Objective: To investigate the characteristics of acoustic impedance test and its diagnostic role for occupational noise induced deafness, in order to provide an objective basis for the differential diagnosis of occupational noise induced deafness. Methods: A retrospective study was conducted to investigate the cases on the diagnosis of occupational noise-induced deafness in Guangdong province hospital for occupational disease prevention and treatment from January 2016 to January 2017. A total of 198 cases (396 ears) were divided into occupation disease group and non occupation disease group based on the diagnostic criteria of occupational noise deafness in 2014 edition, acoustic conductivity test results of two groups were compared including tympanograms types, external auditory canal volume, tympanic pressure, static compliance and slope. Results: In the occupational disease group, 204 ears were found to have 187 ears (91.67%) of type A, which were significantly higher than those in the non occupational disease group 143/192 (74.48%) , the difference was statistically significant (χ²=21.038, P<0.01). Detection of Ad or As type, occupation disease group in other type were 16/204 (7.84%) , 3/204 (1.47%) , were lower than Ad or As type of occupation disease group (15.63%) , other type (9.38%) , the differences were statistically significant[ (χ²=5.834, P<0.05) , (χ²=12.306, P<0.01) ]. Occupation disease group canal volume average (1.68±0.39) ml higher than that of non occupation disease group (1.57±0.47) ml, the difference was statistically significant (t=2.756, P<0.01) ; occupation disease group mean static compliance (1.06±0.82) ml higher than that of non occupation disease group (0.89±0.64) ml. The difference was statistically singificant (t=2.59, P<0.01) . Conclusion We observed that acoustic impedance test had obvious auxiliary function in the differential diagnosis of occupational noise induced deafness, More than 90% of the confirmed cases showed an A-form tympanograms, it is one of the objective examination methods which can be used in the differential diagnosis of pseudo deafness.

OBJECTIVE: To analyze the impact of GBZ 49-2014 Diagnosis of Occupational Noise-induced Deafness and GBZ49-2007 Diagnostic Criteria of Occupational Noise-induced Deafness on the diagnosis of occupational noise-induced deafness( ONID). METHODS: A total of 84 individuals,who were workers exposed to noise and diagnosed as observation subjects by GBZ 49-2007 were selected as the subjects of study by judgment sampling. They were diagnosed based on the criteria of GBZ 49-2014 and GBZ 49-2007. The impact of different diagnostic audiometry,different age and gender correction methods and the inclusion of a weighting of 0. 1 high-frequency 4. 0 k Hz hearing threshold of GBZ 49-2014 on the diagnosis of ONID was analyzed. RESULTS: The binaural high frequency threshold average( BHFTA) calculated by GBZ 49-2014 were lower than that of GBZ 49-2007 [( 52. 1 ± 10. 3) vs( 52. 8 ± 10. 1) d B,P < 0. 05 ],but monaural threshold of weighted value( MTWV) of the good ear calculated by GBZ 49-2014 were higher than speech frequency threshold average( SPTA) of the good ear of GBZ 49-2007 [( 23. 2 ± 4. 1) vs( 19. 3 ± 4. 8) d B,P < 0. 01]. All of the 84 patients had BHFTA ≥40 d B and SPTA < 26 d B when diagnosed by GBZ 49-2007,and could not be diagnosed as ONID. A total of33. 3% patients had BHFTA ≥40 d B and MTWV ≥26 d B when diagnosed by GBZ 49-2014 which could be diagnosed as mild ONID. The detection rate of ONID was 21. 4% to 34. 5%( P < 0. 01) when the threshold of 4. 0 k Hz was used as the weighting diagnostic threshold of hearing in the case of using different diagnostic audiograms and different age and sex correction methods. CONCLUSION: A high-frequency hearing threshold of 4. 0 k Hz with a weighting of 0. 1 was included in GBZ 49-2014 as a diagnostic threshold,which reduced the diagnostic threshold of ONID.

OBJECTIVE: To analyze the changes of finger skin temperature in cold provocation test( CPT) in workers with vibration white finger( VWF). METHODS: A total of 245 male workers engaged in hand arm vibration operation was selected as study subjects using random number table method. All subjects were divided into VWF group( 73 persons) and control group( 172 persons). CPT( 10 ℃,10 min) was performed and the skin temperature of 6 fingers( index finger,middle finger and ring finger of both hands) was measured at pre-CPT adaptation period( 0,10,20,30 min) and after CPT period( 0,5,10,15,20,25,30 min). RESULTS: The effect of interaction between grouping and observe time was statistically significant on finger skin temperature( P < 0. 01). In the pre-CPT adaptation period,there was no statistically significant difference on skin temperature between 10 and 30 min time point in the two groups( P > 0. 05). After CPT,the fingers skin temperature of VWF group was lower than that of control group at 5 min time point( P < 0. 05),but there were no statistically significant differences on fingers skin temperature of other time points between the two groups( P > 0. 05).In both groups,the finger skin temperature at 0 min time point after CPT were lower than other time points in the same group( P < 0. 05),and the finger skin temperature increased with time( P < 0. 01). However,the finger skin temperature at 30 min after CPT did not restore to that at 30 min time point of pre-CPT. Except the VWF group,the abnormal rewarming temperature at 5 min time point after CPT of left index finger,the right index finger and the right ring finger were higher than that of the control group( 72. 6% vs 56. 4%,75. 3% vs 57. 6%,86. 3% vs 65. 1%,P < 0. 05),but there were no statistically significant differences on the abnormal rewarming temperature at 10,30 min time points of the six fingers in the two groups( P > 0. 05). There were no statistically significant differences on the detection rate of abnormal rewarming temperature between left index finger and the right index finger,or the right index finger and the right ring finger in the VWF group( 72. 6% vs 75. 3%,75. 3% vs 86. 3%,P > 0. 05). CONCLUSION: When CPT( 10 ℃,10 min) was performed in workers engaged in hand arm vibration operation,it is recommended to measure the finger skin temperature of index finger,and adaptation time before CPT can be adjusted to 10 min.

Objective: Study of the results and the degree on occupational noise-induced deafness in-to the different high frequency hearing threshold weighted value, in order to provide theoretical basis for the re-vision of diagnostic criteria on occupational noise-induced deafness. Methods: A retrospective study was con-ducted to investigate the cases on the diagnosis of occupational noise-induced deafness in Guangdong province hospital for occupational disease prevention and treatment from January 2016 to January 2017. Based on the re-sults of the 3 hearing test for each test interval greater than 3 days in the hospital, the best threshold of each frequency was obtained, and based on the diagnostic criteria of occupational noise deafness in 2007 edition, Chi square test, t test and variance analysis were used to measure SPSS21.0 data, their differences are tested among the means of speech frequency and the high frequency weighted value into different age group, noise ex-posure group, and diagnostic classification between different dimensions. Results: 1. There were totally 168 cases in accordance with the study plan, male 154 cases, female 14 cases, the average age was 41.18 ±6.07 years old. 2. The diagnosis rate was increased into the weighted value of different high frequency than the mean value of pure speech frequency, the weighted 4 kHz frequency increased by 13.69% (χ²=9.880, P=0.002) , 6 kHz increased by 15.47% (χ²=9.985, P=0.002) and 4 kHz+6 kHz increased by15.47% (χ²=9.985, P=0.002) , the difference was statistically significant. The diagnostic rate of different high threshold had no obvious differ-ence between the genders. 3. The age groups were divided into less than or equal to 40years old group (A group) and 40-50 years old group (group B) , there were higher the diagnostic rate between high frequency weighted 4 kHz (A group χ²=3.380, P=0.050; B group χ²=4.054, P=0.032) , weighted 6 kHz (A group χ²=6.362, P=0.012; B group χ²=4.054, P=0.032) , high frequency weighted 4 kHz+6 kHz (A group χ²=6.362, P=0.012; B group χ²=4.054, P=0.032) than those of speech frequency average value in the same group on oc-cupational noise-induced deafness diagnosis rate, the difference was statistically significant. There was no sig-nificant difference between age groups (χ²=2.265, P=0.944) . 4. The better ear's mean value of pure speech fre-quency and the weighted values into different high frequency of working years on each group were compared, working years more than 10 years group was significantly higher than that of average thresholds of each frequen-cy band in 3-5 group (F=2.271, P=0.001) , 6-10 group (F=1.563, P=0.046) , the difference was statistically significant. The different high frequency weighted values were higher than those of the mean value of pure speech frequency, and the high frequency weighted 4 kHz+6 kHz had the highest frequency difference, with an average increase of 2.83 dB. 5. The diagnostic rate into weighted different high frequency was higher in the mild, moderate and severe grades than in the pure speech frequency. In the comparison of diagnosis for mild occupational noise-induced deafness, in addition to the weighted 3 kHz high frequency (χ²=3.117, P=0.077) had no significant difference, the weighted 4 kHz (χ²=10.835, P=0.001) , 6 kHz (χ²=9.985, P=0.002) , 3 kHz+4 kHz (χ²=6.315, P=0.012) , 3 kHz+6 kHz (χ²=6.315, P=0.012) , 4 kHz+6 kHz (χ²=9.985, P=0.002) , 3 kHz+4 kHz+6 kHz (χ²=7.667, P=0.002) were significantly higher than the diagnosis rate of the mean value of pure speech frequency. There was no significant difference between the two groups in the moderate and se-vere grades (P>0.05) . Conclusion Bring into different high frequency hearing threshold weighted value in-creases the diagnostic rate of occupational noise-induced deafness, the weighted 4 kHz, 6 kHz and 4 kHz+ 6 kHz high frequency value affects the result greatly, and the weighted 4 kHz+6 kHz high frequency hearing threshold value is maximum the effect on occupational noise-induced deafness diagnosis.

{L-End}Objective To analyze the changes of seven potential biomarkers in plasma of patients with occupational silicosis (hereinafter referred to as "silicosis"), and explore their clinical value in determining the stage of silicosis. {L-End}Methods A total of 100 male silicosis patients were selected as the silicosis group (63 cases in stage Ⅰ and 37 cases in stage Ⅱ subgroups), and 100 male healthy individuals were selected as the control group using the 1∶1 matched case-control study. Enzyme-linked immunosorbent assay was used to analyze the level of interleukin-17 (IL-17), monocyte chemoattractant protein-1 (MCP-1), matrix metalloproteinase-9 (MMP-9), Krebs von den Lungen-6 (KL-6), connective tissue growth factor (CTGF), platelet-derived growth factor (PDGF), and histone H4 in plasma. Their clinical value for diagnosing silicosis was evaluated using receiver operating characteristic (ROC) curve, discriminant analysis stepwise method, and Fisher discriminant function analysis. {L-End}Results The levels of IL-17, MCP-1, MMP-9, KL-6, CTGF, PDGF, and histone H4 in the plasma of the silicosis group, silicosis stage Ⅰ subgroups, and stage Ⅱ subgroups were higher than those in the control group (all P<0.05). The levels of IL-17, MCP-1, and MMP-9 in the plasma of the stage Ⅱ subgroup decreased (all P<0.05), while the levels of KL-6, CTGF and histone H4 increased (all P<0.05) compared with the stage Ⅰ subgroup. The area under the ROC curve for diagnosing silicosis using these seven potential biomarkers ranged from 0.761 to 1.000 (all P<0.01), with the sensitivity of 0.640-1.000, the specificity of 0.840-0.990, and the Youden index of 0.540-0.990. The Fisher discriminant function was formed by stepwise discriminant analysis, and the results showed that the coincidence rate was 99.5%, and the misdiagnosis rate was 0.5% for diagnosing and staging silicosis with these seven potential biomarkers. The coincidence rate of diagnosing control group, silicosis stageⅠsubgroup and the silicosis stage Ⅱ subgroup was 100.0%, 98.4% and 100.0%, respectively. {L-End}Conclusion IL-17, MCP-1, MMP-9, KL-6, CTGF, PDGF and histone H4 in plasma can be used as biomarkers for the diagnosis of silicosis, and the Fisher discriminant function based on the combination of these seven biomarkers can assist in staging silicosis.

Objective To establish a set of scientific and standardized quality control indicator system for occupational pneumoconiosis (hereinafter referred to as "pneumoconiosis") medical care. Methods A research group was set up to establish an indicator pool of quality control indicator system for pneumoconiosis, including three first-level indicators and 48 second-level indicators, based on literature review, analysis and sorting, and the current national quality control indicators of respiratory diseases in disease-specific quality monitoring. Two rounds of consultation were conducted with 15 experts through Delphi method to establish the quality control indicator system for pneumoconiosis medical care. Results The questionnaire recovery rates of the two rounds of expert consultations were 100%, and the effective questionnaire recovery rates of both consultations were 100%. The expert authority coefficient was 0.91, and the expert coordination coefficients were 0.208 and 0.209, respectively (both P<0.001). The coefficient of variation ranged from 0.10 to 0.37, with nine indicators having a coefficient of variation >0.25. The constructed quality control indicator system for pneumoconiosis medical care includes three primary indicators, 15 secondary indicators, and 32 tertiary indicators. Conclusion The constructed quality management indicator system for pneumoconiosis medical care has high scientificity and reliability. It provides a basis for the quality evaluation of pneumoconiosis medical care. However, continuous improvement is needed in practical applications.

Objective To analyze the epidemiological characteristics and related occupational diagnosis situations of occupational heat illness (OHI) diagnosed by Guangdong Province Hospital for Occupational Disease Prevention and Treatment (GDHOD) from 2011 to 2022. Methods A total of 203 patients who applied for OHI diagnosed in GDHOD from 2011 to 2022 were recruited as research subjects using the retrospective analysis method. Clinical data of OHI diagnosed cases was collected from "Occupational Diseases and Hazards Monitoring Information System" under "China Disease Prevention and Control Information System", and data of cases that diagnosed as non-OHI were collected from the occupational disease diagnosis file of GDHOD for retrospective analysis. Resultsi) The number of OHI diagnosed patients was 174 among 203 cases, with a rate of 85.7%. ii) The heat stroke accounted for 72.4% with a mortality rate of 7.5%, male patients accounted for 86.2% among the 174 OHI diagnosed cases. The median age of onset was 47 years, and patients aged 45-60 years accounting for 56.3%. The median working period of onset of illness was 80 days, with 20.1%, 40.8%, 53.4% and 70.1% of cases occurring within 1, 30, 90 and 365 days of working, respectively. The patients were concentrated in the Pearl River Delta region, accounting for 93.1%. The peak incidence of OHI occurred from May to September, accounted for 96.6%, with the highest incidence occurred in July. About 67.3% of cases occurred on days when the maximum temperature was ≥35.0 ℃. Cases occurred between 12:00 and 18:00 accounting for 74.1%, and cases occurred within 8 hours of work accounting for 75.2%. OHI of patients occurred during operations in non-heat-source workshops accounted for 43.7% of cases, while outdoor operations accounted for 39.7%. OHI patients in manufacturing and small private enterprises accounted for 55.2% and 62.6%, and the main occupations were workshop operators, loaders/unloaders, and sanitation workers, comprising 63.2% of cases. iii) Among the 29 cases diagnosed as non-OHI, accounting for 86.2% patients with high-temperature work history who did not meet clinical diagnostic criteria, most of them were diagnosed as OHI precursor. Conclusion OHI patients in Guangdong Province predominantly occur in summer and autumn, with heat stroke being the primary condition. Middle-aged males, workers in non-heat-source workshops and outdoor settings have higher risk of OHI. OHI cases are concentrated in specific region and enterprise. The OHI prevention should be enhanced on high-risk workers, who work in the Pearl River Delta region, manufacturing, and small private enterprises.

OBJECTIVE: To investigate the individual external dose level of medical radiation staffs in Guangzhou City.METHODS: The medical radiation staffs of Guangzhou City who conducted individual dose monitoring at Guangdong Province Hospital Center for Occupational Diseases Prevention and Treatment from 2008 to 2014 were selected as study subjects by convenient sampling method.Their individual dosage monitoring data were analyzed.RESULTS: A total of 17 754 person-times were monitored in 7 years.The annual collective effective dose was 10 621.1 person·mSv and the median per capita annual effective dose was 0.21 mSv/a.The per capita annual effective dose in 2008-2012 showed an increasing trend each year( P < 0.05),peaked in 2012,and then decreased in 2013 and 2014( P < 0.05).The per capita annual effective dose of radiology staffs in level Ⅱ medical institutions was higher than that of level Ⅲ medical institutions,level Ⅰ medical institutions and those below level Ⅰ( P < 0.01).The per capita annual effective dose of radiation staffs in level Ⅲ medical institutions was higher than level Ⅰ medical institutions and those below level Ⅰ( P <0.01).The effective monitoring rates of radiation staffs monitored for 4 cycles every year increased with time from 2008 to 2014( P < 0.01).The effective monitoring rate increased with the hospital level( P < 0.01).The per capita annual effective dose of the staffs in radiological diagnosis department was lower than that of clinical nuclear medicine,radiotherapy and interventional radiology( P < 0.01).CONCLUSION: The radiation dose of medical radiation staffs in Guangzhou City was within the national standard limit.Protection should be focused on the the staffs in secondary hospitals,clinical nuclear medicine,radiotherapy and interventional radiology.

OBJECTIVE: To investigate the effects of subacute systemic inhalation exposure of 1,2-dichloroethane(1,2-DCE) on learning and memory in NIH mice. METHODS: Forty-five specific pathogen free healthy 7-week-old NIH mice were randomly divided into control,low-dose and high-dose groups with 5 female mice and 10 male mice in each group. The mice were exposed to 1,2-DCE at dosages of 0. 00,100. 00 and 350. 00 mg/m3 for 6 hours per day for consecutive 28 days by dynamic systemic inhalation. The neurobehavioral tests of mice were performed before and after the first to fourth weeks of exposure using the Morris water maze test. RESULTS: There was no significant difference in body weight and swimming speed among the three groups of mice( P > 0. 05). The navigation experiment results showed that the escape latency of mice in both low-and high-dose groups were longer than that of the control group at the same time point(P < 0. 05) during 1-4 weeks after exposure. In the control group,the escape latency was shorter than that of the same group before exposure( P < 0. 05). The escape latency of high-dose group prolonged with the increase of exposure time,and in the 4 th week the escape latency was significantly higher than that of the same group before exposure( P < 0. 05).The experiment results of space exploration indicated that the first time of crossing platform in low-and high-dose groups were longer than that of the control group at the second to the fourth week( P < 0. 05). The target quadrant retention time and the number of crossing the platform in the low-and high-dose groups were lower than those in the control group( P <0. 05). CONCLUSION: Subacute inhalation exposure of 1,2-DCE can impair the learning and memory ability of NIH mice.The high-dose exposure may reduce learning ability in mice in a time-effect manner.

OBJECTIVE: To explore the association of interaction of noise exposure and superoxide dismutase( SOD) gene polymorphism on the susceptibility of occupational noise-induced hearing loss( ONHL) in Chinese Han population.METHODS: A simple random sampling method was used to select 2 400 Han workers as study subjects.These workers were exposed to 75.0-120.0 dB( A) of normalized continuous A-weighted sound with pressure level equivalent to a 40 hworking-week( L_(EX,W)) in Guangzhou City.A model method was set up to define 201 sensitive workers( sensitive group)and 202 resistant workers( resistant group) by combining results with hearing pure tone threshold test and the cumulative noise exposure( CNE).The genomic DNA was extracted from peripheral blood cells.The single nucleotide polymorphisms analysis of SOD was carried out by using the TaqMan probe with chemical fluorescence allelic identification test.Binary logistic regression method was used to analyze the interaction of noise exposure and SOD.RESULTS: After adjusting confounding factors such as gender,heavy metal exposure,dust exposure and high temperature exposure,the risk for ONHL in individuals interactively carry rs2040724 AG or GG and rs4880( CC + CT) was significantly higher than that in individuals interactively carry rs2040724 AA and rs4880 TT( P < 0.05).The risk for ONHL in individuals interactively carry rs10432782 GT or GG and rs4880( CC + CT) was significantly higher than that in individuals interactively carry rs10432782 TT and rs4880 TT( P < 0.05).The risk for ONHL in individuals exposed to L_(EX,W)≥85 dB( A) and interactively carried with rs2040724 GG and rs4880( CC + CT) was significantly higher than that in individuals exposed to L_(EX,W)< 85 dB( A) and interactively carry rs2040724 AA and rs4880 TT( P < 0.01).The risk for ONHL in individuals exposed to L_(EX,W)≥85 dB( A) and interactively carry rs10432782 GT or GG and rs4880( CC + CT) was significantly higher than that in individuals exposed to L_(EX,W)< 85 dB( A) and interactively carry r10432782 TT and rs4880 TT( P < 0.05).CONCLUSION: In Chinese Han population,noise exposure intensity and SOD1( rs2040724,rs10432782),SOD2( rs4880)gene polymorphism had interacting effects on ONHL susceptibility.