• Journal of the korean academy of Pediatric Dentistry
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• v.34 no.1
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• pp.53-61
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• 2007

In case of missing tooth caused by dental caries or periodontal disease, it can be restored by various methods, and there has been much interest in implant and tooth transplantation. The success of tooth transplantation is going to be attained through the knowledge of growth, development and calcification of tooth. Tooth transplantation has been experimented in vivo and in vitro. Many animals such as rats, mice, cats and dogs are used for tooth transplantation experiment in vivo. In most experiments, tooth was transplanted into the extraoral site, but rare into the intraoral site In this study, to observe the capacity of formation and mineralization of tooth germ, first molar of a matured white rat was extracted and the cap stage tooth germ of a 13.5 Embryonic day embryo rat was transplanted into the extracted socket. The rats were killed 6 months later and the radiographical and histological results are as followings. 1. Tooth germ transplanted for 2 and 6 months are developing calcified tooth material such as dentin, cementum, pulp tissue, and epithelium around enamel space in the maxilla was seen. 2. The epithelium around enamel space was located beneath the oral epithelium and contained connective tissue and periodontal ligament. 3. Tooth formation was progressed as transplantation period but the size of newly formed tooth was small and the shape of tooth was incomplete.

• Journal of radiological science and technology
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• v.26 no.3
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• pp.41-49
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• 2003

This study was undertaken to observe the histopathologic changes in submandibular glands of the white rats when exposed to megavoltage fractionated dose of CLINAC 2100 C-D 6 MV X-RAY irradiation and 42 female white rats, weighing approximately 100gm, were divided into control and 2 experimental groups. At sacrifice, submandibular glands were excised and examined microscopically and electromicroscopically. The results were as follows : 1. The acinar cells of submandibular gland showed damage varied with dose, 12 Gy resulted in very mild injury while 24 Gy caused extensive injury. 2. The acinar cells of sumandibular gland showed similar ultrastructual alterations, appeared as pleomorphic nucleus, decreased numbers and pleomorpgism of secretory granules, distention of rough endoplasmic reticulum, expansion and pallor appearance of mitochondria, and hypertrophy of Golgi complex. 3. A serous cells were the most sensitive components, displaying morphological alterations of radiation damage as early as 3 hours, followed by submandibular seromucinous cells and secretory tubular cells. 4. The mucous cells, as well as the whole ductal lining cells, displayed no significant alterations. 5. No evidence of microvascular injury through whole experimental groups indicated that microvascular impairment dose not contribute to early. salivary gland injury.

• Journal of the Korean Academy of Clinical Electrophysiology
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• v.1 no.1
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• pp.57-72
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• 2003

This study conducts electrical stimulation to male white rat of Spargue-Dawley which is 7 weeks, has the weight of 240 g and is seemingly healthy for one or two weeks by means of neuromuscular electrical stimulator in order to examine the effects of neuromuscular electrical stimulation on its gastrocnemius, measures change of weight of gastrocnemius, serum and enzyme activity and then obtains the following conclusions. There is little difference in AST and CPK of weight and serum of gastrocnemius after one or two weeks of conducting neuromuscular electrical stimulation in all experimental groups. On the one hand, as a result of histochemical observation, NMES I group showed hypertrophy of perimysium and increase of sectional diameter of muscle fiber compared to comparison group, but NMES II group showed a similar result to comparison group. When ultrasubstructure was observed under electron microscope, I-type muscle fiber of NMES I group showed well-arranged mitochondria and it was similar to comparison group. II-type muscle fiber showed a large quantity of glycogen granules within sarcoplasmatic and the extension of luminal of T-tubule. I-type muscle fiber of NMES II group had small mitochondria and showed the vacuolar degeneration of mitochondria and extended T-tubule. II-type muscle fiber showed the extension of agranule cytoplasma reticulum with T-tubule and the reduction of amount of glycogen granule within partial sarcoplasmatic.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1267-1272
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• 1998

In order to investigate the preventive and therapeutic of royal jelly on diabetes, the levels of blood glucose and serum lipids as well as the number of blood cells were determined in streptozotocin(STZ) diabetic rats. Rats were divided into seven groups. The RJ group was administered royal jelly and the STZ group was treated with streptozotocin to induce diabetes. To determine the preventive effect, diabetes was induced after administration of royal jelly for 2 weeks in group RS1/RS2. In group SR1/SR2 diabetic rats were administered royal jelly for 2 weeks to investigate the therapeutic effect. After 3 weeks, the body weight was reduced in STZ and SR1 groups and food intake was increased in the STZ, RS1 and SR1 groups. The blood glucose level was similar to the control group in the RJ, RS1 and RS2 groups and there was no effect in the other groups. The total lipid and triglyceride level were lower in the SR1 group as compared to STZ, and the total cholesterol level was higher in the STZ group. The index of atherogenesis was lower in the RJ and SR1 groups compared to the normal group. The number of red blood cells and hemoglobin was higher in the RJ and SR1 groups and the number of white blood cells was higher in the RJ and SR2 groups.

• Journal of Oriental Neuropsychiatry
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• v.12 no.2
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• pp.53-68
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• 2001

This study was performed to investigate the anti-depression effect of Guibiondamtang in rat model of depression. The rats in the experiment were stratified into 3 groups, ie, Guibiondamtang, saline, normal (non-stressed) groups. Chronic exposure to mild unpredictable stress such as white noise, flashing lights and restriction of food and water, causes the behavioral symptoms correspondent to depression. Consumption of 1% sucrose solution fell in rats exposed to CMS for 4 weeks. In the open field test , the exploratory activity ie. locomotion and centering decreased after CMS. We then evaluated the sucrose consumption and activity during 4 weeks of treatment with experimental drugs. The results were as follows: 1) There was no relation between sucrose intake and weight. 2) The Guibiondamtang(歸脾溫膽湯) group reinstated sucrose consumption within 5-6 weeks while having no influence on sucrose intake in normal group. 3) The Guibiondamtang(歸脾溫膽湯) group restored some exploratory activity in the open field test. 4) The Guibiondamtang-group had a-reduced potentiated startle response.

• Journal of the korean academy of Pediatric Dentistry
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• v.7 no.1
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• pp.75-83
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• 1980

Rickets is not the deposite of minerals in the skeletal tissue and the retardation of skeletal growth in growing in growing animals. This study was undertaken to investigate the histologic effects of experimental rickets on the dental structure of the albino rats, and to show the relationship between the histological effects and the pulpal disease which induced premature loss of the primary teeth. This study was based on material obtained from 40 white rats that were placed on a rachitogenic diet for a period 1 to 56 days after weaning (at 24 days). In addition, a study was made of 25 litter mates, 24 to 80 days, that were fed a normal diet. The following results were obtained: 1. Enamel formation and calcification showed no significant changes and no hypoplasia. 2. Dentin formation and calcification was retarded and disturbed. In the experimental group, predentin/calcified dentin was remarkablly increased. 3. Newly formed dentin showed interglobular texture (less homogenous calcification) and the predentin was significantly wider and thicker, and there was an irregular wave in the basal portion of the rat's incisors. 4. In cementum, Matrix formed at almost a normal rate but calcification was defective. So cementoid tissue was increasesd. 5. The formation of the alveolar bone was at almost a normal rate but calcification was retarded. The trabecular bone was filled with osteoid tissue and thicker than in normal groups.

• Journal of Korean Neurosurgical Society
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• v.29 no.7
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• pp.861-867
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• 2000

Purpose : Neuronal migration disorder(NMD) is a major underlying pathology of patients with intractable epilepsy. The role of NMD on seizure susceptibility or epileptogenecity, however, has not been documented. Methods : External irradiation of total amount of 250 cGY was performed to the fetal rats on days 16(E16) and 17(E17) of gestation. After delivery, the rats of 230-260g were decapitated for the histopathologic study. Epileptog-enecity of the NMD was studied by observing electroclinical events after intraperitoneal kainic acid(KA) injection in the control rats and NMD rats. Results : Histopathologic findings revealed focal and/or diffuse cortical dysplasia consisting of dyslamination of the cerebral cortex and appearance of the cytomegalic neurons, neuronal heterotopia in the periventricular white matter, dispersion of the pyramidal layer and the dentate gyrus of the hippocampus, and agenesis of the corpus callosum. Abnormal expression of neurofilaments protein(NF-M/H) was characteristically observed in the dysplastic neurons of the neocortex and hippocampus. Early ictal onset and prolonged ictal activity on EEG and clinical seizures were observed from the NMD rats unlike with the control rats. Conclusions : Exteranl irradiation on the fetal rats produced NMD. And the rats with NMD were highly susceptible to kainic acid provoked seizures. This animal model would be useful to study the pathophysiology of clinically relevant NMDs.

• Advances in environmental research
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• v.1 no.2
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• pp.109-123
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• 2012

Our study investigated the effects of Solanum macrocarpon (African eggplant) on haematological and biochemical parameters of male albino rats exposed to urban air pollution ($O_3$, $PM_{10}$, CO, $SO_2$, $NO_2$ and VOC). Male albino Wistar rats were exposed for 63 days either to urban air pollution without treatment (A); oral supplementation with Solanum macrocarpon given at 36 and 75 mg/kg body weight (BW), representing C and D respectively and exposed to air pollution; oral supplementation with Solanum macrocarpon given at 75 mg/kg BW after exposure to air pollution (B); or kept in animal house without exposure to air pollution (E). Animals exposed to air pollution showed significant alterations in haematological and biochemical parameters signaling that the blood and organs were badly injured. There were significant elevations in white blood cells (WBC) and its indices, reduction in red blood cells (RBC) and significant depletions of non-enzymic antioxidants, total protein and increase in lipid peroxidation values. Solanum macrocarpon supplementation in the feed of animals halted significantly the deleterious effects of air pollution, with co-administration during exposure given better results.

• Environmental Mutagens and Carcinogens
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• v.16 no.1
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• pp.35-42
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• 1996

Aragonite is one of polymorphs of calcium carbonate of which main form is calcite. We found that white precipitate is formed in much amount by boiling underwater of Inchon, Korea and confirmed that it is aragonite. This study is to evaluate the dimensional characteristics, solubility, acid resistance of aragonite and the cytotoxicity, cell division disturbance and cell transforming ability of it on BALB/3T3 cells. The results are as follows: Lengths of the aragonite were reduced to the 72.7% and 22.7% respectively after 5 months and 7 months of intrapleurai injection to the Sprague-Dawley rat. Strong acid such as 1M HCl dissolved the aragonite instantly but weaker acid pH 2.0 or more could not dissolved aragonite easily. The result of cell growth inhibition showed that cell numbers were decreased as log-doses of treatment of the aragonite were increased 24 hours, 48 hours, and 72 hours later. Cell plating efficiency after the aragonite treatment also showed dose-dependent decrease. Multinuclear giant cell formation was increased in the aragonite treated cells until ID$_{50}$ and after the dose the multinucleate cells were decreased, but remained much higher than negative control cells. Morphological transformation assay showed that the aragonite did not induce transformation in all treated doses.

• Archives of Craniofacial Surgery
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• v.16 no.2
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• pp.73-79
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• 2015

Background: Alprostadil and sildenafil are known vasodilators used independently to improve flap survival in animal models. In this study, we investigate whether these agents act synergistically to decrease flap necrosis in rat models. Methods: After acclimation period, 4 groups of 10 male white rats were given a modified McFarlane skin flap. The postoperative treatment included saline control (Group A), sildenafil citrate-only (Group B), alprostadil-only (Group C), and both sildenafil and alprostadil (Group D). The flaps were observed on postoperative days 1, 3, 5 and 7. The animals were euthenized on postoperative day 7, and the flaps were evaluated for inflammation and neovascularization. Results: At each observation, the mean necrotic index was significantly lower for all three treatment groups (Groups A, B, C) and was the lowest for the combined treatment group. On histologic evaluations, combined treatment was associated with decreased inflammation and increased capillary vessel formation, when compared with control group. Conclusion: Both sildenafil-only and alprostadil treatments were independently associated with increased flap survival rate. Sildenafil citrate and alprostadil had a synergistic effect in increasing flap survival rate.