Occupational Health Risk Assessment of Benzene, Toluene, and Xylene in Shanghai / 生物医学与环境科学（英文）

Objective@#This study was designed to conduct a retrospective and systematic occupational health risk assessment (OHRA) of enterprises that used benzene, toluene, and xylene (BTX) in Shanghai, China.@*Methods@#All data for the study were obtained from 1,705 occupational health examination and evaluation reports from 2013 to 2017, and a semiquantitative model following Chinese OHRA guidelines (GBZ/T 298-2017) was applied for the assessment.@*Results@#The selected enterprises using BTX were mainly involved in manufacturing of products. Using the exposure level method, health risk levels associated with exposure to BTX were classified as medium, negligible, or low. However, the risk levels associated with benzene and toluene were significantly different according to job types, with gluers and inkers exhibiting greater health risks. For the same job type, the health risk levels assessed using the comprehensive index method were higher than those using the exposure level method.@*Conclusion@#Our OHRA reveals that workers who are exposed to BTX still face excessive health risk. Additionally, the risk level varied depending on job categories and exposure to specific chemicals. Therefore, additional control measures recommended by OHRA guidelines are essential to reduce worker exposure levels.

In vitro and in vivo evaluation of the developed PLGA/HAp/Zein scaffolds for bone-cartilage interface regeneration / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the effect of electronspun PLGA/HAp/Zein scaffolds on the repair of cartilage defects.</p><p><b>METHODS</b>The PLGA/HAp/Zein composite scaffolds were fabricated by electrospinning method. The physiochemical properties and biocompatibility of the scaffolds were separately characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), and fourier transform infrared spectroscopy (FTIR), human umbilical cord mesenchymal stem cells (hUC-MSCs) culture and animal experiments.</p><p><b>RESULTS</b>The prepared PLGA/HAp/Zein scaffolds showed fibrous structure with homogenous distribution. hUC-MSCs could attach to and grow well on PLGA/HAp/Zein scaffolds, and there was no significant difference between cell proliferation on scaffolds and that without scaffolds (P>0.05). The PLGA/HAp/Zein scaffolds possessed excellent ability to promote in vivo cartilage formation. Moreover, there was a large amount of immature chondrocytes and matrix with cartilage lacuna on PLGA/HAp/Zein scaffolds.</p><p><b>CONCLUSION</b>The data suggest that the PLGA/HAp/Zein scaffolds possess good biocompatibility, which are anticipated to be potentially applied in cartilage tissue engineering and reconstruction.</p>

Effect of hypervolemic hemodilution on C-reactive protein level in patients receiving spinal surgery / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the changes in high-sensitivity C-reactive protein (hs-CRP) levels following acute hypervolemic hemodilution (AHH) in patients undergoing spinal surgery and assess the safety of AHH in terms of postoperative infection.</p><p><b>METHODS</b>Forty patients undergoing spinal operation were randomly assigned into observation group and control group (n=20). Each patient was infused 4 ml/kg/h lactated Ringers solution for maintenance of the total blood volume, and in the observation group, the patients received additional infusion of 4% gelofusine solution at the rate of 20 ml/kg/h 30 min before the operation. Venous blood samples were collected to monitor the hematocrit (Hct), prothrombin time (PT), activated partial thromboplastin time (APTT) and hs-CRP before anesthesia (T0), 2 h after the beginning of the operation (T1), at the end of the operation (T2), and 24 h after the operation (T3).</p><p><b>RESULTS</b>After AHH, Hct decreased significantly at T1 as compared with that at T0 (P<0.05) and that of the control group (P<0.01), but showed no significant difference between the two groups at T2. PT and APTT showed significant changes at T1 compared with T0 (P<0.05) but within the normal range, and were similar between the two groups at T3. hs-CRP increased significantly in the two groups at T3 compared with that at T0 (P<0.05), and a significant difference was noted between the two groups (P<0.01).</p><p><b>CONCLUSION</b>AHH does not affect the hemodynamics and blood coagulation of the patients undergoing spinal surgery but causes a significant elevation of hs-CRP, suggesting an increased risk of postoperative infection.</p>