• Journal of the Korean Society of Radiology
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• v.10 no.6
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• pp.375-379
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• 2016

A rat is the most common experimental animal used for the realization of the radiation injury model. The certain thickness of rat skin was prepared by peeling off a rat skin. Radiation level was measured by using this rat skin. Also, The schematic of the formula was made that can predict the radiation absorbed dose (RAD) as a function of the thickness of the rat skin. Consequently, we will provide the RAD information in the realization of in-vitro experimental model regarding the rat's skin thickness by applying the formulas. Moreover, the results from this study can be effectively used for the in-vitro experiment of the rat subcutaneous tissue which was exposed to radiation.

• Restorative Dentistry and Endodontics
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• v.37 no.4
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• pp.194-200
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• 2012

Objectives: New resin cement (NRC) has been developed as a root repairing material and the material is composed of organic resin matrix and inorganic powders. The aim of this study was to compare the rat subcutaneous tissue response to NRC and mineral trioxide aggregate (MTA) cement and to investigate the tissue toxicity of both materials. Materials and Methods: Sixty rats received two polyethylene tube-implants in dorsal subcutaneous regions, MTA and NRC specimens. Twenty rats were sacrificed respectively at 1, 4 and 8 wk after implantation and sectioned to 5 ${\mu}m$ thickness and stained with Hematoxylin-Eosin (H-E) or von-Kossa staining. The condition of tissue adjacent to the implanted materials and the extent of inflammation to each implant were evaluated by two examiners who were unaware of the type of implanted materials in the tissues. Data were statistically analyzed with paired t-test (p < 0.05). Results: In specimens implanted with both NRC and MTA, severe inflammatory reactions were present at one wk, which decreased with time. At eighth wk, MTA implanted tissue showed mild inflammatory reaction, while there were moderate inflammatory reactions in NRC implanted tissue, respectively. In NRC group, von-Kossa staining showed more calcification materials than MTA group at eighth wk. Conclusions: It was concluded that the calcium reservoir capability of NRC may contribute to mineralization of the tissues.

• Preventive Nutrition and Food Science
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• v.2 no.3
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• pp.219-224
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• 1997

The pancreas is an important organ in the maintenance of zine homeostasis. The pancreatic tissue used in this study was obtained from rats fed varying levels of dietary Ca nd phytate followed by intraperitoneal {TEX}${65}^Zn${/TEX} injection. THe objective of this study was to determine the molecular size and distribution of compounds that may represent zinc-binding complexes in pancreatic tissue homogenates. The supernatant of the homogenized pancreatic tissue was separated using a Sephadex G-75 column with Tris buffer at pH 8.1. All subfractions were assayed for zinc, protein and {TEX}${65}^Zn${/TEX} activity. The elution of subfractions from pancreatic tissue homogenates showed a prominent peak corresponding to the high molecular weight protein standard (>66kd). A sall molecular weigth protein (<6.5kd), that was absorbed at 280nm, was also present: prominently in low Ca group, however not much as in high Ca group. These small compounds may combine weakly with zinc in pancreatic tissue an serve as zinc-binding ligands in pancreatic/biliary fluid. In the duodenum, these ligands dissociate zinc into an ionic form which becomes vulnerable to phytate complexation.

• Journal of Ginseng Research
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• v.6 no.2
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• pp.123-130
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• 1982

Studies were carried out to clarify the effect of ginsenoside-Rbl -Rbr and acid hydrolyzatps of ginsenoside-Rbl, -Rb2 (HRbl, HRbf) on lipolysis and lipogenesis induced by epinephrine, glucagon, ACTH (adrenocorticotrophic hormone), TSH (thyroid-stimulating hormone) and insulin in rat adipose tissilr. HRbl , HRb2 slightly inhibited lipolysis induced by epinephine. glucagon and TSH. ACTH-induced lipolysis in fat tissue slices was significantly inhibited by ginsenoside -Rbl, -Rb2, HRbl and HRb2, particulary HRb2. None of ginsenoside-Rbl, -Rb2, HRbl and HRb2 accelerated insulin-stimulated lipogenesis in fat calls. Among ginseng products, extract powder (freeze dried), extract powder (spray dried), red ginseng powder inhibited ACTH-induced lipolysis in adipose tissue slices, but red ginseng extract not affect them.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.30 no.4
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• pp.323-332
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• 2008

Aim of the study: Scaffolds are crucial to tissue engineering/regeneration. Biodegradable polymer/ceramic composite scaffolds can overcome the limitations of conventional ceramic bone substitutes such as brittleness and difficulty in shaping. In this study, poly(L-lactide)/hydroxyapatite(PLLA/HA) composite scaffolds were fabricated for in vivo bone tissue engineering. Material & methods: In this study, PLLA/HA composite microspheres were prepared by double emulsion-solvent evaporation method, and were evaluated in vivo bone tissue engineering. Bone marrow mesenchymal stem cell from rat iliac crest was differentiated to osteoblast by adding osteogenic medium, and was mixed with PLLA/HA composite scaffold in fibrin gel and was injected immediately into rat cranial bone critical size defect(CSD:8mm in diameter). At 1. 2, 4, 8 weeks after implantation, histological analysis by H-E staining, histomorphometric analysis and radiolographic analysis were done. Results: BMP-2 loaded PLLA/HA composite scaffolds in fibrin gel delivered with osteoblasts differentiated from bone marrow mesenchymal stem cells showed rapid and much more bone regeneration in rat cranial bone defects than control group. Conclusion: This results suggest the feasibility and usefulness of this type of scaffold in bone tissue engineering.

• Journal of Periodontal and Implant Science
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• v.24 no.1
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• pp.109-119
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• 1994

An essential fact in the regeneration of new periodontal tissue after periodontal therapy is the reattachment of collagen fibers to the tooth. Two phenomena play a fundamental role in preventing new connective tissue attachment to the exposed root surface ; 1) The apical migration of the junctional epithelium 2) The contamination of cementum by toxic substances, especially endotoxins. Authors have used rat submucosal implantation of root sections to study the connective tissue healing to periodontally diseaed root, previously planed and demineralized with citric acid and tetracycline- HCl. The results were obtained as follows. 1. The connective tissue attachment was increased in tetracycline, citric acid, non disease, scaling and root planing order and inflammatory reaction was seen in the rat teeth, no treatment group. 2. Collagen fiber attachment at the dentin surface was more increased than cementum surface 3. In 2 week of citric acid and tetracycline-HCl specimens, osteoid was seen near the fibrotic band. 4. In the MT view, collagen fiber formation was increased with time and the numerous collagen fiber and connective tissue was more densly attached to the tooth surfaces in the tetracycline-HCl group than the citric acid group.

• Archives of Plastic Surgery
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• v.39 no.5
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• pp.452-456
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• 2012

Background Phosphatidylcholine (PPC) and deoxycholate (DCA) compound has been recently used for the purpose of partial lipolysis and is valued for its efficacy and lower invasiveness compared to liposuction and dermolipectomy used previously. In this article, the authors discuss the efficacy of the PPC dissolved in DCA via an experimental rat study model, along with suggesting a useful animal experimental model for the study of adipose tissue and lipolysis. Methods Bilateral inguinal fat pads of an experimental rat were elevated with the deep inferior epigastric vessel as the sole vascular pedicle. Normal saline was injected on one side as a control group and a PPC and DCA compound was injected on the other side. After 4 days, the rats were euthanized for microscopic tissue examination. The pathology was scored by a sem-iquantitative system in 4 categories: normal fat amount, fat necrosis, inflammatory activity, and stage of fibrosis. A Wilcoxon signed-rank test powered by SPSS packet program was used for statistical analysis and to determine significance. Results Microscopic examination was performed on the obtained samples, and the experimental data of all four categories showed significant histologic differences compared to the control group. All of the data also showed statistical significance by the Wilcoxon signed-rank test (P<0.01). Conclusions In the inguinal fat pad rat model, the control group and the experimental group had a differed significantly in the amount of normal fat tissue, inflammation, necrosis, and fibrosis. We recommend the rat inguinal fat pad model used in this study, as it is likely to be useful in related research.

• The Korean Journal of Food And Nutrition
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• v.6 no.1
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• pp.37-46
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• 1993

Brain, heart, liver, lung, kidney and thymus etc. 12 organs were removed and homogenized from Dawley-Sprague rats after suffocation. After fractionation of the tissue cytosols, enzymatic activities of the key enzymes in metabolic inositol phosphates cycle, PLC, IPSK and Ins(1,4,5) P35-phosphatase, were measured respectively. Hybridoma monoclones producing anti-lP3K murine monoclonal antibodies were obtained by the fusion of SP2/Ag 0-14 and spleen cells of mouse immunized with purified 53KDa IPSK, screening and cloning procedures. 18 cloned hybridoma cells were obtained, background due to nonspecific binding was very low with 10 clones. These Abs were purified from ascitic fluids by using affi-gel 15, and determined subtype of Abs. When immunoreactivities for rat tissues IP3K were exercised by adding the mixed Abs of 19Gl and 19G2b, they showed an overall similarity with noncompetitive inhibition. Brain tissue has high sensitivity for anti-lP3K Ab, whereas heart tissue has very low activity. In kinetic parameters Km value was 1.58 mM and Vmx value was 5.41umol/min/ml, respectively Only one form of 40 KDa IPSK was detected in heart tissues, however rat brain contains at least three immunologically distinct IP3K (53, 51 and 40 KDa) in western blot analysis. Of them 53 KDa protein was major enzyme in enzymatic activity. Northern blot analysis with 32P-labeled CDNA probe which encodes 1.8 Kb IPSK gene was performed. These results suggest that IPSK are regulated at transcriptional level during rat tissue development.

• Journal of Nutrition and Health
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• v.35 no.1
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• pp.24-29
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• 2002

Present study investigates the protective effects of green tea against acute ethanol administration on lipid peroxidation and antioxidant system in various regions of rat brain ; cortex, cerebellum, striatum and hippofampus. The following parameters were examined : malondialdehyde(MDA) concentrations and activities of superoxide dismutase(SOD), catalase and glutathione peroxidase(GSH-Px). Male Sprague-Dawley rats of 9 month old were given control diets or those containing 1% green tea powder for 4 weeks, and at tole end of feeding each diet group was received acute ethanol(5g/kg body weight) or equicaloric sucrose solution administration. Results indicated that green tea powder significantly decreased malondialdehyde(MDA) levels in the striatum(81.85nmol/g tissue) and hippocampus(71.68nmol/g tissue), compared to control group(145.68nmol/g tissue in the striatum, 119.04nmol/g tissue in the hippocampus). Also, a significant decrease was observed in the striatum of green tea-ethanol treated group compared to control group. Green tea significantly blocked an ethanol-induced catalase activation in the hippocampus, which means an ethanol administration drew a significant increase only in control diet groups. In conclusion, these results suggest that moderate consumption of green tea leaves ctrl have protective effects against ethanol induced oxidative stress on various regions of rat brain, by significantly reducing MDA concentrations in the striatum and hippocampus and inhibiting ethanol induced catalase activation in the hippocampus.

• BMB Reports
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• v.29 no.2
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• pp.146-150
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• 1996

A 2.1 kb cDNA clone for rat transketolase was isolated from rat liver ${\lambda}gt11$ cDNA library and its sequence was determined. The predicted rat transketolase (655 amino acids with $M_r$ 71,186) is highly similar (92%) to that of the human enzyme except that it contains an extra 32 amino acids at its N-terminus. Although it is less similar (<27%) to transketolases from non-mammalian species, the functional motifs such as the catalytic sites and thiamine binding domain are well conserved in the rat enzyme. Southern blot analysis of genomic DNA verified that transketolase appears to be derived from a single gene. Immunoblot and Northern blot analyses suggested that hepatic transketolase was activated pretranslationally by a 2.1-fold while little change was observed in brain enzyme, indicating a tissue-specific pretranslational activation during postnatal development.