• Korean Journal of Veterinary Pathology
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• v.2 no.2
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• pp.73-84
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• 1998

This study was carried out to investigate on the serum chemistry and the DNA ploidy changes in carcinogenesis of the rat liver and kidney. Sixty male Sprague-Dawley rats were divided into two groups. Group I was non-treated control. Group II was given initiators (2,2'-dihydroxy- di-N-propylnitrosamine, 0.1% in drinking water(d.w.) for 1 week and N-ethyl-N-hydroxy-ethylnitrosamine; 0.15% in d.w. for 1 week) and promoters (3'methyl-cholanthrene; 3'MC, l0mg/kg, intraperitoneally(i.p.) twice a week and DL-serine; 0.05% in d.w. for 5 weeks, from 3 to 8 weeks). All examinations were performed at 12 and 20 weeks RBC, HGBCp＜0.05) and PCVCp＜0.01) significantly decreased in Group II at 20 weeks. Activities of ALT, AST(p＜0.05) and GGT(p＜0.01) were significantly increased in Group II at 20 weeks. Flow cytometric analysis showed hepatocyte nuclei from normal livers were predominantly tetraploid(66~67%) and then diploid(28~30%). Most of hepatocyte nuclei from carcinogen-treated rats were diploid (52~68%) and less were tetraploid(28~42%). Neoplastic liver nodules and hepatocellular carcinoma contained almost exclusively diploid nuclei. Renal cell nuclei from normal kidney were predominantly diploid(88~93%), those from carcinogen-treated rats had an abnormal DNA-content peak(aneuploidy, 6-7%), near the tetraploidy area. These results suggest that diploidy may be an effective screening marker of the liver carcinogenesis. Aneuploidy may be an useful marker in assessment of the experimental renal carcinogenesis.

• The Korean Journal of Nuclear Medicine
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• v.38 no.3
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• pp.253-258
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• 2004

Purpose: Chitosan has been studied as a non-viral gene delivery vector, drug delivery carrier, metal chelator, food additive, and radiopharmaceutical, among other things. Recently, galactose-graft chitosan was studied as a non-viral gene and drug delivery vector to target hepatocytes. The aim of this study was to investigate the usefulness of nuclear imaging for in vivo evaluation of targeting the hepatocyte by galactose grafting. Methods and Materials: Galactosyl methylated chitosan (GMC) was produced by methylation to lactobionic acid coupled chitosan. Cytotoxicity of $^{99m}Tc$-GMC was determined by MTT assay. Rabbits were injected via their auricular vein with $^{99m}Tc$-GMC and $^{99m}Tc$-methylated chitosan (MC), the latter of which does not contain a galactose group, and images were acquired with a gamma camera equipped with a parallel hole collimator. The composition of the galactose group in galactosylated chitosan (GC), as well as the tri-, di-, or mono-methylation of GMC, was confirmed by NMR spectroscopy. Results: The results of MTT assay indicated that $^{99m}Tc$-GMC was non-toxic. $^{99m}Tc$-GMC specifically accumulated in the liver within 10 minutes of injection and maintained high hepatic uptake. In contrast, $^{99m}Tc$-MC showed faint liver uptake. $^{99m}Tc$-GMC scintigraphy of rabbits showed that the galactose ligand principally targeted the liver while the chitosan functionalities led to excretion through the urinary system. Conclusion: Bioconjugation with a specific ligand endows some degree of targetability to an administered molecule or drug, as in the case of galactose for hepatocyte in vivo, and evaluating said targetabililty is a clear example of the great benefit proffered by nuclear imaging.