Introduction: Severe hypertriglyceridemia during pregnancy is a rare yet potentially life-threatening disorder. It is frequently linked to acute pancreatitis and poses considerable risks for both maternal and fetal morbidity. Case: We report a 35-year-old G4P3 female at 33 + 6 weeks gestation with underlying type 2 diabetes mellitus who presented with acute abdominal pain, nausea, vomiting, and poor oral intake, initially mistaken for preterm labor and sepsis. Further evaluation revealed profound hypertriglyceridemia (triglycerides 79.1 mmol/L) with markedly elevated total cholesterol (>32 mmol/L) and raised serum amylase, consistent with hypertriglyceridemia-induced acute pancreatitis. She was managed in a multidisciplinary setting with intravenous insulin infusion, dextrose supplementation, aggressive fluid resuscitation, and empiric antibiotics. Due to clinical deterioration and ongoing risk of maternal complications, she underwent emergency lower segment caesarean section and exploratory laparotomy at 34 weeks of gestation. Intraoperative findings included inflammatory intra-abdominal fluid and a bulky pancreas, supporting the diagnosis. Rapid biochemical improvement was observed following treatment, with triglyceride levels decreasing by approximately 70% within 24 hours (79.1– 24.0 mmol/L) and achieving >90% reduction over 10 days. Postpartum management included initiation of omega-3 fatty acids, fibrate, and statin therapy, resulting in sustained lipid control. Ophthalmologic examination demonstrated lipemia retinalis, further confirming severe dyslipidemia. Conclusion This case highlights the importance of early recognition of severe hypertriglyceridemia in pregnancy, particularly in patients with metabolic risk factors such as diabetes. Prompt initiation of insulin therapy can achieve rapid triglyceride reduction and may obviate the need for plasmapheresis in selected cases. Delivery should be considered in the setting of maternal instability. Long-term lipid management postpartum is essential for preventing recurrence and reducing future metabolic risk. A multidisciplinary approach remains critical in optimizing both maternal and fetal outcomes in this rare but serious condition.
Female ; Pregnancy ; Acute Disease ; Pancreatitis

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.

Lung cancer poses a serious threat to global public health security.Chemotherapy,as the main strategy for cancer treatment,faces challenges such as high toxicity and drug resistance.Anticancer peptides have the potential of being developed into new anticancer drugs due to their advantages of broad-spectrum anticancer activity,rapid action,and difficulty in generating drug resistance,but they also face shortcomings such as weak activity and strong toxic side effects.The weakly acidic microenvironment of tumors(pH 6.5-6.8)provides a good idea for the design of anticancer peptides of high-efficiency and low-toxicity.Previously,we designed the acid-sensitive antibacterial peptide pHly-1 using the wolf spider(Lycosa singoriensis)toxin Lycosin-Ⅰ as a template.In this study,we found that pHly-1 also had acid-sensitive anticancer activity.Further alanine scanning analysis of pHly-1 was carried out,and we ob-tained a mutant pHTP-2 with better acid sensitivity,whose IC50(half maximal inhibitory concentration)against A549 cells was 15.68 μmol/L at pH 6.6 and was greater than 100 μmol/L at pH 7.4.At pH 6.6,pHTP-2 could act on various lung cancer cell lines and induce the death of A549 cells by rapid ly-sis;at pH 7.4,500 μmol/L pHTP-2 had weak toxicity to red blood cells(the hemolysis rate was ap-proximately 38％)and primary myocardial cells(the inhibition rate was 49.7％,with P＜0.05).Analy-sis of its charge,particle size,morphology,and secondary structure showed that at pH 6.6,the histidine in the sequence of pHTP-2 was protonated,increasing the positive charge(P＜0.01),decreasing the hy-drated particle size(P＜0.05)and forming an α-helical structure to induce membrane lysis of A549 cells.At pH 7.4,it was deprotonated,the positive charge decreases,a β-sheet structure was formed and self-aggregation occurred,limiting its effect on the A549 cell membrane and showing weak activity.In summary,pHTP-2 could respond to the weakly acidic microenvironment of tumors to exert selective cyto-toxic activity,effectively overcoming the shortcomings of anticancer peptides such as low efficiency and high toxicity.Our findings suggest that it is a high-quality lead molecule for anticancer drugs.

AIM To study the effects of Jiaotai Pills and their single composition drugs on high-fat diet-induced hypothalamic inflammation in obese mice.METHODS C57BL/6J mice were randomly divided into the normal group(15 mice)and the high-fat group(75 mice).The mice given 12 weeks of high-fat diet feeding were further randomly divided into the model group,the Jiaotai Pills group,the Coptis chinensis group,the Cinnamomum cassia group and the positive metformin group,with 15 mice in each group.After 6 weeks of administration,the mice had their body weight and fasting blood glucose(FBG)levels detected;their hypothalamic expressions of IL-1β,IL-6,TNF-α and Socs3 mRNA detected by RT-qPCR;their hypothalamic expressions of TLR4,MyD88,IKKβ and activated NF-κB protein detected by Western blot;their hypothalamic expressions of Iba1 and GFAP detected by immunohistochemistry;and their ultrastructural changes of nerve tissues observed using transmission electron microscopy(TEM).RESULTS Compared with the model group,each drug group displayed decreased hypothalamic expressions of IL-1β,IL-6,TNF-α and Socs3 mRNA(P＜0.01),and improved number and morphology of nerve cells revealed by TEM.The groups intervened with Jiaotai Pills,or Coptis chinensis,or metformin shared decreased body weight and FBG levels(P＜0.05);decreased protein expressions of TLR4,MyD88,IKKβ and p-NF-κB(P＜0.05);and decreased number of hypothalamic astrocytes and microglia(P＜0.05).Additionally,decreased p-NF-κB protein expression was observed in the Cinnamomum cassia group(P＜0.05).CONCLUSION Jiaotai Pills and their single composition drugs can improve high-fat diet-induced hypothalamic inflammation in obese mice.

Objective:To analyze the symptoms,diagnosis and treatment of upper urinary tract calculi patients combined with mild and moderate benign prostatic hyperplasia(BPH)after ureteral stent implantation.Methods:One hundred and six BPH pa-tients who were hospitalized for upper urinary tract calculi and had ureteral stents retained from January 2019 to December 2022 were selected and divided into 2 weeks group and 4 weeks group according to the time of removal of ureteral stents after surgery.Their gener-al clinical data were analyzed and compared.International Prostatic Symptom Scale(IPSS),postoperative ureteral Stent Symptom Questionnaire(USSQ),and incidence of adverse events after ureteral stent removal were recorded before and after removal.Results:The scores of IPSS were significantly increased in all patients,and symptoms in urinary tract had improved significantly after discharge(P＜0.05).Compared with the 2 weeks group,the USSQ score of the 4 weeks group was significantly increased(P＜0.05).And no significant adverse event was observed in the 2 weeks group after the removal of ureteral sten.Conclusion:IPSS score and USSQ score increased significantly during stent implantation in BPH patients with lithiasis.And complications increased sig-nificantly over time.Following thorough clinical assessment,early ureteral stent removal demonstrates both safety and efficacy,repre-senting an optimal therapeutic approach in selected cases.

Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91％of the total clinical isolates and 4.07％of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89％were isolated from children and 33.11％were isolated from adults.More than 90％of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79％in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06％were isolated from children and 19.94％isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0％.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.

AIM To study the effects of Jiaotai Pills and their single composition drugs on high-fat diet-induced hypothalamic inflammation in obese mice.METHODS C57BL/6J mice were randomly divided into the normal group(15 mice)and the high-fat group(75 mice).The mice given 12 weeks of high-fat diet feeding were further randomly divided into the model group,the Jiaotai Pills group,the Coptis chinensis group,the Cinnamomum cassia group and the positive metformin group,with 15 mice in each group.After 6 weeks of administration,the mice had their body weight and fasting blood glucose(FBG)levels detected;their hypothalamic expressions of IL-1β,IL-6,TNF-α and Socs3 mRNA detected by RT-qPCR;their hypothalamic expressions of TLR4,MyD88,IKKβ and activated NF-κB protein detected by Western blot;their hypothalamic expressions of Iba1 and GFAP detected by immunohistochemistry;and their ultrastructural changes of nerve tissues observed using transmission electron microscopy(TEM).RESULTS Compared with the model group,each drug group displayed decreased hypothalamic expressions of IL-1β,IL-6,TNF-α and Socs3 mRNA(P＜0.01),and improved number and morphology of nerve cells revealed by TEM.The groups intervened with Jiaotai Pills,or Coptis chinensis,or metformin shared decreased body weight and FBG levels(P＜0.05);decreased protein expressions of TLR4,MyD88,IKKβ and p-NF-κB(P＜0.05);and decreased number of hypothalamic astrocytes and microglia(P＜0.05).Additionally,decreased p-NF-κB protein expression was observed in the Cinnamomum cassia group(P＜0.05).CONCLUSION Jiaotai Pills and their single composition drugs can improve high-fat diet-induced hypothalamic inflammation in obese mice.

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.