A phenomenological model for the dynamics of cell cycle in responding to X-rays / 中华放射医学与防护杂志

Objective To establish a model to predict the cell-cycle process in response to ionizing radiation.Methods Human choroidal malignant melanoma 92-1 cells were used and the cell cycle distribution of cells was analyzed in 0-96 h after exposure to X-rays.A phenomenological model was constructed based on biological knowledge to describe the cell cycle dynamics in experiments.Results In the present study,a phenomenological model was constructed to describe the cellcycle dynamics of synchronized 92-1 cells in responding to various doses of ionizing radiation.The simulation results obtained with the model were consistent with the experimental data,demonstrating that the model had a good expansibility and could be used to predict the dynamics of cell cycle in responding to ionizing radiation.Further theoretical modeling of the cellcycle dynamics was made and the results were consistent with the simulation.Conclusions A phenomenological model was constructed which could be used to describe the dynamics of cell cycle of cells exposed to ionizing radiation and was supported by the experimental data.Because this model is easy to run by the written code,it has a good expansibility for studying the behaviors of cell populations under various conditions.

Expression of costimulatory molecules on peripheral blood lymphocytes of patients with idiopathic thrombocytopenic purpura / 中华血液学杂志

<p><b>OBJECTIVE</b>To investigate the expressions of costimulators on peripheral T and B lymphocytes in patients with idiopathic thrombocytopenic purpura (ITP).</p><p><b>METHODS</b>The expression of B7-CD(28) and CD(40) of peripheral lymphocytes was measured by flow cytometry in 21 ITP patients and 9 normal subjects. The expression of PAIgG was measured by ELISA method.</p><p><b>RESULTS</b>The expression of CD(4)(+)CD(28)(+) was lower in ITP patients than in normal controls, but the expression of CD(86)(+) and CD(86)(+)CD(19)(+) was higher in ITP patients than in normal controls, while the expression of CD(80)(+), CD(40)(+), CD(28)(+), CD(19)(+)CD(86)(+), CD(19)(+)CD(40)(+), CD(4)(+)CD(28)(+)/CD(4)(+), CD(19)(+)CD(80)(+)/CD(19)(+) and CD(19)(+)CD(40)(+)/CD(19)(+) in ITP patients was normal. The PAIgG level was higher in 16 patients with a mean of (184.62 +/- 38.00) ng/10(7) plt. A positive correlation was found between PAIgG and CD(19)(+)CD(86)(+)/CD(19)(+) expression.</p><p><b>CONCLUSION</b>There is no deficiency in expression of CD(28) on CD(4)(+) T lymphocytes in ITP patients. The change of CD(86) expression on B lymphocytes is possibly involved in pathophysiology of ITP, which may provide a theoretical instruction for ITP patients immunological therapy.</p>