• Applied Microscopy
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• 제51권
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• pp.4.1-4.12
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• 2021

Fluorescence in situ hybridization (FISH) is a technique to visualize specific DNA/RNA sequences within the cell nuclei and provide the presence, location and structural integrity of genes on chromosomes. A confocal Whole Slide Imaging (WSI) scanner technology has superior depth resolution compared to wide-field fluorescence imaging. Confocal WSI has the ability to perform serial optical sections with specimen imaging, which is critical for 3D tissue reconstruction for volumetric spatial analysis. The standard clinical manual scoring for FISH is labor-intensive, time-consuming and subjective. Application of multi-gene FISH analysis alongside 3D imaging, significantly increase the level of complexity required for an accurate 3D analysis. Therefore, the purpose of this study is to establish automated 3D FISH scoring for z-stack images from confocal WSI scanner. The algorithm and the application we developed, SHIMARIS PAFQ, successfully employs 3D calculations for clear individual cell nuclei segmentation, gene signals detection and distribution of break-apart probes signal patterns, including standard break-apart, and variant patterns due to truncation, and deletion, etc. The analysis was accurate and precise when compared with ground truth clinical manual counting and scoring reported in ten lymphoma and solid tumors cases. The algorithm and the application we developed, SHIMARIS PAFQ, is objective and more efficient than the conventional procedure. It enables the automated counting of more nuclei, precisely detecting additional abnormal signal variations in nuclei patterns and analyzes gigabyte multi-layer stacking imaging data of tissue samples from patients. Currently, we are developing a deep learning algorithm for automated tumor area detection to be integrated with SHIMARIS PAFQ.

• 대한치과의사협회지
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• 제56권1호
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• pp.8-16
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• 2018

Purpose: The aim of in vitro study was to compare the diagnostic accuracy to detect non-cavitated enamel caries on smooth surface by using four kinds of the QLF devices. Materials and Methods: A total of 52 human permanent premolars and molars were used. Fluorescence images were captured by the QLF devices (Inspektor Pro, QLF-D, Qraycam, and Qraypen). Fluorescence loss of the QLF was calculated. The severity of lesions was categorized into the following 3 scores using polarized light microscopy: normal (S), enamel demineralization to outer half of enamel (D1), and inner half of the enamel up to the dentin-enamel junction (D2). The Kruskal-Wallis test was used to compare the fluorescence loss among the QLF devices. Spearman rank correlation coefficient between histological scores and fluorescence loss of the devices was calculated. The sensitivity, specificity, and area under the receiver operating curve (AUROC) were calculated to compare their diagnostic accuracies. Results: The correlation coefficients between histological scores and the fluorescence loss of the devices showed 0.77 to 0.81 (P < 0.001). All histological scores, the fluorescence loss among the devices showed no statistical difference. Among the devices, sensitivity, specificity, and AUC values of the fluorescence loss showed 0.84 to 0.94, 0.76 to 0.90, and 0.90 to 0.92, respectively. Conclusions: All QLF devices had no difference with excellent diagnostic accuracies to detect non-cavitated enamel caries on smooth surface.

• 식물병연구
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• 제7권2호
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• pp.116-119
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• 2001

Witches' broom symptoms were firstly found on tubers of Solanum tuberosum cv, Deijima, showing dense growth of spindly sprouts in Cheju province, Korea. Plantlets from the diseased plants also produced the typical witches' broom symptoms, having densely-growing small leaves when they became adult plants. At the later stages the diseased leaves were blightened. Presence of phytoplasma in plant tissues was confirmed by DAPI-staining fluorescence microscopy and electron microscopy, exhibiting its localization in sieve tubes of stem, petiole, and midrib. This is the first report of potato witches' broom in Korea.

• 접착 및 계면
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• 제1권1호
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• pp.47-55
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• 2000

In this article, the characterization of the interface of hybrid composites was discussed. Interfacial interaction in organic/inorganic hybrid composites, especially silica-containing hybrids can be characterized by fluorescence spectroscopy, small angle X-ray scattering (SAXS), scanning electron microscopy (SEM), atomic force microscopy (AFM), and $^{29}Si$ NMR spectroscopy measurements.

• 대한소아치과학회지
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• 제34권2호
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• pp.183-191
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• 2007

본 연구는 Digital Imaging Fiber-Optic Trans-Illumination(DIFOTI)이나 Laser Fluorescence(LF)를 이용한 방법이 평활면 법랑질 초기우식증의 재광화 정도를 정확하게 monitoring 할 수 있는지의 여부를 평가하기 위하여 진행되었다. 우치 법랑질로부터 얻어진 인공 우식 절편을 특별히 제작된 의치에 식립한 다음, 10명의 실험 참가자들이 구강 내에 장착하고 3주 동안 불소 양치용액을 사용하도록 한 다음 Confocal Laser Scanning Microscopy(CLSM)로 측정된 병소 깊이를 gold standard로 사용하여 DIFOTI와 LF로 측정 된 우식 절편의 재광화 정도를 비교 평가한 후 다음과 같은 결론을 얻었다. 1. DIFOTI에 측정된 광도 백분율이 재광화 기간이 지남에 따라 증가하였으며, CLSM에서 측정된 병소 깊이와 유의한 역상관관계를 보였다(r=-0.683, p<0.01). 2. LF 측정치는 재광화 기간이 경과함에 따라 증가하였으며 CLSM에서 측정된 병소 깊이와 유의한 상관관계를 보였다(p<0.05). 3. CLSM 촬영 결과 500 ppm 불소 양치군이 0 ppm 불소 양치군보다 빠른 속도로 병소 깊이가 감소하는 양상을 보여 주었다.

• Applied Microscopy
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• 제48권4호
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• pp.96-101
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• 2018

The release of nanoscale membrane-bound vesicles is common in all three domains of life. These vesicles are involved in a variety of biological processes such as cell-to-cell communication, horizontal gene transfer, and substrate transport. Prokaryotes including bacteria and archaea release membrane vesicles (MVs) (20 to 400 nm in diameter) into their extracellular milieu. In spite of structural differences in cell envelope, both Gram-positive and negative bacteria produce MVs that contain the cell membrane of each bacterial species. Archaeal MVs characteristically show surface-layer encircling the vesicles. Filamentous fungi and yeasts as eukaryotic microbes produce bilayered exosomes that have varying electron density. Microbes also form intracellular vesicles and minicells that are similar to MVs and exosomes in shape. Electron and fluorescence microscopy could reveal the presence of DNA in MVs and exosomes. Given the biogenesis of extracellular vesicles from the donor cell, in situ high-resolution microscopy can provide insights on the structural mechanisms underlying the formation and release of microbial extracellular vesicles.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2002년도 총회 및 추계학술발표회
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• pp.68.2-69
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• 2002

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2000년도 추계 학술발표회
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• pp.49.2-49
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• 2000

• BMB Reports
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• 제35권6호
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• pp.562-567
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• 2002

In order to find the cellular interaction factors of the Heliothis armigera nuclear polyhedrosis virus capsid protein VP39, a Heliothis armigera cell cDNA library was constructed. Then VP39 was used as bait. The host actin gene was isolated from the cDNA library with the yeast two-hybrid system. This demonstrated that VP39 could interact with its host actin in yeast. In order to corroborate this interaction in vivo, the vp39 gene was fused with the green fluorescent protein gene in plasmid pEGFP39. The fusion protein was expressed in the Hz-AM1 cells under the control of the Autographa californica multiple nucleopolyhedrovirus immediate early gene promoter. The host actin was labeled specifically by the red fluorescence substance, tetramethy rhodamine isothicyanete-phalloidin. Observation under a fluorescence microscopy showed that VP39, which was indicated by green fluorescence, began to appear in the cells 6 h after being transfected with pEGFP39. Red actin cables were also formed in the cytoplasm at the same time. Actin was aggregated in the nucleus 9 h after the transfection. The green and red fluorescence always appeared in the same location of the cells, which demonstrated that VP39 could combine with the host actin. Such a combination would result in the actin skeleton rearrangement.

• BMB Reports
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• 제54권3호
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• pp.157-163
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• 2021

The transient interactions between cellular components, particularly on membrane surfaces, are critical in the proper function of many biochemical reactions. For example, many signaling pathways involve dimerization, oligomerization, or other types of clustering of signaling proteins as a key step in the signaling cascade. However, it is often experimentally challenging to directly observe and characterize the molecular mechanisms such interactions-the greatest difficulty lies in the fact that living cells have an unknown number of background processes that may or may not participate in the molecular process of interest, and as a consequence, it is usually impossible to definitively correlate an observation to a well-defined cellular mechanism. One of the experimental methods that can quantitatively capture these interactions is through membrane reconstitution, whereby a lipid bilayer is fabricated to mimic the membrane environment, and the biological components of interest are systematically introduced, without unknown background processes. This configuration allows the extensive use of fluorescence techniques, particularly fluorescence fluctuation spectroscopy and single-molecule fluorescence microscopy. In this review, we describe how the equilibrium diffusion of two proteins, K-Ras4B and the PH domain of Bruton's tyrosine kinase (Btk), on fluid lipid membranes can be used to determine the kinetics of homodimerization reactions.