Objective To investigate the characteristics of click -auditory brainstem response (ABR) in nor-mal infants of 1 to 6 months old ,and to establish the normative values for latencies of Wave I ,III ,V and interpeak latencies of I- Ⅲ ,III-V and I-V for younger infants .Methods Click auditory brainstem responses were recorded from infants within 6 months :166 infants of 1 -months old(269 ears) ,141 2 -month old (226 ears) ,111 3 -months old(177 ears) ,58 4-months old(96 ears) ,78 5-months old(121 ears) and 45 6-months old(76 ears) .We compared the latencies of wave I ,III ,V and interpeak latencies of I - Ⅲ ,III-V ,I-V obtained from infants of differ-ent ages at different stimulus intensities .Results The average threshold of 1 to 6 months infants was 16 .18 ± 5 .35 dB nHL ,the average latency of Wave V was 9 .03 ± 0 .49 ms .The differences among the thresholds were statistical-ly insignificant(P>0 .05) .Wave I ,III and V were noticeable in all ears tested at 80 dB nHL .Wave I disappeared first as the stimulus intensity decreased ,and the latencies of Wave I ,III and V prolonged;on the contrary ,interpeak latencies of I -III ,III-V ,I-V shortened significantly .At the same stimulus intensity ,the latencies of Wave III , V and the interpeak latencies of I - Ⅲ ,III-V ,I-V shortened significantly except for Wave I .When comparing the differences among the testing parameters as a function of each month ,we found that there were statistically signifi-cant differences for the latencies of wave III ,V and the interpeak latencies of I -III ,III-V ,I-V before the 4 months old(P<0 .05) ,and there were no significant differences after 4 months old(P>0 .05) .Conclusion It is recommen-ded that 16 .18 ± 5 .35 dB nHL be used as the normative references for the evoked threshold of click auditory brain-stem responses for 1~6 month old infants .The development of central nervous system below the inferior calicles is fast before the 4 months old .

Objective To explore the effects of different probe tone and tympanometric admittance measure-ment methods on the diagnose of otitis media prediction ,and to provide a clinical reference for the selection of probe tones and measurement method to apply to newborn infants .Methods Tympanograms with 226 Hz and 1 000 Hz probe tones were obtained from normal infants (142 ears) and infants with otitis media (90 ears) .Mean values , standard deviations ,the 90% range and 95% mean confidence interval were recorded as the variable to observe po-tential impacts on tympanometric admittance with 226 Hz probe tone and tympanometric peak admittance with 1 000 Hz probe tone by three different measurement methods respectively according to Linder/Jerger classification ,the Baldwin classification and baseline classification adapted from Baldwin .The four indexes were tested with compara-tive analysis .The area under ROC curve simultaneous detects the normal group and otitis media group ,with refer-ences to the accuracy of the detection method to disease (including specificity and sensitivity ) .Results In 1-to -3 month group ,tympanometric admittance with 226 Hz probe tone and tympanometric peak admittance with 1 000 Hz probe tone by three different measurement methods were 0 .83 ± 0 .29 ,0 .60 ± 0 .55 ,0 .74 ± 0 .56 ,0 .90 ± 0 .59 in nom-al infants and 0 .82 ± 0 .35 ,0 .01 ± 0 .06 ,-0 .24 ± 0 .15 ,-0 .29 ± 0 .21 in infants with OME ,respectively .The areas under ROC curve of the four kinds of measurement methods were 0 .507 ,0 .896 ,0 .976 ,0 .988 ,respectively .In 4 to 6 month group ,tympanometric admittance with 226 Hz probe tone and tympanometric peak admittance with 1 000 Hz probe tone by three different measurement methods were 0 .60 ± 0 .35 ,0 .55 ± 0 .58 ,0 .76 ± 1 .0 ,0 .86 ± 0 .72 in nomal infants and 0 .36 ± 0 .24 ,0 ± 0 ,-0 .34 ± 0 .16 ,-0 .44 ± 0 .28 in infants with OME ,respectively .The areas under ROC curve of the four kinds of measurement methods were 0 .749 ,0 .888 ,0 .969 ,0 .988 in 4 to 6 month infants ,re-spectively .Tympanometric peak admittance with 1 000 Hz probe tone by three different measurement methods were significantly better than that with 226 Hz probe tone .The areas under ROC curve of tympanometric peak admittance with 1 000 Hz probe tone by baseline classification adapted from Baldwin were bigger than others and the differences were significant(P<0 .05) ,but no difference between the Baldwin classification and baseline classification in 4 to 6 month infants(P>0 .05) .Conclusion Tympanometric peak admittance with 1 000 Hz probe tone were better than that with 226 Hz probe tone to assess otitis media in 1~6 month infants .The baseline classification adapted from Baldwin was appropriate for the measurement of tympanometric peak admittance with 1 000 Hz probe tone .

Objective:To provide scientific evidence for the prevention and control strategies of noise-induced deafness, to analyze the epidemiological characteristics of the occupational noise-induced deafness diagnostic applicants in Guangzhou city during 2011-2018.Methods:In March 2019, by consulting the occupational disease diagnosis records, we investigated the distribution of all 471 occupational noise-induced deafness diagnostic applicants in Guangzhou Occupational Disease Prevention and Treatment Center from 2011 to 2018. Frequency and constituent ratio were used to describe the distribution.Results:From 2011 to 2018, there were 471 cases of occupational noise-induced deafness diagnostic applicants and 211 of the applicants were diagnosed as occupational noise-induced deafness (44.8%, 211/471) . The new cases were mainly mild (83.9%, 177/211) , with the predilection age of 40.0-49.0 years old (41.7%, 88/211) and the predilection seniority of 5.0-9.9 years (38.9%, 82/211) . Among the new cases, there were mainly males (88.6%, 187/211) . Most of the new cases were distributed in Nansha district (23.2%, 49/211) , Huangpu district (22.7%, 48/211) and Panyu district (21.8%, 46/211) . Besides, in terms of industry distribution, they were concentrated in manufacturing industry (82.0%, 173/211) . The scale of enterprises was mainly medium-sized (42.7%, 90/211) , and the most of their economic type was domestic-funded (40.8%, 86/211) .Conclusion:Although most of the newly diagnosed cases of occupational noise deafness in Guangzhou are mild, they still need to be paid attention to and strengthen the noise industry protection education.

Objective:To describe the characteristics and the survival status of pneumoconiosis cases reported in Guangzhou City from 1958 to 2018, and to investigate the epidemiological trends of pneumoconiosis. This study is aiming to provide basic data for formulating the guidelines and policies for control of pneumoconiosis, and for evaluating the control effects of pneumoconiosis.Methods:From July 2019 to January 2020, based on the data collected in the pneumoconiosis case cards and database as well as the retrospective follow-up investigate of pneumoconiosis cases, we conducted a descriptive analysis for all the new cases of pneumoconiosis reported from 1958 to 2018 in Guangzhou City. The statistical indices included the number of new pneumoconiosis cases in each decade, types of pneumoconiosis, regional and industrial distributions, survival status, and the change tendency of the diagnosis age and the dust exposure time of pneumoconiosis cases.Results:From 1958 to 2018, a total of 1194 new cases of pneumoconiosis were reported in Guangzhou City, including 1147 males (96.1%) and 47 females (3.9%) . Silicosis (60.1%, 718/1194) and welder's pneumoconiosis (21.5%, 257/1194) were the main types of pneumoconiosis. The top three districts for reporting new cases were Huangpu District (29.0%, 346/1194) , Nansha District (12.6%, 151/1194) and Baiyun District (11.1%, 132/1194) , respectively. The top three industries for reporting new cases were civil engineering construction industry (25.0%, 298/1194) , railway ship aerospace and other transportation equipment manufacturing industry (16.1%, 192/1194) and non-metal mining industry (15.7%, 187/1194) . The diagnosis age for new cases was 47.8 (23.6-79.1) years old, and the dust exposure time was 12.3 (0.4-49.1) years. Both of these two statistical indicators rose first and fell later from 1958 to 2018. As of December 31, 2019, a total of 963 new cases of pneumoconiosis were followed up, of which 467 (48.5%) survived, mainly silicosis (41.3%, 193/467) and welder's pneumoconiosis (43.3%, 203/467) . 496 cases (51.5%) died, and the age of death was 69.9 (32.4-96.9) years old.Conclusion:According to the epidemiological characteristics of pneumoconiosis in Guangzhou, we should focus on key districts and industries in the prevention and control of pneumoconiosis. Besides, the staffs in the occupational disease diagnosis institutions should try the best to collect the complete dust exposure data of new cases of pneumoconiosis. Moreover, the health administrative departments should pay more attention to the management of pneumoconiosis death case reports.

Objective:To provide scientific evidence for the prevention and control strategies of noise-induced deafness, to analyze the epidemiological characteristics of the occupational noise-induced deafness diagnostic applicants in Guangzhou city during 2011-2018.Methods:In March 2019, by consulting the occupational disease diagnosis records, we investigated the distribution of all 471 occupational noise-induced deafness diagnostic applicants in Guangzhou Occupational Disease Prevention and Treatment Center from 2011 to 2018. Frequency and constituent ratio were used to describe the distribution.Results:From 2011 to 2018, there were 471 cases of occupational noise-induced deafness diagnostic applicants and 211 of the applicants were diagnosed as occupational noise-induced deafness (44.8%, 211/471) . The new cases were mainly mild (83.9%, 177/211) , with the predilection age of 40.0-49.0 years old (41.7%, 88/211) and the predilection seniority of 5.0-9.9 years (38.9%, 82/211) . Among the new cases, there were mainly males (88.6%, 187/211) . Most of the new cases were distributed in Nansha district (23.2%, 49/211) , Huangpu district (22.7%, 48/211) and Panyu district (21.8%, 46/211) . Besides, in terms of industry distribution, they were concentrated in manufacturing industry (82.0%, 173/211) . The scale of enterprises was mainly medium-sized (42.7%, 90/211) , and the most of their economic type was domestic-funded (40.8%, 86/211) .Conclusion:Although most of the newly diagnosed cases of occupational noise deafness in Guangzhou are mild, they still need to be paid attention to and strengthen the noise industry protection education.

Objective:To describe the characteristics and the survival status of pneumoconiosis cases reported in Guangzhou City from 1958 to 2018, and to investigate the epidemiological trends of pneumoconiosis. This study is aiming to provide basic data for formulating the guidelines and policies for control of pneumoconiosis, and for evaluating the control effects of pneumoconiosis.Methods:From July 2019 to January 2020, based on the data collected in the pneumoconiosis case cards and database as well as the retrospective follow-up investigate of pneumoconiosis cases, we conducted a descriptive analysis for all the new cases of pneumoconiosis reported from 1958 to 2018 in Guangzhou City. The statistical indices included the number of new pneumoconiosis cases in each decade, types of pneumoconiosis, regional and industrial distributions, survival status, and the change tendency of the diagnosis age and the dust exposure time of pneumoconiosis cases.Results:From 1958 to 2018, a total of 1194 new cases of pneumoconiosis were reported in Guangzhou City, including 1147 males (96.1%) and 47 females (3.9%) . Silicosis (60.1%, 718/1194) and welder's pneumoconiosis (21.5%, 257/1194) were the main types of pneumoconiosis. The top three districts for reporting new cases were Huangpu District (29.0%, 346/1194) , Nansha District (12.6%, 151/1194) and Baiyun District (11.1%, 132/1194) , respectively. The top three industries for reporting new cases were civil engineering construction industry (25.0%, 298/1194) , railway ship aerospace and other transportation equipment manufacturing industry (16.1%, 192/1194) and non-metal mining industry (15.7%, 187/1194) . The diagnosis age for new cases was 47.8 (23.6-79.1) years old, and the dust exposure time was 12.3 (0.4-49.1) years. Both of these two statistical indicators rose first and fell later from 1958 to 2018. As of December 31, 2019, a total of 963 new cases of pneumoconiosis were followed up, of which 467 (48.5%) survived, mainly silicosis (41.3%, 193/467) and welder's pneumoconiosis (43.3%, 203/467) . 496 cases (51.5%) died, and the age of death was 69.9 (32.4-96.9) years old.Conclusion:According to the epidemiological characteristics of pneumoconiosis in Guangzhou, we should focus on key districts and industries in the prevention and control of pneumoconiosis. Besides, the staffs in the occupational disease diagnosis institutions should try the best to collect the complete dust exposure data of new cases of pneumoconiosis. Moreover, the health administrative departments should pay more attention to the management of pneumoconiosis death case reports.

OBJECTIVE: To analyze the judgement standard and evaluate the diagnostic value of the low frequency and high frequency tympanometry in infants with otitis media. METHOD: Tympanograms for admittance with 226 Hz and 1 000 Hz probe tones and resonant frequency were obtained from normal infants (195 cases, 321 ears) and infants with otitis media(122 cases, 171 ears). The mean, standard deviation, median, 5% quantile, 95% quantile and 95% confidence interval of peak admittance, gradient and resonant frequency were measured and calculated in different age groups. The significant differences of 1000 Hz peak admittance, 226 Hz peak admittance and gradient between normal infants and infants with otitis median were analyzed using SPSS 11.0. The false positive rate and the false negative rate of different age groups in infants with otitis media were evaluated according to such judgement standards as 1000 Hz peak admittance, 226Hz peak admittance or gradient. RESULT: The false positive rate and the false negative rate of the 1000 Hz probe tone tympanometry in infants with otitis media unter one year of age were 3.07% and 1.84% as the normal range of positive peak was more than 0.2 mmho. The false positive rate and the false negative rate of the 1000 Hz probe tone tympanometry in infants with otitis media aged 1-2 years and aged 2-3 years were 3.26%, 5.26% and 1.52%, 0.00% respectively,as the normal range of positive peak was more than 0.3 mmho. These was no significant difference in the gradient with 226 Hz probe tone between normal infants and infants with otitis median under one year of age. The false positive rate and the false negative rate of the 226 Hz probe tone tympanometry in infants with otitis media aged 1-2 years and aged 2-3 years were 44.57%, 31.58% and 16.67%, 6.67% respectively, as the gradient with 226 Hz probe tone was a judgement standard. CONCLUSION (1) The diagnostic accuracy of tympanometry with 1000 Hz probe tone for otitis media in infants younger than 3 years of age exceeded 226 Hz probe tone tympanometry, the 1000 Hz probe tone tympanometry is suggested to the evaluation of middle ear function in infants before 3 years. (2) It is reasonable that the normal range of positive peak is more than 0.2 mmho in infants unter one year of age and the normal range of positive peak is more than 0.3 mmho in infants aged 1-3 years.
Acoustic Impedance Tests ; methods ; statistics & numerical data ; Case-Control Studies ; Humans ; Infant ; Infant, Newborn ; Otitis Media ; diagnosis ; Reference Values

Objective:To analyze the survival of pneumoconiosis patients in Guangzhou from 1958 to 2018, explore the factors affecting the survival of pneumoconiosis, and provide scientific basis for formulating the guidelines and policies for treatment and assistance of pneumoconiosis.Methods:From July 2019 to January 2020, 1194 cases of occupational pneumoconiosis patients diagnosed by institutions qualified for pneumoconiosis diagnosis in Guangzhou from June 1, 1958 to December 31, 2018 were studied. Excluding 258 patients who lacked survival data, 936 patients were included in the pneumoconiosis survival analysis. Life table method was used to estimate the survival rate, Kaplan-Meier method was used to draw the survival curve, log-rank test was used to compare the groups, and Cox proportional risk regression model was used to analyze the influencing factors of survival.Results:The 10, 20 and 30 years cumulative survival rates of pneumoconiosis patients in Guangzhou were 62.8%, 35.2% and 15.4%, respectively. The median survival time was 19.4 years. log-rank test showed that there were statistically significant differences in the survival curves of pneumoconiosis patients between group without tuberculosis and group with tuberculosis ( P<0.001), and there were statistically significant differences among different stages and categories of pneumoconiosis ( P<0.001). Age of exposure to dust ( HR=1.03, 95% CI: 1.01-1.05), age of diagnosis ( HR=1.02, 95% CI: 1.00-1.04), combined pulmonary tuberculosis ( HR=1.46, 95% CI: 1.18-1.81), stage of pneumoconiosis (stage Ⅲ vs. stage Ⅰ, HR=2.26, 95% CI: 1.47-3.48) and categories of pneumoconiosis (fibrogenic mineral dust pneumoconiosis and metallogenic pneumoconiosis, HR=2.45, 95% CI: 1.61-3.74; non-fibrogenic mineral pneumoconiosis and metallogenic pneumoconiosis, HR=2.67, 95% CI: 1.47-4.87; mixed pneumoconiosis and metallogenic pneumoconiosis, HR=2.25, 95% CI: 1.11-4.56) were the factors affecting the survival time of pneumoconiosis patients ( P<0.05) . Conclusion:Pulmonary tuberculosis may increase the risk of death in patients with pneumoconiosis. Mineral dust pneumoconiosis, mixed pneumoconiosis and stage Ⅲ pneumoconiosis may also have higher risk of death.

Objective:To analyze the survival of pneumoconiosis patients in Guangzhou from 1958 to 2018, explore the factors affecting the survival of pneumoconiosis, and provide scientific basis for formulating the guidelines and policies for treatment and assistance of pneumoconiosis.Methods:From July 2019 to January 2020, 1194 cases of occupational pneumoconiosis patients diagnosed by institutions qualified for pneumoconiosis diagnosis in Guangzhou from June 1, 1958 to December 31, 2018 were studied. Excluding 258 patients who lacked survival data, 936 patients were included in the pneumoconiosis survival analysis. Life table method was used to estimate the survival rate, Kaplan-Meier method was used to draw the survival curve, log-rank test was used to compare the groups, and Cox proportional risk regression model was used to analyze the influencing factors of survival.Results:The 10, 20 and 30 years cumulative survival rates of pneumoconiosis patients in Guangzhou were 62.8%, 35.2% and 15.4%, respectively. The median survival time was 19.4 years. log-rank test showed that there were statistically significant differences in the survival curves of pneumoconiosis patients between group without tuberculosis and group with tuberculosis ( P<0.001), and there were statistically significant differences among different stages and categories of pneumoconiosis ( P<0.001). Age of exposure to dust ( HR=1.03, 95% CI: 1.01-1.05), age of diagnosis ( HR=1.02, 95% CI: 1.00-1.04), combined pulmonary tuberculosis ( HR=1.46, 95% CI: 1.18-1.81), stage of pneumoconiosis (stage Ⅲ vs. stage Ⅰ, HR=2.26, 95% CI: 1.47-3.48) and categories of pneumoconiosis (fibrogenic mineral dust pneumoconiosis and metallogenic pneumoconiosis, HR=2.45, 95% CI: 1.61-3.74; non-fibrogenic mineral pneumoconiosis and metallogenic pneumoconiosis, HR=2.67, 95% CI: 1.47-4.87; mixed pneumoconiosis and metallogenic pneumoconiosis, HR=2.25, 95% CI: 1.11-4.56) were the factors affecting the survival time of pneumoconiosis patients ( P<0.05) . Conclusion:Pulmonary tuberculosis may increase the risk of death in patients with pneumoconiosis. Mineral dust pneumoconiosis, mixed pneumoconiosis and stage Ⅲ pneumoconiosis may also have higher risk of death.

Rift Valley fever (RVF) is an acute, febrile zoonotic disease that is caused by the RVF virus (RVFV). RVF is mainly prevalent on the Arabian Peninsula, the African continent, and several islands in the Indian Ocean near southeast Africa. RVFV has been classified by the World Organisation for Animal Health (OIE) as a category A pathogen. To avoid biological safety concerns associated with use of the pathogen in RVFV neutralization assays, the present study investigated and established an RVFV pseudovirus-based neutralization assay. This study used the human immunodeficiency virus (HIV) lentiviral packaging system and RVFV structural proteins to successfully construct RVFV pseudoviruses. Electron microscopy observation and western blotting indicated that the size, structure, and shape of the packaged pseudoviruses were notably similar to those of HIV lentiviral vectors. Infection inhibition assay results showed that an antibody against RVFV inhibited the infective ability of the RVFV pseudoviruses, and an antibody neutralization assay for RVFV detection was then established. This study has successfully established a neutralization assay based on RVFV pseudoviruses and demonstrated that this method can be used to effectively evaluate antibody neutralization.
Africa ; Animals ; Blotting, Western ; HIV ; Indian Ocean ; Islands ; Methods ; Microscopy, Electron ; Product Packaging ; Rift Valley fever virus ; Rift Valley Fever ; Zoonoses