• Journal of Biomedical Engineering Research
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• v.16 no.1
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• pp.9-16
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• 1995

Biodegradable poly (I ,4-butanediol succinate) (PBS) was synthesized from 1,4-butanediol and succinic anhydride. The glass transition temperature of poly (I, 4-butanediol succinate) was revealed at $73^{\circ}C$. The crystallization and cold crystallization of the polymers were investigated as a function of holding time in melt state, cooling rate. reheating, and molecular weight. Chain scission and/or cmsslinking did not occur in the melt state at var.ious holding times. Slower scanning rate can allow more times for nucleation, rearrangement, and packing of the polymer chain, so the onset temperature of crystallization from the melt was increased. PBS crystallized from the melt was found to have spherulitic structure. The degradation behavior of PBS was studied under basic conditions and with microorganisms using the modified ASTM method. In the basic solution. PBS lost up to 85% of its mass within two days. Based upon visual observation, the crystalline structure of films composed of larger molecular weight polymers retained their crystallinity longer than similar structures in low molecular weight samples.

• Journal of Biomedical Engineering Research
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• v.24 no.5
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• pp.447-451
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• 2003

A new method for analyzing the bone-remodeling process using quasi-molecular dynamics was proposed in this study. The effect of pressure due to bone marrow, which could not be considered in previous methods, was also considered in this method. Bone-remodeling response of the 2D vertebral body of lumbar spine to a uniaxial compressive displacement of 1.8564mm. corresponding to approximately 2kN of compressive load, was studied. Converged shape change of the cortical shell and rearrangement of cancellous bone structure matched well with a normal shape of the vertebral body. The calculated responses in the spinal elements also shows closed results compared with experimental results.

• Molecules and Cells
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• v.28 no.3
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• pp.155-165
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• 2009

The newly sequenced complete mitochondrial genome of the brown marmorated stink bug, Halyomorpha halys($St{\aa}l$) (Hemiptera: Pentatomidae), is a circular molecule of 16,518 bp with a total A+T content of 76.4% and two extensive repeat regions in A+T rich region. Nucleotide composition and codon usage of H. halys are about average when compared with values observed in 19 other published hemipteran mitochondrial genomes. Phylogenetic analyses using these 20 hemipteran mitochondrial genomes support the currently accepted hypothesis that suborders Heteroptera and Auchenorrhyncha form a monophyletic group. The mitochondrial gene arrangements of the 20 genomes are also consistent with our results.

• BMB Reports
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• v.42 no.9
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• pp.541-551
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• 2009

Amyloidogenesis defines a condition in which a soluble and innocuous protein turns to insoluble protein aggregates known as amyloid fibrils. This protein suprastructure derived via chemically specific molecular self-assembly process has been commonly observed in various neurodegenerative disorders such as Alzheimer's, Parkinson's, and Prion diseases. Although the major culprit for the cellular degeneration in the diseases remains unsettled, amyloidogenesis is considered to be etiologically involved. Recent recognition of fibrillar polymorphism observed mostly from in vitro amyloidogeneses may indicate that multiple mechanisms for the amyloid fibril formation would be operated. Nucleation-dependent fibrillation is the prevalent model for assessing the self-assembly process. Following thermodynamically unfavorable seed formation, monomeric polypeptides bind to the seeds by exerting structural adjustments to the template, which leads to accelerated amyloid fibril formation. In this review, we propose another in vitro model of amyloidogenesis named double-concerted fibrillation. Here, two consecutive assembly processes of monomers and subsequent oligomeric species are responsible for the amyloid fibril formation of $\alpha$-synuclein, a pathological component of Parkinson's disease, following structural rearrangement within the oligomers which then act as a growing unit for the fibrillation.

• Molecules and Cells
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• v.22 no.1
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• pp.78-88
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• 2006

The phylogeny of the subfamily Tephritinae (Diptera: Tephritidae) was reconstructed from mitochondrial 16S ribosomal RNA gene sequences using 53 species representing 11 currently recognized tribes of the Tephritinae and 10 outgroup species. The minimum evolution and Bayesian trees suggested the following phylogenetic relationships: (1) monophyly of the Tephritinae was strongly supported; (2) a sister group relationship between the Tephritinae and Plioreocepta was supported by the Bayesian tree; (3) the tribes Tephrellini, Myopitini, and Terelliini (excluding Neaspilota) were supported as monophyletic groups; (4) the non-monophyletic nature of the tribes Dithrycini, Eutretini, Noeetini, Tephritini, Cecidocharini, and Xyphosiini; and (5) recognition of 10 putative tribal groups, most of which were supported strongly by the statistical tests of the interior branches. Our results, therefore, convincingly suggest that an extensive rearrangement of the tribal classification of the Tephritinae is necessary. Since our sampling of taxa heavily relied on the current accepted classification, some lineages identified by the present study were severely under-sampled and other possible major lineages of the Tephritinae were probably not even represented in our dataset. We believe that our results provide baseline information for a more rigorous sampling of additional taxa representing all possible major lineages of the subfamily, which is essential for a comprehensive revision of the tephritine tribal classification.

• YAKHAK HOEJI
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• v.52 no.5
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• pp.412-417
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• 2008

BAY11-7082 was initially found to be an anti-inflammatory drug with NF-${\kappa}B$ inhibitory property. In this study, we evaluated modulatory function of BAY11-7082 on U937 cell-cell adhesion induced by CD29 (${\beta}1$-integrins). BAY11-7082 strongly blocked functional activation of CD29 (${\beta}1$-integrins), as assessed by cell-cell adhesion assay. However, this compound did not block a simple activation of CD29, as assessed by cell-fibronectin adhesion assay. In particular, to understand molecular mechanism of BAY11-7082-mediated inhibition, the regulatory roles of CD29-induced actin cytoskeleton rearrangement under cell-cell adhesion and surface level of CD29 were examined using confocal and flow cytometic analysis. Interestingly, this compound strongly suppressed the molecular association of actin cytoskeleton with CD29 at cell-cell adhesion site. Moreover, BAY11-7082 also diminished surface levels of CD29 as well as its-associated adhesion molecule CD147, but not other adhesion molecules such as CD18 and CD43. Therefore, our data suggest that BAY11-7082 may be involved in regulating immune responses managed by CD29-mediated cell-cell adhesion.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2023.04a
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• pp.15-15
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• 2023

The chloroplast (cp) is an autonomous plant organelle with an individual genome that codes for essential cellular functions. The architecture and gene content of the cp genome is highly conserved in angiosperms. The plastome of Corydalis belongs to the Papaveraceae family, and the genome is comprised of unusual rearrangements and gene content. Thus far, no extensive comparative studies have been carried out to understand the evolution of Corydalis chloroplast genomes. Therefore, the Corydalis platycarpa cp genome was sequenced, and wide-scale comparative studies were conducted using publicly available twenty Corydalis plastomes. Comparative analyses showed that an extensive genome rearrangement and IR expansion occurred, and these events evolved independently in the Corydalis species. In addition, the protein-coding genes accD and the ndh gene loss events occurred in the common ancestor of the Corydalis and sub-clade of the Corydalis lineage, respectively. The gene ndh lost in the Corydalis-sub clade species is distributed predominantly in the Qinghai-Tibetan plateau (QTP) region. The molecular clock analysis suggests that the divergence time of all the ndh gene lost Corydalis sub-clade species occurred in the 44.31 - 15.71 mya. These results coincide very well with the uplift of the Qinghai-Tibet Plateau in the Oligocene and Miocene periods, and maybe during this period, it probably triggered the radiation of the Corydalis species. To the best of the authors' knowledge, this is the first large-scale comparative study of Corydalis plastomes and their evolution. The present study may provide insights into the plastome architecture and the molecular evolution of Corydalis species.

• BMB Reports
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• v.45 no.6
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• pp.365-370
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• 2012

Hepatitis B virus (HBV) DNA is often integrated into hepatocellular carcinoma (HCC). Although the relationship between HBV integration and HCC development has been widely studied, the role of HBV integration in HCC development is still not completely understood. In the present study, we constructed a pooled BAC library of 9 established cell lines derived from HCC patients with HBV infections. By amplifying viral genes and superpooling of BAC clones, we identified 2 clones harboring integrated HBV DNA. Screening of host-virus junctions by repeated sequencing revealed an HBV DNA integration site on chromosome 11q13 in the SNU-886 cell line. The structure and rearrangement of integrated HBV DNA were extensively analyzed. An inverted duplicated structure, with fusion of at least 2 HBV DNA molecules in opposite orientations, was identified in the region. The gene expression of cancer-related genes increased near the viral integration site in HCC cell line SNU-886.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.2
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• pp.491-495
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• 2016

Background: Small B-cell non-Hodgkins lymphoma (NHL) is difficult to be distinguished from non-neoplastic reactive processes using conventional haematoxylin-eosin (HE) staining due to different interpretations among pathologists with diagnosis based on morphologic features. Ancillary examinations such as immunohistochemical (IHC) staining are essential. However, negative or doubtful results are still sometimes obtained due to unsatisfactory tissue processing or IHC technique. The polymerase chain reaction (PCR) as a molecular diagnostic technique is very sensitive and specific. Clonality detection of heavy chain immunoglobulin (IgH) gene rearrangement has been widely used to establish diagnosis of B-cell NHL. Aims: To elaborate interobserver variation in small B-cell NHL diagnosis based on morphologic features only and to confirm sensitivity and specificity of the PCR technique as an ancillary method. Materials and Methods: A toptal of 28 samples of small B cell NHL and suspicious lymphoma were interpreted by 3 pathologists in Sardjito General Hospital based on their morphology only. The reliability of assessment and the coefficient of interobserver agreement were calculated by Fleiss kappa statistics. Interpretation results were confirmed with IHC staining (CD20, CD3, Bcl2). PCR was performed to analyze the clonality of IgH gene rearrangement. Results: Interobserver agreement in morphologic evalution of small B cell NHL and chronic lymphadenitis revealed kappa coefficient 0.69 included in the substantial agreement category. The cases were divided into 3 groups based on morphology and IHC results; lymphoma, reactive process and undetermined group. PCR analysis showed 90% sensitivity and 60% specificity. Conclusions: The present study revealed a substantial agreement among pathologists in small B-cell NHL diagnosis. For difficult cases, PCR is useful as complementary method to morphologic and IHC examinations to establish definitive diagnosis.

• Molecules and Cells
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• v.27 no.3
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• pp.291-297
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• 2009

Apolipoprotein (apo) C-III is a marker protein of triacylglycerol (TG)-rich lipoproteins and high-density lipoproteins (HDL), and has been proposed as a risk factor of coronary heart disease. To compare the physiologic role of reconstituted HDL (rHDL) with or without apoC-III, we synthesized rHDL with molar ratios of apoA-I:apoC-III of 1:0, 1:0.5, 1:1, and 1:2. Increasing the apoC-III content in rHDL produced smaller rHDL particles with a lower number of apoA-I molecules. Furthermore, increasing the molar ratio of apoC-III in rHDL enhanced the surfactant-like properties and the ability to lyse dimyristoyl phosphatidylcholine. Furthermore, rHDL containing apoC-III was found to be more resistant to particle rearrangement in the presence of low-density lipoprotein (LDL) than rHDL that contained apoA-I alone. In addition, the lecithin:cholesterol acyltransferase (LCAT) activation ability was reduced as the apoC-III content of the rHDL increased; however, the CE transfer ability was not decreased by the increase of apoC-III. Finally, rHDL containing apoC-III aggravated the production of MDA in cell culture media, which led to increased cellular uptake of LDL. Thus, the addition of apoC-III to rHDL induced changes in the structural and functional properties of the rHDL, especially in particle size and rearrangement and LCAT activation. These alterations may lead to beneficial functions of HDL, which is involved in anti-atherogenic properties in the circulation.