Publications by authors named "Chung-Boo Kang"

Several lines of prion protein gene (Prnp)-knockout mice such as ZrchI, ZrchII, Npu, Ngsk and Rcm0 have been generated. Of these, ZrchII, Ngsk and Rcm0 exhibit late-onset ataxia due to ectopic expression of Doppel (Dpl); a result of damage to the splicing acceptor of Prnp exon 3. Recently, we developed another line of Prnp-/- mice (Rikn), which was generated by gene targeting with more nucleotides by replacing intron 2 with the pgk-neo gene (cf.

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Splenocytes of wild-type (Prnp(+/+)) and prion protein gene-deficient (Prnp(-/-)) mice were treated with various activation stimuli such as T cell mitogen concanavalin A (ConA), phorbol 12-myristate 13-acetate (PMA)+ionomycin (Io), or B cell mitogen lipopolysaccharide (LPS). Cellular prion protein (PrP(C)) expression was enhanced following ConA stimulation, but not PMA+Io or LPS in Prnp(+/+) splenocytes. Rikn Prnp(-/-) splenocytes elicited lower cell proliferations than Prnp(+/+) or Zrch I Prnp(-/-) splenocytes after LPS stimulation and showed sporadic nerve cells in the cerebral cortex and deeper structure.

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A sugar cane extract (SCE) has been found to have an immunostimulating effect in several animals. Lipopolysaccharide (LPS) is known to induce endotoxin shock via the production of inflammatory modulators such as tumor necrosis factor (TNF)-alpha and nitric oxide (NO). We examined in the present study the effects of SCE on the TNF-alpha and NO production in LPS-stimulated mice peritoneal cells and the endotoxin shock in mice.

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The phagocytic activity of peripheral blood leukocytes (PBL) in chickens orally administered sugar cane extracts (SCE) or polyphenol-rich fraction (PRF) of SCE (500 mg/kg/day) for 3 consecutive days increased significantly, when compared with that of saline-administered control chickens. Chickens orally administered SCE or PRF (500 mg/kg/day) for 3 consecutive days showed significantly higher antibody responses against sheep red blood cells and Brucella abortus than control chickens. In addition, oral administration of SCE or PRF also resulted in a significant increase in the number of IgM- and IgG-plaque forming cell responses of PBL, intestinal leukocytes and splenocytes, when compared with those of control chickens.

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Synthetic peptides, peptides A (Arg-Leu-Tyr-Leu-Arg-Ile-Gly-Arg-Arg-NH(2)) and B (Arg-Leu-Arg-Leu-Arg-Ile-Gly-Arg-Arg-NH(2)), derived from the beetle Allomyrina dichotoma defensin, have antimicrobial activities. Immunotoxicological effect of these peptides was evaluated by cytotoxicity of mouse peritoneal macrophages. In addition, antigenicity of these peptides was studied by evaluating antibody responses in mice immunized with these peptides.

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Thimerosal is one of the most widely used preservatives and is found in a variety of biological products, including vaccines, contact lens cleaning solutions, and cosmetics. It has been reported to have harmful effects on epithelial tissues, such as causing conjunctivitis or contact dermatitis. However, the molecular mechanism of its toxicity has not been characterized using epithelial tissues.

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Sugar cane extract (SCE) has been shown to have an immunostimulating effect in chickens. This study evaluated the effect of SCE on Salmonella Abortusequi lipopolysaccharide (LPS)-induced lethal shock in d-galactosamine (GalN)-sensitized mice. Mice were administered intraperitoneally SCE (500 mg/kg) or phosphate buffered saline before or after injection of LPS and GalN.

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The occurrence of Bovine Spongiform Encephalopathy (BSE, so called mad cow diseases) that was first identified in England in 1986 was considered as being limited to only European countries, including England. However, the outbreak in Asia as well as North America since 2001 has amplified the fear that there isn't any nation in the world that is a safe area. In order to assess the risk of BSE outbreak in each country, the Office International des Epizooties (OIE) and EU have respectively established criteria, where OIE has set 5 levels and EU has set 4 levels.

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Polymorphonuclear cells of the peripheral blood in the chicken significantly increased their phagocytosis when cultured with sugar cane extract (SCE; 250-1,000 microg/ml) for 24 hr. Chickens orally administered SCE (500 mg/kg/day) for 3 or 6 consecutive days at 1 week of age showed significantly higher body weight and gain in body weight/day and a lower food conversion ratio within the growing period of 6 weeks than physiological saline-administered control chickens. Furthermore, oral administration of SCE also resulted in significantly higher immune responses against sheep red blood cells and Brucella abortus.

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