Experimental Study On The New Type Embolization Agent Of Thermosensitve Poly Nanogel

Part oneStudy on the Characteristics of Thermosensitve Poly NanogelObjective To study the correlation properties of thermosensitve poly (N-isopropylacrylamide- co-butyl methacrylate) nanogel and the efficacy, safety andcorrelative characteristics as a vascular embolization agent.Materials and methods Related characteristics of thermosensitve poly nanogel werestudied. Extra corporeal simulation experiments and hepatic arterial embolization of 10rabbits were performed with thermosensitve poly nanogel respectively, others 10 rabbitsembolized with Normal saline as a control.Results Thermosensitve poly nanogel is a thermosensitive embolic material in liquid statewith fine fluidity at room temperatrue, fully solidifies at 37℃and loses fluidity, having ahigh thixotropy and being easily injected through all sorts of interventional catheters andthe embolization agent has hemo-compatibility and good histocompat- ibility, withoutpyrogenetic response and toxicity. Thermosensitve poly nanogel mainly embolized theperipheral arteries. Slight injuries of normal hepatic tissues with hepatic cytonecrosisandendochyloma focal necrosis were found through electronic microscopy.Conclusion Thermosensitve poly nanogel is a safe and effective peripheral embolizationagent in experimental application and a and may be confirmed in further animalexperiments. Part twoThe Animal experimental study On the Vascular Embolization Agent ofThermosensitve Poly Nanogelobjective To emblazc the right renal artery and the hepatic arterial of rabbits withthermosensitve poly nanogel and investigate its feasibility as a vascular embolization agent.Materials and methods To emblize the right renal artery the hepatic arterial of 60 rabbitswith thermosensitvc poly nanogel, PVA as a control. General condition, survival time,hepatic and renal function and pathological changes of the rabbits treated byThermosensitve poly nanogel were performed. Follow-up angiography was performed forembolic efficacy.Results Thermosensitve poly nanogel which easily injected through all sorts ofinterventional catheters is a thermosensitive embolic material. The spirit, drink, eating,hepatic function were normal after embolization and renal function could get normal after14 days. Thermosensitve poly nanogel could emblize arteries at all levels according toexperimental need and could emblaze the periphcral arteries firmly with maintainingocclusion for over one month without pyrogenetic response and toxicity. Pathologically,infarction of renal tissuc was found 3 days after the right renal were embolized,whilehepatic tissue necrosis was found 14days after the hepatic were embolized and diffusenecrosis of renal and hepatic tissue was found 35 days after operation.Conclusion Thermosensitve poly nanogel is a safe and convincnt embolization agentwith good angiocmbolic function and is an ideal vascular embolization agent. Part threeTreatment effect of Thermosensitve Poly Nanogel for Rabbit VX2transplanted hepatocarcinoma modelTest 1 Establishing Rrabbit transplanted VX2 hepatocarcinoma modelfor study of Vascular embolization agentObjective To establish the rabbit VX2 hepatocarcinoma model and study the features ofimaging and pathology examination.Materials and methods Fifty Newzealand rabbits hepatocarcinoma model wereestablished by VX2 tumor implantation, Digital subtraction angiography(DSA), magneticresonance imaging(MRI), computed tomography(CT) scanning and Pathology wereperformed 13 days after implantation.Result Succecssful implantation was obtained in 38 rabbits by the examination ofMRI.The imagology and pathology are all similar with human hepatocarcinoma.Conclusion Rabbit VX2 heptocarcinoma model is suitable for interventional experimentstudy of the vascular embolization agent of thermosensitve poly nanogel onhepatocarcinoma.Test 2 Treatment effect of Thermosensitve Poly Nanogel for Rabbit VX2transplanted hepatocarcinoma modelobjective To observe the inhibiting effect of thermosensitve poly nanogel on rabbit VX2transplanted hepatocarcinoma model through emblazing hepatic artery. Materials and methods 45 rabbits hepatoma model were established by VX2 tumorimplantation.The tumor volume (V1) was measured by magnetic resonance imaging 13days after implantation, then the rabbits were splited randomly into three group(n=15).Andafter 14 days thermosensitve poly nanogel 0.6ml,ultrofluid lipiodol 0.6ml and 0.25mggelfoam spong, Normal saline 1 ml were infused though hepatic artery respectively. Afteranother 14days MRI were performed once again to determine the tumor volume and Thetumor growth rates of three groups were compared. Gross specimen were performedfirstly, including tumor size, necrosis, hemorrhage and liver surface metastases and thearrangement of tumor cells, necrosis and intrahepatic metastasis were observed throughhistological observation under a microscope.Results Average tumor volume of the three groups before operation were0.068±0.11cm~3, 0.071±0.23 cm~3, 0.069±0.19 cm~3, while after operation, average tumorvolume of the three group were 0.289±0.18cm~3, 1.018±0.21cm~3, 4.290±0.67cm~3, Significantdifference existed in growth rates among 3 groups (p＜0.01) and between eithergroups(p＜0.01); Significant difference existed in metastasis of livers 1cm around tumoramong 3 groups (p＜0.01), but not between B and C (p＞0.05).Conclusion Arterial Embolization of thermosensitve poly nanogel had markedinhibitory effect on rabbit VX2 transplanted hepatocarcinoma, and is an ideal embolizationagent for hepatocarcinoma.