• Journal of Microbiology and Biotechnology
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• 제33권1호
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• pp.83-95
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• 2023

These days, bacterial detection methods have some limitations in sensitivity, specificity, and multiple detection. To overcome these, novel detection and identification method is necessary to be developed. Recently, NGS panel method has been suggested to screen, detect, and even identify specific foodborne pathogens in one reaction. In this study, new NGS panel primer sets were developed to target 13 specific virulence factor genes from five types of pathogenic Escherichia coli, Listeria monocytogenes, and Salmonella enterica serovar Typhimurium, respectively. Evaluation of the primer sets using singleplex PCR, crosscheck PCR and multiplex PCR revealed high specificity and selectivity without interference of primers or genomic DNAs. Subsequent NGS panel analysis with six artificially contaminated food samples using those primer sets showed that all target genes were multi-detected in one reaction at 10⁸-10⁵ CFU of target strains. However, a few false-positive results were shown at 10⁶-10⁵ CFU. To validate this NGS panel analysis, three sets of qPCR analyses were independently performed with the same contaminated food samples, showing the similar specificity and selectivity for detection and identification. While this NGS panel still has some issues for detection and identification of specific foodborne pathogens, it has much more advantages, especially multiple detection and identification in one reaction, and it could be improved by further optimized NGS panel primer sets and even by application of a new real-time NGS sequencing technology. Therefore, this study suggests the efficiency and usability of NGS panel for rapid determination of origin strain in various foodborne outbreaks in one reaction.

• Journal of Pharmaceutical Investigation
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• 제36권4호
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• pp.231-237
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• 2006

Hypoxia in solid tumors is known to contribute to intrinsic chemoresistance. Histocultures are in vitro 3 dimensional cultures of tumor tissues and maintain the characteristic microenvironment of human solid tumors in vivo including hypoxia and multicellular structure. In this study, we evaluated the pharmacodynamics of tirapazamine(TPZ), a hypoxia-selective cytotoxin, in human non small cell lung cancer(NSCLC) cells grown as monolayers and histocultures. Antiproliferative activity of TPZ was determined after various conditions of drug exposure, and cell cycle arrest and apoptosis were also measured using flow cytometry. In monolayers, hypoxia selectivity measured by hypoxic/normoxic cytotoxicity ratio was increased with longer exposure. Lower cytotoxicity of TPZ was observed in histocultures compared to monolayers, however, a similar level of cytotoxicity was obtained with longer exposure of 96 hr. TPZ induced $G_2/M$ arrest and apoptosis in both culture conditions, which were greatly enhanced under hypoxic condition. Our data clearly showed the different pharmacodynamics of TPZ in monolayers and histocultures. Antiproliferative activity of TPZ against human solid tumors can be improved with longer drug exposure by exploiting drug delivery systems or by combining angiogenesis inhibitors to maintain drug concentration in tumor tissues.

• 한국식품위생안전성학회지
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• 제26권1호
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• pp.12-15
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• 2011

코엔자임 Q10은 우리나라뿐 아니라 여러나라에서 각광받고 있는 건강기능식품 중 하나로 이에 대한 분석법을 마련하고 이에 대한 분석법 검증을 하고자하였다. 분석기기로는 HPLC를 사용하였으며 분석법 검증을 위하여 직선성, 선택성, LOD, LOQ, 정밀성, 정확성을 확인하였다. 또한 현재 유통 중인 개별인정형 건강기능식품의 코엔자임 Q10 함량을 모니터링 한 결과 모든 제품이 적합함을 알 수 있었다. 따라서 확립된 분석 방법은 신속하고 효과적으로 분석하는데 이용될 수 있을 것이며, 개별인정형제품의 코엔자임 Q10이 공전에 등재시 본 연구결과가 시험법으로 활용할 수 있을 것으로 사료된다.

• Archives of Pharmacal Research
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• 제26권11호
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• pp.892-897
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• 2003

Anticancer drugs have serious side effects arising from their poor malignant cells selectivity, Since insulin receptors highly express on the cytomembrane of some kind of tumor cells, using insulin as the vector was expected to reduce serious side effects of the drugs. The objective of this study was to evaluate the tumor targeting effect of the newly synthesized mitoxantrone-insulin conjugate (MIT-INS) with the drug loading of 11.68%. In vitro stability trials showed MIT-INS were stable in buffers with different pH (2-8) at $37^{\circ}C$ within 120 h (less than 3% of free MIT released), and were also stable in mouse plasma within 48 h (less than 1 % of free MIT released). In vivo study on tumor-bearing mice showed that, compared with MIT [75.92 $\mu g \cdot$ h/g of the area under the concentration-time curve (AUC) and 86.85 h of mean residence time (MRT)], the conjugates had better tumor-targeting efficiency with enhanced tumor AUC of 126.53 1l9 h/g and MTR of 151.95 h. The conjugate had much lower toxicity to most other tissues with targeting indexes ($TI^c$) no larger than 0.3 besides good tumor targeting efficiency with $TI^c$ of 1.67. The results suggest the feasibility to promote the curative effect in ca.ncer chemotherapy by using insulin as the vector of anti-cancer drugs.

• 한국환경농학회지
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• 제39권3호
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• pp.246-252
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• 2020

BACKGROUND: Pesticides are broadly used to control weeds and pests, and the residues remaining in crops are managed in accordance with the MRLs (maximum residue limits). Therefore, an analytical method is required to quantify the residues, and we conducted a series of analyses to select and validate the quick and simple analytical method for tolpyralate in five agricultural products using QuEChERS (quick, easy, cheap, effective, rugged and safe) method and LC-MS/MS (liquid chromatography-tandem mass spectrometry). METHODS AND RESULTS: The agricultural samples were extracted with acetonitrile followed by addition of anhydrous magnesium sulfate, sodium chloride, disodium hydrogencitrate sesquihydrate and trisodium citrate dihydrate. After shaking and centrifugation, purification was performed with d-SPE (dispersive-solid phase extraction) sorbents. To validate the optimized method, its selectivity, linearity, LOD (limit of detection), LOQ (limit of quantitation), accuracy, repeatability, and reproducibility from the inter-laboratory analyses were considered. LOQ of the analytical method was 0.01 mg/kg at five agricultural products and the linearity of matrix-matched calibration were good at seven concentration levels, from 0.0025 to 0.25 mg/L (R²≥0.9980). Mean recoveries at three spiking levels (n=5) were in the range of 85.2~112.4% with associated relative standard deviation values less than 6.2%, and the coefficient of variation between the two laboratories was also below 13%. All optimized results were validated according to the criteria ranges requested in the Codex Alimentarius Commission (CAC) and Ministry of Food and Drug Safety (MFDS) guidelines. CONCLUSION: In conclusion, we suggest that the selected and validated method could serve as a basic data for detecting tolpyralate residue in imported and domestic agricultural products.

• 한국환경농학회지
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• 제32권3호
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• pp.207-213
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• 2013

Thidiazuron은 1976년 Plant Physiology 발표를 통해 생장조정제로 알려진 이후, 현재 우리나라에서도 생장조정제로 수박과 참외의 착과 증진 및 참다래의 과실비대 촉진, 포도의 과립 비대 증진 및 착립 증진 등을 위해 등록되어 사용되고 있다. Thidiazuron의 분석법은 식품공전에 수재되어 있으나, 등재 당시의 기술 이용, 일부 시험 대상 품목에 대한적용 등으로, 최근의 잔류허용기준 설정 품목의 증가와 분석기기 및 기술 발달을 반영하여 검증된 분석법으로 개선코자 하였다. 더불어, 개발된 분석법을 활용하여, thidiazuron의 사용이 허가되어 있는 수박, 키위, 포도를 포함한 국민 다소 비 식품 17품목에 대한 잔류실태조사도 수행하였다. 개발된 분석법의 회수율은, 현미 89.2~91.2 %, 고추 87.2~92.1 %, 감자 76.4~86.9 %, 수박 91.2~95.7 %, 키위 86.5~88.5 %, 포도 89.5~94.0 % 였으며, 반복 회수율 간 변이계수는 10 % 이하였다. 또한 개발된 분석법으로 우리나라에서 유통되고 있는 다소비 농산물 쌀, 상추, 사과 등 17품목 358건에 대해 농약 잔류실태를 조사한 결과 모든 시료에서 thidazulon은 검출되지 않았다.

• 동의생리병리학회지
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• 제23권2호
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• pp.494-498
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• 2009

The emergence and spread of drug-resistant malaria parasites is a serious public health problem in the tropical world. Useful antimalarial drugs such as chloroquine have resistance in the world now. Moreover, other antimalarialdrugs such as mefloquine, halofantrine, atovaquone, proguanil, artemether and lumefantrine retain efficacy but have limitations, one of which is their high cost. New antimalarial drugs are clearly needed now. Cytotoxicity assay and susceptibility assay were performed for the selectivity of herb extracts in vitro. On the basis of high selectivity, 4-day suppressive test and survival test were progressed in Plasmodium berghei-infected mice. The selectivity of Areca catechu L. (ACL) and butanol extract of ACL (ACL-BuOH extract) were 3.4 and 3.0 in vitro, respectively. Moreover in vivo, 4-day suppressive test showed 39.1 % inhibition effect after treated with 150 mg/kg/day ACL-BuOH to P. berghei-infected mice. Survival test also showed 60% survival rate with ACL-BuOH-treated group while all other group mice died. In this study, ACL and ACL-BuOH were investigated for antimalarial activity in vitro and in vivo and they showed a potent antimalarial activity. In particular,ACL-BuOH could specifically lead higher survival rate of mice in vivo. Therefore ACL-BuOH would be a candidate of antimalarial drugs.

• 한국식품위생안전성학회지
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• 제29권4호
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• pp.312-315
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• 2014

페놀은 보통 대기로 배출되며 반감기가 비교적 짧은 물질로서 환경에 농축되는 경우는 드물다. 하지만, 누출사고가 발생되어 수계나 토양에 오염될 경우 페놀에 오염된 농수산물의 안전성을 확보하기 위하여 페놀을 정확하게 검출할 수 있는 시험법을 확립하고자 하였다. 식품 중 페놀을 초음파추출기로 추출하고 GPC로 정제하여 GC/MS로 분석하는 시험법을 확립하였으며, 시험법의 유효성 확인을 위한 실험 결과들이 AOAC 가이드라인에서 제시하는 Criteria를 만족함으로써 시험법의 신뢰성을 확보할 수 있었다. 확립된 시험법은 식품 중 페놀의 오염조사 및 이행률 조사에 활용될 수 있다.

• Journal of Pharmaceutical Investigation
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• 제41권2호
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• pp.59-65
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• 2011

Nanotechnology for cancer therapy is playing a pivotal role in dramatically improving current approaches to cancer detection, diagnosis, and therapy while reducing toxic side effects associated with previous cancer therapy. A widespread understanding of these new technologies will lead to develop the more refined design of optimized nanoparticles with improved selectivity, efficacy and safety in the clinical practice of oncology. This review provides an integrated overview of applications and advances of nanotechnology in cancer therapy, based on molecular diagnostics, treatment, monitoring, target drug delivery, approved nanoparticle-based chemotherapeutic agents, and current clinical trials in the development of nanomedicine and ultimately personalized medicine.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.126.2-127
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• 2003

The therapeutic potential of currently available antiarrhythmic drugs is limited by their tendency to induce proarrhythmic and extracardiac side effects. An ideal antiarrhythmic agent would selectively prolong the action potential duration more in extraordinarily depolarized cardiac myocytes than in normal cells. and show tissue selectivity. Voltage-gated K+ (Kv) channels represent a structurally and functionally diverse group of membrane proteins. (omitted)