Objective: To assess the clinical application value of a prediction model for red blood cell (RBC) demand in surgical procedures. Methods: Demographic data, laboratory parameters, anesthesia and transfusion records, and model prediction data were retrospectively collected from surgical patients at the First Medical Center of Chinese PLA General Hospital between 2018 and 2024. Statistical analysis was performed using the Chi-square test, t-test, and Mann-Kendall trend test. Results: From 2018 to 2024, the predictive model for RBC demand in surgical procedures was used to evaluate a total of 112 293 surgeries. During this period, the model call rate (77.49%-98.91%, P<0.05), compliance rate (56.81%-84.92%, P<0.05), and prediction accuracy rate (66.82%-94.17%, P<0.05) all showed significant upward trends. The total blood usage across the hospital (13645.4-7723.5 units, P<0.05) and the average blood usage per surgery (0.21-0.1 units, P<0.05) exhibited overall downward trends. Postoperative average hemoglobin levels in the non-compliance group (112.1-105.3 g/L in the non-compliance group vs 106.9-92.7 g/L in the compliance group, P<0.05) and the intraoperative excessive transfusion rate (5.06%-6.05% in the non-compliance group vs 0.09%-0.04% in the compliance group, P<0.05) were significantly higher in the non-compliance group compared to the compliance group. Conclusion: The predictive model for RBC demand in surgical procedures has played a positive role in conserving blood resources, optimizing blood resource allocation, and reducing intraoperative risks.

Objective To investigate the radon activity concentrations in subways of Nanning City and assess the average annual effective doses for subway staff and passengers due to radon exposure. Methods Sixty-three stations across the subway lines 2, 3, and 5 were selected as study sites. Radon activity concentrations were measured using the scintillation counting method with scintillation vials. Results The radon activity concentrations in subway lines 2, 3, and 5 were 7.9-24.4, 12.0-26.2, and 12.6-18.2 Bq/m³, respectively. The average radon activity concentrations for these three lines were (17.4 ± 4.6), (19.1 ± 4.1), and (14.6 ± 1.7) Bq/m³, respectively. Statistical analysis using SPSS 26.0 software revealed a significant difference in radon activity concentrations among these stations (P<0.01). Considering the data in previous research, the average radon activity concentration across all stations in the subway lines of Nanning City was determined to be 17.4 Bq/m³. The estimated average annual effective dose due to radon exposure was 0.131 mSv for subway staff and 0.033 mSv for passengers. Conclusion The radon activity concentrations in the subway lines of Nanning City were significantly lower than the national standard limit (400 Bq/m³). The annual effective doses from radon exposure for both subway staff and passengers were below the limits specified in the Basic Standards for Protection Against Ionizing Radiation and for the Safety of Radiation Sources (GB18871—2002). The health impact of radon and its progeny on subway staff and passengers in the subway lines of Nanning City was extremely low and can be considered negligible.

Background Work-related musculoskeletal disorders (WMSDs) are a major occupational health concern, particularly among workers exposed to adverse ergonomic conditions. Manganese production involves heavy physical demands, yet research on WMSDs among manganese workers remains limited. Objective To investigate the prevalence and influencing factors of WMSDs among manganese workers in a manganese enterprise in Guangxi. Methods A cross-sectional survey was conducted from May to June 2024 on workers at a manganese factory in Guangxi. The Chinese Musculoskeletal Disorders Questionnaire was used to collect information on demographic characteristics, distribution of musculoskeletal symptoms, and work-related exposures. χ² test was applied to compare differences in positive WMSDs rates across groups, and logistic regression analysis was performed to identify associated factors. Results A total of 1476 workers were enrolled in the study after pre-determined inclusion and exclusion criteria. The overall prevalence of WMSDs was 34.15%. The most commonly affected body regions were the lower back (17.28%), neck (16.67%), and shoulders (13.82%). The results of logistic regression analysis indicated that female, older age, and education level of college or above were associated with a higher risk of WMSDs (P<0.05). Awkward working postures were significantly associated with WMSDs in corresponding body regions; in particular, awkward postures of the neck, upper limbs, trunk, and lower limbs were related to an increased risk of WMSDs in multiple body sites (P<0.05). In addition, poor lighting conditions, high workplace temperature, frequent or sustained arm support during work, and high job demands were associated with an increased risk of overall or site-specific WMSDs (P<0.05). Conclusion The high prevalence of WMSDs among manganese workers is closely associated with demographic characteristics, working postures, and work environment and organizational factors. Targeted ergonomic interventions focusing on high-risk body regions and key ergonomic exposures are warranted to reduce the risk of WMSDs among manganese workers.

Objective To explore the correlations of the severity degrees of coronary stenosis with cardiac function and exercise tolerance. Methods A total of 112 patients who underwent coronary angiography in Cardiology Department of Zhongshan Hospital, Fudan University between October 2024 and January 2025 were enrolled. According to the imaging results, the Gensini score was calculated, and the patients were divided into three groups based on the scores: mild group (＜20 points, n＝42), moderate group (20-40 points, n＝43), and severe group (＞40 points, n＝27). The left ventricular ejection fraction (LVEF), N-terminal pro-brain natriuretic peptide (NT-proBNP) level and its abnormal elevation ratio, 6-minute walk distance (6MWD), and grip strength were compared among the groups. The correlations between Gensini score and various indicators were analyzed using multivariate linear regression. And the multivariate binary logistic regression analysis was used to analyze the related factors of severe coronary stenosis. Results The 6MWD and LVEF values in the severe group were lower than those in the mild and moderate groups (P＜0.01), while the NT-proBNP level and its abnormal elevation ratio in the severe group were higher than those in the mild group (P＜0.05). The Gensini score was negatively correlated with 6MWD (β＝−0.965, P＜0.01), and positively correlated with NT-proBNP level and its abnormal elevation ratio (β＝0.015, P＜0.001; β＝0.003, P＝0.037). 6MWD and diabetes were independent related factors of severe coronary stenosis (OR＝0.956, P＜0.001; OR＝5.701, P＝0.038). Conclusions The cardiac function and exercise tolerance in patients with severe coronary stenosis decrease, 6MWD is helpful of recognizing severe coronary stenosis population.

OBJECTIVE To investigate the improving effect and mechanism of Wenyang huayu formula on cerebral ischemia-reperfusion injury in rats based on nuclear factor-erythroid 2-related factor 2 （Nrf2）/glutathione peroxidase 4 （GPX4） signaling pathway and mitochondrial ferroptosis pathway. METHODS SD rats were randomly divided into sham operation group， model group，Nimodipine tablet group （10.8 mg/kg ）， and Wenyang huayu formula group （28 g/kg）， with 24 rats in each group. Except for the sham operation group， rats in other groups were all subjected to middle cerebral artery occlusion model by Longa thread occlusion method. After successful modeling， rats in each administration group were intragastrically gavaged with corresponding liquid for 7 days or 14 days， while rats in sham operation group and model group were given equal volume of normal saline once a day. At 7 and 14 days after administration， neurological deficit scores of rats were calculated； the ultrastructure of neuronal mitochondria in ischemic brain tissue of rats was observed；the contents of malondialdehyde （MDA）， glutathione （GSH） and Fe 2+ ， as well as the protein and mRNA expression levels of Nrf2， solute carrier family 7 member 11 （SLC7A11） and GPX4 in ischemic brain tissue of rats were detected. RESULTS At 7 and 14 days after administration， compared with the sham operation group， the neuronal mitochondria in ischemic brain tissue of rats in the model group showed typical changes of ferroptosis， and the injury continued to worsen over time； the neurological deficit scores， the contents of MDA and Fe 2+ were significantly increased （ P ＜0.05），while the content of GSH and the protein and mRNA expression levels of Nrf2， SLC7A11 and GPX4 were significantly decreased （ P ＜0.05）. Compared with the model group， the morphology of neuronal mitochondria in ischemic brain tissue of rats in Nimodipine tablet group and Wenyang huayu formula group was gradually improved over time， and the above quantitative indicators were significantly reversed （ P ＜0.05）；moreover， the improvement effect of most indicators in Wenyang huayu formula group was significantly better than that in Nimodipine tablet group （ P ＜0.05）. CONCLUSIONS Wenyang huayu formula can improve cerebral ischemia-reperfusion injury in rats， and its mechanism may be related to activating Nrf2/GPX4 signaling pathway and inhibiting mitochondrial ferroptosis.

Objective To investigate the clinical prognostic value of the prognostic nutritional index (PNI) in patients with renal cell carcinoma (RCC) undergoing partial nephrectomy.Methods A retrospective analysis was conducted on the clinical data of RCC patients who underwent partial nephrectomy at our hospital during 2020 and 2024.The optimal cutoff value of PNI was determined based on the maximum Youden index from the receiver operating characteristic (ROC) curve.The clinicopathological characteristics, overall survival (OS), and progression-free survival (PFS) between patients with different PNI levels were compared.Cox regression analysis was used to explore the independent prognostic factors for RCC patients. Results Based on the ROC curve, the optimal cutoff value corresponding to the maximum Youden index was calculated to be 46.675, at which point the sensitivity was 65.3% and the specificity was 62.2%.Of the 815 patients included in the study, 293 (36.0%) patients had a PNI＜46.675.Cox regression analysis confirmed that preoperative PNI, tumor diameter, ISUP classification, and ECOG score were independent risk factors for postoperative OS in patients with RCC who underwent PN (P＜0.05).In addition, preoperative PNI, tumor diameter, ISUP classification and ECOG score were independent risk factors for postoperative PFS (P＜0.05).After covariates in the multivariable Cox regression model were adjusted, patients in the low PNI group demonstrated significantly shorter overall survival (HR=2.392, P＜0.001) and significantly poorer progression-free survival (HR=2.076, P＜0.001) compared to those in the high PNI group.Conclusion Preoperative PNI has significant clinical value in evaluating the prognosis of RCC patients undergoing partial nephrectomy.An elevated preoperative PNI is associated with a better prognosis.

Objective To investigate the efficacy of discontinuous density gradient combined with swim-up method for bacterial removal in frozen semen,and to provide experimental evidence for the safe application of frozen semen in assisted reproductive technology.Methods A total of 208 frozen semen samples containing non-pathogenic bacteria,cryopreserved in our human sperm bank from January 2019 to December 2023,were selected.The thawed semen samples were processed using discontinuous density gradient combined with swim-up method.To simulate in vitro fertilization procedures,the processed sperm suspensions were subjected to 5-day in vitro culture for bacterial residue monitoring.Prior to cryopreservation,all semen samples underwent routine bacterial culture to exclude pathogenic microorganisms.Post-thaw semen samples,processed sperm suspensions,and 5-day culture media were sent to an independent third-party laboratory for comprehensive bacterial identification.Results Among the 208 frozen semen samples containing non-pathogenic bacteria,41 bacterial species were identified,with 1～4 species per sample.After processing with discontinuous density gradient combined with swim-up method,the sterility rate of the sperm suspension reached 89.42%(186/208),with residual bacteria including Enterococcus faecalis,Corynebacterium glucuronolyticum,Group B Streptococcus,and Corynebacterium glycinophilum.After 5-day in vitro culture,the sterility rate increased to 93.75%(195/208),with residual bacteria limited to Entero-coccus faecalis and Group B Streptococcus.Conclusions The combined method of discontinuous density gradient and swim-up technique effectively eliminates most bacteria in frozen semen.However,the clearance rate for Entero-coccus faecalis and Group B Streptococcus remains below 90%.Optimization of pre-freezing bacterial screening and post-thaw processing techniques is necessary to enhance the safety of frozen semen in assisted reproductive technology.

BACKGROUND:Cervical instability is a common orthopedic disease in young and middle-aged people,and is the early manifestation of cervical spondylosis,which has a great impact on the quality of life of patients.Therefore,early diagnosis of cervical instability to implement early intervention has positive clinical and social significance.OBJECTIVE:The clinical prediction model of cervical instability in young and middle-aged people was constructed based on machine learning to realize early screening of cervical instability in young and middle-aged people before X-ray examination.METHODS:From September 2022 to October 2023,155 young and middle-aged adults with cervical instability and 88 with non-cervical instability recruited through recruitment advertisements and spinal department outpatient of Wangjing Hospital,China Academy of Chinese Medical Sciences were selected as research subjects.The research subjects'general information,living and working habits,discomfort symptoms,visual analog scale score,Neck Disability Index,and 36-ltem Short Form Health Survey were collected on site based on questionnaires.The above information was used as predictive factors.After screening,six machine learning algorithms of Support Vector Machine,LightGBM,RandomForest,Logistic,AdaBoost,and XGBClassifier were used to train the model by ten-fold cross-validation method,and the clinical prediction model of cervical instability was constructed.Area under the curve was used as the main evaluation index.Univariate analysis was performed on the predictors,and SHAP method was used to rank the importance of the predictors.Correlation heat maps were used to show the degree of linear correlation between the predictors and the cervical instability.RESULTS AND CONCLUSION:(1)Among the six machine learning models,RandomForest model was chosen as the final prediction model,including nine predictors,such as age,body mass index,neck circumference/neck length,visual analog scale score,Neck Disability Index,bodily pain,general health,vitality,and mental health,area under the curve=0.725 4,and the calibration degree was good.It could be used as a reference tool for early screening of cervical instability in young and middle-aged people.(2)There were significant differences in age,visual analog scale score,Neck Disability Index,bodily pain,general health,and vitality between the two groups(P＜0.05).(3)The order of importance of predictors was age,Neck Disability Index,visual analog scale score,general health,body mass index,vitality,bodily pain,neck circumference/neck length,mental health,among which age,visual analog scale score,Neck Disability Index were positively correlated with cervical instability,while general health,body mass index,vitality,bodily pain,neck circumference/neck length,and mental health were negatively correlated with cervical instability.

Objective To investigate the efficacy of discontinuous density gradient combined with swim-up method for bacterial removal in frozen semen,and to provide experimental evidence for the safe application of frozen semen in assisted reproductive technology.Methods A total of 208 frozen semen samples containing non-pathogenic bacteria,cryopreserved in our human sperm bank from January 2019 to December 2023,were selected.The thawed semen samples were processed using discontinuous density gradient combined with swim-up method.To simulate in vitro fertilization procedures,the processed sperm suspensions were subjected to 5-day in vitro culture for bacterial residue monitoring.Prior to cryopreservation,all semen samples underwent routine bacterial culture to exclude pathogenic microorganisms.Post-thaw semen samples,processed sperm suspensions,and 5-day culture media were sent to an independent third-party laboratory for comprehensive bacterial identification.Results Among the 208 frozen semen samples containing non-pathogenic bacteria,41 bacterial species were identified,with 1～4 species per sample.After processing with discontinuous density gradient combined with swim-up method,the sterility rate of the sperm suspension reached 89.42%(186/208),with residual bacteria including Enterococcus faecalis,Corynebacterium glucuronolyticum,Group B Streptococcus,and Corynebacterium glycinophilum.After 5-day in vitro culture,the sterility rate increased to 93.75%(195/208),with residual bacteria limited to Entero-coccus faecalis and Group B Streptococcus.Conclusions The combined method of discontinuous density gradient and swim-up technique effectively eliminates most bacteria in frozen semen.However,the clearance rate for Entero-coccus faecalis and Group B Streptococcus remains below 90%.Optimization of pre-freezing bacterial screening and post-thaw processing techniques is necessary to enhance the safety of frozen semen in assisted reproductive technology.

Objective To analyze the risk factors of delayed wound recovery after Meek skin grafting in patients with extensive deep burn and its predictive efficiency.Methods A total of 100 patients with extensive deep burn who underwent Meek skin grafting from August 2018 to November 2024 were selected,and they were divided into the normal group(n=79)and the delayed group(n=21)according to the wound healing time.The clinical data of all patients were collected,and the influencing factors of delayed wound recovery after Meek skin grafting in patients with extensive deep burn were analyzed by Logistic regression model,and the efficiency of the model was analyzed by the receiver operating characteristic(ROC)curve and the Hosmer-Lemeshow goodness-of-fit test,respectively.Results There were statistically significant differences in the body mass index,hospitalization time,burn index,burn area,donor skin area,number of postoperative dressing change,postoperative nutritional support,postoperative pain scores,and hospitalized blood glucose levels between the two groups(P<0.05).Logistic regression analysis showed that high burn index(OR=1.086,β=0.082),large burn area(OR=1.155,β=0.144),fewer postoperative dressing change(OR=0.746,β=-0.293),lack of postoperative nutritional support(OR=6.439,β=1.862),high postoperative pain score(OR=4.483,β=1.500),and high level of hospitalized blood glucose(OR=2.251,β=0.811)were the influencing factors for delayed wound recovery after Meek skin grafting in patients with extensive deep burn(P<0.05).The ROC curve revealed that the combined prediction of the above six influencing factors for delayed postoperative wound recovery had an area under the ROC curve(AUC)of 0.896,with a sensitivity and specificity of 88.00%and 89.10%,respectively;and the Hosmer-Lemeshow test result showed:χ2=10.641,and P=0.223,indicating a high predictive efficacy and a certain calibration ability of the model.Conclusion The high burn index,large burn area,fewer postoperative dressing change,lack of postoperative nutritional support,high postoperative pain score and hospitalized blood glucose level were the influencing factors for delayed wound recovery after Meek skin grafting in patients with extensive deep burn,and the prediction model constructed by the above factors has good predictive ability,which can provide a reference for clinical treatment.