We study target-searching processes on a percolation, on which a hunter tracks a target by smelling odors it emits. The odor intensity is supposed to be inversely proportional to the distance it propagates. The Monte ...We study target-searching processes on a percolation, on which a hunter tracks a target by smelling odors it emits. The odor intensity is supposed to be inversely proportional to the distance it propagates. The Monte Carlo simulation is performed on a 2-dimensional bond-percolation above the threshold. Having no idea of the location of the target, the hunter determines its moves only by random attempts in each direction. For lager percolation connectivity p (＞～) 0.90, it reveals a scaling law for the searching time versus the distance to the position of the target. The scaling exponent is dependent on the sensitivity of the hunter. For smaller p, the scaling law is broken and the probability of finding out the target significantly reduces. The hunter seems trapped in the cluster of the percolation and can hardly reach the goal.展开更多
To investigate the effects of overall alkali of a traditional Chinese medicine “Tongbiling” (brucine and strychnine alkaloids in main) on the cytokines expression in Th1 and Th2 cells in the synovial fluid of patien...To investigate the effects of overall alkali of a traditional Chinese medicine “Tongbiling” (brucine and strychnine alkaloids in main) on the cytokines expression in Th1 and Th2 cells in the synovial fluid of patients with rheumatism arthritis and their signal pathway, the mononuclear cells in the synovial fluid (SFMC) of patients were isolated by Ficoll-Hypaque gradient centrifugation, and the CD3 + CD69 + and CD3 + HLA-DR antigen were analyzed by flow cytometry in comparison with those of the peripheral blood. The rest of cells were cultured after resuspension with RPMI 1640 culture medium. Phorbol 12,13-dibutyrate (PDB) and ionomycin were added successively into the culture with various concentration of overall alkali Tongbiling (TBL). After 4 h of cultivation, the expression of IFN-γ and IL-4 in CD3 + cells were analyzed by flow cytometry. The influence of overall alkali TBL (100?mg/L) on the intracellular calcium was investigated after Fluo-3/AM labeling and stimulation with PDB and ionomycin at 1, 2, 4 and 10?min, and the influence of TBL on the expression of CD3 + CD69 + cells were determined with stimulation of PDB for 24?h in the whole blood lymphocytes culture. It was found that the percentage of T cells bearing CD69 was significantly up-regulated (77%), while that of T cells bearing HLA-DR was 44% in the synovial mononucleated cells. After PDB and ionomycin stimulation, the expression of IFN-γ in CD3 + cells were up-regulated, but there was no change on the expression of IL-4 in CD3 + cells, indicating that ratio of Th1/Th2 was significantly increased and Th cells differentiate to Th1 cells in mainly. Four concentrations of overall alkaloid of TBL (200?mg/L, 100?mg/L, 50?mg/L, 25?mg/L) could down-regulated the expression of IFN-γ in CD3 + cells and the Th1/Th2 ratio obviously, but all the concentrations of the overall alkaloids had no effect on the expression of IL-4 in CD3 + cells. 100?mg/L concentration of the overall alkaloid did not down-regulate the intracellular calcium level. Each concentration of the overall alkaloid could down-regulated the expression CD69 obviously on the PDB-activated mouse T cells. It concluded from the above observations that the overall alkaloid of TBL could relieve the inflammatory and immune damages by suppressing the expression of Th1 type cytokines and Th1 cell differentiation, regulating the imbalance of Th1/Th2 cells and inhibiting the early activation of the T lymphocytes bearing CD69. There was no remarkable influence on the intracellular calcium signaling transduction pathway. The inhibitory effected on T cells to express IFN-γ might be due to the suppression of PKC-MAPK signaling pathway. From the standpoint of traditional Chinese medicine, this might be due to the regulation of “Yin” and “Yang” imbalance of joints to modify the pathological status in rheumatoid arthritis. This study provided an experimental basis for the application of overall alkaloids of TBL in the treatment of rheumatoid arthritis.展开更多
文摘We study target-searching processes on a percolation, on which a hunter tracks a target by smelling odors it emits. The odor intensity is supposed to be inversely proportional to the distance it propagates. The Monte Carlo simulation is performed on a 2-dimensional bond-percolation above the threshold. Having no idea of the location of the target, the hunter determines its moves only by random attempts in each direction. For lager percolation connectivity p (＞～) 0.90, it reveals a scaling law for the searching time versus the distance to the position of the target. The scaling exponent is dependent on the sensitivity of the hunter. For smaller p, the scaling law is broken and the probability of finding out the target significantly reduces. The hunter seems trapped in the cluster of the percolation and can hardly reach the goal.
文摘To investigate the effects of overall alkali of a traditional Chinese medicine “Tongbiling” (brucine and strychnine alkaloids in main) on the cytokines expression in Th1 and Th2 cells in the synovial fluid of patients with rheumatism arthritis and their signal pathway, the mononuclear cells in the synovial fluid (SFMC) of patients were isolated by Ficoll-Hypaque gradient centrifugation, and the CD3 + CD69 + and CD3 + HLA-DR antigen were analyzed by flow cytometry in comparison with those of the peripheral blood. The rest of cells were cultured after resuspension with RPMI 1640 culture medium. Phorbol 12,13-dibutyrate (PDB) and ionomycin were added successively into the culture with various concentration of overall alkali Tongbiling (TBL). After 4 h of cultivation, the expression of IFN-γ and IL-4 in CD3 + cells were analyzed by flow cytometry. The influence of overall alkali TBL (100?mg/L) on the intracellular calcium was investigated after Fluo-3/AM labeling and stimulation with PDB and ionomycin at 1, 2, 4 and 10?min, and the influence of TBL on the expression of CD3 + CD69 + cells were determined with stimulation of PDB for 24?h in the whole blood lymphocytes culture. It was found that the percentage of T cells bearing CD69 was significantly up-regulated (77%), while that of T cells bearing HLA-DR was 44% in the synovial mononucleated cells. After PDB and ionomycin stimulation, the expression of IFN-γ in CD3 + cells were up-regulated, but there was no change on the expression of IL-4 in CD3 + cells, indicating that ratio of Th1/Th2 was significantly increased and Th cells differentiate to Th1 cells in mainly. Four concentrations of overall alkaloid of TBL (200?mg/L, 100?mg/L, 50?mg/L, 25?mg/L) could down-regulated the expression of IFN-γ in CD3 + cells and the Th1/Th2 ratio obviously, but all the concentrations of the overall alkaloids had no effect on the expression of IL-4 in CD3 + cells. 100?mg/L concentration of the overall alkaloid did not down-regulate the intracellular calcium level. Each concentration of the overall alkaloid could down-regulated the expression CD69 obviously on the PDB-activated mouse T cells. It concluded from the above observations that the overall alkaloid of TBL could relieve the inflammatory and immune damages by suppressing the expression of Th1 type cytokines and Th1 cell differentiation, regulating the imbalance of Th1/Th2 cells and inhibiting the early activation of the T lymphocytes bearing CD69. There was no remarkable influence on the intracellular calcium signaling transduction pathway. The inhibitory effected on T cells to express IFN-γ might be due to the suppression of PKC-MAPK signaling pathway. From the standpoint of traditional Chinese medicine, this might be due to the regulation of “Yin” and “Yang” imbalance of joints to modify the pathological status in rheumatoid arthritis. This study provided an experimental basis for the application of overall alkaloids of TBL in the treatment of rheumatoid arthritis.
