Background Long working hours are a risk factor for occupational health, particularly in labor-intensive sectors such as manufacturing. Prolonged working hours may have adverse effects on the sleep and mental health of employees. Objective To investigate the impact of long working hours on insomnia, anxiety, and depression symptoms among manufacturing industry employees and provide scientific evidence for relevant occupational health interventions. Methods A cross-sectional study was conducted involving 1524 employees from eight manufacturing enterprises in Shenzhen. Data were collected using a structured questionnaire, which included demographic characteristics, work conditions (e.g., years of employment, job type, shift work, night shifts, weekly working hours), personal behaviors (e.g., smoking and drinking habits), and the occurrence of insomnia (by the Athens Insomnia Scale), anxiety (by the Generalized Anxiety Disorder Scale), and depression (by the Patient Health Questionnaire). Participants were classified into two groups based on working hours: long working hours (≥55 h per week) and normal working hours (35-40 h per week). Binary logistic regression was used to analyze the association between long working hours and the occurrences of insomnia, anxiety, and depression symptoms. Results A total of 1491 manufacturing industry employees were included in the study (response rate: 97.8%). The sample consisted of 54.19% males and 45.81% females, with the largest proportion was those aged 40-49 years (45.48%). The proportion of workers with long working hours in the total population was 31.52%, with the highest proportion among production and technical employees (36.49%). The prevalence of insomnia, anxiety, and depression symptoms was 56.2%, 26.6%, and 23.8%, respectively in the long working hours group, significantly higher than those in the normal working hours group (P<0.05). After adjusting for potential confounders, the logistic regression analysis showed that long working hours were significantly associated with increased risks of insomnia (OR=2.16, 95%CI: 1.60, 2.91), anxiety (OR=1.94, 95%CI: 1.34, 2.81), and depression symptoms (OR=1.62, 95%CI: 1.11, 2.38) compared to normal working hours. Conclusion Long working hours significantly increase the risks of insomnia, anxiety, and depression symptoms among manufacturing industry employees. It is recommended that measures should be implemented to limit working hours, increase rest periods, and provide occupational health education and psychological support to improve the sleep and mental health of employees.

Objective To assess the impact of long working hours on sleep disorders among manufacturing workers and explore the roles of alcohol consumption and mental health factors(anxiety and depressive symptoms)in this association.Methods A cross-sectional study design was used to survey 1 336 manufacturing workers in Shenzhen.We collected the data of their demographic characteristics,work-related factors,personal behaviors,sleep disorders,and mental health status.Multivariate Logistic regression analysis was used to assess the association between long working hours and sleep disorders.Stratified analysis and mediation effect models were applied to examine the effect modification by alcohol consumption and the mediating role of mental health factors,respectively.Results Among the study samples,31.8％reported long working hours and 45.6％had sleep disorders.Multivariate Logistic regression analysis showed that long working hours significantly increased the risk of sleep disorders(adjusted OR=2.073,95％ CI:1.478-2.907,P＜0.001).Stratified analysis revealed that the association between long working hours and sleep disorders was more pronounced among alcohol consumers(adjusted OR=2.556,95％ CI:1.432-4.562,P=0.001).Mediation effect analysis showed that anxiety and depressive symptoms partially mediated the relationship between long working hours and sleep disorders,with indirect effects accounting for 25.71％ and 27.14％,respectively.Conclusion Long working hours increase the risk of sleep disorders among manufacturing workers,particularly among those who consume alcohol.Anxiety and depressive symptoms partially explain the association between long working hours and sleep disorders.

Objective To assess the impact of long working hours on sleep disorders among manufacturing workers and explore the roles of alcohol consumption and mental health factors(anxiety and depressive symptoms)in this association.Methods A cross-sectional study design was used to survey 1 336 manufacturing workers in Shenzhen.We collected the data of their demographic characteristics,work-related factors,personal behaviors,sleep disorders,and mental health status.Multivariate Logistic regression analysis was used to assess the association between long working hours and sleep disorders.Stratified analysis and mediation effect models were applied to examine the effect modification by alcohol consumption and the mediating role of mental health factors,respectively.Results Among the study samples,31.8％reported long working hours and 45.6％had sleep disorders.Multivariate Logistic regression analysis showed that long working hours significantly increased the risk of sleep disorders(adjusted OR=2.073,95％ CI:1.478-2.907,P＜0.001).Stratified analysis revealed that the association between long working hours and sleep disorders was more pronounced among alcohol consumers(adjusted OR=2.556,95％ CI:1.432-4.562,P=0.001).Mediation effect analysis showed that anxiety and depressive symptoms partially mediated the relationship between long working hours and sleep disorders,with indirect effects accounting for 25.71％ and 27.14％,respectively.Conclusion Long working hours increase the risk of sleep disorders among manufacturing workers,particularly among those who consume alcohol.Anxiety and depressive symptoms partially explain the association between long working hours and sleep disorders.

Objective:To investigate the expressions of MUC1, MUC4, MUC5AC and MUC16 in patients with first diagnosis of dry eye and their correlation with dry eye symptoms and signs.Methods:A cross-sectional study was conducted.Sixty-nine dry eye patients (69 eyes) as dry eye group and 40 normal volunteers (40 eyes) as normal control group were recruited in Xiamen Eye Center of Xiamen University, Beijing Tongren Hospital, West China Hospital of Sichuan University and Shanghai Puotuo District Center Hospital from December 2016 to May 2018.Symptoms were evaluated by Chinese dry eye questionnaire, Ocular Surface Disease Index (OSDI) and Dry Eye-Related Quality-of-Life Score Questionnaire (DEQS). Signs were assessed by tear film breakup time (TBUT), keratoconjunctival fluorescein sodium staining, and Schirmer I test.Conjunctival cells were collected by conjunctival impression cytology.The expression levels of MUC1, MUC4, MUC5AC and MUC16 mRNA in the two groups were determined by real-time fluorescence quantitative PCR.The correlation between the mRNA levels of conjunctival mucins and dry eye symptoms and signs were analyzed by Spearman correlation analysis.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committees of Xiamen Eye Center of Xiamen University (No.2017003), Beijing Tongren Hospital, Capital Medical University (No.TREC2016-29), West China Hospital of Sichuan University (No.2016310) and Shanghai Puotuo District Center Hospital (No.PTEC-A-2016-18-1). Written informed consent was obtained from each subject before any medical examination.Results:The expression levels of MUC1 and MUC16 mRNA in dry eye patients were 3.277(0.568, 5.790) and 1.815(1.048, 3.694), which were higher than 1.055(0.550, 2.010) and 1.024(0.541, 1.965) in normal control group (Z=819.00, P=0.008; Z=861.00, P=0.002). According to OSDI scores, MUC1 was mainly increased to 3.277(1.161, 6.226) in mild to moderate (12-32 points) dry eye patients (Z=9.04, P=0.029), and MUC16 was mainly increased to 1.968(1.074, 3.726) in severe (>32 points) dry eye patients (Z=12.24, P=0.007). MUC1 expression was positively correlated with TBUT, and was negatively correlated with corneal staining scoring and keratoconjunctival staining scoring ( r s=0.270, P=0.025; r s=-0.331, P=0.006; r s=-0.325, P=0.007). MUC16 expression was positively correlated with TBUT, and was negatively correlated with blurred vision scoring, symptom exacerbation scoring during reading, impact scoring of driving at night, impact scoring of computer and impact scoring of TV use ( r s=0.249, P=0.039; r s=-0.359, P=0.047; r s=-0.370, P=0.034; r s=-0.558, P=0.016; r s=-0.498, P=0.006; rs=-0.515, P=0.002). Conclusions:The gene expressions of MUC1 and MUC16 are higher in conjunctiva of dry eye patients.MUC1 mRNA expression is related to patients' signs.MUC16 mRNA expression is related to the quality of life of patients.

Objective:To analyze the clinical manifestations and signs of the first diagnosed dry eye patients, and to explore the concordance between the Chinese dry eye diagnostic criteria and the Asian dry eye diagnostic criteria.Methods:A cross-sectional multicenter study was conducted.One hundred and forty-one eyes of 141 patients who were diagnosed as dry eye for the first time were included in Xiamen Eye Center of Xiamen University, Beijing Tongren Hospital, West China Hospital of Sichuan University and Shanghai Putuo District Center Hospital from December 2016 to May 2018.All patients completed the Chinese Dry Eye Questionnaire, Ocular Surface Disease Index (OSDI) and Dry Eye-Related Quality-of-life Score Questionnaire (DEQS) to evaluate the symptoms of dry eye.Tear film breakup time (BUT), keratoconjunctival fluorescein staining, meibomian gland morphology and function examination, and Schirmer Ⅰ test were performed to evaluate dry eye signs and the association between dry eye symptoms and signs.The eyes were divided into corneal staining positive and negative group according to the presence or absence of corneal fluorescein staining, and the dry eye symptoms of the two groups were assessed by the three questionnaires.The eyes were divided into tear-deficient dry eye, evaporative dry eye, mixed dry eye and abnormal tear dynamics dry eye to compare the difference of dry eye signs among the groups.This study adhered to the Declaration of Helsinki.The study protocol complied with Chinese regulations and rules on clinical trial research and was approved by Ethics Committees of Xiamen Eye Center of Xiamen University (No.2017003), Beijing Tongren Hospital, Capital Medical University (No.TREC2016-29), West China Hospital of Sichuan University (No.2016310) and Shanghai Putuo District Center Hospital (No.PTEC-A-2016-18-1). Written informed consent was obtained from patients before entering the cohort.Results:The total score of Chinese Dry Eye Questionnaire, OSDI questionnaire and DEQS questionnaire was 12.00(7.00, 16.00), 25.00(17.50, 36.93) and 32.02(15.77, 52.34), respectively.It was found that 130 eyes (92.2%) had dryness, and 109 eyes (77.3%) had ocular fatigue and 108 eyes (76.6%) had foreign body sensation.Dryness, foreign body sensation, photophobia and poor vision were weakly positively correlated with corneal staining ( r=0.177、0.297、0.172, all at P<0.05). Pain, photophobia and poor vision were negatively correlated with tear secretion ( r=-0.178, -0.197, -0.174; all at P<0.05). It was found that 43.3% of dry eye patients had used visual display terminals.Among the 141 eyes, 75 eyes (53.2%) were with over evaporation dry eye, 43 eyes (30.5%) with mixed dry eye, 18 eyes (12.8%) with aqueous-deficient dry eye and 3 eyes (2.1%) with abnormal tear dynamics dry eyes. Conclusions:Initial diagnosis of dry eye patients is mainly mild to moderate.Dry eye signs and symptoms are correlated.Over evaporation dry eye is the most common type of dry eye.The concordance between the Chinese dry eye diagnostic criteria and the Asian Dry Eye Society diagnostic criteria reaches 97.2%.

Objective:To understand the basic situation of noise hazards in wood furniture manufacturing, stone processing and special equipment manufacturing industries in Shenzhen City, and to provide basis for preventing and controlling noise hazards.Methods:In August 2019, stratified random sampling ws used to select 21 wood funiture manafacturing, 15 stone processing and 24 special equipment manufactruing as survey object. Through the methods of occupational health field investigation, noise intensity measurement and occupational health examination data collection, the noise hazards of 60 enterprises in three industries were statistically analyzed.Results:There were 154, 44 and 113 noise detection points in wood furniture manufacturing, stone processing and special equipment manufacturing enterprises, and 101, 27 and 78 out of standard points respectively, and the exceeding standard rates were 65.6% (101/154) , 61.4% (27/44) and 69.0% (78/113) , respectively. There were 1670, 172 and 856 workers exposed to noise in the three industries. Among them, 1198, 134 and 703 people had taken occupational health examination. The physical examination rates were 71.7% (1198/1670) , 77.9% (134/172) and 82.1% (703/856) , respectively. The abnormal rates were 19.1% (229/1198) , 51.5% (69/134) and 37.8% (266/703) , respectively.Conclusion:High intensity noise working environment, too long noise exposure time, incorrect wearing of personal protective equipment and neglect of occupational health examination are important reasons for hearing loss of noise exposed personnel.

Objective:To understand the basic situation of noise hazards in wood furniture manufacturing, stone processing and special equipment manufacturing industries in Shenzhen City, and to provide basis for preventing and controlling noise hazards.Methods:In August 2019, stratified random sampling ws used to select 21 wood funiture manafacturing, 15 stone processing and 24 special equipment manufactruing as survey object. Through the methods of occupational health field investigation, noise intensity measurement and occupational health examination data collection, the noise hazards of 60 enterprises in three industries were statistically analyzed.Results:There were 154, 44 and 113 noise detection points in wood furniture manufacturing, stone processing and special equipment manufacturing enterprises, and 101, 27 and 78 out of standard points respectively, and the exceeding standard rates were 65.6% (101/154) , 61.4% (27/44) and 69.0% (78/113) , respectively. There were 1670, 172 and 856 workers exposed to noise in the three industries. Among them, 1198, 134 and 703 people had taken occupational health examination. The physical examination rates were 71.7% (1198/1670) , 77.9% (134/172) and 82.1% (703/856) , respectively. The abnormal rates were 19.1% (229/1198) , 51.5% (69/134) and 37.8% (266/703) , respectively.Conclusion:High intensity noise working environment, too long noise exposure time, incorrect wearing of personal protective equipment and neglect of occupational health examination are important reasons for hearing loss of noise exposed personnel.

OBJECTIVE: To compare the applicability of two risk assessment methods to assess the occupational health risk of key industries of dichloromethane in Shenzhen City. METHODS: The Singapore ministry of manpower risk(MOM) method and the comprehensive index method were used to evaluate the risk of 123 positions in 47 key industries of dichloromethane in Shenzhen City. Then the risk classification results of the two assessment methods were compared. RESULTS: The results of MOM method showed that the median and the 0 th to 100 th percentile [M(P_0-P_(100))] of risk of dichloromethane in electronics industry was 2(2-3), and the risk level was low to medium. The M(P_0-P_(100)) of risk of dichloromethane in printing industry was 2(2-4), and the risk level was low to high. The results of the comprehensive index method showed that the M(P_0-P_(100)) of risk of dichloromethane in electronics industry and printing industry were 3(3-4), and the risk level was medium to high. There was no significant difference in the assessment results of occupational health risk of dichloromethane between the electronic industry and the printing industry by MOM evaluation method(P>0.05). The occupational health risk assessment of dichloromethane in printing industry was higher than that in electronic industry by the comprehensive index method(P<0.01). Both evaluation methods were not consistent in the electronics industry and the printing industry(k values were-0.01 and 0.04, all P>0.05). After merging the evaluation results of the two industries, there was no consistency in the evaluation results of the two evaluation methods(k value=0.01, P>0.05). CONCLUSION: The risk level of dichloromethane in printing industry is higher than that in printing industry in Shenzhen City. The comprehensive index method may comprehensively and objectively assess the occupational health risk level of dichloromethane in key industries in Shenzhen City.

Objective: To study the changes of monocyte cytokines in peripheral blood of n-hexane neuropathy patients induced by P₀ protein, and to explore the role of autoimmunity in n-hexane neuropathy patients. Methods: In May 2018, 5 patients with peripheral neuropathy diagnosed as n-hexane poisoning were selected as case group in Shenzhen Prevention and Treatment Center for Occupational Disease in 2017. 6 workers exposure to n-hexane and 6 workers without n-hexane exposure were selected as contact group and control group. Peripheral blood mononuclear cells(PBMC) were isolated from venous blood. Results: The number of spots produced by INF-γ and IL-10 increased after stimulation with P₀ protein in case group, and the positive rate was significantly higher than control group and the contact group. Conclusion Autoimmunity induced by P₀ protein may be involved in the occurrence of myelin sheath damage in n-hexane neuropathy patients.

OBJECTIVETo investigate the sensitization effect of different chemical modifiers in the determination of indium in whole blood by graphite furnace atomic absorption spectrometry, and to develop a new method for the determination of indium in whole blood.

METHODSA mixture of 0.3% HNO3 (V/V) + 0.1% Triton X-100 (V/V) was used as a diluent, and a solution of 1 000 µg/ml Pd (NO3)2 + 3 000 µg/ml Mg (NO3)2 was used as modifier. After being diluted five times, the concentration of indium of the blood was directly determined by graphite furnace atomic absorption spectrometry.

RESULTSThe detection limit of the method was 0.33 µg/L, the linear range was 0.33~100.00 µg/L, the relative standard deviation was 1.43%~2.65%, and the recovery rate was 98.3%~105.3%.

CONCLUSIONThe method is simple and fast and has high recovery and precision, and it is suitable for the determination of indium in whole blood.