Objective: To investigate the prevalence and associated factors of depressive symptoms among middle and high school students in Zhejiang Province, so as to provide scientific basis for the implementation of depressive intervention. Methods: Based on the health status and associated factors of middle and high school students in the project "Monitoring of Common Diseases and Health Influencing Factors of Students" during 2018 to 2021, a total of 73 309 students including middle school, ordinary high school and vocational high school surveyed in 11 cities of Zhejiang Province were selected by multi stage stratified cluster random sampling method. From 2018 to 2021, there were 6 008, 21 917, 23 712 and 21 672 students, respectively. The Chi square test and Logistic regression model were used to analyze the influencing factors of depressive symptoms in middle and high school students. Results: From 2018 to 2021, depressive symptoms detection rate of middle school students was 14.8%, with higher rate in girls (17.1%) than in boys (12.7%), higher rate in high school (17.1% in ordinary high school, 17.6% in vocational high school) than middle school (12.5%)( χ 2=278.77, 327.22, P <0.05). Univariate analysis showed that there were statistically significant differences in depressive symptoms detection rate among middle school students with different years (2018: 16.7%，2019: 17.9% , 2020: 13.1%, 2021: 13.0%), residence (yes: 16.3%, no:13.5%), body mass index classification (not overweight or obesity: 14.8%, overweight: 14.2%, Obesity: 15.7%), weekly exercise days (0-2 d: 17.1%, 3-5 d: 12.5%, 6-7 d: 13.1%) and bullying (yes: 35.5%, no: 10.7%) ( χ 2=293.40, 118.35, 7.83, 287.24, 4 978.84, P <0.05). Multivariate Logistic regression analysis showed that female students, ordinary high schools, vocational high schools, obesity, school bullying were positively correlated with depression ( OR =1.65, 1.70, 1.60, 1.12, 5.21), exercise 3 to 5 days per week, exercise 6 to 7 days per week were negatively correlated with depression ( OR=0.77, 0.81, P <0.01). Conclusions Depressive symptoms among middle and high school students in Zhejiang Province are prominent. Strengthening mental health education for students and providing attention and support from families, schools, and society are essential steps to reduce the occurrence of depressive symptoms among these students.

BACKGROUND:It is of great significance to find new diagnostic markers of the disease and molecular targets for the treatment of the disease and the alleviation of organ injury.Ferroptosis is a newly discovered form of cell death.Overactivation of ferroptosis in animal models of sepsis is associated with the activation of inflammatory response and the injury of the liver,heart,kidney and other important organs,but the relationship between ferroptosis and bloodstream infection is not very clear. OBJECTIVE:To study the changes and biological significance of ferroptosis in a mouse model of blood stream infection induced by different bacteria. METHODS:Blood stream infection models induced by gram negative bacteria Escherichia coli,Klebsiella pneumoniae and gram positive bacteria Staphylococcus aureus and Enterococcus faecalis were established in SPF-grade ICR male mice,with 42 mice in each group.The mRNA expression levels of ferroptosis marker genes transferrin receptor 1 and glutathione peroxidase 4 in the liver,myocardium and kidney were detected at 0.5,1,3,6,12,24 and 48 hours after modeling.Another 18 SPF-grade ICR male mice were selected and randomly divided into dimethyl sulfoxide(DMSO)control group,DMSO+Klebsiella pneumoniae group,and Ferrostatin-1+Klebsiella pneumoniae group,with 6 mice in each group.In the latter two groups,animal models of Klebsiella pneumoniae bloodstream infection were established by tail vein injection of Klebsiella pneumoniae suspension,and 5 mg/kg Ferrostatin-1 and an equal dose of DMSO were given intraperitoneally 1 hour prior to the modeling of bloodstream infection,respectively.Serum levels of alanine aminotransferase,aspartate aminotransferase,blood creatinine,blood urea nitrogen,phosphocreatine kinase isoenzyme,lactate dehydrogenase,and mRNA expression levels of ferroptosis marker genes in various tissues were assayed at 6 hours after modeling. RESULTS AND CONCLUSION:After bloodstream infection modeling,the mRNA expression levels of transferrin receptor 1 in the liver,myocardium and kidney of bloodstream infection mice with different bacteria increased first and then decreased;and the mRNA expression level of glutathione peroxidase 4 decreased first,then increased,and reached the peak at 6 hours after modeling.The changes in transferrin receptor 1 and glutathione peroxidase 4 mRNA levels in bloodstream infection mice induced by gram-negative bacteria were more significant than those in blood stream infection mice induced by gram-positive bacteria,especially in bloodstream infection mice induced by Klebsiella pneumoniae.At 6 hours after bloodstream infection induced by Klebsiella pneumoniae,the levels of alanine aminotransferase,aspartate aminotransferase,serum creatinine,blood urea nitrogen,creatine phosphate kinase isoenzyme,lactate dehydrogenase in mice were significantly increased.Before modeling,Ferrostatin-1 intervention significantly reduced the levels of alanine aminotransferase,aspartate aminotransferase,serum creatinine,blood urea nitrogen,creatine phosphate kinase isoenzyme,and lactate dehydrogenase.All these findings indicate that the activation of ferroptosis in bloodstream infection mice induced by different bacteria is obvious,and the activation of ferroptosis in bloodstream infection mice induced by gram-negative bacteria is more obvious.Inhibition of iron death significantly attenuates liver,myocardial,and kidney injury in the mouse model of bloodstream infection induced by Klebsiella pneumoniae.

Bacterial biofilms gave rise to persistent infections and multi-organ failure, thereby posing a serious threat to human health. Biofilms were formed by cross-linking of hydrophobic extracellular polymeric substances (EPS), such as proteins, polysaccharides, and eDNA, which were synthesized by bacteria themselves after adhesion and colonization on biological surfaces. They had the characteristics of dense structure, high adhesiveness and low drug permeability, and had been found in many human organs or tissues, such as the brain, heart, liver, spleen, lungs, kidneys, gastrointestinal tract, and skeleton. By releasing pro-inflammatory bacterial metabolites including endotoxins, exotoxins and interleukin, biofilms stimulated the body’s immune system to secrete inflammatory factors. These factors triggered local inflammation and chronic infections. Those were the key reason for the failure of traditional clinical drug therapy for infectious diseases.In order to cope with the increasingly severe drug-resistant infections, it was urgent to develop new therapeutic strategies for bacterial-biofilm eradication and anti-bacterial infections. Based on the nanoscale structure and biocompatible activity, nanobiomaterials had the advantages of specific targeting, intelligent delivery, high drug loading and low toxicity, which could realize efficient intervention and precise treatment of drug-resistant bacterial biofilms. This paper highlighted multiple strategies of biofilms eradication based on nanobiomaterials. For example, nanobiomaterials combined with EPS degrading enzymes could be used for targeted hydrolysis of bacterial biofilms, and effectively increased the drug enrichment within biofilms. By loading quorum sensing inhibitors, nanotechnology was also an effective strategy for eradicating bacterial biofilms and recovering the infectious symptoms. Nanobiomaterials could intervene the bacterial metabolism and break the bacterial survival homeostasis by blocking the uptake of nutrients. Moreover, energy-driven micro-nano robotics had shown excellent performance in active delivery and biofilm eradication. Micro-nano robots could penetrate physiological barriers by exogenous or endogenous driving modes such as by biological or chemical methods, ultrasound, and magnetic field, and deliver drugs to the infection sites accurately. Achieving this using conventional drugs was difficult. Overall, the paper described the biological properties and drug-resistant molecular mechanisms of bacterial biofilms, and highlighted therapeutic strategies from different perspectives by nanobiomaterials, such as dispersing bacterial mature biofilms, blocking quorum sensing, inhibiting bacterial metabolism, and energy driving penetration. In addition, we presented the key challenges still faced by nanobiomaterials in combating bacterial biofilm infections. Firstly, the dense structure of EPS caused biofilms spatial heterogeneity and metabolic heterogeneity, which created exacting requirements for the design, construction and preparation process of nanobiomaterials. Secondly, biofilm disruption carried the risk of spread and infection the pathogenic bacteria, which might lead to other infections. Finally, we emphasized the role of nanobiomaterials in the development trends and translational prospects in biofilm treatment.

AIM To study the neoflavonoids from Dalbergia cochinchinensis Pierre ex Laness and their anti-hypoxia/reoxygenation injury activities on H9c2 myocardial cells.METHODS The 70%ethanol extract from D.cochinchinensis was isolated and purified by silica gel,Sephadex LH-20 and reverse-preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.The CCK-8 method was used to detect their activities on H9c2 cells and protective effects on hypoxia-reoxygenation injury of H9c2 cells,and their structure-activity relationship was analyzed.RESULTS Twelve compounds were isolated and identified as latifolin(1),5-O-methyllatifolin(2),mimosifoliol(3),5-O-methydalbergiphenol(4),dalbergiphenol(5),cearoin(6),2,4-dihydroxy-5-methoxy-benzophenone(7),2-hydroxy-4,5-dimethoxybenzophenone(8),melannoin(9),2,2′,5-trihydroxy-4-methoxybenzophenone(10),dalbergin(11),4-methoxydalbergione(12).The dalbergiphenols and dalbergins had little toxicity to H9c2 cells,and dalbergiphenols had strong activity against hypoxia-reoxygenation injury of H9c2 cells.CONCLUSION Compound 8 is a new natural product.Compounds 4,9 are isolated from this plant for the first time.Dalbergiphenols may be the main neoflavonoids against hypoxia-reoxygenation injury of H9c2 cells.

Objective: To describe the prevalence characteristics and trend of malnutrition among primary and secondary school students in Zhejiang Province from 2008 to 2021, so as to provide scientific references for targeted interventions on malnutrition among children and adolescents. Methods: Based on the National Student Common Diseases and Health Influencing Factors Surveillance Project, 81 228 primary and middle school students aged 9-17 from Zhejiang Province were recruited for a questionnaire in 2008, 2014 and 2021, with stratified cluster random sampling method. Malnutrition was determined by Screening for Malnutrition in School aged Children and Adolescents. The Kruskal-Wallis test was used for non normally distributed data, and the Chi square test was used for categorical data. A trend Chi square test analyzed detection rates across different years. Results: The prevalence rates of malnutrition, stunting, mild wasting, and moderate to severe wasting among primary and secondary school students in 2008, 2014 and 2021 were 12.0%, 6.6%, 6.0%; 1.2%, 0.5%, 0.3%; 6.0%, 3.9%, 3.6%; and 4.7%, 2.2%, 2.2%, with an overall declining trend ( χ 2 trend =532.73, 181.43, 161.24, 240.38, P <0.05). The prevalence rates of malnutrition and mild wasting in each year were higher in boys (13.7%, 7.6%; 7.5%, 5.0%; 7.1%, 4.5%) than in girls (10.3%, 4.4%; 5.5%, 2.7%; 4.8%, 2.5%) ( χ 2=54.45, 88.67; 47.04, 81.07; 85.28, 98.81; P <0.01). The difference in malnutrition prevalence between urban and rural areas gradually narrowed (12.5%, 11.6%; 6.9%, 6.3%; 6.0%, 6.0%), with no statistically significant difference in 2021 ( χ 2= 0.01 , P >0.05). Malnutrition among primary and secondary school students was primarily characterized by mild wasting (56.0%) in Zhejiang Province. Compared to 2008, the prevalence of malnutrition in 2014 and 2021 showed a steady upward trend with increasing age in Zhejiang Province( χ 2 trends =44.52, 11.78, P <0.01). Conclusions The prevalence of malnutrition among primary and secondary school students aged 9 to 17 years in Zhejiang Province decreases by year from 2008 to 2021. However, the prevalence increase steadily with age, and boys have a higher prevalence of malnutrition. Policies should be developed age , gender , and growth appropriate dietary patterns to reduce malnutrition among primary and secondary school students.

Objective To assess the nutritional status and dietary quality of medical students and its influencing factors.Methods Students from Shanghai Medicial College of Fudan University were recruited to complete the 7-day and 24-hour dietary records,with food consumption measured by weight.A comprehensive evaluation of the students'dietary quality was carried out by comparing their actual nutrient intake against recommended levels and calculating the component score of the Chinese Healthy Eating Index(CHEI).Factor analysis was used to extract dietary patterns.All subjects were further divided into high score group and low score group based on total CHEI.Binary Logistic regression was used to determine the factors influencing dietary quality.Results The study participants had an average daily energy intake of(2 057.02±501.87)kcal/d,80%from on-campus canteen meals.Carbohydrates,proteins and fats contributed to 48.90%,16.55%and 36.07%of the total energy intake,respectively.The CHEI median score was 67.55.Component scores for tubers,vegetables,fruits,dairy,fish and seafood,and nuts were below 60%,indicating an unbalanced diet.Being in the graduate stage(OR=0.53,95%CI:0.28-0.98)and having unreasonable body weight expectations(OR=0.37,95%CI:0.17-0.81)were associated with lower CHEI scores.Conversely,higher CHEI scores were associated with the fruit-dairy dietary pattern(OR=8.20,95%CI:3.39-19.84),the tuber-vegetable dietary pattern(OR=3.41,95%CI:1.58-7.32),and lower rates of on-campus dining(OR=1.92,95%CI:1.02-3.59).Conclusion The energy intake of students at Shanghai Medical College of Fudan University appears to be adequate.However,a relatively high proportion of energy supply from fat intake indicates a need for improvement in their dietary structure.The dietary quality of students is mainly influenced by their educational level,weight expectations and dietary patterns.

Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5％were gram-positive and 70.5％were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3％,76.7％and 77.9％,respectively.Overall,94.0％of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8％of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2％in the isolates from children and 95.7％in the isolates from adults.The resistance rate to carbapenems was lower than 13.1％in most Enterobacterales species except for Klebsiella,21.7％-23.1％of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1％to 13.3％.The prevalence of meropenem-resistant strains decreased from 23.5％in 2019 to 18.0％in 2022 in Pseudomonas aeruginosa,and decreased from 79.0％in 2019 to 72.5％in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.

Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.