Prior exposure to a sensorimotor game in virtual reality does not enhance stress reactivity toward the OpenTSST VR.

Compared to the in-person Trier Social Stress Test (TSST), virtual reality (VR) variants reduce resource-intensity and improve standardization but induce stress with smaller effect sizes. However, higher cortisol reactivity is given for more immersive TSST-VRs. Immersivity depends on the VR-system, but perceived immersion may be targeted by exposure to, or interaction with the VR. We investigated whether stress reactivity towards the openly accessible OpenTSST VR can be enhanced by prior exposure to a sensorimotor game completed in VR as mediated by increased immersion. Therefore, N = 58 healthy participants underwent the OpenTSST VR or its inbuilt control condition (placebo TSST-VR, pTSST-VR). Beforehand, participants completed a sensorimotor game either in VR or in real life. Stress was measured by means of self-reports, salivary cortisol concentrations, and salivary alpha-amylase (sAA) activity. Perceived immersion was assessed with the Igroup Presence Questionnaire (IPQ). The TSST-VR-group showed higher subjective stress than the pTSST-VR-group. Even though area under the curve measures indicated significant differences in cortisol levels between TSST-VR and pTSST-VR, this effect was not replicated in omnibus-analyses. Likewise, sAA was not responsive to stress. Our data suggests the OpenTSST VR does not reliably trigger physiological stress reactivity. Likewise, participants playing the VR-game before exposure to the TSST-VR did not show enhanced stress reactivity. Importantly, playing the VR-game did not lead to increased immersion (indicated by the IPQ), either. The key question resulting from our study is which manipulation may be fruitful to obtain a comparable stress response toward the TSST-VR compared to the in-person TSST.

Dietary intake of microplastics impairs digestive performance, induces hepatic dysfunction, and shortens lifespan in the annual fish Nothobranchius guentheri.

Microplastics (MPs) are ubiquitous in aquatic and terrestrial ecosystem, increasingly becoming a serious concern of human health. Many studies have explored the biological effects of MPs on animal and plant life in recent years. However, information regarding the effects of MPs on aging and lifespan is completely lacking in vertebrate species to date. Here we first confirm the bioavailability of MPs by oral delivery in the annual fish N. guentheri. We then show for the first time that administration of MPs not only shortens the lifespan but also accelerates the development of age-related biomarkers in N. guentheri. We also demonstrate that administration of MPs induces oxidative stress, suppresses antioxidant enzymes, reduces digestive enzymes, and causes hepatic dysfunction. Therefore, we propose that administration of MPs reduces lifespan of N. guentheri via induction of both suppressed antioxidant system and digestive disturbance as well as hepatic damage. Our results also suggest that smaller MPs appear more toxic to digestion, metabolism and growth of animals.

Inducing and Recording Acute Stress Responses on a Large Scale With the Digital Stress Test (DST): Development and Evaluation Study.

BACKGROUND: Valuable insights into the pathophysiology and consequences of acute psychosocial stress have been gained using standardized stress induction experiments. However, most protocols are limited to laboratory settings, are labor-intensive, and cannot be scaled to larger cohorts or transferred to daily life scenarios. OBJECTIVE: We aimed to provide a scalable digital tool that enables the standardized induction and recording of acute stress responses in outside-the-laboratory settings without any experimenter contact. METHODS: On the basis of well-described stress protocols, we developed the Digital Stress Test (DST) and evaluated its feasibility and stress induction potential in a large web-based study. A total of 284 participants completed either the DST (n=103; 52/103, 50.5% women; mean age 31.34, SD 9.48 years) or an adapted control version (n=181; 96/181, 53% women; mean age 31.51, SD 11.18 years) with their smartphones via a web application. We compared their affective responses using the international Positive and Negative Affect Schedule Short Form before and after stress induction. In addition, we assessed the participants' stress-related feelings indicated in visual analogue scales before, during, and after the procedure, and further analyzed the implemented stress-inducing elements. Finally, we compared the DST participants' stress reactivity with the results obtained in a classic stress test paradigm using data previously collected in 4 independent Trier Social Stress Test studies including 122 participants overall. RESULTS: Participants in the DST manifested significantly higher perceived stress indexes than the Control-DST participants at all measurements after the baseline (P<.001). Furthermore, the effect size of the increase in DST participants' negative affect (d=0.427) lay within the range of effect sizes for the increase in negative affect in the previously conducted Trier Social Stress Test experiments (0.281-1.015). CONCLUSIONS: We present evidence that a digital stress paradigm administered by smartphone can be used for standardized stress induction and multimodal data collection on a large scale. Further development of the DST prototype and a subsequent validation study including physiological markers are outlined.

Effects of stress on chewing and food intake in patients with anorexia nervosa.

OBJECTIVE: The present study investigates the impact of psychosocial stress on chewing and eating behavior in patients with anorexia nervosa (PAN ). METHOD: The eating and chewing behavior of PAN were examined in a standardized setting by means of a chewing sensor. These procedures encompassed n = 19 PAN , age, and gender matched to n = 19 healthy controls (HC). Food intake and chewing frequency were assessed in two experimental conditions: rest versus stress (via Trier Social Stress Test). To verify stress induction, two appraisal scales were employed. In addition, chronic stress, psychological distress and eating disorder symptoms were assessed. RESULTS: In terms of food intake and chewing frequency, the results of the 2x2 ANOVA demonstrated a significant effect of condition and group. During stress, all participants demonstrated a higher chewing frequency and a decreased ingestion. In general, patients ate less at a lower chewing frequency (vs. HC). However, sample specific analyses demonstrated that the eating and chewing behavior of PAN remained unchanged regardless of the condition, except for their drinking. Food choices were comparable between the groups, but appetite values significantly differed. DISCUSSION: The increase in chewing frequency in all participants during stress suggests that chewing might impact affect regulation, however, not specifically in PAN . Future research should clarify to what extent the normalization of chewing behavior could ameliorate ED-symptoms (incl. food intake) in PAN . The application of a chewing sensor could support this aim and future interventions.

Physiological and subjective validation of a novel stress procedure: The Simple Singing Stress Procedure.

Laboratory stress-induction procedures have been critical in illuminating the effects of stress on human health, cognition, and functioning. Here, we present a novel stress induction procedure, the Simple Singing Stress Procedure (SSSP), that overcomes some of the practical challenges and conceptual limitations of existing procedures in measuring the causal influence of stress on psychological variables. In the stress condition of the SSSP, participants were instructed to sing a song in front of the experimenter while being video- and audio-recorded. Participants were also informed that they would have to sing again at the end of the experiment, and that this second performance would later be assessed by a panel of experimenters. Participants in a no-stress condition instead read lyrics in each phase. Our findings revealed that participants in the stress condition showed significantly higher blood pressure immediately following the initial singing session, as well as heightened salivary cortisol at a latency consistent with the initial singing session, than those in the no-stress condition. Our stress procedure also generated elevations in self-reported stress ratings immediately after the first singing session and subsequently in anticipation of the second singing session, relative to the no-stress condition. Collectively, these findings suggest that the SSSP is a simple and effective stress induction procedure that may be a promising alternative to existing protocols.

Combined Targeting of Mutant p53 and Jumonji Family Histone Demethylase Augments Therapeutic Efficacy of Radiation in H3K27M DIPG.

Diffuse intrinsic pontine glioma (DIPG) is an aggressive pediatric brainstem tumor with a 5-year survival of <1%. Up to 80% of the DIPG tumors contain a specific K27M mutation in one of the two genes encoding histone H3 (H3K27M). Furthermore, p53 mutations found in >70-80% of H3K27M DIPG, and mutant p53 status is associated with a decreased response to radiation treatment and worse overall prognosis. Recent evidence indicates that H3K27M mutation disrupts tri-methylation at H3K27 leading to aberrant gene expression. Jumonji family histone demethylases collaborates with H3K27 mutation in DIPG by erasing H3K27 trimethylation and thus contributing to derepression of genes involved in tumorigenesis. Since the first line of treatment for pediatric DIPG is fractionated radiation, we investigated the effects of Jumonji demethylase inhibition with GSK-J4, and mutant p53 targeting/oxidative stress induction with APR-246, on radio-sensitization of human H3K27M DIPG cells. Both APR-246 and GSK-J4 displayed growth inhibitory effects as single agents in H3K27M DIPG cells. Furthermore, both of these agents elicited mild radiosensitizing effects in human DIPG cells (sensitizer enhancement ratios (SERs) of 1.12 and 1.35, respectively; p < 0.05). Strikingly, a combination of APR-246 and GSK-J4 displayed a significant enhancement of radiosensitization, with SER of 1.50 (p < 0.05) at sub-micro-molar concentrations of the drugs (0.5 µM). The molecular mechanism of the observed radiosensitization appears to involve DNA damage repair deficiency triggered by APR-246/GSK-J4, leading to the induction of apoptotic cell death. Thus, a therapeutic approach of combined targeting of mutant p53, oxidative stress induction, and Jumonji demethylase inhibition with radiation in DIPG warrants further investigation.

Weight status moderates stress-eating in the absence of hunger associations in children.

OBJECTIVE: The association between stress and eating remains unclear in children potentially due to factors that may moderate the association. We examined whether weight status or sex moderated associations between response to a stress induction and eating in the absence of hunger (EAH), among low-income children. METHOD: Children (n = 223; M age = 7.8 years, SD = 0.7 years) participated in a stress induction protocol (modified Trier Social Stress Test for Children [TSST-C]) during which behavioral coding of observed anxiety and change in self-reported distress were measured. Afterwards, participants completed a standardized EAH protocol where they were offered palatable foods. Total kilocalories consumed during the EAH protocol was calculated. Weight and height were measured and weight status calculated as overweight (BMI ≥ 85th percentile for age and sex) vs. not overweight. Multivariate linear regression models adjusting for covariates were conducted to test whether child weight status or sex moderated the stress response-EAH association, for both stress response variables. RESULTS: Weight status moderated the association between observed stress response and EAH such that children with overweight engaged in more EAH as observed anxiety increased, whereas children without overweight engaged in less EAH as observed anxiety increased (ßinteraction = 0.48; p = .010). Weight status did not moderate associations between self-reported distress and EAH. Child sex was not a significant moderator. CONCLUSIONS: After exposure to stress, children with overweight in middle childhood may eat more palatable food compared to children without overweight, possibly due to hypersensitization to food cues or weight stigma experienced by youth with overweight. It may be helpful to encourage youth with overweight to engage in stress-management techniques that do not involve eating as a response to stress.

Influence of Zn(II) stress-induction on component variation and sorption performance of extracellular polymeric substances (EPS) from Bacillus vallismortis.

Bacillus vallismortis (B. vallismortis), an aerobic heterotrophic bacteria, was screened in a laboratory pilot study, to assess the interaction between the heavy metal Zn(II) and extracellular polymeric substances (EPS). The influence of Zn(II) stress on EPS production, component variation, and sorption performance, was investigated. The characteristics of B. vallismortis EPS formed under stress were analyzed using FTIR, 3D-EEM and XPS. EPS was used as an adsorbent and the adsorption capacity and adsorption behavior of EPS formed with and without Zn(II) stress, were compared and assessed. Results showed that the production of polysaccharides and proteins, the main components of EPS, were promoted under Zn(II) stress. The types of EPS functional groups observed remained the same with and without heavy metal stress, but their concentrations were increased. Due to stress-induction, the adsorption capacity of Zn-EPS was significantly enhanced compared with the control-EPS. Specific EPS produced by B. vallismortis in the presence of Zn(II) stress, could have a wide range of potential applications, allowing optimization and improvement of the capacity of EPS to remove heavy metals from effluent.

Sex and stress: Men and women show different cortisol responses to psychological stress induced by the Trier social stress test and the Iowa singing social stress test.

Acute psychological stress affects each of us in our daily lives and is increasingly a topic of discussion for its role in mental illness, aging, cognition, and overall health. A better understanding of how such stress affects the body and mind could contribute to the development of more effective clinical interventions and prevention practices. Over the past 3 decades, the Trier Social Stress Test (TSST) has been widely used to induce acute stress in a laboratory setting based on the principles of social evaluative threat, namely, a judged speech-making task. A comparable alternative task may expand options for examining acute stress in a controlled laboratory setting. This study uses a within-subjects design to examine healthy adult participants' (n = 20 men, n = 20 women) subjective stress and salivary cortisol responses to the standard TSST (involving public speaking and math) and the newly created Iowa Singing Social Stress Test (I-SSST). The I-SSST is similar to the TSST but with a new twist: public singing. Results indicated that men and women reported similarly high levels of subjective stress in response to both tasks. However, men and women demonstrated different cortisol responses; men showed a robust response to both tasks, and women displayed a lesser response. These findings are in line with previous literature and further underscore the importance of examining possible sex differences throughout various phases of research, including design, analysis, and interpretation of results. Furthermore, this nascent examination of the I-SSST suggests a possible alternative for inducing stress in the laboratory. © 2016 Wiley Periodicals, Inc.

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

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

An experimental laboratory-based minority stress paradigm for alcohol research among sexual minority women: A pilot study.

BACKGROUND: Sexual minority women (SMW) use alcohol at higher rates and experience greater alcohol-related harms than their heterosexual counterparts. Evidence from observational studies suggests that minority stress (i.e., stress experienced due to marginalization in society) is an important risk factor among SMW, yet there is a lack of experimental evidence to establish a direct causal role of minority stress on alcohol use in this population. We adapted the preexisting personalized guided stress induction paradigm to conduct a pilot study of how minority stress is related to stress response (assessed via subjective measures and salivary cortisol) and mechanisms of alcohol use (craving, demand, and risky decision making) in SMW. METHODS: Using a within-subjects design (N = 8) cisgender SMW who endorsed high-risk drinking (≥1 heavy drinking episode in the past 30 days) completed three study visits: a script development session and two in-person imagery induction appointments (minority stress and neutral). Analyses examined feasibility and acceptability, stress response, and mechanisms of alcohol use. RESULTS: The paradigm significantly increased subjective stress response (g = 1.32). Data supported the feasibility, acceptability, and appropriateness of the paradigm for use with SMW. While the paradigm did not significantly change scores on minority stress and alcohol outcomes measures, effect sizes for craving and minority stress outcomes were in the small-to-medium range (gs = 0.24-0.54). CONCLUSIONS: The adapted minority stress paradigm appears to be feasible and appropriate for use with SMW to induce stress in laboratory settings. Future research can use this paradigm to understand the causal effects of minority stress on alcohol use and related outcomes.

Assessing cytotoxicity and endoplasmic reticulum stress in human blood-brain barrier cells due to silver and copper oxide nanoparticles.

In recent years, it has been generally accepted that metal-based nanoparticles (NPs) may induce stress in the endoplasmic reticulum (ER), a key organelle where protein folding occurs. We examined ER stress in immortalized human cerebral microvascular cells (hCMEC/D3) after exposure to silver-NPs (Ag-NPs)- and copper oxide-NPs (CuO-NPs) induced toxicity at < 10 nm and < 40 nm or < 50 nm diameters, respectively. In cytotoxicity assessments, cells were exposed to different CuO-NPs (5-400 µg/mL) or Ag-NPs (1-10 µg/mL) concentration ranges for 24 h and 72 h, and tetrazole salt reduction assays (EZ4U) were performed. Also, Ag-NP or CuO-NP effects on cell proliferation, apoptosis (caspase 3/7 assays), and ER stress and cell morphology were evaluated. In ER stress assessments, RNA-like endoplasmic reticulum kinase (PERK), activating transcription factor 6 (ATF6), inositol-requiring enzyme 1 (IRE1a), and others stress factor mRNA levels were determined after 24 h treatment using Real-Time PCR. Increased stress sensors (IRE1a, PERK, and ATF6) mRNA levels were observed after exposure to Ag-NPs (< 10 and < 40 nm) or CuO-NPs (< 50 nm). We investigated the expression of tight junction (TJ) proteins (barrier junctions) and showed that both types of NP reduced of OCLN gene expression. Morphological changes were observed after Ag-NP or CuO-NP exposure using holotomographic microscopy. Our data suggest that Ag- and CuO-NPs should undergo future in vitro and in vivo toxicology studies, especially for downstream biomedical application and occupational risk assessments.

Exploring biosynthesis strategies to boost the yield of exopolysaccharide-protein blend from Bacillus arachidis SY8(T), an isolated native strain, as a potent adsorbent for heavy metals removal.

This investigation centers on the synthesis of a polysaccharide-protein blend produced by an isolated native strain (99.12 % phylogenetic affinity with Bacillus arachidis SY8(T)). The primary objective was to investigate the production of extracellular polymeric substances (EPS) under diverse stress conditions, encompassing exposure to heavy metal ions, salt, and toxic agents. Additionally, the impact of environmental parameters, namely pH, inoculation percentage, and time, on the production was investigated. Subsequently, the study examined the biosorption potential of the EPS produced for Pb(II), Cu(II), and Mn(II). The EPS obtained was thoroughly characterized via various tests. Rheological evaluations of an EPS solution (2 wt%) confirmed its pseudo-plastic and non-Newtonian fluid properties, while TGA analysis demonstrated its thermal stability up to 600 °C. Additional analyses, including GPC, FTIR, and H-NMR, provide further insights into the produced EPS. The best conditions for EPS production are determined: 5 % NaCl salt, serving as an effective stress inducer, and 37 °C, pH 6, with a 5 % inoculation, over 96 h. EPS demonstrates remarkable removal efficiencies of 99.9, 99.4 and 78.9 % for Pb(II), Cu(II), and Mn(II), respectively. These findings highlight the potential of EPS as an effective agent for removing heavy metal ions.

Discovery of novel peptide-dehydroepiandrosterone hybrids inducing endoplasmic reticulum stress with effective in vitro and in vivo anti-melanoma activities.

Steroid hybrids have emerged as a type of advantageous compound as they could offer improved pharmacological and pharmaceutical properties. Here, we report a series of novel peptide-dehydroepiandrosterone hybrids, which would effectively induce endoplasmic reticulum stress (ERS) and lead to apoptosis with outstanding in vitro and in vivo anti-melanoma effects. The lead compound IId among various steroids conjugated with peptides and pyridines showed effective in vivo activity in B16 xenograft mice: in medium- and high-dose treatment groups (60 and 80 mg/kg), compound IId would significantly inhibit the growth of tumours by 98%-99% compared to the control group, with the highest survival rate as well. Further mechanism studies showed that compound IId would damage the endoplasmic reticulum and upregulate the ERS markers C/EBP homologous protein (CHOP) and glucose-regulated protein 78 (GRP78), which could further regulate caspase and Bcl-2 family proteins and lead to cell apoptosis. The compound IId was also proven to be effective in inhibiting B16 cell migration and invasion.

The Effectiveness of a Mindfulness Induction as a Buffer Against Stress Among University Students With and Without a History of Self-Injury.

Stressful experiences are abundant in university and students with a history of nonsuicidal self-injury (NSSI) may be hyper-reactive to stress. While brief mindfulness inductions have been proposed as a buffer against acute stress, whether they function differently in students with a history of NSSI remains in question. This study sought to explore the impact of an online mindfulness induction on (a) two facets of state mindfulness (i.e., mind and body) and (b) state stress, following a stress induction task, in university students with versus without a history of NSSI. Participants were Canadian university students with (n = 82; Mage = 21.30 years, SD = 2.92; 87.8% female) and without (n = 82; Mage = 21.71 years, SD = 3.18; 87.8% female) a history of NSSI, matched on gender, age, and faculty, who completed baseline (T1) measures of state stress and state mindfulness. Participants were randomly assigned to complete a mindfulness induction or an active control task. All participants then underwent a stress induction, and again completed measures of state stress and state mindfulness (T2). Results from three-way mixed ANOVAs revealed that state stress increased from T1 to T2 for all participants, regardless of group or condition. Among those assigned to the control condition, state mindfulness of the body was lower at T2 for participants with a history of NSSI compared to those without such a history. However, participants with a history of NSSI who completed the mindfulness induction reported greater state mindfulness of the body at T2 than students with a history of NSSI who completed an active control task. Findings highlight the unique response of university students with a history of NSSI to a brief mindfulness induction. Implications are discussed in the context of future research and clinical applications.

Impact of a brief distress intolerance intervention on acute stress modulation of response inhibition neurophysiology in cannabis use disorder.

BACKGROUND: The prevalence of cannabis use in the US has increased within the past two decades. Moreover, cannabis use disorder (CUD) is associated with significant disability, but the underlying neural mechanisms of CUD are unclear. Distress intolerance (DI), a psychological risk factor for CUD, may confer risk in part via impaired inhibitory control (IC) capacity during acute stress. DI and cannabis use problems have been associated with altered N2 amplitude, an IC-related event-related potential, in prior cross-sectional studies, but whether altered N2 is a state marker of CUD severity, a pathoplastic factor responsive to intervention and predictive of CUD symptom change over time, or an enduring trait-like vulnerability is unclear. In this secondary analysis, we tested the impact of a DI-targeted intervention on acute stress-related modulation of the N2 and whether pre-intervention N2 predicted CUD symptom change through follow-up. METHOD: Sixty participants were randomly assigned to a DI-targeted or control intervention. Participants completed an IC task before and after a stress induction at pre- and post-intervention lab visits while EEG activity was recorded. RESULTS: The DI intervention did not alter the N2 compared to a control intervention. Pre-intervention post-stress IC-related N2 was associated with worse CUD severity but did not predict changeover time. CONCLUSION: Findings are consistent with blunted N2 after acute stress acting as a stable marker of CUD severity rather than a pathoplastic factor predictive of CUD trajectory. Future research should investigate whether stress-related blunting of N2 is a consequence of severe CUD or a pre-existing vulnerability.

Developing a stress induction tool relevant to relationships in a health context.

Concerns pertaining to health and to problems in close relationships are both known to be major stressors, yet existing tools are inadequate to assess individual reactions to such stressors. Thus, we sought to develop and preliminarily validate a stress-inducing task for use in a laboratory setting that pertains to the sorts of health-related concerns people face in close relationships. Heterosexual dating couples (44 individuals: mean age 22) were randomized to be paired with their own partner or a stranger and to play a role of speaker or listener. Participants were asked to imagine a scenario in which one person is hit by a car (listener role) and the partner has no means to provide or seek out help for the victim (speaker role). The session consisted of baseline, speech preparation, stress task, and recovery phases. General linear modeling results revealed that the task induced stress, evidenced in cardiovascular activities and self-reported negative affect. Giving a brief speech about the stressful situation creates physiological and psychological strains, regardless of pairing with one's own partner or stranger. Furthermore, cardiovascular and negative affect reactivity to the STress Induction Tool for Close relationships and Health (STITCH) task tended to vary by individual characteristics that reflect one's sensitivity to close relationship-and health-related stress. This tool is intended to be used for testing relationship theory-driven phenomenon and longer-term implications of physiological and affective reactivities in the quality of life and health outcomes of those who experienced a medically stressful circumstance personally or in the family.

ForDigitStress: presentation and evaluation of a new laboratory stressor using a digital job interview-scenario.

Introduction: Since the COVID-19 pandemic, working environments and private lives have changed dramatically. Digital technologies and media have become more and more important and have found their way into nearly all private and work environments. Communication situations have been largely relocated to virtual spaces. One of these scenarios is digital job interviews. Job interviews are usually-also in the non-digital world-perceived as stressful and associated with biological stress responses. We here present and evaluate a newly developed laboratory stressor that is based on a digital job interview-scenario. Methods: N = 45 healthy people participated in the study (64.4% female; mean age: 23.2 ± 3.6 years; mean body mass index = 22.8 ± 4.0 kg/m2). Salivary alpha-amylase (sAA) and cortisol were assessed as measures for biological stress responses. Furthermore, perceived stress was rated at the time points of the saliva samplings. The job interviews lasted between 20 and 25 min. All materials, including instructions for the experimenter (i.e., the job interviewer) and the data set used for statistical analysis, as well as a multimodal data set, which includes further measures, are publicly available. Results: Typical subjective and biological stress-response patterns were found, with peak sAA and perceived stress levels observed immediately after the job interviews and peak cortisol concentrations 5 min afterwards. Female participants experienced the scenario as more stressful than male participants. Cortisol peaks were higher for participants who experienced the situation as a threat in comparison to participants who experienced it as a challenge. Associations between the strength of the stress response with further person characteristics and psychological variables such as BMI, age, coping styles, and personality were not found. Discussion: Overall, our method is well-suited to induce biological and perceived stress, mostly independent of person characteristics and psychological variables. The setting is naturalistic and easily implementable in standardized laboratory settings.

Assessing oxidative stress induction ability and oxidative potential of PM2.5 in cities in eastern and western Japan.

Oxidative stress is an important cause of respiratory diseases associated with exposure to PM2.5. Accordingly, acellular methods for assessing the oxidative potential (OP) of PM2.5 have been evaluated extensively for use as indicators of oxidative stress in living organisms. However, OP-based assessments only reflect the physicochemical properties of particles and do not consider particle-cell interactions. Therefore, to determine the potency of OP under various PM2.5 scenarios, oxidative stress induction ability (OSIA) assessments were performed using a cell-based method, the heme oxygenase-1 (HO-1) assay, and the findings were compared with OP measurements obtained using an acellular method, the dithiothreitol assay. For these assays, PM2.5 filter samples were collected in two cities in Japan. To quantitatively determine the relative contribution of the quantity of metals and subtypes of organic aerosols (OA) in PM2.5 to the OSIA and the OP, online measurements and offline chemical analysis were also performed. The findings showed a positive relationship between the OSIA and OP for water-extracted samples, confirming that the OP is generally well suited for use as an indicator of the OSIA. However, the correspondence between the two assays differed for samples with a high water-soluble (WS)-Pb content, which had a higher OSIA than would be expected from the OP of other samples. The results of reagent-solution experiments showed that the WS-Pb induced the OSIA, but not the OP, in 15-min reactions, suggesting a reason for the inconsistent relationship between the two assays across samples. Multiple linear regression analyses and reagent-solution experiments showed that WS transition metals and biomass burning OA accounted for approximately 30-40% and 50% of the total OSIA or the total OP of water-extracted PM2.5 samples, respectively. This is the first study to evaluate the association between cellular oxidative stress assessed by the HO-1 assay and the different subtypes of OA.

[Measurement of stress response in laboratory settings - a review of studies using stress induction protocols]. / Pomiar reakcji stresowej w warunkach laboratoryjnych ­ przeglad badan wykorzystujacych protokoly wzbudzania stresu.

Stress is one of the main reasons for deterioration in mental and physical health, and it leads to a decrease in work efficiency. Providing appropriate methods of diagnosing the level of stress allows for making a reliable verification of the effectiveness of stress reduction interventions and for assessing individual differences in reactivity to stress. The aim of this study was to review the available studies that use the most common stress induction protocols in laboratory settings and measure psychophysiological reactions to stress. The review included research using the following protocols: MIST, MA, TSST, Stroop Test and PASAT, and measuring brain activity, heart activity, cortisol levels and muscle tones. The analyzes included papers available in the PubMed database, published in 2015‒2021, in which studies were conducted on healthy adults. The analysis of the available studies revealed that the protocols induced changes in the activity of the autonomic nervous system, the cardiovascular system and brain activity. Moreover, TSST is a protocol that is most often used to assess the level of stress and differences in reactivity to induced stress depending on individual differences in personality traits, and to make the comparison of specific groups of people. Measurements of induced stress are usually done by analyzing the cortisol levels in response to stress and changes in heart activity. The MIST test is a commonly used method in neuroimaging studies. The analysis of the research results has revealed that the protocols, beside inducing a typical physiological response, are associated with blunting the physiological response to stress in some people. Med Pr. 2022;73(3):251-70.