Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

ObjectiveTo explore the role and potential mechanism of circulating glutamate in enhancing insulin sensitivity by aerobic exercise. This research may provide a novel strategy for preventing metabolic diseases through precise exercise interventions. MethodsTo investigate the effects of elevated circulating glutamate on insulin sensitivity and its potential mechanisms, 18 male C57BL/6 mice aged 6 to 8 weeks were randomly divided into 3 groups: a control group (C), a group receiving 500 mg/kg glutamate supplementation (M), and a group receiving 1 000 mg/kg glutamate supplementation (H). The intervention lasted for 12 weeks, with treatments administered 6 d per week. Following the intervention, an insulin tolerance test (ITT) and a glucose tolerance test (GTT) were conducted. Circulating glutamate levels were measured using a commercial kit, and the activity of the skeletal muscle InsR/IRS1/PI3K/AKT signaling pathway was analyzed via Western blot. To further investigate the role of circulating glutamate in enhancing insulin sensitivity through aerobic exercise, 30 male C57BL/6 mice were randomly assigned to 3 groups: a control group (CS), an exercise intervention group (ES), and an exercise combined with glutamate supplementation group (EG). The ES group underwent treadmill-based aerobic exercise, while the EG group received glutamate supplementation at a dosage of 1 000 mg/kg in addition to aerobic exercise. The intervention lasted for 10 weeks, with sessions occurring 6 d per week, and the same procedures were followed afterward. To further elucidate the mechanism by which glutamate modulates the InsR/IRS1/PI3K/AKT signaling pathway, C2C12 myotubes were initially subjected to graded glutamate treatment (0, 0.5, 1, 3, 5, 10 mmol/L) to determine the optimal concentration for cellular intervention. Subsequently, the cells were divided into 3 groups: a control group (C), a glutamate intervention group (G), and a glutamate combined with MK801 (an NMDA receptor antagonist) intervention group (GK). The G group was treated with 5 mmol/L glutamate, while the GK group received 50 μmol/L MK801 in addition to 5 mmol/L glutamate. After 24 h of intervention, the activity of the InsR/IRS1/PI3K/AKT signaling pathway was analyzed using Western blot. ResultsCompared to the mice in group C, the circulating glutamate levels, the area under curve (AUC) of ITT, and the AUC of GTT in the mice of group H were significantly increased. Additionally, the expression levels of p-InsRβ, IRS1, p-AKT, and p-mTOR proteins in skeletal muscle were significantly downregulated. Compared to the mice in group CS, the circulating glutamate levels, the AUC of ITT, and the AUC of GTT in the mice of group ES were significantly reduced. Additionally, the expression levels of p-InsRβ, IRS1, p-AKT, and p-mTOR proteins in skeletal muscle of group ES mice were significantly upregulated. There were no significant changes observed in the mice of group EG. Compared to the cells in group 0 mmol/L, the expression levels of p-InsRβ, p-IRS1, p-PI3K, and p-AKT proteins in cells of group 5 mmol/L were significantly downregulated. Compared to the cells in group C, the expression levels of p-InsRβ, p-IRS1, p-PI3K, and p-AKT proteins in the cells of group G were significantly downregulated. No significant changes were observed in the cells of group GK. ConclusionLong-term aerobic exercise can improve insulin sensitivity by lowering circulating levels of glutamate. This effect may be associated with the upregulation of the InsR/IRS1/AKT signaling pathway activity in skeletal muscle. Furthermore, glutamate can weaken the activity of the InsR/IRS1/PI3K/AKT signaling pathway in skeletal muscle, potentially by binding to NMDAR expressed in skeletal muscle.

ObjectiveThe primary objective of this study was to investigate the effects of carbohydrate intake order on post-exercise recovery and metabolic regulation under heat stress, particularly in models of exercise induced fatigue. Given the increasing significance of optimizing nutritional strategies to support performance in extreme environmental conditions, this study aimed to provide experimental evidence that contributes to a better understanding of how the sequence in which carbohydrates are consumed impacts exercise recovery, metabolic homeostasis, and fatigue alleviation in a high-temperature environment. MethodsA mouse model of exercise-induced fatigue was established under high-temperature (35°C) to simulate heat stress. The subjects were divided into 3 distinct groups based on their carbohydrate intake order: the “mixed intake” group (HOT_MIX), where all macronutrients (carbohydrates, proteins, and fats) were consumed in a balanced ratio; the “carbohydrate-first intake” group (HOT_CHO), where carbohydrates were consumed first followed by other macronutrients; the “carbohydrate-later intake” group (HOT_PRO), where proteins and fats were consumed prior to carbohydrates. Each group underwent a 7 d intervention period with daily intake according to their designated group. Exercise performance was assessed using rotarod retention time test, and biomarkers of muscle damage, such as lactate dehydrogenase (LDH), creatine kinase (CK), lactate (LD), alanine aminotransferase (ALT), and non-esterified fatty acids (NEFA), were measured. Furthermore, targeted metabolomics analyses were conducted to investigate metabolic shifts in response to different dietary strategies, and KEGG pathway enrichment analysis was employed to explore the biological mechanisms underlying these changes. ResultsThe findings demonstrated that the HOT_PRO group exhibited a significantly improved performance in the rotarod test, with a longer retention time compared to both the HOT_MIX and HOT_CHO groups (P<0.05). Additionally, this group showed significantly reduced levels of muscle damage markers such as LDH and CK, indicating that the carbohydrate-later intake strategy helped alleviate exercise-induced muscle injury. Metabolomic profiling of the HOT_PRO group showed marked increases in alanine, creatine, and flavin adenine dinucleotide (FAD), indicating shifts in amino acid metabolism and oxidative metabolism. Conversely, metabolites such as spermidine, cholesterol sulfate, cholesterol, and serine were significantly reduced in the HOT_PRO group, pointing to alterations in lipid and sterol metabolism. Further analysis of the differential metabolites revealed that these changes were primarily associated with key metabolic pathways, including glycine-serine-threonine metabolism, primary bile acid biosynthesis, taurine and hypotaurine metabolism, and steroid hormone biosynthesis. These pathways are essential for energy production, antioxidant defense, and muscle recovery, suggesting that the carbohydrate-later feeding strategy may promote metabolic homeostasis and improve exercise recovery by enhancing these critical metabolic processes. ConclusionThe results of this study support the hypothesis that consuming carbohydrates after proteins and fats during exercise recovery enhances metabolic homeostasis and accelerates recovery under heat stress. This strategy effectively modulates energy, amino acid, and lipid-related pathways, which are crucial for improving endurance performance and mitigating fatigue in high-temperature environments. The findings suggest that carbohydrate-later intake could be a promising nutritional strategy for athletes and individuals exposed to heat during physical activity. Furthermore, the study provides valuable insights into how different nutrient timing strategies can impact exercise recovery and metabolic regulation, paving the way for more personalized and effective nutritional interventions in extreme environmental conditions.

This paper aimed to systematically evaluate the effects of hypoxic training at different fraction of inspired oxygen (FiO₂) on body composition, glucose metabolism, and lipid metabolism in obese individuals, and to determine the optimal oxygen concentration range to provide scientific evidence for personalized and precise hypoxic exercise prescriptions. A systematic search was conducted in the Cochrane Library, PubMed, Web of Science, Embase, and CNKI databases for randomized controlled trials and pre-post intervention studies published up to March 31, 2025, involving hypoxic training interventions in obese populations. Meta-analysis was performed using RevMan 5.4 software to assess the effects of different fraction of inspired oxygen (FiO₂≤14% vs. FiO₂>14%) on BMI, body fat percentage, waist circumference, fasting blood glucose, insulin, HOMA-IR, triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C), with subgroup analyses based on oxygen concentration. A total of 22 studies involving 292 participants were included. Meta-analysis showed that hypoxic training significantly reduced BMI (mean difference (MD)=-2.29,95%CI: -3.42 to -1.17, P<0.000 1), body fat percentage (MD=-2.32, 95%CI: -3.16 to -1.47, P<0.001), waist circumference (MD=-3.79, 95%CI: -6.73 to -0.85, P=0.01), fasting blood glucose (MD=-3.58, 95%CI: -6.23 to -0.93, P=0.008), insulin (MD=-1.60, 95%CI: -2.98 to -0.22, P=0.02), TG (MD=-0.18, 95%CI: -0.25 to -0.12, P<0.001), and LDL-C (MD=-0.25, 95%CI: -0.39 to -0.11, P=0.000 3). Greater improvements were observed under moderate hypoxic conditions with FiO₂>14%. Changes in HOMA-IR (MD=-0.74, 95%CI: -1.52 to 0.04,P=0.06) and HDL-C (MD=-0.09, 95%CI: -0.21 to 0.02, P=0.11) were not statistically significant. Hypoxic training can significantly improve body composition, glucose metabolism, and lipid metabolism indicators in obese individuals, with greater benefits observed under moderate hypoxia (FiO>14%). As a key parameter in hypoxic exercise interventions, the precise setting of oxygen concentration is crucial for optimizing intervention outcomes.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Cardiovascular diseases are the leading cause of mortality, posing a significant threat to human health due to the high incidence rate. Atherosclerosis, a chronic inflammatory disease, serves as the primary pathological basis for most such conditions. The incidence of atherosclerosis continues to rise, but its pathogenesis has not been fully elucidated. As an important member of the small GTPase superfamily, Ras-association proximate 1 (Rap1) is an important molecular switch involved in the regulation of multiple physiological functions including cell differentiation, proliferation, and adhesion. Rap1 achieves the utility of the molecular switch by cycling between Rap1-GTP and Rap1-GDP. Rap1 may influence the occurrence and development of atherosclerosis in a cell-specific manner. This article summarizes the potential role and mechanism of Rap1 in the progression of atherosclerosis in different cells, aiming to provide new therapeutic targets and strategies for clinical intervention.
Humans ; Atherosclerosis/metabolism* ; rap1 GTP-Binding Proteins/physiology* ; Animals ; Cell Differentiation ; Cell Adhesion ; Cell Proliferation

The circadian clock plays a critical role in regulating various physiological processes, including gene expression, metabolic regulation, immune response, and the sleep-wake cycle in living organisms. Post-translational modifications (PTMs) are crucial regulatory mechanisms to maintain the precise oscillation of the circadian clock. By modulating the stability, activity, cell localization and protein-protein interactions of core clock proteins, PTMs enable these proteins to respond dynamically to environmental and intracellular changes, thereby sustaining the periodic oscillations of the circadian clock. Different types of PTMs exert their effects through distincting molecular mechanisms, collectively ensuring the proper function of the circadian system. This review systematically summarized several major types of PTMs, including phosphorylation, acetylation, ubiquitination, SUMOylation and oxidative modification, and overviewed their roles in regulating the core clock proteins and the associated pathways, with the goals of providing a theoretical foundation for the deeper understanding of clock mechanisms and the treatment of diseases associated with circadian disruption.
Protein Processing, Post-Translational/physiology* ; Circadian Rhythm/physiology* ; Humans ; Animals ; CLOCK Proteins/physiology* ; Circadian Clocks/physiology* ; Phosphorylation ; Acetylation ; Ubiquitination ; Sumoylation

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.

Objective: To evaluate the feasibility of dynamic contrast-enhanced MRI (DCE-MRI) in differentiating tumor deposits (TDs) from metastatic lymph nodes (MLNs) in rectal cancer. Materials and Methods: A retrospective analysis was conducted on 70 patients with rectal cancer, including 168 lesions (70 TDs and 98 MLNs confirmed by histopathology), who underwent pretreatment MRI and subsequent surgery between March 2019 and December 2022. The morphological characteristics of TDs and MLNs, along with quantitative parameters derived from DCE-MRI (K trans , kep, and v e) and DWI (ADCmin, ADCmax, and ADCmean), were analyzed and compared between the two groups.Multivariable binary logistic regression and receiver operating characteristic (ROC) curve analyses were performed to assess the diagnostic performance of significant individual quantitative parameters and combined parameters in distinguishing TDs from MLNs. Results: All morphological features, including size, shape, border, and signal intensity, as well as all DCE-MRI parameters showed significant differences between TDs and MLNs (all P < 0.05). However, ADC values did not demonstrate significant differences (all P > 0.05). Among the single quantitative parameters, v e had the highest diagnostic accuracy, with an area under the ROC curve (AUC) of 0.772 for distinguishing TDs from MLNs. A multivariable logistic regression model incorporating short axis, border, v e, and ADC mean improved diagnostic performance, achieving an AUC of 0.833 (P = 0.027). Conclusion The combination of morphological features, DCE-MRI parameters, and ADC values can effectively aid in the preoperative differentiation of TDs from MLNs in rectal cancer.