• The Korean Journal of Mycology
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• v.27 no.2 s.89
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• pp.132-137
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• 1999

This study was carried out to develop the molecular marker for the detection of Pseudomonas tolaasii, a causative agent of bacterial brown blotch disease of oyster mushroom (Pleurotus ostreatus). When several primers designed from repetitive sequences and pectin lyase genes of bacteria were used to produce DNA polymorphism from different Pseudomonas spp. isolated from edible mushrooms, PEU1 primer derived from pectin lyase gene produced polymorphic bands differentiating P. tolaasii strains from other Pseudomonas species. Two bands, 1.0kb and 0.4kb, found commonly in 6 isolates of P. tolaasii were cloned into pGEM-T vector which were designated as pPTOP1 and pPTOP2, respectively, to use as probe. The 0.4 kb insert of pPTOP2 hybridized to only 6 isolates of P. tolaasii, but did not to the other Pseudomonas species. As few as $1.5{\times}10^3$ colony forming unit (cfu) of P. tolaasii could be detected by dot blot hybridization with the cloned 0.4kb DNA in pPTOP2.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.530-537
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• 2004

Development of a versatile nanomanipulation tool is an overarching theme in nanotechnology. Such a tool will likely revolutionize the field given that it will enable fabrication and operation of a wealth of interesting nanodevices. This study seeks funding to create a novel nanomanipulation system with the ultimate goal of using this system for nanomanufacturing at the molecular level. The proposed design differs from existing approaches. It is based on a nanoscale ion trap integrated to a scanning prove microscope (SPM) tip. In this design, molecules to be assembled will be ionized and collected in the nanoscale ion trap all in an ultra high vacuum (UHV) environment. Once filled with the molecular ions, the nanoscale ion trap-SPM tip will be moved on a substrate surface using scanning probe microscopy techniques. The molecular ions will be placed at their precise locations on the surface. By virtue of the SPM, the devices that are being nanomanufactured will be imaged in real time as the molecular assembly process is carried out. In the later stages, automation of arrays of these nanomanipulators will be developed.

• Bulletin of the Korean Chemical Society
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• v.32 no.spc8
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• pp.2928-2932
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• 2011

A chemosensor based on a rhodamine-hydroxamate platform containing a pyridine and a cyclen binding units has been developed for the detection of $Cd^{2+}$ in aqueous solutions. The probe responds selectively toward $Cd^{2+}$ over other biologically relevant metal ions. The fluorescent probe shows 1:1 binding stoichiometry and the detection limit for $Cd^{2+}$ in water proved to be as low as 25 nM.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.6 no.2
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• pp.177-181
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• 2020

Dual-modality imaging strategy using near-infrared fluorescence (FLI) and photoacoustic imaging (PAI) demands a suitable probe to enable dual-modular signal production. Herein, we demonstrate a synthetic protocol of small molecular dye for dual-modular FLI and PAI. A condensation reaction between squaric acid and carboxypentyl benzoindolium, and followed by basic hydrolysis to give the benzoindole derived squaraine (BSQ) dye in 49% yield. Next, the carboxylic acid group of BSQ was further functionalized with N-hydroxysuccinimide or azide group for an efficient conjugation with a targeting biomolecule. BSQ showed a maximum fluorescent emission at around 680 nm and the photoacoustic signal reached a maximum intensity at 680-700 nm. Based on these results, we conclude that BSQ analogs will be useful probes for dual-modular (FLI/PAI) imaging studies in animal models.

• Proceedings of the Botanical Society of Korea Conference
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• 1987.07a
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• pp.323-347
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• 1987

The R locus of maize in one of several genes that regulate the anthocyanin pigments throughout the body of the plant and seed. The R gene product may regulate pigment deposition by controlling the expression of the flavonoid biosynthetic gene pathway in a tissue-specific manner. To understand the basis for tissue specific regulation and allelic variation at R, the molecular study has been done by cloning a portion of the R complex by transposon tagging with Ac. R specific probe were cloned from the R-nj mutant induced by Ac insertion mutagenesis. From southern analysis of R-r complex using the R-nj probe, the structure of R-r was proposed that R-r containes the three elements, (P)(Q)(S). These elements may organize as the inversion triplication model which (S) sequence was inverted in relation to (P) and (Q). The R-sc derivated from R-mb or R-nj was cloned with R-nj probe, and molecular genetical data showed that R-sc containes tissue specific and tissue nonspecific area, and the sequencing of R-sc are progressed now.

• The Korean Journal of Nuclear Medicine
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• v.38 no.2
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• pp.121-130
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• 2004

Molecular imaging visualizes cellular processes at a molecular or genetic level in living subjects, and diverse molecular probes are used for this purpose. Radiolabeling methods as well as radioisotopes are very important in preparation of molecular probes, because they can affect the biodistribution in tissues and the excretion route. In this review, the molecular probes are divided into small organic molecules and macromolecules such as peptides and proteins, and their commonly used radiolabeling methods are described.

• Macromolecular Research
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• v.12 no.3
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• pp.282-289
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• 2004

We have extensively characterized the fluorescence behavior of unsaturated polyester (UP) resin in the absence and presence of a 1,3-bis-(l-pyrenyl)propane (BPP) fluorescent probe at various dynamic and isothermal cure histories by means of a steady-state fluorescence technique using a front-face illumination equipment. In addition, we explored the effect of the fluorescence intensity on the relaxation of the fluorescent probe in the UP resin by resting the dynamically and isothermally cured resin at ambient temperature and pressure for 24 h. The monomer fluorescence intensity, which has two characteristic peaks at 376 and 396nm, changed noticeably depending on the cure temperature and time and provided important information with respect to the molecular and photophysical responses upon curing. The result of the fluorescence study indicates that the increased local viscosity and restricted molecular mobility of the UP resin surrounding the BPP probe after curing are both responsible for the enhancement of the monomer fluorescence intensity. Our results also demonstrate that once the BPP probe has enough time to rearrange and become isolated prior to fluorescence, a sufficient amount of fluorescence is emitted. Therefore, we note that the fluorescence behavior of this UP resin system is influenced strongly by the relaxation process of the fluorescent probe in the resin as well as process used to cure the resin.

• Journal of Radiopharmaceuticals and Molecular Probes
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• v.4 no.1
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• pp.3-10
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• 2018

The folate receptor (FR) is a promising cell membrane-associated target for nuclear imaging of various cancers (via imaging $FR-{\alpha}$) and potentially also inflammatory diseases (via imaging $FR-{\beta}$), through the use of folic acid-based radioconjugates. However, there have been several drawbacks of previously reported radioconjugates, such as a short half-life of the radiolabel ($^{68}Ga\;t_{1/2}$ 68 min), a complex and time-consuming multistep radiosynthesis, and a high renal uptake of radiolabeled folate derivatives. The goal of this study was to develop an imaging probe by directly labeling folate with radioactive iodine without using an extra prosthetic group. The radiolabeling of folate was optimized using various labeling conditions and the labeled tracers were isolated by high-performance liquid chromatography. The in vitro stability of labeled folate was checked in phosphate-buffered saline and serum. The tumor-targeting efficacy of the probe was also evaluated by biodistribution studies using a murine 4T1 tumor model.

• Genomics & Informatics
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• v.5 no.2
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• pp.46-55
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• 2007

The convergence of molecular and genetic disciplines with non-invasive imaging technologies has provided an opportunity for earlier detection of disease processes which begin with molecular and cellular abnormalities. This emerging field, known as molecular imaging, is a relatively new discipline that has been rapidly developed over the past decade. It endeavors to construct a visual representation, characterization, and quantification of biological processes at the molecular and cellular level within living organisms. One of the goals of molecular imaging is to translate our expanding knowledge of molecular biology and genomic sciences into good patient care. The practice of molecular imaging is still largely experimental, and only limited clinical success has been achieved. However, it is anticipated that molecular imaging will move increasingly out of the research laboratory and into the clinic over the next decade. Non-invasive in vivo molecular imaging makes use of nuclear, magnetic resonance, and in vivo optical imaging systems. Recently, an interest in Positron Emission Tomography (PET) has been revived, and along with optical imaging systems PET is assuming new, important roles in molecular genetic imaging studies. Current PET molecular imaging strategies mostly rely on the detection of probe accumulation directly related to the physiology or the level of reporter gene expression. PET imaging of both endogenous and exogenous gene expression can be achieved in animals using reporter constructs and radio-labeled probes. As increasing numbers of genetic markers become available for imaging targets, it is anticipated that a better understanding of genomics will contribute to the advancement of the molecular genetic imaging field. In this report, the principles of non-invasive molecular genetic imaging, its applications and future directions are discussed.

• Fisheries and Aquatic Sciences
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• v.7 no.4
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• pp.175-183
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• 2004

The dinoflagellate Alexandrium tamiyavanichii Balech, a producer of toxins causing paralytic shellfish poisoning (PSP), has recently been considered as one of main organisms responsible for toxication of shellfish in Japan. In this study, A. tamiyavanichii was subjected to a molecular phylogenetic analysis inferred from 28S rDNA D1-D2 sequences and a species-specific LSU rRNA-targeted oligonucleotide DNA probe was designed to identify A. tamiyavanichii using the whole cell-FISH (fluorescence in situ hybridization). The sequences of the 28S rDNA D1-D2 region of A. tamiyavanichii showed no difference from A. cohorticular AF1746l4 (present name A. tamiyavanichii) and formed a distinct clade from the 'tamarensis species complex'. The probe, TAMID2, reacted specifically with A. tamiyavanichii cultured cells, without any cross-reaction with other species belonging to the same genus, including A. tamarense, A. catenella, A. affine, A. fraterculus, A. insuetum and A. pseudogonyaulax. In a test of cross-reactivity with a field sample, TAMID2 reacted consistently with only A. tamiyavanichii, indicating that the present protocol involving the TAMID2 probe might be useful for detecting toxic A. tamiyavanichii in a simple and rapid manner.