Objective To fabricate a large-diameter vascular graft with a pore size gradient structure mimicking that of natural blood vessels, using poly-L-lactic acid (PLLA) and polycaprolactone (PCL) as base materials through electrospinning and ultrasonic pore-forming techniques, and to evaluate its application potential. Methods A three-layered tubular graft was fabricated from a PCL/PLLA blend (mass ratio 6 : 4) via electrospinning, followed by an ultrasonic pore-forming process to create a gradient porosity. The resulting graft (diameter: 2 cm, length: 4 cm) was implanted into the descending thoracic aorta of an experimental pig using an end-to-end anastomosis. Graft patency and anastomotic sites were monitored by computed tomography angiography (CTA) at 1 and 6 weeks post-surgery. After 2 months, the graft was explanted for systematic evaluation of vascular regeneration and repair through gross examination, histopathology (H&E and elastic fiber staining), immunohistochemistry [for ETS-related gene (ERG), Actin, and Vimentin], and scanning electron microscopy (SEM). Results Postoperative CTA confirmed excellent graft patency at both 1 and 6 weeks, with no evidence of thrombosis or anastomotic stenosis. Gross examination of the 2-month explant revealed a smooth luminal surface covered by neotissue. Histopathological analysis demonstrated that the graft successfully induced the formation of a three-layered structure resembling a native vessel wall, comprising endothelial cells, smooth muscle cells, and fibroblasts. Immunohistochemistry further verified coverage of the luminal surface by endothelial cells (ERG-positive), along with the presence of neosmooth muscle (Actin-positive) and fibroblasts (Vimentin-positive). Endothelial cells were observed adhering to the inner surface of the artificial vessel under SEM. Conclusion The biomimetic, three-layered PLLA/PCL large-diameter vascular graft, constructed via electrospinning and ultrasonic pore-forming, exhibits excellent short-term patency and biocompatibility in a large animal model. More importantly, it demonstrates a significant potential to promote host cell infiltration and achieve in situ regeneration of a three-layered vascular wall structure, providing a promising experimental basis for the development of next-generation functional vascular substitutes.

ObjectiveTo investigate the feasibility， safety， and efficacy of surgery-assisted transjugular intrahepatic portosystemic shunt （SA-TIPS） in the treatment of portal hypertension comorbid with complex portal vein thrombosis， including cavernous transformation of the portal vein （CTPV）. MethodsAn analysis was performed for the data of 36 patients with portal hypertension and complex portal vein thrombosis who underwent SA-TIPS in Beijing Shijitan Hospital， Capital Medical University， from November 2023 to January 2025， including general status， technical data of the surgical process （surgical success rate， puncture times， time of operation， the number of stents used， and the length of shunt）， perioperative complications， and surgical recovery. The change in portal pressure gradient （PPG） after shunt was compared， and the rate of reaching the standard for PPG reduction was calculated， as well as stent patency rate within 1 week after surgery. The paired samples t-test was used for comparison of continuous data between two groups. ResultsAmong the 36 patients， 34 （94.4%） underwent SA-TIPS successfully. The incidence rate of perioperative complications was 16.7% （6/36）， including 3 cases of thoraco-abdominal hemorrhage， 2 cases of intraoperative arrhythmia， and 1 case of incision infection. There was a significant reduction in PPG after SA-TIPS （t=19.85， P<0.01）， and the patients achieving a ≥50% reduction in PPG accounted for 76.5% （26/34）. Imaging reexamination within 1 week showed a shunt patency rate of 100%. ConclusionSA-TIPS has a high technical success rate， a favorable safety profile， and good efficacy in the treatment of portal hypertension comorbid with complex portal vein thrombosis （including CTPV）， and therefore， it holds promise for clinical application.

ObjectiveTo explore the mechanisms of Qingchang Wenzhong Decoction （清肠温中方， QWD） in treating ulcerative colitis （UC）. MethodsA total of 100 male C57BL/6J mice were assigned to a pseudo-germ-free group （n=45） and a conventional group （n=55） using a random number table. Pseudo-germ-free model was established by giving antibiotic treatment and subsequently subjected to acute UC induction. After the model was successfully established， the 45 pseudo-germ-free acute UC mice were randomly allocated to a pseudo-germ-free model group， a pseudo-germ-free QWD group， and a pseudo-germ-free mesalazine group， with 15 mice in each group. The 55 conventional mice were randomly divided into a normal control group （n=10）， as well as a conventional model group， a conventional QWD group， and a conventional mesalazine group， with 15 mice in each group. Except for the normal control group， acute UC models were established in all other groups. Mice in the control group received no intervention. From day 32 of the experiment， mice in the pseudo-germ-free QWD group and the conventional QWD group were administered with QWD granules at a dose of 9.71 g/（kg·d） by gavage with deionized water， while those in the pseudo-germ-free mesalazine group and the conventional mesalazine group were given mesalazine enteric-coated tablets at a dose of 151.67 mg/（kg·d） by gavage. Mice in the remaining groups received an equal volume of deionized water once daily for 7 consecutive days. On day 25 of the experiment， six mice were randomly selected from both the pseudo-germ-free group and the conventional group to measure body weight， and fecal samples were collected for 16S rDNA sequencing to compare differences in gut microbiota， including operational taxonomic units （OTUs）， Shannon index， Observed_species index， and phylogenetic diversity （PD whole tree）. On day 39， body weight was measured in all groups， and the disease activity index （DAI） was evaluated. Colon length and colon wet weight were recorded. Histopathological changes in colonic tissues were assessed by hematoxylin and eosin （HE） staining， and histological injury scores were determined. In addition， the expression levels of mucopolysaccharides and mucin 2 （MUC2） in colonic tissues were measured. ResultsOn day 25， there was no significant difference in body weight between the pseudo-germ-free group and the conventional microbiota group （P＞0.05）. Compared to the conventional microbiota group， the pseudo-germ-free group showed significantly reduced OTUs， Shannon index， Observed_species index， and PD whole tree （P＜0.01）. On day 39， compared to the normal control group， mice in the conventional model group showed a significant decrease in the body weight and an increase in DAI， along with increased colon wet weight， shortened colon length， markedly elevated histopathological scores， and reduced expression of mucopolysaccharides and MUC2 （P＜0.01）. In contrast， no significant differences were observed in these parameters in the pseudo-germ-free model group （P＞0.05）. Compared to the conventional model group， the conventional QWD group showed significant improvement in all measured parameters， whereas the conventional mesalazine group showed reductions only in DAI scores and colon wet weight （P＜0.01）. No statistically significant differences were observed among the pseudo-germ-free model group， the pseudo-germ-free QWD group， and the pseudo-germ-free mesalazine group （P＞0.05）. ConclusionQWD may promote the reconstruction of the intestinal mucus barrier by regulating the intestinal flora， thereby exerting a therapeutic effect on acute UC.

ObjectiveTo explore the mechanisms of Qingchang Wenzhong Decoction （清肠温中方， QWD） in treating ulcerative colitis （UC）. MethodsA total of 100 male C57BL/6J mice were assigned to a pseudo-germ-free group （n=45） and a conventional group （n=55） using a random number table. Pseudo-germ-free model was established by giving antibiotic treatment and subsequently subjected to acute UC induction. After the model was successfully established， the 45 pseudo-germ-free acute UC mice were randomly allocated to a pseudo-germ-free model group， a pseudo-germ-free QWD group， and a pseudo-germ-free mesalazine group， with 15 mice in each group. The 55 conventional mice were randomly divided into a normal control group （n=10）， as well as a conventional model group， a conventional QWD group， and a conventional mesalazine group， with 15 mice in each group. Except for the normal control group， acute UC models were established in all other groups. Mice in the control group received no intervention. From day 32 of the experiment， mice in the pseudo-germ-free QWD group and the conventional QWD group were administered with QWD granules at a dose of 9.71 g/（kg·d） by gavage with deionized water， while those in the pseudo-germ-free mesalazine group and the conventional mesalazine group were given mesalazine enteric-coated tablets at a dose of 151.67 mg/（kg·d） by gavage. Mice in the remaining groups received an equal volume of deionized water once daily for 7 consecutive days. On day 25 of the experiment， six mice were randomly selected from both the pseudo-germ-free group and the conventional group to measure body weight， and fecal samples were collected for 16S rDNA sequencing to compare differences in gut microbiota， including operational taxonomic units （OTUs）， Shannon index， Observed_species index， and phylogenetic diversity （PD whole tree）. On day 39， body weight was measured in all groups， and the disease activity index （DAI） was evaluated. Colon length and colon wet weight were recorded. Histopathological changes in colonic tissues were assessed by hematoxylin and eosin （HE） staining， and histological injury scores were determined. In addition， the expression levels of mucopolysaccharides and mucin 2 （MUC2） in colonic tissues were measured. ResultsOn day 25， there was no significant difference in body weight between the pseudo-germ-free group and the conventional microbiota group （P＞0.05）. Compared to the conventional microbiota group， the pseudo-germ-free group showed significantly reduced OTUs， Shannon index， Observed_species index， and PD whole tree （P＜0.01）. On day 39， compared to the normal control group， mice in the conventional model group showed a significant decrease in the body weight and an increase in DAI， along with increased colon wet weight， shortened colon length， markedly elevated histopathological scores， and reduced expression of mucopolysaccharides and MUC2 （P＜0.01）. In contrast， no significant differences were observed in these parameters in the pseudo-germ-free model group （P＞0.05）. Compared to the conventional model group， the conventional QWD group showed significant improvement in all measured parameters， whereas the conventional mesalazine group showed reductions only in DAI scores and colon wet weight （P＜0.01）. No statistically significant differences were observed among the pseudo-germ-free model group， the pseudo-germ-free QWD group， and the pseudo-germ-free mesalazine group （P＞0.05）. ConclusionQWD may promote the reconstruction of the intestinal mucus barrier by regulating the intestinal flora， thereby exerting a therapeutic effect on acute UC.

[Objective] To explore the effects of different methods on antibody detection through investigating the causes of cross-matching incompatible in a patient with gastric malignant tumor, and to establish flow cytometry protocol for confirming hemolytic transfusion reaction (HTR). [Methods] Antibodies in the patient's serum were identified by red blood cells (RBCs) blood grouping, antibody screening and identification, acid elution test and PEG enhancement test. To confirm HTR, patient RBCs, proximal and distal ends RBCs, separated by capillary centrifugation, were tested by direct antiglobulin test (DAT) and Jk^a antigen single label and double label flow cytometry. [Results] Routine serological technology revealed the presence of anti-C, e (titer:2) and anti-Jka (titer >1) in the patient’s serum. After separation using capillary centrifugation technology, both the proximal and distal DAT and Jk^a antigen tests were negative. Both DAT and Jk^a antigen positive red blood cells (0.21%, 6/6 327) were found in the patient's blood samples by flow cytometry. After separation of blood samples by capillary centrifugation, there were significantly more DAT and Jk^a antigen double-positive RBCs in the distal end (0.43%, 33/7 707) than in the proximal end (0.09%, 15/7 225). Two blood samples were screened from over 100 donor blood samples that are compatible with the patient's cross-matching, and the transfusion effect was favorable. [Conclusion] Serological methods combined with flow cytometry could improve the sensitivity of antibody detection, provide a more accurate basis for the diagnosis of HTRs, and guarantee the safety of blood transfusion.

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

Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

Objective To explore the gender differences and the influence of varus and valgus deformities on distal femur rotational alignment in patients with knee osteoarthritis so as to provide reference for the distal femur rotational osteotomy in total knee arthroplasty(TKA).Methods CT data of 125 knees with osteoarthritis suitable for TKA(including 56 males and 69 females;78 varus knees and 47 valgus knees)were collected and received three-dimensional imaging reconstruction with Mimics software.We measured the posterior condylar angle(PCA),the angle between the anteroposterior axis and the surgical epicondylar axis(ASA),and the angle between the anteroposterior axis and the posterior condylar axis(APA).We also compared gender differences and the influences of varus-valgus deformities on distal femur rotational alignments.Results The PCA and ASA values of distal femur rotational alignments were(3.5±1.1)° vs.(2.8±1.2)°(P=0.001)and(90.6±3.4)° vs.(91.9±3.5)°(P=0.028)for males and females,with statistically differences between the genders.There was no statistically difference in APA between males and females(P=0.482).The PCA values of distal femur rotational alignment in varus and valgus knees were(3.6±1.1)° and(2.9±1.2)°,with a statistically difference between the two groups(P=0.001).There were no statistically differences in ASA or APA between varus and valgus knees(P＞0.05).Conclusion Gender and varus-valgus deformities of knee joint affect the distal femur rotational alignment.Distal femur rotational osteotomy angle should be determined according to the patient's CT imaging before TKA to reduce the errors caused by individual differences and improve the accuracy of the distal femur rotational alignment during TKA.