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Objective To study the characteristics of noise hazards in automobile sand casting industry and understand the impact of noise on the health of automobile foundry workers, and to provide scientific data support for the control of noise hazards. Methods An automobile sand casting enterprise was selected as the research object. The post noise intensity test results from 2010 to 2019, the noise spectrum test results of each post in 2019, and the prevalence of occupational noise deafness in the 10 years from 2010 to 2019 were analyzed and sorted out. Using chi-square test and t-test the noise hazard characteristics and noise intensity changes were statistically analyzed. Results 1. The noise LEX.8h exceeding standard rate of foundry enterprises in the 10 years from 2010 to 2019 was not statistically significant（χ2=6.76, P=0.66), and the mean value of noise LEX.8h fluctuated horizontally in the 10 years, which was basically stable between 80 - 90 dB (A). 2. The mean value of noise intensity of sand falling, sand preparation, cleaning and shot blasting in the first five years was significantly different compared to that in the last five years. There was no statistically significant difference in other posts. 3. Among all posts in the foundry sand casting industry, the noise spectrum of core-making and cleaning posts was mainly medium and high frequency, while the noise spectrum of other posts was mainly medium and low frequency. 4, Cases of occupational noise deafness were mainly concentrated in cleaning and polishing workers, melting chemical workers, inspectors and other types of workers. Conclusions The noise hazards in the automobile foundry sand casting industry are mainly concentrated on the posts of molding, and sand falling, and the noise intensity and the over standard rate remain high in the past 10 years. The noise of each post is mainly medium and low frequency, and the noise of a few individual posts is mainly medium and high frequency. In recent years, due to the automatic renewal of equipment, the noise intensity of some posts such as sand dropping, sand mixing, cleaning and shot blasting has decreased, but the overall noise exceeding standard rate has basically not changed, and the noise hazard is still serious. The noise hazard of foundry sand casting enterprises is difficult to be controlled, and the risk of hearing loss of foundry workers is still high.
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Objective@#To explore the incidence regularity and characteristics of pneumoconiosis among migrant workers in Shiyan city, and to provide a basis for making policies about pneumoconiosis prevention and treatment among migrant workers.@*Methods@#In September 2018, 338 cases of pneumoconiosis among migrant workers and 354 cases of pneumoconiosis among non-migrant workers were collected between 2013 and 2017. The proportions of pneumoconiosis types, the age and seniority of onset workers, the severity grade of pneumoconiosis, the type of pneumoconiosis, the type of work and regional distribution, etc. were analyzed.@*Results@#The age at onset of pneumoconiosisand the length of service of migrant workers and non-migrant workers in Shiyan city were significantly different (t=2.237, 3.208, P<0.05) . The proportion of pneumoconiosis stage was significantly different from that of non-migrant workers (χ2=47.897, P<0.05) , among migrant workers, the types of pneumoconiosis were mainly silicosis (308 cases, 91.1%) , coal worker's pneumoconiosis (29 cases, 8.6%) . The leading work types are rock drilling (115 cases, 34.0%) and blasting (105 cases, 31.1%) . The industry was mainly engaged in non-ferrous metal mining (205 cases, 60.7%) and coal (105 cases, 31.1%) . The area distribution involved each counties of Shiyan city, with Zhushan county (175 cases, 51.8%) and Yunxi county (125 cases, 37.0%) as the top two districts in number of cases. Of the cases of migrant workers, 89 cases (26.3%) had blood relationship with any others. There was no work-related injury insurance for migrant workers with pneumoconiosis.@*Conclusion@#There is a high incidence of pneumoconiosis among migrant workers in Shiyan city, featured with the phenomenon of "late occurrence" and "family clustering", so it is urgent to strengthen the prevention and treatment of pneumoconiosis of migrant workers.
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Objective To evaluate the etiology, pathogenesis, clinical manifestation, imaging features, treatments and factors related to prognosis of acute spinal spontaneous hematoma.Methods The clinical data of 38 patients with acute spinal hematoma treated in our hospital from 2011 till now were analyzed retrospectively.Duration of follow-up was 6 months.The factors influencing the prognosis were analyzed.Results Acute epidural hematomas (n=29) were much more common than subdural (n=5), subarachnoid (n=1) and intramedullary (n=3).Most hematomas were located in the cervical and thoracic vertebra regions.The etiology of acute spinal spontaneous hematoma was unknown in most patients.Twenty-nine patients were dealt with surgical intervention and 9 patients were treated conservatively.After 6-month follow up, recovery rate measured by JOA score in patients of spinal injury ASIA level A and B was (51.26 ±38.97), and level C, D and E was (80.33 ±25.83), P<0.05.Recovery rate in patients with hematoma discovered in less then 24 hours treated with surgical decompression was (64.79 ±36.10), and that in those with hematoma present over 24 hours was (34.54 ±30.17), P<0.05.Conclusions Acute spinal hematoma always caused by unknown etiology, and usually manifests itself in a sudden onset of pain and neurological deficits.The early diagnosis mainly depends on MRI.Patients presenting with severe neurologic dysfunction or showing signs of progressive deficit should have immediate surgical intervention. The status of neurological deficits before surgery and the length of interval between onset and surgical intervention are associated with recovery.
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[Objective]To investigate the inhibitory effect of zoledronic acid(ZA) on osteolysis induced by human periprosthetic tissue in a novel animal model.[Method]Human periprosthetic tissue that was harvested from a patient receiving total hip revision was grafted on the calvaria bone of SCID beige mice. ZA was injected directly beneath the scalp of mice once,2 days post surgery. The mice were sacrificed 2 or 4 weeks after transplantation and the calvaria with grafted human tissue was collected for further detection.[Result]The grafted tissues were found survive for at least 4 weeks in the animals. Bone collagen collapse of the calvaria caused by periprosthetic tissue was demonstrated by HE staining. Significantly higher level of TNF-?,IL-6,RANKL and CPK both in gene expression and protein release were detected in PT grafted group,as compared with the control. Once administration of ZA remarkably reduced the expression of RANKL and CPK in both gene and protein level without affecting TNF-? and IL-6.[Conclusion]Once and local injection of ZA effectively inhibits the osteolysis induced by human periprosthetic tissue with a long lasting effect. The novel animal model could serve for evaluating the pharmaceutical effect on periprosthetic osteolysis.
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Joint prosthesis is one of the most successful procedures in orthopaedic surgery and has considerably improved the quality of life for patients affected by terminal joint disease. However,a number of joint prosthesis ultimately failed because of aseptic loosening. There have been major advances in the understanding of aseptic loosening. The RANKL-RANK-OPG-NF-?B system has been shown to play a fundamental role in aseptic loosening. We review how the RANKL-RANK-OPG-NF-?B system regulates aseptic loosening and aseptic loosening drug intervention.