단계적 온도 하강법을 이용한 췌도세포 냉동보존법

정인경,오승훈,김병준,양태영,이병완,하창영,노정현,정재훈,민용기,이명식,이문규,김광원 대한당뇨병학회 2002 Diabetes and Metabolism Journal Vol.26 No.1

연구배경:최근 당뇨병의 새로운 치료법으로 시도되고 있는 췌도이식은 충분한 췌도수의 확보와 췌도생존율을 높이기 위한 면역억제제 사용이 제한점이 되고 있다. 본 연구의 목적은 이식 전 충분한 췌도 수의 확보를 위해 분리한 췌도를 냉동보존하는 방법을 확립하고 냉동보존한 백서 췌도세포의 시험관내 그리고 생체내 기능을 조사하였다. 방법:분리한 백서의 췌장소도를 48시간 배양한 후 한 시험관당 췌도세포 1000개씩 나누었다. 냉동보존은 6개의 시험관에 DMSO를 첨가한 후 초 냉각(supercooling), 핵화(nucleation)단계를 거친 후 99% isopropanol과 액체질소가 들어있는 dewer를 이용하여-0.25℃/분의 냉각속도로 -40℃까지 단계적으로 얼린후-70℃ 액체질소 탱크에 보관했다. 해동은 냉동시킨 vial들을 액체 질소 태으에서 꺼내 37℃ 항온조에 담가 급격히 해동시킨 후, 원심분리하여 상층액을 제거하고 각 vial에 0.75M sucrose 용액을 가한 후, 10% fetal calf serum이 함유된 RPMI 1640 media에서 배양하였다 각각 6개의 시험관에서 해동한 췌도들을 광학현미경 및 형광현미경하에서 췌도의 모양과 생존율에 대해 조사하고 인슐린 정적반응을 알아보았다. 또한 분리한 췌도를 냉동보존하지 않고 이식한 경우를 대조군(6마리)과 생체내 기능을 비교하였다. 결과:① 냉동보존후 획득한 췌도의 수와 생존율 해동후 획득한 췌도의 수는 해동시킨 당일날이 902±21, 24시간 배양 후에는 857±16, 72시간 후에는 817±18개로 점차 감소되었다. AO/PI 염색상 각 췌도의 생존율은 냉동 전을 100으로 하였을 때 해동당일, 24시간 후, 72시간 후가 각각 60±5, 80±5, 90±5%로 해동후 3일간 배양하였을 때 냉동전의 수준으로 회복하였다. ② 냉동보존후 췌도의 포도당에 대한 정적 인슐린 분비능:냉동직후 감소된 경향을 보였으나 해동후 3일간 배양한 췌도의 인슐린 분비는 냉동전과 통계적으로 의미있는 차이가 없이 냉동보존 전의 수준으로 회복되었다. ③ 냉동보존후 췌도의 포도당에 대한 동적 인슐린 분비능:냉동보존한 췌도를 해동후 3일째의 인슐린 동적 분비능은 냉동 전과 마찬가지로 자극 인슐린의 반응의 제1기와 2기가 잘 관찰되었다. ④ 냉동보존한 췌도세포 이식 후 혈당 변화:스트렙토조토신으로 유도된 당뇨병 쥐에 췌도이식 후 혈당은 냉동보존한 췌도이식군에서 대조군에 비해 혈당의 조절효과가 더 오래 지속되었다. 결론:소동물에서 단계적 온도 하강법을 이용한 췌도세포 냉동보존법을 확립하였으며 이는 기능, 구조 및 생존율에 큰 이상을 보이지 않았으므로 장차 사람의 췌도세포 동종이식시 부족한 췌도세포수를 극복하고 면역반응을 줄일 수 있는 매우 유용한 방법이 될 것으로 판단된다. Background : Although islet transplantation has been attempted to reverse the state of diabetes, achieving a critical number of islets and modulating the immune response limit the success of islet transplantation. Cryo-preservation of islets offers many important benefits for islet transplantation by collecting islets with a wide variety of HLA phenotypes and islet MHC expression. The aims of this study was to determine the optimal conditions for cryo-preservation by using a controlled cooling method and to evaluate in vitro and in vivo functional properties of the cryo-preserved islets. Methods : Collagenase-isolated, Ficoll-purified islets were cultured for 48 hours. They were aliquoted into freezing tubes (1000 islets per tube), equilibrated with 2M dimethyl sulfoxide (DMSO) in three steps, supercooled, nucleated, and controll-cooled at rate of 0.25℃/min to - 40℃ prior to storage at - 196℃. Rapid thawing and removal of DMSO with 0.75 M sucrose preceded 48 hour of culture and the morphology, viability, glucose-induced insulin secretion, and in vivo function of rats transplanted with cryopreserved islets was reexamined. Results : ① Recovery was 90.2±0.2%, 85.7±0.1% and 81.7±0.1% immendiately after, 24 hours and 72 hours after thawing respectively. The viability was 60±5%, 80±5%, 90±5% immediately after, 24 hours and 72 hours after thawing respectively. ② The glucose-stimulated-insulin secretion (GSIS) tended to decrease immediately after thawing, but GSIS increase to the level of pre-cryopreservation 72 hours after thawing. ③ The in dynamic GSIS, the first and the second phase of insulin secretion were well preserved in islets cultured for 72 hours after thawing. ④ The cryopreserved islets were cultured for 3 days and transplanted into renal sub-capsular space of streptozotocin (STZ) induced diabetic rats. The duration of normoglycemia in the STZ-induced diabetic rats transplanted with cryopreserved islets was significantly longer than of the fresh islets. Conclusion : The optimal condition of cryopreservation using the controlled cooling method was established in rat pancreatic islets. This cryopreservation method can be a feasible approach for human islet transplantation (J Kor Diabetes Asso 26:64~74, 2002).

Electrochemical Studies of Carbon Felt Electrode Modified Under Airless Conditions for Redox Flow Batteries

Noh, Tae Hyoung,Kim, Min Young,Kim, Da Hye,Yang, Seung Hoon,Lee, Jong Ho,Park, Hong Sik,Noh, Hee Sook,Lee, Moo Sung,Kim, Ho Sung The Korean Electrochemical Society 2017 Journal of electrochemical science and technology Vol.8 No.2

Carbon felts were prepared under various thermal conditions to improve the electrochemical properties of vanadium redox flow batteries. The number of C-O and/or C-OH functional groups on the surface of the electrodes treated under airless conditions was much larger than that of the untreated and partially oxygen-treated electrodes. The carbon felt treated under airless conditions had the lowest surface area. The overall kinetic properties of the redox reaction were greatly improved for the carbon felt treated under airless conditions; i.e., the reversibility of the anodic and cathodic reactions associated with the $VO_2{^+}/VO^{2+}$ couple became more reversible. Single-cell tests indicated that the carbon felt exhibited an excellent discharge capacity of $3.1Ah{\cdot}g^{-1}$ at $40mA{\cdot}cm^{-2}$, and the corresponding Coulombic, voltage, and energy efficiencies were 89.5%, 91.8%, and 82.2%, respectively.

Optimal treatment of leptomeningeal spread in glioblastoma: analysis of risk factors and outcome.

Noh, Jung-Hoon,Lee, Min Ho,Kim, Won Seog,Lim, Do Hoon,Kim, Sung Tae,Kong, Doo-Sik,Nam, Do-Hyun,Lee, Jung-Il,Seol, Ho Jun Springer-Verlag 2015 Acta neurochirurgica Vol.157 No.4

<P>Glioblastoma (GBM) is the most common and malignant brain tumor in adults. Despite therapeutic advances, almost all patients eventually experience tumor recurrence. Leptomeningeal spread (LMS) is not a rare condition of recurrence. However, the standard management protocol of LMS has not been established. The aim of this study is to report the risk of (LMS) and the prognosis between treatment modalities in GBM patients.</P>

Optical properties and visible light-induced photocatalytic activity of bismuth sillenites (Bi₁₂XO₂₀, X = Si, Ge, Ti)

Noh, Tae Hoon,Hwang, Sung Won,Kim, Jin Un,Yu, Hak Ki,Seo, Hyungtak,Ahn, Byungmin,Kim, Dong Wook,Cho, In Sun Elsevier 2017 CERAMICS INTERNATIONAL Vol.43 No.15

<P><B>Abstract</B></P> <P>Three bismuth sillenite compounds with the general composition, Bi<SUB>12</SUB>XO<SUB>20</SUB> (X = Si, Ge, Ti), were prepared by a conventional solid state synthesis route and their local crystal structure, light absorption and visible-light induced photocatalytic activities were systematically investigated. The prepared powder samples show comparable particle size distribution (~ 0.5–5µm) and BET surface area (~ 0.8m<SUP>2</SUP>/g). The optical band gap energies were estimated from diffuse reflectance spectra to be in the range 2.6–2.9eV. The local crystal structure variation and its influence on the electronic band structure was elucidated in the three sillenite compounds by Raman analysis and density functional theory (DFT). The visible-light induced photocatalytic activity was evaluated by monitoring the degradation of rhodamine B dye solution under visible-light irradiation (> 420nm). We found that the Bi<SUB>12</SUB>TiO<SUB>20</SUB> powder shows the highest photocatalytic activity, which is attributed to the higher visible light absorption and the smaller band gap resulting from its distinct local crystal structure (longer Bi-O distance).</P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Chest Computed Tomography (CT) Immediately after CT-Guided Transthoracic Needle Aspiration Biopsy as a Predictor of Overt Pneumothorax

( Tae June Noh ),( Chang Hoon Lee ),( Young Ae Kang ),( Sung Youn Kwon ),( Ho Il Yoon ),( Tae Jung Kim ),( Kyung Won Lee ),( Jae Ho Lee ),( Choon Taek Lee ) 대한내과학회 2009 The Korean Journal of Internal Medicine Vol.24 No.4

Background/Aims: This study examined the correlation between pneumothorax detected by immediate posttransthoracic needle aspiration-biopsy (TTNB) chest computed tomography (CT) and overt pneumothorax detected by chest PA, and investigated factors that might influence the correlation. Methods: Adult patients who had undergone CT-guided TTNB for lung lesions from May 2003 to June 2007 at Seoul National University Bundang Hospital were included. Immediate post-TTNB CT and chest PA follow-up at 4 and 16 hours after CT-guided TTNB were performed in 934 patients. Results: Pneumothorax detected by immediate chest CT (CT-pneumothorax) was found in 237 (25%) and overt pneumothorax was detected by chest PA follow-up in 92 (38.8%) of the 237 patients. However, overt pneumothorax was found in 18 (2.6%) of the 697 patients without CT-pneumothorax. The width and depth of CT-pneumothorax were predictive risk factors for overt pneumothorax. Conclusions: CT-pneumothorax is very sensitive for predicting overt pneumothorax, and the width and depth on CT-pneumothorax are reliable risk factors for predicting overt pneumothorax. (Korean J Intern Med 2009;24:343-349)

Enhanced activation of NAD(P)H: quinone oxidoreductase 1 attenuates spontaneous hypertension by improvement of endothelial nitric oxide synthase coupling via tumor suppressor kinase liver kinase B1/adenosine 5&vprime;-monophosphate-activated protein kina

Kim, Yong-Hoon,Hwang, Jung Hwan,Kim, Kyung-Shim,Noh, Jung-Ran,Gang, Gil-Tae,Oh, Won Keun,Jeong, Kyeong-Hoon,Kwak, Tae Hwan,Choi, Hueng-Sik,Lee, In-Kyu,Lee, Chul-Ho Wolters Kluwer Health | Lippincott Williams Wilkin 2014 Journal of Hypertension Vol.32 No.2

AIMS:: Guanosine 5&vprime;-triphosphate cyclohydrolase-1 (GTPCH-1) is a rate-limiting enzyme in de-novo synthesis of tetrahydrobiopterin (BH4), an essential cofactor for endothelial nitric oxide synthase (eNOS) coupling. Adenosine 5&vprime;-monophosphate-activated protein kinase (AMPK) is crucial for GTPCH-1 preservation, and tumor suppressor kinase liver kinase B1 (LKB1), an upstream kinase of AMPK, is activated by NAD-dependent class III histone deacetylase sirtuin 1 (SIRT1)-mediated deacetylation. &bgr;-Lapachone has been shown to increase cellular NAD/NADH ratio via NAD(P)H:quinone oxidoreductase 1 (NQO1) activation. In this study, we have evaluated whether &bgr;-lapachone-induced NQO1 activation modulates blood pressure (BP) through preservation of GTPCH-1 in a hypertensive animal model. METHODS AND RESULTS:: Spontaneously hypertensive rats (SHRs), primary aortic endothelial cells, and endothelial cell line were used to investigate the hypotensive effect of &bgr;-lapachone and its action mechanism. &bgr;-Lapachone treatment dramatically lowered BP and vascular tension in SHRs and induced eNOS activation in endothelial cells. Consistent with these effects, &bgr;-lapachone treatment also elevated levels of both aortic cGMP and plasma nitric oxide in SHRs. Meanwhile, &bgr;-lapachone-treated SHRs showed significantly increased levels of aortic NAD, LKB1 deacetylation, and AMPK Thr phosphorylation followed by increased GTPCH-1 and tetrahydrobiopterin/dihydrobiopterin ratio. In-vitro study revealed that AMPK inhibition by overexpression of dominant-negative AMPK nearly abolished GTPCH-1 protein conservation. Enhanced LKB1 deacetylation and AMPK activation were also elicited by &bgr;-lapachone in endothelial cells. However, inhibition of LKB1 deacetylation by blocking of NQO1 or SIRT1 blunted AMPK activation by &bgr;-lapachone. CONCLUSION:: This is the first study demonstrating that eNOS coupling can be regulated by NQO1 activation via LKB1/AMPK/GTPCH-1 modulation, which is possibly correlated with relieving hypertension. These findings provide strong evidence to suggest that NQO1 might be a new therapeutic target for hypertension.

페라이트/마르텐사이트계 산화물 분산강화 합금의 미세조직과 인장특성에 미치는 Cr, Mo, Al, Zr, Y2O3의 영향

노상훈 ( Sang Hoon Noh ),최지은 ( Ji Eun Choi ),최병권 ( Byoung Kwon Choi ),강석훈 ( Suk Hoon Kang ),김태규 ( Tae Kyu Kim ) 대한금속재료학회(구 대한금속학회) 2014 대한금속·재료학회지 Vol.52 No.9

To develop an advanced ODS alloy for core structural materials for next-generation nuclear reactor system applications, effects of alloying elements such as Cr, Mo, Al, Zr and Y2O3 on microstructures and tensile properties of ODS ferritic/martensitic alloys were investigated. The ODS alloys were fabricated by mechanical alloying, hot isostatic pressing, and hot rolling processes. The Cr concentration revealed little effect on the tensile strength, but it affected the grain morphology as a result of phase transformation. Mo acted to increase the tensile strength at an elevated temperature. Both grain and oxide particle sizes were significantly coarsened by Al addition. These enlargements led to a decrease in tensile strength but improved the elongation. Minor addition of Zr enhanced the tensile strength, and an increase of Y2O3 addition deteriorated the elongation. These results could be very useful in optimizing the alloying element concentration of ODS alloys with superior out-of-pile mechanical properties. (Received July 18, 2013)

Population density of Insect Pests and Natural enemies in the Rice Field

Geon-Hwi Lee,Chae-Hoon Paik,Tae-Hwan Noh,Hyeong-Kwon Shim 한국응용곤충학회 2011 한국응용곤충학회 학술대회논문집 Vol.2011 No.05

Biological control of rice insect pest is an important component of an IPM program. There are many species of natural enemies which contribute to the suppression of rice pest populations below economic injury levels. In order to use biological control more efficiently, it is a need to identify beneficial species and determine their roles in possible regulation of insect pests. There is a rich complex of biological control agents in rice and bund. This research was carried out to investigate the population density of insect pests and natural enemies in the rice field and bund. A total of 7 pest species and 15 natural enemy species were collected in the rice field. 10 pest species and 20 natural enemy species were collected in the bund, also. Changes in population density of insect pests and its prey were investigated in the rice field and bund. Population densities of insect pests were low at any time during the rice growth period in the field. This could be the high density of natural enemies. Bunds served as refuge for natural enemies when rice maturity. There are rich complex of biological control agents in rice field and bund. So, when we practice integrated pest management(IPM) of rice insect pests, we should use various natural enemies.

Occurrence and Developmental Characteristics of Maize Weevil

Geon-Hwi Lee,Chae-Hoon Paik,Tae-Hwan Noh,Hyeong-Kwon Shim 한국응용곤충학회 2011 한국응용곤충학회 학술대회논문집 Vol.2011 No.05

We have gathered rice grain and bran from conventional mills and RPC(Rice Processing Complex) for the survey of stored grain insect pests. Maize weevil(Sittophilus zeamais) is the dominant species among the stored grain insect pests of the rice grain and bran. Under three constant temperatures, 15, 20 and 25℃, developmental periods from egg to adult were 43.0, 37.5 and 29.2 days, respectively. With egg periods being 9.6, 7.3 and 5.2days, and larval periods being 25.2, 21.8 and 19.8days, and adult periods being 126.1, 110.3 and 108.6days, respectively. The adults of Maize weevil feed basically on the same the foods as the larvae but not as restricted in their diets because the larvae need to develop inside whole grains. Feeding of S. zeamais adult usually began 3∼4 days after emergence at 25℃. Then adult feeding ca. one rice a day, reaching a peak of 20∼40days after emergence.

Effect of ethanolamine passivation of ZnO nanoparticles in quantum dot light emitting diode structure

Noh, Kyeongchan,Kim, Minsu,Lee, Sang-Hyun,Yun, Hwang-Sik,Lim, Tae-Hyeon,Choi, Yeongho,Kim, Ki-Ju,Jiang, Yiran,Beom, Keonwon,Kim, Minju,Kim, Young-Gwang,Lee, Pilwoo,Oh, Nuri,Kim, Bong Hoon,Shin, Chansu Elsevier 2019 Current Applied Physics Vol.19 No.9

<P><B>Abstract</B></P> <P>The aging of ZnO nanoparticles in quantum dot light-emitting diode (QD-LED) structures was studied. Coarsening of as-synthesized ZnO nanoparticles is observed in both solution and thin film structures, which potentially deteriorates the performance of QD-LED devices over time. First, the temperature effect on ZnO coarsening was investigated, and it was revealed that aging of ZnO nanoparticles is faster at higher temperature due to a diffusion-controlled mechanism of nanoparticle coarsening. To observe aggregation of ZnO in the film state, the electron transporting part (ZnO/Al) of the QD-LED structure was prepared. The current density of a ZnO film and an electron-only device (QD/ZnO between two electrodes) was also measured. Resistance of the film increased as a function of aging time, which corresponded with observations of the ZnO film by optical microscopy. Aggregation of ZnO nanoparticles was directly measured by the root-mean-square value using atomic force microscopy. Ethanolamine (EA) stabilizer was added to the ZnO solution to disperse the ZnO nanoparticles without aggregation. The effect of EA on the surface passivation of the ZnO found to suppress pinhole formation, as revealed by scanning electron microscopy observations. Finally, the device lifetime was measured for QD-LEDs with EA-stabilized ZnO to understand the effect of ZnO aging on long-term QD-LED device operation.</P>