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Sample records for altered stress performance

  1. Bisphenol A in oocytes leads to growth suppression and altered stress performance in juvenile rainbow trout.

    Directory of Open Access Journals (Sweden)

    Neelakanteswar Aluru

    Full Text Available BACKGROUND: Bisphenol A (BPA, used in the manufacture of plastics, is ubiquitously distributed in the aquatic environment. However, the effect of maternal transfer of these xenobiotics on embryonic development and growth is poorly understood in fish. We tested the hypothesis that BPA in eggs, mimicking maternal transfer, impact development, growth and stress performance in juveniles of rainbow trout (Oncorhynchus mykiss. METHODOLOGY/PRINCIPAL FINDINGS: Trout oocytes were exposed to 0, 30 and 100 microg.mL(-1 BPA for 3 h in ovarian fluid, followed by fertilization. The embryos were maintained in clean water and sampled temporally over 156-days post-fertilization (dpf, and juveniles were sampled at 400-dpf. The egg BPA levels declined steadily after exposure and were undetectable after 21- dpf. Oocyte exposure to BPA led to a delay in hatching and yolk absorption and a consistently lower body mass over 152-dpf. The growth impairment, especially in the high BPA group, correlated with higher growth hormone (GH content and lower GH receptors gene expression. Also, mRNA abundances of insulin-like growth factors (IGF-1 and IGF-2 and their receptors were suppressed in the BPA treated groups. The juvenile fish grown from the BPA-enriched eggs had lower body mass and showed perturbations in plasma cortisol and glucose response to an acute stressor. CONCLUSION: BPA accumulation in eggs, prior to fertilization, leads to hatching delays, growth suppression and altered stress response in juvenile trout. The somatotropic axis appears to be a key target for BPA impact during early embryogenesis, leading to long term growth and stress performance defects in fish.

  2. Pre-stress performance in an instrumental training predict post-stress behavioral alterations in chronically stressed rats

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    Yoshio eIguchi

    2015-05-01

    Full Text Available Stress is a major factor in the development of major depressive disorder (MDD, but few studies have assessed individual risk based on pre-stress traits. In this study, we employed appetitive instrumental lever pressing with a progressive ratio schedule to assess the individual pre-stress behavioral and cognitive traits in experimentally naïve Sprague–Dawley rats. Based on the behavioral data, the animals were classified into four subgroups (Low Motivation, Quick Learner, Slow Learner, and Hypermotivation, and exposed to chronic unpredictable stress (CUS before monitoring their post-stress responses once each week for 4 weeks to identify early- and late-appearing CUS-induced behavioral phenotypes. The four subgroups exhibited different behavioral phenotypes after CUS. Therefore, we identified distinct relationships between pre-stress traits and the post-stress phenotypes in each subgroup. In addition, many of the CUS-induced phenotypes in rats corresponded to symptoms in human MDD or they had putative relationships with them. We concluded that the consequences of stress may be predicted before stress exposure by determining the pre-stress traits of each individual.

  3. Pre-stress performance in an instrumental training predict post-stress behavioral alterations in chronically stressed rats

    OpenAIRE

    Shigenobu Toda

    2015-01-01

    Stress is a major factor in the development of major depressive disorder (MDD), but few studies have assessed individual risk based on pre-stress traits. In this study, we employed appetitive instrumental lever pressing with a progressive ratio schedule to assess the individual pre-stress behavioral and cognitive traits in experimentally naïve Sprague–Dawley rats. Based on the behavioral data, the animals were classified into four subgroups (Low Motivation, Quick Learner, Slow Learner, and Hy...

  4. Heat stress does not exacerbate tennis-induced alterations in physical performance

    Science.gov (United States)

    Girard, Olivier; Christian, Ryan J; Racinais, Sébastien; Périard, Julien D

    2014-01-01

    Objectives To assess the time course of changes in physical performance in response to match-play tennis under heat stress. Methods Two matches consisting of 20 min of effective playing time (2×10 min segments) were played in COOL (∼102 min; ∼22°C and 70% relative humidity (RH)) and HOT (∼119 min; ∼36°C and 35% RH) environments. Repeated-sprint ability (3×15 m, 15 s rest), 15 m sprint time with a direction change (180°), vertical jump height (squat and countermovement jumps) and leg stiffness (multirebound jumps) were assessed in 12 competitive male players prematch, midmatch and postmatch, and 24 and 48 h after match completion. Results During the repeated-sprint ability test, initial (+2.3% and +3.1%) and cumulated sprint (+1.5% and +2.8%) times increased from prematch to midmatch and postmatch, respectively (p0.05), decreased midmatch and postmatch, respectively, regardless of the condition. Complete recovery in all physical performance markers occurred within 24 h. Conclusions In tennis, match-related fatigue is characterised by impaired repeated-sprint ability, explosive power and leg stiffness at midmatch and postmatch, with values restored to prematch baseline 24 h into recovery. In addition, physical performance responses (match and recovery kinetics) are identical when competing in cool and hot environments. PMID:24668378

  5. Post-fire wood management alters water stress, growth, and performance of pine regeneration in a Mediterranean ecosystem

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    Maranon-Jimenez, Sara; Castro, Jorge; Querejeta, José Ignacio; Fernandez-Ondono, Emilia; Allen, Craig D.

    2013-01-01

    Extensive research has focused on comparing the impacts of post-fire salvage logging versus those of less aggressive management practices on forest regeneration. However, few studies have addressed the effects of different burnt-wood management options on seedling/sapling performance, or the ecophysiological mechanisms underlying differences among treatments. In this study, we experimentally assess the effects of post-fire management of the burnt wood on the growth and performance of naturally regenerating pine seedlings (Pinus pinaster). Three post-fire management treatments varying in degree of intervention were implemented seven months after a high-severity wildfire burned Mediterranean pine forests in the Sierra Nevada, southeast Spain: (a) “No Intervention” (NI, all burnt trees left standing); (b) “Partial Cut plus Lopping” (PCL, felling most of the burnt trees, cutting off branches, and leaving all the biomass on site without mastication); and (c) “Salvage Logging” (SL, felling the burnt trees, piling up the logs and masticating the fine woody debris). Three years after the fire, the growth, foliar nutrient concentrations, and leaf carbon, nitrogen and oxygen isotopic composition (δ13C, δ18O and δ15N) of naturally regenerating seedlings were measured in all the treatments. Pine seedlings showed greatest vigor and size in the PCL treatment, whereas growth was poorest in SL. The nutrient concentrations were similar among treatments, although greater growth in the two treatments with residual wood present indicated higher plant uptake. Seedlings in the SL treatment showed high leaf δ13C and δ18O values indicating severe water stress, in contrast to significantly alleviated water stress indications in the PCL treatment. Seedling growth and physiological performance in NI was intermediate between that of PCL and SL. After six growing seasons, P. pinaster saplings in PCL showed greater growth and cone production than SL saplings. In summary

  6. Stress and work performance

    OpenAIRE

    Pajer, Zdeněk

    2011-01-01

    The thesis focuses on questions of stress and its boundless consequences on individuals and society. The theoretical part helps us to understand and to become familiar with the topic. This part is based on literature review of new studies in the field of stress , studies of coping with stress, on physiological and chemical processes during a stress situation ,on the influence of individuality of certain individual on stress load, on the society and the impact on workers' performance. Subchapt...

  7. Bone alterations by stress in athletes

    International Nuclear Information System (INIS)

    This report describes our experiences with the bone imaging in athletes. We studied 10 athletes and 10 other patients with spondylolisthesis of the lumbar spine and 16 athletes with suspicion of alterations of extremities. An increased uptake of this radiopharmaceutical was detected in six of 10 athletes with spondylolisthesis caused probably by stress fracture. Bone scans were negative in seven of 16 athletes with suspicion of lesion of extremities. In the remaining 9 patients scans were abnormal and showed periosteal injuries, epiphyseal alteration, joint abnormalities, tibial stress fractures and couvert fracture. It was also abnormal in bone injuries not evident in radiography. (orig.)

  8. Stress-related alteration of urine compositions

    NARCIS (Netherlands)

    W. van den Berg; C. Uhlemann; A. Meissner; N. Laube

    2011-01-01

    Increased emotional stress in everyday life influences the way of living and metabolism of people living in developed countries. Contemporaneously, the incidence and prevalence of urolithiasis rises. Does a pathogenetically relevant relationship exist between chronic stress burden and permanently al

  9. Stress and music performance anxiety

    OpenAIRE

    Simoens, Veerle

    2012-01-01

    Acute and chronic stress, as well as accompanying changes of the hypothalamic-pituitary-adrenal (HPA) axis, affect cognitive processes, including memory. In professional musicians occupational stress and music performance anxiety (MPA) are a major source of concern during a musical career, whereas a boost is to a certain extent necessary for a musical performance. ---------- A protocol was successfully designed to induce acute stress in healthy students while measuring electro-encephalography...

  10. Stress and Job Performance

    OpenAIRE

    Mirela-Mihaela Dogaru; Irina Donciu

    2014-01-01

    Solving problems irrational and poor health status of employees, has symptoms of excessive stimulation, boredom and depression has while symptoms of insufficient stimulation. Work analysis is of particular importance both in human resource management and organizational stress management, representing a systematic process for determining the skills, responsibilities and knowledge required for a particular job working in year organization, i.e. the provision of certain activities within organiz...

  11. Repeated swim stress alters brain benzodiazepine receptors measured in vivo

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    Weizman, R.; Weizman, A.; Kook, K.A.; Vocci, F.; Deutsch, S.I.; Paul, S.M.

    1989-06-01

    The effects of repeated swim stress on brain benzodiazepine receptors were examined in the mouse using both an in vivo and in vitro binding method. Specific in vivo binding of (/sup 3/H)Ro15-1788 to benzodiazepine receptors was decreased in the hippocampus, cerebral cortex, hypothalamus, midbrain and striatum after repeated swim stress (7 consecutive days of daily swim stress) when compared to nonstressed mice. In vivo benzodiazepine receptor binding was unaltered after repeated swim stress in the cerebellum and pons medulla. The stress-induced reduction in in vivo benzodiazepine receptor binding did not appear to be due to altered cerebral blood flow or to an alteration in benzodiazepine metabolism or biodistribution because there was no difference in (14C)iodoantipyrine distribution or whole brain concentrations of clonazepam after repeated swim stress. Saturation binding experiments revealed a change in both apparent maximal binding capacity and affinity after repeated swim stress. Moreover, a reduction in clonazepam's anticonvulsant potency was also observed after repeated swim stress (an increase in the ED50 dose for protection against pentylenetetrazol-induced seizures), although there was no difference in pentylenetetrazol-induced seizure threshold between the two groups. In contrast to the results obtained in vivo, no change in benzodiazepine receptor binding kinetics was observed using the in vitro binding method. These data suggest that environmental stress can alter the binding parameters of the benzodiazepine receptor and that the in vivo and in vitro binding methods can yield substantially different results.

  12. Repeated swim stress alters brain benzodiazepine receptors measured in vivo

    International Nuclear Information System (INIS)

    The effects of repeated swim stress on brain benzodiazepine receptors were examined in the mouse using both an in vivo and in vitro binding method. Specific in vivo binding of [3H]Ro15-1788 to benzodiazepine receptors was decreased in the hippocampus, cerebral cortex, hypothalamus, midbrain and striatum after repeated swim stress (7 consecutive days of daily swim stress) when compared to nonstressed mice. In vivo benzodiazepine receptor binding was unaltered after repeated swim stress in the cerebellum and pons medulla. The stress-induced reduction in in vivo benzodiazepine receptor binding did not appear to be due to altered cerebral blood flow or to an alteration in benzodiazepine metabolism or biodistribution because there was no difference in [14C]iodoantipyrine distribution or whole brain concentrations of clonazepam after repeated swim stress. Saturation binding experiments revealed a change in both apparent maximal binding capacity and affinity after repeated swim stress. Moreover, a reduction in clonazepam's anticonvulsant potency was also observed after repeated swim stress [an increase in the ED50 dose for protection against pentylenetetrazol-induced seizures], although there was no difference in pentylenetetrazol-induced seizure threshold between the two groups. In contrast to the results obtained in vivo, no change in benzodiazepine receptor binding kinetics was observed using the in vitro binding method. These data suggest that environmental stress can alter the binding parameters of the benzodiazepine receptor and that the in vivo and in vitro binding methods can yield substantially different results

  13. Combined heat and mental stress alters neurovascular control in humans

    OpenAIRE

    Klein, Jenna C.; Crandall, Craig G.; Matthew Brothers, R.; Carter, Jason R.

    2010-01-01

    This study examined the effect of combined heat and mental stress on neurovascular control. We hypothesized that muscle sympathetic nerve activity (MSNA) and forearm vascular responses to mental stress would be augmented during heat stress. Thirteen subjects performed 5 min of mental stress during normothermia (Tcore; 37 ± 0°C) and heat stress (38 ± 0°C). Heart rate, mean arterial pressure (MAP), MSNA, forearm vascular conductance (FVC; venous occlusion plethysmography), and forearm skin vasc...

  14. Host stress hormones alter vector feeding preferences, success, and productivity.

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    Gervasi, Stephanie S; Burkett-Cadena, Nathan; Burgan, Sarah C; Schrey, Aaron W; Hassan, Hassan K; Unnasch, Thomas R; Martin, Lynn B

    2016-08-17

    Stress hormones might represent a key link between individual-level infection outcome, population-level parasite transmission, and zoonotic disease risk. Although the effects of stress on immunity are well known, stress hormones could also affect host-vector interactions via modification of host behaviours or vector-feeding patterns and subsequent reproductive success. Here, we experimentally manipulated songbird stress hormones and examined subsequent feeding preferences, feeding success, and productivity of mosquito vectors in addition to defensive behaviours of hosts. Despite being more defensive, birds with elevated stress hormone concentrations were approximately twice as likely to be fed on by mosquitoes compared to control birds. Moreover, stress hormones altered the relationship between the timing of laying and clutch size in blood-fed mosquitoes. Our results suggest that host stress could affect the transmission dynamics of vector-borne parasites via multiple pathways. PMID:27512147

  15. REPEATED ACUTE STRESS INDUCED ALTERATIONS IN CARBOHYDRATE METABOLISM IN RAT

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    Nirupama R.

    2010-09-01

    Full Text Available Acute stress induced alterations in the activity levels of rate limiting enzymes and concentration of intermediates of different pathways of carbohydrate metabolism have been studied. Adult male Wistar rats were restrained (RS for 1 h and after an interval of 4 h they were subjected to forced swimming (FS exercise and appropriate controls were maintained. Five rats were killed before the commencement of the experiment (initial controls, 5 control and equal number of stressed rats were killed 2 h after RS and remaining 5 rats in each group were killed 4 h after FS. There was a significant increase in the adrenal 3β- hydroxy steroid dehydrogenase activity following RS, which showed further increase after FS compared to controls and thereby indicated stress response of rats. There was a significant increase in the blood glucose levels following RS which showed further increase and reached hyperglycemic condition after FS. The hyperglycemic condition due to stress was accompanied by significant increases in the activities of glutamate- pyruvate transaminase, glutamate- oxaloacetate transaminase, glucose -6- phosphatase and lactate dehydrogenase and significant decrease in the glucose -6- phosphate dehydrogenase and pyruvate dehydrogenase activities, whereas pyruvate kinase activity did not show any alteration compared to controls. Further, the glycogen and total protein contents of the liver were decreased whereas those of pyruvate and lactate showed significant increase compared to controls after RS as well as FS.The results put together indicate that acute stress induced hyperglycemia results due to increased gluconeogenesis and glycogenolysis without alteration in glycolysis. The study first time reveals that after first acute stress exposure, the subsequent stressful experience augments metabolic stress response leading to hyperglycemia. The results have relevance to human health as human beings are exposed to several stressors in a day and

  16. Oxidative stress-induced proteome alterations target different cellular pathways in human myoblasts

    DEFF Research Database (Denmark)

    Baraibar, Martin A; Hyzewicz, Janek; Rogowska-Wrzesinska, Adelina;

    2011-01-01

    Although increased oxidative stress has been associated with the impairment of proliferation and function of adult human muscle stem cells, proteins either involved in the stress response or damaged by oxidation have not been identified. A parallel proteomics approach was performed for analyzing...... are mainly cytosolic and involved in carbohydrate metabolism, cellular assembly, cellular homeostasis, and protein synthesis and degradation. Pathway analysis revealed skeletal and muscular disorders, cell death, and cancer-related as the main molecular networks altered. Interestingly, these pathways...

  17. Neonatal handling alters maternal emotional response to stress.

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    Reis, Adolfo R; Jacobs, Silvana; Menegotto, Pâmela R; Silveira, Patrícia P; Lucion, Aldo B

    2016-07-01

    Neonatal handling is an experimental procedure used to analyze the effects of environmental interventions during early postpartum days (PPD). Long-lasting effects of repeated stress exposure in the neonatal period on the maternal side are poorly studied in this model. The aim of this study was to verify if handling the pups induces enduring effects on damśstress responses, increasing their risk for depression. Dams were divided into two groups (NH-Non-handled and H-Handled) based on the handling procedure (pups were handled for 1 min/per day from PPD1-PPD10) and then subdivided into four groups (NH, NH + S, H, and H + S) based on the exposure or not to restraint stress after weaning (1 hr/per day for 7 days, PPD22-PPD28). We analyzed damśbehavior in the forced swimming test (FST PPD29-PPD30), plasma basal corticosterone and BDNF levels, as well as adrenal weight (PPD31). The results show that handling alters the stress response of dams to acute and chronic stress, as evidenced by dams of the H group having increased immobility in the first day of FST (p handling may induce a long-lasting effect on maternal stress response; these changes in the damśemotional reactivity increase their susceptibility for the development of psychiatric disorders such as depression. © 2016 Wiley Periodicals, Inc. Dev Psychobiol 58: 614-622, 2016. PMID:27020142

  18. EFFECT OF WORKPLACE STRESS ON JOB PERFORMANCE

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    Azman Ismail

    2015-05-01

    Full Text Available The study examines the relationship between workplace stress and job performance. A survey method was employed to gather self-administered questionnaires from executive and non-executive employees of a leading private investment bank in Peninsular Malaysia. The outcomes of SmartPLS path model analysis of the data showed two important findings: firstly, physiological stress was positively and significantly correlated with job performance. Secondly, psychological stress was positively and significantly correlated with job performance. This finding reveals that physiological and psychological stresses act as important predictors of job performance in the studied organization. The paper provides discussion, implications and conclusion.

  19. Stress-induced altered cholinergic-glutamatergic interactions in the mouse hippocampus.

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    Pavlovsky, Lev; Bitan, Yifat; Shalev, Hadar; Serlin, Yonatan; Friedman, Alon

    2012-09-01

    Psychological stress may lead to long-lasting brain dysfunction, specifically altered emotional and cognitive capabilities. Previous studies have demonstrated persistent changes in the expression of key cholinergic genes in the neocortex and hippocampus following stress with muscarinic receptor-mediated enhanced excitability. In the present study we examined cholinergic-mediated glutamatergic transmission in the hippocampus of mice after exposure to stress and its potential role in synaptic plasticity and altered behavior. Adult male mice were tested one month after repeated forced swimming test. Non-treated age-matched animals served as controls. Electrophysiological recordings were performed in the acute in-vitro slice preparation. CA1 pyramidal neurons were recorded using whole cell patch configuration. Extracellular recordings were done in response to Shaffer collaterals (SC) or stratum orien (SO) stimulation. Animal behavior in response to inhibition of acetylcholinesterase (AChE) was tested in open field paradigms. In whole cell patch recordings the frequency of excitatory post-synaptic currents (EPSCs) was significantly increased in response to muscarinic activation in stress-exposed animals. This enhanced cholinergic-modulated excitatory transmission is associated with facilitation of long-term potentiation (LTP) in response to tetanic stimulation at the SO but not at the SC. Stress-related behavioral modulation via central cholinergic pathways was enhanced by the central AChE inhibitor, physostigmine, thus further supporting the notion that stress is associated with long lasting hypersensitivity to acetylcholine. Our results revealed a pathway-specific enhancement of cholinergic-dependent glutamatergic transmission in the hippocampus after stress. These changes may underlie specific hippocampal malfunction, including cognitive and emotional disturbances, as observed in patients with post-traumatic stress disorder (PTSD). PMID:22796599

  20. Restraint Stress Impairs Glucose Homeostasis Through Altered Insulin Signalling in Sprague-Dawley Rat.

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    Morakinyo, Ayodele O; Ajiboye, Kolawole I; Oludare, Gabriel O; Samuel, Titilola A

    2016-01-01

    The study investigated the potential alteration in the level of insulin and adiponectin, as well as the expression of insulin receptors (INSR) and glucose transporter 4 GLUT-4 in chronic restraint stress rats. Sprague-Dawley rats were randomly divided into two groups: the control group and stress group in which the rats were exposed to one of the four different restraint stressors; 1 h, twice daily for a period of 7 days (S7D), 14 days (S14D) and 28 days (S28D). Glucose tolerance and insulin sensitivity were evaluated following the final stress exposure. ELISA were performed to assess the level of insulin and adiponectin as well as expression of INSR and GLUT4 protein in skeletal muscle. Plasma corticosterone level was also determined as a marker of stress exposure. Restraint stress for 7 days caused transient glucose intolerance, while S14D rats demonstrated increased glucose intolerance and insulin insensitivity. However, restraint stress for 28 days had no effect on glucose tolerance, but did cause an increase in glucose response to insulin challenge. The serum level of adiponectin was significantly (pcontrol value while insulin remained unchanged except at in S28D rats that had a significant (pcontrol counterparts. Restraint stress caused glucose intolerance and insulin insensitivity in male Sprague-Dawley rats, which becomes accommodated with prolonged exposure and was likely related to the blunted insulin signalling in skeletal muscle. PMID:27574760

  1. EFFECT OF WORKPLACE STRESS ON JOB PERFORMANCE

    OpenAIRE

    Azman Ismail; Noorshafine Saudin; Yusof Ismail; Ainon Jauhariah Abu Samah; Rizal Abu Bakar; Norish Norsiah Aminudin

    2015-01-01

    The study examines the relationship between workplace stress and job performance. A survey method was employed to gather self-administered questionnaires from executive and non-executive employees of a leading private investment bank in Peninsular Malaysia. The outcomes of SmartPLS path model analysis of the data showed two important findings: firstly, physiological stress was positively and significantly correlated with job performance. Secondly, psychological stress was positively and signi...

  2. Stress, stress-induced cortisol responses, and eyewitness identification performance.

    Science.gov (United States)

    Sauerland, Melanie; Raymaekers, Linsey H C; Otgaar, Henry; Memon, Amina; Waltjen, Thijs T; Nivo, Maud; Slegers, Chiel; Broers, Nick J; Smeets, Tom

    2016-07-01

    In the eyewitness identification literature, stress and arousal at the time of encoding are considered to adversely influence identification performance. This assumption is in contrast with findings from the neurobiology field of learning and memory, showing that stress and stress hormones are critically involved in forming enduring memories. This discrepancy may be related to methodological differences between the two fields of research, such as the tendency for immediate testing or the use of very short (1-2 hours) retention intervals in eyewitness research, while neurobiology studies insert at least 24 hours. Other differences refer to the extent to which stress-responsive systems (i.e., the hypothalamic-pituitary-adrenal axis) are stimulated effectively under laboratory conditions. The aim of the current study was to conduct an experiment that accounts for the contemporary state of knowledge in both fields. In all, 123 participants witnessed a live staged theft while being exposed to a laboratory stressor that reliably elicits autonomic and glucocorticoid stress responses or while performing a control task. Salivary cortisol levels were measured to control for the effectiveness of the stress induction. One week later, participants attempted to identify the thief from target-present and target-absent line-ups. According to regression and receiver operating characteristic analyses, stress did not have robust detrimental effects on identification performance. Copyright © 2016 John Wiley & Sons, Ltd. © 2016 The Authors Behavioral Sciences & the Law Published by John Wiley & Sons Ltd. PMID:27417874

  3. Performance-Based Rewards and Work Stress

    Science.gov (United States)

    Ganster, Daniel C.; Kiersch, Christa E.; Marsh, Rachel E.; Bowen, Angela

    2011-01-01

    Even though reward systems play a central role in the management of organizations, their impact on stress and the well-being of workers is not well understood. We review the literature linking performance-based reward systems to various indicators of employee stress and well-being. Well-controlled experiments in field settings suggest that certain…

  4. Stress for Success: How to Optimize Your Performance.

    Science.gov (United States)

    Gmelch, Walter H.

    1983-01-01

    This article explores linkages between stress and effective job performance: while too much stress can lead to burnout, too little stressful stimulation can result in boredom. Generating the proper amount of stress for optimal job performance is discussed. (PP)

  5. Nutrient loading alters the performance of key nutrient exchange mutualisms.

    Science.gov (United States)

    Shantz, Andrew A; Lemoine, Nathan P; Burkepile, Deron E

    2016-01-01

    Nutrient exchange mutualisms between phototrophs and heterotrophs, such as plants and mycorrhizal fungi or symbiotic algae and corals, underpin the functioning of many ecosystems. These relationships structure communities, promote biodiversity and help maintain food security. Nutrient loading may destabilise these mutualisms by altering the costs and benefits each partner incurs from interacting. Using meta-analyses, we show a near ubiquitous decoupling in mutualism performance across terrestrial and marine environments in which phototrophs benefit from enrichment at the expense of their heterotrophic partners. Importantly, heterotroph identity, their dependence on phototroph-derived C and the type of nutrient enrichment (e.g. nitrogen vs. phosphorus) mediated the responses of different mutualisms to enrichment. Nutrient-driven changes in mutualism performance may alter community organisation and ecosystem processes and increase costs of food production. Consequently, the decoupling of nutrient exchange mutualisms via alterations of the world's nitrogen and phosphorus cycles may represent an emerging threat of global change. PMID:26549314

  6. [Sleep, stress, neurogenesis and driving performance].

    Science.gov (United States)

    Garbarino, S

    2012-01-01

    The enormous number of traffic accidents, implying a firm place in the top three death-rate causation in most industrialised countries, has inspired the development of studies of its major cause, i.e. human behaviour. Many traffic accidents are caused by, or at least related to, inadequate mental workload and, when it is either too low (vigilance, sleepiness) or too high (stress). Poor or inadequate sleep is a frequent result of being "stressed out." Professional and commuter drivers suffering from both daytime sleepiness and stress, two main factors impairment road safety mediated by behaviours including cognitive lapses, errors, and intentional traffic violations. Previous research has shown the association between stress or excessive daytime sleepiness and crash involvement but they never considered their linkage and their similar brain action: the hippocampus, amygdala, and prefrontal cortex undergo stress or poor or inadequate sleep induced structural remodelling (neuroplasticity and neurogenensis), which alters behavioral and physiological responses which can be either adaptive or damaging. PMID:23213813

  7. Stress, performance, and control room operations

    International Nuclear Information System (INIS)

    The notion of control room operator performance being detrimentally affected by stress has long been the focus of considerable conjecture. It is important to gain a better understanding of the validity of this concern for the development of effective severe-accident management approaches. This paper illustrates the undeniable negative impact of stress on a wide variety of tasks. A computer-controlled simulated work environment was designed in which both male and female operators were closely monitored during the course of the study for both stress level (using the excretion of the urine catecholamines epinephrine and norepinephrine as an index) and job performance. The experimental parameters employed by the study when coupled with the subsequent statistical analyses of the results allow one to make some rather striking comments with respect to how a given operator might respond to a situation that he or she perceives to be psychologically stressful (whether the stress be externally or internally generated). The findings of this study clearly indicated that stress does impact operator performance on tasks similar in nature to those conducted by control room operators and hence should be seriously considered in the development of severe-accident management strategies

  8. A history of stress alters drought calcium signalling pathways in Arabidopsis.

    Science.gov (United States)

    Knight, H; Brandt, S; Knight, M R

    1998-12-01

    Environmental stresses commonly encountered by plants lead to rapid transient elevations in cytosolic free calcium concentration ([Ca2+]cyt) (Bush, 1995; Knight et al., 1991). These cellular calcium (Ca2+) signals lead ultimately to the increased expression of stress-responsive genes, including those encoding proteins of protective function (Knight et al., 1996; Knight et al., 1997). The kinetics and magnitude of the Ca2+ signal, or 'calcium signature', differ between different stimuli and are thought to contribute to the specificity of the end response (Dolmetsch et al., 1997; McAinsh and Hetherington, 1998). We measured [Ca2+]cyt changes during treatment with mannitol (to mimic drought stress) in whole intact seedlings of Arabidopsis thaliana. The responses of plants which were previously exposed to osmotic and oxidative stresses were compared to those of control plants. We show here that osmotic stress-induced Ca2+ responses can be markedly altered by previous encounters with either osmotic or oxidative stress. The nature of the alterations in Ca2+ response depends on the identity and severity of the previous stress: oxidative stress pre-treatment reduced the mannitol-induced [Ca2+]cyt response whereas osmotic stress pretreatment increased the [Ca2+]cyt response. Therefore, our data show that different combinations of environmental stress can produce novel Ca2+ signal outputs. These alterations are accompanied by corresponding changes in the patterns of osmotic stress-induced gene expression and, in the case of osmotic stress pre-treatment, the acquisition of stress-tolerance. This suggests that altered Ca2+ responses encode a 'memory' of previous stress encounters and thus may perhaps be involved in acclimation to environmental stresses. PMID:10069075

  9. Keratins Are Altered in Intestinal Disease-Related Stress Responses.

    Science.gov (United States)

    Helenius, Terhi O; Antman, Cecilia A; Asghar, Muhammad Nadeem; Nyström, Joel H; Toivola, Diana M

    2016-01-01

    Keratin (K) intermediate filaments can be divided into type I/type II proteins, which form obligate heteropolymers. Epithelial cells express type I-type II keratin pairs, and K7, K8 (type II) and K18, K19 and K20 (type I) are the primary keratins found in the single-layered intestinal epithelium. Keratins are upregulated during stress in liver, pancreas, lung, kidney and skin, however, little is known about their dynamics in the intestinal stress response. Here, keratin mRNA, protein and phosphorylation levels were studied in response to murine colonic stresses modeling human conditions, and in colorectal cancer HT29 cells. Dextran sulphate sodium (DSS)-colitis was used as a model for intestinal inflammatory stress, which elicited a strong upregulation and widened crypt distribution of K7 and K20. K8 levels were slightly downregulated in acute DSS, while stress-responsive K8 serine-74 phosphorylation (K8 pS74) was increased. By eliminating colonic microflora using antibiotics, K8 pS74 in proliferating cells was significantly increased, together with an upregulation of K8 and K19. In the aging mouse colon, most colonic keratins were upregulated. In vitro, K8, K19 and K8 pS74 levels were increased in response to lipopolysaccharide (LPS)-induced inflammation in HT29 cells. In conclusion, intestinal keratins are differentially and dynamically upregulated and post-translationally modified during stress and recovery. PMID:27626448

  10. Improved Growth and Stress Tolerance in the Arabidopsis oxt1 Mutant Triggered by Altered Adenine Metabolism

    Institute of Scientific and Technical Information of China (English)

    Suchada Sukrong; Kil-Young Yun; Patrizia Stadler; Charan Kumar; Tony Facciuolo; Barbara A.Moffatt; Deane L.Falcone

    2012-01-01

    Plants perceive and respond to environmental stresses with complex mechanisms that are often associated with the activation of antioxidant defenses.A genetic screen aimed at isolating oxidative stress-tolerant lines of Arabidopsis thaliana has identified oxt1,a line that exhibits improved tolerance to oxidative stress and elevated temperature but displays no apparent deleterious growth effects under non-stress conditions.Oxt1 harbors a mutation that arises from the altered expression of a gene encoding adenine phosphoribosyltransferase (APT1),an enzyme that converts adenine to adenosine monophosphate (AMP),indicating a link between purine metabolism,whole-plant growth responses,and stress acclimation.The oxt1 mutation results in decreased APT1 expression that leads to reduced enzymatic activity.Correspondingly,oxt1 plants possess elevated levels of adenine.Decreased APT enzyme activity directly correlates with stress resistance in transgenic lines that ectopically express APT1.The metabolic alteration in oxt1 plants also alters the expression of several antioxidant defense genes and the response of these genes to oxidative challenge.Finally,it is shown that manipulation of adenine levels can induce stress tolerance to wild-type plants.Collectively,these results show that alterations in cellular adenine levels can trigger stress tolerance and improve growth,leading to increases in plant biomass.The results also suggest that adenine might play a part in the signals that modulate responses to abiotic stress and plant growth.

  11. Cerebrovascular expression of proteins related to inflammation, oxidative stress and neurotoxicity is altered with aging

    Directory of Open Access Journals (Sweden)

    Luo Jinhua

    2010-10-01

    Full Text Available Abstract Background Most neurodegenerative diseases are age-related disorders; however, how aging predisposes the brain to disease has not been adequately addressed. The objective of this study is to determine whether expression of proteins in the cerebromicrovasculature related to inflammation, oxidative stress and neurotoxicity is altered with aging. Methods Brain microvessels are isolated from Fischer 344 rats at 6, 12, 18 and 24 months of age. Levels of interleukin (IL-1β and IL-6 RNA are determined by RT-PCR and release of cytokines into the media by ELISA. Vessel conditioned media are also screened by ELISA for IL-1α, monocyte chemoattractant protein-1 (MCP-1, tumor necrosis factor-α, (TNFα, and interferon γ (IFNγ. Immunofluorescent analysis of brain sections for IL-1β and IL-6 is performed. Results Expression of IL-1β and IL-6, both at RNA and protein levels, significantly (p Conclusions These data demonstrate that cerebrovascular expression of proteins related to inflammation, oxidative stress and neurotoxicity is altered with aging and suggest that the microvasculature may contribute to functional changes in the aging brain.

  12. A measure of stress for athletic performance.

    Science.gov (United States)

    Seggar, J F; Pedersen, D M; Hawkes, N R; McGown, C

    1997-02-01

    The Athlete Stress Inventory of 49 items was developed. Using factor analysis on the intercorrelations of responses of 148 women student-athletes, four orthogonal factors of stress in athletes were identified-Negative Mood, Team Compatibility, Physical Well-being, and Academic Efficacy. Scales for these factors were reliable and valid. The predictive validity of these scores was investigated by correlations with the athletic performance of 32 women athletes on three intercollegiate teams-tennis, gymnastics, and basketball. Stress scores (except Emotional Mood) reported four days prior to competition tended to be significantly correlated with performance for the individual sports (tennis and gymnastics) but not for the group sport (basket-ball). The correlation involving Physical Well-being was not significant for gymnasts. PMID:9132713

  13. Can Architectural Design alter the Physiological reaction to Psychosocial Stress ?

    DEFF Research Database (Denmark)

    Brorson Fich, Lars; Jönsson, Peter; Kirkegaard, Poul Henning;

    2014-01-01

    Is has long been established, that views to natural scenes can a have a dampening effect on physiological stress responses. However, as people in Europe, Canada and North America today spent 50-85% of their time indoors, attention might also be paid to how the artificial man-made indoor environme...

  14. Altered NO3- assimilation in P-stressed plants

    International Nuclear Information System (INIS)

    To examine P stress effects on NO3- uptake and assimilation, young tobacco plants were deprived of external P for 12 days and at selected times exposed to 15NO3- for 12h uptake periods. In -P plants, tissue P concentrations and growth decreased progressively with time relative to controls. Uptake of 15NO3- per g root DW was restricted markedly, being 70% of the control rate on the day 3 and only 17% on day 9. Additional disruptions in the NO3- assimilation pathway were evident, as larger proportions of absorbed 15NO3- were retained in the root and soluble reduced-15N accumulated in leaves with increasing P stress. The results indicate that transport processes controlling NO3- uptake into the root symplasm and its release into the xylem are major points of regulations in plants responding to P deficiency

  15. Dual-task performance under acute stress in female adolescents with borderline personality disorder.

    Science.gov (United States)

    Kaess, Michael; Parzer, Peter; Koenig, Julian; Resch, Franz; Brunner, Romuald

    2016-09-01

    Research to elucidate early alterations of higher cognitive processes in adolescents with BPD is rare. This study investigated differences in dual-task performance in adolescents with BPD during stress and non-stress conditions. The study sample comprised 30 female adolescents with BPD and 34 healthy controls. The impact of stress on dual-task performance was measured using a standardized stressor. Self-reports of distress and measures of heart rate (HR) were obtained to measure stress reactivity. There were no group differences in task performance. Under stress conditions, the performance on the auditory task decreased in both groups but without significant group differences. Healthy controls showed an increase of mean HR after stress induction compared to no change in the BPD group. The finding of attenuated HR response to acute stress in adolescent patients with BPD may contradict current theories that the affective hyperresponsivity in BPD is based on a biologically determined mechanism. PMID:26852226

  16. Global metabolomic responses of Nitrosomonas europaea 19718 to cold stress and altered ammonia feeding patterns

    KAUST Repository

    Lu, Huijie

    2015-11-05

    © 2015 Springer-Verlag Berlin Heidelberg The model ammonia-oxidizing bacterium Nitrosomonas europaea represents one of the environmentally and biotechnologically significant microorganisms. Genome-based studies over the last decade have led to many intriguing discoveries about its cellular biochemistry and physiology. However, knowledge regarding the regulation of overall metabolic routes in response to various environmental stresses is limited due to a lack of comprehensive, time-resolved metabolomic analyses. In this study, gas chromatography–mass spectrometry (GC-MS)-based metabolic profiling was performed to characterize the temporal variations of N. europaea 19718 intercellular metabolites in response to varied temperature (23 and 10 °C) and ammonia feeding patterns (shock loading and continuous feeding of 20 mg N/L). Approximately 87 metabolites were successfully identified and mapped to the existing pathways of N. europaea 19718, allowing interpretation of the influence of temperature and feeding pattern on metabolite levels. In general, varied temperature had a more profound influence on the overall metabolism than varied feeding patterns. Total extracellular metabolite concentrations (relative to internal standards and normalized to biomass weight) were lower under cold stress and shock loading conditions compared with the control (continuous feeding at 23 °C). Cold stress caused the widespread downregulation of metabolites involved in central carbon metabolism, amino acid, and lipid synthesis (e.g., malonic acid, succinic acid, putrescine, and phosphonolpyruvate). Metabolites that showed differences under varied feeding patterns were mainly involved in nucleotide acid, amino acid, and lipid metabolism (e.g., adenine, uracil, and spermidine). This study highlighted the roles of central carbon and nitrogen metabolism in countering cold stress and altered ammonia availability. In addition, transcriptomic, proteomic, and metabolomic data from three

  17. Oxidative stress can alter the antigenicity of immunodominant peptides

    DEFF Research Database (Denmark)

    Weiskopf, Daniela; Schwanninger, Angelika; Weinberger, Birgit; Almanzar, Giovanni; Parson, Walther; Buus, Søren; Lindner, Herbert; Grubeck-Loebenstein, Beatrix

    2010-01-01

    APCs operate frequently under oxidative stress induced by aging, tissue damage, pathogens, or inflammatory responses. Phagocytic cells produce peroxides and free-radical species that facilitate pathogen clearance and can in the case of APCs, also lead to oxidative modifications of antigenic...... proteins and peptides. Little information is available presently about the consequences of such modifications on the immune response. To model oxidative modification of an immunodominant antigenic peptide, we oxidized the methionine residue of the human CMV pp65(495-503) (NLVPMVATV) peptide. Such...... modifications of an antigenic peptide can affect MHC binding or TCR recognition. Using binding and dissociation assays, we demonstrate that oxidative modification of the CMVpp65(495-503) peptide leads to a decreased binding of the pMHC complex to the TCR, whereas binding of the peptide to the MHC class I...

  18. Stress habituation and alterations in perceived stress predict BMI percentile changes across a school year

    Science.gov (United States)

    Adolescents experience stressful situations at a high rate during school. Indeed, school is the most common source of stress for teens. This high rate of stress may promote increases in adiposity during a developmental period important for establishing the adult physique. Adiposity gains may be th...

  19. Altered oscillatory brain dynamics after repeated traumatic stress

    Directory of Open Access Journals (Sweden)

    Ruf Martina

    2007-10-01

    Full Text Available Abstract Background Repeated traumatic experiences, e.g. torture and war, lead to functional and structural cerebral changes, which should be detectable in cortical dynamics. Abnormal slow waves produced within circumscribed brain regions during a resting state have been associated with lesioned neural circuitry in neurological disorders and more recently also in mental illness. Methods Using magnetoencephalographic (MEG-based source imaging, we mapped abnormal distributions of generators of slow waves in 97 survivors of torture and war with posttraumatic stress disorder (PTSD in comparison to 97 controls. Results PTSD patients showed elevated production of focally generated slow waves (1–4 Hz, particularly in left temporal brain regions, with peak activities in the region of the insula. Furthermore, differential slow wave activity in right frontal areas was found in PTSD patients compared to controls. Conclusion The insula, as a site of multimodal convergence, could play a key role in understanding the pathophysiology of PTSD, possibly accounting for what has been called posttraumatic alexithymia, i.e., reduced ability to identify, express and regulate emotional responses to reminders of traumatic events. Differences in activity in right frontal areas may indicate a dysfunctional PFC, which may lead to diminished extinction of conditioned fear and reduced inhibition of the amygdala.

  20. Cell proliferation alterations in Chlorella cells under stress conditions

    International Nuclear Information System (INIS)

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  1. Cell proliferation alterations in Chlorella cells under stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rioboo, Carmen [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); O' Connor, Jose Enrique [Laboratorio de Citomica, Unidad Mixta de Investigacion CIPF-UVEG, Centro de Investigacion Principe Felipe, Avda. Autopista del Saler, 16, 46013 Valencia (Spain); Prado, Raquel; Herrero, Concepcion [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); Cid, Angeles, E-mail: cid@udc.es [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain)

    2009-09-14

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  2. Corticotropin-releasing factor receptors and stress-related alterations of gut motor function.

    OpenAIRE

    Taché, Yvette; Bonaz, Bruno

    2007-01-01

    Over the past few decades, corticotropin-releasing factor (CRF) signaling pathways have been shown to be the main coordinators of the endocrine, behavioral, and immune responses to stress. Emerging evidence also links the activation of CRF receptors type 1 and type 2 with stress-related alterations of gut motor function. Here, we review the role of CRF receptors in both the brain and the gut as part of key mechanisms through which various stressors impact propulsive activity of the gastrointe...

  3. Stress during Adolescence Alters Palatable Food Consumption in a Context-Dependent Manner

    OpenAIRE

    Handy, Christine; Yanaga, Stephanie; Reiss, Avery; Zona, Nicole; Robinson, Emily; Saxton, Katherine B.

    2016-01-01

    Food consumption and preferences may be shaped by exposure to stressful environments during sensitive periods in development, and even small changes in consumption can have important effects on long term health. Adolescence is increasingly recognized as a sensitive period, in which adverse experiences can alter development, but the specific programming effects that may occur during adolescence remain incompletely understood. The current study seeks to explore the effects of stress during late...

  4. Juvenile stress enhances anxiety and alters corticosteroid receptor expression in adulthood

    OpenAIRE

    Brydges, Nichola M.; Jin, Rowen; Seckl, Jonathan,; Holmes, Megan C; Drake, Amanda J.; Hall, Jeremy

    2013-01-01

    BackgroundExposure to stress in early life is correlated with the development of anxiety disorders in adulthood. The underlying mechanisms are not fully understood, but an imbalance in corticosteroid receptor (CR) expression in the limbic system, particularly the hippocampus, has been implicated in the etiology of anxiety disorders. However, little is known about how prepubertal stress in the so called “juvenile” period might alter the expression of these receptors.AimsTherefore, the aim of t...

  5. A Dopamine Receptor D2-Type Agonist Attenuates the Ability of Stress to Alter Sleep in Mice

    OpenAIRE

    Jefferson, F.; Ehlen, J. C.; Williams, N S; Montemarano, J. J.; Paul, K. N.

    2014-01-01

    Although sleep disruptions that accompany stress reduce quality of life and deteriorate health, the mechanisms through which stress alters sleep remain obscure. Psychological stress can alter sleep in a variety of ways, but it has been shown to be particularly influential on rapid eye movement (REM) sleep. Prolactin (PRL), a sexually dimorphic, stress-sensitive hormone whose basal levels are higher in females, has somnogenic effects on REM sleep. In the current study, we examined the relation...

  6. Enhanced Negative Emotion and Alcohol Craving, and Altered Physiological Responses Following Stress and Cue Exposure in Alcohol Dependent Individuals

    OpenAIRE

    Sinha, Rajita; Fox, Helen C.; Hong, Kwangik A.; Bergquist, Keri; Bhagwagar, Zubin; Siedlarz, Kristen M.

    2008-01-01

    Chronic alcohol abuse is associated with changes in stress and reward pathways that could alter vulnerability to emotional stress and alcohol craving. This study examines whether chronic alcohol abuse is associated with altered stress and alcohol craving responses. Treatment-engaged, 28-day abstinent alcohol-dependent individuals (ADs; 6F/22M), and social drinkers (SDs; 10F/18M) were exposed to a brief guided imagery of a personalized stressful, alcohol-related and neutral-relaxing situation,...

  7. Stress-induced alterations in large-scale functional networks of the rodent brain.

    Science.gov (United States)

    Henckens, Marloes J A G; van der Marel, Kajo; van der Toorn, Annette; Pillai, Anup G; Fernández, Guillén; Dijkhuizen, Rick M; Joëls, Marian

    2015-01-15

    Stress-related psychopathology is associated with altered functioning of large-scale brain networks. Animal research into chronic stress, one of the most prominent environmental risk factors for development of psychopathology, has revealed molecular and cellular mechanisms potentially contributing to human mental disease. However, so far, these studies have not addressed the system-level changes in extended brain networks, thought to critically contribute to mental disorders. We here tested the effects of chronic stress exposure (10 days immobilization) on the structural integrity and functional connectivity patterns in the brain, using high-resolution structural MRI, diffusion kurtosis imaging, and resting-state functional MRI, while confirming the expected changes in neuronal dendritic morphology using Golgi-staining. Stress effectiveness was confirmed by a significantly lower body weight and increased adrenal weight. In line with previous research, stressed animals displayed neuronal dendritic hypertrophy in the amygdala and hypotrophy in the hippocampal and medial prefrontal cortex. Using independent component analysis of resting-state fMRI data, we identified ten functional connectivity networks in the rodent brain. Chronic stress appeared to increase connectivity within the somatosensory, visual, and default mode networks. Moreover, chronic stress exposure was associated with an increased volume and diffusivity of the lateral ventricles, whereas no other volumetric changes were observed. This study shows that chronic stress exposure in rodents induces alterations in functional network connectivity strength which partly resemble those observed in stress-related psychopathology. Moreover, these functional consequences of stress seem to be more prominent than the effects on gross volumetric change, indicating their significance for future research. PMID:25462693

  8. Nursing students’ perceived stress and influences in clinical performance

    OpenAIRE

    Laila Akhu-Zaheya; Insaf Shaban; Wejdan Khater

    2015-01-01

    Background: It is known that stress related to clinical training among nursing students could contribute to many physical and mental problems. However, little empirical evidence about the influence of stress in nurse students’ clinical performance Objective: The objective of this study was to assess the association between perceived stresses, stress related factors, and students’ clinical performance. Method: Using the perceived stress scale, 539 Jordanian nursing students from 2 publ...

  9. Cytosine methylation alteration in natural populations of Leymus chinensis induced by multiple abiotic stresses.

    Directory of Open Access Journals (Sweden)

    Yingjie Yu

    Full Text Available BACKGROUND: Human activity has a profound effect on the global environment and caused frequent occurrence of climatic fluctuations. To survive, plants need to adapt to the changing environmental conditions through altering their morphological and physiological traits. One known mechanism for phenotypic innovation to be achieved is environment-induced rapid yet inheritable epigenetic changes. Therefore, the use of molecular techniques to address the epigenetic mechanisms underpinning stress adaptation in plants is an important and challenging topic in biological research. In this study, we investigated the impact of warming, nitrogen (N addition, and warming+nitrogen (N addition stresses on the cytosine methylation status of Leymus chinensis Tzvel. at the population level by using the amplified fragment length polymorphism (AFLP, methylation-sensitive amplified polymorphism (MSAP and retrotransposon based sequence-specific amplification polymorphism (SSAP techniques. METHODOLOGY/PRINCIPAL FINDINGS: Our results showed that, although the percentages of cytosine methylation changes in SSAP are significantly higher than those in MSAP, all the treatment groups showed similar alteration patterns of hypermethylation and hypomethylation. It meant that the abiotic stresses have induced the alterations in cytosine methylation patterns, and the levels of cytosine methylation changes around the transposable element are higher than the other genomic regions. In addition, the identification and analysis of differentially methylated loci (DML indicated that the abiotic stresses have also caused targeted methylation changes at specific loci and these DML might have contributed to the capability of plants in adaptation to the abiotic stresses. CONCLUSIONS/SIGNIFICANCE: Our results demonstrated that abiotic stresses related to global warming and nitrogen deposition readily evoke alterations of cytosine methylation, and which may provide a molecular basis for rapid

  10. Interaction of Metabolic Stress with Chronic Mild Stress in Altering Brain Cytokines and Sucrose Preference

    OpenAIRE

    Remus, Jennifer L.; Stewart, Luke T.; Camp, Robert M.; Novak, Colleen M.; Johnson, John D.

    2015-01-01

    There is growing evidence that metabolic stressors increase an organism’s risk of depression. Chronic mild stress is a popular animal model of depression and several serendipitous findings have suggested that food deprivation prior to sucrose testing in this model is necessary to observe anhedonic behaviors. Here, we directly tested this hypothesis by exposing animals to chronic mild stress and used an overnight two bottle sucrose test (food ad libitum) on day 5 and 10, then food and water de...

  11. Stress in Junior Medical Students: Relationship to Personality and Performance.

    Science.gov (United States)

    Linn, Bernard S.; Zeppa, Robert

    1984-01-01

    A study of student stress before and after a clinical clerkship examined the relationship of favorable or unfavorable stress, as perceived by the student, to locus of control and self-esteem. The major finding was an association of unfavorable stress with poor academic performance. Stress management training is recommended. (MSE)

  12. Stress intensity and performance capabilities of law enforcement officers

    Directory of Open Access Journals (Sweden)

    Nikolaeva N.V.

    2014-09-01

    Full Text Available We discuss the problem of the stress influence on the performance of law enforcement officers. The importance of the stress connection with psychological and psychophysical functioning is caused by the fact that many professional tasks solving is possible only in case of effective adaptation to the difficult conditions of work. The concepts such as stress and performance, as well as the mechanisms of biological adaptation to stress and the effects of stress on the individual police officer, are considered. Attention is paid to the differences between male and female stress and causes of stress in occupations with a large amount of communication activity. We conducted an empirical study in which we investigated the relationship of stress severity and the performance of law enforcement officers, as well as the differences in law enforcement employees performance depending on stress presence, its level, and gender.

  13. Rifaximin Alters Intestinal Bacteria and Prevents Stress-Induced Gut Inflammation and Visceral Hyperalgesia in Rats

    Science.gov (United States)

    Xu, Dabo; Gao, Jun; Gillilland, Merritt; Wu, Xiaoyin; Song, Il; Kao, John Y.; Owyang, Chung

    2014-01-01

    Background & Aims Rifaximin is used to treat patients with functional gastrointestinal disorders, but little is known about its therapeutic mechanism. We propose that rifaximin modulates the ileal bacterial community, reduces subclinical inflammation of the intestinal mucosa, and improves gut barrier function to reduce visceral hypersensitivity. Methods We induced visceral hyperalgesia in rats, via chronic water avoidance or repeat restraint stressors, and investigated whether rifaximin altered the gut microbiota, prevented intestinal inflammation, and improved gut barrier function. Quantitative polymerase chain reaction and 454 pyrosequencing were used to analyze bacterial 16S rRNA in ileal contents from the rats. Reverse transcription, immunoblot, and histologic analyses were used to evaluate levels of cytokines, the tight junction protein occludin, and mucosal inflammation, respectively. Intestinal permeability and rectal sensitivity were measured. Results Water avoidance and repeat restraint stress each led to visceral hyperalgesia, accompanied by mucosal inflammation and impaired mucosal barrier function. Oral rifaximin altered the composition of bacterial communities in the ileum (Lactobacillus species became the most abundant) and prevented mucosal inflammation, impairment to intestinal barrier function, and visceral hyperalgesia in response to chronic stress. Neomycin also changed the composition of the ileal bacterial community (Proteobacteria became the most abundant species). Neomycin did not prevent intestinal inflammation or induction of visceral hyperalgesia induced by water avoidance stress. Conclusions Rifaximin alters the bacterial population in the ileum of rats, leading to a relative abundance of Lactobacillus. These changes prevent intestinal abnormalities and visceral hyperalgesia in response to chronic psychological stress. PMID:24161699

  14. Effect of Hemin on Brain Alterations and Neuroglobin Expression in Water Immersion Restraint Stressed Rats

    Directory of Open Access Journals (Sweden)

    Merhan Ragy

    2016-01-01

    Full Text Available In the brain, the heme oxygenase (HO system has been reported to be very active and its modulation seems to play a crucial role in the pathophysiology of neurodegenerative disorders. Hemin as HO-1 inducer has been shown to attenuate neuronal injury so the goal of this study was to assess the effect of hemin therapy on the acute stress and how it would modulate neurological outcome. Thirty male albino rats were divided into three groups: control group and stressed group with six-hour water immersion restraint stress (WIRS and stressed group, treated with hemin, in which each rat received a single intraperitoneal injection of hemin at a dose level of 50 mg/kg body weight at 12 hours before exposure to WIRS. Stress hormones, oxidative stress markers, malondialdehyde (MDA, and total antioxidant capacity (TAC were measured and expressions of neuroglobin and S100B mRNA in brain tissue were assayed. Our results revealed that hemin significantly affects brain alterations induced by acute stress and this may be through increased expression of neuroglobin and through antioxidant effect. Hemin decreased blood-brain barrier damage as it significantly decreased the expression of S100B. These results suggest that hemin may be an effective therapy for being neuroprotective against acute stress.

  15. Mindfulness meditation training alters stress-related amygdala resting state functional connectivity: a randomized controlled trial.

    Science.gov (United States)

    Taren, Adrienne A; Gianaros, Peter J; Greco, Carol M; Lindsay, Emily K; Fairgrieve, April; Brown, Kirk Warren; Rosen, Rhonda K; Ferris, Jennifer L; Julson, Erica; Marsland, Anna L; Bursley, James K; Ramsburg, Jared; Creswell, J David

    2015-12-01

    Recent studies indicate that mindfulness meditation training interventions reduce stress and improve stress-related health outcomes, but the neural pathways for these effects are unknown. The present research evaluates whether mindfulness meditation training alters resting state functional connectivity (rsFC) of the amygdala, a region known to coordinate stress processing and physiological stress responses. We show in an initial discovery study that higher perceived stress over the past month is associated with greater bilateral amygdala-subgenual anterior cingulate cortex (sgACC) rsFC in a sample of community adults (n = 130). A follow-up, single-blind randomized controlled trial shows that a 3-day intensive mindfulness meditation training intervention (relative to a well-matched 3-day relaxation training intervention without a mindfulness component) reduced right amygdala-sgACC rsFC in a sample of stressed unemployed community adults (n = 35). Although stress may increase amygdala-sgACC rsFC, brief training in mindfulness meditation could reverse these effects. This work provides an initial indication that mindfulness meditation training promotes functional neuroplastic changes, suggesting an amygdala-sgACC pathway for stress reduction effects. PMID:26048176

  16. Expectancy of Stress-Reducing Aromatherapy Effect and Performance on a Stress-Sensitive Cognitive Task

    OpenAIRE

    Irina Chamine; Oken, Barry S.

    2015-01-01

    Objective. Stress-reducing therapies help maintain cognitive performance during stress. Aromatherapy is popular for stress reduction, but its effectiveness and mechanism are unclear. This study examined stress-reducing effects of aromatherapy on cognitive function using the go/no-go (GNG) task performance and event related potentials (ERP) components sensitive to stress. The study also assessed the importance of expectancy in aromatherapy actions. Methods. 81 adults were randomized to 3 aroma...

  17. Altered stress patterns and increased risk for postpartum depression among low-income pregnant women.

    Science.gov (United States)

    Scheyer, Kathryn; Urizar, Guido G

    2016-04-01

    Postpartum depression (PPD) has been associated with a number of negative maternal and infant health outcomes. Despite these adverse health effects, few studies have prospectively examined patterns of pre- and postnatal stress that may increase a woman's risk for PPD. The current study examined whether the timing of altered salivary cortisol patterns and perceived stress levels during pregnancy and at 3 months postpartum was associated with PPD symptoms among 100 low-income mothers. Higher levels of PPD were found among women with a lower cortisol awakening response (first and second trimester), lower average daily cortisol (second trimester), a flatter diurnal cortisol pattern (second and third trimester and at 3 months postpartum), and a less abrupt drop in both cortisol and perceived stress from the third trimester to 3 months postpartum. These results support the need for early screening and regulation of stress levels to promote depression prevention efforts in at-risk populations. PMID:26275372

  18. Fatty acid ethanolamide levels are altered in borderline personality and complex posttraumatic stress disorders.

    Science.gov (United States)

    Schaefer, Carola; Enning, Frank; Mueller, Juliane K; Bumb, J Malte; Rohleder, Cathrin; Odorfer, Thorsten M; Klosterkötter, Joachim; Hellmich, Martin; Koethe, Dagmar; Schmahl, Christian; Bohus, Martin; Leweke, F Markus

    2014-08-01

    Borderline personality (BPD) and complex posttraumatic stress disorders (PTSD) are both powerfully associated with the experience of interpersonal violence during childhood and adolescence. The disorders frequently co-occur and often result in pervasive problems in, e.g., emotion regulation and altered pain perception, where the endocannabinoid system is deeply involved. We hypothesize an endocannabinoid role in both disorders. We investigated serum levels of the endocannabinoids anandamide and 2-arachidonoylglycerol and related fatty acid ethanolamides (FAEs) in BPD, PTSD, and controls. Significant alterations were found for both endocannabinoids in BPD and for the FAE oleoylethanolamide in PTSD suggesting a respective link to both disorders. PMID:24253425

  19. Alteration of methotrexate binding to human serum albumin induced by oxidative stress. Spectroscopic comparative study

    Science.gov (United States)

    Maciążek-Jurczyk, M.; Sułkowska, A.; Równicka-Zubik, J.

    2016-01-01

    Changes of oxidative modified albumin conformation by comparison of non-modified (HSA) and modified (oHSA) human serum albumin absorption spectra, Red Edge Excitation Shift (REES) effect and fluorescence synchronous spectra were investigated. Studies of absorption spectra indicated that changes in the value of absorbance associated with spectral changes in the region from 200 to 250 nm involve structural alterations related to variations in peptide backbone conformation. Analysis of the REES effect allowed for the observation of changes caused by oxidation in the region of the hydrophobic pocket containing the tryptophanyl residue. Synchronous fluorescence spectroscopy confirmed changes of the position of the tryptophanyl and tyrosil residues fluorescent band. Effect of oxidative stress on binding of methotrexate (MTX) was investigated by spectrofluorescence, UV-VIS and 1HNMR spectroscopy. MTX caused the fluorescence quenching of non-modified (HSA) and modified (oHSA) human serum albumin molecule. The values of binding constants, Hill's coefficients and a number of binding sites in the protein molecule in the high affinity binding site were calculated for the binary MTX-HSA and MTX-oHSA systems. For these systems, qualitative analysis in the low affinity binding sites was performed with the use of the 1HNMR technique.

  20. Effect of Perceived Stress on Student Performance in Dental School.

    Science.gov (United States)

    Sanders, Anne E.; Lushington, Kurt

    2002-01-01

    Examined the relationship between perceived stress and academic performance in 202 dental students at an Australian dental school. Found little support for an association between increased factor stress scores on the Dental Environmental Stress (DES) questionnaire and reduced academic performance. (EV)

  1. Prenatal stress is a vulnerability factor for altered morphology and biological activity of microglia cells.

    Directory of Open Access Journals (Sweden)

    Joanna eŚlusarczyk

    2015-03-01

    Full Text Available Several lines of evidence suggest that the dysregulation of the immune system is an important factor in the development of depression. Microglia are the resident macrophages of the central nervous system and a key player in innate immunity of the brain. We hypothesized that prenatal stress (an animal model of depression as a priming factor could affect microglial cells and might lead to depressive-like disturbances in adult male rat offspring. We investigated the behavioral changes (sucrose preference test, Porsolt test, the expression of C1q and CD40 mRNA and the level of microglia (Iba1 positive in 3 month old control and prenatally stressed male offspring rats. In addition, we characterized the morphological and biochemical parameters of potentially harmful (NO, iNOS, IL-1β, IL-18, IL-6, TNF-α, CCL2, CXCL12, CCR2, CXCR4 and beneficial (IGF-1, BDNF phenotypes in cultures of microglia obtained from the cortices of 1-2 days old control and prenatally stressed pups. The adult prenatally stressed rats showed behavioral (anhedonic- and depression-like disturbances, enhanced expression of microglial activation markers and an increased number of Iba1-immunopositive cells in the hippocampus and frontal cortex. The morphology of glia was altered in cultures from prenatally stressed rats, as demonstrated by immunofluorescence microscopy. Moreover, in these cultures, we observed enhanced expression of CD40 and MHC II and release of pro-inflammatory cytokines, including IL-1β, IL-18, TNF-α and IL-6. Prenatal stress significantly up-regulated levels of the chemokines CCL2, CXCL12 and altered expression of their receptors, CCR2 and CXCR4 while IGF-1 production was suppressed in cultures of microglia from prenatally stressed rats.Our results suggest that prenatal stress may lead to excessive microglia activation and contribute to the behavioral changes observed in depression in adulthood.

  2. Prenatal stress is a vulnerability factor for altered morphology and biological activity of microglia cells.

    Science.gov (United States)

    Ślusarczyk, Joanna; Trojan, Ewa; Głombik, Katarzyna; Budziszewska, Bogusława; Kubera, Marta; Lasoń, Władysław; Popiołek-Barczyk, Katarzyna; Mika, Joanna; Wędzony, Krzysztof; Basta-Kaim, Agnieszka

    2015-01-01

    Several lines of evidence suggest that the dysregulation of the immune system is an important factor in the development of depression. Microglia are the resident macrophages of the central nervous system and a key player in innate immunity of the brain. We hypothesized that prenatal stress (an animal model of depression) as a priming factor could affect microglial cells and might lead to depressive-like disturbances in adult male rat offspring. We investigated the behavioral changes (sucrose preference test, Porsolt test), the expression of C1q and CD40 mRNA and the level of microglia (Iba1 positive) in 3-month-old control and prenatally stressed male offspring rats. In addition, we characterized the morphological and biochemical parameters of potentially harmful (NO, iNOS, IL-1β, IL-18, IL-6, TNF-α, CCL2, CXCL12, CCR2, CXCR4) and beneficial (insulin-like growth factor-1 (IGF-1), brain derived neurotrophic factor (BDNF)) phenotypes in cultures of microglia obtained from the cortices of 1-2 days old control and prenatally stressed pups. The adult prenatally stressed rats showed behavioral (anhedonic- and depression-like) disturbances, enhanced expression of microglial activation markers and an increased number of Iba1-immunopositive cells in the hippocampus and frontal cortex. The morphology of glia was altered in cultures from prenatally stressed rats, as demonstrated by immunofluorescence microscopy. Moreover, in these cultures, we observed enhanced expression of CD40 and MHC II and release of pro-inflammatory cytokines, including IL-1β, IL-18, TNF-α and IL-6. Prenatal stress significantly up-regulated levels of the chemokines CCL2, CXCL12 and altered expression of their receptors, CCR2 and CXCR4 while IGF-1 production was suppressed in cultures of microglia from prenatally stressed rats. Our results suggest that prenatal stress may lead to excessive microglia activation and contribute to the behavioral changes observed in depression in adulthood. PMID

  3. The biopsychosocial model of stress in adolescence: self-awareness of performance versus stress reactivity

    OpenAIRE

    Rith-Najarian, Leslie R.; McLaughlin, Katie A.; Sheridan, Margaret A.; Nock, Matthew K.

    2014-01-01

    Extensive research among adults supports the biopsychosocial (BPS) model of challenge and threat, which describes relationships among stress appraisals, physiological stress reactivity, and performance; however, no previous studies have examined these relationships in adolescents. Perceptions of stressors as well as physiological reactivity to stress increase during adolescence, highlighting the importance of understanding the relationships among stress appraisals, physiological reactivity, a...

  4. Alterations of CNS structure & function by charged particle radiation & resultant oxidative stress

    Science.gov (United States)

    Nelson, Gregory; Chang, Polly; Favre, Cecile; Fike, John; Komarova, Natalia; Limoli, Charles; Mao, Xiao-Wen; Obenaus, Andre; Raber, Jacob; Spigelman, Igor; Soltesz, Ivan; Song, Sheng-Kwei; Stampanoni, Marco; Vlkolinsky, Roman; Wodarz, Dominik

    were complex and suggested continuous remodeling of the brain for up to 6 months. Thus we demonstrated a suite of CNS structural and functional changes after proton and iron ion exposure in the low dose regime. Based on these findings we will now test whether oxidative stress mediates the reactions of CNS to radiation exposure and what role radiation quality and dose rate play in the responses. We will use cultured neural precursor cells (mouse human) to detect changes in oxidative status and differentiation as functions of charged particle charge and velocity. These results will inform the selection of particles for many in vivo measurements that will compare wild type mice to a transgenic strain that over-expresses a human catalase gene (which inactivates hydrogen peroxide) in the mitochondrial compartment. This will explicitly test the role of reactive oxygen species in mediating the mechanisms underlying the CNS endpoints that we will measure. We will extend the electrophysiological measurements on individual nerves in hippocampal slices to characterize both inhibitory and excitatory synapses. Further, multi-electrode arrays will be used to follow correlated electrical activity in different hippocampal regions in order to understand network-level function as well as synaptic efficacy and plasticity. Controlled oxidative stress on irradiated samples will explore whether response mechanisms are shared. To link alterations in neurogenesis to performance we will explore behavioral changes mediated by the hippocampus simultaneously with measures of expression of the Arc gene in newly-born neurons. This will test whether decrements in performance correlate with loss of new cells and whether behavior properly stimulates functional integration of the new cells; the behavioral paradigm will be contextual fear conditioning. We will develop mathematical frameworks for CNS responses to radiation in order to inform risk estimates. Finally, we will couple a high

  5. Time Course of Behavioral Alteration and mRNA Levels of Neurotrophic Factor Following Stress Exposure in Mouse.

    Science.gov (United States)

    Hashikawa, Naoya; Ogawa, Takumi; Sakamoto, Yusuke; Ogawa, Mami; Matsuo, Yumi; Zamami, Yoshito; Hashikawa-Hobara, Narumi

    2015-08-01

    Stress is known to affect neurotrophic factor expression, which induces depression-like behavior. However, whether there are time-dependent changes in neurotrophic factor mRNA expression following stress remains unclear. In the present study, we tested whether chronic stress exposure induces long-term changes in depression-related behavior, serum corticosterone, and hippocampal proliferation as well as neurotrophic factor family mRNA levels, such as brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3), and ciliary neurotrophic factor (CNTF), in the mouse hippocampus. The mRNA level of neurotrophic factors (BDNF, NGF, NT-3, and CNTF) was measured using the real-time PCR. The serum corticosterone level was evaluated by enzyme-linked immunosorbent assay, and, for each subject, the hippocampal proliferation was examined by 5-bromo-2-deoxyuridine immunostaining. Mice exhibited depression-like behavior in the forced-swim test (FST) and decreased BDNF mRNA and hippocampal proliferation in the middle of the stress exposure. After 15 days of stress exposure, we observed increased immobility in the FST, serum corticosterone levels, and BDNF mRNA levels and degenerated hippocampal proliferation, maintained for at least 2 weeks. Anhedonia-like behavior in the sucrose preference test and NGF mRNA levels were decreased following 15 days of stress. NGF mRNA levels were significantly higher 1 week after stress exposure. The current data demonstrate that chronic stress exposure induces prolonged BDNF and NGF mRNA changes and increases corticosterone levels and depression-like behavior in the FST, but does not alter other neurotrophic factors or performance in the sucrose preference test. PMID:25820756

  6. Protective effect of Labisia pumila on stress-induced behavioral, biochemical, and immunological alterations.

    Science.gov (United States)

    Kour, Kiranjeet; Sharma, Neelam; Chandan, Bal Krishan; Koul, Surrinder; Sangwan, Payare Lal; Bani, Sarang

    2010-10-01

    The aim of the present study was to investigate the antistress potential of LABISIA PUMILA aqueous extract (LPPM/A003) using a battery of tests widely employed in different stressful situations. Pretreatment of experimental animals with LPPM/A003 caused an increase in the swimming endurance and hypoxia time and also showed the recovery of physical stress-induced depletion of neuromuscular coordination and scopolamine induced memory deficit. LPPM/A003 at graded doses reversed the chronic restraint stress (RST), induced depletion of CD4 (+) and CD8 (+) T lymphocytes, NK cell population, and corresponding cytokines expression besides downregulating the stress-induced increase in plasma corticosterone, a major stress hormone. In addition, LPPM/A003 reversed the chronic stress-induced increase in adrenal gland weight, serum alanine aminotransferase (ALT), alkaline phosphatase (ALP), and hepatic lipid peroxidation (LP) levels and augmented the RST induced decrease in hepatic glutathione (GSH), thymus and spleen weight. Thus, we conclude that LPPM/A003 has the ability to reverse the alterations produced by various stressful stimuli and therefore restores homeostasis. PMID:20217640

  7. Altered Gene Expression, Mitochondrial Damage and Oxidative Stress: Converging Routes in Motor Neuron Degeneration

    Directory of Open Access Journals (Sweden)

    Luisa Rossi

    2012-01-01

    Full Text Available Motor neuron diseases (MNDs are a rather heterogeneous group of diseases, with either sporadic or genetic origin or both, all characterized by the progressive degeneration of motor neurons. At the cellular level, MNDs share features such as protein misfolding and aggregation, mitochondrial damage and energy deficit, and excitotoxicity and calcium mishandling. This is particularly well demonstrated in ALS, where both sporadic and familial forms share the same symptoms and pathological phenotype, with a prominent role for mitochondrial damage and resulting oxidative stress. Based on recent data, however, altered control of gene expression seems to be a most relevant, and previously overlooked, player in MNDs. Here we discuss which may be the links that make pathways apparently as different as altered gene expression, mitochondrial damage, and oxidative stress converge to generate a similar motoneuron-toxic phenotype.

  8. No alterations in diurnal cortisol profiles before and during the treatment in patients with stress-related exhaustion

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    Anna Sjörs

    2015-02-01

    Full Text Available Introduction Several theories have emerged in recent years suggesting that neuroendocrinological alterations, mainly changes in cortisol, could be of importance with respect to the link between chronic stress and disease. This study investigated possible deviations in the diurnal cortisol profiles of patients with clinically diagnosed stress-related exhaustion (exhaustion disorder – ED compared with healthy controls. Material and methods Salivary cortisol samples taken at home in the morning directly after waking up, 30 min later, and in the evening were compared between ED patients (N = 122; 25% men and healthy controls (N = 98; 44% men. Follow-up measurements were performed after 6 months (79 patients and 12 months (68 patients of the treatment. Results There were no clear differences in diurnal salivary cortisol profiles between the patients and healthy controls. Moreover, salivary cortisol levels and diurnal profiles did not change significantly during the treatment in the patient group. There was some indication of a smaller cortisol awakening response in the male patients compared to the male controls, but the difference appeared to be mainly related to the antidepressant use. Conclusions Diurnal salivary cortisol profiles, at least as measured in this study, give a rather poor reflection of the prolonged stress exposure experienced by patients with ED. Such basal salivary cortisol measurements do not seem suitable as biomarkers for stress-related conditions such as ED or burnout, or as an aid to assess the effects of prolonged stress load in a routine clinical practice.

  9. An Investigation of the Combined Effect of Stress, Fatigue and Workload on Human Performance: Position Paper

    Science.gov (United States)

    Mock, Jessica

    2005-01-01

    Stress, fatigue, and workload affect worker performance. NSF reported that 61% of respondents state losing concentration at work while 79% occasionally or frequently made errors as a result of being fatigued. Shift work, altered work schedules, long hours of continuous wakefulness, and sleep loss can create sleep and circadian disruptions that degrade waking fundions causing stress and fatigue. Review of the literature has proven void of information that links the combined effects of fatigue, stress, and workload to human performance. This paper will address which occupational factors within stress, fatigue, and workload were identified as occupational contributors to performance changes. The results of this research will be apglied to underlying models and algorithms that will help predict performance changes in control room operators.

  10. Heat acclimation alters the sleep and behavior based thermoregulatory dynamics of rats in heat stress

    Directory of Open Access Journals (Sweden)

    Sinha RK

    2013-12-01

    Full Text Available Background: It is well understood that the high environmental heat significantly affects the brain physiology of mammals, particularly the sleep and behavior of the subjects. The objective of the present work is to quantify the effects of acclimatization to the high environmental heat on sleep and behavioral activities in heat stress conditions. Methods: The polygraphic data involved simultaneous recordings of cortical electroencephalogram (EEG, electrooculogram (EOG, and electromyogram (EMG were recorded both on chart as well as in digital format to study the sleep-wake parameters in three different age groups of freely moving rats following exposure to high environmental heat. Each age group was subdivided into four groups: the acute heat stress group, subjected to a single exposure of 4h at 38°C in the biological oxygen demand (BOD incubator; the chronic heat stress group, exposed for 21 days, for 1 h each day, at 38°C in the BOD; acute heat stress followed by 21 days of chronic heat acclimatization and the handling control group. Open field and elevated plus-maze behavior was also analyzed following different exposure setup of high environmental heat. Results: The analyses of results suggest that acclimatization to the high environmental heat significantly alters the effects of acute exposure of high environmental heat on different sleep-wake as well as behavioral parameters. Conclusion: Acclimatization to environmental heat shifts the thermoregulatory set-point and thus these altered changes in sleep and behavior have been observed. Paste Full conclusion here

  11. Prolonged endoplasmic reticulum stress alters placental morphology and causes low birth weight

    International Nuclear Information System (INIS)

    The role of endoplasmic reticulum (ER) stress in pregnancy remains largely unknown. Pregnant mice were subcutaneously administered tunicamycin (Tun), an ER stressor, as a single dose [0, 50, and 100 μg Tun/kg/body weight (BW)] on gestation days (GDs) 8.5, 12.5, and 15.5. A high incidence (75%) of preterm delivery was observed only in the group treated with Tun 100 μg/kg BW at GD 15.5, indicating that pregnant mice during late gestation are more susceptible to ER stress on preterm delivery. We further examined whether prolonged in utero exposure to ER stress affects fetal development. Pregnant mice were subcutaneously administered a dose of 0, 20, 40, and 60 μg Tun/kg from GD 12.5 to 16.5. Tun treatment decreased the placental and fetal weights in a dose-dependent manner. Histological evaluation showed the formation of a cluster of spongiotrophoblast cells in the labyrinth zone of the placenta of Tun-treated mice. The glycogen content of the fetal liver and placenta from Tun-treated mice was lower than that from control mice. Tun treatment decreased mRNA expression of Slc2a1/glucose transporter 1 (GLUT1), which is a major transporter for glucose, but increased placental mRNA levels of Slc2a3/GLUT3. Moreover, maternal exposure to Tun resulted in a decrease in vascular endothelial growth factor receptor-1 (VEGFR-1), VEGFR-2, and placental growth factor. These results suggest that excessive and exogenous ER stress may induce functional abnormalities in the placenta, at least in part, with altered GLUT and vascular-related gene expression, resulting in low infant birth weight. - Highlights: • Maternal exposure to excessive ER stress induced preterm birth and IUGR. • Prolonged excessive ER stress altered the formation of the placental labyrinth. • ER stress decreased GLUT1 mRNA expression in the placenta, but increased GLUT3. • ER stress-induced IUGR causes decreased glycogen and altered glucose transport

  12. Prolonged endoplasmic reticulum stress alters placental morphology and causes low birth weight

    Energy Technology Data Exchange (ETDEWEB)

    Kawakami, Takashige, E-mail: tkawakami@ph.bunri-u.ac.jp; Yoshimi, Masaki; Kadota, Yoshito; Inoue, Masahisa; Sato, Masao; Suzuki, Shinya

    2014-03-01

    The role of endoplasmic reticulum (ER) stress in pregnancy remains largely unknown. Pregnant mice were subcutaneously administered tunicamycin (Tun), an ER stressor, as a single dose [0, 50, and 100 μg Tun/kg/body weight (BW)] on gestation days (GDs) 8.5, 12.5, and 15.5. A high incidence (75%) of preterm delivery was observed only in the group treated with Tun 100 μg/kg BW at GD 15.5, indicating that pregnant mice during late gestation are more susceptible to ER stress on preterm delivery. We further examined whether prolonged in utero exposure to ER stress affects fetal development. Pregnant mice were subcutaneously administered a dose of 0, 20, 40, and 60 μg Tun/kg from GD 12.5 to 16.5. Tun treatment decreased the placental and fetal weights in a dose-dependent manner. Histological evaluation showed the formation of a cluster of spongiotrophoblast cells in the labyrinth zone of the placenta of Tun-treated mice. The glycogen content of the fetal liver and placenta from Tun-treated mice was lower than that from control mice. Tun treatment decreased mRNA expression of Slc2a1/glucose transporter 1 (GLUT1), which is a major transporter for glucose, but increased placental mRNA levels of Slc2a3/GLUT3. Moreover, maternal exposure to Tun resulted in a decrease in vascular endothelial growth factor receptor-1 (VEGFR-1), VEGFR-2, and placental growth factor. These results suggest that excessive and exogenous ER stress may induce functional abnormalities in the placenta, at least in part, with altered GLUT and vascular-related gene expression, resulting in low infant birth weight. - Highlights: • Maternal exposure to excessive ER stress induced preterm birth and IUGR. • Prolonged excessive ER stress altered the formation of the placental labyrinth. • ER stress decreased GLUT1 mRNA expression in the placenta, but increased GLUT3. • ER stress-induced IUGR causes decreased glycogen and altered glucose transport.

  13. SaliCylic Acid-Altering Arabidopsis Mutants Response to Cd Stress

    Institute of Scientific and Technical Information of China (English)

    Lu; Tian; Liang; Wu

    2012-01-01

    To evaluate the role of endogenous SA in plant response to Cd stress,Arabidopsis wild type(Columbia)and its SA-altering mutants snc1 (suppressor of npr1-1, constitutive) with high SA level, nahG(tansgenic line)with low SA level and npr1-1(non-expressor of PR gene)with SA signaling blockage were used in this study. Results showed that a greater growth inhibition occurred in snc1,while a less inhibition was observed in nahG and npr1-1 plants. Although the anti-oxidative enzymes SOD and POD increased upon Cd exposure,they were insufficient to remove oxidative stress,especially in snc1 plants. The accumulations of soluble sugar and proline in the tested plants were positively related to their tolerance to Cd stress.

  14. Use Stress to Improve Your Job Performance.

    Science.gov (United States)

    Saville, Anthony; Kavina, George

    1982-01-01

    On-the-job stress can be constructive (eustress) or destructive (distress). A survey of 276 school superintendents in 13 western states identified their 10 most distressful situations, the frequency of job-related illnesses, their habits and personality types, and their methods of coping with stress. (RW)

  15. Stress induced alterations in pre-pubertal ovarian follicular development in rat

    Directory of Open Access Journals (Sweden)

    Yajurvedi H.N.

    2011-12-01

    Full Text Available The objective of the study was to find out whether stress experienced during neo-natal period alters the timing of formation of pre-antral and antral follicles and if so, whether pre-treatment with CRH receptor antagonist prevents these effects in rats. New born rat pups (n= 15 were exposed to maternal separation (6 hours/ day from post-natal day (PND 1 to 7 and were killed on PND 8, 11 and 15. The time of exposure was randomly changed every day during light phase (7Am to 7Pm of the day to avoid habituation. There was a significant increase in serum corticosterone levels on PND 8 and 11 in stress group rats compared to controls indicating stress response in these pups. The ovary of both control and stressed rats contained oocytes and primary follicles on PND 8 and 11 and in showed progress of follicular development upto to pre-antral and early antral follicle formation on PND 11 and 15. However, mean number of healthy oocytes and all categories of follicles at all ages studied were significantly lower in stressed rats compared to controls. Concomitant with these changes, number of atreatic follicles showed an increase over control values in stressed rats. The increase in atresia of follicles was due to apoptosis as shown by increase in the percentage of granulosa cells showing TUNEL positive staining and caspase 3 activity. On the other hand, pre-treatment with CRH- receptor antagonist (CRH 9-41 2ng/ 0.1 ml/ rat prior to undergoing stress regime on PND 1 to 7, prevented alterations in pre- pubertal follicular development thereby indicating that the ovarian changes were due to effects of stress induced activation of HPA axis. The results indicate that, stress during neonatal phase, though does not affect timing of formation of pre-antral and antral follicles, it does enhance atresia of follicles of all categories, including follicular reserve, which may affect the reproductive potential of adults. The results, for the first time reveal that CRF

  16. Nursing students’ perceived stress and influences in clinical performance

    Directory of Open Access Journals (Sweden)

    Laila Akhu-Zaheya

    2015-06-01

    Full Text Available Background: It is known that stress related to clinical training among nursing students could contribute to many physical and mental problems. However, little empirical evidence about the influence of stress in nurse students’ clinical performance Objective: The objective of this study was to assess the association between perceived stresses, stress related factors, and students’ clinical performance. Method: Using the perceived stress scale, 539 Jordanian nursing students from 2 public universities in Jordan participated in the study. Results: The results showed that the mean of stress perceived by students was 45.9. Students’ assignment were perceived as the main source of stress (M= 10.7, SD= 4.5 followed by stress related to patients’ care (M= 10.5, SD= 5.5 and stress from teachers and nursing staff (M= 9.6, SD= 5.3. The lowest source of stress is from students’ lack of professional knowledge and skills (M= 3.96; SD= 2.8. The mean of students’ clinical performance is 73.4%. Students’ perceived stress has a significant negative correlation with students’ clinical performance (r= -.09; p <.05. The results also showed significant negative correlation between stress related to lack of professional knowledge and skills, and stress related to patient care and students’ clinical performance. Conclusion: This study expanded on students’ stress in clinical settings, and warrants further research in assessing its impact on their performance. Teachers should be aware of and help students to overcome and cope with said stress related factors in the clinical settings effectively.

  17. Chronic stress effects in contralateral medial pterygoid muscle of rats with occlusion alteration.

    Science.gov (United States)

    Loyola, Bruno Melo; Nascimento, Glauce Crivelaro; Fernández, Rodrigo Alberto Restrepo; Iyomasa, Daniela Mizusaki; Pereira, Yamba Carla Lara; Leite-Panissi, Christie Ramos Andrade; Issa, João Paulo Mardegan; Iyomasa, Mamie Mizusaki

    2016-10-01

    +US groups, the deeply stained fibers increased compared to NO+C.·The exodontia factor was able to increase the ROS activity in muscle, whereas the stress factor does not significantly alter ROS in this tissue. It was concluded that both unpredictable chronic stress and the extraction induce metabolic and density of capillary changes in the contralateral medial pterygoid muscle to extraction, suggesting that these factors for a longer period of this experiment could induce muscle damage related to TMD. PMID:27342425

  18. Characterization of singlet oxygen-accumulating mutants isolated in a screen for altered oxidative stress response in Chlamydomonas reinhardtii

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    Eggen Rik IL

    2010-12-01

    Full Text Available Abstract Background When photosynthetic organisms are exposed to harsh environmental conditions such as high light intensities or cold stress, the production of reactive oxygen species like singlet oxygen is stimulated in the chloroplast. In Chlamydomonas reinhardtii singlet oxygen was shown to act as a specific signal inducing the expression of the nuclear glutathione peroxidase gene GPXH/GPX5 during high light stress, but little is known about the cellular mechanisms involved in this response. To investigate components affecting singlet oxygen signaling in C. reinhardtii, a mutant screen was performed. Results Mutants with altered GPXH response were isolated from UV-mutagenized cells containing a GPXH-arylsulfatase reporter gene construct. Out of 5500 clones tested, no mutant deficient in GPXH induction was isolated, whereas several clones showed constitutive high GPXH expression under normal light conditions. Many of these GPXH overexpressor (gox mutants exhibited higher resistance to oxidative stress conditions whereas others were sensitive to high light intensities. Interestingly, most gox mutants produced increased singlet oxygen levels correlating with high GPXH expression. Furthermore, different patterns of altered photoprotective parameters like non-photochemical quenching, carotenoid contents and α-tocopherol levels were detected in the various gox mutants. Conclusions Screening for mutants with altered GPXH expression resulted in the isolation of many gox mutants with increased singlet oxygen production, showing the relevance of controlling the production of this ROS in photosynthetic organisms. Phenotypic characterization of these gox mutants indicated that the mutations might lead to either stimulated triplet chlorophyll and singlet oxygen formation or reduced detoxification of singlet oxygen in the chloroplast. Furthermore, changes in multiple protection mechanisms might be responsible for high singlet oxygen formation and GPXH

  19. Environmental enrichment reduces behavioural alterations induced by chronic stress in Japanese quail.

    Science.gov (United States)

    Laurence, A; Houdelier, C; Calandreau, L; Arnould, C; Favreau-Peigné, A; Leterrier, C; Boissy, A; Lumineau, S

    2015-02-01

    Animals perceiving repeated aversive events can become chronically stressed. Chronic activation of the hypothalamic-pituitary-adrenal (HPA) axis can have deleterious consequences on physiological parameters (e.g. BW, blood chemistry) and behaviour (e.g. emotional reactivity, stereotypies, cognition). Environmental enrichment (EE) can be a mean to reduce animal stress and to improve welfare. The aim of this study was first, to assess the effects of EE in battery cages on the behaviour of young Japanese quail and second, to evaluate the impact of EE on quail exposed to chronic stress. The experiment involved quail housed in EE cages and submitted or not to a chronic stress procedure (CSP) (EE cages, control quail: n=16, CSP quail: n=14) and quail housed in standard cages and exposed or not to the CSP (standard non-EE cages, control quail: n=12, CSP quail: n=16). Our procedure consisted of repeated aversive events (e.g. ventilators, delaying access to food, physical restraint, noise) presented two to five times per 24 h, randomly, for 15 days. During CSP, EE improved quail's welfare as their stereotypic pacing decreased and they rested more. CSP decreased exploration in all quail. After the end of CSP, quail presented increased emotional reactivity in emergence test. However, the effect of EE varied with test. Finally, chronic stress effects on comfort behaviours in the emergence test were alleviated by EE. These results indicate that EE can alleviate some aspects of behavioural alterations induced by CSP. PMID:25354525

  20. Carbohydrate intake improves cognitive performance of stress-prone individuals under controllable laboratory stress

    NARCIS (Netherlands)

    Markus, C.R.; Panhuysen, G.; Jonkman, L.M.; Bachman, M.

    1999-01-01

    Cognitive performance has been found to decline after exposure to stress, particularly in stress-prone subjects. The present study investigated whether a carbohydrate-rich, protein-poor (CR/PP) diet, which may enhance cerebral serotonin function in stress-prone subjects due to increases in the avail

  1. Effect of yoga on academic performance in relation to stress

    Directory of Open Access Journals (Sweden)

    Kauts Amit

    2009-01-01

    Full Text Available Background: Academic performance is concerned with the quantity and quality of learning attained in a subject or group of subjects after a long period of instruction. Excessive stress hampers students′ performance. Improvement in academic performance and alertness has been reported in several yogic studies. Aims and Objectives: The main objective of the study was to assess the effect of yoga on academic performance in relation to stress. Materials and Methods: The study started with 800 adolescent students; 159 high-stress students and 142 low-stress students were selected on the basis of scores obtained through Stress Battery. Experimental group and control group were given pre test in three subjects, i.e., Mathematics, Science, and Social Studies. A yoga module consisting of yoga asanas, pranayama, meditation, and a value orientation program was administered on experimental group for 7 weeks. The experimental and control groups were post-tested for their performance on the three subjects mentioned above. Results: The results show that the students, who practiced yoga performed better in academics. The study further shows that low-stress students performed better than high-stress students, meaning thereby that stress affects the students′ performance.

  2. Coping with Mathematics Anxiety: Stress Management and Academic Performance.

    Science.gov (United States)

    Sime, Wesley E.; And Others

    1987-01-01

    Administered the Mathematics Anxiety Rating Scale to Introductory Statistics college students. A high mathematics anxiety was associated with lower performance on a statistics examination. Classroom stress-coping intervention reduced anxiety and physiological stress responses, but did not improve academic performance. (Author/KS)

  3. Oxidative Stress Alters miRNA and Gene Expression Profiles in Villous First Trimester Trophoblasts

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    Courtney E. Cross

    2015-01-01

    Full Text Available The relationship between oxidative stress and miRNA changes in placenta as a potential mechanism involved in preeclampsia (PE is not fully elucidated. We investigated the impact of oxidative stress on miRNAs and mRNA expression profiles of genes associated with PE in villous 3A first trimester trophoblast cells exposed to H2O2 at 12 different concentrations (0-1 mM for 0.5, 4, 24, and 48 h. Cytotoxicity, determined using the SRB assay, was used to calculate the IC50 of H2O2. RNA was extracted after 4 h exposure to H2O2 for miRNA and gene expression profiling. H2O2 exerted a concentration- and time-dependent cytotoxicity on 3A trophoblast cells. Short-term exposure of 3A cells to low concentration of H2O2 (5% of IC50 significantly altered miRNA profile as evidenced by significant changes in 195 out of 595 evaluable miRNAs. Tool for annotations of microRNAs (TAM analysis indicated that these altered miRNAs fall into 43 clusters and 34 families, with 41 functions identified. Exposure to H2O2 altered mRNA expression of 22 out of 84 key genes involved in dysregulation of placental development. In conclusion, short-term exposure of villous first trimester trophoblasts to low concentrations of H2O2 significantly alters miRNA profile and expression of genes implicated in placental development.

  4. Effect of yoga on academic performance in relation to stress

    OpenAIRE

    Kauts Amit; Sharma Neelam

    2009-01-01

    Background: Academic performance is concerned with the quantity and quality of learning attained in a subject or group of subjects after a long period of instruction. Excessive stress hampers students′ performance. Improvement in academic performance and alertness has been reported in several yogic studies. Aims and Objectives: The main objective of the study was to assess the effect of yoga on academic performance in relation to stress. Materials and Methods: The study started ...

  5. Correlation between Surgeon's experience, surgery complexity and the alteration of stress related physiological parameters.

    Directory of Open Access Journals (Sweden)

    Massimo Marrelli

    Full Text Available In the present work we analyzed the hormonal (salivary Cortisol; sC, immune (salivary Immunoglobulin A; sIgA and cardiovascular (Heart rate, HR, and systolic blood pressure, SBP responses induced by stress conditions in oral surgeons, randomly recruited according to their expertise level.Each surgeon performed three different surgical procedures with increasing degrees of technical difficulty and under time-limited conditions, to assess whether these variants may influence the risks of stress-induced secondary hypertension among the involved health professionals. sC and sIgA samples and cardiovascular function measurements were taken up before, during, and two hours after every surgery. Salivary samples and cardiovascular measurements were taken also during non-surgical days, as baseline controls.We observed that more experienced surgeons showed a higher stress management ability compared to those with less experience or, generally, younger, which are more exposed to the risks of developing secondary hypertension. Nevertheless, indipendently of sex and experience, oral surgeons are constantly exposed to high risks of developing stress-related diseases.On the basis of the issues addressed and the results obtained, we have highlighted the importance of the investigated stress biomarkers to monitor and to prevent stress-related pathologies among oral surgeons. This approach is aimed to emphasize the significance of these specific stress-biomarkers, which represent a powerful instrument to evaluate stress levels in oral surgeons, and that may help to reduce the most severe life-threatening risks to which they are daily exposed. In conclusion, final goal of this study is to suggest an useful guideline to monitor the stress levels of oral and maxillofacial surgeons in order to improve their quality of life, which is inevitably reflected on the quality of the performances provided and, finally, to prevent possible mistakes in their daily activities.

  6. The effect of occupational stress, psychological stress and burnout on employee performance: Evidence from banking industry

    OpenAIRE

    Shahram Hashemnia; Somayeh Abadiyan; Behnam Ghorbani Fard

    2014-01-01

    This paper presents an empirical investigation on the effects of occupational stress, psychological stress as well as job burnout on women’s employee performance in city of Karaj, Iran. The proposed study designs a questionnaire in Likert scale and distributes it among all female employees who worked for Bank Maskan in this city. In our survey, employee performance consists of three parts of interpersonal performance, job performance as well as organizational performance. Cronbach alpha has b...

  7. Prenatal stress alters progestogens to mediate susceptibility to sex-typical, stress-sensitive disorders, such as drug abuse: a review

    Directory of Open Access Journals (Sweden)

    Cheryl A Frye

    2011-10-01

    Full Text Available Maternal-offspring interactions begin prior to birth. Experiences of the mother during gestation play a powerful role in determining the developmental programming of the central nervous system. In particular, stress during gestation alters developmental programming of the offspring resulting in susceptibility to sex-typical and stress-sensitive neurodevelopmental, neuropsychiatric and neurodegenerative disorders. However, neither these effects, nor the underlying mechanisms, are well understood. Our hypothesis is that allopregnanolone, during gestation, plays a particularly vital role in mitigating effects of stress on the developing fetus and may mediate, in part, alterations apparent throughout the lifespan. Specifically, altered balance between glucocorticoids and progestogens during critical periods of development (stemming from psychological, immunological, and/or endocrinological stressors during gestation may permanently influence behavior, brain morphology, and/or neuroendocrine-sensitive processes. 5α-reduced progestogens are integral in the developmental programming of sex-typical, stress-sensitive, and/or disorder-relevant phenotypes. Prenatal stress may alter these responses and dysregulate allopregnanolone and its normative effects on stress axis function. As an example of a neurodevelopmental, neuropsychiatric and/or neurodegenerative process, this review focuses on responsiveness to drugs of abuse, which is sensitive to prenatal stress and progestogen milieu. This review explores the notion that allopregnanolone may effect, or be influenced by, prenatal stress, with consequences for neurodevelopmental-, neuropsychiatric- and/or neurodegenerative- relevant processes, such as addiction.

  8. Influence of carbonyl stress on rheological alterations of blood materials and decarbonylation effect of glutathione

    Institute of Scientific and Technical Information of China (English)

    彭密军; 蔡建光; 贺洪; 龚萍; 李国林; 汤婷; 朱泽瑞; 印大中

    2008-01-01

    The effects of various toxic carbonyls such as malondialdehyde(MDA),a secondary product of lipid peroxidation,and other aldehydes on rheological parameters and their relationship with aging-associated alterations were studied.Both MDA and glutaraldehyde(Glu) in different concentrations significantly increase viscosity,plastic viscosity and yield stress of human plasma and erythrocyte suspensions.MDA(20 mmol/L) reduces sharply the typical fluorescence of proteins(excitation 280 nm/emission 350 nm),and produces age pigment-like fluorescence with a strong emission peak at 460 nm when excites at 395 nm by only being incubated for some hours.In contrast,Glu decreases merely the fluorescence of proteins without producing age pigment-like fluorescence.These data suggest interestingly that the MDA-induced gradual protein cross linking seems to form from different mechanisms compared to the fast rheological changes of blood materials which may take place either in acute and chronic diseases or during aging.On the other hand,MDA induces various deleterious alterations of erythrocytes whereas glutathione(GSH) inhibits the MDA-related carbonyl stress in a concentration-dependent manner.The results indicate that carbonyl-amino reaction exists in the blood widely and GSH has the ability to interrupt or reverse this reaction in a certain way.It implies that carbonyl stress may be one of the important factors in blood stasis and suggests a theoretical and practical approach in anti-stresses and anti-aging.

  9. Whole transcriptome analysis of transgenic barley with altered cytokinin homeostasis and increased tolerance to drought stress.

    Science.gov (United States)

    Vojta, Petr; Kokáš, Filip; Husičková, Alexandra; Grúz, Jiří; Bergougnoux, Veronique; Marchetti, Cintia F; Jiskrová, Eva; Ježilová, Eliška; Mik, Václav; Ikeda, Yoshihisa; Galuszka, Petr

    2016-09-25

    Cytokinin plant hormones have been shown to play an important role in plant response to abiotic stresses. Herein, we expand upon the findings of Pospíšilová et al. [30] regarding preparation of novel transgenic barley lines overexpressing cytokinin dehydrogenase 1 gene from Arabidopsis under the control of mild root-specific promotor of maize β-glycosidase. These lines showed drought-tolerant phenotype mainly due to alteration of root architecture and stronger lignification of root tissue. A detailed transcriptomic analysis of roots of transgenic plants subjected to revitalization after drought stress revealed attenuated response through the HvHK3 cytokinin receptor and up-regulation of two transcription factors implicated in stress responses and abscisic acid sensitivity. Increased expression of several genes involved in the phenylpropanoid pathway as well as of genes encoding arogenate dehydratase/lyase participating in phenylalanine synthesis was found in roots during revitalization. Although more precursors of lignin synthesis were present in roots after drought stress, final lignin accumulation did not change compared to that in plants grown under optimal conditions. Changes in transcriptome indicated a higher auxin turnover in transgenic roots. The same analysis in leaves revealed that genes encoding putative enzymes responsible for production of jasmonates and other volatile compounds were up-regulated. Although transgenic barley leaves showed lower chlorophyll content and down-regulation of genes encoding proteins involved in photosynthesis than did wild-type plants when cultivated under optimal conditions, they did show a tendency to return to initial photochemical activities faster than did wild-type leaves when re-watered after severe drought stress. In contrast to optimal conditions, comparative transcriptomic analysis of revitalized leaves displayed up-regulation of genes encoding enzymes and proteins involved in photosynthesis, and especially

  10. Oxidative Stress in Retinal Muller Cells contributes to Dysfunction of Retinal Glutamate Uptake and Altered Protein Expression

    DEFF Research Database (Denmark)

    Toft-Kehler, Anne Katrine; Skytt, Dorte Marie; Kolko, Miriam

    2015-01-01

    minor, though significant, reduction of cell viability was seen after 1 and 24 hours of exposure to oxidative stress. The glutamate transporter, EAAT1, was significantly up-regulated at RNA-level after exposure to oxidative stress, whereas the alterations of superoxide dismutase 2 (SOD2) was time...

  11. High glucose alters retinal astrocytes phenotype through increased production of inflammatory cytokines and oxidative stress.

    Directory of Open Access Journals (Sweden)

    Eui Seok Shin

    Full Text Available Astrocytes are macroglial cells that have a crucial role in development of the retinal vasculature and maintenance of the blood-retina-barrier (BRB. Diabetes affects the physiology and function of retinal vascular cells including astrocytes (AC leading to breakdown of BRB. However, the detailed cellular mechanisms leading to retinal AC dysfunction under high glucose conditions remain unclear. Here we show that high glucose conditions did not induce the apoptosis of retinal AC, but instead increased their rate of DNA synthesis and adhesion to extracellular matrix proteins. These alterations were associated with changes in intracellular signaling pathways involved in cell survival, migration and proliferation. High glucose conditions also affected the expression of inflammatory cytokines in retinal AC, activated NF-κB, and prevented their network formation on Matrigel. In addition, we showed that the attenuation of retinal AC migration under high glucose conditions, and capillary morphogenesis of retinal endothelial cells on Matrigel, was mediated through increased oxidative stress. Antioxidant proteins including heme oxygenase-1 and peroxiredoxin-2 levels were also increased in retinal AC under high glucose conditions through nuclear localization of transcription factor nuclear factor-erythroid 2-related factor-2. Together our results demonstrated that high glucose conditions alter the function of retinal AC by increased production of inflammatory cytokines and oxidative stress with significant impact on their proliferation, adhesion, and migration.

  12. Curcumin Supplementation Decreases Intestinal Adiposity Accumulation, Serum Cholesterol Alterations, and Oxidative Stress in Ovariectomized Rats

    Science.gov (United States)

    Morrone, Maurilio da Silva; Schnorr, Carlos Eduardo; Behr, Guilherme Antônio; Gasparotto, Juciano; Bortolin, Rafael Calixto; da Boit Martinello, Katia; Saldanha Henkin, Bernardo; Rabello, Thallita Kelly; Zanotto-Filho, Alfeu; Gelain, Daniel Pens; Moreira, José Cláudio Fonseca

    2016-01-01

    The aim of this study was to investigate the potential of curcumin oral supplementation (50 and 100 mg/Kg/day, for 30 days) in circumventing menopause-associated oxidative stress and lipid profile dysfunctions in a rat ovariectomy (OVX) model. Female Wistar rats were operated and randomly divided into either sham-operated or OVX groups. Sham-operated group (n = 8) and one OVX group (n = 11) were treated with vehicle (refined olive oil), and the other two OVX groups received curcumin at 50 or 100 mg/Kg/day doses (n = 8/group). OVX vehicle-treated animals presented a higher deposition of intestinal adipose tissue as well as increased serum levels of IL-6, LDL, and total cholesterol when compared to sham-operated rats. In addition, several oxidative stress markers in serum, blood, and liver (such as TBARS, carbonyl, reduced-sulphydryl, and nonenzymatic antioxidant defenses) were altered toward a prooxidant status by OVX. Interestingly, curcumin supplementation attenuated most of these parameters to sham comparable values. Thus, the herein presented results show that curcumin may be useful to ameliorate lipid metabolism alterations and oxidative damage associated with hormone deprivation in menopause. PMID:26640615

  13. Prenatal stress alters the developmental pattern of behavioral indices of sexual maturation and copulation in male rats.

    Science.gov (United States)

    Hernández-Arteaga, Enrique; Hernández-González, Marisela; Rentería, Mayra Liliana Ramírez-; Almanza-Sepúlveda, Mayra Linné; Guevara, Miguel Angel; Silva, Marcela Arteaga; Jaime, Herlinda Bonilla

    2016-09-01

    Gestation and pre-puberty are critical periods during which several environmental factors can drastically affect the adequate development of subjects. Considering that stress is one of the most common factors to which subjects may be exposed during gestation, the present study evaluated the effects of prenatal stress on the behavioral indices of sexual maturation in male rats, including genital grooming (GG), preputial separation (PS), and spontaneous penile erections (SPE) during puberty, and on copulatory parameters during adulthood. Stress was exerted by immobilizing the female rats once per day for 2h from days 14-21 of pregnancy. The young rats born to the dams in the stressed group (SG) later presented a delayed occurrence of PS with a delayed onset and lower frequency and duration of GG compared to a control group (CG). Less than half of the subjects in SG presented SPE, and those that did showed delayed onset and lower frequency and duration. In adulthood, fewer subjects in SG showed sexual behavior responses (intromission and ejaculation), and their mount and intromission latencies on the first day they ejaculated were longer than those of the CG rats. Findings from this study provide additional evidence that stress caused by immobilization during the third period of pregnancy exerts a negative effect in the short-term (i.e., around puberty) by altering the typical development of GG and SPE and the occurrence of PS, while also demonstrating that this effect persists in the long-term, when it affects the performance of copulatory behavior in mature male rats. PMID:27174612

  14. Motor/autonomic stress responses in a competitive piano performance.

    Science.gov (United States)

    Yoshie, Michiko; Kudo, Kazutoshi; Ohtsuki, Tatsuyuki

    2009-07-01

    The present study examined the effects of psychological stress on performance quality, autonomic responses, and upper extremity muscle activity in skilled pianists through comparisons between stressful (competition) and nonstressful (rehearsal) conditions. We observed increased levels of subjective anxiety, autonomic arousal, and electromyographic activity in the competition condition, which could contribute to the impairment of performance quality. The results provide important practical implications for enhancing performance quality as well as preventing playing-related musculoskeletal disorders in musicians. PMID:19673810

  15. Mild Traumatic Brain Injury with Social Defeat Stress Alters Anxiety, Contextual Fear Extinction, and Limbic Monoamines in Adult Rats

    OpenAIRE

    Davies, Daniel R.; Olson, Dawne; Meyer, Danielle L.; Scholl, Jamie L.; Watt, Michael J.; Manzerra, Pasquale; Renner, Kenneth J.; Forster, Gina L.

    2016-01-01

    Mild traumatic brain injury (mTBI) produces symptoms similar to those typifying posttraumatic stress disorder (PTSD) in humans. We sought to determine whether a rodent model of stress concurrent with mTBI produces characteristics of PTSD such as impaired contextual fear extinction, while also examining concurrent alterations to limbic monoamine activity in brain regions relevant to fear and anxiety states. Male rats were exposed to social stress or control conditions immediately prior to mTBI...

  16. Mild traumatic brain injury with social defeat stress alters anxiety, contextual fear extinction, and limbic monoamines in adult rats

    OpenAIRE

    Daniel eDavies; Dawne eOlson; Danielle eMeyer; Jamie eScholl; Michael eWatt; Pasquale eManzerra; Kenneth eRenner; Forster, Gina L.

    2016-01-01

    Mild traumatic brain injury (mTBI) produces symptoms similar to those typifying posttraumatic stress disorder (PTSD) in humans. We sought to determine whether a rodent model of stress concurrent with mTBI produces characteristics of PTSD such as impaired contextual fear extinction, while also examining concurrent alterations to limbic monoamine activity in brain regions relevant to fear and anxiety states. Male rats were exposed to social stress or control conditions immediately prior to mT...

  17. Performance Stress and the Very Young Musician

    Science.gov (United States)

    Boucher, Helene; Ryan, Charlene A.

    2011-01-01

    Performance anxiety is a common experience among musicians. Recent studies have found it to be an issue not only for adult performers but also for developing musicians as early as third grade. The question as to its developed or innate nature led to the present inquiry pertaining to young children's responses to performance situations. Sixty-six…

  18. Inula crithmoides extract protects against ochratoxin A-induced oxidative stress, clastogenic and mutagenic alterations in male rats.

    Science.gov (United States)

    Abdel-Wahhab, Mosaad A; Abdel-Azim, Sekena H; El-Nekeety, Aziza A

    2008-09-15

    Ochratoxin A (OTA) is a mycotoxin often found in cereals and agricultural products. There is unequivocal evidence of renal carcinogenicity of OTA in male rats, although the mechanism of action is unknown. Several reports suggest that exposure to OTA resulted in oxidative stress, genotoxicity and DNA damage. Therefore, the aim of the current study was to evaluate the protective effects of aqueous extract of Inula crithmoides growing in Egypt against OTA-induced mutagenicity and oxidative stress. Forty male Sprague-Dawley rats were divided into four groups and treated for 15 days as follows: control group and the groups treated with OTA (3 mg/kg b.w), I. crithmoides extract alone (370 mg/kg b.w) and OTA+I. crithmoides extract. Blood and tissue samples were collected for different biochemical analyses. Bone marrow micronucleus test and blood for random amplified polymorphism DNA-PCR (RAPD-PCR) method were performed to assess the antigenotoxic effect of the extract. The results indicated that OTA induced toxicological effects typical to those reported in the literature and increased the frequencies of MnPCEs in bone marrow. The RAPD-PCR analysis revealed the appearance of new bands in DNA resulting from genetic alteration. The extract alone was safe and succeeded in counteracting the oxidative stress and protect against the cytotoxicity resulting from OTA. PMID:18694774

  19. Perfusion deficits and functional connectivity alterations in patients with post-traumatic stress disorder

    Science.gov (United States)

    Liu, Yang; Li, Baojuan; Zhang, Xi; Zhang, Linchuan; Li, Liang; Lu, Hongbing

    2016-03-01

    To explore the alteration in cerebral blood flow (CBF) and functional connectivity between survivors with recent onset post-traumatic stress disorder (PTSD) and without PTSD, survived from the same coal mine flood disaster. In this study, a processing pipeline using arterial spin labeling (ASL) sequence was proposed. Considering low spatial resolution of ASL sequence, a linear regression method was firstly used to correct the partial volume (PV) effect for better CBF estimation. Then the alterations of CBF between two groups were analyzed using both uncorrected and PV-corrected CBF maps. Based on altered CBF regions detected from the CBF analysis as seed regions, the functional connectivity abnormities in PTSD patients was investigated. The CBF analysis using PV-corrected maps indicates CBF deficits in the bilateral frontal lobe, right superior frontal gyrus and right corpus callosum of PTSD patients, while only right corpus callosum was identified in uncorrected CBF analysis. Furthermore, the regional CBF of the right superior frontal gyrus exhibits significantly negative correlation with the symptom severity in PTSD patients. The resting-state functional connectivity indicates increased connectivity between left frontal lobe and right parietal lobe. These results indicate that PV-corrected CBF exhibits more subtle perfusion changes and may benefit further perfusion and connectivity analysis. The symptom-specific perfusion deficits and aberrant connectivity in above memory-related regions may be putative biomarkers for recent onset PTSD induced by a single prolonged trauma exposure and help predict the severity of PTSD.

  20. Exposure to Forced Swim Stress Alters Local Circuit Activity and Plasticity in the Dentate Gyrus of the Hippocampus

    Directory of Open Access Journals (Sweden)

    Orli Yarom

    2008-01-01

    Full Text Available Studies have shown that, depending on its severity and context, stress can affect neural plasticity. Most related studies focused on synaptic plasticity and long-term potentiation (LTP of principle cells. However, evidence suggests that following high-frequency stimulation, which induces LTP in principal cells, modifications also take place at the level of complex interactions with interneurons within the dentate gyrus, that is, at the local circuit level. So far, the possible effects of stress on local circuit activity and plasticity were not studied. Therefore, we set out to examine the possible alterations in local circuit activity and plasticity following exposure to stress. Local circuit activity and plasticity were measured by using frequency dependant inhibition (FDI and commissural modulation protocols following exposure to a 15 minute-forced swim trial. Exposure to stress did not alter FDI. The application of theta-burst stimulation (TBS reduced FDI in both control and stressed rats, but this type of plasticity was greater in stressed rats. Commissural-induced inhibition was significantly higher in stressed rats both before and after applying theta-burst stimulation. These findings indicate that the exposure to acute stress affects aspects of local circuit activity and plasticity in the dentate gyrus. It is possible that these alterations underlie some of the behavioral consequences of the stress experience.

  1. When does stress help or harm? The effects of stress controllability and subjective stress response on Stroop performance.

    Directory of Open Access Journals (Sweden)

    Roselinde Kaiser Henderson

    2012-06-01

    Full Text Available The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing to clinical therapy. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, research suggests that the impact of stress on cognitive functioning depends on an individual’s response to stressors: moderate responses to stress can lead to improved performance while extreme (high or low responses can lead to impaired performance. The present studies tested the hypothesis that 1 learning to behaviorally control stressors leads to improved performance on a test of general executive functioning, the color-word Stroop, and that 2 this improvement emerges specifically for people who report moderate (subjective responses to stress. Experiment 1: Stroop performance, measured before and after a stress manipulation, was compared across groups of undergraduate participants (n=109. People who learned to control a noise stressor and received accurate performance feedback demonstrated reduced Stroop interference compared with people exposed to uncontrollable noise stress and feedback indicating an exaggerated rate of failure. In the group who learned behavioral control, those who reported moderate levels of stress showed the greatest reduction in Stroop interference. In contrast, in the group exposed to uncontrollable events, self-reported stress failed to predict performance. Experiment 2: In a second sample (n=90, we specifically investigated the role of controllability by keeping the rate of failure feedback constant across groups. In the group who learned behavioral control, those who reported moderate levels of stress

  2. Monocrotophos induced oxidative stress and alterations in brain dopamine and serotonin receptors in young rats.

    Science.gov (United States)

    Sankhwar, Madhu L; Yadav, Rajesh S; Shukla, Rajendra K; Singh, Dhirendra; Ansari, Reyaz W; Pant, Aditya B; Parmar, Devendra; Khanna, Vinay K

    2016-03-01

    Human exposure to monocrotophos, an organophosphate pesticide, could occur due to its high use in agriculture to protect crops. Recently, we found that postlactational exposure to monocrotophos impaired cholinergic mechanisms in young rats and such changes persisted even after withdrawal of monocrotophos exposure. In continuation to this, the effect of monocrotophos on noncholinergic targets and role of oxidative stress in its neurotoxicity has been studied. Exposure of rats from postnatal day (PD)22 to PD49 to monocrotophos (0.50 or 1.0 mg kg(-1) body weight, perorally) significantly impaired motor activity and motor coordination on PD50 as compared to controls. A significant decrease in the binding of (3)H-spiperone to striatal membrane (26%, p 0.05; 37%, p < 0.05) in those exposed at a higher dose, respectively, was observed on PD50 compared with the controls. Alterations in the binding persisted even after withdrawal of monocrotophos exposure on PD65. Increased oxidative stress in brain regions following exposure of rats to monocrotophos was also observed on PD50 that persisted 15 days after withdrawal of exposure on PD65. The results suggest that monocrotophos exerts its neurobehavioral toxicity by affecting noncholinergic functions involving dopaminergic and serotonergic systems associated with enhanced oxidative stress. The results also exhibit vulnerability of developing brain to monocrotophos as most of the changes persisted even after withdrawal of its exposure. PMID:24105069

  3. Skeletal Muscle Regeneration and Oxidative Stress Are Altered in Chronic Kidney Disease.

    Science.gov (United States)

    Avin, Keith G; Chen, Neal X; Organ, Jason M; Zarse, Chad; O'Neill, Kalisha; Conway, Richard G; Konrad, Robert J; Bacallao, Robert L; Allen, Matthew R; Moe, Sharon M

    2016-01-01

    Skeletal muscle atrophy and impaired muscle function are associated with lower health-related quality of life, and greater disability and mortality risk in those with chronic kidney disease (CKD). However, the pathogenesis of skeletal dysfunction in CKD is unknown. We used a slow progressing, naturally occurring, CKD rat model (Cy/+ rat) with hormonal abnormalities consistent with clinical presentations of CKD to study skeletal muscle signaling. The CKD rats demonstrated augmented skeletal muscle regeneration with higher activation and differentiation signals in muscle cells (i.e. lower Pax-7; higher MyoD and myogenin RNA expression). However, there was also higher expression of proteolytic markers (Atrogin-1 and MuRF-1) in CKD muscle relative to normal. CKD animals had higher indices of oxidative stress compared to normal, evident by elevated plasma levels of an oxidative stress marker, 8-hydroxy-2' -deoxyguanosine (8-OHdG), increased muscle expression of succinate dehydrogenase (SDH) and Nox4 and altered mitochondria morphology. Furthermore, we show significantly higher serum levels of myostatin and expression of myostatin in skeletal muscle of CKD animals compared to normal. Taken together, these data show aberrant regeneration and proteolytic signaling that is associated with oxidative stress and high levels of myostatin in the setting of CKD. These changes likely play a role in the compromised skeletal muscle function that exists in CKD. PMID:27486747

  4. Complexity and time asymmetry of heart rate variability are altered in acute mental stress

    International Nuclear Information System (INIS)

    We aimed to study the complexity and time asymmetry of short-term heart rate variability (HRV) as an index of complex neurocardiac control in response to stress using symbolic dynamics and time irreversibility methods. ECG was recorded at rest and during and after two stressors (Stroop, arithmetic test) in 70 healthy students. Symbolic dynamics parameters (NUPI, NCI, 0V%, 1V%, 2LV%, 2UV%), and time irreversibility indices (P%, G%, E) were evaluated. Additionally, HRV magnitude was quantified by linear parameters: spectral powers in low (LF) and high frequency (HF) bands. Our results showed a reduction of HRV complexity in stress (lower NUPI with both stressors, lower NCI with Stroop). Pattern classification analysis revealed significantly higher 0V% and lower 2LV% with both stressors, indicating a shift in sympathovagal balance, and significantly higher 1V% and lower 2UV% with Stroop. An unexpected result was found in time irreversibility: significantly lower G% and E with both stressors, P% index significantly declined only with arithmetic test. Linear HRV analysis confirmed vagal withdrawal (lower HF) with both stressors; LF significantly increased with Stroop and decreased with arithmetic test. Correlation analysis revealed no significant associations between symbolic dynamics and time irreversibility. Concluding, symbolic dynamics and time irreversibility could provide independent information related to alterations of neurocardiac control integrity in stress-related disease. (paper)

  5. How different types of participant payments alter task performance

    Directory of Open Access Journals (Sweden)

    Gary L. Brase

    2009-08-01

    Full Text Available Researchers typically use incentives (such as money or course credit in order to obtain participants who engage in the specific behaviors of interest to the researcher. There is, however, little understanding or agreement on the effects of different types and levels of incentives used. Some results in the domain of statistical reasoning suggest that performance differences --- previously deemed theoretically important --- may actually be due to differences in incentive types across studies. 704 participants completed one of five variants of a statistical reasoning task, for which they received either course credit, flat fee payment, or performance-based payment incentives. Successful task completion was more frequent with performance-based incentives than with either of the other incentive types. Performance on moderately difficult tasks (compared to very easy and very hard tasks was most sensitive to incentives. These results can help resolve existing debates about inconsistent findings, guide more accurate comparisons across studies, and be applied beyond research settings.

  6. Stress and its impact on a performance at work

    OpenAIRE

    Kamenská, Zuzana

    2013-01-01

    This bachelor´s thesis is primarily concerned with the impact of stress on a person’s performance in the work environment. In today´s hectic times and technological advancements stress is no longer a term coined by modern times, but it has also become an integral part of our everyday life. People are exposed to a great number of everyday stressful situations the occurrence of which they can barely influence. However, a thorough knowledge of stress can impact the duration and intensity of stre...

  7. Overcoming the effects of stress on reactor operator performance

    Energy Technology Data Exchange (ETDEWEB)

    He Xuhong; Wei Li; Zhao Bingquan [Tsinghua Univ., Nuclear Power Plant Simulation Training Center, Beijing (China)

    2003-03-01

    Reactor operators may be exposed to significant levels of stress during plant emergencies and their performance may be affected by the stress. This paper first identified the potential sources of stress in the nuclear power plant, then discussed the ways in which stress is likely to affect the reactor operators, and finally identified several training approaches for reducing or eliminating stress effects. The challenges for effective stress reducing training may seem daunting, yet the challenges are real and must be addressed. This paper reviewed researches in training design, knowledge and skill acquisition, and training transfer point to a number of strategies that can be used to address these challenges and lead to more effective training and development. (author)

  8. Overcoming the effects of stress on reactor operator performance

    International Nuclear Information System (INIS)

    Reactor operators may be exposed to significant levels of stress during plant emergencies and their performance may be affected by the stress. This paper first identified the potential sources of stress in the nuclear power plant, then discussed the ways in which stress is likely to affect the reactor operators, and finally identified several training approaches for reducing or eliminating stress effects. The challenges for effective stress reducing training may seem daunting, yet the challenges are real and must be addressed. This paper reviewed researches in training design, knowledge and skill acquisition, and training transfer point to a number of strategies that can be used to address these challenges and lead to more effective training and development. (author)

  9. Stress response and humoral immune system alterations related to chronic hypergravity in mice.

    Science.gov (United States)

    Guéguinou, Nathan; Bojados, Mickaël; Jamon, Marc; Derradji, Hanane; Baatout, Sarah; Tschirhart, Eric; Frippiat, Jean-Pol; Legrand-Frossi, Christine

    2012-01-01

    Spaceflights are known to induce stress and immune dysregulation. Centrifugation, as hindlimb unloading, is a good ground based-model to simulate altered gravity which occurs during space missions. The aim of this study was to investigate the consequences of a long-term exposure to different levels of hypergravity on the stress response and the humoral immunity in a mouse model. For this purpose, adult C57Bl/6J male mice were subjected for 21 days either to control conditions or to 2G or 3G acceleration gravity forces. Corticosterone level and anxiety behavior revealed a stress response which was associated with a decrease of body weight, after 21-day of centrifugation at 3G but not at 2G. Spleen lymphocyte lipopolysaccharide (LPS) responsiveness was diminished by 40% in the 2G group only, whereas a decrease was noted when cells were stimulated with concanavalin A for both 2G and 3G groups (about 25% and 20%, respectively) compared to controls. Pro-inflammatory chemokines (MCP-1 and IP-10) and Th1 cytokines (IFNγ and IL2) were slightly decreased in the 2G group and strongly decreased in the 3G mouse group. Regarding Th2 cytokines (IL4, IL5) no further significant modification was observed, whereas the immunosuppressive cytokine IL10 was slightly increased in the 3G mice. Finally, serum IgG concentration was twice higher whereas IgA concentration was slightly increased (about 30%) and IgM were unchanged in 2G mice compared to controls. No difference was observed in the 3G group with these isotypes. Consequently, functional immune dysregulations and stress responses were dependent of the gravity level. PMID:21724335

  10. How different types of participant payments alter task performance

    OpenAIRE

    Brase, Gary L.

    2009-01-01

    Researchers typically use incentives (such as money or course credit) in order to obtain participants who engage in the specific behaviors of interest to the researcher. There is, however, little understanding or agreement on the effects of different types and levels of incentives used. Some results in the domain of statistical reasoning suggest that performance differences --- previously deemed theoretically important --- may actually be due to differences in incentive types across studies. ...

  11. Expectancy of Stress-Reducing Aromatherapy Effect and Performance on a Stress-Sensitive Cognitive Task

    Directory of Open Access Journals (Sweden)

    Irina Chamine

    2015-01-01

    Full Text Available Objective. Stress-reducing therapies help maintain cognitive performance during stress. Aromatherapy is popular for stress reduction, but its effectiveness and mechanism are unclear. This study examined stress-reducing effects of aromatherapy on cognitive function using the go/no-go (GNG task performance and event related potentials (ERP components sensitive to stress. The study also assessed the importance of expectancy in aromatherapy actions. Methods. 81 adults were randomized to 3 aroma groups (active experimental, detectable, and undetectable placebo and 2 prime subgroups (prime suggesting stress-reducing aroma effects or no-prime. GNG performance, ERPs, subjective expected aroma effects, and stress ratings were assessed at baseline and poststress. Results. No specific aroma effects on stress or cognition were observed. However, regardless of experienced aroma, people receiving a prime displayed faster poststress median reaction times than those receiving no prime. A significant interaction for N200 amplitude indicated divergent ERP patterns between baseline and poststress for go and no-go stimuli depending on the prime subgroup. Furthermore, trends for beneficial prime effects were shown on poststress no-go N200/P300 latencies and N200 amplitude. Conclusion. While there were no aroma-specific effects on stress or cognition, these results highlight the role of expectancy for poststress response inhibition and attention.

  12. Expectancy of stress-reducing aromatherapy effect and performance on a stress-sensitive cognitive task.

    Science.gov (United States)

    Chamine, Irina; Oken, Barry S

    2015-01-01

    Objective. Stress-reducing therapies help maintain cognitive performance during stress. Aromatherapy is popular for stress reduction, but its effectiveness and mechanism are unclear. This study examined stress-reducing effects of aromatherapy on cognitive function using the go/no-go (GNG) task performance and event related potentials (ERP) components sensitive to stress. The study also assessed the importance of expectancy in aromatherapy actions. Methods. 81 adults were randomized to 3 aroma groups (active experimental, detectable, and undetectable placebo) and 2 prime subgroups (prime suggesting stress-reducing aroma effects or no-prime). GNG performance, ERPs, subjective expected aroma effects, and stress ratings were assessed at baseline and poststress. Results. No specific aroma effects on stress or cognition were observed. However, regardless of experienced aroma, people receiving a prime displayed faster poststress median reaction times than those receiving no prime. A significant interaction for N200 amplitude indicated divergent ERP patterns between baseline and poststress for go and no-go stimuli depending on the prime subgroup. Furthermore, trends for beneficial prime effects were shown on poststress no-go N200/P300 latencies and N200 amplitude. Conclusion. While there were no aroma-specific effects on stress or cognition, these results highlight the role of expectancy for poststress response inhibition and attention. PMID:25802539

  13. Post-traumatic stress disorder, dissociation, and neuropsychological performance in Latina victims of childhood sexual abuse.

    Science.gov (United States)

    Rivera-Vélez, Giselle M; González-Viruet, Maribella; Martínez-Taboas, Alfonso; Pérez-Mojica, Deborah

    2014-01-01

    This study compared the memory, attention/concentration, and executive functioning of 12 women with histories of child sexual abuse with a control group of 12 women without childhood abuse. Participants completed a neuropsychological test battery and various instruments assessing post-traumatic stress disorder and dissociation. The child sexual abuse group had lower performance than the control group on long- and short-term visual and verbal memory and presented more limited performance on executive functioning tasks. Functioning in these areas showed a negative correlation with post-traumatic stress disorder and dissociative symptoms. These findings suggest that child sexual abuse is associated with memory and executive functioning deficits and supports the idea that people with trauma histories and increased post-traumatic stress disorder and dissociation symptoms may have alterations in neuropsychological functioning. PMID:24393090

  14. Fluoxetine alters reproductive performance of female fighting fish, Betta splendens

    Directory of Open Access Journals (Sweden)

    Mohammad Navid Forsatkar

    2014-07-01

    Full Text Available This study was aimed to investigate the effects of waterborne fluoxetine on the reproduction performance of female fighting fish (Betta splendens. For this purpose, mature, ready for spawning females were exposed to concentrations of 0, 0.54 and 54.0 µg/l fluoxetine for 7 days. Then they were introduced into the spawning tank containing pre-acclimated male and reproductive consequences including number of copulations per spawning, number of eggs per copulation, duration of spawning, fecundity and hatching rate were assessed. Fluoxetine concentration of 54.0 µg/l, was significantly affected on the number of produced eggs per copulation, fecundity and hatching rate. In addition, the mean number of copulations per spawning was not different between treatments but significantly different for the spawning duration between control and 54.0 µg/l treatments. The results suggest that fluoxetine can impacts on reproductive performance of female fighting fish at concentrations greater than those found in the aquatic environments.

  15. Fluoxetine Treatment Rescues Energy Metabolism Pathway Alterations in a Posttraumatic Stress Disorder Mouse Model.

    Science.gov (United States)

    Kao, Chi-Ya; He, Zhisong; Henes, Kathrin; Asara, John M; Webhofer, Christian; Filiou, Michaela D; Khaitovich, Philipp; Wotjak, Carsten T; Turck, Christoph W

    2016-05-01

    Posttraumatic stress disorder (PTSD) is a prevalent psychiatric disorder. Several studies have attempted to characterize molecular alterations associated with PTSD, but most findings were limited to the investigation of specific cellular markers in the periphery or defined brain regions. In the current study, we aimed to unravel affected molecular pathways/mechanisms in the fear circuitry associated with PTSD. We interrogated a foot shock-induced PTSD mouse model by integrating proteomics and metabolomics profiling data. Alterations at the proteome level were analyzed using in vivo (15)N metabolic labeling combined with mass spectrometry in the prelimbic cortex (PrL), anterior cingulate cortex (ACC), basolateral amygdala, central nucleus of the amygdala and CA1 of the hippocampus between shocked and nonshocked (control) mice, with and without fluoxetine treatment. In silico pathway analyses revealed an upregulation of the citric acid cycle pathway in PrL, and downregulation in ACC and nucleus accumbens (NAc). Chronic fluoxetine treatment prevented decreased citric acid cycle activity in NAc and ACC and ameliorated conditioned fear response in shocked mice. Our results shed light on the role of energy metabolism in PTSD pathogenesis and suggest potential therapy through mitochondrial targeting. PMID:27606320

  16. ORGANIZATIONAL STRESS AND ITS IMPACT ON WORK PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Costin Madalina - Adriana

    2011-07-01

    Full Text Available Nowadays, in times of economic crisis, most managers or entrepreneurs have to cope with a lot of new job challenges which can easily transform into stressors. Work related stress is of growing concern because it has significant economic implications for the organization. Even if some stress is a normal part of life, excessive stress can influence one's productivity, health and emotions and it has to be taken under control. When people lose confidence, they refuse to take responsibilities, they get quickly irritated, they are unsatisfied of their job, their performance will be very low and the organization will be in danger. Fortunately, most managers and entrepreneurs know which stress main symptoms are and have the necessary knowledge for managing and reducing it before it can affect employees' daily work. Stress can have an impact both on the organizational welfare and on personal behavior of supervisors or employees, that's why, the ability of managing it can make the difference between job's success or failure. The purpose of this paper is to study Romanian managers and entrepreneurs from Bihor County's perception regarding the stress phenomenon, if they feel that they are affected by stress, if they promote some methods to reduce it and if they consider that stress can influence the organizational performance. As a research method we used an online questionnaire, applied to a number of 75 managers and entrepreneurs that represent the target group of the project "Flexibility and performance through management", project financed by the European Social Fund - "Invest in people". Each participant had to answer a number of 35 questions regarding stress and the results will be presented in this paper. The main conclusion is that, even if job itself is seen as a stressor, there are other important factors that can produce stress such as: family problems, personal problems or social problems.

  17. Job stress and job performance controversy: an empirical assessment.

    Science.gov (United States)

    Jamal, M

    1984-02-01

    This study examined the relationship between job stress and employees' performance and withdrawal behavior among nurses (N = 440) in two hospitals in a metropolitan Canadian city on the east coast. Job stressors assessed included role ambiguity, role overload, role conflict, and resource inadequacy. Employees' performance was operationalized in terms of job performance, motivation, and patient care skill. Withdrawal behaviors assessed were absenteeism, tardiness, and anticipated turnover. Multiple regressions, curvilinear correlation coefficients, and canonical correlations were computed to test the nature of the relationship between stressors and the criterion variables of the study. In general, data were more supportive of the negative linear relationship between stress and performance than for positive linear or curvilinear relationship. However, the stressor role ambiguity did exhibit a monotonic nonlinear relationship with a number of criterion variables. Employees' professional and organizational commitment were proposed to moderate the stress-performance relationship. However, the data only partially supported the role of the moderators. PMID:10265480

  18. Altered Mitochondrial Function and Oxidative Stress in Leukocytes of Anorexia Nervosa Patients

    OpenAIRE

    Victor, Victor M.; Rovira-Llopis, Susana; Saiz-Alarcon, Vanessa; Sangüesa, Maria C.; Rojo-Bofill, Luis; Bañuls, Celia; Falcón, Rosa; Castelló, Raquel; Rojo, Luis; Rocha, Milagros; Hernández-Mijares, Antonio

    2014-01-01

    Context Anorexia nervosa is a common illness among adolescents and is characterised by oxidative stress. Objective The effects of anorexia on mitochondrial function and redox state in leukocytes from anorexic subjects were evaluated. Design and setting A multi-centre, cross-sectional case-control study was performed. Patients Our study population consisted of 20 anorexic patients and 20 age-matched controls, all of which were Caucasian women. Main outcome measures Anthropometric and metabolic...

  19. Correlation between Surgeon's Experience, Surgery Complexity and the Alteration of Stress Related Physiological Parameters

    OpenAIRE

    Marrelli, Massimo; Gentile, Stefano; Palmieri, Francesca; Paduano, Francesco; Tatullo, Marco

    2014-01-01

    Introduction In the present work we analyzed the hormonal (salivary Cortisol; sC), immune (salivary Immunoglobulin A; sIgA) and cardiovascular (Heart rate, HR, and systolic blood pressure, SBP) responses induced by stress conditions in oral surgeons, randomly recruited according to their expertise level. Materials and methods Each surgeon performed three different surgical procedures with increasing degrees of technical difficulty and under time-limited conditions, to assess whether these var...

  20. Estrogen alters proenkephalin RNAs in the paraventricular nucleus of the hypothalamus following stress.

    Science.gov (United States)

    Yukhananov, R Y; Handa, R J

    1997-08-01

    Gonadal steroids modulate activity of the hypothalamo-pituitary-adrenal axis (HPA) following stress, but the regulatory pathways of this modulation are unknown. A possible site of action is the synthesis of CRH and/or enkephalin in cells of the paraventricular nucleus of the hypothalamus (PVN). To investigate this possibility, we utilized two stressors, i.p. hypertonic saline injection (HSI) or exposure to novel environment, and examined the response of CRH or c-fos mRNAs and proenkephalin (PPE) mRNA and heteronuclear RNA (hnRNA, primary transcript). Male rats were gonadectomized and treated with estrogen or dihydrotestosterone propionate (DHTP) for 2 weeks. In situ hybridization revealed that novelty or HSI elevated levels of PPE hnRNA and c-fos mRNA in the PVN. Estrogen attenuated the elevation of PPE hnRNA in the PVN following HSI, and enhanced the c-fos mRNA response to novelty. In contrast, DHTP did not affect PPE hnRNA, but inhibited the c-fos mRNA response to novelty. These data indicate that in male rats estrogen receptor but not androgen receptor may modulate the endocrine stress response by altering PPE transcription in the PVN and that this effect depends on the type of stressor. PMID:9295199

  1. Prenatal stress causes alterations in the morphology of microglia and the inflammatory response of the hippocampus of adult female mice

    Directory of Open Access Journals (Sweden)

    Diz-Chaves Yolanda

    2012-04-01

    Full Text Available Abstract Background Stress during fetal life increases the risk of affective and immune disorders later in life. The altered peripheral immune response caused by prenatal stress may impact on brain function by the modification of local inflammation. In this study we have explored whether prenatal stress results in alterations in the immune response in the hippocampus of female mice during adult life. Methods Pregnant C57BL/6 mice were subjected three times/day during 45 minutes to restraint stress from gestational Day 12 to delivery. Control non-stressed pregnant mice remained undisturbed. At four months of age, non-stressed and prenatally stressed females were ovariectomized. Fifteen days after surgery, mice received an i.p. injection of vehicle or of 5 mg/kg of lipopolysaccharide (LPS. Mice were sacrificed 20 hours later by decapitation and the brains were removed. Levels of interleukin-1β (IL1β, interleukin-6 (IL-6, tumor necrosis factor α (TNF-α, interferon γ-inducible protein 10 (IP10, and toll-like receptor 4 mRNA were assessed in the hippocampus by quantitative real-time polymerase chain reaction. Iba1 immunoreactivity was assessed by immunocytochemistry. Statistical significance was determined by one-way or two-way analysis of variance. Results Prenatal stress, per se, increased IL1β mRNA levels in the hippocampus, increased the total number of Iba1-immunoreactive microglial cells and increased the proportion of microglial cells with large somas and retracted cellular processes. In addition, prenatally stressed and non-stressed animals showed different responses to peripheral inflammation induced by systemic administration of LPS. LPS induced a significant increase in mRNA levels of IL-6, TNF-α and IP10 in the hippocampus of prenatally stressed mice but not of non-stressed animals. In addition, after LPS treatment, prenatally stressed animals showed a higher proportion of Iba1-immunoreactive cells in the hippocampus with

  2. Prenatal Stress Alters Progestogens to Mediate Susceptibility to Sex-Typical, Stress-Sensitive Disorders, such as Drug Abuse: A Review

    OpenAIRE

    Frye, Cheryl A.; Paris, Jason J.; Osborne, Danielle M.; Campbell, Joannalee C.; Kippin, Tod E.

    2011-01-01

    Maternal–offspring interactions begin prior to birth. Experiences of the mother during gestation play a powerful role in determining the developmental programming of the central nervous system. In particular, stress during gestation alters developmental programming of the offspring resulting in susceptibility to sex-typical and stress-sensitive neurodevelopmental, neuropsychiatric, and neurodegenerative disorders. However, neither these effects, nor the underlying mechanisms, are well underst...

  3. Prenatal stress alters progestogens to mediate susceptibility to sex-typical, stress-sensitive disorders, such as drug abuse: a review

    OpenAIRE

    Frye, Cheryl A.; Paris, Jason J.; Danielle eOsborne; Joanna eCampbell; Tod eKippin

    2011-01-01

    Maternal-offspring interactions begin prior to birth. Experiences of the mother during gestation play a powerful role in determining the developmental programming of the central nervous system. In particular, stress during gestation alters developmental programming of the offspring resulting in susceptibility to sex-typical and stress-sensitive neurodevelopmental, neuropsychiatric and neurodegenerative disorders. However, neither these effects, nor the underlying mechanisms, are well unders...

  4. Hypoxia/oxidative stress alters the pharmacokinetics of CPU86017-RS through mitochondrial dysfunction and NADPH oxidase activation

    OpenAIRE

    Gao, Jie; Ding, Xuan-Sheng; Zhang, Yu-mao; Dai, De-zai; Liu, Mei; Zhang, Can; Dai, Yin

    2013-01-01

    Aim: Hypoxia/oxidative stress can alter the pharmacokinetics (PK) of CPU86017-RS, a novel antiarrhythmic agent. The aim of this study was to investigate the mechanisms underlying the alteration of PK of CPU86017-RS by hypoxia/oxidative stress. Methods: Male SD rats exposed to normal or intermittent hypoxia (10% O2) were administered CPU86017-RS (20, 40 or 80 mg/kg, ig) for 8 consecutive days. The PK parameters of CPU86017-RS were examined on d 8. In a separate set of experiments, female SD ra...

  5. Repeated exposure of adult rats to transient oxidative stress induces various long-lasting alterations in cognitive and behavioral functions.

    Directory of Open Access Journals (Sweden)

    Yoshio Iguchi

    Full Text Available Exposure of neonates to oxidative stress may increase the risk of psychiatric disorders such as schizophrenia in adulthood. However, the effects of moderate oxidative stress on the adult brain are not completely understood. To address this issue, we systemically administrated 2-cyclohexen-1-one (CHX to adult rats to transiently reduce glutathione levels. Repeated administration of CHX did not affect the acquisition or motivation of an appetitive instrumental behavior (lever pressing rewarded by a food outcome under a progressive ratio schedule. In addition, response discrimination and reversal learning were not affected. However, acute CHX administration blunted the sensitivity of the instrumental performance to outcome devaluation, and this effect was prolonged in rats with a history of repeated CHX exposure, representing pro-depression-like phenotypes. On the other hand, repeated CHX administration reduced immobility in forced swimming tests and blunted acute cocaine-induced behaviors, implicating antidepressant-like effects. Multivariate analyses segregated a characteristic group of behavioral variables influenced by repeated CHX administration. Taken together, these findings suggest that repeated administration of CHX to adult rats did not cause a specific mental disorder, but it induced long-term alterations in behavioral and cognitive functions, possibly related to specific neural correlates.

  6. The effect of occupational stress, psychological stress and burnout on employee performance: Evidence from banking industry

    Directory of Open Access Journals (Sweden)

    Shahram Hashemnia

    2014-09-01

    Full Text Available This paper presents an empirical investigation on the effects of occupational stress, psychological stress as well as job burnout on women’s employee performance in city of Karaj, Iran. The proposed study designs a questionnaire in Likert scale and distributes it among all female employees who worked for Bank Maskan in this city. In our survey, employee performance consists of three parts of interpersonal performance, job performance as well as organizational performance. Cronbach alpha has been used to verify the overall questionnaire, all components were within acceptable levels, and the implementation of Kolmogorov-Smirnov test has indicated that the data were not normally distributed. Using Spearman correlation ratio as well as regression techniques, the study has determined that while psychological stress influenced significantly on all three components of employee performance including interpersonal performance, job performance as well as organizational performance, the effect on job performance was greater than the other components. In addition, occupational stress only influences on organizational as well as interpersonal performance. Finally, employee burnout has no impact on any components of employee performance.

  7. Think aloud: acute stress and coping strategies during golf performances.

    Science.gov (United States)

    Nicholls, Adam R; Polman, Remco C J

    2008-07-01

    A limitation of the sport psychology coping literature is the amount of time between a stressful episode and the recall of the coping strategies used in the stressful event (Nicholls & Polman, 2007). The purpose of this study was to develop and implement a technique to measure acute stress and coping during performance. Five high-performance adolescent golfers took part in Level 2 verbalization think aloud trials (Ericsson & Simon, 1993), which involved participants verbalizing their thoughts, over six holes of golf. Verbal reports were audio-recorded during each performance, transcribed verbatim, and analyzed using protocol analysis (Ericsson & Simon, 1993). Stressors and coping strategies varied throughout the six holes, which support the proposition that stress and coping is a dynamic process that changes across phases of the same performance (Lazarus, 1999). The results also revealed information regarding the sequential patterning of stress and coping, suggesting that the golfers experienced up to five stressors before reporting a coping strategy. Think aloud appears a suitable method to collect concurrent stress and coping data. PMID:18612855

  8. An ambient agent model for analyzing managers' performance during stress

    Science.gov (United States)

    ChePa, Noraziah; Aziz, Azizi Ab; Gratim, Haned

    2016-08-01

    Stress at work have been reported everywhere. Work related performance during stress is a pattern of reactions that occurs when managers are presented with work demands that are not matched with their knowledge, skills, or abilities, and which challenge their ability to cope. Although there are many prior findings pertaining to explain the development of manager performance during stress, less attention has been given to explain the same concept through computational models. In such, a descriptive nature in psychological theories about managers' performance during stress can be transformed into a causal-mechanistic stage that explains the relationship between a series of observed phenomena. This paper proposed an ambient agent model for analyzing managers' performance during stress. Set of properties and variables are identified through past literatures to construct the model. Differential equations have been used in formalizing the model. Set of equations reflecting relations involved in the proposed model are presented. The proposed model is essential and can be encapsulated within an intelligent agent or robots that can be used to support managers during stress.

  9. Algorithms Based on CWT and Classifiers to Control Cardiac Alterations and Stress Using an ECG and a SCR

    OpenAIRE

    Amaia Méndez Zorrilla; Begoña García Zapirain; María Viqueira Villarejo

    2013-01-01

    This paper presents the results of using a commercial pulsimeter as an electrocardiogram (ECG) for wireless detection of cardiac alterations and stress levels for home control. For these purposes, signal processing techniques (Continuous Wavelet Transform (CWT) and J48) have been used, respectively. The designed algorithm analyses the ECG signal and is able to detect the heart rate (99.42%), arrhythmia (93.48%) and extrasystoles (99.29%). The detection of stress level is complemented with Ski...

  10. Social Isolation Stress Induces Anxious-Depressive-Like Behavior and Alterations of Neuroplasticity-Related Genes in Adult Male Mice

    OpenAIRE

    Alessandro Ieraci; Alessandra Mallei; Maurizio Popoli

    2016-01-01

    Stress is a major risk factor in the onset of several neuropsychiatric disorders including anxiety and depression. Although several studies have shown that social isolation stress during postweaning period induces behavioral and brain molecular changes, the effects of social isolation on behavior during adulthood have been less characterized. Aim of this work was to investigate the relationship between the behavioral alterations and brain molecular changes induced by chronic social isolation ...

  11. Performance demonstration tests for detection of intergranular stress corrosion cracking

    International Nuclear Information System (INIS)

    This report evaluates detection tests of inservice inspectors (ISI), procedures and equipment that are employed to find intergranular stress corrosion cracks in nuclear power plant piping. Performance is described by two fundamental parameters: false call probability and probability of detection. Acceptable inspection performance and detection tests are therefore defined in terms of these two parameters. 14 refs., 25 figs

  12. Predator odor stress alters corticotropin-releasing factor-1 receptor (CRF1R)-dependent behaviors in rats.

    Science.gov (United States)

    Roltsch, Emily A; Baynes, Brittni B; Mayeux, Jacques P; Whitaker, Annie M; Baiamonte, Brandon A; Gilpin, Nicholas W

    2014-04-01

    Humans with stress-related anxiety disorders exhibit increases in arousal and alcohol drinking, as well as altered pain processing. Our lab has developed a predator odor stress model that produces reliable and lasting increases in alcohol drinking. Here, we utilize this predator odor stress model to examine stress-induced increases in arousal, nociceptive processing, and alcohol self-administration by rats, and also to determine the effects of corticotropin-releasing factor-1 receptors (CRF1Rs) in mediating these behavioral changes. In a series of separate experiments, rats were exposed to predator odor stress, then tested over subsequent days for thermal nociception in the Hargreaves test, acoustic startle reactivity, or operant alcohol self-administration. In each experiment, rats were systemically injected with R121919, a CRF1R antagonist, and/or vehicle. Predator odor stress increased thermal nociception (i.e., hyperalgesia) and acoustic startle reactivity. Systemic administration of R121919 reduced thermal nociception and hyperarousal in stressed rats but not unstressed controls, and reduced operant alcohol responding over days. Stressed rats exhibited increased sensitivity to the behavioral effects of R121919 in all three tests, suggesting up-regulation of brain CRF1Rs number and/or function in stressed rats. These results suggest that post-stress alcohol drinking may be driven by a high-nociception high-arousal state, and that brain CRF1R signaling mediates these stress effects. PMID:24269607

  13. Investigating The Effect Of Job Stress On Performance Of Employees

    OpenAIRE

    Oyungerel Altangerel; Wang Ruimei; Ehsan Elahi; Bayandalai Dash

    2015-01-01

    Abstract This study is conducted to investigate the effect of job stress on job performance. A random sampling technique is used to collect primary data of 120 employees of four telecommunication companies of Mongolia i.e. Mobicom Unitel Skytel and G-mobile. A well-structured questionnaire is utilized to collect relevant data descriptive and logistic analysis is used to estimate and describe the findings of results. It is found that work overload is major reason of stress among employees and ...

  14. Altered brain morphology and functional connectivity reflect a vulnerable affective state after cumulative multigenerational stress in rats.

    Science.gov (United States)

    McCreary, J Keiko; Truica, L Sorina; Friesen, Becky; Yao, Youli; Olson, David M; Kovalchuk, Igor; Cross, Albert R; Metz, Gerlinde A S

    2016-08-25

    Prenatal stress is a risk factor for abnormal neuroanatomical, cognitive, behavioral and mental health outcomes with potentially transgenerational consequences. Females in general seem more resilient to the effects of prenatal stress than males. Here, we examined if repeated stress across generations may diminish stress resiliency and cumulatively enhance the susceptibility for adverse health outcomes in females. Pregnant female rats of three successive generations were exposed to stress from gestational days 12-18 to generate multigenerational prenatal stress (MPS) in the maternal lineage. Stress response was measured by plasma corticosterone levels and open-field exploration in each generation. Neuromorphological consequences of MPS were investigated in the F3 generation using in vivo manganese-enhanced magnetic resonance imaging (MEMRI), T2-relaxometry, and cytoarchitectonics in relation to candidate gene expression involved in brain plasticity and mental health. Each additional generation of prenatal stress incrementally elevated hypothalamic-pituitary-adrenal axis activation, anxiety-like and aversive behaviors in adult female offspring. Elevated stress responses in the MPS F3 generation were accompanied by reduced neural density in prefrontal cortex, hippocampus and whole brain along with altered brain activation patterns in in vivo MEMRI. MPS increased ephrin receptor A5 (Epha5), neuronal growth regulator (Negr1) and synaptosomal-associated protein 25 (Snap25) gene expression and reduced fibroblast growth factor 12 (Fgf12) in prefrontal cortex. These genes regulate neuronal maturation, arborization and synaptic plasticity and may explain altered brain cytoarchitectonics and connectivity. These findings emphasize that recurrent stress across generations may cumulatively increase stress vulnerability and the risk of adverse health outcomes through perinatal programing in females. PMID:27241944

  15. Effects of exercise training on stress-induced vascular reactivity alterations: role of nitric oxide and prostanoids

    Directory of Open Access Journals (Sweden)

    Thiago Bruder-Nascimento

    2015-06-01

    Full Text Available Background: Physical exercise may modify biologic stress responses. Objective: To investigate the impact of exercise training on vascular alterations induced by acute stress, focusing on nitric oxide and cyclooxygenase pathways. Method: Wistar rats were separated into: sedentary, trained (60-min swimming, 5 days/week during 8 weeks, carrying a 5% body-weight load, stressed (2 h-immobilization, and trained/stressed. Response curves for noradrenaline, in the absence and presence of L-NAME or indomethacin, were obtained in intact and denuded aortas (n=7-10. Results: None of the procedures altered the denuded aorta reactivity. Intact aortas from stressed, trained, and trained/stressed rats showed similar reduction in noradrenaline maximal responses (sedentary 3.54±0.15, stressed 2.80±0.10*, trained 2.82±0.11*, trained/stressed 2.97± 0.21*, *P<0.05 relate to sedentary. Endothelium removal and L-NAME abolished this hyporeactivity in all experimental groups, except in trained/stressed rats that showed a partial aorta reactivity recovery in L-NAME presence (L-NAME: sedentary 5.23±0,26#, stressed 5.55±0.38#, trained 5.28±0.30#, trained/stressed 4.42±0.41, #P<0.05 related to trained/stressed. Indomethacin determined a decrease in sensitivity (EC50 in intact aortas of trained rats without abolishing the aortal hyporeactivity in trained, stressed, and trained/stressed rats. Conclusions: Exercise-induced vascular adaptive response involved an increase in endothelial vasodilator prostaglandins and nitric oxide. Stress-induced vascular adaptive response involved an increase in endothelial nitric oxide. Beside the involvement of the endothelial nitric oxide pathway, the vascular response of trained/stressed rats involved an additional mechanism yet to be elucidated. These findings advance on the understanding of the vascular processes after exercise and stress alone and in combination.

  16. Alteration of hepatic structure and oxidative stress induced by intravenous nanoceria

    Energy Technology Data Exchange (ETDEWEB)

    Tseng, Michael T., E-mail: mttsen01@louisville.edu [Dept of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky (United States); Lu, Xiaoqin, E-mail: x0lu0003@louisville.edu [Dept of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky (United States); Duan, Xiaoxian, E-mail: x0duan02@louisville.edu [Dept of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky (United States); Hardas, Sarita S., E-mail: sarita.hardas@uky.edu [Dept. of Chemistry, University of Kentucky, Lexington, Kentucky (United States); Sultana, Rukhsana, E-mail: rsult2@uky.edu [Dept. of Chemistry, University of Kentucky, Lexington, Kentucky (United States); Wu, Peng, E-mail: peng.wu@uky.edu [Dept of Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky (United States); Unrine, Jason M., E-mail: jason.unrine@uky.edu [Dept of Plant and Soil Sciences, University of Kentucky, Lexington, Kentucky (United States); Graham, Uschi, E-mail: graham@caer.uky.edu [Center for Applied Energy Research, University of Kentucky, Lexington, Kentucky (United States); Butterfield, D. Allan, E-mail: dabcns@uky.edu [Dept. of Chemistry, University of Kentucky, Lexington, Kentucky (United States); Grulke, Eric A., E-mail: eric.grulke@uky.edu [Dept of Chemical and Materials Engineering, University of Kentucky, Lexington, Kentucky (United States); Yokel, Robert A., E-mail: ryokel@email.uky.edu [Department of Pharmaceutical Sciences, University of Kentucky, Lexington, Kentucky (United States)

    2012-04-15

    Beyond the traditional use of ceria as an abrasive, the scope of nanoceria applications now extends into fuel cell manufacturing, diesel fuel additives, and for therapeutic intervention as a putative antioxidant. However, the biological effects of nanoceria exposure have yet to be fully defined, which gave us the impetus to examine its systemic biodistribution and biological responses. An extensively characterized nanoceria (5 nm) dispersion was vascularly infused into rats, which were terminated 1 h, 20 h or 30 days later. Light and electron microscopic tissue characterization was conducted and hepatic oxidative stress parameters determined. We observed acute ceria nanoparticle sequestration by Kupffer cells with subsequent bioretention in parenchymal cells as well. The internalized ceria nanoparticles appeared as spherical agglomerates of varying dimension without specific organelle penetration. In hepatocytes, the agglomerated nanoceria frequently localized to the plasma membrane facing bile canaliculi. Hepatic stellate cells also sequestered nanoceria. Within the sinusoids, sustained nanoceria bioretention was associated with granuloma formations comprised of Kupffer cells and intermingling CD3{sup +} T cells. A statistically significant elevation of serum aspartate aminotransferase (AST) level was seen at 1 and 20 h, but subsided by 30 days after ceria administration. Further, elevated apoptosis was observed on day 30. These findings, together with increased hepatic protein carbonyl levels on day 30, indicate ceria-induced hepatic injury and oxidative stress, respectively. Such observations suggest a single vascular infusion of nanoceria can lead to persistent hepatic retention of particles with possible implications for occupational and therapeutic exposures. -- Highlights: ► Time course study on nanoceria induced hepatic alterations in rats. ► Serum AST elevation indicated acute hepatotoxicity. ► Ceria is retained for up to 30 days in Kupffer cells

  17. Prenatal stress induces alterations in cerebellar nitric oxide that are correlated with deficits in spatial memory in rat's offspring.

    Science.gov (United States)

    Maur, Damián G; Romero, Carolina B; Burdet, Berenice; Palumbo, María L; Zorrilla-Zubilete, María A

    2012-12-01

    Prenatal stress (PS) has been linked to abnormal cognitive, behavioral and psychosocial outcomes in both animals and humans. Since PS has been shown to induce a cerebellar cytoarchitectural disarrangement and cerebellar abnormalities that have been linked to an impairment of behavioral functions, the aim of the present work was to investigate whether the exposure to PS in a period in which the cerebellum is still immature can induce behavioral deficits in the adult and whether this alterations are correlated with changes in nitric oxide (NO) and cellular oxidative mechanisms in offspring's cerebellum. Our results show impairments in spatial memory and territory discrimination in PS adult rats. PS offspring also displayed alterations in cerebellar nitric oxide synthase (NOS) expression and activity. Moreover, a correlation between spatial memory deficits and the increase in NOS activity was found. The results found here may point to a role of cerebellar NO in the behavioral alterations induced by stress during early development stages. PMID:23022609

  18. Relationship between mental toughness, stress appraisal, and innovation performance of R&D personnel

    Directory of Open Access Journals (Sweden)

    Feng Jin

    2016-01-01

    Full Text Available Four hundred and two R&D personnel were surveyed through questionnaires to study the relationship between mental toughness, stress appraisal (including experience of stress and stress control, and innovation performance. The findings reveal a significant negative correlation between mental toughness and stress experience and a significant positive correlation between mental toughness and both stress control and innovation performance. Furthermore, although the experience of stress was negatively correlated with innovation performance, stress control had the opposite effect. Experience of stress and stress control were the mediating variables for mental toughness and innovation performance, respectively. There was also a significant interaction effect between stress appraisal and mental toughness.

  19. Altered mitochondrial function and oxidative stress in leukocytes of anorexia nervosa patients.

    Directory of Open Access Journals (Sweden)

    Victor M Victor

    Full Text Available CONTEXT: Anorexia nervosa is a common illness among adolescents and is characterised by oxidative stress. OBJECTIVE: The effects of anorexia on mitochondrial function and redox state in leukocytes from anorexic subjects were evaluated. DESIGN AND SETTING: A multi-centre, cross-sectional case-control study was performed. PATIENTS: Our study population consisted of 20 anorexic patients and 20 age-matched controls, all of which were Caucasian women. MAIN OUTCOME MEASURES: Anthropometric and metabolic parameters were evaluated in the study population. To assess whether anorexia nervosa affects mitochondrial function and redox state in leukocytes of anorexic patients, we measured mitochondrial oxygen consumption, membrane potential, reactive oxygen species production, glutathione levels, mitochondrial mass, and complex I and III activity in polymorphonuclear cells. RESULTS: Mitochondrial function was impaired in the leukocytes of the anorexic patients. This was evident in a decrease in mitochondrial O2 consumption (P<0.05, mitochondrial membrane potential (P<0.01 and GSH levels (P<0.05, and an increase in ROS production (P<0.05 with respect to control subjects. Furthermore, a reduction of mitochondrial mass was detected in leukocytes of the anorexic patients (P<0.05, while the activity of mitochondrial complex I (P<0.001, but not that of complex III, was found to be inhibited in the same population. CONCLUSIONS: Oxidative stress is produced in the leukocytes of anorexic patients and is closely related to mitochondrial dysfunction. Our results lead us to propose that the oxidative stress that occurs in anorexia takes place at mitochondrial complex I. Future research concerning mitochondrial dysfunction and oxidative stress should aim to determine the physiological mechanism involved in this effect and the physiological impact of anorexia.

  20. Investigating The Effect Of Job Stress On Performance Of Employees

    Directory of Open Access Journals (Sweden)

    Oyungerel Altangerel

    2015-02-01

    Full Text Available Abstract This study is conducted to investigate the effect of job stress on job performance. A random sampling technique is used to collect primary data of 120 employees of four telecommunication companies of Mongolia i.e. Mobicom Unitel Skytel and G-mobile. A well-structured questionnaire is utilized to collect relevant data descriptive and logistic analysis is used to estimate and describe the findings of results. It is found that work overload is major reason of stress among employees and majority of employees reduce their productivity and loss of interest in job due to stress. As for concern health issue eyes strain dizziness and disorder in sleep are due to job stress. According to results of logit model parameters of education experience and salary per month are statistically significant and have positive impact on employees performance but age family size no relaxation time giving to employees during working hours and work overload are statistically significant and have negative impact on employees job performance. For suggestions companies should increase salaries of employees and give reward to employees those have work overload. Workload of employees should reduce by proper work redesign and efficient management by proper allocation of job. It is also found that stress also becomes reason of several illnesses and majority of employees dont have medical facilities first aid at working place therefore it is suggested that companies should also provide medical facilities first aid for employees at work place.

  1. Altered resting-state functional activity in posttraumatic stress disorder: A quantitative meta-analysis.

    Science.gov (United States)

    Wang, Ting; Liu, Jia; Zhang, Junran; Zhan, Wang; Li, Lei; Wu, Min; Huang, Hua; Zhu, Hongyan; Kemp, Graham J; Gong, Qiyong

    2016-01-01

    Many functional neuroimaging studies have reported differential patterns of spontaneous brain activity in posttraumatic stress disorder (PTSD), but the findings are inconsistent and have not so far been quantitatively reviewed. The present study set out to determine consistent, specific regional brain activity alterations in PTSD, using the Effect Size Signed Differential Mapping technique to conduct a quantitative meta-analysis of resting-state functional neuroimaging studies of PTSD that used either a non-trauma (NTC) or a trauma-exposed (TEC) comparison control group. Fifteen functional neuroimaging studies were included, comparing 286 PTSDs, 203 TECs and 155 NTCs. Compared with NTC, PTSD patients showed hyperactivity in the right anterior insula and bilateral cerebellum, and hypoactivity in the dorsal medial prefrontal cortex (mPFC); compared with TEC, PTSD showed hyperactivity in the ventral mPFC. The pooled meta-analysis showed hypoactivity in the posterior insula, superior temporal, and Heschl's gyrus in PTSD. Additionally, subgroup meta-analysis (non-medicated subjects vs. NTC) identified abnormal activation in the prefrontal-limbic system. In meta-regression analyses, mean illness duration was positively associated with activity in the right cerebellum (PTSD vs. NTC), and illness severity was negatively associated with activity in the right lingual gyrus (PTSD vs. TEC). PMID:27251865

  2. Diallyl tetrasulfide improves cadmium induced alterations of acetylcholinesterase, ATPases and oxidative stress in brain of rats

    International Nuclear Information System (INIS)

    Cadmium (Cd) is a neurotoxic metal, which induces oxidative stress and membrane disturbances in nerve system. The garlic compound diallyl tetrasulfide (DTS) has the cytoprotective and antioxidant activity against Cd induced toxicity. The present study was carried out to investigate the efficacy of DTS in protecting the Cd induced changes in the activity of acetylcholinesterase (AChE), membrane bound enzymes, lipid peroxidation (LPO) and antioxidant status in the brain of rats. In rats exposed to Cd (3 mg/kg/day subcutaneously) for 3 weeks, a significant (P +K+-ATPase, Mg2+-ATPase and Ca2+-ATPase) were observed in brain tissue. Oral administration of DTS (40 mg/kg/day) with Cd significantly (P < 0.05) diminished the levels of LPO and protein carbonyls and significantly (P < 0.05) increased the activities of ATPases, antioxidant enzymes, GSH and TSH in brain. These results indicate that DTS attenuate the LPO and alteration of antioxidant and membrane bound enzymes in Cd exposed rats, which suggest that DTS protects the brain function from toxic effects of Cd

  3. Alterations in empathic responding among women with posttraumatic stress disorder associated with childhood trauma

    Science.gov (United States)

    Parlar, Melissa; Frewen, Paul; Nazarov, Anthony; Oremus, Carolina; MacQueen, Glenda; Lanius, Ruth; McKinnon, Margaret C

    2014-01-01

    Objective Although studies increasingly point toward problems with social cognition among individuals with posttraumatic stress disorder (PTSD), few studies have assessed empathic responding. The aim of the current study was to investigate empathic responding in women with PTSD related to childhood trauma, and the contribution of parental bonding to empathic abilities in this sample. Methods Participants with PTSD (n = 29) and sex- and age-matched healthy controls (n = 20) completed two self-report empathy measures, the Interpersonal Reactivity Index (IRI) and the Toronto Empathy Questionnaire (TEQ), and a self-report measure of attachment, the Parental Bonding Instrument (PBI). Results Women with PTSD, relative to controls, reported significantly lower levels of empathic concern (r = 0.29) and perspective taking (r = 0.30), yet significantly higher levels of personal distress (r = 0.45) on the IRI. Women with PTSD also reported elevated scores on the TEQ (η2 = 0.13). Levels of paternal care on the PBI, rather than childhood trauma severity or PTSD symptom severity best predicted perspective taking scores on the IRI in the PTSD sample (R2 = 0.20). Conclusion Women with PTSD associated with childhood trauma reported alterations among different domains of empathic functioning that may be related to low levels of paternal care. PMID:24944867

  4. Combined neonicotinoid pesticide and parasite stress alter honeybee queens' physiology and survival.

    Science.gov (United States)

    Dussaubat, Claudia; Maisonnasse, Alban; Crauser, Didier; Tchamitchian, Sylvie; Bonnet, Marc; Cousin, Marianne; Kretzschmar, André; Brunet, Jean-Luc; Le Conte, Yves

    2016-01-01

    Honeybee colony survival strongly relies on the queen to overcome worker losses exposed to combined stressors like pesticides and parasites. Queen's capacity to withstand these stressors is however very little known. The effects of the common neonicotinoid pesticide imidacloprid in a chronic and sublethal exposure together with the wide distributed parasite Nosema ceranae have therefore been investigated on queen's physiology and survivorship in laboratory and field conditions. Early physiological changes were observed on queens, particularly the increase of enzyme activities (catalase [CAT] and glutathione-S-transferase [GST] in the heads) related to protective responses to xenobiotics and oxidative stress against pesticide and parasite alone or combined. Stressors also alter the activity of two other enzymes (carboxylesterase alpha [CaE α] and carboxylesterase para [CaE p] in the midguts) involved in metabolic and detoxification functions. Furthermore, single and combined effects of pesticide and parasite decrease survivorship of queens introduced into mating hives for three months. Because colony demographic regulation relies on queen's fertility, the compromise of its physiology and life can seriously menace colony survival under pressure of combined stressors. PMID:27578396

  5. Oxidative stress and alterations in actin cytoskeleton trigger glutathione efflux in Saccharomyces cerevisiae.

    Science.gov (United States)

    Bradamante, Silvia; Villa, Alessandro; Versari, Silvia; Barenghi, Livia; Orlandi, Ivan; Vai, Marina

    2010-12-01

    A marked deficiency in glutathione (GSH), the most abundant antioxidant in living systems, plays a major role in aging and the pathogenesis of diseases ranging from neurological disorders to early atherosclerosis and the impairment of various immunological functions. In an attempt to shed light on GSH homeostasis, we carried out the space experiment SCORE (Saccharomyces cerevisiae oxidative stress response evaluation) during the FOTON-M3 mission. Microgravity and hyperoxic conditions induced an enormous extracellular release of GSH from S. cerevisiae cells (≈40% w/dw), changed the distribution of the buds, and activated the high osmolarity glycerol (HOG) and cell integrity/PKC pathways, as well as protein carbonylation. The results from the single spaceflight experiment were validated by a complete set of experiments under conditions of simulated microgravity and indicate that cytoskeletal alterations are mainly responsible for the observed effects. The results of ground experiments in which we induced cytoskeletal modifications by means of treatment with dihydrocytochalasin B (DHCB), a potent inhibitor of actin polymerisation, or (R)-(+)-trans-4-(1-aminoethyl)-N-(4-pyridyl)cyclohexanecarboxamide dihydrochloride monohydrate (Y-27632), a selective ROCK (Rho-associated coiled-coil forming protein serine/threonine kinase) inhibitor, confirmed the role of actin in GSH efflux. We also found that the GSH release can be inhibited using the potent chloride channel blocker 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB). PMID:20708643

  6. Mercury Induced Biochemical Alterations As Oxidative Stress In Mugil Cephalus In Short Term Toxicity Test

    Directory of Open Access Journals (Sweden)

    J.S.I Rajkumar

    2013-04-01

    Full Text Available Mugil cephalus juveniles of size 2.5 ±0.6cm were exposed to mercury in short term chronic toxicity test through static renewal bioassay to detect the possible biochemical agent as biomarkers in aquatic pollution and in estuarine contamination as specific. Lipid peroxidation levels, glutathione S -transferase, catalase, reduced glutathione and acetylcholinesterase were studied as biochemical parameters. Increased thio-barbituric acid reactive substances levels were observed under exposure to mercury, leading to the oxidative damage resulting in lipid peroxidation. Decreased activities of antioxidants, catalase and increased glutathione-S-transferase under short term chronic exposures to mercury were more prominent in metal stress suggesting activation of physiological mechanism to scavenge the ROS produced. Decreased values of reduced glutathione on prolonged exposures to mercury indicate utilization of this antioxidant, either to scavenge oxy-radical or act in combination with other enzymes. The acetylcholinesterase activity was found to be decreased during mercury exposure. The results also suggest that mercury alters the active oxygen metabolism by modulating antioxidant enzyme activities, which can be used as biomarker to detect sub-lethal effects in aquatic pollution

  7. Combined neonicotinoid pesticide and parasite stress alter honeybee queens’ physiology and survival

    Science.gov (United States)

    Dussaubat, Claudia; Maisonnasse, Alban; Crauser, Didier; Tchamitchian, Sylvie; Bonnet, Marc; Cousin, Marianne; Kretzschmar, André; Brunet, Jean-Luc; Le Conte, Yves

    2016-01-01

    Honeybee colony survival strongly relies on the queen to overcome worker losses exposed to combined stressors like pesticides and parasites. Queen’s capacity to withstand these stressors is however very little known. The effects of the common neonicotinoid pesticide imidacloprid in a chronic and sublethal exposure together with the wide distributed parasite Nosema ceranae have therefore been investigated on queen’s physiology and survivorship in laboratory and field conditions. Early physiological changes were observed on queens, particularly the increase of enzyme activities (catalase [CAT] and glutathione-S-transferase [GST] in the heads) related to protective responses to xenobiotics and oxidative stress against pesticide and parasite alone or combined. Stressors also alter the activity of two other enzymes (carboxylesterase alpha [CaE α] and carboxylesterase para [CaE p] in the midguts) involved in metabolic and detoxification functions. Furthermore, single and combined effects of pesticide and parasite decrease survivorship of queens introduced into mating hives for three months. Because colony demographic regulation relies on queen’s fertility, the compromise of its physiology and life can seriously menace colony survival under pressure of combined stressors. PMID:27578396

  8. Involvement of Nitric Oxide, Neurotrophins and HPA Axis in Neurobehavioural Alterations Induced by Prenatal Stress.

    Science.gov (United States)

    Maur, Damian G; Pascuan, Cecilia G; Genaro, Ana M; Zorrilla-Zubilete, Maria A

    2015-01-01

    Several studies suggest that negative emotions during pregnancy generate adverse effects on the cognitive, behavioural and emotional development of the descendants. The psychoneuroendocrine pathways involve the transplacentary passage of maternal glucocorticoids in order to influence directly on fetal growth and brain development.Nitric oxide is a gaseous neurotransmitter that plays an important role in the control of neural activity by diffusing into neurons and participates in learning and memory processes. It has been demonstrated that nitric oxide is involved in the regulation of corticosterone secretion. Thus, it has been found that the neuronal isoform of nitric oxide synthase (nNOS) is an endogenous inhibitor of glucocorticoid receptor (GR) in the hippocampus and that nNOS in the hippocampus may participate in the modulation of hypothalamic-pituitary-adrenal axis activity via GR.Neurotrophins are a family of secreted growth factors consisting of nerve growth factor (NGF), brain-derived neurotrophic factor (BDNF), neurotrophin 3 (NT3) and NT4. Although initially described in the nervous system, they regulate processes such as cell survival, proliferation and differentiation in several other compartments. It has been demonstrated that the NO-citrulline cycle acts together with BDNF in maintaining the progress of neural differentiation.In the present chapter, we explore the interrelation between nitric oxide, glucocorticoids and neurotrophins in brain areas that are key structures in learning and memory processes. The participation of this interrelation in the behavioural and cognitive alterations induced in the offspring by maternal stress is also addressed. PMID:25287536

  9. Thermal, physiological and perceptual strain mediate alterations in match-play tennis under heat stress

    Science.gov (United States)

    Périard, Julien D; Racinais, Sébastien; Knez, Wade L; Herrera, Christopher P; Christian, Ryan J; Girard, Olivier

    2014-01-01

    Objectives This study compared the thermal, physiological and perceptual responses associated with match-play tennis in HOT (∼34°C wet-bulb-globe temperature (WBGT)) and COOL (∼19°C WBGT) conditions, along with the accompanying alterations in match characteristics. Methods 12 male tennis players undertook two matches for an effective playing time (ie, ball in play) of 20 min, corresponding to ∼119 and ∼102 min of play in HOT and COOL conditions, respectively. Rectal and skin temperatures, heart rate, subjective ratings of thermal comfort, thermal sensation and perceived exertion were recorded, along with match characteristics. Results End-match rectal temperature increased to a greater extent in the HOT (∼39.4°C) compared with the COOL (∼38.7°C) condition (ptennis characteristics under severe heat stress appear to represent a behavioural strategy adopted to minimise or offset the sensation of environmental conditions being rated as difficult. PMID:24668377

  10. Altered stress fibers and integrin expression in the Malpighian epithelium of Drosophila type IV collagen mutants.

    Science.gov (United States)

    Kiss, András A; Popovics, Nikoletta; Szabó, Gábor; Csiszár, Katalin; Mink, Mátyás

    2016-06-01

    Basement membranes (BMs) are highly specialized extracellular matrices (ECMs) that provide support and polarization cues for epithelial cells. Proper adhesion to the BM is pivotal in epithelial cell function and survival. Type IV collagens are the predominant components of all types of BMs, that form an irregular, polygonal lattice and serve as a scaffold for numerous other BM components and BM-associated cells. Mutations in the ubiquitous human BM components COL4A1 and COL4A2 cause a multisystem disorder involving nephropathy. Affected patients develop renal dysfunction and chronic kidney failure with or without hematuria. Mouse Col4a1 and Col4a2 mutants recapitulate the human symptoms. In vertebrates, excretion is accomplished by the kidneys and by the Malpighian tubules in insects, including the fruit fly Drosophila. Our present results with dominant, temperature-sensitive mutation of the Drosophila col4a1 gene demonstrate altered integrin expression and amplified effects of mechanical stress on the Malpighian epithelial cytoskeleton. PMID:27077087

  11. Adrenocortical responsiveness to infusions of physiological doses of ACTH is not altered in posttraumatic stress disorder

    Directory of Open Access Journals (Sweden)

    M. Michele Murburg

    2009-10-01

    Full Text Available Early studies of posttraumatic stress disorder (PTSD reported that abnormal function of the hypothalamic-pituitary-adrenocortical (HPA system was associated with the disorder. However, subsequent studies attempting to identify a specific aspect of HPA dysfunction that characterizes PTSD have been marked by considerable inconsistency of results. A facet of HPA regulation that has been considered but not definitively investigated is the possibility that the responsiveness of the adrenal cortex to physiological concentrations of ACTH is diminished in PTSD. Relationships between PTSD and the adrenal androgen dehydroepiandrosterone (DHEA have also been postulated. In this study we investigated the magnitude and time course of changes in concentrations of plasma cortisol and DHEA in response to bolus infusions of physiological doses of ACTH 1-24 in PTSD patients and control subjects. We found no evidence for PTSD-related alterations in cortisol or DHEA secretion in response to stimulation by low doses of ACTH and conclude that adrenocortical responsiveness is normal in PTSD. Results from this and other studies suggest that the occurrence of defects in HPA function in PTSD may be specific responses to particular combinations of trauma type, genetic susceptibility, and individual history.

  12. Assay of alterations in oxidative stress markers in pigs naturally infested with Sarcoptes scabiei var. suis.

    Science.gov (United States)

    Dimri, Umesh; Bandyopadhyay, S; Singh, Shanker Kumar; Ranjan, Rakesh; Mukherjee, R; Yatoo, M I; Patra, P H; De, U K; Dar, A A

    2014-09-15

    The present study aimed to examine the status of antioxidant systems of the pigs naturally suffering from sarcoptic mange. Fifty nine pigs were divided into three groups, healthy control (group I, n=15), subclinical sarcoptic mange (group II, n=22) and clinical sarcoptic mange (group III, n=22). To assess the status of antioxidant systems; lipid peroxides (LPO), reduced glutathione (GSH), superoxide dismutase (SOD), glutathione peroxidase (GPx), ascorbic acid, zinc and copper concentrations in the blood samples as well as LPO, SOD, CAT and glutathione-s-transferase (GST) activities in the skin were measured. The GSH, SOD, GPx, ascorbic acid, zinc, copper concentrations in blood were significantly lower in the pigs suffering from clinical and subclinical sarcoptic mange, when compared with the healthy control. However, LPO content of these infested pigs was significantly higher. The CAT, SOD and GST activities in the skin of the diseased pigs were significantly lower, whereas LPO was significantly higher as compared to the healthy control. From the present study, it may be concluded that sarcoptic mange bestows remarkable alterations in the oxidative stress markers and imposes compromisation of the antioxidant status of the infested pigs. PMID:24986463

  13. Tolerance and responsive gene expression of Sogatella furcifera under extreme temperature stresses are altered by its vectored plant virus.

    Science.gov (United States)

    Xu, Donglin; Zhong, Ting; Feng, Wendi; Zhou, Guohui

    2016-01-01

    Southern rice black-streaked dwarf virus (SRBSDV), a newly emerged fijivirus causing great loss to rice production in eastern and southeastern Asian countries in recent years, is efficiently transmitted by a rice pest, white-backed planthopper (WBPH, Sogatella furcifera) in a persistent, circulative propagative manner and can be considered as an insect virus. In this study, SRBSDV infection in WBPH was found to increase the vector's death rate under extreme cold stress but improve its survival rate under extreme heat stress. Digital gene expression profiling based on RNA-Seq revealed different gene regulation patterns in WBPH under viral and/or temperature stress. Under cold stress, the virus infection upregulated 1540 genes and downregulated 131 genes in the insect, most of which were related to membrane properties and biological processes of actin and cytoskeleton; whereas under heat stress, it upregulated 363 genes and downregulated 548 genes, most of which were associated to metabolism and intracellular organelles. Several types of stress-responsive genes involving intestinal mucin, cuticle protein, ubiquitin protease, immune response, RNA interference and heat shock response, were largely upregulated under cold stress, but largely downregulated under heat stress, by SRBSDV infection. Our results suggest two distinct mechanisms of virus-altered vector insect tolerance to temperature stress. PMID:27531640

  14. Predicting Performance Under Acute Stress : The Role of Individual Characteristics

    NARCIS (Netherlands)

    Delahaij, R.; Dam, K. van; Gaillard, A.W.K.; Soeters, J.

    2011-01-01

    This prospective study examined how differences in coping style, coping self-efficacy, and metacognitive awareness influence coping behavior and performance during a realistic acute stressful exercise in 2 military samples (n = 122 and n = 132). Results showed that coping self-efficacy and coping st

  15. Academic Performance and Perceived Stress among University Students

    Science.gov (United States)

    Talib, Nadeem; Zia-ur-Rehman, Muhammad

    2012-01-01

    This study aims to investigate the effect of factor such as perceived stress on the academic performance of the students. A sample of 199 university graduates and undergraduates in Rawalpindi and Islamabad was selected as a statistical frame. Instrumentation used for this study is previously validated construct in order to evaluate the effect of…

  16. Predicting Performance Under Stressful Conditions Using Galvanic Skin Response

    OpenAIRE

    Mundell, Carter; Vielma, Juan Pablo; Zaman, Tauhid

    2016-01-01

    The rapid growth of the availability of wearable biosensors has created the opportunity for using biological signals to measure worker performance. An important question is how to use such signals to not just measure, but actually predict worker performance on a task under stressful and potentially high risk conditions. Here we show that the biological signal known as galvanic skin response (GSR) allows such a prediction. We conduct an experiment where subjects answer arithmetic questions und...

  17. Moringa oleifera extract enhances sexual performance in stressed rats.

    Science.gov (United States)

    Prabsattroo, Thawatchai; Wattanathorn, Jintanaporn; Iamsaard, Sitthichai; Somsapt, Pichet; Sritragool, Opass; Thukhummee, Wipawee; Muchimapura, Supaporn

    2015-03-01

    Aphrodisiacs are required to improve male sexual function under stressful conditions. Due to the effects of oxidative stress and dopamine on male sexual function, we hypothesized that Moringa oleifera leaves might improve male sexual dysfunction induced by stress. Therefore, the effects on various factors playing important roles in male sexual behavior, such as antioxidant effects, the suppression of monoamine and phosphodiesterase type 5 (PDE-5) activities, serum testosterone and corticosterone levels, and histomorphological changes in the testes, of a hydroethanolic extract of M. oleifera leaves were investigated. Various doses of extract including 10, 50, and 250 mg/kg body weight (BW) were given orally to male Wistar rats before exposure to 12 h-immobilization stress for 7 d. The results demonstrated that the extract showed both antioxidant and monoamine oxidase type B (MAO-B) suppression activities. At 7 d of treatment, the low dose of extract improved sexual performance in stress-exposed rats by decreasing intromission latency and increasing intromission frequency. It also suppressed PDE-5 activity, decreased serum corticosterone level, but increased serum testosterone, numbers of interstitial cells of Leydig and spermatozoa. The increased numbers of interstitial cells of Leydig and spermatozoa might have been due to the antioxidant effect of the extract. The increased sexual performance during the intromission phase might have been due to the suppression of MAO-B and PDE-5 activities and increased testosterone. Therefore, M. oleifera is a potential aphrodisiac, but further research concerning the precise underlying mechanisms is still needed. PMID:25743119

  18. Overfeeding reduces insulin sensitivity and increases oxidative stress, without altering markers of mitochondrial content and function in humans.

    Directory of Open Access Journals (Sweden)

    Dorit Samocha-Bonet

    Full Text Available BACKGROUND: Mitochondrial dysfunction and increased oxidative stress are associated with obesity and type 2 diabetes. High fat feeding induces insulin resistance and increases skeletal muscle oxidative stress in rodents, but there is controversy as to whether skeletal muscle mitochondrial biogenesis and function is altered. METHODOLOGY AND PRINCIPAL FINDINGS: Forty (37 ± 2 y non-obese (25.6 ± 0.6 kg/m(2 sedentary men (n = 20 and women (n = 20 were overfed (+1040 ± 100 kcal/day, 46 ± 1% of energy from fat for 28 days. Hyperinsulinemic-euglycemic clamps were performed at baseline and day 28 of overfeeding and skeletal muscle biopsies taken at baseline, day 3 and day 28 of overfeeding in a sub cohort of 26 individuals (13 men and 13 women that consented to having all 3 biopsies performed. Weight increased on average in the whole cohort by 0.6 ± 0.1 and 2.7 ± 0.3 kg at days 3 and 28, respectively (P<0.0001, without a significant difference in the response between men and women (P = 0.4. Glucose infusion rate during the hyperinsulinemic-euglycemic clamp decreased from 54.8 ± 2.8 at baseline to 50.3 ± 2.5 µmol/min/kg FFM at day 28 of overfeeding (P = 0.03 without a significant difference between men and women (P = 0.4. Skeletal muscle protein carbonyls and urinary F2-isoprostanes increased with overfeeding (P<0.05. Protein levels of muscle peroxisome proliferator-activated receptor gamma coactivator-1α (PGC1α and subunits from complex I, II and V of the electron transport chain were increased at day 3 (all P<0.05 and returned to basal levels at day 28. No changes were detected in muscle citrate synthase activity or ex vivo CO(2 production at either time point. CONCLUSIONS: Peripheral insulin resistance was induced by overfeeding, without reducing any of the markers of mitochondrial content that were examined. Oxidative stress was however increased, and may have contributed to the reduction in insulin sensitivity observed.

  19. Chronic social stress during adolescence in mice alters fat distribution in late life: prevention by antidepressant treatment.

    Science.gov (United States)

    Schmidt, M V; Czisch, M; Sterlemann, V; Reinel, C; Sämann, P; Müller, M B

    2009-01-01

    Obesity and visceral fat accumulation are key features of the metabolic syndrome that represents one of the main health problems in western societies due to its neurovascular and cardiovascular complications. Epidemiological studies have identified chronic stress exposure as an important risk factor for the development of obesity and metabolic syndrome, but also psychiatric diseases, especially affective disorders. However, it is still unclear if chronic stress has merely transient or potentially lasting effects on body composition. Here, we investigated the effects of chronic social stress during the adolescent period on body fat composition in mice one year after the cessation of the stressor. We found that stress exposure during the adolescent period decreases subcutaneous fat content, without change in visceral fat, and consequently increases the visceral fat/subcutaneous fat ratio in adulthood. Further, we demonstrated that treatment with a selective serotonin reuptake inhibitor (paroxetine) during stress exposure prevented later effects on body fat distribution. These results from a recently validated chronic stress paradigm in mice provide evidence that stressful experiences during adolescence can alter body fat distribution in adulthood, thereby possibly contributing to an increased risk for metabolic diseases. Antidepressant treatment disrupted this effect underlining the link between the stress hormone system, metabolic homeostasis and affective disorders. PMID:18951248

  20. Prenatal SSRI alters the hormonal and behavioral responses to stress in female mice: Possible role for glucocorticoid resistance.

    Science.gov (United States)

    Avitsur, Ronit; Grinshpahet, Rachel; Goren, Naama; Weinstein, Ido; Kirshenboim, Or; Chlebowski, Noa

    2016-08-01

    Life time prevalence of major depression disorder (MDD) is higher in women compared to men especially during the period surrounding childbirth. Women suffering from MDD during pregnancy use antidepressant medications, particularly Selective Serotonin Reuptake Inhibitors (SSRI). These drugs readily cross the placental barrier and impact the developing fetal brain. The present study assessed the effects of prenatal exposure to fluoxetine (FLX), an SSRI antidepressant drug, on corticosterone and behavioral responses to stress in female mice. In young females, prenatal FLX significantly elevated corticosterone response to continuous stress. In adults, prenatal FLX augmented corticosterone response to acute stress and suppressed the response to continuous stress. Additionally, prenatal FLX significantly augmented stress-induced increase in locomotion and reduced anxiety- and depressive-like behaviors in adult, but not young mice. The dexamethasone suppression test revealed that prenatal FLX induced a state of glucocorticoid resistance in adult females, indicating that the negative feedback control of the hypothalamic-pituitary-adrenal axis response to stress was disrupted. These findings provide the first indication of altered hormonal and behavioral responses to continuous stress and suggest a role for the development of glucocorticoid resistance in these effects. According to these findings, prenatal environment may have implications for stress sensitivity and responsiveness to life challenges. Furthermore, this study may assist in understanding the limitations and precautions that should be taken in the use of SSRIs during pregnancy. PMID:27283378

  1. Partial genetic deletion of neuregulin 1 and adolescent stress interact to alter NMDA receptor binding in the medial prefrontal cortex

    Directory of Open Access Journals (Sweden)

    Tariq Waseem Chohan

    2014-09-01

    Full Text Available Schizophrenia is thought to arise due to a complex interaction between genetic and environmental factors during early neurodevelopment. We have recently shown that partial genetic deletion of the schizophrenia susceptibility gene neuregulin 1 (Nrg1 and adolescent stress interact to disturb sensorimotor gating, neuroendocrine activity and dendritic morphology in mice. Both stress and Nrg1 may have converging effects upon N-methyl-D-aspartate receptors (NMDARs which are implicated in the pathogenesis of schizophrenia, sensorimotor gating and dendritic spine plasticity. Using an identical repeated restraint stress paradigm to our previous study, here we determined NMDAR binding across various brain regions in adolescent Nrg1 heterozygous (HET and wild-type (WT mice using [3H] MK-801 autoradiography. Repeated restraint stress increased NMDAR binding in the ventral part of the lateral septum (LSV and the dentate gyrus (DG of the hippocampus irrespective of genotype. Partial genetic deletion of Nrg1 interacted with adolescent stress to promote an altered pattern of NMDAR binding in the infralimbic (IL subregion of the medial prefrontal cortex. In the IL, whilst stress tended to increase NMDAR binding in WT mice, it decreased binding in Nrg1 HET mice. However in the DG, stress selectively increased the expression of NMDAR binding in Nrg1 HET mice but not WT mice. These results demonstrate a Nrg1-stress interaction during adolescence on NMDAR binding in the medial prefrontal cortex.

  2. High aggression in rats is associated with elevated stress, anxiety-like behavior, and altered catecholamine content in the brain

    Science.gov (United States)

    Patki, Gaurav; Atrooz, Fatin; Alkadhi, Isam; Solanki, Naimesh; Salim, Samina

    2015-01-01

    The social defeat paradigm involves aggressive encounters between Long-Evans (LE) (resident) and Sprague-Dawley (SD) (intruder) rats. Successful application of chronic social defeat stress in SD rats is dependent upon selection of highly aggressive LE rats. Half of the LE rats screened for aggression did not meet the criterion for aggression (LE rats performing a defeat, characterized by the intruder surrendering or acquiring a supine position for at least 3 sec). The observation of the differences in the level of aggression between age and weight matched LE rats was quite compelling which led us to the present study. Herein, we measured behavioral differences between aggressor and non-aggressor LE rats. We analyzed their anxiety-like behavior using open-field and elevated plus maze tests. We also measured aggression/violence-like behavior using two tests. In one, time taken to defeat the intruder SD rat was recorded. In the second test, time taken to attack a novel object was compared between the two groups. We observed a significant increase in anxiety-like behavior in aggressor rats when compared to the non-aggressive group. Furthermore, time taken to defeat the intruder rat and to attack a novel object was significantly lower in aggressive LE rats. Biochemical data suggests that heightened anxiety-like behavior and aggression is associated with increased plasma levels of corticosterones and elevated oxidative stress. Significant alterations in dopamine (DA), norepinephrine (NE) and epinephrine (EPI) were observed within the hippocampus, amygdala and the prefrontal cortex, suggesting potential involvement of dopaminergic and noradrenergic systems in regulation of aggressive behaviors. PMID:25450144

  3. Carbonated soft drinks induce oxidative stress and alter the expression of certain genes in the brains of Wistar rats.

    Science.gov (United States)

    El-Terras, Adel; Soliman, Mohamed Mohamed; Alkhedaide, Adel; Attia, Hossam Fouad; Alharthy, Abdullah; Banaja, Abdel Elah

    2016-04-01

    In Saudi Arabia, the consumption of carbonated soft drinks is common and often occurs with each meal. Carbonated soft drink consumption has been shown to exhibit effects on the liver, kidney and bone. However, the effects of these soft drinks on brain activity have not been widely examined, particularly at the gene level. Therefore, the current study was conducted with the aim of evaluating the effects of chronic carbonated soft drink consumption on oxidative stress, brain gene biomarkers associated with aggression and brain histology. In total, 40 male Wistar rats were divided into four groups: Group 1 served as a control and was provided access to food and water ad libitum; and groups 2‑4 were given free access to food and carbonated soft drinks only (Cola for group 2, Pepsi for group 3 and 7‑UP for group 4). Animals were maintained on these diets for 3 consecutive months. Upon completion of the experimental period, animals were sacrificed and serological and histopathological analyses were performed on blood and tissues samples. Reverse transcription‑polymerase chain reaction was used to analyze alterations in gene expression levels. Results revealed that carbonated soft drinks increased the serum levels of malondialdehyde (MDA). Carbonated soft drinks were also observed to downregulate the expression of antioxidants glutathione reductase (GR), catalase and glutathione peroxidase (GPx) in the brain when compared with that in the control rats. Rats administered carbonated soft drinks also exhibited decreased monoamine oxidase A (MAO‑A) and acetylcholine esterase (AChE) serum and mRNA levels in the brain. In addition, soft drink consumption upregulated mRNA expression of dopamine D2 receptor (DD2R), while 5-hydroxytryptamine transporter (5‑HTT) expression was decreased. However, following histological examination, all rats had a normal brain structure. The results of this study demonstrated that that carbonated soft drinks induced oxidative stress and

  4. Prenatal stress alters diazepam withdrawal syndrome and 5HT1A receptor expression in the raphe nuclei of adult rats.

    Science.gov (United States)

    Lakehayli, S; Said, N; El Khachibi, M; El Ouahli, M; Nadifi, S; Hakkou, F; Tazi, A

    2016-08-25

    Early-life events have long-term effects on brain structures and cause behavioral alterations that persist into adulthood. The present experiments were designed to investigate the effects of prenatal stress on diazepam-induced withdrawal syndrome and serotonin-1A (5HT1A) receptor expression in the raphe nuclei of adult offspring. The results of the present study reveal that maternal exposure to chronic footshock stress increased the anxiety-like behavior in the prenatally stressed (PS) animals withdrawn from chronic diazepam (2.5mg/kg/day i.p for 1week). Moreover, prenatal stress induced a down-regulation of 5HT1A mRNA in the raphe nuclei of adult offspring. To our knowledge, this study is the first to demonstrate that maternal exposure to chronic footshock stress enhances diazepam withdrawal symptoms and alters 5HT1A receptor gene expression in the raphe nuclei of adult offspring. Thus, more studies are needed to clarify the mechanisms underlying the decrease of 5HT1A receptors expression in the raphe nuclei of PS rats. PMID:27235743

  5. Role for MMP-9 in stress-induced downregulation of nectin-3 in hippocampal CA1 and associated behavioural alterations.

    Science.gov (United States)

    van der Kooij, Michael A; Fantin, Martina; Rejmak, Emilia; Grosse, Jocelyn; Zanoletti, Olivia; Fournier, Celine; Ganguly, Krishnendu; Kalita, Katarzyna; Kaczmarek, Leszek; Sandi, Carmen

    2014-01-01

    Chronic stress is a risk factor for the development of psychopathologies characterized by cognitive dysfunction and deregulated social behaviours. Emerging evidence suggests a role for cell adhesion molecules, including nectin-3, in the mechanisms that underlie the behavioural effects of stress. We tested the hypothesis that proteolytic processing of nectins by matrix metalloproteinases (MMPs), an enzyme family that degrades numerous substrates, including cell adhesion molecules, is involved in hippocampal effects induced by chronic restraint stress. A reduction in nectin-3 in the perisynaptic CA1, but not in the CA3, compartment is observed following chronic stress and is implicated in the effects of stress in social exploration, social recognition and a CA1-dependent cognitive task. Increased MMP-9-related gelatinase activity, involving N-methyl-D-aspartate receptor, is specifically found in the CA1 and involved in nectin-3 cleavage and chronic stress-induced social and cognitive alterations. Thus, MMP-9 proteolytic processing emerges as an important mediator of stress effects in brain function and behaviour. PMID:25232752

  6. Alterations in neuronal morphology in infralimbic cortex predict resistance to fear extinction following acute stress.

    Science.gov (United States)

    Moench, Kelly M; Maroun, Mouna; Kavushansky, Alexandra; Wellman, Cara

    2016-06-01

    Dysfunction in corticolimbic circuits that mediate the extinction of learned fear responses is thought to underlie the perseveration of fear in stress-related psychopathologies, including post-traumatic stress disorder. Chronic stress produces dendritic hypertrophy in basolateral amygdala (BLA) and dendritic hypotrophy in medial prefrontal cortex, whereas acute stress leads to hypotrophy in both BLA and prelimbic cortex. Additionally, both chronic and acute stress impair extinction retrieval. Here, we examined the effects of a single elevated platform stress on extinction learning and dendritic morphology in infralimbic cortex, a region considered to be critical for extinction. Acute stress produced resistance to extinction, as well as dendritic retraction in infralimbic cortex. Spine density on apical and basilar terminal branches was unaffected by stress. However, animals that underwent conditioning and extinction had decreased spine density on apical terminal branches. Thus, whereas dendritic morphology in infralimbic cortex appears to be particularly sensitive to stress, changes in spines may more sensitively reflect learning. Further, in stressed rats that underwent conditioning and extinction, the level of extinction learning was correlated with spine densities, in that rats with poorer extinction retrieval had more immature spines and fewer thin spines than rats with better extinction retrieval, suggesting that stress may have impaired learning-related spine plasticity. These results may have implications for understanding the role of medial prefrontal cortex in learning deficits associated with stress-related pathologies. PMID:26844245

  7. Overcrowding-mediated stress alters cell proliferation in key neuroendocrine areas during larval development in Rhinella arenarum.

    Science.gov (United States)

    Distler, Mijal J; Jungblut, Lucas D; Ceballos, Nora R; Paz, Dante A; Pozzi, Andrea G

    2016-02-01

    Exposure to adverse environmental conditions can elicit a stress response, which results in an increase in endogenous corticosterone levels. In early life stages, it has been thoroughly demonstrated that amphibian larval growth and development is altered as a consequence of chronic stress by interfering with the metamorphic process, however, the underlying mechanisms involved have only been partially disentangled. We examined the effect of intraspecific competition on corticosterone levels during larval development of the toad Rhinella arenarum and its ultimate effects on cell proliferation in particular brain areas as well as the pituitary gland. While overcrowding altered the number of proliferating cells in the pituitary gland, hypothalamus, and third ventricle of the brain, no differences were observed in areas which are less associated with neuroendocrine processes, such as the first ventricle of the brain. Apoptosis was increased in hypothalamic regions but not in the pituitary. With regards to pituitary cell populations, thyrotrophs but not somatoatrophs and corticotrophs showed a decrease in the cell number in overcrowded larvae. Our study shows that alterations in growth and development, produced by stress, results from an imbalance in the neuroendocrine systems implicated in orchestrating the timing of metamorphosis. J. Exp. Zool. 9999A:XX-XX, 2016. © 2016 Wiley Periodicals, Inc. PMID:26817921

  8. Acute stress alters amygdala microRNA miR-135a and miR-124 expression: inferences for corticosteroid dependent stress response.

    Directory of Open Access Journals (Sweden)

    Cecilia Mannironi

    Full Text Available The amygdala is a brain structure considered a key node for the regulation of neuroendocrine stress response. Stress-induced response in amygdala is accomplished through neurotransmitter activation and an alteration of gene expression. MicroRNAs (miRNAs are important regulators of gene expression in the nervous system and are very well suited effectors of stress response for their ability to reversibly silence specific mRNAs. In order to study how acute stress affects miRNAs expression in amygdala we analyzed the miRNA profile after two hours of mouse restraint, by microarray analysis and reverse transcription real time PCR. We found that miR-135a and miR-124 were negatively regulated. Among in silico predicted targets we identified the mineralocorticoid receptor (MR as a target of both miR-135a and miR-124. Luciferase experiments and endogenous protein expression analysis upon miRNA upregulation and inhibition allowed us to demonstrate that mir-135a and mir-124 are able to negatively affect the expression of the MR. The increased levels of the amygdala MR protein after two hours of restraint, that we analyzed by western blot, negatively correlate with miR-135a and miR-124 expression. These findings point to a role of miR-135a and miR-124 in acute stress as regulators of the MR, an important effector of early stress response.

  9. Edge Stabilized Ribbon (ESR); Stress, Dislocation Density and Electronic Performance

    Science.gov (United States)

    Sachs, E. M.

    1984-01-01

    The edge stabilized ribbon (ESR) silicon ribbon was grown in widths of 1, 2.2 and 4.0 inches at speeds ranging from .6 to 7 in/min, which result in ribbon thicknesses of 5 to 400 microns. One of the primary problems remaining in ESR growth is that of thermally induced mechanical stresses. This problem is manifested as ribbon with a high degree of residual stress or as ribbon with buckled ribbon. Thermal stresses result in a high dislocation density in the grown material, resulting in compromised electronic performance. Improvements in ribbon flatness were accomplished by modification of the ribbon cooling profile. Ribbon flatness and other experimental observations of ESR ribbon are discussed. Laser scanner measurements show a good correlation between diffusion length and dislocation density which indicates that the high dislocation densities are the primary cause of the poor current performance of ESR materials. Dislocation densities were reduced and improved electronic performance resulted. Laser scanner data on new and old material are presented.

  10. Alterations in the Vaginal Microbiome by Maternal Stress Are Associated With Metabolic Reprogramming of the Offspring Gut and Brain.

    Science.gov (United States)

    Jašarević, Eldin; Howerton, Christopher L; Howard, Christopher D; Bale, Tracy L

    2015-09-01

    The neonate is exposed to the maternal vaginal microbiota during parturition, providing the primary source for normal gut colonization, host immune maturation, and metabolism. These early interactions between the host and microbiota occur during a critical window of neurodevelopment, suggesting early life as an important period of cross talk between the developing gut and brain. Because perturbations in the prenatal environment such as maternal stress increase neurodevelopmental disease risk, disruptions to the vaginal ecosystem could be a contributing factor in significant and long-term consequences for the offspring. Therefore, to examine the hypothesis that changes in the vaginal microbiome are associated with effects on the offspring gut microbiota and on the developing brain, we used genomic, proteomic and metabolomic technologies to examine outcomes in our mouse model of early prenatal stress. Multivariate modeling identified broad proteomic changes to the maternal vaginal environment that influence offspring microbiota composition and metabolic processes essential for normal neurodevelopment. Maternal stress altered proteins related to vaginal immunity and abundance of Lactobacillus, the prominent taxa in the maternal vagina. Loss of maternal vaginal Lactobacillus resulted in decreased transmission of this bacterium to offspring. Further, altered microbiota composition in the neonate gut corresponded with changes in metabolite profiles involved in energy balance, and with region- and sex-specific disruptions of amino acid profiles in the developing brain. Taken together, these results identify the vaginal microbiota as a novel factor by which maternal stress may contribute to reprogramming of the developing brain that may predispose individuals to neurodevelopmental disorders. PMID:26079804

  11. Algorithms Based on CWT and Classifiers to Control Cardiac Alterations and Stress Using an ECG and a SCR

    Directory of Open Access Journals (Sweden)

    Amaia Méndez Zorrilla

    2013-05-01

    Full Text Available This paper presents the results of using a commercial pulsimeter as an electrocardiogram (ECG for wireless detection of cardiac alterations and stress levels for home control. For these purposes, signal processing techniques (Continuous Wavelet Transform (CWT and J48 have been used, respectively. The designed algorithm analyses the ECG signal and is able to detect the heart rate (99.42%, arrhythmia (93.48% and extrasystoles (99.29%. The detection of stress level is complemented with Skin Conductance Response (SCR, whose success is 94.02%. The heart rate variability does not show added value to the stress detection in this case. With this pulsimeter, it is possible to prevent and detect anomalies for a non-intrusive way associated to a telemedicine system. It is also possible to use it during physical activity due to the fact the CWT minimizes the motion artifacts.

  12. Heat stress causes alterations in the cell-wall polymers and anatomy of coffee leaves (Coffea arabica L.).

    Science.gov (United States)

    Lima, Rogério Barbosa; dos Santos, Tiago Benedito; Vieira, Luiz Gonzaga Esteves; Ferrarese, Maria de Lourdes Lúcio; Ferrarese-Filho, Osvaldo; Donatti, Lucélia; Boeger, Maria Regina Torres; Petkowicz, Carmen Lúcia de Oliveira

    2013-03-01

    Coffee plants were subjected to heat stress (37 °C) and compared with control plants (24 °C). Cell wall polysaccharides were extracted using water (W), EDTA (E) and 4M NaOH (H30 and H70). In addition, monolignols were analyzed, and the leaves were observed by microscopy. Plants under heat stress accumulated higher contents of arabinose and galactose in fraction W. Xylose contents were observed to decrease in H30 fractions after the heat stress, whereas galactose and uronic acid increased. H70 fractions from plants exposed to heat stress showed increased xylose contents, whereas the contents of arabinose and glucose decreased. Differences in the molar-mass profiles of polysaccharides were also observed. The primary monolignol contents increased after the heat stress. Structural alterations in palisade cells and ultrastructural damage in chloroplasts were also observed. Our results demonstrate that the chemical profile of coffee cell-wall polymers and structural cell anatomy change under heat stress. PMID:23465912

  13. Stress-Induced Alterations in Coagulation : Assessment of a New Hemoconcentration Correction Technique

    OpenAIRE

    Anthony W. Austin; Wirtz, Petra H; Stephen M. Patterson; Stutz, Monika; von Känel, Roland

    2012-01-01

    For the examination of psychological stress effects on coagulation, the Dill and Costill correction (DCC) for hemoconcentration effects has been used to adjust for stress-induced plasma volume changes. Although the correction is appropriate for adjusting concentrations of various large blood constituents, it may be inappropriate for time-dependent or functional coagulation assays. Two new plasma reconstitution techniques for correcting hemoconcentration effects on stress-induced changes in co...

  14. Maternal postnatal depression predicts altered offspring biological stress reactivity in adulthood

    OpenAIRE

    Barry, Tom J.; Murray, Lynne; Fearon, R. M. Pasco; Moutsiana, Christina; Cooper, Peter; Goodyer, Ian M.; Herbert, Joe; Halligan, Sarah L.

    2015-01-01

    Summary The offspring of depressed parents have been found to show elevated basal levels of the stress hormone cortisol. Whether heightened cortisol stress reactivity is also present in this group has yet to be clearly demonstrated. We tested whether postnatal maternal depression predicts subsequent increases in offspring biological sensitivity to social stress, as indexed by elevated cortisol reactivity. Participants (mean age 22.4-years) derived from a 22-year prospective longitudinal study...

  15. Functional Task Test: 1. Sensorimotor changes Associated with Postflight Alterations in Astronaut Functional Task Performance

    Science.gov (United States)

    Bloomberg, J. J.; Arzeno, N. H.; Buxton, R. E.; Feiveson, A. H.; Kofman, I. S.; Lee, S. M. C.; Miller, C. A.; Mulavara, A. P.; Platts, S. H.; Peters, B. T.; Phillips, T.; Ploutz-Snyder, L. L.; Reschke, M. F.; Ryder, J. W.; Spiering, B. A.; Stenger, M. B.; Taylor, L. C.; Wickwire, P. J.; Wood, S. J.

    2011-01-01

    Space flight is known to cause alterations in multiple physiological systems including changes in sensorimotor, cardiovascular, and neuromuscular systems. These changes may affect a crewmember s ability to perform critical mission tasks immediately after landing on a planetary surface. The overall goal of this project is to determine the effects of space flight on functional tests that are representative of high priority exploration mission tasks and to identify the key underlying physiological factors that contribute to decrements in performance. This presentation will focus on the sensorimotor contributions to postflight functional performance.

  16. Relationship between mental toughness, stress appraisal, and innovation performance of R&D personnel

    OpenAIRE

    Feng Jin

    2016-01-01

    Four hundred and two R&D personnel were surveyed through questionnaires to study the relationship between mental toughness, stress appraisal (including experience of stress and stress control), and innovation performance. The findings reveal a significant negative correlation between mental toughness and stress experience and a significant positive correlation between mental toughness and both stress control and innovation performance. Furthermore, although the experience of stress was negati...

  17. Functional Immune Alterations, Latent Herpesvirus Reactivation, Physiological Stress and Clinical Incidence Onboard the International Space Station

    Science.gov (United States)

    Crucian, Brian; Kunz, Hawley; Mehta, Satish; Stowe, Ray; Ploutz-Snyder, Robert; Quiriarte, Heather; Chouker, Alexander; Pierson, Duane

    2016-01-01

    This study (OpNom 'Functional Immune') will be a comprehensive immunity Flight Definition investigation that will use longitudinal repeated measures to assess various aspects of immunity and viral reactivation during long-duration spaceflight. This proposal builds on the successful sampling architecture of the former Integrated Immune flight study, which for the first time returned ambient, live blood samples from space to allow functional assays. Blood (ambient, live) and saliva samples will be collected before, during, and following spaceflight. Previously uninvestigated live cell assays will be performed to assess cellular function during spaceflight. Specialized preservatives will be utilized to assess comprehensive immunophenotype, gene expression and proteomics. Measures of inflammation, stress, antimicrobial activity, etc. will be assessed in blood, saliva, and/or urine. The reactivation of a panel of herpesviruses will be assessed both during flight, and post-flight until shedding resolves. Array technology will be utilized to allow maximal information to be derived from minimal in-flight samples. This study will be a hybrid of NASA internal scientists and researchers external to NASA. The NASA 'Core' science package and implementation strategy was selected and approved in 2014. Via NRA, the solicitation for external participation, with science directed to comply with the parent study sampling architecture, is in progress

  18. STRESS; THE VULNERABILITY AND ASSOCIATION WITH DRIVING PERFORMANCE

    Directory of Open Access Journals (Sweden)

    B. M.T. Shamsul

    2014-01-01

    Full Text Available Several factors may contribute to occurrence of road accidents which are human factors, vehicle factor, road factor and environmental factor. There has been recent evidence of a relationship between road accidents and emotional distress as well as fatigue. Monotonous and complex road environments are the road factor that relates to the internal factor within driver. The overall aim of this study was to compare driving stress, fatigue and driving error between complex and monotonous driving. This experimental study was carried out to measure the stress level, fatigue status and driving performance among hundred male drivers (20-59 years with driving experience more than one year. Cortisol concentration from respondents’ saliva was obtained to measure the stress level due to the driving test. Cortisols were measured using Salimetrics cortisol Enzyme Immunoassay kit (ELISA. Fatigue status was measured by using EEG test to the respondents while conducted the simulator driving test. Driving performance was measured based on the recorded data of Running-of-the Roads (RORI and Large Speed Variation (LSV index from the simulator system. This study found that there was a significant difference (p<0.05 between cortisol levels, EEG value and driving errors of monotonous and complex driving. Salivary cortisol level was found higher during monotonous driving compared to complex driving. Theta wave which indicates sleepy and fatigue condition was found higher on monotonous driving compared to other brainwaves which is alpha and beta state. RORI and LSV index was higher recorded during driving in complex road environments. The main implications of this study for road safety shows that monotonous driving had significantly induced driving stress and fatigue while complex driving lead to higher driving errors. Human factors and road factors could possibly put drivers in a higher risk to be involved in road accidents.

  19. Prenatal Transportation Stress Alters Temperament and Serum Cortisol Concentrations in Suckling Brahman Calves

    Science.gov (United States)

    This experiment examined the relationship between prenatal stress and subsequent calf temperament through weaning. The prenatal stressor utilized was repeated transportation of pregnant Brahman cows for 2 hours at 60, 80, 100, 120, and 140 days of gestation. Prenatally stressed calves (n = 41) were ...

  20. The impact of stress on motor performance in skilled musicians suffering from focal dystonia: Physiological and psychological characteristics.

    Science.gov (United States)

    Ioannou, Christos I; Furuya, Shinichi; Altenmüller, Eckart

    2016-05-01

    Recent investigations have suggested that stress can modulate motor function. However, the impact of stress on motor performance of musicians suffering from focal dystonia (FDM) remains unknown. The current study assessed motor performance in 20 FDM patients and 16 healthy musicians (HM) before and under stress. Stress was manipulated using the Trier Social Stress Test (TSST). Motor performance was evaluated based on analysis of electromyographic (EMG) activity and temporal variability, while electrocardiography (ECG) and the level of free cortisol were used to test for objective alterations of the hypothalamic-pituitary-adrenal (HPA) axis. Finally, the psychological profiles of both groups were analyzed using three psycho-diagnostic standardized questionnaires. Results showed that patients' motor impairments did not change under acute stressful conditions. However, an increase in muscular co-contractions was observed, reflecting a physiological muscular response under stressful conditions. Psycho-diagnostic analysis revealed higher levels of psychological traits related to elevated anxiety, stress and perfectionism in 40% of the patients. Although the motor outcome between those patients and those with an opposing psychological profile did not differ, patients characterized by stressful and perfectionistic personalities had, on average, developed dystonia about ten years earlier than the rest of the patients. The current study suggests that acute stress conditions may not have any direct impact on fine motor control of FDM patients. However psychological traits associated with increased stress, anxiety and perfectionism may have a long-lasting effect on the motor function of affected musicians, by promoting the acceleration or even the triggering of dystonia. PMID:27033741

  1. Anatomical Alteration in Response to Irrigation and Water Stress in Some Legume Crops

    OpenAIRE

    Abdel, C. G.; Al-Rawi, Iqbal Murad Thahir

    2011-01-01

    Anatomical alteration of leaf tissues components were investigated in regards to adequate and inadequate watering in Mungbean, Vetch and three Lentil cultivars namely Baraka, Adlib and Nineveh. The possibility of mitigating the alteration of these adversities by the aid of GA3 was also investigated. Lentil plants irrigated by 50% level appeared to be the most effective treatment. This treatment manifested the best results as it exceeded that of 75% level in terms of cuticle thickness (69.3%),...

  2. Systemic alterations in the metabolome of diabetic NOD mice delineate increased oxidative stress accompanied by reduced inflammation and hypertriglyceremia.

    Science.gov (United States)

    Fahrmann, Johannes; Grapov, Dmitry; Yang, Jun; Hammock, Bruce; Fiehn, Oliver; Bell, Graeme I; Hara, Manami

    2015-06-01

    Nonobese diabetic (NOD) mice are a commonly used model of type 1 diabetes (T1D). However, not all animals will develop overt diabetes despite undergoing similar autoimmune insult. In this study, a comprehensive metabolomic approach, consisting of gas chromatography time-of-flight (GC-TOF) mass spectrometry (MS), ultra-high-performance liquid chromatography-accurate mass quadruple time-of-flight (UHPLC-qTOF) MS and targeted UHPLC-tandem mass spectrometry-based methodologies, was used to capture metabolic alterations in the metabolome and lipidome of plasma from NOD mice progressing or not progressing to T1D. Using this multi-platform approach, we identified >1,000 circulating lipids and metabolites in male and female progressor and nonprogressor animals (n = 71). Statistical and multivariate analyses were used to identify age- and sex-independent metabolic markers, which best differentiated metabolic profiles of progressors and nonprogressors. Key T1D-associated perturbations were related with 1) increases in oxidation products glucono-δ-lactone and galactonic acid and reductions in cysteine, methionine and threonic acid, suggesting increased oxidative stress; 2) reductions in circulating polyunsaturated fatty acids and lipid signaling mediators, most notably arachidonic acid (AA) and AA-derived eicosanoids, implying impaired states of systemic inflammation; 3) elevations in circulating triacylglyercides reflective of hypertriglyceridemia; and 4) reductions in major structural lipids, most notably lysophosphatidylcholines and phosphatidylcholines. Taken together, our results highlight the systemic perturbations that accompany a loss of glycemic control and development of overt T1D. PMID:25852003

  3. Cannabinoids reverse the effects of early stress on neurocognitive performance in adulthood.

    Science.gov (United States)

    Alteba, Shirley; Korem, Nachshon; Akirav, Irit

    2016-07-01

    Early life stress (ES) significantly increases predisposition to psychopathologies. Cannabinoids may cause cognitive deficits and exacerbate the effects of ES. Nevertheless, the endocannabinoid system has been suggested as a therapeutic target for the treatment of stress- and anxiety-related disorders. Here we examined whether cannabinoids administered during "late adolescence" (extensive cannabis use in humans at the ages 18-25) could reverse the long-term adverse effects of ES on neurocognitive function in adulthood. Male and female rats were exposed to ES during post-natal days (P) 7-14, injected with the cannabinoid CB1/2 receptor agonist WIN55,212-2 (WIN; 1.2 mg/kg, i.p.) for 2 wk during late adolescence (P45-60) and tested in adulthood (P90) for working memory, anxiety, and alterations in CB1 receptors (CB1r), and glucocorticoid receptors (GRs) in the stress circuit [hippocampus, prefrontal cortex (PFC), and basolateral amygdala (BLA)]. ES males and females exhibited impaired performance in short-term memory in adulthood in the spatial location and social recognition tasks; males were also impaired in the novel object recognition task. WIN administered during late adolescence prevented these stress-induced impairments and reduced anxiety levels. WIN normalized the ES-induced up-regulation in PFC-GRs and CA1-CB1r in females. In males, WIN normalized the ES-induced up-regulation in PFC-GR and down-regulation in BLA-CB1r. There is a crucial role of the endocannabinoid system in the effects of early life stress on behavior at adulthood. Differences in recognition memory and in the expression of GRs and CB1r in the fear circuit suggest sex differences in the mechanism underlying coping with stress. PMID:27317195

  4. 46 CFR 54.30-10 - Method of performing mechanical stress relief.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Method of performing mechanical stress relief. 54.30-10... PRESSURE VESSELS Mechanical Stress Relief § 54.30-10 Method of performing mechanical stress relief. (a) The mechanical stress relief shall be carried out in accordance with the following stipulations using water...

  5. Change of the chemical barrier performance of cement materials altered by hydrothermal reaction

    International Nuclear Information System (INIS)

    due to the decomposition of ettringite which sorbs anions. The distribution coefficient for BFS with distilled sorbs anions, although the ettringite has decomposed. Monosulphate might be a more effective sorbent for selenite than ettringite. These results show that the hydrothermal alteration of cement mineral phases in a disposal environment may cause changes which could give rise to either an improvement or a deterioration in the sorption of radionuclides onto cement materials. More investigation will be required by performing sorption tests with TRU elements, and a modeling study is also required. (author)

  6. Chronic Physical Stress Does Not Interact with Epstein-Barr Virus (EBV)-Encoded Dutpase to Alter the Sickness Response

    Science.gov (United States)

    Weil, Zachary M.; Abi Salloum, Bachir; Ariza, Maria Eugenia; Williams, Marshall; Reader, Brenda; Glaser, Ronald; Sheridan, John; Nelson, Randy J.

    2016-01-01

    Most adult humans have been infected with Epstein-Barr virus (EBV), which is thought to contribute to the development of chronic fatigue syndrome. Stress is known to influence the immune system and can exacerbate the sickness response. Although a role for psychological stress in the sickness response, particularly in combination with EBV-encoded deoxyuridine triphosphate nucleotidohydrolase (dUTPase) has been established, and the role of physical stressors in these interactions remains unspecified. In this study, we seek to determine the interaction of chronic physical (swim) stress and EBV-encoded dUTPase injection. We hypothesize that a chronic physical stressor will exacerbate the sickness response following EBV-encoded dUTPase injection. To test this hypothesis mice receive daily injections of EBV-encoded dUTPase or vehicle and are subjected to 15 min of swim stress each day for 14 days or left unmanipulated. On the final evening of injections mice undergo behavioral testing. EBV-encoded dUTPase injection alone produces some sickness behaviors. The physical swimming stress does not alter the sickness response.

  7. Cadmium stress alters the redox reaction and hormone balance in oilseed rape (Brassica napus L.) leaves.

    Science.gov (United States)

    Yan, Hui; Filardo, Fiona; Hu, Xiaotao; Zhao, Xiaomin; Fu, DongHui

    2016-02-01

    In order to understand the physiological response of oilseed rape (Brassica napus L.) leaves to cadmium (Cd) stress and exploit the physiological mechanisms involved in Cd tolerance, macro-mineral and chlorophyll concentrations, reactive oxygen species (ROS) accumulation, activities of enzymatic antioxidants, nonenzymatic compounds metabolism, endogenous hormonal changes, and balance in leaves of oilseed rape exposed to 0, 100, or 200 μM CdSO4 were investigated. The results showed that under Cd exposure, Cd concentrations in the leaves continually increased while macro-minerals and chlorophyll concentrations decreased significantly. Meanwhile, with increased Cd stress, superoxide anion (O2(• -)) production rate and hydrogen peroxide (H2O2) concentrations in the leaves increased significantly, which caused malondialdehyde (MDA) accumulation and oxidative stress. For scavenging excess accumulated ROS and alleviating oxidative injury in the leaves, the activity of enzymatic antioxidants, such as superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), was increased significantly at certain stress levels. However, with increased Cd stress, the antioxidant enzyme activities all showed a trend towards reduction. The nonenzymatic antioxidative compounds, such as proline and total soluble sugars, accumulated continuously with increased Cd stress to play a long-term role in scavenging ROS. In addition, ABA levels also increased continuously with Cd stress while ZR decreased and the ABA/ZR ratio increased, which might also be providing a protective role against Cd toxicity. PMID:26498815

  8. Acacetin promotes healthy aging by altering stress response in Caenorhabditis elegans.

    Science.gov (United States)

    Asthana, Jyotsna; Mishra, B N; Pandey, Rakesh

    2016-08-01

    The progression in lifespan has been associated with elevated intracellular reactive oxygen species (ROS) and oxidative stress level which contributes to development of age related disorders. The discovery of lifespan modulating phytomolecules may promote development of natural therapies against age related afflictions. Acacetin (5,7-dihydroxy-4-methoxyflavone), is a naturally occurring flavonoid known to possess therapeutic properties. To this end, the present study evaluates effect of acacetin (AC) on lifespan, stress and neurotoxicity for the first time by using well-established free living, multicellular Caenorhabditis elegans model system. The 25 μM dose of AC significantly prolonged the mean lifespan of worms by 27.31% in comparison to untreated control and other tested doses of AC. Additionally, AC enhanced stress resistance against oxidative and thermal stress in worms. Furthermore, AC attenuated age related intracellular ROS level, aggregation of age pigment lipofuscin and increased the mean survival in stress hypersensitive mev-1 mutant by 40.5%. AC supplementation also reduced the alpha synuclein aggregation in transgenic worm model of Parkinson's disease. The enhanced stress resistance, lifespan and alleviation of age related pathology can be attributed to increment in stress modulatory enzymes like superoxide dismutase (SOD) and catalase (CAT) level. Altogether the results suggest AC exposure maintains stress level, health span and extends mean lifespan of C. elegans. The longevity promoting and neuromodulatory effects of AC are mediated by up regulation of the stress response genes sod-3 and gst-4. The present finding gives new insights of natural remedies and their future prospects in developing therapeutic interventions for managing age related diseases. PMID:27150237

  9. Acute stress alters autonomic modulation during sleep in women approaching menopause.

    Science.gov (United States)

    de Zambotti, Massimiliano; Sugarbaker, David; Trinder, John; Colrain, Ian M; Baker, Fiona C

    2016-04-01

    Hot flashes, hormones, and psychosocial factors contribute to insomnia risk in the context of the menopausal transition. Stress is a well-recognized factor implicated in the pathophysiology of insomnia; however the impact of stress on sleep and sleep-related processes in perimenopausal women remains largely unknown. We investigated the effect of an acute experimental stress (impending Trier Social Stress Task in the morning) on pre-sleep measures of cortisol and autonomic arousal in perimenopausal women with and without insomnia that developed in the context of the menopausal transition. In addition, we assessed the macro- and micro-structure of sleep and autonomic functioning during sleep. Following adaptation to the laboratory, twenty two women with (age: 50.4 ± 3.2 years) and eighteen women without (age: 48.5 ± 2.3 years) insomnia had two randomized in-lab overnight recordings: baseline and stress nights. Anticipation of the task resulted in higher pre-sleep salivary cortisol levels and perceived tension, faster heart rate and lower vagal activity, based on heart rate variability measures, in both groups of women. The effect of the stress manipulation on the autonomic nervous system extended into the first 4 h of the night in both groups. However, vagal tone recovered 4-6 h into the stress night in controls but not in the insomnia group. Sleep macrostructure was largely unaltered by the stress, apart from a delayed latency to REM sleep in both groups. Quantitative analysis of non-rapid eye movement sleep microstructure revealed greater electroencephalographic (EEG) power in the beta1 range (15-≤23 Hz), reflecting greater EEG arousal during sleep, on the stress night compared to baseline, in the insomnia group. Hot flash frequency remained similar on both nights for both groups. These results show that pre-sleep stress impacts autonomic nervous system functioning before and during sleep in perimenopausal women with and without insomnia. Findings also indicate

  10. White matter microstructure alterations: a study of alcoholics with and without post-traumatic stress disorder.

    Directory of Open Access Journals (Sweden)

    Caitlin A Durkee

    Full Text Available Many brain imaging studies have demonstrated reductions in gray and white matter volumes in alcoholism, with fewer investigators using diffusion tensor imaging (DTI to examine the integrity of white matter pathways. Among various medical conditions, alcoholism and post-traumatic stress disorder (PTSD are two comorbid diseases that have similar degenerative effects on the white matter integrity. Therefore, understanding and differentiating these effects would be very important in characterizing alcoholism and PTSD. Alcoholics are known to have neurocognitive deficits in decision-making, particularly in decisions related to emotionally-motivated behavior, while individuals with PTSD have deficits in emotional regulation and enhanced fear response. It is widely believed that these types of abnormalities in both alcoholism and PTSD are related to fronto-limbic dysfunction. In addition, previous studies have shown cortico-limbic fiber degradation through fiber tracking in alcoholism. DTI was used to measure white matter fractional anisotropy (FA, which provides information about tissue microstructure, possibly indicating white matter integrity. We quantitatively investigated the microstructure of white matter through whole brain DTI analysis in healthy volunteers (HV and alcohol dependent subjects without PTSD (ALC and with PTSD (ALC+PTSD. These data show significant differences in FA between alcoholics and non-alcoholic HVs, with no significant differences in FA between ALC and ALC+PTSD in any white matter structure. We performed a post-hoc region of interest analysis that allowed us to incorporate multiple covariates into the analysis and found similar results. HV had higher FA in several areas implicated in the reward circuit, emotion, and executive functioning, suggesting that there may be microstructural abnormalities in white matter pathways that contribute to neurocognitive and executive functioning deficits observed in alcoholics. Furthermore

  11. Altered resting-state functional connectivity in post-traumatic stress disorder: a perfusion MRI study

    Science.gov (United States)

    Li, Baojuan; Liu, Jian; Liu, Yang; Lu, Hong-Bing; Yin, Hong

    2013-03-01

    The majority of studies on posttraumatic stress disorder (PTSD) so far have focused on delineating patterns of activations during cognitive processes. Recently, more and more researches have started to investigate functional connectivity in PTSD subjects using BOLD-fMRI. Functional connectivity analysis has been demonstrated as a powerful approach to identify biomarkers of different brain diseases. This study aimed to detect resting-state functional connectivity abnormities in patients with PTSD using arterial spin labeling (ASL) fMRI. As a completely non-invasive technique, ASL allows quantitative estimates of cerebral blood flow (CBF). Compared with BOLD-fMRI, ASL fMRI has many advantages, including less low-frequency signal drifts, superior functional localization, etc. In the current study, ASL images were collected from 10 survivors in mining disaster with recent onset PTSD and 10 survivors without PTSD. Decreased regional CBF in the right middle temporal gyrus, lingual gyrus, and postcentral gyrus was detected in the PTSD patients. Seed-based resting-state functional connectivity analysis was performed using an area in the right middle temporal gyrus as region of interest. Compared with the non-PTSD group, the PTSD subjects demonstrated increased functional connectivity between the right middle temporal gyrus and the right superior temporal gyrus, the left middle temporal gyrus. Meanwhile, decreased functional connectivity between the right middle temporal gyrus and the right postcentral gyrus, the right superior parietal lobule was also found in the PTSD patients. This is the first study which investigated resting-state functional connectivity in PTSD using ASL images. The results may provide new insight into the neural substrates of PTSD.

  12. Electroconvulsive Stimulation, but not Chronic Restraint Stress, Causes Structural Alterations in Adult Rat Hippocampus

    DEFF Research Database (Denmark)

    Olesen, Mikkel V.; Wörtwein, Gitta; Pakkenberg, Bente

    2015-01-01

    The neurobiological mechanisms underlying depression are not fully understood. Only a few previous studies have used validated stereological methods to test how stress and animal paradigms of depression affect adult hippocampal neurogenesis and whether antidepressant therapy can counteract possible...... newly formed neurons in the hippocampal subgranular zone. Also estimated were the total number of neurons and the volume of the granule cell layer in adult rats subjected to chronic restraint stress and electroconvulsive stimulation either alone or in combination. We found that chronic restraint stress...... induces depression-like behavior, without significantly changing neurogenesis, the total number of neurons or the volume of the hippocampus. Further, electroconvulsive stimulation prevents stress-induced depression-like behavior and increases neurogenesis. The total number of neurons and the granule cell...

  13. Stress-induced alterations of left-right electrodermal activity coupling indexed by pointwise transinformation

    Czech Academy of Sciences Publication Activity Database

    Světlák, M.; Bob, P.; Roman, R.; Ježek, S.; Damborská, A.; Chládek, Jan; Shaw, D. J.; Kukleta, M.

    2013-01-01

    Roč. 62, č. 6 (2013), s. 711-719. ISSN 0862-8408 Institutional support: RVO:68081731 Keywords : electrodermal activity * pointwise trasinformation * autonomic nervous system * asymmetry * stress Subject RIV: CE - Biochemistry Impact factor: 1.487, year: 2013

  14. Alterations in the hippocampal glycinergic system in an animal model of posttraumatic stress disorder

    OpenAIRE

    Yamamoto, Shigeto; Morinobu, Shigeru; Iwamoto, Yasuyuki; Ueda, Yuto; Takei, Shiro; FUJITA, Yosuke; Yamawaki, Shigeto

    2010-01-01

    Previous studies have demonstrated that rats subjected to single prolonged stress (SPS) exhibit posttraumatic stress disorder (PTSD)-like symptoms such as enhanced contextual fear in response to trauma related and trauma-unrelated events Furthermore we previously reported that upregulation of hippocampal glycine transporter 1 (GlyT-1) mRNA after context exposure could be the initial mechanism underlying impaired fear extinction in SPS rats To clarify the involvement of the hippocampal glycine...

  15. TISSUE SPECIFIC RESPONSES ALTER THE BIOMASS ACCUMULATION IN WHEAT UNDER GRADUAL AND SUDDEN SALT STRESS

    OpenAIRE

    Yumurtaci A.; Uncuoglu A. A.

    2012-01-01

    Salinity is one the major limiting environmental factors which has negative side effects on crop production. The purpose of this study was to investigate the differences between the gradual and sudden salt stress effects on biomass accumulation associated with whole plant development in three different tissues of two wheat species ( Triticum aestivum and Triticum durum) under hydroponic conditions in the long term. Considering the effects of sudden and gradual stress for biomass accumulation,...

  16. Genome-wide DNA methylation levels and altered cortisol stress reactivity following childhood trauma in humans.

    Science.gov (United States)

    Houtepen, Lotte C; Vinkers, Christiaan H; Carrillo-Roa, Tania; Hiemstra, Marieke; van Lier, Pol A; Meeus, Wim; Branje, Susan; Heim, Christine M; Nemeroff, Charles B; Mill, Jonathan; Schalkwyk, Leonard C; Creyghton, Menno P; Kahn, René S; Joëls, Marian; Binder, Elisabeth B; Boks, Marco P M

    2016-01-01

    DNA methylation likely plays a role in the regulation of human stress reactivity. Here we show that in a genome-wide analysis of blood DNA methylation in 85 healthy individuals, a locus in the Kit ligand gene (KITLG; cg27512205) showed the strongest association with cortisol stress reactivity (P=5.8 × 10(-6)). Replication was obtained in two independent samples using either blood (N=45, P=0.001) or buccal cells (N=255, P=0.004). KITLG methylation strongly mediates the relationship between childhood trauma and cortisol stress reactivity in the discovery sample (32% mediation). Its genomic location, a CpG island shore within an H3K27ac enhancer mark, and the correlation between methylation in the blood and prefrontal cortex provide further evidence that KITLG methylation is functionally relevant for the programming of stress reactivity in the human brain. Our results extend preclinical evidence for epigenetic regulation of stress reactivity to humans and provide leads to enhance our understanding of the neurobiological pathways underlying stress vulnerability. PMID:26997371

  17. Impaired water maze learning performance without altered dopaminergic function in mice heterozygous for the GDNF mutation.

    Science.gov (United States)

    Gerlai, R; McNamara, A; Choi-Lundberg, D L; Armanini, M; Ross, J; Powell-Braxton, L; Phillips, H S

    2001-10-01

    Exogenous glial cell line-derived neurotrophic factor (GDNF) exhibits potent survival-promoting effects on dopaminergic neurons of the nigrostriatal pathway that is implicated in Parkinson's disease and also protects neurons in forebrain ischemia of animal models. However, a role for endogenous GDNF in brain function has not been established. Although mice homozygous for a targeted deletion of the GDNF gene have been generated, these mice die within hours of birth because of deficits in kidney morphogenesis, and, thus, the effect of the absence of GDNF on brain function could not be studied. Herein, we sought to determine whether adult mice, heterozygous for a GDNF mutation on two different genetic backgrounds, demonstrate alterations in the nigrostriatal dopaminergic system or in cognitive function. While both neurochemical and behavioural measures suggested that reduction of GDNF gene expression in the mutant mice does not alter the nigrostriatal dopaminergic system, it led to a significant and selective impairment of performance in the spatial version of the Morris water maze. A standard panel of blood chemistry tests and basic pathological analyses did not reveal alterations in the mutants that could account for the observed performance deficit. These results suggest that endogenous GDNF may not be critical for the development and functioning of the nigrostriatal dopaminergic system but it plays an important role in cognitive abilities. PMID:11683907

  18. Early endocrine alterations reflect prolonged stress and relate to one year functional outcome in patients with severe brain injury

    DEFF Research Database (Denmark)

    Marina, Djordje; Klose, Marianne; Nordenbo, Annette;

    2015-01-01

    OBJECTIVE: Severe brain injury poses a risk of developing acute and chronic hypopituitarism. Pituitary hormone alterations developed in the early recovery phase after brain injury may have implications for long-term functional recovery. The objective was to assess the pattern and prevalence of......-Extended. RESULTS: Three months after the injury, elevated stress hormones (i.e. 30 min. stimulated cortisol, prolactin and/or insulin-like growth factor 1) and/or suppressed gonadal- or thyroid hormones were recorded in 68% and 32% of the patients, respectively. At one year, lower functioning level (Functional...

  19. Implications of Altered Glutathione Metabolism in Aspirin-Induced Oxidative Stress and Mitochondrial Dysfunction in HepG2 Cells

    OpenAIRE

    Raza, Haider; John, Annie

    2012-01-01

    We have previously reported that acetylsalicylic acid (aspirin, ASA) induces cell cycle arrest, oxidative stress and mitochondrial dysfunction in HepG2 cells. In the present study, we have further elucidated that altered glutathione (GSH)-redox metabolism in HepG2 cells play a critical role in ASA-induced cytotoxicity. Using selected doses and time point for ASA toxicity, we have demonstrated that when GSH synthesis is inhibited in HepG2 cells by buthionine sulfoximine (BSO), prior to ASA tre...

  20. Nutritional Ketosis Alters Fuel Preference and Thereby Endurance Performance in Athletes.

    Science.gov (United States)

    Cox, Pete J; Kirk, Tom; Ashmore, Tom; Willerton, Kristof; Evans, Rhys; Smith, Alan; Murray, Andrew J; Stubbs, Brianna; West, James; McLure, Stewart W; King, M Todd; Dodd, Michael S; Holloway, Cameron; Neubauer, Stefan; Drawer, Scott; Veech, Richard L; Griffin, Julian L; Clarke, Kieran

    2016-08-01

    Ketosis, the metabolic response to energy crisis, is a mechanism to sustain life by altering oxidative fuel selection. Often overlooked for its metabolic potential, ketosis is poorly understood outside of starvation or diabetic crisis. Thus, we studied the biochemical advantages of ketosis in humans using a ketone ester-based form of nutrition without the unwanted milieu of endogenous ketone body production by caloric or carbohydrate restriction. In five separate studies of 39 high-performance athletes, we show how this unique metabolic state improves physical endurance by altering fuel competition for oxidative respiration. Ketosis decreased muscle glycolysis and plasma lactate concentrations, while providing an alternative substrate for oxidative phosphorylation. Ketosis increased intramuscular triacylglycerol oxidation during exercise, even in the presence of normal muscle glycogen, co-ingested carbohydrate and elevated insulin. These findings may hold clues to greater human potential and a better understanding of fuel metabolism in health and disease. PMID:27475046

  1. Identification of resilient individuals and those at risk for performance deficits under stress

    OpenAIRE

    Winslow, Brent D.; Carroll, Meredith B.; Martin, Jonathan W.; Surpris, Glenn; Chadderdon, George L.

    2015-01-01

    Human task performance is affected by exposure to physiological and psychological stress. The ability to measure the physiological response to stressors and correlate that to task performance could be used to identify resilient individuals or those at risk for stress-related performance decrements. Accomplishing this prior to performance under severe stress or the development of clinical stress disorders could facilitate focused preparation such as tailoring training to individual needs. Here...

  2. Quantitative proteomic analysis of cabernet sauvignon grape cells exposed to thermal stresses reveals alterations in sugar and phenylpropanoid metabolism.

    Science.gov (United States)

    George, Iniga S; Pascovici, Dana; Mirzaei, Mehdi; Haynes, Paul A

    2015-09-01

    Grapes (Vitis vinifera) are a valuable fruit crop and wine production is a major industry. Global warming and expanded range of cultivation will expose grapes to more temperature stresses in future. Our study investigated protein level responses to abiotic stresses, with particular reference to proteomic changes induced by the impact of four different temperature stress regimes, including both hot and cold temperatures, on cultured grape cells. Cabernet Sauvignon cell suspension cultures grown at 26°C were subjected to 14 h of exposure to 34 and 42°C for heat stress, and 18 and 10°C for cold stress. Cells from the five temperatures were harvested in biological triplicates and label-free quantitative shotgun proteomic analysis was performed. A total of 2042 non-redundant proteins were identified from the five temperature points. Fifty-five proteins were only detected in extreme heat stress conditions (42°C) and 53 proteins were only detected at extreme cold stress conditions (10°C). Gene Ontology (GO) annotations of differentially expressed proteins provided insights into the metabolic pathways that are involved in temperature stress in grape cells. Sugar metabolism displayed switching between alternative and classical pathways during temperature stresses. Additionally, nine proteins involved in the phenylpropanoid pathway were greatly increased in abundance at extreme cold stress, and were thus found to be cold-responsive proteins. All MS data have been deposited in the ProteomeXchange with identifier PXD000977 (http://proteomecentral.proteomexchange.org/dataset/PXD000977). PMID:25959233

  3. Perceived stress predicts altered reward and loss feedback processing in medial prefrontal cortex

    Directory of Open Access Journals (Sweden)

    Michael T Treadway

    2013-05-01

    Full Text Available Stress is significant risk factor for the development of psychopathology, particularly symptoms related to reward processing. Importantly, individuals display marked variation in how they perceive and cope with stressful events, and such differences are strongly linked to risk for developing psychiatric symptoms following stress exposure. However, many questions remain regarding the neural architecture that underlies inter-subject variability in perceptions of stressors. Using functional magnetic resonance imaging (fMRI during a monetary incentive delay paradigm, we examined the effects of self-reported perceived stress levels on neural activity during reward anticipation and feedback in a sample of healthy individuals. We found that subjects reporting more uncontrollable and overwhelming stressors displayed blunted neural responses in medial prefrontal cortex (mPFC following feedback related to monetary gains as well monetary losses. This is consistent with preclinical models that implicate the mPFC as a key site of vulnerability to the noxious effects of uncontrollable stressors. Our data help translate these findings to humans, and elucidate some of the neural mechanisms that may underlie stress-linked risk for developing reward-related psychiatric symptoms.

  4. Proteomic Alterations of Antarctic Ice Microalga Chlamydomonas sp. Under Low-Temperature Stress

    Institute of Scientific and Technical Information of China (English)

    Guang-Feng Kan; Jin-Lai Miao; Cui-Juan Shi; Guang-You Li

    2006-01-01

    Antarctic ice microalga can survive and thrive in cold channels or pores in the Antarctic ice layer. In order to understand the adaptive mechanisms to low temperature, in the present study we compared two-dimensional polyacrylamide gel electrophoresis (2-DE) profiles of normal and low temperature-stressed Antarctic ice microalga Chlamydomonas sp. cells. In addition, new protein spots induced by low temperature were identified with peptide mass fingerprinting based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and database searching. Well-resolved and reproducible 2-DE patterns of both normal and low temperature-stressed cells were acquired. A total of 626 spots was detected in control cells and 652 spots were detected in the corresponding low temperature-stressed cells. A total of 598 spots was matched between normal and stressed cells. Two newly synthesized proteins (a and b) in low temperature-stressed cells were characterized. Protein spot A (53 kDa, pI 6.0) was similar to isopropylmalate/homocitrate/citramalate synthases, which act in the transport and metabolism of amino acids. Protein spot b (25 kDa, pI 8.0) was related to glutathione S-transferase, which functions as a scavenger of active oxygen, free radicals, and noxious metabolites. The present study is valuable for the application of ice microalgae, establishing an ice microalga Chlamydomonas sp. proteome database, and screening molecular biomarkers for further studies.

  5. Molecular basis for arsenic-Induced alteration in nitric oxide production and oxidative stress: implication of endothelial dysfunction

    International Nuclear Information System (INIS)

    Accumulated epidemiological studies have suggested that prolonged exposure of humans to arsenic in drinking water is associated with vascular diseases. The exact mechanism of how this occurs currently unknown. Nitric oxide (NO), formed by endothelial NO synthase (eNOS), plays a crucial role in the vascular system. Decreased availability of biologically active NO in the endothelium is implicated in the pathophysiology of several vascular diseases and inhibition of eNOS by arsenic is one of the proposed mechanism s for arsenic-induced vascular diseases. In addition, during exposure to arsenic, overproduction of reactive oxygen species (ROS) can occur, resulting in oxidative stress, which is another major risk factor for vascular dysfunction. The molecular basis for decreased NO levels and increased oxidative stress during arsenic exposure is poorly understood. In this article, evidence for arsenic-mediated alteration in NO production and oxidative stress is reviewed. The results of a cross-sectional study in an endemic area of chronic arsenic poisoning and experimental animal studies to elucidate a potential mechanism for the impairment of NO formation and oxidative stress caused by prolonged exposure to arsenate in the drinking water are also reviewed

  6. Mild Traumatic Brain Injury with Social Defeat Stress Alters Anxiety, Contextual Fear Extinction, and Limbic Monoamines in Adult Rats.

    Science.gov (United States)

    Davies, Daniel R; Olson, Dawne; Meyer, Danielle L; Scholl, Jamie L; Watt, Michael J; Manzerra, Pasquale; Renner, Kenneth J; Forster, Gina L

    2016-01-01

    Mild traumatic brain injury (mTBI) produces symptoms similar to those typifying posttraumatic stress disorder (PTSD) in humans. We sought to determine whether a rodent model of stress concurrent with mTBI produces characteristics of PTSD such as impaired contextual fear extinction, while also examining concurrent alterations to limbic monoamine activity in brain regions relevant to fear and anxiety states. Male rats were exposed to social stress or control conditions immediately prior to mTBI induction, and 6 days later were tested either for anxiety-like behavior using the elevated plus maze (EPM), or for contextual fear conditioning and extinction. Brains were collected 24 h after EPM testing, and tissue from various limbic regions analyzed for content of monoamines, their precursors and metabolites using HPLC with electrochemical detection. Either social defeat or mTBI alone decreased time spent in open arms of the EPM, indicating greater anxiety-like behavior. However, this effect was enhanced by the combination of treatments. Further, rats exposed to both social defeat and mTBI exhibited greater freezing within extinction sessions compared to all other groups, suggesting impaired contextual fear extinction. Social defeat combined with mTBI also had greater effects on limbic monoamines than either insult alone, particularly with respect to serotonergic effects associated with anxiety and fear learning. The results suggest social stress concurrent with mTBI produces provides a relevant animal model for studying the prevention and treatment of post-concussive psychobiological outcomes. PMID:27147992

  7. AMP Kinase Activation Alters Oxidant-Induced Stress Granule Assembly by Modulating Cell Signaling and Microtubule Organization.

    Science.gov (United States)

    Mahboubi, Hicham; Koromilas, Antonis E; Stochaj, Ursula

    2016-10-01

    Eukaryotic cells assemble stress granules (SGs) when translation initiation is inhibited. Different cell signaling pathways regulate SG production. Particularly relevant to this process is 5'-AMP-activated protein kinase (AMPK), which functions as a stress sensor and is transiently activated by adverse physiologic conditions. Here, we dissected the role of AMPK for oxidant-induced SG formation. Our studies identified multiple steps of de novo SG assembly that are controlled by the kinase. Single-cell analyses demonstrated that pharmacological AMPK activation prior to stress exposure changed SG properties, because the granules became more abundant and smaller in size. These altered SG characteristics correlated with specific changes in cell survival, cell signaling, cytoskeletal organization, and the abundance of translation initiation factors. Specifically, AMPK activation increased stress-induced eukaryotic initiation factor (eIF) 2α phosphorylation and reduced the concentration of eIF4F complex subunits eIF4G and eIF4E. At the same time, the abundance of histone deacetylase 6 (HDAC6) was diminished. This loss of HDAC6 was accompanied by increased acetylation of α-tubulin on Lys40. Pharmacological studies further confirmed this novel AMPK-HDAC6 interplay and its importance for SG biology. Taken together, we provide mechanistic insights into the regulation of SG formation. We propose that AMPK activation stimulates oxidant-induced SG formation but limits their fusion into larger granules. PMID:27430620

  8. Selected sperm traits are simultaneously altered after scrotal heat stress and play specific roles in in vitro fertilization and embryonic development.

    Science.gov (United States)

    Lucio, Aline C; Alves, Benner G; Alves, Kele A; Martins, Muller C; Braga, Lucas S; Miglio, Luisa; Alves, Bruna G; Silva, Thiago H; Jacomini, José O; Beletti, Marcelo E

    2016-09-01

    Improvements in the estimation of male fertility indicators require advances in laboratory tests for sperm assessment. The aims of the present work were (1) to apply a multivariate analysis to examine sperm set of alterations and interactions and (2) to evaluate the importance of sperm parameters on the outcome of standard IVF and embryonic development. Bulls (n = 3) were subjected to scrotal insulation, and ejaculates were collected before (preinsulation = Day 0) and through 56 days (Days 7, 14, 21, 28, 35, 42, 49, and 56) of the experimental period. Sperm head morphometry and chromatin variables were assessed by a computational image analysis, and IVF was performed. Scrotal heat stress induced alterations in all evaluated sperm head features, as well as cleavage and blastocyst rates. A principal component analysis revealed three main components (factors) that represented almost 89% of the cumulative variance. In addition, an association of factor scores with cleavage (factor 1) and blastocyst (factor 3) rates was observed. In conclusion, several sperm traits were simultaneously altered as a result of a thermal insult. These sperm traits likely play specific roles in IVF and embryonic development. PMID:27087533

  9. Effects of quercetin on predator stress-related hematological and behavioral alterations in pregnant rats and their offspring

    Indian Academy of Sciences (India)

    Mohamed L Toumi; Sameha Merzoug; Abdelkrim Tahraoui

    2016-06-01

    This study aims at investigating the effect of a psychogenic stress during gestation on the behaviour and haematological indices in dams as well as on the neonatal haematological status and periadolescent behaviour in their offspring. Moreover, the ability of quercetin, a natural flavonoid, to prevent the stress-induced changes was estimated. Pregnant Wistar rats were pretreated with quercetin before the exposure to a predator stress on gestational day 19. Post-stress maternal anxiety-like behaviour was assessed with a concomitant haematological analysis. In the offspring, haematological analysis and behavioural testing were performed during the postnatal stage. Our results revealed that predator stress causes an anxiety-like behaviour in dams along with a decrease in erythrocytes, a microcytosis, and a thrombocytosis. Prenatally stressed neonates manifested microcytosis and thrombocytosis with a significant polycythemia. Signs of motor hyperactivity, anxiety-like behaviour, and memory dysfunction were detected at periadolescence. Quercetin pretreatment alleviated the stress-induced behavioural and haematological impairments in dams but failed to attenuate the haematological changes in neonates. A sex-dependent effect of quercetin on behaviour was found at periadolescence. Our findings suggest that, besides a beneficial effect on haematological and behavioural anomalies in traumatized dams, quercetin may lastingly modulate the behaviour of their progeny.

  10. Effects of quercetin on predator stress-related hematological and behavioral alterations in pregnant rats and their offspring.

    Science.gov (United States)

    Toumi, Mohamed L; Merzoug, Sameha; Tahraoui, Abdelkrim

    2016-06-01

    This study aims at investigating the effect of a psychogenic stress during gestation on the behaviour and haematological indices in dams as well as on the neonatal haematological status and periadolescent behaviour in their offspring. Moreover, the ability of quercetin, a natural flavonoid, to prevent the stress-induced changes was estimated. Pregnant Wistar rats were pretreated with quercetin before the exposure to a predator stress on gestational day 19. Post-stress maternal anxiety-like behaviour was assessed with a concomitant haematological analysis. In the offspring, haematological analysis and behavioural testing were performed during the postnatal stage. Our results revealed that predator stress causes an anxiety-like behaviour in dams along with a decrease in erythrocytes, a microcytosis, and a thrombocytosis. Prenatally stressed neonates manifested microcytosis and thrombocytosis with a significant polycythemia. Signs of motor hyperactivity, anxiety-like behaviour, and memory dysfunction were detected at periadolescence. Quercetin pretreatment alleviated the stress-induced behavioural and haematological impairments in dams but failed to attenuate the haematological changes in neonates. A sex-dependent effect of quercetin on behaviour was found at periadolescence. Our findings suggest that, besides a beneficial effect on haematological and behavioural anomalies in traumatized dams, quercetin may lastingly modulate the behaviour of their progeny. PMID:27240984

  11. Alteration in delayed fluorescence characterize the effect of heat stress on plants

    Science.gov (United States)

    Zeng, Lizhang; Xing, Da

    2005-02-01

    High temperature affects the photosynthetic functions of plants by its effects on the rate of chemical reactions and on structural organization. Delayed fluorescence originated from the reaction center of photosystem II (PSII) during the photosynthesis process shortly after stopped illumination. With lamina of soybean as a testing model, the effects of high temperature stress on plant photosynthesis capability were studied with various spectral analysis methods. Experimental results show that DF spectrum and Excitation spectrum can probably characterize the changes of soybean photosynthesis capability after different high temperature treatments. Meanwhile, the injury and harm degree of heat stress on soybean leaves were further studied by the variability of its chloroplast absorption spectrum. DF spectroscopy method may provide a new approach for fast detection of the effects of environment stresses on plant photosynthesis capability.

  12. Altered DNA repair, oxidative stress and antioxidant status in coronary artery disease

    Indian Academy of Sciences (India)

    A Supriya Simon; V Chithra; Anoop Vijayan; Roy D Dinesh; T Vijayakumar

    2013-06-01

    Coronary artery disease (CAD) is a multifactorial disease caused by the interplay of environmental risk factors with multiple predisposing genes. The present study was undertaken to evaluate the role of DNA repair efficiency and oxidative stress and antioxidant status in CAD patients. Malonaldehyde (MDA), which is an indicator of oxidative stress, and mean break per cell (b/c) values, which is an indicator of decreased DNA repair efficiency, were found to be significantly increased in patients compared to normal controls ( < 0.05) whereas ascorbic acid and GSH were found to be lower among patients than the control group. It has been found that elevated oxidative stress decreased antioxidant level and decreased DNA repair efficiency can contribute to the development of CAD. This study also showed that high MDA, low ascorbic acid and GSH were significantly associated with high b/c value.

  13. Altered immunological response in mice subjected to stress and exposed to fungal spores

    Science.gov (United States)

    Kurup, Viswanath P.; Choi, Hongyung; Kumar, Anoopa; Murali, Pazhayannur S.; Mishra, S. K.; Pierson, Duane L.

    1992-01-01

    Space flight and related factors such as stress appear to have an adverse effect on astronauts' immune systems. The presence of potentially pathogenic microbes including several genera of fungi reported from spacecraft environment may be a cause of concern in such situations. In order to study the role of such organisms in causing opportunistic or allergic diseases in crewmembers, we have tried to develop an animal model. BALB/c mice were suspended upside down for varying periods of time to induce stress, and their lymphocyte functions were evaluated. These studies indicate that the stress resulted in lowered mitogen induced lymphocyte stimulation as represented by 3H-thymidine uptake. We have also studied the ability of these animals to respond to Aspergillus fumigatus spores. The results of the study clearly demonstrate a definite down-regulation in T-cell proliferation and a higher incidence of infection with A. fumigatus.

  14. Tissue specific responses alter the biomass accumulation in wheat under gradual and sudden salt stress

    Directory of Open Access Journals (Sweden)

    Yumurtaci A.

    2012-11-01

    Full Text Available Salinity is one the major limiting environmental factors which has negative side effects on crop production. The purpose of this study was to investigate the differences between the gradual and sudden salt stress effects on biomass accumulation associated with whole plant development in three different tissues of two wheat species ( Triticum aestivum and Triticum durum under hydroponic conditions in the long term. Considering the effects of sudden and gradual stress for biomass accumulation, while importance of salinity x genotype interaction for fresh weights was 5%, association for salinity x tissue type was found as 1% important. Interestingly, root branching and development of lateral roots were much more negatively affected by gradual stress rather than sudden salt application. Our results demonstrated that root and leaf were both critical tissues to test the salt tolerance by physiologically but sheath tissue might be used as an alternative source of variation for solving the interactions between root and leaves in wheat.

  15. Genome-wide DNA methylation levels and altered cortisol stress reactivity following childhood trauma in humans

    OpenAIRE

    Houtepen, Lotte C; Vinkers, Christiaan H.; Carrillo-Roa, Tania; Hiemstra, Marieke; van Lier, Pol A; Meeus, Wim; Branje, Susan; Heim, Christine M; Nemeroff, Charles B.; Mill, Jonathan; Schalkwyk, Leonard C.; Creyghton, Menno P.; René S. Kahn; Joëls, Marian; Binder, Elisabeth B.

    2016-01-01

    DNA methylation likely plays a role in the regulation of human stress reactivity. Here we show that in a genome-wide analysis of blood DNA methylation in 85 healthy individuals, a locus in the Kit ligand gene (KITLG; cg27512205) showed the strongest association with cortisol stress reactivity (P=5.8 × 10(-6)). Replication was obtained in two independent samples using either blood (N=45, P=0.001) or buccal cells (N=255, P=0.004). KITLG methylation strongly mediates the relationship between chi...

  16. Stress-restress evokes sustained iNOS activity and altered GABA levels and NMDA receptors in rat hippocampus

    DEFF Research Database (Denmark)

    Harvey, Brian H; Oosthuizen, Frasia; Brand, Linda;

    2004-01-01

    RATIONALE: Stress-related glucocorticoid and glutamate release have been implicated in hippocampal atrophy evident in patients with post-traumatic stress disorder (PTSD). Glutamatergic mechanisms activate nitric oxide synthase (NOS), while gamma-amino-butyric acid (GABA) may inhibit both...... glutamatergic and nitrergic transmission. Animal studies support a role for NOS in stress. OBJECTIVES: We have studied the role of NOS and glucocorticoids, as well as inhibitory and excitatory transmitters, in a putative animal model of PTSD that emphasizes repeated trauma. METHODS: Hippocampal NOS activity, N......-methyl-D-aspartate (NMDA) receptor binding characteristics and GABA levels were studied in Sprague-Dawley rats 21 days after exposure to a stress-restress paradigm, using radiometric analysis, radioligand studies and high-performance liquid chromatography (HPLC) analysis with electrochemical detection, respectively...

  17. Identification of Resilient Individuals and Those at Risk for Performance Deficits under Stress

    Directory of Open Access Journals (Sweden)

    Brent eWinslow

    2015-09-01

    Full Text Available Human task performance is affected by exposure to physiological and psychological stress. The ability to measure the physiological response to stressors and correlate that to task performance could be used to identify resilient individuals or those at risk for stress-related performance decrements. Accomplishing this prior to performance under severe stress or the development of clinical stress disorders could facilitate focused preparation such as tailoring training to individual needs. Here we measure the effects of stress on physiological response and performance through behavior, physiological sensors, and subjective ratings, and identify which individuals are at risk for stress-related performance decrements. Participants performed military-relevant training tasks under stress in a virtual environment, with autonomic and hypothalamic-pituitary-adrenal axis (HPA reactivity analyzed. Self-reported stress, as well as physiological indices of stress, increased in the group pre-exposed to socioevaluative stress. Stress response was effectively captured via electrodermal and cardiovascular measures of heart rate and skin conductance level. A resilience classification algorithm was developed based upon physiological reactivity, which correlated with baseline unstressed physiological and self-reported stress values. Outliers were identified in the experimental group that had a significant mismatch between self-reported stress and salivary cortisol. Baseline stress measurements were predictive of individual resilience to stress, including the impact stress had on physiological reactivity and performance. Such an approach may have utility in identifying individuals at risk for problems performing under severe stress. Continuing work has focused on adapting this method for military personnel, and assessing the utility of various coping and decision-making strategies on performance and physiological stress.

  18. Prenatal transportation stress alters temperament and serum cortisol concentrations in suckling Brahman calves.

    Science.gov (United States)

    Littlejohn, B P; Price, D M; Banta, J P; Lewis, A W; Neuendorff, D A; Carroll, J A; Vann, R C; Welsh, T H; Randel, R D

    2016-02-01

    This experiment examined the relationship between prenatal stress and subsequent calf temperament through weaning. The prenatal stressor used was repeated transportation of pregnant Brahman cows for 2 h at 60 ± 5, 80 ± 5, 100 ± 5, 120 ± 5, and 140 ± 5 d of gestation. Prenatally stressed calves ( = 41) were compared with controls ( = 44; dams did not undergo transportation during pregnancy) from 2 wk of age until weaning (average age at weaning = 174.8 ± 1.3 d). Temperament was defined by pen score (PS; 1 = calm and 5 = excitable), exit velocity (EV; m/sec), and temperament score (TS; (PS + EV)/2) and was recorded for each calf on d -168, -140, -112, -84, -56, -28, and 0 relative to weaning (d 0 = weaning). Cortisol concentrations were determined in serum samples obtained on d -168, -140, -28, and 0 relative to weaning. Birth weight and weaning weight were not different between treatment groups ( > 0.1). Pen score was greater ( = 0.03) in prenatally stressed calves (2.84 ± 0.21) relative to controls (2.31 ± 0.21). Exit velocity was greater ( Brahman calves that were prenatally stressed were more temperamental and had greater circulating serum concentrations of cortisol than control calves. PMID:27065130

  19. Salt stress induced lipid accumulation in heterotrophic culture cells of Chlorella protothecoides: Mechanisms based on the multi-level analysis of oxidative response, key enzyme activity and biochemical alteration.

    Science.gov (United States)

    Wang, Tao; Ge, Haiyan; Liu, Tingting; Tian, Xiwei; Wang, Zejian; Guo, Meijin; Chu, Ju; Zhuang, Yingping

    2016-06-20

    Salt stress as an effective stress factor that could improve the lipid content and lipid yield of glucose in the heterotrophic culture cells of Chlorella protothecoides was demonstrated in this study. The highest lipid content of 41.2% and lipid yield of 185.8mg/g were obtained when C. protothecoides was stressed under 30g/L NaCl condition at its late logarithmic growth phase. Moreover, the effects of salt and osmotic stress on lipid accumulation were comparatively analyzed, and it was found that the effects of NaCl and KCl stress had no significant differences at the same osmolarity level of 1150mOsm/kg with lipid contents of 41.7 and 40.8% as well as lipid yields of 192.9 and 186.8mg/g, respectively, whereas these results were obviously higher than those obtained under the iso-osmotic glycerol and sorbitol stresses. Furthermore, basing on the multi-level analysis of oxidative response, key enzyme activity and biochemical alteration, the superior performance of salt stress driving lipid over-synthesis was probably ascribed to the more ROS production as a result of additional ion effect besides the osmotic effect, subsequently mediating the alteration from carbohydrate storage to lipid accumulation in signal transduction process of C. protothecoides. PMID:27085889

  20. Sleep alterations following exposure to stress predict fear-associated memory impairments in a rodent model of PTSD.

    Science.gov (United States)

    Vanderheyden, William M; George, Sophie A; Urpa, Lea; Kehoe, Michaela; Liberzon, Israel; Poe, Gina R

    2015-08-01

    Sleep abnormalities, such as insomnia, nightmares, hyper-arousal, and difficulty initiating or maintaining sleep, are diagnostic criteria of posttraumatic stress disorder (PTSD). The vivid dream state, rapid eye movement (REM) sleep, has been implicated in processing emotional memories. We have hypothesized that REM sleep is maladaptive in those suffering from PTSD. However, the precise neurobiological mechanisms regulating sleep disturbances following trauma exposure are poorly understood. Using single prolonged stress (SPS), a well-validated rodent model of PTSD, we measured sleep alterations in response to stressor exposure and over a subsequent 7-day isolation period during which the PTSD-like phenotype develops. SPS resulted in acute increases in REM sleep and transition to REM sleep, and decreased waking in addition to alterations in sleep architecture. The severity of the PTSD-like phenotype was later assessed by measuring freezing levels on a fear-associated memory test. Interestingly, the change in REM sleep following SPS was significantly correlated with freezing behavior during extinction recall assessed more than a week later. Reductions in theta (4-10 Hz) and sigma (10-15 Hz) band power during transition to REM sleep also correlated with impaired fear-associated memory processing. These data reveal that changes in REM sleep, transition to REM sleep, waking, and theta and sigma power may serve as sleep biomarkers to identify individuals with increased susceptibility to PTSD following trauma exposure. PMID:26019008

  1. Study of Physiological and Biochemical Alterations in Cyanobacterium under Organic Stress

    Directory of Open Access Journals (Sweden)

    Shanthy Sundaram

    2011-01-01

    Full Text Available Combining nitrogen fixation with other bacterial metabolic capabilities to convert the waste carbon into useful raw materials would be a highly desirable further enhancement to the process. To study the possibility of further enhancement of the value proposition of waste remediation from cost-neutrality to profitability, we can use nitrogen-fixing or non nitrogen fixing cyanobacteria that also naturally accumulate effluent from remediating materials. A filamentous heterocystous cyanobacterium, Nostoc muscorum, unicellular-non heterocystous cyanobacterium, Synechococcus PCC 7942, filamentous non heterocystous cyanobacterium, Spirulina platensis and heterocystous filamentous cyanobacterium Anabaena cylindrica, have the ability to degrade industrial pollutants such as benzene, toluene and xylene. We have done the growth measurements and estimated the amount of pigments like chlorophyll-a, carotenoids, phycocyanin. We also have studied the accumulation of total peroxide radicals and lipid peroxidation due to accumulation of MDA and stress busters such as ascorbate, proline, glutathione etc under all the above stress. Total antioxidant activity of cyanobacteria is measured by TBARS assay. We have also studied the enzymes involved in the antioxidant mechanism like superoxide dismutase and peroxidase. The amount of pigments started decreasing as the concentration of the stress increased. But, the amount of ascorbate and proline and other antioxidant activities increased under stress. This suggests that cyanobacteria may be able to survive under organic stress. Biodegradation is increasingly being considered as a less expensive alternative to physical and chemical means of decomposing organic pollutants. Biosensors may be designed to indicate and estimate pollutants in natural wastes, using PS2 particles/ thylakoids/spheroplasts.

  2. STRESS MANAGEMENT

    Directory of Open Access Journals (Sweden)

    Charu Jain

    2015-02-01

    Full Text Available Everyone has the right to live their life very happily. But the question arises,“Do they really live their life happily”. The answer is “No”. Human beings are not living their life happily because of stress, tension and depression in their life. Due to stress, tension and depression, a person cannot focus on their work properly and as a result of this, their focus from the work has been diverted, results in bad performance at home and at work. In this article, my focus is on stress management and how to reduce stress. Stress management encompasses those techniques which helps the human beings to survive their life by reducing stress. Stress can come at any stage of life. Stress can’t be removed totally but it can be reduced and alter. Stress management plays a vital role in human being life.

  3. Long-term in vivo polychlorinated biphenyl 126 exposure induces oxidative stress and alters proteomic profile on islets of Langerhans

    Science.gov (United States)

    Loiola, Rodrigo Azevedo; Dos Anjos, Fabyana Maria; Shimada, Ana Lúcia; Cruz, Wesley Soares; Drewes, Carine Cristiane; Rodrigues, Stephen Fernandes; Cardozo, Karina Helena Morais; Carvalho, Valdemir Melechco; Pinto, Ernani; Farsky, Sandra Helena

    2016-06-01

    It has been recently proposed that exposure to polychlorinated biphenyls (PCBs) is a risk factor to type 2 diabetes mellitus (DM2). We investigated this hypothesis using long-term in vivo PCB126 exposure to rats addressing metabolic, cellular and proteomic parameters. Male Wistar rats were exposed to PCB126 (0.1, 1 or 10 μg/kg of body weight/day; for 15 days) or vehicle by intranasal instillation. Systemic alterations were quantified by body weight, insulin and glucose tolerance, and blood biochemical profile. Pancreatic toxicity was measured by inflammatory parameters, cell viability and cycle, free radical generation, and proteomic profile on islets of Langerhans. In vivo PCB126 exposure enhanced the body weight gain, impaired insulin sensitivity, reduced adipose tissue deposit, and elevated serum triglycerides, cholesterol, and insulin levels. Inflammatory parameters in the pancreas and cell morphology, viability and cycle were not altered in islets of Langerhans. Nevertheless, in vivo PCB126 exposure increased free radical generation and modified the expression of proteins related to oxidative stress on islets of Langerhans, which are indicative of early β-cell failure. Data herein obtained show that long-term in vivo PCB126 exposure through intranasal route induced alterations on islets of Langerhans related to early end points of DM2.

  4. Effect of orthostatic stress on exercise performance after bedrest

    Science.gov (United States)

    Convertino, V. A.; Goldwater, D. J.; Sandler, H.

    1982-01-01

    The cardiorespiratory responses to supine against upright exercise were compared to determine the orthostatic effects of gravity on exercise performance following bedrest. Five healthy male subjects underwent seven days of continuous bedrest. A deconditioning effect was manifested by significant increases in ventilation volume, carbon dioxide production, respiratory exchange ratio, heart rate, heart rate-pressure product, and diastolic blood pressure during submaximal exercise following bedrest. The major finding from this study was that bedrest resulted in a general decrease in exercise tolerance, which was more stressful in the upright posture compared to the supine position, judging from specific submaximal cardiorespiratory responses to cycle ergometry. The data support the hypothesis that there is an orthostatic factor to the reduction in work tolerance following bedrest deconditioning, in addition to the effects caused by increased physical activity.

  5. Altered consolidation of extinction-like inhibitory learning in genotype-specific dysfunctional coping fostered by chronic stress in mice.

    Science.gov (United States)

    Campus, P; Maiolati, M; Orsini, C; Cabib, S

    2016-12-15

    Genetic and stress-related factors interact to foster mental disorders, possibly through dysfunctional learning. In a previous study we reported that a temporary experience of reduced food availability increases forced swim (FS)-induced helplessness tested 14days after a first experience in mice of the standard inbred C57BL/6(B6) strain but reduces it in mice of the genetically unrelated DBA/2J (D2) strain. Because persistence of FS-induced helplessness influences adaptive coping with stress challenge and involve learning processes the present study tested whether the behavioral effects of restricted feeding involved altered consolidation of FS-related learning. First, we demonstrated that restricted feeding does not influence behavior expressed on the first FS experience, supporting a specific effect on persistence rather then development of helplessness. Second, we found that FS-induced c-fos expression in the infralimbic cortex (IL) was selectively enhanced in food-restricted (FR) B6 mice and reduced in FR D2 mice, supporting opposite alterations of consolidation processes involving this brain area. Third, we demonstrated that immediate post-FS inactivation of IL prevents 24h retention of acquired helplessness by continuously free-fed mice of both strains, indicating the requirement of a functioning IL for consolidation of FS-related learning in either mouse strain. Finally, in line with the known role of IL in consolidation of extinction memories, we found that restricted feeding selectively facilitated 24h retention of an acquired extinction in B6 mice whereas impairing it in D2 mice. These findings support the conclusion that an experience of reduced food availability strain-specifically affects persistence of newly acquired passive coping strategies by altering consolidation of extinction-like inhibitory learning. PMID:27506654

  6. Nanometals induce stress and alter thyroid hormone action in amphibia at or below North American water quality guidelines.

    Science.gov (United States)

    Hinther, Ashley; Vawda, Saadia; Skirrow, Rachel C; Veldhoen, Nik; Collins, Patricia; Cullen, Jay T; van Aggelen, Graham; Helbing, Caren C

    2010-11-01

    Nanometals are manufactured to particle sizes with diameters in the nanometer range and are included in a variety of consumer and health products. There is a lack of information regarding potential effects of these materials on aquatic organisms. Amphibians are regarded as environmental sentinels and demonstrate an exquisite sensitivity to thyroid hormone action, a hormone that is essential for human health. This present study assessed the effect of exposure to nanometals on stress and thyroid hormone signaling in frog tissue using a cultured tail fin biopsy (C-fin) assay derived from Rana catesbeiana tadpoles. The C-fin assay maintains tissue complexity and biological replication while multiple chemical responses can be assessed from the same individual. We tested the ability of nanosilver (0.06 μg/L-5.5 mg/L), quantum dots (0.25 μg/L-22 mg/L), and nanozinc oxide (0.19-10 mg/L) to alter gene expression in the presence or absence of 3,3',5'-triiodothyronine (T(3)) using quantitative real-time polymerase chain reaction. Results were compared to exposure to micrometer-silver, silver nitrate, and micrometer-cadmium telluride. Nanosilver (≥2.75 mg/L) and quantum dots (≥0.22 mg/L) altered the expression of transcripts linked to T(3)- and stress-mediated pathways, while nanozinc oxide had no effect. Lower concentrations of nanosilver (0.6 to 550 μg/L) perturbed T(3)-mediated signaling while not inducing cell stress. The observed effects were orders of magnitude below acute toxicity levels and occurred at or below the current North American water quality guidelines for metals, underscoring the need for evaluating nanoparticles separately from their constituent chemicals. PMID:20929207

  7. Effect of heat stress on histopathological alterations in kidneys of albino rats

    Directory of Open Access Journals (Sweden)

    Sabah S.A. Al-Tekrity

    2011-02-01

    Full Text Available The effect of heat stress was studied over two months (July and August by using thirty adult male rats. The animals were divided into six groups (five animals per each group and tested for 7, 14, 21, 28, 35 and 42 days, under controlled condition (45±5°C. The clinical observation indicated significant decrease in activity and body weight associated with oligourea and hypophagia. All these signs were prominent after five days of the experiment. The kidneys of rats under heat stress showed degenerated glomeruli began at 7th day of the study and widening of the capsular space. Atrophy of some glomeruli was also noticed. With prolong exposure to heat changes in the proximal and distal convoluted tubules were prominent when compared with normal rats’ kidneys.

  8. Cross-fostering alters advertisement vocalizations of grasshopper mice (Onychomys): Evidence for the developmental stress hypothesis.

    Science.gov (United States)

    Pasch, Bret; Abbasi, Mustafa Z; Wilson, Macey; Zhao, Daniel; Searle, Jeremy B; Webster, Michael S; Rice, Aaron N

    2016-04-01

    Nutritional stress can have lasting impacts on the development of traits involved in vocal production. Cross-fostering experiments are often used to examine the propensity for vocal learning in a variety of taxa, but few studies assess the influence of malnourishment that can occur as a byproduct of this technique. In this study, we reciprocally cross-fostered sister taxa of voluble grasshopper mice (genus Onychomys) to explore their propensity for vocal learning. Vocalizations of Onychomys leucogaster did not differ between control and cross-fostered animals, but cross-fostered Onychomys arenicola produced vocalizations that were higher in frequency in a direction away from tutors. These same animals exhibited a transient reduction in body mass early in development, indicative of malnutrition. Our findings simultaneously refute vocal learning and support the developmental stress hypothesis to highlight the importance of early ontogeny on the production of vocalizations later in life. PMID:26873411

  9. Early and later life stress alter brain activity and sleep in rats.

    Directory of Open Access Journals (Sweden)

    Jelena Mrdalj

    Full Text Available Exposure to early life stress may profoundly influence the developing brain in lasting ways. Neuropsychiatric disorders associated with early life adversity may involve neural changes reflected in EEG power as a measure of brain activity and disturbed sleep. The main aim of the present study was for the first time to characterize possible changes in adult EEG power after postnatal maternal separation in rats. Furthermore, in the same animals, we investigated how EEG power and sleep architecture were affected after exposure to a chronic mild stress protocol. During postnatal day 2-14 male rats were exposed to either long maternal separation (180 min or brief maternal separation (10 min. Long maternally separated offspring showed a sleep-wake nonspecific reduction in adult EEG power at the frontal EEG derivation compared to the brief maternally separated group. The quality of slow wave sleep differed as the long maternally separated group showed lower delta power in the frontal-frontal EEG and a slower reduction of the sleep pressure. Exposure to chronic mild stress led to a lower EEG power in both groups. Chronic exposure to mild stressors affected sleep differently in the two groups of maternal separation. Long maternally separated offspring showed more total sleep time, more episodes of rapid eye movement sleep and higher percentage of non-rapid eye movement episodes ending in rapid eye movement sleep compared to brief maternal separation. Chronic stress affected similarly other sleep parameters and flattened the sleep homeostasis curves in all offspring. The results confirm that early environmental conditions modulate the brain functioning in a long-lasting way.

  10. Repeated neonatal handling with maternal separation permanently alters hippocampal GABAA receptors and behavioral stress responses

    OpenAIRE

    Hsu, Fu-Chun; Zhang, Guo-Jun; Raol, Yogendra Sinh H.; Valentino, Rita J.; Coulter, Douglas A.; Brooks-Kayal, Amy R.

    2003-01-01

    Increasing evidence suggests that postnatal events, such as handling or maternal separation, can produce long-term changes in brain function. These are often expressed as changes in the profile of endocrine or behavioral responses to stress. Changes in γ-aminobutyric acid type A receptors (GABARs), which mediate the majority of fast synaptic inhibition in adult brain, have been proposed as one potential mediator of these behavioral effects. In the current article, we use a combination of sing...

  11. Altered amygdala resting-state functional connectivity in post-traumatic stress disorder

    OpenAIRE

    Rabinak, Christine A.; Angstadt, Mike; Welsh, Robert C.; Kenndy, Amy E.; Lyubkin, Mark; Martis, Brian; Phan, K. Luan

    2011-01-01

    Post-traumatic stress disorder (PTSD) is often characterized by aberrant amygdala activation and functional abnormalities in corticolimbic circuitry, as elucidated by functional neuroimaging. These “activation” studies have primarily relied on tasks designed to induce region-specific, and task-dependent brain responses in limbic (e.g., amygdala) and paralimbic brain areas through the use of aversive evocative probes. It remains unknown if these corticolimbic circuit abnormalities exist at bas...

  12. Prenatal stress is a vulnerability factor for altered morphology and biological activity of microglia cells

    OpenAIRE

    Joanna Mika; Krzysztof Wędzony; Agnieszka Basta-Kaim

    2015-01-01

    Several lines of evidence suggest that the dysregulation of the immune system is an important factor in the development of depression. Microglia are the resident macrophages of the central nervous system and a key player in innate immunity of the brain. We hypothesized that prenatal stress (an animal model of depression) as a priming factor could affect microglial cells and might lead to depressive-like disturbances in adult male rat offspring. We investigated the behavioral changes (sucrose ...

  13. Alterations in empathic responding among women with posttraumatic stress disorder associated with childhood trauma

    OpenAIRE

    Parlar, Melissa; Frewen, Paul; Nazarov, Anthony; Oremus, Carolina; MacQueen, Glenda; Lanius, Ruth; McKinnon, Margaret C.

    2014-01-01

    Objective Although studies increasingly point toward problems with social cognition among individuals with posttraumatic stress disorder (PTSD), few studies have assessed empathic responding. The aim of the current study was to investigate empathic responding in women with PTSD related to childhood trauma, and the contribution of parental bonding to empathic abilities in this sample. Methods Participants with PTSD (n = 29) and sex- and age-matched healthy controls (n = 20) completed two self-...

  14. Alterations in the neural circuitry for emotion and attention associated with posttraumatic stress symptomatology

    OpenAIRE

    Hayes, Jasmeet Pannu; LaBar, Kevin S.; Petty, Christopher M.; McCarthy, Gregory; Morey, Rajendra A.

    2009-01-01

    Information processing models of posttraumatic stress disorder (PTSD) suggest that PTSD is characterized by preferential allocation of attentional resources to potentially threatening stimuli. However, few studies have examined the neural pattern underlying attention and emotion in association with PTSD symptomatology. In the present study, combat veterans with PTSD symptomatology engaged in an emotional oddball task while undergoing functional magnetic resonance imaging (fMRI). Veterans were...

  15. Developmental alterations and osmoregulatory physiology of a larval anuran under osmotic stress

    OpenAIRE

    Gómez-Mestre, Iván; Tejedo, Miguel; Ramayo E.; Estepa, J.

    2004-01-01

    Water salinity represents an environmental stress for many species. Amphibians are particularly sensitive because they are generally poor osmoregulators, and most species are completely absent from brackish and saline environments. We experimentally examined the effect of different salinity levels on larvae of the toad Bufo calamita L., a species that occupies freshwater ponds but can also breed in brackish ponds. Two independent experiments are reported here. In both experiments, tadpoles un...

  16. Significant alterations in reported clinical practice associated with increased oversight of organ transplant center performance.

    Science.gov (United States)

    Schold, Jesse D; Arrington, Charlotte J; Levine, Greg

    2010-09-01

    In the past several years, emphasis on quality metrics in the field of organ transplantation has increased significantly, largely because of the new conditions of participation issued by the Centers for Medicare and Medicaid Services. These regulations directly associate patients' outcomes and measured performance of centers with the distribution of public funding to institutions. Moreover, insurers and marketing ventures have used publicly available outcomes data from transplant centers for business decision making and advertisement purposes. We gave a 10-question survey to attendees of the Transplant Management Forum at the 2009 meeting of the United Network for Organ Sharing to ascertain how centers have responded to the increased oversight of performance. Of 63 responses, 55% indicated a low or near low performance rating at their center in the past 3 years. Respondents from low-performing centers were significantly more likely to indicate increased selection criteria for candidates (81% vs 38%, P = .001) and donors (77% vs 31%, P < .001) as well as alterations in clinical protocols (84% vs 52%, P = .007). Among respondents indicating lost insurance contracts (31%), these differences were also highly significant. Based on respondents' perceptions, outcomes of performance evaluations are associated with significant changes in clinical practice at transplant centers. The transplant community and policy makers should practice vigilance that performance evaluations and regulatory oversight do not inadvertently lead to diminished access to care among viable candidates or decreased transplant volume. PMID:20929114

  17. A novel method for performance improvement of optical CDMA system using alterable concatenated code

    Science.gov (United States)

    Qiu, Kun; Zhang, Chongfu

    2007-04-01

    A novel method using alterable concatenated code to pre-encode is proposed to reduce the impact of system impairment and multiple access interference (MAI) in optical code division multiple access (OCDMA) system, comprehensive comparisons between different concatenated code type and forward error correcting (FEC) scheme are studied by simulation. In the scheme, we apply concatenated coding to the embedded modulation scheme, and optical orthogonal code (OOC) is employed as address sequence code, an avalanche photodiode (APD) is selected as the system receiver. The bit error rate (BER) performance is derived taking into account the effect of some noises, dispersion power penalty and the MAI. From both theoretical analysis and numerical results, we can show that the proposed system has good performance at a BER of 10 -9 with a gain of 6.4 dB improvement achieved using the concatenated code as the pre-code, and this scheme permits implementation of a cost effective OCDMA system.

  18. Performance of diverse wheat genetic stocks under moisture stress condition

    International Nuclear Information System (INIS)

    This study was conducted to evaluate divergent wheat germplasm for their performance under drought and control conditions. The germplasm consists of wheat land races of Pakistan, advanced D-genome synthetic derivatives and high yielding varieties of Pakistan. This wide array of germplasm was selected to identify sources, which can be opted later by the wheat breeders while breeding for drought tolerance. The evaluation parameters involved some important physiochemical testing and morphological characteristics in the field under drought and control conditions. Based on these parameters, 13 wheat genotypes were selected on the basis of their best performance regarding morphological and physiological parameters. These genotypes exhibited higher yield under drought stress conditions and increased percentage of proline, sugar, SOD and protein content under laboratory conditions as compared to the susceptible genotypes. Correlation studies revealed that grains per spike (GPS) and thousand grain weight (TGW) had direct relationship with spike length (SL), proline and sugar content under both control and drought conditions. Thus, these parameters can be used as selection criteria for the identification of tolerant genotypes. (author)

  19. Neonatal handling of Amazon parrots alters the stress response and immune function.

    Science.gov (United States)

    Collette; Millam; Klasing; Wakenell

    2000-03-01

    The influence of neonatal handling on behavior and immune function was assessed in Orange-winged Amazon parrots (Amazona amazonica). Chicks (n=11) were gently handled daily from 25 days of age until 38 days post-fledging, while control chicks (n=9) were not handled. At 10 days post-fledging ( approximately 66 days of age), chicks were given tests to evaluate tameness (e.g., willingness to perch on an offered finger). They were then restrained for 10 min, either by being held while perching (handled group) or, because they would not perch, by being restrained in a towel (nonhandled group). Serum corticosterone levels were measured and immune status was assessed by: the delayed-type hypersensitivity (DTH) response to phytohemagglutinin-P (PH-P) injection; the humoral response to a killed Newcastle disease virus (NDV) challenge; and heterophil:lymphocyte ratio (H:L). Handled chicks were tamer by all measures of tameness. DTH was greater in nonhandled chicks (Pstressful. The greater DTH response of nonhandled chicks suggests that either their DTH response was enhanced by the acute stress of being restrained in a towel, and/or the DTH response of handled chicks was suppressed as a result of the repeated physiologic stress from handling during the neonatal period. In either event, handling produced marked differences in response to types of restraint that would be typically encountered in the husbandry of Amazons in captivity. PMID:10700631

  20. Altered baseline blood volume and the norepinephrine response to stress in humans

    Science.gov (United States)

    Vernikos, J.; Convertino, V. A.

    1992-01-01

    A hypothesis is proposed that a primary physiological purpose of the neural and endocrine response to stressors is the preservation of the blood volume/blood pressure relationship. Changes in blood volume caused by an adaptation to the environmental challenge serve to modulate the neural and endocrine responsiveness to stress. Relationships between changes in vascular volume, vasoconstriction, and norepinephrine (NE) responses during acute and chronic exposure to various stressors are examined. It is noted that the hypothesis is based on numerous observations rather than definitive cause-effect experiments and further investigation is required to prove it.

  1. Genetic alteration of anxiety and stress-like behavior in mice lacking CaMKIV

    OpenAIRE

    Kaang Bong-Kiun; Lee Yong-Seok; Ko Shanelle W; Shum Fanny WF; Zhuo Min

    2005-01-01

    Abstract Calcium-calmodulin-dependent protein kinase IV (CaMKIV) phosphorylates the major transcription factor cyclic AMP-response element binding protein (CREB), which plays a role in emotional behavior. Here, CaMKIV knockout mice (CaMKIV-/-) were tested in a battery of stress and anxiety-related behavioral tests, to determine if CaMKIV plays a role in emotional behavior. CaMKIV-/-exhibited a decrease in anxiety-like behavior in both the elevated plus maze and dark-light emergence tests when...

  2. Low-Shear modeled microgravity alters the Salmonella enterica serovar typhimurium stress response in an RpoS-independent manner

    Science.gov (United States)

    Wilson, James W.; Ott, C. Mark; Ramamurthy, Rajee; Porwollik, Steffen; McClelland, Michael; Pierson, Duane L.; Nickerson, Cheryl A.

    2002-01-01

    We have previously demonstrated that low-shear modeled microgravity (low-shear MMG) serves to enhance the virulence of a bacterial pathogen, Salmonella enterica serovar Typhimurium. The Salmonella response to low-shear MMG involves a signaling pathway that we have termed the low-shear MMG stimulon, though the identities of the low-shear MMG stimulon genes and regulatory factors are not known. RpoS is the primary sigma factor required for the expression of genes that are induced upon exposure to different environmental-stress signals and is essential for virulence in mice. Since low-shear MMG induces a Salmonella acid stress response and enhances Salmonella virulence, we reasoned that RpoS would be a likely regulator of the Salmonella low-shear MMG response. Our results demonstrate that low-shear MMG provides cross-resistance to several environmental stresses in both wild-type and isogenic rpoS mutant strains. Growth under low-shear MMG decreased the generation time of both strains in minimal medium and increased the ability of both strains to survive in J774 macrophages. Using DNA microarray analysis, we found no evidence of induction of the RpoS regulon by low-shear MMG but did find that other genes were altered in expression under these conditions in both the wild-type and rpoS mutant strains. Our results indicate that, under the conditions of these studies, RpoS is not required for transmission of the signal that induces the low-shear MMG stimulon. Moreover, our studies also indicate that low-shear MMG can be added to a short list of growth conditions that can serve to preadapt an rpoS mutant for resistance to multiple environmental stresses.

  3. TPP and TCEP induce oxidative stress and alter steroidogenesis in TM3 Leydig cells.

    Science.gov (United States)

    Chen, Guanliang; Zhang, Songbin; Jin, Yuanxiang; Wu, Yan; Liu, Ling; Qian, Haifeng; Fu, Zhengwei

    2015-11-01

    Effects of triphenyl phosphate (TPP) and tris-(2-chloroethyl) phosphate (TCEP) exposure on induction of oxidative stress and endocrine disruption were investigated in TM3 cells. After 24h exposure, cell growth declined and morphology changed in TPP and TCEP treated groups with high dosages. Significant increases in superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX) and glutathione S-transferase (GST) activities and their respective gene expressions in a dose-dependent and/or time-dependent manner in TPP or TCEP groups. Moreover, the expression of main genes related to testosterone (T) synthesis including cytochrome P450 cholesterol side-chain cleavage enzyme (P450scc), cytochrome P450 17α-hydroxysteroid dehydrogenase (P450-17α), 3β-hydroxysteroid dehydrogenase (3β-HSD) and 17β-hydroxysteroid dehydrogenase (17β-HSD) were dramatically reduced by TPP and TCEP treatments, especially with the high dosage for 24h. TPP and TCEP treatments for 24h caused significant decreases in T levels in the medium. Furthermore, co-treatments of hCG with TPP or TCEP could inhibit hCG-induced changes in the expression of P450scc, P450-17α and 17β-HSD and T levels. Taken together, TPP and TCEP could induce oxidative stress and endocrine disruption in TM3 cells. PMID:26049154

  4. Effect of Wall Shear Stress on Corrosion Inhibitor Film Performance

    Science.gov (United States)

    Canto Maya, Christian M.

    In oil and gas production, internal corrosion of pipelines causes the highest incidence of recurring failures. Ensuring the integrity of ageing pipeline infrastructure is an increasingly important requirement. One of the most widely applied methods to reduce internal corrosion rates is the continuous injection of chemicals in very small quantities, called corrosion inhibitors. These chemical substances form thin films at the pipeline internal surface that reduce the magnitude of the cathodic and/or anodic reactions. However, the efficacy of such corrosion inhibitor films can be reduced by different factors such as multiphase flow, due to enhanced shear stress and mass transfer effects, loss of inhibitor due to adsorption on other interfaces such as solid particles, bubbles and droplets entrained by the bulk phase, and due to chemical interaction with other incompatible substances present in the stream. The first part of the present project investigated the electrochemical behavior of two organic corrosion inhibitors (a TOFA/DETA imidazolinium, and an alkylbenzyl dimethyl ammonium chloride), with and without an inorganic salt (sodium thiosulfate), and the resulting enhancement. The second part of the work explored the performance of corrosion inhibitor under multiphase (gas/liquid, solid/liquid) flow. The effect of gas/liquid multiphase flow was investigated using small and large scale apparatus. The small scale tests were conducted using a glass cell and a submersed jet impingement attachment with three different hydrodynamic patterns (water jet, CO 2 bubbles impact, and water vapor cavitation). The large scale experiments were conducted applying different flow loops (hilly terrain and standing slug systems). Measurements of weight loss, linear polarization resistance (LPR), and adsorption mass (using an electrochemical quartz crystal microbalance, EQCM) were used to quantify the effect of wall shear stress on the performance and integrity of corrosion inhibitor

  5. Behavioral performance altering effects of MK-801 in zebrafish (Danio rerio).

    Science.gov (United States)

    Sison, Margarette; Gerlai, Robert

    2011-07-01

    MK-801, a non-competitive NMDA-R antagonist, has been utilized in the analysis of mammalian learning and memory. The zebrafish is a novel vertebrate study species that has been proposed for the analysis of the mechanisms of learning and memory. Although learning paradigms have been developed for this species, psychopharmacological characterization of its behavioral responses is rudimentary. Before one attempts the analysis of the effects of MK-801 on learning and memory in zebrafish, one needs to know whether this drug affects motor function, perception and/or motivation, factors that may influence performance in learning tasks. Here we conduct dose response analyses investigating the effects of 0, 2, 20 and 100 μM MK-801 administered 24h or 30 min before the behavioral test, or during the test. We analyze responses in the open tank to measure motor and posture patterns, in the light dark paradigm to evaluate visual perception, and in a group preference task to attempt to quantify motivation. Our results show a significant performance alteration only in the highest (100 μM) dose groups. These fish spent more time on the bottom of their tank, showed elevated Erratic movement, increased their clockwise and counterclockwise turning frequency, and reduced the time spent near a shoal stimulus, behavioral alterations that also depended upon the timing of drug administration. Thus, using the current delivery procedures and outbred zebrafish population, the highest dose that may not lead to significant performance deficits is 20 μM, a concentration we propose to use in a future learning study in zebrafish. PMID:21333690

  6. The Effects of Perceived Stress and Facebook on Accounting Students’ Academic Performance

    OpenAIRE

    Helen Gabre; Mr. Gaurav Kumar

    2012-01-01

    This paper has three objectives. First, we investigate the effects of perceived stress on the academic performance of accounting students. Second, we examine the association of Facebook use with perceived stress. Third, we investigate the effect of Facebook usage on accounting students’ academic performance. To measure the perceived stress we used the Perceived Stress Scale developed in the prior research for the shorter version and used it to collect data from accounting students at two univ...

  7. High performance thermal stress analysis on the earth simulator

    International Nuclear Information System (INIS)

    In this study, the thermal stress finite element analysis code optimized for the earth simulator was developed. A processor node of which of the earth simulator is the 8-way vector processor, and each processor can communicate using the message passing interface. Thus, there are two ways to parallelize the finite element method on the earth simulator. The first method is to assign one processor for one sub-domain, and the second method is to assign one node (=8 processors) for one sub-domain considering the shared memory type parallelization. Considering that the preconditioned conjugate gradient (PCG) method, which is one of the suitable linear equation solvers for the large-scale parallel finite element methods, shows the better convergence behavior if the number of domains is the smaller, we have determined to employ PCG and the hybrid parallelization, which is based on the shared and distributed memory type parallelization. It has been said that it is hard to obtain the good parallel or vector performance, since the finite element method is based on unstructured grids. In such situation, the reordering is inevitable to improve the computational performance [2]. In this study, we used three reordering methods, i.e. Reverse Cuthil-McKee (RCM), cyclic multicolor (CM) and diagonal jagged descending storage (DJDS)[3]. RCM provides the good convergence of the incomplete lower-upper (ILU) PCG, but causes the load imbalance. On the other hand, CM provides the good load balance, but worsens the convergence of ILU PCG if the vector length is so long. Therefore, we used the combined-method of RCM and CM. DJDS is the method to store the sparse matrices such that longer vector length can be obtained. For attaining the efficient inter-node parallelization, such partitioning methods as the recursive coordinate bisection (RCM) or MeTIS have been used. Computational performance of the practical large-scale engineering problems will be shown at the meeting. (author)

  8. Disturbance of wildlife by outdoor winter recreation: allostatic stress response and altered activity-energy budgets.

    Science.gov (United States)

    Arlettaz, Raphaël; Nusslé, Sébastien; Baltic, Marjana; Vogel, Peter; Palme, Rupert; Jenni-Eiermann, Susanne; Patthey, Patrick; Genoud, Michel

    2015-07-01

    Anthropogenic disturbance of wildlife is of growing conservation concern, but we lack comprehensive approaches of its multiple negative effects. We investigated several effects of disturbance by winter outdoor sports on free-ranging alpine Black Grouse by simultaneously measuring their physiological and behavioral responses. We experimentally flushed radio-tagged Black Grouse from their snow burrows, once a day, during several successive days, and quantified their stress hormone levels (corticosterone metabolites in feces [FCM] collected. from individual snow burrows). We also measured feeding time allocation (activity budgets reconstructed from radio-emitted signals) in response to anthropogenic disturbance. Finally, we estimated the related extra energy expenditure that may be incurred: based on activity budgets, energy expenditure was modeled from measures of metabolism obtained from captive birds subjected to different ambient temperatures. The pattern of FCM excretion indicated the existence of a funneling effect as predicted by the allostatic theory of stress: initial stress hormone concentrations showed a wide inter-individual variation, which decreased during experimental flushing. Individuals with low initial pre-flushing FCM values augmented their concentration, while individuals with high initial FCM values lowered it. Experimental disturbance resulted in an extension of feeding duration during the following evening foraging bout, confirming the prediction that Black Grouse must compensate for the extra energy expenditure elicited by human disturbance. Birds with low initial baseline FCM concentrations were those that spent more time foraging. These FCM excretion and foraging patterns suggest that birds with high initial FCM concentrations might have been experiencing a situation of allostatic overload. The energetic model provides quantitative estimates of extra energy expenditure. A longer exposure to ambient temperatures outside the shelter of snow

  9. Systematically Altering Bacterial SOS Activity under Stress Reveals Therapeutic Strategies for Potentiating Antibiotics.

    Science.gov (United States)

    Mo, Charlie Y; Manning, Sara A; Roggiani, Manuela; Culyba, Matthew J; Samuels, Amanda N; Sniegowski, Paul D; Goulian, Mark; Kohli, Rahul M

    2016-01-01

    The bacterial SOS response is a DNA damage repair network that is strongly implicated in both survival and acquired drug resistance under antimicrobial stress. The two SOS regulators, LexA and RecA, have therefore emerged as potential targets for adjuvant therapies aimed at combating resistance, although many open questions remain. For example, it is not well understood whether SOS hyperactivation is a viable therapeutic approach or whether LexA or RecA is a better target. Furthermore, it is important to determine which antimicrobials could serve as the best treatment partners with SOS-targeting adjuvants. Here we derived Escherichia coli strains that have mutations in either lexA or recA genes in order to cover the full spectrum of possible SOS activity levels. We then systematically analyzed a wide range of antimicrobials by comparing the mean inhibitory concentrations (MICs) and induced mutation rates for each drug-strain combination. We first show that significant changes in MICs are largely confined to DNA-damaging antibiotics, with strains containing a constitutively repressed SOS response impacted to a greater extent than hyperactivated strains. Second, antibiotic-induced mutation rates were suppressed when SOS activity was reduced, and this trend was observed across a wider spectrum of antibiotics. Finally, perturbing either LexA or RecA proved to be equally viable strategies for targeting the SOS response. Our work provides support for multiple adjuvant strategies, while also suggesting that the combination of an SOS inhibitor with a DNA-damaging antibiotic could offer the best potential for lowering MICs and decreasing acquired drug resistance. IMPORTANCE Our antibiotic arsenal is becoming depleted, in part, because bacteria have the ability to rapidly adapt and acquire resistance to our best agents. The SOS pathway, a widely conserved DNA damage stress response in bacteria, is activated by many antibiotics and has been shown to play central role in

  10. Systematically Altering Bacterial SOS Activity under Stress Reveals Therapeutic Strategies for Potentiating Antibiotics

    Science.gov (United States)

    Mo, Charlie Y.; Manning, Sara A.; Roggiani, Manuela; Culyba, Matthew J.; Samuels, Amanda N.; Sniegowski, Paul D.; Goulian, Mark

    2016-01-01

    ABSTRACT The bacterial SOS response is a DNA damage repair network that is strongly implicated in both survival and acquired drug resistance under antimicrobial stress. The two SOS regulators, LexA and RecA, have therefore emerged as potential targets for adjuvant therapies aimed at combating resistance, although many open questions remain. For example, it is not well understood whether SOS hyperactivation is a viable therapeutic approach or whether LexA or RecA is a better target. Furthermore, it is important to determine which antimicrobials could serve as the best treatment partners with SOS-targeting adjuvants. Here we derived Escherichia coli strains that have mutations in either lexA or recA genes in order to cover the full spectrum of possible SOS activity levels. We then systematically analyzed a wide range of antimicrobials by comparing the mean inhibitory concentrations (MICs) and induced mutation rates for each drug-strain combination. We first show that significant changes in MICs are largely confined to DNA-damaging antibiotics, with strains containing a constitutively repressed SOS response impacted to a greater extent than hyperactivated strains. Second, antibiotic-induced mutation rates were suppressed when SOS activity was reduced, and this trend was observed across a wider spectrum of antibiotics. Finally, perturbing either LexA or RecA proved to be equally viable strategies for targeting the SOS response. Our work provides support for multiple adjuvant strategies, while also suggesting that the combination of an SOS inhibitor with a DNA-damaging antibiotic could offer the best potential for lowering MICs and decreasing acquired drug resistance. IMPORTANCE Our antibiotic arsenal is becoming depleted, in part, because bacteria have the ability to rapidly adapt and acquire resistance to our best agents. The SOS pathway, a widely conserved DNA damage stress response in bacteria, is activated by many antibiotics and has been shown to play central role

  11. When Does Stress Help or Harm? The Effects of Stress Controllability and Subjective Stress Response on Stroop Performance

    OpenAIRE

    Roselinde Kaiser Henderson; Snyder, Hannah R.; Tina eGupta; Banich, Marie T

    2012-01-01

    The ability to engage in goal-directed behavior despite exposure to stress is critical to resilience. Questions of how stress can impair or improve behavioral functioning are important in diverse settings, from athletic competitions to academic testing. Previous research suggests that controllability is a key factor in the impact of stress on behavior: learning how to control stressors buffers people from the negative effects of stress on subsequent cognitively demanding tasks. In addition, r...

  12. ORGANIZATIONAL STRESS AND ITS IMPACT ON WORK PERFORMANCE

    OpenAIRE

    Costin Madalina - Adriana; Bucurean Mirela

    2011-01-01

    Nowadays, in times of economic crisis, most managers or entrepreneurs have to cope with a lot of new job challenges which can easily transform into stressors. Work related stress is of growing concern because it has significant economic implications for the organization. Even if some stress is a normal part of life, excessive stress can influence one's productivity, health and emotions and it has to be taken under control. When people lose confidence, they refuse to take responsibilities, the...

  13. Alterations in the hippocampal glycinergic system in an animal model of posttraumatic stress disorder.

    Science.gov (United States)

    Yamamoto, Shigeto; Morinobu, Shigeru; Iwamoto, Yasuyuki; Ueda, Yuto; Takei, Shiro; Fujita, Yosuke; Yamawaki, Shigeto

    2010-11-01

    Previous studies have demonstrated that rats subjected to single prolonged stress (SPS) exhibit posttraumatic stress disorder (PTSD)-like symptoms, such as enhanced contextual fear in response to trauma-related and trauma-unrelated events. Furthermore, we previously reported that upregulation of hippocampal glycine transporter 1 (GlyT-1) mRNA after context exposure could be the initial mechanism underlying impaired fear extinction in SPS rats. To clarify the involvement of the hippocampal glycinergic system in impaired fear extinction in SPS rats, we measured the time course of changes in the duration of freezing and the hippocampal levels of Gly-T1 mRNA using contextual fear conditioning (FC) and extinction training. We also used in vivo microdialysis to measure the concentration of extracellular glycine in the hippocampus during the time interval between FC and the first context exposure. SPS rats exhibited increased and sustained contextual fear responses. The enhanced contextual fear response in SPS rats was associated with a sustained increase in hippocampal levels of Gly-T1 mRNA after FC relative to sham rats, and by a decrease in the extracellular glycine concentration. GlyT-1 mRNA levels in rats that underwent repeated extinction training were significantly lower than in rats that did not undergo extinction training. These findings indicate that reduced activity of the hippocampal glycinergic system could be closely involved in impaired fear extinction in SPS rats, suggesting that activation of the glycinergic system by d-cycloserine or GlyT-1 inhibitors may ameliorate the impairment of fear extinction. PMID:20427053

  14. Effects of stress on auditors' organizational commitment, job satisfaction, and job performance

    Directory of Open Access Journals (Sweden)

    Abolghasem Masihabadi

    2015-09-01

    Full Text Available This study was designed to measure the effects of job stress on organizational commitment, job satisfaction, and job performance. A total of 170 questionnaires were distributed among auditors in the audit institutions in Tehran and Mashhad. To test the hypotheses, path analysis and structural equation and regression were employed. The results showed that the job stress had a negative effect on organizational commitment and job satisfaction and there was not a negative correlation between job stress and job performance. Job stress via organizational commitment and job satisfaction affected job performance negatively. Also, job stress had a negative impact on job satisfaction via organizational commitment.

  15. Stress and its impact on a performance in a job

    OpenAIRE

    Míková, Kateřina

    2012-01-01

    The subject of the bachelor work is an analysis of the influence of stress on the productivity at work. The introductory chapter of the theoretical part of the bachelor work is dedicated to a stress as a term, including the definition of types of stress and its affect on human or segmentation of stressors according several aspects. The second chapter is focused on coping with the stress including an indicating of the symptoms and its causes or addictions between type of personality and heart ...

  16. Physiological and molecular alterations in plants exposed to high [CO2] under phosphorus stress.

    Science.gov (United States)

    Pandey, Renu; Zinta, Gaurav; AbdElgawad, Hamada; Ahmad, Altaf; Jain, Vanita; Janssens, Ivan A

    2015-01-01

    Atmospheric [CO2] has increased substantially in recent decades and will continue to do so, whereas the availability of phosphorus (P) is limited and unlikely to increase in the future. P is a non-renewable resource, and it is essential to every form of life. P is a key plant nutrient controlling the responsiveness of photosynthesis to [CO2]. Increases in [CO2] typically results in increased biomass through stimulation of net photosynthesis, and hence enhance the demand for P uptake. However, most soils contain low concentrations of available P. Therefore, low P is one of the major growth-limiting factors for plants in many agricultural and natural ecosystems. The adaptive responses of plants to [CO2] and P availability encompass alterations at morphological, physiological, biochemical and molecular levels. In general low P reduces growth, whereas high [CO2] enhances it particularly in C3 plants. Photosynthetic capacity is often enhanced under high [CO2] with sufficient P supply through modulation of enzyme activities involved in carbon fixation such as ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco). However, high [CO2] with low P availability results in enhanced dry matter partitioning towards roots. Alterations in below-ground processes including root morphology, exudation and mycorrhizal association are influenced by [CO2] and P availability. Under high P availability, elevated [CO2] improves the uptake of P from soil. In contrast, under low P availability, high [CO2] mainly improves the efficiency with which plants produce biomass per unit P. At molecular level, the spatio-temporal regulation of genes involved in plant adaptation to low P and high [CO2] has been studied individually in various plant species. Genome-wide expression profiling of high [CO2] grown plants revealed hormonal regulation of biomass accumulation through complex transcriptional networks. Similarly, differential transcriptional regulatory networks are involved in P

  17. Metabolomic alterations in human cancer cells by vitamin C-induced oxidative stress.

    Science.gov (United States)

    Uetaki, Megumi; Tabata, Sho; Nakasuka, Fumie; Soga, Tomoyoshi; Tomita, Masaru

    2015-01-01

    Intravenous administration of high-dose vitamin C has recently attracted attention as a cancer therapy. High-dose vitamin C induces pro-oxidant effects and selectively kills cancer cells. However, the anticancer mechanisms of vitamin C are not fully understood. Here, we analyzed metabolic changes induced by vitamin C in MCF7 human breast adenocarcinoma and HT29 human colon cancer cells using capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS). The metabolomic profiles of both cell lines were dramatically altered after exposure to cytotoxic concentrations of vitamin C. Levels of upstream metabolites in the glycolysis pathway and tricarboxylic acid (TCA) cycle were increased in both cell lines following treatment with vitamin C, while adenosine triphosphate (ATP) levels and adenylate energy charges were decreased concentration-dependently. Treatment with N-acetyl cysteine (NAC) and reduced glutathione (GSH) significantly inhibited vitamin C-induced cytotoxicity in MCF7 cells. NAC also suppressed vitamin C-dependent metabolic changes, and NAD treatment prevented vitamin C-induced cell death. Collectively, our data suggests that vitamin C inhibited energy metabolism through NAD depletion, thereby inducing cancer cell death. PMID:26350063

  18. Skeletal muscle alterations and exercise performance decrease in erythropoietin-deficient mice: a comparative study

    Directory of Open Access Journals (Sweden)

    Mille-Hamard Laurence

    2012-06-01

    Full Text Available Abstract Background Erythropoietin (EPO is known to improve exercise performance by increasing oxygen blood transport and thus inducing a higher maximum oxygen uptake (VO2max. Furthermore, treatment with (or overexpression of EPO induces protective effects in several tissues, including the myocardium. However, it is not known whether EPO exerts this protective effect when present at physiological levels. Given that EPO receptors have been identified in skeletal muscle, we hypothesized that EPO may have a direct, protective effect on this tissue. Thus, the objectives of the present study were to confirm a decrease in exercise performance and highlight muscle transcriptome alterations in a murine EPO functional knock-out model (the EPO-d mouse. Methods We determined VO2max peak velocity and critical speed in exhaustive runs in 17 mice (9 EPO-d animals and 8 inbred controls, using treadmill enclosed in a metabolic chamber. Mice were sacrificed 24h after a last exhaustive treadmill exercise at critical speed. The tibialis anterior and soleus muscles were removed and total RNA was extracted for microarray gene expression analysis. Results The EPO-d mice’s hematocrit was about 50% lower than that of controls (p  1.4 and 115 were strongly down-regulated (normalized ratio  Conclusions Our results showed that the lack of functional EPO induced a decrease in the aerobic exercise capacity. This decrease was correlated with the hematocrit and reflecting poor oxygen supply to the muscles. The observed alterations in the muscle transcriptome suggest that physiological concentrations of EPO exert both direct and indirect muscle-protecting effects during exercise. However, the signaling pathway involved in these protective effects remains to be described in detail.

  19. High aggression in rats is associated with elevated stress, anxiety-like behavior, and altered catecholamine content in the brain

    OpenAIRE

    Patki, Gaurav; Atrooz, Fatin; Alkadhi, Isam; Solanki, Naimesh; Salim, Samina

    2014-01-01

    The social defeat paradigm involves aggressive encounters between Long-Evans (LE) (resident) and Sprague-Dawley (SD) (intruder) rats. Successful application of chronic social defeat stress in SD rats is dependent upon selection of highly aggressive LE rats. Half of the LE rats screened for aggression did not meet the criterion for aggression (LE rats performing a defeat, characterized by the intruder surrendering or acquiring a supine position for at least 3 sec). The observation of the diffe...

  20. Alterations in cancer cell mechanical properties after fluid shear stress exposure: a micropipette aspiration study

    Directory of Open Access Journals (Sweden)

    Chivukula VK

    2015-01-01

    Full Text Available Venkat Keshav Chivukula,1 Benjamin L Krog,1,2 Jones T Nauseef,2 Michael D Henry,2 Sarah C Vigmostad1 1Department of Biomedical Engineering, 2Department of Molecular Physiology and Biophysics, Holden Comprehensive Cancer Center, University of Iowa, Seamans Center for the Engineering Arts and Sciences, Iowa City, IA, USA Abstract: Over 90% of cancer deaths result not from primary tumor development, but from metastatic tumors that arise after cancer cells circulate to distal sites via the circulatory system. While it is known that metastasis is an inefficient process, the effect of hemodynamic parameters such as fluid shear stress (FSS on the viability and efficacy of metastasis is not well understood. Recent work has shown that select cancer cells may be able to survive and possibly even adapt to FSS in vitro. The current research seeks to characterize the effect of FSS on the mechanical properties of suspended cancer cells in vitro. Nontransformed prostate epithelial cells (PrEC LH and transformed prostate cancer cells (PC-3 were used in this study. The Young's modulus was determined using micropipette aspiration. We examined cells in suspension but not exposed to FSS (unsheared and immediately after exposure to high (6,400 dyn/cm2 and low (510 dyn/cm2 FSS. The PrEC LH cells were ~140% stiffer than the PC-3 cells not exposed to FSS. Post-FSS exposure, there was an increase of ~77% in Young's modulus after exposure to high FSS and a ~47% increase in Young's modulus after exposure to low FSS for the PC-3 cells. There was no significant change in the Young's modulus of PrEC LH cells post-FSS exposure. Our findings indicate that cancer cells adapt to FSS, with an increased Young's modulus being one of the adaptive responses, and that this adaptation is specific only to PC-3 cells and is not seen in PrEC LH cells. Moreover, this adaptation appears to be graded in response to the magnitude of FSS experienced by the cancer cells. This is the first study

  1. The impact of initiation: Early onset marijuana smokers demonstrate altered Stroop performance and brain activation

    Directory of Open Access Journals (Sweden)

    K.A. Sagar

    2015-12-01

    Full Text Available Marijuana (MJ use is on the rise, particularly among teens and emerging adults. This poses serious public health concern, given the potential deleterious effects of MJ on the developing brain. We examined 50 chronic MJ smokers divided into early onset (regular MJ use prior to age 16; n = 24 and late onset (age 16 or later; n = 26, and 34 healthy control participants (HCs. All completed a modified Stroop Color Word Test during fMRI. Results demonstrated that MJ smokers exhibited significantly poorer performance on the Interference subtest of the Stroop, as well as altered patterns of activation in the cingulate cortex relative to HCs. Further, early onset MJ smokers exhibited significantly poorer performance relative to both HCs and late onset smokers. Additionally, earlier age of MJ onset as well as increased frequency and magnitude (grams/week of MJ use were predictive of poorer Stroop performance. fMRI results revealed that while late onset smokers demonstrated a more similar pattern of activation to the control group, a different pattern was evident in the early onset group. These findings underscore the importance of assessing age of onset and patterns of MJ use and support the need for widespread education and intervention efforts among youth.

  2. Functional Metabolomics Uncovers Metabolic Alterations Associated to Severe Oxidative Stress in MCF7 Breast Cancer Cells Exposed to Ascididemin

    Directory of Open Access Journals (Sweden)

    Daniel Morvan

    2013-10-01

    Full Text Available Marine natural products are a source of promising agents for cancer treatment. However, there is a need to improve the evaluation of their mechanism of action in tumors. Metabolomics of the response to anti-tumor agents is a tool to reveal candidate biomarkers and metabolic targets. We used two-dimensional high-resolution magic angle spinning proton-NMR spectroscopy-based metabolomics to investigate the response of MCF7 breast cancer cells to ascididemin, a marine alkaloid and lead molecule for anti-cancer treatment. Ascididemin induced severe oxidative stress and apoptosis within 48 h of exposure. Thirty-three metabolites were quantified. Metabolic response involved downregulation of glycolysis and the tricarboxylic acid cycle, and phospholipid metabolism alterations. Candidate metabolic biomarkers of the response of breast cancer cells to ascididemin were proposed including citrate, gluconate, polyunsaturated fatty acids, glycerophospho-choline and -ethanolamine. In addition, candidate metabolic targets were identified. Overall, the response to Asc could be related to severe oxidative stress and anti-inflammatory effects.

  3. Disease-associated polymorphisms in ERAP1 do not alter endoplasmic reticulum stress in patients with ankylosing spondylitis.

    Science.gov (United States)

    Kenna, T J; Lau, M C; Keith, P; Ciccia, F; Costello, M-E; Bradbury, L; Low, P-L; Agrawal, N; Triolo, G; Alessandro, R; Robinson, P C; Thomas, G P; Brown, M A

    2015-01-01

    The mechanism by which human leukocyte antigen B27 (HLA-B27) contributes to ankylosing spondylitis (AS) remains unclear. Genetic studies demonstrate that association with and interaction between polymorphisms of endoplasmic reticulum aminopeptidase 1 (ERAP1) and HLA-B27 influence the risk of AS. It has been hypothesised that ERAP1-mediated HLA-B27 misfolding increases endoplasmic reticulum (ER) stress, driving an interleukin (IL) 23-dependent, pro-inflammatory immune response. We tested the hypothesis that AS-risk ERAP1 variants increase ER-stress and concomitant pro-inflammatory cytokine production in HLA-B27(+) but not HLA-B27(-) AS patients or controls. Forty-nine AS cases and 22 healthy controls were grouped according to HLA-B27 status and AS-associated ERAP1 rs30187 genotypes: HLA-B27(+)ERAP1(risk), HLA-B27(+)ERAP1(protective), HLA-B27(-)ERAP1(risk) and HLA-B27(-)ERAP1(protective). Expression levels of ER-stress markers GRP78 (8 kDa glucose-regulated protein), CHOP (C/EBP-homologous protein) and inflammatory cytokines were determined in peripheral blood mononuclear cell and ileal biopsies. We found no differences in ER-stress gene expression between HLA-B27(+) and HLA-B27(-) cases or healthy controls, or between cases or controls stratified by carriage of ERAP1 risk or protective alleles in the presence or absence of HLA-B27. No differences were observed between expression of IL17A or TNF (tumour necrosis factor) in HLA-B27(+)ERAP1(risk), HLA-B27(+)ERAP1(protective) and HLA-B27(-)ERAP1(protective) cases. These data demonstrate that aberrant ERAP1 activity and HLA-B27 carriage does not alter ER-stress levels in AS, suggesting that ERAP1 and HLA-B27 may influence disease susceptibility through other mechanisms. PMID:25354578

  4. Dietary pollutants induce oxidative stress, altering maternal antioxidant provisioning and reproductive output in the temperate sea urchin Evechinus chloroticus.

    Science.gov (United States)

    Lister, Kathryn N; Lamare, Miles D; Burritt, David J

    2016-08-01

    Evidence is growing to suggest that the capacity to withstand oxidative stress may play an important role in shaping life-history trade-offs, although little is known on the relationship in broadcast spawning marine invertebrates. In this group, variation in gamete quantity and quality are important drivers of offspring survival and successful recruitment. Therefore the provisioning of eggs with antioxidants may be an important driver of life history strategies because they play a critical role in preventing damage from reactive oxygen species to macromolecules. In this study, a suite of oxidative stress biomarkers was measured in the gonads and eggs of the sea urchin Evechinus chloroticus exposed to polycyclic aromatic hydrocarbons (PAHs). Links between oxidative stress markers and core components of fitness including fecundity, gamete quality and maternal transfer of antioxidants were assessed. Experimental induction of oxidative stress was achieved via exposure to a mix of four PAHs over a 21-day period. In PAH exposed individuals, we observed a significant upregulation of the antioxidant defence and detoxification enzymes SOD, CAT, GR, GPx and GST, as well as a greater pool of the non-enzymatic antioxidant glutathione in gonad tissue and eggs. In contrast, glutathione redox status was not affected by PAH exposure, with the percentage of reduced glutathione remaining at approximately 80% in both gonad tissue and released eggs. PAH-exposed adults experienced greater than three- and five-fold increases in oxidative protein and lipid damage, respectively, in gonad tissue. In contrast, eggs maintained low levels of damage, not differing from baseline levels found in eggs released from PAH-naïve mothers. PAH exposure also resulted in a 2-fold reduction in fecundity of reproductively mature females but no significant alteration to egg diameter. Although PAH-exposed females released fewer eggs, successful fertilisation of those eggs was slightly enhanced with average

  5. Stress and inflammatory gene networks in bovine liver are altered by plane of dietary energy during late pregnancy.

    Science.gov (United States)

    Khan, M Jawad; Jacometo, Carolina B; Riboni, Mario Vailati; Trevisi, Erminio; Graugnard, Daniel E; Corrêa, Marcio N; Loor, Juan J

    2015-09-01

    fed the lower-energy diet experienced a gradual increase in the inflammatory response. The lack of differences between groups in voluntary feed intake and lactation capacity suggests that nutritional management prepartum triggers different mechanisms that affect ER and oxidative stress along with inflammation. Although no clinical disorders were detected, these alterations expose animals to the development of immuno-metabolic disorders. PMID:25939883

  6. Subchronic and mild social defeat stress alter mouse nest building behavior.

    Science.gov (United States)

    Otabi, Hikari; Goto, Tatsuhiko; Okayama, Tsuyoshi; Kohari, Daisuke; Toyoda, Atsushi

    2016-01-01

    Behavioral and physiological evaluations of animal models of depression are essential to thoroughly understand the mechanisms of depression in humans. Various models have been developed and characterized, and the socially defeated mouse has been widely used for studying depression. Here, we developed and characterized a mouse model of social aversion using a subchronic and mild social defeat stress (sCSDS) paradigm. Compared to control mice, sCSDS mice showed significantly increased body weight gain, water intake, and social aversion to dominant mice on the social interaction test. We observed nest building behavior in sCSDS mice using the pressed cotton as a nest material. Although sCSDS mice eventually successfully built nests, the onset of nest building was severely delayed compared to control mice. The underlying mechanism of this significant delay in nest building by sCSDS mice is unclear. However, our results demonstrate that nest building evaluation is a simple and useful assay for understanding behavior in socially defeated mice and screening drugs such as antidepressants. PMID:26524409

  7. Chromium stress induced alterations in biochemical and enzyme metabolism in aquatic and terrestrial plants.

    Science.gov (United States)

    Ganesh, K Sankar; Baskaran, L; Rajasekaran, S; Sumathi, K; Chidambaram, A L A; Sundaramoorthy, P

    2008-06-01

    Water is seriously polluted by the discharge of various industrial wastewater containing heavy metals. Among them, chromium is considered to be toxic to living organisms and it is released mostly from tanneries. The chromium-contaminated water is discharged into nearby water bodies and it affects both aquatic and terrestrial plants. So the present experiment was conducted with an aquatic plant, water lettuce (Pistia stratiotes L.) and a terrestrial plant soybean (Glycine max L. Merr.). They were treated with different concentrations (0, 5, 10, 25, 50, 100 and 200mg/L) of potassium dichromate solution. The biochemical parameters such as total chlorophyll, carotenoid, protein and amino acid content and the enzymatic activities like catalase and peroxidase were estimated. The accumulation of chromium was also analysed in both the plants. All the biochemical contents and enzyme activities of water lettuce and soybean seedlings showed a great variation with respect to the increase in chromium concentrations. The accumulation of chromium increased gradually with the increase of chromium concentrations. Total inhibition of all the parameters were observed at 300 mg/L chromium concentration. The terrestrial plant soybean was sensitive than the aquatic plant water lettuce towards chromium stress. PMID:18206355

  8. Evaluation of proteome alterations induced by cadmium stress in sunflower (Helianthus annuus L.) cultures.

    Science.gov (United States)

    Lopes Júnior, Cícero Alves; Barbosa, Herbert de Sousa; Moretto Galazzi, Rodrigo; Ferreira Koolen, Hector Henrique; Gozzo, Fábio Cesar; Arruda, Marco Aurélio Zezzi

    2015-09-01

    The present study evaluates, at a proteomic level, changes in protein abundance in sunflower leaves in the absence or presence (at 50 or 700mg) of cadmium (as CdCl2). At the end of the cultivation period (45 days), proteins are extracted from leaves with phenol, separated by two-dimensional difference gel electrophoresis (2-D DIGE), and excised from the gels. The differential protein abundances (for proteins differing by more than 1.8 fold, which corresponds to 90% variation) are characterized using nESI-LC-MS/MS. The protein content decreases by approximately 41% in plants treated with 700mg Cd compared with control plants. By comparing all groups of plants evaluated in this study (Control vs. Cd-lower, Control vs. Cd-higher and Cd-lower vs. Cd-higher), 39 proteins are found differential and 18 accurately identified; the control vs. Cd-higher treatment is that presenting the most differential proteins. From identified proteins, those involved in energy and disease/defense (including stress), are the ribulose bisphosphate carboxylase large chain, transketolase, and heat shock proteins are the most differential abundant proteins. Thus, at the present study, photosynthesis is the main process affected by Cd in sunflowers, although these plants are highly tolerant to Cd. PMID:26004357

  9. Factors affecting Safety Performance in Repair, Maintenance, Alteration, and Addition (RMAA Projects

    Directory of Open Access Journals (Sweden)

    Adnan Enshassi

    2014-11-01

    Full Text Available Repair, Maintenance, Alteration and Addition (RMAA works are playing an increasingly important role in developing countries. The accidents and fatalities records of RMAA sector in Gaza Strip have been alarmingly high; however, research in the RMAA sector remains limited. Safety of RMAA works has long been neglected because the project sizes of RMAA are small and only last for a short period of time, which make the working environment of RMAA works more difficult to control than new building works. The aim of this paper is to identify, valuate and rank the most important factors that affect safety performance and the most important causes of fatal accidents in RMAA projects. A questionnaire survey was used in this study. The results revealed that poor safety awareness of managers in maintenance firms and lack of training of RMAA workers for handling multi-tasks were the most important factors that affecting safety performance of RMAA works. The results showed that ineffectiveness of lack of training and certification of competence; immature corporate systems of firms which does not care with safety and health through RMAA works, and lack of leadership from government as a key client are the most significant causes of construction fatal accidents of RMAA projects. The results also indicated that the macro level factor is the most important category that causes fatal accidents in RMAA works. It is recommended to enhance the awareness of construction firms, project managers and workers regarding the importance of safety performance in repair and maintenance works and strengthen site monitoring and supervision system in construction firms. Safety training courses should be organized for workers and project managers in order to improve their safety culture and competence regarding safety performance through repair and maintenance works. Furthermore the RMAA subcontractors should be selected according to their good records of safety performance.

  10. AN OVERVIEW OF THE EFFECTS OF JOB STRESS ON EMPLOYEES PERFORMANCE IN NIGERIA TERTIARY HOSPITALS

    OpenAIRE

    Adetayo Joshua Olusegun, Ajani John Oluwasayo, Olabisi Olawoyim

    2015-01-01

    This research work was carried out to appraise Job stress and performance of employee in an organization. One of the organizational outcomes that are affected by occupational stress is performance. Employees’ performance can be viewed as an activity in which an individual is able to accomplish the task assigned to his/her successfully, subject to the normal constraints of reasonable utilization of the available resources. The focus of this study is to appraise the cause of stress, the effect ...

  11. Personal and Job Related Predictors of Teacher Stress and Job Performance among School Teachers

    OpenAIRE

    Rubina Hanif; Sadaf Tariq; Masood Nadeem

    2011-01-01

    The present study was conducted to find out role of personal and job related variables in teacher stress and job performance of school teachers. Furthermore, levels and sources of stress and their relationship with job performance among teachers were also explored. The measures used in this study were indigenously developed i.e., Teacher Stress Inventory (TSI-Urdu), Teachers Job Performance Scale and personal and job related Information sheet. Two independent samples were selected from Govern...

  12. Relationship Between Organizational Climate, Job Stress And Job Performance Officer At State Education Department

    OpenAIRE

    Turiman Suandi; Ismi Arif Ismail; Zulfadli Othman

    2014-01-01

    This research aims at finding out the relationship between Organizational Climate, job stress and job performance among State Education Department (JPN) officers . The focus of the research is to determeane the job performance of state education department officers, level of job stress among the officers, level of connection between organizational climate with job stress of State Education Department officers, looking at the difference in level of performance according to demographic factors ...

  13. Altered olfactory processing of stress-related body odors and artificial odors in patients with panic disorder.

    Directory of Open Access Journals (Sweden)

    Gloria-Beatrice Wintermann

    Full Text Available BACKGROUND: Patients with Panic Disorder (PD direct their attention towards potential threat, followed by panic attacks, and increased sweat production. Onés own anxiety sweat odor influences the attentional focus, and discrimination of threat or non-threat. Since olfactory projection areas overlap with neuronal areas of a panic-specific fear network, the present study investigated the neuronal processing of odors in general and of stress-related sweat odors in particular in patients with PD. METHODS: A sample of 13 patients with PD with/ without agoraphobia and 13 age- and gender-matched healthy controls underwent an fMRI investigation during olfactory stimulation with their stress-related sweat odors (TSST, ergometry as well as artificial odors (peach, artificial sweat as non-fearful non-body odors. PRINCIPAL FINDINGS: The two groups did not differ with respect to their olfactory identification ability. Independent of the kind of odor, the patients with PD showed activations in fronto-cortical areas in contrast to the healthy controls who showed activations in olfaction-related areas such as the amygdalae and the hippocampus. For artificial odors, the patients with PD showed a decreased neuronal activation of the thalamus, the posterior cingulate cortex and the anterior cingulate cortex. Under the presentation of sweat odor caused by ergometric exercise, the patients with PD showed an increased activation in the superior temporal gyrus, the supramarginal gyrus, and the cingulate cortex which was positively correlated with the severity of the psychopathology. For the sweat odor from the anxiety condition, the patients with PD showed an increased activation in the gyrus frontalis inferior, which was positively correlated with the severity of the psychopathology. CONCLUSIONS: The results suggest altered neuronal processing of olfactory stimuli in PD. Both artificial odors and stress-related body odors activate specific parts of a fear

  14. Low-power millimeter wave radiations do not alter stress-sensitive gene expression of chaperone proteins.

    Science.gov (United States)

    Zhadobov, M; Sauleau, R; Le Coq, L; Debure, L; Thouroude, D; Michel, D; Le Dréan, Y

    2007-04-01

    This article reports experimental results on the influence of low-power millimeter wave (MMW) radiation at 60 GHz on a set of stress-sensitive gene expression of molecular chaperones, namely clusterin (CLU) and HSP70, in a human brain cell line. Selection of the exposure frequency is determined by its near-future applications for the new broadband civil wireless communication systems including wireless local area networks (WLAN) for domestic and professional uses. Frequencies around 60 GHz are strongly attenuated in the earth's atmosphere and such radiations represent a new environmental factor. An exposure system operating in V-band (50-75 GHz) was developed for cell exposure. U-251 MG glial cell line was sham-exposed or exposed to MMW radiation for different durations (1-33 h) and two different power densities (5.4 microW/cm(2) or 0.54 mW/cm(2)). As gene expression is a multiple-step process, we analyzed chaperone proteins induction at different levels. First, using luciferase reporter gene, we investigated potential effect of MMWs on the activation of transcription factors (TFs) and gene promoter activity. Next, using RT-PCR and Western blot assays, we verified whether MMW exposure could alter RNA accumulation, translation, or protein stability. Experimental data demonstrated the absence of significant modifications in gene transcription, mRNA, and protein amount for the considered stress-sensitive genes for the exposure durations and power densities investigated. The main results of this study suggest that low-power 60 GHz radiation does not modify stress-sensitive gene expression of chaperone proteins. PMID:17080454

  15. Implications of altered glutathione metabolism in aspirin-induced oxidative stress and mitochondrial dysfunction in HepG2 cells.

    Directory of Open Access Journals (Sweden)

    Haider Raza

    Full Text Available We have previously reported that acetylsalicylic acid (aspirin, ASA induces cell cycle arrest, oxidative stress and mitochondrial dysfunction in HepG2 cells. In the present study, we have further elucidated that altered glutathione (GSH-redox metabolism in HepG2 cells play a critical role in ASA-induced cytotoxicity. Using selected doses and time point for ASA toxicity, we have demonstrated that when GSH synthesis is inhibited in HepG2 cells by buthionine sulfoximine (BSO, prior to ASA treatment, cytotoxicity of the drug is augmented. On the other hand, when GSH-depleted cells were treated with N-acetyl cysteine (NAC, cytotoxicity/apoptosis caused by ASA was attenuated with a significant recovery in oxidative stress, GSH homeostasis, DNA fragmentation and some of the mitochondrial functions. NAC treatment, however, had no significant effects on the drug-induced inhibition of mitochondrial aconitase activity and ATP synthesis in GSH-depleted cells. Our results have confirmed that aspirin increases apoptosis by increased reactive oxygen species production, loss of mitochondrial membrane potential and inhibition of mitochondrial respiratory functions. These effects were further amplified when GSH-depleted cells were treated with ASA. We have also shown that some of the effects of aspirin might be associated with reduced GSH homeostasis, as treatment of cells with NAC attenuated the effects of BSO and aspirin. Our results strongly suggest that GSH dependent redox homeostasis in HepG2 cells is critical in preserving mitochondrial functions and preventing oxidative stress associated complications caused by aspirin treatment.

  16. Subclinical Alterations of Cardiac Mechanics Present Early in the Course of Pediatric Type 1 Diabetes Mellitus: A Prospective Blinded Speckle Tracking Stress Echocardiography Study

    Science.gov (United States)

    Hensel, Kai O.; Grimmer, Franziska; Roskopf, Markus; Jenke, Andreas C.; Wirth, Stefan; Heusch, Andreas

    2016-01-01

    Diabetic cardiomyopathy substantially accounts for mortality in diabetes mellitus. The pathophysiological mechanism underlying diabetes-associated nonischemic heart failure is poorly understood and clinical data on myocardial mechanics in early stages of diabetes are lacking. In this study we utilize speckle tracking echocardiography combined with physical stress testing in order to evaluate whether left ventricular (LV) myocardial performance is altered early in the course of uncomplicated type 1 diabetes mellitus (T1DM). 40 consecutive asymptomatic normotensive children and adolescents with T1DM (mean age 11.5 ± 3.1 years and mean disease duration 4.3 ± 3.5 years) and 44 age- and gender-matched healthy controls were assessed using conventional and quantitative echocardiography (strain and strain rate) during bicycle ergometer stress testing. Strikingly, T1DM patients had increased LV longitudinal (p = 0.019) and circumferential (p = 0.016) strain rate both at rest and during exercise (p = 0.021). This was more pronounced in T1DM patients with a longer disease duration (p = 0.038). T1DM patients with serum HbA1c > 9% showed impaired longitudinal (p = 0.008) and circumferential strain (p = 0.005) and a reduced E/A-ratio (p = 0.018). In conclusion, asymptomatic T1DM patients have signs of hyperdynamic LV contractility early in the course of the disease. Moreover, poor glycemic control is associated with early subclinical LV systolic and diastolic impairment. PMID:26839891

  17. Subclinical Alterations of Cardiac Mechanics Present Early in the Course of Pediatric Type 1 Diabetes Mellitus: A Prospective Blinded Speckle Tracking Stress Echocardiography Study

    Directory of Open Access Journals (Sweden)

    Kai O. Hensel

    2016-01-01

    Full Text Available Diabetic cardiomyopathy substantially accounts for mortality in diabetes mellitus. The pathophysiological mechanism underlying diabetes-associated nonischemic heart failure is poorly understood and clinical data on myocardial mechanics in early stages of diabetes are lacking. In this study we utilize speckle tracking echocardiography combined with physical stress testing in order to evaluate whether left ventricular (LV myocardial performance is altered early in the course of uncomplicated type 1 diabetes mellitus (T1DM. 40 consecutive asymptomatic normotensive children and adolescents with T1DM (mean age 11.5±3.1 years and mean disease duration 4.3±3.5 years and 44 age- and gender-matched healthy controls were assessed using conventional and quantitative echocardiography (strain and strain rate during bicycle ergometer stress testing. Strikingly, T1DM patients had increased LV longitudinal (p=0.019 and circumferential (p=0.016 strain rate both at rest and during exercise (p=0.021. This was more pronounced in T1DM patients with a longer disease duration (p=0.038. T1DM patients with serum HbA1c>9% showed impaired longitudinal (p=0.008 and circumferential strain (p=0.005 and a reduced E/A-ratio (p=0.018. In conclusion, asymptomatic T1DM patients have signs of hyperdynamic LV contractility early in the course of the disease. Moreover, poor glycemic control is associated with early subclinical LV systolic and diastolic impairment.

  18. The Relationship of Academic Stress with Aggression, Depression and Academic Performance of College Students in Iran

    Science.gov (United States)

    Khanehkeshi, Ali; Basavarajappa

    2011-01-01

    This paper investigates the relationship of academic stress with aggression, depression and academic performance of college students. Using a random sampling technique, 60 students consist of boys and girls were selected as students having academic stress. The scale for assessing academic stress (Sinha, Sharma and Mahendra, 2001); the Buss-Perry…

  19. Alterations in the Masseter Muscle and Plasma IL-6 Level Following Experimentally Induced Occlusal Interference and Chronic Stress – A Study in Rats

    OpenAIRE

    Simonić-Kocijan, Sunčana; Uhač, Ivone; Tariba, Petra; Fugošić, Vesna; Kovačević Pavičić, Daniela; Lajnert, Vlatka; Braut, Vedrana

    2012-01-01

    This study was undertaken to examine the alteration of masseter and plasma interleukin-6 after inducing occlusal interference and chronic stress. Male Wistar rats were submitted to chronic stress procedure, exposed to occlusal interference, or exposed to both mentioned procedures. Whole blood and masseter tissue were collected to determine interleukin-6 level, measured by means of ELISA. Masseter pain was evaluated using the orofacial formalin test. Masseter interleukin- 6 level w...

  20. The effects of necrotic lesion size and orientation of the femoral component on stress alterations in the proximal femur in hip resurfacing - a finite element simulation

    OpenAIRE

    Tai, Ching-Lung; Chen, Yung-Chou; Hsieh, Pang-Hsin

    2014-01-01

    Background Due to the advantages of its bone-conserving nature, hip resurface arthroplasty (HRA) has recently gained the interest of orthopedic surgeons for the treatment of young and active patients who have osteonerosis of the femoral head. However, in long-term follow-up studies after HRA, narrowing of the femoral neck has often been found, which may lead to fracture. This phenomenon has been attributed to the stress alteration (stress shielding). Studies addressing the effects of necrotic...

  1. Nighttime feeding likely alters morning metabolism but not exercise performance in female athletes.

    Science.gov (United States)

    Ormsbee, Michael J; Gorman, Katherine A; Miller, Elizabeth A; Baur, Daniel A; Eckel, Lisa A; Contreras, Robert J; Panton, Lynn B; Spicer, Maria T

    2016-07-01

    The timing of morning endurance competition may limit proper pre-race fueling and resulting performance. A nighttime, pre-sleep nutritional strategy could be an alternative method to target the metabolic and hydrating needs of the early morning athlete without compromising sleep or gastrointestinal comfort during exercise. Therefore, the purpose of this investigation was to examine the acute effects of pre-sleep chocolate milk (CM) ingestion on next-morning running performance, metabolism, and hydration status. Twelve competitive female runners and triathletes (age, 30 ± 7 years; peak oxygen consumption, 53 ± 4 mL·kg(-1)·min(-1)) randomly ingested either pre-sleep CM or non-nutritive placebo (PL) ∼30 min before sleep and 7-9 h before a morning exercise trial. Resting metabolic rate (RMR) was assessed prior to exercise. The exercise trial included a warm-up, three 5-min incremental workloads at 55%, 65%, and 75% peak oxygen consumption, and a 10-km treadmill time trial (TT). Physiological responses were assessed prior, during (incremental and TT), and postexercise. Paired t tests and magnitude-based inferences were used to determine treatment differences. TT performances were not different ("most likely trivial" improvement with CM) between conditions (PL: 52.8 ± 8.4 min vs CM: 52.8 ± 8.0 min). RMR was "likely" increased (4.8%) and total carbohydrate oxidation (g·min(-1)) during exercise was "possibly" or likely increased (18.8%, 10.1%, 9.1% for stage 1-3, respectively) with CM versus PL. There were no consistent changes to hydration indices. In conclusion, pre-sleep CM may alter next-morning resting and exercise metabolism to favor carbohydrate oxidation, but effects did not translate to 10-km running performance improvements. PMID:27329516

  2. Experimental study and stress analysis of rock bolt anchorage performance

    Directory of Open Access Journals (Sweden)

    Yu Chen

    2014-10-01

    Full Text Available A new method was developed to apply pull-and-shear loads to the bolt specimen in order to evaluate the anchorage performance of the rebar bolt and the D-Bolt. In the tests, five displacing angles (0°, 20°, 40°, 60°, and 90°, two joint gaps (0 mm and 30 mm, and three kinds of host rock materials (weak concrete, strong concrete, and concrete-granite were considered, and stress–strain measurements were conducted. Results show that the ultimate loads of both the D-Bolt and the rebar bolt remained constant with any displacing angles. The ultimate displacement of the D-Bolt changed from 140 mm at the 0° displacing angle (pure pull to approximately 70 mm at a displacing angle greater than 40°. The displacement capacity of the D-Bolt is approximately 3.5 times that of the rebar bolt under pure pull and 50% higher than that of the rebar bolt under pure shear. The compressive stress exists at 50 mm from the bolt head, and the maximum bending moment value rises with the increasing displacing angle. The rebar bolt mobilises greater applied load than the D-Bolt when subjected to the maximum bending. The yielding length (at 0° of the D-Bolt is longer than that of the rebar bolt. The displacement capacity of the bolts increased with the joint gap. The bolt subjected to joint gap effect yields more quickly with greater bending moment and smaller applied load. The displacement capacities of the D-Bolt and the rebar bolt are greater in the weak host rock than that in the hard host rock. In pure shear condition, the ultimate load of the bolts slightly decreases in the hard rock. The yielding speed in the hard rock is higher than that in the weak rock.

  3. Experimental study and stress analysis of rock bolt anchorage performance

    Institute of Scientific and Technical Information of China (English)

    Yu Chen

    2014-01-01

    A new method was developed to apply pull-and-shear loads to the bolt specimen in order to evaluate the anchorage performance of the rebar bolt and the D-Bolt. In the tests, five displacing angles (0?, 20?, 40?, 60?, and 90?), two joint gaps (0 mm and 30 mm), and three kinds of host rock materials (weak concrete, strong concrete, and concrete-granite) were considered, and stressestrain measurements were con-ducted. Results show that the ultimate loads of both the D-Bolt and the rebar bolt remained constant with any displacing angles. The ultimate displacement of the D-Bolt changed from 140 mm at the 0? displacing angle (pure pull) to approximately 70 mm at a displacing angle greater than 40?. The displacement capacity of the D-Bolt is approximately 3.5 times that of the rebar bolt under pure pull and 50%higher than that of the rebar bolt under pure shear. The compressive stress exists at 50 mm from the bolt head, and the maximum bending moment value rises with the increasing displacing angle. The rebar bolt mobilises greater applied load than the D-Bolt when subjected to the maximum bending. The yielding length (at 0?) of the D-Bolt is longer than that of the rebar bolt. The displacement capacity of the bolts increased with the joint gap. The bolt subjected to joint gap effect yields more quickly with greater bending moment and smaller applied load. The displacement capacities of the D-Bolt and the rebar bolt are greater in the weak host rock than that in the hard host rock. In pure shear condition, the ultimate load of the bolts slightly decreases in the hard rock. The yielding speed in the hard rock is higher than that in the weak rock.

  4. STRESS MANAGEMENT: AN APPROACH TO ENSURING HIGH ACADEMIC PERFORMANCE OF BUSINESS EDUCATION STUDENTS

    OpenAIRE

    P.O, IMEOKPARIA; EDIAGBONYA, IMEOKPARIA; KENNEDY, IMEOKPARIA

    2013-01-01

    This paper is specifically prepared to examine the concept of stress management as an approach to ensuring high academic performance of Business Education students. A conceptual framework was developed be the authors in illustrating the inter-relationship that exist among the associated variables on stress. A brief history of the concept of stress was examined and the concept of stress was defined as the biological responses to events that threaten to overwhelm the individual capacity to cope...

  5. A case study to determine stress sources affecting the academic performance

    OpenAIRE

    Aytaç Aydın; Kemal Üçüncü; Taner Taşdemir

    2011-01-01

    Job stress affects academicians in terms of performance, scientific production, job satisfaction and health. This effect may differ according to the academicians in the structure of the organization. It is possible to mention about positive stress if organization structure positively affects academician, but it is called negative stress if it negatively affects. Lack of fee and powers, injustice employee evaluation, not getting in return for work are important stress sources. In this study, ...

  6. Bio-molecular alterations induced by a chemical or radiating stress in isolated human cells

    International Nuclear Information System (INIS)

    After having recalled some aspects of radiobiology (effects of ionizing radiations, molecular targets of radiations, cellular responses with respect to the radiation), the author discusses various aspects of radio-sensitivity: intrinsic radio-sensitivity of tumoral and normal cells, DNA injuries and in vitro radio-sensitivity, genes of susceptibility to ionizing radiations, clustered injuries. Then she reports investigations performed by infrared micro-spectroscopy: characterization of pathological lines, of biological processes, of oxidative injuries induced by xenobiotics, of injuries induced by ionizing radiations

  7. Nonesterified Fatty Acid-Induced Endoplasmic Reticulum Stress in Cattle Cumulus Oocyte Complexes Alters Cell Metabolism and Developmental Competence.

    Science.gov (United States)

    Sutton-McDowall, Melanie L; Wu, Linda L Y; Purdey, Malcolm; Abell, Andrew D; Goldys, Ewa M; MacMillan, Keith L; Thompson, Jeremy G; Robker, Rebecca L

    2016-01-01

    Reduced oocyte quality has been associated with poor fertility of high-performance dairy cows during peak lactation, due to negative energy balance. We examined the role of nonesterified fatty acids (NEFAs), known to accumulate within follicular fluid during under- and overnutrition scenarios, in causing endoplasmic reticulum (ER) stress of in vitro maturated cattle cumulus-oocyte complexes (COCs). NEFA concentrations were: palmitic acid (150 μM), oleic acid (200 μM), and steric acid (75 μM). Abattoir-derived COCs were randomly matured for 24 h in the presence of NEFAs and/or an ER stress inhibitor, salubrinal. Total and hatched blastocyst yields were negatively impacted by NEFA treatment compared with controls, but this was reversed by salubrinal. ER stress markers, activating transcription factor 4 (Atf4) and heat shock protein 5 (Hspa5), but not Atf6, were significantly up-regulated by NEFA treatment within whole COCs but reversed by coincubation with salubrinal. Likewise, glucose uptake and lactate production, measured in spent medium samples, showed a similar pattern, suggesting that cumulus cell metabolism is sensitive to NEFAs via an ER stress-mediated process. In contrast, while mitochondrial DNA copy number was recovered in NEFA-treated oocytes, oocyte autofluorescence of the respiratory chain cofactor, FAD, was lower following NEFA treatment of COCs, and this was not reversed by salubrinal, suggesting the negative impact was via reduced mitochondrial function. These results reveal the significance of NEFA-induced ER stress on bovine COC developmental competence, revealing a potential therapeutic target for improving oocyte quality during peak lactation. PMID:26658709

  8. Ambient particulate air pollution induces oxidative stress and alterations of mitochondria and gene expression in brown and white adipose tissues

    Directory of Open Access Journals (Sweden)

    Harkema Jack R

    2011-07-01

    Full Text Available Abstract Background Prior studies have demonstrated a link between air pollution and metabolic diseases such as type II diabetes. Changes in adipose tissue and its mitochondrial content/function are closely associated with the development of insulin resistance and attendant metabolic complications. We investigated changes in adipose tissue structure and function in brown and white adipose depots in response to chronic ambient air pollutant exposure in a rodent model. Methods Male ApoE knockout (ApoE-/- mice inhaled concentrated fine ambient PM (PM 2.5 or filtered air (FA for 6 hours/day, 5 days/week, for 2 months. We examined superoxide production by dihydroethidium staining; inflammatory responses by immunohistochemistry; and changes in white and brown adipocyte-specific gene profiles by real-time PCR and mitochondria by transmission electron microscopy in response to PM2.5 exposure in different adipose depots of ApoE-/- mice to understand responses to chronic inhalational stimuli. Results Exposure to PM2.5 induced an increase in the production of reactive oxygen species (ROS in brown adipose depots. Additionally, exposure to PM2.5 decreased expression of uncoupling protein 1 in brown adipose tissue as measured by immunohistochemistry and Western blot. Mitochondrial number was significantly reduced in white (WAT and brown adipose tissues (BAT, while mitochondrial size was also reduced in BAT. In BAT, PM2.5 exposure down-regulated brown adipocyte-specific genes, while white adipocyte-specific genes were differentially up-regulated. Conclusions PM2.5 exposure triggers oxidative stress in BAT, and results in key alterations in mitochondrial gene expression and mitochondrial alterations that are pronounced in BAT. We postulate that exposure to PM2.5 may induce imbalance between white and brown adipose tissue functionality and thereby predispose to metabolic dysfunction.

  9. Alternative oxidase: a respiratory electron transport chain pathway essential for maintaining photosynthetic performance during drought stress.

    Science.gov (United States)

    Vanlerberghe, Greg C; Martyn, Greg D; Dahal, Keshav

    2016-07-01

    Photosynthesis and respiration are the hubs of energy metabolism in plants. Drought strongly perturbs photosynthesis as a result of both diffusive limitations resulting from stomatal closure, and in some cases biochemical limitations that are associated with a reduced abundance of key photosynthetic components. The effects of drought on respiration, particularly respiration in the light (RL ), are less understood. The plant mitochondrial electron transport chain includes a non-energy conserving terminal oxidase called alternative oxidase (AOX). Several studies have shown that drought increases AOX transcript, protein and maximum capacity. Here we review recent studies comparing wild-type (WT) tobacco to transgenic lines with altered AOX protein amount. Specifically during drought, RL was compromised in AOX knockdown plants and enhanced in AOX overexpression plants, compared with WT. Significantly, these differences in RL were accompanied by dramatic differences in photosynthetic performance. Knockdown of AOX increased the susceptibility of photosynthesis to drought-induced biochemical limitations, while overexpression of AOX delayed the development of such biochemical limitations, compared with WT. Overall, the results indicate that AOX is essential to maintaining RL during drought, and that this non-energy conserving respiration maintains photosynthesis during drought by promoting energy balance in the chloroplast. This review also outlines several areas for future research, including the possibility that enhancement of non-energy conserving respiratory electron sinks may be a useful biotechnological approach to increase plant performance during stress. PMID:27080742

  10. Working memory performance after acute exposure to the cold pressor stress in healthy volunteers

    OpenAIRE

    Duncko, Roman; Johnson, Linda; Merikangas, Kathleen; Grillon, Christian

    2009-01-01

    Effects of acute stress exposure on learning and memory have been frequently studied in both animals and humans. However, only a few studies have focused specifically on working memory performance and the available data are equivocal. The present study examined working memory performance during the Sternberg item recognition task after exposure to a predominantly adrenergic stressor. Twenty four healthy subjects were randomly assigned to a stress group or a control group. The stress group was...

  11. Nitric Oxide Alleviates Salt Stress Inhibited Photosynthetic Performance by Interacting with Sulfur Assimilation in Mustard

    OpenAIRE

    Fatma, Mehar; Masood, Asim; Per, Tasir S.; Khan, Nafees A

    2016-01-01

    The role of nitric oxide (NO) and sulfur (S) on stomatal responses and photosynthetic performance was studied in mustard (Brassica juncea L.) in presence or absence of salt stress. The combined application of 100 μM NO (as sodium nitroprusside) and 200 mg S kg−1 soil (S) more prominently influenced stomatal behavior, photosynthetic and growth performance both in the absence and presence of salt stress. The chloroplasts from salt-stressed plants had disorganized chloroplast thylakoids, but com...

  12. Clonal Integration Enhances the Performance of a Clonal Plant Species under Soil Alkalinity Stress

    OpenAIRE

    Zhang, Wenjun; Yang, Gaowen; Sun, Juanjuan; Chen, Jishan; Zhang, Yingjun

    2015-01-01

    Clonal plants have been shown to successfully survive in stressful environments, including salinity stress, drought and depleted nutrients through clonal integration between original and subsequent ramets. However, relatively little is known about whether clonal integration can enhance the performance of clonal plants under alkalinity stress. We investigated the effect of clonal integration on the performance of a typical rhizomatous clonal plant, Leymus chinensis, using a factorial experimen...

  13. Performance and recovery: stress profiles in professional ballroom dancers.

    Science.gov (United States)

    Liiv, Helena; Jurimae, Toivo; Klonova, Alina; Cicchella, Antonio

    2013-06-01

    Like other athletes, ballroom dancers often compete in short time in different countries under condition of high stress, subjecting them to risk of injury and burnout. In the present study, we measured the aerobic and anaerobic capacities (both during dance and during a simulated ballroom competition), agility, hand and abdominal strength, jumping capacity, flexibility, and balance in 16 top-level couples of ballroom dancers (8 males, 8 females). The in-season level of perceived stress and recovery was assessed using the Rest Q 76 questionnaire, and the relationship with aerobic and anaerobic capacity and with the other tests was studied. Our results show a very high level of aerobic/anaerobic fitness in this population, as well as a high level of stress in males. Balance and experience (age of the subjects) appear to be key characteristics linked to the position in the IDSF World Ranking (world ranking points = 8.67 x age + 5.86 x balance + 1174.65; R2 = 0.740). Emotional stress (r = 0.83, p = 0.04), social stress (r = 0.72, p = 0.032), and sleep quality (r = 0.92, p = 0.001) scales of the Rest Q appear also to be linked with balance but only in females. PMID:23752279

  14. Anti-inflammatory Montelukast prevents toxic effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin: Oxidative stress, histological alterations in liver, and serum cytokine levels.

    Science.gov (United States)

    Bentli, Recep; Ciftci, Osman; Cetin, Asli; Otlu, Ali

    2016-05-01

    This study aimed to investigate the potential beneficial effects of the montelukast (ML) on oxidative stress and histological alterations in liver tissues and cytokine levels in rats intoxicated with 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Rats were divided randomly into four equal groups (control, TCDD, ML, TCDD + ML). TCDD were administered by gavages dissolved in corn oil at the doses of 2 µg/kg/week, and ML was given intraperitoneally at the dose of 10 mg/kg/day. Oxidative status, histological alterations, and cytokine levels were analyzed on day 60. The results showed that although TCDD induced oxidative stress via significant increase in formation of thiobarbituric acid reactive substance, it caused a significant decline in glutathione (GSH), catalase (CAT), and superoxide dismutase (SOD) levels in liver. Besides, TCDD led to significant histopathological damage in liver and serum cytokine levels alterations (increase in tumor necrosis factor α and interleukin 1β levels). In contrast, ML treatment reversed oxidative effects of TCDD by increasing the levels of GSH, CAT, and SOD and decreasing the formation of TBARS. Also, it can normalize the levels of histological and cytokine alterations induced by TCDD. In conclusion, it was determined that TCDD exposure caused adverse effects on cytokine levels, histological alterations, and oxidative stress in rats. However, ML treatment partially eliminated toxic effects of TCDD. Thus, it was judged that coadministration of ML with TCDD may be useful to attenuate the negative effects of TCDD. PMID:24215062

  15. D-Methionine attenuated cisplatin-induced vestibulotoxicity through altering ATPase activities and oxidative stress in guinea pigs

    International Nuclear Information System (INIS)

    Cisplatin has been used as a chemotherapeutic agent to treat many kinds of malignancies. Its damage to the vestibulo-ocular reflex (VOR) system has been reported. However, the underlying biochemical change in the inner ear or central vestibular nervous system is not fully understood. In this study, we attempted to examine whether cisplatin-induced vestibulotoxicity and D-methionine protection were correlated with the changes of ATPase activities and oxidative stress of ampullary tissue of vestibules as well as cerebellar cortex (the inhibitory center of VOR system) of guinea pigs. By means of a caloric test coupled with electronystagmographic recordings, we found that cisplatin exposure caused a dose-dependent (1, 3, or 5 mg/kg) vestibular dysfunction as revealed by a decrease of slow phase velocity (SPV). In addition, cisplatin significantly inhibited the Na+, K+-ATPase and Ca2+-ATPase activities in the ampullary tissue with a good dose-response relationship but not those of cerebellar cortex. Regression analysis indicated that a decrease of SPV was well correlated with the reduction of Na+, K+-ATPase and Ca2+-ATPase activities of the ampullary tissue. D-Methionine (300 mg/kg) reduced both abnormalities of SPV and ATPase activities in a correlated manner. Moreover, cisplatin exposure led to a significant dose-dependent increase of lipid peroxidation and nitric oxide concentrations of the vestibules, which could be significantly suppressed by D-methionine. However, cisplatin did not alter the levels of lipid peroxidation and nitric oxide of the cerebellum. In conclusion, cisplatin inhibited ATPase activities and increased oxidative stress in guinea pig vestibular labyrinths. D-Methionine attenuated cisplatin-induced vestibulotoxicity associated with ionic disturbance through its antioxidative property

  16. Molecular hydrogen protects chondrocytes from oxidative stress and indirectly alters gene expressions through reducing peroxynitrite derived from nitric oxide

    Directory of Open Access Journals (Sweden)

    Hanaoka Teruyasu

    2011-08-01

    Full Text Available Abstract Background Molecular hydrogen (H2 functions as an extensive protector against oxidative stress, inflammation and allergic reaction in various biological models and clinical tests; however, its essential mechanisms remain unknown. H2 directly reacts with the strong reactive nitrogen species peroxynitrite (ONOO- as well as hydroxyl radicals (•OH, but not with nitric oxide radical (NO•. We hypothesized that one of the H2 functions is caused by reducing cellular ONOO-, which is generated by the rapid reaction of NO• with superoxides (•O2-. To verify this hypothesis, we examined whether H2 could restore cytotoxicity and transcriptional alterations induced by ONOO- derived from NO• in chondrocytes. Methods We treated cultured chondrocytes from porcine hindlimb cartilage or from rat meniscus fibrecartilage with a donor of NO•, S-nitroso-N-acetylpenicillamine (SNAP in the presence or absence of H2. Chondrocyte viability was determined using a LIVE/DEAD Viability/Cytotoxicity Kit. Gene expressions of the matrix proteins of cartilage and the matrix metalloproteinases were analyzed by reverse transcriptase-coupled real-time PCR method. Results SNAP treatment increased the levels of nitrated proteins. H2 decreased the levels of the nitrated proteins, and suppressed chondrocyte death. It is known that the matrix proteins of cartilage (including aggrecan and type II collagen and matrix metalloproteinases (such as MMP3 and MMP13 are down- and up-regulated by ONOO-, respectively. H2 restoratively increased the gene expressions of aggrecan and type II collagen in the presence of H2. Conversely, the gene expressions of MMP3 and MMP13 were restoratively down-regulated with H2. Thus, H2 acted to restore transcriptional alterations induced by ONOO-. Conclusions These results imply that one of the functions of H2 exhibits cytoprotective effects and transcriptional alterations through reducing ONOO-. Moreover, novel pharmacological strategies

  17. Challenge and Hindrance Stress: Relationships with Exhaustion, Motivation to Learn, and Learning Performance

    Science.gov (United States)

    LePine, Jeffrey A.; LePine, Marcie A.; Jackson, Christine L.

    2004-01-01

    In a study of 696 learners, the authors found that stress associated with challenges in the learning environment had a positive relationship with learning performance and that stress associated with hindrances in the learning environment had a negative relationship with learning performance. They also found evidence suggesting that these…

  18. The Effect of Stress and Recovery on Field-test Performance in Floorball

    NARCIS (Netherlands)

    van der Does, H. T. D.; Brink, M. S.; Visscher, C.; Huijgen, B. C. H.; Frencken, W. G. P.; Lemmink, K. A. P. M.

    2015-01-01

    Physical and psychosocial stress and recovery are important performance determinants. A holistic approach that monitors these performance determinants over a longer period of time is lacking. Therefore this study aims to investigate the effect of a player's physical and psychosocial stress and recov

  19. Relation of Organizational Structure to Job Satisfaction, Anxiety-Stress, and Performance

    Science.gov (United States)

    Ivancevich, John M.; Donnelly, James H., Jr.

    1975-01-01

    Reports on the relationship between organizational shape or structure (tall, medium, and flat) and job satisfaction, anxiety-stress, and performance. Indicates that salesmen in flat organizations perceive more autonomy and more satisfaction with respect to self-actualization, perceive lower amounts of anxiety-stress, and perform more efficiently.…

  20. Relationships between Academic Stress, Social Support, Mental Health and Academic Performance in Venezuelan University Students

    Directory of Open Access Journals (Sweden)

    LYA FELDMAN

    2008-12-01

    Full Text Available The objective of the present study was to evaluate academic stress, social support and their relationships with mental health and academic performance in university students. Three hundred and twenty one students from a technological university in Caracas, Venezuela, responded instruments on academic stress, social support and mental health during the most academically stressful period. The results indicate that favorable conditions of mental health were associated to more social support and less academic stress. In women, higher stress levels were associated to a lesser amount of social support from friends whereas in men stress was related to less social support coming from close people and general social support. Both displayed better performance when perceived higher levels of academic stress and the social support of the near people was moderate. Results are discussed in terms of their implications for academic life and mental health in university students.

  1. Oral administration of curcumin relieves behavioral alterations and oxidative stress in the frontal cortex, hippocampus, and striatum of ovariectomized Wistar rats.

    Science.gov (United States)

    Da Silva Morrone, Maurilio; Schnorr, Carlos Eduardo; Behr, Guilherme Antônio; Gasparotto, Juciano; Bortolin, Rafael Calixto; Moresco, Karla Suzana; Bittencourt, Leonardo; Zanotto-Filho, Alfeu; Gelain, Daniel Pens; Moreira, José Cláudio Fonseca

    2016-06-01

    Menopause occurs gradually and is characterized by increased susceptibility to developing mood disorders. Several studies have suggested treatments based on the antioxidant properties of vitamins and herbal compounds as an alternative to hormone replacement therapies, with few or none reporting toxicity. The present study was performed to explore the effects of curcumin oral supplementation on anxiety-like behavior and oxidative stress parameters in different central nervous system (CNS) areas of ovariectomized (OVX) rats. Female Wistar rats were randomly divided into either sham-operated or OVX groups. Sham-operated group (n=8) and an OVX group (n=11) were treated with vehicle, and the other two OVX groups received curcumin at 50 or 100mg/kg/day doses (n=8/group). Elevated plus maze (EPM) test was performed on the 28th day of treatment. On the 30th day, animals were killed and the dissected brain regions were removed and stored at-80°C until analysis. Ovariectomy induced deficit in the locomotor activity and increased anxiety-like behavior. Moreover, OVX rats showed increased lipid oxidized in the frontal cortex and striatum, increased hippocampal and striatal carbonylated protein level, and decreased striatal thiol content of non-protein fraction indicative of a glutathione (GSH) pool. Curcumin oral treatment for 30days reduced oxidative stress in the CNS areas as well as the behavior alterations resulting from ovariectomy. Curcumin supplementation attenuated most of these parameters to sham comparable values, suggesting that curcumin could have positive effects against anxiety-like disturbances and brain oxidative damage due to hormone deprivation. PMID:27142750

  2. Potential role of oxidative stress in mediating the effect of altered gravity on the developing rat cerebellum

    Science.gov (United States)

    Sajdel-Sulkowska, Elizabeth M.; Nguon, Kosal; Sulkowski, Zachary L.; Lipinski, Boguslaw

    We have previously reported that perinatal exposure to hypergravity affects cerebellar structure and motor coordination in rat neonates. In the present study, we explored the hypothesis that exposure to hypergravity results in oxidative stress that may contribute to the decrease in Purkinje cell number and the impairment of motor coordination in hypergravity-exposed rat neonates. To test this hypothesis we compared cerebellar oxidative stress markers 3-nitrotyrosine (3-NT; an index of oxidative protein modification) and 8-hydroxy-2'-deoxyguanosine (8-OH-dG; an index of oxidative DNA damage) between stationary control (SC) and rat neonates exposed to 1.65 G (HG) on a 24-ft centrifuge from gestational day (G) 8 to postnatal day (P) 21. The levels of 3-NT and 8-OH-dG were determined by specific ELISAs. We also compared the Purkinje cell number (stereorologically) and rotarod performance between the two groups. The levels of 3-NT were increased only in HG females on P6 and on P12 in the cerebellum, and only in HG females on P12 in the extracellabellar tissue. Limited cerebellar data suggests an increase in the levels of 8-OH-dG on P12 only in HG females. In extracerebellar tissue the increase in 8-OH-dG levels was observed in both HG males and HG females except on P6 when it was only observed in HG males. While preliminary, these data suggest that the effect of hypergravity on the developing brain is sex-dependent and may involve oxidative stress. Oxidative stress may, in turn, contribute to the decrease Purkinje cell number and impaired motor behavior observed in hypergravity-exposed rats.

  3. Altered myocardial perfusion during dobutamine stress testing in silent versus symptomatic myocardial ischaemia assessed by quantitative MIBI SPET imaging

    Energy Technology Data Exchange (ETDEWEB)

    Elhendy, A. [Thoraxcenter, Univ. Hospital, Rotterdam-Dijkzigt (Netherlands); Geleijnse, M.L. [Thoraxcenter, Univ. Hospital, Rotterdam-Dijkzigt (Netherlands); Roelandt, J.R.T.C. [Thoraxcenter, Univ. Hospital, Rotterdam-Dijkzigt (Netherlands); Cornel, J.H. [Thoraxcenter, Univ. Hospital, Rotterdam-Dijkzigt (Netherlands); Domburg, R.T van [Thoraxcenter, Univ. Hospital, Rotterdam-Dijkzigt (Netherlands); Reijs, A.E.M. [Dept. of Nuclear Medicine, Univ. Hospital, Rotterdam-Dijkzigt (Netherlands); Nierop, P.R. [Thoraxcenter, Univ. Hospital, Rotterdam-Dijkzigt (Netherlands); Fioretti, P.M. [Dept. of Nuclear Medicine, Univ. Hospital, Rotterdam-Dijkzigt (Netherlands)

    1996-10-01

    The aim of the study was to compare the extent and severity of reversible underperfusion in silent versus painful myocardial ischaemia during the dobutamine stress test. A consecutive series of 85 patients with significant coronary artery disease and reversible perfusion defects on technetium-99m methoxyisobutylisonitrile single-photon emission tomography performed at rest and during high-dose dobutamine stress (up to 40 {mu}g kg{sup -1} min{sup -1}) were studied. The left ventricle was divided into six segments. An ischaemic perfusion score was derived quantitatively by subtracting the rest from the stress defect score. Patients with multivessel disease had a higher ischaemic score (610{+-}762 vs 310{+-}411, P<0.05) and a higher number of reversible perfusion defects (2.1{+-}1.2 vs 1.1{+-}0.8, P<0.01) than patients with single-vessel disease. Typical angina occurred in 37 patients (44%) during the test. There was no significant difference between patients with and patients without angina with respecft to age, gender, peak rate-pressure product, prevalence of previous myocardial infarction, diabetes mellitus, multivessel disease or number of stenotic coronary arteries. Stress, rest and ischaemic scores as well as the number and distribution of reversible defects were not different in patients with and patients without angina. Patients with angina more frequently had a history of typical angina before the test (43% vs 17%, P<0.01) and ST-segment depression during the test (54% vs 25%, P<0.01). It is concluded that in patients with coronary artery disease and ischaemia detected by dobutamine scintigraphy, the extent and severity of coronary artery disease and myocardial perfusion abnormalities are similar with or without angina during stess testing. (orig.)

  4. Exercise copes with prolonged stress-induced impairment of spatial memory performance by endoplasmic reticulum stress

    OpenAIRE

    Kang, Jong-Seok

    2015-01-01

    Purpose The present study demonstrates that prolonged restraint administration for 21 days caused memory impairment and induced hippocampal endoplasmic reticulum (ER) stress-mediated apoptosis. On the contrary, this change was revered by treadmill running for 8 weeks. Repeated psychological stress caused an increase in escape latency time in the water maze test, accompanied by the induction of glucose-regulated protein 78 (GRP78), CCAAT/enhancer-binding protein homologous protein (CHOP), and ...

  5. Altered regional homogeneity in post-traumatic stress disorder: a resting-state functional magnetic resonance imaging study

    Institute of Scientific and Technical Information of China (English)

    Yan Yin; Baoci Shan; Qiyong Gong; Lingjiang Li; Changfeng Jin; Lisa T.Eyler; Hua Jin; Xiaolei Hu; Lian Duan; Huirong Zheng; Bo Feng; Xuanyin Huang

    2012-01-01

    Objective Little is known about the brain systems that contribute to vulnerability to post-traumatic stress disorder (PTSD).Comparison of the resting-state patterns of intrinsic functional synchronization,as measured by functional magnetic resonance imaging (fMRI),between groups with and without PTSD following a traumatic event can help identify the neural mechanisms of the disorder and targets for intervention.Methods Fifty-four PTSD patients and 72 matched traumatized subjects who experienced the 2008 Sichuan earthquake were imaged with blood oxygen level-dependent (BOLD) fMRI and analyzed using the measure of regional homogeneity (ReHo) during the resting state.Results PTSD patients presented enhanced ReHo in the left inferior parietal lobule and right superior frontal gyrus,and reduced ReHo in the right middle temporal gyrus and lingual gyrus,relative to traumatized individuals without PTSD.Conclusion Our findings showed that abnormal brain activity exists under resting conditions in PTSD patients who had been exposed to a major earthquake.Alterations in the local functional connectivity of cortical regions are likely to contribute to the neural mechanisms underlying PTSD.

  6. Quercus infectoria galls possess antioxidant activity and abrogates oxidative stress-induced functional alterations in murine macrophages.

    Science.gov (United States)

    Kaur, Gurpreet; Athar, Mohammad; Alam, M Sarwar

    2008-02-15

    The present study reports the antioxidant activity of ethanolic extract of Quercus infectoria galls. The antioxidant potency of galls was investigated employing several established in vitro model systems. Their protective efficacy on oxidative modulation of murine macrophages was also explored. Gall extract was found to contain a large amount of polyphenols and possess a potent reducing power. HPTLC analysis of the extract suggested it to contain 19.925% tannic acid (TA) and 8.75% gallic acid (GA). The extract potently scavenged free radicals including DPPH (IC(50)~0.5 microg/ml), ABTS (IC(50)~1 microg/ml), hydrogen peroxide (H(2)O(2)) (IC(50)~2.6 microg/ml) and hydroxyl (*OH) radicals (IC(50)~6 microg/ml). Gall extract also chelated metal ions and inhibited Fe(3+) -ascorbate-induced oxidation of protein and peroxidation of lipids. Exposure of rat peritoneal macrophages to tertiary butyl hydroperoxide (tBOOH) induced oxidative stress in them and altered their phagocytic functions. These macrophages showed elevated secretion of lysosomal hydrolases, and attenuated phagocytosis and respiratory burst. Activity of macrophage mannose receptor (MR) also diminished following oxidant exposure. Pretreatment of macrophages with gall extract preserved antioxidant armory near to control values and significantly protected against all the investigated functional mutilations. MTT assay revealed gall extract to enhance percent survival of tBOOH exposed macrophages. These results indicate that Q. infectoria galls possess potent antioxidant activity, when tested both in chemical as well as biological models. PMID:18076871

  7. Levels of Stress and Academic Performance in Baccalaureate Nursing Students.

    Science.gov (United States)

    Gwele, Nonthandazo Sylvia; Uys, Leana Ria

    1998-01-01

    Comparison of 39 nursing students in an old program with 62 in the first year of a new baccalaureate program showed the former experienced more stress and did not perceive the program as challenging. Academic gains of new-program students were not as significant as those of old-program students. (SK)

  8. Complexity of physiological responses decreases in high-stress musical performance.

    Science.gov (United States)

    Williamon, Aaron; Aufegger, Lisa; Wasley, David; Looney, David; Mandic, Danilo P

    2013-12-01

    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. PMID:24068177

  9. Complexity of physiological responses decreases in high-stress musical performance

    Science.gov (United States)

    Williamon, Aaron; Aufegger, Lisa; Wasley, David; Looney, David; Mandic, Danilo P.

    2013-01-01

    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. PMID:24068177

  10. STRESS; THE VULNERABILITY AND ASSOCIATION WITH DRIVING PERFORMANCE

    OpenAIRE

    B. M.T. Shamsul; S. Khairunnisa; Y. G. Ng; M. Y. Irwan Syah

    2014-01-01

    Several factors may contribute to occurrence of road accidents which are human factors, vehicle factor, road factor and environmental factor. There has been recent evidence of a relationship between road accidents and emotional distress as well as fatigue. Monotonous and complex road environments are the road factor that relates to the internal factor within driver. The overall aim of this study was to compare driving stress, fatigue and driving error between complex and monotonous driving. T...

  11. Growth and Eco-Physiological Performance of Cotton Under Water Stress Conditions

    Institute of Scientific and Technical Information of China (English)

    WANG Chun-yan; Isoda Akihiro; LI Mao-song; WANG Dao-long

    2007-01-01

    A cotton cultivar Xinluzao 8 was grown under four levels of water stress treatments (normal irrigation, slight, mild and severe water stress) from the initial reproductive growth stage in Shihezi, Xinjiang, China, in 2002, to evaluate the growth and eco-physiological performances. Under water stress conditions, the transpiration ability decreased while the leaf temperature increased. Although the relative leaf water content decreased as water stress increased, the differences among the treatments were small, indicating that cotton has high ability in maintaining water in leaf. The stomatal density increased as water stress increased, while the maximum stomatal aperture reduced only in the severest stressed plants.The time of the maximum stomatal aperture was delayed in the mild and severe stressed plants. When severe stress occurred, the stomata were kept open until the transpiration decreased to nearly zero, suggesting that the stomata might not be the main factor in adjusting transpiration in cotton. Cotton plant has high adaptation ability to water stress conditions because of decrease in both stomatal conductance and hydraulic conductance from soil-to-leaf pathway. The actual quantum yield of photosystem Ⅱ (PS Ⅱ) decreased under water stress conditions, while the maximum quantum yield of PS Ⅱ did not vary among treatments, suggesting that PS Ⅱ would not be damaged by water stress. The total dry weight reduced as water stress increased.

  12. Improving trainees’ performances while under stress using real-time feedback

    OpenAIRE

    Cohen, I.

    2015-01-01

    Professionals working in different domains often experience stressful conditions evoked by disasters or crisis scenarios. Regardless of these conditions, they have to perform at high standards in order to preserve safety for themselves, avoid any casualties, and to resolve the overall situation. Stress, however, negatively affects cognitive processes and thereby decreases performances. This doctoral thesis aims to improve professionals’ decisions and performances when working in risk- and str...

  13. The impact of cardiac perception on emotion experience and cognitive performance under mental stress.

    Science.gov (United States)

    Kindermann, Nicole K; Werner, Natalie S

    2014-12-01

    Mental stress evokes several physiological responses such as the acceleration of heart rate, increase of electrodermal activity and the release of adrenaline. Moreover, physiological stress responses interact with emotional and behavioral stress responses. In the present study we provide evidence that viscero-sensory feedback from the heart (cardiac perception) is an important factor modulating emotional and cognitive stress responses. In our study, we compared participants with high versus low cardiac perception using a computerized mental stress task, in which they had to respond to rapidly presented visual and acoustic stimuli. Additionally, we assessed physiological responses (heart rate, skin conductance). Participants high in cardiac perception reported more negative emotions and showed worse task performance under the stressor than participants low in cardiac perception. These results were not moderated by physiological responses. We conclude that cardiac perception modulates stress responses by intensifying negative emotions and by impairing cognitive performance. PMID:24719221

  14. Stress and performance: do service orientation and emotional energy moderate the relationship?

    Science.gov (United States)

    Smith, Michael R; Rasmussen, Jennifer L; Mills, Maura J; Wefald, Andrew J; Downey, Ronald G

    2012-01-01

    The current study examines the moderating effect of customer service orientation and emotional energy on the stress-performance relationship for 681 U.S. casual dining restaurant employees. Customer service orientation was hypothesized to moderate the stress-performance relationship for Front-of-House (FOH) workers. Emotional energy was hypothesized to moderate stress-performance for Back-of-House (BOH) workers. Contrary to expectations, customer service orientation failed to moderate the effects of stress on performance for FOH employees, but the results supported that customer service orientation is likely a mediator of the relationship. However, the hypothesis was supported for BOH workers; emotional energy was found to moderate stress performance for these employees. This finding suggests that during times of high stress, meaningful, warm, and empathetic relationships are likely to impact BOH workers' ability to maintain performance. These findings have real-world implications in organizational practice, including highlighting the importance of developing positive and meaningful social interactions among workers and facilitating appropriate person-job fits. Doing so is likely to help in alleviating worker stress and is also likely to encourage worker performance. PMID:22122550

  15. Chronic Stress Induces Structural Alterations in Splenic Lymphoid Tissue That Are Associated with Changes in Corticosterone Levels in Wistar-Kyoto Rats

    Directory of Open Access Journals (Sweden)

    María Eugenia Hernandez

    2013-01-01

    Full Text Available Major depressive disorder patients present chronic stress and decreased immunity. The Wistar-Kyoto rat (WKY is a strain in which the hypothalamic-pituitary-adrenal axis is overactivated. To determine whether chronic stress induces changes in corticosterone levels and splenic lymphoid tissue, 9-week-old male rats were subject to restraint stress (3 h daily, chemical stress (hydrocortisone treatment, 50 mg/Kg weight, mixed stress (restraint plus hydrocortisone, or control treatment (without stress for 1, 4, and 7 weeks. The serum corticosterone levels by RIA and spleens morphology were analyzed. Corticosterone levels as did the structure, size of the follicles and morphology of the parenchyma (increase in red pulp in the spleen, varied depending on time and type of stressor. These changes indicate that chronic stress alters the immune response in the spleen in WKY rats by inducing morphological changes, explaining in part the impaired immunity that develops in organisms that are exposed to chronic stress.

  16. Estrogen-induced breast cancer: Alterations in breast morphology and oxidative stress as a function of estrogen exposure

    International Nuclear Information System (INIS)

    Epidemiological evidence indicates that prolonged lifetime exposure to estrogen is associated with elevated breast cancer risk in women. Oxidative stress and estrogen receptor-associated proliferative changes are suggested to play important roles in estrogen-induced breast carcinogenesis. In the present study, we investigated changes in breast morphology and oxidative stress following estrogen exposure. Female ACI rats were treated with 17β-estradiol (E2, 3 mg, s.c.) for either 7, 15, 120 or 240 days. Animals were euthanized, tissues were excised, and portions of the tissues were either fixed in 10% buffered formalin or snap-frozen in liquid nitrogen. Paraffin-embedded tissues were examined for histopathologic changes. Proliferative changes appeared in the breast after 7 days of E2 exposure. Atypical ductal proliferation and significant reduction in stromal fat were observed following 120 days of E2 exposure. Both in situ and invasive carcinomas were observed in the majority of the mammary glands from rats treated with E2 for 240 days. Palpable breast tumors were observed in 82% of E2-treated rats after 228 days, with the first palpable tumor appearing after 128 days. No morphological changes were observed in the livers, kidneys, lungs or brains of rats treated with E2 for 240 days compared to controls. Furthermore, 8-isoprostane (8-isoPGF2α) levels as well as the activities of antioxidant enzymes, such as glutathione peroxidase, superoxide dismutase and catalase, were quantified in the breast tissues of rats treated with E2 for 7, 15, 120 and 240 days and compared to activity levels in age-matched controls. 8-isoPGF2α levels displayed time-dependent increases upon E2 treatment and were significantly higher than control levels at the 15, 120 and 240 day time-points. 8-isoPGF2α observed in E2-induced mammary tumors were significantly higher than levels found in control mammary tissue from age-matched animals. Similarly, alterations in glutathione peroxidase and

  17. Relationships between Academic Stress, Social Support, Mental Health and Academic Performance in Venezuelan University Students

    OpenAIRE

    LYA FELDMAN; LILA GONCALVES; GRACE CHACÓN-PUIGNAU; JOANMIR ZARAGOZA; NURI BAGÉS; JOAN DE PABLO

    2008-01-01

    The objective of the present study was to evaluate academic stress, social support and their relationships with mental health and academic performance in university students. Three hundred and twenty one students from a technological university in Caracas, Venezuela, responded instruments on academic stress, social support and mental health during the most academically stressful period. The results indicate that favorable conditions of mental health were associated to more social support and ...

  18. Impact of flexible scheduling on employee performance regarding stress and work-family conflict

    OpenAIRE

    Raja Abdul Ghafoor Khan; Furqan Ahmad Khan; Dr. Muhammad Aslam Khan; Mohsin Shakeel

    2011-01-01

    Stress, work-family conflicts and flexible scheduling are three of the most important elements in organizational studies. The focus of current study is to understand the effect of Stress,work family conflicts and flexible scheduling on employee’s performance and also to understand whether flexible scheduling helps in reducing stress and work-family conflicts or not. The back bone of this study is the secondary data comprised of comprehensive literature review. A survey has also been conducted...

  19. Cardioprotective effects of lipoic acid, quercetin and resveratrol on oxidative stress related to thyroid hormone alterations in long-term obesity.

    Science.gov (United States)

    Cheserek, Maureen Jepkorir; Wu, Guirong; Li, Longnan; Li, Lirong; Karangwa, Eric; Shi, Yonghui; Le, Guowei

    2016-07-01

    This study investigated possible mechanisms for cardioprotective effects of lipoic acid (LA), quercetin (Q) and resveratrol (R) on oxidative stress related to thyroid hormone alterations in long-term obesity. Female C57BL/6 mice were fed on high-fat diet (HFD), HFD+LA, HFD+R, HFD+Q and normal diet for 26weeks. Body weight, blood pressure, thyroid hormones, oxidative stress markers, angiotensin converting enzyme (ACE), nitric oxide synthase (NOS) and ion pump activities were measured, and expression of cardiac genes was analyzed by real-time polymerase chain reaction. HFD induced marked increase (Pblood pressure and oxidative stress, while plasma triidothyronine levels reduced. ACE activity increased (Pblood pressure. In conclusion, LA, resveratrol and quercetin supplementation reduces obesity thereby restoring plasma thyroid hormone levels and attenuating oxidative stress in the heart and thus may have therapeutic potential in heart diseases. PMID:27260466

  20. Desmodium gangeticum (Linn.) DC. exhibits antihypertrophic effect in isoproterenol-induced cardiomyoblasts via amelioration of oxidative stress and mitochondrial alterations.

    Science.gov (United States)

    Sankar, Vandana; Pangayarselvi, Balasubramaniam; Prathapan, Ayyappan; Raghu, Kozhiparambil Gopalan

    2013-01-01

    Cardiac hypertrophy occurs in response to increased workload, such as hypertension or valvular heart disease. Oxidative stress has been implicated in cardiac hypertrophy and in its transition to heart failure. This study was taken up with the objective to evaluate the role of oxidative stress in cardiomyoblast hypertrophy and its modulation by Desmodium gangeticum (DG) that has been traditionally used in Ayurveda, an Indian system of medicine. The methanolic root extract was analyzed for total phenolic content and tested for antioxidant potential. Hypertrophy was induced by exposing H9c2 cell line to β-adrenergic receptor agonist, isoproterenol (ISO), for 96 hours. Analyses of reactive oxygen species (ROS) generation, mitochondrial transmembrane potential ([INCREMENT]Ψm), and integrity of permeability transition were performed in ISO as well as Desmodium and ISO-cotreated cells. The results demonstrated potent free radical scavenging activity of DG. Cell line studies showed significant increase in ROS generation, dissipation of [INCREMENT]Ψm, and permeability transition pore opening in ISO-treated cells. Desmodium was found to attenuate ISO-induced hypertrophy by reduction of ROS generation, restoration of [INCREMENT]Ψm, and prevention of permeability transition pore opening. This study is the first documentation of the modulatory effect of DG on cardiac hypertrophy. PMID:23052030

  1. Relationship between Occupational Stress, Emotional Intelligence and Job Performance: An Empirical Study in Malaysia

    Directory of Open Access Journals (Sweden)

    Azman Ismail

    2009-10-01

    Full Text Available This study was conducted to examine the effect of emotional intelligence in the relationship between occupational stress and job performance using 104 usable questionnaires gathered from academic employees who work in private institutions of higher learning in Kuching City, Malaysia. The outcomes of testing research hypothesis using a stepwise regression analysis showed that relationship between occupational stress and emotional intelligence significantly correlated with job performance. Statistically, the result confirms that the inclusion of emotional intelligence in the analysis has mediated the effect of occupational stress on job performance in the organizational sector sample. Further, implications and discussion are elaborated.

  2. Effect of thermal stress on the performance of HgCdTe/Si diodes and FPAs

    International Nuclear Information System (INIS)

    As a typical hetero-epitaxial material, the HgCdTe film which directly grows on the Si substrate possesses great residual stress for the large lattice and thermal expansion mismatch. Thermal stress caused by the thermal expansion mismatch dominates the stress mechanism after growth and seriously affects the device performance. In this paper, the performance of the HgCdTe/Si material, diodes and focal plane arrays under different thermal stress condition was studied. The experimental results indicate that the performance regularly changes with the thermal stress and all the results can be duplicated and recoverable. By analyzing the changes of the energy band under different stress conditions, it was found that the stress in the HgCdTe film impacts the film's characteristics. The HgCdTe film with tensile stress exhibits higher electron mobility, while with the compressive stress, the film exhibits higher hole mobility than that of the bulk HgCdTe crystal. Finally, the theoretical analysis can explain the experimental results well. (paper)

  3. Behavioral and molecular neuroepigenetic alterations in prenatally stressed mice: relevance for the study of chromatin remodeling properties of antipsychotic drugs.

    Science.gov (United States)

    Dong, E; Tueting, P; Matrisciano, F; Grayson, D R; Guidotti, A

    2016-01-01

    We have recently reported that mice born from dams stressed during pregnancy (PRS mice), in adulthood, have behavioral deficits reminiscent of behaviors observed in schizophrenia (SZ) and bipolar (BP) disorder patients. Furthermore, we have shown that the frontal cortex (FC) and hippocampus of adult PRS mice, like that of postmortem chronic SZ patients, are characterized by increases in DNA-methyltransferase 1 (DNMT1), ten-eleven methylcytosine dioxygenase 1 (TET1) and exhibit an enrichment of 5-methylcytosine (5MC) and 5-hydroxymethylcytosine (5HMC) at neocortical GABAergic and glutamatergic gene promoters. Here, we show that the behavioral deficits and the increased 5MC and 5HMC at glutamic acid decarboxylase 67 (Gad1), reelin (Reln) and brain-derived neurotrophic factor (Bdnf) promoters and the reduced expression of the messenger RNAs (mRNAs) and proteins corresponding to these genes in FC of adult PRS mice is reversed by treatment with clozapine (5 mg kg(-1) twice a day for 5 days) but not by haloperidol (1 mg kg(-1) twice a day for 5 days). Interestingly, clozapine had no effect on either the behavior, promoter methylation or the expression of these mRNAs and proteins when administered to offspring of nonstressed pregnant mice. Clozapine, but not haloperidol, reduced the elevated levels of DNMT1 and TET1, as well as the elevated levels of DNMT1 binding to Gad1, Reln and Bdnf promoters in PRS mice suggesting that clozapine, unlike haloperidol, may limit DNA methylation by interfering with DNA methylation dynamics. We conclude that the PRS mouse model may be useful preclinically in screening for the potential efficacy of antipsychotic drugs acting on altered epigenetic mechanisms. Furthermore, PRS mice may be invaluable for understanding the etiopathogenesis of SZ and BP disorder and for predicting treatment responses at early stages of the illness allowing for early detection and remedial intervention. PMID:26756904

  4. Stress and Performance: Effects of Subjective Work Load and Time Urgency.

    Science.gov (United States)

    Friend, Kenneth E.

    1982-01-01

    Measured subjective work load, time urgency, and other stress/motivation variables for management personnel taking a demanding problem-solving exam. Data suggest increases in psychological stresses like subjectively high work load and time urgency uniformly impair performance across the whole range of these variables. (Author)

  5. Detecting Stress Patterns Is Related to Children's Performance on Reading Tasks

    Science.gov (United States)

    Gutierrez-Palma, Nicolas; Raya-Garcia, Manuel; Palma-Reyes, Alfonso

    2009-01-01

    This paper investigates the relationship between the ability to detect changes in prosody and reading performance in Spanish. Participants were children aged 6-8 years who completed tasks involving reading words, reading pseudowords, stressing pseudowords, and reproducing pseudoword stress patterns. Results showed that the capacity to reproduce…

  6. Perceived Stress, Energy Drink Consumption, and Academic Performance among College Students

    Science.gov (United States)

    Pettit, Michele L.; DeBarr, Kathy A.

    2011-01-01

    Objective: This study explored relationships regarding perceived stress, energy drink consumption, and academic performance among college students. Participants: Participants included 136 undergraduates attending a large southern plains university. Methods: Participants completed surveys including items from the Perceived Stress Scale and items to…

  7. The Relationship between Mental Health, Acculturative Stress, and Academic Performance in a Latino Middle School Sample

    Science.gov (United States)

    Albeg, Loren J.; Castro-Olivo, Sara M.

    2014-01-01

    This study evaluated the relationship between acculturative stress, symptoms of internalizing mental health problems, and academic performance in a sample of 94 Latino middle school students. Students reported on symptoms indicative of depression and anxiety related problems and acculturative stress. Teachers reported on students' academic…

  8. Altered left ventricular performance in aging physically active mice with an ankle sprain injury.

    Science.gov (United States)

    Turner, Michael J; Guderian, Sophie; Wikstrom, Erik A; Huot, Joshua R; Peck, Bailey D; Arthur, Susan T; Marino, Joseph S; Hubbard-Turner, Tricia

    2016-02-01

    We assessed the impact of differing physical activity levels throughout the lifespan, using a musculoskeletal injury model, on the age-related changes in left ventricular (LV) parameters in active mice. Forty male mice (CBA/J) were randomly placed into one of three running wheel groups (transected CFL group, transected ATFL/CFL group, SHAM group) or a SHAM Sedentary group (SHAMSED). Before surgery and every 6 weeks after surgery, LV parameters were measured under 2.5 % isoflurane inhalation. Group effects for daily distance run was significantly greater for the SHAM and lesser for the ATLF/CFL mice (p = 0.013) with distance run decreasing with age for all mice (p < 0.0001). Beginning at 6 months of age, interaction (group × age) was noted with LV posterior wall thickness-to-radius ratios (h/r) where h/r increased with age in the ATFL/CFL and SHAMSED mice while the SHAM and CFL mice exhibited decreased h/r with age (p = 0.0002). Passive filling velocity (E wave) was significantly greater in the SHAM mice and lowest for the ATFL/CFL and SHAMSED mice (p < 0.0001) beginning at 9 months of age. Active filling velocity (A wave) was not different between groups (p = 0.10). Passive-to-active filling velocity ratio (E/A ratio) was different between groups (p < 0.0001), with higher ratios for the SHAM mice and lower ratios for the ATFL/CFL and SHAMSED mice in response to physical activity beginning at 9 months of age. Passive-to-active filling velocity ratio decreased with age (p < 0.0001). Regular physical activity throughout the lifespan improved LV structure, passive filling velocity, and E/A ratio by 6 to 9 months of age and attenuated any negative alterations throughout the second half of life. The diastolic filling differences were found to be significantly related to the amount of activity performed by 9 months and at the end of the lifespan. PMID:26803818

  9. Neonatal perirhinal lesions in rhesus macaques alter performance on working memory tasks with high proactive interference

    Directory of Open Access Journals (Sweden)

    Alison R Weiss

    2016-01-01

    Full Text Available The lateral prefrontal cortex is known for its contribution to working memory (WM processes in both humans and animals. Yet, recent studies indicate that the prefrontal cortex is part of a broader network of interconnected brain areas involved in WM. Within the medial temporal lobe structures, the perirhinal cortex, which has extensive direct interactions with the lateral and orbital prefrontal cortex, is required to form active/flexible representations of familiar objects. However, its participation in WM processes has not be fully explored. The goal of this study was to assess the effects of neonatal perirhinal lesions on maintenance and monitoring WM processes. As adults, animals with neonatal perirhinal lesions and their matched controls were tested in three object-based (non-spatial WM tasks that tapped different WM processing domains, e.g. maintenance only (Session-unique Delayed-nonmatching-to Sample, SU-DNMS, and maintenance and monitoring (Object-Self-Order, OBJ-SO; Serial Order Memory Task, SOMT. Neonatal perirhinal lesions transiently impaired the acquisition of SU-DNMS at a short (5s delay, but not when re-tested with a longer delay (30s. The same neonatal lesions severely impacted acquisition of OBJ-SO task, and the impairment was characterized by a sharp increase in perseverative errors. By contrast, neonatal perirhinal lesion spared the ability to monitor the temporal order of items in WM as measured by the SOMT. Contrary to the SU-DNMS and OBJ-SO, which re-use the same stimuli across trials and thus produce proactive interference, the SOMT uses novel objects on each trial and is devoid of interference. Therefore, the impairment of monkeys with neonatal perirhinal lesions on SU-DNMS and OBJ-SO tasks is likely to be caused by an inability to solve working memory tasks with high proactive interference. The sparing of performance on the SOMT demonstrates that neonatal perirhinal lesions do not alter working memory processes per se

  10. Deployments, Stress, and Soldiers' Academic Performance

    Science.gov (United States)

    Perot, Mindy

    2012-01-01

    This study focused on identifying whether certain factors affected the academic performance of Soldiers attending an Army educational institution. Academic performance was measured by the grade percentile average of the participant upon the completion of their course of enrollment. Factors that were considered within the study through…

  11. Relationship Between Organizational Climate, Job Stress And Job Performance Officer At State Education Department

    Directory of Open Access Journals (Sweden)

    Turiman Suandi

    2014-01-01

    Full Text Available This research aims at finding out the relationship between Organizational Climate, job stress and job performance among State Education Department (JPN officers . The focus of the research is to determeane the job performance of state education department officers, level of job stress among the officers, level of connection between organizational climate with job stress of State Education Department officers, looking at the difference in level of performance according to demographic factors and looking at the influence of organizational climate and job stress towards job performance . Research findings pertaining level of job performance showed that 75.8% of the respondents are at a high level, 23.7% respondents are at a moderate level while 0.5% respondents are at a low level. For organizational climate, findings show that 79.0% respondents are in the moderate level, 1.6 % respondents are at a highlevel and 19.4% respondents are at a low level. Findings on overall level of job stress found that as many as 92.5% respondents are at a normal job stress. Only about 7.5% respondents are at a moderate level of job stress. There is not even one respondent who are facing a high level of job stress.  In terms of the relationship between independent variables (organizational climate, job stress and dependent variable (job performance, the research findings show that there is a moderate level of positive relationship which is quite significant between organizational climate and job performance of the State Education Department officers at α = 0.01 (p < 0.01; r = 0.396. 

  12. Investigating the effect of job stress and emotional intelligence on job performance

    Directory of Open Access Journals (Sweden)

    Mojtaba Rafiee

    2013-09-01

    Full Text Available Researchers and scholars of management and behavioral sciences have tried to determine effective factors, which influence on efficiency and effectiveness in order to increase organization performance and they have tried to identify factors, which create job stress. In this research, we investigate the effect of job stress on job performance through emotional, organizational and moral intelligence. The study is a descriptive-analytic one, which is based on correlation, uses survey method to gather data and they are analyzed using structural equation modeling. The population of this research includes all the personnel of Registry Organization in Arak city. The results suggest that job stress influences on job performance through organizational intelligence and moral intelligence, but job stress does not influence on job performance through emotional intelligence. Regarding research hypotheses, results and findings after analyzing obtained data suggest that job stress influences on emotional, organizational and moral intelligence, but job stress does not influence on job performance. In addition, the results show that organizational and moral intelligence influence on job performance but emotional intelligence does not influence on job performance.

  13. Pre-spawning parental stress affects channel catfish, Ictalurus punctatus reproduction and subsequent progeny performance

    Science.gov (United States)

    Routine fish handling procedures associated with seining, selecting, transportation, crowding, weighing, and stripping have shown to cause negative physiological responses to hatchery performance. In teleosts, cortisol is the main corticosteroid released during stress, and hence, plasma cortisol co...

  14. Does learning performance in horses relate to fearfulness, baseline stress hormone, and social rank?

    DEFF Research Database (Denmark)

    Christensen, Janne Winther; Ahrendt, Line Peerstrup; Lintrup, Randi;

    2012-01-01

    affect neurons within the hippocampus; a brain region central to learning and memory. In a series of experiments, we aimed to investigate the link between performance in two learning tests, the baseline level of stress hormones, measured as faecal cortisol metabolites (FCM), fearfulness, and social rank...... in the novel environment (e.g. object alertness and final stage: rS = −0.43, P = 0.04), suggesting that performance under unfamiliar, stressful conditions may be predicted by behavioural responses in a fear test. There was a negative correlation between social rank and baseline stress hormones (r......S = −0.43, P = 0.04), i.e. high rank corresponded to low FCM concentrations, whereas neither rank nor FCM correlated with fearfulness or learning performance. We conclude that performance under stressful conditions is affected by activation of the sympathetic nervous system during training and related to...

  15. Effect of heat stress on reproductive performances of dairy cattle and buffaloes: A review

    OpenAIRE

    Soumya Dash; Chakravarty, A. K.; Avtar Singh; Arpan Upadhyay; Manvendra Singh; Saleem Yousuf

    2016-01-01

    Heat stress has adverse effects on the reproductive performances of dairy cattle and buffaloes. The dairy sector is a more vulnerable to global warming and climate change. The temperature humidity index (THI) is the widely used index to measure the magnitude of heat stress in animals. The bjective of this paper was to assess the decline in performances of reproductive traits such as service period, conception rate and pregnancy rate of dairy cattle and buffaloes with respect to increase in TH...

  16. Stress among Medical Students and Its Association with Substance Use and Academic Performance

    OpenAIRE

    Leta Melaku; Andualem Mossie; Alemayehu Negash

    2015-01-01

    Background. Chronic stress among medical students affects academic performance of students and leads to depression, substance use, and suicide. There is, however, a shortage of such research evidence in Ethiopia. Objective. We aimed to estimate the prevalence and severity of stress and its association with substance use and academic performance among medical students. Methods. A cross-sectional survey was conducted on a sample of 329 medical students at Jimma University. Data were collected u...

  17. Relationship between Occupational Stress, Emotional Intelligence and Job Performance: An Empirical Study in Malaysia

    OpenAIRE

    Azman Ismail; Yeo Suh-Suh; Mohd Na’eim Ajis; Noor Faizzah Dollah

    2009-01-01

    This study was conducted to examine the effect of emotional intelligence in the relationship between occupational stress and job performance using 104 usable questionnaires gathered from academic employees who work in private institutions of higher learning in Kuching City, Malaysia. The outcomes of testing research hypothesis using a stepwise regression analysis showed that relationship between occupational stress and emotional intelligence significantly correlated with job performance. Stat...

  18. Investigating the effect of job stress and emotional intelligence on job performance

    OpenAIRE

    Mojtaba Rafiee; Hojat Kazemi; Mustafa Alimiri

    2013-01-01

    Researchers and scholars of management and behavioral sciences have tried to determine effective factors, which influence on efficiency and effectiveness in order to increase organization performance and they have tried to identify factors, which create job stress. In this research, we investigate the effect of job stress on job performance through emotional, organizational and moral intelligence. The study is a descriptive-analytic one, which is based on correlation, uses survey method to ga...

  19. COMT Val158Met genotype selectively alters prefrontal [18F]fallypride displacement and subjective feelings of stress in response to a psychosocial stress challenge.

    Directory of Open Access Journals (Sweden)

    Dennis Hernaus

    Full Text Available Catechol-O-methyltransferase (COMT plays an essential role in degradation of extracellular dopamine in prefrontal regions of the brain. Although a polymorphism in this gene, COMT Val(158Met, affects human behavior in response to stress little is known about its effect on dopaminergic activity associated with the human stress response, which may be of interest for stress-related psychiatric disorders such as psychosis. We aimed to investigate the effect of variations in COMT genotype on in vivo measures of stress-induced prefrontal cortex (PFC dopaminergic processing and subjective stress responses. A combined sample of healthy controls and healthy first-degree relatives of psychosis patients (n = 26 were subjected to an [(18F]fallypride Positron Emission Tomography scan. Psychosocial stress during the scan was induced using the Montreal Imaging Stress Task and subjective stress was assessed every 12 minutes. Parametric t-maps, generated using the linear extension of the simplified reference region model, revealed an effect of COMT genotype on the spatial extent of [(18F]fallypride displacement. Detected effects of exposure to psychosocial stress were unilateral and remained restricted to the left superior and right inferior frontal gyrus, with Met-hetero- and homozygotes showing less [(18F]fallypride displacement than Val-homozygotes. Additionally, Met-hetero- and homozygotes experienced larger subjective stress responses than Val-homozygotes. The direction of the effects remained the same when the data was analyzed separately for controls and first-degree relatives. The human stress response may be mediated in part by COMT-dependent dopaminergic PFC activity, providing speculation for the neurobiology underlying COMT-dependent differences in human behaviour following stress. Implications of these results for stress-related psychopathology and models of dopaminergic functioning are discussed.

  20. COMT Val158Met Genotype Selectively Alters Prefrontal [18F]Fallypride Displacement and Subjective Feelings of Stress in Response to a Psychosocial Stress Challenge

    OpenAIRE

    Dennis Hernaus; Dina Collip; Johan Lataster; Jenny Ceccarini; Gunther Kenis; Linda Booij; Jens Pruessner; Koen Van Laere; Ruud van Winkel; Jim van Os; Inez Myin-Germeys

    2013-01-01

    Catechol-O-methyltransferase (COMT) plays an essential role in degradation of extracellular dopamine in prefrontal regions of the brain. Although a polymorphism in this gene, COMT Val(158)Met, affects human behavior in response to stress little is known about its effect on dopaminergic activity associated with the human stress response, which may be of interest for stress-related psychiatric disorders such as psychosis. We aimed to investigate the effect of variations in COMT genotype on in v...

  1. Explicit Control of Implicit Responses: Simple Directives can alter IAT Performance

    OpenAIRE

    Wallaert, Matthew; Ward, Andrew; Mann, Traci

    2010-01-01

    Research has begun to reveal the malleability of implicit prejudice. One measure of this construct, the race Implicit Association Test (IAT), represents a widely-used tool to assess individuals’ positive and negative associations with different racial groups. In two studies, we demonstrate the capacity of salient pressures to alter implicit racial responses. In Study 1, an enhancement of promoting pressures through an explicit instruction to stereotype was sufficient to increase pro-White bia...

  2. Early Transcriptomic Adaptation to Na2CO3 Stress Altered the Expression of a Quarter of the Total Genes in the Maize Genome and Exhibited Shared and Distinctive Profiles with NaCl and High pH Stresses

    Institute of Scientific and Technical Information of China (English)

    LiMin Zhang; XiangGuo Liu; XinNing Qu; Ying Yu; SiPing Han; Yao Dou; YaoYao Xu; HaiChun Jing; DongYun Hao

    2013-01-01

    Sodium carbonate (Na2CO3) presents a huge challenge to plants by the combined damaging effects of Naþ, high pH, and CO32-. Little is known about the cellular responses to Na2CO3 stress. In this study, the transcriptome of maize (Zea mays L. cv. B73) roots exposed to Na2CO3 stress for 5 h was compared with those of NaCl and NaOH stresses. The expression of 8,319 genes, representing over a quarter of the total number of genes in the maize genome, was altered by Na2CO3 stress, and the downregulated genes (5,232) outnumbered the upregulated genes (3,087). The effects of Na2CO3 differed from those of NaCl and NaOH, primarily by downregulating different categories of genes. Pathways commonly altered by Na2CO3, NaCl, and NaOH were enriched in phenylpropanoid biosynthesis, oxidation of unsaturated fatty acids, ATP-binding cassette (ABC) transporters, as well as the metabolism of secondary metabolites. Genes for brassinosteroid biosynthesis were specifically upregulated by Na2CO3, while genes involved in ascorbate and aldarate metabolism, protein processing in the endoplasmic reticulum and by N-glycosylation, fatty acid biosynthesis, and the circadian rhythm were downregulated. This work provides the first holistic picture of early transcriptomic adaptation to Na2CO3 stress, and highlights potential molecular pathways that could be manipulated to improve tolerance in maize.

  3. The tomato mutant ars1 (altered response to salt stress 1) identifies an R1-type MYB transcription factor involved in stomatal closure under salt acclimation.

    Science.gov (United States)

    Campos, Juan F; Cara, Beatriz; Pérez-Martín, Fernando; Pineda, Benito; Egea, Isabel; Flores, Francisco B; Fernandez-Garcia, Nieves; Capel, Juan; Moreno, Vicente; Angosto, Trinidad; Lozano, Rafael; Bolarin, Maria C

    2016-06-01

    A screening under salt stress conditions of a T-DNA mutant collection of tomato (Solanum lycopersicum L.) led to the identification of the altered response to salt stress 1 (ars1) mutant, which showed a salt-sensitive phenotype. Genetic analysis of the ars1 mutation revealed that a single T-DNA insertion in the ARS1 gene was responsible of the mutant phenotype. ARS1 coded for an R1-MYB type transcription factor and its expression was induced by salinity in leaves. The mutant reduced fruit yield under salt acclimation while in the absence of stress the disruption of ARS1 did not affect this agronomic trait. The stomatal behaviour of ars1 mutant leaves induced higher Na(+) accumulation via the transpiration stream, as the decreases of stomatal conductance and transpiration rate induced by salt stress were markedly lower in the mutant plants. Moreover, the mutation affected stomatal closure in a response mediated by abscisic acid (ABA). The characterization of tomato transgenic lines silencing and overexpressing ARS1 corroborates the role of the gene in regulating the water loss via transpiration under salinity. Together, our results show that ARS1 tomato gene contributes to reduce transpirational water loss under salt stress. Finally, this gene could be interesting for tomato molecular breeding, because its manipulation could lead to improved stress tolerance without yield penalty under optimal culture conditions. PMID:26578112

  4. Enhancing performance and reducing stress in sports technological advances

    CERN Document Server

    Ivancevic, Tijana; Greenberg, Ronald

    2015-01-01

    This book is designed to help athletes and individuals interested in high sports performance in their journey towards the perfection of human sports abilities and achievements. It has two main goals: accelerating the acquisition of motor skills and preparing and vigilantly reducing the recovery time after training and competition. The Diamond Sports Protocol (DSP) presents state-of-the-art techniques for current sport and health technologies, particularly neuromuscular electrical stimulation (Sports Wave), oxygen infusion (Oxy Sports), infrared (Sports Infrared Dome) and lactic acid cleaning (Turbo Sports). The book suggest DSP as an essential part of every future athlete's training, competition and health maintenance. The book is for everyone interested in superior sports performance, fast and effective rehabilitation from training and competition and sports injury prevention.

  5. Stress among Medical Students and Its Association with Substance Use and Academic Performance

    Directory of Open Access Journals (Sweden)

    Leta Melaku

    2015-01-01

    Full Text Available Background. Chronic stress among medical students affects academic performance of students and leads to depression, substance use, and suicide. There is, however, a shortage of such research evidence in Ethiopia. Objective. We aimed to estimate the prevalence and severity of stress and its association with substance use and academic performance among medical students. Methods. A cross-sectional survey was conducted on a sample of 329 medical students at Jimma University. Data were collected using the General Health Questionnaire (GHQ-12, Medical Students Stress Questionnaire (MSSQ-20, and Drug Abuse Surveillance Test (DAST. Data were analyzed using SPSS version 20.0. Logistic regression analysis and Student’s t-test were applied. Results. The mean age of the respondents was 23.02 (SD = 2.074 years. The current prevalence of stress was 52.4%. Academic related stressor domain was the main source of stress among 281 (88.6% students. Stress was significantly associated with khat chewing [AOR = 3.03, 95% CI (1.17, 7.85], smoking [AOR = 4.55, 95% CI (1.05, 19.77], and alcohol intake [AOR = 1.93, 95% CI (1.03, 3.60]. The prevalence of stress was high during the initial three years of study. Stress was significantly (p=0.001 but negatively (r=-0.273 correlated with academic achievement. Conclusion. Stress was a significant problem among medical students and had a negative impact on their academic performance. Year of study, income, and substance use were associated with stress. Counseling and awareness creation are recommended.

  6. Personal and Job Related Predictors of Teacher Stress and Job Performance among School Teachers

    Directory of Open Access Journals (Sweden)

    Rubina Hanif

    2011-12-01

    Full Text Available The present study was conducted to find out role of personal and job related variables in teacher stress and job performance of school teachers. Furthermore, levels and sources of stress and their relationship with job performance among teachers were also explored. The measures used in this study were indigenously developed i.e., Teacher Stress Inventory (TSI-Urdu, Teachers Job Performance Scale and personal and job related Information sheet. Two independent samples were selected from Government and Private Schools of Islamabad (Pakistan. Sample I was comprised of 400 teachers (men and women from Primary and secondary schools. For the evaluation of teachers’ job performance another sample of 1200 students from the classes of teachers of sample I was selected. Three students were randomly selected from each teacher’s class. The students were requested to evaluate their respective teachers’ job performance. The findings revealed that negative significant relationship exists between teachers stress and job performance. The step-wise regression analysis revealed school system, gender, job experience, number of family members, and number of students as significant predictors of teacher stress and gender, school system, family members, job experience and age as significant predictors of teachers’ job performance.

  7. Environmental heat stress enhances mental fatigue during sustained attention task performing: evidence from an ASL perfusion study.

    Science.gov (United States)

    Qian, Shaowen; Li, Min; Li, Guoying; Liu, Kai; Li, Bo; Jiang, Qingjun; Li, Li; Yang, Zhen; Sun, Gang

    2015-03-01

    This study was to investigate the potential enhancing effect of heat stress on mental fatigue progression during sustained attention task using arterial spin labeling (ASL) imaging. Twenty participants underwent two thermal exposures in an environmental chamber: normothermic (NT) condition (25°C, 1h) and hyperthermic (HT) condition (50°C, 1h). After thermal exposure, they performed a twenty-minute psychomotor vigilance test (PVT) in the scanner. Behavioral analysis revealed progressively increasing subjective fatigue ratings and reaction time as PVT progressed. Moreover, heat stress caused worse performance. Perfusion imaging analyses showed significant resting-state cerebral blood flow (CBF) alterations after heat exposure. Specifically, increased CBF mainly gathered in thalamic-brainstem area while decreased CBF predominantly located in fronto-parietal areas, anterior cingulate cortex, posterior cingulate cortex, and medial frontal cortex. More importantly, diverse CBF distributions and trend of changes between both conditions were observed as the fatigue level progressed during subsequent PVT task. Specifically, higher CBF and enhanced rising trend were presented in superior parietal lobe, precuneus, posterior cingulate cortex and anterior cingulate cortex, while lower CBF or inhibited rising trend was found in dorsolateral frontal cortex, medial frontal cortex, inferior parietal lobe and thalamic-brainstem areas. Furthermore, the decrease of post-heat resting-state CBF in fronto-parietal cortex was correlated with subsequent slower reaction time, suggesting prior disturbed resting-state CBF might be indicator of performance potential and fatigue level in following task. These findings may provide proof for such a view: heat stress has a potential fatigue-enhancing effect when individual is performing highly cognition-demanding attention task. PMID:25435315

  8. Pectin May Hinder the Unfolding of Xyloglucan Chains during Cell Deformation: Implications of the Mechanical Performance of Arabidopsis Hypocotyls with Pectin Alterations

    Institute of Scientific and Technical Information of China (English)

    Willie Abasolo; Michaela Eder; Kazuchika Yamauchi; Nicolai Obel; Antje Reinecke; Lutz Neumetzler; John W.C. Dunlop; Gregory Mouille; Markus Pauly; Herman H(o)fte; Ingo Burgert

    2009-01-01

    Plant cell walls, like a multitude of other biological materials, are natural fiber-reinforced composite materials. Their mechanical properties are highly dependent on the interplay of the stiff fibrous phase and the soft matrix phase and on the matrix deformation itself. Using specific Arabidopsis thaliana mutants, we studied the mechanical role of the matrix assembly in primary cell walls of hypocotyls with altered xyloglucan and pectin composition. Standard microtensile tests and cyclic loading protocols were performed on rnurl hypocotyls with affected RGII borate diester cross-links and a hin-dered xyloglucan fucosylation as well as qua2 exhibiting 50% less homogalacturonan in comparison to wild-type. As a con-trol, wild-type plants (Col-0) and tour2 exhibiting a specific xyloglucan fucosylation and no differences in the pectin network were utilized. In the standard tensile tests, the ultimate stress levels (-tensile strength) of the hypocotyls of the mutants with pectin alterations (rnurl, qua2) were rather unaffected, whereas their tensile stiffness was noticeably reduced in comparison to Col-0. The cyclic loading tests indicated a stiffening of all hypocotyls after the first cycle and a plastic deformation during the first straining, the degree of which, however, was much higher for murl and qua2 hypo-cotyls. Based on the mechanical data and current cell wall models, it is assumed that folded xyloglucan chains between cellulose fibrils may tend to unfold during straining of the hypocotyls. This response is probably hindered by geometrical constraints due to pectin rigidity.

  9. Alterations in the activities of the enzymes of proline metabolism in Ragi (Eleusine coracana) leaves during water stress

    OpenAIRE

    Kandpal, Rajendra P; Vaidyanathan, CS; Kumar, Udaya M; Sastry, Krishna KS; Rao, Appaji N.

    1981-01-01

    Free proline content in Ragi (Eleusine coracana) leaves increased markedly (6 to 85 fold) as the degree of water stress, created by polyethylene gylcol treatment, was prolonged There was also a marginal increase in soluble proteins in the stressed leaves as compared to that in the controls. Water stress stimulated the activities of ornithine aminotransferase and pyrroline-5-carboxylate reductase, the enzymes of proline biosynthesis and markedly inhibited the enzymes involved in proline degrad...

  10. Progesterone regulates corticosterone elevation and alterations in spatial memory and exploratory behavior induced by stress in Wistar rats

    OpenAIRE

    Yolanda Diaz-Burke; Claudia Elena Gonzalez-Sandoval; Carlos Eduardo Valencia-Alfonso; Miguel Huerta; Xóchitl Trujillo; Lourdes Diaz; Joaquín García-Estrada; Sonia Luquín

    2010-01-01

    The hippocampus is sensitive to high levels of glucocorticoids during stress responses; it suffers biochemical and cellular changes that affect spatial memory and exploratory behavior, among others. We analyzed the influence of the neurosteroid progesterone (PROG) on stress-induced changes in urinary corticosterone (CORT) levels, spatial memory and exploratory behavior. Castrated adult male rats were implanted with PROG or vehicle (VEHI), and then exposed for ten days to chronic stress create...

  11. Effect of Exercise and Vitamin E on Cardiac Troponin Alterations in Myocardium and Serum of Rats after Stressful Intense Exercise

    OpenAIRE

    N.S. AL-Sowyan

    2010-01-01

    Increased concentrations of biomarkers reflecting myocardial stress such as cardiac troponin have been observed following strenuous exercise. The aim of this study was to determine whether the stress of forced exercise would result in injury to the myocardium. The effects of stress induced by short bout strenuous exercise and long term exercise on serum, cardiac and skeletal muscle troponin, also blood glucose and insulin were measured. Moreover, to determine whether vitamin E supplementation...

  12. Early field performance of drought-stressed scots pine (pinus sylvestris l.) seedlings

    International Nuclear Information System (INIS)

    Scots pine (Pinus sylvestris) has a large natural distribution throughout the world, including semi-arid areas of Turkey, where it is being used for afforestation. Determining the drought resistance of Scots pine provenances can increase the success of afforestation efforts in semi-arid regions. In the first stage of this study, water-stress treatments were applied to ten provenances of one-year-old Scots pine seedlings in their second vegetation period (between April and November). The diameter and height of the seedlings were evaluated in the nursery in order to determine their morphology. The four drought-stress treatments consisted of once-weekly irrigation (IR1), twice-weekly irrigation (IR2-Control), biweekly irrigation (IR3) and open field conditions (IR4). Later, the water-stressed seedlings were planted in a semi-arid district in Bayburt, Turkey, and their survival and growth performances were evaluated over a five-year period. The nursery study showed that drought stress and provenance as well as the interaction of the two significantly affected the morphological characteristics of the seedlings. Under water-stress conditions, the best growth performance was found in the Dokurcun, Degirmendere and Dirgine provenance seedlings. Water-stress and provenance factors and their interaction also affected the open field performance of the seedlings, where the Degirmendere, Dirgine and Dokurcun provenances again exhibited the best performance. Consequently, these Scots pine provenances can be recommended for afforestation sites having conditions similar to those of the study site. (author)

  13. Progesterone regulates corticosterone elevation and alterations in spatial memory and exploratory behavior induced by stress in Wistar rats

    Directory of Open Access Journals (Sweden)

    Yolanda Diaz-Burke

    2010-02-01

    Full Text Available The hippocampus is sensitive to high levels of glucocorticoids during stress responses; it suffers biochemical and cellular changes that affect spatial memory and exploratory behavior, among others. We analyzed the influence of the neurosteroid progesterone (PROG on stress-induced changes in urinary corticosterone (CORT levels, spatial memory and exploratory behavior.Castrated adult male rats were implanted with PROG or vehicle (VEHI,and then exposed for ten days to chronic stress created by overcrowding or ultrasonic noise. PROG and CORT levels were assessed in urine using highperformanceliquid chromatography (HPLC. Implanted PROG inhibited the rise of stress-induced CORT, prevented spatial memory impairment in the Morris water maze, and eliminated increased exploratory behavior in the hole-board test. These results suggest a protective role of PROG, possibly mediated by its anxiolytic mechanisms, against corticosteroids elevation and the behavioral deficit generated by stressful situations.

  14. School Performance, School Segregation, and Stress-Related Symptoms: Comparing Helsinki and Stockholm

    Science.gov (United States)

    Modin, Bitte; Karvonen, Sakari; Rahkonen, Ossi; Östberg, Viveca

    2015-01-01

    This study investigates cross-cultural differences in the interrelation between school performance, school segregation, and stress-related health among 9th-grade students in the greater Stockholm and Helsinki areas. Contrary to the Swedish case, it has been proposed that school performance in Finland is largely independent of the specific school…

  15. Stress.

    Science.gov (United States)

    Chambers, David W

    2008-01-01

    We all experience stress as a regular, and sometimes damaging and sometimes useful, part of our daily lives. In our normal ups and downs, we have our share of exhaustion, despondency, and outrage--matched with their corresponding positive moods. But burnout and workaholism are different. They are chronic, dysfunctional, self-reinforcing, life-shortening habits. Dentists, nurses, teachers, ministers, social workers, and entertainers are especially susceptible to burnout; not because they are hard-working professionals (they tend to be), but because they are caring perfectionists who share control for the success of what they do with others and perform under the scrutiny of their colleagues (they tend to). Workaholics are also trapped in self-sealing cycles, but the elements are ever-receding visions of control and using constant activity as a barrier against facing reality. This essay explores the symptoms, mechanisms, causes, and successful coping strategies for burnout and workaholism. It also takes a look at the general stress response on the physiological level and at some of the damage American society inflicts on itself. PMID:18846841

  16. A Structural Model of Stress, Motivation, and Academic Performance in Medical Students

    Science.gov (United States)

    Park, Jangho; An, Hoyoung; Park, Seungjin; Lee, Chul; Kim, Seong Yoon; Lee, Jae-Dam; Kim, Ki-Soo

    2012-01-01

    Objective The purpose of the present study was 1) to identify factors that may influence academic stress in medical students and 2) to investigate the causal relationships among these variables with path analysis. Methods One hundred sixty medical students participated in the present study. Psychological parameters were assessed with the Medical Stress Scale, Minnesota Multiphasic Personality Inventory, Hamilton Depression Scale, Beck Depression Inventory, and Academic Motivation Scale. Linear regression and path analysis were used to examine the relationships among variables. Results Significant correlations were noted between several factors and Medical Stress scores. Specifically, Hamilton Depression Scale scores (β=0.26, p=0.03) and amotivation (β=0.20, p=0.01) and extrinsically identified regulation (β=0.27, pAcademic Motivation Scale had independent and significant influences on Medical Stress Scale scores. A path analysis model indicated that stress, motivation, and academic performance formed a triangular feedback loop. Moreover, depression was associated with both stress and motivation, and personality was associated with motivation. Conclusion The triangular feedback-loop structure in the present study indicated that actions that promote motivation benefit from interventions against stress and depression. Moreover, stress management increases motivation in students. Therefore, strategies designed to reduce academic pressures in medical students should consider these factors. Additional studies should focus on the relationship between motivation and depression. PMID:22707964

  17. Thermal cycling of stress-induced martensite for high-performance shape memory effect

    International Nuclear Information System (INIS)

    A novel approach to achieve an extraordinary high stress recovery shape memory effect based on thermal cycling of stress-induced martensite is proposed. An alternative thermodynamic path is considered in order to achieve outstanding functional properties of Ni-rich NiTi alloys, which are commonly used at room or body temperature as superelastic materials. Fatigue tests revealed excellent stability of the material subjected to the novel thermomechanical path, confirming its suitability for employment in high-performance shape memory actuators

  18. Monitoring Perceived Stress and Recovery in Relation to Cycling Performance in Female Athletes

    NARCIS (Netherlands)

    Otter, R T A; Brink, M S; van der Does, H T D; Lemmink, K A P M

    2015-01-01

    The purpose was to investigate perceived stress and recovery related to cycling performance of female athletes over one full year. 20 female athletes (age, 27±8 years; ˙VO2max, 50.3±4.6 mL·kg(-1)·min(-1)) were measured 8 times in one year to determine perceived stress and recovery (RESTQ-Sport) in r

  19. Effects of stress on auditors' organizational commitment, job satisfaction, and job performance

    OpenAIRE

    Abolghasem Masihabadi; Alireza Rajaei; Amir Shams Koloukhi; Hossein Parsian

    2015-01-01

    This study was designed to measure the effects of job stress on organizational commitment, job satisfaction, and job performance. A total of 170 questionnaires were distributed among auditors in the audit institutions in Tehran and Mashhad. To test the hypotheses, path analysis and structural equation and regression were employed. The results showed that the job stress had a negative effect on organizational commitment and job satisfaction and there was not a negative correlation between job...

  20. Effects of Escitalopram on a Rat Model of Persistent Stress-Altered Hedonic Activities: Towards a New Understanding of Stress and Depression.

    Science.gov (United States)

    Yang, Szu-Nian; Wang, Ying-Hsiu; Tung, Che-Se; Ko, Chih-Yuan; Liu, Yia-Ping

    2015-12-31

    Chronic mild stress (CMS) paradigm is a model to simulate clinical depression induced by long-term environmental stress. The present study investigated the effects of escitalopram, a specific serotonin reuptake inhibitor (SSRI), on depression-like activities in adult (18 week-old) Sprague-Dawley (SD) rats that underwent a total 8-week CMS. Body weight, locomotor activity and sucrose consumption of the rats were measured under CMS paradigm and following escitalopram treatment. The plasma level of corticosterone was also measured at the end of the experiment. Our results revealed that the CMS program reduced the body weight, but not the locomotor activity of the rats. Adult SD rats consumed less sucrose solution under CMS. However, chronic escitalopram regime (10 mg/kg/day for 4 weeks) appeared not helpful in reversing this CMS effect and, if any, the drug exaggerated anxiety profile of the animals. Unexpectedly, the stressed rats exhibited higher sucrose consumption than non-stressed rats after receiving repeated saline injections. Further, the stressed rats were found to have a higher plasma level of corticosterone after escitalopram treatment. Our results provide an example of the possibility that previously stressed individuals may develop an anti-depression ability that lessens the benefits of intervention with antidepressants. Finally, a separate group of rats that entered the CMS program at 10 week-old were used to examine possible effects of aging to interpret the stress coping ability observed in the 18 week-old rats. The younger rats developed less anti-anhedonia effects under repeated saline injections. The data of the present study provide a different perspective on stress-induced depression and possible interaction with antidepressants. PMID:26717919

  1. Cardiac reactivity and preserved performance under stress: two sides of the same coin?

    Science.gov (United States)

    Pattyn, Nathalie; Mairesse, Olivier; Cortoos, Aisha; Morais, José; Soetens, Eric; Roelands, Bart; van den Nest, Annick; Kolinsky, Régine

    2014-07-01

    In the present experiment, cognitive control under stress was investigated using a real-life paradigm, namely an evaluation flight for military student pilots. The magnitude of cognitive interference on color-word, numerical and emotional Stroop paradigms was studied during a baseline recording and right before the test flight. Cardio-respiratory parameters were simultaneously assessed during rest and the performance of the Stroop tasks. Cognitive data suggested a different speed/accuracy trade-off under stress, and no modulation of the interference effect for color words or numerical stimuli. However, we observed a major increase in error rates for specific emotional stimuli related to the evaluation situation in the stress condition. The increase in cognitive interference from emotional stimuli, expressed as an increase in error rates, was correlated to the decreased cardiac reactivity to challenge in the stress situation. This relationship is discussed in the framework of Sanders' (1983) model of stress and performance. In terms of future research, this link warrants a fruitful lead to be followed for investigating the causal mechanism of performance decrements under the influence of stress. PMID:23528304

  2. Explicit Control of Implicit Responses: Simple Directives can alter IAT Performance.

    Science.gov (United States)

    Wallaert, Matthew; Ward, Andrew; Mann, Traci

    2010-03-01

    Research has begun to reveal the malleability of implicit prejudice. One measure of this construct, the race Implicit Association Test (IAT), represents a widely-used tool to assess individuals' positive and negative associations with different racial groups. In two studies, we demonstrate the capacity of salient pressures to alter implicit racial responses. In Study 1, an enhancement of promoting pressures through an explicit instruction to stereotype was sufficient to increase pro-White bias on the IAT. In Study 2, an enhancement of inhibiting pressures through a simple instruction to avoid stereotyping was sufficient to reduce pro-White bias. Taken together, the studies suggest that implicit prejudice is amenable to voluntary control through the use of simple, direct means. PMID:21769299

  3. Impact of a stress coping strategy on perceived stress levels and performance during a simulated cardiopulmonary resuscitation: a randomized controlled trial

    OpenAIRE

    Hunziker, Sabina; Pagani, Simona; Fasler, Katrin; Tschan, Franziska; Semmer, Norbert K.; Marsch, Stephan

    2013-01-01

    Background Cardiopulmonary resuscitation (CPR) causes significant stress for the rescuers which may cause deficiencies in attention and increase distractibility. This may lead to misjudgements of priorities and delays in CPR performance, which may further increase mental stress (vicious cycle). This study assessed the impact of a task-focusing strategy on perceived stress levels and performance during a simulated CPR scenario. Methods This prospective, randomized-controlled trial was conducte...

  4. Impact of a stress coping strategy on perceived stress levels and performance during a simulated cardiopulmonary resuscitation: a randomized controlled trial

    OpenAIRE

    Hunziker, Sabina; Pagani, Simona; Fasler, Katrin; Tschan, Franziska; Semmer, Norbert K.; Marsch, Stephan

    2013-01-01

    Background Cardiopulmonary resuscitation (CPR) causes significant stress, which may cause deficiencies in attention and increase distractibility. This may lead to misjudgements of priorities and delays in CPR performance, which may further increase mental stress (vicious cycle). This study assessed the impact of a task-focusing strategy on perceived stress levels and performance during a simulated CPR scenario. Methods This prospective, randomized-controlled trial was conduc...

  5. 3xTgAD mice exhibit altered behavior and elevated Aβ after chronic mild social stress

    OpenAIRE

    Rothman, Sarah M.; Herdener, Nathan; Camandola, Simonetta; Texel, Sarah J.; Mughal, Mohamed R.; Cong, Wei-na; Martin, Bronwen; Mattson, Mark P.

    2011-01-01

    Chronic stress may be a risk factor for developing Alzheimer’s disease (AD), but most studies of the effects of stress in models of AD utilize acute adverse stressors of questionable clinical relevance. The goal of this work was to determine how chronic psychosocial stress affects behavioral and pathological outcomes in an animal model of AD, and to elucidate underlying mechanisms. A triple-transgenic mouse model of AD (3xTgAD mice) and nontransgenic control mice were used to test for an affe...

  6. The decrease in histone methyltransferase EZH2 in response to fluid shear stress alters endothelial gene expression and promotes quiescence.

    Science.gov (United States)

    Maleszewska, Monika; Vanchin, Byambasuren; Harmsen, Martin C; Krenning, Guido

    2016-01-01

    High uniform fluid shear stress (FSS) is atheroprotective and preserves the endothelial phenotype and function through activation of downstream mediators such as MAPK7 (Erk5). Endothelial cells respond to FSS thanks to mechanotransduction. However, how the resulting signaling is integrated and resolved at the epigenetic level remains elusive. We hypothesized that Polycomb methyltransferase EZH2 is involved in the effects of FSS in human endothelial cells. We showed that FSS decreases the expression of the Polycomb methyltransferase EZH2. Despite simultaneous activation of MAPK7, MAPK7 pathway does not directly influence the transcription of EZH2. Interestingly though, the knockdown of EZH2 activates the protective MAPK7 signaling in endothelial cells, even in the absence of FSS. To understand the influence of the FSS-decreased expression of EZH2 on endothelial transcriptome, we performed RNA-seq and differential gene expression analysis. We identified candidate groups of genes dependent on both EZH2 and FSS. Among those, Gene Ontology overrepresentation analysis revealed highly significant enrichment of the cell cycle-related genes, suggesting changes in proliferation. Indeed, the depletion of EZH2 strongly inhibited endothelial proliferation, indicating cell cycle arrest. The concomitant decrease in CCNA expression suggests the transition of endothelial cells into a quiescent phenotype. Further bioinformatical analysis suggested TXNIP as a possible mediator between EZH2 and cell cycle-related gene network. Our data show that EZH2 is a FSS-responsive gene. Decreased EZH2 levels enhance the activation of the atheroprotective MAPK7 signaling. Decrease in EZH2 under FSS mediates the decrease in the expression of the network of cell cycle-related genes, which allows the cells to enter quiescence. EZH2 is therefore important for the protective effects of FSS in endothelium. PMID:26416763

  7. Alterations in glucocorticoid negative feedback following maternal Pb, prenatal stress and the combination: A potential biological unifying mechanism for their corresponding disease profiles

    International Nuclear Information System (INIS)

    Combined exposures to maternal lead (Pb) and prenatal stress (PS) can act synergistically to enhance behavioral and neurochemical toxicity in offspring. Maternal Pb itself causes permanent dysfunction of the body's major stress system, the hypothalamic pituitary adrenal (HPA) axis. The current study sought to determine the potential involvement of altered negative glucocorticoid feedback as a mechanistic basis of the effects in rats of maternal Pb (0, 50 or 150 ppm in drinking water beginning 2 mo prior to breeding), prenatal stress (PS; restraint on gestational days 16-17) and combined maternal Pb + PS in 8 mo old male and female offspring. Corticosterone changes were measured over 24 h following an i.p. injection stress containing vehicle or 100 or 300 μg/kg (females) or 100 or 150 μg/kg (males) dexamethasone (DEX). Both Pb and PS prolonged the time course of corticosterone reduction following vehicle injection stress. Pb effects were non-monotonic, with a greater impact at 50 vs. 150 ppm, particularly in males, where further enhancement occurred with PS. In accord with these findings, the efficacy of DEX in suppressing corticosterone was reduced by Pb and Pb + PS in both genders, with Pb efficacy enhanced by PS in females, over the first 6 h post-administration. A marked prolongation of DEX effects was found in males. Thus, Pb, PS and Pb + PS, sometimes additively, produced hypercortisolism in both genders, followed by hypocortisolism in males, consistent with HPA axis dysfunction. These findings may provide a plausible unifying biological mechanism for the reported links between Pb exposure and stress-associated diseases and disorders mediated via the HPA axis, including obesity, hypertension, diabetes, anxiety, schizophrenia and depression. They also suggest broadening of Pb screening programs to pregnant women in high stress environments

  8. Chronic Unpredictable Stress (CUS)-Induced Anxiety and Related Mood Disorders in a Zebrafish Model: Altered Brain Proteome Profile Implicates Mitochondrial Dysfunction

    OpenAIRE

    Sumana Chakravarty; Bommana R Reddy; Sudhakar, Sreesha R.; Sandeep Saxena; Tapatee Das; Vuppalapaty Meghah; Cherukuvada V Brahmendra Swamy; Arvind Kumar; Idris, Mohammed M.

    2013-01-01

    Anxiety and depression are major chronic mood disorders, and the etiopathology for each appears to be repeated exposure to diverse unpredictable stress factors. Most of the studies on anxiety and related mood disorders are performed in rodents, and a good model is chronic unpredictable stress (CUS). In this study, we have attempted to understand the molecular basis of the neuroglial and behavioral changes underlying CUS-induced mood disorders in the simplest vertebrate model, the zebrafish, D...

  9. A RANDOMIZED CONTROLLED TRIAL ON THE EFFICACY OF MEDHYA RASAYANA TABLET ON ACADEMIC STRESS AND PERFORMANCE IN SCHOOL CHILDREN

    OpenAIRE

    Abhimanyu Kumar; Reena Kulkarni

    2013-01-01

    Background:School children and academics are not exempted from stress. In Indian context, especially for high school children, the demands to be placed high, parental pressures, the future career option and time bound targets along with inherent biological variations of adolescence create paramount stress. Such stress can be detrimental if not well managed. Despite of loss of lives consequent upon stress and poor performance, academic stress is less researched. Psychotherapy is the current go...

  10. Early Adolescence as a Critical Window During Which Social Stress Distinctly Alters Behavior and Brain Norepinephrine Activity

    OpenAIRE

    Bingham, Brian; McFadden, Kile; Zhang, Xiaoyan; Bhatnagar, Seema; Beck, Sheryl; Valentino, Rita

    2010-01-01

    Many neural programs that shape behavior become established during adolescence. Adverse events at this age can have enduring consequences for both adolescent and adult mental health. Here we show that repeated social stress at different stages of adolescent development differentially affects rat behavior and neuronal activity. Early-adolescent (PND 28, EA), mid-adolescent (PND 42, MA), and adult (PND 63) rats were subjected to resident-intruder social stress (7 days) and behavior was examined...

  11. Psychological stress alters the ultrastructure and increases IL-1β and TNF-α in mandibular condylar cartilage

    Directory of Open Access Journals (Sweden)

    Xin Lv

    2012-10-01

    Full Text Available Psychological factors can be correlated with temporomandibular disorders (TMDs, but the mechanisms are unknown. In the present study, we examined the microstructural changes and expression of proinflammatory cytokines in mandibular condylar cartilage of the temporomandibular joint (TMJ in a psychological stress animal model. Male Sprague-Dawley rats (8 weeks old, 210 ± 10 g were randomly divided into 3 groups: psychological stress (PS, N = 48, foot shock (FS, N = 24, and control (N = 48. After inducing psychological stress using a communication box with the FS rats for 1, 3, or 5 weeks, PS rats were sacrificed and compared to their matched control littermates, which received no stress and were killed at the same times as the PS rats. Body and adrenal gland weight were measured and corticosterone and adrenocorticotropic hormone levels were determined by radioimmunoassay. After hematoxylin-eosin staining for histological observation, the ultrastructure of the TMJ was examined by scanning electron microscopy. Transcription and protein levels of interleukin-1β (IL-1β and tumor necrosis factor-α (TNF-α were evaluated by ELISA and semi-quantitative RT-PCR. The PS group showed a significantly higher adrenal gland weight after 3 weeks of stress and higher hormone levels at weeks 1, 3, and 5. Histopathological changes and thinning cartilage were apparent at weeks 3 and 5. In the PS group, TNF-α increased at 1, 3, and 5 weeks and IL-1β increased significantly after 1 and 3 weeks of stress, and then decreased to normal levels by 5 weeks. Psychological stress increased plasma hormone levels and RT-PCR indicated increased IL-1β and TNF-α expression in the TMJ in a time-dependent manner. These results suggest that cytokine up-regulation was accompanied by stress-induced cartilage degeneration in the mandibular condyle. The proinflammatory cytokines play a potential role in initiating the cartilage destruction that eventually leads to the TMDs.

  12. Alterations in polyribosome and messenger ribonucleic acid metabolism and messenger ribonucleoprotein utilization in osmotically stressed plant seedlings

    International Nuclear Information System (INIS)

    Polyribosome aggregation state in growing tissues of barley and wheat leaf of stems of pea and squash was studied in relation to seedling growth and water status of the growing tissue in plants at various levels of osmotic stress. It was found to be highly correlated with water potential and osmotic potential of the growing tissue and with leaf of stem elongation rate. Stress rapidly reduced polyribosome content and water status in growing tissues of barley leaves; changes were slow and slight in the non-growing leaf blade. Membrane-bound and free polyribosomes were equally sensitive to stress-induced disaggregation. Incorporation of 32PO43- into ribosomal RNA was rapidly inhibited by stress, but stability of poly(A)+RNA relative to ribosomal RNA was similar in stressed and unstressed tissues, with a half-life of about 12 hours. Stress also caused progressive loss of poly(A)+RNA from these tissues. Quantitation of poly(A) and in vitro messenger template activity in polysome gradient fractions showed a shift of activity from the polysomal region to the region of 20-60 S in stressed plants. Messenger RNA in the 20-60 S region coded for the same peptides as mRNA found in the polysomal fraction. Nonpolysomal and polysome-derived messenger ribonucleoprotein complexes (mRNP) were isolated, and characteristic proteins were found associated with either fraction. Polysomal mRNP from stressed or unstressed plants were translated with similar efficiency in a wheat germ cell-free system. It was concluded that no translational inhibitory activity was associated with nonpolysomal mRNP from barley prepared as described

  13. Psychological stress alters the ultrastructure and increases IL-1β and TNF-α in mandibular condylar cartilage

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Xin; Li, Qiang; Wu, Shun; Sun, Jing; Zhang, Min; Chen, Yong-Jin [Department of General Dentistry and Emergency, School of Stomatology, Fourth Military Medical University, Xi' an, Shaanxi (China)

    2012-06-22

    Psychological factors can be correlated with temporomandibular disorders (TMDs), but the mechanisms are unknown. In the present study, we examined the microstructural changes and expression of proinflammatory cytokines in mandibular condylar cartilage of the temporomandibular joint (TMJ) in a psychological stress animal model. Male Sprague-Dawley rats (8 weeks old, 210 ± 10 g) were randomly divided into 3 groups: psychological stress (PS, N = 48), foot shock (FS, N = 24), and control (N = 48). After inducing psychological stress using a communication box with the FS rats for 1, 3, or 5 weeks, PS rats were sacrificed and compared to their matched control littermates, which received no stress and were killed at the same times as the PS rats. Body and adrenal gland weight were measured and corticosterone and adrenocorticotropic hormone levels were determined by radioimmunoassay. After hematoxylin-eosin staining for histological observation, the ultrastructure of the TMJ was examined by scanning electron microscopy. Transcription and protein levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were evaluated by ELISA and semi-quantitative RT-PCR. The PS group showed a significantly higher adrenal gland weight after 3 weeks of stress and higher hormone levels at weeks 1, 3, and 5. Histopathological changes and thinning cartilage were apparent at weeks 3 and 5. In the PS group, TNF-α increased at 1, 3, and 5 weeks and IL-1β increased significantly after 1 and 3 weeks of stress, and then decreased to normal levels by 5 weeks. Psychological stress increased plasma hormone levels and RT-PCR indicated increased IL-1β and TNF-α expression in the TMJ in a time-dependent manner. These results suggest that cytokine up-regulation was accompanied by stress-induced cartilage degeneration in the mandibular condyle. The proinflammatory cytokines play a potential role in initiating the cartilage destruction that eventually leads to the TMDs.

  14. Psychological stress alters the ultrastructure and increases IL-1β and TNF-α in mandibular condylar cartilage

    International Nuclear Information System (INIS)

    Psychological factors can be correlated with temporomandibular disorders (TMDs), but the mechanisms are unknown. In the present study, we examined the microstructural changes and expression of proinflammatory cytokines in mandibular condylar cartilage of the temporomandibular joint (TMJ) in a psychological stress animal model. Male Sprague-Dawley rats (8 weeks old, 210 ± 10 g) were randomly divided into 3 groups: psychological stress (PS, N = 48), foot shock (FS, N = 24), and control (N = 48). After inducing psychological stress using a communication box with the FS rats for 1, 3, or 5 weeks, PS rats were sacrificed and compared to their matched control littermates, which received no stress and were killed at the same times as the PS rats. Body and adrenal gland weight were measured and corticosterone and adrenocorticotropic hormone levels were determined by radioimmunoassay. After hematoxylin-eosin staining for histological observation, the ultrastructure of the TMJ was examined by scanning electron microscopy. Transcription and protein levels of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were evaluated by ELISA and semi-quantitative RT-PCR. The PS group showed a significantly higher adrenal gland weight after 3 weeks of stress and higher hormone levels at weeks 1, 3, and 5. Histopathological changes and thinning cartilage were apparent at weeks 3 and 5. In the PS group, TNF-α increased at 1, 3, and 5 weeks and IL-1β increased significantly after 1 and 3 weeks of stress, and then decreased to normal levels by 5 weeks. Psychological stress increased plasma hormone levels and RT-PCR indicated increased IL-1β and TNF-α expression in the TMJ in a time-dependent manner. These results suggest that cytokine up-regulation was accompanied by stress-induced cartilage degeneration in the mandibular condyle. The proinflammatory cytokines play a potential role in initiating the cartilage destruction that eventually leads to the TMDs

  15. Differential relations between youth internalizing/externalizing problems and cortisol responses to performance vs. interpersonal stress.

    Science.gov (United States)

    Laurent, Heidemarie; Vergara-Lopez, Chrystal; Stroud, Laura R

    2016-09-01

    Efforts to define hypothalamic-pituitary-adrenal (HPA) axis profiles conferring risk for psychopathology have yielded inconclusive results, perhaps in part due to limited assessment of the stress response. In particular, research has typically focused on HPA responses to performance tasks, while neglecting the interpersonal stressors that become salient during adolescence. In this study we investigated links between psychosocial adjustment - youth internalizing and externalizing problems, as well as competence - and HPA responses to both performance and interpersonal stressors in a normative sample of children and adolescents. Participants (n = 59) completed a set of performance (public speaking, mental arithmetic, mirror tracing) and/or interpersonal (peer rejection) tasks and gave nine saliva samples, which were assayed for cortisol. Hierarchical linear models of cortisol response trajectories in relation to child behavior checklist (CBCL) scores revealed stressor- and sex-specific associations. Whereas internalizing problems related to earlier peaking, less dynamic cortisol responses to interpersonal stress (across males and females), externalizing problems related to lower, earlier peaking and less dynamic cortisol responses to performance stress for males only, and competence-related to later peaking cortisol responses to interpersonal stress for females only. Implications for understanding contextual stress profiles underlying different forms of psychopathology are discussed. PMID:27470923

  16. Multiple abiotic stress tolerance in Vigna mungo is altered by overexpression of ALDRXV4 gene via reactive carbonyl detoxification.

    Science.gov (United States)

    Singh, Preeti; Kumar, Deepak; Sarin, Neera Bhalla

    2016-06-01

    Vigna mungo (blackgram) is an important leguminous pulse crop, which is grown for its protein rich edible seeds. Drought and salinity are the major abiotic stresses which adversely affect the growth and productivity of crop plants including blackgram. The ALDRXV4 belongs to the aldo-keto reductase superfamily of enzymes that catalyze the reduction of carbonyl metabolites in the cells and plays an important role in the osmoprotection and detoxification of the reactive carbonyl species. In the present study, we developed transgenic plants of V. mungo using Agrobacterium mediated transformation. The transgene integration was confirmed by Southern blot analysis whereas the expression was confirmed by RT-PCR, Western blot and enzyme activity. The T1 generation transgenic plants displayed improved tolerance to various environmental stresses, including drought, salt, methyl viologen and H2O2 induced oxidative stress. The increased aldose reductase activity, higher sorbitol content and less accumulation of the toxic metabolite, methylglyoxal in the transgenic lines under non-stress and stress (drought and salinity) conditions resulted in increased protection through maintenance of better photosynthetic efficiency, higher relative water content and less photooxidative damage. The accumulation of reactive oxygen species was remarkably decreased in the transgenic lines as compared with the wild type plants. This study of engineering multiple stress tolerance in blackgram, is the first report to date and this strategy for trait improvement is proposed to provide a novel germplasm for blackgram production on marginal lands. PMID:26956699

  17. Stress Alters the Discriminative Stimulus and Response Rate Effects of Cocaine Differentially in Lewis and Fischer Inbred Rats

    Directory of Open Access Journals (Sweden)

    Therese A. Kosten

    2012-03-01

    Full Text Available Stress enhances the behavioral effects of cocaine, perhaps via hypothalamic-pituitary-adrenal (HPA axis activity. Yet, compared to Fischer 344 (F344 rats, Lewis rats have hyporesponsive HPA axis function and more readily acquire cocaine self-administration. We hypothesized that stress would differentially affect cocaine behaviors in these strains. The effects of three stressors on the discriminative stimulus and response rate effects of cocaine were investigated. Rats of both strains were trained to discriminate cocaine (10 mg/kg from saline using a two-lever, food-reinforced (FR10 procedure. Immediately prior to cumulative dose (1, 3, 10 mg/kg cocaine test sessions, rats were restrained for 15-min, had 15-min of footshock in a distinct context, or were placed in the shock-paired context. Another set of F344 and Lewis rats were tested similarly except they received vehicle injections to test if stress substituted for cocaine. Most vehicle-tested rats failed to respond after stressor exposures. Among cocaine-tested rats, restraint stress enhanced cocaine’s discriminative stimulus effects in F344 rats. Shock and shock-context increased response rates in Lewis rats. Stress-induced increases in corticosterone levels showed strain differences but did not correlate with behavior. These data suggest that the behavioral effects of cocaine can be differentially affected by stress in a strain-selective manner.

  18. Trivers-Willard hypothesis revisited:Does heat stress peri-insemination alter secondary sex ratio in crossbred dairy cattle?

    Institute of Scientific and Technical Information of China (English)

    FA Khan; SSD Sacchan; MP Singh; RA Patoo; Shiv Prasad; HP Gupta

    2013-01-01

    Objective: To test the hypothesis that heat stress peri-insemination skews towards female the secondary sex ratio in dairy cattle. In addition, the effect of heat stress peri-insemination on birth weight of resultant calves was investigated. Methods: Data on the date of insemination and sex and birth weight of the resultant calf were collected for a total of 934 single births on a crossbred dairy farm and grouped into thermoneutral and heat stress peri-insemination groups on the basis of temperature humidity indices on the day of insemination. Results: Logistic regression revealed no difference in the secondary sex ratios between thermoneutral (53.4:46.6) and heat stress (52.5:47.5) peri-insemination groups. These sex ratios were not different from the expected 50:50 ratio on Chi-square goodness of fit test. Differences in birth weight of calves between thermoneutral and heat stress peri-insemination groups did not approach statistical significance.Conclusions: These results indicate that heat stress peri-insemination does not affect secondary sex ratio and calf birth weight in crossbred dairy cattle.

  19. Elevated temperature altered photosynthetic products in wheat seedlings and organic compounds and biological activity in rhizopshere soil under cadmium stress

    Science.gov (United States)

    Jia, Xia; Zhao, Yonghua; Wang, Wenke; He, Yunhua

    2015-09-01

    The objective of this study was to investigate the effects of slightly elevated atmospheric temperature in the spring on photosynthetic products in wheat seedlings and on organic compounds and biological activity in rhizosphere soil under cadmium (Cd) stress. Elevated temperature was associated with increased soluble sugars, reducing sugars, starch, and total sugars, and with decreased amino acids in wheat seedlings under Cd stress. Elevated temperature improved total soluble sugars, free amino acids, soluble phenolic acids, and organic acids in rhizosphere soil under Cd stress. The activity of amylase, phenol oxidase, invertase, β-glucosidase, and L-asparaginase in rhizosphere soil was significantly improved by elevated temperature under Cd stress; while cellulase, neutral phosphatase, and urease activity significantly decreased. Elevated temperature significantly improved bacteria, fungi, actinomycetes, and total microorganisms abundance and fluorescein diacetate activity under Cd stress. In conclusion, slightly elevated atmospheric temperature in the spring improved the carbohydrate levels in wheat seedlings and organic compounds and biological activity in rhizosphere soil under Cd stress in the short term. In addition, elevated atmospheric temperature in the spring stimulated available Cd by affecting pH, DOC, phenolic acids, and organic acids in rhizosphere soil, which resulted in the improvement of the Cd uptake by wheat seedlings.

  20. Prozac Alters Reproductive Performance and Filial Cannibalism in Male Fighting Fish, Betta Splendens

    Directory of Open Access Journals (Sweden)

    Mohammad Navid Forsatkar

    2014-09-01

    Full Text Available Background: Fluoxetine (ProzacTM is one of the most popular antidepressant that can be released to aquatic systems via sewage-treatment effluents. It is suspected to provoke substantial effects in the aquatic environment. Methods: In spawning tanks, specimens were exposed to concentrations of 0 and 0.54 µgl-1 fluoxetine from male introduction until the larvae had hatched. Prior to spawning, nest area and time spent for nest building were measured. Also, spawning duration, number of copulations per spawning and eggs per copulation, total produced eggs and hatching rate were recorded. Results: The number of copulations, eggs per copulation and total produced eggs did not differ between the two treatments. Fluoxetine treatment significantly decreased the nest size, time spent for nest building and spawning duration. Also hatching rate was significantly lower during fluoxetine treatment than in the control condition. Notably, five fluoxetine treated males cannibalized their eggs and larvae. Conclusion: We showed that environmental exposure of fighting fish to fluoxetine potentially alters specific aspects of nest building and sexual behavior and, as a consequence, reproductive output.

  1. Non-conscious visual cues related to affect and action alter perception of effort and endurance performance

    Directory of Open Access Journals (Sweden)

    Anthony William Blanchfield

    2014-12-01

    Full Text Available The psychobiological model of endurance performance proposes that endurance performance is determined by a decision-making process based on perception of effort and potential motivation. Recent research has reported that effort-based decision-making during cognitive tasks can be altered by non-conscious visual cues relating to affect and action. The effect of these non-conscious visual cues on effort and performance during physical tasks is however unknown. We report two experiments investigating the effect of subliminal priming with visual cues related to affect and action on perception of effort and endurance performance. In Experiment 1 thirteen individuals were subliminally primed with happy or sad faces as they cycled to exhaustion in a counterbalanced and randomized crossover design. A paired t-test (happy vs. sad faces revealed that individuals cycled for significantly longer (178 s, p = .04 when subliminally primed with happy faces. A 2 x 5 (condition x iso-time ANOVA also revealed a significant main effect of condition on rating of perceived exertion (RPE during the time to exhaustion (TTE test with lower RPE when subjects were subliminally primed with happy faces (p = .04. In Experiment 2, a single-subject randomization tests design found that subliminal priming with action words facilitated a significantly longer (399 s, p = .04 TTE in comparison to inaction words (p = .04. Like Experiment 1, this greater TTE was accompanied by a significantly lower RPE (p = .03. These experiments are the first to show that subliminal visual cues relating to affect and action can alter perception of effort and endurance performance. Non-conscious visual cues may therefore influence the effort-based decision-making process that is proposed to determine endurance performance. Accordingly, the findings raise notable implications for individuals who may encounter such visual cues during endurance competitions, training, or health related exercise.

  2. Study of the stress proteins secreted by Leishmania donovani after treatment with edelfosine, mitelfosine and ilmofosine, and morphological alterations analyzed by electronic microscopy

    Directory of Open Access Journals (Sweden)

    Azzouz S.

    2009-09-01

    Full Text Available We studied the stress proteins induced in protozoa Leishmania donovani after treatment with edelfosine, miltefosine and ilmofosine. We studied the morphological and structural modifications caused in the promastigote forms of the parasite after treatment with the three alkyl-lysophospholipids (ALPs. A resistant strain of L. donovani to miltefosine was obtained and the morphological modifications were observed. The stress proteins induction was studied in promastigote forms and also in amastigote-like forms obtained in vitro. The proteins synthesized with the three alkyl-lysophospholipids were compared to those obtained by heat shock. The axenic amastigote forms synthesized a pattern of different proteins for those observed in the promastigote forms. The morphological alterations were observed under electronic microscopy. The membrane and mitochondria were the organs most affected by the three ALPs. We noted an apparition of vacuoles and vesicles in the treated promastigotes. In the resistant strain, we noted myelin bodies in the treated and untreated parasites.

  3. Lipopolysaccharide-Induced Behavioral Alterations Are Alleviated by Sodium Phenylbutyrate via Attenuation of Oxidative Stress and Neuroinflammatory Cascade.

    Science.gov (United States)

    Jangra, Ashok; Sriram, Chandra Shaker; Lahkar, Mangala

    2016-08-01

    Oxido-nitrosative stress, neuroinflammation, and reduced level of neurotrophins are implicated in the pathophysiology of anxiety and depressive illness. A few recent studies have revealed the role of endoplasmic reticulum (ER) stress in the pathophysiology of stress and depression. The aim of the present study is to investigate the neuroprotective potential of sodium phenylbutyrate (SPB), an ER stress inhibitor against lipopolysaccharide (LPS)-induced anxiety and depressive-like behavior in Swiss albino mice. Anxiety and depressive-like behavior was induced by LPS (0.83 mg/kg; i.p.) administration. Various behavioral tests were conducted to evaluate the anxiety and depressive-like behavior in mice. Real-time PCR was employed for the detection and expression of ER stress markers (78-kDa glucose-regulated protein (GRP78) and CCAAT/enhancer binding protein homologous protein (CHOP)). Pretreatment with SPB significantly ameliorated the LPS-induced anxiety and depressive-like behavior as revealed by behavioral paradigm results. LPS-induced oxidative stress was ameliorated by SPB pretreatment in hippocampus (HC) and prefrontal cortex (PFC) region. Neuroinflammation was significantly reduced by SPB pretreatment in LPS-treated mice as evident from reduction in proinflammatory cytokines (IL-1β and TNF-α). Importantly, LPS administration significantly up-regulated the GRP78 mRNA expression level in the HC which suggests the involvement of unfolded protein response (UPR) in LPS-evoked behavioral anomalies. These results highlight the neuroprotective potential of SPB in LPS-induced anxiety and depressive illness model which may be partially due to inhibition of oxidative stress-neuroinflammatory cascade. PMID:27192986

  4. Brain white matter microstructure alterations in adolescent rhesus monkeys exposed to early life stress: associations with high cortisol during infancy

    OpenAIRE

    Howell, Brittany R.; McCormack, Kai M.; GRAND, ALISON P.; Sawyer, Nikki T.; Zhang, Xiaodong; Maestripieri, Dario; Hu, Xiaoping; Sanchez, Mar M.

    2013-01-01

    Background Early adverse experiences, especially those involving disruption of the mother-infant relationship, are detrimental for proper socioemotional development in primates. Humans with histories of childhood maltreatment are at high risk for developing psychopathologies including depression, anxiety, substance abuse, and behavioral disorders. However, the underlying neurodevelopmental alterations are not well understood. Here we used a nonhuman primate animal model of infant maltreatment...

  5. Soybean seed phenol, lignin, and isoflavones and sugars composition are altered by Foliar Boron application in soybean under water stress

    Science.gov (United States)

    Previous research showed that foliar boron (B) fertilizer at flowering or seed-fill growth stages altered seed protein, oil, and fatty acids. The objective of this research was to investigate the effects of foliar B fertilizer on seed phenolics (phenol, lignin, and isoflavones) and sugars concentrat...

  6. The APP670/671 mutation alters calcium signaling and response to hyperosmotic stress in rat primary hippocampal neurons

    DEFF Research Database (Denmark)

    Kloskowska, Ewa; Bruton, Joseph D; Winblad, Bengt; Benedikz, Eirikur

    2008-01-01

    Altered calcium homeostasis is implicated in the pathogenesis of Alzheimer's disease and much effort has been put into understanding the association between the autosomal dominant gene mutations causative of this devastating disease and perturbed calcium signaling. We have focused our attention o...

  7. Metallothionein-I plus II and receptor megalin are altered in relation to oxidative stress in cerebral lymphomas

    DEFF Research Database (Denmark)

    Pedersen, M.O.; Hansen, P.B.; Nielsen, Signe Ledou;

    2010-01-01

    CNS lymphoma). We show for the first time that MT-I + II and megalin are significantly altered in CNS lymphoma relative to controls (reactive lymph nodes and non-lymphoma brain tissue with neuropathology). MT-I + II are secreted in the CNS and are found mainly in the lymphomatous cells, while their...

  8. Angiotensin II type 1 receptors and systemic hemodynamic and renal responses to stress and altered blood volume in conscious rabbits

    Directory of Open Access Journals (Sweden)

    RogerGeorgeEvans

    2011-07-01

    Full Text Available We examined how systemic blockade of type 1 angiotensin (AT1- receptors affects reflex control of the circulation and the kidney. In conscious rabbits, the effects of candesartan on responses of systemic and renal hemodynamics and renal excretory function to acute hypoxia, mild hemorrhage and plasma volume expansion were tested. Candesartan reduced resting mean arterial pressure (MAP, -8 ± 2% without significantly altering cardiac output (CO, increased renal blood flow (RBF, +38 ± 9% and reduced renal vascular resistance (RVR, -32 ± 6%. Glomerular filtration rate (GFR was not significantly altered but sodium excretion (UNa+V increased four-fold. After vehicle treatment, hypoxia (10% inspired O2 for 30 min did not significantly alter MAP or CO, but reduced HR (-17 ± 6%, increased RVR (+33 ± 16% and reduced GFR (-46 ± 16% and UNa+V (-41 ± 17%. Candesartan did not significantly alter these responses. After vehicle treatment, plasma volume expansion increased CO (+35 ± 7%, reduced total peripheral resistance (TPR, -26 ± 5%, increased RBF (+62 ± 23% and reduced RVR (-32 ± 9%, but did not significantly alter MAP or HR. It also increased UNa+V (803 ± 184% yet reduced GFR (-47 ± 9%. Candesartan did not significantly alter these responses. After vehicle treatment, mild hemorrhage did not significantly alter MAP but increased HR (+16 ± 3%, reduced CO (-16 ± 4% and RBF (-18 ± 6%, increased TPR (+18 ± 4% and tended to increase RVR (+18 ± 9%, P = 0.1, but had little effect on GFR or UNa+V. But after candesartan treatment MAP fell during hemorrhage (-19 ± 1%, while neither TPR nor RVR increased, and GFR (-64 ± 18% and UNa+V (-83 ± 10% fell. AT1-receptor activation supports MAP and GFR during hypovolemia. But AT1-receptors appear to play little role in the renal vasoconstriction, hypofiltration and antinatriuresis accompanying hypoxia, or the systemic and renal vasodilatation and natriuresis accompanying plasma volume expansion.

  9. Alteration of cell-wall porosity is involved in osmotic stress-induced enhancement of aluminium resistance in common bean (Phaseolus vulgaris L.).

    Science.gov (United States)

    Yang, Zhong-Bao; Eticha, Dejene; Rao, Idupulapati Madhusudana; Horst, Walter Johannes

    2010-07-01

    Aluminium (Al) toxicity and drought are the two major abiotic stress factors limiting common bean production in the tropics. Using hydroponics, the short-term effects of combined Al toxicity and drought stress on root growth and Al uptake into the root apex were investigated. In the presence of Al stress, PEG 6000 (polyethylene glycol)-induced osmotic (drought) stress led to the amelioration of Al-induced inhibition of root elongation in the Al-sensitive genotype VAX 1. PEG 6000 (> PEG 1000) treatment greatly decreased Al accumulation in the 1 cm root apices even when the roots were physically separated from the PEG solution using dialysis membrane tubes. Upon removal of PEG from the treatment solution, the root tips recovered from osmotic stress and the Al accumulation capacity was quickly restored. The PEG-induced reduction of Al accumulation was not due to a lower phytotoxic Al concentration in the treatment solution, reduced negativity of the root apoplast, or to enhanced citrate exudation. Also cell-wall (CW) material isolated from PEG-treated roots showed a low Al-binding capacity which, however, was restored after destroying the physical structure of the CW. The comparison of the Al(3+), La(3+), Sr(2+), and Rb(+) binding capacity of the intact root tips and the isolated CW revealed the specificity of the PEG 6000 effect for Al. This could be due to the higher hydrated ionic radius of Al(3+) compared with other cations (Al(3+) > La(3+) > Sr(2+) > Rb(+)). In conclusion, the results provide circumstantial evidence that the osmotic stress-inhibited Al accumulation in root apices and thus reduced Al-induced inhibition of root elongation in the Al-sensitive genotype VAX 1 is related to the alteration of CW porosity resulting from PEG 6000-induced dehydration of the root apoplast. PMID:20511277

  10. Constitutive Expression of Rice MicroRNA528 Alters Plant Development and Enhances Tolerance to Salinity Stress and Nitrogen Starvation in Creeping Bentgrass.

    Science.gov (United States)

    Yuan, Shuangrong; Li, Zhigang; Li, Dayong; Yuan, Ning; Hu, Qian; Luo, Hong

    2015-09-01

    MicroRNA528 (miR528) is a conserved monocot-specific small RNA that has the potential of mediating multiple stress responses. So far, however, experimental functional studies of miR528 are lacking. Here, we report that overexpression of a rice (Oryza sativa) miR528 (Osa-miR528) in transgenic creeping bentgrass (Agrostis stolonifera) alters plant development and improves plant salt stress and nitrogen (N) deficiency tolerance. Morphologically, miR528-overexpressing transgenic plants display shortened internodes, increased tiller number, and upright growth. Improved salt stress resistance is associated with increased water retention, cell membrane integrity, chlorophyll content, capacity for maintaining potassium homeostasis, CATALASE activity, and reduced ASCORBIC ACID OXIDASE (AAO) activity; while enhanced tolerance to N deficiency is associated with increased biomass, total N accumulation and chlorophyll synthesis, nitrite reductase activity, and reduced AAO activity. In addition, AsAAO and COPPER ION BINDING PROTEIN1 are identified as two putative targets of miR528 in creeping bentgrass. Both of them respond to salinity and N starvation and are significantly down-regulated in miR528-overexpressing transgenics. Our data establish a key role that miR528 plays in modulating plant growth and development and in the plant response to salinity and N deficiency and indicate the potential of manipulating miR528 in improving plant abiotic stress resistance. PMID:26224802

  11. Performances of carbon nanotube field effect transistors with altered channel length

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The influence of channel length on the performances of carbon nanotube field effect transistors(CNT-FETs) has been studied.Buffered oxide etching was used to remove approximately a 60 nm layer from the original 100 nm silicon dioxide layer,to thin the dielectric layer of the back gate.Channel length of the CNT-FETs was changed along with the etching process.The dependence of drain-source current on gate voltage was measured to analyze the performance of the CNT-FETs,including the transconductance,carrier mobility,current ON/OFF ratio,etc.The results indicate that the devices still keep good quality.

  12. The Effects of Altering Environmental and Instrumental Context on the Performance of Memorized Music

    Science.gov (United States)

    Mishra, Jennifer; Backlin, William

    2007-01-01

    Three experiments investigated whether musical memory was context dependent. Instrumental musicians memorized music in one context and recalled in either the same or a different context. Contexts included atypical performing environments (Experiment 1: lobby/conference room) or commonly encountered environments (Experiment 2: practice room,…

  13. Chromium supplementation alters the performance, metabolism, and immune response of feedlot cattle during the receiving period

    Science.gov (United States)

    Crossbreed steers (n = 180; 507 +/- 13 lb) were fed during a 56-d receiving period to determine if supplementing chromium (Cr; KemTRACEbrandChromiumPropionate 0.04%, Kemin Industries) would improve feedlot performance and health of newly received cattle. A completely randomized block design (36 pens...

  14. Alterations of motor performance and brain cortex mitochondrial function during ethanol hangover.

    Science.gov (United States)

    Bustamante, Juanita; Karadayian, Analia G; Lores-Arnaiz, Silvia; Cutrera, Rodolfo A

    2012-08-01

    Ethanol has been known to affect various behavioral parameters in experimental animals, even several hours after ethanol (EtOH) is absent from blood circulation, in the period known as hangover. The aim of this study was to assess the effects of acute ethanol hangover on motor performance in association with the brain cortex energetic metabolism. Evaluation of motor performance and brain cortex mitochondrial function during alcohol hangover was performed in mice 6 hours after a high ethanol dose (hangover onset). Animals were injected i.p. either with saline (control group) or with ethanol (3.8 g/kg BW) (hangover group). Ethanol hangover group showed a bad motor performance compared with control animals (p hangover animals showed a 34% decrease in the respiratory control rate as compared with the control group. Mitochondrial complex activities were decreased being the complex I-III the less affected by the hangover condition; complex II-III was markedly decreased by ethanol hangover showing 50% less activity than controls. Complex IV was 42% decreased as compared with control animals. Hydrogen peroxide production was 51% increased in brain cortex mitochondria from the hangover group, as compared with the control animals. Quantification of the mitochondrial transmembrane potential indicated that ethanol injected animals presented 17% less ability to maintain the polarized condition as compared with controls. These results indicate that a clear decrease in proton motive force occurs in brain cortex mitochondria during hangover conditions. We can conclude that a decreased motor performance observed in the hangover group of animals could be associated with brain cortex mitochondrial dysfunction and the resulting impairment of its energetic metabolism. PMID:22608205

  15. GPER1 (GPR30) knockout mice display reduced anxiety and altered stress response in a sex and paradigm dependent manner

    OpenAIRE

    Kastenberger, Iris; Schwarzer, Christoph

    2014-01-01

    The putative estrogen receptor GPER1 (the former orphan receptor GPR30) is discussed to be involved in emotional and cognitive functions and stress control. We recently described the induction of anxiety-like effects by the GPER1 agonist G-1 upon systemic injection into mice. To contribute to a better understanding of the role of GPER1 in anxiety and stress, we investigated germ-line GPER1 deficient mice. Our experiments revealed marked differences between the sexes. A mild but consistent phe...

  16. Inversion of left–right asymmetry alters performance of Xenopus tadpoles in nonlateralized cognitive tasks

    OpenAIRE

    Blackiston, Douglas J.; Levin, Michael

    2013-01-01

    Left–right behavioural biases are well documented across the animal kingdom, and handedness has long been associated with cognitive performance. However, the relationship between body laterality and cognitive ability is poorly understood. The embryonic pathways dictating normal left–right patterning have been molecularly dissected in model vertebrates, and numerous genetic and pharmacological treatments now facilitate experimental randomization or reversal of the left–right axis in these anim...

  17. Skeletal muscle alterations and exercise performance decrease in erythropoietin-deficient mice: a comparative study

    OpenAIRE

    Mille-Hamard Laurence; Billat Veronique L; Henry Elodie; Bonnamy Blandine; Joly Florence; Benech Philippe; Barrey Eric

    2012-01-01

    Abstract Background Erythropoietin (EPO) is known to improve exercise performance by increasing oxygen blood transport and thus inducing a higher maximum oxygen uptake (VO2max). Furthermore, treatment with (or overexpression of) EPO induces protective effects in several tissues, including the myocardium. However, it is not known whether EPO exerts this protective effect when present at physiological levels. Given that EPO receptors have been identified in skeletal muscle, we hypothesized that...

  18. Escalated handling of young C57BL/6 mice results in altered Morris water maze performance

    OpenAIRE

    Fridgeirsdottir, Gudrun Andrea; Hillered, Lars; Clausen, Fredrik

    2014-01-01

    Background The handling of experimental animals prior to experimental interventions is often poorly described, even though it may affect the final functional outcome. This study explores how the use of repeated handling of C57BL/6 mice prior to Morris water maze (MWM) tests can affect the performance. Methods and materials The handled animals were subjected to the escalating handling protocol, with the investigator spending 5 min per day per cage for 8 days prior to the MWM test. On the last ...

  19. Can Management Practices Make a Difference? Nonprofit Organization Financial Performance during Times of Economic Stress

    OpenAIRE

    Qian Hu; Naim Kapucu

    2015-01-01

    The economic crisis presented unprecedented challenges to nonprofit organizations to sustain their services. In this study, we examined both financial and management factors that influence the financial performance of nonprofit organizations during times of economic stress. In particular, we investigated whether strategic planning and plan implementation, revenue diversification, and board involvement help nonprofit organizations deal with financial uncertainty and strengthen financial perfor...

  20. Stress Sensitivity and Reading Performance in Spanish: A Study with Children

    Science.gov (United States)

    Gutierrez-Palma, Nicolas; Reyes, Alfonso Palma

    2007-01-01

    This paper investigates the relationship between ability to detect changes in prosody and reading performance in Spanish. Participants were children aged 7-8 years. Their tasks consisted of reading words, reading non-words, stressing non-words and reproducing sequences of two, three or four non-words by pressing the corresponding keys on the…

  1. Stress among Academic Staff and Students' Satisfaction of Their Performances in Payame Noor University of Miandoab

    Science.gov (United States)

    Jabari, Kamran; Moradi Sheykhjan, Tohid

    2015-01-01

    Present study examined the relationship between stress among academic staff and students' satisfaction of their performances in Payame Noor University (PNU) of Miandoab City, Iran in 2014. The methodology of the research is descriptive and correlation that descriptive and inferential statistics were used to analyze the data. Statistical Society…

  2. The Relationship between Stress, Job Performance, and Burnout in College Student Resident Assistants.

    Science.gov (United States)

    Nowak, Kenneth M.; Hanson, Alan L.

    1983-01-01

    Examined the relationship of stress, personality characteristics, and cognitive hardiness to job performance, burnout, and physical illness in resident assistants (N=37). Results indicated cognitive hardiness acts as a buffer against burnout and physical illness. Resident assistants rating themselves as Type A received poorer job performance…

  3. The decrease in histone methyltransferase EZH2 in response to fluid shear stress alters endothelial gene expression and promotes quiescence.

    NARCIS (Netherlands)

    Maleszewska, Monika; Vanchin, Byambasuren; Harmsen, Martin; Krenning, Guido

    2016-01-01

    High uniform fluid shear stress (FSS) is atheroprotective and preserves the endothelial phenotype and function through activation of downstream mediators such as MAPK7 (Erk5). Endothelial cells respond to FSS thanks to mechanotransduction. However, how the resulting signaling is integrated and resol

  4. Social Defeat Stress Produces Prolonged Alterations in Acoustic Startle and Body Weight Gain in Male Long Evans Rats

    OpenAIRE

    Pulliam, John V.K.; Dawaghreh, Ahmad M.; Alema-Mensah, Ernest; Plotsky, Paul M.

    2009-01-01

    Individuals exposed to psychological stressors may experience a long-term resetting of behavioral and neuroendocrine aspects of their “stress response” so that they either hyper or hypo-respond to subsequent stressors. These effects of psychological or traumatic stressors may be mimicked in rats using the resident-intruder model of social defeat.

  5. Alterations in stress granule dynamics driven by TDP-43 and FUS: A link to pathological inclusions in ALS?

    Directory of Open Access Journals (Sweden)

    Anais eAulas

    2015-10-01

    Full Text Available Stress granules (SGs are RNA-containing cytoplasmic foci formed in response to stress exposure. Since their discovery in 1999, over 120 proteins have been described to be localized to these structures (in 154 publications. Most of these components are RNA binding proteins (RBPs or are involved in RNA metabolism and translation. SGs have been linked to several pathologies including inflammatory diseases, cancer, viral infection and neurodegenerative diseases such as amyotrophic lateral sclerosis (ALS and frontotemporal dementia (FTD. In ALS and FTD, the majority of cases have no known etiology and exposure to external stress is frequently proposed as a contributor to either disease initiation or the rate of disease progression. Of note, both ALS and FTD are characterized by pathological inclusions, where some well-known SG markers localize with the ALS related proteins TDP-43 and FUS. We propose that TDP-43 and FUS serve as an interface between genetic susceptibility and environmental stress exposure in disease pathogenesis. Here, we will discuss the role of TDP-43 and FUS in SG dynamics and how disease-linked mutations affect this process.

  6. The Effect of Supplemental Grape Seed Extract on Pig Growth Performance and Body Composition During Heat Stress

    OpenAIRE

    Smithson, Andrew Todd

    2016-01-01

    Prolonged exposure to high ambient temperature without cooling causes heat stress (HS) resulting in altered growth, body composition and metabolic dysfunction in pigs. Grape seed extract (GSE) has been shown to reduce inflammation, and improve glucose transport and metabolism. Thus, GSE may be an effective supplement to combat the consequences of heat stress; however this possibility has not been evaluated in a large animal model. The objective of the current study was to examine the effect o...

  7. Plasmid-encoded tetracycline efflux pump protein alters bacterial stress responses and ecological fitness of Acinetobacter oleivorans.

    Directory of Open Access Journals (Sweden)

    Hyerim Hong

    Full Text Available Acquisition of the extracellular tetracycline (TC resistance plasmid pAST2 affected host gene expression and phenotype in the oil-degrading soil bacterium, Acinetobacter oleivorans DR1. Whole-transcriptome profiling of DR1 cells harboring pAST2 revealed that all the plasmid genes were highly expressed under TC conditions, and the expression levels of many host chromosomal genes were modulated by the presence of pAST2. The host energy burden imposed by replication of pAST2 led to (i lowered ATP concentrations, (ii downregulated expression of many genes involved in cellular growth, and (iii reduced growth rate. Interestingly, some phenotypes were restored by deleting the plasmid-encoded efflux pump gene tetH, suggesting that the membrane integrity changes resulting from the incorporation of efflux pump proteins also resulted in altered host response under the tested conditions. Alteration of membrane integrity by tetH deletion was shown by measuring permeability of fluorescent probe and membrane hydrophobicity. The presence of the plasmid conferred peroxide and superoxide resistance to cells, but only peroxide resistance was diminished by tetH gene deletion, suggesting that the plasmid-encoded membrane-bound efflux pump protein provided peroxide resistance. The downregulation of fimbriae-related genes presumably led to reduced swimming motility, but this phenotype was recovered by tetH gene deletion. Our data suggest that not only the plasmid replication burden, but also its encoded efflux pump protein altered host chromosomal gene expression and phenotype, which also alters the ecological fitness of the host in the environment.

  8. Repeated restraint stress alters sensitivity to the social consequences of ethanol differentially in early and late adolescent rats.

    OpenAIRE

    Varlinskaya, Elena I.; Truxell, Eric M.; Spear, Linda P.

    2013-01-01

    In rats, considerable differences in the social consequences of acute ethanol are seen across ontogeny, with adolescents being more sensitive to low dose ethanol-induced social facilitation and less sensitive to the social inhibition evident at higher ethanol doses relative to adults. Stressor exposure induces social anxiety-like behavior, indexed via decreases in social preference, and alters responsiveness to the social consequences of acute ethanol by enhancing ethanol-associated social fa...

  9. Perfluorooctanoic acid exposure alters polyunsaturated fatty acid composition, induces oxidative stress and activates the AKT/AMPK pathway in mouse epididymis.

    Science.gov (United States)

    Lu, Yin; Pan, Yitao; Sheng, Nan; Zhao, Allan Z; Dai, Jiayin

    2016-09-01

    Perfluorooctanoic acid (PFOA) is a degradation-resistant compound with a carbon-fluorine bond. Although PFOA emissions have been reduced since 2000, it remains persistent in the environment. Several studies on laboratory animals indicate that PFOA exposure can impact male fertility. Here, adult male mice received either PFOA (1.25, 5 or 20 mg/kg/d) or an equal volume of water for 28 d consecutively. PFOA accumulated in the epididymis in a dose-dependent manner and resulted in reduced epididymis weight, lower levels of triglycerides (TG), cholesterol (CHO), and free fatty acids (FFA), and activated AKT/AMPK signaling in the epididymis. Altered polyunsaturated fatty acid (PUFA) compositions, such as a higher arachidonic acid:linoleic acid (AA:LA) ratio, concomitant with excessive oxidative stress, as demonstrated by increased malonaldehyde (MDA) and decreased glutathione peroxidase (GSH-Px) in the epididymis, were observed in epididymis tissue following treatment with PFOA. These results indicate that the epididymis is a potential target of PFOA. Oxidative stress and PUFA alteration might help explain the sperm injury and male reproductive dysfunction induced by PFOA exposure. PMID:27262104

  10. A case study to determine stress sources affecting the academic performance

    Directory of Open Access Journals (Sweden)

    Aytaç Aydın

    2011-07-01

    Full Text Available Job stress affects academicians in terms of performance, scientific production, job satisfaction and health. This effect may differ according to the academicians in the structure of the organization. It is possible to mention about positive stress if organization structure positively affects academician, but it is called negative stress if it negatively affects. Lack of fee and powers, injustice employee evaluation, not getting in return for work are important stress sources. In this study, some of the factors that affect stress levels (individual, organizational and physical environmental factors of academicians (professors, associate professors and assistant professors who work in Karadeniz Technical University are investigated by questionnaire method. The survey data is evaluated with Structural Equation Model (SEM which is prepared in statistical package programs SPSS 16.0 and AMOS 16.0 and the results are revealed. As a result, factors effecting academic members' stress levels are determined as individual and organizational factors (p<0,1. Thus, it is concluded that physical environmental factors such as noise, lightening and crowded place do not cause tension on academician

  11. Stress Response and the Adolescent Transition: Performance versus Peer Rejection Stressors

    OpenAIRE

    Stroud, Laura R.; Foster, Elizabeth; Papandonatos, George D.; Handwerger, Kathryn; Granger, Douglas A.; KIVLIGHAN, Katie T.; Niaura, Raymond

    2009-01-01

    Little is known about normative variation in stress response over the adolescent transition. This study examined neuroendocrine and cardiovascular responses to performance and peer rejection stressors over the adolescent transition in a normative sample. Participants were 82 healthy children (ages 7-12 years, n=39, 22 females) and adolescents (ages 13-17, n=43, 20 females) recruited through community postings. Following a habituation session, participants completed a performance (public speak...

  12. The effect of performance-based pay systems on job satisfaction and stress

    OpenAIRE

    Hornbach, Jessica Janina

    2013-01-01

    Previous investigations regarding the health- and wellbeing-related outcomes of performance-based pay systems have been scarce and ambiguous so far. Considering the huge economic and organizational impact of stress-related health problems, it is important to further investigate this relation, including the impact of different variables that can help to explain the variation in the relationship between performance-based pay and job strain. The main purpose of this study is to challenge the res...

  13. Complexity of physiological responses decreases in high-stress musical performance

    OpenAIRE

    Williamon, Aaron; Aufegger, Lisa; Wasley, David; Looney, David; Mandic, Danilo P.

    2013-01-01

    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-in...

  14. MONITORING TRAINING LOADS, STRESS, IMMUNE-ENDOCRINE RESPONSES AND PERFORMANCE IN TENNIS PLAYERS

    Science.gov (United States)

    Moreira, A.; Lodo, L.; Nosaka, K.; Coutts, A.J.; Aoki, M.S.

    2013-01-01

    The study aim was to investigate the effect of a periodised pre-season training plan on internal training load and subsequent stress tolerance, immune-endocrine responses and physical performance in tennis players. Well-trained young tennis players (n = 10) were monitored across the pre-season period, which was divided into 4 weeks of progressive overloading training and a 1-week tapering period. Weekly measures of internal training load, training monotony and stress tolerance (sources and symptoms of stress) were taken, along with salivary testosterone, cortisol and immunoglobulin A. One repetition maximum strength, running endurance, jump height and agility were assessed before and after training. The periodised training plan led to significant weekly changes in training loads (i.e. increasing in weeks 3 and 4, decreasing in week 5) and post-training improvements in strength, endurance and agility (P < 0.05). Cortisol concentration and the symptoms of stress also increased in weeks 3 and/or 4, before returning to baseline in week 5 (P < 0.05). Conversely, the testosterone to cortisol ratio decreased in weeks 3 and 4, before returning to baseline in week 5 (P < 0.05). In conclusion, the training plan evoked adaptive changes in stress tolerance and hormonal responses, which may have mediated the improvements in physical performance. PMID:24744485

  15. EFFECT OF MEAN STRESS ON FATIGUE PERFORMANCE OF WELDED JOINTS TREATED BY UPT

    Institute of Scientific and Technical Information of China (English)

    Wang Dongpo; Huo Lixing; Wang Ting; Li Jie; Zhang Yufeng

    2004-01-01

    The fatigue contrast tests of unload longitudinal direction corner joints as original welded and treated by ultrasonic peening of Q235B in various stress ratio are directed. The improvements of fatigue performance of unload longitudinal direction corner joints resulted by ultrasonic peening are studied. The effect pattern of stress ratio on fatigue performance of welded joints that are treated by ultrasonic peening is studied. As tests results indicate that: ① In the condition of stress ratio R= -1, the fatigue strength of specimen treated by ultrasonic peening is increased by 165% of that of the original welded specimen. And the fatigue life of specimen treated by ultrasonic peening is as much as 75~210 times of that of the latter. When R=0.1, the fatigue strength is increased by 87% and the fatigue life is extended by 21~29 times. When R= -0.5, the fatigue strength is increased by 123% and the fatigue life is extended by 42~59 times. When R=0.45, the fatigue strength is increased by 51% and the fatigue life is extended by 3~14 times. ② If the welded joints are treated by ultrasonic peening, the fatigue strength is no longer independent on the applied mean stress. The more the stress ratio R, the less the fatigue stress range which can be sustained by the joints is. ③ Whether the high value residual stress is in the joints or not, the dead load portion of the applied load must be considered in the design of the joints which should be treated by ultrasonic peening.

  16. The effects of cognitive and behavioral control on post-stress performance

    Science.gov (United States)

    Foushee, H. C.; Davis, M. H.; Stephan, W. G.; Bernstein, W. M.

    1980-01-01

    A study was designed to investigate the effects of behavioral and cognitive control on post-stress performance. Half of the subjects exposed to loud unpredictable noise bursts were given 'behavioral' control (a button which would terminate the noise), while the other half had no behavioral control. In addition, subjects were provided with one of three levels of feedback (success, failure, or no feedback) regarding their performance during the noise. It was expected that information about performance would provide subjects with an increased sense of 'cognitive' control which would affect their appraisal of stressful events and their later performance. The results indicated that subjects given feedback performed better on subsequent tasks than those given no feedback. Perceived behavioral control had little effect on performance. The causal attributions made by subjects were used to interpret these effects. These findings were viewed as supportive of Averill's (1973) notion that various types of control are related to stress in a complex fashion. The data may also support the reformulation by Abramson et al. (1978) of learned helplessness theory.

  17. Do plant viruses facilitate their aphid vectors by inducing symptoms that alter behavior and performance?

    Science.gov (United States)

    Hodge, Simon; Powell, Glen

    2008-12-01

    Aphids can respond both positively and negatively to virus-induced modifications of the shared host plant. It can be speculated that viruses dependent on aphids for their transmission might evolve to induce changes in the host plant that attract aphids and improve their performance, subsequently enhancing the success of the pathogen itself. We studied how pea aphids [Acyrthosiphon pisum (Harris)] responded to infection of tic beans (Vicia faba L.) by three viruses with varying degrees of dependence on this aphid for their transmission: pea enation mosaic virus (PEMV), bean yellow mosaic virus (BYMV), and broad bean mottle virus (BBMV). BYMV has a nonpersistent mode of transmission by aphids, whereas PEMV is transmitted in a circulative-persistent manner. BBMV is not aphid transmitted. When reared on plants infected by PEMV, no changes in aphid survival, growth, or reproductive performance were observed, whereas infection of beans by the other aphid-dependent virus, BYMV, actually caused a reduction in aphid survival in some assays. None of the viruses induced A. pisum to increase production of winged progeny, and aphids settled preferentially on leaf tissue from plants infected by all three viruses, the likely mechanism being visual responses to yellowing of foliage. Thus, in this system, the attractiveness of an infected host plant and its quality in terms of aphid growth and reproduction were not related to the pathogen's dependence on the aphid for transmission to new hosts. PMID:19161702

  18. Altered gene expression and spine density in nucleus accumbens of adolescent and adult male mice exposed to emotional and physical stress.

    Science.gov (United States)

    Warren, Brandon L; Sial, Omar K; Alcantara, Lyonna F; Greenwood, Maria A; Brewer, Jacob S; Rozofsky, John P; Parise, Eric M; Bolaños-Guzmán, Carlos A

    2014-01-01

    Stressful early life experiences are implicated in lifelong health. However, little is known about the consequences of emotional stress (ES) or physical stress (PS) on neurobiology. Therefore, the following set of experiments was designed to assess changes in transcription and translation of key proteins within the nucleus accumbens (NAc). Male adolescent (postnatal day 35) or adult (8-week-old) mice were exposed to ES or PS using a witness social defeat paradigm. Then, 24 h after the last stress session, we measured levels of specific mRNAs and proteins within the NAc. Spine density was also assessed in separate groups of mice. Exposure to ES or PS disrupted extracellular signal-related kinase 2 (ERK2), reduced transcription of ΔFosB and had no effect on cAMP response element-binding protein (CREB) mRNA. Western blots revealed that exposure to ES or PS decreased ERK2 phosphorylation in adolescents, whereas the same stress regimen increased ERK2 phosphorylation in adults. Exposure to ES or PS had no effect on ΔFosB or CREB phosphorylation. ES and PS increased spine density in the NAc of adolescent exposed mice, but only exposure to PS increased spine density in adults. Together, these findings demonstrate that exposure to ES or PS is a potent stressor in adolescent and adult mice and can disturb the integrity of the NAc by altering transcription and translation of important signaling molecules in an age-dependent manner. Furthermore, exposure to ES and PS induces substantial synaptic plasticity of the NAc. PMID:24943326

  19. Social play in juvenile hamsters alters dendritic morphology in the medial prefrontal cortex and attenuates effects of social stress in adulthood.

    Science.gov (United States)

    Burleson, Cody A; Pedersen, Robert W; Seddighi, Sahba; DeBusk, Lauren E; Burghardt, Gordon M; Cooper, Matthew A

    2016-08-01

    Social play is a fundamental aspect of behavioral development in many species. Social play deprivation in rats alters dendritic morphology in the ventromedial prefrontal cortex (vmPFC) and we have shown that this brain region regulates responses to social defeat stress in Syrian hamsters. In this study, we tested whether play deprivation during the juvenile period disrupts dendritic morphology in the prefrontal cortex and potentiates the effects of social defeat stress. At weaning, male hamsters were either group-housed with peers or pair-housed with their mother, with whom they do not play. In adulthood, animals received acute social defeat stress or no-defeat control treatment. The hamsters were then tested for a conditioned defeat response in a social interaction test with a novel intruder, and were also tested for social avoidance of a familiar opponent. Brains were collected for Golgi-Cox staining and analysis of dendritic morphology in the infralimbic (IL), prelimbic (PL), and orbitofrontal cortex (OFC). Play-deprived animals showed an increased conditioned defeat response and elevated avoidance of a familiar opponent compared with play-exposed animals. Furthermore, play-deprived animals showed increased total length and branch points in apical dendrites of pyramidal neurons in the IL and PL cortices, but not in the OFC. These findings suggest that social play deprivation in juvenile hamsters disrupts neuronal development in the vmPFC and increases vulnerability to the effects of social stress in adulthood. Overall, these results suggest that social play is necessary for the natural dendritic pruning process during adolescence and promotes coping with stress in adulthood. (PsycINFO Database Record PMID:27176563

  20. Motion and emotion: depression reduces psychomotor performance and alters affective movements in caregiving interactions

    Directory of Open Access Journals (Sweden)

    Katherine S Young

    2015-02-01

    Full Text Available Background: Impaired social functioning is a well-established feature of depression. Evidence to date suggests that disrupted processing of emotional cues may constitute part of this impairment. Beyond processing of emotional cues, fluent social interactions require that people physically move in synchronised, contingent ways. Disruptions to physical movements are a diagnostic feature of depression (psychomotor disturbance but have not previously been assessed in the context of social functioning. Here we investigated the impact of psychomotor disturbance in depression on physical responsive behaviour in both an experimental and observational setting.Methods: In Experiment 1, we examined motor disturbance in depression in response to salient emotional sounds, using a laboratory-based effortful motor task. In Experiment 2, we explored whether psychomotor disturbance was apparent in real-life social interactions. Using mother-infant interactions as a model affective social situation, we compared physical behaviours of mothers with and without postnatal depression (PND.Results: We found impairments in precise, controlled psychomotor performance in adults with depression relative to healthy adults (Experiment 1. Despite this disruption, all adults showed enhanced performance following exposure to highly salient emotional cues (infant cries. Examining real-life interactions, we found differences in physical movements, namely reduced affective touching, in mothers with PND responding to their infants, compared to healthy mothers (Experiment 2.Conclusions: Together, these findings suggest that psychomotor disturbance may be an important feature of depression that can impair social functioning. Future work investigating whether improvements in physical movement in depression could have a positive impact on social interactions would be of much interest.

  1. Job Stress, Stress Related to Performance-Based Accreditation, Locus of Control, Age, and Gender As Related to Job Satisfaction and Burnout in Teachers and Principals.

    Science.gov (United States)

    Hipps, Elizabeth Smith; Halpin, Glennelle

    The purpose of the study described here was to: (1) determine the amount of variance in burnout and job satisfaction in public school teachers and principals which could be accounted for by stress related to the state's performance-based accreditation standards; (2) examine the relationship between stress related to state standards and the age and…

  2. Impact of Stress on Employee’s Performance: A Study on Teachers of Private Colleges of Rawalpindi

    Directory of Open Access Journals (Sweden)

    Syed Saad Hussain Shah

    2012-04-01

    Full Text Available The purpose of this research is to investigate the stress issues associated with the college teachers and the effect of stress on their performance in scope of organizational performance. The results show that the stress is affected by the reward system that significantly and positively affects the efficiency of employee similarly organizational structure clearly has valuable effects on the efficiency of employee too. Stress is vital part to examine in case of employees and organizational structure where rewards has great influence on the stress factor of employee.

  3. Improvement of mood and sleep alterations in posttraumatic stress disorder patients by eye movement desensitization and reprocessing

    OpenAIRE

    Fabiana Fernanda Dias Alonso; Sergio Tufik; Deborah Suchecki

    2014-01-01

    Posttraumatic stress disorder (PTSD) patients exhibit depressive and anxiety symptoms, in addition to nightmares, which interfere with sleep continuity. Pharmacologic treatment of these sleep problems improves PTSD symptoms, but very few studies have used psychotherapeutic interventions to treat PTSD and examined their effects on sleep quality. Therefore, in the present study, we sought to investigate the effects of Eye Movement Desensitization Reprocessing therapy on indices of mood, anxiety...

  4. Altered Memory Capacities and Response to Stress in p300/CBP-Associated Factor (PCAF) Histone Acetylase Knockout Mice

    OpenAIRE

    Maurice, Tangui; Duclot, Florian; Meunier, Johann; Naert, Gaëlle; Givalois, Laurent; Meffre, Julie; Célérier, Aurélie; Jacquet, Chantal; Copois, Virginie; Mechti, Nadir; Ozato, Keiko; Gongora, Céline

    2007-01-01

    International audience Chromatin remodeling by posttranslational modification of histones plays an important role in brain plasticity, including memory, response to stress and depression. The importance of H3/4 histones acetylation by CREB-binding protein (CBP) or related histone acetyltransferase, including p300, was specifically demonstrated using knockout (KO) mouse models. The physiological role of a related protein that also acts as a transcriptional coactivator with intrinsic histone...

  5. Exercise‐induced alterations in pancreatic oxidative stress and mitochondrial function in type 2 diabetic Goto‐Kakizaki rats

    OpenAIRE

    Raza, Haider; John, Annie; Shafarin, Jasmin; Howarth, Frank C.

    2016-01-01

    Abstract Progressive metabolic complications accompanied by oxidative stress are the hallmarks of type 2 diabetes. The precise molecular mechanisms of the disease complications, however, remain elusive. Exercise‐induced nontherapeutic management of type 2 diabetes is the first line of choice to control hyperglycemia and diabetes associated complications. In this study, using 11‐month‐old type 2 Goto‐Kakizaki (GK) rats, we have investigated the effects of exercise on mitochondrial metabolic an...

  6. Gray Matter Alterations in Post-Traumatic Stress Disorder, Obsessive–Compulsive Disorder, and Social Anxiety Disorder

    OpenAIRE

    Cheng, Bochao; Huang, Xiaoqi; Li, Shiguang; Hu, Xinyu; Luo, Ya; Wang, Xiuli; Yang, Xun; Qiu, Changjian; Yang, Yanchun; Zhang, Wei; Bi, Feng; Roberts, Neil; Gong, Qiyong

    2015-01-01

    Post-traumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), and social anxiety disorder (SAD) all bear the core symptom of anxiety and are separately classified in the new DSM-5 system. The aim of the present study is to obtain evidence for neuroanatomical difference for these disorders. We applied voxel-based morphometry (VBM) with Diffeomorphic Anatomical Registration Through Exponentiated Lie to compare gray matter volume (GMV) in magnetic resonance images obtained for 30 p...

  7. Hypothyroidism minimizes the effects of acute hepatic failure caused by endoplasmic reticulum stress and redox environment alterations in rats.

    Science.gov (United States)

    Blas-Valdivia, Vanessa; Cano-Europa, Edgar; Martinez-Perez, Yoalli; Lezama-Palacios, Ruth; Franco-Colin, Margarita; Ortiz-Butron, Rocio

    2015-10-01

    The aim of this study was to investigate if a protective effect from hypothyroidism in acute liver failure resulted from reduced endoplasmic reticulum stress and changes to the redox environment. Twenty male Sprague-Dawley rats were divided in four groups: (1) euthyroid (sham surgery), (2) hypothyroid, (3) euthyroid (sham surgery)+thioacetamide and (4) hypothyroid+thioacetamide. Hypothyroidism was confirmed two weeks after thyroidectomy, and thioacetamide (TAA) (400mg/kg, ip) was administrated to the appropriate groups for three days with supportive therapy. Grades of encephalopathy in all animals were determined using behavioral tests. Animals were decapitated and their blood was obtained to assess liver function. The liver was dissected: the left lobe was used for histology and the right lobe was frozen for biochemical assays. Body weight, rectal temperature and T4 concentration were lower in hypothyroid groups. When measurements of oxidative stress markers, redox environment, γ-glutamylcysteine synthetase and glutathione-S-transferase were determined, we observed that hypothyroid animals with TAA compensated better with oxidative damage than euthyroid animals treated with TAA. Furthermore, we measured reduced expressions of GADD34, caspase-12 and GRP78 and subsequently less hypothyroidism-induced cellular damage in hypothyroid animals. We conclude that hypothyroidism protects against hepatic damage caused by TAA because it reduces endoplasmic reticulum stress and changes to the redox environment. PMID:26238033

  8. Long-term in vivo polychlorinated biphenyl 126 exposure induces oxidative stress and alters proteomic profile on islets of Langerhans

    OpenAIRE

    Loiola, Rodrigo Azevedo; dos Anjos, Fabyana Maria; Shimada, Ana Lúcia; Cruz, Wesley Soares; Drewes, Carine Cristiane; Rodrigues, Stephen Fernandes; Cardozo, Karina Helena Morais; Carvalho, Valdemir Melechco; Pinto, Ernani; Farsky, Sandra Helena

    2016-01-01

    It has been recently proposed that exposure to polychlorinated biphenyls (PCBs) is a risk factor to type 2 diabetes mellitus (DM2). We investigated this hypothesis using long-term in vivo PCB126 exposure to rats addressing metabolic, cellular and proteomic parameters. Male Wistar rats were exposed to PCB126 (0.1, 1 or 10 μg/kg of body weight/day; for 15 days) or vehicle by intranasal instillation. Systemic alterations were quantified by body weight, insulin and glucose tolerance, and blood bi...

  9. Can we understand how developmental stress enhances performance under future threat with the Yerkes-Dodson law?

    OpenAIRE

    Chaby, Lauren E; Michael J Sheriff; Hirrlinger, Amy M.; Braithwaite, Victoria A.

    2015-01-01

    Recently we have shown that adult rats exposed to chronic stress during adolescence increase foraging performance in high-threat conditions by 43% compared to rats reared without stress. Our findings suggest that stress during adolescence can prepare rats to better function under future threat, which supports hypotheses describing an adaptive role for the long-term consequences of early stress (e.g. the thrifty phenotype and maternal mismatch hypotheses). These hypotheses often predict that e...

  10. Effect of aging on performance, muscle activation and perceived stress during mentally demanding computer tasks

    DEFF Research Database (Denmark)

    Alkjaer, Tine; Pilegaard, Marianne; Bakke, Merete;

    2005-01-01

    OBJECTIVES: This study examined the effects of age on performance, muscle activation, and perceived stress during computer tasks with different levels of mental demand. METHODS: Fifteen young and thirteen elderly women performed two computer tasks [color word test and reference task] with different...... levels of mental demand but similar physical demands. The performance (clicking frequency, percentage of correct answers, and response time for correct answers) and electromyography from the forearm, shoulder, and neck muscles were recorded. Visual analogue scales were used to measure the participants....... Likewise, a higher level of self-reported stress was found for the elderly participants after the color word test. During the reference task higher electromyographic levels and reported difficulty were recorded for the elderly group than for the young group. CONCLUSIONS: The findings suggest that mental...

  11. Effects of acceptance-based coping on task performance and subjective stress.

    Science.gov (United States)

    Kishita, Naoko; Shimada, Hironori

    2011-03-01

    This paper examines the interactive effects of acceptance-based coping and job control on task performance, subjective stress, and perceived control. Forty-eight undergraduate and graduate students first participated in brief educational programs based on either acceptance or control coping strategies. They then participated in a 30-min high workload task under either high or low job control conditions. The results demonstrated a significant interactive effect of acceptance-based coping and job control on perceived control and task performance. No such effect was found for subjective stress. We conclude that to improve employees' perceived control and job performance, there should be an increase not only in job control through work redesign, but also in psychological acceptance. PMID:21074000

  12. Iron dextran increases hepatic oxidative stress and alters expression of genes related to lipid metabolism contributing to hyperlipidaemia in murine model.

    Science.gov (United States)

    Silva, Maísa; da Costa Guerra, Joyce Ferreira; Sampaio, Ana Flávia Santos; de Lima, Wanderson Geraldo; Silva, Marcelo Eustáquio; Pedrosa, Maria Lucia

    2015-01-01

    The objective of this study was to investigate the effects of iron dextran on lipid metabolism and to determine the involvement of oxidative stress. Fischer rats were divided into two groups: the standard group (S), which was fed the AIN-93M diet, and the standard plus iron group (SI), which was fed the same diet but also received iron dextran injections. Serum cholesterol and triacylglycerol levels were higher in the SI group than in the S group. Iron dextran was associated with decreased mRNA levels of pparα, and its downstream gene cpt1a, which is involved in lipid oxidation. Iron dextran also increased mRNA levels of apoB-100, MTP, and L-FABP indicating alterations in lipid secretion. Carbonyl protein and TBARS were consistently higher in the liver of the iron-treated rats. Moreover, a significant positive correlation was found between oxidative stress products, lfabp expression, and iron stores. In addition, a negative correlation was found between pparα expression, TBARS, carbonyl protein, and iron stores. In conclusion, our results suggest that the increase observed in the transport of lipids in the bloodstream and the decreased fatty acid oxidation in rats, which was promoted by iron dextran, might be attributed to increased oxidative stress. PMID:25685776

  13. Iron Dextran Increases Hepatic Oxidative Stress and Alters Expression of Genes Related to Lipid Metabolism Contributing to Hyperlipidaemia in Murine Model

    Directory of Open Access Journals (Sweden)

    Maísa Silva

    2015-01-01

    Full Text Available The objective of this study was to investigate the effects of iron dextran on lipid metabolism and to determine the involvement of oxidative stress. Fischer rats were divided into two groups: the standard group (S, which was fed the AIN-93M diet, and the standard plus iron group (SI, which was fed the same diet but also received iron dextran injections. Serum cholesterol and triacylglycerol levels were higher in the SI group than in the S group. Iron dextran was associated with decreased mRNA levels of pparα, and its downstream gene cpt1a, which is involved in lipid oxidation. Iron dextran also increased mRNA levels of apoB-100, MTP, and L-FABP indicating alterations in lipid secretion. Carbonyl protein and TBARS were consistently higher in the liver of the iron-treated rats. Moreover, a significant positive correlation was found between oxidative stress products, lfabp expression, and iron stores. In addition, a negative correlation was found between pparα expression, TBARS, carbonyl protein, and iron stores. In conclusion, our results suggest that the increase observed in the transport of lipids in the bloodstream and the decreased fatty acid oxidation in rats, which was promoted by iron dextran, might be attributed to increased oxidative stress.

  14. Effect of heat stress on reproductive performances of dairy cattle and buffaloes: A review

    Directory of Open Access Journals (Sweden)

    Soumya Dash

    2016-03-01

    Full Text Available Heat stress has adverse effects on the reproductive performances of dairy cattle and buffaloes. The dairy sector is a more vulnerable to global warming and climate change. The temperature humidity index (THI is the widely used index to measure the magnitude of heat stress in animals. The bjective of this paper was to assess the decline in performances of reproductive traits such as service period, conception rate and pregnancy rate of dairy cattle and buffaloes with respect to increase in THI. The review stated that service period in cattle is affected by season of calving for which cows calved in summer had the longest service period. The conception rate and pregnancy rate in dairy cattle were found decreased above THI 72 while a significant decline in reproductive performances of buffaloes was observed above threshold THI 75. The non-heat stress zone (HSZ (October to March is favorable for optimum reproductive performance, while fertility is depressed in HSZ (April to September and critical HSZ (CHSZ (May and June. Heat stress in animals has been associated with reduced fertility through its deleterious impact on oocyte maturation and early embryo development. The management strategies viz., nutrition modification, environment modification and timed artificial insemination protocol are to be strictly operated to ameliorate the adverse effects of heat stress in cattle and buffaloes during CHSZ to improve their fertility. The identification of genes associated with heat tolerance, its incorporation into breeding program and the inclusion of THI covariate effects in selection index should be targeted for genetic evaluation of dairy animals in the hot climate.

  15. Effect of heat stress on reproductive performances of dairy cattle and buffaloes: A review.

    Science.gov (United States)

    Dash, Soumya; Chakravarty, A K; Singh, Avtar; Upadhyay, Arpan; Singh, Manvendra; Yousuf, Saleem

    2016-03-01

    Heat stress has adverse effects on the reproductive performances of dairy cattle and buffaloes. The dairy sector is a more vulnerable to global warming and climate change. The temperature humidity index (THI) is the widely used index to measure the magnitude of heat stress in animals. The objective of this paper was to assess the decline in performances of reproductive traits such as service period, conception rate and pregnancy rate of dairy cattle and buffaloes with respect to increase in THI. The review stated that service period in cattle is affected by season of calving for which cows calved in summer had the longest service period. The conception rate and pregnancy rate in dairy cattle were found decreased above THI 72 while a significant decline in reproductive performances of buffaloes was observed above threshold THI 75. The non-heat stress zone (HSZ) (October to March) is favorable for optimum reproductive performance, while fertility is depressed in HSZ (April to September) and critical HSZ (CHSZ) (May and June). Heat stress in animals has been associated with reduced fertility through its deleterious impact on oocyte maturation and early embryo development. The management strategies viz., nutrition modification, environment modification and timed artificial insemination protocol are to be strictly operated to ameliorate the adverse effects of heat stress in cattle and buffaloes during CHSZ to improve their fertility. The identification of genes associated with heat tolerance, its incorporation into breeding program and the inclusion of THI covariate effects in selection index should be targeted for genetic evaluation of dairy animals in the hot climate. PMID:27057105

  16. Characterization of oncogene-induced metabolic alterations in hepatic cells by using ultrahigh performance liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Tang, Zhi; Cao, Tingting; Lin, Shuhai; Fu, Li; Li, Shangfu; Guan, Xin-Yuan; Cai, Zongwei

    2016-05-15

    Elucidation of altered metabolic pathways by using metabolomics may open new avenues for basic research on disease mechanisms and facilitate the development of novel therapeutic strategies. Here, we report the development of ultrahigh performance liquid chromatography-tandem mass spectrometry-based metabolomics platform with capability of measuring both cationic and anionic intermediates in cellular metabolism. The platform was established based on the hydrophobic ion-pairing interaction chromatography coupled with tandem mass spectrometry in multiple reaction monitoring (MRM) mode. The MRM transitions were created and optimized via energy-resolved collision-induced dissociation experiments, serving as an essential reference point for the quantification and identification. For chromatographic separation, application of hydrophobic ion-pairing interaction led to dramatic enhancement on retention of water-soluble metabolites and provision of good peak shapes. Two volatile ion-pairing reagents, namely heptafluorobutyric acid and tributylamine, were used with dedicated C18 columns as complementary separation systems coupled with the MRM analysis, allowing measurement of the metabolites of interest at nanomolar levels. The developed platform was successfully applied to investigate the altered metabolism in hepatic cells with over-expression of an oncogene, thus can provide important information on the rewired metabolism. PMID:26992502

  17. Alterations in DRH and DRL performance in rats developmentally exposed to an environmental PCB mixture.

    Science.gov (United States)

    Sable, Helen J K; Powers, Brian E; Wang, Victor C; Widholm, John J; Schantz, Susan L

    2006-01-01

    Schedule-controlled responding was examined in offspring of rats exposed to a PCB mixture formulated to mimic the PCB congener profile in fish from the Fox River in Green Bay, WI. Female rats were administered 0, 1, 3, or 6 mg/kg/day of the PCB mixture beginning four weeks prior to breeding until weaning on postnatal day 21. When offspring were approximately 235 days old, they were tested on three different schedules of a differential reinforcement of high rate (DRH) operant task (DRH 2:1, DRH 4:2, and DRH 8:4). DRH testing was followed by testing on the differential reinforcement of low rate (DRL) operant task in which rats had to inhibit responding until 15 s had elapsed (DRL 15) from the previous response in order to obtain a food reinforcer. After completion of DRL 15 testing, 3 days of extinction testing were conducted (DRL EXT) during which no reinforcers were delivered. Developmental exposure to the higher PCB doses resulted in shorter inter-response times (IRTs) and shorter response durations during DRH 8:4, which translated into a greater percentage of reinforced trials. For DRL 15, no significant exposure-related effects were observed on the number of responses or reinforcers earned, or the number or proportion of responses with long or short inter-response times during acquisition or steady state performance. However, during DRL EXT, rats developmentally exposed to the highest PCB dose responded more than controls, produced significantly more short IRT responses, and had a significantly lower proportion of long IRT responses. Overall, exposure to this PCB mixture resulted in increased responding which was suggestive of a deficit in inhibitory control. PMID:16930942

  18. Development of a standardized battery of performance tests for the assessment of noise stress effects

    Science.gov (United States)

    Theologus, G. C.; Wheaton, G. R.; Mirabella, A.; Brahlek, R. E.

    1973-01-01

    A set of 36 relatively independent categories of human performance were identified. These categories encompass human performance in the cognitive, perceptual, and psychomotor areas, and include diagnostic measures and sensitive performance metrics. Then a prototype standardized test battery was constructed, and research was conducted to obtain information on the sensitivity of the tests to stress, the sensitivity of selected categories of performance degradation, the time course of stress effects on each of the selected tests, and the learning curves associated with each test. A research project utilizing a three factor partially repeated analysis of covariance design was conducted in which 60 male subjects were exposed to variations in noise level and quality during performance testing. Effects of randomly intermittent noise on performance of the reaction time tests were observed, but most of the other performance tests showed consistent stability. The results of 14 analyses of covariance of the data taken from the performance of the 60 subjects on the prototype standardized test battery provided information which will enable the final development and test of a standardized test battery and the associated development of differential sensitivity metrics and diagnostic classificatory system.

  19. Effect of residual stresses and metallographic stability on the over all performance of integral diaphragm material

    International Nuclear Information System (INIS)

    The integral diaphragm pressure transducer consists of a diaphragm machined from precipitation hardened martensitic (APX4) steel. Its performance is quite significant as it depends upon various factors such as mechanical properties including induced residual stress levels, metallurgical and physical parameters due to different stages of processing involved. Hence, the measurement and analysis of residual stress becomes very important from the point of in-service assessment of a component. In the present work, the stress measurements have been done using the X-ray diffraction (XRD) technique, which is a non-destructive test (NDT). This method is more reliable and widely used compared to the other NDT techniques. The metallurgical aspects have been studied by adopting the conventional metallographic practices including examination of microstructure using light microscope. The dimensional measurements have been carried out using dimensional gauge. The results of the present investigation reveals that the diaphragm material after undergoing series of realization processes has yielded good amount of retained austenite in it. Also, the presence of higher compressive stresses induced in the transducer results in non-linearity, zero shift and dimensional instability. The problem of higher retained austenite content and higher compressive stress have been overcome by adopting a new realization process involving machining and cold and hot stabilization soak which has brought down the retained austenite content to about 5-6% and acceptable level of compressive stress in the range -100 to -150 MPa with fine tempered martensitic phase structure and good dimensional stability. The new realization process seems to be quite effective in terms of controlling retained austenite content, residual stress, metallurgical phase as well as dimensional stability and this may result in minimum zero shift of the diaphragm system.

  20. Can Management Practices Make a Difference? Nonprofit Organization Financial Performance during Times of Economic Stress

    Directory of Open Access Journals (Sweden)

    Qian Hu

    2016-02-01

    Full Text Available The economic crisis presented unprecedented challenges to nonprofit organizations to sustain their services. In this study, we examined both financial and management factors that influence the financial performance of nonprofit organizations during times of economic stress. In particular, we investigated whether strategic planning and plan implementation, revenue diversification, and board involvement help nonprofit organizations deal with financial uncertainty and strengthen financial performance. Despite the negative impacts that the economic downturn had on nonprofit organizations, we found that the implementation of strategic plans can help nonprofit organizations reduce financial vulnerability. Our findings call attention to key management factors that influence the financial performance of nonprofit organizations.

  1. Can Management Practices Make a Difference? Nonprofit Organization Financial Performance during Times of Economic Stress

    Directory of Open Access Journals (Sweden)

    Qian HU

    2015-05-01

    Full Text Available The economic crisis presented unprecedented challenges to nonprofit organizations to sustain their services. In this study, we examined both financial and management factors that influence the financial performance of nonprofit organizations during times of economic stress. In particular, we investigated whether strategic planning and plan implementation, revenue diversification, and board involvement help nonprofit organizations deal with financial uncertainty and strengthen financial performance. Despite the negative impacts that the economic downturn had on nonprofit organizations, we found that the implementation of strategic plans can help nonprofit organizations reduce financial vulnerability. Our findings call attention to key management factors that influence the financial performance of nonprofit organizations.

  2. Time and motion, experiment M151. [human performance and space flight stress

    Science.gov (United States)

    Kubis, J. F.; Elrod, J. T.; Rusnak, R.; Mcbride, G. H.; Barnes, J. E.; Saxon, S. C.

    1973-01-01

    Astronaut work performance during the preparation and execution of experiments in simulated Skylab tests was analyzed according to time and motion in order to evaluate the efficiency and consistency of performance (adaptation function) for several different types of activity over the course of the mission; to evaluate the procedures to be used by the same experiment in Skylab; to generate characteristic adaptation functions for later comparison with Skylab data; and to examine astronaut performance for any behavioral stress due to the environment. The overall results indicate that the anticipated adaptation function was obtained both for individual and for averaged data.

  3. Stress and Academic Performance in Dental Students: The Role of Coping Strategies and Examination-Related Self-Efficacy.

    Science.gov (United States)

    Crego, Antonio; Carrillo-Diaz, María; Armfield, Jason M; Romero, Martín

    2016-02-01

    Academic stress negatively affects students' performance. However, little is known of the processes that may be involved in this association. This study aimed to analyze how other variables such as coping strategies and exam-related self-efficacy could be related to academic stress and performance for dental students. An online survey, including measures of coping strategies, perceived stress, exam-related self-efficacy, and academic performance, was completed by undergraduate dental students in Madrid, Spain. Of the 275 students invited to take the survey, 201 participated (response rate 73.6%). Rational coping strategies (problem-solving, positive reappraisal, seeking social support) were negatively associated with perceived stress (β=-0.25, pacademic stress (β=0.34, phelp to reduce stress for dental students and, through their effect on exam-related self-efficacy appraisals, contribute to improved academic performance. PMID:26834134

  4. Role of wheat germ oil in radiation-induced oxidative stress and alteration in energy metabolism in rats

    International Nuclear Information System (INIS)

    The liver is essential in keeping the body functioning properly while muscular strength is important in sport as well as in daily activities. Exposure to ionizing radiation is thought to increase oxidative stress and damage liver and muscle tissues. Wheat germ oil is a natural unrefined vegetable oil. It is an excellent source of vitamin E, octacosanol, linoleic and linolenic essential fatty acids, which may be beneficial in neutralizing the free oxygen radicals. This study was designed to investigate the efficacy of wheat germ oil, on radiation induced oxidative damage in rat's liver and skeletal muscle. Wheat germ oil was supplemented orally via gavage to rats at a dose of 54 mg/ kg body weight for 14 successive days pre- and 7 days post-exposure to 5 Gy (single dose) of whole body gamma irradiation. Animals were sacrificed 7, 14 and 21 days post radiation exposure. The results revealed that whole body gamma irradiation of rats induces oxidative stress in liver and skeletal muscles obvious by significant elevation in the levels of xanthine oxidase and thiobarbituric acid reactive substances (TBARS) associated with significant decreases in the content of reduced glutathione, as well as decreases in xanthine dehydrogenase, superoxide dismutase, catalase and glutathione peroxidase activities. Irradiated rats showed also significant decreases in creatine phosphokinase, glutamate dehydrogenase and glucose-6- phosphate dehydrogenase activities while lactate dehydrogenase were significantly increased. Total iron, total copper and total calcium levels significantly increased in the liver and skeletal muscles of irradiated rats group compared to control group. Wheat germ oil treated-irradiated rats showed significantly less severe damage and remarkable improvement in all the measured parameters, compared to irradiated rats. It could be concluded that wheat germ oil by attenuating radiation-induced oxidative stress might play a role in maintaining liver and skeletal muscle

  5. Exercise-induced alterations in pancreatic oxidative stress and mitochondrial function in type 2 diabetic Goto-Kakizaki rats.

    Science.gov (United States)

    Raza, Haider; John, Annie; Shafarin, Jasmin; Howarth, Frank C

    2016-04-01

    Progressive metabolic complications accompanied by oxidative stress are the hallmarks of type 2 diabetes. The precise molecular mechanisms of the disease complications, however, remain elusive. Exercise-induced nontherapeutic management of type 2 diabetes is the first line of choice to control hyperglycemia and diabetes associated complications. In this study, using 11-month-old type 2 Goto-Kakizaki (GK) rats, we have investigated the effects of exercise on mitochondrial metabolic and oxidative stress in the pancreas. Our results showed an increase in theNADPHoxidase enzyme activity and reactive oxygen species (ROS) production inGKrats, which was inhibited after exercise. Increased lipid peroxidation and protein carbonylation andSODactivity were also inhibited after exercise. Interestingly, glutathione (GSH) level was markedly high in the pancreas ofGKdiabetic rats even after exercise. However,GSH-peroxidase andGSH-reductase activities were significantly reduced. Exercise also induced energy metabolism as observed by increased hexokinase and glutamate dehydrogenase activities. A significant decrease in the activities of mitochondrial ComplexesII/IIIandIVwere observed in theGKrats. Exercise improved only ComplexIVactivity suggesting increased utilization of oxygen. We also observed increased activities of cytochrome P450s in the pancreas ofGKrats which was reduced significantly after exercise.SDS-PAGEresults have shown a decreased expression ofNF-κB, Glut-2, andPPAR-ϒ inGKrats which was markedly increased after exercise. These results suggest differential oxidative stress and antioxidant defense responses after exercise. Our results also suggest improved mitochondrial function and energy utilization in the pancreas of exercisingGKrats. PMID:27095835

  6. Altered lipid peroxidation markers are related to post-traumatic stress disorder (PTSD) and not trauma itself in earthquake survivors.

    Science.gov (United States)

    Atli, Abdullah; Bulut, Mahmut; Bez, Yasin; Kaplan, İbrahim; Özdemir, Pınar Güzel; Uysal, Cem; Selçuk, Hilal; Sir, Aytekin

    2016-06-01

    The traumatic life events, including earthquakes, war, and interpersonal conflicts, cause a cascade of psychological and biological changes known as post-traumatic stress disorder (PTSD). Malondialdehyde (MDA) is a reliable marker of lipid peroxidation, and paraoxonase is a known antioxidant enzyme. The aims of this study were to investigate the relationship between earthquake trauma, PTSD effects on oxidative stress and the levels of serum paraoxonase 1 (PON1) enzyme activity, and levels of serum MDA. The study was carried out on three groups called: the PTSD group, the traumatized with earthquake exercise group, and healthy control group, which contained 32, 31, and 38 individuals, respectively. Serum MDA levels and PON1 enzyme activities from all participants were measured, and the results were compared across all groups. There were no significant differences between the PTSD patients and non-PTSD earthquake survivors in terms of the study variables. The mean PON1 enzyme activity from PTSD patients was significantly lower, while the mean MDA level was significantly higher than that of the healthy control group (p earthquake survivors who did not develop PTSD showed higher MDA levels and lower PON1 activity when compared to healthy controls. However, the differences between these groups did not reach a statistically significant level. Increased MDA level and decreased PON1 activity measured in PTSD patients after earthquake and may suggest increased oxidative stress in these patients. The nonsignificant trends that are observed in lipid peroxidation markers of earthquake survivors may indicate higher impact of PTSD development on these markers than trauma itself. For example, PTSD diagnosis seems to add to the effect of trauma on serum MDA levels and PON1 enzyme activity. Thus, serum MDA levels and PON1 enzyme activity may serve as biochemical markers of PTSD diagnosis. PMID:26324882

  7. Morbillivirus glycoprotein expression induces ER stress, alters Ca2+ homeostasis and results in the release of vasostatin.

    Directory of Open Access Journals (Sweden)

    Jean-Marc Brunner

    Full Text Available Although the pathology of Morbillivirus in the central nervous system (CNS is well described, the molecular basis of neurodegenerative events still remains poorly understood. As a model to explore Morbillivirus-mediated CNS dysfunctions, we used canine distemper virus (CDV that we inoculated into two different cell systems: a monkey cell line (Vero and rat primary hippocampal neurons. Importantly, the recombinant CDV used in these studies not only efficiently infects both cell types but recapitulates the uncommon, non-cytolytic cell-to-cell spread mediated by virulent CDVs in brain of dogs. Here, we demonstrated that both CDV surface glycoproteins (F and H markedly accumulated in the endoplasmic reticulum (ER. This accumulation triggered an ER stress, characterized by increased expression of the ER resident chaperon calnexin and the proapoptotic transcription factor CHOP/GADD 153. The expression of calreticulin (CRT, another ER resident chaperon critically involved in the response to misfolded proteins and in Ca(2+ homeostasis, was also upregulated. Transient expression of recombinant CDV F and H surface glycoproteins in Vero cells and primary hippocampal neurons further confirmed a correlation between their accumulation in the ER, CRT upregulation, ER stress and disruption of ER Ca(2+ homeostasis. Furthermore, CDV infection induced CRT fragmentation with re-localisation of a CRT amino-terminal fragment, also known as vasostatin, on the surface of infected and neighbouring non-infected cells. Altogether, these results suggest that ER stress, CRT fragmentation and re-localization on the cell surface may contribute to cytotoxic effects and ensuing cell dysfunctions triggered by Morbillivirus, a mechanism that might potentially be relevant for other neurotropic viruses.

  8. Characterizing dose response relationships: Chronic gamma radiation in Lemna minor induces oxidative stress and altered polyploidy level.

    Science.gov (United States)

    Van Hoeck, Arne; Horemans, Nele; Van Hees, May; Nauts, Robin; Knapen, Dries; Vandenhove, Hildegarde; Blust, Ronny

    2015-12-01

    The biological effects and interactions of different radiation types in plants are still far from understood. Among different radiation types, external gamma radiation treatments have been mostly studied to assess the biological impact of radiation toxicity in organisms. Upon exposure of plants to gamma radiation, ionisation events can cause, either directly or indirectly, severe biological damage to DNA and other biomolecules. However, the biological responses and oxidative stress related mechanisms under chronic radiation conditions are poorly understood in plant systems. In the following study, it was questioned if the Lemna minor growth inhibition test is a suitable approach to also assess the radiotoxicity of this freshwater plant. Therefore, L. minor plants were continuously exposed for seven days to 12 different dose rate levels covering almost six orders of magnitude starting from 80 μGy h(-1) up to 1.5 Gy h(-1). Subsequently, growth, antioxidative defence system and genomic responses of L. minor plants were evaluated. Although L. minor plants could survive the exposure treatment at environmental relevant exposure conditions, higher dose rate levels induced dose dependent growth inhibitions starting from approximately 27 mGy h(-1). A ten-percentage growth inhibition of frond area Effective Dose Rate (EDR10) was estimated at 95 ± 7 mGy h(-1), followed by 153 ± 13 mGy h(-1) and 169 ± 12 mGy h(-1) on fresh weight and frond number, respectively. Up to a dose rate of approximately 5 mGy h(-1), antioxidative enzymes and metabolites remained unaffected in plants. A significant change in catalase enzyme activity was found at 27 mGy h(-1) which was accompanied with significant increases of other antioxidative enzyme activities and shifts in ascorbate and glutathione content at higher dose rate levels, indicating an increase in oxidative stress in plants. Recent plant research hypothesized that environmental genotoxic stress conditions

  9. Metallothionein-I plus II and receptor megalin are altered in relation to oxidative stress in cerebral lymphomas

    DEFF Research Database (Denmark)

    Pedersen, M.O.; Hansen, P.B.; Nielsen, Signe Ledou;

    2010-01-01

    Primary central nervous system lymphoma (PCNSL) in immunocompetent patients is highly malignant and has a poor prognosis. The PCNSL molecular features are reminiscent to some degree of diffuse large B-cell lymphoma (DLBCL), yet PCNSL shows unique molecular profiles and a distinct clinical behavior....... This article characterizes the histopathology and expression profiles of metallothionein-I + II (MT-I + II) and their receptor megalin along with proliferation, oxidative stress, and apoptosis in PCNSL and in central nervous system (CNS) lymphomas due to relapse from DLBCL (collectively referred to as...

  10. Serum leptin and cortisol, related to acutely perceived academic examination stress and performance in female university students.

    Science.gov (United States)

    Haleem, Darakhshan J; Inam, Qurrat-Ul-Aen; Haider, Saida; Perveen, Tahira; Haleem, Muhammad Abdul

    2015-12-01

    Leptin, identified as an antiobesity hormone, also has important role in responses to stress and processing of memory. This study was designed to determine effects of academic examination stress-induced changes in serum leptin and its impact on academic performance. Eighty five healthy female students (age 19-21 years; BMI 21.9 ± 1.6) were recruited for the study. Serum leptin and cortisol were monitored at base line (beginning of academic session) and on the day of examination; using a standardized ELISA kit. Acute perception of academic examination stress was determined with the help of a questionnaire derived from Hamilton Anxiety Scale and self report of stress perception. Academic performance was evaluated by the percentage of marks obtained in the examination. Serum cortisol levels were positively correlated (p < 0.01) with the subjective perception of examination stress but not with academic performance. There was an inverted U-shape relationship between level of stress and academic performance. Leptin increased in all stress groups and correlated (p < 0.01) positively with academic performance. There was an inverted U-shape relationship between level of stress and circulating leptin. The findings suggest the peptide hormone, leptin, is a biomarker of stress perception and a mediator of facilitating effects of stress on cognition. PMID:26187200

  11. Workplace stress, job satisfaction, job performance, and turnover intention of health care workers in rural Taiwan.

    Science.gov (United States)

    Chao, Ming-Che; Jou, Rong-Chang; Liao, Cing-Chu; Kuo, Chung-Wei

    2015-03-01

    Workplace stress (WS) has been found to affect job satisfaction (JS), performance, and turnover intentions (TIs) in developed countries, but there is little evidence from other countries and especially rural areas. In rural Taiwan, especially, there is an insufficient health care workforce, and the situation is getting worse. To demonstrate the relationship, we used a cross-sectional structured questionnaire, and data from 344 licensed professionals in 1 rural regional hospital were analyzed using the structural equation model. The results showed that WS had a positive effect on both TI and job performance (JP) but a negative effect on satisfaction. JS did improve performance. For the staff with an external locus of control, stress affected JP and satisfaction significantly. For the staff with lower perceived job characteristics, JS affected performance significantly. The strategies to decrease stress relating to work load, role conflict, family factors, and working environment should be focused and implemented urgently to lower the turnover rate of health care workers in rural Taiwan. PMID:24174390

  12. Stress

    DEFF Research Database (Denmark)

    Keller, Hanne Dauer

    2015-01-01

    Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb.......Kapitlet handler om stress som følelse, og det trækker primært på de få kvalitative undersøgelser, der er lavet af stressforløb....

  13. Stress-Induced Isoforms of MDM2 and MDM4 Correlate with High-Grade Disease and an Altered Splicing Network in Pediatric Rhabdomyosarcoma

    Directory of Open Access Journals (Sweden)

    Aishwarya G. Jacob

    2013-09-01

    Full Text Available Pediatric rhabdomyosarcoma (RMS is a morphologically and genetically heterogeneous malignancy commonly classified into three histologic subtypes, namely, alveolar, embryonal, and anaplastic. An issue that continues to challenge effective RMS patient prognosis is the dearth of molecular markers predictive of disease stage irrespective of tumor subtype. Our study involving a panel of 70 RMS tumors has identified specific alternative splice variants of the oncogenes Murine Double Minute 2 (MDM2 and MDM4 as potential biomarkers for RMS. Our results have demonstrated the strong association of genotoxic-stress inducible splice forms MDM2-ALT1 (91.6% Intergroup Rhabdomyosarcoma Study Group stage 4 tumors and MDM4-ALT2 (90.9% MDM4-ALT2-positive T2 stage tumors with high-risk metastatic RMS. Moreover, MDM2-ALT1-positive metastatic tumors belonged to both the alveolar (50% and embryonal (41.6% subtypes, making this the first known molecular marker for high-grade metastatic disease across the most common RMS subtypes. Furthermore, our results show that MDM2-ALT1 expression can function by directly contribute to metastatic behavior and promote the invasion of RMS cells through a matrigel-coated membrane. Additionally, expression of both MDM2-ALT1 and MDM4-ALT2 increased anchorage-independent cell-growth in soft agar assays. Intriguingly, we observed a unique coordination in the splicing of MDM2-ALT1 and MDM4-ALT2 in approximately 24% of tumor samples in a manner similar to genotoxic stress response in cell lines. To further explore splicing network alterations with possible relevance to RMS disease, we used an exon microarray approach to examine stress-inducible splicing in an RMS cell line (Rh30 and observed striking parallels between stress-responsive alternative splicing and constitutive splicing in RMS tumors.

  14. Alteration of oxidative stress parameters in red blood cells of rats after chronic in vivo treatment with cisplatin and selenium

    Directory of Open Access Journals (Sweden)

    Marković Snežana D.

    2011-01-01

    Full Text Available In this study we evaluated the possible protective effects of selenium (Se on hematological and oxidative stress parameters in rats chronically treated with cisplatin (cisPt. Four groups of Wistar albino rats were examined: a control, untreated rats (I, rats treated with Se (II, rats treated with cisPt (III, and rats treated with Se and cisPt (IV. All animals were treated for 5 days successively and killed 24 h after the last treatment. Hematological and oxidative stress parameters were followed in whole blood and red blood cells (RBC. Results showed that the chronic application of Se was followed by a higher number of reticulocytes and platelets, increased lipid peroxidation and GSH content in the RBC. Cisplatin treatment induced depletion of RBC and platelet numbers and an elevation of the superoxide anion, nitrites and glutathione levels. Se and cisPt co-treatment was followed by an elevation of the hematological parameters and the recovery of the glutathione status when compared to the control and cisPt-treated rats.

  15. 17β-Estradiol alters oxidative damage and oxidative stress response protein expression in the mouse mammary gland.

    Science.gov (United States)

    Yuan, Lisi; Dietrich, Alicia K; Ziegler, Yvonne S; Nardulli, Ann M

    2016-05-01

    Although substantial evidence has demonstrated that parity and 17β-estradiol (E2) reduce mammary carcinogenesis, it is not clear how this protection is conferred. Thus, we examined the effects of parity and E2 treatment in the mammary glands of ovariectomized 15 week-old virgin mice, 15 week-old primiparous mice, and 9 month-old retired breeders. E2 treatment significantly increased lipid peroxidation, protein carbonylation, and protein nitrosylation in the virgin mice, but not in the age-matched primiparous mice or retired breeders. Mammary gland expression of the oxidative stress response protein Cu/Zn superoxide dismutase was consistently reduced in all of the E2-treated mice regardless of parity. Expression of the oxidative stress and DNA repair protein apurinic endonuclease (Ape1) was significantly increased only in the mammary glands of the E2-treated retired breeders. These findings suggest that E2 and parity help to reduce mammary oncogenesis by maintaining the structure and function of proteins, lipids, and DNA. PMID:26872614

  16. PEP3 overexpression shortens lag phase but does not alter growth rate in Saccharomyces cerevisiae exposed to acetic acid stress.

    Science.gov (United States)

    Ding, Jun; Holzwarth, Garrett; Bradford, C Samuel; Cooley, Ben; Yoshinaga, Allen S; Patton-Vogt, Jana; Abeliovich, Hagai; Penner, Michael H; Bakalinsky, Alan T

    2015-10-01

    In fungi, two recognized mechanisms contribute to pH homeostasis: the plasma membrane proton-pumping ATPase that exports excess protons and the vacuolar proton-pumping ATPase (V-ATPase) that mediates vacuolar proton uptake. Here, we report that overexpression of PEP3 which encodes a component of the HOPS and CORVET complexes involved in vacuolar biogenesis, shortened lag phase in Saccharomyces cerevisiae exposed to acetic acid stress. By confocal microscopy, PEP3-overexpressing cells stained with the vacuolar membrane-specific dye, FM4-64 had more fragmented vacuoles than the wild-type control. The stained overexpression mutant was also found to exhibit about 3.6-fold more FM4-64 fluorescence than the wild-type control as determined by flow cytometry. While the vacuolar pH of the wild-type strain grown in the presence of 80 mM acetic acid was significantly higher than in the absence of added acid, no significant difference was observed in vacuolar pH of the overexpression strain grown either in the presence or absence of 80 mM acetic acid. Based on an indirect growth assay, the PEP3-overexpression strain exhibited higher V-ATPase activity. We hypothesize that PEP3 overexpression provides protection from acid stress by increasing vacuolar surface area and V-ATPase activity and, hence, proton-sequestering capacity. PMID:26051671

  17. Faculty's Job Stress and Performance in the Undergraduate Education Assessment in China: A Mixed-Methods Study

    Science.gov (United States)

    Jing, Lizhen

    2008-01-01

    The Undergraduate Education Assessment (assessment) was launched to upgrade faculty's performance, but it also tends to intensify their job stress. Considering the little empirical research on the influence of stress on performance in the assessment and the confounded findings in literature, the study collected data with a survey and interviews to…

  18. Water Stress Modulates Soybean Aphid Performance, Feeding Behavior, and Virus Transmission in Soybean

    Science.gov (United States)

    Nachappa, Punya; Culkin, Christopher T.; Saya, Peter M.; Han, Jinlong; Nalam, Vamsi J.

    2016-01-01

    Little is known about how water stress including drought and flooding modifies the ability of plants to resist simultaneous attack by insect feeding and transmission of insect-vectored pathogen. We analyzed insect population growth, feeding behaviors, virus transmission, and plant amino acid profiles and defense gene expression to characterize mechanisms underlying the interaction between water stress, soybean aphid and aphid-transmitted, Soybean mosaic virus, on soybean plants. Population growth of non-viruliferous aphids was reduced under drought stress and saturation, likely because the aphids spent less time feeding from the sieve element on these plants compared to well-watered plants. Water stress did not impact population growth of viruliferous aphids. However, virus incidence and transmission rate was lowest under drought stress and highest under saturated conditions since viruliferous aphids took the greatest amount time to puncture cells and transmit the virus under saturated conditions and lowest time under drought stress. Petiole exudates from drought-stressed plants had the highest level of total free amino acids including asparagine and valine that are critical for aphid performance. Aphids did not benefit from improved phloem sap quality as indicated by their lower densities on drought-stressed plants. Saturation, on the other hand, resulted in low amino acid content compared to all of the other treatments. Drought and saturation had significant and opposing effects on expression of marker genes involved in abscisic acid (ABA) signaling. Drought alone significantly increased expression of ABA marker genes, which likely led to suppression of salicylic acid (SA)- and jasmonic acid (JA)-related genes. In contrast, ABA marker genes were down-regulated under saturation, while expression of SA- and JA-related genes was up-regulated. We propose that the apparent antagonism between ABA and SA/JA signaling pathways contributed to an increase in aphid

  19. Altered cardiovascular reactivity and osmoregulation during hyperosmotic stress in adult rats developmentally exposed to polybrominated diphenyl ethers (PBDEs)

    International Nuclear Information System (INIS)

    Polybrominated diphenyl ethers (PBDEs) and the structurally similar chemicals polychlorinated biphenyls (PCBs) disrupt the function of multiple endocrine systems. PCBs and PBDEs disrupt the secretion of vasopressin (VP) from the hypothalamus during osmotic activation. Since the peripheral and central vasopressinergic axes are critical for osmotic and cardiovascular regulation, we examined whether perinatal PBDE exposure could impact these functions during physiological activation. Rats were perinatally dosed with a commercial PBDE mixture, DE-71. Dams were given 0 (corn oil control), 1.7 (low dose) or 30.6 mg/kg/day (high dose) in corn oil from gestational day (GD) 6 through postnatal day (PND) 21 by oral gavage. In the male offspring exposed to high dose PBDE plasma thyroxine and triiodothyronine levels were reduced at PND 21 and recovered to control levels by PND 60 when thyroid stimulating hormone levels were elevated. At 14-18 months of age, cardiovascular responses were measured in four groups of rats: Normal (Oil, normosmotic condition), Hyper (Oil, hyperosmotic stress), Hyper PBDE low (1.7 mg/kg/day DE-71 perinatally, hyperosmotic stress), and Hyper PBDE high (30.6 mg/kg/day DE-71 perinatally, hyperosmotic stress). Systolic blood pressure (BP), diastolic BP, and heart rate (HR) were determined using tail cuff sphygmomanometry and normalized to pretreatment values (baseline) measured under basal conditions. Hyperosmotic treatment yielded significant changes in systolic BP in PBDE exposed rats only. Hyper PBDE low and high dose rats showed 36.1 and 64.7% greater systolic BP responses at 3 h post hyperosmotic injection relative to pretreatment baseline, respectively. No treatment effects were measured for diastolic BP and HR. Hyper and Hyper PBDE rats showed increased mean plasma osmolality values by 45 min after injection relative to normosmotic controls. In contrast to Hyper rats, Hyper PBDE (high) rats showed a further increase in mean plasma osmolality at 3

  20. Does low-protein diet improve broiler performance under heat stress conditions?

    OpenAIRE

    RL Furlan; DE Faria Filho; PS Rosa; M Macari

    2004-01-01

    Nutrition for broilers under high temperatures is extremely important for brazilian broiler chicken industry because the amounts of consumed nutrients and environmental temperature have great effects on bird performance and carcass quality. Among diet nutrients, protein has the highest heat increment; thus, during many years, diets with low protein level were recommended in order to reduce heat production in broiler chickens under heat stress. However, reports have shown that low-protein diet...

  1. Impact of heat stress on health and performance of dairy animals: A review

    OpenAIRE

    Ramendra Das; Lalrengpuii Sailo; Nishant Verma; Pranay Bharti; Jnyanashree Saikia; Imtiwati; Rakesh Kumar

    2016-01-01

    Sustainability in livestock production system is largely affected by climate change. An imbalance between metabolic heat production inside the animal body and its dissipation to the surroundings results to heat stress (HS) under high air temperature and humid climates. The foremost reaction of animals under thermal weather is increases in respiration rate, rectal temperature and heart rate. It directly affect feed intake thereby, reduces growth rate, milk yield, reproductive performance, and ...

  2. Effects of supplementation of betaine hydrochloride on physiological performances of broilers exposed to thermal stress

    OpenAIRE

    Haldar, Sudipto

    2015-01-01

    Abhay K Singh,1 Tapan K Ghosh,1 David C Creswell,2 Sudipto Haldar1 1Department of Animal Nutrition, Faculty of Veterinary and Animal Sciences, West Bengal University of Animal and Fishery Sciences, Kolkata, India; 2Creswell Nutrition, Sydney, Australia Background: Betaine has the potential to spare methionine and choline as methyl-group donors, and is thought to improve broiler performance under conditions of stress. An experiment was conducted to ascertain the effects of supplemental betain...

  3. Do symbiotic microbes have a role in plant evolution, performance and response to stress?

    OpenAIRE

    Barrow, Jerry R; Mary E Lucero; Reyes-Vera, Isaac; Havstad, Kris M.

    2008-01-01

    Vascular plants have been considered as autonomous organisms especially when their performance has been interpreted at the genome and cellular level. In reality, vascular plants provide a unique ecological niche for diverse communities of cryptic symbiotic microbes which often contribute multiple benefits, such as enhanced photosynthetic efficiency, nutrient and water use and tolerance to abiotic and biotic stress. These benefits are similar to improvements sought by plant scientists working ...

  4. Evaluation of cytotoxicity, morphological alterations and oxidative stress in Chinook salmon cells exposed to copper oxide nanoparticles.

    Science.gov (United States)

    Srikanth, Koigoora; Pereira, Eduarda; Duarte, Armando C; Rao, Janapala Venkateswara

    2016-05-01

    The current study is aimed to study cytotoxicity and oxidative stress mediated changes induced by copper oxide nanoparticles (CuO NPs) in Chinook salmon cells (CHSE-214). To this end, a number of biochemical responses are evaluated in CHSE-214 cells which are as follows [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide] MTT, neutral red uptake (NRU), lactate dehydrogenase (LDH), protein carbonyl (PC), lipid peroxidation (LPO), oxidised glutathione (GSSG), reduced glutathione (GSH), glutathione peroxidase (GPx), glutathione sulfo-transferase (GST), superoxide dismutase (SOD), catalase (CAT), 8-Hydroxy-2'-deoxyguanosine (8-OHdG) and reactive oxygen species (ROS), respectively. The 50 % inhibition concentration (IC50) of CuO NPs to CHSE-214 cells after 24 h exposure was found to be 19.026 μg ml(-1). Viability of cells was reduced by CuO NPs, and the decrease was dose dependent as revealed by the MTT and NRU assay. CHSE-214 cells exposed to CuO NPs induced morphological changes. Initially, cells started to detach from the surface (12 h), followed by polyhedric, fusiform appearance (19 h) and finally the cells started to shrink. Later, the cells started losing their cellular contents leading to their death only after 24 h. LDH, PC, LPO, GSH, GPx, GST, SOD, CAT, 8-OHdG and ROS responses were seen significantly increased with the increase in the concentration of CuO NPs when compared to their respective controls. However, significant decrease in GSSG was perceptible in CHSE-214 cells exposed to CuO NPs in a dose-dependent manner. Our data demonstrated that CuO NPs induced cytotoxicity in CHSE-214 cells through the mediation of oxidative stress. The current study provides a baseline for the CuO NPs-mediated cytotoxic assessment in CHSE-214 cells for the future studies. PMID:26115719

  5. A case study to determine stress sources affecting the academic performance

    Directory of Open Access Journals (Sweden)

    Aytaç Aydın

    2011-07-01

    Full Text Available 800x600 Normal 0 21 false false false TR X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Normal Tablo"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";} Job stress affects academicians in terms of performance, scientific production, job satisfaction and health. This effect may differ according to the academicians in the structure of the organization. It is possible to mention about positive stress if organization structure positively affects academician, but it is called negative stress if it negatively affects. Lack of fee and powers, injustice employee evaluation, not getting in return for work are important stress sources. In this study, some of the factors that affect stress levels (individual, organizational and physical environmental factors of academicians (professors, associate professors and assistant professors who work in Karadeniz Technical University are investigated by questionnaire method. The survey data is evaluated with Structural Equation Model (SEM which is prepared in statistical package programs SPSS 16.0 and AMOS 16.0 and the results are revealed. As a result, factors effecting academic members' stress levels are determined as individual and organizational factors (p<0,1. Thus, it is concluded that physical environmental factors such as noise, lightening and crowded place do not cause tension on academician

  6. Orbitofrontal cortex 5-HT2A receptor mediates chronic stress-induced depressive-like behaviors and alterations of spine density and Kalirin7.

    Science.gov (United States)

    Xu, Chang; Ma, Xin-Ming; Chen, Hui-Bin; Zhou, Meng-He; Qiao, Hui; An, Shu-Cheng

    2016-10-01

    Neuroimaging studies show that patients with major depression have reduced volume of the orbitofrontal cortex (OFC). Although the serotonin (5-HT) 2A receptor, which is abundant in the OFC, has been implicated in depression, the underlying mechanisms in the development of stress-induced depression remain unclear. Kalirin-7 (Kal7) is an essential component of mature excitatory synapses for maintaining dendritic spines density, size and synaptic functions. The aim of this study was to investigate the role of orbitofrontal 5-HT and 5-HT2A receptors in depressive-like behaviors and their associations with Kal7 and dendritic spines using chronic unpredictable mild stress (CUMS), an established animal model of depression. CUMS had no effect on the levels of 5-HT or the 5-HT2A receptor in the OFC. However, CUMS or microinjection of the 5-HT2A/2C receptor agonist (±)-1-(2, 5-Dimethoxy-4-iodophenyl)- 2-aminopropane hydrochloride (DOI, 5 μg/0.5 μL) into the OFC induced depressive-like behaviors, including anhedonia in the sucrose preference test and behavioral despair in the tail suspension test, a significant reduction in body weight gain and locomotor activity in the open field test, which were accompanied by decreased expression of Kal7 and PSD95 as well as decreased density of dendritic spines in the OFC. These alterations induced by CUMS were reversed by pretreatment with the 5-HT2A receptor antagonist Ketanserin (Ket, 5 μg/0.5 μL into the OFC). These results suggest that CUMS alters structural plasticity through activation of the orbital 5-HT2A receptor and is associated with decreased expression of Kal7, thereby resulting in depressive-like behaviors in rats, suggesting an important role of Kal7 in the OFC in depression. PMID:26921771

  7. The surfactant protein C mutation A116D alters cellular processing, stress tolerance, surfactant lipid composition, and immune cell activation

    Directory of Open Access Journals (Sweden)

    Zarbock Ralf

    2012-03-01

    Full Text Available Abstract Background Surfactant protein C (SP-C is important for the function of pulmonary surfactant. Heterozygous mutations in SFTPC, the gene encoding SP-C, cause sporadic and familial interstitial lung disease (ILD in children and adults. Mutations mapping to the BRICHOS domain located within the SP-C proprotein result in perinuclear aggregation of the proprotein. In this study, we investigated the effects of the mutation A116D in the BRICHOS domain of SP-C on cellular homeostasis. We also evaluated the ability of drugs currently used in ILD therapy to counteract these effects. Methods SP-CA116D was expressed in MLE-12 alveolar epithelial cells. We assessed in vitro the consequences for cellular homeostasis, immune response and effects of azathioprine, hydroxychloroquine, methylprednisolone and cyclophosphamide. Results Stable expression of SP-CA116D in MLE-12 alveolar epithelial cells resulted in increased intracellular accumulation of proSP-C processing intermediates. SP-CA116D expression further led to reduced cell viability and increased levels of the chaperones Hsp90, Hsp70, calreticulin and calnexin. Lipid analysis revealed decreased intracellular levels of phosphatidylcholine (PC and increased lyso-PC levels. Treatment with methylprednisolone or hydroxychloroquine partially restored these lipid alterations. Furthermore, SP-CA116D cells secreted soluble factors into the medium that modulated surface expression of CCR2 or CXCR1 receptors on CD4+ lymphocytes and neutrophils, suggesting a direct paracrine effect of SP-CA116D on neighboring cells in the alveolar space. Conclusions We show that the A116D mutation leads to impaired processing of proSP-C in alveolar epithelial cells, alters cell viability and lipid composition, and also activates cells of the immune system. In addition, we show that some of the effects of the mutation on cellular homeostasis can be antagonized by application of pharmaceuticals commonly applied in ILD therapy

  8. Characterization and modelling of fluid flows in fissured and fractured media. relation with hydrothermal alterations and paleo-stress quantification; Caracterisation et modelisation des ecoulements fluides en milieu fissure. relation avec les alterations hydrothermales et quantification des paleocontraintes

    Energy Technology Data Exchange (ETDEWEB)

    Sausse, J.

    1998-10-15

    the modelization of the space-time evolution of the Brezouard granite crack permeability during fluid-rock interactions. The two used permeability models (geometrical or statistical) remain very dependent on the definition of the characteristic opening of fracture or fissure. Real fractures in a rocky mass are characterised by non parallel, flat and thus overlapped walls. The study of these natural fracture surfaces at micro and macroscopic scale is completed by a theoretical modelization of their hydro-mechanical behaviour. This work indicates the influence of the surface roughness on the fluid flow as well as the propagation of the alteration. These fractures were formed and percolated under a particular tectonic regime that controls their orientation. Numerous quartz veins in the Soultz granite are opened and sealed during the Oligocene extension. The characteristic fluid pressure of these opening - sealing stages are quantified thanks to fluid inclusion studies. These inclusions are located in secondary quartz which seal the veins. A new method of paleo-stress quantification is proposed, based on the knowledge of this fluid pressure. It takes i) the geometrical distribution of the vein poles, ii) some empirical considerations of rupture criteria, and iii) the fluid pressures into account. (author)

  9. Effects of cerium dioxide nanoparticles in Oncorhynchus mykiss liver after an acute exposure: assessment of oxidative stress, genotoxicity and histological alterations

    Directory of Open Access Journals (Sweden)

    Ana Cristina Nunes

    2015-12-01

    Full Text Available At present cerium oxide nanoparticles (CeO2 NP have numerous applications ranging from industry to the household, leading to its wide distribution namely in the aquatic environment. The hereby study aimed to assess the toxic effects of CeO2 NPs in Oncorhynchus mykiss liver following an acute exposure (96h to three different concentrations (0.25, 2.5 and 25 mg/L in terms of the genotoxicity (comet assay, oxidative stress response (Catalase CAT; Glutathione S-Transferases GSTs; Thiobarbituric Acid Reactive Substances TBARS and histopathology. CeO2 NP exposure resulted in genotoxic damage in all exposure treatments, inhibition of CAT in the highest concentration and histopathological changes in all exposure concentrations with predominance of progressive and circulatory alterations. However TBARS and GSTs showed no significant differences comparatively to the control (unexposed group. The results suggest that CeO2 NP are able to cause genotoxicity, biochemical impairment and histological alterations in the liver of rainbow trout.

  10. Pre-Exercise Hyperhydration-Induced Bodyweight Gain Does Not Alter Prolonged Treadmill Running Time-Trial Performance in Warm Ambient Conditions

    Directory of Open Access Journals (Sweden)

    Eric D. B. Goulet

    2012-08-01

    Full Text Available This study compared the effect of pre-exercise hyperhydration (PEH and pre-exercise euhydration (PEE upon treadmill running time-trial (TT performance in the heat. Six highly trained runners or triathletes underwent two 18 km TT runs (~28 °C, 25%–30% RH on a motorized treadmill, in a randomized, crossover fashion, while being euhydrated or after hyperhydration with 26 mL/kg bodyweight (BW of a 130 mmol/L sodium solution. Subjects then ran four successive 4.5 km blocks alternating between 2.5 km at 1% and 2 km at 6% gradient, while drinking a total of 7 mL/kg BW of a 6% sports drink solution (Gatorade, USA. PEH increased BW by 1.00 ± 0.34 kg (P < 0.01 and, compared with PEE, reduced BW loss from 3.1% ± 0.3% (EUH to 1.4% ± 0.4% (HYP (P < 0.01 during exercise. Running TT time did not differ between groups (PEH: 85.6 ± 11.6 min; PEE: 85.3 ± 9.6 min, P = 0.82. Heart rate (5 ± 1 beats/min and rectal (0.3 ± 0.1 °C and body (0.2 ± 0.1 °C temperatures of PEE were higher than those of PEH (P < 0.05. There was no significant difference in abdominal discomfort and perceived exertion or heat stress between groups. Our results suggest that pre-exercise sodium-induced hyperhydration of a magnitude of 1 L does not alter 80–90 min running TT performance under warm conditions in highly-trained runners drinking ~500 mL sports drink during exercise.

  11. Altered regional homogeneity with short-term simulated microgravity and its relationship with changed performance in mental transformation.

    Directory of Open Access Journals (Sweden)

    Yang Liao

    Full Text Available In order to further the insight into the explanation of changed performance in mental transformation under microgravity, we discuss the change of performance in mental transformation and its relationship with altered regional homogeneity (ReHo in resting-state brain by using simulated weightlessness model. Twelve male subjects with age between 24 and 31 received resting-state fMRI scan and mental transformation test both in normal condition and immediately after 72 hours -6° head down tilt (HDT. A paired sample t-test was used to test the difference of behavior performance and brain activity between these two conditions. Compare with normal condition, subjects showed a changed performance in mental transformation with short term simulated microgravity and appeared to be falling. Meanwhile, decreased ReHo were found in right inferior frontal gyrus (IFG and left inferior parietal lobule (IPL after 72 hours -6° HDT, while increased ReHo were found in bilateral medial frontal gyrus (MFG and left superior frontal gyrus (SFG (P<0.05, corrected. Particularly, there was a significant correlation between ReHo values in left IPL and velocity index of mental transformation. Our findings indicate that gravity change may disrupt the function of right IFG and left IPL in the resting-state, among of which functional change in left IPL may contribute to changed abilities of mental transformation. In addition, the enhanced activity of the bilateral MFG and decreased activity of right IFG found in the current study maybe reflect a complementation effect on inhibitory control process.

  12. Neonatal exposure to benzo[a]pyrene induces oxidative stress causing altered hippocampal cytomorphometry and behavior during early adolescence period of male Wistar rats.

    Science.gov (United States)

    Patel, Bhupesh; Das, Saroj Kumar; Das, Swagatika; Das, Lipsa; Patri, Manorama

    2016-05-01

    Environmental neurotoxicants like benzo[a]pyrene (B[a]P) have been well documented regarding their potential to induce oxidative stress. However, neonatal exposure to B[a]P and its subsequent effect on anti-oxidant defence system and hippocampal cytomorphometry leading to behavioral changes have not been fully elucidated. We investigated the effect of acute exposure of B[a]P on five days old male Wistar pups administered with single dose of B[a]P (0.2 μg/kg BW) through intracisternal mode. Control group was administered with vehicle i.e., DMSO and a separate group of rats without any treatment was taken as naive group. Behavioral analysis showed anxiolytic-like behavior with significant increase in time spent in open arm in elevated plus maze. Further, significant reduction in fall off time during rotarod test showing B[a]P induced locomotor hyperactivity and impaired motor co-ordination in adolescent rats. B[a]P induced behavioral changes were further associated with altered anti-oxidant defence system involving significant reduction in the total ATPase, Na(+) K(+) ATPase, Mg(2+) ATPase, GR and GPx activity with a significant elevation in the activity of catalase and GST as compared to naive and control groups. Cytomorphometry of hippocampus showed that the number of neurons and glia in B[a]P treated group were significantly reduced as compared to naive and control. Subsequent observation showed that the area and perimeter of hippocampus, hippocampal neurons and neuronal nucleus were significantly reduced in B[a]P treated group as compared to naive and control. The findings of the present study suggest that the alteration in hippocampal cytomorphometry and neuronal population associated with impaired antioxidant signaling and mood in B[a]P treated group could be an outcome of neuromorphological alteration leading to pyknotic cell death or impaired differential migration of neurons during early postnatal brain development. PMID:26946409

  13. Wheat leaf lipids during heat stress: I. High day and night temperatures result in major lipid alterations.

    Science.gov (United States)

    Narayanan, Sruthi; Tamura, Pamela J; Roth, Mary R; Prasad, P V Vara; Welti, Ruth

    2016-04-01

    Understanding how wheat (Triticum aestivum L.) plants under high temperature (HT) regulate lipid composition is critical to developing climate-resilient varieties. We measured 165 glycerolipids and sterol derivatives under optimum and high day and night temperatures in wheat leaves using electrospray ionization-tandem mass spectrometry. Levels of polar lipid fatty acyl chain unsaturation were lower in both heat-tolerant genotype Ventnor and susceptible genotype Karl 92 under HT, compared with optimum temperature. The lower unsaturation was predominantly because of lower levels of 18:3 acyl chains and higher levels of 18:1 and 16:0 acyl chains. Levels of 18:3-containing triacylglycerols increased threefold/more under HT, consistent with their possible role in sequestering fatty acids during membrane lipid remodelling. Phospholipids containing odd-numbered or oxidized acyl chains accumulated in leaves under HT. Sterol glycosides (SG) and 16:0-acylated sterol glycosides (ASG) were higher under HT than optimum temperatures. Ventnor had lower amounts of phospholipids with oxidized acyl chains under HT and higher amounts of SG and 16:0-ASG than Karl 92. Taken together, the data demonstrate that wheat leaf lipid composition is altered by HT, in which some lipids are particularly responsive to HT, and that two wheat genotypes, chosen for their differing physiological responses to HT, differ in lipid profile under HT. PMID:26436679

  14. Oxidative stress in mouse sperm impairs embryo development, fetal growth and alters adiposity and glucose regulation in female offspring.

    Directory of Open Access Journals (Sweden)

    Michelle Lane

    Full Text Available Paternal health cues are able to program the health of the next generation however the mechanism for this transmission is unknown. Reactive oxygen species (ROS are increased in many paternal pathologies, some of which program offspring health, and are known to induce DNA damage and alter the methylation pattern of chromatin. We therefore investigated whether a chemically induced increase of ROS in sperm impairs embryo, pregnancy and offspring health. Mouse sperm was exposed to 1500 µM of hydrogen peroxide (H2O2, which induced oxidative damage, however did not affect sperm motility or the ability to bind and fertilize an oocyte. Sperm treated with H2O2 delayed on-time development of subsequent embryos, decreased the ratio of inner cell mass cells (ICM in the resulting blastocyst and reduced implantation rates. Crown-rump length at day 18 of gestation was also reduced in offspring produced by H2O2 treated sperm. Female offspring from H2O2 treated sperm were smaller, became glucose intolerant and accumulated increased levels of adipose tissue compared to control female offspring. Interestingly male offspring phenotype was less severe with increases in fat depots only seen at 4 weeks of age, which was restored to that of control offspring later in life, demonstrating sex-specific impacts on offspring. This study implicates elevated sperm ROS concentrations, which are common to many paternal health pathologies, as a mediator of programming offspring for metabolic syndrome and obesity.

  15. Performance of Surgical Stress Index during Sevoflurane-Fentanyl and Isoflurane-Fentanyl Anesthesia

    OpenAIRE

    Toivonen, J.; M. Kymäläinen; M. Huiku; Uutela, K; Parkkari, T.; Mustola, S.

    2010-01-01

    The performance of recently introduced Surgical Stress Index (SSI), based on heart rate and photoplethysmography, was estimated during sevoflurane-fentanyl and isoflurane-fentanyl anesthesia during surgical procedures. Forty ASA I–III patients were enrolled. Anesthesia was induced with fentanyl 2 μg kg−1 and thiopentone 3–5 mg kg−1. Tracheal intubation was performed 5 minutes after fentanyl bolus. Patients were randomly allocated to receive sevoflurane (n = 20) or isoflurane (n = 20) in 30% o...

  16. Maternal separation and early stress cause long-lasting effects on dopaminergic and endocannabinergic systems and alters dendritic morphology in the nucleus accumbens and frontal cortex in rats.

    Science.gov (United States)

    Romano-López, Antonio; Méndez-Díaz, Mónica; García, Fabio García; Regalado-Santiago, Citlalli; Ruiz-Contreras, Alejandra E; Prospéro-García, Oscar

    2016-08-01

    A considerable amount experimental studies have shown that maternal separation (MS) is associated with adult offspring abnormal behavior and cognition disorder. Accordingly, this experimental procedure has been proposed as a predictor for alcohol and drug dependence based on the neurodevelopmental soon after birth. Endocannabinoid system (eCBs) has been implicated in reward processes, including drug abuse and dependence. MS and associated stress causes changes in the eCBs that seem to facilitate alcohol consumption. In this study, we seek to evaluate potential morphological changes in neurons of the frontal cortex (FCx) and nucleus accumbens (NAcc), in the expression of receptors and enzymes of the endocannabinoid and dopamine systems and in second messengers, such as Akt, in adult rats subjected to MS and early stress (MS + ES; 2 × 180 min daily) vs. nonseparated rats (NMS). Results showed that MS + ES induces higher D2R expression and lower D3R, FAAH, and MAGL expression compared with NMS rats. Alterations in total dendritic length were also detected and were characterized by increases in the NAcc while there were decreases in the FCx. We believe MS + ES-induced changes in the dopaminergic and endocannabinergic systems and in the neuronal microstructure might be contributing to alcohol seeking behavior and, potential vulnerability to other drugs in rats. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 76: 819-831, 2016. PMID:26539755

  17. Leaf proteome alterations in the context of physiological and morphological responses to drought and heat stress in barley (Hordeum vulgare L.).

    Science.gov (United States)

    Rollins, J A; Habte, E; Templer, S E; Colby, T; Schmidt, J; von Korff, M

    2013-08-01

    The objective of this study was to identify barley leaf proteins differentially regulated in response to drought and heat and the combined stresses in context of the morphological and physiological changes that also occur. The Syrian landrace Arta and the Australian cultivar Keel were subjected to drought, high temperature, or a combination of both treatments starting at heading. Changes in the leaf proteome were identified using differential gel electrophoresis and mass spectrometry. The drought treatment caused strong reductions of biomass and yield, while photosynthetic performance and the proteome were not significantly changed. In contrast, the heat treatment and the combination of heat and drought reduced photosynthetic performance and caused changes of the leaf proteome. The proteomic analysis identified 99 protein spots differentially regulated in response to heat treatment, 14 of which were regulated in a genotype-specific manner. Differentially regulated proteins predominantly had functions in photosynthesis, but also in detoxification, energy metabolism, and protein biosynthesis. The analysis indicated that de novo protein biosynthesis, protein quality control mediated by chaperones and proteases, and the use of alternative energy resources, i.e. glycolysis, play important roles in adaptation to heat stress. In addition, genetic variation identified in the proteome, in plant growth and photosynthetic performance in response to drought and heat represent stress adaption mechanisms to be exploited in future crop breeding efforts. PMID:23918963

  18. Improvement of mood and sleep alterations in posttraumatic stress disorder patients by eye movement desensitization and reprocessing

    Directory of Open Access Journals (Sweden)

    Mara Regina Raboni

    2014-06-01

    Full Text Available Posttraumatic stress disorder (PTSD patients exhibit depressive and anxiety symptoms, in addition to nightmares, which interfere with sleep continuity. Pharmacologic treatment of these sleep problems improves PTSD symptoms, but very few studies have used psychotherapeutic interventions to treat PTSD and examined their effects on sleep quality. Therefore, in the present study, we sought to investigate the effects of Eye Movement Desensitization Reprocessing therapy on indices of mood, anxiety, subjective and objective sleep. The sample was composed of 11 healthy controls and 13 PTSD patients that were victims of assault and/or kidnapping. All participants were assessed before, and one day after, the end of treatment for depressive and anxiety profile, general well-being and subjective sleep by filling out specific questionnaires. In addition, objective sleep patterns were evaluated by polysomnographic recording. Healthy volunteers were submitted to the therapy for three weekly sessions, whereas PTSD patients underwent five sessions, on average. Before treatment, PTSD patients exhibited high levels of anxiety and depression, poor quality of life and poor sleep, assessed both subjectively and objectively; the latter was reflected by increased time of waking after sleep onset. After completion of treatment, patients exhibited improvement in depression and anxiety symptoms, and in quality of life; with indices that were no longer different from control volunteers. Moreover, these patients showed more consolidated sleep, with reduction of time spent awake after sleep onset. In conclusion, Eye Movement Desensitization and Reprocessing was an effective treatment of PTSD patients and improved the associated sleep and psychological symptoms.

  19. PEGylated Carbon Nanotubes Impair Retrieval of Contextual Fear Memory and Alter Oxidative Stress Parameters in the Rat Hippocampus

    Directory of Open Access Journals (Sweden)

    Lidiane Dal Bosco

    2015-01-01

    Full Text Available Carbon nanotubes (CNT are promising materials for biomedical applications, especially in the field of neuroscience; therefore, it is essential to evaluate the neurotoxicity of these nanomaterials. The present work assessed the effects of single-walled CNT functionalized with polyethylene glycol (SWCNT-PEG on the consolidation and retrieval of contextual fear memory in rats and on oxidative stress parameters in the hippocampus. SWCNT-PEG were dispersed in water at concentrations of 0.5, 1.0, and 2.1 mg/mL and infused into the rat hippocampus. The infusion was completed immediately after training and 30 min before testing of a contextual fear conditioning task, resulting in exposure times of 24 h and 30 min, respectively. The results showed that a short exposure to SWCNT-PEG impaired fear memory retrieval and caused lipid peroxidation in the hippocampus. This response was transient and overcome by the mobilization of antioxidant defenses at 24 h. These effects occurred at low and intermediate but not high concentration of SWCNT-PEG, suggesting that the observed biological response may be related to the concentration-dependent increase in particle size in SWCNT-PEG dispersions.

  20. Response of Arabidopsis thaliana Roots with Altered Lipid Transfer Protein (LTP) Gene Expression to the Clubroot Disease and Salt Stress.

    Science.gov (United States)

    Jülke, Sabine; Ludwig-Müller, Jutta

    2015-01-01

    The clubroot disease of Brassicaceae is caused by the obligate biotrophic protist Plasmodiophora brassicae. The disease is characterized by abnormal tumorous swellings of infected roots that result in reduced drought resistance and insufficient distribution of nutrients, leading to reduced crop yield. It is one of the most damaging diseases among cruciferous crops worldwide. The acquisition of nutrients by the protist is not well understood. Gene expression profiles in Arabidopsis thaliana clubroots indicate that lipid transfer proteins (LTPs) could be involved in disease development or at least in adaptation to the disease symptoms. Therefore, the aim of the study was to examine the role of some, of the still enigmatic LTPs during clubroot development. For a functional approach, we have generated transgenic plants that overexpress LTP genes in a root specific manner or show reduced LTP gene expression. Our results showed that overexpression of some of the LTP genes resulted in reduced disease severity whereas the lipid content in clubs of LTP mutants seems to be unaffected. Additional studies indicate a role for some LTPs during salt stress conditions in roots of A. thaliana. PMID:27135222

  1. Response of Arabidopsis thaliana Roots with Altered Lipid Transfer Protein (LTP Gene Expression to the Clubroot Disease and Salt Stress

    Directory of Open Access Journals (Sweden)

    Sabine Jülke

    2015-12-01

    Full Text Available The clubroot disease of Brassicaceae is caused by the obligate biotrophic protist Plasmodiophora brassicae. The disease is characterized by abnormal tumorous swellings of infected roots that result in reduced drought resistance and insufficient distribution of nutrients, leading to reduced crop yield. It is one of the most damaging diseases among cruciferous crops worldwide. The acquisition of nutrients by the protist is not well understood. Gene expression profiles in Arabidopsis thaliana clubroots indicate that lipid transfer proteins (LTPs could be involved in disease development or at least in adaptation to the disease symptoms. Therefore, the aim of the study was to examine the role of some, of the still enigmatic LTPs during clubroot development. For a functional approach, we have generated transgenic plants that overexpress LTP genes in a root specific manner or show reduced LTP gene expression. Our results showed that overexpression of some of the LTP genes resulted in reduced disease severity whereas the lipid content in clubs of LTP mutants seems to be unaffected. Additional studies indicate a role for some LTPs during salt stress conditions in roots of A. thaliana.

  2. Copper-induced growth inhibition, oxidative stress and ultrastructural alterations in freshly grown water lettuce (Pistia stratiotes L.).

    Science.gov (United States)

    Upadhyay, Rishi Kesh; Panda, Sanjib Kumar

    2009-07-01

    The effects of increasing concentrations of copper on the growth, ultra-structure and on certain biochemical parameters of water lettuce (Pistia stratiotes L.) were investigated under controlled conditions in the nutrient solutions containing increased copper sulfate concentrations ranging from 0 to 100 microM. Copper treatment for 12, 18 or 24 h resulted in inhibition of roots and leaves dry biomass. Atomic absorption spectrometry analysis of roots and leaves showed that copper accumulation increased with increase in concentration and duration of metal treatment. It is seen that copper resulted in increased production of hydrogen peroxide and superoxide radical in both roots and leave cells, showed a significant change after 24 h of treatment. Also, the significant decrease in the contents of total protein and photosynthetic pigments was observed. The antioxidant enzymes, viz., peroxidase (POX, E.C.1.11.1.7), catalase (CAT, E.C.1.11.1.6) and superoxide dismutase (SOD, E.C.1.15.1.1) showed significant variation with the increase in lipid peroxidation. Increasing trends was observed in levels of ascorbate and glutathione. The rapid inducibility of some of these enzymes are useful early and sensitive indicators of heavy metal toxicity. The results demonstrated that exposure to elevated concentration of Cu had a remarkable effect on the biochemistry and physiology, induced oxidative stress in water lettuce characterized by the initiation of lipid peroxidation that inhibited growth and disintegration of major antioxidant systems. PMID:19523602

  3. Grey matter alterations in post-traumatic stress disorder, obsessive–compulsive disorder and social anxiety disorder

    Directory of Open Access Journals (Sweden)

    Bochao eCheng

    2015-08-01

    Full Text Available Post-traumatic stress disorder (PTSD, obsessive-compulsive disorder (OCD and social anxiety disorder (SAD all bear the core symptom of anxiety and are separately classified in the new DSM-5 system. The aim of the present study is to obtain evidence for neuroanatomical difference for these disorders. We applied voxel-based morphometry (VBM with Diffeomorphic Anatomic Registration Through Exponentiated Lie (DARTEL to compare grey matter volume (GMV in Magnetic Resonance (MR images obtained for thirty patients with PTSD, twenty nine patients with OCD, twenty patients with SAD and thirty healthy controls. GMV across all four groups differed in left hypothalamus and left inferior parietal lobule and post hoc analyses revealed that this difference is primarily due to reduced GMV in the PTSD group relative to the other groups. Further analysis revealed that the PTSD group also showed reduced GMV in frontal lobe, temporal lobe and cerebellum compared to the OCD group, and reduced GMV in frontal lobes bilaterally compared to SAD group. A significant negative correlation with anxiety symptoms is observed for GMV in left hypothalamus in three disorder groups. We have thus found evidence for brain structure differences that in future could provide biomarkers to potentially support classification of these disorders using MRI.

  4. Improvement of mood and sleep alterations in posttraumatic stress disorder patients by eye movement desensitization and reprocessing.

    Science.gov (United States)

    Raboni, Mara R; Alonso, Fabiana F D; Tufik, Sergio; Suchecki, Deborah

    2014-01-01

    Posttraumatic stress disorder (PTSD) patients exhibit depressive and anxiety symptoms, in addition to nightmares, which interfere with sleep continuity. Pharmacologic treatment of these sleep problems improves PTSD symptoms, but very few studies have used psychotherapeutic interventions to treat PTSD and examined their effects on sleep quality. Therefore, in the present study, we sought to investigate the effects of Eye Movement Desensitization Reprocessing therapy on indices of mood, anxiety, subjective, and objective sleep. The sample was composed of 11 healthy controls and 13 PTSD patients that were victims of assault and/or kidnapping. All participants were assessed before, and 1 day after, the end of treatment for depressive and anxiety profile, general well-being and subjective sleep by filling out specific questionnaires. In addition, objective sleep patterns were evaluated by polysomnographic recording. Healthy volunteers were submitted to the therapy for three weekly sessions, whereas PTSD patients underwent five sessions, on average. Before treatment, PTSD patients exhibited high levels of anxiety and depression, poor quality of life and poor sleep, assessed both subjectively and objectively; the latter was reflected by increased time of waking after sleep onset. After completion of treatment, patients exhibited improvement in depression and anxiety symptoms, and in quality of life; with indices that were no longer different from control volunteers. Moreover, these patients showed more consolidated sleep, with reduction of time spent awake after sleep onset. In conclusion, Eye Movement Desensitization and Reprocessing was an effective treatment of PTSD patients and improved the associated sleep and psychological symptoms. PMID:24959123

  5. Survival, stress resistance, and alterations and protein expression in the marine Vibrio sp. strain S14 during starvation for different individual nutrients

    International Nuclear Information System (INIS)

    The response of the marine Vibrio sp. strain S14 to starvation for carbon, nitrogen, or phosphorus and to simultaneous depletion of all these nutrients (multiple-nutrient starvation) was examined with respect to survival, stress resistance, quantitative and qualitative alterations in protein and RNA synthesis, and the induction of the stringent control. Of the conditions tested, carbon starvation and multiple-nutrient starvation both promoted long-term starvation resistance and a rapid induction of the stringent control, as deduced from the kinetics of RNA synthesis. Carbon- and multiple-nutrient-starved cells were also found to become increasingly resistant to heat, UV, near-UV, and CdCl2 stress. Nitrogen- and phosphorus-starved cells demonstrated a poor ability to survive in the presence of carbon and did not develop a marked resistance to the stresses examined. The carbon, nitrogen, and phosphorus starvation stimulons consisted of about 20 proteins each, while simultaneous starvation for all the nutrients elicited an increased synthesis of 42 polypeptides. Nine common proteins were found to be induced regardless of the starvation condition used and were tentatively termed general starvation proteins. It was also demonstrated that the total number of proteins induced in response to multiple-nutrient starvation was not a predictable sum of the different individual starvation stimulons. Multiple-nutrient starvation induced 14 protons which were not detected at increased levels of expression in response to individual starvation conditions. Furthermore, four out of five phosphorus starvation-specific polypeptides were not induced during simultaneous starvation for phosphorus, nitrogen, and carbon

  6. Alterations in Glutathione Redox Metabolism, Oxidative Stress, and Mitochondrial Function in the Left Ventricle of Elderly Zucker Diabetic Fatty Rat Heart

    Directory of Open Access Journals (Sweden)

    Haider Raza

    2012-11-01

    Full Text Available The Zucker diabetic fatty (ZDF rat is a genetic model in which the homozygous (FA/FA male animals develop obesity and type 2 diabetes. Morbidity and mortality from cardiovascular complications, due to increased oxidative stress and inflammatory signals, are the hallmarks of type 2 diabetes. The precise molecular mechanism of contractile dysfunction and disease progression remains to be clarified. Therefore, we have investigated molecular and metabolic targets in male ZDF (30–34 weeks old rat heart compared to age matched Zucker lean (ZL controls. Hyperglycemia was confirmed by a 4-fold elevation in non-fasting blood glucose (478.43 ± 29.22 mg/dL in ZDF vs. 108.22 ± 2.52 mg/dL in ZL rats. An increase in reactive oxygen species production, lipid peroxidation and oxidative protein carbonylation was observed in ZDF rats. A significant increase in CYP4502E1 activity accompanied by increased protein expression was also observed in diabetic rat heart. Increased expression of other oxidative stress marker proteins, HO-1 and iNOS was also observed. GSH concentration and activities of GSH-dependent enzymes, glutathione S-transferase and GSH reductase, were, however, significantly increased in ZDF heart tissue suggesting a compensatory defense mechanism. The activities of mitochondrial respiratory enzymes, Complex I and Complex IV were significantly reduced in the heart ventricle of ZDF rats in comparison to ZL rats. Western blot analysis has also suggested a decreased expression of IκB-α and phosphorylated-JNK in diabetic heart tissue. Our results have suggested that mitochondrial dysfunction and increased oxidative stress in ZDF rats might be associated, at least in part, with altered NF-κB/JNK dependent redox cell signaling. These results might have implications in the elucidation of the mechanism of disease progression and designing strategies for diabetes prevention.

  7. C9orf72 Hexanucleotide Expansions Are Associated with Altered Endoplasmic Reticulum Calcium Homeostasis and Stress Granule Formation in Induced Pluripotent Stem Cell‐Derived Neurons from Patients with Amyotrophic Lateral Sclerosis and Frontotemporal Dementia

    Science.gov (United States)

    Dafinca, Ruxandra; Scaber, Jakub; Ababneh, Nida'a; Lalic, Tatjana; Weir, Gregory; Christian, Helen; Vowles, Jane; Douglas, Andrew G.L.; Fletcher‐Jones, Alexandra; Browne, Cathy; Nakanishi, Mahito; Turner, Martin R.; Wade‐Martins, Richard

    2016-01-01

    Abstract An expanded hexanucleotide repeat in a noncoding region of the C9orf72 gene is a major cause of amyotrophic lateral sclerosis (ALS), accounting for up to 40% of familial cases and 7% of sporadic ALS in European populations. We have generated induced pluripotent stem cells (iPSCs) from fibroblasts of patients carrying C9orf72 hexanucleotide expansions, differentiated these to functional motor and cortical neurons, and performed an extensive phenotypic characterization. In C9orf72 iPSC‐derived motor neurons, decreased cell survival is correlated with dysfunction in Ca2+ homeostasis, reduced levels of the antiapoptotic protein Bcl‐2, increased endoplasmic reticulum (ER) stress, and reduced mitochondrial membrane potential. Furthermore, C9orf72 motor neurons, and also cortical neurons, show evidence of abnormal protein aggregation and stress granule formation. This study is an extensive characterization of iPSC‐derived motor neurons as cellular models of ALS carrying C9orf72 hexanucleotide repeats, which describes a novel pathogenic link between C9orf72 mutations, dysregulation of calcium signaling, and altered proteostasis and provides a potential pharmacological target for the treatment of ALS and the related neurodegenerative disease frontotemporal dementia. Stem Cells 2016;34:2063–2078 PMID:27097283

  8. Mechanisms of oxidative stress and alterations in gene expression by Libby six-mix in human mesothelial cells

    Directory of Open Access Journals (Sweden)

    Hillegass Jedd M

    2010-09-01

    Full Text Available Abstract Background Exposures to an amphibole fiber in Libby, Montana cause increases in malignant mesothelioma (MM, a tumor of the pleural and peritoneal cavities with a poor prognosis. Affymetrix microarray/GeneSifter analysis was used to determine alterations in gene expression of a human mesothelial cell line (LP9/TERT-1 by a non-toxic concentration (15×106 μm2/cm2 of unprocessed Libby six-mix and negative (glass beads and positive (crocidolite asbestos controls. Because manganese superoxide dismutase (MnSOD; SOD2 was the only gene upregulated significantly (p 6 μm2/cm2 and toxic concentrations (75×106 μm2/cm2 of Libby six-mix. Results Exposure to 15×106 μm2/cm2 Libby six-mix elicited significant (p SOD2; 4-fold at 8 h and 111 gene changes at 24 h, including a 5-fold increase in SOD2. Increased levels of SOD2 mRNA at 24 h were also confirmed in HKNM-2 normal human pleural mesothelial cells by qRT-PCR. SOD2 protein levels were increased at toxic concentrations (75×106 μm2/cm2 of Libby six-mix at 24 h. In addition, levels of copper-zinc superoxide dismutase (Cu/ZnSOD; SOD1 protein were increased at 24 h in all mineral groups. A dose-related increase in SOD2 activity was observed, although total SOD activity remained unchanged. Dichlorodihydrofluorescein diacetate (DCFDA fluorescence staining and flow cytometry revealed a dose- and time-dependent increase in reactive oxygen species (ROS production by LP9/TERT-1 cells exposed to Libby six-mix. Both Libby six-mix and crocidolite asbestos at 75×106 μm2/cm2 caused transient decreases (p HO-1 in LP9/TERT-1 and HKNM-2 cells. Conclusions Libby six-mix causes multiple gene expression changes in LP9/TERT-1 human mesothelial cells, as well as increases in SOD2, increased production of oxidants, and transient decreases in intracellular GSH. These events are not observed at equal surface area concentrations of nontoxic glass beads. Results support a mechanistic basis for the importance of SOD2

  9. EFFECT OF STRESS AND PSYCHOLOGICAL OVERLOAD AT WORK ON PERFORMANCE OF EMPLOYEES

    Directory of Open Access Journals (Sweden)

    MAREK ŠOLC

    2009-12-01

    Full Text Available The workload represents a factor which acts burdensome on human organism and, depending on its level affects well-being, or leads to disease or injury. As a result, there is a distortion in optimal working relationship in the system man – machine – environment, which may be reflected in the reduction of productivity and efficiency throughout the system. The contribution deals with the issue of the effects of stress and psychological overload at work, which affects significantly the performance of employees. The article describes the basic legislation regarding the workload in conditions of the Slovak Republic, it describes the types of loads, different causes, manifestations and consequences of load. According to theoretical knowledge about stress and loads, the questionnaire method was applied for assessment of mental workload in terms of working conditions level in the unnamed service organization.

  10. Altered Anxiety-like Behavior and Long-term Potentiation in the Bed Nucleus of the Stria Terminalis in Adult Mice Exposed to Chronic Social Isolation, Unpredictable Stress and Ethanol Beginning in Adolescence

    OpenAIRE

    Conrad, Kelly L; Winder, Danny G.

    2010-01-01

    Alcohol and chronic stress exposure, especially during adolescence, can lead to an increased risk in adulthood of developing alcohol use disorders (AUDs). To date, however, no study has assessed the potential long-term effects of chronic intermittent and unpredictable ethanol (EtOH) exposure in mice chronically stressed beginning in adolescence on brain function and anxiety-like behaviors in adulthood. In particular, alterations in function of the bed nucleus of the stria terminalis (BNST), a...

  11. Stress, Cognition, and Human Performance: A Literature Review and Conceptual Framework

    Science.gov (United States)

    Staal, Mark A.

    2004-01-01

    The following literature review addresses the effects of various stressors on cognition. While attempting to be as inclusive as possible, the review focuses its examination on the relationships between cognitive appraisal, attention, memory, and stress as they relate to information processing and human performance. The review begins with an overview of constructs and theoretical perspectives followed by an examination of effects across attention, memory, perceptual-motor functions, judgment and decision making, putative stressors such as workload, thermals, noise, and fatigue and closes with a discussion of moderating variables and related topics. In summation of the review, a conceptual framework for cognitive process under stress has been assembled. As one might imagine, the research literature that addresses stress, theories governing its effects on human performance, and experimental evidence that supports these notions is large and diverse. In attempting to organize and synthesize this body of work, I was guided by several earlier efforts (Bourne & Yaroush, 2003; Driskell, Mullen, Johnson, Hughes, & Batchelor, 1992; Driskell & Salas, 1996; Haridcock & Desmond, 2001; Stokes & Kite, 1994). These authors should be credited with accomplishing the monumental task of providing focused reviews in this area and their collective efforts laid the foundation for this present review. Similarly, the format of this review has been designed in accordance with these previous exemplars. However, each of these previous efforts either simply reported general findings, without sufficient experimental illustration, or narrowed their scope of investigation to the extent that the breadth of such findings remained hidden from the reader. Moreover, none of these examinations yielded an architecture that adequately describes or explains the inter-relations between information processing elements under stress conditions.

  12. The Influence of the ‘Trier Social Stress Test’ on Free Throw Performance in Basketball: An Interdisciplinary Study

    OpenAIRE

    Mascret, Nicolas; Ibáñez-Gijón, Jorge; Bréjard, Vincent; Buekers, Mart; Casanova, Rémy; Marqueste, Tanguy; Montagne, Gilles; Rao, Guillaume; Roux, Yannick; CURY, François

    2016-01-01

    The aim of the present study was to explore the relationship between stress and sport performance in a controlled setting. The experimental protocol used to induce stress in a basketball free throw was the Trier Social Stress Test (TSST) and its control condition (Pla- cebo-TSST). Participants (n = 19), novice basketball players but trained sportspersons, were exposed to two counterbalanced conditions in a crossover design. They were equipped with sensors to measure movement execution, whi...

  13. Chronic dietary mercury exposure causes oxidative stress, brain lesions, and altered behaviour in Atlantic salmon (Salmo salar) parr

    Energy Technology Data Exchange (ETDEWEB)

    Berntssen, Marc H.G.; Aatland, Aase; Handy, Richard D

    2003-10-08

    Atlantic salmon (Salmo salar L.) parr were fed for 4 months on fish meal based diets supplemented with mercuric chloride (0, 10, or 100 mg Hg kg{sup -1} DW) or methylmercury chloride (0, 5, or 10 mg Hg kg{sup -1} DW) to assess the effects of inorganic (Hg) and organic dietary mercury on brain lipid peroxidation and neurotoxicity. Lipid peroxidative products, endogenous anti oxidant enzymes, brain histopathology, and overall behaviour were measured. Methylmercury accumulated significantly in the brain of fish fed 5 or 10 mg kg{sup -1} by the end of the experiment, and inorganic mercury accumulated significantly in the brain only at 100 mg kg{sup -1} exposure levels. No mortality or growth reduction was observed in any of the exposure groups. Fish fed 5 mg kg{sup -1} methylmercury had a significant increase (2-fold) in the antioxidant enzyme super oxide dismutase (SOD) in the brain. At dietary levels of 10 mg kg{sup -1} methylmercury, a significant increase (7-fold) was observed in lipid peroxidative products (thiobarbituric acid reactive substances, TBARS) and a subsequently decrease (1.5-fold) in anti oxidant enzyme activity (SOD and glutathione peroxidase, GSH-Px). Fish fed 10 mg kg{sup -1} methylmercury also had pathological damage (vacoulation and necrosis), significantly reduced neural enzyme activity (5-fold reduced monoamine oxidase, MAO, activity), and reduced overall post-feeding activity behaviour. Pathological injury started in the brain stem and became more widespread in other areas of the brain at higher exposure levels. Fish fed 100 mg Hg kg{sup -1} inorganic mercury had significant reduced neural MAO activity and pathological changes (astrocyte proliferation) in the brain, however, neural SOD and GSH-Px enzyme activity, lipid peroxidative products (TBARS), and post feeding behaviour did not differ from controls. Compared with other organs, the brain is particular susceptible for dietary methylmercury induced lipid peroxidative stress at relative low

  14. Environmental conditions experienced during the tadpole stage alter post-metamorphic glucocorticoid response to stress in an amphibian.

    Science.gov (United States)

    Crespi, Erica J; Warne, Robin W

    2013-12-01

    Exposure to adverse environmental conditions during early development can shape life-history traits and have lasting effects on physiological function in later life. Although findings within the biomedical literature have shown that environmentally induced elevations in glucocorticoids (GCs) during critical developmental windows can cause persistent carry-over effects (i.e., developmental programming), little is known about whether such effects of GCs can be generalized to wildlife species. Using wood frogs as a study species, we conducted an experiment with a split-plot design to assess the short-term and the long-term physiological consequences of availability of food, hydroperiod length (i.e., pond drying), and the interaction between these two environmental conditions. In outdoor experimental ponds, we reared tadpoles in chronically high or low-food conditions, and tadpoles from each pond experienced either high water until metamorphosis or a reduction in water volume during late developmental stages (after Gosner stage 38). After metamorphosis, animals were housed individually and fed ad libitum for 10 weeks, and growth rate, fat content, and resting and acute stress-induced GC levels were measured. We found that tadpoles experiencing low availability of food and reduced water volume had elevated GC levels, reduced mass, and body condition as they approached metamorphosis. At 10 weeks after metamorphosis, we found that these two conditions also had persistent interactive effects on post-metamorphic allocation of resources to growth, energy storage, and responsiveness of GCs to a novel stressor. Of individuals that experienced reduced water volume, only those that experienced high food as tadpoles were able to catch up to individuals that did not experience reduced water volume in terms of body mass, femur length, and body condition, and they allocated more resources to fat storage. By contrast, 10-week old frogs with low-food and that experienced low water

  15. Neuro-functional and neuro-endocrine alterations in a cohort of patients attending with post traumatic stress disorder

    International Nuclear Information System (INIS)

    Post Traumatic Stress Disorder (PTSD) is one of the most important emergent pathologies in mental health and is usually associated with current post modern's life styles and with specific traumatic event such as belic conflicts or incident involving criminal behaviors affecting civilians. It is well known that 8% of victims of a traumatic event will develop PTSD. Furthermore, the chronicity and social impairment associated to this clinical entity requires an enormous effort from mental health's professionals and huge costs to the systems involved in the rehabilitation of these patients. The aim of this study is to evaluate a sample of 7 patients affected from PTSD in order to understand their clinical characteristics, neuro-functional features and possible neuro-endocrine abnormatilies. Method: 7 patient affected with PTSD were clinically evaluated and submitted to a specific-validated post traumatic scale (Davidson scale) and also to a depression inventory (Beck depression inventory). Then, blood samples were taken in order to assess. Neuro- endocrine levels of cortisol in plasma and T3, T4 and TSH levels. Finally, the subjects were studied by means of SPECT, delineating specific Region of Interest (ROI) involved in the neurobiological basis of PTSD. Results: we report on, for the entire sample, high scores on both scales used (Davidson scale: 91.85; Beck inventory: 25.28). These results confirm the previously reported high comorbidity between this two clinical entities. We describe average normal values for plasmatic cortisol levels and thyroid hormones levels T3, T4, TSH (17.35 ug/dl, 1.34 ng/ml, 6.98 ug/dl and 2.95 uUI/ml respectively). It is important to remark the presence of Hypercortisolemia in 3 of the patients studied. Neuro-functional features were characterized by a cortical fronto-parietal hyper-perfusion and hypo-perfusion on limbic areas. This results were consistently replicated in the entire sample. We hypothesized a blood-brain barrier dysfunction

  16. Early-Life Adversity Interacts with FKBP5 Genotypes: Altered Working Memory and Cardiac Stress Reactivity in the Oklahoma Family Health Patterns Project.

    Science.gov (United States)

    Lovallo, William R; Enoch, Mary-Anne; Acheson, Ashley; Cohoon, Andrew J; Sorocco, Kristen H; Hodgkinson, Colin A; Vincent, Andrea S; Goldman, David

    2016-06-01

    Exposure to stress during critical periods of development can have adverse effects on adult health behaviors, and genetic vulnerabilities may enhance these stress effects. We carried out an exploratory examination of psychological, physiological, and behavioral characteristics of 252 healthy young adults for the impact of early-life adversity (ELA) in relation to the G-to-A single nucleotide polymorphism (SNP), rs9296158, of the FKBP5 gene. FKBP5 is a molecular cochaperone that contributes to the functional status of the glucocorticoid receptor (GR) and to the quality of corticosteroid signaling. FKBP5 expression is upregulated by cortisol exposure during stressful episodes, with greater upregulation seen in A-allele carriers. As such, FKBP5 expression and GR function may be environmentally sensitive in A-allele carriers and therefore suitable for the study of gene-by-environment (G × E) interactions. Compared with FKBP5, GG homozygotes (N=118), A-allele carriers (N = 132) without psychiatric morbidity had progressively worse performance on the Stroop color-word task with increasing levels of ELA exposure (Genotype × ELA, F=5.14, P=0.007), indicating a G × E interaction on working memory in early adulthood. In addition, heart rate response to mental stress was diminished overall in AA/AG-allele carriers (F=5.15, P=0.024). Diminished working memory and attenuated autonomic responses to stress are both associated with risk for alcoholism and other substance use disorders. The present data suggest that FKBP5 in the GR pathway may be a point of vulnerability to ELA, as seen in this group of non-traumatized young adults. FKBP5 is accordingly a potential target for more extensive studies of the impact of ELA on health and health behaviors in adulthood. PMID:26632991

  17. Coping with stress and cognitive interference in student teachers performance as important factors influencing their achievement

    Directory of Open Access Journals (Sweden)

    Cirila Peklaj

    2001-06-01

    Full Text Available The purpose of our study was to investigate the relations between student teachers' strategies for coping with stressful situations, cognitive interference factors and successfulness of presentation of student teachers' seminar work. There were 135 student teachers participating in the study. At the beginning of the semester they filled in the Way of Coping Questionnaire (Folkman & Lazarus, 1988. After their presentation of seminar theme they reported about the cognitive interference factors during the presentation (distractive factors and intrusive thoughts. Different aspects of their performance were also evaluated by the teacher according to the well-known criteria. The analysis of the results showed significant correlations between certain ways of coping, cognitive interference factors and success of performance. Further statistical analysis showed significant differences in experiencing distractive factors and intrusive thoughts during presentation between students with low, medium and high performance success. The importance of successful strategies for coping with verbal presentation and the implications for student teacher education are discussed.

  18. Effects of stress upon psychophysiological responses and performance following sleep deprivation

    Science.gov (United States)

    Roessler, R.; Lester, J. W.

    1972-01-01

    The usefulness of psychological and physiological variables in predicting performance under stress of 48 hours of sleep deprivation was investigated. Performance tests, with subjects of different ego strength personalities, in concept acquisition, reading comprehension, word association, word memory, and anagrams were conducted, and physiological measurements of (1) the phasic and tonic electrodermal, (2) galvanic skin response, (3) thermal skin resistance, (4) heart rate, (5) respiration, and (6) plethysmographic finger pulse volumn were recorded. It was found that the changes in the pattern of performance were the result of testing subjects at times when they would normally be sleeping, and that sleep deprivation longer than 48 hours must be maintained to produce changes in simple or well learned tasks.

  19. Water stress and recovery in the performance of two Eucalyptus globulus clones: physiological and biochemical profiles.

    Science.gov (United States)

    Correia, Barbara; Pintó-Marijuan, Marta; Neves, Lucinda; Brossa, Ricard; Dias, Maria Celeste; Costa, Armando; Castro, Bruno B; Araújo, Clara; Santos, Conceição; Chaves, Maria Manuela; Pinto, Glória

    2014-04-01

    Eucalyptus plantations are among the most productive forest stands in Portugal and Spain, being mostly used for pulp production and, more recently, as an energy crop. However, the region's Mediterranean climate, with characteristic severe summer drought, negatively affects eucalypt growth and increases mortality. Although the physiological response to water shortage is well characterized for this species, evidence about the plants' recovery ability remains scarce. In order to assess the physiological and biochemical response of Eucalyptus globulus during the recovery phase, two genotypes (AL-18 and AL-10) were submitted to a 3-week water stress period at two different intensities (18 and 25% of field capacity), followed by 1 week of rewatering. Recovery was assessed 1 day and 1 week after rehydration. Drought reduced height, biomass, water potential, NPQ and gas exchange in both genotypes. Contrarily, the levels of pigments, chlorophyll fluorescence parameters (F(v) /F(m) and (φPSII)), MDA and ABA increased. During recovery, the physiological and biochemical profile of stressed plants showed a similar trend: they experienced reversion of altered traits (MDA, ABA, E, g(s), pigments), while other parameters did not recover ((φPSII), NPQ). Furthermore, an overcompensation of CO(2) assimilation was achieved 1 week after rehydration, which was accompanied by greater growth and re-establishment of oxidative balance. Both genotypes were tolerant to the tested conditions, although clonal differences were found. AL-10 was more productive and showed a more rapid and dynamic response to rehydration (namely in carotenoid content, (φPSII) and NPQ) compared to clone AL-18. PMID:24117924

  20. Rising to the Challenge: Acute Stress Appraisals and Selection Centre Performance in Applicants to Postgraduate Specialty Training in Anaesthesia

    Science.gov (United States)

    Roberts, Martin J.; Gale, Thomas C. E.; McGrath, John S.; Wilson, Mark R.

    2016-01-01

    The ability to work under pressure is a vital non-technical skill for doctors working in acute medical specialties. Individuals who evaluate potentially stressful situations as challenging rather than threatening may perform better under pressure and be more resilient to stress and burnout. Training programme recruitment processes provide an…