Relationship between acute stress and sleep disorder in grass-root military personnel:Mediating effect of social support

Background: To explore the relationship between acute stress, social support and sleep disorder in grass-root military personnel, and construct the relational model through structural equation modeling. Methods: A total of 2,411 grass-root military personnel were randomly selected by cluster sampling, and administered the Chinese Military Personnel Sleep Disorder Scale, Military Acute Stress Scale and Social Support Rating Scale.Results: The total score of acute stress scale was positively correlated with the total score and factor scores of sleep disorder scale(r=0.209~0.465, P【0.01); The total score of social support scale was positively correlated with the total score of acute stress scale and the total score and factor scores of sleep disorder scale(r=0.356~0.537, P【0.01). The analysis of mediating effects showed that lack of social support partially mediated between acute stress and the factors of sleep disorder. The analysis of structural equation model showed that acute stress not only had a direct effect on sleep disorder(the path coefficient was 0.29, P=0.000), but also on lack of social support(the path coefficient was 0.39, P=0.000); lack of social support had a direct effect on sleep disorder(the path coefficient was 0.48, P=0.000).Conclusions: Acute stress and lack of social support are two significant factors of sleep disorder in grass-root military personnel. Well-established social support could alleviate sleep disorder induced by acute stress. Lack of social support was a partial mediator between acute stress and sleep disorder.

Rapid Decrease and Subsequent Increase in the Serum Triglycerides Accompanied by CD36 Transcript Increase in an Acute Stress Mice Model

In this article, we report the changes in serum triglyceride (TG) levels that occurred during repeated tail blood sampling using a mouse restrainer. We used three groups of mice, namely, “PBS-restrained” “PBS-unrestrained” and “mock-restrained”. The mice in the PBS-restrained and PBS-unrestrained groups were intraperitoneally (i.p.) injected with 100 mL PBS and tail blood sampling was performed at 1, 5, 8, 24, and 48 h after i.p. injection. For the mock-restrained group, no i.p. injection was performed whereas the subsequent tail blood sampling was similarly performed. During the tail blood sampling, the mice of the two “restrained” groups were placed inside the restrainer designed from an open-ended 50 mL conical tube. The blood from the mice in the PBS-unrestrained group mice was sampled from the tail held by the operator’s hands while being allowed to move on a stage. Strikingly, in all of the three groups, the serum TG level initially decreased to remarkably low levels (approximately 30 mg/dL) after several blood samplings were performed over 8 h. This decrease was followed by a 2 - 3-fold increase in the levels relative to that in the control mice in the subsequent 24 - 48 h time period. We concluded that the acute stress associated with blood sampling caused alterations in TG levels. Serum levels of free fatty acid showed only modest changes. Changes in TG levels were not associated with serum corticosterone levels but with a dramatic increase in CD36 transcript levels in the liver. The relevance of this finding to the previously reported release of lipoprotein lipase (LPL) from white fatty tissue into the plasma during acute stress is also discussed.

Pancreatic Enzymes Activity under the Conditions of Acute Stress and Melanin Administration Depending on the Stress Resistance

Total proteolytic, antitrypsic, amylase and lypolytic activity was studied on animals subjected to acute stress simulation. Acute stress results in the development of imbalance of protease inhibitors potential as well as in the increase of amylase and lipase activity in the pancreas of the rats. Prior melanin administration in acute stress leads to a decrease in the activity of amylase and lipase, and an increase of total activity of protease inhibitors, that demonstrates stress-protective melanin effect produced on the pancreas.

Dip2a regulates stress susceptibility in the basolateral amygdala

Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post–traumatic stress disorder. Monoamines and amino acids are important types of neurotransmitters. Our previous results have shown that disco-interacting protein 2 homolog A(Dip2a) knockout mice exhibit brain development disorders and abnormal amino acid metabolism in serum. This suggests that DIP2A is involved in the metabolism of amino acid–associated neurotransmitters. Therefore, we performed targeted neurotransmitter metabolomics analysis and found that Dip2a deficiency caused abnormal metabolism of tryptophan and thyroxine in the basolateral amygdala and medial prefrontal cortex. In addition, acute restraint stress induced a decrease in 5-hydroxytryptamine in the basolateral amygdala. Additionally, Dip2a was abundantly expressed in excitatory neurons of the basolateral amygdala, and deletion of Dip2a in these neurons resulted in hopelessness-like behavior in the tail suspension test. Altogether, these findings demonstrate that DIP2A in the basolateral amygdala may be involved in the regulation of stress susceptibility. This provides critical evidence implicating a role of DIP2A in affective disorders.

Acute pancreatitis:The stress factor

Acute pancreatitis is an inflammatory disorder of the pancreas that may cause life-threatening complications.Etiologies of pancreatitis vary,with gallstones accounting for the majority of all cases,followed by alcohol.Other causes of pancreatitis include trauma,ischemia,mechanical obstruction,infections,autoimmune,hereditary,and drugs.The main events occurring in the pancreatic acinar cell that initiate and propagate acute pancreatitis include inhibition of secretion,intracellular activation of proteases,and generation of inflammatory mediators.Small cytokines known as chemokines are released from damaged pancreatic cells and attract inflammatory cells,whose systemic action ultimately determined the severity of the disease.Indeed,severe forms of pancreatitis may result in systemic inflammatory response syndrome and multiorgan dysfunction syndrome,characterized by a progressive physiologic failure of several interdependent organ systems.Stress occurs when homeostasis is threatened,and stressors can include physical or mental forces,or combinations of both.Depending on the timing and duration,stress can result in beneficial or harmful consequences.While it is well established that a previous acute-short-term stress decreases the severity of experimentally-induced pancreatitis,the worsening effects of chronic stress on the exocrine pancreas have received relatively little attention.This review will focus on the influence of both prior acute-short-term and chronic stress in acute pancreatitis.

Proteomic analysis of acute responses to copper sulfate stress in larvae of the brine shrimp,Artemia sinica

Proteomics was used to reveal the differential protein expression profiles of acute responses to copper sulfate exposure in larvae of Artemia sinica.Fourteen differentially displayed protein spots were detected and seven of them were identified.Three spots were up-expressed and identified:actin, heat shock protein 70,and chaperone subunit 1;three down-regulated proteins were identified:arginine kinase,elongation factor-2,and glycine-rich protein;and a newly expressed protein was identified as peroxiredoxin.The study indicates the involvement of all the differentially expressed proteins in the early responses of protein expression,and in the survival of A.sinica in the presence of copper and other heavy metals;the findings improve understanding of the organism’s adaptive responses and resistance.

Effect of Acute Low Temperature Stress on Oxygen Consumption Rate and Respiration Frequency in Silurus meridionalis and Pelteobag vachelli

The objective of the study was to explore the effect of acute low temperature stress on VO2 and Vf of Silurus meridionalis and Pelteobag vachelli after 10 minutes cold water bath with different temperature.The investigation was operated under the temperature of 24 ℃.It was found that the VO2 and Vf of Silurus meridionalis after 6 and 0 ℃ stress showed a decrease-increase-decrease trend while other groups showed a rapid increase then slowly recovery trend.The VO2 and Vf of Pelteobag vachelli after 0 ℃stress showed a decrease-increase-decrease trend while other groups showed an increase then slowly recovery process.It was suggested that Pelteobag vachelli was more adaptive to acute cold stress,but it cost more energy adapting to cold stress compared to Silurus meridionalis.

Alteration of cholinergic and peptidergic neurotransmitters in rat ileum induced by acute stress following transient intestinal infection is mast cell dependent

Background Mast cells are implicated in the development of irritable bowel syndrome （IBS）, which is associated with the activation of the ＂neural-immune＂ system. The aim of this study was to investigate the role of mast cells in the remodeling of cholinergic and peptidergic neurotransmitters induced by acute cold restriction stress （ACRS） post infection （PI） using mast cell deficient rats （Ws/Ws） and their wild-type controls （＋/＋）. Methods Transient intestinal infection was initiated by giving 1500 Trichinella spiralis （T.S.） larvae by gavage. ACRS was induced for 2 hours at day 100 PI. Samples of terminal ilea were prepared for H＆E staining, mast cell counting and activation and assessment of IL-113 and IL-10. Results When infected, both strains of rats experienced an acute infectious stage followed by a recovery. Histological scores were significantly higher in infected rats compared with those of the non-infected controls at day 10 PI （10 day-PI vs. control： ＋/＋： 2.75±0.17 vs. 0.42±0.09; Ws/Ws： 2.67±0.67 vs. 0.50±0.34; P 〈0.01）. In ＋/＋ rats, post-infection ACRS induced the formation of low-grade inflammation, represented by the imbalance of IL-1β and IL-10 （IL-1β： PI＋ACRS vs. control： （1812.24±561.61） vs. （1275.97±410.21） pg/g, P 〈0.05; IL-10： PI＋ACRS vs. control： （251.9±39.8） vs. （255.3±24.7） pg/g, P 〉0.05）, accompanied by hyperplasia and activation of mast cells （PI＋ACRS vs. control： 58.8±19.2 vs. 28.0±7.6; P 〈0.01）. The balance between acetylcholine （ACh） and substance P （SP） was also disturbed （ACh： PI＋ACRS vs. control： （743.94±238.72） vs. （1065.68±256.46） pg/g, P 〈0.05; SP： PI＋ACRS vs. control： （892.60±231.12） vs. （696.61±148.61） pg/g, P 〈0.05）. Nevertheless, similar changes of IL-1β/IL-10 and ACh/SP were not detected in Ws/Ws rats. Conclusion The imbalance of ACh/SP, together with the activation of mucosal immunity induced by post-infection ACRS were lacking in mast cell deficient rats, which supports the premise that mast cells play an important role in cholinergic and peptidergic remodeling in the ileum of rats.

Effects of Acute Temperature Stress on mRNA Expression of Transferrin in the Yellow Pond Turtle Mauremys mutica

The yellow pond turtle Mauremys mutica is widely cultured using both greenhouse-reared and outdoor pond-reared models.Individuals from the two models often show different tolerances to dramatic temperature changes caused by extreme weather events.However,the mechanism underlying the difference is unclear.In this study,we found that for greenhouse-reared turtles(GRTs),the expression levels of an immune-related gene for transferrin were significantly different(P<0.05)between the control group and the acute cold stress(ACS)group for most time points(3 h,6 h and 48 h),while at two time points(6 h and 12 h)there was a significant difference(P<0.05)between the control group and the acute heat stress(AHS)group.However,for the outdoor pond-reared turtles(OPTs),we found the opposite pattern:the ACS group showed no significant difference(P>0.05)from the control group for all time points(3 h,6 h,12 h,24 h and 48 h),whereas two time points(12 h and 24 h)were significantly different(P<0.05)for the AHS group.Our results indicate that ACS may influence the immunity of GRTs and have no influence on OPTs,whereas AHS may largely affect the immunity of OPTs and have little influence on GRTs.The findings provide insights into the mechanism underlying the different morbidity and mortality rates of turtles from different culture models after extreme weather events.

Fear of COVID-19 and emotional dysfunction problems:Intrusive,avoidance and hyperarousal stress as key mediators

BACKGROUND There is mounting empirical evidence of the detrimental effects of the coronavirus disease 2019(COVID-19)outbreak on mental health.Previous research has underscored the effects of similar destabilizing situations such as war,natural disasters or other pandemics on acute stress levels which have been shown to exacerbate current and future psychopathological symptoms.AIM To explore the role of acute stress responses(intrusive,avoidance and hyperarousal)as mediators in the association between fear of COVID-19 and emotional dysfunction-related problems:Depression,agoraphobia,panic,obsessivecompulsive,generalized anxiety,social anxiety and health anxiety symptoms.METHODS A sample of 439 participants from a university community in Spain(age:mean±SD:36.64±13.37;73.1%females)completed several measures assessing their fear of COVID-19,acute stress responses and emotional dysfunction syndromes through an online survey.Data collection was carried out from the start of home confinement in Spain until May 4,2020,coinciding with initial de-escalation measures.Processing of the dataset included descriptive and frequency analyses,Mann-Whitney U Test of intergroup comparisons and path analysis for direct and indirect effects.This is an observational,descriptive-correlational and crosssectional study.RESULTS The prevalence of clinical symptoms in our sample,reported since the beginning of the pandemic,reached 31.44%.The female group presented higher scores although the effect size was small.Overall,the participants who exceeded the clinical cut-off points in emotional problems showed higher levels of fear of COVID-19 and of cognitive,motor and psychophysiological responses of acute stress,unlike the group with normative scores.In addition,the results show significant mediated effects of hyperarousal stress among fear of COVID-19 and emotional dysfunction psychopathology.However,the clinical syndromes most related to the consequences of the pandemic(e.g.,social contact avoidance or frequent hand washing),such as agoraphobia and obsessive-compulsive symptoms,were in fact predicted directly by fear of COVID-19 and/or the acute stress response associated with the pandemic and had a greater predictive power.CONCLUSION The present study illustrates a clearer picture of the role of acute stress on several forms of psychopathology during the COVID-19 crisis and home confinement.

Aortic Stenosis and Stressed Heart Morphology

Myocardial geometric remodeling is a response to increased stress which includes increased afterload situations during clinical conditions. In this review, we have focused on early and late geometric features in aortic stenosis, importance of recognition of these findings and consequences due to progression of valve disease. We have also pointed out the similarities in early focal and global myocardial geometric remodeling in acute and chronic conditions as hypertension and acute stress cardiomypathy which are associated with myocardial functional and geometric response to acute or chronic stress exposure and relevant increased afterload. In aortic stenosis, target organ involvement in disease progression has been evaluated and discussed in the report. In addition to quantitative evaluation of valve disease, importance of myocardial involvement and global assessment of patients with aortic stenosis also have been mentioned in the report. Finally, we have discussed the importance of global myocardial geometric changes and timing for surgery before development of heart failure in this specific group of patients.

Effects of melatonin on the oxidative damage and pancreatic antioxidant defenses in ceruleininduced acute pancreatitis in rats

BACKGROUND： Oxidative stress is recognized as a pivotal effector of several pathogenic processes, including acute pancreatitis. Reactive oxygen species not just cause damage on the main cellular components, but also influence the expression of antioxidant system genes. Antioxidant molecules, such as melatonin, could be good candidates for the treatment of this multidimensional disease. The present study was to evaluate the chemopreventive effect of melatonin in a rat model of ceruleininduced acute pancreatitis.METHODS： Four subcutaneous injections of cerulein（20 μg/kg body weight） were given to Wistar rats at two hours intervals;melatonin was injected intraperitoneally（25 mg/kg body weight）30 minutes before each injection of cerulein. Lipid peroxidation,protein oxidation（carbonyl groups）, total antioxidant status,and glutathione peroxidase activity were determined in pancreatic tissue using commercial kits.RESULTS： The chemopreventive administration of melatonin caused a reduction in lipid peroxidation and protein oxidation due to injections of cerulein. Additionally, melatonin treatment was also able to revert glutathione peroxidase activity and total antioxidant status near to control levels, suggesting that melatonin could prevent from oxidative phenomena in the pancreas, such as lipid peroxidation and protein oxidation,and could stimulate, directly or indirectly, the expression of antioxidant enzymes.CONCLUSION： Melatonin, a polyvalent antioxidant, protected the pancreatic damage via the decrease of oxidative stress andincrease of the activities of antioxidant enzymes in ceruleininduced acute pancreatitis.

Neural and Behavioral Measures of Stress-induced Impairment in Error Awareness and Post-error Adjustment

Exposure to stress negatively affects error processing,but the impact of stress on error awareness remains to be determined.In the present study,we examined the temporal dynamics of error awareness and post-error adjustment following acute stress.Forty-nine healthy men were randomly assigned to the control(n=26)or stress group(n=23).After stress induction,participants completed the error awareness task,and their brain activity was assessed by electroencephalography.Compared to the control group,the stress group demonstrated lower error awareness accuracy and smaller Pe(error positivity)and ΔPe amplitudes following aware error responses,which indicated impairment of error awareness following stress.Furthermore,the stress group had lower accuracy in post-aware error responses than in post-unaware error responses and the control group,which indicated poor post-error adjustment following stress.Our results showed a stress effect on sequential stages of error processing.Stress induces impaired error identification,which further generates maladaptive post-error performance.

Factors influencing intercellular spaces in the rat esophageal epithelium

AIM:To evaluate the effect of acute stress,hydrochloric acid,ethanol,aspirin,and prednisolone on the intercellular spaces of the esophageal epithelium.METHODS:Part -RESULTS:(1) The f ive damaging factors produced no lesions or inflammation in esophageal mucosa of rats under either gross or routine histological inspections.Esophageal epithelial intercellular space diameters in stress and aspirin groups were significantly greater,nearly three or two-fold respectively,than those in their corresponding control groups (stress model:0.38 ± 0.05 μm vs 0.13 ± 0.02 μm,P < 0.01;aspirin model:0.32 ± 0.12 μm vs 0.19 ± 0.05 μm,P < 0.01).Neither intragastric administration of hydrochloric acid or ethanol,nor hypodermic injection of prednisolone produced DIS compared with their corresponding control groups (hydrochloric acid model:0.24 ± 0.03 μm vs 0.19 ± 0.05 μm,P > 0.05;ethanol model:0.25 ± 0.10 μm vs 0.19 ± 0.05 μm,P > 0.05;prednisolone model:0.20 ± 0.03 μm vs 0.14 ± 0.03 μm,P > 0.05);and (2) No significant difference in the intercellular space diameters was observed between the group pretreated with esomeprazole and the control group,in both the stress and aspirin models (stress model:0.35 ± 0.05 μm vs 0.37 ± 0.05 μm,P > 0.05;aspirin model:0.24 ± 0.02 μm vs 0.27 ± 0.03 μm,P > 0.05).CONCLUSION:Acute stress and aspirin can induce DIS of the esophageal epithelium in rats,and it is not correlated with acid reflux.

Commentary:Acute psychological stress redistributed leukocytes via distinct brain circuits

It is commonly known that psychological stress affects immunity through the nervous system,but the specific stress networks between brain and peripheral leukocytes,or their relationship with disease initiation or progression have yet to been delineated.A recent study by Poller and his colleagues1 propose an innovative perspective that distinct brain circuits rapidly manipulate a large-scale whole-body re-distribution of leukocytes(neutrophils,monocytes,lymphocytes)during psychological stress.

Distinct Effects of Social Stress on Working Memory in Obsessive-Compulsive Disorder

Stress might exaggerate the compulsion and impair the working memory of patients with obsessivecompulsive disorder(OCD). This study evaluated the effect of stress on the cognitive neural processing of working memory in OCD and its clinical significance using a ‘‘number calculation working memory'' task. Thirty-eight patients and 55 gender-and education-matched healthy controls were examined. Stress impaired the performance of the manipulation task in patients. Healthy controls showed less engagement of the medial prefrontal cortex and striatum during the task under stress versus less stress,which was absent in the patients with OCD. The diagnosis 9 stress interaction effect was significant in the right fusiform, supplementary motor area, precentral cortex and caudate. The failure of suppression of the medial prefrontal cortex and striatum and stress-related hyperactivation in the right fusiform, supplementary motor area, precentral cortex, and caudate might be an OCD-related psychopathological and neural response to stress.