Objective:This study evaluates the horizontal sound localization ability of young and middle-aged individuals with symmetric sensorineural hearing loss (SNHL) in noisy environments. It also examines the impact of hearing loss severity and signal-to-noise ratio (SNR) on localization accuracy.Methods:In this cross-sectional study, conducted from April 2023 to April 2024, 135 young and middle-aged patients (73 males and 62 females, aged 18-60 years) with SNHL who sought care at Beijing Chaoyang Hospital, were categorized into mild, moderate, and moderate-to-severe hearing loss groups (45 per group), with 45 normal-hearing controls (23 males and 22 females, aged 20-60 years). Participants completed localization tasks in quiet and noisy environments with SNR levels of 5 dB, 0 dB, -5 dB, and-10 dB. Root mean square error (RMSE) was used to measure localization accuracy. Repeated measures ANOVA assessed the effects of hearing loss and SNR on RMSE, while, Pearson correlation evaluated the relationship between binaural 4-frequency pure-tone average (4fPTA) and RMSE. Multiple linear regression analyzed the predictive role of 4fPTA and age.Results:(1) Two-way repeated measures ANOVA showed that both hearing loss severity and SNR significantly affected RMSE ( F=92.67, P<0.01; F=430.29, P<0.01), with a significant interaction between the two factors( F=92.67, P<0.01). (2) RMSE increased with hearing loss severity. At SNRs of 5 dB, 0 dB, and-5 dB, the moderate-to-severe group had significantly higher RMSE than the mild and moderate groups ( P<0.01). No significant differences were found between mild and moderate groups ( P=0.53, 0.57, 0.22). At-10 dB SNR, significant differences were observed across all groups ( P<0.01). (3) RMSE increased non-linearly as SNR decreased. Mean RMSE values under quiet conditions and at SNRs of 5 dB, 0 dB, -5 dB, and-10 dB were (7.43±5.01)°, (9.80±5.74)°, (11.60±6.22)°, (14.56±7.07)°, and (18.74±8.02)°, respectively. (4) RMSE was significantly positively correlated with binaural 4fPTA ( r=0.54-0.58, P<0.01). Multiple linear regression analysis indicated that the binaural average 4fPTA significantly predicted RMSE ( P<0.01), explaining 30.5%-34.1% of RMSE variance. Age did not significantly contribute to RMSE variation. Conclusions:The degree of hearing loss and background noise SNR significantly affect horizontal sound localization in young and middle-aged SNHL patients. RMSE increases with hearing loss severity and decreases with higher SNR. The interaction between hearing loss and SNR is significant, and RMSE correlates with binaural 4fPTA. However, the regression model based on 4fPTA and age explains only part of the RMSE variance, suggesting other contributing factors.

Objective:To explore the associated factors for membranous nephropathy (MN) patients with IgM deposition, and to construct a prediction model.Methods:This study was a retrospective cohort study. Patients diagnosed with MN with IgM deposition by renal biopsy in the Fourth Hospital of Hebei Medical University from February 2017 to December 2023 were retrospectively included. Clinical and pathological data were collected. The study population was randomized into a training set and a validation set at a 7:3 ratio. The endpoint event was defined as the remission of MN, and the patients were divided into remission group and non-remission group to compare the clinical and pathological examination results. Least absolute shrinkage and selection operator regression analysis and Cox regression analysis were used to explore the associated factors of poor prognosis of MN patients with IgM deposition. Internal validation was conducted using the validation set data. The clinical efficacy of the predictive model was evaluated by calculating the area under the receiver operating characteristic (ROC) curve and generating calibration curves. The total nomogram score for each patient was calculated based on the training set data, and the predictive performance was assessed by plotting the ROC curve. Patients were then stratified into low-risk and high-risk groups according to the optimal cut-off value derived from the ROC analysis of the total nomogram score. Kaplan-Meier survival analysis was performed to compare the remission rate between the two groups. Model performance was evaluated using the validation set.Results:A total of 200 MN patients with IgM deposition were included, and 49.0% of them achieved clinical remission. In the training set, statistically significant differences were observed in 24-hour urine protein quantification ( Z=-2.638, P=0.008), renal arteriolar wall thickening ( χ2=6.891, P=0.009), the proportion of patients receiving immunosuppressive therapy ( χ2=21.381, P<0.001), and the proportion of patients treated with corticosteroids combined with cyclophosphamide ( χ2=10.107, P=0.001). Through least absolute shrinkage and selection operator regression and Cox regression, 2 factors associated with clinical remission in MN patients with IgM deposition were simultaneously identified from 16 potential associated factors, including the use of immunosuppressants ( HR=3.823, 95% CI 2.055-7.113, P<0.001), and renal arteriolar wall thickening ( HR=0.428, 95% CI 0.221-0.831, P=0.012). Incorporating the clinical measurement of phospholipase A2 receptor (PLA2R) antibodies, a predictive model was established. The performance of the model was evaluated using the training dataset, yielding an area under the ROC curve of 0.731 (95% CI 0.648-0.814), with a sensitivity of 88.7% and a specificity of 55.1%. The optimal cut-off value was a total nomogram score of 41.7 points. The Kaplan-Meier survival analysis showed that the remission rate was significantly higher in the low-risk group than that of the high-risk group (Log-rank test, χ2=33.525, P<0.001). Model validation was performed using the validation dataset, which showed an AUC of 0.715 (95% CI 0.591-0.839), sensitivity of 70.4%, and specificity of 63.6%. Similarly, the Kaplan-Meier survival analysis demonstrated a significantly higher remission rate in the low-risk group than in the high-risk group (Log-rank test, χ2=8.467, P=0.004). Conclusion:A nomogram predictive model for remission of MN patients with IgM deposition, based on serum PLA2R antibody levels, the use of immunosuppressive therapy, and renal arteriolar wall thickening is developed. The model demonstrates a moderate clinical applicability.

OBJECTIVE To investigate the relationship between azimuth direction,angular intervals,and the accuracy of azimuthal sound source localization.METHODS Fifteen young subjects with normal hearing were tested using nine azimuth settings.The test results were presented as root mean square error and percentage confusion.RESULTS The confusion rate under high-frequency narrowband noise was significantly higher than that under broadband noise and three-syllable words.In the frontal direction,statistically significant differences were observed between the 20° and 10° intervals,as well as between the 20° and 15° intervals(P<0.05),but no significant difference was found between the 10° and 15° intervals(P>0.05).In the lateral and rear directions,statistically significant differences were found between the 30° and 15° intervals,as well as between the 30° and 20° intervals(P<0.05),but no significant difference was found between the 15° and 20° intervals(P>0.05).Statistically significant differences were observed between the frontal direction and both the lateral and rear directions(P<0.05),but no significant difference was found between the lateral and rear directions(P>0.05).CONCLUSION Using stimuli that contain broader bandwidth cues can more accurately reflect the subject's horizontal localization ability.For source azimuth identification tests using broadband noise and three-syllable words,it is recommended to use a 15° interval in the frontal direction,and a 20° interval in the lateral and rear directions.The frontal and lateral directions can be preferred for testing.

Objective:This study evaluates the horizontal sound localization ability of young and middle-aged individuals with symmetric sensorineural hearing loss (SNHL) in noisy environments. It also examines the impact of hearing loss severity and signal-to-noise ratio (SNR) on localization accuracy.Methods:In this cross-sectional study, conducted from April 2023 to April 2024, 135 young and middle-aged patients (73 males and 62 females, aged 18-60 years) with SNHL who sought care at Beijing Chaoyang Hospital, were categorized into mild, moderate, and moderate-to-severe hearing loss groups (45 per group), with 45 normal-hearing controls (23 males and 22 females, aged 20-60 years). Participants completed localization tasks in quiet and noisy environments with SNR levels of 5 dB, 0 dB, -5 dB, and-10 dB. Root mean square error (RMSE) was used to measure localization accuracy. Repeated measures ANOVA assessed the effects of hearing loss and SNR on RMSE, while, Pearson correlation evaluated the relationship between binaural 4-frequency pure-tone average (4fPTA) and RMSE. Multiple linear regression analyzed the predictive role of 4fPTA and age.Results:(1) Two-way repeated measures ANOVA showed that both hearing loss severity and SNR significantly affected RMSE ( F=92.67, P<0.01; F=430.29, P<0.01), with a significant interaction between the two factors( F=92.67, P<0.01). (2) RMSE increased with hearing loss severity. At SNRs of 5 dB, 0 dB, and-5 dB, the moderate-to-severe group had significantly higher RMSE than the mild and moderate groups ( P<0.01). No significant differences were found between mild and moderate groups ( P=0.53, 0.57, 0.22). At-10 dB SNR, significant differences were observed across all groups ( P<0.01). (3) RMSE increased non-linearly as SNR decreased. Mean RMSE values under quiet conditions and at SNRs of 5 dB, 0 dB, -5 dB, and-10 dB were (7.43±5.01)°, (9.80±5.74)°, (11.60±6.22)°, (14.56±7.07)°, and (18.74±8.02)°, respectively. (4) RMSE was significantly positively correlated with binaural 4fPTA ( r=0.54-0.58, P<0.01). Multiple linear regression analysis indicated that the binaural average 4fPTA significantly predicted RMSE ( P<0.01), explaining 30.5%-34.1% of RMSE variance. Age did not significantly contribute to RMSE variation. Conclusions:The degree of hearing loss and background noise SNR significantly affect horizontal sound localization in young and middle-aged SNHL patients. RMSE increases with hearing loss severity and decreases with higher SNR. The interaction between hearing loss and SNR is significant, and RMSE correlates with binaural 4fPTA. However, the regression model based on 4fPTA and age explains only part of the RMSE variance, suggesting other contributing factors.

Objective:To explore the associated factors for membranous nephropathy (MN) patients with IgM deposition, and to construct a prediction model.Methods:This study was a retrospective cohort study. Patients diagnosed with MN with IgM deposition by renal biopsy in the Fourth Hospital of Hebei Medical University from February 2017 to December 2023 were retrospectively included. Clinical and pathological data were collected. The study population was randomized into a training set and a validation set at a 7:3 ratio. The endpoint event was defined as the remission of MN, and the patients were divided into remission group and non-remission group to compare the clinical and pathological examination results. Least absolute shrinkage and selection operator regression analysis and Cox regression analysis were used to explore the associated factors of poor prognosis of MN patients with IgM deposition. Internal validation was conducted using the validation set data. The clinical efficacy of the predictive model was evaluated by calculating the area under the receiver operating characteristic (ROC) curve and generating calibration curves. The total nomogram score for each patient was calculated based on the training set data, and the predictive performance was assessed by plotting the ROC curve. Patients were then stratified into low-risk and high-risk groups according to the optimal cut-off value derived from the ROC analysis of the total nomogram score. Kaplan-Meier survival analysis was performed to compare the remission rate between the two groups. Model performance was evaluated using the validation set.Results:A total of 200 MN patients with IgM deposition were included, and 49.0% of them achieved clinical remission. In the training set, statistically significant differences were observed in 24-hour urine protein quantification ( Z=-2.638, P=0.008), renal arteriolar wall thickening ( χ2=6.891, P=0.009), the proportion of patients receiving immunosuppressive therapy ( χ2=21.381, P<0.001), and the proportion of patients treated with corticosteroids combined with cyclophosphamide ( χ2=10.107, P=0.001). Through least absolute shrinkage and selection operator regression and Cox regression, 2 factors associated with clinical remission in MN patients with IgM deposition were simultaneously identified from 16 potential associated factors, including the use of immunosuppressants ( HR=3.823, 95% CI 2.055-7.113, P<0.001), and renal arteriolar wall thickening ( HR=0.428, 95% CI 0.221-0.831, P=0.012). Incorporating the clinical measurement of phospholipase A2 receptor (PLA2R) antibodies, a predictive model was established. The performance of the model was evaluated using the training dataset, yielding an area under the ROC curve of 0.731 (95% CI 0.648-0.814), with a sensitivity of 88.7% and a specificity of 55.1%. The optimal cut-off value was a total nomogram score of 41.7 points. The Kaplan-Meier survival analysis showed that the remission rate was significantly higher in the low-risk group than that of the high-risk group (Log-rank test, χ2=33.525, P<0.001). Model validation was performed using the validation dataset, which showed an AUC of 0.715 (95% CI 0.591-0.839), sensitivity of 70.4%, and specificity of 63.6%. Similarly, the Kaplan-Meier survival analysis demonstrated a significantly higher remission rate in the low-risk group than in the high-risk group (Log-rank test, χ2=8.467, P=0.004). Conclusion:A nomogram predictive model for remission of MN patients with IgM deposition, based on serum PLA2R antibody levels, the use of immunosuppressive therapy, and renal arteriolar wall thickening is developed. The model demonstrates a moderate clinical applicability.

Objective:To analyze the current situation of dosimetry audits for linear accelerators in China comprehensively based on the literature, including the range of output dose deviation and the qualified rate of output dose deviation.Methods:Literature search including non-full-text was carried out in CNKI database for literature on output dose verification using dosimeter comparison and quality control test, respectively. Data extraction and analysis were carried out for each kind of eligible literature. The data on the number of tested linear accelerators, the number of qualified linear accelerators, the qualified rate of output dose deviation and the range of output dose deviation were extracted, and the total qualified rate of output dose deviation was calculated based on the total number of tested linear accelerators and the total number of qualified linear accelerators. The data on qualified rate of output dose deviation and output dose deviation in past years were sorted out and their trend was analyzed.Results:A total of 11 literatures using dosimeter comparison method for output dose verification were retrieved, and the total qualified rate of the output dose deviation reported in these literatures was 90.7%. The qualified rate of the output dose deviation in the early years was either as low as 75% or as high as 100%, and remained around 90% in recent years. A total of 19 literatures using quality control test method for output dose verification were retrieved, and the total qualified rate of X-ray and electron beam output dose deviation reported in these literatures was 86.5% and 78.4%, respectively. Of the 12 data on X-ray output dose qualified rate in 2014-2019, 8 were below 90.0% and 4 were above 90.0%. Of the 7 data on X-ray output dose qualified rate in 2020-2023, 2 were below 90.0% and 5 were greater than or equal to 90.0%. The qualified rate of electron beam output dose was 46.2%-80.0% before 2021 and 100% from 2021 to 2023.Conclusions:The qualified rate of the output dose deviation of linear accelerators in China reported in the literature in recent years is on the rise, but the total qualified rate of the output dose deviation of linear accelerators in China is still lower than in developed countries. In order to ensure the therapeutic effect of the patients undergoing radiotherapy, measures should be taken to reduce the output dose deviation of linear accelerators and improve the level of qualified rate of output dose verification.

Objective:To explore the drugs and clinical characteristics causing drug-induced liver injury (DILI) in recent years, as well as identify drug-induced liver failure, and chronic DILI risk factors, in order to better manage them timely.Methods:A retrospective investigation and analysis was conducted on 224 cases diagnosed with DILI and followed up for at least six months between January 2018 and December 2020. Univariate and multivariate logistic regression analyses were used to identify risk factors for drug-induced liver failure and chronic DILI.Results:Traditional Chinese medicine (accounting for 62.5%), herbal medicine (accounting for 84.3% of traditional Chinese medicine), and some Chinese patent medicines were the main causes of DILI found in this study. Severe and chronic DILI was associated with cholestatic type. Preexisting gallbladder disease, initial total bilirubin, initial prothrombin time, and initial antinuclear antibody titer were independent risk factors for DILI. Prolonged time interval between alkaline phosphatase (ALP) and alanine aminotransferase (ALT) falling from the peak to half of the peak (T 0.5ALP and T 0.5ALT) was an independent risk factor for chronic DILI [area under the receiver operating characteristic curve (AUC)?=?0.787, 95%CI: 0.697~0.878, P ?

Objective:To analyze the current situation of dosimetry audits for linear accelerators in China comprehensively based on the literature, including the range of output dose deviation and the qualified rate of output dose deviation.Methods:Literature search including non-full-text was carried out in CNKI database for literature on output dose verification using dosimeter comparison and quality control test, respectively. Data extraction and analysis were carried out for each kind of eligible literature. The data on the number of tested linear accelerators, the number of qualified linear accelerators, the qualified rate of output dose deviation and the range of output dose deviation were extracted, and the total qualified rate of output dose deviation was calculated based on the total number of tested linear accelerators and the total number of qualified linear accelerators. The data on qualified rate of output dose deviation and output dose deviation in past years were sorted out and their trend was analyzed.Results:A total of 11 literatures using dosimeter comparison method for output dose verification were retrieved, and the total qualified rate of the output dose deviation reported in these literatures was 90.7%. The qualified rate of the output dose deviation in the early years was either as low as 75% or as high as 100%, and remained around 90% in recent years. A total of 19 literatures using quality control test method for output dose verification were retrieved, and the total qualified rate of X-ray and electron beam output dose deviation reported in these literatures was 86.5% and 78.4%, respectively. Of the 12 data on X-ray output dose qualified rate in 2014-2019, 8 were below 90.0% and 4 were above 90.0%. Of the 7 data on X-ray output dose qualified rate in 2020-2023, 2 were below 90.0% and 5 were greater than or equal to 90.0%. The qualified rate of electron beam output dose was 46.2%-80.0% before 2021 and 100% from 2021 to 2023.Conclusions:The qualified rate of the output dose deviation of linear accelerators in China reported in the literature in recent years is on the rise, but the total qualified rate of the output dose deviation of linear accelerators in China is still lower than in developed countries. In order to ensure the therapeutic effect of the patients undergoing radiotherapy, measures should be taken to reduce the output dose deviation of linear accelerators and improve the level of qualified rate of output dose verification.

Objective To explore the feasibility of quartz glass for radiotherapy dosimetry through the experimental study of the thermoluminescence characteristics of synthetic quartz glass. Methods The thermoluminescence glow curves of quartz glass under different annealing conditions were analyzed, the thermoluminescence characteristics of quartz glass were studied, and the measurement parameters were optimized. Using the Co-60 reference radiation field in the National Secondary Standard Dosimetry Laboratory, the quartz glass samples under different annealing conditions were irradiated following the dose levels of radiotherapy, i.e., 0.5, 1.0, 2.0, 4.0, 6.0, 8.0, and 10.0 Gy, respectively. According to the relationship between the absorbed dose of quartz glass and the relative thermoluminescence signal intensity, the linearity and dispersion of the dose response of quartz glass were obtained, and the feasibility of quartz glass for radiotherapy dosimetry was analyzed. Results The linear correlation coefficient of dose response of quartz glass under annealing condition of 430℃ for 10 min was 0.9984, and the dose response dispersion was 0.97% at the absorbed dose of 2 Gy. The linear correlation coefficient of dose response of quartz glass under annealing condition of 600℃ for 1 h was 0.9911, and the dose response dispersion was 1.4% at the absorbed dose of 2 Gy. Conclusion Preliminary results suggest that quartz glass with annealing condition of 430℃ for 10 min has the potential to be used for radiotherapy dosimetry.

Objective:To preliminarily disclose the biological properties of recombinant human tau441 (P301S) protein, such as aggregation, antigenicity and immunogenicity.Methods:The recombinant plasmid tau441 (P301S) was expressed by prokaryotic expression system and purified by nickel column affinity chromatography. The protein concentrations were determined via BCA kit. The purity of protein was determined by SDS-PAGE gel coomassie brilliant blue staining. Western blot (WB) and negative staining transmission electron microscopy (TEM) were used to identify the recombinant proteins. The antigenicity was detected through indirect enzyme linked immunosorbent assay (ELISA), and the immunogenicity was detected by specific antibody titers of mouse immune serum.Results:The purity of recombinant human tau441 (P301S) was 70%. WB showed specific bands at relative molecular mass (Mr.×10 3) 64 and higher relative molecular mass. Negative staining TEM showed that tau441 (P301S) was aggregated, and the area was significantly larger than tau wild-type control protein (t=6.439, P=0.003). After 9 days of incubation at 4 ℃, tau441 (P301S) formed obvious fibrotic structure. Indirect ELISA result showed that tau441 (P301S) could be recognized by anti-tau monoclonal antibody HT7 (1∶80 000). The specific antibody titer of the immunized serum was 1∶128 000 and WB showed that the immunized serum recognized the brain lysate extract of Alzheimer’s disease (AD) transgenic mice. Conclusions:The recombinant human tau441 (P301S) protein had the characteristics of enhanced aggregation in vitro, but its antigenicity and immunogenicity were not changed.