• The Journal of the Korean Society for Microbiology
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• v.21 no.2
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• pp.171-179
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• 1986

The HLA class II region encodes a series of polymorphic glycoproteins that form cell surface heterodimers each consisting of one $\alpha$ and one $\beta$ chain. Thess class II molecules are encoded by genes clustered within three loci. DP, DQ, and DR are functfonally implicated as regulatory signals in intercellular communication during the immune resposes. The phenotypic hallmark of the HLA complex is a high degree of structural and functional polymorphism. Detailed analysis. of such polymorphisms should aid in understanding the molecular basis for associations between HLA and diseases. We have used techniques of restriction enzyme fragment analysis by Southern blotting to investigate polymorphisms associated with DQ $\beta$ class II genes on haplotypes expressing the HLA-DR4 and -DQw3 specificities. The endonucleases Hind III and Bam HI were used to identify a specific DQ $\beta$ genomic polymorphism that precisely corrresponds with the reactivity of a monoclonal antibody A-10-83, previously shown to define a serologic split of DQw3. This study identifies two allelic DQ va. riants. DQw3.1 and DQw3.2. We used these specific genotypic markers to investigate the genomic basis of the association of DR4 with insulin-dependent diabetes mellitus(IDDM) and seropositive juvenile rheumatoid arthritis(JRA). The DR4 positive IDDM demonstrate the predominant expression of DQw3.2 and the very rare expression of DQw3.l. However, in haplotype matched siblings from two IDDM families, all of the DR4 positive siblings display a IDDM-associated DQw3.2 allele. Thus, both affected and healthy individuals can carry the same haplotypes and genomic markers, demonstrating that thess specific allelic variants are genetic elements that indicate a increased risk of IDDM but are not in fact disease specific. We contrasted this result with a similar analysis of patients with another DR4-associated disease, JRA. In contrast to the preponderance of the DQw3.2 allele in IDDM, the JRA patients expressed either the DQw3.1 or the DQw3.2 allele and sometimes both, without apparent association with disease expession. The different genomic markers reported here within HLA-DQ region potentially an analysis of HLA-associated function and disease susceptibility.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.11
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• pp.3066-3073
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• 2009

Joint paths of master and branch pipes are induced mathematically for many kinds of joint patterns between both pipes in 3-axis pipe profile-cutting machines. By compensating them with a kerf width, the real cutting paths are determined, and their CL-data are generated, and the tool paths generated by CL-data are verified by a ghost function. A bevelling of welds is implemented through tilting a cutting torch in the $\beta$-axis direction for 8 sections in the chuck rotation of $\alpha$-axis. A PLC controls simultaneously position and velocity in a real time for $\alpha$, X, $\beta$-axis by loading CL-data generated. We developed the PLC-controlled 3-axis pipe profile-cutting system which can cut a master or branch pipe along the cutting path and simultaneously do a bevelling process.

• Journal of Life Science
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• v.24 no.1
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• pp.98-103
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• 2014

NAD(P)H quinone oxidoreductase 1 (NQO1) is a flavoprotein that catalyzes the two electron reduction of diverse substrates, including quinones. It uses NADH or NADPH as a cofactor for enzymatic machinery. In the metabolism of quinones, NQO1 has two conflicting functions because of the different stability of converted hydroquinones. The stable form of hydroquinone is excreted from cells by conjugation with glutathione or glucuronic acid. The unstable form of hydroquinone induces cell death by induction of oxidative stress and DNA damage. Certain quinones known as bio-reductive agents have a cytotoxic function following reduction by NQO1. Bio-reductive agents, such as ${\beta}$-lapachone or mitomycin C, induce the depletion of NAD(P)H and the generation of oxidative stress in an NQO1-dependent manner. NQO1 is highly expressed in several cancer tissues. Therefore, NQO1 is a good therapeutic target for cancer treatment with bio-reductive agents.

• Archives of Pharmacal Research
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• v.23 no.2
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• pp.182-186
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• 2000

Chondroitin sulfates proteoglycans were isolated from human placenta. For the identification of enzymatic digestion products of isolated proteoglycan, strong anion exchange-high performance liquid chromatography (SAX-HPLC) was performed. By the action of chondroitin ABC and chondroitin B lyase, three unsaturated disaccharides 2-acetamide-2-deoxy-3-O-($\beta$-D-gluco-4-enepyranosyluronic acid)-D-galactose ($\delta$Di-OS), 2-acetamide-2-deoxy-3-O-($\beta$-D-gluco-4-enepyranosyluronic acid)-6-O-su lfo-D-galactose ($\delta$Di-6S) and 2-acetamide-2-deoxy-3-O-($\beta$-D-gl uco-4-enepyranosyluronic acid)-4-O-sulfo-D-galactose ($\delta$Di-4S) were produced from the human placenta proteoglycan. The anticoagulant activity of chondroitin sulfate proteoglycan was evaluated by activated partial thromboplastin time (aPTT) assay and thrombin time (TT) assay. The clotting times of aPTT and TT were increased from 72 to 144 sec and 19 to 27 sec, respectively. The Immune-modulating activity of chondroitin sulfate proteoglycan was examined by cell proliferation assay and these results suggest that it may play a role in suppression of the function of immune-related cells.

• Proceedings of the Korean Biophysical Society Conference
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• 2003.06a
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• pp.47-47
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• 2003

The presenilin 1 (PS1) or PS2 is an essential component of the ${\gamma}$-secretase complex, which mediates the intramembrane proteolysis of selected type-I membrane, including the ${\beta}$-amyloid precursor protein (APP) to yield A${\beta}$. Familial Alzheimer's disease (FAD)-associated mutations in presenilins give rise to an increased production of a highly amyloidogenic A${\beta}$42. In addition to their well-documented proteolytic function, the presenilins play a role in calcium signaling. We have previously reported that presenilin FAD mutations cause highly consistent alterations in intracellular calcium signaling pathways, which include deficits in capacitative calcium entry (CCE), the refilling mechanism for depleted internal calcium stores. However, molecular basis for the presenilin-mediated modulation of CCE remains to be elucidated. In the present study, whole-cell patch clamp method was used to identify a specific calcium-permeable ion channel current(s) that is responsible for the CCE deficits associated with FAD-linked PS1 mutants. Unexpectedly, both voltage-activated and conventional store depletion-activated calcium currents I(CRAC), were absent in HEK293 cells, which were stably transfected either with wild-type or FAD mutant (L286V, M146L, and delta E9) forms of PS1. Recently, magnesium-nucleotide-regulated metal cation current, or I(MagNum), has been described and appears to share many common properties with I(CRAC) including calcium permeability and inhibitor sensitivity (e.g. 2-APB). We have detected I(MagNum) in all 293 cells tested. Interestingly, FAD mutant 293 cells developed only about half of currents compared to PS1 wild type cells.

• Journal of Technologic Dentistry
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• v.21 no.1
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• pp.5-14
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• 1999

Glass ceramics for dental crown prosthesis were prepared by crystallization of CaO-MgO-SiO2-$P_2O_5-TiO_2$ glasses. Their crystallization behaviors have been investigated as a function of heattreatment temperature, holding time and chemical composition in relation to mechinical properties. Crystallization peak temperatures were determined by differential thermal analysis(DTA). Crystalline phases and mircostructures of heat-treated sample were determined by the means of powder X-ray diffraction(XRD) and scanning electron microscopy(SEM). The final crystalline phase assemblages and the microstructures of the samples were found to be dependent on glass compositions, heattreatment temperature, and holding time. 1st crystallization peak temperature(TP), affected strongly by apatite, was found to be increased or decreased. From the experiment, the following results were obtained : 1. The crystallization peak temperature($T_P$) formed by apatite increased until adding up to 9wt% $TiO_2$ to base glass composition, then decreased above that. 2. Apatite($Ca_{10}P_6O_{25}$), whitlockite(${\beta}-3CaO-P_2O_5$), $\beta$-wollastonite($CaSiO_3$), magnesium tianate($MaTiO_3$) and diopside(CaO-MgO-$2SiO_2$) crystal phase were precipitated in MgO-CaO-$SiO_2-TiO_2-P_2O_5$ glass system containing 9wt% and 11wt% of $TiO_2$ 3. Vickers hardness of samples increased with increasing heat-treatment temperature and Vickers hardness of S415T9 samples heat-treated at 1075 was approxi-mately 813Kg $mm^{-2}$ as maximum value. 4. Vickers hardness of samples increased due to precipitation of apatite, whitlockite, $\beta$-wollastonite, magnesium titanate, and diopside crystal phases within glass matrix.

• Journal of Korean Academy of Nursing
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• v.46 no.6
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• pp.836-847
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• 2016

Purpose: The purpose of this study was to examine the association between utilization of home care services under the national long-term care insurance system and family caregiver distress. Methods: A secondary data analysis was conducted in this study using data collected in 2011 and 2012 from the Korean version of International Resident Assessment Instrument (interRAI) Home Care assessment system. The study sample included 228 clients receiving community based home care and their family caregivers in Korea. Descriptive statistics, $x^2$ test, t-test, and Heckman selection model analysis were conducted using SAS 9.3. Results: Presence of family caregiver distress was significantly associated with days of nurse visits (${\beta}$=-.89, p=<.001) and home helper visits (${\beta}$=-.53, p=.014). Level of caregiver distress was also significantly associated with days of nurse visits (${\beta}$=-.66, p=.028). Other factors which were significantly associated with caregiver distress were depression, cognitive function, inadequate pain control, social support for older adult, and caregiver relationship to the older adult. Conclusion: The results of this study show that visiting nurse service and appropriate support programs for Older Adults and family caregivers experiencing caregiver distress should be developed and provided to families based on the health care needs of older adults and their family caregivers for effective and sustainable home care.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1545-1547
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• 2000

The mechanical and electrical properties of the hot-pressed and annealed $\beta$-Sic-$TiB_2$ electroconductive ceramic composites were investigated as function of the liquid forming additives of $Al_{2}O_{3}+Y_{2}O_3$. Phase analysis of composites by XRD revealed $\alpha$-SiC(6H), $TiB_2$, and YAG($Al_{5}Y_{3}O_{12}$). The relative density and the mechanical properties of composites were increased with increasing $Al_{2}O_{3}+Y_{2}O_3$ contents because YAG of reaction between $Al_{2}O_3$ and $Y_{2}O_3$ was increased. The Flexural strength showed the highest value of 432.5MPa for composites added with l2wt% $Al_{2}O_{3}+Y_{2}O_3$ additives at room temperature. Owing to crack deflection, crack bridging, phase transition and YAG of fracture toughness mechanism. the fracture toughness showed 7.1MPa${\cdot}m^{1/2}$. For composites added with l2wt% $Al_{2}O_{3}+Y_{2}O_3$ additives at room temperature The electrical resistivity and the resistance temperature coefficient respectively showed the lowest of 6.0${\sim}10^{-4}{\Omega}{\cdot}$ cm and 3.1${\times}10^{-3}/^{\circ}C$ for composite added with l2wt% $Al_{2}O_{3}+Y_{2}O_3$ additives at room temperature. The electrical resistivity of the composites was all positive temperature coefficient resistance(PTCR) in the temperature range of 25$^{\circ}C$ to 700$^{\circ}C$.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1474-1476
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• 2000

The mechanical and electrical properties of the hot-pressed and annealed $\beta$-Sic-$ZrB_2$ electroconductive ceramic composites were investigated as function of the liquid forming additives of $Al_{2}O_{3}+Y_{2}O_{3}$. Phase analysis of composites by XRD revealed $\alpha$-SiC(6H), $ZrB_2$, and YAG($Al_{5}Y_{3}O_{12}$). The relative density of composites were increased with increasing $Al_{2}O_{3}+Y_{2}O_{3}$ contents. The flexural strength showed the highest value of 390.6MPa for composites added with 20wt% $Al_{2}O_{3}+Y_{2}O_{3}$ additives at room temperature. Owing to crack deflection, crack bridging. phase transition and YAG of fracture toughness mechanism. the fracture toughness showed the highest value of 6.3MPa${\cdot}m^{1/2}$ for composites added with 24wt% $Al_{2}O_{3}+Y_{2}O_{3}$ additives at room temperature. The electrical resistivity of the composites was all positive temperature coefficient resistance (PTCR) in the temperature range of 25$^{\circ}C$ to 900$^{\circ}C$.

• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.1634-1636
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• 2000

The mechanical and electrical properties of the hot-pressed and annealed $\beta$-SiC-$TiB_2$ electroconductive ceramic composites were investigated as function of the liquid forming additives of $Al_{2}O_{3}+Y_{2}O_3$ and the annealing method. Phase analysis of composites by XRD revealed $\alpha$-SiC(6H), $TiB_2$, and YAG($Al_{5}Y_{3}O_{12}$). In pressureless annealing method, the relative density and the mechanical properties of composites were increased with increasing $Al_{2}O_{3}+Y_{2}O_3$ contents because YAG of reaction between $Al_{2}O_3$ and $Y_{2}O_3$ was increased. But In pressured annealing method, reaction between $Al_{2}O_3$ and $Y_{2}O_3$ formed YAG but the relative density decreased with increasing $Al_{2}O_{3}+Y_{2}O_3$ contents. The electrical resistivity of the composites was all positive temperature coefficient resistance (PTCR) in the temperature range of 25$^{\circ}C$ to 700$^{\circ}C$.