人蔘이 산소유리기로 손상된 척수신경세포의 손상에 미치는 영향

田炳勳,文炳淳,姜益賢 대한동의병리학회 1998 동의생리병리학회지 Vol.12 No.1

산소자유기는 중풍인 뇌졸중을 비롯하여 뇌허혈, 파킨슨씨병과 같은 뇌질환의 병리적 요인으로 밝혀짐에 따라 이의 독성효과나 작용현상에 대한 기전을 규명하기 위하여 많은 연구가 진행되어 왔다. 그러나 산소자유기의 독성효과에 대하여 아직까지 이에 대한 자세한 기전이 밝혀져 있지 않고 치료방법 역시 미흡한 실정이다. 본 연구는 산소자유기의 신경독성 효과에 대한 기전을 규명하기 위하여 배양소의 희소돌기아교세포에 여러 농도의 산소자유기를 처리한 다음 산소자유기의 독성효과를 측정하였으며 또한 산소자유기의 독성효과에 대한 인삼추출물의 영향을 MTT assay법으로 조사하여 다음과 같은 결론을 얻었다. xanthine oxidase(XO)와 hypoxanthine(HX)은 처리한 농도에 비례하여 배양 신경세포의 생존율을 현저하게 감소시켰으며, 인삼추출물을 배양 희소돌기아교세포에 전처리한 결과 XO/HX의 독성효과를 유의성있게 방어하였다. 이상의 결과로부터 산소자유기는 배양 소의 희소돌기아교세포에 독성을 나타냈으며 인삼추출물이 산소자유기의 독성을 방어하는데 효과적인 것으로 나타났다. To elucidate the neurotoxic mechanism of oxygen radicals in cultured bovine oligodendrocytes, cytotoxic effect was measured by MTT assay after cultured oligodendrocytes were grown in the medium containing various concentrations of oxygen radicals. In addition, neuroprotective effect of herb extract, Korean red Ginseng was examined by MTT assay in cultured oligodendrocytes. Cell viability of cultured oligodendrocytes was remarkably decreased by xanthine oxidase(XO) and hypoxanthine(HX) in dose-dependent manner, and Korean red Ginseng protected remarkably oxidant-induced neurotoxicity in these cultures. From the above results, it is suggested that oxygen radicals is toxic in cultured bovine oligodendrocytes, and herb extracts such as Korean red Ginseng are effective in blocking the neurotoxicity induced by oxygen radicals in cultured bovine oligodendrocytes.

한국프로야구 관중 유인을 위한 야구장 시설의 개선 방안

전익기,유동현 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.6

This research sought to present measures for improving a ballpark facilities to increase the number of spectators of Korean professional baseball matches. To this end, the research surveyed the status and trends of spectators of Korean professional baseball matches, and compared Korean situations with those of the United States and Japan where professional baseball matches are activated. Since its launching in 1982, Korea's professional baseball have been seeing its spectators steadily rising until the figure reached a record high of 5.4 million in 1995, before it plummeted. Korea's professional baseball tournaments reap most of their revenues from admission fees, unlike the United States and Japan. To bolster revenues from admission fees, ballpark facilities need to be expanded and improved. Thus, in consideration of the fact that a rise in spectators leads to an increase in revenues, the research sought to analyze causes of increasing spectators, address current problems surrounding Korea's professional baseball, and thus activate professional baseball matches.

필리핀 여행 후 발생한 쯔쯔가무시병 1예

김계형,김낙현,김문석,김충종,전재현,박완범,장원종,박상원,김익상,오명돈,최강원 대한감염학회 2008 감염과 화학요법 Vol.40 No.6

Infectious diseases imported from other countries have increased as more and more Koreans are going abroad for various purposes. Tsutsugamushi disease from other endemic area such as Southeast Asia is important, because it can occur in any season and eschar may be absent. We report a case of imported tsutsugamushi disease acquired in the Philippines. A patient presented with fever, headache, and maculopapular skin rash. However, eschar was absent. Polymerase chain reaction (PCR) for 56-kDa gene of Orientia tsutsugamushi using buffy coat was positive. Serum indirect immunofluorescent antibody assay was initially negative but became positive with a titer of 1:320 at follow-up, Sequencing analysis revealed the strain to be 100% identical to the TW73R strain identified in Taiwan. After the patient received doxycycline, body temperature normalized in 12 hours. Tsutsugamushi disease is one of the differential diagnoses that should be included for patients with fever who have recently returned from Southeast Asian countries. PCR for O. tsutsugamushi using patient's buffy coat was useful for early diagnosis.

Senescence is accelerated through donor cell specificity in cloned pigs.

Jeon, Hyun Yong,Jeong, Yeon Woo,Kim, Yeon Wook,Jeong, Yeon Ik,Hossein, Shamim M,Yang, Hyun,Hyun, Sang Hwan,Jeung, Eui-Bae,Hwang, Woo Suk D.A. Spandidos 2012 International journal of molecular medicine Vol.30 No.2

<P>Animals cloned by somatic cell nuclear transfer (SCNT) sometimes have abnormalities that result in large offspring syndrome or early death during gestation due to respiratory and metabolic defects. We cloned pigs using two sources of donor cells and observed phenotypic anomalies in three pigs cloned from one type of cell, s-pig fetal fibroblasts. These animals had many wrinkles on their faces and bodies and looked older than age-matched normal pigs. We performed the present study to examine whether the wrinkled phenotype in the cloned pigs was due to senescence, a genetic problem with donor specificity, or epigenetic problems with reprogramming. To address this issue, we investigated biomarkers of senescence, including telomere length and the expression of senescence-associated β-galactosidase (SA-β-gal), glyceraldehyde phosphate dehydrogenase (GAPDH) and β-actin. We also assessed the methylation status of euchromatic PRE-1 repetitive sequences and centromeric satellite DNA, and measured the mRNA levels of six imprinted genes, Copg2, Mest, Igf2R, GNAS, SNRPN and Ube3a. The telomeres of the wrinkled cloned pigs were much shorter than those of the normal cloned pigs and age-matched normal pigs. In the wrinkled cloned pigs, SA-β-gal activity was detected and GAPDH and β-actin were repressed. The mRNA levels of Mest, GNAS and Ube3a were reduced in the wrinkled cloned pigs, although there was no difference between the normal cloned pigs and normal controls. This gene expression analysis indicates that the wrinkled abnormality of our pigs originates from genetic abnormalities in the donor cells used for SCNT.</P>

영농형 태양광 모듈 각도에 따른 일사량 분석

송익현(Ik Hyun Song),손진국(Jin Kug Son),송기오(Ki O Song),조선영(Sun Young Cho),이동규(Dong Kyou Lee),전현익(Hyun Ik Jeon) 한국신재생에너지학회 2018 한국신재생에너지학회 학술대회논문집 Vol.2018 No.11

태권도학과 재학생들의 라이프스타일에 따른 진로의식성숙도에 관한 연구

전익기(Ik-Ki Jeon) · 라정현(Jung-Hyun Ra) 경희대학교 스포츠과학연구원 2008 태권도과학 Vol.1 No.1

This research is conducted by distributing 300 surveys to students that take Taekwondo as a speciality in a full 4 year University in Seoul or in Gyeonggi area. Among the surveys that were distributed 253 were retrieved, and excluding surveys that were useless or had too much error, 218 were used in this analysis. And according to this data we were able to come to these conclusions. First, in order to define the difference in lifestyle and a sense of awareness in course of direction we used an independent T-test and One-Way ANOVA, and in order to prove that there was a noticeable change we used Scheffe's post modern verification and came to find that there was noticeable changes in the lower level of factors of the demographie. Secondly, in order to find the relationship between lifestyle factors and a sense of awareness in course of direction factors we use a Correlation Analysis and found out that there was a high level of correlation. The overall conclusion of this study is that there is a positive and negative relationship between ones personal lifestyle and the lower levels of ones sense of occupation maturity awareness. Thus, since the preference and occupational awareness of each student varies, the Taekwondo departments in colleges should come up with plan to provide the information regarding such work areas in relation to the aptitude test which is taken during admission and should continuously consult with the students so that the students will receive proper courses and reduce the possibility of error during job selection.

Kinetic Study on Aminolysis of Y-Substituted-Phenyl X-Substituted-Benzoates: Effects of Substituents X and Y on Reactivity and Reaction Mechanism

Jeon, Seong Hoon,Kim, Hyun Soo,Han, Young Joon,Kim, Min-Young,Um, Ik-Hwan Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.2

A kinetic study on aminolysis of 2-chloro-4-nitrophenyl X-substituted-benzoates (2a-k) in 80 mol % $H_2O/_20mol%$ DMSO at $25.0^{\circ}C$ is reported. The Br${\emptyset}$nsted-type plot for the reactions of 2-chloro-4-nitrophenyl benzoate (2g) with a series of cyclic secondary amines curves downward (e.g., ${\beta}_1=0.25$, ${\beta}_2=0.85$ and $pK_a^o=10.3$), which is typical of reactions reported to proceed through a stepwise mechanism with a change in ratedetermining step (RDS). The Hammett plot for the reactions of 2a-k with piperidine consists of two intersecting straight lines, while the corresponding Yukawa-Tsuno plot exhibits an excellent linear correlation with ${\rho}_X=1.15$ and r = 0.59. Thus, it has been concluded that the nonlinear Hammett plot is not due to a change in RDS but is caused by stabilization of substrates through resonance interactions between the electron-donating substituent and the C=O bond. Substrates possessing a substituent at the 2-position of the leaving aryloxide deviate negatively from the curved Br${\emptyset}$nsted-type plot for the reactions of Y-substituted-phenyl benzoates (3a-i), implying that the steric hindrance exerted by the substituent at the 2-position is an important factor which governs the reactivity of Y-substituted-phenyl benzoates.

A Study on the Weldability of Cylindrical Secondary Battery Material using Green Laser

Hyun Jong Yoo,Jun Su Park,Ik Geun Jeon,Myung Jin Kim,Jong Sik Kim,Hee Shin Kang 대한용접·접합학회 2024 대한용접·접합학회지 Vol.42 No.1

This study investigates a green laser welding on a nickel-coated copper-mild steel material used in an electric vehicle battery. The laser power and scan speed were varied, and through optical microscopy, it was demonstrated that excessive heat input led to increased weld penetration depth and bead width. Regarding defects, excessive heat input caused the formation of oxide, spatter on the bead surface, as well as porosity and cracks inside the weld penetration depth. The mechanical properties were evaluated through shear stress and microhardness measurements, indicating that as the heat input increased, the mechanical properties improved for the sample welded under the 2 ㎾ condition. Considering the fire risk (occur at weld penetration depth over 50%) and joining aspects (start at weld penetration depth higher 20%), the optimal conditions were set as 1.6 ㎾ and 300 ㎜/s. This optimized condition was set as the reference for monitoring. Based on the optimized condition, the results shown that an increase in heat input led to increased plasma and temperature signals, and an increase in scanning speed resulted in an increase in reflected light signal.

Kinetic Study on Nucleophilic Substitution Reactions of 4-Chloro-2-nitrophenyl X-Substituted-benzoates with Cyclic Secondary Amines: Effect of Substituent X on Reactivity and Reaction Mechanism

Jeon, Seong Hoon,Kim, Hyun Soo,Han, Young Joon,Kim, Min-Young,Um, Ik-Hwan Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.10

Second-order rate constants ($k_N$) have been measured spectrophotometrically for the reactions of 4-chloro-2-nitrophenyl X-substituted-benzoates (1a-1h) with a series of cyclic secondary amines in 80 mol % $H_2O$/20 mol % DMSO at $25.0{\pm}0.1^{\circ}C$. The Hammett plot for the reactions of 1a-1h with piperidine consists of two intersecting straight lines, while the Yukawa-Tsuno plot exhibits an excellent linear correlation with ${\rho}_X $ = 1.25 and r = 0.58, indicating that the nonlinear Hammett plot is not due to a change in the rate-determining step (RDS) but is caused by ground-state stabilization through resonance interactions for substrates possessing an electron-withdrawing group in the benzoyl moiety. The Br${\o}$nsted-type plot for the reactions of 4-chloro-2-nitrophenyl benzoate (1d) with a series of cyclic secondary amines curves downward with ${\beta}_2$ = 0.85, ${\beta}_1$ = 0.24, and $pK_a{^o}$ = 10.5, implying that a change in RDS occurs from the $k_2$ step to the $k_1$ process as the $pK_a$ of the conjugate acid of the amine exceeds 10.5. Dissection of $k_N$ into the microscopic rate constants $k_1$ and $k_2/k_{-1}$ ratio associated with the reaction of 1d reveals that $k_2$ is dependent on the amine basicity, which is contrary to generally held views.

Computer Aided System for Breast Mass Detection and Analysis in Microwave Tomography

Hyun-Ju Choi,Woong-Gi Jeon,Young-Seung Lee,Seong-Ho Son,Hyuk-Je Kim,Soon-Ik Jeon,Heung-Kook Choi 한국멀티미디어학회 2011 한국멀티미디어학회 국제학술대회 Vol.2011 No.-

In this paper, we describe the developing software for breast mass detection and analysis in microwave tomography (MT) as a preliminary study. Our software consists of preprocessing, segmentation, registration, and feature extraction module. In particular, we generated a new template image based on MT to transform individual breast images into a standard anatomical coordinate space. We tested our software on the breast phantom images which were reconstructed from ETRI MT system. The result showed the feasibility of using our software as a computer aided system.