• The Korean Journal of Mycology
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• v.25 no.1 s.80
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• pp.26-29
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• 1997

Pyrimidine auxotrophic basidiospores of Pleurotus sajor-caju were selected using positive selection method. Wild type basidiospores could not grow on minimal medium containing the pyrimidine analog 5'-fluoro-orotic acid (5'-FOA) whereas pyrimidine auxotrophs grew normally. After treatment of basidiospores with ultraviolet light, a total of 13 pyrimidine auxotrophic basidiospores were isolated among 24 5'-FOA resistant mutants. These mutants require the pyrimidine such as uracil, cytosine, thymine. Mating type group and growth rate of their mutants were determined.

• Korean Journal of Pharmacognosy
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• v.38 no.3 s.150
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• pp.258-262
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• 2007

In the present study, we investigated the antioxidant activity of methanol extract and its organic fractions (n-hexane, $CH_2Cl_2$, EtOAc, n-BuOH and $H_2O$) of Capsiccum annuum leaves against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. As results, methanol extract, and its ethyl acetate and n-butanol fractions showed good scavenging effect at 100 ${\mu}g/ml$. Four compounds were isolated from the ethyl acetate fraction through silica gel and Sephadex LH-20 column chromatographies. Their chemical structures were elucidated as apigenin (1), vanillic acid (2), uracil (3) and apigenin $7-O-{\beta}-D-apiofuranosyl(1{\rightarrow}2)-{\beta}-D-glucopyranoside$ (4) by comparison of spectral data with those in reference. $IC_{50}$ value of compound 2 was 14.7 ${\mu}g/ml$, while compounds 1, 3 and 4 had no effect on the DPPH radical.

• Journal of Microbiology and Biotechnology
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• v.22 no.11
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• pp.1518-1522
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• 2012

Leuconostoc mesenteroides is a heterofermentative Grampositive bacterium that plays key roles in fermentation of foods such as kimchi, sauerkraut, and milk, leading to the production of various organic acids and aromatic compounds. To study the microbiological and genomic characteristics of L. mesenteroides, we have developed a new chemically defined minimal medium by using the single omission technique. During the exponential cell growth, this species required glutamine, methionine, valine, and nicotinic acid as essential nutrients and 8 amino acids (arginine, cysteine, histidine, leucine, phenylalanine, proline, threonine, and tryptophan), 5 vitamins (ascorbic acid, folic acid, inosine, calcium panthothenate, and thiamine), and others (manganese, magnesium, adenine, uracil, and Tween 80) as supplemental nutrients. This medium is useful to study the metabolic characteristics of L. mesenteroides and to explain its role in food fermentation.

• YAKHAK HOEJI
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• v.38 no.6
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• pp.775-781
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• 1994

$({\pm})-Dioxolane-T$ and$({\pm})-BCH-189$ are know to possess anti-HIV activities, and less to xicities compared to other dideoxynucleoside AIDS drugs. We have synthesized 34 different enantiomerically pure nucleosides by glycosylation of L-1,3-dioxolanyl acetate and L-1,3-oxathiolanyl acetate sugar moieties with uracil or 6-azauracil with alkyl chains$(C_1-C_3)$ on 5 or 6 position.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2004.11a
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• pp.77-85
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• 2004

A significant portion (about 8% in human genome) of mammalian mRNA sequences contains AU(Adenine and Uracil) rich elements or AREs at their 3' untranslated regions (UTR). These mRNA sequences are usually stable. ARE motifs are assorted into three classes. The importance of AREs in biology is that they make certain mRNA unstable. We analyzed the occurrences of AREs and Alu, and propose a possible mechanism on how human mRNA could acquire and keep A REs at its 3' UTR originated from Alu repeats. Interspersed in the human genome, Alu repeats occupy 5% of the 3' UTR of mRNA sequences. Alu has poly-adenine (poly-A) regions at the end that lead to poly -thymine (poly-T) regions at the end of its complementary Alu. It has been discovered that AREs are present at the poly -T regions. In the all ARE's classes, 27-40% of ARE repeats were found in the poly -T region of Alu with mismatch allowed within 10% of ARE's length from the 3' UTRs of the NCBI's reference m RNA sequence database. We report that Alu, which has been reported as a junk DNA element, is a source of AREs. We found that one third of AREs were derived from the poly -T regions of the complementary Alu.

• Radiation Oncology Journal
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• v.30 no.3
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• pp.99-107
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• 2012

Purpose: The aim of this study was to identify clinical predictive factors for tumor response after preoperative chemoradiotherapy (CRT) in rectal cancer. Materials and Methods: The study involved 51 patients who underwent preoperative CRT followed by surgery between January 2005 and February 2012. Radiotherapy was delivered to the whole pelvis at a dose of 45 Gy in 25 fractions, followed by a boost of 5.4 Gy in 3 fractions to the primary tumor with 5 fractions per week. Three different chemotherapy regimens were used (5-fluorouracil and leucovorin, capecitabine, or tegafur/uracil). Tumor responses to preoperative CRT were assessed in terms of tumor downstaging and pathologic complete response (ypCR). Statistical analyses were performed to identify clinical factors associated with pathologic tumor response. Results: Tumor downstaging was observed in 28 patients (54.9%), whereas ypCR was observed in 6 patients (11.8%). Multivariate analysis found that predictors of downstaging was pretreatment relative lymphocyte count (p = 0.023) and that none of clinical factors was significantly associated with ypCR. Conclusion: Pretreatment relative lymphocyte count (%) has a significant impact on the pathologic tumor response (tumor downstaging) after preoperative CRT for locally advanced rectal cancer. Enhancement of lymphocyte-mediated immune reactions may improve the effect of preoperative CRT for rectal cancer.

• The Korean Journal of Nuclear Medicine
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• v.17 no.2
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• pp.71-77
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• 1983

Amino acids such as L-tyrosine, L-histidine, and tryptophan, which bear an aromatic ring in the molecule, could successfully be labelled by radioactive iodine through arylthallium ditrifluoroacetate intermediate. Generally, the labelling reaction could proceed in a short labelling time(ca, 20 minutes) and resulted in a high labelling yields and purity of the labelled product. This procedure has, therefore, been proved to be effective as the labelling method of short labelling time and high specific activity. Labelling proteins such as oval albumin and human albumin could also be achieved in $34\sim48%$ net labelling yield by thallating them at the low temperature $(0\sim10^{\circ}C)$, whereas the labelled products were mainly composed of various denatured products by thallating them at the high temperature$(35\sim40^{\circ}C)$, though the radioactivity was highly retained in the labelled products. Uracil and hippuric acid could also be labelled in a short labelling time though their thallation required a prolonged heating procedure. It was proved that this procedure may be effective to label these compounds by short lived radioisotopes. The labelling yields were, however, lower than 30%.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5127-5131
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• 2013

Background: 5-fluoro-uracil (FU) is a common agent in postoperative chemoradiation in gastric adenocarcinoma. However, FU is not well tolerated in a significant proportion of patients. Capecitabine (CA) is an orally administered fluoropyrimidine carbamate which is preferentially converted to active 5-FU and is one of the agents used instead of FU in such cases. We compared the toxicity, local and distant control and survival rates with FU or oral CA during the course of concurrent radiotherapy to assess the role of CA used instead of FU. Materials and Methods: We conducted an analysis of survival, disease control and toxicity data in 46 patients treated with postoperative chemoradiation following total or subtotal gastrectomy for gastric adenocarcinoma with either FU or CA between January 2008 and December 2012. Results: Median follow-up was 19 months (range: 3-59), median survival time was 23 ({\pm}6.08) months and 1-3 years overall survival (OS) rates were 64.9-39% for all patients. Compared with the CA regimen, the incidence of treatment interruption was higher with FU (p=0.023), but no significant differences were seen in local control (p=0.510), distant recurrences (p=0.721) and survival rates (p=0.866) among patients. Conclusions: Concurrent CA with radiotherapy seems to be a more tolerable and an equally effective regimen for the postoperative treatment of gastric adenocarcinoma when compared to FU.

• Journal of the Korean Chemical Society
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• v.19 no.6
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• pp.438-442
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• 1975

The syntheses of anomeric mixtures of 1-(4-thio-${\alpha},{\beta}$-D-ribofuranosyl)-5-fluoro-and 5-chlorouracils from their corresponding bis(trimethylsilyl) derivatives of 5-halogenouracils and 2,3,5-tri-O-acetyl-4-thio-${\alpha},{\beta}$-D-ribofuranosyl chloride are described. Preliminary biochemical studies showed that in leukemia 1210 cells and Streptococcus faecium, the ${\beta}$-anomeric 5-chloro-4'-thionucleoside is not greatly different from the corresponding 4'-oxygen analog. However, the 5-fluoro-4'-thionucleoside showed a growth inhibitory effect more than that of the oxygen counterpart. The potential chemotherapeutic use of the analog is to warrant further study.

• The Korean Journal of Nuclear Medicine
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• v.30 no.4
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• pp.532-540
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• 1996

목적 : 종양세포의 증식을 평가하기 위해 radiofluorinated ethyluracil (FEU)과 deoxyadenosine analogue(FAD)를 합성하여 종양의 영상화를 시도하였다. 대상 및 방법 : 5-(2-Fluoroethyl)uracil ([$^{18}F$]FEU)은 2, 4-dimethoxy-5-(2-hydroxyethyl) pyrimidine을 $K^{18}F$와 처리한 후 HBr로 가수분해하여 얻었으며 Fluorodeoxyadenosine은 adenosine의 triacetylated analogue를 $K^{18}F$와 처리하여 얻었다. 생물학적 조직분포는 유방암 세포(13762 NF, 100,000 cells per rat, im)를 쥐에 접종한 후 0.5, 1, 2 및 4시간에 주요장기를 적출하여 %ID/g을 측정하고 자가방사영상은 방사성의약품 투여 45분 후에 얻었다. PET 영상은 VX-2 종양을 접종한 가토를 이용하여 얻었다. In vitro cell proliferation assay는 사람의 말초단핵구를 이용하였다. 결 과 : In vitro assay상 ([$^{18}F$]FEU는 세포증식시 DNA/RNA에 결합함을 시사하였다. ([$^{18}F$]FAD와 ([$^{18}F$]FEU의 종양/비종양 방사능 섭취비는 시간경과에 따라 증가하였으며 ([$^{18}F$]FAD와 ([$^{18}F$]FEU를 이용한 자가방사영상과 ([$^{18}F$]FEU를 이용한 PET 영상에서 종양을 잘 관찰할 수 있었다. 결 론 : ([$^{18}F$]FAD 및 ([$^{18}F$]FEU를 이용하여 종양세포의 증식을 PET 영상에서 평가할 수 있으리라 사료된다.