Objective:To develop and validate a clinical prediction model for assessing the risk of postoperative pulmonary complications (PPCs) in elderly patients undergoing surgery with general anesthesia.Methods:This prospective observational study enrolled patients aged ≥65 years who underwent general anesthesia with mechanical ventilation duration >3 hours across six tertiary hospitals between December 2022 and August 2023. Based on follow-up outcomes (until discharge or postoperative day 7), patients were categorized into a non-PPCs group and a PPCs group. Detailed records included baseline patient characteristics, preoperative comorbidities, surgical information (type, duration), and bedside lung ultrasound scores (LUS) assessed within 24 hours postoperatively using a standardized 12-zone protocol. Predictor selection was performed using LASSO regression. Significant predictors identified were incorporated into a multivariate logistic regression analysis to build the prediction model, visualized as a nomogram. Internal validation was conducted via bootstrap resampling (1 000 repetitions). Model performance was evaluated using the area under the receiver operating characteristic curve (AUC) for discrimination, calibration curves for calibration accuracy, and decision curve analysis (DCA) for clinical utility.Results:A total of 130 eligible elderly surgical patients were included. PPCs occurred in 17 patients (incidence rate: 13.1%). Multivariate analysis identified LUS ( OR=1.248, 95% CI: 1.099-1.417, P=0.001) and elective surgery type ( OR=0.206, 95% CI: 0.043-0.988, P=0.048) as independent predictors of PPCs. The nomogram model demonstrated an AUC of 0.867 (95% CI: 0.775-0.959) upon initial testing. Internal validation confirmed good discrimination (AUC=0.863, 95% CI: 0.778-0.972). Calibration curves indicated excellent agreement between predicted probabilities and observed outcomes. Decision curve analysis demonstrated significant clinical net benefit across a wide range of threshold probabilities (0.03-0.89). Conclusions:The clinical prediction model, developed using early postoperative LUS scores and surgical type, effectively predicts the risk of postoperative pulmonary complications in elderly patients following surgery under general anesthesia. The model exhibits strong discrimination, calibration, and clinical utility, providing clinicians with a reliable tool for individualized risk assessment to support clinical decision-making and potentially reduce PPC incidence.

Objective:To investigate the role of calcium-binding protein S100A9 in acute lung injury induced by hepatic ischemia-reperfusion (HIR) in mice, and to explore its relationship with nuclear factor erythroid 2-related factor 2 (Nrf2).Methods:A total of 12 specific pathogen-free (SPF) male wild-type (WT) and 12 S100A9 knockout (S100A9 KO) C57BL/6J mice aged 6~8 weeks and weighing 20-25 g were randomly divided into four groups using a random number table: WT+Sham group, S100A9 KO+Sham group, WT+HIR group, and S100A9 KO+HIR group ( n=6 per group). The HIR model was established by clamping the portal vein and hepatic artery of the left and median liver lobes for 60 minutes followed by reperfusion. At 6 hours post-reperfusion, mice were anesthetized again, and blood samples were collected from the inferior vena cava. Both lungs were harvested. The lung wet-to-dry (W/D) weight ratio was measured. Hematoxylin and eosin (HE) staining was used to assess histopathological changes and calculate lung injury scores. The levels of inflammatory markers—S100A9, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) —as well as oxidative stress indicators including myeloperoxidase (MPO), reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD) in serum and lung tissue were measured. Western blotting was used to assess the expression levels of nuclear and cytoplasmic Nrf2, and cytoplasmic HO-1. Results:Compared with the WT+Sham group, both the WT+HIR and S100A9 KO+HIR groups showed significantly increased lung injury scores, W/D ratio, TNF-α, IL-6, ROS, MPO, and MDA levels (all P<0.05). Compared with the WT+HIR group, the S100A9 KO+HIR group exhibited significantly reduced levels of these indicators (all P<0.05). Moreover, the S100A9 KO+HIR group showed elevated nuclear Nrf2 expression and decreased cytoplasmic Nrf2 expression, accompanied by increased expression of HO-1, Gclm, Gclc, and Nqo1 (all P<0.05). Conclusion:Upregulation of S100A9 is involved in the development of HIR-induced acute lung injury, possibly through inhibition of Nrf2 nuclear translocation.

Objective:To investigate the predictive value of elevated calprotectin S100A9 (S100A9) concentration during living-donor liver transplantation (LDLT) for early acute lung injury (ALI) in children with biliary atresia.Method:A retrospective analysis was conducted on 280 pediatric patients with biliary atresia who underwent LDLT using hyperreduced left lateral segment grafts at Tianjin First Central Hospital between January 2019 and January 2021. Based on intraoperative serum S100A9 levels at 30 minutes after graft reperfusion, patients were divided into the high S100A9 group (≥9.05 μg/L, 141 cases) and the low S100A9 group (<9.05 μg/L, 139 cases). General clinical characteristics were compared between the two groups. Univariate and multivariate logistic regression analyses were performed to examine the correlation between S100A9 levels and early postoperative ALI. The predictive value of risk factors was assessed using receiver operating characteristic (ROC) curve analysis with calculation of the area under the curve (AUC) .Result:A total of 280 eligible children were included in the study, with 141 in the high S100A9 group and 139 in the low S100A9 group. The incidence of ALI was significantly higher in the high S100A9 group (31.2%) compared to the low S100A9 group (10.8%). Multivariate regression analysis identified elevated preoperative creatinine levels ( OR=1.191, 95% CI: 1.069~1.321, P=0.002), increased intraoperative S100A9 concentrations ( OR=1.426, 95% CI: 1.272~1.599, P=0.021), and higher intraoperative blood transfusion volume ( OR=0.985, 95% CI: 0.973~0.997, P=0.017) as independent risk factors for postoperative ALI in pediatric LDLT. The predictive value of intraoperative S100A9 levels for ALI was significant, with an AUC of 0.816 (95% CI: 0.758~0.874), a sensitivity of 80.5%, a specificity of 73.7%, and an optimal cutoff value of 9.49 μg/L. Furthermore, preoperative albumin and creatinine levels were found to be correlated with increased intraoperative S100A9 levels. Conclusion:Elevated intraoperative S100A9 levels, increased preoperative creatinine levels, and higher intraoperative blood transfusion volumes are independent risk factors for early ALI following pediatric LDLT. S100A9 levels have strong predictive value for ALI occurrence, highlighting the need for perioperative monitoring and intervention strategies to improve postoperative outcomes.

Modern education emphasizes the improvement of the comprehensive quality of the educated,and medical ed-ucation has particularly high requirements for students'practical abilities.Therefore,it is necessary to continuously analyze and optimize the education work when conditions permit.This paper first introduces the"Trinity Teaching"model and the college student medical technology skills competition.Based on this,it analyzes the advantages and disadvantages of the current training for college student medical technology skills competition,the value of applying the"Trinity Teaching"model,and explores its specific application methods,including the use of group work mode and building a large-scale teaching service system to serve medical teaching work.

Modern education emphasizes the improvement of the comprehensive quality of the educated,and medical ed-ucation has particularly high requirements for students'practical abilities.Therefore,it is necessary to continuously analyze and optimize the education work when conditions permit.This paper first introduces the"Trinity Teaching"model and the college student medical technology skills competition.Based on this,it analyzes the advantages and disadvantages of the current training for college student medical technology skills competition,the value of applying the"Trinity Teaching"model,and explores its specific application methods,including the use of group work mode and building a large-scale teaching service system to serve medical teaching work.

Objective:To investigate the role of calcium-binding protein S100A9 in acute lung injury induced by hepatic ischemia-reperfusion (HIR) in mice, and to explore its relationship with nuclear factor erythroid 2-related factor 2 (Nrf2).Methods:A total of 12 specific pathogen-free (SPF) male wild-type (WT) and 12 S100A9 knockout (S100A9 KO) C57BL/6J mice aged 6~8 weeks and weighing 20-25 g were randomly divided into four groups using a random number table: WT+Sham group, S100A9 KO+Sham group, WT+HIR group, and S100A9 KO+HIR group ( n=6 per group). The HIR model was established by clamping the portal vein and hepatic artery of the left and median liver lobes for 60 minutes followed by reperfusion. At 6 hours post-reperfusion, mice were anesthetized again, and blood samples were collected from the inferior vena cava. Both lungs were harvested. The lung wet-to-dry (W/D) weight ratio was measured. Hematoxylin and eosin (HE) staining was used to assess histopathological changes and calculate lung injury scores. The levels of inflammatory markers—S100A9, tumor necrosis factor-α (TNF-α), and interleukin-6 (IL-6) —as well as oxidative stress indicators including myeloperoxidase (MPO), reactive oxygen species (ROS), malondialdehyde (MDA), and superoxide dismutase (SOD) in serum and lung tissue were measured. Western blotting was used to assess the expression levels of nuclear and cytoplasmic Nrf2, and cytoplasmic HO-1. Results:Compared with the WT+Sham group, both the WT+HIR and S100A9 KO+HIR groups showed significantly increased lung injury scores, W/D ratio, TNF-α, IL-6, ROS, MPO, and MDA levels (all P<0.05). Compared with the WT+HIR group, the S100A9 KO+HIR group exhibited significantly reduced levels of these indicators (all P<0.05). Moreover, the S100A9 KO+HIR group showed elevated nuclear Nrf2 expression and decreased cytoplasmic Nrf2 expression, accompanied by increased expression of HO-1, Gclm, Gclc, and Nqo1 (all P<0.05). Conclusion:Upregulation of S100A9 is involved in the development of HIR-induced acute lung injury, possibly through inhibition of Nrf2 nuclear translocation.

Objective:To investigate the predictive value of elevated calprotectin S100A9 (S100A9) concentration during living-donor liver transplantation (LDLT) for early acute lung injury (ALI) in children with biliary atresia.Method:A retrospective analysis was conducted on 280 pediatric patients with biliary atresia who underwent LDLT using hyperreduced left lateral segment grafts at Tianjin First Central Hospital between January 2019 and January 2021. Based on intraoperative serum S100A9 levels at 30 minutes after graft reperfusion, patients were divided into the high S100A9 group (≥9.05 μg/L, 141 cases) and the low S100A9 group (<9.05 μg/L, 139 cases). General clinical characteristics were compared between the two groups. Univariate and multivariate logistic regression analyses were performed to examine the correlation between S100A9 levels and early postoperative ALI. The predictive value of risk factors was assessed using receiver operating characteristic (ROC) curve analysis with calculation of the area under the curve (AUC) .Result:A total of 280 eligible children were included in the study, with 141 in the high S100A9 group and 139 in the low S100A9 group. The incidence of ALI was significantly higher in the high S100A9 group (31.2%) compared to the low S100A9 group (10.8%). Multivariate regression analysis identified elevated preoperative creatinine levels ( OR=1.191, 95% CI: 1.069~1.321, P=0.002), increased intraoperative S100A9 concentrations ( OR=1.426, 95% CI: 1.272~1.599, P=0.021), and higher intraoperative blood transfusion volume ( OR=0.985, 95% CI: 0.973~0.997, P=0.017) as independent risk factors for postoperative ALI in pediatric LDLT. The predictive value of intraoperative S100A9 levels for ALI was significant, with an AUC of 0.816 (95% CI: 0.758~0.874), a sensitivity of 80.5%, a specificity of 73.7%, and an optimal cutoff value of 9.49 μg/L. Furthermore, preoperative albumin and creatinine levels were found to be correlated with increased intraoperative S100A9 levels. Conclusion:Elevated intraoperative S100A9 levels, increased preoperative creatinine levels, and higher intraoperative blood transfusion volumes are independent risk factors for early ALI following pediatric LDLT. S100A9 levels have strong predictive value for ALI occurrence, highlighting the need for perioperative monitoring and intervention strategies to improve postoperative outcomes.

Objective:To identify the differentially expressed proteins that caused hippocampal damage after liver ischemia-reperfusion (I/R) in rats.Methods:Eighteen clean-grade healthy juvenile male Sprague-Dawley rats, aged 2 weeks, weighing 20-30 g, were divided into 2 groups ( n=9 each) using a random number table method: sham operation group (S group) and liver I/R group (IR group). A rat model of liver I/R injury was prepared by restoring perfusion after 1 h of liver ischemia. The rats were sacrificed after being anesthetized at day 3 of reperfusion, and the hippocampal tissue was isolated and analyzed to obtain gene expression profiles. Differentially expressed genes were identified using the R software, and further protein interaction networks were constructed through Cytoscape and Kyoto Encyclopedia Genes and Genomes pathway analysis to determine the differentially expressed proteins. Quantitative real-time polymerase chain reaction and Western blot were used for validation. Results:A total of 45 differentially expressed proteins were identified by the proteomic analysis of hippocampal tissues, including 36 significantly up-regulated proteins and 9 significantly down-regulated proteins. The proteins with significant expression related to injury were identified from the PPI network complex using the CytoHubBA plug-in cystscape: Ras-related C3 botulinum toxin substrate (RAC2), HRAS, phosphatidylinositol-3-kinase inhibitor phosphatase and tensin homologue (PTEN), and N-methyl-D-aspartate ionotropic glutamate receptor 2b (GRIN2b). The results of quantitative real-time polymerase chain reaction and Western blot showed that the expression of RAC2, HRAS, PTEN, and GRIN2b in the hippocampal tissue was significantly up-regulated in IR group compared with S group ( P<0.05). The results of Kyoto Encyclopedia of Genes and Genomes pathway analysis showed that differentially expressed proteins were significantly enriched in the expression of PD-L1 and its checkpoint pathway, long-term potentiation, and regulation of the Wnt signaling pathway in cancer. Conclusions:The mechanism by which liver I/R induces hippocampal injury may be related to the up-regulation of the expression of RAC2, HRAS, PTEN and GRIN2b in rats.

Objective:To explore the effect of esketamine on inflammatory cytokines and myocardial injury markers in children undergoing living-donor liver transplantation (LT).Methods:Considering the inclusion criteria, 50 children with biliary atresia were selected for living donor LT. They were equally randomized into two groups of control (C) and esketamine (E) (25 cases each). Esketamine 0.5 mg/kg was administered to group E during induction and continued at a dose of 0.5 mg·kg –1·h -1 after an induction of anesthesia. Group C provided the same dose of 0.9% sodium chloride injection during induction and then continued to pumping until the end of the procedure. Basic profiles of two groups were recorded. Hemodynamic parameters, such as heart rate (HR), mean arterial pressure (MAP) and central venous pressure (CVP), were monitored at 5 min of anesthesia induction (T 0), 30 min of anhepatic phase (T 1), immediately after repercussion (T 2), 30 min of neohepatic phase (T 3) and end of surgery (T 4) in both groups. Central venous blood samples were collected at T 0, T 1, T 3 and T 4. Serum levels of cardiac troponin I (cTnI), creatine kinase isoenzyme-MB (CK-MB) ,tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6) were measured. The incidence of adverse cardiac events, postoperative mechanical ventilation time, ICU stay and hospitalization length were compared. Results:As compared with T 0, mean arterial pressure (MAP) at T 2 declined markedly in group E [(48.6±12.7) mmHg (1 mmHg=0.133 kPa) vs (55.6±10.7) mmHg, P<0.001] and C [(39.3±8.0) mmHg vs (53.2±9.4) mmHg, P<0.001 ] ;As compared with T 0, the TNF-α and IL-6 spiked at T 3 in group C [169.0 (207.1) ng/L vs 43.8 (26.4) ng/L, (132.63±51.75) ng/L vs (51.79±17.83) ng/L, P<0.001] and E [78.5 (138.8) ng/L vs 43.8 (26.4) ng/L, (87.44±32.17) ng/L vs (51.79±17.83) ng/L, P<0.001 ] ; In group C, the concentration of myocardial injury markers CK-MB and cTnI rose at T 3/T 4 compared with T 0[T 3 vs T 0: 5.7 (5.4) μg/L vs 4.0 (3.5) μg/L, 0.09 (0.08) μg/L vs 0.02 (0.02) μg/L; T 4 vs T 0: 5.3 (5.0) μg/L vs 4.0 (3.5) μg/L, 0.07 (0.08) μg/L vs 0.02 (0.02) μg/L, P<0.001 ]. In group E, the levels of CK-MB and cTnI were higher at T 3/T 4 than those at T 0[T 3 vs T 0: 7.0 (5.0) μg/L vs 4.6 (2.1) μg/L, 0.06 (0.09) μg/L vs 0.03 (0.04) μg/L; T 4 vs T 0: 5.4 (4.9) μg/L vs 4.6 (2.1) μg/L, 0.03 (0.06) μg/L vs 0.03 (0.04) μg/L; P<0.001]. Compared with group C, the MAP of E rose at T 1/T 2/T 3 [(58.8±10.3) mmHg vs (53.3±8.6) mmHg, P=0.048; (48.6±12.7) mmHg vs (39.3± 8.0) mmHg, P=0.003; (55.8±7.4) mmHg vs (51.5±7.3) mmHg, P=0.044]. Compared with group C, TNF-α and IL-6 decreased in E at T 3/T 4[T 3: 78.5 (138.8) ng/L vs 169.0 (207.1) ng/L, P=0.010; (87.44±32.17) ng/L vs (132.63±51.75) ng/L, P=0.017. T 4: 62.3 (118.3) ng/L vs 141.3 (129.2) ng/L, P=0.001; (74.34±26.38) ng/L vs (100.59±30.40) ng/L, P=0.002]. Compared with group C, cTnI decreased in E at T 3/T 4[0.06 (0.09) μg/L vs 0.09 (0.08) μg/L, P=0.014; 0.03 (0.06) μg/L vs 0.07 (0.08) μg/L, P=0.003]. Compared with group C, the mechanical ventilation time in group E decreased [195 (120) min vs 315 (239) min, P<0.001]. Compared with group C, the incidence of severe hypotension [16%(4/25) vs 48% (12/25), P=0.015 ], bradycardia [12% (3/25) vs 36 % (9/25), P=0.047 ], myocardial ischemia [4 % (1 /25) vs 24 % (6/25), P=0.042 ] and premature ventricular contractions [0 vs 4 %(1/25), P=0.312 ] decreased in group E. Conclusion:Intraoperative dosing of esketamine may suppress inflammatory reactions and alleviate perioperative myocardial injury in children undergoing living-donor LT.

Objective:To evaluate the effect of CD47-overexpressed mesenchymal stem cells (MSCs) on fatty liver ischemia-reperfusion (I/R) injury and the role of signal regulatory protein alpha (SIRPα) in mice.Methods:MSCs from C57 mouse bone marrow were isolated and purified using the density gradient centrifugation, and then CD47 recombinant adenovirus was transfected into MSCs. SPF 4-week-old C57 mice were fed a high-fat diet to induce moderate liver steatosis and then 70% liver I/R model was established. Mice were divided into 4 groups ( n=6 each) using a random number table method: sham operation group (S group), liver I/R group (I/R group), CD47-overexpressed MSCs group (CD47+ I/R group) and CD47-overexpressed MSCs+ SIRPα inhibitor group (CD47+ RRx+ I/R group). MSCs were injected via the tail vein at 24 h before surgery. SIRPα inhibitor RRx-001 1 mg/kg was injected through the tail vein at 48 h before surgery. The mice were anesthetized and sacrificed at 6 h of reperfusion. Blood samples were collected from the inferior vena cava for determination of serum concentrations of alanine transaminase (ALT) and aspartate transaminase (AST). Liver tissues were obtained for examination of the pathological changes and for determiation of the expression of cleaved-caspase 1 (c-caspase-1), gasdermin (GSDM) and PYD domains-containing protein 3 (NLRP3) (by Western blot). Results:Compared with S group, the serum concentrations of ALT and AST were significantly increased, the expression of c-caspase-1, GSDM and NLRP3 in liver tissues was up-regulated ( P<0.05), and the histo-pathological changes of the liver tissue were aggravated in I/R group. Compared with I/R group, the serum concentrations of ALT and AST were significantly decreased, the expression of c-caspase-1, GSDM and NLRP3 in liver tissues was down-regulated ( P<0.05), and the histo-pathological changes of the liver tissue were significantly attenuated in CD47+ I/R group. Compared with CD47+ I/R group, the serum concentrations of ALT and AST were significantly increased, the expression of c-caspase-1, GSDM and NLRP3 in liver tissues was up-regulated ( P<0.05), and the histo-pathological changes of the liver tissue were aggravated in CD47+ RRx+ I/R group. Conclusions:CD47-overexpressed MSCs can alleviate fatty liver I/R injury in mice, and activation of SIRPα and subsequent inhibition of pyroptosis are involved in the process.