The correlation between occupational burnout and sleep quality among steelworkers / 中国职业医学

{L-End}Objective To analyze the correlation between occupational burnout and sleep quality among steelworkers. {L-End}Methods A total of 11 491 steelworkers from a large steel enterprise in Gansu Province were selected as the research subjects using convenient sampling method. The Burnout Questionnaire and the Pittsburgh Sleep Quality Index Scale were used to investigate their occupational burnout and sleep quality. Hierarchical regression analysis was used to analyze the effects of occupational burnout on the sleep quality. {L-End}Results The detection rate of occupational burnout and sleep disorder were 50.4% and 39.0%, respectively. There was a positive correlation between the level of occupational burnout and the total score of sleep quality (Spearman correlation coefficient=0.454, P<0.05). The results of hierarchical regression analysis, adjusting for confounding factors such as gender, age, marital status, education level, alcohol consumption, exercise, weekly working hours, seniority, work shift, noise exposure, dust exposure, and high-temperature work, showed that the score of occupational burnout was positively related to the score of sleep quality(P<0.01), explaining 16.0% of the variance in the score of sleep quality among these steelworkers. {L-End}Conclusion The detection rate of occupational burnout and sleep disorders are relatively high among the steelworkers in this enterprise. Higher levels of occupational burnout are associated with poorer sleep quality. Alleviating occupational burnout among steelworkers may contribute to improving their sleep quality.

Influences of Site-directed Mutagenesis of a Recombinant Didintegrin from Gloydius blomhoffi brevicaudus on Its Biological Activities / 中国生物化学与分子生物学报

Arg-Gly-Asp (RGD) is a unique minimal integrin-binding sequence found within several glycoprotein ligands and also in snake-venom disintegrins. Adinbitor, a protein with 73 amino acid residues including 12 cysteins and an RGD motif, was cloned from Gloydius blomhoffi brevicaudus in my laboratory. As a new member of disintegrin family, adinbitor can inhibit both human platelet aggregation induced by ADP and angiogenensis in vivo and in vitro, the typical characters of disintegrin family. To separate the effect of inhibiting platelet aggregation from that of inhibiting angiogenensis, the motif KGD was introduced into adinbitor cDNA to replace RGD by site-directed and PCR-based mutagenesis. The recombinant protein (recombinant adinbitor (KGD)) was expressed in E. coli BL21 and purified through the His· Bind affinity chromatography. Recombinant adinbitor (KGD) could inhibit ADP-induced platelet aggregation with IC50 value of 85 nmol/L. Considerably, it was a more effective inhibitor on platelet aggregation than recombinant adinbitor (RGD), which has an IC50 of 150 nmol/L. Interestingly, recombinant adinbitor (KGD) has no potency in inhibiting angiogenesis in vivo compared with recombinant adinbitor (RGD). These findings showed that KGD containing adinbitor was more suitable for inhibiting ADP-induced human platelet aggregation as a potential and specific inhibitor of human platelet aggregation, which might have promising therapeutic potential as an antithrombotic agent.

Inhibitory effects and mechanism of arsenic trioxide on the growth of melanoma B16 cells / 中国药理学通报

Aim The present study was designed to investigate the growth inhibition and anti-angiogenesis of arsenic trioxide (As 2O 3) on B16 cells xenografts in C57BL/6J mice and observe the effects of As 2O 3 on cell proliferation, cell morphology, cell cycle and apoptosis in vitro. Methods Mice melanoma cell line B16 was transplanted into C57BL/6J mice. The weight of tumor and percent of tumor development were examined after As 2O 3 intraperitoneal administration. HE staining and immunohistochemistry for Ⅷ-R Ag were performed to detect the microvessel density in tumor tissues. CellTiter 96 Aqueous One was used to determine the cell proliferation. Giemsa and Feulgen staining were used to observe the morphological changes of the cells. Cell cycle and apoptosis were analyzed by flow cytometry (FCM). Results As 2O 3 significantly inhibited the tumor growth in vivo, with an inhibitory rate of 81.61%. The microvessel density in tumor tissues was obviously reduced after treated with As 2O 3. There was obviously a concentration-dependent relationship between As 2O 3 and the inhibition of B16 cells proliferation (P

THE EFFECTS OF ?-ELEMENE ON DNA-BINDING SPECIFICITY AND RNA POLYMERASE INHIBITORY ACTIVITY / 中国药理学通报

?-elemene that is an element of the Essential oil of the Cuicu-ma Wenyujin showed appreciable anticancer ability. The experimental results showed that the RNA polymerase activity was inhibited by ?-elemene at concentrations of 0.0074 mol/L~0.0172 mol/L. The study of thermal denaturation indicated that the Tm of DNA was decreased after adding ?-elemene. The fluorescent analysis of ?-elemene bound to DNA showed that the intensity of fluorescence was increased. The peak of absorption of DNA was shifted from 260 nm to 240 nm after treatment with ?-elemene.