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.

Objective:To investigate effects of macrophage polarization on PI3K/Akt/mTOR signaling pathway and inflammatory response of vascular smooth muscle cells.Methods:THP-1 cells were induced to become macrophages by phaboate,then treated with LPS and IFN-γ,IL-4 and IL-13 for 48 h,and cultured with fresh medium without serum for 24 h.Supernatant was used as conditioned medium.Vascular smooth muscle cells were divided into control group,M0 medium group,M1 medium group and M2 medium group.CCK-8 was used to detect cell proliferation,flow cytometry was used to detect cell apoptosis,ELISA was used to detect expressions of inflammatory cytokines IL-1α,IL-6 and TGF-β in supernatant of cells,and mRNA and phosphorylated protein expressions of PI3K,Akt and mTOR in vascular smooth muscle cells were detected by RT-qPCR and Western blot.Results:Compared with control group,cell proliferation ability and TGF-β level in supernatant of M0 medium group were significantly decreased(P<0.01),apoptosis rate,IL-1α and IL-6 levels in cell supernatant,mRNA and protein phosphorylation levels of PI3K,Akt and mTOR in cells were significantly increased(P<0.01).Compared with M0 medium group,cell proliferation ability and TGF-β level in supernatant of M1 medium group were significantly decreased(P<0.05),apoptosis rate,IL-1α and IL-6 levels in cell supernatant,mRNA and protein phosphorylation levels of PI3K,Akt and mTOR in cells were significantly increased(P<0.01),the trend was opposite in M2 medium group(P<0.05).Conclusion:Macrophage polarization can regulate expressions of inflammatory cytokines by regulating PI3K/Akt/mTOR signaling pathway,and participate in inflammatory response in atherosclerosis.

Objective To assess the effectiveness of the Gasdermin D C-terminal fragment(GSDMD-CT)as a novel plasma biomarker for the clinical diagnosis of sepsis.Methods Between July 2021 and November 2024,245 patients from Tangshan Gongren Hospital were enrolled in this study.In accordance with the diagnostic criteria for sepsis and the systemic inflammatory response syndrome(SIRS),patient samples were classified into the sepsis group and the SIRS group.Meanwhile,healthy individuals were selected as the healthy control(HC)group.Sepsis patients were further categorized into the Gram-positive bacterial group,the Gram-negative bacterial group,and the fungal group based on the type of pathogen infection.The levels of GSDMD-CT,C-reactive protein(CRP),and procalcitonin(PCT)were measured in all subjects.Nonparametric tests were employed to compare the differences in various indices among different groups.The diagnostic value of GSDMD-CT in sepsis was evalu-ated by constructing the receiver operating characteristic(ROC)curve.Spearman's correlation analysis was used to examine the relationships among GSDMD-CT,CRP,and PCT.Results The plasma GSDMD-CT levels in the sepsis group 23.02(16.71,33.01)pg/mL and in the SIRS group 16.52(11.26,22.22)pg/mL were significantly higher than those in the healthy control group 7.02(4.42,11.43)pg/mL(U=-10.175,-7.890,P<0.001).Moreover,the plasma GSDMD-CT levels in the sepsis group were significantly higher than those in the SIRS group(U=-2.941,P<0.05).In the Gram-positive bacterial group,the Gram-negative bacterial group,and the fungal group,the GSDMD-CT levels were 23.01(17.16,27.51)pg/mL,23.41(16.78,35.50)pg/mL,and 16.29(14.53,56.27)pg/mL,respectively.When compared with the healthy control group,the GSDMD-CT levels in these three groups were all significantly higher(P<0.05).However,there were no significant differences in GSDMD-CT levels among these three groups(P>0.05).The area under the curve(AUC)of plasma GSDMD-CT for diagnosing sepsis was 0.881(95%confidence interval:0.833～0.929),with a Youden index(YI)of 0.695,a sensitivity of 85.0%,and a specificity of 84.5%.Spearman correlation analysis indicated a weak correlation between GSDMD-CT and C-reactive protein(CRP)(r=0.32,P<0.001)and a positive correlation between GSDMD-CT and procalci-tonin(PCT)(r=0.65,P<0.001).Conclusion GSDMD-CT exhibits significant clinical value in the diagnosis of sepsis and holds great potential as a biomarker in the diagnostic process of sepsis.

OBJECTIVE: EPF3 is a fibrinolysin monomer isolated and purified from Pheretima vulgaris Chen, an earthworm used in traditional Chinese medicine as Dilong for treating blood stasis syndrome. Its composition, anticoagulant and fibrinolytic activities, and relevant mechanisms have been confirmed through in vitro experiments. However, whether it has antithrombotic effects in vivo and can be absorbed by the gastrointestinal tract is unknown. This study evaluates the antithrombotic effect in zebrafish and investigates the gastrointestinal stability and intestinal absorption mechanism of this protein in vitro. METHODS: The antithrombotic effect of EPF3 in vivo was verified using the zebrafish thrombus model induced by arachidonic acid and FeCl₃. Then, the protein bands of EPF3 incubated with simulated gastric fluid (SGF), simulated intestinal fluid (SIF), and homogenate of Caco-2 cells (HC2C) were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to evaluate its gastrointestinal stability. Finally, the transport behavior and absorption mechanism of EPF3 were studied using Caco-2 cell monolayer. RESULTS: EPF3 could significantly enhance the returned blood volume and blood flow velocity in zebrafish with platelet aggregation thrombus induced by arachidonic acid. It could also prolong the formation time of tail artery thrombus and increase the blood flow velocity in zebrafish with vessel injury thrombus induced by FeCl₃. EPF3 was stable in SIF and HC2C and unstable in SGF. The permeability of EPF3 in Caco-2 monolayer was time-dependent and concentration-dependent. The efflux ratio was less than 1.2 during transport, and the transport behavior was not affected by inhibitors. EPF3 could reversibly reduce the expression of tight junction-related proteins, including zonula occludens-1, occludin, and claudin-1 in Caco-2 cells. CONCLUSION EPF3 could play a thrombolytic and antithrombotic role in zebrafish. It could be transported and absorbed into the intestine through cellular bypass pathway by opening the intestinal epithelium tight junction. This study provides a scientific explanation for the antithrombotic effect of earthworm and provides a basis for the feasibility of subsequent development of EPF3 as an antithrombotic enteric-soluble preparation. Please cite this article as: Zhong WL, Yang JQ, Liu H, Wu YL, Shen HJ, Li PY, Du SY. Antithrombotic effect in zebrafish of a fibrinolytic protein EPF3 from Dilong (Pheretima vulgaris Chen) and its transport mechanism in Caco-2 monolayer through cell bypass pathway. J Integr Med. 2025; 23(4): 415-428.
Animals ; Zebrafish ; Humans ; Caco-2 Cells ; Fibrinolytic Agents/pharmacology* ; Thrombosis/drug therapy* ; Intestinal Absorption

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

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.

Objective:To investigate the correlation between the ratio of apolipoprotein B to apolipoprotein A-I (ApoB/ApoA-I) and unstable carotid plaque in a neurologically healthy population receiving health check-ups.Methods:This cross-sectional study consecutively enrolled 1 149 neurologically healthy individuals who underwent physical examinations at the Health Management Centre of Beijing Tiantan Hospital, Capital Medical University, from October 2021 to September 2022. All eligible participants completed standardized questionnaires, physical examinations and laboratory tests. Laboratory tests of lipid metabolism-related biomarkers included total cholesterol, triglycerides, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), ApoA-I, and ApoB; non-high-density lipoprotein cholesterol and the ApoB/ApoA-I ratio were subsequently calculated. The carotid plaque stability was evaluated using superb microvascular imaging technology. The participants were classified into unstable plaque group (341 cases) and stable plaque group (808 cases) according to the presence or absence of intraplaque neovascularization. The univariate and multivariate logistic regression analyses were used to explore the correlation between the ApoB/ApoA-I ratio and unstable carotid plaques.Results:The study enrolled 1 149 participants totally, with a median age of 57 (49-63) years, including 771 males (67.10%) and 378 females (32.90%), and 341 cases (29.68%) were found with unstable carotid plaques. The unstable plaque group had a higher proportion of males, smoking history, diabetes history, along with higher waist-to-hip ratio and ApoB/ApoA-I ratio compared to the stable plaque group [76.54% vs 63.12%, 33.43% vs 22.77%, 19.06% vs 13.37%, 0.91 (0.85, 0.94) vs 0.89 (0.84, 0.93), 0.64 (0.51, 0.76) vs 0.59 (0.48, 0.72)], while HDL-C and ApoA-I levels were lower [1.39 (1.19, 1.63) vs 1.44 (1.24, 1.66) mmol/L, 1.43 (1.29, 1.60) vs 1.51 (1.36, 1.68) g/L] (all P<0.05). An elevated ApoB/ApoA-I ratio was positively associated with the risk of unstable carotid plaque ( OR=1.61, 95% CI: 1.13-2.29, P=0.008; P for trend<0.001). After adjusting for age, gender, waist-to-hip ratio, history of hypertension, history of diabetes, dyslipidemia, cardiovascular disease, history of smoking and estimated glomerular filtration rate, the positive association between elevated ApoB/ApoA-I ratio and the risk of unstable carotid plaque remained significant ( OR=1.48, 95% CI: 1.01-2.16, P=0.044; P for trend=0.004). Conclusion:In a neurologically healthy population receiving health check-ups, an elevated ApoB/ApoA-I ratio may increase the risk of unstable carotid plaque.