Background 900 MHz radiofrequency radiation (RF) is a commonly used frequency in modern wireless communication devices, and its potential health effects have drawn much attention, especially its impact on bone metabolism, which has not been fully clarified. Objective To investigate the effects of 900 MHz RF on the bone tissue and osteoblast senescence of mice, as well as the dose-effect relationship. Methods In vivo, 3-month-old female C57BL/6 mice were divided into five groups (n=10): sham exposure, low-dose RF (50 μW·cm⁻²), medium-dose RF (150 μW·cm⁻²), high-dose RF (450 μW·cm⁻²), and D-galactose positive control (D-gal). Treatments were administered for 4 h per day for 28 d. Bone mineral density (BMD) and microstructure, including bone volume (BV), tissue volume (TV), bone volume fraction (BV/TV), trabecular number (Tb.N), trabecular separation (Tb.Sp), and trabecular thickness (Tb.Th), were assessed by Micro-CT; bone morphology was examined after hematoxylin and eosin (HE) staining; osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-κΒ ligand (RANKL) expression was detected by immunohistochemistry; serum OPG, tartrate-resistant acid phosphatase 5b (TRACP-5b), plasminogen activator inhibitor-1 (PAI-1), interleukin-6 (IL-6), and C-X-C motif chemokine ligand 15 (CXCL15) levels were measured by enzyme-linked immunosorbent assay (ELISA); mRNA expression of Tp53, Cdkn1a, and Cdkn2a in bone tissue was analyzed by reverse transcription polymerase chain reaction (RT-PCR). In vitro, MC3T3-E1 pre-osteoblasts were grouped into sham, low-dose RF (50 μW·cm⁻²), medium-dose RF (150 μW·cm⁻²), high-dose RF (450 μW·cm⁻²), and H₂O₂ control, groups, and were exposed for 4 h per day for 5 d. Cell morphology was observed by microscopy; viability was tested by cell counting kit-8 (CCK-8); senescence was evaluated by senescence-associated β-galactosidase (SA-β-gal) staining; P53 and P21 protein expression was detected by Western blot; Tp53 and Cdkn1a mRNA levels were measured by RT-PCR. Results In vivo, RF at each dose significantly reduced the BMD of the mice's femurs and the bone microstructure parameters, such as BV/TV, Tb.N, and Tb.Th (P<0.05). Among them, Tb.Sp only increased in the 150 μW·cm⁻² RF group (P<0.05), with a looser bone network; fewer, sparser trabeculae and increased marrow fat were observed after HE staining; down-regulated OPG and up-regulated RANKL expression levels were observed by immunohistochemistry; the ELISA test revealed that the serum OPG levels in the 150 μW·cm⁻² RF group and the 450 μW·cm⁻² RF group of mice were significantly decreased (P<0.05), while the indicator in the 50 μW·cm⁻² RF group showed a decreasing trend but the difference was not statistically significant (P>0.05), TRACP-5b rose, and PAI-1, IL-6, and CXCL15 levels increased (P<0.05); the RT-PCR results showed thatTp53, Cdkn1a, and Cdkn2a mRNA expression was upregulated (P<0.05). In vitro, radiofrequency radiation induced cell flattening, reduced viability (P<0.05), increased SA-β-gal-positive cells (P<0.05), and upregulated P53, P21, Tp53, and Cdkn1a expression (P<0.05). Conclusion 900 MHz RF disrupts bone metabolism in mice by inhibiting bone formation, promoting resorption, and inducing osteoblast senescence, accelerating bone aging. The 150 μW·cm⁻² RF dose exhibits the most pronounced effect, reflecting a nonlinear “window effect,” highlighting potential health risks.

Background Kurtosis reflecting noise's temporal structure is an effective metric for evaluating noise-induced hearing loss (NIHL), and its threshold is still unclear. Objective To explore the energy range of kurtosis and the threshold of NIHL induced by kurtosis in this energy rangeMethods Using cross-sectional design, 4631 noise-exposed workers in manufacturing industry were selected. The hearing loss and noise exposure data of each worker were collected. Logistic regression model was used to establish the dose-response relationship between noise exposure and hearing loss and estimate the range of energy effects. Restricted cubic spline model was utilized to analyze the dose-response relationship curves of kurtosis to noise-induced hearing loss (NIHI) and high-frequency noise-induced hearing loss (HFNIHL) under different 8 h equivalent sound levels (L_{EX,8 h}), as well as to estimate the kurtosis effect threshold. Results The logistic regression model analysis showed that the prevalence of NIHI and HFNIHL increased significantly with increase of L_{EX,8 h} for steady noise; when L_{EX,8 h} of non-steady noise was 80-100 dB(A), the risk of hearing loss increased with an increase in kurtosis (P<0.05). The restricted cubic spline model showed that when L_{EX,8 h} of non-steady noise was 0-80 dB(A) or >100 dB(A), there was no significant relationship between kurtosis and NIHI or HFNIHL. When L_{EX,8 h} was 80-100 dB(A), there was a significant nonlinear dose-response relationship between kurtosis and NIHL or HFNIHL (P <0.001), and kurtosis > 28.08 exerted effect in elevating NIHI or HFNIHL. Conclusion The effect threshold of kurtosis on NIHL is 28.08 when non-steady noise levels are in the range of 80-100 dB(A). The effect threshold of kurtosis needs further verification.

Background Temporal kurtosis (without frequency weighting, i.e., Z-weighted kurtosis) can evaluate noise-induced hearing loss (NIHL). However, few studies have considered the function of frequency weighting (A- or C-weighted) kurtosis on NIHL. Objective To study the significance of A- and C-weighted kurtosis adjustment for equivalent sound level (L'_{EX,8 h}) in evaluating occupational hearing loss. Methods A cross-sectional survey was used to select 973 noise-exposed workers in seven industries as the subjects. The noise exposure of all workers was assessed by distributions of A-, C-, and Z-weighted kurtosis (e.g., K_A, K_C, and K_Z) and respective adjusted equivalent sound level (e.g., L'_{EX,8 h}-K_A, L'_{EX,8 h}-K_C, and L'_{EX,8 h}-K_Z). The significance of A- and C-weighted kurtosis in evaluating NIHL was evaluated by correlations between three types of L'_{EX,8 h} and NIHL, and improvement of noise-induced permanent threshold shift (NIPTS) underestimation predicted by the ISO prediction model (Acoustics—Estimation of noise-induced hearing loss, ISO 1999-2013). Results The median K_A, K_C, and K_Z were 68.33, 28.22, and 19.82, respectively. The binary logistic regression showed that L_{EX, 8 h}-K_A, L_{EX, 8 h}-K_C, and L'_{EX, 8 h}-K_Z were risk factors for NIHL (OR>1, P<0.001). The receiver operating characteristic (ROC) curve showed that when the outcome variable was noise-induced hearing impairment (NIHI), the areas under the curves corresponding to L'_{EX,8 h}-K_A, L'_{EX,8 h}-K_C, and L'_{EX,8 h}-K_Z were 0.625, 0.628, and 0.625, respectively. When the outcome variable was high-frequency noise-induced hearing loss (HFNIHL), the areas under the curves corresponding to L'_{EX,8 h}-K_A, L'_{EX, 8 h}-K_C, and L'_{EX,8 h}-K_Z were 0.624, 0.623, and 0.622, respectively (P<0.05). The order of underestimation improvement values predicted by L'_{EX,8 h} for NIPTS₁₂₃₄ was: L'_{EX,8 h}-K_A (4.68 dB HL)>L'_{EX,8 h}-K_C (4.38 dB HL)>L'_{EX,8 h}-K_Z (4.28 dB HL) (P<0.001). The order of underestimation improvement values predicted by L'_{EX,8 h}-K for NIPTS₃₄₆ was: L'_{EX,8 h}-K_A (7.20 dB HL)>L'_{EX,8 h}-K_C (6.83 dB HL)>L'_{EX,8 h}-K_Z (6.71 dB HL) (P<0.001). Conclusion The adjustment of A- and C-weighted kurtosis to equivalent sound level L_{EX,8 h} can effectively improve the accuracy of the ISO 1999 prediction model in NIPTS prediction, and compared with the C-weighted, the A-weighted kurtosis can improve the result of the ISO 1999 prediction model in terms of underestimating NIPTS.

background Current assessment of noise-induced hearing loss relies on the hearing threshold statistical distribution table of ISO 7029-2017 standard (ISO 7029), which is based on foreign population data and lacks a hearing threshold distribution table derived from pure-tone audiometry data of the Chinese population, hindering accurate evaluation of hearing loss in this group. Objective To establish a statistical distribution table of hearing threshold level (HTL) for otologically normal Chinese adults and to provide a scientific basis for revising the diagnostic criteria of occupational noise-induced deafness in China. Methods A total of 1271 otologically normal Chinese adults aged 18-60 years were divided into four groups with 10-year age intervals. Based on the pure tone audiometry data and power function operation formula, the relevant parameters of the median and percentile calculation formula of ISO 7029 were adjusted. Based on the adjusted parameters, a statistical distribution table of HTL of normal Chinese adults in otology was preliminarily constructed according to the calculation formula of ISO 7029. A nonparametric rank sum test was used to compare the difference between the adjusted median deviation value and the ISO 7029 calculation. Results Except for a few frequencies (2000, 3000, and 8000 Hz), the value of parameter α adjusted for the auditory threshold deviation of the Chinese population (α_CHN-md) increased with the increase of frequency, while the value of parameter β adjusted for the auditory threshold deviation of the Chinese population (β_CHN-md) decreased with the increase of frequency. The preliminary distribution table of otologically normal Chinese adults' median hearing threshold deviation (ΔH_CHN-md) showed that the hearing threshold deviation increased with age and frequency. At 8000 Hz, the increase in ΔH_CHN-md with age was the greatest for both men and women, from 0 dB to 23 dB and 21 dB respectively. The minimal threshold elevation was noted at 500, 1000, and 2000 Hz, which increased from 0 dB to 2 dB. In otologically normal Chinese adults, the maximum increase of ΔH_CHN-md with frequency was observed at age of 50 years, which increased from 2 dB at 500 Hz to 23 dB at 8000 Hz in men and from 2 dB at 500 Hz to 21 dB at 8000 Hz in women. The comparison results with the ISO 7029 calculation showed that the trend was consistent. The median hearing threshold deviation value of the adjusted Chinese population was lower than that of the ISO 7029 calculation (ΔH_md). However, they had no significant statistical difference (P>0.05). For otologically normal normal Chinese men and women, the maximum difference of ΔH_md between the 50-year-old group and the ISO calculation at 8000 Hz was 7 dB and 9 dB, respectively. Conclusion This preliminary analysis of hearing threshold deviations in otologically normal Chinese adults suggests that current standards may potentially underestimate hearing loss at frequencies below 8000 Hz while possibly overestimating it at 8000 Hz. These findings require further validation through expanded sample sizes to more accurately assess the characteristics of hearing thresholds in the Chinese population and their discrepancies with existing standards.

Coronavirus disease 2019 (COVID-19) is a multi-system disease that can lead to various severe complications. Acute limb ischemia (ALI) has been increasingly recognized as a COVID-19-associated complication that often predicts a poor prognosis. However, the pathophysiology and molecular mechanisms underlying COVID-19-associated ALI remain poorly understood. Hypercoagulability and thrombosis are considered important mechanisms, but we also emphasize the roles of vasospasm, hypoxia, and acidosis in the pathogenesis of the disease. The angiotensin-converting enzyme 2 (ACE2) pathway, inflammation, and platelet activation may be important molecular mechanisms underlying these pathological changes induced by COVID-19. Furthermore, we discuss the hypotheses of risk factors for COVID-19-associated ALI from genetic, age, and gender perspectives based on our analysis of molecular mechanisms. Additionally, we summarize therapeutic approaches such as use of the interleukin-6 (IL-6) blocker tocilizumab, calcium channel blockers, and angiotensin-converting enzyme inhibitors, providing insights for the future treatment of coronavirus-associated limb ischemic diseases.
Humans ; COVID-19/physiopathology* ; Ischemia/etiology* ; SARS-CoV-2 ; Extremities/blood supply* ; Risk Factors ; Interleukin-6/antagonists & inhibitors* ; Acute Disease ; Angiotensin-Converting Enzyme 2

Although cisplatin is a widely used chemotherapeutic agent, it is severely toxic and causes irreversible hearing loss, restricting its application in clinical settings. This study aimed to determine the molecular mechanism underlying cisplatin-induced ototoxicity. Here, we established in vitro and in vivo ototoxicity models of cisplatin-induced hair cell loss, and our results showed that reducing STING levels decreased inflammatory factor expression and hair cell death. In addition, we found that cisplatin-induced mitochondrial dysfunction was accompanied by cytosolic DNA, which may act as a critical linker between the cyclic GMP-AMP synthesis-stimulator of interferon genes (cGAS-STING) pathway and the pathogenesis of cisplatin-induced hearing loss. H-151, a specific inhibitor of STING, reduced hair cell damage and ameliorated the hearing loss caused by cisplatin in vivo. This study underscores the role of cGAS-STING in cisplatin ototoxicity and presents H-151 as a promising therapeutic for hearing loss.
Cisplatin/toxicity* ; Animals ; Nucleotidyltransferases/antagonists & inhibitors* ; Membrane Proteins/antagonists & inhibitors* ; Signal Transduction/drug effects* ; Mice ; Hair Cells, Auditory, Inner/pathology* ; Antineoplastic Agents/toxicity* ; Mice, Inbred C57BL ; Hearing Loss/metabolism* ; Male ; Ototoxicity/metabolism*

ObjectiveBased on the concept of quality by design（QbD）， the processing process of calcined Pyritum was optimized， and its X-ray diffraction（XRD） fingerprint was established. MethodsThe safety， effectiveness and quality controllability of calcined Pyritum were taken as the quality profile（QTPP）， the color， hardness， metallic luster， phase composition， the contents of heavy metals and hazardous elements were taken as the critical quality attributes（CQAs）， and the calcination temperature， calcination time， paving thickness and particle size were determined as the critical process parameters（CPPs）. Differential thermal analysis， X-ray diffraction（XRD） and inductively coupled plasma mass spectrometry（ICP-MS） were used to analyze the correlation between the calcination temperature and CQAs of calcined Pyritum. Then， based on the criteria importance through intercriteria correlation（CRITIC）-entropy weight method， the optimal processing process of calcined Pyritum was optimized by orthogonal test. Powder XRD was used to analyze the phase of calcined Pyritum samples processed according to the best process， and the mean and median maps of calcined Pyritum were established by the superposition of geometric topological figures， and similarity evaluation and cluster analysis were carried out. ResultsThe results of single factor experiments showed that the physical phase of Pyritum changed from FeS₂ to Fe₇S₈ during the process of temperature increase， the color gradually deepened from dark yellow， and the contents of heavy metals and harmful elements decreased. The optimized processing process of calcined Pyritum was as follows：calcination temperature at 750 ℃， calcination time of 2.5 h， paving thickness of 3 cm， particle size of 0.8-1.2 cm， vinegar quenching 1 time［Pyritum-vinegar（10∶3）］. After calcination， the internal structure of Pyritum was honeycomb-shaped， which was conducive to the dissolution of active ingredients. XRD fingerprints of 13 batches of calcined Pyritum characterized by 10 common peaks were established. The similarities of the relative peak intensities of the XRD fingerprints of the analyzed samples were>0.96， and it could effectively distinguish the raw products and unqualified products. ConclusionTemperature is the main factor affecting the quality of calcined Pyritum. After processing， the dissolution of the effective components in Pyritum increases， and the contents of heavy metals and harmful substances decrease， reflecting the function of processing to increase efficiency and reduce toxicity. The optimized processing process is stable and feasible， and the established XRD fingerprint can be used as one of the quality control standards of calcined Pyritum.

ObjectiveBased on the concept of quality by design（QbD）， the processing process of calcined Pyritum was optimized， and its X-ray diffraction（XRD） fingerprint was established. MethodsThe safety， effectiveness and quality controllability of calcined Pyritum were taken as the quality profile（QTPP）， the color， hardness， metallic luster， phase composition， the contents of heavy metals and hazardous elements were taken as the critical quality attributes（CQAs）， and the calcination temperature， calcination time， paving thickness and particle size were determined as the critical process parameters（CPPs）. Differential thermal analysis， X-ray diffraction（XRD） and inductively coupled plasma mass spectrometry（ICP-MS） were used to analyze the correlation between the calcination temperature and CQAs of calcined Pyritum. Then， based on the criteria importance through intercriteria correlation（CRITIC）-entropy weight method， the optimal processing process of calcined Pyritum was optimized by orthogonal test. Powder XRD was used to analyze the phase of calcined Pyritum samples processed according to the best process， and the mean and median maps of calcined Pyritum were established by the superposition of geometric topological figures， and similarity evaluation and cluster analysis were carried out. ResultsThe results of single factor experiments showed that the physical phase of Pyritum changed from FeS₂ to Fe₇S₈ during the process of temperature increase， the color gradually deepened from dark yellow， and the contents of heavy metals and harmful elements decreased. The optimized processing process of calcined Pyritum was as follows：calcination temperature at 750 ℃， calcination time of 2.5 h， paving thickness of 3 cm， particle size of 0.8-1.2 cm， vinegar quenching 1 time［Pyritum-vinegar（10∶3）］. After calcination， the internal structure of Pyritum was honeycomb-shaped， which was conducive to the dissolution of active ingredients. XRD fingerprints of 13 batches of calcined Pyritum characterized by 10 common peaks were established. The similarities of the relative peak intensities of the XRD fingerprints of the analyzed samples were>0.96， and it could effectively distinguish the raw products and unqualified products. ConclusionTemperature is the main factor affecting the quality of calcined Pyritum. After processing， the dissolution of the effective components in Pyritum increases， and the contents of heavy metals and harmful substances decrease， reflecting the function of processing to increase efficiency and reduce toxicity. The optimized processing process is stable and feasible， and the established XRD fingerprint can be used as one of the quality control standards of calcined Pyritum.

Objective:To explore the relationship between autistic trait and pain empathy among college students, as well as the mediating role of personal pain perception.Methods:From October to December 2023, a cross-sectional survey was conducted among 1 195 college students using the autism spectrum quotient, pain sensitivity questionnaire, fear of pain questionnaire, pain catastrophizing scale and empathy for pain scale.SPSS 27.0 software was used for descriptive statistics and correlation analysis.A structural equation model was constructed using Mplus 8.3 to examine the mediating effect of personal pain perception, which was composed of pain sensitivity, fear and catastrophizing cognition.Results:Autistic trait(22.00(18.00, 26.00))was significantly positively correlated with pain sensitivity (55.00(43.00, 70.00)), fair of pain (69.00(60.00, 78.00)), and pain catastrophizing cognition (16.00(8.00, 23.00)) ( r=0.112, 0.154, 0.204, all P<0.001).Autistic trait was also significantly positively correlated with affective distress(62.00(46.00, 80.00), r=0.162, P<0.001) and vicarious pain (14.00(8.00, 20.00), r=0.096, P<0.001) of pain empathy.Pain sensitivity, fear of pain and pain catastrophizing cognition were significantly positively correlated with affective distress( r=0.244, 0.332, 0.375, all P<0.001) and vicarious pain ( r=0.210, 0.232, 0.285, all P<0.001) of pain empathy.The effects of autistic trait on affective distress and vicarious pain dimensions of pain empathy were fully mediated by personal pain perception, with the mediating effects of 0.115( P<0.001, 95% CI=0.073-0.165) and 0.085( P<0.001, 95% CI=0.053-0.124). Conclusions:The autistic trait of college students can predict the affective distress and vicarious pain of pain empathy indirectly through personal pain perception.

Objective:To explore the relationship between autistic trait and pain empathy among college students, as well as the mediating role of personal pain perception.Methods:From October to December 2023, a cross-sectional survey was conducted among 1 195 college students using the autism spectrum quotient, pain sensitivity questionnaire, fear of pain questionnaire, pain catastrophizing scale and empathy for pain scale.SPSS 27.0 software was used for descriptive statistics and correlation analysis.A structural equation model was constructed using Mplus 8.3 to examine the mediating effect of personal pain perception, which was composed of pain sensitivity, fear and catastrophizing cognition.Results:Autistic trait(22.00(18.00, 26.00))was significantly positively correlated with pain sensitivity (55.00(43.00, 70.00)), fair of pain (69.00(60.00, 78.00)), and pain catastrophizing cognition (16.00(8.00, 23.00)) ( r=0.112, 0.154, 0.204, all P<0.001).Autistic trait was also significantly positively correlated with affective distress(62.00(46.00, 80.00), r=0.162, P<0.001) and vicarious pain (14.00(8.00, 20.00), r=0.096, P<0.001) of pain empathy.Pain sensitivity, fear of pain and pain catastrophizing cognition were significantly positively correlated with affective distress( r=0.244, 0.332, 0.375, all P<0.001) and vicarious pain ( r=0.210, 0.232, 0.285, all P<0.001) of pain empathy.The effects of autistic trait on affective distress and vicarious pain dimensions of pain empathy were fully mediated by personal pain perception, with the mediating effects of 0.115( P<0.001, 95% CI=0.073-0.165) and 0.085( P<0.001, 95% CI=0.053-0.124). Conclusions:The autistic trait of college students can predict the affective distress and vicarious pain of pain empathy indirectly through personal pain perception.