• Bulletin of the Korean Chemical Society
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• 제25권10호
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• pp.1477-1483
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• 2004

We present the tandem mass spectrometry applications carried out to elucidate the coordination structure of Zn(II) bound lysine ternary complexes, $(Zn+Lys+Lys-H)^+$, which is a good model system to represent a simple (metallo)enzyme-substrate complex (ES). In particular, experimental efforts were focused on revealing the involvement of a lysine side chain ${\varepsilon}$-amino group in the coordination of $Zn^{2+}$ divalent ions. MS/MS fragmentation pattern showed that all the oxygen species within a complex fell off in the form of $H_2O$ in contrast to those of other ternary complexes containing amino acids with simple side chains (4-coordinate geometries, Figure 1a), suggesting that the lysine complexes have different coordination structures from the others. The participation of a lysine basic side chain in the coordination of Zn(II) was experimentally evidenced in MS/MS for $N{\varepsilon}$-Acetyl-L-Lys Zn(II) complexes with acetyl protection groups as well as in MS/MS for the ternary complexes with one $NH_3$ loss, $(Zn+Lys+Lys-NH_3-H)^+$. Detailed structures were predicted using ab initio calculations on $(Zn+Lys+Lys-H)^+$ isomers with 4-, 5-, and 6-coordinate structures. A zwitterionic 4-coordinate complex (Figure 7d) and a 5-coordinate structure with distorted bipyramidal geometry (Figure 7b) are found to be most plausible in terms of energy stability and compatibility with the experimental observations, respectively.

• Journal of Microbiology and Biotechnology
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• 제13권5호
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• pp.717-724
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• 2003

A newly isolated Citrobacter sp. Y19 catalyzes the CO-dependent $H_2$ production (biological water-gas shift reaction) by the actions of CO dehydrogenase (CODH) and hydrogenase. Y 19 requires $O_2$ for fast growth, but its $H_2$ production activity is significantly inhibited by $O_2$. In the present study, the effect of $O_2$ on the activities of CODH ard hydrogenase was investigated quantitatively in both whole cells and broken cells, based on CO-dependent or methyl viologen (MV)-dependent $H_2$ production in addition to CO-dependent MV reduction. In crude cell extracts, CODH activity was mostly found in the soluble fraction. Inactivation of CODH and hydrogenase activities by $O_2$ followed the first-order decay kinetics, and the dependence of the rate constants on $O_2$ partial pressure could be expressed by the Michaelis-Menten equation. In whole cells, the maximum deactivation rate constants ($k_{d,max}$ of hydrogenase and CODH were quite similar: $0.07{\pm}0.03 min^{-1}\;and\;0.10{\pm}0.04 min^{-1}$, respectively. However, the first-order rate constant ($k_{d,max}/K_s$) of CODH ($0.25\;min^{-1}\;atm^{-1}$) at low $O_2$ partial pressures was about 3-fold higher than that of the hydrogenase, since the half-saturation constant ($K_s$) of CODH was about half of that of hydrogenase. In broken cells, both enzymes became significantly more sensitive to $O_2$ compared to the unbroken cells, while $k_{d,max}/K_s$ increased 37-fold for hydrogenase and 6.7-fold for CODH. When whole cells were incubated under anaerobic conditions after being exposed to air for 1 h, hydrogenase activity was recovered more than 90% in 2 h suggesting that the deactivation of hydrogenase by $O_2$ was reversible. On the contrary, CODH activity was not recovered once deactivated by $O_2$ and the only way to recover the activity was to synthesize new CODH. This study indicates that $O_2$ sensitivity of $H_2$ production activity of Citrobacter sp. Y19 is an important drawback as in other $H_2-producing$ bactria.

• 한국수산과학회지
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• 제52권6호
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• pp.725-734
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• 2019

Moon jellyfish Aurelia coerulea are highly abundant off the coast of Tongyeong, Korea. We measured the density of A. coerulea in this area using a scientific echosounder at frequencies of 38 and 120 kHz, and then applied a distorted wave Born approximation (DWBA) model to calculate the target strength of the echosounder at each frequency. Then, we used the frequency difference method to extract jellyfish echo signals and estimate the A. coerulea density. A. coerulea was evenly distributed throughout the water column; the backscattering strength ranged from -75 to -65 dB. In May and August, the A. coerulea densities at survey lines 3 and 4 were estimated at 1.5-1.6 and 0.2-0.9 g/m2, with mean weighted densities of 1.04 and 0.48 g/m2, respectively. In September, the A. coerulea densities estimates in Jaran Bay and Goseong Bay were 0.6-2.1 and 0.1-0.4 g/m2, with mean weighted densities of 1.25 and 0.24 g/m2, respectively.

• International Journal of Oral Biology
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• 제31권2호
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• pp.53-65
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• 2006

Calcium concentration in the bone resorption lacunae is high and is in the mM concentration range. Both osteoblast and osteoclast have calcium sensing receptor in the cell surface, suggesting the regulatory role of high extracellular calcium in bone metabolism. In vitro, high extracellular calcium stimulated osteoclastogenesis in coculture of mouse osteoblasts and bone marrow cells. Therefore we examined the genes that were commonly regulated by both high extracellular calcium and $1,25(OH)_2vitaminD_3(VD3)$ by using mouse oligo 11 K gene chip. In the presence of 10 mM $[Ca^{2+}]e$ or 10 nM VD3, mouse calvarial osteoblasts and bone marrow cells were co-cultured for 4 days when tartrate resistant acid phosphatase-positive multinucleated cells start to appear. Of 11,000 genes examined, the genes commonly regulated both by high extracellular calcium and by VD3 were as follows; 1) the expression of genes which were osteoclast differentiation markers or were associated with osteoclastogenesis were up-regulated both by high extracellular calcium and by VD3; trap, mmp9, car2, ctsk, ckb, atp6b2, tm7sf4, rab7, 2) several chemokine and chemokine receptor genes such as sdf1, scya2, scyb5, scya6, scya8, scya9, and ccr1 were up-regulated both by high extracellular calcium and by VD3, 3) the genes such as mmp1b, mmp3 and c3 which possibly stimulate bone resorption by osteoclast, were commonly up-regulated, 4) the gene such as c1q and msr2 which were related with macrophage function, were commonly down-regulated, 5) the genes which possibly stimulate osteoblast differentiation and/or mineralization of extracellular matrix, were commonly down-regulated; slc8a1, admr, plod2, lox, fosb, 6) the genes which possibly suppress osteoblast differentiation and/or mineralization of extracellular matrix, were commonly up-regulated; s100a4, npr3, mme, 7) the genes such as calponin 1 and tgfbi which possibly suppress osteoblast differentiation and/or mineralization of extracellular matrix, were up-regulated by high extracellular calcium but were down-regulated by VD3. These results suggest that in coculture condition, both high extracellular calcium and VD3 commonly induce osteoclastogenesis but suppress osteoblast differentiation/mineralization by regulating the expression of related genes.

• 마이크로전자및패키징학회지
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• 제25권3호
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• pp.13-19
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• 2018

본 연구에서는 태양광 접속함 모듈 적용을 위한 유연 솔더(Sn-Pb) 및 무연 솔더(Sn-3.0Ag-0.5Cu 및 Sn-1.0Ag-0.7Cu-1.6Bi-0.2In)의 특성을 비교 평가하였다. 접속함 내에는 전압 및 전류 검출용 모듈, 고내압용 다이오드가 실장된 정류모듈 등 다양한 모듈이 내장되어있다. 본 연구에서는 솔더링특성, 인쇄성, 솔더형상 검사, X-ray를 이용한 솔더 내 void 검사 및 접합강도를 측정하였고, 무연 솔더 합금의 공정최적화는 step 1과 step 2로 구분하여 검토를 실시하였다. Step 1은 유연 솔더와 무연 솔더 페이스트 인쇄 검사 시험을 1차와 2차로 나누어 실험을 진행하였고 printability는 void 함량 및 접합강도의 상관관계로 검토하였다. 전체적으로 유연 솔더의 특성은 무연 솔더에 비하여 상대적으로 우수하였다. Step 2는 리플로우 공정의 최고점 온도 변화에 따른 접합부 특성 변화를 관찰하였다. 리플로우 최고 온도가 증가할수록 접합부 내의 void 함량이 2~4% 정도 감소하였고, 접합강도는 약 0.5 kgf 범위내에서 큰 차이 없이 나타났다. 기판 표면처리종류에 있어서는 ENIG 표면처리가 OSP 및 Pb-free 솔더 표면처리보다 우수한 접합강도를 나타내었다. 1종류의 무연솔더와 OSP 표면처리로 접합된 태양광 접속함 모듈의 500 싸이클 열충격 신뢰성시험 전후에 전기적 특성변화는 0.3% 내의 범위에서 안정적으로 작동함을 확인하였다.

• 복식
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• 제39권
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• pp.79-89
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• 1998

This study was carried out the effect of stability and color extract for it's condition in the curcuma L.. dyeing. The stability is to investigate the absorbance of the curcumin, one of the major yellow pigments and the stability regarding the effect of light, oxygen temperature and pH. The dyeing condition is compared the effect of mordanting condition and the best way to extract pigment and analysed through the color-fastness rating, color-difference value test. The main results obtained are summarized as follows ; 1.The best and proper solvent to extrect curcumin pigment was a ethanol and a distilled water. 2. The light effect indicated that the absorbances of solution in absence of ligh was more stable. 3. The oxygen(O2) effect to curcumin show-ed that the condition in the absence of O2 was more stable than that in presence of O2 4. The temperature showed that the absorbnace was best stable in4$^{\circ}C$ and less changed at $25^{\circ}C$ 5. The curcumin-etanol solution was stable in pH 2~4. 6. Generally color-fastness rating to silk, wool and cotton indicated that crocking C.F. and perspiration C.F. were more than 3rd grade and dry cleaning C.F. was more than 4th grade. But light color-fastness and washing color-fastness were very poor. 7. To make good color fastness, the mordan-ting treated group and the pre-mordant conditions were more effective than others 8. When compared with color-difference value test indicated that the silk was looks like more reddish and bluish color and than the wool and cotton were greenish and bluish. As a mordant, A(C2H4OH(COOH3) and D(K2Cr2O7)were more effective to make green-ish color in the silk and the reddish color was abtained by B(Al.K(SO4)2.12H2O) and C(FeSO4.7H2O).

• Radiation Oncology Journal
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• 제33권4호
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• pp.276-283
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• 2015

Purpose: We evaluated the efficacy and toxicity of repeated high dose 3-dimensional conformal radiation therapy (3D-CRT) for patients with unresectable hepatocellular carcinoma. Materials and Methods: Between 1998 and 2011, 45 patients received hepatic re-irradiation with high dose 3D-CRT in Samsung Medical Center. After excluding two ineligible patients, 43 patients were retrospectively reviewed. RT was delivered with palliative or salvage intent, and equivalent dose of 2 Gy fractions for ${\alpha}/{\beta}=10Gy$ ranged from $31.25Gy_{10}$ to $93.75Gy_{10}$ (median, $44Gy_{10}$). Tumor response and toxicity were evaluated based on the modified Response Evaluation Criteria in Solid Tumors criteria and the Common Terminology Criteria for Adverse Events (CTCAE) ver. 4.0. Results: The median follow-up duration was 11.2 months (range, 4.1 to 58.3 months). An objective tumor response rate was 62.8%. The tumor response rates were 81.0% and 45.5% in patients receiving ${\geq}45Gy_{10}$ and $<45Gy_{10}$, respectively (p = 0.016). The median overall survival (OS) of all patients was 11.2 months. The OS was significantly affected by the Child-Pugh class as 14.2 months vs. 6.1 months (Child-Pugh A vs. B, p < 0.001), and modified Union for International Cancer Control (UICC) T stage as 15.6 months vs. 8.3 months (T1-3 vs. T4, p = 0.004), respectively. Grade III toxicities were developed in two patients, both of whom received ${\geq}50Gy_{10}$. Conclusion: Hepatic re-irradiation may be an effective and tolerable treatment for patients who are not eligible for further local treatment modalities, especially in patients with Child-Pugh A and T1-3.

• 핵의학기술
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• 제20권1호
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• pp.37-41
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• 2016

정도관리(Quality Control)는 오차를 최소한으로 하여 검사의 신뢰도를 증진 시키는 것을 목적으로 하고 있으며 이러한 정도관리 활동을 통해 환자의 진단과 치료방침에 영향을 주는 핵의학 혈액 검사의 신뢰도가 확보되고 있다. 이에 연구자들은 신뢰도 향상의 추가적인 기법으로 건강검진 수검자를 대상으로 시행한 핵의학 혈액검사의 모집단 분포를 이용한 통계적 품질관리의 유용성을 평가해 보고자 한다. 2014년 1월부터 2014년 12월까지 서울아산병원 건강증진센터를 이용한 건강검진 수검자 41,341명을 대상으로 핵의학 혈액 검사 12종목에 대해 통계 분석을 시행 하였다. 통계분석은 핵의학 혈액 검사 12종목에 대한 결과 보고 치를 참고치 이내, 참고치 이상, 참고치 이하의 세 가지 그룹의 월간 백분율로 구분하여 모집단 분포의 평균값과 표준편차, 그리고 표준편차 지수(Standard Deviation Index: SDI)를 산출 하였고 그 결과 모집단 분포의 표준편차는 모든 그룹에서 대부분 ${\pm}2SD$ 이내의 결과를 보였다. 건강검진 수검자에 대한 핵의학 혈액검사 12종목(AFP, CEA, CA19-9, CA125, PSA, TSH, FT4, Anti-Tg-Ab, Anti-TPO-Ab, Calcitonin, 25-OH-VitD3, Insulin)의 모집단 분포를 분석한 결과 월간 백분율의 표준편차 지수(SDI)가 ${\pm}2.0$ 이상인 경우는, 1월과 3월 Insulin검사에서 각각 2.3, 2.4, 5월 Anti-Tg-Ab검사에서 2.2, 그리고 9월 CA19-9에서 2.2의 결과를 보였다. 이는 검사 Kit 시약의 이상 (동위원소 시약의 최대 결합률 저하), 검사반응 시간의 저하가 원인 이었다. 연구대상이 되는 전체의 속성을 포함하고 모집단 분포의 특성을 이용한 통계적 품질관리는 검사실에서 시행하고 있는 내부정도관리 프로그램을 보완하는 역할을 할 수 있으리라 생각된다.

• Radiation Oncology Journal
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• 제14권3호
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• pp.191-199
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• 1996

목적 : 자궁경부암에서 근치적 방사선치료후 치료결과 및 예후에 영향을 미치는 인자와 치료후 합병증, 실패 양상을 알고자 후향적 연구를 시행하였다. 대상 및 방법 1986년 3월부터 1990년 5월까지 조직학적 검사로 확진되고 근치적 목적으로 외부조사 및 강내치료를 받은 59명의 환자를 대상으로 후향적 분석을 시행하였다. FIGO 병기에 따른 환자분포는 병기 IIa이하인 Ib, IIa가 각각 2예($3.4\%$), IIb가 31예($52.5\%$), IIIb가 15예 ($25.4\%$), IV가 9예($15.3\%$)였다. 외부조사를 시행한 후, 강내조사를 실시하였는 데, 강내치료는 A점을 기준으로 병기에 따라서 중앙값 3460 cGy(범위: 3000-4366 cGy)까지 조사하였으며, 강내 치료와 외부방사선 치료 전체조사량의 중앙값은 8500 cGy(범위: 8040-10980 cGy)였다. 추적조사 기간은 2개월에서 110개월이었고, 중앙값은 61개월이었다. 결과 : 전체환자의 5년생존율 및 무병생존율은 각각 $55.9\%$와 $55.0\%$였으며, FIGO 병기에 따른 5년 생존율은 병기 IIa이하인 경우 $75.0\%$, 병기 IIb는 $74.8\%$, 병기 IIIb는 $26.7\%$, 병기 IV는 $33.3\%$였다. 단변량 분석에 의하면 병기 IIb이하인 경우 5년 생존율은 $74.8\%$였고, IIIb이상인 경우 $29.2\%$ (p<0.005)였다 방사선치료중 혈색소 수준이 한 번이라도 10 gm/dL미만인 환자군의 5년 생존율은 $0\%$였고, 10 gm/dL이상 군은 $73.3\%$ (p<0.005)였다. 종양의 크기가 5 cm이상인 18예($30.5\%$)에서 5년 생존율은 $22.2\%$였고, 5cm미만인 39예($66.1\%$)에서는 $71.8\%$(p<0.005)였다. 또한 50세이상인 경우와 50세미만인 경우 5년 생존율은 각각 $65.3\%$, $34.2\%$ (p<0.05)였다. ECOG 수행능력 정도, 병리소견, 전체 선량, 전체 치료기간은 통계학적 의미는 없었다. 다변량분석에 의하면 방사선 치료중 혈색소 수준(p=0.0001), 종양의 크기(p=0.0390), FIGO병기 (p=0.0468)가 통계학적 의의를 나타냈다. 전체 환자의 재발율은 $23.7\%$(14/59)로 국소재발이 $15.2\%$(6/59), 원격전이가 $6.8\%$(4/59), 국소재발과 원격전이가 $1.7\%$(1/59)를 보였다. 결장직장과 비뇨생식기에서 각각 $15.3\%$(9/59), $8.5\%$(5/59)를 보이고, Grade 2는 10예($17.0\%$), Grade 3은 3예($5.1\%$), Grade 4도 1예($1.7\%$)를 나타내고 있다 빈도는 방사선 직장염, 직장 출혈, 방사선 대장염, 설사, 방사선 방광염 순서로 발생하였다. 결론 : 치료결과를 향상시키기 위해서는 전향적인 무작위 표본에 의한 새로운 예후인자 발견 및 예후가 좋지 않을 것으로 예상되는 경우, 치료방법의 개선 및 방사선 감작제 또는 항암제를 병용하여 국소재발과 원격전이 억제를 위한 적극적인 치료방법이 연구되어져야 한다고 사료된다.

• 한국수산과학회지
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• 제7권1호
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• pp.1-6
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• 1974

1973년 6월 20일부터 동년 8월 25일까지 사이에 Meretrix lusoria의 성숙난에 $NH_4OH$ 해수용액을 규정농도별로 처리한 후의 인공수정율, 초기발생과정 및 유생의 변태과정을 조사하였다. 1. M. lusoria의 $NH_4OH$ 해수용액 처리에 의한 규정농도별 수정률은 1/1000 N의 $NH_4OH$ 해수용액 처리로 가장 높은 인공수정률을 얻었고, 이렇게 처리된 후 인공수정된 난의 발생과정도 정상적임을 확인하였다. 2. M. lusoria의 초기발생과정에서는 수정후 1시간 35분이 지나면 2할기, 4시간 40분에 포배기, 6시간 15분에 Trochophore기에 달함을 볼 수 있었다. 3. M. lusoria의 유생을 사육한 결과, 수정후 10이 지나면 원각의 평균각장이 $112\mu$인 초기 D형에, 7일이 지나면 평균 각장이 $172\mu$인 각정기에, 20일이 지나면 평균 각장이 $232\mu$인 초기저서기에 달함을 볼 수 있었다. 4. M. luroria의 유생을 실험실내 수조 속에서 사육하며 각장 $272\mu$인 치패을 얻을 수 있었다. 5. M. luroria의 초기 D형기로 부터 변태기까지의 각장(L)과 각고(H)와의 관계는 H=1.02325L-24.46425(상관계수 r=0.99050)의 식으로 표시되었다.