BACKGROUND:Magnetic nanomaterials have biological activities such as promoting osteogenic differentiation of stem cells and inhibiting osteoclast formation,and can effectively promote the healing of injured bone tissue under the synergistic effect of magnetic fields.They have a very broad application prospect in bone injury repair. OBJECTIVE:To review the mechanism of magnetic nanomaterials and magnetic fields promoting bone repair,as well as their research progress in the field of bone injury repair. METHODS:Relevant literature search was conducted in PubMed and Web of Science databases with the search terms"magnetic nanomaterials,magnetic field,bone repair,bone tissue engineering,stem cell,osteoblast,osteoclast."The time limit of literature search was from 2003 to 2023,which was screened and analyzed.Some classic articles were manually retrieved,and 98 articles were finally included for analysis. RESULTS AND CONCLUSION:(1)Magnetic nanomaterials have biological effects such as promoting osteoblast differentiation,inhibiting osteoclast formation and regulating the immune microenvironment.In addition,magnetic nanomaterials can regulate the physicochemical properties of tissue engineering scaffolds,such as mechanical properties and surface morphology,and endowed with magnetic properties,which is conducive to the regulation of the adhesion,proliferation and osteogenic differentiation of stem cells.(2)The magnetic field has the ability to regulate multiple cell signaling pathways to promote osteoblast differentiation,inhibit osteoclast formation,stimulate angiogenesis and other biological effects,thus accelerating the healing of damaged bone tissue.(3)The joint application of magnetic nanomaterials and magnetic field accelerates the repair of bone damage by activating mechanotransduction,increasing the content of intracellular magnetic nanoparticles,and enhancing the effect of micro-magnetic field,which provides a new idea for the research of bone tissue engineering.(4)Magnetic field has demonstrated definite efficacy in the treatment of clinical fractures,osteoporosis,and osteoarthritis diseases,which is beneficial for bone tissue growth,reducing bone loss,alleviating pain,and improving the quality of life of patients.(5)Magnetic nanomaterials and magnetic fields have great potential for application in bone damage repair and regeneration,but the interaction mechanism between magnetic nanomaterials,magnetic fields,and cells has not been fully elucidated.Moreover,the key parameters of magnetic fields that regulate intracellular molecular events,including the type,intensity,frequency,duration,and mode of the magnetic field,as well as the precise biological effects of a specific magnetic field on osteoblasts and the underlying mechanisms,have yet to be defined.(6)Further attention needs to be paid to the effects on osteoclasts,nerves,blood vessels,and immune cells in the microenvironment of damaged tissues.Finally,the safety of magnetic materials for human use is yet to be systematically studied in terms of their distribution,metabolism,and acute and chronic toxicities.

Aim To analyze serum exosome sequencing data from patients with coronary heart disease(CHD)and normal subjects by using bioinformatics-related methods to construct a competitive endogenous ln-cRNA-miRNA-mRNA(ceRNA)regulatory network,to mine the predicted potential Chinese medicines,and to perform preliminary validation of the biological processes and core Chinese medicines involved in the ceRNA network.Methods We used exoRbase data-base to obtain the expression matrix of differential genes,combined with the raw letter method to con-struct the ceRNA network,and performed GO analysis and KEGG analysis on the differential mRNAs in the network,and used COREMINE database to predict the biological processes and core target genes involved in the ceRNA network,and to screen the herbal medi-cines with potential therapeutic effects;AVECs oxida-tive damage cell model was constructed in vitro,and the cytoskeleton,tube-forming function,cell prolifera-tion,LDH leakage rate,ROS level and p-AKT,AKT,p-PI3K and AKT protein expression were examined to verify the action pathways and targets of the core Chi-nese medicine Salvia miltiorrhiza for the treatment of coronary heart disease.Results Compared with nor-mal subjects,395 mRNAs,80 miRNAs,60 lncRNA differential genes,and 80 miRNAs were predicted in serum exosomes of coronary heart disease,and the constructed ceRNA sub-network,mainly consisted of 21 lncRNAs,80 miRNAs,and 82 mRNAs;AKT1,VEGFA,IL1B and other genes in the network.The abnormally expressed mRNAs were involved in biologi-cal processes such as oxidative stress and signaling pathways such as PI3 K/Akt,and Dan Shen,Chuanx-iong and Panax notoginseng were most closely related to exosome-mediated biological processes and core genes in coronary heart disease.The active ingredients of tanshinone ⅡA,the core Chinese medicine,could pro-mote vascular endothelial cell proliferation,tube for-mation,skeleton formation and repair,reduce LDH leakage rate and ROS level,and promote the expres-sion of p-AKT and p-PI3K protein.Conclusion There is a complex ceRNA regulatory network trans-duction in coronary artery disease serum exosomes,and traditional Chinese medicine can be used to treat CHD through multi-target intervention,and Dan Shen,Chuanxiong and Panax notoginseng are expected to be candidate sources of traditional Chinese medicine,a-mong which the active ingredient of Dan Shen,tanshi-none ⅡA,activates PI3 K/Akt signaling pathway to play a protective role against oxidative stress-injured cells,and treats CHD.

Objective To explore early postoperative gait characteristics and clinical outcomes after total knee arthroplasty(TKA).Methods From February 2023 to July 2023,26 patients with unilateral knee osteoarthritis(KOA)were treated with TKA,including 4 males and 22 females,aged from 57 to 85 years old with an average of(67.58±6.49)years old;body mass in-dex(BMI)ranged from 18.83 to 38.28 kg·m-2 with an average of(26.43±4.15)kg·m-2;14 patients on the left side,12 pa-tients on the right side;according to Kellgren-Lawrence(K-L)classification,6 patients with grade Ⅲ and 20 patients with grade Ⅳ;the courses of disease ranged from 1 to 14 years with an average of(5.54±3.29)years.Images and videos of standing up and walking,walking side shot,squatting and supine kneeling were taken with smart phones before operation and 6 weeks after operation.The human posture estimation framework OpenPose were used to analyze stride frequency,step length,step length,step speed,active knee knee bending angle,stride length,double support phase time,as well as maximum hip flexion angle and maximum knee bending angle on squatting position.Western Ontario and McMaster Universities(WOMAC)arthritis index and Knee Society Score(KSS)were used to evaluate clinical efficacy of knee joint.Results All patients were followed up for 5 to 7 weeks with an average of(6.00±0.57)weeks.The total score of WOMAC decreased from(64.85±11.54)before op-eration to(45.81±7.91)at 6 weeks after operation(P＜0.001).The total KSS was increased from(101.19±9.58)before opera-tion to(125.50±10.32)at 6 weeks after operation(P＜0.001).The gait speed,stride frequency and stride length of the affected side before operation were(0.32±0.10)m·s-1,(96.35±24.18)steps·min-1,(0.72±0.14)m,respectively;and increased to(0.48±0.11)m·s 1,(104.20±22.53)steps·min-1,(0.79±0.10)m at 6 weeks after operation(P＜0.05).The lower limb support time and active knee bending angle decreased from(0.31±0.38)sand(125.21±11.64)° before operation to(0.11±0.04)s and(120.01±13.35)° at 6 weeks after operation(P＜0.05).Eleven patients could able to complete squat before operation,13 patients could able to complete at 6 weeks after operation,and 9 patients could able to complete both before operation and 6 weeks after operation.In 9 patients,the maximum bending angle of crouching position was increased from 76.29° to 124.11° before operation to 91.35° to 134.12° at 6 weeks after operation,and the maximum bending angle of hip was increased from 103.70° to 147.25° before operation to 118.61° to 149.48° at 6 weeks after operation.Conclusion Gait analysis technology based on artificial intelligence image recognition is a safe and effective method to quantitatively identify the changes of pa-tients'gait.Knee pain of KOA was relieved and the function was improved,the supporting ability of the affected limb was im-proved after TKA,and the patient's stride frequency,stride length and stride speed were improved,and the overall movement rhythm of both lower limbs are more coordinated.

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 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 evaluate the effect of low-dose recombinant interleukin-2(rIL-2)therapy on immunocyte subsets and its side effects in children with solid tumor.Methods:A total of 22 children(11 males and 11 females)with solid tumor in our department from December 2012 to November 2017 were selected,with a median age of 9(3-16)years old when starting IL-2 therapy.ALL surgeries and chemotherapy of children had been completed before low-dose rIL-2 therapy,and 17 cases achieved complete remission(CR)and 5 cases achieved partial remission(PR).A low-dose rIL-2 therapy was given 1 month after chemotherapy for 1 year:4 × 105 IU/(m2·d),s.c.for every other day,3 times per week.The immunocyte subsets were detected every 3 months until the end of treatment,meanwhile,disease condition and therapy-related side effects were followed up.Results:After low-dose rIL-2 therapy in 22 children,the absolute values of CD3+T cells,CD3-CD56+natural killer cells,CD3+CD4+helper T cells(Th)and CD3+CD8+cytotoxic T cells were up-regulated remarkably,as well as Th/suppressor T cells(all P＜0.05).While,there were no significant differences in absolute value and proportion of CD4+CD25+CD127-Treg cells during therapy.Among the 17 children who achieved CR before rIL-2 therapy,14 cases continued to maintain CR after therapy,while 3 cases relapsed,and with 2 died after treatment abandonment.The 5 children who achieved PR before low-dose rIL-2 therapy were evaluated CR by PET/CT scan after treatment.In the early stage of low-dose rIL-2 therapy,1 child developed skin rashes at the injection sites,and 2 children ran a slight to mild transient fever.Their symptoms disappeared without any organ damage after symptomatic treatment.Conclusion:Low-dose rIL-2 therapy has good drug tolerance,and changes the distribution of anti-tumor immune-cell subgroup in peripheral blood of children with solid tumor remarkably without up-regulation of absolute value and ratio of Treg cells.

Objective:To evaluate the gene mutation profile and prognostic significance of adult cytogenetically normal acute myeloid leukemia (CN-AML) with CEBPA-bZIP mutation. Methods:Targeted sequencing was implemented on the diagnostic bone marrow DNA samples of 141 adult CN-AML subjects with CEBPA-bZIP mutation. The nomogram model for leukemia-free survival (LFS) rate was generated by combining genetic abnormalities and clinical data. Risk stratification was conducted based on prognostic variables and the effect of risk-adjusted consolidation therapy was investigated by Kaplan-Meier method. Results:Four variables were finally included in our nomogram model after multivariate Cox analysis,and an equation for risk score calculation was obtained,risk score=1.3002×white blood cell (WBC) (≥18.77×109/L)+1.4065×CSF3R mutation positive+2.6489×KMT2A mutation positive+1.0128×DNA methylation-related genes mutation positive. According to the nomogram model,patients were further divided into low-risk group (score=0,n=46) and high-risk group (score>0,n=95). Prognostic analysis showed that the 5-year LFS rate,5-year overall survival (OS) rate,and 5-year cumulative incidence of relapse (CIR) of patients who received allogeneic hematopoietic stem cell transplantation (allo-HSCT) in the high-risk group were 93.5％,97.1％,and 3.5％,while those in patients who received maintenance chemotherapy were 32.9％,70.5％,and 63.4％,respectively. The differences were statistically significant (all P<0.05). Allo-HSCT could significantly improve the prognosis of patients in high-risk group. However,no corresponding benefit was observed in the low-risk group. Conclusion:Adult CN-AML with CEBPA-bZIP mutation has a complex co-mutation pattern. The nomogram model based on mutations of CFS3R,KMT2A and DNA methylation-related genes together with WBC count can further divide this subset of patients into a relatively low-risk group and a relatively high-risk group. For individuals in the high-risk group,allo-HSCT is proposed as post-remission therapy. The above data will benefit the prognosis estimation and treatment decision for adult CN-AML with CEBPA-bZIP mutation.

Objective:To develop and evaluate a nomogram prediction model for the 3-month mortality risk of patients with sepsis-associated acute kidney injury (S-AKI).Methods:Based on the American Medical Information Mart for Intensive Care-Ⅳ (MIMIC-Ⅳ), clinical data of S-AKI patients from 2008 to 2021 were collected.Initially, 58 relevant predictive factors were included, with all-cause mortality within 3 months as the outcome event. The data were divided into training and testing sets at a 7∶3 ratio. In the training set, univariate Logistic regression analysis was used for preliminary variable screening. Multicollinearity analysis, Lasso regression, and random forest algorithm were employed for variable selection, combined with the clinical application value of variables, to establish a multivariable Logistic regression model, visualized using a nomogram. In the testing set, the predictive value of the model was evaluated through internal validation. The receiver operator characteristic curve (ROC curve) was drawn, and the area under the curve (AUC) was calculated to evaluate the discrimination of nomogram model and Oxford acute severity of illness score (OASIS), sequential organ failure assessment (SOFA), and systemic inflammatory response syndrome score (SIRS). The calibration curve was used to evaluate the calibration, and decision curve analysis (DCA) was performed to assess the net benefit at different probability thresholds.Results:Based on the survival status at 3 months after diagnosis, patients were divided into 7?768 (68.54%) survivors and 3?566 (31.46%) death. In the training set, after multiple screenings, 7 variables were finally included in the nomogram model: Logistic organ dysfunction system (LODS), Charlson comorbidity index, urine output, international normalized ratio (INR), respiratory support mode, blood urea nitrogen, and age. Internal validation in the testing set showed that the AUC of nomogram model was 0.81 [95% confidence interval (95% CI) was 0.80-0.82], higher than the OASIS score's 0.70 (95% CI was 0.69-0.71) and significantly higher than the SOFA score's 0.57 (95% CI was 0.56-0.58) and SIRS score's 0.56 (95% CI was 0.55-0.57), indicating good discrimination. The calibration curve demonstrated that the nomogram model's calibration was better than the OASIS, SOFA, and SIRS scores. The DCA curve suggested that the nomogram model's clinical net benefit was better than the OASIS, SOFA, and SIRS scores at different probability thresholds. Conclusions:A nomogram prediction model for the 3-month mortality risk of S-AKI patients, based on clinical big data from MIMIC-Ⅳ and including seven variables, demonstrates good discriminative ability and calibration, providing an effective new tool for assessing the prognosis of S-AKI patients.

AIM To study the chemical constituents from the n-butanol fraction of Siegesbeckiae glabrescens Makino.METHODS The n-butanol fraction from S.glabrescens was isolated and purified by silica gel,ODS and preparative HPLC,then the structures of obtained compounds were identified by physicochemical properties and spectral data.RESULTS Seventeen compounds were isolated and identified as orientalin B(1),ent-2-oxo-15,16,19-trihydroxypimar-8(14)-ene(2),ent-12α,16-epoxy-2β,15α,19-trihydroxypimar-8-ene(3),ent-12α,16-epoxy-2β,15α,19-trihydroxy-pimar-8(14)-ene(4),kirenol(5),benzyl-O-β-D-glucopyranoside(6),hexyl-β-glucopyranoside(7),(Z)-3-hexenyl-β-D-glucopyranoside(8),phenylethyl-O-β-D-glucopyranoside(9),(6R,9S)-3-oxo-α-ionol-β-D-glucopyranoside(10),2-methoxy-4-(2-propenyl)phenyl-β-D-glucoside(11),4-allyl-2,6-dimethoxyphenyl glucoside(12),2-hydroxy-methylphenyl-1-O-β-D-glucopyranoside(13),icarside B2(14),everlastoside D(15),(2S,4R,5S,7S,9S,10R,13S,15R)-2,7,15,16,19-pentahydroxypimar-8(14)-ene(16),and benzyl-β-D-apiofuranosyl-(1″→6′)-β-D-glucopy-ranoside(17).Compound 9 showed weak ABTS radical scavenging capability,and compound 15 had strong DPPH and ABTS radicals scavenging activities.CONCLUSION Compounds 7-9,14-15 are isolated from genus Siegesbeckia for the first time.Compounds 2-4,7-17 are first isolated from this plant.Compound 9 and 15 exhibit antioxidant activities.

Objective To explore the current status of H.pylori infection in the natural population of Sanya City,analyze its influencing factors,and provide a reference basis for the prevention and control of H.pylori infection.Methods A total of 677 residents from four districts of Sanya City were selected by overall stratified random sampling method,and were subjected to urea 14C breath test and questionnaire survey to calculate the positive rate of H.pylori in the natural population and analyze the influencing factors of H.pylori infection.Results A total of 606 residents were included,and the number of H.pylori positive detections was 261,with a positive detection rate of 38.5％.Among them,different ethnicity,marital status,smoking,eating vegetables and fruits,and literacy level were associated with H.pylori infection(P＜0.05);gender,age,BMI,alcohol consumption,drinking water source,betel quid chewing,and the number of cohabitants were not significantly associated with H.pylori infection(P＞0.05).Family infection was an independent risk factor for H.pylori infection in the natural population of Sanya City,and Li ethnicity,frequent consumption of fruits and vegetables,and college and higher education level were independent protective factors for H.pylori infection in the natural population of Sanya City.Conclusion The rate of H.pylori infection in the natural population of Sanya City is lower than the national average.Consuming more fruits and vegetables and improving the awareness of hygiene protection are conducive to the prevention of H.pylori infection;and the promotion of the family and related members with the same examination and treatment is important to avoid aggregation of infection within the family.