The Antileukemia Activity of ZSTK474 on U937 Cells / 中国实验血液学杂志

OBJECTIVE@#To investigate the antileukemia activity of phosphatidylinositol-3 kinase (PI3K) inhibitor ZSTK474 on human leukemia cell line U937.@*METHODS@#MTT, soft agar assay, flow cytometric analysis and western blot were used to detect the effect of ZSTK474 on U937 cell proliferation, tumorigenicity, cell cycle, cell apoptosis and phosphorylation levels of the key factor of PI3K/AKT pathway. Chou-Talalay method was used to evaluate the combination of ZSTK474 with Cytarabine or Homoharringtonine.@*RESULTS@#PI3K inhibitor ZSTK474 could inhibit the proliferation and tumorigenicity of U937 cell, induce G@*CONCLUSION@#ZSTK474 can inhibit the pathway of PI3K/AKT, ZSTK474 alone or in combination with Homoharringtonine shows potential antileukemia activity on U937 cells.

Comfort analysis on ejection seat cushion based on sitting pressure / 医用生物力学

Objective To study the relationship between comfort and sitting pressure of ejection seat cushion. Methods By measuring sitting pressure distributions on seat cushions with different thickness, indices of sitting pressure such as the contact area, maximum sitting pressure and mean sitting pressure were discussed along with the subjective comfort scores to find the relationship between seat cushion comfort and indices of sitting pressure. Results The contact area, maximum sitting pressure and mean sitting pressure were significantly correlated with the subjective comfort scores. In addition, the comfort score did not increase when thickness of the seat cushion exceeded 4 cm. Conclusions The comfort of seat cushion could be well reflected and evaluated by the contact area, maximum sitting pressure and mean sitting pressure of seat cushion, and thickness of 4 cm is recommended for designing the seat cushion with material used in this paper.

Measurement and analysis on operating force from Chinese young males / 医用生物力学

Objective To establish the operating force database of Chinese young males and provide basis information for the design of operating force in working place. Methods Anthropometric parameters of 843 Chinese young males from northeast, north, northwest, southwest, southeast, central and south China were collected, including the back force, hand twisting force, arm forces in four exerting directions and with various elbow angles. The data were statistically analyzed and compared with related researches in China and abroad. ResultsFor arm forces in four exerting directions, the pushing force was greater than the pulling force, and the inward force was greater than the outward force. The pushing force was the largest and the outside outward force was the smallest. With the increase of the elbow angle, the pushing and pulling forces were increased significantly, while the inward and outward forces were decreased significantly. A significant correlation existed among the operating forces. There was significant correlation between the operating force and body weight, while weak correlation was found between the operating forces and anthropometric parameters. Operating forces of Chinese young males were relatively smaller than those of the Westerns. Conclusions By sampling on a national scale, the operating force database was established for Chinese young males. This study provides the basic data for the design of operating force in man-machine system and could be also used as reference for ergonomics researchers, occupational health workers and rehabilitation researchers.