Objective To compare the performance and efficacy of prognostic models constructed by different machine learning algorithms in predicting the survival period of lung transplantation (LTx) recipients. Methods Data from 483 recipients who underwent LTx were retrospectively collected. All recipients were divided into a training set and a validation set at a ratio of 7:3. The 24 collected variables were screened based on variable importance (VIMP). Prognostic models were constructed using random survival forest (RSF) and extreme gradient boosting tree (XGBoost). The performance of the models was evaluated using the integrated area under the curve (iAUC) and time-dependent area under the curve (tAUC). Results There were no significant statistical differences in the variables between the training set and the validation set. The top 15 variables ranked by VIMP were used for modeling and the length of stay in the intensive care unit (ICU) was determined as the most important factor. Compared with the XGBoost model, the RSF model demonstrated better performance in predicting the survival period of recipients (iAUC 0.773 vs. 0.723). The RSF model also showed better performance in predicting the 6-month survival period (tAUC _{6 months} 0.884 vs. 0.809, P = 0.009) and 1-year survival period (tAUC _{1 year} 0.896 vs. 0.825, P = 0.013) of recipients. Based on the prediction cut-off values of the two algorithms, LTx recipients were divided into high-risk and low-risk groups. The survival analysis results of both models showed that the survival rate of recipients in the high-risk group was significantly lower than that in the low-risk group (P<0.001). Conclusions Compared with XGBoost, the machine learning prognostic model developed based on the RSF algorithm may preferably predict the survival period of LTx recipients.

Exosomes represent a class of nanoscale extracellular vesicles that facilitate the exchange of genetic information among various cells.Alzheimer's disease(AD)stands as a progressive neurodegenerative disorder characterized by its subtle and advan-cing onset,representing the foremost form of dementia lacking effective therapeutic interventions.Notably,investigations have illuminated the involvement of exosomes in the pathogenesis of AD,attributing diagnostic and therapeutic significance to their role,particularly concerning exosomal microRNAs(miRNA).The miRNAs carried by exosomes serve as potential biomarkers for AD,while also exhibiting potential benefits in ameliorating cognitive dysfunction in individuals afflicted by AD.This article aims to comprehensively review the origins of exosomes(encom-passing both mesenchymal cell-derived exosomes and brain-de-rived exosomes)and their potential as therapeutic agents targe-ting AD.

Objective To analyze the risk factors of gastrointestinal bleeding in patients with type A aortic dissection(TAAD)after Sun's operation.Methods The clinical data of 87 patients who underwent TAAD Sun's operation in our hospital from March 2021 to June 2022 were retrospectively analyzed.They were divided into the bleeding group and the non-bleeding group according to whether there was gastrointestinal bleeding after operation.The clinical data of patients in the two groups was compared and analyzed.The binary Logistic regression analysis was used to analyze the risk factors of gastrointestinal bleeding.The clinical predictor of postoperative gastrointestinal bleeding was analyzed by receiver operating characteristic(ROC)curve.Results In this study,there were 40 cases of postoperative gastrointestinal bleeding(the bleeding group)and 47 cases of non-bleeding(the non-bleeding group).Compared with the non-bleeding group,the bleeding group had a shorter onset time,a higher proportion of patients with hypertension history,a higher preoperative creatinine abnormality rate,more intraoperative blood loss,longer postoperative mechanical ventilation time,higher postoperative infection rate,and higher poor prognosis rate,with statistically significant differences(P<0.05).There was no statistically significant difference in the gender,age,gastrointestinal diseases history,smoking history,preoperative platelets,preoperative international normalized ratio(INR),preoperative alanine aminotransferase(ALT),preoperative aspartate aminotransferase(AST),preoperative γ-glutamyl transpeptidase(GGT),preoperative dissection involving abdominal aorta,operation time,intraoperative cardiopulmonary bypass time,intraoperative circulatory arrest time,intraoperative aortic occlusion time or intraoperative blood transfusion rate.Logistic regression analysis showed that hypertension history(OR=2.468,95%CI:0.862 to 7.067,P=0.037),preoperative creatinine>105 μmol/L(OR=3.970,95%CI:1.352 to 11.659,P=0.011),long postoperative mechanical ventilation time(OR=1.015,95%CI:0.094 to 1.018,P=0.041)and postoperative infection(OR=3.435,95%CI:0.991 to 11.900,P=0.012)were the independent risk factors for postoperative gastrointestinal bleeding in TAAD patients.ROC curve showed that the postoperative mechanical ventilation time exceeding 64 hours were the clinical predictor of postoperative gastrointestinal bleeding in TAAD patients.Conclusion The prognosis of TAAD patients with postoperative gastrointestinal bleeding after Sun's operation is poor.Hypertension history,preoperative acute renal insufficiency,long postoperative mechanical ventilation time and postoperative infection are closely related to postoperative gastrointestinal bleeding in TAAD patients after operation,which should be paid more attention to,and corresponding evaluation,early identification and early intervention should be made to improve the prognosis of patients.

Objective:To investigate the effects of Xiongcan Yishen Formula(XYF)on ferroptosis in mouse TM3 Leydig cells after oxidative stress injury(OSI)induced by H2O2.Methods:An oxidative stress injury model was established in mouse TM3 Leydig cells using H2O2 induction.The modeled TM3 cells were randomly divided into OSI group,XYF group,the ferroptosis inhibitor Ferrostatin-1(F-1)group,and F-1+XYF group,which were respectively intervened with blank serum,20%drug-containing serum,2μmol/L F-1,and2μmol/L F-1+20%drug-containing serum.A control group(normal TM3 cells+blank serum)was also set up.The morphology of cells in each group was observed,and the levels of testosterone,superoxide dismutase(SOD),reactive oxygen spe-cies(ROS),malondialdehyde(MDA),ferritin heavy chain 1(FTH1),solute carrier family 7 member 11(SLC7A11),glutathione(GSH),glutathione peroxidase 4(GPX4),fatty acid CoA ligase 4(FACL4),total iron ions,and ferrous ions were detected.Re-sults:Compared with the model group,the control group showed significantly decreased expression of ROS,MDA,FACL4,total iron,and ferrous ions(P<0.05),and significantly increased levels of testosterone,SOD,GSH,FTH1,SLC7A11,and GPX4(P<0.05).The male silkworm kidney-tonifying formula group significantly promoted testosterone secretion by TM3 cells and upregulated the expression of FTH1,SLC7A11,GPX4,GSH,and SOD in TM3 cells(P<0.05),while significantly downregulating ROS,MDA,FACL4,total iron ions,and ferrous ions(P<0.05).Conclusion:Following H2O2 exposure,oxidative stress can induce ferroptosis in mouse TM3 Leydig cells.XYF can antagonize OSI and ferroptosis in TM3 cells by activating the SLC7A11/GSH/GPX4 axis,which may underlie the mechanism of XYF in the treatment of male late-onset hypogonadism.

Objective:To determine the differential expressions of long non-coding RNA(lncRNA)and messenger RNA(mRNA)in normal and asthenospermia(AS)men and analyze their biological significance in AS.Methods:We isolated and ex-tracted total RNAs from 9 normal and 9 AS sperm samples,determined the expressions of RNAs in the sperm using the DNBSEQ se-quencing platform,and analyzed their relevant functions by gene ontology enrichment(GO)and Kyoto encyclopedia of genes and ge-nomes pathway(KEGG)analyses.Results:An average of 10.64G data was generated per group,with 282 185 RNAs detected,in-cluding 107 009 lncRNAs.Among the total number of lncRNAs,15 157 were differentially expressed,2 190 upregulated and 12 967 downregulated;and among the 19 514 mRNAs,13 736 were differentially expressed,4 995 upregulated and 8 741 downregulated.Differentially expressed genes were enriched mainly in the sperm cell membrane and the pathways related to the ion channel functions,sperm development and fertilization.Conclusion:Differentially expressed lncRNAs and mRNAs can be identified by sequencing a-nalysis of AS and normal sperm.Regulation of sperm function through membrane ion channels may contribute to the development of AS,which provides a molecular basis for further research on AS.

Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

Objective:To explore the patterns of failure after postoperative intensity-modulated radiotherapy for gastric cancer.Methods:Clinical data of patients diagnosed with gastric cancer or gastroesophageal junction carcinoma with pathological stages T 3-4N 0 or T xN 1-3 admitted to Cancer Hospital of Chinese Academy of Medical Sciences from May 2009 to December 2018 were retrospectively analyzed. All patients received postoperative radiotherapy. During the follow-up, tumor recurrence was confirmed by imaging or endoscopic or pathological data, etc. According to the location of tumor recurrence, recurrence patterns were divided into local, regional and distant recurrence. Differences in recurrence patterns among different groups were compared using t-test and Chi-square test. Patient survival was assessed through Kaplan-Meier method. Results:A total of 76 patients were enrolled, with a median age of 49 years old (27-67 years old), 34 cases (45%) were classified as T 3 stage, 40 cases (53%) of T 4 stage, and 75 cases (99%) of N 1-3 stage, respectively. Seventy-three patients (92%) were classified as stage Ⅲ, and 38 patients (50%) underwent D2 dissection. The median follow-up time was 32.8 months (7.1-138.5 months). The median time of recurrence was 17.6 months (2.9-113.6 months). The median survival time after recurrence was 8.19 months (0.6-91.9 months). There were 13 cases (17%) of local recurrence, 6 cases (8%) of regional recurrence, and 72 cases (95%) of distant metastasis in patients. Peritoneal metastasis (33 cases, 43%) and distant lymph node metastasis (12 cases, 16%) were the main patterns of distant recurrence. Conclusions:By intensity-modulated radiotherapy technology, adjuvant radiotherapy yields favorable local and regional control for gastric cancer. Distant metastasis is still the main pattern of recurrence.

Objective:To analyze clinical efficacy of intensity-modulated chemoradiotherapy for patients with anal squamous cell carcinoma and identify prognostic factors.Methods:Clinical data of patients with anal squamous cell carcinoma who received intensity-modulated chemoradiotherapy in the Cancer Hospital of Chinese Academy of Medical Sciences from January 1, 2010 to January 1, 2022 were retrospectively analyzed. Regular follow-up was carried out. The main indexes included disease-free survival (DFS), locoregional failure-free survival (LRFFS) and overall survival (OS), and adverse reactions were recorded. The survival curve was delineated by Kaplan-Meier method and the influencing factors of survival were analyzed by Cox regression models.Results:A total of 65 patients were enrolled with 19 (29%) males and 46 (71%) females. According to the American Joint Committee on Cancer (AJCC) 7 th edition staging, there were 7 (11%), 28 (43%), 10 (15%), and 20 (31%) patients with stage I, II, IIIa, and IIIb, respectively. Before the chemoradiotherapy, 2 (3%) patients received chemotherapy and 12 (18%) patients received local resection. The median dose of radiotherapy was 54 Gy (range: 45-64 Gy) and the main concurrent chemotherapy regimen was capecitabine combined with cisplatin ( n=34, 52%). The completion rate of radiotherapy during concurrent chemoradiotherapy was 100%, and the chemotherapy completion rate was 88%. During the therapy, 5 patients (8%) were interrupted but completed concurrent chemoradiotherapy in full dose, and 8 patients (12%) reduced the dose of concurrent chemotherapy due to the toxicities. During the chemoradiotherapy, 15 cases (23%) experienced grade 3-4 leukopenia, and 17 cases (26%) experienced grade 3-4 radiation dermatitis. No treatment-related death occurred during the treatment. The median follow-up time was 50.4 months (range: 4.4-142.2 months), local recurrence occurred in 7 cases (11%), distant metastasis occurred in 3 cases (5%), and the 5-year DFS, LRFFS and OS rates were 78.8%, 86.5% and 85.1%, respectively. Cox univariate analysis indicated that T stage was significantly associated with DFS ( P=0.006), and tended to be associated with OS ( P=0.054). Conclusions:Intensity-modulated radiotherapy combined with concurrent chemotherapy is an effective treatment for anal squamous cell carcinoma, with tolerable acute toxicities. T stage is an influencing factor of DFS in anal squamous cell carcinoma patients.

With the optimization of surgical technologies and postoperative management regimens, the number of lung transplantation has been significantly increased, which has become an important treatment for patients with end-stage lung disease. However, due to the impact of comprehensive factors, such as bronchial ischemia and immunosuppression, the incidence of airway stenosis after lung transplantation is relatively high, which severely affects postoperative survival and quality of life of lung transplant recipients. In recent years, with the improvement of perioperative management, organ preservation and surgical technologies, the incidence of airway stenosis after lung transplantation has been declined, but it remains at a high level. Early diagnosis and timely intervention play a significant role in enhancing clinical prognosis of patients with airway stenosis. In this article, the general conditions, diagnosis, treatment and prevention of airway stenosis after lung transplantation were reviewed, aiming to provide reference for comprehensive management of airway stenosis after lung transplantation and improving clinical prognosis of lung transplant recipients.