• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.587-602
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• 1995

The purpose of this study was to compare the effects of citric acid and tetracycline HCI application to the root surfaces of periodontally diseased teeth on the proliferation and spreading of human periodontal ligament cells. The roots were prepared so that the comparison could be made among root planed, citric acid treated and tetracycline HCI treated surfaces. In the cell proliferation experiment, human periodontal ligament cells at a concentration of $1{\times}10^5$ cells/ml were seeded in each culture well with specimens and incubated for 6 hours. Then, the specimens were transferred to a fresh culture well and incubated for 24, 48, 72 hours respectively. The cell counting was done after trypsinization. In the cell spreading experiment, $1{\times}10^4$ cells/ml were seeded in each culture well and incubated for 30min, 6 hours and 24 hours at 37.5$^{\circ}C$ in a $CO_2$ incubator. Then, all specimens were fixed with phosphate buffered glutaraldehydes, postfixed with phosphate buffered osmium tetraoxide, stained with phosphate buffered tannic acid, dehydrated in ethanol, dried at a critical point, coated with gold and examined under a scanning electron microscope. The results were as follows:In the cell proliferation experiments, the number of attached cells increased more in the tetracycline treated group than in the other groups. In the initial attachment, the appearance of the tetracycline treated the groups was slightly more spread out than in the other groups. After 6 hours of incubation, it was observed in most of the cells that cell morphologic alteration went from ovoid shapes sto spindle shapes. After 24 hours of incubation, the cells of all groups had a fusiform appearance and were connected to each other by numerous cytoplasmic processes. The tetracycline and citric acid treated groups had a similar spreading appearance of periodontal ligament cells, but the tetracycline treated group was more effective in the cell proliferation than the citric acid group.

• Journal of Periodontal and Implant Science
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• v.25 no.3
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• pp.741-755
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• 1995

Currently titanium is the material of choice for implants because of its biological acceptance. This high degree of biocompatibility is thought to result, in part, from the protective and stable oxide layer that presumably aids in the bonding of the extracellular matrix at the implant-tissue interface. Endosseous dental implants are interfaced with bone, connective tissue, and epithelium when implanted into the jaw bone. The soft tissue interface including connective tissue and epithelium is one of the most critical factors in the determination of implant maintenance and prognosis. For maintenance of failing or failed implants, it is essential to treat the implant fixture surface to remove bacterial endotoxins and make a surface tolerated by surrounding soft and hard tissues. In this study, the effect of mechanical treatment on titanium plasma sprayed implant on adhesiveness and proliferation of human gingival fibroblasts and changed surface characteristics were studied. titanium plasma sprayed discs manufactured by Friedrichsfeld company were treated with loaw speed stone bur, a rubber point and a jetpolisher. Its surface components were analyzed with Energy dispersive X-ray spectroscopy to evaluate whether the surface characteristics were altered or not. To observe the spreading pattern of the human gingival fibroblasts which attached to the all specimens author used the scanning electron microscope. The results were as follows : Pure titanium and plasma sprayed titanium, stone polished titanium showed titanium peak and small amout of aluminum, so there was no alteration on surface characteristics. Under the scanning electron microscopic examination in the initial attachment of human gingival fibroblast, there was a slight enhancement in pure titanium, stone polished titanium than plasma sprayed titanium. After 6 hours, the pure titanium and stone polished titanium showed human gingival fibroblasts were elongated and connected with numerous processes. Human gingival fibroblasts were more intimately attached on the pure titanium discs than on the other discs. The human gingival fibroblasts attached on the plasma sprayed titanium by thin and elongated processes. After 24 hours, the human gingival fibroblasts connected with each other via numerous processes and compeletly covered the pure titanium and stone polshed titanium discs. Human gingival fibroblasts had multiple point contacts with more long and thin lamellopodia and showed a little bare surface on plasma sprayed titanium discs.

• Journal of Gastric Cancer
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• v.7 no.4
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• pp.185-192
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• 2007

Purpose: RUNX3, a novel tumor suppressor, is frequently inactivated in gastric cancer. In the present study, we examined the pattern of RUNX3 expression in gastric cancer cells from gastric cancer specimens and the impact of its alteration on clinical outcome. Materials and Methods: A total of 124 samples of both gastric cancer and normal tissue were obtained from 124 patients who underwent curative gastrectomy at the Seoul Medical Center from January 2001 to December 2005. RUNX3 expression was determined by immunohistochemical staining, and the results were analyzed. Statistical analysis wabased on clinicopathological findings and differences in survival rates. Results: The mean age of the patients was 61 years, and the male:female ratio was 1.9:1. The expression rate of RUNX3 was 59.7% (74/124). The expression rate was higher in differentiated gastric cancers (nucleus: 9.1%, cytoplasm: 57.6%) than in the undifferentiated types (nucleus: 5.2%, cytoplasm: 46.6%) (P=0.133). The 5-year survival rates according to RUNX3 expression determined from cancer tissue were 88.9% for the nucleus $\pm$ cytoplasm(+) group of patients, 76.1% for the cytoplasm only (+) group of patients, and 65.3% for the RUNX3 negative expression group of patients (P=0.626). Only UICC TNM staging showed statistical significance related to the survival rate, as determined by multivariate analysis. Conclusion: The RUNX3 expression rate was higher in differentiated gastric cancer than in the undifferentiated types without significance. Although RUNX3 expression predicted better survival, based on multivariate analysis, the finding was not statistically significant. More cases should be further evaluated.

• Progress in Medical Physics
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• v.19 no.2
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• pp.95-101
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• 2008

In this study, we observed the alteration of choline signal intensity in hippocampus region of the depressive rat model induced by forced swimming test (FST). The purpose of this study was to evaluate the antidepressant efficacy in the depressive animal model using MR spectroscopy. Fourteen experimentally naive male Sprague-Dawley rats weighting $160{\sim}180\;g$ were used as subjects. Drug injection group was exposed to the FST except for control group. The drugs were administered subcutaneously (SC) in a volume equivalent to 2ml/kg. And three injections were administered 23, 5, and 1h before beginning the given test. 1H MR spectra were obtained with use of a point resolved spectroscopy (PRESS) localization sequence performed according to the following parameters: repetition time, 2500 ms; echo time, 144 ms; 512 average; 2048 complex data points; voxel dimensions, $1.5{\times}2.5{\times}2.5\;mm^3$ ; acquisition time, 25min. There were no differences in NAA/Cr and Cho/Cr ratio between the right and the left hippocampus both normal control rats and antidepressant-injected rats. Also, no differences were observed in NAA/Cr and Cho/Cr ratio between the normal control rats and the antidepressant-injected rats both the right and the left hippocampus. In this study, we found the recovery of choline signals in the depressive animal model similar to normal control groups as injecting desipramine-HCl which was antidepressant causing anti-immobility effects. Thus, we demonstrated that MR spectroscopy was able to aid in evaluating the antidepressant effect of desipramine-HCl.

• Journal of Plant Biotechnology
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• v.38 no.4
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• pp.285-292
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• 2011

In plants, heteroblasty reflects the morphological adaptation during leaf development according to the external environmental condition and affects the final shape and size of organ. Among parameters displaying heteroblasty, leaf index is an important and typical one to represent the shape and size of simple leaves. Leaf index factor is eventually determined by cell proliferation and cell expansion in leaf blades. Although several regulators and their mechanisms controlling the cell division and cell expansion in leaf development have been studied, it does not fully provide a blueprint of organ formation and morphogenesis during environmental changes. To investigate genes and their mechanisms controlling leaf index during leaf development, we carried out molecular-genetic and physiological experiments using an Arabidopsis mutant. In this study, we identified macrophylla (mac) which had enlarged leaves. In detail, the mac mutant showed alteration in leaf index and cell expansion in direction of width and length, resulting in not only modification of leaf shape but also disruption of heteroblasty. Molecular-genetic studies indicated that mac mutant had point mutation in ROTUDIFOLIA3 (ROT3) gene involved in brassinosteroid biosynthesis and was an allele of rot3-1 mutant. We named it mac/rot3-5 mutant. The expression of ROT3 gene was controlled by negative feedback inhibition by the treatment of brassinosteroid hormone, suggesting that ROT3 gene was involved in brassinosteroid biosynthesis. In dark condition, in addition, the expression of ROT3 gene was up-regulated and mac/rot3-5 mutant showed lower response, compare to wild type in petiole elongation. This study suggests that ROT3 gene has an important role in control of leaf index during leaf expansion process for proper environmental adaptation, such as shade avoidance syndrome, via the control of brassinosteroid biosynthesis.

• Journal of Life Science
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• v.20 no.2
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• pp.281-291
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• 2010

We investigated the antioxidant effects of hederagenin 3-O-b-D-glucopyranosyl($1{\rightarrow}3$)-a-L-rhamnopyranosyl($1{\rightarrow}2$)-a-L-arabinopyranoside (HDL) isolated from root bark of Ulmus davidiana on the activity of enzymes related to reactive oxygen species (ROS) in human osteosarcoma U2OS cells. Cobalt chloride ($CoCl_2$), a transition metal, was used as an inducer of oxidative stress, generating hydrogen peroxide ($H_2O_2$) via increasing xanthine oxidase (XO) activity. The increased levels of $H_2O_2$, XO, ferritin, and ferritin iron by $CoCl_2$ were diminished effectively by co-treatment with HDL in U2OS cells. Furthermore, decreased levels of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) by $CoCl_2$ were highly increased by co-treatment with HDL in U2OS cells; however, the levels of glutathione peroxidase (GPx) did not change. The increased contents of TBARS related to lipid peroxidation were significantly reduced by HDL in U2OS cells. The concentration of GSH changed in a pattern that went against regulated TBARS by $CoCl_2$ and HDL. We examined the expression of p53, $p21^{CIP1/WAF1}$, and $p27^{KIP1}$ proteins related to oxidative stress and cell cycle regulation. As a result, the expression of $p27^{KIP1}$ modulated by $CoCl_2$ was not changed by HDL. However, the expression of p53 and $p21^{CIP1/WAF}$ increased by $CoCl_2$ was reduced by HDL in U2OS cells. Together with alteration of p53 and $p21^{CIP1/WAF1}$ proteins, the accumulated cells at G1 phase by $CoCl_2$ was decreased by HDL in U2OS cells. Our data suggests that HDL inhibits $CoCl_2$-generated ROS in U2OS cells, providing potentially new antioxidant compounds that are isolated from natural products.

• Pediatric Infection and Vaccine
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• v.7 no.1
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• pp.94-107
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• 2000

Purpose : The purpose of this study is to know the clinical manifestations and the severity of adenoviral lower respiratory tract infections(LRTI) in Korean children. Methods : Adenoviral respiratory infection was diagnosed by viral culture in HEp-2 cell and indirect immunofluorescent technique with nasal aspirates. Isolated adenoviruses were typed by neutralization test. Retrospective chart review was done in patients with adenoviruses were typed by neutralization test. Retrospective chart review was done in patients with adenoviral lower respiratory tract infection, who were brought to Seoul National University Children's Hospital from November 1990 through February 1998. Results : Adenovirus was isolated in 87 cases. Of 84 cases serotyped, type 1 was recovered in 3 cases, type 2 in 13 cases, type 3 in 13, type 4 and 5 in 4 cases each other, type 6 in 1 cases, type 7 in 36 cases, type 11 in 1 case and the other types in 9 cases. Adenoviral lower respiratory infection occurred sporadically throughout the year but from November 1995 through February 1998, an outbreak of adenovirus type 7 lower respiratory infection was observed in number upto 36 case. The incidence of adenoviral infection peaked in young children between 6 months and 5 years of age and the mean age was 1 year 11 months old. There were 10 cases of mixed infection with another pathogen. Clinical diagnosis were pneumonia(88%), acute broncholitis(5.4%), acute tracheobronchitis(5.4%), croup(1.3%). The clinical features of adenoviral lower respiratory infection were severe especially in type 3 and 7 infections in aspect of fever duration, ventilator care. Extrapulmonary manifestations were gastrointestinal symptoms in 23 cases(31%), hepatomegaly in 36 cases(53%), seizure and mental alteration in 13 cases(20.3%). In chest radiographic findings, parahilar and peribronchial infiltration were in 49 cases(67%), hyperaeration in 21 cases(29%), atelectasis in 14 cases(19%), consolidation in 39 cases(53%) and bilateral pneumonic infiltration in 28 cases(38%). Among thirty six adenovirus type 7 LRTI, 15 patients(41.6%) had pleural effusion and 3 patients had chest tube insertion. Number of fetal cases related to adenovirus were 9 cases(12%) and fetal cases due to ventilatory failure were 7(11%). Conclusion : During 7 year period of studying adenoviral lower respiratory infection, we identified the serotypes of adenovirus. Among the serotypes, adenovirus type 7 were epidemically isolated. Adenovirus were isolated in severe lower respiratory infection of young children aged between 6 months and 5 years and related to death of the patients, especially when the patients had underlyng diseases or were infected by adenovirus type 7.

• Journal of Life Science
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• v.21 no.8
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• pp.1149-1155
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• 2011

Myostatin (MSTN) belongs to the transforming growth factor-${\beta}$ superfamily or growth and differentiation factor 8 (GDF-8), and functions as a negative regulator of skeletal muscle development and growth. Previous studies in mammals have suggested that myostatin knock-out increased muscle mass and decreased fat content compared to those of the wide type. Recently, several studies on myostatin have beenconducted on the block myostatin signal pathway with myostatin antagonists and the MSTN regulation with RNAi to control myostatin function. This study was performed to analyze growth and muscle alteration of Oncorhychus masou by treatment with recombinant myostatin prodomains derived from fish. We designed myostatin prodomains derived from P. olivaceus (pMALc2x-poMSTNpro) and S. schlegeli (pMALc2x-sMSTNpro) in a pMALc2x expression vector, and then purified the recombinant proteins using affinity chromatography. The purified recombinant proteins were treated in O. masou through an immersion method. Recombinant protein treated groups did not show a significant difference in weight, protein, or lipid composition compared to the control. However, there was a difference in the average number and area for histological analyses in the muscle fiber. At twelve and twenty-two weeks from the initial treatment, there were differences in averagefiber number and area between the 0.05 mg/l treated-group and the control, but the numbers were similar to those of the control during the same time period. At twelve weeks, however, 0.2 mg/l treated-group had an increase in average fiber number and decrease in average fiber area compared to the control. At twenty-two weeks, the pMALc2x-sMSTNpro 0.2 mg/l treated-group was induced and showed a decrease in average fiber number and increase in average fiber area. The results between twelve and twenty-two weeks showed that the fiber numbers had decreased, whereas average fiberarea had increased due to sMSTNpro. It is understood that the sMSTNpro induced only hyperplasia at twelve weeks, after which it induced hypertrophy. Recombinant myostatin prodomains derived from fish may induce hyperplasia and hypertrophy in O. masou depending upon the time that has elapsed.

• Journal of Life Science
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• v.21 no.8
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• pp.1134-1141
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• 2011

Transmembrane protein 21 (TMP21) is a member of the p24 cargo protein family and has been shown to modulate ${\alpha}$-secretase-mediated A${\beta}$ production which was specifically observed in the brains of subjects with Alzheimer's disease (AD). In order to investigate whether TMP21 could affect nerve growth factor (NGF) receptor signaling pathway, the alteration of NGF receptors and their downstream proteins were detected in TMP21 over-expressed cells. CMV/hTMP21 vector used in this study was successfully expressed into TMP21 proteins in B35 cells after lipofectamin transfection. Expressed TMP21 proteins induced the down-regulation of ${\gamma}$-secretase complex components including Presenlin-1 (PS-1), PS-2, Nicastrin (NST), Pen-2 and APH-1. Also, the expression level of NGF receptor $p75^{NTR}$ and RhoA were significantly higher in CMV/hTMP21 transfectants than vehicle transfectants, while their levels returned to vehicle levels after NGF treatment. However, the phosphorylation of NGF receptor TrkA was dramtically decreased in NGF No-treated CMV/hTMP21 transfectants compared with vehicle transfectants, and increased in NGF treated CMV/hTMP21 transfectants. In TrkA downstream signaling pathway, the phosphorylation level of ERK was also decreased in CMV/hTMP21 transfectants, while the phosphorylation of Akt was increased in the same transfectants. Furthermore, NGF treatment induced the increase of phosphorylation level of Akt and ERK in CMV/hTMP21 transfectants. Therefore, these results suggested that over-expression of TMP21may simultaneously induce the up-regulation of $p75^{NTR}$/RhoA expression and the down-regulation of TrkA/ERK phosphorylation through the inhibition of ${\gamma}$-secretase activity.

• Clinical and Experimental Reproductive Medicine
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• v.34 no.3
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• pp.179-188
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• 2007

Objectives: Many neurological diseases are known to be caused by expansion of trinucleotide repeats (TNRs). It is hard to diagnose the alteration of TNRs with single cell level for preimplantation genetic diagnosis (PGD). In this study, we describe methods optimized for PGD of TNRs related diseases such as Huntington's disease (HD), spinocerebellar ataxia 3 (SCA3) and fragile X syndrome (FXS). Methods: We performed the preclinical assays with heterozygous patient's lymphocytes by single cell PCR strategy. Fluorescent semi-nested PCR and fragment analysis using automatic genetic analyzer were applied for HD and SCA 3. Whole genome amplification with multiple displacement amplification (MDA) method and fluorescent PCR were carried out for FXS. Amplification and allele drop-out (ADO) rate were evaluated in each case. Results: The fluorescent semi-nested PCR of single lymphocyte showed 100.0% of amplification and 14.0% of ADO rate in HD, and 94.7% of amplification and 5.6% of ADO rate in SCA3, respectively. We could not detect the PCR product of CGG repeats in FXS using the fluorescent semi-nested PCR alone. After applying the MDA method in FXS, 84.2% of amplification and 31.3% of ADO rate were achieved. Conclusions: Fluorescent semi-nested PCR is a reliable method for PGD of HD and SCA3. The advanced MDA method overcomes the problem of amplification failure in CGG repeats of FXS case. Optimization of methods for single cell analysis could improve the sensitivity and reliability of PGD for complicated single gene disorders of TNRs.