• The Journal of the Korean dental association
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• v.10 no.5
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• pp.307-316
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• 1972

신생 Ball/c Strain 종 웅성백서 28두를 사용하고, 28두중 14두는 실험군에, 나머지 14두는 대조군에 각각 배당하였다. 실험군과 대조군은 동물희생시간(30분, 1시간, 4시간, 8시간, 12시간, 24시간 48시간)에 따라서 7군으로 구분하고, 각군에 2두식 배정하였다. 실험군은 백서를 Bell Jar내에 넣고, 여기에 창소를 서서히 넣어 Westinghouse Oxygen Analyzer로 30내지 40ppm이 되도록 하고 15분 동안 방치한 후, 이를 밖으로 제거하여 신선한 공기를 5분동안 마시게 하였다. 이런 과정을 반복하여 결국 55분 동안에 45분간 무 산소 상태에 있게 하였다. 악하선의 소편을 2% Paraformaldehyde(0.1M Cacodylate fuffer) 용액에 4시간동안 고정하였고, 탈수후 전현 표본포리법에 따라 Epoxy유지를 혼합하여 이몰하였다. LKB Ultratome으로 1μ의 연속절편을 만들었고 야기시킨후 신생백서의 악하선세포에 세포학적변화를 보고저하였고, 기결과를 요약하면 다음과 같다. 1. 신생 백서에 산소결핍을 야기시켰을때에 나타나는 초기의 세포학적변화는 이를 이르킨 후 1시간과 4시간사이가 절정에 달하였다. 이실험에서 유해적 영향은 공포화하고 점액성 및 장액성세포의 핵이 농축변성하며 장액성분필과기의 방출이 지연되어 세포질첨단에 축적되었다. 이들의 회복은 적어도 4시후에 시작되과, 12시간에는 세포질의 대부분, mrgl 핵의 용태가 정상으로 되돌아간다. 24시간에는 실험군과 대조군간에 있어서 야간의 차이는 인정되나 선소엽은 아직 초기에 볼수있었든 퇴행성변화의 잔여물을 함유하고 있었다. 2. 위에 요약한 본연구의 결과는 노인들이 보고한 산소결핍증이 악하선에 있어서도 단백질합성의 억제현상을 나타냈음을 세포학적으로 확증한 것이라하겠다.

• Korean Journal of Pharmacognosy
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• v.53 no.3
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• pp.145-152
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• 2022

Type II diabetes mellitus (T2DM) is a chronic metabolic disease caused by insulin resistance, and abnormally elevated hepatic gluconeogenesis is characterized. Phillyrin, one of the major active constituents of Forsythia suspense, is known to possess the anti-inflammatory and anti-oxidant effects. However, the anti-diabetes mellitus effect of phillyrin and its molecular mechanisms are unclear. The aim of the current study was to investigate the role of phillyrin on gluconeogenesis in insulin resistant HepG2 cells. Phillyrin suppressed high glucose (HG)-induced glucose production. In addition, phillyrin reduced HG-induced the expression of phosphoenolpyruvate carboxykinase (PEPCK) and glucose 6-phosphatase (G6Pase), major genes in hepatic gluconeogenesis. Phillyrin treatment attenuated HG-induced nucleus protein levels of FOXO1 and HDAC5 and increased the phosphorylation of Akt, AMPK, HDAC5, and FOXO1. The block of AMPK and Akt activity did not exert the inhibitory effect of phillyrin on gluconeogenesis in insulin resistant HepG2. Taken together, these results suggest that phillyrin inhibits gluconeogenesis of hepatocytes to improve glucose metabolism, through the regulation of LKB1/AMPK/HDAC5 and PI3K/AKT/FOXO1 pathway. These results indicate that phillyrin may be useful in improving hepatic gluconeogenesis associated with insulin resistant and T2DM.

• Journal of the Korean earth science society
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• v.42 no.5
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• pp.536-555
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• 2021

Sea-surface wind is an important variable in ocean-atmosphere interactions, leading to the changes in ocean surface currents and circulation, mixed layers, and heat flux. With the development of satellite technology, sea-surface winds data retrieved from scatterometer observation data have been used for various purposes. In a complex marine environment such as the Korean Peninsula coast, scatterometer-observed sea-surface wind is an important factor for analyzing ocean and atmospheric phenomena. Therefore, the validation results of wind accuracy can be used for diverse applications. In this study, the sea-surface winds derived from ASCAT (Advanced SCATterometer) mounted on MetOp-A/B (METeorological Operational Satellite-A/B) were validated compared to in-situ wind measurements at 16 marine buoy stations around the Korean Peninsula from January to December 2020. The buoy winds measured at a height of 4-5 m from the sea surface were converted to 10-m neutral winds using the LKB (Liu-Katsaros-Businger) model. The matchup procedure produced 5,544 and 10,051 collocation points for MetOp-A and MetOp-B, respectively. The root mean square errors (RMSE) were 1.36 and 1.28 m s^-1, and bias errors amounted to 0.44 and 0.65 m s^-1 for MetOp-A and MetOp-B, respectively. The wind directions of both scatterometers exhibited negative biases of -8.03° and -6.97° and RMSE values of 32.46° and 36.06° for MetOp-A and MetOp-B, respectively. These errors were likely associated with the stratification and dynamics of the marine-atmospheric boundary layer. In the seas around the Korean Peninsula, the sea-surface winds of the ASCAT tended to be more overestimated than the in-situ wind speeds, particularly at weak wind speeds. In addition, the closer the distance from the coast, the more the amplification of error. The present results could contribute to the development of a prediction model as improved input data and the understanding of air-sea interaction and impact of typhoons in the coastal regions around the Korean Peninsula.

• Applied Microscopy
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• v.20 no.1
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• pp.36-50
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• 1990

This experiment was performed to study the morphological responses of the enterochromaffin cells in the duodenal mucosa of rabbit following bile duct ligation. Adult male rabbits were divided into normal, sham operation and experimental groups. Bile duct ligation was performed under ether anesthesia and animals were sacrificed on the 1st, 3rd, 5th, 7th and 14th day after operation. Mucosal specimens from the duodenum were prefixed with 2.5% glutaraldehyde-1.5% paraformaldehyde(0.1M Millonig's phosphate buffer, pH 7.3), followed by postfixation with 1% osmium tetroxide(0.1M Millonig's phosphate buffer, pH 7.3), and embedded within araldite mixture. The sections were cut on a LKB-V ultratome, and observed under a JEM 100CX II electron miroscope. The results were as follow; 1. Irregularities of the nuclei of the enterochromaffin cells were noticed from the 1st day after bile duct ligation, and concentration of the chromatin in the nucleus was more frequently observed on the 7th and the 14th day. 2. The granular endoplasmic reticulum and Golgi complex of the enterochromaffin cell were more developed than those of the normal on the 1st day after bile duct ligation, but they showed poor organization from the 3rd day. 3. Amount of the microfilaments in the enterochromaffin cell was significantly increased from the 5th day after bile duct ligation and they were more frequently observed in the vicinity of the nucleus. 4. Vacuoles with various electron densities in the enterochromaffin cell were increased in number from the 3rd day after bile duct ligation. 5. Glycogen-like particles in the enterochromaffin cell were frequently observed on the 3rd and the 5th day after bile duct ligation. 6. In the early stage of the ligation of bile duct, in the enterochromaffin cells, well developed intracellular organelles, such as granular endoplasmic reticulum and Golgi apparatus were pronounced. But, in the later stage, the cells contained poor organelles, with the some structural sign of necrotic change.

• Applied Microscopy
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• v.17 no.1
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• pp.83-97
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• 1987

In order to discriminate the enteroendocrine cell types in the mucosal epithelium of the normal duodenum of the Korean hedgehog (Erinaceus koreanus). The tissues were fixed in the mixture of 1% paraformaldehyde and 1% glutaraldehyde in phosphate buffer (pH 7.2), and postfixed in 2% osmium tetroxide (phosphate buffer, pH 7.2). They were embedded in Araldite, and the ultrathin sections were made by LKB-V ultratome following the inspection of semithin sections stained with toluidine blue-borax solutions. Ultrathin sections contrasted with uranyl acetate and lead citrate were observed with JEM 100B electron microscope. At least six types of enteroendocrine cells distributed in the mucosal epithelium of the duodenum were identified according to their morphological characteristics mainly based on the size, shape, number and electron density of the secretory granules. Type I cells had moderately developed organelles. The secretory granules were pleomorphic ($370X510nm$), and the granule cores with high electron density were enveloped in limiting membrane and characterized by a narrow halo. Type II cells contained an indented nucleus and well-developed organelles. The secretory granules were round (350 nm) and classified in two kinds by electron density, moderate and high. Both granules were surrounded by limiting membrane and those with high electron density showed often a wide halo. Type III cells had an indented nucleus. The secretory granules with various electron density were round (220 nm) in shape. The granules with high electron density were enveloped in limiting membrane and characterized by a narrow halo, but those with low or moderate electron density had not been observed the limiting membrane. Type IV cells contained an indented nucleus and moderately developed organelles. The secretory granules were round (180 nm) in shape, and the granule cores with high electron density were enveloped in limiting membrane and showed often a wide halo. Type V cells had a large amount of rough endoplasmic reticulum. Secretory granules with low or moderate electron density were round (230 nm) in shape, and surrounded by limiting membrane and showed a narrow halo. Type VI cells contained an oval nucleus and well-developed organelles, especially Golgi complex. The secretory granules with high electron density were round (210 nm) in shape. The granules were enveloped in limiting membrane and showed often a wide halo.

• Applied Microscopy
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• v.24 no.2
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• pp.63-77
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• 1994

This experiment was performed to study the morphological responses of the epidermis of the rat scalp, following X-ray irradiation. Male rats were divided into normal and experimental groups. Rats anesthetized with sodium thiopental, were exposed only on their head areas with a single dose of 3,000rads or 6,000rads, respectively. Radiation was produced by Mitsubishi Linea Accelerator ML-4MV at the speed of 200rads/min. The target distance was 80cm. Animals were sacrificed on six hours, two days and six days following irradiation. By the perfusion fixation through the heart, rats were fixed with 1% glutaraldehyde-1% paraformaldehyde solution. Pieces of the tissue taken from the scalp were refixed in 2.5% glutaraldehyde-1.5% paraformaldehyde solution, followed by post-fixation with 1% osmium tetroxide, and embedded within araldite mixture. The sections were cut on a LKB-V ultratome, stained with uranyl acetate and lead citrate, and were observed with JEM 100CX-II electron microscope. The results were as follow; 1. Six hours after exposure to 3,000rads of X-ray. Disrupted intercellular spaces, within which some amorphous materials were filled, disrupted mitochondria, and vacuoles in the keratinocytes were frequently observed, but six days after exposure to 3,000rads of X-ray, Morphology of the keratinocytes was generally restored. 2. Many of the morphological changes were seen on the six days after exposure to 6,000rads of X-ray. 3. Widened intercellular spaces and thickened dense plaques of the desmosomes were frequently observed after exposure to 6,000rads of X-ray. 4. In the experimental groups, the Langerhans and the Merkel cells were damaged, similarly to the keratinocyte. Above results suggest that head irradiation with the dose of 3,000rads temporarily damaged the epidermis of the scalp, though most of the structures recover within six days, whereas with the dose of 6,000rads it severely damaged the epidermis without showing any recovering tendency.

• Journal of Radiation Protection and Research
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• v.20 no.2
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• pp.103-115
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• 1995

For the determination of $^{222}Rn$ in water by a very simple and time saving liquid scintillation counting method that does not require any chemical separation, an optimum analytical condition has been investigated. The optimum pulse shape analysis(PSA) level for the measurement of $^{222}Rn$ using LKB 1220 Quantulus liquid scintillation counter was 110 for Optiphase HiSafe3 cocktail and 90 for toluene-based cocktail. The counting efficiencies of $^{222}Rn$ in the window covering u spectra using Optiphase HiSafe3 cocktail were 282.2% for glass vial and 271.6% for Teflon vial, whereas the counting efficiencies in toluene-based cocktail were 262.3% and 247.5% for glass and Teflon vials, respectively. The minimum detectable activity(MDA) in the u window for a 60-min measurement with a Teflon vial using Optiphase HiSafe3 cocktail was $0.30Bq/{\iota}$. The analytical method studied from this work was also applied to the determination of $^{222}Rn$ in some groundwater and hot spring water samples.

• Herbal Formula Science
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• v.24 no.3
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• pp.163-174
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• 2016

Objectives : Rheum undulatum Linne and Glycyrriza uralensis Fischer are widely used herbal medicine. In this study, anti-oxidant and liver protective effects of R. undunlatum extract (RUE) and G. uralensis extract (GUE) were investigated in HepG2 cells, respectively. Oxidative stress and liver fibrosis were induced by arachidonic acid (AA) and iron, and CCl₄.Methods : MTT assay was assessed for cell viability, and immunoblotting analysis was performed to detect expression of apoptosis related proteins. In addition, reactive oxygen species (ROS) and mitochondrial dysfunction were measured. In vivo, BALB/c mouse were orally administrated with the aqueous extract of 10 mg/kg RUE and 100 mg/kg GUE for 3 days and then, injected with CCl₄ 0.5 ml/kg body weight to induce acute liver damage. Serum ALT level was measured, and histological change was observed in Harris's hematoxylin and eosin stainResults : RUE and GUE pre-treatment increased relative cell viability in concentration dependent manner and altered the expression levels of apoptosis-related proteins such as procaspase 3, PARP and Bcl-xL. RUE and GUE also inhibited the mitochondrial dysfunction and excessive reactive oxygen species (ROS) production induced by AA and iron. In addition, RUE and GUE activated liver kinase B1 (LKB1), by increasing phosphorylation. Moreover, RUE and GUE treatment decreased liver injuries induced by CCl₄, as evidenced by decreases in histological liver damage as well as serum alanine amino transferase (ALT) level.Conclusions : These data suggest that RUE and GUE has anti-oxidant and liver protective effects against AA and iron-induced oxidative stress and CCl₄-induced liver injury.

• Analytical Science and Technology
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• v.25 no.2
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• pp.146-151
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• 2012

An analytical method was developed for the measurement of uranium isotope in ground water using the liquid scintillation counting technique. A LKB Wallac Quantulus 1220 liquid scintillation counter (LSC) equipped with pulse shape analyzer (PSA) and a solvent extraction method were used for the measurement of uranium isotope in ground water samples. The effect of solution volume on the extraction efficiency was evaluated for 100 to 1000 mL solutions using a NIST standard reference material (NIST SRM 4321C). The effect of groundwater pH on the extraction efficiency was also investigated for pH ranging from 0.5 to 10. It was found that the extraction efficiency had a strong dependence on pH showing a maximum at pH 2. In contrast, the effect of groundwater volume on the extraction efficiency was negligible in the range investigated. According to the method, the extraction efficiency of uranium isotopes was near 96% and the lower detection limit for uranium was 0.018 Bq/L with the counting time of 300 min. The result of this study was also verified by the conventional ICP-MS measurement. It is demonstrated that the suggested method is valuable to the determination of the optimum extraction and measurement conditions for uranium in ground water. The method was successfully applied to the ground water at four locations near the Daejeon province. It was found that the uranium content and the isotopic ratio of $^{234}U/^{238}U$ at the locations ranged 0.59~6.69 Bq/L and 0.72~1.40, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.5
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• pp.455-460
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• 1991

In order to identify hard distinct 12 fish species(shiba shrimp Metapenaeus joyneri, fleshy shrimp Penaeus orientalis, ridgetail prawn Palaemon carinicauda, yellow croaker Pseudosciaena manchurica, croaker Niber albiflora, Colichthyes fragilis, brown sole Limanda herzensteini, frog flounder Pleuronichthys cornutrs, Areliscus rhomaleus, stone flounder Kareius bicoloratus, harvest fish Pampus argenteus, flag fish Goniistius zonatus) by seeing with naked eye in Kunsan coastal area, sarcoplasmic protein in the supernatant was used for isoelectric focusing. For getting supernatant, fish muscle tissue was blended with two times deionized water and centrifuged (at $4^{\circ}C$, 12,000rpm for 15min). Isoelectric focusing of sarcoploasmic protein carried out on a LKB Multiphor II using polyacrylamide gel plate (2mm thickness, pH $3.5~10^{\circ}C$, pH 5~8 gradient, at $10^{\circ}C$ for 1.5, 3 hours). In case of uncertain protein pattern, pH gradient was modified to narrow pH gradiet, and excuted 2-D electrophoresis using conventional polyacrylamide gel electrophoresis. Most of fishes except yellow croaker and Collichthyes fragilis were distingushed by isoelectric focusing. The protein maps of 2-D electrophoresis for analyzing two protein bands at aimilar positions(pH 5, 6) between the two fish species showed the diffeences of the estimated molecular weights, 11,700(pH5.0) and 87,000(pH6.0)