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Biomedical subjects

Guang-jie Chen

Publications and source records attributed to Guang-jie Chen.

7 recordsLinked to original sources
PubMed2006

[A preliminary study of beam weight optimization of intensity-modulated radiation therapy with genetic algorithm].

UNLABELLED: To study the method for dose calculation and beam weight optimization of intensity-modulated radiation therapy (IMRT). METHODS: The IMRT dose calculation model based on two-dimensional convolution was constructed, the program of dose calculation and beam weight optimization with genetic algorithm was written with Visual c#.Net, and the optimization results were analyzed. RESULTS: Genetic algorithm optimization of beam weights can produce highly conformal dose distributions within a clinically acceptable computation time. CONCLUSION: Genetic algorithm is valid and efficient in IMRT beam weight optimization, which may facilitate IMRT treatment planning.

Algorithms↗
PubMed2006

[A new mixing rigid-elastic multiresolution algorithm for medical image registration].

We present a new mixing rigid-elastic multiresolution algorithm for medical image registration from global registration to local registration in sequence. The global registration is achieved by the method of affine transformation composed of B spline, which knots are the four vertexes of the medical image. When increasing the number of the knots of the B spline along the X and Y axis, the transformation function will be more complex and "elastic", which can complete the elastic aligning for the detail of the medical image. The results of experiment demonstrated that the presented algorithm was more robust than the previous elastic algorithm of registration.

Algorithms↗
PubMed2005

[A new method for static intensity-modulated radiation therapy].

OBJECTIVE: To develop a new method for static intensity-modulated radiation therapy (IMRT) possible for implementation in smaller hospitals by incorporating accurate location equipments and treatment planning system in the available equipments for general radiotherapy. METHODS: Based on the techniques of conformal radiotherapy, a new split method for fabricating the three-dimensional physical compensator was developed to achieve IMRT. RESULTS: Experiment with the new method showed that the fabricated compensator could achieve good match between the high dosage shape in the target area and the dimensions of the tumor, and allowed adjustment of the dosage distribution according to the therapeutic requirement. CONCLUSION: This simple and feasible method allows cost-effect application of IMRT in smaller hospitals.

Humans↗
PubMed2004

[Immunological up-regulation of cyclophosphamide-treated mice by turtle blood extract].

AIM: To explore the effect of turtle blood extract on murine immune system. METHODS: We compared the ratio of CD4(+) helper T cells and CD8(+) T cells, NK cell activity, lymphocyte proliferation stimulated by mitogen and capability of cytokine secretion of cyclosphophamide-treated mice with or without treatment of turtle blood extract. RESULTS: Turtle blood extract-treated mice displayed increased CD4(+) helper T cell population, stronger cytotoxicity of NK cells and enhanced of ConA-induced lymphocyte proliferation. In addition, the capacity of IFN-gamma secretion was dramatically up-regulated in turtle blood extract-treated mice group. CONCLUSION: Turtle blood extract can upregulate the immune function of cyclosphophamide-treated mouse.

Adjuvants, Immunologic↗
PubMed2004

[Influence of FasL overexpression in transgenic mice on the immune regulative function of Sertoli cell].

AIM: To study the influence of FasL overexpression in transgenic mice on the Sertoli cell immune response to testicular infection. METHODS: Ureaplasma urealyticum (UU) was directly injected into bladders of FasL transgenic mice and wild-type mice respectively, to mimic an ascending infection pathway. At week 1, 2 and 3 after injection, respectively, the mice were put to death to observe the pathological alterations in testis section. And at the same time the differences of FasL, TGF-beta, IL-1alpha and IL-6 expressions on Sertoli cells were compared by immunohistochemical staining between wild mice and transgenic mice before and after infection, respectively. The high-purified Sertoli cells were isolated from the testis tissue of wild-type mice, comparing apoptotic capability of Fas(+) Jurkat cells mediated by FasL(+) Sertoli cells of wild control and wild UU-infected groups. RESULTS: The pathological changes of testis tissue from transgenic mice were more serious as compared with wild-type mice and the model of cytokines secreted by sertoli cells was distinctive between the two kinds of mice. The UU-infected Sertoli cells increased Fas(+) Jurkat cell apoptosis. CONCLUSION: FasL overexpression can influence the cytokine's secretion in the process of anti-infection immunity and further affects the immune balance of testis locality. Not all FasL over expression is benefit to body's anti-infection immune response.

Animals↗