Objective To explore the application value of anhydrous ethanol as an alternative to methanol in the preparation of chromosomal specimens from peripheral blood lymphocytes, and to establish a set of quantitative analytical methods for objectively evaluating the effectiveness of specimen preparation. Methods Residual blood samples from routine laboratory slide preparation were used for lymphocyte culture. The standard slide preparation method was employed. The fixative in the control group was methanol and glacial acetic acid (3∶1). Four experimental groups were set up based on the ratio of anhydrous ethanol to glacial acetic acid in the fixative (volume ratios of 3∶1, 5∶1, 7∶1, and 9∶1 for experimental groups 1, 2, 3, and 4, respectively). A chromosomal analysis was conducted using an automated chromosome scanning/image analysis system to evaluate the morphology and dispersion of metaphase chromosomes in both control and experimental groups. Comparisons were made between the control and experimental groups regarding the dic + r aberration rate, ace aberration rate, chromosomal aberration rate, chromosome dispersion index, chromosome overlapping ratio, and dispersion index/overlapping ratio. Results Microscopic evaluation revealed that the preparation quality of experimental groups 1 and 2 was comparable to the control group. No statistically significant differences were observed in dic + r aberration rate between each of the experimental groups and the control (P > 0.05). All experimental groups except group 4 showed no significant differences in ace aberration rate and chromosome aberration rate compared with the control group (P > 0.05). Experimental groups 1 and 2 showed no significant differences in chromosome dispersion index, overlapping ratio, and dispersion index/overlapping ratio compared with the control group (P > 0.05). Conclusion A mixture of anhydrous ethanol and glacial acetic acid at a 5∶1 ratio is recommended for use as a fixative in the preparation of chromosomal specimens from peripheral blood lymphocytes. A quantitative index system for assessing the quality of chromosomal specimens was established, enabling objective evaluation of slide preparation effectiveness.

OBJECTIVE: To explore the application value of computer-aided diagnosis technology based on deep residual network in the diagnosis of occupational pneumoconiosis(hereinafter referred to as pneumoconiosis). METHODS: A total of 5 424 digital radiography chest images were collected from occupational health examiners using a convenient sampling method.These images were used to establish a data set. After training with the data set, the pneumoconiosis computer-aided diagnosis system was used to independently diagnose the test set images(50 positive and negative cases each) and output a positive probability value. Six diagnostic physicians with varied ages and different experiences performed independent diagnosis on the test set and assisted diagnosis with reference to computer results. The diagnostic accuracy was evaluated using the area under the receiver operating characteristic curve(AUC) value, sensitivity, and specificity.The Kappa consistency test was used to evaluate the diagnostic consistency. RESULTS: The AUC value, sensitivity, specificity, and Kappa value of pneumoconiosis diagnosis increased after using computer-aided diagnosis. The sensitivity increased from 0.74 to 0.85(P<0.05)and the Kappa value increased from 0.64 to 0.79(P<0.05). The AUC value increased from 0.90 to 0.95, and the specificity increased from 0.89 to 0.94, but there were no statistical difference(P<0.05). CONCLUSION: Computer-aided diagnosis can improve the sensitivity and consistency of pneumoconiosis screening and reduce the differences in diagnosis among physicians.

Objective: To investigate hearing loss status of blasters, drillers mechanics and so on in underground mining, and put forward suggestion diagnosis of occupational explosive deafness and occupational deafness. Methods: Underground excavation workers in a metal mine were recruited in this study, those with a history of ear disease and non-occupational deafness were all excluded. Finally, the features of pure tone audiometry of 459 noise-exposed workers were analyzed. Results: High-frequency hearing loss occurred on 351workers and the positive detection rate was 74.29%, workers who had both high-frequency and linguistic frequency hearing loss were 51 and the positive detection rate was 11.11%. The positive detection of high-frequency hearing loss in right ear (χ²=9.427 and P= 0.024) and in left ear (χ²=14.375, P=0.002) was significantly different between different exposure age groups. The positive detection of high-frequency hearing loss of driving group was the highest, followed by blasting group, mining group and machine repair group. The characteristics of the hearing loss caused by drilling noise of the blasting workers with no accident occurred were in line with that of noise-induced hearing loss. Conclusion The diagnosis grading should be carried out according to the diagnostic criteria of occupational noise-induced deafness for the employees who engaged in the blasting operation with no record of blast accident.