Dietary Calcium and 1,25-Dihydroxyvitamin D₃ Regulate Transcription of Calcium Transporter Genes in Calbindin-D9k Knockout Mice

KO, Sang-Hwan,LEE, Geun-Shik,VO, Thuy T. B.,JUNG, Eui-Man,CHOI, Kyung-Chul,CHEUNG, Ki-Wha,KIM, Jae Wha,PARK, Jong-Gil,OH, Goo Taeg,JEUNG, Eui-Bae Society for Reproduction and Development 2009 Journal of Reproduction and Development Vol.55 No.2

<P>The effect(s) of oral calcium and vitamin D<SUB>3</SUB> were examined on the expression of duodenal and renal active calcium transport genes, i.e., calbindin-D9k (<I>CaBP-9k</I>) and calbindin-D28k (<I>CaBP-28k</I>), transient receptor potential cation channels (<I>TRPV5</I> and <I>TRPV6</I>), Na<SUP>+</SUP>/Ca<SUP>2+</SUP> exchanger 1 (<I>NCX1</I>) and plasma membrane calcium ATPase 1b (<I>PMCA1b</I>), in <I>CaBP-9k</I> KO mice. Wild-type (WT) and KO mice were provided with calcium and vitamin D<SUB>3</SUB>-deficient diets for 10 weeks. The deficient diet significantly decreased body weights compared with the normal diet groups. The serum calcium concentration of the WT mice was decreased by the deficient diet but was unchanged in the KO mice. The deficient diet significantly increased duodenal transcription of <I>CaBP-9k</I> and <I>TRPV6</I> in the WT mice, but no alteration was observed in the KO mice. In the kidney, the deficient diet significantly increased renal transcripts of <I>CaBP-9k</I>, <I>TRPV6</I>, <I>PMCA1b</I>, <I>CaBP-28k</I> and <I>TRPV5</I> in the WT mice but did not alter calcium-relating genes in the KO mice. Two potential mediators of calcium-processing genes, vitamin D receptor (VDR) and parathyroid hormone receptor (PTHR), have been suggested to be useful for elucidating these differential regulations in the calcium-related genes of the KO mice. Expression of VDR was not significantly affected by diet or the KO mutation. Renal <I>PTHR</I> mRNA levels were reduced by the diet, and reduced expression was also seen in the KO mice given the normal diet. Taken together, these results suggest that the active calcium transporting genes in KO mice may have resistance to the deficiency diet of calcium and vitamin D<SUB>3</SUB>.</P>

Changes in Ginsenoside Composition of White Ginseng by Fermentation

Sung Kwon Ko,Ok Sun Cho,Hye Min Bae,Byung Wook Yang,Byung-Ok Im,Young Tae Hahm,Kyung Nam Kim,Soon Hyun Cho,Jae Young Kim,Sung Hyun Chung,Boo Yong Lee 한국식품과학회 2009 Food Science and Biotechnology Vol.18 No.1

The purpose of the study was to develop a new process to manufacture ginseng extract containing saponin aglycon of high concentration. The process to transform saponin glycosides to saponin aglycon was analyzed by high performance liquid chromatography (HPLC). GCK-1 (open cultured mixture for 1 day at 42℃) had the highest content of protopanaxadiol (0.662%). However, other mixtures (GCK-2, 3, 4, 5, and 6) had less than 0.152% in the content of protopanaxadiol. In case of fermentation by inoculation of Bacillus natto, BNG-5 (B. natto inoculated mixture for 5 days at 42℃) showed the highest content of protopanaxadiol (0.364%). Other mixtures (BNG-1, 2, 3, 4, and 6) also showed the high content of more than 0.2% in protopanaxadiol. B. natto inoculation or open culture fermentation with soybean transformed ginseng saponin glycosides into saponin aglycon.

Effect of Matrix Viscosity on Clay Dispersion in Preparation of Polymer/Organoclay Nanocomposites

Ko, Moon-Bae,Jho, Jae-Young,Jo, Won-Ho,Lee, Moo-Sung The Korean Fiber Society 2002 Fibers and polymers Vol.3 No.3

The viscosity effect of matrix polymer on melt exfoliation behavior of an organoclay in poly($\varepsilon$-caprolactone) (PCL) was investigated. The viscosity of matrix polymer was controlled by changing the molecular weight of poly($\varepsilon$-eaprolactone), the processing temperature, and the rotor speed of a mini-molder. Applied shear stress facilitates the diffusion of polymer chains into the gallery of silicate layers by breaking silicate agglomerates down into smaller primary particles. When the viscosity of PCL is lower, silicate agglomerates are not perfectly broken into smaller primary particles. At higher viscosity, all of silicate agglomerates are broken down into primary particles, and finally into smaller nano-scale building blocks. It was also found that the degree of exfoliation of silicate layers is dependent upon not only the viscosity of matrix but thermodynamic variables.

Stimulated Emission with 349-nm Wavelength in GaN/AlGaN MQWs by Optical Pumping

Sung-Bock Kim,Sung-Bum Bae,Young-Ho Ko,Dong Churl Kim,Eun-Soo Nam 한국진공학회(ASCT) 2017 Applied Science and Convergence Technology Vol.26 No.4

The crack-free AlGaN template has been successfully grown by using selective area growth with triangular GaN facet. The triangular GaN stripe structure was obtained by vertical growth rate enhanced mode with low growth temperature of 950℃ and high growth pressure of 500 torr. The lateral growth rate enhanced mode of AlGaN for crackfree and flat surface was also investigated. Low pressure of 30 torr and high V/III ratio of 4400 were favorable for lateral growth of AlGaN. It was confirmed that the 4 μm -thick Al0.2Ga0.8N was crack-free over entire 2-inch wafer. The dislocation density of Al0.2Ga0.8N was as low as ~7.6 × 10<SUP>8</SUP> /cm<SUP>2</SUP> measured by cathodoluminescence. Based on the high quality AlGaN with low dislocation density, the ultraviolet laser diode epitaxy with cladding, waveguide and GaN/AlGaN multiple quantum well (MQW) was grown by metalorganic chemical vapor deposition. The stimulated emission at 349 nm with full width at half maximum of 1.8 nm from the MQW was observed through optical pumping experiment with 193 nm KrF laser. We also have fabricated the deep ridge type ultraviolet laser diode (UV-LD) with 5 μm-wide and 700 μm-long cavity for electrical properties. The turn on voltage was below 5 V and the resistance was ~55 Ω at applied voltage of 10 V. The amplified spontaneous emission spectrum of UV-LD was also observed from pulsed current injection.

Analysis of Ginsenoside Composition of Ginseng Berry and Seed

Sung Kwon Ko,Hye Min Bae,Ok Sun Cho,Byung Ok Im,Sung Hyun Chung,Boo Yong Lee 한국식품과학회 2008 Food Science and Biotechnology Vol.17 No.6

This study was performed to provide basic information that can be used to differentiate Korean ginseng (Panax ginseng C.A. Meyer) berry and seed from American ginseng (Panax quinquefolium L.) seed. Total ginsenoside contents of Korean ginseng berry, Korean ginseng seed, and American ginseng seed were 9.09, 3.30, and 4.06%, respectively. Total ginsenoside content of Korean ginseng berry was about 2.2 to 2.7 times higher than those of Korean ginseng seed and American ginseng seed. Particularly ginsenoside Re content of 4-year cultivated Korean ginseng berry (5.99%) was about 3.6 to 5.4 times higher than that of 4-year cultivated Korean ginseng seed (1.65%) and 4-year cultivated American ginseng seed (1.10%). The contents of total ginsenoside and ginsenoside Re of Korean ginseng berry were about 4.8 and 28 times higher, respectively, than those of 4-year cultivated Korean ginseng root. In general the contents of total ginsenoside and ginsenoside Re of Korean ginseng berry were significantly higher than those of Korean ginseng seed and American ginseng seed.

Quantitative analysis of retained austenite in Nb added Fe-based alloy

Ko Kwang Kyu,Jang Jin Ho,Tiwari Saurabh,Hyo Ju Bae,Sung Hyo Kyung,Kim Jung Gi,설재복 한국현미경학회 2022 Applied microscopy Vol.52 No.1

The use of Pipelines for long-distance transportation of crude oil, natural gas and similar applications is increasing and has pivotal importance in recent times. High specific strength plays a crucial role in improving transport efficiency through increased pressure and improved laying efficiency through reduced diameter and weight of line pipes. TRIP-based high-strength and high-ductility alloys comprise a mixture of ferrite, bainite, and retained austenite that provide excellent mechanical properties such as dimensional stability, fatigue strength, and impact toughness. This study performs microstructure analysis using both Nital etching and LePera etching methods. At the time of Nital etching, it is difficult to distinctly observe second phase. However, using LePera etching conditions it is possible to distinctly measure the M/A phase and ferrite matrix. The fraction measurement was done using OM and SEM images which give similar results for the average volume fraction of the phases. Although it is possible to distinguish the M/A phase from the SEM image of the sample subjected to LePera etching. However, using Nital etching is nearly impossible. Nital etching is good at specific phase analysis than LePera etching when using SEM images.

Antiapoptotic Effect of Paricalcitol in Gentamicin-induced Kidney Injury

Sang Heon Suh,Ko Eun Lee,Jeong Woo Park,In Jin Kim,Ok Kim,Chang Seong Kim,Joon Seok Choi,Eun Hui Bae,Seong Kwon Ma,Jong Un Lee,Soo Wan Kim 대한생리학회-대한약리학회 2013 The Korean Journal of Physiology & Pharmacology Vol.17 No.5

While the anti-apoptotic effect of paricalcitol has been demonstrated in various animal models, it is not yet clear whether paricalcitol attenuates the apoptosis in gentamicin (GM)-induced kidney injury. We investigated the effect of paricalcitol on apoptotic pathways in rat kidneys damaged by GM. Rats were randomly divided into three groups: 1) Control group (n=8), where only vehicle was delivered, 2) GM group (n=10), where rats were treated with GM (150 mg/kg/day) for 7 days, 3) PARI group (n=10), where rats were co-treated with paricalcitol (0.2 Ռg/kg/day) and GM for 7 days. Paricalcitol attenuated renal dysfunction by GM administration in biochemical profiles. In terminal deoxynu-cleotidyl transferase dUTP nick end labeling staining, increased apoptosis was observed in GM group, which was reversed by paricalcitol co-treatment. Immunoblotting using protein samples from rat cortex/outer stripe of outer medulla showed increased Bax/Bcl-2 ratio and cleaved form of caspase-3 in GM group, both of which were reversed by paricalcitol. The phosphorylated Jun-N-terminal kinase (JNK) expression was increase in GM, which was counteracted by paricalcitol. The protein expression of p-Akt and nitro-tyrosine was also enhanced in GM-treated rats compared with control rats, which was reversed by paricalcitol co-treatment. Paricalcitol protects GM-induced renal injury by antiapoptotic mechanisms, including inhibition of intrinsic apoptosis pathway and JNK.

Effect of Various Herbal Extracts on Nitric Oxide Production in Lipopolysaccharide-induced Murine Peritoneal Macrophages

KO, Young Kwon,SEO, Dong Wan,AHN, Seong Hoon,BAE, Gyu Un,YOON,Jong Woo,HONG, Sung Youl,LEE, Hoi Young,HAN, Jeung Whan,LEE, Hyang Woo 성균관대학교 약학연구소 1999 成均藥硏論文集 Vol.11 No.-

Abstract-Nitric oxide (NO) can mediate numerous physiological processes, including vasodilation, neurotransmission, cytotoxicity, secretion and inflammatory response. The regulation of NO production by inducible NO synthase (iNOS) is considered to be the possible target of the development of anti-inflammatory agent, based on the observation that NO can activate cyclooxygenase, which results in the synthesis of prostaglandins. In an effort to screen new inhibitor of NO production from about 352 species of herbal extracts, we found 9species with 50% or more inhibitory effect on NO production. Especially, the dose-dependent inhibition of NO production in lipopolysaccharide-treated macrophages by two of the herbal extracts (Artemisiae asiaticae Herba and Saussureae Radix) was due to the decrease in the expression of iNOS.

Is Aortic Atherothrombotic Disease Detected Using Multidetector-Row CT Associated With an Increased Risk of Early Ischemic Lesion Recurrence After Acute Ischemic Stroke?

Ko, Youngchai,Kim, Wook-Joo,Jang, Myung Suk,Yang, Mi Hwa,Park, Jung Hyun,Choi, Sang Il,Chun, Eun Ju,Lee, Soo Joo,Han, Moon-Ku,Bae, Hee-Joon Ovid Technologies Wolters Kluwer -American Heart A 2012 Stroke Vol.43 No.3

<P>Multidetector-row CT (MDCT) is emerging as a new tool for diagnosing aortic atherothrombotic disease (AAD). We elucidated whether MDCT-detected AAD is associated with an increased risk of early ischemic lesion recurrence on diffusion-weighted MRI after ischemic stroke.</P>

An Approach for Improvement of Goodness of Fit on the Estimation of Paddy Rice Yield Using Satellite(MODIS) Images

Bae-Sung Kim(김배성),Jae-Hwan Kim(김재환),Seong-Bo Ko(고성보) 한국산학기술학회 2013 한국산학기술학회논문지 Vol.14 No.11

본 논문은 MODIS 위성 영상을 이용하여 논벼 생산량을 추정하는 모형의 적합도 개선 및 추정모형내 적 절한 설명변수를 탐색하고자 수행되었다. 또한 이 연구는 한국에서 논벼 생산량 조사를 위해 위성 영상을 사용하 는 방안을 검토하기 위해 수행되었다. 미국, 호주, 일본 등 많은 선진국들은 재배면적 및 생산량 조사와 같은 농업 통계를 산출하기 위해 위성 영상을 이용하고 있다. 그러나 위성 영상을 이용한 작물 생산량 조사의 정확성은 아직 충분치 않은 수준이다. 본 연구는 위성 영상을 이용한 논벼 생산량 조사의 정확도를 증대시키기 위한 몇 가지 방 법을 검토하고 있다. 많은 작물 중 논벼를 연구대상으로 선정한 이유는 논벼가 다른 작물 보다 재배면적과 작황의 영상 분석이 용이하였기 때문이고, 다양한 위성 영상 중 MODIS 영상을 이용한 것은 한국 논벼 생산량 조사 연구 를 위해 보다 적절한 영상을 다수 포함하고 있었기 때문이다. 이 연구에서 등온선에 의해 구분된 논벼로부터 도출 된 NDVI지수, 논벼 등숙기의 일조시간, 강우량, 온도 등 기상변수를 이용하여 단수함수가 추정되었다. 단수함수 추정결과, 모형의 적합도(R-squared)는 0.768-0.891를 보였다. 이 연구는 연평균 등온선에 의해 구분된 NDVI지수와 (등숙기) 기상변수가 단수함수 추정에 매우 유용하게 이용될 수 있음을 보이고 있다. This research was performed in order to improve the goodness of fit of paddy rice production forecasting using MODIS images and to find out appropriate explanatory variables in the forecasting model. The aim of this paper is to review the use of satellite images for the survey of paddy rice production in Korea. Many developed countries, including the United States, Australia, and Japan, have been using satellite images to produce agricultural statistics such as crop production, cultivated acreage, etc. The survey accuracy of crop production by using satellite images, however, is not satisfied in practical use. In this paper, we reviewed several methods to increase the survey accuracy of rice production statistics, gained from satellite images. Rice was selected for this study because its cultivated area and production amount could be more easily identified than other crops by using satellite images. The MODIS images were used because they involved more appropriate images to estimate and analyze rice production. This study estimated yield functions by using the NDVIs, gained from paddy rice yields and annual average isothermal lines, and the meteorological variables such as sunshine hours, rainfall, and temperature during ripening stage. As a result of yield function estimation, the goodness of fit(R-squared) for the models was shown from 0.768 to 0.891. In this study, it is noteworthy academically and practically that vegetation index(NDVIs) identified by annual average isothermal lines and meteorological variables are very useful for estimating yield functions.