OBJECTIVE To compare the efficacy and safety of evolocumab and probucol in patients with ultra-high-risk atherosclerotic cardiovascular disease （ASCVD） following percutaneous coronary intervention （PCI）. METHODS A retrospective analysis was conducted on 156 ultra-high-risk ASCVD patients who underwent PCI in our institution between January 1， 2023 and December 31， 2024. According to the lipid-lowering regimen， the patients were categorized into evolocumab group （ n ＝86） and probucol group （ n ＝70）. Changes in lipid parameters [total cholesterol （TC）， low-density lipoprot ein cholesterol （LDL-C）， high-density lipoprotein cholesterol （HDL-C）， triglycerides， lipoprotein （a）， and lipid goal achievement rate ] ， inflammatory markers [interleukin-6 （IL-6） and C-reactive protein （CRP） ] ， and cardiac function indices （left ventricular ejection fraction， left ventricular end-systolic diameter， left ventricular end-diastolic diameter， and N-terminal pro-B-type natriuretic peptide） were compared between two groups at baseline and after 6 months of treatment. The incidence of adverse clinical events during treatment， including acute myocardial infarction， in-stent restenosis， acute heart failure， cerebral hemorrhage， and stroke， was also evaluated. RESULTS No statistically significant differences were observed between the two groups at baseline （ P ＞0.05）. After 6 months of treatment， both groups demonstrated significant improvements in lipid profiles （except HDL-C） and inflammatory markers compared to those at baseline （ P ＜0.05）. The evolocumab group exhibited greater reductions in TC， LDL-C， IL-6， and CRP， along with a higher lipid target achievement rate， compared with the probucol group （ P ＜0.05）. There were no statistically significant differences in the cardiac function-related indicators before and after treatment between the two groups， nor in the incidence of adverse events during the treatment （ P ＞0.05）. CONCLUSIONS For ultra-high-risk ASCVD patients after PCI， both of the above treatment options are associated with improvements in blood lipid and inflammatory response， with good safety during short-term follow-up. Evolocumab shows superior efficacy in TC， LDL-C and inflammatory markers reduction and lipid target achievement， compared to probucol.

With the continuous deepening of the concept of precision diagnosis and treatment for lung cancer, how to achieve higher efficiency and accuracy in the screening, diagnosis, and treatment pathways in clinical practice has become an important issue that urgently needs to be overcome. The current clinical difficulty lies in the fact that despite continuous advancements in imaging and molecular diagnostic technologies, there are still limitations in manual efficiency and subjective experience when it comes to massive data analysis and multi-scale feature extraction. Artificial intelligence (AI), especially algorithm systems based on deep learning, is an innovative technology capable of deeply empowering medical big data. This method utilizes algorithms such as convolutional neural networks, combined with radiomics, pathomics, and multi-modal data fusion analysis, demonstrating immense potential in early precise detection and benign-malignant differentiation of pulmonary nodules, digital pathological subtype recognition and non-invasive prediction of driver genes, precise 3D surgical planning and automatic delineation of radiotherapy target volumes, as well as dynamic risk warning during follow-up. This innovative technology provides a brand-new solution for realizing intelligent and individualized lung cancer diagnosis and treatment models. This consensus, based on the latest evidence from evidence-based medicine and combined with the development trends in the AI field and real-world clinical needs, was ultimately formed by gathering the consensus opinions of multidisciplinary experts in radiology, pathology, thoracic surgery, and other fields. The main content covers the application specifications of AI in the three core scenarios of lung cancer screening, diagnosis, and treatment, the technical standards for data collection and algorithm validation, as well as the ethical and regulatory challenges faced at the current stage. It aims to clarify the applicable boundaries of AI as a clinical auxiliary decision support tool, providing scientific guidance and standardized exploration directions for peers currently engaged in or planning to carry out AI-assisted clinical diagnosis, treatment, and translation of lung cancer.

Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.

Objective:To explore the application value of integrated Chinese and western medicine in the treatment of sepsis-induced coagulopathy (SIC) induced by bacterial pneumonia sepsis.Methods:A total of 60 inpatients with bacterial pneumonia and sepsis admitted to the Dongzhimen Hospital of Beijing University of Chinese Medicine from October 2023 to June 2024 were collected in a cross-sectional study. Serum samples were collected, and immune indexes, coagulation function and some laboratory test results of the patients were detected or recorded. Sepsis Associated Sequential Organ Failure Assessment (SOFA) score and Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ) score were evaluated.Results:Among the 60 patients, 71.7%( n=43) were associated with coagulation disorder, 65%( n=39) showed hemorrhagic SIC; A total of 37 patients (61.7%) were treated with integrated traditional Chinese and western medicine, and 23 patients (38.3%) were treated with Western medicine. The main types of syndrome differentiation were toxic-heat syndrome ( n=48, 80.0%) and blood-stasis syndrome ( n=11, 18.3%). Serum human monocyte chemoattractant protein-1 (MCP-1) and platelet count (PLT) in patients with blood stasis syndrome were significantly lower than those in toxic-heat syndrome (all P<0.05). In patients with bacterial pneumonia sepsis, the total score of syndrome of excess of fu-viscera (Fu-shi-zheng) was positively correlated with programmed death ligand-1 (PD-L1) ( r=0.293, P=0.023) and tumor necrosis factor-α (TNF-α) ( r=0.436, P=0.001). The total score of toxin-heat syndrome ( r=0.323, P=0.016) and excess of fu-viscera syndrome ( r=0.354, P=0.008) were positively correlated with prothrombin time (PT). PD-1 was positively correlated with SOFA score ( r=0.343, P=0.007) and APACHE Ⅱ score ( r=0.354, P=0.006). The PD-1 level and SOFA and APACHE Ⅱ scores of the patients treated with integrated Chinese and western medicine were significantly lower than those treated with Western medicine alone (all P<0.05). Conclusions:The combined intervention of traditional Chinese medicine and Western medicine based on " Fuzheng Touxie Jiedu (The method of strengthening the body and removing the toxin)" has strong clinical guiding significance, and can effectively improve the immune function and prognosis of bacterial pneumonia SIC.

Objective:To analyze the effect of joint management of type 2 diabetes mellitus (T2DM) between specialty and community under the model of National Diabetes Prevention and Control Center (DPCC).Methods:A total of 2 527 T2DM patients managed by DPCC Pingshan Center of Shenzhen from January 1, 2022 to December 31, 2024 were retrospectively included. After management, the rate of downturn, reexamination rate, blood pressure compliance rate, metabolic indicators (waist circumference, body mass index, fasting blood glucose, glycosylated hemoglobin, blood lipids) and screening rate of chronic complications of diabetes (atherosclerotic cardiovascular disease, microvascular disease, diabetic peripheral neuropathy) were analyzed. Those included 2022 ( n=564), 2023 ( n=1 477), and 2024 ( n=2 527). Results:The downturn rate in 2022, 2023 and 2024 increased year by year (22.8% vs 67.2% vs 89.9%, P<0.01), and the review rate (41.1% vs 62.2% vs 52.7%, P<0.01), complication screening rate (51.6% vs 85.3% vs 62.2%, P<0.01), blood pressure compliance rate (53.1% vs 78.0% vs 67.2%, P<0.01), body mass index compliance rate (13.2% vs 17.3% vs 28.6%, P<0.01), fasting blood glucose meeting rate (46.4% vs 60.2% vs 68.5%, P<0.01), glycated hemoglobin meeting rate (58.4% vs 63.2% vs 45.6%, P<0.01) were relatively improved. Waist circumference compliance rate (30.6% vs 27.7% vs 21.6%) and blood lipid compliance rate (33.6% vs 35.5% vs 31.9%) were not significantly improved, and the review rate, blood pressure compliance rate and complication screening rate in 2024 were lower than those in 2023 and higher than those in 2022. Conclusions:The combined management of type 2 diabetes under the DPCC model has significant effects on improving the down-conversion rate, rediagnosis rate, blood pressure compliance rate, metabolic index compliance rate and the screening rate of diabetes-related chronic complications in patients with diabetes. At the same time, it was also found that with the progress of hierarchical diagnosis and treatment, the review rate, complication screening rate, blood pressure, waist circumference, blood lipid and glycosylated hemoglobin reached the standard of patients decreased compared with the previous situation, which needs to be further analyzed and improved.

Objective:To investigate the impact of postoperative complications on adverse outcomes following curative-intent resection for gallbladder cancer (GBC).Methods:The multi-center real-world study was conducted. The clinicopathological data of 629 patients with GBC, who were admitted to 14 medical centers including The First Affiliated Hospital of Army Medical University from the national multicenter database of Biliary Surgery Group of Elite Group of Chinese Journal of Digestive Surgery, from April 2020 to April 2024 were collected. There were 225 males and 404 females, aged (64±10)years. Patients underwent open curative-intent resection for GBC. Observation indicators: (1)surgery, postoperative complica-tions and adverse outcomes; (2) analysis of risk factors affecting postoperative adverse outcomes in patients and population attributable fraction (PAF). Missing data in predictor variables were addressed using multiple imputation with chained equations, while cases with missing outcome variables were addressed using the "multiple imputation then deletion (MID)" strategy. The severity of multicollinearity among independent variables was assessed using the variance inflation factor (VIF) test. Multivariable possion regression models with log link and robust error variance were construc-ted incorporating restricted cubic splines (3 knots) to address nonlinear relationships in continuous variables, calculating adjusted relative risk ( RR) with corresponding 95% confidence interval ( CI). Adjusted PAF was calculated for each imputed dataset using the AF package of R software, with subsequent pooling performed according to Rubin's rules. Results:(1) Surgery, postoperative complications and adverse outcomes. All 629 patients underwent curative-intent resection for GBC, of which 143 cases had postoperative complications, including 68 cases of intra-abdominal ascites, 39 cases of pulmonary infection, 21 cases of bile leakage, 12 cases of intra-abdominal hemorrhage, 11 cases of liver failure, 10 cases of pan-creatic fistula, 10 cases of wound infection, 10 cases of gastroparesis, 7 cases of cholangitis, 7 cases of sepsis. The same patient could have more than one kind of complication. Of 629 patients, there were 19 cases of postoperative 90-day death and 11 cases of missing data, 42 cases with post-operative 90-day reoperation and 7 cases with missing data, 44 cases with postoperative 90-day readmission and 3 cases with missing data, 155 cases with prolonged postoperative hospital stay and 3 cases with missing data. (2) Analysis of risk factors affecting the postoperative adverse outcomes in patients and PAF. Results of multivariate analysis showed that pulmonary infection and liver failure were independent risk factors for postoperative 90-day mortality ( RR=3.74, 12.15, 95% CI as 1.18-11.83, 1.98-74.48, P<0.05). Pulmonary infection demons-trated the highest PAF as 4.61% (95% CI as 3.94%-5.28%, P<0.05). Intra-abdominal ascites, pulmonary infection, bile leakage, and intra-abdominal hemorrhage were independent risk factors for post-operative 90-day reoperation ( RR=4.80, 3.62, 3.46, 4.99, 95% CI as 2.49-9.26, 1.42-9.21, 1.34-8.92, 1.55-16.06, P<0.05). Intra-abdominal ascites demonstrated the highest PAF as 8.65% (95% CI as 8.22%-9.08%, P<0.05). Intra-abdominal ascites, bile leakage, and liver failure were independent risk factors for postoperative 90-day readmission ( RR=6.20, 3.33, 14.33, 95% CI as 3.21-11.95, 1.33-8.35, 3.72-55.28, P<0.05). Intra-abdominal ascites demonstrated the highest PAF as 9.11% (95% CI as 8.85%-9.37%, P<0.05). Intra-abdominal ascites, pulmonary infection, bile leakage, liver failure, and wound infection were independent risk factors for prolonged postoperative hospital stay ( RR=2.29, 2.21, 2.26, 2.14, 3.35, 95% CI as 1.63-3.23, 1.41-3.46, 1.32-3.86, 1.11-4.13, 1.70-6.60, P<0.05). Intra-abdominal ascites demonstrated the highest PAF as 6.03% (95% CI as 5.71%-6.35%, P<0.05). Conclusion:Pulmonary infection is the most significant risk factor for postoperative 90-day mortality after curative-intent resection for GBC, while intra-abdominal ascites is the most significant risk factor for postoperative 90-day reoperation, postoperative 90-day readmission, and prolonged postoperative hospital stay.

Objective:To investigate the completion rate of tumor evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients in the national multicenter real-world database.Methods:The prospective real-world study was conducted. The clinicopathological data of 1 074 patients who underwent surgical treatment for mid and low rectal cancer in 47 national medical institutions, including Peking Union Medical College Hospital et al, from May 12,2023 to May 11,2024 were collected. Observation indicators: (1) clinical characteristics of patients with mid and low rectal cancer; (2) initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer; (3) initial imaging evaluation of patients with mid and low rectal cancer; (4) imaging evaluation after neoadjuvant therapy for patients with mid and low rectal cancer. Measurement data with normal distribution were represented as Mean± SD, and measurement data with skewed distribution were represented as M( Q1, Q3). Count data were described as absoluter numbers and/or percentages. Results:(1) Clinical characteristics of patients with mid and low rectal cancer. Of the 1 074 patients, there were 713 males and 361 females, aged 63(56,70)years. The body mass index of 1 074 patients was 24(21,26)kg/m 2.For American Society of Anesthesiologists classification, there were 147 cases of stage Ⅰ, 641 cases of stage Ⅱ, 157 cases of stage Ⅲ, 2 cases of stage Ⅳ, and there were 127 cases missing data. (2) Initial colonoscopy and pathologic evaluation of tumors in patients with mid and low rectal cancer. Of the 1 074 patients, there were 787 cases (73.28%) undergoing complete colonoscopy, and there were only 197 cases (18.34%) undergoing immunohistochemical evaluation of all four mismatch repair proteins. (3) Initial imaging evaluation of patients with mid and low rectal cancer. Of the 1 074 patients, there were 842(78.40%) patients completing magnetic resonance imaging (MRI) or ultrasound evaluation, and there were 914(85.10%) patients completing chest, abdomen, and pelvis enhanced computed tomography (CT) evaluation. In the 149 patients completing rectal ultrasound evaluation, there were 122 cases (81.88%) comple-ting T staging evaluation, and there were 81 cases (54.36%) completing N staging evaluation. In the 808 patients completing rectal MRI evaluation, there were 708 cases (87.62%) completing T staging evaluation, and there were 590 cases (73.02%) completing N staging evaluation. (4) Imaging evalua-tion after neoadjuvant therapy for patients with mid and low rectal cancer. Of the 388 patients with neoadjuvant therapy, there were 332 patients (85.57%) completing MRI or ultrasound evaluation, and there were 327 patients (84.28%) completing chest, abdomen, and pelvis enhanced CT evalua-tion. In the 70 patients completing rectal ultrasound evaluation, there were 65 cases (92.86%) com-pleting T staging evaluation, and there were 49 cases (70.00%) completing N staging evaluation. In the 327 patients completing rectal MRI evaluation, there were 246 cases (75.23%) completing T staging, and there were 228 cases (69.72%) completing N staging evaluation. Conclusion:The com-pletion rate of tumor imaging evaluation at initial assessment and after neoadjuvant therapy for mid and low rectal cancer patients on a national scale is relatively good.

Background and purpose:The Shanghai Municipal Center for Disease Control and Prevention provides annual updates on cancer statistics in Shanghai.Breast cancer is one of the common malignant tumors among women.In recent years,the incidence of female breast cancer was increasing,while its trend of mortality showed declining.This study aimed to investigate the survival rates of new female breast cancer cases in Shanghai from 2002 to 2017.Methods:Data of new cases and deaths of female breast cancer patients with follow-up information from 2002 to 2017 were obtained from the Population-based Cancer Registry and Vital Statistics System of Shanghai Municipal Center for Disease Control and Prevention.Numbers,proportions,and survival rates were stratified by year of diagnosis,age,histological type and stage at diagnosis for analysis.The 5-year observed survival rates were calculated based on the life table method.The probabilities of surviving from 0 to 99 years were estimated with the Elandt-Johnson model,and then cumulative expected survival rates were calculated using the Ederer Ⅱ method.Finally,the 5-year relative survival rates were calculated.The annual percent change(APC)of survival rates was estimated by Joinpoint Regression Program.Results:A total of 73 600 new female breast cancer cases were diagnosed from 2002 to 2017 in Shanghai.Among them,67 681 cases were morphological verification,accounting for 91.96%.By December 31,2022,23 745(32.26%)cases had died,and 19 466(26.45%)cases had died of cancer.A total of 68 332(92.84%)cases,who were either dead or followed for over 5 years,were considered to have complete follow-up.The remaining 5 268(7.16%)cases were lost to follow-up.73 538(99.92%)cases were included in the observed cohort for survival analysis.The number of observed cases nearly doubled from 3330 in 2002 to 6095 in 2017.The 5-year observed survival rate changed from 78.77%in 2002 to 84.55%in 2017 dynamically,showed a low increasing trend with an average rate of 0.50%per year(APC=0.50%,t=8.75,P＜0.001).The 5-year relative survival rate also increased from 83.46%to 89.24%slowly,with an average rate of 0.47%(APC=0.47%,t=9.80,P＜0.001).The overall 5-year observation survival rate of female cancer was 83.24%(82.96%-83.52%),and the 5-year relative survival rate was 87.58%(87.29%-87.87%)in Shanghai from 2002 to 2017.It was increasing over time,decreasing with aging and advanced stage at diagnosis continuously.There was no significant difference in the 5-year relative survival rates between the groups aged 15 to 64(P＞0.05).The group with an unknown stage had the highest number of cases,followed by the stage Ⅱ group,and then the stage Ⅰ group.The 5-year relative survival rate of cases with stage Ⅰ disease reached 99.10%(98.78%-99.42%),but these cases only accounted for 25.51%of the total.The 5-year relative survival rate of cases with stage Ⅳ disease was 52.54%(50.98%-54.11%),and these cases accounted for 6.13%of the total.The 5-year relative survival rate of cases with s unknown stage was 82.04%(81.42%-82.65%),and these cases accounted for 31.05%of the total.Conclusion:The diagnostic levels and survival rates of female breast cancer in Shanghai were relatively high and continue to improve.However,the proportions of cases with unknown histological type and unknown stage remain relatively high,and the proportion of stage Ⅰ cases is not very large.The survival rates of stage Ⅳ cases are relatively low.This study provides evidence for further research,prevention and control efforts for female breast cancer.

Aim To study whether intravenous injec-tion of miR-129-3p mimetic(agomir)can resist bone loss caused by hind limb disuse,and to provide new i-deas for preventing bone loss in microgravity environ-ment.Methods Forty-eight C57BL/6J male mice were randomly divided into the control group(CON),tail suspension model group(TS),tail suspension+miR-129-3p agomir administration group(miRNA)and tail suspension+miR-129-3p negative sequence agomir control group(NC).The miRNA group was given 4 mg·kg-1 miR-129-3p agomir by intravenous injection into the medial canthus twice a week.The NC agomir group were consistent with those in the miR-129-3p agomir group,and the CON and TS groups were given only equal volumes of normal saline.After four weeks,all mice were sacrificed and samples were collected.Micro-CT scan of femur,three-point femur bending test,serum bone metabolism index detection,oxidative stress index detection and osteogenesis-related protein expression analysis in bone tissue were per-formed.Results After four weeks,the number of tra-becular bone in the TS group was significantly re-duced,and Tb.BMD,Tb.Th,Tb.N,Tb.BS/TV and Tb.BV/TV were significantly lower than those in the CON group(P＜0.01).While Tb.Sp TS group was significantly higher than the CON group(P＜0.05),the maximum load and flexural strength of the femur significantly decreased(P＜0.01),the content of ser-um bone formation index PINP was significantly lower than that of the CON group(P＜0.01),and the con-tent of bone resorption index CTX-I was significantly higher than that of the CON group(P＜0.01),the content of serum oxidative damage indexes 8-iso-PGF2α and 8-OHdG significantly increased(P＜0.01),and the expression of osteogenesis-related pro-teins in bone tissue markedly decreased(P＜0.01).However,the increase or decrease of all indexes in miRNA group was significantly lower than that in TS group.Conclusions miR-129-3p mimetic can signifi-cantly reduce bone loss caused by hind limb disuse.This experiment provides a new idea and method for preventing bone loss in microgravity environment.

Objective To develop and validate an efficient and simple liquid chromatography with tandem mass spectrometry(LC-MS/MS)method for determination of polymyxin E in human plasma,and apply the established method in therapeutic drug monitoring(TDM)of polymyxin E.Methods The LC-MS/MS platform was based on AB SCIEX HPLC-4500MD system.Gradient elution was performed with 0.2％formic acid in water and 0.2％formic acid in acetonitrile.Phenomenex Kinetex XB-C18 column(100 mm × 2.1 mm,2.6 μm)were used.The analytes were detected by electrospray ionization(ESI)positive multiple reaction monitoring mode.The ion pairs for analytes(polymyxins E1,E2)and internal standard(polymyxins B1)were m/z 390.7→101.3,m/z 386.0→101.2,and m/z 402.3→101.2,respectively.Plasma samples were processed with protein precipitation method.Results Polymyxin E1 and E2 showed good linearity in the range of 0.031 2-6.24 mg/L and 0.006 15-1.23 mg/L,respectively.The within-run accuracy of polymyxin E1 and E2 in plasma ranged from 89.4％to 99.8％and 91.5％to 108.2％,respectively,while the between-run accuracy ranged from 91.8％to 104.7％and 95.6％to 105.2％,respectively.The within-run precision of polymyxin E1 and E2 in plasma ranged from 4.9％to 8.9％and 2.8％to 8.5％,respectively,while the between-run precision ranged from 4.1％to 7.6％and 4.2％to 9.8％,respectively.The average internal standard normalized matrix effect factors of polymyxins E1 and E2 were 96.9％-111.2％and 106.1％-112.8％in blank plasma samples from 6 different sources,102.5％-106.8％and 98.8％-105.2％in lipemic plasma,respectively,107.8％-108.9％and 106.9％-1 07.4％in hemolyzed plasma,respectively.The precision of matrix effects was less than 15.0％.The average recovery rate was 102.9％-107.5％for polymyxin E1 and E2,and 107.0％for internal standard polymyxin B1.The precision was less than 3.7％.Conclusions In this study,a simple and efficient LC-MS/MS method was established for determination of polymyxin E1 and E2 in human plasma,which is reliable in the therapeutic drug monitoring and pharmacokinetic study of polymyxin E.