• Journal of Microbiology and Biotechnology
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• 제25권3호
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• pp.393-398
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• 2015

Aptamers are composed of single-stranded oilgonucleotides that can selectively bind desired molecules. It has been reported that RNA or DNA could act as not only a genetic messenger but also a catalyst in metabolic pathways. RNA aptamers (average sizes 40-50 bp) are smaller than antibodies and have strong binding capacities to target molecules, similar to antigenantibody interactions. Once an aptamer was selected, it can be readily produced in large quantities at low cost. The objectives of this study are to screen and develop aptamers specific to oral pathogens such as Porphyromonas gingivalis, Treponema denticola, and Streptococcus mutans. The bacterial cell pellet was fixed with formaldehyde as a target molecule for the screening of aptamers. The SELEX method was used for the screening of aptamers and a modified western blot analysis was used to verify their specificities. Through SELEX, 40 kinds of aptamers were selected and the specificity of the aptamers to the bacterial cells was confirmed by modified western blot analysis. Through the SELEX method, 40 aptamers that specifically bind to oral pathogens were screened and isolated. The aptamers showed possibility as effective candidates for the detection agents of oral infections.

• 한국약용작물학회지
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• 제20권4호
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• pp.222-230
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• 2012

We evaluated the inhibitory effects of extracts and components of Geranium thunbergii on aldose reductase (AR) and galactitol formation in rat lenses with high levels of galactose as a part of our ongoing search of natural sources for therapeutic and preventive agents for diabetic complications. The inhibitory effects of water, methanol and ethanol extracts of G. thunbergii on rat lens AR (RLAR) were determined. Comparing inhibitory effects of various solvent extracts, ethanol extract showed RLAR inhibitory activity ($IC_{50}$ values, 5.24 and $6.39{\mu}g/m{\ell}$, respectively). The ethanol extract was fractionated to chloroform, ethyl acetate and water. Of these, the ethyl acetate fraction from ethanol extract of G. thunbergii exhibited RLAR inhibitory activity ($IC_{50}$ value, $2.64{\mu}g/m{\ell}$). In order to identify the bioactive components of ethyl acetate soluble fraction of ethanol extract from G. thunbergii, eight compounds, namely gallic acid (1), protocatechuic acid (2), p-hydroxybenzoic acid (3), brevifolin carboxylic acid (4), geraniin (5), ellagic acid (6), kaempferol-3-O-arabinofuranosyl-7-O-rhamnopyranoside (7), kaempferitrin (8) were isolated. The isolates were subjected to in vitro bioassays to evaluate their inhibitory activity on RLAR and galactitol formation in rat lenses. The ellagic tannins (5, 6) and flavonoid (7) exhibited strong inhibitory effects on RLAR. Also, these three compounds (5, 6 and 7) suppressed galactitol accumulation in rat lens under high galactose conditions, demonstrating the potential to prevent galactitol accumulation exo vivo. These results suggest that the extracts and components of G. thunbergii are a promising agent in the prevention or treatment of diabetic complications.

• Preventive Nutrition and Food Science
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• 제14권3호
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• pp.179-187
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• 2009

Five kinds of coumarin compounds were successfully purified from Angelica gigas Nakai by using recyclingpreparative HPLC and identified as decursin (1), decursinol angelate (2), 7-demethylsuberosine (3), marmesin (4), and decursinol (5) by NMR analyses. None of the purified compounds in ethanol showed DPPH radical scavenging activity, while the A. gigas extract (AGNEX) displayed a significant level of activity. Interestingly, compounds 3 in phosphate buffered saline (PBS) showed good $ABTS^+$ radical scavenging activity ($IC_{50}=8.1{\mu}g$/mL) as did compounds 4 and 5. The anti-inflammatory activities of the purified compounds were evaluated and compared using the NO concentration assay and western blot analysis on LPS-stimulated RAW 264.7 cells. NO production was significantly suppressed by all the compounds in a dose-dependent manner among which compounds 1, 2, and 3 showed very good activities with $IC_{50}$ values of 7.4, 6.5, and $7.6{\mu}g$/mL, respectively. Treatment with compounds 1-5 effectively suppressed the expression levels of iNOS, IL-1$\beta$, and COX-2, which are responsible for promoting the inflammatory process. Thus, the ethanol extract and coumarin compounds of A. gigas Nakai hold promise for use as potential anti-inflammatory agents.

• Preventive Nutrition and Food Science
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• 제6권1호
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• pp.38-42
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• 2001

The methanol extracts of 25 leguminous seeds in vitro were evaluated for inhibitory activities against lens aldose reductase of Sprague Dawley male rats. The responses varied with both leguminous seed and concentration used. At the concentration of 0.1 mg/mL, the methanol extracts from Amphicaraea edgeworthii, Canavalia lineata, Gylcine max var. solitae, Glycine max var. yagkong, Glycine max var. hooktae, Glycine max var. bangkong, Glycine max var. geumdu, Glycine max var. chungtae, Glycine max var. mejukong, Glycine soja, Phaseolus radiatus var. geodu, Vicia tetrasperma, Vigna angulasis, and Vigna sinensis inhibited enzyme activity by greatertha 60%. In following study, at the concentration of 0.01 mg/mL, the extracts of C. lineata and V. tetraspermahad relatively strong inhibitory activity against aldose reductase. Because of their potent inhibitory activities, the activity of each solvent fraction from C. lineata and V. tetrasperma was determined, and the potent activity was showed from chloroform and hexane fractions, respectively. {TEX}$IC_{50}${/TEX} values of C. lineata and V. tetrasperma were 0.004 and 0.006 mg/mL, respectively. As a naturally occurring therapeutic agent, leguminous seeds described could be useful for developing new agents of antidiabetic complications.

• Preventive Nutrition and Food Science
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• 제7권4호
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• pp.373-377
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• 2002

Allergens in processed foods may place persons with food allergies at significant risk when the labels do not Provide sufficient warnings or identification of high-risk ingredients. Because egg proteins are common food allergens, this study was carried out to identify hen's egg albumin (ovalbumin, OVA) in five commercially processed foods containing egg (custayd, cookie and pasta), and chicken meat (sausage and meatball) by immunological methods using commercially produced murine monoclonal immunoglobulin G (M-IgG), immunoblotting and enzyme linked immunosorbent assay (ELISA). Sample buffer with chelating and reducing agents was prepared and used for the preparation of the protein fractions from the foods. Most bands in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) profile (5~15% gradient gel) presented at 75 kDa below. OVA (43 kDa) in the sample lanes could not be visually observed on the gel. However, OVA in solutions prepared from custard and cookie could be detected by M-IgG, but were not detected in sausage and pasta. OVA in all samples could be quantitatively determined by the equation obtained from the standard curve by ELISA. Cookie and custard containing egg white and egg, respectively, contained very high concentrations of OVA. OVA in the other products were present in relatively low concentrations, but sufficiently high to pose possible risk of allergy, ELISA is a very sensitive and precise method for the identification and quantification of allergens in food products including allergy-inducible materials.

• Preventive Nutrition and Food Science
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• 제6권1호
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• pp.6-9
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• 2001

Minimal inhibitory concentrations (MIC) and antimicrobial effects of glycerol monolaurate (monolaurin) and organic acids, either alone or in combination, against Escherichia coli O157:H7 in tryptic soy broth were determined. MIC values of monolaurin(ML), acetic (AA), citric (CA), lactic (LA) and hydrochloric acid (HCl) were 300$\mu\textrm{g}$/mL (0.03%), 1250$\mu\textrm{g}$/mL(0.125%), 5000$\mu\textrm{g}$/mL(0.5%), 2500$\mu\textrm{g}$/mL(0.25%) and 2500$\mu\textrm{g}$/mL(0.25), respectively. When 150$\mu\textrm{g}$/mL of ML was combined with 50$\mu\textrm{g}$/mL AA, 250$\mu\textrm{g}$/mL HCl and 125$\mu\textrm{g}$/mL LA, the combined agents did not increase the inhibitory effect of the most active single compound alone. This result indicates that there was little interaction between ML and A, HCl and LA. However, the combination of 150$\mu\textrm{g}$/mL ML and 250$\mu\textrm{g}$/mL CA synergistically inhibited growth of E. coli O157:H7. The present study showed that the nature of combined antimicrobial response against E. coli O157:H7 was complex, but this information would be useful for determining interaction that could compromise effectiveness in food systems.

• Preventive Nutrition and Food Science
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• 제20권1호
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• pp.73-77
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• 2015

As an approach to search for chemopreventive agents, we tested p-coumaric acid, 3-methoxy-p-coumaric acid (ferulic acid), and 3,5-dimethoxy-p-coumaric acid (sinapic acid) in B16/F10 melanoma cells. Intracellular melanin contents were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and cytotoxicity of the compounds were examined by lactate dehydrogenase (LDH) release. p-Coumaric acid showed inhibitory effect on melanogenesis, but ferulic acid increased melanin content, and sinapic acid had almost no effect on melanogenesis. Treatment with ferulic acid resulted in a 2 to 3 fold elevation in the production of melanin. Correlatively, cell viability decreased in a dose-dependent manner when treated with ferulic acid. However, ferulic acid did not affect the LDH release from the cells. Treatment with sinapic acid resulted in a 50~60% elevation in the release of LDH when treated with a $200{\mu}g/mL$ concentration and showed neither cytostasis nor increase of melanin synthesis in a dose-dependent manner. Taken together, p-coumaric acid inhibits melanogenesis, ferulic acid induces melanogenesis, and sinapic acid exerts cytotoxic effects in B16/F10 murine melanoma cells. The results indicate that the addition of methoxy groups to p-coumaric acid shows the melanogenic or cytotoxic effects in melanoma cells compared to the original compound. Therefore, this study suggests the possibility that methoxylated p-coumaric acid, ferulic acid can be used as a chemopreventive agent.

• 동의생리병리학회지
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• 제34권2호
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• pp.75-80
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• 2020

In this study, we investigated the dose-dependent effects of mixtures of Atractylodes macrocephala (AM) and Amomum villosum (AV) water extracts in a ratio of 3:1 on high fat diet (HFD)-induced obesity model. Oral administration of various concentrations with mixtures of AM and AV extracts in a ratio of 3:1 for 6 weeks inhibited HFD-induced increases of body, liver and epididymal fat weights in a dose-dependent fashions. Those effects may be mediated by decreased expressions of lipogenesis-related genes such as acetyl coA carboxylase (ACC) and fatty acid synthase (FAS) in liver. Also, increase of insulin and decrease of adiponectin in serum by HFD supply were inhibited by three different dosages of mixtures of AM and AV extracts in a ratio of 3:1. HFD supply induced increases of serum total cholesterol, triglyceride and LDL cholesterol. However, hyperlipidemia was significantly decreased in dose-dependent manners by treatment with mixtures of AM and AV extracts. Based on the results of the present study, hypolipidemic and anti-obesity effects by mixtures of AM and AV extracts were found in HFD-induced obesity model. Further clinical investigation is needed to develop anti-obesity therapeutic or preventive agents by using mixtures of AM and AV extracts.

• Childhood Kidney Diseases
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• 제24권1호
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• pp.1-13
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• 2020

Immunoglobulin (Ig)A vasculitis nephritis (IgAVN), also referred to as Henoch-Schönlein purpura nephritis, is a relatively benign disease in children. However, two 24-year European cohort studies have reported high sustained rates of hypertension, severe proteinuria, and renal dysfunction in patients with IgAVN. Notably, the incidence and exacerbation rates of proteinuria, hypertension, and renal dysfunction during pregnancy were high even in women who recovered from IgAVN before pregnancy. Patients with IgAVN need lifelong care. Trials have been performed to investigate early biomarkers and genes associated with poor prognosis to identify high-risk patients in whom IgAVN may progress to severe renal disease. Urinary IgA/cr, IgM/cr levels, and HLAB35 and angiotensinogen gene expression were shown to be predictors of progression of IgAVN to severe renal dysfunction. The 2019 Single Hub and Access point for paediatric Rheumatology in Europe (SHARE) initiative group published guidelines for pediatric IgAVN, following the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines established in 2012. Compared with the KDIGO guidelines, the SHARE guidelines recommend earlier corticosteroid administration in cases of mild proteinuria (>0.5 g/d). Clinical trials of targeted budesonide delivery to the distal ileum, monoclonal antibody targeting C5, eculizumab and anti-CD20 monoclonal antibody administration, among others are currently underway in patients with IgA nephropathy. It is expected that newer therapeutic agents would become available for IgAVN in the near future. This review summarizes IgAVN with emphasis on recently published literature, including possible preventive strategies, predictive biomarkers for progression of IgAVN, and various treatments.

• 대한핵의학회:학술대회논문집
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• 대한핵의학회 1999년도 제38차 춘계학술대회
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• pp.205-208
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• 1999

재협착에 관여하는 인자는 매우 다양하다. 평활근 세포의 증식, ECM의 형성, 혈관벽의 초기 혈전형성, 그리고 혈관 재형성 등이 모든 것들이 재협착의 병인에 기여하고 있다. 환자마다 이런 요소들의 기여정도가 다르며 동일 환자에서도 병변에 따른 기여정도가 또한 다르리라 여긴다. 그러나 아직까지 우리는 외막섬유모세포의 역할, 내피세포의 재생, 증식세포의 계획된 죽음 등 재협착의 기전을 불완전하게 이해하고 있고 따라서 보다 완전한 이해를 통해 효과적인 재협착 예방치료가 시행될 수 있을 것이다.