Objective To explore the wearing status and actual noise reduction effect of hearing protectors among noise workers in a typical automobile manufacturing enterprise. Methods In April 2024, an occupational hazard factor testing was carried out in an automobile manufacturing industry, and at the same time, the hearing protection fit test was conducted for noise workers. Intervention and guidance were provided to those who did not pass the minimum standard of baseline PAR. The difference in PAR between baseline and post-intervention was compared, and the effectiveness of hearing protector wearing method training was evaluated. Results The exceeding rate of the company's noise operation post was 50.77% (66/130). The baseline PAR of the subjects with working experience of less than 15 years and wearing hearing protectors throughout noisy work was higher, and the differences were statistically significant (P<0.05). Compared with those with 80dB≤L_{EX, 8h}<85dB, more research subjects with L_{EX, 8h}≥85dB failed baseline PAR (39.13%). After intervention, the PAR of the subjects who did not pass the minimum standard of baseline PRA increased from 2.0 (0.0, 5.3) to 17.0 (14.8, 20.0), and the protection level was significantly improved, and the difference was statistically significant (P<0.01). Conclusion The individual fit test of hearing protector is an important means to evaluate the actual noise reduction level of hearing protector and guide the selection of hearing protection models. Corporate training can help improve the PAR of hearing protectors.

BACKGROUND:Steroid-induced femoral head necrosis is mostly caused by long-term and extensive use of hormones,but its specific pathogenesis is not yet clear and needs further study. OBJECTIVE:To screen out the differential miRNAs in osteoclast exosomes after the intervention of Panax notoginseng saponins,and on this basis,to further construct an osteogenic-related ferroptosis regulatory network to explore the potential mechanism and research direction of steroid-induced osteonecrosis of the femoral head. METHODS:MTT assay was used to detect the toxic effects of different concentrations of dexamethasone and different mass concentrations of Panax notoginseng saponins on Raw264.7 cell line.Tartrate resistant acid phosphatase staining and TUNEL assay were used to detect the effects of Panax notoginseng saponins on osteoclast inhibition and apoptosis.Exosomes were extracted from cultured osteoclasts with Panax notoginseng saponins intervention.Exosomes from different groups were sequenced to identify differentially expressed miRNAs.CytoScape 3.9.1 was used to construct and visualize the regulatory network between differentially expressed miRNAs and mRNAs.Candidate mRNAs were screened by GO analysis and KEGG analysis.Finally,the differential genes related to ferroptosis were screened out,and the regulatory network of ferroptosis-related genes was constructed. RESULTS AND CONCLUSION:(1)The concentration of dexamethasone(0.1 μmol/L)and Panax notoginseng saponins(1 736.85 μg/mL)suitable for intervention of Raw264.7 cells was determined by MTT assay.(2)Panax notoginseng saponins had an inhibitory effect on osteoclasts and could promote their apoptosis.(3)Totally 20 differentially expressed miRNAs were identified from osteoclast-derived exosome samples,and 11 differentially expressed miRNAs related to osteogenesis were predicted by target mRNAs.The regulatory networks of 4 up-regulated differentially expressed miRNAs corresponding to 155 down-regulated candidate mRNAs and 7 down-regulated differentially expressed miRNAs corresponding to 238 up-regulated candidate mRNAs were constructed.(4)Twenty-four genes related to ferroptosis were screened out from the differential genes.Finally,12 networks were constructed(miR-98-5p/PTGS2,miR-23b-3p/PTGS2,miR-425-5p/TFRC,miR-133a-3p/TFRC,miR-185-5p/TFRC,miR-23b-3p/NFE2L2,miR-23b-3p/LAMP2,miR-98-5p/LAMP2,miR-182-5p/LAMP2,miR-182-5p/TLR4,miR-23b-3p/ZFP36,and miR-182-5p/ZFP36).These results indicate that Panax notoginseng saponins may regulate osteoblast ferroptosis by regulating the expression of miRNAs derived from osteoclast exosomes,thus providing a new idea for the study of the mechanism of steroid-induced femoral head necrosis.

Objective:To investigate the incidence of shoulder work-related musculoskeletal disorders (WMSDs) among occupational population in China, and to explore their intrinsic association with personal and work-related factors.Methods:In April 2024, 73497 valid questionnaires of the Chinese version of the Musculoskeletal Disorders Electronic Questionnaire were retrospectively analyzed from June 2018 to December 2023 in 22 provinces and 29 key industries in China, and the general information, occurrence of WMSDs and related risk factors of key occupational populations in different regions in China were collected. By using Chi-square test and confirmatory factor analysis, the relationship between shoulder fatigue and pain in key occupational groups and individual factors, work type, work posture and work organization was discussed, and the internal relationship was analyzed based on structural equation model.Results:Higher incidence of shoulder fatigue and pain were associated with female, lack of physical exercise, uncomfortable working posture and neck leaning forward ( P<0.05). Structural equation model analysis showed that work type, work posture and work organization were strongly correlated ( r=0.58, 0.55). Work organization and work type were strongly correlated with shoulder fatigue ( r=0.65) and moderately correlated with shoulder fatigue ( r=0.21). Shoulder fatigue was moderately associated with shoulder pain ( r=0.40). Individual factors, work type, work posture and shoulder fatigue could directly affect shoulder pain ( OR=0.07, -0.09, 0.17 and 0.40), and work type and work posture could also indirectly affect shoulder pain through shoulder fatigue ( OR=0.08, 0.03). Work organization only indirectly affected shoulder pain through shoulder fatigue ( OR=0.26) . Conclusion:The main influencing factor of shoulder pain is shoulder fatigue, followed by work posture and individual factors. Structural equation model can better reflect the complex relationship between work type, work posture and work organization and shoulder WMSDs. Improving work posture and work organization may be an effective way to control the influence of shoulder fatigue on shoulder pain.

Objective:To explore the structural relationship between WMSDs in the upper limbs and various risk factors in the occupational population in China, based on a large sample epidemiological survey and structural equation analysis, and to establish a structural equation model, so as to lay a foundation for the prevention and control of such diseases.Methods:The Chinese version of the Musculoskeletal Disorders Electronic Questionnaire was used to conduct a nationwide survey on the prevalence of WMSDs in the upper extremity. Six factors related to WMSDs in the upper extremity were extracted by the classification standard of adverse ergonomic factors and their source and confirmatory factor analysis, including work organization, work type, upper extremity work posture, individual factors, upper extremity fatigue and upper extremity WMSDs. The structural equation analysis was carried out and the structural equation model was established.Results:The incidence of WMSDs and fatigue in the upper limbs was 24.44% and 43.76%, respectively. The adjusted structural equation model fitting indicators were generally up to the standard (GFI=1.000, AGFI=1.000, RMSEA=0.043, NFI=0.808, TLI=0.784) . The four exogenous latent variables of work organization, work type, upper limb work posture and individual factors were correlated. There was a strong positive correlation between job type and upper limb work posture ( r=0.865) , a moderate positive correlation between work organization and job type and upper limb work posture ( r=0.570, 0.490) , and a weak negative correlation between individual factors and the other three exogenous latent variables. Upper limb work posture and individual factors had direct effects on upper limb WMSDs, and the effect coefficients were 0.10 and 0.06, respectively. Upper limb fatigue played a mediating role between work organization, work type, upper limb work posture and upper limb WMSDs. The effect coefficient was 0.46, and the composition ratios of indirect effects were 100.0%, 100.0%, and 38.3%, respectively. The direct path effect of upper limb work posture, individual factors and upper limb WMSDs was weaker than the mediating path through upper limb fatigue. Conclusion:When carrying out the prevention and control of upper limbWMSDs, it is necessary to comprehensively consider the pathogenesis path of upper limb muscle fatigue and upper limb WMSDs caused by work organization, work type, and upper limb work posture, so as to provide theoretical reference for improving the prevention and control level of such diseases.

Cervical spinal cord injury without fracture-dislocation (CSCIWFD) is referred to as a special type of cervical spinal cord injury characterized by traumatic spinal cord dysfunction and no significant bony structural abnormalities on imagines. Duo to the high risk of missed diagnosis during the initial consultation, CSCIWFD may lead to progressive neurological deterioration or even complete paralysis, severely impacting patients′ prognosis. Currently, there are no established consensuses over the diagnosis and treatment of CSCIWFD, such as the lack of evidence-based standards for indications of non-surgical treatment and risk of secondary neurological injury, as well as debates over the optimal timing for surgical intervention and indications for different surgical approaches. To address these issues, the Spine Trauma Group of the Orthopedic Branch of the Chinese Medical Doctor Association organized experts in the relevant fields to formulate Diagnosis and treatment guideline for acute cervical spinal cord injury without fracture- dislocation in adults ( version 2025) . Based on evidence-based medicine and the principles of scientific rigor and clinical applicability, the guidelines proposed 11 recommendations covering terminology, diagnosis, evaluation treatment, and rehabilitation, etc., aiming to standardize the management of CSCIWFD.

Vertebral refracture following percutaneous vertebral augmentation (PVA) is commonly seen in elderly patients with osteoporotic thoracolumbar compression fractures (OTLCF). It can lead to recurrent pain, loss of vertebral height, progression of kyphosis, and even neurological dysfunction, significantly impairing patients′ quality of life. Current diagnosis and treatment face multiple challenges, including high misdiagnosis rate, difficulty in choosing between surgical and non-surgical treatment options, lack of standardized surgical protocols, interference from intralesional bone cement during procedures, inadequate stability of internal fixation in osteoporotic bone, and suboptimal compliance of anti-osteoporotic therapy. Establishing a standardized diagnostic and therapeutic framework is urgently needed. To standardize the management process and improve outcomes for vertebral refractures after PVA in elderly OTLCF patients, Spinal Trauma Group of the Orthopedic Branch of Chinese Medical Doctor Association organized experts in the field to develop Guideline for the diagnosis and treatment of vertebral refracture after percutaneous vertebral augmentation in elderly patients with osteoporotic thoracolumbar compression fractures ( version 2025), based on current literature and clinical experience, and adhering to principles of scientific rigor and clinical applicability. A total of 11 recommendations were proposed, encompassing diagnosis, treatment, and rehabilitation of vertebral refracture after PVA in elderly patients with OTLCF, aiming to provide a foundation for a standardized management.

Objective: To explore the alleviating effect of geniposide on ulcerative colitis (UC) and to investigate its potential mechanism. Methods: A UC mouse model was induced using 5% dextran sulfate sodium ( DSS) . These mice were randomly divided into 6 groups ( n = 8) : control group , model group , sulfasalazine group[ 100 mg/(kg ·d) ] , low-dose geniposide group[ 10 mg/(kg ·d) ] , medium-dose geniposide group[20 mg/(kg ·d) ] , and high-dose geniposide group[40 mg/( kg · d) ] . The mice were orally administered for consecutive 10 days . The colon length and mouse body mass were measured , and the colon mucosal damage index (CMDI) and disease activity index (DAI) were scored . The pathological changes in colon tissue were observed using hematoxylin-eosin (HE) staining. The reagent kits were used to measure the levels of malondialdehyde ( MDA) , myeloperoxidase (MPO) , catalase ( CAT) , and glutathione ( GSH) in colon tissue . The enzyme linked immunosorbent assay (ELISA) was used to analyze the expression levels of tumor necrosis factor-α ( TNF-α) , interleukin-6 ( IL-6) , and IL-1βin colon tissue . Western blot was used to detect the protein expression of mucin 1 (MUC-1) , occludin , IL-6 , p-JAK2 , and p-STAT3 in colon tissue . Results: Compared with the normal control group , the body mass and colon length of the model group mice significantly reduced . The expression of MUC-1 and occludin proteins sig- nificantly reduced (P < 0. 01) . The activities of CAT and SOD significantly reduced . DAI score and CMDI score significantly increased (P < 0. 01) . The expression levels of TNF-α, IL-6 , and IL-1βsignificantly increased (P < 0. 01) . The content of MPO and MDA significantly increased (P < 0. 01) . The expression of IL-6 , p-JAK2 and p- STAT3 proteins significantly increased ( P < 0. 01) . Compared with the model group , the body mass and colon length of mice in sulfasalazine group and geniposide medium and high-dose groups significantly increased (P < 0. 05 or P < 0. 01) , the expression of MUC-1 and occludin proteins increased (P < 0. 05 or P < 0. 01) , as well as the activity of CAT and SOD (P < 0. 05 or P < 0. 01) . DAI score and CMDI score in Sulfasalazine group and genipo- side medium and high-dose groups significantly reduced (P < 0. 05 or P < 0. 01) , as well as the expression levels of TNF-α, IL-6 , and IL-1β(P < 0. 05 or P < 0. 01) . MPO and MDA content in Sulfasalazine group and genipo- side medium and high-dose groups significantly reduced (P < 0. 05 or P < 0. 01) , as well as the expression of IL- 6 , p-JAK2 , and p-STAT3 proteins (P < 0. 05 or P < 0. 01) . Conclusion Geniposide maintaines intestinal home- ostasis by regulating the structure of the intestinal flora and improves colitis injury in UC mice by inhibiting the acti- vation of the IL-6/JAK2/STAT3 pathway.

Objective:To explore the effects of early electroacupuncture(EA)intervention on the high mobility group box 1(HMGB1)/Toll-like receptor 4(TLR4)signaling pathway-related protein expression and oligodendrocytes in mice with amyotrophic lateral sclerosis(ALS),and uncover the potential molecular mechanisms underlying the improvement of motor function in ALS mice by early EA intervention.Methods:ALS mice carrying the SOD1G93A gene were randomly divided into a model group and an EA group,with 10 mice in each group;10 littermate mice with a negative SOD1G93A genotype served as the control group.In the EA group,Baihui(GV20),Tianzhu(BL10),and Tianshu(ST25)were selected with needles retained for 10 min,5 consecutive days per week,with 2 days of rest.One week constituted a course of treatment,and a total of 3 consecutive courses were performed.The other groups were grasped and fixed similarly,but without intervention.Motor function was assessed using the open field test(OFT)and Morris water maze(MWM).Subsequently,hematoxylin-eosin staining was used to observe neuron morphology in the M1 region of the cerebral cortex.Immunofluorescence was performed to detect the positive cell rate of TAR DNA-binding protein 43(TDP-43),and double immunofluorescence staining was used to observe the positive cell rate and cell states of ionized calcium-binding adaptor molecule 1(Iba-1)and myelin basic protein(MBP)in the M1 region of the cerebral cortex.Western blotting was used to detect the relative expression levels of TDP-43,tumor necrosis factor(TNF)-α,HMGB1,and TLR4 proteins.Results:Compared to the control group,the model group exhibited a reduced total movement distance in the OFT,and an increased escape latency,as well as fewer platform crossings in the MWM,with statistically significant differences(P<0.01).In the model group,the number of degenerated and necrotic neurons in the M1 region of the ALS mouse cerebral cortex increased,with significant nuclear shrinkage and cytoplasmic vacuolization;the percentage of TDP-43 immunofluorescence positive cells in the M1 region of the cerebral cortex increased(P<0.01),and the relative expression level of TDP-43 protein in the cerebral cortex showed a significant increase(P<0.01);the Iba-1 positive cell percentage increased,while the MBP positive cell percentage decreased(P<0.01);the relative expression levels of TNF-α,HMGB1,and TLR4 proteins increased(P<0.05).Compared to the model group,the EA group showed an increased total movement distance(P<0.01),and a reduced escape latency,and more platform crossings in the MWM,with statistically significant differences(P<0.05).In the EA group,neurons showed improvement,with reduced degeneration and necrosis,and larger,clearer nuclei;the percentage of TDP-43 immunofluorescence positive cells in the M1 region of the cerebral cortex decreased(P<0.05),and the relative expression level of TDP-43 protein also decreased(P<0.05);the percentage of Iba-1 positive cells in the M1 region of the cerebral cortex decreased,while the percentage of MBP positive cells increased(P<0.01);the relative expression levels of TNF-α,HMGB1,and TLR4 proteins decreased(P<0.05).Conclusion:EA intervention can suppress microglial activation,improve the state of oligodendrocytes,and reduce abnormal TDP-43 aggregation in the M1 region of the cerebral cortex in ALS model mice;its mechanism of action may be related to the HMGB1/TLR4 signaling pathway.

The discovery of hemoglobin variants with low oxygen affinity,diagnostic methods,prognosis of carriers,and developments in analyzing hemoglobin oxygen-carrying and-releasing abilities are reviewed in this article in order to draw the attention of related clinical departments and to provide references for optimizing the process of diagnosis and treatment.Hemoglobin variants with low oxygen affinity originate from gene mutations encoding hemoglobin and autosomal dominant inheritance.The diagnosis should be combined with clinical manifestations and family history and differentiated from methemoglobinemia.A decrease in pulse oxygen saturation(SpO2)is often the first abnormality observed in asymptomatic carriers of hemoglobin variants with low oxygen affinity.Laboratory examinations include arterial blood gas analysis,hemoglobin oxygen affinity testing,protein analysis and gene sequencing.Most carriers do not require specific treatment and have a good prognosis,who should avoid acute hypoxic injuries induced by strenuous exercise,emotional stress,or high temperature.Moreover,health practitioners should pay attention to their responses to anesthetics,agents that induce oxidative stress,drugs that increase hemoglobin oxygen affinity,and prostacyclins.Hemoglobin oxygen-carrying and-releasing analysis is a promising tool to identify carriers of hemoglobin variants with low oxygen affinity because it does not involve unnecessary or invasive examinations and is of significant values for clinical diagnosis and treatment.

Objective:To examine the association between bilateral 4000 Hz hearing loss and blood pressure abnormalities, providing a scientific basis for occupational health management and interventions for noise-induced hearing loss.Methods:In October 2024, 23100 noise-exposed workers who underwent occupational health examinations at Tianjin Institute of Occupational Disease Prevention and Treatment from January 2023 to December 2023 were selected as study subjects. Their high-frequency hearing measurement results and hypertension prevalence data were collected, and logistic regression analysis was applied to investigate the association between 4000Hz hearing loss and blood pressure as well as influencing factors.Results:Among 23100 noise-exposed workers, hypertension was observed in 16.62% (3840/23100), high-frequency hearing loss in 30.49% (7043/23100). Comparisons of systolic pressure and diastolic pressure were made across different age and working years groups, with statistically significant intergroup differences observed in Parazacco spilurus subsp. spilurus (systolic pressure F=183.39, P<0.001; diastolic pressure F=195.61, P<0.001; systolic pressure F=107.26, P<0.001; diastolic pressure F=111.19, P<0.001). Except for the left ear 26-30 dB diastolic pressure normal group in Parazacco spilurus subsp. spilurus, the OR values of systolic pressure and diastolic pressure in other groups were all >1, showing statistically significant differences ( P<0.05). Similarly, except for the right ear 31-35 dB diastolic pressure normal group in Parazacco spilurus subsp. spilurus, the OR values of systolic pressure and diastolic pressure in other groups were all >1, with statistically significant differences ( P<0.05). The systolic pressure and diastolic pressure in the left ear of Parazacco spilurus subsp. spilurus increased with the degree of hearing loss ( χ2trend=126.60, 68.80, P<0.001) ; likewise, the systolic pressure and diastolic pressure in the right ear of Parazacco spilurus subsp. spilurus also increased with the degree of hearing loss ( χ2trend=119.02, 54.50, P<0.001) . Conclusion:4000 Hz hearing loss exhibits a dose-response relationship with abnormal blood pressure. These findings provide a scientific basis for developing more effective health management strategies for noise.