BackgroundStudents in secondary vocational health school are at the age of puberty and prone to depressive symptoms. Peer victimization and social media addiction are found to be crucial in influencing the development of depression， and positive mental health has been proven to alleviate depressive symptoms， whereas there remains a striking lack of research on the mediating role of positive mental health and social media addiction in the relationship between peer victimization and depressive symptoms among secondary vocational health school students. ObjectiveTo explore the relationship between peer victimization and depressive symptoms and investigate the mediating role of positive mental health and social media addiction， so as to provide references for the prevention of depression among secondary vocational health school students. MethodsFrom October to December 2020， a cluster sampling framework was utilized to recruit 7 307 students from a secondary vocational health school in Luzhou City， Sichuan Province. Assessments were performed using Multidimensional Peer Victimization Scale （MPVS）， Warwick-Edinburgh Mental Well-being Scale （WEMWBS）， Bergen Social Media Addiction Scale （BSMAS） and Patient Health Questionnaire Depression Scale-9 item （PHQ-9）. Spearman correlation analysis was calculated to determine correlations between scores of scales， Process 4.0 was employed to test the mediation effect， and the bias-corrected Bootstrap procedure was used to test the significance of the mediation effect. ResultsA total of 7 044 （96.40%） valid questionnaires were collected. And 4 391（62.34%）students were found to have depressive symptoms. Correlation analysis revealed that PHQ-9 score was positively correlated with BSMAS score and MPVS score （r=0.404， 0.506， P<0.01）. WEMWBS score was negatively correlated with PHQ-9 score， BSMAS score and MPVS score （r=-0.587， -0.259， -0.358， P<0.01）. BSMAS score was positively correlated with MPVS score （r=0.328， P<0.01）. Positive mental health played a mediating role in the relationship between peer victimization and depressive symptoms， with an indirect effect value of 0.130 （95% CI： 0.119~0.141）， accounting for 30.81% of the total effect. Social media addiction also mediated the relationship between peer victimization and depressive symptoms， with an indirect effect value of 0.052 （95% CI： 0.045~0.059）， accounting for 12.34% of the total effect. Positive mental health and social media addiction exhibited a chained mediation effect on the relationship between peer victimization and depressive symptoms， with an indirect effect value of 0.012 （95% CI： 0.010~0.014） and accounting for 2.84% of the total effect. ConclusionPeer victimization can affect the presence of depressive symptoms among secondary vocational health school students both directly and indirectly through either separate or chained mediation of positive mental health and social media addiction.

Sensorineural hearing loss (SNHL), the most commonly-occurring form of hearing loss, is caused mainly by injury to or the loss of hair cells and spiral ganglion neurons in the cochlea. Numerous environmental and physiological factors have been shown to cause acquired SNHL, such as ototoxic drugs, noise exposure, aging, infections, and diseases. Several programmed cell death (PCD) pathways have been reported to be involved in SNHL, especially some novel PCD pathways that have only recently been reported, such as ferroptosis, necroptosis, and pyroptosis. Here we summarize these PCD pathways and their roles and mechanisms in SNHL, aiming to provide new insights and potential therapeutic strategies for SNHL by targeting these PCD pathways.
Humans ; Hearing Loss, Sensorineural/metabolism* ; Necroptosis/drug effects* ; Pyroptosis/drug effects* ; Ferroptosis/drug effects* ; Animals

OBJECTIVE To investigate the effects and mechanism of galangin （GAL） on hepatocyte apoptosis in rats with obstructive jaundice （OJ） based on the Janus kinase 2 （JAK2）/signal transduction and activator of transcription 3 （STAT3） signaling pathway. METHODS Taking male SD rats as the object， the OJ model was established by double ligation of common bile duct， and 48 rats with successful modeling were randomly separated into OJ model group （model group）， low-dose GAL group （GAL-L group）， high-dose GAL group （GAL-H group） and high-dose GAL+JAK2 activator colivelin group （GAL-H+ colivelin group）， with 12 rats in each group； another 12 SD rats with laparotomy/abdominal closure without ligation were selected as sham operation group （sham group）. Each administration group was given relevant medicine intragastrically and/or intraperitoneally， once a day， for 7 consecutive days. After the last medication， the morphology of liver tissue in rats was observed； the serum levels of total bilirubin （TBIL）， direct bilirubin （DBIL）， alanine transaminase （ALT） and γ -glutamyltransferase （GGT）， as well as the levels of superoxide dismutase （SOD） and malondialdehyde （MDA） in mail：guoweishengjcy@126.com liver tissue were detected. The apoptotic rate of liver tissue cells， the expression levels of signaling pathway-related proteins （phosphorylated JAK2， JAK2， phosphorylated STAT3， STAT3） and apoptosis-related proteins [B cell lymphoma 2 （Bcl-2）， Bcl-2 related X protein （Bax）] were determined. RESULTS Compared with sham group， congestion of liver sinusoids， damage to liver lobules， disordered arrangement and swollen morphology of liver cells， the disappearance of nucleoli， and significant infiltration of inflammatory cells and fibrous tissue proliferation were observed in model group； the serum levels of TBIL， DBIL， ALT and GGT， the level of MDA in liver tissue， the apoptosis rate of liver cells， the protein expression of Bax， and the protein phosphorylation levels of JAK2 and STAT3 in liver tissue of model group were increased significantly （P＜0.05）； the level of SOD and the protein expression of Bcl-2 in liver tissue were decreased significantly （P＜0.05）. Compared with the model group， the pathological injuries of liver tissue were relieved in GAL-L group and GAL-H group， all quantitative indicators had significantly improved， and the effect of GAL-H group was more significant （P＜ 0.05）. Colivelin could significantly reverse the improvement effects of GAL on liver injury and related indicators of OJ rats （P＜ 0.05）. CONCLUSIONS GAL may inhibit liver cell apoptosis in OJ rats， improve liver function and alleviate oxidant stress， the mechanism of which may be associated with inhibiting JAK2/STAT3 signaling pathway.

Most solid tumors suffer from inadequate blood perfusion and oxygenation, leading to a hypoxic microenvironment that accelerates tumor progression and adversely impacts prognosis. Thus, improving oxygenation in tumor tissues is crucial for enhancing the sensitivity and efficacy of tumor therapy. Hemoglobin-based oxygen carriers (HBOCs), as a type of oxygen-carrying nanoparticles, can not only carry and release oxygen but also reach the small blood vessels of obstructive microcirculation to deliver oxygen for anoxic tissues and organs, which are difficult for normal red blood cells to pass through. Studies have demonstrated that the application of HBOCs as a potential nanoscale efficient oxygen carrier in tumor therapy can enhance tissue oxygenation and hold great promise for applications in tumor therapy.This review summarizes the impact of hypoxia in tumors and highlights the progress and potential mechanisms of using HBOCs in tumor radiotherapy, chemotherapy, new kinetic therapy and immunotherapy.

Objective To observe the feasibility of cardiac MR tissue tracking(CMR-TT)technique for quantitatively evaluating myocardial strain of patients with myocardial amyloidosis(CA).Methods Cardiac MRI were collected from 20 patients of immunoglobulin amyloid light-chain CA(AL-CA,group A),20 cases of transthyretin CA(ATTR-CA,group B)and 20 healthy subjects(group C),and myocardial strain parameters were obtained using CMR-TT technique.Left ventricular cardiac function parameters were compared among 3 groups,so were strain parameters of each myocardial segment of left ventricle and global myocardium,including 3D longitudinal strain(LS),3D radial strain(RS)and 3D circumferential strain(CS).Results Compared with those in group C,significant differences of left ventricular cardiac function parameters were found in both group A and B(all P＜0.01),while no statistical difference was found between group A and B(all P＞0.05).Except for apical segment RS(P=0.81),strain parameters in group A and B were both lower than those in group C(all P＜0.01),while no significant difference was detected between group A and B(all P＞0.05).Conclusion CMR-TT technique could be used to quantitatively evaluate left ventricular myocardial strain of CA patients.

Objective:To investigate the recognition of the post competency index system among rural general practice assistant physicians and its influencing factors.Methods:This study was a cross-sectional survey. A questionnaire survey on the recognition of post competency index system was conducted from October 2020 to September 2021 among rural general practice assistant physicians from 10 provinces/municipalities selected by stratified cluster sampling method. The recognition of rural general practice assistant physicians at all levels of indexs and the factors influencing recognition were analyzed.Results:A total of 1 123 questionnaires were distributed and 1 024 valid ones were collected with a recovery rate of 91.18%. Of the 1 024 respondents, 529 were male(51.7%) and 435 were aged 40-49 years(42.5%), which was the highest proportion by age group. The average overall recognition score of the index system was 4.41, and the scores of the primary indexes were 4.32-4.45. Three primary indexes had the highest recognition scores: professional competence, basic health care services, and interpersonal communication and teamwork. The recognition scores on the second level index were 4.18-4.61, and the proportion of recognition scores greater than 4 was over 80%. There were significant differences in the recognition scores of the index system among assistant physicians with different working years, educational background, professional title and work unit ( F/H=6.41, 14.83, 12.45, 7.53, P<0.01). Educational background(associate degree: B=0.091, P=0.015; bachelor degree and above: B=0.196, P<0.001) and professional title(intermediate professional title and above: B=-0.234, P<0.001) were the independent factors influencing the recognition degree of the index system for rural general practice assistant physicians. Conclusions:The post competency index system is generally recognized by rural general practice assistant physician, and academic qualifications and professional title status may influence its recognition.

Objective:To evaluate the application feasibility of the post competency index system of rural general practice assistant physicians, and to analyze and compare the post competency of rural general practice assistant physicians with different characteristics through a survey among rural general practice assistant physicians in China.Methods:This study was a cross-sectional study. A questionnaire survey was conducted among rural general practice assistant physicians in 10 provinces/municipalities selected by stratified cluster sampling method from October 2020 to September 2021. The post competency scores were self-evaluated based on the post competency index system of rural general practice assistant physicians. The results of the survey were analyzed and the application feasibility of the index system was evaluated.Results:A total of 1 123 questionnaires were distributed and 1 024 valid questionnaires were returned with a recovery rate of 91.2%. Of the 1 024 respondents, 529 were males (51.7%), 435 were aged 40-49 years (42.5%), 434 had a secondary school education or less (42.4%), and 531 were junior practitioners (51.9%). The Cronbach′s α coefficient of the overall questionnaire was 0.987, and the Cronbach′s α coefficient of the first level index ranged from 0.897 to 0.974. The cumulative variance contribution rate of exploratory factor analysis was 72.012%. The confirmatory factor analysis showed χ2/ df=3.926, RMSEA=0.076, CFI=0.858, IFI=0.859, indicating that the model fit was basically good. The average self-evaluation scores of the first level index ranged from 3.95 to 4.25, and the average self-evaluation scores of the second level index ranged from 3.74 to 4.36. There were significant differences in self-evaluation scores of post competency among rural general practice assistant physicians with different working years, professional titles, working units and economic regions( F=4.67, 10.54, 22.16 and 20.90,all P<0.05). People with low self-evaluation scores of post competency had the following characteristics: working 10-19 years, intermediate or above titles, working in community health service centers, located in the eastern region.People with high self-evaluation scores of post competency had the following characteristics: primary professional title, working in the village clinic. Conclusion:The competency index system of rural general practice assistant physicians has good application feasibility,and it can be used to evaluate post competency for the education and training of rural general practice assistant physicians.

【Objective】 To understand factors associated with children′s attendance at nursery care institutions (NCIs) and the basic characteristics of the NCIs children were enrolled in, so as to provide scientific evidence for policymakers. 【Methods】 During November 2020 and January 2021, parents who visited the Department of Child Health Care in six selected maternal and children′s hospitals, as well as nearby NCIs in Zhejiang were invited to finish an online questionnaire. Information such as children′s sociodemographic characteristics, parents′ knowledge, attitude and practice regarding nursery and feeding, etc. were collected. A total of 1 756 questionnaires were collected. 【Results】 Compared to children who were not in NCIs, children enrolled in NCIs were older (94.4% of children ≥24 months vs. 30.1%, χ²=835.27), more likely to be from the local area (87.2% vs. 81.4%,χ²=12.25), more likely to have parents with a college degree (mother: 83.6% vs. 74.2%, χ²=35.29; father: 79.9% vs. 70.0%, χ²=27.01), had a higher prevalence of family annual income >200 000 CNY (49.5% vs. 28.2%, χ²=110.49), and were less likely to have their grandparents available to take care of them (16.7% vs. 26.8%, χ²=31.4) The difference all have great significant.(P<0.05). In a multivariate Logistic regression model, the older the child, the more likely they were to attend an NCI (for children aged 6 - 23 months, OR=6.70; for children aged 24 - 35 months, OR=134.03; and for children aged 36 - 42 months, OR=699.33; P<0.05). Family annual income was positively associated with children′s attendance at NCIs (for those earning 100 000 - 200 000 CNY/year, OR=1.63; for those earning 200 000 - 500 000 CNY/year, OR=2.96; and for those earning >500 000 CNY/year, OR=4.62, P<0.05). Conversely, the higher the level of grandparent involvement in daily care, the lower the attendance at NCIs (for children cared for by both parents and grandparents, OR=0.57; for those primarily cared for by grandparents, OR=0.26, P<0.05). For children who used to stay at NCIs, 82.8% stayed at institutions that only recruited children aged 0 - 3 years, 97.4% spent their whole day in NCIs, and 71.4% spent less than 3 000 CNY per month for NCI services. Additionally, over 95% of parents were satisfied with the food and care services in NCIs, as well as their children′s physical development in NCIs. However, 32.1% of NCIs were reported by parents as having no room for breastfeeding. 【Conclusions】 Children′s age, grandparent involvement in routine care, and family annual income are the main factors associated with children′s attendance at NCIs. There is a greater need for more affordable and community-based NCIs, particularly for children under 2 years old. Additionally, more attention should be paid to the quality surveillance, assessment and management of NCIs.

BACKGROUND:Red light irradiation and silver ion dressing are mostly used to treat chronic difficult healing wounds clinically,but the optimal irradiation time of red light irradiation and silver ion dressing for chronic non-healing wounds,and the combination of different silver ion dressings have not been determined. OBJECTIVE:To investigate the optimal irradiation time and dressing combination of red light and silver ion dressing in the therapy of chronic non-healing wounds. METHODS:The chronic non-healing wound model was made by applying Staphylococcus aureus on the whole skin defect and subcutaneous hydrocortisone injection in SD rats.72 rat models were randomly divided into 4 groups with 18 rats in each group by random number table method.The rats were treated on the basis of standard dressing change and the following therapy:A1B1 group(red irradiation 20 minutes + lipid hydrocolloidal silver sulfate dressing),A1B2 group(red light irradiation 20 minutes + calcium alginate fiber dressing),A2B1 group(red light irradiation 30 minutes + lipid hydrocolloidal silver sulfate dressing),and A2B2 group(red light irradiation 30 minutes + calcium alginate fiber dressing);change dressing,irradiate once,and change dressing every 24 hours.After 14 days of continuous treatment,wound healing rate,bacterial colony number,inflammatory response,histomorphology and angiogenesis were detected in each group. RESULTS AND CONCLUSION:(1)With the extension of treatment time,the wound healing rate of rats in the four groups was increased,and the wound healing rate of rats in the A2B2 group at 3,7,and 14 days after treatment was higher than that in the other three groups(P<0.05).(2)The wound bacterial culture results on day 7 after treatment demonstrated that the number of bacterial colonies in the A2B2 group was lower than that in the other three groups(P<0.05).Western blot assay exhibited that with the extension of treatment time,the protein expressions of tumor necrosis factor α and interleukin-6 in wound tissue of rats in the four groups were decreased,while the protein expressions of interleukin-10 were increased.The protein expressions of tumor necrosis factor α and interleukin-6 in the A2B2 group were lower than those in the other three groups(P<0.05).The protein expression of interleukin-10 in the A2B2 group was higher than that of the other three groups(P<0.05).(3)The wound hematoxylin-eosin staining on day 14 after treatment demonstrated that a large number of collagen fibers in the A2B2 group were parallel distributed and the most closely connected,which was significantly better than the other three groups.(4)The results of immunofluorescence staining indicated that the fluorescence intensity expression of CD31 in the A2B2 group was higher than that in the A1B1,A1B2 and A2B1 groups(P<0.05).q-PCR detection at 3,7,and 14 days after treatment exhibited that the mRNA expressions of vascular endothelial growth factor a and vascular endothelial growth factor receptor 2 in the A2B2 group were higher than those in the other three groups(P<0.05).Western blot assay at 3,7 and 14 days after treatment revealed that the protein expressions of vascular endothelial growth factor a and vascular endothelial growth factor receptor 2 in the A2B2 group were higher than those in the other three groups(P<0.05).(5)These findings confirm that 30 minutes of red light irradiation combined with silver alginate fiber dressing has better results in treatment of chronic non-healing wounds.