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.

ObjectiveTo investigate the effect of SU056， an azo-podophyllotoxin derivative， on carbon tetrachloride （CCl₄）-induced liver fibrosis in mice and related mechanisms of action. MethodsA total of 12 mice were randomly divided into control group， model group （CCl₄+normal saline）， and treatment group （CCl₄+SU056）， with 4 mice in each group. Mice were given intraperitoneal injection of CCl₄ to establish a model of liver fibrosis， and during the middle stage of modeling， the mice in the treatment group were given daily intraperitoneal injection of SU056. Liver histopathological injury， collagen deposition， and liver function were assessed based on HE staining， Masson staining， Sirius Red staining， the content of hydroxyproline in liver tissue， and the serum levels of alanine aminotransferase and aspartate aminotransferase， and immunofluorescence assay was used to measure the expression levels of smooth muscle actin α （α-SMA）， collagen type Ⅰ， and Y-box binding protein 1 （YB1）. The human hepatic stellate cell （HSC） line LX-2 and primary mouse HSC were used， and CCK-8 assay was used to measure cell proliferation； Transwell assay was used to observe cell migration； quantitative reverse transcription-polymerase chain reaction and Western Blot were used to measure the expression levels of collagen type Ⅰ， collagen type Ⅲ， YB1， phosphorylated mammalian target of rapamycin （mTOR）， and phosphorylated S6K， so as to validate the function of the YB1/mTOR signaling axis. The one-way or two-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsIn the mouse model of liver fibrosis induced by CCl₄， compared with the model group， the treatment group had significant alleviation of inflammatory cell infiltration， collagen deposition， and pseudolobule formation in liver tissue and significant reductions in the serum levels of alanine aminotransferase and aspartate aminotransferase and the content of hydroxyproline in liver tissue （all P<0.01）. Immunofluorescence assay showed that SU056 significantly inhibited the abnormal high expression of α-SMA， collagen type I， and YB1 in liver tissue （all P<0.01）. In vitro experiments showed that SU056 inhibited the transforming growth factor-β1-induced proliferation of LX-2 cells （P<0.01）， the migration of LX-2 cells （P<0.05）， and the transcriptional up-regulation of collagen type Ⅰ and collagen type Ⅲ （all P<0.05） in a dose-dependent manner， and SU056 could inhibit the spontaneous activation of primary HSC in vitro. Mechanistic studies revealed that transforming growth factor-β1 simultaneously upregulated the expression levels of YB1， phosphorylated mTOR， and phosphorylated S6K in LX-2 cells， and treatment with SU056 （10 and 20 µmol/L） could downregulate the protein expression levels of collagen type I， YB1， phosphorylated mTOR， and phosphorylated S6K. Specific knockdown of YB1 or administration of the mTOR inhibitor rapamycin exerted a similar effect as SU056. SU056 also inhibited the co-upregulation of α-SMA and phosphorylated mTOR in liver tissue of model mice （P<0.01）. ConclusionSU056 can effectively inhibit HSC activation， proliferation， migration， and extracellular matrix production both in vivo and in vitro and thus delay the progression of liver fibrosis， by disrupting the YB1/mTOR positive feedback signaling axis.

With the accelerating aging of the population, the proportion of elderly patients with lung cancer continues to rise, presenting multiple challenges to perioperative management. This paper systematically reviews the clinical characteristics of elderly lung cancer patients. Based on the comprehensive geriatric assessment, it proposes incorporating seven major geriatric syndromes—frailty, delirium, sarcopenia, cognitive impairment, malnutrition, dysphagia, and mood disorders—into the core evaluation system. By integrating multimorbidity management with complication prevention and control, an integrated "geriatric syndrome-multimorbidity-complication" perioperative management model is constructed. Furthermore, this paper outlines stratified intervention strategies for geriatric syndromes, a "five-step" workflow for comorbidity management, and a comprehensive intervention pathway for complications across the preoperative, intraoperative, and postoperative phases. Multidisciplinary team (MDT) collaboration serves as the core mechanism to achieve individualized comprehensive treatment. This paper aims to provide a novel perioperative comprehensive treatment model for elderly lung cancer patients, which is centered on geriatrics, supported by multidisciplinary collaboration, and guided by precision medicine.

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 explore the role and mechanism of ferroptosis in vitamin D3(VD3)improving the cytotoxicity of keratinocytes(HaCaT cells)induced by nitrogen mustard(NM).Methods HaCaT cells were treated with gradient concentrations of NM(5,10,20,and 50 μmol/L)alone or in combination with ferroptosis inhibitor ferrostatin-1 or liproxstatin-1(10 μmol/L),Nrf2-specific agonist tBHQ(10 μmol/L),and VD3(10 nmol/L),respectively.After co-culture for 24 h,cell viability was assessed,and the intracellular contents of glutathione(GSH)and malondialdehyde(MDA)were measured.Additionally,the expression levels of Nrf2,xCT,and GPX4 were detected.Results NM exerted inhibitory effect on the proliferation of HaCaT cells in a dose-dependent manner,and the cell viability was reduced to approximately 55%at an NM concentration of 20 μmol/L(P<0.05).Ferroptosis inhibitors significantly mitigated the cytotoxic damage induced by NM in HaCaT cells(P<0.05),but activation of nuclear factor E2 related factor 2(Nrf2)markedly attenuated NM-induced ferroptosis,as indicated by the restoration of intracellular GSH level and the decrease in MDA content(P<0.05).VD3 specifically targeted the Nrf2 signaling pathway,upregulated the expression of xCT and GPX4 protein,thereby inhibiting ferroptosis and reducing NM-induced cytotoxicity in HaCaT cells.Conclusion VD3 mitigates NM-induced cytotoxicity in HaCaT cells by inhibiting ferroptosis via Nrf2 activation.

Objective:To construct a risk prediction model for early post-injury respiratory failure in patients with traumatic cervical spinal cord injury (TCSCI) and validate its efficacy.Methods:A retrospective cohort study was conducted to analyze the clinical data of 393 TCSCI patients admitted to Zhengzhou Central Hospital Affiliated to Zhengzhou University from January 2020 to October 2024, including 294 males and 99 females, aged 18-82 years [59(45, 72)years]. Among them, 76 patients had respiratory failure (19.3%). The patients were randomly divided into the training set ( n=275) and validation set ( n=118) at a ratio of 7∶3. According to the presence of respiratory failure within one week after admission, 275 patients in the training set were divided into respiratory failure group ( n=53) and non-respiratory failure group ( n=222). The demographic data, injury characteristics, laboratory test results, and imaging findings of the patients were collected. Risk factors were determined through univariate analysis and multivariate Logistic regression analysis and a nomogram prediction model was constructed. The area under the receiver operating characteristic (ROC) curve (AUC) and Hosmer-Lemeshow test were used to evaluate the discrimination and calibration of the model. Decision curve analysis (DCA) was plotted to evaluate the clinical effectiveness of the prediction model. Results:The results of the univariate analysis showed that there were significant differences in history of respiratory diseases, causes of injury, Glasgow coma scale (GCS), American Spinal Injury Association (ASIA) classification, ASIA-motor score (AMS), injury severity score (ISS), clinical pulmonary infection score (CPIS), hypoproteinemia and cervical vertebra fracture and dislocation between the respiratory failure group and non-respiratory failure group in the training set ( P<0.05). The results of multivariate Logistic regression analysis indicated that GCS, ASIA classification, CPIS, and hypoproteinemia were independent risk factors for early post-injury respiratory failure in TCSCI patients ( P<0.05). Based on the above four variables, a Logistic regression equation was constructed: Logit( P)=2.361-0.675×ASIA classification+0.419×CPIS-0.358×GCS+0.854×hypoproteinemia. In the prediction model established based on this equation, the AUC was 0.96 (95% CI 0.94, 0.99) in the training set and 0.89 (95% CI 0.82, 0.96) in the validation set. In the calibration curves of the training set and validation set, the prediction curve and reference curve were approximately overlapping, with the average absolute errors of 0.04 and 0.03. DCA results demonstrated that both the training and validation sets exhibited positive net benefits when threshold probabilities fell within ranges of 0%-78% and 0%-87%, respectively. Conclusion:The risk prediction model for early post-injury respiratory failure in TCSCI patients based on GCS, ASIA classification, CPIS and hypoproteinemia has good predictive efficacy and clinical practicability.

Objective:To analyze the short-term hospital-based transmission characteristics and gene variation of Carbapenem-Resistant Klebsiella pneumoniae (CRKP) by genome-wide technique to provide evidence for transmission control. Methods:The experimental strain was derived from all the CRKP isolated in Affiliated Hospital of North China University of Science and Technology from October 2022 to December 2023. Strain identification and drug susceptibility were tested with VITEK 2-Compact automatic bacterial identification drug susceptibility analyzer or disk method, and the results were interpreted through whole genome sequencing. The ST type, carbapenem resistance gene, virulence factor, and O serotype of the collected strains were analyzed.Results:Among the 115 strains of CRKP, 94 strains were isolated from the intensive care unit (ICU), accounting for 81.7%, and 21 strains were isolated from the non-intensive care unit (NICU), accounting for 18.3%. The 115 strains of CRKP can be divided into 11 ST types, of which ST11 type was the most (54.8%, 63/115), followed by ST15 type (22.6%, 26/115) and ST5492 type (15.7%, 18/115). Type ST5492 was a new clonal group in the region. The 115 strains of CRKP could be divided into 7 O serotypes, most of which were O2a type(32.2%,37/115), followed by O5 type(30.4%,35/115) and O1 type(27.8%,32/115). The resistance genes of carbapenem antibiotics showed that there were 107 strains carrying the blaKPC-2 gene, one strain with the blaNDM-1 gene, and one strain with both the blaKPC-2 and blaNDM-13 genes. Virulence genes were detected in 55 CRKP strains (47.8%, 55/115), among which six strains detected peg-344, iucA, iroB, rmpA, and rmpA2 virulence genes (5.2%, 6/115). Four virulence genes ( peg-344, iucA, rmpA, and rmpA2) were detected in 34 strains (29.6%, 34/115). Three virulence genes ( iucA, iroB and rmpA) were detected in two strains (1.7%, 2/115). Three virulence genes ( peg-344, iucA and rmpA) were detected in one strain (0.8%, 1/115). IucA and rmpA virulence genes were detected in 12 strains (10.4%, 12/115). KPC-2_ST11_O2a, KPC-2_ST15_O1 and KPC-2_ST5492_O5 were dominant clones, and their distribution was mainly in the intensive care unit. The whole genome sequence analysis showed that there were three dominant clones, among which ST11 clones were subdivided into three dominant O serotypes, all of which were mainly in the intensive care unit. Conclusion:The popular strain in the hospital of CRKP is a KPC-2_ST11 clone group carrying iucA, rmpA/rmpA2, with cross-department transmission and mutation. ST5492 is a newly-launched clone type. The intensive care unit of hvKP carrying five virulence genes, including peg-344, should be alert to the epidemic risk of CR-hvKP outbreak.

Objective:To analyze the carriage status, subtype distribution and flanking gene sequence characteristics of oxacillinases (OXA enzyme) in 241 clinical strains of Pseudomonas aeruginosa, and assess their roles in the drug resistance of Pseudomonas aeruginosa and ability to horizontally transfer across species. Methods:Clinical P. aeruginosa isolates were collected from four hospitals in Sanya, Tangshan, Zhangjiakou, and Beijing. The prevalence of oxacillinases and their flanking gene sequences was analyzed by whole-genome sequencing (NGS) and bioinformatic approaches. Results:A total of 241 isolates of P. aeruginosa were gathered, and 35 blaOXA subtypes were identified through screening of 252 blaOXA genes. These genes were classified into three subfamilies: blaOXA-50-like (241, 95.6%), blaOXA-1-like (9, 3.6%) and blaOXA-10-like (2, 0.8%). Among these, 11 subtypes (11, 31.4%) were novel blaOXA subtypes. Nine of these belonged to the blaOXA-50-like subfamily and were designated as blaOXA-1244, blaOXA-1245, blaOXA-1246, blaOXA-1250, blaOXA-1252, blaOXA-1253, blaOXA-1254, blaOXA-1255, and blaOXA-1256. The remaining two belonged to the blaOXA-10-like subfamily and were named blaOXA-1247 and blaOXA-1248. Compared to the amino acid sequence of OXA-10, the newly identified subtype OXA-1247 exhibited a mutation at position 117, where a valine was replaced by a leucine. This change was thought to improve the enzyme′s ability to hydrolyze carbapenems. In the analysis of the flanking sequences of the blaOXA genes, Class I integrons were identified in four bacterial strains. The variable regions of these integrons carried three distinct patterns of resistance gene cassettes: aac( 6′) -Ib-blaOXA-1247-ant( 3′′) -Ia, aac( 6′) -Ib-blaOXA-1248 and aac( 6′) -Ib- blaIMP-45-blaOXA-1-catB3. Among these, the strain BJ2326 carried a class I integron that was connected to the downstream IS CR1 element to form a composite class I integron structure, additionally carrying the resistance gene blaPER-1. Out of the 223 non-wild-type P. aeruginosa strains, 127 strains exhibited non-wild-type profiles to the four beta-lactam antibiotics MEM, CAZ, FEP, and TZP, with the combination of MEM+CAZ+FEP being the most prevalent, representing 57.0% of the total. Conclusions:The blaOXA genes in 241 clinical P. aeruginosa strains showed diversity. Some blaOXA genes had a co-transfer risk with the metallo-β-lactamase resistance gene blaIMP-45. Among the 11 newly discovered blaOXA subtypes, the new subtype OXA-1247 may have carbapenemase activity and potential for horizontal transfer.

To analyze the prevalence, drug resistance and whole genome characteristics of Mycoplasma pneumoniae (MP) in respiratory throat swab samples of hospitalized children with pneumonia in Suzhou City from 2023 to 2024. Throat swab samples of hospitalized children aged 0-14 years old with pneumonia in Suzhou were collected from September 2023 to September 2024. Real-time fluorenscence quantitative PCR technology was used to detect MP nucleic acid. The results showed that the positive rate of MP in 3 235 samples was 22.44% (726/3 235), with a rate of 55.00% in week 47 of 2023. The positive rate of MP increased with age ( χ2=45.842, P<0.001). The study selected MP nucleic acid test positive samples from week 20 (5.13-5.19) to week 23 (6.3-6.9) of 2024 for isolation, culture and resistance phenotype detection. About 31 MP strains were successfully isolated and cultured, all of which were resistant to macrolides. The next-generation sequencing technology and nanopore sequencing technology were used for genome sequencing. All 31 strains carried the A2063G mutation, with the main prevalent genotype being the P1-1, and the main mlST type being the ST3. Despite the overall genomic similarity between strains being over 99%, there were significant differences between the P1-1 and P1-2 strains in the P1 gene region. In summary, from 2023 to 2024, the main MP type prevalent in Suzhou City is the P1-1 genotype. All isolated MP strains carry an A2063G resistance site mutation and are resistant to macrolides, requiring continuous monitoring and further research.

Objective:To explore the evaluation method for key performance indicators of autonomous ultrasound scanning robots,so as to establish a testing scheme and conduct experiments.Methods:Based on the working principle of autonomous ultrasound scanning robots,three key performance indicators,which included scanning speed,scanning contact force,and accuracy of online adjustment,were established.The speed of the robotic arm,which execute autonomous scanning,was tested through laser rangefinders and a design of process equipment for displacement.The contact force of autonomous scanning was monitored and evaluated using a combination of ultrasound phantom and sensor with six-dimensional force.The displacement differences of phantom and robotic arm were monitored to evaluate the accuracy of online adjustment through designed a synchronization detection device for the displacements of phantom and robotic arm.Results:This research designed and provided test method and test device,which realized successful measurements for the speed,contact force,and accuracy of online adjustment in autonomous scanning of the ultrasonic scanning robot.Conclusion:The speed,contact force,and accuracy of online adjustment in scanning can be used as evaluation indicators of systematic performance of autonomous ultrasound scanning robots.The feasibility of these indicators is demonstrated through designed evaluation methods and corresponding experiments.