The Experimental Research Of The Treatment Of Echinococcus Granulosus In Vitro Using Multi-frequency Focused Ultrasound

Objective To observe the damage status of cyst wall and the change of the permeability of Echinococcus granulosus(E.g) in vitro after irradiated with single-frequency and multi-frequency focused ultrasound.Methods 1: The effect of Multi-frequency focused ultrasound (MFU) on the status of cyst wall of Echinococcus granulosus: Mice were inoculated with echinococcus protoscolice from infected sheep. The mice were sacrificed after one year and the cysts, which diameter reached to 2cm, were selected and divided randomly into 4 groups. Group 1 was control group, after the wall of the cysts which were picked out from the abdominal cavity were cut open, fixed them by 3% glutaraldehyde solution and froze at once. Group 2-4 were experimental groups in which group 2 was monofrequency and was irradiated with transducer No.2(4w). Group 3 was double frequency and treated with transducer No.2(4w) and No.3(5w) jointly. Group 4 was tri-frequency and irradiated with transducer No.1(4w), No.2(4w) and No.3(5w) jointly. After each group irradiated by high intensity focused ultrasound with single-frequency or multi-frequency for 1 minute, the cysts were fixed and refrigerated immediately. The changes of the cyst wall were viewed by naked eyes, transmission electronic microscopy and scanning electronic microscopy. 2: The effect of Multi-frequency focused ultrasound (MFU) on the permeability of cyst wall of Echinococcus granulosus: The hydatid cysts of Echinococcus granulosus , having been cultured in RPMI1640, were irradiated by MFU of different frequency and acoustic power. Then the corresponding different medication concentrations in the cysts were measured by high performance liquid chromatography. Also, observing the influences of MFU on medication permeability of cyst wall with single-frequency, triple-frequency and different power, respectively.Results 1: The cyst wall in all of the experimental groups becomes thicker and the color turns into turbid. According to transmission electron microscopy, the damage to the cyst wall got more serious accordingly along with the increase of ultrasonic power and irradiation times. The fiber of laminated layer became thick and disordered. The nucleolus in germinal layer became swollen and broken. The mitochondria were destroyed remarkably and the microvillus got shorter, fractured or even disappeared. Only cell debris and broken nucleolus left in somewhere. Scanning electron microscopy further demonstrated that damage inside and outside the surface of the cyst wall got worse and worse, until the normal structure was completely destroyed at last along with the increase of ultrasound power and irradiation times. 2: Under the same condition, the difference between the medication concentrations in the cysts, after being irradiated by big power of MFU with triple-frequency and single-frequency, have statistical significance (P<0.05). The medication concentration in the cysts was higher in the group which was irradiated for twice than the group which was irradiated for once (P<0.05). Conclusion Damage from the irritation of multi-frequency MFU to the cyst wall of Echinococcus granulosus in vitro is obvious and the damage status will become worse along with the increase of the ultrasound power and irradiation times; and MFU can increase the medication permeability of cyst wall of Echinococcus granulosus. The medication permeability was in some degree related with different irritating power. The medication permeability of cyst wall was higher after the cystwas irradiated for several times than that was only irritated for once.