• Nuclear Medicine and Molecular Imaging
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• v.43 no.4
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• pp.363-365
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• 2009

Kikuchi's disease is a self-limiting benign disease characterized by cervical lymphadenopathy, but it can be mistaken for malignant disease, and when involved lymph nodes are unusually located, diagnosis can be more difficult. The authors report the case of a 19-year-old man with Kikuchi's disease, who had isolated intra-abdominal lymphadenopathy and increased 18-fluoro-deoxyglucose (FDG) uptake in positron emission tomography-computed tomography (PET-CT). Although its incidence is extremely rare, intra-abdominal Kikuchi's disease with increased FDG uptake in PET-CT image should be considered in the differential diagnosis when constitutional symptoms mimic those of malignant lymphoma.

• Nuclear Engineering and Technology
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• v.43 no.6
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• pp.477-488
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• 2011

A formulation is proposed for modelling the process of intra-granular diffusion of fission gas during irradiation of $UO_2$ under both normal operating conditions and power transients. The concept represents a simple extension of the formulation of Speight, including an estimation of the contribution of bubble motion to fission gas diffusion. The resulting equation is formally identical to the diffusion equation adopted in most models that are based on the formulation of Speight, therefore retaining the advantages in terms of simplicity of the mathematical-numerical treatment and allowing application in integral fuel performance codes. The development of the new model proposed here relies on results obtained by means of molecular dynamics simulations as well as finite element computations. The formulation is proposed for incorporation in the TRANSURANUS fuel performance code.

• Molecules and Cells
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• v.19 no.1
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• pp.104-113
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• 2005

Large inversions are well characterized in the chloroplast genomes of land plants. In contrast, reports of small inversions are rare and involve limited plant groups. In this study, we report the widespread occurrence of small inversions ranging from 5 to 50 bp in fully and partially sequenced chloroplast genomes of both monocots and dicots. We found that small inversions were much more common than large inversions. The small inversions were scattered over the chloroplast genome including the IR, SSC, and LSC regions. Several small inversions were uncovered in chloroplast genomes even though they shared the same overall gene order. The majority of these small inversions were located within 100 bp downstream of the 3' ends of genes. All had inverted repeat sequences, ranging from 11 to 24 bp, at their ends. Such small inversions form stem-loop hairpin structures that usually have the function of stabilizing the corresponding mRNA molecules. Intra-molecular recombination between the inverted sequences in the stem-forming regions are responsible for generating flip-flop orientations of the loops. The presence of two different orientations of the stem-loop in the trnL-F noncoding region of a single species of Jasminum elegans suggests that a short inversion can be generated within a short period of time. Small inversions of non-coding sequences may influence sequence alignment and character interpretation in phylogeny reconstructions, as shown in nine species of Jasminum. Many small inversions may have been generated by parallel or back mutation events during chloroplast genome evolution. Our data indicate that caution is needed when using chloroplast non-coding sequences for phylogenetic analysis.

• BMB Reports
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• v.41 no.12
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• pp.852-857
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• 2008

Little attention has been paid to the specificity between E2 and the target protein during ubiquitination, although RING-E3 induces a potential intra-molecular reaction by mediating the direct transfer of ubiquitin from E2 to the target protein. We have constructed artificial E2 fusion proteins in which a target protein (p27) is tethered to one of six E2s via a flexible linker. Interestingly, only three E2s (UbcH5b, hHR6b, and Cdc34) are able to ubiquitinate p27 via an intra-molecular reaction in this system. Although the first ubiquitination of p27 (p27-Ub) by Cdc34 is less efficient than that of UbcH5b and hHR6b, the additional ubiquitin attachment to p27-Ub by Cdc34 is highly efficient. The E2 core of Cdc34 provides specificity to p27, and the residues 184-196 are required for possessive ubiquitination by Cdc34. We demonstrate direct E2 specificity for p27 and also show that differential ubiquitin linkages can be dependent on E2 alone.

• Bulletin of the Korean Chemical Society
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• v.24 no.1
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• pp.55-59
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• 2003

This work is focused on analyzing ion-pair interactions and showing the effect of solvent induced inter-atomic attractions in various dielectric environments. To estimate the stability of ion-pairs, SCI-PCM ab initio MO calculations were carried out. We show that the solvent-induced attraction or ‘cavitation' energy of the ion-pair interactions in solution that arises mainly from the stabilization of the water molecules by the generation of an electrostatic field. In fact, even the strong electrostatic interaction characteristic of ion-pair interactions in the gas phase cannot overcome the destabilization or reorganization of the water molecules around solute cavities that arise from cancellation of the electrostatic field. The solvent environment, possibly supplemented by some specific solvent molecules, may help place the solute molecule in a cavity whose surroundings are characterized by an infinite polarizable dielectric medium. This behavior suggests that hydrophobic residues at a protein surface could easily contact the side chains of other nearby residues through the solvent environment, instead of by direct intra-molecular interactions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.7
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• pp.95-104
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• 2018

The structures and energies of the anhydrate and hydrate (hydrate rate: h of 1) states of L-alanine (LA) and glycine (G) were calculated by quantum chemical calculations (QCCs) using B3LYP/6-31G(d,p) for four types of conformers (${\beta}$-extended: ${\Phi}/{\Psi}=t-/t+$, $PP_{II}$: g-/t+, $PP_{II}$-like: g-/g+, and ${\alpha}$-helix: g-/g-). In LA and G, which have an imino proton (NH), three conformation types of ${\beta}$-extended, $PP_{II}$-like, and ${\alpha}$-helix were obtained, and water molecules were inserted mainly between the intra-molecular hydrogen bond of $CO{\cdots}HN$ in $PP_{II}$-like and ${\alpha}$-helix, and attached to the CO group in ${\beta}$-extended. In LA and G, $PP_{II}$-like conformers were most stable in the anhydrate and hydrate states, and the result for LA was different from some experimental and theoretical results from other studies reporting that the main stable conformation of alanine oligopeptide was $PP_{II}$. The formation pattern and stability of the conformation of the oligopeptide was strongly dominated by the presence/absence of intra-molecular hydrogen bonding of $CO{\cdots}HN$, or the presence/absence of an $NH_2$ group in the starting amino acid.

• Bulletin of the Korean Chemical Society
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• v.35 no.11
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• pp.3280-3288
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• 2014

Alkoxyalcohols are used as solvents or preservatives in various consumer products such as wet wipes. The metabolites of alkoxyalcohols are known to be chronically toxic and carcinogenic to animals. Thus, an analytical method is needed to monitor alkoxyalcohols in wet wipes. The aim of this study was to develop a simultaneous analytical method for 14 alkoxyalcohols using headspace gas chromatography coupled with mass spectrometry to analyze the wet wipes. This method was developed by comparing with various headspace extraction parameters. The linear calibration curves were obtained for the method ($r^2$ > 0.995). The limit of detection of alkoxyalcohols ranged from 2 to $200ng\;mL^{-1}$. The precision of the determinative method was less than 18.20% coefficient of variation both intra and inter days. The accuracy of the method ranged from 82.86% to 119.83%. (2-Methoxymethylethoxy)propanol, 2-phenoxyethanol, and 1-phenoxy-2-propanol were mainly detected in wet wipes.

• Korean Journal of Ecology and Environment
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• v.36 no.3 s.104
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• pp.221-234
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• 2003

Phylogenetic studies would clarify the diversity of fishes if the morphological analysis based on plesimorphy characters combined with new genetic analysis on molecular level, inferring more accurate and objective phylogeny and the taxonomy. Current molecular phylogenetic approach using mitochondrial genome provides the framework for a new hypothesis not only inferring the relationships between ancestor descendants but raveling the intra-, interspecies variation.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.117.2-117.2
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• 2011

We probe 12CO J=2-1 and 13CO J=1-0 properties of a Virgo disk galaxy, NGC 4402 which is located near the cluster center. Our goal is to study the impact of intra cluster medium (ICM) on the molecular gas of a galaxy in the cluster environment. It has been believed that cluster galaxies are deficient in atomic hydrogen gas (HI gas) compared to their field counterparts and now there is much evidence that low density ISM can be easily removed by ram pressure caused by ICM wind. Meanwhile, no significant molecular gas deficiency of the cluster galaxy population has been found yet they show overall lower star formation rate than galaxies in the field, and it is still controversy whether dense ISM can be also stripped by the ICM wind or not. NGC 4402 with truncated HI disk($D_{HI}/D_{opt}$ ~ 0.75 and only 36%of HI gas compare to field galaxies of a similar size) and a disturbed gas morphology, appears to have strong ongoing ram pressure. Using high resolution 12 and 13CO data of NGC 4402 from a Sub Millimeter Array (SMA), we probe the molecular gas properties under strong ICM pressure. We discuss how its star formation activity and hence the global color of NGC4402 would be changed in the future.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.879-883
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• 2005

This study was differentiated between Korea and China arkshells using PCR-aided RFLP method which could identify the variation for inter-and intra-species of arkshell (Scapharca broughtonii Schrenck) at the level of DNA. The DNA fragment patterns were compared after digesting gene of mitochondrial 16S rDNA with 8 kinds of restriction enzymes. A 720 bp DNA fragment corresponding to 16S rDNA gene was amplified by PCR with primers ArkF-3 and ArkR-3. PCR products were cut by restriction enzymes (Pvull, BamHI, Hinfl, HaeIII, EcoRI, RsaI, Ksp221, and BstX21), and RFLP pattern was studied. A unique 275 bp DNA band was observed in the samples from Dukyang, Gamak, Namhae, Jinhae, and Taean in Korea when treated by Hinfl, but Chinese arkshell did not show. Treatment of HaeIII could discriminate the sample of Namhae and Jinhae from Dukyang/Gamak/Taean, as well as Korean and Chinese arkshell based on a 700 bp. However, PuvII, BamHI, EcoRI, RsaI, Ksp221, and BstX21 showed the same of 700 bp band in Korean and Chinese arkshell. The phylogenetic tree inferred from PCR-RFLP pattern comparsion in Korean arkshell was different that the distance between Dukyang/Gamak/Taean and Namhae/Jinhae was approximately 7. In particular, the distance between Korean and Chinese arkshell was 25. Consequently, HinfI and HaeIII played an important role in a reliable molecular tool for rapid discriminating Korean and Chinese arkshell, as well as a intra-species in Korea.