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

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:Synchronous mucinous metaplasia and neoplasia of the female genital tract (SMMN-FGT) occurring at multiple sites during the same period of time is extremely rare, and the aim of this study was to investigate the clinicopathologic features of SMMN-FGT and its relationship with prognosis.Methods:We retrospectively analyzed the clinicopathological features and follow-up records of 25 cases of SMMN-FGT diagnosed from January 2012 to October 2022 in the case database of Obstetrics and Gynecology Hospital of Fudan University.Results:The median age at onset was 46 years old, respectively. Clinical manifestations included irregular vaginal bleeding or drainage, pelvic pain, and ovarian cysts, etc. Germline genetic test confirmed Peutz-Jeghers syndrome (P-J syndrome) in two patients. All patients underwent surgery, and 13 patients had postoperative adjuvant radiotherapy and/or chemotherapy. The most frequent site of lesion was the cervix (21 cases), with 11, 10 and 16 cases occurring in the endometrium, fallopian tubes and ovaries, respectively. Six cases involved three sites simultaneously, and only one case had all four sites involved at the same time. Among the 9 cases with P53 mutation phenotype, 6 cases had gastric-type mucinous adenocarcinoma, 2 cases had lobular endocervical glandular hyperplasia, and 1 case had mucinous adenocarcinoma, whereas all the minimally deviated adenocarcinomas had wild phenotype of P53. The median follow-up time was 59 months, during which 3 cases died and 6 cases developed local recurrence or distant metastasis. According to our analysis, postoperative recurrence or metastasis was correlated with the FIGO stage of the disease, the number of lesion sites and the severe degree of the uterine lesions ( P＜0.05). Conclusions:SMMN-FGT has a relatively good clinical prognosis, and even advanced patients can benefit from surgery and adjuvant therapy. In young patients, the ovaries may be preserved if no evidence of lesions are seen after adequate evaluation. In SMMN-FGT, gastric-type mucinous adenocarcinoma occurring in the cervix may have a better prognosis than gastric-type mucinous adenocarcinoma of the cervix alone, so the accurate diagnosis of SMMN-FGT is critical for clinical management.

Background::Homoharringtonine (HHT) is an effective anti-inflammatory, anti-viral, and anti-tumor protein synthesis inhibitor that has been applied clinically. Here, we explored the therapeutic effects of HHT in a mouse heart transplant model.Methods::Healthy C57BL/6 mice were used to observe the toxicity of HHT in the liver, kidney, and hematology. A mouse heart transplantation model was constructed, and the potential mechanism of HHT prolonging allograft survival was evaluated using Kaplan–Meier analysis, immunostaining, and bulk RNA sequencing analysis. The HHT-T cell crosstalk was modeled ex vivo to further verify the molecular mechanism of HHT-induced regulatory T cells (Tregs) differentiation. Results::HHT inhibited the activation and proliferation of T cells and promoted their apoptosis ex vivo. Treatment of 0.5 mg/kg HHT for 10 days significantly prolonged the mean graft survival time of the allografts from 7 days to 48 days ( P <0.001) without non-immune toxicity. The allografts had long-term survival after continuous HHT treatment for 28 days. HHT significantly reduced lymphocyte infiltration in the graft, and interferon-γ-secreting CD4 + and CD8 + T cells in the spleen ( P <0.01). HHT significantly increased the number of peripheral Tregs (about 20%, P <0.001) and serum interleukin (IL)-10 levels. HHT downregulated the expression of T cell receptor (TCR) signaling pathway-related genes ( CD4, H2-Eb1, TRAT1, and CD74) and upregulated the expression of IL-10 and transforming growth factor (TGF) -β pathway-related genes and Treg signature genes ( CTLA4, Foxp3, CD74, and ICOS). HHT increased CD4 + Foxp3 + cells and Foxp3 expression ex vivo, and it enhanced the inhibitory function of inducible Tregs. Conclusions::HHT promotes Treg cell differentiation and enhances Treg suppressive function by attenuating the TCR signaling pathway and upregulating the expression of Treg signature genes and IL-10 levels, thereby promoting mouse heart allograft acceptance. These findings may have therapeutic implications for organ transplant recipients, particularly those with viral infections and malignancies, which require a more suitable anti-rejection medication.

Objective:Synchronous mucinous metaplasia and neoplasia of the female genital tract (SMMN-FGT) occurring at multiple sites during the same period of time is extremely rare, and the aim of this study was to investigate the clinicopathologic features of SMMN-FGT and its relationship with prognosis.Methods:We retrospectively analyzed the clinicopathological features and follow-up records of 25 cases of SMMN-FGT diagnosed from January 2012 to October 2022 in the case database of Obstetrics and Gynecology Hospital of Fudan University.Results:The median age at onset was 46 years old, respectively. Clinical manifestations included irregular vaginal bleeding or drainage, pelvic pain, and ovarian cysts, etc. Germline genetic test confirmed Peutz-Jeghers syndrome (P-J syndrome) in two patients. All patients underwent surgery, and 13 patients had postoperative adjuvant radiotherapy and/or chemotherapy. The most frequent site of lesion was the cervix (21 cases), with 11, 10 and 16 cases occurring in the endometrium, fallopian tubes and ovaries, respectively. Six cases involved three sites simultaneously, and only one case had all four sites involved at the same time. Among the 9 cases with P53 mutation phenotype, 6 cases had gastric-type mucinous adenocarcinoma, 2 cases had lobular endocervical glandular hyperplasia, and 1 case had mucinous adenocarcinoma, whereas all the minimally deviated adenocarcinomas had wild phenotype of P53. The median follow-up time was 59 months, during which 3 cases died and 6 cases developed local recurrence or distant metastasis. According to our analysis, postoperative recurrence or metastasis was correlated with the FIGO stage of the disease, the number of lesion sites and the severe degree of the uterine lesions ( P＜0.05). Conclusions:SMMN-FGT has a relatively good clinical prognosis, and even advanced patients can benefit from surgery and adjuvant therapy. In young patients, the ovaries may be preserved if no evidence of lesions are seen after adequate evaluation. In SMMN-FGT, gastric-type mucinous adenocarcinoma occurring in the cervix may have a better prognosis than gastric-type mucinous adenocarcinoma of the cervix alone, so the accurate diagnosis of SMMN-FGT is critical for clinical management.

Objective:The mouse kidney transplantation model presents challenges in terms of surgical difficulty and low success rate,making it difficult to master.This study aims to provide a crucial model for transplantation immunology research by modifying and developing novel techniques for mouse kidney transplantation. Methods:A total of 57 pairs of mice were used to establish and compare the modified and innovative surgical techniques for mouse kidney transplantation.Three different surgical models were established,including the abdominal suture technique for orthotopic kidney transplantation,the abdominal cuff technique for orthotopic kidney transplantation,and the cervical cuff technique for ectopic kidney transplantation.BALB/c or C57BL/6 male mice,aged 8 to 12 weeks and weighed 20 to 25 g with specified pathogen free-grade were served as the donor mice or the recipient mice.The surgical technique characteristics,key surgical times,complications,and pathological examination in the early postoperative period were summarized and compared. Results:Three different surgical models of mouse kidney transplantation were successfully established.The comparison of warm ischemic time for the 3 groups of mice showed no statistical significance(P=0.510 4).The abdominal suture group had the shortest total operation time of the donor compared with the abdominal cuff group and the cervical cuff group[(18.3±3.6)min vs(26.2±4.7)min and(22.8±2.5)min;both P<0.000 1].There was a significant difference in cold ischemia time among the 3 groups(all P<0.000 1),with(60.8±4.1)min in the cervical cuff group,(43.3±5.0)min in the abdominal suture group,and(88.8±6.7)min in the abdominal cuff group.Due to different anastomosis methods,the cervical cuff group had the shortest time[(17.6±2.7)min],whereas the abdominal cuff group had the longest time[(38.8±5.4)min].The total operation time for the recipients showed significant differences(P<0.000 1),with the abdominal suture group having the shortest time[(44.0±6.9)min],followed by the cervical cuff group[(64.1±5.2)min],and the abdominal cuff group[(80.0±6.0)min]being the longest.In the 32 mice of the abdominal suture group,there were 6 with intraoperative bleeding,including 1 arterial intimal injury bleeding and 5 with bleeding after vessel opening.Six mice had ureteral complications,including ureteral bladder anastomotic stenosis,necrosis,and renal pelvis dilation.Two mice had postoperative abdominal infections.In the abdominal cuff group,there was no intraoperative bleeding,but 6 mice showed mild arterial stenosis and 5 showed venous stenosis,4 arterial injury,4 arterial thrombosis,and 2 ureteral complications.No postoperative infections occurred in the mice.In the cervical cuff group,no intraoperative bleeding,arterial intimal injury,arterial/venous stenosis,or thrombosis were found in 13 mice.Five mice had ureteral complications,including ureteral necrosis and infection,which were the main complications in the cervical cuff group.The renal function in mice of the 3 groups remained stable 7 days after surgery.Hematoxylin and eosin staining and periodic acid-Schiff staining showed no significant differences in terms of acute rejection among the 3 surgical methods(all P>0.05). Conclusion:All 3 surgical methods are able to successfully establish mouse kidney transplantation models,with no significant differences observed in the short-term graft survival and acute rejection.The modified abdominal suture technique and abdominal cuff technique have their respective advantages in research applications.The novel cervical cuff technique for ectopic kidney transplantation model is relatively simple to be prepared and causes less trauma to the mice,providing more options for studies involving xenotransplantation,secondary transplantation,and local lymphatic drainage.However,the difficulty in harvesting the donor kidney and the high incidence of ureteral infections need further validation in long-term survival.This study holds important reference value for choosing the type of mouse kidney transplantation model for different research needs.

Objective:To summarize the clinical, pathological and molecular characteristics of various types of pediatric glioma, and to explore the differences in the morphology and clinical significance among various types of pediatric glioma.Methods:Based on the fifth edition of the World Health Organization classification of central nervous system tumors, this study classified or reclassified 111 pediatric gliomas that were diagnosed at Guangzhou Medical University Affiliated Women and Children′s Medical Center from January 2020 to June 2023. The clinical manifestations, imaging findings, histopathology, and molecular characteristics of these tumors were analyzed. Relevant literature was also reviewed.Results:The 111 patients with pediatric glioma included 56 males and 55 females, with the age ranging from 10 days to 13 years (average age, 5.5 years). Clinically, manifestations presented from 5 days to 8 years before the diagnosis, including epilepsy in 16 cases, increased intracranial pressure in 48 cases and neurological impairment in 66 cases. MRI examinations revealed tumor locations as supratentorial in 43 cases, infratentorial in 65 cases, and spinal cord in 3 cases. There were 73 cases presented with a solid mass and 38 cases with cystic-solid lesions. The largest tumor diameter ranged from 1.4 to 10.6 cm. Among the 111 pediatric gliomas, there were 6 cases of pediatric diffuse low-grade glioma (pDLGG), 63 cases of circumscribed astrocytoma glioma (CAG), and 42 cases of pediatric diffuse high-grade glioma (pDHGG). Patients with pDLGG and CAG were younger than those with pDHGG. The incidence of pDLGG and CAG was significantly lower in the midline of the infratentorial region compared to that of pDHGG. They were more likely to be completely resected surgically. The pDLGG and CAG group included 4 cases of pleomorphic xanthoastrocytoma, showing histological features of high-grade gliomas. Among the high-grade gliomas, 13 cases were diffuse midline gliomas and also showed histological features of low-grade glioma. Immunohistochemical studies of H3K27M, H3K27ME3, p53, ATRX, BRAF V600E, and Ki-67 showed significant differences between the pDLGG and CAG group versus the pDHGG group ( P<0.01). Molecular testing revealed that common molecular variations in the pDLGG and CAG group were KIAA1549-BRAF fusion and BRAF V600E mutation, while the pDHGG group frequently exhibited mutations in HIST1H3B and H3F3A genes, 1q amplification, and TP53 gene mutations. With integrated molecular testing, 2 pathological diagnoses were revised, and the pathological subtypes of 35.3% (12/34) of the pediatric gliomas that could not be reliably classified by histology were successfully classified. Conclusions:There are significant differences in clinical manifestations, pathological characteristics, molecular variations, and prognosis between the pDLGG, CAG and pDHGG groups. The integrated diagnosis combining histology and molecular features is of great importance for the accurate diagnosis and treatment of pediatric gliomas.

Objective To establish a county-level trauma treatment model,designed to prioritize efficiency and guided by a multidisciplinary approach for emergency green channels.Methods Adhering to the Consensus of Experts on the Construc-tion and Management of Trauma Centers in Municipal Comprehensive Hospitals(2020),and using the trauma center creation plan from Guangdong Province as a reference,we established a county-level trauma center,leveraging its strengths and unique at-tributes,with the emergency department as its core.Results The application of information technology facilitated the establish-ment of a two-way referral information platform and a three-tiered diagnosis and treatment system for county medical communities,thereby enhancing the efficiency and quality of healthcare.The implementation of the emergency green channel multidisciplinary treatment team model significantly improved the admission rates for complex and critical cases and increased the utilization of new technologies.Conclusion The development of a county-level emergency treatment system,spearheaded by the establishment of a provincial-level trauma center and a multidisciplinary team model for emergency green channels,can expedite trauma patient care,augment diagnostic efficiency and treatment efficacy,and catalyze advancements in medical technology within county hospitals.