Objective:To determine the epidemic characteristics of polymyxin resistance ( mcr) genes of Enterobacteriales colonized in patients admitted to hospitals in Zhejiang, Henan, Gansu and Shandong provinces in China in 2023. Methods:A comprehensive collection of 667 fecal specimens from patients admitted to five medical facilities across the provinces of Zhejiang, Henan, Gansu, and Shandong in 2023 was collected. Epidemiological characteristics of Enterobacteriales bacteria positive for the mcr gene were examined, employing techniques such as microbial culturing, using agarose gel electrophoresis, PCR, whole-genome sequencing, bioinformatics analysis, and the induction of antimicrobial resistance. Statistical analysis was subsequently applied to the gathered data. Results:Among 667 fecal samples from admitted patients, five samples were positive for mcr gene, with a carrier rate of 0.75%(5/667), and from two of the samples, two different strains carrying the mcr gene were isolated, respectively. A total of seven strains of Enterobacteriales carrying the mcr gene were detected, of which four strains carried mcr-1 gene and three strains carried mcr-9 gene. The positive isolates included three strains of Escherichia coli, one strain of Citrobacter braakii, Citrobacter freundii, one strain of Klebsiella pneumoniae, and one strain of Enterobacter hormaechei. The seven mcr positive strains were isolated from two distinct geographical locations within China, with four from Zhejiang Province and three from Henan Province. After whole-genome sequencing, it was found that the 16S rRNA sequences of the three strains of mcr-1 positive Escherichia coli had high homology. The three isolates of mcr-9 positive strains preserved a significant degree of homology within the mcr-9 and wbuC regions. Following polymyxin exposure, there was a marked difference in the growth kinetics of the ZJ-307, HN-11-1, and HN-135 strains post-induction compared to their pre-induction growth rates, and their motility capacity was reduced. Conclusions:The prevalence of Enterobacteriales harboring the mcr gene is minimal among hospitalized patients. However, it is noteworthy that these genes are prone to horizontal transfer. They can move into drug-resistant strains, which may have elevate minimum inhibitory concentration(MIC). Resistance to polymyxin can alter the bacterial growth rate and motility, potentially impacting the MIC of other antibiotics, thereby complicating clinical management. Consequently, it is imperative to focus on the proactive screening of susceptible populations to prevent the further dissemination of plasmid-mediated polymyxin resistance among clinically significant gram-negative bacterial pathogens.

Aging is characterized by a gradual deterioration of the physiological integrity of cells,tissues,and or-gans,resulting in a decrease in the body's physiological functions and an acceleration of the onset of age-related diseases,ultimately leading to death.The aging of the liver,which is a critical metabolic organ,is closely linked to various chronic liver diseases,such as hepatitis,liver fibrosis,and cirrhosis,and it ex-acerbates their prognosis and is a primary risk factor for their development at all stages.Therefore,a comprehensive understanding of the causes,mechanisms,and potential therapeutic targets associated with liver aging holds significant clinical importance for delaying or potentially reversing liver aging and for treating chronic liver diseases.Stem cells,which are potential anti-aging agents,present a promising and effective alternative for managing liver aging.In this review,we systematically assess the driving factors,characteristics,and underlying mechanisms of liver aging.We then discuss the current status of the use of stem cells to mitigate liver senescence and address related liver diseases.The review reveals that a stem cell-based approach represents a promising therapeutic strategy for combating liver aging and associated diseases.

Medical therapy and surgical intervention are the two primary approaches for treating myocardial bridge.However,there remains controversy regarding the use of coronary artery bypass grafting(CABG)and myocardial bridge unroofing.Here,we report a case of myocardial infarction following CABG in a patient with a myocardial bridge.The patient was admitted to Lanzhou First Peopie's Hospital with persistent chest pain,chest tightness,and shortness of breath lasting 2 hours.Physical examination revealed no significant abnormalities.Electrocardiography(ECG)indicated extensive anterior wall myocardial infarction.Laboratory findings showed myoglobin levels of 140.1 ng/ml and troponin Ⅰ levels of 2.59 ng/ml,with no other significant abnormalities.The initial diagnosis was acute extensive anterior wall myocardial infarction.Emergency coronary angiography revealed a myocardial bridge in the mid-segment of the left anterior descending artery(LAD).Emergency CABG using the left internal mammary artery to the LAD was performed,leading to symptomatic improvement,and the patient was discharged in stable condition.However,the patient experienced a recurrent myocardial infarction seven years post-surgery and received secondary preventive medical therapy.The patient is currently under ongoing follow-up care.CABG is an effective treatment for myocardial bridge.However,based on the case reported in this study,we recommend careful evaluation of whether a patient may benefit from CABG.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Objective To investigate the correlation between serum uric acid(SUA)levels and incident chronic kidney disease(CKD)in middle-aged and elderly Chinese population and gender differences.Methods Based on the longitudinal survey data of China Health and Retirement Longitudinal Study from 2011 to 2015,the CKD-Epidemiology Collaboration cystatin C formula was used to estimate the glomerular filtration rate(eGFR),and 4 119 participants with normal renal function(eGFR≥60 mL·min-1·1.72 m-2)at baseline were included.Incident CKD was defined as eGFR<60 mL·min-1·1.72 m-2 at the follow-up in 2015.Logistic regression analysis was used to analysis the association of SUA levels at baseline and incident CKD among different genders.Restricted cubic spline analysis was used to analyze the dose-response relationship.Results After 4-year follow-up,127 participants developed incident CKD,including 57 males and 70 females.Multivariate Logistic regression analysis showed that elevated SUA levels were independently associated with the risk of incident CKD(OR=1.532,P<0.001).For each 1 mg/dL increase in SUA,the risk of incident CKD increased by 33.6%in males(OR=1.336,P=0.012)and 77.5%in females(OR=1.755,P<0.001).Restricted cubic spline analysis showed a linear positive correlation between SUA levels and incident CKD in both males and females.Participants were divided into four groups according to SUA quartiles(Q1-Q4).Multivariate Logistic regression analysis indicated a significant increase in the risk of incident CKD in Q3 group(3.75 mg/dL4.43 mg/dL)compared with Q1 group in females(Q3 group:OR=2.571,P=0.045;Q4 group:OR=3.666,P=0.005).Conclusion SUA is an independent risk factor for incident CKD in the middle-aged and elderly population.In females,serum uric acid levels exceeding 3.75 mg/dL are associated with an increased risk of incident CKD.

With the increasing demand for dynamic,real-time and rapid qualitative analysis of chemical composition in areas such as emergency response and space exploration,chip-scale mass spectrometers have attracted significant attention.These devices are expected to drive the integration of mass spectrometry with micro/nano-fabrication and intelligent sensing technologies,fostering profound innovation and breakthroughs in analytical chemistry.As an excellent mass analyzer,the ion trap exhibits numerous advantages,and its miniaturization creates favorable conditions for the high-density integration of miniature mass spectrometers.However,the reduction in ion storage capacity may compromise its sensitivity and dynamic range,rendering the study of ion unidirectional ejection in highly miniaturized ion traps of significant practical importance.In this work,a research was conducted on achieving efficient ion unidirectional ejection while maintaining high mass resolution in the extremely miniature hyperbolic linear ion trap(M-HLIT)with a field radius of 1 mm,and an electric field compensation method was proposed,which combined asymmetric electrode stretching and unbalanced RF voltage to achieve high-precision optimization of the electric field composition.Simulations showed that in an ideal structure,this method achieved 100％unidirectional ejection efficiency with the mass resolution of 518,significantly outperforming traditional asymmetric structure method(365)and unbalanced voltage method(321).Following the introduction of ion ejection slots,further optimization through bidirectional stretching and electrical parameters improved the resolution to 790 while maintaining a unidirectional ejection efficiency of 93％.This method eliminated the requirement for additional excitation voltage,offering an ideal solution for the miniature mass analyzer with high detection performance of chip-level mass spectrometers.

Lentiviral vectors(LVs)are key gene delivery tools for integrating target genes into the host genome,but they may also pose risks of insertional mutagenesis.The vector copy number(VCN)in cells is critical for determining the safety of gene modification.However,the reliability and accuracy of its quantification process are influenced by multiple factors.Developing cell reference materials with specific vector copy numbers represents a viable approach to enhance the reliability and consistency of measurement results,enabling quality control of the quantification process and traceability of outcomes.However,the preparation of such reference materials faces challenges in cell sample design,preparation protocols,and advanced quantification techniques.In this study,T lymphocyte cell line Jurkat-based reference materials with LV gene copy numbers of 1 and 2 copy/cell were developed.A high-precision duplex digital polymerase chain reaction(dPCR)method was established to quantify the LV gene and endogenous genes simultaneously.Additionally,the results of dPCR were cross-validated through next-generation sequencing and flow cytometric analysis.Ultimately,confocal microscopy characterization results showed that the developed cell reference materials had intact morphology.The quantification result of VCN-1 was(1.07±0.11)copy/cell,and that of VCN-2 was(2.09±0.21)copy/cell.These cell reference materials demonstrated compliance with stability and homogeneity requirements,and could be applied for quality control throughout the VCN measurement workflow and metrological traceability,improving the accuracy,comparability,and validity of copy number measurements.

Anterior cruciate ligament (ACL) reconstruction yields favorable outcomes for restoring anteroposterior stability of the knee joint in patients with ACL tears. However, some patients still exhibit positive knee pivot shift after ACL reconstruction. Currently, combined ACL and anterolateral ligament(ALL) reconstruction has been accepted by most scholars. This surgical technique can restore the rotational stability of the knee joint in patients postoperatively and facilitate the early besumption of sports training after surgery. This article reviews the anatomical research, isometry-like point research, and reconstruction indications of the anterolateral ligament, as well as the surgical approaches, graft tunnel convergence, and reconstruction outcomes of combined anterior cruciate ligament and anterolateral ligament reconstruction.

With the rapid development of generative artificial intelligence(GAI)technologies,their widespread application in academic research and writing is continuously expanding the boundaries of sci-entific inquiry.However,this trend has also raised a series of ethical and regulatory challenges,inclu-ding issues related to authorship,content authenticity,citation accuracy,and accountability.In light of the growing involvement of AI in generating academic content,establishing an open,controllable,and trustworthy ethical governance framework has become a key task for safeguarding research integrity and maintaining trust within the academic community.This expert consensus outlines ethical requirements across key stages of AI-assisted academic writing-including topic selection,data management,citation practices,and authorship attribution.It aims to clarify the boundaries and ethical obligations surrounding AI use in academic writing,ensuring that technological tools enhance efficiency without compromising in-tegrity.The goal is to provide guidance and institutional support for building a responsible and sustainable research ecosystem.