OBJECTIVE: To investigate the biomechanical characteristics of retrograde tibial nailing (RTN) and distal tibial L-shaped plating in the internal fixation of distal tibial fractures. METHODS: Fourteen fresh adult tibia specimens were selected, comprising 7 males and 7 females aged from 34 to 55 years old. The specimens were randomly divided into experimental group and control group by numerical table method with 7 specimens in each group. RTN was used for internal fixation of distal tibial fractures in the experimental group, and L-shaped plate was used for internal fixation of distal tibial fractures in the control group. The axial compression properties of the two groups of specimens were tested under the pressure of 100, 200, 300, 400, and 500 N after operation, and torsional resistance at torque levels of 1.0, 2.0, 3.0, 4.0, 5.0 N·m. The anti-fatigue performance of the specimens was tested at 500 N pressure for 3 000 and 10 000 cycles. X-ray fluoroscopy was performed to observe whether the the internal fixator was deformed and whether the screw was loosened or broken. RESULTS: When the pressure was 400 N and 500 N, the axial compression displacement of the experimental group was (1.11±0.06) mm and (1.24±0.05) mm, which were smaller than those of the control group (1.21±0.08) mm and (1.37±0.11) mm, and the differences were statistically signific (P<0.05). Under the pressure of 500 N, the axial compression stiffness of the experimental group was (389.24±17.79) N·mm^-1, which was significantly higher than that of the control group (362.37±14.44) N·mm^-1(P<0.05). When the torque was 4 and 5 N·m, the torsion angles of the experimental group were (2.97±0.23) ° and (3.41±0.17) °, which were smaller than those of the control group (3.31±0.28) ° and (3.76±0.20) °, and the differences were statistically significant (P<0.05). When the torque was 5 N·m, the torsional stiffness of the experimental group was (1.48±0.07) N·m per degree, which was higher than that of the control group (1.36±0.06) N·m per degree, and the difference was statistically significant (P<0.05). For the intragroup comparison of fatigue resistance, the differences in axial compression displacement between the two groups were not statistically significant at 3 000 and 10 000 cycles (all P>0.05). When 3 000 times and 10 000 times of compression, the axial compression displacement of the experimental group was (1.38±0.08), (1.43±0.07) mm, which was smaller than that of the control group (1.51±0.10), (1.54±0.08) mm, the differences were statistically significant (P<0.05). In the experimental group, no screw loosening, fracture or internal fixation deformation was found, while in the control group, locking screw loosening occurred in 2 models after 10 000 pressures. CONCLUSION The biomechanical performance of RTN is obviously better than that of the distal tibial L-shaped plate, which provides biomechanical data support for the clinical application of RTN.
Humans ; Female ; Male ; Adult ; Tibial Fractures/physiopathology* ; Middle Aged ; Biomechanical Phenomena ; Bone Plates ; Fracture Fixation, Internal/instrumentation* ; Bone Nails ; Tibia/surgery*

BACKGROUND: Based on the China-VHD database, this study sought to develop and validate a Valvular Heart Disease- specific Age-adjusted Comorbidity Index (VHD-ACI) for predicting mortality risk in patients with VHD. METHODS & RESULTS: The China-VHD study was a nationwide, multi-centre multi-centre cohort study enrolling 13,917 patients with moderate or severe VHD across 46 medical centres in China between April-June 2018. After excluding cases with missing key variables, 11,459 patients were retained for final analysis. The primary endpoint was 2-year all-cause mortality, with 941 deaths (10.0%) observed during follow-up. The VHD-ACI was derived after identifying 13 independent mortality predictors: cardiomyopathy, myocardial infarction, chronic obstructive pulmonary disease, pulmonary artery hypertension, low body weight, anaemia, hypoalbuminaemia, renal insufficiency, moderate/severe hepatic dysfunction, heart failure, cancer, NYHA functional class and age. The index exhibited good discrimination (AUC, 0.79) and calibration (Brier score, 0.062) in the total cohort, outperforming both EuroSCORE II and ACCI (P < 0.001 for comparison). Internal validation through 100 bootstrap iterations yielded a C statistic of 0.694 (95% CI: 0.665-0.723) for 2-year mortality prediction. VHD-ACI scores, as a continuous variable (VHD-ACI score: adjusted HR (95% CI): 1.263 (1.245-1.282), P < 0.001) or categorized using thresholds determined by the Yoden index (VHD-ACI ≥ 9 vs. < 9, adjusted HR (95% CI): 6.216 (5.378-7.184), P < 0.001), were independently associated with mortality. The prognostic performance remained consistent across all VHD subtypes (aortic stenosis, aortic regurgitation, mitral stenosis, mitral regurgitation, tricuspid valve disease, mixed aortic/mitral valve disease and multiple VHD), and clinical subgroups stratified by therapeutic strategy, LVEF status (preserved vs. reduced), disease severity and etiology. CONCLUSION The VHD-ACI is a simple 13-comorbidity algorithm for the prediction of mortality in VHD patients and providing a simple and rapid tool for risk stratification.

Osteoarthritis (OA), the most prevalent joint disease of late life, is closely linked to cellular senescence. Previously, we found that the senescence of fibroblast-like synoviocytes (FLS) played an essential role in the degradation of cartilage. In this work, single-cell sequencing data further demonstrated that cartilage acidic protein 1 (CRTAC1) is a critical secreted factor of senescent FLS, which suppresses mitophagy and induces mitochondrial dysfunction by regulating SIRT3 expression. In vivo, deletion of SIRT3 in chondrocytes accelerated cartilage degradation and aggravated the progression of OA. Oppositely, intra-articular injection of adeno-associated virus expressing SIRT3 effectively alleviated OA progression in mice. Mechanistically, we demonstrated that elevated CRTAC1 could bind with NRF2 in chondrocytes, which subsequently suppresses the transcription of SIRT3 in vitro. In addition, SIRT3 reduction could promote the acetylation of FOXO3a and result in mitochondrial dysfunction, which finally contributes to the degradation of chondrocytes. To conclude, this work revealed the critical role and underlying mechanism of senescent FLSs-derived CRTAC1 in OA progression, which provided a potential strategy for the OA therapy.

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.

Aim To detect the non-coding RNA(ncRNA)expression profile of neuroglioma cells via whole transcriptome sequencing,establish the ceRNA network and reveal the molecular mechanism of ncRNA participating in the inhibition of neuroglioma cell prolif-eration by melatonin.Methods Neuroglioma cells were intervened with by 0,2,4,6 and 8 mmol·L-1 melatonin for 24,48 and 72 h,and the inhibitory effect of melatonin on cell proliferation was detected via CCK-8;after the intervention of 0 and 4 mmol·L-1 melatonin to U251 cells for 24 h,differentially ex-pressed miRNA(DEmiRNA),lncRNA(DElncRNA)and mRNA(DEmRNA)were detected through whole transcriptome sequencing,along with GO and KEGG enrichment analysis of DEmRNA;the ceRNA network was constructed,and the key gene expression of ceR-NA was verified through qRT-PCR.Results Melato-nin exerts a time-dose-dependent inhibitory effect on the proliferation of neuroglioma cells;a total of 5049 DEmRNA,635 DElncRNA and 146 DEmiRNA in 0 and 4 mmol·L-1 melatonin groups were screened out via whole transcriptome sequencing;DEmRNAs were mainly enriched in cancer-related signaling pathways,such as ferroptosis,mTOR signaling pathway,FoxO signaling pathway and cell cycle;the ceRNA network included 4 lncRNAs,3 miRNAs and 48 mRNAs.As verified through real-time PCR,the expressions of hsa-miR-129-5p,hsa-miR-362-5p,LINC00707 and SLC16A1-AS1 of U251 cells were consistent with the sequencing results,and the gene expression of U87 cells was basically consistent with the sequencing re-sults.Conclusions Melatonin affects cancer-related signaling pathways through the differential expression of ncRNA so as to inhibit the proliferation of U251 cells;the ceRNA network composed of LINC00707,SLC16A1-AS1,hsa-miR-129-5p and hsa-miR-362-5p may take a part in the molecular mechanism of melato-nin in inhibiting neuroglioma cell proliferation.

Objective To explore the impact of admission modes on the reperfusion time and short-term prognosis of patients with acute ST-segment elevation myocardial infarction(STEMI).Methods 497 patients who visited the Chest Pain Center of Xiamen Cardiovascular Hospital of Xiamen University from January 2023 to November 2024 and were diagnosed with STEMI were included.All patients received direct percutaneous coronary intervention.According to admission modes,the patients were divided into the self-referral group(122 cases),emergency medical service group(EMS)(51 cases)and transfer PCI group(324 cases).The basic characteristics,reperfusion time,complications between group were compared.Results The age of the patients in this study was(58.64±13.62)years old,and there were 423 male cases(85.11%).Compared with the self-referral group and the EMS group,the time of door-wire in transfer PCI group was shorter[35(29,45)min vs.43(35,53)min vs.43(33,48)min,P＜0.001],but the time of first medical contact-wire was longer[123(80,192)min vs.43(35,52)min vs.57(51,76)min,P＜0.001].Compared with the self-referral group and the transfer PCI group,the time of symptom-to-first medical contact and the time of symptom-to-wire in EMS group were both shorter,which were[55(32,136)min vs.185(116,360)min vs.120(60,236)min,P＜0.001]and[136(101,188)min vs.228(169,413)min vs.282(190,400)min,P＜0.001].The incidence of infections in the transfer PCI group was lower than that in the self-referral group(12.65%vs.22.95%,P＜0.05).Conclusions To comprehensively enhance the treatment effect,it is necessary to prioritize the promotion and continuous optimization of the response process of EMS,simultaneously strengthen the standardized collaboration of referral,and enhance the identification ability of STEMI through public education to reduce the delay of self-referral patients..

Objective To summarize the clinical features,treatment and prognosis of patients with primary central nervous system lymphoma(PCNSL)with clonal bone marrow B cells,and to explore the influence on clinical diagnosis and treatment.Methods PCNSL patients with clonal bone marrow B cells diagnosed by flow cytometry between Jan 2020 and Jul 2023 at Huashan Hospital of Fudan University were enrolled.The auxiliary examination data of these patients were collected,including complete blood count,routine biochemistry,bone marrow aspiration and biopsy,contrast-enhanced brain MRI,and whole-body PET-CT.Kaplan-Meier was used to draw the survival curve,and relevant literature was reviewed.Results A total of 223 newly diagnosed PCNSL patients were included,187 of whom completed bone marrow puncture and biopsy evaluation.We found clonal bone marrow B cells in 16 of 187 cases(8.56%)by flow cytometry.2 patients showed B lymphoma involving the bone marrow.All patients received a high-dose methotrexate based chemotherapy.The median progression free survival(PFS)of 16 patients with clonal bone marrow B cells was 11.1 months,and the median PFS of 171 patients with normal bone marrow was 12.6 months.There was no significant difference in the PFS between the two groups.Conclusion PCNSL with clonal bone marrow B cells had no specific clinical features,but bone marrow flow cytometry showed clonal B cells.High-dose methotrexate treatment regimen is effective.There was no significant difference in PFS for PCNSL patients with clonal B cells and normal findings in bone marrow.Clonal B cells in bone marrow may be caused by monoclonal B-cell lymphocytosis(MBL),lymphoma involves the bone marrow and the presence of common precursor cells.Bone marrow examination should be performed in the initial evaluation of suspected PCNSL.

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.