Instrument separation is a critical complication during root canal therapy, impacting treatment success and long-term tooth preservation. The etiology of instrument separation is multifactorial, involving the intricate anatomy of the root canal system, instrument-related factors, and instrumentation techniques. Instrument separation can hinder thorough cleaning, shaping, and obturation of the root canal, posing challenges to successful treatment outcomes. Although retrieval of separated instrument is often feasible, it carries risks including perforation, excessive removal of tooth structure and root fractures. Effective management of separated instruments requires a comprehensive understanding of the contributing factors, meticulous preoperative assessment, and precise evaluation of the retrieval difficulty. The application of appropriate retrieval techniques is essential to minimize complications and optimize clinical outcomes. The current manuscript provides a framework for understanding the causes, risk factors, and clinical management principles of instrument separation. By integrating effective strategies, endodontists can enhance decision-making, improve endodontic treatment success and ensure the preservation of natural dentition.
Humans ; Root Canal Therapy/adverse effects* ; Consensus ; Root Canal Preparation/adverse effects*

Objective:To investigate the value of nomogram model based on CT features in differentiating ectopic pancreas (EP) from gastrointestinal stromal tumors (GIST) with a long diameter less than 3 cm.Methods:This study was a case-control study. The clinical and imaging data of 43 patients with EP and 90 patients with GIST confirmed by pathology in the Affiliated Hospital of Guizhou Medical University from August 2013 to March 2024 were retrospectively analyzed. Preoperative CT images were analyzed to obtain qualitative features (number of lesions, location, morphology, growth pattern, borders, cystic degeneration, calcification, ulceration, catheter sign, central umbilication) and quantitative features (lesion long diameter, short diameter, long/short diameter, lesion and normal pancreas arterial-phase and venous-phase CT values, and enhancement ratio). Statistical analyses, including independent sample t-tests, Mann-Whitney U tests, χ2 tests, and Fisher exact tests, were performed to compare CT characteristics between the two groups. Binary logistic regression analysis was used to obtain independent predictors to identify the two groups, to establish a joint model, and to draw a nomogram. The discriminative performance of the independent predictors and the combined model was assessed using receiver operating characteristic (ROC) curves, while calibration curves were used to evaluate model fit. Results:The differences in age, location, morphology, border, catheter sign, central umbilication, short diameter, long/short diameter, arteriovenous phase enhancement CT value and arteriovenous phase enhancement ratio were statistically significant between the EP group and the GIST group (all P<0.05). The logistic analysis showed that the differences in age ( OR=0.920, 95% CI 0.885-0.956, P<0.001), border ( OR=5.994, 95% CI 2.111-17.022, P=0.001), long/short diameter ( OR=7.820, 95% CI 1.841-33.224, P=0.005), and venous phase enhancement ratio ( OR=8.847, 95% CI 1.103-70.972, P=0.040) were the independent predictors for distinguishing EP from GIST, and the area under the ROC curve (AUC) were 0.782 (95% CI 0.698-0.866), 0.684 (95% CI 0.600-0.767), 0.705 (95% CI 0.607-0.803), and 0.693 (95% CI 0.605-0.781), respectively. Combined age, border, long diameter/short diameter and venous phase enhancement ratio were plotted in a nomogram with an AUC of 0.881 (95% CI 0.817-0.945), sensitivity and specificity of 74.4% and 93.3%, respectively. The calibration curve demonstrated a strong agreement between predicted and actual probabilities (Hosmer-Lemeschow test, P=0.267). Conclusions:CT imaging reveals significant differences between EP and small GISTs (<3 cm). EP is more likely when patients are younger and lesions exhibit indistinct borders, a higher long-to-short diameter ratio, and greater venous-phase enhancement. The nomogram derived from CT features provides a valuable tool for differentiating EP from GIST.

Integrated metabolomic and lipidomic profiling,utilizing liquid chromatography coupled with high-resolution mass spectrometry(LC-HRMS),has emerged as a pivotal strategy for biomarker discovery.However,the inherent polarity disparity between metabolites and lipids complicates simultaneous analysis.To address this,a dual-stationary phase polarity-extended liquid chromatography(PELC)system was developed,which surpassed conventional one-dimensional LC(1D-LC)by enabling comprehensive coverage of both polar and non-polar compounds within a single injection.This system enhanced chromatographic resolution,peak capacity,and throughput while minimizing analytical variability.Extracellular vesicles(EVs),lipid bilayer-enclosed nanoparticles ubiquitously present in biofluids,had gained prominence as reservoirs of cancer biomarkers due to their cargo stability and pathophysiological relevance.Herein,the application of PELC-HRMS for concurrent metabolome-lipidome profiling in EVs was pioneered.A total of 193 metabolites were identified using this technique coupled with MS-DIAL software and Human Metabolome Database.Subsequently,this technique was employed to explore potential biomarkers for prostate cancer(PCa).Multivariate analysis identified 17 differentially abundant metabolites in PCa,implicating dysregulated pathways including purine metabolism,starch and sucrose metabolism,galactose metabolism,cysteine and methionine metabolism,and biosynthesis of unsaturated fatty acids.Notably,creatine(AUC=0.92)and DG 42:5(AUC=0.80)demonstrated robust diagnostic efficacy,attributable to their broad polarity ranges and EV-specific enrichment.This study established PELC as a high-fidelity platform for multi-omics integration in complex biospecimens,advancing mechanistic insights into metabolic rewiring and disease pathophysiology.

Objective To establish a rapid screening and analysis method for etomidate and its ana-logues using a portable mass spectrometer equipped with a thermal desorption-atmospheric pressure chemical ionization source-linear ion trap.Methods A 10 μL aliquot of a standard solution at a con-centration of 1 μg/mL was taken,and after the solvent evaporated,the sample was inserted into the in-let of the portable mass spectrometer for detection.By adjusting the collision-induced dissociation pa-rameters,the molecular ion peak and fragment ion peak information of the standard were obtained and used to establish a reference database.In addition,the method was applied to 29 seized liquid and plant samples.Results A screening system for etomidate and its analogues was established based on the portable mass spectrometer and the corresponding mass spectrometry library.The system enables qualitative screening analysis by identifying primary protonated molecular ions and secondary product ions of etomidate and its analogues.The limits of detection for etomidate and its 12 analogues ranged from 0.1 to 10 μg/mL.Etomidate and its analogues were detected in all 29 liquid and plant samples.However,this method could not distinguish between isomeric imidazole esters,such as isopropoxate and propoxate.Additionally,when testing 2-SH-etomidate,there was a false positive for the detection of etomidate.Conclusion This study established a rapid screening method for etomidate and its ana-logues using a portable mass spectrometer.The method combines the high sensitivity of mass spectrome-try with the on-site applicability of portable devices,significantly improving detection efficiency and meeting the on-site detection needs of etomidate and its analogues.

Objective:To investigate whether continued low-dose aspirin (LDA) intervention affects the incidence of pre-eclampsia (PE) and adverse pregnancy outcomes in pregnant women with high-risk PE screening in the first trimester and reassessed as low risk at 28 weeks of gestation.Methods:This study was a prospective observational cohort study. From April 2022 to April 2024, a total of 106 pregnant women who underwent prenatal examination in the Affiliated Jiangyin Hospital of Nantong University were enrolled. They were assessed as high risk of PE by multiple indicators combined screening at 11-13 +6 weeks of gestation, received LDA intervention, and were reassessed as low risk of PE at 28 weeks of gestation. The patients were divided into withdrawal group (49 cases) and continuation group (57 cases). The incidence of PE and adverse pregnancy outcomes were compared between the two groups. Results:(1) There were no statistically significant differences in general conditions and the incidence of pregnancy complications between the two groups (all P>0.05). During the PE risk screening at 11-13 +6 weeks of gestation, there were no statistically significant differences in mean arterial pressure (MAP) and ultrasound uterine artery pulsation index (UtPI) between the two groups (all P>0.05), but the placental growth factor (PlGF) level in the withdrawal group was significantly lower than that in the continuation group ( P=0.023). There was no significant difference in the proportion of pregnant women with high risk of PE before 32 weeks and 34 weeks of pregnancy between the two groups (all P>0.05). (2) There were 7 cases (14%, 7/49) of PE in the withdrawal group, including 1 case (2%, 1/49) of early-onset PE and 3 cases (6%, 3/49) of PE before 37 weeks of pregnancy. There were 11 cases (19%, 11/57) of PE in the continuation group, including 2 cases (4%, 2/57) of early-onset PE and 4 cases (7%, 4/57) of PE before 37 weeks of pregnancy. There were no significant differences in the incidence of PE (including early-onset PE and PE before 37 weeks of pregnancy), gestational hypertension, severe PE, chronic hypertension complicated with PE and chronic hypertension complicated with pregnancy between the two groups (all P>0.05). (3) There were no significant differences in cesarean section rate, preterm birth rate, placental abruption, postpartum hemorrhage, fetal growth restriction, fetal distress rate, neonatal birth weight, neonatal asphyxia, and 1-minute and 5-minute Apgar scores between the two groups (all P>0.05). No stillbirth occurred in the two groups. Conclusion:For pregnant women with high risk of PE screening in the first trimester and taking LDA intervention, there is no difference in the incidence of PE and adverse pregnancy outcomes whether to continue LDA or not after being reassessed as low risk at 28 weeks of gestation.

Objective:To evaluate the lung ultrasound characteristics of mycoplasma pneumoniae pneumonia in children and to investigate the value of lung ultrasound monitoring in clinical diagnosis and treatment.Methods:A retrospective analysis of 62 children with mycoplasma pneumoniae pneumonia admitted to Xi'an Chest Hospital from 7 November to 30 November 2023 was performed，and the characteristic parameters of bedside lung ultrasound and their related clinical data were collected. Pathological lung ultrasound features such as interrupted pleural line，well-spaced B-lines，coalescent B-lines，small subpleural patchy pulmonary consolidation，large pulmonary consolidation and pleural effusion in 12 scan areas of both lungs were observed. The maximum upper and lower diameters，right and left diameters，and anterior and posterior diameters of the large pulmonary consolidations were measured，and the changes in the above signs before and after treatment were measured and compared.Results:In sixty-two children with mycoplasma pneumoniae pneumonia，including 32 males and 30 females，with a mean age of（8.18 ± 2.05）years old and a mean hospital stay of（8.79 ± 2.93）days，lung ultrasound showed interrupted pleural line，well-spaced B-lines，coalescent B-lines，small subpleural patchy pulmonary consolidation，large pulmonary consolidation and pleural effusion，with the incidence of 93.5%（58 /62），33.9%（21/62），32.3%（20/62），59.7%（37/62），66.1%（41/62）and 17.7%（11/62），respectively，in which the large pulmonary consolidations presented rich blood supply were more common in the L6 and L4 areas，while the pleural effusions were more common in the L6 area.The signs of interrupted pleural line，coalescent B-lines，large pulmonary consolidation and pleural effusion were significantly improved after treatment compared with before treatment（all P<0.05）. The upper and lower diameters，left and right diameters，and anterior and posterior diameters of large pulmonary consolidations were significantly reduced after treatment compared with before treatment［（4.19 ± 2.42）cm vs.（2.84 ± 2.31）cm， t=2.613， P=0.011；（2.80 ± 1.82）cm vs.（1.96 ± 1.62）cm， t=2.226， P=0.029；（3.41 ± 2.11）cm vs.（2.12 ± 1.82）cm， t=2.972， P=0.004］.With the process of treatment，the dynamic observation of lung ultrasound showed that the well-spaced B-lines/coalescent B-lines gradually decreased until they completely disappeared or a small number of B-lines remained，and the area of the large pulmonary consolidation showed a dynamic downward trend（all P<0.001），and the area of large pulmonary consolidations gradually decreased until they completely disappeared or only small subpleural patchy pulmonary consolidations and well-spaced/coalescent B-lines remained，and at the same time，the pleural effusion gradually absorbed until it disappeared. Conclusions:Lung ultrasound can detect the distribution area of lung lesions，morphology and blood supply characteristics of children with mycoplasma pneumoniae pneumonia，as well as the dynamic changes after treatment，and lung ultrasound can dynamically monitor and evaluate the progression and regression of the disease in real time，providing a reliable imaging evidence for clinical practice.

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 summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.