• Applied Chemistry for Engineering
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• v.2 no.4
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• pp.348-355
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• 1991

Polysiloxane copolymers were prepared by copolymerizing hexamethylcyclotrisiloxane with tetramethylcyclotetrasiloxane, and then reacted with allyamine. Copolymers containing naphthoquinone-1,2-diazide-5-sulfonyl group were synthesized by reacting naphthoquinone-1,2-diazide-5-sulfonyl chloride with siloxane copolymers having amino group. Thermal decomposition temperatures of copolymers were $360{\sim}450^{\circ}C$, and photosensitive characteristics were dependent on the molecular weights of backbone resins and sensitizers. Sensitivity of copolymers was $50{\sim}120mJ/cm^2$ and contrast(${\gamma}$) was 1.4~2.1.

• Food Science and Biotechnology
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• v.16 no.3
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• pp.355-360
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• 2007

During the traditional production process of yugwa, a Korean traditional oil-puffed snack, three bacterial isolates, 12, 37, and B1 from waxy rice slurry were characterized by using the molecular techniques, and the quality of the yugwa prepared by using three isolates was examined in relation to physical and sensory properties. Isolates 37 and B1 were identified as Lactobacillus sp. by 16S rDNA sequence analysis, while isolate 12 was as Bacillus amyloliquefaciens by gyrA sequence analysis. Waxy rice inoculated with isolate 12 demonstrated the lowest hardness and the highest peak and [mal viscosity. Yugwa prepared from isolate 12-inoculated waxy rice indicated the lowest hardness and the highest volume expansion, the key characteristics of yugwa. This result presents the possibility for the use of a starter in the commercial production of yugwa and other rice-based snacks.

• Journal of Pharmacopuncture
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• v.14 no.2
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• pp.5-14
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• 2011

Objectives: Fibrinolytic enzyme preparations were isolated from the snake venom of Macrovipera lebetica turanica in this study. Methods: The purity of the preparations was determined using SDS-PAGE and the enzymic characteristics of the purified fibrinolytic enzyme were determined. Results: 1. All of the two preparations with fibrinolytic activity obtained from the snake venom of M. l. turanicat contained the major polypeptide with the molecular weight of 27,500. One of the preparation showed purified fibrinolytic enzyme. 2. The purified fibrinolytic enzyme hydrolyzed ${\alpha}$-chain of fibrinogen faster than ${\beta}$-chain but not ${\gamma}$-chain. 3. The fibrinolytic activity was inhibited completely by EDTA, EGTA, 1,10-phenanthroline, and dithiothreitol. 4. The fibrinolytic activity was inhibited completely by calcium chloride, iron(III) chloride, mercuric chloride, and cobalt (II) chloride. 5. The fibrinolysis zone formed after addition of zinc sulfate was smaller but clearer than the control. Conclusions: These results suggested that the fibrinolytic enzyme purifed from the snake venom of M. l turanica was a metalloprotease containing dithiol group.

• Biomedical Science Letters
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• v.10 no.2
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• pp.137-142
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• 2004

The peroxisome proliferator-activated receptor $\gamma$ (PPAR${\gamma}$) is the molecular target for a class of drugs, the antidiabetic thiazolidnediones (TZDs). The heterodimer of PPAR${\gamma}$ with retinoid X receptor (RXR) plays a central role in the regulation of adipogenesis and insulin sensitization. We synthesized two chemicals, DANA87 and DANA88, sharing structural characteristics with TZDs. Given this structural similarity, it was hypothesized that DANA87 and DANA88 may act as PPAR$\gamma$ ligands. In transient transfection assays, DANA87 and DANA88 caused slight increases in the endogenous expression of a luciferase reporter gene containing the PPAR responsive element in 3T3-L1 preadipocytes. However, DANA87 and DANA88 significantly inhibited troglitazone-induced reporter gene activation when cells were treated with a combination of DANA87 or DANA 88 and troglitazone, one of the TZDs that activate PPAR$\gamma$. These results suggest that DANA87 and DANA88 are not only weak agonists of PPAR${\gamma}$ transactivation, but also competitively antagonize troglitazone-induced PPAR$\gamma$ reporter activity.

• Proceedings of the Korean Society of Embryo Transfer Conference
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• 2001.05a
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• pp.12-21
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• 2001

To identify genes implicated in the control of pluripotency as well as characteristics of stem cells, we analyzed expression profiles of genes derived from mouse morulas, blastocysts, embryonic stem cells, mesenchymal stem cells, and uterus tissue using cDNA microarray. Comparative analyses of their expression profiles identified putative clones that expressed specifically in specific samples or not in a specific sample. The expression pattern of these condidate clones was analyzed using RT-PCR and non-radioactive in situ hybridization. Functional annotation of these clones on pluripotency and stem cell plasticity is in ongoing. These studies may further our understanding on the nature of the stem cells and molecular mechanisms underlying many facets of mammalian development and differentiation.

• Parasites, Hosts and Diseases
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• v.55 no.1
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• pp.77-79
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• 2017

The infection by Limnodrilus hoffmeisteri $Clapar{\grave{e}}de$, 1862 (Oligochaeta: Tubificinae) in humans is relatively uncommon. The present report is to describe an incidental human infection with oligochaetes in the nasal cavity of a Chinese man, a 25-year-old man residing in Zhangjiakou city, Hebei province, China presenting with nose bleed, severe itching, continuous sneezing, and rhinorrhea. A lot of oligochaete worms were found in the nasal discharge of the patient. The detected worms were identified as Limnodrilus hoffmeisteri (Annelida: Oligochaeta) based on morphological and molecular characteristics. This incidental L. hoffmeisteri nasal infection is the first case in China and indicates that oligochaete worms can be encountered in humans.

• Transactions of Materials Processing
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• v.12 no.1
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• pp.3-10
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• 2003

The formation of surface defects associated with Jotting in injection molding is related to the geometries of cavity and fate, operational conditions and the rheological properties of polymer. In this study we have examined jetting phenomena in injection molding process for the throe kinds of PCs which have different molecular weights and structures, PBT and PC/ABS alloy with several injection speeds. We have used various cavity shapes those are tensile, flexural and impact test specimens with various gates and cavity thicknesses. Through this study we have observed that the jetting is related to the dic swell of material. This means that the jotting is strongly affected by the elastic flow property rather than the viscous flow property in viscoelastic characteristics of molten polymer. Different resins have different elastic properties, and elastic flow behavior depends on the shear rate of flow, i.e. injection speed. Large die swell would eliminate jetting however, the retardation of die swell would stimulate jetting. In the point of mole design, reducing the thickness ratio of cavity to gate can reduce or eliminate jetting regardless of amount of elasticity of polymer melt.

• Korean Journal of Veterinary Research
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• v.36 no.2
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• pp.371-378
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• 1996

Three and 2 strains of E coli O157 were isolated from fecal materials of cattle (390) and pigs (420) in Korea, respectively. One strain of O157:H7 isolated from cattle and 2 strains of O157:H7 isolated from pigs were identified as verotoxin-1 (VT-1) produing strains and 2 strains (O157:H7 and O157:H-) isolated from cattle were identified as verotoxin-2 (VT-2) producing strains by neutralization test on HeLa and Vero cells. Culture supernatants of the isolates were cytotoxic to HeLa and Vero cells. The levels of cytotoxin produced by isolates were $10^2{\sim}10^4$ cytotoxic dose($CD_{50}$)/ml. Also, VT-2-converting bacteriophage was isolated from KSC109 strain which had been isolated from cattle. Molecular weight of the phage DNA was determined as approximately 45 Kb in 0.8% agarose gel electrophoresis, and morphology of the phage stained with phosphotungstic acid was observed by transmissible electron microscopy.

• Journal of Microbiology
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• v.44 no.1
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• pp.113-120
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• 2006

Candida tropicalis was treated with ultraviolet (UV) rays, and the mutants obtained were screened for xylitol production. One of the mutants, the UV1 produced 0.81g of xylitol per gram of xylose. This was further mutated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), and the mutants obtained were screened for xylitol production. One of the mutants (CT-OMV5) produced 0.85g/g of xylitol from xylose. Xylitol production improved to 0.87 g/g of xylose with this strain when the production medium was supplemented with urea. The CT-OMV5 mutant strain differs by 12 tests when compared to the wild-type Candida tropicalis strain. The XR activity was higher in mutant CT-OMV5. The distinct difference between the mutant and wild-type strain is the presence of numerous chlamvdospores in the mutant. In this investigation, we have demonstrated that mutagenesis was successful in generating a superior xylitol-producing strain, CT-OMV5, and uncovered distinctive biochemical and physiological characteristics of the wild-type and mutant strain, CT-OMV5.

• Korean Journal of Microbiology
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• v.24 no.3
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• pp.302-307
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• 1986

In order to investigate the properties of cephalospornase, a strong antibiotic resistant strain(H 112) was isolated from Pseudomonas aeruginose. The extracted enzyme had the following characteristics. Optimum temperature was 45.deg.C and unstable over $55^{\circ}C$, and optimum pH was 8.5. Cephalosporinase activity was not inhibited by metal ions such as $Mn^{++},\;Cu^{++}\;Fe^{++},\;Fe^{+++}$, and EDTA. But it was inhibited by some antibiotics such as carbenicillin, cefoxitin, cefotaxime, cefamandole, cefoperazone and SDS. The Vmax values of the enzyme were 100 at cephaloridine and 2.8 at cefoperazone, respectively. The molecular weight of cephalosporinase was estimated to be about $37.500{\pm}3,000$ by high performance liquid chromatography and nitrocefin reaction.