1.Analysis of earplugs protective and intervention effect of 220 noise exposed workers
Yanan WANG ; Weitao LIN ; Chunhua LIAO ; Lei LU ; Shibiao SU
Chinese Journal of Industrial Hygiene and Occupational Diseases 2025;43(8):590-594
Objective:To investigate the use of earplugs among noise-exposed workers (Homo sapiens) in Bao'an District, Shenzhen, measure the personal attenuation rating (PAR) of earplugs when wearing earplugs, (Homo sapiens), analyze factors influencing the protective effect of earplugs, and evaluate the role of targeted wearing interventions in improving protective efficacy.Methods:From December 2022 to January 2023, 220 workers in noise-exposed positions from 3 enterprises in Bao'an District, Shenzhen were selected as subjects using the convenience sampling method. The Personal Attenuation Rating (PAR) values of workers wearing earplugs were measured using a fit testing system. Combined with the results of a questionnaire survey, the individual differences in workers' baseline PAR were described. A multivariate logistic regression model was used to analyze the influencing factors for earplugs to achieve the protective effect. One-on-one wearing interventions were implemented for workers who failed to achieve the protective effect, and repeated PAR tests were conducted. The changes in PAR of 120 workers before and after the intervention were compared.Results:The median baseline PAR for 220 workers was 7 (0, 14) dB, and the intervention rate was 54.55% (120/220). There were differences in the baseline PAR of workers with different length of service, earplugs wearing time and experience, daily noise exposure time and intensity, training and the comfort of earplug use ( P<0.05). The results of multivariate regression analysis showed that workers The comfort with earplugs wearing ( OR=2.81, 95% CI: 1.49~5.33, P<0.01) and training ( OR=6.60, 95% CI: 1.70~25.63, P<0.05) were the influencing factors of achieving the protective requirement. The median PAR was increased to 13 (11, 16) dB after intervention. Conclusion:The baseline protective effect of earplugs worn by workers is significantly influenced by comfort and enterprise training. One-on-one interventions can effectively improve the protective efficacy of those who fail to meet the requirements.
2.National bloodstream infection bacterial resistance surveillance report 2023: Gram-positive bacteria
Chaoqun YING ; Jinru JI ; Zhiying LIU ; Qing YANG ; Haishen KONG ; Jiangqin SONG ; Hui DING ; Yanyan LI ; Yuanyuan DAI ; Haifeng MAO ; Pengpeng TIAN ; Lu WANG ; Yongyun LIU ; Yizheng ZHOU ; Jiliang WANG ; Yan JIN ; Donghong HUANG ; Hongyun XU ; Peng ZHANG ; Xinhua QIANG ; Hong HE ; Lin ZHENG ; Junmin CAO ; Zhou LIU ; Ying HUANG ; Yan GENG ; Haiquan KANG ; Dan LIU ; Guolin LIAO ; Lixia ZHANG ; Fenghong CHEN ; Yanhong LI ; Baohua ZHANG ; Haixin DONG ; Xiaoyan LI ; Donghua LIU ; Qiuying ZHANG ; Xuefei HU ; Liang GUO ; Sijin MAN ; Dijing SONG ; Rong XU ; Youdong YIN ; Kunpeng LIANG ; Aiyun LI ; Zhuo LI ; Hongxia HU ; Guoping LU ; Jinhua LIANG ; Qiang LIU ; Yinqiao DONG ; Jilu SHEN ; Shuyan HU ; Liang LUAN ; Jian LI ; Ling MENG ; Dengyan QIAO ; Xiusan XIA ; Bo QUAN ; Dahong WANG ; Chunhua HAN ; Xiaoping YAN ; Fei LI ; Shifu WANG ; Ping SHEN ; Yunbo CHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2025;18(2):118-132
Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System(BRICS)during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute(CLSI). Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus( n=1 544,35.2%),coagulase-negative Staphylococci( n=1 441,32.9%), Enterococcus faecium( n=574,13.1%), Enterococcus faecalis( n=385,8.8%),and α-hemolytic Streptococci( n=187,4.3%). The prevalence of methicillin-resistant Staphylococcus aureus(MRSA)and methicillin-resistant coagulase-negative Staphylococci(MRCNS)was 26.2%(405/1 544)and 69.8%(1 006/1 441),respectively. Notably,all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility(>97.0%)to cephalobiol,rifampicin,trimethoprim-sulfamethoxazole,linezolid,minocycline,tigecycline,and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium(resistance to vancomycin and teicoplanin:both 1.7%)compared to Enterococcus faecalis(both 0.3%). The detection rates of MRSA and MRCNS exhibited significant regional variations across the country( χ2=17.674 and 148.650,respectively,both P<0.001). No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA( χ2=14.111, P<0.001)and MRCNS( χ2=4.828, P=0.028)in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA( χ2=18.986, P<0.001)and MRCNS( χ2=4.477, P=0.034)in less developed regions(per capita GDP
3.National bloodstream infection bacterial resistance surveillance report (2023) : Gram-negative bacteria
Jinru JI ; Zhiying LIU ; Chaoqun YING ; Qing YANG ; Haishen KONG ; Jiangqin SONG ; Hui DING ; Yanyan LI ; Yuanyuan DAI ; Haifeng MAO ; Pengpeng TIAN ; Lu WANG ; Yongyun LIU ; Yizheng ZHOU ; Jiliang WANG ; Yan JIN ; Donghong HUANG ; Hongyun XU ; Peng ZHANG ; Xinhua QIANG ; Hong HE ; Lin ZHENG ; Junmin CAO ; Zhou LIU ; Ying HUANG ; Yan GENG ; Haiquan KANG ; Dan LIU ; Guolin LIAO ; Lixia ZHANG ; Fenghong CHEN ; Yanhong LI ; Baohua ZHANG ; Haixin DONG ; Xiaoyan LI ; Donghua LIU ; Qiuying ZHANG ; Xuefei HU ; Liang GUO ; Sijin MAN ; Dijing SONG ; Rong XU ; Youdong YIN ; Kunpeng LIANG ; Aiyun LI ; Zhuo LI ; Hongxia HU ; Guoping LU ; Jinhua LIANG ; Qiang LIU ; Yinqiao DONG ; Jilu SHEN ; Shuyan HU ; Liang LUAN ; Jian LI ; Ling MENG ; Dengyan QIAO ; Xiusan XIA ; Bo QUAN ; Dahong WANG ; Chunhua HAN ; Xiaoping YAN ; Fei LI ; Shifu WANG ; Ping SHEN ; Yunbo CHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2025;18(1):47-62
Objective:To report the results of bacterial resistant investigation collaborative system(BRICS)on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023,and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute(CLSI). WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period,11 492 strains of Gram-negative bacteria were collected from 60 hospitals,of which 10 098(87.9%)were Enterobacterales and 1 394(12.1%)were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli(50.0%), Klebsiella pneumoniae(26.1%), Pseudomonas aeruginosa(5.1%), Acinetobacter baumannii complex(5.0%)and Enterobacter cloacae complex(4.1%). The ESBL-producing rates in Escherichia coli, Klebsiella pneumoniae and Proteus mirablilis were 46.8%(2 685/5 741),18.3%(549/2 999)and 44.0%(77/175),respectively. The prevalence of carbapenem-resistant Escherichia coli(CREC)and carbapenem-resistant Klebsiella pneumoniae(CRKP)were 1.3%(76/5 741)and 15.0%(450/2 999);32.9%(25/76)and 78.0%(351/450)of CREC and CRKP were sensitive to ceftazidime/avibactam combination,respectively. 94.7%(72/76)and 90.2%(406/450)of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore,57.9%(44/76)and 79.1%(356/450)were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)complex was 64.6%(370/573),while more than 80.0% of CRAB complex was sensitive to tigecycline,eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa(CRPA)was 17.0%(99/581). There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China,with statistically significant differences in the prevalence of CREC,CRKP,CRPA and CRAB complex( χ2=10.6,28.6,10.8 and 19.3, P<0.05). The prevalence of ESBL-producing Escherichia coli, CREC,CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals( χ2=12.5,9.8,12.7 and 57.8,all P<0.01). Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China,and Escherichia coli is ranked in the top,while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend,CREC infecton maintains a low prevalence level,and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.
4.Analysis of earplugs protective and intervention effect of 220 noise exposed workers
Yanan WANG ; Weitao LIN ; Chunhua LIAO ; Lei LU ; Shibiao SU
Chinese Journal of Industrial Hygiene and Occupational Diseases 2025;43(8):590-594
Objective:To investigate the use of earplugs among noise-exposed workers (Homo sapiens) in Bao'an District, Shenzhen, measure the personal attenuation rating (PAR) of earplugs when wearing earplugs, (Homo sapiens), analyze factors influencing the protective effect of earplugs, and evaluate the role of targeted wearing interventions in improving protective efficacy.Methods:From December 2022 to January 2023, 220 workers in noise-exposed positions from 3 enterprises in Bao'an District, Shenzhen were selected as subjects using the convenience sampling method. The Personal Attenuation Rating (PAR) values of workers wearing earplugs were measured using a fit testing system. Combined with the results of a questionnaire survey, the individual differences in workers' baseline PAR were described. A multivariate logistic regression model was used to analyze the influencing factors for earplugs to achieve the protective effect. One-on-one wearing interventions were implemented for workers who failed to achieve the protective effect, and repeated PAR tests were conducted. The changes in PAR of 120 workers before and after the intervention were compared.Results:The median baseline PAR for 220 workers was 7 (0, 14) dB, and the intervention rate was 54.55% (120/220). There were differences in the baseline PAR of workers with different length of service, earplugs wearing time and experience, daily noise exposure time and intensity, training and the comfort of earplug use ( P<0.05). The results of multivariate regression analysis showed that workers The comfort with earplugs wearing ( OR=2.81, 95% CI: 1.49~5.33, P<0.01) and training ( OR=6.60, 95% CI: 1.70~25.63, P<0.05) were the influencing factors of achieving the protective requirement. The median PAR was increased to 13 (11, 16) dB after intervention. Conclusion:The baseline protective effect of earplugs worn by workers is significantly influenced by comfort and enterprise training. One-on-one interventions can effectively improve the protective efficacy of those who fail to meet the requirements.
5.National bloodstream infection bacterial resistance surveillance report 2023: Gram-positive bacteria
Chaoqun YING ; Jinru JI ; Zhiying LIU ; Qing YANG ; Haishen KONG ; Jiangqin SONG ; Hui DING ; Yanyan LI ; Yuanyuan DAI ; Haifeng MAO ; Pengpeng TIAN ; Lu WANG ; Yongyun LIU ; Yizheng ZHOU ; Jiliang WANG ; Yan JIN ; Donghong HUANG ; Hongyun XU ; Peng ZHANG ; Xinhua QIANG ; Hong HE ; Lin ZHENG ; Junmin CAO ; Zhou LIU ; Ying HUANG ; Yan GENG ; Haiquan KANG ; Dan LIU ; Guolin LIAO ; Lixia ZHANG ; Fenghong CHEN ; Yanhong LI ; Baohua ZHANG ; Haixin DONG ; Xiaoyan LI ; Donghua LIU ; Qiuying ZHANG ; Xuefei HU ; Liang GUO ; Sijin MAN ; Dijing SONG ; Rong XU ; Youdong YIN ; Kunpeng LIANG ; Aiyun LI ; Zhuo LI ; Hongxia HU ; Guoping LU ; Jinhua LIANG ; Qiang LIU ; Yinqiao DONG ; Jilu SHEN ; Shuyan HU ; Liang LUAN ; Jian LI ; Ling MENG ; Dengyan QIAO ; Xiusan XIA ; Bo QUAN ; Dahong WANG ; Chunhua HAN ; Xiaoping YAN ; Fei LI ; Shifu WANG ; Ping SHEN ; Yunbo CHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2025;18(2):118-132
Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System(BRICS)during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute(CLSI). Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus( n=1 544,35.2%),coagulase-negative Staphylococci( n=1 441,32.9%), Enterococcus faecium( n=574,13.1%), Enterococcus faecalis( n=385,8.8%),and α-hemolytic Streptococci( n=187,4.3%). The prevalence of methicillin-resistant Staphylococcus aureus(MRSA)and methicillin-resistant coagulase-negative Staphylococci(MRCNS)was 26.2%(405/1 544)and 69.8%(1 006/1 441),respectively. Notably,all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility(>97.0%)to cephalobiol,rifampicin,trimethoprim-sulfamethoxazole,linezolid,minocycline,tigecycline,and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium(resistance to vancomycin and teicoplanin:both 1.7%)compared to Enterococcus faecalis(both 0.3%). The detection rates of MRSA and MRCNS exhibited significant regional variations across the country( χ2=17.674 and 148.650,respectively,both P<0.001). No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA( χ2=14.111, P<0.001)and MRCNS( χ2=4.828, P=0.028)in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA( χ2=18.986, P<0.001)and MRCNS( χ2=4.477, P=0.034)in less developed regions(per capita GDP
6.National bloodstream infection bacterial resistance surveillance report (2023) : Gram-negative bacteria
Jinru JI ; Zhiying LIU ; Chaoqun YING ; Qing YANG ; Haishen KONG ; Jiangqin SONG ; Hui DING ; Yanyan LI ; Yuanyuan DAI ; Haifeng MAO ; Pengpeng TIAN ; Lu WANG ; Yongyun LIU ; Yizheng ZHOU ; Jiliang WANG ; Yan JIN ; Donghong HUANG ; Hongyun XU ; Peng ZHANG ; Xinhua QIANG ; Hong HE ; Lin ZHENG ; Junmin CAO ; Zhou LIU ; Ying HUANG ; Yan GENG ; Haiquan KANG ; Dan LIU ; Guolin LIAO ; Lixia ZHANG ; Fenghong CHEN ; Yanhong LI ; Baohua ZHANG ; Haixin DONG ; Xiaoyan LI ; Donghua LIU ; Qiuying ZHANG ; Xuefei HU ; Liang GUO ; Sijin MAN ; Dijing SONG ; Rong XU ; Youdong YIN ; Kunpeng LIANG ; Aiyun LI ; Zhuo LI ; Hongxia HU ; Guoping LU ; Jinhua LIANG ; Qiang LIU ; Yinqiao DONG ; Jilu SHEN ; Shuyan HU ; Liang LUAN ; Jian LI ; Ling MENG ; Dengyan QIAO ; Xiusan XIA ; Bo QUAN ; Dahong WANG ; Chunhua HAN ; Xiaoping YAN ; Fei LI ; Shifu WANG ; Ping SHEN ; Yunbo CHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2025;18(1):47-62
Objective:To report the results of bacterial resistant investigation collaborative system(BRICS)on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023,and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute(CLSI). WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period,11 492 strains of Gram-negative bacteria were collected from 60 hospitals,of which 10 098(87.9%)were Enterobacterales and 1 394(12.1%)were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli(50.0%), Klebsiella pneumoniae(26.1%), Pseudomonas aeruginosa(5.1%), Acinetobacter baumannii complex(5.0%)and Enterobacter cloacae complex(4.1%). The ESBL-producing rates in Escherichia coli, Klebsiella pneumoniae and Proteus mirablilis were 46.8%(2 685/5 741),18.3%(549/2 999)and 44.0%(77/175),respectively. The prevalence of carbapenem-resistant Escherichia coli(CREC)and carbapenem-resistant Klebsiella pneumoniae(CRKP)were 1.3%(76/5 741)and 15.0%(450/2 999);32.9%(25/76)and 78.0%(351/450)of CREC and CRKP were sensitive to ceftazidime/avibactam combination,respectively. 94.7%(72/76)and 90.2%(406/450)of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore,57.9%(44/76)and 79.1%(356/450)were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)complex was 64.6%(370/573),while more than 80.0% of CRAB complex was sensitive to tigecycline,eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa(CRPA)was 17.0%(99/581). There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China,with statistically significant differences in the prevalence of CREC,CRKP,CRPA and CRAB complex( χ2=10.6,28.6,10.8 and 19.3, P<0.05). The prevalence of ESBL-producing Escherichia coli, CREC,CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals( χ2=12.5,9.8,12.7 and 57.8,all P<0.01). Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China,and Escherichia coli is ranked in the top,while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend,CREC infecton maintains a low prevalence level,and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.
7.Electron density map from spectral CT combined with CT features for differentiating acute and chronic osteoporotic vertebral fractures
Dongfeng XU ; Chunhua MAI ; Kaibang ZHU ; Wenzhang WANG ; Yuting LIAO ; Haoya WANG
Chinese Journal of Medical Imaging Technology 2024;40(1):98-102
Objective To observe the value of electron density map(EDM)from spectral CT combined with CT features in differentiating acute and chronic osteoporotic vertebral fractures(OVF).Methods Thoracic and/or lumbar spectral CT data of 48 patients with acute complicated chronic OVF were retrospectively analyzed.Totally 110 fractured vertebrae were enrolled,including 53 vertebrae with acute fractures(acute group)and 57 with chronic fractures(chronic group).The quantitative parameters of spectral CT,including CT values of conventional 120 kVp polyenergetic image(PI,i.e.routine CT images)and 40,70,100 keV virtual monoenergetic images(VMI),effective atomic number(Z-eff)and electron density(ED),as well as routine CT finding were compared between groups,and those being significantly different were included in multivariate logistic regression to screen the independent risk factors for acute OVF and construct a combined model.Receiver operating characteristic(ROC)curves were drawn to evaluate the efficacy of each single independent risk factor and the combination for differentiating acute and chronic OVF.Results Significant differences of all spectral CT quantitative parameters,also of routine CT findings including interruption of vertebral endplate,cortical folds,increased vertebral density,gas within vertebral body and vertebral compression degree were found between groups(all P<0.05).Logistic regression analysis showed that CTPI(OR=0.855,P=0.005),ED(OR=16.432,P=0.005),cortical folds(OR=0.038,P=0.034)and increased vertebral density(OR=0.025,P=0.013)were all independent risk factors for acute OVF.The area under the curve(AUC)of the above single parameters for identifying acute and chronic OVF was 0.870,0.889,0.879 and 0.866,respectively,all lower than that of the combined model(0.977)(Z=3.47,3.73,2.95,2.71,all P<0.05).Conclusion Spectral CT EDM combined with CT findings could effectively differentiate acute and chronic OVF.
8.Study on the fit testing for the workers wearing hearing protection device in machinery manufacturing enterprises
Yanan WANG ; Shibiao SU ; Chunhua LIAO ; Xi ZHONG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2024;42(1):16-21
Objective:To investigate the occupational noise hazards in five machinery manufacturing enterprises, and to evaluate the individual noise reduction values and influencing factors of workers wearing hearing protection device (HPD) by individual fit testing.Methods:From November 2021 to January 2022, 5 machinery manufacturing enterprises in Bao'an District of Shenzhen were selected to conduct an occupational health survey to understand the noise exposure level of workers. The 3MTM E-A-RfitTM fitness test system was used to test the baseline individual sound attenuation value level (PAR) of the daily wear of the ear protecters for 485 workers in typical noise working positions. Workers whose PAR values could not meet the requirements of noise reduction at work were instructed to wear and repeated tests were conducted. PAR results of the workers before and after the intervention were collected and analyzed.Results:The noise workers who received the suitability test were mainly distributed in 24 types of work, the job noise exposure level was 80.2 dB (A) ~ 95.0 dB (A), and the job noise excess rate was 52.5% (138/263). The median baseline PAR [ M ( Q1, Q3) ] for 485 workers was 6.0 (0.0, 14.0) dB. The baseline PAR of male workers, those with more than 15 years of working experience, those with more than 15 years of using ear guards, those who considered ear guards comfortable to wear, those with college degree or above, and those exposed to noise level 90 dB (A) were higher, and the difference was statistically significant ( P<0.05). A total of 275 workers (56.7%) did not pass the baseline PAR test, and there was no statistically significant difference in the intervention rate of workers in different noise groups ( P>0.05). PAR in subjects who did not pass baseline after intervention increased from 0.0 (0.0, 3.0) dB to 15.0 (12.0, 18.2) dB. Conclusion:The workplace noise hazard of machinery manufacturing enterprises is serious, and there is a great difference between the baseline PAR and the nominal value of the hearing guard worn by the noise exposed workers. The intervention measures can effectively improve the protective effect of wearing ear protectors.
9.Functional site analysis of mucin 1 in regulating the malignant characteristics of tumor cells
Kexing GAO ; Chunhua LIAO ; Shengze LI ; Shuangyu MA ; Lei HUANG
Journal of Shanghai Jiaotong University(Medical Science) 2024;44(11):1370-1382
Objective·To identify the functional motifs of mucin 1(MUC1)involved in regulating tumor cell proliferation,migration,and stemness maintenance.Methods·Mutational characteristics of the MUC1 gene across different cancers were identified from The Cancer Genome Atlas(TCGA)database.Various MUC1 mutation sites were analyzed and localized,followed by ranking based on mutation frequency.Western blotting was used to screen high-frequency MUC1 mutants with stable protein expression.BT549 cell line with MUC1 knocked out and MCF-10A cell line were used to stably overexpress MUC1 wild-type(MUC1-WT)and mutants by using lentiviral technology.Immunofluorescence was used to detect the cellular localization of MUC1 mutants.Using MUC1-WT as a positive control and MUC1-AQA,a loss-of-function mutant,as a negative control,the biological functions of different MUC1 mutant cells were analyzed:cell proliferation ability was assessed by cell counting kit-8(CCK-8)assay and colony formation assay;cell migration ability was evaluated by wound-healing and Transwell assays;cell stemness was examined by sphere formation assay.Structural localization of MUC1 mutants was analyzed by using PyMOL software,and molecular docking analysis was performed by using a protein docking software(ZDOCK Server).Results·A total of 102 mutations located in the MUC1 coding region were identified in the TCGA database,among which five missense mutations(P418S,S251R,V359I,N271S,and N465H)exhibited higher frequencies and were located in the non-variable number of tandem repeats(non-VNTR)region.Further examination revealed that the MUC1-S251R,N271S,and V359I mutants could be stably expressed.The cellular localization assay indicated that these three mutants predominantly localized in the cytoplasm,but were also presented in the nucleus.The nuclear-to-cytoplasmic ratio showed minimal differences between MUC1-WT and the mutants.Analysis of the tumorigenic biological functions of the cells expressing different MUC1 mutants revealed that:① High expression of MUC1-WT significantly enhanced the proliferation ability of both BT549 and MCF-10A cells;the proliferation of MUC1-AQA,S251R,and N271S mutant cells was decreased compared to MUC1-WT cells,while MUC1-V359I mutant cells exhibited a similar proliferative profile to MUC1-WT cells.② The migration ability of MUC1-WT high-expressing cells was significantly enhanced,whereas MUC1-AQA cells demonstrated attenuated migration.In the BT549 cells,the migration ability of MUC1-S251R and V359I cells was similar to that of MUC1-WT cells,whereas MUC1-N271S cells showed reduced migration.In the MCF-10A cells,the migration ability of MUC1-N271S and MUC1-V359I cells was similar to that of MUC1-WT cells,whereas MUC1-S251R cells exhibited significantly decreased migration.③ Stemness was enhanced in both cell types with high MUC1-WT expression,while MUC1-AQA cells lost stemness;the cells with MUC1-N271S,V359I and MUC1-WT showed comparable maintenance of stemness,whereas MUC1-S251R cells demonstrated compromised stemness.PyMOL software analysis unveiled that MUC1-N271S and V359I were located in or around the sperm protein-enterokinase-agarin(SEA)region,specifically in the loop region and the β-sheet,respectively.The molecular docking analysis revealed that the stability of the complex formed by MUC1-WT or V359I with the extracellular domain of epidermal growth factor receptor(EGFR)surpassed that of MUC1-N271S or S251R,indicating a stability hierarchy of V359I>WT>N271S>S251R.Conclusion·MUC1 mutants exhibit diverse impacts on the biological functions of tumor cells,with their effects on proliferation correlating with the EGFR signaling pathway.MUC1-V359I is similar to MUC1-WT,indicating a negligible effect on tumor cell proliferation,migration,and stemness maintenance.Conversely,MUC1-S251 and N271 sites may be involved in the regulation of signaling pathways governing cell proliferation and migration and the MUC1-S251 site plays a critical role in maintaining cell stemness.
10.Study on the fit testing for the workers wearing hearing protection device in machinery manufacturing enterprises
Yanan WANG ; Shibiao SU ; Chunhua LIAO ; Xi ZHONG
Chinese Journal of Industrial Hygiene and Occupational Diseases 2024;42(1):16-21
Objective:To investigate the occupational noise hazards in five machinery manufacturing enterprises, and to evaluate the individual noise reduction values and influencing factors of workers wearing hearing protection device (HPD) by individual fit testing.Methods:From November 2021 to January 2022, 5 machinery manufacturing enterprises in Bao'an District of Shenzhen were selected to conduct an occupational health survey to understand the noise exposure level of workers. The 3MTM E-A-RfitTM fitness test system was used to test the baseline individual sound attenuation value level (PAR) of the daily wear of the ear protecters for 485 workers in typical noise working positions. Workers whose PAR values could not meet the requirements of noise reduction at work were instructed to wear and repeated tests were conducted. PAR results of the workers before and after the intervention were collected and analyzed.Results:The noise workers who received the suitability test were mainly distributed in 24 types of work, the job noise exposure level was 80.2 dB (A) ~ 95.0 dB (A), and the job noise excess rate was 52.5% (138/263). The median baseline PAR [ M ( Q1, Q3) ] for 485 workers was 6.0 (0.0, 14.0) dB. The baseline PAR of male workers, those with more than 15 years of working experience, those with more than 15 years of using ear guards, those who considered ear guards comfortable to wear, those with college degree or above, and those exposed to noise level 90 dB (A) were higher, and the difference was statistically significant ( P<0.05). A total of 275 workers (56.7%) did not pass the baseline PAR test, and there was no statistically significant difference in the intervention rate of workers in different noise groups ( P>0.05). PAR in subjects who did not pass baseline after intervention increased from 0.0 (0.0, 3.0) dB to 15.0 (12.0, 18.2) dB. Conclusion:The workplace noise hazard of machinery manufacturing enterprises is serious, and there is a great difference between the baseline PAR and the nominal value of the hearing guard worn by the noise exposed workers. The intervention measures can effectively improve the protective effect of wearing ear protectors.

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