satisfaction with the use of…

  8. Physiological-Cognitive-Emotional Responses to Defense-Arousing Communication: Overview and Sex Differences.

    ERIC Educational Resources Information Center

    Gordon, Ronald D.

    A 328-item checklist, suitable for the self-reporting of responses to any stimulus event, was administered to 107 upper division college students in an attempt to investigate the physiological-cognitive-emotional responses to defense arousing communication and to discover a greater range of the key features of the phenomena of…

  9. "A Frog in My Kneecap": Children's Perceived Physiological Responses to Stresses.

    ERIC Educational Resources Information Center

    Shields, Stephanie A.

    This paper describes a study designed to provide information regarding children's perceptions of their own physiological responses associated with feelings of apprehension. A second goal was to compare children's self reports with their reports on parent emotional responses and also with parents' reports on their own stress-related physiological…

  10. Study of physiological and behavioral response to transitions between rotating and nonrotating environments

    NASA Technical Reports Server (NTRS)

    Brady, J. F.

    1972-01-01

    Future manned space missions may require transition between artificial gravity and weightlessness environments. The frequency and rate of such transition will influence the psychophysiological responses of man. Abrupt transfers are examined between such rotating and nonrotating environments to determine the physiological and behavioral responses of man. Five subjects were tested using rates of rotation up to 5 rpm.

  11. Physiological Response of Plants to Temporary Changes in Gravity Conditions

    NASA Astrophysics Data System (ADS)

    Pandolfi, Camilla; Mugnai, Sergio; Masi, Elisa; Azzarello, Elisa; Voigt, Boris; Baluska, Frantisek; Volkmann, Dieter; Mancuso, Stefano

    Gravity is the main factor that influences the direction of growth of plant organs, and has also a direct effect on the plant metabolism. When an organ, mainly roots, is turned by between 0 (vertical) and 90 (horizontal), the change of orientation is perceived by its organs producing the so-called gravitropic reaction, which involves a strong metabolic response. In order to study these reaction in real microgravity conditions, some experiments have been set up during six ESA parabolic flight campaign. Oxygen concentration in the solution, in which roots of Zea mays were placed, have been constantly monitored during normal, hyper-and microgravity conditions. An evident burst in oxygen fluxes started just 2.0 0.5 s after the imposition of microgravity conditions. No significant changes were noticed neither in normal nor in hyper-gravity conditions. These measurements were done using oxymeters, that revealed the onset of long lasting oxygen bursts appearing only during microgravity. Although the chemical nature of these oxygen bursts is still unknown, they may implicate a strong generation of reactive oxygen species as they exactly match the microgravity situation. Thus, our data strongly sug-gest that the sensing mechanism is not related to a general mechano-stress, which was imposed also during hypergravity, but is very specific of the microgravity situation. Moreover, it is well-known that stress rapidly induces reactive oxygen bursts which are associated with oxygen influx and reactive oxygen efflux from stressed plant tissues. Accordingly, our data indicate that microgravity represents a stress situation for plants, especially for root apices, and these bursts, probably ROS, are initiating and integrating adaptive responses of plant roots which resemble other unrelated stress situations. To validate this hypothesis we added to our ex-perimental set-up two very sensitive selective microelectrodes for H2 O2 and NO, and, even if the parabolic flights are not

  12. Salivary Markers of Inflammation in Response to Acute Stress

    PubMed Central

    Slavish, Danica C.; Graham-Engeland, Jennifer E.; Smyth, Joshua M.; Engeland, Christopher G.

    2014-01-01

    There is burgeoning interest in the ability to detect inflammatory markers in response to stress within naturally occurring social contexts and/or across multiple time points per day within individuals. Salivary collection is a less invasive process than current methods of blood collection and enables intensive naturalistic methodologies, such as those involving extensive repeated measures per day over time. Yet the reliability and validity of saliva-based to blood-based inflammatory biomarkers in response to stress remains unclear. We review and synthesize the published studies that have examined salivary markers of inflammation following exposure to an acute laboratory stressor. Results from each study are reviewed by analyte (IL-1β, TNF-α, IL-6, IL-2, IL-4, IL-10, IL-12, CRP) and stress type (social-cognitive and exercise-physical), after which methodological issues and limitations are addressed. Although the literature is limited, several inflammatory markers (including IL-1β, TNF-α, and IL-6) have been reliably determined from saliva and have increased significantly in response to stress across multiple studies, with effect sizes ranging from very small to very large. Although CRP from saliva has been associated with CRP in circulating blood more consistently than other biomarkers have been associated with their counterparts in blood, evidence demonstrating it reliably responds to acute stress is absent. Although the current literature is presently too limited to allow broad assertion that inflammatory biomarkers determined from saliva are valuable for examining acute stress responses, this review suggests that specific targets may be valid and highlights specific areas of need for future research. PMID:25205395

  13. Molecular Structure of Physiologically-Responsive Hydrogels Controls Diffusive Behavior

    PubMed Central

    Carr, Daniel A.; Peppas, Nicholas A.

    2011-01-01

    Summary Polymeric networks and the ensuing hydrogels of methacrylic acid and N-vinyl pyrrolidone were successfully synthesized using a UV-initiated free radical polymerization and characterized to assess their applicability as carriers for directed drug delivery. FT-IR spectroscopy revealed shifts in peak absorbances that indicated the presence of hydrogen bonding complexes between functional groups, while SEM imaging showed that the different comonomers affect the surface morphology of the microparticles. Dynamic pH swelling studies demonstrated the pH responsiveness of the carriers in gastric and intestinal conditions and revealed that systems containing higher concentrations of methacrylic acid experienced the highest degree of hydrogen bonding complexation in gastric conditions. The presence of NVP in the systems enhanced swelling. Equilibrium swelling studies revealed that the mesh size was sufficiently large to allow drug diffusion across the networks. PMID:19016502

  14. Physiological responses of a rodent to heliox reveal constancy of evaporative water loss under perturbing environmental conditions.

    PubMed

    Cooper, Christine Elizabeth; Withers, Philip Carew

    2014-10-15

    Total evaporative water loss of endotherms is assumed to be determined essentially by biophysics, at least at temperatures below thermoneutrality, with evaporative water loss determined by the water vapor deficit between the animal and the ambient air. We present here evidence, based on the first measurements of evaporative water loss for a small mammal in heliox, that mammals may have a previously unappreciated ability to maintain acute constancy of total evaporative water loss under perturbing environmental conditions. Thermoregulatory responses of ash-grey mice (Pseudomys albocinereus) to heliox were as expected, with changes in metabolic rate, conductance, and respiratory ventilation consistent with maintaining constancy of body temperature under conditions of enhanced heat loss. However, evaporative water loss did not increase in heliox. This is despite our confirmation of the physical effect that heliox augments evaporation from nonliving surfaces, which should increase cutaneous water loss, and increases minute volume of live ash-grey mice in heliox to accommodate their elevated metabolic rate, which should increase respiratory water loss. Therefore, mice had not only a thermoregulatory but also a hygroregulatory response to heliox. We interpret these results as evidence that ash-grey mice can acutely control their evaporative water loss under perturbing environmental conditions and suggest that hygroregulation at and below thermoneutrality is an important aspect of the physiology of at least some small mammals.

  15. Physiological Responses to Exergaming After Spinal Cord Injury

    PubMed Central

    Burns, Patricia; Kressler, Jochen; Nash, Mark S.

    2012-01-01

    Purpose: To investigate whether exergaming satisfies guideline-based intensity standards for exercise conditioning (40%/50% oxygen uptake reserve [VO2R] or heart rate reserve (HRR), or 64%/70% of peak heart rate [HRpeak]) in persons with paraplegia. Methods: Nine men and women (18-65 years old) with chronic paraplegia (T1-L1, AIS A-C) underwent intensity-graded arm cycle exercise (AE) to evaluate VO2peak and HRpeak. On 2 randomized nonconsecutive days, participants underwent graded exercise using a custom arm cycle ergometer that controls the video display of a Nintendo Gamecube (GameCycle; Three Rivers Holdings LLC, Mesa, AZ) or 15 minutes of incrementally wrist-weighted tennis gameplay against a televised opponent (XaviX Tennis System; SSD Co Ltd, Kusatsu, Japan). Results: GameCycle exergaming (GCE) resistance settings ≥0.88 Nm evoked on average ≥50% VO2R. During XaviX Tennis System exergaming (XTSE) with wrist weights ≥2 lbs, average VO2 reached a plateau of ~40% VO2R. Measurements of HR were highly variable and reached average values ≥50% HRR during GCE at resistance settings ≥0.88 Nm. During XTSE, average HR did not reach threshold levels based on HRR for any wrist weight (20%-35% HRR). Conclusions: On average, intensity responses to GCE at resistance setting ≥0.88 Nm were sufficient to elicit exercise intensities needed to promote cardiorespiratory fitness in individuals with SCI. The ability of XTSE to elicit cardiorespiratory fitness benefits is most likely limited to individuals with very low fitness levels and may become subminimal with time if used as a conditioning stimulus. PMID:23459619

  16. Physiological responses to folate overproduction in Lactobacillus plantarum WCFS1

    PubMed Central

    2010-01-01

    Background Using a functional genomics approach we addressed the impact of folate overproduction on metabolite formation and gene expression in Lactobacillus plantarum WCFS1. We focused specifically on the mechanism that reduces growth rates in folate-overproducing cells. Results Metabolite formation and gene expression were determined in a folate-overproducing- and wild-type strain. Differential metabolomics analysis of intracellular metabolite pools indicated that the pool sizes of 18 metabolites differed significantly between these strains. The gene expression profile was determined for both strains in pH-regulated chemostat culture and batch culture. Apart from the expected overexpression of the 6 genes of the folate gene cluster, no other genes were found to be differentially expressed both in continuous and batch cultures. The discrepancy between the low transcriptome and metabolome response and the 25% growth rate reduction of the folate overproducing strain was further investigated. Folate production per se could be ruled out as a contributing factor, since in the absence of folate production the growth rate of the overproducer was also reduced by 25%. The higher metabolic costs for DNA and RNA biosynthesis in the folate overproducing strain were also ruled out. However, it was demonstrated that folate-specific mRNAs and proteins constitute 8% and 4% of the total mRNA and protein pool, respectively. Conclusion Folate overproduction leads to very little change in metabolite levels or overall transcript profile, while at the same time the growth rate is reduced drastically. This shows that Lactobacillus plantarum WCFS1 is unable to respond to this growth rate reduction, most likely because the growth-related transcripts and proteins are diluted by the enormous amount of gratuitous folate-related transcripts and proteins. PMID:21167023

  17. Growth, physiological and biochemical response of ponderosa pine pinus ponderosa' to ozone. Final report

    SciTech Connect

    Temple, P.J.; Bytnerowicz, A.

    1993-11-01

    In 1989 and 1990, the effects of multi-year ozone exposures on growth, foliar injury and physiological responses in ponderosa pine were examined. Two-year old seedlings were exposed to four ozone treatments in open-top chambers: clean air (subambient levels of oxidants and particles); ambient ozone; twice-ambient ozone; or ambient air. The study was performed at Shirley Meadow in the southern Sierra Nevada. In both years, ambient ozone levels were representative of other forests in the region. While ozone is the most phytotoxic air pollutant, seedlings also experienced elevated concentrations of nitric acid and ammonia. In 1990, ambient ozone significantly increased injury to previous year needles. Premature senescence and alterations in physiological responses were also noted. Exposure to twice-ambient ozone reduced seedling biomass, increased injury and caused decreases in a variety of physiological responses.

  18. Physiological and biochemical response to high temperature stress in Okra (Abelmoschus esculentus L. Moench)

    NASA Astrophysics Data System (ADS)

    Hayamanesh, Shahnoosh; Keitel, Claudia; Ahmad, Nabil; Trethowan, Richard

    2016-04-01

    High temperature has been shown to lower the growth and yield of Okra, an important summer vegetable crop grown in Asia, Africa, the Middle East and Australia. We aimed to characterise the physiological and biochemical response of Okra to heat stress. 150 genotypes from Pakistan and the AVRDC (The World Vegetable Centre) were screened for their physiological response (fluorescence, electrolyte leakage and yield) to heat in a greenhouse. Four genotypes (including heat tolerant and sensitive) were selected and subsequently grown in control and hot greenhouses. Daytime temperatures were on average 10°C warmer in the hot greenhouse, whereas nighttime temperatures were similar between the two temperature treatments. During a 12 week period, the physiological (assimilation rate, transpiration rate, stomatal conductance, fluorescence, electrolyte leakage, water potential) and biochemical (carbohydrates, sugar alcohols, C content) response of the four genotypes to heat stress was assessed. The effect of heat stress on the C allocation patterns and yield in Okra will be discussed.

  19. Sleep Disturbance and Older Adults' Inflammatory Responses to Acute Stress

    PubMed Central

    Heffner, Kathi L.; Ng, H. Mei; Suhr, Julie A.; France, Christopher R.; Marshall, Gailen D.; Pigeon, Wilfred R.; Moynihan, Jan A.

    2013-01-01

    Objectives Poor sleep diminishes mental and physical health. The objective of this study was to examine associations between sleep disturbance and interleukin-6 (IL-6) responses to acute mental stress in older adults. Design Observational study of community-dwelling, healthy older adults. Setting Participants completed the study in a clinical research laboratory of a mid-sized university. Participants Generally healthy, community-dwelling men and women 50 years of age and older. Measurements IL-6 and negative affect at rest and following a series of challenging cognitive tests; sleep quality; depressive symptoms; perceived stress; loneliness. Results Participants categorized as poor sleepers based on Pittsburgh Sleep Quality Index scores had significantly larger IL-6 responses to the cognitive stressors compared to good sleepers. The association between poor sleep and heightened IL-6 response to acute stress was not explained by other psychosocial factors previously linked to immune dysregulation, including depressive symptoms, perceived stress, and loneliness. Conclusions Findings add to the growing evidence for poor sleep as an independent risk factor for poor mental and physical health. Older adults may be particularly vulnerable to effects of sleep disturbance due to significant age-related changes in both sleep and inflammatory regulation. PMID:22327621

  20. Discrepancy among acute guideline levels for emergency response.

    PubMed

    Oberg, Mattias; Palmen, Nicole; Johanson, Gunnar

    2010-12-15

    Acute guidance values are tools for public health risk assessment and management during planning, preparedness and response related to sudden airborne release of hazardous chemicals. The two most frequently used values, i.e. Acute Exposure Guidance Levels (AEGL) and Emergency Response Planning Guideline (ERPG), were compared in qualitative and quantitative terms. There was no significant difference between the general level of AEGL and ERPG values, suggesting the two systems are equally precautious. However, the guidance values diverged by a factor of 3 or more for almost 40% of the substances, including many of high production volume. These deviations could be explained by differences in selection of critical effect or critical study and in a few cases differences in interpretation of the same critical study. Diverging guidance values may hamper proper risk communication and risk management. Key factors for broad international acceptance of harmonized values include transparency of the decision process, agreement on definition of toxicological tiers, and a target population including sensitive groups of the general population. In addition, development of purely health based values is encouraged. Risk management issues, such as land use and emergency response planning should be treated separately, as these rely on national legislation and considerations.

  1. Lymphocyte aromatic hydrocarbon responsiveness in acute leukemia of childhood

    SciTech Connect

    Blumer, J.L.; Dunn, R.; Esterhay, M.D.; Yamashita, T.S.; Gross, S.

    1981-12-01

    Aryl hydrocarbon hydroxylase (AHH) activity and inducibility were examined in mitogen-stimulated cultured lymphocytes from children with acute leukemia in remission, with nonleukemic malignancies, and with no family or personal history of malignant disease. Neither morphological differences nor differences in mitogen responsivelness were observed among the three sources of cells studied. Levels of constitutive and dibenzanthracene-induced AHH activity were found to be similar among the three groups by analysis of variance. However, when results were analyzed in terms of inducibility ratios, it was found that cells from leukemic children were significantly less inducible (p < 0.005) than cells from unaffected children or children with nonleukemic malignancies. The reason for this difference became apparent when statistical criteria were employed for the phenotypic separation of individuals who were highly aromatic hydrocarbon responsive and minimally responsive. A significantly larger proportion (p < 0.001) of leukemic children than unaffected children or children with nonleukemic malignancy were found to be minimally aromatic hydrocarbon responsive. Moreover, in patients with acute lymphoblastic leukemia relapsing while on therapy, longer durations of the first remission were correlated (r = 0.63, p < 0.05) with the highly inducible AHH phenotype.

  2. Physiological responses to swimming while wearing a wet suit.

    PubMed

    Trappe, T A; Pease, D L; Trappe, S W; Troup, J P; Burke, E R

    1996-02-01

    The purpose of this study was to examine the influence of three different wet suits on the oxygen uptake (VO(2)), minute ventilation (VE). and heart rate responses to front crawl swimming. Five male subjects swam at four velocities (0.90, 1.05, 1.18 +/- 0.01, 1.31 +/- 0.02 m.sec(-1)) in each of four swimming suit conditions in a swimming flume. Conditions were completed in random order using a conventional swimming suit (SS), a wet suit that covered the full body (FULL), a wet suit that left the arms exposed (LONG), and a wet suit that left the arms and lower legs exposed (SHORT). Water temperature was 26.5 +/- 1.0 degrees C for all trials. VO(2) and V(E) were decreased (p < 0.05) while swimming in the three wet suits as compared to the SS at all four velocities. VO(2) and V(E) were also lower (p < 0.05) in the FULL as compared to the SHORT at all four velocities; however, there were no differences between the SHORT and LONG or LONG and FULL at any of the velocities. Decreases in VO(2) from SS averaged 16.2 +/- 1.9 (SHORT), 22.8 +/- 2.4 (LONG), and 33.6 +/- 2.9% (FULL) over all four velocities. Similarly, reductions in V(E) from SS averaged 14.6+/- 1.5, 19.6 +/- 1.6, 24.2 +/- 1.5%, in the SHORT, LONG, and FULL, respectively. Heart rate and rating of perceived exertion were higher (p < 0.05) in the SS as compared to the three wet suits at 1.31 m.sec(-1) only. In conclusion, oxygen uptake and minute ventilation during swimming at a given velocity were decreased when wearing a wet suit as compared to a conventional swimming suit. Further, these decreases were related to the amount of wet suit covering the body.

  3. Acute phase protein response in the capybara (Hydrochoerus hydrochaeris).

    PubMed

    Bernal, Luis; Feser, Mariane; Martínez-Subiela, Silvia; García-Martínez, Juan D; Cerón, José J; Tecles, Fernando

    2011-10-01

    We evaluated the acute phase protein response in capybaras (Hydrochoerus hydrochaeris). Three animal groups were used: 1) healthy animals (n=30), 2) a group in which experimental inflammation with turpentine was induced (n=6), and 3) a group affected with sarcoptic scabies (n=14) in which 10 animals were treated with ivermectin. Haptoglobin (Hp), acid-soluble glycoprotein (ASG) and albumin were analyzed in all animals. In those treated with turpentine, Hp reached its maximum value at 2 wk with a 2.7-fold increase, whereas ASG increased 1.75-fold and albumin decreased 0.87-fold 1 wk after the induction of inflammation. Capybaras affected with sarcoptic scabies presented increases in Hp and ASG of 4.98- and 3.18-fold, respectively, and a 0.87-fold decrease in albumin, compared with healthy animals. Haptoglobin and ASG can be considered as moderate, positive acute phase proteins in capybaras because they showed less than 10-fold increases after an inflammatory process and reached their peak concentrations 1 wk after the induction of inflammation. Conversely, albumin can be considered a negative acute phase protein in capybaras because it showed a reduction in concentration after inflammatory stimulus.

  4. Summer and fall ants have different physiological responses to food macronutrient content.

    PubMed

    Cook, Steven C; Eubanks, Micky D; Gold, Roger E; Behmer, Spencer T

    2016-04-01

    Seasonally, long-lived animals exhibit changes in behavior and physiology in response to shifts in environmental conditions, including food abundance and nutritional quality. Ants are long-lived arthropods that, at the colony level, experience such seasonal shifts in their food resources. Previously we reported summer- and fall-collected ants practiced distinct food collection behavior and nutrient intake regulation strategies in response to variable food protein and carbohydrate content, despite being reared in the lab under identical environmental conditions and dietary regimes. Seasonally distinct responses were observed for both no-choice and choice dietary experiments. Using data from these same experiments, our objective here is to examine colony and individual-level physiological traits, colony mortality and growth, food processing, and worker lipid mass, and how these traits change in response to variable food protein-carbohydrate content. For both experiments we found that seasonality per se exerted strong effects on colony and individual level traits. Colonies collected in the summer maintained total worker mass despite high mortality. In contrast, colonies collected in the fall lived longer, and accumulated lipids, including when reared on protein-biased diets. Food macronutrient content had mainly transient effects on physiological responses. Extremes in food carbohydrate content however, elicited a compensatory response in summer worker ants, which processed more protein-biased foods and contained elevated lipid levels. Our study, combined with our previously published work, strongly suggests that underlying physiological phenotypes driving behaviors of summer and fall ants are likely fixed seasonally, and change circannually.

  5. Acute responses to exercise training and relationship with exercise adherence in moderate chronic obstructive pulmonary disease.

    PubMed

    Rizk, Amanda K; Wardini, Rima; Chan-Thim, Emilie; Bacon, Simon L; Lavoie, Kim L; Pepin, Véronique

    2015-11-01

    The objectives of our study were to (i) compare, in chronic obstructive pulmonary disease (COPD) patients, acute responses to continuous training at high intensity (CTHI), continuous training at ventilatory threshold (CTVT) and interval training (IT); (ii) examine associations between acute responses and 12-week adherence; and (iii) investigate whether the relationship between acute responses and adherence is mediated/moderated by affect/vigour. Thirty-five COPD patients (forced expiratory volume in 1 second = 60.2 ± 15.8% predicted), underwent baseline assessments, were randomly assigned to CTHI, CTVT or IT, were monitored throughout about before training, and underwent 12 weeks of exercise training during which adherence was tracked. Compared with CTHI, CTVT was associated with lower respiratory exchange ratio, heart rate and respiratory rate (RR), while IT induced higher [Formula: see text], [Formula: see text]maximal voluntary ventilation, RR and lower pulse oxygen saturation. From pre- to post-exercise, positive affect increased (F = 9.74, p < 0.001) and negative affect decreased (F = 6.43, p = 0.005) across groups. CTVT reported greater end-exercise vigour compared to CTHI (p = 0.01) and IT (p = 0.02). IT exhibited lowest post-exercise vigour (p = 0.04 versus CTHI, p = 0.02 versus CTVT) and adherence rate (F = 6.69, p = 0.004). Mean [Formula: see text] (r = -0.466, p = 0.007) and end-exercise vigour (r = 0.420, p = 0.017) were most strongly correlated with adherence. End-exercise vigour moderated the relationship between [Formula: see text] and adherence (β = 2.74, t(32) = 2.32, p = 0.03). In summary, CTHI, CTVT and IT improved affective valence from rest to post-exercise and induced a significant 12-week exercise training effect. However, they elicited different acute physiological responses, which in turn were associated with differences in 12-week adherence to the target training intensity. This association was moderated by acute end-exercise vigour.

  6. What can an ecophysiological approach tell us about the physiological responses of marine invertebrates to hypoxia?

    PubMed

    Spicer, John I

    2014-01-01

    Hypoxia (low O2) is a common and natural feature of many marine environments. However, human-induced hypoxia has been on the rise over the past half century and is now recognised as a major problem in the world's seas and oceans. Whilst we have information on how marine invertebrates respond physiologically to hypoxia in the laboratory, we still lack understanding of how they respond to such stress in the wild (now and in the future). Consequently, here the question 'what can an ecophysiological approach tell us about physiological responses of marine invertebrates to hypoxia' is addressed. How marine invertebrates work in the wild when challenged with hypoxia is explored using four case studies centred on different hypoxic environments. The recent integration of the various -omics into ecophysiology is discussed, and a number of advantages of, and challenges to, successful integration are suggested. The case studies and -omic/physiology integration data are used to inform the concluding part of the review, where it is suggested that physiological responses to hypoxia in the wild are not always the same as those predicted from laboratory experiments. This is due to behaviour in the wild modifying responses, and therefore more than one type of 'experimental' approach is essential to reliably determine the actual response. It is also suggested that assuming it is known what a measured response is 'for' can be misleading and that taking parodies of ecophysiology seriously may impede research progress. This review finishes with the suggestion that an -omics approach is, and is becoming, a powerful method of understanding the response of marine invertebrates to environmental hypoxia and may be an ideal way of studying hypoxic responses in the wild. Despite centring on physiological responses to hypoxia, the review hopefully serves as a contribution to the discussion of what (animal) ecophysiology looks like (or should look like) in the 21st century.

  7. The effects of acute alcohol exposure on the response properties of neurons in visual cortex area 17 of cats

    SciTech Connect

    Chen Bo; Xia Jing; Li Guangxing; Zhou Yifeng

    2010-03-15

    Physiological and behavioral studies have demonstrated that a number of visual functions such as visual acuity, contrast sensitivity, and motion perception can be impaired by acute alcohol exposure. The orientation- and direction-selective responses of cells in primary visual cortex are thought to participate in the perception of form and motion. To investigate how orientation selectivity and direction selectivity of neurons are influenced by acute alcohol exposure in vivo, we used the extracellular single-unit recording technique to examine the response properties of neurons in primary visual cortex (A17) of adult cats. We found that alcohol reduces spontaneous activity, visual evoked unit responses, the signal-to-noise ratio, and orientation selectivity of A17 cells. In addition, small but detectable changes in both the preferred orientation/direction and the bandwidth of the orientation tuning curve of strongly orientation-biased A17 cells were observed after acute alcohol administration. Our findings may provide physiological evidence for some alcohol-related deficits in visual function observed in behavioral studies.

  8. Baroreflex Responses to Acute Changes in Blood Volume in Humans

    NASA Technical Reports Server (NTRS)

    Thompson, Cynthia A.; Tatro, Dana L.; Ludwig, David A.; Convertino, Victor A.

    1990-01-01

    To test the hypothesis that acute changes in plasma volume affect the stimulus-response relations of high- and low- pressure baroreflexes, eight men (27-44 yr old) underwent measurements for carotid-cardiac and cardiopulmonary baro- reflex responses under the following three volemic conditions: hypovolemic, normovolemic, and hypervolemic. The stimulus- response relation of the carotid-cardiac response curve was generated using a neck cuff device, which delivered pressure changes between +40 and -65 mmHg in continuous steps of 15 mmHg. The stimulus-response relationships of the cardiopulmonary baroreflex were studied by measurements of Forearm Vascular Resistance (FVR) and Peripheral Venotis Pressure (PVP) during low levels of lower body negative pressure (O to -20 mmHg). Altered vascular volume had no effect on response relations of the carotid-cardiac baroreflex but did alter the gain of the cardiopulmonary baroreflex (-7.93 q 1.71, -4.36 q 1.38, and -2.56 q 1.59 peripheral resistance units/mmHg for hypovolemic, normovolemic, and hypervolemic, respectively) independent of shifts in baseline FVR and PVP. These results indicate greater demand for vasoconstriction for equal reductions in venous pressure during progressive hypovolemia; this condition may compromise the capacity to provide adequate peripheral resistance during severe orthostatic stress. Fluid loading before reentry after spaceflight may act to restore vasoconstrictive capacity of the cardiopulnionary baroreflex but may not be an effective countermeasure against potential post- flight impairment of the carotid-cardiac baroreflex.

  9. Physiological Responses to Salinity Vary with Proximity to the Ocean in a Coastal Amphibian.

    PubMed

    Hopkins, Gareth R; Brodie, Edmund D; Neuman-Lee, Lorin A; Mohammadi, Shabnam; Brusch, George A; Hopkins, Zoë M; French, Susannah S

    2016-01-01

    Freshwater organisms are increasingly exposed to elevated salinity in their habitats, presenting physiological challenges to homeostasis. Amphibians are particularly vulnerable to osmotic stress and yet are often subject to high salinity in a variety of inland and coastal environments around the world. Here, we examine the physiological responses to elevated salinity of rough-skinned newts (Taricha granulosa) inhabiting a coastal stream on the Pacific coast of North America and compare the physiological responses to salinity stress of newts living in close proximity to the ocean with those of newts living farther upstream. Although elevated salinity significantly affected the osmotic (body weight, plasma osmolality), stress (corticosterone), and immune (bactericidal ability) responses of newts, animals found closer to the ocean were generally less reactive to salt stress than those found farther upstream. Our results provide possible evidence for some physiological tolerance in this species to elevated salinity in coastal environments. As freshwater environments become increasingly saline and more stressful, understanding the physiological tolerances of vulnerable groups such as amphibians will become increasingly important to our understanding of their abilities to respond, to adapt, and, ultimately, to survive.

  10. Preservation of high glycolytic phenotype by establishing new acute lymphoblastic leukemia cell lines at physiologic oxygen concentration

    SciTech Connect

    Sheard, Michael A.; Ghent, Matthew V.; Cabral, Daniel J.; Lee, Joanne C.; Khankaldyyan, Vazgen; Ji, Lingyun; Wu, Samuel Q.; Kang, Min H.; and others

    2015-05-15

    Cancer cells typically exhibit increased glycolysis and decreased mitochondrial oxidative phosphorylation, and they continue to exhibit some elevation in glycolysis even under aerobic conditions. However, it is unclear whether cancer cell lines employ a high level of glycolysis comparable to that of the original cancers from which they were derived, even if their culture conditions are changed to physiologically relevant oxygen concentrations. From three childhood acute lymphoblastic leukemia (ALL) patients we established three new pairs of cell lines in both atmospheric (20%) and physiologic (bone marrow level, 5%) oxygen concentrations. Cell lines established in 20% oxygen exhibited lower proliferation, survival, expression of glycolysis genes, glucose consumption, and lactate production. Interestingly, the effects of oxygen concentration used during cell line initiation were only partially reversible when established cell cultures were switched from one oxygen concentration to another for eight weeks. These observations indicate that ALL cell lines established at atmospheric oxygen concentration can exhibit relatively low levels of glycolysis and these levels are semi-permanent, suggesting that physiologic oxygen concentrations may be needed from the time of cell line initiation to preserve the high level of glycolysis commonly exhibited by leukemias in vivo. - Highlights: • Establishing new ALL cell lines in 5% oxygen resulted in higher glycolytic expression and function. • Establishing new ALL cell lines in 5% oxygen resulted in higher proliferation and lower cell death. • The divergent metabolic phenotypes selected in 5% and 20% oxygen are semi-permanent.

  11. Acute stress responses: A review and synthesis of ASD, ASR, and CSR.

    PubMed

    Isserlin, Leanna; Zerach, Gadi; Solomon, Zahava

    2008-10-01

    Toward the development of a unifying diagnosis for acute stress responses this article attempts to find a place for combat stress reaction (CSR) within the spectrum of other defined acute stress responses. This article critically compares the diagnostic criteria of acute stress disorder (ASD), acute stress reaction (ASR), and CSR. Prospective studies concerning the predictive value of ASD, ASR, and CSR are reviewed. Questions, recommendations, and implications for clinical practice are raised concerning the completeness of the current acute stress response diagnoses, the heterogeneity of different stressors, the scope of expected outcomes, and the importance of decline in function as an indicator of future psychological, psychiatric, and somatic distress.

  12. Effect of acute and chronic cobalt administration on carotid body chemoreceptors responses.

    PubMed

    Morelli, L; Di Giulio, C; Iezzi, M; Data, P G

    1994-06-30

    Chronic cobalt exposure leads to release and production of erythropoietin and consequently to polycythemia. Accordingly, cellular elements sensitive to oxygen in the carotid body, would manifest responses during acute and chronic cobalt administration. The carotid body, detects gas changes (PO2, PCO2/pH) in the arterial blood and regulates ventilation and circulation by the afferent nerve discharge. We hypothesized that cobalt interacts with an oxygen sensitive mechanism in the carotid chemoreception and in erythropoietin producing cells. Twelve cats were anesthetized, paralysed and artificially ventilated; few fiber preparation of carotid sinus nerve were recorded during close intraarterial injection of cobalt. In another protocol, 12 rats received an intraperitoneal dose of CoCl2 (10 mg/kg) daily for 6 weeks. At the end, the carotid body was fixed in situ by superfusion. Ultrastructural and morphometric studies were made. Acute administration (0.08-2.3 mumol) promptly stimulated the chemoreceptor afferents. Type I cells increased significantly along with erythropoiesis in the chronic cobalt treated rats. The stimulatory effects of cobalt on the carotid body chemoreceptor showed that sensitive mechanisms in the kidney and in the carotid body are similar, and cobalt interacts with the physiological responses of oxygen.

  13. Time kinetics of the endocrine response to acute psychological stress.

    PubMed

    Richter, S D; Schürmeyer, T H; Schedlowski, M; Hädicke, A; Tewes, U; Schmidt, R E; Wagner, T O

    1996-05-01

    A first-time parachute jump was chosen as a model to evaluate the endocrine response to acute psychological stress. In 43 inexperienced tandem parachutists, blood was drawn continuously from 2 h before to 1 h after the jump and analyzed at 10-min intervals for plasma concentrations of epinephrine (E), norepinephrine (NE), cortisol, GH, PRL, and TSH. In addition, heart rate was recorded throughout the experiment. There was a significant increase in heart rate and E concentrations during the jump itself. NE, cortisol, GH, PRL, and TSH peaked with a latency of 10-20 min. Apart from cortisol and TSH concentrations, which were still elevated 1 h after the stress event, plasma levels of the other endocrine variables normalized within 1 h following the jump. Statistically significant cross-correlations could be observed between E and NE (r = 0.60, no time lag) and between E and PRL (r = 0.58, 10-min time lag) only. Even in a very homogenous group of subjects and under well-controlled conditions, endocrine responses to acute psychological stress show considerable variations.

  14. Sublethal effects of cadmium on physiological responses in the pocketbook mussel, Lampsilis ventricosa

    USGS Publications Warehouse

    Naimo, T.J.; Atchison, G.J.; Holland Bartels, L. E.

    1992-01-01

    Several physiological responses have been used to evaluate the effects of contaminants on marine bivalves. Respiration rate, food clearance rate, ammonia excretion rate, and food assimilation efficiency can be quantified and incorporated into a bioenergetics model known as scope for growth. This model estimates an organism's instantaneous energy budget and quantifies the available energy for growth and reproduction. We applied some of these physiological techniques to freshwater mussels to determine the sublethal effects of cadmium. The objective of our study was to quantify the physiological responses of adult pocketbook mussels, Lampsilis ventricosa , exposed to sublethal concentrations of cadmium. We selected L. ventricosa for study because it is abundant in the upper Mississippi River and its life history has been partially documented.

  15. Enhanced vagal baroreflex response during 24 h after acute exercise

    NASA Technical Reports Server (NTRS)

    Convertino, V. A.; Adams, W. C.

    1991-01-01

    We evaluated carotid-cardiac baroreflex responses in eight normotensive men (25-41 yr) on two different test days, each separated by at least 1 wk. On one day, baroreflex response was tested before and at 3, 6, 12, 18, and 24 h after graded supine cycle exercise to volitional exhaustion. On another day, this 24-h protocol was repeated with no exercise (control). Beat-to-beat R-R intervals were measured during external application of graded pressures to the carotid sinuses from 40 to -65 mmHg; changes of R-R intervals were plotted against carotid pressure (systolic pressure minus neck chamber pressure). The maximum slope of the response relationship increased (P less than 0.05) from preexercise to 12 h (3.7 +/- 0.4 to 7.1 +/- 0.7 ms/mmHg) and remained significantly elevated through 24 h. The range of the R-R response was also increased from 217 +/- 24 to 274 +/- 32 ms (P less than 0.05). No significant differences were observed during the control 24-h period. An acute bout of graded exercise designed to elicit exhaustion increases the sensitivity and range of the carotid-cardiac baroreflex response for 24 h and enhances its capacity to buffer against hypotension by increasing heart rate. These results may represent an underlying mechanism that contributes to blood pressure stability after intense exercise.

  16. Baroreflex Responses to Acute Changes in Blood Volume in Humans

    NASA Technical Reports Server (NTRS)

    Thompson, Cynthia A.; Tatro, Dana L.; Ludwig, David A.; Convertino, Victor A.

    1990-01-01

    To test the hypothesis that acute changes in plasma volume affect the stimulus-response relations of high- and low- pressure baroreflexes, eight men (27-44 yr old) underwent measurements for carotid-cardiac and cardiopulmonary baro-reflex responses under the following three volemic conditions: hypovolemic, normovolemic, and hypervolemic. The stimulus- response relation of the carotid-cardiac response curve was generated using a neck cuff device, which delivered pressure changes between +40 and -65 mmHg in continuous steps of 15 mmHg. The stimulus-response relationship, of the cardio-pulmonary baroreflex were studied by measurements of Forearm Vascular Resistance (FVR) and Peripheral Venous Pressure (PVP) during low levels of lower body negative pressure (O to -20 mmHg). The results indicate greater demand for vasoconstriction for equal reductions in venous pressure during progressive hypovolemia; this condition may compromise the capacity to provide adequate peripheral resistance during severe orthostatic stress. Fluid loading before reentry after spaceflight may act to restore vasoconstrictive capacity of the cardiopulmonary baroreflex but may not be an effective countermeasure against potential post- flight impairment of the carotid-cardiac baroreflex.

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

    PubMed Central

    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

  18. The Physiologic Response to Stress and its Effects on Swine Reproduction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    When exposed to a stressor, swine invoke behavioral and physiologic responses which are designed to enable the individual to cope with the negative effects of the stressor. The activity of the hypothalamic-pituitary-adrenal axis is increased resulting in elevated corticotropic releasing factor (CRF)...

  19. Physiological and metabolic responses of gestating Brahaman cows to repeated transportation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The purpose of this study was to examine physiological and metabolic responses to repeated transportation of gestating Brahman cows, previously classified as mature cows into temperament groups of Calm, Intermediate, or Temperamental. Brahman cows (n = 48) were subjected to 2 hours of transport (TRA...

  20. Physiological responses during the practice of synchronized swimming: a systematic review.

    PubMed

    Ponciano, Kátia; Miranda, Maria Luiza de Jesus; Homma, Miwako; Miranda, João Marcelo Queiroz; Figueira Júnior, Aylton J; Meira Júnior, Cássio De Miranda; Bocalini, Danilo Sales

    2017-02-06

    This study is aimed at analysing the scientific literature related to physiological responses in synchronized swimmers, produced from 2006 to 2016. A systematic review was conducted using electronic databases (Google Scholar, PubMed, SportDiscus, Web Science, Scielo and Scopus) in national and international journals. The articles were selected using the following inclusion criteria: composed samples of synchronized swimmers of both sexes, articles in English, Spanish and Portuguese, published from 2006 to 2016. Ten studies were included. The concentration of the articles and their publication was as follows: Europe (77%) and North America (23%). The protocols used analyse physiological responses in synchronized swimmers athletes during competitions or laboratory tests, lactate measurements, heart rate, rates of perceived exertion, VO2 and lung volume. The subjects of 100% of the studies included in this review were athletes of junior and senior categories who volunteered. Only 03 of the 10 studies have compared the physiological responses in volunteers who were not synchronized swimmers to synchronized swimmer athletes. The studies were conducted using different methodologies, which makes it difficult to compare them, so the standardization of instruments and definitions is essential for the scientific advancement in this field. In addition, it would be interesting to expand the research of these physiological responses in synchronized swimmers using base level or beginners as sample.

  1. Plant physiological response of strawberry fruit to chlorine dioxide gas treatment during postharvest storage

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Chlorine dioxide, a strong oxidizing and sanitizing agent, is used as a postharvest sanitizer for fruits and vegetables and generally applied on a packing line using a chlorine dioxide generator. The objective of this research was to study the physiological responses of strawberries to ClO2 when app...

  2. Testing the threat-sensitive predator avoidance hypothesis: physiological responses and predator pressure in wild rabbits.

    PubMed

    Monclús, Raquel; Palomares, Francisco; Tablado, Zulima; Martínez-Fontúrbel, Ana; Palme, Rupert

    2009-01-01

    Predation is a strong selective force with both direct and indirect effects on an animal's fitness. In order to increase the chances of survival, animals have developed different antipredator strategies. However, these strategies have associated costs, so animals should assess their actual risk of predation and shape their antipredator effort accordingly. Under a stressful situation, such as the presence of predators, animals display a physiological stress response that might be proportional to the risk perceived. We tested this hypothesis in wild European rabbits (Oryctolagus cuniculus), subjected to different predator pressures, in Doñana National Park (Spain). We measured the concentrations of fecal corticosterone metabolites (FCM) in 20 rabbit populations. By means of track censuses we obtained indexes of mammalian predator presence for each rabbit population. Other factors that could modify the physiological stress response, such as breeding status, food availability and rabbit density, were also considered. Model selection based on information theory showed that predator pressure was the main factor triggering the glucocorticoid release and that the physiological stress response was positively correlated with the indexes of the presence of mammalian carnivore predators. Other factors, such as food availability and density of rabbits, were considerably less important. We conclude that rabbits are able to assess their actual risk of predation and show a threat-sensitive physiological response.

  3. Renal Response to Volume Expansion: Learning the Experimental Approach in the Context of Integrative Physiology.

    ERIC Educational Resources Information Center

    Kline, Robert L.; Dukacz, Stephen A. W.; Stavraky, Thomas

    2000-01-01

    Describes a laboratory experience for upper-level science students that provides a hands-on approach to understanding the basics of experimental physiology. Students design an experiment to determine the relative importance of dilution of plasma proteins in the overall renal excretory response following volume expansion with intravenous saline.…

  4. Physiological responses of hard red winter wheat to infection by wheat streak mosaic virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wheat streak mosaic virus (WSMV) causes significant yield loss in hard red winter wheat in the U.S. Southern High Plains. Despite the prevalence of this pathogen, little is known about the physiological response of wheat to WSMV infection. A 2-year study was initiated to (i) investigate the effect o...

  5. Different Behavioral and Physiological Response in two Genetic Lines of Laying Hens Following Transportation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Physiological and behavioral response to transportation stress were examined in chickens selected for high group productivity and survivability (HGPS) resulting from reduced cannibalism and flightiness in colony cages and in chickens from Dekalb XL (DXL) commercial strain. At 13 wks of age, 96 pulle...

  6. Physiologic Responses of Able-Bodied and Paraplegic Males to Maximal Arm Ergometry.

    ERIC Educational Resources Information Center

    Israel, Richard G.; And Others

    A study compared physiologic responses of healthy paraplegic males to those of healthy, able-bodied males during maximal arm ergometry. Fifteen able-bodied, healthy adult males and 13 healthy adult male paraplegics followed an exercise program involving heart rate, increased exercise loads, and oxygen uptake. Results from an analysis of the data…

  7. Physiological Response and Childhood Anxiety: Association With Symptoms of Anxiety Disorders and Cognitive Bias

    ERIC Educational Resources Information Center

    Weems, Carl F.; Zakem, Alan H.; Costa, Natalie M.; Cannon, Melinda F.; Watts, Sarah E.

    2005-01-01

    This study examined the physiological response (skin conductance and heart rate [HR]) of youth exposed to a mildly phobic stimulus (video of a large dog) and its relation to child- and parent-reported anxiety symptoms and cognitive bias in a community-recruited sample of youth (n = 49). The results of this study indicated that HR and…

  8. Body Composition and Physiological Responses of Masters Female Swimmers 20 to 70 Years of Age.

    ERIC Educational Resources Information Center

    Vaccaro, Paul; And Others

    1984-01-01

    Female masters swimmers ranging in age from 20 to 69 were chosen for a study of their body composition and physiological responses at rest and during exercise. Two training groups were formed that differed on the basis of frequency, duration, and intensity of swimming workouts. Results are discussed. (Author/DF)

  9. The effects of autism and alexithymia on physiological and verbal responsiveness to music.

    PubMed

    Allen, Rory; Davis, Rob; Hill, Elisabeth

    2013-02-01

    It has been suggested that individuals with autism will be less responsive to the emotional content of music than typical individuals. With the aim of testing this hypothesis, a group of high-functioning adults on the autism spectrum was compared with a group of matched controls on two measures of emotional responsiveness to music, comprising physiological and verbal measures. Impairment in participants ability to verbalize their emotions (type-II alexithymia) was also assessed. The groups did not differ significantly on physiological responsiveness, but the autism group was significantly lower on the verbal measure. However, inclusion of the alexithymia score as a mediator variable nullified this group difference, suggesting that the difference was due not to absence of underlying emotional responsiveness to music in autism, but to a reduced ability to articulate it.

  10. Electric shock causes physiological stress responses in shore crabs, consistent with prediction of pain.

    PubMed

    Elwood, Robert W; Adams, Laura

    2015-11-01

    Animal pain is defined by a series of expectations or criteria, one of which is that there should be a physiological stress response associated with noxious stimuli. While crustacean stress responses have been demonstrated they are typically preceded by escape behaviour and thus the physiological change might be attributed to the behaviour rather than a pain experience. We found higher levels of stress as measured by lactate in shore crabs exposed to brief electric shock than non-shocked controls. However, shocked crabs showed more vigorous behaviour than controls. We then matched crabs with the same level of behaviour and still found that shocked crabs had stronger stress response compared with controls. The finding of the stress response, coupled with previous findings of long-term motivational change and avoidance learning, fulfils the criteria expected of a pain experience.

  11. Mortality, bioaccumulation and physiological responses in juvenile freshwater mussels (Lampsilis siliquoidea) chronically exposed to copper.

    PubMed

    Jorge, Marianna B; Loro, Vania L; Bianchini, Adalto; Wood, Chris M; Gillis, Patricia L

    2013-01-15

    Several studies have indicated that the early life stages of freshwater mussels are among the most sensitive aquatic organisms to inorganic chemicals, including copper. However, little is known about the toxic mode of action and sub-lethal effects of copper exposure in this group of imperiled animals. In this study, the physiological effects of long-term copper exposure (survival, growth, copper bioaccumulation, whole-body ion content, oxygen consumption, filtration rate, ATPase activities, and biomarkers of oxidative stress) were evaluated in juvenile (6 month old) mussels (Lampsilis siliquoidea). The mussels' recovery capacity and their ability to withstand further acute copper challenge were also evaluated in secondary experiments following the 28 day exposure by assessing survival, copper bioaccumulation and whole-body ion content. Mussels chronically exposed to 2 and 12 μg Cu/L showed significantly higher mortality than those held under control conditions (mortality 20.9, 69.9 and 12.5%, respectively), indicating that juvenile L. siliquoidea is underprotected by the U.S. Environmental Protection Agency (USEPA) biotic ligand model (BLM)-derived chronic water quality criteria (WQC) (2.18 μg Cu/L) and the hardness-derived USEPA WQC (12.16 μg Cu/L). Soft tissue copper burden increased equally for both copper exposures, suggesting that chronic toxicity is not associated with copper bioaccumulation. Several physiological disturbances were also observed during chronic copper exposure. Most relevant was a decrease in whole-body sodium content paralleled by an inhibition of Na(+) K(+)-ATPase activity, indicating a metal-induced ionoregulatory disturbance. Filtration and oxygen consumption rates were also affected. Redox parameters (reactive oxygen production, antioxidant capacity against peroxyl radicals, glutathione-S-transferase (GST) activity, and glutathione (GSH) concentration) did not show clear responses, but membrane damage as lipid peroxidation (LPO) was

  12. FDG-PET imaging for the assessment of physiologic volume response during radiotherapy in cervix cancer

    SciTech Connect

    Lin, Lilie L.; Yang Zhiyun; Mutic, Sasa; Miller, Tom R.; Grigsby, Perry W. . E-mail: pgrigsby@wustl.edu

    2006-05-01

    Purpose: To evaluate the physiologic tumor volume response during treatment in cervical cancer using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). Patients and Methods: This was a prospective study of 32 patients. Physiologic tumor volume in cubic centimeters was determined from the FDG-PET images using the 40% threshold method. Results: The mean pretreatment tumor volume was 102 cm{sup 3}. The mean volume by clinical Stages I, II, and III were 54, 79, and 176 cm{sup 3}, respectively. After 19.8 Gy external irradiation to the pelvis, the reduction in tumor volume was 29% (72 cm{sup 3}). An additional 13 Gy from high-dose-rate (HDR) brachytherapy reduced the mean volume to 15.4 cm{sup 3}, and this was subsequently reduced to 8.6 cm{sup 3} with 13 Gy additional HDR brachytherapy (26 Gy, HDR). Four patients had physiologic FDG uptake in the cervix at 3 months after the completion of therapy. The mean time to the 50% reduction in physiologic tumor volume was 19.9 days and after combined external irradiation and HDR to 24.9 Gy. Conclusion: These results indicate that physiologic tumor volume determination by FDG-PET is feasible and that a 50% physiologic tumor volume reduction occurs within 20 days of starting therapy.

  13. Sweat-inducing physiological challenges do not result in acute changes in hair cortisol concentrations.

    PubMed

    Grass, Juliane; Kirschbaum, Clemens; Miller, Robert; Gao, Wei; Steudte-Schmiedgen, Susann; Stalder, Tobias

    2015-03-01

    Hair cortisol concentrations (HCC) are assumed to provide a stable, integrative marker of long-term systemic cortisol secretion. However, contrary to this assumption, some recent observations have raised the possibility that HCC may be subject to acute influences, potentially related to cortisol incorporation from sweat. Here, we provide a first detailed in vivo investigation of this possibility comprising two independent experimental studies: study I (N=42) used a treadmill challenge to induce sweating together with systemic cortisol reactivity while in study II (N=52) a sauna bathing challenge induced sweating without systemic cortisol changes. In both studies, repeated assessments of HCC, salivary cortisol, cortisol in sweat and individuals' sweating rate (single assessment) were conducted on the experimental day and at a next-day follow-up. Results across the two studies consistently revealed that HCC were not altered by the acute interventions. Further, HCC were found to be unrelated to acute salivary cortisol reactivity, sweat cortisol levels, sweating rate or the time of examination. In line with previous data, cortisol levels in sweat were strongly related to total salivary cortisol output across the examined periods. The present results oppose recent case report data by showing that single sweat-inducing interventions do not result in acute changes in HCC. Our data also tentatively speak against the notion that cortisol in sweat may be a dominant source of HCC. Further, our findings also indicate that HCC are not subject to diurnal variation. This research provides further support for hair cortisol analysis as a marker of integrated long-term systemic cortisol secretion.

  14. Effect of an on-sight lead on the physiological and psychological responses to rock climbing.

    PubMed

    Draper, Nick; Jones, Glenys A; Fryer, Simon; Hodgson, Chris; Blackwell, Gavin

    2008-01-01

    Rock climbing is a multi-discipline activity that encompasses forms such as bouldering, top roping and lead climbing on natural and artificial climbing surfaces. A major focus of research has been explanation of physiological functioning. More recent research indicates that anxiety levels are elevated for less experienced climbers and in response to lead climbing ascents. Research regarding the demands of rock climbing has placed a lesser focus on the interaction of psychological and physiological factors. The objective of this study was to examine the effects of an on-sight lead climb on the physiological and psychological demands of the climb in comparison with a subsequent lead climb. Ten intermediate level climbers volunteered to complete the two climbing trials, on-sight lead climb (OSLC) and second lead climb (LC2). Climb time, lactate concentrations (baseline, pre climb, post climb and 15 min post climb), heart rate (1 min pre climb, peak HR, 1 min post climb and average climb across the duration of the climb), oxygen consumption, pre climb anxiety (CSAI-2R) were assessed for each climber for both trials. Results indicated that there were significant differences in self reported pre climb somatic and cognitive anxiety (t(9) = 2.79, p = 0.01, t(9) = 1.94, p = 0.043), climb time (t(9) = 3.07, p = 0.0052) and post climb lactate concentrations between the climbs (t(9) = 2.58, p = 0.015). These results indicate that psychological as well as physiological stress impact upon the response to rock climbing. The higher anxiety levels associated with an OSLC are likely to have influenced the physiological responses for the intermediate climbers in this study. Future studies should take into account the type of climbing, experience of climbers and the number of ascents as well as taking into account the interaction between physiological and psychological factors in response to rock climbing. Key pointsFor intermediate climbers, there are significant differences in

  15. Stunning fish with CO2 or electricity: contradictory results on behavioural and physiological stress responses.

    PubMed

    Gräns, A; Niklasson, L; Sandblom, E; Sundell, K; Algers, B; Berg, C; Lundh, T; Axelsson, M; Sundh, H; Kiessling, A

    2016-02-01

    Studies that address fish welfare before slaughter have concluded that many of the traditional systems used to stun fish including CO2 narcosis are unacceptable as they cause avoidable stress before death. One system recommended as a better alternative is electrical stunning, however, the welfare aspects of this method are not yet fully understood. To assess welfare in aquaculture both behavioural and physiological measurements have been used, but few studies have examined the relationship between these variables. In an on-site study aversive behaviours and several physiological stress indicators, including plasma levels of cortisol and ions as well as blood physiological variables, were compared in Arctic char (Salvelinus alpinus) stunned with CO2 or electricity. Exposure to water saturated with CO2 triggered aversive struggling and escape responses for several minutes before immobilization, whereas in fish exposed to an electric current immobilization was close to instant. On average, it took 5 min for the fish to recover from electrical stunning, whereas fish stunned with CO2 did not recover. Despite this, the electrically stunned fish had more than double the plasma levels of cortisol compared with fish stunned with CO2. This result is surprising considering that the behavioural reactions were much more pronounced following CO2 exposure. These contradictory results are discussed with regard to animal welfare and stress physiological responses. The present results emphasise the importance of using an integrative and interdisciplinary approach and to include both behavioural and physiological stress indicators in order to make accurate welfare assessments of fish in aquaculture.

  16. Physiological responses to error amplification in a robotic reaching adaptation task.

    PubMed

    Shirzad, Navid; Van der Loos, H F Machiel

    2014-01-01

    Analysis of physiological responses provides an objective measure of a person's affective state and has been proposed as a way to evaluate motivation and engagement of therapy clients during robot-assisted therapy regimens. This paper presents the analysis of three physiological responses to different levels of error amplification in a robotic reaching task to understand the feasibility of using physiological signals in order to modify therapy exercises to achieve higher participant attentiveness. In a pilot study with 22 healthy participants, we analyzed skin conductance, skin temperature, and respiration signals, with two main goals: 1) to compare physiological parameters between baseline (rest) and error-amplified reaching motion periods; and 2) to compare physiological parameters between reaching motion periods with different levels of error amplification. Results show that features extracted from skin conductance and respiration signals show significant differences between different error amplification levels. Features extracted from the skin temperature signal are not as reliable as measures of skin conductance and respiration, however they can provide supplementary information.

  17. Association of serum interleukin-6, interleukin-8, and Acute Physiology and Chronic Health Evaluation II score with clinical outcome in patients with acute respiratory distress syndrome

    PubMed Central

    Swaroopa, Deme; Bhaskar, Kakarla; Mahathi, T.; Katkam, Shivakrishna; Raju, Y. Satyanarayana; Chandra, Naval; Kutala, Vijay Kumar

    2016-01-01

    Background and Aim: Studies on potential biomarkers in experimental models of acute lung injury (ALI) and clinical samples from patients with ALI have provided evidence to the pathophysiology of the mechanisms of lung injury and predictor of clinical outcome. Because of the high mortality and substantial variability in outcomes in patients with acute respiratory distress syndrome (ARDS), identification of biomarkers such as cytokines is important to determine prognosis and guide clinical decision-making. Materials and Methods: In this study, we have included thirty patients admitted to Intensive Care Unit diagnosed with ARDS, and serum samples were collected on day 1 and 7 and were analyzed for serum interleukin-6 (IL-6) and IL-8 by ELISA method, and Acute Physiology and Chronic Health Evaluation II (APACHE II) scoring was done on day 1. Results: The mortality in the patients observed with ARDS was 34%. APACHE II score was significantly higher in nonsurvivors as compared to survivors. There were no significant differences in gender and biochemical and hematological parameters among the survivors and nonsurvivors. Serum IL-6 and IL-8 levels on day 1 were significantly higher in all the ARDS patients as compared to healthy controls and these levels were returned to near-normal basal levels on day 7. The serum IL-6 and IL-8 levels measured on day 7 were of survivors. As compared to survivors, the IL-6 and IL-8 levels were significantly higher in nonsurvivors measured on day 1. Spearman's rank correlation analysis indicated a significant positive correlation of APACHE II with IL-8. By using APACHE II score, IL-6, and IL-8, the receiver operating characteristic curve was plotted and the provided predictable accuracy of mortality (outcome) was 94%. Conclusion: The present study highlighted the importance of measuring the cytokines such as IL-6 and IL-8 in patients with ARDS in predicting the clinical outcome. PMID:27688627

  18. Determinants and short-term physiological consequences of PHA immune response in lesser kestrel nestlings.

    PubMed

    Rodríguez, Airam; Broggi, Juli; Alcaide, Miguel; Negro, Juan José; Figuerola, Jordi

    2014-08-01

    Individual immune responses are likely affected by genetic, physiological, and environmental determinants. We studied the determinants and short-term consequences of Phytohaemagglutinin (PHA) induced immune response, a commonly used immune challenge eliciting both innate and acquired immunity, on lesser kestrel (Falco naumanni) nestlings in semi-captivity conditions and with a homogeneous diet composition. We conducted a repeated measures analyses of a set of blood parameters (carotenoids, triglycerides, β-hydroxybutyrate, cholesterol, uric acid, urea, total proteins, and total antioxidant capacity), metabolic (resting metabolic rate), genotypic (MHC class II B heterozygosity), and biometric (body mass) variables. PHA challenge did not affect the studied physiological parameters on a short-term basis (<12 hr), except plasma concentrations of triglycerides and carotenoids, which decreased and increased, respectively. Uric acid was the only physiological parameter correlated with the PHA induced immune response (skin swelling), but the change of body mass, cholesterol, total antioxidant capacity, and triglycerides between sessions (i.e., post-pre treatment) were also positively correlated to PHA response. No relationships were detected between MHC gene heterozygosity or resting metabolic rate and PHA response. Our results indicate that PHA response in lesser kestrel nestlings growing in optimal conditions does not imply a severe energetic cost 12 hr after challenge, but is condition-dependent as a rapid mobilization of carotenoids and decrease of triglycerides is elicited on a short-term basis.

  19. Mechanosignaling in the vasculature: emerging concepts in sensing, transduction and physiological responses

    PubMed Central

    Fujiwara, Keigi; Pérez, Néstor Gustavo; Ushio-Fukai, Masuko; Fisher, Aron B.

    2015-01-01

    Cells are constantly exposed to mechanical forces that play a role in modulating cellular structure and function. The cardiovascular system experiences physical forces in the form of shear stress and stretch associated with blood flow and contraction, respectively. These forces are sensed by endothelial cells and cardiomyocytes and lead to responses that control vascular and cardiac homeostasis. This was highlighted at the Pan American Physiological Society meeting at Iguassu Falls, Brazil, in a symposium titled “Mechanosignaling in the Vasculature.” This symposium presented recent research that showed the existence of a vital link between mechanosensing and downstream redox sensitive signaling cascades. This link helps to transduce and transmit the physical force into an observable physiological response. The speakers showcased how mechanosensors such as ion channels, membrane receptor kinases, adhesion molecules, and other cellular components transduce the force via redox signals (such as reactive oxygen species and nitric oxide) to receptors (transcription factors, growth factors, etc.). Receptor activated pathways then lead to cellular responses including cellular proliferation, contraction, and remodeling. These responses have major relevance to the physiology and pathophysiology of various cardiovascular diseases. Thus an understanding of the complex series of events, from the initial sensing through the final response, is essential for progress in this field. Overall, this symposium addressed some important emerging concepts in the field of mechanosignaling and the eventual pathophysiological responses. PMID:25862828

  20. Natural variation in germination responses of Arabidopsis to seasonal cues and their associated physiological mechanisms

    PubMed Central

    Barua, Deepak; Butler, Colleen; Tisdale, Tracy E.; Donohue, Kathleen

    2012-01-01

    Background and Aims Despite the intense interest in phenological adaptation to environmental change, the fundamental character of natural variation in germination is almost entirely unknown. Specifically, it is not known whether different genotypes within a species are germination specialists to particular conditions, nor is it known what physiological mechanisms of germination regulation vary in natural populations and how they are associated with responses to particular environmental factors. Methods We used a set of recombinant inbred genotypes of Arabidopsis thaliana, in which linkage disequilibrium has been disrupted over seven generations, to test for genetic variation and covariation in germination responses to distinct environmental factors. We then examined physiological mechanisms associated with those responses, including seed-coat permeability and sensitivity to the phytohormones gibberellic acid (GA) and abscisic acid (ABA). Key Results Genetic variation for germination was environment-dependent, but no evidence for specialization of germination to different conditions was found. Hormonal sensitivities also exhibited significant genetic variation, but seed-coat properties did not. GA sensitivity was associated with germination responses to multiple environmental factors, but seed-coat permeability and ABA sensitivity were associated with specific germination responses, suggesting that an evolutionary change in GA sensitivity could affect germination in multiple environments, but that of ABA sensitivity may affect germination under more restricted conditions. Conclusions The physiological mechanisms of germination responses to specific environmental factors therefore can influence the ability to adapt to diverse seasonal environments encountered during colonization of new habitats or with future predicted climate change. PMID:22012958

  1. Ancestry trumps experience: Transgenerational but not early life stress affects the adult physiological stress response.

    PubMed

    McCormick, Gail L; Robbins, Travis R; Cavigelli, Sonia A; Langkilde, Tracy

    2017-01-01

    Exposure to stressors can affect an organism's physiology and behavior as well as that of its descendants (e.g. through maternal effects, epigenetics, and/or selection). We examined the relative influence of early life vs. transgenerational stress exposure on adult stress physiology in a species that has populations with and without ancestral exposure to an invasive predator. We raised offspring of eastern fence lizards (Sceloporus undulatus) from sites historically invaded (high stress) or uninvaded (low stress) by predatory fire ants (Solenopsis invicta) and determined how this different transgenerational exposure to stress interacted with the effects of early life stress exposure to influence the physiological stress response in adulthood. Offspring from these high- and low-stress populations were exposed weekly to either sub-lethal attack by fire ants (an ecologically relevant stressor), topical treatment with a physiologically-appropriate dose of the stress-relevant hormone, corticosterone (CORT), or a control treatment from 2 to 43weeks of age. Several months after treatments ended, we quantified plasma CORT concentrations at baseline and following restraint, exposure to fire ants, and adrenocorticotropic hormone (ACTH) injection. Exposure to fire ants or CORT during early life did not affect lizard stress physiology in adulthood. However, offspring of lizards from populations that had experienced multiple generations of fire ant-invasion exhibited more robust adult CORT responses to restraint and ACTH-injection compared to offspring from uninvaded populations. Together, these results indicate that transgenerational stress history may be at least as important, if not more important, than early life stress in affecting adult physiological stress responses.

  2. The dopaminergic response to acute stress in health and psychopathology: A systematic review.

    PubMed

    Vaessen, Thomas; Hernaus, Dennis; Myin-Germeys, Inez; van Amelsvoort, Thérèse

    2015-09-01

    Previous work in animals has shown that dopamine (DA) in cortex and striatum plays an essential role in stress processing. For the first time, we systematically reviewed the in vivo evidence for DAergic stress processing in health and psychopathology in humans. All studies included (n studies=25, n observations=324) utilized DA D2/3 positron emission tomography and measured DAergic activity during an acute stress challenge. The evidence in healthy volunteers (HV) suggests that physiological, but not psychological, stress consistently increases striatal DA release. Instead, increased medial prefrontal cortex (mPFC) DAergic activity in HV was observed during psychological stress. Across brain regions, stress-related DAergic activity was correlated with the physiological and psychological intensity of the stressor. The magnitude of stress-induced DA release was dependent on rearing conditions, personality traits and genetic variations in several SNPs. In psychopathology, preliminary evidence was found for stress-related dorsal striatal DAergic hyperactivity in psychosis spectrum and a blunted response in chronic cannabis use and pain-related disorders, but results were inconsistent. Physiological stress-induced DAergic activity in striatum in HV may reflect somatosensory properties of the stressor and readiness for active fight-or-flight behavior. DAergic activity in HV in the ventral striatum and mPFC may be more related to expectations about the stressor and threat evaluation, respectively. Future studies with increased sample size in HV and psychopathology assessing the functional relevance of stress-induced DAergic activity, the association between cortical and subcortical DAergic activity and the direct comparison of different stressors are necessary to conclusively elucidate the role of the DA system in the stress response.

  3. Metabolomics of Ramadan fasting: an opportunity for the controlled study of physiological responses to food intake

    PubMed Central

    2014-01-01

    High-throughput screening techniques that analyze the metabolic endpoints of biological processes can identify the contributions of genetic predisposition and environmental factors to the development of common diseases. Studies applying controlled physiological challenges can reveal dysregulation in metabolic responses that may be predictive for or associated with these diseases. However, large-scale epidemiological studies with well controlled physiological challenge conditions, such as extended fasting periods and defined food intake, pose logistic challenges. Culturally and religiously motivated behavioral patterns of life style changes provide a natural setting that can be used to enroll a large number of study volunteers. Here we report a proof of principle study conducted within a Muslim community, showing that a metabolomics study during the Holy Month of Ramadan can provide a unique opportunity to explore the pre-prandial and postprandial response of human metabolism to nutritional challenges. Up to five blood samples were obtained from eleven healthy male volunteers, taken directly before and two hours after consumption of a controlled meal in the evening on days 7 and 26 of Ramadan, and after an over-night fast several weeks after Ramadan. The observed increases in glucose, insulin and lactate levels at the postprandial time point confirm the expected physiological response to food intake. Targeted metabolomics further revealed significant and physiologically plausible responses to food intake by an increase in bile acid and amino acid levels and a decrease in long-chain acyl-carnitine and polyamine levels. A decrease in the concentrations of a number of phospholipids between samples taken on days 7 and 26 of Ramadan shows that the long-term response to extended fasting may differ from the response to short-term fasting. The present study design is scalable to larger populations and may be extended to the study of the metabolic response in defined patient

  4. Metabolomics of Ramadan fasting: an opportunity for the controlled study of physiological responses to food intake.

    PubMed

    Mathew, Sweety; Krug, Susanne; Skurk, Thomas; Halama, Anna; Stank, Antonia; Artati, Anna; Prehn, Cornelia; Malek, Joel A; Kastenmüller, Gabi; Römisch-Margl, Werner; Adamski, Jerzy; Hauner, Hans; Suhre, Karsten

    2014-06-06

    High-throughput screening techniques that analyze the metabolic endpoints of biological processes can identify the contributions of genetic predisposition and environmental factors to the development of common diseases. Studies applying controlled physiological challenges can reveal dysregulation in metabolic responses that may be predictive for or associated with these diseases. However, large-scale epidemiological studies with well controlled physiological challenge conditions, such as extended fasting periods and defined food intake, pose logistic challenges. Culturally and religiously motivated behavioral patterns of life style changes provide a natural setting that can be used to enroll a large number of study volunteers. Here we report a proof of principle study conducted within a Muslim community, showing that a metabolomics study during the Holy Month of Ramadan can provide a unique opportunity to explore the pre-prandial and postprandial response of human metabolism to nutritional challenges. Up to five blood samples were obtained from eleven healthy male volunteers, taken directly before and two hours after consumption of a controlled meal in the evening on days 7 and 26 of Ramadan, and after an over-night fast several weeks after Ramadan. The observed increases in glucose, insulin and lactate levels at the postprandial time point confirm the expected physiological response to food intake. Targeted metabolomics further revealed significant and physiologically plausible responses to food intake by an increase in bile acid and amino acid levels and a decrease in long-chain acyl-carnitine and polyamine levels. A decrease in the concentrations of a number of phospholipids between samples taken on days 7 and 26 of Ramadan shows that the long-term response to extended fasting may differ from the response to short-term fasting. The present study design is scalable to larger populations and may be extended to the study of the metabolic response in defined patient

  5. Acute phase response in cattle infected with Anaplasma marginale.

    PubMed

    Nazifi, S; Razavi, S M; Kaviani, F; Rakhshandehroo, E

    2012-03-23

    This study was undertaken to evaluate the acute phase responses via the assessment of the concentration of serum sialic acids (total, lipid bound and protein bound), inflammatory mediators (IFN-γ and TNF-α) and acute phase proteins (Hp and SAA) in 20 adult crossbred cattle naturally infected by Anaplasma marginale. The infected animals were divided into 2 subgroups on the basis of parasitemia rate (<20% and >20%). Also, as a control group, 10 clinically healthy cattle from the same farms were sampled. Our data revealed significant decreases in red blood cell count (RBC), hematocrite (PCV) and hemoglobine (Hb) in infected cattle compared to healthy ones. Conversely, the concentrations of Hp, SAA, ceruloplasmin, fibrinogen, serum sialic acids and the circulatory IFN-γ and TNF-α were increased in the diseased cattle (P<0.05). In addition, it was evident that the progression of parasitemia in infected cattle did not induce any significant alterations in the hematological indices (RBCs, PCV and Hb) and the concentrations of Hp, SAA, ceruloplasmin and fibrinogen. SAA was the most sensitive factor to change in the diseased cattle. Therefore, increase in SAA concentration may be a good indicator of inflammatory process in cattle naturally infected with Anaplasma marginale.

  6. Transforming Water: Social Influence Moderates Psychological, Physiological, and Functional Response to a Placebo Product

    PubMed Central

    Crum, Alia J.; Phillips, Damon J.; Goyer, J. Parker; Akinola, Modupe; Higgins, E. Tory

    2016-01-01

    This paper investigates how social influence can alter physiological, psychological, and functional responses to a placebo product and how such responses influence the ultimate endorsement of the product. Participants consumed a product, “AquaCharge Energy Water,” falsely-labeled as containing 200 mg of caffeine but which was actually plain spring water, in one of three conditions: a no social influence condition, a disconfirming social influence condition, and a confirming social influence condition. Results demonstrated that the effect of the product labeling on physiological alertness (systolic blood pressure), psychological alertness (self-reported alertness), functional alertness (cognitive interference), and product endorsement was moderated by social influence: participants experienced more subjective, physiological and functional alertness and stronger product endorsement when they consumed the product in the confirming social influence condition than when they consumed the product in the disconfirming social influence condition. These results suggest that social influence can alter subjective, physiological, and functional responses to a faux product, in this case transforming the effects of plain water. PMID:27875567

  7. Comparison of physiological responses to graded exercise test performance in outrigger canoeing.

    PubMed

    Kerr, Rebecca M; Spinks, Warwick; Leicht, Anthony S; Sinclair, Wade; Woodside, Louise

    2008-05-01

    The aim of this study was to establish a graded exercise test protocol for determining the peak physiological responses of female outrigger canoeists. Seventeen trained female outrigger canoeists completed two outrigger ergometer graded exercise test protocols in random order: (1) 25 W power output for 2 min increasing by 7.5 W every minute until exhaustion; and (2) 25 W power output for 2 min increasing by 15 W every 2 min to exhaustion. Heart rate and power output were recorded every 15 s. Expired air was collected continuously and sampled for analysis at 15-s intervals, while blood lactate concentration was measured immediately after and 3, 5, and 7 min after exercise. The peak physiological and performance variables examined included peak oxygen uptake (VO2peak), minute ventilation, tidal volume, ventilatory thresholds 1 and 2, respiratory rate, respiratory exchange ratio, heart rate, blood lactate concentration, power output, performance time, and time to VO2peak. There were no significant differences in peak physiological responses, ventilatory thresholds or performance variables between the two graded exercise test protocols. Despite no significant differences between protocols, due to the large limits of agreement evident between protocols for the peak physiological responses, it is recommended that the same protocol be used for all comparison testing to minimize intra-individual variability of results.

  8. Physiological responses to increased brood size and ectoparasite infestation: Adult great tits favour self-maintenance.

    PubMed

    Wegmann, Michele; Voegeli, Beatrice; Richner, Heinz

    2015-03-15

    Different types of stressors trigger responses of different physiological systems, and these responses may contribute differentially to the maintenance of homeostasis, to trade-offs and the evolution of life-history traits. To manipulate two common stressors during reproduction, we infested half of the nests in a naturally breeding great tit population with ectoparasites and simultaneously manipulated brood size, using a 2×2 experimental design. Parents in this model species commonly compensate for ectoparasites by an increase in food provisioning. We assessed parental responses to these concurrent stressors by measuring several physiological stress parameters such as changes in metabolic rate, oxidative stress and expression of heat-shock proteins (Hsp), and explored how these stressors affect the trade-off between self-maintenance and reproduction. Neither flea infestation nor brood size manipulation affected adult metabolic rate, oxidative damage or Hsp levels. Furthermore, we found no interactive effect of the two treatments on adults. However, nestlings in infested nests had lower body mass and lower survival. Nestlings in enlarged broods were lighter and had lower survival, although parents of enlarged broods increased food provisioning rate. The findings suggest that adults favour maintenance of cellular homeostasis, and physiological equilibrium over current reproduction, and that the costs induced by both stressors, flea infestation and increased brood size, are carried by the offspring. It emphasizes the importance of self-maintenance over reproduction in life-history decisions, and more generally the need of including physiological traits for understanding the evolution of life-histories.

  9. Physiological responses of the European cockle Cerastoderma edule (Bivalvia: Cardidae) as indicators of coastal lagoon pollution.

    PubMed

    Nilin, Jeamylle; Pestana, João Luís Teixeira; Ferreira, Nuno Gonçalo; Loureiro, Susana; Costa-Lotufo, Letícia Veras; Soares, Amadeu M V M

    2012-10-01

    Physiological responses can be used as effective parameters to identify environmentally stressful conditions. In this study, physiology changes such as oxygen consumption, clearance rate, survival in air, condition index and energy reserves were measured on natural populations of cockles collected from different sites at Ria de Aveiro, Portugal. At those sites, sediment samples were collected for Hg concentration analysis. Cockles were used for the evaluation of both the Hg concentration and physiological response. Mercury was detected in the cockle tissue and in the sediment collected from the sampling points both nearby and distant from the main mercury contamination source. The energy content was negatively correlated with both Hg concentration in cockle tissues and survival in air. Nonetheless, the energy content was positively correlated with the condition index, and there was a positive correlation between the survival in air test and the tissue mercury concentration. A PCA-factor analysis explained 86.8% of the total variance. The principal factor (62.7%) consisted of the air survival, the Hg in soft tissues (positive) and the condition index (negative). The second factor (24.1%) consisted of a negative correlation between the oxygen consumption and the clearance rate. Due to their sensitivity to environmental conditions, the physiological responses of cockles can be used to assess the ecological status of aquatic environments. More effort should be invested in investigating the effects of environmental perturbations on cockle health once they are a good reporter organism.

  10. Interaction of infection with Renibacterium salmoninarum and physical stress in juvenile chinook salmon: Physiological responses, disease progression, and mortality

    USGS Publications Warehouse

    Mesa, M.G.; Maule, A.G.; Schreck, C.B.

    2000-01-01

    We experimentally infected juvenile spring chinook salmon Oncorhynchus tshawytscha with Renibacterium salmoninarum (Rs), the causative agent of bacterial kidney disease (BKD), in order to compare the physiological responses of Rs-infected and Rs-noninfected fish to a series of multiple, acute stressors and to determine whether exposure to these stressors worsens the infection and leads to increased mortality. After subjecting groups of fish to a waterborne challenge of Rs, we sampled them biweekly to monitor infection levels, mortality, and some stress-related physiological changes. As infections worsened, fish developed decreased hematocrits and blood glucose levels and increased levels of cortisol and lactate, indicating that BKD is stressful, particularly during the later stages. Eight weeks after the challenge, when fish had moderate to high infection levels, we subjected them, along with unchallenged control fish, to three 60-s bouts of hypoxia, struggling, and mild agitation that were separated by 48-72 h. Our results indicate that the imposition of these stressors on Rs-infected fish did not lead to higher infection levels or increased mortality when compared with diseased fish that did not receive the stressors. Furthermore, the kinetics of plasma cortisol, glucose, and lactate over a 24-h period following each application of the stressor were similar between fish with moderate to high Rs infections and those that had low or no detectable infection. Some differences in the stress responses of these two groups did exist, however. Most notably, fish with moderate to high Rs infections had higher titers of cortisol and lactate prior to each application of the stressor and also were unable to consistently elicit a significant hyperglycemia in response to the stressors. Collectively, our results should be important in understanding the impact that BKD has on the survival of juvenile salmonids, but we caution that our results represent the combined effects of one

  11. Peritraumatic dissociation and physiological response to trauma-relevant stimuli in Vietnam combat veterans with posttraumatic stress disorder.

    PubMed

    Kaufman, Milissa L; Kimble, Matthew O; Kaloupek, Danny G; McTeague, Lisa M; Bachrach, Peter; Forti, Allison M; Keane, Terence M

    2002-03-01

    A recent study found that female rape victims with acute posttraumatic stress disorder (PTSD) who received a high score on the Peritraumatic Dissociative Experiences Questionnaire exhibited suppression of physiological responses during exposure to trauma-related stimuli. The goal of our present study was to test whether the same relationship holds true for male Vietnam combat veterans with chronic PTSD, using secondary analyses applied to data derived from a Veteran's Affairs Cooperative Study. Vietnam combat veterans (N = 1238) completed measures to establish combat-related PTSD diagnostic status, extent of PTSD-related symptomatic distress, and presence of dissociative symptoms during their most stressful combat-related experiences. Extreme subgroups of veterans with current PTSD were classified as either low dissociators (N = 118) or high dissociators (N = 256) based on an abbreviated version of the Peritraumatic Dissociative Experiences Questionnaire. Dependent variables reflected subjective distress along with heart rate, skin conductance, electromyographic, and blood pressure data when responding to neutral and trauma-related audiovisual and imagery presentations. Veterans in the current PTSD group had significantly higher dissociation scores than did veterans in the lifetime and never PTSD groups. Among veterans with current PTSD, high dissociators reported greater PTSD-related symptomatic distress than did low dissociators, but the groups did not differ with respect to physiological reactivity to the trauma-related laboratory presentations. Our results replicate the previously reported relationship between peritraumatic dissociation and PTSD status in Vietnam combat veterans. However, we found no association between peritraumatic dissociation and the extent of physiological responding to trauma-relevant cues in male veterans with chronic combat-related PTSD.

  12. Mobilized adult pituitary stem cells contribute to endocrine regeneration in response to physiological demand.

    PubMed

    Rizzoti, Karine; Akiyama, Haruhiko; Lovell-Badge, Robin

    2013-10-03

    Pituitary hormone deficiencies, with Growth Hormone deficiency being most frequent (1 in 3,500-10,000 births), cause significant morbidity. Regeneration of missing endocrine cells would be a significant improvement over hormone replacement therapies, which incur side effects and do not mimic physiological secretion patterns. Recent in vitro studies have identified a population of adult pituitary progenitors that express the HMG box transcription factors SOX2 and SOX9. Here, we apply cell-lineage tracing analysis to demonstrate that SOX2- and SOX9-expressing progenitors can self-renew and give rise to endocrine cells in vivo, suggesting that they are tissue stem cells. Moreover, we show that they can become mobilized and differentiate into the appropriate endocrine cell types in response to physiological stress. Our results highlight the pituitary as a model for exploring how physiological changes influence stem cell behavior and suggest that manipulation of endogenous pituitary stem cells is a potential therapeutic strategy for pituitary deficiencies.

  13. Detecting variable responses in time-series using repeated measures ANOVA: Application to physiologic challenges

    PubMed Central

    Macey, Paul M.; Schluter, Philip J.; Macey, Katherine E.; Harper, Ronald M.

    2016-01-01

    We present an approach to analyzing physiologic timetrends recorded during a stimulus by comparing means at each time point using repeated measures analysis of variance (RMANOVA). The approach allows temporal patterns to be examined without an a priori model of expected timing or pattern of response. The approach was originally applied to signals recorded from functional magnetic resonance imaging (fMRI) volumes-of-interest (VOI) during a physiologic challenge, but we have used the same technique to analyze continuous recordings of other physiological signals such as heart rate, breathing rate, and pulse oximetry. For fMRI, the method serves as a complement to whole-brain voxel-based analyses, and is useful for detecting complex responses within pre-determined brain regions, or as a post-hoc analysis of regions of interest identified by whole-brain assessments. We illustrate an implementation of the technique in the statistical software packages R and SAS. VOI timetrends are extracted from conventionally preprocessed fMRI images. A timetrend of average signal intensity across the VOI during the scanning period is calculated for each subject. The values are scaled relative to baseline periods, and time points are binned. In SAS, the procedure PROC MIXED implements the RMANOVA in a single step. In R, we present one option for implementing RMANOVA with the mixed model function “lme”. Model diagnostics, and predicted means and differences are best performed with additional libraries and commands in R; we present one example. The ensuing results allow determination of significant overall effects, and time-point specific within- and between-group responses relative to baseline. We illustrate the technique using fMRI data from two groups of subjects who underwent a respiratory challenge. RMANOVA allows insight into the timing of responses and response differences between groups, and so is suited to physiologic testing paradigms eliciting complex response patterns

  14. A Puzzle of Vestibular Physiology in a Meniere's Disease Acute Attack

    PubMed Central

    Martinez-Lopez, Marta; Manrique-Huarte, Raquel; Perez-Fernandez, Nicolas

    2015-01-01

    The aim of this paper is to present for the first time the functional evaluation of each of the vestibular receptors in the six semicircular canals in a patient diagnosed with Meniere's disease during an acute attack. A 54-year-old lady was diagnosed with left Meniere's disease who during her regular clinic review suffers an acute attack of vertigo, with fullness and an increase of tinnitus in her left ear. Spontaneous nystagmus and the results in the video head-impulse test (vHIT) are shown before, during, and after the attack. Nystagmus was initially left beating and a few minutes later an upbeat component was added. No skew deviation was observed. A decrease in the gain of the vestibuloocular reflex (VOR) and the presence of overt saccades were observed when the stimuli were in the plane of the left superior semicircular canal. At the end of the crisis nystagmus decreased and vestibuloocular reflex returned to almost normal. A review of the different possibilities to explain these findings points to a hypothetical utricular damage. PMID:26167320

  15. Innate immune inflammatory response in the acutely ischemic myocardium.

    PubMed

    Deftereos, Spyridon; Angelidis, Christos; Bouras, Georgios; Raisakis, Konstantinos; Gerckens, Ulrich; Cleman, Michael W; Giannopoulos, Georgios

    2014-01-01

    The "holy grail" of modern interventional cardiology is the salvage of viable myocardial tissue in the distribution of an acutely occluded coronary artery. Thrombolysis and percutaneous coronary interventions, provided they can be delivered on time, can interrupt the occlusion and save tissue. At the same time restoring the patency of the coronary vessels and providing the ischemic myocardium with blood can cause additional tissue damage. A key element of ischemic and reperfusion injury and major determinant of the evolution of damage in the injured myocardium is the inflammatory response. The innate immune system initiates and directs this response which is a prerequisite for subsequent healing. The complement cascade is set in motion following the release of subcellular membrane constituents. Endogenous 'danger' signals known as danger-associated molecular patterns (DAMPs) released from ischemic and dying cells alert the innate immune system and activate several signal transduction pathways through interactions with the highly conserved Toll like receptors (TLRs). Reactive oxygen species (ROS) generation directly induces pro-inflammatory cascades and triggers formation of the inflammasome. The challenge lies into designing strategies that specifically block the inflammatory cascades responsible for tissue damage without affecting those concerned with tissue healing.

  16. Physiological and behavioral responses in Drosophila melanogaster to odorants present at different plant maturation stages.

    PubMed

    Versace, Elisabetta; Eriksson, Anna; Rocchi, Federico; Castellan, Irene; Sgadò, Paola; Haase, Albrecht

    2016-09-01

    The fruit fly Drosophila melanogaster feeds and oviposits on fermented fruit, hence its physiological and behavioral responses are expected to be tuned to odorants abundant during later stages of fruit maturation. We used a population of about two-hundred isogenic lines of D. melanogaster to assay physiological responses (electroantennograms (EAG)) and behavioral correlates (preferences and choice ratio) to odorants found at different stages of fruit maturation. We quantified electrophysiological and behavioral responses of D. melanogaster for the leaf compound β-cyclocitral, as well as responses to odorants mainly associated with later fruit maturation stages. Electrophysiological and behavioral responses were modulated by the odorant dose. For the leaf compound we observed a steep dose-response curve in both EAG and behavioral data and shallower curves for odorants associated with later stages of maturation. Our data show the connection between sensory and behavioral responses and are consistent with the specialization of D. melanogaster on fermented fruit and avoidance of high doses of compounds associated with earlier stages of maturation. Odor preferences were modulated in a non-additive way when flies were presented with two alternative odorants, and combinations of odorants elicited higher responses than single compounds.

  17. What Constitutes Effective Coping and Efficient Physiologic Regulation following Psychosocial Stress Depends on Involuntary Stress Responses

    PubMed Central

    Bendezú, Jason J.; Perzow, Sarah E. D.; Wadsworth, Martha E.

    2017-01-01

    This study utilized a random-assignment experimental design to examine the interactive contributions of youth-reported trait involuntary stress responses (ISRs) and effortful coping on physiologic reactivity and recovery patterns in preadolescent boys and girls. Fourth- and fifth-grade child-parent dyads (N=126) participated in this study. Children were exposed to the Trier Social Stress Test (TSST-C) and then to one of two randomly-assigned experimental coping conditions: behavioral distraction and cognitive avoidance. Children’s ISRs were examined as predictors of salivary cortisol and alpha-amylase (sAA) reactivity as well as moderators of the effect of coping condition on cortisol and sAA recovery trajectories. Multi-level modeling analyses did not link ISRs to physiologic reactivity patterning. ISRs and coping condition interacted to predict differential physiologic recovery trajectories. In the distraction condition, children reporting high ISR levels displayed less efficient cortisol and sAA recovery than children reporting low ISR levels. Surprisingly, the opposite was found for children reporting high ISR levels in the avoidance condition. These children displayed more efficient physiologic recovery relative to their high ISR level peers in the distraction condition. Findings suggest that the efficiency of preadolescents’ physiologic recovery following stress may depend on regulatory fit between children’s ISR levels and cues from their coping environment. PMID:27448527

  18. Physiological responses of the seagrass Posidonia oceanica as indicators of fish farm impact.

    PubMed

    Pérez, Marta; García, Tania; Invers, Olga; Ruiz, Juan Manuel

    2008-05-01

    The development of aquaculture along the Mediterranean coastline degrades the marine environment, in particular Posidonia oceanica meadows, which, in extreme cases, show high mortality. Here we studied the effects of organic matter and nutrient input from the effluents of three fish farms, located along the Mediterranean coast, on P. oceanica physiology. For this purpose, we measured physiological variables such as total nitrogen (N) content, free amino acid (FAA) concentration and composition, N stable isotope ratio (delta 15N), total phosphorus (P) content and total non-structural carbohydrate (TNC) content in plant tissues and epiphytes affected by organic discharges (highly impacted stations: HI, and less impacted stations: LI) and compared these results with those obtained in references sites (control stations: C). For all the descriptors analyzed in P. oceanica epiphytes, the values recorded in the vicinity of cages were, in general, much higher than those in C. Leaves did not respond consistently in any case. Total N content and delta 15N in epiphytes together with the total P content in rhizomes and epiphytes were the physiological descriptors that showed the most consistent responses to fish farm effluents. On the basis of these observations, we conclude that fish farm activities strongly affect the physiological parameters of nearby P. oceanica meadows. We propose that changes in these physiological parameters may be useful indicators of marine environmental degradation in studies that monitor the effects of fish farming.

  19. Early Biventricular Molecular Responses to an Acute Myocardial Infarction

    PubMed Central

    Erdal, Cenk; Karakülah, Gökhan; Fermancı, Emel; Kunter, İmge; Silistreli, Erdem; Canda, Tülay; Erdal, Esra; Hepaguslar, Hasan

    2012-01-01

    Background: Acute myocardial infarction (AMI) remains as one of the most common lethal diseases in the world and therefore it is necessary to understand its effect on molecular basis. Genome-wide microarray analysis provides us to predict potential biomarkers and signaling pathways for this purpose. Objectives: The aim of this study is to understand the molecular basis of the immediate right ventricular cellular response to left ventricular AMI. Material and Methods: A rat model of left anterior descending coronary artery ligation was used to assess the effect of left ventricular AMI on both the right ventricle as a remote zone and the left ventricle as an ischemic/infarct zone. Microarray technology was applied to detect the gene expression. Gene Ontology and KEGG pathways analysis were done to identify effected pathways and related genes. Results: We found that immune response, cell chemotaxis, inflammation, cytoskeleton organization are significantly deregulated in ischemic zone as early response within 30 min. Unexpectedly, there were several affected signaling pathways such as cell chemotaxis, regulation of endothelial cell proliferation, and regulation of caveolea regulation of anti-apoptosis, regulation of cytoskeleton organization and cell adhesion on the remote zone in the right ventricle. Conclusion: This data demonstrates that there is an immediate molecular response in both ventricles after an AMI. Although the ischemia did not histologically involve the right ventricle; there is a clear molecular response to the infarct in the left ventricle. This provides us new insights to understand molecular mechanisms behind AMI and to find more effective drug targets. PMID:22211093

  20. Delayed system response times affect immediate physiology and the dynamics of subsequent button press behavior.

    PubMed

    Kohrs, Christin; Hrabal, David; Angenstein, Nicole; Brechmann, André

    2014-11-01

    System response time research is an important issue in human-computer interactions. Experience with technical devices and general rules of human-human interactions determine the user's expectation, and any delay in system response time may lead to immediate physiological, emotional, and behavioral consequences. We investigated such effects on a trial-by-trial basis during a human-computer interaction by measuring changes in skin conductance (SC), heart rate (HR), and the dynamics of button press responses. We found an increase in SC and a deceleration of HR for all three delayed system response times (0.5, 1, 2 s). Moreover, the data on button press dynamics was highly informative since subjects repeated a button press with more force in response to delayed system response times. Furthermore, the button press dynamics could distinguish between correct and incorrect decisions and may thus even be used to infer the uncertainty of a user's decision.

  1. Biomechanical and Physiological Response to a Contemporary Soccer Match-Play Simulation.

    PubMed

    Page, Richard M; Marrin, Kelly; Brogden, Chris M; Greig, Matt

    2015-10-01

    The intermittent activity profile of soccer match play increases the complexity of the physical demands. Laboratory models of soccer match play have value in controlled intervention studies, developed around manipulations of the activity profile to elicit a desired physiological or biomechanical response. Contemporary notational analyses suggest a profile comprising clusters of repeat sprint efforts, with implications for both biomechanical and physiological load. Eighteen male soccer players completed a 90-minute treadmill protocol based on clusters of repeat sprint efforts. Each 15-minute bout of exercise was quantified for uniaxial (medial-lateral [PLML], anterior-posterior [PLAP], and vertical [PLV]) and triaxial PlayerLoad (PLTotal). The relative contributions of the uniaxial PlayerLoad vectors (PLML%, PLAP%, and PLV%) were also examined. In addition to rating of perceived exertion, the physiological response comprised heart rate, blood lactate concentration, and both peak and average oxygen consumption. Triaxial PlayerLoad increased (p = 0.02) with exercise duration (T0-15 = 206.26 ± 14.37 a.u. and T45-60 = 214.51 ± 14.97 a.u.) and remained elevated throughout the second half. This fatigue effect was evident in both the PLML and PLAP movement planes. The mean relative contributions of PLV%:PLAP%:PLML% were consistent at ∼48:28:23. The physiological response was comparable with match play, and a similar magnitude of increase at ∼5% was observed in physiological parameters. Changes in PlayerLoad might reflect a change in movement quality with fatigue, with implications for both performance and injury risk, reflecting observations of match play. The high frequency of speed change elicits a 23% contribution from mediolateral load, negating the criticism of treadmill protocols as "linear."

  2. Physiological responses of freeze-tolerant and -intolerant frogs: clues to evolution of anuran freeze tolerance.

    PubMed

    Costanzo, J P; Lee, R E; Lortz, P H

    1993-10-01

    Freeze tolerance in the wood frog, Rana sylvatica, is promoted by multiple, integrated physiological responses to ice forming within body tissues. By analyzing the freezing responses of the sympatric, but freeze intolerant, leopard frog (R. pipiens), we sought clues to the evolution of anuran freeze tolerance. Physiological responses critical to R. sylvatica's freeze tolerance, such as the synthesis and distribution of the cryoprotectant glucose, protective dehydration of organs, and deferred cardiac failure, were present, but comparatively less pronounced, in R. pipiens. Both species were innately tolerant of hyperglycemia. Glucose supplements did not enhance the freezing viability of R. pipiens, although in vitro tests of cryoprotectant efficacy revealed that glucose and glycerol provided comparable protection to erythrocytes of both species. We conclude that the evolution of freeze tolerance in R. sylvatica is not only promoted by its desiccation tolerance and the fortuitous biophysical consequences of freezing (e.g., exothermic induction of cardioacceleration and moderation of cooling rate) but also involves a progressive enhancement of fundamental physiological stress responses.

  3. Activation of physiological stress responses by a natural reward: Novel vs. repeated sucrose intake.

    PubMed

    Egan, Ann E; Ulrich-Lai, Yvonne M

    2015-10-15

    Pharmacological rewards, such as drugs of abuse, evoke physiological stress responses, including increased heart rate and blood pressure, and activation of the hypothalamic-pituitary-adrenal (HPA) axis. It is not clear to what extent the natural reward of palatable foods elicits similar physiological responses. In order to address this question, HPA axis hormones, heart rate, blood pressure and brain pCREB immunolabeling were assessed following novel and repeated sucrose exposure. Briefly, adult, male rats with ad libitum food and water were given either a single (day 1) or repeated (twice-daily for 14 days) brief (up to 30 min) exposure to a second drink bottle containing 4 ml of 30% sucrose drink vs. water (as a control for bottle presentation). Sucrose-fed rats drank more than water-fed on all days of exposure, as expected. On day 1 of exposure, heart rate, blood pressure, plasma corticosterone, and locomotion were markedly increased by presentation of the second drink bottle regardless of drink type. After repeated exposure (day 14), these responses habituated to similar extents regardless of drink type and pCREB immunolabeling in the hypothalamic paraventricular nucleus (PVN) also did not vary with drink type, whereas basolateral amygdala pCREB was increased by sucrose intake. Taken together, these data suggest that while sucrose is highly palatable, physiological stress responses were evoked principally by the drink presentation itself (e.g., an unfamiliar intervention by the investigators), as opposed to the palatability of the offered drink.

  4. Physiological responses during matches and profile of elite pencak silat exponents.

    PubMed

    Aziz, Abdul Rashid; Tan, Benedict; Teh, Kong Chuan

    2002-12-01

    This is a descriptive, cross-sectional study describing the physiological responses during competitive matches and profile of elite exponents of an emerging martial art sport, pencak silat. Thirty exponents (21 males and 9 females) were involved in the study. Match responses (i.e. heart rate (HR) throughout match and capillary blood lactate concentration, [La], at pre-match and at the end of every round) were obtained during actual competitive duels. Elite silat exponents' physiological attributes were assessed via anthropometry, vertical jump, isometric grip strength, maximal oxygen uptake, and the Wingate 30 s anaerobic test of the upper and lower body, in the laboratory. The match response data showed that silat competitors' mean HR was > 84% of estimated HR maximum and levels of [La] ranged from 6.7 - 18.7 mMol(-1) during matches. This suggests that competitive silat matches are characterised by high aerobic and anaerobic responses. In comparison to elite taekwondo and judo athletes' physiological characteristics, elite silat exponents have lower aerobic fitness and grip strength, but greater explosive leg power (vertical jump). Generally, they also possessed a similar anaerobic capability in the lower but markedly inferior anaerobic capability in the upper body.

  5. Effect of coffee ingestion on physiological responses and ratings of perceived exertion during submaximal endurance exercise.

    PubMed

    Demura, Shinichi; Yamada, Takayoshi; Terasawa, Naoko

    2007-12-01

    This study examined the effect of coffee ingestion on physiological responses and ratings of perceived exertion (RPE) during submaximal endurance exercises by 10 healthy young adults. Participants performed a submaximal endurance cycling exercise corresponding to 60% of maximum oxygen uptake capacity for 60 min. They drank either caffeinated coffee with a caffeine content of 6 mg/kg body-mass of each participant (Caf) or a decaffeinated coffee (Dec) 60 min. before starting exercise. Participants participated in the blind design experiment under both conditions at a one-week interval. Oxygen uptake, respiratory exchange ratio, heart rate, RPE, and plasma lactate concentration were measured during the endurance exercise. The RPE under the Caffeinated coffee condition during the last 60 min. of endurance exercise was significantly lower than that in the Decaffeinated coffee condition. However, no significant differences in any physiological response were observed between conditions. Thus, caffeine ingestion 60 min. before starting exercise had an insignificant effect on the physiological responses, except for RPE during submaximal endurance exercises for 60 min. Caffeine ingestion before endurance exercise of relatively low intensity may have a beneficial effect on psychological responses.

  6. Physiological Responses During Matches and Profile of Elite Pencak Silat Exponents

    PubMed Central

    Aziz, Abdul Rashid; Tan, Benedict; Teh, Kong Chuan

    2002-01-01

    This is a descriptive, cross-sectional study describing the physiological responses during competitive matches and profile of elite exponents of an emerging martial art sport, pencak silat. Thirty exponents (21 males and 9 females) were involved in the study. Match responses (i.e. heart rate (HR) throughout match and capillary blood lactate concentration, [La], at pre-match and at the end of every round) were obtained during actual competitive duels. Elite silat exponents’ physiological attributes were assessed via anthropometry, vertical jump, isometric grip strength, maximal oxygen uptake, and the Wingate 30 s anaerobic test of the upper and lower body, in the laboratory. The match response data showed that silat competitors’ mean HR was > 84% of estimated HR maximum and levels of [La] ranged from 6.7 - 18.7 mMol-1 during matches. This suggests that competitive silat matches are characterised by high aerobic and anaerobic responses. In comparison to elite taekwondo and judo athletes’ physiological characteristics, elite silat exponents have lower aerobic fitness and grip strength, but greater explosive leg power (vertical jump). Generally, they also possessed a similar anaerobic capability in the lower but markedly inferior anaerobic capability in the upper body. PMID:24748847

  7. Affective and physiological sexual response patterns: the effects of instructions on sexually functional and dysfunctional men.

    PubMed

    Heiman, J R; Rowland, D L

    1983-01-01

    To more clearly characterize the patterns of cognitive-affective and physiological responses concomitant with male sexual dysfunction, the present study compared 14 sexually dysfunctional and 16 sexually functional men. All individuals listened to two sexually explicit tapes and engaged in a self-generated fantasy, while genital, heart rate and scaled cognitive affective responses were recorded. Two types of instructions, a performance demand set and a non-demand sensate focus set, preceded the erotic tapes in counterbalanced order. As predicted, dysfunctional men showed less genital tumescence to tapes preceded by the demand than the non-demand instructions. Contrary to expectation, functional men showed greater penile tumescence to the tapes preceded by demand instructions. Self-reported sexual arousal did not follow the penile tumescence pattern but instead indicated that the dysfunctional sample was significantly less subjectively aroused to the tapes and fantasy. There were other significant differences between the groups. Dysfunctional men showed greater general psychological distress, as measured by the SCL-90, including elevated somaticism, anxiety and depression scores. During the experimental session, dysfunctional men also evidenced greater awareness of a variety of physiological responses, as well as more negative and fewer positive cognitive-affective states. These data are discussed in terms of the interaction of affective and physiological responses, differences in contextual meanings of instructional sets given the presence of a dysfunction, and theoretical and clinical conceptualizations of male sexual functioning.

  8. Physiological and gene expression responses of sunflower (Helianthus annuus L.) plants differ according to irrigation placement.

    PubMed

    Aguado, Ana; Capote, Nieves; Romero, Fernando; Dodd, Ian C; Colmenero-Flores, José M

    2014-10-01

    To investigate effects of soil moisture heterogeneity on plant physiology and gene expression in roots and leaves, three treatments were implemented in sunflower plants growing with roots split between two compartments: a control (C) treatment supplying 100% of plant evapotranspiration, and two treatments receiving 50% of plant evapotranspiration, either evenly distributed to both compartments (deficit irrigation - DI) or unevenly distributed to ensure distinct wet and dry compartments (partial rootzone drying - PRD). Plants receiving the same amount of water responded differently under the two irrigation systems. After 3 days, evapotranspiration was similar in C and DI, but 20% less in PRD, concomitant with decreased leaf water potential (Ψleaf) and increased leaf xylem ABA concentration. Six water-stress responsive genes were highly induced in roots growing in the drying soil compartment of PRD plants, and their expression was best correlated with local soil water content. On the other hand, foliar gene expression differed significantly from that of the root and correlated better with xylem ABA concentration and Ψleaf. While the PRD irrigation strategy triggered stronger physiological and molecular responses, suggesting a more intense and systemic stress reaction due to local dehydration of the dry compartment of PRD plants, the DI strategy resulted in similar water savings without strongly inducing these responses. Correlating physiological and molecular responses in PRD/DI plants may provide insights into the severity and location of water deficits and may enable a better understanding of long-distance signalling mechanisms.

  9. Vulnerability to predation and physiological stress responses of experimentally descaled juvenile Chinook salmon, Oncorhynchus tshawytscha

    USGS Publications Warehouse

    Gadomski, Dena M.; Mesa, Matthew G.; Olson, Todd M.

    1994-01-01

    Juvenile salmonids,Oncorhynchus spp., commonly encounter conditions (e.g., during hatchery release and dam passage) that result in damage to the skin, scale, and slime complex. We conducted laboratory experiments to determine if descaling of juvenile chinook salmon,O. tshawytscha, increased their vulnerability to predation, and to assess the physiological stress responses elicited by descaling. Salmon were experimentally descaled on either 10% or 20% of their total body area. When offered equal numbers of control and descaled juvenile chinook salmon, northern squawfish,Ptychocheilus oregonensis, did not consume significantly more of either prey type (48–60% of consumed prey were descaled). Juvenile chinook salmon descaled on 10% of their body area did show significant physiological stress responses, however. Mean concentrations of plasma cortisol peaked 1 h after descaling, and returned to control levels by 12 h. Plasma glucose peaked 3 h post-treatment and remained elevated for 24 h. Plasma lactate increased immediately following treatment and returned to undisturbed control levels by 3 h. The osmoregulatory response of plasma potassium was highly variable, but plasma sodium decreased immediately and remained low for 24 h. The observed physiological responses suggest that descaling of juvenile chinook salmon could result in decreased resistance to disease and other stressors encountered in the field, possibly leading to reduced performance capacity and lowered survival.

  10. Physiological and cognitive responses when riding an electrically assisted bicycle versus a classical bicycle.

    PubMed

    Theurel, J; Theurel, A; Lepers, R

    2012-01-01

    The present study compared the physiological responses and the subsequent cognitive performance when riding an electrically assisted (EB) versus a classical (CB) bicycle. Oxygen uptake, heart rate and leg extensor muscles electromyographic (EMG) activity were recorded in 10 subjects during a 30-min intermittent cycling exercise performed with EB versus CB. Cognitive performance was evaluated by a mail sorting test, performed at rest and after each cycling session. Averaged oxygen uptake and heat rate were significantly (P < 0.05) lower during EB cycling than during CB cycling. The EMG activities of the vastus lateralis, rectus femoris and gastrocnemius medialis muscles were significantly (P < 0.001) greater during CB cycling than during EB cycling. The time to complete the mail sorting test was significantly (P < 0.05) shorter after EB cycling than after CB cycling. Because EB cycling reduced muscle strains and physiological stress, it might offer benefits for those using bicycles in their work, such as postal workers and police officers. STATEMENT OF RELEVANCE: This study compared physiological and cognitive responses when riding an electrically assisted versus a classical bicycle. The results showed that the electrically assisted bicycle led to reduced muscle strains and physiological stress and, therefore, might offer benefits for those using bicycles in their work, such as postal workers and police officers.

  11. Comparative physiological and proteomic responses to drought stress in two poplar species originating from different altitudes.

    PubMed

    Yang, Fan; Wang, Yong; Miao, Ling-Feng

    2010-08-01

    Cuttings of Populus kangdingensis C. Wang et Tung and Populus cathayana Rehder were examined during a single growing season in a greenhouse for comparative analysis of their physiological and proteomic responses to drought stress. The said species originate from high and low altitudes, respectively, of the eastern Himalaya. Results revealed that the adaptive responses to drought stress vary between the two poplar species. As a consequence of drought stress, the stem height increment and leaf number increment are more significantly inhibited in P. cathayana compared with P. kangdingensis. On the other hand, in response to drought stress, more significant cellular damages such as reduction in leaf relative water content and CO(2) assimilation rate, increments in the contents of malondialdehyde and hydrogen peroxide and downregulation or degradation of proteins related to photosynthesis occur in P. cathayana compared with P. kangdingensis. On the other hand, P. kangdingensis can cope better with the negative impact on the entire regulatory network. This includes more efficient increases in content of solute sugar, soluble protein and free proline and activities of antioxidant enzymes, as well as specific expressions of certain proteins related to protein processing, redox homeostasis and sugar metabolism. Morphological consequences as well as physiological and proteomic responses to drought stress between species revealed that P. kangdingensis originating from a high altitude manifest stronger drought adaptation than did P. cathayana originating from a low altitude. Functions of various proteins identified by proteomic experiment are related with physiological phenomena. Physiological and proteomic responses to drought stress in poplar may work cooperatively to establish a new cellular homeostasis, allowing poplar to develop a certain level of drought tolerance.

  12. Response of Two Mytilids to a Heatwave: The Complex Interplay of Physiology, Behaviour and Ecological Interactions

    PubMed Central

    Gestoso, Ignacio; Lima, Fernando P.; Vázquez, Elsa; Comeau, Luc A.; Gomes, Filipa; Seabra, Rui

    2016-01-01

    Different combinations of behavioural and physiological responses may play a crucial role in the ecological success of species, notably in the context of biological invasions. The invasive mussel Xenostrobus securis has successfully colonised the inner part of the Galician Rias Baixas (NW Spain), where it co-occurs with the commercially-important mussel Mytilus galloprovincialis. This study investigated the effect of a heatwave on the physiological and behavioural responses in monospecific or mixed aggregations of these species. In a mesocosm experiment, mussels were exposed to simulated tidal cycles and similar temperature conditions to those experienced in the field during a heat-wave that occurred in the summer of 2013, when field robo-mussels registered temperatures up to 44.5°C at low tide. The overall responses to stress differed markedly between the two species. In monospecific aggregations M. galloprovincialis was more vulnerable than X. securis to heat exposure during emersion. However, in mixed aggregations, the presence of the invader was associated with lower mortality in M. galloprovincialis. The greater sensitivity of M. galloprovincialis to heat exposure was reflected in a higher mortality level, greater induction of Hsp70 protein and higher rates of respiration and gaping activity, which were accompanied by a lower heart rate (bradycardia). The findings show that the invader enhanced the physiological performance of M. galloprovincialis, highlighting the importance of species interactions in regulating responses to environmental stress. Understanding the complex interactions between ecological factors and physiological and behavioural responses of closely-related species is essential for predicting the impacts of invasions in the context of future climate change. PMID:27736896

  13. Response of Two Mytilids to a Heatwave: The Complex Interplay of Physiology, Behaviour and Ecological Interactions.

    PubMed

    Olabarria, Celia; Gestoso, Ignacio; Lima, Fernando P; Vázquez, Elsa; Comeau, Luc A; Gomes, Filipa; Seabra, Rui; Babarro, José M F

    2016-01-01

    Different combinations of behavioural and physiological responses may play a crucial role in the ecological success of species, notably in the context of biological invasions. The invasive mussel Xenostrobus securis has successfully colonised the inner part of the Galician Rias Baixas (NW Spain), where it co-occurs with the commercially-important mussel Mytilus galloprovincialis. This study investigated the effect of a heatwave on the physiological and behavioural responses in monospecific or mixed aggregations of these species. In a mesocosm experiment, mussels were exposed to simulated tidal cycles and similar temperature conditions to those experienced in the field during a heat-wave that occurred in the summer of 2013, when field robo-mussels registered temperatures up to 44.5°C at low tide. The overall responses to stress differed markedly between the two species. In monospecific aggregations M. galloprovincialis was more vulnerable than X. securis to heat exposure during emersion. However, in mixed aggregations, the presence of the invader was associated with lower mortality in M. galloprovincialis. The greater sensitivity of M. galloprovincialis to heat exposure was reflected in a higher mortality level, greater induction of Hsp70 protein and higher rates of respiration and gaping activity, which were accompanied by a lower heart rate (bradycardia). The findings show that the invader enhanced the physiological performance of M. galloprovincialis, highlighting the importance of species interactions in regulating responses to environmental stress. Understanding the complex interactions between ecological factors and physiological and behavioural responses of closely-related species is essential for predicting the impacts of invasions in the context of future climate change.

  14. Comparison of thrombolysis in myocardial infarction, Global Registry of Acute Coronary Events, and Acute Physiology and Chronic Health Evaluation II risk scores in patients with acute myocardial infarction who require mechanical ventilation for more than 24 hours.

    PubMed

    Eran, Oren; Novack, Victor; Gilutz, Harel; Zahger, Doron

    2011-02-01

    The ability to provide an accurate prognosis in an intensive care unit is of major importance. Numerous risk scores have been developed to predict hospital mortality based on demographic, physiologic, and clinical data. These scores were universally developed in general medical or surgical intensive care units. Patients admitted to a cardiac care unit differ in many aspects from those admitted to general medical intensive care units. Few patients require mechanical ventilation and prolonged intensive care. Performance of risk scores developed for patients with acute myocardial infarction (AMI) in this subgroup is unknown. We prospectively studied 51 consecutive patients who were admitted to a cardiac care unit from September 2006 to March 2008 for AMI and received mechanical ventilation for >24 hours. Acute Physiology and Chronic Health Evaluation II (APACHE II), Thrombolysis In Myocardial Infarction, and Global Registry of Acute Coronary Events risk scores were calculated for each patient. Mortality rates were extrapolated based on these 3 risk scores. Twenty-two of 51 patients (43%) died in hospital. Age, mean arterial pressure, urea, albumin, hemoglobin, need for vasopressors, and estimated glomerular filtration rate were predictive of mortality. APACHE II and Global Registry of Acute Coronary Events scores were higher in nonsurvivors but Thrombolysis In Myocardial Infarction risk score was not predictive of mortality. APACHE II score had the highest value for area under receiver operator characteristics curve for mortality prediction. In conclusion, patients with AMI requiring mechanical ventilation have a high mortality rate. This risk is predicted by co-morbidities better than by direct cardiac parameters. Consequently, conventional AMI risk scores do not perform well in this very sick population and the APACHE II score better predicts their short-term outcome.

  15. Prior exposure to capture heightens the corticosterone and behavioural responses of little penguins (Eudyptula minor) to acute stress

    PubMed Central

    Carroll, Gemma; Turner, Emma; Dann, Peter; Harcourt, Rob

    2016-01-01

    Studies of physiology can provide important insight into how animals are coping with challenges in their environment and can signal the potential effects of exposure to human activity in both the short and long term. In this study, we measured the physiological and behavioural response of little penguins (Eudyptula minor) that were naïve to human activity over 30 min of capture and handling. We assessed relationships between corticosterone secretion, behaviour, sex and time of day in order to characterize the determinants of the natural stress response. We then compared the response of these naïve penguins with the responses of female little penguins that had been exposed to research activity (bimonthly nest check and weighing) and to both research activity (monthly nest check and weighing) and evening viewing by tourists. We found that corticosterone concentrations increased significantly over 30 min of capture, with naïve penguins demonstrating a more acute stress response during the day than at night. Penguins that had previously been exposed to handling at the research and research/visitor sites showed elevated corticosterone concentrations and consistently more aggressive behaviour after 30 min compared with naïve birds, although there were no significant differences in baseline corticosterone concentrations. Our findings demonstrate that these little penguins have not habituated to routine capture, but rather mount a heightened physiological and behavioural response to handling by humans. Less invasive research monitoring techniques, such as individual identification with PIT tags and automatic recording and weighing, and a reduction in handling during the day should be considered to mitigate some of the potentially negative effects of disturbance. Given the paucity of data on the long-term consequences of heightened stress on animal physiology, our study highlights the need for further investigation of the relationship between the corticosterone

  16. Behavioral Avoidance - Will Physiological Insecticide Resistance Level of Insect Strains Affect Their Oviposition and Movement Responses?

    PubMed

    Nansen, Christian; Baissac, Olivier; Nansen, Maria; Powis, Kevin; Baker, Greg

    2016-01-01

    Agricultural organisms, such as insect herbivores, provide unique opportunities for studies of adaptive evolutionary processes, including effects of insecticides on movement and oviposition behavior. In this study, Brassica leaves were treated with one of two non-systemic insecticides and exposed to two individual strains (referred to as single or double resistance) of diamondback moth (Plutella xylostella) (DBM) exhibiting physiological resistance. Behavioral responses by these two strains were compared as part of characterizing the relative effect of levels of physiological resistance on the likelihood of insects showing signs of behavioral avoidance. For each DBM strain, we used choice bioassays to quantify two possible types of behavioral avoidance: 1) females ovipositing predominantly on leaf surfaces without insecticides, and 2) larvae avoiding insecticide-treated leaf surfaces. In three-choice bioassays (leaves with no pesticide, 50% coverage with pesticide, or 100% coverage with pesticide), females from the single resistance DBM strain laid significantly more eggs on water treated leaves compared to leaves with 100% insecticide coverage (both gamma-cyhalothrin and spinetoram). Females from the double resistance DBM strain also laid significantly more eggs on water treated leaves compared to leaves with 100% gamma-cyhalothrin, while moths did not adjust their oviposition behavior in response to spinetoram. Larvae from the single resistance DBM strain showed a significant increase in mobility in response to both insecticides and avoided insecticide-treated portions of leaves when given a choice. On the other hand, DBM larvae from the double resistance strain showed a significant decrease in mobility in response to insecticides, and they did not avoid insecticide-treated portions of leaves when given a choice. Our results suggest that pest populations with physiological resistance may show behavioral avoidance, as resistant females avoided oviposition on

  17. Behavioral Avoidance - Will Physiological Insecticide Resistance Level of Insect Strains Affect Their Oviposition and Movement Responses?

    PubMed Central

    Nansen, Christian; Baissac, Olivier; Nansen, Maria; Powis, Kevin; Baker, Greg

    2016-01-01

    Agricultural organisms, such as insect herbivores, provide unique opportunities for studies of adaptive evolutionary processes, including effects of insecticides on movement and oviposition behavior. In this study, Brassica leaves were treated with one of two non-systemic insecticides and exposed to two individual strains (referred to as single or double resistance) of diamondback moth (Plutella xylostella) (DBM) exhibiting physiological resistance. Behavioral responses by these two strains were compared as part of characterizing the relative effect of levels of physiological resistance on the likelihood of insects showing signs of behavioral avoidance. For each DBM strain, we used choice bioassays to quantify two possible types of behavioral avoidance: 1) females ovipositing predominantly on leaf surfaces without insecticides, and 2) larvae avoiding insecticide-treated leaf surfaces. In three-choice bioassays (leaves with no pesticide, 50% coverage with pesticide, or 100% coverage with pesticide), females from the single resistance DBM strain laid significantly more eggs on water treated leaves compared to leaves with 100% insecticide coverage (both gamma-cyhalothrin and spinetoram). Females from the double resistance DBM strain also laid significantly more eggs on water treated leaves compared to leaves with 100% gamma-cyhalothrin, while moths did not adjust their oviposition behavior in response to spinetoram. Larvae from the single resistance DBM strain showed a significant increase in mobility in response to both insecticides and avoided insecticide-treated portions of leaves when given a choice. On the other hand, DBM larvae from the double resistance strain showed a significant decrease in mobility in response to insecticides, and they did not avoid insecticide-treated portions of leaves when given a choice. Our results suggest that pest populations with physiological resistance may show behavioral avoidance, as resistant females avoided oviposition on

  18. Acute hormonal responses following different velocities of eccentric exercise.

    PubMed

    Libardi, Cleiton A; Nogueira, Felipe R D; Vechin, Felipe C; Conceição, Miguel S; Bonganha, Valéria; Chacon-Mikahil, Mara Patricia T

    2013-11-01

    The aim of this study was to compare the acute hormonal responses following two different eccentric exercise velocities. Seventeen healthy, untrained, young women were randomly placed into two groups to perform five sets of six maximal isokinetic eccentric actions at slow (30° s(-1) ) and fast (210° s(-1) ) velocities with 60-s rest between sets. Growth hormone, cortisol, free and total testosterone were assessed by blood samples collected at baseline, immediately postexercise, 5, 15 and 30 min following eccentric exercise. Changes in hormonal responses over time were compared between groups, using a mixed model followed by a Tukey's post hoc test. The main findings of the present study were that the slow group showed higher growth hormone values immediately (5·08 ± 2·85 ng ml(-1) , P = 0·011), 5 (5·54 ± 3·01 ng ml(-1) , P = 0·004) and 15 min (4·30 ± 2·87 ng ml(-1) , P = 0·021) posteccentric exercise compared with the fast group (1·39 ± 2·41 ng ml(-1) , 1·34 ± 1·97 ng ml(-1) and 1·24 ± 1·87 ng ml(-1) , respectively), and other hormonal responses were not different between groups (P>0·05). In conclusion, slow eccentric exercise velocity enhances more the growth hormone(GH) response than fast eccentric exercise velocity without cortisol and testosterone increases.

  19. Moderation of physiological stress responses by personality traits and daily hassles: less flexibility of immune system responses.

    PubMed

    Peters, Madelon L; Godaert, Guido L R; Ballieux, Rudy E; Heijnen, Coby J

    2003-12-01

    Previously we demonstrated that stressors varying on the dimension of mental effort and controllability have distinctive effects on cardiovascular, endocrine and immune system responses. The purpose of the present study was to relate individual differences in physiological stress responsivity to task appraisal and stress-induced mood changes (issue 1), trait characteristics (issue 2) and daily hassles (issue 3). Appraisal and mood changes did not mediate the differential effects of the stressors. The trait characteristics, aggression and external locus of control and daily hassles moderated the effect of the stressor on physiological parameters, especially immune parameters. Moreover, the moderation effect was different in the high versus the low effort stress task. High aggression, high external locus of control and more daily hassles were associated with increased reactivity in the low effort condition and decreased reactivity in the high effort condition, which is suggested to reflect less differentiated responding to changing task demands and hence, less flexibility in the immune system.

  20. Acute phase response in lame crossbred dairy cattle

    PubMed Central

    Bagga, A.; Randhawa, Swaran Singh; Sharma, S.; Bansal, B. K.

    2016-01-01

    Aim: The study was undertaken to study acute phase response based on acute phase proteins (APPs) such as C-reactive protein (CRP), haptoglobin (Hp), serum amyloid A (SAA), and fibrinogen in lame crossbred dairy cattle. Materials and Methods: Lame animals (n=30) were selected within 3-7 days of being noticed as lame by the farm veterinarian, from a local dairy farm in southeast Ludhiana over a period of 6 months, stratified proportionately with respect to stage of lactation with non-lame healthy cows (n=10). All the cows were otherwise healthy and did not have any other inflammatory problems such as pneumonia, enteritis, mastitis, or any kind of acute uterine inflammation. Blood samples were collected from all the animals; serum and plasma samples were separated and stored at −20°C. The levels of CRP, Hp, and SAA were estimated using Sandwich ELISA, whereas fibrinogen was estimated by heat precipitation method. Results: SAA levels in lame cows were significantly higher (22.19±0.85 µg/ml), approximately 3 times as compared to non-lame cows (8.89±0.72 µg/ml), whereas serum Hp concentration was approximately 20 times higher in the lame cattle (21.71±3.32 mg/dl) as compared to non-lame cows (1.17±0.07 mg/dl). Fibrinogen also increased in the lame cattle (3.97±0.22 g/L) as compared to non-lame group (1.40±0.17 g/L). Serum CRP levels analyzed in the lame cattle for the first time in the present study, and significant high concentration was appreciated in lame cattle (4.41±0.33 mg/L) as compared to non-lame cattle (0.61±0.14 mg/L). Lame cattle were having more of sole hemorrhages, sole ulcers, and white line lesions as compared to non-lame cattle. Conclusion: It can be concluded that lame cattle exhibit high levels of APPs including CRP, Hp, SAA, and fibrinogen as compared to non-lame cattle. PMID:27956769

  1. The acute hormonal response to the kettlebell swing exercise.

    PubMed

    Budnar, Ronald G; Duplanty, Anthony A; Hill, David W; McFarlin, Brian K; Vingren, Jakob L

    2014-10-01

    The purpose of this investigation was to examine the acute hormonal response to the kettlebell swing exercise. Ten recreationally resistance trained men (age, 24 ± 4 years; height, 175 ± 6 cm; body mass, 78.7 ± 9.9 kg) performed 12 rounds of 30 seconds of 16 kg kettlebell swings alternated with 30 seconds of rest. Blood samples were collected before (PRE), immediately after (IP), and 15 (P15) and 30 minutes after exercise (P30) and analyzed for testosterone (T), immunoreactive growth hormone, cortisol (C), and lactate concentrations. Heart rate and rating of perceived exertion were measured at the end of each round. Testosterone was significantly higher (p ≤ 0.05) at IP than at PRE, P15, or P30 (PRE: 28 ± 3; IP: 32 ± 4; P15: 29 ± 3; P30: 27 ± 3 nmol·L). Growth hormone was higher at IP, P15, and P30 than at PRE (PRE: 0.1 ± 0.1; IP: 1.8 ± 1.2; P15: 2.1 ± 1.1; P30: 1.6 ± 1.3 μg·L). Cortisol was higher at IP and P15 than at PRE and P30 (PRE: 617 ± 266; IP: 894 ± 354; P15: 875 ± 243; P30: 645 ± 285 nmol·L). Lactate was higher at IP, P15, and P30 than at PRE (PRE: 1.1 ± 0.5; IP: 7.0 ± 3.0; P15: 4.0 ± 2.7; P30: 2.5 ± 1.8 mmol·L). Heart rate increased progressively from 57 ± 12 at PRE to 170 ± 10 at IP. The exercise protocol produced an acute increase in hormones involved in muscle adaptations. Thus, the kettlebell swing exercise might provide a good supplement to resistance training programs.

  2. Physiologic responses to water immersion in man: A compendium of research

    NASA Technical Reports Server (NTRS)

    Kollias, J.; Vanderveer, D.; Dorchak, K. J.; Greenleaf, J. E.

    1976-01-01

    A total of 221 reports published through December 1973 in the area of physiologic responses to water immersion in man were summarized. The author's abstract or summary was used whenever possible. Otherwise, a detailed annotation was provided under the subheadings: (1) purpose, (2) procedures and methods, (3) results, and (4) conclusions. The annotations are in alphabetical order by first author; author and subject indexes are included. Additional references are provided in the selected bibliography.

  3. The effect of melody on the physiological responses of heel sticks pain in neonates

    PubMed Central

    Marofi, Maryam; Nikobakht, Farzaneh; Badiee, Zohreh; Golchin, Mehri

    2015-01-01

    Background: During health care in the neonatal intensive care unit (NICU), infants undergo extremely painful procedures, which may cause problems, if not controlled, such as changes in the pattern of respiratory rate, heart rate, and blood oxygen saturation. The present study aimed to find the effect of melody on the physiological responses of neonates’ heel stick pain. Materials and Methods: This quasi-experimental study was conducted in Alzahra Hospital (Isfahan, Iran) for 5 months. Fifty infants were selected through convenient sampling method and were randomly assigned in equal numbers to two groups (n = 25). In the melody group (intervention), a selected melody was played for the infants at a distance of 1 m from them, with a sound intensity of 65 dB, from 3 minutes before, during, and after the heel stick procedure, respectively, and their physiological responses were observed with a monitoring system and recorded at the afore-mentioned time periods. Physiological responses were also recorded in the control group (no intervention) 3 min before, during, and after the heel stick procedure, respectively. Results: Means of respiratory and pulse rates in the melody and control groups showed a significant difference at different time points. But the mean blood oxygen saturation in the melody group showed no significant difference at different time points, although the difference was significant in the control group. Conclusions: The results showed that melody could maintain more balance in some physiological responses of infants, such as the respiratory rate and pulse rate during the Guthrie test. Therefore, melody is recommended to be used to prevent the destructive effects of pain in infants during painful procedures. PMID:26120343

  4. Physiological and growth responses to water deficit in the bioenergy crop Miscanthus x giganteus.

    PubMed

    Ings, Jennifer; Mur, Luis A J; Robson, Paul R H; Bosch, Maurice

    2013-01-01

    High yielding perennial biomass crops of the species Miscanthus are widely recognized as one of the most promising lignocellulosic feedstocks for the production of bioenergy and bioproducts. Miscanthus is a C4 grass and thus has relatively high water use efficiency. Cultivated Miscanthus comprises primarily of a single clone, Miscanthus x giganteus, a sterile hybrid between M. sacchariflorus and M. sinensis. M. x giganteus is high yielding and expresses desirable combinations of many traits present in the two parental species types; however, it responds poorly to low water availability. To identify the physiological basis of the response to water stress in M. x giganteus and to identify potential targets for breeding improvements we characterized the physiological responses to water-deficit stress in a pot experiment. The experiment has provided valuable insights into the temporal aspects of drought-induced responses of M. x giganteus. Withholding water resulted in marked changes in plant physiology with growth-associated traits among the first affected, the most rapid response being a decline in the rate of stem elongation. A reduction in photosynthetic performance was among the second set of changes observed; indicated by a decrease in stomatal conductance followed by decreases in chlorophyll fluorescence and chlorophyll content. Measures reflecting the plant water status were among the last affected by the drought treatment. Metabolite analysis indicated that proline was a drought stress marker in M. x giganteus, metabolites in the proline synthesis pathway were more abundant when stomatal conductance decreased and dry weight accumulation ceased. The outcomes of this study in terms of drought-induced physiological changes, accompanied by a proof-of-concept metabolomics investigation, provide a platform for identifying targets for improved drought-tolerance of the Miscanthus bioenergy crop.

  5. Monitoring and evaluating the physiological changes in the horse with acute abdominal disease.

    PubMed

    Coffman, J R

    1975-03-01

    Initial examination and therapy, and the avoidance of maltreatment are emphasized. Gastric decompression is of prime importance, after which no compound should be administered via stomach tube. Where large amounts of high starch grains are fed, primary acute gastric dilatation must be differentiated from that secondary to small bowel dilatation, by immediate gastric intubation and irrigation of the cardia with lidocaine. If cessation of pain and improvement of peristalsis and general attitude follow, the former state may be assumed. If pain persists and peristalsis does not improve markedly, one should assume small bowel displacement. Rectal examination is helpful in initial evaluation: impactions, inguinal herniation and ileocaecal intussusception may be diagnosed and small bowel displacement suspected. Palpation of one or more distended loops of bowel in the ventral middle third of the abdomen indicates small bowel displacement or ileus and flaccid distension. Distinction by rectal palpation alone is difficult. Palpation of the gas-distended apex of the caecum in the middle third of the abdomen is virtually pathognomonic for 180 degrees rotation of the large bowel. Abdominal paracentesis yielding true sanguineous effusion indicates a necrotizing segment of the bowel. If negative, such a segment is absent, or there is an infarcted segment, not yet damaged to the point of leaching whole blood, or the necrotizing segment is outside the peritoneal cavity, i.e., in the thorax, intussuscepted into the caecum, or herniated into the inguinal canal. Recurrent colics frequently may be due to verminous arteritis but the relationship to diet should be investigated. Recurrent colics after grain ingestion with occult blood in the faeces may be due to ulcers; such cases respond well to grain withdrawal. The advantages and disadvantages of phenothiazine-derived tranquillizers are discussed. They are contra-indicated if there is any evidence of circulating volume insufficiency

  6. Impact of acute fat mobilization on the pharmacokinetics of the highly fat distributed compound TAK-357, investigated by physiologically-based pharmacokinetic (PBPK) modeling and simulation.

    PubMed

    Goto, Akihiko; Tagawa, Yoshihiko; Moriya, Yuu; Sato, Sho; Furukawa, Yoshiyuki; Wakabayashi, Takeshi; Tsukamoto, Tetsuya; DeJongh, Joost; van Steeg, Tamara J; Moriwaki, Toshiya; Asahi, Satoru

    2017-03-03

    In a dog toxicokinetic study, an unusual plasma concentration increase of the highly lipophilic compound TAK-357 was observed 2-weeks after termination of a 2-week repeated dosing in one dog with acute body weight loss. The present study investigates the cause of this increase. A physiologically based pharmacokinetic (PBPK) model was constructed using the rat and dog pharmacokinetic data. Using the constructed model, the TAK-357 concentration profile in case of body weight change was simulated. PBPK model-derived simulation suggested that redistribution from adipose tissues to plasma due to loss of body fat caused the observed concentration increase of TAK-357 in dog plasma. The analysis demonstrates that the disposition of a highly lipophilic and fat-distributed compound can be affected by acute changes in adipose tissue mass. PBPK modeling and simulation proved to be efficient tools for quantitative hypothesis testing of apparently atypical PK phenomena resulting from acute physiological changes.

  7. Ethylene and the Regulation of Physiological and Morphological Responses to Nutrient Deficiencies.

    PubMed

    García, María José; Romera, Francisco Javier; Lucena, Carlos; Alcántara, Esteban; Pérez-Vicente, Rafael

    2015-09-01

    To cope with nutrient deficiencies, plants develop both morphological and physiological responses. The regulation of these responses is not totally understood, but some hormones and signaling substances have been implicated. It was suggested several years ago that ethylene participates in the regulation of responses to iron and phosphorous deficiency. More recently, its role has been extended to other deficiencies, such as potassium, sulfur, and others. The role of ethylene in so many deficiencies suggests that, to confer specificity to the different responses, it should act through different transduction pathways and/or in conjunction with other signals. In this update, the data supporting a role for ethylene in the regulation of responses to different nutrient deficiencies will be reviewed. In addition, the results suggesting the action of ethylene through different transduction pathways and its interaction with other hormones and signaling substances will be discussed.

  8. Ethylene and the Regulation of Physiological and Morphological Responses to Nutrient Deficiencies

    PubMed Central

    García, María José; Romera, Francisco Javier; Lucena, Carlos; Alcántara, Esteban; Pérez-Vicente, Rafael

    2015-01-01

    To cope with nutrient deficiencies, plants develop both morphological and physiological responses. The regulation of these responses is not totally understood, but some hormones and signaling substances have been implicated. It was suggested several years ago that ethylene participates in the regulation of responses to iron and phosphorous deficiency. More recently, its role has been extended to other deficiencies, such as potassium, sulfur, and others. The role of ethylene in so many deficiencies suggests that, to confer specificity to the different responses, it should act through different transduction pathways and/or in conjunction with other signals. In this update, the data supporting a role for ethylene in the regulation of responses to different nutrient deficiencies will be reviewed. In addition, the results suggesting the action of ethylene through different transduction pathways and its interaction with other hormones and signaling substances will be discussed. PMID:26175512

  9. Rain influences the physiological and metabolic responses to exercise in hot conditions.

    PubMed

    Ito, Ryo; Yamashita, Naoyuki; Suzuki, Eiko; Matsumoto, Takaaki

    2015-01-01

    Outdoor exercise often proceeds in rainy conditions. However, the cooling effects of rain on human physiological responses have not been systematically studied in hot conditions. The present study determined physiological and metabolic responses using a climatic chamber that can precisely simulate hot, rainy conditions. Eleven healthy men ran on a treadmill at an intensity of 70% VO2max for 30 min in the climatic chamber at an ambient temperature of 33°C in the presence (RAIN) or absence (CON) of 30 mm · h(-1) of precipitation and a headwind equal to the running velocity of 3.15 ± 0.19 m · s(-1). Oesophageal temperature, mean skin temperature, heart rate, rating of perceived exertion, blood parameters, volume of expired air and sweat loss were measured. Oesophageal and mean skin temperatures were significantly lower from 5 to 30 min, and heart rate was significantly lower from 20 to 30 min in RAIN than in CON (P < 0.05 for all). Plasma lactate and epinephrine concentrations (30 min) and sweat loss were significantly lower (P < 0.05) in RAIN compared with CON. Rain appears to influence physiological and metabolic responses to exercise in heat such that heat-induced strain might be reduced.

  10. Impacts of mixtures of herbicides on molecular and physiological responses of the European flounder Platichthys flesus.

    PubMed

    Evrard, Estérine; Marchand, Justine; Theron, Michaël; Pichavant-Rafini, Karine; Durand, Gaël; Quiniou, Louis; Laroche, Jean

    2010-09-01

    The widespread use of pesticides results in a growing contamination of the aquatic environment. The effects of (1) a simple mixture of a glyphosate-based formulation and AMPA (Aminomethylphosphonic acid--a primary metabolite of glyphosate) and of (2) a more complex mixture of herbicides (glyphosate/AMPA/mecoprop/acetochlor/2,4D) were explored on the molecular and physiological responses of the European flounder Platichthys flesus, considering a long-term and environmentally realistic contamination. Molecular responses were identified using suppression subtractive hybridization on liver samples: the level of gene transcription was significantly different between contaminated fishes vs control ones for 532 sequences, after a 62-day contamination. Among them, 222 sequences were identified by homology with data-based sequences; they encoded several metabolic pathways including: methionine and lipid metabolism, immunity, protein regulation, coagulation and energetic metabolism. Expression pattern of nine transcripts in the liver was confirmed by real-time PCR. The molecular study underlined that potential markers of liver injury were expressed for both mixtures, in particular betaine homocysteine methyl transferase and chemotaxin. Physiological responses were analysed considering blood parameters and condition factor; after the two months contamination period; no significant physiological difference was detected between contaminated and control fish.

  11. Physiological, biochemical, and psychological responses to environmental survival training in the Royal Australian Air Force.

    PubMed

    Chester, Annalise L; Edwards, Andrew M; Crowe, Melissa; Quirk, Frances

    2013-07-01

    Military environmental survival training (EST) is designed and considered to evoke significant stressors to military personnel in preparation for combat-like scenarios. The aim of this study was to observe and report selected physiological, biochemical, psychological, and performance responses to this intense 15-day program of Royal Australian Air Force (RAAF) EST. Fourteen RAAF participants undertook the EST course. Physiological and psychological responses were collected across the 15 days across outcomes: (1) biochemical markers (blood lactate, interlukin-6, and creatine kinase), (2) performance and anthropometric indices (vertical jump, body mass), and (3) psychological questionnaires profile of mood states, depression anxiety stress scale, Kessler-10 etc.). Creatine kinase concentration increased significantly from baseline to day 5 (p < 0.05) and thereafter remained elevated for the remaining 10 days of EST (128%; p < 0.01). Vertical jump (-10%; p < 0.01) and body mass (-8%; p < 0.01) both decreased across 15 days of EST, while there were no significant change in interlukin-6. Negative psychological responses were observed for mood (p < 0.01), depression (p < 0.05), anxiety (p < 0.01), and stress (p < 0.01) following the EST course. This case study showed the RAAF EST course imposed significant physiological and psychological stress as observed from markers of muscle damage, deterioration in physical performance, substantial weight loss, negative mood, and psychological distress.

  12. Serum Response Factor Mediated Gene Activity in Physiological and Pathological Processes of Neuronal Motility

    PubMed Central

    Knöll, Bernd

    2011-01-01

    In recent years, the transcription factor serum response factor (SRF) was shown to contribute to various physiological processes linked to neuronal motility. The latter include cell migration, axon guidance, and, e.g., synapse function relying on cytoskeletal dynamics, neurite outgrowth, axonal and dendritic differentiation, growth cone motility, and neurite branching. SRF teams up with myocardin related transcription factors (MRTFs) and ternary complex factors (TCFs) to mediate cellular actin cytoskeletal dynamics and the immediate-early gene (IEG) response, a bona fide indicator of neuronal activation. Herein, I will discuss how SRF and cofactors might modulate physiological processes of neuronal motility. Further, potential mechanisms engaged by neurite growth promoting molecules and axon guidance cues to target SRF’s transcriptional machinery in physiological neuronal motility will be presented. Of note, altered cytoskeletal dynamics and rapid initiation of an IEG response are a hallmark of injured neurons in various neurological disorders. Thus, SRF and its MRTF and TCF cofactors might emerge as a novel trio modulating peripheral and central axon regeneration. PMID:22164132

  13. Psychoneurometric Operationalization of Threat Sensitivity: Relations with Clinical Symptom and Physiological Response Criteria

    PubMed Central

    Yancey, James R.; Venables, Noah C.; Patrick, Christopher J.

    2015-01-01

    The NIMH RDoC initiative calls for the incorporation of neurobiological approaches and findings into conceptions of mental health problems through a focus on biobehavioral constructs investigated across multiple domains of measurement (units of analysis). Though the constructs in the RDoC system are characterized in ‘process terms’ (i.e., as functional concepts with brain and behavioral referents), these constructs can also be framed as dispositions (i.e., as dimensions of variation in biobehavioral functioning across individuals). Focusing on one key RDoC construct, acute threat or ‘fear’, the current paper illustrates a construct-oriented psychoneurometric strategy to operationalizing this construct in individual-difference terms—as threat sensitivity (THT+). Utilizing data from 454 adult participants, we demonstrate empirically that: 1) a scale measure of THT+ design to tap general fear/fearlessness predicts effectively to relevant clinical problems (i.e., fear disorder symptoms), 2) this scale measure shows reliable associations with physiological indices of acute reactivity to aversive visual stimuli, and 3) a cross-domain factor reflecting the intersection of scale and physiological indicators of THT+ predicts effectively to both clinical and neurophysiological criterion measures. Results illustrate how the psychoneurometric approach can be used to create a dimensional index of a biobehavioral trait construct, in this case THT+, which can serve as a bridge between phenomena in domains of psychopathology and neurobiology. Implications and future directions are discussed with reference to the RDoC initiative and existing report-based conceptions of psycholological traits. PMID:26877132

  14. Effects of camelina meal supplementation on ruminal forage degradability, performance, and physiological responses of beef cattle.

    PubMed

    Cappellozza, B I; Cooke, R F; Bohnert, D W; Cherian, G; Carroll, J A

    2012-11-01

    Three experiments compared ruminal, physiological, and performance responses of beef steers consuming hay ad libitum and receiving grain-based supplements without (control) or with (CAM) the inclusion of camelina meal. In Exp. 1, 9 steers fitted with ruminal cannulas received CAM (2.04 kg of DM/d; n = 5) or control (2.20 kg of DM/d; n = 4). Steers receiving CAM had reduced (P = 0.01) total DMI and tended to have reduced (P = 0.10) forage DMI compared with control. No treatment effects were detected (P ≥ 0.35) for ruminal hay degradability parameters. In Exp. 2, 14 steers fed CAM (1.52 kg of DM/d; n = 7) or control (1.65 kg of DM/d; n = 7) were assigned to a corticotropin-releasing hormone (CRH; 0.1 μg/kg of BW) and a thyrotropin-releasing hormone (TRH; 0.33 μg/kg of BW) challenge. Steers fed CAM had greater (P < 0.05) serum concentrations of PUFA compared with control before challenges. Upon CRH infusion, plasma haptoglobin concentrations tended (P = 0.10) to be reduced and ceruloplasmin concentrations increased at a lesser rate in CAM steers compared with control (treatment × time; P < 0.01). Upon TRH infusion, no treatment effects were detected (P ≥ 0.55) for serum thyrotropin-stimulating hormone, triiodothyronine, and thyroxine. In Exp. 3, 60 steers were allocated to 20 pens. Pens were assigned randomly to receive CAM (2.04 kg of DM/steer daily; n = 10) or control (2.20 kg of DM/steer daily; n = 10) during preconditioning (PC; d -28 to 0). On d 0, steers were transported for 24 h. Upon arrival, pens were assigned randomly to receive CAM or control during feedlot receiving (FR; d 1 to 29). During PC, CAM steers had reduced (P < 0.01) forage and total DMI, and tended to have reduced (P = 0.10) ADG compared with control. Plasma linolenic acid concentrations increased during PC for CAM steers, but not for control (treatment × day; P = 0.02). During FR, steers fed CAM during PC had reduced (P < 0.01) forage and total DMI, but tended (P = 0.10) to have greater

  15. Effects of flunixin meglumine administration on physiological and performance responses of transported feeder cattle.

    PubMed

    Cooke, R F; Cappellozza, B I; Guarnieri Filho, T A; Bohnert, D W

    2013-11-01

    The objective was to evaluate the effects of flunixin meglumine administration on physiological and performance responses of transported cattle during feedlot receiving. Forty-five Angus × Hereford steers were ranked by BW on d 0 and assigned to 1 of 3 treatments: 1) transport for 1,280 km in a commercial livestock trailer and administration of flunixin meglumine (1.1 mg/kg BW; intravenous) at loading (d 0) and unloading (d 1; FM), 2) transport for 1,280 km in a commercial livestock trailer and administration of 0.9% saline (0.022 mL/kg BW; intravenous) at loading (d 0) and unloading (d 1; TRANS), or 3) no transport and administration of 0.9% saline (0.022 mL/kg BW; intravenous) concurrently with loading (d 0) and unloading (d 1) of FM and TRANS cohorts (CON). Upon arrival and processing for treatment administration on d 1, steers within each treatment were ranked by BW and assigned to 15 feedlot pens (5 pens/treatment, 3 steers/pen). Full BW was recorded before (d -1 and 0) treatment application and at the end of experiment (d 28 and 29) for ADG calculation. Total DMI was evaluated daily from d 1 to 28. Blood samples were collected on d 0 (before treatment administration), 1 (after unloading but before treatment administration), 4, 7, 10, 14, 21, and 28. Body weight shrink from d 0 to 1 was less (P<0.01) in CON vs. FM and TRANS but similar (P=0.94) between TRANS and FM. Mean ADG was greater (P≤0.04) in CON vs. FM and TRANS but similar (P=0.69) between TRANS and FM. No treatment effects were detected on DMI, but CON had greater G:F vs. TRANS (P=0.08) and FM (P=0.02), whereas G:F was similar (P=0.68) between TRANS and FM. Mean plasma cortisol concentrations tended (P≤0.09) to be greater in TRANS vs. FM and CON but was similar (P=0.87) between CON and FM. Plasma NEFA concentrations were greater (P≤0.02) for TRANS and FM vs. CON on d 1 and greater (P≤0.04) for FM vs. TRANS and CON on d 4. Plasma ceruloplasmin concentrations were greater (P≤0.03) for TRANS

  16. Physiological Imaging-Defined, Response-Driven Subvolumes of a Tumor

    SciTech Connect

    Farjam, Reza; Tsien, Christina I.; Feng, Felix Y.; Gomez-Hassan, Diana; Hayman, James A.; Lawrence, Theodore S.; Cao, Yue

    2013-04-01

    Purpose: To develop an image analysis framework to delineate the physiological imaging-defined subvolumes of a tumor in relating to treatment response and outcome. Methods and Materials: Our proposed approach delineates the subvolumes of a tumor based on its heterogeneous distributions of physiological imaging parameters. The method assigns each voxel a probabilistic membership function belonging to the physiological parameter classes defined in a sample of tumors, and then calculates the related subvolumes in each tumor. We applied our approach to regional cerebral blood volume (rCBV) and Gd-DTPA transfer constant (K{sup trans}) images of patients who had brain metastases and were treated by whole-brain radiation therapy (WBRT). A total of 45 lesions were included in the analysis. Changes in the rCBV (or K{sup trans})–defined subvolumes of the tumors from pre-RT to 2 weeks after the start of WBRT (2W) were evaluated for differentiation of responsive, stable, and progressive tumors using the Mann-Whitney U test. Performance of the newly developed metrics for predicting tumor response to WBRT was evaluated by receiver operating characteristic (ROC) curve analysis. Results: The percentage decrease in the high-CBV-defined subvolumes of the tumors from pre-RT to 2W was significantly greater in the group of responsive tumors than in the group of stable and progressive tumors (P<.007). The change in the high-CBV-defined subvolumes of the tumors from pre-RT to 2W was a predictor for post-RT response significantly better than change in the gross tumor volume observed during the same time interval (P=.012), suggesting that the physiological change occurs before the volumetric change. Also, K{sup trans} did not add significant discriminatory information for assessing response with respect to rCBV. Conclusion: The physiological imaging-defined subvolumes of the tumors delineated by our method could be candidates for boost target, for which further development and evaluation

  17. Effect of fluid ingestion on orthostatic responses following acute exercise

    NASA Technical Reports Server (NTRS)

    Davis, J. E.; Fortney, S. M.

    1997-01-01

    Orthostatic tolerance is impaired following an acute bout of exercise. This study examined the effect of fluid ingestion following treadmill exercise in restoring the cardiovascular responses to an orthostatic stress. Five men (age, 29.6 +/- 3.4 yrs) were exposed to a graded lower body negative (LBNP) pressure protocol (0 to -50 mmHg) during euhydration without exercise (C), 20 minutes after exercise dehydration (D), 20 minutes after exercise and fluid ingestion (FI20), and 60 minutes after exercise and fluid ingestion (FI60). Fluid ingestion (mean +/- SE) consisted of water-ingestion equivalent to 50% of the body weight lost during exercise (520 +/- 15 ml). Exercise dehydration resulted in significantly higher heart rates (119 +/- 8 vs 82 +/- 7 bpm), lower systolic blood pressures (95 +/- 1.7 vs 108 +/- 2.3 mmHg), a smaller increase in leg circumference (3.7 +/- 4 vs 6.9 +/- 1.0 mm), and an attenuated increase in total peripheral resistance (2.58 +/- 1.2 vs 4.28 +/- 0.9 mmHg/L/min) at -50 mmHg LBNP compared to the C condition. Fluid ingestion (both 20 and 60), partially restored the heart rate, systolic blood pressure, and total peripheral resistance responses to LBNP, but did not influence the change in leg circumference during LBNP (4 +/- 0.3 for R20 and 2.8 +/- 0.4 mm for R60). These data illustrate the effectiveness of fluid ingestion on improving orthostatic responses following exercise, and suggest that dehydration is a contributing factor to orthostatic intolerance following exercise.

  18. Physiological and Transcriptional Responses of Different Industrial Microbes at Near-Zero Specific Growth Rates.

    PubMed

    Ercan, Onur; Bisschops, Markus M M; Overkamp, Wout; Jørgensen, Thomas R; Ram, Arthur F; Smid, Eddy J; Pronk, Jack T; Kuipers, Oscar P; Daran-Lapujade, Pascale; Kleerebezem, Michiel

    2015-09-01

    The current knowledge of the physiology and gene expression of industrially relevant microorganisms is largely based on laboratory studies under conditions of rapid growth and high metabolic activity. However, in natural ecosystems and industrial processes, microbes frequently encounter severe calorie restriction. As a consequence, microbial growth rates in such settings can be extremely slow and even approach zero. Furthermore, uncoupling microbial growth from product formation, while cellular integrity and activity are maintained, offers perspectives that are economically highly interesting. Retentostat cultures have been employed to investigate microbial physiology at (near-)zero growth rates. This minireview compares information from recent physiological and gene expression studies on retentostat cultures of the industrially relevant microorganisms Lactobacillus plantarum, Lactococcus lactis, Bacillus subtilis, Saccharomyces cerevisiae, and Aspergillus niger. Shared responses of these organisms to (near-)zero growth rates include increased stress tolerance and a downregulation of genes involved in protein synthesis. Other adaptations, such as changes in morphology and (secondary) metabolite production, were species specific. This comparison underlines the industrial and scientific significance of further research on microbial (near-)zero growth physiology.

  19. Physiological responses to repeated stress in individuals with high and low trait resilience.

    PubMed

    Lü, Wei; Wang, Zhenhong; You, Xuqun

    2016-10-01

    This study examined individual differences in trait resilience in physiological recovery from, and physiological habituation to, repeated stress (i.e. public speaking). Eighty-two college students were categorized as either high (n=40) or low (n=42) on trait resilience, based on the scores of the Connor-Davidson Resilience Scale (CD-RISC). Subjective and physiological data were collected from participants across seven laboratory stages: baseline, stress anticipation 1, stress 1, post-stress 1, stress anticipation 2, stress 2, and post-stress 2. Results indicated that high-trait-resilient participants exhibited more complete heart rate (HR), systolic and diastolic blood pressure (SBP, DBP) recovery from the first and second stress anticipation exposures as compared to low-trait-resilient participants. High-trait-resilient participants demonstrated higher resting respiratory sinus arrhythmia (RSA) coupled with more complete RSA recovery from the first and second stress anticipation exposures as compared to their low-trait-resilient counterparts. Moreover, high-trait-resilient participants exhibited pronounced SBP and DBP habituation across two successive stress anticipation exposures, with greater decreases in SBP and DBP reactivity to recurrent stress anticipation as compared to the low-trait-resilient participants. These findings suggest an adaptive physiological response pattern to recurrent stress in high-trait-resilient individuals.

  20. Physiological and Transcriptional Responses of Different Industrial Microbes at Near-Zero Specific Growth Rates

    PubMed Central

    Ercan, Onur; Bisschops, Markus M. M.; Overkamp, Wout; Jørgensen, Thomas R.; Ram, Arthur F.; Smid, Eddy J.; Pronk, Jack T.; Kuipers, Oscar P.

    2015-01-01

    The current knowledge of the physiology and gene expression of industrially relevant microorganisms is largely based on laboratory studies under conditions of rapid growth and high metabolic activity. However, in natural ecosystems and industrial processes, microbes frequently encounter severe calorie restriction. As a consequence, microbial growth rates in such settings can be extremely slow and even approach zero. Furthermore, uncoupling microbial growth from product formation, while cellular integrity and activity are maintained, offers perspectives that are economically highly interesting. Retentostat cultures have been employed to investigate microbial physiology at (near-)zero growth rates. This minireview compares information from recent physiological and gene expression studies on retentostat cultures of the industrially relevant microorganisms Lactobacillus plantarum, Lactococcus lactis, Bacillus subtilis, Saccharomyces cerevisiae, and Aspergillus niger. Shared responses of these organisms to (near-)zero growth rates include increased stress tolerance and a downregulation of genes involved in protein synthesis. Other adaptations, such as changes in morphology and (secondary) metabolite production, were species specific. This comparison underlines the industrial and scientific significance of further research on microbial (near-)zero growth physiology. PMID:26048933

  1. Ocean warming and acidification: Unifying physiological principles linking organism response to ecosystem change?

    NASA Astrophysics Data System (ADS)

    Pörtner, H. O.; Bock, C.; Lannig, G.; Lucassen, M.; Mark, F. C.; Stark, A.; Walther, K.; Wittmann, A.

    2011-12-01

    The effects of ocean warming and acidification on individual species of marine ectothermic animals may be based on some common denominators, i.e. physiological responses that can be assumed to reflect unifying principles, common to all marine animal phyla. Identification of these principles requires studies, which reach beyond the species-specific response, and consider multiple stressors, for example temperature, CO2 or extreme hypoxia. Analyses of response and acclimation include functional traits of physiological performance on various levels of biological organisation, from changes in the transcriptome to patterns of acid-base regulation and whole animal thermal tolerance. Conclusions are substantiated by comparisons of species and phyla from temperate, Arctic and Antarctic ecosystems and also benefit from the interpretation of paleo-patterns based on the use of a unifying physiological concept, suitable to integrate relevant environmental factors into a more comprehensive picture. Studying the differential specialization of animals on climate regimes and their sensitivity to climate leads to improved understanding of ongoing and past ecosystem change and should then support more reliable projections of future scenarios. For example, accumulating CO2 causes disturbances in acid-base status. Resilience to ocean acidification may be reflected in the capacity to compensate for these disturbances or their secondary effects. Ion and pH regulation comprise thermally sensitive active and passive transfer processes across membranes. Specific responses of ion transporter genes and their products to temperature and CO2 were found in fish, crustaceans and bivalves. However, compensation may cause unfavourable shifts in energy budget and beyond that hamper cellular and mitochondrial metabolism, which are directly linked to the animal's aerobic performance window. In crabs, oysters and, possibly, fishes, a narrowing of the thermal window is caused by moderate increases in

  2. Differential physiological and molecular response of barley genotypes to water deficit.

    PubMed

    de Mezer, Mateusz; Turska-Taraska, Anna; Kaczmarek, Zygmunt; Glowacka, Katarzyna; Swarcewicz, Barbara; Rorat, Tadeusz

    2014-07-01

    Changes in physiological parameters (relative water content (RWC), biomass, water use efficiency (WUE), net photosynthetic yield (PN) and quantum yield of PSII (Fv/Fm)), in proline and sugar content, and expression profile of genes reported to be associated with the barley response to water deficit, including LEA genes, NHX1, Hsdr4, BLT101 and genes encoding transcription factors (HvDREB1, HvABF1, HvABI5 and HvZIP1), were analyzed in seedlings of nine barley genotypes subjected to a progressive increase in water deficit. Seedlings of all genotypes wilted when the soil water content (SWC) declined from 65% (control conditions) to 10% (severe drought conditions), but recovered turgor within a few hours of re-watering. However, when severe drought conditions were prolonged for a week, large differences in survival characteristics were observed between genotypes after re-watering. Multivariate analysis of the changes in physiological and molecular characteristics allowed several different homogenous groups within the genotypes to be distinguished, depending on stress intensity. Furthermore, integration between the stress-response traits was found and was shown to vary depending on the genotype and the stress level. Based on analysis of physiological traits and survival characteristics, two barley genotypes with high adaptability to the stress conditions (cv. Saida and breeding line Cam/B1), and two with low adaptability (cv. Express and breeding line Harmal), were identified. In addition, only changes in expression of the genes HvZIP1, encoding a b-ZIP-type transcription factor, and Hsdr4, encoding a protein of unknown function, were shown to be linked with adaptability of barley to water deficit. In summary, physiological and molecular data revealed large, stress-level-dependent differences between the barley cultivars and breeding lines tested in their response to water deficit.

  3. Morpho-Physiological and Proteome Level Responses to Cadmium Stress in Sorghum

    PubMed Central

    Kamal, Abu Hena Mostafa; Kim, Sang-Woo; Oh, Myeong-Won; Lee, Moon-Soon; Chung, Keun-Yook; Xin, Zhanguo; Woo, Sun-Hee

    2016-01-01

    Cadmium (Cd) stress may cause serious morphological and physiological abnormalities in addition to altering the proteome in plants. The present study was performed to explore Cd-induced morpho-physiological alterations and their potential associated mechanisms in Sorghum bicolor leaves at the protein level. Ten-day-old sorghum seedlings were exposed to different concentrations (0, 100, and 150 μM) of CdCl2, and different morpho-physiological responses were recorded. The effects of Cd exposure on protein expression patterns in S. bicolor were investigated using two-dimensional gel electrophoresis (2-DE) in samples derived from the leaves of both control and Cd-treated seedlings. The observed morphological changes revealed that the plants treated with Cd displayed dramatically altered shoot lengths, fresh weights and relative water content. In addition, the concentration of Cd was markedly increased by treatment with Cd, and the amount of Cd taken up by the shoots was significantly and directly correlated with the applied concentration of Cd. Using the 2-DE method, a total of 33 differentially expressed protein spots were analyzed using MALDI-TOF/TOF MS. Of these, treatment with Cd resulted in significant increases in 15 proteins and decreases in 18 proteins. Major changes were absorbed in the levels of proteins known to be involved in carbohydrate metabolism, transcriptional regulation, translation and stress responses. Proteomic results revealed that Cd stress had an inhibitory effect on carbon fixation, ATP production and the regulation of protein synthesis. Our study provides insights into the integrated molecular mechanisms involved in responses to Cd and the effects of Cd on the growth and physiological characteristics of sorghum seedlings. We have aimed to provide a reference describing the mechanisms involved in heavy metal damage to plants. PMID:26919231

  4. Root transcriptome of two contrasting indica rice cultivars uncovers regulators of root development and physiological responses

    PubMed Central

    Singh, Alka; Kumar, Pramod; Gautam, Vibhav; Rengasamy, Balakrishnan; Adhikari, Bijan; Udayakumar, Makarla; Sarkar, Ananda K.

    2016-01-01

    The huge variation in root system architecture (RSA) among different rice (Oryza sativa) cultivars is conferred by their genetic makeup and different growth or climatic conditions. Unlike model plant Arabidopsis, the molecular basis of such variation in RSA is very poorly understood in rice. Cultivars with stable variation are valuable resources for identification of genes involved in RSA and related physiological traits. We have screened for RSA and identified two such indica rice cultivars, IR-64 (OsAS83) and IET-16348 (OsAS84), with stable contrasting RSA. OsAS84 produces robust RSA with more crown roots, lateral roots and root hairs than OsAS83. Using comparative root transcriptome analysis of these cultivars, we identified genes related to root development and different physiological responses like abiotic stress responses, hormone signaling, and nutrient acquisition or transport. The two cultivars differ in their response to salinity/dehydration stresses, phosphate/nitrogen deficiency, and different phytohormones. Differential expression of genes involved in salinity or dehydration response, nitrogen (N) transport, phosphate (Pi) starvation signaling, hormone signaling and root development underlies more resistance of OsAS84 towards abiotic stresses, Pi or N deficiency and its robust RSA. Thus our study uncovers gene-network involved in root development and abiotic stress responses in rice. PMID:28000793

  5. Bears Show a Physiological but Limited Behavioral Response to Unmanned Aerial Vehicles.

    PubMed

    Ditmer, Mark A; Vincent, John B; Werden, Leland K; Tanner, Jessie C; Laske, Timothy G; Iaizzo, Paul A; Garshelis, David L; Fieberg, John R

    2015-08-31

    Unmanned aerial vehicles (UAVs) have the potential to revolutionize the way research is conducted in many scientific fields. UAVs can access remote or difficult terrain, collect large amounts of data for lower cost than traditional aerial methods, and facilitate observations of species that are wary of human presence. Currently, despite large regulatory hurdles, UAVs are being deployed by researchers and conservationists to monitor threats to biodiversity, collect frequent aerial imagery, estimate population abundance, and deter poaching. Studies have examined the behavioral responses of wildlife to aircraft (including UAVs), but with the widespread increase in UAV flights, it is critical to understand whether UAVs act as stressors to wildlife and to quantify that impact. Biologger technology allows for the remote monitoring of stress responses in free-roaming individuals, and when linked to locational information, it can be used to determine events or components of an animal's environment that elicit a physiological response not apparent based on behavior alone. We assessed effects of UAV flights on movements and heart rate responses of free-roaming American black bears. We observed consistently strong physiological responses but infrequent behavioral changes. All bears, including an individual denned for hibernation, responded to UAV flights with elevated heart rates, rising as much as 123 beats per minute above the pre-flight baseline. It is important to consider the additional stress on wildlife from UAV flights when developing regulations and best scientific practices.

  6. Myocardial Creatine Levels Do Not Influence Response to Acute Oxidative Stress in Isolated Perfused Heart

    PubMed Central

    Aksentijević, Dunja; Zervou, Sevasti; Faller, Kiterie M. E.; McAndrew, Debra J.; Schneider, Jurgen E.; Neubauer, Stefan; Lygate, Craig A.

    2014-01-01

    Background Multiple studies suggest creatine mediates anti-oxidant activity in addition to its established role in cellular energy metabolism. The functional significance for the heart has yet to be established, but antioxidant activity could contribute to the cardioprotective effect of creatine in ischaemia/reperfusion injury. Objectives To determine whether intracellular creatine levels influence responses to acute reactive oxygen species (ROS) exposure in the intact beating heart. We hypothesised that mice with elevated creatine due to over-expression of the creatine transporter (CrT-OE) would be relatively protected, while mice with creatine-deficiency (GAMT KO) would fare worse. Methods and Results CrT-OE mice were pre-selected for creatine levels 20–100% above wild-type using in vivo 1H–MRS. Hearts were perfused in isovolumic Langendorff mode and cardiac function monitored throughout. After 20 min equilibration, hearts were perfused with either H2O2 0.5 µM (30 min), or the anti-neoplastic drug doxorubicin 15 µM (100 min). Protein carbonylation, creatine kinase isoenzyme activities and phospho-PKCδ expression were quantified in perfused hearts as markers of oxidative damage and apoptotic signalling. Wild-type hearts responded to ROS challenge with a profound decline in contractile function that was ameliorated by co-administration of catalase or dexrazoxane as positive controls. In contrast, the functional deterioration in CrT-OE and GAMT KO hearts was indistinguishable from wild-type controls, as was the extent of oxidative damage and apoptosis. Exogenous creatine supplementation also failed to protect hearts from doxorubicin-induced dysfunction. Conclusions Intracellular creatine levels do not influence the response to acute ROS challenge in the intact beating heart, arguing against creatine exerting (patho-)physiologically relevant anti-oxidant activity. PMID:25272153

  7. The acute phase response of cod (Gadus morhua L.): expression of immune response genes.

    PubMed

    Audunsdottir, Sigridur S; Magnadottir, Bergljot; Gisladottir, Berglind; Jonsson, Zophonias O; Bragason, Birkir Th

    2012-02-01

    An acute phase response (APR) was experimentally induced in Atlantic cod (Gadus morhua L.) by intramuscular injection of turpentine oil. The change in the expression of immune related genes was monitored in the anterior kidney and the spleen over a period of 7 days. The genes examined were two types of pentraxins, apolipoprotein A1 (ApoA-I), the complement component C3, interleukin-1β (IL-1β), transferrin, cathelicidin, and hepcidin. All genes were constitutively expressed in both organs and their expression amplified by the turpentine injection. A pattern of response was observed both with respect to the organ preference and to the timing of a maximum response. The increased gene expression of the pentraxins, ApoA-I and C3 was restricted to the anterior kidney, the gene expression of IL-1β, cathelicidin, and transferrin increased in both organs, while hepcidin gene expression was only significantly increased in the spleen. The pentraxins and ApoA-I appear to be early mediators of APR in cod, possibly stimulating C3 and IL-1β response, while the antimicrobial peptides may play a minor role. The increase in transferrin gene expression in both organs, and apparent indifference to cortisol release associated with the turpentine injection, suggests that this could be a typical acute phase protein in cod.

  8. Greater Heart Rate Responses to Acute Stress Are Associated with Better Post-Error Adjustment in Special Police Cadets

    PubMed Central

    Yao, Zhuxi; Yuan, Yi; Buchanan, Tony W.; Zhang, Kan; Zhang, Liang; Wu, Jianhui

    2016-01-01

    High-stress jobs require both appropriate physiological regulation and behavioral adjustment to meet the demands of emergencies. Here, we investigated the relationship between the autonomic stress response and behavioral adjustment after errors in special police cadets. Sixty-eight healthy male special police cadets were randomly assigned to perform a first-time walk on an aerial rope bridge to induce stress responses or a walk on a cushion on the ground serving as a control condition. Subsequently, the participants completed a Go/No-go task to assess behavioral adjustment after false alarm responses. Heart rate measurements and subjective reports confirmed that stress responses were successfully elicited by the aerial rope bridge task in the stress group. In addition, greater heart rate increases during the rope bridge task were positively correlated with post-error slowing and had a trend of negative correlation with post-error miss rate increase in the subsequent Go/No-go task. These results suggested that stronger autonomic stress responses are related to better post-error adjustment under acute stress in this highly selected population and demonstrate that, under certain conditions, individuals with high-stress jobs might show cognitive benefits from a stronger physiological stress response. PMID:27428280

  9. Genotypic differences in architectural and physiological responses to water restriction in rose bush

    PubMed Central

    Li-Marchetti, Camille; Le Bras, Camille; Relion, Daniel; Citerne, Sylvie; Huché-Thélier, Lydie; Sakr, Soulaiman; Morel, Philippe; Crespel, Laurent

    2015-01-01

    The shape and, therefore, the architecture of the plant are dependent on genetic and environmental factors such as water supply. The architecture determines the visual quality, a key criterion underlying the decision to purchase an ornamental potted plant. The aim of this study was to analyze genotypic responses of eight rose bush cultivars to alternation of water restriction and re-watering periods, with soil water potential of -20 and -10 kPa respectively. Responses were evaluated at the architectural level through 3D digitalization using six architectural variables and at the physiological level by measuring stomatal conductance, water content, hormones [abscisic acid (ABA), auxin, cytokinins, jasmonic acid, and salicylic acid (SA)], sugars (sucrose, fructose, and glucose), and proline. Highly significant genotype and watering effects were revealed for all the architectural variables measured, as well as genotype × watering interaction, with three distinct genotypic architectural responses to water restriction – weak, moderate and strong – represented by Hw336, ‘Baipome’ and ‘The Fairy,’ respectively. The physiological analysis explained, at least in part, the more moderate architectural response of ‘Baipome’ compared to ‘The Fairy,’ but not that of Hw336 which is an interspecific hybrid. Such physiological responses in ‘Baipome’ could be related to: (i) the maintenance of the stimulation of budbreak and photosynthetic activity during water restriction periods due to a higher concentration in conjugated cytokinins (cCK) and to a lower concentration in SA; (ii) a better resumption of budbreak during the re-watering periods due to a lower concentration in ABA during this period. When associated with the six architectural descriptors, cCK, SA and ABA, which explained the genotypic differences in this study, could be used as selection criteria for breeding programs aimed at improving plant shape and tolerance to water restriction. PMID

  10. Genotypic differences in architectural and physiological responses to water restriction in rose bush.

    PubMed

    Li-Marchetti, Camille; Le Bras, Camille; Relion, Daniel; Citerne, Sylvie; Huché-Thélier, Lydie; Sakr, Soulaiman; Morel, Philippe; Crespel, Laurent

    2015-01-01

    The shape and, therefore, the architecture of the plant are dependent on genetic and environmental factors such as water supply. The architecture determines the visual quality, a key criterion underlying the decision to purchase an ornamental potted plant. The aim of this study was to analyze genotypic responses of eight rose bush cultivars to alternation of water restriction and re-watering periods, with soil water potential of -20 and -10 kPa respectively. Responses were evaluated at the architectural level through 3D digitalization using six architectural variables and at the physiological level by measuring stomatal conductance, water content, hormones [abscisic acid (ABA), auxin, cytokinins, jasmonic acid, and salicylic acid (SA)], sugars (sucrose, fructose, and glucose), and proline. Highly significant genotype and watering effects were revealed for all the architectural variables measured, as well as genotype × watering interaction, with three distinct genotypic architectural responses to water restriction - weak, moderate and strong - represented by Hw336, 'Baipome' and 'The Fairy,' respectively. The physiological analysis explained, at least in part, the more moderate architectural response of 'Baipome' compared to 'The Fairy,' but not that of Hw336 which is an interspecific hybrid. Such physiological responses in 'Baipome' could be related to: (i) the maintenance of the stimulation of budbreak and photosynthetic activity during water restriction periods due to a higher concentration in conjugated cytokinins (cCK) and to a lower concentration in SA; (ii) a better resumption of budbreak during the re-watering periods due to a lower concentration in ABA during this period. When associated with the six architectural descriptors, cCK, SA and ABA, which explained the genotypic differences in this study, could be used as selection criteria for breeding programs aimed at improving plant shape and tolerance to water restriction.

  11. Responses to mineral nutrient availability and heterogeneity in physiologically integrated sedges from contrasting habitats.

    PubMed

    D'Hertefeldt, T; Falkengren-Grerup, U; Jónsdóttir, I S

    2011-05-01

    Clonal plants from poor habitats benefit less from morphologically plastic responses to heterogeneity than plants from more productive sites. In addition, physiological integration has been suggested to either increase or decrease the foraging efficiency of clonal plants. We tested the capacity for biomass production and morphological response in two closely related, rhizomatous species from habitats that differ in resource availability, Carex arenaria (from poor sand dunes) and C. disticha (from nutrient-richer, moister habitats). We expected lower total biomass production and reduced morphological plasticity in C. arenaria, and that both species would produce more ramets in high nutrient patches, either in response to signals transported through physiological integration, or by locally determined responses to nutrient availability. To investigate mineral nutrient heterogeneity, plants were grown in boxes divided into two compartments with homogeneous or heterogeneous supply of high (H) or low (L) nutrient levels, resulting in four treatments, H-H, H-L, L-H and L-L. Both C. arenaria and C. disticha produced similar biomass in high nutrient treatments. C. disticha responded to high nutrients by increased biomass production and branching of the young parts and by altering root:shoot ratio and rhizome lengths, while C. arenaria showed localised responses to high nutrients in terms of local biomass and branch production in high nutrient patches. The results demonstrated that although it has a conservative morphology, C. arenaria responded to nutrient heterogeneity through morphological plasticity. An analysis of costs and benefits of integration on biomass production showed that young ramets of both species benefited significantly from physiological integration, but no corresponding costs were found. This suggests that plants from resource-poor but dynamic habitats like sand dunes respond morphologically to high nutrient patches. The two species responded to nutrient

  12. Cortical activation in response to pure taste stimuli during the physiological states of hunger and satiety.

    PubMed

    Haase, Lori; Cerf-Ducastel, Barbara; Murphy, Claire

    2009-02-01

    This event-related functional magnetic resonance imaging (er-fMRI) study investigated BOLD signal change in response to a series of pure gustatory stimuli that varied in stimulus quality when subjects were hungry and sated with a nutritional pre-load. Group analyses showed significant differences in activation in the hunger minus satiety condition in response to sucrose, caffeine, saccharin, and citric acid within the thalamus, hippocampus, and parahippocampus. When examining the hunger and satiety conditions, activation varied as a function of stimulus, with the majority of the stimuli exhibiting significantly greater activation in the hunger state within the insula, thalamus, and substantia nigra, in contrast to decreased activation in the satiated state within the parahippocampus, hippocampus, amygdala, and anterior cingulate. Region of interest (ROI) analysis revealed two significant interactions, ROI by physiology and ROI by physiology by stimulus. In the satiety condition, the primary (inferior and superior insulae) and secondary (OFC 11 and OFC 47) taste regions exhibited significantly greater brain activation in response to all stimuli than regions involved in processing eating behavior (hypothalamus), affect (amygdala), and memory (hippocampus, parahippocampus and entorhinal cortex). These same regions demonstrated significantly greater activation within the hunger condition than the satiety condition, with the exception of the superior insula. Furthermore, the patterns of activation differed as a function taste stimulus, with greater activation in response to sucrose than to the other stimuli. These differential patterns of activation suggest that the physiological states of hunger and satiety produce divergent activation in multiple brain areas in response to different pure gustatory stimuli.

  13. Acute Responses To Resistance And High Intensity Interval Training In Adolescents.

    PubMed

    Harris, Nigel; Dulson, Deborah; Logan, Greig; Warbrick, Isaac; Merien, Fabrice; Lubans, David

    2016-08-16

    The purpose of this study was to compare the acute physiological responses within and between resistance training (RT) and high intensity interval training (HIIT) matched for time and with comparable effort, in a school setting. Seventeen early adolescents (12.9 ± 0.3 y) performed both RT (2-5 repetitions perceived short of failure at the end of each set) and HIIT (90% of age predicted maximum heart rate), equated for total work set and recovery period durations comprising of 12 'sets' of 30 s work followed by 30 s recovery (total session time 12 min). Variables of interest included oxygen consumption, set and session heart rate (HR) and rate of perceived exertion (RPE), and change in salivary cortisol (SC), salivary alpha amylase (SαA), and blood lactate (BL) from pre- to post-session. Analyses were conducted to determine responses within and between the two different protocols. For both RT and HIIT there were very large increases pre- to post-trial for SC and BL, and only BL increased greater in HIIT (9.1 ± 2.6 mmol·L) than RT (6.8 ± 3.3 mmol·L). Mean set HR for both RT (170 ± 9.1 bpm) and HIIT (179 ± 5.6 bpm) was at least 85% of HR maximum. VO2 over all 12 sets was greater for HIIT (33.8 ± 5.21 mL·kg·min) than RT (24.9 ± 3.23 mL·kg·min). Brief, repetitive, intermittent forays into high, but not supra-maximal intensity exercise utilising either RT or HIIT appeared to be a potent physiological stimulus in adolescents.

  14. Achilles tendon biomechanics in response to acute intense exercise.

    PubMed

    Joseph, Michael F; Lillie, Kurtis R; Bergeron, Daniel J; Cota, Kevin C; Yoon, Joseph S; Kraemer, William J; Denegar, Craig R

    2014-05-01

    Achilles tendinopathy is a common disorder and is more prevalent in men. Although differences in tendon mechanics between men and women have been reported, understanding of tendon mechanics in young active people is limited. Moreover, there is limited understanding of changes in tendon mechanics in response to acute exercise. Our purpose was to compare Achilles tendon mechanics in active young adult men and women at rest and after light and strenuous activity in the form of repeated jumping with an added load. Participants consisted of 17 men and 14 women (18-30 years) who were classified as being at least moderately physically active as defined by the International Physical Activity Questionnaire. Tendon force/elongation measures were obtained during an isometric plantarflexion contraction on an isokinetic dynamometer with simultaneous ultrasound imaging of the Achilles tendon approximate to the soleus myotendinous junction. Data were collected at rest, after a 10-minute treadmill walk, and after a fatigue protocol of 100 toe jumps performed in a Smith machine, with a load equaling 20% of body mass. We found greater tendon elongation, decreased stiffness, and lower Young's modulus only in women after the jumping exercise. Force and stress were not different between groups but decreased subsequent to the jumping exercise bout. In general, women had greater elongation and strain, less stiffness, and a lower Young's modulus during plantarflexor contraction. These data demonstrate differences in tendon mechanics between men and women and suggest a potential protective mechanism explaining the lower incidence of Achilles tendinopathy in women.

  15. Acute sun damage and photoprotective responses in whales.

    PubMed

    Martinez-Levasseur, Laura M; Gendron, Diane; Knell, Rob J; O'Toole, Edel A; Singh, Manuraj; Acevedo-Whitehouse, Karina

    2011-05-22

    Rising levels of ultraviolet radiation (UVR) secondary to ozone depletion are an issue of concern for public health. Skin cancers and intraepidermal dysplasia are increasingly observed in individuals that undergo chronic or excessive sun exposure. Such alterations of skin integrity and function are well established for humans and laboratory animals, but remain unexplored for mammalian wildlife. However, effects are unlikely to be negligible, particularly for species such as whales, whose anatomical or life-history traits force them to experience continuous sun exposure. We conducted photographic and histological surveys of three seasonally sympatric whale species to investigate sunburn and photoprotection. We find that lesions commonly associated with acute severe sun damage in humans are widespread and that individuals with fewer melanocytes have more lesions and less apoptotic cells. This suggests that the pathways used to limit and resolve UVR-induced damage in humans are shared by whales and that darker pigmentation is advantageous to them. Furthermore, lesions increased significantly in time, as would be expected under increasing UV irradiance. Apoptosis and melanocyte proliferation mirror this trend, suggesting that whales are capable of quick photoprotective responses. We conclude that the thinning ozone layer may pose a risk to the health of whales and other vulnerable wildlife.

  16. BCL6 modulation of acute lymphoblastic leukemia response to chemotherapy.

    PubMed

    Slone, William L; Moses, Blake S; Hare, Ian; Evans, Rebecca; Piktel, Debbie; Gibson, Laura F

    2016-04-26

    The bone marrow niche has a significant impact on acute lymphoblastic leukemia (ALL) cell phenotype. Of clinical relevance is the frequency with which quiescent leukemic cells, in this niche, survive treatment and contribute to relapse. This study suggests that marrow microenvironment regulation of BCL6 in ALL is one factor that may be involved in the transition between proliferative and quiescent states of ALL cells. Utilizing ALL cell lines, and primary patient tumor cells we observed that tumor cell BCL6 protein abundance is decreased in the presence of primary human bone marrow stromal cells (BMSC) and osteoblasts (HOB). Chemical inhibition, or shRNA knockdown, of BCL6 in ALL cells resulted in diminished ALL proliferation. As many chemotherapy regimens require tumor cell proliferation for optimal efficacy, we investigated the consequences of constitutive BCL6 expression in leukemic cells during co-culture with BMSC or HOB. Forced chronic expression of BCL6 during co-culture with BMSC or HOB sensitized the tumor to chemotherapy induced cell death. Combination treatment of caffeine, which increases BCL6 expression in ALL cells, with chemotherapy extended the event free survival of mice. These data suggest that BCL6 is one factor, modulated by microenvironment derived cues that may contribute to regulation of ALL therapeutic response.

  17. BCL6 modulation of acute lymphoblastic leukemia response to chemotherapy

    PubMed Central

    Slone, William L.; Moses, Blake S.; Hare, Ian; Evans, Rebecca; Piktel, Debbie; Gibson, Laura F.

    2016-01-01

    The bone marrow niche has a significant impact on acute lymphoblastic leukemia (ALL) cell phenotype. Of clinical relevance is the frequency with which quiescent leukemic cells, in this niche, survive treatment and contribute to relapse. This study suggests that marrow microenvironment regulation of BCL6 in ALL is one factor that may be involved in the transition between proliferative and quiescent states of ALL cells. Utilizing ALL cell lines, and primary patient tumor cells we observed that tumor cell BCL6 protein abundance is decreased in the presence of primary human bone marrow stromal cells (BMSC) and osteoblasts (HOB). Chemical inhibition, or shRNA knockdown, of BCL6 in ALL cells resulted in diminished ALL proliferation. As many chemotherapy regimens require tumor cell proliferation for optimal efficacy, we investigated the consequences of constitutive BCL6 expression in leukemic cells during co-culture with BMSC or HOB. Forced chronic expression of BCL6 during co-culture with BMSC or HOB sensitized the tumor to chemotherapy induced cell death. Combination treatment of caffeine, which increases BCL6 expression in ALL cells, with chemotherapy extended the event free survival of mice. These data suggest that BCL6 is one factor, modulated by microenvironment derived cues that may contribute to regulation of ALL therapeutic response. PMID:27015556

  18. Influence of growth rate on the physiological response of marine Synechococcus to phosphate limitation

    PubMed Central

    Kretz, Cécilia B.; Bell, Doug W.; Lomas, Debra A.; Lomas, Michael W.; Martiny, Adam C.

    2015-01-01

    Phosphate (P) is an important nutrient potentially limiting for primary productivity, yet, we currently know little about the relationship between growth rate and physiological response to P limitation in abundant marine Cyanobacteria. Thus, the aim of this research was to determine how variation in growth rate affected the physiology of marine Synechococcus WH8102 and CC9311 when growing under high N:P conditions. Experiments were carried out in chemostats with a media input N:P of 441 and we estimated the half saturation concentration for growth under P limiting conditions (Ks,p) and cellular C:N:P ratios. The Ks,p values were the lowest measured for any phytoplankton and on par with ambient P concentrations in oligotrophic regions. We also observed that both strains were able draw down P below 3 nM. Both Ks,p and drawdown concentration were lower for the open ocean vs. coastal Synechococcus strain, which may be linked to differences in P acquisition genes in these strains. Cellular C:P and N:P ratios were significantly higher in relation to the Redfield ratio for both Synechococcus strains but we saw no difference in these ratios among growth rates or strains. These results demonstrate that Synechococcus can proliferate under very low P conditions and also that genetically different strains have unique physiological responses to P limitation. PMID:25717321

  19. Physiological response of a spinosad-producing strain saccharopolyspora spinosa to space flight

    NASA Astrophysics Data System (ADS)

    Liu, Zhiheng

    This study explored the physiological response of spinosad-producing strain Saccharopolyspora spinosa to space flight environment. The production strain was carried into space by a manned spaceship, `Shenzhou VII' (Divine Vessel VII) and compared with identical ground control strains. The results showed that space flight could induce a significant response in the phys-iological characteristics of S. spinosa, including change of productivity and morphology. The spinosad yield of the mutants increased more than 95% comparing to the original strains. And in the mutant library, a peculiar morphologic strain, F-200, was found. F-200 produced no spinosad, and was much larger than normal ones and spores were lilac, while the others remain white. During fermentation, the color of the entire broth of F-200 had completely changed to purple, whereas the broth of the ground control Zu8 remained yellow. The results demonstrated that the space flight can induce physiological changes of S. spinosa and could potentially serve as mutagenesis tools to improve commercial-significant microbial metabolites.

  20. Physiological responses to 1000-m ergometer time-trial performance in outrigger canoeing.

    PubMed

    Kerr, Rebecca; Spinks, Warwick; Leicht, Anthony; Sinclair, Wade; Woodside, Louise

    2008-09-01

    Graded exercise tests are commonly used to assess peak physiological capacities of athletes. However, unlike time trials, these tests do not provide performance information. The aim of this study was to examine the peak physiological responses of female outrigger canoeists to a 1000-m ergometer time trial and compare the time-trial performance to two graded exercise tests performed at increments of 7.5 W each minute and 15 W each two minutes respectively. 17 trained female outrigger canoeists completed the time trial on an outrigger canoe ergometer with heart rate (HR), stroke rate, power output, and oxygen consumption (VO2) determined every 15 s. The mean (+/- s) time-trial time was 359 +/- 33 s, with a mean power output of 65 +/- 16 W and mean stroke rate of 56 +/- 4 strokes min(-1). Mean values for peak VO2, peak heart rate, and mean heart rate were 3.17 +/- 0.67 litres min(-1), 177 +/- 11 beats min(-1), and 164 +/- 12 beats min(-1) respectively. Compared with the graded exercise tests, the time-trial elicited similar values for peak heart rate, peak power output, peak blood lactate concentration, and peak VO2. As a time trial is sport-specific and can simultaneously quantify sprint performance and peak physiological responses in outrigger canoeing, it is suggested that a time trial be used by coaches for crew selection as it doubles as a reliable performance measure and a protocol for monitoring peak aerobic capacity of female outrigger canoeists.

  1. Growth and Physiological Responses to Water Depths in Carex schmidtii Meinsh.

    PubMed

    Yan, Hong; Liu, Ruiquan; Liu, Zinan; Wang, Xue; Luo, Wenbo; Sheng, Lianxi

    2015-01-01

    A greenhouse experiment was performed to investigate growth and physiological responses to water depth in completely submerged condition of a wetland plant Carex schmidtii Meinsh., one of the dominant species in the Longwan Crater Lake wetlands (China). Growth and physiological responses of C. schmidtii were investigated by growing under control (non-submerged) and three submerged conditions (5 cm, 15 cm and 25 cm water level). Total biomass was highest in control, intermediate in 5 cm treatment and lowest in the other two submerged treatments. Water depth prominently affected the first-order lateral root to main root mass ratio. Alcohol dehydrogenase (ADH) activity decreased but malondialdehyde (MDA) content increased as water depth increased. The starch contents showed no differences among the various treatments at the end of the experiment. However, soluble sugar contents were highest in control, intermediate in 5 cm and 15 cm treatments and lowest in 25 cm treatment. Our data suggest that submergence depth affected some aspects of growth and physiology of C. schmidtii, which can reduce anoxia damage not only through maintaining the non-elongation strategy in shoot part but also by adjusting biomass allocation to different root orders rather than adjusting root-shoot biomass allocation.

  2. Melatonin entrains free-running blind people according to a physiological dose-response curve.

    PubMed

    Lewy, Alfred J; Emens, Jonathan S; Lefler, Bryan J; Yuhas, Krista; Jackman, Angela R

    2005-01-01

    The specific circadian role proposed for endogenous melatonin production was based on a study of sighted people who took low pharmacological doses (500 microg) of this chemical signal for the "biological night": the magnitude and direction of the induced phase shifts were dependent on what time of day exogenous melatonin was administered and were described by a phase-response curve that turned out to be the opposite of that for light. We now report that lower (physiological) doses of up to 300 microg can entrain (synchronize) free-running circadian rhythms of 10 totally blind subjects that would otherwise drift later each day. The resulting log-linear dose-response curve in the physiological range adds support for a circadian function of endogenous melatonin in humans. Efficacy of exogenous doses in the physiological range are of clinical significance for totally blind people who will need to take melatonin daily over their entire lifetimes in order to remain entrained to the 24 h day. Left untreated, their free-running endocrine, metabolic, behavioral, and sleep/wake cycles can be almost as burdensome as not having vision.

  3. Psycho-Physiological Responses by Listening to Some Sounds from Our Daily Life

    NASA Astrophysics Data System (ADS)

    Sakamoto, H.; Hayashi, F.; Tsujikawa, M.; Sugiura, S.

    1997-08-01

    This study was made to clarify the relationship between mode of identification, mode of emotion and physiological response to noise. Twenty-six subjects, young females, listened to six different daily sounds for 150 s through head phones. The level of sound was 60-61LAcq. The pulse wave and blood pressure were observed, and pulse wave interval, wave height and maximum and minimum blood pressures were measured. Measurements were taken twice once 30 s before listening and again during the final 30 s of listening. The ratio of the latter value to the former value was used as the index for the evaluation of change. Immediately after the listening session, identification of the sound source and emotional response were surveyed via a questionnaire and the sounds were judged as related to comfort or discomfort. In the case of incorrect identification, physiological functions were not seen to change significantly. However, in the case of correct identification, maximum and minimum blood pressures were significantly increased form the pre-listening values. The physiological functions of the discomfort group did not change significantly. In the comfort group, wave height was decreased and blood pressure was significantly elevated.

  4. Meta-analysis of digital game and study characteristics eliciting physiological stress responses.

    PubMed

    van der Vijgh, Benny; Beun, Robbert-Jan; Van Rood, Maarten; Werkhoven, Peter

    2015-08-01

    Digital games have been used as stressors in a range of disciplines for decades. Nonetheless, the underlying characteristics of these stressors and the study in which the stressor was applied are generally not recognized for their moderating effect on the measured physiological stress responses. We have therefore conducted a meta-analysis that analyzes the effects of characteristics of digital game stressors and study design on heart rate, systolic and diastolic blood pressure, in studies carried out from 1976 to 2012. In order to assess the differing quality between study designs, a new scale is developed and presented, coined reliability of effect size. The results show specific and consistent moderating functions of both game and study characteristics, on average accounting for around 43%, and in certain cases up to 57% of the variance found in physiological stress responses. Possible cognitive and physiological processes underlying these moderating functions are discussed, and a new model integrating these processes with the moderating functions is presented. These findings indicate that a digital game stressor does not act as a stressor by virtue of being a game, but rather derives its stressor function from its characteristics and the methodology in which it is used. This finding, together with the size of the associated moderations, indicates the need for a standardization of digital game stressors.

  5. Detecting plant metabolic responses induced by ground shock using hyperspectral remote sensing and physiological contact measurements

    SciTech Connect

    Pickles, W.L.; Cater, G.A.

    1996-12-03

    A series of field experiments were done to determine if ground shock could have induced physiological responses in plants and if the level of the response could be observed. The observation techniques were remote sensing techniques and direct contact physiological measurements developed by Carter for detecting pre-visual plant stress. The remote sensing technique was similar to that used by Pickles to detect what appeared to be ground shock induced plant stress above the 1993 Non Proliferation Experiment`s underground chemical explosion. The experiment was designed to provide direct plant physiological measurements and remote sensing ratio images and from the same plants at the same time. The simultaneous direct and remote sensing measurements were done to establish a ground truth dataset to compare to the results of the hyperspectral remote sensing measurements. In addition, the experiment was designed to include data on what was thought to be the most probable interfering effect, dehydration. The experimental design included investigating the relative magnitude of the shock induced stress effects compared to dehydration effects.

  6. Physiological stress response to loss of social influence and threats to masculinity.

    PubMed

    Taylor, Catherine J

    2014-02-01

    Social influence is an important component of contemporary conceptualizations of masculinity in the U.S. Men who fail to achieve masculinity by maintaining social influence in the presence of other men may be at risk of stigmatization. As such, men should be especially likely to exhibit a stress response to loss of social influence in the presence of other men. This study assesses whether men who lose social influence exhibit more of a stress response than men who gain social influence, using data collected in a laboratory setting where participants were randomly assigned into four-person groups of varying sex compositions. The groups were videotaped working on two problem-solving tasks. Independent raters assessed change in social influence using a well-validated measure borrowed from experimental work in the Status Characteristics Theory tradition. Cortisol is used as a measure of stress response because it is known to increase in response to loss of social esteem. Results show that young men who lose social influence while working with other young men exhibit cortisol response. In contrast women do not exhibit cortisol response to loss of social influence, nor do men working with women. Results are consistent with the hypothesis that loss of social influence in men may be associated with a physiological stress response because maintaining social influence is very important to men while in the presence of other men. This physiological response to loss of social influence underscores the importance to men of achieving masculinity through gaining and maintaining social influence, and avoiding the stigma associated with the failure to do so.

  7. Changes of standard physiological-perceptual markers and circulating MicroRNAs in response to tennis match-play: A case report of two elite players

    PubMed Central

    Baumgart, Christian; Hilberg, Thomas; Freiwald, Jürgen; Wehmeier, Udo Frank

    2016-01-01

    Abstract This study aimed to describe the acute changes of both standard physiological-perceptual markers and circulating microRNAs in response to tennis match-play in a detailed case report. Two elite male baseliners with comparable tennis experience were tested for anthropometric and fitness related variables and played 2 h of match-play on a red-clay court. The changes of standard physiological-perceptual markers including the heart rate, lactate concertation, creatine kinase activity, urea concentration and rating of perceived exertion as well as circulating microRNA-133a, -486 and -126 expression rates were examined at 10 different time-points (i.e., pre, during and up to 24 h post match-play). Player 2 had lower fitness related variables, but a higher heart rate, lactate concentration, creatine kinase activity and rating of perceived exertion during play than player 1. Player 2 showed an increase in all microRNAs (≤3.83-fold), most evident post match-play, whereas player 1 demonstrated a decrease (≤0.41-fold). The time-course in the changes of all standard physiological-perceptual markers was similar in both players, whereas this of the microRNAs was different. It was concluded that the relative changes of the circulating microRNA-133a, -486 and 126 expression rates of both players differed in response to tennis match-play with respect to the experienced physiological-perceptual stress and the underlying fitness level. Therefore, circulating microRNAs can serve as additional biomarkers for tennis exercise physiology and may be assessed together with standard markers to conclude whether key cellular regulatory processes were induced in response to match-play. PMID:28149370

  8. Changes of standard physiological-perceptual markers and circulating MicroRNAs in response to tennis match-play: A case report of two elite players.

    PubMed

    Hoppe, Matthias Wilhelm; Baumgart, Christian; Hilberg, Thomas; Freiwald, Jürgen; Wehmeier, Udo Frank

    2016-06-01

    This study aimed to describe the acute changes of both standard physiological-perceptual markers and circulating microRNAs in response to tennis match-play in a detailed case report. Two elite male baseliners with comparable tennis experience were tested for anthropometric and fitness related variables and played 2 h of match-play on a red-clay court. The changes of standard physiological-perceptual markers including the heart rate, lactate concertation, creatine kinase activity, urea concentration and rating of perceived exertion as well as circulating microRNA-133a, -486 and -126 expression rates were examined at 10 different time-points (i.e., pre, during and up to 24 h post match-play). Player 2 had lower fitness related variables, but a higher heart rate, lactate concentration, creatine kinase activity and rating of perceived exertion during play than player 1. Player 2 showed an increase in all microRNAs (≤3.83-fold), most evident post match-play, whereas player 1 demonstrated a decrease (≤0.41-fold). The time-course in the changes of all standard physiological-perceptual markers was similar in both players, whereas this of the microRNAs was different. It was concluded that the relative changes of the circulating microRNA-133a, -486 and 126 expression rates of both players differed in response to tennis match-play with respect to the experienced physiological-perceptual stress and the underlying fitness level. Therefore, circulating microRNAs can serve as additional biomarkers for tennis exercise physiology and may be assessed together with standard markers to conclude whether key cellular regulatory processes were induced in response to match-play.

  9. Physiological responses of elite junior Australian rules footballers during match-play.

    PubMed

    Veale, James P; Pearce, Alan J

    2009-01-01

    Australian Football (AF) is Australia's major football code. Despite research in other football codes, to date, no data has been published on the physiological responses of AF players during match play. Fifteen athletes (17.28 ± 0.76 yrs) participated in four pre-season matches, sanctioned by Australian Football League (AFL) Victoria, investigating Heart Rate (HR), Blood Lactate (BLa), Core Temperature (Tcore), and Hydration status. Match HR was measured continuously using HR monitors. BLa was measured via finger prick lancet at the end of each quarter of play. Tcore was measured by use of ingestible temperature sensor and measured wirelessly at the end of each quarter of play. Hydration status was measured using refractometry, measuring urine specific gravity, and body weight pre and post-match. Environmental conditions were measured continuously during matches. Results of HR responses showed a high exertion of players in the 85-95% maximum HR range. Elevated mean BLa levels, compared to rest, were observed in all players over the duration of the matches (p = 0.007). Mean Tcore rose 0.68 °C between start and end of matches. Mean USG increased between 0.008 g/ml (p = 0.001) with mean body weight decreasing 1.88 kg (p = 0.001). This study illustrates physiological responses in junior AF players playing in the heat as well as providing physiological data for consideration by AF coaching staff when developing specific training programs. Continued research should consider physiological measurements under varying environments, and at all playing levels of AF, to ascertain full physiological responses during AF matches. Key pointsSpecific conditioning sessions for junior athletes should include high intensity bouts; greater than 85% of heart rate maximum zone.Football anaerobic conditioning activities (e.g. sprint training) should be randomised throughout training sessions to replicate demands of the game (e.g. training in a fatigued state).Coaches and fitness staff

  10. Hormonal and electrolyte responses to acute isohemic volume expansion in unanesthetized rats

    NASA Technical Reports Server (NTRS)

    Chenault, V. M.; Morris, M.; Lynch, C. D.; Maultsby, S. J.; Hutchins, P. M.

    1993-01-01

    This study was undertaken to explore the time course of the metabolic response to isohemic blood volume expansion (30%) in normotensive, unanesthetized Sprague-Dawley rats. Whole blood, drawn from a femoral artery catheter of conscious donor rats, was infused into the jugular vein of recipient rats. Blood samples were drawn from a carotid artery of recipient rats at time points beginning immediately post-volume expansion (IPVE) up through 5 days post-volume expansion (PVE). To characterize the attendant compensatory mechanisms, the plasma concentrations of electrolytes and fluid regulatory hormones were determined. Hematocrit began to raise IPVE and was significantly elevated above control IPVE 20, 30, 40, 60, and 90 min, and 2, 4, 6, 8, 12, and 24 hr PVE. Consistent with our current understanding of the hormonal response to excess volume, atrial natriuretic factor was significantly increased above the prevolume expansion (control) values 0-30 min PVE. Surprisingly, plasma aldosterone levels were significantly increased above control at 20 and 30 min and 6 hr PVE, whereas plasma renin activity was significantly decreased 30-40 min PVE. Plasma sodium was not changed from control values except for a significant increase at 6 hr post-volume expansion. Plasma potassium, osmolality, and arginine vasopressin levels were not altered by the volume expansion. These studies delineate the physiologic time scheme operative in the regulation of fluid volume during acute ischemic volume expansion.

  11. Traces of unconscious mental processes in introspective reports and physiological responses.

    PubMed

    Ivonin, Leonid; Chang, Huang-Ming; Diaz, Marta; Catala, Andreu; Chen, Wei; Rauterberg, Matthias

    2015-01-01

    Unconscious mental processes have recently started gaining attention in a number of scientific disciplines. One of the theoretical frameworks for describing unconscious processes was introduced by Jung as a part of his model of the psyche. This framework uses the concept of archetypes that represent prototypical experiences associated with objects, people, and situations. Although the validity of Jungian model remains an open question, this framework is convenient from the practical point of view. Moreover, archetypes found numerous applications in the areas of psychology and marketing. Therefore, observation of both conscious and unconscious traces related to archetypal experiences seems to be an interesting research endeavor. In a study with 36 subjects, we examined the effects of experiencing conglomerations of unconscious emotions associated with various archetypes on the participants' introspective reports and patterns of physiological activations. Our hypothesis for this experiment was that physiological data may predict archetypes more precisely than introspective reports due to the implicit nature of archetypal experiences. Introspective reports were collected using the Self-Assessment Manikin (SAM) technique. Physiological measures included cardiovascular, electrodermal, respiratory responses and skin temperature of the subjects. The subjects were stimulated to feel four archetypal experiences and four explicit emotions by means of film clips. The data related to the explicit emotions served as a reference in analysis of archetypal experiences. Our findings indicated that while prediction models trained on the collected physiological data could recognize the archetypal experiences with accuracy of 55 percent, similar models built based on the SAM data demonstrated performance of only 33 percent. Statistical tests enabled us to confirm that physiological observations are better suited for observation of implicit psychological constructs like archetypes than

  12. Traces of Unconscious Mental Processes in Introspective Reports and Physiological Responses

    PubMed Central

    Ivonin, Leonid; Chang, Huang-Ming; Diaz, Marta; Catala, Andreu; Chen, Wei; Rauterberg, Matthias

    2015-01-01

    Unconscious mental processes have recently started gaining attention in a number of scientific disciplines. One of the theoretical frameworks for describing unconscious processes was introduced by Jung as a part of his model of the psyche. This framework uses the concept of archetypes that represent prototypical experiences associated with objects, people, and situations. Although the validity of Jungian model remains an open question, this framework is convenient from the practical point of view. Moreover, archetypes found numerous applications in the areas of psychology and marketing. Therefore, observation of both conscious and unconscious traces related to archetypal experiences seems to be an interesting research endeavor. In a study with 36 subjects, we examined the effects of experiencing conglomerations of unconscious emotions associated with various archetypes on the participants’ introspective reports and patterns of physiological activations. Our hypothesis for this experiment was that physiological data may predict archetypes more precisely than introspective reports due to the implicit nature of archetypal experiences. Introspective reports were collected using the Self-Assessment Manikin (SAM) technique. Physiological measures included cardiovascular, electrodermal, respiratory responses and skin temperature of the subjects. The subjects were stimulated to feel four archetypal experiences and four explicit emotions by means of film clips. The data related to the explicit emotions served as a reference in analysis of archetypal experiences. Our findings indicated that while prediction models trained on the collected physiological data could recognize the archetypal experiences with accuracy of 55 percent, similar models built based on the SAM data demonstrated performance of only 33 percent. Statistical tests enabled us to confirm that physiological observations are better suited for observation of implicit psychological constructs like archetypes

  13. Acute responses of American kestrels to methyl parathion and fenvalerate

    USGS Publications Warehouse

    Rattner, B.A.; Franson, J.C.

    1984-01-01

    Physiological and toxicological effects of p.o, methyl parathion (0.375-3.0 mg/kg) or fenvalerate (1000-4000 mg/kg) were examined over a 10 h period in American kestrels (Falco sparverius) maintained in thermoneutral (22?.C) and cold (-5?.C) environments. Methyl parathion was highly toxic (LD50=3.08 mg/kg, 95% confidence limits=2.29-4.l4 mg/kg, producing overt intoxication (abnormal posture, ataxia, paresis), dose-dependent inhibition (26-67%) of brain acetylcholinesterase activity, hyperglycemia, and elevated plasma corticosterone concentration. Transient but pronounced hypothermia was associated with plasma cholinesterase inhibition in excess of 50% (2 h after intubation), although this response was highly variable (plasma ChE inhibition vs. A cloacal temperature, r=-0.60). Fenvalerate, at doses far exceeding those encountered in the environment, caused mild intoxication (irregular head movement) and elevated plasma alanine aminotransferase activity, but did not alter cloacal temperature, plasma activities of CK, U-HBDH, and LDK, or concentrations of corticosterone, glucose, triiodothyronine, and uric acid. Cold exposure intensified methyl parathion toxicity, but did not affect that of fenvalerate. It would thus appear that the organophosphorus insecticide methyl parathion poses far greater hazard than the pyrethroid fenvalerate to raptorial birds.

  14. Stress and adaptation responses to repeated acute acceleration.

    NASA Technical Reports Server (NTRS)

    Burton, R. R.; Smith, A. H.

    1972-01-01

    Study in which groups of adult male chickens (single-comb white leghorn) were exposed daily to acceleration (centrifugation) of 2 or 3 G for 10 min, 1, 4, 8, 12, 16, and 24 hr (continuously), or 0 time (controls). After approximately five months of this intermittent treatment (training), the birds were exposed to continuous accelerations of the same G force (intensity). The degree of stress and adaptation of each bird was determined by survival and relative lymphocyte count criteria. Intermittent training exposures of 2 G developed levels of adaptation in birds directly proportional to the duration of their daily exposure. Intermittent training periods at 3 G, however, produced a physiological deterioration in birds receiving daily exposures of 8 hr or more. Adaptive benefits were found only in the 1- and 4-hr-daily intermittent 3-G exposure groups. Exposure to 3 G produced an immediate stress response as indicated by a low relative lymphocyte count which returned to control (preexposed) values prior to the next daily acceleration period in the 10-min, 1-hr, and 4-hr groups. This daily recovery period from stress appeared to be necessary for adaptation as opposed to deterioration for the more severe environmental (3 G) alteration.

  15. Mitigating Physiological Responses to Layoff Threat: An Experimental Test of the Efficacy of Two Coping Interventions

    PubMed Central

    Probst, Tahira M.; Jiang, Lixin

    2016-01-01

    The purpose of the current study was to assess real-time physiological reactions to the threat of layoffs and to determine whether the use of an emotion-focused vs. problem-focused coping intervention would be more efficacious in attenuating these physiological reactions. A 2 (coping intervention) × 4 (within-subjects time points) mixed experimental design was used to test the hypotheses. Eighty-four undergraduates participated in this laboratory experiment during which their galvanic skin response (GSR) and heart rate (HR) were continuously monitored. Analyses indicate that individuals instructed to utilize an emotion-focused coping strategy experienced a significantly greater decline in their GSR compared to those utilizing the problem-focused coping method. Results suggest organizations conducting layoffs might focus first on dealing with the emotional aftermath of downsizing before focusing on problem-solving tasks, such as resume writing and other traditional outplacement activities. PMID:26999186

  16. Mitigating Physiological Responses to Layoff Threat: An Experimental Test of the Efficacy of Two Coping Interventions.

    PubMed

    Probst, Tahira M; Jiang, Lixin

    2016-03-18

    The purpose of the current study was to assess real-time physiological reactions to the threat of layoffs and to determine whether the use of an emotion-focused vs. problem-focused coping intervention would be more efficacious in attenuating these physiological reactions. A 2 (coping intervention) × 4 (within-subjects time points) mixed experimental design was used to test the hypotheses. Eighty-four undergraduates participated in this laboratory experiment during which their galvanic skin response (GSR) and heart rate (HR) were continuously monitored. Analyses indicate that individuals instructed to utilize an emotion-focused coping strategy experienced a significantly greater decline in their GSR compared to those utilizing the problem-focused coping method. Results suggest organizations conducting layoffs might focus first on dealing with the emotional aftermath of downsizing before focusing on problem-solving tasks, such as resume writing and other traditional outplacement activities.

  17. Effects of rare earth elements and REE-binding proteins on physiological responses in plants.

    PubMed

    Liu, Dongwu; Wang, Xue; Chen, Zhiwei

    2012-02-01

    Rare earth elements (REEs), which include 17 elements in the periodic table, share chemical properties related to a similar external electronic configuration. REEs enriched fertilizers have been used in China since the 1980s. REEs could enter the cell and cell organelles, influence plant growth, and mainly be bound with the biological macromolecules. REE-binding proteins have been found in some plants. In addition, the chlorophyll activities and photosynthetic rate can be regulated by REEs. REEs could promote the protective function of cell membrane and enhance the plant resistance capability to stress produced by environmental factors, and affect the plant physiological mechanism by regulating the Ca²⁺ level in the plant cells. The focus of present review is to describe how REEs and REE-binding proteins participate in the physiological responses in plants.

  18. Degree of extraversion and physiological responses to physical pain and sadness.

    PubMed

    Park, Mi-Sook; Lee, Kyung Hwa; Sohn, Sunju; Eom, Jin-Sup; Sohn, Jin-Hun

    2014-10-01

    Extraversion is a personality frequently discussed as one of the strongest and most consistent factors that relates to individual subjective wellbeing. The goal of this study was to better understand how people with varying degrees of extraversion psychologically and physiologically respond differently to unpleasant circumstances. Emotional responses (e.g., levels of intensity, valence, and arousal) were assessed in determining the sensitivity level to negative stimuli that were specifically designed to provoke physical pain and sadness emotion. Physiological changes (e.g., heart rate (HR), blood volume pulse (BVP), and respiratory sinus arrhythmia (RSA)) were also measured during pain and sadness to observe sympathetic and parasympathetic activities. Our results showed that the degree of extraversion was associated with less unpleasant responses to sadness, less HR responses to both pain and sadness, and greater RSA responses to sadness. The findings suggest that the lower HR reactivity to painful and sad situations and greater RSA reactivity to sad situations in extraversion could be possibly due to increased parasympathetic activity. Additionally, enhanced parasympathetic activity to negative situations may explain an important mechanism underlying the positive connection between extraversion and subjective wellbeing.

  19. Physiological Genomics of Response to Soil Drying in Diverse Arabidopsis Accessions[W][OA

    PubMed Central

    Des Marais, David L.; McKay, John K.; Richards, James H.; Sen, Saunak; Wayne, Tierney; Juenger, Thomas E.

    2012-01-01

    Arabidopsis thaliana, like many species, is characterized by abundant genetic variation. This variation is rapidly being cataloged at the sequence level, but careful dissection of genetic variation in whole-organism responses to stresses encountered in the natural environment are lacking; this functional variation can be exploited as a natural mutant screen to determine gene function. Here, we document physiological and transcriptomic response to soil drying in 17 natural accessions of Arabidopsis. By imposing ecologically realistic stress conditions, we found that acclimation in Arabidopsis involved a strong signature of increased investment in photosynthesis, carbohydrate turnover, and root growth. Our results extend previous work in the Columbia accession suggesting that abscisic acid signaling pathways play an important role in drought stress response. We also identified several mechanisms, including an increase in leaf nitrogen concentration and upregulation of two-component signaling relays, that were common to most natural accessions but had not been identified in studies using only the Columbia accession. Principal component analysis reveals strong correlations between suites of genes and specific physiological responses to stress. The functional variants we identified may represent adaptive mutations in natural habitats and useful variants for agronomic improvement of crop species. PMID:22408074

  20. F response and H reflex analysis of physiological unity of gravity and antigravity muscles in man.

    PubMed

    García, H A; Fisher, M A

    1977-01-01

    Observational differences between reflex (H reflex) and antidromic (F response) activation of segmental motoneurons by a peripheral electrical stimulus are described. In contrast to H reflexes, the percentage of F responses found after a series of stimuli is directly related to the pick-up field of the recording electrode consistent with this response being due to the variable activation of a small fraction of the available motoneuron pool. Despite the differing physiological mechanisms, both F responses and H reflexes can be used to demonstrate similar relative "central excitatory states" for antigravity muscles (i.e. extensors in the lower extremity and flexors in the upper extremity) and their antagonist gravity muscles. H reflexes were elicited not only in their usual location in certain antigravity muscles but also in unusual locations by length/tension changes in agonist and antagonist groups as well as by passive stretch. The data argue for the physiological unity of similarly acting gravity and antigravity muscles as well as supporting a meaningful role of group II afferents in normal segmental motoneuron pool excitability.

  1. Size-dependent physiological responses of shore crabs to single and repeated playback of ship noise.

    PubMed

    Wale, Matthew A; Simpson, Stephen D; Radford, Andrew N

    2013-04-23

    Anthropogenic noise has fundamentally changed the acoustics of terrestrial and aquatic environments, and there is growing empirical evidence that even a single noise exposure can affect behaviour in a variety of vertebrate organisms. Here, we use controlled experiments to investigate how the physiology of a marine invertebrate, the shore crab (Carcinus maenas), is affected by both single and repeated exposure to ship-noise playback. Crabs experiencing ship-noise playback consumed more oxygen, indicating a higher metabolic rate and potentially greater stress, than those exposed to ambient-noise playback. The response to single ship-noise playback was size-dependent, with heavier crabs showing a stronger response than lighter individuals. Repeated exposure to ambient-noise playback led to increased oxygen consumption (probably due to handling stress), whereas repeated exposure to ship-noise playback produced no change in physiological response; explanations include the possibility that crabs exhibited a maximal response on first exposure to ship-noise playback, or that they habituated or become tolerant to it. These results highlight that invertebrates, like vertebrates, may also be susceptible to the detrimental impacts of anthropogenic noise and demonstrate the tractability for more detailed investigations into the effects of this pervasive global pollutant.

  2. Physiological and psychological responses to expressions of emotion and empathy in post-stress communication.

    PubMed

    Ono, Makiko; Fujita, Mizuho; Yamada, Shigeyuki

    2009-01-01

    The effects of communicating during and after expressing emotions and receiving empathy after exposure to stress were investigated for 18 female students (9 pairs). After mental and physical tasks, a subject spoke to a listener about the stress task. In Experiment 1, responses to speaking about negative emotions aroused by the task (the "with emotion" condition) were compared to speaking about only objective facts about the task (the control). In Experiment 2, responses to empathetic reactions from the listener (the "with empathy" condition) were compared to no reaction (the control). Electroencephalograms were recorded, and heart rate variability (HRV) was calculated from electrocardiogram data. Subjective stress was estimated by a visual analog scale. Experiment 1 demonstrated that expressing emotions activated the left temporal region (T3) in the "with emotion" condition. In Experiment 2, physiological responses depended on cognition of different elements of empathy. During communication, feeling that the listener had the same emotion decreased the subject's T3 activity and sympathetic activity balance indicated by HRV. After communication, feeling that the listener understood her emotions decreased bilateral frontal and temporal activity. On the other hand, subjective stress did not differ between conditions in both experiments. These findings indicate that the comfort of having shared a message reduced physiological activity, especially in the "with empathy" condition. Conversely, even in the "with empathy" condition, not sharing a message can result in more discomfort or stress than the control. Sharing might be associated with cognition of the degree of success of communication, which reflected in the physiological responses. In communication, therefore, expressing emotions and receiving empathy did not in themselves reduce stress, and the level of cognition of having shared a message is a key factor in reducing stress.

  3. Contrasting physiological plasticity in response to environmental stress within different cnidarians and their respective symbionts

    NASA Astrophysics Data System (ADS)

    Hoadley, Kenneth D.; Pettay, Daniel. T.; Dodge, Danielle; Warner, Mark E.

    2016-06-01

    Given concerns surrounding coral bleaching and ocean acidification, there is renewed interest in characterizing the physiological differences across the multiple host-algal symbiont combinations commonly found on coral reefs. Elevated temperature and CO2 were used to compare physiological responses within the scleractinian corals Montipora hirsuta ( Symbiodinium C15) and Pocillopora damicornis ( Symbiodinium D1), as well as the corallimorph (a non-calcifying anthozoan closely related to scleractinians) Discosoma nummiforme ( Symbiodinium C3). Several physiological proxies were affected more by temperature than CO2, including photochemistry, algal number and cellular chlorophyll a. Marked differences in symbiont number, chlorophyll and volume contributed to distinctive patterns of chlorophyll absorption among these animals. In contrast, carbon fixation either did not change or increased under elevated temperature. Also, the rate of photosynthetically fixed carbon translocated to each host did not change, and the percent of carbon translocated to the host increased in the corallimorph. Comparing all data revealed a significant negative correlation between photosynthetic rate and symbiont density that corroborates previous hypotheses about carbon limitation in these symbioses. The ratio of symbiont-normalized photosynthetic rate relative to the rate of symbiont-normalized carbon translocation (P:T) was compared in these organisms as well as the anemone, Exaiptasia pallida hosting Symbiodinium minutum, and revealed a P:T close to unity ( D. nummiforme) to a range of 2.0-4.5, with the lowest carbon translocation in the sea anemone. Major differences in the thermal responses across these organisms provide further evidence of a range of acclimation potential and physiological plasticity that highlights the need for continued study of these symbioses across a larger group of host taxa.

  4. Physiological and psychological responses of young males during spring-time walks in urban parks

    PubMed Central

    2014-01-01

    Background It is widely believed that contact with the natural environment can improve physical and mental health. Urban green spaces may provide city residents with these benefits; however, there is a lack of empirical field research on the health benefits of urban parks. Methods This field experiment was performed in May. Seventeen males aged 21.2 ± 1.7 years (mean ± standard deviation) were instructed to walk predetermined 15-minute courses in an urban park and a nearby city area (control). Heart rate and heart rate variability (HRV) were measured to assess physiological responses. The semantic differential (SD) method, Profile of Mood States (POMS), and State-Trait Anxiety Inventory (STAI) were used to measure psychological responses. Results Heart rate was significantly lower while walking in the urban park than while walking in the city street. Furthermore, the urban park walk led to higher parasympathetic nervous activity and lower sympathetic nervous activity compared with the walk through the city street. Subjective evaluations were generally in accordance with physiological reactions, and significantly higher scores were observed for the ‘comfortable’, ‘natural’, and ‘relaxed’ parameters following the urban park walk. After the urban park walk, the score for the ‘vigor’ subscale of the POMS was significantly higher, whereas that for negative feelings such as ‘tension-anxiety’ and ‘fatigue’ was significantly lower. The score for the anxiety dimension of the STAI was also significantly lower after the urban park walk. Conclusions Physiological and psychological results from this field experiment provide evidence for the physiological and psychological benefits of urban green spaces. A brief spring-time walk in an urban park shifted sympathetic/parasympathetic balance and improved mood state. PMID:24887352

  5. Swimming performance and physiological responses to exhaustive exercise in radio-tagged and untagged Pacific lampreys

    USGS Publications Warehouse

    Mesa, M.G.; Bayer, J.M.; Seelye, J.G.

    2003-01-01

    Populations of Pacific lamprey Lampetra tridentata have declined in the Columbia River basin. One factor that may have contributed to this reduction in population size is an excessive use of energy by adult lampreys as they negotiate fishways at dams during spawning migrations. To gain an understanding of the performance capacity of Pacific lampreys, we estimated the critical swimming speed (Ucrit) and documented physiological responses of radio-tagged and untagged adult lampreys exercised to exhaustion. The mean (??SD) Ucrit of untagged lampreys was 86.2 ?? 7.5 cm/s at 15??C, whereas the Ucrit for radio-tagged lampreys was 81.5 ?? 7.0 cm/s, a speed that was significantly lower than that of untagged fish. The physiological responses of tagged and untagged lampreys subjected to exhaustive exercise included decreases in blood pH of 0.3-0.5 units, a 40% decrease in muscle glycogen levels, a 22% increase in hematocrit for untagged fish only, and a 4- to 5-fold increase in muscle and a 40- to 100-fold increase in plasma lactate concentrations. These physiological changes were significant compared with resting control fish and usually returned to resting levels by 1-4 h after fatigue. Our estimates of Ucrit for Pacific lampreys are the first quantitative measures of their swimming performance and suggest that these fish may have difficulty negotiating fishways at dams on the Columbia River, which can have water velocities approaching 2 m/s. Our physiological results indicate that tagged and untagged Pacific lampreys show similar metabolic dysfunction after exhaustive exercise but recover quickly from a single exposure to such a stressor.

  6. Effects of Posture and Stimulus Spectral Composition on Peripheral Physiological Responses to Loud Sounds.

    PubMed

    Koch, Jennifer; Flemming, Jan; Zeffiro, Thomas; Rufer, Michael; Orr, Scott P; Mueller-Pfeiffer, Christoph

    2016-01-01

    In the "loud-tone" procedure, a series of brief, loud, pure-tone stimuli are presented in a task-free situation. It is an established paradigm for measuring autonomic sensitization in posttraumatic stress disorder (PTSD). Successful use of this procedure during fMRI requires elicitation of brain responses that have sufficient signal-noise ratios when recorded in a supine, rather than sitting, position. We investigated the modulating effects of posture and stimulus spectral composition on peripheral psychophysiological responses to loud sounds. Healthy subjects (N = 24) weekly engaged in a loud-tone-like procedure that presented 500 msec, 95 dB sound pressure level, pure-tone or white-noise stimuli, either while sitting or supine and while peripheral physiological responses were recorded. Heart rate, skin conductance, and eye blink electromyographic responses were larger to white-noise than pure-tone stimuli (p's < 0.001, generalized eta squared 0.073-0.076). Psychophysiological responses to the stimuli were similar in the sitting and supine position (p's ≥ 0.082). Presenting white noise, rather than pure-tone, stimuli may improve the detection sensitivity of the neural concomitants of heightened autonomic responses by generating larger responses. Recording in the supine position appears to have little or no impact on psychophysiological response magnitudes to the auditory stimuli.

  7. Effects of Posture and Stimulus Spectral Composition on Peripheral Physiological Responses to Loud Sounds

    PubMed Central

    Koch, Jennifer; Flemming, Jan; Zeffiro, Thomas; Rufer, Michael; Orr, Scott P.; Mueller-Pfeiffer, Christoph

    2016-01-01

    In the “loud-tone” procedure, a series of brief, loud, pure-tone stimuli are presented in a task-free situation. It is an established paradigm for measuring autonomic sensitization in posttraumatic stress disorder (PTSD). Successful use of this procedure during fMRI requires elicitation of brain responses that have sufficient signal-noise ratios when recorded in a supine, rather than sitting, position. We investigated the modulating effects of posture and stimulus spectral composition on peripheral psychophysiological responses to loud sounds. Healthy subjects (N = 24) weekly engaged in a loud-tone-like procedure that presented 500 msec, 95 dB sound pressure level, pure-tone or white-noise stimuli, either while sitting or supine and while peripheral physiological responses were recorded. Heart rate, skin conductance, and eye blink electromyographic responses were larger to white-noise than pure-tone stimuli (p’s < 0.001, generalized eta squared 0.073–0.076). Psychophysiological responses to the stimuli were similar in the sitting and supine position (p’s ≥ 0.082). Presenting white noise, rather than pure-tone, stimuli may improve the detection sensitivity of the neural concomitants of heightened autonomic responses by generating larger responses. Recording in the supine position appears to have little or no impact on psychophysiological response magnitudes to the auditory stimuli. PMID:27583659

  8. A Single Session of Autogenic Training Increases Acute Subjective and Physiological Sexual Arousal in Sexually Functional Women.

    PubMed

    Stanton, Amelia; Meston, Cindy

    2016-07-11

    Heart rate variability (HRV) has recently been associated with female sexual function (Stanton, Lorenz, Pulverman, & Meston, 2015). Below-average HRV was identified as a possible risk factor for sexual arousal dysfunction and overall sexual dysfunction in women. Based on this newly established relationship between HRV and female sexual function, the present study examined the effect of autogenic training to increase HRV on acute physiological and subjective sexual arousal in women. Specifically, vaginal pulse amplitude (VPA), an index of genital sexual arousal, and subjective sexual arousal were assessed in 33 sexually functional women, aged 18 to 27, before and after a short session of autogenic training. Autogenic training, a relaxation technique that restores the balance between the activity of the sympathetic and the parasympathetic branches of the autonomic nervous system, has been shown to significantly increase HRV (Miu, Heilman, & Miclea, 2009). After autogenic training, significant increases in both VPA (p <.05) and subjective sexual arousal (p <.005) were observed. Moreover, change in HRV from pre- to postmanipulation significantly moderated changes in subjective sexual arousal (p <.05) when it was measured continuously during the presentation of the erotic stimulus. This cost-effective, easy-to-administer behavioral intervention may have important implications for increasing sexual arousal in women.

  9. Score for neonatal acute physiology-II and neonatal pain predict corticospinal tract development in premature newborns.

    PubMed

    Zwicker, Jill G; Grunau, Ruth E; Adams, Elysia; Chau, Vann; Brant, Rollin; Poskitt, Kenneth J; Synnes, Anne; Miller, Steven P

    2013-02-01

    Premature infants are at risk for adverse motor outcomes, including cerebral palsy and developmental coordination disorder. The purpose of this study was to examine the relationship of antenatal, perinatal, and postnatal risk factors for abnormal development of the corticospinal tract, the major voluntary motor pathway, during the neonatal period. In a prospective cohort study, 126 premature neonates (24-32 weeks' gestational age) underwent serial brain imaging near birth and at term-equivalent age. With diffusion tensor tractography, mean diffusivity and fractional anisotropy of the corticospinal tract were measured to reflect microstructural development. Generalized estimating equation models examined associations of risk factors on corticospinal tract development. The perinatal risk factor of greater early illness severity (as measured by the Score for Neonatal Acute Physiology-II [SNAP-II]) was associated with a slower rise in fractional anisotropy of the corticospinal tract (P = 0.02), even after correcting for gestational age at birth and postnatal risk factors (P = 0.009). Consistent with previous findings, neonatal pain adjusted for morphine and postnatal infection were also associated with a slower rise in fractional anisotropy of the corticospinal tract (P = 0.03 and 0.02, respectively). Lessening illness severity in the first hours of life might offer potential to improve motor pathway development in premature newborns.

  10. Young children's affective responses to another's distress: dynamic and physiological features.

    PubMed

    Fink, Elian; Heathers, James A J; de Rosnay, Marc

    2015-01-01

    Two descriptive studies set out a new approach for exploring the dynamic features of children's affective responses (sadness and interest-worry) to another's distress. In two samples (N(study1) = 75; N(study2) = 114), Kindergarten children were shown a video-vignette depicting another child in distress and the temporal pattern of spontaneous expressions were examined across the unfolding vignette. Results showed, in both study 1 and 2, that sadness and interest-worry had distinct patterns of elicitation across the events of the vignette narrative and there was little co-occurrence of these affects within a given child. Temporal heart rate changes (study 2) were closely aligned to the events of the vignette and, furthermore, affective responses corresponded to distinctive physiological response profiles. The implications of distinct temporal patterns of elicitation for the meaning of sadness and interest-worry are discussed within the framework of emotion regulation and empathy.

  11. Young Children’s Affective Responses to Another’s Distress: Dynamic and Physiological Features

    PubMed Central

    Fink, Elian; Heathers, James A. J.; de Rosnay, Marc

    2015-01-01

    Two descriptive studies set out a new approach for exploring the dynamic features of children’s affective responses (sadness and interest-worry) to another’s distress. In two samples (Nstudy1 = 75; Nstudy2 = 114), Kindergarten children were shown a video-vignette depicting another child in distress and the temporal pattern of spontaneous expressions were examined across the unfolding vignette. Results showed, in both study 1 and 2, that sadness and interest-worry had distinct patterns of elicitation across the events of the vignette narrative and there was little co-occurrence of these affects within a given child. Temporal heart rate changes (study 2) were closely aligned to the events of the vignette and, furthermore, affective responses corresponded to distinctive physiological response profiles. The implications of distinct temporal patterns of elicitation for the meaning of sadness and interest-worry are discussed within the framework of emotion regulation and empathy. PMID:25874952

  12. [The systemic inflammatory response syndrome correction in acute destructive pancreatitis].

    PubMed

    Agapov, M A; Khoreva, M V; Gorskiĭ, V A

    2011-01-01

    Acute pancreatitis is a disease of variable severity. In which some patients experience mild, self-limited attacks while others manifest a severe, highly morbid, and frequently lethal attack. The exact mechanisms by which diverse etiological factors induce an attack are still unclear. Recent studies have established the role played by inflammatory mediators in the pathogenesis of acute pancreatitis. In our research we have estimated influence of not steroid anti-inflammatory preparation on synthesis pro-and anti-inflammatory Cytokines at healthy donors and at patients with Acute pancreatitis.

  13. Neural and Physiological Responses to a Cold Pressor Challenge in Healthy Adolescents

    PubMed Central

    Richardson, Heidi L.; Macey, Paul M.; Kumar, Rajesh; Valladares, Edwin M.; Woo, Mary A.; Harper, Ronald M.

    2014-01-01

    Abnormal autonomic function is common in pediatric diseases. Assessment of central mechanisms underlying autonomic challenges may reveal vulnerabilities antecedent to system failure. Our objective was to characterize central markers and physiological responses to a cold pressor challenge in normal children as a critical step for establishing such screening. We performed functional magnetic resonance imaging (fMRI), and collected physiological measures during cold application to the foot in 24 healthy adolescents (15.5±0.4 years; 13 male). The protocol included a 120s baseline, 120s right-foot cold water immersion (4°C), and 120s recovery. Analyses included heart rate (HR) cross-correlations with fMRI signals. Cold application increased HR 13% 5-7s after onset, which remained elevated throughout the challenge. Respiratory rate transiently increased (peak 22%), then declined (nadir 12% below baseline), before normalizing at 75s. Cold onset rapidly increased somatosensory cortex and medullary signals, which fell after 25s. Right anterior insular cortex signals increased early, followed after 20s by the left anterior insula, with HR declining 8s later. Amygdalae signals also rose, but signals declined in the posterior cingulate cortex, caudate nucleus, hippocampus, and hypothalamus. Declining signals appeared late in the cerebellar fastigial nuclei (60-120s), and in the pons and thalamus. Somatosensory cortex, fastigial nuclei, and hypothalamic responses were principally left-sided, with bilateral responses elsewhere. Late left anterior insula responses likely underlie the HR decline; the late cerebellar pattern may modulate recovery. The laterality, timing and amplitude of normative responses, and rostral response differentiation indicate the complex integration of adolescent autonomic processing, and provide indices for pathological comparisons. PMID:24105663

  14. Plant growth enhancement and associated physiological responses are coregulated by ethylene and gibberellin in response to harpin protein Hpa1.

    PubMed

    Li, Xiaojie; Han, Bing; Xu, Manyu; Han, Liping; Zhao, Yanying; Liu, Zhilan; Dong, Hansong; Zhang, Chunling

    2014-04-01

    The harpin protein Hpa1 produced by the bacterial blight pathogen of rice induces several growth-promoting responses in plants, activating the ethylene signaling pathway, increasing photosynthesis rates and EXPANSIN (EXP) gene expression levels, and thereby enhancing the vegetative growth. This study was attempted to analyze any mechanistic connections among the above and the role of gibberellin in these responses. Hpa1-induced growth enhancement was evaluated in Arabidopsis, tomato, and rice. And growth-promoting responses were determined mainly as an increase of chlorophyll a/b ratio, which indicates a potential elevation of photosynthesis rates, and enhancements of photosynthesis and EXP expression in the three plant species. In Arabidopsis, Hpa1-induced growth-promoting responses were partially compromised by a defect in ethylene perception or gibberellin biosynthesis. In tomato and rice, compromises of Hpa1-induced growth-promoting responses were caused by a pharmacological treatment with an ethylene perception inhibitor or a gibberellin biosynthesis inhibitor. In the three plant species, moreover, Hpa1-induced growth-promoting responses were significantly impaired, but not totally eliminated, by abolishing ethylene perception or gibberellin synthesis. However, simultaneous nullifications in both ethylene perception and gibberellin biosynthesis almost canceled the full effects of Hpa1 on plant growth, photosynthesis, and EXP2 expression. Theses results suggest that ethylene and gibberellin coregulate Hpa1-induced plant growth enhancement and associated physiological and molecular responses.

  15. Physiological and Proteomic Investigations to Study the Response of Tomato Graft Unions under Temperature Stress

    PubMed Central

    Muneer, Sowbiya; Ko, Chung Ho; Wei, Hao; Chen, Yuze; Jeong, Byoung Ryong

    2016-01-01

    Background Grafting is an established practice for asexual propagation in horticultural and agricultural crops. The study on graft unions has become of interest for horticulturists using proteomic and genomic techniques to observe transfer of genetic material and signal transduction pathways from root to shoot and shoot to root. Another reason to study the graft unions was potentially to observe resistance against abiotic stresses. Using physiological and proteomic analyses, we investigated graft unions (rootstock and scions) of tomato genotypes exposed to standard-normal (23/23 and 25/18°C day/night) and high-low temperatures (30/15°C day/night). Results Graft unions had varied responses to the diverse temperatures. High-low temperature, but not standard-normal temperature, induced the production of reactive oxygen species (ROS) in the form of H2O2 and O2-1 in rootstock and scions. However, the expression of many cell protection molecules was also induced, including antioxidant enzymes and their immunoblots, which also show an increase in their activities such as superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX). The graft interfaces thus actively defend against stress by modifying their physiological and proteomic responses to establish a new cellular homeostasis. As a result, many proteins for cellular defense were regulated in graft unions under diverse temperature, in addition to the regulation of photosynthetic proteins, ion binding/transport proteins, and protein synthesis. Moreover, biomass, hardness, and vascular transport activity were evaluated to investigate the basic connectivity between rootstock and scions. Conclusions Our study provides physiological evidence of the grafted plants’ response to diverse temperature. Most notably, our study provides novel insight into the mechanisms used to adapt the diverse temperature in graft unions (rootstock/scion). PMID:27310261

  16. Comparison of physiological response to cardiopulmonary exercise testing among cancer survivors and healthy controls.

    PubMed

    Klika, Riggs J; Golik, Katharina S; Drum, Scott N; Callahan, Kathleen E; Thorland, William G

    2011-06-01

    Selected physiological responses, including lactate kinetics, to cardiopulmonary exercise testing (CPET) were evaluated among a group of cancer survivors (CS, n = 55) and healthy controls (HC, n = 213). It was uncertain if lactate testing in a group of cancer survivors could provide useful information about training intensity. It was hypothesized that chemotherapy, radiation, surgery, physical inactivity or some combination thereof would alter the normal lactate kinetics (curvilinearity) in the relationship of lactate concentration versus power. Physiologic responses of CS (heart rate, blood pressure, O(2) saturation, RPE, lactate, VO(2peak), and peak power) during cycle ergometry were compared to HC. Comparisons (t tests and Chi-square) were made between the groups and shape of lactate plots were analyzed for determination of a breakpoint. Multiple logistical regressions were then utilized to identify factors related to the inability to determine lactate breakpoints. Lactate breakpoints were common to all but one HC whereas among the CS there was a small subset of subjects (n = 5) who did not show a lactate breakpoint. Group differences indicated that female CS were significantly older, had greater BMI's, and lower work capacity than HC. Males CS had significantly lower work capacity than HC. Multiple logistical regression analyses, in all instances, yielded no statistically significant models predictive of the inability to determine a lactate breakpoint. In this sample of CS and HC, physiological responses and lactate kinetics during CPET were similar while work capacity among the CS was lower. Because lactate breakpoints were found, lactate threshold could be determined for all but a few individuals. For those working with CS, CPET with ECG monitoring and lactate threshold measures should be considered for those wishing for precise and safe training intensities.

  17. Transcriptomic Changes Drive Physiological Responses to Progressive Drought Stress and Rehydration in Tomato

    PubMed Central

    Iovieno, Paolo; Punzo, Paola; Guida, Gianpiero; Mistretta, Carmela; Van Oosten, Michael J.; Nurcato, Roberta; Bostan, Hamed; Colantuono, Chiara; Costa, Antonello; Bagnaresi, Paolo; Chiusano, Maria L.; Albrizio, Rossella; Giorio, Pasquale; Batelli, Giorgia; Grillo, Stefania

    2016-01-01

    Tomato is a major crop in the Mediterranean basin, where the cultivation in the open field is often vulnerable to drought. In order to adapt and survive to naturally occurring cycles of drought stress and recovery, plants employ a coordinated array of physiological, biochemical, and molecular responses. Transcriptomic studies on tomato responses to drought and subsequent recovery are few in number. As the search for novel traits to improve the genetic tolerance to drought increases, a better understanding of these responses is required. To address this need we designed a study in which we induced two cycles of prolonged drought stress and a single recovery by rewatering in tomato. In order to dissect the complexity of plant responses to drought, we analyzed the physiological responses (stomatal conductance, CO2 assimilation, and chlorophyll fluorescence), abscisic acid (ABA), and proline contents. In addition to the physiological and metabolite assays, we generated transcriptomes for multiple points during the stress and recovery cycles. Cluster analysis of differentially expressed genes (DEGs) between the conditions has revealed potential novel components in stress response. The observed reduction in leaf gas exchanges and efficiency of the photosystem PSII was concomitant with a general down-regulation of genes belonging to the photosynthesis, light harvesting, and photosystem I and II category induced by drought stress. Gene ontology (GO) categories such as cell proliferation and cell cycle were also significantly enriched in the down-regulated fraction of genes upon drought stress, which may contribute to explain the observed growth reduction. Several histone variants were also repressed during drought stress, indicating that chromatin associated processes are also affected by drought. As expected, ABA accumulated after prolonged water deficit, driving the observed enrichment of stress related GOs in the up-regulated gene fractions, which included transcripts

  18. Physiological and transcriptional responses and cross protection of Lactobacillus plantarum ZDY2013 under acid stress.

    PubMed

    Huang, Renhui; Pan, Mingfang; Wan, Cuixiang; Shah, Nagendra P; Tao, Xueying; Wei, Hua

    2016-02-01

    Acid tolerance responses (ATR) in Lactobacillus plantarum ZDY2013 were investigated at physiological and molecular levels. A comparison of composition of cell membrane fatty acids (CMFA) between acid-challenged and unchallenged cells showed that acid adaptation evoked a significantly higher percentage of saturated fatty acids and cyclopropane fatty acids in acid-challenged than in unchallenged cells. In addition, reverse transcription-quantitative PCR analysis in acid-adapted cells at different pH values (ranging from 3.0 to 4.0) indicated that several genes were differently regulated, including those related to proton pumps, amino acid metabolism, sugar metabolism, and class I and class III stress response pathways. Expression of genes involved in fatty acid synthesis and production of alkali was significantly upregulated. Upon exposure to pH 4.5 for 2 h, a higher survival rate (higher viable cell count) of Lactobacillus plantarum ZDY2013 was achieved following an additional challenge to 40 mM hydrogen peroxide for 60 min, but no difference in survival rate of cells was found with further challenge to heat, ethanol, or salt. Therefore, we concluded that the physiological and metabolic changes of acid-treated cells of Lactobacillus plantarum ZDY2013 help the cells resist damage caused by acid, and further initiated global response signals to bring the whole cell into a state of defense to other stress factors, especially hydrogen peroxide.

  19. Profiling the physiological and molecular response to sulfonamidic drug in Procambarus clarkii.

    PubMed

    Nicosia, Aldo; Celi, Monica; Vazzana, Mirella; Damiano, Maria Alessandra; Parrinello, Nicolò; D'Agostino, Fabio; Avellone, Giuseppe; Indelicato, Serena; Mazzola, Salvatore; Cuttitta, Angela

    2014-11-01

    Sulfamethoxazole (SMZ) is one of the most widely employed sulfonamides. Because of the widespread use of SMZ, a considerable amount is indeed expected to be introduced into the environment. The cytotoxicity of SMZ relies mainly on arylhydroxylamine metabolites (S-NOH) of SMZ and it is associated with the production of reactive oxygen species (ROS). There is limited information about the toxic potential of SMZ at the cellular and molecular levels, especially in aquatic and/or non-target organisms. In the present study, the red swamp crayfish (Procambarus clarkii), being tolerant to extreme environmental conditions and resistant to disease, was used as a model organism to profile the molecular and physiological response to SMZ. Haemolymphatic-immunological parameters such as glucose serum levels and total haemocyte counts were altered; moreover, a significant increase in Hsp70 plasma levels was detected for the first time. Variations at the transcriptional level of proinflammatory genes (cyclooxygenase-1, COX 1, and cyclooxygenase-2, COX 2), antioxidant enzymes (glutathione-S-transferase, GST and manganese superoxide dismutase MnSOD), stress response and Fenton reaction inhibitor genes (heat-shock protein 70 HSP70, metallothionein, MT and ferritin, FT) were evaluated, and alterations in the canonical gene expression patterns emerged. Considering these results, specific mechanisms involved in maintaining physiological homeostasis and adaptation in response to perturbations are suggested.

  20. Do infants find snakes aversive? Infants' physiological responses to "fear-relevant" stimuli.

    PubMed

    Thrasher, Cat; LoBue, Vanessa

    2016-02-01

    In the current research, we sought to measure infants' physiological responses to snakes-one of the world's most widely feared stimuli-to examine whether they find snakes aversive or merely attention grabbing. Using a similar method to DeLoache and LoBue (Developmental Science, 2009, Vol. 12, pp. 201-207), 6- to 9-month-olds watched a series of multimodal (both auditory and visual) stimuli: a video of a snake (fear-relevant) or an elephant (non-fear-relevant) paired with either a fearful or happy auditory track. We measured physiological responses to the pairs of stimuli, including startle magnitude, latency to startle, and heart rate. Results suggest that snakes capture infants' attention; infants showed the fastest startle responses and lowest average heart rate to the snakes, especially when paired with a fearful voice. Unexpectedly, they also showed significantly reduced startle magnitude during this same snake video plus fearful voice combination. The results are discussed with respect to theoretical perspectives on fear acquisition.

  1. Adaptive response of vascular endothelial cells to an acute increase in shear stress frequency.

    PubMed

    Zhang, Ji; Friedman, Morton H

    2013-09-15

    Local shear stress sensed by arterial endothelial cells is occasionally altered by changes in global hemodynamic parameters, e.g., heart rate and blood flow rate, as a result of normal physiological events, such as exercise. In a recently study (41), we demonstrated that during the adaptive response to increased shear magnitude, porcine endothelial cells exhibited an unique phenotype featuring a transient increase in permeability and the upregulation of a set of anti-inflammatory and antioxidative genes. In the present study, we characterize the adaptive response of these cells to an increase in shear frequency, another important hemodynamic parameter with implications in atherogenesis. Endothelial cells were preconditioned by a basal-level sinusoidal shear stress of 15 ± 15 dyn/cm(2) at 1 Hz, and the frequency was then elevated to 2 Hz. Endothelial permeability increased slowly after the frequency step-up, but the increase was relatively small. Using microarrays, we identified 37 genes that are sensitive to the frequency step-up. The acute increase in shear frequency upregulates a set of cell-cycle regulation and angiogenesis-related genes. The overall adaptive response to the increased frequency is distinctly different from that to a magnitude step-up. However, consistent with the previous study, our data support the notion that endothelial function during an adaptive response is different than that of fully adapted endothelial cells. Our studies may also provide insights into the beneficial effects of exercise on vascular health: transient increases in frequency may facilitate endothelial repair, whereas similar increases in shear magnitude may keep excessive inflammation and oxidative stress at bay.

  2. Acute metabolic response to fasted and postprandial exercise

    PubMed Central

    de Lima, Filipe Dinato; Correia, Ana Luiza Matias; Teixeira, Denilson da Silva; da Silva Neto, Domingos Vasco; Fernandes, Ítalo Sávio Gonçalves; Viana, Mário Boratto Xavier; Petitto, Mateus; da Silva Sampaio, Rodney Antônio; Chaves, Sandro Nobre; Alves, Simone Teixeira; Dantas, Renata Aparecida Elias; Mota, Márcio Rabelo

    2015-01-01

    The aim of this study was to analyze the acute metabolic response to exercise in fasting and postprandial. For this, ten individuals were submitted to an incremental treadmill test, with an initial speed of 5 and 1 km/h increments every minute, with no inclination, and a body composition assessment. After this 1st day, all volunteers were submitted to two experimental procedures (fasting and postprandial), with an aerobic exercise performed for 36 minutes at 65% of maximal oxygen consumption. At postprandial procedure, all subjects ingested a breakfast containing 59.3 g of carbohydrate (76.73%), 9.97 g of protein (12.90%), 8.01 g of lipids (10.37%), with a total energy intake of 349.17 kcal. An analysis of plasma concentration of triglycerides, lactate, and glucose was performed in two stages: before and after exercise. The Shapiro–Wilk test was used to verify the normality of the data. For analysis of glucose concentration, plasma lactate, and triglycerides, we used a repeated measures analysis of variance factorial 2×2, with Bonferroni multiple comparison test. The significance level of P<0.05 was adopted. The results indicated a maintenance level of glucose at fasting and a decrease in glucose concentration at postprandial exercise. Both conditions increase plasma lactate. Triglycerides also increased in the two experimental conditions; however, after exercise fasting, the increase was significantly higher than in the postprandial exercise. These data suggest that both exercises could increase plasma lactate and triglycerides. However, exercise performed in fasting condition decreases glucose concentration and increases triglycerides, even more than postprandial exercise. PMID:26316800

  3. Pathophysiological role of the acute inflammatory response during acetaminophen hepatotoxicity

    SciTech Connect

    Cover, Cathleen; Liu Jie; Farhood, Anwar; Malle, Ernst; Waalkes, Michael P.; Bajt, Mary Lynn; Jaeschke, Hartmut . E-mail: jaeschke@email.arizona.edu

    2006-10-01

    Neutrophils are recruited into the liver after acetaminophen (AAP) overdose but the pathophysiological relevance of this acute inflammatory response remains unclear. To address this question, we compared the time course of liver injury, hepatic neutrophil accumulation and inflammatory gene mRNA expression for up to 24 h after treatment with 300 mg/kg AAP in C3Heb/FeJ and C57BL/6 mice. Although there was no relevant difference in liver injury (assessed by the increase of plasma alanine aminotransferase activities and the areas of necrosis), the number of neutrophils and the expression of several pro-inflammatory genes (e.g., tumor necrosis factor-{alpha}, interleukin-1{beta} and macrophage inflammatory protein-2) was higher in C3Heb/FeJ than in C57BL/6 mice. In contrast, the expression of the anti-inflammatory genes interleukin-10 and heme oxygenase-1 was higher in C57BL/6 mice. Despite substantial hepatic neutrophil accumulation, none of the liver sections from both strains stained positive for hypochlorite-modified proteins, a specific marker for a neutrophil-induced oxidant stress. In addition, treatment with the NADPH oxidase inhibitors diphenyleneiodonium chloride or apocynin or the anti-neutrophil antibody Gr-1 did not protect against AAP hepatotoxicity. Furthermore, although intercellular adhesion molecule-1 (ICAM-1) was previously shown to be important for neutrophil extravasation and tissue injury in several models, ICAM-1-deficient mice were not protected against AAP-mediated liver injury. Together, these data do not support the hypothesis that neutrophils aggravate liver injury induced by AAP overdose.

  4. Physiological and behavioural responses to weaning conflict in free-ranging primate infants

    PubMed Central

    Mandalaywala, Tara M.; Higham, James P.; Heistermann, Michael; Parker, Karen J.; Maestripieri, Dario

    2014-01-01

    Weaning, characterized by maternal reduction of resources, is both psychologically and energetically stressful to mammalian offspring. Despite the importance of physiology in this process, previous studies have reported only indirect measures of weaning stress from infants, because of the difficulties of collecting physiological measures from free-ranging mammalian infants. Here we present some of the first data on the relationship between weaning and energetic and psychological stress in infant mammals. We collected data on 47 free-ranging rhesus macaque infants on Cayo Santiago, Puerto Rico, showing that faecal glucocorticoid metabolite (fGCM) concentrations were directly related to the frequency of maternal rejection, with fGCM concentrations increasing as rates of rejection increased. Infants with higher fGCM concentrations also engaged in higher rates of mother following, and mother following was associated with increased time on the nipple, suggesting that infants that experienced greater weaning-related stress increased their efforts to maintain proximity and contact with their mothers. Infants experiencing more frequent rejection uttered more distress vocalizations when being rejected; however, there was no relationship between rates of distress vocalizations and fGCM concentrations, suggesting a disassociation between behavioural and physiological stress responses to weaning. Elevated glucocorticoid concentrations during weaning may function to mobilize energy reserves and prepare the infant for continued maternal rejection and shortage of energetic resources. PMID:25431499

  5. Beneficial physiological and performance responses to a month of restricted energy intake in healthy overweight women.

    PubMed

    Buffenstein, R; Karklin, A; Driver, H S

    2000-02-01

    Changes in mood, performance, cortisol, and physiological variables with a month-long energy restricting diet (3.347 MJ/day) were studied in nine overweight (mean mass 71.2 +/- 8 kg; body mass index 26.1 +/- 2.8 kg/m(2)), healthy premenopausal (age 20-36 years) women. Measurements were taken in the 2 weeks before the diet (baseline) and again in the final 2 weeks of the diet to attenuate menstrual cycle differences. A reduction in energy intake and concomitant weight loss (5.80 +/- 1.65 kg) were accompanied by a significant decline in systolic blood pressure (5.4%), heart rate (7.6%), and cortisol concentration (13.6%). Fatigue and vigour on the Profile of Mood States (POMS) questionnaire were adversely affected; however, subjective assessments of mood, concentration, temperature sensitivity, appetite, and sleep quality using visual analogue scales, were not significantly altered during the month-long period of energy restriction. Motor performance, as assessed by hand-eye coordination, improved with both a reduction in mean reaction time and improved accuracy in response to visual stimuli. The very low-energy diet appeared to be neither physiologically nor psychologically stressful. Beneficial effects were evident with a reduction in BMI, reduced risk of cardiovascular stress, improved motor performance, and a decline in physiological stress with dieting success.

  6. Physiological and Molecular Responses of Lactuca sativa to Colonization by Salmonella enterica Serovar Dublin▿

    PubMed Central

    Klerks, M. M.; van Gent-Pelzer, M.; Franz, E.; Zijlstra, C.; van Bruggen, A. H. C.

    2007-01-01

    This paper describes the physiological and molecular interactions between the human-pathogenic organism Salmonella enterica serovar Dublin and the commercially available mini Roman lettuce cv. Tamburo. The association of S. enterica serovar Dublin with lettuce plants was first determined, which indicated the presence of significant populations outside and inside the plants. The latter was evidenced from significant residual concentrations after highly efficient surface disinfection (99.81%) and fluorescence microscopy of S. enterica serovar Dublin in cross sections of lettuce at the root-shoot transition region. The plant biomass was reduced significantly compared to that of noncolonized plants upon colonization with S. enterica serovar Dublin. In addition to the physiological response, transcriptome analysis by cDNA amplified fragment length polymorphism analysis also provided clear differential gene expression profiles between noncolonized and colonized lettuce plants. From these, generally and differentially expressed genes were selected and identified by sequence analysis, followed by reverse transcription-PCR displaying the specific gene expression profiles in time. Functional grouping of the expressed genes indicated a correlation between colonization of the plants and an increase in expressed pathogenicity-related genes. This study indicates that lettuce plants respond to the presence of S. enterica serovar Dublin at physiological and molecular levels, as shown by the reduction in growth and the concurrent expression of pathogenicity-related genes. In addition, it was confirmed that Salmonella spp. can colonize the interior of lettuce plants, thus potentially imposing a human health risk when processed and consumed. PMID:17513585

  7. Ambient temperature: a factor affecting performance and physiological response of broiler chickens

    NASA Astrophysics Data System (ADS)

    Donkoh, A.

    1989-12-01

    An experiment was conducted to elucidate the influence of four constant ambient temperatures (20°, 25°, 30° and 35°C) on the performance and physiological reactions of male commercial broiler chicks from 3 to 7 weeks of age. A 12 h light-dark cycle was operated, while relative humidity and air circulation were not controlled. Exposure of broiler chickens to the 20°, 25°, 30° and 35°C treatments showed highly significant ( P<0.0001) depression in growth rate, food intake and efficiency of food utilization, and a significant increase in water consumption for the 30° and 35°C groups. Mortality was, however, not affected by the temperature treatments. Changes in physiological status, such as increased rectal temperatures, decreased concentration of red blood cells, haemoglobin, haematocrit, and total plasma protein were observed in birds housed in the higher temperature (30° and 35°C) environments. Moreover, in these broiler chickens, there was an increased blood glucose concentration and a decreased thyroid gland weight. These results indicate that continuous exposure of broiler chickens to high ambient temperatures markedly affects their performance and physiological response.

  8. Physiological stress responses, fecal marking behavior, and reproduction in wild European pine martens (Martes martes).

    PubMed

    Barja, Isabel; Silván, Gema; Martínez-Fernández, Leticia; Illera, Juan Carlos

    2011-03-01

    The relationship among physiological stress responses, fecal marking behavior, and reproduction in male and female European pine martens was investigated. Between July 2004 and June 2007, 145 fresh fecal samples were collected in a protected area of northwest Spain. Fecal DNA was used for specific identification by using the polymerase chain reaction-restriction fragment length polymorphism technique. Glucocorticoids (cortisol) and sex steroid hormones (P, progesterone; E, estradiol; T, testosterone) were quantified by enzyme immunoassays. Sex was assigned according to concentrations of T+P+E and the T/P ratio. Fecal cortisol concentrations were higher in males than in females. Feces with a presumptive marking function (on conspicuous substrates, above ground level, and/or in latrines) had higher mean levels of cortisol than those that were on inconspicuous substrates and/or at ground level, for both males and females. Fecal mark density was highest in spring, when mean levels of fecal cortisol were more elevated. Therefore, the higher physiological stress levels in females could be due to female physiological state (late-term pregnancy and lactation), competition for resources connected to birth, or food resources for offspring rearing. In males, the increase could be due to higher male competition for access to females during pro-estrus and estrus. Our results suggest that scent marking in European pine martens is related to reproduction and is involved in intersexual and intrasexual communication.

  9. Responses of corn physiology and yield to six agricultural practices over three years in middle Tennessee

    PubMed Central

    Yu, Chih-Li; Hui, Dafeng; Deng, Qi; Wang, Junming; Reddy, K. Chandra; Dennis, Sam

    2016-01-01

    Different agricultural practices may have substantial impacts on crop physiology and yield. However, it is still not entirely clear how multiple agricultural practices such as tillage, biochar and different nutrient applications could influence corn physiology and yield. We conducted a three-year field experiment to study the responses of corn physiology, yield, and soil respiration to six different agricultural practices. The six treatments included conventional tillage (CT) or no tillage (NT), in combination with nitrogen type (URAN or chicken litter) and application method, biochar, or denitrification inhibitor. A randomized complete block design was applied with six replications. Leaf photosynthetic rate, transpiration, plant height, leaf area index (LAI), biomass, and yield were measured. Results showed that different agricultural practices had significant effects on plant leaf photosynthesis, transpiration, soil respiration, height, and yield, but not on LAI and biomass. The average corn yield in the NT-URAN was 10.03 ton/ha, 28.9% more than in the CT-URAN. Compared to the NT-URAN, the NT-biochar had lower soil respiration and similar yield. All variables measured showed remarkable variations among the three years. Our results indicated that no tillage treatment substantially increased corn yield, probably due to the preservation of soil moisture during drought periods. PMID:27272142

  10. NMR-Based Metabonomic Analysis of Physiological Responses to Starvation and Refeeding in the Rat.

    PubMed

    Serrano-Contreras, José I; García-Pérez, Isabel; Meléndez-Camargo, María E; Zepeda, L Gerardo

    2016-09-02

    Starvation is a postabsorptive condition derived from a limitation on food resources by external factors. Energy homeostasis is maintained under this condition by using sources other than glucose via adaptive mechanisms. After refeeding, when food is available, other adaptive processes are linked to energy balance. However, less has been reported about the physiological mechanisms present as a result of these conditions, considering the rat as a supraorganism. Metabolic profiling using (1)H nuclear magnetic resonance spectroscopy was used to characterize the physiological metabolic differences in urine specimens collected under starved, refed, and recovered conditions. In addition, because starvation induced lack of faecal production and not all animals produced faeces during refeeding, 24 h pooled faecal water samples were also analyzed. Urinary metabolites upregulated by starvation included 2-butanamidoacetate, 3-hydroxyisovalerate, ketoleucine, methylmalonate, p-cresyl glucuronide, p-cresyl sulfate, phenylacetylglycine, pseudouridine, creatinine, taurine, and N-acetyl glycoprotein, which were related to renal and skeletal muscle function, β-oxidation, turnover of proteins and RNA, and host-microbial interactions. Food-derived metabolites, including gut microbial cometabolites, and tricarboxylic acid cycle intermediates were upregulated under refed and recovered conditions, which characterized anabolic urinary metabotypes. The upregulation of creatine and pantothenate indicated an absorptive state after refeeding. Fecal short chain fatty acids, 3-(3-hydroxyphenyl)propionate, lactate, and acetoin provided additional information about the combinatorial metabolism between the host and gut microbiota. This investigation contributes to allow a deeper understanding of physiological responses associated with starvation and refeeding.

  11. Physiological and emotional responses of disabled children to therapeutic clowns: a pilot study.

    PubMed

    Kingsnorth, Shauna; Blain, Stefanie; McKeever, Patricia

    2011-01-01

    This pilot study examined the effects of Therapeutic Clowning on inpatients in a pediatric rehabilitation hospital. Ten disabled children with varied physical and verbal expressive abilities participated in all or portions of the data collection protocol. Employing a mixed-method, single-subject ABAB study design, measures of physiological arousal, emotion and behavior were obtained from eight children under two conditions-television exposure and therapeutic clown interventions. Four peripheral autonomic nervous system (ANS) signals were recorded as measures of physiological arousal; these signals were analyzed with respect to measures of emotion (verbal self reports of mood) and behavior (facial expressions and vocalizations). Semistructured interviews were completed with verbally expressive children (n = 7) and nurses of participating children (n = 13). Significant differences among children were found in response to the clown intervention relative to television exposure. Physiologically, changes in ANS signals occurred either more frequently or in different patterns. Emotionally, children's (self) and nurses' (observed) reports of mood were elevated positively. Behaviorally, children exhibited more positive and fewer negative facial expressions and vocalizations of emotion during the clown intervention. Content and themes extracted from the interviews corroborated these findings. The results suggest that this popular psychosocial intervention has a direct and positive impact on hospitalized children. This pilot study contributes to the current understanding of the importance of alternative approaches in promoting well-being within healthcare settings.

  12. Physiological and Emotional Responses of Disabled Children to Therapeutic Clowns: A Pilot Study

    PubMed Central

    Kingsnorth, Shauna; Blain, Stefanie; McKeever, Patricia

    2011-01-01

    This pilot study examined the effects of Therapeutic Clowning on inpatients in a pediatric rehabilitation hospital. Ten disabled children with varied physical and verbal expressive abilities participated in all or portions of the data collection protocol. Employing a mixed-method, single-subject ABAB study design, measures of physiological arousal, emotion and behavior were obtained from eight children under two conditions—television exposure and therapeutic clown interventions. Four peripheral autonomic nervous system (ANS) signals were recorded as measures of physiological arousal; these signals were analyzed with respect to measures of emotion (verbal self reports of mood) and behavior (facial expressions and vocalizations). Semistructured interviews were completed with verbally expressive children (n = 7) and nurses of participating children (n = 13). Significant differences among children were found in response to the clown intervention relative to television exposure. Physiologically, changes in ANS signals occurred either more frequently or in different patterns. Emotionally, children's (self) and nurses' (observed) reports of mood were elevated positively. Behaviorally, children exhibited more positive and fewer negative facial expressions and vocalizations of emotion during the clown intervention. Content and themes extracted from the interviews corroborated these findings. The results suggest that this popular psychosocial intervention has a direct and positive impact on hospitalized children. This pilot study contributes to the current understanding of the importance of alternative approaches in promoting well-being within healthcare settings. PMID:21799690

  13. Physiological responses and tolerance threshold to cadmium contamination in Eremochloa ophiuroides.

    PubMed

    Liu, Yiming; Wang, Kai; Xu, Peixian; Wang, Zhaolong

    2012-01-01

    Plant tolerance is one of the preconditions in soil phytoremediation. The physiological responses and tolerance threshold of centipedegrass (Eremochloa ophiuroides) were investigated under eight different Cd concentrations (0, 60, 120, 180, 240, 300, 360, and 420 mg Cd kg(-1)) in a sand culture system. The results showed that turf quality, leaf relative water content (RWC), leaf electrolyte leakage (EL), leaf osmotic potential did not show significant changes under 180 mg Cd kg(-1) compared with the control, and relative growth rate (RGR), turf density, leaf chlorophyll content, photochemical efficiency (Fv/Fm) did not show significant changes under 240 mg Cd kg(-1) compared with the control throughout the whole experiment. Regression analysis was used to determine the threshold Cd concentrations for each physiological parameter and the most sensitive parameter occurred by RWC of 197 mg Cd kg(-1) which was chose as Cd tolerance threshold in centipedegrass because under this concentration the plant did not show any significant difference with the control in all growth and physiological parameters measured in this experiment. The phytoextration rate of centipedegrass reached 0.87% in 36 d under 180 mg Cd kg(-10 treatment.

  14. Responses of corn physiology and yield to six agricultural practices over three years in middle Tennessee.

    PubMed

    Yu, Chih-Li; Hui, Dafeng; Deng, Qi; Wang, Junming; Reddy, K Chandra; Dennis, Sam

    2016-06-07

    Different agricultural practices may have substantial impacts on crop physiology and yield. However, it is still not entirely clear how multiple agricultural practices such as tillage, biochar and different nutrient applications could influence corn physiology and yield. We conducted a three-year field experiment to study the responses of corn physiology, yield, and soil respiration to six different agricultural practices. The six treatments included conventional tillage (CT) or no tillage (NT), in combination with nitrogen type (URAN or chicken litter) and application method, biochar, or denitrification inhibitor. A randomized complete block design was applied with six replications. Leaf photosynthetic rate, transpiration, plant height, leaf area index (LAI), biomass, and yield were measured. Results showed that different agricultural practices had significant effects on plant leaf photosynthesis, transpiration, soil respiration, height, and yield, but not on LAI and biomass. The average corn yield in the NT-URAN was 10.03 ton/ha, 28.9% more than in the CT-URAN. Compared to the NT-URAN, the NT-biochar had lower soil respiration and similar yield. All variables measured showed remarkable variations among the three years. Our results indicated that no tillage treatment substantially increased corn yield, probably due to the preservation of soil moisture during drought periods.

  15. Near-UV radiation acts as a beneficial factor for physiological responses in cucumber plants.

    PubMed

    Mitani-Sano, Makiko; Tezuka, Takafumi

    2013-11-05

    Effects of near-UV radiation on the growth and physiological activity of cucumber plants were investigated morphologically, physiologically and biochemically using 3-week-old seedlings grown under polyvinyl chloride films featuring transmission either above 290 nm or above 400 nm in growth chambers. The hypocotyl length and leaf area of cucumber seedlings were reduced but the thickness of leaves was enhanced by near-UV radiation, due to increased upper/lower epidermis thickness, palisade parenchyma thickness and volume of palisade parenchyma cells. Photosynthetic and respiratory activities were also promoted by near-UV radiation, associated with general enhancement of physiological/biochemical responses. Particularly, metabolic activities in the photosynthetic system of chloroplasts and the respiratory system of mitochondria were analyzed under the conditions of visible light with and without near-UV radiation. For example, the activities of NAD(P)-dependent enzymes such as glyceraldehyde-3-phosphate dehydrogenase (G3PDH) in chloroplasts and isocitrate dehydrogenase (ICDH) in mitochondria were elevated, along with levels of pyridine nucleotides (nicotinamide coenzymes) [NAD(H) and NADP(H)] and activity of NAD kinase (NADP forming enzyme). Taken together, these data suggest that promotion of cucumber plant growth by near-UV radiation involves activation of carbon and nitrogen metabolism in plants. The findings of this research showed that near-UV radiation reaching the Earth's surface is a beneficial factor for plant growth.

  16. Metabonomic studies on the physiological effects of acute and chronic psychological stress in Sprague-Dawley rats.

    PubMed

    Teague, Claire R; Dhabhar, Firdaus S; Barton, Richard H; Beckwith-Hall, Bridgette; Powell, Jonathan; Cobain, Mark; Singer, Burton; McEwen, Bruce S; Lindon, John C; Nicholson, Jeremy K; Holmes, Elaine

    2007-06-01

    The biochemical effects of acute and chronic psychological stress have been investigated in male Sprague-Dawley rats using a combination of 1H NMR spectral analysis of plasma and conventional hematological analyses. Animals were subjected to 35 consecutive days of 6-h sessions of stress, and following a 9 day break, were stressed for a further 6-h period. Plasma samples were collected at 0, 1, 3, and 6 h on days 1, 9, 21, 35, and 44, measured using 600 MHz 1H NMR spectroscopy, and analyzed by Principal Components Analysis. Time-dependent biochemical effects of psychological stress on a range of endogenous metabolites were evident and were correlated with the intensity of the stress response as defined by corticosterone and hematological parameters. Following acute stress, increases in the levels of glucose and ketone bodies, and decreases in the levels of acetate, alanine, isoleucine, lactate, leucine, valine, and lipoproteins, were observed. Chronic stress-induced increases in plasma levels of alanine, lactate (day 9), and leucine, valine, and choline (day 44) and decreases in acetate (day 9) and lipoprotein concentrations were observed. Positive correlations between plasma corticosterone level and glucose and glycerol, and between plasma lipoprotein concentrations and hemoglobin levels, were established using Projection to Latent Structures (PLS) analysis. This study indicates the potential of using NMR-based metabonomic strategies for the characterization of endogenous metabolic perturbations induced by psychological stressors and lifestyle choices.

  17. The Effects of Caffeine Supplementation on Physiological Responses to Submaximal Exercise in Endurance-Trained Men

    PubMed Central

    2016-01-01

    Objectives The aim of this study was to evaluate the effects of caffeine on physiological responses to submaximal exercise, with a focus on blood lactate concentration ([BLa]). Methods Using a randomised, single-blind, crossover design; 16 endurance-trained, male cyclists (age: 38 ± 8 years; height: 1.80 ± 0.05 m; body mass: 76.6 ± 7.8 kg; V˙O2max: 4.3 ± 0.6 L∙min-1) completed four trials on an electromagnetically-braked cycle ergometer. Each trial consisted of a six-stage incremental test (3 minute stages) followed by 30 minutes of passive recovery. One hour before trials 2–4, participants ingested a capsule containing 5 mg∙kg-1 of either caffeine or placebo (maltodextrin). Trials 2 and 3 were designed to evaluate the effects of caffeine on various physiological responses during exercise and recovery. In contrast, Trial 4 was designed to evaluate the effects of caffeine on [BLa] during passive recovery from an end-exercise concentration of 4 mmol∙L-1. Results Relative to placebo, caffeine increased [BLa] during exercise, independent of exercise intensity (mean difference: 0.33 ± 0.41 mmol∙L-1; 95% likely range: 0.11 to 0.55 mmol∙L-1), but did not affect the time-course of [BLa] during recovery (p = 0.604). Caffeine reduced ratings of perceived exertion (mean difference: 0.5 ± 0.7; 95% likely range: 0.1 to 0.9) and heart rate (mean difference: 3.6 ± 4.2 b∙min-1; 95% likely range: 1.3 to 5.8 b∙min-1) during exercise, with the effect on the latter dissipating as exercise intensity increased. Supplement × exercise intensity interactions were observed for respiratory exchange ratio (p = 0.004) and minute ventilation (p = 0.034). Conclusions The results of the present study illustrate the clear, though often subtle, effects of caffeine on physiological responses to submaximal exercise. Researchers should be aware of these responses, particularly when evaluating the physiological effects of various experimental interventions. PMID:27532605

  18. Short-term physiological responses of wild and hatchery-produced red drum during angling

    USGS Publications Warehouse

    Gallman, E.A.; Isely, J.J.; Tomasso, J.R.; Smith, T.I.J.

    1999-01-01

    Serum cortisol concentrations, plasma glucose concentrations, plasma lactate concentrations, and plasma osmolalities increased in red drum Sciaenops ocellatus (26.0-65.5 cm total length) during angling in estuarine waters (17-33 g/L salinity, 21-31??C). Angling time varied from as fast as possible (10 s) to the point when fish ceased resisting (up to 350 s). The increases in the physiological characteristics were similar in wild and hatchery-produced fish. This study indicates that hatchery-produced red drum may be used in catch-and-release studies to simulate the responses of wild fish.

  19. Human Physiological Responses to Cycle Ergometer Leg Exercise During +Gz Acceleration

    NASA Technical Reports Server (NTRS)

    Chou, J. L.; Stad, N. J.; Barnes, P. R.; Leftheriotis, G. P. N.; Arndt, N. F.; Simonson, S.; Greenleaf, J. E.

    1998-01-01

    Spaceflight and bed-rest deconditioning decrease maximal oxygen uptake (aerobic power), strength, endurance capacity, and orthostatic tolerance. In addition to extensive use of muscular exercise conditioning as a countermeasure for the reduction in aerobic power (VO(sub 2max)), stimuli from some form of +Gz acceleration conditioning may be necessary to attenuate the orthostatic intolerance component of this deconditioning. Hypothesis: There will be no significant difference in the physiological responses (oxygen uptake, heart rate, ventilation, or respiratory exchange ratio) during supine exercise with moderate +Gz acceleration.

  20. Emotional Responses during Reading: Physiological Responses Predict Real-Time Reading Comprehension

    ERIC Educational Resources Information Center

    Daley, Samantha G.; Willett, John B.; Fischer, Kurt W.

    2014-01-01

    This study investigated the relationship between emotional responses and reading performance in middle-school students. Although a large number of prior studies have investigated the relationship between emotion and reading, those studies have concentrated primarily on relatively static and distal measures of emotion. In this research, we measured…

  1. Dissimilar Physiological and Perceptual Responses Between Sprint Interval Training and High-Intensity Interval Training.

    PubMed

    Wood, Kimberly M; Olive, Brittany; LaValle, Kaylyn; Thompson, Heather; Greer, Kevin; Astorino, Todd A

    2016-01-01

    High-intensity interval training (HIIT) and sprint interval training (SIT) elicit similar cardiovascular and metabolic adaptations vs. endurance training. No study, however, has investigated acute physiological changes during HIIT vs. SIT. This study compared acute changes in heart rate (HR), blood lactate concentration (BLa), oxygen uptake (VO2), affect, and rating of perceived exertion (RPE) during HIIT and SIT. Active adults (4 women and 8 men, age = 24.2 ± 6.2 years) initially performed a VO2max test to determine workload for both sessions on the cycle ergometer, whose order was randomized. Sprint interval training consisted of 8 bouts of 30 seconds of all-out cycling at 130% of maximum Watts (Wmax). High-intensity interval training consisted of eight 60-second bouts at 85% Wmax. Heart rate, VO2, BLa, affect, and RPE were continuously assessed throughout exercise. Repeated-measures analysis of variance revealed a significant difference between HIIT and SIT for VO2 (p < 0.001), HR (p < 0.001), RPE (p = 0.03), and BLa (p = 0.049). Conversely, there was no significant difference between regimens for affect (p = 0.12). Energy expenditure was significantly higher (p = 0.02) in HIIT (209.3 ± 40.3 kcal) vs. SIT (193.5 ± 39.6 kcal). During HIIT, subjects burned significantly more calories and reported lower perceived exertion than SIT. The higher VO2 and lower BLa in HIIT vs. SIT reflected dissimilar metabolic perturbation between regimens, which may elicit unique long-term adaptations. If an individual is seeking to burn slightly more calories, maintain a higher oxygen uptake, and perceive less exertion during exercise, HIIT is the recommended routine.

  2. Physiological responses in swine treated with water containing sodium bicarbonate as a prophylactic for gastric ulcers.

    PubMed

    Cole, J T; Argenzio, R A; Eisemann, J H

    2004-09-01

    Maintenance of gastric pH above 4.0 aids the prevention of bile acid-mediated ulcerative damage to the pars esophageal tissue in pigs. One means of doing so is the addition of buffering compounds, such as sodium bicarbonate, to the water supply; however, any potential physiological effect of buffer consumption has yet to be determined. Experiment 1 tested the acute effects of buffer addition to the water supply on systemic acid-base and electrolyte balance in swine (BW 40.7 +/- 3.0 kg). Consumption of water calculated to a 200 mOsm solution with sodium bicarbonate for 24 h increased (P < 0.05) blood Na+, HCO3(-), and pCO2, although these effects were all within physiologically tolerable levels. Urine pH and Na+ excretion increased (P < 0.001) following the consumption of NaHCO3, with Na+ concentration almost threefold higher in treated pigs compared with controls. Experiment 2 determined the chronic systemic effects of buffer consumption by measuring blood and urine variables, with pigs consuming NaHCO3-treated water throughout. Water consumption increased (P < 0.001) during buffer consumption, although intake levels remained within normal ranges. Blood pH levels were not affected by long-term consumption of dietary buffer; however, blood HCO3(-) (P < 0.05), Na+, and pCO2 (P < 0.01) increased. Urine pH and urine Na+ concentration increased (P < 0.01) in buffer-treated compared with control animals. Results indicate that sodium bicarbonate can safely be added to the water supply for pigs, with no clinically relevant alterations in acid-base balance because the animals readily compensate for buffer intake.

  3. Physiological response of glandular-haired alfalfa to potato leafhopper (Hemiptera: Cicadellidae) injury.

    PubMed

    Lamp, W O; Alexander, L C; Nguyen, M

    2007-02-01

    Plant tolerance to herbivory is a key approach for managing pests. In alfalfa, Medicago sativa, the potato leafhopper, Empoasca fabae, is a major pest as a result of the cascade of plant responses to piercing-sucking injury. To identify tolerance to its injury based on alfalfa physiology, experiments were conducted in the field and greenhouse. In our comparison of the response of field-grown alfalfa cultivars to standardized leafhopper densities, net photosynthesis and transpiration rates of 'Geneva' leaves were reduced by 18 and 21%, respectively, by leafhopper presence compared with a rate change of <1% of resistant 'EverGreen' leaves. Under greenhouse conditions, alfalfa clones varied in their level of gas exchange (net photosynthesis and transpiration) and stem elongation responses to leafhopper injury. For example, in the comparison of seven clones, net photosynthesis declined an average of 40.7% with leafhopper injury, although individual clones varied from 26.6 to 74.3% reduction. Internode elongation after 2 d was 60.3% less on injured stems compared with healthy stems, but again, the individual clones varied from 17.3 to 91.9%. In a time-course study of selected clones, clones varied in their level of injury just after and 3 d after insect removal. Gas exchange responses of all clones recovered by 7 d after cessation of injury. In a choice test, leafhoppers spent similar amounts of time on the susceptible clone and the most tolerant clone; however, their precise feeding behaviors were not measured. Thus, the variable response of clones to injury may be either true physiological tolerance or antixenosis from a change in feeding behavior. This study showed putative tolerance to leafhopper injury among alfalfa genotypes, suggesting that tolerance could be the basis for crop protection in alfalfa from potato leafhopper injury.

  4. Physiological and transcriptional responses to high temperature in Arthrospira (Spirulina) platensis C1.

    PubMed

    Panyakampol, Jaruta; Cheevadhanarak, Supapon; Sutheeworapong, Sawannee; Chaijaruwanich, Jeerayut; Senachak, Jittisak; Siangdung, Wipawan; Jeamton, Wattana; Tanticharoen, Morakot; Paithoonrangsarid, Kalyanee

    2015-03-01

    Arthrospira (Spirulina) platensis is a well-known commercial cyanobacterium that is used as a food and in feed supplements. In this study, we examined the physiological changes and whole-genome expression in A. platensis C1 exposed to high temperature. We found that photosynthetic activity was significantly decreased after the temperature was shifted from 35°C to 42°C for 2 h. A reduction in biomass production and protein content, concomitant with the accumulation of carbohydrate content, was observed after prolonged exposure to high temperatures for 24 h. Moreover, the results of the expression profiling in response to high temperature at the designated time points (8 h) revealed two distinct phases of the responses. The first was the immediate response phase, in which the transcript levels of genes involved in different mechanisms, including genes for heat shock proteins; genes involved in signal transduction and carbon and nitrogen metabolism; and genes encoding inorganic ion transporters for magnesium, nitrite and nitrate, were either transiently induced or repressed by the high temperature. In the second phase, the long-term response phase, both the induction and repression of the expression of genes with important roles in translation and photosynthesis were observed. Taken together, the results of our physiological and transcriptional studies suggest that dynamic changes in the transcriptional profiles of these thermal-responsive genes might play a role in maintaining cell homeostasis under high temperatures, as reflected in the growth and biochemical composition, particularly the protein and carbohydrate content, of A. platensis C1.

  5. Cognitive, physical and physiological responses of school boy cricketers to a 30-over batting simulation.

    PubMed

    Goble, David; Christie, Candice Jo-Anne

    2016-07-28

    The purpose of this study was to assess how cognitive and physical performance are affected during a prolonged, fatigue-inducing cricket-batting simulation. Fifteen amateur batters from three Eastern Cape schools in South Africa were recruited (mean ± SD: age 17 ± 0.92 years; stature 1.75 ± 0.07 m; body mass 78.3 ± 13.2 kg). Participants completed a 6-stage, 30-over batting simulation (BATEX(©)). During the protocol, there were five periods of cognitive assessment (CogState brief test battery, Melbourne, Australia). The primary outcome measures from each cognitive task were speed and accuracy/error rates. Physiological (heart rate) and physical (sprint times) responses were also recorded. Sprint times deteriorated (d = 0.84; P < 0.01) while physiological responses increased (d = 0.91; P < 0.01) as batting duration increased, with longest times and highest responses occurring in the final stage. Prolonged batting had a large effect on executive task performance (d = 0.85; P = 0.03), and moderate effects on visual attention and vigilance (d = 0.56; P = 0.21) and attention and working memory (d = 0.61; P = 0.11), reducing task performance after 30 overs. Therefore, prolonged batting with repeated shuttle running fatigues amateur batters and adversely affects higher-order cognitive function. This will affect decision-making, response selection, response execution and other batting-related executive processes. We recommend that training should incorporate greater proportions of centre-wicket batting with repeated, high-intensity shuttle running. This will improve batting-related skills and information processing when fatigued, making practice more representative of competition.

  6. Individual differences in behavioral and physiological responsiveness of primiparous dairy cows to machine milking.

    PubMed

    Van Reenen, C G; Van der Werf, J T N; Bruckmaier, R M; Hopster, H; Engel, B; Noordhuizen, J P T M; Blokhuis, H J

    2002-10-01

    An experiment was performed in primiparous dairy cows (n = 23) to examine consistency of individual differences in reactivity to milking, and correlations between measures of behavior, physiology, and milk ejection. Responsiveness to milking was monitored during the first machine milking, on d 2 of lactation, and during milkings on d 4 and 130 of lactation. Measurements included kicking and stepping behavior, plasma cortisol and plasma oxytocin, heart rate, milk yield, milking time, milk flow rate, and residual milk obtained after administration of exogenous oxytocin. With repeated early lactation milkings, residual milk and the incidence of abnormal milk flow curves decreased. On d 130 of lactation all heifers exhibited normal milk ejection. Except for higher plasma cortisol concentrations on d 2, all measures were consistent over time between d 2 and 4 of lactation as indicated by significant rank correlations. Individual differences in the behavioral response to udder preparation were consistent over time between early lactation milkings and d 130 of lactation. Residual milk, milk yield, maximum milk flow rate, plasma oxytocin and heart rate during udder preparation were similarly interrelated on d 2 and 4 of lactation. High heart rate responses on d 2 and 4 were associated with enhanced inhibition of milk ejection. In contrast, behavior recorded during the milking process was unrelated to ease of milk removal. Our results indicate that milking at the beginning of lactation may be stressful to some heifers, to the extent that milk ejection is inhibited, but less disturbing to others. The existence of consistent behavioral and physiological responses in the present study suggests that responsiveness of dairy heifers to milking is mediated by stable animal characteristics.

  7. Divergent Transcriptional Responses to Physiological and Xenobiotic Stress in Giardia duodenalis

    PubMed Central

    McConville, Malcolm J.; Baker, Louise; Korhonen, Pasi K.; Emery, Samantha J.; Svärd, Staffan G.; Gasser, Robin B.; Jex, Aaron R.

    2016-01-01

    Understanding how parasites respond to stress can help to identify essential biological processes. Giardia duodenalis is a parasitic protist that infects the human gastrointestinal tract and causes 200 to 300 million cases of diarrhea annually. Metronidazole, a major antigiardial drug, is thought to cause oxidative damage within the infective trophozoite form. However, treatment efficacy is suboptimal, due partly to metronidazole-resistant infections. To elucidate conserved and stress-specific responses, we calibrated sublethal metronidazole, hydrogen peroxide, and thermal stresses to exert approximately equal pressure on trophozoite growth and compared transcriptional responses after 24 h of exposure. We identified 252 genes that were differentially transcribed in response to all three stressors, including glycolytic and DNA repair enzymes, a mitogen-activated protein (MAP) kinase, high-cysteine membrane proteins, flavin adenine dinucleotide (FAD) synthetase, and histone modification enzymes. Transcriptional responses appeared to diverge according to physiological or xenobiotic stress. Downregulation of the antioxidant system and α-giardins was observed only under metronidazole-induced stress, whereas upregulation of GARP-like transcription factors and their subordinate genes was observed in response to hydrogen peroxide and thermal stressors. Limited evidence was found in support of stress-specific response elements upstream of differentially transcribed genes; however, antisense derepression and differential regulation of RNA interference machinery suggest multiple epigenetic mechanisms of transcriptional control. PMID:27458219

  8. A Review of Cardiac Autonomic Measures: Considerations for Examination of Physiological Response in Children with Autism Spectrum Disorder

    ERIC Educational Resources Information Center

    Benevides, Teal W.; Lane, Shelly J.

    2015-01-01

    The autonomic nervous system (ANS) is responsible for multiple physiological responses, and dysfunction of this system is often hypothesized as contributing to cognitive, affective, and behavioral responses in children. Research suggests that examination of ANS activity may provide insight into behavioral dysregulation in children with autism…

  9. Physiological and behavioral flexibility to an acute CO2 challenge, within and between genotypes in rainbow trout.

    PubMed

    Sadoul, B; Friggens, N C; Valotaire, C; Labbé, L; Colson, V; Prunet, P; Leguen, I

    2017-04-07

    Adaptive capacities, governing the ability of animals to cope with an environmental stressor, have been demonstrated to be strongly dependent upon genetic factors. Two isogenic lines of rainbow trout, previously described for their sensitivity and resilience to an acute confinement challenge, were used in the present study to investigate whether adaptive capacities remain consistent when fish are exposed to a different type of challenge. For this purpose, the effects of a 4-h hypercapnia (CO2 increase) challenge at concentrations relevant in aquaculture conditions are described for the two isogenic lines. Oxygen consumption, cortisol release, group dispersion and group swimming activity were measured before, during and after the challenge. Sensitivity and resilience for each measure were extracted from temporal responses and analyzed using multivariate statistics. The two fish lines displayed significant differences in their cortisol response, translating differences in the stress axis sensitivity to the stressor. On the contrary, both lines showed, for other measures, similar temporal patterns across the study. Notable within line variability in the stress response was observed, despite identical genome between fish. The results are discussed in the context of animal robustness.

  10. Physiological Responses During Multiplay Exergaming in Young Adult Males are Game-Dependent

    PubMed Central

    McGuire, Stephen; Willems, Mark ET

    2015-01-01

    Regular moderate-intensity exercise provides health benefits. The aim of this study was to examine whether the selected exercise intensity and physiological responses during exergaming in a single and multiplayer mode in the same physical space were game-dependent. Ten males (mean ±SD, age: 23 ±5 years, body mass: 84.2 ±15.6 kg, body height: 180 ±7 cm, body mass index: 26.0 ±4.0 kg·m−2) played the games Kinect football, boxing and track & field (3 × ∼10 min, ∼ 2 min rest periods) in similar time sequence in two sessions. Physiological responses were measured with the portable Cosmed K4b2 pulmonary gas exchange system. Single play demands were used to match with a competitive opponent in a multiplay mode. A within-subjects crossover design was used with one-way ANOVA and a post-hoc t-test for analysis (p<0.05). Minute ventilation, oxygen uptake and the heart rate were at least 18% higher during a multiplayer mode for Kinect football and boxing but not for track & field. Energy expenditure was 21% higher during multiplay football. Single play track & field had higher metabolic equivalent than single play football (5.7 ±1.6, range: 3.2–8.6 vs 4.1 ±1.0, range: 3.0–6.1, p<0.05). Exergaming in a multiplayer mode can provide higher physiological demands but the effects are game-dependent. It seems that exergaming with low intensity in a multiplayer mode may provide a greater physical challenge for participants than in a single play mode but may not consistently provide sufficient intensity to acquire health benefits when played regularly as part of a programme to promote and maintain health in young adults. PMID:26240669

  11. Complexity of physiological responses decreases in high-stress musical performance.

    PubMed

    Williamon, Aaron; Aufegger, Lisa; Wasley, David; Looney, David; Mandic, Danilo P

    2013-12-06

    For musicians, performing in front of an audience can cause considerable apprehension; indeed, performance anxiety is felt throughout the profession, with wide ranging symptoms arising irrespective of age, skill level and amount of practice. A key indicator of stress is frequency-specific fluctuations in the dynamics of heart rate known as heart rate variability (HRV). Recent developments in sensor technology have made possible the measurement of physiological parameters reflecting HRV non-invasively and outside of the laboratory, opening research avenues for real-time performer feedback to help improve stress management. However, the study of stress using standard algorithms has led to conflicting and inconsistent results. Here, we present an innovative and rigorous approach which combines: (i) a controlled and repeatable experiment in which the physiological response of an expert musician was evaluated in a low-stress performance and a high-stress recital for an audience of 400 people, (ii) a piece of music with varying physical and cognitive demands, and (iii) dynamic stress level assessment with standard and state-of-the-art HRV analysis algorithms such as those within the domain of complexity science which account for higher order stress signatures. We show that this offers new scope for interpreting the autonomic nervous system response to stress in real-world scenarios, with the evolution of stress levels being consistent with the difficulty of the music being played, superimposed on the stress caused by performing in front of an audience. For an emerging class of algorithms that can analyse HRV independent of absolute data scaling, it is shown that complexity science performs a more accurate assessment of average stress levels, thus providing greater insight into the degree of physiological change experienced by musicians when performing in public.

  12. The physiological consequences of crib-biting in horses in response to an ACTH challenge test.

    PubMed

    Briefer Freymond, S; Bardou, D; Briefer, E F; Bruckmaier, R; Fouché, N; Fleury, J; Maigrot, A-L; Ramseyer, A; Zuberbühler, K; Bachmann, I

    2015-11-01

    Stereotypies are repetitive and relatively invariant patterns of behavior, which are observed in a wide range of species in captivity. Stereotypic behavior occurs when environmental demands produce a physiological response that, if sustained for an extended period, exceeds the natural physiological regulatory capacity of the organism, particularly in situations that include unpredictability and uncontrollability. One hypothesis is that stereotypic behavior functions to cope with stressful environments, but the existing evidence is contradictory. To address the coping hypothesis of stereotypies, we triggered physiological reactions in 22 horses affected by stereotypic behavior (crib-biters) and 21 non-crib-biters (controls), using an ACTH challenge test. Following administration of an ACTH injection, we measured saliva cortisol every 30 min and heart rate (HR) continuously for a period of 3h. We did not find any differences in HR or HR variability between the two groups, but crib-biters (Group CB) had significantly higher cortisol responses than controls (Group C; mean ± SD: CB, 5.84 ± 2.62 ng/ml, C, 4.76 ± 3.04 ng/ml). Moreover, crib-biters that did not perform the stereotypic behavior during the 3-hour test period (Group B) had significantly higher cortisol levels than controls, which was not the case of crib-biters showing stereotypic behavior (Group A) (B, 6.44 ± 2.38 ng/ml A, 5.58 ± 2.69 ng/ml). Our results suggest that crib-biting is a coping strategy that helps stereotypic individuals to reduce cortisol levels caused by stressful situations. We conclude that preventing stereotypic horses from crib-biting could be an inappropriate strategy to control this abnormal behavior, as it prevents individuals from coping with situations that they perceive as stressful.

  13. Physiological and subjective responses to cooling devices on firefighting protective clothing.

    PubMed

    Chou, Chinmei; Tochihara, Yutaka; Kim, Taegyou

    2008-09-01

    The aim of the present study was to examine the effectiveness of ice-packs (ICE) and phase change material (PCM) cooling devices in reducing physiological load based on subjects' physiological and subjective responses while the subjects exercised on a bicycle ergometer while wearing firefighting protective clothing in a relatively high temperature environment (30 degrees C, 50%RH). Subjects were eight graduate students, aged 25.9 years (SD 3.2). Each subject participated in four 50-min exposures: control (CON), ICE, PCM of 5 degrees C [PCM(5)] and 20 degrees C [PCM(20)]. Each subject rested in a pre-test room for 10 min before entering the test-room where they rested for another 10 min, followed by 30 min-exercise and a 10 min-recovery period. The exercise intensity was set at 55%VO(2max). Cooling effects were evaluated by measuring rectal temperature (Tre), mean skin temperature (Tsk), body weight loss and subjective responses. An increase in Tre for PCM(5) and PCM(20) which was less than that for CON and ICE was observed. The increases in Tsk were depressed using cooling devices, but the cooling effects of PCMs were greater than ICE. The subjects with CON felt hotter and wetter than those in the other conditions. The larger surface cooling area, higher melting temperature and softer material of PCMs which reduces absorption capacity caused a decrease in Tre and Tsk for PCM(5) and PCM(20) which was more than that for CON and ICE. Furthermore, PCM(20) does not require refrigeration. These results suggest that PCM(20) is more effective than other cooling devices in reducing the physiological load while wearing firefighting protective clothing.

  14. Physiological Responses During Multiplay Exergaming in Young Adult Males are Game-Dependent.

    PubMed

    McGuire, Stephen; Willems, Mark Et

    2015-06-27

    Regular moderate-intensity exercise provides health benefits. The aim of this study was to examine whether the selected exercise intensity and physiological responses during exergaming in a single and multiplayer mode in the same physical space were game-dependent. Ten males (mean ±SD, age: 23 ±5 years, body mass: 84.2 ±15.6 kg, body height: 180 ±7 cm, body mass index: 26.0 ±4.0 kg·m(-2)) played the games Kinect football, boxing and track & field (3 × ∼10 min, ∼ 2 min rest periods) in similar time sequence in two sessions. Physiological responses were measured with the portable Cosmed K4b(2) pulmonary gas exchange system. Single play demands were used to match with a competitive opponent in a multiplay mode. A within-subjects crossover design was used with one-way ANOVA and a post-hoc t-test for analysis (p<0.05). Minute ventilation, oxygen uptake and the heart rate were at least 18% higher during a multiplayer mode for Kinect football and boxing but not for track & field. Energy expenditure was 21% higher during multiplay football. Single play track & field had higher metabolic equivalent than single play football (5.7 ±1.6, range: 3.2-8.6 vs 4.1 ±1.0, range: 3.0-6.1, p<0.05). Exergaming in a multiplayer mode can provide higher physiological demands but the effects are game-dependent. It seems that exergaming with low intensity in a multiplayer mode may provide a greater physical challenge for participants than in a single play mode but may not consistently provide sufficient intensity to acquire health benefits when played regularly as part of a programme to promote and maintain health in young adults.

  15. Catecholaminergic responses in vas deferens isolated from rats submitted to acute swimming stress.

    PubMed

    Chies, A B; Pereira, O C

    1995-09-01

    The study was performed to examine the responses to catecholamines in vas deferens isolated from rats submitted to acute swimming-induced stress. It was demonstrated that acute stress induces a significant subsensitivity of rat vas deferens to norepinephrine. This subsensitivity was inhibited when the experiment was carried out in the presence of either cocaine (10-5 M) or timolol (10-5 M). On the other hand, the rat vas deferens sensitivity to methoxamine was significantly increased by acute swimming-induced stress. Thus, despite acute swimming stress inducing a reduction in response to norepinephrine, the alpha1-adrenoceptor-mediated contractile response was increased. Additionally there were increases in neuronal uptake and beta2-adrenoceptor activity that opposes the alpha1-adrenoceptor activity. Integrated, these phenomena are responsible for the rat vas deferens subsensitivity to norepinephrine which may be involved in body homeostasis in stressogenic situations.

  16. Using physiology to predict the responses of ants to climatic warming.

    PubMed

    Diamond, Sarah E; Penick, Clint A; Pelini, Shannon L; Ellison, Aaron M; Gotelli, Nicholas J; Sanders, Nathan J; Dunn, Robert R

    2013-12-01

    Physiological intolerance of high temperatures places limits on organismal responses to the temperature increases associated with global climatic change. Because ants are geographically widespread, ecologically diverse, and thermophilic, they are an ideal system for exploring the extent to which physiological tolerance can predict responses to environmental change. Here, we expand on simple models that use thermal tolerance to predict the responses of ants to climatic warming. We investigated the degree to which changes in the abundance of ants under warming reflect reductions in the thermal niche space for their foraging. In an eastern deciduous forest system in the United States with approximately 40 ant species, we found that for some species, the loss of thermal niche space for foraging was related to decreases in abundance with increasing experimental climatic warming. However, many ant species exhibited no loss of thermal niche space. For one well-studied species, Temnothorax curvispinosus, we examined both survival of workers and growth of colonies (a correlate of reproductive output) as functions of temperature in the laboratory, and found that the range of thermal tolerances for colony growth was much narrower than for survival of workers. We evaluated these functions in the context of experimental climatic warming and found that the difference in the responses of these two attributes to temperature generates differences in the means and especially the variances of expected fitness under warming. The expected mean growth of colonies was optimized at intermediate levels of warming (2-4°C above ambient); yet, the expected variance monotonically increased with warming. In contrast, the expected mean and variance of the survival of workers decreased when warming exceeded 4°C above ambient. Together, these results for T. curvispinosus emphasize the importance of measuring reproduction (colony growth) in the context of climatic change: indeed, our examination

  17. Relationships between some psychological assessments, body-build, and physiological stress responses

    PubMed Central

    Bridges, P. K.; Jones, M. T.

    1973-01-01

    A number of physiological responses to the psychological stress of an oral academic examination were observed, including heart rate, respiration rate, blood pressure, urinary 17-oxogenic steroid excretion, and plasma corticosteroid concentration. The results were related to body-build and to four psychological tests: Eysenck Personality Inventory, Taylor Manifest Anxiety Scale, IPAT Anxiety Scale, and Stimulus-Response Inventory. No significant associations were found between the psychological test results and anticipatory physiological activity just before the examination began, including excretion of 17-oxogenic steroids. Respiration rate was not increased by anticipatory stress, unlike the other variables, which were significantly higher than control values taken under resting conditions three months later. The students of primarily linear physique had significantly higher plasma corticosteroid values than the predominantly muscular subjects at the time of the examination, as found previously. They also had significantly higher analogue measures of the degree of anxiety experienced at the examination (assessed both by the subject and by an observer). Therefore, linear subjects appear to experience more anxiety than muscular students in a similar situation of psychological stress. Both the IPAT Scale and S-R Inventory results were significantly higher for the linear group but there were no significant differences for the EPI and TMAS scores, as used in previous studies. The importance of constitutional factors associated with body-build in relation to at least some aspects of personality is strongly suggested by the findings. PMID:4753880

  18. Global transcriptome and physiological responses of Acinetobacter oleivorans DR1 exposed to distinct classes of antibiotics.

    PubMed

    Heo, Aram; Jang, Hyun-Jin; Sung, Jung-Suk; Park, Woojun

    2014-01-01

    The effects of antibiotics on environment-originated nonpathogenic Acinetobacter species have been poorly explored. To understand the antibiotic-resistance mechanisms that function in nonpathogenic Acinetobacter species, we used an RNA-sequencing (RNA-seq) technique to perform global gene-expression profiling of soil-borne Acinetobacter oleivorans DR1 after exposing the bacteria to 4 classes of antibiotics (ampicillin, Amp; kanamycin, Km; tetracycline, Tc; norfloxacin, Nor). Interestingly, the well-known two global regulators, the soxR and the rpoE genes are present among 41 commonly upregulated genes under all 4 antibiotic-treatment conditions. We speculate that these common genes are essential for antibiotic resistance in DR1. Treatment with the 4 antibiotics produced diverse physiological and phenotypic changes. Km treatment induced the most dramatic phenotypic changes. Examination of mutation frequency and DNA-repair capability demonstrated the induction of the SOS response in Acinetobacter especially under Nor treatment. Based on the RNA-seq analysis, the glyoxylate-bypass genes of the citrate cycle were specifically upregulated under Amp treatment. We also identified newly recognized non-coding small RNAs of the DR1 strain, which were also confirmed by Northern blot analysis. These results reveal that treatment with antibiotics of distinct classes differentially affected the gene expression and physiology of DR1 cells. This study expands our understanding of the molecular mechanisms of antibiotic-stress response of environment-originated bacteria and provides a basis for future investigations.

  19. Taste and Physiological Responses to Glucosinolates: Seed Predator versus Seed Disperser

    PubMed Central

    Samuni-Blank, Michal; Izhaki, Ido; Gerchman, Yoram; Dearing, M. Denise; Karasov, William H.; Trabelcy, Beny; Edwards, Thea M.; Arad, Zeev

    2014-01-01

    In contrast to most other plant tissues, fleshy fruits are meant to be eaten in order to facilitate seed dispersal. Although fleshy fruits attract consumers, they may also contain toxic secondary metabolites. However, studies that link the effect of fruit toxins with seed dispersal and predation are scarce. Glucosinolates (GLSs) are a family of bitter-tasting compounds. The fleshy fruit pulp of Ochradenus baccatus was previously found to harbor high concentrations of GLSs, whereas the myrosinase enzyme, which breaks down GLSs to produce foul tasting chemicals, was found only in the seeds. Here we show the differential behavioral and physiological responses of three rodent species to high dose (80%) Ochradenus’ fruits diets. Acomys russatus, a predator of Ochradenus’ seeds, was the least sensitive to the taste of the fruit and the only rodent to exhibit taste-related physiological adaptations to deal with the fruits’ toxins. In contrast, Acomys cahirinus, an Ochradenus seed disperser, was more sensitive to a diet containing the hydrolyzed products of the GLSs. A third rodent (Mus musculus) was deterred from Ochradenus fruits consumption by the GLSs and their hydrolyzed products. We were able to alter M. musculus avoidance of whole fruit consumption by soaking Ochradenus fruits in a water solution containing 1% adenosine monophosphate, which blocks the bitter taste receptor in mice. The observed differential responses of these three rodent species may be due to evolutionary pressures that have enhanced or reduced their sensitivity to the taste of GLSs. PMID:25383693

  20. Growth, metabolism and physiological response of the sea cucumber, Apostichopus japonicus Selenka during periods of inactivity

    NASA Astrophysics Data System (ADS)

    Du, Rongbin; Zang, Yuanqi; Tian, Xiangli; Dong, Shuanglin

    2013-03-01

    The growth, metabolism and physiological response of the sea cucumber, Apostichopus japonicus, were investigated during periods of inactivity. The body weight, oxygen consumption rate (OCR), activities of acidic phosphatase (ACP), alkaline phosphatase (AKP), catalase (CAT) and superoxide dismutase (SOD), and content of heat shock protein 70 (Hsp70) in the body wall and coelomic fluid of A. japonicus were measured during starvation, experimental aestivation and aestivation. The results showed that the body weight of sea cucumber in the three treatments decreased significantly during the experimental period ( P < 0.05). The OCR of sea cucumber reduced in starvation and experimental aestivation treatments, but increased gradually in natural aestivation treatment. The activities of ACP and AKP of sea cucumber decreased gradually in all treatments, whereas those of SOD and CAT as well as Hsp70 content decreased in the starvation and experimental aestivation treatments and increased in natural aestivation treatment. The sea cucumber entered a state of aestivation at 24°C. To some extent, the animals in experimental aestivation were different from those in natural aestivation in metabolism and physiological response. These findings suggested that the aestivation mechanism of A. japonicus is complex and may not be attributed to the elevated temperature only.

  1. Physiological and biochemical responses of resistant and susceptible wheat to injury by Russian wheat aphid.

    PubMed

    Franzen, Lisa D; Gutsche, Andrea R; Heng-Moss, Tiffany M; Higley, Leon G; Sarath, Gautam; Burd, John D

    2007-10-01

    We examined the physiological and biochemical responses of resistant ('Halt' and 'Prairie Red') and susceptible ('TAM 107') wheat, Triticum aestivum L., to injury by the Russian wheat aphid, Diuraphis noxia (Mordvilko). Photosynthetic capacity was evaluated by measuring assimilation/internal CO2 (A/Ci) curves, chlorophyll fluorescence, chlorophyll, and nonstructural carbohydrate content. Total protein and peroxidase specific activity also were determined. No significant differences were detected in chlorophyll concentration between aphid-infested and control TAM 107 plants. The aphid-infested resistant cultivars had similar or significantly higher chlorophyll concentrations compared with their respective control plants. Measurements over time showed that infested Halt plants had delays in photosynthetic senescence, Prairie Red plants had photosynthetic rate changes that were similar to control plants, and TAM 107 plants displayed accelerated photosynthetic senescence patterns. The photochemical and nonphotochemical quenching coefficients were significantly higher in infested Halt plants compared with their respective control plants on day 3. Infested TAM 107 plants had significantly higher photochemical quenching compared with control plants at all times evaluated, and they had significantly higher nonphotochemical quenching on day 3. Throughout the experiment, infested Prairie Red plants exhibited photochemical and nonphotochemical quenching coefficient values that were not significantly different from control plants. Total protein content was not significantly different between aphid-infested and control plants for all cultivars. Differences between physiological responses of infested susceptible and resistant cultivars, particularly temporal changes in photosynthetic activity, imply that resistant Halt and Prairie Red wheat tolerate some impacts of aphid injury on photosynthetic integrity.

  2. Drought stress response in wheat: physiological and molecular analysis of resistant and sensitive genotypes.

    PubMed

    Rampino, Patrizia; Pataleo, Stefano; Gerardi, Carmela; Mita, Giovanni; Perrotta, Carla

    2006-12-01

    Water deficit is a severe environmental stress and the major constraint on plant productivity with an evident effect on plant growth. The aim of this work was to study Triticum and Aegilops seedlings differing in their response to drought stress at the physiological and molecular levels. The identification of resistant and sensitive genotypes was firstly based on the relative water content (RWC) measurement. Further characterization of genotypes contrasting in their response to water stress was performed at the physiological level by determination of RWC, water loss rate (WLR) and free proline content after different hours of dehydration. Modification in the expression level of five dehydrin (DHN) genes was also analysed by reverse transcription-polymerase chain reaction (RT-PCR). Five cDNAs coding for different DHNs were identified and characterized. These genes are not expressed in the well-watered plants, but only in the stressed plants. Four of these cDNAs are related to novel DHN sequences. The results obtained clearly indicate a relation between the expression of these genes and tissue water content. In particular, in the resistant genotypes the expression of DHN genes is initiated even though tissue hydration levels are still high, indicating also in wheat the involvement of these proteins in water retention.

  3. Stimuli responsive deswelling of radiation synthesized collagen hydrogel in simulated physiological environment.

    PubMed

    Zhang, Xiangmei; Xu, Ling; Wei, Shicheng; Zhai, Maolin; Li, Jiuqiang

    2013-08-01

    Collagen hydrogels were prepared via radiation crosslinking. The simulated physiological environmental effects related to their biomedical applications on the volume phase transition of collagen hydrogel were studied, that is stimuli response to ions, temperature, and pH. The deswelling behavior of collagen hydrogel depends on the salt concentration, temperature, pH, and the hydrogel preparation procedure. Meanwhile, hydrogel structure related to the volume phase transition was investigated by FTIR, fluorescence spectrum, and HR-MAS NMR. Deswelling in salt solution caused little change on collagen conformation, and a denser network led to more significant tyrosine-derived fluorescence quenching. Hydrogen bonding between hydrated water and collagen polypeptide chain was dissociated and the activity of hydrophobic side chain increased, inducing a higher extent of contraction with the increasing of salt concentration. Moreover, salt solution treatments weakened the electrostatic interactions, side chains interactions, and hydrogen bonding of collagen hydrogel, which reduced the thermal stability of collagen hydrogel. Comparing with cell-free collagen hydrogel contraction, fibroblasts did not aggravate contraction of collagen hydrogel significantly. This study elucidated the deswelling mechanism of radiation crosslinked collagen hydrogel in simulated physiological environment and provides strategies for controlling the stimuli response of collagen hydrogel in biomedical application.

  4. Growth and physiological responses of maize ( Zea mays L.) to porous silica nanoparticles in soil

    NASA Astrophysics Data System (ADS)

    Suriyaprabha, R.; Karunakaran, G.; Yuvakkumar, R.; Prabu, P.; Rajendran, V.; Kannan, N.

    2012-12-01

    The present study aims to explore the effect of high surface area (360.85 m2 g-1) silica nanoparticles (SNPs) (20-40 nm) extracted from rice husk on the physiological and anatomical changes during maize growth in sandy loam soil at four concentrations (5-20 kg ha-1) in comparison with bulk silica (15-20 kg ha-1). The plant responses to nano and bulk silica treatments were analyzed in terms of growth characteristics, phyto compounds such as total protein, chlorophyll, and other organic compounds (gas chromatography-mass spectroscopy), and silica accumulation (high-resolution scanning electron microscopy). Growth characteristics were much influenced with increasing concentration of SNPs up to 15 kg ha-1 whereas at 20 kg ha-1, no significant increments were noticed. Silica accumulation in leaves was high at 10 and 15 kg ha-1 (0.57 and 0.82 %) concentrations of SNPs. The observed physiological changes show that the expression of organic compounds such as proteins, chlorophyll, and phenols favored to maize treated with nanosilica especially at 15 kg ha-1 compared with bulk silica and control. Nanoscale silica regimes at 15 kg ha-1 has a positive response of maize than bulk silica which help to improve the sustainable farming of maize crop as an alternative source of silica fertilizer.

  5. Analysis of Natural Variation in Bermudagrass (Cynodon dactylon) Reveals Physiological Responses Underlying Drought Tolerance

    PubMed Central

    Cheng, Zhangmin; Ye, Tiantian; Chan, Zhulong

    2012-01-01

    Bermudagrass (Cynodon dactylon) is a widely used warm-season turfgrass and one of the most drought tolerant species. Dissecting the natural variation in drought tolerance and physiological responses will bring us powerful basis and novel insight for plant breeding. In the present study, we evaluated the natural variation of drought tolerance among nine bermudagrass varieties by measuring physiological responses after drought stress treatment through withholding water. Three groups differing in drought tolerance were identified, including two tolerant, five moderately tolerant and two susceptible varieties. Under drought stress condition, drought sensitive variety (Yukon) showed relative higher water loss, more severe cell membrane damage (EL), and more accumulation of hydrogen peroxide (H2O2) and malondialdehyde (MDA), while drought tolerant variety (Tifgreen) exhibited significantly higher antioxidant enzymes activities. Further results indicated that drought induced cell injury in different varieties (Yukon, SR9554 and Tifgreen) exhibited liner correlation with leaf water content (LWC), H2O2 content, MDA content and antioxidant enzyme activities. Additionally, Tifgreen plants had significantly higher levels of osmolytes (proline level and soluble sugars) when compared with Yukon and SR9554 under drought stress condition. Taken together, our results indicated that natural variation of drought stress tolerance in bermudagrass varieties might be largely related to the induced changes of water status, osmolyte accumulation and antioxidant defense system. PMID:23285294

  6. Physiological responses of Brazilian amphibians to an enzootic infection of the chytrid fungus Batrachochytrium dendrobatidis.

    PubMed

    Bovo, Rafael P; Andrade, Denis V; Toledo, Luís Felipe; Longo, Ana V; Rodriguez, David; Haddad, Célio F B; Zamudio, Kelly R; Becker, C Guilherme

    2016-01-13

    Pathophysiological effects of clinical chytridiomycosis in amphibians include disorders of cutaneous osmoregulation and disruption of the ability to rehydrate, which can lead to decreased host fitness or mortality. Less attention has been given to physiological responses of hosts where enzootic infections of Batrachochytrium dendrobatidis (Bd) do not cause apparent population declines in the wild. Here, we experimentally tested whether an enzootic strain of Bd causes significant mortality and alters host water balance (evaporative water loss, EWL; skin resistance, R(s); and water uptake, WU) in individuals of 3 Brazilian amphibian species (Dendropsophus minutus, n = 19; Ischnocnema parva, n = 17; Brachycephalus pitanga, n = 15). Infections with enzootic Bd caused no significant mortality, but we found an increase in R(s) in 1 host species concomitant with a reduction in EWL. These results suggest that enzootic Bd infections can indeed cause sub-lethal effects that could lead to reduction of host fitness in Brazilian frogs and that these effects vary among species. Thus, our findings underscore the need for further assessment of physiological responses to Bd infections in different host species, even in cases of sub-clinical chytridiomycosis and long-term enzootic infections in natural populations.

  7. Effects of Modified Multistage Field Test on Performance and Physiological Responses in Wheelchair Basketball Players

    PubMed Central

    Weissland, Thierry; Faupin, Arnaud; Borel, Benoit; Berthoin, Serge; Leprêtre, Pierre-Marie

    2015-01-01

    A bioenergetical analysis of manoeuvrability and agility performance for wheelchair players is inexistent. It was aimed at comparing the physiological responses and performance obtained from the octagon multistage field test (MFT) and the modified condition in “8 form” (MFT-8). Sixteen trained wheelchair basketball players performed both tests in randomized condition. The levels performed (end-test score), peak values of oxygen uptake (VO2peak), minute ventilation (VEpeak), heart rate (HRpeak), peak and relative blood lactate (Δ[Lact−] = peak – rest values), and the perceived rating exertion (RPE) were measured. MFT-8 induced higher VO2peak and VEpeak values compared to MFT (VO2peak: 2.5 ± 0.6 versus 2.3 ± 0.6 L·min−1 and VEpeak: 96.3 ± 29.1 versus 86.6 ± 23.4 L·min−1; P < 0.05) with no difference in other parameters. Significant relations between VEpeak and end-test score were correlated for both field tests (P < 0.05). At exhaustion, MFT attained incompletely VO2peak and VEpeak. Among experienced wheelchair players, MFT-8 had no effect on test performance but generates higher physiological responses than MFT. It could be explained by demands of wheelchair skills occurring in 8 form during the modified condition. PMID:25802841