Objective To construct risk models for predicting the occurrence of high altitude de-acclimatization syndrome(HADAS)in the population returning from the plateau to the plain based on different machine learning algorithms and validate the predicting efficiency of these models.Methods Field or online surveys were conducted on the individuals who had ended their high-altitude living and returned to the plain areas from November 2020 to February 2024.Basic information,chronic mountain sickness(CMS),HADAS symptoms and other data were collected.With the inclusion and exclusion criteria,totally 1 095 individuals were subjected and assigned into the modeling group.Positive events were defined as HADAS score>5.Then the modelling group was divided into a training set(n=766)and an internal test set(n=329)in a 7∶3 ratio.Least absolute shrinkage and selection operator(LASSO)regression was used to select independent variables.Risk prediction models for high-altitude adaptation symptoms were built based on 8 machine learning methods,including multiple factor logistic regression(LR),decision tree(DT),random forest(RF),eXtreme gradient boosting(XGB),support vector machine(SVM),K-nearest neighbor(KNN),light gradient boosting(LGB)and na?ve bayes(NB).The models were compared and evaluated using receiver operating characteristic(ROC)curves,calibration curves and confusion matrices in the internal test set.The final model was presented using a nomogram or Shapley additive explanations(SHAP)algorithm.In August 2024,another 132 individuals who returned to the plains and met the same criteria were recruited and served as the external validation group.Results There were 549 individuals(50.14%)out of the 1 095 subjects having HADAS symptoms.LASSO regression identified CMS score,age and duration of high-altitude residence as significant predictors.Among the 8 machine learning algorithms,the LR model was identified as the best,with an area under the curve(AUC)value of 0.819(95%CI:0.789～0.850)and 0.841(95%CI:0.799～0.884),and an F1 score of 0.801 in the internal test set,respectively,and the AUC value and F1 score of the LR model were the largest among the 8 models in the internal test set.Spiegelhalter Z test of the calibration curve of the LR model indicated that its P=0.703 in the training set while P=0.281 in the internal test set.The AUC value of the LR model was 0.867(95%CI:0.765～0.969)in the external validation set.Conclusion The LR model constructed based on indicators including CMS score,age and duration of high-altitude residence has a good overall performance in the internal test set,and good discriminating effect in the external validation set.The constructed nomogram is convenient for application.

Severe open tibiofibular fractures account for approximately 28.1% of all open fractures. Among them, Gustilo-Anderson type IIIB/C fractures present significant clinical challenges due to associated bone and soft tissue defects, high infection rates, and risk of amputation. Inadequate preoperative assessment may lead to suboptimal emergency surgical planning or intraoperative complications. Historically, external fixation was often preferred, but this approach has been associated with limitations such as restricted joint mobility, delayed bone union, joint stiffness, and disuse osteoporosis, resulting in poor functional recovery. With advancements of debridement techniques, standardization of antibiotic use, and popularization of early soft tissue coverage, early internal fixation has gained broader acceptance. Nevertheless, controversies persist regarding the choice of fixation method, timing of definitive fixation, use of reamed versus unreamed intramedullary nailing, and necessity of fibular fixation. To standardize the diagnosis and early management of severe open tibiofibular fractures, reduce complication rates, and improve functional recovery, the Society of Microsurgery of the Chinese Medical Association organized a panel of domestic experts to develop the Evidence-based guideline for the diagnosis and early fixation of severe open tibiofibular fractures ( version 2025), using evidence-based methodology. The guidelines provided 12 recommendations covering diagnostic and early fixation strategies of severe open tibiofibular fractures, aiming to provide clinicians with scientifically grounded and standardized guidance.

Objective:To establish an ion chromatography-integrated amperometric detection method for iodide in water.Methods:After the water sample was filtered through a filter membrane, the AS 11-HC anion chromatography column of ion chromatography method was used to separate iodide ions under the conditions of 70 mmol/L sodium hydroxide solution as the eluent, injection volume of 100 μl, column temperature of 30 ℃, and flow rate of 1.0 ml/min. The results were determined by silver working electrode integral amperometric detection method. Under the optimized experimental conditions, methodological evaluations such as method calibration curves, detection limits, quantification limits, precision, and accuracy were conducted.Results:Iodide followed a square correction curve within the concentration range of 0 - 100 μg/L, with a correlation coefficient ( r) > 0.999 9. The detection limit of the method was 0.30 μg/L, and the quantification limit was 1.00 μg/L. The determination results of the national standard substances GBW09113f and GBW09114f for iodine composition analysis in water were within the reference range [(8.4 ± 1.2), (55 ± 6) μg/L]. The recovery rates of low, medium, and high concentration spiked samples with low background values ranged from 91.7% to 97.2%, and the relative standard deviation ranged from 0.40% to 1.60%. Conclusion:This method has the characteristics of simple water sample pretreatment, high sensitivity, and good accuracy, which can meet the determination of trace iodides in bulk water samples for iodine deficiency disorders monitoring.

Cemental tear is a rare and indetectable condition unless obvious clinical signs present with the involvement of surrounding periodontal and periapical tissues. Due to its clinical manifestations similar to common dental issues, such as vertical root fracture, primary endodontic diseases, and periodontal diseases, as well as the low awareness of cemental tear for clinicians, misdiagnosis often occurs. The critical principle for cemental tear treatment is to remove torn fragments, and overlooking fragments leads to futile therapy, which could deteriorate the conditions of the affected teeth. Therefore, accurate diagnosis and subsequent appropriate interventions are vital for managing cemental tear. Novel diagnostic tools, including cone-beam computed tomography (CBCT), microscopes, and enamel matrix derivatives, have improved early detection and management, enhancing tooth retention. The implementation of standardized diagnostic criteria and treatment protocols, combined with improved clinical awareness among dental professionals, serves to mitigate risks of diagnostic errors and suboptimal therapeutic interventions. This expert consensus reviewed the epidemiology, pathogenesis, potential predisposing factors, clinical manifestations, diagnosis, differential diagnosis, treatment, and prognosis of cemental tear, aiming to provide a clinical guideline and facilitate clinicians to have a better understanding of cemental tear.
Humans ; Dental Cementum/injuries* ; Consensus ; Diagnosis, Differential ; Cone-Beam Computed Tomography ; Tooth Fractures/therapy*

Objective:To establish a method for determination of fluoride in water using a fully automated biochemical analyzer (abbreviated as this method).Methods:Based on the parameters of the fully automatic biochemical analyzer, appropriate reagent volumes and reaction time were optimized to determine fluoride ions in water within the standard curve range (0.0 - 2.0 mg/L). The method was validated through evaluation of linear range, detection limit, precision, accuracy, and comparative analysis with the manual measurement results of fluoride reagent spectrophotometric method specified in the "Standard Examination Methods for Drinking Water - Part 5: Inorganic Nonmetallic indices" (GB/T 5750.5-2023).Results:Within the range of 0.0 - 2.0 mg/L fluoride mass concentration, the absolute values of the correlation coefficients were > 0.999 0 and the detection limit of this method was 0.082 mg/L. The relative standard deviation for the determination of fluoride level in water samples with low, medium and high fluoride mass concentrations was 4.03%, 2.16% and 1.68%, respectively. The spiked recovery rates were 98.1%, 99.5%, and 100.2%, respectively. There was no statistically significant difference between the results obtained by this method and manual measurement ( t = 1.07, P = 0.295). Conclusion:This method exhibits high sensitivity, accuracy, and efficiency in detecting fluoride, enabling rapid sample detection through instrumental automation instead of manual operation.

Objective:To establish a method for determination of fluoride in water using a fully automated biochemical analyzer (abbreviated as this method).Methods:Based on the parameters of the fully automatic biochemical analyzer, appropriate reagent volumes and reaction time were optimized to determine fluoride ions in water within the standard curve range (0.0 - 2.0 mg/L). The method was validated through evaluation of linear range, detection limit, precision, accuracy, and comparative analysis with the manual measurement results of fluoride reagent spectrophotometric method specified in the "Standard Examination Methods for Drinking Water - Part 5: Inorganic Nonmetallic indices" (GB/T 5750.5-2023).Results:Within the range of 0.0 - 2.0 mg/L fluoride mass concentration, the absolute values of the correlation coefficients were > 0.999 0 and the detection limit of this method was 0.082 mg/L. The relative standard deviation for the determination of fluoride level in water samples with low, medium and high fluoride mass concentrations was 4.03%, 2.16% and 1.68%, respectively. The spiked recovery rates were 98.1%, 99.5%, and 100.2%, respectively. There was no statistically significant difference between the results obtained by this method and manual measurement ( t = 1.07, P = 0.295). Conclusion:This method exhibits high sensitivity, accuracy, and efficiency in detecting fluoride, enabling rapid sample detection through instrumental automation instead of manual operation.

Severe open tibiofibular fractures account for approximately 28.1% of all open fractures. Among them, Gustilo-Anderson type IIIB/C fractures present significant clinical challenges due to associated bone and soft tissue defects, high infection rates, and risk of amputation. Inadequate preoperative assessment may lead to suboptimal emergency surgical planning or intraoperative complications. Historically, external fixation was often preferred, but this approach has been associated with limitations such as restricted joint mobility, delayed bone union, joint stiffness, and disuse osteoporosis, resulting in poor functional recovery. With advancements of debridement techniques, standardization of antibiotic use, and popularization of early soft tissue coverage, early internal fixation has gained broader acceptance. Nevertheless, controversies persist regarding the choice of fixation method, timing of definitive fixation, use of reamed versus unreamed intramedullary nailing, and necessity of fibular fixation. To standardize the diagnosis and early management of severe open tibiofibular fractures, reduce complication rates, and improve functional recovery, the Society of Microsurgery of the Chinese Medical Association organized a panel of domestic experts to develop the Evidence-based guideline for the diagnosis and early fixation of severe open tibiofibular fractures ( version 2025), using evidence-based methodology. The guidelines provided 12 recommendations covering diagnostic and early fixation strategies of severe open tibiofibular fractures, aiming to provide clinicians with scientifically grounded and standardized guidance.

Objective:To establish an ion chromatography-integrated amperometric detection method for iodide in water.Methods:After the water sample was filtered through a filter membrane, the AS 11-HC anion chromatography column of ion chromatography method was used to separate iodide ions under the conditions of 70 mmol/L sodium hydroxide solution as the eluent, injection volume of 100 μl, column temperature of 30 ℃, and flow rate of 1.0 ml/min. The results were determined by silver working electrode integral amperometric detection method. Under the optimized experimental conditions, methodological evaluations such as method calibration curves, detection limits, quantification limits, precision, and accuracy were conducted.Results:Iodide followed a square correction curve within the concentration range of 0 - 100 μg/L, with a correlation coefficient ( r) > 0.999 9. The detection limit of the method was 0.30 μg/L, and the quantification limit was 1.00 μg/L. The determination results of the national standard substances GBW09113f and GBW09114f for iodine composition analysis in water were within the reference range [(8.4 ± 1.2), (55 ± 6) μg/L]. The recovery rates of low, medium, and high concentration spiked samples with low background values ranged from 91.7% to 97.2%, and the relative standard deviation ranged from 0.40% to 1.60%. Conclusion:This method has the characteristics of simple water sample pretreatment, high sensitivity, and good accuracy, which can meet the determination of trace iodides in bulk water samples for iodine deficiency disorders monitoring.

Objective:To establish an automatic potentiometric method for determination of fluoride in urine.Methods:The fluorine level in human urine was determined by an automatic potentiometric titrator. Methodological experimental analysis of the linear range, detection limit, precision, and accuracy (quality control sample testing and actual sample spiking recovery experiment) of the method were carried out. The determination results of 33 urine samples were compared with those of the national health industry standard Determination of Fluoride in Urine - Ion Selective Electrode Method (WS/T 89-2015).Results:The linear range of the standard curve of urine fluoride in the automatic potentiometric determination method was 0.1 - 10.0 mg/L. The range of linear correlation coefficient ( r) was 0.999 6 to 0.999 9. The minimum detection limit of urine fluoride was 0.01 mg/L (sampling volume was 10.0 ml). The relative standard deviation ( RSD) range for precision experiments was 0.00% to 3.45%. The quality control samples of the national urine fluoride external quality control assessment in 2022 were determined, and the results were within the range of the consensus value. The spiked recovery experiment was carried out, the recovery rate ranged from 100.0% to 104.4%, with a total average recovery rate of 102.1%. The method comparison experiment showed that there was no statistically significant difference between the test results of automatic potentiometric method and the standard method recommended by the national urine fluoride health industry ( t = - 0.90, P = 0.375). Conclusions:A method has been successfully established, achieving automation of the reagent addition and detection process of urine fluoride samples after sampling. It has the characteristics of wide linear range, low detection limit, good precision, and high accuracy, and is suitable for rapid and automatic determination fluoride level of large quantities of urine samples.

Objective:To establish a new method for antimony cerium catalytic spectrophotometric detection (referred to as the new method) of urinary iodine.Methods:By utilizing the efficient catalytic ability of iodine for the oxidation-reduction reaction of antimony and cerium, a new method was applied to conduct linear relationship fitting curve, detection limit, pecision, accuracy and other experiments within the range of 0 - 300 μg/L urine iodine mass concentration. The method was compared with the Arsenic Cerium Catalytic Spectrometric Method (WS/T 107.1-2016) recommended national industry standard.Results:In the range of 0 - 300 μg/L urine iodine mass concentration, the correlation coefficients│ r│ of the fitted curves were > 0.999 0, and the qualitative detection limit was 7.96 μg/L (with a sampling volume of 0.25 ml). Four actual urine samples with different iodine mass concentrations were selected for precision experiments, and the relative standard deviation ( RSD) of the detection precision ranged from 0.96% to 2.87%, all < 5%. The actual urine sample spiked recovery range from 99.62% to 103.88%, with an overall average recovery rate of 101.75%. Two methods were used to detect 30 urine samples, and the difference in results was not statistically significant ( t = 0.68, P = 0.501). Conclusions:The new method has high reaction sensitivity and accuracy, avoiding the use of highly toxic substance arsenic trioxide. The antimony reagent used is safe, and the environmental pollution caused by waste liquid discharge is small. The detection steps are similar to Arsenic Cerium Catalytic Spectrometric Method, the laboratory urine iodine detection personnel do not need special training to operate and use it, which is suitable for the application and promotion of urine iodine detection in grassroots iodine deficiency disorders monitoring work.