Objective To investigate the changes of TRPM 7-like current in mouse cardiac fibroblast(CFs) after myocardial infarction and the effect of myocardial ischemia on the TRPM 7 expression and current. Methods (1) The model of myocardial infarction was made and CFs were isolated;(2) CFs were cultured and infected by TRPM 7 siRNA;(3) The effects of myocardial ischemia on TRPM 7 current were recorded by whole cell patch clamp technique;(4) The influences of myocardial isehemia on Ca2+ influx in CFs were recorded by Ca2+ fluorescence imaging. (5) The effects of ischemia on total collagen content of CFs were studied. Results (1) Ca2+ inward current of CFs was increased after myocardial infarction [(16.2±1.7) vs. (7.4±0.7) pA/pF, P<0.053];(2) TRPM 7 current was reduced by 90% after siRNA infection;(3) The total collagen content of CFs after ischemia was approximately 2.3-fold higher than basic value. Conclusions Ca2+ influx in CFs plays an important role in the pathophysiological process of myocardial fibrosis.

Objective: To investigated the effect of long-term low-concentration mixed benzene exposure on peripheral blood of male workers. Methods: A case-control study was conducted to select 452 male workers exposed to mixed benzene (benzene, toluene, xylene) for five consecutive years from January 2012 to December 2016 in an automobile manufacturer as case group, and 438 male administrative and logistic managers who underwent physical examination during the same period as control group. The peripheral blood of the two groups was tested and compared, and the occupational hazards in the workplace were detected. Results: There were low dose exposure to mixed benzene in the enterprise, but the test results met the occupational exposure limit requirements. During the five years from 2010 to 2016, between the two groups of workers, the mean values of WBC, NEUT, RBC and Hb were statistically different (P<0.05). There was no statistical difference (P>0.05) in the mean value of PLT. The abnormal rate of main peripheral blood indexes in the control group was higher than that in the exposed group. There were significant differences in NEUT, RBC and Hb (P< 0.05), but no significant differences in WBC and PLT (P>0.05). Conclusion It can not be concluded that long-term low-concentration mixed benzene exposure can cause the change of peripheral blood index.

Objective: To understand the prevalence of gynecologic diseases among married female workers. Methods: The data of married female workers who underwent occupational health examination in a physical examination center from January to December 2017 were collected. The relationship between the detection of common gynecological diseases, age and occupational types examined by gynecological routine, TCT, breast B-mode ultrasound, uterus and appendix B-mode ultrasound were analyzed. Results: Among the 1142 female workers, the total detection rate of reproductive tract infections was 67.25% (768/1142), the total detection rate of breast-related diseases was 75.22% (859/1142) ; the total detection rate of gynecological tumors and benign lesions was 14.71% (168/1142). The detection rate of breast hyperplasia was the highest 67.08% (766/1142), followed by vaginitis 51.66% (590/1142). Among the abnormalities detected in breast-related diseases, gynecological tumors and benign lesions, the highest detection rate was found in public institutions (85.66% and 27.13%), and the lowest was found in factory workers (70.24% and 7.89%). With the increase of age, the detection rate of breastrelated diseases (breast hyperplasia, breast cyst), gynecological tumors, benign lesions (uterine myoma), and Nessler's cyst abnormalities in married female workers increased (χ²_trend=7.647、21.653、107.411、53.802, P<0.05), while the detection rate of columnar epithelium of cervix decreased (χ²_trend=7.404, P<0.05). There was no significant difference in the total detection rate of reproductive tract infectious diseases (vaginitis, cervical polyps, cervical hypertrophy) among married famale workers of different ages (P<0.05) . Conclusion The common gynecological diseases of married female workers are affected by many factors such as age and occupation. Health examination and health education should be carried out regularly to reduce the incidence of gynecological diseases among female workers according to different ages and occupations.

OBJECTIVE: To investigate the prevalence of metabolic syndrome(MetS) and its related influencing factors among male workers in several industries in Guangzhou City.METHODS: A total of 2 987 male workers were selected by convenience sampling method and the occupational health physical exam data from 2012 to 2015 was collected.The MetS was diagnosed according to the diagnostic criteria proposed by the Chinese Medical Association Diabetes Association.The analysis of correlation factors was conducted by the generalized estimating equation method.RESULTS: The diastolic blood pressure of subjects increased year by year(P<0.01) and high-density lipoprotein cholesterol(HDL-C) decreased year by year(P<0.01) from 2012 to 2015,but the changes of body mass index,systolic blood pressure and levels of fasting plasma glucose,triglyceride didn't increase or decrease over time.The prevalence of high blood pressure,high glycemia,high TG,low HDL-C and MetS were found to increase year by year(P<0.01) from 2012 to 2015.The generalized estimating equation analysis results showed service length,family history(hypertension and/or diabetes),regular alcohol consumption,frequent smoking,oily diet and meat-rich diet were the risk factors of MetS(P<0.05) after adjusting the confounding factors of age.CONCLUSION: The incidence of MetS in male workers in Guangzhou City is increasing year by year.The service lengh,family history(hypertension and/or diabetes),regular alcohol consumption,regular smoking,oily diet and meat-rich diet are associated with the prevalence of MetS in this population.

OBJECTIVE: To explore the 2014 edition of the diagnostic criteria of occupational noise-induced deafness on the assessment of hearing loss in occupational health examination. METHODS: A total of 835 noise-exposed workers were selected as study subjects by cluster sampling method. The hearing threshold results were compared through two different editions of criteria: GBZ 49-2007 Diagnostic Criteria of Occupational Noise-induced Deafness( GBZ 49-2007) and GBZ 49-2014 Diagnosis of Occupational Boise-induced Deafness( GBZ 49-2014). RESULTS: The binaural high frequency threshold average calculated by GBZ 49-2007 was lower than that of GBZ 49-2014 [( 46. 8 ± 8. 1) vs( 49. 2 ± 8. 0) d B,P < 0. 01].The speech frequency threshold average of the good ear calculated by GBZ 49-2007 was lower than the monaural threshold of weighted value of the good ear of GBZ 49-2014 [( 18. 8 ± 3. 6) vs( 22. 0 ± 3. 3),P < 0. 01]. The speech frequency threshold average of the good ear and the monaural threshold of weighted value of the good ear calculated after age and sex correction using GBZ 49-2007 were lower than that calculated by using GBZ 49-2014 [( 18. 8 ± 3. 6) vs( 19. 4 ± 3. 6),( 21. 5 ±3. 4) vs( 22.0 ±3.3),P <0.05]. The detection rate of suspected occupational noise-induced deafness GBZ 49-2014 was higher than that of GBZ 49-2007( 6. 35% vs 2. 87%,P < 0. 01). CONCLUSION: In occupational health examination,the diagnostic criteria of GBZ 49-2014 can diagnose patients as suspected occupational noise-induced deafness easier than that of GBZ 49-2007.

OBJECTIVE: To analyze the effect of noise exposure on the hearing ability at different frequency in workers.METHODS: A total of 2 411 workers in a mechanical plant in Guangzhou were chosen as the study subjects by using judgment sampling method. The pure tone audiometry threshold test was carried out to analyze the status of hearing loss at different frequencies and its relationship with the length of service of workers. RESULTS: Among the 2 411 workers,883 workers had different degrees of decreased hearing thresholds,the detection rate was 36. 6%. Among them,the single unilateral hearing loss accounted for 19. 6%( 472/2 411),and the binaural hearing loss was 17. 0%( 411/2 411). The hearing loss detection rate of left ear was higher than that of the right ear( P < 0. 05). The decreased threshold of left ear at 0. 5,3. 0 and 6. 0 kHz was higher than that of the right ear at the same frequencies( P < 0. 05). The decreased threshold in both the left and the right ear increased with the increase of the frequency( P < 0. 01). The decreased hearing threshold was the highest at the frequency of 6. 0 kHz. The auditory threshold of left ear in 0. 5,1. 0,2. 0,3. 0 and 6. 0 kHz were higher than that of right ear at the same frequencies( P < 0. 05). The detection rate of hearing loss increased with the increase of service length( P < 0. 01). The decreased threshold of 1. 0-6. 0 kHz increased with the increased length of service except for the frequency of 0. 5 kHz( P < 0. 05). CONCLUSION: There is a significant decreased threshold in workers exposed to noise frequency of 6. 0 kHz. The hearing ability of left ear is more easily impaired than the right ear.There is a dose-response relationship for the length of noise exposure and hearing loss.

OBJECTIVE: To investigate the prevalence of chronic diseases and main influencing factors in workers under high-temperature in a port of Guangzhou City.METHODS: A total of 5 603 workers under high-temperature operation condition were selected by judgment sampling method.The occupational health examination results were collected to analyze the prevalence of chronic diseases and the related influencing factors.RESULTS: The prevalence of chronic diseases was 67.6%.The prevalence rates of hyperlipidemia,hyperuricemia,hypertension and diabetes were 51.8%,29.3%,14.0% and 10.2%,respectively.Multivariate logistic regression analysis indicated that the risks of hyperlipidemia,hyperuricemia and hypertension in male workers were higher than that of female workers( P < 0.05).The prevalence risk of hyperlipidemia,hypertension and diabetes increased with the increase age( P < 0.01).With the increase of the length of high-temperature operation,the risk of hyperlipidemia,hyperuricemia and hypertension increased( P < 0.01).The risk of hypertension in regular smokers was higher than that of non-smokers( P < 0.05).The less exercise,the higher risk of hypertension and diabetes( P < 0.01).CONCLUSION: The prevalence of chronic diseases is high in workers exposed to high-temperature.The gender,age,length of high-temperature operation,smoking and exercise were the major influencing factors of chronic diseases in the workers.

OBJECTIVE: To explore the detection of small airway dysfunction in occupational populations and its influencing factors. METHODS: A convenient sampling method was adopted, and 15 490 occupational health workers who were tested for pulmonary ventilation function in 2018 were selected as study subjects. The results of pulmonary ventilation function examination and chest direct digital radiography(DR) were collected and analyzed. RESULTS: Among the study subjects, 2 083 were detected to have abnormal pulmonary ventilation function, the abnormal detection rate was 13.4%; 3 089 subjects were detected to have small airway dysfunction, and the abnormal detection rate was 19.9%. The two-class logistic regression analysis results suggested that female, exposure to organic dusts during work, exposure to asthmogenic during work, chest DR abnormalities and abnormal pulmonary ventilation function were risk factors for abnormal small airway function(P<0.05). CONCLUSION: The abnormal small airway function in occupational populations is related to various factors such as gender and occupational exposure to allergens. The screening of small airway function in this group may help advance the prevention and treatment of respiratory diseases.

Background Some studies have found that exposure to heavy metals significantly increases the risk of nonalcoholic fatty liver disease (NAFLD), and welding operators in automobile manufacturing enterprises are exposed to heavy metals in the working environment. Objective To analyze the prevalence and related factors of NAFLD in workers of an automobile company in Guangzhou. Methods From January 1 of 2023 to December 31 of 2023, 5463 workers of an automobile company in Guangzhou who participated in the physical examination in the Occupational Health Surveillance Centre of Guangzhou Occupational Disease Prevention and Treatment Hospital were selected as research subjects. The general data, laboratory examinations, B-ultrasound examinations, and other data of the subjects were obtained through the physical examination system. The exposed occupational hazards were identified based on the workplace hazard surveillance report provided by the automotive company. Logistic regression was used to analyze potential influencing factors of NAFLD, and stratified analysis was used to adjust confounding factors according to the stepwise model to evaluate the relationship between exposure to manganese and its inorganic compounds and NAFLD. Results A total of 2129 cases (38.97%) were reported positive NAFLD. The results of logistic regression analysis showed that women had a lower risk of NAFLD (OR=0.40, 95%CI: 0.25, 0.64), while age > 25 years old (OR=1.49, 95%CI: 1.39, 1.60), body mass index (BMI) ≥24 kg·m⁻² (OR=7.54, 95%CI: 6.46, 8.79), and elevated alanine aminotransferase (ALT) (OR=4.87, 95%CI: 3.73, 6.36), γ-glutamyl transpeptidase (γ-GGT) (OR=1.54, 95%CI: 1.17, 2.02), triglyceride (TG) (OR=3.47, 95%CI: 2.92, 4.14), and fasting blood glucose (OR=1.70, 95%CI: 1.32, 2.20) associated with a higher risk of NAFLD. NAFLD was positive in 39.40% of heavy metal exposed workers (701/1779). NAFLD was positive in 45.19% of workers exposed to manganese and its inorganic compounds (169/374), and among workers over 34 years old, exposure to manganese and its inorganic compounds (OR=1.79, 95%CI: 1.07, 2.97) significantly increased the prevalence of NAFLD. Conclusion The association between heavy metal exposure and NAFLD in workers of an automobile enterprise in Guangzhou is not significant, but age and gender are related to the prevalence of NAFLD. BMI, ALT, γ-GGT, TG, and fasting blood glucose are positively correlated with the prevalence of NAFLD. Exposure to manganese and its inorganic compounds in welding workers of the automobile enterprise is associated with elevated risk of the disease, and the prevalence of NAFLD is significantly increased in workers over 34 years old.