BACKGROUND:Muscle aging is closely related to various epigenetic changes,and exercise has a certain regulatory effect on these epigenetic changes.However,the specific mechanism is not fully understood. OBJECTIVE:To review the epigenetic mechanisms of skeletal muscle and how exercise can improve skeletal muscle aging and promote adaptive changes in muscle through these epigenetic mechanisms,aiming to provide a more comprehensive understanding of skeletal muscle aging and disease mechanisms. METHODS:During the period from June 1st to August 1st,2023,literature searches were conducted for relevant literature published from database inception to August 2023 in databases including Web of Science,PubMed,CNKI,WanFang,and VIP.The search terms used included"skeletal muscle,""muscle,""aging,""older adult,""aging,""exercise,""physical exercise,""epigenetic,"and"epigenetics"in Chinese as well as"skeletal muscle,muscle,aging,older adult,senescence,age,exercise,sports,physical activity,epigenetic,epigenetics"in English.Boolean logic operators were used to connect the search terms for retrieval,and corresponding strategies were developed.According to the predetermined inclusion and exclusion criteria,70 eligible articles were selected. RESULTS AND CONCLUSION:Epigenetics refers to the phenomenon where gene expression and function are regulated without changes in gene sequence,and epigenetic changes in skeletal muscle are an important field.The epigenetic mechanisms of skeletal muscle play an important role in muscle aging,mainly involving DNA methylation,histone modification,regulation of non-coding RNAs,chromatin remodeling,changes in mitochondrial function and expression changes of aging-related genes.Exercise significantly regulates the epigenetics of skeletal muscle,including promoting DNA methylation,muscle histone modification,regulating miRNA expression,and regulating lncRNA expression,regulating muscle factors(such as interleukin-6),regulating mitochondrial function(such as peroxisome proliferators-activated receptors γ co-activator 1α).Future studies are recommended for long-term,cross-diverse population-based exercise interventions;the application of multi-omics techniques such as proteomics and metabolomics;strengthening the understanding of epigenetic changes at the single-cell level;cross-species comparative studies as well as human clinical trials for the translation of animal model findings to humans;strategies for combining exercise and pharmacological interventions to assess their synergistic effects;and epigenetic studies of crosstalk interactions between skeletal muscle and different organs.

BACKGROUND:Individuals with chronic ankle instability are prone to inversion ankle sprains during landing.Moderately increasing the foot toe-out angle during landing may reduce the occurrence of inversion ankle sprains,but no studies have directly demonstrated this effect. OBJECTIVE:To explore the effect of increased toe-out angle during landing on the peak inversion angle,peak angular velocity,and the time to peak inversion among individuals with and without chronic ankle instability. METHODS:A total of 60 participants were recruited for this study,including 30 individuals with chronic ankle instability and 30 without chronic ankle instability.The study utilized a simulated sprain apparatus for drop-landing tests,featuring a platform that could tilt forward by 24° and inward by 15°,thus simulating the foot position during an ankle inversion sprain.Participants were required to perform drop-landing tests under two landing conditions:natural landing and toe-out landing,with the latter involving a greater foot toe-out angle,over 150%more than the former.Kinematic data of participants were recorded using a 12-camera three-dimensional motion capture system.Data analysis was conducted using two-way repeated measures analysis of variance and Spearman correlation analysis. RESULTS AND CONCLUSION:(1)Significant main effects of condition were found for peak inversion angle during drop-landing(P<0.001,η2 p=0.270),peak inversion velocity(P=0.015,η2 p=0.098),and peak inversion time(P<0.001,η2 p=0.260);a significant main effect of group was found for peak inversion velocity(P=0.029,η2 p=0.080).(2)There were significant negative correlations between the foot toe-out angle at landing and the peak ankle inversion angle(P=0.021,r=-0.310;P=0.042,r=-0.278)as well as the peak inversion time(P=0.018,r=-0.312;P=0.021,r=-0.309)in both chronic ankle instability and non-chronic ankle instability groups.Moreover,a significant negative correlation was also found between the foot toe-out angle and peak inversion velocity in the chronic ankle instability group(P=0.021,r=-0.312).(3)It is indicated that increasing the foot toe-out angle at landing can reduce the peak inversion angle,peak inversion velocity,and the peak inversion time during landing in patients with chronic ankle instability and non-chronic ankle instability,thereby decreasing the risk of ankle inversion sprains.

Debates persist regarding the efficacy and safety of azvudine, particularly its real-world outcomes. This study involved patients aged ≥60 years who were admitted to 25 hospitals in mainland China with confirmed SARS-CoV-2 infection between December 1, 2022, and February 28, 2023. Efficacy outcomes were all-cause mortality during hospitalization, the proportion of patients discharged with recovery, time to nucleic acid-negative conversion (T _NANC), time to symptom improvement (T _SI), and time of hospital stay (T _HS). Safety was also assessed. Among the 5884 participants identified, 1999 received azvudine, and 1999 matched controls were included after exclusion and propensity score matching. Azvudine recipients exhibited lower all-cause mortality compared with controls in the overall population (13.3% vs. 17.1%, RR, 0.78; 95% CI, 0.67-0.90; P = 0.001) and in the severe subgroup (25.7% vs. 33.7%; RR, 0.76; 95% CI, 0.66-0.88; P < 0.001). A higher proportion of patients discharged with recovery, and a shorter T _NANC were associated with azvudine recipients, especially in the severe subgroup. The incidence of adverse events in azvudine recipients was comparable to that in the control group (2.3% vs. 1.7%, P = 0.170). In conclusion, azvudine showed efficacy and safety in older patients hospitalized with COVID-19 during the SARS-CoV-2 omicron wave in China.

The current study aimed to clarify the roles of apolipoprotein A5 (ApoA5) and milk fat globule-epidermal growth factor 8 (Mfge8) in regulating myocardial lipid deposition and the regulatory relationship between them. The serum levels of ApoA5 and Mfge8 in obese and healthy people were compared, and the obesity mouse model induced by the high-fat diet (HFD) was established. In addition, primary cardiomyocytes were purified and identified from the hearts of suckling mice. The 0.8 mmol/L sodium palmitate treatment was used to establish the lipid deposition cardiomyocyte model in vitro. ApoA5-overexpressing adenovirus was used to observe its effects on cardiac function and lipids. The expressions of the fatty acid uptake-related molecules and Mfge8 on transcription or translation levels were detected. Co-immunoprecipitation was used to verify the interaction between ApoA5 and Mfge8 proteins. Immunofluorescence was used to observe the co-localization of Mfge8 protein with ApoA5 or lysosome-associated membrane protein 2 (LAMP2). Recombinant rMfge8 was added to cardiomyocytes to investigate the regulatory mechanism of ApoA5 on Mfge8. The results showed that participants in the simple obesity group had a significant decrease in serum ApoA5 levels (P < 0.05) and a significant increase in Mfge8 levels (P < 0.05) in comparison with the healthy control group. The adenovirus treatment successfully overexpressed ApoA5 in HFD-fed obese mice and palmitic acid-induced lipid deposition cardiomyocytes, respectively. ApoA5 reduced the weight of HFD-fed obese mice (P < 0.05), shortened left ventricular isovolumic relaxation time (IVRT), increased left ventricular ejection fraction (LVEF), and significantly reduced plasma levels of triglycerides (TG) and cholesterol (CHOL) (P < 0.05). In myocardial tissue and cardiomyocytes, the overexpression of ApoA5 significantly reduced the deposition of TG (P < 0.05), transcription of fatty acid translocase (FAT/CD36) (P < 0.05), fatty acid-binding protein (FABP) (P < 0.05), and fatty acid transport protein (FATP) (P < 0.05), and protein expression of Mfge8 (P < 0.05), while the transcription levels of Mfge8 were not significantly altered (P > 0.05). In vitro, the Mfge8 protein was captured using ApoA5 as bait protein, indicating a direct interaction between them. Overexpression of ApoA5 led to an increase in co-localization of Mfge8 with ApoA5 or LAMP2 in cardiomyocytes under lipid deposition status. On this basis, exogenous added recombinant rMfge8 counteracted the improvement of lipid deposition in cardiomyocytes by ApoA5. The above results indicate that the overexpression of ApoA5 can reduce fatty acid uptake in myocardial cells under lipid deposition status by regulating the content and cellular localization of Mfge8 protein, thereby significantly reducing myocardial lipid deposition and improving cardiac diastolic and systolic function.
Animals ; Humans ; Mice ; Myocytes, Cardiac/metabolism* ; Obesity/physiopathology* ; Male ; Apolipoprotein A-V/blood* ; Lipid Metabolism/physiology* ; Milk Proteins/blood* ; Myocardium/metabolism* ; Diet, High-Fat ; Antigens, Surface/physiology* ; Mice, Inbred C57BL ; Cells, Cultured ; Female

AIM: To investigate the effects of Conbercept on various optical coherence tomography(OCT)biomarkers in patients with retinal vein occlusion-related macular edema(RVO-ME), and to analyze the correlation of these biomarker changes with visual prognosis.METHODS: Retrospective study. A total of 57 patients(57 eyes)with RVO-ME, including 25 patients(25 eyes)with central retinal vein occlusion(CRVO)and 32 patients(32 eyes)with branch retinal vein occlusion(BRVO), were enrolled in this study. All the patients received intravitreal injection of conbercept once a month, three times in total. The preoperative and postoperative best-corrected visual acuity(BCVA), and changes in OCT biomarkers, including central macular thickness(CMT), the length of disorganization of the retinal inner layers(DRIL), the number of hyperreflective dots(HRD), the area of intraretinal fluid(IRF), the area of subretinal fluid(SRF), and the length of ellipsoid zone(EZ)disruption were compared. Furthermore, the relationship of these changes with BCVA was analyzed.RESULTS:Compared with the baseline, at 3 mo post-treatment, BCVA(LogMAR)was improved, CMT was decreased, the length of DRIL was shortened, the number of HRD was reduced, the area of IRF was decreased, the area of SRF was reduced, and the length of EZ disruption was shortened(all P<0.05). Spearman correlation analysis showed that there was no correlation between the changes in CMT, the length of DRIL, the number of HRD, the area of IRF, the area of SRF and the change in BCVA before and after treatment(P>0.05). However, the change in the length of EZ disruption was positively correlated with the change in BCVA(rs=0.34, P=0.011), and the R2 value of the fitting curve between the change in the length of EZ disruption and the change in BCVA was 0.113(P=0.011). When comparing the pre- and post-treatment changes in BCVA, the length of DRIL, the number of HRD, the area of IRF, the area of SRF, and the length of EZ disruption between patients in the CRVO group and BRVO group, no significant differences were observed(all P>0.05). In contrast, a significant difference was found in the change in CMT between the two groups(P=0.002).CONCLUSION:Conbercept effectively improves multiple OCT biomarkers in patients with RVO-ME. Repair of EZ disruption is a key driver of visual recovery, and its stability may serve as a novel indicator for personalized decision-making in anti-vascular endothelial growth factor therapy.

Objective To explore the risk factors of nonalcoholic fatty liver disease(NAFLD)in obese children,and evaluate the diagnostic value of each index for NAFLD and establish a Nomogram prediction model.Methods A total of 207 obese children admitted at Department of Pediatrics the Second Hospital of Jiaxing from January 2022 to January 2025 were selected.These children were divided into two groups based on NAFLD diagnosis:non-NAFLD group(n=99)and NAFLD group(n=108).Differences in gender,age,body mass index(BMI),and related metabolic indicators were compared between two groups.Logistic regression was employed to analyze potential risk factors for NAFLD development,while receiver operating characteristic(ROC)curve and Nomograms were used to evaluate the predictive value of different factors for NAFLD.Results ROC curve analysis demonstrated diagnostic value for NAFLD in triglyceride-glucose index(TyG),triglyceride-to-cholesterol ratio,TyG-waist circumference,and TyG-BMI.Among these,the area under the curve(AUC)of TyG showed the highest value of 0.713,with an optimal cutoff of 8.189,sensitivity of 50.5％and specificity of 83.3％.Univariate Logistic regression analysis revealed multiple insulin resistance indicators associated with NAFLD development.Multivariate analysis identified homeostatic model assessment of insulin resistance(HOMA-IR)and TyG as independent risk factors,with TyG showing the best predictive value(OR=3.038 95％CI:1.089-8.475,P＜0.05).The constructed Nomogram prediction model demonstrated strong comprehensive discriminant capability(AUC=0.742).Conclusion The Nomogram model based on HOMA-IR,TyG and its derived indexes has certain clinical application value in the screening of NAFLD in children.

This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

Objective:To assess the association of single nucleotide polymorphisms (SNP) of the cell division cycle 42 ( CDC42) gene with Pulmonary artery systolic pressure (PASP) among patients with Congenital heart disease (CHD). Methods:In this observational study, clinical data and blood samples were collected from 579 CHD patients with left-to-right shunt who presented to our hospital between January 2012 and January 2017. SNPs of the CDC42 gene were genotyped using an improved multiple ligase detection reaction. Multiple linear regression was applied to evaluate the association of CDC42 gene variants with PASP. This study was approved by the Medical Ethics Committee of the First Affiliated Hospital of Xinjiang Medical University (Ethics No.: 20180222-102). Results:Polymorphisms at rs2501256 and rs34896897 of the CDC42 gene were significantly associated with PASP. Compared with the CC genotype at rs2501256, TT and CT carriers displayed higher PASP [TT vs. CC: B (95% CI) = 4.01 (1.95, 6.07), P<0.001; CT vs. CC: B (95% CI)=2.91 (0.63, 5.19), P< 0.001]. Similarly, GG and GA genotypes at rs34896897 were associated with higher PASP compared to the AA genotype [GG vs. AA: B (95% CI) = 26.15 (20.45, 31.84), P<0.001; GA vs. AA: B (95% CI)=7.19 (4.31, 10.08), P<0.001]. Genetic model analyses demonstrated significant differences for both rs2501256 and rs34896897 under dominant, additive, and recessive models ( P<0.05). TT carriers at rs2501256 exhibited larger left-and right-atrial diameters, whereas GG carriers at rs34896897 showed greater right-atrial and right-ventricular end-diastolic dimensions. Subgroup analyses revealed no association between rs2501256 and PASP in males, individuals younger than 18 years, Uyghur ethnicity, or those with ventricular septal defects. Conclusion:CHD patients carrying the minor alleles of rs2501256 and rs34896897 in the CDC42 gene present higher incidence of PASP compared to those carrying the common alleles.

Objective:To improve the isolation and culture method of seasonal influenza virus in embryonated chicken eggs (ECEs), and evaluate their isolation efficiency.Methods:We randomly selected 80 positive samples of H1N1 (H1N1pdm09) and seasonal H3N2 (H3N2snl) influenza virus nucleic acid, and inoculated them into the amniotic and urinary sac cavities of 10-day-old (traditional method) and 14-day-old (improved method) ECEs respectively to adapt the virus to the ECEs (E1-E2). Both method were used to inoculate 10-day-old urinary sac amplification virus (E2-E3), and the final virus isolation positive rates of the two method were compared; using fluorescence quantitative PCR method to detect viral nucleic acids in the improved amniotic and urinary sac cultures, and evaluate the viral proliferation at different inoculation sites; we analyzed the correlation between virus content and isolation positivity rate in the original specimen based on the CT value of nucleic acid testing and the final virus isolation positivity rate using the improved method.Results:The improved method obtained 42 strains of H1N1pdm09 strain, with a positive rate of 52.5% ( χ2=38.571, P<0.01); obtained 54 strains of H3N2snl strain, with a positive rate of 67.5% ( χ2=40.921, P<0.01). Significant differences were observed in the isolation efficiency of H1N1pdm09 samples when the improved method was applied to different inoculation sites of chicken embryos ( χ2=30.476, P<0.01), and similar differences were noted for H3N2snl samples ( χ2=4.928, P=0.026). There was no significant difference in the isolation rate of different CT value intervals of the original samples ( χH1N1pdm092=10.226, χH3N2snl2=3.764, P>0.05). Conclusions:The improved method of inoculating 14-day old ECEs adapted the virus, and the final number of strains obtained was significantly higher than the traditional method of inoculating 10 day old ECEs, which can significantly improve the positive isolation rate of H1N1pdm09 and H3N2snl influenza virus in ECEs. The amniotic cavity is more sensitive to H1N1pdm09 and H3N2snl influenza viruses, which helps the virus adapt in ECEs. There was no significant difference in the sample isolation rate and total positive rate of virus isolation among different CT value ranges, and further verification is needed.

Objective:To evaluate the effect of continuous theta burst stimulation (cTBS) on postoperative cognitive dysfunction (POCD) in mice and its association with the excitability of parvalbumin (PV) neurons in the medial prefrontal cortex (mPFC).Methods:Twenty-four specific pathogen-free healthy male C57BL/6 mice, aged 8 weeks, weighing 18-24 g, in which adeno-associated virus (AAV) for labeling PV neurons was injected into the mPFC using stereotaxic surgery, were used in this study. Three weeks later, the mice were divided into 3 groups ( n=8 each) using a random number table method: control group (group C), POCD group (group P) and cTBS group. Group C received no treatment. A mouse model of POCD was established by performing tibial fracture surgery under sevoflurane anesthesia and the mice received sham stimulation from postoperative day 0 to day 4 in group P. Group cTBS underwent POCD model establishment and received cTBS stimulation from postoperative day 0 to day 4. Cognitive function was assessed using contextual fear conditioning, Y-maze and novel object recognition tests on postoperative day 5. The spontaneous firing frequency of PV neurons in the mPFC was then measured using ex vivo patch-clamp electrophysiology. Results:The results of contextual fear conditioning test showed that compared to group C, the percentage of freezing time was significantly increased in group P ( P<0.05); compared to group P, the percentage of freezing time was significantly decreased in group cTBS ( P<0.05). The results of Y-maze test showed that compared to group C, the alternation accuracy was significantly decreased in group P ( P<0.05); compared to group P, the alternation accuracy was significantly increased in group cTBS ( P<0.05). The results of novel object recognition test showed that compared to group C, the percentage of time spent exploring the novel object was significantly decreased in group P ( P<0.05); compared to group P, this percentage of time spent exploring the novel object was significantly increased in group cTBS ( P<0.05). The results of ex vivo patch-clamp electrophysiology showed that compared to group C, the spontaneous firing frequency of PV neurons in the mPFC was significantly decreased in group P ( P<0.05); compared to group P, the spontaneous firing frequency of PV neurons in the mPFC was significantly increased in group cTBS ( P<0.05). Conclusions:cTBS can ameliorate POCD in mice, and the mechanism is related to the restoration of excitability of PV neurons in the mPFC.