BACKGROUND:Studies have shown that metformin has anti-inflammatory,anti-tumor,anti-aging and vasoprotective effects,and can inhibit the progression of osteoarthritis,but its specific mechanism of action remains unclear. OBJECTIVE:To investigate the mechanism of metformin on cartilage protection in a rat model of osteoarthritis. METHODS:Forty male Sprague-Dawley rats were randomly divided into four groups(n=10 per group):blank,control,sham-operated,and metformin groups.The blank group did not undergo any surgery.In the sham-operated group,the joint cavity was exposed.In the model group and the metformin group,the modified Hulth method was used to establish the osteoarthritis model.At 1 day after modeling,the rats in the metformin group were given 200 mg/kg/d metformin by gavage,and the model,blank,and sham-operated groups were given normal saline by gavage.Administration in each group was given for 4 weeks consecutively.Hematoxylin-eosin staining,toluidine blue staining,and safranin O-fast green staining were used to observe the morphological structure of rat knee joints.Immunohistochemical staining and western blot were used to detect the protein expression of SOX9,type Ⅱ collagen,a disintegrin and metalloproteinase with thrombospondin motifs 5(ADAMTS5),Beclin1,P62,phosphatidylinositol 3-kinase(PI3K),p-PI3K,protein kinase B(AKT),p-AKT,mammalian target of rapamycin(Mtor),and p-Mtor in rat cartilage tissue. RESULTS AND CONCLUSION:The results of hematoxylin-eosin,toluidine blue and safranin O-fast green staining showed smooth cartilage surface of the knee joints and normal histomorphology in the blank group and the sham-operated group,while in the model group,there was irregular cartilage surface of the knee joint and cartilage damage,with a decrease in the number of chondrocytes and the content of proteoglycans in the cartilage matrix.In the metformin group,there was a significant improvement in the damage to the structure of the cartilage in the knee joints of the rats,and the cartilage surface tended to be smooth,with an increase in the number of chondrocytes and the content of proteoglycans in the cartilage matrix.Immunohistochemistry staining and western blot results showed that compared with the control and sham-operated groups,the expression of SOX9,type Ⅱ collagen,and Beclin1 proteins in the cartilage tissue of rats in the model group was significantly decreased(P<0.05).Conversely,the expression of ADAMTS5,P62,as well as p-PI3K,p-AKT,and p-Mtor proteins was significantly increased(P<0.05).Furthermore,compared with the model group,the expression of SOX9,type Ⅱ collagen,and Beclin1 proteins in the cartilage tissue of rats in the metformin group was significantly increased(P<0.05),while the expression of ADAMTS5,P62,as well as p-PI3K,p-AKT,and p-Mtor proteins was significantly decreased(P<0.05).To conclude,Metformin can improve the autophagy activity of chondrocytes and reduce the degradation of cartilage matrix in osteoarthritis rats by inhibiting the activation of PI3K/AKT/Mtor signaling pathway,thus exerting a protective effect on articular cartilage.

BACKGROUND:Previous research by the research team found that domestically produced porous tantalum is beneficial for early adhesion and proliferation of MG63 cells,and can be used as a scaffold material for bone tissue engineering. OBJECTIVE:To investigate the effect of domestic porous tantalum modified by osteogenic induction factor slow-release system on the adhesion,proliferation,and differentiation of MG63 cells. METHODS:Osteogenic induction factor slow-release system was constructed by adding 15%volume fraction of osteogenic factor solution to poly(lactic-co-glycolic-acid)gel.The passage 3 MG63 cells were inoculated on a porous tantalum surface(control group),porous tantalum surface coated with poly(lactic-co-glycolic-acid)copolymer gel(gel group),and porous tantalum surface coated with osteoblastic induction factor slow-release system(slow-release system group),and co-cultured for 5 days.The surface cytoskeleton of the material was observed by phalloidine staining.Cell proliferation was detected by flow cytometry.Western blot assay and RT-qPCR were used to detect the protein and mRNA expressions of type Ⅰ collagen,osteopontin,and RUNX-2 on the surface cells of the material. RESULTS AND CONCLUSION:(1)Phalloidine staining showed that MG63 cells adhered to and grew on the surface and inside of the three groups of porous tantalum,and the matrix secreted by the cells covered the surface of the material.(2)Flow cytometry showed that the cell proliferation in the slow-release system group was faster than that in the control group and the gel group(P<0.05).(3)Western blot assay and RT-qPCR showed that the protein and mRNA expressions of type Ⅰ collagen,osteopontin,and RUNX-2 in the slow-release system group were higher than those in the control group and gel group(P<0.05).(4)The results showed that the domestic porous tantalum modified by the osteogenic induction factor slow-release system was beneficial to the adhesion,proliferation,and differentiation of MG63 osteoblasts.

Objective: To explore the relationship between depressive symptoms, negative life events and resilience among primary and secondary school teachers, so as to provide a reference for mental health promotion in school teachers. Methods: During November to December 2022, a questionnaire survey was conducted using convenient cluster sampling method to select 11 332 in service teachers from 38 schools in 8 provinces (cities) including Beijing, Guangdong, Anhui, Hubei, Sichuan, Xinjiang, Liaoning, and Heilongjiang. The Patient Health Questionnaire-9 items, a self developed 21-item Adverse Life Events questionnaire, and a 10-item Conner-Davidson Resilience Scale were used to assess depressive symptoms, experiences of negative life events, and resilience levels of the teachers, respectively. The relationship between depressive symptoms, negative life events and psychological resilience were analyzed by multiple linear regression and stratified regression. Results: The detection rate of depressive symptoms among primary and secondary school teachers was 14.0%. Negative life events of primary and secondary school teachers were positively correlated with depressive symptoms ( r =0.35), while psychological resilience was negatively correlated with depressive symptoms ( r =-0.45) ( P <0.05). After adjusting for possible covariates including gender and marital status, negative life events were positively correlated with depressive symptoms ( β=0.22, P <0.01). Resilience played a moderating role in the association of negative life events with depressive symptoms among primary and secondary school teachers ( B=-0.15, P <0.01). Conclusions Negative life events experiences are associated with higher level of depressive symptoms among school teachers. However, resilience might mitigate the negative effects of negative life events on depressive symptoms, playing a protective role in teachers mental health.

Objective:To investigate the effects of erythropoietin producing hepatocyte receptor A2 (EphA2) gene silencing on the growth, migration and invasion of human ovarian cancer HeyA8-MDR cells.Methods:After stable screening by plasmid and liposome mediated transfection, the expression of EphA2 protein was detected by Western blot. The effects of EphA2 gene silencing on the biological characters of HeyA8-MDR cells of ovarian cancer were observed by CCK-8 and Transwell chamber invasion assay.Results:Compared with HeyA8-MDR (negative control group) and HeyA8-MDR+ blank control group, the expression level of EphA2 protein in HeyA8-MDR+ experimental group was significantly decreased ( P<0.01). Cell proliferation, migration and invasion were inhibited ( P<0.05). Conclusions:EphA2 gene silencing can inhibit the growth, migration and invasion of HeyA8-MDR cells of ovarian cancer, providing a new idea for the treatment of ovarian cancer.

Objectives:To explore the risk factors for recurrent in-stent restenosis(R-ISR)in patients with coronary heart disease after percutaneous coronary intervention(PCI)and to develop a risk prediction model for R-ISR using a nomogram. Methods:All patients treated for ISR at the Fuwai Hospital,Chinese Academy of Medical Sciences from January to December 2017 were eligible for this study.A total of 1 102 ISR patients were included for analysis.Based on the recurrence of ISR after PCI,patients were divided into R-ISR group and non-R-ISR group.Univariate Cox regression analyses,LASSO regression analyses,and the combination of clinical experience were used to select predictors of R-ISR.A multivariate Cox regression model was used to analyze the independent risk factors of R-ISR and to develop a risk prediction model. Results:The median follow-up duration for participants was 1 264(1 169,1 334)days,the incidence rate of R-ISR after PCI was 10.1%.Multivariate Cox regression analysis showed that age(HR=0.98,95%CI:0.96-0.99),total bilirubin(HR=0.95,95%CI:0.91-0.99),apolipoprotein A1(HR=0.08,95%CI:0.02-0.42),high-sensitivity C-reactive protein(HR=1.05,95%CI:1.01-1.10),and reference vessel diameter(HR=0.65,95%CI:0.44-0.98)were independent determinants of R-ISR.Accordingly,the R-ISR risk prediction model was developed with a nomogram,the AUC of this model to predicto R-ISR was 0.70(95%CI:0.64-0.77). Conclusions:Coronary heart disease patients with younger age,lower levels of total bilirubin and apolipoprotein A1,smaller vessel diameter,and higher levels of high-sensitivity C-reactive protein are at higher risk of R-ISR.The developed visual risk prediction model for R-ISR shows promising predictive performance but still requires further optimization and validation.

Objectives:To evaluate the coronary microcirculatory function in patients with hypertrophic cardiomyopathy(HCM). Methods:Patients who diagnosed with HCM and underwent the measurement of index of microcirculatory resistance(IMR)using pressure-sensing guide wire from November 2021 to April 2023 were prospectively included.Coronary microcirculatory dysfunction(CMD)was defined as IMR≥25 U and patients were grouped accordingly to compare the clinical characteristics. Results:A total of 25 HCM patients were included.Mean age was(58.4±13.3)years,18 were men and mean body mass index was(26.7±3.6)kg/m2.Coronary microcirculatory function was successfully evaluated in all patients and the mean value of IMR was(30.5±15.3)U.There were 15 patients with CMD.Baseline clinical characteristics,laboratory examinations and medications were simialr between patients with and without CMD.The maximal left ventricular wall was significant thicker in patients with CMD compared with that in patients without CMD([20.2±2.8]mm vs.[16.9±2.3]mm,P=0.005).There was no significant difference in other echocardiographic parameters between two groups(all P>0.05).In the range of IMR value less than 50 U(n=22),there was a significant linear positive correlation between maximal left ventricular wall thickness and IMR(r=0.423,P=0.049).There was no significant difference in coronary flow reserve and fractional flow reserve between two groups. Conclusions:The severity of CMD is positively correlated with left ventricular wall thickness in HCM patients.

Objective: To understand knowledge of comprehensive sexuality education and its associated factors among junior high school teachers in six provinces in China, in order to provide a scientific basis for teacher training. Methods: From June to December 2021, a convenience sampling method was used to select 1 016 junior high school teachers from Beijing, Chongqing, Liaoning, Sichuan, Yunnan and Guangdong provinces. A structured questionnaire was used to investigate teachers knowledge of comprehenswe sexuality education. Binary Logistic regression was used to analyze the related influencing factors of the knowledge of comprehensive sexuality education among junior high school teachers. Results: The study showed that the knowledge rate of comprehensive sexuality education among middle school teachers was 58.1%, and the knowledge rate was higher in teachers who had conducted sexuality education to students( χ 2=9.42, P <0.01). The percentage of the correct answer on the prevention and control of sexually transmitted diseases(26.0%), the impact of inequality on love relationships( 33.6 %), and the impact of mass media on sexual cognition(68.8%) was the lowest. Regardless of whether they had implemented sexuality education for students, the knowledge and awareness rate of sexual knowledge among biology teachers, school doctors/health teachers and mental health teachers was higher( OR=2.32, 4.17, P <0.05). Conclusion Knowledge of comprehensive sexuality education among middle school teachers still needs to be improved. It is advisable to strengthen the training of comprehensive sexuality education for middle school teachers and focus on teachers of subjects related to comprehensive sexuality education.

Abstract Improving health literacy can effectively reduce the risk of health risk behaviors and adverse health outcomes in children and adolescents. Global research on health literacy of children and adolescents has been increasing in recent years. The paper reviews the existing research and proposes that there is no universal definition and connotation of health literacy for children and adolescents, most of the studies use or make some revisions on the definition of adult health literacy in child and adolescent health literacy, failing to consider developmental characteristics and unique health needs of children and adolescents. Moreover, the assessment index system and instruments are diversified, making the research findings from different studies difficult to compare, and to obtain consistent and reliable conclusions. Future endeavors are encoouraged to expand health literacy researches and to update more comprehensive and practical definition, and to develop a standardized assessment instrument that can be validated in Chinese culture.

Objective: To preliminarily develop Health Literacy Scale for pupils, providing a tool for dynamic monitoring and related health literacy research among pupils. Methods: Through policy and literature review, the health literacy evaluation index system of pupils was established. Through two rounds of expert consultation, the evaluation index system and scale item pool of three levels in primary school were formed, and "Evaluation Scale 1.0" was developed. Through two panel discussions, health education experts, teachers and students were invited to provide advices on the content, expression and structure of scale 1.0, turning it into "Evaluation Scale 2.0", and completing the preliminary development of the scale. Results: The health literacy assessment index system of primary school students includes three levels，including level-1 was Grade 1-2, level-2 was Grade 3-4,level-3 was Grade 5-6, covering two level indexes. The scale for primary school students contained five horizontal dimensions and four vertical dimensions. In the Delphi consultation, the response rate was 100%, and the authority coefficient was 0.85. After item selection and modification, the final version of level-1, level-2 and level-3 scales contained 36, 44 and 50 items respectively. Conclusion The development of Health Literacy Evaluation Scale for pupils has high applicability and practical value.

Objective:To investigate the application of serum creatinine to prealbumin ratio (Scr/PA) in the diagnosis of patients with heart failure complicated with renal failure.Methods:This was a case-control study. Patients with chronic heart failure and heart failure complicated with renal failure admitted to Dalian Central Hospital from January 5, 2020 to April 23, 2023 were retrospectively analyzed, and Scr/PA was calculated. The general data and laboratory examination indexes of the two groups were compared. According to the data type, t test, Wilcoxon rank sum test and χ 2 test were used for comparison between the two groups. The risk factors of heart failure complicated with renal failure were analyzed by univariate and multivariate logistic regression analysis, and Spearman correlation analysis was used to analyze the correlation between Scr/PA and N-terminal pro-B-type natriuretic peptide (NT-proBNP) and hemoglobin (HGB). ROC curve was used to determine the predictive value of Scr/PA and NT-proBNP for heart failure complicated with renal failure. Results:Compared with the heart failure group, Triglyceride [1.25 (0.94, 1.81) mmol/L vs. 1.07 (0.76, 1.46) mmol/L, Z=-2.159, P=0.031], D-dimer [2.30 (1.53, 4.67) mg/L vs. 1.63 (0.64, 2.96) mg/L, Z=-2.339, P=0.02],NT-proBNP [18 500 (9 575, 30 000) pg/ml vs. 4 865 (1 600, 9 800) pg/ml, Z=-5.637, P<0.001], Scr/PA [0.233 (0.188, 0.351) mg/mg vs 0.064 (0.044, 0.103) mg/mg, Z=-8.197, P<0.001] were higher in heart failure complicated with renal failure group. While albumin [(33.9±5.2) g/L vs. (36.3±4.3) g/L, t=-2.173, P=0.008], estimated glomerular filtration rate[12.86 (7.88, 17.40) ml/(1 min×1.73 m 2) vs. 65.82 (48.66, 86.32) ml/(1 min×1.73 m 2), Z=-9.794, P<0.001], and HGB [(91±24) g/L vs. (123±23) g/L, t=-7.489, P<0.001] were lower. Univariate logistic regression analysis showed that albumin ( OR=0.900, 95% CI 0.830-0.975, P=0.010), HGB ( OR=0.948, 95% CI 0.930-0.966, P<0.001), Scr/PA ( OR=1.639, 95% CI 1.346-1.957, P<0.001) were associated with heart failure complicated with renal failure. Multivariate logistic regression analysis showed that only Scr/PA was an independent risk factor for heart failure complicated with renal failure. The correlation coefficients of Scr/PA with NT-proBNP and HGB were r=0.578 and r=-0.559, respectively (all P<0.001). The area under the AUC curve of Scr/PA and NT-proBNP for predicting heart failure complicated with renal failure was 0.927 (95% CI: 0.881-0.973, P<0.001) and 0.797 (95% CI: 0.717-0.877, P<0.001), respectively. Conclusions:Scr/PA is an independent risk factor for heart failure complicated with renal failure, and it has a good correlation with NT-proBNP and HGB. Scr/PA is superior to NT-proBNP in predicting heart failure complicated with renal failure.