Neck musculoskeletal disorders and their influence factors among welders in an automobile factory / 中华劳动卫生职业病杂志

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.

Septation of the Intrapericardial Arterial Trunks in the Early Human Embryonic Heart / 中华医学杂志(英文版)

<p><b>Background</b>Outflow tract (OFT) septation defects are a common cause of congenital heart disease. Numerous studies have focused on the septation mechanism of the OFT, but have reported inconsistent conclusions. This study, therefore, aimed to investigate the septation of the aortic sac and the OFT in the early embryonic human heart.</p><p><b>Methods</b>Serial sections of 27 human embryonic hearts from Carnegie stage (CS) 10 to CS19 were immunohistochemically stained with antibodies against α-smooth muscle actin (α-SMA) and myosin heavy chain.</p><p><b>Results</b>At CS10-CS11, the OFT wall was an exclusively myocardial structure that was continuous with the aortic sac at the margin of the pericardial cavity. From CS13 onward, the OFT was divided into nonmyocardial and myocardial portions. The cushion formed gradually, and its distal border with the OFT myocardium was consistently maintained. The aortic sac between the fourth and sixth aortic arch arteries was degenerated. At CS16, the α-SMA-positive aortopulmonary septum formed and fused with the two OFT cushions, thus septating the nonmyocardial portion of the OFT into two arteries. At this stage, the cushions were not fused. At CS19, the bilateral cushions were fused to septate the myocardial portion of the OFT.</p><p><b>Conclusions</b>Data suggest that the OFT cushion is formed before the aortopulmonary septum is formed. Thus, the OFT cushion is not derived from the aortopulmonary septum. In addition, the nonmyocardial part of the OFT is septated into the aorta and pulmonary trunk by the aortopulmonary septum, while the main part of the cushion fuses and septates the myocardial portion of the OFT.</p>

Blood Pressure Associated with Arsenic Methylation and Arsenic Metabolism Caused by Chronic Exposure to Arsenic in Tube Well Water / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>The effects of arsenic exposure from drinking water, arsenic metabolism, and arsenic methylation on blood pressure (BP) were observed in this study.</p><p><b>METHODS</b>The BP and arsenic species of 560 participants were determined. Logistic regression analysis was applied to estimate the odds ratios of BP associated with arsenic metabolites and arsenic methylation capability.</p><p><b>RESULTS</b>BP was positively associated with cumulative arsenic exposure (CAE). Subjects with abnormal diastolic blood pressure (DBP), systolic blood pressure (SBP), and pulse pressure (PP) usually had higher urinary iAs (inorganic arsenic), MMA (monomethylated arsenic), DMA (dimethylated arsenic), and TAs (total arsenic) than subjects with normal DBP, SBP, and PP. The iAs%, MMA%, and DMA% differed slightly between subjects with abnormal BP and those with normal BP. The PMI and SMI were slightly higher in subjects with abnormal PP than in those with normal PP.</p><p><b>CONCLUSION</b>Our findings suggest that higher CAE may elevate BP. Males may have a higher risk of abnormal DBP, whereas females have a higher risk of abnormal SBP and PP. Higher urinary iAs may increase the risk of abnormal BP. Lower PMI may elevate the BP. However, higher SMI may increase the DBP and SBP, and lower SMI may elevate the PP.</p>

Transcatheter closure of ventricular septal defect in patients with aortic valve prolapse and mild aortic regurgitation: Feasibility and preliminary outcome

Objective: To evaluate the feasibility, safety and efficacy of transcatheter closure of ventricular septal defect (VSD) in patients with aortic valve prolapse (AVP) and mild aortic regurgitation (AR). Methods: Between January 2008 and July 2014, transcatheter closure of VSD was attempted in 65 patients. Results: The total intermediate closure successful rate in all subjects was 96.9%. During the perioperative period, no death, major bleeding, pericardial tamponade, occluder dislodgement, residual shunt or hemolysis occurred. Two procedures had been forced to suspend due to significant aggregation of device related aortic regurgitation, three cases of transient complete left bundle branch block occurred but did not sustain. At 1-year follow-up, no patients had residual shunts and complications. Furthermore, grade of residual AR were relieved in 61.9% (39/63) cases and degree of AVP were ameliorated in 36.5% (23/63) patients;. Conclusions: Transcatheter closure VSD in selected patients with AVP and mild AR is technically feasible and highly effective. Long term safety and efficacy needs to be assessed.

Transcatheter closure of ventricular septal defect in patients with aortic valve prolapse and mild aortic regurgitation: feasibility and preliminary outcome

OBJECTIVE@#To evaluate the feasibility, safety and efficacy of transcatheter closure of ventricular septal defect (VSD) in patients with aortic valve prolapse (AVP) and mild aortic regurgitation (AR).@*METHODS@#Between January 2008 and July 2014, transcatheter closure of VSD was attempted in 65 patients.@*RESULTS@#The total intermediate closure successful rate in all subjects was 96.9%. During the perioperative period, no death, major bleeding, pericardial tamponade, occluder dislodgement, residual shunt or hemolysis occurred. Two procedures had been forced to suspend due to significant aggregation of device related aortic regurgitation, three cases of transient complete left bundle branch block occurred but did not sustain. At 1-year follow-up, no patients had residual shunts and complications. Furthermore, grade of residual AR were relieved in 61.9% (39/63) cases and degree of AVP were ameliorated in 36.5% (23/63) patients;@*CONCLUSIONS@#Transcatheter closure VSD in selected patients with AVP and mild AR is technically feasible and highly effective. Long term safety and efficacy needs to be assessed.

Absorption and excretion of fluoride and aluminum after drinking brick tea in healthy adults / 中国地方病学杂志

Objective To observe the absorption, excretion and retention of fluoride and aluminum after drinking brick tea in healthy adults. Methods The study was conducted in ten healthy volunteers by drinking brick tea solution in which the fluoride and aluminum concentrations were 5.97, 7.53 mg/L, respectively. The concentrations of fluoride and aluminum were determined in serum samples collected before and at 0.5,1.0,2.0,3.0,and 24.0 h, and in urine samples collected before and during the periods 1.0,2.0,4.0, ＞ 4.0 - ＜ 24.0 h and 24 h after drinking brick tea solution by ion-selective electrode, inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma atomic mess spectrometry. The total amounts of intake and excretion of fluoride and aluminum in healthy volunteers during 24.0 h were calculated from their corresponding fluoride and aluminum ingesting from brick tea and excreting from urine. Results Before and during the periods 1.0,2.0,4.0,＞ 4.0 - ＜ 24.0 h and 24.0 h after drinking brick tea solution, the urinary fluoride concentrations were (0.50 ±0.14), (2.14 ± 0.90), (1.57 ± 0.93), (2.43 ± 1.49), (1.91 ± 0.69), (0.58 ± 0.20)mg/L, respectively, and the aluminum concentrations in the urine samples were (0.35 ± 0.15), (0.65 ± 0.37), (0.50 ± 0.25), (0.52 ± 0.21 ),(0.50 ± 0.23), (0,46 ± 0.27)mg/L, respectively; the 24.0 h excreting rates of fluoride and aluminum from urine were 52.90%(4.64/8.77) and 12.38% (1.37/11.07), respectively. The fluoride concentrations in serum samples collected before and at 0.5,1.0,2.0,3.0,24.0 h after drinking brick tea solution were (0.06 ± 0.02), (0.14 ± 0.01 ), (0.21 ±0.04), (0.17 ± 0.04), (0.10 ± 0.03), (0.04 ± 0.01 )mg/L, respectively, and aluminum in those were (0.30 ± 0.05),(0.27 ± 0.01 ), (0.30 ± 0.12), (0.34 ± 0.19), (0.30 ± 0.10), (0.27 ± 0.09)mg/L, respectively. Conclusions Fluoride in brick tea is easyly to be absorbed and excreted through kidney, and the kidney excretory capacity of aluminum in brick tea is limited. Levels of fluoride and aluminum in urine could be taken as the indicators for monitoring the prevalent extent and evaluating preventive experiment's effect on the brick tea fluoride-aluminum toxicity; and fasting serum fluoride and aluminum levels could be taken as indicators for estimating the toxic condition of the brick tea fluoride-aluminum toxicity.

Septation and shortening of outflow tract in embryonic mouse heart involve changes in cardiomyocyte phenotype and alpha-SMA positive cells in the endocardium / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Studies on human, rat and chicken embryos have demonstrated that during the period of outflow tract septation, retraction of the distal myocardial margin of the outflow tract from the junction with aortic sac to the level of semilunar valves leads to the shortening of the myocardial tract. However, the mechanism is not clear. So we investigated the mechanism of outflow tract shortening and remodeling and the spatio-temporal distribution pattern of alpha-SMA positive cells in the outflow tract cushion during septation of the outflow tract in the embryonic mouse heart.</p><p><b>METHODS</b>Serial sections of mouse embryos from embryonic day 9 (ED 9) to embryonic day 16 (ED 16) were stained with monoclonal antibodies against alpha-SCA, alpha-SMA, or desmin, while apoptosis was assessed using the terminal deoxyribonucleotidy transferase-mediated dUTP-digoxigenin nick-end labeling (TUNEL) assay.</p><p><b>RESULTS</b>Between ED 11 and ED 12, the cardiomyocytes in the distal portion of the outflow tract were observed losing their myocardial phenotype without going into apoptosis, suggesting that trans-differentiation of cardiomyocytes into the cell components of the free walls of the intrapericardial ascending aorta and pulmonary trunk. The accumulation of alpha-SMA positive cells in the cardiac jelly began on ED 10 and participated in the ridge fusion and septation of the outflow tract. Fusion of the distal ridges resulted in the formation of the facing walls of the intrapericardial ascending aorta and pulmonary trunk. Fusion of the proximal ridges was accompanied by the accumulation of alpha-SMA positive cells into a characteristic central whorl, in which cell apoptosis could be observed. Subsequent myocardialization resulted in the formation of the partition between the subaortic and subpulmonary vestibules.</p><p><b>CONCLUSIONS</b>The shortening of the embryonic heart outflow tract in mice may result not from apoptosis, but from the trans-differentiation of cells with cardiomyocyte phenotype in the distal portion of the outflow tract into the cell components of the free walls of the intrapericardial ascending aorta and pulmonary trunk. The primary roles of alpha-SMA positive cells in the septation and remodeling of the outflow tract may assure proper fusion of the outflow ridges and form the facing walls of the intrapericardial ascending aorta and pulmonary trunk.</p>