• Journal of the korean academy of Pediatric Dentistry
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• v.26 no.2
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• pp.399-415
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• 1999

From bacteria to mammalian cells, one of the most important mediators of intracellular signal transduction mechanisms which regulate a variety of intracellular processes is free calcium. In salivary acinar cells, elevation of intracellular calcium concentration ($[Ca^{2+}]_i$) is essential for the salivary secretion induced by parasympathetic stimulation. However, in addition to $[Ca^{2+}]_i$, gap junctions which couple individual cells electrically and chemically have also been reported to regulate enzyme secretion in pancreatic acinar cells. Since the plasma membrane of salivary acinar cells has a high density of gap junctions, and these cells are electrically and chemically coupled with each other, gap junctions may modulate the secretory function of salivary glands. In this respect, I planned to investigate the role of gap junctions in the modulation of salivary secretion and $[Ca^{2+}]_i$, using mandibular salivary glands of rats. In order to measure the salivary flow rate, fluid was collected from the cannulated duct of the isolated perfused rat mandibular glands at 2 min intervals. $[Ca^{2+}]_i$, was measured from the cells loaded with fura-2 by spectrofluorometry. The results obtained were as follows: 1. CCh-induced salivary secretion was reversibly inhibited by 1 mM octanol, a gap junction blocker. 2. CCh-induced increase in $[Ca^{2+}]_i$, was also reversed by the application of 1 mM octanol. 3. Octanol did not block the initial increase in $[Ca^{2+}]_i$ caused by CCh, which suggested that the reduction of $[Ca^{2+}]_i$, caused by gap junction blockade was not resulted from the inhibition of $Ca^{2+}$ release from intracellular $Ca^{2+}$ stores. 4. Addition of octanol during stimulation with $1{\mu}M$ thapsigargin, a potent microsomal ATPase inhibitor, reduced $[Ca^{2+}]_i$, to the basal level. This suggested that inhibition of gap junction permeability closed plasma membrane $Ca^{2+}$ channels. 5. 2,5-di-tert-butyl-1,4-benzohydroquinone (TBQ) generated $[Ca^{2+}]_i$ oscillations resulting from periodic influx of $Ca^{2+}$ via plasma membrane. The TBQ-induced $[Ca^{2+}]_i$ oscillations were stopped by the application of 1mM octanol which implicated that gap junctions modulate the permeability of plasma membrane $Ca^{2+}$ channels. 6. Glycyrrhetinic acid, another well known gap junction blocker, also inhibited CCh-induced salivary secretion from rat mandibular glands. These results suggested that gap junctions play an important role in the modulation of fluid secretion from the rat mandibular glands and this was probably due to the inhibition of $Ca^{2+}$ influx through the plasma membrane $Ca^{2+}$ channels.

• Journal of Korean Society of Rural Planning
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• v.24 no.3
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• pp.73-86
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• 2018

Agricultural or rural landscape provides various ecosystem services. However, the ecosystem services function is declining due to various environmental problems such as climate change, land use change, stream intensification, non-point pollution and garbage. The A1B scenario predicts that the mean air temperature of South Korea will rise $3.8^{\circ}C$ degrees celsius in 2100. Agricultural sector is very vulnerable to climate change, so it must be thoroughly predicted and managed. In Korea, the facility horticulture complex is 54,051ha in 2016 and is the 3rd largest in the world(MAFRA, 2014). Facilities of horticultural complexes are reported to cause problems such as groundwater decrease, vegetation and insects diversity reduction, landscapes damage and garbage increase, compared with the existing land use paddy fields. Heat island phenomenon associated with climate change is also accelerated by the high heat absorption of horticultural sites. Therefore, we analyzed the heat island phenomenon occurring in the facility of horticultural complex in Korea. As an improvement measurement, I examined how much air temperature is reduced by putting the channel and the open space. In the case of the Buyeo area, the Computational Fluid Dynamics (CFD) simulation was analyzed for the average summer temperature distribution in the current land use mode at $38.9^{\circ}C$. As an improvement measurement, CFD simulation after 10% of 6m water channel was found to have an effect of lowering the summer temperature of about $2.7^{\circ}C$ compared with the present average of $36.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $34.7^{\circ}C$, which is $4.2^{\circ}C$ lower than the present. For the Jinju area, CFD simulations were analyzed for the average temperature of summer at $37.8^{\circ}C$ in the present land use pattern. As an improvement measure, CFD simulations after 10% of 6m water channel were found to have an effect of lowering the summer temperature of about $2.6^{\circ}C$ compared to the current average of $35.2^{\circ}C$. In addition, CFD simulations after analyzing 10% of the open space were analyzed at $33.9^{\circ}C$, which is $3.9^{\circ}C$ lower than the present. It can be said that the effect of summer temperature drop in open space and waterway has been proven. The results of this study are expected to be reflected in sustainable agriculture land use and used as basic data for government - level policy in land use planning for climate change.

• Radiation Oncology Journal
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• v.18 no.4
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• pp.321-328
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• 2000

Purpose :NOS2 induce NO Production and NO activate TGF-${\beta}$. The TGF-${\beta}$ is a inhibitor of NOS2. If this negative feedback mechanism operating in radiation pneumonitis model, NOS2 inhibitor may play a role in TGF-${\beta}$ suppression. We planned this study to evaluate the expression patterns of NO, NOS2 and TGF-${\beta}$ in vivo radiation pneumonitis model. Materials and Methods : Sixty sprague-Dawley rat were irradiated 5 Gy or 20 Gy. They were sacrificed 3, 7, 14, 28 and 56 days after irradiation. During sacrifice, we peformed broncho-alveolar lavage (BAL). The BAL fluids were centrifuged and supernatents were used for measure NO and TGF-${\beta}$, and the cells were used for RT-PCR. Results : After 5 Gy of radiation, NO in BAL fluid increased at 28 days in both lung and TGF-${\beta}$ in left lung at 56 days. NO increased in BAL fluid at 28 days in both lung after irradiation and TGF-${\beta}$ in right lung at 28-56 days after 20 Gy of radiation. After 5 Gy of radiation, NOS2 expression was increased in right lung at 14 days, in both lung at 28 days and in left lung at 56 days. TGF-${\beta}$ expression was reduced in both lung at 28 days and increased in left lung at 56 days. Conclusions :The Proposed feedback mechanism of NO, NOS2 and TGF-${\beta}$ was operated in vivo radiation pneumonitis model. At 56 days, however, NOS2 and TGF-${\beta}$ expressed concurrently in left lung after 5 Gy and in both lung after 20 Gy of radiation.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.3
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• pp.51-69
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• 2014

Objectives This study was aimed to investigate the effects of Sibjeondaebotanggamibang (SJT) on the wound-induced rats. Methods It was observed the effects of anti-oxidation and anti-inflammation by using of lipopolysaccharide (LPS)-treated RAW 264.7 cells. For the observing on SJT anti-oxidation, it needed to mesure the total amount of polyphenol, DPPH scavenging ability, ABTS scavenging ability and the value of ROS production. In order to observe on the anti-inflammation of SJT, it was mesured the value of No and Cytokine (TNF-${\alpha}$, IL-$1{\beta}$, IL-6). It needed to make a scar (around $2{\times}2cm^2$) on the top of the fascia in the back of the rats and then the rats were divided into 4 groups (n=6). Control group was not treated at all, whereas SJ group was orally medicated SJT, Terra group was per-cutaneously applied Terramycin, and SJ+Terra group was both orally medicated SJT and percutaneously applied Terramycin per day for three weeks. The size of wound was measured with Digimatic Caliper and the blood samples (WBC, neutrophil, monocyte, lymphocyte) were analyzed using Minos-ST, which were collected by cardiac puncture. The effect on inflammatory cytokine (TNF-${\alpha}$, IL-$1{\beta}$, IL-6), immunological cells in synovial fluid was measured. To measure the wound factor expressed by wounded skin sample, we extracted RNA and to investigate MMP-1,2,9 we used RT-PCR. For performing histopathological examinations, we paralyzed the rats by ether, and extracted wounded skin tissues, which were measured by H & E, and monitored on the optical microscope. Results 1. DPPH and ABTS scavenging activity of SJT was increased concentration-dependantly, and ROS scavenging activity was significantly increased (10, $100{\mu}g/ml$). 2. NO production was significantly reduced in SJT treated cells ($100{\mu}g/ml$), both TNF-${\alpha}$ and IL-6 in SJT treated cells (1, 10, $100{\mu}g/ml$), and IL-$1{\beta}$ in SJT treated cells (1, $100{\mu}g/ml$). 1. The size of wound was significantly decreasing in SJ group, Terra group, SJ+Terra group. 2. WBC was significantly reduced in SJ and SJ+Terra group, monocyte in SJ+Terra group. Neutrophil was also reduced in SJ, SJ+Terra group but meaningless. 3. TNF-${\alpha}$ and IL-6 were significantly reduced in SJ group, Terra group, SJ+Terra group, and IL-$1{\beta}$ in SJ+Terra group. 4. mRNA expression in MMP-1 was significantly reduced in SJ group. 5. Collegan production and chronic inflammation were significantly decreased in SJ group, Terra group, SJ+Terra groups. Re-epithelization on the skin in Terra group, SJ+Terra groups was decreased. Conclusions According to this in vitro experiment, Sibjeondaebotanggamibang (SJT) has the effects of anti-oxidative and anti-inflammatory. By in vivo experiment, SJT has the effects of anti-inflammatory. Moreover, the progress of recovery was found visually, heamatologically, genetically and histopathologically. In conclusion, it could be thought that SJT has effect on the treating of wound.

• Tuberculosis and Respiratory Diseases
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• v.67 no.2
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• pp.95-104
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• 2009

Background: The pathophysiologic mechanisms of early acute lung injury (ALI) differ according to the type of primary insult. It is important to differentiate between direct and indirect pathophysiologic pathways, and this may influence the approach to treatment strategies. NF-$\kappa$B decoy oligodeoxynucleotide (ODN) is a useful tool for the blockade of the expression of NF-$\kappa$B-dependent proinflammatory mediators and has been reported to be effective in indirect ALI. The purpose of this study was to investigate the effect of NF-$\kappa$B decoy ODN in the lipopolysaccharide (LPS)-induced direct ALI model. Methods: Five-week-old specific pathogen-free male BALB/c mice were used for the experiment. In the preliminary studies, tumor necrosis factor (TNF)-$\alpha$, interleukine (IL)-6 and NF-$\kappa$B activity peaked at 6 hours after LPS administration. Myeloperoxidase (MPO) activity and ALI score were highest at 36 and 48 hours, respectively. Therefore, it was decided to measure each parameter at the time of its highest level. The study mice were randomly divided into three experimental groups: (1) control group which was administered 50 ${\mu}L$ of saline and treated with intratracheal administration of 200 ${\mu}L$ DW containing only hemagglutinating virus of Japan (HVJ) vector (n=24); (2) LPS group in which LPS-induced ALI mice were treated with intratracheal administration of 200 ${\mu}L$ DW containing only HVJ vector (n=24); (3) LPS+ODN group in which LPS-induced ALI mice were treated with intratracheal administration of 200 ${\mu}L$ DW containing 160 ${\mu}g$ of NF-$\kappa$B decoy ODN and HVJ vector (n=24). Each group was subdivided into four experimental subgroups: (1) tissue subgroup for histopathological examination for ALI at 48 hours (n=6); (2) 6-hour bronchoalveolar lavage (BAL) subgroup for measurement of TNF-$\alpha$ and IL-6 in BAL fluid (BALF) (n=6); (3) 36-hour BAL subgroup for MPO activity assays in BALF (n=6); and (4) tissue homogenate subgroup for measurement of NF-$\kappa$B activity in lung tissue homogenates at 6 hours (n=6). Results: NF-$\kappa$B decoy ODN treatment significantly decreased NF-$\kappa$B activity in lung tissues. However, it failed to improve the parameters of LPS-induced direct ALI, including the concentrations of tumor necrosis factor-$\alpha$ and interleukin-6 in BALF, myeloperoxidase activity in BALF and histopathologic changes measured by the ALI score. Conclusion: NF-$\kappa$B decoy ODN, which has been proven to be effective in indirect models, had no effect in the direct ALI model.

• Journal of the korean academy of Pediatric Dentistry
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• v.35 no.1
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• pp.47-56
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• 2008

Risperidone is a widely prescribed atypical antipsychotic agent. Approved by the FDA as the first drug to treat irritability associated with autism in children, it is also used to treat tic disorder and Tourette's syndrome. Its adverse reactions related to dentistry include dry mouth, the mechanism of which is yet to be identified. The aim of this study is to identify, at the cellular level, how and to what extent risperidone affects intracellular free calcium concentration ($[Ca^{2+}]_i$), an primary intracellular factor in the regulation of fluid secretion in salivary gland cells. The human salivary gland cell line (HSG) was grown in MEM supplemented with 10% BCS. In order to measure $[Ca^{2+}]_i$, Fura-2/AM was loaded in the HSG, and fluorescence at 340 nm/380 nm excitation was measured in the 500 nm emission ratio. After every experiment, a calibration experiment was conducted in order to readjust the ratio to the actual $[Ca^{2+}]_i$. Changes in $[Ca^{2+}]_i$ were measured in the presence of carbachol, ATP and histamine. The researcher then explored how the pretreatment of risperidone affected such changes. Findings of this study include: 1. In HSG, $[Ca^{2+}]_i$ increased due to the addition of carbachol, ATP and histamine. The presence of risperidone inhibited the action of histamine on this process, while making little effect on that of carbachol and ATP. 2. A quantification of $[Ca^{2+}]_i$ in relation to histamine of different concentrations indicates that the effect of histamine was concentration dependent with an $EC_{50}$ of $3.3{\pm}0.5\;{\mu}M$. 3. The inhibitory effect of risperidone on histamine-induced $[Ca^{2+}]_i$ was concentration-dependent with an $IC_{50}$ of $104.4{\pm}14\;nM$. 4. Risperidone inhibits histamine-induced Ca2+ release from endoplasmic reticulum and influx of extracellular $Ca^{2+}$ in HSG cells(p<0.05).

• Economic and Environmental Geology
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• v.48 no.1
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• pp.51-63
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• 2015

I produced a secular variation model of geomagnetic field by using the magnetic component data from four geomagnetic observatories located in Northeast Asia during the years between 1997 and 2011. The Earth's magnetic field varies with time and location due to the dynamics of fluid outer core and the magnetic observatories on the surface measure in time series. To adequately represent the magnetic field or secular variations of the Earth, a spatio-temporal model is required. In making a global model, satellite observations as well as limited observatory data are necessary to cover the regions and time intervals. However, you need a considerable work and time to process a huge amount of the dataset with complicated signal separation procedures. When you update the model, the same amount of chores is demanded. Besides, the global model might be affected by the measurement errors of each observatory that are biased and the processing errors in satellite data so that the accuracy of the model would be degraded. In this study, as considered these problems, I introduced a localized method in modeling secular variation of the Earth's magnetic field over Northeast Asia region. Secular variation data from three Japanese observatories and one Chinese observatory that are all in the INTERMAGNET are implemented in the model valid between 1997 to 2011 with the interval of 6 months. With the resulting model, I compared with the global model called CHAOS-4, which includes the main, secular variation and secular acceleration models between 1997 to 2013 by using the three satellites' databases and INTERMAGNET observatory data. Also, the geomagnetic 'jerk' which is known as a sudden change in the time derivatives of the main field of the Earth, was discussed from the localized secular acceleration coefficients derived from spline models.

• Progress in Medical Physics
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• v.10 no.1
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• pp.33-40
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• 1999

Purpose: To simulate and measure the signal intensity of various tissues near bone interface in 2D and 3D neurological MR images. Materials and Methods: In neurological proton density (PD) weighted images, every component in the head including cerebrospinal fluid (CSF), muscle and scalp, with the exception of bone, are visualised. It is possible to acquire images in 2D or 3D. A 2D fast spin-echo (FSE) sequence is chosen for the 2D acquisition and a 3D gradient-echo (GE) sequence is chosen for the 3D acquisition. To find out the signal intensities of CSF, muscle and fat (or scalp) for the 2D spin-echo(SE) and 3D gradient-echo (GE) imaging sequences, the theoretical signal intensities for 2D SE and 3D GE were calculated. For the 2D fast spin-echo (FSE) sequence, to produce the PD weighted image, long TR (4000 ms) and short TE$_{eff}$ (22 ms) were employed. For the 3D GE sequence, low flip angle (8$^{\circ}$) with short TR (35 ms) and short TE (3 ms) was used to produce the PD weighted contrast. Results: The 2D FSE sequence has CSF, muscle and scalp with superior image contrast and SNR of 39 - 57 while the 3D GE sequence has CSF, muscle and scalp with broadly similar image contrast and SNR of 26 - 33. SNR in the FSE image were better than those in the GE image and the skull edges appeared very clearly in the FSE image due to the edge enhancement effect in the FSE sequence. Furthermore, the contrast between CSF, muscle and scalp in the 2D FSE image was significantly better than in the 3D GE image, due to the strong signal intensities (or SNR) from CSF, muscle and scalp and enhanced edges of CSF. Conclusion: The signal intensity of various tissues near bone interface in neurological MR images has been simulated and measured. Both the simulation and imaging of the 2D SE and 3D GE sequences have CSF, fat and muscle with broadly similar image intensity and SNR's and have succeeded in getting all tissues about the same signal. However, in the 2D FSE sequence, image contrast between CSF, muscle and scalp was good and SNR was relatively high, imaging time was relatively short.

• Journal of Korea Water Resources Association
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• v.56 no.2
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• pp.103-113
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• 2023

The river confluence is a section in which two rivers with different topographical and hyrodynamic characteristics are combined into one, and it is a section in which rapid flow, inflow of sediments, and hydrological topographic changes occur. In the confluence section, the flow of fluid occurs due to the difference in density due to the type of material or temperature difference, which is called a density flow. It is necessary to accurately measure and observe the confluence section including a certain section of the main stream and tributaries in order to understand the mixing behavior of the water body caused by the density difference. A comprehensive analysis of this water mixture can be obtained by obtaining flow field and flow rate information, but there is a limit to understanding the mixing of water bodies with different physical properties and water quality characteristics of rivers flowing with stratigraphic flow. Therefore, this study attempts to grasp the density flow through the water temperature distribution in the confluence section. Among the extensive data of the river, vertical data and water surface data were acquired, and through this, the stratification phenomenon of the confluence was to be confirmed. It was intended to analyze the mixed pattern of the confluence by analyzing the water mixing pattern according to the water temperature difference using the vertical data obtained by measuring the repair volume by installing the ADCP on the side of the boat and measuring the real-time concentration using YSI. This study can supplement the analysis results of the existing water quality measurement in two dimensions. Based on the comparative analysis, it will be used to investigate the current status of stratified sections in the water layer and identify the mixing characteristics of the downstream section of the river.