Objective To analyze the anatomical relationship between maxillary premolars and the alveolar bone and maxillary sinus using cone-beam computed tomography(CBCT),in order to provide an anatomical basis for immediate implant placement in maxillary premolars.Methods Data from 351 patients who underwent maxillary CBCT imaging at Yancheng Stomatological Hospital between January 2022 and December 2023 were collected.Measurements included the vertical distance between premolar roots and the maxillary sinus floor,intraosseous root length,angle between the tooth axis and alveolar bone axis,and buccal/palatal bone wall thickness,with comparisons of gender differences.Results The median vertical distance between single-rooted maxillary first premolars and the maxil-lary sinus floor was 10.16 mm,while that for second premolars was 4.61 mm.For double-rooted first premolars,the buccal root dis-tance was(4.13±3.99)mm and the palatal root was(5.14±3.94)mm.Maxillary first premolars were farther from the maxillary sinus floor than maxillary second premolars,with palatal roots farther than buccal roots.The intraosseous root length of maxillary first premo-lars was(9.20±1.44)mum,and maxillary second premolars(9.64±2.04)mm.Maxillary first premolars exhibited significantly shorter intraosseous root length than maxillary second premolars.The angle α between tooth axis and alveolar bone axis was 18.89°±6.33° for maxillary first premolars,and 12.65°±6.10° for maxillary second premolars,showing statistically significant differences.The buccal bone wall thickness of maxillary first premolars gradually decreased from 2 mm subcrest to the apex,while palatal bone walls of maxil-lary first premolars and both buccal/palatal walls of maxillary second premolars progressively thickened from 2 mm subcrest to the apex.Significant correlations were identified between angle α and buccopalatal bone wall thickness at mid-root and the apex:increased α cor-responded with reduced buccal wall thickness and enhanced palatal wall thickness.Conclusion The apical region of maxillary first premolars provides sufficient bone volume for primary stability in immediate implantation,though the thin buccal bone wall necessitates careful consideration of implant shape and positioning.Maxillary second premolar roots are closely adjacent to the maxillary sinus floor,requiring implant stabilization with the sinus floor cortical bone or me-siodistal walls of the extraction socket.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Severe fever with thrombocytopenia syndrome(SFTS)is an acute infectious disease caused by the Dabie Banda-virus(DBV),with a high mortality rate.The annually reported number of cases is steadily increasing.DBV is transmitted pri-marily by tick bites,and its epidemic range is gradually expanding with the spread of its vector,thus posing a serious threat to human health.No licensed preventive vaccine is currently available.The World Health Organization has listed SFTS as an infec-tious disease requiring further investigation of vaccines and treatments with high priority.This article reviews current research progress in SFTS vaccines,to provide a reference for the development of DBV vaccines.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Objective To explore the factors for chemotherapy-induced nausea and vomiting(CINV)in patients with advanced colorectal cancer receiving moderately emetic chemotherapy regimens.Methods 296 patients with colorectal cancer treated with oxaliplatin/irinotecan combination therapy and standard antiemetic prophylaxis regimen at the First Hospital of Jiaxing from July 1,2022 to June 30,2024 were selected,including 164 patients in oxaliplatin combination therapy group and 132 patients in irinotecan combination therapy group.Evaluated the nausea and vomiting status of patients within 5 days after the start of chemotherapy.Analyzed demographic data,medical history data,follow-up data.Results The incidence of CINV in oxaliplatin combination therapy group was 61.59％,and that in irinotecan combination therapy group was 53.79％.The incidence of delayed CINV and severe acute CINV in oxaliplatin combination therapy group were significantly higher than those in irinotecan combination therapy group(P＜0.05).Multivariate analysis showed that the risk factors for acute CINV in the oxaliplatin-based combination regimen were smoking history and CINV history.The risk factors for delayed CINV were age,no history of drinking,history of pregnancy-induced vomiting,motion sickness history,CINV history,and first use of the regimen.For the irinotecan-based combination regimen,the risk factors for acute CINV were motion sickness history and CINV history.The risk factors for delayed CINV were CINV history and anxious emotions.Conclusion When useing standard anti-emetic prophylaxis that still have a high incidence of CINV by moderate emetic chemotherapy drugs in advanced colorectal cancer patients.Patients with high risk factors should actively take preventive measures to control CINV.

Objective:To investigate the biomechanical correlation between ankle instability and osteochondral lesions of the talus (OLT) under loading conditionsMethods:A healthy 29-year-old male volunteer was selected for the study. A 64-slice spiral CT scan of the right lower limb was performed to construct a detailed finite element model of the ankle joint, including ligaments and cartilage. Three injury models were created: models of distal tibiofibular syndesmosis injury, lateral collateral ligament injury, and a combined injury of the distal tibiofibular syndesmosis and lateral collateral ligament. Differences in stress distribution on the tibiotalar joint surface, talus stress, and talus displacement were analyzed through anterior drawer test, inversion stress test, and external rotation stress test.Results:In the anterior drawer test, as the forward traction force increased (40, 60, 80, 100, 120, 140, and 150 N), all the injury models showed a progressive increase in tibiotalar joint surface stress, talus stress, and talus displacement. The combined injury model showed the highest tibiotalar joint surface stress (32.6 MPa), while the lateral collateral ligament injury model demonstrated the highest talus stress (56.5 MPa). Talus displacement increased significantly with traction, reaching the maximum (4.88 mm) in the combined injury model under 150 N. In the inversion stress test, stress on the tibiotalar joint surface in the lateral collateral ligament injury model was concentrated on the posterior-lateral and posterior-medial regions, whereas in the combined injury model, stress on the tibiotalar joint surface was predominantly concentrated in the posterior-medial region. Talus stress was localized to the talus neck and body in all the models, with the combined injury model showing the largest talus displacement (8.46 mm). In the external rotation stress test, stress on the tibiotalar joint surface was mainly distributed in the posterior-medial, posterior-lateral, and anterior-lateral regions in all the models. Talus stress was concentrated at the talus neck and body. The combined injury model exhibited the greatest talus displacement (12.50 mm).Conclusion:Ankle instability, particularly from combined injuries of the distal tibiofibular syndesmosis and lateral collateral ligament, significantly increases the stress concentration and talus displacement under loading conditions, thus elevating the risk of OLT.

Nonunion of osteoporotic vertebral fractures (OVF), predominantly affecting the elderly, can lead to intractable pain, vertebral collapse, progressive kyphotic deformity, and neurological impairment, significantly compromising patients′ quality of life. There exists considerable debate on diagnosis and management of OVF, encompassing key issues such as clinical diagnosis and staging criteria for nonunion, surgical indications and procedure selection, and postoperative rehabilitation planning. Currently, there lacks standardized clinical guideline and expert consensus on the diagnosis and management of OVF nonunion in China. To address this gap, Minimally Invasive Surgery Group of Chinese Orthopedic Association, Osteoporosis Committee of Chinese Association of Orthopedic Surgeons, Prevention and Rehabilitation Committee for Osteoporosis of Chinese Association of Rehabilitation Medicine and Minimally Invasive Orthopedic Surgery Branch of China Association for Geriatric Care jointly organized domestic experts in spinal surgery, endocrinology, and rehabilitation to formulate the Clinical guideline for the diagnosis and treatment for nonunion of osteoporotic vertebral fractures ( version 2025), based on existing literature and clinical experience and adhering to principles of scientific rigor and practicality. The guideline provided 13 evidence-based recommendations encompassing diagnosis and treatment of OVF nonunion, aiming to standardize its clinical management.