BACKGROUND:The most common complication of traumatic femoral neck fractures after internal fixation is femoral head necrosis.Currently,many studies have reported on the risk factors that affect the occurrence and development of postoperative femoral head necrosis,but there is still a lack of tools to predict the risk of femoral head necrosis after internal fixation of femoral neck fractures.OBJECTIVE:To develop a predictive model that estimates the risk of femoral head necrosis shortly after patients with femoral neck fractures receive cannulated screw internal fixation.METHODS:A retrospective analysis reviewed clinical records of 172 patients who underwent cannulated screw internal fixation for femoral neck fractures at Department of Orthopedics of Mianyang Central Hospital from January 2013 to June 2023.Patients were categorized into two groups based on the presence or absence of femoral head necrosis within one year post-operation:the necrosis group and the non-necrosis group.Univariate analysis,Lasso regression,and multivariate Logistic regression techniques were employed to identify the determinants of femoral head necrosis.A nomogram prediction model was constructed using R language's"rms"package,version 4.0.The receiver operating characteristic curve was used to evaluate the discriminatory ability of the model.The Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model,and the decision curve analysis was used to determine its clinical application benefits.Internal validation of the study was conducted using the Bootstrap method,involving 1 000 repeated samplings.To delve deeper into the primary factors influencing femoral head necrosis post-internal fixation of the femoral neck,this paper employed the SHAP method for data set analysis.RESULTS AND CONCLUSION:(1)The risk factors leading to femoral head necrosis in the short term after cannulated screw fixation of femoral neck fractures include:smoking,diabetes,Garden classification,fracture line location,reduction quality,age,and operation time.(2)The prediction model demonstrated robust performance,evidenced by an area under the curve of 0.940(95％Confidence Interval:0.903 to 0.977),indicating a high level of prediction accuracy.The model achieved a sensitivity of 90.2％and a specificity of 87.6％,indicating that its diagnostic performance was stable.The Hosmer-Lemeshow goodness-of-fit test yielded a chi-square value of 6.593 with a P-value of 0.581,confirming that the model's predictions closely align with the observed outcomes.(3)The calibration curve of the model also performed well,and its overall trend was very close to the ideal curve,further proving the high accuracy of the model.(4)The internal validation was carried out by the Bootstrap method with 1 000 repeated samplings,and the area under the curve of the model internal validation was still as high as 0.939,proving that the model had good stability.(5)Through the decision curve,it is found that within the probability threshold range of 1％to 92％,the model can obtain the maximum net benefit value.(6)The SHAP analysis results show that among the risk factors analyzed in this study,the location of the fracture line serves as the most significant predictor of femoral head necrosis following internal fixation with cannulated screws in femoral neck fractures,and subcapital fractures are extremely prone to femoral head necrosis after surgery.(7)It is concluded that the validated prediction model demonstrates strong discriminative power and reliability,offering practical clinical utility.It serves as a useful reference tool for short-term risk assessment of femoral head necrosis following internal fixation of femoral neck fractures.

BACKGROUND:The most common complication of traumatic femoral neck fractures after internal fixation is femoral head necrosis.Currently,many studies have reported on the risk factors that affect the occurrence and development of postoperative femoral head necrosis,but there is still a lack of tools to predict the risk of femoral head necrosis after internal fixation of femoral neck fractures.OBJECTIVE:To develop a predictive model that estimates the risk of femoral head necrosis shortly after patients with femoral neck fractures receive cannulated screw internal fixation.METHODS:A retrospective analysis reviewed clinical records of 172 patients who underwent cannulated screw internal fixation for femoral neck fractures at Department of Orthopedics of Mianyang Central Hospital from January 2013 to June 2023.Patients were categorized into two groups based on the presence or absence of femoral head necrosis within one year post-operation:the necrosis group and the non-necrosis group.Univariate analysis,Lasso regression,and multivariate Logistic regression techniques were employed to identify the determinants of femoral head necrosis.A nomogram prediction model was constructed using R language's"rms"package,version 4.0.The receiver operating characteristic curve was used to evaluate the discriminatory ability of the model.The Hosmer-Lemeshow test was used to evaluate the goodness of fit of the model,and the decision curve analysis was used to determine its clinical application benefits.Internal validation of the study was conducted using the Bootstrap method,involving 1 000 repeated samplings.To delve deeper into the primary factors influencing femoral head necrosis post-internal fixation of the femoral neck,this paper employed the SHAP method for data set analysis.RESULTS AND CONCLUSION:(1)The risk factors leading to femoral head necrosis in the short term after cannulated screw fixation of femoral neck fractures include:smoking,diabetes,Garden classification,fracture line location,reduction quality,age,and operation time.(2)The prediction model demonstrated robust performance,evidenced by an area under the curve of 0.940(95％Confidence Interval:0.903 to 0.977),indicating a high level of prediction accuracy.The model achieved a sensitivity of 90.2％and a specificity of 87.6％,indicating that its diagnostic performance was stable.The Hosmer-Lemeshow goodness-of-fit test yielded a chi-square value of 6.593 with a P-value of 0.581,confirming that the model's predictions closely align with the observed outcomes.(3)The calibration curve of the model also performed well,and its overall trend was very close to the ideal curve,further proving the high accuracy of the model.(4)The internal validation was carried out by the Bootstrap method with 1 000 repeated samplings,and the area under the curve of the model internal validation was still as high as 0.939,proving that the model had good stability.(5)Through the decision curve,it is found that within the probability threshold range of 1％to 92％,the model can obtain the maximum net benefit value.(6)The SHAP analysis results show that among the risk factors analyzed in this study,the location of the fracture line serves as the most significant predictor of femoral head necrosis following internal fixation with cannulated screws in femoral neck fractures,and subcapital fractures are extremely prone to femoral head necrosis after surgery.(7)It is concluded that the validated prediction model demonstrates strong discriminative power and reliability,offering practical clinical utility.It serves as a useful reference tool for short-term risk assessment of femoral head necrosis following internal fixation of femoral neck fractures.

ObjectiveThe frequency difference limen (FDL) serves as a fundamental metric utilized for effectively quantifying the precise perceptual capabilities of the central auditory system. However, traditional measurement methods rely heavily on the active behavioral responses of subjects and are consequently highly susceptible to the negative influence of confounding subjective factors. Furthermore, existing research paradigms frequently employ uniform stimulus configurations that overlook critical individual perceptual differences. Based on brain-computer interface (BCI) technology, this comprehensive study aims to establish an objective and quantitative evaluation method for auditory frequency discrimination by systematically analyzing and decoding the specific neural responses elicited at the exact threshold state. MethodsWe designed a personalized rapid serial auditory presentation (RSAP) paradigm customized based on each individual’s precise FDL. A cohort of eleven healthy participants was recruited to evaluate the paradigm using pure-tone sequences at a baseline frequency of 4 000 Hz. This experimental paradigm simulates a realistic auditory perception environment through the continuous presentation of acoustic stimuli, thereby allowing for an in-depth investigation into the specific neural representations evoked by weak frequency deviations at the threshold state. Given that auditory stimulus-evoked response features exhibit complex and differentiated spatiotemporal distribution patterns across multiple frequency domains, this study further deeply integrates the cross-scale feature interaction module with the dynamic spatiotemporal attention allocation strategy, innovatively proposing the Multi-Scale Spatial-Temporal Dual Attention Network (MS-STAMNet). Specifically, the network constructs parallel processing branches with multiple receptive fields and introduces a dynamic adaptive weighting strategy to precisely localize core neural activity signals, further deeply integrating multi-scale information through cross-branch feature information interaction to achieve robust single-trial decoding of weak auditory evoked responses. ResultsThe comprehensive electrophysiological data analysis demonstrated that subtle auditory frequency deviation stimuli presented at the threshold level successfully elicited pronounced N2 and P3 event-related potential features, reflecting pre-attentive mismatch detection and subsequent cognitive evaluation, which were prominently distributed over the frontal, central, and temporal regions of the scalp. In the complex time-frequency domain, the extracted neural response characteristics exhibited distinct, statistically significant event-related synchronization within both the low-frequency δ and θ frequency bands, which was simultaneously accompanied by a widespread, prominent event-related desynchronization within the higher α band. A comparative analysis of model performance demonstrated that MS-STAMNet achieved an average unweighted average recall (UAR) of (69.67±6.12)% and area under the curve (AUC) of 0.761 8±0.07, significantly outperforming the established baseline models such as EEGNet and PLNet. Furthermore, a distinct dissociation phenomenon was verified between neural decoding and behavioral performance through regression analysis (R²=0.016, P=0.709), indicating that this model can effectively capture the implicit features of subtle frequency deviations, even when they fail to trigger explicit conscious responses. Additionally, attention weight visualization analysis further reveals the highly accurate focus of the network on key features concentrated over the bilateral temporal and fronto-parietal regions. ConclusionThis study systematically and comprehensively uncovers the multi-dimensional spatiotemporal evolutionary patterns of complex neural responses processing subtle acoustic variations under long-sequence threshold auditory stimulation. Concurrently, it verifies the efficacy and robustness of the proposed MS-STAMNet architecture in accurately deciphering weak, single-trial electroencephalogram signals amidst complex background noise. Ultimately, these neurophysiological and algorithmic findings lay a solid theoretical and methodological foundation for the objective and quantitative evaluation of individual auditory cognitive capabilities in clinical applications, transcending the fundamental limitations of traditional behavioral paradigms and providing robust technical support for future auditory research and related clinical assessments.

Objective:To study the correlation between iodine level in drinking water and conventional water quality indicators.Methods:From June 2017 to July 2018, a simple random sampling method was used to select administrative villages (communities) from 88 counties (cities, districts) in Guizhou Province with a sampling size greater than 5%. One drinking water sample was collected from each administrative village (community), and conventional water quality indicators (including fluorine, aluminum, mercury, selenium, sulfate, total dissolved solids and total hardness) were tested in accordance with the methods outlined in the "Standards for Drinking Water Quality" (GB 5749-2006). The cerium sulfate catalytic spectrophotometric method was employed to test drinking water iodine level. Spearman method was utilized to analyze the correlation between iodine level in drinking water and conventional water quality indicators.Results:A total of 904 drinking water samples were tested, with a median iodine level of 1.90 μg/L and a range of 0.10 - 36.70 μg/L. There were 899 administrative villages (communities) with a water iodine level of less than 10 μg/L, accounting for 99.45%. There were only 5 administrative villages (communities) with a water iodine level of greater than 10 μg/L, accounting for 0.55%. Correlation analysis revealed that in Guizhou Province, the iodine level in drinking water was positively correlated with the levels of fluorine, aluminum, sulfate, total dissolved solids, and total hardness [correlation coefficients ( r) = 0.11, 0.07, 0.07, 0.08, 0.07, P < 0.05], and was a negatively correlated with mercury and selenium levels ( r = - 0.12, - 0.12, P < 0.001). Conclusions:External environment in Guizhou Province is generally deficient in iodine. The iodine level in drinking water is positively correlated with the levels of fluorine, aluminum, sulfate, total dissolved solids, and total hardness, and negatively correlated with the levels of mercury and selenium.

Objective To explore the relationship between triglyceride-glucose(TyG)index and hypertension in patients with cerebral hemorrhage.Methods A total of 1718 patients with cere-bral hemorrhage admitted to our hospital from January,2013 to May,2023 were enrolled in this study.According to the TyG index quartile,437 cases were assigned into Q1 group(≤8.375),424 cases into Q2 group(TyG index 8.376～8.737),429 cases into Q3 group(TyG index 8.738～9.087),and 428 cases into Q4 group(≥9.088).The general clinical data were compared in the four groups.Logistic regression analysis was used to study the correlation between TyG index and hy-pertension.Results There were significant differences among the four groups in terms of age,hy-pertension,diabetes,SBP,DBP,TC,TG,HDL-C,LDL-C,FBG,glycated hemoglobin and TyG in-dex(P＜0.05,P＜0.01).Logistic regression analysis showed that when the TyG index was a con-tinuous variable,it was significantly correlated with the risk of hypertension(OR=1.999,95％CI:1.393-2.869,P=0.001).When the index was used as a categorical variable,with Q1as a ref-erence,TyG index in Q3 and Q4 was associated with an increase in OR of hypertension(OR=1.869,95％CI:1.220-2.865,P=0.004;OR=1.844,95％CI:1.125-3.020,P=0.015).After ad-justing cofounders,the association of TyG index and risk of hypertension was stronger in the fe-males(OR=2.618,95％CI:1.312-5.221,P=0.006)than the males(OR=1.783,95％CI:1.151-2.761,P=0.010),and in the patients ≥65 years old(OR=3.277,95％CI:1.600-6.741,P=0.001)than those＜65 years old(OR=1.782,95％CI:1.076-2.949,P=0.025).Conclusion TyG index is closely associated with hypertension in patients with cerebral hemorrhage,especially in women and elderly.

Objective To explore the effect of Rhizoma Polygonati(RP)on arterial aging in naturally aging Wistar rats.Methods SPF Wistar rats aged 72 weeks were divided randomly divided into 4 groups:an old group and RP low,medium,and high-dose groups(n=14 rats per group).Another 14 male SPF Wistar rats aged 8～12 weeks were selected as the young group.Rats in the RP high,medium,and low-dose groups were administered with 4,2,and 1 g/kg RP,respectively,by gavage,and rats in the old and young groups were given the same amount of distilled water once a day for 12 weeks.Seven rats from each group were sacrificed under anesthesia at weeks 4 and 12 and aortas were isolated.The relative smooth muscle cell(SMC)and collagen fiber(CF)contents were analyzed,total antioxidant capacity(T-AOC),glutathione peroxidase(GSH-Px),superoxide dismutase(SOD),and malondialdehyde(MDA)levels were measured,and the expression levels of cell cycle-associated proteins in arterial tissue were detected by Western Blot.Results Rats in the old group showed obvious signs of vascular aging but there was no significant changes in arterial vascular tissue indexes in the old group with increased age.Aortas were obviously injured,relative contents of SMC and CF were significantly increased(P＜0.01),T-AOC,SOD,and GSH-Px contents were significantly decreased and MDA was increased(P＜0.01)in the old group compared with the young group at 4 and 8 weeks,and expression levels of cell cycle-associated proteins were significantly up-regulated(P＜0.01).RP intervention significantly decreased the relative SMC and CF contents and MDA levels(P＜0.05 or P＜0.01)and significantly increased T-AOC,SOD,and GSH-Px(P＜0.05 or P＜0.01).Expression levels of cell cycle-associated proteins were also significantly decreased(P＜0.05 or P＜0.01).High-dose RP had the greatest effect.Conclusions Arterial aging is relatively stable in the short term in naturally aging rats.RP could delay arterial aging in naturally aging rats by regulating the level of oxidative stress and the expression of cell cycle-associated proteins.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 ? by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Ⅰa-loop-helix Ⅰβ motif which cor-responds to helix Ⅰ of other P450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,the γ-domain.The structure reveals a homodimer in which the γ-domain of one molecule interacts with the β-domain of another.The plane of heme group makes an angle of ap-proximately 40° with the helix Ⅰa-loop-helix Ⅰβ motif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recogni-tion.Phe-301,Ser-303 and Gly-305 from the helix Ⅰa-loop-helix Ⅰβ motif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.

Objective This study aims to analyze the factors influencing per capita current health expenditure in Guizhou Province from 2016 to 2022 using the gray correlation analysis method.Methods Based on the"SHA2011"accounting results of current health expenditure in Guizhou Province,as well as data from the"Guizhou Statistical Yearbook"and"Guizhou Health Statistical Yearbook",the gray correlation analysis method was used to analyze the factors influencing per capita current health expenditure in Guizhou Province from 2016 to 2022.Results The factors with the highest correlation to per capita current health expenditure in Guizhou Province were health expenditure(0.829),followed by the number of health technical personnel per thousand people(0.715),the number of practicing(assistant)physicians per thousand people(0.705),and per capita GDP(0.704).The factor with the lowest correlation was the proportion of the tertiary industry to GDP(0.543).Conclusion Health expenditure investment has the strongest correlation with per capita current health expenditure in Guizhou Province.Health re-source investment and health service capacity are the main influencing factors of per capita current health expenditure in Guizhou Province.At the same time,the impact of economic and social factors on current health expenditure should be fully recognized.

Objective:To investigate the effect of monocular form deprivation (MD) on the distribution density of neuregulin-1 (NRG1) + and NRG1 - parvalbumin (PV) neurons in the primary visual cortex of mice during the critical period of visual development. Methods:Twelve healthy 28-day-old SPF male C57BL/6J mice were randomly divided into control group and MD group by the random number table method, with 6 mice in each group.After MD on postnatal day (P) 28, the MD group was fed until P32, while the control group was fed normally until P32.All mice were sacrificed by cervical dislocation after cardiac perfusion, and brain tissues were quickly collected.After fixation overnight, brain slices were subjected to PV and NRG1 immunofluorescence staining to observe and compare the differences in the distribution density of PV + , PV + /NRG1 + and PV + /NRG1 - neurons in both sides of the primary visual cortex (V1) area of the two groups.This study was conducted in accordance with the Regulations on the Administration of Experimental Animals (2017 Revision), and the study protocol was approved by the Institutional Animal Care and Use Committee of Tianjin Medical University (No.TMUaMEC2022004). Results:Immunofluorescence staining showed that the density of PV + and PV + /NRG1 + neurons was (137.8±4.3), (108.8±4.1), (137.4±4.0)/mm 2 in the contralateral V1 area of the control group, MD group and the ipsilateral V1 area of the MD group, and that of PV + /NRG1 + neurons was (112.0±4.6), (82.1±4.7) and (113.6±5.7)/mm 2, respectively, with statistically significant overall differences ( F=15.88, 12.53; both P<0.001).PV + neuron density and PV + /NRG1 + neuron density in the contralateral V1 area of the MD group were significantly lower than in the control group and in the ipsilateral V1 area of the MD group (all P<0.001).There was no difference in PV + /NRG1 - neuron density between the two groups ( F=0.20, P>0.05). Conclusions:PV + /NRG1 + neurons may be the main cell type regulating the development of primary visual cortex during the critical period.