BackgroundSprint interval training (SIT) is widely used in competitive swimming, yet early post-exercise physiological and perceptual responses to different SIT configurations remain incompletely understood. This study compared in highly trained national-level middle- and long-distance swimmers. This study compared early post-exercise rating of perceived exertion (RPE), heart rate (HR), and blood lactate concentration (BLa) responses following four composite SIT configurations in national-level competitive middle- and long-distance freestyle swimmers.MethodsFifteen highly trained national-level swimmers participated in this randomized crossover study. Each participant completed four SIT configurations in randomized order, with a 7-day washout period between sessions: 12 × 25 m with 1-min recovery, 10 × 35 m with 80-s recovery, 8 × 50 m with 2-min recovery, and 6 × 75 m with 3-min recovery. The work-to-rest ratio was maintained at 1:4 across configurations. Rating of perceived exertion (RPE), heart rate (HR), and blood lactate concentration (BLa) were measured before exercise and immediately post-exercise and at 1, 3, 5, 7, and 9 min of recovery. Baseline-adjusted linear mixed-effects models were used to examine protocol, time, and protocol × time effects, with post-exercise time treated as a categorical factor.ResultsAfter adjustment for session-specific baseline values, significant main effects of protocol and time were observed for RPE, HR, and BLa (all p < 0.001). The protocol × time interaction did not reach statistical significance for RPE (p = 0.051) or HR (p = 0.209), A significant protocol × time interaction was observed for BLa (p = 0.005). BLa remained lower after SIT-1 than after SIT-2, SIT-3, and SIT-4 throughout recovery and decreased from 14.47 mmol·L-1 immediately post-exercise to 9.96 mmol·L-1 at 9 min, whereas BLa remained comparatively elevated after SIT-2 and SIT-3.ConclusionsAmong the four composite configurations, SIT-1 (12 × 25 m) produced the lowest early-recovery BLa, whereas SIT-2 (10 × 35 m) elicited the highest overall RPE and HR and, together with SIT-3, maintained the highest BLa. Coaches should therefore select the complete SIT set structure according to the desired acute metabolic and perceptual load and subsequent within-session recovery requirements, rather than considering repetition distance alone.
Division of labor in honey bees is accompanied by coordinated changes in neural and glandular physiology, yet the molecular links between neuromodulatory signaling and Major Royal Jelly Protein 1 (MRJP1) expression remain poorly understood. Here we show that the serotonin receptor Am5HTR2a is dynamically associated with nurse-bee physiology and MRJP1 expression in Apis mellifera. Among four serotonin receptor subtypes examined, Am5HTR2a showed the strongest age-dependent expression pattern. Expression peaked in the brain during the nurse stage (day 11) and slightly later in the hypopharyngeal glands (HG; day 16), where it rose from undetectable levels to a peak relative expression level of approximately 98, normalized to rp49, whereas the other receptor transcripts remained comparatively stable. Pharmacological manipulation showed that serotonin increased Am5HTR2a and MRJP1 expression in the brain and HG in a dose-dependent manner, whereas melatonin produced the opposite effect. A multifactorial general linear model identified pharmacological treatment as the dominant predictor of Am5HTR2a expression (F2,22 = 65.31, p < 0.001, partial η² = 0.856; n = 3 biological replicates per group), with a significant tissue × treatment interaction (F2,22 = 7.58, p = 0.003, partial η² = 0.408), indicating that serotonergic and melatonergic effects differed between neural and exocrine tissues. Consistently, endogenous serotonin depletion with 5,7-dihydroxytryptamine reduced MRJP1 expression. RNA interference-mediated knockdown of Am5HTR2a efficiently suppressed receptor transcript abundance and was accompanied by a progressive decline in MRJP1 mRNA. Notably, serotonin remained able to elevate MRJP1 expression in forager bees in a dose-dependent manner, indicating that serotonergic responsiveness persists beyond the nurse stage and that aspects of temporal polyethism remain physiologically reversible. Together, these results identify Am5HTR2a as a component of a serotonergic signaling pathway associated with worker bee physiology and HG-associated MRJP1 expression. The findings support a model in which serotonergic and melatonergic signaling are potentially linked to arylalkylamine N-acetyltransferase (AANAT)-dependent indoleamine metabolism, although AANAT activity was not directly measured here. In this framework, these signals help shape temporal polyethism by modulating molecular programs underlying worker allocation to behavioral and metabolic tasks.
Heat stress (HS) is a significant economic, welfare, and production burden to worldwide poultry production sustainability. Therefore, effective and sustainable mitigating strategies are needed. Driven by consumer’s changing preferences and demand for natural products, microalgae have attracted substantial attention from the poultry industry and have become the fastest growing segment of animal feed additives, yet their modes of action are still not well defined. This study aimed to determine the effect of Arthrospira platensis (Spirulina, SP) on growth performance in heat-stressed broilers and to delineate its underlying mechanisms by using in vivo and in vitro studies. Six hundred one-day old male Cobb500 chicks were randomly allocated to 12 environmental chambers (2 floor pens/chamber, 24 pens in total, 25 birds/pen) and fed two diets (standard control diet, C vs. SP-supplemented diet at 0.5% inclusion rate). On day 29, birds were exposed for two weeks to 2 environmental conditions (thermoneutral, TN, 24°C vs. cyclic HS 36°C, 8h/day). Growth performances, carcass parameters, and muscle myopathy incidences were determined. Chicken primary embryonic myoblasts (CPEM) were isolated, cultured, and treated with either benzoic acid (BA) or quercetin (QCT)-compounds abundant in SP- prior to a 6-h exposure to HS (45°C) or control conditions (37°C). Gene and protein expressions involved in protein proteostasis network (synthesis, degradation, and chaperonin) were measured by qPCR, immunoblot, and immunofluorescence. Data were analyzed by two-way ANOVA and Tukey test, and significance was set at P < 0.05. Heat stress significantly increased core body temperature (CBT) and water intake and depressed feed intake and growth performance in broilers. In-feed SP supplementation reduced CBT, improved water conversion ratio (WCR) by 36.5 points, and enhanced breast yield, without affecting muscle (woody breast and white striping) myopathies. Supplementation of SP significantly increased the phosphorylated levels of mTORSer2481, mTORSer2448, and S6KThr421/Ser424, decreased p-eIF2αSer51, ubiquitin, and HSP60/90 in heat-stressed broilers. Treatments of CPEM with BA or QCT recapitulated the effects of SP. Collectively, supplementation of SP enhanced breast yield in heat-stressed broilers through modulation of proteostasis network by enhancing protein synthesis (mTOR-S6K-eIF2α pathway), reducing protein degradation (ubiquitin machinery), and regulating chaperonins.
IntroductionCutaneous homeostasis is constantly perturbed by ultraviolet (UV) irradiation, which triggers extracellular matrix (ECM) structural derangement, fibroblast senescence, and the gradual deterioration of dermal integrity. CP161, a synthetic cyclic hexapeptide, has been documented to upregulate the transcription of collagen genes. Nevertheless, its broader cutaneous bioactivities as well as the precise molecular mechanisms underlying its skin-regulating effects remain largely unelucidated.MethodsWe first characterized the skin-protective potential of CP161 in primary human dermal fibroblasts (HDFs) exposed to ultraviolet radiation, relying on RT-qPCR, Western blot analysis, SA-β-gal staining and intracellular reactive oxygen species quantification for phenotypic validation. We utilized label-free quantitative proteomics to map core biological events and signaling networks altered following CP161 treatment, and adopted CETSA, BLI, molecular docking together with molecular dynamics (MD) simulations to verify whether CP161 can physically bind MAP2K1. We extended our investigation to cultured cholinergic neurons and PTZ-stimulated zebrafish larvae to further dissect CP161 biofunction; we quantified changes in acetylcholine (ACh) secretion and excessive neuromuscular activity in these two models, and similarly deployed CETSA, molecular docking and MD simulation assays to test for direct binding between CP161 and Munc18a.ResultsIn UVA-irradiated HDFs, CP161 restored COL1A1, COL14A1, and COL16A1 expression, suppressed MMP1 and p21 upregulation, reduced SA-β-gal-positive cells, and lowered intracellular ROS accumulation. Proteomic profiling revealed coordinated remodeling of ECM organization. CP161 attenuated UVA-induced MEK1/2–ERK1/2 phosphorylation, and CETSA, BLI, molecular docking, and MD analyses collectively supported direct interaction between CP161 and MAP2K1. In cholinergic neurons, CP161 reduced evoked ACh release; in PTZ-challenged zebrafish larvae, CP161 dose-dependently attenuated neuromuscular hyperactivity, and convergent biophysical and computational evidence supported direct interaction between CP161 and Munc18a, indicating a complementary activity relevant to contraction-associated mechanical injury of the dermis.ConclusionCP161 protects human dermal fibroblasts from UVA-induced damage through direct interaction with MAP2K1 and attenuation of the MEK1/2–ERK1/2 signaling cascade, thereby preserving ECM homeostasis. These findings establish a mechanistic framework for the skin-protective activity of CP161 and identify the MAP2K1–ERK1/2 axis as the principal pathway through which this cyclic hexapeptide maintains dermal homeostasis.
BackgroundExercise-mediated extracellular vesicle (EV)-derived non-coding RNAs (ncRNAs) contribute to cardiovascular protection, but a systematic synthesis of the field is lacking, and the evolution of research hotspots and knowledge structure remains unclear. This bibliometric study maps the research landscape, frontier hotspots, and emerging trends, while also interpreting the multi-target synergistic mechanisms underlying exercise-mediated cardioprotection based on published evidence.MethodsPublications were retrieved from the Web of Science Core Collection, PubMed, and Scopus from database inception to April 3, 2026. After deduplication and screening, 188 articles were included. VOSviewer, CiteSpace, and the R-based Bibliometrix package were employed for analyses of countries, institutions, journals, highly cited papers, and keywords.ResultsAnnual publications grew from 1 in 2013 to 28 in 2025. China (65 publications) and the United States (48 publications) together contributed over 60% of the total. Core journals included Frontiers in Physiology (11 publications), International Journal of Molecular Sciences (9 publications), and Cells (8 publications). Research evolved in three phases: early multi-directional exploration (2015–2020), a middle phase converging on EV-centric themes (2021–2023), and a recent return to fundamental biology (2023–2026). “Extracellular vesicles” ranked first in frequency (48 occurrences), while “physical activity” had the highest centrality (centrality 0.22). Ten keyword clusters were identified, with “aerobic exercise,” “animal model,” and “human cell” emerging as recent burst keywords. Mechanistically, informed by bibliometric patterns and published preclinical evidence, we propose that exercise may exert anti-apoptotic, antioxidant, anti-inflammatory, and anti-fibrotic effects by engaging a potential synergistic network involving EV-derived ncRNAs, though this framework requires experimental validation.ConclusionResearch in this field is transitioning from mechanistic exploration to clinical translation. China and the United States are the leading contributors, and the intersection of exercise intervention and EVs biology represents the most dynamic research direction. Future efforts should prioritize methodological standardization, large-scale clinical validation, and integration of artificial intelligence approaches, while addressing translational barriers in delivery, manufacturing, regulation, and clinical trial design.
ObjectiveThis study described post-traumatic growth (PTG), resilience (RI), and quality of life (QOL) in older adults hospitalized with hip fracture and examined their cross-sectional associations, including whether PTG statistically accounted for part of the association between RI and QOL.MethodsA cross-sectional convenience sample of 308 adults aged 60–90 years with hip fracture was recruited from an orthopedic ward, and 273 valid questionnaires were analyzed (effective response rate, 88.6%). Participants completed the General Information Questionnaire, the 20-item Chinese Post-traumatic Growth Inventory, the Connor-Davidson Resilience Scale, and the Short-Form 12 Health Survey. Associations were evaluated using Spearman correlation, covariate-adjusted linear regression with heteroskedasticity-consistent HC3 standard errors, and a 5,000-resample bootstrap mediation analysis.ResultsMedian (interquartile range) scores were 56 (49–60) for PTG, 71 (64–74) for RI, and 41.34 (37.90–44.22) for QOL. RI was positively correlated with PTG (rs=0.511) and QOL (rs=0.682), and PTG was positively correlated with QOL (rs=0.633; all p<0.001). In the fully adjusted QOL model, PTG (standardized β=0.302, p<0.001) and RI (standardized β=0.622, p<0.001) remained independently associated with QOL (R²=0.760; adjusted R²=0.745). The covariate-adjusted indirect association through PTG was 0.131 (bootstrap 95% CI, 0.086–0.175), representing 25.4% of the total RI–QOL association.ConclusionRI, PTG, and QOL were positively associated in this cross-sectional sample of older adults hospitalized with hip fracture. PTG statistically accounted for part of the RI–QOL association; however, the simultaneous measurement of all variables precludes causal or temporal interpretation. Longitudinal studies with detailed clinical covariates are required before intervention effects can be inferred.
The effects of high phytase levels on growth performance and calcium (Ca) and phosphorus (P) metabolism in broilers fed non-inorganic P diets were investigated. A total of 600 one-day-old broilers were assigned to either a control diet or a non-inorganic P diet supplemented with one of two commercial phytases (P1 and P2) at 1,000 (NP, normal level of phytase) or 10,000 FTU/kg (HP, high level of phytase). Compared with the control group, HP treatments had comparable feed intake, body weight gain and feed conversion ratio, whereas NP supplementation reduced the parameters, particularly during 22–42 and 1–42 days of age (p < 0.05). Both HP and NP treatments significantly increased apparent P retention during the finisher stage, compared with the control group (p < 0.01). At 42 days of age, compared with the control group, the HP chickens had higher tibial and femoral Ca contents (p < 0.01) and comparable P levels, whereas the NP chickens showed lower Ca and P contents (p < 0.01). High phytase levels increased blood concentrations of P and PTH, along with tibial and femoral lengths. Compared with the control group, phytase altered the expression of genes involved in Ca and P transport. NP treatment increased duodenal CaBP-D28k expression, while the P1 treatment at 1,000 FTU/kg significantly upregulated renal NPt2a and CaBP-D28k expression (p < 0.01). In conclusion, supplementation with 10,000 FTU/kg phytase to corn–soybean meal diet without inorganic P supplementation largely maintained growth performance and bone mineralization while improving P utilization and reducing P excretion. These findings indicate that 10,000 FTU/kg phytase can effectively replace inorganic P supplementation in broilers.
IntroductionA single bout of high-load resistance exercise can induce acute neuromuscular fatigue, necessitating effective recovery strategies to maintain explosive performance. However, the effects of foam rolling (FR) on vertical and horizontal jump performance and muscle excitation following fatiguing resistance exercise remain unclear. This study examined the acute effects of FR compared with passive recovery (PR) on vertical and horizontal jump performance and lower-extremity muscle excitation following a fatiguing resistance exercise protocol.MethodsThirty-one healthy, physically active men (age: 21.6 ± 1.3 years; body mass: 75.3 ± 10.3 kg; height: 180.6 ± 7.2 cm) completed a randomized crossover trial comparing FR and PR. Measurements were obtained at pre-test, immediately after exercise (mid-test), and after an 8-min recovery intervention (post-test). Jump performance was assessed using the countermovement jump (CMJ) and single-leg hop for distance (SLHD), while surface electromyography was recorded from the quadriceps, hamstrings, and gastrocnemius muscles during both tasks.ResultsA significant condition × time interaction was observed for CMJ and SLHD performance (p<.05; ηp2=.216−.256). Compared with PR, the FR condition showed improvements in CMJ (Δ = 6.23%; p = .004) and SLHD performance (Δ = 10.27%; p<.001) from mid-test to post-test. No significant condition × time interaction was found for normalized muscle excitation (p >.05; ηp2=.002−.070), although time-dependent changes were observed only in the rectus femoris and gastrocnemius muscles during the SLHD test (p<.05; ηp2=.187−.251).ConclusionThese findings indicate that FR facilitated the post-exercise restoration of vertical jump performance and produced an acute enhancement in horizontal jump performance following resistance exercise, yet the performance benefits were not accompanied by measurable changes in normalized muscle excitation. The results underscore the potential of FR as a practical recovery tool for improving functional performance, while the underlying physiological mechanisms remain uncertain.
Recirculatory aquaculture systems (RAS) are one of the most sustainable solutions for Nile tilapia, Oreochromis niloticus, production. Nitrogenous waste accumulation has been a major constraint to its usage, especially on water quality and fish health. Effects of Thiobacillus denitrificans on nitrogen removal, water quality, microbial abundance, and growth performance as well as the immunity of Nile tilapia cultured in RAS were examined in this study. Three treatments were prepared that comprised a control (CTR = no inoculation, standard biofiltration, and sulfur pellets as electron donor), a conventional nitrifying biofilter (CNB = enriched with Nitrosomonas and Nitrobacter (1.0 × 106 CFU mL-1)), and a T. denitrificans-inoculated biofilter (TDB = enriched with T. denitrificans (1.0 × 106 CFU mL-1) for 56 days). Results showed that total ammonia nitrogen (P = 0.001), nitrite (P = 0.001), and nitrate (P = 0.001) were greatly lowered in TDB compared to the CTR, with the lowest levels found in TDB and the highest levels found in CTR. Also, total suspended solids (P = 0.001) and chemical oxygen demand (P = 0.001) were significantly lower in TDB than in the CTR group. It is observed that fish on TDB had a considerably increased final body weight (+44.4%) and body weight gain (+49.2%) compared to the control. The addition of TDB in RAS used to raise Nile tilapia greatly (P = 0.001), increasing TP level accompanied by marked reduction in GLU (P = 0.001) and CHO (P = 0.024) and ALT (P = 0.021) levels. Antioxidant profiles, acetic viscosity, and butyric acid (P < 0.05) were significantly elevated in fish raised in RAS inoculated with the respective microbial treatments compared to the fish in the control group, as was gut histomorphometry. Also, immune profiles (respiratory burst activity, lysozymes, protease, and esterase activities) were significantly (P < 0.05) elevated in fish raised in TDB, while the least were observed in the control group. This study demonstrated that T. denitrificans improves nitrogen cycling and removal; water stability in RAS, which results in indirectly induced growth; and enhanced immunity in Nile tilapia, thus offering a promising biotechnological approach for sustainable aquaculture.
BackgroundMild Cognitive Impairment (MCI) represents a critical transitional stage between normal cognitive aging and dementia, characterized by a high conversion rate to Alzheimer’s disease (AD). Current pharmacological interventions provide limited symptomatic relief and do not alter disease trajectory. Consequently, there is an urgent need for effective, multimodal, non-pharmacological interventions. While repetitive Transcranial Magnetic Stimulation (rTMS) and Dance Movement Intervention (DMI) individually show promise in mitigating cognitive decline, their combined synergistic effects in older adults remain uninvestigated. This protocol outlines a randomized controlled trial to evaluate the clinical efficacy of combining rTMS with a culturally tailored DMI (Chinese square dancing) for older adults with MCI.MethodsThis study is designed as a four-arm, single-blinded, parallel-group randomized controlled trial. We aim to recruit 160 community-dwelling older adults (aged 50–85 years) diagnosed with MCI. Participants will be randomly allocated (1:1:1:1) to one of four groups: Combined Intervention (active rTMS + DMI), rTMS Only (active rTMS + social control), DMI Only (sham rTMS + DMI), or a Control Group (sham rTMS + social control). The 12-week intervention phase utilizes intermittent theta burst stimulation (iTBS) targeted at the left dorsolateral prefrontal cortex (DLPFC) and a structured Chinese square dancing program. Assessments occur at baseline, 12 weeks (post-intervention), and 24 weeks (follow-up). The primary outcome is global cognitive function, measured by the Montreal Cognitive Assessment (MoCA). Secondary outcomes assess memory, executive function, electroencephalography (EEG) biomarkers of neuroplasticity (P300), physical performance, and quality of life.DiscussionThis factorial trial will comprehensively evaluate the individual and interactive effects of neuromodulation and physical-cognitive training. By hypothesizing that rTMS will effectively prime cortical excitability to maximize the benefits of the complex sensorimotor demands of DMI, this study aims to establish a scalable, evidence-based multimodal therapy to delay cognitive decline in aging populations.
BackgroundThis study compared the effects of short-distance sprint training (SST) and long-distance sprint training (LST), under matched total training volume, on sprint performance, change-of-direction (COD) performance and intermittent aerobic endurance in collegiate basketball players.MethodsThirty male collegiate basketball players were stratified by playing position before being randomly assigned to either the SST group (n = 15) or the LST group (n = 15). Both groups completed a 6-week sprint training intervention twice weekly. Before and after the intervention assessments included sprint performance (5 m, 10 m, 20 m, and 30 m sprint tests), COD performance (505 test, T-test, and COD deficit (CODD)), and intermittent aerobic endurance (Yo-Yo Intermittent Recovery Test Level 1 (Yo-Yo IR1)). Rating of perceived exertion (RPE) was monitored throughout the intervention. Data were analyzed using one-way analysis of variance and two-way repeated-measures ANOVA.ResultsA significant group × time interaction observed only for 5 m sprint performance (F = 7.99, p = 0.022, η²p = 0.222). No significant interaction effects or group main effects were observed for the remaining sprint, COD, intermittent aerobic endurance, or RPE variables (p > 0.05). However, significant time main effects were found for 10 m, 20 m, and 30 m sprint performance, 505 test, T-test, CODD, and Yo-Yo IR1 (p < 0.05), indicating that both training protocols improved these outcomes over time. Although the SST group showed descriptively greater percentage improvements in 5 m and 10 m sprint performance, and the LST group demonstrated larger percentage improvements in 20 m and 30 m sprint performance, COD performance, and Yo-Yo IR1, these differences were not statistically significant. RPE responses were similar between groups throughout the intervention.ConclusionsUnder matched training volume conditions, both SST and LST effectively improved sprint, COD, and intermittent aerobic endurance performance after 6 weeks in male collegiate basketball players. SST elicited significantly greater improvements only in 5 m sprint performance, whereas both training protocols produced comparable improvements in the remaining outcomes. Our findings suggest that sprint distance is a meaningful programming variable that may shape basketball-specific physical adaptations.Clinical trial registrationhttps://www.chictr.org.cn, identifier ChiCTR2600122073.
IntroductionElectroencephalogram (EEG)-based fatigue classification is important for vigilance monitoring. Reliable recognition remains challenging due to fatigue-related neural changes that involve both spectral-temporal dynamics and altered inter-channel interactions. MethodsThis study develops a lightweight Dual-Branch Multidimensional Attention Fusion Network (DB-MDAFNet) that integrates spectral-temporal features and PCC-derived inter-channel dependency representations for EEG-based fatigue classification. The framework uses differential entropy features extracted from five canonical EEG frequency bands as input. A parameter-free multidimensional enhancement (PF-ME) module is applied for feature recalibration. It then extracts complementary representations via a Channel Attention-Multi-scale Temporal (CA-MT) branch and a Functional Connectivity-Topological Encoding (FC-TE) branch derived from Pearson correlation coefficients (PCC). The fused representation is used to classify EEG samples into alert, tired, and drowsy states. Experiments were conducted on the public SEED-VIG dataset and the self-constructed video game-based fatigue dataset (DVG). ResultsUnder identical subject-dependent settings, DB-MDAFNet achieved 85.58% accuracy on SEED-VIG and 97.12%–98.56% accuracy on DVG datasets. The model maintained a compact architecture, with 0.185 M parameters under the DVG input configuration. Ablation results indicated the complementary contribution of the two branches. Model interpretability analyses suggested that the learned representations contained spatially structured patterns across frontal, parietal, and occipital electrode regions. DiscussionThe proposed framework, integrating multi-scale temporal learning with connectivity-derived topological encoding, provides a lightweight and interpretable architecture for EEG-based fatigue monitoring.
ObjectiveThis study developed and evaluated a machine learning model for predicting oxygen uptake (VO2) in dragon boat athletes using wearable signals and compared performance across signal combinations and device groups.MethodsTwelve male collegiate dragon boat athletes completed nine tests grouped into six task types (T1–T6): 200-, 500-, and 1000-m all-out paddling tests; an incremental test; a five-stage constant-load test; and four supramaximal-intensity tests pooled as T6. Heart rate, respiratory rate, device-derived minute ventilation, and muscle-oxygenation signals were collected. Fifteen signal combinations (G1–G15) and six device groups (A–F) were evaluated using a multilayer perceptron model. Performance was assessed using mean absolute error (MAE) and root mean square error (RMSE), with mean absolute percentage error (MAPE) also reported.ResultsG13–G15 showed comparable performance, with no significant differences. G14 yielded the lowest MAE and MAPE (2.21 mL·kg−1·min−1 and 9.48%), whereas G13 yielded the lowest RMSE (3.19 mL·kg−1·min−1). No significant differences were observed among signal combinations within Groups A, C, D, E, or F. Group F showed the lowest MAPE but did not differ significantly from Group B, whereas Group C showed significantly higher MAPE than Groups B, D, E, and F. Performance did not differ significantly across exercise tasks. During the 1000-m test, predicted and measured VO2 were strongly correlated for G15 (r = 0.88), with a mean prediction error of 0.44 mL·kg−1·min−1 and descriptive 95% limits of agreement from −6.32 to 7.20 mL·kg−1·min−1.ConclusionCardiorespiratory signals provided useful information for wearable-based VO2 prediction, whereas the contribution of muscle-oxygenation signals depended on the input configuration. G13–G15 should be regarded as comparably performing configurations, and bilateral muscle-oxygenation monitoring was not consistently superior to unilateral monitoring. Multimodal wearable signals show potential for non-invasive VO2 monitoring in dragon boat athletes, although larger samples and independent validation are required.
IntroductionThe International Space Station maintains normoxic atmospheric conditions of 14.7 psia (101 kPa) and 21% oxygen. Astronauts don spacesuits to conduct extravehicular activities (EVAs), which operate at a reduced pressure of 4.3 psia (29.6 kPa), and a hyperoxic atmosphere of 100% oxygen. The reduction in pressure presents a risk of decompression sickness and is mitigated by a several hour denitrogenation (aka, prebreathe) protocol. To reduce the time required for prebreathe, future lunar and planetary exploration habitats and vehicles are expected to maintain a hypobaric, mildly hypoxic habitable environment in order to facilitate faster transitions to hypobaric hyperoxic EVAs. Among other things, hypoxic environments can influence oxidative stress and alter glucose metabolism, or other adaptive remodeling.MethodsThree 11-day chamber study missions (n=8/mission) were conducted to characterize the effects of alternating a mildly hypoxic living environment [8.2-9.6 psia (56.5 – 66.2 kPa)/28.5-34% oxygen] with hyperoxic EVAs [4.3 psia (29.6 kPa)/85-95% oxygen]. Fasting blood and 24-h urine samples were collected before the mission, and then again before and after EVAs on mission days (MD) 3 and 7, and a final collection on MD10.ResultsSignificant fluctuations of iron, amino acid, and glucose metabolism, along with changes in adaptive responses including some oxidative stress were observed before and after hyperoxic EVA simulations.DiscussionBased on these findings, it is evident that the effects of alternating hypoxia and hyperoxia may alter metabolism and physiology during exploration-class space missions.
Mitochondrial retrograde signaling serves as a critical communication axis that links mitochondrial dysfunction to nuclear gene expression, shaping key pathways in gastric carcinogenesis. Gastric tumors frequently exhibit somatic mtDNA mutations, impaired oxidative phosphorylation, and elevated reactive oxygen species (ROS), collectively driving transcriptional reprogramming through activation of NF-κB and stabilization of HIF-1α. These retrograde signals promote inflammation, metabolic reprogramming, and resistance to apoptosis, ultimately reinforcing the Warburg phenotype characterized by enhanced aerobic glycolysis and lactate production. This review synthesizes current evidence on how mtDNA mutations, ROS-dependent transcription factor activation, and mitochondrial–nuclear metabolic crosstalk converge to promote malignant transformation. By integrating insights from mitochondrial biology, cancer genetics, and metabolic regulation, we outline a mechanistic framework that highlights mitochondrial retrograde signaling as a promising therapeutic target in gastric cancer.
The domesticated silkworm Bombyx mori is both a major sericultural species and a powerful model for studying how environmental cues are converted into developmental decisions. A central seasonal trait in this species is embryonic diapause, a maternally programmed developmental arrest whose incidence is shaped by genetic background and environmental conditions experienced during the maternal generation. Recent genome-editing studies have provided new functional evidence for the role of circadian clock genes in this process, particularly the two silkworm cryptochromes, BmCRY1 and BmCRY2. BmCRY1 belongs to the Drosophila-type CRY lineage and retains features consistent with a light-input function, whereas BmCRY2 belongs to the mammalian-type insect CRY lineage and displays structural motifs expected for a nuclear transcriptional repressor. Loss of Bmcry1 disrupts embryonic hatching and adult eclosion rhythms and impairs photoperiodic modulation of diapause, while temperature-dependent diapause induction under constant darkness is largely retained. By contrast, Bmcry2 mutants show reduced temperature-dependent diapause induction, although the direct role of BmCRY2 in the silkworm clockwork remains unresolved. Together, available evidence suggests that BmCRY1 and BmCRY2 act through distinct clock-related entry points that ultimately influence, directly or indirectly, the neuroendocrine pathway controlling diapause hormone release and maternal diapause commitment. These findings place silkworm cryptochromes at a key interface between environmental sensing, circadian timing and seasonal developmental control, with potential implications for sericulture.
This study evaluated the applicability and effectiveness of PhysioExercise GPT, an artificial intelligence tool based on the ChatGPT architecture, developed to support the teaching of exercise physiology to undergraduate physical education students. A longitudinal quasi-experimental study was conducted involving a total of 64 students. Thirty-two students used the AI tool through a structured educational approach that incorporated personalized support, immediate feedback, and learning activities based on Bloom’s Taxonomy, while a control group of 32 students received traditional instruction. The results showed that both groups improved over time; however, the AI-assisted group achieved significantly greater learning gains (p = 0.002). The intervention group demonstrated a mean improvement of 3.38 points compared with 1.97 points in the control group, corresponding to a large effect size (Hedges’ g = 0.80). Analysis of covariance (ANCOVA) confirmed that the superiority of the AI-assisted group remained significant after adjusting for baseline performance. The findings indicate that the structured use of PhysioExercise GPT functions as an effective digital tutor, promoting active learning and enhancing the retention of complex concepts. Although the study has limitations, including the absence of randomization, the results suggest that AI represents a robust complementary educational tool capable of improving academic performance in health education.
BackgroundCardiovascular disease constitutes a leading cause of morbidity and mortality among women following menopause, with triglyceride (TG) dysregulation serving as a critical pathophysiological contributor. Despite accumulating evidence supporting the efficacy of structured exercise interventions, consensus regarding the optimal modality and “dose” required to maximize TG reduction in this demographic remains elusive.MethodsWe systematically searched PubMed, Scopus, The Cochrane Library, Web of Science, CNKI, Wanfang Database, Weipu Database, and Chinese Biomedical Database through December 2025. Eligible studies comprised randomized controlled trials (RCTs) enrolling postmenopausal women, comparing aerobic exercise (AE), combined exercise (CE), resistance training (RT), high-intensity interval training (HIIT), and control (CON). A random-effects model was employed for network meta-analysis (NMA), computing mean differences (MD) and 95% credible intervals (CrI). Treatment hierarchies were established via surface under the cumulative ranking curve (SUCRA). Exercise doses were standardized to metabolic equivalent task minutes per week (MET-min/week), and a dose-response meta-analytic framework was applied to characterize potential non-linear relationships between exercise volume and TG modification.Results51 RCTs encompassing 2,046 participants were included. Network meta-analysis demonstrated that HIIT (MD: −0.23 mmol/L, 95% CrI: −0.44 to −0.03), AE (MD: −0.20 mmol/L, 95% CrI: −0.27 to −0.13), and CE (MD: −0.17 mmol/L, 95% CrI: −0.31 to −0.03) significantly reduced TG relative to CON, whereas RT did not reach statistical significance (MD: −0.10 mmol/L, 95% CrI: −0.25 to 0.05). SUCRA rankings identified HIIT as the most efficacious intervention (79.44%), followed by AE (73.03%), CE (60.63%), and RT (34.16%), though the HIIT estimate was based on only three studies and is therefore uncertain. Dose-response modeling suggested a non-linear association between exercise volume and TG reduction, with tentative optimal therapeutic ranges: HIIT at 1,000–1,300 MET-min/week, AE at 830–1,000 MET-min/week, and CE at 830–1,200 MET-min/week, beyond which effects appeared to plateau.ConclusionsThis investigation provides preliminary evidence suggesting a non-linear dose-response relationship between exercise volume and TG reduction in postmenopausal women. HIIT demonstrated the highest relative efficacy in SUCRA rankings, though this conclusion is based on limited evidence and wide credible intervals. All active interventions produced clinically meaningful TG lowering within tentative dose ranges, but the observed non-linear pattern should be interpreted cautiously given the low-to-moderate certainty of evidence. These findings challenge the simplistic “more is better” paradigm and offer hypothesis-generating guidance for precision exercise prescription, pending confirmation by future high-quality RCTs.
IntroductionPreoperative estimation of non-gross-total resection (non-GTR), as defined on early postoperative magnetic resonance imaging (MRI), may support patient counseling and postoperative surveillance planning after surgery for nonfunctioning pituitary neuroendocrine tumors (NF-PitNETs). We evaluated whether a clinically informed, interpretable preoperative modeling strategy improved risk estimation compared with a reference strategy.MethodsWe retrospectively analyzed 354 first-surgery patients from a single center with a documented early postoperative MRI-based resection-status endpoint; 57 (16.1%) had non-GTR. A prespecified clinically informed logistic strategy extended a reference model based on routine preoperative clinical and MRI variables by adding transformed terms representing nonlinear tumor burden and invasion severity. Models underwent stratified repeated nested cross-validation with five outer folds repeated 20 times and four-fold inner tuning. Performance was evaluated using patient-level averaged held-out predictions.ResultsUnder model-specific tuning strategies, the clinically informed strategy showed little change in discrimination compared with the reference strategy (area under the receiver operating characteristic curve, 0.8054 vs. 0.8022; area under the precision-recall curve, 0.4603 vs. 0.4534), but had a lower Brier score (0.1100 vs. 0.1480) and calibration closer to ideal (intercept, 0.0256 vs. −0.3778; slope, 1.0209 vs. 2.5233). It also showed greater model-based net benefit across an exploratory threshold range of 0.05–0.50 and separated cohort-derived tertiles with observed non-GTR rates of 4.2%, 8.5%, and 35.6%. Postoperative pathological variables provided little incremental value.DiscussionThese findings represent single-center internal validation of complete modeling strategies. Because the strategies differed in both predictor representation and tuning objective, the calibration difference cannot be attributed to the transformed predictors alone. Independent external validation using standardized postoperative MRI, together with uniform-tuning and reduced-model sensitivity analyses, is required before application to counseling or surveillance planning.
IntroductionThe hamstrings are essential for sports and daily activities, yet high stiffness and reduced flexibility increase injury risk. Existing relaxation techniques may be ineffective or impractical in clinical settings. This study investigated the immediate effects of radial extracorporeal shock wave therapy (rESWT) on hamstring stiffness and flexibility in individuals with hamstring tightness, providing preliminary evidence for its therapeutic potential for hamstring tightness.MethodsIn total, 131 participants with hamstring tightness were randomized to receive either active rESWT (n = 66) or sham control intervention (n = 65). Flexibility was assessed using the sit-and-reach test (SRT), active knee-extension test (AKE), and active straight leg raising test (ASLR), measured pre-intervention and 5 minutes post-intervention. Muscle stiffness was measured using MyotonPRO at 25% (upper), 50% (middle), and 75% (lower) of the line connecting the ischial tuberosity and the medial/lateral femoral epicondyles, evaluated pre-intervention, immediately post-intervention, and 5 minutes post-intervention.ResultsFor flexibility, the rESWT group demonstrated significant, large-effect improvements in SRT (|r| = 0.738) and ASLR (|r| = 0.848) performance, along with a reduction in knee-extension deficit (AKE, |d| = 1.584) (all PFDR < 0.001). The control group improved significantly only in SRT (PFDR = 0.008, moderate effect |r| = 0.350). Between-group comparisons revealed significantly greater improvements for rESWT in all three measures (all PFDR < 0.001; moderate-to-large effects: SRT |δ| = 0.373, AKE |d| = 1.858, ASLR |δ| = 0.683). Notably, post-intervention SRT raw scores reflecting final performance showed no significant between-group difference (PFDR = 0.091). Regarding muscle stiffness, significant group × time interactions with large effects occurred across all hamstring sits (all PFDR < 0.001, η² = 0.200-0.410). Both groups exhibited significantly reduced stiffness immediately post-intervention (all PFDR < 0.001); however, only the rESWT group maintained significant reductions at 5 minutes post-intervention (all PFDR < 0.001). The rESWT group exhibited significantly lower stiffness than the controls both immediately and 5 minutes after intervention at the 50%/75% semitendinosus and 75% biceps femoris (all PFDR < 0.05).ConclusionrESWT produces immediate and 5-minute short-term reductions in mid-to-lower hamstring stiffness and improves hamstring flexibility, suggesting potential for the immediate management of hamstring tightness.
