Search Results (2,907)

Background: Physical activity, sedentary behaviour, and sleep are interdependent components of the 24 h movement profile that may influence appetite control. While acute exercise can alter appetite perceptions and food reward, less is known about how reallocating time between daily behaviours affects appetite outcomes under free-living conditions. Methods: We applied isotemporal-substitution modelling in a cross-sectional study of 130 young, healthy, active adults. Accelerometer-derived estimates of sedentary time, light physical activity (LPA), moderate-to-vigorous physical activity (MVPA), and sleep were analysed in relation to energy intake (food diaries, laboratory meals), subjective appetite perceptions, appetite-related hormones (acylated ghrelin, PYY, leptin), and psychological traits, including food reward (Leeds Food Preference Questionnaire, LFPQ), food cravings (Control of Eating Questionnaire, CoEQ), and eating behaviour traits (Three-Factor Eating Questionnaire, TFEQ). Results: Reallocating 30 min/day of sedentary time to MVPA was associated with higher energy intake in free-living (+113 kcal/day, 95% CI: 34–192) and laboratory settings (+120 kcal/day, 95% CI: 55–185), along with greater postprandial hunger and prospective food consumption, reduced fullness, elevated fasting acylated ghrelin, and lower postprandial PYY. No associations were observed for reallocations to LPA or sleep. Furthermore, sedentary time reallocations were unrelated to leptin or psychological eating traits assessed by the LFPQ, CoEQ, or TFEQ. Conclusions: In this population, reallocating sedentary time to MVPA was linked to physiological and behavioural compensation consistent with elevated energy demands, whereas reallocating to LPA or sleep showed no associations. Trait-level eating behaviours were unaffected, suggesting MVPA influences appetite primarily through acute physiological rather than enduring cognitive or hedonic pathways. Full article

Calcium (Ca²⁺) signaling regulates a wide range of processes in the heart, from contractility and excitability to energy supply and cell growth. Consequently, Ca²⁺ signaling plays a critical role in cardiac adaptation to both physiological and pathophysiological stress. This review examines the role of Ca²⁺ signaling in the heart’s physiological adaptation to pregnancy and its pathological maladaptation in diabetes. We focus on Ca²⁺-dependent mechanisms involved in hypertrophy, energy imbalance, and electrical remodeling in these two conditions, highlighting shared signaling pathways, functional outcomes, and key knowledge gaps. A deeper understanding of these mechanisms could reveal novel therapeutic targets to improve cardiac health in pregnancy and diabetes. Full article

(1) Background: The global increase in life expectancy has generated growing interest in strategies that support functional independence and quality of life among older adults. Functional fitness—including strength, mobility, flexibility, and aerobic endurance—is essential for preserving autonomy during aging. In this context, physical exercise, particularly High-Intensity Interval Training (HIIT), has gained attention for its time efficiency and physiological benefits. This randomized controlled trial aimed to evaluate the effects of a group-based HIIT program on functional fitness in older adults; (2) Methods: Functional outcomes were assessed before, during, and after a 65-week intervention using standardized field tests, including measures of upper and lower body strength, flexibility, aerobic endurance, and agility. This study was prospectively registered at ClinicalTrials.gov (NCT07170579); (3) Results: Significant improvements were observed in the HIIT group across multiple domains of functional fitness compared to the control group, notably in upper body strength, lower limb flexibility, cardiorespiratory endurance, and mobility; (4) Conclusions: These results suggest that HIIT is an effective and adaptable strategy for improving functional fitness in older adults, with the potential to enhance performance in daily activities and support healthy aging in community settings. Full article

Root exudates are critical signaling molecules in belowground plant–plant interactions, regulating physiological and ecological responses in adjacent plants through kinship recognition and self-/non-self-discrimination systems. This review systematically synthesizes the compositional diversity of root exudates, with particular emphasis on elucidating the ecological foundations of plant recognition modalities (kin recognition, allelopathy, plant self-/non-self-identification, and growth regulation). The analyses demonstrate that exudate composition is dynamically modulated by plant species identity, rhizosphere microbial communities, and environmental stressors, with signaling functions mediated through both physical signal transduction and chemical signal decoding. This chemical communication system not only drives species-specific interaction strategies but redefines the theoretical frameworks of plant community assembly by establishing causal linkages between molecular signaling events and ecological outcomes. Full article

(1) Background: Low back pain (LBP) is the most prevalent cause of disability worldwide, yet current assessment relies mainly on subjective questionnaires, underscoring the need for objective and interpretable biomarkers. Bioelectrical impedance parameter (BIP), quantified by resistance (R), impedance magnitude (Z), and phase angle (PA), reflects tissue hydration and cellular integrity and may provide physiological correlates of pain; (2) Methods: This cross-sectional study used lumbar BIP and demographic characteristics from 83 participants (38 with lumbar BIP and 45 normal controls). We applied Extreme Gradient Boosting (XGBoost), a regularized tree-based machine learning (ML) algorithm, with stratified five-fold cross-validation. Model interpretability was ensured using SHapley Additive exPlanations (SHAP), which provide global importance rankings and local feature attributions. Outcomes included classification of LBP versus healthy status and regression-based prediction of pain scales: the Visual Analog Scale (VAS), Oswestry Disability Index (ODI), and Roland–Morris Disability Questionnaire (RMDQ); (3) Results: The classifier achieved high discrimination (ROC–AUC = 0.996 ± 0.009, sensitivity = 0.950 ± 0.068, specificity = 0.977 ± 0.049). Pain prediction showed best performance for VAS (R² = 0.70 ± 0.14; mean absolute error = 1.23 ± 0.27), with weaker performance for ODI and RMDQ; (4) Conclusions: These findings suggest that explainable ML models applied to BIP could discriminate between LBP and healthy groups and could estimate pain intensity, providing an objective complement to subjective assessments. Full article

Breastfeeding is a complex biological system and a bidirectional physiological dialogue in which the infant may contribute to maternal breast health. This review synthesizes current evidence, clearly separating established findings from emerging hypotheses, to examine the possible infant-driven mechanisms that influence hormonal and immune homeostasis in the mammary gland. We evaluate how neonatal suckling coordinates interconnected hormonal reflexes and immune activity, and we explore the hypothesis that the retrograde flow of infant saliva to the breast tissue could activate maternal enzymatic defenses, particularly the xanthine oxidase and lactoperoxidase systems. We also consider the activation of antimicrobial peptides through direct contact at the nipple and areola, including cathelicidin and defensins, as well as the potential roles of fetal microchimerism and microbial transfer from the infant’s mouth in strengthening breast resilience. Although much of the evidence remains indirect and based on in vitro and animal models, the convergence of data supports a reformulated conceptual model that presents the infant as an active physiological partner rather than a passive recipient of milk. Recognizing this shift has important clinical implications for the prevention of inflammatory conditions such as mastitis, the improvement of breastfeeding support strategies, and the optimization of maternal and infant health outcomes. The review also identifies significant gaps in current knowledge and cautiously proposes hypotheses to explore these mechanisms. While preliminary, this framework offers an original perspective that may guide future research and open new paths in the study of human lactation biology. Full article

Background: Basketball is characterized as a high-intensity, intermittent sport that places considerable demands on the cardiorespiratory, neuromuscular, and mechanical systems. These physiological requirements are modulated by contextual variables and the athlete’s stage of biological maturation, both of which significantly influence physical fitness outcomes. Consequently, it is imperative to employ age- and development-specific assessment protocols. Objectives: This study aimed to evaluate the differences in physical fitness across competitive categories and to explore the interrelationships among the various physical assessment tests. Twenty-four male players (U14 = 12; U16 = 12) participated in this research. Methods: Athletes were monitored using WIMUPRO inertial measurement units and completed the SBAFIT test battery to evaluate physical fitness parameters. Statistical analyses included both inferential and correlational approaches, with effect sizes calculated for all relevant variables. The independent variable was the competitive age category of the players. Results: The results indicated notable differences in physical performance between developmental groups, primarily attributed to biological maturation. Significant disparities were observed in measures of aerobic capacity, linear speed, agility, and centripetal force. Conclusions: The comparative nature of this study across developmental categories offers novel insights and practical implications for talent development and training optimization. Full article

Periodontal disease is a prevalent inflammatory disorder that can lead to severe oral complications. Recent studies increasingly underline the role of endoplasmic reticulum (ER) stress in its pathogenesis. Experimental models using inflammatory agents such as lipopolysaccharide (LPS), tumor necrosis factor-alpha (TNF-α), and ligature-induced periodontitis in rodents, as well as chemical hypoxia, have consistently demonstrated the activation of unfolded protein response (UPR) pathways in periodontal cells. Key ER stress markers, including CHOP, GRP78, PERK, and ATF6, were upregulated in periodontal ligament cells, stem cells, and gingival epithelial cells under these conditions. While ER stress in periodontitis is primarily associated with detrimental outcomes such as apoptosis and inflammation, it may also have a physiological role in bone remodeling via the PERK-eIF2α-ATF4 axis. Importantly, several ER stress-modulating agents—such as oridonin, melatonin, and exosomes derived from M2 macrophages—have shown therapeutic potential by reducing stress marker expression and limiting periodontal damage. These findings suggest that targeting ER stress may offer a novel therapeutic strategy. Future human studies are essential to determine whether a combined approach targeting inflammation and ER stress could more effectively halt or reverse periodontal tissue destruction, while also assessing the long-term safety of ER stress modulation. Full article

Ambient temperature and thermoregulation influence sleep quality. This study investigated the effects of a temperature-controlled mattress cover on sleep and perceptual outcomes in healthy adults. In a randomised, counterbalanced, crossover design, 34 healthy adults (20 F, 14 M; age, 30 ± 5 y) used a temperature-controlled mattress cover for 14 nights, following ≥3 nights of familiarisation. The temperature feature was on for 7 nights (POD) and off for 7 nights (CON). Sleep was assessed via wrist actigraphy, while heart rate (HR), heart rate variability (HRV), and respiratory rate (RR) were recorded by embedded sensors in the mattress cover. Participants completed daily and weekly questionnaires evaluating sleep quality, thermal comfort, and thermal sensation. Linear mixed models showed significant main effects of condition favouring POD over CON for all daily perceived outcomes (all p < 0.05). A large, significant improvement in perceived sleep quality was observed (p = 0.001, d = 0.92). No significant differences were found in objective sleep metrics or biometric measures (all p ≥ 0.05). A temperature-controlled mattress cover was associated with improved subjective sleep quality and thermal-related perceptions despite minimal changes in objective or biometric outcomes, which may in part reflect expectancy, or placebo effects. Further research is needed to explore whether these perceptual benefits lead to physiological improvements over time. Full article

This study reviews the scientific use of chest-strap wearables, analyzing their advantages and limitations, following PRISMA guidelines. Eligible studies assessed chest-strap devices in adults and reported physiological outcomes such as heart rate, heart rate variability, R–R intervals, or electrocardiographic waveform morphology. Studies involving implanted devices, wrist-worn wearables, or lacking validation against reference standards were excluded. Searches were conducted in PubMed, Scopus, Web of Science, and ScienceDirect for studies published in the last 10 years. The quality of the studies was assessed using the Mixed Methods Appraisal Tool, and results were synthesized narratively. Thirty-two studies were included. The most frequently evaluated devices were the Polar H10 and Zephyr BioHarness 3.0, which showed strong correlations with electrocardiography at rest and during light-to-moderate activity. Reported limitations included motion artefacts, poor strap placement, sweating, and degradation of the skin–electrode interface. None of the devices had CE or FDA approval for clinical use, and most studies were conducted in controlled settings, limiting generalizability. Ergonomic concerns such as discomfort during prolonged wear and restricted mobility were also noted. Overall, chest-strap sensors showed good validity and were widely used in validation studies. However, technical refinements and large-scale field trials are needed for broader clinical and occupational application. This review is registered in PROSPERO and is part of the SIREN project. Full article

The female reproductive system represents a highly complex regulatory network governing critical physiological functions, encompassing reproductive capacity and endocrine regulation that maintains female physiological homeostasis. The in vitro simulation system provides a novel tool for biomedical research and can be used as physiological and pathological models to study the female reproductive system. Recent advances in this technology have evolved from 2D and 3D printing to organ-on-a-chip (OOC) and microfluidic systems, which has emerged as a transformative platform for modeling the female reproductive system. These microphysiological systems integrate microfluidics, 3D cell culture, and biomimetic scaffolds to replicate key functional aspects of reproductive organs and tissues. They have enabled precise simulation of hormonal regulation, embryo-endometrium interactions, and disease mechanisms such as endometriosis and gynecologic cancers. This review highlights the current state of female reproductive OOCs, including ovary-, uterus-, and fallopian tube-on-a-chip system, their applications in assisted reproduction and disease modeling, and the technological hurdles to their widespread application. Though significant barriers remain in scaling OOCs for high-throughput drug screening, standardizing protocols for clinical applications, and validating their predictive value against human patient outcomes, OOCs have emerged as a transformative platform to model complex pathologies, offering unprecedented insights into disease mechanisms and personalized therapeutic interventions. Future directions, including multi-organ integration for systemic reproductive modeling, incorporation of microbiome interactions, and clinical translation for mechanisms of drug action, will facilitate unprecedented insights into reproductive physiology and pathology. Full article

Objectives: This study aimed to compare the clinical, functional, and radiological outcomes of three different fixation techniques—dorsal locking plate, crossed cortical screw, and a combination of both—used in first metatarsophalangeal (MTP) joint arthrodesis for advanced-stage hallux rigidus. The goal was to provide evidence-based guidance for surgical technique selection. Methods: This retrospective cohort study included 52 patients with advanced hallux rigidus (stage III–IV, Coughlin–Shurnas classification) who underwent surgical treatment between 2023 and 2025 at the Department of Orthopedics and Traumatology of Ankara Etlik City Hospital, with a minimum follow-up of one year. Patients were categorized into three groups according to the fixation technique used. Visual Analog Scale (VAS), American Orthopaedic Foot & Ankle Society (AOFAS) score, and Foot Function Index (FFI) were assessed using validated Turkish-language versions of the questionnaires. Radiological parameters included hallux valgus angle, first toe dorsiflexion angle, distal interphalangeal (DIP) arthritis, and radiographic union—defined as trabecular bridging across at least three cortices on weight-bearing anteroposterior and lateral radiographs. ANCOVA was performed with age as a covariate. Results: A total of 52 patients were included: Group 1 (dorsal plate fixation, n = 19), Group 2 (crossed cortical screw fixation, n = 16), and Group 3 (combined fixation, n = 17). Group 1 patients were significantly older (mean age: 64 ± 6 vs. 55 ± 6 and 59 ± 5 years; p < 0.001). After age adjustment, VAS pain scores were significantly higher in Group 1 compared to Group 3 (mean VAS: 2.8 ± 0.6 vs. 1.9 ± 0.5; p = 0.010). AOFAS scores did not differ significantly (p = 0.166), although Group 2 showed the highest median value (90 [70–93]). FFI scores differed significantly (p < 0.001), with Group 1 reporting worse outcomes (19 [17–31]) than Group 2 (15 [13–22], p = 0.03) and Group 3 (15 [11–16], p = 0.01). Dorsiflexion angle was significantly lower in Group 2 than Group 1 (median 19° vs. 27°; p = 0.04), though all remained within the physiological range. Radiographic union was achieved in 50/52 patients (96.2%), without significant intergroup differences (p = 0.612). Complications included two cases of wound dehiscence in Group 1; no infections, symptomatic non-union, malalignment, or hardware irritation were observed. Conclusions: Crossed cortical screw fixation yielded the most favorable functional outcomes, whereas the combined technique achieved the lowest postoperative pain scores. Dorsal plate fixation alone consistently underperformed. While outcomes were adjusted for age, residual confounding cannot be excluded. These results highlight the importance of tailoring fixation strategy to patient profile, with crossed screw and combined methods representing reliable choices for optimizing postoperative outcomes in advanced hallux rigidus. Full article

Spaceflight imposes unique physiological stressors that profoundly disrupt immune regulation, including impaired lymphocyte activation, latent viral reactivation, and chronic low-grade inflammation. While structured exercise is the cornerstone countermeasure for musculoskeletal and cardiovascular health, current protocols rarely integrate immune endpoints into their design. This review aims to synthesize current evidence on the immunological effects of exercise in spaceflight and propose a novel framework for immune-focused physical activity guidelines tailored to long-duration missions. Evidence indicates that exercise intensity and modality critically determine immune outcomes. Acute strenuous exercise may transiently suppress immunity via cortisol and reactive oxygen species pathways, whereas chronic moderate-to-vigorous training enhances immune surveillance, reduces systemic inflammation, and supports T-cell and NK-cell function. Exerkines such as IL-15, IL-7, and irisin emerge as central mediators of exercise-induced immunomodulation, with potential applications for spaceflight countermeasures. Incorporating immune health into exercise guidelines represents a necessary paradigm shift for astronaut care. A structured framework—emphasizing aerobic, resistance, and HIIT modalities; moderate-to-vigorous intensity; daily training; immune biomarker monitoring; and integration with nutrition and sleep—can enhance resilience against infection, viral reactivation, and cancer risk. Immune-focused countermeasures will be essential to safeguard astronaut health and ensure mission success on future deep-space expeditions. Full article

Background: Over the years, surgical techniques have evolved, resulting in an abundance of available procedures in the armamentarium of metabolic and bariatric surgeons, and the technology has also advanced in a similar way. Significant steps have been made in stapling technology especially, introducing artificial intelligence (AI) in optimizing this technology for better treatment outcomes. The introduction of AI in stapling technology showed a decrease in potential stapling complications not only in MBS, but also in other (surgical) specialties. Areas Covered: This review will cover the general principles of stapling in surgery, but with an emphasis on both the technical and anatomical considerations. We will also discuss the mechanisms of staplers and potential safety hazards. Finally, we will focus on how AI is integrated in stapling technology, potential pros and cons, and areas for future development of stapling technology and the integration of AI. Conclusions: In metabolic and bariatric surgery, stapling is a technical procedure that requires a comprehensive understanding of the anatomical and physiological characteristics of the target tissue. Variability in tissue thickness, vascularity, elasticity, and mechanical load, compounded by patient-specific factors and intraoperative dynamics, demands constant vigilance and adaptability from the surgeon. The integration of AI and digital technologies offers potential improvements in refining this process. By providing real-time feedback on tissue properties and supporting intraoperative decision-making, these tools can assist surgeons in optimizing staple-line integrity and minimizing complications. The ongoing combination of surgical expertise with intelligent technology may contribute to advancing precision stapling in metabolic and bariatric surgery. Full article

In addition to air temperature and personal factors, other weather quantities govern the outdoor human thermal perception. This study provides a new targeted approach for the evaluation of extreme events based on a specific multivariable bioclimate index. Heat waves (HWs) and outdoor human thermal stress (OHTS) events that occurred in downtown Rome (Italy) over the years 2018–2023 are identified, characterized, and compared through appropriate indices based on the air temperature for HWs and the Mediterranean Outdoor Comfort Index (MOCI) for OHTS events. The overlap between the two types of events is evaluated for each year through the hit (HR) and false alarm rates. The outcomes reveal severe traits for HWs and OHTS events and higher values of HR (minimum of 66%) with OHTS as a predictor of extreme conditions. This pilot investigation confirms that the use of air temperature threshold underestimates human physiological stress, revealing the importance of including multiple parameters, such as weather variables (temperature, wind speed, humidity, and solar radiation) and personal factors, in the assessment of hazards for the population living in a specific geographical region. This type of approach reveals increasingly critical facets and can provide key strategies to establish safe outdoor conditions for occupational and leisure activities. Full article