Objective To evaluate the predictive value of different machine learning models constructed in a multicenter environment for potential organ donors and verify their clinical application feasibility. Methods The study included 2 000 inpatients admitted to five domestic tertiary hospitals from January 2020 to December 2023, who met the criteria for potential organ donation assessment. They were randomly divided into a training set and an internal validation set (7∶3). Another 300 similar patients admitted to the First Affiliated Hospital of Harbin Medical University from January 2024 to April 2025 were included as an external validation set. The area under the curve (AUC), sensitivity, specificity, accuracy and F1-score of three models were compared, and the consistency of the potential organ donor determination process was tested. Multivariate logistic regression analysis was used to identify predictive factors of potential organ donors. Decision curve analysis (DCA) was employed to verify the resource efficiency of each model, and the threshold interval and intervention balance point were assessed. Results Apart from age, there were no significant differences in other basic characteristics among the centers (all P>0.05). The consistency of the potential organ donor determination process among researchers in each center was good [all 95% confidence interval (CI) lower limits >0]. In the internal validation set, the XGBoost model had the best predictive performance (AUC=0.92, 95% CI 0.89-0.94) and the best calibration (P=0.441, Brier score 0.099). In the external validation set, the XGBoost model also had the best predictive performance (AUC=0.91, 95% CI 0.88-0.94), outperforming logistic regression and random forest models. Multivariate logistic regression showed that mechanical ventilation had the greatest impact (odds ratio=2.06, 95% CI 1.54-2.76, P<0.001). DCA indicated that the XGBoost model had the highest net benefit in the threshold interval of 0.2-0.6. The “treat all” strategy only had a slight advantage at extremely low thresholds. The recommended threshold interval, which balances intervention costs and clinical benefits, considers ≥50% positive predictive value (PPV) and ≤50 referrals per 100 high-risk patients. Conclusions The XGBoost model established in a multicenter environment is accurate and well-calibrated in predicting potential organ donors. Combined with DCA, it may effectively guide the timing of clinical interventions and resource allocation, providing new ideas for the assessment and management of organ donation after brain death.

Esculetin, a natural dihydroxy coumarin derived from the Chinese herbal medicine Cortex Fraxini, has demonstrated significant pharmacological activities, including anticancer properties. Ferroptosis, an iron-dependent form of regulated cell death, has garnered considerable attention due to its lethal effect on tumor cells. However, the exact role of ferroptosis in esculetin-mediated anti-hepatocellular carcinoma (HCC) effects remains poorly understood. This study investigated the impact of esculetin on HCC cells both in vitro and in vivo. The findings indicate that esculetin effectively inhibited the growth of HCC cells. Importantly, esculetin promoted the accumulation of intracellular Fe²⁺, leading to an increase in ROS production through the Fenton reaction. This event subsequently induced lipid peroxidation (LPO) and triggered ferroptosis within the HCC cells. The occurrence of ferroptosis was confirmed by the elevation of malondialdehyde (MDA) levels, the depletion of glutathione peroxidase (GSH-Px) activity, and the disruption of mitochondrial morphology. Notably, the inhibitor of ferroptosis, ferrostatin-1 (Fer-1), attenuated the anti-tumor effect of esculetin in HCC cells. Furthermore, the findings revealed that esculetin inhibited the Nrf2-xCT/GPx4 axis signaling in HCC cells. Overexpression of Nrf2 upregulated the expression of downstream SLC7A11 and GPX4, consequently alleviating esculetin-induced ferroptosis. In conclusion, this study suggests that esculetin exerts an anti-HCC effect by inhibiting the activity of the Nrf2-xCT/GPx4 axis, thereby triggering ferroptosis in HCC cells. These findings may contribute to the potential clinical use of esculetin as a candidate for HCC treatment.
Umbelliferones/administration & dosage* ; Ferroptosis/drug effects* ; Carcinoma, Hepatocellular/physiopathology* ; NF-E2-Related Factor 2/genetics* ; Humans ; Liver Neoplasms/physiopathology* ; Phospholipid Hydroperoxide Glutathione Peroxidase/genetics* ; Animals ; Cell Line, Tumor ; Mice ; Amino Acid Transport System y+/genetics* ; Mice, Inbred BALB C ; Male ; Signal Transduction/drug effects* ; Lipid Peroxidation/drug effects* ; Reactive Oxygen Species/metabolism* ; Mice, Nude

General practice standardized residency training is a crucial part of postgraduate education for cultivating general practitioner. The factors influencing the quality of general practice residency training cover various aspects such as the residents themselves, teaching staff, management and decision-making levels, as well as teaching resources. Guided by the goal of "fostering virtue through education", and integrated the spirit of Norman Bethune and modern innovation theories and the educational philosophy, the China-Japan Union Hospital of Jilin University has carried out comprehensive reforms in this field. It has constructed a PDCA cycle management system based on the concept of total quality management to improve the quality of education from multiple links such as quality planning and process monitoring. In terms of faculty development, based on the dissipative structure theory, a mechanism of "selection, evaluation, incentive, and elimination" has been established. Teacher communities have been formed and a training college has been established to strengthen the teaching team. In terms of platform construction, the linkage between "teaching base-community" and "on campus-off campus" has been strengthened and resources have been integrated. The reform has achieved remarkable results, and our practice may provide a reference for general practice medical education.

S-methyl-L-cysteine sulfoxide (SMCO) is a non-protein sulfur-containing amino acid with a variety of functions. There are few reports on the enzymes catalyzing the biosynthesis of SMCO from S-methyl-L-cysteine (SMC). In this study, the flavin-containing monooxygenase gene derived from Schizosaccharomyces pombe (spfmo) was heterologously expressed in Escherichia coli BL21(DE3) and the enzymatic properties of the expressed protein were analyzed. The optimum catalytic conditions of the recombinant SpFMO were 30 ℃ and pH 8.0, under which the enzyme activity reached 72.77 U/g. An appropriate amount of Mg²⁺ improved the enzyme activity. The enzyme kinetic analysis showed that the K_m and k_cat/K_m of SpFMO on the substrate SMC were 23.89 μmol/L and 61.71 L/(min·mmol), respectively. Under the optimal reaction conditions, the yield of SMCO synthesized from SMC catalyzed by SpFMO was 12.31% within 9 h. This study provides reference for the enzymatic synthesis of SMCO.
Schizosaccharomyces/genetics* ; Escherichia coli/metabolism* ; Recombinant Proteins/metabolism* ; Cysteine/biosynthesis* ; Mixed Function Oxygenases/metabolism* ; Schizosaccharomyces pombe Proteins/metabolism* ; Oxygenases/metabolism* ; Kinetics

Objective To develop an erythrocyte-based delivery system for butyrylcholinesterase(BChE)that is capable of prophylaxis against organophosphorus nerve agents.Methods Recombinant BChE was produced and analyzed for oligomerization via polyacrylamide gel electrophoresis(PAGE)and Western blotting.A modified hypotonic preswelling method was employed to prepare BChE-loaded erythrocytes.The drug loading capacity and encapsulation efficiency were quantified using enzyme-linked immunosorbent assay(ELISA).Catalytic activity was assessed in vitro with an activity detection kit.The system was characterized via scanning electron microscopy(SEM),flow cytometry and a hematology analyzer.Results Recombinant BChE predominantly existed as dimers(85％dimer,15％monomer).The optimized volume ratio of erythrocytes to hypotonic solution was determined as 1:7.Compared with native and empty erythrocytes,BChE-loaded erythrocytes exhibited significantly higher catalytic activity(P＜0.001).The mean corpuscular volume of BChE-loaded erythrocytes increased(P＜0.001),while the mean content of corpuscular hemoglobin and hemoglobin in erythrocytes per 100 mL decreased(P＜0.001).SEM revealed no morphological differences(biconcave disc shape).Hypotonic preswelling moderately increased erythrocyte apoptosis(P＜0.001),but no statistical difference was observed between BChE-loaded and hypotonic-treated erythrocytes(P＞0.05).CD47 expression remained unchanged compared to native erythrocytes(P＞0.05).Conclusion The modified hypotonic preswelling method can generate BChE-loaded erythrocytes that retain the characteristics of native erythrocytes while conferring catalytic activity,offering a novel strategy for clinical intervention against organophosphorus poisoning.

Objective:To investigate the correlation between transabdominal bowel ultrasongraphy (TBUS) parameters and disease activity of ulcerative colitis (UC).Methods:The results of TBUS, endoscopy and laboratory tests of 68 UC patients (108 examinations) who visited the Department of Gastroenterology of the Second Hospital (Eastern Campus) of Hebei Medical University From January 2022 to February 2024 were retrospectively analyzed. According to Mayo endoscopic score (MES), there were 10 cases of remission (MES=0) and 98 cases of active phase (MES>0); patients in active phase further classified into 16 cases of mild (MES=1), 19 cases of moderate (MES=2), and 63 cases of severe (MES=3). The TAUS parameters were compared between patients in remission and active phases. Spearman rank correlation analysis was used to analyze the correlation between the TBUS parameters including bowel wall thickness (BWT), Limberg score, wall layer stratification, fat wrapping and endoscopic activity score, laboratory inflammatory indicators. Receiver operating characteristic curve (ROC) analysis was applied to evaluate the predictive efficacy of the TBUS parameters and laboratory inflammatory indicators in identifying remission under endoscopy. Independent sample t-test and Fisher′s exact probability method were used to compare the two groups. Results:The BWT of patients in remission was significantly thinner than that of patients in active phase ((2.99±0.41) mm vs. (5.66±1.57) mm, t=-5.34, P<0.001). The proportions of patients in remisson with Limberg score ≤2, normal wall layer stratification, and absence of fat wrapping were significantly higher than those of patients in active phase (10/10 vs. 34/98, 10/10 vs. 48/98, 10/10 vs. 41/98, Fisher′s exact test, P<0.001, =0.002, =0.001). BWT, Limberg score, wall layer stratification, and fat wrapping were positively correlated with MES ( r=0.676, 0.677, 0.441, and 0.493, all P<0.001). BWT and Limberg score were moderate positively correlated with C-hypersensitive reactive protein, erythrocyte sedimentation rate and fecal calprotectin (BWT: r=0.561, 0.420 and 0.458, all P<0.001; Limberg score: r=0.576, 0.469 and 0.403, all P<0.001), and were negatively correlated with serum albumin and hemoglobin (BWT: r=-0.604 and -0.453, both P<0.001; Limberg score: r=-0.573 and -0.532, both P<0.001). The results of ROC analysis showed that BWT achieved the best predictive efficacy in identifying endoscopic remission, and the best cut-off value was 3.45 mm (area under the curve was 0.972, 95% confidence interval: 0.944 to 1.000, P<0.001), with a sensitivity of 93.9% and specificity of 100.0%. Conclusions:TBUS parameters can accurately reflect disease activity in UC. It is a powerful tool for UC monitoring. The BWT<3.45 mm is the best cut-off value in prediction of endoscopic remission.

Objective:To investigate the short-term efficacy of bevacizumab combined with chemotherapy in patients with advanced cervical cancer, as well as its effects on tumor markers and immune function.Methods:A retrospective analysis was conducted on 60 patients with advanced cervical cancer who received treatment at Yiwu Central Hospital from January 2020 to March 2024. The patients were divided into an observation group and a control group ( n = 30 per group) based on whether they received bevacizumab. Patients in the observation group received bevacizumab in combination with chemotherapy, while those in the control group received chemotherapy alone. The two groups were evaluated over two consecutive treatment cycles, with each cycle lasting 21 days. Short-term efficacy was compared between the two groups. The Karnofsky score, tumor markers, and immune function were assessed before and after treatment in both groups. Additionally, the incidence of adverse reactions was compared between the two groups. Results:The objective response rate in the observation group was significantly higher than that in the control group [73.33% (22/30) vs. 46.67% (14/30), χ2 = 4.44, P<0.05]. After treatment, the Karnofsky score in the observation group was significantly higher than that in the control group [(83.39 ± 4.43) vs. (75.48 ± 4.06), t = 7.21, P<0.001]. The serum levels of carbohydrate antigen 125, carcinoembryonic antigen, and carbohydrate antigen 19-9 in the observation group were all significantly lower than those in the control group ( t = -11.27, -8.91, -13.33, all P<0.001). CD 3+, CD 4+, and CD 4+/CD 8+ were significantly higher in the observation group compared with the control group ( t = 10.20, 10.74, 10.17, all P<0.001). The incidence of adverse reactions did not differ significantly between the two groups (all P>0.05). Conclusions:In patients with advanced cervical cancer, bevacizumab combined with chemotherapy demonstrates better efficacy than chemotherapy alone. The combined therapy is more effective in lowering serum levels of carbohydrate antigen 125, carcinoembryonic antigen, and carbohydrate antigen 19-9, as well as enhancing immune function, without increasing adverse reactions compared with chemotherapy alone.

Objective:To investigate the short-term efficacy of bevacizumab combined with chemotherapy in patients with advanced cervical cancer, as well as its effects on tumor markers and immune function.Methods:A retrospective analysis was conducted on 60 patients with advanced cervical cancer who received treatment at Yiwu Central Hospital from January 2020 to March 2024. The patients were divided into an observation group and a control group ( n = 30 per group) based on whether they received bevacizumab. Patients in the observation group received bevacizumab in combination with chemotherapy, while those in the control group received chemotherapy alone. The two groups were evaluated over two consecutive treatment cycles, with each cycle lasting 21 days. Short-term efficacy was compared between the two groups. The Karnofsky score, tumor markers, and immune function were assessed before and after treatment in both groups. Additionally, the incidence of adverse reactions was compared between the two groups. Results:The objective response rate in the observation group was significantly higher than that in the control group [73.33% (22/30) vs. 46.67% (14/30), χ2 = 4.44, P<0.05]. After treatment, the Karnofsky score in the observation group was significantly higher than that in the control group [(83.39 ± 4.43) vs. (75.48 ± 4.06), t = 7.21, P<0.001]. The serum levels of carbohydrate antigen 125, carcinoembryonic antigen, and carbohydrate antigen 19-9 in the observation group were all significantly lower than those in the control group ( t = -11.27, -8.91, -13.33, all P<0.001). CD 3+, CD 4+, and CD 4+/CD 8+ were significantly higher in the observation group compared with the control group ( t = 10.20, 10.74, 10.17, all P<0.001). The incidence of adverse reactions did not differ significantly between the two groups (all P>0.05). Conclusions:In patients with advanced cervical cancer, bevacizumab combined with chemotherapy demonstrates better efficacy than chemotherapy alone. The combined therapy is more effective in lowering serum levels of carbohydrate antigen 125, carcinoembryonic antigen, and carbohydrate antigen 19-9, as well as enhancing immune function, without increasing adverse reactions compared with chemotherapy alone.

General practice standardized residency training is a crucial part of postgraduate education for cultivating general practitioner. The factors influencing the quality of general practice residency training cover various aspects such as the residents themselves, teaching staff, management and decision-making levels, as well as teaching resources. Guided by the goal of "fostering virtue through education", and integrated the spirit of Norman Bethune and modern innovation theories and the educational philosophy, the China-Japan Union Hospital of Jilin University has carried out comprehensive reforms in this field. It has constructed a PDCA cycle management system based on the concept of total quality management to improve the quality of education from multiple links such as quality planning and process monitoring. In terms of faculty development, based on the dissipative structure theory, a mechanism of "selection, evaluation, incentive, and elimination" has been established. Teacher communities have been formed and a training college has been established to strengthen the teaching team. In terms of platform construction, the linkage between "teaching base-community" and "on campus-off campus" has been strengthened and resources have been integrated. The reform has achieved remarkable results, and our practice may provide a reference for general practice medical education.

Objective:To investigate the correlation between transabdominal bowel ultrasongraphy (TBUS) parameters and disease activity of ulcerative colitis (UC).Methods:The results of TBUS, endoscopy and laboratory tests of 68 UC patients (108 examinations) who visited the Department of Gastroenterology of the Second Hospital (Eastern Campus) of Hebei Medical University From January 2022 to February 2024 were retrospectively analyzed. According to Mayo endoscopic score (MES), there were 10 cases of remission (MES=0) and 98 cases of active phase (MES>0); patients in active phase further classified into 16 cases of mild (MES=1), 19 cases of moderate (MES=2), and 63 cases of severe (MES=3). The TAUS parameters were compared between patients in remission and active phases. Spearman rank correlation analysis was used to analyze the correlation between the TBUS parameters including bowel wall thickness (BWT), Limberg score, wall layer stratification, fat wrapping and endoscopic activity score, laboratory inflammatory indicators. Receiver operating characteristic curve (ROC) analysis was applied to evaluate the predictive efficacy of the TBUS parameters and laboratory inflammatory indicators in identifying remission under endoscopy. Independent sample t-test and Fisher′s exact probability method were used to compare the two groups. Results:The BWT of patients in remission was significantly thinner than that of patients in active phase ((2.99±0.41) mm vs. (5.66±1.57) mm, t=-5.34, P<0.001). The proportions of patients in remisson with Limberg score ≤2, normal wall layer stratification, and absence of fat wrapping were significantly higher than those of patients in active phase (10/10 vs. 34/98, 10/10 vs. 48/98, 10/10 vs. 41/98, Fisher′s exact test, P<0.001, =0.002, =0.001). BWT, Limberg score, wall layer stratification, and fat wrapping were positively correlated with MES ( r=0.676, 0.677, 0.441, and 0.493, all P<0.001). BWT and Limberg score were moderate positively correlated with C-hypersensitive reactive protein, erythrocyte sedimentation rate and fecal calprotectin (BWT: r=0.561, 0.420 and 0.458, all P<0.001; Limberg score: r=0.576, 0.469 and 0.403, all P<0.001), and were negatively correlated with serum albumin and hemoglobin (BWT: r=-0.604 and -0.453, both P<0.001; Limberg score: r=-0.573 and -0.532, both P<0.001). The results of ROC analysis showed that BWT achieved the best predictive efficacy in identifying endoscopic remission, and the best cut-off value was 3.45 mm (area under the curve was 0.972, 95% confidence interval: 0.944 to 1.000, P<0.001), with a sensitivity of 93.9% and specificity of 100.0%. Conclusions:TBUS parameters can accurately reflect disease activity in UC. It is a powerful tool for UC monitoring. The BWT<3.45 mm is the best cut-off value in prediction of endoscopic remission.