• KSBB Journal
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• 제22권6호
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• pp.426-432
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• 2007

QDs을 기반으로 하는 OsFIA는 매우 빠르고 간단히 수행될 수 있다. 또한 이 분석법은 고체상의 담체나 결합/잔류시약의 분리 등과 같은 여러 과정을 필요로 하지 않으며, 적은 양의 시약으로도 분석이 가능하다. 본 분석법은 높은 감도로 항원을 측정할 수 있으며, 일상적인 분석에도 쉽게 도입될 수 있을 것이다. 선형 범위 내에서 측정 가능한 receptor의 최소농도는 0.05 nM (2.65 ng/mL) 정도이다. 또한, 일반적으로 상용화된 항체를 가치고 수행이 가능하다. 이 OsFIA 분석법은 기존의 실험적 sandwich immunoassay의 효과적인 대안으로 제시된다.

• Biomolecules & Therapeutics
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• 제19권1호
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• pp.1-8
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• 2011

G-protein coupled receptors (GPCRs) constitute an important class of drug targets and are involved in every aspect of human physiology including sleep regulation, blood pressure, mood, food intake, perception of pain, control of cancer growth, and immune response. Radiometric assays have been the classic method used during the search for potential therapeutics acting at various GPCRs for most GPCR-based drug discovery research programs. An increasing number of diverse small molecules, together with novel GPCR targets identified from genomics efforts, necessitates the use of high-throughput assays with a good sensitivity and specificity. Currently, a wide array of high-throughput tools for research on GPCRs is available and can be used to study receptor-ligand interaction, receptor driven functional response, receptor-receptor interaction,and receptor internalization. Many of the assay technologies are based on luminescence or fluorescence and can be easily applied in cell based models to reduce gaps between in vitro and in vivo studies for drug discovery processes. Especially, cell based models for GPCR can be efficiently employed to deconvolute the integrated information concerning the ligand-receptor-function axis obtained from label-free detection technology. This review covers various platform technologies used for the research of GPCRs, concentrating on the principal, non-radiometric homogeneous assay technologies. As current technology is rapidly advancing, the combination of probe chemistry, optical instruments, and GPCR biology will provide us with many new technologies to apply in the future.

• 한국식물병리학회지
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• 제14권6호
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• pp.559-562
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• 1998

Odontoglossum ringspot virus (ORSV) was finally purified from ORSV-infected orchid plants by diethylaminoethyl (DEAE) cellulose anion exchange column chromatography. The virus was reliably eluted by potassium chloride at the concentration from 0.1 M to 0.13 M. Partial purification was done by solubilization with Triton X-100 (allkylphenoxypolyethoxy ethanol) and precipitation with polyethylene glycol (PEG; MW 8,000). The finally purified ORSV represented one distinct homogeneous band and the molecular weight of its capsid protein was about 17,500 Dalton in electrophoretic analysis. Electron microscopy showed not only intact particles ranged from 280 nm to 340 nm in length, but also segmented particles that final 140 nm to 220 nm and even disks. Enzyme-linked immunosorbent assay (ELISA) showed that final yield was 12 mg/100 g of the infected leaves. Bioassay demonstrated that the purified ORSV had the normal infectivity to orchid plants and Nicotiana glutionsa. Based on these data, anion exchange column chromatography could be efficiently applied to the purification of ORSV and other viruses similar to ORSV.

• 한국동물학회지
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• 제36권4호
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• pp.522-528
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• 1993

Monoclonal antibodies (MAbs) against human alpha-fetoprotein (AFPI was produced by hybridizing SP 210-Ag 14 mouse myeloma cells with spleen cells of Balb/c mice immunized with purified AFP. Two subclones (D-6 and I-6) were expanded as ascite tumors in svngenic mice, and from ascitic fluid immunoglbulins were Pruified. Each anibodv was identified to be homogeneous by several criteria, and the affinity constant of D-6 and I-6 MAb to AEP was calculated to be 4.2${\times}$10-8 and 6.4${\times}$10-8 M-1, respectively. With these MAbs sensitive and accurate enzyme linked immunosorbent assay method was established.

• Bulletin of the Korean Chemical Society
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• 제11권1호
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• pp.54-58
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• 1990

Acid-base equilibria and spectroscopic properties of diazepam and chlorodiazepoxide were investigated in sodium dodecyl sulfate (SDS) micellar solutions as functions of pH. The results were compared with the behaviors in homogeneous aqueous media. The presence of SDS increased the $pK_a$ of chlorodiazepoxide to 6.3 from 4.7, while it has little effect on the $pK_a$ of diazepam. The acidic protonated form of diazepam was moderately fluorescent when the solution was excited at 350 nm, and emissnion intensity of the species was enhanced about 5 fold by the presence of SDS. On the other hand, the acidic solution of chlorodiazepoxide was non-fluorescent, but the neutral solution of the compound was fluorescent upon excitation at 350 nm. The emission peak of the neutral chlorodiazepoxide shifted to shorter wavelength region without significant change in the emission intensity upon the addition of SDS. Procedures for assay of the individual drugs from their mixture by the use of SDS micelle were discussed.

• 한국산학기술학회논문지
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• 제16권8호
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• pp.5492-5500
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• 2015

LDL-콜레스테롤(LDL-C)은 심뇌혈관질환의 주된 교정 가능한 위험인자로서, 정확한 측정값을 임상에 적용하는 것이 중요하다. 하지만 LDL-C의 측정은 실제 측정이 아닌 Friedewald 공식에 의한 계산방법이 널리 이용되고 있다. 본 연구의 목적은 LDL-C의 Friedewald-추정값과 실측값을 비교하고, 두 방법의 LDL-C 위험수준 분류 일치도를 평가하는 것이다. 표본은 국민건강영양조사 2개년(2009년과 2010년)의 공개된 자료에서 추출되었고, 혈액 검사에서 총 콜레스테롤, HDL-콜레스테롤, 직접 측정한 LDL-C, 그리고 중성지방 중 어느 한 결측치도 없는 4,319명을 연구대상으로 하였다. 중성지방 400 mg/dL 미만일 때, Friedewald-추정값과 실측값은 높은 상관관계를 보였고 (r = 0.958, p < 0.001), 위험수준 분류 일치 백분율은 82.7%이었다. 중성지방 수준이 높을수록, 일치 백분율은 낮았다. 중성지방 수준 150 mg/dL 미만, 150-200 mg/dL, 그리고 200-399 mg/dL일 때, 일치 백분율은 각각 85.4%, 78.2%, 그리고 71.4%이었다. Friedewald 공식은 중성지방 농도 150 mg/dL 미만에서는 LDL-C를 과대평가하는 반면, 중성지방 농도 150 mg/dL 이상에서는 과소평가하는 경향이 있었다. 이에 따라 LDL-C 위험수준 분류에 있어 그 범주가 과대평가된 사람은 382명 (9.1%)인 반면, 과소평가된 사람은 348명 (8.3%)이었다. 이러한 결과는 Friedewald-추정값의 LDL-C 과소평가뿐만 아니라, 과대평가도 심각한 문제일 수 있음을 제시한다.

• Parasites, Hosts and Diseases
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• 제55권4호
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• pp.409-416
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• 2017

The high prevalence of pediculosis capitis, commonly known as head lice (Pediculus humanus capitis) infestation, has led to the preparation of a community-based pediculicidal ointment, which is made of common household items and the extract of Tinospora crispa stem. The present study aimed to evaluate the safety, efficacy, and physicochemical characteristics of the T. crispa pediculicidal ointment. The physicochemical properties of the ointment were characterized, and safety was determined using acute dermal irritation test (OECD 404), while the efficacy was assessed using an in vitro pediculicidal assay. Furthermore, the chemical compounds present in T. crispa were identified using liquid-liquid extraction followed by ultra-performance liquid chromatography quadruple time-of-flight mass spectrometric (UPLC-qTOF/MS) analysis. The community-based ointment formulation was light yellow in color, homogeneous, smooth, with distinct aromatic odor and pH of $6.92{\pm}0.09$. It has spreadability value of $15.04{\pm}0.98g{\cdot}cm/sec$ and has thixotropic behavior. It was also found to be non-irritant, with a primary irritation index value of 0.15. Moreover, it was comparable to the pediculicidal activity of the positive control $Kwell^{(R)}$, a commercially available 1% permethrin shampoo (P>0.05), and was significantly different to the activity of the negative control ointment, a mixture of palm oil and candle wax (P<0.05). These findings suggested that the community-based T. crispa pediculicidal ointment is safe and effective, having acceptable physicochemical characteristics. Its activity can be attributed to the presence of compounds moupinamide and physalin I.

• 한국자기공명학회논문지
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• 제15권1호
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• pp.69-79
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• 2011

HP0827 has two RNP motif which is a very common protein domain involved in recognition of a wide range of ssRNA/DNA.We acquired 3D NMR spectra of HP0827 which shows well dispersed and homogeneous signals which allows us to assign 98% of all $^1H_N$, $^{15}N$, $^{13}C_{\alpha}$, $^{13}C_{\beta}$ and $^{13}C$=O resonances and 90% of all sidechain resonances. The sequence-specific backbone resonance assignment of HP0827 can be used to gain deeper insights into the nucleic acids binding specificity of HP0827 in the future study. Here, we report secondary structure prediction of HP0827 derived from NMR data. Additionally, ssRNA/DNA binding assay studies was also conducted. This study might provide a clue for exact function of HP0827 based on structure and sequence.

• 대한의생명과학회지
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• 제22권4호
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• pp.160-166
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• 2016

To provide a basis for a homogeneous fluorescence resonance energy transfer (FRET) immunoassay for celiac disease, we carried out a FRET experiment using guinea pig tissue transglutaminase (tTG) and antibodies to tTG (anti-tTG) purified from rat serum. Fluorescein was utilized as the probe, and a nonfluorescent dye, QSY 7 served as the quencher. We labeled anti-tTG and tTG with fluorescein isothiocyanate and QSY 7 succinimidyl ester, respectively. Fluorescein-labeled anti-tTG was the donor, and QSY 7-labeled tTG was the acceptor of the FRET experiment. When we titrated fluorescein-labeled anti-tTG with QSY 7-labeled tTG, we observed a large decrease in the steady-state fluorescence intensity, which was due to strong FRET from fluorescein-labeled anti-tTG to QSY 7-labeled tTG. Using time-resolved fluorescence spectroscopy, we could also observe a decrease in the fluorescence lifetime, which confirms the steady-state data. We expect that these results might be useful in the development of a novel fluorescence immunoassay for an easy screening and follow-up of celiac patients.

• The Plant Pathology Journal
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• 제20권4호
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• pp.283-288
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• 2004

Four Erwinia carotovora strains isolated from potatoes showing blackleg symptoms and rotted Chinese cabbage were analysed by biochemical tests and sequence analysis of 16S rDNA and 16S-23S rRNA intergenic spacer (IGS) regions, and the data were compared to related E. carotovora strains. Based on the results of the biochemical tests and sequence analysis, 2 of the 4 strains were identified as E. carotovora subsp. carotovora (Ecc), whereas the rest strains were distinct from Ecc. The last two strains, HCC3 and JEJU, were biochemically similar to E, carotovora subsp. atroseptica (Eca). However, the results of sequence analysis and Eca-specific PCR assays showed that the strains were distinct from Eca. On the basis of 16S rDNA sequence analysis, HCC3 and JEJU strains were placed in E. carotovora subsp. odorifera and E. carotovora subsp. wasabiae, respectively. The results of sequence analysis and specific PCR assay for Eca indicated that Asian Eca strains were distinct from European Eca strains, although they were phenotycally homogeneous.