• Restorative Dentistry and Endodontics
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• v.33 no.6
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• pp.507-517
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• 2008

There are considerable in vitro and in vivo evidences for remineralization and demineralization occurring simultaneously in incipient enamel caries. In order to "heal" the incipient dental caries, many experiments have been carried out to determine the optimal conditions for remineralization. It was shown that remineralization is affected by different pH, lactic acid concentrations, chemical composition of the enamel, fluoride concentrations, etc. Eighty specimens from sound permanent teeth without demineralization or cracks, 0.15 mm in thickness, were immersed in lactic acid buffered demineralization solutions for 3 days. Dental caries with a surface zone and subsurface lesion were artificially produced. Groups of 10 specimens were immersed for 10 or 12 days in lactic acid buffered remineralization solutions consisting of pH 4.3 or pH 6.0, and 100, 50, 25, or 10 mM lactic acid. After demineralization and remineralization, images were taken by polarizing microscopy (${\times}100$) and micro-computed tomography. The results were obtained by observing images of the specimens and the density of the caries lesions was determined. 1.As the lactic acid concentration of the remineralization solutions with pH 4.3 was higher, the surface zone of the carious enamel increased and an isotropic zone of the subsurface lesion was found. However, the total decalcification depth increased at the same time. 2.In the remineralization solutions with pH 6.0, only the surface zone increased slightly but there was no significant change in the total decalcification depth and subsurface zone. In the lactic acid buffer solutions with the lower pH and higher lactic acid concentration, there were dynamic changes at the deep area of the dental carious lesion.

• Restorative Dentistry and Endodontics
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• v.33 no.6
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• pp.537-544
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• 2008

Polymerase chain reaction (PCR) can detect bacteria more rapidly than conventional plate counting. However DNA-based assays cannot distinguish between viable and dead cells due to persistence of DNA after cells have lost their vitality. Recently, propidium monoazide (PMA) treatment has been introduced. The purpose of this study is to evaluate the applicability of the PMA treatment and real-time PCR method for cell counting in comparison with plate counting and to evaluate the antibacterial efficacy of 2% CHX on E. faecalis using PMA treatment in combination with real-time PCR. Firstly, to elucidate the relationship between the proportion of viable cells and the real-time PCR signals after PMA treatment, mixtures with different ratios of viable and dead cells were used. Secondly, relative difference of viable cells using PMA treatment in combination with real-time PCR was compared with CFU by plate counting. Lastly, antibacterial efficacy of 2% CHX on E. faecalis was measured using PMA treatment in combination with real-time PCR. The results were as follows : 1. Ct value increased with decreasing proportion of viable E. faecalis. 2. There was correlation between viable cells measured by real-time PCR after PMA treatment and CFU by plate counting until Optical density (OD) value remains under 1.0. However, viable cells measured by real-time PCR after PMA treatment have decreased at 1.5 of OD value while CFU kept increasing. 3. Relative difference of viable E. faecalis decreased more after longer application of 2% CHX.

• Journal of Nutrition and Health
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• v.48 no.2
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• pp.167-179
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• 2015

Purpose: This study was conducted to evaluate the association between intakes of potassium, magnesium, and calcium and diet quality in ischemic stroke patients. Methods: This study analyzed data from 285 subjects recruited from February 2011 to August 2014 in Seoul, Korea. Nutrition intakes were obtained from a semi-quantitative food frequency questionnaire composed of 111 food items. The subjects were divided into 4 groups by quartiles according to intakes of potassium, magnesium, and calcium. Index of Nutritional Quality (INQ), Mean Adequacy Ratio (MAR), and DQI-International (DQI-I) were analyzed for assessment of diet quality. Results: We found a positive association of intakes of these three minerals with MAR and DQI-I after adjustment for age, sex, education level, smoking, atrial fibrillation, and total energy intake. However, total moderation of DQI-I score in the Q4 group was significantly lower than that of the Q1 group. The age, sex, education level, and smoking, atrial fibrillation, and total energy intake-adjusted odds ratios of extensive cerebral atherosclerosis were inversely associated with intake of magnesium (Ptrend = 0.0204). However, this association did not exist with intakes of potassium and calcium. Conclusion: Potassium, magnesium, and calcium rich and high quality diet could be associated with decreased risk of ischemic stroke, in part, via effect on extensive cerebral atherosclerosis.

• Korean Journal of Materials Research
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• v.15 no.3
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• pp.161-165
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• 2005

We investigated selective dry etching of GaAs over AlGaAs and InGaP in high density planar inductively coupled $BCl_3/SF_6$ plasmas. The process parameters were ICP source power (0-500 W), RE chuck power (0-30W) and gas composition $(60-100\%\;BCl_3\;in\;BCl_3/SF_6)$. The process results were characterized in terms of etch rate, selectivities of GaAs over AlGaAs and InGaP, surface morphology, surface roughness and residues after etching. $BCl_3/SF_6$ selective etching of GaAs showed quite good results in this study. Selectivities of GaAs $(GaAs:AlGaAs\~36:1,\;GaAs:InGaP\~45:1)$ were superior at $18BCl_3/2SF_6$, 20 W RF chuck power, 300 W ICP source power and 7.5 mTorr. Addition of $(5-15\%)SF_6\;to\;BCl_3$ produced relatively high selectivities of GaAs over AlGaAs and InGaP during etching due to decrease of etch rates of AlGaAs and InGaP (boiling points of etch products: $AlF_3\~1300^{\circ}C,\;InF_3>1200^{\circ}C$ at atmosphere) at the condition. SEM and AFM data showed slightly sloped sidewall and somewhat rough surface$(RMS\~9nm)$. XPS study on the surface of processed GaAs proved a very clean surface after dry etching. It shows that planar inductively coupled $BCl_3/SF_6$ plasmas could be a good candidate for selective dry etching of GaAs over AlGaAs and InGaP.

• Weed & Turfgrass Science
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• v.7 no.3
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• pp.275-282
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• 2018

Miscanthus species are known as a genus of eco-friendly and low-maintenance cost ornamental grasses. Plug and cutting methods were tested for multi-propagation of most promising ornamental Miscanthus species in greenhouse and field plot. The plug formation period with three different cell sizes with four cultivars (M. sinensis 'Andersson', 'Strictus', 'Gracillimus', 'Variegatus') were evaluated the seedling development stages with two irrigation types of the over-head and the bottom watering in greenhouse and field plot afterward during 2015-2016 season. In seedling plug test, the size of tray cell affected the plug formation. Bottom irrigation resulted positively on plant height, weight, root and tiller development compared with the over-head irrigation. Plug cell size affected the plant growth in the field after transplanting. All of the 3 Miscanthus species showed higher rates of successful propagation at the lower nodes before inflorescence formation (vegetative growth stage). To analyze the survival factors of M. xgiganteus cutting, the cutting time, node part, and culm diameter were tested as independent variables with the binary logistic model. The survival probability was influenced by node part and culm diameter significantly. The third and fifth node parts showed 0.12 (8X higher failure probability) and 0.02 (50X higher failure probability) times less survival probability. It means the survival probability will be increased by using older and lower part of cuttings during a vegetative growth stage before inflorescences of M. xgiganteus.

• Journal of Chest Surgery
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• v.29 no.10
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• pp.1055-1065
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• 1996

This experiment was undertaken to assess the effect of nitric oxide, isosorbide dinitrate, and sodium nitroprusside, which are known to increase coronary flow by vasodilation and to improve the cardiac function of an ischemic heart The experiment was carried out to investigate the effect of nitric oxide on the coronary artery of an ischemic rat myocardium using isolated constant pressure Langendorfr system. The experimental parameters were lactate and CK-MB for the frozen myocardium and coronary flow. the quantity of coyonary flow, left ventricular developed pressure (LVDP), and dp/dt. The experimental groups were decided as control group (Group I), nitric oxide group (Group II), Iso orbide dinitrate group (Group III) and sodium nitroprusside group (Group IV). Statistical analysis was performed using repeated measured analysis of variance and 2tudent t-test The results were as follows: 1 . The lactic acid contents of group II and IV were less than other groups for the frozen myocardium at preischemic state (p< 0.0025), whereas the determined coronary flows were higher. 2. In the ratio of produced lactic acid between the preischemia and reperfusion for the coronary flow, group II and IV exhibitrod less value than others (p< 0.005). 3. Group II and III were less than others in the coronary flow for the quantity of CK-MB, but or the frozen myocardium, group II and IV were less. 4. Group II and IV showed higher coronary flow compared to others throughout entire experimental period (p< 0.005). 5. Group II was highest at the preischemic state for the left ventricular developed pressure. 6. The +maximal dp/dt of group II was highest compared to others. 7. Group I exhibi ed the highest recovery rate of coronary flow between prelschemla and reperfusion. 8. The(-dp/dt)1(+dp/dt) ratio was 116%, 100%, 100%, and 55% for the 4 groups, respectively And the recovery rate of total dp/dt was 34%, 67%, 51%, and 76% for the four groups, respectively.

• Journal of Chest Surgery
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• v.40 no.7 s.276
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• pp.492-498
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• 2007

Background: Malignant pleural effusion is a common condition in neoplastic patients and palliative therapy is the usual treatment. Talc has been generally accepted to be the most effective sclerosant for chemical pleurodesis, but the optimal route of administration remains controversy. We compared the results of video-assisted thoracoscopic talc poudrage (VTP) with administering a bedside talc slurry through a chest tube (BTS) for the treatment of malignant pleural effusion. Material and Method: From December 2004 to May 2006, 20 patients with malignant pleural effusion underwent chemical pleurodesis via VTP (group A, n=10), and BTS (group B, n=10). Result: The durations of chest tube placement after the procedure were $7.0{\pm}4.0$ days (group A) and $6.7{\pm}3.6$ days (group B). The hospital stays were $24.3{\pm}9.4$ days (group A) and $30.7{\pm}21.5$ days (group B), respectively. The symptoms of dyspnea were much more improved in group A (p-value=0.014) after discharge (mean f/u group $A=8.5{\pm}2.2$ months, group B $8.0{\pm}7.4$ months). The collapsed portions of lung were better expanded in group A than in group B (p-value=0.011). Conclusion: We recommend VTP for the selected patients with malignant pleural effusion because of the advantages of dissecting the fibrous peel to relieve the atelectasis and dyspnea, and excising the pleura for diagnosis with direct viewing of the lesion.

• Journal of Chest Surgery
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• v.42 no.4
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• pp.502-508
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• 2009

Background: Rib fractures are the most common injuries that are caused by blunt chest trauma. However, fractures of the costal cartilage generally go unnoticed on chest X-rays unless they involve a calcified cartilage. For this reason, the sensitivity of conventional radiography for detecting rib fractures is low, and especially those involving the cartilaginous part of the rib. Thus, we have evaluated the usefulness of ultrasonography for detecting fractures of the costal cartilage that were overlooked on the conventional radiographs of patients who suffered minor blunt chest traumas. Material and Method: A total of 45 patients who suffered minor blunt chest trauma and who had no evidence of rib fractures or other major fractures on conventional radiographs were admitted for ultrasonography between April 2008 and March 2009. There were 24 women and 21 men, and the mean age of the patients was 50.4$\pm$15.91 years (range: 17$\sim$76 years). They were examined for the detection of fractures of the costal cartilage by performing ultrasonography with a 7.5-MHz linear transducer. Result: A total of 30 patients (67%) had fractures of the costal cartilage, whereas 15 patients (33%) had no evidence of chondral rib fractures. The mean number of fracture sites of the fractured costal cartilage was 1.6$\pm$0.81 (range: 1$\sim$4 sites) in 30 patients. Periosteal hematoma was the most common finding associated with fractures of the costal cartilage (n=7, 17%), followed by sternum fracture (n=5, 12%). However, periosteal hematoma was noticed in 1 patient (2%) who was without fracture of the costal cartilage, and sternum fracture was noticed in 1 patient (2%) who was without fractures of the costal cartilage. Conclusion: The results of this study suggest that ultrasonography may be a useful imaging modality for detecting fractures of the costal cartilage that are overlooked on the conventional radiographs of patients who suffer minor blunt chest trauma.

• Journal of Chest Surgery
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• v.43 no.4
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• pp.394-398
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• 2010

Background: The overexpression of transforming growth factor-beta 1 receptor II (TGF-${\beta}1$RII) and transforming growth factor-beta 1 (TGF-${\beta}1$) ligand may be involved in the formation of a bulla. In this study, we tested if serum TGF-${\beta}1$ ligand levels correlated with the expression level of TGF-${\beta}1$RII and TGF-${\beta}1$ in bullous tissues from patients with spontaneous pneumothorax. Material and Method: Bullous lung tissues and blood samples were obtained from 19 patients with spontaneous pneumothorax, 18 males and 1 female, aged 17 to 35 years old. The bullous tissues were obtained by video-assisted thoracic surgery (VATS), fixed in formalin, embedded in paraffin, and cut into $5{\sim}6{\mu}m$ thick slices. Sections were immunohistochemically stained with primary antibodies against TGF-${\beta}1$ or TGF-${\beta}1$RII, and serum levels of TGF-${\beta}1$ in patients and normal controls was measured by enzyme-linked immunosorbent assay (ELISA). Result: Of the 19 patients, 16 were TGF-${\beta}1$ positive and 10 were TGF-${\beta}1$RII positive. Among the 16 TGF-${\beta}1$ positives, 9 were also TGF-${\beta}1RII$ positive. As seen previously, strong immunohistochemical staining of TGF-${\beta}1$RII and TGF-${\beta}$ was detected in the boundary region between the bullous and normal lung tissues. Average TGF-${\beta}1$ blood levels of both TGF-${\beta}1$ and TGF-${\beta}1$RII positive patients was $38.36{\pm}16.2ng/mL$, and that of five controls was $54.06{\pm}15ng/mL$. Conclusion: These results suggest that overexpression of TGF-${\beta}1$ and TGF-${\beta}1$RII expression may be involved in the formation of bullae. TGF-${\beta}1$ blood levels in patients with primary spontaneous pneumothorax is lower than normal people, suggesting that the high level of local TGF-${\beta}1$ expression in the bullous tissue region, but not in the whole blood, may contribute more in the formation of bullae.

• Journal of Chest Surgery
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• v.42 no.4
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• pp.447-455
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• 2009

Background: Prosthetic valve endocarditis usually presents with clinical symptoms that are more severe than native valve endocarditis, and prosthetic valve endocarditis shows the spread of infection into the surrounding tissue as well as into the superficial endocardial layers. The postoperative prognosis is especially poor for valve re-replacement for the cases of active endocarditis that are unable to receive a full-course of pre-antibiotic therapy due to complications and the ensuing clinical aggravation. The aim of this study was to evaluate the clinical profiles, laboratory findings and mid-term surgical results of active prosthetic valve endocarditis. Material and Method: Among the 276 surgically treated infective endocarditis patients who were treated during the period from January 1998 to July 2008, 31 patients were treated for prosthetic valve endocarditis. Among these patients, 24 received surgical treatment for an 'active' state, and they were selected for evaluation. Result: The most frequently encountered symptom was a febrile sensation. Eight cases (33.3%) were accompanied by systemic thromboembolism, among which 5 cases (20.8%) had an affected central nervous system. 'Vegetations' were most commonly found on transesophageal echocardiography, and the 'Staphylococcus species' were the most frequent pathogens. There were 4 deaths in the immediate postoperative period, and an additional 4 patients died during the follow-up period (Mean$\pm$SD, 42.1$\pm$36.9 months). The cumulative survival rate was 79% at 1 year, 73% at 3 years, 66% at 5 year, and 49.5% at 7 years. Conclusion: The cases of active prosthetic valve endocarditis that were unable to receive a full course of preoperative antibiotics therapy generally have a poor prognosis. Nevertheless, early surgery and extensive resection of all the infected tissue is pivotal in improving the survival rate of patients with surgically treated active prosthetic valve endocarditis.