BACKGROUND:The preparation of curved root canals is a difficult point in root canal treatment,and the main way used in clinical preparation for curved root canals is to gradually deepen the technique,but this technique is prone to lateral penetration when preparing curved root canals,resulting in treatment failure.In view of this situation,some scholars have proposed the use of touch activation technology to prepare,but there are few studies on the influence of this technology combined with different mechanical nickel-titanium instruments on the forming effect of curved root canals at home and abroad.OBJECTIVE:To observe the shaping effect of WaveOneGold,Trunatomy and M3-Pro mechanized nitinol device preparation root canal by using resin simulated root canal step-down technology and tactile controlled activation.METHODS:60 single-bending resin simulated root canals were divided into 6 groups(r=10)according to the random number table method according to the nitinol instrument used.The A1 group was prepared with step-down+WaveOneGold;the A2 group was prepared with step-down+Trunatomy,and the A3 group was prepared with step-down+M3-Pro.Tactile controlled activation+WaveOneGold was used for preparation in group B1;tactile controlled activation+Trunatomy was used for group B2,and tactile controlled activation+M3-Pro was used for preparation in group B3.After the preparation was completed,the pre-preparation and posterior root canal images are obtained using a dental surgical microscope.The root canal offset was analyzed before and after preparation.RESULTS AND CONCLUSION:(1)When WaveOneGold was used,the root canal deviation at 1,4,and 7 mm from the apex was smaller with the tactile controlled activation technique than with the step-down technique(P＜0.05);when Trunatomy was used,the root canal deviation at 6,8,and 10 mm from the apex was smaller with the tactile controlled activation technique than with the step-down technique(P＜0.05);when M3-Pro was used,the root canal deviation at 1,2,and 3 mm from the apex was smaller with the tactile controlled activation technique than with the step-down technique(P＜0.05).(2)When the step-down technique was used,the root canal deviation at 1,4,5,and 7 mm from the apex was smaller with the Trunatomy than with the other two files(P＜0.05),and the root canal deviation at 1,2,3,and 6 mm from the apex was larger with the M3-Pro machine-made nickel-titanium instrument than with the other two files(P＜0.05);when the tactile controlled activation technique was used,the root canal deviation at 2,5,6,8,and 9 mm from the apex after preparation with the Trunatomy file was smaller than that of the other two groups(P＜0.05),and the root canal deviation at 1,4,5,6,and 7 mm from the apex after preparation with the M3-Pro file was larger than that of the other two groups(P＜0.05).(3)The results showed that the three files could cause root canal deviation when preparing root canals.The three files combined with the tactile controlled activation technique could reduce the root canal deviation at some sites of the root canal.The root canal deviation at some sites of the Trunatomy file was less than that of the other two files.

BACKGROUND:The preparation of curved root canals is a difficult point in root canal treatment,and the main way used in clinical preparation for curved root canals is to gradually deepen the technique,but this technique is prone to lateral penetration when preparing curved root canals,resulting in treatment failure.In view of this situation,some scholars have proposed the use of touch activation technology to prepare,but there are few studies on the influence of this technology combined with different mechanical nickel-titanium instruments on the forming effect of curved root canals at home and abroad.OBJECTIVE:To observe the shaping effect of WaveOneGold,Trunatomy and M3-Pro mechanized nitinol device preparation root canal by using resin simulated root canal step-down technology and tactile controlled activation.METHODS:60 single-bending resin simulated root canals were divided into 6 groups(r=10)according to the random number table method according to the nitinol instrument used.The A1 group was prepared with step-down+WaveOneGold;the A2 group was prepared with step-down+Trunatomy,and the A3 group was prepared with step-down+M3-Pro.Tactile controlled activation+WaveOneGold was used for preparation in group B1;tactile controlled activation+Trunatomy was used for group B2,and tactile controlled activation+M3-Pro was used for preparation in group B3.After the preparation was completed,the pre-preparation and posterior root canal images are obtained using a dental surgical microscope.The root canal offset was analyzed before and after preparation.RESULTS AND CONCLUSION:(1)When WaveOneGold was used,the root canal deviation at 1,4,and 7 mm from the apex was smaller with the tactile controlled activation technique than with the step-down technique(P＜0.05);when Trunatomy was used,the root canal deviation at 6,8,and 10 mm from the apex was smaller with the tactile controlled activation technique than with the step-down technique(P＜0.05);when M3-Pro was used,the root canal deviation at 1,2,and 3 mm from the apex was smaller with the tactile controlled activation technique than with the step-down technique(P＜0.05).(2)When the step-down technique was used,the root canal deviation at 1,4,5,and 7 mm from the apex was smaller with the Trunatomy than with the other two files(P＜0.05),and the root canal deviation at 1,2,3,and 6 mm from the apex was larger with the M3-Pro machine-made nickel-titanium instrument than with the other two files(P＜0.05);when the tactile controlled activation technique was used,the root canal deviation at 2,5,6,8,and 9 mm from the apex after preparation with the Trunatomy file was smaller than that of the other two groups(P＜0.05),and the root canal deviation at 1,4,5,6,and 7 mm from the apex after preparation with the M3-Pro file was larger than that of the other two groups(P＜0.05).(3)The results showed that the three files could cause root canal deviation when preparing root canals.The three files combined with the tactile controlled activation technique could reduce the root canal deviation at some sites of the root canal.The root canal deviation at some sites of the Trunatomy file was less than that of the other two files.

Objective To investigate the short- and long-term prognoses and the risk factors affecting “textbook outcome” (TO) after laparoscopic pancreaticoduodenectomy (LPD) for pancreatic ductal adenocarcinoma (PDAC). Methods The clinical and follow-up data of patients diagnosed with PDAC and treated with LPD from January 2019 to December 2022 were retrospectively analyzed. The prognosis was compared between TO and non-TO groups, and univariate and multivariate logistic regression analyses were used to identify independent prognostic factors for TO. Results A total of 284 patients were enrolled in this study, including 185 cases in the TO group and 99 cases in the non-TO group. The 1-, 3- and 5-year overall survival (OS) rates of the TO and non-TO groups with PDAC were 87.3% vs. 85.9%, 52.5% vs. 38.4%, and 18.0% vs. 4.5%, respectively (P=0.020); the recurrence-free survival (RFS) rates were 74.1% vs. 65.7%, 27.1% vs. 21.0%, and 10.0% vs. 0%, respectively (P=0.042). Multivariate logistic regression analysis showed that operation time >360 min (OR=0.561, 95%CI: 0.321-0.979, P=0.042), intraoperative blood loss >400 ml (OR=0.392, 95%CI: 0.175-0.879, P=0.023), hard or tough texture of pancreas (OR=2.240, 95%CI: 1.247-4.022, P=0.007), and main pancreatic duct diameter >3 mm (OR=1.931, 95%CI: 1.126-3.312, P=0.017) were independent prognostic factors for TO. Conclusion After the learning curve, more than 60% of patients with PDAC can achieve TO after LPD. The chances of achieving TO are significantly reduced when the operation time >360 min, the intraoperative blood loss >400 ml, the texture of pancreas was soft, and the diameter of the main pancreatic duct >3 mm.

Objective To explore the feasibility of phase-contrast CT for three-dimensional visualization of in vitro intrahepatic vessels and necrotic foci in mouse model of acute liver injury(ALI).Methods Six clean grade male wild-type C57BL/6 mice were randomly divided into model group and control group(each n=3).The mice in model group were fed with overdose of acetaminophen to induce ALI,while those in control group were fed with the same amount of distilled water.After 24 h,the mice were all sacrificed,the livers were harvested and then fixed and dehydrated.Phase-contrast CT images of in vitro liver were acquired,sectional and three-dimensional images were reconstructed.The effect of phase-contrast CT for displaying the outline of liver and internal vessels and necrotic foci were observed,the maximum diameter and volume of necrotic foci were quantitatively analyzed,and the results of phase-contrast CT were compared with pathological findings.Results The original projection and sectional images of phase-contrast CT clearly showed the outline of in vitro liver and internal vasculatures.Necrotic foci within the liver were found in model group,but not in control group.The findings of phase-contrast CT corresponded accurately to those of pathology.Three-dimensional reconstruction images of phase-contrast CT clearly displayed intrahepatic portal vein system and hepatic vein system in both groups,and discontinuous punctate necrotic foci within the liver were found in model group,mainly distributed around hepatic vein,with a median maximum diameter of 18.50 μm and a median volume of 5 870.11 μm3,but was not observed in control group.Conclusion Phase-contrast CT could be used in three-dimensional visualization of intrahepatic vessels and necrotic foci of in vitro liver in mouse model of ALI.

Objective To investigate the brain voxel-mirrored homotopic connectivity(VMHC)alterations in patients with ves-tibular migraine(VM)by using resting-state functional magnetic resonance imaging(rs-fMRI).Methods The rs-fMRI data of 30 VM patients(VM group)and 30 healthy volunteers(control group)were prospectively collected.The brain VMHC values in all subjects were calculated and the differences between the two groups were compared.The correlations between VMHC values of significant brain regions and clinical scale scores were analyzed in the VM group.Results Compared with the control group,the VMHC values of the cerebellum region 6,orbital inferior frontal gyrus,insula,superior temporal gyrus and postcentral gyrus in the VM group were all decreased[cluster-level family wise error(FWE)corrected,Pvoxel-level<0.001,Pcluster-level<0.05].In the VM group,the VMHC values of the postcentral gyrus were negatively correlated with dizziness handicap inventory(DHI)score(r=-0.383,P=0.037).Additionally,the VMHC values of the insula were negatively correlated with headache impact test-6(HIT-6)score(r=-0.430,P=0.018).Conclusion VM patients have altered VMHC in certain brain regions,indicating related dysfunctions in vestibule,pain,hearing and emotion.

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 investigate the epidemiological characteristics and risk factors of hyperhomocysteinemia(HHcy)in military aircrew.Methods A retrospective study was conducted on 506 aircrew convalescents undergoing health examination from September 2023 to April 2024.Demographic,lifestyle,and biochemical data were analyzed.The risk factors of HHcy were identified by x2 test and multivariate Logistic regression.Results The HHcy detection rate was 21.94%(111/506),with a median homocysteine(Hcy)level of 11.75(9.70-14.30)μmol/L.Multivariate analysis revealed that smoking(OR=2.093,95%CI:1.313-3.336),service in conventional fighter aircraft(OR=1.716,95%CI:1.063-2.770),elevated low-density lipoprotein cholesterol(LDL-C)(OR=2.510,95%CI:1.413-4.458),and elevated bilirubin(OR=2.360,95%CI:1.509-3.691)were independent risk factors for HHcy(all P<0.05).Conclusion There is a high prevalence of HHcy in military pilots.It is strongly associated with smoking,aircraft type,and metabolic abnormalities.It is recommended to incorporate Hcy testing into routine physical examination,implement risk factor-based stratified interventions,and establish an atherosclerotic cardiovascular diseases early warning system integrating vascular imaging and risk assessment,aiming to reduce cardiovascular risks and safeguard combat effectiveness.