Frontiers in Physiology最新文献

Introduction: The wound healing in diabetes is hindered and prolonged due to long-term inflammation, oxidative stress damage, and angiogenesis disorders induced by high glucose status. The management of such difficult-to-treat wounds continues to pose a significant challenge in clinical treatment. Dietary nitrate, commonly found in greens such as beets and spinach, acts as a nutritional supplement and is metabolized in the body through the salivary nitrate-nitrite-NO pathway. This pathway plays a crucial role in various physiological functions, including enhancing blood flow and attenuating inflammation.

Methods: In this study, we established a diabetic rat wound model. Forty-eight rats were randomly divided into six groups (n = 8): the Con group, the Con + Nitrate group, the STZ group, the STZ + NaCl group, the STZ + rhEGF group, and the STZ + Nitrate group. Skin wound healing was assessed on the day of surgery and on postoperative days 3, 7, 10, and 14. Specimens were taken on days 7 and 14 post-surgery for relevant tests.

Results: We found that dietary nitrate could accelerate skin wound healing by promoting angiogenesis and increasing blood perfusion. Significantly, dietary nitrate also regulated glucose and lipid metabolism and exhibited anti-inflammatory and antioxidant properties.

Discussion: These findings provide a novel theoretical basis for managing wounds in diabetic individuals, indicating the broad potential of dietary nitrate in future clinical applications.

Active physiotherapy (APT) embraces a patient-centered approach, prioritizing self-management within the biopsychosocial model and involving active patient movements. Beyond structured exercise, APT incorporates pain neuroscience education, Mulligan Mobilization (MWM), and active myofascial release techniques to integrate sensory-motor information for functional recovery and pain relief. This study aims to rigorously compare the effectiveness of APT versus conventional physical therapy (CPT) on pain and functional outcomes in patients with chronic knee pain. Eighty-seven patients with symptomatic and radiographically confirmed knee pain were included in this 12-month follow-up of a randomized controlled trial, conducted at a national institute and a rehabilitation clinic. Patients were randomized to either APT (n = 44) or CPT (n = 43). The APT protocol integrated pain neuroscience education, MWM, active myofascial release techniques, and structured exercises focusing on flexibility, stability, neuromuscular control, and coordination. The CPT protocol included health education, laser therapy, ultrasound therapy, and exercise. Both interventions were performed for 60 min twice a week for 3 months. The primary outcome was the Knee Injury and Osteoarthritis Outcome Score-4 domain version (KOOS4). Secondary outcomes included pain intensity (VAS), KOOS-pain, activities of daily living (ADL), function in sport and recreation (Sports/Rec), knee-related quality of life, global rating of change (GROC), quality of life (SF-36), Tampa Scale for Kinesiophobia (TSK), and functional performances measured at different intervals. Intention-to-treat analyses were performed. Of the 87 patients, 70 (80.5%) completed the 12-month follow-up. KOOS4 improved more in the APT group (16.13; 95% CI, 10.39-21.88) than in the CPT group (11.23; 95% CI, 5.42-17.04). APT showed additional improvement in KOOS4 compared to CPT (2.94; 95% CI: 0.04 to 5.85, p = 0.047). The VAS difference was -3.41 mm (95% CI: -6.40 to -0.43, p = 0.025), favoring APT. APT also showed more improvements in KOOS-pain, KOOS-ADL, KOOS-Sports/Rec, and TSK (p < 0.05). No differences between groups were observed in GROC and SF-36. APT significantly improved most functional performance variables compared to CPT (p < 0.05). Active Physiotherapy outshines conventional physical therapy by delivering more substantial reductions in pain intensity and marked enhancements in function among patients with knee pain. This distinctive efficacy underscores the invaluable role of APT in the management of chronic knee pain. By actively involving patients in their recovery journey, APT not only fosters superior results but also emphasizes the critical need to integrate these advanced therapeutic strategies into everyday clinical practices.

Repetitive variations, such as oscillation, are ubiquitous in biology. In this mini review, we present a general summary of the ∼24 h circadian clock and provide a fundamental overview of another biological timekeeper that maintains ∼12 h oscillations. This ∼12 h oscillator is proposed to function independently of the circadian clock to regulate ultradian biological rhythms relevant to both protein homeostasis and liver health. Recent studies exploring these ∼12 h rhythms in humans are discussed, followed by our proposal that mammary gland physiology represents a promising area for further research. We conclude by highlighting potential translational applications in ∼12 h ultradian chronobiology.

Insect cytochrome P450 monooxygenases (CYPs) play crucial roles in the metabolic detoxification of insecticides. Ethyl formate and benzothiazole have recently regained popularity as fumigants due to rising resistance to phosphine in the stored-product pests. However, the mechanisms underlying tolerance to these two fumigants in Lasioderma serricorne, a major global insect pest of stored products, remain poorly understood. In this study, two CYP genes, named CYP6SZ3 and CYP6AEL1, were identified from L. serricorne, belonging to the CYP6 family and containing five conserved domains characteristic of CYP proteins. Spatiotemporal expression analysis revealed that both genes were predominantly expressed in the larval stage and showed the highest expression in the foregut. Upon exposure to ethyl formate and benzothiazole, both genes were upregulated, with significantly increased transcription levels following treatment. RNA interference-mediated silencing of CYP6SZ3 and CYP6AEL1 led to increased susceptibility and significantly higher mortality of L. serricorne when exposed to these fumigants. Homology modeling and molecular docking analyses showed stable binding of these fumigants to CYP6SZ3 and CYP6AEL1 proteins, with binding free energies from -26.88 to -94.68 kcal mol^-1. These findings suggest that the induction of CYP6SZ3 and CYP6AEL1 is likely involved in the detoxification of ethyl formate and benzothiazole in L. serricorne.

Background: The Sensory Organization Test condition 5 (SOT5) assesses an astronaut's vestibular function pre-/post-spaceflight but has a ceiling effect and mainly evaluates standing balance, neglecting the challenges of walking during space missions. A Locomotor Sensory Organization Test (LSOT) has been developed, mirroring the SOT concept but tailored to assess vestibular function during walking. This study aims to advance current knowledge by examining changes in ground reaction force (GRF) during normal walking (LSOT1) and walking in LSOT5 (vision blocked and treadmill speed varied), both with and without mastoid vibrations.

Methods: Sixty healthy adults were recruited and divided into two groups: one with mastoid vibration and one without. GRF peaks and respective variabilities were analyzed in the vertical (V), anterior-posterior (AP), and medial-lateral (ML) directions during stance cycles. The effects of LSOTs and mastoid vibration on each dependent variable were assessed using Friedman's two-way analysis of variance by ranks.

Results: The findings revealed that:1) Walking in LSOT5 increased the variabilities of GRFs regardless of the administration of mastoid vibration; 2) the application of mastoid vibration reduced the amplitude of GRF peaks; and 3) walking in LSOT5 while receiving mastoid vibration was the most challenging task compared to all other tasks in this study.

Conclusion: The results indicated that analyzing GRF can detect changes in the strategy of balance control across different sensory-conflicted conditions. The findings could be beneficial for assessing the vestibular function pre- and post-space missions and planning for future sensorimotor training programs aimed at enhancing astronauts' abilities to navigate unpredictable sensory-conflicted conditions.

Introduction: Current and future astronauts will endure prolonged exposure to spaceflight hazards and environmental stressors that could compromise cognitive functioning, yet cognitive performance in current missions to the International Space Station remains critically under-characterized. We systematically assessed cognitive performance across 10 cognitive domains in astronauts on 6-month missions to the ISS.

Methods: Twenty-five professional astronauts were administered the Cognition Battery as part of National Aeronautics and Space Administration (NASA) Human Research Program Standard Measures Cross-Cutting Project. Cognitive performance data were collected at five mission phases: pre-flight, early flight, late flight, early post-flight, and late post-flight. We calculated speed and accuracy scores, corrected for practice effects, and derived z-scores to represent deviations in cognitive performance across mission phases from the sample's mean baseline (i.e., pre-flight) performance. Linear mixed models with random subject intercepts and pairwise comparisons examined the relationships between mission phase and cognitive performance.

Results: Cognitive performance was generally stable over time with some differences observed across mission phases for specific subtests. There was slowed performance observed in early flight on tasks of processing speed, visual working memory, and sustained attention. We observed a decrease in risk-taking propensity during late flight and post-flight mission phases. Beyond examining group differences, we inspected scores that represented a significant shift from the sample's mean baseline score, revealing that 11.8% of all flight and post-flight scores were at or below 1.5 standard deviations below the sample's baseline mean. Finally, exploratory analyses yielded no clear pattern of associations between cognitive performance and either sleep or ratings of alertness.

Conclusion: There was no evidence for a systematic decline in cognitive performance for astronauts on a 6-month missions to the ISS. Some differences were observed for specific subtests at specific mission phases, suggesting that processing speed, visual working memory, sustained attention, and risk-taking propensity may be the cognitive domains most susceptible to change in Low Earth Orbit for high performing, professional astronauts. We provide descriptive statistics of pre-flight cognitive performance from 25 astronauts, the largest published preliminary normative database of its kind to date, to help identify significant performance decrements in future samples.

Introduction: Cardiorespiratory fitness (CRF), as assessed by VO₂peak, along with metabolic and cardiovascular health indices, represents the strongest predictors of survival. However, it remains unclear whether concurrent high-intensity interval training (HIIT) and resistance training (RT) can similarly enhance these health markers in patients with type-1 diabetes (T1D) or type-2 diabetes (T2D) compared to healthy individuals.

Methods: Adults with uncomplicated T1D or T2D and healthy normoglycemic controls matched for sex and age (HC1 and HC2) performed 3 training sessions/week of concurrent HIIT and RT for 12 weeks. Pre- and post-intervention assessments included: lipids and glycemic profile, body composition (dual-energy x-ray absorptiometry) and a cyclo-ergometric cardio-pulmonary exercise test.

Results: Training improved VO₂peak, the ventilatory threshold (VT1), maximal workload, ventilation and O₂pulse, similarly in T1D in HC1 without changes in body composition or glycemic profile. In patients with T2D, training improved insulin sensitivity (HOMA-IR), lean mass, VE/VCO2 slope, VT1 and maximal O₂pulse, workload and VO₂peak with reduction in fat mass and visceral adipose tissue (VAT) (all, p < 0.05). However, improvements in VO₂peak and O₂pulse were lower than in healthy controls (respectively, T2D: +9%, HC2: +18% and T2D: +6%, HC2: +19%, p < 0.05).

Conclusions: Both patients with T1D and T2D benefit from combined HIIT and RT by improving CRF with specific adaptations influenced by the presence and type of diabetes. While identical magnitude of achievements were observed in T1D and HC1, T2D patients exhibited lower VO₂peak and maximal O₂pulse improvements but associated with notable additional health benefits regarding insulin sensitivity, body composition, visceral adipose tissue and ventilatory efficiency.

Atherosclerosis is a major contributor to cardiovascular diseases and mortality globally. The progression of atherosclerotic disease results in the expansion of plaques and the development of necrotic cores. Subsequent plaque rupture can lead to thrombosis, occluding blood vessels, and end-organ ischemia with consequential ischemic injury. Atherosclerotic plaques are formed by the accumulation of lipid particles overloaded in the subendothelial layer of blood vessels. Abnormally elevated blood lipid levels and impaired endothelial function are the initial factors leading to atherosclerosis. The atherosclerosis research has never been interrupted, and the previous view was that the pathogenesis of atherosclerosis is an irreversible and chronic process. However, recent studies have found that the progression of atherosclerosis can be halted when patients' blood lipid levels are reversed to normal or lower. A large number of studies indicates that it can inhibit the progression of atherosclerosis lesions and promote the regression of atherosclerotic plaques and necrotic cores by lowering blood lipid levels, improving the repair ability of vascular endothelial cells, promoting the reverse cholesterol transport in plaque foam cells and enhancing the ability of macrophages to phagocytize and clear the necrotic core of plaque. This article reviews the progress of research on the mechanism of atherosclerotic plaque regression. Our goal is to provide guidance for developing better therapeutic approaches to atherosclerosis by reviewing and analyzing the latest scientific findings.

Introduction: The human voice is generated by the oscillation of the vocal folds induced by exhalation airflow. Consequently, the characteristics of these oscillations and the primary sound signal are controlled by the longitudinal tension of the vocal folds, the flow rate, and their prephonatoric position. To facilitate independent control of these parameters, a synthetic larynx model was developed, as detailed in a previous publication.

Methods: This study aims to statistically analyze the influence of airflow and fiber tension on phonation characteristics, such as periodicity and symmetry, glottis closure during vocal fold oscillations, as well as tissue elasticity and generated sound. A total of 76 experiments were conducted and statistically analyzed with a systematic variation of flow rate and longitudinal tension within the vocal folds.During these experiments, vocal fold motion, subglottal pressure, and emitted sound were meticulously measured and analyzed.

Results: Groupwise statistical testing identified the flow rate as the main influencing parameter on nearly all phonation characteristics. However, the fundamental frequency, stiffness parameters, and quality parameters of the primary sound signal are predominantly controlled by the longitudinal tension within the vocal folds.

Discussion: The results demonstrated a complex interplay between the flow rate and tension, resulting in different characteristics of the produced sound signal.

K2 performance depends on different kinematic and kinetic variables. Due to the lack of related studies in this area, we have tried to explain these features to better understand the best positioning of paddlers and how their synchronization affects performance. This study uses the DAQ system comprising two instrumented paddles-an IMU and a GPS ("E-kayak" system)-to investigate paddle synchronization and the specific positioning of paddlers' in preferred and inverted configurations. In this study, 10 sub-elite paddlers participated, divided into five crews. The test included two trials of 500 m performed in preferred and inverted seating positions. The synchronization analysis highlighted that the rear paddler contributed efficiently to the propulsion of the boat while performing 30-40 ms earlier than the front paddler during the entry and exit phases. Despite the time results for 500 m, there is no evidence indicating a dominant indication of the preferred or inverted position among the athletes. The results show a significant correlation (p < 0.05) between the force of the front paddler (r = -0.88), the stroke frequency of the crew (r = -0.66), and the total force applied by the crew with the time for 500 m and between stroke frequency and the force of the front paddler (r = 0.64). Based on these indications, for only those crews who completed the 500 m test in the shortest time, the equation determining the time over 500 m was calculated using multiple regression analysis, considering the stroke frequency and the force of the front and rear paddler. The data showed a good estimation with CV% = 0.22, ICC = 0.99, and ES = -0.005. In conclusion, these findings can serve as a beneficial tool for assessing or monitoring K2 crew performance in sub-elite paddlers.