Comparison of trophic factors changes in the hippocampal CA1 region between the young and adult gerbil induced by transient cerebral ischemia.

Yan, Bing Chun,Park, Joon Ha,Kim, Sung Koo,Choi, Jung Hoon,Lee, Choong Hyun,Yoo, Ki-Yeon,Kwon, Young-Geun,Kim, Young-Myeong,Kim, Jong-Dai,Won, Moo-Ho Kluwer Academic/Plenum Publishers 2012 Cellular and molecular neurobiology Vol.32 No.8

<P>In the present study, we investigated neuronal death/damage in the gerbil hippocampal CA1 region (CA1) and compared changes in some trophic factors, such as brain-derived neurotrophic factor (BDNF), glial cell line-derived neurotrophic factor (GDNF) and vascular endothelial growth factor (VEGF), in the CA1 between the adult and young gerbils after 5 min of transient cerebral ischemia. Most of pyramidal neurons (89%) were damaged 4 days after ischemia-reperfusion (I-R) in the adult; however, in the young, about 59% of pyramidal neurons were damaged 7 days after I-R. The immunoreactivity and levels of BDNF and VEGF, not GDNF, in the CA1 of the normal young were lower than those in the normal adult. Four days after I-R in the adult group, the immunoreactivity and levels of BDNF and VEGF were distinctively decreased, and the immunoreactivity and level of GDNF were increased. However, in the young group, all of their immunoreactivities and levels were much higher than those in the normal young group. From 7 days after I-R, all the immunoreactivities and levels were apparently decreased compared to those of the normal adult and young. In brief, we confirmed our recent finding: more delayed and less neuronal death occurred in the young following I-R, and we newly found that the immunoreactivities of trophic factors, such as BDNF, GDNF, and VEGF, in the stratum pyramidale of the CA1 in the young gerbil were much higher than those in the adult gerbil 4 days after transient cerebral ischemia.</P>

AN IN-SITU YOUNG'S MODULUS MEASUREMENT TECHNIQUE FOR NUCLEAR POWER PLANTS USING TIME-FREQUENCY ANALYSIS

Choi, Young-Chul,Yoon, Doo-Byung,Park, Jin-Ho,Kwon, Hyun-Sang Korean Nuclear Society 2009 Nuclear Engineering and Technology Vol.41 No.3

Elastic wave is one of the most useful tools for non-destructive tests in nuclear power plants. Since the elastic properties are indispensable for analyzing the behaviors of elastic waves, they should be predetermined within an acceptable accuracy. Nuclear power plants are exposed to harsh environmental conditions and hence the structures are degraded. It means that the Young's modulus becomes unreliable and in-situ measurement of Young's modulus is required from an engineering point of view. Young's modulus is estimated from the group velocity of propagating waves. Because the flexural wave of a plate is inherently dispersive, the group velocity is not clearly evaluated in temporal signal analysis. In order to overcome such ambiguity in estimation of group velocity, Wigner-Ville distribution as the time-frequency analysis technique was proposed and utilized. To verify the proposed method, experiments for steel and acryl plates were performed with accelerometers. The results show good estimation of the Young's modulus of two plates.

Floristic characteristics of vascular plants and first distributional report of Pseudostellaria baekdusanensis M. Kim in Yongneup wetland protected area

Young-Chul Kim,Hyun-Hee Chae,Sang-Heock Oh,Seung-Ho Choi2,Moon-Pyo Hong3,Gi-Heum Nam,Jae-Yoon Choi,Hyun-Sook Choi,Kyu-Song Lee 한국환경생태학회 2015 한국환경생태학회지 Vol.29 No.2

Yongneup wetland protected area, the only high moor in Korea, is a core area to conserve biodiversity. Even though the Yongneup wetland protected area is relatively small, various plant species are distributed in the Yongneup wetland protected area because it includes various habitats showing different environmental gradients. Vascular plants distributed in the Yongneup wetland protected area were identified as a total of 376 taxa that is composed of 73 families, 217 genera, 322 species, 3 subspecies, 44 varieties and 7 forms. For endangered plants designated by the Ministry of Environment, 5 species including Trientalis europaea var. arctica, Lilium dauricum, Halenia corniculata, Lychnis wilfordii and Menyanthes trifoliata were found and 34 taxa were confirmed to be distributed only in the mountainous wetland habitats. Regarding naturalized plants, a total of 11 taxa were distributed, but most of them were distributed in the areas where artificial interference has occurred. And in areas inside the wetlands that are relatively well preserved, 2 species of Bidens frondosa and Erigeron annuus were observed. In this study, the occurrence and distribution of Pseudostellaria baekdusanensis M. Kim, which was recently found in Mt. Baekdu and reported as a new species, were identified in the Yongneup wetland protected area. A wetland is a very vulnerable area to drastic environmental changes and damages to its ecosystem could cause the extinction of rare plant species which are distributed only in the wetlands. Therefore, it is mandatory that current status of the Yongneup wetland protected area is evaluated and actions to prevent rapid environmental changes are taken. Fourteen separate investigations were conducted in 2013 and another four in 2014, to evaluate current status of the Yongneup wetland protected area. These investigations have provided us the basic information for future actions of conservation and restoration.

영구형 항서맥 심박조율기 환자의 장기추적관찰

최현석,이무용,최영진,최성준,김효수,손대원,오병희,이명묵,박영배,최윤식,이영우,이명용 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.5

위장질환에 따른 H.pylori 감염빈도와 검사방법의 비교분석

김대현,조재현,금민수,최성곤,이창형,탁원형,권영오,김성국,최용환,정준모 慶北大學校 醫科大學 1997 慶北醫大誌 Vol.38 No.2

목적 : H. pylori가 위장관 질환의 병인에 깊은 관련이 있어 이의 적절한 진단 및 치료가 중요하게 대두되고 있다. 이에 저자들은 소화기 증상을 주소로 내원한 환자들을 대상으로 내시경 검사를 실시하여 H. pylori검출을 위한 CLO검사, IgG 항체검사 및 H&E 염색 등을 시행하여 각 질환별로 H. pylori 감염의 양성율을 알아보고 검사법에 따른 민감도 및 특이도를 그 유용성에 대하여 조사하였다. 대상 및 방법 : 1996 4월에서 8월까지 경북대학교병원에 소화기증상을 주소로 내원한 총 313명의 환자를 대상으로 내시경 검사를 실시하여 H. pylori 검출을 위한 CLO 검사, IgG 항체검사, 조직염색 검사를 실시하였다. 결과 : 전체 대상 환자수는 313명이었고 연령별 분포는 16세부터 80세 까지 다양하였으며 그중40대, 50대, 60대가 각각 69예(22%), 73예(23.3%), 65예(20.8%)로 전체 환자중 66%를 차지하였다. 남녀비는 2.07 대 1로 남자가 많았다. 대상환자의 평균나이는 52±15세였고, 전체 대상환자에서 H. pylori 양성군과 음성군의 평균나이는 각각 50±15세, 54±15세 였고, 궤양환자군에서 H. pylori 양성군과 음성군사이의 평균나이는 각각 49±14.8세, 55±13.8세로 나타났다. 각 질환별분포는 위염이 72명(23%), 십이지장 궤양이 85명(27.2%), 위궤양이 80명(25.6%), 위암이 20명(6.4%), 비궤양성 소화불량이 13명(4.2%), 기타가 43명(13.7%)이었으며, H. pylori 감염 양성율은 위염이 71%, 십이지장 궤양이 86.8%, 위궤양이 58.3%, 위암이 75%, 비궤양성 소화불량이 75%였으며 특히 유문륜 궤양에서는 100%의 양성율을 보였다. 소화성 궤양군과 비궤양군에서의 H. pylori 양성율을 비교해 본 결과 궤양군에서는 73.1%, 비궤양군에서는 72%로 통계학적으로 차이는 없었다(P=0.91). 소화성 궤양환자에서 출혈이 동반된 군과 동반되지 않은 군에서의 H. pylori 양성율을 비교해 본 결과 출혈이 동반된 군에서의 양성율은 54.5%였고, 출혈이 동반되지 않은 군에서는 77.5%의 양성율을 보여 출혈이동반되지 않은 군에서 통계학적으로 유의하게 높았다(P=0.014). 나이에 따른 양성율을 알아본 결과 50세 이하에서는 78.5%였고, 50세 이상에서는 67.5%로서 양성율이 낮았으나 통계학적으로 유의성은 없었다(P=0.052). 각 검사법에 따른 민감도 및 특이도는 전체 환자중에서는 CLO검사가 88.9%, 96.1%, IgG항체검사 90.8%, 58.5%, H&E 염색검사 86.9%, 79.2%로서 민감도는 비슷하게 나왔으나 CLO검사는 상대적으로 특이도가 다른 검사법에 비해 높았다. 궤양군에서의 CLO검사의 민감도와 특이도는 92.0%, 95.6%였고, 비궤양군에서의 민감도와 특이도는 84.3%, 96.8%로서 비궤양군에서는 CLO검사의 민감도는 약간 낮았다. 나이에 따른 CLO 검사의 민감도 및 특이도는 50세 이하에서는 91.5%, 93.1% 였고, 50세 이상에서는 86.3%, 97.9%로서 50세 이상에서는 상대적으로 CLO검사의 민감도가 낮았다. 결론 : 본 연구에서는 위장질환에 따른 H. pylori 양성율을 알아보았는데, 다른 보고에서 처럼 높게 나왔으며, 진단 방법으로 사용한 CLO검사, IgG항체 검사, 조직염색검사 등은 모두 비교적 높은 예민도를 나타냈고, 그중 CLO검사가 간편하고 경제적이라는 면에서 임상적으로 유용한 검사로 여겨지나 상대적으로 CLO검사의 민감도가 낮은 비궤양성 질환과 50세 이상의 환자군에서는 CLO검사 외에 다른 검사방법을 병행함으로써 H. pylori의 진단율을 높일 수 있을 것으로 사료된다. Background: Gastric colonization by Helicobacter. pylori is common among patients with peptic ulcer and gastritis. And various diagnostic tests are available in confirming H. pylori infection. The aim of this paper is to estimate the prevalence of H. pylori infection in Gastroduodenal disorders and compare the sensitivity and specificity of the most widely available tests. Methods: A total of 313 patients were tested for H. pylori infection by IgG Ab, CLO test and H&E stains. Results: The prevalence of H. pylori infection was significantly higher in duodenal ulcer(86.8%) than in gastric cancer(75%), gastritis(71%) and gastric ulcer(58.3%)(P=0.009). The sensitivity and specificity of each test was as follows: CLO test(88.9%, 96.1%), IgG Ab test(90.8%, 58.5%), H&E stain(86.9%, 79.2%). Sensitivity of CLO test in peptic group was 92.0%, whereas in non-peptic group, it was 86.3%. Sensitivity of CLO test in age under 50 was 91.5%, that over 50 it was 86.3%. Conculsions: There is a strong association between H. pylori and gastrointestinal disorders. CLO tests have relatively high sensitivity and specificity, especially in peptic group and younger age(below 50 yr)group. But in those patients in which CLO tests are less sensitive (age>50 or non-peptic group), more than one test may be necessary to diagnose the presence of the organism.

PCL-MMT 나노복합재료의 기계적 성질과 생분해에 관한 연구

최현국 ( Hyun-kuk Choi ),이영세 ( Young-sei Lee ),박재경 ( Jae-kyeung Park ) 한국산업융합학회 2005 한국산업융합학회 논문집 Vol.8 No.1

PCL were intercalated into organically modified MMT(PCL-MMT) at 80°C for 4hrs to prepare the PCL-MMT nanocomposite. PCL-MMT and PCL were mixed mechanically with two-roll mill at 150 ℃ for 15mins. From the results of XRD and TEM, it were found that PCL-MMT nanocomposite were prepared. And mechanical properties and biodegradation of nanocomposite have been investigated by tensile meter and biodegradability analysis experiment. Because of MMT dispersed homogeneously in PCL matrix, the Young's modulus of the nanocomposite was found to be excellent. But the tensile strength and elongation were decreased as increase of MMT. And MMT dispersed in PCL matrix was almost not affected on the biodegradation of PCL.

규산질 비료의 참외 흰가루병 발생 억제 효과

류나현,최미영,류연주,조현종,이용세,이영득,정종배 한국환경농학회 2003 한국환경농학회지 Vol.22 No.4

토양에 시용한 규산의 참외 흰가루병에 대한 직접적인 억제 효과와 살균제의 방제 효과를 증진시킬 수 있는 보조효과를 조사하였다. 규산질 비료의 처리는 철가루병 균에 의해 감염된 참외 잎에서 균사의 생장과 분생포자의 형성을 억제함으로써 흰가루병 발생을 일부 억제할 수 있는 것으로 조사되었다. 물론 규산질 비료 자체만의 흰가루병 발생 억제 효과는 매우 미약한 수준이었으나 살균제의 흰가루병 방제 효과를 크게 증진시켜줄 수 있는 것으로 나타났다. 따라서 현재 농가 현장에서 밝혀지고 있는 규산질 비료의 참외 병해 발생 억제 효과는 주로 이러한 살균제의 효과를 증진시킬 수 있는 규산의 보조적인 작용에 기인하는 것으로 판단된다. 따라서 토양에 대한 적절한 수준의 규산질 비료의 시용은 살균제의 방제 효과 증진을 통하여 과다한 약제의 사용과 그에 따른 부작용을 경감시킬 수 있을 것으로 보인다. 규산질 비료의 흰가루병 발생 억제 효과를 증진시키기 위해서는 앞으로 병의 발생을 최대로 억제할 수 있는 참외 잎 중의 적정 규소 함량에 대한 검토 등의 추가적인 연구가 필요할 것이다. Silicon is known to accumulate in plants and results in greater resistance to diseases and insect pests. In this study, we investigated the effect of silicate fertUizer applied in soil on the development of powdery mildew of oriental melon Oriental melon seedlings of four-leaf stage were transplanted and grown in a plastic film house. silicate fertilizer was applied to maintain soil available SiO₂ level of 200 ㎎/㎏ one week before transplanting. Fungicide trinumizol was sprayed three times; one, two, and three weeks after transplanting. Sphaerotheca fuliginea was inoculated 2 weeks after transplanting. The number of infected leaf and the number of fungal colony in leaves were measured one, two, and three weeks after the inoculation. Three weeks after the fungal inoculation, in the treatment of fungicide triflwnhl, infected leaf numbem and number of colony per leaf were reduced by 10 and 58% respectively. In the silicate fertilizer treatment, infected leaf numbers and numbers of colony per infected leaf were suppressed only by 6 and 16%, respectively, and the efficacy was lower than that of the fungicide triflumizol. The combined treatment of silicate fertilizer and the fungicide suppressed powdery mildew more effectively, and infected leaf numbem and numbem of colony per leaf were reduced by 31 and 80%, respectively. These results indicate that although silicate fertilizer itself is not much effective in the suppression of powdery mildew, it can significantly enhance the efficacy of the fungicide.

김치에서 분리한 Lactobacillus sp. JC-7과 Lactobacillus acidophilus 88간의 Electrofusion 최적조건 설정

조영배,최현정,백형석,전홍기 부산대학교 유전공학연구소 1997 분자생물학 연구보 Vol.13 No.-

김치 발효 숙성기간을 연장하고 신선도를 오랫동안 유지 할 수 있는 김치발효 starter의 개발을 목적으로 최적숙성기에 있는 김치로부터 bacteriocin생성능이 없는 유산균을 분리하여 동정하였으며, bacteriocin생성능이 우수한 L.acidophilus 88을 융합시키기 위해 electrofusion에 대한 최적 조건을 검토하였다. 분리균주는 Lactobacillus속으로 동정되어 Lactobacillus sp. JC-7이라 명명하였다. Electrofusion에 의해 생성된 융합주를 식별하기 위해 streptomycin(2.5㎎/ml)에 내성을 나타내는 Lactobacillus sp. JC-7변이주와 kanamycin(600㎍/ml)에 내성을 나타내는 L.acidophilus 88변이주를 분리하였다. Electrofusion을 100V/㎝, 120msec(72ohms,1670 capacitance) 에서 수행했을 때 융합효율이 가장 양호하였으며 전기장의 세기와 시간이 중가할수록 융합 효율이 현저히 감소하였다. 2가 양이온은 농도가 중가할수록 대체적으로 융합효율을 감소시키는 경향을 나타내었으나 1mM MGCl_2에서는 대조군에 비해 융합효율이 약간 증가하였다. PEG매개에 의한 융합법의 융합효율을 비교한 결과, 융합효율은 chemical fusion<electrofusion<electrofusion+20% PEG순을 나타내었다. Evaluation of Optimum Conditions for the Electrofusion between Lactobacillus sp. JC-7 Isolated from Kimchi and Lactobacillus acidophilus 88. Young-Bae Jo, Hyun-Jung Choi, Hyung-Suk Baik and Hong-Ki Jun*. Department of Microbiology, Pusan National University, Pusan 609-735,Korea-A lactic acid bacterium was isolated from kimchi. The isolated strain was identified as the genus Lactobacillus thrugh its morphological characteristics and named as Lactobacillus sp. JC-7. The optimum conditions for the electrofusion between streptomycin(2.5㎎/ml)resistant mutant of Lactobacillus acidophilus 88 and kanamycin(600㎍/ml) resistant mutant Lactobacillus sp. JC-7 were evaluated. The highest number of fusants were obtained at a capacitance value of 120msec(1670㎌), a field strength of 100V/㎝,and a pulse controller setting of 72Ω. The potimum pH of elecroporation buffer was 7.5 and the concentration of divalent cation was 1mM MG^2+. Electrofusants were efficiently obtained by addition 20% polyethylene glycol to electroporation buffer. The yield of fusion was better than that of using polyethylene glycol mediated chemical induction.

데스크탑 밀링머신의 고속 스핀들 설계 해석

장성현,황현영,정우영,홍정표,최영휴 한국공작기계학회 2009 한국공작기계학회 춘계학술대회논문집 Vol.2009 No.-

During a decade, there are many researches on microfactory which is the miniature, flexible, and efficient manufacturing system for the micro/meso scale machining device. Moreover many micro machine tool has developed in Japan, U.S., Europe, and Korea. Already we are developing a desktop milling machine with 380×450×450 ㎣ machine size for microfactory or BT (Bio technology) factory. In this study, we carried out the design analysis of a high speed spindle system for our desktop milling machine by using ADROS, which is our own developed S/W for dynamic design analysis of rotor systems. As the result, we obtained some analyzed dynamic characteristics of a spindle system, such as natural frequency, whirl frequency, critical speed, and harmonic response.

Rat의 복강내에 투여한 5-fluorouracil-polyglycolic acid 제형이 장기에 미치는 영향에 관한 연구

강대영,송규상,최정목,노승무,정경수,오정연,김진향,양준묵,최선웅,이진호,조준식,민병무,김용백,김창식,박근성,김승영,김학용,인현빈 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.1

For more effective intraperitoneal chemotherapy, the authers made 5-fluorouracil-polyglycolic acid composite disks(FU-PGA disks) with 5-fluorouracil and polyglycolic acid, a biodegradable polymer. We inserted the FU-PGA disk into the peritoneal cavites of Sprague-Dawley male rats, the control and three experimental groups; one FU-PGA disk insert group(300mg/kg), two FU-PGA disk insert group(600mg/kg), and three FU-PGA disk insert group(900mg/kg). The control group received a similar number of PGA disk inserts. A pharmacokinetic study was performed to measure the 5-fluorouracil concentration in the peritoneal fluid, blood, and tissues(liver, kidney and heart) at 24 hours, 72hours and 168 hours after insertion of the FU-PGA disk. Light and electron microscopic studies were done. The results were as follows: 1) The number of white blood cells and platelets decreased after FU-PGA insertion. The degree was proportional to the duration and amounts inserted. The change in the number of red blood cells varied slightly. 2) Light microscopically, slight changes were noted at 168 hours in the 3 disk insert group (900mg/kg). Mild fatty change and hepatocyte degeneration around the central veins of the liver were noted, with vacuolar degeneration in the proximal convoluted tubules of the kidney. 3) Electron microscopically,the liver showed focal increases of lipid droplets in the hepatocytes, and irregular nuclear membrane with focal nucleolar segregation of the fibrillar and granular elements. Also the double membranous structure of the hepatocytes and Kupffer cells was widened with bleb formation. The kidney showed wide separation of the nuclear double membrane in the proximal convoluted tubular cells and mesangial cells, with vacuolation and myelin figure formation in the mitochondria of the proximal convoluted tubular cells, at 72 hours and 168 hours in the 2 to 3 FU-PGA insert groups. The heart showed focal loss of cristae,vacuolation and myelin figure formation in the mitochondria of the 2 to 3 FU-PGA insert groups. In conclusion, despite the large amont of FU-PGA inserted, the histopathological changes in the liver, kidney and heart were slight, and consonant with the very low amount of 5-fluorouracil concentrations detected in the liver, kidney and heart. The above results suggest that the FU-PGA composite can serve as a new device for releasing drugs in a controlled manner and easily targeted to intraperitoneal organs. This device can improve the efficacy of intraperitoneal chemotherapy for gastric cancer.