• Food Science and Biotechnology
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• 제18권5호
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• pp.1150-1154
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• 2009

Low levels of virus contamination and naturally occurring reverse transcription-polymerase chain reaction (RT-PCR) inhibitors restrain virus detection in oysters. A rapid and efficient oyster-processing procedure that can be used for sensitive virus detection in oysters was developed. Poliovirus type 1 Sabin strain was used to evaluate the efficacy of virus recovery. The procedure included (a) acid-adsorption and elution with buffers (0.25M glycine-0.14 M NaCl, pH 7.5; 0.25M threonine-0.14M NaCl, pH 7.5); (b) polyethylene glycol (PEG) precipitation; (c) resuspension in Tween 80/Tris solution and chloroform extraction; (d) the second PEG precipitation; (e) viral RNA extraction with TRIzol and isopropanol precipitation; and (f) RT-PCR combined with semi-nested PCR. The overall recovery of elution/concentration was 19.5% with poliovirus. The whole procedure usually takes 19 hr. The overall detection sensitivity was 4 RT-PCR units of genogroup I norovirus (NoV) and 6.4 RT-PCR units of genogroup II Nov/25 g of oysters initially seeded. The virus-detecting method developed in this study should facilitate the detection of low levels of NoV in oysters.

• Preventive Nutrition and Food Science
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• 제2권3호
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• pp.197-201
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• 1997

To develop a rapid analytical method of dimethylamine(DMA) and trimethylamine(TMA) in fish, the contents of DMA and TMA in squid(Illex illecebrosus and Sepiell maindroni), cod(Gadus marcrocephalus) and plaice (Paralichthys olivaceus) by gas chromatographic (GC) and colorimetric method were determined. Recoveries for DMA in fish were 86.8~102.5% by GC and 74.2~94.5% by colorimetric method, while those for TMA were 93.0~101.1% by GC and 62.9~117.5% by colorimetric method. The contents of DMA and TMA in fish by GC were 29.7~325.3mg/kg and 145.6~356.0 mg/kg, respectively, and these by colorimetric method were 20.0~241.2mg/kg and 139.1~304.3mg/kg, respectively. The analysis of DMA and TMA in fishes by GC after the solvent extraction was simpler and faster and showed better recovery than colorimetric method.

• Bulletin of the Korean Chemical Society
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• 제32권5호
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• pp.1547-1553
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• 2011

An effective analytical method of gas chromatography/mass spectrometry (GC/MS) was developed for the rapid determination of essential oils in the crude extract of Acorus species (Acorus gramineus, Acorus tatarinowii, and Acorus calamus). Major phenypropanoids (${\beta}$,${\alpha}$-asarone isomers, euasarone, and methyleugenol) and ${\beta}$-caryophyllene in Acorus species were used as marker compounds and determined for the quality control of herbal medicines. To extract marker compounds, various extraction techniques such as solvent immersion, mechanical shaking, and sonication were compared, and the greatest efficiency was observed with sonication extraction using petroleum ether. The dynamic range of the GC/MS method depended on the specific analyte; acceptable quantification was obtained between 10 and 2000 ${\mu}g/mL$ for ${\beta}$-asarone, 10 and 500 ${\mu}g/mL$ for ${\alpha}$-asarone, 10 and 200 ${\mu}g/mL$ for methyleugenol, and between 5 and 100 ${\mu}g/mL$ for ${\beta}$-caryophyllene. The method was deemed satisfactory by inter- and intra-day validation and exhibited both high accuracy and precision, with a relative standard deviation < 10%. Overall limits of detection were approximately 0.34-0.83 ${\mu}g/mL$, with a standard deviation (${\sigma}$)-to-calibration slope (s) ratio (${\sigma}$/s) of 3. The limit of quantitation in our experiments was approximately 1.13-3.20 ${\mu}g/mL$ at a ${\sigma}$/s of 10. On the basement of method validation, 20 samples of Acorus species collected from markets in Korea were monitored for the quality control. In addition, principal component analysis (PCA) and hierarchical cluster analysis (HCA) were performed on the analytical data of 20 different Acorus species samples in order to classify samples that were collected from different regions.

• 분석과학
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• 제31권2호
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• pp.65-70
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• 2018

이 연구에서는 대규모 병렬형 염기서열 분석 (massively parallel sequencing)에 적용할 샷건 라이브러리 (shotgun library)를 성공적으로 제작하기 위해 두 가지 유형의 고대 DNA (ancient DNA, aDNA) 분리 방법을 비교하였다. 헝가리 선사 시대 늑골 뼈 시료로 실리카 현탁액을 이용한 추출법과 Amicon Ultracel-15 10K 초원심 분리 장치(Millipore)를 이용한 추출법을 비교하였다. 약 150 mg의 뼛가루에서 각각의 방법으로 3 회 반복 추출한 후 이중 가닥 DNA (double stranded DNA, ds DNA)의 양을 측정하였다. 초원심분리 농축 방법은 실리카 현탁액을 사용하는 것보다 더 빠르고, 더 쉬운 공정이며 약 11 배 높은 DNA 회수율을 나타냈다. 또한 초원심 분리 장치로 획득한 DNA 주형은 실리카 현탁액으로 획득한 것보다 샷건 라이브러리가 훨씬 성공적으로 만들어졌다. 두 종류의 aDNA 추출 방법을 비교한 본 연구는 Amicon 장치를 사용하는 분리법이 시간의 절약, 단순한 프로세스 및 높은 효율 등의 장점을 지니고 있음을 보여주었다.

• Journal of Microbiology and Biotechnology
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• 제24권6호
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• pp.732-739
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• 2014

We describe the development of a polymerase chain reaction method for the rapid, precise, and specific detection of the Xanthomonas oryzae pv. oryzae (Xoo) K3a race, the bacterial blight pathogen of rice. The specific primer set was designed to amplify a genomic locus derived from an amplified fragment length polymorphism specific for the K3a race. The 1,024 bp amplicon was generated from the DNA of 13 isolates of Xoo K3a races out of 119 isolates of other races, pathovars, and Xanthomonas species. The assay does not require isolated bacterial cells or DNA extraction. Moreover, the pathogen was quickly detected in rice leaf 2 days after inoculation with bacteria and at a distance of 8 cm from the rice leaf 5 days later. The results suggest that this PCR-based assay will be a useful and powerful tool for the detection and identification of the Xoo K3a race in rice plants as well as for early diagnosis of infection in paddy fields.

• Journal of Pharmaceutical Investigation
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• 제39권5호
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• pp.367-372
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• 2009

A rapid liquid chromatography/tandem mass spectrometry (LC/MS/MS) assay method was developed for the determination of topotecan levels in rat serum. The assay utilized a single liquid-liquid extraction with a mixture of ethy l acetate and acetonitrile (6:1 v/v) and isocratic elution. The multiple reaction monitoring was based on the transition of m/z 422.0$\rightarrow$376.5 for topotecan and 315.1$\rightarrow$226.6 for clomipramine (internal standard). The developed assay was validated to demonstrate the specificity, recovery, lower limit of quantification (LLOQ), accuracy and precision. The assay was linear over a concentration range from 0.5-100 ng/mL, with LLOQ being 0.5 ng/mL using a small volume of rat serum (0.1 mL). The mean intra- and inter-day assay accuracy was 87.7-111.0% and 97.8-108.3, respectively, and the mean intra- and interday precision was between 1.6-4.3% and 3.8-10.3, respectively. The developed assay was applied to a pharmacokinetic study after a bolus i.v. injection of topotecan in rats.

• 대한치과교정학회지
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• 제49권2호
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• pp.89-96
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• 2019

Objective: The purpose of this study was to assess the long-term stability of rapid palatal expansion (RPE) followed by full fixed edgewise appliances. Methods: This study included 67 patients treated using Haas-type RPE and non-extraction edgewise appliance therapy at a single orthodontic practice. Serial dental casts were obtained at three different time points: pretreatment ($T_1$), after expansion and fixed appliance therapy ($T_2$), and at long-term recall ($T_3$). The mean duration of the $T_1-T_2$ and $T_2-T_3$ periods was $4.8{\pm}3.5years$ and $11.0{\pm}5.4years$, respectively. The dental casts were digitized, and the computed measurements were compared with untreated reference data. Results: The majority of treatment-related increases in the maxillary and mandibular arch measurements were statistically significant (p < 0.05) and greater than expected for the untreated controls. Although many measurements decreased postretention ($T_2-T_3$), the net gains persisted for all of the measurements evaluated. Conclusions: The use of RPE therapy followed by full fixed edgewise appliances is an effective method for increasing maxillary and mandibular arch width dimensions in growing patients.

• 식물병연구
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• 제21권3호
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• pp.180-185
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• 2015

In the present work, a pair of primers specific to Tomato yellow leaf curl virus (TYLCV) was designed to allow specific amplification of DNA fragments from any TYLCV isolates using an extensive alignment of the complete genome sequences of TYLCV isolates deposited in the GenBank database. A pair of primers which allows the specific amplification of tomato ${\beta}$-tubulin gene was also analyzed as an internal PCR control. A duplex PCR method with the developed primer sets showed that TYLCV could be directly detected from the leaf crude sap of infected tomato plants. In addition, our developed duplex PCR method could determine PCR errors for TYLCV diagnosis, suggesting that this duplex PCR method with the primer sets is a good tool for specific and sensitive TYLCV diagnosis. The developed duplex PCR method was further verified from tomato samples collected from some farms in Korea, suggesting that this developed PCR method is a simple and reliable tool for rapid and large-scale TYLCV detections in tomato plants.

• Animal cells and systems
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• 제3권1호
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• pp.73-78
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• 1999

Although there are several methods for the preparation of mitochondrial DNA (mtDNA) from mammalian tissues, most are relatively long ultracentrifugation or manipulations by a small-scale method. We escribed a rapid method for large-scale extraction of mtDNA from human placental and horse liver tissues. The method is based on the preparation and homogenization of tissues, urification of crude mitochondria by differential centrifugations and isolation of mtDNA by alkaline Iysis. It was improved from Pre-existing methods by replacing some steps with simpler ones and discarding many others. This method gives a high yield of pure mtDNA(approximately 1-5mg from one placenta; ca. 400-600 g wet weight), depending on its sources (fresh tissue gave better results than frozen one). The resulting mtDNA indicated that this method can yield mtDNA in sufficient purity and quantity to identify the direct restriction analysis on agarose gel, random-primed labeling as a probe, and end labeling. Therefore, the method is ideal for obtaining good mtDNA samples to conduct routine restriction fragment length polymorphism (RFLP) analyses of natural populations for genetic studies.

• Smart Structures and Systems
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• 제33권6호
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• pp.449-463
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• 2024

Automated crack detection is crucial for structural health monitoring and post-earthquake rapid damage detection. However, realizing high precision automatic crack detection in the absence of corresponding manual labeling presents a formidable challenge. This paper presents a novel crack segmentation transfer learning method and a novel crack segmentation model called Swin-CrackFormer. The proposed method facilitates efficient crack image style transfer through a meticulously designed data preprocessing technique, followed by the utilization of a GAN model for image style transfer. Moreover, the proposed Swin-CrackFormer combines the advantages of Transformer and convolution operations to achieve effective local and global feature extraction. To verify the effectiveness of the proposed method, this study validates the proposed method on three unlabeled crack datasets and evaluates the Swin-CrackFormer model on the METU dataset. Experimental results demonstrate that the crack transfer learning method significantly improves the crack segmentation performance on unlabeled crack datasets. Moreover, the Swin-CrackFormer model achieved the best detection result on the METU dataset, surpassing existing crack segmentation models.