Objective:The aim of this study is to explain the key role of chondrocyte ferroptosis in TMJ OA and demonstrate that abnormal occlusion stimulation is an important causative factor of ferroptosis.Methods:We observed the morphological changes of mouse condylar cartilage in unilateral anterior crossbite(UAC,an abnormal occlusion stimulation)and bilateral anterior elevation(BAE,a proliferation occlusion stimulation)mice by HE and SO staining,and analyzed the expression of intracellular GPX4 by im-munofluorescence staining,and analyzed the changes in the content of mitochondria and reactive oxygen species by JC-1 and ROS staining.Results:The UAC caused degeneration of condylar cartilage and ferroptosis of chondrocytes in mice.The accumulation of iron ions and the dysfunction of mitochondria in chondrocytes significantly upregulated.The expression of GPX4,which is a key reg-ulator in the regulation of ferroptosis was lowered in UAC mice condyle cartilage.Moreover,in BAE model the condylar cartilage hy-perplasia was observed,but not the ferroptosis of chondrocytes.Conclusion:This study revealed that the abnormal biological force caused by abnormal occlusion could induce ferroptosis of chondrocytes,and ferroptosis is one of the main factors leading to the de-generation and thinning of condylar cartilage.GPX4 could regulate the ferroptosis of chondrocytes.

Objective:To evaluate the current situation of the protective effect of hearing protection device (HPD) worn by manufacturing workers and discuss their possible influencing factors.Methods:A total of 3634 noisy workers were surveyed and tested. The study conducted surveys of workers on the use of HPD. The 3M TM E-A-R Fit TM binaural verification system was used to measure the personal attenuation device (PAR) of workers wearing HPD. Results:The M ( Q1, Q3) of baseline PAR obtained by 3634 workers was 12 (2, 19) dB. There was a statistically significant difference in baseline PAR among the three types of HPDs ( H=336.39, P<0.01) . After pairwise comparison, it was found that the baseline PAR of workers wearing foam earplugs and earmuffs was higher than that of pre-molded earplugs ( P<0.01) . There were differences in baseline PAR among workers in different industries ( Z=359.73, P<0.01) . Education level, age of using HPD, types of HPDs, noise exposure intensity, with or without knowledge of correct methods, and comfort evaluation were the main factors affecting baseline PAR ( P<0.05) . There were 1536 workers (43.4%) failed the baseline PAR test. After the intervention, the median PAR increased significantly from 1 (0, 6) dB (baseline) to 18 (14, 22) dB (after the intervention) ( P<0.01) . The follow-up test found that the follow-up PAR of 328 workers was higher than the baseline PAR of the initial test, and the follow-up PAR was higher than the post-intervention PAR of the initial test ( P<0.01) . Conclusion:Under the conditions of this study, the protective effect of HPD was affected by factors such as incorrect understanding of wearing methods, exposure to high-intensity noise, low education level, a short period of time of HPD use and low comfort of hearing protectors. The protective effect could be improved through training, optimizing the wearing of hearing protector models, and follow-up interventions. Enterprises should use suitability verification to ensure the correct selection and wearing of noisy workers.

Objective:To evaluate the current situation of the protective effect of hearing protection device (HPD) worn by manufacturing workers and discuss their possible influencing factors.Methods:A total of 3634 noisy workers were surveyed and tested. The study conducted surveys of workers on the use of HPD. The 3M TM E-A-R Fit TM binaural verification system was used to measure the personal attenuation device (PAR) of workers wearing HPD. Results:The M ( Q1, Q3) of baseline PAR obtained by 3634 workers was 12 (2, 19) dB. There was a statistically significant difference in baseline PAR among the three types of HPDs ( H=336.39, P<0.01) . After pairwise comparison, it was found that the baseline PAR of workers wearing foam earplugs and earmuffs was higher than that of pre-molded earplugs ( P<0.01) . There were differences in baseline PAR among workers in different industries ( Z=359.73, P<0.01) . Education level, age of using HPD, types of HPDs, noise exposure intensity, with or without knowledge of correct methods, and comfort evaluation were the main factors affecting baseline PAR ( P<0.05) . There were 1536 workers (43.4%) failed the baseline PAR test. After the intervention, the median PAR increased significantly from 1 (0, 6) dB (baseline) to 18 (14, 22) dB (after the intervention) ( P<0.01) . The follow-up test found that the follow-up PAR of 328 workers was higher than the baseline PAR of the initial test, and the follow-up PAR was higher than the post-intervention PAR of the initial test ( P<0.01) . Conclusion:Under the conditions of this study, the protective effect of HPD was affected by factors such as incorrect understanding of wearing methods, exposure to high-intensity noise, low education level, a short period of time of HPD use and low comfort of hearing protectors. The protective effect could be improved through training, optimizing the wearing of hearing protector models, and follow-up interventions. Enterprises should use suitability verification to ensure the correct selection and wearing of noisy workers.

Objective:The aim of this study is to explain the key role of chondrocyte ferroptosis in TMJ OA and demonstrate that abnormal occlusion stimulation is an important causative factor of ferroptosis.Methods:We observed the morphological changes of mouse condylar cartilage in unilateral anterior crossbite(UAC,an abnormal occlusion stimulation)and bilateral anterior elevation(BAE,a proliferation occlusion stimulation)mice by HE and SO staining,and analyzed the expression of intracellular GPX4 by im-munofluorescence staining,and analyzed the changes in the content of mitochondria and reactive oxygen species by JC-1 and ROS staining.Results:The UAC caused degeneration of condylar cartilage and ferroptosis of chondrocytes in mice.The accumulation of iron ions and the dysfunction of mitochondria in chondrocytes significantly upregulated.The expression of GPX4,which is a key reg-ulator in the regulation of ferroptosis was lowered in UAC mice condyle cartilage.Moreover,in BAE model the condylar cartilage hy-perplasia was observed,but not the ferroptosis of chondrocytes.Conclusion:This study revealed that the abnormal biological force caused by abnormal occlusion could induce ferroptosis of chondrocytes,and ferroptosis is one of the main factors leading to the de-generation and thinning of condylar cartilage.GPX4 could regulate the ferroptosis of chondrocytes.

Background:Fibroscan is the noninvasive method widely used to evaluate quantitatively the liver fibrosis and monitor the long-term efficacy of anti-fibrosis therapy. Aims:To study the use of Fibroscan for evaluating the efficacy of combined therapy with FuFang BieJia RuanGan tablet and antiviral drugs in patients with hepatitis B virus( HBV)-related cirrhosis. Methods:A total of 90 patients with HBV-related cirrhosis from March 2013 to September 2014 at Shanghai Ren Ji Hospital were recruited,and divided into treatment group and control group. Patients in treatment group received FuFang BieJia RuanGan tablet,and patients in control group received conventional liver-protective drugs,all the patients took nucleoside antiviral drugs at the same time. The treatment courses in both groups were 6 months. Liver stiffness measurement( LSM)was detected by Fibroscan before and after treatment. Biochemical parameters,width of portal vein and clinical symptoms were recorded. Results:After treatment,LSM was significantly decreased in both groups( P <0.05). Liver function,width of portal vein and Child-Pugh score were improved in both groups(P <0. 05),and no significant differences were found between the two groups(P>0. 05). LSM was closely associated with Child-Pugh score both before and after treatment(r=0. 484,P<0. 01;r=0. 523,P<0. 01). Patients with Child-Pugh A had lower LSM than those with Child-Pugh B or Child-Pugh C(P<0. 01). Conclusions:FuFang BieJia RuanGan tablet combined with oral antiviral drugs can remarkably improve the liver function of cirrhotic patients and prevent progression of cirrhosis. Dynamic detection of LSM can be used for monitoring drug efficacy and disease progression in patients with cirrhosis.