Noise is a common occupational hazard in workplaces. Long-term exposure to high-intensity noise mainly causes occupational noise-induced hearing loss (ONIHL). The development of ONIHL is irreversible, and there is currently no cure. At present, risk assessment methods based on noise exposure intensities mainly include risk index assessment method, Engineering Professional Council assessment method in United Kingdom (EDC assessment method in UK), National Institute of Occupational Safety and Health assessment method in United State (NIOSH assessment method in US), and International Standardization Organization assessment method (ISO assessment method). However, the risk index assessment method is subjective and does not consider the effectiveness of workers wearing protective equipment. The EDC assessment method in UK defines ONIHL differently from China. The NIOSH assessment method in US and ISO assessment methods have population data sources that deviate from China, which can lead to bias in risk assessment. In the future, it is necessary to further carry out application research on the risk assessment of ONIHL in Chinese noise-exposed workers, compare the applicabilities of various assessment methods, conduct large-sample population epidemiological studies for verification, and fully utilize the risk-prediction function to prevent and control ONIHL.

Objective:To study the trinucleotide repeats of GCN (GCA, GCT, GCC, GCG) encoding Alanine in exon 3 of the PHOX2B gene among healthy individuals from southwest China and two patients with Congenital central hypoventilation syndrome (CCHS). Methods:The number and sequence of the GCN repeats of the PHOX2B gene were analyzed by capillary electrophoresis, Sanger sequencing and cloning sequencing of 518 healthy individuals and two newborns with CCHS, respectively. Results:Among the 1036 alleles of the 518 healthy individuals, five alleles were identified, including (GCN) 7, (GCN) 13, (GCN) 14, (GCN) 15 and (GCN) 20. The frequency of the (GCN) 20 allele was the highest (94.79%). And five genotypes were identified, which included (GCN) 7/(GCN) 20, (GCN) 13/(GCN) 20, (GCN) 14/(GCN) 20, (GCN) 15/(GCN) 20, (GCN) 20/(GCN) 20. The homozygous genotypes were all (GCN) 20/(GCN) 20, and the carrier rate was 89.58%. Four GCN sequences of the (GCN) 20 homozygous genotypes were identified among the 464 healthy individuals. The GCN repeat numbers in the exon 3 of the PHOX2B gene showed no significant difference between the expected and observed values, and had fulfilled the, Hardy-Weinberg equilibrium. The genotypes of the two CCHS patients were (GCN) 20/(GCN) 25 and (GCN) 20/(GCN) 30, respectively. Conclusion:It is important to determine the GCN repeats and genotypic data of the exon 3 of the PHOX2B gene among the healthy individuals. The number of GCN repeats in 518 healthy individuals was all below 20. The selection of appropriate methods can accurately detect the polyalanine repeat mutations (PARMs) of the PHOX2B gene, which is conducive to the early diagnosis, intervention and treatment of CCHS.

At present, China has not yet established a comprehensive standard and evaluation system specifically for occupational health engineering ventilation inspection. In order to meet the requirements for the design of occupational-disease-prevention facilities, the evaluation of occupational disease hazard control effectiveness, and the protective facilities, the Guangdong Provincial Occupational Health Technical Quality Control Center developed the Guangdong Province Occupational Health Engineering Ventilation Inspection Work Specification (Trial) by referring domestic and international standards and norms related to occupational health engineering, industrial ventilation design manuals and professional literature, using brainstorming and experience-based methods. The work specification covers the key detection indicators of ventilation systems, and comprehensively covers the core links of occupational health engineering ventilation testing. The relevant indicators mainly include: detection of air velocity control; wind speed and air volume of exhaust hoods and exhaust vents of ventilation facilities; detection of wind pressure, wind speed and air volume inside the ventilation duct; fresh air volume detection; and calculation and evaluation of ventilation frequency. The specification is highly practical, indicting scientific and advanced principles, and ensures the fairness and reliability of the testing process and results. Its implementation will effectively promote the standardization and professionalism of occupational health engineering ventilation testing, providing robust technical support for safeguarding workers' health.

Background The converter stations of high-voltage direct current (HVDC) transmission lines generate special total electric fields. At present, few investigations have been conducted on total electric fields in the workplace of converter stations from an perspective of occupational health. Objective To understand the current situation of total electric field strength in the workplace of converter stations. Methods Using purposive sampling, a calibrated HDEM-1 direct current (DC) total electric field strength measurement system was used to measure the total electric fields of 12 converter stations serving 6 DC lines in Southeast and Southwest China according to the Measurement method for total electric field strength and ion current density of the converter stations and DC transmission lines (DL/T 1089—2008). The results were evaluated according to occupational exposure limits recommended by The limits of electromagnetic environment at ±800 kV UHV DC converter station (DL/T 275—2012), the American Conference of Governmental Industrial Hygienists (ACGIH), and the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Results A total of 615 check points were planned, the total electric field strength was 0.05-37.05 kV·m⁻¹, and the median was 10.45 kV·m⁻¹. The total electric field strength of 39 check points (6.3%) exceeded 25 kV·m⁻¹ (the limits of ACGIH and ICNIRP), and the total electric field strength of 12 check points (2.0%) exceeded 30 kV·m⁻¹ (the limit of DL/T 275—2012). There were statistically significant differences in the total electric field strength values and the proportions of exceeding 25 kV·m⁻¹ between the neutral regions and the positive regions and between the neutral regions and the negative regions (P < 0.01). The proportion of total electric field strength exceeding 30 kV·m⁻¹ in the negative regions was higher than that in the positive regions (P < 0.01). There were no significant differences in the total electric field strength of converter stations at different voltage levels and different altitudes (P > 0.05). There were no significant differences in the proportions of total electric field exceeding 25 kV·m⁻¹ and exceeding 30 kV·m⁻¹ in converter stations at different voltage levels and different altitudes (P > 0.05). Conclusion The total electric field in some workplace of converter stations exceeds selected limits. Converter station operators may be exposed to high-strength total electric field for a short time.

Background Prolonged awkward postures during occupational activities can lead to excessive musculoskeletal load on the wrist of workers and symptoms such as wrist pain or discomfort. Objective To survey the prevalence of wrist pain among workers in 10 key industries and analyze its correlation with wrist working postures. Methods By using stratified cluster sampling method, workers from 10 key industries, such as footwear manufacturing industry, shipbuilding manufacturing industry, and automobile manufacturing industry, were selected from seven regions in North China, East China, Central China, South China, Southwest China, Northwest China, and Northeast China. The demographic information, wrist working postures, pain in wrist of the workers were collected through a cross-sectional survey. Pearson χ² test was used to compare prevalence by selected factors, trend χ² test for between group comparison, and unconditional logistic regression models for the association of wrist working postures with wrist pain. Results There were 64052 workers enrolled in this survey, and 56286 provided valid questionnaires (the effective rate was 87.8%). According to the survey, the prevalence of wrist pain was 23.3% (13112/56286), and the industries with higher prevalences were footwear manufacturing (27.1%, 1927/7106), automobile manufacturing (24.9%, 5378/21560), and shipbuilding and related equipment manufacturing (24.4%, 850/3488) industries. Finger pinching (OR=2.09, 95%CI: 1.95-2.24), frequent wrist bending (OR=2.03, 95%CI: 1.92-2.15), fixed wrist bending (OR=1.77, 95%CI: 1.69-1.85), wrist on hard edge (OR=1.34, 95%CI: 1.28-1.40), and arms over shoulders (OR=1.11, 95%CI: 1.05-1.17) increased the risk of reporting wrist pain. Conclusion Awkward postures are related to wrist pain among workers in selected 10 key industries. The related factors are wrist on hard edge, frequent wrist bending, finger pinching, fixed wrist bending, and arms over shoulders.

Sepsis is currently the leading cause of death in the intensive care unit, and its survivors also experience long-term immunosuppression and high rates of recurrent infections. At present, the clinical treatment of sepsis is still based on antibiotics, intravenous rehydration, and vasopressors, and there is no targeted drug treatment. However, as the rate of antibiotic resistance continues to increase, immunotherapy is highly anticipated as a new treatment. Patients with sepsis are often accompanied by acute leukocyte immune dysfunction and immunosuppression, which may be an important risk factor for the increasing morbidity and mortality of patients. Targeted inhibition of specific cell surface inhibitory immune checkpoint receptors and ligands, such as programmed death receptor-1 (PD-1), programmed death-ligand 1 (PD-L1), and other targets, can improve the host’s resistance to infection. In this paper, the research progress of PD-1 and PD-L1 in the immune response to sepsis was summarized to provide a theoretical basis for their further application in the treatment of sepsis in the future.

Objective To analyze the characteristics of work-related musculoskeletal disorders (WMSDs) among sonographers in Guangdong Province, and to explore the disease pattern of the cases. Methods A total of 512 sonographers from 31 hospitals in Guangdong Province were selected as the research subjects using stratified cluster sampling method. The prevalence of WMSDs in the past year was investigated using the Musculoskeletal Disorders Questionnaire, and the characteristics of WMSDs were analyzed. Latent class analysis was used to identify the disease pattern of WMSDs. Results The overall prevalence of WMSDs was 94.3%. The top five affected body parts were right shoulder, neck, right hand/wrist, lower back and right forearm/elbow, with the prevalence of 80.3%, 75.4%, 61.1%, 55.5% and 45.3%, respectively. The prevalence of WMSDs was higher on the right side for the shoulder, hand/wrist, forearm/elbow, hip/leg and knee compared with the left side (80.3% vs 31.3%, 61.1% vs 13.9%, 45.3% vs 10.0%, 17.4% vs 8.6%, 13.1% vs 8.4%, all P<0.05). The prevalence of WMSDs increased with work years, as well the prevalence of WMSDs in the top five affected body parts among the sonographers (all P<0.05). However, there were no statistical differences in prevalence of WMSDs between general hospitals and maternal and child health hospitals, tertiary hospitals and non-tertiary hospitals, Pearl River Delta hospitals and non-Pearl River Delta hospitals; there was also no statistical difference between different genders and age groups of the sonographers (all P>0.05). The best-fit latent disease pattern for sonographers WMSDs comprised three categories： symptom of neck-right shoulder, symptom of neck-lower back-right shoulder-right elbow-right hand/wrist, and symptom of multi-parts above the knees, with the latent probabilities of 0.438, 0.427 and 0.135, respectively. Conclusion The prevalence of WMSDs in sonographers is extremely high, with a dose-effect relationship with work years. The most common affected parts are neck, lower back and right shoulder, right hand/wrist, and right forearm/elbow. The prevalence of WMSDs in the right side of limb was higher than that in the left. WMSDs primarily occur in multiple parts simultaneously. The most common symptoms occur in the neck-right shoulder and neck-lower back-right shoulder-right elbow-right hand/wrist.

Objective To investigate the level of finger systolic blood pressure (FSBP) in healthy young adults. Methods A total of 28 healthy young adults were selected as the study subjects by convenient sampling method. The FSBP of the study subjects was detected at 30 and 10 ℃, and the FSBP index (F_i) was calculated. Results The FSBP of the study subjects at 30 and 10 ℃ were (102.0±16.5) and (104.4±15.2) mmHg, respectively. The FSBP in male group at 30 and 10 ℃ was (99.6±18.6) and (107.2±17.0) mmHg, respectively. The FSBP in female group at 30 and 10 ℃ was (104.4±13.9) and (101.5±2.8) mmHg, respectively. The results of factorial analysis showed that the interaction between gender and temperature on FSBP was statistically significant (P<0.05). FSBP in male group was higher at 10 than 30 ℃ (P<0.05) and higher than female group at 10 ℃ (P<0.05). There was no statistical significance for the main effect of gender, temperature, finger, or the interaction effect of gender and finger, temperature and finger for FSBP (all P>0.05). The average F_i of the study subjects was (98.0±16.6)%, with males and females having the average F_i of (100.7±20.7) % and (95.2±10.6) % respectively. The results of factorial analysis of variance showed that there was no significant difference on F_i in the main effect gender and fingers or the interaction effect between them(all P>0.05). Conclusion The FSBP test could be used as a detection method for assessing peripheral microcirculation function in Chinese population. However, further research is needed to establish reference ranges and influencing factors.

Objective: To analyze the current status of work-related musculoskeletal disorders (WMSDs), work fatigue and musculoskeletal pain in Chinese occupational population, and to study the relationship between work fatigue and musculoskeletal pain and WMSDs. Methods: A total of 66 961 employees from 323 enterprises in 15 key industries in China were selected as the study subjects using stratified cluster sampling method. The incidence of WMSDs in the past year was investigated using the Chinese version of the Musculoskeletal Disorders Questionnaire, and the work fatigue and musculoskeletal pain were investigated using Borg 6-20 Rating of Perceived Exertion Scale and visual analogue scale. The data were standardized using the age composition data of 18 to 60 years from the seventh national population census. Results: The standardized annual incidence of WMSDs was higher in the front-line workers than that in the administrative and other supportive staff (38.82% vs 36.30%). The detection rates of work fatigue and musculoskeletal pain in the study subjects were 44.54% and 63.08%, respectively. The result of S-curve fitting showed that the risk of WMSDs increased with the level of work fatigue (P<0.01). Among the front-line workers, the average of monthly fatigue frequency in the neck, shoulder, lower back, upper back, wrist/hand, foot and ankle, knee, leg, and elbow were higher in the group with WMSDs compared to those without WMSDs (all P<0.01). The pain degree of musculoskeletal pain was higher in all nine sites in the fatigued group than in the no-fatigue group (all P<0.01). The standardized detection rate of musculoskeletal pain was higher in the fatigued group than in the non-fatigued group (80.38% vs 25.71%). The work fatigue was moderate and positively correlated with musculoskeletal pain in all seven sites except the lower back and elbow, with Kendall Tau-b correlation coefficients ranging from 0.423 to 0.546 (all P<0.01). Conclusion: There is a good correlation between work fatigue and local musculoskeletal pain, work fatigue and WMSDs in Chinese occupational population. Implementing ergonomic interventions to control the development of work fatigue can be an effective measure for preventing WMSDs.

Objective: To analyze the status of noise hazard in workplace of key industries in Guangdong Province. Methods: A total of 1 061 enterprises from 14 key industries in 21 prefecture-level cities in Guangdong Province were selected as the research subjects using stratified sampling method. The occupational health survey was carried out, and the noise intensity in the workplace was detected. Results: There were 12 606 workplaces and 5 570 work sites involved among 1 061 enterprises. The median and the 0-100th percentile value ［M (P₀-P₁₀₀)］ of noise intensity in workplace were 82.6 (46.5-112.6) dB(A), and 35.03% of the workplace exceeded the national noise intensity standard. The regions and industry with the highest rate of noise exceeded the national noise intensity standard in workplace were in the northern part of Guangdong and the stone processing industry respectively. The M (P₀-P₁₀₀) of noise intensity in the work sites was 83.7 (47.5-106.2) dB(A), and 36.00% of the work sites exceeded the national noise intensity standard. The regions and industry with the highest rate of noise exceeded the national noise intensity standard in work sites were in the Pearl River Delta region and the ferrous metal mining and dressing industry respectively. The rate of noise protection facilities setting was 66.45%, and the validity of personal protection was 61.73%. The occupational medical examination was performed in 73.24% of the research subjects, and 3.25% of the result was abnormal. The industry with the highest occupational medical examination rate was nonferrous metal smelting and rolling processing, and the industry with the highest abnormal rate of occupational medical examination was stone processing industry. Conclusion: Noise hazards in workplaces of key industries in Guangdong Province are relatively severe, necessitating strengthened supervision and management, noise control measures, and efforts to reduce noise exposure levels in workplaces and work sites.