• Maxillofacial Plastic and Reconstructive Surgery
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• v.32 no.4
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• pp.293-298
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• 2010

Purpose: The objective of the present study was to determine the capability of electrospun silk fibroin as a biomaterial template for bone formation when mixed with nano-hydoxyapatite in vivo. Materials and Methods: Ten New Zealand white rabbits were used for this study and bilateral round shaped defects were formed in the parietal bone (diameter: 8.0 mm). The electrospun silk fibroin was coated by nano-hydroxyapatite and grafted into the right parietal bone (experimental group). The left side (control group) did not receive a graft. The animals were sacrificed at 6 weeks and 12 weeks, humanly. The microcomputerized tomogram (${\mu}CT$) was taken for each specimen. Subsequently, they were undergone decalcification and stained for the histological analysis. Results: The average value of all measured variables was higher in the experimental group than in the control at 6 weeks after the operation. BMC in the experimental group at 6 weeks after operation was $48.94{\pm}19.25$ and that in the control was $26.17{\pm}16.40$ (P = 0.027). BMD in the experimental group at 6 weeks after operation was $324.59{\pm}165.24$ and that in the control was $173.03{\pm}120.30$ (P = 0.044). TMC in the experimental group at 6 weeks after operation was $19.50{\pm}6.00$ and that in the control was $10.52{\pm}6.20$ (P = 0.011). TMD in the experimental group at 6 weeks after operation was $508.88{\pm}297.57$ and that in the control was $273.54{\pm}175.91$ (P = 0.06). Gross image of both groups showed higher calcification area at 12 weeks than them in 6 weeks. The average value of ${\mu}CT$ analysis was higher at 12 weeks than that in 6 weeks in both groups. BMC in the experimental group at 12 weeks after operation was $51.21{\pm}8.81$ and that in the control was $33.47{\pm}11.13$ (P = 0.010). BMD in the experimental group at 12 weeks after operation was $323.39{\pm}21.54$ and that in the control was $197.75{\pm}76.23$ (P = 0.012). TMC in the experimental group at 12 weeks after operation was $21.44{\pm}5.30$ and that in the control was $13.31{\pm}4.17$ (P = 0.008). TMD in the experimental group at 12 weeks after operation was $524.47{\pm}19.37$ and that in the control was $299.60{\pm}136.20$ (P = 0.016). Conclusion: The rabbit calvarial defect could be successfully repaired by electrospun silk nano-fiber combined with nano-hydroxyapatite.

• The korean journal of orthodontics
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• v.32 no.2 s.91
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• pp.107-115
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• 2002

The aim of this study was to investigate experimentally the mechanical and histological effect of drilling process on the stability of micro-implant used for the orthodontic anchorage. For this purpose, 32 micro-implants(Osas$^{(R)}$, Epoch medical, ${\phi}$1.6 mm) were inserted into maxilla, mandible and palate in two beagle dogs. 16 micro-implants(8 per dog) were inserted after drilling with pilot drilling bur (drill method group). 16 micro-implants(8 per dog) were inserted without drilling (drill-free method group). After 1 week, micro-implants were loaded by means of Ni-Ti coil spring (Ni-Ti springs-extension$^{(R)}$, Ormco) with 200-300 gm force. Following 12 weeks, the micro-implants and the surrounding bone were removed. Before sacrifice, the mobilities were tested with Periotest$^{(R)}$(Siemens). Undecalcified serial sections with the long axis were made and the histologic evaluations were done. The results of this study were as follow ; 1. The osseointegration was found in both of drill-free method group and drill method group 2. Two of drill method group and one of drill-free method group in 32 micro-implants were lost after loading. 3. The mobilities of drill-free method group were less than drill method group 4. The bone contact on surface of micro-implants in drill-free method group was more than drill method group but there was no significant difference between groups. 5. The bone density in threads of micro-implants in drill-free method group was more than drill method group and there was significant difference between groups. These results suggest that drill-free method in insertion of micro-implants is superior to drill method on the stabilities, bone remodeling and osseointegrations under early loading.

• Clinical and Experimental Pediatrics
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• v.51 no.5
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• pp.492-499
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• 2008

Purpose : Helicobacter pylori infection is one of the most common gastrointestinal infections worldwide; it almost invariably causes chronic gastritis. Pediatric studies may provide important insights into the mucosal immune response of H. pylori-infection, as children are not submitted to environmental factors such as alcohol, tobacco and anti-inflammatory medication. The aim of the present study was to investigate the mucosal immune response against H. pylori in clinically well-defined groups: H. pylori-positive (divided into peptic ulcer disease and gastritis) and H. pylori-negative control. Methods : Antral biopsies were obtained from 45 children undergoing an upper GI endoscopy for dyspeptic symptoms. T cells (CD3+, CD4+, CD8+) and B cells (CD20+) were analyzed by quantitative immunohistochemistry. The correlation of lymphocyte subsets of gastric mucosa with histology was evaluated. Results : T cells (CD3+, CD4+, CD8+) and B cells (CD20+) were significantly increased in the lamina propria of H. pylori-positive group (P<0.01). CD8+ T cells were significantly increased in the lamina propria of the H. pylori-positive peptic ulcer disease (P<0.01). Within the epithelium, only CD4+ T cells were significantly increased in the H. pylori-positive group (P<0.01). Gastric histological parameters had a closer correlation with lymphocytes in the lamina propria than intraepithelial lymphocytes. Conclusion : This study suggests that both T cells and B cells in the lamina propria play important roles in the local immune response of H. pylori-infected children. Furthermore, it remains to be elucidated whether CD8+ T cells in the lamina propria may contribute to peptic ulcer formation in H. pylori-infected children.

• Tuberculosis and Respiratory Diseases
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• v.62 no.6
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• pp.523-530
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• 2007

Background: A ThinPrep$^{(R)}$ Processor was developed to overcome the limitations of conventional cytology and is widely used to diagnose various cancers. This study compared the diagnostic efficacy of conventional cytology for lung cancer with that of the ThinPrep$^{(R)}$ cytology using the bronchial washing fluid. Methods: The bronchial washing fluid of 790 patients from Jan. 2002 to Dec. 2006, who were suspected of gaving a lung malignancy, was evaluated. Both ThinPrep$^{(R)}$ and conventional cytology were performed for all specimens. Result: Four hundred forty-six men and 344 women were enrolled in this study, and 197 of them were diagnosed with cancer from either a bronchoscopic biopsy or a percutaneous needle aspiration biopsy. ThinPrep$^{(R)}$ cytology showed a sensitivity, specificity, positive predictive value, negative predictive value and false negative error rate of 71.1%, 98.0%, 92.1%, 91.1%, 8.9%, respectively. The conventional cytology showed sensitivity, specificity, positive predictive value, nagative predictive value and false negative error rate of 57.9%, 98.0%, 90.5%, 87.5%, 12.5%, respectively. For central lesions, the sensitivity of conventional cytology and ThinPrep$^{(R)}$ were 70.1% and 82.8%, respectively. Conclusion: ThinPrep$^{(R)}$ cytology showed a higher sensitivity and lower false negative error rate than conventional cytology. This result was unaffected by the histological classification of lung cancer. Therefore, ThinPrep$^{(R)}$ cytology appears to be a useful method for increasing the detection rate of lung cancer in bronchial washing cytology test.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.9
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• pp.1344-1349
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• 2005

The aim of this study was to evaluate the effects of Welsh onion administration on $CCl_4$-induced hepatic injury in rats. The increasing rate of the body and organ weight was not significantly different by the ad-ministration of the Welsh onion. Welsh onion (2, 4, $10\%$ w/w) was given for 4 weeks with the injections of $CCl_4$. Total serum lipid was significantly decreased in all treatment groups compared to $CCl_4$ only treatment group (p<0.05). The Welsh onion from winter season was more protective effect by lowering the serum levels of transminase (SGOT and SGPT) compared with others, the levels of transminase - phosphatase (ALP) in serum. The Welsh onion from winter at a dose of $4\%,\;10\%$ (w/w) showed significantly hepatoprotective activity which was comparable to that $CCl_4$-induced hepatic damage. Histological evaluation showed that Welsh onion partially prevented $CCl_4$-induced inflammation, necrosis and vacuolation. Pretreatment of Welsh onion reduced extent of the necrosis found 24 hr after the intraperitoneal administration of $CCl_4$. The present study shows the liver protective action of the Welsh onion against experimentally induced liver damage in rats. This suggests that the Welsh onion may be used as an effective hepatoprotective agent.

• The Korean Journal of Pharmacology
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• v.32 no.1
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• pp.113-123
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• 1996

It has been well known that polyamines ensure the stability of chromatin structure and the fidelity of DNA transcription. This study was carried out to evaluate the effect of polyamines on the apoptosis of mouse thymocytes induced by dexamethasone and polyamine synthesis inhibitors. 1) In the histological death findings of thymocytes double-stained with acridine orange and ethidium bromide, the apoptotic and the necrotic fractions (AF; NF) in the control group were $9.4{\pm}4.2%$ and $4.5{\pm}5.3%$, respectively. Dexamethasone $(3\;{\times}\;10^{-8}\;M:\;DX)$ in creased AF upto $52.0{\pm}8.1%$ and did not change NF, but A23187 $(5\;{\times}\;10^{-7}\;M:\;A2)$ increased AF and NF upto $45.0{\pm}8.9%$ and $20.5{\pm}10.6%$, respectively. 2) The thymocyte viability was significantly reduced by DX, DHEA $(1\;{\times}\;10^{-4}\;M)$, A2, DFMO $(1\;{\times}\;10^{-4}\;M)$, and $MGBG\;(1\;{\times}\;10^{-4}\;M)$, respectively. It was, however, little affected by $aminoguanidine\;(1\;{\times}\;10^{-4}\;M:\;AG)$, $putrescine\;(1\;{\times}\;10^{-5}\;M:\;PT)$, $spermidine\;(1\;{\times}\;10^{-5}\;M:\;SD)$, and $spermine\;(1\;{\times}\;10^{-5}\;M:\;SM)$. 3) The genomic DNA of mouse thymocyte was markedly fragmented by DX and A2, respectively, and to a lesser extent, by DHEA, but was little affected by MGBG, DFMO, AG, and each of polyamines. 4) The DX induced reduction of thymocyte viability was moderately attenuated by DHEA, but little affected by DFMO, MGBC, and AG. However, SM significantly attenuated the viability reduction induced by A2 as well as DX. 5) The thymocyte viability reduction by MGBG and DFMO was significantly attenuated by only SM among three polyamines applied in this study. 6) The thymocyte viability redution by combined treatments of DX with DFMO and MGBG, respectively, was significantly attenuated by SM, and moderately by PT. But the viability reduction by combined treatment of DX with AG or DHEA was not affected by polyamines. These results suggest that polyamines, particularly spermine, might play the inhibitory role in thymocyte apoptosis and the inhibitory effect can be ascribed in part to the increase of polyamine uptake by thymocytes pretreated with DFMO and MGBG.

• Korean Journal of Food Science and Technology
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• v.39 no.4
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• pp.470-475
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• 2007

Oplopanax elatus (O. elatus) is a tall deciduous shrub that has traditionally been used for σ eating a variety of ailments such as diabetes, coughling, rheumatism, gastro-intestinal disorders, and wounds. In order to examine the safety of the ethanol extracts of O. elatus, we performed a 14-day repeated-dose toxicity study with Sprague-Dawley rats. The rats were treated with daily doses of the D. elatus ethanol extracts by gavage at 0, 500, 1000, and 2000 mg/kg/day for 14 consecutive days. We recorded clinical signs of toxicity, body weight, hematology, organ weights, gross and histological changes in target organs, and clinical chemistry analysis data for all rats. There were no significant changes in body and organ weights during the experimental period. The hematological analysis and clinical blood chemistry data revealed no toxic effects from the O. elatus ethanol extracts. Pathologically, neither gross abnormalities nor histopathological changes were observed between the control and treated rats of both sexes. Collectively, these data suggest that the ethanol extracts of O. elatus have a high margin of safety.

• Korean Journal of Animal Reproduction
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• v.21 no.3
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• pp.255-264
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• 1997

The purpose of this study was attempted to investigate the number changes of the growing and mature follicles in ovary following repeats of pregnant mare serum gonadotropin(PMSG) treatments for superovulation in nulliparous rats. Thirty two rats(Sprague-Dawely, about 200~250 gm) were randomized into 4 groups. Control group rats were sacrified at estrus phase confirmed by vaginal smear. PMSG-treated group 1 rats, PMSG-treated group 2 rats and PMSG-treated group 3 rats were sacrified at 48 hrs after injection once with PMSG 25 IU, after 2 repeated injection by a week interval, and 3 repeated injection, respectively. The uteri and ovaries of rats were removed and weighed and then were observed grossly and serial sections of all ovaries and some sections of uteri by paraffin embedding were stained with H-E. Number of ovarian follicles about 3 grades of small, middle and large follicles from seondary and follicles were investigated by LM photographies of ovary preparations. The criteria of the small, middle, and large follicles were based as small follicle with preantral follicles with 2~4 layers of granulosa cells surrounding the oocyte, as secondary follicles with more than 5 layers of granulosa cells and early signs of antral cavity or with small clefts on either side of the oocytes, and as tirtiary follicles with a single medium sized antral cavity or large well-formed antral cavity, respectively. In gross findings, the wall of the uteri in control group were thin, and those in 3 PMS-treated group were markedly thickened and some uterine lumen of those filled with fluid. In histological findings, the walls of the uteri from 3 PMSG-treated groups were hypertrophied and their blood and lymph vessels were dilated than those of control group. The ovaries fo 3 PMSG-treated groups were more increased in size and the cortexes were more developed and increased in width but there are no difference of development and changes in 3 PMSG-treated groups. The weight of the uteri and ovaries per rat in PMSG -treated group 1, 2 and 3 were a, pp.ared to be significantly increased 171.4$\pm$47.6%, 162.3$\pm$43.9%, 206.9$\pm$30.4%, respectively than those of control groups. The mean number of follicle per ovary in control group were a, pp.ared to be 17.1$\pm$3.5, 46.2$\pm$14.5, and 74.3$\pm$22.7 at large, middle and small follicles, respectively and total number of these 3 grade follicles per ovary were a, pp.ared to be 137.7$\pm$31.7. The mean number of follicle per ovary in PMSG-treated group 1 were a, pp.ared to be 25.6$\pm$7.3, 78.1$\pm$29.9, and 83.2$\pm$34.0, at large, middle and small follicles, respectively and total number of these 3 grade follicles were a, pp.ared to be 187.5$\pm$58.8. The mean number of follicle per ovary in PMS-treated group 2 were a, pp.ared to be 21.9$\pm$5.2, 67.8$\pm$16.8, and 68.0$\pm$14.9 at large, middle and small follicles, respectively and total number of these 3 grade follicles were a, pp.ared to be 157.7$\pm$26.2. The mean number of follicle per ovary in PMS-treated group 3 were a, pp.ared to be 21.7$\pm$4.8, 61.5$\pm$17.0, and 59.7$\pm$16.2 at large, middle and small follicles, respectively and total number of these 3 grade follicles were a, pp.ared to be 143.5$\pm$29.6. The number of follicles in PMSG-treated group 1 a, pp.ared to be more number than other 2 PMSG-treated gruops and tended to be decreased by frequency of PMSG-treatment.

• Restorative Dentistry and Endodontics
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• v.32 no.2
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• pp.95-101
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• 2007

This study was performed to verify the possibility of MTA and calcium sulfate as a pulp capping agent through comparing the dental pulp response in dogs after capping with MTA, calcium sulfate, and calcium hydroxide. 24 teeth of 2 dogs, 8 month old, were used in this study. Under general anesthesia, cervical cavities were prepared and pulp was exposed with sterilized #2 round bur in a high speed handpiece. MTA calcium hydroxide, and calcium sulfate were applied on the exposed pulp. Then the coronal openin,fs were sealed with IRM and light-cured composite. Two months after treatment, the animals were sacrificed. The extracted teeth were fixed in 10% neutral-buffered formalin solution and were decalcified in formic acid-sodium citrate. They were prepared for histological examination in the usual manner. The sections were stained with haematoxylin and eosin. In MTA group, a hard tissue bridges formation and newly formed odontoblasts layer was observed. There was no sign of pulp inflammatory reaction in pulp tissue. In calcium hydroxide group, there was no odontoblast layer below the dentin bridge. In pulpal tissue, chronic inflammatory reaction with variable intensity and extension occurred in all samples. In calcium sulfate group, newly formed odontoblast layer was observed below the bridge. Mild chronic inflammation with a few neutrophil infiltrations was observed on pulp tissue. These results suggest that MTA is more biocompatible on pulp tissue than calcium hydroxide or calcium sulfate.

• Journal of Dental Rehabilitation and Applied Science
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• v.25 no.2
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• pp.125-137
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• 2009

There are many reports that these implant surface treatments may affect to cellular reaction in the surface of implant. This study was done by installing the 8 type implant with the variable surface treatment, used or developed, in the mandible of the mature dog to evaluate how the method of surface treatment of the implant can affect to the bone healing by analyzing histologically and histomorphometrically and find out bone healing appearance periodically after installing implant. By using the 8 type implants which have the different surface treatment, 72 implants were installed on the mandible of 9 mature dogs, and 3 dogs were sacrificed on every 2, 4, 8 weeks. After making bone fragment by cutting and managing, we analyzed histologically, then compared with BIC(Bone to implant contact) for the histomorphometrical analysis. In the result of histological analysis, there was large amount of bone formation in good state on the adjacent area of implant in the 2 weeks testing group. At 4 weeks, although there was general bone formation, the new bone was separated with the basal bone. At 8 weeks, the new bone became matured and connected tightly to the basal bone. There was no difference in the each surface of 8 implants. In the result of histomorphometrical analysis, 2 weeks group had considerably lower value than 4 and 8 weeks group, and there was no difference between 4 and 8 weeks group. There was no difference in the each surface treatment of implants.