Sample records for acute temperature stress

  1. Skin temperature reveals the intensity of acute stress

    PubMed Central

    Herborn, Katherine A.; Graves, James L.; Jerem, Paul; Evans, Neil P.; Nager, Ruedi; McCafferty, Dominic J.; McKeegan, Dorothy E.F.

    2015-01-01

    Acute stress triggers peripheral vasoconstriction, causing a rapid, short-term drop in skin temperature in homeotherms. We tested, for the first time, whether this response has the potential to quantify stress, by exhibiting proportionality with stressor intensity. We used established behavioural and hormonal markers: activity level and corticosterone level, to validate a mild and more severe form of an acute restraint stressor in hens (Gallus gallus domesticus). We then used infrared thermography (IRT) to non-invasively collect continuous temperature measurements following exposure to these two intensities of acute handling stress. In the comb and wattle, two skin regions with a known thermoregulatory role, stressor intensity predicted the extent of initial skin cooling, and also the occurrence of a more delayed skin warming, providing two opportunities to quantify stress. With the present, cost-effective availability of IRT technology, this non-invasive and continuous method of stress assessment in unrestrained animals has the potential to become common practice in pure and applied research. PMID:26434785

  2. Skin temperature reveals the intensity of acute stress.

    PubMed

    Herborn, Katherine A; Graves, James L; Jerem, Paul; Evans, Neil P; Nager, Ruedi; McCafferty, Dominic J; McKeegan, Dorothy E F

    2015-12-01

    Acute stress triggers peripheral vasoconstriction, causing a rapid, short-term drop in skin temperature in homeotherms. We tested, for the first time, whether this response has the potential to quantify stress, by exhibiting proportionality with stressor intensity. We used established behavioural and hormonal markers: activity level and corticosterone level, to validate a mild and more severe form of an acute restraint stressor in hens (Gallus gallus domesticus). We then used infrared thermography (IRT) to non-invasively collect continuous temperature measurements following exposure to these two intensities of acute handling stress. In the comb and wattle, two skin regions with a known thermoregulatory role, stressor intensity predicted the extent of initial skin cooling, and also the occurrence of a more delayed skin warming, providing two opportunities to quantify stress. With the present, cost-effective availability of IRT technology, this non-invasive and continuous method of stress assessment in unrestrained animals has the potential to become common practice in pure and applied research. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Hypnotizability in acute stress disorder.

    PubMed

    Bryant, R A; Guthrie, R M; Moulds, M L

    2001-04-01

    This study investigated the relationship between acute dissociative reactions to trauma and hypnotizability. Acutely traumatized patients (N=61) with acute stress disorder, subclinical acute stress disorder (no dissociative symptoms), and no acute stress disorder were administered the Stanford Hypnotic Clinical Scale within 4 weeks of their trauma. Although patients with acute stress disorder and patients with subclinical acute stress disorder displayed comparable levels of nondissociative psychopathology, acute stress disorder patients had higher levels of hypnotizability and were more likely to display reversible posthypnotic amnesia than both patients with subclinical acute stress disorder and patients with no acute stress disorder. The findings may be interpreted in light of a diathesis-stress process mediating trauma-related dissociation. People who develop acute stress disorder in response to traumatic experience may have a stronger ability to experience dissociative phenomena than people who develop subclinical acute stress disorder or no acute stress disorder.

  4. Association between temperature and maternal stress during pregnancy.

    PubMed

    Lin, Yanfen; Hu, Wenjing; Xu, Jian; Luo, Zhongcheng; Ye, Xiaofang; Yan, Chonghuai; Liu, Zhiwei; Tong, Shilu

    2017-10-01

    Maternal psychological stress during pregnancy has essentially been conceptualized as a teratogen. However, little is known about the effect of temperature on maternal stress during pregnancy. The aim of this study is to investigate the relationship between temperature and maternal stress during pregnancy. In 2010, a total of 1931 eligible pregnant women were enrolled across Shanghai from four prenatal-care clinics during their mid-to-late pregnancy. Maternal life-event stress and emotional stress levels during pregnancy were assessed by the "Life Event Scale for Pregnant Women" (LESPW) and "Symptom Checklist-90-Revised Scale" (SCL-90-R), respectively. Exposure to ambient temperature was evaluated based on daily regional average in different moving average and lag days. The generalized estimating equations were used to evaluate the relationship between daily average temperature/temperature difference and maternal stress. After adjusting for relevant confounders, an U-shaped relationship was observed between daily average temperature and maternal Global-Severity-Index (GSI) of the SCL-90-R. Cumulative exposures to extremely low temperatures (< P5, 1.4-10.5℃, lag 0-1 days, 0-2 days and 0-5 days) and extremely high temperatures (≥ P95, 31.2-34.1℃, lag 0-1 days and 0-2 days), and acute exposures to extremely low (lag day 0, 1, 2 and 3) and high (lag day 0, 1) temperatures, all induced higher risks of high GSI (the highest tertile), compared to the risk induced by exposed to an optimal temperature range (20-25℃) (P< 0.05). Increased temperature difference was associated with high maternal GSI (P< 0.05). However, non-significant associations were observed between daily average temperatures/temperature differences and maternal log-transferred LESPW scores. Cumulative and acute exposures to extremely low/high temperatures may both induce emotional stress during pregnancy. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Dissociating anxiolytic and sedative effects of GABAAergic drugs using temperature and locomotor responses to acute stress

    PubMed Central

    Klanker, Marianne; Groenink, Lucianne; Korte, S. Mechiel; Cook, James M.; Van Linn, Michael L.; Hopkins, Seth C.; Olivier, Berend

    2009-01-01

    Rationale The stress-induced hyperthermia (SIH) model is an anxiety model that uses the transient rise in body temperature in response to acute stress. Benzodiazepines produce anxiolytic as well as sedative side effects through nonselective binding to GABAA receptor subunits. The GABAA receptor α1 subunit is associated with sedation, whereas the GABAA receptor α2 and α3 subunits are involved in anxiolytic effects. Objectives We therefore examined the effects of (non) subunit-selective GABAA receptor agonists on temperature and locomotor responses to novel cage stress. Results Using telemetric monitoring of temperature and locomotor activity, we found that nonsubunit-selective GABAA receptor agonist diazepam as well as the α3 subunit-selective receptor agonist TP003 dose-dependently attenuated SIH and locomotor responses. Administration of GABAA receptor α1-selective agonist zolpidem resulted in profound hypothermia and locomotor sedation. The GABAA receptor α1-selective antagonist βCCt antagonized the hypothermia, but did not reverse the SIH response attenuation caused by diazepam and zolpidem. These results suggest an important regulating role for the α1 subunit in thermoregulation and sedation. Ligands of extrasynaptic GABAA receptors such as alcohol and nonbenzodiazepine THIP attenuated the SIH response only at high doses. Conclusions The present study confirms a putative role for the GABAA receptor α1 subunit in hypothermia and sedation and supports a role for α2/3 subunit GABAA receptor agonists in anxiety processes. In conclusion, we show that home cage temperature and locomotor responses to novel home cage stress provide an excellent tool to assess both anxiolytic and sedative effects of various (subunit-selective) GABAAergic compounds. PMID:19169673

  6. Deep Transcriptomic Analysis of Black Rockfish (Sebastes schlegelii) Provides New Insights on Responses to Acute Temperature Stress.

    PubMed

    Lyu, Likang; Wen, Haishen; Li, Yun; Li, Jifang; Zhao, Ji; Zhang, Simin; Song, Min; Wang, Xiaojie

    2018-06-14

    In the present study, we conducted an RNA-Seq analysis to characterize the genes and pathways involved in acute thermal and cold stress responses in the liver of black rockfish, a viviparous teleost that has the ability to cope with a wide range of temperature changes. A total of 584 annotated differentially expressed genes (DEGs) were identified in all three comparisons (HT vs NT, HT vs LT and LT vs NT). Based on an enrichment analysis, DEGs with a potential role in stress accommodation were classified into several categories, including protein folding, metabolism, immune response, signal transduction, molecule transport, membrane, and cell proliferation/apoptosis. Considering that thermal stress has a greater effect than cold stress in black rockfish, 24 shared DEGs in the intersection of the HT vs LT and HT vs NT groups were enriched in 2 oxidation-related gene ontology (GO) terms. Nine important heat-stress-reducing pathways were significantly identified and classified into 3 classes: immune and infectious diseases, organismal immune system and endocrine system. Eight DEGs (early growth response protein 1, bile salt export pump, abcb11, hsp70a, rtp3, 1,25-dihydroxyvitamin d(3) 24-hydroxylase, apoa4, transcription factor jun-b-like and an uncharacterized gene) were observed among all three comparisons, strongly implying their potentially important roles in temperature stress responses.

  7. Juvenile stress impairs body temperature regulation and augments anticipatory stress-induced hyperthermia responses in rats.

    PubMed

    Yee, Nicole; Plassmann, Kerstin; Fuchs, Eberhard

    2011-09-01

    Clinical studies have implicated adolescence as an important and vulnerable period during which traumatic experiences can predispose individuals to anxiety and mood disorders. As such, a stress model in juvenile rats (age 27-29 d) was previously developed to investigate the long-term effects of stress exposure during adolescence on behavior and physiology. This paradigm involves exposing rats to different stressors on consecutive days over a 3-day period. Here, we studied the effects of juvenile stress on long-term core body temperature regulation and acute stress-induced hyperthermia (SIH) responses using telemetry. We found no differences between control and juvenile stress rats in anxiety-related behavior on the elevated plus maze, which we attribute to stress associated with surgical implantation of telemetry devices. This highlights the severe impact of surgical stress on the results of subsequent behavioral measurements. Nonetheless, juvenile stress disrupted the circadian rhythmicity of body temperature and decreased circadian amplitude. It also induced chronic hypothermia during the dark phase of the day, when rats are most active. When subjected to acute social defeat stress as adults, juvenile stress had no impact on the SIH response relative to controls. However, 24 h later, juvenile stress rats displayed an elevated SIH response in anticipation of social defeat when re-exposed to the social defeat environment. Taken together, our findings indicate that juvenile stress can induce long-term alterations in body temperature regulation and heighten the increase in temperature associated with anticipation of social defeat. The outcomes of behavioral measurements in these experiments, however, are severely affected by surgical stress. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Young Children's Acute Stress After a Burn Injury: Disentangling the Role of Injury Severity and Parental Acute Stress.

    PubMed

    Haag, Ann-Christin; Landolt, Markus A

    2017-09-01

    Although injury severity and parental stress are strong predictors of posttraumatic adjustment in young children after burns, little is known about the interplay of these variables. This study aimed at clarifying mediation processes between injury severity and mother's, father's, and young child's acute stress. Structural equation modeling was used to examine the relationships between injury severity and parental and child acute stress. Parents of 138 burn-injured children (ages 1-4 years) completed standardized questionnaires on average 19 days postinjury. Sixteen children (11.7%) met Diagnostic and Statistical Manual of Mental Disorders, 5th edition, preschool criteria for posttraumatic stress disorder (excluding time criterion). The model revealed a significant mediation of maternal acute stress, with the effect of injury severity on a child's acute stress mediated by maternal acute stress. Paternal acute stress failed to serve as a mediating variable. Our findings confirm mothers' crucial role in the posttraumatic adjustment of young children. Clinically, mothers' acute stress should be monitored. © The Author 2017. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com

  9. Effects of acute changes in salinity and temperature on routine metabolism and nitrogen excretion in gambusia (Gambusia affinis) and zebrafish (Danio rerio).

    PubMed

    Uliano, E; Cataldi, M; Carella, F; Migliaccio, O; Iaccarino, D; Agnisola, C

    2010-11-01

    Acute stress may affect metabolism and nitrogen excretion as part of the adaptive response that allows animals to face adverse environmental changes. In the present paper the acute effects of different salinities and temperatures on routine metabolism, spontaneous activity and excretion of ammonia and urea were studied in two freshwater fish: gambusia, Gambusia affinis and zebrafish, Danio rerio, acclimated to 27 degrees C. The effects on gill morphology were also evaluated. Five salinities (0 per thousand, 10 per thousand, 20 per thousand, 30 per thousand and 35 per thousand) were tested in gambusia, while four salinities were used in zebrafish (0 per thousand, 10 per thousand, 20 per thousand and 25 per thousand). Each salinity acute stress was tested alone or in combination with an acute temperature reduction to 20 degrees C. In gambusia, both salinity and temperature acute stress strongly stimulated urea excretion. Routine oxygen consumption was barely affected by acute salinity or temperature stress, and was reduced by the combined effects of temperature and high salinity. Gills maintained their structural integrity in all stressing conditions; hyperplasia and hypertrophy of mitochondria-rich cells were observed. In zebrafish, temperature and salinity acute changes, both alone and in combination, scarcely affected any parameter tested. The major effect observed was a reduction of nitrogen excretion at 20 degrees C-25 per thousand; under these extreme conditions a significant structural disruption of gills was observed. These results confirm the high tolerance to acute salinity and temperature stress in gambusia, and demonstrate the involvement of urea excretion modulation in the stress response in this species. Copyright 2010 Elsevier Inc. All rights reserved.

  10. Acute stress reactions after submarine accidents.

    PubMed

    Eid, Jarle; Johnsen, Bjørn Helge

    2002-05-01

    The aim of the present study was to explore contextual and individual factors associated with acute stress reactions in three Norwegian submarine crews exposed to different significant peacetime maneuver accidents. Approximately 2 to 3 weeks after the accidents, crew members completed the Coping Style Questionnaire, the General Health Questionnaire, the Impact of Event Scale, and the Post-Traumatic Symptom Scale. Although exposed subjects (N = 47) revealed more posttraumatic stress symptoms than nonexposed crew members on shore leave (N = 7), they showed less acute stress reactions than survivors from a surface ship accident in the Norwegian Navy. Inspection of individual cases revealed that 4% of the exposed submariners showed high loads of acute stress symptoms. Unit cohesion and habitual coping styles emerged as resilience factors, whereas previous exposure to critical incidents and personal experience of not coping in the accident situation emerged as vulnerability factors, explaining 32% of the acute stress reactions reported by submarine crew members.

  11. Acute cold stress improved the transcription of pro-inflammatory cytokines of Chinese soft-shelled turtle against Aeromonas hydrophila.

    PubMed

    Zhang, Zuobing; Chen, Bojian; Yuan, Lin; Niu, Cuijuan

    2015-03-01

    Chinese soft-shelled turtle, Pelodiscus sinensis, is widely cultured in East and Southeast Asian countries. It frequently encounters the stress of abrupt temperature changes, which leads to mass death in most cases. However, the mechanism underlying the stress-elicited death remains unknown. We have suspected that the stress impaired the immune function of Chinese soft-shelled turtle, which could result in the mass death, as we noticed that there was a clinical syndrome of infection in dead turtles. To test our hypothesis, we first performed bioinformatic annotation of several pro-inflammatory molecules (IL-1β, TNFα, IL-6, IL-12β) of Chinese soft-shelled turtle. Then, we treated the turtles in six groups, injected with Aeromonas hydrophila before acute cold stress (25 °C) and controls, after acute cold stress (15 °C) and controls as well as after the temperature was restored to 25 °C and controls, respectively. Subsequently, real-time PCR for several pro-inflammatory cytokines (IL-1β, TNFα, IL-6, IL-12β, IL-8 and IFNγ) was performed to assess the turtle immune function in spleen and intestine, 24 hours after the injection. We found that the mRNA expression levels of the immune molecules were all enhanced after acute cold stress. This change disappeared when the temperature was restored back to 25 °C. Our results suggest that abrupt temperature drop did not suppress the immune function of Chinese soft-shelled turtle in response to germ challenge after abrupt temperature drop. In contrast, it may even increase the expression of various cytokines at least, within a short time after acute cold stress. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Acute psychophysiological stress impairs human associative learning.

    PubMed

    Ehlers, M R; Todd, R M

    2017-11-01

    Addiction is increasingly discussed asa disorder of associative learning processes, with both operant and classical conditioning contributing to the development of maladaptive habits. Stress has long been known to promote drug taking and relapse and has further been shown to shift behavior from goal-directed actions towards more habitual ones. However, it remains to be investigated how acute stress may influence simple associative learning processes that occur before a habit can be established. In the present study, healthy young adults were exposed to either acute stress or a control condition half an hour before performing simple classical and operant conditioning tasks. Psychophysiological measures confirmed successful stress induction. Results of the operant conditioning task revealed reduced instrumental responding under delayed acute stress that resembled behavioral responses to lower levels of reward. The classical conditioning experiment revealed successful conditioning in both experimental groups; however, explicit knowledge of conditioning as indicated by stimulus ratings differentiated the stress and control groups. These findings suggest that operant and classical conditioning are differentially influenced by the delayed effects of acute stress with important implications for the understanding of how new habitual behaviors are initially established. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Differential expression of heat shock transcription factors and heat shock proteins after acute and chronic heat stress in laying chickens (Gallus gallus).

    PubMed

    Xie, Jingjing; Tang, Li; Lu, Lin; Zhang, Liyang; Xi, Lin; Liu, Hsiao-Ching; Odle, Jack; Luo, Xugang

    2014-01-01

    Heat stress due to high environmental temperature negatively influences animal performances. To better understand the biological impact of heat stress, laying broiler breeder chickens were subjected either to acute (step-wisely increasing temperature from 21 to 35°C within 24 hours) or chronic (32°C for 8 weeks) high temperature exposure. High temperature challenges significantly elevated body temperature of experimental birds (P<0.05). However, oxidation status of lipid and protein and expression of heat shock transcription factors (HSFs) and heat shock proteins (HSPs) 70 and 90 were differently affected by acute and chronic treatment. Tissue-specific responses to thermal challenge were also found among heart, liver and muscle. In the heart, acute heat challenge affected lipid oxidation (P = 0.05) and gene expression of all 4 HSF gene expression was upregulated (P<0.05). During chronic heat treatment, the HSP 70 mRNA level was increased (P<0.05) and HSP 90 mRNA (P<0.05) was decreased. In the liver, oxidation of protein was alleviated during acute heat challenge (P<0.05), however, gene expression HSF2, 3 and 4 and HSP 70 were highly induced (P<0.05). HSP90 expression was increased by chronic thermal treatment (P<0.05). In the muscle, both types of heat stress increased protein oxidation, but HSFs and HSPs gene expression remained unaltered. Only tendencies to increase were observed in HSP 70 (P = 0.052) and 90 (P = 0.054) gene expression after acute heat stress. The differential expressions of HSF and HSP genes in different tissues of laying broiler breeder chickens suggested that anti-heat stress mechanisms might be provoked more profoundly in the heart, by which the muscle was least protected during heat stress. In addition to HSP, HSFs gene expression could be used as a marker during acute heat stress.

  14. Response inhibition and cognitive appraisal in clients with acute stress disorder and posttraumatic stress disorder.

    PubMed

    Abolghasemi, Abass; Bakhshian, Fereshteh; Narimani, Mohammad

    2013-08-01

    The purpose of the present study was to compare response inhibition and cognitive appraisal in clients with acute stress disorder, clients with posttraumatic stress disorder, and normal individuals. This was a comparative study. The sample consisted of 40 clients with acute stress disorder, 40 patients with posttraumatic stress disorder, and 40 normal individuals from Mazandaran province selected through convenience sampling method. Data were collected using Composite International Diagnostic Interview, Stroop Color-Word Test, Posttraumatic Cognitions Inventory, and the Impact of Event Scale. Results showed that individuals with acute stress disorder are less able to inhibit inappropriate responses and have more impaired cognitive appraisals compared to those with posttraumatic stress disorder. Moreover, results showed that response inhibition and cognitive appraisal explain 75% of the variance in posttraumatic stress disorder symptoms and 38% of the variance in posttraumatic stress disorder symptoms. The findings suggest that response inhibition and cognitive appraisal are two variables that influence the severity of posttraumatic stress disorder and acute stress disorder symptoms. Also, these results have important implications for pathology, prevention, and treatment of posttraumatic stress disorder and acute stress disorder.

  15. Perceived stress at work is associated with attenuated DHEA-S response during acute psychosocial stress.

    PubMed

    Lennartsson, Anna-Karin; Theorell, Töres; Kushnir, Mark M; Bergquist, Jonas; Jonsdottir, Ingibjörg H

    2013-09-01

    Dehydroepiandrosterone (DHEA) and dehydroepiandrosterone sulfate (DHEA-S) have been suggested to play a protective role during acute psychosocial stress, because they act as antagonists to the effects of the stress hormone cortisol. This study aims to investigate whether prolonged psychosocial stress, measured as perceived stress at work during the past week, is related to the capacity to produce DHEA and DHEA-S during acute psychosocial stress. It also aims to investigate whether prolonged perceived stress affects the balance between production of cortisol and DHEA-S during acute psychosocial stress. Thirty-six healthy subjects (19 men and 17 women, mean age 37 years, SD 5 years), were included. Perceived stress at work during the past week was measured by using the Stress-Energy (SE) Questionnaire. The participants were divided into three groups based on their mean scores; Low stress, Medium stress and High stress. The participants underwent the Trier Social Stress Test (TSST) and blood samples were collected before, directly after the stress test, and after 30 min of recovery. General Linear Models were used to investigate if the Medium stress group and the High stress group differ regarding stress response compared to the Low stress group. Higher perceived stress at work was associated with attenuated DHEA-S response during acute psychosocial stress. Furthermore, the ratio between the cortisol production and the DHEA-S production during the acute stress test were higher in individuals reporting higher perceived stress at work compared to individuals reporting low perceived stress at work. There was no statistical difference in DHEA response between the groups. This study shows that prolonged stress, measured as perceived stress at work during the past week, seems to negatively affect the capacity to produce DHEA-S during acute stress. Given the protective functions of DHEA-S, attenuated DHEA-S production during acute stress may lead to higher risk for adverse

  16. Oxidative stress adaptation with acute, chronic, and repeated stress.

    PubMed

    Pickering, Andrew M; Vojtovich, Lesya; Tower, John; A Davies, Kelvin J

    2013-02-01

    Oxidative stress adaptation, or hormesis, is an important mechanism by which cells and organisms respond to, and cope with, environmental and physiological shifts in the level of oxidative stress. Most studies of oxidative stress adaption have been limited to adaptation induced by acute stress. In contrast, many if not most environmental and physiological stresses are either repeated or chronic. In this study we find that both cultured mammalian cells and the fruit fly Drosophila melanogaster are capable of adapting to chronic or repeated stress by upregulating protective systems, such as their proteasomal proteolytic capacity to remove oxidized proteins. Repeated stress adaptation resulted in significant extension of adaptive responses. Repeated stresses must occur at sufficiently long intervals, however (12-h or more for MEF cells and 7 days or more for flies), for adaptation to be successful, and the levels of both repeated and chronic stress must be lower than is optimal for adaptation to acute stress. Regrettably, regimens of adaptation to both repeated and chronic stress that were successful for short-term survival in Drosophila nevertheless also caused significant reductions in life span for the flies. Thus, although both repeated and chronic stress can be tolerated, they may result in a shorter life. Copyright © 2012 Elsevier Inc. All rights reserved.

  17. Occupational role stress is associated with higher cortisol reactivity to acute stress.

    PubMed

    Wirtz, Petra H; Ehlert, Ulrike; Kottwitz, Maria U; La Marca, Roberto; Semmer, Norbert K

    2013-04-01

    We investigated whether occupational role stress is associated with differential levels of the stress hormone cortisol in response to acute psychosocial stress. Forty-three medication-free nonsmoking men aged between 22 and 65 years (mean ± SEM: 44.5 ± 2) underwent an acute standardized psychosocial stress task combining public speaking and mental arithmetic in front of an audience. We assessed occupational role stress in terms of role conflict and role ambiguity (combined into a measure of role uncertainty) as well as further work characteristics and psychological control variables including time pressure, overcommitment, perfectionism, and stress appraisal. Moreover, we repeatedly measured salivary cortisol and blood pressure levels before and after stress exposure, and several times up to 60 min thereafter. Higher role uncertainty was associated with a more pronounced cortisol stress reactivity (p = .016), even when controlling for the full set of potential confounders (p < .001). Blood pressure stress reactivity was not associated with role uncertainty. Our findings suggest that occupational role stress in terms of role uncertainty acts as a background stressor that is associated with increased HPA-axis reactivity to acute stress. This finding may represent a potential mechanism regarding how occupational role stress may precipitate adverse health outcomes.

  18. Acute and past subjective stress influence working memory and related neural substrates.

    PubMed

    Luettgau, Lennart; Schlagenhauf, Florian; Sjoerds, Zsuzsika

    2018-05-28

    Stress has been proposed to affect cognitive control capacities, including working memory (WM) maintenance. This effect may depend on variability in stress reactivity and past subjective stress. However, as most studies employed between-subjects designs, evidence for within-subject stress effects remains scarce. To understand the role of intra-individual stress effects on WM, we adopted a within-subject design to study how acute stress, variability in stress reactivity, and past subjective stress influence behavioral and neural WM mechanisms. Thirty-four healthy males performed a WM task during functional magnetic resonance imaging (fMRI) in a control versus acute stress condition following the Trier Social Stress Test, a validated psychosocial stressor method. We tested for stress effects on WM performance and related neural activation by associating them with individual acute stress responsivity and past subjective stress experience using retrospective self-report questionnaires. We found no evidence of an effect of acute stress or related stress-reactivity on intra-individual WM performance. However, past subjective stress negatively influenced acute stress-induced changes to WM. On the neural level, acute stress reduced WM-related activation in the dorsolateral prefrontal cortex (dlPFC). The observed negative influence of inter-individual variability in past subjective stress experience on changes in WM performance, suggests that past subjective stress might induce vulnerability for impairing effects of acute stress on cognitive functioning. Because acute stress reduced WM-related dlPFC activation while WM performance remained unaffected, acute stress might boost neural processing efficiency in this group of high performing healthy individuals. Our study suggests that measures of past subjective stress should be considered when studying and interpreting the effects of acute stress on cognition. Copyright © 2018. Published by Elsevier Ltd.

  19. Acute Stress Decreases but Chronic Stress Increases Myocardial Sensitivity to Ischemic Injury in Rodents

    PubMed Central

    Eisenmann, Eric D.; Rorabaugh, Boyd R.; Zoladz, Phillip R.

    2016-01-01

    Cardiovascular disease (CVD) is the largest cause of mortality worldwide, and stress is a significant contributor to the development of CVD. The relationship between acute and chronic stress and CVD is well evidenced. Acute stress can lead to arrhythmias and ischemic injury. However, recent evidence in rodent models suggests that acute stress can decrease sensitivity to myocardial ischemia–reperfusion injury (IRI). Conversely, chronic stress is arrhythmogenic and increases sensitivity to myocardial IRI. Few studies have examined the impact of validated animal models of stress-related psychological disorders on the ischemic heart. This review examines the work that has been completed using rat models to study the effects of stress on myocardial sensitivity to ischemic injury. Utilization of animal models of stress-related psychological disorders is critical in the prevention and treatment of cardiovascular disorders in patients experiencing stress-related psychiatric conditions. PMID:27199778

  20. Acute Stress Decreases but Chronic Stress Increases Myocardial Sensitivity to Ischemic Injury in Rodents.

    PubMed

    Eisenmann, Eric D; Rorabaugh, Boyd R; Zoladz, Phillip R

    2016-01-01

    Cardiovascular disease (CVD) is the largest cause of mortality worldwide, and stress is a significant contributor to the development of CVD. The relationship between acute and chronic stress and CVD is well evidenced. Acute stress can lead to arrhythmias and ischemic injury. However, recent evidence in rodent models suggests that acute stress can decrease sensitivity to myocardial ischemia-reperfusion injury (IRI). Conversely, chronic stress is arrhythmogenic and increases sensitivity to myocardial IRI. Few studies have examined the impact of validated animal models of stress-related psychological disorders on the ischemic heart. This review examines the work that has been completed using rat models to study the effects of stress on myocardial sensitivity to ischemic injury. Utilization of animal models of stress-related psychological disorders is critical in the prevention and treatment of cardiovascular disorders in patients experiencing stress-related psychiatric conditions.

  1. Peritraumatic dissociation, acute stress, and early posttraumatic stress disorder in victims of general crime.

    PubMed

    Birmes, P; Carreras, D; Ducassé, J L; Charlet, J P; Warner, B A; Lauque, D; Schmitt, L

    2001-09-01

    To compare the relation between peritraumatic dissociation and acute stress and the early development of posttraumatic stress disorder (PTSD) in victims of general crime. A total of 48 subjects were assessed within 24 hours of the trauma, using the Peritraumatic Dissociative Experiences Questionnaire Self-Report Version (PDEQ-SRV). They were followed longitudinally to assess acute stress (2 weeks after the assault,) using the Standford Acute Stress Reaction Questionnaire (SASRQ), and posttraumatic stress (at 5 weeks), using the Clinician-Administered PTSD Scale (CAPS) and the Impact of Event Scale (IES). Among PTSD subjects mean PDEQ scores were significantly higher (mean 3, SD 0.9) than in those without PTSD (mean 2.3, SD 0.7) (t = 2.78, df 46, P = 0.007). Among PTSD subjects, mean SASRQ scores were significantly higher (mean 97.9, SD 29.2) than in those without PTSD (mean 54.8, SD 28.2) (t = 4.9, df 46, P = 0.00007). High levels of peritraumatic dissociation and acute stress following violent assault are risk factors for early PTSD. Identifying acute reexperiencing can help the clinician identify subjects at highest risk.

  2. Impairments of spatial working memory and attention following acute psychosocial stress.

    PubMed

    Olver, James S; Pinney, Myra; Maruff, Paul; Norman, Trevor R

    2015-04-01

    Few studies have investigated the effect of an acute psychosocial stress paradigm on impaired attention and working memory in humans. Further, the duration of any stress-related cognitive impairment remains unclear. The aim of this study was to examine the effect of an acute psychosocial stress paradigm, the Trier Social Stress, on cognitive function in healthy volunteers. Twenty-three healthy male and female subjects were exposed to an acute psychosocial stress task. Physiological measures (salivary cortisol, heart rate and blood pressure) and subjective stress ratings were measured at baseline, in anticipation of stress, immediately post-stress and after a period of rest. A neuropsychological test battery including spatial working memory and verbal memory was administered at each time point. Acute psychosocial stress produced significant increases in cardiovascular and subjective measures in the anticipatory and post-stress period, which recovered to baseline after rest. Salivary cortisol steadily declined over the testing period. Acute psychosocial stress impaired delayed verbal recall, attention and spatial working memory. Attention remained impaired, and delayed verbal recall continued to decline after rest. Acute psychosocial stress is associated with an impairment of a broad range of cognitive functions in humans and with prolonged abnormalities in attention and memory. Copyright © 2014 John Wiley & Sons, Ltd.

  3. Cannabinoids & Stress: impact of HU-210 on behavioral tests of anxiety in acutely stressed mice.

    PubMed

    Kinden, Renee; Zhang, Xia

    2015-05-01

    Anxiety disorders are one of the most prevalent classes of mental disorders affecting the general population, but current treatment strategies are restricted by their limited efficacy and side effect profiles. Although the cannabinoid system is speculated to be a key player in the modulation of stress responses and emotionality, the vast majority of current research initiatives had not incorporated stress exposure into their experimental designs. This study was the first to investigate the impact of exogenous cannabinoid administration in an acutely stressed mouse model, where CD1 mice were pre-treated with HU-210, a potent CB1R agonist, prior to acute stress exposure and subsequent behavioral testing. Exogenous cannabinoid administration induced distinct behavioral phenotypes in stressed and unstressed mice. While low doses of HU-210 were anxiolytic in unstressed subjects, this effect was abolished when mice were exposed to an acute stressor. The administration of higher HU-210 doses in combination with acute stress exposure led to severe locomotor deficits that were not previously observed at the same dose in unstressed subjects. These findings suggest that exogenous cannabinoids and acute stress act synergistically in an anxiogenic manner. This study underlies the importance of including stress exposure into future anxiety-cannabinoid research due to the differential impact of cannabinoid administration on stressed and unstressed subjects. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. The role of maladaptive appraisals in child acute stress reactions.

    PubMed

    Salmon, Karen; Sinclair, Emma; Bryant, Richard A

    2007-06-01

    To test the prediction of cognitive models of trauma that negative, catastrophic appraisals central to the development of psychopathological stress reactions. A cross-sectional, concurrent design was used. Sixty-six children (aged 7-13 years), who were hospitalized after traumatic injury were assessed within 4 weeks of their trauma for acute stress disorder, depression, and administered the Child Post-traumatic Cognitions Inventory (cPTCI). Parental acute stress was also assessed. Children's negative appraisals of their ongoing vulnerability accounted for 44% of the variance of acute stress reactions in children. Injury severity, depression, age, and parental acute stress levels did not account for significant additional variance. The findings provide support for cognitive models of trauma adaptation and highlight the importance of assessing children's appraisals of their traumatic experience in order to develop effective interventions.

  5. Acute Stress Symptoms in Young Children with Burns

    ERIC Educational Resources Information Center

    Stoddard, Frederick J.; Saxe, Glenn; Ronfeldt, Heidi; Drake, Jennifer E.; Burns, Jennifer; Edgren, Christy; Sheridan, Robert

    2006-01-01

    Objective: Posttraumatic stress disorder symptoms are a focus of much research with older children, but little research has been conducted with young children, who account for about 50% of all pediatric burn injuries. This is a 3-year study of 12- to 48-month-old acutely burned children to assess acute traumatic stress outcomes. The aims were to…

  6. High temperature induces apoptosis and oxidative stress in pufferfish (Takifugu obscurus) blood cells.

    PubMed

    Cheng, Chang-Hong; Yang, Fang-Fang; Liao, Shao-An; Miao, Yu-Tao; Ye, Chao-Xia; Wang, An-Li; Tan, Jia-Wen; Chen, Xiao-Yan

    2015-10-01

    Water temperature is an important environmental factor in aquaculture farming that affects the survival and growth of organisms. The change in culture water temperature may not only modify various chemical and biological processes but also affect the status of fish populations. In previous studies, high temperature induced apoptosis and oxidative stress. However, the precise mechanism and the pathways that are activated in fish are still unclear. In the present study, we investigated the effects of high temperature (34°C) on the induction of apoptosis and oxidative stress in pufferfish (Takifugu obscurus) blood cells. The data showed that high temperature exposure increased oxygen species (ROS), cytoplasmic free-Ca(2+) concentration and cell apoptosis. To test the apoptotic pathway, the expression pattern of some key apoptotic related genes including P53, Bax, caspase 9 and caspase 3 were examined. The results showed that acute high temperature stress induced up-regulation of these genes, suggesting that the p53-Bax pathway and the caspase-dependent apoptotic pathway could be involved in apoptosis induced by high temperature stress. Furthermore, the gene expression of antioxidant enzymes (Cu/Zn-SOD, Mn-SOD, CAT, GPx, and GR) and heat shock proteins (HSP90 and HSP70) in the blood cells were induced by high temperature stress. Taken together, our results showed that high temperature-induced oxidative stress may cause pufferfish blood cells apoptosis, and cooperatively activated p53-Bax and caspase-dependent apoptotic pathway. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Acute psychosocial stress reduces pain modulation capabilities in healthy men.

    PubMed

    Geva, Nirit; Pruessner, Jens; Defrin, Ruth

    2014-11-01

    Anecdotes on the ability of individuals to continue to function under stressful conditions despite injuries causing excruciating pain suggest that acute stress may induce analgesia. However, studies exploring the effect of acute experimental stress on pain perception show inconsistent results, possibly due to methodological differences. Our aim was to systematically study the effect of acute stress on pain perception using static and dynamic, state-of-the-art pain measurements. Participants were 29 healthy men who underwent the measurement of heat-pain threshold, heat-pain intolerance, temporal summation of pain, and conditioned pain modulation (CPM). Testing was conducted before and during exposure to the Montreal Imaging Stress Task (MIST), inducing acute psychosocial stress. Stress levels were evaluated using perceived ratings of stress and anxiety, autonomic variables, and salivary cortisol. The MIST induced a significant stress reaction. Although pain threshold and pain intolerance were unaffected by stress, an increase in temporal summation of pain and a decrease in CPM were observed. These changes were significantly more robust among individuals with stronger reaction to stress ("high responders"), with a significant correlation between the perception of stress and the performance in the pain measurements. We conclude that acute psychosocial stress seems not to affect the sensitivity to pain, however, it significantly reduces the ability to modulate pain in a dose-response manner. Considering the diverse effects of stress in this and other studies, it appears that the type of stress and the magnitude of its appraisal determine its interactions with the pain system. Copyright © 2014 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

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

    PubMed

    Isserlin, Leanna; Zerach, Gadi; Solomon, Zahava

    2008-10-01

    Toward the development of a unifying diagnosis for acute stress responses this article attempts to find a place for combat stress reaction (CSR) within the spectrum of other defined acute stress responses. This article critically compares the diagnostic criteria of acute stress disorder (ASD), acute stress reaction (ASR), and CSR. Prospective studies concerning the predictive value of ASD, ASR, and CSR are reviewed. Questions, recommendations, and implications for clinical practice are raised concerning the completeness of the current acute stress response diagnoses, the heterogeneity of different stressors, the scope of expected outcomes, and the importance of decline in function as an indicator of future psychological, psychiatric, and somatic distress. PsycINFO Database Record 2009 APA.

  9. Body temperature modulates the antioxidant and acute immune responses to exercise.

    PubMed

    Mestre-Alfaro, Antonia; Ferrer, Miguel D; Banquells, Montserrat; Riera, Joan; Drobnic, Franchek; Sureda, Antoni; Tur, Josep A; Pons, Antoni

    2012-06-01

    The aim of this study was to determine the effects of whole body heat in combination with exercise on the oxidative stress and acute phase immune response. Nine male endurance-trained athletes voluntarily performed two running bouts of 45 minutes at 75-80% of VO(2max) in a climatic chamber in two conditions: cold and hot humid environment. Leukocyte, neutrophil and basophil counts significantly rose after exercise in both environments; it was significantly greater in the hot environment. Lymphocyte and neutrophil antioxidant enzyme activities and carbonyl index significantly increased or decreased after exercise only in the hot environment, respectively. The lymphocytes expression of catalase, Hsp72 and CuZn-superoxide dismutase was increased in the hot environment and Sirt3 in the cold environment, mainly during recovery. In conclusion, the increased core body temperature results in the acute phase immune response associated to intense exercise and in the immune cell adaptations to counteract the oxidative stress situation.

  10. Effects of acute and chronic psychological stress on isolated islets' insulin release

    PubMed Central

    Zardooz, Homeira; Zahediasl, Saleh; Rostamkhani, Fatemeh; Farrokhi, Babak; Nasiraei, Shiva; Kazeminezhad, Behrang; Gholampour, Roohollah

    2012-01-01

    This study investigated the effects of acute and chronic psychological stress on glucose-stimulated insulin secretion from isolated pancreatic islets. Male Wistar rats were divided into two control and stressed groups; each further was allocated into fed and fasted groups. Stress was induced by communication box for one (acute), fifteen and thirty (chronic) days. After islet isolation, their number, size and insulin output were assessed. Plasma corticosterone level was determined. In fasted animals, acute stress increased basal and post stress plasma corticosterone level, while 30 days stress decreased it compared to day 1. In fed rats, acute stress increased only post stress plasma corticosterone concentration, however, after 15 days stress, it was decreased compared to day 1. Acute stress did not change insulin output; however, the insulin output was higher in the fed acutely stressed rats at 8.3 and 16.7 mM glucose than fasted ones. Chronic stress increased insulin output on day 15 in the fasted animals but decreased it on day 30 in the fed animals at 8.3 and 16.7 mM glucose. In the fasted control rats insulin output was lower than fed ones. In the chronic stressed rats insulin output at 8.3 and 16.7 mM glucose was higher in the fasted than fed rats. The number of islets increased in the fasted rats following 15 days stress. This study indicated that the response of the isolated islets from acute and chronically stressed rats are different and depends on the feeding status. PMID:27385956

  11. Acute stress affects risk taking but not ambiguity aversion.

    PubMed

    Buckert, Magdalena; Schwieren, Christiane; Kudielka, Brigitte M; Fiebach, Christian J

    2014-01-01

    Economic decisions are often made in stressful situations (e.g., at the trading floor), but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity) using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups), we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26). Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect.

  12. Endoplasmic Reticulum Stress in Ischemic and Nephrotoxic Acute Kidney Injury.

    PubMed

    Yan, Mingjuan; Shu, Shaoqun; Guo, Chunyuan; Tang, Chengyuan; Dong, Zheng

    2018-06-12

    Acute kidney injury is a medical condition characterized by kidney damage with a rapid decline of renal function, which is associated with high mortality and morbidity. Recent research has further established an intimate relationship between acute kidney injury and chronic kidney disease. Perturbations of kidney cells in acute kidney injury result in the accumulation of unfolded and misfolded proteins in the endoplasmic reticulum, leading to unfolded protein response or endoplasmic reticulum stress. In this review, we analyze the role and regulation of endoplasmic reticulum stress in acute kidney injury triggered by renal ischemia-reperfusion and cisplatin nephrotoxicity. The balance between the two major components of unfolded protein response, the adaptive pathway and the apoptotic pathway, plays a critical role in determining the cell fate in endoplasmic reticulum stress. The adaptive pathway is evoked to attenuate translation, induce chaperones, maintain protein homeostasis, and promote cell survival. Prolonged endoplasmic reticulum stress activates the apoptotic pathway, resulting in the elimination of dysfunctional cells. Therefore, regulating ER stress in kidney cells may provide a therapeutic target in acute kidney injury.

  13. Acute stress affects prospective memory functions via associative memory processes.

    PubMed

    Szőllősi, Ágnes; Pajkossy, Péter; Demeter, Gyula; Kéri, Szabolcs; Racsmány, Mihály

    2018-01-01

    Recent findings suggest that acute stress can improve the execution of delayed intentions (prospective memory, PM). However, it is unclear whether this improvement can be explained by altered executive control processes or by altered associative memory functioning. To investigate this issue, we used physical-psychosocial stressors to induce acute stress in laboratory settings. Then participants completed event- and time-based PM tasks requiring the different contribution of control processes and a control task (letter fluency) frequently used to measure executive functions. According to our results, acute stress had no impact on ongoing task performance, time-based PM, and verbal fluency, whereas it enhanced event-based PM as measured by response speed for the prospective cues. Our findings indicate that, here, acute stress did not affect executive control processes. We suggest that stress affected event-based PM via associative memory processes. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Temperature-induced physiological stress and reproductive characteristics of the migratory seahorse Hippocampus erectus during a thermal stress simulation.

    PubMed

    Qin, Geng; Johnson, Cara; Zhang, Yuan; Zhang, Huixian; Yin, Jianping; Miller, Glen; Turingan, Ralph G; Guisbert, Eric; Lin, Qiang

    2018-05-15

    Inshore-offshore migration occurs frequently in seahorse species either because of prey opportunities or because it is driven by reproduction, and variations in water temperature may dramatically change migratory seahorse behavior and physiology. The present study investigated the behavioral and physiological responses of the lined seahorse Hippocampus erectus under thermal stress and evaluated the potential effects of different temperatures on its reproduction. The results showed that the thermal tolerance of the seahorses was time dependent. Acute thermal stress (30°C, 2-10 hours) increased the basal metabolic rate (breathing rate) and the expression of stress response genes ( Hsp genes) significantly and further stimulated seahorse appetite. Chronic thermal treatment (30°C, 4 weeks) led to a persistently higher basal metabolic rate, higher stress response gene expression, and higher mortality, indicating that the seahorses could not acclimate to chronic thermal stress and might experience massive mortality due to excessive basal metabolic rates and stress damage. Additionally, no significant negative effects on gonad development or reproductive endocrine regulation genes were observed in response to chronic thermal stress, suggesting that seahorse reproductive behavior could adapt to higher-temperature conditions during migration and within seahorse breeding grounds. In conclusion, this simulation experiment indicated that temperature variations during inshore-offshore migration have no effect on reproduction but promote basal metabolic rates and stress responses significantly. Therefore, we suggest that the high observed tolerance of seahorse reproduction was in line with the inshore-offshore reproductive migration pattern of lined seahorse. © 2018. Published by The Company of Biologists Ltd.

  15. Relationship of Stress, Leukocyte Functions and Acute Ulcerative Gingivitis.

    DTIC Science & Technology

    1982-10-22

    IONAL 1jjl (I Y AN[)AAU> I,)(, 4 •. . . . .i -AD (Report Number 3 , Lf) RELATIONSHIP OF STRESS, LEUKOCYTE FUNCTION AND ACUTE ULCERATIVE GINGIVITIS...AIk £It. KEY WORDS (C~mntm. a reers old. A *1acoa and Identit by block number) Acute Necrotic Ulcerative Gingivitis (ANUG)), Stress 4 Leukocyte

  16. Acute stress affects risk taking but not ambiguity aversion

    PubMed Central

    Buckert, Magdalena; Schwieren, Christiane; Kudielka, Brigitte M.; Fiebach, Christian J.

    2014-01-01

    Economic decisions are often made in stressful situations (e.g., at the trading floor), but the effects of stress on economic decision making have not been systematically investigated so far. The present study examines how acute stress influences economic decision making under uncertainty (risk and ambiguity) using financially incentivized lotteries. We varied the domain of decision making as well as the expected value of the risky prospect. Importantly, no feedback was provided to investigate risk taking and ambiguity aversion independent from learning processes. In a sample of 75 healthy young participants, 55 of whom underwent a stress induction protocol (Trier Social Stress Test for Groups), we observed more risk seeking for gains. This effect was restricted to a subgroup of participants that showed a robust cortisol response to acute stress (n = 26). Gambling under ambiguity, in contrast to gambling under risk, was not influenced by the cortisol response to stress. These results show that acute psychosocial stress affects economic decision making under risk, independent of learning processes. Our results further point to the importance of cortisol as a mediator of this effect. PMID:24834024

  17. Stress sensitizes the brain: increased processing of unpleasant pictures after exposure to acute stress.

    PubMed

    Weymar, Mathias; Schwabe, Lars; Löw, Andreas; Hamm, Alfons O

    2012-07-01

    A key component of acute stress is a surge in vigilance that enables a prioritized processing of highly salient information to promote the organism's survival. In this study, we investigated the neural effects of acute stress on emotional picture processing. ERPs were measured during a deep encoding task, in which 40 male participants categorized 50 unpleasant and 50 neutral pictures according to arousal and valence. Before picture encoding, participants were subjected either to the Socially Evaluated Cold Pressor Test (SECPT) or to a warm water control procedure. The exposure to the SECPT resulted in increased subjective and autonomic (heart rate and blood pressure) stress responses relative to the control condition. Viewing of unpleasant relative to neutral pictures evoked enhanced late positive potentials (LPPs) over centro-parietal scalp sites around 400 msec after picture onset. Prior exposure to acute stress selectively increased the LPPs for unpleasant pictures. Moreover, the LPP magnitude for unpleasant pictures following the SECPT was positively associated with incidental free recall performance 24 hr later. The present results suggest that acute stress sensitizes the brain for increased processing of cues in the environment, particularly priming the processing of unpleasant cues. This increased processing is related to later long-term memory performance.

  18. Low-Grade Inflammation and Ambulatory Cortisol in Adolescents: Interaction Between Interviewer-Rated Versus Self-Rated Acute Stress and Chronic Stress.

    PubMed

    Schreier, Hannah M C; Chen, Edith

    To determine whether the association between self-rated or interviewer-rated recent acute stress exposures and low-grade inflammation and daily cortisol production in adolescents is moderated by chronic stress ratings. Acute and chronic stress exposures were assessed in 261 adolescents aged 13 to 16 years using a semistructured life stress interview. The negative impact of acute stressors was independently rated by both adolescents (self-rated) and interviewers (interviewer-rated). Markers of inflammation (interleukin (IL)-6, IL-1ra, C-reactive protein) were measured from peripheral blood samples obtained via antecubital venipuncture. Participants collected 4 saliva samples at home on each of 6 consecutive days for the analysis of diurnal salivary cortisol profiles. There were no main effects of acute stressors (self- and interviewer-rated) and chronic family or peer stress on adolescent inflammation markers and cortisol (p values > .10). However, the interaction between interviewer-rated acute stress and chronic family stress was significantly associated with adolescent inflammation markers (IL-6, IL-1ra). Specifically, as chronic family stress increased, the association between acute stressor impact (interviewer-rated) and inflammation markers became more positive (IL-6 (B = .054, SE = .023, p = .022); IL-1ra (B = .030, SE = .014, p = .034)). Interactions between self-rated acute stress and chronic family stress were not associated with any biological measures (p values > .10). Interactions between acute stressor impact (both self- and interviewer-rated) and chronic peer stress were also not significantly associated with any biological measures (p values > .05). Among adolescents, interviewer-based ratings of acute stressor impact may allow for better prediction of health-relevant inflammation markers than adolescents' own ratings.

  19. Low-Grade Inflammation and Ambulatory Cortisol in Adolescents: Interaction between Interviewer-rated versus Self-rated Acute Stress and Chronic Stress

    PubMed Central

    Schreier, Hannah M. C.; Chen, Edith

    2016-01-01

    Objective To determine whether the association between self-rated or interviewer-rated recent acute stress exposures and low-grade inflammation and daily cortisol production in adolescents is moderated by chronic stress ratings. Methods Acute and chronic stress exposures were assessed in 261 adolescents aged 13-16 using a semi-structured life stress interview. The negative impact of acute stressors was independently rated by both adolescents (self-rated) and interviewers (interviewer-rated). Markers of inflammation (IL-6, IL-1ra, CRP) were measured from peripheral blood samples obtained via antecubital venipuncture. Participants collected 4 saliva samples at home on each of six consecutive days for the analysis of diurnal salivary cortisol profiles. Results There were no main effects of acute stressors (self- and interviewer-rated) and chronic family or peer stress on adolescent inflammation markers and cortisol (ps > .10). However, the interaction between interviewer-rated acute stress and chronic family stress was significantly associated with adolescent inflammation markers (IL-6, IL-1ra). Specifically, as chronic family stress increased, the association between acute stressor impact (interviewer-rated) and inflammation markers became more positive (IL-6 (B = .054, SE = .023, p = .022); IL-1ra (B = .030, SE = .014, p = .034)). Interactions between self-rated acute stress and chronic family stress were not associated with any biological measures (ps > .10). Interactions between acute stressor impact (both self- and interviewer-rated) and chronic peer stress were also not significantly associated with any biological measures (ps > .05). Conclusions Among adolescents, interviewer-based ratings of acute stressor impact may allow for better prediction of health-relevant inflammation markers than adolescents’ own ratings. PMID:27490853

  20. Effect of acute heat stress on rat adrenal glands: a morphological and stereological study.

    PubMed

    Koko, Vesna; Djordjeviae, Jelena; Cvijiae, Gordana; Davidoviae, Vukosava

    2004-11-01

    The morphological and stereological structure of rat adrenal gland was analysed by light microscopy after an acute (60 min) exposure to high ambient temperature (38 degrees C). A significant increase in plasma corticotrophin (ACTH) and serum corticosterone (CORT) concentrations was observed, confirming that acute heat exposure has a strong stressful effect. Under these conditions the adrenal gland mass and volume were decreased, probably as the consequence of adrenal cortex reduction, especially that of the zona fasciculata (ZF). Histological examination revealed that many ZF cells were deprived of lipid droplets. Fibrosis was observed in all parts of the adrenal gland, both cortex and medulla, of heat stressed animals. Mitotic figures were absent in cortical cells after heat exposure, but there were no differences in ZF and zona reticularis (ZR) small blood vessels compared to nonstressed controls.

  1. Does Acute Stress Disorder Predict Posttraumatic Stress Disorder Following Bank Robbery?

    ERIC Educational Resources Information Center

    Hansen, Maj; Elklit, Ask

    2013-01-01

    Unfortunately, the number of bank robberies is increasing and little is known about the subsequent risk of posttraumatic stress disorder (PTSD). Several studies have investigated the prediction of PTSD through the presence of acute stress disorder (ASD). However, there have only been a few studies following nonsexual assault. The present study…

  2. Prefrontal Cortex Corticotropin-Releasing Factor Receptor 1 Conveys Acute Stress-Induced Executive Dysfunction.

    PubMed

    Uribe-Mariño, Andrés; Gassen, Nils C; Wiesbeck, Maximilian F; Balsevich, Georgia; Santarelli, Sara; Solfrank, Beate; Dournes, Carine; Fries, Gabriel R; Masana, Merce; Labermeier, Christiana; Wang, Xiao-Dong; Hafner, Kathrin; Schmid, Bianca; Rein, Theo; Chen, Alon; Deussing, Jan M; Schmidt, Mathias V

    2016-11-15

    The medial prefrontal cortex (mPFC) subserves complex cognition and is impaired by stress. Corticotropin-releasing factor (CRF), through CRF receptor 1 (CRFR1), constitutes a key element of the stress response. However, its contribution to the effects of stress in the mPFC remains unclear. Mice were exposed to acute social defeat stress and subsequently to either the temporal order memory (n = 11-12) or reversal learning (n = 9-11) behavioral test. Changes in mPFC Crhr1 messenger RNA levels were measured in acutely stressed mice (n = 12). Crhr1 loxP/loxP mice received either intra-mPFC adeno-associated virus-Cre or empty microinjections (n = 17-20) and then were submitted to acute stress and later to the behavioral tests. Co-immunoprecipitation was used to detect activation of the protein kinase A (PKA) signaling pathway in the mPFC of acutely stressed mice (n = 8) or intra-mPFC CRF injected mice (n = 7). Finally, mice received intra-mPFC CRF (n = 11) and/or Rp-isomer cyclic adenosine 3',5' monophosphorothioate (Rp-cAMPS) (n = 12) microinjections and underwent behavioral testing. We report acute stress-induced effects on mPFC-mediated cognition, identify CRF-CRFR1-containing microcircuits within the mPFC, and demonstrate stress-induced changes in Crhr1 messenger RNA expression. Importantly, intra-mPFC CRFR1 deletion abolishes acute stress-induced executive dysfunction, whereas intra-mPFC CRF mimics acute stress-induced mPFC dysfunction. Acute stress and intra-mPFC CRF activate the PKA signaling pathway in the mPFC, leading to cyclic AMP response element binding protein phosphorylation in intra-mPFC CRFR1-expressing neurons. Finally, PKA blockade reverses the intra-mPFC CRF-induced executive dysfunction. Taken together, these results unravel a molecular mechanism linking acute stress to executive dysfunction via CRFR1. This will aid in the development of novel therapeutic targets for stress-induced cognitive dysfunction. Copyright © 2016 Society of Biological

  3. Effects of voluntary wheel running on heart rate, body temperature, and locomotor activity in response to acute and repeated stressor exposures in rats.

    PubMed

    Masini, Cher V; Nyhuis, Tara J; Sasse, Sarah K; Day, Heidi E W; Campeau, Serge

    2011-05-01

    Stress often negatively impacts physical and mental health but it has been suggested that voluntary physical activity may benefit health by reducing some of the effects of stress. The present experiments tested whether voluntary exercise can reduce heart rate, core body temperature and locomotor activity responses to acute (novelty or loud noise) or repeated stress (loud noise). After 6 weeks of running-wheel access, rats exposed to a novel environment had reduced heart rate, core body temperature, and locomotor activity responses compared to rats housed under sedentary conditions. In contrast, none of these measures were different between exercised and sedentary rats following acute 30-min noise exposures, at either 85 or 98 dB. Following 10 weeks of running-wheel access, both groups displayed significant habituation of all these responses to 10 consecutive daily 30-min presentations of 98 dB noise stress. However, the extent of habituation of all three responses was significantly enhanced in exercised compared to sedentary animals on the last exposure to noise. These results suggest that in physically active animals, under some conditions, acute responses to stress exposure may be reduced, and response habituation to repeated stress may be enhanced, which ultimately may reduce the negative and cumulative impact of stress.

  4. Effects of voluntary wheel running on heart rate, body temperature, and locomotor activity in response to acute and repeated stressor exposures in rats

    PubMed Central

    MASINI, CHER V.; NYHUIS, TARA J.; SASSE, SARAH K.; DAY, HEIDI E. W.; CAMPEAU, SERGE

    2015-01-01

    Stress often negatively impacts physical and mental health but it has been suggested that voluntary physical activity may benefit health by reducing some of the effects of stress. The present experiments tested whether voluntary exercise can reduce heart rate, core body temperature and locomotor activity responses to acute (novelty or loud noise) or repeated stress (loud noise). After 6 weeks of running-wheel access, rats exposed to a novel environment had reduced heart rate, core body temperature, and locomotor activity responses compared to rats housed under sedentary conditions. In contrast, none of these measures were different between exercised and sedentary rats following acute 30-min noise exposures, at either 85 or 98 dB. Following 10 weeks of running-wheel access, both groups displayed significant habituation of all these responses to 10 consecutive daily 30-min presentations of 98 dB noise stress. However, the extent of habituation of all three responses was significantly enhanced in exercised compared to sedentary animals on the last exposure to noise. These results suggest that in physically active animals, under some conditions, acute responses to stress exposure may be reduced, and response habituation to repeated stress may be enhanced, which ultimately may reduce the negative and cumulative impact of stress. PMID:21438772

  5. Comparison of the effects of acute and chronic psychological stress on metabolic features in rats*

    PubMed Central

    Rostamkhani, Fatemeh; Zardooz, Homeira; Zahediasl, Saleh; Farrokhi, Babak

    2012-01-01

    This study was aimed to compare the effects of acute and chronic psychological stress on metabolic factors. Forty-two male Wistar rats were divided into control and stressed groups. Stress was applied by a communication box acutely (1 d) and chronically (15 and 30 d). Blood sampling was carried out by retro-orbital-puncture method. The plasma levels of glucose, cholesterol, triglyceride, insulin, and corticosterone were measured. In addition, feed and water intake, latency to eat and drink, adrenal and body weights were determined. Acute and chronic psychological stress did not significantly change basal plasma corticosterone levels. However, immediately (1 min) after acute exposure to stress, plasma corticosterone level increased compared to that before stress exposure. Acute stress increased plasma insulin levels significantly. Fifteen days of stress exposure resulted in plasma glucose increase. Chronic stress significantly increased feed intake, latency to eat, and adrenal weight compared to acute stress. The body weights of both control and stressed groups increased markedly during the experiment. Homeostasis model assessment of insulin resistance (HOMA-IR) index did not change significantly in the stressed group. In conclusion, application of acute and chronic psychological stress leads to different metabolic and/or behavioral changes but the metabolic changes resulting from acute exposure to stress seem to be more pronounced. PMID:23125083

  6. Social media as a shield: Facebook buffers acute stress.

    PubMed

    Rus, Holly M; Tiemensma, Jitske

    2018-03-01

    Facebook remains the most widely used social media platform. Research suggests that Facebook may both enhance and undermine psychosocial constructs related to well-being, and that it may impair physiological stress recovery. However, little is known about its influence on stress reactivity. Using novel experimental methods, this study examined how Facebook influences reactivity to an acute social stressor. Facebook users (n=104, 53 males, mean age 19.50, SD=1.73) were randomly assigned to use their own Facebook account or sit quietly with the option of reading electronic magazines before experiencing an acute social stressor. All participants showed significant changes in subjective and physiological stress markers in response to the stressor. However, participants who used Facebook experienced lower levels of psychosocial stress, physiological stress, and rated the stressor as less threatening (p's<0.05) when controlling for gender and emotional investment in the website compared to controls. Results suggest that Facebook use may buffer stress-in particular psychosocial stress-if used before experiencing an acute social stressor. This study is among the first to incorporate both objective and subjective measures in investigating the complex relationship between Facebook use and well-being. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Cold stress aggravates inflammatory responses in an LPS-induced mouse model of acute lung injury

    NASA Astrophysics Data System (ADS)

    Joo, Su-Yeon; Park, Mi-Ju; Kim, Kyun-Ha; Choi, Hee-Jung; Chung, Tae-Wook; Kim, Yong Jin; Kim, Joung Hee; Kim, Keuk-Jun; Joo, Myungsoo; Ha, Ki-Tae

    2016-08-01

    Although the relationship between environmental cold temperature and susceptibility to respiratory infection is generally accepted, the effect of ambient cold temperature on host reactivity in lung inflammation has not been fully studied. To examine the function of ambient cold temperature on lung inflammation, mice were exposed to 4 °C for 8 h each day for 14 days. In the lungs of mice exposed to cold stress, inflammatory cells in bronchoalveolar lavage (BAL) fluid and lung tissues were slightly increased by about twofold. However, the structures of pulmonary epithelial cells were kept within normal limits. Next, we examined the effect of cold stress on the inflammatory responses in a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model. The infiltration of neutrophils and inflammation of lung tissue determined by histology were significantly increased by exposure to ambient cold temperature. In addition, the production of pro-inflammatory cytokines including interleukin (IL)-12, IL-17, and monokine induced by gamma interferon (MIG) was elevated by exposure to cold stress. Therefore, we suggest that cold stress is a factor that exacerbates lung inflammation including ALI. To our knowledge, this is the first report on the relationship between cold stress and severity of lung inflammation.

  8. Media's role in broadcasting acute stress following the Boston Marathon bombings.

    PubMed

    Holman, E Alison; Garfin, Dana Rose; Silver, Roxane Cohen

    2014-01-07

    We compared the impact of media vs. direct exposure on acute stress response to collective trauma. We conducted an Internet-based survey following the Boston Marathon bombings between April 29 and May 13, 2013, with representative samples of residents from Boston (n = 846), New York City (n = 941), and the remainder of the United States (n = 2,888). Acute stress symptom scores were comparable in Boston and New York [regression coefficient (b) = 0.43; SE = 1.42; 95% confidence interval (CI), -2.36, 3.23], but lower nationwide when compared with Boston (b = -2.21; SE = 1.07; 95% CI, -4.31, -0.12). Adjusting for prebombing mental health (collected prospectively), demographics, and prior collective stress exposure, six or more daily hours of bombing-related media exposure in the week after the bombings was associated with higher acute stress than direct exposure to the bombings (continuous acute stress symptom total: media exposure b = 15.61 vs. direct exposure b = 5.69). Controlling for prospectively collected prebombing television-watching habits did not change the findings. In adjusted models, direct exposure to the 9/11 terrorist attacks and the Sandy Hook School shootings were both significantly associated with bombing-related acute stress; Superstorm Sandy exposure wasn't. Prior exposure to similar and/or violent events may render some individuals vulnerable to the negative effects of collective traumas. Repeatedly engaging with trauma-related media content for several hours daily shortly after collective trauma may prolong acute stress experiences and promote substantial stress-related symptomatology. Mass media may become a conduit that spreads negative consequences of community trauma beyond directly affected communities.

  9. Loneliness and acute stress reactivity: A systematic review of psychophysiological studies.

    PubMed

    Brown, Eoin G; Gallagher, Stephen; Creaven, Ann-Marie

    2018-05-01

    Physiological reactivity to acute stress has been proposed as a potential biological mechanism by which loneliness may lead to negative health outcomes such as cardiovascular disease. This review was conducted to investigate the association between loneliness and physiological responses to acute stress. A series of electronic databases were systematically searched (PsycARTICLES, PsycINFO, Medline, CINAHL Plus, EBSCOhost, PubMed, SCOPUS, Web of Science, Science Direct) for relevant studies, published up to October 2016. Eleven studies were included in the review. Overall, the majority of studies reported positive associations between loneliness and acute stress responses, such that higher levels of loneliness were predictive of exaggerated physiological reactions. However, in a few studies, loneliness was also linked with decreased stress responses for particular physiological outcomes, indicating the possible existence of blunted relationships. There was no clear pattern suggesting any sex- or stressor-based differences in these associations. The available evidence supports a link between loneliness and atypical physiological reactivity to acute stress. A key finding of this review was that greater levels of loneliness are associated with exaggerated blood pressure and inflammatory reactivity to acute stress. However, there was some indication that loneliness may also be related to blunted cardiac, cortisol, and immune responses. Overall, this suggests that stress reactivity could be one of the biological mechanisms through which loneliness impacts upon health. © 2017 Society for Psychophysiological Research.

  10. Parent-Child Agreement Regarding Children's Acute Stress: The Role of Parent Acute Stress Reactions

    ERIC Educational Resources Information Center

    Kassam-Adams, Nancy; Garcia-Espana, J. Felipe; Miller, Victoria A.; Winston, Flaura

    2006-01-01

    Objective: We examined parent--child agreement regarding child acute stress disorder (ASD) and the relationship between parent ASD symptoms and parent ratings of child ASD. Method: Parent-child dyads (N = 219; child age 8-17 years) were assessed within 1 month of child injury. Parent--child agreement was examined regarding child ASD presence,…

  11. Effects of acute and chronic psychological stress on platelet aggregation in mice.

    PubMed

    Matsuhisa, Fumikazu; Kitamura, Nobuo; Satoh, Eiki

    2014-03-01

    Although psychological stress has long been known to alter cardiovascular function, there have been few studies on the effect of psychological stress on platelets, which play a pivotal role in cardiovascular disease. In the present study, we investigated the effects of acute and chronic psychological stress on the aggregation of platelets and platelet cytosolic free calcium concentration ([Ca(2+)]i). Mice were subjected to both transportation stress (exposure to novel environment, psychological stress) and restraint stress (psychological stress) for 2 h (acute stress) or 3 weeks (2 h/day) (chronic stress). In addition, adrenalectomized mice were subjected to similar chronic stress (both transportation and restraint stress for 3 weeks). The aggregation of platelets from mice and [Ca(2+)]i was determined by light transmission assay and fura-2 fluorescence assay, respectively. Although acute stress had no effect on agonist-induced platelet aggregation, chronic stress enhanced the ability of the platelet agonists thrombin and ADP to stimulate platelet aggregation. However, chronic stress failed to enhance agonist-induced increase in [Ca(2+)]i. Adrenalectomy blocked chronic stress-induced enhancement of platelet aggregation. These results suggest that chronic, but not acute, psychological stress enhances agonist-stimulated platelet aggregation independently of [Ca(2+)]i increase, and the enhancement may be mediated by stress hormones secreted from the adrenal glands.

  12. Acute Heat Stress Induces Differential Gene Expressions in the Testes of a Broiler-Type Strain of Taiwan Country Chickens

    PubMed Central

    Wang, Shih-Han; Cheng, Chuen-Yu; Tang, Pin-Chi; Chen, Chih-Feng; Chen, Hsin-Hsin; Lee, Yen-Pai; Huang, San-Yuan

    2015-01-01

    The expression of testicular genes following acute heat stress has been reported in layer-type roosters, but few similar studies have been conducted on broilers. This study investigated the effect of acute heat stress on the gene expression in the testes of a broiler-type strain of Taiwan country chickens. Roosters were subjected to acute heat stress (38°C) for 4 h, and then exposed to 25°C, with testes collected 0, 2, and 6 h after the cessation of heat stress, using non-heat-stressed roosters as controls (n = 3 roosters per group). The body temperature and respiratory rate increased significantly (p<0.05) during the heat stress. The numbers of apoptotic cells increased 2 h after the acute heat stress (79 ± 7 vs. 322 ± 192, control vs. heat stress; p<0.05), which was earlier than the time of increase in layer-type roosters. Based on a chicken 44 K oligo microarray, 163 genes were found to be expressed significantly different in the testes of the heat-stressed chickens from those of the controls, including genes involved in the response to stimulus, protein metabolism, signal transduction, cell adhesion, transcription, and apoptosis. The mRNA expressions of upregulated genes, including HSP25, HSP90AA1, HSPA2, and LPAR2, and of downregulated genes, including CDH5, CTNNA3, EHF, CIRBP, SLA, and NTF3, were confirmed through quantitative real-time polymerase chain reaction (qRT-PCR). Moreover, numerous transcripts in the testes exhibited distinct expressions between the heat-stressed broiler-type and layer-type chickens. We concluded that the transcriptional responses of testes to acute heat stress may differ between the broiler-type and layer-type roosters. Whether the differential expression patterns associate with the heat-tolerance in the strains require a further exploration. PMID:25932638

  13. Acute heat stress induces differential gene expressions in the testes of a broiler-type strain of Taiwan country chickens.

    PubMed

    Wang, Shih-Han; Cheng, Chuen-Yu; Tang, Pin-Chi; Chen, Chih-Feng; Chen, Hsin-Hsin; Lee, Yen-Pai; Huang, San-Yuan

    2015-01-01

    The expression of testicular genes following acute heat stress has been reported in layer-type roosters, but few similar studies have been conducted on broilers. This study investigated the effect of acute heat stress on the gene expression in the testes of a broiler-type strain of Taiwan country chickens. Roosters were subjected to acute heat stress (38°C) for 4 h, and then exposed to 25°C, with testes collected 0, 2, and 6 h after the cessation of heat stress, using non-heat-stressed roosters as controls (n = 3 roosters per group). The body temperature and respiratory rate increased significantly (p<0.05) during the heat stress. The numbers of apoptotic cells increased 2 h after the acute heat stress (79 ± 7 vs. 322 ± 192, control vs. heat stress; p<0.05), which was earlier than the time of increase in layer-type roosters. Based on a chicken 44 K oligo microarray, 163 genes were found to be expressed significantly different in the testes of the heat-stressed chickens from those of the controls, including genes involved in the response to stimulus, protein metabolism, signal transduction, cell adhesion, transcription, and apoptosis. The mRNA expressions of upregulated genes, including HSP25, HSP90AA1, HSPA2, and LPAR2, and of downregulated genes, including CDH5, CTNNA3, EHF, CIRBP, SLA, and NTF3, were confirmed through quantitative real-time polymerase chain reaction (qRT-PCR). Moreover, numerous transcripts in the testes exhibited distinct expressions between the heat-stressed broiler-type and layer-type chickens. We concluded that the transcriptional responses of testes to acute heat stress may differ between the broiler-type and layer-type roosters. Whether the differential expression patterns associate with the heat-tolerance in the strains require a further exploration.

  14. Acute stress induces selective alterations in cost/benefit decision-making.

    PubMed

    Shafiei, Naghmeh; Gray, Megan; Viau, Victor; Floresco, Stan B

    2012-09-01

    Acute stress can exert beneficial or detrimental effects on different forms of cognition. In the present study, we assessed the effects of acute restraint stress on different forms of cost/benefit decision-making, and some of the hormonal and neurochemical mechanisms that may underlie these effects. Effort-based decision-making was assessed where rats chose between a low effort/reward (1 press=2 pellets) or high effort/reward option (4 pellets), with the effort requirement increasing over 4 blocks of trials (2, 5, 10, and 20 lever presses). Restraint stress for 1 h decreased preference for the more costly reward and induced longer choice latencies. Control experiments revealed that the effects on decision-making were not mediated by general reductions in motivation or preference for larger rewards. In contrast, acute stress did not affect delay-discounting, when rats chose between a small/immediate vs larger/delayed reward. The effects of stress on decision-making were not mimicked by treatment with physiological doses of corticosterone (1-3 mg/kg). Blockade of dopamine receptors with flupenthixol (0.25 mg/kg) before restraint did not attenuate stress-induced effects on effort-related choice, but abolished effects on choice latencies. These data suggest that acute stress interferes somewhat selectively with cost/benefit evaluations concerning effort costs. These effects do not appear to be mediated solely by enhanced glucocorticoid activity, whereas dopaminergic activation may contribute to increased deliberation times induced by stress. These findings may provide insight into impairments in decision-making and anergia associated with stress-related disorders, such as depression.

  15. Acute Stress Induces Selective Alterations in Cost/Benefit Decision-Making

    PubMed Central

    Shafiei, Naghmeh; Gray, Megan; Viau, Victor; Floresco, Stan B

    2012-01-01

    Acute stress can exert beneficial or detrimental effects on different forms of cognition. In the present study, we assessed the effects of acute restraint stress on different forms of cost/benefit decision-making, and some of the hormonal and neurochemical mechanisms that may underlie these effects. Effort-based decision-making was assessed where rats chose between a low effort/reward (1 press=2 pellets) or high effort/reward option (4 pellets), with the effort requirement increasing over 4 blocks of trials (2, 5, 10, and 20 lever presses). Restraint stress for 1 h decreased preference for the more costly reward and induced longer choice latencies. Control experiments revealed that the effects on decision-making were not mediated by general reductions in motivation or preference for larger rewards. In contrast, acute stress did not affect delay-discounting, when rats chose between a small/immediate vs larger/delayed reward. The effects of stress on decision-making were not mimicked by treatment with physiological doses of corticosterone (1–3 mg/kg). Blockade of dopamine receptors with flupenthixol (0.25 mg/kg) before restraint did not attenuate stress-induced effects on effort-related choice, but abolished effects on choice latencies. These data suggest that acute stress interferes somewhat selectively with cost/benefit evaluations concerning effort costs. These effects do not appear to be mediated solely by enhanced glucocorticoid activity, whereas dopaminergic activation may contribute to increased deliberation times induced by stress. These findings may provide insight into impairments in decision-making and anergia associated with stress-related disorders, such as depression. PMID:22569506

  16. Acute stress promotes post-injury brain regeneration in fish.

    PubMed

    Sinyakov, Michael S; Haimovich, Amihai; Avtalion, Ramy R

    2017-12-01

    The central nervous system and the immune system, the two major players in homeostasis, operate in the ongoing bidirectional interaction. Stress is the third player that exerts strong effect on these two 'supersystems'; yet, its impact is studied much less. In this work employing carp model, we studied the influence of preliminary stress on neural and immune networks involved in post-injury brain regeneration. The relevant in vivo models of air-exposure stress and precisely directed cerebellum injury have been developed. Neuronal regeneration was evaluated by using specific tracers of cell proliferation and differentiation. Involvement of immune networks was accessed by monitoring the expression of selected T cells markers. Contrast difference between acute and chronic stress manifested in the fact that chronically stressed fish did not survive the brain injury. Neuronal regeneration appeared as a biphasic process whereas involvement of immune system proceeded as a monophasic route. In stressed fish, immune response was fast and accompanied or even preceded neuronal regeneration. In unstressed subjects, immune response took place on the second phase of neuronal regeneration. These findings imply an intrinsic regulatory impact of acute stress on neuronal and immune factors involved in post-injury brain regeneration. Stress activates both neuronal and immune defense mechanisms and thus contributes to faster regeneration. In this context, paradoxically, acute preliminary stress might be considered a distinct asset in speeding up the following post-injury brain regeneration. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Openness to experience and adapting to change: Cardiovascular stress habituation to change in acute stress exposure.

    PubMed

    Ó Súilleabháin, Páraic S; Howard, Siobhán; Hughes, Brian M

    2018-05-01

    Underlying psychophysiological mechanisms of effect linking openness to experience to health outcomes, and particularly cardiovascular well-being, are unknown. This study examined the role of openness in the context of cardiovascular responsivity to acute psychological stress. Continuous cardiovascular response data were collected for 74 healthy young female adults across an experimental protocol, including differing counterbalanced acute stressors. Openness was measured via self-report questionnaire. Analysis of covariance revealed openness was associated with systolic blood pressure (SBP; p = .016), and diastolic blood pressure (DBP; p = .036) responsivity across the protocol. Openness was also associated with heart rate (HR) responding to the initial stress exposure (p = .044). Examination of cardiovascular adaptation revealed that higher openness was associated with significant SBP (p = .001), DBP (p = .009), and HR (p = .002) habituation in response to the second differing acute stress exposure. Taken together, the findings suggest persons higher in openness are characterized by an adaptive cardiovascular stress response profile within the context of changing acute stress exposures. This study is also the first to demonstrate individual differences in cardiovascular adaptation across a protocol consisting of differing stress exposures. More broadly, this research also suggests that future research may benefit from conceptualizing an adaptive fitness of openness within the context of change. In summary, the present study provides evidence that higher openness stimulates short-term stress responsivity, while ensuring cardiovascular habituation to change in stress across time. © 2017 Society for Psychophysiological Research.

  18. Acute stress disorder in hospitalised victims of 26/11-terror attack on Mumbai, India.

    PubMed

    Balasinorwala, Vanshree Patil; Shah, Nilesh

    2010-11-01

    The 26/11 terror attacks on Mumbai have been internationally denounced. Acute stress disorder is common in victims of terror. To find out the prevalence and to correlate acute stress disorder, 70 hospitalised victims of terror were assessed for presence of the same using DSM-IV TR criteria. Demographic data and clinical variables were also collected. Acute stress disorder was found in 30% patients. On demographic profile and severity of injury, there were some interesting observations and differences between the victims who developed acute stress disorder and those who did not; though none of the differences reached the level of statistical significance. This study documents the occurrence of acute stress disorder in the victims of 26/11 terror attack.

  19. PTSD, Acute Stress, Performance and Decision-Making in Emergency Service Workers.

    PubMed

    Regehr, Cheryl; LeBlanc, Vicki R

    2017-06-01

    Despite research identifying high levels of stress and traumatic stress symptoms among those in the emergency services, the impact of these symptoms on performance and hence public safety remains uncertain. This review paper discusses a program of research that has examined the effects of prior critical incident exposure, acute stress, and current post-traumatic symptoms on the performance and decision-making during an acutely stressful event among police officers, police communicators, paramedics and child protection workers. Four studies, using simulation methods involving video simulators, human-patient simulators, and/or standardized patients, examined the performance of emergency workers in typical workplace situations related to their individual profession. Results varied according to level of acuity of stress and the nature of performance and decision-making. There was no evidence that PTSD had a direct impact on global performance on tasks for which emergency responders are highly trained. However, PTSD was associated with assessment of risk in situations that required professional judgement. Further, individuals experiencing PTSD symptoms reported higher levels of acute stress when faced with high acuity situations. Acute stress in these studies was associated with performance deficits on complex cognitive tasks, verbal memory impairment and heightened assessment of risk. © 2017 American Academy of Psychiatry and the Law.

  20. Biological markers of stress in pediatric acute burn injury.

    PubMed

    Brown, Nadia J; Kimble, Roy M; Rodger, Sylvia; Ware, Robert S; McWhinney, Brett C; Ungerer, Jacobus P J; Cuttle, Leila

    2014-08-01

    Burns and their associated wound care procedures evoke significant stress and anxiety, particularly for children. Little is known about the body's physiological stress reactions throughout the stages of re-epithelialization following an acute burn injury. Previously, serum and urinary cortisol have been used to measure stress in burn patients, however these measures are not suitable for a pediatric burn outpatient setting. To assess the sensitivity of salivary cortisol and sAA in detecting stress during acute burn wound care procedures and to investigate the body's physiological stress reactions throughout burn re-epithelialization. Seventy-seven participants aged four to thirteen years who presented with an acute burn injury to the burn center at the Royal Children's Hospital, Brisbane, Australia, were recruited between August 2011 and August 2012. Both biomarkers were responsive to the stress of burn wound care procedures. sAA levels were on average 50.2 U/ml higher (p<0.001) at 10 min post-dressing removal compared to baseline levels. Salivary cortisol levels showed a blunted effect with average levels at ten minutes post dressing removal decreasing by 0.54 nmol/L (p<0.001) compared to baseline levels. sAA levels were associated with pain (p=0.021), no medication (p=0.047) and Child Trauma Screening Questionnaire scores at three months post re-epithelialization (p=0.008). Similarly, salivary cortisol was associated with no medication (p<0.001), pain scores (p=0.045) and total body surface area of the burn (p=0.010). Factors which support the use of sAA over salivary cortisol to assess stress during morning acute burn wound care procedures include; sensitivity, morning clinic times relative to cortisol's diurnal peaks, and relative cost. Copyright © 2013 Elsevier Ltd and ISBI. All rights reserved.

  1. Social identity influences stress appraisals and cardiovascular reactions to acute stress exposure.

    PubMed

    Gallagher, Stephen; Meaney, Sarah; Muldoon, Orla T

    2014-09-01

    This study tested a recent theoretical development in stress research to see whether group membership influenced cardiovascular reactions following exposure to acute stress. Participants (N = 104) were exposed to a message in which a maths test was described as stressful or challenging by an ingroup member (a student) or outgroup member (a stress disorder sufferer). Systolic blood pressure and diastolic blood pressure(DBP) and heart rate (HR) were monitored throughout a standard reactivity study. As expected, a significant interaction was found; relative to those who were told that the task was challenging, ingroup members reported more stress and had higher DBP and HR reactivity when told by an ingroup member that the maths task was stressful; task information did not have the same effect for outgroup members. These results indicate that informational support is not constant but varies as a function of group membership. Finally, this recent development in stress research may prove useful for those interested in investigating the interactions between social, psychological and physiological processes underlying health disparities. What is already known on this subject? Stress is a common risk factor for hypertension and coronary heart disease. Social support has been found to reduce cardiovascular reactions to acute psychological stress. The influence of social support on stress varies as a consequence of social identity. What does this study add? The social group that one belongs to influences how one appraises and responds to stress. Social identity provides a useful framework for understanding how social processes are associated with health disparities. © 2013 The British Psychological Society.

  2. Effect of acute acoustic stress on anorectal function sensation in healthy human.

    PubMed

    Gonlachanvit, S; Rhee, J; Sun, W M; Chey, W D

    2005-04-01

    Little is known about the effects of acute acoustic stress on anorectal function. To determine the effects of acute acoustic stress on anorectal function and sensation in healthy volunteers. Ten healthy volunteers (7 M, 3 F, mean age 34 +/- 3 years) underwent anorectal manometry, testing of rectal compliance and sensation using a barostat with and without acute noise stress on separate days. Rectal perception was assessed using an ascending method of limits protocol and a 5-point Likert scale. Arousal and anxiety status were evaluated using a visual analogue scale. Acoustic stress significantly increased anxiety score (P < 0.05). Rectal compliance was significantly decreased with acoustic stress compared with control P (P < 0.000001). In addition, less intraballoon volume was needed to induce the sensation of severe urgency with acoustic stress (P < 0.05). Acoustic stress had no effect on hemodynamic parameters, anal sphincter pressure, threshold for first sensation, sensation of stool, or pain. Acute acoustic stimulation increased anxiety scores, decreased rectal compliance, and enhanced perception of severe urgency to balloon distention but did not affect anal sphincter pressure in healthy volunteers. These results may offer insight into the pathogenesis of stress-in-induced diarrhoea and faecal urgency.

  3. Acute Stress Symptoms in Children: Results From an International Data Archive

    ERIC Educational Resources Information Center

    Kassam-Adams, Nancy; Palmieri, Patrick A.; Rork, Kristine; Delahanty, Douglas L.; Kenardy, Justin; Kohser, Kristen L.; Landolt, Markus A.; Le Brocque, Robyne; Marsac, Meghan L.; Meiser-Stedman, Richard; Nixon, Reginald D.V.; Bui, Eric; McGrath, Caitlin

    2012-01-01

    Objective: To describe the prevalence of acute stress disorder (ASD) symptoms and to examine proposed "DSM-5" symptom criteria in relation to concurrent functional impairment in children and adolescents. Method: From an international archive, datasets were identified that included assessment of acute traumatic stress reactions and…

  4. The Relationship between Acute Stress Disorder and Posttraumatic Stress Disorder Following Cancer

    ERIC Educational Resources Information Center

    Kangas, Maria; Henry, Jane L.; Bryant, Richard A.

    2005-01-01

    In this study, the authors investigated the relationship between acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) following cancer diagnosis. Patients who were recently diagnosed with 1st onset head and neck or lung malignancy (N = 82) were assessed for ASD within the initial month following their diagnosis and reassessed (n =…

  5. Acute stress cardiomyopathy and deaths associated with electronic weapons.

    PubMed

    Cevik, Cihan; Otahbachi, Mohammad; Miller, Elizabeth; Bagdure, Satish; Nugent, Kenneth M

    2009-03-06

    Deaths associated with the use of electronic weapons almost always occur in young men involved in either civil disturbances or criminal activity. These situations are associated with high levels of circulating catecholamines and frequently associated with drug intoxication. The mechanism for these deaths is unclear. Clinical studies indicate that these high voltage electrical pulses do not cause cardiac arrhythmia. Acute stress cardiomyopathy provides an alternative explanation for deaths associated with electronic weapons and may provide a better explanation for the usual time course associated with taser deaths. Patients with acute stress cardiomyopathy usually have had an emotional or physical stress, have high circulating levels of catecholamines, present with an acute coronary syndrome but have normal coronary vessels without significant thrombus formation. They have unusual left ventricular dysfunction with so-called apical ballooning. This presentation has been attributed to the direct effects of catecholamines on myocardial cell function. Alternative explanations include vasospasm in the coronary microcirculation and/or acute thrombosis followed by rapid thrombolysis. Similar events could occur during the high stress situations associated with the use of electronic weapons. These events also likely explain restraint-related deaths which occur in independent of any use of electronic weapons. Forensic pathologists have the opportunity to provide important details about the pathogenesis of these deaths through histological studies and careful evaluation of coronary vessels.

  6. Perceived Chronic Stress Exposure Modulates Reward-Related Medial Prefrontal Cortex Responses to Acute Stress in Depression

    PubMed Central

    Kumar, Poornima; Slavich, George M.; Berghorst, Lisa H.; Treadway, Michael T.; Brooks, Nancy H.; Dutra, Sunny J.; Greve, Douglas N.; O'Donovan, Aoife; Bleil, Maria E.; Maninger, Nicole; Pizzagalli, Diego A.

    2015-01-01

    Introduction Major depressive disorder (MDD) is often precipitated by life stress and growing evidence suggests that stress-induced alterations in reward processing may contribute to such risk. However, no human imaging studies have examined how recent life stress exposure modulates the neural systems that underlie reward processing in depressed and healthy individuals. Methods In this proof-of-concept study, 12 MDD and 10 psychiatrically healthy individuals were interviewed using the Life Events and Difficulties Schedule (LEDS) to assess their perceived levels of recent acute and chronic life stress exposure. Additionally, each participant performed a monetary incentive delay task under baseline (no-stress) and stress (social-evaluative) conditions during functional MRI. Results Across groups, medial prefrontal cortex (mPFC) activation to reward feedback was greater during acute stress versus no-stress conditions in individuals with greater perceived stressor severity. Under acute stress, depressed individuals showed a positive correlation between perceived stressor severity levels and reward-related mPFC activation (r = 0.79, p = 0.004), whereas no effect was found in healthy controls. Moreover, for depressed (but not healthy) individuals, the correlations between the stress (r = 0.79) and no-stress (r = −0.48) conditions were significantly different. Finally, relative to controls, depressed participants showed significantly reduced mPFC grey matter, but functional findings remained when accounting for structural differences. Limitation Small sample size, which warrants replication. Conclusion Depressed individuals experiencing greater recent life stress recruited the mPFC more under stress when processing rewards. Our results represent an initial step toward elucidating mechanisms underlying stress sensitization and recurrence in depression. PMID:25898329

  7. Media’s role in broadcasting acute stress following the Boston Marathon bombings

    PubMed Central

    Holman, E. Alison; Garfin, Dana Rose; Silver, Roxane Cohen

    2014-01-01

    We compared the impact of media vs. direct exposure on acute stress response to collective trauma. We conducted an Internet-based survey following the Boston Marathon bombings between April 29 and May 13, 2013, with representative samples of residents from Boston (n = 846), New York City (n = 941), and the remainder of the United States (n = 2,888). Acute stress symptom scores were comparable in Boston and New York [regression coefficient (b) = 0.43; SE = 1.42; 95% confidence interval (CI), −2.36, 3.23], but lower nationwide when compared with Boston (b = −2.21; SE = 1.07; 95% CI, −4.31, −0.12). Adjusting for prebombing mental health (collected prospectively), demographics, and prior collective stress exposure, six or more daily hours of bombing-related media exposure in the week after the bombings was associated with higher acute stress than direct exposure to the bombings (continuous acute stress symptom total: media exposure b = 15.61 vs. direct exposure b = 5.69). Controlling for prospectively collected prebombing television-watching habits did not change the findings. In adjusted models, direct exposure to the 9/11 terrorist attacks and the Sandy Hook School shootings were both significantly associated with bombing-related acute stress; Superstorm Sandy exposure wasn't. Prior exposure to similar and/or violent events may render some individuals vulnerable to the negative effects of collective traumas. Repeatedly engaging with trauma-related media content for several hours daily shortly after collective trauma may prolong acute stress experiences and promote substantial stress-related symptomatology. Mass media may become a conduit that spreads negative consequences of community trauma beyond directly affected communities. PMID:24324161

  8. The role of dehydroepiandrosterone on functional innate immune responses to acute stress.

    PubMed

    Prall, Sean P; Larson, Emilee E; Muehlenbein, Michael P

    2017-12-01

    The androgen dehydroepiandrosterone (DHEA) responds to stress activation, exhibits anti-glucocorticoid properties, and modulates immunity in diverse ways, yet little is known of its role in acute stress responses. In this study, the effects of DHEA and its sulfate ester DHEA-S on human male immune function during exposure to an acute stressor is explored. Variation in DHEA, DHEA-S, testosterone, and cortisol, along with bacterial killing assays, was measured in response to a modified Trier Social Stress test in 27 young adult males. Cortisol was positively related to salivary innate immunity but only for participants who also exhibited high DHEA responses. Additionally, DHEA positively and DHEA-S negatively predicted salivary immunity, but the opposite was observed for serum-based innate immunity. The DHEA response to acute stress appears to be an important factor in stress-mediated immunological responses, with differential effects on immunity dependent upon the presence of other hormones, primarily cortisol and DHEA-S. These results suggest that DHEA plays an important role, alongside other hormones, in modulating immunological shifts during acute stress. Copyright © 2017 John Wiley & Sons, Ltd.

  9. Prolonged Effects of Acute Stress on Decision-Making under Risk: A Human Psychophysiological Study

    PubMed Central

    Yamakawa, Kaori; Ohira, Hideki; Matsunaga, Masahiro; Isowa, Tokiko

    2016-01-01

    This study investigates the prolonged effects of physiological responses induced by acute stress on risk-taking in decision-making. Participants were divided into a Stress group (N = 14) and a Control group (N = 12). The Trier Social Stress Test was administered as an acute stressor, and reading was administered as a control task; thereafter, participants performed a decision-making task in which they needed to choose a sure option or a gamble option in Gain and Loss frame trials 2 h after (non-) exposure to the stressor. Increased cortisol, adrenaline, heart rate (HR), and subjective stress levels validated acute stress manipulation. Stressed participants made fewer risky choices only in the Gain domain, whereas no effect of stress was shown in the Loss domain. Deceleration of HR reflecting attention was greater for Gains compared with Losses only in the Stress group. Risk avoidance was determined by increased levels of cortisol caused by acute stress. These results suggest that processes regarding glucocorticoid might be involved in the prolonged effects of acute stress on the evaluation of risks and the monitoring of outcomes in decision-making. PMID:27679566

  10. Acute stress shifts the balance between controlled and automatic processes in prospective memory.

    PubMed

    Möschl, Marcus; Walser, Moritz; Plessow, Franziska; Goschke, Thomas; Fischer, Rico

    2017-10-01

    In everyday life we frequently rely on our abilities to postpone intentions until later occasions (prospective memory; PM) and to deactivate completed intentions even in stressful situations. Yet, little is known about the effects of acute stress on these abilities. In the present work we investigated the impact of acute stress on PM functioning under high task demands. (1) Different from previous studies, in which intention deactivation required mostly low processing demands, we used salient focal PM cues to induce high processing demands during intention-deactivation phases. (2) We systematically manipulated PM-monitoring demands in a nonfocal PM task that required participants to monitor for either one or six specific syllables that could occur in ongoing-task words. Eighty participants underwent the Trier Social Stress Test, a standardized stress induction protocol, or a standardized control situation, before performing a computerized PM task. Our primary interests were whether PM performance, PM-monitoring costs, aftereffects of completed intentions and/or commission-error risk would differ between stressed and non-stressed individuals and whether these effects would differ under varying task demands. Results revealed that PM performance and aftereffects of completed intentions during subsequent performance were not affected by acute stress induction, replicating previous findings. Under high demands on intention deactivation (focal condition), however, acute stress produced a nominal increase in erroneous PM responses after intention completion (commission errors). Most importantly, under high demands on PM monitoring (nonfocal condition), acute stress led to a substantial reduction in PM-monitoring costs. These findings support ideas of selective and demand-dependent effects of acute stress on cognitive functioning. Under high task demands, acute stress might induce a shift in processing strategy towards resource-saving behavior, which seems to increase the

  11. Executive functioning performance predicts subjective and physiological acute stress reactivity: preliminary results.

    PubMed

    Hendrawan, Donny; Yamakawa, Kaori; Kimura, Motohiro; Murakami, Hiroki; Ohira, Hideki

    2012-06-01

    Individual differences in baseline executive functioning (EF) capacities have been shown to predict state anxiety during acute stressor exposure. However, no previous studies have clearly demonstrated the relationship between EF and physiological measures of stress. The present study investigated the efficacy of several well-known EF tests (letter fluency, Stroop test, and Wisconsin Card Sorting Test) in predicting both subjective and physiological stress reactivity during acute psychosocial stress exposure. Our results show that letter fluency served as the best predictor for both types of reactivity. Specifically, the higher the letter fluency score, the lower the acute stress reactivity after controlling for the baseline stress response, as indicated by lower levels of state anxiety, negative mood, salivary cortisol, and skin conductance. Moreover, the predictive power of the letter fluency test remained significant for state anxiety and cortisol indices even after further adjustments for covariates by adding the body mass index (BMI) as a covariate. Thus, good EF performance, as reflected by high letter fluency scores, may dampen acute stress responses, which suggests that EF processes are directly associated with aspects of stress regulation. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Stress-induced core temperature changes in pigeons (Columba livia).

    PubMed

    Bittencourt, Myla de Aguiar; Melleu, Fernando Falkenburger; Marino-Neto, José

    2015-02-01

    Changes in body temperature are significant physiological consequences of stressful stimuli in mammals and birds. Pigeons (Columba livia) prosper in (potentially) stressful urban environments and are common subjects in neurobehavioral studies; however, the thermal responses to stress stimuli by pigeons are poorly known. Here, we describe acute changes in the telemetrically recorded celomatic (core) temperature (Tc) in pigeons given a variety of potentially stressful stimuli, including transfer to a novel cage (ExC) leading to visual isolation from conspecifics, the presence of the experimenter (ExpR), gentle handling (H), sham intracelomatic injections (SI), and the induction of the tonic immobility (TI) response. Transfer to the ExC cage provoked short-lived hyperthermia (10-20 min) followed by a long-lasting and substantial decrease in Tc, which returned to baseline levels 2 h after the start of the test. After a 2-hour stay in the ExC, the other potentially stressful stimuli evoked only weak, marginally significant hyperthermic (ExpR, IT) or hypothermic (SI) responses. Stimuli delivered 26 h after transfer to the ExC induced definite and intense increases in Tc (ExpR, H) or hypothermic responses (SI). These Tc changes appear to be unrelated to modifications in general activity (as measured via telemetrically recorded actimetric data). Repeated testing failed to affect the hypothermic responses to the transference to the ExC, even after nine trials and at 1- or 8-day intervals, suggesting that the social (visual) isolation from conspecifics may be a strong and poorly controllable stimulus in this species. The present data indicated that stress-induced changes in Tc may be a consistent and reliable physiological parameter of stress but that they may also show stressor type-, direction- and species-specific attributes. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Rigid patterns of effortful choice behavior after acute stress in rats.

    PubMed

    Hart, Evan E; Stolyarova, Alexandra; Conoscenti, Michael A; Minor, Thomas R; Izquierdo, Alicia

    2017-01-01

    Physical effort is a common cost of acquiring rewards, and decreased effort is a feature of many neuropsychiatric disorders. Stress affects performance on several tests of cognition and decision making in both humans and nonhumans. Only a few recent reports show impairing effects of stress in operant tasks involving effort and cognitive flexibility. Brain regions affected by stress, such as the medial prefrontal cortex and amygdala, are also implicated in mediating effortful choices. Here, we assessed effort-based decision making after an acute stress procedure known to induce persistent impairment in shuttle escape and elevated plasma corticosterone. In these animals, we also probed levels of polysialyted neural cell adhesion molecule (PSA-NCAM), a marker of structural plasticity, in medial frontal cortex and amygdala. We found that animals that consistently worked for high magnitude rewards continued to do so, even after acute shock stress. We also found that PSA-NCAM was increased in both regions after effortful choice experience but not after shock stress alone. These findings are discussed with reference to the existing broad literature on cognitive effects of stress and in the context of how acute stress may bias effortful decisions to a rigid pattern of responding.

  14. Dorsal CA1 interneurons contribute to acute stress-induced spatial memory deficits.

    PubMed

    Yu, Jing-Ying; Fang, Ping; Wang, Chi; Wang, Xing-Xing; Li, Kun; Gong, Qian; Luo, Ben-Yan; Wang, Xiao-Dong

    2018-06-01

    Exposure to severely stressful experiences disrupts the activity of neuronal circuits and impairs declarative memory. GABAergic interneurons coordinate neuronal network activity, but their involvement in stress-evoked memory loss remains to be elucidated. Here, we provide evidence that interneurons in area CA1 of the dorsal hippocampus partially modulate acute stress-induced memory deficits. In adult male mice, both acute forced swim stress and restraint stress impaired hippocampus-dependent spatial memory and increased the density of c-fos-positive interneurons in the dorsal CA1. Selective activation of dorsal CA1 interneurons by chemogenetics disrupted memory performance in the spatial object recognition task. In comparison, anxiety-related behavior, spatial working memory and novel object recognition memory remained intact when dorsal CA1 interneurons were overactivated. Moreover, chemogenetic activation of dorsal CA1 interneurons suppressed the activity of adjacent pyramidal neurons, whereas a single exposure to forced swim stress but not restraint stress increased the activity of CA1 pyramidal neurons. However, chemogenetic inhibition of dorsal CA1 interneurons led to spatial memory impairments and failed to attenuate acute stress-induced memory loss. These findings suggest that acute stress may overactivate interneurons in the dorsal CA1, which reduces the activity of pyramidal neurons and in turn disrupts long-term memory. Copyright © 2018 Elsevier Ltd. All rights reserved.

  15. Perceived life stress exposure modulates reward-related medial prefrontal cortex responses to acute stress in depression.

    PubMed

    Kumar, Poornima; Slavich, George M; Berghorst, Lisa H; Treadway, Michael T; Brooks, Nancy H; Dutra, Sunny J; Greve, Douglas N; O'Donovan, Aoife; Bleil, Maria E; Maninger, Nicole; Pizzagalli, Diego A

    2015-07-15

    Major depressive disorder (MDD) is often precipitated by life stress and growing evidence suggests that stress-induced alterations in reward processing may contribute to such risk. However, no human imaging studies have examined how recent life stress exposure modulates the neural systems that underlie reward processing in depressed and healthy individuals. In this proof-of-concept study, 12 MDD and 10 psychiatrically healthy individuals were interviewed using the Life Events and Difficulties Schedule (LEDS) to assess their perceived levels of recent acute and chronic life stress exposure. Additionally, each participant performed a monetary incentive delay task under baseline (no-stress) and stress (social-evaluative) conditions during functional MRI. Across groups, medial prefrontal cortex (mPFC) activation to reward feedback was greater during acute stress versus no-stress conditions in individuals with greater perceived stressor severity. Under acute stress, depressed individuals showed a positive correlation between perceived stressor severity levels and reward-related mPFC activation (r=0.79, p=0.004), whereas no effect was found in healthy controls. Moreover, for depressed (but not healthy) individuals, the correlations between the stress (r=0.79) and no-stress (r=-0.48) conditions were significantly different. Finally, relative to controls, depressed participants showed significantly reduced mPFC gray matter, but functional findings remained robust while accounting for structural differences. Small sample size, which warrants replication. Depressed individuals experiencing greater recent life stress recruited the mPFC more under stress when processing rewards. Our results represent an initial step toward elucidating mechanisms underlying stress sensitization and recurrence in depression. Copyright © 2015 Elsevier B.V. All rights reserved.

  16. Acute stress enhances learning and memory by activating acid-sensing ion channels in rats.

    PubMed

    Ye, Shunjie; Yang, Rong; Xiong, Qiuju; Yang, Youhua; Zhou, Lianying; Gong, Yeli; Li, Changlei; Ding, Zhenhan; Ye, Guohai; Xiong, Zhe

    2018-04-15

    Acute stress has been shown to enhance learning and memory ability, predominantly through the action of corticosteroid stress hormones. However, the valuable targets for promoting learning and memory induced by acute stress and the underlying molecular mechanisms remain unclear. Acid-sensing ion channels (ASICs) play an important role in central neuronal systems and involves in depression, synaptic plasticity and learning and memory. In the current study, we used a combination of electrophysiological and behavioral approaches in an effort to explore the effects of acute stress on ASICs. We found that corticosterone (CORT) induced by acute stress caused a potentiation of ASICs current via glucocorticoid receptors (GRs) not mineralocorticoid receptors (MRs). Meanwhile, CORT did not produce an increase of ASICs current by pretreated with GF109203X, an antagonist of protein kinase C (PKC), whereas CORT did result in a markedly enhancement of ASICs current by bryostatin 1, an agonist of PKC, suggesting that potentiation of ASICs function may be depended on PKC activating. More importantly, an antagonist of ASICs, amiloride (10 μM) reduced the performance of learning and memory induced by acute stress, which is further suggesting that ASICs as the key components involves in cognitive processes induced by acute stress. These results indicate that acute stress causes the enhancement of ASICs function by activating PKC signaling pathway, which leads to potentiated learning and memory. Copyright © 2018 Elsevier Inc. All rights reserved.

  17. Surgeons' and surgical trainees' acute stress in real operations or simulation: A systematic review.

    PubMed

    Georgiou, Konstantinos; Larentzakis, Andreas; Papavassiliou, Athanasios G

    2017-12-01

    Acute stress in surgery is ubiquitous and has an immediate impact on surgical performance and patient safety. Surgeons react with several coping strategies; however, they recognise the necessity of formal stress management training. Thus, stress assessment is a direct need. Surgical simulation is a validated standardised training milieu designed to replicate real-life situations. It replicates stress, prevents biases, and provides objective metrics. The complexity of stress mechanisms makes stress measurement difficult to quantify and interpret. This systematic review aims to identify studies that have used acute stress estimation measurements in surgeons or surgical trainees during real operations or surgical simulation, and to collectively present the rationale of these tools, with special emphasis in salivary markers. A search strategy was implemented to retrieve relevant articles from MEDLINE and SCOPUS databases. The 738 articles retrieved were reviewed for further evaluation according to the predetermined inclusion/exclusion criteria. Thirty-three studies were included in this systematic review. The methods for acute stress assessment varied greatly among studies with the non-invasive techniques being the most commonly used. Subjective and objective tests for surgeons' acute stress assessment are being presented. There is a broad spectrum of acute mental stress assessment tools in the surgical field and simulation and salivary biomarkers have recently gained popularity. There is a need to maintain a consistent methodology in future research, towards a deeper understanding of acute stress in the surgical field. Copyright © 2017 Royal College of Surgeons of Edinburgh (Scottish charity number SC005317) and Royal College of Surgeons in Ireland. Published by Elsevier Ltd. All rights reserved.

  18. Acute restraint stress induces endothelial dysfunction: role of vasoconstrictor prostanoids and oxidative stress.

    PubMed

    Carda, Ana P P; Marchi, Katia C; Rizzi, Elen; Mecawi, André S; Antunes-Rodrigues, José; Padovan, Claudia M; Tirapelli, Carlos R

    2015-01-01

    We hypothesized that acute stress would induce endothelial dysfunction. Male Wistar rats were restrained for 2 h within wire mesh. Functional and biochemical analyses were conducted 24 h after the 2-h period of restraint. Stressed rats showed decreased exploration on the open arms of an elevated-plus maze (EPM) and increased plasma corticosterone concentration. Acute restraint stress did not alter systolic blood pressure, whereas it increased the in vitro contractile response to phenylephrine and serotonin in endothelium-intact rat aortas. NG-nitro-l-arginine methyl ester (l-NAME; nitric oxide synthase, NOS, inhibitor) did not alter the contraction induced by phenylephrine in aortic rings from stressed rats. Tiron, indomethacin and SQ29548 reversed the increase in the contractile response to phenylephrine induced by restraint stress. Increased systemic and vascular oxidative stress was evident in stressed rats. Restraint stress decreased plasma and vascular nitrate/nitrite (NOx) concentration and increased aortic expression of inducible (i) NOS, but not endothelial (e) NOS. Reduced expression of cyclooxygenase (COX)-1, but not COX-2, was observed in aortas from stressed rats. Restraint stress increased thromboxane (TX)B(2) (stable TXA(2) metabolite) concentration but did not affect prostaglandin (PG)F2α concentration in the aorta. Restraint reduced superoxide dismutase (SOD) activity, whereas concentrations of hydrogen peroxide (H(2)O(2)) and reduced glutathione (GSH) were not affected. The major new finding of our study is that restraint stress increases vascular contraction by an endothelium-dependent mechanism that involves increased oxidative stress and the generation of COX-derived vasoconstrictor prostanoids. Such stress-induced endothelial dysfunction could predispose to the development of cardiovascular diseases.

  19. Sex-specific hippocampal 5-hydroxymethylcytosine is disrupted in response to acute stress

    PubMed Central

    Papale, Ligia A.; Li, Sisi; Madrid, Andy; Zhang, Qi; Chen, Li; Chopra, Pankaj; Jin, Peng; Keleş, Sündüz; Alisch, Reid S.

    2016-01-01

    Environmental stress is among the most important contributors to increased susceptibility to develop psychiatric disorders. While it is well known that acute environmental stress alters gene expression, the molecular mechanisms underlying these changes remain largely unknown. 5-hydroxymethylcytosine (5hmC) is a novel environmentally sensitive epigenetic modification that is highly enriched in neurons and is associated with active neuronal transcription. Recently, we reported a genome-wide disruption of hippocampal 5hmC in male mice following acute stress that was correlated to altered transcript levels of genes in known stress related pathways. Since sex-specific endocrine mechanisms respond to environmental stimulus by altering the neuronal epigenome, we examined the genome-wide profile of hippocampal 5hmC in female mice following exposure to acute stress and identified 363 differentially hydroxymethylated regions (DhMRs) linked to known (e.g., Nr3c1 and Ntrk2) and potentially novel genes associated with stress response and psychiatric disorders. Integration of hippocampal expression data from the same female mice found stress-related hydroxymethylation correlated to altered transcript levels. Finally, characterization of stress-induced sex-specific 5hmC profiles in the hippocampus revealed 778 sex-specific acute stress-induced DhMRs some of which were correlated to altered transcript levels that produce sex-specific isoforms in response to stress. Together, the alterations in 5hmC presented here provide a possible molecular mechanism for the adaptive sex-specific response to stress that may augment the design of novel therapeutic agents that will have optimal effectiveness in each sex. PMID:27576189

  20. Salivary Markers of Inflammation in Response to Acute Stress

    PubMed Central

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

    2014-01-01

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

  1. Self-esteem levels and cardiovascular and inflammatory responses to acute stress.

    PubMed

    O'Donnell, Katie; Brydon, Lena; Wright, Caroline E; Steptoe, Andrew

    2008-11-01

    Acute mental stress tests have helped to clarify the pathways through which psychosocial factors are linked to disease risk. This methodology is now being used to investigate potentially protective psychosocial factors. We investigated whether global self-esteem might buffer cardiovascular and inflammatory responses to acute stress. One hundred and one students completed the Rosenberg Self-Esteem Scale. Heart rate and heart rate variability (HRV) were recorded for 5 min periods at baseline, during two mental stress tasks, (a speech and a color-word task) and 10, 25 and 40 min into a recovery period. Plasma levels of tumor-necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-1 receptor antagonist (IL-1Ra) were assessed at baseline, immediately post-stress and after 45 min recovery. Repeated measures analysis of variance demonstrated that heart rate levels were lower across all time points in those with high self-esteem, although heart rate reactivity to stress was not related to self-esteem. There were no differences in baseline HRV, TNF-alpha, IL-6 or IL-1Ra. Multiple linear regressions revealed that greater self-esteem was associated with a smaller reduction in heart rate variability during the speech task, but not the color-word task. Greater self-esteem was associated with smaller TNF-alpha and IL-1Ra responses immediately following acute stress and smaller IL-1Ra responses at 45 min post-stress. In conclusion, global self-esteem is associated with lower heart rate and attenuated HRV and inflammatory responses to acute stress. These responses could be processes through which self-esteem protects against the development of disease.

  2. Effect of acute psychological stress on response inhibition: An event-related potential study.

    PubMed

    Qi, Mingming; Gao, Heming; Liu, Guangyuan

    2017-04-14

    This study aimed to investigate the effect of acute psychological stress on response inhibition and its electrophysiological correlates using a dual-task paradigm. Acute stress was induced by a primary task (mental arithmetic task), which consisted of a stress block and a control block. Response inhibition was measured using a secondary task (Go/NoGo task). In each trial, a Go/NoGo stimulus was presented immediately after the mental arithmetic task. The results revealed increased subjective stress and negative affect for the stress relative to control block, suggesting that the mental arithmetic task triggered a reliable stress response. ERPs locked to the Go/NoGo stimuli revealed that decreased P2 and increased N2 components were evoked for the stress block compared to the control block. These results demonstrated that acute psychological stress alters the response inhibition process by reducing the early selective attention process and enhancing the cognitive control process. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Sex-specific hippocampal 5-hydroxymethylcytosine is disrupted in response to acute stress.

    PubMed

    Papale, Ligia A; Li, Sisi; Madrid, Andy; Zhang, Qi; Chen, Li; Chopra, Pankaj; Jin, Peng; Keleş, Sündüz; Alisch, Reid S

    2016-12-01

    Environmental stress is among the most important contributors to increased susceptibility to develop psychiatric disorders. While it is well known that acute environmental stress alters gene expression, the molecular mechanisms underlying these changes remain largely unknown. 5-hydroxymethylcytosine (5hmC) is a novel environmentally sensitive epigenetic modification that is highly enriched in neurons and is associated with active neuronal transcription. Recently, we reported a genome-wide disruption of hippocampal 5hmC in male mice following acute stress that was correlated to altered transcript levels of genes in known stress related pathways. Since sex-specific endocrine mechanisms respond to environmental stimulus by altering the neuronal epigenome, we examined the genome-wide profile of hippocampal 5hmC in female mice following exposure to acute stress and identified 363 differentially hydroxymethylated regions (DhMRs) linked to known (e.g., Nr3c1 and Ntrk2) and potentially novel genes associated with stress response and psychiatric disorders. Integration of hippocampal expression data from the same female mice found stress-related hydroxymethylation correlated to altered transcript levels. Finally, characterization of stress-induced sex-specific 5hmC profiles in the hippocampus revealed 778 sex-specific acute stress-induced DhMRs some of which were correlated to altered transcript levels that produce sex-specific isoforms in response to stress. Together, the alterations in 5hmC presented here provide a possible molecular mechanism for the adaptive sex-specific response to stress that may augment the design of novel therapeutic agents that will have optimal effectiveness in each sex. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Chronic and Acute Stress Promote Overexploitation in Serial Decision Making.

    PubMed

    Lenow, Jennifer K; Constantino, Sara M; Daw, Nathaniel D; Phelps, Elizabeth A

    2017-06-07

    Many decisions that humans make resemble foraging problems in which a currently available, known option must be weighed against an unknown alternative option. In such foraging decisions, the quality of the overall environment can be used as a proxy for estimating the value of future unknown options against which current prospects are compared. We hypothesized that such foraging-like decisions would be characteristically sensitive to stress, a physiological response that tracks biologically relevant changes in environmental context. Specifically, we hypothesized that stress would lead to more exploitative foraging behavior. To test this, we investigated how acute and chronic stress, as measured by changes in cortisol in response to an acute stress manipulation and subjective scores on a questionnaire assessing recent chronic stress, relate to performance in a virtual sequential foraging task. We found that both types of stress bias human decision makers toward overexploiting current options relative to an optimal policy. These findings suggest a possible computational role of stress in decision making in which stress biases judgments of environmental quality. SIGNIFICANCE STATEMENT Many of the most biologically relevant decisions that we make are foraging-like decisions about whether to stay with a current option or search the environment for a potentially better one. In the current study, we found that both acute physiological and chronic subjective stress are associated with greater overexploitation or staying at current options for longer than is optimal. These results suggest a domain-general way in which stress might bias foraging decisions through changing one's appraisal of the overall quality of the environment. These novel findings not only have implications for understanding how this important class of foraging decisions might be biologically implemented, but also for understanding the computational role of stress in behavior and cognition more broadly

  5. Chronic and Acute Stress Promote Overexploitation in Serial Decision Making

    PubMed Central

    Lenow, Jennifer K.; Constantino, Sara M.

    2017-01-01

    Many decisions that humans make resemble foraging problems in which a currently available, known option must be weighed against an unknown alternative option. In such foraging decisions, the quality of the overall environment can be used as a proxy for estimating the value of future unknown options against which current prospects are compared. We hypothesized that such foraging-like decisions would be characteristically sensitive to stress, a physiological response that tracks biologically relevant changes in environmental context. Specifically, we hypothesized that stress would lead to more exploitative foraging behavior. To test this, we investigated how acute and chronic stress, as measured by changes in cortisol in response to an acute stress manipulation and subjective scores on a questionnaire assessing recent chronic stress, relate to performance in a virtual sequential foraging task. We found that both types of stress bias human decision makers toward overexploiting current options relative to an optimal policy. These findings suggest a possible computational role of stress in decision making in which stress biases judgments of environmental quality. SIGNIFICANCE STATEMENT Many of the most biologically relevant decisions that we make are foraging-like decisions about whether to stay with a current option or search the environment for a potentially better one. In the current study, we found that both acute physiological and chronic subjective stress are associated with greater overexploitation or staying at current options for longer than is optimal. These results suggest a domain-general way in which stress might bias foraging decisions through changing one's appraisal of the overall quality of the environment. These novel findings not only have implications for understanding how this important class of foraging decisions might be biologically implemented, but also for understanding the computational role of stress in behavior and cognition more broadly

  6. The dynamic interplay between acute psychosocial stress, emotion and autobiographical memory.

    PubMed

    Sheldon, Signy; Chu, Sonja; Nitschke, Jonas P; Pruessner, Jens C; Bartz, Jennifer A

    2018-06-06

    Although acute psychosocial stress can impact autobiographical memory retrieval, the nature of this effect is not entirely clear. One reason for this ambiguity is because stress can have opposing effects on the different stages of autobiographical memory retrieval. We addressed this issue by testing how acute stress affects three stages of the autobiographical memory retrieval - accessing, recollecting and reconsolidating a memory. We also investigate the influence of emotion valence on this effect. In a between-subjects design, participants were first exposed to an acute psychosocial stressor or a control task. Next, the participants were shown positive, negative or neutral retrieval cues and asked to access and describe autobiographical memories. After a three to four day delay, participants returned for a second session in which they described these autobiographical memories. During initial retrieval, stressed participants were slower to access memories than were control participants; moreover, cortisol levels were positively associated with response times to access positively-cued memories. There were no effects of stress on the amount of details used to describe memories during initial retrieval, but stress did influence memory detail during session two. During session two, stressed participants recovered significantly more details, particularly emotional ones, from the remembered events than control participants. Our results indicate that the presence of stress impairs the ability to access consolidated autobiographical memories; moreover, although stress has no effect on memory recollection, stress alters how recollected experiences are reconsolidated back into memory traces.

  7. The Prosodic Evolution of West Slavic in the Context of the Neo-Acute Stress

    ERIC Educational Resources Information Center

    Feldstein, Ronald F.

    1975-01-01

    Because of neo-acute stress--or transferred acute stress--long vowel prosody in West Slavic had a special evolution. Two kinds of long vowel evolution are examined. The nature of transitionality across Slavic territory from tonal opposition to distinctive stress placement is pointed out. (SC)

  8. Exposure to acute stress enhances decision-making competence: Evidence for the role of DHEA.

    PubMed

    Shields, Grant S; Lam, Jovian C W; Trainor, Brian C; Yonelinas, Andrew P

    2016-05-01

    Exposure to acute stress can impact performance on numerous cognitive abilities, but little is known about how acute stress affects real-world decision-making ability. In the present study, we induced acute stress with a standard laboratory task involving uncontrollable socio-evaluative stress and subsequently assessed decision-making ability using the Adult Decision Making Competence index. In addition, we took baseline and post-test saliva samples from participants to examine associations between decision-making competence and adrenal hormones. Participants in the stress induction group showed enhanced decision-making competence, relative to controls. Further, although both cortisol and dehydroepiandrosterone (DHEA) reactivity predicted decision-making competence when considered in isolation, DHEA was a significantly better predictor than cortisol when both hormones were considered simultaneously. Thus, our results show that exposure to acute stress can have beneficial effects on the cognitive ability underpinning real-world decision-making and that this effect relates to DHEA reactivity more than cortisol. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Exposure to Acute Stress Enhances Decision-Making Competence: Evidence for the Role of DHEA

    PubMed Central

    Shields, Grant S.; Lam, Jovian C. W.; Trainor, Brian C.; Yonelinas, Andrew P.

    2016-01-01

    Exposure to acute stress can impact performance on numerous cognitive abilities, but little is known about how acute stress affects real-world decision-making ability. In the present study, we induced acute stress with a standard laboratory task involving uncontrollable socio-evaluative stress and subsequently assessed decision-making ability using the Adult Decision Making Competence index. In addition, we took baseline and post-test saliva samples from participants to examine associations between decision-making competence and adrenal hormones. Participants in the stress induction group showed enhanced decision-making competence, relative to controls. Further, although both cortisol and dehydroepiandrosterone (DHEA) reactivity predicted decision-making competence when considered in isolation, DHEA was a significantly better predictor than cortisol when both hormones were considered simultaneously. Thus, our results show that exposure to acute stress can have beneficial effects on the cognitive ability underpinning real-world decision-making and that this effect relates to DHEA reactivity more than cortisol. PMID:26874561

  10. Acute social stress increases biochemical and self report markers of stress without altering spatial learning in humans.

    PubMed

    Klopp, Christine; Garcia, Carlos; Schulman, Allan H; Ward, Christopher P; Tartar, Jaime L

    2012-01-01

    Spatial learning is shown to be influenced by acute stress in both human and other animals. However, the intricacies of this relationship are unclear. Based on prior findings we hypothesized that compared to a control condition, a social stress condition would not affect spatial learning performance despite elevated biochemical markers of stress. The present study tested the effects of social stress in human males and females on a subsequent spatial learning task. Social stress induction consisted of evaluative stress (the Trier Social Stress Test, TSST) compared to a placebo social stress. Compared to the placebo condition, the TSST resulted in significantly elevated cortisol and alpha amylase levels at multiple time points following stress induction. In accord, cognitive appraisal measures also showed that participants in the TSST group experienced greater perceived stress compared to the placebo group. However, there were no group differences in performance on a spatial learning task. Our findings suggest that unlike physiological stress, social stress does not result in alterations in spatial learning in humans. It is possible that moderate social evaluative stress in humans works to prevent acute stress-mediated alterations in hippocampal learning processes..

  11. [Acute Stress and Broken Heart Syndrome. A Case Report].

    PubMed

    Vergel, Juliana; Tamayo-Orozco, Sebastián; Vallejo-Gómez, Andrés Felipe; Posada, María Teresa; Restrepo, Diana

    Stress has been associated with an acute heart failure syndrome of important morbidity and mortality. Case report and non-systematic review of the relevant literature. A 65-year-old woman with a history of an untreated generalized anxiety disorder, whom after the violent death of her son presented with oppressive chest pain irradiated to neck and left superior extremity, lasting for more than 30minutes, initial clinical suspect suggests acute coronary syndrome. Tako-tsubo cardiomyopathy is characterized by a reversible left ventricular dysfunction and wall movement abnormalities, without any compromise of the coronary arteries, associated to high plasma levels of catecholamines which in most cases correlates with an acute stress of emotional or physical type. Tako-tsubo cardiomyopathy has to be considered by physicians among the differential diagnosis when facing a patient with suspected acute coronary syndrome, especially in post-menopausal women with a history of psychiatric comorbidities such as a generalized anxiety disorder. Copyright © 2016 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  12. Cancer, acute stress disorder, and repressive coping.

    PubMed

    Pedersen, Anette Fischer; Zachariae, Robert

    2010-02-01

    The purpose of this study was to investigate the association between repressive coping style and Acute Stress Disorder (ASD) in a sample of cancer patients. A total of 112 cancer patients recently diagnosed with cancer participated in the study. ASD was assessed by the Stanford Acute Stress Reaction Questionnaire, and repressive coping was assessed by a combination of scores from the Marlowe-Crowne Social Desirability Scale, and the Bendig version of the Taylor Manifest Anxiety Scale. Significantly fewer patients classified as "repressors" were diagnosed with ASD compared to patients classified as "non-repressors". However, further investigations revealed that the lower incidence of ASD in repressors apparently was caused by a low score on anxiety and not by an interaction effect between anxiety and defensiveness. Future studies have to investigate whether different psychological mechanisms are responsible for the lower incidence of ASD in repressors and true low-anxious patients.

  13. Leptin concentrations in response to acute stress predict subsequent intake of comfort foods

    PubMed Central

    Tomiyama, A. Janet; Schamarek, Imke; Lustig, Robert H.; Kirschbaum, Clemens; Puterman, Eli; Havel, Peter J.; Epel, Elissa S.

    2012-01-01

    Both animals and humans show a tendency toward eating more “comfort food” (high fat, sweet food) after acute stress. Such stress eating may be contributing to the obesity epidemic, and it is important to understand the underlying psychobiological mechanisms. Prior investigations have studied what makes individuals eat more after stress; this study investigates what might make individuals eat less. Leptin has been shown to increase following a laboratory stressor, and is known to affect eating behavior. This study examined whether leptin reactivity accounts for individual differences in stress eating. To test this, we exposed forty women to standardized acute psychological laboratory stress (Trier Social Stress Test) while blood was sampled repeatedly for measurements of plasma leptin. We then measured food intake after the stressor in 29 of these women. Increasing leptin during the stressor predicted lower intake of comfort food. These initial findings suggest that acute changes in leptin may be one of the factors modulating down the consumption of comfort food following stress. PMID:22579988

  14. Profiling of differential gene expression in the hypothalamus of broiler-type Taiwan country chickens in response to acute heat stress.

    PubMed

    Tu, Wei-Lin; Cheng, Chuen-Yu; Wang, Shih-Han; Tang, Pin-Chi; Chen, Chih-Feng; Chen, Hsin-Hsin; Lee, Yen-Pai; Chen, Shuen-Ei; Huang, San-Yuan

    2016-02-01

    Acute heat stress severely impacts poultry production. The hypothalamus acts as a crucial center to regulate body temperature, detect temperature changes, and modulate the autonomic nervous system and endocrine loop for heat retention and dissipation. The purpose of this study was to investigate global gene expression in the hypothalamus of broiler-type B strain Taiwan country chickens after acute heat stress. Twelve 30-week-old hens were allocated to four groups. Three heat-stressed groups were subjected to acute heat stress at 38 °C for 2 hours without recovery (H2R0), with 2 hours of recovery (H2R2), and with 6 hours of recovery (H2R6). The control hens were maintained at 25 °C. At the end, hypothalamus samples were collected for gene expression analysis. The results showed that 24, 11, and 25 genes were upregulated and 41, 15, and 42 genes were downregulated in H2R0, H2R2, and H2R6 treatments, respectively. The expressions of gonadotropin-releasing hormone 1 (GNRH1), heat shock 27-kDa protein 1 (HSPB1), neuropeptide Y (NPY), and heat shock protein 25 (HSP25) were upregulated at all recovery times after heat exposure. Conversely, the expression of TPH2 was downregulated at all recovery times. A gene ontology analysis showed that most of the differentially expressed genes were involved in biological processes including cellular processes, metabolic processes, localization, multicellular organismal processes, developmental processes, and biological regulation. A functional annotation analysis showed that the differentially expressed genes were related to the gene networks of responses to stress and reproductive functions. These differentially expressed genes might be essential and unique key factors in the heat stress response of the hypothalamus in chickens. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Repeated, but Not Acute, Stress Suppresses Inflammatory Plasma Extravasation

    NASA Astrophysics Data System (ADS)

    Strausbaugh, Holly J.; Dallman, Mary F.; Levine, Jon D.

    1999-12-01

    Clinical findings suggest that inflammatory disease symptoms are aggravated by ongoing, repeated stress, but not by acute stress. We hypothesized that, compared with single acute stressors, chronic repeated stress may engage different physiological mechanisms that exert qualitatively different effects on the inflammatory response. Because inhibition of plasma extravasation, a critical component of the inflammatory response, has been associated with increased disease severity in experimental arthritis, we tested for a potential repeated stress-induced inhibition of plasma extravasation. Repeated, but not single, exposures to restraint stress produced a profound inhibition of bradykinin-induced synovial plasma extravasation in the rat. Experiments examining the mechanism of inhibition showed that the effect of repeated stress was blocked by adrenalectomy, but not by adrenal medullae denervation, suggesting that the adrenal cortex mediates this effect. Consistent with known effects of stress and with mediation by the adrenal cortex, restraint stress evoked repeated transient elevations of plasma corticosterone levels. This elevated corticosterone was necessary and sufficient to produce inhibition of plasma extravasation because the stress-induced inhibition was blocked by preventing corticosterone synthesis and, conversely, induction of repeated transient elevations in plasma corticosterone levels mimicked the effects of repeated stress. These data suggest that repetition of a mild stressor can induce changes in the physiological state of the animal that enable a previously innocuous stressor to inhibit the inflammatory response. These findings provide a potential explanation for the clinical association between repeated stress and aggravation of inflammatory disease symptoms and provide a model for study of the biological mechanisms underlying the stress-induced aggravation of chronic inflammatory diseases.

  16. Alpha adrenergic regulation of celiac blood flow and plasma catecholamine response during acute heat stress in fed cockerels.

    PubMed

    Bottje, W G; Harrison, P C

    1986-08-01

    Hubbard cockerels with chronically implanted electromagnetic blood flow probes on the celiac artery were used to establish a relationship between changes in postprandial celiac mean blood flow (MBF) and plasma catecholamines during a acute heat exposure. Five min after the elevation of ambient temperature from 25 to 37 C, there were concomitant reductions (P less than .05) in celiac MBF, norepinephrine (NE), and heart rate (HR). After 50 min of heat stress, rectal temperature (Tr), respiratory rate (RR), plasma epinephrine (E), and celiac vascular resistance (CVR) were significantly greater (P less than .05) than preheat stress thermoneutral control values. During the thermoneutral recovery period, all parameters returned to values comparable to preheat exposure control with the exception of NE, which tended (P less than .1) to remain lower. To determine the role of the sympathetic nervous system in regulating postprandial celiac MBF during acute heat exposure, chronically instrumented cockerels were infused with phenoxybenzamine, an alpha-adrenergic receptor-blocking agent. Alpha-receptor blockade attenuated both postprandial intestinal hyperemia under thermoneutral conditions as well as the heat-induced reduction of postprandial celiac MBF. The results of these studies implicate the sympathetic nervous system in the regulation of postprandial celiac MBF in heat-stressed cockerels and indicate a possible alpha-adrenergic-mediated mechanism involved in postprandial intestinal hyperemia.

  17. Acute stress induces hyperacusis in women with high levels of emotional exhaustion.

    PubMed

    Hasson, Dan; Theorell, Töres; Bergquist, Jonas; Canlon, Barbara

    2013-01-01

    Hearing problems is one of the top ten public health disorders in the general population and there is a well-established relationship between stress and hearing problems. The aim of the present study was to explore if an acute stress will increase auditory sensitivity (hyperacusis) in individuals with high levels of emotional exhaustion (EE). Hyperacusis was assessed using uncomfortable loudness levels (ULL) in 348 individuals (140 men; 208 women; age 23-71 years). Multivariate analyses (ordered logistic regression), were used to calculate odds ratios, including interacting or confounding effects of age, gender, ear wax and hearing loss (PTA). Two-way ANCOVAs were used to assess possible differences in mean ULLs between EE groups pre- and post-acute stress task (a combination of cold pressor, emotional Stroop and Social stress/video recording). There were no baseline differences in mean ULLs between the three EE groups (one-way ANOVA). However, after the acute stress exposure there were significant differences in ULL means between the EE-groups in women. Post-hoc analyses showed that the differences in mean ULLs were between those with high vs. low EE (range 5.5-6.5 dB). Similar results were found for frequencies 0.5 and 1 kHz. The results demonstrate that women with high EE-levels display hyperacusis after an acute stress task. The odds of having hyperacusis were 2.5 (2 kHz, right ear; left ns) and 2.2 (4 kHz, right ear; left ns) times higher among those with high EE compared to those with low levels. All these results are adjusted for age, hearing loss and ear wax. Women with high levels of emotional exhaustion become more sensitive to sound after an acute stress task. This novel finding highlights the importance of including emotional exhaustion in the diagnosis and treatment of hearing problems.

  18. Acute stress differentially affects spatial configuration learning in high and low cortisol-responding healthy adults

    PubMed Central

    Meyer, Thomas; Smeets, Tom; Giesbrecht, Timo; Quaedflieg, Conny W. E. M.; Merckelbach, Harald

    2013-01-01

    Background Stress and stress hormones modulate memory formation in various ways that are relevant to our understanding of stress-related psychopathology, such as posttraumatic stress disorder (PTSD). Particular relevance is attributed to efficient memory formation sustained by the hippocampus and parahippocampus. This process is thought to reduce the occurrence of intrusions and flashbacks following trauma, but may be negatively affected by acute stress. Moreover, recent evidence suggests that the efficiency of visuo-spatial processing and learning based on the hippocampal area is related to PTSD symptoms. Objective The current study investigated the effect of acute stress on spatial configuration learning using a spatial contextual cueing task (SCCT) known to heavily rely on structures in the parahippocampus. Method Acute stress was induced by subjecting participants (N = 34) to the Maastricht Acute Stress Test (MAST). Following a counterbalanced within-subject approach, the effects of stress and the ensuing hormonal (i.e., cortisol) activity on subsequent SCCT performance were compared to SCCT performance following a no-stress control condition. Results Acute stress did not impact SCCT learning overall, but opposing effects emerged for high versus low cortisol responders to the MAST. Learning scores following stress were reduced in low cortisol responders, while high cortisol-responding participants showed improved learning. Conclusions The effects of stress on spatial configuration learning were moderated by the magnitude of endogenous cortisol secretion. These findings suggest a possible mechanism by which cortisol responses serve an adaptive function during stress and trauma, and this may prove to be a promising route for future research in this area. PMID:23671762

  19. Acute psychosocial stress differentially influences salivary endocrine and immune measures in undergraduate students.

    PubMed

    Campisi, Jay; Bravo, Yesika; Cole, Jennifer; Gobeil, Kyle

    2012-10-10

    Undergraduate students routinely experience acute psychosocial stress when interviewing for post-collegiate employment. While numerous studies have demonstrated that acute stress can increase release of immune-relevant molecules in blood, fewer studies have examined if acute stress also increases immune-relevant molecules into saliva. Saliva, and the biomolecules found in saliva often serve important immune defense roles and can be used to non-invasively screen for many systemic diseases. Therefore, the current study examined saliva concentrations of endocrine and immune molecules following exposure to an acute psychosocial stressor (mock job interview) in undergraduates. Heart rate, blood pressure, salivary cortisol, salivary immunoglobulin-A (S-IgA), and salivary C-reactive protein (S-CRP) were compared in healthy college undergraduates (n=15) before and after completion of the Trier Social Stress Test (TSST). The TSST induced significant increases in heart rate, systolic blood pressure, and salivary cortisol. Additional analyses revealed a non-significant (p=0.1) increase in the level of S-IgA following the TSST. A significant decrease in S-IgA was observed during the recovery period. No change in S-CRP was observed following the TSST. These results suggest that acute stress experienced by undergraduates when interviewing for a job activates the sympathetic nervous system and hypothalamic-pituitary-adrenal axis and that cortisol levels increase in saliva. Stress-induced elevations in cortisol might be responsible for the decreased S-IgA observed following the recovery period. Collectively, these data provide further insight into the interaction between psychosocial stress, endocrine, and immune functioning. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Stressful life events and acute kidney injury in intensive and semi-intensive care unities.

    PubMed

    Diniz, Denise Para; Marques, Daniella Aparecida; Blay, Sérgio Luis; Schor, Nestor

    2012-03-01

    Several studies point out that pathophysiological changes related to stress may influence renal function and are associated with disease onset and evolution. However, we have not found any studies about the influence of stress on renal function and acute kidney injury. To evaluate the association between stressful life events and acute kidney injury diagnosis, specifying the most stressful classes of events for these patients in the past 12 months. Case-control study. The study was carried out at Hospital São Paulo, in Universidade Federal de São Paulo and at Hospital dos Servidores do Estado de São Paulo, in Brazil. Patients with acute kidney injury and no chronic disease, admitted to the intensive or semi-intensive care units were included. Controls included patients in the same intensive care units with other acute diseases, except for the acute kidney injury, and also with no chronic disease. Out of the 579 patients initially identified, 475 answered to the Social Readjustment Rating Scale (SRRS) questionnaire and 398 were paired by age and gender (199 cases and 199 controls). The rate of stressful life events was statistically similar between cases and controls. The logistic regression analysis to detect associated effects of the independent variables to the stressful events showed that: increasing age and economic classes A and B in one of the hospitals (Hospital São Paulo - UNIFESP) increased the chance of a stressful life event (SLE). This study did not show association between the Acute Kidney Injury Group with a higher frequency of stressful life events, but that old age, higher income, and type of clinical center were associated.

  1. Acute stress does not impair long-term memory retrieval in older people.

    PubMed

    Pulopulos, Matias M; Almela, Mercedes; Hidalgo, Vanesa; Villada, Carolina; Puig-Perez, Sara; Salvador, Alicia

    2013-09-01

    Previous studies have shown that stress-induced cortisol increases impair memory retrieval in young people. This effect has not been studied in older people; however, some findings suggest that age-related changes in the brain can affect the relationships between acute stress, cortisol and memory in older people. Our aim was to investigate the effects of acute stress on long-term memory retrieval in healthy older people. To this end, 76 participants from 56 to 76 years old (38 men and 38 women) were exposed to an acute psychosocial stressor or a control task. After the stress/control task, the recall of pictures, words and stories learned the previous day was assessed. There were no differences in memory retrieval between the stress and control groups on any of the memory tasks. In addition, stress-induced cortisol response was not associated with memory retrieval. An age-related decrease in cortisol receptors and functional changes in the amygdala and hippocampus could underlie the differences observed between the results from this study and those found in studies performed with young people. Copyright © 2013 Elsevier Inc. All rights reserved.

  2. Acute and chronic stress and the inflammatory response in hyperprolactinemic rats.

    PubMed

    Ochoa-Amaya, J E; Malucelli, B E; Cruz-Casallas, P E; Nasello, A G; Felicio, L F; Carvalho-Freitas, M I R

    2010-01-01

    Prolactin (PRL), a hormone produced by the pituitary gland, has multiple physiological functions, including immunoregulation. PRL can also be secreted in response to stressful stimuli. During stress, PRL has been suggested to oppose the immunosuppressive effects of inflammatory mediators. Therefore, the aim of the present study was to analyze the effects of short- and long-term hyperprolactinemia on the inflammatory response in rats subjected to acute or chronic cold stress. Inflammatory edema was induced by carrageenan in male rats, and hyperprolactinemia was induced by injections of the dopamine receptor antagonist domperidone. The volume of inflammatory edema was measured by plethysmography after carrageenan injection. Additionally, the effects of hyperprolactinemia on body weight and serum corticosterone levels were evaluated. Five days of domperidone-induced hyperprolactinemia increased the volume of inflammatory edema. No differences in serum corticosterone levels were observed between groups. No significant differences were found among 30 days domperidone-induced hyperprolactinemic animals subjected to acute stress and the inflammatory response observed in chronic hyperprolactinemic animals subjected to chronic stress. The results suggest that short-term hyperprolactinemia has pro-inflammatory effects. Because such an effect was not observed in long-term hyperprolactinemic animals, PRL-induced tolerance seems likely. We suggest that short-term hyperprolactinemia may act as a protective factor in rats subjected to acute stress. These data suggest that hyperprolactinemia and stress interact differentially according to the time period. Copyright 2010 S. Karger AG, Basel.

  3. Stress integration after acute and chronic predator stress: differential activation of central stress circuitry and sensitization of the hypothalamo-pituitary-adrenocortical axis.

    PubMed

    Figueiredo, Helmer F; Bodie, Bryan L; Tauchi, Miyuki; Dolgas, C Mark; Herman, James P

    2003-12-01

    Predator exposure is a naturalistic stressor of high ethological relevance. In the current study, our group examined central and peripheral integration of stress responses in rats after acute or repeated exposure to a natural predator (cat). Acute cat exposure rapidly induced hypothalamo-pituitary-adrenocortical (HPA) axis activation and paraventricular nucleus (PVN) CRH mRNA production. Repeated daily cat exposure (7 and 14 d) also up-regulated PVN mRNA CRH expression, but did not result in frank adrenocortical hyperactivity. Unlike other chronic homotypic stress regimens, repeated cat exposure facilitated corticosterone secretion after the 6th or 13th day of exposure. Notably, ACTH secretion and central amygdaloid nucleus CRH mRNA expression were enhanced in animals that were preexposed to the holding chamber relative to chamber-naive rats, suggesting that contextual cues can sensitize subsequent responses to a fearful stimulus. Analysis of c-fos activation was then used to identify brain circuits activated by acute predator stress. Cat exposure elicited a pattern of central c-fos activation that differed substantially from that after either restraint or hypoxia. Predator-specific c-fos mRNA induction was observed in several brain regions comprising the hypothetical brain defense circuit (bed nucleus of the stria terminalis, medial region of the ventromedial nucleus, and dorsal premammillary nucleus). Surprisingly, acute cat exposure did not induce c-fos expression in the PVN. In summary, the data indicate that 1) predation stress invokes a unique stress circuitry that promotes homotypic sensitization of the HPA axis, and 2) familiarization of animals to testing environments can prime central stress pathways to respond robustly to novel threats.

  4. Triathletes Lose Their Advantageous Pain Modulation under Acute Psychosocial Stress.

    PubMed

    Geva, Nirit; Pruessner, Jens; Defrin, Ruth

    2017-02-01

    Triathletes, who constantly engage in intensely stressful sport, were recently found to exhibit greater pain tolerance and more efficient pain inhibition capabilities than nonathletes. However, pain inhibition correlated negatively with retrospective reports of mental stress during training and competition. The aim of the current study was to test pain inhibition capabilities of triathletes under acute, controlled psychological stress manipulation. Participants were 25 triathletes and ironman triathletes who underwent the measurement of pain threshold, pain intolerance, tonic suprathreshold pain, and conditioned pain modulation before and during exposure to the Montreal Imaging Stress Task (MIST). Perceived ratings of stress and anxiety, autonomic variables, and salivary cortisol levels were obtained as indices of stress. The MIST induced a significant stress reaction manifested in the subjective and objective indices. Overall, a significant reduction in pain threshold and in conditioned pain modulation efficacy was observed after the MIST, which reached the baseline levels observed previously in nonathletes. Paradoxically, the magnitude of this stress-induced hyperalgesia (SIH) correlated negatively with the magnitude of the stress response; low-stress responders exhibited greater SIH than high-stress responders. The results suggest that under acute psychological stress, triathletes not only react with SIH and a reduction in pain modulation but also lose their advantageous pain modulation over nonathletes. The stronger the stress response recorded, the weaker the SIH. It appears that triathletes are not resilient to stress, responding with an increase in the sensitivity to pain as well as a decrease in pain inhibition. The possible effects of athletes' baseline pain profile and stress reactivity on SIH are discussed.

  5. Having your cake and eating it too: a habit of comfort food may link chronic social stress exposure and acute stress-induced cortisol hyporesponsiveness.

    PubMed

    Tryon, M S; DeCant, Rashel; Laugero, K D

    2013-04-10

    Stress has been tied to changes in eating behavior and food choice. Previous studies in rodents have shown that chronic stress increases palatable food intake which, in turn, increases visceral fat and inhibits acute stress-induced hypothalamic-pituitary-adrenal (HPA) axis activity. The effect of chronic stress on eating behavior in humans is less understood, but it may be linked to HPA responsivity. The purpose of this study was to investigate the influence of chronic social stress and acute stress reactivity on food choice and food intake. Forty-one women (BMI=25.9±5.1 kg/m(2), age range=41 to 52 years) were subjected to the Trier Social Stress Test or a control task (nature movie) to examine HPA responses to an acute laboratory stressor and then invited to eat from a buffet containing low- and high-calorie snacks. Women were also categorized as high chronic stress or low chronic stress based on Wheaton Chronic Stress Inventory scores. Women reporting higher chronic stress and exhibiting low cortisol reactivity to the acute stress task consumed significantly more calories from chocolate cake on both stress and control visits. Chronic stress in the low cortisol reactor group was also positively related to total fat mass, body fat percentage, and stress-induced negative mood. Further, women reporting high chronic stress consumed significantly less vegetables, but only in those aged 45 years and older. Chronic stress in women within the higher age category was positively related to total calories consumed at the buffet, stress-induced negative mood and food craving. Our results suggest an increased risk for stress eating in persons with a specific chronic stress signature and imply that a habit of comfort food may link chronic social stress and acute stress-induced cortisol hyporesponsiveness. Published by Elsevier Inc.

  6. Reversible inactivation of rostral nucleus raphe pallidus attenuates acute autonomic responses but not their habituation to repeated audiogenic stress in rats.

    PubMed

    Nyhuis, Tara J; Masini, Cher V; Taufer, Kirsten L; Day, Heidi E W; Campeau, Serge

    2016-01-01

    The medullary nucleus raphe pallidus (RPa) mediates several autonomic responses evoked by acute stress exposure, including tachycardia and hyperthermia. The present study assessed whether the RPa contributes to the decline/habituation of these responses observed during repeated audiogenic stress. Adult male rats were implanted with cannulae aimed at the RPa, and abdominal E-mitters that wirelessly acquire heart rate and core body temperature. After surgical recovery, animals were injected with muscimol or vehicle (aCSF) in the RPa region, followed by 30 min of 95-dBA loud noise or no noise control exposures on 3 consecutive days at 24-h intervals. Forty-eight hours after the third exposure, animals were exposed to an additional, but injection-free, loud noise or no noise test to assess habituation of hyperthermia and tachycardia. Three days later, rats were restrained for 30-min to evaluate their ability to display normal acute autonomic responses following the repeated muscimol injection regimen. The results indicated that the inhibition of cellular activity induced by the GABAA-receptor agonist muscimol centered in the RPa region reliably attenuated acute audiogenic stress-evoked tachycardia and hyperthermia, compared with vehicle-injected rats. Animals in the stress groups exhibited similar attenuated tachycardia and hyperthermia during the injection-free fourth audiogenic stress exposure, and displayed similar and robust increases in these responses to the subsequent restraint test. These results suggest that cellular activity in neurons of the RPa region is necessary for the expression of acute audiogenic stress-induced tachycardia and hyperthermia, but may not be necessary for the acquisition of habituated tachycardic responses to repeated stress.

  7. Reversible inactivation of rostral nucleus raphe pallidus attenuates acute autonomic responses but not their habituation to repeated audiogenic stress in rats

    PubMed Central

    Nyhuis, Tara J.; Masini, Cher V.; Taufer, Kirsten L.; Day, Heidi E.W.; Campeau, Serge

    2016-01-01

    The medullary nucleus raphe pallidus (RPa) mediates several autonomic responses evoked by acute stress exposure, including tachycardia and hyperthermia. The present study assessed whether the RPa contributes to the decline/habituation of these responses observed during repeated audiogenic stress. Adult male rats were implanted with cannulae aimed at the RPa, and abdominal E-mitters that wirelessly acquire heart rate and core body temperature. After surgical recovery, animals were injected with muscimol or vehicle (aCSF) in the RPa region, followed by 30 minutes of 95-dBA loud noise or no noise control exposures on 3 consecutive days at 24-hr intervals. Forty-eight hours after the third exposure, animals were exposed to an additional, but injection-free, loud noise or no noise test to assess habituation of hyperthermia and tachycardia. Three days later, rats were restrained for 30-minutes to evaluate their ability to display normal acute autonomic responses following the repeated muscimol injection regimen. The results indicated that the inhibition of cellular activity induced by the GABAA-receptor agonist muscimol centered in the RPa region reliably attenuated acute audiogenic stress-evoked tachycardia and hyperthermia, compared with vehicle-injected rats. Animals in the stress groups exhibited similarly attenuated tachycardia and hyperthermia during the injection-free fourth audiogenic stress exposure, and displayed similar and robust increases in these responses to the subsequent restraint test. These results suggest that cellular activity in neurons of the RPa region is necessary for the expression of acute audiogenic stress-induced tachycardia and hyperthermia, but may not be necessary for the acquisition of habituated tachycardic responses to repeated stress. PMID:26998558

  8. History of chronic stress modifies acute stress-evoked fear memory and acoustic startle in male rats.

    PubMed

    Schmeltzer, Sarah N; Vollmer, Lauren L; Rush, Jennifer E; Weinert, Mychal; Dolgas, Charles M; Sah, Renu

    2015-01-01

    Chronicity of trauma exposure plays an important role in the pathophysiology of posttraumatic stress disorder (PTSD). Thus, exposure to multiple traumas on a chronic scale leads to worse outcomes than acute events. The rationale for the current study was to investigate the effects of a single adverse event versus the same event on a background of chronic stress. We hypothesized that a history of chronic stress would lead to worse behavioral outcomes than a single event alone. Male rats (n = 14/group) were exposed to either a single traumatic event in the form of electric foot shocks (acute shock, AS), or to footshocks on a background of chronic stress (chronic variable stress-shock, CVS-S). PTSD-relevant behaviors (fear memory and acoustic startle responses) were measured following 7 d recovery. In line with our hypothesis, CVS-S elicited significant increases in fear acquisition and conditioning versus the AS group. Unexpectedly, CVS-S elicited reduced startle reactivity to an acoustic stimulus in comparison with the AS group. Significant increase in FosB/ΔFosB-like immunostaining was observed in the dentate gyrus, basolateral amygdala and medial prefrontal cortex of CVS-S rats. Assessments of neuropeptide Y (NPY), a stress-regulatory transmitter associated with chronic PTSD, revealed selective reduction in the hippocampus of CVS-S rats. Collectively, our data show that cumulative stress potentiates delayed fear memory and impacts defensive responding. Altered neuronal activation in forebrain limbic regions and reduced NPY may contribute to these phenomena. Our preclinical studies support clinical findings reporting worse PTSD outcomes stemming from cumulative traumatization in contrast to acute trauma.

  9. The association between acute mental stress and abnormal left atrial electrophysiology.

    PubMed

    O'Neal, Wesley T; Hammadah, Muhammad; Sandesara, Pratik B; Almuwaqqat, Zakaria; Samman-Tahhan, Ayman; Gafeer, Mohamad M; Abdelhadi, Naser; Wilmot, Kobina; Al Mheid, Ibhar; Bremner, Douglas J; Kutner, Michael; Soliman, Elsayed Z; Shah, Amit J; Quyyumi, Arshed A; Vaccarino, Viola

    2017-10-01

    Acute stress may trigger atrial fibrillation (AF), but the underlying mechanisms are unclear. We examined if acute mental stress results in abnormal left atrial electrophysiology as detected by more negative deflection of P-wave terminal force in lead V 1 (PTFV 1 ), a well-known marker of AF risk. We examined this hypothesis in 422 patients (mean age = 56 ± 10 years; 61% men; 44% white) with stable coronary heart disease who underwent mental (speech task) stress testing. PTFV 1 was defined as the duration (milliseconds) times the value of the depth (μV) of the downward deflection (terminal portion) of the P-wave in lead V 1 measured on digital electrocardiograms (ECG). Electrocardiographic left atrial abnormality was defined as PTFV 1 ≤ -4000 μV*ms. Mean PTFV 1 values during stress and recovery were compared with rest. The percentage of participants who developed left atrial abnormality during stress and recovery was compared with the percentage at rest. Compared with rest, PTFV 1 became more negative during mental stress (mean change =  -348, 95% CI = [-515, -182]; P < 0.001) and no change was observed at recovery (mean change = 12, 95%CI = [-148, 172]; P = 0.89). A larger percentage of participants showed left atrial abnormality on ECGs obtained at stress (n = 163, 39%) and recovery (n = 142, 34%) compared with rest (n = 127, 30%). Acute mental stress alters left atrial electrophysiology, suggesting that stressful situations promote adverse transient electrical changes to provide the necessary substrate for AF. © 2017 Wiley Periodicals, Inc.

  10. Hypothalamic-Pituitary-Adrenal Reactivity to Acute Stress: an Investigation into the Roles of Perceived Stress and Family Resources.

    PubMed

    Obasi, Ezemenari M; Shirtcliff, Elizabeth A; Cavanagh, Lucia; Ratliff, Kristen L; Pittman, Delishia M; Brooks, Jessica J

    2017-11-01

    Rurally situated African Americans suffer from chronic exposure to stress that may have a deleterious effect on health outcomes. Unfortunately, research on potential mechanisms that underlie health disparities affecting the African American community has received limited focus in the scientific literature. This study investigated the relationship between perceived stress, family resources, and cortisol reactivity to acute stress. A rural sample of African American emerging adults (N = 60) completed a battery of assessments, the Trier Social Stress Test (TSST), and provided four samples of salivary cortisol: prior to receiving TSST instructions, prior to conducting the speech task, immediately following the TSST, and 15-20 min following the TSST. As predicted, cortisol levels increased in response to a controlled laboratory inducement of acute stress. Moreover, diminished levels of family resources were associated with blunted cortisol reactivity to acute stress. Of note, higher levels of perceived stress over the past month and being male were independently associated with lower levels of cortisol at baseline. Lack of family resources had a blunting relationship on the hypothalamic-pituitary-adrenal axis reactivity. These findings provide biomarker support for the relationship between family resources-an indicator associated with social determinants of health-and stress physiology within a controlled laboratory experiment. Identifying mechanisms that work toward explanation of within-group differences in African American health disparities is both needed and informative for culturally informed prevention and intervention efforts.

  11. Different effects of acute and chronic immobilization stress on plasma testosterone levels in male Syrian hamsters.

    PubMed

    Tsuchiya, T; Horii, I

    1995-01-01

    Time-course variations in plasma testosterone levels after various periods of immobilization stress (10 min, 30 min, 2 h, 6 h) were examined in male Syrian hamsters. The immobilization stress consisted of placing the animals in a prone position and wrapping them with flexible steel wire gauze. This was done at room temperature. Testosterone levels were determined in blood samples taken after the hamsters were decapitated. Chronic (2 h, 6 h) immobilization stress produced a drastic and enduring fall in plasma testosterone levels. Reduction of plasma testosterone following the 6-h immobilization stress was observed even 18 h after the stress had been relieved. However, acute (10 min, 30 min) immobilization stress did not influence plasma testosterone. These findings indicated that the effect of immobilization stress on plasma testosterone in hamsters was not biphasic, which it is in rats. Further, these results suggest that immobilization stress in hamsters would be a valuable technique with which to investigate the effects of physiological ranges of testosterone on physiological and psychological functions.

  12. Olive oil-supplemented diet alleviates acute heat stress-induced mitochondrial ROS production in chicken skeletal muscle.

    PubMed

    Mujahid, Ahmad; Akiba, Yukio; Toyomizu, Masaaki

    2009-09-01

    We have previously shown that avian uncoupling protein (avUCP) is downregulated on exposure to acute heat stress, stimulating mitochondrial reactive oxygen species (ROS) production and oxidative damage. In this study, we investigated whether upregulation of avUCP could attenuate oxidative damage caused by acute heat stress. Broiler chickens (Gallus gallus) were fed either a control diet or an olive oil-supplemented diet (6.7%), which has been shown to increase the expression of UCP3 in mammals, for 8 days and then exposed either to heat stress (34 degrees C, 12 h) or kept at a thermoneutral temperature (25 degrees C). Skeletal muscle mitochondrial ROS (measured as H(2)O(2)) production, avUCP expression, oxidative damage, mitochondrial membrane potential, and oxygen consumption were studied. We confirmed that heat stress increased mitochondrial ROS production and malondialdehyde levels and decreased the amount of avUCP. As expected, feeding birds an olive oil-supplemented diet increased the expression of avUCP in skeletal muscle mitochondria and decreased ROS production and oxidative damage. Studies on mitochondrial function showed that heat stress increased membrane potential in state 4, which was reversed by feeding birds an olive oil-supplemented diet, although no differences in basal proton leak were observed between control and heat-stressed groups. These results show that under heat stress, mitochondrial ROS production and olive oil-induced reduction of ROS production may occur due to changes in respiratory chain activity as well as avUCP expression in skeletal muscle mitochondria.

  13. Time matters - acute stress response and glucocorticoid sensitivity in early multiple sclerosis.

    PubMed

    Kern, Simone; Rohleder, Nicolas; Eisenhofer, Graeme; Lange, Jan; Ziemssen, Tjalf

    2014-10-01

    Psychosocial stress has frequently been associated with disease activity and acute exacerbations in multiple sclerosis (MS). Despite this well established finding, strikingly little is known about the acute hypothalamic-pituitary-adrenal (HPA) and sympathetic-adrenal-medullary (SAM) stress response in MS. Twenty-six early relapsing-remitting MS (RRMS) patients and seventeen age- and sex-matched healthy control subjects (CS) took part in the Trier Social Stress Test (TSST), a well validated psycho-social laboratory stress protocol. Repeated blood samples were analyzed for stress-related cortisol and catecholamine levels as well as for glucocorticoid sensitivity (GCS) of target immune cells. Chronic and acute stress appraisals were assessed by self-report measures. RRMS patients and CS did not differ in stress-related cortisol/catecholamine levels, GCS or stress appraisal in response to the TSST. However, cortisol release as well as GCS was strongly correlated with time since diagnosis but not with neurological disability. Patients with shorter disease duration (2-12 months) expressed a significantly higher cortisol stress response while MS patients with longer disease duration (14-36 months) showed a significantly diminished HPA response as well as lower post-stress GCS. There is evidence for a time-dependent variability in the HPA stress system with an increased cortisol stress response in the first year after diagnosis along with a more blunted HPA stress response and a diminished GCS in subsequent disease stages. Data underscore the highly dynamic nature of HPA axis regulation in the MS disease process, which could possibly relate to compensatory mechanisms within a cytokine-HPA axis feedback circuit model. Copyright © 2014 Elsevier Inc. All rights reserved.

  14. Behavioral and autonomic responses to acute restraint stress are segregated within the lateral septal area of rats.

    PubMed

    Reis, Daniel G; Scopinho, América A; Guimarães, Francisco S; Corrêa, Fernando M A; Resstel, Leonardo B M

    2011-01-01

    The Lateral Septal Area (LSA) is involved with autonomic and behavior responses associated to stress. In rats, acute restraint (RS) is an unavoidable stress situation that causes autonomic (body temperature, mean arterial pressure (MAP) and heart rate (HR) increases) and behavioral (increased anxiety-like behavior) changes in rats. The LSA is one of several brain regions that have been involved in stress responses. The aim of the present study was to investigate if the neurotransmission blockade in the LSA would interfere in the autonomic and behavioral changes induced by RS. Male Wistar rats with bilateral cannulae aimed at the LSA, an intra-abdominal datalogger (for recording internal body temperature), and an implanted catheter into the femoral artery (for recording and cardiovascular parameters) were used. They received bilateral microinjections of the non-selective synapse blocker cobalt chloride (CoCl(2), 1 mM/ 100 nL) or vehicle 10 min before RS session. The tail temperature was measured by an infrared thermal imager during the session. Twenty-four h after the RS session the rats were tested in the elevated plus maze (EPM). Inhibition of LSA neurotransmission reduced the MAP and HR increases observed during RS. However, no changes were observed in the decrease in skin temperature and increase in internal body temperature observed during this period. Also, LSA inhibition did not change the anxiogenic effect induced by RS observed 24 h later in the EPM. The present results suggest that LSA neurotransmission is involved in the cardiovascular but not the temperature and behavioral changes induced by restraint stress.

  15. The influence of acute stress on the regulation of conditioned fear

    PubMed Central

    Raio, Candace M.; Phelps, Elizabeth A.

    2014-01-01

    Fear learning and regulation is a prominent model for describing the pathogenesis of anxiety disorders and stress-related psychopathology. Fear expression can be modulated using a number of regulatory strategies, including extinction, cognitive emotion regulation, avoidance strategies and reconsolidation. In this review, we examine research investigating the effects of acute stress and stress hormones on these regulatory techniques. We focus on what is known about the impact of stress on the ability to flexibly regulate fear responses that are acquired through Pavlovian fear conditioning. Our primary aim is to explore the impact of stress on fear regulation in humans. Given this, we focus on techniques where stress has been linked to alterations of fear regulation in humans (extinction and emotion regulation), and briefly discuss other techniques (avoidance and reconsolidation) where the impact of stress or stress hormones have been mainly explored in animal models. These investigations reveal that acute stress may impair the persistent inhibition of fear, presumably by altering prefrontal cortex function. Characterizing the effects of stress on fear regulation is critical for understanding the boundaries within which existing regulation strategies are viable in everyday life and can better inform treatment options for those who suffer from anxiety and stress-related psychopathology. PMID:25530986

  16. Acute Stress Induces Hyperacusis in Women with High Levels of Emotional Exhaustion

    PubMed Central

    Hasson, Dan; Theorell, Töres; Bergquist, Jonas; Canlon, Barbara

    2013-01-01

    Background Hearing problems is one of the top ten public health disorders in the general population and there is a well-established relationship between stress and hearing problems. The aim of the present study was to explore if an acute stress will increase auditory sensitivity (hyperacusis) in individuals with high levels of emotional exhaustion (EE). Methods Hyperacusis was assessed using uncomfortable loudness levels (ULL) in 348 individuals (140 men; 208 women; age 23–71 years). Multivariate analyses (ordered logistic regression), were used to calculate odds ratios, including interacting or confounding effects of age, gender, ear wax and hearing loss (PTA). Two-way ANCOVAs were used to assess possible differences in mean ULLs between EE groups pre- and post-acute stress task (a combination of cold pressor, emotional Stroop and Social stress/video recording). Results There were no baseline differences in mean ULLs between the three EE groups (one-way ANOVA). However, after the acute stress exposure there were significant differences in ULL means between the EE-groups in women. Post-hoc analyses showed that the differences in mean ULLs were between those with high vs. low EE (range 5.5–6.5 dB). Similar results were found for frequencies 0.5 and 1 kHz. The results demonstrate that women with high EE-levels display hyperacusis after an acute stress task. The odds of having hyperacusis were 2.5 (2 kHz, right ear; left ns) and 2.2 (4 kHz, right ear; left ns) times higher among those with high EE compared to those with low levels. All these results are adjusted for age, hearing loss and ear wax. Conclusion Women with high levels of emotional exhaustion become more sensitive to sound after an acute stress task. This novel finding highlights the importance of including emotional exhaustion in the diagnosis and treatment of hearing problems. PMID:23301005

  17. Increased neural responses to empathy for pain might explain how acute stress increases prosociality

    PubMed Central

    Tomova, L.; Majdandžić, J.; Hummer, A.; Windischberger, C.; Heinrichs, M.

    2017-01-01

    Abstract Recent behavioral investigations suggest that acute stress can increase prosocial behavior. Here, we investigated whether increased empathy represents a potential mechanism for this finding. Using functional magnetic resonance imaging, we assessed the effects of acute stress on neural responses related to automatic and regulatory components of empathy for pain as well as subsequent prosocial behavior. Stress increased activation in brain areas associated with the automatic sharing of others’ pain, such as the anterior insula, the anterior midcingulate cortex, and the primary somatosensory cortex. In addition, we found increased prosocial behavior under stress. Furthermore, activation in the anterior midcingulate cortex mediated the effects of stress on prosocial behavior. However, stressed participants also displayed stronger and inappropriate other-related responses in situations which required them to take the perspective of another person, and to regulate their automatic affective responses. Thus, while acute stress may increase prosocial behavior by intensifying the sharing of others’ emotions, this comes at the cost of reduced cognitive appraisal abilities. Depending on the contextual constraints, stress may therefore affect empathy in ways that are either beneficial or detrimental. PMID:27798249

  18. Acute Stress Disorder as a Predictor of Post-Traumatic Stress Disorder in Physical Assault Victims

    ERIC Educational Resources Information Center

    Elklit, Ask; Brink, Ole

    2004-01-01

    The authors' objective was to examine the ability of acute stress disorder (ASD) and other trauma-related factors in a group of physical assault victims in predicting post-traumatic stress disorder (PTSD) 6 months later. Subjects included 214 victims of violence who completed a questionnaire 1 to 2 weeks after the assault, with 128 participating…

  19. Effects of acute temperature change, confinement and housing on plasma corticosterone in water snakes, Nerodia sipedon (Colubridae: Natricinae).

    PubMed

    Sykes, Kyle Lea; Klukowski, Matthew

    2009-03-01

    Body temperature affects many aspects of reptilian behavior and physiology, but its effect on hormonal secretion has been little studied, especially in snakes. Major objectives of this study were to determine if acute changes in body temperature during confinement influenced plasma corticosterone levels and if initial body temperatures upon capture in the field were related to baseline corticosterone levels in water snakes (Nerodia sipedon). Water snakes were bled upon capture in the field and after one hour of confinement in a cooled, control, or heated incubator. Since little is known about the potential metabolic changes in response to stress in reptiles, plasma triglyceride levels were also measured. Upon completion of the field study, snakes were housed for 5-8 days without food to determine the effect of chronic stress on both corticosterone and triglyceride levels. Plasma corticosterone concentrations were measured using enzyme-linked immunosorbant assay (ELISA) and plasma triglycerides were determined enzymatically. In the field, experimental alterations of body temperature during confinement had no effect on corticosterone levels. Similarly, there was no correlation between initial body temperature and baseline plasma corticosterone concentrations. However, post-confinement corticosterone levels were approximately three-times greater in females than males. Plasma triglyceride levels were not affected by temperature treatment, confinement, or sex. Compared to field values, both baseline and post-confinement corticosterone levels were elevated after the chronic stress of short-term laboratory housing but triglyceride levels decreased. Overall, these results indicate that sex but not body temperature has a major influence on the adrenocortical stress response in Nerodia sipedon.

  20. Traumatic Memories in Acute Stress Disorder: An Analysis of Narratives before and after Treatment

    ERIC Educational Resources Information Center

    Moulds, Michelle L.; Bryant, Richard A.

    2005-01-01

    The dissociative reactions in acute stress disorder purportedly impede encoding and organization of traumatic memories and consequently impair the individual's ability to retrieve trauma-related details. A qualitative examination was conducted on trauma narratives of individuals with acute stress disorder (N = 15) prior to cognitive behavior…

  1. Impact of acute psychological stress on cardiovascular risk factors in face of insulin resistance.

    PubMed

    Jones, Kristian T; Shelton, Richard C; Wan, Jun; Li, Li

    2016-11-01

    Individuals with insulin resistance (IR) are at greater risk for cardiovascular disease (CVD). Psychological stress may contribute to develop CVD in IR, although mechanisms are poorly understood. Our aim was to test the hypothesis that individuals with IR have enhanced emotional and physiological responses to acute psychological stress, leading to increased CVD risk. Sixty participants were enrolled into the study, and classified into IR group (n = 31) and insulin sensitive group (n = 29) according to the Quantitative insulin sensitivity check index, which was calculated based on an oral glucose tolerance test. The Trier social stress test, a standardized experimental stress paradigm, was performed on each participant, and emotional and physiological responses were examined. Blood was collected from each subject for insulin, cytokines, and cortisol measurements. Compared with the insulin-sensitive group, individuals with IR had significantly lower ratings of energy and calm, but higher fatigue levels in response to acute stressors. Individuals with IR also showed blunted heart rate reactivity following stress. In addition, the IR status was worsened by acute psychological stress as demonstrated by further increased insulin secretion. Furthermore, individuals with IR showed significantly increased levels of leptin and interleukin-6, but decreased levels of adiponectin, at baseline, stress test, and post-stress period. Our findings in individuals with IR under acute stress would allow a better understanding of the risks for developing CVD and to tailor the interventions for better outcomes.

  2. Impact of Acute Psychological Stress on Cardiovascular Risk Factors in Face of Insulin Resistance

    PubMed Central

    Jones, Kristian T.; Shelton, Richard C.; Wan, Jun; Li, Li

    2016-01-01

    Individuals with insulin resistance (IR) are at greater risk for cardiovascular disease (CVD). Psychological stress may contribute to develop CVD in IR although mechanisms are poorly understood. Our aim was to test the hypothesis that individuals with IR have enhanced emotional and physiological responses to acute psychological stress, leading to increased CVD risk. Sixty participants were enrolled into the study, and classified into IR group (n=31) and insulin sensitive group (n=29) according to the Quantitative insulin sensitivity check index, which was calculated based on an oral glucose tolerance test. The Trier social stress test, a standardized experimental stress paradigm, was performed on each participant, and emotional and physiological responses were examined. Blood was collected from each subject for insulin, cytokines and cortisol measurements. Compared with insulin sensitive group, individuals with IR had significantly lower ratings of energy and calm, but higher fatigue levels in response to acute stressors. Individuals with IR also showed blunted heart rate reactivity following stress. In addition, the IR status was worsened by acute psychological stress as demonstrated by further increased insulin secretion. Furthermore, individuals with IR showed significantly increased levels of leptin and interleukin-6, but decreased levels of adiponectin, at baseline, stress test and post-stress period. Our findings in individuals with IR under acute stress would allow a better understanding of the risks for developing CVD and to tailor the interventions for better outcomes. PMID:27588343

  3. Acute stress negatively affects object recognition early memory consolidation and memory retrieval unrelated to state-dependency.

    PubMed

    Nelissen, Ellis; Prickaerts, Jos; Blokland, Arjan

    2018-06-01

    It is well known that stress affects memory performance. However, there still appears to be inconstancy in literature about how acute stress affects the different stages of memory: acquisition, consolidation and retrieval. In this study, we exposed rats to acute stress and measured the effect on memory performance in the object recognition task as a measure for episodic memory. Stress was induced 30 min prior to the learning phase to affect acquisition, directly after the learning phase to affect consolidation, or 30 min before the retrieval phase to affect retrieval. Additionally, we induced stress both 30 min prior to the learning phase and 30 min prior to the retrieval phase to test whether the effects were related to state-dependency. As expected, we found that acute stress did not affect acquisition but had a negative impact on retrieval. To our knowledge, we are the first to show that early consolidation was negatively affected by acute stress. We also show that stress does not have a state-dependent effect on memory. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Acute normobaric hypoxia reduces body temperature in humans.

    PubMed

    DiPasquale, Dana M; Kolkhorst, Fred W; Buono, Michael J

    2015-03-01

    Anapyrexia is the regulated decrease in body temperature during acute exposure to hypoxia. This study examined resting rectal temperature (Trec) in adult humans during acute normobaric hypoxia (NH). Ten subjects breathed air consisting of 21% (NN), 14% (NH14), and 12% oxygen (NH12) for 30 min each in thermoneutral conditions while Trec and blood oxygen saturation (Spo2) were measured. Linear regression indicated that Spo2 was progressively lower in NH14 (p=0.0001) and NH12 (p=0.0001) compared to NN, and that Spo2 in NH14 was different than NH12 (p=0.00001). Trec was progressively lower during NH14 (p=0.014) and in NH12 (p=0.0001) compared to NN. The difference in Trec between NH14 and NH12 was also significant (p=0.0287). Spo2 was a significant predictor of Trec such that for every 1% decrease in Spo2, Trec decreased by 0.15°C (p=0.0001). The present study confirmed that, similar to many other species, human adults respond to acute hypoxia exposure by lowering rectal temperature.

  5. Acute stress switches spatial navigation strategy from egocentric to allocentric in a virtual Morris water maze.

    PubMed

    van Gerven, Dustin J H; Ferguson, Thomas; Skelton, Ronald W

    2016-07-01

    Stress and stress hormones are known to influence the function of the hippocampus, a brain structure critical for cognitive-map-based, allocentric spatial navigation. The caudate nucleus, a brain structure critical for stimulus-response-based, egocentric navigation, is not as sensitive to stress. Evidence for this comes from rodent studies, which show that acute stress or stress hormones impair allocentric, but not egocentric navigation. However, there have been few studies investigating the effect of acute stress on human spatial navigation, and the results of these have been equivocal. To date, no study has investigated whether acute stress can shift human navigational strategy selection between allocentric and egocentric navigation. The present study investigated this question by exposing participants to an acute psychological stressor (the Paced Auditory Serial Addition Task, PASAT), before testing navigational strategy selection in the Dual-Strategy Maze, a modified virtual Morris water maze. In the Dual-Strategy maze, participants can chose to navigate using a constellation of extra-maze cues (allocentrically) or using a single cue proximal to the goal platform (egocentrically). Surprisingly, PASAT stress biased participants to solve the maze allocentrically significantly more, rather than less, often. These findings have implications for understanding the effects of acute stress on cognitive function in general, and the function of the hippocampus in particular. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. The effect of obesity on inflammatory cytokine and leptin production following acute mental stress.

    PubMed

    Caslin, H L; Franco, R L; Crabb, E B; Huang, C J; Bowen, M K; Acevedo, E O

    2016-02-01

    Obesity may contribute to cardiovascular disease (CVD) risk by eliciting chronic systemic inflammation and impairing the immune response to additional stressors. There has been little assessment of the effect of obesity on psychological stress, an independent risk factor for CVD. Therefore, it was of interest to examine interleukin-6, tumor necrosis factor-α, interleukin-1β (IL-1β), interleukin-1 receptor antagonist (IL-1Ra), and leptin following an acute mental stress task in nonobese and obese males. Twenty college-aged males (21.3 ± 0.56 years) volunteered to participate in a 20-min Stroop color-word and mirror-tracing task. Subjects were recruited for obese (body mass index: BMI > 30) and nonobese (BMI < 25) groups, and blood samples were collected for enzyme-linked immunosorbent assay analysis. The acute mental stress task elicited an increase in heart rate, catecholamines, and IL-1β in all subjects. Additionally, acute mental stress increased cortisol concentrations in the nonobese group. There was a significant reduction in leptin in obese subjects 30 min posttask compared with a decrease in nonobese subjects 120 min posttask. Interestingly, the relationship between the percent change in leptin and IL-1Ra at 120 min posttask in response to an acute mental stress task was only observed in nonobese individuals. This is the first study to suggest that adiposity in males may impact leptin and inflammatory signaling mechanisms following acute mental stress. © 2015 Society for Psychophysiological Research.

  7. Yeast Hog1 proteins are sequestered in stress granules during high-temperature stress.

    PubMed

    Shiraishi, Kosuke; Hioki, Takahiro; Habata, Akari; Yurimoto, Hiroya; Sakai, Yasuyoshi

    2018-01-09

    The yeast high-osmolarity glycerol (HOG) pathway plays a central role in stress responses. It is activated by various stresses, including hyperosmotic stress, oxidative stress, high-temperature stress and exposure to arsenite. Hog1, the crucial MAP kinase of the pathway, localizes to the nucleus in response to high osmotic concentrations, i.e. high osmolarity; but, otherwise, little is known about its intracellular dynamics and regulation. By using the methylotrophic yeast Candida boidinii , we found that CbHog1-Venus formed intracellular dot structures after high-temperature stress in a reversible manner. Microscopic observation revealed that CbHog1-mCherry colocalized with CbPab1-Venus, a marker protein of stress granules. Hog1 homologs in Pichia pastoris and Schizosaccharomyces pombe also exhibited similar dot formation under high-temperature stress, whereas Saccharomyces cerevisiae Hog1 (ScHog1)-GFP did not. Analysis of CbHog1-Venus in C. boidinii revealed that a β-sheet structure in the N-terminal region was necessary and sufficient for its localization to stress granules. Physiological studies revealed that sequestration of activated Hog1 proteins in stress granules was responsible for downregulation of Hog1 activity under high-temperature stress.This article has an associated First Person interview with the first author of the paper. © 2018. Published by The Company of Biologists Ltd.

  8. Acute stress disorder as a predictor of posttraumatic stress: A longitudinal study of Chinese children exposed to the Lushan earthquake.

    PubMed

    Zhou, Peiling; Zhang, Yuqing; Wei, Chuguang; Liu, Zhengkui; Hannak, Walter

    2016-09-01

    This study examined the prevalence of acute stress disorder (ASD) and posttraumatic stress disorder (PTSD) in children who experienced the Lushan earthquake in Sichuan, China, and assessed the ability of ASD to predict PTSD. The Acute Stress Disorder Scale (ASDS) was used to assess acute stress reaction within weeks of the trauma. The University of California at Los Angeles Post-Traumatic Stress Disorder Reaction Index (UCLA-PTSD) for children was administered at intervals of 2, 6, and 12 months after the earthquake to 197 students who experienced the Lushan earthquake at the Longxing Middle School. The results demonstrated that 28.4% of the children suffered from ASD, but only a small percentage of the population went on to develop PTSD. Among all of the students, 35.0% of those who met the criteria for ASD were diagnosed with PTSD at the 12-month interval. The severity of ASD symptoms correlated with later PTSD symptoms. © 2016 The Institute of Psychology, Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  9. Psychogenic fever: how psychological stress affects body temperature in the clinical population

    PubMed Central

    Oka, Takakazu

    2015-01-01

    Psychogenic fever is a stress-related, psychosomatic disease especially seen in young women. Some patients develop extremely high core body temperature (Tc) (up to 41°C) when they are exposed to emotional events, whereas others show persistent low-grade high Tc (37–38°C) during situations of chronic stress. The mechanism for psychogenic fever is not yet fully understood. However, clinical case reports demonstrate that psychogenic fever is not attenuated by antipyretic drugs, but by psychotropic drugs that display anxiolytic and sedative properties, or by resolving patients' difficulties via natural means or psychotherapy. Animal studies have demonstrated that psychological stress increases Tc via mechanisms distinct from infectious fever (which requires proinflammatory mediators) and that the sympathetic nervous system, particularly β3-adrenoceptor-mediated non-shivering thermogenesis in brown adipose tissue, plays an important role in the development of psychological stress-induced hyperthermia. Acute psychological stress induces a transient, monophasic increase in Tc. In contrast, repeated stress induces anticipatory hyperthermia, reduces diurnal changes in Tc, or slightly increases Tc throughout the day. Chronically stressed animals also display an enhanced hyperthermic response to a novel stress, while past fearful experiences induce conditioned hyperthermia to the fear context. The high Tc that psychogenic fever patients develop may be a complex of these diverse kinds of hyperthermic responses. PMID:27227051

  10. Psychogenic fever: how psychological stress affects body temperature in the clinical population.

    PubMed

    Oka, Takakazu

    2015-01-01

    Psychogenic fever is a stress-related, psychosomatic disease especially seen in young women. Some patients develop extremely high core body temperature (Tc) (up to 41°C) when they are exposed to emotional events, whereas others show persistent low-grade high Tc (37-38°C) during situations of chronic stress. The mechanism for psychogenic fever is not yet fully understood. However, clinical case reports demonstrate that psychogenic fever is not attenuated by antipyretic drugs, but by psychotropic drugs that display anxiolytic and sedative properties, or by resolving patients' difficulties via natural means or psychotherapy. Animal studies have demonstrated that psychological stress increases Tc via mechanisms distinct from infectious fever (which requires proinflammatory mediators) and that the sympathetic nervous system, particularly β3-adrenoceptor-mediated non-shivering thermogenesis in brown adipose tissue, plays an important role in the development of psychological stress-induced hyperthermia. Acute psychological stress induces a transient, monophasic increase in Tc. In contrast, repeated stress induces anticipatory hyperthermia, reduces diurnal changes in Tc, or slightly increases Tc throughout the day. Chronically stressed animals also display an enhanced hyperthermic response to a novel stress, while past fearful experiences induce conditioned hyperthermia to the fear context. The high Tc that psychogenic fever patients develop may be a complex of these diverse kinds of hyperthermic responses.

  11. The Effects of Acute Stress on Core Executive Functions: A Meta-Analysis and Comparison with Cortisol

    PubMed Central

    Shields, Grant S.; Sazma, Matthew A.; Yonelinas, Andrew P.

    2016-01-01

    Core executive functions such as working memory, inhibition, and cognitive flexibility are integral to daily life. A growing body of research has suggested that acute stress may impair core executive functions. However, there are a number of inconsistencies in the literature, leading to uncertainty about how or even if acute stress influences core executive functions. We addressed this by conducting a meta-analysis of acute stress effects on working memory, inhibition, and cognitive flexibility. We found that stress impaired working memory and cognitive flexibility, whereas it had nuanced effects on inhibition. Many of these effects were moderated by other variables, such as sex. In addition, we compared effects of acute stress on core executive functions to effects of cortisol administration and found some striking differences. Our findings indicate that stress works through mechanisms aside from or in addition to cortisol to produce a state characterized by more reactive processing of salient stimuli but greater control over actions. We conclude by highlighting some important future directions for stress and executive function research. PMID:27371161

  12. Increased neural responses to empathy for pain might explain how acute stress increases prosociality.

    PubMed

    Tomova, L; Majdandžic, J; Hummer, A; Windischberger, C; Heinrichs, M; Lamm, C

    2017-03-01

    Recent behavioral investigations suggest that acute stress can increase prosocial behavior. Here, we investigated whether increased empathy represents a potential mechanism for this finding. Using functional magnetic resonance imaging, we assessed the effects of acute stress on neural responses related to automatic and regulatory components of empathy for pain as well as subsequent prosocial behavior. Stress increased activation in brain areas associated with the automatic sharing of others' pain, such as the anterior insula, the anterior midcingulate cortex, and the primary somatosensory cortex. In addition, we found increased prosocial behavior under stress. Furthermore, activation in the anterior midcingulate cortex mediated the effects of stress on prosocial behavior. However, stressed participants also displayed stronger and inappropriate other-related responses in situations which required them to take the perspective of another person, and to regulate their automatic affective responses. Thus, while acute stress may increase prosocial behavior by intensifying the sharing of others' emotions, this comes at the cost of reduced cognitive appraisal abilities. Depending on the contextual constraints, stress may therefore affect empathy in ways that are either beneficial or detrimental. © The Author (2016). Published by Oxford University Press.

  13. Dynamic changes in DNA methylation of stress-associated genes (OXTR, BDNF ) after acute psychosocial stress.

    PubMed

    Unternaehrer, E; Luers, P; Mill, J; Dempster, E; Meyer, A H; Staehli, S; Lieb, R; Hellhammer, D H; Meinlschmidt, G

    2012-08-14

    Environmentally induced epigenetic alterations are related to mental health. We investigated quantitative DNA methylation status before and after an acute psychosocial stressor in two stress-related genes: oxytocin receptor (OXTR) and brain-derived neurotrophic factor (BDNF ). The cross sectional study took place at the Division of Theoretical and Clinical Psychobiology, University of Trier, Germany and was conducted from February to August 2009. We included 83 participants aged 61-67 years. Thereof, 76 participants completed the full study procedure consisting of blood sampling before (pre-stress), 10 min after (post-stress) and 90 min after (follow-up) the Trier social stress test. We assessed quantitative DNA methylation of whole-blood cells using Sequenom EpiTYPER. Methylation status differed between sampling times in one target sequence of OXTR (P<0.001): methylation increased from pre- to post-stress (P=0.009) and decreased from post-stress to follow-up (P<0.001). This decrease was also found in a second target sequence of OXTR (P=0.034), where it lost statistical significance when blood cell count was statistically controlled. We did not detect any time-associated differences in methylation status of the examined BDNF region. The results suggest a dynamic regulation of DNA methylation in OXTR-which may in part reflect changes in blood cell composition-but not BDNF after acute psychosocial stress. This may enhance the understanding of how psychosocial events alter DNA methylation and could provide new insights into the etiology of mental disorders.

  14. Chronic and acute effects of stress on energy balance: are there appropriate animal models?

    PubMed

    Harris, Ruth B S

    2015-02-15

    Stress activates multiple neural and endocrine systems to allow an animal to respond to and survive in a threatening environment. The corticotropin-releasing factor system is a primary initiator of this integrated response, which includes activation of the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis. The energetic response to acute stress is determined by the nature and severity of the stressor, but a typical response to an acute stressor is inhibition of food intake, increased heat production, and increased activity with sustained changes in body weight, behavior, and HPA reactivity. The effect of chronic psychological stress is more variable. In humans, chronic stress may cause weight gain in restrained eaters who show increased HPA reactivity to acute stress. This phenotype is difficult to replicate in rodent models where chronic psychological stress is more likely to cause weight loss than weight gain. An exception may be hamsters subjected to repeated bouts of social defeat or foot shock, but the data are limited. Recent reports on the food intake and body composition of subordinate members of group-housed female monkeys indicate that these animals have a similar phenotype to human stress-induced eaters, but there are a limited number of investigators with access to the model. Few stress experiments focus on energy balance, but more information on the phenotype of both humans and animal models during and after exposure to acute or chronic stress may provide novel insight into mechanisms that normally control body weight. Copyright © 2015 the American Physiological Society.

  15. Chronic and acute effects of stress on energy balance: are there appropriate animal models?

    PubMed Central

    2014-01-01

    Stress activates multiple neural and endocrine systems to allow an animal to respond to and survive in a threatening environment. The corticotropin-releasing factor system is a primary initiator of this integrated response, which includes activation of the sympathetic nervous system and the hypothalamic-pituitary-adrenal (HPA) axis. The energetic response to acute stress is determined by the nature and severity of the stressor, but a typical response to an acute stressor is inhibition of food intake, increased heat production, and increased activity with sustained changes in body weight, behavior, and HPA reactivity. The effect of chronic psychological stress is more variable. In humans, chronic stress may cause weight gain in restrained eaters who show increased HPA reactivity to acute stress. This phenotype is difficult to replicate in rodent models where chronic psychological stress is more likely to cause weight loss than weight gain. An exception may be hamsters subjected to repeated bouts of social defeat or foot shock, but the data are limited. Recent reports on the food intake and body composition of subordinate members of group-housed female monkeys indicate that these animals have a similar phenotype to human stress-induced eaters, but there are a limited number of investigators with access to the model. Few stress experiments focus on energy balance, but more information on the phenotype of both humans and animal models during and after exposure to acute or chronic stress may provide novel insight into mechanisms that normally control body weight. PMID:25519732

  16. Effects of different acute high ambient temperatures on function of hepatic mitochondrial respiration, antioxidative enzymes, and oxidative injury in broiler chickens.

    PubMed

    Tan, G-Y; Yang, L; Fu, Y-Q; Feng, J-H; Zhang, M-H

    2010-01-01

    This study investigated the effects of different acute high ambient temperatures on dysfunction of hepatic mitochondrial respiration, the antioxidative enzyme system, and oxidative injury in broiler chickens. One hundred twenty-eight 6-wk-old broiler chickens were assigned randomly to 4 groups and subsequently exposed to 25 (control), 32, 35, and 38 degrees C (RH, 70 +/- 5%) for 3 h, respectively. The rectal temperatures, activity of antioxidative enzymes (superoxide dismutase, catalase, and glutathione peroxidase), content of malondialdehyde and protein carbonyl, and the activity of mitochondrial respiratory enzymes were determined. The results showed that exposure to high ambient temperature induced a significant elevation of rectal temperature, antioxidative enzyme activity, and formation of malondialdehyde and protein carbonyl, as well as dysfunction of the mitochondrial respiratory chain in comparison with control (P < 0.05). Almost all of the indicators changed in a temperature-dependent manner with the gradual increase of ambient temperature from 32 to 38 degrees C; differences in each parameter (except catalase) among the groups exposed to different high ambient temperatures were also statistically significant (P < 0.05). The results of the present study suggest that, in the broiler chicken model used here, acute exposure to high temperatures may depress the activity of the mitochondrial respiratory chain. This inactivation results subsequently in overproduction of reactive oxygen species, which ultimately results in oxidative injury. However, this hypothesis needs to be evaluated more rigorously in future studies. It has also been shown that, with the gradual increase in temperature, the oxidative injury induced by heat stress in broiler chickens becomes increasingly severe, and this stress response presents in a temperature-dependent manner in the temperature range of 32 to 38 degrees C.

  17. Acute stress among adolescents and female rape victims measured by ASC-Kids: a pilot study.

    PubMed

    Nilsson, Doris; Nordenstam, Carin; Green, Sara; Wetterhall, Annika; Lundin, Tom; Svedin, Carl Göran

    2015-01-01

    Rape is considered a stressful trauma and often with durable consequences. How the aftermath of rape is for young adolescents' girls considering acute stress is an overlooked field and remains to be studied. In this study, we wanted to investigate acute stress among adolescent victims of rape and the psychometric properties of the Acute Stress Checklist for Children (ASC-Kids). A clinical sample (n = 79) of raped girls, 13-17 years old who had turned to a special rape victim unit for treatment, answered the ASC-Kids. ASC-Kids was also given to a group of minor stressed, non-raped adolescents in the same age range (n = 154) together with the University of California at Los Angeles Post-traumatic Stress Disorder Reaction Index (UCLA PTSD RI), and the Sense of Coherence Scale 13 (SOC-13). The scores from the groups were compared and showed significant differences in mean values on all the diagnostic criteria of acute stress disorder. In the clinical group, 36.7% obtained full ASD criteria. ASC-Kids could discriminate well between groups. Cronbach's alpha was found to be excellent, and the correlation between the UCLA PTSD RI and ASC-Kids found to be good; both ASC-Kids and UCLA PTSD RI had a good and moderate negative correlation with SOC-13. Adolescent female rape victims were shown to have a very high level of acute stress, and the ASC-Kids was found to have sound psychometrics and can be a valuable screening instrument to support clinicians in their assessments of an indication of adolescents after potentially stressful events such as rape.

  18. Racial and gender differences on sources of acute stress and coping style among competitive athletes.

    PubMed

    Anshel, Mark H; Sutarso, Toto; Jubenville, Colby

    2009-04-01

    The authors examined racial and gender differences on sport-related sources of acute stress that competitive athletes perceived as highly intense and experienced during the competitive event. Athletes (N = 332, 176 men, 156 women; 59 African Americans: 27 men, 32 women; 232 Caucasians: 125 men, 107 women; and 41 Hispanics: 24 men, 17 women) who competed in sport on a high school or college team participated in this study. The sources of the acute stress and the coping style in sport scales, which M. H. Anshel and T. Sutarso (2007) developed, required the athletes to indicate their perceived stress intensity and their "typical" coping responses after experiencing the two stressors they perceived as most intense. A multivarite analysis of variance indicated that Caucasians experienced higher stress intensity more often than did African Americans on each of two sources of acute stress, and Caucasians tended to use an approach-behavior coping style. Women reported higher stress intensity for coach-related sources of acute stress and used approach-behavioral and avoidance-cognitive coping styles more often than did their male counterparts. Hispanic athletes did not differ from other groups on any measure. The authors conclude that race and gender influence the coping process in competitive sport.

  19. Acute myocardial infarction and stress cardiomyopathy following the Christchurch earthquakes.

    PubMed

    Chan, Christina; Elliott, John; Troughton, Richard; Frampton, Christopher; Smyth, David; Crozier, Ian; Bridgman, Paul

    2013-01-01

    Christchurch, New Zealand, was struck by 2 major earthquakes at 4:36 am on 4 September 2010, magnitude 7.1 and at 12:51 pm on 22 February 2011, magnitude 6.3. Both events caused widespread destruction. Christchurch Hospital was the region's only acute care hospital. It remained functional following both earthquakes. We were able to examine the effects of the 2 earthquakes on acute cardiac presentations. Patients admitted under Cardiology in Christchurch Hospital 3 week prior to and 5 weeks following both earthquakes were analysed, with corresponding control periods in September 2009 and February 2010. Patients were categorised based on diagnosis: ST elevation myocardial infarction, Non ST elevation myocardial infarction, stress cardiomyopathy, unstable angina, stable angina, non cardiac chest pain, arrhythmia and others. There was a significant increase in overall admissions (p<0.003), ST elevation myocardial infarction (p<0.016), and non cardiac chest pain (p<0.022) in the first 2 weeks following the early morning September earthquake. This pattern was not seen after the early afternoon February earthquake. Instead, there was a very large number of stress cardiomyopathy admissions with 21 cases (95% CI 2.6-6.4) in 4 days. There had been 6 stress cardiomyopathy cases after the first earthquake (95% CI 0.44-2.62). Statistical analysis showed this to be a significant difference between the earthquakes (p<0.05). The early morning September earthquake triggered a large increase in ST elevation myocardial infarction and a few stress cardiomyopathy cases. The early afternoon February earthquake caused significantly more stress cardiomyopathy. Two major earthquakes occurring at different times of day differed in their effect on acute cardiac events.

  20. Relationship between cognitive emotion regulation, social support, resilience and acute stress responses in Chinese soldiers: Exploring multiple mediation model.

    PubMed

    Cai, Wen-Peng; Pan, Yu; Zhang, Shui-Miao; Wei, Cun; Dong, Wei; Deng, Guang-Hui

    2017-10-01

    The current study aimed to explore the association of cognitive emotion regulation, social support, resilience and acute stress responses in Chinese soldiers and to understand the multiple mediation effects of social support and resilience on the relationship between cognitive emotion regulation and acute stress responses. A total of 1477 male soldiers completed mental scales, including the cognitive emotion regulation questionnaire-Chinese version, the perceived social support scale, the Chinese version of the Connor-Davidson resilience scale, and the military acute stress scale. As hypothesized, physiological responses, psychological responses, and acute stress were associated with negative-focused cognitive emotion regulation, and negatively associated with positive-focused cognitive emotion regulation, social supports and resilience. Besides, positive-focused cognitive emotion regulation, social support, and resilience were significantly associated with one another, and negative-focused cognitive emotion regulation was negatively associated with social support. Regression analysis and bootstrap analysis showed that social support and resilience had partly mediating effects on negative strategies and acute stress, and fully mediating effects on positive strategies and acute stress. These results thus indicate that military acute stress is significantly associated with cognitive emotion regulation, social support, and resilience, and that social support and resilience have multiple mediation effects on the relationship between cognitive emotion regulation and acute stress responses. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Body temperature responses to handling stress in wintering Black-capped Chickadees (Poecile atricapillus L.).

    PubMed

    Lewden, Agnès; Nord, Andreas; Petit, Magali; Vézina, François

    2017-10-01

    Body temperature variation in response to acute stress is typically characterized by peripheral vasoconstriction and a concomitant increase in core body temperature (stress-induced hyperthermia). It is poorly understood how this response differs between species and within individuals of the same species, and how it is affected by the environment. We therefore investigated stress-induced body temperature changes in a non-model species, the Black-capped Chickadee, in two environmental conditions: outdoors in low ambient temperature (mean: -6.6°C), and indoors, in milder ambient temperature close to thermoneutrality (mean: 18.7°C). Our results show that the change in body temperature in response to the same handling stressor differs in these conditions. In cold environments, we noted a significant decrease in core body temperature (-2.9°C), whereas the response in mild indoor conditions was weak and non-significant (-0.6°C). Heat loss in outdoor birds was exacerbated when birds were handled for longer time. This may highlight the role of behavioral thermoregulation and heat substitution from activity to body temperature maintenance in harsh condition. Importantly, our work also indicates that changes in the physical properties of the bird during handling (conductive cooling from cold hands, decreased insulation from compression of plumage and prevention of ptiloerection) may have large consequences for thermoregulation. This might explain why females, the smaller sex, lost more heat than males in the experiment. Because physiological and physical changes during handling may carry over to affect predation risk and maintenance of energy balance during short winter days, we advice caution when designing experimental protocols entailing prolonged handling of small birds in cold conditions. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. StressModEx--Physiotherapist-led Stress Inoculation Training integrated with exercise for acute whiplash injury: study protocol for a randomised controlled trial.

    PubMed

    Ritchie, Carrie; Kenardy, Justin; Smeets, Rob; Sterling, Michele

    2015-07-01

    Whiplash associated disorders are the most common non-hospitalised injuries following a road traffic crash. Up to 50% of individuals who experience a whiplash injury will not fully recover and report ongoing pain and disability. Most recovery, if it occurs, takes place in the first 2-3 months post injury, indicating that treatment provided in the early stages is critical to long-term outcome. However, early management approaches for people with acute whiplash associated disorders are modestly effective. One reason may be that the treatments have been non-specific and have not targeted the processes shown to be associated with poor recovery, such as post-traumatic stress symptoms. Targeting and modulating these early stress responses in the early management of acute whiplash associated disorders may improve health outcomes. Early aggressive psychological interventions in the form of psychological debriefing may be detrimental to recovery and are now not recommended for management of early post-traumatic stress symptoms. In contrast, Stress Inoculation Training (SIT) is a cognitive behavioural approach that teaches various general problem-solving and coping strategies to manage stress-related anxiety (ie, relaxation training, cognitive restructuring and positive self-statements) and provides important information to injured individuals about the impact of stress on their physical and psychological wellbeing. While referral to a psychologist may be necessary in some cases where acute stress disorder or other more significant psychological reactions to stress are evident, in the case of acute whiplash injuries, it is neither feasible nor necessary for a psychologist to deliver the early stress modulation intervention to all injured individuals. The feasibility of using other specially trained health professionals to deliver psychological interventions has been explored in conditions such as chronic low back pain, chronic whiplash and cancer, but few trials have studied

  3. Timing matters: the interval between acute stressors within chronic mild stress modifies behavioral and physiologic stress responses in male rats.

    PubMed

    Cavigelli, Sonia A; Bao, Alexander D; Bourne, Rebecca A; Caruso, Michael J; Caulfield, Jasmine I; Chen, Mary; Smyth, Joshua M

    2018-04-12

    Chronic mild stress can lead to negative health outcomes. Frequency, duration, and intensity of acute stressors can affect health-related processes. We tested whether the temporal pattern of daily acute stressors (clustered or dispersed across the day) affects depression-related physiology. We used a rodent model to keep stressor frequency, duration, and intensity constant, and experimentally manipulated the temporal pattern of acute stressors delivered during the active phase of the day. Adult male Sprague-Dawley rats were exposed to one of three chronic mild stress groups: Clustered: stressors that occurred within 1 hour of each other (n = 21), Dispersed: stressors that were spread out across the active phase (n = 21), and Control: no stressors presented (n = 21). Acute mild stressors included noise, strobe lights, novel cage, cage tilt, wet bedding, and water immersion. Depression-related outcomes included: sucrose preference, body weight, circulating glucocorticoid (corticosterone) concentration after a novel acute stressor and during basal morning and evening times, and endotoxin-induced circulating interleukin-6 concentrations. Compared to control rats, those in the Clustered group gained less weight, consumed less sucrose, had a blunted acute corticosterone response, and an accentuated acute interleukin-6 response. Rats in the Dispersed group had an attenuated corticosterone decline during the active period and after an acute stressor compared to the Control group. During a chronic mild stress experience, the temporal distribution of daily acute stressors affected health-related physiologic processes. Regular exposure to daily stressors in rapid succession may predict more depression-related symptoms, whereas exposure to stressors dispersed throughout the day may predict diminished glucocorticoid negative feedback.

  4. Acute stress in residents during emergency care: a study of personal and situational factors.

    PubMed

    Dias, Roger Daglius; Scalabrini Neto, Augusto

    2017-05-01

    Providing care for simulated emergency patients may induce considerable acute stress in physicians. However, the acute stress provoked in a real-life emergency room (ER) is not well known. Our aim was to assess acute stress responses in residents during real emergency care and investigate the related personal and situational factors. A cross-sectional observational study was carried out at an emergency department of a tertiary teaching hospital. All second-year internal medicine residents were invited to voluntarily participate in this study. Acute stress markers were assessed at baseline (T1), before residents started their ER shift, and immediately after an emergency situation (T2), using heart rate, systolic, and diastolic blood pressure, salivary α-amylase activity, salivary interleukin-1 β, and the State-Trait Anxiety Inventory (STAI-s and STAI-t). Twenty-four residents were assessed during 40 emergency situations. All stress markers presented a statistically significant increase between T1 and T2. IL-1 β presented the highest percent increase (141.0%, p < .001), followed by AA (99.0%, p = .002), HR (81.0%, p < .001), DBP (8.0%, p < .001), and SBP (3.0%, p < .001). In the multivariable analysis, time of residency had a negative correlation with HR during the emergency (adjusted R-square = .168; F = 8.69; p = .006), SBP response (adjusted R-square = .210; F = 6.19; p = .005) and DBP response (adjusted R-square = .293; F = 9.09; p = .001). Trait anxiety (STAI-t) was positively correlated with STAI-s (adjusted R-square = .326; F = 19.9; p < .001), and number of procedures performed during emergency care had a positive association with HR response (adjusted R-square = .241; F = 5.02; p = .005). In the present study, emergency care provoked substantial acute stress in residents. Resident experience, trait anxiety, and number of emergency procedures were independently associated with

  5. Acute stress enhances adult rat hippocampal neurogenesis and activation of newborn neurons via secreted astrocytic FGF2

    PubMed Central

    Kirby, Elizabeth D; Muroy, Sandra E; Sun, Wayne G; Covarrubias, David; Leong, Megan J; Barchas, Laurel A; Kaufer, Daniela

    2013-01-01

    Stress is a potent modulator of the mammalian brain. The highly conserved stress hormone response influences many brain regions, particularly the hippocampus, a region important for memory function. The effect of acute stress on the unique population of adult neural stem/progenitor cells (NPCs) that resides in the adult hippocampus is unclear. We found that acute stress increased hippocampal cell proliferation and astrocytic fibroblast growth factor 2 (FGF2) expression. The effect of acute stress occurred independent of basolateral amygdala neural input and was mimicked by treating isolated NPCs with conditioned media from corticosterone-treated primary astrocytes. Neutralization of FGF2 revealed that astrocyte-secreted FGF2 mediated stress-hormone-induced NPC proliferation. 2 weeks, but not 2 days, after acute stress, rats also showed enhanced fear extinction memory coincident with enhanced activation of newborn neurons. Our findings suggest a beneficial role for brief stress on the hippocampus and improve understanding of the adaptive capacity of the brain. DOI: http://dx.doi.org/10.7554/eLife.00362.001 PMID:23599891

  6. Personality and physiological reactions to acute psychological stress.

    PubMed

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

    2013-10-01

    Stable personality traits have long been presumed to have biological substrates, although the evidence relating personality to biological stress reactivity is inconclusive. The present study examined, in a large middle aged cohort (N=352), the relationship between key personality traits and both cortisol and cardiovascular reactions to acute psychological stress. Salivary cortisol and cardiovascular activity were measured at rest and in response to a psychological stress protocol comprising 5min each of a Stroop task, mirror tracing, and a speech task. Participants subsequently completed the Big Five Inventory to assess neuroticism, agreeableness, openness to experience, extraversion, and conscientiousness. Those with higher neuroticism scores exhibited smaller cortisol and cardiovascular stress reactions, whereas participants who were less agreeable and less open had smaller cortisol and cardiac reactions to stress. These associations remained statistically significant following adjustment for a range of potential confounding variables. Thus, a negative personality disposition would appear to be linked to diminished stress reactivity. These findings further support a growing body of evidence which suggests that blunted stress reactivity may be maladaptive. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Do acute phase markers explain body temperature and brain temperature after ischemic stroke?

    PubMed Central

    Whiteley, William N.; Thomas, Ralph; Lowe, Gordon; Rumley, Ann; Karaszewski, Bartosz; Armitage, Paul; Marshall, Ian; Lymer, Katherine; Dennis, Martin

    2012-01-01

    Objective: Both brain and body temperature rise after stroke but the cause of each is uncertain. We investigated the relationship between circulating markers of inflammation with brain and body temperature after stroke. Methods: We recruited patients with acute ischemic stroke and measured brain temperature at hospital admission and 5 days after stroke with multivoxel magnetic resonance spectroscopic imaging in normal brain and the acute ischemic lesion (defined by diffusion-weighted imaging [DWI]). We measured body temperature with digital aural thermometers 4-hourly and drew blood daily to measure interleukin-6, C-reactive protein, and fibrinogen, for 5 days after stroke. Results: In 44 stroke patients, the mean temperature in DWI-ischemic brain soon after admission was 38.4°C (95% confidence interval [CI] 38.2–38.6), in DWI-normal brain was 37.7°C (95% CI 37.6–37.7), and mean body temperature was 36.6°C (95% CI 36.3–37.0). Higher mean levels of interleukin-6, C-reactive protein, and fibrinogen were associated with higher temperature in DWI-normal brain at admission and 5 days, and higher overall mean body temperature, but only with higher temperature in DWI-ischemic brain on admission. Conclusions: Systemic inflammation after stroke is associated with elevated temperature in normal brain and the body but not with later ischemic brain temperature. Elevated brain temperature is a potential mechanism for the poorer outcome observed in stroke patients with higher levels of circulating inflammatory markers. PMID:22744672

  8. The stress relaxation of cement clinkers under high temperature

    NASA Astrophysics Data System (ADS)

    Wang, Xiufang; Bao, Yiwang; Liu, Xiaogen; Qiu, Yan

    2015-12-01

    The energy consumption of crushing is directly affected by the mechanical properties of cement materials. This research provides a theoretical proof for the mechanism of the stress relaxation of cement clinkers under high temperature. Compression stress relaxation under various high temperatures is discussed using a specially developed load cell, which can measure stress and displacement under high temperatures inside an autoclave. The cell shows that stress relaxation dramatically increases and that the remaining stress rapidly decreases with an increase in temperature. Mechanical experiments are conducted under various temperatures during the cooling process to study the changes in the grinding resistance of the cement clinker with temperature. The effects of high temperature on the load-displacement curve, compressive strength, and elastic modulus of cement clinkers are systematically studied. Results show that the hardening phenomenon of the clinker becomes apparent with a decrease in temperature and that post-peak behaviors manifest characteristics of the transformation from plasticity to brittleness. The elastic modulus and compressive strength of cement clinkers increase with a decrease in temperature. The elastic modulus increases greatly when the temperature is lower than 1000 °C. The compressive strength of clinkers increases by 73.4% when the temperature drops from 1100 to 800 °C.

  9. Repeated Exposure to Conditioned Fear Stress Increases Anxiety and Delays Sleep Recovery Following Exposure to an Acute Traumatic Stressor

    PubMed Central

    Greenwood, Benjamin N.; Thompson, Robert S.; Opp, Mark R.; Fleshner, Monika

    2014-01-01

    Repeated stressor exposure can sensitize physiological responses to novel stressors and facilitate the development of stress-related psychiatric disorders including anxiety. Disruptions in diurnal rhythms of sleep–wake behavior accompany stress-related psychiatric disorders and could contribute to their development. Complex stressors that include fear-eliciting stimuli can be a component of repeated stress experienced by human beings, but whether exposure to repeated fear can prime the development of anxiety and sleep disturbances is unknown. In the current study, adult male F344 rats were exposed to either control conditions or repeated contextual fear conditioning for 22 days followed by exposure to no, mild (10), or severe (100) acute uncontrollable tail shock stress. Exposure to acute stress produced anxiety-like behavior as measured by a reduction in juvenile social exploration and exaggerated shock-elicited freezing in a novel context. Prior exposure to repeated fear enhanced anxiety-like behavior as measured by shock-elicited freezing, but did not alter social exploratory behavior. The potentiation of anxiety produced by prior repeated fear was temporary; exaggerated fear was present 1 day but not 4 days following acute stress. Interestingly, exposure to acute stress reduced rapid eye movement (REM) and non-REM (NREM) sleep during the hours immediately following acute stress. This initial reduction in sleep was followed by robust REM rebound and diurnal rhythm flattening of sleep/wake behavior. Prior repeated fear extended the acute stress-induced REM and NREM sleep loss, impaired REM rebound, and prolonged the flattening of the diurnal rhythm of NREM sleep following acute stressor exposure. These data suggest that impaired recovery of sleep/wake behavior following acute stress could contribute to the mechanisms by which a history of prior repeated stress increases vulnerability to subsequent novel stressors and stress-related disorders. PMID

  10. Stressful events and coping related to acute and sub-acute whiplash-associated disorders.

    PubMed

    Pettersson, Susanne; Bring, Annika; Åsenlöf, Pernilla

    2017-03-01

    Purpose To describe daily stressors affecting and coping strategies employed by individuals with whiplash-associated disorders (WAD) immediately to one month (acute) and three to four months (sub-acute) after injury events using a daily coping assessment. Levels of pain, anxiety, depressed mood and activity are also compared between phases. Method A descriptive prospective design with a content analysis approach was used. Participants completed daily coping assessments for one week during both acute and sub-acute phases. Main measure was whiplash-associated disorders-daily coping assessment (WAD-DCA). Results Nine participants used words describing recovery in the sub-acute phase; 31 described stressful events during both phases. Most frequently reported stressors were related to "symptoms", "emotions" and "occupations/studies". These were equally reported during both phases. Cognitive coping strategies were employed more often during the sub-acute phase (p = 0.008). The only behavioral strategy that increased in prevalence over time was the "relaxed" strategy (p = 0.001). Anxiety levels declined over time (p = 0.022). Conclusion The reported stressors were largely uniform across both acute and sub-acute phases; however, the use of cognitive coping strategies increased over time. The WAD-DCA captures individual stressors and coping strategies employed during a vulnerable phase of rehabilitation and can thus provide information that is useful to clinical practice. Implications for rehabilitation The WAD-DCA provides valuable information for clinical practice when employed during early phases of whiplash-associated disorder development. Reported stressors during the acute and sub-acute phases are essentially the same, whereas cognitive coping strategies grow in prevalence over time. Tailored treatments in early phases of whip-lash associated disorders may benefit from strategies aimed at matching patient-specific stressors with contextually adapted coping

  11. Intrinsic and extrinsic apoptotic pathways are involved in rat testis by cold water immersion-induced acute and chronic stress.

    PubMed

    Juárez-Rojas, Adriana Lizbeth; García-Lorenzana, Mario; Aragón-Martínez, Andrés; Gómez-Quiroz, Luis Enrique; Retana-Márquez, María del Socorro

    2015-01-01

    Testicular apoptosis is activated by stress, but it is not clear which signaling pathway is activated in response to stress. The aim of this study was to investigate whether intrinsic, extrinsic, or both apoptotic signaling pathways are activated by acute and chronic stress. Adult male rats were subjected to cold water immersion-induced stress for 1, 20, 40, and 50 consecutive days. The seminiferous tubules:apoptotic cell ratio was assayed on acute (1 day) and chronic (20, 40, 50 days) stress. Apoptotic markers, including cleaved-caspase 3 and 8, the pro-apoptotic Bax and anti-apoptotic Bcl-2 proteins were also determined after acute and chronic stress induction. Additionally, epididymal sperm quality was evaluated, as well as corticosterone and testosterone levels. An increase in tubule apoptotic cell count percentage after an hour of acute stress and during chronic stress induction was observed. The apoptotic cells rate per tubule increment was only detected one hour after acute stress, but not with chronic stress. Accordingly, there was an increase in Bax, cleaved caspase-8 and caspase-3 pro-apoptotic proteins with a decrease of anti-apoptotic Bcl-2 in both acutely and chronically stressed male testes. In addition, sperm count, viability, as well as total and progressive motility were low in chronically stressed males. Finally, the levels of corticosterone increased whereas testosterone levels decreased in chronically stressed males. Activation of the extrinsic apoptotic pathway was shown by cleaved caspase-8 increase whereas the intrinsic apoptotic pathway activation was determined by the increase of Bax, along with Bcl-2 decrease, making evident a cross-talk between these two pathways with the activation of caspase-3. These results suggest that both acute and chronic stress can potentially activate the intrinsic/extrinsic apoptosis pathways in testes. Chronic stress also reduces the quality of epididymal spermatozoa, possibly due to a decrease in testosterone.

  12. Acute stress impairs cognitive flexibility in men, not women.

    PubMed

    Shields, Grant S; Trainor, Brian C; Lam, Jovian C W; Yonelinas, Andrew P

    2016-09-01

    Psychosocial stress influences cognitive abilities, such as long-term memory retrieval. However, less is known about the effects of stress on cognitive flexibility, which is mediated by different neurobiological circuits and could thus be regulated by different neuroendocrine pathways. In this study, we randomly assigned healthy adults to an acute stress induction or control condition and subsequently assessed participants' cognitive flexibility using an open-source version of the Wisconsin Card Sort task. Drawing on work in rodents, we hypothesized that stress would have stronger impairing effects on cognitive flexibility in men than women. As predicted, we found that stress impaired cognitive flexibility in men but did not significantly affect women. Our results thus indicate that stress exerts sex-specific effects on cognitive flexibility in humans and add to the growing body of research highlighting the need to consider sex differences in effects of stress.

  13. Acute Myocardial Infarction and Stress Cardiomyopathy following the Christchurch Earthquakes

    PubMed Central

    Chan, Christina; Elliott, John; Troughton, Richard; Frampton, Christopher; Smyth, David; Crozier, Ian; Bridgman, Paul

    2013-01-01

    Background Christchurch, New Zealand, was struck by 2 major earthquakes at 4:36am on 4 September 2010, magnitude 7.1 and at 12:51pm on 22 February 2011, magnitude 6.3. Both events caused widespread destruction. Christchurch Hospital was the region's only acute care hospital. It remained functional following both earthquakes. We were able to examine the effects of the 2 earthquakes on acute cardiac presentations. Methods Patients admitted under Cardiology in Christchurch Hospital 3 week prior to and 5 weeks following both earthquakes were analysed, with corresponding control periods in September 2009 and February 2010. Patients were categorised based on diagnosis: ST elevation myocardial infarction, Non ST elevation myocardial infarction, stress cardiomyopathy, unstable angina, stable angina, non cardiac chest pain, arrhythmia and others. Results There was a significant increase in overall admissions (p<0.003), ST elevation myocardial infarction (p<0.016), and non cardiac chest pain (p<0.022) in the first 2 weeks following the early morning September earthquake. This pattern was not seen after the early afternoon February earthquake. Instead, there was a very large number of stress cardiomyopathy admissions with 21 cases (95% CI 2.6–6.4) in 4 days. There had been 6 stress cardiomyopathy cases after the first earthquake (95% CI 0.44–2.62). Statistical analysis showed this to be a significant difference between the earthquakes (p<0.05). Conclusion The early morning September earthquake triggered a large increase in ST elevation myocardial infarction and a few stress cardiomyopathy cases. The early afternoon February earthquake caused significantly more stress cardiomyopathy. Two major earthquakes occurring at different times of day differed in their effect on acute cardiac events. PMID:23844213

  14. Silymarin Prevents Restraint Stress-Induced Acute Liver Injury by Ameliorating Oxidative Stress and Reducing Inflammatory Response.

    PubMed

    Kim, Sou Hyun; Oh, Dal-Seok; Oh, Ji Youn; Son, Tae Gen; Yuk, Dong Yeon; Jung, Young-Suk

    2016-04-01

    Silymarin is a flavonoid extracted from the milk thistle Silybum marianum. It has been reported to prevent liver injuries induced by various chemicals or toxins. Our recent study suggested that silymarin induces hepatic synthesis of glutathione by increasing cysteine availability, which may consequently contribute to increased antioxidant capacity of the liver. In the present study, we investigated the effects of silymarin on acute liver injury induced by restraint stress. Silymarin (100 mg/kg) was orally administered to BALB/c mice every 12 h (3 times in total). After the last dose, mice were subjected to restraint stress for 6 h, and serum levels of aspartate and alanine aminotransferases, and hepatic levels of lipid peroxidation were determined. Hepatic levels of sulfur-containing metabolites such as methionine, S-adenosylmethionine, cysteine, and glutathione were also measured. The level of pro-inflammatory mediators in both liver and serum was determined. To study the mechanism of the effects of silymarin, we assessed Jun N-terminal kinase (JNK) activation and apoptotic signaling. Restraint stress induced severe oxidative stress and increased mRNA levels of pro-inflammatory mediators; both effects of restraint stress were significantly inhibited by silymarin. Moreover, administration of silymarin significantly prevented acute liver injury induced by restraint stress by blocking JNK activation and subsequently apoptotic signaling. In conclusion, these results suggest that the inhibition of restraint stress-induced liver injury by silymarin is due at least in part to its anti-oxidant activity and its ability to suppress the inflammatory response.

  15. Acute Stress Disorder: Conceptual Issues and Treatment Outcomes

    ERIC Educational Resources Information Center

    Koucky, Ellen M.; Galovski, Tara E.; Nixon, Reginald D. V.

    2012-01-01

    Acute stress disorder (ASD) was included as a diagnosis to the 4th edition of the "Diagnostic and Statistical Manual" (American Psychiatric Association, 1994) as a way of describing pathological reactions in the first month following a trauma. Since that time, ASD has been the focus of some controversy, particularly regarding the theoretical basis…

  16. Exposure of Lactating Dairy Cows to Acute Pre-Ovulatory Heat Stress Affects Granulosa Cell-Specific Gene Expression Profiles in Dominant Follicles

    PubMed Central

    Vanselow, Jens; Vernunft, Andreas; Koczan, Dirk; Spitschak, Marion; Kuhla, Björn

    2016-01-01

    High environmental temperatures induce detrimental effects on various reproductive processes in cattle. According to the predicted global warming the number of days with unfavorable ambient temperatures will further increase. The objective of this study was to investigate effects of acute heat stress during the late pre-ovulatory phase on morphological, physiological and molecular parameters of dominant follicles in cycling cows during lactation. Eight German Holstein cows in established lactation were exposed to heat stress (28°C) or thermoneutral conditions (15°C) with pair-feeding for four days. After hormonal heat induction growth of the respective dominant follicles was monitored by ultrasonography for two days, then an ovulatory GnRH dose was given and follicular steroid hormones and granulosa cell-specific gene expression profiles were determined 23 hrs thereafter. The data showed that the pre-ovulatory growth of dominant follicles and the estradiol, but not the progesterone concentrations tended to be slightly affected. mRNA microarray and hierarchical cluster analysis revealed distinct expression profiles in granulosa cells derived from heat stressed compared to pair-fed animals. Among the 255 affected genes heatstress-, stress- or apoptosis associated genes were not present. But instead, we found up-regulation of genes essentially involved in G-protein coupled signaling pathways, extracellular matrix composition, and several members of the solute carrier family as well as up-regulation of FST encoding follistatin. In summary, the data of the present study show that acute pre-ovulatory heat stress can specifically alter gene expression profiles in granulosa cells, however without inducing stress related genes and pathways and suggestively can impair follicular growth due to affecting the activin-inhibin-follistatin system. PMID:27532452

  17. Exposure of Lactating Dairy Cows to Acute Pre-Ovulatory Heat Stress Affects Granulosa Cell-Specific Gene Expression Profiles in Dominant Follicles.

    PubMed

    Vanselow, Jens; Vernunft, Andreas; Koczan, Dirk; Spitschak, Marion; Kuhla, Björn

    2016-01-01

    High environmental temperatures induce detrimental effects on various reproductive processes in cattle. According to the predicted global warming the number of days with unfavorable ambient temperatures will further increase. The objective of this study was to investigate effects of acute heat stress during the late pre-ovulatory phase on morphological, physiological and molecular parameters of dominant follicles in cycling cows during lactation. Eight German Holstein cows in established lactation were exposed to heat stress (28°C) or thermoneutral conditions (15°C) with pair-feeding for four days. After hormonal heat induction growth of the respective dominant follicles was monitored by ultrasonography for two days, then an ovulatory GnRH dose was given and follicular steroid hormones and granulosa cell-specific gene expression profiles were determined 23 hrs thereafter. The data showed that the pre-ovulatory growth of dominant follicles and the estradiol, but not the progesterone concentrations tended to be slightly affected. mRNA microarray and hierarchical cluster analysis revealed distinct expression profiles in granulosa cells derived from heat stressed compared to pair-fed animals. Among the 255 affected genes heatstress-, stress- or apoptosis associated genes were not present. But instead, we found up-regulation of genes essentially involved in G-protein coupled signaling pathways, extracellular matrix composition, and several members of the solute carrier family as well as up-regulation of FST encoding follistatin. In summary, the data of the present study show that acute pre-ovulatory heat stress can specifically alter gene expression profiles in granulosa cells, however without inducing stress related genes and pathways and suggestively can impair follicular growth due to affecting the activin-inhibin-follistatin system.

  18. The acute autonomic stress response and amniotic fluid glucocorticoids in second-trimester pregnant women.

    PubMed

    La Marca-Ghaemmaghami, Pearl; Dainese, Sara M; La Marca, Roberto; Zimmermann, Roland; Ehlert, Ulrike

    2015-01-01

    The maternal autonomic nervous system (ANS) has received little attention in the investigation of biological mechanisms linking prenatal stress to fetal cortisol (F) excess. In vitro, norepinephrine and epinephrine inhibit placental 11β-hydroxysteroid dehydrogenase type 2 (11β-HSD2), which protects the fetus from F overexposure by inactivating it to cortisone (E). Here, we investigated the acute ANS stress response to an amniocentesis and its association with amniotic fluid F, E, and E/(E + F) as a marker of fetoplacental 11β-HSD2 activity. An aliquot of amniotic fluid was obtained from 34 healthy, second-trimester pregnant women undergoing amniocentesis. Repeated assessment of mood states served to examine the psychological stress response to amniocentesis. Saliva samples were collected to measure stress-induced changes in salivary α-amylase concentrations in response to amniocentesis. Cardiac parameters were measured continuously. Undergoing amniocentesis induced significant psychological and autonomic alterations. Low-frequency (LF)/high-frequency (HF) baseline, suggested to reflect sympathovagal balance, was negatively correlated with amniotic E/(E + F) (r=-0.53, p = .002) and positively with F (r = 0.62, p < .001). In contrast, a stronger acute LF/HF response was positively associated with E/(E + F) (r = 0.44, p = .012) and negatively with F (r=-0.40, p = .025). These findings suggest that the maternal ANS is involved in the regulation of the fetoplacental barrier to stress. Allostatic processes may have been initiated to counterbalance acute stress effects. In contrast, higher LF/HF baseline values, possibly indicative of chronic stress exposure, may have inhibited 11β-HSD2 activity in the fetoplacental unit. These results parallel animal findings of up-regulated placental 11β-HSD2 in response to acute stress but impairment under chronic stress.

  19. The effects of acute foot shock stress on empathy levels in rats.

    PubMed

    Karakilic, Aslı; Kizildag, Servet; Kandis, Sevim; Guvendi, Guven; Koc, Basar; Camsari, Gamze B; Camsari, Ulas M; Ates, Mehmet; Arda, Sevil Gonenc; Uysal, Nazan

    2018-09-03

    Empathy defined as the ability to understand and the share the feelings, thoughts, and attitudes of another, is an important skill in survival and reproduction. Among many factors that affect empathy include psychological stress, anxiety states. The aim of this study was to investigate the impact of acute psychological stress on empathic behavior and its association with oxytocin and vasopressin levels in amygdala and prefrontal cortex. Rats were subjected to 0.2 mA (low) and 1.6 mA (high) intensity of foot shock stress for duration of 20 min. Empathic behavior was found to be improved as a response to low intensity stress, but not to high intensity stress. As a response to lower intensity stress, vasopressin was increased in prefrontal cortex and amygdala; oxytocin was increased in only prefrontal cortex, and corticosterone levels increased in general. Anxiety indicators did not change in low intensity stress group yet; high intensity stress group demonstrated a lesser degree of anxiety response. High intensity stress group stayed unexpectedly more active in middle area of elevated plus maze test equipment, which may support impaired executive decision making abilities in the setting of high anxiety states. Further research is needed to investigate gender effects, the role of dopaminergic system and other stress related pathways in acute stress. Copyright © 2018 Elsevier B.V. All rights reserved.

  20. Behavioral Predictors of Acute Stress Symptoms During Intense Military Training

    DTIC Science & Technology

    2009-06-01

    the Ways of Coping Scale ( Folkman & Lazarus , 1988). During survival training, the Clinician- Administered Dissociative States Scale (Bremner et al...Published on behalf of the International Society for Traumatic Stress Studies. Acute Stress Symptoms 217 Folkman , S., & Lazarus , R. (1988). Manual...and performance in sport (pp. 17–42). Chichester, UK: Wiley. Lazarus , R. S. (2000). Cognitive-motivational-relational theory of emotion. In Y . Hanin

  1. Effects of acute handling stress on short-term central expression of orexigenic/anorexigenic genes in zebrafish.

    PubMed

    Cortés, Raul; Teles, Mariana; Oliveira, Miguel; Fierro-Castro, Camino; Tort, Lluis; Cerdá-Reverter, José Miguel

    2018-02-01

    Physiological mechanisms driving stress response in vertebrates are evolutionarily conserved. These mechanisms involve the activation of both the hypothalamic-sympathetic-chromaffin cell (HSC) and the hypothalamic-pituitary-adrenal (HPA) axes. In fish, the reduction of food intake levels is a common feature of the behavioral response to stress but the central mechanisms coordinating the energetic response are not well understood yet. In this work, we explore the effects of acute stress on key central systems regulating food intake in fish as well as on total body cortisol and glucose levels. We show that acute stress induced a rapid increase in total body cortisol with no changes in body glucose, at the same time promoting a prompt central response by activating neuronal pathways. All three orexigenic peptides examined, i.e., neuropeptide y (npy), agouti-related protein (agrp), and ghrelin, increased their central expression level suggesting that these neuronal systems are not involved in the short-term feeding inhibitory effects of acute stress. By contrast, the anorexigenic precursors tested, i.e., cart peptides and pomc, exhibited increased expression after acute stress, suggesting their involvement in the anorexigenic effects.

  2. Dynamic changes in saliva after acute mental stress

    PubMed Central

    Naumova, Ella A.; Sandulescu, Tudor; Bochnig, Clemens; Khatib, Philipp Al; Lee, Wing-Kee; Zimmer, Stefan; Arnold, Wolfgang H.

    2014-01-01

    Stress-related variations of fluoride concentration in supernatant saliva and salivary sediment, salivary cortisol, total protein and pH after acute mental stress were assessed. The hypothesis was that stress reactions have no influence on these parameters. Thirty-four male students were distributed into two groups: first received the stress exposure followed by the same protocol two weeks later but without stress exposure, second underwent the protocol without stress exposure followed by the stress exposure two weeks later. The stressor was a public speech followed by tooth brushing. Saliva was collected before, immediately after stress induction and immediately, at 10, 30 and 120 min. after tooth brushing. Cortisol concentrations, total protein, intraoral pH, and fluoride content in saliva were measured. The data were analyzed statistically. Salivary sediment was ca 4.33% by weight of whole unstimulated saliva. Fluoride bioavailability was higher in salivary sediment than in supernatant saliva. The weight and fluoride concentration was not altered during 2 hours after stress exposure. After a public speech, the salivary cortisol concentration significantly increased after 20 minutes compared to the baseline. The salivary protein concentration and pH also increased. Public speaking influences protein concentration and salivary pH but does not alter the fluoride concentration of saliva. PMID:24811301

  3. Development and psychometric evaluation of child acute stress measures in Spanish and English.

    PubMed

    Kassam-Adams, Nancy; Gold, Jeffrey I; Montaño, Zorash; Kohser, Kristen L; Cuadra, Anai; Muñoz, Cynthia; Armstrong, F Daniel

    2013-02-01

    Clinicians and researchers need tools for accurate early assessment of children's acute stress reactions and acute stress disorder (ASD). There is a particular need for independently validated Spanish-language measures. The current study reports on 2 measures of child acute stress (a self-report checklist and a semistructured interview), describing the development of the Spanish version of each measure and psychometric evaluation of both the Spanish and English versions. Children between the ages of 8 to 17 years who had experienced a recent traumatic event completed study measures in Spanish (n = 225) or in English (n = 254). Results provide support for reliability (internal consistency of the measures in both languages ranged from .83 to .89; cross-language reliability of the checklist was .93) and for convergent validity (with later PTSD symptoms, and with concurrent anxiety symptoms). Comparing checklist and interview results revealed a strong association between severity scores within the Spanish and English samples. Differences between the checklist and interview in evaluating the presence of ASD appear to be linked to different content coverage for dissociation symptoms. Future studies should further assess the impact of differing assessment modes, content coverage, and the use of these measures in children with diverse types of acute trauma exposure in English- and Spanish-speaking children. Copyright © 2013 International Society for Traumatic Stress Studies.

  4. Cumulative exposure to prior collective trauma and acute stress responses to the Boston marathon bombings.

    PubMed

    Garfin, Dana Rose; Holman, E Alison; Silver, Roxane Cohen

    2015-06-01

    The role of repeated exposure to collective trauma in explaining response to subsequent community-wide trauma is poorly understood. We examined the relationship between acute stress response to the 2013 Boston Marathon bombings and prior direct and indirect media-based exposure to three collective traumatic events: the September 11, 2001 (9/11) terrorist attacks, Superstorm Sandy, and the Sandy Hook Elementary School shooting. Representative samples of residents of metropolitan Boston (n = 846) and New York City (n = 941) completed Internet-based surveys shortly after the Boston Marathon bombings. Cumulative direct exposure and indirect exposure to prior community trauma and acute stress symptoms were assessed. Acute stress levels did not differ between Boston and New York metropolitan residents. Cumulative direct and indirect, live-media-based exposure to 9/11, Superstorm Sandy, and the Sandy Hook shooting were positively associated with acute stress responses in the covariate-adjusted model. People who experience multiple community-based traumas may be sensitized to the negative impact of subsequent events, especially in communities previously exposed to similar disasters. © The Author(s) 2015.

  5. The impact of acute stress on hormones and cytokines, and how their recovery is affected by music-evoked positive mood

    PubMed Central

    Koelsch, Stefan; Boehlig, Albrecht; Hohenadel, Maximilian; Nitsche, Ines; Bauer, Katrin; Sack, Ulrich

    2016-01-01

    Stress and recovery from stress significantly affect interactions between the central nervous system, endocrine pathways, and the immune system. However, the influence of acute stress on circulating immune-endocrine mediators in humans is not well known. Using a double-blind, randomized study design, we administered a CO2 stress test to n = 143 participants to identify the effects of acute stress, and recovery from stress, on serum levels of several mediators with immune function (IL-6, TNF-α, leptin, and somatostatin), as well as on noradrenaline, and two hypothalamic–pituitary–adrenal axis hormones (ACTH and cortisol). Moreover, during a 1 h-recovery period, we repeatedly measured these serum parameters, and administered an auditory mood-induction protocol with positive music and a neutral control stimulus. The acute stress elicited increases in noradrenaline, ACTH, cortisol, IL-6, and leptin levels. Noradrenaline and ACTH exhibited the fastest and strongest stress responses, followed by cortisol, IL-6 and leptin. The music intervention was associated with more positive mood, and stronger cortisol responses to the acute stressor in the music group. Our data show that acute (CO2) stress affects endocrine, immune and metabolic functions in humans, and they show that mood plays a causal role in the modulation of responses to acute stress. PMID:27020850

  6. Protective effect of exercise and sildenafil on acute stress and cognitive function.

    PubMed

    Ozbeyli, Dilek; Gokalp, Ayse Gizem; Koral, Tolga; Ocal, Onur Yuksel; Dogan, Berkay; Akakin, Dilek; Yuksel, Meral; Kasimay, Ozgur

    2015-11-01

    There are contradictory results about the effects of exercise and sildenafil on cognitive functions. To investigate the effects of sildenafil pretreatment and chronic exercise on anxiety and cognitive functions. Wistar rats (n=42) were divided as sedentary and exercise groups. A moderate-intensity swimming exercise was performed for 6 weeks, 5 days/week, 1h/day. Some of the rats were administered orogastrically with sildenafil (25mg/kg/day) either acutely or chronically. Exposure to cat odor was used for induction of stress. The level of anxiety was evaluated by elevated plus maze test, while object recognition test was used to determine cognitive functions. Brain tissues were removed for the measurement of myeloperoxidase (MPO), malondialdehyde (MDA), nitric oxide levels, lucigenin-enhanced chemiluminescence, and for histological analysis. Increased MPO and MDA levels in sedentary-stressed rats were decreased with sildenafil applications. Chronic exercise inhibited the increase in MPO levels. Increased nitric oxide and lucigenin chemiluminescence levels in sedentary-stressed rats, were diminished with chronic sildenafil pretreatment. The time spent in the open arms of the plus maze was declined in sedentary-stressed rats, while chronic sildenafil pretreatment increased the time back to that in non-stressed rats. Acute sildenafil application to exercised rats prolonged the time spent in open arms as compared to non-treated exercise group. The time spent with the novel object, which was decreased in sedentary-stressed rats, was increased with sildenafil pretreatment. Our results suggest that sildenafil pretreatment or exercise exerts a protective effect against acute stress and improves cognitive functions by decreasing oxidative damage. Copyright © 2015 Elsevier Inc. All rights reserved.

  7. Chronic mitochondrial uncoupling treatment prevents acute cold-induced oxidative stress in birds.

    PubMed

    Stier, Antoine; Massemin, Sylvie; Criscuolo, François

    2014-12-01

    Endotherms have evolved two major types of thermogenesis that allow them to actively produce heat in response to cold exposure, either through muscular activity (i.e. shivering thermogenesis) or through futile electro-chemical cycles (i.e. non-shivering thermogenesis). Amongst the latter, mitochondrial uncoupling is of key importance because it is suggested to drive heat production at a low cost in terms of oxidative stress. While this has been experimentally shown in mammals, the oxidative stress consequences of cold exposure and mitochondrial uncoupling are clearly less understood in the other class of endotherms, the birds. We compared metabolic and oxidative stress responses of zebra finches chronically treated with or without a chemical mitochondrial uncoupler (2,4-dinitrophenol: DNP), undergoing an acute (24 h) and a chronic (4 weeks) cold exposure (12 °C). We predicted that control birds should present at least a transient elevation of oxidative stress levels in response to cold exposure. This oxidative stress cost should be more pronounced in control birds than in DNP-treated birds, due to their lower basal uncoupling state. Despite similar increase in metabolism, control birds presented elevated levels of DNA oxidative damage in response to acute (but not chronic) cold exposure, while DNP-treated birds did not. Plasma antioxidant capacity decreased overall in response to chronic cold exposure. These results show that acute cold exposure increases oxidative stress in birds. However, uncoupling mitochondrial functioning appears as a putative compensatory mechanism preventing cold-induced oxidative stress. This result confirms previous observations in mice and underlines non-shivering thermogenesis as a putative key mechanism for endotherms in mounting a response to cold at a low oxidative cost.

  8. Chronic stress decreases availability of heat shock proteins to glucocorticoid receptor in response to novel acute stress in Wistar rat hypothalamus.

    PubMed

    Simic, Iva; Mitic, Milos; Djordjevic, Jelena; Radojcic, Marija; Adzic, Miroslav

    2012-05-01

    Chronic psychosocial isolation (CPSI) is known to cause several maladaptive changes in the limbic brain structures, which regulate the hypothalamic-pituitary-adrenal (HPA) axis activity. In this study, we focused our investigation on CPSI effects in the hypothalamus (HT) since it is a major driver of HPA axis activity. We also investigated whether the exposure to CPSI could alter the response to subsequent acute stress (30-min immobilization). In the HT, we followed cytosolic and nuclear levels of the glucocorticoid receptor (GR), as a mediator of HPA axis feedback inhibition, and its chaperones, the heat shock proteins (HSPs), hsp70 and hsp90. The CPSI did not cause any changes in either GR or HSPs levels. However, we observed increase of the GR and hsp70 in both HT cellular compartments as a response of naïve rats to acute stress, whereas the response of CPSI rats to acute stress was associated with elevation of the GR in the cytosol and decrease of HSPs in the nucleus. Thus, our data indicated reduced availability of HSPs to GR in both cytosol and nucleus of the HT under acute stress of CPSI animals, and therefore, pointed out to potentially negative effects of CPSI on GR function in the HT.

  9. Visualizing Stress and Temperature Distribution During Elevated Temperature Deformation of IN-617 Using Nanomechanical Raman Spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhang, Yang; Wang, Hao; Tomar, Vikas

    2018-04-01

    This work presents direct measurements of stress and temperature distribution during the mesoscale microstructural deformation of Inconel-617 (IN-617) during 3-point bending tests as a function of temperature. A novel nanomechanical Raman spectroscopy (NMRS)-based measurement platform was designed for simultaneous in situ temperature and stress mapping as a function of microstructure during deformation. The temperature distribution was found to be directly correlated to stress distribution for the analyzed microstructures. Stress concentration locations are shown to be directly related to higher heat conduction and result in microstructural hot spots with significant local temperature variation.

  10. Factor Structure of the Acute Stress Disorder Scale in a Sample of Hurricane Katrina Evacuees

    ERIC Educational Resources Information Center

    Edmondson, Donald; Mills, Mary Alice; Park, Crystal L.

    2010-01-01

    Acute stress disorder (ASD) is a poorly understood and controversial diagnosis (A. G. Harvey & R. A. Bryant, 2002). The present study used confirmatory factor analysis (CFA) to test the factor structure of the most widely used self-report measure of ASD, the Acute Stress Disorder Scale (R. A. Bryant, M. L. Moulds, & R. M. Guthrie, 2000),…

  11. Chronic but not acute foot-shock stress leads to temporary suppression of cell proliferation in rat hippocampus.

    PubMed

    Dagyte, G; Van der Zee, E A; Postema, F; Luiten, P G M; Den Boer, J A; Trentani, A; Meerlo, P

    2009-09-15

    Stressful experiences, especially when prolonged and severe are associated with psychopathology and impaired neuronal plasticity. Among other effects on the brain, stress has been shown to negatively regulate hippocampal neurogenesis, and this effect is considered to be exerted via glucocorticoids. Here, we sought to determine the temporal dynamics of changes in hippocampal neurogenesis after acute and chronic exposure to foot-shock stress. Rats subjected to a foot-shock procedure showed strong activation of the hypothalamic-pituitary-adrenal (HPA) axis, even after exposure to daily stress for 3 weeks. Despite a robust release of corticosterone, acute foot-shock stress did not affect the rate of hippocampal cell proliferation. In contrast, exposure to foot-shock stress daily for 3 weeks led to reduced cell proliferation 2 hours after the stress procedure. Interestingly, this stress-induced effect did not persist and was no longer detected 24 hours later. Also, while chronic foot-shock stress had no impact on survival of hippocampal cells that were born before the stress procedure, it led to a decreased number of doublecortin-positive granule neurons that were born during the chronic stress period. Thus, whereas a strong activation of the HPA axis during acute foot-shock stress is not sufficient to reduce hippocampal cell proliferation, repeated exposure to stressful stimuli for prolonged period of time ultimately results in dysregulated neurogenesis. In sum, this study supports the notion that chronic stress may lead to cumulative changes in the brain that are not seen after acute stress. Such changes may indicate compromised brain plasticity and increased vulnerability to neuropathology.

  12. Aerobic Fitness Level Affects Cardiovascular and Salivary Alpha Amylase Responses to Acute Psychosocial Stress.

    PubMed

    Wyss, Thomas; Boesch, Maria; Roos, Lilian; Tschopp, Céline; Frei, Klaus M; Annen, Hubert; La Marca, Roberto

    2016-12-01

    Good physical fitness seems to help the individual to buffer the potential harmful impact of psychosocial stress on somatic and mental health. The aim of the present study is to investigate the role of physical fitness levels on the autonomic nervous system (ANS; i.e. heart rate and salivary alpha amylase) responses to acute psychosocial stress, while controlling for established factors influencing individual stress reactions. The Trier Social Stress Test for Groups (TSST-G) was executed with 302 male recruits during their first week of Swiss Army basic training. Heart rate was measured continuously, and salivary alpha amylase was measured twice, before and after the stress intervention. In the same week, all volunteers participated in a physical fitness test and they responded to questionnaires on lifestyle factors and personal traits. A multiple linear regression analysis was conducted to determine ANS responses to acute psychosocial stress from physical fitness test performances, controlling for personal traits, behavioural factors, and socioeconomic data. Multiple linear regression revealed three variables predicting 15 % of the variance in heart rate response (area under the individual heart rate response curve during TSST-G) and four variables predicting 12 % of the variance in salivary alpha amylase response (salivary alpha amylase level immediately after the TSST-G) to acute psychosocial stress. A strong performance at the progressive endurance run (high maximal oxygen consumption) was a significant predictor of ANS response in both models: low area under the heart rate response curve during TSST-G as well as low salivary alpha amylase level after TSST-G. Further, high muscle power, non-smoking, high extraversion, and low agreeableness were predictors of a favourable ANS response in either one of the two dependent variables. Good physical fitness, especially good aerobic endurance capacity, is an important protective factor against health

  13. Corticosterone and dehydroepiandrosterone in songbird plasma and brain: effects of season and acute stress

    PubMed Central

    Newman, Amy E. M.; Soma, Kiran K.

    2010-01-01

    Prolonged increases in plasma glucocorticoids can exacerbate neurodegeneration. In rats, these neurodegenerative effects can be reduced by dehydroepiandrosterone (DHEA), an androgen precursor with anti-glucocorticoid actions. In song sparrows, season and acute restraint stress affect circulating levels of corticosterone and DHEA, and the effects of stress differ in plasma collected from the brachial and jugular veins. Jugular plasma is an indirect index of the neural steroidal milieu. Here, we directly measured corticosterone and DHEA in several brain regions and jugular plasma, and examined the effects of season and acute restraint stress (30 min) (n = 571 samples). Corticosterone levels were up to 10× lower in brain than in jugular plasma. In contrast, DHEA levels were up to 5× higher in brain than in jugular plasma and were highest in the hippocampus. Corticosterone and DHEA concentrations were strongly seasonally regulated in plasma but, surprisingly, not seasonally regulated in brain. Acute stress increased corticosterone levels in plasma and brain, except during the molt, when stress unexpectedly decreased corticosterone levels in the hippocampus. Acute stress increased DHEA levels in plasma during the molt but had no effects on DHEA levels in brain. This is the first study to measure (i) corticosterone or DHEA levels in the brain of adult songbirds and (ii) seasonal changes in corticosterone or DHEA levels in the brain of any species. These results highlight several critical differences between systemic and local steroid concentrations and the difficulty of using circulating steroid levels to infer local steroid levels within the brain. PMID:19473242

  14. Acute Stress in Parents of Children Newly Diagnosed With Cancer

    PubMed Central

    Patiño-Fernández, Anna Maria; Pai, Ahna L.H.; Alderfer, Melissa; Hwang, Wei-Ting; Reilly, Anne; Kazak, Anne E.

    2010-01-01

    Objective Acute Stress Disorder (ASD) and subclinical symptoms of acute stress (SAS) may be a useful framework for understanding the psychological reactions of mothers and fathers of children newly diagnosed with a pediatric malignancy. Patients and Methods Mothers (N = 129) and fathers (N = 72) of 138 children newly diagnosed with cancer completed questionnaires assessing acute distress, anxiety, and family functioning. Demographic data were also gathered. Inclusion criteria were: a confirmed diagnosis of a pediatric malignancy in a child under the age of 18 years without prior chronic or life threatening illness and fluency in English or Spanish. Results Descriptive statistics and multiple linear regressions were used to examine predictors of SAS. Fifty-one percent (N = 66) of mothers and 40% (N = 29) of fathers met DSM-IV diagnostic criteria for ASD. The majority of the sample reported experiencing at least one SAS. General anxiety, but not family functioning, was a strong predictor of SAS in both mothers and fathers even after controlling for demographic characteristics. Conclusions Immediately following their child’s diagnosis of cancer, most mothers and fathers experience SAS, with a subsample meeting criteria for ASD. More anxious parents are at heightened risk of more intense reactions. The findings support the need for evidence-based psychosocial support at diagnosis and throughout treatment for families who are at risk for acute distress reactions. PMID:17514742

  15. Acute Heat Stress Changes Protein Expression in the Testes of a Broiler-Type Strain of Taiwan Country Chickens.

    PubMed

    Wang, Shih-Han; Cheng, Chuen-Yu; Chen, Chao-Jung; Chan, Hong-Lin; Chen, Hsin-Hsin; Tang, Pin-Chi; Chen, Chih-Feng; Lee, Yen-Pai; Huang, San-Yuan

    2018-03-19

    Heat stress leads to decreased fertility in roosters. This study investigated the global protein expression in response to acute heat stress in the testes of a broiler-type strain of Taiwan country chickens (TCCs). Twelve 45-week-old roosters were randomly allocated to the control group maintained at 25°C, and three groups subjected to acute heat stress at 38°C for 4 h, with 0, 2, and 6 h of recovery, respectively. Testis samples were collected for hematoxylin and eosin staining, apoptosis assay, and protein analysis. The results revealed 101 protein spots that differed significantly from the control following exposure to acute heat stress. The proteins that were differentially expressed participated mainly in protein metabolism and other metabolic processes, responses to stimuli, apoptosis, cellular organization, and spermatogenesis. Proteins that negatively regulate apoptosis were downregulated and proteins involved in autophagy and major heat shock proteins (HSP90α, HSPA5, and HSPA8) were upregulated in the testes of heat-stressed chickens. In conclusion, acute heat stress causes a change in protein expression in the testes of broiler-type B strain TCCs and may thus impair cell morphology, spermatogenesis, and apoptosis. The expression of heat shock proteins increased to attenuate the testicular injury induced by acute heat stress.

  16. Acute psychosocial stress and emotion regulation skills modulate empathic reactions to pain in others

    PubMed Central

    Buruck, Gabriele; Wendsche, Johannes; Melzer, Marlen; Strobel, Alexander; Dörfel, Denise

    2014-01-01

    Psychosocial stress affects resources for adequate coping with environmental demands. A crucial question in this context is the extent to which acute psychosocial stressors impact empathy and emotion regulation. In the present study, 120 participants were randomly assigned to a control group vs. a group confronted with the Trier Social Stress Test (TSST), an established paradigm for the induction of acute psychosocial stress. Empathy for pain as a specific subgroup of empathy was assessed via pain intensity ratings during a pain-picture task. Self-reported emotion regulation skills were measured as predictors using an established questionnaire. Stressed individuals scored significantly lower on the appraisal of pain pictures. A regression model was chosen to find variables that further predict the pain ratings. These findings implicate that acute psychosocial stress might impair empathic processes to observed pain in another person and the ability to accept one's emotion additionally predicts the empathic reaction. Furthermore, the ability to tolerate negative emotions modulated the relation between stress and pain judgments, and thus influenced core cognitive-affective functions relevant for coping with environmental challenges. In conclusion, our study emphasizes the necessity of reducing negative emotions in terms of empathic distress when confronted with pain of another person under psychosocial stress, in order to be able to retain pro-social behavior. PMID:24910626

  17. Acute Stress Symptoms in Children: Results From an International Data Archive

    PubMed Central

    Kassam-Adams, Nancy; Palmieri, Patrick A.; Rork, Kristine; Delahanty, Douglas L.; Kenardy, Justin; Kohser, Kristen L.; Landolt, Markus A.; Le Brocque, Robyne; Marsac, Meghan L.; Meiser-Stedman, Richard; Nixon, Reginald D. V.; Bui, Eric; McGrath, Caitlin

    2012-01-01

    Objective To describe the prevalence of acute stress disorder (ASD) symptoms and examine proposed DSM-5 symptom criteria in relation to concurrent functional impairment in children. Method From an international archive, datasets were identified which included assessment of acute traumatic stress reactions and concurrent impairment in children age 5 to 17. Data came from 15 studies conducted in the US, UK, Australia, and Switzerland with 1645 children. Dichotomized items were created to indicate the presence or absence of each of the 14 proposed ASD symptoms and functional impairment. The performance of a proposed diagnostic criterion (number of ASD symptoms required) was examined as a predictor of concurrent impairment. Results Each ASD symptom was endorsed by 14% to 51% of children; 41% reported clinically-relevant impairment. Children reported from 0 to 13 symptoms (mean = 3.6). Individual ASD symptoms were associated with greater likelihood of functional impairment. The DSM-5 proposed 8-symptom requirement was met by 202 (12.3%) children, and had low sensitivity (.25) in predicting concurrent clinically-relevant impairment. Requiring fewer symptoms (three to four) greatly improved sensitivity while maintaining moderate specificity. Conclusions This group of symptoms appears to capture aspects of traumatic stress reactions that can create distress and interfere with children’s ability to function in the acute post-trauma phase. Results provide a benchmark for comparison with adult samples; a smaller proportion of children met the 8-symptom criterion than reported for adults. Symptom requirements for the ASD diagnosis may need to be lowered to optimally identify children whose acute distress warrants clinical attention. PMID:22840552

  18. Acute Stress Impairs Inhibitory Control based on Individual Differences in Parasympathetic Nervous System Activity

    PubMed Central

    Roos, Leslie E.; Knight, Erik L.; Beauchamp, Kathryn G.; Berkman, Elliot T.; Faraday, Kelsie; Hyslop, Katie; Fisher, Philip A.

    2017-01-01

    Identifying environmental influences on inhibitory control (IC) may help promote positive behavioral and social adjustment. Although chronic stress is known to predict lower IC, the immediate effects of acute stress are unknown. The parasympathetic nervous system (PNS) may be a mechanism of the stress-IC link, given its psychophysiological regulatory role and connections to prefrontal brain regions critical to IC. We used a focused assessment of IC (the stop-signal task) to test whether an acute social stressor (the Trier Social Stress Test) affected participants’ pre- to post-IC performance (n = 58), compared to a control manipulation (n = 31). High frequency heart-rate variability was used as an index of PNS activity in response to the manipulation. Results indicated that stress impaired IC performance, blocking the practice effects observed in control participants. We also investigated the associations between PNS activity and IC; higher resting PNS activity predicted better pre-manipulation IC, and greater PNS stressor reactivity protected against the negative effects of stress on IC. Together, these results are the first to document the immediate effects of acute stress on IC and a phenotypic marker (PNS reactivity to stressors) of susceptibility to stress-induced IC impairment. This study suggests a new way to identify situations in which individuals are likely to exhibit IC vulnerability and related consequences such as impulsivity and risk taking behavior. Targeting PNS regulation may represent a novel target for IC-focused interventions. PMID:28268165

  19. Effect of acute and repeated restraint stress on glucose oxidation to CO2 in hippocampal and cerebral cortex slices.

    PubMed

    Torres, I L; Gamaro, G D; Silveira-Cucco, S N; Michalowski, M B; Corrêa, J B; Perry, M L; Dalmaz, C

    2001-01-01

    It has been suggested that glucocorticoids released during stress might impair neuronal function by decreasing glucose uptake by hippocampal neurons. Previous work has demonstrated that glucose uptake is reduced in hippocampal and cerebral cortex slices 24 h after exposure to acute stress, while no effect was observed after repeated stress. Here, we report the effect of acute and repeated restraint stress on glucose oxidation to CO2 in hippocampal and cerebral cortex slices and on plasma glucose and corticosterone levels. Male adult Wistar rats were exposed to restraint 1 h/day for 50 days in the chronic model. In the acute model there was a single exposure. Immediately or 24 h after stress, the animals were sacrificed and the hippocampus and cerebral cortex were dissected, sliced, and incubated with Krebs buffer, pH 7.4, containing 5 mM glucose and 0.2 microCi D-[U-14C] glucose. CO2 production from glucose was estimated. Trunk blood was also collected, and both corticosterone and glucose were measured. The results showed that corticosterone levels after exposure to acute restraint were increased, but the increase was smaller when the animals were submitted to repeated stress. Blood glucose levels increased after both acute and repeated stress. However, glucose utilization, measured as CO2 production in hippocampal and cerebral cortex slices, was the same in stressed and control groups under conditions of both acute and chronic stress. We conclude that, although stress may induce a decrease in glucose uptake, this effect is not sufficient to affect the energy metabolism of these cells.

  20. Effects of dark chocolate consumption on the prothrombotic response to acute psychosocial stress in healthy men.

    PubMed

    von Känel, R; Meister, R E; Stutz, M; Kummer, P; Arpagaus, A; Huber, S; Ehlert, U; Wirtz, P H

    2014-12-01

    Flavanoid-rich dark chocolate consumption benefits cardiovascular health, but underlying mechanisms are elusive. We investigated the acute effect of dark chocolate on the reactivity of prothrombotic measures to psychosocial stress. Healthy men aged 20-50 years (mean ± SD: 35.7 ± 8.8) were assigned to a single serving of either 50 g of flavonoid-rich dark chocolate (n=31) or 50 g of optically identical flavonoid-free placebo chocolate (n=34). Two hours after chocolate consumption, both groups underwent an acute standardised psychosocial stress task combining public speaking and mental arithmetic. We determined plasma levels of four stress-responsive prothrombotic measures (i. e., fibrinogen, clotting factor VIII activity, von Willebrand Factor antigen, fibrin D-dimer) prior to chocolate consumption, immediately before and after stress, and at 10 minutes and 20 minutes after stress cessation. We also measured the flavonoid epicatechin, and the catecholamines epinephrine and norepinephrine in plasma. The dark chocolate group showed a significantly attenuated stress reactivity of the hypercoagulability marker D-dimer (F=3.87, p=0.017) relative to the placebo chocolate group. Moreover, the blunted D-dimer stress reactivity related to higher plasma levels of the flavonoid epicatechin assessed before stress (F=3.32, p = 0.031) but not to stress-induced changes in catecholamines (p's=0.35). There were no significant group differences in the other coagulation measures (p's≥0.87). Adjustments for covariates did not alter these findings. In conclusion, our findings indicate that a single consumption of flavonoid-rich dark chocolate blunted the acute prothrombotic response to psychosocial stress, thereby perhaps mitigating the risk of acute coronary syndromes triggered by emotional stress.

  1. Repeated handling, restraint, or chronic crowding impair the hypothalamic-pituitary-adrenocortical response to acute restraint stress.

    PubMed

    Gadek-Michalska, A; Bugajski, J

    2003-09-01

    The purpose of the present study was to assess whether, and to what extent prior handling, restraint or social crowding stress during 3-10 days affects the hypothalamic-pituitary-adrenocortical (HPA) response to an acute short-lasting restraint stress. Also the effect of a feedback inhibitory mechanism of corticosterone in the impairment of HPA axis by these stressors was investigated. Male Wistar rats were pretreated with handling 1 min/day for 3-10 days, restraint 2 times daily for 3-7 days and crowding stress for 7 days before exposure to acute restraint stress in metal tubes for 10 min. Some group of rats received exogenous s.c. corticosterone either once 25 mg/kg or 2 times daily 10 mg/kg for 3-10 days before restraint stress. After the last restraint the rats were decapitated and their trunk blood was collected for the measurement of plasma ACTH and serum corticosterone levels. Handling for 3-7 days, restraint for 3-7 days, and crowding for 7 days and a single pretreatment with corticosterone--all significantly and to a similar extent inhibited the restraint stress-induced increase in ACTH and corticosterone secretion. Chronic pretreatment with corticosterone blunted the restraint stress-induced increase in HPA axis activity. These results indicate that repeated short-lasting stress induced by handling, restraint, or crowding potently attenuates the acute restraint stress-induced stimulatory action of the HPA axis. They also indicate adaptive action of moderate stress on the HPA axis response to acute stress. The results also suggest that a short-lasting hypersecretion of corticosterone during psychological stress may induce a prolonged feedback inhibition of the HPA axis activity. The attenuation of HPA axis response by prior handling has also obvious methodological implications.

  2. Acute stress and depression 3 days after vaginal delivery--observational, comparative study.

    PubMed

    Imsiragić, Azijada Srkalović; Begić, Drazen; Martić-Biocina, Sanja

    2009-06-01

    During the first month postpartum, 85% of women experience some form of mood disorders. The most common are: postpartum blues, non-psychotic postpartum depression, puerperal psychosis. Delivery of a child can be traumatic for some women. Several authors have found that women could get symptoms of one form of posttraumatic stress disorder (PTSD) after childbirth. However, etiology of established postpartum disorders is still unknown. The aim of this study is to detect symptoms of acute stress reaction and acute depressive state as a consequence of peripartal complications, as early as three days postpartum using Impact of Events Scale revised (IES-R) and the Edinburgh Postnatal Depression Scale (EPDS) questionnaires and to demonstrate their potential usage for the early detection of vulnerable mothers with greater risk to develop any of postpartum psychiatric disorder, including PTSD. For that purpose 103 subjects, without previous medical history of psychiatric illness, were included in the investigation. Long duration of delivery (> or = 12 h), very painful delivery, complication and illness of mother during and after delivery as a consequence of delivery, preterm delivery (before week 36) and/or illness of the child (as a consequence of delivery or congenital) are considered to be risk factors for acute stress reaction and acute depressive state after delivery. Sixty one out of 103 investigated mothers had one or more researched peripartal complications. A statistically significant difference has been found between the control (n=42) and the peripartal complications (n=61) groups in both the mean IES-R (4.67 +/- 5.43 and 13.50 +/- 14.12, respectively, p < 0.01) as well as in the mean EPDS (3.85 +/- 2.76 and 7.03 +/- 3.90, respectively, p < 0.01) scores. Additionally, while there were 4 cases of acute stress reactions and 3 cases of acute depressive state in the peripartal complications group there were no cases of these states in the control group. Based on our

  3. Development and Psychometric Evaluation of Child Acute Stress Measures in Spanish and English

    PubMed Central

    Kassam-Adams, Nancy; Gold, Jeffrey I.; Montaño, Zorash; Kohser, Kristen L.; Cuadra, Anai; Muñoz, Cynthia; Armstrong, F. Daniel

    2015-01-01

    Clinicians and researchers need tools for accurate early assessment of children’s acute stress reactions and acute stress disorder (ASD). There is a particular need for independently validated Spanish-language measures. The current study reports on 2 measures of child acute stress (a self-report checklist and a semi-structured interview), describing the development of the Spanish version of each measure and psychometric evaluation of both the Spanish and English versions. Children between the ages of 8 to 17 years who had experienced a recent traumatic event completed study measures in Spanish (n = 225) or in English (n = 254). Results provide support for reliability (internal consistency of the measures in both languages ranges from .83 to .89; cross-language reliability of the checklist is .93) and for convergent validity (with later PTSD symptoms, and with concurrent anxiety symptoms). Comparing checklist and interview results revealed a strong association between severity scores within the Spanish and English samples. Checklist-interview differences in evaluating the presence of ASD appear to be linked to different content coverage for dissociation symptoms. Future studies should further assess the impact of differing assessment modes, content coverage, and the use of these measures in children with diverse types of acute trauma exposure in English- and Spanish-speaking children. PMID:23371337

  4. Exposure to Acute Stress is Associated with Attenuated Sweet Taste

    PubMed Central

    al’Absi, Mustafa; Nakajima, Motohiro; Hooker, Stephanie; Wittmers, Larry; Cragin, Tiffany

    2011-01-01

    This study examined the effects of stress on taste perception. Participants (N = 38; 21 women) completed two laboratory sessions: one stress (public speaking, math, and cold pressor) and one control rest session. The taste perception test was conducted at the end of each session and included rating the intensity and pleasantness of sweet, salty, sour, and savory solutions at suprathreshold concentrations. Cardiovascular, hormonal, and mood measures were collected throughout the sessions. Participants showed the expected changes in cardiovascular, hormonal, and mood measures in response to stress. Reported intensity of the sweet solution was significantly lower on the stress day than on the rest day. Cortisol level post stress predicted reduced intensity of salt and sour, suggesting that stress-related changes in adrenocortical activity were related to reduced taste intensity. Results indicate that acute stress may alter taste perception, and ongoing research investigates the extent to which these changes mediate effects of stress on appetite. PMID:22091733

  5. Behavioral economic analysis of stress effects on acute motivation for alcohol.

    PubMed

    Owens, Max M; Ray, Lara A; MacKillop, James

    2015-01-01

    Due to issues of definition and measurement, the heavy emphasis on subjective craving in the measurement of acute motivation for alcohol and other drugs remains controversial. Behavioral economic approaches have increasingly been applied to better understand acute drug motivation, particularly using demand curve modeling via purchase tasks to characterize the perceived reinforcing value of the drug. This approach has focused on using putatively more objective indices of motivation, such as units of consumption, monetary expenditure, and price sensitivity. To extend this line of research, the current study used an alcohol purchase task to determine if, compared to a neutral induction, a personalized stress induction would increase alcohol demand in a sample of heavy drinkers. The stress induction significantly increased multiple measures of the reinforcing value of alcohol to the individual, including consumption at zero price (intensity), the maximum total amount of money spent on alcohol (Omax), the first price where consumption was reduced to zero (breakpoint), and the general responsiveness of consumption to increases in price (elasticity). These measures correlated only modestly with craving and mood. Self-reported income was largely unrelated to demand but moderated the influence of stress on Omax. Moderation based on CRH-BP genotype (rs10055255) was present for Omax, with T allele homozygotes exhibiting more pronounced increases in response to stress. These results provide further support for a behavioral economic approach to measuring acute drug motivation. The findings also highlight the potential relevance of income and genetic factors in understanding state effects on the perceived reinforcing value of alcohol. © Society for the Experimental Analysis of Behavior.

  6. Systemic response of the stony coral Pocillopora damicornis against acute cadmium stress.

    PubMed

    Zhou, Zhi; Yu, Xiaopeng; Tang, Jia; Wu, Yibo; Wang, Lingui; Huang, Bo

    2018-01-01

    Heavy metals have become one of the main pollutants in the marine environment and a major threat to the growth and reproduction of stony corals. In the present study, the density of symbiotic zooxanthellae, levels of crucial physiological activities and the transcriptome were investigated in the stony coral Pocillopora damicornis after the acute exposure to elevated cadmium concentration. The density of symbiotic zooxanthellae decreased significantly during 12-24h period, and reached lowest at 24h after acute cadmium stress. No significant changes were observed in the activity of glutathione S-transferase during the entire stress exposure. The activities of superoxide dismutase and catalase, and the concentration of glutathione decreased significantly, but the activation level of caspase3 increased significantly after cadmium exposure. Furthermore, transcriptome sequencing and bioinformatics analysis revealed 3538 significantly upregulated genes and 8048 significantly downregulated genes at 12h after the treatment. There were 12 overrepresented GO terms for significantly upregulated genes, mostly related to unfolded protein response, endoplasmic reticulum stress and apoptosis. In addition, a total of 32 GO terms were overrepresented for significantly downregulated genes, and mainly correlated with macromolecular metabolic processes. These results collectively suggest that acute cadmium stress could induce apoptosis by repressing the production of the antioxidants, elevating oxidative stress and activating the unfolded protein response. This cascade of reactions would result to the collapse of the coral-zooxanthella symbiosis and the expulsion of symbiotic zooxanthellae in the stony coral P. damicornis, ultimately leading to coral bleaching. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. P-CPA pretreatment reverses the changes in sleep and behavior following acute immobilization stress rats.

    PubMed

    Sinha, Rakesh Kumar

    2006-02-01

    The effects of p-CPA (para-chlorophenylalanine) pretreatment was studied on the sleep-wake parameters and patterns of behavioral activities in an animal model of acute immobilization stress. For the experiments, young male Charles Foster rats were divided into three groups, subjected to (i) acute immobilization stress for four hours on specially designed wooden boards, (ii) a similar model of acute immobilization stress after pretreatment of p-CPA (injected through i.p. route), and (iii) control rats (p-CPA untreated and unstressed). Three channels of electrographic signals, i.e., EEG (electroencephalogram), EOG (electrooculogram), and EMG (electromyogram) were recorded continuously for four hours for all three groups of rats to analyze the changes in sleep-wake stages. The assessment of behavior was performed just after the stress on separate groups of rats in Open-Field (OF) and Elevated Plus-Maze (EPM) apparatuses. The significant changes in total sleep time (P < 0.05), total time for rapid eye movement sleep (P < 0.01), and total time in wakefulness (P < 0.01) following acute immobilization stress were found reversed in the p-CPA (a serotonin inhibitor) pretreated group of rats. Simultaneously, the results of the present work also revealed that the changes in grooming behavior (P < 0.05) in OF and the total time spent on the center of EPM (P < 0.05) were observed altered in p-CPA pretreated group of rats.

  8. Differential gene expressions in testes of L2 strain Taiwan country chicken in response to acute heat stress.

    PubMed

    Wang, Shih-Han; Cheng, Chuen-Yu; Tang, Pin-Chi; Chen, Chih-Feng; Chen, Hsin-Hsin; Lee, Yen-Pai; Huang, San-Yuan

    2013-01-15

    Acute heat stress affects genes involved in spermatogenesis in mammals. However, there is apparently no elaborate research on the effects of acute heat stress on gene expression in avian testes. The purpose of this study was to investigate global gene expression in testes of the L2 strain of Taiwan country chicken after acute heat stress. Twelve roosters, 45 weeks old, were allocated into four groups, including control roosters kept at 25 °C, roosters subjected to 38 °C acute heat stress for 4 hours without recovery, with 2-hour recovery, and with 6-hour recovery, respectively. Testis samples were collected for RNA isolation and microarray analysis. Based on gene expression profiles, 169 genes were upregulated and 140 genes were downregulated after heat stress using a cutoff value of twofold or greater change. Based on gene ontology analysis, differentially expressed genes were mainly related to response to stress, transport, signal transduction, and metabolism. A functional network analysis displayed that heat shock protein genes and related chaperones were the major upregulated groups in chicken testes after acute heat stress. A quantitative real-time polymerase chain reaction analysis of mRNA expressions of HSP70, HSP90AA1, BAG3, SERPINB2, HSP25, DNAJA4, CYP3A80, CIRBP, and TAGLN confirmed the results of the microarray analysis. Because the HSP genes (HSP25, HSP70, and HSP90AA1) and the antiapoptotic BAG3 gene were dramatically altered in heat-stressed chicken testes, we concluded that these genes were important factors in the avian testes under acute heat stress. Whether these genes could be candidate genes for thermotolerance in roosters requires further investigation. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Stress versus temperature dependent activation energies in creep

    NASA Technical Reports Server (NTRS)

    Freed, A. D.; Raj, S. V.; Walker, K. P.

    1990-01-01

    The activation energy for creep at low stresses and elevated temperatures is lattice diffusion, where the rate controlling mechanism for deformation is dislocation climb. At higher stresses and intermediate temperatures, the rate controlling mechanism changes from that of dislocation climb to one of obstacle-controlled dislocation glide. Along with this change, there occurs a change in the activation energy. It is shown that a temperature-dependent Gibbs free energy does a good job of correlating steady-state creep data, while a stress-dependent Gibbs free energy does a less desirable job of correlating the same data. Applications are made to copper and a LiF-22 mol. percent CaF2 hypereutectic salt.

  10. Preliminary evidence that acute stress moderates basal testosterone's association with retaliatory behavior.

    PubMed

    Prasad, Smrithi; Narayanan, Jayanth; Lim, Vivien K G; Koh, Gerald C H; Koh, David S Q; Mehta, Pranjal H

    2017-06-01

    A contribution to a special issue on Hormones and Human Competition. Testosterone is theorized to increase retaliation after social provocation. However, empirical evidence in support of these theories is mixed. The present research investigated whether acute stress causally suppresses testosterone's association with retaliation. We also explored sex differences in behavioral responses to acute stress. Thirty-nine participants (51.28% male) were randomly assigned to a high- or low-stress condition. Then participants engaged in 20 one-shot rounds of the ultimatum game, which was used to assess retaliatory behavioral responses to unfair treatment. Participants provided two saliva samples to measure testosterone and cortisol concentrations - one sample before the stress manipulation, and the second after the ultimatum game (20minutes post-stressor). Results revealed a positive association between basal testosterone and retaliation in the low-stress condition, but not in the high-stress condition. Further, cortisol concentrations increased in the high- compared to the low-stress condition, and these cortisol changes moderated the association between basal testosterone and retaliation. The associations between basal testosterone and retaliation under varying levels of stress were similar in men and women. However, there was a sex difference in behavioral responses to the stress manipulation that was independent of testosterone. In women, the high-stress condition reduced retaliation compared to the low-stress condition, whereas in men the opposite pattern emerged. Collectively, this study (i) provides preliminary evidence that experimentally manipulated stress blocks basal testosterone's association with retaliation, and (ii) reveals a sex difference in retaliation under varying levels of stress. Discussion focuses on mechanisms, limitations, and the need for follow-up studies with larger sample sizes. Copyright © 2016 Elsevier Inc. All rights reserved.

  11. Antioxidant defense and oxidative stress in children with acute hepatitis A

    PubMed Central

    Popovic-Dragonjic, Lidija; Jovanovic, Maja; Vrbic, Miodrag; Konstantinovic, Ljiljana; Kostic, Velimir; Dragonjic, Ivan

    2011-01-01

    BACKGROUND AND OBJECTIVES: Published data on oxidative stress in children with acute hepatitis A are still very scarce. This study aims to evaluate the oxidant/antioxidant status of these patients. DESIGN AND SETTING: Prospective, case-control study, over 2.5 years in patients under hospitalized and ambulatory care. PATIENTS AND METHODS: The levels of a whole-blood antioxidant, reduced glutathione; and plasma antioxidants, β-carotene, retinol, ascorbic acid, α-tocopherol; and the biomarker of oxidative stress, malondialdehyde, were evaluated in 50 pediatric patients (age range, 5-16 years; 29 males and 21 females) with acute hepatitis A and in 50 healthy children as control subjects (age range, 5-16 years; 25 males and 25 females). RESULTS: Plasma levels of reduced glutathione, β-carotene, retinol, α-tocopherol and ascorbic acid were significantly lower, while malondialdehyde plasma levels were significantly increased in the patient group when compared to the controls (P<.0001 for all parameters). CONCLUSIONS: Our findings show that pediatric patients with acute hepatitis A were influenced by oxidative stress, resulting in significantly lower levels of plasma antioxidants and increased lipid peroxidation. In the absence of other therapeutic options, antioxidant vitamin supplements could be added to the therapy for these patients to help reestablish the oxidant status balance. Further investigations to confirm this suggestion are recommended. PMID:21623054

  12. Body temperature and mortality in patients with acute respiratory distress syndrome.

    PubMed

    Schell-Chaple, Hildy M; Puntillo, Kathleen A; Matthay, Michael A; Liu, Kathleen D

    2015-01-01

    Little is known about the relationship between body temperature and outcomes in patients with acute respiratory distress syndrome (ARDS). A better understanding of this relationship may provide evidence for fever suppression or warming interventions, which are commonly applied in practice. To examine the relationship between body temperature and mortality in patients with ARDS. Secondary analysis of body temperature and mortality using data from the ARDS Network Fluid and Catheter Treatment Trial (n = 969). Body temperature at baseline and on study day 2, primary cause of ARDS, severity of illness, and 90-day mortality were analyzed by using multiple logistic regression. Mean baseline temperature was 37.5°C (SD, 1.1°C; range, 27.2°C-40.7°C). At baseline, fever (≥ 38.3°C) was present in 23% and hypothermia (< 36°C) in 5% of the patients. Body temperature was a significant predictor of 90-day mortality after primary cause of ARDS and score on the Acute Physiology and Chronic Health Evaluation III were adjusted for. Higher temperature was associated with decreased mortality: for every 1°C increase in baseline temperature, the odds of death decreased by 15% (odds ratio, 0.85; 95% CI, 0.73-0.98, P = .03). When patients were divided into 5 temperature groups, mortality was lower with higher temperature (P for trend = .02). Early in ARDS, fever is associated with improved survival rates. Fever in the acute phase response to lung injury and its relationship to recovery may be an important factor in determining patients' outcome and warrants further study. ©2015 American Association of Critical-Care Nurses.

  13. Body Temperature and Mortality in Patients with Acute Respiratory Distress Syndrome

    PubMed Central

    Schell-Chaple, Hildy M.; Puntillo, Kathleen A.; Matthay, Michael A.; Liu, Kathleen D.

    2015-01-01

    Background Little is known about the relationship between body temperature and outcomes in patients with acute respiratory distress syndrome (ARDS). A better understanding of this relationship may provide evidence for fever suppression or warming interventions, which are commonly applied in practice. Objective To examine the relationship between body temperature and mortality in patients with ARDS. Methods Secondary analysis of body temperature and mortality using data from the ARDS Network Fluid and Catheter Treatment Trial (n =969). Body temperature at baseline and on study day 2, primary cause of ARDS, severity of illness, and 90-day mortality were analyzed by using multiple logistic regression. Results Mean baseline temperature was 37.5°C (SD, 1.1°C; range, 27.2°C-40.7°C). At baseline, fever (≥ 38.3°C) was present in 23% and hypothermia (< 36°C) in 5% of the patients. Body temperature was a significant predictor of 90-day mortality after primary cause of ARDS and score on the Acute Physiology and Chronic Health Evaluation III were adjusted for. Higher temperature was associated with decreased mortality: for every 1°C increase in baseline temperature, the odds of death decreased by 15% (odds ratio, 0.85; 95% CI, 0.73-0.98, P = .03). When patients were divided into 5 temperature groups, mortality was lower with higher temperature (P for trend=.02). Conclusions Early in ARDS, fever is associated with improved survival rates. Fever in the acute phase response to lung injury and its relationship to recovery may be an important factor in determining patients' outcome and warrants further study. PMID:25554550

  14. OSO paradigm--A rapid behavioral screening method for acute psychosocial stress reactivity in mice.

    PubMed

    Brzózka, M M; Unterbarnscheidt, T; Schwab, M H; Rossner, M J

    2016-02-09

    Chronic psychosocial stress is an important environmental risk factor for the development of psychiatric diseases. However, studying the impact of chronic psychosocial stress in mice is time consuming and thus not optimally suited to 'screen' increasing numbers of genetically manipulated mouse models for psychiatric endophenotypes. Moreover, many studies focus on restraint stress, a strong physical stressor with limited relevance for psychiatric disorders. Here, we describe a simple and a rapid method based on the resident-intruder paradigm to examine acute effects of mild psychosocial stress in mice. The OSO paradigm (open field--social defeat--open field) compares behavioral consequences on locomotor activity, anxiety and curiosity before and after exposure to acute social defeat stress. We first evaluated OSO in male C57Bl/6 wildtype mice where a single episode of social defeat reduced locomotor activity, increased anxiety and diminished exploratory behavior. Subsequently, we applied the OSO paradigm to mouse models of two schizophrenia (SZ) risk genes. Transgenic mice with neuronal overexpression of Neuregulin-1 (Nrg1) type III showed increased risk-taking behavior after acute stress exposure suggesting that NRG1 dysfunction is associated with altered affective behavior. In contrast, Tcf4 transgenic mice displayed a normal stress response which is in line with the postulated predominant contribution of TCF4 to cognitive deficits of SZ. In conclusion, the OSO paradigm allows for rapid screening of selected psychosocial stress-induced behavioral endophenotypes in mouse models of psychiatric diseases. Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.

  15. Mimicking acute and chronic stress exposure in naive beef steers alters the acute phase response (APR) associated with vaccination

    USDA-ARS?s Scientific Manuscript database

    This study was designed to determine the effect of an acute versus chronic stress model on the APR associated with vaccination in naïve beef steers. Steers (n=32; 209 +/- 8 kg) were blocked by body weight and assigned to 1 of 3 treatments: 1) Chronic stress (CHR), 0.5 mg/kg body weight dexamethasone...

  16. Chronic Desipramine Prevents Acute Stress-Induced Reorganization of Medial Prefrontal Cortex Architecture by Blocking Glutamate Vesicle Accumulation and Excitatory Synapse Increase

    PubMed Central

    Treccani, Giulia; Liebenberg, Nico; Chen, Fenghua; Popoli, Maurizio; Wegener, Gregers; Nyengaard, Jens Randel

    2015-01-01

    Background: Although a clear negative influence of chronic exposure to stressful experiences has been repeatedly demonstrated, the outcome of acute stress on key brain regions has only just started to be elucidated. Although it has been proposed that acute stress may produce enhancement of brain plasticity and that antidepressants may prevent such changes, we still lack ultrastructural evidence that acute stress-induced changes in neurotransmitter physiology are coupled with structural synaptic modifications. Methods: Rats were pretreated chronically (14 days) with desipramine (10mg/kg) and then subjected to acute foot-shock stress. By means of serial section electron microscopy, the structural remodeling of medial prefrontal cortex glutamate synapses was assessed soon after acute stressor cessation and stress hormone levels were measured. Results: Foot-shock stress induced a remarkable increase in the number of docked vesicles and small excitatory synapses, partially and strongly prevented by desipramine pretreatment, respectively. Acute stress-induced corticosterone elevation was not affected by drug treatment. Conclusions: Since desipramine pretreatment prevented the stress-induced structural plasticity but not the hormone level increase, we hypothesize that the preventing action of desipramine is located on pathways downstream of this process and/or other pathways. Moreover, because enhancement of glutamate system remodeling may contribute to overexcitation dysfunctions, this aspect could represent a crucial component in the pathophysiology of stress-related disorders. PMID:25522419

  17. Eye surface temperature detects stress response in budgerigars (Melopsittacus undulatus).

    PubMed

    Ikkatai, Yuko; Watanabe, Shigeru

    2015-08-05

    Previous studies have suggested that stressors not only increase body core temperature but also body surface temperature in many animals. However, it remains unclear whether surface temperature could be used as an alternative to directly measure body core temperature, particularly in birds. We investigated whether surface temperature is perceived as a stress response in budgerigars. Budgerigars have been used as popular animal models to investigate various neural mechanisms such as visual perception, vocal learning, and imitation. Developing a new technique to understand the basic physiological mechanism would help neuroscience researchers. First, we found that cloacal temperature correlated with eye surface temperature. Second, eye surface temperature increased after handling stress. Our findings suggest that eye surface temperature is closely related to cloacal temperature and that the stress response can be measured by eye surface temperature in budgerigars.

  18. Role of Paraoxonase 1 Activity and Oxidative/Antioxidative Stress Markers in Patients with Acute Cerebral Infarction.

    PubMed

    Zhu, Hui; Zhao, Teng; Liu, Jingyao

    2018-06-01

    Paraoxonase1 (PON1) is an antioxidant which confers antioxidant properties to high-density lipoprotein (HDL) and prevents low-density lipoprotein (LDL) oxidation. The purpose of this study was to evaluate the activities of PON1 and oxidative/antioxidative stress markers in acute cerebral infarction. In this study, 161 patients diagnosed with acute cerebral infarction and 161 gender- and age-matched healthy controls were recruited. Based on the clinicoradiological profiles, the patients were further classified into two groups: lacunar infarction group and large-artery atherosclerosis group. We measured the individual lipid status parameters, oxidative and antioxidative stress status parameters, and PON1 activity. Serum total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and oxidative stress parameters in patients with acute cerebral infarction were significantly higher than those in the normal controls (p < 0.05). High-density lipoprotein cholesterol (HDL-C) level, PON1 activity, superoxide dismutase (SOD) activity, and antioxidative stress parameters in patients were lower than in the normal controls (p < 0.05). Superoxide anion (O2-), malondialdehyde (MDA), and PON1 levels in the lacunar infarction group were lower than in the large-artery atherosclerosis group (p < 0.05). Oxidative stress markers and PON1 activity are sensitive indicators of acute cerebral infarction. Our findings suggest a severely impaired antioxidative protection mechanism in these patients. Our study provides new insights into the pathophysiological mechanisms of acute cerebral infarction, which may also provide new therapeutic targets for ischemic cerebrovascular diseases.

  19. Exposure to acute stress is associated with attenuated sweet taste.

    PubMed

    Al'Absi, Mustafa; Nakajima, Motohiro; Hooker, Stephanie; Wittmers, Larry; Cragin, Tiffany

    2012-01-01

    This study examined the effects of stress on taste perception. Participants (N = 38; 21 women) completed two laboratory sessions: one stress (public speaking, math, and cold pressor) and one control rest session. The taste perception test was conducted at the end of each session and included rating the intensity and pleasantness of sweet, salty, sour, and savory solutions at suprathreshold concentrations. Cardiovascular, hormonal, and mood measures were collected throughout the sessions. Participants showed the expected changes in cardiovascular, hormonal, and mood measures in response to stress. Reported intensity of the sweet solution was significantly lower on the stress day than on the rest day. Cortisol level poststress predicted reduced intensity of salt and sour, suggesting that stress-related changes in adrenocortical activity were related to reduced taste intensity. Results indicate that acute stress may alter taste perception, and ongoing research investigates the extent to which these changes mediate effects of stress on appetite. Copyright © 2011 Society for Psychophysiological Research.

  20. The effect of dietary folic acid on biochemical parameters and gene expression of three heat shock proteins (HSPs) of blunt snout bream (Megalobrama amblycephala) fingerling under acute high temperature stress.

    PubMed

    Sesay, Daniella Fatmata; Habte-Tsion, Habte-Michael; Zhou, Qunlan; Ren, Mingchun; Xie, Jun; Liu, Bo; Chen, Ruli; Pan, Liangkun

    2017-08-01

    The effects of dietary folic acid on biochemical parameters and gene expression of three heat shock proteins (HSPs) of blunt snout bream (Megalobrama amblycephala) fingerling under acute high temperature stress. Six dietary folic acid groups (0.0, 0.5, 1.0, 2.0, 5.0, and 10.0) mg/kg diets were designed and assigned into 18 tanks in three replicates each (300 l/tank) and were administered for 10 weeks in a re-circulated water system. The fingerlings with an initial weight of 27.0 ± 0.03 g were fed with their respective diets four times daily. At the end of the experiment, samples were collected before challenge, 0, 24, 72 h, and 7 days. Serum total protein (TP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), cortisol, glucose, complement C3 (C3), complement C4 (C4, immunoglobulin M (IgM) hepatic superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and the expression of heat shock protein 60 (HSP60), 70 (HSP70), and 90 (HSP90) were studied. The results showed that fish fed with dietary folic acid between 1.0, 2.0, and 5.0 mg/kg significantly (P < 0.05) increased serum TP, C3, C4 hepatic SOD, CAT, and the expression of HSP60, HSP70, and HSP90 before and after temperature challenge of 32 °C. Also, serum ALP, cortisol, glucose, and hepatic MDA were significantly (P < 0.05) reduced by supplementation of dietary folic acid level 1.0, 2.0, and 5.0 mg/kg before and after the same temperature challenge of 32 °C. Before stress, 0, 24, 72 h, and 7 days significantly (P < 0.05) affects serum biochemical parameters, immune and antioxidant capacities, and expression level of three HSPs. Furthermore, there was no statistical evidence to show that dietary folic acid inclusion level and temperature duration have significant interactive effect on serum biochemical parameters, antioxidant parameters, and gene expression level (P > 0.05) of the three HSPs. However, there were statistical significant

  1. Individual differences in early adolescents' latent trait cortisol (LTC): Relation to recent acute and chronic stress.

    PubMed

    Stroud, Catherine B; Chen, Frances R; Doane, Leah D; Granger, Douglas A

    2016-08-01

    Research suggests that environmental stress contributes to health by altering the regulation of the hypothalamic pituitary adrenal (HPA) axis. Recent evidence indicates that early life stress alters trait indicators of HPA axis activity, but whether recent stress alters such indicators is unknown. Using objective contextual stress interviews with adolescent girls and their mothers, we examined the impact of recent acute and chronic stress occurring during the past year on early adolescent girls' latent trait cortisol (LTC) level. We also examined whether associations between recent stress and LTC level: a) varied according to the interpersonal nature and controllability of the stress; and b) remained after accounting for the effect of early life stress. Adolescents (n=117;M age=12.39years) provided salivary cortisol samples three times a day (waking, 30min post-waking and bedtime) over 3days. Results indicated that greater recent interpersonal acute stress and greater recent independent (i.e., uncontrollable) acute stress were each associated with a higher LTC level, over and above the effect of early adversity. In contrast, greater recent chronic stress was associated with a lower LTC level. Findings were similar in the overall sample and a subsample of participants who strictly adhered to the timed schedule of saliva sample collection. Implications for understanding the impact of recent stress on trait-like individual differences in HPA axis activity are discussed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Derivation and test of elevated temperature thermal-stress-free fastener concept

    NASA Technical Reports Server (NTRS)

    Sawyer, J. W.; Blosser, M. L.; Mcwithey, R. R.

    1985-01-01

    Future aerospace vehicles must withstand high temperatures and be able to function over a wide temperature range. New composite materials are being developed for use in designing high-temperature lightweight structures. Due to the difference between coefficients of thermal expansion for the new composite materials and conventional high-temperature metallic fasteners, innovative joining techniques are needed to produce tight joints at all temperatures without excessive thermal stresses. A thermal-stress-free fastening technique is presented that can be used to provide structurally tight joints at all temperatures even when the fastener and joined materials have different coefficients of thermal expansion. The derivation of thermal-stress-free fasteners and joint shapes is presented for a wide variety of fastener materials and materials being joined together. Approximations to the thermal-stress-free shapes that result in joints with low-thermal-stresses and that simplify the fastener/joint shape are discussed. The low-thermal-stress fastener concept is verified by thermal and shear tests in joints using oxide-dispersion-strengthened alloy fasteners in carbon-carbon material. The test results show no evidence of thermal stress damage for temperatures up to 2000 F and the resulting joints carried shear loads at room temperature typical of those for conventional joints.

  3. The relationship between personality and the response to acute psychological stress.

    PubMed

    Xin, Yuanyuan; Wu, Jianhui; Yao, Zhuxi; Guan, Qing; Aleman, André; Luo, Yuejia

    2017-12-04

    The present study examined the relationship between personality traits and the response to acute psychological stress induced by a standardized laboratory stress induction procedure (the Trier Social Stress Test, TSST). The stress response was measured with a combination of cardiovascular reactivity, hypothalamic-pituitary-adrenal axis reactivity, and subjective affect (including positive affect, negative affect and subjective controllability) in healthy individuals. The Generalized Estimating Equations (GEE) approach was applied to account for the relationship between personality traits and stress responses. Results suggested that higher neuroticism predicted lower heart rate stress reactivity, lower cortisol stress response, more decline of positive affect and lower subjective controllability. Individuals higher in extraversion showed smaller cortisol activation to stress and less increase of negative affect. In addition, higher openness score was associated with lower cortisol stress response. These findings elucidate that neuroticism, extraversion and openness are important variables associated with the stress response and different dimensions of personality trait are associated with different aspects of the stress response.

  4. Lower Electrodermal Activity to Acute Stress in Caregivers of People with Autism Spectrum Disorder: An Adaptive Habituation to Stress

    ERIC Educational Resources Information Center

    Ruiz-Robledillo, Nicolás; Moya-Albiol, Luis

    2015-01-01

    Caring for a relative with autism spectrum disorder (ASD) entails being under chronic stress that could alter body homeostasis. Electrodermal activity (EDA) is an index of the sympathetic activity of the autonomic nervous system related to emotionality and homeostasis. This study compares EDA in response to acute stress in the laboratory between…

  5. Effects of chronic plus acute prolonged stress on measures of coping style, anxiety, and evoked HPA-axis reactivity.

    PubMed

    Roth, Megan K; Bingham, Brian; Shah, Aparna; Joshi, Ankur; Frazer, Alan; Strong, Randy; Morilak, David A

    2012-11-01

    Exposure to psychological trauma is the precipitating factor for PTSD. In addition, a history of chronic or traumatic stress exposure is a predisposing risk factor. We have developed a Chronic plus Acute Prolonged Stress (CAPS) treatment for rats that models some of the characteristics of stressful events that can lead to PTSD in humans. We have previously shown that CAPS enhances acute fear responses and impairs extinction of conditioned fear. Further, CAPS reduced the expression of glucocorticoid receptors in the medial prefrontal cortex. In this study we examined the effects of CAPS exposure on behavioral stress coping style, anxiety-like behaviors, and acute stress reactivity of the hypothalamic-pituitary-adrenal (HPA) axis. Male Sprague-Dawley rats were exposed to CAPS treatment, consisting of chronic intermittent cold stress (4 °C, 6 h/day, 14 days) followed on day 15 by a single 1-h session of sequential acute stressors (social defeat, immobilization, swim). After CAPS or control treatment, different groups were tested for shock probe defensive burying, novelty suppressed feeding, or evoked activation of adrenocorticotropic hormone (ACTH) and corticosterone release by an acute immobilization stress. CAPS resulted in a decrease in active burying behavior and an increase in immobility in the shock probe test. Further, CAPS-treated rats displayed increases in the latency to feed in the novelty suppressed feeding test, despite an increase in food intake in the home cage. CAPS treatment also reduced the HPA response to a subsequent acute immobilization stress. These results further validate CAPS treatment as a rat model of relevance to PTSD, and together with results reported previously, suggest that CAPS impairs fear extinction, shifts coping behavior from an active to a more passive strategy, increases anxiety, and alters HPA reactivity, resembling many aspects of human PTSD. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Obesity-Induced Endoplasmic Reticulum Stress Causes Lung Endothelial Dysfunction and Promotes Acute Lung Injury.

    PubMed

    Shah, Dilip; Romero, Freddy; Guo, Zhi; Sun, Jianxin; Li, Jonathan; Kallen, Caleb B; Naik, Ulhas P; Summer, Ross

    2017-08-01

    Obesity is a significant risk factor for acute respiratory distress syndrome. The mechanisms underlying this association are unknown. We recently showed that diet-induced obese mice exhibit pulmonary vascular endothelial dysfunction, which is associated with enhanced susceptibility to LPS-induced acute lung injury. Here, we demonstrate that lung endothelial dysfunction in diet-induced obese mice coincides with increased endoplasmic reticulum (ER) stress. Specifically, we observed enhanced expression of the major sensors of misfolded proteins, including protein kinase R-like ER kinase, inositol-requiring enzyme α, and activating transcription factor 6, in whole lung and in primary lung endothelial cells isolated from diet-induced obese mice. Furthermore, we found that primary lung endothelial cells exposed to serum from obese mice, or to saturated fatty acids that mimic obese serum, resulted in enhanced expression of markers of ER stress and the induction of other biological responses that typify the lung endothelium of diet-induced obese mice, including an increase in expression of endothelial adhesion molecules and a decrease in expression of endothelial cell-cell junctional proteins. Similar changes were observed in lung endothelial cells and in whole-lung tissue after exposure to tunicamycin, a compound that causes ER stress by blocking N-linked glycosylation, indicating that ER stress causes endothelial dysfunction in the lung. Treatment with 4-phenylbutyric acid, a chemical protein chaperone that reduces ER stress, restored vascular endothelial cell expression of adhesion molecules and protected against LPS-induced acute lung injury in diet-induced obese mice. Our work indicates that fatty acids in obese serum induce ER stress in the pulmonary endothelium, leading to pulmonary endothelial cell dysfunction. Our work suggests that reducing protein load in the ER of pulmonary endothelial cells might protect against acute respiratory distress syndrome in obese

  7. Aged rats are hypo-responsive to acute restraint: implications for psychosocial stress in aging

    PubMed Central

    Buechel, Heather M.; Popovic, Jelena; Staggs, Kendra; Anderson, Katie L.; Thibault, Olivier; Blalock, Eric M.

    2013-01-01

    Cognitive processes associated with prefrontal cortex and hippocampus decline with age and are vulnerable to disruption by stress. The stress/stress hormone/allostatic load hypotheses of brain aging posit that brain aging, at least in part, is the manifestation of life-long stress exposure. In addition, as humans age, there is a profound increase in the incidence of new onset stressors, many of which are psychosocial (e.g., loss of job, death of spouse, social isolation), and aged humans are well-understood to be more vulnerable to the negative consequences of such new-onset chronic psychosocial stress events. However, the mechanistic underpinnings of this age-related shift in chronic psychosocial stress response, or the initial acute phase of that chronic response, have been less well-studied. Here, we separated young (3 month) and aged (21 month) male F344 rats into control and acute restraint (an animal model of psychosocial stress) groups (n = 9–12/group). We then assessed hippocampus-associated behavioral, electrophysiological, and transcriptional outcomes, as well as blood glucocorticoid and sleep architecture changes. Aged rats showed characteristic water maze, deep sleep, transcriptome, and synaptic sensitivity changes compared to young. Young and aged rats showed similar levels of distress during the 3 h restraint, as well as highly significant increases in blood glucocorticoid levels 21 h after restraint. However, young, but not aged, animals responded to stress exposure with water maze deficits, loss of deep sleep and hyperthermia. These results demonstrate that aged subjects are hypo-responsive to new-onset acute psychosocial stress, which may have negative consequences for long-term stress adaptation and suggest that age itself may act as a stressor occluding the influence of new onset stressors. PMID:24575039

  8. Cardiopulmonary Effects of Acute Stressful Exercise at Altitude of Individuals with Sickle Cell Trait (SCT)

    DTIC Science & Technology

    1989-06-01

    Annual Symposium on Blood. Stuttgart Germany: FK Schattauer Verlag, 1973; 91-94. Home M: Sickle cell anemia as a rheologic disease. Am J Med 1981; 70...AD___ AD-A222 948 CARDIOPULMONARY EFFECTS OF ACUTE STRESSFUL EXERCISE AT ALTITUDE OF INDIVIDUALS WITH SICKLE CELL TRAIT (SCT) FINAL REPORT Idelle M...Clawi’katiornj (U) Cardiopulmonlary Effects to Acute Stressful Exercise at Altitude of Individuals with - sickle Cell Trait (I1bAS) 12. PERSONAL. AUTHOR

  9. Acute stress blocks the caffeine-induced enhancement of contextual memory retrieval in mice.

    PubMed

    Pierard, Chistophe; Krazem, Ali; Henkous, Nadia; Decorte, Laurence; Béracochéa, Daniel

    2015-08-15

    This study investigated in mice the dose-effect of caffeine on memory retrieval in non-stress and stress conditions. C57 Bl/6 Jico mice learned two consecutive discriminations (D1 and D2) in a four-hole board which involved either distinct contextual (CSD) or similar contextual (SSD) cues. All mice received an i.p. injection of vehicle or caffeine (8, 16 or 32mg/kg) 30min before the test session. Results showed that in non-stress conditions, the 16mg/kg caffeine dose induced a significant enhancement of D1 performance in CSD but not in SSD. Hence, we studied the effect of an acute stress (electric footshocks) administered 15min before the test session on D1 performance in caffeine-treated mice. Results showed that stress significantly decreased D1 performance in vehicle-treated controls and the memory-enhancing effect induced by the 16mg/kg caffeine dose in non-stress condition is no longer observed. Interestingly, whereas caffeine-treated mice exhibited weaker concentrations of plasma corticosterone as compared to vehicles in non-stress condition, stress significantly increased plasma corticosterone concentrations in caffeine-treated mice which reached similar level to that of controls. Overall, the acute stress blocked both the endocrinological and memory retrieval enhancing effects of caffeine. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. 46 CFR 54.05-30 - Allowable stress values at low temperatures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Allowable stress values at low temperatures. 54.05-30... PRESSURE VESSELS Toughness Tests § 54.05-30 Allowable stress values at low temperatures. (a) The Coast... nonferrous materials at low temperature for the purpose of establishing allowable stress values for service...

  11. 46 CFR 54.05-30 - Allowable stress values at low temperatures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Allowable stress values at low temperatures. 54.05-30... PRESSURE VESSELS Toughness Tests § 54.05-30 Allowable stress values at low temperatures. (a) The Coast... nonferrous materials at low temperature for the purpose of establishing allowable stress values for service...

  12. 46 CFR 54.05-30 - Allowable stress values at low temperatures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 2 2012-10-01 2012-10-01 false Allowable stress values at low temperatures. 54.05-30... PRESSURE VESSELS Toughness Tests § 54.05-30 Allowable stress values at low temperatures. (a) The Coast... nonferrous materials at low temperature for the purpose of establishing allowable stress values for service...

  13. 46 CFR 54.05-30 - Allowable stress values at low temperatures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 2 2014-10-01 2014-10-01 false Allowable stress values at low temperatures. 54.05-30... PRESSURE VESSELS Toughness Tests § 54.05-30 Allowable stress values at low temperatures. (a) The Coast... nonferrous materials at low temperature for the purpose of establishing allowable stress values for service...

  14. 46 CFR 54.05-30 - Allowable stress values at low temperatures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 2 2013-10-01 2013-10-01 false Allowable stress values at low temperatures. 54.05-30... PRESSURE VESSELS Toughness Tests § 54.05-30 Allowable stress values at low temperatures. (a) The Coast... nonferrous materials at low temperature for the purpose of establishing allowable stress values for service...

  15. Cognitive benefit and cost of acute stress is differentially modulated by individual brain state

    PubMed Central

    Hermans, Erno J.; Fernández, Guillén

    2017-01-01

    Abstract Acute stress is associated with beneficial as well as detrimental effects on cognition in different individuals. However, it is not yet known how stress can have such opposing effects. Stroop-like tasks typically show this dissociation: stress diminishes speed, but improves accuracy. We investigated accuracy and speed during a stroop-like task of 120 healthy male subjects after an experimental stress induction or control condition in a randomized, counter-balanced cross-over design; we assessed brain–behavior associations and determined the influence of individual brain connectivity patterns on these associations, which may moderate the effect and help identify stress resilience factors. In the mean, stress was associated to increase in accuracy, but decrease in speed. Accuracy was associated to brain activation in a distributed set of brain regions overlapping with the executive control network (ECN) and speed to temporo-parietal activation. In line with a stress-related large-scale network reconfiguration, individuals showing an upregulation of the salience and down-regulation of the executive-control network under stress displayed increased speed, but decreased performance. In contrast, individuals who upregulate their ECN under stress show improved performance. Our results indicate that the individual large-scale brain network balance under acute stress moderates cognitive consequences of threat. PMID:28402480

  16. Cognitive benefit and cost of acute stress is differentially modulated by individual brain state.

    PubMed

    Kohn, Nils; Hermans, Erno J; Fernández, Guillén

    2017-07-01

    Acute stress is associated with beneficial as well as detrimental effects on cognition in different individuals. However, it is not yet known how stress can have such opposing effects. Stroop-like tasks typically show this dissociation: stress diminishes speed, but improves accuracy. We investigated accuracy and speed during a stroop-like task of 120 healthy male subjects after an experimental stress induction or control condition in a randomized, counter-balanced cross-over design; we assessed brain-behavior associations and determined the influence of individual brain connectivity patterns on these associations, which may moderate the effect and help identify stress resilience factors. In the mean, stress was associated to increase in accuracy, but decrease in speed. Accuracy was associated to brain activation in a distributed set of brain regions overlapping with the executive control network (ECN) and speed to temporo-parietal activation. In line with a stress-related large-scale network reconfiguration, individuals showing an upregulation of the salience and down-regulation of the executive-control network under stress displayed increased speed, but decreased performance. In contrast, individuals who upregulate their ECN under stress show improved performance. Our results indicate that the individual large-scale brain network balance under acute stress moderates cognitive consequences of threat. © The Author (2017). Published by Oxford University Press.

  17. Mind-body interactions in the regulation of airway inflammation in asthma: A PET study of acute and chronic stress

    PubMed Central

    Rosenkranz, Melissa A.; Esnault, Stephane; Christian, Bradley T.; Crisafi, Gina; Gresham, Lauren K.; Higgins, Andrew T.; Moore, Mollie N.; Moore, Sarah M.; Weng, Helen Y.; Salk, Rachel H.; Busse, William W.; Davidson, Richard J.

    2016-01-01

    Background Psychological stress has long been recognized as a contributing factor to asthma symptom expression and disease progression. Yet, the neural mechanisms that underlie this relationship have been largely unexplored in research addressing the pathophysiology and management of asthma. Studies that have examined the mechanisms of this relationship in the periphery suggest that it is the superimposition of acute stress on top of chronic stress that is of greatest concern for airway inflammation. Methods We compared asthmatic individuals with high and low levels of chronic life stress in their neural and peripheral physiological responses to the Trier Social Stress Test and a matched control task. We used FDG-PET to measure neural activity during performance of the two tasks. We used both circulating and airway-specific markers of asthma-related inflammation to assess the impact of acute stress in these two groups. Results Asthmatics under chronic stress had a larger HPA-axis response to an acute stressor, which failed to show the suppressive effects on inflammatory markers observed in those with low chronic stress. Moreover, our PET data suggest that greater activity in the anterior insula during acute stress may reflect regulation of the effect of stress on inflammation. In contrast, greater activity in the mid-insula and perigenual anterior cingulate seems to reflect greater reactivity and was associated with greater airway inflammation, a more robust alpha amylase response, and a greater stress-induced increase in proinflammatory cytokine mRNA expression in airway cells. Conclusions Acute stress is associated with increases in markers of airway inflammation in asthmatics under chronic stress. This relationship may be mediated by interactions between the insula and anterior cingulate cortex, that determine the salience of environmental cues, as well as descending regulatory influence of inflammatory pathways in the periphery. PMID:27039241

  18. Mind-body interactions in the regulation of airway inflammation in asthma: A PET study of acute and chronic stress.

    PubMed

    Rosenkranz, Melissa A; Esnault, Stephane; Christian, Bradley T; Crisafi, Gina; Gresham, Lauren K; Higgins, Andrew T; Moore, Mollie N; Moore, Sarah M; Weng, Helen Y; Salk, Rachel H; Busse, William W; Davidson, Richard J

    2016-11-01

    Psychological stress has long been recognized as a contributing factor to asthma symptom expression and disease progression. Yet, the neural mechanisms that underlie this relationship have been largely unexplored in research addressing the pathophysiology and management of asthma. Studies that have examined the mechanisms of this relationship in the periphery suggest that it is the superimposition of acute stress on top of chronic stress that is of greatest concern for airway inflammation. We compared asthmatic individuals with high and low levels of chronic life stress in their neural and peripheral physiological responses to the Trier Social Stress Test and a matched control task. We used FDG-PET to measure neural activity during performance of the two tasks. We used both circulating and airway-specific markers of asthma-related inflammation to assess the impact of acute stress in these two groups. Asthmatics under chronic stress had a larger HPA-axis response to an acute stressor, which failed to show the suppressive effects on inflammatory markers observed in those with low chronic stress. Moreover, our PET data suggest that greater activity in the anterior insula during acute stress may reflect regulation of the effect of stress on inflammation. In contrast, greater activity in the mid-insula and perigenual anterior cingulate seems to reflect greater reactivity and was associated with greater airway inflammation, a more robust alpha amylase response, and a greater stress-induced increase in proinflammatory cytokine mRNA expression in airway cells. Acute stress is associated with increases in markers of airway inflammation in asthmatics under chronic stress. This relationship may be mediated by interactions between the insula and anterior cingulate cortex, that determine the salience of environmental cues, as well as descending regulatory influence of inflammatory pathways in the periphery. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Expression Characterization of Stress Genes Under High and Low Temperature Stresses in the Pacific Oyster, Crassostrea gigas.

    PubMed

    Zhu, Qihui; Zhang, Linlin; Li, Li; Que, Huayong; Zhang, Guofan

    2016-04-01

    As a characteristic sessile inhabitant of the intertidal zone, the Pacific oyster Crassostrea gigas occupies one of the most physically stressful environments on earth. With high exposure to terrestrial conditions, oysters must tolerate broad fluctuations in temperature range. However, oysters' cellular and molecular responses to temperature stresses have not been fully characterized. Here, we analyzed oyster transcriptome data under high and low temperatures. We also identified over 30 key temperature stress-responsive candidate genes, which encoded stress proteins such as heat shock proteins and apoptosis-associated proteins. The expression characterization of these genes under short-term cold and hot environments (5 and 35 °C) and long-term cold environments (5 °C) was detected by quantitative real-time PCR. Most of these genes reached expression peaks during the recovery stage after 24 h of heat stress, and these genes were greatly induced around day 3 in long-term cold stress while responded little to short-term cold stress. In addition, in the second heat stress after 2 days of recovery, oysters showed milder expression in these genes and a lower mortality rate, which indicated the existence of plasticity in the oyster's response to heat stress. We confirmed that homeostatic flexibility and anti-apoptosis might be crucial centers of temperature stress responses in oysters. Furthermore, we analyzed stress gene families in 11 different species and found that the linage-specific expansion of stress genes might be implicated in adaptive evolution. These results indicated that both plasticity and evolution played an important role in the stress response adaptation of oysters.

  20. Acute stress affects free recall and recognition of pictures differently depending on age and sex.

    PubMed

    Hidalgo, Vanesa; Pulopulos, Matias M; Puig-Perez, Sara; Espin, Laura; Gomez-Amor, Jesus; Salvador, Alicia

    2015-10-01

    Little is known about age differences in the effects of stress on memory retrieval. Our aim was to perform an in-depth examination of acute psychosocial stress effects on memory retrieval, depending on age and sex. For this purpose, data from 52 older subjects (27 men and 25 women) were reanalyzed along with data from a novel group of 50 young subjects (26 men and 24 women). Participants were exposed to an acute psychosocial stress task (Trier Social Stress Test) or a control task. After the experimental manipulation, the retrieval of positive, negative and neutral pictures learned the previous day was tested. As expected, there was a significant response to the exposure to the stress task, but the older participants had a lower cortisol response to TSST than the younger ones. Stress impaired free recall of emotional (positive and negative) and neutral pictures only in the group of young men. Also in this group, correlation analyses showed a marginally significant association between cortisol and free recall. However, exploratory analyses revealed only a negative relationship between the stress-induced cortisol response and free recall of negative pictures. Moreover, stress impaired recognition memory of positive pictures in all participants, although this effect was not related to the cortisol or alpha-amylase response. These results indicate that both age and sex are critical factors in acute stress effects on specific aspects of long-term memory retrieval of emotional and neutral material. They also point out that more research is needed to better understand their specific role. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Acute stress symptoms in children: results from an international data archive.

    PubMed

    Kassam-Adams, Nancy; Palmieri, Patrick A; Rork, Kristine; Delahanty, Douglas L; Kenardy, Justin; Kohser, Kristen L; Landolt, Markus A; Le Brocque, Robyne; Marsac, Meghan L; Meiser-Stedman, Richard; Nixon, Reginald D V; Bui, Eric; McGrath, Caitlin

    2012-08-01

    To describe the prevalence of acute stress disorder (ASD) symptoms and to examine proposed DSM-5 symptom criteria in relation to concurrent functional impairment in children and adolescents. From an international archive, datasets were identified that included assessment of acute traumatic stress reactions and concurrent impairment in children and adolescents 5 to 17 years of age. Data came from 15 studies conducted in the United States, United Kingdom, Australia, and Switzerland and included 1,645 children and adolescents. Dichotomized items were created to indicate the presence or absence of each of the 14 proposed ASD symptoms and functional impairment. The performance of a proposed diagnostic criterion (number of ASD symptoms required) was examined as a predictor of concurrent impairment. Each ASD symptom was endorsed by 14% to 51% of children and adolescents; 41% reported clinically relevant impairment. Children and adolescents reported from 0 to 13 symptoms (mean = 3.6). Individual ASD symptoms were associated with greater likelihood of functional impairment. The DSM-5 proposed eight-symptom requirement was met by 202 individuals (12.3%) and had low sensitivity (0.25) in predicting concurrent clinically relevant impairment. Requiring fewer symptoms (three to four) greatly improved sensitivity while maintaining moderate specificity. This group of symptoms appears to capture aspects of traumatic stress reactions that can create distress and interfere with children's and adolescents' ability to function in the acute post-trauma phase. Results provide a benchmark for comparison with adult samples; a smaller proportion of children and adolescents met the eight-symptom criterion than reported for adults. Symptom requirements for the ASD diagnosis may need to be lowered to optimally identify children and adolescents whose acute distress warrants clinical attention. Copyright © 2012 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All

  2. Comprehensive endocrine response to acute stress in the bottlenose dolphin from serum, blubber, and feces.

    PubMed

    Champagne, Cory D; Kellar, Nicholas M; Trego, Marisa L; Delehanty, Brendan; Boonstra, Rudy; Wasser, Samuel K; Booth, Rebecca K; Crocker, Daniel E; Houser, Dorian S

    2018-05-29

    Several hormones are potential indicators of stress in free-ranging animals and provide information on animal health in managed-care settings. In response to stress, glucocorticoids (GC, e.g. cortisol) first appear in circulation but are later incorporated into other tissues (e.g. adipose) or excreted in feces or urine. These alternative matrices can be sampled remotely, or by less invasive means, than required for blood collection and are especially valuable in highly mobile species, like marine mammals. We characterized the timing and magnitude of several hormones in response to a stressor in bottlenose dolphins (Tursiops truncatus) and the subsequent incorporation of cortisol into blubber, and its metabolites excreted in feces. We evaluated the endocrine response to an acute stressor in bottlenose dolphins under managed care. We used a standardized stress protocol where dolphins voluntarily beached onto a padded platform and remained out of water for two hours; during the stress test blood samples were collected every 15 min and blubber biopsies were collected every hour (0, 60, and 120 min). Each subject was studied over five days: voluntary blood samples were collected on each of two days prior to the stress test; 1 and 2 h after the conclusion of the out-of-water stress test; and on the following two days after the stress test. Fecal samples were collected daily, each afternoon. The acute stressor resulted in increases in circulating ACTH, cortisol, and aldosterone during the stress test, and each returned to baseline levels within 2 h of the dolphin's return to water. Both cortisol and aldosterone concentrations were correlated with ACTH, suggesting both corticosteroids are at least partly regulated by ACTH. Thyroid hormone concentrations were generally unaffected by the acute stressor. Blubber cortisol increased during the stress test, and fecal GC excretion was elevated on the day of the stress test. We found that GCs in bottlenose dolphins can

  3. Acute stress impairs the retrieval of extinction memory in humans

    PubMed Central

    Raio, Candace M.; Brignoni-Perez, Edith; Goldman, Rachel; Phelps, Elizabeth A.

    2014-01-01

    Extinction training is a form of inhibitory learning that allows an organism to associate a previously aversive cue with a new, safe outcome. Extinction does not erase a fear association, but instead creates a competing association that may or may not be retrieved when a cue is subsequently encountered. Characterizing the conditions under which extinction learning is expressed is important to enhancing the treatment of anxiety disorders that rely on extinction-based exposure therapy as a primary treatment technique. The ventromedial prefrontal cortex, which plays an important role in the expression of extinction memory, has been shown to be functionally impaired after stress exposure. Further, recent research in rodents found that exposure to stress led to deficits in extinction retrieval, although this has yet to be tested in humans. To explore how stress might influence extinction retrieval in humans, participants underwent a differential aversive learning paradigm, in which one image was probabilistically paired with an aversive shock while the other image denoted safety. Extinction training directly followed, at which point reinforcement was omitted. A day later, participants returned to the lab and either completed an acute stress manipulation (i.e., cold pressor), or a control task, before undergoing an extinction retrieval test. Skin conductance responses and salivary cortisol concentrations were measured throughout each session as indices of fear arousal and neuroendocrine stress responses, respectively. The efficacy of our stress induction was established by observing significant increases in cortisol for the stress condition only. We examined extinction retrieval by comparing conditioned responses during the last trial of extinction (day 1) with that of the first trial of re-extinction (day 2). Groups did not differ on initial fear acquisition or extinction, however, one day later participants in the stress group (n = 27) demonstrated significantly less

  4. Acute Alcohol Modulates Cardiac Function as PI3K/Akt Regulates Oxidative Stress

    PubMed Central

    Umoh, Nsini A.; Walker, Robin K.; Al-Rubaiee, Mustafa; Jeffress, Miara A.; Haddad, Georges E.

    2015-01-01

    Background Clinical manifestations of alcohol abuse on the cardiac muscle include defective contractility with the development of heart failure. Interestingly, low alcohol consumption has been associated with reduced risk of cardiovascular disease. Although several hypotheses have been postulated for alcoholic cardiomyopathy and for the low-dose beneficial cardiovascular effects, the precise mechanisms and mediators remain largely undefined. We hypothesize that modulation of oxidative stress by PI3K/Akt plays a key role in the cardiac functional outcome to acute alcohol exposure. Methods Thus, acutely exposed rat cardiac tissue and cardiocytes to low (LA: 5 mM), moderate (MA: 25 mM), and high (HA: 100 mM) alcohol were assessed for markers of oxidative stress in the presence and absence of PI3K/Akt activators (IGF-1 0.1 μM or constitutively active PI3K: Ad.BD110 transfection) or inhibitor (LY294002 1 μMor Akt-negative construct Ad.Akt(K179M) transfection). Results Acute LA reduced Akt, superoxide dismutase (SOD-3) and NFκB, ERK1, and p38 MAPK gene expression. Acute HA only increased that of SOD-3 and NFκB. These effects were generally inhibited by Ad.Akt(K179M) and enhanced with Ad.BD110 transfection. In parallel, LA reduced but HA enhanced Akt activity, which was reversed by IGF-1 and inhibited by Ad.Akt(K179M), respectively. Also, LA reduced caspase 3/7 activity and oxidative stress, while HA increased both. The former was blocked, while the latter effect was enhanced by Ad.Akt(K179M). The reverse was true with PI3K/Akt activation. This translated into reduced viability with HA, with no effect with LA. On the functional level, acute LA improved cardiac output and ejection fraction, mainly through increased stroke volume. This was accompanied with enhanced end-systolic pressure–volume relationship and preload recruitable stroke work. Opposite effect was recorded for HA. LA and HA in vivo functional effects were alleviated by LY and enhanced by IGF-1 treatment

  5. Stress versus temperature dependence of activation energies for creep

    NASA Technical Reports Server (NTRS)

    Freed, A. D.; Raj, S. V.; Walker, K. P.

    1992-01-01

    The activation energy for creep at low stresses and elevated temperatures is associated with lattice diffusion, where the rate controlling mechanism for deformation is dislocation climb. At higher stresses and intermediate temperatures, the rate controlling mechanism changes from dislocation climb to obstacle-controlled dislocation glide. Along with this change in deformation mechanism occurs a change in the activation energy. When the rate controlling mechanism for deformation is obstacle-controlled dislocation glide, it is shown that a temperature-dependent Gibbs free energy does better than a stress-dependent Gibbs free energy in correlating steady-state creep data for both copper and LiF-22mol percent CaF2 hypereutectic salt.

  6. Effect of acute psychological stress on prefrontal GABA concentration determined by proton magnetic resonance spectroscopy.

    PubMed

    Hasler, Gregor; van der Veen, Jan Willem; Grillon, Christian; Drevets, Wayne C; Shen, Jun

    2010-10-01

    Impaired function of the central gamma-aminobutyric acid (GABA) system, which provides the brain's major inhibitory pathways, is thought to play an important role in the pathophysiology of anxiety disorders. The effect of acute psychological stress on the human GABA-ergic system is still unknown, however. The purpose of this study was to determine the effect of acute stress on prefrontal GABA levels. A recently developed noninvasive magnetic resonance spectroscopy method was used to measure changes in the GABA concentration of the prefrontal cortex in 10 healthy human subjects during a threat-of-shock condition and during a safe condition (two sessions on different days). The main outcome measure was the mean GABA concentration within a 3×3×2-cm(3) voxel selected from the medial prefrontal cortex. Prefrontal GABA decreased by approximately 18% in the threat-of-shock condition relative to the safe condition. This reduction was specific to GABA, since the concentrations of N-acetyl-aspartate, choline-containing compounds, and glutamate/glutamine levels obtained in the same spectra did not change significantly. This result appeared compatible with evidence from preclinical studies in rodents, which showed rapid presynaptic down-regulation of GABA-ergic neurotransmission in response to acute psychological stress. The molecular mechanism and functional significance of this reduced inhibitory effect of acute psychological stress in relation to impaired GABA-ergic function in anxiety disorders merit further investigation.

  7. Acute Exercise and Oxidative Stress: CrossFit™ vs. Treadmill Bout

    PubMed Central

    Kliszczewicz, Brian; Quindry, C. John; Blessing, L. Daniel; Oliver, D. Gretchen; Esco, R. Michael; Taylor, J. Kyle

    2015-01-01

    CrossFit™, a popular high-intensity training modality, has been the subject of scrutiny, with concerns of elevated risk of injury and health. Despite these concerns empirical evidence regarding physiologic stresses including acute oxidative stress is lacking. Therefore, the purpose of this investigation was to examine the acute redox response to a CrossFit™ bout. Furthermore, these findings were compared to a high-intensity treadmill bout as a point of reference. Ten males 26.4 ± 2.7 yrs having three or more months of CrossFit™ experience participated in the present study. Blood plasma was collected at four time points: Pre-exercise (PRE), immediately-post-exercise (IPE), 1 hr-post (1-HP) and 2 hr-post (2-HP), to examine oxidative damage and antioxidant capacity. Regarding plasma oxidative damage, CrossFit™ and Treadmill elicited a time-dependent increase of lipid peroxides 1-HP (CrossFit™=+143%, Treadmill=+115%) and 2-HP (CrossFit™=+256%, Treadmill+167%). Protein Carbonyls were increased IPE in CF only (+5%), while a time-dependent decrease occurred 1-HP (CrossFit™=−16%, Treadmill=−8%) and 2-HP (CF=−16%, TM=−1%) compared to IPE. Regarding antioxidant capacity, Ferric Reducing Antioxidant Power also demonstrated a time-dependent increase within CrossFit™ and Treadmill: IPE (CrossFit™=+25%, Treadmill=+17%), 1-HP (CrossFit™=+26%, Treadmill=+4.8%), 2-HP (CrossFit™=+20%, Treadmill=+12%). Total Enzymatic Antioxidant Capacity showed a time-dependent decrease in IPE (CrossFit™=−10%, Treadmill=−12%), 1-HP (CrossFit™=−12%, Treadmill=−6%), 2-HP (CrossFit™=−7%, Treadmill=−11%). No trial-dependent differences were observed in any biomarker of oxidative stress. The CrossFit™ bout elicited an acute blood oxidative stress response comparable to a traditional bout of high-intensity treadmill running. Results also confirm that exercise intensity and the time course of exercise recovery influence oxidative responses. PMID:26557192

  8. A first insight into temperature stress-induced neuroendocrine and immunological changes in giant freshwater prawn, Macrobrachium rosenbergii.

    PubMed

    Chang, Chin-Chyuan; Jiang, Jia-Rong; Cheng, Winton

    2015-11-01

    Haemolymph norepinephrine (NE); total haemocyte count (THC); respiratory bursts (RBs); superoxide dismutase (SOD), phenoloxidase (PO), and phagocytic activity; and prophenoloxidase (proPO)-system-related genes (lipopolysaccharide- and β-1,3-glucan-binding protein: LGBP, proPO, peroxinectin: PE, and α2-macroglobulin: α2-M) in haemocytes of Macrobrachium rosenbergii were investigated after transferring them from 28 °C to 22 °C, 28 °C, and 34 °C respectively. The results revealed that haemolymph NE, hyaline cells (HCs), and PO activity per granulocyte increased from 30 to 120 min of exposure, and however, RBs and phagocytic activity significantly decreased from 30 to 120 min of exposure as well as granular cells (GCs), semigranular cells (SGCs), and SOD activity decreased from 60 to 120 min of exposure for the prawns subjected to temperature stress. The proPO-system-related gene expression markedly increased with 60-120 min of exposure for the prawns transferred from 28 °C to 22 °C and 34 °C, except α2M at 120 min. These results provide a first insight into the effects of temperature stress on haemolymph NE level and immune functions in prawns and suggest that temperature-stress-induced acute modulation in immunity is associated with the release of haemolymph NE in M. rosenbergii. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Acute psychosocial stress and everyday moral decision-making in young healthy men: The impact of cortisol.

    PubMed

    Singer, Nina; Sommer, Monika; Döhnel, Katrin; Zänkert, Sandra; Wüst, Stefan; Kudielka, Brigitte M

    2017-07-01

    In everyday life, moral decisions must frequently be made under acute stress. Although there is increasing evidence that both stress and cortisol affect moral judgment and behavior as well as decision-making in various domains unrelated to morality, surprisingly few attempts have been made to explore the effects of stress on everyday moral decision-making. Therefore, in the present study, we exposed 50 young healthy men to the Trier Social Stress Test (TSST) or its non-stressful placebo version (PTSST). We investigated the impact of acute stress exposure and stress-related cortisol levels on decision-making, decision certainty, and emotions in 28 everyday moral conflict situations with altruistic versus egoistic response alternatives. Results showed that the TSST-exposed group made more altruistic decisions than the non-stress control group, while groups did not differ in decision certainty and emotion ratings. Moreover, in correlational as well as regression analyses, additionally controlling for confounding variables, we observed significant positive associations between cortisol levels and altruistic decision-making. Further analyses revealed that altruistic decisions came along with significantly higher decision certainty and significantly more positive emotion ratings than egoistic decisions. Notably, our data also raise the idea that the personality trait agreeableness plays an important role in everyday moral decision-making. In sum, our findings provide initial evidence that both acute stress exposure and cortisol levels have prosocial effects on everyday moral decision-making in young healthy men. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Acute mental stress but not enforced muscle activity transiently increases natural cytotoxicity in spontaneously hypertensive rats.

    PubMed

    Jonsdottir, I H; Johansson, C; Asea, A; Hellstrand, K; Hoffmann, P

    1996-08-01

    The influence of acute mental stress and the effect of electrically induced skeletal muscle contractions on natural cytotoxicity in vivo was investigated in spontaneously hypertensive rats Natural cytotoxicity in vivo was measured as the clearance of injected 51Cr-labelled YAC-1 lymphoma cells from the lungs, which are specifically lysed by natural killer cells. The mental stress consisted of an air jet directed towards the animals in their cage for 25 min. During the mental stress there was a significant increase in natural cytotoxicity. Thus, retained radioactivity in the lungs was decreased to 74 +/- 6% of the control levels which was set to 100% (P < 0.01). This augmentation of YAC-1-cell clearance could be blocked with the beta-adrenergic receptor antagonist Timolol. Two hours after termination of the air stress, in vivo cytotoxicity had returned to control levels. In contrast, acute physical stress, consisting of electrically induced muscle contractions for 60 min, had no significant effects on in vivo cytotoxicity, either during the stimulation or 1, 2 or 24 h after the stimulation. Further, significantly increased plasma levels of adrenaline were seen after the air jet stress, but not after muscle stimulation. There were no significant changes in plasma noradrenaline levels either after air stress or muscle stimulation. These results indicate that changes in in vivo cytotoxicity after mild mental stress are dependent on increased plasma catecholamine levels while acute physical stress without changes in catecholamine levels, does not influence in vivo cytotoxicity.

  11. Dietary L-arginine supplement alleviates hepatic heat stress and improves feed conversion ratio of Pekin ducks exposed to high environmental temperature.

    PubMed

    Zhu, W; Jiang, W; Wu, L Y

    2014-12-01

    The current intensive indoor production system of commercial Pekin ducks never allows adequate water for swimming or wetting. Therefore, heat stress is a key factor affecting health and growth of ducks in the hot regions and season. Experiment 1 was conducted to study whether heat stress was deleterious to certain organs of ducks. Forty-one-day-old mixed-sex Pekin ducks were randomly allocated to four electrically heated battery brooders comprised of 10 ducks each. Ducks were suddenly exposed to 37 °C ambient temperature for 3 h and then slaughtered, in one brooder at 21 days and in another brooder at 49 days of age. The results showed that body weight and weight of immune organs, particularly liver markedly decreased in acute heat stress ducks compared with the control. Experiment 2 was carried out to investigate the influences of dietary L-arginine (Arg) supplement on weight and compositions of certain lymphoid organs, and growth performance in Pekin ducks, under daily cyclic hot temperature environment. A total of 151-day-old mixed-sex Pekin ducks were randomly divided into one negative control and two treatment groups, fed experimental diets supplemented with 0, 5, and 10 g L-Arginine (L-Arg)/kg to the basal diet respectively. Ducks were exposed to cyclic high temperature simulating natural summer season. The results showed that the addition of L-Arg improves feed conversion ratio (FCR) during a period of 7-week trial, as well as increases hepatic weight relative to body weight at 21 days, while decreases the hepatic water content at 49 days of age. This study indicated that the liver was more sensitive to acute heat stress, and the hepatic relative weight and chemical composition could be regulated by dietary L-Arg supplementation in Pekin ducks being reared at high ambient temperature. These beneficial effects of Arg on liver might be a cause of improved FCR. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

  12. Testosterone and acute stress are associated with fibrinogen and von Willebrand factor in African men: the SABPA study.

    PubMed

    Malan, Nicolaas T; von Känel, Roland; Schutte, Alta E; Huisman, Hugo W; Schutte, Rudolph; Smith, Wayne; Mels, Carina M; Kruger, Ruan; Meiring, Muriel; van Rooyen, Johannes M; Malan, Leoné

    2013-10-12

    Low testosterone, acute and chronic stress and hypercoagulation are all associated with hypertension and hypertension-related diseases. The interaction between these factors and future risk for coronary artery disease in Africans has not been fully elucidated. In this study, associations of testosterone, acute cardiovascular and coagulation stress responses with fibrinogen and von Willebrand factor in African and Caucasian men in a South African cohort were investigated. Cardiovascular variables were studied by means of beat-to-beat and ambulatory blood pressure monitoring. Fasting serum-, salivary testosterone and citrate coagulation markers were obtained from venous blood samples. Acute mental stress responses were evoked with the Stroop test. The African group demonstrated a higher cardiovascular risk compared to Caucasian men with elevated blood pressure, low-grade inflammation, chronic hyperglycemia (HbA1c), lower testosterone levels, and elevated von Willebrand factor (VWF) and fibrinogen levels. Blunted testosterone acute mental stress responses were demonstrated in African males. In multiple regression analyses, higher circulating levels of fibrinogen and VWF in Africans were associated with a low T environment (R(2) 0.24-0.28; p≤0.01), but only circulating fibrinogen in Caucasians. Regarding endothelial function, a low testosterone environment and a profile of augmented α-adrenergic acute mental stress responses (diastolic BP, D-dimer and testosterone) were associated with circulating VWF levels in Africans (Adj R(2) 0.24; p<0.05). An interdependence between acute mental stress, salivary testosterone, D-dimer and vascular responses existed in African males in their association with circulating VWF but no interdependence of the independent variables occurred with fibrinogen levels. © 2013.

  13. Negative Energy Balance Blocks Neural and Behavioral Responses to Acute Stress by "Silencing" Central Glucagon-Like Peptide 1 Signaling in Rats.

    PubMed

    Maniscalco, James W; Zheng, Huiyuan; Gordon, Patrick J; Rinaman, Linda

    2015-07-29

    Previous reports indicate that caloric restriction attenuates anxiety and other behavioral responses to acute stress, and blunts the ability of stress to increase anterior pituitary release of adrenocorticotropic hormone. Since hindbrain glucagon-like peptide-1 (GLP-1) neurons and noradrenergic prolactin-releasing peptide (PrRP) neurons participate in behavioral and endocrine stress responses, and are sensitive to the metabolic state, we examined whether overnight food deprivation blunts stress-induced recruitment of these neurons and their downstream hypothalamic and limbic forebrain targets. A single overnight fast reduced anxiety-like behavior assessed in the elevated-plus maze and acoustic startle test, including marked attenuation of light-enhanced startle. Acute stress [i.e., 30 min restraint (RES) or 5 min elevated platform exposure] robustly activated c-Fos in GLP-1 and PrRP neurons in fed rats, but not in fasted rats. Fasting also significantly blunted the ability of acute stress to activate c-Fos expression within the anterior ventrolateral bed nucleus of the stria terminalis (vlBST). Acute RES stress suppressed dark-onset food intake in rats that were fed ad libitum, whereas central infusion of a GLP-1 receptor antagonist blocked RES-induced hypophagia, and reduced the ability of RES to activate PrRP and anterior vlBST neurons in ad libitum-fed rats. Thus, an overnight fast "silences" GLP-1 and PrRP neurons, and reduces both anxiety-like and hypophagic responses to acute stress. The partial mimicking of these fasting-induced effects in ad libitum-fed rats after GLP-1 receptor antagonism suggests a potential mechanism by which short-term negative energy balance attenuates neuroendocrine and behavioral responses to acute stress. The results from this study reveal a potential central mechanism for the "metabolic tuning" of stress responsiveness. A single overnight fast, which markedly reduces anxiety-like behavior in rats, reduces or blocks the ability of

  14. The effect of acute physical and mental stress on soluble cellular adhesion molecule concentration.

    PubMed

    Crabb, E Blake; Franco, R Lee; Caslin, Heather L; Blanks, Anson M; Bowen, Mary K; Acevedo, Edmund O

    2016-07-15

    This study investigated the impact of acute physical and mental stress on serum concentrations of vascular cell adhesion molecule (VCAM)-1 and CX3CL1/fractalkine. Male volunteers (n=20; 21.3±0.55years of age) completed a graded treadmill test to exhaustion and a 20-minute mental stress task (Stroop Color-Word Test, mental arithmetic) on separate, non-consecutive days. Heart rate (HR) was measured at baseline and throughout exercise and mental stress. Blood was collected at baseline (PRE), immediately following (POST) and 30min after (POST30) exercise and mental stress. Soluble VCAM-1 and fractalkine were quantified in participant serum via enzyme-linked immunosorbent assays. Both treadmill exercise and the mental stress task significantly increased participant HR; although, exercise resulted in a substantially greater increase in participant HR compared to mental stress (197.82±11.99 vs. 38.67±3.10% [p<0.001]). VCAM-1 (815.74±139.55 vs. 738.67±131.59ng/mL [p=0.002]) and fractalkine (1.032±0.33 vs. 0.59±0.20ng/mL [p<0.001]) were significantly elevated in participant serum POST maximal exercise before returning to values similar to baseline at POST30. The acute mental stress task did not significantly alter serum VCAM-1 or fractalkine at any time point. In conclusion, maximal aerobic exercise results in a significant elevation of the soluble adhesion molecules VCAM-1 and fractalkine in the serum of adult males that does not occur following laboratory-induced mental stress. The findings of the current investigation may suggest a novel protective role for acute aerobic exercise in vascular health via exercise-induced CAM proteolysis. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. The multitasking framework: the effects of increasing workload on acute psychobiological stress reactivity.

    PubMed

    Wetherell, Mark A; Carter, Kirsty

    2014-04-01

    A variety of techniques exist for eliciting acute psychological stress in the laboratory; however, they vary in terms of their ease of use, reliability to elicit consistent responses and the extent to which they represent the stressors encountered in everyday life. There is, therefore, a need to develop simple laboratory techniques that reliably elicit psychobiological stress reactivity that are representative of the types of stressors encountered in everyday life. The multitasking framework is a performance-based, cognitively demanding stressor, representative of environments where individuals are required to attend and respond to several different stimuli simultaneously with varying levels of workload. Psychological (mood and perceived workload) and physiological (heart rate and blood pressure) stress reactivity was observed in response to a 15-min period of multitasking at different levels of workload intensity in a sample of 20 healthy participants. Multitasking stress elicited increases in heart rate and blood pressure, and increased workload intensity elicited dose-response increases in levels of perceived workload and mood. As individuals rarely attend to single tasks in real life, the multitasking framework provides an alternative technique for modelling acute stress and workload in the laboratory. Copyright © 2013 John Wiley & Sons, Ltd.

  16. Influence of acute exercise of varying intensity and duration on postprandial oxidative stress.

    PubMed

    Canale, Robert E; Farney, Tyler M; McCarthy, Cameron G; Bloomer, Richard J

    2014-09-01

    Aerobic exercise can reduce postprandial lipemia, and possibly oxidative stress, when performed prior to a lipid-rich meal. To compare the impact of acute exercise on postprandial oxidative stress. We compared aerobic and anaerobic exercise bouts of different intensities and durations on postprandial blood triglycerides (TAG), oxidative stress biomarkers (malondialdehyde, hydrogen peroxide, advanced oxidation protein products), and antioxidant status (trolox equivalent antioxidant capacity, superoxide dismutase, catalase, glutathione peroxidase). Twelve trained men (21-35 years) underwent four conditions: (1) No exercise rest; (2) 60-min aerobic exercise at 70% heart rate reserve; (3) five 60-s sprints at 100% max capacity; and (4) ten 15-s sprints at 200% max capacity. All exercise bouts were performed on a cycle ergometer. A high-fat meal was consumed 1 h after exercise cessation. Blood samples were collected pre-meal and 2 and 4 h post-meal and analyzed for TAG, oxidative stress biomarkers, and antioxidant status. No significant interaction or condition effects were noted for any variable (p > 0.05), with acute exercise having little to no effect on the magnitude of postprandial oxidative stress. In a sample of healthy, well-trained men, neither aerobic nor anaerobic exercise attenuates postprandial oxidative stress in response to a high-fat meal.

  17. Temperature Based Stress Analysis of Notched Members

    DTIC Science & Technology

    1979-03-01

    Strain Behavior 98 of Mild Steel 17 Percent Restoration vs. Residual Stress 99 18 Examples of a Good Weld and Three 100 Defective Welds vi LIST OF TABLES...measuring temperatures in deforming metals based on the use 27 of thermistor flakes. The system was used to show that more heating occurs near stress...thermocouples were welded to the specimen surface. This particular attachment method is quite suitable for stress analysis for the following reasons

  18. Cortisol modulates men's affiliative responses to acute social stress.

    PubMed

    Berger, Justus; Heinrichs, Markus; von Dawans, Bernadette; Way, Baldwin M; Chen, Frances S

    2016-01-01

    The dominant characterization of the physiological and behavioral human stress reaction is the fight-or-flight response. On the other hand, it has been suggested that social affiliation during stressful times ("tend-and-befriend") also represents a common adaptive response to stress, particularly for women. In the current study, we investigate the extent to which men may also show affiliative responses following acute stress. In addition, we examine a potential neuroendocrine modulator of the hypothesized affiliative response. Eighty male students (forty dyads) were recruited to undergo either the Trier Social Stress Test for Groups (TSST-G) or a non-stressful control situation. Subsequently, participants completed a dyadic interaction task and were then asked to report their feelings of psychological closeness to their interaction partner. Although participants assigned to the stress condition did not differ overall on psychological closeness from participants assigned to the control condition, participants with high cortisol responses to the stressor showed significantly higher ratings of psychological closeness to their interaction partner than participants with low cortisol responses. Our findings suggest that men may form closer temporary bonds following stressful situations that are accompanied by a significant cortisol response. We suggest that the traditional characterization of the male stress response in terms of "fight-or-flight" may be incomplete, and that social affiliation may in fact represent a common, adaptive response to stress in men. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Changes in protein expression in testes of L2 strain Taiwan country chickens in response to acute heat stress.

    PubMed

    Wang, Shih-Han; Cheng, Chuen-Yu; Chen, Chao-Jung; Chen, Hsin-Hsin; Tang, Pin-Chi; Chen, Chih-Feng; Lee, Yen-Pai; Huang, San-Yuan

    2014-07-01

    Heat stress causes a decrease of fertility in roosters. Yet, the way acute heat stress affects protein expression remains poorly understood. This study investigated differential protein expression in testes of the L2 strain of Taiwan country chickens following acute heat stress. Twelve 45-week-old roosters were allocated into four groups, including control roosters kept at 25 °C, roosters subjected to 38 °C acute heat stress for 4 hours without recovery, with 2 hours of recovery, and with 6 hours of recovery. Testis samples were collected for morphologic assay and protein analysis. Some of the differentially expressed proteins were validated by Western blot and immunohistochemistry. Abnormal and apoptotic spermatogenic cells were observed at 2 hours of recovery after acute heat stress, especially among the spermatocytes. Two-dimensional difference gel electrophoresis revealed that 119 protein spots were differentially expressed in chicken testes following heat stress, and peptide mass fingerprinting revealed that these spots contained 92 distinct proteins. In the heat-stressed samples, the heat shock proteins, chaperonin containing t-complex, and proteasome subunits were downregulated, and glutathione S-transferase, transgelin, and DJ-1 were upregulated. Our results demonstrate that acute heat stress impairs the processes of translation, protein folding, and protein degradation, and thus results in apoptosis and interferes with spermatogenesis. On the other hand, the increased expression of antioxidant enzymes, including glutathione S-transferase and DJ-1, may attenuate heat-induced damage. These findings may have implications for breeding chickens that can tolerate more extreme conditions. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Acute changes in foot strike pattern and cadence affect running parameters associated with tibial stress fractures.

    PubMed

    Yong, Jennifer R; Silder, Amy; Montgomery, Kate L; Fredericson, Michael; Delp, Scott L

    2018-05-18

    Tibial stress fractures are a common and debilitating injury that occur in distance runners. Runners may be able to decrease tibial stress fracture risk by adopting a running pattern that reduces biomechanical parameters associated with a history of tibial stress fracture. The purpose of this study was to test the hypothesis that converting to a forefoot striking pattern or increasing cadence without focusing on changing foot strike type would reduce injury risk parameters in recreational runners. Running kinematics, ground reaction forces and tibial accelerations were recorded from seventeen healthy, habitual rearfoot striking runners while running in their natural running pattern and after two acute retraining conditions: (1) converting to forefoot striking without focusing on cadence and (2) increasing cadence without focusing on foot strike. We found that converting to forefoot striking decreased two risk factors for tibial stress fracture: average and peak loading rates. Increasing cadence decreased one risk factor: peak hip adduction angle. Our results demonstrate that acute adaptation to forefoot striking reduces different injury risk parameters than acute adaptation to increased cadence and suggest that both modifications may reduce the risk of tibial stress fractures. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. The relationship of attachment insecurity to subjective stress and autonomic function during standardized acute stress in healthy adults.

    PubMed

    Maunder, Robert G; Lancee, William J; Nolan, Robert P; Hunter, Jonathan J; Tannenbaum, David W

    2006-03-01

    The purpose of this study was to test predicted relationships between adult attachment and stress using subjective and physiological measures. Sixty-seven healthy adults completed measures of adult attachment and perceived chronic stress. Subjective stress and the high-frequency (HF) and low-frequency (LF) spectral bandwidths of heart rate variability (HRV) were measured during a standardized stress protocol. Attachment anxiety is associated with between-subject differences in chronic perceived stress (P=.001) and subjective acute stress (P=.01). There is a main effect of attachment avoidance on between-subject differences in HF HRV (P=.004). Attachment avoidance is inversely associated with HF HRV, independent of age and variability in respiration. Attachment anxiety is associated with self-reported distress. Attachment avoidance is inversely associated with HF HRV, a marker of vagal influence on cardiac activity, but is not associated with subjective stress.

  2. Effect of paracetamol (acetaminophen) on body temperature in acute stroke: A meta-analysis.

    PubMed

    Fang, Junjie; Chen, Chensong; Cheng, Hongsen; Wang, Ren; Ma, Linhao

    2017-10-01

    The objective of this study was to assess the efficacy of paracetamol (acetaminophen) on body temperature in acute stroke. Medline, Cochrane Central Register of Controlled Trials, EMBASE, Chinese BioMedical Literature Database, China National Knowledge Infrastructure, and the World Health Organization (WHO) International Clinical Trials Registry Platform were searched electronically. Relevant journals and references of studies included were hand-searched for randomized controlled trials (RCT) and controlled clinical trials (CCT) regarding the efficacy of paracetamol (acetaminophen) on body temperature in acute stroke. Two reviewers independently performed data extraction and quality assessment. Data were analyzed using RevMan 5.3 software by the Cochrane Collaboration. Five studies were included. To compare the efficacy of paracetamol (acetaminophen) in acute stroke, the pooled RR (Risk Ratio) and its 95% CI of body temperature reduction at 24h from the start of treatment were -0.3 (95% CI: -0.52 to -0.08), with statistical significance (P=0.007). Consistently, the pooled RR (Risk Ratio) and its 95% CI of body temperature at 24h from the start of treatment were -0.22 (-0.29, -0.15), with statistical significance (P<0.00001). When analyzing the body temperature reduction after 5days from the start of treatment, the pooled RR (Risk Ratio) and its 95% CI were 0.04 (95% CI: -0.20 to 0.29), with no statistical significance (P=0.73). For functional outcome (mRS≤2) analysis, the pooled RR and its 95% CI were 1.08 (0.88, 1.32), with no statistical significance (P=0.45). In addition, the difference of serious adverse events between acetaminophen and placebo was 0.86 (95% CI: 0.62 to 1.2), with no statistical significance (P=0.27). Acetaminophen was revealed to have some favorable influence in body temperature reduction in acute stroke, but showed no important effect on improving functional outcome and reducing adverse events of patients. What is already known on this

  3. Social Media under the Skin: Facebook Use after Acute Stress Impairs Cortisol Recovery.

    PubMed

    Rus, Holly M; Tiemensma, Jitske

    2017-01-01

    Social media's influence on stress remains largely unknown. Conflicting research suggests that Facebook use may both enhance and undermine psychosocial constructs related to well-being. Using novel experimental methods, this study examined the impact of social media use on stress recovery. Facebook users ( n = 92, 49 males, mean age 19.55 SD = 1.63) were randomly assigned to use their own Facebook profile or quietly read after experiencing an acute social stressor. All participants showed significant changes in subjective and physiological stress markers during recovery. Participants who used Facebook experienced greater sustained cortisol concentration ( p < 0.05) when controlling for gender and emotional investment in the website compared to controls. Results suggest that social media use may delay or impair recovery after experiencing an acute social stressor. This novel study incorporated objective physiological markers with subjective psychosocial measures to show that Facebook use may negatively impact well-being.

  4. Social Media under the Skin: Facebook Use after Acute Stress Impairs Cortisol Recovery

    PubMed Central

    Rus, Holly M.; Tiemensma, Jitske

    2017-01-01

    Social media's influence on stress remains largely unknown. Conflicting research suggests that Facebook use may both enhance and undermine psychosocial constructs related to well-being. Using novel experimental methods, this study examined the impact of social media use on stress recovery. Facebook users (n = 92, 49 males, mean age 19.55 SD = 1.63) were randomly assigned to use their own Facebook profile or quietly read after experiencing an acute social stressor. All participants showed significant changes in subjective and physiological stress markers during recovery. Participants who used Facebook experienced greater sustained cortisol concentration (p < 0.05) when controlling for gender and emotional investment in the website compared to controls. Results suggest that social media use may delay or impair recovery after experiencing an acute social stressor. This novel study incorporated objective physiological markers with subjective psychosocial measures to show that Facebook use may negatively impact well-being. PMID:28974938

  5. Transcriptomic characterization of temperature stress responses in larval zebrafish.

    PubMed

    Long, Yong; Li, Linchun; Li, Qing; He, Xiaozhen; Cui, Zongbin

    2012-01-01

    Temperature influences nearly all biochemical, physiological and life history activities of fish, but the molecular mechanisms underlying the temperature acclimation remains largely unknown. Previous studies have identified many temperature-regulated genes in adult tissues; however, the transcriptional responses of fish larvae to temperature stress are not well understood. In this study, we characterized the transcriptional responses in larval zebrafish exposed to cold or heat stress using microarray analysis. In comparison with genes expressed in the control at 28 °C, a total of 2680 genes were found to be affected in 96 hpf larvae exposed to cold (16 °C) or heat (34 °C) for 2 and 48h and most of these genes were expressed in a temperature-specific and temporally regulated manner. Bioinformatic analysis identified multiple temperature-regulated biological processes and pathways. Biological processes overrepresented among the earliest genes induced by temperature stress include regulation of transcription, nucleosome assembly, chromatin organization and protein folding. However, processes such as RNA processing, cellular metal ion homeostasis and protein transport and were enriched in genes up-regulated under cold exposure for 48 h. Pathways such as mTOR signalling, p53 signalling and circadian rhythm were enriched among cold-induced genes, while adipocytokine signalling, protein export and arginine and praline metabolism were enriched among heat-induced genes. Although most of these biological processes and pathways were specifically regulated by cold or heat, common responses to both cold and heat stresses were also found. Thus, these findings provide new interesting clues for elucidation of mechanisms underlying the temperature acclimation in fish.

  6. Neurocognitive Function and State Cognitive Stress Appraisal Predict Cortisol Reactivity to an Acute Psychosocial Stressor in Adolescents

    PubMed Central

    Slattery, Marcia J.; Grieve, Adam J.; Ames, Michelle E.; Armstrong, Jeffrey M.; Essex, Marilyn J.

    2014-01-01

    Stress and associated alterations in hypothalamic-pituitary-adrenal (HPA) function have deleterious impacts on the development of multiple mental and physical health problems. Prior research has aimed to identify individuals most at risk for the development of these stress-related maladies by examining factors that may contribute to inter-individual differences in HPA responses to acute stress. The objectives of this study were to investigate, in adolescents, 1) whether differences in neurocognitive abilities influenced cortisol reactivity to an acute stressor, 2) whether internalizing psychiatric disorders influenced this relationship, and 3) whether acute cognitive stress-appraisal mechanisms mediated an association between neurocognitive function and cortisol reactivity. Subjects were 70 adolescents from a community sample who underwent standardized neurocognitive assessments of IQ, achievement, and declarative memory measures at mean age 14 and whose physiological and behavioral responses to a standardized psychosocial stress paradigm (Trier Social Stress Test, TSST) were assessed at mean age 18. Results showed that, among all adolescents, lower nonverbal memory performance predicted lower cortisol reactivity. In addition, internalizing disorders interacted with verbal memory such that the association with cortisol reactivity was strongest for adolescents with internalizing disorders. Finally, lower secondary cognitive appraisal of coping in anticipation of the TSST independently predicted lower cortisol reactivity but did not mediate the neurocognitive–cortisol relationship. Findings suggest that declarative memory may contribute to inter-individual differences in acute cortisol reactivity in adolescents, internalizing disorders may influence this relationship, and cognitive stress appraisal also predicts cortisol reactivity. Developmental, research, and clinical implications are discussed. PMID:23253895

  7. Deriving temperature and age appropriate heart rate centiles for children with acute infections.

    PubMed

    Thompson, M; Harnden, A; Perera, R; Mayon-White, R; Smith, L; McLeod, D; Mant, D

    2009-05-01

    To describe the reference range for heart rate in children aged 3 months-10 years presenting to primary care with self-limiting infections. Cross-sectional study of children presenting to primary care with suspected acute infection. Heart rate was measured using a pulse oximeter and axillary temperature using an electronic thermometer. Centile charts of heart rates expected at given temperatures for children with self-limiting infections were calculated. Ten general practice surgeries and two out-of-hours centres in England. 1933 children presenting with suspected acute infections were recruited from in-hours general practice surgeries (1050 or 54.3%) or out-of-hours centres (883 or 45.7%). After excluding children who subsequently attended hospital and those without a final diagnosis of acute infection, 1589 children were used to create the centile charts of whom (859 or 54.1%) had upper respiratory tract infections and (215 or 13.5%) non-specific viral illness. Median, 75th, 90th and 97th centiles of heart rate at each temperature level. Heart rate increased by 9.9-14.1 bpm with each 1 degrees C increment in temperature. The 50th, 75th, 90th and 97th centiles of heart rate at each temperature level are presented graphically. Age-specific centile charts of heart rates expected at different temperatures should be used by clinicians in the initial assessment of children with acute infections. The charts will identify children who have a heart rate higher than expected for a given temperature and facilitate the interpretation of changes in heart rate on reassessment. Further research on the predictive value of the centile charts is needed to optimise their diagnostic utility.

  8. Having your cake and eating it too: A habit of comfort food may link chronic social stress exposure and acute stress-induced cortisol hyporesponsiveness.

    USDA-ARS?s Scientific Manuscript database

    Stress has been tied to changes in eating behavior and food choice. Previous studies in rodents have shown that chronic stress increases palatable food intake which, in turn, increases mesenteric fat and inhibits acute stress-induced hypothalamic-pituitary-adrenal (HPA) axis activity. The effect of...

  9. Weight loss in rats exposed to repeated acute restraint stress is independent of energy or leptin status.

    PubMed

    Harris, Ruth B S; Mitchell, Tiffany D; Simpson, Jacob; Redmann, Stephen M; Youngblood, Bradley D; Ryan, Donna H

    2002-01-01

    Acute release of corticotropin-releasing factor (CRF) during repeated restraint (3-h restraint on each of 3 days) causes temporary hypophagia but chronic suppression of body weight in rats. Here we demonstrated that a second bout of repeated restraint caused additional weight loss, but continuing restraint daily for 10 days did not increase weight loss because the rats adapted to the stress. In these two studies serum leptin, which suppresses the endocrine response to stress, was reduced in restrained rats. Peripheral infusion of leptin before and during restraint did not prevent stress-induced weight loss, although stress-induced corticosterone release was suppressed. Restrained rats were hyperthermic during restraint, but there was no evidence that fever or elevated free interleukin-6 caused the sustained reduction in weight. Restraining food-restricted rats caused a small but significant weight loss. Food-restricted rats fed ad libitum after the end of restraint showed a blunted hyperphagia and slower rate of weight regain than their controls. These results indicate that repeated acute stress induces a chronic change in weight independent of stress-induced hypophagia and may represent a change in homeostasis initiated by repeated acute activation of the central CRF system.

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

    PubMed

    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.

  11. Hemolymph microbiome of Pacific oysters in response to temperature, temperature stress and infection

    PubMed Central

    Lokmer, Ana; Mathias Wegner, Karl

    2015-01-01

    Microbiota provide their hosts with a range of beneficial services, including defense from external pathogens. However, host-associated microbial communities themselves can act as a source of opportunistic pathogens depending on the environment. Marine poikilotherms and their microbiota are strongly influenced by temperature, but experimental studies exploring how temperature affects the interactions between both parties are rare. To assess the effects of temperature, temperature stress and infection on diversity, composition and dynamics of the hemolymph microbiota of Pacific oysters (Crassostrea gigas), we conducted an experiment in a fully-crossed, three-factorial design, in which the temperature acclimated oysters (8 or 22 °C) were exposed to temperature stress and to experimental challenge with a virulent Vibrio sp. strain. We monitored oyster survival and repeatedly collected hemolymph of dead and alive animals to determine the microbiome composition by 16s rRNA gene amplicon pyrosequencing. We found that the microbial dynamics and composition of communities in healthy animals (including infection survivors) were significantly affected by temperature and temperature stress, but not by infection. The response was mediated by changes in the incidence and abundance of operational taxonomic units (OTUs) and accompanied by little change at higher taxonomic levels, indicating dynamic stability of the hemolymph microbiome. Dead and moribund oysters, on the contrary, displayed signs of community structure disruption, characterized by very low diversity and proliferation of few OTUs. We can therefore link short-term responses of host-associated microbial communities to abiotic and biotic factors and assess the potential feedback between microbiota dynamics and host survival during disease. PMID:25180968

  12. Acute Stress Dysregulates the LPP ERP Response to Emotional Pictures and Impairs Sustained Attention: Time-Sensitive Effects

    PubMed Central

    Alomari, Rima A.; Fernandez, Mercedes; Banks, Jonathan B.; Acosta, Juliana; Tartar, Jaime L.

    2015-01-01

    Stress can increase emotional vigilance at the cost of a decrease in attention towards non-emotional stimuli. However, the time-dependent effects of acute stress on emotion processing are uncertain. We tested the effects of acute stress on subsequent emotion processing up to 40 min following an acute stressor. Our measure of emotion processing was the late positive potential (LPP) component of the visual event-related potential (ERP), and our measure of non-emotional attention was the sustained attention to response task (SART). We also measured cortisol levels before and after the socially evaluated cold pressor test (SECPT) induction. We found that the effects of stress on the LPP ERP emotion measure were time sensitive. Specifically, the LPP ERP was only altered in the late time-point (30–40 min post-stress) when cortisol was at its highest level. Here, the LPP no longer discriminated between the emotional and non-emotional picture categories, most likely because neutral pictures were perceived as emotional. Moreover, compared to the non-stress condition, the stress-condition showed impaired performance on the SART. Our results support the idea that a limit in attention resources after an emotional stressor is associated with the brain incorrectly processing non-emotional stimuli as emotional and interferes with sustained attention. PMID:26010485

  13. Acute Stress Dysregulates the LPP ERP Response to Emotional Pictures and Impairs Sustained Attention: Time-Sensitive Effects.

    PubMed

    Alomari, Rima A; Fernandez, Mercedes; Banks, Jonathan B; Acosta, Juliana; Tartar, Jaime L

    2015-05-20

    Stress can increase emotional vigilance at the cost of a decrease in attention towards non-emotional stimuli. However, the time-dependent effects of acute stress on emotion processing are uncertain. We tested the effects of acute stress on subsequent emotion processing up to 40 min following an acute stressor. Our measure of emotion processing was the late positive potential (LPP) component of the visual event-related potential (ERP), and our measure of non-emotional attention was the sustained attention to response task (SART). We also measured cortisol levels before and after the socially evaluated cold pressor test (SECPT) induction. We found that the effects of stress on the LPP ERP emotion measure were time sensitive. Specifically, the LPP ERP was only altered in the late time-point (30-40 min post-stress) when cortisol was at its highest level. Here, the LPP no longer discriminated between the emotional and non-emotional picture categories, most likely because neutral pictures were perceived as emotional. Moreover, compared to the non-stress condition, the stress-condition showed impaired performance on the SART. Our results support the idea that a limit in attention resources after an emotional stressor is associated with the brain incorrectly processing non-emotional stimuli as emotional and interferes with sustained attention.

  14. Effect of Acute Psychological Stress on Prefrontal GABA Concentration Determined by Proton Magnetic Resonance Spectroscopy

    PubMed Central

    Hasler, Gregor; van der Veen, Jan Willem; Grillon, Christian; Drevets, Wayne C.; Shen, Jun

    2011-01-01

    Objective Impaired function of the central gamma-aminobutyric acid (GABA) system, which provides the brain’s major inhibitory pathways, is thought to play an important role in the pathophysiology of anxiety disorders. The effect of acute psychological stress on the human GABA-ergic system is still unknown, however. The purpose of this study was to determine the effect of acute stress on prefrontal GABA levels. Method A recently developed noninvasive magnetic resonance spectroscopy method was used to measure changes in the GABA concentration of the prefrontal cortex in 10 healthy human subjects during a threat-of-shock condition and during a safe condition (two sessions on different days). The main outcome measure was the mean GABA concentration within a 3×3×2-cm3 voxel selected from the medial prefrontal cortex. Results Prefrontal GABA decreased by approximately 18% in the threat-of-shock condition relative to the safe condition. This reduction was specific to GABA, since the concentrations of N-acetyl-aspartate, choline-containing compounds, and glutamate/glutamine levels obtained in the same spectra did not change significantly. Conclusions This result appeared compatible with evidence from preclinical studies in rodents, which showed rapid presynaptic down-regulation of GABA-ergic neurotransmission in response to acute psychological stress. The molecular mechanism and functional significance of this reduced inhibitory effect of acute psychological stress in relation to impaired GABA-ergic function in anxiety disorders merit further investigation. PMID:20634372

  15. Progenitor cells are mobilized by acute psychological stress but not beta-adrenergic receptor agonist infusion.

    PubMed

    Riddell, Natalie E; Burns, Victoria E; Wallace, Graham R; Edwards, Kate M; Drayson, Mark; Redwine, Laura S; Hong, Suzi; Bui, Jack C; Fischer, Johannes C; Mills, Paul J; Bosch, Jos A

    2015-10-01

    Stimuli that activate the sympathetic nervous system, such as acute psychological stress, rapidly invoke a robust mobilization of lymphocytes into the circulation. Experimental animal studies suggest that bone marrow-derived progenitor cells (PCs) also mobilize in response to sympathetic stimulation. Here we tested the effects of acute psychological stress and brief pharmacological β-adrenergic (βAR) stimulation on peripheral PC numbers in humans. In two studies, we investigated PC mobilization in response to an acute speech task (n=26) and βAR-agonist (isoproterenol) infusion (n=20). A subset of 8 participants also underwent the infusion protocol with concomitant administration of the βAR-antagonist propranolol. Flow cytometry was used to enumerate lymphocyte subsets, total progenitor cells, total haematopoietic stem cells (HSC), early HSC (multi-lineage potential), late HSC (lineage committed), and endothelial PCs (EPCs). Both psychological stress and βAR-agonist infusion caused the expected mobilization of total monocytes and lymphocytes and CD8(+) T lymphocytes. Psychological stress also induced a modest, but significant, increase in total PCs, HSCs, and EPC numbers in peripheral blood. However, infusion of a βAR-agonist did not result in a significant change in circulating PCs. PCs are rapidly mobilized by psychological stress via mechanisms independent of βAR-stimulation, although the findings do not exclude βAR-stimulation as a possible cofactor. Considering the clinical and physiological relevance, further research into the mechanisms involved in stress-induced PC mobilization seems warranted. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Progenitor cells are mobilized by acute psychological stress but not beta-adrenergic receptor agonist infusion

    PubMed Central

    Riddell, Natalie E.; Burns, Victoria E.; Wallace, Graham R.; Edwards, Kate M.; Drayson, Mark; Redwine, Laura S.; Hong, Suzi; Bui, Jack D.; Fischer, Johannes C.; Mills, Paul J.; Bosch, Jos A.

    2015-01-01

    Objectives Stimuli that activate the sympathetic nervous system, such as acute psychological stress, rapidly invoke a robust mobilization of lymphocytes into the circulation. Experimental animal studies suggest that bone marrow-derived progenitor cells (PCs) also mobilize in response to sympathetic stimulation. Here we tested the effects of acute psychological stress and brief pharmacological β-adrenergic (βAR) stimulation on peripheral PC numbers in humans. Methods In two studies, we investigated PC mobilization in response to an acute speech task (n=26) and βAR-agonist (isoproterenol) infusion (n=20). A subset of 8 participants also underwent the infusion protocol with concomitant administration of the βAR-antagonist propranolol. Flow cytometry was used to enumerate lymphocyte subsets, total progenitor cells, total haematopoietic stem cells (HSC), early HSC (multi-lineage potential), late HSC (lineage committed), and endothelial PCs (EPCs). Results Both psychological stress and βAR-agonist infusion caused the expected mobilization of total monocytes and lymphocytes and CD8+ T lymphocytes. Psychological stress also induced a modest, but significant, increase in total PCs, HSCs, and EPC numbers in peripheral blood. However, infusion of a βAR-agonist did not result in a significant change in circulating PCs. Conclusion PCs are rapidly mobilized by psychological stress via mechanisms independent of βAR-stimulation, although the findings do not exclude βAR-stimulation as a possible cofactor. Considering the clinical and physiological relevance, further research into the mechanisms involved in stress-induced PC mobilization seems warranted. PMID:25747743

  17. The impact of temperature stress and pesticide exposure on mortality and disease susceptibility of endangered Pacific salmon.

    PubMed

    Dietrich, Joseph P; Van Gaest, Ahna L; Strickland, Stacy A; Arkoosh, Mary R

    2014-08-01

    Anthropogenic stressors, including chemical contamination and temperature stress, may contribute to increased disease susceptibility in aquatic animals. Specifically, the organophosphate pesticide malathion has been detected in surface waters inhabited by threatened and endangered salmon. In the presence of increasing water temperatures, malathion may increase susceptibility to disease and ultimately threaten salmon survival. This work examines the effect of acute and sublethal exposures to malathion on ocean-type subyearling Chinook salmon held under two temperature regimes. Chinook salmon were exposed to malathion at optimal (11 °C) or elevated (19 and 20 °C) temperatures. The influence of temperature on the acute toxicity of malathion was determined by generating 96-h lethal concentration (LC) curves. A disease challenge assay was also used to assess the effects of sublethal malathion exposure. The malathion concentration that resulted in 50% mortality (LC50; 274.1 μg L(-1)) of the Chinook salmon at 19 °C was significantly less than the LC50 at 11 °C (364.2 μg L(-1)). Mortality increased 11.2% in Chinook salmon exposed to malathion at the elevated temperature and challenged with Aeromonas salmonicida compared to fish held at the optimal temperature and exposed to malathion or the carrier control. No difference in disease challenge mortality was observed among malathion-exposed and unexposed fish at the optimal temperature. The interaction of co-occurring stressors may have a greater impact on salmon than if they occur in isolation. Ecological risk assessments considering the effects of an individual stressor on threatened and endangered salmon may underestimate risk when additional stressors are present in the environment. Published by Elsevier Ltd.

  18. Nickel-titanium alloys: stress-related temperature transitional range.

    PubMed

    Santoro, M; Beshers, D N

    2000-12-01

    The inducement of mechanical stress within nickel-titanium wires can influence the transitional temperature range of the alloy and therefore the expression of the superelastic properties. An analogous variation of the transitional temperature range may be expected during orthodontic therapy, when the archwires are engaged into the brackets. To investigate this possibility, samples of currently used orthodontic nickel-titanium wires (Sentalloy, GAC; Copper Ni-Ti superelastic at 27 degrees C, 35 degrees C, 40 degrees C, Ormco; Nitinol Heat-Activated, 3M-Unitek) were subjected to temperature cycles ranging between 4 degrees C and 60 degrees C. The wires were mounted in a plexiglass loading device designed to simulate clinical situations of minimum and severe dental crowding. Electrical resistivity was used to monitor the phase transformations. The data were analyzed with paired t tests. The results confirmed the presence of displacements of the transitional temperature ranges toward higher temperatures when stress was induced. Because nickel-titanium wires are most commonly used during the aligning stage in cases of severe dental crowding, particular attention was given to the performance of the orthodontic wires under maximum loading. An alloy with a stress-related transitional temperature range corresponding to the fluctuations of the oral temperature should express superelastic properties more consistently than others. According to our results, Copper Ni-Ti 27 degrees C and Nitinol Heat-Activated wires may be considered suitable alloys for the alignment stage.

  19. Fear extinction deficits following acute stress associate with increased spine density and dendritic retraction in basolateral amygdala neurons

    PubMed Central

    Maroun, Mouna; Ioannides, Pericles J.; Bergman, Krista L.; Kavushansky, Alexandra; Holmes, Andrew; Wellman, Cara L.

    2013-01-01

    Stress-sensitive psychopathologies such as post-traumatic stress disorder are characterized by deficits in fear extinction and dysfunction of corticolimbic circuits mediating extinction. Chronic stress facilitates fear conditioning, impairs extinction, and produces dendritic proliferation in the basolateral amygdala (BLA), a critical site of plasticity for extinction. Acute stress impairs extinction, alters plasticity in the medial prefrontal cortex-to-BLA circuit, and causes dendritic retraction in the medial prefrontal cortex. Here, we examined extinction learning and basolateral amygdala pyramidal neuron morphology in adult male rats following a single elevated platform stress. Acute stress impaired extinction acquisition and memory, and produced dendritic retraction and increased mushroom spine density in basolateral amygdala neurons in the right hemisphere. Unexpectedly, irrespective of stress, rats that underwent fear and extinction testing showed basolateral amygdala dendritic retraction and altered spine density relative to non-conditioned rats, particularly in the left hemisphere. Thus, extinction deficits produced by acute stress are associated with increased spine density and dendritic retraction in basolateral amygdala pyramidal neurons. Furthermore, the finding that conditioning and extinction as such was sufficient to alter basolateral amygdala morphology and spine density illustrates the sensitivity of basolateral amygdala morphology to behavioral manipulation. These findings may have implications for elucidating the role of the amygdala in the pathophysiology of stress-related disorders. PMID:23714419

  20. Statistical damage constitutive model for rocks subjected to cyclic stress and cyclic temperature

    NASA Astrophysics Data System (ADS)

    Zhou, Shu-Wei; Xia, Cai-Chu; Zhao, Hai-Bin; Mei, Song-Hua; Zhou, Yu

    2017-10-01

    A constitutive model of rocks subjected to cyclic stress-temperature was proposed. Based on statistical damage theory, the damage constitutive model with Weibull distribution was extended. Influence of model parameters on the stress-strain curve for rock reloading after stress-temperature cycling was then discussed. The proposed model was initially validated by rock tests for cyclic stress-temperature and only cyclic stress. Finally, the total damage evolution induced by stress-temperature cycling and reloading after cycling was explored and discussed. The proposed constitutive model is reasonable and applicable, describing well the stress-strain relationship during stress-temperature cycles and providing a good fit to the test results. Elastic modulus in the reference state and the damage induced by cycling affect the shape of reloading stress-strain curve. Total damage induced by cycling and reloading after cycling exhibits three stages: initial slow increase, mid-term accelerated increase, and final slow increase.

  1. The effect of mild acute stress during memory consolidation on emotional recognition memory.

    PubMed

    Corbett, Brittany; Weinberg, Lisa; Duarte, Audrey

    2017-11-01

    Stress during consolidation improves recognition memory performance. Generally, this memory benefit is greater for emotionally arousing stimuli than neutral stimuli. The strength of the stressor also plays a role in memory performance, with memory performance improving up to a moderate level of stress and thereafter worsening. As our daily stressors are generally minimal in strength, we chose to induce mild acute stress to determine its effect on memory performance. In the current study, we investigated if mild acute stress during consolidation improves memory performance for emotionally arousing images. To investigate this, we had participants encode highly arousing negative, minimally arousing negative, and neutral images. We induced stress using the Montreal Imaging Stress Task (MIST) in half of the participants and a control task to the other half of the participants directly after encoding (i.e. during consolidation) and tested recognition 48h later. We found no difference in memory performance between the stress and control group. We found a graded pattern among confidence, with responders in the stress group having the least amount of confidence in their hits and controls having the most. Across groups, we found highly arousing negative images were better remembered than minimally arousing negative or neutral images. Although stress did not affect memory accuracy, responders, as defined by cortisol reactivity, were less confident in their decisions. Our results suggest that the daily stressors humans experience, regardless of their emotional affect, do not have adverse effects on memory. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. High temperature aqueous stress corrosion testing device

    DOEpatents

    Bornstein, A.N.; Indig, M.E.

    1975-12-01

    A description is given of a device for stressing tensile samples contained within a high temperature, high pressure aqueous environment, thereby permitting determination of stress corrosion susceptibility of materials in a simple way. The stressing device couples an external piston to an internal tensile sample via a pull rod, with stresses being applied to the sample by pressurizing the piston. The device contains a fitting/seal arrangement including Teflon and weld seals which allow sealing of the internal system pressure and the external piston pressure. The fitting/seal arrangement allows free movement of the pull rod and the piston.

  3. Neural Mechanisms Underlying 5-HTTLPR Related Sensitivity to Acute Stress

    PubMed Central

    Drabant, Emily M; Ramel, Wiveka; Edge, Michael D; Hyde, Luke W; Kuo, Janice R; Goldin, Philippe R; Hariri, Ahmad R; Gross, James J

    2013-01-01

    Objective Many studies have shown that 5-HTTLPR genotype interacts with exposure to stress in conferring risk for psychopathology. However, the specific neural mechanisms through which this gene-by-environment interaction confers risk remain largely unknown, and no study to date has directly examined the modulatory effects of the 5-HTTLPR on corticolimbic circuit responses during exposure to acute stress. Methods An acute laboratory stressor was administered to 51 healthy women during BOLD fMRI scanning. In this task, electric shocks of uncertain intensity were threatened and unpredictably delivered to the wrist after a long anticipatory cue period of unpredictable duration. Results Relative to those carrying the L allele, SS homozygotes showed enhanced activation during threat anticipation in a network of regions including amygdala, hippocampus, anterior insula, thalamus, pulvinar, caudate, precuneus, anterior cingulate cortex, and medial prefrontal cortex. SS homozygotes also displayed enhanced positive coupling between medial prefrontal cortex activation and anxiety experience, whereas individuals carrying the L allele displayed enhanced negative coupling between insula activation and perceived success at regulating anxiety. Conclusions The present findings suggest that, when exposed to stress, SS homozygotes may preferentially engage neural systems which enhance fear and arousal, modulate attention toward threat, and perseverate on emotional salience of the threat. This may be one mechanism underlying risk for psychopathology conferred by the S allele upon exposure to life stressors. PMID:22362395

  4. Ceramic Composite Intermediate Temperature Stress-Rupture Properties Improved Significantly

    NASA Technical Reports Server (NTRS)

    Morscher, Gregory N.; Hurst, Janet B.

    2002-01-01

    Silicon carbide (SiC) composites are considered to be potential materials for future aircraft engine parts such as combustor liners. It is envisioned that on the hot side (inner surface) of the combustor liner, composites will have to withstand temperatures in excess of 1200 C for thousands of hours in oxidizing environments. This is a severe condition; however, an equally severe, if not more detrimental, condition exists on the cold side (outer surface) of the combustor liner. Here, the temperatures are expected to be on the order of 800 to 1000 C under high tensile stress because of thermal gradients and attachment of the combustor liner to the engine frame (the hot side will be under compressive stress, a less severe stress-state for ceramics). Since these composites are not oxides, they oxidize. The worst form of oxidation for strength reduction occurs at these intermediate temperatures, where the boron nitride (BN) interphase oxidizes first, which causes the formation of a glass layer that strongly bonds the fibers to the matrix. When the fibers strongly bond to the matrix or to one another, the composite loses toughness and strength and becomes brittle. To increase the intermediate temperature stress-rupture properties, researchers must modify the BN interphase. With the support of the Ultra-Efficient Engine Technology (UEET) Program, significant improvements were made as state-of-the-art SiC/SiC composites were developed during the Enabling Propulsion Materials (EPM) program. Three approaches were found to improve the intermediate-temperature stress-rupture properties: fiber-spreading, high-temperature silicon- (Si) doped boron nitride (BN), and outside-debonding BN.

  5. KCNQ/Kv7 channel activator flupirtine protects against acute stress-induced impairments of spatial memory retrieval and hippocampal LTP in rats.

    PubMed

    Li, C; Huang, P; Lu, Q; Zhou, M; Guo, L; Xu, X

    2014-11-07

    Spatial memory retrieval and hippocampal long-term potentiation (LTP) are impaired by stress. KCNQ/Kv7 channels are closely associated with memory and the KCNQ/Kv7 channel activator flupirtine represents neuroprotective effects. This study aims to test whether KCNQ/Kv7 channel activation prevents acute stress-induced impairments of spatial memory retrieval and hippocampal LTP. Rats were placed on an elevated platform in the middle of a bright room for 30 min to evoke acute stress. The expression of KCNQ/Kv7 subunits was analyzed at 1, 3 and 12 h after stress by Western blotting. Spatial memory was examined by the Morris water maze (MWM) and the field excitatory postsynaptic potential (fEPSP) in the hippocampal CA1 area was recorded in vivo. Acute stress transiently decreased the expression of KCNQ2 and KCNQ3 in the hippocampus. Acute stress impaired the spatial memory retrieval and hippocampal LTP, the KCNQ/Kv7 channel activator flupirtine prevented the impairments, and the protective effects of flupirtine were blocked by XE-991 (10,10-bis(4-Pyridinylmethyl)-9(10H)-anthracenone), a selective KCNQ channel blocker. Furthermore, acute stress decreased the phosphorylation of glycogen synthase kinase-3β (GSK-3β) at Ser9 in the hippocampus, and flupirtine inhibited the reduction. These results suggest that the KCNQ/Kv7 channels may be a potential target for protecting both hippocampal synaptic plasticity and spatial memory retrieval from acute stress influences. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  6. Acclimation to cold and warm temperatures is associated with differential expression of male carp blood proteins involved in acute phase and stress responses, and lipid metabolism.

    PubMed

    Dietrich, Mariola A; Hliwa, Piotr; Adamek, Mikołaj; Steinhagen, Dieter; Karol, Halina; Ciereszko, Andrzej

    2018-05-01

    The environmental temperature affects plasma biochemical indicators, antioxidant status and hematological and immunological parameters in fish. So far, only single blood proteins have been identified in response to temperature changes. The aim of this study was to compare the proteome of carp blood plasma from males acclimated to warm (30 °C) and cold (10 °C) temperatures by two-dimensional differential gel electrophoresis followed by MALDI-TOF/TOF mass spectrometry. A total of 47 spots were found to be differentially regulated by temperature (>1.2-fold change, p < 0.05): 25 protein spots were more abundant in warm-acclimated males and 22 were enriched in cold-acclimated males. The majority of differentially regulated proteins were associated with acute phase response signalling involved in: i) activation of the complement system (complement C3-H1), ii) neutralization of proteolytic enzymes (inter-alpha inhibitor H3, fetuin, serpinA1, antithrombin, alpha2-macroglobulin), iii) scavenging of free hemoglobin and radicals (haptoglobin, Wap65 kDa), iv) clot-formation (fibrinogen beta and alpha chain, T-kininogen) and v) the host's immune response modulation (ApoA1 and ApoA2). However, quite different sets of these proteins or proteoforms were involved in response to cold and warm temperatures. In addition, cold acclimation seems to be related to the proteins involved in lipid metabolism (apolipoproteins A and 14 kDa) and stress response (corticosteroid binding globulin). We discovered a strongly regulated protein Cap31 upon cold acclimation, which can serve as a potential blood biomarker of cold response in carp. These studies significantly extend our knowledge concerning mechanisms underlying thermal adaptation in poikilotherms. Copyright © 2018. Published by Elsevier Ltd.

  7. Ambient temperature and volume of perihematomal edema in acute intracerebral haemorrhage: the INTERACT1 study.

    PubMed

    Zheng, Danni; Arima, Hisatomi; Heeley, Emma; Karpin, Anne; Yang, Jie; Chalmers, John; Anderson, Craig S

    2015-01-01

    As no human data exist, we aimed to determine the relation between ambient temperature and volume of perihematomal 'cerebral' edema in acute spontaneous intracerebral haemorrhage (ICH) among Chinese participants of the pilot phase, Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage Trial (INTERACT1). INTERACT1 was a multicenter, open, blind outcome assessed, randomized controlled trial of intensive (systolic target <140 mmHg) vs. guideline-recommended (systolic target <180 mmHg) blood pressure (BP) lowering in 404 patients with acute ICH. Data on ambient temperature (mean, minimum, maximum, and range) on the day of each participant's ICH obtained from China Meteorological Data Sharing Service System were linked to other data including edema volumes. Multivariable regression analyses were performed to evaluate association between ambient temperature and edema volumes. A generalized linear regression model with a generalized estimating equations approach (GEE) was used to assess any association of ambient temperature and change in edema volume over 72 h. A total of 250 of all 384 Chinese participants had complete data that showed positive associations between ambient temperature (mean and minimum temperatures) and edema volumes at each time point over 72 h after hospital admission (all P < 0·05). All temperature parameters except diurnal temperature range were positively associated with edema volume after adjustment for confounding variables (all P < 0·02). An apparent positive association exists between ambient temperature and perihematomal edema volume in acute spontaneous ICH. © 2014 World Stroke Organization.

  8. An approach to an acute emotional stress reference scale.

    PubMed

    Garzon-Rey, J M; Arza, A; de-la-Camara, C; Lobo, A; Armario, A; Aguilo, J

    2017-06-16

    The clinical diagnosis aims to identify the degree of affectation of the psycho-physical state of the patient as a guide to therapeutic intervention. In stress, the lack of a measurement tool based on a reference makes it difficult to quantitatively assess this degree of affectation. To define and perform a primary assessment of a standard reference in order to measure acute emotional stress from the markers identified as indicators of the degree. Psychometric tests and biochemical variables are, in general, the most accepted stress measurements by the scientific community. Each one of them probably responds to different and complementary processes related to the reaction to a stress stimulus. The reference that is proposed is a weighted mean of these indicators by assigning them relative weights in accordance with a principal components analysis. An experimental study was conducted on 40 healthy young people subjected to the psychosocial stress stimulus of the Trier Social Stress Test in order to perform a primary assessment and consistency check of the proposed reference. The proposed scale clearly differentiates between the induced relax and stress states. Accepting the subjectivity of the definition and the lack of a subsequent validation with new experimental data, the proposed standard differentiates between a relax state and an emotional stress state triggered by a moderate stress stimulus, as it is the Trier Social Stress Test. The scale is robust. Although the variations in the percentage composition slightly affect the score, but they do not affect the valid differentiation between states.

  9. Negative Energy Balance Blocks Neural and Behavioral Responses to Acute Stress by “Silencing” Central Glucagon-Like Peptide 1 Signaling in Rats

    PubMed Central

    Maniscalco, James W.; Zheng, Huiyuan; Gordon, Patrick J.

    2015-01-01

    Previous reports indicate that caloric restriction attenuates anxiety and other behavioral responses to acute stress, and blunts the ability of stress to increase anterior pituitary release of adrenocorticotropic hormone. Since hindbrain glucagon-like peptide-1 (GLP-1) neurons and noradrenergic prolactin-releasing peptide (PrRP) neurons participate in behavioral and endocrine stress responses, and are sensitive to the metabolic state, we examined whether overnight food deprivation blunts stress-induced recruitment of these neurons and their downstream hypothalamic and limbic forebrain targets. A single overnight fast reduced anxiety-like behavior assessed in the elevated-plus maze and acoustic startle test, including marked attenuation of light-enhanced startle. Acute stress [i.e., 30 min restraint (RES) or 5 min elevated platform exposure] robustly activated c-Fos in GLP-1 and PrRP neurons in fed rats, but not in fasted rats. Fasting also significantly blunted the ability of acute stress to activate c-Fos expression within the anterior ventrolateral bed nucleus of the stria terminalis (vlBST). Acute RES stress suppressed dark-onset food intake in rats that were fed ad libitum, whereas central infusion of a GLP-1 receptor antagonist blocked RES-induced hypophagia, and reduced the ability of RES to activate PrRP and anterior vlBST neurons in ad libitum-fed rats. Thus, an overnight fast “silences” GLP-1 and PrRP neurons, and reduces both anxiety-like and hypophagic responses to acute stress. The partial mimicking of these fasting-induced effects in ad libitum-fed rats after GLP-1 receptor antagonism suggests a potential mechanism by which short-term negative energy balance attenuates neuroendocrine and behavioral responses to acute stress. SIGNIFICANCE STATEMENT The results from this study reveal a potential central mechanism for the “metabolic tuning” of stress responsiveness. A single overnight fast, which markedly reduces anxiety-like behavior in rats

  10. Stress hormonal changes in the brain and plasma after acute noise exposure in mice.

    PubMed

    Jin, Sang Gyun; Kim, Min Jung; Park, So Young; Park, Shi Nae

    2017-06-01

    To investigate the effects of acute noise stress on two amine stress hormones, norepinephrine (NE) and 5-hydroxyindoleacetic acid (5-HIAA) in the brain and plasma of mice after noise exposure. Mice were grouped into the control and noise groups. Mice in the noise group were exposed to white noise of 110dB sound pressure level for 60min. Auditory brainstem response thresholds, distortion product otoacoustic emissions, the organ of Corti grading scores, western blots of NE/5-HIAA in the whole brain and hippocampus, and the plasma levels of NE/5-HIAA were compared between the two groups. Significant hearing loss and cochlear damage were demonstrated in the noise group. NE and 5-HIAA in the hippocampus were elevated in the noise group (p=0.019/0.022 for NE/5-HIAA vs. the control). Plasma levels of NE and 5-HIAA were not statistically different between the groups (p=0.052/0.671 for NE/5-HIAA). Hearing loss with outer hair cell dysfunction and morphological changes of the organ of Corti after noise exposure in C57BL/6 mice proved the reliability of our animal model as an acute noise stress model. NE and 5-HIAA are suggested to be the potential biomarkers for acute noise stress in the hippocampus. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Retigabine ameliorates acute stress-induced impairment of spatial memory retrieval through regulating USP2 signaling pathways in hippocampal CA1 area.

    PubMed

    Li, Cai; Zhang, Ji; Xu, Haiwei; Chang, Mujun; Lv, Chuntao; Xue, Wenhua; Song, Zhizhen; Zhang, Lizhen; Zhang, Xiaojian; Tian, Xin

    2018-06-01

    Acute stress could trigger maladaptive changes associated with stress-related cognitive and emotional deficits. Dysfunction of ion channel or receptor in the hippocampal area has been linked to the cognitive deficits induced by stress. It is known that Kv7 channel openers, including FDA-approved drug retigabine, show cognitive protective efficacy. However, the underlying molecular mechanisms remain elusive. Here we showed that exposing adult male rats to acute stress significantly impaired the spatial memory, a cognitive process controlled by the hippocampus. Concomitantly, significantly reduced AMPA receptor expression was found in hippocampal CA1 area from acute stressed rats. This effect relied on the down-regulation of deubiquitinating enzyme USP2 and its upstream regulators (PGC-1α and β-catenin), and the subsequent enhancement of mTOR-related autophagy which is regulated by USP2. These findings suggested that acute stress dampened AMPA receptor expression by controlling USP2-related signaling, which caused the detrimental effect on hippocampus-dependent cognitive processes. We also found that retigabine alleviated acute stress-induced spatial memory retrieval impairment through adjusting the aberrance of USP2, its upstream regulators (PGC-1α, E4BP4 and β-catenin) and its downstream targets (mTOR, autophagy and GluA1). Our results have identified USP2 as a key molecule that mediates stress-induced spatial memory retrieval impairment, which provides a framework for new druggable targets to conceptually treat stress-associated cognitive deficits. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. RAAS and stress markers in acute ischemic stroke: preliminary findings.

    PubMed

    Back, C; Thiesen, K L; Skovgaard, K; Edvinsson, L; Jensen, L T; Larsen, V A; Iversen, H K

    2015-02-01

    Angiotensin II type 1 receptor blockade has neuroprotective effects in animal stroke models, but no effects in clinical stroke trials. We evaluated cerebral and peripheral changes in the renin angiotensin aldosterone system (RAAS) and stress responses in acute ischemic stroke patients. Blood from a jugular and cubital vein was collected within 48 h of stroke onset, after 24 and 48 h, and renin, angiotensin I, angiotensin II, aldosterone, norepinephrine, epinephrine, and cortisol were measured. Post-stroke cubital vein samples were collected after 8 (4.7-10) months. The acute systolic blood pressure was significantly increased, 148 (141-168) vs 140 (130-147) mmHg post-stroke. Angiotensin I, renin and aldosterone levels were significantly lower, angiotensin II was unchanged, and ACE activity was higher in the acute phase compared to post-stroke. No differences in RAAS were detected between jugular and cubital plasma levels. Jugular venous plasma levels of epinephrine and cortisol were elevated in the acute phase compared to cubital levels (P < 0.05). Increased epinephrine and cortisol levels in the jugular vein blood may reflect a higher peripheral turnover. The observed changes in RAAS in the acute stroke phase are consistent with responses to increased blood pressure. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Verapamil enhances acute stress or glucocorticoid-induced deficits in retrieval of long-term memory in rats.

    PubMed

    Rashidy-Pour, Ali; Vafaei, Abbas Ali; Taherian, Abbas Ali; Miladi-Gorji, Hossein; Sadeghi, Hassan; Fathollahi, Yaghoub; Bandegi, Ahmad Reza

    2009-10-12

    This study was designed to investigate an interaction between acute restraint stress and corticosterone with verapamil, a blocker of L-type voltage-dependent calcium (VDC) channels on retrieval of long-term memory. Young adult male rats were trained in one trial inhibitory avoidance task (0.5 mA, 3 s footshock). On retention test given 48 h after training, the latency to re-enter dark compartment of the apparatus was recorded. In Experiment 1, verapamil pretreatment (5, 10, or 20 mg/kg) enhanced the impairing effects of acute stress (which was applied for 10 min in a Plexiglass tube 30 min before the retention test) on memory retrieval. The applied stress increased circulating corticosterone levels as assessed immediately after the retention test, indicating that stress-induced impairment of memory retrieval is mediated, in part, by increased plasma levels of glucocorticoids. Verapamil did not change this response. In Experiment 2, pretreatment of an intermediate dose of verapamil also enhanced corticosterone-induced impairment of memory retrieval. In Experiments 3 and 4, acute stress or corticosterone did not change motor activity with or without prior treatment of verapamil, suggesting that stress or glucocorticoid-induced impairment of memory retrieval is not due to any gross disturbances in motor performance of animals. These findings indicate that blockade of L-type VDC channels enhances stress or glucocorticoid-induced impairment of memory retrieval, and provide evidence for the existence of an interaction between glucocorticoids and L-type VDC channels on memory retrieval.

  14. Understanding recovery in children following traffic-related injuries: exploring acute traumatic stress reactions, child coping, and coping assistance.

    PubMed

    Marsac, Meghan L; Donlon, Katharine A; Hildenbrand, Aimee K; Winston, Flaura K; Kassam-Adams, Nancy

    2014-04-01

    Millions of children incur potentially traumatic physical injuries every year. Most children recover well from their injury but many go on to develop persistent traumatic stress reactions. This study aimed to describe children's coping and coping assistance (i.e., the ways in which parents and peers help children cope) strategies and to explore the association between coping and acute stress reactions following an injury. Children (N = 243) rated their acute traumatic stress reactions within one month of injury and reported on coping and coping assistance six months later. Parents completed a measure of coping assistance at the six-month assessment. Children used an average of five to six coping strategies (out of 10), with wishful thinking, social support, and distraction endorsed most frequently. Child coping was associated with parent and peer coping assistance strategies. Significant acute stress reactions were related to subsequent child use of coping strategies (distraction, social withdrawal, problem-solving, blaming others) and to child report of parent use of distraction (as a coping assistance strategy). Findings suggest that children's acute stress reactions may influence their selection of coping and coping assistance strategies. To best inform interventions, research is needed to examine change in coping behaviors and coping assistance over time, including potential bidirectional relationships between trauma reactions and coping.

  15. Evaluating the Impact of a Brief Artistic Intervention on Cardiovascular Recovery from Acute Stress

    ERIC Educational Resources Information Center

    Keogh, Katharina; Creaven, Ann-Marie

    2017-01-01

    In this study we tested whether drawing and coloring influence cardiovascular recovery and perceived stress following exposure to a stressor. In a mixed experimental design, participants (N = 62) completed an acute stress task before being randomly assigned to one of three brief activities: free-form drawing (full creative control), coloring…

  16. [Response and adaptation of photosynthesis of cucumber seedlings to high temperature stress].

    PubMed

    Sun, Sheng Nan; Wang, Qiang; Sun, Chen Chen; Liu, Feng Jiao; Bi, Huan Gai; Ai, Xi Zhen

    2017-05-18

    Cucumber seedlings (Cucumis sativus Jinyou 35) were used to study the effects of high temperature (HT: 42 ℃/32 ℃) and sub-high temperature (SHT: 35 ℃/25 ℃) on its photosynthesis and growth. The results showed that the growth of cucumber seedlings was dramatically inhibited by the high and sub-high temperature stresses. The photosynthetic rate (P n ) was gradually reduced, while intercellular CO 2 concentration (C i ) was increased as heat stress lasted. Under heat stress, stomatal conductance (g s ), transpiration rate (T r ), photorespiration rate (P r ) and dark respiration rate (D r ) showed a trend from rise to decline in cucumber seedlings, which implied that heat-induced decline of photosynthesis was mainly due to non-stomatal limitation. Maximal photochemical efficiency of PS2 in darkness (F v /F m ), actual photochemical efficiency (χ PS 2 ), photochemical quenching (q P ) and electron transport rate (ETR) were severely hampered, while initial fluorescence (F o ) and non-chemical quenching (NPQ) were increased as a result of high and sub-high temperature stresses. Under extended high temperature stress, the activities of RuBP carboxylase (RuBPCase) and Rubisco activase (RCA) as well as the mRNA abundance of Rubisco and RCA were in the trend of decrease, while they were reduced 3 days following the sub-high temperature treatment. The activities and mRNA expressions of sedoheptulose-1,7-bisphosphatase (SBPase) and fructose 1,6-bisphosphate aldolase (FBA) increased initially, but decreased afterwards under heat stress. Taken together, our data suggested that short-term sub-high temperature did not cause photoinhibition under optimal light conditions, however, high temperature led to severe damage to PS2 reaction center in cucumber seedlings. The photosynthetic enzymes were induced by high temperature stress and the induction was affected by temperature and stress duration.

  17. Sex differences in perceived stress and early recovery in young and middle-aged patients with acute myocardial infarction.

    PubMed

    Xu, Xiao; Bao, Haikun; Strait, Kelly; Spertus, John A; Lichtman, Judith H; D'Onofrio, Gail; Spatz, Erica; Bucholz, Emily M; Geda, Mary; Lorenze, Nancy P; Bueno, Héctor; Beltrame, John F; Krumholz, Harlan M

    2015-02-17

    Younger age and female sex are both associated with greater mental stress in the general population, but limited data exist on the status of perceived stress in young and middle-aged patients presenting with acute myocardial infarction. We examined sex difference in stress, contributing factors to this difference, and whether this difference helps explain sex-based disparities in 1-month recovery using data from 3572 patients with acute myocardial infarction (2397 women and 1175 men) 18 to 55 years of age. The average score of the 14-item Perceived Stress Scale at baseline was 23.4 for men and 27.0 for women (P<0.001). Higher stress in women was explained largely by sex differences in comorbidities, physical and mental health status, intrafamily conflict, caregiving demands, and financial hardship. After adjustment for demographic and clinical characteristics, women had worse recovery than men at 1 month after acute myocardial infarction, with mean differences in improvement score between women and men ranging from -0.04 for EuroQol utility index to -3.96 for angina-related quality of life (P<0.05 for all). Further adjustment for baseline stress reduced these sex-based differences in recovery to -0.03 to -3.63, which, however, remained statistically significant (P<0.05 for all). High stress at baseline was associated with significantly worse recovery in angina-specific and overall quality of life, as well as mental health status. The effect of baseline stress on recovery did not vary between men and women. Among young and middle-aged patients, higher stress at baseline is associated with worse recovery in multiple health outcomes after acute myocardial infarction. Women perceive greater psychological stress than men at baseline, which partially explains women's worse recovery. © 2015 American Heart Association, Inc.

  18. Relationship between general intelligence, emotional intelligence, stress levels and stress reactivity.

    PubMed

    Singh, Yogesh; Sharma, Ratna

    2012-07-01

    Stressful life events and daily life stresses have both deleterious and cumulative effects on human body. In several studies, stress has been shown to affect various parameter of higher mental function like attention, concentration, learning and memory. Present study was designed to explore the relationship among GI level, EI level, psychological stress levels and acute stress reactivity in young normal healthy subjects. The study was conducted on thirty four healthy male student volunteers to study a) acute stress reactivity in subjects with varying levels of General Intelligence (GI) and Emotional Intelligence (EI) and b) correlation between GI, EI, acute stress and perceived stress. Baseline GI and EI and acute stress and perceived stress scores were measured by standard assessment scales. Using median value of GI and EI scores as cutoff values, subjects were categorized into four groups. Among different GI-EI groups, acute stress reactivity was similar but salivary Cortisol (especially post stressor level) and perceived stress level was a differentiating factor. High level of EI was associated inversely with acute and chronic perceived stress level. Significant correlation was found between acute and chronic perceived stress levels. Level of general intelligence showed no relation to acute or chronic stress levels as well as acute stress reactivity. The differences in various groups of GI and EI had no effect on the baseline and post stress performance on Sternberg memory test and all the three conditions of Stroop test. In conclusion emotional intelligence as an attribute is better suited to handle day to day acute stress and chronic perceived stress.

  19. Enhanced startle responsivity 24 hours after acute stress exposure.

    PubMed

    Herten, Nadja; Otto, Tobias; Adolph, Dirk; Pause, Bettina M; Kumsta, Robert; Wolf, Oliver T

    2016-10-01

    Cortisol release in a stressful situation can be beneficial for memory encoding and memory consolidation. Stimuli, such as odors, related to the stressful episode may successfully cue memory contents of the stress experience. The current investigation aimed at testing the potency of stress to influence startle responsivity 24 hr later and to implicitly reactivate emotional memory traces triggered by an odor involved. Participants were assigned to either a stress (Trier Social Stress Test [TSST]) or control (friendly TSST [f-TSST]) condition featuring an ambient odor. On the next day, participants underwent an auditory startle paradigm while their eyeblink reflex was recorded by an electrooculogram. Three different olfactory stimuli were delivered, one being the target odor presented the day before. Additionally, negative, positive, and pictures of the committee members were included for comparing general startle responsivity and fear-potentiated startle. Participants of the stress group demonstrated an enhanced startle response across all stimuli compared to participants of the control group. There were no specific effects with regard to the target odor. The typical fear-potentiated startle response occurred. Stressed participants tended to rate the target odor more aversive than control participants. Odor recognition memory did not differ between the groups, suggesting an implicit effect on odor valence. Our results show that acute stress exposure enhances startle responsivity 24 hr later. This effect might be caused by a shift of amygdala function causing heightened sensitivity, but lower levels of specificity. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  20. Water Stress Detection using Temperature, Emissivity, and Reflectance

    NASA Astrophysics Data System (ADS)

    Gerhards, Max; Rock, Gilles; Schlerf, Martin; Udelhoven, Thomas

    2017-04-01

    Water stress is one of the most critical abiotic stressors limiting crop development. The main imaging and non-imaging remote sensing based techniques for the detection of plant stress (water stress and other types of stress) are thermography, visible (VIS), near- and shortwave infrared (NIR/SWIR) reflectance, and fluorescence. Just very recently, in addition to broadband thermography, narrowband (hyperspectral) thermal imaging has become available, which even facilitates the retrieval of spectral emissivity as an additional measure of plant stress. It is, however, still unclear at what stage plant stress is detectable with the various techniques. During summer 2014 a water treatment experiment was run on 60 potato plants (Solanum tuberosum L. Cilena) with one half of the plants watered and the other half stressed. Crop response was measured using broadband and hyperspectral thermal cameras and a VNIR/SWIR spectrometer. Stomatal conductance was measured using a leaf porometer. Various measures and indices were computed and analysed for their sensitivity towards water stress (Crop Water Stress Index (CWSI), Moisture Stress Index (MSI), Photochemical Reflectance Index (PRI), and spectral emissivity, amongst others). The results show that water stress as measured through stomatal conductance started on day 2 after watering was stopped. The fastest reacting, i.e., starting on day 7, indices were temperature based measures (e.g., CWSI) and NIR/SWIR reflectance based indices related to plant water content (e.g., MSI). Spectral emissivity reacted equally fast. Contrarily, visual indices (e.g., PRI) either did not respond at all or responded in an inconsistent manner. This experiment shows that pre-visual water stress detection is feasible using indices depicting leaf temperature, leaf water content and spectral emissivity.

  1. Acute changes in community violence and increases in hospital visits and deaths from stress-responsive diseases.

    PubMed

    Ahern, Jennifer; Matthay, Ellicott C; Goin, Dana E; Farkas, Kriszta; Rudolph, Kara E

    2018-06-06

    Community violence may affect a broad range of health outcomes through physiologic stress responses and changes in health behaviors among residents. However, existing research on the health impacts of community violence suffers from problems with bias. We examined the relations of acute changes in community violence with hospital visits and deaths due to stress-responsive diseases (mental, respiratory, and cardiac conditions) in statewide data from California 2005-2013. The community violence exposure was measured as both binary spikes and continuous acute changes. We applied a combined fixed-effects and time-series design that separates the effects of violence from those of community- and individual-level confounders more effectively than past research. Temporal patterning was removed from community violence rates and disease rates in each place using a Kalman smoother, resulting in residual rates. We used linear regression with place fixed-effects to examine within-place associations of acute changes in community violence with residual rates of each outcome, controlling for local time-varying covariates. We found acute increases in hospital visits and deaths due to anxiety disorders (0.31 per 100,000; 95% Confidence Interval (CI) 0.02,0.59), substance use (0.47 per 100,000; 95%CI 0.14,0.80), asthma (0.56 per 100,000; 95%CI 0.16,0.95), and fatal acute myocardial infarction (0.09 per 100,000; 95%CI 0.00,0.18) co-occurring with violence spikes. The pattern of findings was similar for the exposure of continuous acute violence changes. Although the associations were small, the identified increases in stress-responsive conditions suggest the possibility of health impacts of acute changes in community violence.

  2. Acute Exercise and Oxidative Stress: CrossFit(™) vs. Treadmill Bout.

    PubMed

    Kliszczewicz, Brian; Quindry, C John; Blessing, L Daniel; Oliver, D Gretchen; Esco, R Michael; Taylor, J Kyle

    2015-09-29

    CrossFit(™), a popular high-intensity training modality, has been the subject of scrutiny, with concerns of elevated risk of injury and health. Despite these concerns empirical evidence regarding physiologic stresses including acute oxidative stress is lacking. Therefore, the purpose of this investigation was to examine the acute redox response to a CrossFit(™) bout. Furthermore, these findings were compared to a high-intensity treadmill bout as a point of reference. Ten males 26.4 ± 2.7 yrs having three or more months of CrossFit(™) experience participated in the present study. Blood plasma was collected at four time points: Pre-exercise (PRE), immediately-post-exercise (IPE), 1 hr-post (1-HP) and 2 hr-post (2-HP), to examine oxidative damage and antioxidant capacity. Regarding plasma oxidative damage, CrossFit(™) and Treadmill elicited a time-dependent increase of lipid peroxides 1-HP (CrossFit(™)=+143%, Treadmill=+115%) and 2-HP (CrossFit(™)=+256%, Treadmill+167%). Protein Carbonyls were increased IPE in CF only (+5%), while a time-dependent decrease occurred 1-HP (CrossFit(™)=-16%, Treadmill=-8%) and 2-HP (CF=-16%, TM=-1%) compared to IPE. Regarding antioxidant capacity, Ferric Reducing Antioxidant Power also demonstrated a time-dependent increase within CrossFit(™) and Treadmill: IPE (CrossFit(™)=+25%, Treadmill=+17%), 1-HP (CrossFit(™)=+26%, Treadmill=+4.8%), 2-HP (CrossFit(™)=+20%, Treadmill=+12%). Total Enzymatic Antioxidant Capacity showed a time-dependent decrease in IPE (CrossFit(™)=-10%, Treadmill=-12%), 1-HP (CrossFit(™)=-12%, Treadmill=-6%), 2-HP (CrossFit(™)=-7%, Treadmill=-11%). No trial-dependent differences were observed in any biomarker of oxidative stress. The CrossFit(™) bout elicited an acute blood oxidative stress response comparable to a traditional bout of high-intensity treadmill running. Results also confirm that exercise intensity and the time course of exercise recovery influence oxidative responses.

  3. Sex hormones affect acute and chronic stress responses in sexually dimorphic patterns: Consequences for depression models.

    PubMed

    Guo, Lei; Chen, Yi-Xi; Hu, Yu-Ting; Wu, Xue-Yan; He, Yang; Wu, Juan-Li; Huang, Man-Li; Mason, Matthew; Bao, Ai-Min

    2018-05-21

    Alterations in peripheral sex hormones may play an important role in sex differences in terms of stress responses and mood disorders. It is not yet known whether and how stress-related brain systems and brain sex steroid levels fluctuate in relation to changes in peripheral sex hormone levels, or whether the different sexes show different patterns. We aimed to investigate systematically, in male and female rats, the effect of decreased circulating sex hormone levels following gonadectomy on acute and chronic stress responses, manifested as changes in plasma and hypothalamic sex steroids and hypothalamic stress-related molecules. Experiment (Exp)-1: Rats (14 males, 14 females) were gonadectomized or sham-operated (intact); Exp-2: gonadectomized and intact rats (28 males, 28 females) were exposed to acute foot shock or no stressor; and Exp-3: gonadectomized and intact rats (32 males, 32 females) were exposed to chronic unpredictable mild stress (CUMS) or no stressor. For all rats, plasma and hypothalamic testosterone (T), estradiol (E2), and the expression of stress-related molecules were determined, including corticotropin-releasing hormone, vasopressin, oxytocin, aromatase, and the receptors for estrogens, androgens, glucocorticoids, and mineralocorticoids. Surprisingly, no significant correlation was observed in terms of plasma sex hormones, brain sex steroids, and hypothalamic stress-related molecule mRNAs (p > 0.113) in intact or gonadectomized, male or female, rats. Male and female rats, either intact or gonadectomized and exposed to acute or chronic stress, showed different patterns of stress-related molecule changes. Diminished peripheral sex hormone levels lead to different peripheral and central patterns of change in the stress response systems in male and female rats. This has implications for the choice of models for the study of the different types of mood disorders which also show sex differences. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Measurement of the temperature-dependent threshold shear-stress of red blood cell aggregation.

    PubMed

    Lim, Hyun-Jung; Nam, Jeong-Hun; Lee, Yong-Jin; Shin, Sehyun

    2009-09-01

    Red blood cell (RBC) aggregation is becoming an important hemorheological parameter, which typically exhibits temperature dependence. Quite recently, a critical shear-stress was proposed as a new dimensional index to represent the aggregative and disaggregative behaviors of RBCs. The present study investigated the effect of the temperature on the critical shear-stress that is required to keep RBC aggregates dispersed. The critical shear-stress was measured at various temperatures (4, 10, 20, 30, and 37 degrees C) through the use of a transient microfluidic aggregometry. The critical shear-stress significantly increased as the blood temperature lowered, which accorded with the increase in the low-shear blood viscosity with the lowering of the temperature. Furthermore, the critical shear-stress also showed good agreement with the threshold shear-stress, as measured in a rotational Couette flow. These findings assist in rheologically validating the critical shear-stress, as defined in the microfluidic aggregometry.

  5. Acute Stress Suppresses Synaptic Inhibition and Increases Anxiety via Endocannabinoid Release in the Basolateral Amygdala

    PubMed Central

    Itoga, Christy A.; Fisher, Marc O.; Solomonow, Jonathan; Roltsch, Emily A.; Gilpin, Nicholas W.

    2016-01-01

    Stress and glucocorticoids stimulate the rapid mobilization of endocannabinoids in the basolateral amygdala (BLA). Cannabinoid receptors in the BLA contribute to anxiogenesis and fear-memory formation. We tested for rapid glucocorticoid-induced endocannabinoid regulation of synaptic inhibition in the rat BLA. Glucocorticoid application to amygdala slices elicited a rapid, nonreversible suppression of spontaneous, but not evoked, GABAergic synaptic currents in BLA principal neurons; the effect was also seen with a membrane-impermeant glucocorticoid, but not with intracellular glucocorticoid application, implicating a membrane-associated glucocorticoid receptor. The glucocorticoid suppression of GABA currents was not blocked by antagonists of nuclear corticosteroid receptors, or by inhibitors of gene transcription or protein synthesis, but was blocked by inhibiting postsynaptic G-protein activity, suggesting a postsynaptic nongenomic steroid signaling mechanism that stimulates the release of a retrograde messenger. The rapid glucocorticoid-induced suppression of inhibition was prevented by blocking CB1 receptors and 2-arachidonoylglycerol (2-AG) synthesis, and it was mimicked and occluded by CB1 receptor agonists, indicating it was mediated by the retrograde release of the endocannabinoid 2-AG. The rapid glucocorticoid effect in BLA neurons in vitro was occluded by prior in vivo acute stress-induced, or prior in vitro glucocorticoid-induced, release of endocannabinoid. Acute stress also caused an increase in anxiety-like behavior that was attenuated by blocking CB1 receptor activation and inhibiting 2-AG synthesis in the BLA. Together, these findings suggest that acute stress causes a long-lasting suppression of synaptic inhibition in BLA neurons via a membrane glucocorticoid receptor-induced release of 2-AG at GABA synapses, which contributes to stress-induced anxiogenesis. SIGNIFICANCE STATEMENT We provide a cellular mechanism in the basolateral amygdala (BLA) for

  6. In vivo aerobic metabolism of the rainbow trout gut and the effects of an acute temperature increase and stress event.

    PubMed

    Brijs, Jeroen; Gräns, Albin; Hjelmstedt, Per; Sandblom, Erik; van Nuland, Nicole; Berg, Charlotte; Axelsson, Michael

    2018-05-24

    The fish gut is responsible for numerous potentially energetically costly processes, yet, little is known about its metabolism. Here, we provide the first in vivo measurements for aerobic metabolism of the gut in a teleost fish by measuring gut blood flow, as well as arterial and portal venous oxygen content. At 10°C, gut oxygen uptake rates were 4.3±0.5 ml O 2 h -1 kg -1 (∼11% of whole animal oxygen uptake). Following acute warming to 15°C, gut blood flow increased ∼3.4-fold and gut oxygen uptake rate increased ∼3.7-fold (16.0±3.3 ml O 2 h -1 kg -1 ), now representing ∼25% of whole animal oxygen uptake. Although gut blood flow decreased following an acute stress event at 15°C, gut oxygen uptake remained unchanged due to a ∼2-fold increase in oxygen extraction. The high metabolic thermal sensitivity of the gut discovered here could have important implications on the overall aerobic capacity and performance of fish and warrants further investigations. © 2018. Published by The Company of Biologists Ltd.

  7. Effects of acute psychological stress on placebo and nocebo responses in a clinically relevant model of visceroception.

    PubMed

    Roderigo, Till; Benson, Sven; Schöls, Margarita; Hetkamp, Madeleine; Schedlowski, Manfred; Enck, Paul; Elsenbruch, Sigrid

    2017-08-01

    There is evidence to suggest a role of emotions in placebo and nocebo effects, but whether acute psychological stress changes the magnitude of placebo or nocebo responses has not been tested. In a clinically relevant model of visceroception, we assessed effects of acute psychological stress on changes in urgency and pain in response to positive or negative treatment suggestions. In 120 healthy volunteers, perceived urge-to-defecate and pain in response to individually calibrated rectal distensions were measured with visual analogue scales during a BASELINE. Participants then underwent the Trier Social Stress Test (N = 60) or a simple cognitive task (control, N = 60) and were randomized to positive (placebo), negative (nocebo), or neutral treatment information regarding intravenous administration of saline. The series of distensions was repeated, and changes in visual analogue scales from BASELINE to TEST were compared between groups using analysis of covariance and planned post hoc tests. Treatment information emerged as a main factor (P <0.001), supporting treatment information effects for both urgency and pain. Effects for urgency were modulated by stress (interaction effect: P <0.05): Positive information reduced urgency (P = 0.025), while negative information increased urgency (P = 0.026) only in stressed groups. For pain, effects of stress emerged for nocebo responses, which were only evident in stressed groups (P = 0.009). This is the first experimental study supporting effects of acute psychological stress on placebo and nocebo responses in visceroception. Results call for mechanistic as well as patient studies to assess how psychological stress shapes patients' treatment expectations and thereby affects health outcomes.

  8. The Estrous Cycle of the Ewe Is Resistant to Disruption by Repeated, Acute Psychosocial Stress1

    PubMed Central

    Wagenmaker, Elizabeth R.; Breen, Kellie M.; Oakley, Amy E.; Tilbrook, Alan J.; Karsch, Fred J.

    2010-01-01

    Five experiments were conducted to test the hypothesis that psychosocial stress interferes with the estrous cycle of sheep. In experiment 1, ewes were repeatedly isolated during the follicular phase. Timing, amplitude, and duration of the preovulatory luteinizing hormone (LH) surge were not affected. In experiment 2, follicular-phase ewes were subjected twice to a “layered stress” paradigm consisting of sequential, hourly application of isolation, restraint, blindfold, and predator cues. This reduced the LH pulse amplitude but did not affect the LH surge. In experiment 3, different acute stressors were given sequentially within the follicular phase: food denial plus unfamiliar noises and forced exercise, layered stress, exercise around midnight, and transportation. This, too, did not affect the LH surge. In experiment 4, variable acute psychosocial stress was given every 1–2 days for two entire estrous cycles; this did not disrupt any parameter of the cycle monitored. Lastly, experiment 5 examined whether the psychosocial stress paradigms of experiment 4 would disrupt the cycle and estrous behavior if sheep were metabolically stressed by chronic food restriction. Thirty percent of the food-restricted ewes exhibited deterioration of estrous cycle parameters followed by cessation of cycles and failure to express estrous behavior. However, disruption was not more evident in ewes that also encountered psychosocial stress. Collectively, these findings indicate the estrous cycle of sheep is remarkably resistant to disruption by acute bouts of psychosocial stress applied intermittently during either a single follicular phase or repeatedly over two estrous cycles. PMID:20164438

  9. Self-reported racial discrimination and endothelial reactivity to acute stress in women.

    PubMed

    Wagner, Julie A; Tennen, Howard; Finan, Patrick H; Ghuman, Nimrta; Burg, Matthew M

    2013-08-01

    This study investigated the effect of self-reported racial discrimination on endothelial responses to acute laboratory mental stress among post-menopausal women. One-hundred thirteen women (n = 94 self-identified as White and n = 19 self-identified as racial/ethnic minority), 43% with type 2 diabetes, reported lifetime experiences of racial/ethnic discrimination. Repeated assessments of flow-mediated dilation were performed at baseline, immediately after 5 min of mental arithmetic and at 20-min recovery. Both White and racial/ethnic minority women reported lifetime discrimination, with rates significantly higher among minorities. Self-reported lifetime discrimination was associated with attenuated flow-mediated dilation at recovery. Confounding variables, including clinical characteristics, mood, personality traits, other life stressors and general distress, did not better account for the effect of racial discrimination. Neither race/ethnicity nor diabetes status moderated the effect. The perceived stressfulness of the mental arithmetic was not associated with the endothelial response. In conclusion, self-reported lifetime discrimination is associated with attenuated endothelial recovery from acute mental stress. Elucidating the effects of discrimination and the biological mechanisms through which it affects the vasculature may suggest interventions to improve health. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Noni (Morinda citrifolia) Modulates the Hypothalamic Expression of Stress- and Metabolic-Related Genes in Broilers Exposed to Acute Heat Stress

    PubMed Central

    Rajaei-Sharifabadi, Hossein; Ellestad, Laura; Porter, Tom; Donoghue, Annie; Bottje, Walter G.; Dridi, Sami

    2017-01-01

    Heat stress (HS) adversely affects growth performance and inflicts heavy economic losses to the poultry industry. There is, therefore, a critical need to identify new alternative strategies to alleviate the negative effects induced by HS. The tropic medicinal plant, Morinda citrifolia (Noni), is being used in livestock nutrition, however the literature is limited and conflicting for its impact on growth performance. The present study aimed to determine the effect of Noni on feeding and drinking behavior as well as on the hypothalamic expression of stress- and metabolic-related genes in broiler chickens exposed to acute HS. A total of 480 1 day-old male broiler chicks were randomly assigned to 12 controlled environmental chambers. Birds were subjected to two environmental conditions (TN, 25°C vs. HS, 35°C for 2 h) and fed two diets (control vs. 0.2% Noni) in a 2 × 2 factorial design. Feed intake and core body temperature (BT) were recorded during HS period. Blood was collected and hypothalamic tissues were harvested for target gene and protein analyses. Acute HS-broilers exhibited higher BT (~1°C), spent less time eating with a significant decrease in feed intake, and spent more time drinking along with higher drinking frequency compared to those maintained under TN conditions. Although Noni supplementation did not improve feed intake, it significantly delayed (~30 min) and reduced the BT-induced by HS. At molecular levels and under HS conditions, Noni supplementation down regulated the hypothalamic expression of HSP90 and its related transcription factors HSF1, 2, and 4, increased orexin mRNA levels, and decreased the phosphorylation levels of AMPKα1/2Thr172 and mTORSer2481. Together, these data indicated that Noni supplementation might modulate HS response in broilers through central orexin-AMPK-mTOR pathways. PMID:29259622

  11. Noni (Morinda citrifolia) Modulates the Hypothalamic Expression of Stress- and Metabolic-Related Genes in Broilers Exposed to Acute Heat Stress.

    PubMed

    Rajaei-Sharifabadi, Hossein; Ellestad, Laura; Porter, Tom; Donoghue, Annie; Bottje, Walter G; Dridi, Sami

    2017-01-01

    Heat stress (HS) adversely affects growth performance and inflicts heavy economic losses to the poultry industry. There is, therefore, a critical need to identify new alternative strategies to alleviate the negative effects induced by HS. The tropic medicinal plant, Morinda citrifolia (Noni), is being used in livestock nutrition, however the literature is limited and conflicting for its impact on growth performance. The present study aimed to determine the effect of Noni on feeding and drinking behavior as well as on the hypothalamic expression of stress- and metabolic-related genes in broiler chickens exposed to acute HS. A total of 480 1 day-old male broiler chicks were randomly assigned to 12 controlled environmental chambers. Birds were subjected to two environmental conditions (TN, 25°C vs. HS, 35°C for 2 h) and fed two diets (control vs. 0.2% Noni) in a 2 × 2 factorial design. Feed intake and core body temperature (BT) were recorded during HS period. Blood was collected and hypothalamic tissues were harvested for target gene and protein analyses. Acute HS-broilers exhibited higher BT (~1°C), spent less time eating with a significant decrease in feed intake, and spent more time drinking along with higher drinking frequency compared to those maintained under TN conditions. Although Noni supplementation did not improve feed intake, it significantly delayed (~30 min) and reduced the BT-induced by HS. At molecular levels and under HS conditions, Noni supplementation down regulated the hypothalamic expression of HSP90 and its related transcription factors HSF1, 2, and 4, increased orexin mRNA levels, and decreased the phosphorylation levels of AMPKα1/2 Thr172 and mTOR Ser2481 . Together, these data indicated that Noni supplementation might modulate HS response in broilers through central orexin-AMPK-mTOR pathways.

  12. Chronic Stress Enhances the Corticosterone Response and Neurotoxicity to +3,4-Methylenedioxymethamphetamine (MDMA): The Role of Ambient Temperature

    PubMed Central

    Johnson, Bethann N.

    2010-01-01

    Stress facilitates drug abuse by humans. In rodents, stress enhances the neurochemical, neuroendocrine, and behavioral responses to psychostimulants. Although chronic unpredictable stress (CUS) enhances the acute hyperthermic and long-term monoamine-depleting effects of the psychostimulant +3,4-methylenedioxymethamphetamine (MDMA), the roles of hyperthermia and corticosterone (CORT) in mediating the stress-induced enhancement of MDMA-induced serotonin (5-HT) and dopamine (DA) depletions are unknown. Rats were exposed to 10 days of CUS and then challenged with MDMA (5 mg/kg i.p. once every 2 h for a total of four injections). Prior exposure to CUS augmented MDMA-induced hyperthermia and plasma CORT secretion and the long-term depletions in 5-HT content in striatum, hippocampus, and frontal cortex and DA content in striatum. A reduced ambient temperature of 21°C attenuated the hyperthermia, CORT secretion, and 5-HT decreases after MDMA in nonstressed rats. The lower ambient temperature also prevented the augmented hyperthermia, CORT secretion, and enhanced 5-HT and DA depletions after MDMA in chronically stressed rats to levels exhibited by nonstressed, MDMA-treated rats. To investigate the role of CORT on monoamine depletions in response to MDMA, stressed and nonstressed rats were treated with the CORT synthesis inhibitor metyrapone during exposure to MDMA. Metyrapone prevented CORT secretion in both stressed and nonstressed rats but did not modify 5-HT or DA depletions in any brain region examined. This study suggests that enhanced CORT is a consequence of enhanced hyperthermia and the CUS-induced enhancements of MDMA-induced monoamine depletions may be mediated by hyperthermia but not CORT. PMID:20634423

  13. Association Between Interleukin-6 and Striatal Prediction-Error Signals Following Acute Stress in Healthy Female Participants.

    PubMed

    Treadway, Michael T; Admon, Roee; Arulpragasam, Amanda R; Mehta, Malavika; Douglas, Samuel; Vitaliano, Gordana; Olson, David P; Cooper, Jessica A; Pizzagalli, Diego A

    2017-10-15

    Stress is widely known to alter behavioral responses to rewards and punishments. It is believed that stress may precipitate these changes through modulation of corticostriatal circuitry involved in reinforcement learning and motivation, although the intervening mechanisms remain unclear. One candidate is inflammation, which can rapidly increase following stress and can disrupt dopamine-dependent reward pathways. Here, in a sample of 88 healthy female participants, we first assessed the effect of an acute laboratory stress paradigm on levels of plasma interleukin-6 (IL-6), a cytokine known to be both responsive to stress and elevated in depression. In a second laboratory session, we examined the effects of a second laboratory stress paradigm on reward prediction error (RPE) signaling in the ventral striatum. We show that individual differences in stress-induced increases in IL-6 (session 1) were associated with decreased ventral striatal RPE signaling during reinforcement learning (session 2), though there was no main effect of stress on RPE. Furthermore, changes in IL-6 following stress predicted intraindividual variability in perceived stress during a 4-month follow-up period. Taken together, these data identify a novel link between IL-6 and striatal RPEs during reinforcement learning in the context of acute psychological stress, as well as future appraisal of stressful life events. Copyright © 2017 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  14. Comparison of three acute stress models for simulating the pathophysiology of stress-related mucosal disease.

    PubMed

    Saxena, Bhagawati; Singh, Sanjay

    2017-05-30

    Stress-related mucosal disease (SRMD) is highly prevalent in intensive care patients leading to increasing treatment cost and mortality. SRMD is a disease elusive of ideal treatment. Evaluation of drugs is very pertinent for the efficient and safe treatment of SRMD. It relies mainly on in vivo screening models. There are various stress models, and till date, none of them is validated for simulating the SRMD pathophysiology. The present study aims to choose the best model, which reproduce pathophysiology of SRMD, among previously established stress models. This study evaluates ulcer index, hexosamine content, microvascular permeability, and gastric content in three acute stress models (cold-restraint, restraint, and water immersion restraint). Macroscopic pictures of the ulcerogenic stomach explain that in contrast to other models, cold-restraint stress (CRS) exposure produced marked ulcers on the fundic area of the stomach. Results of the present study depicted that each stress model significantly increased ulcer index, microvascular permeability and decreased hexosamine level, however, the maximum in the case of CRS-exposed rats. Total acidity and pH of the gastric content remains unchanged in all the stress models. On the contrary, the gastric volume significantly decreased only in case of CRS, while unchanged in other stress models. The overall results revealed that the CRS resembles the pathophysiology of SRMD closely. It is the best and feasible model among all the models to evaluate drugs for the treatment of SRMD.

  15. Effects of a Dissostichus mawsoni-CaM recombinant proteins feed additive on the juvenile orange-spotted grouper (Epinephelus coioides) under the acute low temperature challenge.

    PubMed

    Luo, Sheng-Wei; Wang, Wei-Na; Cai, Luo; Qi, Zeng-Hua; Wang, Cong; Liu, Yuan; Peng, Chang-Lian; Chen, Liang-Biao

    2015-10-01

    The effects of Dissostichus mawsoni-Calmodulin (Dm-CaM) on growth performance, enzyme activities, respiratory burst, MDA level and immune-related gene expressions of the orange-spotted grouper (Epinephelus coioides) exposed to the acute low temperature stress were evaluated. The commercial diet supplemented with Dm-CaM protein was fed to the groupers for 6 weeks. No significant difference was observed in the specific growth rates, weight gains and survivals. After the feeding trial, the groupers were exposed to acute low temperature challenge. The groupers fed with Dm-CaM additive diet showed a significant decrease in the respiratory burst activity, while the blood cell number increased significantly at 25 °C by comparing with the control and additive control group. The enzymatic activity of SOD, ACP and ALP increased significantly in Dm-CaM additive group, while MDA level maintained stable with the lowest value. qRT-PCR analysis indicated that the up-regulated transcript expressions of CaM, C3, SOD2, LysC and HSPA4 were observed in Dm-CaM additive group. These results indicated that Dm-CaM additive diet may regulate the grouper immune response to the acute low temperature challenge.

  16. Global method for measuring stress in polymer fibers at elevated temperatures

    NASA Astrophysics Data System (ADS)

    Anagnostopoulos, G.; Andreopoulos, A. G.; Parthenios, J.; Galiotis, C.

    2005-09-01

    In this work, a methodology is presented for evaluating the interfacial shear stress as well as the corresponding axial stress in full polymer fiber reinforced materials under elevated temperatures. Its validity was confirmed by deriving interfacial shear and axial stress expressions for embedded Kevlar® 29 fibers within an epoxy matrix by means of Raman microscopy. This approach can be established to other systems such as carbon or polyethylene fiber composites, for which the observed Raman bands are both stress and temperature sensitive.

  17. Temperature stress and plant sexual reproduction: uncovering the weakest links.

    PubMed

    Zinn, Kelly E; Tunc-Ozdemir, Meral; Harper, Jeffrey F

    2010-04-01

    The reproductive (gametophytic) phase in flowering plants is often highly sensitive to hot or cold temperature stresses, with even a single hot day or cold night sometimes being fatal to reproductive success. This review describes studies of temperature stress on several crop plants, which suggest that pollen development and fertilization may often be the most sensitive reproductive stage. Transcriptome and proteomic studies on several plant species are beginning to identify stress response pathways that function during pollen development. An example is provided here of genotypic differences in the reproductive stress tolerance between two ecotypes of Arabidopsis thaliana Columbia (Col) and Hilversum (Hi-0), when reproducing under conditions of hot days and cold nights. Hi-0 exhibited a more severe reduction in seed set, correlated with a reduction in pollen tube growth potential and tropism defects. Hi-0 thus provides an Arabidopsis model to investigate strategies for improved stress tolerance in pollen. Understanding how different plants cope with stress during reproductive development offers the potential to identify genetic traits that could be manipulated to improve temperature tolerance in selected crop species being cultivated in marginal climates.

  18. The effects of acute stress and perceptual load on distractor interference.

    PubMed

    Sato, Hirotsune; Takenaka, Ippei; Kawahara, Jun I

    2012-01-01

    Selective attention can be improved under conditions in which a high perceptual load is assumed to exhaust cognitive resources, leaving scarce resources for distractor processing. The present study examined whether perceptual load and acute stress share common attentional resources by manipulating perceptual and stress loads. Participants identified a target within an array of nontargets that were flanked by compatible or incompatible distractors. Attentional selectivity was measured by longer reaction times in response to the incompatible than to the compatible distractors. Participants in the stress group participated in a speech test that increased anxiety and threatened self-esteem. The effect of perceptual load interacted with the stress manipulation in that participants in the control group demonstrated an interference effect under the low perceptual load condition, whereas such interference disappeared under the high perceptual load condition. Importantly, the stress group showed virtually no interference under the low perceptual load condition, whereas substantial interference occurred under the high perceptual load condition. These results suggest that perceptual and stress related demands consume the same attentional resources.

  19. Fear extinction deficits following acute stress associate with increased spine density and dendritic retraction in basolateral amygdala neurons.

    PubMed

    Maroun, Mouna; Ioannides, Pericles J; Bergman, Krista L; Kavushansky, Alexandra; Holmes, Andrew; Wellman, Cara L

    2013-08-01

    Stress-sensitive psychopathologies such as post-traumatic stress disorder are characterized by deficits in fear extinction and dysfunction of corticolimbic circuits mediating extinction. Chronic stress facilitates fear conditioning, impairs extinction, and produces dendritic proliferation in the basolateral amygdala (BLA), a critical site of plasticity for extinction. Acute stress impairs extinction, alters plasticity in the medial prefrontal cortex-to-BLA circuit, and causes dendritic retraction in the medial prefrontal cortex. Here, we examined extinction learning and basolateral amygdala pyramidal neuron morphology in adult male rats following a single elevated platform stress. Acute stress impaired extinction acquisition and memory, and produced dendritic retraction and increased mushroom spine density in basolateral amygdala neurons in the right hemisphere. Unexpectedly, irrespective of stress, rats that underwent fear and extinction testing showed basolateral amygdala dendritic retraction and altered spine density relative to non-conditioned rats, particularly in the left hemisphere. Thus, extinction deficits produced by acute stress are associated with increased spine density and dendritic retraction in basolateral amygdala pyramidal neurons. Furthermore, the finding that conditioning and extinction as such was sufficient to alter basolateral amygdala morphology and spine density illustrates the sensitivity of basolateral amygdala morphology to behavioral manipulation. These findings may have implications for elucidating the role of the amygdala in the pathophysiology of stress-related disorders. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  20. Cytokine profile of NALT during acute stress and its possible effect on IgA secretion.

    PubMed

    Gutiérrez-Meza, Juan Manuel; Jarillo-Luna, Rosa Adriana; Rivera-Aguilar, Victor; Miliar-García, Angel; Campos-Rodríguez, Rafael

    2017-08-01

    Stress stimuli affect the immune system responses that occur at mucosal membranes, particularly IgA secretion. It has been suggested that acute stress increases the levels of IgA and that sympathetic innervation plays an important role in this process. We herein explore in a murine model how acute stress affects the Th1/Th2/Treg cytokine balance in NALT, and the possible role of glucocorticoids in this effect. Nine-week-old male CD1 mice were divided into three groups: unstressed (control), stressed (subjected to 4h of immobilization), and stressed after pretreatment with a single dose of the corticosterone receptor antagonist RU-486. The parameters evaluated included plasma corticosterone and epinephrine, IgA levels in nasal fluid (by ELISA), the percentage of CD19 + B220 + IgA + lymphocytes and CD138 + IgA + plasma cells, and the mRNA expression of heavy α chain, J chain and pIgR. Moreover, the gene and protein expression of Th1 cytokines (TNFα, IL-2 and INF-γ), Th2 cytokines (IL-4 and IL-5) and Treg cytokines (IL-10 and TGFβ) were determined in nasal mucosa. The results show that acute stress generated a shift towards the dominance of an anti-inflammatory immune response (Th2 and Treg cytokines), evidenced by a significant rise in the amount of T cells that produce IL4, IL-5 and IL-10. This immune environment may favor IgA biosynthesis by CD138 + IgA + plasma cells, a process mediated mostly by glucocorticoids. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

  1. Acute stress disorder in older, middle-aged and younger adults in reaction to the second Lebanon war.

    PubMed

    Cohen, Miri

    2008-01-01

    To compare rate of acute stress disorder (ASD) and intensity of acute stress symptoms (ASS) in younger, middle-aged and older Israeli citizens exposed to missile attacks during the second Lebanon war. A telephone survey of a random sample of residents in the northern area of Israel was conducted in July 2006, during the third week of Lebanon war. Respondents were divided into groups aged 18-40, 41-69 and 70+. ASD and ASS were measured by the Acute Stress Interview questionnaire and by war-related exposure variables and demographic data. Exposure variables were similar in the three age groups. Older respondents reported lower intensity of ASS and obtained lower means for each of the symptoms criteria than the young adults, while the middle-aged adults were in between the younger and the older group. ASD criteria were met by 13.2% of the younger, 4.7% of middle-aged and 4.3% of older respondents (p > 0.05), and subsyndromal ASD was found in 20.5%, 14.1% and 4.4% (p < 0.05) respectively. Twenty-two percent of ASS variance was explained by younger age, female gender and higher perceived proximity to missile falling. Older adults reacted to the war situation with lower level of acute stress symptoms. Long-term effects of war on different age groups should be further studied.

  2. Growth at elevated ozone or elevated carbon dioxide concentration alters antioxidant capacity and response to acute oxidative stress in soybean (Glycine max)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gillespie, K.M.; Rogers, A.; Ainsworth, E. A.

    2011-01-31

    Soybeans (Glycine max Merr.) were grown at elevated carbon dioxide concentration ([CO{sub 2}]) or chronic elevated ozone concentration ([O{sub 3}]; 90 ppb), and then exposed to an acute O{sub 3} stress (200 ppb for 4 h) in order to test the hypothesis that the atmospheric environment alters the total antioxidant capacity of plants, and their capacity to respond to an acute oxidative stress. Total antioxidant metabolism, antioxidant enzyme activity, and antioxidant transcript abundance were characterized before, immediately after, and during recovery from the acute O{sub 3} treatment. Growth at chronic elevated [O{sub 3}] increased the total antioxidant capacity of plants,more » while growth at elevated [CO{sub 2}] decreased the total antioxidant capacity. Changes in total antioxidant capacity were matched by changes in ascorbate content, but not phenolic content. The growth environment significantly altered the pattern of antioxidant transcript and enzyme response to the acute O{sub 3} stress. Following the acute oxidative stress, there was an immediate transcriptional reprogramming that allowed for maintained or increased antioxidant enzyme activities in plants grown at elevated [O{sub 3}]. Growth at elevated [CO{sub 2}] appeared to increase the response of antioxidant enzymes to acute oxidative stress, but dampened and delayed the transcriptional response. These results provide evidence that the growth environment alters the antioxidant system, the immediate response to an acute oxidative stress, and the timing over which plants return to initial antioxidant levels. The results also indicate that future elevated [CO{sub 2}] and [O{sub 3}] will differentially affect the antioxidant system.« less

  3. Symptoms of acute stress in Jewish and Arab Israeli citizens during the Second Lebanon War.

    PubMed

    Yahav, Rivka; Cohen, Miri

    2007-10-01

    The "Second Lebanon War" exposed northern Israel to massive missile attacks, aimed at civilian centers, Jewish and Arab, for a period of several weeks. To assess prevalence of acute stress disorder (ASD) and acute stress symptoms (ASS) in Jewish and Arab samples, and their correlates with demographic and exposure variables. Telephone survey conducted in the third week of the second Lebanon war with a random sample of 133 Jewish and 66 Arab adult residents of northern Israel. ASD, ASS and symptoms-related impairment were measured by the Acute Stress Disorder Interview (ASDI) questionnaire, in addition to war-related exposure and demographic data. The majority of respondents experienced at least one of four symptom groups of ASD, 5.5% of the Jewish respondents and 20.3% of the Arabs met the criteria of ASD. Higher rates of Arab respondents reported symptoms of dissociation, reexperiencing and arousal, but a similar rate of avoidance was reported by the two samples. Higher mean scores of ASS and of symptoms-related impairment were reported by the Arab respondents. According to multiple regression analyses, younger age, female gender, Arab ethnicity and experiencing the war more intensely as a stressor significantly explained ASS variance, while Arab ethnicity and proximity to missiles exploding significantly explained the variance of symptoms-related impairment. A substantial rate of participants experienced symptoms of acute stress, while for only small proportion were the symptoms consistent with ASD. Higher ASD and ASS were reported by the Arab sample, calling attention to the need to build interventions to reduce the present symptoms and to help prepare for possible similar situations in the future.

  4. Stress analysis in high-temperature superconductors under pulsed field magnetization

    NASA Astrophysics Data System (ADS)

    Wu, Haowei; Yong, Huadong; Zhou, Youhe

    2018-04-01

    Bulk high-temperature superconductors (HTSs) have a high critical current density and can trap a large magnetic field. When bulk superconductors are magnetized by the pulsed field magnetization (PFM) technique, they are also subjected to a large electromagnetic stress, and the resulting thermal stress may cause cracking of the superconductor due to the brittle nature of the sample. In this paper, based on the H-formulation and the law of heat transfer, we can obtain the distributions of electromagnetic field and temperature, which are in qualitative agreement with experiment. After that, based on the dynamic equilibrium equations, the mechanical response of the bulk superconductor is determined. During the PFM process, the change in temperature has a dramatic effect on the radial and hoop stresses, and the maximum radial and hoop stress are 24.2 {{MPa}} and 22.6 {{MPa}}, respectively. The mechanical responses of a superconductor for different cases are also studied, such as the peak value of the applied field and the size of bulk superconductors. Finally, the stresses are also presented for different magnetization methods.

  5. Stress Evaluation while Prolonged Driving Operation Using the Facial Skin Temperature

    NASA Astrophysics Data System (ADS)

    Asano, Hirotoshi; Muto, Takumi; Ide, Hideto

    There is a relation to the accident of a car and the physiological and psychological state of a driver. The stress may lead to the fall of a fatigue or attentiveness. Therefore, it is an important subject from viewpoint such as accident prevention to evaluate the mental state of a driver. The study aimed at the development of a quantitative instrumentation technology of the stress when a subject is driving for a long time. First of all, we measured the physiological and psychological stress of a driver. The facial skin temperature and ventricular rate that was driver's physiological amount were measured and compared it with visual analog scale of the subjective amount. It was able to be obtaining of the high correlation in facial skin temperature and visual analog scale from the outcome of the experiment. Therefore, the possibility of appreciable of driver's stress at a facial skin temperature was shown. As a result of the experiment, we showed a possibility that facial skin temperature could evaluate long driving stress.

  6. Acute and long-term behavioral correlates of underwater trauma--potential relevance to stress and post-stress syndromes.

    PubMed

    Richter-Levin, G

    1998-06-02

    As a consequence of a brief but significantly extreme stressor, an individual will experience a stress response, which may sometimes develop into Acute Stress Disorder (ASD) or Post-Traumatic Stress Disorder (PTSD). Though a rat model for ASD and PTSD is not expected to encompass the richness and complexity of the disorders in humans, it will enable the study of the common underlying mechanisms that generate the disorders, the study of pre-trauma etiological aspects of the disorders and the screening of drugs with potential relevance to the treatment of the disorders. One well-documented aspect of PTSD is the enhancing influence of contextual elements on the appearance of symptoms of the post-stress trauma. To exploit this effect, we have chosen to assess the effects of an underwater trauma in the Morris water maze since the effects of such trauma on memory and attention can be later evaluated in the context of the trauma. At both 1 h and 3 weeks after the trauma, significant behavioral deficits were observed in the water maze. The effects of the underwater trauma on the performance of rats in the water maze were context specific. Underwater trauma in a different (out-of-context) water container had no effects on the ability of rats to perform a spatial memory task in the water maze. An elevated level of anxiety was found in the plus maze test, independently of whether the trauma was performed in the water maze or in a different (out-of-context) water container. The results indicate that a within-context underwater trauma has both acute and lasting behavioral consequences which can be assessed using a spatial memory test in the context of the trauma. The results are discussed in relation to their relevance to stress and PTSD.

  7. Simulating canopy temperature for modelling heat stress in cereals

    USDA-ARS?s Scientific Manuscript database

    Crop models must be improved to account for the large effects of heat stress effects on crop yields. To date, most approaches in crop models use air temperature despite evidence that crop canopy temperature better explains yield reductions associated with high temperature events. This study presents...

  8. Acute psychological stress increases plasma levels of cortisol, prolactin and TSH.

    PubMed

    Schedlowski, M; Wiechert, D; Wagner, T O; Tewes, U

    1992-01-01

    The effects of acute stress during a parachute jump on hormonal responses were studied in 12 experienced and 11 inexperienced military parachutists. Each subject performed two jumps. Prior to and immediately after each jump blood samples were drawn and analysed for plasma levels of cortisol, prolactin, thyrotropin (TSH), somatotropin (STH), and luteinizing hormone (LH). While there was a significant increase in cortisol, prolactin and TSH levels after both jumps, no alterations could be observed in STH and LH levels. Stress-induced hormonal responses were not affected by jump experience. There was also no association between the endocrine variables and anxiety scores.

  9. A single session of hatha yoga improves stress reactivity and recovery after an acute psychological stress task-A counterbalanced, randomized-crossover trial in healthy individuals.

    PubMed

    Benvenutti, Mateus J; Alves, Eduardo da Sliva; Michael, Scott; Ding, Ding; Stamatakis, Emmanuel; Edwards, Kate M

    2017-12-01

    Yoga is promoted as an anti-stress activity, however, little is known about the mechanisms through which it acts. The present study investigated the acute effects of a hatha yoga session, displayed on a video, on the response to and recovery from an acute psychological stressor. Twenty-four healthy young adults took part in a counterbalanced, randomized-crossover trial, with a yoga and a control condition (watching TV). Participants attended the laboratory in the afternoon on two days and each session comprised a baseline, control or yoga task, stress task and recovery. Blood pressure (BP), heart rate (HR) and salivary cortisol responses were measured. State cognitive- and somatic-anxiety along with self-confidence were assessed before and after the stressor. Although no difference in the BP or HR responses to stress were found between conditions, systolic BP (p=0.047) and diastolic BP (p=0.018) recovery from stress were significantly accelerated and salivary cortisol reactivity was significantly lower (p=0.01) in the yoga condition. A yoga session also increased self-confidence (p=0.006) in preparation for the task and after completion. Moreover, self-confidence reported after the stress task was considered debilitative towards performance in the control condition, but remained facilitative in the yoga condition. Our results show that a single video-instructed session of hatha yoga was able to improve stress reactivity and recovery from an acute stress task in healthy individuals. These positive preliminary findings encourage further investigation in at-risk populations in which the magnitude of effects may be greater, and support the use of yoga for stress reactivity and recovery. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Sex differences and the role of acute stress in the open-field tower maze.

    PubMed

    Lipatova, Olga; Campolattaro, Matthew M; Dixon, Dawndra C; Durak, Ayse

    2018-05-15

    Many studies provide evidence that differences in spatial learning exist between males and females. However, it is necessary to consider non-mnemonic factors that may influence these findings. The present experiment investigated acquisition, retention, and the effects of stress on response- and place-learning in male and female rats. Rats were trained in an open-field tower maze. Procedures were used to minimize stress in the rats, and their ability to solve place- or response-learning in the maze was determined by analyzing a response variable (i.e., first choice correct response) that was not influenced by general locomotor activity. The results revealed that male and female rats acquire place- and response-learning at the same rate even though females moved significantly faster in the maze. However, females showed better retrieval of place-, but not response-learning compared to male rats. This effect appeared to be enhanced when the rats were tested immediately following an acute restraint stress. Furthermore, both female and male rats that were exposed to acute restraint stress showed less impairment than controls when subsequently tested in a novel situation. These findings have clinical implications that a mild physiological stress response can make one more cognitively resistant to adversities later in life. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Acute post-traumatic stress symptoms and age predict outcome in military blast concussion.

    PubMed

    Mac Donald, Christine L; Adam, Octavian R; Johnson, Ann M; Nelson, Elliot C; Werner, Nicole J; Rivet, Dennis J; Brody, David L

    2015-05-01

    High rates of adverse outcomes have been reported following blast-related concussive traumatic brain injury in US military personnel, but the extent to which such adverse outcomes can be predicted acutely after injury is unknown. We performed a prospective, observational study of US military personnel with blast-related concussive traumatic brain injury (n = 38) and controls (n = 34) enrolled between March and September 2012. Importantly all subjects returned to duty and did not require evacuation. Subjects were evaluated acutely 0-7 days after injury at two sites in Afghanistan and again 6-12 months later in the United States. Acute assessments revealed heightened post-concussive, post-traumatic stress, and depressive symptoms along with worse cognitive performance in subjects with traumatic brain injury. At 6-12 months follow-up, 63% of subjects with traumatic brain injury and 20% of controls had moderate overall disability. Subjects with traumatic brain injury showed more severe neurobehavioural, post-traumatic stress and depression symptoms along with more frequent cognitive performance deficits and more substantial headache impairment than control subjects. Logistic regression modelling using only acute measures identified that a diagnosis of traumatic brain injury, older age, and more severe post-traumatic stress symptoms provided a good prediction of later adverse global outcomes (area under the receiver-operating characteristic curve = 0.84). Thus, US military personnel with concussive blast-related traumatic brain injury in Afghanistan who returned to duty still fared quite poorly on many clinical outcome measures 6-12 months after injury. Poor global outcome seems to be largely driven by psychological health measures, age, and traumatic brain injury status. The effects of early interventions and longer term implications of these findings are unknown. © The Author (2015). Published by Oxford University Press on behalf of the Guarantors of Brain. All

  12. Baicalin ameliorates isoproterenol-induced acute myocardial infarction through iNOS, inflammation and oxidative stress in rat

    PubMed Central

    Chen, Huaguo; Xu, Yongfu; Wang, Jianzhong; Zhao, Wei; Ruan, Huihui

    2015-01-01

    Baicalin belongs to glucuronic acid glycosides and after hydrolysisbaicalein and glucuronic acid come into being. It has such effects as clearing heat and removing toxicity, anti-inflammation, choleresis, bringing high blood pressure down, diuresis, anti-allergic reaction and so on. In this study, we investigated whether baicalin ameliorates isoproterenol-induced acute myocardial infarction and its mechanism. Rat model of acute myocardial infarction was induced by isoproterenol. Casein kinase (CK), the MB isoenzyme of creatine kinase (CK-MB), lactate dehydrogenase (LDH), cardiac troponin T (cTnT) and infarct size measurement were used to measure the protective effect of baicalin on isoproterenol-induced acute myocardial infarction. iNOS protein expression in rat was analyzed using western blot analysis. Tumor necrosis factor-alpha (TNF-α), interleukin 6 (IL-6), malondialdehyde (MDA) and superoxide dismutase (SOD) and caspase-3 activation levels were explored using commercial ELISA kits. In the acute myocardial infarction experiment, baicalin effectively ameliorates the level of CK, CK-MB, LDH and cTnT, reduced infarct size in acute myocardial infarction rat model. Meanwhile, treatment with baicalin effectively decreased the iNOS protein expression, inflammatory factors and oxidative stresses in a rat model of acute myocardial infarction. However, baicalin emerged that anti-apoptosis activity and suppressed the activation of caspase-3 in a rat model of acute myocardial infarction. The data suggest that the protective effect of baicalin ameliorates isoproterenol-induced acute myocardial infarction through iNOS, inflammation and oxidative stress in rat. PMID:26617721

  13. Cardiovascular reactivity to acute psychological stress following sleep deprivation.

    PubMed

    Franzen, Peter L; Gianaros, Peter J; Marsland, Anna L; Hall, Martica H; Siegle, Greg J; Dahl, Ronald E; Buysse, Daniel J

    2011-10-01

    Psychological stress and sleep disturbances are highly prevalent and are both implicated in the etiology of cardiovascular diseases. Given the common co-occurrence of psychological distress and sleep disturbances including short sleep duration, this study examined the combined effects of these two factors on blood pressure reactivity to immediate mental challenge tasks after well-rested and sleep-deprived experimental conditions. Participants (n = 20) were healthy young adults free from current or past sleep, psychiatric, or major medical disorders. Using a within-subjects crossover design, we examined acute stress reactivity under two experimental conditions: after a night of normal sleep in the laboratory and after a night of total sleep deprivation. Two standardized psychological stress tasks were administered, a Stroop color-word naming interference task and a speech task, which were preceded by a prestress baseline period and followed by a poststress recovery period. Each period was 10 minutes in duration, and blood pressure recordings were collected every 2.5 minutes throughout each period. Mean blood pressure responses during stress and recovery periods were examined with a mixed-effects analysis of covariance, controlling for baseline blood pressure. There was a significant interaction between sleep deprivation and stress on systolic blood pressure (F(2,82.7) = 4.05, p = .02). Systolic blood pressure was higher in the sleep deprivation condition compared with the normal sleep condition during the speech task and during the two baseline periods. Sleep deprivation amplified systolic blood pressure increases to psychological stress. Sleep loss may increase cardiovascular risk by dysregulating stress physiology.

  14. Influence of acute stress on spatial tasks in humans.

    PubMed

    Richardson, Anthony E; VanderKaay Tomasulo, Melissa M

    2011-07-06

    Few studies have investigated the relationship between stress and spatial performance in humans. In this study, participants were exposed to an acute laboratory stressor (Star Mirror Tracing Task) or a control condition (watching a nature video) and then performed two spatial tasks. In the first task, participants navigated through a virtual reality (VR) environment and then returned to the environment to make directional judgments relating to the learned targets. In the second task, perspective taking, participants made directional judgments to targets after imagined body rotations with respect to a map. Compared to the control condition, participants in the Stress condition showed increases in heart rate and systolic and diastolic blood pressure indicating sympathetic adrenal medulla (SAM) axis activation. Participants in the Stress condition also reported being more anxious, angry, frustrated, and irritated than participants in the Non-Stress condition. Salivary cortisol did not differ between conditions, indicating no significant hypothalamic-pituitary-adrenocortical (HPA) axis involvement. In the VR task, memory encoding was unaffected as directional error was similar in both conditions; however, participants in the Stress condition responded more slowly, which may be due to increases in negative affect, SAM disruption in spatial memory retrieval through catecholamine release, or a combination of both factors. In the perspective taking task, participants were also slower to respond after stress, suggesting interference in the ability to adopt new spatial orientations. Additionally, sex differences were observed in that men had greater accuracy on both spatial tasks, but no significant Sex by Stress condition interactions were demonstrated. Copyright © 2011 Elsevier Inc. All rights reserved.

  15. Delay discounting and response disinhibition under acute experimental stress in women with borderline personality disorder and adult attention deficit hyperactivity disorder.

    PubMed

    Krause-Utz, A; Cackowski, S; Daffner, S; Sobanski, Esther; Plichta, Michael M; Bohus, M; Ende, G; Schmahl, C

    2016-11-01

    Impulsivity is a core feature of borderline personality disorder (BPD) and attention deficit hyperactivity disorder (ADHD). In BPD, impulsive behavior primarily occurs under acute stress; impulse control deficits under non-stress conditions may be partly related to co-morbid ADHD. We aimed to investigate whether acute experimental stress has an impact on self-reported impulsivity, response inhibition (action withholding, action cancelation) and delay discounting in BPD compared to ADHD. Thirty female BPD patients, 28 female ADHD patients (excluding patients with co-morbid BPD and ADHD), and 30 female healthy controls (HC) completed self-reports and behavioral measures of impulsivity (IMT, assessing action withholding; GoStop, measuring action cancelation, Delay Discounting Task) under baseline conditions and after an experimental stress induction (Mannheim Multicomponent Stress Test). Both patient groups reported higher impulsivity than HC, ADHD reported higher trait impulsivity than BPD. On the IMT, ADHD showed significant action-withholding deficits under both conditions, while BPD performed significantly worse than HC under stress. In BPD but not ADHD and HC, action-withholding deficits (IMT) were significantly increased under stress compared to baseline, while no group/stress effects were found for action cancelation (GoStop). Delay discounting was significantly more pronounced in BPD than in HC (no stress effect was found). In BPD, behavioral deficits in action withholding (but not in action cancelation) appear to be influenced by acute experimental stress. Delay discounting seems to be a general feature of BPD, independent of co-morbid ADHD and acute stress, possibly underlying typical expressions of behavioral impulsivity in the disorder.

  16. Increases in anxiety-like behavior induced by acute stress are reversed by ethanol in adolescent but not adult rats.

    PubMed

    Varlinskaya, Elena I; Spear, Linda P

    2012-01-01

    Repeated exposure to stressors has been found to increase anxiety-like behavior in laboratory rodents, with the social anxiety induced by repeated restraint being extremely sensitive to anxiolytic effects of ethanol in both adolescent and adult rats. No studies, however, have compared social anxiogenic effects of acute stress or the capacity of ethanol to reverse this anxiety in adolescent and adult animals. Therefore, the present study was designed to investigate whether adolescent [postnatal day (P35)] Sprague-Dawley rats differ from their adult counterparts (P70) in the impact of acute restraint stress on social anxiety and in their sensitivity to the social anxiolytic effects of ethanol. Animals were restrained for 90 min, followed by examination of stress- and ethanol-induced (0, 0.25, 0.5, 0.75, and 1 g/kg) alterations in social behavior using a modified social interaction test in a familiar environment. Acute restraint stress increased anxiety, as indexed by reduced levels of social investigation at both ages, and decreased social preference among adolescents. These increases in anxiety were dramatically reversed among adolescents by acute ethanol. No anxiolytic-like effects of ethanol emerged following restraint stress in adults. The social suppression seen in response to higher doses of ethanol was reversed by restraint stress in animals of both ages. To the extent that these data are applicable to humans, the results of the present study provide some experimental evidence that stressful life events may increase the attractiveness of alcohol as an anxiolytic agent for adolescents. Copyright © 2011 Elsevier Inc. All rights reserved.

  17. Indication of attenuated DHEA-s response during acute psychosocial stress in patients with clinical burnout.

    PubMed

    Lennartsson, Anna-Karin; Sjörs, Anna; Jonsdottir, Ingibjörg H

    2015-08-01

    Dehydroepiandrosterone sulphate (DHEA-s) is an anabolic protective hormone. We have previously reported that DHEA-s production capacity is attenuated in stressed individuals. The aim of the present study was to investigate the DHEA-s response during acute psychosocial stress in patients with clinical burnout. Seventeen patients with clinical burnout were compared to 13 non-chronically stressed healthy controls, aged 31-50 years (mean age 41 years, SD 6 years), as they underwent the Trier Social Stress Test (TSST). All patients fulfilled diagnostic criteria for stress-related exhaustion disorder, which is a criteria-based diagnosis that has been used in Sweden since 2005 to define patients seeking health-care for clinical burnout. Blood samples were collected before, directly after the stress test, and after 30 min of recovery. DHEA-s levels were measured and delta values (peak levels minus baseline levels) plus area under the curve with respect to increase (AUCI) were calculated. The patients had 43% smaller AUCI DHEA-s (p=0.041) during the stress test. The delta DHEA-s was 34% lower in the patients, however, this difference was not statistically significant (p=0.054). The study indicates that DHEA-s production capacity during acute stress may be attenuated in patients with clinical burnout. Reduced DHEA-s production may constitute one of the links between stress, burnout and the associated adverse health. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. Differential effects of 5-HTTLPR genotypes on mood, memory, and attention bias following acute tryptophan depletion and stress exposure.

    PubMed

    Firk, Christine; Markus, C Rob

    2009-05-01

    Polymorphisms of the serotonin transporter gene (5-HTTLPR) may be associated with increased vulnerability to acute tryptophan depletion (ATD) and depression vulnerability especially following stressful life events. The aim of the present study was to investigate the effects of ATD in subjects with different 5-HTTLPR profiles before and after stress exposure on affective and cognitive-attentional changes. Eighteen subjects with homozygotic short alleles (S'/S') and 17 subjects with homozygotic long alleles (L'/L') of the 5-HTTLPR participated in a double-blind, placebo-controlled, crossover design to measure the effects of ATD on mood, memory, and attention before and after acute stress exposure. ATD lowered mood in all subjects independent of genotype. In S'/S' genotypes, mild acute stress increased depressive mood and in L'/L' genotypes increased feelings of vigor. Furthermore, S'/S' genotypes differed from L'/L' genotypes on measures of attention independent of treatment and memory following ATD. Polymorphisms of the 5-HTTLPR differentially affect responses to mild stress and ATD, suggesting greater vulnerability of S'/S' carriers to serotonergic manipulations and supporting increased depression vulnerability.

  19. An exploratory study of the association of acute posttraumatic stress, depression, and pain to cognitive functioning in mild traumatic brain injury.

    PubMed

    Massey, Jessica S; Meares, Susanne; Batchelor, Jennifer; Bryant, Richard A

    2015-07-01

    Few studies have examined whether psychological distress and pain affect cognitive functioning in the acute to subacute phase (up to 30 days postinjury) following mild traumatic brain injury (mTBI). The current study explored whether acute posttraumatic stress, depression, and pain were associated with performance on a task of selective and sustained attention completed under conditions of increasing cognitive demands (standard, auditory distraction, and dual-task), and on tests of working memory, memory, processing speed, reaction time (RT), and verbal fluency. At a mean of 2.87 days (SD = 2.32) postinjury, 50 adult mTBI participants, consecutive admissions to a Level 1 trauma hospital, completed neuropsychological tests and self-report measures of acute posttraumatic stress, depression, and pain. A series of canonical correlation analyses was used to explore the relationships of a common set of psychological variables to various sets of neuropsychological variables. Significant results were found on the task of selective and sustained attention. Strong relationships were found between psychological variables and speed (r(c) = .56, p = .02) and psychological variables and accuracy (r(c) = .68, p = .002). Pain and acute posttraumatic stress were associated with higher speed scores (reflecting more correctly marked targets) under standard conditions. Acute posttraumatic stress was associated with lower accuracy scores across all task conditions. Moderate but nonsignificant associations were found between psychological variables and most cognitive tasks. Acute posttraumatic stress and pain show strong associations with selective and sustained attention following mTBI. (c) 2015 APA, all rights reserved).

  20. Certification testing as an acute naturalistic stressor for disaster dog handlers.

    PubMed

    Lit, L; Boehm, D; Marzke, S; Schweitzer, J; Oberbauer, A M

    2010-09-01

    USA Federal Disaster Canine Teams, consisting of a handler and a dog, are essential for locating survivors following a disaster. Certification, required by the Federal Emergency Management Agency Urban Search and Rescue organization, requires two successful mock searches. Confirmation of the certification testing process as an acute stressor might offer further opportunities to consider stress effects on handlers and dogs in a controlled environment. This study used a pretest-posttest design to evaluate relationships between salivary hormone concentrations (cortisol and testosterone) and subjective stress ratings in handlers and controls, handler assessments of stress in their dogs, and posttest temperature and pulse rate in dogs. Posttest, both subjective stress ratings and salivary cortisol concentration were higher in handlers than controls with both correlated to handlers' assessment of stress in their dogs. Handlers' posttest salivary cortisol concentration was associated with posttest dog pulse and temperature. Posttest cortisol concentration was lower in handlers who were successfully certified compared with those who failed, and was also lower in handlers whose primary occupation was "firefighter". Salivary testosterone concentrations increased from pretest to posttest in handlers but decreased in controls, and higher posttest handler testosterone concentration was negatively associated with posttest dog pulse rate. These findings confirm certification testing as an acute stressor, suggest a relationship between stress and performance moderated by occupation, and demonstrate an interaction between handler stress and dog physiological responses. This certification testing offers a controlled environment for targeted evaluation of effects of an acute naturalistic stressor on disaster dog handlers and dogs.

  1. Overexpression of monoubiquitin improves photosynthesis in transgenic tobacco plants following high temperature stress.

    PubMed

    Tian, Fengxia; Gong, Jiangfeng; Zhang, Jin; Feng, Yanan; Wang, Guokun; Guo, Qifang; Wang, Wei

    2014-09-01

    The ubiquitin/26S proteasome system (Ub/26S) is implicated in abiotic stress responses in plants. In this paper, transgenic tobacco plants overexpressing Ta-Ub2 from wheat were used to study the functions of Ub in the improvement of photosynthesis under high temperature (45°C) stress. We observed higher levels of Ub conjugates in transgenic plants under high temperature stress conditions compared to wild type (WT) as a result of the constitutive overexpression of Ta-Ub2, suggesting increased protein degradation by the 26S proteasome system under high temperature stress. Overexpressing Ub increased the photosynthetic rate (Pn) of transgenic tobacco plants, consistent with the improved ATPase activity in the thylakoid membrane and enhanced efficiency of PSII photochemistry. The higher D1 protein levels following high temperature stress in transgenic plants than WT were also observed. These findings imply that Ub may be involved in tolerance of photosynthesis to high temperature stress in plants. Compared with WT, the transgenic plants showed lower protein carbonylation and malondialdehyde (MDA) levels, less reactive oxygen species (ROS) accumulation, but higher antioxidant enzyme activity under high temperature stress. These findings suggest that the improved antioxidant capacity of transgenic plants may be one of the most important mechanisms underlying Ub-regulated high temperature tolerance. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  2. Pasireotide treatment does not modify hyperglycemic and corticosterone acute restraint stress responses in rats.

    PubMed

    Ribeiro-Oliveira, Antônio; Schweizer, Junia R O L; Amaral, Pedro H S; Bizzi, Mariana F; Silveira, Warley Cezar da; Espirito-Santo, Daniel T A; Zille, Giancarlo; Soares, Beatriz S; Schmid, Herbert A; Yuen, Kevin C J

    2018-04-17

    Pasireotide is a new-generation somatostatin analog that acts through binding to multiple somatostatin receptor subtypes. Studies have shown that pasireotide induces hyperglycemia, reduces glucocorticoid secretion, alters neurotransmission, and potentially affects stress responses typically manifested as hyperglycemia and increased corticosterone secretion. This study specifically aimed to evaluate whether pasireotide treatment modifies glucose and costicosterone secretion in response to acute restraint stress. Male Holtzman rats of 150-200 g were treated with pasireotide (10 µg/kg/day) twice-daily for two weeks or vehicle for the same period. Blood samples were collected at baseline and after 5, 10, 30, and 60 min of restraint stress. The three experimental groups comprised of vehicle + restraint (VEHR), pasireotide + restraint (PASR), and pasireotide + saline (PASNR). Following pasireotide treatment, no significant differences in baseline glucose and corticosterone levels were observed among the three groups. During restraint, hyperglycemia was observed at 10 min (p < .01 for both comparisons), peaked at 30 min (p < .01 for both comparisons) and showed higher 60 min areas under glucose curves in the VEHR and PASR stressed groups when compared to the non-stressed PASNR group (p < .05 for both comparisons). Restraint also increased corticosterone secretion in the VEHR and PASR stressed groups at 5 min (p < .01 for both comparisons), and peaked at 30 min (p < .01 for both comparisons) with corresponding higher 60 min areas under corticosterone curves when compared to the non-stressed PASNR group (p < .01 for both comparisons). In conclusion, pasireotide treatment does not modify hyperglycemic- and corticosterone-restraint stress responses, thus preserving acute stress regulation.

  3. AT1 and AT2 Receptors in the Prelimbic Cortex Modulate the Cardiovascular Response Evoked by Acute Exposure to Restraint Stress in Rats.

    PubMed

    Brasil, Taíz F S; Fassini, Aline; Corrêa, Fernando M

    2018-01-01

    The prelimbic cortex (PL) is an important structure in the neural pathway integrating stress responses. Brain angiotensin is involved in cardiovascular control and modulation of stress responses. Blockade of angiotensin receptors has been reported to reduce stress responses. Acute restraint stress (ARS) is a stress model, which evokes sustained blood pressure increase, tachycardia, and reduction in tail temperature. We therefore hypothesized that PL locally generated angiotensin and angiotensin receptors modulate stress autonomic responses. To test this hypothesis, we microinjected an angiotensin-converting enzyme (ACE) inhibitor or angiotensin antagonists into the PL, prior to ARS. Male Wistar rats were used; guide cannulas were bilaterally implanted in the PL for microinjection of vehicle or drugs. A polyethylene catheter was introduced into the femoral artery to record cardiovascular parameters. Tail temperature was measured using a thermal camera. ARS was started 10 min after PL treatment with drugs. Pretreatment with ACE inhibitor lisinopril (0.5 nmol/100 nL) reduced the pressor response, but did not affect ARS-evoked tachycardia. At a dose of 1 nmol/100 nL, it reduced both ARS pressor and tachycardic responses. Pretreatment with candesartan, AT1 receptor antagonist reduced ARS-evoked pressor response, but not tachycardia. Pretreatment with PD123177, AT2 receptor antagonist, reduced tachycardia, but did not affect ARS pressor response. No treatment affected ARS fall in tail temperature. Results suggest involvement of PL angiotensin in the mediation of ARS cardiovascular responses, with participation of both AT1 and AT2 receptors. In conclusion, results indicate that PL AT1-receptors modulate the ARS-evoked pressor response, while AT2-receptors modulate the tachycardic component of the autonomic response.

  4. Acute stress exposure preceding transient global brain ischemia exacerbates the decrease in cortical remodeling potential in the rat retrosplenial cortex.

    PubMed

    Kutsuna, Nobuo; Yamashita, Akiko; Eriguchi, Takashi; Oshima, Hideki; Suma, Takeshi; Sakatani, Kaoru; Yamamoto, Takamitsu; Yoshino, Atsuo; Katayama, Yoichi

    2014-01-01

    Doublecortin (DCX)-immunoreactive (-ir) cells are candidates that play key roles in adult cortical remodeling. We have previously reported that DCX-ir cells decrease after stress exposure or global brain ischemia (GBI) in the cingulate cortex (Cg) of rats. Herein, we investigate whether the decrease in DCX-ir cells is exacerbated after GBI due to acute stress exposure preconditioning. Twenty rats were divided into 3 groups: acute stress exposure before GBI (Group P), non-stress exposure before GBI (Group G), and controls (Group C). Acute stress or GBI was induced by a forced swim paradigm or by transient bilateral common carotid artery occlusion, respectively. DCX-ir cells were investigated in the anterior cingulate cortex (ACC) and retrosplenial cortex (RS). The number of DCX-ir cells per unit area (mm(2)) decreased after GBI with or without stress preconditioning in the ACC and in the RS (ANOVA followed by a Tukey-type test, P<0.001). Moreover, compared to Group G, the number in Group P decreased significantly in RS (P<0.05), though not significantly in ACC. Many of the DCX-ir cells were co-localized with the GABAergic neuronal marker parvalbumin. The present study indicates that cortical remodeling potential of GABAergic neurons of Cg decreases after GBI, and moreover, the ratio of the decrease is exacerbated by acute stress preconditioning in the RS. Copyright © 2013 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  5. Experiences of stress among nurses in acute mental health settings.

    PubMed

    Currid, Thomas

    To explore occupational stressors, the lived experience of stress and the meaning of this experience for staff working in acute mental health care. The study adopted a hermeneutic phenomenological approach to ascertain the lived experience of stress among eight qualified staff working in a mental health NHS trust in London. A semi-structured interview format was used. Interviews were transcribed verbatim and analysed using an interpretative phenomenological analysis framework. The occupational experience of nurses in this study indicates that staff are frequently subjected to violent and aggressive behaviour from patients. Such experiences adversely affect patient outcomes in that staff may be reluctant to engage with such individuals because of anxiety about being hurt or experiencing further intimidation. Environmental pressures coupled with high activity levels mean that staff have little time to focus on the task at hand or to plan future activities. As a result they find that when they go home they are unable to switch off from work. Further investment is needed in acute mental health settings and in staff who work in this area. If this does not happen, it is likely that the quality of service provision will deteriorate and nurses' health and wellbeing will suffer.

  6. Seawater inhalation induces acute lung injury via ROS generation and the endoplasmic reticulum stress pathway

    PubMed Central

    Li, Cong-Cong; Lu, Xi; Qian, Wei-Sheng; Li, Yu-Juan; Jin, Fa-Guang; Mu, De-Guang

    2018-01-01

    Seawater (SW) inhalation can induce acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). In the present study, SW induced apoptosis of rat alveolar epithelial cells and histopathological alterations to lung tissue. Furthermore, SW administration increased generation of reactive oxygen species (ROS), whereas pretreatment with the ROS scavenger, N-acetyl-L-cysteine (NAC), significantly decreased ROS generation, apoptosis and histopathological alterations. In addition, SW exposure upregulated the expression levels of glucose-regulated protein 78 (GRP78) and CCAAT/enhancer binding protein homologous protein (CHOP), which are critical proteins in the endoplasmic reticulum (ER) stress response, thus indicating that SW may activate ER stress. Conversely, blocking ER stress with 4-phenylbutyric acid (4-PBA) significantly improved SW-induced apoptosis and histopathological alterations, whereas an ER stress inducer, thapsigargin, had the opposite effect. Furthermore, blocking ROS with NAC inhibited SW-induced ER stress, as evidenced by the downregulation of GRP78, phosphorylated (p)-protein kinase R-like ER kinase (PERK), p-inositol-requiring kinase 1α (IRE1α), p-50 activating transcription factor 6α and CHOP. In addition, blocking ER stress with 4-PBA decreased ROS generation. In conclusion, the present study indicated that ROS and ER stress pathways, which are involved in alveolar epithelial cell apoptosis, are important in the pathogenesis of SW-induced ALI. PMID:29436612

  7. Effects of temperature distribution and elastic properties of materials on gas-turbine-disk stresses

    NASA Technical Reports Server (NTRS)

    Holms, Arthur G; Faldetta, Richard D

    1947-01-01

    Calculations were made to determine the influence of changes in temperature distribution and in elastic material properties on calculated elastic stresses for a typical gas-turbine disk. Severe temperature gradients caused thermal stresses of sufficient magnitude to reduce the operating safety of the disk. Small temperature gradients were found to be desirable because they produced thermal stresses that subtracted from the centrifugal stresses in the region of the rim. The thermal gradients produced a tendency for a severe stress condition to exist near the rim but this stress condition could be shifted away from the region of blade attachment by altering the temperature distribution. The investigation of elastic material properties showed that centrifugal stresses are slightly affected by changes in modulus of elasticity, but that thermal stresses are approximately proportional to modulus of elasticity and to coefficient of thermal expansion.

  8. Chronic and Acute Stress, Gender, and Serotonin Transporter Gene-Environment Interactions Predicting Depression Symptoms in Youth

    ERIC Educational Resources Information Center

    Hammen, Constance; Brennan, Patricia A.; Keenan-Miller, Danielle; Hazel, Nicholas A.; Najman, Jake M.

    2010-01-01

    Background: Many recent studies of serotonin transporter gene by environment effects predicting depression have used stress assessments with undefined or poor psychometric methods, possibly contributing to wide variation in findings. The present study attempted to distinguish between effects of acute and chronic stress to predict depressive…

  9. Body temperature measurement in mice during acute illness: implantable temperature transponder versus surface infrared thermometry.

    PubMed

    Mei, Jie; Riedel, Nico; Grittner, Ulrike; Endres, Matthias; Banneke, Stefanie; Emmrich, Julius Valentin

    2018-02-23

    Body temperature is a valuable parameter in determining the wellbeing of laboratory animals. However, using body temperature to refine humane endpoints during acute illness generally lacks comprehensiveness and exposes to inter-observer bias. Here we compared two methods to assess body temperature in mice, namely implanted radio frequency identification (RFID) temperature transponders (method 1) to non-contact infrared thermometry (method 2) in 435 mice for up to 7 days during normothermia and lipopolysaccharide (LPS) endotoxin-induced hypothermia. There was excellent agreement between core and surface temperature as determined by method 1 and 2, respectively, whereas the intra- and inter-subject variation was higher for method 2. Nevertheless, using machine learning algorithms to determine temperature-based endpoints both methods had excellent accuracy in predicting death as an outcome event. Therefore, less expensive and cumbersome non-contact infrared thermometry can serve as a reliable alternative for implantable transponder-based systems for hypothermic responses, although requiring standardization between experimenters.

  10. Systolic blood pressure reactivity during submaximal exercise and acute psychological stress in youth

    USDA-ARS?s Scientific Manuscript database

    Background: Studies in youth show an association between systolic blood-pressure (SBP) reactivity to acute psychological stress and carotid artery intima-media thickness (CIMT). However, it has not yet been determined whether SBP reactivity during submaximal exercise is also associated with CIMT i...

  11. Heart rate variability during acute psychosocial stress: A randomized cross-over trial of verbal and non-verbal laboratory stressors.

    PubMed

    Brugnera, Agostino; Zarbo, Cristina; Tarvainen, Mika P; Marchettini, Paolo; Adorni, Roberta; Compare, Angelo

    2018-05-01

    Acute psychosocial stress is typically investigated in laboratory settings using protocols with distinctive characteristics. For example, some tasks involve the action of speaking, which seems to alter Heart Rate Variability (HRV) through acute changes in respiration patterns. However, it is still unknown which task induces the strongest subjective and autonomic stress response. The present cross-over randomized trial sought to investigate the differences in perceived stress and in linear and non-linear analyses of HRV between three different verbal (Speech and Stroop) and non-verbal (Montreal Imaging Stress Task; MIST) stress tasks, in a sample of 60 healthy adults (51.7% females; mean age = 25.6 ± 3.83 years). Analyses were run controlling for respiration rates. Participants reported similar levels of perceived stress across the three tasks. However, MIST induced a stronger cardiovascular response than Speech and Stroop tasks, even after controlling for respiration rates. Finally, women reported higher levels of perceived stress and lower HRV both at rest and in response to acute psychosocial stressors, compared to men. Taken together, our results suggest the presence of gender-related differences during psychophysiological experiments on stress. They also suggest that verbal activity masked the vagal withdrawal through altered respiration patterns imposed by speaking. Therefore, our findings support the use of highly-standardized math task, such as MIST, as a valid and reliable alternative to verbal protocols during laboratory studies on stress. Copyright © 2018 Elsevier B.V. All rights reserved.

  12. Melatonin Supplementation Ameliorates Energy Charge and Oxidative Stress Induced by Acute Exercise in Rat Heart Tissue

    PubMed Central

    Cimen, Behzat; Uz, Ali; Cetin, Ihsan; Cimen, Leyla; Cetin, Aysun

    2017-01-01

    Background Regular physical exercises may help people to be more resistant to everyday problems; however, how acute and intense exercises affect the heart tissues functioning with maximum capacity and how melatonin changes the effect of acute and intense exercises are still not obvious. We aimed to comprehend whether melatonin intravenous injection supports the oxidative/antioxidative conditions and energy charge in heart tissues of rats exposed to acute swimming exercise. Methods Thirty Wistar-albino male rats were categorized into 3 groups with equal number of subjects. Control group performed no application, and acute intensive swimming exercise group were subjected to acute intensive swimming exercise for 30 minutes, and melatonin group were applied 25 mg/kg single dose melatonin administration prior to 30 minutes acute intensive swimming exercise. The levels of malondialdehyde (MDA), and superoxide dismutase, catalase and glutathione peroxidase activities were measured by spectrophotometric method; and the levels of 3-nitrotyrosine (3-NT) and energy charge were determined by a high performance liquid chromatography. Results Tissue MDA and 3-NT levels of the acute intensive exercise group were found to be higher than the control group. It was also found that the melatonin administration increased the energy charge and antioxidant activities, while decreased tissue MDA and 3-NT levels in heart tissues. Our results provide evidence for melatonin that can exert potent protective effects on oxidative stress and energy charge for heart tissues in acute swimming exercise. Conclusions These findings suggest that the direct beneficial effects of melatonin could be potentially applied on prevention of oxidative stress and energy deficit. PMID:28959107

  13. Effect of temperature in multiple biomarkers of oxidative stress in coastal shrimp.

    PubMed

    Vinagre, Catarina; Madeira, Diana; Mendonça, Vanessa; Dias, Marta; Roma, Joma; Diniz, Mário S

    2014-04-01

    Various studies in captivity and in the wild have pointed to the effect of season, and temperature in particular, in the levels of the oxidative stress biomarkers currently used for environmental quality assessment. However, knowledge on how temperature affects the oxidative stress response is unavailable for most species. This study investigated the effect of increasing temperature on lipid peroxidation, catalase activity, superoxide dismutase and glutathione-S-transferase in the shrimps, Palaemon elegans and Palaemon serratus. It was concluded that increasing temperatures significantly affect all the biomarkers tested in both species, with the exception of superoxide dismutase in P. serratus which was not affected by temperature. The oxidative stress response was more intense in P. elegans, than in P. serratus, producing higher peaks of all biomarkers at temperatures between 22°C and 26°C, followed by low levels at higher temperatures. It was concluded that monitoring of ecosystems using oxidative stress biomarkers should take into account the species and thermal history of the organisms. Sampling should be avoided during heat waves and immediately after heat waves. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. A stress MRI of the shoulder for evaluation of ligamentous stabilizers in acute and chronic acromioclavicular joint instabilities.

    PubMed

    Izadpanah, Kaywan; Winterer, Jan; Vicari, Marco; Jaeger, Martin; Maier, Dirk; Eisebraun, Leonie; Ute Will, Jutta; Kotter, Elmar; Langer, Mathias; Südkamp, Norbert P; Hennig, Jürgen; Weigel, Mathias

    2013-06-01

    To show the feasibility of a stress magnetic resonance imaging (MRI) as a new method for simultaneous evaluation of the morphology and the functional integrity of the acromioclavicular joint (ACJ) ligamentous stabilizers. MRI of four volunteers, 10 patients with acute, and six with chronic ACJ injuries was performed using a 0.25 T open MRI scanner. A 2D-proton-density and a 3D-gradient-echo sequence at rest and under 6.5 kg shoulder traction were performed. Comparative measurements of the coracoclavicular and the acromioclavicular distance were performed. Additionally, the conoid and trapezoid ligament lengths were measured with multiplanar reconstructions. MRI at rest correctly identified tears of the coracoclavicular and the acromioclavicular ligaments in eight patients suffering acute ACJ injuries. Stress application helped to distinguish between partial and complete coracoclavicular ligament tears in two cases. Insufficiency of the ACJ ligaments was present in all acute and chronic ACJ injuries. Stress application in chronic ACJ ligaments revealed isolated insufficiency of the conoid ligament in three cases and of the trapezoid ligament in one case. Combined insufficiency was present in two cases. Stress MRI facilitates simultaneous acquisition of morphologic and functional information of the ACJ stabilizers. In acute ACJ injuries it helps to distinguish between partial and complete ligament tears. In chronic ACJ injuries it provides functional information of the ligament regrinds. Copyright © 2012 Wiley Periodicals, Inc.

  15. Effects of intravenous tryptophan infusion on thermoregulation in steers exposed to acute heat stress.

    PubMed

    Sutoh, Madoka; Kasuya, Etsuko; Yayou, Ken-Ichi

    2018-05-01

    This study was conducted to investigate the effect of tryptophan (TRP) supply on the thermoregulatory responses via brain serotonin (5-HT) in cattle. In period 1, 12 Holstein steers were kept under a constant room temperature (22°C) and were administered the intravenous (i.v.) infusion of saline or TRP (38.5 mg/kg/2 h). Changes in rectal temperature (RT), 5-HT concentration in the cerebrospinal fluid (CSF), and other factors involved in thermoregulation were measured. In period 2, the steers received the same treatments as in period 1; however, the room temperature was elevated from 22°C to 33°C during i.v. infusion and maintained at 33°C for 3 h. 5-HT concentration in CSF increased following TRP infusion in both periods, and RT significantly decreased following TRP infusion only in period 2. The effect of TRP on respiration rate and plasma prolactin and total triiodothyronine concentrations was not significant. These results suggest that increase in TRP supply can attenuate increase in RT in response to acute heat stress through the increase in brain 5-HT, followed by presumable increase in evaporative heat loss from the skin surface in cattle. It is possible that the increase in peripheral blood TRP metabolites could also participate in the hypothermic effect of TRP. © 2018 Japanese Society of Animal Science.

  16. Sleep quality but not sleep quantity effects on cortisol responses to acute psychosocial stress.

    PubMed

    Bassett, Sarah M; Lupis, Sarah B; Gianferante, Danielle; Rohleder, Nicolas; Wolf, Jutta M

    2015-01-01

    Given the well-documented deleterious health effects, poor sleep has become a serious public health concern and increasing efforts are directed toward understanding underlying pathways. One potential mechanism may be stress and its biological correlates; however, studies investigating the effects of poor sleep on a body's capacity to deal with challenges are lacking. The current study thus aimed at testing the effects of sleep quality and quantity on cortisol responses to acute psychosocial stress. A total of 73 college-aged adults (44 females) were investigated. Self-reported sleep behavior was assessed via the Pittsburgh Sleep Quality Index and salivary cortisol responses to the Trier Social Stress Test were measured. In terms of sleep quality, we found a significant three-way interaction, such that relative to bad sleep quality, men who reported fairly good or very good sleep quality showed blunted or exaggerated cortisol responses, respectively, while women's stress responses were less dependent on their self-reported sleep quality. Contrarily, average sleep duration did not appear to impact cortisol stress responses. Lastly, participants who reported daytime dysfunctions (i.e. having trouble staying awake or keeping up enthusiasm) also showed a trend to blunted cortisol stress responses compared to participants who did not experience these types of daytime dysfunctions. Overall, the current study suggests gender-specific stress reactivity dysfunctions as one mechanism linking poor sleep with detrimental physical health outcomes. Furthermore, the observed differential sleep effects may indicate that while the body may be unable to maintain normal hypothalamic-pituitary-adrenal functioning in an acute psychosocial stress situation after falling prey to low sleep quality, it may retain capacities to deal with challenges during extended times of sleep deprivation.

  17. Effect of acute heat stress and slaughter processing on poultry meat quality and postmortem carbohydrate metabolism.

    PubMed

    Wang, R H; Liang, R R; Lin, H; Zhu, L X; Zhang, Y M; Mao, Y W; Dong, P C; Niu, L B; Zhang, M H; Luo, X

    2017-03-01

    This study investigated the effects of acute heat stress and slaughter processing on poultry meat quality and carbohydrate metabolism. Broilers (200) were randomly divided into 2 groups receiving heat stress (HS; 36°C for one h), compared to a non-stressed control (C). At slaughter, each group was further divided into 2 groups for slaughter processing (L = laboratory; F = commercial factory). L group breasts were removed immediately after bleeding without carcass scalding or defeathering, and stored at 4°C. F group broilers were scalded (60°C, 45 s) after bleeding and defeathering. Then the breasts were removed and cooled in ice water until the core temperature was ≤4°C. Rates of Pectoralis core temperature and pH decline were changed by slaughter processing, but only HS affected ultimate pH in group L. HS muscles had higher L* values (P < 0.05) than controls at 24 h postmortem. Laboratory processing "hot-deboning" increased drip loss, which resulted in a lower cooked loss (P < 0.05). Postmortem glycolysis was affected only by HS. The speed of lactic acid accumulation and glycogen degradation was faster in the HS group than controls at 5 min postmortem. During storage the glycolysis rates were not different (P > 0.05). Sarcoplasmic protein solubility was higher in F processed birds (P < 0.05). HS decreased the solubility of myofibrillar and total protein in the L-slaughtered birds. Thus, HS caused a higher frequency of accelerated muscle glycolysis than controls. Factory processing (chilling) could not completely eliminate the effects of accelerated glycolysis caused by pre-slaughter HS. © 2016 Poultry Science Association Inc.

  18. Acute effects of heroin on negative emotional processing: relation of amygdala activity and stress-related responses.

    PubMed

    Schmidt, André; Borgwardt, Stefan; Gerber, Hana; Wiesbeck, Gerhard A; Schmid, Otto; Riecher-Rössler, Anita; Smieskova, Renata; Lang, Undine E; Walter, Marc

    2014-08-15

    Negative emotional states and abnormal stress reactivity are central components in drug addiction. The brain stress system in the amygdala is thought to play a key role in the maintenance of drug dependence through negative reinforcement. Although acute heroin administration was found to reduce anxiety, craving, and stress hormone release, whether these effects are reflected in amygdala activity has not yet been investigated. With a randomized, crossover, double-blind design, saline and heroin were administered to 22 heroin-dependent patients, whereas 17 healthy control subjects were included for the placebo administration only. We used functional magnetic resonance imaging to investigate blood oxygen level-dependent responses during fearful faces processing. Stress reactivity was measured by adrenocorticotropic hormone levels and by cortisol concentrations in serum and saliva 60 min after substance administration. Anxiety and craving levels were assessed with self-report ratings. Heroin administration acutely reduced the left amygdala response to fearful faces relative to the saline injection. Patients receiving saline showed a significantly higher left amygdala response to fearful faces than healthy control subjects, whose activity did not differ from patients receiving heroin. The left amygdala activity correlated significantly with scores on state-anxiety and levels of adrenocorticotropic hormone, serum cortisol, and saliva cortisol among all patients and control subjects. Our results show a direct relation between the acute heroin effects on stress-related emotions, stress reactivity, and left amygdala response to negative facial expressions. These findings provide new insights into the mechanisms underlying negative reinforcement in heroin addiction and the effects of regular heroin substitution. © 2013 Society of Biological Psychiatry Published by Society of Biological Psychiatry All rights reserved.

  19. Severe oxidative stress in an acute inflammatory demyelinating model in the rhesus monkey.

    PubMed

    Dunham, Jordon; van de Vis, Reinofke; Bauer, Jan; Wubben, Jacqueline; van Driel, Nikki; Laman, Jon D; 't Hart, Bert A; Kap, Yolanda S

    2017-01-01

    Oxidative stress is increasingly implicated as a co-factor of tissue injury in inflammatory/demyelinating disorders of the central nervous system (CNS), such as multiple sclerosis (MS). While rodent experimental autoimmune encephalomyelitis (EAE) models diverge from human demyelinating disorders with respect to limited oxidative injury, we observed that in a non-human primate (NHP) model for MS, namely EAE in the common marmoset, key pathological features of the disease were recapitulated, including oxidative tissue injury. Here, we investigated the presence of oxidative injury in another NHP EAE model, i.e. in rhesus macaques, which yields an acute demyelinating disease, which may more closely resemble acute disseminated encephalomyelitis (ADEM) than MS. Rhesus monkey EAE diverges from marmoset EAE by abundant neutrophil recruitment into the CNS and destructive injury to white matter. This difference prompted us to investigate to which extent the oxidative pathway features elicited in MS and marmoset EAE are reflected in the acute rhesus monkey EAE model. The rhesus EAE brain was characterized by widespread demyelination and active lesions containing numerous phagocytic cells and to a lesser extent T cells. We observed induction of the oxidative stress pathway, including injury, with a predilection of p22phox expression in neutrophils and macrophages/microglia. In addition, changes in iron were observed. These results indicate that pathogenic mechanisms in the rhesus EAE model may differ from the marmoset EAE and MS brain due to the neutrophil involvement, but may in the end lead to similar induction of oxidative stress and injury.

  20. The stress-buffering effect of acute exercise: Evidence for HPA axis negative feedback.

    PubMed

    Zschucke, Elisabeth; Renneberg, Babette; Dimeo, Fernando; Wüstenberg, Torsten; Ströhle, Andreas

    2015-01-01

    According to the cross-stressor adaptation hypothesis, physically trained individuals show lower physiological and psychological responses to stressors other than exercise, e.g. psychosocial stress. Reduced stress reactivity may constitute a mechanism of action for the beneficial effects of exercise in maintaining mental health. With regard to neural and psychoneuroendocrine stress responses, the acute stress-buffering effects of exercise have not been investigated yet. A sample of highly trained (HT) and sedentary (SED) young men was randomized to either exercise on a treadmill at moderate intensity (60-70% VO2max; AER) for 30 min, or to perform 30 min of "placebo" exercise (PLAC). 90 min later, an fMRI experiment was conducted using an adapted version of the Montreal Imaging Stress Task (MIST). The subjective and psychoneuroendocrine (cortisol and α-amylase) changes induced by the exercise intervention and the MIST were assessed, as well as neural activations during the MIST. Finally, associations between the different stress responses were analysed. Participants of the AER group showed a significantly reduced cortisol response to the MIST, which was inversely related to the previous exercise-induced α-amylase and cortisol fluctuations. With regard to the sustained BOLD signal, we found higher bilateral hippocampus (Hipp) activity and lower prefrontal cortex (PFC) activity in the AER group. Participants with a higher aerobic fitness showed lower cortisol responses to the MIST. As the Hipp and PFC are brain structures prominently involved in the regulation of the hypothalamus-pituitary-adrenal (HPA) axis, these findings indicate that the acute stress-buffering effect of exercise relies on negative feedback mechanisms. Positive affective changes after exercise appear as important moderators largely accounting for the effects related to physical fitness. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Stress Induced Cardiomyopathy Triggered by Acute Myocardial Infarction: A Case Series Challenging the Mayo Clinic Definition.

    PubMed

    Christodoulidis, Georgios; Kundoor, Vishwa; Kaluski, Edo

    2017-08-28

    BACKGROUND Various physical and emotional factors have been previously described as triggers for stress induced cardiomyopathy. However, acute myocardial infarction as a trigger has never been reported. CASE REPORT We describe four patients who presented with an acute myocardial infarction, in whom the initial echocardiography revealed wall motion abnormalities extending beyond the coronary distribution of the infarct artery. Of the four patients identified, the mean age was 59 years; three patients were women and two patients had underlying psychiatric history. Electrocardiogram revealed ST elevation in the anterior leads in three patients; QTc was prolonged in all cases. All patients had ≤ moderately elevated troponin. Single culprit lesion was found uniformly in the proximal or mid left anterior descending artery. Initial echocardiography revealed severely reduced ejection fraction with relative sparing of the basal segments, whereas early repeat echocardiography revealed significant improvement in the left ventricular function in all patients. CONCLUSIONS This is the first case series demonstrating that acute myocardial infarction can trigger stress induced cardiomyopathy. Extensive reversible wall motion abnormalities, beyond the ones expected from angiography, accompanied by modest elevation in troponin and marked QTc prolongation, suggest superimposed stress induced cardiomyopathy.

  2. Immune status influences fear and anxiety responses in mice after acute stress exposure

    PubMed Central

    Clark, Sarah M.; Sand, Joseph; Francis, T. Chase; Nagaraju, Anitha; Michael, Kerry C.; Keegan, Achsah D.; Kusnecov, Alexander; Gould, Todd D.; Tonelli, Leonardo H.

    2014-01-01

    Significant evidence suggests that exposure to traumatic and/or acute stress in both mice and humans results in compromised immune function that in turn may affect associated brain processes. Additionally, recent studies in mouse models of immune deficiency have suggested that adaptive immunity may play a role during traumatic stress exposure and that impairments in lymphocyte function may contribute to increased susceptibility to various psychogenic stressors. However, rodent studies on the relationship between maladaptive stress responses and lymphocyte deficiency have been complicated by the fact that genetic manipulations in these models may also result in changes in CNS function due to the expression of targeted genes in tissues other than lymphocytes, including the brain. To address these issues we utilized mice with a deletion of recombination-activating gene 2 (Rag2), which has no confirmed expression in the CNS; thus, its loss should result in the absence of mature lymphocytes without altering CNS function directly. Stress responsiveness of immune deficient Rag2−/− mice on a BALB/c background was evaluated in three different paradigms: predator odor exposure (POE), fear conditioning (FC) and learned helplessness (LH). These models are often used to study different aspects of stress responsiveness after the exposure to an acute stressor. In addition, immunoblot analysis was used to assess hippocampal BDNF expression under both stressed and non-stressed conditions. Subsequent to POE, Rag2−/− mice exhibited a reduced acoustic startle response compared to BALB/c mice; no significant differences in behavior were observed in either FC or LH. Furthermore, analysis of hippocampal BDNF indicated that Rag2−/− mice have elevated levels of the mature form of BDNF compared to BALB/c mice. Results from our studies suggest that the absence of mature lymphocytes is associated with increased resilience to stress exposure in the POE and does not affect

  3. Effects of cumulative stressful and acute variation episodes of farm climate conditions on late embryo/early fetal loss in high producing dairy cows

    NASA Astrophysics Data System (ADS)

    Santolaria, Pilar; López-Gatius, Fernando; García-Ispierto, Irina; Bech-Sàbat, Gregori; Angulo, Eduardo; Carretero, Teresa; Sánchez-Nadal, Jóse Antonio; Yániz, Jesus

    2010-01-01

    The aim of this study was to determine possible relationships between farm climate conditions, recorded from day 0 to day 40 post-artificial insemination (AI), and late embryo/early fetal loss in high producing dairy cows. Pregnancy was diagnosed by rectal ultrasonography between 28 and 34 days post-AI. Fetal loss was registered when a further 80- to 86-day diagnosis proved negative. Climate variables such as air temperature and relative humidity (RH) were monitored in the cubicles area for each 30-min period. Temperature-humidity indices (THI); cumulative stressful values and episodes of acute change (defined as the mean daily value 1.2 times higher or lower than the mean daily values of the 10 previous days) of the climate variables were calculated. The data were derived from 759 cows in one herd. A total of 692 pregnancies (91.2%) carried singletons and 67 (8.8%) carried twins. No triplets were recorded. Pregnancy loss was recorded in 6.7% (51/759) of pregnancies: 5.6% (39/692) in single and 17.9% (12/67) in twin pregnancies. Using logistic regression procedures, a one-unit increase in the daily cumulative number of hours for the THI values higher than 85 during days 11-20 of gestation caused a 1.57-fold increase in the pregnancy loss, whereas the likelihood of fetal loss increased by a factor of 1.16 for each additional episode of acute variation for the maximum THI values during gestation days 0-40. THI values higher than 85 and episodes of acute variation for the maximum THI values were only recorded during the warm and cool periods, respectively. The presence of twins led to a 3.98-fold increase in pregnancy loss. In conclusion, our findings show that cumulative stressful and episodes of acute variation of climatic conditions can compromise the success of gestation during both the cool and warm periods of the year. Twin pregnancy was confirmed as a main factor associated with pregnancy loss.

  4. Acute episodes of predator exposure in conjunction with chronic social instability as an animal model of post-traumatic stress disorder

    PubMed Central

    Zoladz, Phillip R.; Conrad, Cheryl D.; Fleshner, Monika; Diamond, David M.

    2008-01-01

    People who are exposed to horrific, life-threatening experiences are at risk for developing post-traumatic stress disorder (PTSD). Some of the symptoms of PTSD include persistent anxiety, exaggerated startle, cognitive impairments and increased sensitivity to yohimbine, an α2-adrenergic receptor antagonist. We have taken into account the conditions known to induce PTSD, as well as factors responsible for long-term maintenance of the disorder, to develop an animal model of PTSD. Adult male Sprague–Dawley rats were administered a total of 31 days of psychosocial stress, composed of acute and chronic components. The acute component was a 1-h stress session (immobilization during cat exposure), which occurred on Days 1 and 11. The chronic component was that on all 31 days the rats were given unstable housing conditions. We found that psychosocially stressed rats had reduced growth rate, reduced thymus weight, increased adrenal gland weight, increased anxiety, an exaggerated startle response, cognitive impairments, greater cardiovascular and corticosterone reactivity to an acute stressor and heightened responsivity to yohimbine. This work demonstrates the effectiveness of acute inescapable episodes of predator exposure administered in conjunction with daily social instability as an animal model of PTSD. PMID:18574787

  5. Influence of peak oral temperatures on veneer–core interface stress state

    PubMed Central

    Marrelli, Massimo; Pujia, Antonella; Apicella, Davide; Sansalone, Salvatore; Tatullo, Marco

    2015-01-01

    Abstract Objective: There is a growing interest for the use of Y-TZP zirconia as core material in veneered all-ceramic prostheses. The objective of this study was to evaluate the influence of CET on the stress distribution of a porcelain layered to zirconia core single crowns by finite elements analysis. Material and methods: CET of eight different porcelains was considered during the analysis. Results: Results of this study indicated that the mismatch in CET between the veneering porcelain and the Y-TZP zirconia core has to be minimum (0.5–1 μm/mK) so as to decrease the growing of residual stresses which could bring chipping. Conclusions: The stress state due to temperature variation should be carefully taken into consideration while studying the effect of mechanical load on zirconia core crown by FEA. The interfacial stress state can be increased by temperature variation up to 20% with respect to the relative failure parameter (interface strength in this case). This means that stress due to mechanical load combined to temperature variation-induced stress can lead porcelain veneer–zirconia core interfaces to failure. PMID:28642897

  6. The Influence of Acute Handling Stress on Some Blood Parameters in Cultured Sea Bream (Sparus Aurata Linnaeus, 1758)

    PubMed Central

    Fazio, Francesco; Ferrantelli, Vincenzo; Fortino, Gianluca; Giangrosso, Giuseppe; Faggio, Caterina

    2015-01-01

    The effect of acute handling stress on haematological profile, blood glucose and lactate (secondary stress markers) in cultured sea bream Sparus aurata was evaluated. Sixty six Sparus aurata were used and equally divided into two groups (A and B). Group A was not subjected to stress, Group B was subjected to acute handling stress. From each fish, biometric data and blood samples were collected to evaluate haematological profile, blood glucose and lactate. Unpaired t-test Student was applied to evaluate possible differences in parameters between the two groups. Red blood cells, haematocrit, haemoglobin, white blood cells (WBC), glucose and lactate showed an increase (P<0.05) in Group B compared with Group A, while mean corpuscular volume decreased (P<0.05) in Group B. The results highlight the role of studied parameters in monitoring the stressful conditions of aquaculture production which affect animal welfare and fish products quality. PMID:27800375

  7. Persistent Effects of Acute Stress on Fear and Drug-Seeking in a Novel Model of the Comorbidity between Post-Traumatic Stress Disorder and Addiction

    ERIC Educational Resources Information Center

    Pizzimenti, Christie L.; Navis, Tom M.; Lattal, K. Matthew

    2017-01-01

    Even following long periods of abstinence, individuals with anxiety disorders have high rates of relapse to drugs of abuse. Although many current models of relapse demonstrate effects of acute stress on drug-seeking, most of these studies examine stressful experiences that occur in close temporal and physical proximity to the reinstatement test.…

  8. Prior exposure to repeated immobilization or chronic unpredictable stress protects from some negative sequels of an acute immobilization.

    PubMed

    Pastor-Ciurana, Jordi; Rabasa, Cristina; Ortega-Sánchez, Juan A; Sanchís-Ollè, Maria; Gabriel-Salazar, Marina; Ginesta, Marta; Belda, Xavier; Daviu, Núria; Nadal, Roser; Armario, Antonio

    2014-05-15

    Exposure to chronic unpredictable stress (CUS) is gaining acceptance as a putative animal model of depression. However, there is evidence that chronic exposure to stress can offer non-specific stress protection from some effects of acute superimposed stressors. We then compared in adult male rats the protection afforded by prior exposure to CUS with the one offered by repeated immobilization on boards (IMO) regarding some of the negative consequences of an acute exposure to IMO. Repeated exposure to IMO protected from the negative consequences of an acute IMO on activity in an open-field, saccharin intake and body weight gain. Active coping during IMO (struggling) was markedly reduced by repeated exposure to the same stressor, but it was not affected by a prior history of CUS, suggesting that our CUS protocol does not appear to impair active coping responses. CUS exposure itself caused a strong reduction of activity in the open-field but appeared to protect from the hypo-activity induced by acute IMO. Moreover, prior CUS offered partial protection from acute IMO-induced reduction of saccharin intake and body weight gain. It can be concluded that a prior history of CUS protects from some of the negative consequences of exposure to a novel severe stressor, suggesting the development of partial cross-adaptation whose precise mechanisms remain to be studied. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Historical Temperature Variability Affects Coral Response to Heat Stress

    PubMed Central

    Carilli, Jessica; Donner, Simon D.; Hartmann, Aaron C.

    2012-01-01

    Coral bleaching is the breakdown of symbiosis between coral animal hosts and their dinoflagellate algae symbionts in response to environmental stress. On large spatial scales, heat stress is the most common factor causing bleaching, which is predicted to increase in frequency and severity as the climate warms. There is evidence that the temperature threshold at which bleaching occurs varies with local environmental conditions and background climate conditions. We investigated the influence of past temperature variability on coral susceptibility to bleaching, using the natural gradient in peak temperature variability in the Gilbert Islands, Republic of Kiribati. The spatial pattern in skeletal growth rates and partial mortality scars found in massive Porites sp. across the central and northern islands suggests that corals subject to larger year-to-year fluctuations in maximum ocean temperature were more resistant to a 2004 warm-water event. In addition, a subsequent 2009 warm event had a disproportionately larger impact on those corals from the island with lower historical heat stress, as indicated by lower concentrations of triacylglycerol, a lipid utilized for energy, as well as thinner tissue in those corals. This study indicates that coral reefs in locations with more frequent warm events may be more resilient to future warming, and protection measures may be more effective in these regions. PMID:22479626

  10. Effects of copper, hypoxia and acute temperature shifts on mitochondrial oxidation in rainbow trout (Oncorhynchus mykiss) acclimated to warm temperature.

    PubMed

    Sappal, Ravinder; Fast, Mark; Stevens, Don; Kibenge, Fred; Siah, Ahmed; Kamunde, Collins

    2015-12-01

    Temperature fluctuations, hypoxia and metals pollution frequently occur simultaneously or sequentially in aquatic systems and their interactions may confound interpretation of their biological impacts. With a focus on energy homeostasis, the present study examined how warm acclimation influences the responses and interactions of acute temperature shift, hypoxia and copper (Cu) exposure in fish. Rainbow trout (Oncorhynchus mykiss) were acclimated to cold (11°C; control) and warm (20°C) temperature for 3 weeks followed by exposure to environmentally realistic levels of Cu and hypoxia for 24h. Subsequently, mitochondrial electron transport system (ETS) respiratory activity supported by complexes I-IV (CI-IV), plasma metabolites and condition indices were measured. Warm acclimation reduced fish condition, induced aerobic metabolism and altered the responses of fish to acute temperature shift, hypoxia and Cu. Whereas warm acclimation decelerated the ETS and increased the sensitivity of maximal oxidation rates of the proximal (CI and II) complexes to acute temperature shift, it reduced the thermal sensitivity of state 4 (proton leak). Effects of Cu with and without hypoxia were variable depending on the acclimation status and functional index. Notably, Cu stimulated respiratory activity in the proximal ETS segments, while hypoxia was mostly inhibitory and minimized the stimulatory effect of Cu. The effects of Cu and hypoxia were modified by temperature and showed reciprocal antagonistic interaction on the ETS and plasma metabolites, with modest additive actions limited to CII and IV state 4. Overall, our results indicate that warm acclimation came at a cost of reduced ETS efficiency and increased sensitivity to added stressors. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Acute stress causes rapid synaptic insertion of Ca2+-permeable AMPA receptors to facilitate long-term potentiation in the hippocampus

    PubMed Central

    Jo, Jihoon; Hogg, Ellen L.; Piers, Thomas; Kim, Dong-Hyun; Seaton, Gillian; Seok, Heon; Bru-Mercier, Gilles; Son, Gi Hoon; Regan, Philip; Hildebrandt, Lars; Waite, Eleanor; Kim, Byeong-Chae; Kerrigan, Talitha L.; Kim, Kyungjin; Whitcomb, Daniel J.; Lightman, Stafford L.

    2013-01-01

    The neuroendocrine response to episodes of acute stress is crucial for survival whereas the prolonged response to chronic stress can be detrimental. Learning and memory are particularly susceptible to stress with cognitive deficits being well characterized consequences of chronic stress. Although there is good evidence that acute stress can enhance cognitive performance, the mechanism(s) for this are unclear. We find that hippocampal slices, either prepared from rats following 30 min restraint stress or directly exposed to glucocorticoids, exhibit an N-methyl-d-aspartic acid receptor-independent form of long-term potentiation. We demonstrate that the mechanism involves an NMDA receptor and PKA-dependent insertion of Ca2+-permeable AMPA receptors into synapses. These then trigger the additional NMDA receptor-independent form of LTP during high frequency stimulation. PMID:24271563

  12. Seawater inhalation induces acute lung injury via ROS generation and the endoplasmic reticulum stress pathway.

    PubMed

    Li, Peng-Cheng; Wang, Bo-Rong; Li, Cong-Cong; Lu, Xi; Qian, Wei-Sheng; Li, Yu-Juan; Jin, Fa-Guang; Mu, De-Guang

    2018-05-01

    Seawater (SW) inhalation can induce acute lung injury (ALI) and acute respiratory distress syndrome (ARDS). In the present study, SW induced apoptosis of rat alveolar epithelial cells and histopathological alterations to lung tissue. Furthermore, SW administration increased generation of reactive oxygen species (ROS), whereas pretreatment with the ROS scavenger, N‑acetyl‑L‑cysteine (NAC), significantly decreased ROS generation, apoptosis and histopathological alterations. In addition, SW exposure upregulated the expression levels of glucose‑regulated protein 78 (GRP78) and CCAAT/enhancer binding protein homologous protein (CHOP), which are critical proteins in the endoplasmic reticulum (ER) stress response, thus indicating that SW may activate ER stress. Conversely, blocking ER stress with 4‑phenylbutyric acid (4‑PBA) significantly improved SW‑induced apoptosis and histopathological alterations, whereas an ER stress inducer, thapsigargin, had the opposite effect. Furthermore, blocking ROS with NAC inhibited SW‑induced ER stress, as evidenced by the downregulation of GRP78, phosphorylated (p)‑protein kinase R‑like ER kinase (PERK), p‑inositol‑requiring kinase 1α (IRE1α), p‑50 activating transcription factor 6α and CHOP. In addition, blocking ER stress with 4‑PBA decreased ROS generation. In conclusion, the present study indicated that ROS and ER stress pathways, which are involved in alveolar epithelial cell apoptosis, are important in the pathogenesis of SW‑induced ALI.

  13. Temperatures and Stresses on Hollow Blades For Gas Turbines

    NASA Technical Reports Server (NTRS)

    Pollmann, Erich

    1947-01-01

    The present treatise reports on theoretical investigations and test-stand measurements which were carried out in the BMW Flugmotoren GMbH in developing the hollow blade for exhaust gas turbines. As an introduction the temperature variation and the stress on a turbine blade for a gas temperature of 900 degrees and circumferential velocities of 600 meters per second are discussed. The assumptions onthe heat transfer coefficients at the blade profile are supported by tests on an electrically heated blade model. The temperature distribution in the cross section of a blade Is thoroughly investigated and the temperature field determined for a special case. A method for calculation of the thermal stresses in turbine blades for a given temperature distribution is indicated. The effect of the heat radiation on the blade temperature also is dealt with. Test-stand experiments on turbine blades are evaluated, particularly with respect to temperature distribution in the cross section; maximum and minimum temperature in the cross section are ascertained. Finally, the application of the hollow blade for a stationary gas turbine is investigated. Starting from a setup for 550 C gas temperature the improvement of the thermal efficiency and the fuel consumption are considered as well as the increase of the useful power by use of high temperatures. The power required for blade cooling is taken into account.

  14. Acute stress alters transcript expression pattern and reduces processing of proBDNF to mature BDNF in Dicentrarchus labrax

    PubMed Central

    2010-01-01

    Background Stress involves alterations of brain functioning that may precipitate to mood disorders. The neurotrophin Brain Derived Neurotrophic Factor (BDNF) has recently been involved in stress-induced adaptation. BDNF is a key regulator of neuronal plasticity and adaptive processes. Regulation of BDNF is complex and may reflect not only stress-specific mechanisms but also hormonal and emotional responses. For this reason we used, as an animal model of stress, a fish whose brain organization is very similar to that of higher vertebrates, but is generally considered free of emotional reactions. Results We provide a comprehensive characterization of BDNF gene in the Dicentrarchus labrax and its transcriptional, translational and post-translational regulation following acute stress. While total BDNF mRNA levels are unchanged, BDNF transcripts 1c and 1d resulted down regulated after acute stress. Acute stress induces also a significant increase in proBDNF levels and reduction in mature BDNF suggesting altered regulation of proBDNF proteolytic processing. Notably, we provide here the first evidence that fishes possess a simplified proteolytic regulation of BDNF since the pro28Kda form, generated by the SKI-1 protease in mammals, is absent in fishes because the cleavage site has first emerged in reptilians. Finally, we show that the proBDNF/totBDNF ratio is a highly predictive novel quantitative biomarker to detect stress in fishes with sensitivity = 100%, specificity = 87%, and Negative Predictive Value = 100%. Conclusion The high predictivity of proBDNF/totBDNF ratio for stress in lower vertebrates indicates that processing of BDNF is a central mechanism in adaptation to stress and predicts that a similar regulation of pro/mature BDNF has likely been conserved throughout evolution of vertebrates from fish to man. PMID:20074340

  15. Acute stress alters transcript expression pattern and reduces processing of proBDNF to mature BDNF in Dicentrarchus labrax.

    PubMed

    Tognoli, Chiara; Rossi, Federica; Di Cola, Francesco; Baj, Gabriele; Tongiorgi, Enrico; Terova, Genciana; Saroglia, Marco; Bernardini, Giovanni; Gornati, Rosalba

    2010-01-14

    Stress involves alterations of brain functioning that may precipitate to mood disorders. The neurotrophin Brain Derived Neurotrophic Factor (BDNF) has recently been involved in stress-induced adaptation. BDNF is a key regulator of neuronal plasticity and adaptive processes. Regulation of BDNF is complex and may reflect not only stress-specific mechanisms but also hormonal and emotional responses. For this reason we used, as an animal model of stress, a fish whose brain organization is very similar to that of higher vertebrates, but is generally considered free of emotional reactions. We provide a comprehensive characterization of BDNF gene in the Dicentrarchus labrax and its transcriptional, translational and post-translational regulation following acute stress. While total BDNF mRNA levels are unchanged, BDNF transcripts 1c and 1d resulted down regulated after acute stress. Acute stress induces also a significant increase in proBDNF levels and reduction in mature BDNF suggesting altered regulation of proBDNF proteolytic processing. Notably, we provide here the first evidence that fishes possess a simplified proteolytic regulation of BDNF since the pro28Kda form, generated by the SKI-1 protease in mammals, is absent in fishes because the cleavage site has first emerged in reptilians. Finally, we show that the proBDNF/totBDNF ratio is a highly predictive novel quantitative biomarker to detect stress in fishes with sensitivity = 100%, specificity = 87%, and Negative Predictive Value = 100%. The high predictivity of proBDNF/totBDNF ratio for stress in lower vertebrates indicates that processing of BDNF is a central mechanism in adaptation to stress and predicts that a similar regulation of pro/mature BDNF has likely been conserved throughout evolution of vertebrates from fish to man.

  16. Plasma omega 3 polyunsaturated fatty acid status and monounsaturated fatty acids are altered by chronic social stress and predict endocrine responses to acute stress in titi monkeys

    USDA-ARS?s Scientific Manuscript database

    Disturbances in fatty acid (FA) metabolism may link chronic psychological stress, endocrine responsiveness, and psychopathology. Therefore, lipid metabolome-wide responses and their relationships with endocrine (cortisol; insulin; adiponectin) responsiveness to acute stress (AS) were assessed in a ...

  17. Talofibular interval changes after acute ankle sprain: a stress ultrasonography study of ankle laxity.

    PubMed

    Croy, Theodore; Saliba, Susan; Saliba, Ethan; Anderson, Mark W; Hertel, Jay

    2013-11-01

    Quantifying talocrural joint laxity after ankle sprain is problematic. Stress ultrasonography (US) can image the lateral talocrural joint and allow the measurement of the talofibular interval, which may suggest injury to the anterior talofibular ligament (ATFL). The acute talofibular interval changes after lateral ankle sprain are unknown. Twenty-five participants (9 male, 16 female; age 21.8 ± 3.2 y, height 167.8 ± 34.1 cm, mass 72.7 ± 13.8 kg) with 27 acute, lateral ankle injuries underwent bilateral stress US imaging at baseline (<7 d) and on the affected ankle at 3 wk and 6 wk from injury in 3 ankle conditions: neutral, anterior drawer, and inversion. Talofibular interval (mm) was measured using imaging software and self-reported function (activities of daily living [ADL] and sports) by the Foot and Ankle Ability Measure (FAAM). The talofibular interval increased with anterior-drawer stress in the involved ankle (22.65 ± 3.75 mm; P = .017) over the uninvolved ankle (19.45 ± 2.35 mm; limb × position F1,26 = 4.9, P = .035) at baseline. Inversion stress also resulted in greater interval changes (23.41 ± 2.81 mm) than in the uninvolved ankles (21.13 ± 2.08 mm). A main effect for time was observed for inversion (F2,52 = 4.3, P = .019, 21.93 ± 2.24 mm) but not for anterior drawer (F2,52 = 3.1, P = .055, 21.18 ± 2.34 mm). A significant reduction in the talofibular interval took place between baseline and week 3 inversion measurements only (F1,26 = 5.6, P = .026). FAAM-ADL and sports results increased significantly from baseline to wk 3 (21.9 ± 16.2, P < .0001 and 23.8 ± 16.9, P < .0001) and from wk 3 to wk 6 (2.5 ± 4.4, P = .009 and 10.5 ± 13.2, P = .001). Stress US methods identified increased talofibular interval changes suggestive of talocrural laxity and ATFL injury using anterior drawer and inversion stress that, despite significant improvements in self-reported function, only marginally improved during the 6 wk after ankle sprain. Stress US

  18. Symptom Differences in Acute and Chronic Presentation of Childhood Post-Traumatic Stress Disorder.

    ERIC Educational Resources Information Center

    Famularo, Richard; And Others

    1990-01-01

    Twenty-four child abuse victims, age 5-13, were diagnosed with posttraumatic stress disorder (PTSD). Children with the acute form of PTSD exhibited such symptoms as difficulty falling asleep, hypervigilance, nightmares, and generalized anxiety. Children exhibiting chronic PTSD exhibited increased detachment, restricted range of affect,…

  19. Initial evaluation of floor cooling on lactating sows under severe acute heat stress

    USDA-ARS?s Scientific Manuscript database

    The objectives were to evaluate an acute heat stress protocol for lactating sows and evaluate preliminary estimates of water flow rates required to cool sows. Twelve multiparous sows were provided with a cooling pad built with an aluminum plate surface, high-density polyethylene base and copper pipe...

  20. Cross-talk between oxidative stress and pro-inflammatory cytokines in acute pancreatitis: a key role for protein phosphatases.

    PubMed

    Escobar, Javier; Pereda, Javier; Arduini, Alessandro; Sandoval, Juan; Sabater, Luis; Aparisi, Luis; López-Rodas, Gerardo; Sastre, Juan

    2009-01-01

    Acute pancreatitis is an acute inflammatory process localized in the pancreatic gland that frequently involves peripancreatic tissues. It is still under investigation why an episode of acute pancreatitis remains mild affecting only the pancreas or progresses to a severe form leading to multiple organ failure and death. Proinflammatory cytokines and oxidative stress play a pivotal role in the early pathophysiological events of the disease. Cytokines such as interleukin 1beta and tumor necrosis factor alpha initiate and propagate almost all consequences of the systemic inflammatory response syndrome. On the other hand, depletion of pancreatic glutathione is an early hallmark of acute pancreatitis and reactive oxygen species are also associated with the inflammatory process. Changes in thiol homestasis and redox signaling decisively contribute to amplification of the inflammatory cascade through mitogen activated protein kinase (MAP kinase) pathways. This review focuses on the relationship between oxidative stress, pro-inflammatory cytokines and MAP kinase/protein phosphatase pathways as major modulators of the inflammatory response in acute pancreatitis. Redox sensitive signal transduction mediated by inactivation of protein phosphatases, particularly protein tyrosin phosphatases, is highlighted.

  1. Stress does not increase blood–brain barrier permeability in mice

    PubMed Central

    Roszkowski, Martin

    2016-01-01

    Several studies have reported that exposure to acute psychophysiological stressors can lead to an increase in blood–brain barrier permeability, but these findings remain controversial and disputed. We thoroughly examined this issue by assessing the effect of several well-established paradigms of acute stress and chronic stress on blood–brain barrier permeability in several brain areas of adult mice. Using cerebral extraction ratio for the small molecule tracer sodium fluorescein (NaF, 376 Da) as a sensitive measure of blood–brain barrier permeability, we find that neither acute swim nor restraint stress lead to increased cerebral extraction ratio. Daily 6-h restraint stress for 21 days, a model for the severe detrimental impact of chronic stress on brain function, also does not alter cerebral extraction ratio. In contrast, we find that cold forced swim and cold restraint stress both lead to a transient, pronounced decrease of cerebral extraction ratio in hippocampus and cortex, suggesting that body temperature can be an important confounding factor in studies of blood–brain barrier permeability. To additionally assess if stress could change blood–brain barrier permeability for macromolecules, we measured cerebral extraction ratio for fluorescein isothiocyanate-dextran (70 kDa). We find that neither acute restraint nor cold swim stress affected blood–brain barrier permeability for macromolecules, thus corroborating our findings that various stressors do not increase blood–brain barrier permeability. PMID:27146513

  2. The stressed female brain: neuronal activity in the prelimbic but not infralimbic region of the medial prefrontal cortex suppresses learning after acute stress.

    PubMed

    Maeng, Lisa Y; Shors, Tracey J

    2013-01-01

    Women are nearly twice as likely as men to suffer from anxiety and post-traumatic stress disorder (PTSD), indicating that many females are especially vulnerable to stressful life experience. A profound sex difference in the response to stress is also observed in laboratory animals. Acute exposure to an uncontrollable stressful event disrupts associative learning during classical eyeblink conditioning in female rats but enhances this same type of learning process in males. These sex differences in response to stress are dependent on neuronal activity in similar but also different brain regions. Neuronal activity in the basolateral nucleus of the amygdala (BLA) is necessary in both males and females. However, neuronal activity in the medial prefrontal cortex (mPFC) during the stressor is necessary to modify learning in females but not in males. The mPFC is often divided into its prelimbic (PL) and infralimbic (IL) subregions, which differ both in structure and function. Through its connections to the BLA, we hypothesized that neuronal activity within the PL, but not IL, during the stressor is necessary to suppress learning in females. To test this hypothesis, either the PL or IL of adult female rats was bilaterally inactivated with GABAA agonist muscimol during acute inescapable swim stress. About 24 h later, all subjects were trained with classical eyeblink conditioning. Though stressed, females without neuronal activity in the PL learned well. In contrast, females with IL inactivation during the stressor did not learn well, behaving similarly to stressed vehicle-treated females. These data suggest that exposure to a stressful event critically engages the PL, but not IL, to disrupt associative learning in females. Together with previous studies, these data indicate that the PL communicates with the BLA to suppress learning after a stressful experience in females. This circuit may be similarly engaged in women who become cognitively impaired after stressful life

  3. Sleep quality but not sleep quantity effects on cortisol responses to acute psychosocial stress

    PubMed Central

    Bassett, Sarah M.; Lupis, Sarah B.; Gianferante, Danielle; Rohleder, Nicolas; Wolf, Jutta M.

    2016-01-01

    Given the well-documented deleterious health effects, poor sleep has become a serious public health concern and increasing efforts are directed towards understanding underlying pathways. One potential mechanism may be stress and its biological correlates; however, studies investigating the effects of poor sleep on a body’s capacity to deal with challenges are lacking. The current study thus aimed at testing the effects of sleep quality and sleep quantity on cortisol responses to acute psychosocial stress. A total of 73 college-aged adults (44 females) were investigated. Self-reported sleep behavior was assessed via the Pittsburgh Sleep Quality Index and salivary cortisol responses to the Trier Social Stress Test (TSST) were measured. In terms of sleep quality, we found a significant three-way interaction, such that relative to bad sleep quality, men who reported fairly good or very good sleep quality showed blunted or exaggerated cortisol responses, respectively, while women’s stress responses were less dependent on their self-reported sleep quality. Contrarily, average sleep duration did not appear to impact cortisol stress responses. Lastly, participants who reported daytime dysfunctions (i.e., having trouble staying awake or keeping up enthusiasm) also showed a trend to blunted cortisol stress responses compared to participants who did not experience these types of daytime dysfunctions. Overall, the current study suggests gender-specific stress reactivity dysfunctions as one mechanism linking poor sleep with detrimental physical health outcomes. Furthermore, the observed differential sleep effects may indicate that while the body may be unable to maintain normal HPA functioning in an acute psychosocial stress situation after falling prey to low sleep quality, it may retain capacities to deal with challenges during extended times of sleep deprivation. PMID:26414625

  4. Trait Hostility and Acute Inflammatory Responses to Stress in the Laboratory

    PubMed Central

    Girard, Dominique; Tardif, Jean-Claude; Boisclair Demarble, Julie; D’Antono, Bianca

    2016-01-01

    Hostility has been associated with higher basal levels of inflammation. The present study evaluated the association of hostility with acute stress-induced changes in inflammatory activity. One hundred and ninety-nine healthy men and women, aged 19–64 years, were exposed to a stress protocol involving four interpersonal stressors. Participants completed the Cook-Medley Hostility questionnaire and provided two blood samples for the measurement of inflammatory biomarkers (CRP, Il-6, MPO, TNF-α, MCP-1, Il-8, Il-10, and Il-18), prior to and following exposure to a standardized stress protocol. In univariate analyses, hostility was associated with significantly higher TNF-α, but lower Il-8 and Il-18 values post-stress, though only Il-8 remained significant after controlling for baseline differences. In multivariate analyses, a significant Age by Hostility interaction emerged for Il-6, while sex moderated the relation between hostility and Il-10 reactivity. Following stress, hostility was associated with greater pro-inflammatory Il-6 activity among younger individuals and to decreased anti-inflammatory Il-10 activity in women. Future research is needed to replicate these findings and to evaluate their implication for disease. PMID:27270459

  5. Differential modulatory effects of morphine on acute and chronic stress induced neurobehavioral and cellular markers in rats.

    PubMed

    Joshi, Jagdish C; Ray, Arunabha; Gulati, Kavita

    2014-04-15

    The present study evaluated the effects of morphine treatments on elevated plus maze test parameters, oxidative stress markers and Hsp70 expression in normal and stressed rats. Acute and chronic stress caused neurobehavioral suppression, altered prooxidant-antioxidant balance and increased Hsp70 expression in brain homogenates in a differential manner. Morphine (1 and 5mg/kg) attenuated RS induced anxiogenesis, changes in MDA and GSH but further enhanced Hsp70 expression. Similar anxiolytic and Hsp70 enhancing effects were seen after morphine in normal rats (no RS). Exposure to chronic RS did not elicit any appreciable neurobehavioral response in EPM but enhanced MDA, lowered GSH and exaggerated the Hsp70 expression. Pretreatment with morphine did not affect the neurobehavioral response to chronic RS, but reverted the GSH and Hsp70 expression. The results suggest that morphine differentially influences acute and chronic stress induced changes in anxiety behavior and complex interactions between oxidative stress markers and Hsp70 expression which may contribute to these effects. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Lycopersicon esculentum under low temperature stress: an approach toward enhanced antioxidants and yield.

    PubMed

    Khan, Tanveer Alam; Fariduddin, Qazi; Yusuf, Mohammad

    2015-09-01

    Brassinosteroids (BRs) have been implicated to overcome various abiotic stresses, and low temperature stress poses a serious threat to productivity of various horticultural crops like tomato. Therefore, a study was conducted to unravel the possible role of BRs in conferring alleviation to low temperature stress in Lycopersicon esculentum. Twenty-day-old seedlings of tomato var. S-22 (chilling tolerant) and PKM-1 (chilling sensitive) were sown in earthen pots, and at 40 days stage of growth, plants were exposed to varied levels of low temperatures (10/3, 12/7, 20/14, or 25/18 °C) for 24 h in a growth chamber. At 50 days stage of growth, the foliage of plants were sprayed with 0 or 10(-8) M of BRs (28-homobrassinolide or 24-epibrassinolide), and 60-day-old plants were harvested to assess various physiological and biochemical parameters. Low temperatures induced a significant reduction in growth traits, chlorophyll content, and rate of photosynthesis in both the varieties differentially. Activities of antioxidant enzymes (catalase, peroxidase, and superoxide dismutase) and leaf proline content also increased substantially in both the varieties with decreasing temperature. On the other hand, treatment of BRs under stress and stress-free conditions significantly increased the aforesaid growth traits and biochemical parameters. Moreover, BRs further accelerated the antioxidative enzymes and proline content, which were already enhanced by the low temperature stress. Out of the two analogues of BRs tested, 24-epibrassinolide (EBL) was found more effective for both the varieties of tomato. EBL was found more potent stress alleviator against low temperature in both varieties of tomato.

  7. HPA-axis and inflammatory reactivity to acute stress is related with basal HPA-axis activity.

    PubMed

    Chen, Xuejie; Gianferante, Danielle; Hanlin, Luke; Fiksdal, Alexander; Breines, Juliana G; Thoma, Myriam V; Rohleder, Nicolas

    2017-04-01

    Inflammation is drawing attention as pathway between psychosocial stress and health, and basal HPA axis activity has been suggested to exert a consistent regulatory influence on peripheral inflammation. Here we studied the relationship between basal HPA axis activity and inflammatory and HPA axis acute stress reactivity. We recruited 48 healthy individuals and collected saliva for diurnal cortisol sampling at 6 points. Participants were previously exposed to the Trier Social Stress Test (TSST) on two consecutive days. Plasma interleukin-6 (IL-6) and salivary cortisol reactivity to acute stress were measured, and their relationships with basal HPA axis activity were analyzed. Steeper cortisol awakening response (CAR) linear increase was related with stronger cortisol stress reactivity (γ=0.015; p=0.042) and marginally significantly with greater habituation (γ=0.01; p=0.066). Greater curvilinearity of CAR was related with stronger cortisol reactivity (γ=-0.014; p=0.021) and greater cortisol habituation (γ=-0.011; p=0.006). Steeper daily linear decline was related with significant or marginally significantly stronger cortisol and IL-6 reactivity (cortisol: γ=-0.0004; p=0.06; IL-6: γ=-0.028; p=0.031) and greater habituation (cortisol: γ=-0.002; p=0.009, IL-6: γ=-0.015; p=0.033). Greater curvilinearity of daily decline was related with stronger IL-6 reactivity (γ=0.002; p=0.024) and also greater cortisol and IL-6 habituation (cortisol: γ=0.00009; p=0.03, IL-6: γ=0.001; p=0.024). Patterns of basal HPA axis activity that are related with healthier outcomes were found to be related with stronger initial cortisol and IL-6 reactivity and greater habituation. This is an important step in understanding the long-term health implications of acute stress responsiveness, and future studies should employ longitudinal designs to identify the direction of these relationships. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Progranulin Protects Hippocampal Neurogenesis via Suppression of Neuroinflammatory Responses Under Acute Immune Stress.

    PubMed

    Ma, Yanbo; Matsuwaki, Takashi; Yamanouchi, Keitaro; Nishihara, Masugi

    2017-07-01

    Immune stress is well known to suppress adult neurogenesis in the hippocampus. We have demonstrated that progranulin (PGRN) has a mitogenic effect on neurogenesis under several experimental conditions. We have also shown that PGRN suppresses excessive neuroinflammatory responses after traumatic brain injury. However, the role of PGRN in modulating neurogenesis under acute immune stress is yet to be elucidated. In the present study, we evaluated the involvement of PGRN in neurogenesis and inflammatory responses in the hippocampus using a lipopolysaccharide (LPS)-induced immune stress model. Treatment of mice with LPS significantly increased the expression of PGRN in activated microglia and decreased neurogenesis in the dentate gyrus of the hippocampus. PGRN deficiency increased CD68-immunoreactive area and exacerbated suppression of neurogenesis following LPS treatment. The expression levels of lysosomal genes including lysozyme M, macrophage expressed gene 1, and cathepsin Z were higher in PGRN-deficient than in wild-type mice, while PGRN deficiency decreased mammalian target of rapamycin (mTOR) mRNA levels, suggesting that PGRN suppresses excessive lysosomal biogenesis by promoting mTOR signaling. LPS treatment also increased the expression of proinflammatory genes such as interleukin (IL)-1β, tumor necrosis factor-α, and microsomal prostaglandin E synthase-1 (mPGES-1) in the hippocampus, and PGRN deficiency further enhanced gene expression of IL-6 and mPGES-1. These results suggest that PGRN plays a protecting role in hippocampal neurogenesis at least partially by attenuating neuroinflammatory responses during LPS-induced acute immune stress.

  9. Distinct Trajectories of Cortisol Response to Prolonged Acute Stress Are Linked to Affective Responses and Hippocampal Gray Matter Volume in Healthy Females

    PubMed Central

    Treadway, Michael T.; Valeri, Linda; Douglas, Samuel

    2017-01-01

    The development of robust laboratory procedures for acute stress induction over the last decades has greatly advanced our understanding of stress responses in humans and their underlying neurobiological mechanisms. Nevertheless, attempts to uncover linear relationships among endocrine, neural, and affective responses to stress have generally yielded inconsistent results. Here, 79 healthy females completed a well established laboratory procedure of acute stress induction that was modified to prolong its effect. Endocrinological and subjective affect assessments revealed stress-induced increases in cortisol release and negative affect that persisted 65 and 100 min after stress onset, respectively, confirming a relatively prolonged acute stress induction. Applying latent class linear mixed modeling on individuals' patterns of cortisol responses identified three distinct trajectories of cortisol response: the hyper-response (n = 10), moderate-response (n = 21), and mild-response (n = 48) groups. Notably, whereas all three groups exhibited a significant stress-induced increase in cortisol release and negative affect, the hyper-response and mild-response groups both reported more negative affect relative to the moderate-response group. Structural MRI revealed no group differences in hippocampal and amygdala volumes, yet a continuous measure of cortisol response (area under the curve) showed that high and low levels of stress-induced cortisol release were associated with less hippocampal gray matter volume compared with moderate cortisol release. Together, these results suggest that distinct trajectories of cortisol response to prolonged acute stress among healthy females may not be captured by conventional linear analyses; instead, quadratic relations may better describe links between cortisol response to stress and affective responses, as well as hippocampal structural variability. SIGNIFICANCE STATEMENT Despite substantial research, it is unclear whether and how

  10. Distinct Trajectories of Cortisol Response to Prolonged Acute Stress Are Linked to Affective Responses and Hippocampal Gray Matter Volume in Healthy Females.

    PubMed

    Admon, Roee; Treadway, Michael T; Valeri, Linda; Mehta, Malavika; Douglas, Samuel; Pizzagalli, Diego A

    2017-08-16

    The development of robust laboratory procedures for acute stress induction over the last decades has greatly advanced our understanding of stress responses in humans and their underlying neurobiological mechanisms. Nevertheless, attempts to uncover linear relationships among endocrine, neural, and affective responses to stress have generally yielded inconsistent results. Here, 79 healthy females completed a well established laboratory procedure of acute stress induction that was modified to prolong its effect. Endocrinological and subjective affect assessments revealed stress-induced increases in cortisol release and negative affect that persisted 65 and 100 min after stress onset, respectively, confirming a relatively prolonged acute stress induction. Applying latent class linear mixed modeling on individuals' patterns of cortisol responses identified three distinct trajectories of cortisol response: the hyper-response ( n = 10), moderate-response ( n = 21), and mild-response ( n = 48) groups. Notably, whereas all three groups exhibited a significant stress-induced increase in cortisol release and negative affect, the hyper-response and mild-response groups both reported more negative affect relative to the moderate-response group. Structural MRI revealed no group differences in hippocampal and amygdala volumes, yet a continuous measure of cortisol response (area under the curve) showed that high and low levels of stress-induced cortisol release were associated with less hippocampal gray matter volume compared with moderate cortisol release. Together, these results suggest that distinct trajectories of cortisol response to prolonged acute stress among healthy females may not be captured by conventional linear analyses; instead, quadratic relations may better describe links between cortisol response to stress and affective responses, as well as hippocampal structural variability. SIGNIFICANCE STATEMENT Despite substantial research, it is unclear whether and how

  11. Effects of acute and chronic stress on telencephalic neurochemistry and gene expression in rainbow trout (Oncorhynchus mykiss).

    PubMed

    Moltesen, Maria; Laursen, Danielle Caroline; Thörnqvist, Per-Ove; Andersson, Madelene Åberg; Winberg, Svante; Höglund, Erik

    2016-12-15

    By filtering relevant sensory inputs and initiating stress responses, the brain is an essential organ in stress coping and adaptation. However, exposure to chronic or repeated stress can lead to allostatic overload, where neuroendocrinal and behavioral reactions to stress become maladaptive. This work examines forebrain mechanisms involved in allostatic processes in teleost fishes. Plasma cortisol, forebrain serotonergic (5-HTergic) neurochemistry, and mRNA levels of corticotropin-releasing factor (CRF), CRF-binding protein (CRF-BP), CRF receptors (CRFR1 and CRFR2), mineralocorticoid receptor (MR), glucocorticoid receptors (GR1 and GR2) and serotonin type 1A (5-HT 1A ) receptors (5-HT 1Aα and 5-HT 1Aβ ) were investigated at 1 h before and 0, 1 and 4 h after acute stress, in two groups of rainbow trout held in densities of 25 and 140 kg m -3 for 28 days. Generally, being held at 140 kg m -3 resulted in a less pronounced cortisol response. This effect was also reflected in lower forebrain 5-HTergic turnover, but not in mRNA levels in any of the investigated genes. This lends further support to reports that allostatic load causes fish to be incapable of mounting a proper cortisol response to an acute stressor, and suggests that changes in forebrain 5-HT metabolism are involved in allostatic processes in fish. Independent of rearing densities, mRNA levels of 5-HT 1Aα and MR were downregulated 4 h post-stress compared with values 1 h post-stress, suggesting that these receptors are under feedback control and take part in the downregulation of the hypothalamic-pituitary-interrenal (HPI) axis after exposure to an acute stressor. © 2016. Published by The Company of Biologists Ltd.

  12. Identification of miRNAs and their targets in wild tomato at moderately and acutely elevated temperatures by high-throughput sequencing and degradome analysis

    PubMed Central

    Zhou, Rong; Wang, Qian; Jiang, Fangling; Cao, Xue; Sun, Mintao; Liu, Min; Wu, Zhen

    2016-01-01

    MicroRNAs (miRNAs) are 19–24 nucleotide (nt) noncoding RNAs that play important roles in abiotic stress responses in plants. High temperatures have been the subject of considerable attention due to their negative effects on plant growth and development. Heat-responsive miRNAs have been identified in some plants. However, there have been no reports on the global identification of miRNAs and their targets in tomato at high temperatures, especially at different elevated temperatures. Here, three small-RNA libraries and three degradome libraries were constructed from the leaves of the heat-tolerant tomato at normal, moderately and acutely elevated temperatures (26/18 °C, 33/33 °C and 40/40 °C, respectively). Following high-throughput sequencing, 662 conserved and 97 novel miRNAs were identified in total with 469 conserved and 91 novel miRNAs shared in the three small-RNA libraries. Of these miRNAs, 96 and 150 miRNAs were responsive to the moderately and acutely elevated temperature, respectively. Following degradome sequencing, 349 sequences were identified as targets of 138 conserved miRNAs, and 13 sequences were identified as targets of eight novel miRNAs. The expression levels of seven miRNAs and six target genes obtained by quantitative real-time PCR (qRT-PCR) were largely consistent with the sequencing results. This study enriches the number of heat-responsive miRNAs and lays a foundation for the elucidation of the miRNA-mediated regulatory mechanism in tomatoes at elevated temperatures. PMID:27653374

  13. Stress, catecholaminergic system and cancer.

    PubMed

    Krizanova, O; Babula, P; Pacak, K

    2016-07-01

    Stress as a modern civilization factor significantly affects our lives. While acute stress might have a positive effect on the organism, chronic stress is usually detrimental and might lead to serious health complications. It is known that stress induced by the physical environment (temperature-induced cold stress) can significantly impair the efficacy of cytotoxic chemotherapies and the anti-tumor immune response. On the other hand, epidemiological evidence has shown that patients taking drugs known as β-adrenergic antagonists ("β-blockers"), which are commonly prescribed to treat arrhythmia, hypertension, and anxiety, have significantly lower rates of several cancers. In this review, we summarize the current knowledge about catecholamines as important stress hormones in tumorigenesis and discuss the use of β-blockers as the potential therapeutic agents.

  14. The Nature of Trauma Memories in Acute Stress Disorder in Children and Adolescents

    ERIC Educational Resources Information Center

    Salmond, C. H.; Meiser-Stedman, R.; Glucksman, E.; Thompson, P.; Dalgleish, T.; Smith, P.

    2011-01-01

    Background: There is increasing theoretical, clinical and research evidence for the role of trauma memory in the aetiology of acute pathological stress responses in adults. However, research into the phenomenology of trauma memories in young people is currently scarce. Methods: This study compared the nature of trauma narratives to narratives of…

  15. Acute thermal stressor increases glucocorticoid response but minimizes testosterone and locomotor performance in the cane toad (Rhinella marina).

    PubMed

    Narayan, Edward J; Hero, Jean-Marc

    2014-01-01

    Climatic warming is a global problem and acute thermal stressor in particular could be considered as a major stressor for wildlife. Cane toads (Rhinella marina) have expanded their range into warmer regions of Australia and they provide a suitable model species to study the sub-lethal impacts of thermal stressor on the endocrine physiology of amphibians. Presently, there is no information to show that exposure to an acute thermal stressor could initiate a physiological stress (glucocorticoid) response and secondly, the possible effects on reproductive hormones and performance. Answering these questions is important for understanding the impacts of extreme temperature on amphibians. In this study, we experimented on cane toads from Queensland, Australia by acclimating them to mildly warm temperature (25°C) and then exposing to acute temperature treatments of 30°, 35° or 40°C (hypothetical acute thermal stressors). We measured acute changes in the stress hormone corticosterone and the reproductive hormone testosterone using standard capture and handling protocol and quantified the metabolites of both hormones non-invasively using urinary enzyme-immunoassays. Furthermore, we measured performance trait (i.e. righting response score) in the control acclimated and the three treatment groups. Corticosterone stress responses increased in all toads during exposure to an acute thermal stressor. Furthermore, exposure to a thermal stressor also decreased testosterone levels in all toads. The duration of the righting response (seconds) was longer for toads that were exposed to 40°C than to 30°, 35° or 25°C. The increased corticosterone stress response with increased intensity of the acute thermal stressor suggests that the toads perceived this treatment as a stressor. Furthermore, the results also highlight a potential trade-off with performance and reproductive hormones. Ultimately, exposure acute thermal stressors due to climatic variability could impact amphibians at

  16. Acute Thermal Stressor Increases Glucocorticoid Response but Minimizes Testosterone and Locomotor Performance in the Cane Toad (Rhinella marina)

    PubMed Central

    Narayan, Edward J.; Hero, Jean-Marc

    2014-01-01

    Climatic warming is a global problem and acute thermal stressor in particular could be considered as a major stressor for wildlife. Cane toads (Rhinella marina) have expanded their range into warmer regions of Australia and they provide a suitable model species to study the sub-lethal impacts of thermal stressor on the endocrine physiology of amphibians. Presently, there is no information to show that exposure to an acute thermal stressor could initiate a physiological stress (glucocorticoid) response and secondly, the possible effects on reproductive hormones and performance. Answering these questions is important for understanding the impacts of extreme temperature on amphibians. In this study, we experimented on cane toads from Queensland, Australia by acclimating them to mildly warm temperature (25°C) and then exposing to acute temperature treatments of 30°, 35° or 40°C (hypothetical acute thermal stressors). We measured acute changes in the stress hormone corticosterone and the reproductive hormone testosterone using standard capture and handling protocol and quantified the metabolites of both hormones non-invasively using urinary enzyme-immunoassays. Furthermore, we measured performance trait (i.e. righting response score) in the control acclimated and the three treatment groups. Corticosterone stress responses increased in all toads during exposure to an acute thermal stressor. Furthermore, exposure to a thermal stressor also decreased testosterone levels in all toads. The duration of the righting response (seconds) was longer for toads that were exposed to 40°C than to 30°, 35° or 25°C. The increased corticosterone stress response with increased intensity of the acute thermal stressor suggests that the toads perceived this treatment as a stressor. Furthermore, the results also highlight a potential trade-off with performance and reproductive hormones. Ultimately, exposure acute thermal stressors due to climatic variability could impact amphibians at

  17. Acute Restraint Stress Alters Wheel-Running Behavior Immediately Following Stress and up to 20 Hours Later in House Mice.

    PubMed

    Malisch, Jessica L; deWolski, Karen; Meek, Thomas H; Acosta, Wendy; Middleton, Kevin M; Crino, Ondi L; Garland, Theodore

    In vertebrates, acute stressors-although short in duration-can influence physiology and behavior over a longer time course, which might have important ramifications under natural conditions. In laboratory rats, for example, acute stress has been shown to increase anxiogenic behaviors for days after a stressor. In this study, we quantified voluntary wheel-running behavior for 22 h following a restraint stress and glucocorticoid levels 24 h postrestraint. We utilized mice from four replicate lines that have been selectively bred for high voluntary wheel-running activity (HR mice) for 60 generations and their nonselected control (C) lines to examine potential interactions between exercise propensity and sensitivity to stress. Following 6 d of wheel access on a 12L∶12D photo cycle (0700-1900 hours, as during the routine selective breeding protocol), 80 mice were physically restrained for 40 min, beginning at 1400 hours, while another 80 were left undisturbed. Relative to unrestrained mice, wheel running increased for both HR and C mice during the first hour postrestraint (P < 0.0001) but did not differ 2 or 3 h postrestraint. Wheel running was also examined at four distinct phases of the photoperiod. Running in the period of 1600-1840 hours was unaffected by restraint stress and did not differ statistically between HR and C mice. During the period of peak wheel running (1920-0140 hours), restrained mice tended to run fewer revolutions (-11%; two-tailed P = 0.0733), while HR mice ran 473% more than C (P = 0.0008), with no restraint × line type interaction. Wheel running declined for all mice in the latter part of the scotophase (0140-0600 hours), restraint had no statistical effect on wheel running, but HR again ran more than C (+467%; P = 0.0122). Finally, during the start of the photophase (0720-1200 hours), restraint increased running by an average of 53% (P = 0.0443) in both line types, but HR and C mice did not differ statistically. Mice from HR lines had

  18. Conventional and simplified canopy temperature indices predict water stress in sunflower

    USDA-ARS?s Scientific Manuscript database

    Two indicators based on remotely-sensed canopy temperature were used in northern Colorado to monitor water stress in sunflower under six levels of regulated deficit irrigation. The two indicators included the widely-used Crop Water Stress Index (CWSI) and the new Degrees Above Non-stressed Canopy at...

  19. Acute stress symptoms during the second Lebanon war in a random sample of Israeli citizens.

    PubMed

    Cohen, Miri; Yahav, Rivka

    2008-02-01

    The aims of this study were to assess prevalence of acute stress disorder (ASD) and acute stress symptoms (ASS) in Israel during the second Lebanon war. A telephone survey was conducted in July 2006 of a random sample of 235 residents of northern Israel, who were subjected to missile attacks, and of central Israel, who were not subjected to missile attacks. Results indicate that ASS scores were higher in the northern respondents; 6.8% of the northern sample and 3.9% of the central sample met ASD criteria. Appearance of each symptom ranged from 15.4% for dissociative to 88.4% for reexperiencing, with significant differences between northern and central respondents only for reexperiencing and arousal. A low ASD rate and a moderate difference between areas subjected and not subjected to attack were found.

  20. Decreased reaction time variability is associated with greater cardiovascular responses to acute stress

    PubMed Central

    Hamer, Mark; Steptoe, Andrew; Endrighi, Romano

    2016-01-01

    Abstract Cardiovascular (CV) responses to mental stress are prospectively associated with poor CV outcomes. The association between CV responses to mental stress and reaction times (RTs) in aging individuals may be important but warrants further investigation. The present study assessed RTs to examine associations with CV responses to mental stress in healthy, older individuals using robust regression techniques. Participants were 262 men and women (mean age = 63.3 ± 5.5 years) from the Whitehall II cohort who completed a RT task (Stroop) and underwent acute mental stress (mirror tracing) to elicit CV responses. Blood pressure, heart rate, and heart rate variability were measured at baseline, during acute stress, and through a 75‐min recovery. RT measures were generated from an ex‐Gaussian distribution that yielded three predictors: mu‐RT, sigma‐RT, and tau‐RT, the mean, standard deviation, and mean of the exponential component of the normal distribution, respectively. Decreased intraindividual RT variability was marginally associated with greater systolic (B = −.009, SE = .005, p = .09) and diastolic (B = −.004, SE = .002, p = .08) blood pressure reactivity. Decreased intraindividual RT variability was associated with impaired systolic blood pressure recovery (B = −.007, SE = .003, p = .03) and impaired vagal tone (B = −.0047, SE = .0024, p = .045). Study findings offer tentative support for an association between RTs and CV responses. Despite small effect sizes and associations not consistent across predictors, these data may point to a link between intrinsic neuronal plasticity and CV responses. PMID:26894967

  1. Decreased reaction time variability is associated with greater cardiovascular responses to acute stress.

    PubMed

    Wawrzyniak, Andrew J; Hamer, Mark; Steptoe, Andrew; Endrighi, Romano

    2016-05-01

    Cardiovascular (CV) responses to mental stress are prospectively associated with poor CV outcomes. The association between CV responses to mental stress and reaction times (RTs) in aging individuals may be important but warrants further investigation. The present study assessed RTs to examine associations with CV responses to mental stress in healthy, older individuals using robust regression techniques. Participants were 262 men and women (mean age = 63.3 ± 5.5 years) from the Whitehall II cohort who completed a RT task (Stroop) and underwent acute mental stress (mirror tracing) to elicit CV responses. Blood pressure, heart rate, and heart rate variability were measured at baseline, during acute stress, and through a 75-min recovery. RT measures were generated from an ex-Gaussian distribution that yielded three predictors: mu-RT, sigma-RT, and tau-RT, the mean, standard deviation, and mean of the exponential component of the normal distribution, respectively. Decreased intraindividual RT variability was marginally associated with greater systolic (B = -.009, SE = .005, p = .09) and diastolic (B = -.004, SE = .002, p = .08) blood pressure reactivity. Decreased intraindividual RT variability was associated with impaired systolic blood pressure recovery (B = -.007, SE = .003, p = .03) and impaired vagal tone (B = -.0047, SE = .0024, p = .045). Study findings offer tentative support for an association between RTs and CV responses. Despite small effect sizes and associations not consistent across predictors, these data may point to a link between intrinsic neuronal plasticity and CV responses. © 2016 The Authors. Psychophysiology published by Wiley Periodicals, Inc. on behalf of Society for Psychophysiological Research.

  2. A retrospective study of ketamine administration and the development of acute or post-traumatic stress disorder in 274 war-wounded soldiers.

    PubMed

    Mion, G; Le Masson, J; Granier, C; Hoffmann, C

    2017-12-01

    The objective of this study was to explore whether ketamine prevents or exacerbates acute or post-traumatic stress disorders in military trauma patients. We conducted a retrospective study of a database from the French Military Health Service, including all soldiers surviving a war injury in Afghanistan (2010-2012). The diagnosis of post-traumatic stress disorder was made by a psychiatrist and patients were analysed according to the presence or absence of this condition. Analysis included the following covariables: age; sex; acute stress disorder; blast injury; associated fatality; brain injury; traumatic amputation; Glasgow coma scale; injury severity score; administered drugs; number of surgical procedures; physical, neurosensory or aesthetic sequelae; and the development chronic pain. Covariables related to post-traumatic and acute stress disorders with a p ≤ 0.10 were included in a multivariable logistic regression model. The data from 450 soldiers were identified; 399 survived, of which 274 were analysed. Among these, 98 (36%) suffered from post-traumatic stress disorder and 89 (32%) had received ketamine. Fifty-four patients (55%) in the post-traumatic stress disorder group received ketamine vs. 35 (20%) in the no PTSD group (p < 0.001). The 89 injured soldiers who received ketamine had a median (IQR [range]) injury severity score of 5 (3-13 [1-26]) vs. 3 (2-4 [1-6] in the 185 patients who did not (p < 0.001). At multivariable analysis, only acute stress disorder and total number of surgical procedures were independently associated with the development of post-traumatic stress disorder. In this retrospective study, ketamine administration was not a risk factor for the development of post-traumatic stress disorder in the military trauma setting. © 2017 The Association of Anaesthetists of Great Britain and Ireland.

  3. Protective Effect of Thalidomide on Liver Injury in Rats with Acute Pancreatitis via Inhibition of Oxidative Stress.

    PubMed

    Lv, Peng; Fan, Li-Juan; Li, Hong-Yun; Meng, Qing-Shun; Liu, Jie

    2015-01-01

    This study was designed to investigate the preventive effect of thalidomide on acute pancreatitis-associated liver injury in the rat and analyze its relationship with oxidative stress. The acute pancreatitis of rats was induced by the retrograde injection of 5% sodium taurocholate into the biliopancreatic duct. Thalidomide (100 mg/kg) was given daily via the intragastric route for 8 days before this injection. The levels of oxidative stress parameters including superoxide dismutase (SOD), glutathione peroxidase (GSHpx), and malondialdehyde (MDA) in the liver were detected by biochemical assay. Nuclear factor-κB p65 (NF-κBp65), tumor necrosis factor α (TNF-α), and intercellular adhesion molecule-1 (ICAM-1) protein and mRNA levels in the liver were detected using western blots and reverse transcriptase polymerase chain reaction, respectively. Compared with the untreated model group, liver histopathology, SOD, GSHpx, MDA levels, NF-κBp65, TNF-α, ICAM-1 protein, and mRNA levels in the liver of rats given thalidomide were improved significantly. Results demonstrate that thalidomide may exert its effects on oxidative stress to attenuate the progression of acute pancreatitis-associated liver injury in rats. © 2015 by the Association of Clinical Scientists, Inc.

  4. Parent-child agreement regarding children's acute stress: the role of parent acute stress reactions.

    PubMed

    Kassam-Adams, Nancy; García-España, J Felipe; Miller, Victoria A; Winston, Flaura

    2006-12-01

    We examined parent-child agreement regarding child acute stress disorder (ASD) and the relationship between parent ASD symptoms and parent ratings of child ASD. Parent-child dyads (N = 219; child age 8-17 years) were assessed within 1 month of child injury. Parent-child agreement was examined regarding child ASD presence, severity, and specific symptoms. Relationships among parent ASD and parent- and child-reported child ASD were examined using regression analysis and generalized estimating equations (GEE). Parent-child agreement was low for presence of child ASD (kappa = 0.22) and for individual symptoms. Parent and child ratings of child ASD severity were moderately correlated (r = 0.35). Parent ASD was independently associated with parent-rated child ASD, after accounting for child self-rating (beta =.65). Generalized estimating equations indicated that parents with ASD overestimated child ASD and parents without ASD underestimated child ASD, compared to the child's self-rating. Parents' own responses to a potentially traumatic event appear to influence their assessment of child symptoms. Clinicians should obtain child self-report of ASD whenever possible and take parent symptoms into account when interpreting parent reports. Helping parents to assess a child's needs following a potentially traumatic event may be a relevant target for clinical attention.

  5. Analysis of Biaxial Stress Fields in Plates Cracking at Elevated Temperatures

    DTIC Science & Technology

    1989-10-19

    used . Based on the enhanced theory, it is predicted that the minimum resolvable stress amplitude using thermographic stress analysis will be...because of limitations in the commercial thermographic equipment used . Based on the enhanced theory, it is predicted that the minimum resolvable stress...amplitude using thermographic stress analysis will be approximately independent of temperature, provided relevant thermal and mechanical material

  6. Acute effects of coffee consumption on self-reported gastrointestinal symptoms, blood pressure and stress indices in healthy individuals.

    PubMed

    Papakonstantinou, Emilia; Kechribari, Ioanna; Sotirakoglou, Κyriaki; Tarantilis, Petros; Gourdomichali, Theodora; Michas, George; Kravvariti, Vassiliki; Voumvourakis, Konstantinos; Zampelas, Antonis

    2016-03-15

    It has been suggested that coffee may affect the gut-brain axis with conflicting outcomes. Moreover, there is insufficient evidence to determine whether the type or temperature of coffee consumed will have a different impact on the gut-brain axis. The purpose of this study was to investigate the effects of acute coffee consumption on the following: 1. self-reported GI symptoms and salivary gastrin, 2. stress indices [salivary cortisol and alpha-amylase (sAA)] and psychometric measures, and 3. blood pressure (BP), in healthy, daily coffee consuming individuals in non-stressful conditions. This was a randomized, double blind, crossover clinical trial, in which 40 healthy individuals (20 men, 20 women), 20-55 years of age, randomly consumed four 200 ml coffee beverages containing 160 mg caffeine (hot and cold instant coffee, cold espresso, hot filtered coffee), 1 week apart. Salivary samples and psychometric questionnaires were collected at baseline and post-coffee consumption at 15,30, and 60 min for salivary gastrin and sAA measurements and at 60,120, and 180 min for cortisol measurements. BP was measured at beginning and end of each intervention. ClinicalTrials.gov ID: NCT02253628 RESULTS: Coffee consumption significantly increased sAA activity (P = 0.041), with significant differences only between cold instant and filter coffee at 15 and 30 min post-consumption (P < 0.05). Coffee temporarily increased salivary gastrin, without differences between coffee types. Coffee did not affect salivary cortisol or self-reported anxiety levels. Coffee consumption significantly increased BP, within the healthy physiological levels, in a gender specific manner at the end of the experimental periods, without differences between coffee types. Acute coffee consumption in non-stressful conditions activated sAA and BP but not salivary cortisol, indicating activation of the sympathetic nervous system. Post-coffee sAA increase without a concomitant cortisol increase may also indicate

  7. Acute Stress-Induced Epigenetic Modulations and Their Potential Protective Role Toward Depression.

    PubMed

    Rusconi, Francesco; Battaglioli, Elena

    2018-01-01

    Psychiatric disorders entail maladaptive processes impairing individuals' ability to appropriately interface with environment. Among them, depression is characterized by diverse debilitating symptoms including hopelessness and anhedonia, dramatically impacting the propensity to live a social and active life and seriously affecting working capability. Relevantly, besides genetic predisposition, foremost risk factors are stress-related, such as experiencing chronic psychosocial stress-including bullying, mobbing and abuse-, and undergoing economic crisis or chronic illnesses. In the last few years the field of epigenetics promised to understand core mechanisms of gene-environment crosstalk, contributing to get into pathogenic processes of many disorders highly influenced by stressful life conditions. However, still very little is known about mechanisms that tune gene expression to adapt to the external milieu. In this Perspective article, we discuss a set of protective, functionally convergent epigenetic processes induced by acute stress in the rodent hippocampus and devoted to the negative modulation of stress-induced immediate early genes (IEGs) transcription, hindering stress-driven morphostructural modifications of corticolimbic circuitry. We also suggest that chronic stress damaging protective epigenetic mechanisms, could bias the functional trajectory of stress-induced neuronal morphostructural modification from adaptive to maladaptive, contributing to the onset of depression in vulnerable individuals. A better understanding of the epigenetic response to stress will be pivotal to new avenues of therapeutic intervention to treat depression, especially in light of limited efficacy of available antidepressant drugs.

  8. The effects of acute stress on performance: implications for health professions education.

    PubMed

    LeBlanc, Vicki R

    2009-10-01

    This paper is a review of representative research on the impact of acute stressors on the clinical performance of individuals and teams. The Sciences Citation Index, Medline, and Psychinfo were used to search for articles up to and including 2008. The search terms were stress/tension/arousal/anxiety/cortisol/threat, cognition/skills/memory/attention/problem solving/decision making/performance, stress reduction/stress exposure/stress management/stress inoculation, and health professionals/medicine/medical students/residents/physicians/teams. The search was limited to papers in English from all developed countries. Secondary references were selected from primary papers. Elevated stress levels can impede performance on tasks that require divided attention, working memory, retrieval of information from memory, and decision making. These effects appear to be determined by the individual's appraisal of the demands and resources of a situation, the relationship between the stressor and the task, and factors such as coping styles, locus of control, and social supports. Given the potential negative impact of stress on performance, and the individualistic way in which people respond, medical educators might want to consider avenues for training learners in stress management. More research is needed to fully understand the contributions of personal factors such as coping style and locus of control, as well as the relationship of perceptions of stress to issues such as fatigue.

  9. Effects of temperature and cadmium exposure on the mitochondria of oysters (Crassostrea virginica) exposed to hypoxia and subsequent reoxygenation.

    PubMed

    Ivanina, Anna V; Kurochkin, Ilya O; Leamy, Larry; Sokolova, Inna M

    2012-09-15

    Intertidal bivalves are commonly exposed to multiple stressors including periodic hypoxia, temperature fluctuations and pollution, which can strongly affect energy metabolism. We used top-down control and elasticity analyses to determine the interactive effects of intermittent hypoxia, cadmium (Cd) exposure and acute temperature stress on mitochondria of the eastern oyster Crassostrea virginica. Oysters were acclimated at 20°C for 30 days in the absence or presence of 50 μg l(-1) Cd and then subjected to a long-term hypoxia (6 days at <0.5% O(2) in seawater) followed by normoxic recovery. Mitochondrial function was assessed at the acclimation temperature (20°C), or at elevated temperature (30°C) mimicking acute temperature stress in the intertidal zone. In the absence of Cd or temperature stress, mitochondria of oysters showed high resilience to transient hypoxia. In control oysters at 20°C, hypoxia/reoxygenation induced elevated flux capacity of all three studied mitochondrial subsystems (substrate oxidation, phosphorylation and proton leak) and resulted in a mild depolarization of resting mitochondria. Elevated proton conductance and enhanced capacity of phosphorylation and substrate oxidation subsystems may confer resistance to hypoxia/reoxygenation stress in oyster mitochondria by alleviating production of reactive oxygen species and maintaining high aerobic capacity and ATP synthesis rates during recovery. Exposure to environmental stressors such as Cd and elevated temperatures abolished the putative adaptive responses of the substrate oxidation and phosphorylation subsystems, and strongly enhanced proton leak in mitochondria of oysters subjected to hypoxia/reoxygenation stress. Our findings suggest that Cd exposure and acute temperature stress may lead to the loss of mitochondrial resistance to hypoxia and reoxygenation and thus potentially affect the ability of oysters to survive periodic oxygen deprivation in coastal and estuarine habitats.

  10. Proteomic changes in rice leaves grown under open field high temperature stress conditions.

    PubMed

    Das, Smruti; Krishnan, P; Mishra, Vagish; Kumar, Ritesh; Ramakrishnan, B; Singh, N K

    2015-11-01

    The interactive effect of temperature with other climatic and soil factors has profound influences on the growth and development of rice. The responses of rice to high temperatures under field conditions are more important than those under the controlled conditions. To understand the genes associated with high temperature stress response in general and tolerance in particular, the expression of all those genes associated with adaptation and tolerance in rice requires proteomic analysis. High temperature stress-tolerant cv. N22 was subjected to 28/18 °C (control) and 42/32 °C (high temperature stress) at flowering stage. The plants were grown in the field under the free air temperature increment condition. The proteomic changes in rice leaves due to high temperature stress were discussed. The proteomes of leaves had about 3000 protein spots, reproducibly detected on 2-dimensional electrophoretic gels with 573 proteins differentially expressed between the control and the high temperature treatments. Putative physiological functions suggested five categories such as growth (15.4%), heat shock proteins (7.7%), regulatory proteins (26.9%), redox homeostasis proteins (11.5%) and energy and metabolism (38.5%) related proteins. The results of the present study suggest that cv. N22, an agronomically recognized temperature tolerant rice cultivar copes with high temperature stress in a complex manner. Several functional proteins play important roles in its responses. The predicted climate change events necessitate more studies using this cultivar under different simulated ecological conditions to identify proteomic changes and the associated genes to be used as biomarkers and to gain a better understanding on the biochemical pathways involved in tolerance.

  11. Influence of temperature on acid-stress adaptation in Listeria monocytogenes

    USDA-ARS?s Scientific Manuscript database

    Several factors play critical roles in controlling the induction of acid-stress adaptation in L. monocytogenes. Our findings show that temperature plays a significant role in the induction of acid-stress adaptation in Listeria monocytogenes and two distinct patterns were observed: (I) Presence of su...

  12. The response of a boreal deep-sea sponge holobiont to acute thermal stress.

    PubMed

    Strand, R; Whalan, S; Webster, N S; Kutti, T; Fang, J K H; Luter, H M; Bannister, R J

    2017-05-22

    Effects of elevated seawater temperatures on deep-water benthos has been poorly studied, despite reports of increased seawater temperature (up to 4 °C over 24 hrs) coinciding with mass mortality events of the sponge Geodia barretti at Tisler Reef, Norway. While the mechanisms driving these mortality events are unclear, manipulative laboratory experiments were conducted to quantify the effects of elevated temperature (up to 5 °C, above ambient levels) on the ecophysiology (respiration rate, nutrient uptake, cellular integrity and sponge microbiome) of G. barretti. No visible signs of stress (tissue necrosis or discolouration) were evident across experimental treatments; however, significant interactive effects of time and treatment on respiration, nutrient production and cellular stress were detected. Respiration rates and nitrogen effluxes doubled in responses to elevated temperatures (11 °C & 12 °C) compared to control temperatures (7 °C). Cellular stress, as measured through lysosomal destabilisation, was 2-5 times higher at elevated temperatures than for control temperatures. However, the microbiome of G. barretti remained stable throughout the experiment, irrespective of temperature treatment. Mortality was not evident and respiration rates returned to pre-experimental levels during recovery. These results suggest other environmental processes, either alone or in combination with elevated temperature, contributed to the mortality of G. barretti at Tisler reef.

  13. Thermal Stress FE Analysis of Large-scale Gas Holder Under Sunshine Temperature Field

    NASA Astrophysics Data System (ADS)

    Li, Jingyu; Yang, Ranxia; Wang, Hehui

    2018-03-01

    The temperature field and thermal stress of Man type gas holder is simulated by using the theory of sunshine temperature field based on ASHRAE clear-sky model and the finite element method. The distribution of surface temperature and thermal stress of gas holder under the given sunshine condition is obtained. The results show that the thermal stress caused by sunshine can be identified as one of the important factors for the failure of local cracked oil leakage which happens on the sunny side before on the shady side. Therefore, it is of great importance to consider the sunshine thermal load in the stress analysis, design and operation of large-scale steel structures such as the gas holder.

  14. [Exercise stress test and dobutamine stress echocardiography for the prognostic stratification after uncomplicated acute myocardial infarction].

    PubMed

    Vitiello, Nicola; Cirillo, Raffaele; Granato, Luigi; Coppola, Vincenzo; di Palma, Francesco

    2007-05-01

    Exercise stress test and dobutamine stress echocardiography are usually performed early after an uncomplicated acute myocardial infarction in the prognostic stratification of patients to define the optimal diagnostic and therapeutic procedure. The aim of this study was to evaluate if the association of an imaging test could increase exercise test capability to identify patients with residual ischemia and patients at high risk of events in the follow-up. Four hundred and forty-two consecutive patients underwent exercise stress testing and dobutamine stress echocardiography before discharge and subsequently coronary angiography within 30 days. In case of submaximal negative result at the exercise test, this was repeated 20 days after discharge. The follow-up lasted 26.8 +/- 9 months. The endpoints were death, reinfarction, and unstable angina requiring hospitalization or revascularization intervention. Both tests and their association showed a higher sensitivity in males; in females dobutamine stress echocardiography had a higher specificity. In females, the addition of dobutamine stress echocardiography increased either the negative or the positive prognostic values of exercise stress test by 31% and 5.6%, respectively. In males, the negative prognostic value increased by 15.5%, whereas the positive prognostic value decreased by 12%. A low exercise capability (<6 METs) showed an event predictive value independent of test results and any other variables. The event-free survival curves correlated with exercise capability differed shortly after the first months both in males and females. These results suggest different stratification procedures with regard to gender: in males, the exercise stress test might be sufficient at discharge, to be repeated 20 days later, if submaximal negative. In females, it seems to be useful to associate an imaging test at discharge. In any case, the exercise stress test remains the main step in the stratification procedure also for its

  15. Interaction of Osmotic Stress, Temperature, and Abscisic Acid in the Regulation of Gene Expression in Arabidopsis

    PubMed Central

    Xiong, Liming; Ishitani, Manabu; Zhu, Jian-Kang

    1999-01-01

    The impact of simultaneous environmental stresses on plants and how they respond to combined stresses compared with single stresses is largely unclear. By using a transgene (RD29A-LUC) consisting of the firefly luciferase coding sequence (LUC) driven by the stress-responsive RD29A promoter, we investigated the interactive effects of temperature, osmotic stress, and the phytohormone abscisic acid (ABA) in the regulation of gene expression in Arabidopsis seedlings. Results indicated that both positive and negative interactions exist among the studied stress factors in regulating gene expression. At a normal growth temperature (22°C), osmotic stress and ABA act synergistically to induce the transgene expression. Low temperature inhibits the response to osmotic stress or to combined treatment of osmotic stress and ABA, whereas low temperature and ABA treatments are additive in inducing transgene expression. Although high temperature alone does not activate the transgene, it significantly amplifies the effects of ABA and osmotic stress. The effect of multiple stresses in the regulation of RD29A-LUC expression in signal transduction mutants was also studied. The results are discussed in the context of cold and osmotic stress signal transduction pathways. PMID:9880362

  16. Serum Response Factor (SRF) Ablation Interferes with Acute Stress-Associated Immediate and Long-Term Coping Mechanisms.

    PubMed

    Zimprich, Annemarie; Mroz, Gabi; Meyer Zu Reckendorf, Christopher; Anastasiadou, Sofia; Förstner, Philip; Garrett, Lillian; Hölter, Sabine M; Becker, Lore; Rozman, Jan; Prehn, Cornelia; Rathkolb, Birgit; Moreth, Kristin; Wurst, Wolfgang; Klopstock, Thomas; Klingenspor, Martin; Adamski, Jerzy; Wolf, Eckhard; Bekeredjian, Raffi; Fuchs, Helmut; Gailus-Durner, Valerie; de Angelis, Martin Hrabe; Knöll, Bernd

    2017-12-01

    Stress experience modulates behavior, metabolism, and energy expenditure of organisms. One molecular hallmark of an acute stress response is a rapid induction of immediate early genes (IEGs) such as c-Fos and Egr family members. IEG transcription in neurons is mediated by the neuronal activity-driven gene regulator serum response factor (SRF). We show a first role of SRF in immediate and long-lasting acute restraint stress (AS) responses. For this, we employed a standardized mouse phenotyping protocol at the German Mouse Clinic (GMC) including behavioral, metabolic, and cardiologic tests as well as gene expression profiling to analyze the consequences of forebrain-specific SRF deletion in mice exposed to AS. Adult mice with an SRF deletion in glutamatergic neurons (Srf; CaMKIIa-CreERT2 ) showed hyperactivity, decreased anxiety, and impaired working memory. In response to restraint AS, instant stress reactivity including locomotor behavior and corticosterone induction was impaired in Srf mutant mice. Interestingly, even several weeks after previous AS exposure, SRF-deficient mice showed long-lasting AS-associated changes including altered locomotion, metabolism, energy expenditure, and cardiovascular changes. This suggests a requirement of SRF for mediating long-term stress coping mechanisms in wild-type mice. SRF ablation decreased AS-mediated IEG induction and activity of the actin severing protein cofilin. In summary, our data suggest an SRF function in immediate AS reactions and long-term post-stress-associated coping mechanisms.

  17. Ventral tegmental area dopamine revisited: effects of acute and repeated stress

    PubMed Central

    Holly, Elizabeth N.; Miczek, Klaus A.

    2015-01-01

    Aversive events rapidly and potently excite certain dopamine neurons in the ventral tegmental area (VTA), promoting phasic increases in the medial prefrontal cortex and nucleus accumbens. This is in apparent contradiction to a wealth of literature demonstrating that most VTA dopamine neurons are strongly activated by reward and reward-predictive cues while inhibited by aversive stimuli. How can these divergent processes both be mediated by VTA dopamine neurons? The answer may lie within the functional and anatomical heterogeneity of the VTA. We focus on VTA heterogeneity in anatomy, neurochemistry, electrophysiology, and afferent/efferent connectivity. Second, recent evidence for a critical role of VTA dopamine neurons in response to both acute and repeated stress will be discussed. Understanding which dopamine neurons are activated by stress, the neural mechanisms driving the activation, and where these neurons project will provide valuable insight into how stress can promote psychiatric disorders associated with the dopamine system, such as addiction and depression. PMID:26676983

  18. Temperature and blood flow distribution in the human leg during passive heat stress

    PubMed Central

    Chiesa, Scott T.; Trangmar, Steven J.

    2016-01-01

    The influence of temperature on the hemodynamic adjustments to direct passive heat stress within the leg's major arterial and venous vessels and compartments remains unclear. Fifteen healthy young males were tested during exposure to either passive whole body heat stress to levels approaching thermal tolerance [core temperature (Tc) + 2°C; study 1; n = 8] or single leg heat stress (Tc + 0°C; study 2; n = 7). Whole body heat stress increased perfusion and decreased oscillatory shear index in relation to the rise in leg temperature (Tleg) in all three major arteries supplying the leg, plateauing in the common and superficial femoral arteries before reaching severe heat stress levels. Isolated leg heat stress increased arterial blood flows and shear patterns to a level similar to that obtained during moderate core hyperthermia (Tc + 1°C). Despite modest increases in great saphenous venous (GSV) blood flow (0.2 l/min), the deep venous system accounted for the majority of returning flow (common femoral vein 0.7 l/min) during intense to severe levels of heat stress. Rapid cooling of a single leg during severe whole body heat stress resulted in an equivalent blood flow reduction in the major artery supplying the thigh deep tissues only, suggesting central temperature-sensitive mechanisms contribute to skin blood flow alone. These findings further our knowledge of leg hemodynamic responses during direct heat stress and provide evidence of potentially beneficial vascular alterations during isolated limb heat stress that are equivalent to those experienced during exposure to moderate levels of whole body hyperthermia. PMID:26823344

  19. Roles of p75NTR, long-term depression and cholinergic transmission in anxiety and acute stress coping

    PubMed Central

    Martinowich, Keri; Schloesser, Robert J.; Lu, Yuan; Jimenez, Dennisse V.; Paredes, Daniel; Greene, Joshua S.; Greig, Nigel H.; Manji, Husseini K.; Lu, Bai

    2011-01-01

    Background Stress is causally associated with anxiety. While the underlying cellular mechanisms are not well understood, the basal forebrain cholinergic neurons (BFCNs) have been implicated in stress response. p75NTR is a pan-neurotrophin receptor expressed almost exclusively in BFCNs in adult brain. The present study investigates whether and how p75NTR, via regulation of the cholinergic system and hippocampal synaptic plasticity, influences stress-related behaviors. Methods We used a combination of slice electrophysiology, behavioral analyses, pharmacology, in vivo microdialysis and neuronal activity mapping to assess the role of p75NTR in mood and stress-related behaviors and its underlying cellular and molecular mechanisms. Results We show that acute stress enables hippocampal long-term depression (LTD) in adult wild-type mice, but not in mice lacking p75NTR. The p75NTR mutant mice also exhibit two distinct behavioral impairments: baseline anxiety-like behavior and a deficit in coping with and recovering from stressful situations. Blockade of stress-enabled LTD with a GluA2-derived peptide impaired stress recovery without affecting baseline anxiety. Pharmacological manipulations of cholinergic transmission mimicked the p75NTR perturbation in both baseline anxiety and responses to acute stress. Finally, we show evidence of misregulated cholinergic signaling in animals with p75NTR deletion. Conclusions Our results suggest that loss of p75NTR leads to changes in hippocampal cholinergic signaling, which may be involved in regulation of stress-enabled hippocampal LTD and in modulating behaviors related to stress and anxiety. PMID:21978521

  20. Impact of high temperature stress on floret fertility and individual grain weight of grain sorghum: sensitive stages and thresholds for temperature and duration

    PubMed Central

    Prasad, P. V. V.; Djanaguiraman, Maduraimuthu; Perumal, Ramasamy; Ciampitti, Ignacio A.

    2015-01-01

    Sorghum [Sorghum bicolor (L.) Moench] yield formation is severely affected by high temperature stress during reproductive stages. This study pursues to (i) identify the growth stage(s) most sensitive to high temperature stress during reproductive development, (ii) determine threshold temperature and duration of high temperature stress that decreases floret fertility and individual grain weight, and (iii) quantify impact of high daytime temperature during floret development, flowering and grain filling on reproductive traits and grain yield under field conditions. Periods between 10 and 5 d before anthesis; and between 5 d before- and 5 d after-anthesis were most sensitive to high temperatures causing maximum decreases in floret fertility. Mean daily temperatures >25°C quadratically decreased floret fertility (reaching 0% at 37°C) when imposed at the start of panicle emergence. Temperatures ranging from 25 to 37°C quadratically decreased individual grain weight when imposed at the start of grain filling. Both floret fertility and individual grain weights decreased quadratically with increasing duration (0–35 d or 49 d during floret development or grain filling stage, respectively) of high temperature stress. In field conditions, imposition of temperature stress (using heat tents) during floret development or grain filling stage also decreased floret fertility, individual grain weight, and grain weight per panicle. PMID:26500664

  1. Effects of stress ratio on the temperature-dependent high-cycle fatigue properties of alloy steels

    NASA Astrophysics Data System (ADS)

    Lü, Zhi-yang; Wan, Ao-shuang; Xiong, Jun-jiang; Li, Kuang; Liu, Jian-zhong

    2016-12-01

    This paper addresses the effects of stress ratio on the temperature-dependent high-cycle fatigue (HCF) properties of alloy steels 2CrMo and 9CrCo, which suffer from substantial vibrational loading at small stress amplitude, high stress ratio, and high frequency in the high-temperature environments in which they function as blade and rotor spindle materials in advanced gas or steam turbine engines. Fatigue tests were performed on alloy steels 2CrMo and 9CrCo subjected to constant-amplitude loading at four stress ratios and at four and three temperatures, respectively, to determine their temperature-dependent HCF properties. The interaction mechanisms between high temperature and stress ratio were deduced and compared with each other on the basis of the results of fractographic analysis. A phenomenological model was developed to evaluate the effects of stress ratio on the temperature-dependent HCF properties of alloy steels 2CrMo and 9CrCo. Good correlation was achieved between the predictions and actual experiments, demonstrating the practical and effective use of the proposed method.

  2. Critical features of acute stress-induced cross-sensitization identified through the hypothalamic-pituitary-adrenal axis output.

    PubMed

    Belda, Xavier; Nadal, Roser; Armario, Antonio

    2016-08-11

    Stress-induced sensitization represents a process whereby prior exposure to severe stressors leaves animals or humans in a hyper-responsive state to further stressors. Indeed, this phenomenon is assumed to be the basis of certain stress-associated pathologies, including post-traumatic stress disorder and psychosis. One biological system particularly prone to sensitization is the hypothalamic-pituitary-adrenal (HPA) axis, the prototypic stress system. It is well established that under certain conditions, prior exposure of animals to acute and chronic (triggering) stressors enhances HPA responses to novel (heterotypic) stressors on subsequent days (e.g. raised plasma ACTH and corticosterone levels). However, such changes remain somewhat controversial and thus, the present study aimed to identify the critical characteristics of the triggering and challenging stressors that affect acute stress-induced HPA cross-sensitization in adult rats. We found that HPA cross-sensitization is markedly influenced by the intensity of the triggering stressor, whereas the length of exposure mainly affects its persistence. Importantly, HPA sensitization is more evident with mild than strong challenging stressors, and it may remain unnoticed if exposure to the challenging stressor is prolonged beyond 15 min. We speculate that heterotypic HPA sensitization might have developed to optimize biologically adaptive responses to further brief stressors.

  3. Critical features of acute stress-induced cross-sensitization identified through the hypothalamic-pituitary-adrenal axis output

    PubMed Central

    Belda, Xavier; Nadal, Roser; Armario, Antonio

    2016-01-01

    Stress-induced sensitization represents a process whereby prior exposure to severe stressors leaves animals or humans in a hyper-responsive state to further stressors. Indeed, this phenomenon is assumed to be the basis of certain stress-associated pathologies, including post-traumatic stress disorder and psychosis. One biological system particularly prone to sensitization is the hypothalamic-pituitary-adrenal (HPA) axis, the prototypic stress system. It is well established that under certain conditions, prior exposure of animals to acute and chronic (triggering) stressors enhances HPA responses to novel (heterotypic) stressors on subsequent days (e.g. raised plasma ACTH and corticosterone levels). However, such changes remain somewhat controversial and thus, the present study aimed to identify the critical characteristics of the triggering and challenging stressors that affect acute stress-induced HPA cross-sensitization in adult rats. We found that HPA cross-sensitization is markedly influenced by the intensity of the triggering stressor, whereas the length of exposure mainly affects its persistence. Importantly, HPA sensitization is more evident with mild than strong challenging stressors, and it may remain unnoticed if exposure to the challenging stressor is prolonged beyond 15 min. We speculate that heterotypic HPA sensitization might have developed to optimize biologically adaptive responses to further brief stressors. PMID:27511270

  4. Internal stress-induced melting below melting temperature at high-rate laser heating

    NASA Astrophysics Data System (ADS)

    Hwang, Yong Seok; Levitas, Valery I.

    2014-06-01

    In this Letter, continuum thermodynamic and phase field approaches (PFAs) predicted internal stress-induced reduction in melting temperature for laser-irradiated heating of a nanolayer. Internal stresses appear due to thermal strain under constrained conditions and completely relax during melting, producing an additional thermodynamic driving force for melting. Thermodynamic melting temperature for Al reduces from 933.67 K for a stress-free condition down to 898.1 K for uniaxial strain and to 920.8 K for plane strain. Our PFA simulations demonstrated barrierless surface-induced melt nucleation below these temperatures and propagation of two solid-melt interfaces toward each other at the temperatures very close to the corresponding predicted thermodynamic equilibrium temperatures for the heating rate Q ≤1.51×1010K/s. At higher heating rates, kinetic superheating competes with a reduction in melting temperature and melting under uniaxial strain occurs at 902.1 K for Q = 1.51 × 1011 K/s and 936.9 K for Q = 1.46 × 1012 K/s.

  5. Temperature and Oxidative Stress as Triggers for Virulence Gene Expression in Pathogenic Leptospira spp.

    PubMed Central

    Fraser, Tricia; Brown, Paul D.

    2017-01-01

    Leptospirosis is a zooanthroponosis aetiologically caused by pathogenic bacteria belonging to the genus, Leptospira. Environmental signals such as increases in temperatures or oxidative stress can trigger response regulatory modes of virulence genes during infection. This study sought to determine the effect of temperature and oxidative stress on virulence associated genes in highly passaged Leptospira borgpeterseneii Jules and L. interrogans Portlandvere. Bacteria were grown in EMJH at 30°C, 37°C, or at 30°C before being transferred to 37°C. A total of 14 virulence-associated genes (fliY, invA, lenA, ligB, lipL32, lipL36, lipL41, lipL45, loa22, lsa21, mce, ompL1, sph2, and tlyC) were assessed using endpoint PCR. Transcriptional analyses of lenA, lipL32, lipL41, loa22, sph2 were assessed by quantitative real-time RT-PCR at the temperature conditions. To assess oxidative stress, bacteria were exposed to H2O2 for 30 and 60 min with or without the temperature stress. All genes except ligB (for Portlandvere) and ligB and mce (for Jules) were detectable in the strains. Quantitatively, temperature stress resulted in significant changes in gene expression within species or between species. Temperature changes were more influential in gene expression for Jules, particularly at 30°C and upshift conditions; at 37°C, expression levels were higher for Portlandvere. However, compared to Jules, where temperature was influential in two of five genes, temperature was an essential element in four of five genes in Portlandvere exposed to oxidative stress. At both low and high oxidative stress levels, the interplay between genetic predisposition (larger genome size) and temperature was biased towards Portlandvere particularly at 30°C and upshift conditions. While it is clear that expression of many virulence genes in highly passaged strains of Leptospira are attenuated or lost, genetic predisposition, changes in growth temperature and/or oxidative intensity and/or duration

  6. Thermal stress in high temperature cylindrical fasteners

    NASA Technical Reports Server (NTRS)

    Blosser, Max L.

    1988-01-01

    Uninsulated structures fabricated from carbon or silicon-based materials, which are allowed to become hot during flight, are attractive for the design of some components of hypersonic vehicles. They have the potential to reduce weight and increase vehicle efficiency. Because of manufacturing contraints, these structures will consist of parts which must be fastened together. The thermal expansion mismatch between conventional metal fasteners and carbon or silicon-based structural materials may make it difficult to design a structural joint which is tight over the operational temperature range without exceeding allowable stress limits. In this study, algebraic, closed-form solutions for calculating the thermal stresses resulting from radial thermal expansion mismatch around a cylindrical fastener are developed. These solutions permit a designer to quickly evaluate many combinations of materials for the fastener and the structure. Using the algebraic equations developed, material properties and joint geometry were varied to determine their effect on thermal stresses. Finite element analyses were used to verify that the closed-form solutions derived give the correct thermal stress distribution around a cylindrical fastener and to investigate the effect of some of the simplifying assumptions made in developing the closed-form solutions for thermal stresses.

  7. Stress Free Temperature Testing and Residual Stress Calculations on Out-of-Autoclave Composites

    NASA Technical Reports Server (NTRS)

    Cox, Sarah; Tate, LaNetra C.; Danley, Susan; Sampson, Jeff; Taylor, Brian; Miller, Sandi

    2012-01-01

    Future launch vehicles will require the incorporation large composite parts that will make up primary and secondary components of the vehicle. NASA has explored the feasibility of manufacturing these large components using Out-of-Autoclave impregnated carbon fiber composite systems through many composites development projects. Most recently, the Composites for Exploration Project has been looking at the development of a 10 meter diameter fairing structure, similar in size to what will be required for a heavy launch vehicle. The development of new material systems requires the investigation of the material properties and the stress in the parts. Residual stress is an important factor to incorporate when modeling the stresses that a part is undergoing. Testing was performed to verify the stress free temperature with two-ply asymmetric panels. A comparison was done between three newly developed out of autoclave IM7 /Bismalieimide (BMI) systems. This paper presents the testing results and the analysis performed to determine the residual stress of the materials.

  8. Stress-induced cardiomyopathy caused by heat stroke.

    PubMed

    Chen, Wei-Ta; Lin, Cheng-Hsin; Hsieh, Ming-Hsiung; Huang, Chun-Yao; Yeh, Jong-Shiuan

    2012-07-01

    Heat stroke is defined by central nervous system abnormalities and failure of proper maintenance of thermoregulation as a result of high core body temperature ensuing from exposure to high environmental temperatures or strenuous exercise. Common complications include acute respiratory distress syndrome, disseminated intravascular coagulation, acute renal injury, hepatic injury, and rhabdomyolysis. Myocardial injury may also occur during heat stroke, resulting in cardiac enzyme increase and ST-segment changes on the ECG. Such findings might behave as diagnostic pitfalls by mimicking the presentation of coronary artery occlusive myocardial infarction. A previous case report described a patient with heat stroke and ST-segment elevation, in which the definite cause of the ST-segment elevation was unclear; however, acute myocardial infarction caused by coronary artery disease was ruled out according to the clinical signs, serial ECG changes, and serum level of cardiac biomarkers. Stress-induced cardiomyopathy (Takotsubo cardiomyopathy) was suspected, but it could not be confirmed because of the lack of coronary angiography. We herein report a case of heat stroke presenting with ST-segment elevation and cardiogenic shock. Coronary angiography was performed and coronary artery occlusive myocardial infarction was ruled out because of the presence of patent coronary arteries. Left ventriculography showed midventricular and apical hypokinesis, and stress-induced cardiomyopathy was then determined to be the appropriate diagnosis. Heat stroke causes increase of serum catecholamine levels, in which oversecretion and abnormal responses to catecholamines are a possible cause of stress-induced cardiomyopathy. Catecholamines may therefore be the key in linking heat stroke and stress-induced cardiomyopathy. Copyright © 2011. Published by Mosby, Inc.

  9. Prickly Pear Cactus (Opuntia ficus indica var. saboten) Protects Against Stress-Induced Acute Gastric Lesions in Rats

    PubMed Central

    Kim, Seung Hyun; Jeon, Byung Ju; Kim, Dae Hyun; Kim, Tae Il; Lee, Hee Kyoung; Han, Dae Seob; Lee, Jong-Hwan; Kim, Tae Bum; Kim, Jung Wha

    2012-01-01

    Abstract The protective activity of prickly pear cactus (Opuntia ficus indica var. saboten) fruit juice and its main constituent, betanin, were evaluated against stress-induced acute gastric lesions in rats. After 6 h of water immersion restraint stress (WIRS), gastric mucosal lesions with bleeding were induced in Sprague–Dawley rats. Pretreatment of a lyophilized powder containing O. ficus indica var. saboten fruit juice and maltodextrin (OFSM) and betanin significantly reduced stress lesions (800–1600 mg/kg). Both OFSM and betanin effectively prevented the decrease in gastric mucus content as detected by alcian blue staining. In addition, OFSM significantly suppressed WIRS-induced increases in the level of gastric mucosal tumor necrosis factor-α and myeloperoxidase (MPO). Betanin alone was only effective in decreasing MPO. These results revealed the protective activity of OFSM against stress-induced acute gastric lesions and that betanin may contribute to OFSM's gastric protective activity, at least in part. When OFSM and betanin were taken together, OFSM exerted gastroprotective activity against stress-induced gastric lesions by maintaining gastric mucus, which might be related to the attenuation of MPO-mediated damage and proinflammatory cytokine production. PMID:23062184

  10. Prickly pear cactus (Opuntia ficus indica var. saboten) protects against stress-induced acute gastric lesions in rats.

    PubMed

    Kim, Seung Hyun; Jeon, Byung Ju; Kim, Dae Hyun; Kim, Tae Il; Lee, Hee Kyoung; Han, Dae Seob; Lee, Jong-Hwan; Kim, Tae Bum; Kim, Jung Wha; Sung, Sang Hyun

    2012-11-01

    The protective activity of prickly pear cactus (Opuntia ficus indica var. saboten) fruit juice and its main constituent, betanin, were evaluated against stress-induced acute gastric lesions in rats. After 6 h of water immersion restraint stress (WIRS), gastric mucosal lesions with bleeding were induced in Sprague-Dawley rats. Pretreatment of a lyophilized powder containing O. ficus indica var. saboten fruit juice and maltodextrin (OFSM) and betanin significantly reduced stress lesions (800-1600 mg/kg). Both OFSM and betanin effectively prevented the decrease in gastric mucus content as detected by alcian blue staining. In addition, OFSM significantly suppressed WIRS-induced increases in the level of gastric mucosal tumor necrosis factor-α and myeloperoxidase (MPO). Betanin alone was only effective in decreasing MPO. These results revealed the protective activity of OFSM against stress-induced acute gastric lesions and that betanin may contribute to OFSM's gastric protective activity, at least in part. When OFSM and betanin were taken together, OFSM exerted gastroprotective activity against stress-induced gastric lesions by maintaining gastric mucus, which might be related to the attenuation of MPO-mediated damage and proinflammatory cytokine production.

  11. The impact of acute stress on the neural processing of food cues in bulimia nervosa: Replication in two samples.

    PubMed

    Collins, Brittany; Breithaupt, Lauren; McDowell, Jennifer E; Miller, L Stephen; Thompson, James; Fischer, Sarah

    2017-07-01

    The impact of acute stress on the neural processing of food cues in bulimia nervosa (BN) is unknown, despite theory that acute stress decreases cognitive control over food and hence increases vulnerability to environmental triggers for binge eating. Thus, the goals of this manuscript were to explore the impact of acute stress on the neural processing of food cues in BN. In Study 1, 10 women with Diagnostic and Statistical Manual of Mental Disorders (5th ed.; DSM-5; American Psychiatric Association, 2013) BN and 10 healthy controls participated in an fMRI paradigm examining the neural correlates of visual food cue processing pre and post an acute stress induction. Whole brain analysis indicated that women with BN exhibited significant decreases in activation in the precuneus, associated with self-referential processing, the paracingulate gyrus, and the anterior vermis of the cerebellum. Healthy controls exhibited increased activation in these regions in response to food cues poststress. In Study 2, 17 women with DSM-5 BN or otherwise specified feeding and eating disorder with BN symptoms participated in the same paradigm. A region of interest analysis replicated findings from Study 1. Replication of imaging findings in 2 different samples suggests the potential importance of these regions in relation to BN. Decreased activation in the precuneus, specifically, is consistent with models of BN that posit that binge eating serves as a concrete distraction from aversive internal stimuli. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  12. The Effects of Social Context and Acute Stress on Decision Making Under Uncertainty.

    PubMed

    FeldmanHall, Oriel; Raio, Candace M; Kubota, Jennifer T; Seiler, Morgan G; Phelps, Elizabeth A

    2015-12-01

    Uncertainty preferences are typically studied in neutral, nonsocial contexts. This approach, however, fails to capture the dynamic factors that influence choices under uncertainty in the real world. Our goal was twofold: to test whether uncertainty valuation is similar across social and nonsocial contexts, and to investigate the effects of acute stress on uncertainty preferences. Subjects completed matched gambling and trust games following either a control or a stress manipulation. Those who were not under stress exhibited no differences between the amount of money gambled and the amount of money entrusted to partners. In comparison, stressed subjects gambled more money but entrusted less money to partners. We further found that irrespective of stress, subjects were highly attuned to irrelevant feedback in the nonsocial, gambling context, believing that every loss led to a greater chance of winning (the gamblers' fallacy). However, when deciding to trust a stranger, control subjects behaved rationally, treating each new interaction as independent. Stress compromised this adaptive behavior, increasing sensitivity to irrelevant social feedback. © The Author(s) 2015.

  13. Time-Temperature Superposition to Determine the Stress-Rupture of Aramid Fibres

    NASA Astrophysics Data System (ADS)

    Alwis, K. G. N. C.; Burgoyne, C. J.

    2006-07-01

    Conventional creep testing takes a long time to obtain stress-rupture data for aramid fibres at the low stress levels likely to be used in practical applications. However, the rate of creep of aramid can be accelerated by a thermally activated process to obtain the failure of fibres within a few hours. It is possible to obtain creep curves at different temperature levels which can be shifted along the time axis to generate a single curve know as a master curve, from which stress-rupture data can be obtained. This technique is known as the time-temperature superposition principle and will be applied to Kevlar 49 yarns. Important questions relating to the techniques needed to obtain smooth master curves will be discussed, as will the validity the resulting curves and the corresponding stress-rupture lifetime.

  14. Heat Priming Induces Trans-generational Tolerance to High Temperature Stress in Wheat

    PubMed Central

    Wang, Xiao; Xin, Caiyun; Cai, Jian; Zhou, Qin; Dai, Tingbo; Cao, Weixing; Jiang, Dong

    2016-01-01

    Wheat plants are very sensitive to high temperature stress during grain filling. Effects of heat priming applied to the first generation on tolerance of the successive generation to post-anthesis high temperature stress were investigated. Compared with the progeny of non-heat primed plants (NH), the progeny of heat-primed plants (PH) possessed higher grain yield, leaf photosynthesis and activities of antioxidant enzymes and lower cell membrane damage under high temperature stress. In the transcriptome profile, 1430 probes showed obvious difference in expression between PH and NH. These genes were related to signal transduction, transcription, energy, defense, and protein destination and storage, respectively. The gene encoding the lysine-specific histone demethylase 1 (LSD1) which was involved in histone demethylation related to epigenetic modification was up-regulated in the PH compared with NH. The proteome analysis indicated that the proteins involved in photosynthesis, energy production and protein destination and storage were up-regulated in the PH compared with NH. In short, thermos-tolerance was induced through heritable epigenetic alternation and signaling transduction, both processes further triggered prompt modifications of defense related responses in anti-oxidation, transcription, energy production, and protein destination and storage in the progeny of the primed plants under high temperature stress. It was concluded that trans-generation thermo-tolerance was induced by heat priming in the first generation, and this might be an effective measure to cope with severe high-temperature stresses during key growth stages in wheat production. PMID:27148324

  15. Effects of acute tryptophan depletion on affective processing in first-degree relatives of depressive patients and controls after exposure to uncontrollable stress.

    PubMed

    Firk, Christine; Markus, C Rob

    2008-08-01

    Individuals with a family history of depression may be more likely to develop depression due to an innate vulnerability of their serotonergic system. However, even though serotonergic vulnerability may constitute a risk factor in the development of depression, it does not seem to be sufficient to cause a depressive episode. Based on previous data, it is suggested that stress may be a mediating factor. This study examined the role of serotonin (5-HT) in stress coping in individuals with or without a family history of depression. Nineteen healthy first-degree relatives of depressive patients (FH+) and 19 healthy controls without a family history of depression (FH-) were tested in a double-blind placebo-controlled design for affective processing under acute stress exposure, following acute tryptophan depletion (ATD) or placebo. Significant negative effects were found of stress on affective processing in FH- and FH+. In addition, FH- responded slower to positive words after stress only following ATD, whereas FH+ responded marginally slower under stress already after placebo and before stress following ATD. Acute stress exposure reduces positive affective bias; supporting the role of stress as an important predecessor in the development of depression. Furthermore, FH+ may be more susceptible than FH- to the negative effects of stress as well as to the negative effects of ATD. The results support the assumption that the 5-HT system is involved in stress resilience and may be more vulnerable in first-degree relatives of depression.

  16. Bias Stress and Temperature Impact on InGaZnO TFTs and Circuits

    PubMed Central

    Martins, Jorge; Bahubalindruni, Pydi; Rovisco, Ana; Kiazadeh, Asal; Martins, Rodrigo; Fortunato, Elvira; Barquinha, Pedro

    2017-01-01

    This paper focuses on the analysis of InGaZnO thin-film transistors (TFTs) and circuits under the influence of different temperatures and bias stress, shedding light into their robustness when used in real-world applications. For temperature-dependent measurements, a temperature range of 15 to 85 °C was considered. In case of bias stress, both gate and drain bias were applied for 60 min. Though isolated transistors show a variation of drain current as high as 56% and 172% during bias voltage and temperature stress, the employed circuits were able to counteract it. Inverters and two-TFT current mirrors following simple circuit topologies showed a gain variation below 8%, while the improved robustness of a cascode current mirror design is proven by showing a gain variation less than 5%. The demonstration that the proper selection of TFT materials and circuit topologies results in robust operation of oxide electronics under different stress conditions and over a reasonable range of temperatures proves that the technology is suitable for applications such as smart food packaging and wearables. PMID:28773037

  17. Bias Stress and Temperature Impact on InGaZnO TFTs and Circuits.

    PubMed

    Martins, Jorge; Bahubalindruni, Pydi; Rovisco, Ana; Kiazadeh, Asal; Martins, Rodrigo; Fortunato, Elvira; Barquinha, Pedro

    2017-06-21

    This paper focuses on the analysis of InGaZnO thin-film transistors (TFTs) and circuits under the influence of different temperatures and bias stress, shedding light into their robustness when used in real-world applications. For temperature-dependent measurements, a temperature range of 15 to 85 °C was considered. In case of bias stress, both gate and drain bias were applied for 60 min. Though isolated transistors show a variation of drain current as high as 56% and 172% during bias voltage and temperature stress, the employed circuits were able to counteract it. Inverters and two-TFT current mirrors following simple circuit topologies showed a gain variation below 8%, while the improved robustness of a cascode current mirror design is proven by showing a gain variation less than 5%. The demonstration that the proper selection of TFT materials and circuit topologies results in robust operation of oxide electronics under different stress conditions and over a reasonable range of temperatures proves that the technology is suitable for applications such as smart food packaging and wearables.

  18. Effect of temperature stress on circulating biogenic amines in bovine.

    PubMed

    Davis, T P; Johnson, H D; Gehrke, C W

    1984-01-01

    A sensitive, simple and selective chromatographic method using high performance liquid chromatography was developed to measure circulating levels of histamine (HI), norepinephrine (NE), dopamine (DA) and serotonin (5-HT) as indicators of response to thermal stress in two breeds of cattle. Duplicate exposures for 8 hr to 13 degrees C resulted in significantly elevated plasma NE and DA in longhorns but not in Herefords and suggest a relatively greater sensitivity to the cold (13 degrees C) in the longhorn. Environmental temperatures of 32 and 42 degrees C significantly increased rectal temperatures of both breeds with much higher rectal temperatures in Herefords. The 32 and 42 degrees C effects on circulating NE and DA of Herefords were highly significant but not in the longhorn. However, heat stress significantly elevated HI and 5-HT in the longhorn which may account for their relatively greater heat tolerance based on their lower rectal temperatures.

  19. A Randomized Crossover Trial on Acute Stress-Related Physiological Responses to Mountain Hiking

    PubMed Central

    Grafetstätter, Carina; Hartl, Arnulf; Kopp, Martin

    2017-01-01

    Green exercise, defined as physical activity in natural environments, might have positive effects on stress-related physiological measures. Little is known about the acute effects of green exercise bouts lasting longer than 60 min. Therefore, the aim of the present study was to analyze the acute effects of a three-hour green exercise intervention (mountain hiking) on stress-related physiological responses. Using a randomized crossover design, 42 healthy participants were exposed to three different conditions in a field-based experiment: outdoor mountain hiking, indoor treadmill walking, and sedentary control condition (three hours each). At baseline and at follow-up (five minutes after the condition), stress-related physiological responses (salivary cortisol, blood pressure, and heart rate variability) were measured. Salivary cortisol decreased in all conditions, but showed a larger decrease after both mountain hiking and treadmill walking compared to the sedentary control situation (partial η2 = 0.10). No differences were found between mountain hiking and treadmill walking in salivary cortisol. In heart rate variability and blood pressure, changes from baseline to follow-up did not significantly differ between the three conditions. The results indicate that three hours of hiking indoors or outdoors elicits positive effects on salivary cortisol concentration. Environmental effects seem to play a minor role in salivary cortisol, blood pressure, and heart rate variability. PMID:28800067

  20. Critical shear stress for erosion of cohesive soils subjected to temperatures typical of wildfires

    USGS Publications Warehouse

    Moody, J.A.; Dungan, Smith J.; Ragan, B.W.

    2005-01-01

    [1] Increased erosion is a well-known response after wildfire. To predict and to model erosion on a landscape scale requires knowledge of the critical shear stress for the initiation of motion of soil particles. As this soil property is temperature-dependent, a quantitative relation between critical shear stress and the temperatures to which the soils have been subjected during a wildfire is required. In this study the critical shear stress was measured in a recirculating flume using samples of forest soil exposed to different temperatures (40??-550??C) for 1 hour. Results were obtained for four replicates of soils derived from three different types of parent material (granitic bedrock, sandstone, and volcanic tuffs). In general, the relation between critical shear stress and temperature can be separated into three different temperature ranges (275??C), which are similar to those for water repellency and temperature. The critical shear stress was most variable (1.0-2.0 N m-2) for temperatures 2.0 N m-2) between 175?? and 275??C, and was essentially constant (0.5-0.8 N m-2) for temperatures >275??C. The changes in critical shear stress with temperature were found to be essentially independent of soil type and suggest that erosion processes in burned watersheds can be modeled more simply than erosion processes in unburned watersheds. Wildfire reduces the spatial variability of soil erodibility associated with unburned watersheds by eliminating the complex effects of vegetation in protecting soils and by reducing the range of cohesion associated with different types of unburned soils. Our results indicate that modeling the erosional response after a wildfire depends primarily on determining the spatial distribution of the maximum soil temperatures that were reached during the wildfire. Copyright 2005 by the American Geophysical Union.

  1. Temperature and blood flow distribution in the human leg during passive heat stress.

    PubMed

    Chiesa, Scott T; Trangmar, Steven J; González-Alonso, José

    2016-05-01

    The influence of temperature on the hemodynamic adjustments to direct passive heat stress within the leg's major arterial and venous vessels and compartments remains unclear. Fifteen healthy young males were tested during exposure to either passive whole body heat stress to levels approaching thermal tolerance [core temperature (Tc) + 2°C; study 1; n = 8] or single leg heat stress (Tc + 0°C; study 2; n = 7). Whole body heat stress increased perfusion and decreased oscillatory shear index in relation to the rise in leg temperature (Tleg) in all three major arteries supplying the leg, plateauing in the common and superficial femoral arteries before reaching severe heat stress levels. Isolated leg heat stress increased arterial blood flows and shear patterns to a level similar to that obtained during moderate core hyperthermia (Tc + 1°C). Despite modest increases in great saphenous venous (GSV) blood flow (0.2 l/min), the deep venous system accounted for the majority of returning flow (common femoral vein 0.7 l/min) during intense to severe levels of heat stress. Rapid cooling of a single leg during severe whole body heat stress resulted in an equivalent blood flow reduction in the major artery supplying the thigh deep tissues only, suggesting central temperature-sensitive mechanisms contribute to skin blood flow alone. These findings further our knowledge of leg hemodynamic responses during direct heat stress and provide evidence of potentially beneficial vascular alterations during isolated limb heat stress that are equivalent to those experienced during exposure to moderate levels of whole body hyperthermia. Copyright © 2016 the American Physiological Society.

  2. Separating heat stress from moisture stress: analyzing yield response to high temperature in irrigated maize

    NASA Astrophysics Data System (ADS)

    Carter, Elizabeth K.; Melkonian, Jeff; Riha, Susan J.; Shaw, Stephen B.

    2016-09-01

    Several recent studies have indicated that high air temperatures are limiting maize (Zea mays L.) yields in the US Corn Belt and project significant yield losses with expected increases in growing season temperatures. Further work has suggested that high air temperatures are indicative of high evaporative demand, and that decreases in maize yields which correlate to high temperatures and vapor pressure deficits (VPD) likely reflect underlying soil moisture limitations. It remains unclear whether direct high temperature impacts on yields, independent of moisture stress, can be observed under current temperature regimes. Given that projected high temperature and moisture may not co-vary the same way as they have historically, quantitative analyzes of direct temperature impacts are critical for accurate yield projections and targeted mitigation strategies under shifting temperature regimes. To evaluate yield response to above optimum temperatures independent of soil moisture stress, we analyzed climate impacts on irrigated maize yields obtained from the National Corn Growers Association (NCGA) corn yield contests for Nebraska, Kansas and Missouri. In irrigated maize, we found no evidence of a direct negative impact on yield by daytime air temperature, calculated canopy temperature, or VPD when analyzed seasonally. Solar radiation was the primary yield-limiting climate variable. Our analyses suggested that elevated night temperature impacted yield by increasing rates of phenological development. High temperatures during grain-fill significantly interacted with yields, but this effect was often beneficial and included evidence of acquired thermo-tolerance. Furthermore, genetics and management—information uniquely available in the NCGA contest data—explained more yield variability than climate, and significantly modified crop response to climate. Thermo-acclimation, improved genetics and changes to management practices have the potential to partially or completely

  3. Stress Free Temperature Testing and Calculations on Out-of-Autoclave Composites

    NASA Technical Reports Server (NTRS)

    Cox, Sarah B.; Tate, LeNetra C.; Danley, Susan E.; Sampson, Jeffrey W.; Taylor, Brian J.; Sutter, James K.; Miller, Sandi G.

    2013-01-01

    Future launch vehicles will require the incorporation of large composite parts that will make up primary and secondary components of the vehicle. NASA has explored the feasibility of manufacturing these large components using Out-of-Autoclave impregnated carbon fiber composite systems through many composites development projects. Most recently, the Composites for Exploration Project has been looking at the development of a 10 meter diameter fairing structure, similar in size to what will be required for a heavy launch vehicle. The development of new material systems requires the investigation of the material properties and the stress in the parts. Residual stress is an important factor to incorporate when modeling the stresses that a part is undergoing. Testing was performed to verify the stress free temperature with two-ply asymmetric panels. A comparison was done between three newly developed out of autoclave IM7/Bismaleimide (BMI) systems. This paper presents the testing results and the analysis performed to determine the stress free temperature of the materials

  4. The effect of residual stress on performance of high temperature coatings

    NASA Technical Reports Server (NTRS)

    1972-01-01

    Techniques for measurement of residual stress in MoSi2 coatings and the determination of stress in coatings prepared by metalliding, pack and slurry processes are discussed. The stress level can be determined by stress induced deflections or by X-ray techniques. The deflection method is most direct. It is based on the fact that a thin substrate, coated on one side only, is usually curved at room temperature. The radius of curvature is easily measured and readily related to residual stress.

  5. Effect of short-term, high-dose methylprednisolone on oxidative stress in children with acute immune thrombocytopenia.

    PubMed

    Cura, Musa; Koç, Ahmet; Aksoy, Nurten; Özdemir, Zeynep Canan

    2016-12-01

    Immune thrombocytopenia (ITP) is the most common cause of acquired childhood thrombocytopenia and is characterized by increased immune-mediated destruction of circulating thrombocytes. Oxidative damage may be involved in ITP pathogenesis; paraoxonase (PON) and arylesterase (ARE) enzymes are closely associated with the cellular antioxidant system. We investigated the effect of short-term high-dose methylprednisolone (HDMP) treatment on the total oxidant status (TOS), total antioxidant capacity (TAC), oxidative stress index (OSI), and PON and ARE enzymatic activity in children with acute ITP. Thirty children with acute ITP constituted the study group and 30 healthy children constituted the control group. Children with acute ITP were treated with HDMP: 30 mg/kg for 3 days, then 20 mg/kg for 4 days. The TOS, TAC, OSI, PON, and ARE levels were determined before and after 7 days of HDMP treatment. The TAC level ( P <0.001), and PON ( P <0.001) and ARE (P=0.001) activities were lower and the TOS ( P =0.003) and OSI ( P <0.001) levels were higher in children with acute ITP than those in healthy children in the control group. We also observed statistically significant increases in the TAC ( P <0.01), PON ( P <0.001) and ARE levels ( P =0.001) and decreases in the TOS ( P <0.05) and OSI levels ( P <0.05) with 7 days of HDMP treatment compared to their values before treatment. Our study demonstrated increased oxidative stress (OSI and TOC) and decreased antioxidant capacity (TAC), PON, and ARE in ITP patients and that steroid treatment could be effective in reducing the oxidative stress.

  6. Preliminary evidence of attenuated blood pressure reactivity to acute stress in adults following a recent marital separation.

    PubMed

    Grinberg, Austin M; O'Hara, Karey L; Sbarra, David A

    2018-03-01

    This study explores cardiovascular reactivity during an acute-stress task in a sample of recently separated adults. In a cross-sectional design, we examined the association between adults' subjective separation-related distress and changes in heart rate and blood pressure across the acute-stress laboratory paradigm in a sample of 133 (n = 49 men) recently separated adults. Heart rate (HR) and Blood pressure (BP) were recorded across a resting baseline period, a math stressor task, and a recovery period. Multilevel analyses revealed that adults who reported greater separation-related distress exhibited higher initial BP and a slower linear increase in BP across the study period. In addition, adults reporting greater separation-related distress evidenced significantly slower declines in diastolic blood pressure (DBP) following the acute-stress task. HR reactivity was not moderated by separation-related distress. In recently separated adults, preliminary evidence suggests that the context of the stressors may reveal differential patterns of problematic reactivity (exaggerated or blunted responding). Greater emotional intrusion and hyperactivity symptoms may index increased risk for blunted cardiovascular reactivity to general stressors. This pattern of reactivity is consistent with models of allostatic load that emphasise the deleterious effect of hyporesponsivity to environmental demands.

  7. Automated Non-invasive Video-Microscopy of Oyster Spat Heart Rate during Acute Temperature Change: Impact of Acclimation Temperature

    PubMed Central

    Domnik, Nicolle J.; Polymeropoulos, Elias T.; Elliott, Nicholas G.; Frappell, Peter B.; Fisher, John T.

    2016-01-01

    We developed an automated, non-invasive method to detect real-time cardiac contraction in post-larval (1.1–1.7 mm length), juvenile oysters (i.e., oyster spat) via a fiber-optic trans-illumination system. The system is housed within a temperature-controlled chamber and video microscopy imaging of the heart was coupled with video edge-detection to measure cardiac contraction, inter-beat interval, and heart rate (HR). We used the method to address the hypothesis that cool acclimation (10°C vs. 22°C—Ta10 or Ta22, respectively; each n = 8) would preserve cardiac phenotype (assessed via HR variability, HRV analysis and maintained cardiac activity) during acute temperature changes. The temperature ramp (TR) protocol comprised 2°C steps (10 min/experimental temperature, Texp) from 22°C to 10°C to 22°C. HR was related to Texp in both acclimation groups. Spat became asystolic at low temperatures, particularly Ta22 spat (Ta22: 8/8 vs. Ta10: 3/8 asystolic at Texp = 10°C). The rate of HR decrease during cooling was less in Ta10 vs. Ta22 spat when asystole was included in analysis (P = 0.026). Time-domain HRV was inversely related to temperature and elevated in Ta10 vs. Ta22 spat (P < 0.001), whereas a lack of defined peaks in spectral density precluded frequency-domain analysis. Application of the method during an acute cooling challenge revealed that cool temperature acclimation preserved active cardiac contraction in oyster spat and increased time-domain HRV responses, whereas warm acclimation enhanced asystole. These physiologic changes highlight the need for studies of mechanisms, and have translational potential for oyster aquaculture practices. PMID:27445833

  8. High Temperature Uniaxial Compression and Stress-Relaxation Behavior of India-Specific RAFM Steel

    NASA Astrophysics Data System (ADS)

    Shah, Naimish S.; Sunil, Saurav; Sarkar, Apu

    2018-07-01

    India-specific reduced activity ferritic martensitic steel (INRAFM), a modified 9Cr-1Mo grade, has been developed by India as its own structural material for fabrication of the Indian Test Blanket Module (TBM) to be installed in the International Thermonuclear Energy Reactor (ITER). The extensive study on mechanical and physical properties of this material has been currently going on for appraisal of this material before being put to use in the ITER. High temperature compression, stress-relaxation, and strain-rate change behavior of the INRAFM steel have been investigated. The optical microscopic and scanning electron microscopic characterizations were carried out to observe the microstructural changes that occur during uniaxial compressive deformation test. Comparable true plastic stress values at 300 °C and 500 °C and a high drop in true plastic stress at 600 °C were observed during the compression test. Stress-relaxation behaviors were investigated at 500 °C, 550 °C, and 600 °C at a strain rate of 10-3 s-1. The creep properties of the steel at different temperatures were predicted from the stress-relaxation test. The Norton's stress exponent ( n) was found to decrease with the increasing temperature. Using Bird-Mukherjee-Dorn relationship, the temperature-compensated normalized strain rate vs stress was plotted. The stress exponent ( n) value of 10.05 was obtained from the normalized plot. The increasing nature of the strain rate sensitivity ( m) with the test temperature was found from strain-rate change test. The low plastic stability with m 0.06 was observed at 600 °C. The activation volume ( V *) values were obtained in the range of 100 to 300 b3. By comparing the experimental values with the literature, the rate-controlling mechanisms at the thermally activated region of high temperature were found to be the nonconservative movement of jogged screw dislocations and thermal breaking of attractive junctions.

  9. High Temperature Uniaxial Compression and Stress-Relaxation Behavior of India-Specific RAFM Steel

    NASA Astrophysics Data System (ADS)

    Shah, Naimish S.; Sunil, Saurav; Sarkar, Apu

    2018-05-01

    India-specific reduced activity ferritic martensitic steel (INRAFM), a modified 9Cr-1Mo grade, has been developed by India as its own structural material for fabrication of the Indian Test Blanket Module (TBM) to be installed in the International Thermonuclear Energy Reactor (ITER). The extensive study on mechanical and physical properties of this material has been currently going on for appraisal of this material before being put to use in the ITER. High temperature compression, stress-relaxation, and strain-rate change behavior of the INRAFM steel have been investigated. The optical microscopic and scanning electron microscopic characterizations were carried out to observe the microstructural changes that occur during uniaxial compressive deformation test. Comparable true plastic stress values at 300 °C and 500 °C and a high drop in true plastic stress at 600 °C were observed during the compression test. Stress-relaxation behaviors were investigated at 500 °C, 550 °C, and 600 °C at a strain rate of 10-3 s-1. The creep properties of the steel at different temperatures were predicted from the stress-relaxation test. The Norton's stress exponent (n) was found to decrease with the increasing temperature. Using Bird-Mukherjee-Dorn relationship, the temperature-compensated normalized strain rate vs stress was plotted. The stress exponent (n) value of 10.05 was obtained from the normalized plot. The increasing nature of the strain rate sensitivity (m) with the test temperature was found from strain-rate change test. The low plastic stability with m 0.06 was observed at 600 °C. The activation volume (V *) values were obtained in the range of 100 to 300 b3. By comparing the experimental values with the literature, the rate-controlling mechanisms at the thermally activated region of high temperature were found to be the nonconservative movement of jogged screw dislocations and thermal breaking of attractive junctions.

  10. Perception of a hectic hospital environment at admission relates to acute stress disorder symptoms in myocardial infarction patients.

    PubMed

    Meister, Rebecca Elisabeth; Weber, Tania; Princip, Mary; Schnyder, Ulrich; Barth, Jürgen; Znoj, Hansjörg; Schmid, Jean-Paul; von Känel, Roland

    2016-01-01

    Hospital crowding is a public health problem that may impact on the quality of medical treatment and increase the risk of developing traumatic stress, e.g., after myocardial infarction (MI). This study examines whether subjective appraisal of crowding at hospital admission due to MI is associated with acute stress disorder (ASD) symptoms. We investigated 102 consecutive patients with acute MI within 48h after having reached stable circulatory conditions. The appraisal of crowding was measured by the retrospective assessment of the perception of a hectic hospital environment at admission. Furthermore, patients completed the Acute Stress Disorder Scale to rate the psychological stress reaction. The perception of a hectic hospital environment was associated with the development of ASD symptoms (r=0.254, P=.013) independently of demographic, peritraumatic and medical factors. Post hoc analysis revealed associations with dissociative (r=0.211, P=.041), reexperiencing (r=0.184, P=.074) and arousal (r=0.179, P=.083) symptoms. The findings suggest that, besides objective circumstances, the way hospital admission due to MI is perceived by the patient may influence the development of MI-triggered ASD symptoms. The psychological and physiological long-term outcomes of the perception of a hectic hospital environment and the role of preventive interventions need further examination. Copyright © 2016 Elsevier Inc. All rights reserved.

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

    ERIC Educational Resources Information Center

    Chida, Yoichi; Hamer, Mark

    2008-01-01

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

  12. Internal stress-induced melting below melting temperature at high-rate laser heating

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hwang, Yong Seok, E-mail: yshwang@iastate.edu; Levitas, Valery I., E-mail: vlevitas@iastate.edu

    In this Letter, continuum thermodynamic and phase field approaches (PFAs) predicted internal stress-induced reduction in melting temperature for laser-irradiated heating of a nanolayer. Internal stresses appear due to thermal strain under constrained conditions and completely relax during melting, producing an additional thermodynamic driving force for melting. Thermodynamic melting temperature for Al reduces from 933.67 K for a stress-free condition down to 898.1 K for uniaxial strain and to 920.8 K for plane strain. Our PFA simulations demonstrated barrierless surface-induced melt nucleation below these temperatures and propagation of two solid-melt interfaces toward each other at the temperatures very close to the corresponding predicted thermodynamicmore » equilibrium temperatures for the heating rate Q≤1.51×10{sup 10}K/s. At higher heating rates, kinetic superheating competes with a reduction in melting temperature and melting under uniaxial strain occurs at 902.1 K for Q = 1.51 × 10{sup 11 }K/s and 936.9 K for Q = 1.46 × 10{sup 12 }K/s.« less

  13. Acetaminophen (Paracetamol) Induces Hypothermia During Acute Cold Stress.

    PubMed

    Foster, Josh; Mauger, Alexis R; Govus, Andrew; Hewson, David; Taylor, Lee

    2017-11-01

    Acetaminophen is an over-the-counter drug used to treat pain and fever, but it has also been shown to reduce core temperature (T c ) in the absence of fever. However, this side effect is not well examined in humans, and it is unknown if the hypothermic response to acetaminophen is exacerbated with cold exposure. To address this question, we mapped the thermoregulatory responses to acetaminophen and placebo administration during exposure to acute cold (10 °C) and thermal neutrality (25 °C). Nine healthy Caucasian males (aged 20-24 years) participated in the experiment. In a double-blind, randomised, repeated measures design, participants were passively exposed to a thermo-neutral or cold environment for 120 min, with administration of 20 mg/kg lean body mass acetaminophen or a placebo 5 min prior to exposure. T c , skin temperature (T sk ), heart rate, and thermal sensation were measured every 10 min, and mean arterial pressure was recorded every 30 min. Data were analysed using linear mixed effects models. Differences in thermal sensation were analysed using a cumulative link mixed model. Acetaminophen had no effect on T c in a thermo-neutral environment, but significantly reduced T c during cold exposure, compared with a placebo. T c was lower in the acetaminophen compared with the placebo condition at each 10-min interval from 80 to 120 min into the trial (all p < 0.05). On average, T c decreased by 0.42 ± 0.13 °C from baseline after 120 min of cold exposure (range 0.16-0.57 °C), whereas there was no change in the placebo group (0.01 ± 0.1 °C). T sk , heart rate, thermal sensation, and mean arterial pressure were not different between conditions (p > 0.05). This preliminary trial suggests that acetaminophen-induced hypothermia is exacerbated during cold stress. Larger scale trials seem warranted to determine if acetaminophen administration is associated with an increased risk of accidental hypothermia, particularly in vulnerable

  14. Comparison of estimated core body temperature measured with the BioHarness and rectal temperature under several heat stress conditions.

    PubMed

    Seo, Yongsuk; DiLeo, Travis; Powell, Jeffrey B; Kim, Jung-Hyun; Roberge, Raymond J; Coca, Aitor

    2016-08-01

    Monitoring and measuring core body temperature is important to prevent or minimize physiological strain and cognitive dysfunction for workers such as first responders (e.g., firefighters) and military personnel. The purpose of this study is to compare estimated core body temperature (Tco-est), determined by heart rate (HR) data from a wearable chest strap physiology monitor, to standard rectal thermometry (Tre) under different conditions.  Tco-est and Tre measurements were obtained in thermoneutral and heat stress conditions (high temperature and relative humidity) during four different experiments including treadmill exercise, cycling exercise, passive heat stress, and treadmill exercise while wearing personal protective equipment (PPE).  Overall, the mean Tco-est did not differ significantly from Tre across the four conditions. During exercise at low-moderate work rates under heat stress conditions, Tco-est was consistently higher than Tre at all-time points. Tco-est underestimated temperature compared to Tre at rest in heat stress conditions and at a low work rate under heat stress while wearing PPE. The mean differences between the two measurements ranged from -0.1 ± 0.4 to 0.3 ± 0.4°C and Tco-est correlated well with HR (r = 0.795 - 0.849) and mean body temperature (r = 0.637 - 0.861).  These results indicate that, the comparison of Tco-est to Tre may result in over- or underestimation which could possibly lead to heat-related illness during monitoring in certain conditions. Modifications to the current algorithm should be considered to address such issues.

  15. Mood and cortisol responses following tryptophan-rich hydrolyzed protein and acute stress in healthy subjects with high and low cognitive reactivity to depression.

    PubMed

    Firk, Christine; Markus, C Rob

    2009-06-01

    It is suggested that stress particularly in subjects with high cognitive reactivity (CR), a psychological vulnerability marker of depression, may increase or even induce serotonergic vulnerability, which in turn may lead to reduced serotonin (5-HT) function, decreased stress coping and an increased risk to develop depressive symptoms. The aim of the present study was to investigate the beneficial effects of 5-HT augmentation through a tryptophan-rich hydrolyzed protein (HP) on mood and stress coping in subjects with high and low CR. We hypothesized that subjects with high CR are more responsive to the beneficial effects of HP than subjects with low CR particularly after acute stress exposure. In a double-blind, crossover study, participants' mood and cortisol was assessed before and after acute stress exposure either following intake of HP or a standard casein protein (CP) as control condition. HP significantly increased positive mood in all subjects and dampened the cortisol response to acute stress. No differences were found between high and low CR subjects. To conclude, because dietary treatment with HP has beneficial effects on mood and physiological stress coping in both high and low CR subjects, HP may be a good dietary method for augmenting brain TRP and 5-HT and thus 5-HT linked stress resilience.

  16. Growth and Development Temperature Influences Level of Tolerance to High Light Stress 1

    PubMed Central

    Steffen, Kenneth L.; Palta, Jiwan P.

    1989-01-01

    The influence of growth and development temperature on the relative tolerance of photosynthetic tissue to high light stress at chilling temperatures was investigated. Two tuber-bearing potato species, Solanum tuberosum L. cv Red Pontiac and Solanum commersonii were grown for 4 weeks, at either 12 or 24°C with 12 hours of about 375 micromoles per second per square meter of photosynthetically active radiation. Paired leaf discs were cut from directly across the midvein of leaflets of comparable developmental stage and light environment from each species at each growth temperature treatment. One disc of each pair was exposed to 1°C and about 1000 micromoles per second per square meter photosynthetically active radiation for 4 hours, and the other disc was held at 1°C in total darkness for the same duration. Photosynthetic tissue of S. tuberosum, developed at 12°C, was much more tolerant to high light and low temperature stress than tissue developed under 24°C conditions. Following the high light treatment, 24°C-grown S. tuberosum tissue demonstrated light-limited and light-saturated rates that were approximately 50% of their paired dark controls. In contrast, the 12°C-grown tissue from S. tuberosum that was subjected to the light stress showed only a 18 and 6% reduction in light-limited and light-saturated rates of photosynthetic oxygen evolution, respectively. Tissue from 24°C-grown S. commersonii was much less sensitive to the light stress than was tissue from S. tuberosum grown under the same conditions. The results presented here demonstrate that: (a) acclimation of S. tuberosum to lower temperature growth conditions with a constant light environment, results in the increased capacity of photosynthetic tissue to tolerate high light stress at chilling temperature and (b) following growth and development at relatively high temperatures S. commersonii, a frost- and heat-tolerant wild species, has a much greater tolerance to the high light stress at chilling

  17. An enriched environment reduces the stress level and locomotor activity induced by acute morphine treatment and by saline after chronic morphine treatment in mice.

    PubMed

    Xu, Jia; Sun, Jinling; Xue, Zhaoxia; Li, Xinwang

    2014-06-18

    This study investigated the relationships among an enriched environment, stress levels, and drug addiction. Mice were divided randomly into four treatment groups (n=12 each): enriched environment without restraint stress (EN), standard environment without restraint stress (SN), enriched environment with restraint stress (ES), and standard environment with restraint stress (SS). Mice were reared in the respective environment for 45 days. Then, the ES and SS groups were subjected to restraint stress daily (2 h/day) for 14 days, whereas the EN and SN groups were not subjected to restraint stress during this stage. The stress levels of all mice were tested in the elevated plus maze immediately after exposure to restraint stress. After the 2-week stress testing period, mice were administered acute or chronic morphine (5 mg/kg) treatment for 7 days. Then, after a 7-day withdrawal period, the mice were injected with saline (1 ml/kg) or morphine (5 mg/kg) daily for 2 days to observe locomotor activity. The results indicated that the enriched environment reduced the stress and locomotor activity induced by acute morphine administration or saline after chronic morphine treatment. However, the enriched environment did not significantly inhibit locomotor activity induced by morphine challenge. In addition, the stress level did not mediate the effect of the enriched environment on drug-induced locomotor activity after acute or chronic morphine treatment.

  18. Effects of Saccharomyces cerevisiae or boulardii yeasts on acute stress induced intestinal dysmotility.

    PubMed

    West, Christine; Stanisz, Andrew M; Wong, Annette; Kunze, Wolfgang A

    2016-12-28

    To investigate the capacity of Saccharomyces cerevisiae ( S. cerevisiae ) and Saccharomyces boulardii ( S. boulardii ) yeasts to reverse or to treat acute stress-related intestinal dysmotility. Adult Swiss Webster mice were stressed for 1 h in a wire-mesh restraint to induce symptoms of intestinal dysmotility and were subsequently killed by cervical dislocation. Jejunal and colon tissue were excised and placed within a tissue perfusion bath in which S. cerevisiae , S. boulardii , or their supernatants were administered into the lumen. Video recordings of contractility and gut diameter changes were converted to spatiotemporal maps and the velocity, frequency, and amplitude of propagating contractile clusters (PCC) were measured. Motility pre- and post-treatment was compared between stressed animals and unstressed controls. S. boulardii and S. cerevisiae helped to mediate the effects of stress on the small and large intestine. Restraint stress reduced jejunal transit velocity (mm/s) from 2.635 ± 0.316 to 1.644 ± 0.238, P < 0.001 and jejunal transit frequency (Hz) from 0.032 ± 0.008 to 0.016 ± 0.005, P < 0.001. Restraint stress increased colonic transit velocity (mm/s) from 0.864 ± 0.183 to 1.432 ± 0.329, P < 0.001 and frequency to a lesser degree. Luminal application of S. boulardii helped to restore jejunal and colonic velocity towards the unstressed controls; 1.833 ± 0.688 to 2.627 ± 0.664, P < 0.001 and 1.516 ± 0.263 to 1.036 ± 0.21, P < 0.001, respectively. S. cerevisiae also had therapeutic effects on the stressed gut, but was most apparent in the jejunum. S. cerevisiae increased PCC velocity in the stressed jejunum from 1.763 ± 0.397 to 2.017 ± 0.48, P = 0.0031 and PCC frequency from 0.016 ± 0.009 to 0.027 ± 0.007, P < 0.001. S. cerevisiae decreased colon PCC velocity from 1.647 ± 0.187 to 1.038 ± 0.222, P < 0.001. Addition of S. boulardii or S. cerevisiae supernatants also helped to restore motility to unstressed values in similar capacity

  19. Effects of Saccharomyces cerevisiae or boulardii yeasts on acute stress induced intestinal dysmotility

    PubMed Central

    West, Christine; Stanisz, Andrew M; Wong, Annette; Kunze, Wolfgang A

    2016-01-01

    AIM To investigate the capacity of Saccharomyces cerevisiae (S. cerevisiae) and Saccharomyces boulardii (S. boulardii) yeasts to reverse or to treat acute stress-related intestinal dysmotility. METHODS Adult Swiss Webster mice were stressed for 1 h in a wire-mesh restraint to induce symptoms of intestinal dysmotility and were subsequently killed by cervical dislocation. Jejunal and colon tissue were excised and placed within a tissue perfusion bath in which S. cerevisiae, S. boulardii, or their supernatants were administered into the lumen. Video recordings of contractility and gut diameter changes were converted to spatiotemporal maps and the velocity, frequency, and amplitude of propagating contractile clusters (PCC) were measured. Motility pre- and post-treatment was compared between stressed animals and unstressed controls. RESULTS S. boulardii and S. cerevisiae helped to mediate the effects of stress on the small and large intestine. Restraint stress reduced jejunal transit velocity (mm/s) from 2.635 ± 0.316 to 1.644 ± 0.238, P < 0.001 and jejunal transit frequency (Hz) from 0.032 ± 0.008 to 0.016 ± 0.005, P < 0.001. Restraint stress increased colonic transit velocity (mm/s) from 0.864 ± 0.183 to 1.432 ± 0.329, P < 0.001 and frequency to a lesser degree. Luminal application of S. boulardii helped to restore jejunal and colonic velocity towards the unstressed controls; 1.833 ± 0.688 to 2.627 ± 0.664, P < 0.001 and 1.516 ± 0.263 to 1.036 ± 0.21, P < 0.001, respectively. S. cerevisiae also had therapeutic effects on the stressed gut, but was most apparent in the jejunum. S. cerevisiae increased PCC velocity in the stressed jejunum from 1.763 ± 0.397 to 2.017 ± 0.48, P = 0.0031 and PCC frequency from 0.016 ± 0.009 to 0.027 ± 0.007, P < 0.001. S. cerevisiae decreased colon PCC velocity from 1.647 ± 0.187 to 1.038 ± 0.222, P < 0.001. Addition of S. boulardii or S. cerevisiae supernatants also helped to restore motility to unstressed values in similar

  20. Effect of Acute Mental Stress on Heart Rate and QT Variability in Postmyocardial Infarction Patients.

    PubMed

    Magrì, Damiano; Piccirillo, Gianfranco; Quaglione, Raffaele; Dell'armi, Annalaura; Mitra, Marilena; Velitti, Stefania; Di Barba, Daniele; Lizio, Andrea; Maisto, Damiana; Barillà, Francesco

    2012-01-01

    Emotionally charged events are associated with an increased risk of sudden cardiac death (SCD). In this study we assessed RR and QT variability index (QTVI) at baseline during anger recall test (AR). We calculated QTVI from a 5-min ECG recording and from a 10-beats segment around the presumed maximum sympathetic activation in thirty post-myocardial infarction patients under β-blocker therapy and 10 controls underwent. In all groups, the low-frequency component of RR and SBP increased during AR. In all recordings, the QTVI calculated on a 5-min ECG recording and the QTVI(10 beats) were higher in patients than in controls (P < 0.05). The QTVI during AR remained unchanged from baseline within each group. Conversely, during AR, the QTVI(10 beats) in controls diminished significantly (P < 0.05) from baseline whereas in patients remained unchanged. The inability to buffer an acute stress-induced increase in sympathetic activity could explain why events charged with acute stress are associated with an increased risk of ventricular arrhythmias in this setting of patients and support the role of cognitive behavior stress management strategies.

  1. Effect of Acute Mental Stress on Heart Rate and QT Variability in Postmyocardial Infarction Patients

    PubMed Central

    Magrì, Damiano; Piccirillo, Gianfranco; Quaglione, Raffaele; Dell'Armi, Annalaura; Mitra, Marilena; Velitti, Stefania; Di Barba, Daniele; Lizio, Andrea; Maisto, Damiana; Barillà, Francesco

    2012-01-01

    Emotionally charged events are associated with an increased risk of sudden cardiac death (SCD). In this study we assessed RR and QT variability index (QTVI) at baseline during anger recall test (AR). We calculated QTVI from a 5-min ECG recording and from a 10-beats segment around the presumed maximum sympathetic activation in thirty post-myocardial infarction patients under β-blocker therapy and 10 controls underwent. In all groups, the low-frequency component of RR and SBP increased during AR. In all recordings, the QTVI calculated on a 5-min ECG recording and the QTVI10 beats were higher in patients than in controls (P < 0.05). The QTVI during AR remained unchanged from baseline within each group. Conversely, during AR, the QTVI10 beats in controls diminished significantly (P < 0.05) from baseline whereas in patients remained unchanged. The inability to buffer an acute stress-induced increase in sympathetic activity could explain why events charged with acute stress are associated with an increased risk of ventricular arrhythmias in this setting of patients and support the role of cognitive behavior stress management strategies. PMID:22844616

  2. Acute toxicity of crude oil water accommodated fraction on marine copepods: the relative importance of acclimatization temperature and body size.

    PubMed

    Jiang, Zhibing; Huang, Yijun; Chen, Quanzhen; Zeng, Jiangning; Xu, Xiaoqun

    2012-10-01

    Recent oil spillage accidents around the world greatly increase harmful risks to marine ecology. This study evaluated the influences of petroleum water accommodated fraction (WAF) on 15 typical species of marine copepods collected from a subtropical bay in East China Sea at different seasons. Copepods showed impaired swimming ability, restlessness, loss of balance, anoxic coma, and even death when they were acutely exposed to the crude oil WAF under laboratory conditions. The LC(50) values (expressed in total petroleum hydrocarbon concentration) indicated that the tolerances of copepods to WAF decreased significantly (P < 0.05) with increased exposure duration and natural water temperatures (acclimatization temperature). The sensitivity of the copepods was species-specific (P < 0.01), and there was a significant (P < 0.05) positive correlation between the 48-h LC(50) and body size. Therefore, the small copepod species confront more survival challenges under oil contamination stress, especially in the warm months or regions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Attenuated Stress Response to Acute Restraint and Forced Swimming Stress in Arginine Vasopressin 1b Receptor Subtype (Avpr1b) Receptor Knockout Mice and Wild-Type Mice Treated with a Novel Avpr1b Receptor Antagonist

    PubMed Central

    Roper, J A; Craighead, M; O’Carroll, A-M; Lolait, S J

    2010-01-01

    Arginine vasopressin (AVP) synthesised in the parvocellular region of the hypothalamic paraventricular nucleus and released into the pituitary portal vessels acts on the 1b receptor subtype (Avpr1b) present in anterior pituitary corticotrophs to modulate the release of adrenocorticotrophic hormone (ACTH). Corticotrophin-releasing hormone is considered the major drive behind ACTH release; however, its action is augmented synergistically by AVP. To determine the extent of vasopressinergic influence in the hypothalamic-pituitary-adrenal axis response to restraint and forced swimming stress, we compared the stress hormone levels [plasma ACTH in both stressors and corticosterone (CORT) in restraint stress only] following acute stress in mutant Avpr1b knockout (KO) mice compared to their wild-type controls following the administration of a novel Avpr1b antagonist. Restraint and forced swimming stress-induced increases in plasma ACTH were significantly diminished in mice lacking a functional Avpr1b and in wild-type mice that had been pre-treated with Avpr1b antagonist. A corresponding decrease in plasma CORT levels was also observed in acute restraint-stressed knockout male mice, and in Avpr1b-antagonist-treated male wild-type mice. By contrast, plasma CORT levels were not reduced in acutely restraint-stressed female knockout animals, or in female wild-type animals pre-treated with Avpr1b antagonist. These results demonstrate that pharmacological antagonism or inactivation of Avpr1b causes a reduction in the hypothalamic-pituitary-adrenal (HPA) axis response, particularly ACTH, to acute restraint and forced swimming stress, and show that Avpr1b knockout mice constitute a model by which to study the contribution of Avpr1b to the HPA axis response to acute stressors. PMID:20846299

  4. Attenuated stress response to acute restraint and forced swimming stress in arginine vasopressin 1b receptor subtype (Avpr1b) receptor knockout mice and wild-type mice treated with a novel Avpr1b receptor antagonist.

    PubMed

    Roper, J A; Craighead, M; O'Carroll, A-M; Lolait, S J

    2010-11-01

    Arginine vasopressin (AVP) synthesised in the parvocellular region of the hypothalamic paraventricular nucleus and released into the pituitary portal vessels acts on the 1b receptor subtype (Avpr1b) present in anterior pituitary corticotrophs to modulate the release of adrenocorticotrophic hormone (ACTH). Corticotrophin-releasing hormone is considered the major drive behind ACTH release; however, its action is augmented synergistically by AVP. To determine the extent of vasopressinergic influence in the hypothalamic-pituitary-adrenal axis response to restraint and forced swimming stress, we compared the stress hormone levels [plasma ACTH in both stressors and corticosterone (CORT) in restraint stress only] following acute stress in mutant Avpr1b knockout (KO) mice compared to their wild-type controls following the administration of a novel Avpr1b antagonist. Restraint and forced swimming stress-induced increases in plasma ACTH were significantly diminished in mice lacking a functional Avpr1b and in wild-type mice that had been pre-treated with Avpr1b antagonist. A corresponding decrease in plasma CORT levels was also observed in acute restraint-stressed knockout male mice, and in Avpr1b-antagonist-treated male wild-type mice. By contrast, plasma CORT levels were not reduced in acutely restraint-stressed female knockout animals, or in female wild-type animals pre-treated with Avpr1b antagonist. These results demonstrate that pharmacological antagonism or inactivation of Avpr1b causes a reduction in the hypothalamic-pituitary-adrenal (HPA) axis response, particularly ACTH, to acute restraint and forced swimming stress, and show that Avpr1b knockout mice constitute a model by which to study the contribution of Avpr1b to the HPA axis response to acute stressors. © 2010 The Authors. Journal of Neuroendocrinology © 2010 Blackwell Publishing Ltd.

  5. Oxidative stress in rat kidneys due to 3,4-methylenedioxymetamphetamine (ecstasy) toxicity.

    PubMed

    Ninković, Milica; Selaković, Vesna; Dukić, Mirjana; Milosavljević, Petar; Vasiljević, Ivana; Jovanović, Marina; Malicević, Zivorad

    2008-02-01

    The mechanism of MDMA (3,4-methylenedioxymethamphetamine)-induced toxicity is believed to be, in part, due to enhanced oxidative stress. As MDMA is eliminated via the kidney, the aim of this study was to investigate whether MDMA created conditions of oxidative stress within rat kidney. Adult male Wistar rats were divided into three groups, control treatment (water), acute MDMA administration (single oral dose: 5, 10, 20 or 40 mg/kg body weight) and subacute MDMA administration (5, 10, or 20 mg/kg body weight per day during 14 days). Animals were sacrificed 8 h after the single oral MDMA administration in the acute MDMA administration group and after the last MDMA administration in the subacute MDMA administration group. Rectal temperature measurements, oxidative stress status parameters and histological examinations were performed. In all MDMA-administered rats, rectal temperature markedly increased peaking approximately 1 h after MDMA ingestion. Superoxide dismutase activity and thiobarbituric acid reactive substances increased after MDMA administration. Histological examinations of the kidney revealed dose-dependent disruption of tissue structure in subacute MDMA-administered rats. The latter was not observed in acute MDMA-administered rats.

  6. Acute Stress-Induced Epigenetic Modulations and Their Potential Protective Role Toward Depression

    PubMed Central

    Rusconi, Francesco; Battaglioli, Elena

    2018-01-01

    Psychiatric disorders entail maladaptive processes impairing individuals’ ability to appropriately interface with environment. Among them, depression is characterized by diverse debilitating symptoms including hopelessness and anhedonia, dramatically impacting the propensity to live a social and active life and seriously affecting working capability. Relevantly, besides genetic predisposition, foremost risk factors are stress-related, such as experiencing chronic psychosocial stress—including bullying, mobbing and abuse—, and undergoing economic crisis or chronic illnesses. In the last few years the field of epigenetics promised to understand core mechanisms of gene-environment crosstalk, contributing to get into pathogenic processes of many disorders highly influenced by stressful life conditions. However, still very little is known about mechanisms that tune gene expression to adapt to the external milieu. In this Perspective article, we discuss a set of protective, functionally convergent epigenetic processes induced by acute stress in the rodent hippocampus and devoted to the negative modulation of stress-induced immediate early genes (IEGs) transcription, hindering stress-driven morphostructural modifications of corticolimbic circuitry. We also suggest that chronic stress damaging protective epigenetic mechanisms, could bias the functional trajectory of stress-induced neuronal morphostructural modification from adaptive to maladaptive, contributing to the onset of depression in vulnerable individuals. A better understanding of the epigenetic response to stress will be pivotal to new avenues of therapeutic intervention to treat depression, especially in light of limited efficacy of available antidepressant drugs. PMID:29904343

  7. Endoplasmic reticulum stress-regulated CXCR3 pathway mediates inflammation and neuronal injury in acute glaucoma

    PubMed Central

    Ha, Y; Liu, H; Xu, Z; Yokota, H; Narayanan, S P; Lemtalsi, T; Smith, S B; Caldwell, R W; Caldwell, R B; Zhang, W

    2015-01-01

    Acute glaucoma is a leading cause of irreversible blindness in East Asia. The mechanisms underlying retinal neuronal injury induced by a sudden rise in intraocular pressure (IOP) remain obscure. Here we demonstrate that the activation of CXCL10/CXCR3 axis, which mediates the recruitment and activation of inflammatory cells, has a critical role in a mouse model of acute glaucoma. The mRNA and protein expression levels of CXCL10 and CXCR3 were significantly increased after IOP-induced retinal ischemia. Blockade of the CXCR3 pathway by deleting CXCR3 gene significantly attenuated ischemic injury-induced upregulation of inflammatory molecules (interleukin-1β and E-selectin), inhibited the recruitment of microglia/monocyte to the superficial retina, reduced peroxynitrite formation, and prevented the loss of neurons within the ganglion cell layer. In contrast, intravitreal delivery of CXCL10 increased leukocyte recruitment and retinal cell apoptosis. Inhibition of endoplasmic reticulum (ER) stress with chemical chaperones partially blocked ischemic injury-induced CXCL10 upregulation, whereas induction of ER stress with tunicamycin enhanced CXCL10 expression in retina and primary retinal ganglion cells. Interestingly, deleting CXCR3 attenuated ER stress-induced retinal cell death. In conclusion, these results indicate that ER stress-medicated activation of CXCL10/CXCR3 pathway has an important role in retinal inflammation and neuronal injury after high IOP-induced ischemia. PMID:26448323

  8. Stressed (acute) mice display neuroimmunodysregulation and defective innate immune response against coliform infection.

    PubMed

    Mehrzad, Jalil; Shajari, Majid; Saleh-Moghaddam, Massoud; Sarmad-Nabavi, Mohammad

    2015-09-01

    We examined the impact of acute restraint stress (ARS) with(out) intraperitoneal E. coli infection on TLR4 mRNA abundance in brain and spleen, clinical signs, cytokines and oxidative loads and peritoneal E. coli growth in balb/c mice. ARS exacerbated E. coli virulence and behavioral abnormality. At different post-stress hour the pattern and intensity of TLR4 activity differed in brain and spleen. While TLR4 stimulation in spleen of E. coli-infected mice was maximal, it superseded in brain of post-stressed E. coli-infected mice. ARS and E. coli infection elicited systemic pro-inflammatory and pro-oxidant status, with defective peritoneal E. coli clearance in post-ARS mice. Continuous TLR4 activation in post-stressed mice partially disarms innate immune response, and contributes to inappropriate host-E. coli interactions and thus neuroimmune dysregulation/toxicity. The description of these observed novel effects induced by ARS will provide a basis for deeper investigations of the effects from increasingly stress-oriented rural/urban life upon neuroimmune system. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Acute stress worsens the deficits in appetitive behaviors for social and sexual stimuli displayed by rats after long-term withdrawal from morphine.

    PubMed

    Bai, Yunjing; Belin, David; Zheng, Xigeng; Liu, Zhengkui; Zhang, Yue

    2017-06-01

    Negative affective states, e.g., anhedonia, are suggested to be involved in the long-lasting motivational processes associated with relapse. Here, we investigated whether anhedonic behaviors could be elicited by an acute stress after protracted abstinence from morphine. The behavioral responses to natural stimuli following exposure to an acute stress were examined after 14 days of withdrawal from morphine. Male rats were pretreated with either a binge-like morphine regimen or daily saline injections for 5 days. The motivation for two natural stimuli, i.e., a social stimulus (male rat) and a sexual stimulus (estrous female rat), was measured, following exposure to an acute stress (intermittent foot shock, 0.5 mA * 0.5 s * 10 min; mean inter-shock interval 40 s), under three conditions: free approach and effort- and conflict-based approaches. Foot-shock-induced stress did not influence free-approach behavior (sniffing time) towards the social or sexual stimulus. However, in the effort-based approach task, the stressed morphine-withdrawn rats demonstrated an attenuated motivation to climb over a partition to approach the social stimulus while the stressed saline-pretreated rats showed an increased motivation to approach the social stimulus. When an aversive stimulus (pins) was introduced in order to induce an approach-avoidance conflict, both drug-withdrawn and drug-naïve groups exhibited a bimodal distribution of approach behavior towards the sexual stimulus after the stress was introduced, i.e., the majority of rats had low risky appetitive behaviors but a minority of them showed rather highly "risky" approach behavior. The acute stress induces differential motivational deficits for social and sexual rewards in protracted drug-abstinent rats.

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

    PubMed

    Ordaz, Sarah; Luna, Beatriz

    2012-08-01

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

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

    PubMed Central

    Ordaz, Sarah; Luna, Beatriz

    2012-01-01

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

  12. Parent and Child Agreement for Acute Stress Disorder, Post-Traumatic Stress Disorder and Other Psychopathology in a Prospective Study of Children and Adolescents Exposed to Single-Event Trauma

    ERIC Educational Resources Information Center

    Meiser-Stedman, Richard; Smith, Patrick; Glucksman, Edward; Yule, William; Dalgleish, Tim

    2007-01-01

    Examining parent-child agreement for Acute Stress Disorder (ASD) and Post-Traumatic Stress Disorder (PTSD) in children and adolescents is essential for informing the assessment of trauma-exposed children, yet no studies have examined this relationship using appropriate statistical techniques. Parent-child agreement for these disorders was examined…

  13. Acute social stress-induced immunomodulation in pigs high and low responders to ACTH.

    PubMed

    Bacou, Elodie; Haurogné, Karine; Mignot, Grégoire; Allard, Marie; De Beaurepaire, Laurence; Marchand, Jordan; Terenina, Elena; Billon, Yvon; Jacques, Julien; Bach, Jean-Marie; Mormède, Pierre; Hervé, Julie; Lieubeau, Blandine

    2017-02-01

    Pig husbandry is known as an intensive breeding system, piglets being submitted to multiple stressful events such as early weaning, successive mixing, crowding and shipping. These stressors are thought to impair immune defences and might contribute, at least partly, to the prophylactic use of antibiotics. Robustness was recently defined as the ability of an individual to express a high-production potential in a wide variety of environmental conditions. Increasing robustness thus appears as a valuable option to improve resilience to stressors and could be obtained by selecting piglets upon their adrenocortical activity. In this study, we aimed at depicting the consequences of an acute social stress on the immune capacity of piglets genetically selected upon divergent hypothalamic-pituitary-adrenocortical (HPA) axis activity. For this purpose, we monitored neuroendocrine and immune parameters, in high- (HPA hi ) and low- (HPA lo ) responders to ACTH, just before and immediately after a one-hour mixing with unfamiliar conspecifics. As expected, stressed piglets displayed higher levels of circulating cortisol and norepinephrine. Blood cell count analysis combined to flow cytometry revealed a stress-induced leukocyte mobilization in the bloodstream with a specific recruitment of CD8α + lymphocytes. Besides, one-hour mixing decreased LPS-induced IL-8 and TNFα secretions in whole-blood assays (WBA) and reduced mononuclear cell phagocytosis. Altogether, our data demonstrate that acute social stress alters immune competence of piglets from both groups, and bring new insights in favour of good farming practices. While for most parameters high- and low-responders to ACTH behaved similarly, HPA hi piglets displayed higher number of CD4 + CD8α - T cells, as well as increased cytokine production in WBA (LPS-induced TNFα and PIL-induced IL-8), which could confer them increased resistance to pathogens. Finally, a principal component analysis including all parameters

  14. Acute stress in adulthood impoverishes social choices and triggers aggressiveness in preclinical models.

    PubMed

    Nosjean, Anne; Cressant, Arnaud; de Chaumont, Fabrice; Olivo-Marin, Jean-Christophe; Chauveau, Frédéric; Granon, Sylvie

    2014-01-01

    Adult C57BL/6J mice are known to exhibit high level of social flexibility while mice lacking the β2 subunit of nicotinic receptors (β2(-/-) mice) present social rigidity. We asked ourselves what would be the consequences of a restraint acute stress (45 min) on social interactions in adult mice of both genotypes, hence the contribution of neuronal nicotinic receptors in this process. We therefore dissected social interaction complexity of stressed and not stressed dyads of mice in a social interaction task. We also measured plasma corticosterone levels in our experimental conditions. We showed that a single stress exposure occurring in adulthood reduced and disorganized social interaction complexity in both C57BL/6J and β2(-/-) mice. These stress-induced maladaptive social interactions involved alteration of distinct social categories and strategies in both genotypes, suggesting a dissociable impact of stress depending on the functioning of the cholinergic nicotinic system. In both genotypes, social behaviors under stress were coupled to aggressive reactions with no plasma corticosterone changes. Thus, aggressiveness appeared a general response independent of nicotinic function. We demonstrate here that a single stress exposure occurring in adulthood is sufficient to impoverish social interactions: stress impaired social flexibility in C57BL/6J mice whereas it reinforced β2(-/-) mice behavioral rigidity.

  15. Acute stress in adulthood impoverishes social choices and triggers aggressiveness in preclinical models

    PubMed Central

    Nosjean, Anne; Cressant, Arnaud; de Chaumont, Fabrice; Olivo-Marin, Jean-Christophe; Chauveau, Frédéric; Granon, Sylvie

    2015-01-01

    Adult C57BL/6J mice are known to exhibit high level of social flexibility while mice lacking the β2 subunit of nicotinic receptors (β2−/− mice) present social rigidity. We asked ourselves what would be the consequences of a restraint acute stress (45 min) on social interactions in adult mice of both genotypes, hence the contribution of neuronal nicotinic receptors in this process. We therefore dissected social interaction complexity of stressed and not stressed dyads of mice in a social interaction task. We also measured plasma corticosterone levels in our experimental conditions. We showed that a single stress exposure occurring in adulthood reduced and disorganized social interaction complexity in both C57BL/6J and β2−/− mice. These stress-induced maladaptive social interactions involved alteration of distinct social categories and strategies in both genotypes, suggesting a dissociable impact of stress depending on the functioning of the cholinergic nicotinic system. In both genotypes, social behaviors under stress were coupled to aggressive reactions with no plasma corticosterone changes. Thus, aggressiveness appeared a general response independent of nicotinic function. We demonstrate here that a single stress exposure occurring in adulthood is sufficient to impoverish social interactions: stress impaired social flexibility in C57BL/6J mice whereas it reinforced β2−/− mice behavioral rigidity. PMID:25610381

  16. The Additive Benefit of Hypnosis and Cognitive-Behavioral Therapy in Treating Acute Stress Disorder

    ERIC Educational Resources Information Center

    Bryant, Richard A.; Moulds, Michelle L.; Guthrie, Rachel M.; Nixon, Reginald D. V.

    2005-01-01

    This research represents the first controlled treatment study of hypnosis and cognitive- behavioral therapy (CBT) of acute stress disorder (ASD). Civilian trauma survivors (N = 87) who met criteria for ASD were randomly allocated to 6 sessions of CBT, CBT combined with hypnosis (CBT-hypnosis), or supportive counseling (SC). CBT comprised exposure,…

  17. Modification of hippocampal markers of synaptic plasticity by memantine in animal models of acute and repeated restraint stress: implications for memory and behavior.

    PubMed

    Amin, Shaimaa Nasr; El-Aidi, Ahmed Amro; Ali, Mohamed Mostafa; Attia, Yasser Mahmoud; Rashed, Laila Ahmed

    2015-06-01

    Stress is any condition that impairs the balance of the organism physiologically or psychologically. The response to stress involves several neurohormonal consequences. Glutamate is the primary excitatory neurotransmitter in the central nervous system, and its release is increased by stress that predisposes to excitotoxicity in the brain. Memantine is an uncompetitive N-methyl D-aspartate glutamatergic receptors antagonist and has shown beneficial effect on cognitive function especially in Alzheimer's disease. The aim of the work was to investigate memantine effect on memory and behavior in animal models of acute and repeated restraint stress with the evaluation of serum markers of stress and the expression of hippocampal markers of synaptic plasticity. Forty-two male rats were divided into seven groups (six rats/group): control, acute restraint stress, acute restraint stress with Memantine, repeated restraint stress, repeated restraint stress with Memantine and Memantine groups (two subgroups as positive control). Spatial working memory and behavior were assessed by performance in Y-maze. We evaluated serum cortisol, tumor necrotic factor, interleukin-6 and hippocampal expression of brain-derived neurotrophic factor, synaptophysin and calcium-/calmodulin-dependent protein kinase II. Our results revealed that Memantine improved spatial working memory in repeated stress, decreased serum level of stress markers and modified the hippocampal synaptic plasticity markers in both patterns of stress exposure; in ARS, Memantine upregulated the expression of synaptophysin and brain-derived neurotrophic factor and downregulated the expression of calcium-/calmodulin-dependent protein kinase II, and in repeated restraint stress, it upregulated the expression of synaptophysin and downregulated calcium-/calmodulin-dependent protein kinase II expression.

  18. Divergent short- and long-term effects of acute stress in object recognition memory are mediated by endogenous opioid system activation.

    PubMed

    Nava-Mesa, Mauricio O; Lamprea, Marisol R; Múnera, Alejandro

    2013-11-01

    Acute stress induces short-term object recognition memory impairment and elicits endogenous opioid system activation. The aim of this study was thus to evaluate whether opiate system activation mediates the acute stress-induced object recognition memory changes. Adult male Wistar rats were trained in an object recognition task designed to test both short- and long-term memory. Subjects were randomly assigned to receive an intraperitoneal injection of saline, 1 mg/kg naltrexone or 3 mg/kg naltrexone, four and a half hours before the sample trial. Five minutes after the injection, half the subjects were submitted to movement restraint during four hours while the other half remained in their home cages. Non-stressed subjects receiving saline (control) performed adequately during the short-term memory test, while stressed subjects receiving saline displayed impaired performance. Naltrexone prevented such deleterious effect, in spite of the fact that it had no intrinsic effect on short-term object recognition memory. Stressed subjects receiving saline and non-stressed subjects receiving naltrexone performed adequately during the long-term memory test; however, control subjects as well as stressed subjects receiving a high dose of naltrexone performed poorly. Control subjects' dissociated performance during both memory tests suggests that the short-term memory test induced a retroactive interference effect mediated through light opioid system activation; such effect was prevented either by low dose naltrexone administration or by strongly activating the opioid system through acute stress. Both short-term memory retrieval impairment and long-term memory improvement observed in stressed subjects may have been mediated through strong opioid system activation, since they were prevented by high dose naltrexone administration. Therefore, the activation of the opioid system plays a dual modulating role in object recognition memory. Copyright © 2013 Elsevier Inc. All rights

  19. Changes in the levels of p-ERK, p-CREB, and c-fos in rat mesocorticolimbic dopaminergic system after morphine-induced conditioned place preference: the role of acute and subchronic stress.

    PubMed

    Haghparast, Abbas; Fatahi, Zahra; Alamdary, Shabnam Zeighamy; Reisi, Zahra; Khodagholi, Fariba

    2014-03-01

    ERK pathway plays a critical role in the cellular adaptive responses to environmental changes. Stressful conditions can induce the activation of activate ERK, and its downstream targets, CREB and c-fos, in neural cells. Exposure to opioids has the same effect. In this study, we investigated the effects of morphine-induced conditioned place preference (CPP) on p-ERK/ERK ratio, p-CREB/CREB ratio and c-fos level in the mesocorticolimbic dopaminergic system including the nucleus accumbens (NAc), amygdala (AMY), striatum (Str), and prefrontal cortex (PFC).Our aim was to determine if acute and subchronic stress would affect these alterations. Male Wistar rats were divided into two saline- and morphine-treated groups. Each group contained of control, acute stress, and subchronic stress subgroups. The CPP procedure was performed for all of the rats. We dissected out the NAc, AMY, Str, and PFC regions and measured the mentioned ratios and c-fos level by Western blot analysis. The results revealed that in saline-treated animals, all factors enhanced significantly after performing acute and subchronic stress while there was an exception in p-ERK/ERK ratio in the Str and PFC; the changes were not significant during acute stress. Conditioning score decreased after applying the subchronic but not acute stress. In morphine-treated animals, all factors were increased after application of acute and subchronic stress, and conditioning scores also decreased after stress. Our findings suggest that in saline- or morphine-treated animals, acute and subchronic stress increases p-ERK, p-CREB, and c-fos levels in the mesocorticolimbic system. It has been shown that morphine induces the enhancement of the mentioned factors; on the other hand, our result demonstrates that stress can amplify these changes.

  20. Impaired cardiac ischemic tolerance in spontaneously hypertensive rats is attenuated by adaptation to chronic and acute stress.

    PubMed

    Ravingerová, T; Bernátová, I; Matejíková, J; Ledvényiová, V; Nemčeková, M; Pecháňová, O; Tribulová, N; Slezák, J

    2011-01-01

    Chronic hypertension may have a negative impact on the myocardial response to ischemia. On the other hand, intrinsic ischemic tolerance may persist even in the pathologically altered hearts of hypertensive animals, and may be modified by short- or long-term adaptation to different stressful conditions. The effects of long-term limitation of living space (ie, crowding stress [CS]) and brief ischemia-induced stress on cardiac response to ischemia/reperfusion (I/R) injury are not yet fully characterized in hypertensive subjects. The present study was designed to test the influence of chronic and acute stress on the myocardial response to I/R in spontaneously hypertensive rats (SHR) compared with their effects in normotensive counterparts. In both groups, chronic, eight-week CS was induced by caging five rats per cage in cages designed for two rats (200 cm(2)/rat), while controls (C) were housed four to a cage in cages designed for six animals (480 cm(2)/rat). Acute stress was evoked by one cycle of I/R (5 min each, ischemic preconditioning) before sustained I/R in isolated Langendorff-perfused hearts of normotensive and SHR rats. At baseline conditions, the effects of CS were manifested only as a further increase in blood pressure in SHR, and by marked limitation of coronary perfusion in normotensive animals, while no changes in heart mechanical function were observed in any of the groups. Postischemic recovery of contractile function, severity of ventricular arrhythmias and lethal injury (infarction size) were worsened in the hypertrophied hearts of C-SHR compared with normotensive C. However, myo-cardial stunning and reperfusion-induced ventricular arrhythmias were attenuated by CS in SHR, which was different from deterioration of I/R injury in the hearts of normotensive animals. In contrast, ischemic preconditioning conferred an effective protection against I/R in both groups, although the extent of anti-infarct and anti-arrhythmic effects was lower in SHR. Both

  1. Functional capacities of blood neurtrophils are influenced by both acute and chronic dexamethasone stress models in beef steers

    USDA-ARS?s Scientific Manuscript database

    This study investigated the effects of acute and chronic stress models on the functional capacity of blood neutrophils in beef steers. Steers (N=32; 209 +/- 8 kg) were blocked by BW and assigned to 1 of 3 treatments: 1) Control (CON), no dexamethasone (DEX); 2) Chronic stress (CHR), 0.5 mg/kg BW DEX...

  2. First contact: acute stress reactions and experiences of emergency department consultations following an incident of intimate partner violence.

    PubMed

    Olive, Philippa

    2017-08-01

    The aim of this research was to explore women's emotional and affective responses following an incident of intimate partner violence experienced during emergency department attendances. A growing body of research has explored women's experiences of emergency departments following intimate partner violence still little remains known about the experience and impact of emotional and affective responses during these attendances. A descriptive qualitative design was used, underpinned theoretically by critical realism and postmodern complexity theory to attend to multiple, intersecting mechanisms that lie behind events and experiences. Semistructured interviews with six women who had attended an emergency department directly following an incident of intimate partner violence. Interview data were transcribed and thematically analysed in nvivo9 using a coding framework. There were three interconnected key findings. First, was the commonality of acute stress experiences among women attending an emergency department following partner violence, second was that these acute stress reactions negatively impacted women's consultations, and third was the need for specialist domestic violence services at the point of first contact to assist service users navigate an effective consultation. Acute stress reactions were an important feature of women's experiences of emergency department consultations following intimate partner violence. Attending to psychological first aid; providing a safe and quiet space; and affording access to specialist violence advocacy services at the point of first contact will limit harm and improve health consultation outcomes for this population. This research provides an account of emotional and affective responses experienced by women attending emergency departments following intimate partner violence and explicates how these acute stress reactions impacted their consultation. This research has relevance for practitioners in many first contact health

  3. Chronic stress induces a hyporeactivity of the autonomic nervous system in response to acute mental stressor and impairs cognitive performance in business executives.

    PubMed

    Teixeira, Renata Roland; Díaz, Miguel Mauricio; Santos, Tatiane Vanessa da Silva; Bernardes, Jean Tofoles Martins; Peixoto, Leonardo Gomes; Bocanegra, Olga Lucia; Neto, Morun Bernardino; Espindola, Foued Salmen

    2015-01-01

    The present study examined the incidence of chronic stress in business executives (109 subjects: 75 male and 34 female) and its relationship with cortisol levels, cognitive performance, and autonomic nervous system (ANS) reactivity after an acute mental stressor. Blood samples were collected from the subjects to measure cortisol concentration. After the sample collection, the subjects completed the Lipp Inventory of Stress Symptoms for Adults and the Stroop Color-Word Test to evaluate stress and cognitive performance levels, respectively. Saliva samples were collected prior to, immediately after, and five minutes after the test. The results revealed that 90.1% of the stressed subjects experienced stress phases that are considered chronic stress. At rest, the subjects with chronic stress showed higher cortisol levels, and no gender differences were observed. No differences were found between the stressed and non-stressed subjects regarding salivary amylase activity prior to test. Chronic stress also impaired performance on the Stroop test, which revealed higher rates of error and longer reaction times in the incongruent stimulus task independently of gender. For the congruent stimulus task of the Stroop test, the stressed males presented a higher rate of errors than the non-stressed males and a longer reaction time than the stressed females. After the acute mental stressor, the non-stressed male group showed an increase in salivary alpha-amylase activity, which returned to the initial values five minutes after the test; this ANS reactivity was not observed in the chronically stressed male subjects. The ANS responses of the non-stressed vs stressed female groups were not different prior to or after the Stroop test. This study is the first to demonstrate a blunted reactivity of the ANS when male subjects with chronic psychological stress were subjected to an acute mental stressor, and this change could contribute to impairments in cognitive performance.

  4. Chronic Stress Induces a Hyporeactivity of the Autonomic Nervous System in Response to Acute Mental Stressor and Impairs Cognitive Performance in Business Executives

    PubMed Central

    Teixeira, Renata Roland; Díaz, Miguel Mauricio; Santos, Tatiane Vanessa da Silva; Bernardes, Jean Tofoles Martins; Peixoto, Leonardo Gomes; Bocanegra, Olga Lucia; Neto, Morun Bernardino; Espindola, Foued Salmen

    2015-01-01

    The present study examined the incidence of chronic stress in business executives (109 subjects: 75 male and 34 female) and its relationship with cortisol levels, cognitive performance, and autonomic nervous system (ANS) reactivity after an acute mental stressor. Blood samples were collected from the subjects to measure cortisol concentration. After the sample collection, the subjects completed the Lipp Inventory of Stress Symptoms for Adults and the Stroop Color-Word Test to evaluate stress and cognitive performance levels, respectively. Saliva samples were collected prior to, immediately after, and five minutes after the test. The results revealed that 90.1% of the stressed subjects experienced stress phases that are considered chronic stress. At rest, the subjects with chronic stress showed higher cortisol levels, and no gender differences were observed. No differences were found between the stressed and non-stressed subjects regarding salivary amylase activity prior to test. Chronic stress also impaired performance on the Stroop test, which revealed higher rates of error and longer reaction times in the incongruent stimulus task independently of gender. For the congruent stimulus task of the Stroop test, the stressed males presented a higher rate of errors than the non-stressed males and a longer reaction time than the stressed females. After the acute mental stressor, the non-stressed male group showed an increase in salivary alpha-amylase activity, which returned to the initial values five minutes after the test; this ANS reactivity was not observed in the chronically stressed male subjects. The ANS responses of the non-stressed vs stressed female groups were not different prior to or after the Stroop test. This study is the first to demonstrate a blunted reactivity of the ANS when male subjects with chronic psychological stress were subjected to an acute mental stressor, and this change could contribute to impairments in cognitive performance. PMID:25807003

  5. Oxidative stress and inflammation: liver responses and adaptations to acute and regular exercise.

    PubMed

    Pillon Barcelos, Rômulo; Freire Royes, Luiz Fernando; Gonzalez-Gallego, Javier; Bresciani, Guilherme

    2017-02-01

    The liver is remarkably important during exercise outcomes due to its contribution to detoxification, synthesis, and release of biomolecules, and energy supply to the exercising muscles. Recently, liver has been also shown to play an important role in redox status and inflammatory modulation during exercise. However, while several studies have described the adaptations of skeletal muscles to acute and chronic exercise, hepatic changes are still scarcely investigated. Indeed, acute intense exercise challenges the liver with increased reactive oxygen species (ROS) and inflammation onset, whereas regular training induces hepatic antioxidant and anti-inflammatory improvements. Acute and regular exercise protocols in combination with antioxidant and anti-inflammatory supplementation have been also tested to verify hepatic adaptations to exercise. Although positive results have been reported in some acute models, several studies have shown an increased exercise-related stress upon liver. A similar trend has been observed during training: while synergistic effects of training and antioxidant/anti-inflammatory supplementations have been occasionally found, others reported a blunting of relevant adaptations to exercise, following the patterns described in skeletal muscles. This review discusses current data regarding liver responses and adaptation to acute and regular exercise protocols alone or combined with antioxidant and anti-inflammatory supplementation. The understanding of the mechanisms behind these modulations is of interest for both exercise-related health and performance outcomes.

  6. Dimethylglycine Provides Salt and Temperature Stress Protection to Bacillus subtilis

    PubMed Central

    Bashir, Abdallah; Hoffmann, Tamara; Smits, Sander H. J.

    2014-01-01

    Glycine betaine is a potent osmotic and thermal stress protectant of many microorganisms. Its synthesis from glycine results in the formation of the intermediates monomethylglycine (sarcosine) and dimethylglycine (DMG), and these compounds are also produced when it is catabolized. Bacillus subtilis does not produce sarcosine or DMG, and it cannot metabolize these compounds. Here we have studied the potential of sarcosine and DMG to protect B. subtilis against osmotic, heat, and cold stress. Sarcosine, a compatible solute that possesses considerable protein-stabilizing properties, did not serve as a stress protectant of B. subtilis. DMG, on the other hand, proved to be only moderately effective as an osmotic stress protectant, but it exhibited good heat stress-relieving and excellent cold stress-relieving properties. DMG is imported into B. subtilis cells primarily under osmotic and temperature stress conditions via OpuA, a member of the ABC family of transporters. Ligand-binding studies with the extracellular solute receptor (OpuAC) of the OpuA system showed that OpuAC possesses a moderate affinity for DMG, with a Kd value of approximate 172 μM; its Kd for glycine betaine is about 26 μM. Docking studies using the crystal structures of the OpuAC protein with the sulfur analog of DMG, dimethylsulfonioacetate, as a template suggest a model of how the DMG molecule can be stably accommodated within the aromatic cage of the OpuAC ligand-binding pocket. Collectively, our data show that the ability to acquire DMG from exogenous sources under stressful environmental conditions helps the B. subtilis cell to cope with growth-restricting osmotic and temperature challenges. PMID:24561588

  7. The Effects of Hemodynamic Shear Stress on Stemness of Acute Myelogenous Leukemia (AML)

    NASA Astrophysics Data System (ADS)

    Raddatz, Andrew; Triantafillu, Ursula; Kim, Yonghyun (John)

    2015-11-01

    Cancer stem cells (CSCs) have recently been identified as the root cause of tumors generated from cancer cell populations. This is because these CSCs are drug-resistant and have the ability to self-renew and differentiate. Current methods of culturing CSCs require much time and money, so cancer cell culture protocols, which maximize yield of CSCs are needed. It was hypothesized that the quantity of Acute myelogenous leukemia stem cells (LSCs) would increase after applying shear stress to the leukemia cells based on previous studies with breast cancer in bioreactors. The shear stress was applied by pumping the cells through narrow tubing to mimic the in vivo bloodstream environment. In support of the hypothesis, shear stress was found to increase the amount of LSCs in a given leukemia population. This work was supported by NSF REU Site Award 1358991.

  8. Effect of interface reaction and diffusion on stress-oxidation coupling at high temperature

    NASA Astrophysics Data System (ADS)

    Yue, Mengkun; Dong, Xuelin; Fang, Xufei; Feng, Xue

    2018-04-01

    High-temperature structural materials undergo oxidation during the service, and stress would generate in the oxide film. Understanding the coupling effect between stress and oxidation contributes to the understanding of material degradation and failure during the oxidation process. Here, we propose a model to investigative the coupling effect of stress and oxidation at high temperature by considering the three-stage oxidation process, where both the interface reaction and the diffusion process are present. The governing equations including the oxidation kinetics and stress equilibrium for isothermal oxidation under stress-oxidation coupling effect have been derived. The theory is validated by comparing with the experimental results of SiO2 grown on Si substrate. Results show that the coupling of stress and oxidation influences the growth of the oxide film by affecting all three stages of the oxidation process.

  9. Rising to the Challenge: Acute Stress Appraisals and Selection Centre Performance in Applicants to Postgraduate Specialty Training in Anaesthesia

    ERIC Educational Resources Information Center

    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…

  10. In utero heat stress increases postnatal core body temperature in pigs

    USDA-ARS?s Scientific Manuscript database

    In utero heat stress (IUHS) negatively impacts postnatal development, but how it alters future body temperature parameters and energetic metabolism is not well-understood. Objectives were to characterize future temperature indices and bioenergetic markers in pigs originating from differing in utero...

  11. Acute and subchronic toxicity of inhaled toluene in male Long Evans rats: oxidative stress markers in brain

    EPA Pesticide Factsheets

    Research interested in oxidative stress markers following exposure to VOCsThis dataset is associated with the following publication:Kodavanti , P., J. Royland , D.A. Moore-Smith, J. Beas, J. Richards , T. Beasley , P. Evansky , and P.J. Bushnell. Acute and Subchronic Toxicity of Inhaled Toluene in Male Long-Evans Rats: Oxidative Stress Markers in Brain. NEUROTOXICOLOGY. Elsevier B.V., Amsterdam, NETHERLANDS, 51: 10-19, (2015).

  12. Cumulative Adversity Sensitizes Neural Response to Acute Stress: Association with Health Symptoms

    PubMed Central

    Seo, Dongju; Tsou, Kristen A; Ansell, Emily B; Potenza, Marc N; Sinha, Rajita

    2014-01-01

    Cumulative adversity (CA) increases stress sensitivity and risk of adverse health outcomes. However, neural mechanisms underlying these associations in humans remain unclear. To understand neural responses underlying the link between CA and adverse health symptoms, the current study assessed brain activity during stress and neutral-relaxing states in 75 demographically matched, healthy individuals with high, mid, and low CA (25 in each group), and their health symptoms using the Cornell Medical Index. CA was significantly associated with greater adverse health symptoms (P=0.01) in all participants. Functional magnetic resonance imaging results indicated significant associations between CA scores and increased stress-induced activity in the lateral prefrontal cortex, insula, striatum, right amygdala, hippocampus, and temporal regions in all 75 participants (p<0.05, whole-brain corrected). In addition to these regions, the high vs low CA group comparison revealed decreased stress-induced activity in the medial orbitofrontal cortex (OFC) in the high CA group (p<0.01, whole-brain corrected). Specifically, hypoactive medial OFC and hyperactive right hippocampus responses to stress were each significantly associated with greater adverse health symptoms (p<0.01). Furthermore, an inverse correlation was found between activity in the medial OFC and right hippocampus (p=0.01). These results indicate that high CA sensitizes limbic–striatal responses to acute stress and also identifies an important role for stress-related medial OFC and hippocampus responses in the effects of CA on increasing vulnerability to adverse health consequences. PMID:24051900

  13. Cumulative adversity sensitizes neural response to acute stress: association with health symptoms.

    PubMed

    Seo, Dongju; Tsou, Kristen A; Ansell, Emily B; Potenza, Marc N; Sinha, Rajita

    2014-02-01

    Cumulative adversity (CA) increases stress sensitivity and risk of adverse health outcomes. However, neural mechanisms underlying these associations in humans remain unclear. To understand neural responses underlying the link between CA and adverse health symptoms, the current study assessed brain activity during stress and neutral-relaxing states in 75 demographically matched, healthy individuals with high, mid, and low CA (25 in each group), and their health symptoms using the Cornell Medical Index. CA was significantly associated with greater adverse health symptoms (P=0.01) in all participants. Functional magnetic resonance imaging results indicated significant associations between CA scores and increased stress-induced activity in the lateral prefrontal cortex, insula, striatum, right amygdala, hippocampus, and temporal regions in all 75 participants (p<0.05, whole-brain corrected). In addition to these regions, the high vs low CA group comparison revealed decreased stress-induced activity in the medial orbitofrontal cortex (OFC) in the high CA group (p<0.01, whole-brain corrected). Specifically, hypoactive medial OFC and hyperactive right hippocampus responses to stress were each significantly associated with greater adverse health symptoms (p<0.01). Furthermore, an inverse correlation was found between activity in the medial OFC and right hippocampus (p=0.01). These results indicate that high CA sensitizes limbic-striatal responses to acute stress and also identifies an important role for stress-related medial OFC and hippocampus responses in the effects of CA on increasing vulnerability to adverse health consequences.

  14. Dark chocolate attenuates intracellular pro-inflammatory reactivity to acute psychosocial stress in men: A randomized controlled trial.

    PubMed

    Kuebler, Ulrike; Arpagaus, Angela; Meister, Rebecca E; von Känel, Roland; Huber, Susanne; Ehlert, Ulrike; Wirtz, Petra H

    2016-10-01

    Flavanol-rich dark chocolate consumption relates to lower risk of cardiovascular mortality, but underlying mechanisms are elusive. We investigated the effect of acute dark chocolate consumption on inflammatory measures before and after stress. Healthy men, aged 20-50years, were randomly assigned to a single intake of either 50g of flavanol-rich dark chocolate (n=31) or 50g of optically identical flavanol-free placebo-chocolate (n=34). Two hours after chocolate intake, both groups underwent the 15-min Trier Social Stress Test. We measured DNA-binding-activity of the pro-inflammatory transcription factor NF-κB (NF-κB-BA) in peripheral blood mononuclear cells, as well as plasma and whole blood mRNA levels of the pro-inflammatory cytokines IL-1β and IL-6, and the anti-inflammatory cytokine IL-10, prior to chocolate intake as well as before and several times after stress. We also repeatedly measured the flavanol epicatechin and the stress hormones epinephrine and cortisol in plasma and saliva, respectively. Compared to the placebo-chocolate-group, the dark-chocolate-group revealed a marginal increase in IL-10 mRNA prior to stress (p=0.065), and a significantly blunted stress reactivity of NF-κB-BA, IL-1β mRNA, and IL-6 mRNA (p's⩽0.036) with higher epicatechin levels relating to lower pro-inflammatory stress reactivity (p's⩽0.033). Stress hormone changes to stress were controlled. None of the other measures showed a significant chocolate effect (p's⩾0.19). Our findings indicate that acute flavanol-rich dark chocolate exerts anti-inflammatory effects both by increasing mRNA expression of the anti-inflammatory cytokine IL-10 and by attenuating the intracellular pro-inflammatory stress response. This mechanism may add to beneficial effects of dark chocolate on cardiovascular health. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Cooccurrence of and remission from general anxiety, depression, and posttraumatic stress disorder symptoms after acute lung injury: a 2-year longitudinal study.

    PubMed

    Bienvenu, O Joseph; Colantuoni, Elizabeth; Mendez-Tellez, Pedro A; Shanholtz, Carl; Dennison-Himmelfarb, Cheryl R; Pronovost, Peter J; Needham, Dale M

    2015-03-01

    To evaluate the cooccurrence, and predictors of remission, of general anxiety, depression, and posttraumatic stress disorder symptoms during 2-year follow-up in survivors of acute lung injury treated in an ICU. Prospective cohort study, with follow-up at 3, 6, 12, and 24 months post-acute lung injury. Thirteen medical and surgical ICUs in four hospitals. Survivors among 520 patients with acute lung injury. The outcomes of interest were measured using the Hospital Anxiety and Depression Scale anxiety and depression subscales (scores ≥ 8 indicating substantial symptoms) and the Impact of Event Scale-Revised (scores ≥ 1.6 indicating substantial posttraumatic stress disorder symptoms). Of the 520 enrolled patients, 274 died before 3-month follow-up; 186 of 196 consenting survivors (95%) completed at least one Hospital Anxiety and Depression Scale and Impact of Event Scale-Revised assessment during 2-year follow-up, and most completed multiple assessments. Across follow-up time points, the prevalence of suprathreshold general anxiety, depression, and posttraumatic stress disorder symptoms ranged from 38% to 44%, 26% to 33%, and 22% to 24%, respectively; more than half of the patients had suprathreshold symptoms in at least one domain during 2-year follow-up. The majority of survivors (59%) with any suprathreshold symptoms were above threshold for two or more types of symptoms (i.e., general anxiety, depression, and/or posttraumatic stress disorder). In fact, the most common pattern involved simultaneous general anxiety, depression, and posttraumatic stress disorder symptoms. Most patients with general anxiety, depression, or posttraumatic stress disorder symptoms during 2-year follow-up had suprathreshold symptoms at 24-month (last) follow-up. Higher Short-Form-36 physical functioning domain scores at the prior visit were associated with a greater likelihood of remission from general anxiety and posttraumatic stress disorder symptoms during follow-up. The majority

  16. Differential Effects of Acute Stress on Anticipatory and Consummatory Phases of Reward Processing

    PubMed Central

    Kumar, Poornima; Berghorst, Lisa H.; Nickerson, Lisa D.; Dutra, Sunny J.; Goer, Franziska; Greve, Douglas; Pizzagalli, Diego A.

    2014-01-01

    Anhedonia is one of the core symptoms of depression and has been linked to blunted responses to rewarding stimuli in striatal regions. Stress, a key vulnerability factor for depression, has been shown to induce anhedonic behavior, including reduced reward responsiveness in both animals and humans, but the brain processes associated with these effects remain largely unknown in humans. Emerging evidence suggests that stress has dissociable effects on distinct components of reward processing, as it has been found to potentiate motivation/‘wanting’ during the anticipatory phase but reduce reward responsiveness/‘liking’ during the consummatory phase. To examine the impact of stress on reward processing, we used a monetary incentive delay (MID) task and an acute stress manipulation (negative performance feedback) in conjunction with functional magnetic resonance imaging (fMRI). Fifteen healthy participants performed the MID task under no-stress and stress conditions. We hypothesized that stress would have dissociable effects on the anticipatory and consummatory phases in reward-related brain regions. Specifically, we expected reduced striatal responsiveness during reward consumption (mirroring patterns previously observed in clinical depression) and increased striatal activation during reward anticipation consistent with non-human findings. Supporting our hypotheses, significant Phase (Anticipation/Consumption) x Stress (Stress/No-stress) interactions emerged in the putamen, nucleus accumbens, caudate and amygdala. Post-hoc tests revealed that stress increased striatal and amygdalar activation during anticipation but decreased striatal activation during consumption. Importantly, stress-induced striatal blunting was similar to the profile observed in clinical depression under baseline (no-stress) conditions in prior studies. Given that stress is a pivotal vulnerability factor for depression, these results offer insight to better understand the etiology of this

  17. The impact of acute psychosocial stress on magnetoencephalographic correlates of emotional attention and exogenous visual attention.

    PubMed

    Elling, Ludger; Schupp, Harald; Bayer, Janine; Bröckelmann, Ann-Kathrin; Steinberg, Christian; Dobel, Christian; Junghofer, Markus

    2012-01-01

    Stress-induced acute activation of the cerebral catecholaminergic systems has often been found in rodents. However, little is known regarding the consequences of this activation on higher cognitive functions in humans. Theoretical inferences would suggest increased distractibility in the sense of increased exogenous attention and emotional attention. The present study investigated the influence of acute stress responses on magnetoencephalographic (MEG) correlates of visual attention. Healthy male subjects were presented emotional and neutral pictures in three subsequent MEG recording sessions after being exposed to a TSST-like social stressor, intended to trigger a HPA-response. The subjects anticipation of another follow-up stressor was designed to sustain the short-lived central catecholaminergic stress reactions throughout the ongoing MEG recordings. The heart rate indicates a stable level of anticipatory stress during this time span, subsequent cortisol concentrations and self-report measures of stress were increased. With regard to the MEG correlates of attentional functions, we found that the N1m amplitude remained constantly elevated during stressor anticipation. The magnetic early posterior negativity (EPNm) was present but, surprisingly, was not at all modulated during stressor anticipation. This suggests that a general increase of the influence of exogenous attention but no specific effect regarding emotional attention in this time interval. Regarding the time course of the effects, an influence of the HPA on these MEG correlates of attention seems less likely. An influence of cerebral catecholaminergic systems is plausible, but not definite.

  18. Protective effect of Curcuma longa L. extract on CCl4-induced acute hepatic stress.

    PubMed

    Lee, Geum-Hwa; Lee, Hwa-Young; Choi, Min-Kyung; Chung, Han-Wool; Kim, Seung-Wook; Chae, Han-Jung

    2017-02-01

    The Curcuma longa L. (CLL) rhizome has long been used to treat patients with hepatic dysfunction. CLL is a member of the ginger family of spices that are widely used in China, India, and Japan, and is a common spice, coloring, flavoring, and traditional medicine. This study was performed to evaluate the hepatoprotective activity of CLL extract and its active component curcumin in an acute carbon tetrachloride (CCl 4 )-induced liver stress model. Acute hepatic stress was induced by a single intraperitoneal injection of CCl 4 (0.1 ml/kg body weight) in rats. CLL extract was administered once a day for 3 days at three dose levels (100, 200, and 300 mg/kg/day) and curcumin was administered once a day at the 200 mg/kg/day. We performed alanine transaminase (ALT) and aspartate transaminase (AST). activity analysis and also measured total lipid, triglyceride, and cholesterol levels, and lipid peroxidation. At 100 g CLL, the curcuminoid components curcumin (901.63 ± 5.37 mg/100 g), bis-demethoxycurcumin (108.28 ± 2.89 mg/100 g), and demethoxycurcumin (234.85 ± 1.85 mg/100 g) were quantified through high liquid chromatography analysis. In CCl 4 -treated rats, serum AST and ALT levels increased 2.1- and 1.2-fold compared with the control. AST but not ALT elevation induced by CCl 4 was significantly alleviated in CLL- and curcumin-treated rats. Peroxidation of membrane lipids in the liver was significantly prevented by CLL (100, 200, and 300 mg/kg/day) on tissue lipid peroxidation assay and immunostaining with anti-4HNE antibody. We found that CLL extract and curcumin exhibited significant protection against liver injury by improving hepatic superoxide dismutase (p < 0.05) and glutathione peroxidase activity, and glutathione content in the CCl 4 -treated group (p < 0.05), leading to a reduced lipid peroxidase level. Our data suggested that CLL extract and curcumin protect the liver from acute CCl 4 -induced injury in a rodent model by suppressing

  19. A longitudinal fMRI investigation in acute post-traumatic stress disorder (PTSD).

    PubMed

    Ke, Jun; Zhang, Li; Qi, Rongfeng; Li, Weihui; Hou, Cailan; Zhong, Yuan; He, Zhong; Li, Lingjiang; Lu, Guangming

    2016-11-01

    Background Neuroimaging studies have implicated limbic, paralimbic, and prefrontal cortex in the pathophysiology of chronic post-traumatic stress disorder (PTSD). However, little is known about the neural substrates of acute PTSD and how they change with symptom improvement. Purpose To examine the neural circuitry underlying acute PTSD and brain function changes during clinical recovery from this disorder. Material and Methods Nineteen acute PTSD patients and nine non-PTSD subjects who all experienced a devastating mining accident underwent clinical assessment as well as functional magnetic resonance imaging (fMRI) scanning while viewing trauma-related and neutral pictures. Two years after the accident, a subgroup of 17 patients completed a second clinical evaluation, of which 13 were given an identical follow-up scan. Results Acute PTSD patients demonstrated greater activation in the vermis and right posterior cingulate, and greater deactivation in the bilateral medial prefrontal cortex and inferior parietal lobules than controls in the traumatic versus neutral condition. At follow-up, PTSD patients showed symptom reduction and decreased activation in the right middle frontal gyrus, bilateral posterior cingulate/precuneus, and cerebellum. Correlation results confirmed these findings and indicated that brain activation in the posterior cingulate/precuneus and vermis was predictive of PTSD symptom improvement. Conclusion The findings support the involvement of the medial prefrontal cortex, inferior parietal lobule, posterior cingulate, and vermis in the pathogenesis of acute PTSD. Brain activation in the vermis and posterior cingulate/precuneus appears to be a biological marker of recovery potential from PTSD. Furthermore, decreased activation of the middle frontal gyrus, posterior cingulate/precuneus, and cerebellum may reflect symptom improvement.

  20. Boron application improves yield of rice cultivars under high temperature stress during vegetative and reproductive stages.

    PubMed

    Shahid, Mohammad; Nayak, Amaresh Kumar; Tripathi, Rahul; Katara, Jawahar Lal; Bihari, Priyanka; Lal, Banwari; Gautam, Priyanka

    2018-04-12

    It is reported that high temperatures (HT) would cause a marked decrease in world rice production. In tropical regions, high temperatures are a constraint to rice production and the most damaging effect is on spikelet sterility. Boron (B) plays a very important role in the cell wall formation, sugar translocation, and reproduction of the rice crop and could play an important role in alleviating high temperature stress. A pot culture experiment was conducted to study the effect of B application on high temperature tolerance of rice cultivars in B-deficient soil. The treatments comprised of four boron application treatments viz. control (B0), soil application of 1 kg B ha -1 (B1), soil application of 2 kg B ha -1 (B2), and foliar spray of 0.2% B (Bfs); three rice cultivars viz. Annapurna (HT stress tolerant), Naveen, and Shatabdi (both HT stress susceptible); and three temperature regimes viz. ambient (AT), HT at vegetative stage (HTV), and HT at reproductive stage (HTR). The results revealed that high temperature stress during vegetative or flowering stage reduced grain yield of rice cultivars mainly because of low pollen viability and spikelet fertility. The effects of high temperature on the spikelet fertility and grain filling varied among cultivars and the growth stages of plant when exposed to the high temperature stress. Under high temperature stress, the tolerant cultivar displays higher cell membrane stability, less accumulation of osmolytes, more antioxidant enzyme activities, and higher pollen viability and spikelet fertility than the susceptible cultivars. In the present work, soil application of boron was effective in reducing the negative effects of high temperature both at vegetative and reproductive stages. Application of B results into higher grain yield under both ambient and high temperature condition over control for all the three cultivars; however, more increase was observed for the susceptible cultivar over the tolerant one. The results

  1. Boron application improves yield of rice cultivars under high temperature stress during vegetative and reproductive stages

    NASA Astrophysics Data System (ADS)

    Shahid, Mohammad; Nayak, Amaresh Kumar; Tripathi, Rahul; Katara, Jawahar Lal; Bihari, Priyanka; Lal, Banwari; Gautam, Priyanka

    2018-04-01

    It is reported that high temperatures (HT) would cause a marked decrease in world rice production. In tropical regions, high temperatures are a constraint to rice production and the most damaging effect is on spikelet sterility. Boron (B) plays a very important role in the cell wall formation, sugar translocation, and reproduction of the rice crop and could play an important role in alleviating high temperature stress. A pot culture experiment was conducted to study the effect of B application on high temperature tolerance of rice cultivars in B-deficient soil. The treatments comprised of four boron application treatments viz. control (B0), soil application of 1 kg B ha-1 (B1), soil application of 2 kg B ha-1 (B2), and foliar spray of 0.2% B (Bfs); three rice cultivars viz. Annapurna (HT stress tolerant), Naveen, and Shatabdi (both HT stress susceptible); and three temperature regimes viz. ambient (AT), HT at vegetative stage (HTV), and HT at reproductive stage (HTR). The results revealed that high temperature stress during vegetative or flowering stage reduced grain yield of rice cultivars mainly because of low pollen viability and spikelet fertility. The effects of high temperature on the spikelet fertility and grain filling varied among cultivars and the growth stages of plant when exposed to the high temperature stress. Under high temperature stress, the tolerant cultivar displays higher cell membrane stability, less accumulation of osmolytes, more antioxidant enzyme activities, and higher pollen viability and spikelet fertility than the susceptible cultivars. In the present work, soil application of boron was effective in reducing the negative effects of high temperature both at vegetative and reproductive stages. Application of B results into higher grain yield under both ambient and high temperature condition over control for all the three cultivars; however, more increase was observed for the susceptible cultivar over the tolerant one. The results suggest

  2. Comparative transcriptome profiling of Pyropia yezoensis (Ueda) M.S. Hwang & H.G. Choi in response to temperature stresses.

    PubMed

    Sun, Peipei; Mao, Yunxiang; Li, Guiyang; Cao, Min; Kong, Fanna; Wang, Li; Bi, Guiqi

    2015-06-17

    Pyropia yezoensis is a model organism often used to investigate the mechanisms underlying stress tolerance in intertidal zones. The digital gene expression (DGE) approach was used to characterize a genome-wide comparative analysis of differentially expressed genes (DEGs) that influence the physiological, developmental or biochemical processes in samples subjected to 4 treatments: high-temperature stress (HT), chilling stress (CS), freezing stress (FS) and normal temperature (NT). Equal amounts of total RNAs collected from 8 samples (two biological replicates per treatment) were sequenced using the Illumina/Solexa platform. Compared with NT, a total of 2202, 1334 and 592 differentially expressed unigenes were detected in HT, CS and FS respectively. Clustering analysis suggested P. yezoensis acclimates to low and high-temperature stress condition using different mechanisms: In heat stress, the unigenes related to replication and repair of DNA and protein processing in endoplasmic reticulum were active; however at low temperature stresses, unigenes related to carbohydrate metabolism and energy metabolism were active. Analysis of gene differential expression showed that four categories of DEGs functioning as temperature sensors were found, including heat shock proteins, H2A, histone deacetylase complex and transcription factors. Heat stress caused chloroplast genes down-regulated and unigenes encoding metacaspases up-regulated, which is an important regulator of PCD. Cold stress caused an increase in the expression of FAD to improve the proportion of polyunsaturated fatty acids. An up-regulated unigene encoding farnesyl pyrophosphate synthase was found in cold stress, indicating that the plant hormone ABA also played an important role in responding to temperature stress in P. yezoensis. The variation of amount of unigenes and different gene expression pattern under different temperature stresses indicated the complicated and diverse regulation mechanism in response to

  3. Hydrogen sulfide protects endothelial nitric oxide function under conditions of acute oxidative stress in vitro.

    PubMed

    Al-Magableh, Mohammad R; Kemp-Harper, Barbara K; Ng, Hooi H; Miller, Alyson A; Hart, Joanne L

    2014-01-01

    The aim of this study was to examine the ability of H2S, released from NaHS to protect vascular endothelial function under conditions of acute oxidative stress by scavenging superoxide anions (O2(-)) and suppressing vascular superoxide anion production. O2(-) was generated in Krebs' solution by reacting hypoxanthine with xanthine oxidase (Hx-XO) or with the O2(-) generator pyrogallol to model acute oxidative stress in vitro. O2(-) generation was measured by lucigenin-enhanced chemiluminescence. Functional responses in mouse aortic rings were assessed using a small vessel myograph. NaHS scavenged O2(-) in a concentration-dependent manner. Isolated aortic rings exposed to either Hx-XO or pyrogallol displayed significantly attenuated maximum vasorelaxation responses to the endothelium-dependent vasodilator acetylcholine, and significantly reduced NO bioavailability, which was completely reversed if vessels were pre-incubated with NaHS (100 μM). NADPH-stimulated aortic O2(-) production was significantly attenuated by the NADPH oxidase inhibitor diphenyl iodonium. Prior treatment of vessels with NaHS (100 nM-100 μM; 30 min) inhibited NADPH-stimulated aortic O2(-) production in a concentration-dependent manner. This effect persisted when NaHS was washed out prior to measuring NADPH-stimulated O2(-) production. These data show for the first time that NaHS directly scavenges O2(-) and suppresses vascular NADPH oxidase-derived O2(-) production in vitro. Furthermore, these properties protect endothelial function and NO bioavailability in an in vitro model of acute oxidative stress. These results suggest that H2S can elicit vasoprotection by both scavenging O2(-) and by reducing vascular NADPH oxidase-derived O2(-) production.

  4. Temperature factors effect on occurrence of stress corrosion cracking of main gas pipeline

    NASA Astrophysics Data System (ADS)

    Nazarova, M. N.; Akhmetov, R. R.; Krainov, S. A.

    2017-10-01

    The purpose of the article is to analyze and compare the data in order to contribute to the formation of an objective opinion on the issue of the growth of stress corrosion defects of the main gas pipeline. According to available data, a histogram of the dependence of defects due to stress corrosion on the distance from the compressor station was constructed, and graphs of the dependence of the accident density due to stress corrosion in the winter and summer were also plotted. Data on activation energy were collected and analyzed in which occurrence of stress corrosion is most likely constructed, a plot of activation energy versus temperature is plotted, and the process of occurrence of stress corrosion by the example of two different grades of steels under the action of different temperatures was analyzed.

  5. Possible GABAergic modulation in the protective effect of zolpidem in acute hypoxic stress-induced behavior alterations and oxidative damage.

    PubMed

    Kumar, Anil; Goyal, Richa

    2008-03-01

    Hypoxia is an environmental stressor that is known to elicit alterations in both the autonomic nervous system and endocrine functions. The free radical or oxidative stress theory holds that oxidative reactions are mainly underlying neurodegenerative disorders. In fact among complex metabolic reactions occurring during hypoxia, many could be related to the formation of oxygen derived free radicals, causing a wide spectrum of cell damage. In present study, we investigated possible involvement of GABAergic mechanism in the protective effect of zolpidem against acute hypoxia-induced behavioral modification and biochemical alterations in mice. Mice were subjected to acute hypoxic stress for a period of 2 h. Acute hypoxic stress for 2 h caused significant impairment in locomotor activity, anxiety-like behavior, and antinocioceptive effect in mice. Biochemical analysis revealed a significant increased malondialdehyde, nitrite concentrations and depleted reduced glutathione and catalase levels. Pretreatment with zolpidem (5 and 10 mg/kg, i.p.) significantly improved locomotor activity, anti-anxiety effect, reduced tail flick latency and attenuated oxidative damage (reduced malondialdehyde, nitrite concentration, and restoration of reduced glutathione and catalase levels) as compared to stressed control (hypoxia) (P < 0.05). Besides, protective effect of zolpidem (5 mg/kg) was blocked significantly by picrotoxin (1.0 mg/kg) or flumazenil (2 mg/kg) and potentiated by muscimol (0.05 mg/kg) in hypoxic animals (P < 0.05). These effects were significant as compared to zolpidem (5 mg/kg) per se (P < 0.05). Present study suggest that the possible involvement of GABAergic modulation in the protective effect of zolpidem against hypoxic stress.

  6. Schisandrin B alleviates acute oxidative stress via modulating Nrf2/Keap1-mediated antioxidant pathway.

    PubMed

    Ying, Wu; Li, Zheng-Cai; Li-Qing, Yao; Mai, Li; Mei, Tang

    2018-05-09

    Schisandrin B (Sch B), one of Fructus Schisandrae's main effective components, protects neurons from oxidative stress in the central nervous system. Here we investigated the neuroprotective effect of Sch B in the acute oxidative stress damage and attempted to define the possible mechanisms. From the elevated plus maze (EPM) and open field test (OFT), we found that forcing swimming, an acute stressor, significantly induced anxiety-like behavior which was alleviated by Sch B (p.o.) treatment. In addition, the Sch B treatment suppressed toxicity, malondialdehyde (MDA) and reactive oxygen species (ROS), an important factor for neuron damage. The antioxidant molecules under the control of Nrf2 pathway, such as superoxide dismutase (SOD) and glutathione (GSH), were significantly increased by Sch B treatment. Moreover, a higher percentage of intact cells in the amygdala further verified the neuroprotective effect of Sch B in Nissl staining. Several proteins such as Nrf2 and its endogenous inhibitor Keap1, were abnormal expressed in force swimming mice but were significantly reversed by Sch B treatment. Herein, our results suggested that Sch B may be a potential therapeutic agent against anxiety disease that is associated with oxidative stress. The possible mechanism is attributed to its neuroprotection through enhancing antioxidant effect.

  7. Stress and temperature dependence of screw dislocation mobility in {alpha}-Fe by molecular dynamics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gilbert, M. R.; Queyreau, S.; Marian, J.

    2011-11-01

    The low-temperature plastic yield of {alpha}-Fe single crystals is known to display a strong temperature dependence and to be controlled by the thermally activated motion of screw dislocations. In this paper, we present molecular dynamics simulations of (1/2)<111>{l_brace}112{r_brace} screw dislocation motion as a function of temperature and stress in order to extract mobility relations that describe the general dynamic behavior of screw dislocations in pure {alpha}-Fe. We find two dynamic regimes in the stress-velocity space governed by different mechanisms of motion. Consistent with experimental evidence, at low stresses and temperatures, the dislocations move by thermally activated nucleation and propagation ofmore » kink pairs. Then, at a critical stress, a temperature-dependent transition to a viscous linear regime is observed. Critical output from the simulations, such as threshold stresses and the stress dependence of the kink activation energy, are compared to experimental data and other atomistic works with generally very good agreement. Contrary to some experimental interpretations, we find that glide on {l_brace}112{r_brace} planes is only apparent, as slip always occurs by elementary kink-pair nucleation/propagation events on {l_brace}110{r_brace} planes. Additionally, a dislocation core transformation from compact to dissociated has been identified above room temperature, although its impact on the general mobility is seen to be limited. This and other observations expose the limitations of inferring or presuming dynamic behavior on the basis of only static calculations. We discuss the relevance and applicability of our results and provide a closed-form functional mobility law suitable for mesoscale computational techniques.« less

  8. Long-term and acute effects of temperature and oxygen on metabolism, food intake, growth and heat tolerance in a freshwater gastropod.

    PubMed

    Hoefnagel, K Natan; Verberk, Wilco C E P

    2017-08-01

    Temperature affects the physiology and life-history of ectothermic animals, often increasing metabolic rate and decreasing body size. Oxygen limitation has been put forward as a mechanism to explain thermal responses of body size and the ability to survive stress. However the time-scales involved in growth performance and heat tolerance differ radically. In order to increase our understanding of oxygen and temperature effects on body size and heat tolerance and the time scale involved, we reared Lymnaea stagnalis under six combinations of temperature and oxygen tension from hatching up to an age of 300 days and recorded shell length during this whole period. At the end of this period, we determined scope for growth by measuring food intake rate, assimilation efficiency, respiration rate and ammonium excretion rate at two different temperatures. We also measured the snails' ability to survive heat stress (CTmax), both at normoxia and hypoxia. We found that scope for growth and long term growth performance were much more affected by interactions of chronic oxygen and temperature conditions during rearing than by acute conditions during testing. Furthermore, our study shows that individual variation in growth performance can be traced back to individual differences in rates of food and oxygen consumption. Developmental acclimation also gave rise to differences in CTmax, but these were relatively small and were only expressed when CTmax was tested under hypoxia. The large effects of rearing oxygen conditions on growth and other physiological rates compared to modest effects of test oxygen conditions on CTmax suggest that small effects of hypoxia on the short term (e.g. heat tolerance) may nevertheless have large repercussions on the long term (e.g. growth and reproduction), even in a pulmonate snail that can compensate for hypoxia to some extent by aerial respiration. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Stress modulation of cellular metabolic sensors: interaction of stress from temperature and rainfall on the intertidal limpet Cellana toreuma.

    PubMed

    Dong, Yun-Wei; Han, Guo-Dong; Huang, Xiong-Wei

    2014-09-01

    In the natural environment, organisms are exposed to large variations in physical conditions. Quantifying such physiological responses is, however, often performed in laboratory acclimation studies, in which usually only a single factor is varied. In contrast, field acclimatization may expose organisms to concurrent changes in several environmental variables. The interactions of these factors may have strong effects on organismal function. In particular, rare events that occur stochastically and have relatively short duration may have strong effects. The present experiments studied levels of expression of several genes associated with cellular stress and metabolic regulation in a field population of limpet Cellana toreuma that encountered a wide range of temperatures plus periodic rain events. Physiological responses to these variable conditions were quantified by measuring levels of mRNA of genes encoding heat-shock proteins (Hsps) and metabolic sensors (AMPKs and Sirtuin 1). Our results reveal high ratios of individuals in upregulation group of stress-related gene expression at high temperature and rainy days, indicating the occurrence of stress from both prevailing high summer temperatures and occasional rainfall during periods of emersion. At high temperature, stress due to exposure to rainfall may be more challenging than heat stress alone. The highly variable physiological performances of limpets in their natural habitats indicate the possible differences in capability for physiological regulation among individuals. Our results emphasize the importance of studies of field acclimatization in unravelling the effects of environmental change on organisms, notably in the context of multiple changes in abiotic factors that are accompanying global change. © 2014 John Wiley & Sons Ltd.

  10. Psychosocial stress factors, including the relationship with the coach, and their influence on acute and overuse injury risk in elite female football players

    PubMed Central

    Pensgaard, Anne Marte; Ivarsson, Andreas; Nilstad, Agnethe; Solstad, Bård Erlend; Steffen, Kathrin

    2018-01-01

    Background The relationship between specific types of stressors (eg, teammates, coach) and acute versus overuse injuries is not well understood. Objective To examine the roles of different types of stressors as well as the effect of motivational climate on the occurrence of acute and overuse injuries. Methods Players in the Norwegian elite female football league (n=193 players from 12 teams) participated in baseline screening tests prior to the 2009 competitive football season. As part of the screening, we included the Life Event Survey for Collegiate Athletes and the Perceived Motivational Climate in Sport Questionnaire (Norwegian short version). Acute and overuse time-loss injuries and exposure to training and matches were recorded prospectively in the football season using weekly text messaging. Data were analysed with Bayesian logistic regression analyses. Results Using Bayesian logistic regression analyses, we showed that perceived negative life event stress from teammates was associated with an increased risk of acute injuries (OR=1.23, 95% credibility interval (1.01 to 1.48)). There was a credible positive association between perceived negative life event stress from the coach and the risk of overuse injuries (OR=1.21, 95% credibility interval (1.01 to 1.45)). Conclusions Players who report teammates as a source of stress have a greater risk of sustaining an acute injury, while players reporting the coach as a source of stress are at greater risk of sustaining an overuse injury. Motivational climate did not relate to increased injury occurrence. PMID:29629182

  11. Psychosocial stress factors, including the relationship with the coach, and their influence on acute and overuse injury risk in elite female football players.

    PubMed

    Pensgaard, Anne Marte; Ivarsson, Andreas; Nilstad, Agnethe; Solstad, Bård Erlend; Steffen, Kathrin

    2018-01-01

    The relationship between specific types of stressors (eg, teammates, coach) and acute versus overuse injuries is not well understood. To examine the roles of different types of stressors as well as the effect of motivational climate on the occurrence of acute and overuse injuries. Players in the Norwegian elite female football league (n=193 players from 12 teams) participated in baseline screening tests prior to the 2009 competitive football season. As part of the screening, we included the Life Event Survey for Collegiate Athletes and the Perceived Motivational Climate in Sport Questionnaire (Norwegian short version). Acute and overuse time-loss injuries and exposure to training and matches were recorded prospectively in the football season using weekly text messaging. Data were analysed with Bayesian logistic regression analyses. Using Bayesian logistic regression analyses, we showed that perceived negative life event stress from teammates was associated with an increased risk of acute injuries (OR=1.23, 95% credibility interval (1.01 to 1.48)). There was a credible positive association between perceived negative life event stress from the coach and the risk of overuse injuries (OR=1.21, 95% credibility interval (1.01 to 1.45)). Players who report teammates as a source of stress have a greater risk of sustaining an acute injury, while players reporting the coach as a source of stress are at greater risk of sustaining an overuse injury. Motivational climate did not relate to increased injury occurrence.

  12. Usefulness and limitation of dobutamine stress echocardiography to predict acute response to cardiac resynchronization therapy.

    PubMed

    Sénéchal, Mario; Lancellotti, Patrizio; Garceau, Patrick; Champagne, Jean; Dubois, Michelle; Magne, Julien; Blier, Louis; Molin, Frank; Philippon, François; Dumesnil, Jean G; Pierard, Luc; O'Hara, Gilles

    2010-01-01

    It has been hypothesized that a long-term response to cardiac resynchronization therapy (CRT) could correlate with myocardial viability in patients with left ventricular (LV) dysfunction. Contractile reserve and viability in the region of the pacing lead have not been investigated in regard to acute response after CRT. Fifty-one consecutive patients with advanced heart failure, LV ejection fraction 120 ms, and intraventricular asynchronism >or= 50 ms were prospectively included. The week before CRT implantation, the presence of viability was evaluated using dobutamine stress echocardiography. Acute responders were defined as a >or=15% increase in LV stroke volume. The average of viable segments was 5.8 +/- 1.9 in responders and 3.9 +/- 3 in nonresponders (P = 0.03). Viability in the region of the pacing lead had an excellent sensitivity (96%), but a low specificity (56%) to predict acute response to CRT. Mitral regurgitation (MR) was reduced in 21 patients (84%) with acute response. The presence of MR was a poor predictor of response (sensibility 93% and specificity 17%). However, combining the presence of MR and viability in the region of the pacing lead yields a sensibility (89%) and a specificity (70%) to predict acute response to CRT. Myocardial viability is an important factor influencing acute hemodynamic response to CRT. In acute responders, significant MR reduction is frequent. The combined presence of MR and viability in the region of the pacing lead predicts acute response to CRT with the best accuracy.

  13. On the determination of growth stress during oxidation of pure zirconium at elevated temperature

    NASA Astrophysics Data System (ADS)

    Kurpaska, L.; Favergeon, J.; Lahoche, L.; Moulin, G.

    2018-07-01

    An experimental approach have been proposed to evaluate growth of stress during high temperature oxidation of pure zirconium. The development of stress in the oxide scale has been investigated experimentally in in-situ conditions by combining the Deflection Test in Monofacial Oxidation (DTMO) with Acoustic Emission analysis (AE). Microstructure of the sample were studied by using Scanning Electron Microscopy technique. Oxidation experiments were performed continuously during 24 h at 400 °C and 500 °C in air under normal atmospheric pressure. Taking into account purely elastic behaviour of the material, primary evolution of growth stress developed in the oxide scale during oxidation process have been estimated. Presented study of the Zr/ZrO2 system revealed two opposite phenomena of stress relief when cooling from 400 °C and 500 °C to room temperature. This study is presented as a tool to understand the phenomena of stress evolution in the zirconia layer during isothermal treatment at high temperature and after cooling.

  14. ADRA2B genotype modulates effects of acute psychosocial stress on emotional memory retrieval in healthy young men.

    PubMed

    Li, Shijia; Weerda, Riklef; Guenzel, Friederike; Wolf, Oliver T; Thiel, Christiane M

    2013-07-01

    Previous studies have shown that acute psychosocial stress impairs retrieval of declarative memory with emotional material being especially sensitive to this effect. A functional deletion variant of the ADRA2B gene encoding the α2B-adrenergic receptor has been shown to increase emotional memory and neural activity in the amygdala. We investigated the effects of acute psychosocial stress and the ADRA2B allele on recognition memory for emotional and neutral faces. Fourty-two healthy, non-smoker male volunteers (30 deletion carriers, 12 noncarriers) were tested with a face recognition paradigm. During encoding they were presented with emotional and neutral faces. One hour later, participants underwent either a stress ("Trier Social Stress Test (TSST)") or a control procedure which was followed immediately by the retrieval session where subjects had to indicate whether the presented face was old or new. Stress increased salivary cortisol concentrations, blood pressure and pulse and impaired recognition memory for faces independent of emotional valence and genotype. Participants showed generally slower reaction times to emotional faces. Carriers of the ADRA2B functional deletion variant showed an impaired recognition and slower retrieval of neutral faces under stress. Further, they were significantly slower in retrieving fearful faces in the control condition. The findings indicate that a genetic variation of the noradrenergic system may preserve emotional faces from stress-induced memory impairments seen for neutral faces and heighten reactivity to emotional stimuli under control conditions. Copyright © 2013 Elsevier Inc. All rights reserved.

  15. Acute Stress Modulates Feedback Processing in Men and Women: Differential Effects on the Feedback-Related Negativity and Theta and Beta Power

    PubMed Central

    Banis, Stella; Geerligs, Linda; Lorist, Monicque M.

    2014-01-01

    Sex-specific prevalence rates in mental and physical disorders may be partly explained by sex differences in physiological stress responses. Neural networks that might be involved are those underlying feedback processing. Aim of the present EEG study was to investigate whether acute stress alters feedback processing, and whether stress effects differ between men and women. Male and female participants performed a gambling task, in a control and a stress condition. Stress was induced by exposing participants to a noise stressor. Brain activity was analyzed using both event-related potential and time-frequency analyses, measuring the feedback-related negativity (FRN) and feedback-related changes in theta and beta oscillatory power, respectively. While the FRN and feedback-related theta power were similarly affected by stress induction in both sexes, feedback-related beta power depended on the combination of stress induction condition and sex. FRN amplitude and theta power increases were smaller in the stress relative to the control condition in both sexes, demonstrating that acute noise stress impairs performance monitoring irrespective of sex. However, in the stress but not in the control condition, early lower beta-band power increases were larger for men than women, indicating that stress effects on feedback processing are partly sex-dependent. Our findings suggest that sex-specific effects on feedback processing may comprise a factor underlying sex-specific stress responses. PMID:24755943

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

    PubMed

    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

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

    PubMed

    Jimenez, Ana G; Williams, Joseph B

    2014-12-01

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

  18. Opposite Effects of Stress on Pain Modulation Depend on the Magnitude of Individual Stress Response.

    PubMed

    Geva, Nirit; Defrin, Ruth

    2018-04-01

    The effect of acute stress on pain threshold and intolerance threshold are reported as producing either hypoalgesia or hyperalgesia. Yet, the contribution of individual stress reactivity in this respect has not been established. The aim was to test 2 pain modulation paradigms under acute stress manipulation, to our knowledge, for the first time, to study whether stress differentially affects pain modulation, and whether the effect is related to individual stress response. Participants were 31 healthy subjects. Conditioned pain modulation (CPM) and pain adaptation were measured before and after inducing an acute stress response using the Montreal Imaging Stress Task. Subjects' stress response was evaluated according to salivary cortisol, autonomic function, and perceived stress and anxiety. The Montreal Imaging Stress Task induced a validated stress response. On a group level, stress induced reduction in CPM magnitude and increase in pain adaptation compared with baseline. These responses correlated with stress reactivity. When the group was subdivided according to stress reactivity, only high stress responders exhibited reduced CPM whereas only low stress responders exhibited increased pain adaptation. The results suggest that acute stress may induce opposite effects on pain modulation, depending on individual stress reactivity magnitude, with an advantage to low stress responders. This study evaluated the effect of acute stress on pain modulation. Pain modulation under stress is affected by individual stress responsiveness; decreased CPM occurs in high stress responders whereas increased pain adaptation occurs in low stress responders. Identification of high stress responders may promote better pain management. Copyright © 2017 The American Pain Society. Published by Elsevier Inc. All rights reserved.

  19. Acute hypoxia stress induced abundant differential expression genes and alternative splicing events in heart of tilapia.

    PubMed

    Xia, Jun Hong; Li, Hong Lian; Li, Bi Jun; Gu, Xiao Hui; Lin, Hao Ran

    2018-01-10

    Hypoxia is one of the critical environmental stressors for fish in aquatic environments. Although accumulating evidences indicate that gene expression is regulated by hypoxia stress in fish, how genes undergoing differential gene expression and/or alternative splicing (AS) in response to hypoxia stress in heart are not well understood. Using RNA-seq, we surveyed and detected 289 differential expressed genes (DEG) and 103 genes that undergo differential usage of exons and splice junctions events (DUES) in heart of a hypoxia tolerant fish, Nile tilapia, Oreochromis niloticus following 12h hypoxic treatment. The spatio-temporal expression analysis validated the significant association of differential exon usages in two randomly selected DUES genes (fam162a and ndrg2) in 5 tissues (heart, liver, brain, gill and spleen) sampled at three time points (6h, 12h, and 24h) under acute hypoxia treatment. Functional analysis significantly associated the differential expressed genes with the categories related to energy conservation, protein synthesis and immune response. Different enrichment categories were found between the DEG and DUES dataset. The Isomerase activity, Oxidoreductase activity, Glycolysis and Oxidative stress process were significantly enriched for the DEG gene dataset, but the Structural constituent of ribosome and Structural molecule activity, Ribosomal protein and RNA binding protein were significantly enriched only for the DUES genes. Our comparative transcriptomic analysis reveals abundant stress responsive genes and their differential regulation function in the heart tissues of Nile tilapia under acute hypoxia stress. Our findings will facilitate future investigation on transcriptome complexity and AS regulation during hypoxia stress in fish. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. Acute stress reduces speech fluency.

    PubMed

    Buchanan, Tony W; Laures-Gore, Jacqueline S; Duff, Melissa C

    2014-03-01

    People often report word-finding difficulties and other language disturbances when put in a stressful situation. There is, however, scant empirical evidence to support the claim that stress affects speech productivity. To address this issue, we measured speech and language variables during a stressful Trier Social Stress Test (TSST) as well as during a less stressful "placebo" TSST (Het et al., 2009). Compared to the non-stressful speech, participants showed higher word productivity during the TSST. By contrast, participants paused more during the stressful TSST, an effect that was especially pronounced in participants who produced a larger cortisol and heart rate response to the stressor. Findings support anecdotal evidence of stress-impaired speech production abilities. Copyright © 2014 Elsevier B.V. All rights reserved.