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In this research, a chronoamperometric biosensor based on zinc oxide (ZnO)-graphene oxide (GO) nanocomposite material was designed and employed for lactate determination. The ZnO-GO hybrid proved to be a suitable substrate for the immobilization of lactate oxidase (LOD). The presence of ZnO and GO components in hybrid material led to synergistic effects and facilitates the LOD loading and electron transfer between the receptor and screen printed carbon electrode (SPCE) surface. The LOD-GO-ZnO modified SCPE exhibits excellent lactate sensing capabilities thanks to the uniform dispersion of ultrafine ZnO nanoparticles and enhanced mass-transfer kinetics. In phosphate buffer solution (pH=7.4), this novel electrochemical lactate biosensor demonstrates a linear response to lactate within the concentration range of 0.015–1.25 mM. Limit of detection (based on S/N=3) of the assay was estimated to be 9 µM. More importantly, the presence method is a highly selective device for the analysis of lactate in biological fluids. The lactate level in saliva samples was successfully measured before and after exercise of athletes using the suggested biosensor. This method offers a simple, cost-effective, fast, and effective platform for lactate determination in typical diagnostic applications.

Objective: To evaluate the antiobesity effect and underlying mechanism of Andrias davidianus peptide (ADP) supplementation combined with treadmill exercise. Methods: A mouse model of obesity was established by feeding mice a high-fat diet (HFD), and the obese mice were randomly divided into four groups: model, treadmill exercise (Ex), ADP and ADP combined with treadmill exercise (ADP + Ex). The rats in the Ex group were subjected to a six-week treadmill exercise training. The rates in the ADP group were gavaged with ADP for six weeks. The rats in the ADP + Ex group were treated with ADP supplementation combined with treadmill exercise training. Normal Sprague Dawley (SD) rats were used as the control (CN) group. Body mass and food intake were recorded each week, and the serum levels of glucagon-like peptide-1 (GLP-1), neuropeptide Y (NPY), irisin, leptin, triglycerides (TG), total cholesterol (TC), low density lipoprotein (LDL) and high density lipoprotein (HDL) were investigated by enzyme-linked immunosorbent assay (ELISA). Western blot was used to detect the expression of appetite-regulated proteins (NPY and proopiomelanocortin (POMC)) and energy metabolism-related proteins. Results: Body mass, inguinal and epididymal fat accumulation, food intake, and serum TG, TC and LDL levels significantly decreased in the ADP + Ex group compared with the model group. In addition, ELISA results revealed that combination of ADP supplementation with treadmill exercise reduced the serum levels of NPY and leptin but increased the serum concentrations of GLP-1 and irisin in obese rats. Western blot analysis showed that ADP supplementation combined with treadmill exercise greatly up-regulated the expression of POMC and energy metabolism related proteins (irisin, phospho-adenosine monophosphate-activated protein kinase, peroxisome proliferator-activated receptor γ co-activated factor-1α, and fibronectin type III domain containing protein 5), but down-regulated the expression of NPY. Conclusion: The combination of ADP with aerobic exercise can effectively alleviate HFD-induced obesity, thereby providing a new promising strategy to alleviate HFD-induced obesity.

Myocardial fibrosis can trigger heart failure in diabetic cardiomyopathy (DCM), and irisin, an exercise-induced myokine, may have a beneficial effect on cardiac function. However, the specific molecular mechanism between exercise and irisin in the diabetic heart remains not fully explored. This study aimed to investigate how miR-34a mediates exercise-induced irisin to ameliorate myocardial fibrosis and its underlying mechanisms. Type 2 diabetes mellitus (T2DM) with DCM was induced in adult male rats with high-fat diet and streptozotocin injection. The DCM rats were subjected to swimming (60 min/d) and recombinant irisin (r-irisin, 500 μg/kg/d) interventions for 8 weeks, respectively. Cardiac function, cardiomyocyte structure, myocardial fibrosis and its correlated gene and protein expression were analyzed. Swimming intervention alleviated insulin resistance, myocardial fibrosis, and myocardial hypertrophy, and promoted blood glucose homeostasis in T2DM model rats. This improvement was associated with irisin upregulation and miR-34a downregulation in the myocardium, thus enhancing cardiac function. Similar efficacy was observed via intraperitoneal injection of exogenous recombinant irisin. Inhibition of miR-34a in vivo exhibited an anti-myocardial fibrotic effect by promoting irisin secretion through activating sirtuin 1 (SIRT1)/peroxisome proliferator-activated receptor-gamma coactivator-1α (PGC-1α)/fibronectin type III domain-containing protein 5 (FNDC5) signal pathway and downregulating myocardial fibrosis markers (collagen I, collagen III, and transforming growth factor-β1). Therefore, swimming-induced irisin has the potential therapeutic effect on diabetic myocardial fibrosis through activating the miR-34a-mediated SIRT1/PGC-1α/FNDC5 signal pathway. [ABSTRACT FROM AUTHOR]

With the increasingly severe situation of obesity and population aging, there is growing concern about sarcopenia obesity (SO). SO refers to the coexistence of obesity and sarcopenia, which imposes a heavier burden on individuals and society compared to obesity or sarcopenia alone. Therefore, comprehending the pathogenesis of SO and implementing effective clinical interventions are vital for its prevention and treatment. This review uses a comprehensive literature search and analysis of PubMed, Web of Science, and CNKI databases, with search terms including "Sarcopenic obesity", "exercise", "cytokines", "inflammation", "mitochondrial quality control", and "microRNA", covering relevant studies published up to July 2024. The results indicate that the pathogenesis of SO is complex, involving mechanisms like age-related changes in body composition, hormonal alterations, inflammation, mitochondrial dysfunction, and genetic and epigenetic factors. Regarding exercise interventions for SO, aerobic exercise can reduce fat mass, resistance exercise can increase skeletal muscle mass and strength, and combined exercise can achieve both, making it the optimal intervention for SO. The potential mechanisms by which exercise may prevent and treat SO include regulating cytokine secretion, inhibiting inflammatory pathways, improving mitochondrial quality, and mediating microRNA expression. This review emphasizes the effectiveness of exercise interventions in mitigating sarcopenic obesity through comprehensive analysis of its multifactorial pathogenesis and the mechanistic insights into exercise's therapeutic effects. Understanding these mechanisms informs targeted therapeutic strategies aimed at alleviating the societal and individual burdens associated with SO. [ABSTRACT FROM AUTHOR]

Background: After anterior cruciate ligament reconstruction (ACLR), single-leg horizontal hop distance limb symmetry index (LSI) >90% is recommended as a cutoff point for safe return to sport (RTS). However, athletes after ACLR have abnormal lower limb biomechanics despite an adequate single-leg hop distance LSI, implying that athletes are at high risk of reinjury. Symmetry of single-leg vertical jump height appears to be more difficult to achieve and can be a better representation of knee function than single-leg horizontal hop distance. Hypothesis: Athletes after ACLR with single-leg jump height LSI >90% had similar biomechanical characteristics to healthy athletes. Study Design: Controlled laboratory study. Level of Evidence: Level 3. Methods: A total of 46 athletes after ACLR were divided into low jump height (LJH, jump height LSI <90%, n = 23) and high jump height (HJH, jump height LSI >90%, n = 23) groups according to symmetry of single-leg vertical jump height, while 24 healthy athletes acted as a control (CONT) group. One-way analysis of variance was used to compare the kinematic and kinetic characteristics of the LJH, HJH, and CONT groups during single-leg vertical jump. Results: Both the LJH and HJH groups demonstrated greater limb asymmetry (lower LSI) during landing compared with the CONT group in knee extension moment (P < 0.05), peak knee flexion angle (P < 0.05), and knee power (P < 0.05). Conclusion: Symmetry in single-leg vertical jump height does not represent normal lower limb biomechanics in athletes after ACLR. Clinical Relevance: Symmetrical jump height may not signify ideal biomechanical or RTS readiness, but single-leg vertical jump test can be used as a supplement to horizontal hop test or other functional tests to reduce the likelihood of false-negative results in the absence of detailed biomechanical evaluation. [ABSTRACT FROM AUTHOR]

The Shuangwang Au deposit (with a gold resource of approximately 70 t Au), is located in the Fenxian-Taibai fore-arc basin in the West Qinling Orogen of central China. Igneous intrusions in the region include the Xiba granitic pluton and granite porphyry and lamprophyre dykes. The Xiba pluton is composed of granodiorite and monzonite granite. The granodiorite is typical I-type granite, and it yields a crystallization age of 221.1 ± 1.2 Ma and a two-stage Hf model age of 1432–1634 Ma. The monzonite granite shows a transitional characteristic between I-type and A-type granite, and it yields a crystallization age of 214.8 ± 1.2 Ma and a two-stage Hf model age of 1443–1549 Ma. The granitoid was derived mainly from a crust–mantle mixed source. The ages indicate that the granodiorite and monzonite granite formed during two different stages. The REE distribution patterns of the Xiba granitoid exhibit significant fractionation between LREE and HREE, showing right-dipping curves, with an enrichment of LREE and a deficit of HREE. The granodiorite displays a light negative Eu anomaly, while the monzonite granite displays an obvious negative Eu anomaly. The granite porphyry dikes are distributed in the No. I breccia and Jiupinggou granite porphyry, and they yield crystallization ages of 219.9 ± 1.5 Ma and 213.1 ± 0.89 Ma, respectively, and two-stage Hf model ages of 1382–1501 Ma and 1373–1522 Ma, respectively. The lamprophyre dikes in the deposit yield a crystallization age of 214.4 ± 2.7 Ma. After the collision event between the Yangtze and the North China Plates along the Qinling orogenic belt, at approximately 220 Ma in the Late Triassic, the detachment of the slab produced the upwelling of the asthenosphere material. Under conditions of mantle heat and tectonic stress, widespread partial melting of the subducted continental crust and the upper lithosphere mantle occurred, forming granitoids with various degrees of adakite characteristics. [ABSTRACT FROM AUTHOR]

Introduction: We investigated the effects of electroacupuncture (EA) on improving obesity and insulin resistance (IR) in high-fat diet-induced (HFDI) obese rats by modulating the nucleus tractus solitarius (NTS) glucagon-like peptide-1 (GLP-1)-ventral tegmental area (VTA) dopamine (DA) neural reward circuit, thereby uncovering a possible central mechanism underlying EA's actions in improving obesity and IR. Methods: We randomly allocated 45 Wistar male rats to five groups (normal, model, EA, chemogenetic activation, chemogenetic suppression + EA), with 9 rats in each group. All interventions were conducted within 8 weeks after the model was established. We tested rats for obesity phenotypes included body mass, Lee's index, 24-h food intake, and glucose-metabolism parameters. We observed protein and gene expression for GLP-1 in the NTS and tyrosine hydroxylase in the VTA by Western blotting and real-time polymerase chain reaction, as well as their localization by immunofluorescence. We also determined the DA content in the VTA using high-performance liquid chromatography. Results: Obese rats exhibited marked hyperphagia, accompanied by increased excitability of DA neurons in the VTA region and reduced insulin sensitivity. After EA treatment, obese rats showed augmented excitability of NTS GLP-1 and suppression of VTADA neurons with a diminution in food intake, showing results similar to those in the chemogenetic activation group. After EA treatment and while inhibiting GLP-1 neurons by chemogenetics, the effect of EA on activating GLP-1 neurons and inhibiting VTADA was partially abrogated. The effects of improving obesity and insulin sensitivity were likewise also suppressed. Conclusion: EA effectively activated GLP-1 neurons in the NTS, thereby inhibited the expression of DA in the VTA and improved obesity and insulin sensitivity in HFDI-obese rats. [ABSTRACT FROM AUTHOR]

Purpose: The current biomechanical research on the application of Kinesio taping (KT) to patients with chronic ankle instability (CAI) has focused on testing the expected movements. However, unexpected movements are more common in actual sports. Therefore, the present study aimed to investigate the effects of KT on the biomechanical characteristics of the knee and ankle joints during unexpected jumping movements. Methods: Twenty‐one patients with unilateral CAI were recruited to capture the biomechanical parameters during unexpected jumping movements under different interventions: no taping (NT), placebo taping (PT), and KT. A one‐way repeated measures analysis of variance was used to compare the differences in knee and ankle biomechanical characteristics among patients with CAI between the three intervention conditions. Results: At initial contact, the KT group demonstrated a significant decrease in ankle plantarflexion and knee flexion angles compared to the NT group (p < 0.05). At the early landing phase, the KT group had a significant increase in peak ankle dorsiflexion angle, peak ankle eversion angle, peak ankle dorsiflexion moment, and peak ankle eversion moment compared to the NT and PT groups (p < 0.05). Furthermore, the KT group had a significantly reduced peak knee flexion angle, peak knee eversion angle, and peak vertical ground reaction force (p < 0.05) compared to the NT and PT groups. Conclusion: KT significantly improves the sprain‐prone touchdown posture of patients with CAI. And reducing the risk of ankle sprains during the early landing phase by promoting ankle dorsiflexion and eversion angles and moments. [ABSTRACT FROM AUTHOR]

Background: Various muscle contraction modalities have differing effects on the musculoskeletal system. To understand the magnitude of these effects, the authors investigated the effects of eccentric and concentric contractions on the bone-tendon interface after rotator cuff repair in mice. Hypothesis: Eccentric contraction promotes healing of the bone-tendon interface after rotator cuff repair in mice better than other muscle contraction patterns. Study Design: Controlled laboratory study. Methods: The authors performed acute supraspinatus tendon repair of the right shoulder in 104 C57BL/6 mice. Animals were randomized into 4 groups postoperatively: control group (Con group), horizontal running group (Horz group), +15° uphill running group (Up group), and −15° downhill running group (Down group), with 26 animals in each group. At 4 and 8 weeks postoperatively, the authors removed the eyeball, collected blood samples, and extracted the supraspinatus tendon–humerus complex for histological, immunological, bone morphological, and biomechanical tests. Results: At 4 and 8 weeks postoperatively, the Down group exhibited a better collagen cell arrangement and fibrocartilage layer than the other 3 groups. At 4 weeks postoperatively, anti-inflammatory macrophages (M2 macrophages) were observed at the repair site in all groups except for the Con group. At 8 weeks postoperatively, M2 macrophages were withdrawn from the tendon site in all groups. The transforming growth factor β1 concentration in the Down group was greater than that in the other 3 groups at 4 weeks postoperatively, and it was higher than that in the Con group at 8 weeks postoperatively. The bone volume fraction, number of trabeculae, and thickness of trabeculae at the repair site in the Down group, as well as the ultimate strength and failure load in the biomechanical tests, were greater than those in the other 3 groups at 8 weeks postoperatively. Conclusion: Eccentric contraction promotes healing of the bone-tendon interface after rotator cuff repair in mice better than other muscle contraction patterns. Clinical Relevance: After clinical rotator cuff repair, patients can be rehabilitated by eccentric training to speed up the functional recovery of the shoulder joint. [ABSTRACT FROM AUTHOR]