Stress In Healthy Individuals Research Articles

Oxidative Stress Reaction to Hypobaric-Hyperoxic Civilian Flight Conditions.

In military flight operations, during flights, fighter pilots constantly work under hyperoxic breathing conditions with supplemental oxygen in varying hypobaric environments. These conditions are suspected to cause oxidative stress to neuronal organ tissues. For civilian flight operations, the Federal Aviation Administration (FAA) also recommends supplemental oxygen for flying under hypobaric conditions equivalent to higher than 3048 m altitude, and has made it mandatory for conditions equivalent to more than 3657 m altitude. We hypothesized that hypobaric-hyperoxic civilian commercial and private flight conditions with supplemental oxygen in a flight simulation in a hypobaric chamber at 2500 m and 4500 m equivalent altitude would cause significant oxidative stress in healthy individuals. Twelve healthy, COVID-19-vaccinated (third portion of vaccination 15 months before study onset) subjects (six male, six female, mean age 35.7 years) from a larger cohort were selected to perform a 3 h flight simulation in a hypobaric chamber with increasing supplemental oxygen levels (35%, 50%, 60%, and 100% fraction of inspired oxygen, FiO2, via venturi valve-equipped face mask), switching back and forth between simulated altitudes of 2500 m and 4500 m. Arterial blood pressure and oxygen saturation were constantly measured via radial catheter and blood samples for blood gases taken from the catheter at each altitude and oxygen level. Additional blood samples from the arterial catheter at baseline and 60% oxygen at both altitudes were centrifuged inside the chamber and the serum was frozen instantly at -21 °C for later analysis of the oxidative stress markers malondialdehyde low-density lipoprotein (M-LDL) and glutathione-peroxidase 1 (GPX1) via the ELISA test. Eleven subjects finished the study without adverse events. Whereas the partial pressure of oxygen (PO2) levels increased in the mean with increasing oxygen levels from baseline 96.2 mm mercury (mmHg) to 160.9 mmHg at 2500 m altitude and 60% FiO2 and 113.2 mmHg at 4500 m altitude and 60% FiO2, there was no significant increase in both oxidative markers from baseline to 60% FiO2 at these simulated altitudes. Some individuals had a slight increase, whereas some showed no increase at all or even a slight decrease. A moderate correlation (Pearson correlation coefficient 0.55) existed between subject age and glutathione peroxidase levels at 60% FiO2 at 4500 m altitude. Supplemental oxygen of 60% FiO2 in a flight simulation, compared to flying in cabin pressure levels equivalent to 2500 m-4500 m altitude, does not lead to a significant increase or decrease in the oxidative stress markers M-LDL and GPX1 in the serum of arterial blood.

Aerobic Exercise and Endocannabinoids: A Narrative Review of Stress Regulation and Brain Reward Systems.

Aerobic exercise is a widely adopted practice, not solely for enhancing fitness and reducing the risk of various diseases but also for its ability to uplift mood and aid in addressing depression and anxiety disorders. Within the scope of this narrative review, we seek to consolidate current insights into the endocannabinoid-mediated regulation of stress and the brain's reward mechanism resulting from engaging in aerobic exercise. A comprehensive search was conducted across Medline, SPORTDiscus, Pubmed, and Scopus, encompassing data available until November 30, 2023. This review indicates that a bout of aerobic exercise, particularly of moderate intensity, markedly augments circulating levels of endocannabinoids-N-arachidonoyl-ethanolamine (AEA) and 2-acylglycerol (2-AG), that significantly contributes to mood elevation and reducing stress in healthy individuals. The current understanding of how aerobic exercise impacts mental health and mood improvement is still unclear. Moderate and high-intensity aerobic exercise modulatesstress through a negative feedback mechanism targeting both the hypothalamus-pituitary-adrenal (HPA) axis and the sympathetic nervous system, thereby facilitating stress regulation crucial role in endocannabinoid synthesis, ultimately culminating in the orchestration of negative feedback across multiple tiers of the HPA axis, coupled with its influence over cortical and subcortical brain structures. The endocannabinoid has been observed to govern the release of neurotransmitters from diverse neuronal populations, implying a universal mechanism that fine-tunes neuronal activity and consequently modulates both emotional and stress-related responses. Endocannabinoids further assume a pivotal function within brain reward mechanisms, primarily mediated by CB1 receptors distributed across diverse cerebral centers. Notably, these endocannabinoids partake in natural reward processes, as exemplified in aerobic exercise, by synergizing with the dopaminergic reward system. The genesis of this reward pathway can be traced to the ventral tegmental area, with dopamine neurons predominantly projecting to the nucleus accumbens, thereby inciting dopamine release in response to rewarding stimuli.

Evaluation of daily Laurus nobilis tea consumption on anxiety and stress biomarkers in healthy volunteers.

Laurus nobilis is known in the field of herbal medicine and in vitro studies for its antibacterial, antifungal, anti- diabetes, and anti-inflammatory beneficial effects. Laurus nobilis tea consumption was investigated with regard to its effects on anxiety and stress in healthy individuals, measured by subjective tools and by plasmatic cortisol levels. The study included thirty healthy Tunisian volunteers aged between 20 and 57 years consuming Laurus nobilis infusion, prepared from 5g of dried Laurus nobilis leaves in 100 ml boiled water, once a day during 10 days. Plasma concentrations of serum cortisol were measured before Laurus nobilis consumption and at the end of the experiment. Laurus nobilis tea consumption significantly decreased the concentration of plasmatic cortisol ([cortisol] D0= 93.5± 43.01ng/mL, D11=72.23± 25.37, p=0.001). A statistically significant decrease in PSS and STAI scores (p=0.006 and p=0.002 respectively) was also noted.These findings highlight the decrease in blood cortisol levels, which means a possible positive effect on reducing the risk of stress related-diseases in healthy volunteers consuming Laurus nobilis tea. However, more powerful studies with extended treatment periods are required.

A Combination of Magnesium, B Vitamins, Rhodiola, and Green Tea (L-theanine) Alleviates Chronic Stress in Healthy Volunteers: A Randomized, Placebo-Controlled Study

ObjectivesThe effect of a combination of magnesium, vitamin B6, B9, B12, and Teadiola® (rhodiola and green tea/L-theanine extracts) on stress was evaluated in chronically stressed but otherwise healthy subjects. The effects on stress-related quality-of-life (QoL) parameters, like sleep and perception of pain were also explored.MethodsThis single-blinded study (NCT04391452) included adults with stress for ≥1 month and with ≥14 points on Depression Anxiety Stress Scale (DASS)-42 stress questionnaire. Subjects were randomized (1:1) to receive either the dietary supplement combination (n = 49) or placebo (n = 51), once daily, for 28 days, with a follow-up assessment at day 56. Primary endpoint was the change in DASS-42 stress score from baseline (BL) to day 28 in dietary supplement vs placebo groups. Secondary endpoints included changes from BL in DASS-42 scores at days 14 and 56; sleep quality (Pittsburgh Sleep Quality Index [PSQI]) at days 14, 28, and 56; pain perception (temperature threshold) in response to cold/warm thermal stimulations at day 28.ResultsAt BL, DASS-42 score (mean [SD]) was 26.3 (6.7) with dietary supplement and 26.8 (8.0) with placebo. At day 28, the scores decreased to 17.6 (7.3) and 20.1 (9.4), respectively, with a significant between-group difference of 3 points (effect size [ES], −0.29; 95% CI [−0.57, −0.01]; p = 0.04). Similar reductions were observed earlier, at day 14 (ES, −0.40; 95% CI [−0.68, −0.11]; p = 0.006), that remained stable up to day 56 (ES, −0.34; 95% CI [−0.62, −0.06]; p = 0.02). At day 28, a significant reduction in sensitivity to cold pain was reported with dietary supplement vs placebo (p = 0.01) and a trend for lesser sensitivity to hot pain was observed (p = 0.06). No significant effect was observed on overall sleep quality, but a trend towards improvement in daytime dysfunction due to sleepiness (PSQI-7 component score) was noticed with dietary supplement vs placebo at day 28 (p = 0.06) which became significant at day 56 (p < 0.001).ConclusionsThe combination is effective for management of stress in healthy individuals. Its beneficial effects on stress-related QoL aspects, notably pain perception, deserve further investigation.Funding SourcesThis study was sponsored by the University Hospital of Clermont-Ferrand, France and received partial financial support from Sanofi Consumer Healthcare, the manufacturer of Stress Resist®.

Concepções históricas da construção da psiquiatria contemporânea: uma reflexão teórica do cuidado transpandêmico

The aim was to analyze the historical context of ancient and current psychiatry and the repercussions in the pre and transpandemic period. This is a reflection study, with a descriptive and critical-reflexive character, based on Pinel's theory of “Moral Treatment” in the context of the treatment of patients in asylums that are considered alienated. For development, three categories were listed, such as Psychiatry and Pinel: history, Psychiatry in Brazil and COVID-19: mental health and the future of psychiatry. The changes arising from the pandemic context triggered several psychological shocks in the population that complied with the quarantine demand. It can be highlighted the increase in the level of stress, anxiety, depression (the latter increased by 25%, according to the most recent data from the World Health Organization), psychological trauma, anguish linked to grief and other fears related to death and unemployment. When we talk about the pandemic, the fear it brings increases levels of anxiety and stress in healthy individuals and intensifies the symptoms of those with pre-existing psychiatric disorders. Thus, even with the publication of some reports on local health care strategies, more comprehensive emergency guidelines for this pandemic scenario are still not known.

Effect of Box Breathing Technique on Lung Function Test

Background: Box breathing exercise is a technique of slow breathing rhythm also known as square breathing used universally. It increases the performance and concentration level, it also acts as a powerful stress relief. It is tested with a spirometer for the lung function test that measures the airflow of the upper and lower respiratory tract. This method builds up carbon dioxide in blood which calms down and regulates the ANS (Autonomic Nervous System), which enhances the cardio- inhibitory response of the vagus nerve that improves the mood. The main aim of the study was to analyze the effect of box breathing technique on lung function&#x0D; Materials and Methods: The present study was carried out among the participants at the age of 18-25 years from Saveetha Dental College. A total of 30 participants were included in this study (15 males, 15 females). The experimental training procedures consisted of 2 sessions of box breathing day and night for a period of 30 days. Participants were informed of the procedures of the box breathing technique. RMS Helios spirometer was used to measure lung volumes and capacities. Statistics analysis was done using SPSS software, paired t test. P value of less than or equal to 0.05 was considered significant statistically.&#x0D; Results: There was a significant increase among the participants FVC (Forced Vital Capacity), FEV1 (Forced Expiratory Volume), FIVC (Forced Inspiratory Vital Capacity) parameters after 2 sessions on each day of box breathing technique for a period of 30 days. Other parameters increased to 10% but not significantly.&#x0D; Conclusion: The present study illustrates the potential for box breathing practice to improve lung performance and reduce stress in healthy individuals. Despite the significant difference in FVC, FEV, FIVC levels supporting improved lung function, further investigation is needed to delineate mechanisms that underlie these benefits

The effects of neuromodulation priming to Intermittent Theta Burst Transcranial Magnetic Stimulation (iTBS): effects on physiological and subjectives measures of stress in healthy individuals

The effects of neuromodulation priming to Intermittent Theta Burst Transcranial Magnetic Stimulation (iTBS): effects on physiological and subjectives measures of stress in healthy individuals

Oxidative stress in healthy individuals; circadian rhythm of thiol-disulfide balance

Oxidative stress in healthy individuals; circadian rhythm of thiol-disulfide balance

Possible utilization of salivary IFN-γ/IL-4 ratio as a marker of chronic stress in healthy individuals.

IntroductionSeveral studies show that psychological stress reduces Th1/Th2 ratio in blood samples. However, evidence is scarce regarding the cytokine alterations during stress in saliva. We investigated the influence of chronic stress on Th1/Th2 ratio and cytokine profiles in the saliva of healthy individuals. Further, we examined the associations of the salivary cytokine levels with sleep and attention problems, which are closely related with psychological stress.MethodsSalivary levels of 27 cytokines were measured by multiplex bead array assays in 31 healthy young individuals (health science students and hospital staff consisting of 11 men and 20 women, mean age [standard deviation] =21.5 [0.8] years). The Kessler Psychological Distress scale (K10) and Athens Insomnia Scale (AIS) were administered to assess subjective chronic psychological stress and sleep problems. Further, participants were asked to wear Actigraph GT3X accelerometers for 3 days to assess the total sleep time. Attention problems were assessed by administering the Integrated Visual and Auditory Continuous Performance Test (IVA‐CPT).ResultsThirteen cytokines with >80% detectable results were included in the main analyses. The IFN‐γ/IL‐4 ratio, which is a commonly used index for Th1/Th2 ratio, showed significant negative correlations with the K10 and AIS scores. None of the cytokines were significantly associated with sex, body mass index, sleep index measured by Actigraph, or IVA‐CPT scores.ConclusionChronic stress may be associated with alterations of the Th1/Th2 balance in salivary cytokine production. IFN‐γ/IL‐4 ratio in saliva may serve as a potential biomarker of chronic stress in healthy individuals.

Presleep physiological stress is associated with a higher cortical arousal in sleep and more consolidated REM sleep

How sleep regulates physiological stress in healthy individuals is not well understood. We explored the associations between naturally occurring pre-sleep physiological arousal and EEG power spectral density together with rapid eye movement sleep (REMS) continuity. One hundred and fifty-four individuals (mean age 16.9, SD 0.1 years) collected five samples of saliva between the evening (mean time 18:20) and bedtime (mean 23:00) by using swabs, and underwent an overnight in-home polysomnography. We calculated spectral density for REMS and non-rapid eye movement sleep (non-REMS), and the number and duration of REMS arousals (<15 s) during sleep. An observational design allowed for measurement of natural variation in physiological and sleep arousal. Increasing cortisol levels toward bedtime were associated with higher EEG power spectral density at all frequency ranges in frontal locations, the highest association being for the beta1 frequency band. In central locations, the associations were pronounced for beta1 and beta2 bands. Higher overall cortisol levels in the evening were associated with less fragmented REMS. Presleep arousal was not associated with sleep staging. Physiological arousal toward bedtime was associated with EEG power spectral density values during sleep specifically at high EEG frequencies. This may represent a compensatory mechanism that serves as an adaptation to stress, since the REMS was more continuous along a higher physiological arousal level in the evening. Although causality cannot be inferred, a design with nonmanipulated physiological stress followed by naturally timed sleep at home provides new insights into stress regulation homeostasis.

Obsessive-compulsive disorder reinforcement during the COVID-19 pandemic.

The COVID-19 pandemic is unquestionably impacting on the mental health of the population worldwide. Fear of contamination can both increase levels of stress in healthy individuals and intensify psychiatric symptoms in patients with pre-existing conditions, especially obsessive-compulsive disorder (OCD). During the COVID-19 pandemic, the imminent risk of contamination creates a logical need for self-surveillance and hygiene habits. However, this kind of information can have drastic implications for subjects with OCD, since cognitive distortions and compensatory strategies (cleansing rituals) are no longer irrational or oversized – rather, these ideas become legitimate and socially accepted, generating plausible validation for the intensification of compulsive cleaning rituals. Patients who presented remission of OCD symptoms would be more likely to have a relapse, and subclinical patients may scale up and ultimately be diagnosed with OCD due to the reinforcement of their habits, emotions and thoughts.

Dorsal attention network centrality increases during recovery from acute stress exposure

Stress is a major risk factor for the development of almost all psychiatric disorders. In addition to the acute stress response, an efficient recovery in the aftermath of stress is important for optimal resilience. Increased stress vulnerability across psychiatric disorders may therefore be related to altered trajectories during the recovery phase following stress. Such recovery trajectories can be quantified by changes in functional brain networks. This study therefore evaluated longitudinal functional network changes related to stress in healthy individuals (N = 80), individuals at risk for psychiatric disorders (healthy siblings of schizophrenia patients) (N = 39), and euthymic bipolar I disorder (BD) patients (N = 36). Network changes were evaluated before and at 20 and 90 min after onset of an experimental acute stress task (Trier Social Stress Test) or a control condition. Whole-brain functional networks were analyzed using eigenvector centrality as a proxy for network importance, centrality change over time was related to the acute stress response and recovery for each group. In healthy individuals, centrality of the dorsal attention network (DAN; p = 0.007) changed over time in relation to stress. More specifically, DAN centrality increased during the recovery phase after acute stress exposure (p = 0.020), while no DAN centrality change was observed during the initial stress response (p = 0.626). Such increasing DAN centrality during stress recovery was also found in healthy siblings (p = 0.016), but not in BD patients (p = 0.554). This study highlights that temporally complex and precise changes in network configuration are vital to understand the response to and recovery from stress.

S225. STRESS SENSITIZATION IN INDIVIDUALS WITH SUBCLINICAL SYMPTOMS INDICATIVE OF PSYCHOPATHOLOGY

BackgroundRepeated exposure to stressors can sensitize the stress system and in turn propel the development of various psychiatric disorders. Stress sensitization can be identified through stress reactivity patterns. Individuals at risk of developing psychosis for example, already show aberrant patterns of daily stress reactivity prior to clinical diagnosis, with blunted physiological responses to mild stressors that could be indicative of a dysregulation of the hypothalamic pituitary adrenocortical axis. In parallel, while they do not show significant physiological responses to the stressor, they report significant increases in negative affect (NA) ensuing from it. This study aims to test whether sensitization can already be observed in healthy volunteers exhibiting only subclinical symptoms.MethodsThirty, first year students took part in two laboratory sessions where stress was induced using a modified version of the Montreal Imaging Stress Task (MIST), one week apart. Baseline measures of psychopathology were collected using the Symptom Checklist 90 (SCL-90). During the laboratory sessions, continuous ECG signals were collected, as well as five subjective stress measures per session. We calculated average heart rate (HR) and heart rate variability (HRV) per condition. Multilevel models testing the three-way interaction between psychopathology, session, and condition with individual data points nested within days were used to assess overall psychopathology and more specifically subclinical symptoms of psychosis in repeated stress reactivity.ResultsMixed models investigating repeated stress in overall psychopathology indicates a significant three way interaction for HR (β = -.15, SE=.01, p< .01), and HRV (β = -.01, SE=.04, p= .02), with individuals scoring lower on the scl-90 exhibiting comparable increases in HR and decreases in HRV on both sessions. In contrast, individuals scoring higher on the scale show a blunted response on the second session compared to the first. Analyses with stress (β = .03, SE= .01, p= .01), and NA (β = .06, SE=.29, p= .03) show that generally the stressor elicited a mild negative subjective response with a decrease in stress and NA that was comparable on both sessions for individuals scoring lower on the scl-90. No subjective reactivity was reported on the second session for participants scoring high on the scale. Likewise, models that focused on subclinical psychotic symptoms found similar significant interactions. In the same way as in the analyses with psychopathology we find significant interactions for stress (β = .36, SE= .11, p< .01), NA (β = .06, SE=.03, p= .03) HR (β = -1.08, SE=.13 p< .01), and HRV (β = 3.72, SE=.39, p< .01). Analyses show the same comparable patterns of reactivity in both sessions for participants low in psychosis, and a blunted response on the second session for participants high in psychosis.DiscussionSymptoms of psychopathology and more specifically psychosis are related to blunted stress reactivity during a second exposure to the same stressor. Psychopathological vulnerability may be reflected in a blunting response to repeated stress in healthy individuals with subclinical symptoms. Findings suggest that dysregulation in the stress system may be present long before individual complaints, further highlighting the need for early intervention.

Adaptation reactions of hemodynamic systems on artificially modulated stress in healthy individuals

Aim. To study the influence of artificially created stress on hemodynamic parameters of peripheral microcirculation and variability of the heart rhythm in somatically healthy young individuals.&#x0D; Materials and Methods. In the study 30 individuals were involved (of them 16 men) with the mean age 18.21.1 years. An artificial stress was created using Stroop method. Assessment of characteristics of hemodynamics of microcirculation (HM) was performed by the method of dynamic scattering of light from erythrocytes. The signal was integrated in the form of three hemodynamic indexes: HI (Hemodynamic Indexes). Low frequency index (HI1) was determined by a slow interlayer interaction, high frequency area (HI3) characterized fast shearing of layers. HI2 took intermediate position (precapillary and capillary blood flow). Variability of cardiointervals isolated from pulse component, was assessed by method of variation pulsometry (Heart Rate Variability, HRV).&#x0D; Results. In the course of study, increase in the heart rate (HR) in the stage of testing was observed that confirms a high extent of stress load. In hemodynamics, redistribution of blood flow was noted toward slow shear velocities (near-wall blood flow). After cessation of stress load, hemodynamic parameters declined and returned to previous values. Parameters characterizing variability of rhythm LF (sympathetic component), HF (vagal activity), CVI (non-linear parasympathetic index) showed a tendency to growth; here, LF/HF ratio did not change.&#x0D; Conclusion. In result of the carried out study it was possible to formulate a multifactor picture of variation of parameters of microcirculation and of autonomic regulation of cardiac rhythm specific of reactions of adaptation to induced stress. The quantitative criteria of the obtained shears may be integrated into stress indexes to be used in clinical practice. A portable mDLS sensor may be supplemented with specific assessment criteria and used for monitoring of adaptive reactions induced by stressful situations, and for taking early diagnostic and prognostic decisions in the clinical practice, and for self-control of a patient.

Automatically generated smartphone data and subjective stress in healthy individuals – a pilot study

Background: Most people will also experience symptoms of stress at some point. Smartphone use has increased during the last decade and may be a new way of monitoring stress. Thus, it is of interest to investigate whether automatically generated smartphone data reflecting smartphone use is associated with subjective stress in healthy individuals.Aims: to investigate whether automatically generated smartphone data (e.g. the number of outgoing sms/day) was associated with (1) smartphone-based subjectively reported perceived stress, (2) perceived stress (Cohen’s Perceived Stress Scale (PSS)) (3) functioning (Functioning Assessment Short Test (FAST)) and (4) non-clinical depressive symptoms (Hamilton Depression Rating Scale 17-items (HDRS)).Methods: A cohort of 40 healthy blood donors used an app for daily self-assessment of stress for 16 weeks. At baseline participants filled out the PSS and were clinically evaluated using the FAST and the HDRS. The PSS assessment was repeated at the end of the study. Associations were estimated with linear mixed effect regression and linear regression models.Results: There were no statistically significant associations between automatically generated smartphone data and perceived stress, functioning or severity of depressive symptoms, respectively (e.g. the number of outgoing text messages/day and self-assessed stress (B = 0.30, 95% CI: –0.40; 0.99, p = .40).Conclusions: Participants presented with low levels of stress during the study. Automatically generated smartphone data was not able to catch potential subjective stress among healthy individuals in the present study. Due to the small sample and low levels of stress the results should be interpreted with caution.

Reward-Related Striatal Responses Following Stress in Healthy Individuals and Patients With Bipolar Disorder

BackgroundStress has a major impact on the onset and recurrence of mood episodes in bipolar disorder (BD), but the underlying mechanisms remain unknown. Previous studies have shown distinct time-dependent effects of stress on reward processing in healthy individuals. Impaired reward processing is a core characteristic of BD, and altered reward processing during recovery from stress could influence the development and course of bipolar disorder. MethodsWe investigated brain responses during reward processing 50 minutes after stress using functional magnetic resonance imaging in 40 healthy control subjects and 40 patients with euthymic BD assigned to either an acute stress test (Trier Social Stress Test) or a no-stress condition. ResultsAcute stress increased cortisol levels in both healthy control subjects and patients with BD. Ventral striatal responses to reward outcome were increased in healthy control subjects during stress recovery but not in patients with BD. For anticipation, no differences were found between the groups following stress. ConclusionsFor the first time, we show altered reward processing in patients with BD during the recovery phase of stress. These data suggest reduced neural flexibility of hedonic signaling in response to environmental challenges. This may increase the susceptibility to stressful life events in the future and play a role in the development of further psychopathology in the longer term.

Temporal variability in urinary pesticide concentrations in repeated-spot and first-morning-void samples and its association with oxidative stress in healthy individuals

Exposure of humans to pesticides is widespread. Measurement of urinary levels of pesticides and their metabolites is often used in the assessment of body burdens and exposure doses to these chemicals. An understanding of temporal variability in urinary levels of pesticides within individuals is critical for accurate exposure assessment. We examined within- and between-individual variability in concentrations of nine organophosphate and pyrethroid insecticides as well as two phenoxy herbicides in urine collected consecutively for up to 44 days from 19 individuals. Seven oxidative stress biomarkers also were measured in urine samples to elucidate their relationship with pesticide exposure. Intraclass correlation coefficients (ICCs) were calculated to assess reproducibility in urinary pesticide concentrations from repeated measures. Sensitivity and specificity analyses were performed to evaluate the suitability of spot urine to characterize average exposures. Data analysis was further limited to seven pesticides and their metabolites, which had a detection frequency of >60%. Poor reproducibility was found for the seven pesticides and their metabolites in both spot (ICCs ≤0.24) and first-morning-void (FMV) samples (ICCs <0.38) collected during the 44-day study period. Use of single-spot or FMV sample to classify high (top 33%) concentrations showed high specificities (0.73–0.85) but low sensitivities (0.45–0.70). The minimum number of samples (k) required per individual to estimate participant-specific mean value for pesticides (within 20% of the “true” values) were 28–140 and 18–119 for spot and FMV samples, respectively. Repeated longitudinal measurements of these pesticides and their metabolites in urine showed considerable within-individual variability in both spot and FMV samples. Urinary concentrations of seven pesticides and their metabolites were significantly correlated with oxidative damage to lipids, proteins, and DNA.

Preliminary data indicating a connection between stress-induced prefrontal dopamine release and hippocampal TSPO expression in the psychosis spectrum

Prolonged stress can cause neuronal loss in the hippocampus resulting in disinhibition of glutamatergic neurons proposed to enhance dopaminergic firing in subcortical regions including striatal areas. Supporting this, imaging studies show increased striatal dopamine release in response to psychosocial stress in healthy individuals with low childhood maternal care, individuals at clinical high risk for psychosis (CHR) and patients with schizophrenia. The prefrontal cortex (PFC) is connected to the hippocampus and a key region to control neurochemical responses to stressful stimuli. We recently reported a disrupted PFC dopamine-stress regulation in schizophrenia, which was intact in CHR. Given the available evidence on the link between psychosocial stress, PFC dopamine release and hippocampal immune activation in psychosis, we explored, for the first time in vivo, whether stress-induced PFC dopamine release is associated with hippocampal TSPO expression (a neuroimmune marker) in the psychosis spectrum. We used an overlapping sample of antipsychotic-naïve subjects with CHR (n = 6) and antipsychotic-free schizophrenia patients (n = 9) from our previously published studies, measuring PFC dopamine release induced by a psychosocial stress task with [11C]FLB457 positron emission tomography (PET) and TSPO expression with [18F]FEPPA PET. We observed that participants on the psychosis spectrum with lower stress-induced dopamine release in PFC had significantly higher TSPO expression in hippocampus (β = −2.39, SE = 0.96, F(1,11) = 6.17, p = 0.030). Additionally, we report a positive association between stress-induced PFC dopamine release, controlled for hippocampal TSPO expression, and Global Assessment of Functioning. This is the first exploration of the relationship between PFC dopamine release and hippocampal TSPO expression in vivo in humans.

Variability in cerebral blood flow velocity at rest and during mental stress in healthy individuals: Associations with cardiovascular parameters and cognitive performance

This study analyzed variability in cerebral blood flow velocity (CBFV) and possible underlying physiological mechanisms during rest and a mental arithmetic task. Blood flow velocities were bilaterally recorded by transcranial Doppler sonography in the anterior and middle cerebral arteries of 43 participants. Electrocardiography, continuous blood pressure (BP) and respiratory recordings were additionally obtained. Fast Fourier transformation revealed a spectral profile with two main components in CBFV, one in the very low frequency (VLF, 0.01–0.025 Hz), and the other in the low frequency band (LF, 0.075–0.11 Hz). During the task, CBFV variability decreased. While heart rate variability and respiration had only weak impacts, BP variability was closely associated with CBFV variability. LF CBFV variability correlated negatively with task performance. The findings indicate a connection between peripheral and cerebral hemodynamics, presumably mediated by the passive pressure-flow relationship and neural mechanisms. LF CBFV variability may constitute a suitable marker of mental effort load.

Phytochemical Components of Some Minor Cereals Associated with Diabetes Prevention and Management

Diabetes is a metabolic disorder by a chronic hyperglycemic condition because of defects in insulin secretion and insulin action or both. Minor cereals are often drought tolerant and fertilizer efficient. In this review we focus the content and bioavailability of phytochemicals in some minor cereals on the basis evidence for increasing plasma phytochemical concentrations and reducing oxidative stress as well as inflammation in humans. Phenolics and Flavanoids are major phytochemicals and may be available with high concentration in minor cereals but as tightly attached with cell wall, their bioavailability is mostly limited. Clinical trials concluded that vitamin E and other common antioxidants were not helpful for managing diabetic complications. Vicious cycles can cause type 1 DM, where as hypoglycemia can forward to down and regulate neuroendocrine. Increased phytochemical bioavailability may be achieved through bio processing of grains but the improvements might be small and have not yet led to changes in clinical associated with reduced risk of T2D. Furthermore, the effects of minor cereals against oxidative stress in healthy individuals can be very low or not occurred but systemic inflammation can be reduced in people after huge intake. More than 300 Indian medicinal plants have antidiabetic property but exact mechanisms for hypoglycemic action of many plants are still unknown. Further studies are required to pay attention toward direct role of minor cereal phytochemicals on alarming diseases diabetes.