Objective To commission a Mobetron intra-operative mobile accelerator and analyze the characteristics of its electron beams. Methods The dosimetrie characteristics of the electron beams genera-ted by Mobetron accelerator were measured and compared with those generated by conventional accelerator (Primus, Siemens). M oberton accelerator can generate electron beams of nominal energies of 4,6,9 and 12 MeV. The measurement items were as followings : percentage depth dose perpendicular to water phantom sur-face and beam profiles parallel to water phantom surface, output factors, applicator leakage, electron beam at-tenuation made by lead blocks,and machine output calibration. The measurement devices included a three-dimensional ( 3 D) water scanning phantom, an electrometer, a 0.6 cm3 Farmer ionization chamber, a parallel-plate ionization chamber and solid water slabs. During measurement, all applicators of different tilt angles and diameters were attached to the machine head,and their ends were adjusted to be tangent to the phantom surface. Results Except for the 12 MeV,skin dose for all energies was no more than 90%. The skin dose was higher for Mobetron accelerator electron beams than for regular electron beams. The Dmax depth in water for a 10 cm flat applicator were 0.7,1.3,2.0 and 2.2 cm for the 4 energies,respectively. The depths of 90% dose were 1.0,1.8,2.7 and 3.6 cm, respectively. The selected flat applicator was just 1 cm larger than the tumor bed. But for the beveled applicators,the field flatness and symmetry became worse,and con-sequently,the applicator size had to be selected based on the isodose distribution. The leakage dose at 1 cm outside the applicator was 1.2% ,5.1%, 10.0% and 9.1%, respectively. The lead thickness for full block was 1.5,3.0,4.5 and 6.0 mm,respectively. Conclusions Through the commissioning of Mobetron accel-erator, the machine characteristics are understood, and the data for clinical implementation and routine quality assurance are acquired.

Objective: To investigate the curative effects of apoptin on the multidrug-resistant model, of human osteosarcoma cell line (R-OS-732). Methods: 363 bpVP 3 gene was cloned into the vector pIRES1 and the recombinant eukaryon expression vector pIRVP3 was transfected into R-OS-732 cells with liposome. The expression of apoptin gene at transcription level was proved by RT-PCR. The pathological changes of the cells was observed by light microscope and electronmicroscope. The transfected R-OS-732 cells were collected after 48 hours. The genomic DNA extracted from the cells was observed by agarose gel electrophoresis. The apoptosis rate of the cells was analysed by flow cytometry. Results: The expression of apoptin gene at transcription level had been proved by RT-PCR. The construction changes of the two groups were obviously different under light microscope: most of R-OS-732 cells in the transfected group existed in form of being away from the bottom of the culture dish after 24 hours, in form of apoptosis after 48 hours and in form of necrosis after 72 hours; but those cells in the controlled group grow luxuriantly. And under electronmicroscope there was much change of cell nucleus between the two groups. DNA ladder of the transfected cells was observed through agarose gel electrophoresis only one band was observed in the controlled group; but bands of fragmented DNA observed in ositive control group. Flow cytometry analysis showed that the apoptosis rate of the cells in the transfected group was relatively higher than that of the controlls( P

Objective To investigate the expressions of Transforming Growth Factorβ2 (TGF-β2) and Smad3 in human gliomas associated with pathologic grading. Methods The expressions of TGFβ2 and Smad3 protein were detected with SP immunhistochemistry in 80 human glioma specimens. The Kapan-Meier survival curves of progression-free survival time and overall survival time in different expression levels was compared with log-rank. Results The expression of TGFβ2 and Smad3 correlated with the pathological grading (r=0.545, r=0.570, P<0.01). Both progression-free survival time and overall survival time were significantly different between low expression group and high expression group (P<0.05). Conclusion Both TGF-β2 and Smad3 correlate well with the occurrence and differentiation of human gliomas,which help for the diagnosis, treatment and prognosis judgment．

Objective To investigate the expression level of fatty acid synthase (FASN) in different grades ofgliomas and its relationship with glioma malignancy.Methods Glioma U87 and U373 cell lines were routinely cultured in vitro;immunofluorescence assay was performed to detect the cellular localization of FASN in glioma U87 and U373 cell lines.Sixty-seven human glioma samples,collected in our hospital from March 2012 to March 2013,were used in our study;grade Ⅰ was noted in three samples by WHO grading,grade Ⅱ in 29,graded Ⅲ in 22,and grade Ⅳ in 13;immunohistochemistry was performed to detect the expression levels of FASN,CD34 and Ki-67 and microvascular density (MVD) in these human glioma samples.Spearman's correlation was used to analyze the relationship between FASN expression and both Ki-67 expression and MVD in human gliomas.Results (1) FASN could express in the cytoplasm of glioma U87 and U373 cell lines.(2) immumohistochemical staining indicated that FASN mainly located in the cytoplasm,Ki-67 in the cell nucleus,and CD34 in the cytomembrane.FASN expression in samples of grade Ⅰ (3.3683±0.6549) was significantly lower than that in samples of grade Ⅱ (4.0512±0.4859,P＜0.05),and FASN expression in samples of grade Ⅲ (4.1881±0.5755) was significantly lower than that in samples of grade Ⅳ (4.6996±0.5164,P＜0.05);MVD in samples of grade Ⅱ was significantly smaller than that in samples of grade Ⅲ(P＜0.05),and MVD in samples of grade Ⅲ was significantly lower than that in samples of grade Ⅳ(P＜0.05);Ki-67 expression in samples of grade Ⅱ was significantly lower than that in samples of grade Ⅲ (P＜0.05).(3) There was a positive and significant correlation between FASN expression and MVD (r=0.606,P=0.030);a positive and significant correlation between FASN expression and Ki-67 was also noted (r=0.636,P=0.014).Conclusion High expression level of FASN indicates high proliferation capability and high blood supply in haman gliomas.