The method of preparing uniform dextran microspheres with a narrow diameter distribution was introduced and the adsorbability of these microspheres was evaluated.The microspheres were prepared in W/O microemulsion usi...The method of preparing uniform dextran microspheres with a narrow diameter distribution was introduced and the adsorbability of these microspheres was evaluated.The microspheres were prepared in W/O microemulsion using 0.5% dextran solution as the aqueous phase and n-hexane as the oil phase.Characteristics of the prepared dextran microspheres were examined with laser light blocking technique,optical microscope and ultraviolet spectrometer.The results show that the prepared dextran microspheres have uniform morphology and narrow diameter distribution,nearly 92% of them having a diameter of 56.6 μm.In vitro evaluation of adsorbability,wet dextran microspheres have good adsorption of 98.32 mg/g of model drug methylene blue in 20.86 mg/L methylene blue solution at 25℃.The adsorption of dried dextran microspheres under the same condition is 132.15 mg/g,which is even higher.And the adsorbability of dextran microspheres has significant relationship with the concentration of methylene blue and temperature.The adsorbability is better at lower temperature and higher concentration of methylene blue.展开更多
Objective To evaluate the therapeutic effect and the mechanism of dextran microsphere hepatic artery embolization for hepatoma. Methods Partial hepatectomy was performed in 11 patients with hepatoma pretreated wit...Objective To evaluate the therapeutic effect and the mechanism of dextran microsphere hepatic artery embolization for hepatoma. Methods Partial hepatectomy was performed in 11 patients with hepatoma pretreated with dextran microsphere hepatic artery embolization. All specimens were for histopathologic studies in order to observe the destiny of dextran microspheres and necrotic degree of the tumor. Results complete necrosis of the tumor was found in seven cases and incomplete necrosis of the tumor in the rest 4. Tumors in the later were near to areas rich in arterial collateral anastomoses. The extent of tumor necrosis was unrelated to the presence and thickness of tumor capsule and capsular invasions. Dextran microspheres could cause permanent embolization of distal arterioles. The microspheres were very biocompatible and cause little foreign body reaction. No inflammatory changes were seen both inside and outside of the embolized artery 191 days after embolization. Dextran microspheres were not absorbed and the vessel recanalization was also not seen. Dextran microsphere was not found in portal veins. Conclusion Some hepatomas distant from the collateral circulation of arteries could be cured with dextran microsphere hepatic artery embolization alone.展开更多
文摘The method of preparing uniform dextran microspheres with a narrow diameter distribution was introduced and the adsorbability of these microspheres was evaluated.The microspheres were prepared in W/O microemulsion using 0.5% dextran solution as the aqueous phase and n-hexane as the oil phase.Characteristics of the prepared dextran microspheres were examined with laser light blocking technique,optical microscope and ultraviolet spectrometer.The results show that the prepared dextran microspheres have uniform morphology and narrow diameter distribution,nearly 92% of them having a diameter of 56.6 μm.In vitro evaluation of adsorbability,wet dextran microspheres have good adsorption of 98.32 mg/g of model drug methylene blue in 20.86 mg/L methylene blue solution at 25℃.The adsorption of dried dextran microspheres under the same condition is 132.15 mg/g,which is even higher.And the adsorbability of dextran microspheres has significant relationship with the concentration of methylene blue and temperature.The adsorbability is better at lower temperature and higher concentration of methylene blue.
基金This project was supported by a grant from NationalNatural Science Foundation of China (No 39770 35 5)
文摘Objective To evaluate the therapeutic effect and the mechanism of dextran microsphere hepatic artery embolization for hepatoma. Methods Partial hepatectomy was performed in 11 patients with hepatoma pretreated with dextran microsphere hepatic artery embolization. All specimens were for histopathologic studies in order to observe the destiny of dextran microspheres and necrotic degree of the tumor. Results complete necrosis of the tumor was found in seven cases and incomplete necrosis of the tumor in the rest 4. Tumors in the later were near to areas rich in arterial collateral anastomoses. The extent of tumor necrosis was unrelated to the presence and thickness of tumor capsule and capsular invasions. Dextran microspheres could cause permanent embolization of distal arterioles. The microspheres were very biocompatible and cause little foreign body reaction. No inflammatory changes were seen both inside and outside of the embolized artery 191 days after embolization. Dextran microspheres were not absorbed and the vessel recanalization was also not seen. Dextran microsphere was not found in portal veins. Conclusion Some hepatomas distant from the collateral circulation of arteries could be cured with dextran microsphere hepatic artery embolization alone.
