| l.To synthesize HSA-(Gd-DTPA)18-19 and to investigate the effects on the coupling efficiency of HSA-DTPA from different reaction conditions.2.To investigate the signal time course of the MR lymphography after interstitial administration of HSA-(Gd-DTPA)18-19 in healthy New Zealand White Rabbits.3.The reactive hyperplasia and metastatic popliteal lymph node models, in New Zealand White Rabbits, were developed to investigate the potential value of the MR lymphography after interstitial administration of HSA-(Gd-DTPA)18-19 and Gd-DTPA to differentiate metastatic from benign lymph nodes, and the efficacy of two kinds of contrast medium in MR lymphography was compared. [Materials and Methods]The synthesis of HSA-(Gd-DTPA)18-191,Preparation of GdCl3725.0 mg Gd203 was added into 200ml 0.1M HC1 and then heated up to 60℃ for 10 minutes, and the product was divided into 4 equal portions.2,The synthesis of HSA-(Gd-DTPA)18-19-7-(1) 660.0mg and 330.0mg HSA were added into 20 ml and 10 ml 0.1M NaHCO3 buffer solution respectively.(2)714.0mg cDTPAa was divided into 2 equal portions and suspended in DMSO.(3) The cDTPA and HSA solution was mixed at DTPA-HSA molar ratio of 200:1 and 100:1 respectively and then was divided into 2 equal portions and the reaction was undergoing in buffer solutions of different pH values(6.0 and 8.0) at room temperature for 30 minutes respectively.(4) GdCl3 was then added into the reaction mixture and lminues later the HSA-(Gd-DTPA)18-19 was purified by exhaustive dialysis.(5) The concentration of Gd was determined and the number of HAS-coupled Gd3 was calculated, and then the coupling efficacy of HSA-DTPA was calculated.MR lymphography after interstitial administration ofHSA-(Gd-DTPA)18-191,Animals:20 male New Zealand White Rabbits weighted at 2.0~2.5kg were used. Every popliteal lymph node served as one independent sample, the total number of sample being 40, and all the lymph nodes were divided into 3 groups at random: normal group, reactive hyperplasia group and tumor-bearing group.2,The development of models:(1) Reactive hyperplasia lymph node model: Ten reactive hyperplasia popliteal lymph nodes were developed by intramuscular injection of 0.5 ml egg yolk emulsion, which was made up of fresh egg yolk and sterile 0.9% saline at the ratio of 1:1, into the lateral upper hind limb of New Zealand White Rabbits.(2) Metastatic lymph node model: A certain quantity of fresh tumor tissue was obtained from the tumor-bearing rabbit and was skived for 5~10minutes in a little sterile 0.9% saline to prepare thetumor cell suspension. And tumor-bearing lymph node model were developed by intramuscular injection of 0.5 ml tumor cell suspension into the lateral upper hind limb of 10 New Zealand White Rabbits.3,Signal-time course study: Two sequences of MR images (T1WI and T1WI FS) were obtained before and at 3hr, 6hr, 12hr, 24hr and 48hr after interstitial administration of HSA-(Gd-DTPA)18-19, at a dose of 0.04mmol Gd/kg , into the interdigital skin fold at the bilateral hind foot. And the signal intensity was measured respectively on two sequences of images and the enhancement ratio was calculated to draw the curve of the enhancement effect over time. And the size of each popliteal lymph node was measured on T1WI FS images.4,MR lymphography imaging:(l)Gd-DTPA group: Four sequences of MR images (T1WI, T1WI FS, PDWI and T2WI) were obtained before and 10 minutes after interstitial administration of Gd-DTPA, at a dose of 0.08mmol Gd/kg, into the interdigital skin fold at the bilateral hind foot.(2) HSA-(Gd-DTPA)18-19 group: Four sequences of MR images T1WI, T1WI FS, PDWI and T2WI) were obtained before and 24hr after interstitial administration of HSA-(Gd-DTPA)18-19, at a dose of 0.04mmol Gd/kg, into the interdigital skin fold at the bilateral hind foot.The enhancing characteristics of all popliteal lymph nodes on 4 sequences of images were analyzed. The signal intensity of all lymph nodes and muscle was measured on 4 sequences of images res...
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