• Biomolecules & Therapeutics
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• 제1권2호
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• pp.244-250
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• 1993

Hematotoxicity and vascular irritation of DA-125, a new anthracycline antitumor antibiotic, were investigated in mice and rabbits. In hematotoxicity study, healthy male ICR mice were treated with DA-125 by a single intravenous injection at doses of 18 and 24 mg/kg. After 4, 8, 12 and 16 days WBC count, RBC count, hemoglobin concentration, hematocrit value, and platelet counts were measured respectively. As a positive control, 12 mg/kg of doxorubicin (DXR) was used in the same manner. Remakable reductions of WBC counts in groups treated with DA-125 or DXR were observed 4 days after administration and returned to normal range 8 days after injection in groups of DA-125 18 mg/kg and DXR 12 mg/kg. The recovery of leukopenia induced in a group of DA-125 24 mg/kg took about 16 days after administration. The RBC counts, hemoglobin concentrations and hematocrit values also decreased in all drug treated groups on day 8 and recovered thereafter. The platelet counts of groups treated with DA-125 or DXR decreased on day 4 and recovered from day 8 of experiment. Local vascular irritation of DA-125 was also assessed in rabbits. The obtained results can be summarized as follows. 1. Thrombophlebitis was not induced even after daily intravenous administration of 0.4% solution of DA-125 or 0.2% solution of DXR for 7 days. 2. Macro- and microscopic observations revealed that the irritative activity of 0.4% solution of DA-125 in blood vessels was not so much different from that of saline when they were injected once a day into vein retroauricularis of rabbits for 7 days. 3. Mild inflammatory reaction was noted around vessels in rabbits treated with 0.2% solution of DXR after consecutive intravenous infusion for more than 5 days. 4. The potencies of vascular irritation of the test solutions were summarized in the following order; saline = 0.4% DA-125<0.2% DXR. These results indicated that DA-125 showed similar pattern of hematotoxicity with DXR but was less hematotoxic than DXR, and that 0.4% solution of DA-125 did not elicit unusual toxic properties when injected through intravenous route for clinical practice.

• Biomolecules & Therapeutics
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• 제1권1호
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• pp.9-19
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• 1993

DA-125, a new anthracycline antibiotic, showed antitumor activity against animal tumors and human tumors. Therefore we studied the cardiotoxic potential of DA-125 in hamsters and rats as a part of safety research, and compared it with that of doxorubicin(DXR). In acute cardiotoxicity test model used hamsters DA-125 was administered intravenously at a dose of 6, 9, 12 mg/kg, and DXR at 3 mg/kg was given. The electrocardiogram(ECG) of hamsters was recorded for 30 minutes after administration. The DA-125 caused slight ECG alterations at a dose of 6 mg/kg. At a dose of 12 mg/kg DA-125 induced moderate to remarkable changes in ECG like decrease of heart rate, widening of PR interval and 07 interval, and A-V block in 3 out of 5 animals. The severity of ECG alteration at 12 mg/kg of DA-125 was similar to that at 3mg/kg of DXR and these changes caused by DA-125 and DXR recovered within 10 minutes after injection. In chronic cardiotoxicity test model used rats, DA-125 was administered intravenously once a week for three weeks at a dose of 6, 9mg/kg and DXR was given at a dose of 6mg/kg. Electrocardiogram was recorded every week from the start of administration to 2 weeks after the last administration and the animals were sacrificed for histological heart examination at 1 week or 2 weeks after the last administration. DA-125 did not cause any abnormal changes in ECG and in histological heart examination due to administration, but DXR caused widening of ST segment, QRS complex, and QT interval from 1 week after administration and these changes were continued to necropsy. These alterations in ECG were accompanied by cardiac histological lesions such as vacuolation in myocardiac cells, interstitial edema and necrosis of myocytes. These results suggest that DA-125 is less cardiotoxic than DXR.

• Korean Journal of Radiology
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• 제22권4호
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• pp.634-651
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• 2021

Dynamic X-ray (DXR) is a functional imaging technique that uses sequential images obtained by a flat-panel detector (FPD). This article aims to describe the mechanism of DXR and the analysis methods used as well as review the clinical evidence for its use. DXR analyzes dynamic changes on the basis of X-ray translucency and can be used for analysis of diaphragmatic kinetics, ventilation, and lung perfusion. It offers many advantages such as a high temporal resolution and flexibility in body positioning. Many clinical studies have reported the feasibility of DXR and its characteristic findings in pulmonary diseases. DXR may serve as an alternative to pulmonary function tests in patients requiring contact inhibition, including patients with suspected or confirmed coronavirus disease 2019 or other infectious diseases. Thus, DXR has a great potential to play an important role in the clinical setting. Further investigations are needed to utilize DXR more effectively and to establish it as a valuable diagnostic tool.

• Clinical and Experimental Pediatrics
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• 제48권12호
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• pp.1378-1384
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• 2005

목 적 : ADR 유발성심근증 생쥐 모델에서 PTX와 DXR의 심근증에 대한 예방 및 치료 효과를 알아보고자 하였다. 방 법 : 생후 6주된 Sprague-Dawley rat를 정상대조군(n=4), 질환대조군(n=6), DXR군(n=5), PTX군(n=6), 병용치료군(n=5)으로 나누고 정상 대조군을 제외한 4군에 ADR(5 mg/kg)을 1주 간격으로 2회 미정맥으로 투여하여 심근증을 유발하였다. DXR군은 매 ADR 투여 30분 전에 DXR(100 mg/kg)을 미정맥으로 주사하였다. PTX군은 3주간 매일 PTX(50 mg/kg/day)을 경구투여하였다. 5군 모두 3주 뒤에 희생시켜 좌심실 조직의 광학현미경적소견을 관찰하여 심근증의 정도를 분석하였다. 면역조직학적 염색을 통해 Bcl-2 발현의 변화를 조사하였고 $TNF-{\alpha}$와 CTGF에 대한 RT-PCR을 시행하였다. 결 과 : 광학현미경 소견상 세포질의 공포형성과 과수축 밴드괴사 그리고 섬유화는 정상대조군에 비해 질환대조군에서 유의하게 증가하였고 병용치료군에서 감소하였다(P<0.01). 심근 섬유화는 PTX군과 병용치료군에서 ADR군에 비해 유의하게 감소하였다. Bcl-2의 발현은 질환대조군에서 낮았으며 DXR군과 병용치료군에서 질환대조군에 비해 Bcl-2의 발현이 증가하여 호전되었다(P<0.05). $TNF-{\alpha}$는 mRNA와 단백질의 발현상 정상대조군과 질환대조군에서 차이가 없었다. 결 론 : ADR 유발성심근증에 DXR과 PTX를 함께 투여하였을 경우 DXR은 bcl-2의 발현을 증가시키고 심근세포의 자멸사를 억제하였고 PTX는 심근 섬유화를 억제하였다. 그리고 ADR과 PTX를 병용 투여하였을 경우 최대의 심근증 예방 효과를 볼 수 있었다.

• ALGAE
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• 제32권4호
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• pp.359-377
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• 2017

Pyropia haitanensis (T. J. Chang et B. F. Zheng) N. Kikuchi et M. Miyata is one of the most commercially useful macroalgae cultivated in southeastern China. In red algae, the biosynthesis of terpenoids through 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway can produce a direct influence on the synthesis of many biologically important metabolites. In this study, two genes of cDNAs, 1-deoxy-D-xylulose-5-phosphate synthase (DXS) and 1-deoxy-D-xylulose-5-phosphate reductase (DXR), which encoding the first two rate-limiting enzymes among MEP pathway were cloned from P. haitanensis. The cDNAs of P. haitanensis DXS (PhDXS) and DXR (PhDXR) both contained complete open reading frames encoding polypeptides of 764 and 426 amino acids residues, separately. The expression analysis showed that PhDXS was significant differently expressed between leafy thallus and conchocelis as PhDXR been non-significant. Additionally, expression of PhDXR and its downstream gene geranylgeranyl diphosphate synthase were both inhibited by fosmidomycin significantly. Meanwhile, we constructed types of phylogenetic trees through different algae and higher plants DXS and DXR encoding amino acid sequences, as a result we found tree clustering consequences basically in line with the "Cavalier-Smith endosymbiotic theory." Whereupon, we speculated that in red algae, there existed only complete MEP pathway to meet needs of terpenoids synthesis for themselves; Terpenoids synthesis of red algae derivatives through mevalonate pathway came from two or more times endosymbiosis of heterotrophic eukaryotic parasitifer. This study demonstrated that PhDXS and PhDXR could play significant roles in terpenoids biosynthesis at molecular levels. Meanwhile, as nuclear genes among MEP pathway, PhDXS and PhDXR could provide a new way of thinking to research the problem of chromalveolata biological evolution.

• 한국생명과학회:학술대회논문집
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• 한국생명과학회 2001년도 제34회 학술심포지움
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• pp.3-8
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• 2001

Isopentenyl diphosphate (IPP) is the common, five-carbon building block in the biosynthesis of all carotenoids, IPP in Escherichia coli is synthesized through the non-mevalonate pathway. The first reaction of IPP biosynthesis in E. coli is the formation of 1-deoxy-D-xylulose-5-phosphate (DXP), catalyzed by DXP synthase and encoded by dxs. The second reaction in the pathway is the reduction of DXP to 2-C-methyl-D-erythritol-4-phosphate, catalyzed by DXP reductoisomerase and encoded by dxr. To determine if one or more of the reactions in the non-mevalonate pathway controlled flux to IPP, dxs and dxr were placed on several expression vectors under the control of three different promoters and transformed into three E. coli strains (DH5(, XL1-Blue, and JM101) that had been engineered to produce lycopene. Lycopene production was improved significantly in strains transformed with the dxs expression vectors. When the dxs gene was expressed from the arabinose-inducible araBAD promoter (PBAD) on a medium-copy plasmid, lycopene production was 2-fold higher than when dxs was expressed from the IPTG-inducible trc and lac promoters (Ptrc and Plac, respectively) on medium-copy and high-copy plasmids, Given the low final densities of cells expressing dxs from IPTG-inducible promoters, the low lycopene production was probably due to the metabolic burden of plasmid maintenance and an excessive drain of central metabolic intermediates. At arabinose concentrations between 0 and 1.33 mM, cells expressing both dxs and dxr from PBAD on a medium-copy plasmid produced 1.4 - 2.0 times more lycopene than cells expressing dxs only. However, at higher arabinose concentrations lycopene production in cells expressing both dxs and dxr was lower than in cells expressing dxs only. A comparison of the three E. coli strains transformed with the arabinose-inducible dxs on a medium-copy plamid revealed that lycopene production was highest in XL1-Blue.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2001년도 Proceedings of 2001 International Symposium
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• pp.141-145
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• 2001

Isopentenyl diphosphate (IPP) is the common, five-carbon building block in the biosynthesis of all carotenoids. IPP in Escherichia coli is synthesized through the non-mevalonate pathway. The first reaction of IPP biosynthesis in E. coli is the formation of l-deoxy-D-xylulose-5-phosphate (DXP), catalyzed by DXP synthase and encoded by dxs. The second reaction in the pathway is the reduction of DXP to 2-C-methyl-D-erythritol-4-phosphate, catalyzed by DXP reductoisomerase and encoded by dxr. To determine if one or more of the reactions in the non-mevalonate pathway controlled flux to IPP, dxs and dxr were placed on several expression vectors under the control of three different promoters and transformed into three E. coli strains (DH5$\alpha$, XL1-Blue, and JMl0l) that had been engineered to produce lycopene. Lycopene production was improved significantly in strains transformed with the dxs expression vectors. When the dxs gene was expressed from the arabinose-inducible araBAD promoter ( $P_{BAD}$) on a medium-copy plasmid, lycopene production was 2-fold higher than when dxs was expressed from the IPTG-inducible trc and lac promoters ( $P_{trc}$ and $P_{lac}$, respectively) on medium-copy and high-copy plasmids. Given the low final densities of cells expressing dxs from IPTG-inducible promoters, the low lycopene production was probably due to the metabolic burden of plasmid maintenance and an excessive drain of central metabolic intermediates. At arabinose concentrations between 0 and 1.33 roM, cells expressing both dxs and dxr from $P_{BAD}$ on a medium-copy plasmid produced 1.4 - 2.0 times more lycopene than cells expressing dxs only. However, at higher arabinose concentrations lycopene . production in cells expressing both dxs and dxr was lower than in cells expressing dxs only. A comparison of the three E. coli strains transformed with the arabinose-inducible dxs on a medium-copy plasmid revealed that lycopene production was highest in XLI-Blue.LI-Blue.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.70-73
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• 2001

Isopentenyl diphosphate (IPP) is the common, five-carbon building block in the biosynthesis of all isoprenoids. IPP in Escherichia coli is synthesized through the non-mevalonate pathway. The first reaction of IPP biosynthesis in E. coli is the formation of 1-deoxy-D-xylulose-5-phosphate(DXP), catalyzed by DXP synthase and encoded by dxs. The second reaction in the pathway is the reduction of DXP to 2-C-methyl-D-erythritol-4-phosphate, catalyzed by DXP reductoismerase and encoded by dxr. To determine if one of more of the reactions in the non-mevalonate pathway controlled flux to IPP, dxs and dxr were placed on several expression vectors under the control of three different promoters and transformed into three E. coli strains ($DH5{\alpha}$, XL1-Blue, and JM101) that had been engineered to produce lycopene, a kind of isoprenoids. Lycopene production was improved significantly in strains transformed with the dex expression vectors. At arabinose concentrations between 0 and 1.33 mM, cells expressiong both dxs and from $P_{BAD}$ on a midium-copy plasmid produced 1.4 -2.0 times more lycopene than cells expressing dxs only. However, at higher arabinose concentrations lycopene production in cell expressing both dxs and dxr was lower than in cells expression dxs only. A comparison of the three E. coli strains trasfomed with the arabinose-inducible dxs on a medium-copy plasmid revealed that lycopene production was highest in XL1-Blue.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 1994년도 춘계학술대회 and 제3회 신약개발 연구발표회
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• pp.190-190
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• 1994

아급성독성시험 : DA-125를 1.0, 0.2, 0.04 mg/kg/day의 용량으로 4주간 정맥내투여시 고용량군에서만 세포분화가 빠른 골수, 비장, 흉선 등의 장기에서 독성이 나타났으며 중간 및 저용량군에서는 독성변화가 나타나지 않았다. 2)항원성시험 : DA-125는 단독 또는 면역보조제(CFA)와의 혼합감작에 의하여 능동전신성 또는 수신피부 아나필라시스를 일으키지 않았으며 면역확산법에 의해서도 항체가 확인되지 않았다. 면역독성시험에서 DA-125는 흉선, 비장의 위축과 임파구중식억제를 나타냈으나 그 정도는 DXR보다 경미하였다. 3)혈완장해시험 : 0.4%의 DA-125 용액은 토끼의 이개정맥내 정맥주사 및 저류시에 혈전형성이나 염증반응 등의 혈관장해를 나타내지 않았으나, 0.2%의 DXR용액은 약한 염증반응을 보였다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2012년도 정기총회 및 춘계학술발표회
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• pp.20-20
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• 2012

Isoprenoids represent the most diverse group of metabolites, which are functionally and structurally identified in plant organism to date. Ginsenosides, glycosylated triterpenes, are considered to be the major pharmaceutically active ingredient of ginseng. Its backbones, categorized as protopanaxadiol (PPD), protopanaxatriol (PPT), and oleanane saponin, are synthesized via the isoprenoid pathway by cyclization of 2,3-oxidosqualene mediated with dammarenediol synthase or beta-amyrin synthase. The rate-limiting 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR), which is the first committed step enzyme catalyzes the cytoplasmic mevalonate (MVA) pathway for isoprenoid biosynthesis. DXP reductoisomerese (DXR), yields 2-C-methyl-D-erythritol 4-phosphate (MEP), is partly involved in isoprenoid biosynthesis via plastid. Squalene synthase and squalene epoxidase are involved right before the cyclization step. The triterpene backbone then undergoes various modifications, such as oxidation, substitution, and glycosylation. Here we will discuss general biosynthesis pathway for the production of ginsenoside and its modification based on their subcellular biological functions.