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result(s) for
"Long-term stress"
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Evaluation of Hair Cortisol Concentration as a Biomarker of Long-Term Stress in Free-Ranging Polar Bears
by
David M. Janz
,
Kevin Middel
,
Bryan J. Macbeth
in
Body condition
,
body condition index
,
Conservation biology
2012
Long-term physiological stress in individual animals may be an important mechanism linking ecological change with impaired wildlife population health. In the Southern Hudson Bay (SH) subpopulation of polar bears (Ursus maritimus), increasing stress associated with climate warming may be related to declining body condition. Accordingly, the development of tools to assess long-term stress in this species may prove invaluable for conservation efforts in this threatened population. The measurement of hair cortisol concentration (HCC) has shown promise as a potential biomarker of long-term stress in free-ranging bears. However, to serve as a useful management tool, factors influencing HCC in polar bears must be identified and then revealed to establish linkages between environmental conditions and the fitness of individual animals. We determined HCC (median = 0.48 pg/mg [range = 0.16–2.26 pg/mg]) in 185 polar bears captured in southern Hudson Bay from 2007 to 2009. HCC was influenced by sex, family group status, and capture period but not by body region or hair type. Using models developed through a combination of hypothesis testing and information theory, we also determined that HCC was negatively associated with growth indices (length, mass, and body condition index) linked to fitness in polar bears. Additional research will be required across several polar bear populations to establish the utility of HCC as a tool for polar bear conservation.
Journal Article
EEG Based Classification of Long-Term Stress Using Psychological Labeling
by
Khalid, Humaira
,
Saeed, Sanay Muhammad Umar
,
Bagci, Ulas
in
Adult
,
Algorithms
,
Brain-Computer Interfaces
2020
Stress research is a rapidly emerging area in the field of electroencephalography (EEG) signal processing. The use of EEG as an objective measure for cost effective and personalized stress management becomes important in situations like the nonavailability of mental health facilities. In this study, long-term stress was classified with machine learning algorithms using resting state EEG signal recordings. The labeling for the stress and control groups was performed using two currently accepted clinical practices: (i) the perceived stress scale score and (ii) expert evaluation. The frequency domain features were extracted from five-channel EEG recordings in addition to the frontal and temporal alpha and beta asymmetries. The alpha asymmetry was computed from four channels and used as a feature. Feature selection was also performed to identify statistically significant features for both stress and control groups (via t-test). We found that support vector machine was best suited to classify long-term human stress when used with alpha asymmetry as a feature. It was observed that the expert evaluation-based labeling method had improved the classification accuracy by up to 85.20%. Based on these results, it is concluded that alpha asymmetry may be used as a potential bio-marker for stress classification, when labels are assigned using expert evaluation.
Journal Article
Long‐term spaceflight composite stress induces depressive behaviors in model rats through disrupting hippocampus synaptic plasticity
2024
Introduction Long‐term spaceflight composite stress (LSCS) can cause adverse effects on human systems, including the central nervous system, which could trigger anxiety and depression. Aims This study aimed to identify changes in hippocampus synaptic plasticity under LSCS. Methods The present study simulated the real long‐term space station environment by conducting a 42‐day experiment that involved simulating microgravity, isolation, noise, circadian rhythm disruptions, and low pressure. The mood and behavior of the rats were assessed by behavior test. Transmission electron microscopy and patch‐clamp were used to detect the changes in synapse morphology and electrophysiology, and finally, the expression of NMDA receptor channel proteins was detected by western blotting. Results The results showed that significant weight loss, anxiety, and depressive behaviors in rats were observed after being exposed to LSCS environment for 42 days. The synaptic structure was severely damaged, manifested as an obvious decrease in postsynaptic density thickness and synaptic interface curvature (p < 0.05; p < 0.05, respectively). Meanwhile, LTP was significantly impaired (p < 0.0001), and currents in the NMDAR channel were also significantly reduced (p < 0.0001). Further analysis found that LSCS decreased the expression of two key subtype proteins on this channel. Conclusion These results suggested that LSCS‐induced depressive behaviors by impairing synaptic plasticity in rat hippocampus. LSCS‐induced depressive behaviors by impairing synaptic plasticity in rat hippocampus. The underlying mechanism may be that LSCS lead the failure of NMDAR channels to open normally by reducing the expression of key subtypes NR2A and NR2B, resulting in the dysregulation of intracellular calcium levels so that LTP cannot be triggered normally, and finally lead the impairment of synaptic plasticity.
Journal Article
COVID-19 pandemic related long-term chronic stress on the prevalence of depression and anxiety in the general population
2021
Background
The COVID-19 pandemic has lasted for more than 1 year, causing far-reaching and unprecedented changes in almost all aspects of society. This study aimed to evaluate the long-term consequences of the COVID-19 pandemic on depression and anxiety, and explore the factors associated with it.
Methods
A cross-sectional study using an online survey was conducted to assess mental health problems from February 2 to February 9, 2021 by using patient health questionnaire-9 (PHQ-9) and generalized anxiety disorder-7 (GAD-7). The insomnia severity index (ISI), demographic data and COVID-19 related variables were measured by a self-designed questionnaire. The factors associated with depressive and anxiety symptoms were identified by Pearson chi-square test and binary logistic regression analysis.
Results
In the study that 1171 participants enrolled, the overall prevalence of depressive and anxiety symptoms among general people was 22.6 and 21.4% respectively in the present study. Living alone was a potential risk factor for depressive symptoms, while regular exercises was a potential protective factor. The prevalence of depressive and anxiety symptoms was significantly associated with the severity of insomnia symptoms and the negative feelings about pandemic.
Conclusion
COVID-19 pandemic- related chronic stress has brought about profound impacts on long-term mental health in the general population. The level of insomnia and a negative attitude towards the pandemic are significantly correlated with unfavorable mental health. However, we failed to found a significant association of age and gender with the mental health symptoms, although they were recognized as well-established risk factors during the outbreak by some other studies. This discrepancy may be because the acute and chronic effects of the pandemic are influenced by different factors, which reminds that more attention should be paid to the intrinsic psychological factors and physical reactions towards COVID-19.
Journal Article
Effect of arsenic stress on 5-methylcytosine, photosynthetic parameters and nutrient content in arsenic hyperaccumulator Pteris cretica (L.) var. Albo-lineata
by
Zemanová, Veronika
,
Pavlíková, Daniela
,
Kotrba, Pavel
in
5-methylcytosine
,
5-Methylcytosine - metabolism
,
Accumulation
2020
Background
Arsenic toxicity induces a range of metabolic responses in plants, including DNA methylation. The focus of this paper was on the relationship between As-induced stress and plant senescence in the hyperaccumulator
Pteris cretica
var. Albo-lineata (
Pc
-Al). We assume difference in physiological parameters and level of DNA methylation in young and old fronds as symptoms of As toxicity.
Results
The As accumulation of
Pc
-Al fronds, grown in pots of haplic chernozem contaminated with 100 mg As kg
− 1
for 122 days, decreased with age. Content of As was higher in young than old fronds for variants with 100 mg As kg
− 1
(2800 and 2000 mg As kg
− 1
dry matter, respectively). The highest As content was determined in old fronds of
Pc
-Al grown in pots with 250 mg As kg
− 1
. The increase with age was confirmed for determined nutrients – Cu, Mg, Mn, S and Zn. A significant elevation of all analysed nutrients was showed in old fronds. Arsenic accumulation affected DNA methylation status in fronds, but content of 5-methylcytosine (5mC) decreased only in old fronds of
Pc
-Al (from 25 to 12%). Determined photosynthetic processes showed a decrease of fluorescence, photosynthetic rate and chlorophylls of As treatments in young and old fronds. Water potential was decreased by As in both fronds. Thinning of the sclerenchymatous inner cortex and a reduction in average tracheid metaxylem in the vascular cylinder was showed in roots of As treatment. Irrespective to fronds age, physiological parameters positively correlated with a 5mC while negatively with direct As toxicity. Opposite results were found for contents of Cu, Mg, Mn, S and Zn.
Conclusions
The results of this paper point to changes in the metabolism of the hyperaccumulator plant
Pc
-Al
,
upon low and high exposure to As contamination. The significant impact of As on DNA methylation was found in old fronds. Irrespective to fronds age, significant correlations were confirmed for 5mC and As toxicity. Our analysis of the very low water potential values and lignification of cell walls in roots showed that transports of assimilated metabolites and water between roots and fronds were reduced. As was showed by our results, epigenetic changes could affect studied parameters of the As hyperaccumulator plant
Pc
-Al, especially in old fronds.
Journal Article
Standardized multimodal intervention for stress-induced exhaustion disorder: an open trial in a clinical setting
2020
Background
Long-term sick-leave due to stress-related ill-health is increasing in several economically developed countries. Even though different forms of interventions are administered in regular care for stress-related disorders, such as Stress-induced Exhaustion disorder (SED), the scientific evidence for the effectiveness of such treatments is sparse. The objective of this study was to explore changes in SED-symptoms and return-to-work-rates in a large group of SED-patients participating in a standardized Multimodal intervention (MMI) in a clinical setting.
Method
This open clinical trial tracked 390 patients who fulfilled the criteria for SED undergoing a 24-week MMI, including return-to-work-strategies. Before inclusion, all patients underwent a multi-professional assessment by a team of licensed physicians, licensed psychologists, and licensed physiotherapists. Self-rated questionnaires were administered before treatment, at treatment-start, mid-treatment, post-treatment, and at 12-month follow-up. Within-group change was evaluated over time with mixed-effects models. Beyond different symptoms, working time, sick-leave compensation, and adverse effects were also measured.
Results
There were significant improvements in symptoms of SED, burnout, anxiety, depression, and insomnia, with large within-group effect sizes (
d =
0.91–1.76), improvements that were maintained at 12-month follow-up. Furthermore, there was a significant increase in quality of life and large improvements in average working time and sick-leave compensation. Some adverse effects were reported, mainly concerning an increase in stress, anxiety, and worry.
Conclusion
SED-patients participating in this standardized MMI reported large symptom alleviation, increased working time and reduced sick-leave compensation, indicating a beneficial treatment. There were some adverse effects, but no more so than other psychological treatments. This study confirms previous findings that high levels of depression and anxiety decrease to sub-clinical levels during treatment, while symptoms of SED also decline, yet still persists above sub-clinical levels at 12-month follow-up. On the whole, this open clinical trial suggests that a standardized MMI, administered in a clinical setting, improves symptoms and return-to-work rates in a clinically representative SED-population.
Trial registration
This study was registered on Clinicaltrials.gov 2017.12.02 (Identifier:
NCT03360136
).
Journal Article
Increased Health and Wellbeing in Preschools (DAGIS) Study—Differences in Children’s Energy Balance-Related Behaviors (EBRBs) and in Long-Term Stress by Parental Educational Level
2018
This paper describes the Increased Health and Wellbeing in Preschools (DAGIS) survey process and socioeconomic status (SES) differences in children’s energy balance-related behaviors (EBRBs), meaning physical activity, sedentary and dietary behaviors, and long-term stress that serve as the basis for the intervention development. A cross-sectional survey was conducted during 2015–2016 in 66 Finnish preschools in eight municipalities involving 864 children (3–6 years old). Parents, preschool personnel, and principals assessed environmental factors at home and preschool with questionnaires. Measurement of children’s EBRBs involved three-day food records, food frequency questionnaires (FFQ), seven-day accelerometer data, and seven-day sedentary behavior diaries. Children’s long-term stress was measured by hair cortisol concentration. Parental educational level (PEL) served as an indicator of SES. Children with low PEL had more screen time, more frequent consumption of sugary beverages and lower consumption of vegetables, fruit, and berries (VFB) than those with high PEL. Children with middle PEL had a higher risk of consuming sugary everyday foods than children with high PEL. No PEL differences were found in children’s physical activity, sedentary time, or long-term stress. The DAGIS intervention, aiming to diminish SES differences in preschool children’s EBRBs, needs to have a special focus on screen time and consumption of sugary foods and beverages, and VFB.
Journal Article
Alexithymia and frontal–amygdala functional connectivity in North Korean refugees
2020
Refugees commonly experience difficulties with emotional processing, such as alexithymia, due to stressful or traumatic experiences. However, the functional connectivity of the amygdala, which is central to emotional processing, has yet to be assessed in refugees. Thus, the present study investigated the resting-state functional connectivity of the amygdala and its association with emotional processing in North Korean (NK) refugees.
This study included 45 NK refugees and 40 native South Koreans (SK). All participants were administered the Toronto Alexithymia Scale (TAS), Beck Depression Inventory (BDI), and Clinician-administered PTSD Scale (CAPS), and differences between NK refugees and native SK in terms of resting-state functional connectivity of the amygdala were assessed. Additionally, the association between the strength of amygdala connectivity and the TAS score was examined.
Resting-state connectivity values from the left amygdala to the bilateral dorsolateral prefrontal cortex (dlPFC) and dorsal anterior cingulate cortex (dACC) were higher in NK refugees than in native SK. Additionally, the strength of connectivity between the left amygdala and right dlPFC was positively associated with TAS score after controlling for the number of traumatic experiences and BDI and CAPS scores.
The present study found that NK refugees exhibited heightened frontal-amygdala connectivity, and that this connectivity was correlated with alexithymia. The present results suggest that increased frontal-amygdala connectivity in refugees may represent frontal down-regulation of the amygdala, which in turn may produce alexithymia.
Journal Article
A decade of rain exclusion in a Mediterranean forest reveals trade-offs of leaf chemical defenses and drought legacy effects
by
Reiter, Ilja, M
,
Fernandez, Catherine
,
Institut de Biosciences et Biotechnologies d'Aix-Marseille (ex-IBEB) (BIAM) ; Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)-Direction de Recherche Fondamentale (CEA) (DRF (CEA)) ; Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)
in
631/158
,
631/158/2165
,
631/158/2454
2024
Increasing aridity in the Mediterranean region will result in longer and recurrent drought. These changes could strongly modify plant defenses, endangering tree survival. We investigate the response of chemical defenses from central and specialized metabolism in Quercus pubescens Willd. to future Mediterranean drought using a long-term drought experiment in natura where trees have been submitted to amplified drought (~ -30% annual precipitation) since April 2012. We focused on leaf metabolites including chlorophylls and carotenoids (central metabolism) and flavonols (specialized metabolism). Measurements were performed in summer from 2016 to 2022. Amplified drought led to higher concentrations of total photosynthetic pigments over the 2016-2022 period. However, it also led to lower AZ/VAZ and flavonol concentrations. Additionally, chemical defenses of Q. pubescens responded to previous precipitation where low precipitation 1 year and/or 2 years preceding sampling was associated to low concentrations of VAZ, flavonol and high neoxanthin concentrations. Our study indicates that the decline of flavonol concentration under long-term drought is counterbalanced by a higher production of several central metabolites. Such results are potentially due to an adjustment in tree metabolism, highlighting the importance of performing long-term experimental studies in natura for assessing drought legacy effects and thus forest adaptation to climate change.
Journal Article
Long-term effects of chlorine stress on the growth and biochemical indices of Cyclina sinensis
by
Ren, Guoliang
,
Yan, Shiyu
,
Chen, Yihua
in
antioxidant performance
,
chlorine
,
Cyclina sinensis
2025
Chlorine in seawater is toxic to bivalves. This study explored the long-term effects of 20 mg/L, 40 mg/L, and 60 mg/L chlorine on the survival rate, growth, immune, and antioxidant performance of the Cyclina sinensis . After 30 days, neither the 20 mg/L nor 40 mg/L treatment group demonstrated any significant disparity compared with the control group. Nevertheless, significant mortality rates were subsequently observed in all treatment groups. The weight, shell length, and monthly growth rate of C. sinensis in the 60 mg/L group were significantly lower than in the control group ( P < 0.05). Residual chlorine also triggered the antioxidant stress response mechanism. After 90 days, a significant increase occurred in both the total antioxidant capacity and activity of superoxide dismutase ( P < 0.05). Chlorine toxicity caused an immune response in the nonspecific immune system of C. sinensis , with alkaline phosphatase and acid phosphatase activities significantly increasing at 30 days and then significantly decreasing ( P < 0.05). Lysozyme activity also showed a continuous decline after 30 days. These results indicated that C. sinensis was unable to adapt to long-term chlorine toxicity stress but was able to resist chlorine toxicity for a short period (30 days) only when the chlorine concentration was <40 mg/L. Long-term chlorine exposure damaged the immune system of C. sinensis , inhibiting growth and increasing clam mortality. Therefore, in areas where chlorine is used as a disinfectant, the residual chlorine concentration should be tested in the water every 30 days to prevent harm to bivalves caused by long-term chlorine toxicity stress.
Journal Article