ObjectiveTo investigate microbial contamination status and distribution characteristics in laboratory animal barrier facilities, so as to provide a scientific basis for environmental quality control in barrier facilities. MethodsIn accordance with the national standard "Laboratory Animals—Environment and Housing Facilities" and the "Standard Operating Procedures" of the barrier facility, bacterial monitoring was performed on samples of air-settling bacteria, materials, and personnel gloves in the single-corridor barrier facility of the Animal Core Facility, Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences (CEMCS). The monitoring data from January 2020 to December 2024 were collected, organized and statistically analyzed, and partial samples were subjected to species identification using PCR and sequencing methods. ResultsA total of 7 898 samples were collected from 2020 to 2024, including 3 175 air-settling bacteria samples, 3 353 material samples, and 1 370 glove samples. The overall compliance rate was 95.7% (7 559/7 898), among which the compliance rate of air-settling bacteria was 97.1% (3 084/3 175), that of materials was 93.2% (3 125/3 353), and that of personnel gloves was 98.5% (1 350/1 370). Over the five years, the compliance rates of all three types of monitored samples were above 90%. There were statistically significant differences in the compliance rates of air-settling bacteria and material samples among different quarters (P<0.05). Further investigation was conducted on samples collected from January to March 2024, and 190 bacterial strains were obtained through isolation and culture, including 126 strains from air-settling bacteria, 52 strains from materials, and 12 strains from personnel gloves. The strains were identified by PCR amplification and sequencing, and the 190 bacterial strains belonged to 9 genera and 20 species. Gram-positive bacteria accounted for the majority, with Staphylococcus as the dominant genus, accounting for 77.9% (148/190). ConclusionMicroorganisms carried by air, materials, and personnel gloves in barrier facilities are mainly Gram-positive bacteria. Regular monitoring of air-settling bacteria, materials, and personnel gloves in barrier facilities enables timely detection and control of potential risks during husbandry management and facility operation, which is of great significance for maintaining the sound operation of the barrier facility system and ensuring the quality of animal experiments.

OBJECTIVE To establish a method for simultaneous determination of plasma concentration of lamotrigine（LTG）， levetiracetam（LEV） and perampanel（PER） in children with epilepsy and apply this method in clinical practice. METHODS Plasma proteins were precipitated with acetonitrile. Using PER-D 5 as internal standard， ultra-high performance liquid chromatography-tandem mass spectrometry （UPLC-MS/MS） method was adopted. The determination was performed on ACQUITY UPLC HSS T3 C 18 column with mobile phase consisted of 0.1% formic acid with 5 mmol/L ammonium acetate-acetonitrile （gradient elution） at the flow rate of 0.3 mL/min. The column temperature was 40 ℃， and sample size was 5 μL. The analysis time was 5 min. The electrospray ionization source and multiple reaction monitoring mode were used for positive ion scanning. The ion pairs used for quantitative analysis of LTG， LEV， PER and internal standard were m / z 255.9→144.9， m / z 171.1→126.1， m / z 350.1→219.0 and m / z 354.9→220.2， respectively. The steady-state trough concentrations of the aforementioned drugs in the plasma of 14 pediatric epilepsy patients receiving combination therapy were determined using the same UPLC-MS/MS method as above. RESULTS The linear ranges of LTG， LEV and PER were 0.15-24 μg/mL （ R 2 ＞0.993）， 0.312 5-50 μg/mL （ R 2 ＞0.997） and 6.25-1 000 ng/mL （ R 2 ＞0.997）， respectively. The lower limits of quantification were 0.15 μg/mL， 0.312 5 μg/mL and 6.25 ng/mL， respectively. RSDs of intraday and interday precision tests of the three drugs were no more than 9.83%， and the accuracies （relative errors） were between －9.33% and 13.72%（ n ＝6 or n ＝18）； the average extraction recovery rates were 86.4%-97.9%， and the average matrix effects were 86.9%-110.0% （ n ＝6）. The absolute values of the relative errors in the stability tests were all below 15%. The steady-state trough concentrations of LTG， LEV and PER were （5.64±4.03）μg/mL， （10.67±8.78）μg/mL and（450.20±251.27）ng/mL， respectively； the rates of achieving target trough concentrations were 71.4%， 37.5% and 84.6%， respectively. CONCLUSIONS The established UPLC-MS/MS method is specific， rapid and suitable for the plasma concentration monitoring in epileptic children receiving combination therapy.

Objective To investigate the effect of postoperative reduction quality in femoral neck fracture internal fixation on mechanical properties of the femoral head from the perspective of trabecular bone biomechanics.Methods From patients who underwent hip replacement surgery for femoral neck fractures,a total of 26 femoral head slice specimens were obtained.The central axis of the primary compressive trabeculae was defined as the 0° group,with the intersection point of the primary compressive trabeculae and the femoral calcar serving as the center.By rotating the specimens to simulate different reduction angles,the cut femoral head slice specimens were randomly divided into five groups:-10°,-5°,0°,5°,and 10°,representing femoral heads with varying reduction qualities.The specimens were subjected to single compression load tests and fatigue load tests.The load was set from 70 N to 1 400 N,at a frequency of 1 Hz,with 10 000 cycles.Axial stiffness,displacement,and the number of collapse cycles were measured,to compare the biomechanical properties of femoral head specimens under different reduction qualities.Results There were differences in the axial stiffness,displacement,and number of collapse cycles among the femoral head specimens in different groups.Under 800 N load,the axial stiffness of 0° group was significantly greater than that of±10° groups(P＜0.05).The axial stiffness of 0° group was also greater than that of the±5° groups,but the differences were not statistically significant(P＞0.05).The axial stiffness of±5° groups was greater than that of±10° groups(P＜0.05).0° group had a lower displacement than±5° groups and±10° groups.However,the differences in displacement between 0° group and±5° groups were not statistically significant(P＞0.05),while the differences between the 0° group and±10° groups were statistically significant(P＜0.05).The differences in displacement between±5° groups and±10° groups were also statistically significant(P＜0.05).0° group had a significantly higher number of collapse cycles than±10° groups(P＜0.05).The number of collapse cycles in 0° group was also higher than that in±5° groups,but the differences were not statistically significant(P＞0.05).The number of collapse cycles in±5° groups was significantly higher than that±10° groups(P＜0.05).Conclusions The quality of reduction after internal fixation of femoral neck fractures significantly affects the biomechanical properties of the femoral head.This study provides a scientific basis for optimizing treatment and postoperative management,aiming to improve clinical outcomes and patients' quality of life.

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 investigate the effects of goal-directed fluid therapy(GDFT)combined with ultrasound-guided erector spinae plane block(ESPB)on perioperative stress response and postoperative recovery in patients undergoing robot-assisted pedicle screw fixation surgery.Methods Eighty patients scheduled for elec-tive surgery were randomly divided into two groups:control(general anesthesia+conventional fluid management,n=40)and intervention(general anesthesia+GDFT+ESPB,n=40).Heart rate(HR),mean arterial pressure(MAP),serum cortisol(Cor),norepinephrine(NE),blood glucose(GLU)levels,and resting VAS scores were measured and compared between the two groups preoperatively(T?),at screw placement(T?),at end of surgery(T?),30 minutes after extubation(T?),at 24 hours(T?),and 48 hours(T?)postoperatively.Intraoperative fluid volume,remifentanil consumption,postoperative rescue analgesia frequency,time to first ambulation,length of stay,and complications(agitation,nausea and vomiting,respiratory depression)were recorded.Results There were no differences in baseline(T?)indicators between the two groups(P>0.05).The intervention group exhibited significantly lower levels of HR,MAP,Cor,NE,and GLU at T?,T?,and T? compared with the control group(P<0.05),with Cor,NE,and GLU reduced by>30%at T?(P<0.05).Intraoperative fluid volume and remi-fentanil dosage were significantly reduced(both P<0.05).VAS scores and the number of rescue analgesia requests were lower at T?,T?,and T?(P<0.01).Time to first ambulation time and postoperative hospital stay were shortened(both P<0.01).The incidence of agitation,nausea/vomiting and overall complications was lower in the interven-tion group(P<0.05),whereas respiratory depression rates did not differ(P>0.05).Conclusion GDFT plus ESPB can effectively suppress perioperative stress response in robot-assisted spinal surgery,significantly reduce intraoperative opioid dosage and fluid volume,optimize postoperative analgesia,enhance recovery,and lower complication risk.This combination provides an effective ERAS strategy for improving surgical safety and recovery quality.

Objective·To evaluate the predictive value of anti-neutrophil cytoplasmic antibodies(ANCA)in Kawasaki disease(KD)complicated with coronary artery lesions(CALs)and to construct a nomogram prediction model.Methods·A retrospective study was conducted to collect the clinical data of 340 children with KD admitted to Shanghai Children's Medical Center from January 2018 to May 2024.All patients were randomly divided in a 7:3 ratio into a training set(n=237)and a validation set(n=103).Univariate analysis and least absolute shrinkage and selection operator(LASSO)were applied to screen the risk factors of CALs,which were incorporated into multifactorial Logistic regression analysis to develop the nomogram model.The model's discrimination,calibration and clinical practicability were evaluated using the receiver operating characteristic(ROC)curve,calibration curve,Hosmer-Lemeshow goodness-of-fit test,and decision curve analysis(DCA).A new predictive scoring system was obtained by assigning scores to each variable based on the coefficients of the independent variables in the Logistic regression equation,and its predictive efficacy was then compared with that of three commonly used scoring systems,Kobayashi,Egami,and Sano scoring models.Results·Male,low serum albumin level,ANCA positivity,and intravenous immunoglobulin resistance were risk factors for the development of CALs in children with KD,based on which a nomogram model was constructed.The area under the ROC curve for the nomogram in the training set and validation set were 0.747(95%CI 0.667?0.821)and 0.645(95%CI 0.500?0.794),respectively,indicating good effectiveness.The model was verified to have good predictive accuracy through the calibration curve and Hosmer-Lemeshow goodness-of-fit test(training set:χ2=5.105,P=0.746;validation set:χ2=13.549,P=0.094).The DCA showed its clinical usefulness.A predictive scoring system for CALs was developed based on the coefficients of the Logistic regression equation,which demonstrated higher sensitivity(58.4%)and specificity(78.7%)compared to the Kobayashi,Egami,and Sano scoring models.Conclusion·This study developed a new scoring model based on ANCA to effectively predict the risk of CALs in KD patients.The model provides valuable reference for clinicians to identify high-risk patients early,and to formulate personalized treatment plans and management strategies.

Aim To explore the mechanism of ligustil-ide(LIG)improving demyelination by inhibiting in-flammatory response in mice with distal middle cerebral artery occlusion(dMCAO)through AIM2/caspase-1 signal pathway.Methods Thirty C57BL/6N male mice were randomly divided into three groups:sham operation group(Sham group,n=10),model group(dMCAO group,n=10)and treatment group(LIG group,n=10).The dMCAO mouse model was estab-lished by electrocoagulation in dMCAO group and LIG group.The mice were scored by Longa after waking up,and the changes of cerebral blood flow were moni-tored by laser speckle blood flow imaging system after dMCAO.One hour after modeling,LIG(30 mg·kg-1·d-1)was injected intraperitoneally in LIG group,and the same amount of normal saline was injected in sham group and dMCAO group for one week until the end of the experiment.The mice in each group were stained with TTC,and the brain injury was observed pathologically.Fatigue turning bar test and open field test were used to evaluate the motor function and anxie-ty degree of mice,and then the brain tissues of mice were taken for black gold staining to compare the chan-ges of myelin sheath in each group.Immunofluores-cence staining was used to detect the average fluores-cence intensity of MBP,IBA1 and GFAP in CC,CPU and CX regions of mouse brains.ELISAwas used to de-tect the contents of TNF-α,IL-6,IL-1 β,IL-17A and BDNF in brain tissue proteins of mice.Western blot-ting was used to detect the protein expressions of AIM2,caspase-1 and ASC-in each group.Results Compared with the dMCAO group,the infarct area was reduced,the behavior was significantly improved and the demyelination was reduced in the LIG group.The expression of MBP protein in CC,CPU and CX regions increased(P＜0.05),the expression of IBA1 in CX decreased(P＜0.01),and the expression of GFAP in-creased in CC,CPU and CX regions(P＜0.01).The results of ELISA showed that the levels ofTNF-α(P＜0.01),IL-6(P＜0.01),IL-1β(P＜0.05)and IL-17A(P＜0.01)significantly decreased,while the ex-pression of BDNF increased(P＜0.05).The protein expression levels of AIM2,caspase-1 and ASC in mouse brain decreased after treatment(P＜0.01).Conclusion LIG has a protective effect on demyelina-tion in dMCAO mice,which may be related to the inhi-bition of AIM2/caspase-1 signaling pathway and in-flammation and to the promotion of BDNF secretion.

Objective·To identify relevant biomarkers for patients with coronavirus disease 2019-associated kidney injury(COVID-19-associated KI)and explore the mechanisms underlying the involvement of severe acute respiratory syndrome coronavirus-2(SARS-CoV-2)proteins in infection-related KI by affecting the interactions between renal cells and macrophages.Methods·A retrospective analysis was conducted on the clinical characteristics of COVID-19 patients with KI treated in Shanghai Ninth,People's,hospital from December 2022 to February 2023.Serum levels of inflammatory factors and chemokines were measured by using enzyme-linked immunosorbent assay(ELISA).In vitro,human macrophage cell line THP-1 cells were stimulated with recombinant S1 subunit protein derived from SARS-CoV-2 spike protein.The cells and culture supernatants were collected to detect the levels of inflammatory factors and chemokines by using quantitative real-time PCR(qRT-PCR)and ELISA.Conditioned medium was prepared from the cell culture supernatants of S1-stimulated THP-1 cells and used to stimulate human renal epithelial cells(HK-2)in vitro to assess cytokine secretion.Antibody blocking experiments were performed to analyze the effects of the conditioned medium on the production of cytokines in HK-2 cells.Results·Among 39 patients with COVID-19,8(20.50%)had creatinine levels above the reference interval,which indicated the occurrence of KI.The levels of peripheral tumor necrosis factor-α(TNF-α)in the COVID-19 patient with KI group[(18.33±8.20)pg/mL]were significantly higher than those in the non-KI group[(11.88±6.50)pg/mL](P=0.015).In vitro assay has shown that S1-spike protein stimulation promoted the level of gene transcription and production of TNF-α,interleukin-1β(IL-1β)and chemokine C-X-C motif ligand 10(CXCL10)in THP-1 macrophage cells(P＜0.001).Furthermore,the conditioned medium from S1-stimulated THP-1 cells promoted the secretion of TNF-α,IL-1β and CXCL10 by HK-2 cells(P=0.005).When anti-TNF-α antibody(Infliximab)was used to block TNF-α in the culture supernatants from S1-stimulated THP-1 cells,the secretion level of TNF-α by HK-2 cells decreased dramatically(P＜0.001).Conclusion·TNF-α levels increase significantly in COVID-19 patients with KI,implying the significance of TNF-α in the occurrence of COVID-19-associated KI.In vitro experiments confirm that the S1 protein induces TNF-α secretion from THP-1 cells,leading to increased inflammatory responses in renal cells,which may contribute to the development of COVID-19-associated KI.Therefore,targeting TNF-α may become an alternative strategy to reduce the occurrence of COVID-19-associated KI.

Aim To investigate the neuroprotective effect of Takeda G protein-coupled receptor-5(TGR5)activated by INT-777 on hypoxic-ischemic encephalop-athy(HIE)in neonatal rats.Methods Seven-day-old SD rats were randomly divided into the sham opera-tion group(Sham,S),model group(HIE,G),INT-777 low-dose(L),medium-dose(M),and high-dose(H)groups.The modified Rice-Vanucci method was used to construct the HIE model and Intranasal admin-istration 1 h after modeling.Short-term neurobehavioral tests were performed 48 h after modeling to evaluate the neurological function of neonatal rats,TTC staining was used to determine the volume of cerebral infarction,dry and wet specific gravity was used to determine the brain water content,ferrous ion kit was used to deter-mine the brain ferrous ion content,HE staining was used to observe the pathological damage of brain tis-sue,Nissl staining was used to observe the loss of Nissl substance,Transmission electron microscopy(TEM)was used to observe the mitochondrial morphological changes of cortical neurons,and Western blot was em-ployed to detect the expression of ferroptosis-related proteins TFR1 and GPX4.Results Compared with group S,group G had increased short-term neurobehav-ioral test consumption time,higher scores,increased cerebral infarct volume,brain water content,and brain ferrous iron content,significant brain tissue damage on the affected side,severe loss of Nissl substance,smaller neuronal mitochondria,decreased mitochondrial cris-tae,and increased expression of TFR1 and reduced ex-pression of GPX4.Compared with group G,the INT-777 administration group had a shorter consumption time for short-term neurobehavioral tests,lower scores,the cerebral infarction volume,brain water content,and brain ferrous ion content decreased,the brain tissue damage on the affected side was reduced,and there was insignificant loss of Nissl substance,larger neuronal mi-tochondrial volume,increased mitochondrial cristae,re-duced expression of TFR1,and increased expression of GPX4.Conclusions INT-777 agonist TGR5 has a protective effect against hypoxic-ischemic encephalopa-thy in neonatal rats,and its mechanism of action may be related to the inhibition of neuronal ferroptosis.

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.