OBJECTIVE To investigate the effects of subanesthetic dose of esketamine on postoperative anxiety and recovery in patients undergoing laparoscopic cholecystectomy. METHODS A total of 200 patients scheduled for laparoscopic cholecystectomy at Suzhou Ninth Hospital Affiliated to Soochow University from January 2023 to December 2024 were randomly assigned to control group （n＝100） and observation group （n＝100）. One minute before the initiation of anesthesia， patients in the control group received intravenous injections of Propofol emulsion injection， Sufentanil citrate injection， and Succinylcholine chloride injection. On this basis， patients in the observation group received an intravenous injection of Esketamine hydrochloride injection. The anxiety status of patients in both groups was compared， along with their general intraoperative conditions （including sufentanil dosage， duration of pneumoperitoneum， operative time， anesthesia time， and extubation time）， postoperative recovery， incidence of adverse reactions， and the need for dezocine rescue analgesia. Heart rate and mean arterial pressure， entropy index （state entropy and response entropy）， inflammatory marker levels [interleukin-6 （IL-6） and C-reactive protein （CRP）]， numerical rating scale （NRS） for pain intensity were compared between the two groups at different time points. RESULTS No significant differences were found between the two groups in pneumoperitoneum duration， operative time， anesthesia time，extubation time， incidence of postoperative dry mouth， entropy index or length of stay in the post-anesthesia care unit （P＞0.05）. Compared with the control group， the observation group showed significantly lower postoperative STAI-S scores， reduced intraoperative sufentanil consumption， decreased incidence of postoperative nausea， vomiting， and shivering， the need for dezocine rescue analgesia， as well as lower plasma IL-6 and CRP levels at 24 h after surgery， and NRS （P＜0.05）. The heart rate and mean arterial pressure of patients in the observation group at the start of surgery， end of surgery， and during extubation were all significantly higher than those in the control group （P＜0.05）. CONCLUSIONS Subanesthetic dose of esketamine can effectively alleviate postoperative anxiety， reduce intraoperative opioid consumption， suppress postoperative inflammatory response， relieve postoperative pain， and promote recovery in patients undergoing laparoscopic cholecystectomy.

OBJECTIVE To establish a quantitative analysis of multi-components by single-marker （QAMS） method for simultaneous determination of six flavonoids and two phenolic acids in Perilla frutescens leaves using scutellarin and rosmarinic acid as internal reference substances， and apply this method to determine the contents of eight components in 20 batches of P. frutescens leaves samples from different regions. METHODS Scutellarin served as the internal reference to calculate relative correction factors （RCFs） for scutellarin-7-O-diglucuronide， luteolin-7-O-diglucuronide， apigenin-7-O-diglucuronide， luteolin-7-O- β-D-glucuronide and apigenin-7-O-glucuronide. Rosmarinic acid was employed as the internal reference to determine the RCF for caffeic acid. The contents of the above flavonoids and phenolic acids were calculated with QAMS， and compared with the results of external standard method. RESULTS The eight analytes demonstrated excellent linearity within their respective concentration ranges （r≥0.999 0）. The mean recovery rates for spiked samples ranged from 95.60% to 102.15%， with relative standard deviations （RSDs） of 0.72% to 2.70% （n＝6）. The method exhibited good precision， repeatability， and stability （RSD＜2.50%， n＝6）. Variations in instruments， columns， column temperature， flow rate， and formic acid volume fraction had minimal impact on the RCFs （RSD＜3%， n＝3）. Comparison with the external standard method showed no significant differences in the content of each component across batches， except for caffeic acid in the ZS12 batch （absolute value of RE＜5%， n＝2）. The contents of six CARS-21） flavonoid components in P. frutescens leaves samples varied significantly across different geographic origins， while the content of total flavonoids showed no significant difference. In contrast， the contents of two phenolic acid components and total phenolic acid exhibited significant variation among samples from different regions. CONCLUSIONS The developed QAMS method can simultaneously determine the contents of six flavonoids and two phenolic acids in P. frutescens leaves. It is convenient for detection， highly accurate， and cost-effective. This method is suitable for the quality control of P. frutescens leaves， and the variation of flavonoid and phenolic acid content in samples from different regions provides a reference for the selection of optimal cultivation areas.

Objective To investigate the functional changes of dendritic cells(DCs)in patients at different stages of hepatitis B virus(HBV)infection and analyze the mechanisms underlying DC dysfunction.Methods Single-cell RNA sequencing dataset GSE182159 was downloaded from the GEO database and classified into healthy control(HC),immune active(IA),and immune tolerant(IT)groups based on infection stage.Peripheral blood samples were collected from 7 IA patients,7 IT patients,and 12 healthy controls.Flow cytometry was used to isolate classical dendritic cells(cDC)and plasmacytoid dendritic cells(pDC).The expression levels of transcription factors in cDC and pDC were measured by quantitative real-time PCR(qRT-PCR).Bioinformatics analyses were per-formed using R and Python package.Results The proportions of DCs in IA and IT groups were higher than that in HC group.Func-tional enrichment analysis revealed that the differentially expressed genes(DEGs)of cDCs in the IA group were primarily enriched for the processes,such as inflammatory response,MHC classⅡantigen processing and presentation,cell migration,signal transduction,metabolism,and immune response.In contrast the IT group exhibited lower enrichment intensity and a significant reduction in interfer-on responses.The DEGs of pDC in the IA group were enriched in the processes of MHC-Ⅱantigen presentation,Fc receptor signal transduction,and metabolism,whereas those in the IT group were showed enrichment only in Fc receptor signal transduction and me-tabolism with a lower intensity.Both groups exhibited reduced synthesis of typesⅠandⅡinterferons in pDC,with the IT group showing a more pronounced downregulation.Cell-cell communication analysis demonstrated enhanced interactions between myeloid cells(except pDC)and T cells in the IA group,whereas the interactions between cDC/pDC and T cells in the IT group were reduced.Transcription factor analysis revealed that STAT2,STAT3,IRF1,and IRF5 were highly expressed in the IA group but their expression exhibited low-er expression levels in the IT group.In contrast,BHLHE40 was broadly upregulated in both cDC and pDC subsets within the IT group.The qRT-PCR results were consistent with the findings from the single-cell transcription factor analysis.Conclusion The IT phase of hepatitis B infection represents a critical period for cDC dysfunction,characterized by significant suppression of MHCⅡantigen presen-tation,metabolism,and interferon responsiveness.The functional impairment of pDC precedes that of cDC,as evidenced by a marked downregulation of interferon synthesis capacity observed during the IA phase.

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:This study aims to investigate the expression of uridine diphosphate-glucose[]pyrophos-phorylase 2(UGP2)in breast cancer(BC)tissues and its oncogenic mechanism,assessing its potential value as a diag-nostic and prognostic biomarker for breast cancer.Methods:(1)Online database analysis was conducted to assess UGP2 mRNA and protein expression levels in breast cancer and explore their correlation with clinical characteristics.Im-munohistochemistry(IHC)was used to verify UGP2 expression in human breast cancer tumor tissues and evaluate its relationship with clinicopathological features.(2)Kaplan-Meier survival analysis and COX regression models were used to analyze the impact of UGP2 expression on breast cancer patient prognosis.(3)Bioinformatics methods were em-ployed to investigate the correlation between UGP2 and tumor immune cell infiltration,and to predict the biological func-tions and associated signaling pathways of UGP2 in breast cancer.Results:(1)The mRNA and protein expression levels of UGP2 were upregulated in breast cancer tissues(both P<0.05),and were negatively correlated with ER-positive and PR-positive status(OR<1,P<0.05),while positively correlated with Ki-67 levels and the triple-negative breast cancer(TNBC)subtype(OR>1,P<0.05).(2)Elevated expression levels of UGP2 were associated with poorer survival rates in breast cancer patients(both P<0.05)and were identified as an independent adverse prognostic factor for breast cancer(HR=1.40,P<0.05).(3)Functional analysis results suggested that UGP2 may promote tumor progression by regulating metabolism,hormone signaling,and the immune microenvironment.Additionally,UGP2 expression was negatively cor-related with NK cell activation status and positively correlated with the inhibitory state.Conclusion:UGP2 expression is elevated in breast cancer tissues and is closely associated with poor patient prognosis.It may promote cancer pro-gression through mechanisms such as metabolic reprogramming and immune suppression.UGP2 shows promise as a potential biomarker and therapeutic target in breast cancer,providing a basis for personalized treatment.

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.

Objective:To compare the efficacy of different doses of tranexamic acid (TXA) for traumatic hemorrhagic shock (THS) in the early phase of trauma following acute exposure to high altitude in rabbits.Methods:Twenty-five healthy male New Zealand rabbits were randomly divided into plain control group ( n=5) and acute high-altitude THS group ( n=20) according to the random number table method. The plain control group did not undergo THS modeling throughout the experiment while the acute high-altitude THS group was raised in a hypoxia simulation chamber with a volume fraction of 10% for 3 days to establish the THS model. Based on the different doses of TXA administered intravenously at 30 minutes after THS modeling, the acute high-altitude THS group was further divided into four subgroups: acute high-altitude THS+0 mg/kg TXA subgroup, acute high-altitude THS+45 mg/kg TXA subgroup, acute high-altitude THS+90 mg/kg TXA subgroup and acute high-altitude THS+135 mg/kg TXA subgroup, with 5 rabbits in each. The vital signs [mean arterial pressure (MAP), heart rate, rectal temperature] and blood cell counts [red blood cell count (RBC), platelet count (PLT)], 4 coagulation parameters [fibrinogen (FIB), D-dimer, activated partial thromboplastin time (APTT), prothrombin time (PT)], thromboelastography [clotting reaction time (R value), clot formation time (K value), maximum amplitude (MA value)], syndecan-1, inflammatory factors [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)], and plasminogen activator inhibitor-1 (PAI-1) were recorded before blood loss, at 30 minutes and 120 minutes after blood loss. At 6 hours after THS, the lungs, terminal ileum, and kidneys of the rabbits were collected to observe tissue damage, and the wet/dry weight ratio (W/D) and total water content (TLW) of the lung tissue were measured. Results:(1) Vital signs: Before blood loss, there were no significant differences in MAP, heart rate, or rectal temperature between the acute high-altitude THS subgroups and the plain control group ( P>0.05). At 30 minutes and 120 minutes after blood loss, the acute high-altitude THS subgroups exhibited significantly lower MAP, heart rate, and rectal temperature compared to those in the plain control group ( P<0.05). No significant differences were observed in MAP, heart rate or rectal temperature among the acute high-altitude THS subgroups at any time point ( P>0.05). In the acute high-altitude THS subgroups, MAP, heart rate and rectal temperature were significantly decreased at 30 minutes and 120 minutes after blood loss compared to those before blood loss ( P<0.05); At 120 minutes after blood loss, these parameters were further significantly decreased compared to those at 30 minutes after blood loss ( P<0.05). (2) Blood cell counts: Before blood loss, the RBC count was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while the PLT was significantly lower ( P<0.05). At 30 minutes after blood loss, there was no significant difference in RBC count between the acute high-altitude THS subgroups and the plain control group ( P>0.05), but the PLT remained significantly lower in the acute high-altitude THS subgroups ( P<0.05). At 120 minutes after blood loss, the RBC count was significantly lower in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), with no significant differences among the acute high-altitude THS subgroups ( P>0.05). The PLT count was significantly lower in the acute high-altitude THS+0 mg/kg TXA subgroup compared to the other subgroups ( P<0.05). The PLT count in the acute high-altitude THS+45 mg/kg TXA subgroup was significantly lower than those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant differences between the latter two subgroups ( P>0.05). (3) Four Coagulation parameters: Before blood loss, D-dimer level was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant difference was observed in FIB ( P>0.05). APTT and PT were significantly shortened in the acute high-altitude THS subgroups ( P<0.05). At 30 minutes after blood loss, D-dimer level remained significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while FIB was significantly lower ( P<0.05), with significant increase of APTT and PT compared to those before blood loss ( P<0.05). At 120 minutes after blood loss, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly higher D-dimer level compared to the other subgroups ( P<0.05), with significantly lower FIB and higher APTT and PT ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup also showed significantly higher D-dimer level compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with significantly lower FIB and increased APTT and PT ( P<0.05). No significant differences were observed in D-dimer, FIB, APTT or PT between the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P>0.05). (4) Thromboelastography parameters: Before blood loss, the R value was significantly shorter in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant differences were observed in K value or MA value ( P>0.05). At 30 minutes after blood loss, both R value and K value were significantly shorter in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05), with no significant differences in MA value ( P>0.05). At 120 minutes after blood loss, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly increased R value and K value compared to those in the other subgroups ( P<0.05), while MA value was significantly decreased ( P<0.05). The remaining acute high-altitude THS subgroups showed significant decrease of R value and K value compared to those in the plain control group ( P<0.05), while MA value was significantly lower ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup exhibited significantly lower R value and K value compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant differences in R value, K value and MA value between the later two groups ( P<0.05). (5) Changes in Syndecan-1, inflammatory factors and PAI-1: Before blood loss, syndecan-1 was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant differences were observed in IL-6, TNF-α, or PAI-1 ( P>0.05). At 30 minutes after blood loss, syndecan-1, IL-6, TNF-α, and PAI-1 were significantly higher in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05). At 120 minutes after blood loss, syndecan-1, IL-6, TNF-α, and PAI-1 were significantly higher in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05). Among them, the acute high-altitude THS+0 mg/kg TXA group exhibited significantly higher levels of syndecan-1, IL-6, TNF-α, and PAI-1 compared to the other acute high-altitude THS subgroups ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup had significantly higher syndecan-1, IL-6, and TNF-α compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant difference in PAI-1 ( P>0.05). No significant differences were observed in syndecan-1, IL-6, TNF-α or PAI-1 between the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P>0.05). (6) Tissue injury: At 6 hours after THS, acute high-altitude THS+0 mg/kg TXA group exhibited significant interstitial thickening of the lung with extensive inflammatory cell infiltration, localized loss of intestinal brush border accompanied by cellular disruption, and marked structural disruption of renal corpuscles with focal cellular injury and necrosis. At 6 hours after THS, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly higher lung injury scores, Chiu′s intestinal injury scores, and kidney injury scores compared to those of the other subgroups ( P<0.05). No significant differences were observed in the tissue injury scores of the lungs, intestines and kidneys among the other subgroups ( P>0.05). The acute high-altitude THS+0 mg/kg TXA subgroup also had significantly higher lung W/D and TLW compared to those in the other subgroups ( P<0.05). At 6 hours after THS, the acute high-altitude THS+45 mg/kg TXA group exhibited significantly higher W/D and TLW of the lung tissues compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA groups ( P<0.05), with no significant differences between the latter two subgroups ( P>0.05). Conclusions:At 3 days after acute exposure to high altitude, rabbits show a hypercoagulable state of the blood, accompanied by endothelial barrier dysfunction. At 30 minutes after the induction of acute high-altitude THS, a single slow intravenous bolus injection of TXA at doses of 90 mg/kg and 135 mg/kg is more effective in improving coagulation and fibrinolysis function, inflammatory response, endothelial injury, and reduced the risk of pulmonary edema than that at a dose of 45 mg/kg.

Objective To observe the effects of general anesthesia with remazolam on electrophysiological monitoring indicators and cerebral oxygen saturation(ScO2)in patients undergoing carotid endarterectomy(CEA).Methods Patients who underwent elective CEA from July 2022 to June 2024 in neurosurgery department of our hospital were randomly divided into the ramazolam group(R group)and the propofol group(P group).Patients in both groups were given propofol 1.5 to 2.0 mg/kg,cisatracurium 0.1 to 0.2 mg/kg,and sufentanil 0.3 to 0.4 μg/kg for anesthesia induction.Anesthesia maintenance:patients in the R group received intravenous infusion of remifentanil 0.5 to 1.0 mg·kg-1·h-1,while patients in the P group received intravenous infusion of propofol 5.0 to 7.0 mg·kg-1·h-1.Both groups received intravenous infusion of remifentanil 0.1 to 0.2 μg·kg-1·min-1 for anesthesia maintenance.The operation time,carotid artery occlusion time,intraoperative infusion volume,remifentanil and norepinephrine dosage,and awakening time of patients in the two groups were recorded.The hemodynamic and cerebral oxygen indicators,amplitude and latency of evoked potentials before anesthesia(T0),after anesthesia(T1),5 minutes before blockade(T2),5 minutes after blockade(T3),5 minutes after unblocking(T4)and at the end of surgery(T5)of patients in the two groups were observed and compared,and the total incidence of postoperative complications was followed up and calculated.Results Compared with the P group,the dosage of intraoperative norepinephrine of patients in the R group was reduced(P<0.05),and the awakening time was shortened(P<0.05).At T2,the average arterial pressure(MAP)of patients in the R group was higher than that in the P group(P<0.05).At T3,the ScO2 of patients in the R group was significantly higher than that in the P group,and the percentages of prolonged latency and decreased amplitude of motor evoked potentials(MEP)were significantly lower than those in the P group(P<0.05),the percentage of decreased amplitude of lower limb somatosensory evoked potentials(SSEP)was lower than that in the P group(P<0.05);At T5,the MEP amplitude of patients in the R group was significantly increased compared to that at T2,while the MEP amplitude of patients in the P group was significantly decreased compared to that at T2,and the differences were statistically significant(P<0.05).There was no statistically significant difference in the total incidence of postoperative complications between the two groups(P>0.05).Conclusion As a general anesthesia maintenance drug,remazolam can achieve satisfactory anesthesia effects for CEA,with more stable intraoperative hemodynamics,and less impact on ScO2 and evoked potential monitoring during carotid artery occlusion compared to propofol,resulting in higher safety.

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 compare the efficacy of different doses of tranexamic acid (TXA) for traumatic hemorrhagic shock (THS) in the early phase of trauma following acute exposure to high altitude in rabbits.Methods:Twenty-five healthy male New Zealand rabbits were randomly divided into plain control group ( n=5) and acute high-altitude THS group ( n=20) according to the random number table method. The plain control group did not undergo THS modeling throughout the experiment while the acute high-altitude THS group was raised in a hypoxia simulation chamber with a volume fraction of 10% for 3 days to establish the THS model. Based on the different doses of TXA administered intravenously at 30 minutes after THS modeling, the acute high-altitude THS group was further divided into four subgroups: acute high-altitude THS+0 mg/kg TXA subgroup, acute high-altitude THS+45 mg/kg TXA subgroup, acute high-altitude THS+90 mg/kg TXA subgroup and acute high-altitude THS+135 mg/kg TXA subgroup, with 5 rabbits in each. The vital signs [mean arterial pressure (MAP), heart rate, rectal temperature] and blood cell counts [red blood cell count (RBC), platelet count (PLT)], 4 coagulation parameters [fibrinogen (FIB), D-dimer, activated partial thromboplastin time (APTT), prothrombin time (PT)], thromboelastography [clotting reaction time (R value), clot formation time (K value), maximum amplitude (MA value)], syndecan-1, inflammatory factors [interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)], and plasminogen activator inhibitor-1 (PAI-1) were recorded before blood loss, at 30 minutes and 120 minutes after blood loss. At 6 hours after THS, the lungs, terminal ileum, and kidneys of the rabbits were collected to observe tissue damage, and the wet/dry weight ratio (W/D) and total water content (TLW) of the lung tissue were measured. Results:(1) Vital signs: Before blood loss, there were no significant differences in MAP, heart rate, or rectal temperature between the acute high-altitude THS subgroups and the plain control group ( P>0.05). At 30 minutes and 120 minutes after blood loss, the acute high-altitude THS subgroups exhibited significantly lower MAP, heart rate, and rectal temperature compared to those in the plain control group ( P<0.05). No significant differences were observed in MAP, heart rate or rectal temperature among the acute high-altitude THS subgroups at any time point ( P>0.05). In the acute high-altitude THS subgroups, MAP, heart rate and rectal temperature were significantly decreased at 30 minutes and 120 minutes after blood loss compared to those before blood loss ( P<0.05); At 120 minutes after blood loss, these parameters were further significantly decreased compared to those at 30 minutes after blood loss ( P<0.05). (2) Blood cell counts: Before blood loss, the RBC count was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while the PLT was significantly lower ( P<0.05). At 30 minutes after blood loss, there was no significant difference in RBC count between the acute high-altitude THS subgroups and the plain control group ( P>0.05), but the PLT remained significantly lower in the acute high-altitude THS subgroups ( P<0.05). At 120 minutes after blood loss, the RBC count was significantly lower in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), with no significant differences among the acute high-altitude THS subgroups ( P>0.05). The PLT count was significantly lower in the acute high-altitude THS+0 mg/kg TXA subgroup compared to the other subgroups ( P<0.05). The PLT count in the acute high-altitude THS+45 mg/kg TXA subgroup was significantly lower than those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant differences between the latter two subgroups ( P>0.05). (3) Four Coagulation parameters: Before blood loss, D-dimer level was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant difference was observed in FIB ( P>0.05). APTT and PT were significantly shortened in the acute high-altitude THS subgroups ( P<0.05). At 30 minutes after blood loss, D-dimer level remained significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while FIB was significantly lower ( P<0.05), with significant increase of APTT and PT compared to those before blood loss ( P<0.05). At 120 minutes after blood loss, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly higher D-dimer level compared to the other subgroups ( P<0.05), with significantly lower FIB and higher APTT and PT ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup also showed significantly higher D-dimer level compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with significantly lower FIB and increased APTT and PT ( P<0.05). No significant differences were observed in D-dimer, FIB, APTT or PT between the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P>0.05). (4) Thromboelastography parameters: Before blood loss, the R value was significantly shorter in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant differences were observed in K value or MA value ( P>0.05). At 30 minutes after blood loss, both R value and K value were significantly shorter in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05), with no significant differences in MA value ( P>0.05). At 120 minutes after blood loss, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly increased R value and K value compared to those in the other subgroups ( P<0.05), while MA value was significantly decreased ( P<0.05). The remaining acute high-altitude THS subgroups showed significant decrease of R value and K value compared to those in the plain control group ( P<0.05), while MA value was significantly lower ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup exhibited significantly lower R value and K value compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant differences in R value, K value and MA value between the later two groups ( P<0.05). (5) Changes in Syndecan-1, inflammatory factors and PAI-1: Before blood loss, syndecan-1 was significantly higher in the acute high-altitude THS subgroups compared to that in the plain control group ( P<0.05), while no significant differences were observed in IL-6, TNF-α, or PAI-1 ( P>0.05). At 30 minutes after blood loss, syndecan-1, IL-6, TNF-α, and PAI-1 were significantly higher in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05). At 120 minutes after blood loss, syndecan-1, IL-6, TNF-α, and PAI-1 were significantly higher in the acute high-altitude THS subgroups compared to those in the plain control group ( P<0.05). Among them, the acute high-altitude THS+0 mg/kg TXA group exhibited significantly higher levels of syndecan-1, IL-6, TNF-α, and PAI-1 compared to the other acute high-altitude THS subgroups ( P<0.05). The acute high-altitude THS+45 mg/kg TXA subgroup had significantly higher syndecan-1, IL-6, and TNF-α compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P<0.05), with no significant difference in PAI-1 ( P>0.05). No significant differences were observed in syndecan-1, IL-6, TNF-α or PAI-1 between the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA subgroups ( P>0.05). (6) Tissue injury: At 6 hours after THS, acute high-altitude THS+0 mg/kg TXA group exhibited significant interstitial thickening of the lung with extensive inflammatory cell infiltration, localized loss of intestinal brush border accompanied by cellular disruption, and marked structural disruption of renal corpuscles with focal cellular injury and necrosis. At 6 hours after THS, the acute high-altitude THS+0 mg/kg TXA subgroup exhibited significantly higher lung injury scores, Chiu′s intestinal injury scores, and kidney injury scores compared to those of the other subgroups ( P<0.05). No significant differences were observed in the tissue injury scores of the lungs, intestines and kidneys among the other subgroups ( P>0.05). The acute high-altitude THS+0 mg/kg TXA subgroup also had significantly higher lung W/D and TLW compared to those in the other subgroups ( P<0.05). At 6 hours after THS, the acute high-altitude THS+45 mg/kg TXA group exhibited significantly higher W/D and TLW of the lung tissues compared to those in the acute high-altitude THS+90 mg/kg TXA and acute high-altitude THS+135 mg/kg TXA groups ( P<0.05), with no significant differences between the latter two subgroups ( P>0.05). Conclusions:At 3 days after acute exposure to high altitude, rabbits show a hypercoagulable state of the blood, accompanied by endothelial barrier dysfunction. At 30 minutes after the induction of acute high-altitude THS, a single slow intravenous bolus injection of TXA at doses of 90 mg/kg and 135 mg/kg is more effective in improving coagulation and fibrinolysis function, inflammatory response, endothelial injury, and reduced the risk of pulmonary edema than that at a dose of 45 mg/kg.