BACKGROUND: Authors' previous studies showed that U-shaped plate could give continuously pressure to broken ends of fractured bone and make the fractured region in an optimal environment and promote union of fracture.OBJECTIVE: To discuss the loading ability of modified U-shaped plate.DESIGN, TIME AND SETTING: The single sample experiment was performed at the Laboratory of Materials Mechanics, Central South University from December 1990 to April 2001.MATERIALS: Plain bone plate is provided by Jiangsu Jinlu, China. AO plate and dynamic compression plate are purchased from MATHYS, Switzerland. U-shaped plate is a modified plate with a U-shaped arm in the middle of a common plate (Patent number 012497304).METHODS: We measured the mechanics of experimental mode to understand the compressing and distorting ability, m test theoretic calculation and to compare with common plate, AO plate and dynamic compression plate.MAIN OUTCOME MEASURES: Bending ability and distorting ability.RESULTS: Compared with the same usage of AO-Plate and dynamic compression plate at sagittal face, the bending ability of U-shaped plate could increase respectively by 107.5% and 21.5%, and the distorting ability increase respectively by 406% and 58%. Distorting ability increased by 31.9%, compared with limited contact dynamic compress plate (LC-DCP).CONCLUSION: Modified U-shaped plate is an eligible plate of enough strength and rigidity, compared with common AO plate and compress plate.

Objective To analyze the constituent of the 32 kD protein band and its expression in schizophrenia se?rum. Methods Sixty schizophrenia patients and 58 health controls were recruited. The serum samples were collected and precipitated with 7%PEG. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) was used to ob?tain the abnormal 32 kD proteins band in patients. This protein band was cut and then analyzed using mass spectrometric technique. Results The 32 kD protein band was present in 38 schizophrenia patients but not in control and positive rate was 63.33%. The mass spectrometric analysis showed that 32 kD protein band contained 14 proteins ranging from 30 kD to 35 kD, including 6 high-frequency proteins (cDNA coded protein 1 and 2, Apolin protein A-1, Isoform 2 of ficolin-2, Complement factor H and clusterin) and 8 low-frequency proteins (IgG H chain, zinc-alphg-2-glycoprotein, fermitin,family apolin protein L-1, isoform 10 of collectin-1, purine nucleoside, anne xin and cDNA coded protein 3). Three cD?NA coded unknown proteins were highly similar to complement C4-B, β2-glycoprotein and erythrocyte band 7 integral membrane protein. Conclusion There is a unknown specific 32 kD protein that is consisted mainly of fourteen proteins in serum of schizophrenia.

Objective To observe in vitro the effect of mechanical stress at different intensities on the pro-liferation, apoptosis and extracellular matrix of degenerative human nucleus pulposus cells. Methods The cells were isolated and cultured in vitro, and divided into a control group, a low-intensity group, a medium-intensity group and a high-intensity group. The low-, medium- and high-intensity groups were stretched mechanically by 1000 μ, 2000μor 4000μrespectively for 6 hours using a four-point bending system, while the control group was not stressed. Flow cytometry was used to explore any changes in the cell cycle and the proliferation index ( PI) . The expression of proliferating cell nuclear antigen ( PCNA) , B-cell lymphoma-2 ( BCL-2)/Bax, collagen II and aggrecan were meas-ured using real-time quantitative polymerase chain reactions. Results The mechanical stretching significantly influ-enced proliferation, apoptosis and the extracellular matrices compared with the control group. The PI and PCNA ex-pression increased at first and then decreased gradually with the exercise intensity. Compared with the control group, the mRNA expression level of Bcl-2/Bax increased significantly to 1.53 times that of the control group after 1000 μstretching, but to only 0.71 times that of the control group at 2000μand 0.43 times at 4000μ. The gene expression of collagen II increased significantly by 1. 1 times and that of aggrecan by 1. 3 times after 1000 μ stress stimulation compared with the control group ( P≤0.05) . However, the expression of collagen II and aggrecan was inhibited sig-nificantly at 2000 and 4000 μ , with the lowest levels at 4000 μ (P≤0.05). Conclusion Stretching at different intensities has different effects on the proliferation, apoptosis and extracellular matrix of human pulposus cells with degenerate nuclei.