STUDIES ON LIPOSOMAL FERROMAGNETIC PARTICLES AND A TECHNIQUE OF HIGH FREQUENCY INDUCTIVE HEATING

在将铁磁粒子注入肿瘤后，通过施加高频感应加热，可以更有选择性地加热肿瘤。为了设计一种高频感应加热选择性热疗肿瘤的技术，我们继续使用脂质体铁磁颗粒（HP-LM）进行基础研究，制备方法如下：将四氧化三铁（Fe_3 O_4）颗粒包裹在含有具有肿瘤亲和性的血卟啉的脂质体膜上。兔子体内研究：我们使用高频感应加热器（日本KOSHUHA株式会社）。YKN-10)，频率：40khz，输出：10okw，线圈直径：90mm。将1.5X10^7的VX-2肿瘤细胞植入兔大腿下部。当植入肿瘤长到直径3cm时，对A-D组进行加热观察。A组：股动脉给药HP-LM 200mg/kg， B组：股动脉给药Fe_3 O_4 100mg/kg， C组：股动脉结扎，D组：不给药，立即加热。A组：HP-LM剂量200mg/kg，加热10分钟，使肿瘤中心温度升高14.8ºC。B组：Fe_3 O_4剂量为100mg/kg，加热10min，使肿瘤中心温度升高10.6℃。C组：结扎股动脉，加热10分钟，肿瘤中心温度升高6.5ºC。D组：非给药时，加热10分钟，肿瘤中心温度升高4.4℃。A组的体温升高明显高于其他组。A组肿瘤中心、边缘毛细血管及肿瘤细胞内可见铁颗粒。由于HP-LM在肿瘤组织上的吸附作用，通过HP-LM的高频感应加热可以获得选择性热疗，因此认为该技术是非常有用的治疗方法。少

The tumor can be more selectively heated by applying of high frequency inductive heating after administration of ferromagnetic particles into a tumor. In order to devise a technique used for the selective hyperthermia of a tumor with high frequency inductive heating, we continued fundamental studies using liposomal ferromagnetic particles (HP-LM), which were prepared as follows: triiron tetoraoxide (Fe_3 O_4) particles were coated with liposomal membrane contained hematoporphyrin with neoplastic affinity.In Vivo Studies of Rabbits: We used high frequency inductive heater (NIHON KOSHUHA CO. LTD. YKN-10), frequency: 4OOKHz, out put: 1OKw, coil diameter: 90mm. VX-2 tumor cells at 1.5X10^7 were implanted to the lower thigh of rabbit. When the implanted tumor grew up 3cm in diameter, A-D group were heated and studied.Group A: In a dose of 200mg/kg of HP-LM was administrated into the femoral artery, Group B: In a dose of 100mg/kg of Fe_3 O_4 was administrated into the femoral artery, Group C … More : Ligation of femoral artery, Group D: Nonadministrated, and then was immediately heated.Group A: In a dose of 200mg/kg of HP-LM, with heating for 10 minutes, temperature was elevated 14.8ﾟC at center of tumor. Group B: In a dose of 100mg/kg of Fe_3 O_4, with heating for 10 minutes, temperature was elevated 10.6ﾟC at center of tumor. Group C: In a ligation of femoral artery, with heating for 10 minutes, temperature was elevated 6.5ﾟC at center of tumor. Group D: In nonadministration, with heating for 10 minutes, temperature was elevated 4.4ﾟC at center of tumor. Temperature elevation of Group A was significantly higher in comparison with those found in another group. In histological features in Group A, iron particles were stained in blood capillaries at center and edge of tumors, and in tumor cells.It was thought that this technique is very useful treatment, because selective hyperthermia could be obtained by high frequency inductive heating of HP-LM, as a result of adsorption of HP-LM to tumor tissue. Less