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Objective To investigate the effects of pulsed magnetic fields of different intensity on carotid restenosis (CRS), post carotid endarterectomy (CEA) and the expression of matrix metalloproteinase-2 (MMP-2)in vascular smooth muscle cells (VSMC). Methods An animal model of carotid altherosclerosis was established in 50 New Zealand rabbits by using air-drying lesions combined with high fat feed. After two months, the rabbits were treated with bilateral CEA, and then divided randomly into 3 groups. Two of the groups were treated with ei-ther 0.6 or 1.0 T pulsed magnetic fields, while the third group served as an untreated blank control. Changes in the pathology of the tunica intima were observed 1, 2 and 3 months after the CEA using morphologic analysis, and the expression of MMP-2 in the VSMC was determined using immunohistochemistry. Results The histological a-nalysis showed that the total luminal area, plaque area, the maximum plaque thickness and the proportion of siena-sis in the treated groups were all significandy lower, on average, than in the control group. At all three time points the average improvements in the 1.0 T group were significantly greater than in the 0.6 T group. The average ex-pression of MMP-2 in the treated groups was significantly lower than in the control group, especially in the 1.0 T group. Conclusions Pulsed magnetic field therapy positively influences CRS and the expression of MMP-2 in VSMC. Reduced MMP-2 expression might be one of the mechanisms through which pulsed magnetic fields prevent or lessen carotid restenosis post CEA.
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@#Objective To investigate the effect of different dosage of pulsed magnetic field on expression of platelet-derived growth factor-A (PDGF-A) in rabbits with carotid atherosclerosis after carotid endarterectomy (CEA). Methods Carotid atherosclerosis were modeled in 50 New Zealand rabbits with air-drying lesion combined with high fat feed. All animals were treated with double side carotid endarterectomy after 2 months, and were randomly divided 3 groups: 0.6 T group, 1.0 T group and the blank control. The expression of platelet-derived growth factor-A were detected with immunohistochemistry 1 month, 2 months and 3 months after CEA. Results The expression of PDGF-A in treated groups were lower significantly than that in controls (P<0.05) 2 month after CEA, and it was the lowest in 1.0 T group, lower in 0.6 T group 3 month after CEA. Conclusion The pulsed magnetic field therapy can decrease the expression of PDGF-A, which might be helpful to prevent the carotid from restenosis.
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@#Objective To observe the changes of neural blood flow when oppressed with different pressures and at different sites in rat's sciatic nerve.MethodsThe sciatic nerve compression model of rat with pressure and time controlled simultaneously was established.The changes of neural blood flow were observed by oppressing the sciatic nerve with five grades pressures using Gasbag.The rats were randomly divided into the distal compression group and proximal compression group,and the changes of neural blood flow were observed in each group.ResultsThe neural blood flow changed significantly(P<0.05) when the sciatic nerve was oppressed with different pressures and it had the decreasing tendency with the pressures increasing.The neural blood flow of each group decreased obviously(P<0.01).The effect of oppressing distal nerve on neural blood flow was more obvious than that of oppressing proximal nerve(P<0.01).ConclusionMechanical compression can influence the neural blood flow obviously.The distal vessels of sciatic nerve are the major sources of nerve blood supply.
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Objective To establish intra-body communication(IBC)model with quasi-static approximation and validate its correctness.Methods The quasi-static approximation conditions of human tissues were discussed.Based on the Maxwell Equations,the model of galvanic coupling IBC was developed analytically.It was assumed that the human forearm was equal to column with a pair of ring electrodes.Sausage column was selected to be the experimental object for validating the correctness of the model.Results Galvanic coupling IBC model was established.The deviation of model calculated results from test measured potentials was less than 10%,and the correlation coefficient was more than 0.998.The potential distribution and attenuation were depicted with the model.Conclusion Under quasi-static approximation condition the galvanic coupling IBC electromagnetic theoretic model is developed and validated.It is provided the preliminary theoretic base on IBC technique.
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The titer of Interleukin-2 (IL-2), prepared from the healthy human peripheral blood lymphoytes which were stimulating-induced by carboxymethy-parchymaran (CMP), was very high and reached clinical drug level after special process. The IL-2 was not only available for intramuscular injection. but also for intravenous in jection or even for intraarterial, injection 44 partients with advanced malignant tumor treated with the combination of IL-2 / LAK and chemotherapy showed an overall objective response rate to 86. 4% (CR + PR: 13, 29.3%); (CR + PR + MR: 22, 50%); (CR + PR + MR + SR : 38, 86. 4%) . 37 Patients with various malignant tumors were treated by low-dose interleukin-2 stinulated with CMP and irradiation with 60Co. The percentages of CR, PR and SR were 51.4%, 46.8%and 2.7%, respectively. Overall effectiveness rate was 97.3%. 1 year survival rate was 86.2%. 16 Patients with various advanced cancers were treated by low-dose interleukin-2 stimulated with CMP and low - dose radiotherapy or chemotherapy. The percentage of CR, PR and SR was 37. 5%, 56. 3%and 6 . 3%, respectively. Overall effective rate was 93. 8%. 1 year survival rate was 87. 5%. The current results indicate that the possibility of combined therapy of the low - dose IL-2/LAK adoptive chemoimmunotherapy and radiotherapy or chemotherapy may be effective in treatment of advanced cancer.