BACKGROUND:Psoralen has a strong anti-osteoporotic activity and may have a restorative effect on chemotherapy-induced osteoporosis. OBJECTIVE:To explore the restorative effect of psoralen on the osteogenic differentiation of bone marrow mesenchymal stem cells in mice inhibited by cyclophosphamide and its mechanism. METHODS:C57BL/6 mouse bone marrow mesenchymal stem cells were isolated and cultured.Effect of psoralen on viability of bone marrow mesenchymal stem cells was detected by MTT assay.Osteogenic induction combined with alkaline phosphatase staining was used to determine the optimal dose of psoralen to restore the osteogenic differentiation of bone marrow mesenchymal stem cells inhibited by cyclophosphamide.The mRNA expression levels of Runx2,alkaline phosphatase,Osteocalcin,osteoprotegerin,and Wnt/β-catenin signaling pathway-related genes Wnt1,Wnt4,Wnt10b,β-catenin,and c-MYC were measured by RT-qPCR at different time points under the intervention with psoralen.The protein expression of osteogenic specific transcription factor Runx2 and Wnt/β-catenin signaling pathway related genes Active β-catenin,DKK1,c-MYC,and Cyclin D1 was determined by western blot assay at different time points under the intervention with psoralen. RESULTS AND CONCLUSION:(1)There was no significant effect of different concentrations of psoralen on the viability of bone marrow mesenchymal stem cells.The best recovery of the inhibition of osteogenic differentiation of bone marrow mesenchymal stem cells caused by cyclophosphamide was under the intervention of psoralen at a concentration of 200 μmol/L.(2)Psoralen reversed the reduction in osteogenic differentiation marker genes Runx2,alkaline phosphatase,Osteocalcin and osteoprotegerin mRNA expression and Runx2 protein expression in bone marrow mesenchymal stem cells caused by cyclophosphamide conditioned medium.(3)Psoralen reversed the decrease in Wnt/β-catenin pathway-related genes Wnt4,β-catenin,c-MYC mRNA and Active β-catenin,c-MYC,and Cyclin D1 protein expression and the increase in DKK1 protein expression in bone marrow mesenchymal stem cells caused by cyclophosphamide conditioned medium.(4)The results showed that cyclophosphamide inhibited osteogenic differentiation of bone marrow mesenchymal stem cells in mice,and psoralen had a restorative effect on it.The best intervention effect was achieved at a concentration of 200 μmol/L psoralen,and this protective effect might be related to the activation of Wnt4/β-catenin signaling pathway by psoralen.

Objective To analyze the seroepidemiology characteristics of Epstein-Barr virus(EBV)infection in children in Shenyang.Methods From June 2022 to May 2023,serum was collected from 12 083 children at Shengjing hospital of China Medical University.Serum capsid antigen(VCA)-IgM,VCA-IgG,EBV nuclear antigen-IgG(EBNA-IgG),and early antigen-IgG(EA-IgG)antibodies were detected using the LIAISION chemiluminescence immunoassay.EBV-DNA was detected using real-time PCR.Differences in antibody positivity rates between sexes,ages,and seasons of onset were compared.Results In 12 083 patients,the positive rates of VCA-IgM,VCA-IgG,EBNA-IgG,and EA-IgG were 9.95％(1 202/12 083),50.57％(6 110/12 083),46.03％(5 562/12 083)and 4.93％(596/12 083).The positive rates of VCA-IgM and EA-IgG were lower in male patients(9.09％and 4.44％,respectively)than in female patients(11.10％,5.60％;all P＜0.05).The differences in the positive rates for VCA-IgM,VCA-IgG,EBNA-IgG,and EA-IgG antibodies in children of different ages were statistically significant(all P＜0.05).Differences in the positive rates of VCA-IgG,EBNA-IgG,and EA-IgG antibodies were statistically significant when compared between seasons(all P＜0.05).Fourteen EBV antibody-positive combinations were detected,of which the main combination was VCA-IgG and EBNA-IgG double-positive,with a total of 4 741 cases(39.24％).Of the 3 712 children who underwent EBV-DNA detection testing,3 034(81.73％)were EBV-DNA-negative and 678(18.27％)were EBV-DNA-posi-tive.VCA-IgG and EBNA-IgG double positivity was the most common in EBV-DNA-negative and EBV-DNA-positive children,accounting for 983(26.48％)and 194 cases(5.23％),respectively.Conclusion Both VCA-IgG and EBNA-IgG antibodies are main positive in children with EBV infection in Shenyang.The positive rate of EBV antibodies is lower in boys than in girls.The positive rates of EBV anti-bodies differ in children of different ages and seasons of onset.

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.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.

Objective To understand the changing distribution and antimicrobial resistance profiles of Klebsiella strains in 52 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Antimicrobial susceptibility testing was carried out according to the unified CHINET protocol.The susceptibility results were interpreted according to the breakpoints in the Clinical & Laboratory Standards Institute(CLSI)M100 document.Results A total of 241,549 nonduplicate Klebsiella strains were isolated from 2015 to 2021,including Klebsiella pneumoniae(88.0％),Klebsiella aerogenes(5.8％),Klebsiella oxytoca(5.7％),and other Klebsiella species(0.6％).Klebsiella strains were mainly isolated from respiratory tract(48.49±5.32)％.Internal medicine(22.79±3.28)％,surgery(17.98±3.10)％,and ICU(14.03±1.39)％were the top 3 departments where Klebsiella strains were most frequently isolated.K.pneumoniae isolates showed higher resistance rate to most antimicrobial agents compared to other Klebsiella species.Klebsiella isolates maintained low resistance rates to tigecycline and polymyxin B.ESBLs-producing K.pneumoniae and K.oxytoca strains showed higher resistance rates to all the antimicrobial agents tested compared to the corresponding ESBLs-nonproducing strains.The K.pneumoniae and carbapenem-resistant K.pneumoniae(CRKP)strains isolated from ICU patients demonstrated higher resistance rates to majority of the antimicrobial agents tested than the strains isolated from non-ICU patients.The CRKP strains isolated from adult patients had higher resistance rates to most of the antimicrobial agents tested than the corresponding CRKP strains isolated from paediatric patients.Conclusions The prevalence of carbapenem-resistant strains in Klebsiella isolates increased greatly from 2015 to 2021.However,the Klebsiella isolates remained highly susceptible to tigecycline and polymyxin B.Antimicrobial resistance surveillance should still be strengthened for Klebsiella strains.

Objective To investigate the changing distribution and antibiotic resistance profiles of clinical isolates of Staphylococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Staphylococcus according to the unified protocol of CHINET(China Antimicrobial Surveillance Network)using disk diffusion method and commercial automated systems.The CHINET antimicrobial resistance surveillance data from 2015 to 2021 were interpreted according to the 2021 CLSI breakpoints and analyzed using WHONET 5.6.Results During the period from 2015 to 2021,a total of 204,771 nonduplicate strains of Staphylococcus were isolated,including 136,731(66.8％)strains of Staphylococcus aureus and 68,040(33.2％)strains of coagulase-negative Staphylococcus(CNS).The proportions of S.aureus isolates and CNS isolates did not show significant change.S.aureus strains were mainly isolated from respiratory specimens(38.9±5.1)％,wound,pus and secretions(33.6±4.2)％,and blood(11.9±1.5)％.The CNS strains were predominantly isolated from blood(73.6±4.2)％,cerebrospinal fluid(12.1±2.5)％,and pleural effusion and ascites(8.4±2.1)％.S.aureus strains were mainly isolated from the patients in ICU(17.0±7.3)％,outpatient and emergency(11.6±1.7)％,and department of surgery(11.2±0.9)％,whereas CNS strains were primarily isolated from the patients in ICU(32.2±9.7)％,outpatient and emergency(12.8±4.7)％,and department of internal medicine(11.2±1.9)％.The prevalence of methicillin-resistant strains was 32.9％in S.aureus(MRSA)and 74.1％in CNS(MRCNS).Over the 7-year period,the prevalence of MRSA decreased from 42.1％to 29.2％,and the prevalence of MRCNS decreased from 82.1％to 68.2％.MRSA showed higher resistance rates to all the antimicrobial agents tested except trimethoprim-sulfamethoxazole than methicillin-susceptible S.aureus(MSSA).Over the 7-year period,MRSA strains showed decreasing resistance rates to gentamicin,rifampicin,and levofloxacin,MRCNS showed decreasing resistance rates to gentamicin,erythromycin,rifampicin,and trimethoprim-sulfamethoxazole,but increasing resistance rate to levofloxacin.No vancomycin-resistant strains were detected.The prevalence of linezolid-resistant MRCNS increased from 0.2％to 2.3％over the 7-year period.Conclusions Staphylococcus remains the major pathogen among gram-positive bacteria.MRSA and MRCNS were still the principal antibiotic-resistant gram-positive bacteria.No S.aureus isolates were found resistant to vancomycin or linezolid,but linezolid-resistant strains have been detected in MRCNS isolates,which is an issue of concern.

Objective:To understand the epidemiological and etiological characteristics of hand-foot-mouth disease (HFMD) in the Nanshan District of Shenzhen City from 2019 to 2022 and to provide a scientific basis for HFMD prevention in the area.Methods:Epidemiological data on HFMD in Shenzhen Nanshan District from 2019 to 2022 in the China Information System for Disease Control and Prevention were analyzed using descriptive research methods.Real-time reverse transcription polymerase chain reaction (RT-PCR) was used to analyze the etiology characteristics of clinical specimens from HFMD patients. The VP1 gene of the dominant pathogen coxsackievirus A6 (CV-A6) was amplified and sequenced. SepMan Pro of DNASTAR software was used for sequence assembly and MegAlign was used for nucleotide homology analysis.Results:A total of 13 195 HFMD cases were reported in Shenzhen Nanshan District from 2019 to 2022, with an average annual incidence rate of 186.18/100, 000. Summer and autumn are the main onset seasons and children under 7 years old were the main population, accounting for 93.1%. The male-to-female ratio is 1.44∶1. A total of 451 clinical HFMD specimens were detected in the laboratory, including 403 positive (87.36%) and 48 negative (10.64%). The main pathogens were CV-A6 (63.03%), coxsackievirus A16 (CV-A16) (27.79%), coxsackievirus A4 (CV-A4) (4.71%), coxsackievirus A10 (CV-A10) (1.99%), Echovirus 11 (Echo-11) (0.25%), and uncertain type accounted for 2.23%, with no detection for enterovirus71 (EV71) type. The nucleotide homology of the 13 CV-A6 strains ranged from 94.0%?99.6%, and the nucleotide homology with the prototype strain Gdula ranged 84.1%?85.8%. The results of phylogenetic tree showed that all 13 CV-A6 strains in Nanshan District were of the D3a genotype.Conclusions:FHFMD in Nanshan District of Shenzhen City in 2019-2022 shows obvious differences in population and time distribution. Therefore, it is necessary to strengthen publicity and education on HFMD prevention and control in the summer and fall seasons and among key populations. CV-A6 and CV-A16 are the dominant strains of HFMD in Nanshan District, Shenzhen in recent years, so the monitoring of the dominant strains should be improved.

ObjectiveTo study the traditional Chinese medicine （TCM） syndromes of children with alopecia areata， and provide evidence for TCM differentiation and treatment in clinic. MethodsA retrospective analysis was conducted on the clinical data of 800 children with alopecia areata admitted to the Hair Medicine Center of the China-Japan Friendship Hospital from January 1， 2012 to December 31， 2021. The clinical data of the children were collected using a four-examination information questionnaire， including clinical characteristics （age of consultation， age of onset， course of disease， family history， severity grading）， alopecia areata-related factors （triggers）， and four-examination information （including sleep， diet， emotions， bladder and bowel function， etc.）. Descriptive frequency analyses， rank sum tests， factor analyses and cluster analyses were performed， and the distribution of the major TCM syndromes was summarised with the clinical data. ResultsThere were 800 children with alopecia areata， including 449 males and 351 females； 8 cases （1.00%） were in infancy， 36 cases （4.50%） were in early childhood， 180 cases （22.50%） were in preschool， 380 cases （47.50%） were in school age， and 196 cases （24.50%） were in puberty at the time of consultation； the average age of consultation was 8.31±3.86 years， the average age of onset of disease was 5.40±3.82 years， and the average duration of disease was 2.94±2.77 years； 527 children （65.87%） with severe alopecia areata； 85 children （13.56%） had a family history of alopecia areata； 772 children （96.50%） had unknown triggers for their first alopecia areata， and 28 children （3.50%） reported the presence of obvious triggers， including fright （9 cases）， high fever （5 cases）， allergic reactions （4 cases）， micronutrient （zinc， iron， etc.） deficiencies （4 cases）， inappropriate diet （2 cases）， environmental factors （1 case， new house renovation）， atopic dermatitis （1 case）， atopic asthma （1 case）， and pneumonia （1 case）. A total of 40 four-examination information items were collected， among which the frequency of kicking quilts was the highest with 380 cases （47.50%）， followed by picky eating （369 cases， 46.13%）， sleeplessness （334 cases， 41.75%）， irritability （334 cases， 41.75%）， partiality towards certain foods （306 cases， 38.25%）， impulsiveness （297 cases， 37.13%）， dry stools （233 cases， 29.13%）， yellow urine （215 cases， 26.88%）， nail biting （213 cases， 26.63%）， bad breath （211 cases， 26.38%）. According to factor analysis and cluster analysis， five types of TCM syndromes were obtained， in order as qi and blood deficiency syndrome （110 cases， 13.75%）， spleen deficiency syndrome （114 cases， 14.25%）， kidney essence deficiency syndrome （140 cases， 17.50%）， dietary stagnation syndrome （150 cases， 18.75%）， and liver depression and spleen deficiency syndrome （286 cases， 35.75%）. Patients in each age group and SALT grading are mainly liver depression and spleen deficiency syndrome. ConclusionThe TCM symptoms of children with alopecia areata are mainly based on qi and blood deficiency syndrome， spleen deficiency syndrome， kidney essence deficiency syndrome， dietary stagnation syndrome， and liver depression and spleen deficiency syndrome， of which liver depression and spleen deficiency syndrome is the most common type at different ages and stages of the disease.