• Nuclear Medicine and Molecular Imaging
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• v.41 no.4
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• pp.326-334
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• 2007

Purpose: The estrogen receptor (ER), which is over-expressed in ER-positive breast tumors, has been imaged by positron emission tomography (PET) using $[^{18}F]$ labeled estrogen ligands, especially $[^{18}F]FES$. However, $[^{18}F]$ has relatively short-lived half-life ($t_{1/2}$ =1.8 h) and the labeling yield of radio-fluorination is usually low compared with $^{64}Cu\;(t_{1/2}=12.7\;h)$. 1,4,7,10-tetraazacyclododecane (cyclen) is used to form stable metal complexes with copper, indium, gallium, and gadolinium. With these in mind, we prepared cyclen-based Cu complexes which mimic estradiol in aspect of two hydroxyl groups. Materials and Methods: 1.7-Protected cyclen, 1.7-bis (benzyloxycarbonyl)-cyclen was synthesized according to the reported procedure. After introducing two 4-benzyloxybenzyl groups at 4,10-positions, the benzyloxycarbonyl and benzyl groups were removed at the same time by hydrogenation on Pd/C to give 1,7-bis(4-hydroxybenzyl)-1,4,7,10-tetraazacyclododecane (1). Results: The prepared ligand 1 was fully characterized by $^1H,\;^{13}C$ NMR, and mass spectrometer. The synthesized ligand was reacted with copper chloride and copper perchlorate to give copper complexes $[Cu(1)]^{2+}2(CIO_4^-)\;and\;[Cu(1)Cl]^+Cl^-$ which were confirmed by high-resolution mass (FAB). Conclusion: We successfully synthesized a cyclen derivative of which two phenol groups are located on trans position of N-atoms. And, two Cu(ll) complexes of +2 and +1 overall charge, were prepared as a potential PET tracers for ER imaging.

• KSBB Journal
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• v.15 no.5
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• pp.489-496
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• 2000

Several culture systems including batch, two-stage CSTR, semi-fed batch, and two-stage cyclic fed-batch were investigated for the efficient production of the Fab fraction of PDC-E2 specific human monoclonal antibody using high cell density recombinant E. coli. A two-phase batch system and a two-stage continuous system were examined to overcome plasmid instability problems, by separating the growth and the production stages. The cell density and productivity of the two-stage continuous culture was better than that of the two-phase batch fermentation. In the two-stage continuous culture system with DO-stat, the cell growth and the productivity were superior to those of the system without the DO control. Also, almost total plasmid stability was maintained in the two-stage continuous culture system. Modified M9 medium was selected as an optimum feeding medium for the fed-batch process, and the optimum C/N ratio determined to be 2:3. The optimum feeding rate was $0.6g/\ell/hr$ for a constant feeding strategy in semi-fed batch system. When the feeding medium was fed by pulsing, it was observed that more frequent pulsing resulted in improved cell growth. The linear feeding method was the most efficient of the various feeding methods tested. Finally, high cell density culture using a two-stage cyclic fed batch system with pH-stat was tried because the linear feeding method showed limitations in terms of obtaining high cell densities, and a cell density of $54 g/\ell$ was achieved. It was concluded that the two-stage cyclic fed batch system was the most efficient system for high cell density culture of the systems tested. However, productivity improvements were lower than expected due to the extremely high accumulations of acetate, although the low levels of residual glucose were maintained.

• Preventive Nutrition and Food Science
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• v.6 no.3
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• pp.180-186
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• 2001

Bone marrow cell proliferating arabinogalactan-like polysaccharide (ALR-3IIa-1-1) has been purified from rhizomes of Atractylodes lancea DC. In order to characterize the essential structure of ALR-3IIa-1-1 for expression of the activity, sequential enzymatic digestion using ego-$\alpha$-L-arabinofurasidase (AFase) and ego-$\beta$-D-(1longrightarrow3)-galactanase (GNase) was employed. After ALR-3IIa-1-1 was digested with the AFase, the GNase digestion cleaved only 10% and 23% of 3-linked and 3,6-branched galactose, respectively, from arabinose-trimmed ALR-3IIa-1-1 (AT-ALR-3IIa-1-1), and gave small amounts of intermediate size (AT-G-2) and shorter oligosaccharides (AT-G-3) fractions in addition to a large amount of the GNase resistant fraction (AT-G-1). When AT-G-1 was redigested gradually with the AFase and GNase, it released trace amounts of oligosaccharides in addition to a large amount of the resistant fraction. When the final enzyme-resistant fraction from AT-G-1 was digested simultaneously with both AFase and GNase, the resistant fraction was significantly degraded into two long fragments (3AT-3G-1 and 2). The mixture of digestion products from the first GNase digestion of AT-ALR-3IIa-1-1 showed a significantly decreased bone marrow cell proliferation activity to about 30% of the activity of ALR-3IIa-1-1, but the GNase resistant fraction (AT-7-1) still had significant activity. Although the second gradual enzymatic digestion of AT-G-1 showed a marginal decrease in activity, the resulting fragments (3AT-3G-1 and 2) by the final simultaneous enzymatic digestion lost most of the activity. Component sugar, methylation and FAB-MS analyses indicated that the digestion products (AT-G-21 AT-G-31 2AT-2G-2 and 2AT-2G-3) released from AT-ALR-3IIa-1-1 by the sequential enzymatic digestion contained galactose-containing oligosaccharides mainly comprising 6-linked galactose, that some of which were partially arabinosylated, and these oligosaccharides were attached to $\beta$-D-(1longrightarrow3)-galactan backbone in its non-reducing terminal side as side chains.

• Korean journal of applied entomology
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• v.43 no.2
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• pp.175-180
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• 2004

This study was conducted to determine the effect of sublethal concentrations ($LC_{10}$ and $LC_{30}$) of insecticides on pupal duration, emergence, adult longevity and oviposition of tobacco cutworm, Spodoptera litura Fabricius, when 3rd instar larva of tobacco cutworm was treated with insecticides of chlorpyrifos, ethofenprox, chlorfenapyr-bifenthrin and hexaflumuron-chlorpyrifos . Pupal duration of female and male were 6.9 days and 8.0 days at untreatment, and were 7.2 to 7.6 days and 8.3 to 8.6 days at insecticide treatment, respectively. Thus pupal duration at the insecticide treatment was slightly longer than that at the untreatment, and that of the males was slightly longer than that of the females even though significant difference between sublethal concentrations and among insecticides was not observed. Percent mergence was 88％ at untreatment and ranged from 79％ to 95％, in particular which showed above 91％ treated with chlorfenapyr-bifenthrin and ethofenprox, at insecticide treatment. Adult longevity was 7.7 days and 7.9 days for female and male at untreatment respectively, and 7.1 to 8.4 days for female and 7.7 days to 9.0 days for male at treatment. There was a significant difference between insecticides and sublethal concentrations of insecticides except showed the longest adult longevity at hexaflumuron-chlolfyrifos treatment. Total number of eggs laid were less at treatment (778-948) than that (1,010) at untreatment regardless of sublethal concentrations of insecticides. Accordingly the pupal duration and oviposition of tobacco cutworm were affected at the insecticide treatment of sublethal concentration.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.11
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• pp.5421-5426
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• 2012

A monosomal karyotype (MK), defined as ${\geq}2$ autosomal monosomies or a single monosomy in the presence of additional structural abnormalities, was recently identified as an independent prognostic factor conveying an extremely poor prognosis in patients with acute myeloid leukemia (AML). In the present study, after excluding patients with t(15;17), t(8;21), inv(16) and normal karyotypes, 324 AML patients with cytogenetic abnormalities were the main subject of analysis. The incidences of MK were 13% in patients aged 15 to 60 years and 18% in those between 15 and 88 years old. MK was much more prevalent among elderly patients (p < 0.001) and was significantly associated with the presence of -7, -5, del(5q), abn12p, abn17p, -18 or 18q-, -20 or 20q- and CK (for all p < 0.001 except for abn12p p=0.009), and +8 or +8q was less frequent in MK+ AML(p=0.007). No correlation was noted between monosomal karyotype and FAB subtype (p > 0.05); MK remained significantly associated with worse overall survival among patients with complex karyotype (p=0.032); A single autosomal monosomy contributed an additional negative effect in OS of patients with structural cytogenetic abnormalities (P=0.008). This report presents the prevalence, feature and prognostic impact of MK among a large series of Chinese AML patients from a single center for the first time.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.9
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• pp.4581-4585
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• 2012

Fms-like tyrosine kinase 3 (FLT3) performs a vital role in the pathogenesis of hematopoietic malignancies. Therefore in recent times, the focus of several studies was on use of FLT3 as a prognostic marker. The present study investigated the molecular characterization and incidence of FLT3 mutations in acute leukemia patients in Pakistan. A total of 55 patients were studied, of which 25 were suffering from acute lymphoblastic leukemia (ALL) and 30 were suffering from acute myeloid leukemia (AML). The polymerase chain reaction demonstrated FLT3/ITD mutations in 1 (4%) of 25 ALL patients, a male with the L2 subtype. In AML cases the rate was 4 (13.3%) of 30, three males and one female. The AML-M4 subtype was found in three and the AML M2 subtype in the other. In the AML cases, a statistically significant (p=0.009) relationship was found between WBC (109/L) and FLT3/ITD positivity. However, no significant relationship was found with other clinical parameters (p>0.05). In acute myeloid leukemia (AML) $FLT3/ITD^+$ mutation was more prevalent in elderly patients 31-40 age groups, 21-30 and 51-60 age groups respectively. In acute lymphoblastic leukemia (ALL) statistically no significant relationship was found between clinical features and FLT3/ITD positivity (p>0.05). However, in acute lymphoblastic leukemia (ALL) $FLT3/ITD^+$ mutation was more commonly found in age groups of 21-30.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.425-425
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• 2009

그라핀을 금속 촉매를 이용하여 상압 혹은 저진공 CVD로 성장할 경우 대형 기판을 쉽게 얻을 수 있으므로 최근 들어 금속 촉매를 이용한 CVD 기술이 재 각광받고 있다. 최근 MIT의 Jing Kong 그룹, Purdue 대학의 Yong P. Chen 그룹, 국내에서는 성균관대학에서 이에 대한 논문을 발표한 바 있다. CVD 방법의 가장 큰 장점은 그라핀 박막의 가장 큰 문제점 중 하나인 대형 기판에 매우 유리하다는 점이다. 본 연구에서는 결함 없는 대형 그라핀기판을 얻기위해 Si/$SiO_2$/Ni 박막위에 그라핀을 LPCVD로 성장하는 실험을 진행하였다. 우선 시료는 Si위에 $SiO_2$를 Sputtering으로 증착하였고, 그 위에 250nm, 300nm두께의 Ni 박막을 e-beam evaporator로 증착하였다. $0.5-1cm^2$ 크기의 샘플을 Thermal CVD 장비를 이용하여 그라핀을 성장하는 실험을 진행하였다. 성장 압력은 95 torr, 성장온도는 $800^{\circ}C$, $850^{\circ}C$, $900^{\circ}C$에서 Hydrocarbon ($C_2H_2$)을 5min, 10min으로 성장시간을 split하였다. Hydrocarbon을 흘리기 전에 Ni grain을 성장하기 위해 성장온도에서 30~60min정도 $H_2$분위기에서 Ni 산화막의 환원 및 어닐링을 진행하였다. 그림.1은 $850^{\circ}C$, 5분간 성장한 그라핀/Ni 샘플의 광학사진이다. 그림.2는 $850^{\circ}C$에서 5min, 10min 성장한 샘플의 Raman spectrum이다. (파장은 514.532nm). 850C 10min 샘플은 G>G' peak 이지만, 5min으로 성장한 샘플의 경우 G'>G peak 임을 알 수 있고, 따라서 5min의 조건에서는 층 두께가 4층 미만의 그라핀 박막을 얻을 수 있음을 보여준다. 또한 G' peak의 위치가 두께가 감소할수록 내려감을 확인할 수 있다. 다만 D peak가 실험한 대부분의 샘플에서 보여서 아직 성장한 그라핀의 결합이 많은 것으로 보인다. 이러한 이유는 성장온도가 낮은 것이 일차 원인으로 생각되며 박막의 균일도 향상과 결함을 줄이기 위한 추가적인 개선 실험을 진행 중이다.

• Microbiology and Biotechnology Letters
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• v.26 no.2
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• pp.137-142
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• 1998

Helicobacter pylori is a Gram-negative bacterium which causes chronic gastritis and is associated with gastric ulcer, duodenal ulcer and gastric carcinoma. In the process of screening of antibacterial activities against H. pylori from soil microorganisms, fungus No. 60686 was isolated. After fermentation of No.60686, the antibacterial compound was isolated, purified and followed by extraction of mycelium with organic solvents, acetone and ethyl acetate, through silica gel chromatography, LH-20 gel chromatography and HPLC. As a result of the structural analyses of the compound by IR, $^1$H- and $^{13}$C-NMR, FAB/Mass spectrophotometer, the compound having the antimicrobial activity was identified as chaetoglobosin A ($C_{32}H_{36}N_2O_5$), a cytochalasan derivative. The antimicrobial activity of chaetoglobosin A was tested against Gram-positive and negative bacteria by paper disk method. Among the test strains of 9 Gram-positive bacteria and 18 Gram-negative bacteria containing 4 H. pylori strains, the growth of 4 H. pylori strains and 3 S. aureus strains (SG 511, 285 and 503) was only inhibited by chaetoglobosin A. Also it was shown that its growth inhibition against H. pylori strains was stronger than that against S. aureus strains at the treatment of the same concentration. Therefore it was concluded that chaetoglobosin A has a specific growth inhibition against H. pylori of the tested bacteria.

• Microbiology and Biotechnology Letters
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• v.29 no.2
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• pp.84-89
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• 2001

Isolation and Characterization of Cathepsin B inhibitor Produced by Streptomyces luteogriseus KT-IO. Han, Kil~Hwan and Sang~Dal Kim*. Department of Applied Microbiology, Yeungnam Universit}/t Kyongsan 712749, Korea - The cathepsin B inhibitor produced by Streptomyces luteogriseus KT-IO was very stable in heat, acidic and alkaline conditions. The cathepsin B inhibitor was isolated from the extracted fraction of culture broth with butanol, methanol and chloroform subsequently, the inhibitor was purified with following several column chromatography sLlch as DEAE-Sephadex A-25, Sephadex G-15, silica gel 60, Sephadex LH-20, and preparative HPLC. The cathepsin B inhibitor showed positively to detective reaction of ninhydrine, 5% H2S04, iodine, but negatively to the reaction of Ehrlich's reagent, DNS, aniline. The molecular formular of cathepsin B inhibitor was elucidated by JR, lH and 13C-NMR, FAB mass and elemental analyzer. Consequently, it was identified as C4HlI04N6. The cathepsin B inhibitor had the mode of competitive inhibition with the reaction of cathepsin B.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.244-251
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• 1990

Three viral insecticides were differently formulated with a nuclear polyhedrosis virus isolated from Spdodoptera litura by addition of feeding attractant, anti-precipitate of polyhedra, spreading agent, and UV-protectants. Sucrose was effective for attraction of larval feeding to increase the mortality and for protection of polyhedra from inactivation by sunlight when added 1% to 5% of sucrose solution to the formulations. Contents of additives to the formulations were 0.5% in polyvinyl alcohol to prohibit the precipitation of polyhedra and 0.1% in Triton X-100 to spread and wet the formulations to the plant. Inactivation of the virus under sunlight was decreased when added 800g of white carbon to 100 L of water in the white carbon formulation and 30% of molasses to the molasses's. In the formulation of white carbon and molasses mixtures, activation of the virus was increased when mixtured 500g of the former with 10% of the latter. Three formulations were persisted their pathogenicity more than 95% of mortality at 3 days p.i. Encapsulation of the polyhedral surface was more distinctively coated with the carbon and showed more effective in the residual effects of the white carbon than others, but the molasses more attractive for larval feeding.