• Korean Journal of Environment and Ecology
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• v.23 no.5
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• pp.431-438
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• 2009

The main purpose of this research is to prepare and provide basic materials for the propagational strategy of eelgrass by investigating on the morphological adaptation of Korean Zostera marina to ocean currents. An eelgrass plant mainly consists of rhizome, leaf sheath, leaves and roots. The rhizome is the horizontal stem of the plant that serves as the backbone from which the leaves and roots emerge. The leaf sheath is the bundle at the base of the leaves that holds the leaves together, protecting the meristem, the primary growth point of the shoot. Leaves originate from a meristem which is protected by a sheath at the actively growing end of the rhizome. As the shoot grows, the rhizome elongates, moving across or within the sediment, forming roots as it progresses. The aggregated leaves from the leaf sheath are found to have two cell layers on one side and multiple layers of airy tissues called aerenchyma on the other. The aerenchyma tissues are developed in multi-layered cell structures surrounding the veins which are formed in the leaf sheath. Generative shoots are made of rhizomes, which are circular or ovoidal, stem, and spathe and spadix. The transverse section of rhizome and the stem and central floral axis is found to be circular, ovoid and in the shape of convex respectively, and the vascular bundle, which is a part of transport system, has one large tube in the center and two small tubes on both sides. The layers of collenchyma cells numbered from 12 to 15 in the stem, and from 7 to 12 in the rhizome. The seed coat is composed of sclereids, small bundles of sclerenchyma tissues, which prevent the influx of sea water from the outside and help endure the environmental stress. In conclusion, alternative multi-layer structure in circular, convex type aggregated leaf base are interpreted to morphological adaption as doing tolerable elastic structure through movement of seawater. The generative shoots develop long slim stem and branches in circular or ovoidal shapes to minimize the adverse impacts of sea current, which can be interpreted as the plant's morphological adaptation to its environment.

• The Journal of the Korean bone and joint tumor society
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• v.3 no.2
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• pp.80-88
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• 1997

Malignant tumors of extremeties involving major neurovascular structures have been treated by amputation. However recent development of diagnostic tools(CT, MRI etc.), surgical techniques, anticancer chemotherapeutic agents, and radiation techniques allow surgeons to treat malignant tumors in the limb without amputation. It has been reported that a local application of low-heat to the tissue with tumor can kill tumor cells. It is, however, not known if the attendant neural and vascular injuries may be recovered. The present study was, therefore, undertakn to address this question in rabbit sciatic nerves. A low-heat injury to the sciatic nerve was induced by perfusing the nerve with $60^{\circ}C$ saline for 30 minutes and the courses of functional and morphological recovery of the nerve were evaluated for 16 weeks. The results are summerized as follows : 1. In the electromyographic nerve conduction test the average amplitude was markedly attenuated at 4 and 8 weeks after the low-heat treatment, but it progressively increased to the level 89.5% of the control at 16 week post-treatment. The average latency in the control group was 0.62 msec. The latency in the experimental group was much longer than this at 4 and 8 week post-treatment, but it progressively reverted to the control level, showing 0.622 msec at 16 weeks. 2. In the needle EMG, many fibrillation potentials and positive sharp waves were appeared until 8 weeks post-treatment. After 16 weeks, however, no fibrillation potential was observed. 3. In the early phase of post-treatment period, the myelinated nerve fibers contained many vacuoles and the number of myelinated nerve fibers appeared to be considerably reduced. However, as time goes myelinated nerve fibers were regenerated, such that after 16 weeks the histologic appearance of the nerve was similar to that of the control group.

• The Journal of the Korean bone and joint tumor society
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• v.18 no.1
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• pp.7-13
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• 2012

Purpose: The purpose of this study is to compare general survival rate and survival rate according to expectable prognostic factors by analyzing the result of treating a patient of squamous cell carcinoma. Materials and Methods: From Mar. 1999 to Feb. 2011, 151 patients were pathologically confirmed as squamous cell carcinoma of limbs and body in our hospital, and among those patients, 51 patients underwent the surgical treatment. This study included 41 patients who underwent the surgical treatment and were followed-up for more than 12 months. The mean age of population was 64.4 years. 31 males and 10 females were included. Wide excision with following skin grafts or flaps for reconstruction (29 cases) was mostly performed, but amputation (12 cases) was also performed for cases with extremities where resection margin was difficult to obtain and cases with neural or vascular invasion. 8 patients underwent chemotherapy or radiotherapy after resection, and 33 underwent the operation only. Stages were classified by AJCC Classification, survival rate was calculated by Kaplan-Meier method and survival rate of groups was compared by Log-rank test. For the expectable prognostic factors related to survival rate, location of primary lesion, cause of disease, pathologic grade, staging, surgical method, additional anticancer therapy were examined and each survival rate was compared. Results: The average follow-up period was 65.2 (12-132) months. Thirty patients survived out of 41 patients till last follow up. The overall survival rate in 5 years was 77%. Three cases (7.3%) had local recurrence, and 7 cases (17.0%) had metastasis. The average period of recurrence from operation was 27 (18-43) months. Possible prognostic factors such as location of primary lesion, cause of disease, pathologic grade, staging, additional anticancer therapy showed no significant difference in survival rates. However, patients with amputation showed significantly lower survival rate than those with wide excision. Conclusion: In analysis the results of treating 41 cases of squamous cell carcinoma, the overall 5-year survival rate was 77%. And, among the several prognostic factors, only the surgical method was significant statistically.

• The korean journal of orthodontics
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• v.31 no.1 s.84
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• pp.121-136
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• 2001

This study was performed to analyse the expression of VEGF and it's receptor(VEGFR) in the tension side of the periodontal ligament following orthodontic tooth movement. Upper first molars of Sprague-Dawley rats were moved medially using closed coil spring for 1, 2, 24 hours and 3, 7, 14 days. H&E staining, immunohistochemical staining and in situ hybridization methods were used to analyse the change of the expression of VEGF and VEGFR. The results from this study were as follows : 1. Following tensional force, periodontal ligament showed elongation of fibers, compression and congestion of vessels and regional hemorrhage. These tissue changes were recovered within 3 days of force application. New bone formation was seen after 3 days of force application and continued for the remaining experimental periods. 2. Following tensional force, VEGF and VEGF mRNA expression was increased in the periodontal ligament cells, osteoblasts and cementoblasts. This change was followed by increased vasculature in the periodontal ligament. 3. After 3 days of tensional force, VEGF and VEGF mRNA expression was confined mainly to the osteopaths and the periodontal ligament cells adjacent to the alveolar bone. After 2 weeks of force application, VEGF and VEGF mRNA expression was reduced to the level of control sample. 4. VEGFRs(Flt-1, Flk-1) showed similar expression pattern and it's expression was mainly seen in the endothelial cells and osteoblasts. Following tensional force VEGFR expression was increased in the endothelial cells and osteoblasts. In conclusion, in the tension side of the penodontal ligament, ligament cells, osteoblast and cementoblast showed increased expression of VEGF & VEGF mRNA. It preceded the increase of vasculature and new bone formation. The increased expression of VEGF mRNA in cementoblast may induce periodontal vessels, which distribute mainly the bone side half of periodontal ligament, grow in the direction of tensional force. Increased expression of VEGFR & VEGFR mRNA not only in endothelial cell but in osteoblast, osteocyte and periodontal cells showed VEGF acts not only in paracrine manner but in autocrine one.

• Journal of Gastric Cancer
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• v.5 no.3 s.19
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• pp.191-199
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• 2005

Background: Though infections of Helicobacter pylori (H. pylori) are closely associated with activation of host angiogenesis, the underlying mechanisms, as well as the strategy for its prevention, have not been identified. Here, we investigated a causal role of H. pylori infection in angiogenesis of gastric mucosa and a potent inhibitory effect of a gastric proton pump inhibitor (PPI) on the gastropathy. Materials and Methods: A comparative analysis of CD 34 expression in tissues obtained from 20 H. pylori-associated gastritis and 18 H. pylori-negative gastritis patients was performed. Expression of $HIF-1{\alpha}$ and VEGF were tested by using RT-PCR. To evaluate the direct effect of H. pylori infection on differentiation of endothelial HUVEC cells, we carried out an in vitro angiogenesis assay. Results: H. pyfori-associated gastritis tissues showed significantly higher density of $CD34^+$ blood vessels than did H. pylori-negative gastritis tissues, and the levels were well correlated with expressions of $HIF-1{\alpha}$. Conditioned media from H. pylori-infected gastric mucosal cells stimulated a tubular formation of HUVEC cells. We also found a significant inhibitory effect of PPI, an agent frequently used for H. pylori eradication, on H. pylori-induced angiogenesis. This drug effectively inhibited the phosphorylation of MAP kinase ERK1/2, which is a principal signal for H. pylori-induced angiogenesis. Conclusion: The fact that PPls can down-regulate H. pylori-induced angiogenesis suggest that anti-angiogenic treatment using PPI may be a preventive approach for H. pylori-associated carcinogenesis.

• Tuberculosis and Respiratory Diseases
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• v.41 no.6
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• pp.604-615
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• 1994

Background: Analysis of cells in bronchoalveolar lavage(BAL) fluid had been used to predict the histologic changes of the bronchioles and alveoli in patients with interstitial lung diseases(ILD). Definitive diagnosis can be a1so made in some cases of ILD, such as histiocytosis. However, there are a few data of the cellular components in BAL fluid in normal Korean individuals and in patients with ILD. In order to evaluate the role of the cellular analysis of BAL fluid in prediction of alveolitis and differential diagnosis among ILDs, we compared the cellular components in BAL fluid from 50 normal individuals and 86 ILD patients. Method: BAL was performed by instillation and retrievement of normal saline with fiberoptic bronchoscopy. The cell number was counted by Hemocytometer. Differential count was done up to 500 cells on slides prepared by Diff-Quik stain and non-specific esterase stain. We compared the recovery rate(RR), cell numbers(CN), and percentages of each cellular components(CP). Results: The results were as follows: 1) There was no difference in RR, CN and CP between the normal smoker group and normal non-smoker group. 2) Total cell numbers recoverd in BAL fluid increased in collagen vascular diseases(CVD), hypersensitivity pneumonitis(HP), idiopathic pulmonary fibrosis(IPF), and miliary tuberculosis(Mil TBC) groups. 3) The percentage of lymphocytes increased in HP, IPF and Mil TBC groups. Macrophage percentages increased in HP, IPF, and Mil TBC groups. Neutrophil percentages were increased in CVD, HP, IPF and Mil TBC groups. Eosinophil percentages were increased in HP, IPF and Mil TBC groups. The numbers of each cells showed same findings as the percentages did. Conclusion: The analysis of cellular components of BAL fluid can predict the presence of alveolitis in many cases of ILDs. However, It was not helpful in differential diagnosis among ILDs.

• Tuberculosis and Respiratory Diseases
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• v.50 no.5
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• pp.540-548
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• 2001

Backgrounds : Because ventilator-induced lung injury is partly dependent on the intensity of vascular flow, we hypothesized that hypothermia may attenuate the degree of such an injury through a reduced cardiac output. Methods : Twenty-seven male Sprague-Dawley rats were randomly assigned to normothermia ($37{\pm}1^{\circ}C$)-injurious ventilation (NT-V) group (n=10), hypothermia ($27{\pm}1^{\circ}C$)-injurious ventilation (HT-V) group (n=10), or nonventilated control group (n=7). The two thermal groups were subjected to injurious mechanical ventilation for 20 min with peak airway pressure 30 cm $H_2O$ at zero positive end-expiratory pressure, which was translated to tidal volume $54{\pm}6\;ml$ in the NT-V group and $53{\pm}4\;ml$ in the HT-V group (p>0.05). Results : Pressure-volume (P-V) curve after the injurious ventilation was almost identical to the baseline P-V curve in the HT-V group, whereas it was shifted rightward in the NT-V group. On gross inspection, the lungs of the HT-V group appeared smaller in size, and showed less hemorrhage especially at the dependent regions, than the lungs of the NT-V group. [Wet lung weight (g)/body weight (kg)] ($1.6{\pm}0.1$ vs $2.4{\pm}1.2$ ; p=0.014) and [wet lung weight/dry lung weight] ($5.0{\pm}0.1$ vs $6.1{\pm}0.8$ ; p=0.046) of the HT-V group were both lower than those of the NT-V group, while not different from those of the control group($1.4{\pm}0.4$, $4.8{\pm}0.4$, respectively). Protein concentration of the BAL fluid of the HT-V group was lower than that of the NT-V group($1,374{\pm}726\;ug/ml$ vs $3,471{\pm}1,985\;ug/ml$;p=0.003). Lactic dehydrogenase level of the BAL fluid of the HT-V group was lower than that of the NT-V group ($0.18{\pm}0.10\;unit/ml$ vs $0.43{\pm}0.22\;unit/ml$;p=0.046). Conclusions : Hypothermia attenuated pulmonary hemorrhage, permeability pulmonary edema, and alveolar cellular injuries associated with injurious mechanical ventilation, and preserved normal P-V characteristics of the lung in rats.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.835-845
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• 1998

Background: Silica-induced lung diseases is characterized by the accumulation of inflammatory cells at early stage and fibrosis in pulmonary parenchyma and interstitium at late stage. As a consequence of inflammation, silicosis is accompanied with the expansion of interstitial collagen and the formation of fibrotic nodule. In this process, several kinds of lung cells produce cytokines which can amplify and modulate pulmonary fibrosis. The alveolar macrophage is a potent source of proflammatory cytokines and growth factor. But in the process of silicotic inflammation and fibrosis, there are many changes of the kinetics in cytokine network. And the sources of cytokines in each phase are not well known. Method: 2.5 mg of silica was instillated into the lung of C57BL/6J mice. After intratracheal instillation of silica, the lungs were removed for imunohistochemical stain at 1, 2, 7 day, 2, 4, 8, 12 week, respectively. We investigated the expression of IL-1$\beta$, IL-6, TNF-$\alpha$ and TGF-$\beta$ in lung tissue. Results: 1) The expression of IL-6 increased from 1 day after exposure to 8 weeks in vascular endothelium. Also peribronchial area were stained for IL-6 from 7 days and reached the peak level for 4 weeks. 2) The IL-1 $\beta$ was expressed weakly at the alveolar and peribronchial area through 12 weeks. 3) The TNF-$\alpha$ expressed strongly at alveolar and bronchial epithelia during early stage and maintained for 12 weeks. 4) TGF-$\beta$ was expressed strongly at bronchial epithelia and peribronchial area after 1 week and the strongest at 8 weeks. Conclusion: The results above suggests IL-6, TNF-$\alpha$ appear to be a early inflammatory response in silica induced lung fibrosis and TGF-$\beta$ play a major role in the maintenance and modulation of fibrosis in lung tissue. And the regulation of TNF-$\alpha$ production will be a key role in modultion of silica-induced fibrosis.

• Journal of Bio-Environment Control
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• v.27 no.3
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• pp.231-238
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• 2018

Chlorophyll fluorescence, chlorophyll content, graft-taking and growth of grafted cucumber seedlings as affected by photosynthetic photon flux (PPF) of LED lamps were analyzed in this study. Four PPF levels, namely 25, 50, 100, $150{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ were provided to investigate the effect of light intensity on the chlorophyll fluorescence, chlorophyll content, graft-taking and growth of grafted cucumber seedlings. Air temperature, relative humidity, and photoperiod for graft-taking were maintained at $25^{\circ}C$, 90%, $16h{\cdot}d^{-1}$, respectively. Maximum quantum yield (Fv/Fm) of rootstock as affected by PPF was found to be 0.84-0.85 and there was no significant change in Fv/Fm. Even though Fv/Fm of scion measured at 2 days after grafting was lowered to 0.81-0.82, after then it gradually increased with increasing PPF. At 4 days after grafting, the chlorophyll content extracted from scion increased with increasing PPF. Graft-taking ratio of grafted cucumber seedlings was 90-95% as PPF was ranged from $25{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ to $100{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. However, the graft-taking ratio of grafted seedlings healed under PPF of $150{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ was decreased to 80%. Maximum PPF measured required for smooth joining of rootstock and scion was assumed to be $100{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. At healing stage of grafted cucumber seedlings, Fv/Fm of scion decreased and at least two days after grafting were required for rooting of grafted seedlings. Chlorophyll fluorescence response of rootstock and scion was linked to light irradiation. Therefore, it was concluded that physical environment including light and humidity during healing process of grafted seedlings should be controlled more precisely to facilitate root formation and to prevent scion from lowering Fv/Fm. Further studies are required to investigate the effects of root development and joining of vascular bundles of grafted seedlings on the chlorophyll content of scion.

• Investigative Magnetic Resonance Imaging
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• v.2 no.1
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• pp.96-103
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• 1998

Purpose : To assess the clinical utility of turbo contrast-enhanced magnetic resonance angiography(CE MRA) in the evaluation of the aortic arch and its major branches and to compare the image quality of CE MRA among different coils used. Materials and Methods : Turbo three-phase dynamic CE MRA encompassing aortic arch and its major branches was prospectively performed after manual bolus IV injection of contrast material in 29 patients with suspected cerebrovascular diseases at 1.0T MR unit. the raw data were obtained with 3-D FISH sequence (TR 5.4ms, TE 2.3ms, flip angle 30, slab thickness 80nm, effective slice thickness 4.0mm, matrix size $100{\times}256$, FOV 280mm). Total data acquisition time was 4. to 60 seconds. We subjectively evaluated the imge quality with three-rating scheme : "good" for unequivocal normal finding, "fair" for relatively satisfactory quality to diagnose 'normal' despite intravascular low signal, and "poor" for equivocal diagnosis or non-visualization of the origin or segment of the vessels due to low signal or artifacts which needs catheter angiography. At the level of the carotid bifurcation, it was compared with conventional 2D-TOF MRA image. Overall image quality was also compared visually and quantitatively by measuring signal-to-noise ratios (SNRs) of the ascending aorta, the innominate artery and both common carotid arteries among the three different coils used(CP body array(n=12), CP neck array(n=9), and head-and-neck(n=8). Results : Demonstration of the aortic arch and its major branches was rated as "good" in 55% (16/29) and "fair" in 34%(10/29). At the level of the carotid bifurcation, image quality of turbo CE MRA was same as or better than conventional 2D-TOF MRA in 65% (17/26). Overall image quality and SNR were significantlygreater with CP body array coil than with CP neck array or head-and-neck coil. Conclusions : Turbo CE MRA can be used as a screening exam in the evaluation of the major branches of the aortic arch from their origin to the skull base. Overall imagequality appears to be better with CP body array coil than with CP neck array coil or head-and-neck coil.