BACKGROUND:Periprosthetic joint infection is the most common cause of early failure after total knee replacement.The current methods of preventing periprosthetic joint infection by improving the surface of the prosthesis have limitations to varying degrees.OBJECTIVE:To construct a coating material that can stably improve the surface of the implant,prevent the initial floating bacterial infection of periprosthetic infection,and regulate the bone transfer function around the implant.METHODS:(1)Material preparation:YGF polypeptide(which promotes bone formation),LL-37 polypeptide(with antibacterial properties)and YGF+LL-37 composite peptide were prepared by Fmoc solid phase peptide synthesis technology.The titanium-based materials were immersed in the three polypeptide solutions for 2 hours to obtain YGF coating,LL-37 coating and composite peptide coating coated titanium sheets.(2)In vitro experiment:Uncoated titanium sheets and coated titanium sheets were co-cultured with Escherichia coli(or Staphylococcus aureus)and the colonies were counted by plate method.MC3T3 cells were inoculated on the surface of uncoated titanium sheet and coated titanium sheet,respectively.Alizarin red staining was used to observe the calcium salt deposition on the surface of the material.Western blot assay was used to detect the protein expression of RUNX2,osteocalcin,osteopontin,and bone morphogenetic protein 2.(3)Animal experiment:24 SD rats were randomly divided into three groups:the blank group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal;the control group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension;the experimental group(n=8)was implanted with composite peptide coated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension.After 5 weeks of implantation,micro-CT examination,hematoxylin-eosin staining and immunohistochemical staining of femur specimens were performed.RESULTS AND CONCLUSION:(1)In vitro experiment:Compared with uncoated titanium sheet and YGF coated titanium sheet,LL-37 coated and composite peptide coated titanium sheet could significantly inhibit the growth and reproduction of Escherichia coli and Staphylococcus aureus.Compared with uncoated titanium sheets and LL-37-coated titanium sheets,YGF-coated and composite peptide-coated titanium sheets could promote calcium salt deposition in osteoblasts and increase the protein expression of RUNX2,osteocalcin,osteopontin and bone morphogenetic protein 2.(2)Animal experiment:Micro-CT test showed that the control group had less bone mass than the blank group and the experimental group.Hematoxylin-eosin staining showed that there was a large amount of fibrous tissue around the nail channel in the control group,only a small amount of tissue fibrosis around the nail channel in the blank group,and only a small amount of tissue fibrosis around the nail channel in the experimental group.Immunohistochemical staining showed that the protein expression of interleukin 1β and tumor necrosis factor α in the control group was higher than that in the blank group and the experimental group,and the expression of osteocalcin,RUNX2 and osteopontin in the experimental group was higher than that in the blank group and the control group.(3)The results show that the titanium-based material coated with YGF+LL-37 composite peptide coating has good antibacterial ability and can promote bone transfer around the implant.

This study aimed to investigate the effects of zidovudine (AZT) on high-fat diet (HFD)-induced metabolic disturbances in rats and its underlying mechanisms. The HFD rat model was established, and the animals were divided into the control group, the model group, and the AZT-treated group at low (25 mg/kg) and high (50 mg/kg) doses. Metabolic phenotype, hepatic lipid deposition, oxidative stress, mitochondrial function, and peroxisome proliferator-activated receptor (PPAR) signaling were evaluated. AZT treatment significantly mitigated HFD-induced body weight gain and reduced both the mass and adipocyte size of inguinal and epididymal white adipose tissues; it also enhanced metabolic flexibility and improved glucose tolerance without elevating blood lactate levels. High-dose AZT further lowered hepatic triglyceride accumulation, ameliorated steatosis, and additionally, attenuated hepatic oxidative stress by increasing superoxide dismutase (SOD) activity and decreasing malondialdehyde (MDA) levels. Western blot analysis revealed that AZT upregulated hepatic PPARα and carnitine palmitoyltransferase 1α (CPT1α), while downregulating PPARγ expression. In conclusion, AZT effectively ameliorates HFD-induced metabolic disorders without inducing mitochondrial toxicity, which may be related to the promotion of fatty acid oxidation, the reduction of oxidative stress, and the modulation of both the PPAR signaling pathway and pyrimidine metabolism.

BACKGROUND:Periprosthetic joint infection is the most common cause of early failure after total knee replacement.The current methods of preventing periprosthetic joint infection by improving the surface of the prosthesis have limitations to varying degrees.OBJECTIVE:To construct a coating material that can stably improve the surface of the implant,prevent the initial floating bacterial infection of periprosthetic infection,and regulate the bone transfer function around the implant.METHODS:(1)Material preparation:YGF polypeptide(which promotes bone formation),LL-37 polypeptide(with antibacterial properties)and YGF+LL-37 composite peptide were prepared by Fmoc solid phase peptide synthesis technology.The titanium-based materials were immersed in the three polypeptide solutions for 2 hours to obtain YGF coating,LL-37 coating and composite peptide coating coated titanium sheets.(2)In vitro experiment:Uncoated titanium sheets and coated titanium sheets were co-cultured with Escherichia coli(or Staphylococcus aureus)and the colonies were counted by plate method.MC3T3 cells were inoculated on the surface of uncoated titanium sheet and coated titanium sheet,respectively.Alizarin red staining was used to observe the calcium salt deposition on the surface of the material.Western blot assay was used to detect the protein expression of RUNX2,osteocalcin,osteopontin,and bone morphogenetic protein 2.(3)Animal experiment:24 SD rats were randomly divided into three groups:the blank group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal;the control group(n=8)was implanted with uncoated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension;the experimental group(n=8)was implanted with composite peptide coated titanium nails in the femoral medullary canal+intra-articular injection of Staphylococcus aureus suspension.After 5 weeks of implantation,micro-CT examination,hematoxylin-eosin staining and immunohistochemical staining of femur specimens were performed.RESULTS AND CONCLUSION:(1)In vitro experiment:Compared with uncoated titanium sheet and YGF coated titanium sheet,LL-37 coated and composite peptide coated titanium sheet could significantly inhibit the growth and reproduction of Escherichia coli and Staphylococcus aureus.Compared with uncoated titanium sheets and LL-37-coated titanium sheets,YGF-coated and composite peptide-coated titanium sheets could promote calcium salt deposition in osteoblasts and increase the protein expression of RUNX2,osteocalcin,osteopontin and bone morphogenetic protein 2.(2)Animal experiment:Micro-CT test showed that the control group had less bone mass than the blank group and the experimental group.Hematoxylin-eosin staining showed that there was a large amount of fibrous tissue around the nail channel in the control group,only a small amount of tissue fibrosis around the nail channel in the blank group,and only a small amount of tissue fibrosis around the nail channel in the experimental group.Immunohistochemical staining showed that the protein expression of interleukin 1β and tumor necrosis factor α in the control group was higher than that in the blank group and the experimental group,and the expression of osteocalcin,RUNX2 and osteopontin in the experimental group was higher than that in the blank group and the control group.(3)The results show that the titanium-based material coated with YGF+LL-37 composite peptide coating has good antibacterial ability and can promote bone transfer around the implant.

Objective: To explore the association between mental health and muscle strength among Chinese adolescents aged 13- 18, providing a theoretical foundation and intervention strategies for mental health promotion. Methods: Data were obtained from the 2019 Chinese National Survey on Students Constitution and Health, including 98 631 Chinese adolescents aged 13- 18. Psychological distress was assessed by using the Kessler Psychological Distress Scale (K10), and mental well being was measured with the Warwick-Edinburgh Mental Well being Scale (WEMWBS). Based on the gender and age specific Z scores of various test items [grip strength, standing long jump, pull ups (for males), and sit ups (for females)], muscle strength index (MSI) was constructed to evaluate the comprehensive level of muscle strength in adolescents. According to the Dual factor Model (DFM) of mental health, participants were categorized into four groups:troubled, symptomatic but content, vulnerable, and complete mental health. Gender differences were analyzed by using Chi-square tests, trends were tested with Cochran-Armitage tests, and multinomial Logistic regression models were applied to assess associations between muscle strength and mental health among adolescents. Results: In 2019, 37.4% of Chinese adolescents aged 13-18 were reported of high mental distress, and 59.9% were reported of low mental well being. Boys had significantly lower rates of high mental distress (35.3%) and low mental well being (55.6%) compared to girls (39.4%, 64.3%), and the differences were of statistical significance ( χ 2=176.13, 780.42, both P <0.05). In 2019, the rate of complete mental health among adolescents showed a downward trend with increasing age ( χ 2 trend = 258.47) and a gradual upward trend with increasing muscle strength levels ( χ 2 trend =123.14)，and both boys and girls exhibited similar trends ( χ 2 trend =103.83, 168.46; 57.00 , 67.34) (all P <0.05). The results of the unordered multiclass Logistic regression model showed that after controlling for confounding factors such as age and gender, when the completely pathological group as a reference, for every 1 unit increase in MSI in adolescents, the likelihood of being in a completely mental health state increased by 29% ( OR = 1.29); for every unit increase in the Z-score for pull ups, the likelihood of being in a completely mental health state increased by 6% ( OR =1.06) among boys; for every 1 unit increase in sit up Z score, the likelihood of being in a completely mental health state increased by 19% ( OR =1.19) among girls (all P <0.05). Conclusions The mental health status of Chinese adolescents is not good enough. Muscle strength is positively associated with mental health.

Objective: To systematically review the development and changes in mental health policies within the National Outline for Children s Development in China from 1992 to 2030, providing a reference basis for future formulation of mental health policies among children and adolescent in China. Methods: Based on the four editions of the National Outline for Children s Development in China across different periods from 1992 to 2030, word frequency analysis was used to reveal shifts in policy priorities, and an internationally recognized framework for adolescent health policy analysis was applied to conduct a textual review. Results: Word frequency analysis revealed that the term "psychological" appeared 6 times in the National Outline for Children s Development in China (2001-2010) but increased to 20 times in the National Outline for Children s Development in China (2021-2030) (abbreviated as the National Outline of 2021), while the term "health" rose from 4 times in the National Outline for Children s Development Plan in China in the 1990s to 68 times in the National Outline of 2021. The scope of mental health policy interventions expanded to encompass five key areas:health, safety, education, welfare and legal protection. Textual analysis highlighted that the policies of the National Outline for Children s Development in China were demand driven, prioritized vulnerable groups and continuously broadened their coverage, emphasizing sustainability and appropriateness, and monitoring/evaluation mechanisms. By 2023, 42.3% of primary schools and 64.8% of secondary schools employed full time mental health education teachers. However, the National Outline for Children s Development in China lacked direct evidence of children and adolescents participation in policy formulation, and publicly available mental health data disaggregated by age and gender remained limited. Conclusion Mental health policies of children and adolescents in China have evolved from nonexistence to gradual refinement, yet institutionalized channels for youth involvement in policy development and evaluation remain insufficient, and transparency in age and gender specific mental health data needs improvement.

Objective:To explore the moderating and mediating roles of psychological resilience in the relationship between job satisfaction and depressive symptoms among petrochemical workers.Methods:In April 2022, a cluster sampling method was used to conduct a questionnaire survey among 1087 in-service employees of a petrochemical enterprise in Henan Province. A total of 861 questionnaires were recovered, including 857 valid ones, with an effective rate of 99.54%. Data on job satisfaction, psychological resilience, and depressive symptoms were collected using the 10-item Connor-Davidson Resilience Scale (CD-RISC-10), Job Satisfaction Questionnaire, and Patient Health Questionnaire-9 (PHQ-9). Spearman rank correlation analysis was applied to analyze the relationships among the scores of job satisfaction, psychological resilience, and depressive symptoms. Hierarchical linear regression analysis was used to test the moderating effect of psychological resilience, and the Bootstrap method was employed to verify the mediating effect of psychological resilience.Results:The scores of job satisfaction, psychological resilience, and depressive symptoms among petrochemical workers were 36.00 (31.00, 36.00) points, 36.00 (30.00, 41.00) points, and 7.00 (3.00, 9.00) points. The detection rate of depressive symptoms was 65.7% (563/857). Results of Spearman rank correlation analysis showed that job satisfaction of petrochemical workers was positively correlated with psychological resilience ( rs=0.270, P<0.01) and negatively correlated with depressive symptoms ( rs=-0.386, P<0.01), psychological resilience was negatively correlated with depressive symptoms ( rs=-0.515, P<0.01). Results of hierarchical linear regression analysis indicated that psychological resilience had no moderating effect on the relationship between job satisfaction and depressive symptoms of petrochemical workers ( b=0.001, P>0.05). Results of the mediating effect test showed that psychological resilience played a partial mediating effect in the relationship between job satisfaction and depressive symptoms ( P<0.01), with a mediating effect value of -0.071 (95% CI: -0.125, -0.045), accounting for 20.16% of the total effect. Conclusion:Psychological resilience exerts a partial mediating effect rather than a moderating effect in the relationship between job satisfaction and depressive symptoms among petrochemical workers.

Atherosclerosis is a chronic vascular wall disease.The clinical manifestations are abnormal lipid depo-sition,fibrous hyperplasia,calcium deposition,etc.under the intima of the affected artery lesions.Its initial link is re-lated to endothelial cell dysfunction,which can be triggered and aggravated by different risk factors of atherosclerosis,in-cluding oxidative stress,hemodynamic abnormalities,endothelial cell senescence and inflammation,etc.Exploring the mechanism of endothelial cell dysfunction is conducive to the discovery of potential treatments for atherosclerosis.This ar-ticle summarizes the mechanism and research progress of drug therapy for endothelial cell dysfunction in atherosclerosis.

Objective:To evaluate the changes in left ventricular structure and function in pregnant women with different severities of hypertensive disorders of pregnancy（HDP）using conventional echocardiographic parameters，strain，and tissue-tracking mitral annulus displacement（TMAD）parameters，and to validate and compare the application value of strain and TMAD parameters.Methods:A total of 148 singleton pregnant women with HDP and 100 healthy pregnant women（HP group）who attended the Third Affiliated Hospital of Zhengzhou University from October 2023 to July 2024 were selected. Conventional echocardiographic parameters，strain，and TMAD parameters were collected. Based on the severity of the disease，HDP patients were divided into the gestational hypertension group（GH group， n=49），non-severe preeclampsia group（NSPE group， n=35），and severe preeclampsia group（SPE group， n=64）. The differences in various parameters between the HP，GH，NSPE，and SPE groups were compared. The correlation between the displacement ratio of the midpoint of the mitral valve annulus in the apical 4-chamber（AP4 Midpt%），the displacement ratio of the midpoint of the mitral valve annulus in the apical 2-chamber（AP2 Midpt%）and left ventricular global longitudinal strain（LVGLS）were analyzed，and ROC curves were plotted to analyze and compare the diagnostic efficacies of LVGLS，AP4 Midpt% and AP2 Midpt% for left ventricular function changes in HDP pregnant women. Results:① The analysis revealed no statistically significant differences in maternal age and height between the HP group and the HDP subgroups（all P>0.05）. In contrast，statistically significant differences were observed in gestational age，systolic blood pressure，diastolic blood pressure，body mass index，and body surface area（all P<0.05）. Additionally，significant differences were noted in left ventricular mass，left ventricular interventricular septum thickness at end-diastole，left ventricular posterior wall thickness at end-diastole，left ventricular end-diastolic dimension，left ventricular end-systolic dimension，left ventricular end-diastolic volume，left ventricular end-systolic volume，and stroke volume between the HP group and the HDP subgroups（all P<0.05），while the difference in left ventricular ejection fraction was not statistically significant（ P>0.05）. ② Significant differences were identified in strain and TMAD parameters between the HP group and the HDP subgroups（all P<0.05），with LVGLS，AP4 Midpt% and AP2 Midpt% exhibited the largest effect sizes（ η p2=0.457，0.453，0.351）. A progressive decline in strain and TMAD parameters was observed as the severity of HDP increased. ③ There were strong positive correlations between AP4 Midpt%，AP2 Midpt% and LVGLS（ r=0.752，0.747；all P<0.001）. ④ LVGLS，AP4 Midpt% and AP2 Midpt% all demonstrated significant diagnostic efficacies for changes in left ventricular function in HDP（AUC=0.840，0.847，0.791），and the differences in AUC among the 3 curves were not statistically significant（all P>0.05）.⑤ The success rate of collecting TMAD parameters was significantly higher than that of strain parameters（99.24% vs. 93.58%， P<0.001）. Conclusions:As the severity of the disease worsens，the changes of left ventricular structure and function in pregnant women with HDP become more and more significant. Both strain and TMAD parameters can early and sensitively identify the subclinical damage of left ventricular systolic function in HDP pregnant women，and both of them have the same diagnostic value. TMAD parameters can be used as a reliable substitute parameter of LVGLS in HDP pregnant women.

Atherosclerosis is a chronic vascular wall disease.The clinical manifestations are abnormal lipid depo-sition,fibrous hyperplasia,calcium deposition,etc.under the intima of the affected artery lesions.Its initial link is re-lated to endothelial cell dysfunction,which can be triggered and aggravated by different risk factors of atherosclerosis,in-cluding oxidative stress,hemodynamic abnormalities,endothelial cell senescence and inflammation,etc.Exploring the mechanism of endothelial cell dysfunction is conducive to the discovery of potential treatments for atherosclerosis.This ar-ticle summarizes the mechanism and research progress of drug therapy for endothelial cell dysfunction in atherosclerosis.

Objective·To investigate the changes in transcriptome and chromatin accessibility during the differentiation of human embryonic stem cells(hESCs)into neural progenitor cells(NPCs)using in vitro differentiation models and high-throughput multi-omics sequencing technologies.Methods·hESCs were first induced to differentiate into NPCs in vitro using the embryoid body formation method,and cells at both stages were collected.The cell phenotypes were identified by reverse transcription-quantitative real-time PCR(RT-qPCR)and immunofluorescence(IF)staining.Transcriptome sequencing(RNA-seq)was conducted to detect and analyze the differentially expressed genes(DEGs)between hESCs and NPCs.The assay for transposase-accessible chromatin with high-throughput sequencing(ATAC-seq)was employed to assess chromatin accessibility changes between hESCs and NPCs.Motif enrichment analysis was performed on differentially accessible chromatin regions to discover potential regulatory transcription factors.Finally,an integrated analysis of RNA-seq and ATAC-seq data and the protein-protein interaction(PPI)network were performed to identify key genes and regulatory pathways involved in the early stages of neural differentiation in vitro.Results·Both RT-qPCR and IF results indicated that the expression levels of pluripotency markers(NANOG and POU5F1)were high at the hESC stage but significantly decreased at the NPC stage,while early neural differentiation markers(PAX6,SOX1,and NES)were minimally expressed at the hESC stage but markedly upregulated at the NPC stage.RNA-seq analysis revealed that compared to the hESC stage,there were 5 597 genes upregulated and 3 654 genes downregulated at the NPC stage.Gene function enrichment analysis showed that the upregulated genes at the NPC stage were enriched in the functions related to neural development.ATAC-seq analysis demonstrated a total of 27 491 genomic regions had significant changes in chromatin accessibility during the differentiation from hESC to NPC,with 12 381 regions showing increased accessibility and 15 110 regions showing decreased accessibility.Motif enrichment analysis revealed that transcription factor genes such as DLX1 and LHX2 might play an important role in the differentiation process from hESCs into NPCs.Integrated analysis of RNA-seq and ATAC-seq data revealed that overlapping genes with high expression at the NPC stage were mainly enriched in axon guidance,forebrain development,and neuron migration.After neural differentiation,the expression levels of CTNND2 and LHX2 genes increased,and the chromatin accessibility of related genomic regions also increased.PPI network analysis indentified candidate downstream genes including PRKACA,CDH2,and ERBB4.Conclusion·The in vitro differentiation model of hESCs combined with high-throughput multi-omics sequencing technologies can be used to depict the changes in transcriptome and chromatin accessibility during the differentiation of hESCs into NPCs.In this process,the expression levels of genes related to axon guidance,forebrain development,and neuronal migration pathways increase and related chromatin accessibility is enhanced.