Function In Healthy Individuals Research Articles

Photobiomodulation Therapy on Brain: Pioneering an Innovative Approach to Revolutionize Cognitive Dynamics.

Photobiomodulation (PBM) therapy on the brain employs red to near-infrared (NIR) light to treat various neurological and psychological disorders. The mechanism involves the activation of cytochrome c oxidase in the mitochondrial respiratory chain, thereby enhancing ATP synthesis. Additionally, light absorption by ion channels triggers the release of calcium ions, instigating the activation of transcription factors and subsequent gene expression. This cascade of events not only augments neuronal metabolic capacity but also orchestrates anti-oxidant, anti-inflammatory, and anti-apoptotic responses, fostering neurogenesis and synaptogenesis. It shows promise for treating conditions like dementia, stroke, brain trauma, Parkinson's disease, and depression, even enhancing cognitive functions in healthy individuals and eliciting growing interest within the medical community. However, delivering sufficient light to the brain through transcranial approaches poses a significant challenge due to its limited penetration into tissue, prompting an exploration of alternative delivery methods such as intracranial and intranasal approaches. This comprehensive review aims to explore the mechanisms through which PBM exerts its effects on the brain and provide a summary of notable preclinical investigations and clinical trials conducted on various brain disorders, highlighting PBM's potential as a therapeutic modality capable of effectively impeding disease progression within the organism-a task often elusive with conventional pharmacological interventions.

Prolonged intermittent theta burst stimulation targeting the left prefrontal cortex and cerebellum does not affect executive functions in healthy individuals

Repetitive transcranial magnetic stimulation (rTMS) for alleviating negative symptoms and cognitive dysfunction in schizophrenia commonly targets the left dorsolateral prefrontal cortex (LDLPFC). However, the therapeutic effectiveness of rTMS at this site remains inconclusive and increasingly, studies are focusing on cerebellar rTMS. Recently, prolonged intermittent theta-burst stimulation (iTBS) has emerged as a rapid-acting form of rTMS with promising clinical benefits. This study explored the cognitive and neurophysiological effects of prolonged iTBS administered to the LDLPFC and cerebellum in a healthy cohort. 50 healthy participants took part in a cross-over study and received prolonged (1800 pulses) iTBS targeting the LDLPFC, cerebellar vermis, and sham iTBS. Mixed effects repeated measures models examined cognitive and event-related potentials (ERPs) from 2-back (P300, N200) and Stroop (N200, N450) tasks after stimulation. Exploratory non-parametric cluster-based permutation tests compared ERPs between conditions. There were no significant differences between conditions for behavioural and ERP outcomes on the 2-back and Stroop tasks. Exploratory cluster-based permutation tests of ERPs did not identify any significant differences between conditions. We did not find evidence that a single session of prolonged iTBS administered to either the LDLPFC or cerebellum could cause any cognitive or ERP changes compared to sham in a healthy sample.

Information-based TMS to mid-lateral prefrontal cortex disrupts action goals during emotional processing

The ability to respond to emotional events in a context-sensitive and goal-oriented manner is essential for adaptive functioning. In models of behavioral and emotion regulation, the lateral prefrontal cortex (LPFC) is postulated to maintain goal-relevant representations that promote cognitive control, an idea rarely tested with causal inference. Here, we altered mid-LPFC function in healthy individuals using a putatively inhibitory brain stimulation protocol (continuous theta burst; cTBS), followed by fMRI scanning. Participants performed the Affective Go/No-Go task, which requires goal-oriented action during affective processing. We targeted mid-LPFC (vs. a Control site) based on the individualized location of action-goal representations observed during the task. cTBS to mid-LPFC reduced action-goal representations in mid-LPFC and impaired goal-oriented action, particularly during processing of negative emotional cues. During negative-cue processing, cTBS to mid-LPFC reduced functional coupling between mid-LPFC and nodes of the default mode network, including frontopolar cortex—a region thought to modulate LPFC control signals according to internal states. Collectively, these results indicate that mid-LPFC goal-relevant representations play a causal role in governing context-sensitive cognitive control during emotional processing.

Can pre-exercise photobiomodulation improve muscle endurance and promote recovery from muscle strength and injuries in people with different activity levels? A meta-analysis of randomized controlled trials.

Photobiomodulation therapy (PBMT) was introduced as an ergogenic aid for sport performance in healthy individuals is still controversial. The main aim of this study is to assess the potential enhancements in muscle endurance and recovery from muscle strength and injuries mediated by PBMT among individuals exhibiting diverse activity levels. Randomized controlled trials (RCT) of PBMT interventions for healthy people (both trained and untrained individuals) exercising were searched (up to January 16, 2024) in four electronic databases: Web of Science, PubMed, Scopus and Embase. Primary outcome measures included muscle endurance, muscle strength and creatine kinase (CK) levels; secondary outcome measure included Lactate dehydrogenase (LDH) levels. Subgroup analyses based on physical activity levels were conducted for each outcome measure. Thirty-four RCTs were included based on the article inclusion and exclusion criteria. Statistical results showed that PBMT significantly improved muscle endurance (standardized mean difference [SMD] = 0.31, 95%CI 0.11, 0.51, p < 0.01), indicating a moderate effect size. It also facilitated the recovery of muscle strength (SMD = 0.24, 95%CI 0.10, 0.39, p < 0.01) and CK (mean difference [MD] = -77.56, 95%CI -112.67, -42.44, p < 0.01), indicating moderate and large effect sizes, respectively. Furthermore, pre-application of PBMT significantly improved muscle endurance, recovery of muscle strength and injuries in physically inactive individuals and athletes (p < 0.05), while there was no significant benefit for physically active individuals. Pre-application of PBMT improves muscle endurance and promotes recovery from muscle strength and injury (includes CK and LDH) in athletes and sedentary populations, indicating moderate to large effect sizes, but is ineffective in physically active populations. This may be due to the fact that physically active people engage in more resistance training, which leads to a decrease in the proportion of red muscle fibres, thus affecting photobiomodulation.

Comparison of a portable, pneumotach flow-sensor–based spirometer (Spirofy™) with the vitalograph alpha Touch™ spirometer in evaluating lung function in healthy individuals, asthmatics, and COPD patients—a randomized, crossover study

BackgroundSpirofy™ is India’s first portable, pneumotach flow-sensor-based digital spirometer developed to diagnose asthma and chronic obstructive pulmonary disease (COPD). In this study, we compared the performance of the Spirofy™ device with that of the Vitalograph Alpha Touch™ spirometer in measuring the lung capacities of healthy individuals, asthmatics, and COPD patients. We also assessed the inter-device variability between two Spirofy™ devices.MethodsIn a randomized, three-way crossover, open-label study, we measured the differences in forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC) between the Spirofy™ and Vitalograph Alpha Touch™ spirometers. A proportion of the FEV1/FVC ratio distribution of < 0.7 was used to compare the diagnostic accuracies of the Spirofy™ with Vitalograph™ Alpha Touch™ spirometers.ResultsNinety subjects participated in this study. The mean ± SD FVC values obtained from the Spirofy™ 1, Spirofy™ 2, and Vitalograph Alpha Touch™ devices were 2.60 ± 1.05 L, 2.64 ± 1.04 L, and 2.67 ± 1.04 L, respectively. The mean ± SD FEV1 values obtained from the Spirofy™ 1, Spirofy™ 2, and Vitalograph Alpha Touch™ devices were 1.87 ± 0.92 (L), 1.88 ± 0.92 (L), and 1.93 ± 0.93 (L), respectively. A significant positive correlation was found between the FVC and FEV1 values recorded by Vitalograph Alpha Touch™, Spirofy™ 1, and Spirofy™ 2. As compared to Vitalograph Alpha Touch™, the Spirofy™ device showed good sensitivity (97%), specificity (90%), and overall accuracy (93.3%) at an FEV1/FVC ratio < 0.7. No inter-device variability was observed between the two Spirofy™ devices.ConclusionSpirofy™ is a portable and easy-to-use device and is as accurate as the standard Vitalograph Alpha Touch™ spirometer for the diagnosis of COPD and asthma.Trial registrationCTRI/2021/09/036492 (Clinical Trials Registry - India)

Effects of one-week bilateral cerebellar iTBS on resting-state functional brain network and multi-task attentional performance in healthy individuals: A randomized, sham-controlled trial

Background:Cerebellar intermittent theta burst stimulation (iTBS) modulates the excitability of the cerebral cortex and may enhance attentional performance. To date, few studies have conducted iTBS on healthy subjects for one week and used electroencephalography (EEG) to investigate the effect of multiple stimulation sessions on resting-state functional brain networks and the daily stimulation effect on attentional performance. Methods:16 healthy subjects participated in a one-week experiment, receiving bilateral cerebellar iTBS or sham stimulation and engaging in multi-task attentional training. The primary measures were the one-week attentional performance and pre- and post-experiment resting-state EEG activities. Amplitude Envelope Correlation (AEC) was used to construct the functional connectivity in the eye-open (EO) and eye-closed (EC) phases. Results:At least three sessions of iTBS were required to enhance multi-task performance significantly, whereas only one or two sessions failed to elicit the improvement. Compared with the control group, iTBS induced significant changes in PSD, AEC functional connectivity, and AEC network properties during the EO phase, while it had little effect during the EC phase. During the EO phase, the network property changes of the iTBS subject were correlated with improved attentional performance. Conclusion:The multi-task performance requires multiple stimulations to enhance. iTBS affects the resting-state alpha band brain activities during the EO rather than the EC phase. The AEC network properties may serve as a biomarker to assess the attentional potential of healthy subjects.

The associations among glycemic control, heart variability, and autonomic brain function in healthy individuals: Age- and sex-related differences

IntroductionThe purpose of this study was to clarify the relationships between glycemia and function of the autonomic nervous system (ANS), assessed via resting-state functional connectivity (FC) and heart-rate variability (HRV). MethodsData for this study were extracted from the Leipzig Study for Mind-Body-Emotion Interactions, including 146 healthy adults (114 young, 32 older). Variables of interest were glycated hemoglobin (HbA1c), resting-state FC in the salience aspect of the central-autonomic (S-CAN) and salience network (SN) and HRV (RMSSD and high-frequency HRV (HF-HRV)). ResultsHbA1c was inversely correlated with FC in the S-CAN but not SN. HbA1c was also inversely correlated with HRV (RMSSD and log(HF-HRV)). Both RMSSD and log(HF-HRV) were correlated with FC in the S-CAN and SN. Age- (not sex-related) differences were observed in the Hb1Ac-FC associations while sex- (not age-related) differences were observed in the HRV-FC. ConclusionsThese findings extend the diabetes literature to healthy adults in relating glycemia and brain function. The age- and sex-related differences in these relationships highlight the need to account for the potential effects of age and sex in future investigations.

SEX DIFFERENCES IN CEREBRAL BLOOD FLOW VELOCITY RESPONSES TO EXERCISE IN THE HEAT

INTRODUCTION &amp; AIMS Global warming poses a risk for the development of heat-related physiological impairment, which can be aggravated when exercising in hot conditions. The aim of the present study was to investigate acute effects of exercising in hot conditions on cerebral blood flow velocity and systolic function in healthy individuals and to explore possible sex differences. METHODS The experimental condition consisted of walking on a treadmill, at 5km/h and 2% incline, inside a heat chamber at 40°C (50%RH), for 90 minutes. Middle cerebral artery blood flow velocity (MCAv) and left ventricular global longitudinal strain (GLS; a sensitive index of systolic function), were assessed at baseline and every 30 minutes by means of transcranial Doppler and speckle-tracking echocardiography, respectively. Data is expressed in delta (Δ) and standard error. RESULTS Twenty-six individuals (13♂,13♀ 27.1±1.0yrs, P=0.02) completed the experimental protocol. Both males and females exhibited non-significant increases in MCAv from baseline at 30 minutes (♂Δ=2.55±2.15 P&amp;gt;0.05; ♀Δ=0.54±2.53cm.s-1, P&amp;gt;0.05; interaction P=0.63), followed by significant decreases relative to 30min, at 60min (♂Δ=-4.0±1.23 P=0.04; ♀Δ=-5.41±1.56cm.s-1, P=0.03; interaction P=0.63) and 90 minutes (♂Δ=-6.08±1.37 P&amp;lt;0.01; ♀Δ=-7.39±1.40cm.s-1, P&amp;lt;0.01; interaction P=0.63). In males, there was a significant decrease in GLS from baseline at 30min (Δ=2.44±0.69%, P&amp;lt;0.05), 60 (Δ=2.79±0.73%, P=0.03), and 90 (Δ=3.49±0.89%, P=0.03) minutes; no significant changes were observed in females. CONCLUSION Males and females presented similar patterns of change in cerebral blood flow velocity, including significant decreases with prolonged heat exertion. These changes occur in both sexes, despite changes in systolic strain only being apparent in males. These data suggest that sex differences may exist in the regulation of cerebrovascular responses to exercise in the heat in humans.

Reliability and validity of a novel mobile-based automatic battery of cognitive tests in healthy young Chinese adults

Purpose To evaluate the reliability and validity of a newly developed computerized Automated Battery of Cognitive Tests in healthy individuals without cognitive impairments or psychiatric disorders. Methods From April 20 to July 1, 2023, 142 healthy individuals in Beijing and Tangshan, China were assessed using the Automated Battery of Cognitive Tests. After a 3-week interval, 36 participants were randomly selected for retesting. The assessment also included administration of the Repeatable Battery for the Assessment of Neuropsychological Status and the Automated Battery of Cognitive Tests to 59 participants. Results The Automated Battery of Cognitive Tests consists of 16 subtests. Internal consistency reliability was 0.75. The test-retest reliability for each factor ranged from 0.337 to 0.850 (p < 0.05). The criterion-related validity, as measured by correlation with the total Repeatable Battery for the Assessment of Neuropsychological Status score, was 0.748 (p < 0.001). The cumulative variance contribution rate is 70.109%. The results of the confirmatory factor analysis indicated a good model fit. Conclusions The computerized Automated Battery of Cognitive Tests is a cognitive self-assessment tool with good reliability and validity. It can evaluate multiple aspects of cognitive performance in healthy individuals and is suitable for self-administration through remote access via Internet.

Peripheral inflammation is associated with impaired sadness recognition in euthymic bipolar patients

BackgroundInflammation impairs cognitive function in healthy individuals and people with psychiatric disorders, such as bipolar disorder (BD). This effect may also impact emotion recognition, a fundamental element of social cognition. Our study aimed to investigate the relationships between pro-inflammatory cytokines and emotion recognition in euthymic BD patients and healthy controls (HCs). MethodsWe recruited forty-four euthymic BD patients and forty healthy controls (HCs) and measured their inflammatory markers, including high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6), and TNF-α. We applied validated cognitive tasks, the Wisconsin Card-Sorting Test (WCST) and Continuous Performance Test (CPT), and a social cognitive task for emotion recognition, Diagnostic Analyses of Nonverbal Accuracy, Taiwanese Version (DANVA-2-TW). We analyzed the relationships between cytokines and cognition and then explored possible predictive factors of sadness recognition accuracy. ResultsRegarding pro-inflammatory cytokines, TNF-α was elevated in euthymic BD patients relative to HCs. In euthymic BD patients only, higher TNF-α levels were associated with lower accuracy of sadness recognition. Regression analysis revealed that TNF-α was an independent predictive factor of sadness recognition in patients with euthymic BD when neurocognition was controlled for.Conclusions: We demonstrated that enhanced inflammation, indicated by increased TNF-α, was an independent predictive factor of impaired sadness recognition in BD patients but not in HCs. Our findings suggested a direct influence of TNF-α on sadness recognition and indicated vulnerability to depression in euthymic BD patients with chronic inflammation.

Repetitive temporal interference stimulation improves jump performance but not the postural stability in young healthy males: a randomized controlled trial

BackgroundTemporal interference (TI) stimulation, an innovative non-invasive brain stimulation technique, has the potential to activate neurons in deep brain regions. The objective of this study was to evaluate the effects of repetitive TI stimulation targeting the lower limb motor control area (i.e., the M1 leg area) on lower limb motor function in healthy individuals, which could provide evidence for further translational application of non-invasive deep brain stimulation.MethodsIn this randomized, double-blinded, parallel-controlled trial, 46 healthy male adults were randomly divided into the TI or sham group. The TI group received 2 mA (peak-to-peak) TI stimulation targeting the M1 leg area with a 20 Hz frequency difference (2 kHz and 2.02 kHz). Stimulation parameters of the sham group were consistent with those of the TI group but the current input lasted only 1 min (30 s ramp-up and ramp-down). Both groups received stimulation twice daily for five consecutive days. The vertical jump test (countermovement jump [CMJ], squat jump [SJ], and continuous jump [CJ]) and Y-balance test were performed before and after the total intervention session. Two-way repeated measures ANOVA (group × time) was performed to evaluate the effects of TI stimulation on lower limb motor function.ResultsForty participants completed all scheduled study visits. Two-way repeated measures ANOVA showed significant group × time interaction effects for CMJ height (F = 8.858, p = 0.005) and SJ height (F = 6.523, p = 0.015). The interaction effect of the average CJ height of the first 15 s was marginally significant (F = 3.550, p = 0.067). However, there was no significant interaction effect on the Y balance (p > 0.05). Further within-group comparisons showed a significant post-intervention increase in the height of the CMJ (p = 0.004), SJ (p = 0.010) and the average CJ height of the first 15 s (p = 0.004) in the TI group.ConclusionRepetitive TI stimulation targeting the lower limb motor control area effectively increased vertical jump height in healthy adult males but had no significant effect on dynamic postural stability.

Impact of dietary habits on renal function in Saku, a rural Japanese town: a cohort study.

High protein intake leads to a decline in renal function in the advanced stages of chronic kidney disease (CKD). An effective diet for maintaining renal function in healthy individuals or patients in the early stages of CKD has not been established. This cohort study was conducted in Saku, Nagano Prefecture, Japan, to investigate the impact of dietary habits on renal function. In this cross-sectional cohort study, we used the Saku Control Obesity Program (UMIN000016892), including 4,446 participants who submitted a brief-type self-administered diet history questionnaire and underwent routine physical examination. The amount of food intake was divided into quartiles. After adjusting for age and sex, multivariate logistic regression analysis was used to calculate the odds ratio (OR) for the risk of developing CKD (estimated glomerular filtration rate [eGFR] < 60mL/min/1.73 m2). In total, 3,899 participants were analyzed. The overall prevalence of patients with eGFR < 60mL/min/1.73 m2 was 11% (n = 434, male; 7.1%, female; 4.1%). The groups with a high intake of chicken (approximately 63.4g/day, adjusted OR: 0.632, P = 0.003), natto (fermented bean; approximately 21.7g/day, adjusted OR: 0.679, P = 0.01), and plant protein (approximately 0.8g/ideal body weight/day, adjusted OR: 0.695, P = 0.042) showed a low risk of developing CKD compared to the group with the lowest intake. Our cross-sectional study showed that the intake of chicken meat, natto, and plant protein was associated with high eGFR levels. This information can be of value for preventing CKD incidence in healthy Japanese individuals.

Cryotherapy effects on knee proprioception and quadriceps performance in healthy college students

BACKGROUND: Cryotherapy is widely utilized for therapeutic purposes, yet its specific effects on knee joint proprioception and quadriceps muscle performance in healthy individuals remain unclear. This study addresses this gap by examining the impact of a 20-minute cryotherapy session on knee joint proprioception and related muscle parameters in a cohort of healthy college students. OBJECTIVES: To investigate the effects of cryotherapy on knee joint proprioception and quadriceps muscle peak moment, work and power in healthy college male and female students. METHODS: Thirty-two healthy students, aged 19–23, underwent a 20-minute cryotherapy session using Cryogel packs applied to the anterior thigh and knee. An isokinetic dynamometer measured knee joint proprioception and quadriceps muscle parameters before, immediately after, 10-min, and 20-min post-cryotherapy. RESULTS: Proprioception values did not significantly differ between genders or post-tests (p&gt; 0.05). However, the female group exhibited significantly lower moment, power, and work values compared to males (p&lt; 0.05). No significant differences were observed within or between post-tests in moment, power, and work for both genders (p&gt; 0.05). CONCLUSIONS: A 20-minute cryotherapy application demonstrated no adverse effects on knee joint proprioception or quadriceps muscle metrics in healthy college students, supporting the safety of cryotherapy in this context.

Association Between EEG Microarousal During Nocturnal Sleep and Next-Day Selective Attention in Mild Sleep-Restricted Healthy Undergraduates.

To explore whether sleep electroencephalogram (EEG) microarousals of different standard durations predict daytime mood and attention performance in healthy individuals after mild sleep restriction. Sixteen (nine female) healthy college students were recruited to examine the correlations between nocturnal EEG microarousals of different standard durations (≥3 s, ≥5 s, ≥7 s, ≥9 s) under mild sleep restriction (1.5 h) and the following morning's subjective alertness, mood, sustained attention, and selective attention task performance. Results revealed that mild sleep restriction significantly reduced subjective alertness and positive mood, while having no significant effect on negative mood, sustained attention and selective attention performance. The number of microarousals (≥5 s) was negatively associated with positive mood at 6:30. The number of microarousals was significantly and positively correlated with the response time difference value of disengagement component of the selective attention task at around 7:30 (≥5 s and ≥7 s) and 9:00 (≥5 s). The number of microarousals (≥7 s) was significantly and positively correlated with the inaccuracy difference value of orientation component of the selective attention task at around 9:00. The number of EEG microarousals during sleep in healthy adults with mild sleep restriction was significantly and negatively related to their daytime positive affect while positively associated with the deterioration of disengagement and orientation of selective attention performance, but this link is dependent on the standard duration of microarousals, test time and the type of task.

Clinical effect of phytosterol-enriched saw palmetto extract on urinary function in healthy middle-aged and older males: a double-blind, placebo-controlled randomized comparative study

Background: Saw palmetto extract (SPE) is one of the most widely used supplements for benign prostatic hyperplasia (BPH) due to its pharmacological effects. β-sitosterol-enriched saw palmetto oil (VISPO™) contains more than 3% β-sitosterol and 85% total fatty acids and has been shown to improve symptoms in patients with BPH. Lower urinary tract symptoms (LUTS) require primary preventive measures in countries with accelerated population aging, including Japan. VISPO™ is expected to be effective against the early symptoms of LUTS. However, the effect of VISPO™ on urinary function in healthy individuals has not been elucidated. Objective: This clinical study evaluated the efficacy and tolerability of VISPO™ in the management of urinary complaints among healthy middle-aged and older men who did not require treatment. Methods: We conducted a randomized, double-blind, placebo-controlled trial that included 54 male participants who were assigned to consume VISPO™ or placebo (olive oil) capsules for 12 weeks. Biometric data, uroflowmetry results, and salivary hormone levels were assessed at weeks 1 and 12. Urinary function and quality of life were assessed at weeks 1, 4, 8, and 12 using the International Prostate Symptom Score (IPSS), Overactive Bladder Symptom Score (OABSS), Core Lower Urinary Tract Symptom Score (CLSS), and WHOQOL-26. Results: Two-way analysis of variance revealed that IPSS and OABSS were significantly lower in the VISPO™ group that in the placebo group. However, there were no significant differences in urine volume, urinary flow rate, or salivary hormone levels. In addition, no participants reported adverse effects (diarrhea, abdominal pain, etc.). Conclusion: The results of the present study, which is the first randomized controlled trial of VISPO™ conducted among healthy participants, demonstrate the effectiveness of VISPO™ in the management of lower urinary tract complaints that do not require treatment. Trial Registration: University Hospital Medical Information Network Clinical Trials Registry (UMIN000046386). Keywords: saw palmetto, VISPO™, β-sitosterol, fatty acids, healthy subjects, primary preventive, IPSS, OABSS, lower urinary tract symptoms (LUTS)

Biomechanical effects of foot orthoses on jump landing performance: A systematic review

Jumping is involved in a wide range of sports and activities, and foot orthoses (FO) are suggested to enhance performance and prevent injury. The aim of this systematic review was to investigate whether using FO with different modifications affects jump landing biomechanics and improves performance in healthy individuals. The search strategy included 7 databases that identified 19 studies. The study quality was evaluated using a modified Downs and Black index. The primary outcome measures were joint kinematics, kinetics, muscle activity, vertical jump height, and horizontal jump distance. Our findings indicated that incorporating arch support with a rearfoot post and softer forefoot region into FO may improve several biomechanical variables during jump landing activities. Improvements in vertical ground reaction force loading rates, knee and ankle kinematics, and muscle cocontraction during jumping with FO could enhance jumping performance. In addition, improvements in hip, knee, ankle, and tibial kinematics and vertical ground reaction force loading rates during landing could reduce impact forces and related injuries. Although a limited number of studies have addressed the effects of FO on vertical jump height and horizontal jump distance, inserting such FO inside shoes with optimum bending stiffness could facilitate jumping performance. A rigorous exploration of the effect and mechanism of FO designs on jumping performance could benefit jumping-related activities and prevent ankle and knee injuries.

Circadian rhythm and variability of large and small airway spirometric variables in healthy individuals.

To assess the diurnal rhythm and variability of lung function in healthy individuals, encompassing both large and small airways. A prospective study enrolled 35 healthy adults without a history of smoking. Initial spirometry and a bronchodilation test were performed using the Jaeger spirometer, followed by a seven-day continuous home monitoring using the GOSPT2000. We evaluated repeatability using the intraclass correlation coefficient and agreement through linear regression and Bland-Altman analyses. Circadian rhythm and variability in spirometric measurements were analyzed using the coefficient of variation (CV) and daily variation rate. The GOSPT2000 demonstrated strong repeatability and high agreement with the Jaeger spirometer. Notable findings included a decrease in nocturnal forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV3 by 44, 59, and 53 mL, respectively. In contrast, peak expiratory flow at noon showed an increase of 0.143L/min. Small-airway variables, including forced expiratory flow at 50% and 75% of the FVC and maximum midexpiratory flow, showed no significant diurnal variation. The nocturnal CV for large-airway variables was ≤ 4%, while for small-airway variables, it was ≤ 11.89%. This study has established a spectrum of variability for both large and small airways in healthy populations. The variability of small-airway variables is higher than that of large-airway variables. The investigation into the diurnal rhythms and variability characteristics of both large and small airway variables in the healthy population can serve as a foundation for diagnosing asthma or assessing the efficacy of asthma treatments.

Black Soybean Seed Coat Extract Improves Endothelial Function and Upregulates Oxidative Stress Marker Expression in Healthy Volunteers by Stimulating Nitric Oxide Production in Endothelial Cells.

Black soybean seed coat extract (BE) contains multiple bioactive polyphenols, including flavan-3-ols and anthocyanins. BE improves endothelial function; however, it is unclear whether BE protects endothelial cells from senescence. In this study, we examined the effects of BE on endothelial cell senescence and vascular function in healthy individuals. High concentrations of glucose were used to induce senescence in bovine aortic endothelial cells incubated with BE. Senescence, vascular function, and oxidative stress markers were measured. Incubation with BE remarkably inhibited senescence-associated β-galactosidase and lactate dehydrogenase activities and dose dependently reduced intracellular reactive oxygen species levels in bovine aortic endothelial cells. BE treatment increased the levels of endothelial nitric oxide synthase (eNOS) mRNA and endothelial nitric oxide (NO) metabolites and increased the mRNA expression of klotho, a gene associated with an antiaging phenotype. To examine the effects of BE in humans, we conducted a clinical study using the second derivative of the fingertip photoplethysmogram to investigate vascular function and aging in 24 healthy volunteers. The participants consumed BE supplements (100 mg/day) or a placebo for 2 weeks. When compared with the placebo group, the BE group showed considerably improved vascular function, NO metabolite levels, and oxidative stress. These results suggest that BE supplementation improves endothelial function, possibly through antioxidant activity and NO production, and may consequently reduce the cardiovascular risk associated with aging. BE supplementation may be an effective and safe approach to reduce the risk of atherosclerosis and cardiovascular disease; however, additional studies investigating chronic vascular inflammation are needed.

Left atrial to ventricular volume ratio and relation to fitness, cardiovascular risk factors, and diastolic function in healthy individuals: the HUNT Study

Abstract Aims Left atrial (LA) and ventricular (LV) remodelling is thought to be balanced in healthy individuals, and the LA end-systolic volume (LAV) to LV end-diastolic volume (LVEDV) ratio (LA:LV) could help discriminate between pathological and physiological LA enlargement. We aimed to assess LA:LV and its associations with age, sex, and cardiovascular risk factors HbA1C, body mass index (BMI), systolic blood pressure, and peak oxygen uptake (VO2peak). The association to measures of LV diastolic function and filling pressures were compared with LAV and LA reservoir strain. Methods and results Cardiopulmonary exercise testing and measurement of risk factors 10 years apart and echocardiography at follow-up was performed in 1348 healthy adults [52% women, mean (SD) age 59 (12) years] prospectively included in a large population study. All risk factors were significantly associated with LA:LV in univariate analyses, while BMI and VO2peak were significantly associated with LA:LV in adjusted models. A higher LA:LV was associated with increased odds ratio (OR) of diastolic dysfunction [OR (95% CI) 2.6 (2.1, 3.3)]. Measures of LV filling pressures were more closely associated with LA:LV than LAV and LA reservoir strain, but LA reservoir strain was more closely related to some diastolic function measures. In individuals with LAV &amp;gt; 34 mL/m2, the LA:LV explained 29% of variance in VO2peak (P &amp;lt; 0.001). Conclusion A higher LA:LV was associated with, and may improve, assessment of diastolic dysfunction and filling pressures. The LA:LV differentiates VO2peak in individuals with enlarged LAV and may have a role in evaluating whether LA enlargement reflects pathology.

Increased Apolipoprotein B/Apolipoprotein A-I Ratio Is Associated With Decline in Lung Function in Healthy Individuals: The Kangbuk Samsung Health Study.

Lung dysfunction and high apolipoprotein B/apolipoprotein A-I (apoB/apoA-I) ratio are both recognized risk factors for cardiovascular disease. However, few studies have examined the association between the apoB/ApoA-I ratio and lung function. Therefore, we investigated whether this ratio is associated with decreased lung function in a large healthy cohort. We performed a cohort study on 68,418 healthy Koreans (34,797 males, mean age: 38.1 years) who underwent a health examination in 2019. ApoB/apoA-I ratio was categorized into quartiles. Spirometric values at the fifth percentile in our population were considered the lower limit of normal (LLN), which was used to define lung function impairment. Adjusted odds ratios (aORs) and 95% confidence intervals (CIs), using the lowest quartile as the reference, were estimated to determine lung function impairment. Mean apoB/apoA-I ratio was 0.67 ± 0.21. Subjects with the highest quartile of this ratio had the lowest predicted forced expiratory volume in one second (FEV1%) and forced vital capacity (FVC%) after controlling for covariates (P < 0.001). However, FEV1/FVC ratio was not significantly different among the four quartiles (P = 0.059). Compared with the lowest quartile (Q1, reference), the aORs (95% CI) for FEV1% < LLN across increasing quartiles (from Q2 to Q4) were 1.216 (1.094-1.351), 1.293 (1.156-1.448), and 1.481 (1.311-1.672) (P for trend < 0.001), respectively. Similarly, the aORs for FVC% < LLN compared with the reference were 1.212 (1.090-1.348), 1.283 (1.147-1.436), and 1.502 (1.331-1.695) with increasing quartiles (P for trend < 0.001). However, the aORs for FEV1/FVC < LLN were not significantly different among groups (P for trend = 0.273). High apoB/apoA-I ratio was associated with decreased lung function. However, longitudinal follow-up studies are required to validate our findings.