Background The prevalence of low back pain among workers using vibrating tools in the automobile manufacturing industry is high; however, research on associated risk factors remains limited. Objective To investigate the association between use of vibrating tools and low back pain among automobile manufacturing workers, and to estimate related population attributable risk percentage (PAR%). Methods A cross-sectional survey was conducted using the Chinese Musculoskeletal Disorders Questionnaire among workers with over one year of service in an automobile manufacturing enterprise. Workers were categorized into an exposed group (vibrating tool users) and a control group (non-users) based on their use of vibrating tools during work. The variables showing statistically significant differences between the two groups were selected as covariates for matching by 1∶2 nearest-neighbor propensity score. Chi-square test was used to compare the prevalence of low back pain between the matched exposed and control groups. Log-binomial regression model was employed to calculate the prevalence ratio (PR), and the PAR% of low back pain attributable to vibrating tool use was subsequently determined. Results A total of 6973 valid questionnaires were collected, comprising 5676 males and 1297 females, with an overall low back pain prevalence of 40.3% (2809/6973). The exposed group included 1255 workers (1134 males, 121 females), with a mean age of (44.2 ± 8.7) years and a mean tenure in the current position of (23.5 ± 9.9) years; the matching control group consisted of 2510 workers (2279 males, 231 females), with a mean age of (44.7 ± 8.6) years and a mean tenure in the current position of (24.0 ± 10.0) years. The prevalence of low back pain was 76.7% (963/1255) in the exposed group, significantly higher than the 29.9% (750/2510) in the control group (P<0.001). The log-binomial regression analysis showed a PR of 2.57 (95%CI: 2.28, 2.90) for the exposed group, with a PAR% of 22.03%. Conclusion The use of vibrating tools among automobile manufacturing workers is positively associated with reporting low back pain. Implementing effective measures to mitigate vibration hazards is crucial for reducing the burden of low back pain in this population.

ObjectiveTo investigate the effects of Linggui Zhugantang on mitochondrial fission and fusion and silencing information regulator 3（Sirt3）/adenosine monophosphate dependent protein kinase （AMPK） signaling pathway in chronic heart failure （CHF） rats after myocardial infarction （MI）. MethodSD rats randomly divide into sham operation group （normal saline ，thread only without ligature）， model group （normal saline， ligation of the left anterior descending coronary artery proximal to the heart）， Linggui Zhugantang group （4.8 g·kg^-1） and Captopril group （0.002 57 g·kg^-1）， with 10 rats in each group. Administere drug continuously for 28 days. Echocardiography detected cardiac function parameters. Hematoxylin eosin （HE） staining observed the pathological changes of the heart. Immunofluorescence detected the levels of reactive oxygen species （ROS）. JC-1 detect mitochondrial membrane potential. Colorimetry measure adenosine triphosphate （ATP）， superoxide dismutase （SOD）， malondialdehyde （MDA）， mitochondrial respiratory chain complex activity （Ⅰ-Ⅳ）. TdT-mediated dUTP nick end labeling （TUNEL） staining detected the apoptosis rate of myocardial tissue. Western blot detected protein expression levels of Sirt3， phosphorylated AMPK （p-AMPK）， phosphorylated dynamic-related protein 1（p-Drp1）， mitochondrial fission protein 1（Fis1）， mitochondrial fission factor （MFF）， optic atrophy protein 1（OPA1）. ResultCompared to the sham group， the left ventricular end diastolic diameter （LVIDd） and left ventricular end systolic diameter （LVIDs） were significantly increased in model group （P<0.01）， while the left ventricular short axis shortening rate （LVFS） and left ventricular ejection fraction （LVEF） were significantly decreased （P<0.01）. There were inflammatory cell infiltration and obvious pathological injury in myocardial tissue. ROS， MDA levels and myocardial cell apoptosis rate were significantly increased （P<0.01）， SOD level， ATP content， and membrane potential were significantly decreased （P<0.01）. The activity of mitochondrial respiratory chain complexes （Ⅰ-Ⅳ） was significantly decreased （P<0.01）. Levels of p-Drp1， Fis1， MFF proteins were significantly up-regulated （P<0.01）， while Sirt3， p-AMPK， OPA1 proteins level were significantly down-regulated （P<0.01）. Compared with model group， LVIDd and LVIDs were significantly decreased （P<0.01）， LVEF and LVFS were significantly increased （P<0.01）. Inflammatory cell infiltration and pathological damage of myocardial tissue were significantly relieved. ROS， MDA levels and myocardial cell apoptosis rate were significantly decreased in Linggui Zhugantang group and Captopril group （P<0.01）， SOD level， ATP content， and membrane potential significantly increased （P<0.01）. The activity of mitochondrial respiratory chain complexes （Ⅰ-Ⅳ） increased significantly （P<0.01），and p-Drp1， Fis1， MFF protein levels were significantly down-regulated （P<0.01）， Sirt3， p-AMPK， OPA1 protein were significantly up-regulated （P<0.01）. ConclusionLinggui Zhugantang can alleviate oxidative stress and apoptosis damage of myocardial cells， maintain mitochondrial function stability， and its effect may be related to mitochondrial mitosis fusion and Sirt3/AMPK signaling pathway.

ObjectiveTo explore the impact of overtime work on work-related musculoskeletal disorders in male employees in the automobile manufacturing industry. Methods A total of 1 731 male employees with more than one year of working experience from an automobile manufacturing industry were selected as the research subjects using judgment sampling method. The Musculoskeletal Disorder Questionnaire was used to investigate the prevalence of musculoskeletal disorder. Employees were divided into control group and overtime group, and a 1∶1 matching was performed using propensity score matching method, and 573 pairs were successfully matched. The prevalence of WMSDs in various body parts was compared between the two groups. Results The overtime working rate of the research subjects was 34.2%, and the prevalence of WMSDs was 57.1%. Overtime work increased the risk of WMSDs in the neck, shoulders, upper back, lower back, ankle/feet, and overall body of the workers (all P<0.05), with the odd ratio and 95% confidence interval of 1.43 (1.10-1.85), 1.38 (1.06-1.80), 1.42 (1.07-1.89), 1.28 (1.01-1.62), 1.37 (1.01-1.87), and 1.49 (1.17-1.89), respectively. However, there was no association between overtime work and the risk of WMSDs in the elbows, hands/wrists, hips, and knees of the subjects (all P>0.05). Conclusion Overtime work increases the risk of WMSDs in the neck, shoulders, upper back, lower back, ankles/feet, and overall body of male employees in the automobile manufacturing industry. Enterprises should improve labor organization, reduce overtime work, and protect the health of workers.

Background China's automobile manufacture is a labor-intensive industry, and most of the welding tasks are manual operations. It is often necessary to observe the solder joints during operation, and there are many adverse health outcome-related factors involved in the work process. However, the research on the prevalence and risk factors of work-related musculoskeletal disorders (WMSDs) in the upper back of welders is still insufficient. Objective To explore the prevalence and risk factors of WMSDs in the upper back of welders from an automobile factory. Methods This was a cross-sectional study. A cluster random sampling method was used to select 972 electric welders from an automobile factory as the study subjects. The Musculoskeletal Disorders Questionnaire was used to estimate the prevalence of WMSDs in the upper back in the past year. Results The prevalence rate of WMSDs in the upper back in the welders was 42.2% (410/972). The positive rates of studied occupational risk factors were 72.5% (705/972) for maintaining same posture for a long time, 71.8% (698/972) for bending and twisting for a long time, and 64.7% (629/972) for repetitive trunk movements. The univariate analysis showed that the prevalence rates of WMSDs were significantly different among workers categorized by gender, working age, twisting and/or bending for a long time, working in the same position for a long time, lifting heavy objects in an uncomfortable position, repetitive trunk movements, being unable to exert energy due to discomfort, work involving cold or temperature changes, personnel shortage, no rest between work, working hours per week, and working in an uncomfortable position (P<0.05). The results of multiple logistic regression indicated that female, working in the same position for a long time, working in an uncomfortable position (frequently), lifting heavy objects in an uncomfortable position, and being unable to exert energy due to discomfort were associated with higher risks of reporting WMSDs in the upper back (OR=2.37, 1.46, 1.76, 1.44, and 1.50, respectively, P<0.05); the risk of reporting WMSDs in the upper back increased by 95%, 157%, and 196% for every 10 h increase in weekly working hours (41-50 h, 51-60 h, ≥61 h vs ≤40 h); adequate rest time was associated with a lower risk for WMSDs in the upper back (OR=0.70, 95%CI: 0.49-0.98). Conclusion The prevalence rate of WMSDs in the upper back of welders in the automobile factory is high, and many occupational risk factors are involved. Measures should be taken for intervention and prevention.

【Objective】 To study the blood group serology and molecular biology of patients with RhD--, so as to guide clinical blood use. 【Methods】 The EDTA-K2 anticoagulant blood of the patient was detected for Rh antigens and antibodies. Meanwhile, DNA was extracted, and the 1-10 exon of RHCE and RHAG gene was sequenced by Sanger sequencing. 【Results】 The serological test showed O type RhD--, and all spectral cells were positive. RHCE gene sequencing showed RHCE^*02/RHCE^*02, RHAG gene sequencing showed mutations at site 808 G > A and site 861 G > A of exon 6. 【Conclusion】 When patients were with RhD--, and related immune conditions such as pregnancy and/or transfusion history were present, autologous blood transfusion or plasma exchange could be an option for emergency blood use.

Objective: To explore the prevalence and risk factors of neck musculoskeletal diseases (MSDs) of welders among an automobile factory. Methods: In June 2019, a cluster random sampling method was used to select 677 electric welders from an automobile manufacturing plant in Shiyan City as the survey objects, and a questionnaire survey was conducted using the "Musculoskeletal Disorders Questionnaire" to analyze the prevalence and influencing factors of neck MSDs, and used logistic regression to analyze the relationship between the influencing factors and the prevalence of cervical MSDs. Results: The prevalence rate of MSDs in neck of welders was 54.8% (371/677) . The exposure rate of occupational factors, from high to low, were neckin a bent formord porsure was 71.6% (486/677) , repetitive head movements was 55.1% (373/677) , working in uncomfortable postures was 48.7% (330/677) and neck twisted was 46.8% (317/677) respectively. Sex, age, educational level, length of service, smoking, neck tilt, neck twist, working in uncomfortable posture and head repetitive movements were the risk factors of neck MSDs (P<0.05) . Multiple logistic regression analysis showed that, the main influencing factors of neck MSDs were sex, education level, age, length of service, smoking, neck tilt, working in uncomfortable posture (OR = 2.11, 2.03, 1.83, 1.21, 1.78, 1.90, 1.58, 95%CI: 1.28~3.48、1.47~2.81、1.33~2.52、1.03~1.41、1.22~2.60、1.28~2.83、1.11~2.27, P<0.05) , rest had protective effect on neck MSDs (OR= 0.38, 95%CI: 0.17~0.88, P<0.05) . Conclusion: Welders in automobile factory was highly exposed to occupational risk factors for neck MSDs. Occupational risk factors such as neck in a bent forward posture, working in an uncomfortable posture, prolonged siting, repetitive head movement should be the focus of intervention.
Automobiles ; Cross-Sectional Studies ; Humans ; Metal Workers ; Musculoskeletal Diseases/epidemiology* ; Occupational Diseases/epidemiology* ; Prevalence ; Risk Factors ; Surveys and Questionnaires

ObjectiveTo investigate the protective effect of Linggui Zhugantang （LGZGT）-medicated serum against H₂O₂-induced injury in H9c2 cells and its relationship with the phosphatidylinositol 3- kinase/protein kinase B （PI3K/Akt） signaling pathway. MethodThe LGZGT-medicated serum and blank serum were prepared based on serum pharmacology. H9c2 cells were cultured in vitro and divided into a normal group， an H₂O₂ group， a 20% blank serum group， and a 20% LGZGT-medicated serum group. The cells were treated with corresponding drugs for 12 h and cultured with 100 μmol·L^-1 H₂O₂ for another 6 h. The effect of 20% LGZGT-medicated serum on the proliferation activity of H9c2 cells induced by H₂O₂ was detected by cell counting kit-8 （CCK-8） assay. Mitochondrial reactive oxygen species （ROS） level was detected by the fluorescence probe. The levels of malondialdehyde （MDA）， lactate dehydrogenase （LDH）， catalase （CAT）， and glutathione peroxidase （GSH-Px） were detected by colorimetry. Western blot was used to detect the protein expression levels of phosphoinositide 3-kinase （PI3K）， phosphorylated-PI3K （p-PI3K）， protein kinase B （Akt）， and phosphorylated-Akt （p-Akt）. Real-time fluorescence-based quantitative polymerase chain reaction （Real-time PCR） was used to detect mRNA expression of PI3K and Akt. Flow cytometry was used to detect the apoptosis rate. After the addition of PI3K inhibitor LY294002， the levels of mitochondrial ROS， LDH， and GSH-Px， protein expression of PI3K， p-PI3K， Akt， and p-Akt， and cell apoptosis rate were detected. ResultCompared with the normal group， the H₂O₂ group showed blunted cell viability （P<0.01）， increased levels of mitochondrial ROS， MDA， and LDH （P<0.01）， decreased levels of CAT and GSH-Px （P<0.01）， reduced phosphorylation and mRNA expression of PI3K and Akt （P<0.05， P<0.01）， and increased apoptosis rate （P<0.01）. Compared with the H₂O₂ group， the 20% LGZGT-medicated serum group showed potentiated cell viability， reduced levels of mitochondrial ROS， MDA， and LDH （P<0.01）， increased levels of CAT and GSH-Px （P<0.01）， up-regulated phosphorylation and mRNA expression of PI3K and Akt （P<0.05， P<0.01）， and decreased apoptosis rate （P<0.01）. The combined use of LGZGT-medicated serum and inhibitor LY294002 reversed the above-mentioned effects of LGZGT-medicated serum on H9c2 cells （P<0.05， P<0.01）. ConclusionThe protective effect of LGZGT-medicated serum on H₂O₂-induced H9c2 cell injury may be related to the regulation of the PI3K/Akt signaling pathway to reduce oxidative stress and apoptosis.

Thoracolumbar osteoporotic vertebral compression fracture（OVCF）is more common in patients with osteoporosis，which seriously affects the life quality of the elderly. Percutaneous vertebroplasty（PVP）and percutaneous kyphoplasty（PKP）are the conventionally effective strategies for treatment of OVCF，whereas quite a lot OVCF patients still sufferred from residual back pain，affecting postoperative recovery. Bone density，postoperative infection，cement leakage induced nerve injury，fascia injury and facet joint violation may be the potential factors for residual back pain. In this study，the authors review advances in the definition of residual back pain in OVCF after surgery and related risk factors including injured vertebrae，bone density，fascia injury，intravertebral vacuum cleft，cement volume and distribution，surgical related factors including facet joint violation，hoping to provide a reference for clinical treatment.

Objective: To investigate the effect of thoracic paravertebral nerve block combined with general anesthesia in the perioperative period of elderly patients with non-small cell lung cancer (NSCLC). Methods: 50 elderly patients with NSCLC in our hospital from June 2015 to June 2018 were randomly divided into control group (n=25) and observation group (n=25). The control group was given general anesthesia, while the observation group was given thoracic paravertebral nerve block combined with general anesthesia. Postoperative recovery (recovery time, extubation time, ambulation time, feeding time) and hospitalization time, visual analogue scale (VAS) score at 2, 12, 24 and 48 hours after operation, serum tumor markers [cyfra21-1], carbohydrate antigen 125 (CA125), CA199, carcinoembryonic antigen (CEA) were counted and compared. The heart rate (HR), mean arterial pressure (MAP) [preoperative (T₁), 15 minutes (T₂), 5 minutes (T₃) after anesthesia], and the incidence of adverse reactions were recorded. Results: ⑴ Postoperative recovery and hospitalization time: hospitalization time, recovery room stay time, extubation time, out-of-bed activity time and eating time of the observation group were shorter than those of the control group (P<0.05); ⑵ Pain degree: VAS score of the observation group was lower than that of the control group at 2, 12 and 24 hours after operation (P<0.05), and 48 hours after operation VAS score of the observation group was lower than that of the control group (P<0.05). There was no significant difference between the two groups (P>0.05); ⑶ Serum tumor markers: there was no significant difference in serum cyfra21-1, CA125, CA199 and CEA levels between the two groups before operation (P>0.05). After operation, serum cyfra21-1, CA125, CA199 and CEA levels of the two groups were decreased, and the indexes in observation group were lower than that of the control group (P<0.05); ⑷ Hemodynamics: there was no significant difference in HR and MAP between the two groups at T₁ (P>0.05). HR and MAP in the two groups at T₂ were lower than those at T₁, but the levels of each index in the observation group were higher than those in the control group (P<0.05). HR and MAP in the observation group at T₃ stage returned to the level at T₁, and there was significant difference between the two groups (P<0.05); ⑸ Adverse reactions: the incidence of adverse reactions in the observation group (8.0%) was lower than that in the control group (32.0%, P<0.05). Conclusions The application of thoracic paravertebral nerve block combined with general anesthesia in total thoracoscopic lobectomy is safe and can inhibit the large fluctuation of hemodynamics in elderly patients with non-small cell lung cancer, shorten hospitalization time and post-operative rehabilitation time, alleviate post-operative pain, reduce the content of serum tumor markers, and reduce the risk of adverse reactions.

Objective To analyze the rate and distribution of positive provocative tests in patients with inducible urticaria,and to investigate the role of provocative tests in the etiological diagnosis of chronic urticaria.Methods Among patients who visited the special clinic for urticaria in the Department of Dermatology of the Third Affiliated Hospital,Sun Yat-sen University from January 2016 to December 2017,127 patients with suspected inducible urticaria were selected,and underwent 6 provocative tests for inducible urticaria,including delayed pressure urticaria provocative test (DPUPT),symptomatic dermographism provocative test (SDPT),vibratory angioedema provocative test (VAEPT),cold urticaria provocative test (CUPT),heat urticaria provocative test (HUPT),and aquagenic urticaria provocative test (AUPT).Statistical analysis was carried out by chi-square test for comparison of positive rates between male and female patients.Results Among the 127 patients with suspected inducible urticaria,106(83.46％) showed one or more positive provocative tests.The positive rate of SDPT was the highest (79.53％,101/127),followed by HUPT (22.05％,28/127) and CUPT (9.45％,12/127).The positive rate of HUPT was significantly higher in female patients (30.14％,22/73) than in male patients (11.11％,6/54;X2 =4.301,P ＜ 0.05).The patients with positive DPUPT,VAEPT and AUPT all showed positive SDPT responses.Among the 12 patients with positive CUPT reactions,11 showed positive SDPT responses.Among the 28 patients with positive HUPT reactions,26 showed positive SDPT responses.Of the 48 patients with one or more positive non-SDPT provocative tests,the patients with 2 positive non-SDPT provocative tests accounted for 18.75％ (9/48).Conclusion Provocation tests for inducible urticaria are of great clinical significance for the etiological diagnosis of chronic urticaria.