• Molecules and Cells
• /
• v.21 no.3
• /
• pp.343-355
• /
• 2006

Stem cells are unique cell populations with the ability to undergo both self-renewal and differentiation, although a wide variety of adult stem cells as well as embryonic stem cells have been identified and stem cell plasticity has recently been reported. To identify genes implicated in the control of the stem cell state as well as the characteristics of each stem cell line, we analyzed the expression profiles of genes in human embryonic, hematopoietic ($CD34^+$ and $CD133^+$), and mesenchymal stem cells using cDNA microarrays, and identified genes that were differentially expressed in specific stem cell populations. In particular we were able to identify potential hESC signature-like genes that encode transcription factors (TFAP2C and MYCN), an RNA binding protein (IMP-3), and a functionally uncharacterized protein (MAGEA4). The overlapping sets of 22 up-regulated and 141 down-regulated genes identified in this study of three human stem cell types may also provide insight into the developmental mechanisms common to all human stem cells. Furthermore, our comprehensive analyses of gene expression profiles in various adult stem cells may help to identify the genetic pathways involved in self-renewal as well as in multi-lineage specific differentiation.

• Molecules and Cells
• /
• v.21 no.3
• /
• pp.428-435
• /
• 2006

Specific interaction of the epsin N-terminal homology(ENTH) domain with the plasma membrane appears to bridge other related proteins to the specific regions of the membrane that are invaginated to form endocytic vesicles. An additional $\alpha$-helix, referred to as helix 0 (H0), is formed in the presence of the soluble ligand inositol-1,4,5-trisphosphate [$Ins(1,4,5)P_3$] at the N terminus of the ENTH domain (amino acid residues 3-15). The ENTH domain alone and full-length epsin cause tubulation of liposomes made of brain lipids. Thus, it is believed that H0 is membrane-inserted when it is coordinated with the phospholipid phosphatidylinositol-4,5-bisphosphate [$PtdIns(4,5)P_2$], resulting in membrane deformation as well as recruitment of accessory factors to the membrane. However, formation of H0 in a real biological membrane has not been demonstrated. In the present study, the membrane structure of H0 was determined by measurement of electron paramagnetic resonance (EPR) nitroxide accessibility. H0 was located at the phosphate head-group region of the membrane. Moreover, EPR line-shape analysis indicated that no pre-formed H0-like structure were present on normal acidic membranes. $PtdIns(4,5)P_2$ was necessary and sufficient for interaction of the H0 region with the membrane. H0 was stable only in the membrane. In conclusion, the H0 region of the ENTH domain has an intrinsic ability to form H0 in a $PtdIns(4,5)P_2$-containing membrane, perhaps functioning as a sensor of membrane patches enriched with $PtdIns(4,5)P_2$ that will initiate curvature to form endocytic vesicles.

• The Korean Journal of Food And Nutrition
• /
• v.20 no.2
• /
• pp.195-201
• /
• 2007

This study were investigated the changes in chemical components, quality characteristics of the fermented broth, and physiological functionality during fermentation period of fruit, vegetables, and medicinal herbs. pH and $^{\circ}$Bx gradually decreased and the viscosity increased. The chromaticity of L, a, and b all increased. The total number of germs dropped from $10^5{\sim}10^6\;to\;10^2{\sim}10^3$ CFU/ml, and that of lactobacilli also decreased noticeably. According to the result of the effect on fat oxidation, a very low level of TBARS was shown. After thirty days of fermentation, the amount of each fermentation broth increased more or less, but as it declined considerably after ninety days, it was found that the binding effect of $Fe^{2+}$ ion was small and insignificant. The electron donating ability, though not reaching 0.5% ascorbic acid, showed a high level of activity from $33.71{\sim}72.15%$ before fifteen days and $44.76{\sim}75.20%$ ninety days after fermentation. Among them, the fruit fermentation solution showed the highest activity. It was also found that the organic functions for each fermentation broth decreased more or less depending on the fermentation period and the thirty-days-old fermentation broth were favored most. On the basis of the above experiment results, it can be concluded that the optimum fermentation period for fruit, vegetables, and medicinal herb is thirty to ninety days.

• Membrane Journal
• /
• v.27 no.2
• /
• pp.129-137
• /
• 2017

In this study, we have developed cation-exchange membranes (CEMs) which can efficiently separate heavy-metal ions among the cations contained in a water system. Sulfonated polyetheretherketone (SPEEK) was used as a base polymer and a powdered chelating resin with strong binding ability to heavy-metal ions was added into it. In order to optimize the performance of the CEM, the content of chelating resin powder and the ion exchange capacity of SPEEK have been controlled. As a result, it was confirmed that the removal efficiency of heavy metal ion was improved by more than 20% by applying the CEM to membrane capacitive deionization (MCDI).

• The Korean Journal of Pain
• /
• v.28 no.1
• /
• pp.4-10
• /
• 2015

Etifoxine (etafenoxine, $Stresam^{(R)}$) is a non-benzodiazepine anxiolytic with an anticonvulsant effect. It was developed in the 1960s for anxiety disorders and is currently being studied for its ability to promote peripheral nerve healing and to treat chemotherapy-induced pain. In addition to being mediated by $GABA_A{\alpha}2$ receptors like benzodiazepines, etifoxine appears to produce anxiolytic effects directly by binding to ${\beta}2$ or ${\beta}3$ subunits of the $GABA_A$ receptor complex. It also modulates $GABA_A$ receptors indirectly via stimulation of neurosteroid production after etifoxine binds to the 18 kDa translocator protein (TSPO) of the outer mitochondrial membrane in the central and peripheral nervous systems, previously known as the peripheral benzodiazepine receptor (PBR). Therefore, the effects of etifoxine are not completely reversed by the benzodiazepine antagonist flumazenil. Etifoxine is used for various emotional and bodily reactions followed by anxiety. It is contraindicated in situations such as shock, severely impaired liver or kidney function, and severe respiratory failure. The average dosage is 150 mg per day for no more than 12 weeks. The most common adverse effect is drowsiness at the initial stage. It does not usually cause any withdrawal syndromes. In conclusion, etifoxine shows less adverse effects of anterograde amnesia, sedation, impaired psychomotor performance, and withdrawal syndromes than those of benzodiazepines. It potentiates $GABA_A$ receptor-function by a direct allosteric effect and by an indirect mechanism involving the activation of TSPO. It seems promising that non-benzodiazepine anxiolytics including etifoxine will replenish shortcomings of benzodiazepines and selective serotonin reuptake inhibitors according to animated studies related to TSPO.

• Applied Biological Chemistry
• /
• v.40 no.6
• /
• pp.546-550
• /
• 1997

This study was carried out to elucidate the biological characteristics of Rhizobia in biological nitrogen fixation system. The results of investigation were as follows; Polyacrylamide gel electrophoresis pattern of root lectin in the presence of SDS was ascertained electrophoretically and chromatographically. The purified root lectin formed immunoprecipitin line with anti lectin rabbit IgG. Root lectin, seed lectin and root exudate were tested for chemotactic ability. Chemotactic responses of RCR3407 and KCTC2422 toward root exudate were stronger than those of seed lectin and root lectin, but there didn't occur chemotactic responses of LPN100, not bound with seed lectin and that of LPN101, bound with seed lectin toward root exudate, root lectin and seed lectin. RCR3407, KCTC2422 and LPN-101, which nodulated with soybean, interacted with soybean lectin, but not with pea lectin. LPN-100, which was not nodulated with soybean, didn't interact with soybean lectin.

• Food Science and Biotechnology
• /
• v.16 no.6
• /
• pp.1011-1017
• /
• 2007

Saeujeot (salted and fermented shrimp) and kimchi are traditional Korean fermented foods. Even though shrimp have often induced severe allergic reactions in sensitized individuals, few studies have investigated the allergenicity of shrimp. The aim of this study was to observe the changes of pH and allergenicity of raw shrimp (Acetes japonicus) and saeujeot in cabbage kimchi during fermentation using competitive indirect enzyme-linked immunosorbent assay (Ci-ELISA). Fermentation was carried out at different temperatures (25, 15, and $5^{\circ}C$). The pH of cabbage kimchi added with raw shrimp or saeujeot slowly decreased at lower temperature ($5^{\circ}C$) at the end stage of the fermentation process. The binding ability of serum obtained from patients allergic to raw shrimp against shrimp tropomyosin and saeujeot in kimchi rapidly decreased during longer fermentation periods and higher temperature ($25^{\circ}C$). In conclusion, the allergenicity of both raw shrimp and saeujeot in kimchi decreased during fermentation but the decrease in allergenicity of saeujeot was greater than observed for raw shrimp.

• Journal of Radiation Protection and Research
• /
• v.20 no.2
• /
• pp.71-78
• /
• 1995

To develop methods to reduce radiation risk and apply such knowledge to improvement of radiation protection, the effects of cobaltous chloride known as bioantimutagen on the function of E. coli RecA protein involved in the repair of DNA damage were examined. The results demonstrated two distinct effects of cobaltous chloride on the RecA protein function necessary for the strand exchange reaction. Cobaltous chloride enhanced the ability of RecA protein to displace SSB protein from single-stranded DNA and the duplex DNA-dependent ATPase activity. RecA protein was preferentially bound with UV-irradiated supercoiled DNA as compared with nonirradiated DNA The binding of RecA protein to UV-irradiated supercoiled DNA was enhanced in a dose-dependent manner. It is likely that studies on the factors affecting repair efficiency and the DNA repair proteins may provide information on the repair of ionizing radiation-induced DNA damage and the mechanism for DNA radioprotection.

• Korean Journal of Poultry Science
• /
• v.40 no.3
• /
• pp.243-252
• /
• 2013

Among the 16 hemagglutinin (HA) subtypes of avian influenza virus (AIV), only the H5 and H7 subtypes have caused highly pathogenic avian influenza (HPAI) in poultry. However, most H5 or H7 subtype viruses are categorized as low pathogenic avian influenza (LPAI). Some AIVs, including the H5 and H7 HPAI viruses, have shown the ability to infect humans directly. In this study, we describe the biological and molecular characterization of an H5N3 AIV (SBD/KR/KNU SYG06/06) isolated from spot-billed duck (Anas poecilorhyncha) in Korea. A phylogenetic analysis of the eight viral genes showed that the SBD/KR/KNU SYG06/06 isolate belongs to the Eurasian lineage and that the SBD/KR/KNU SYG06/06 isolate was clearly different from HPAI H5N1 strains, including human isolates and the Italian HPAI H5N2 strains. Additionally, no relationship was found between SBD/KR/KNU SYG06/06 and the Korean HPAI H5N1 isolates. The SBD/KR/ KNU SYG06/06 isolate had avian specific receptor binding site residues in the HA protein and the four C-terminal amino acids in the NS1 protein. The HA protein of the SBD/KR/KNU SYG06/06 isolate exhibited the typical LPAI motif at the cleavage site and this virus produced no cytopathic effects in MDCK cells without trypsin. Given these results, we suggest that the H5N3 AIV isolated from the spot-billed duck should be considered an LPAI virus and should have no pathogenic effect in humans.

• Food Science of Animal Resources
• /
• v.33 no.2
• /
• pp.221-228
• /
• 2013

This study was performed to evaluate the effects of various levels of mungbean flour (MF) (0-2.4%) on the quality characteristics of pork model sausages (PMS) in experiment 1 and also select the optimum level of MF to enhance the water retention and gelling properties of low-salt PMS (LSPMS) with or without microbial transglutaminase (MTGase) in experiment 2. In experiment 1, the addition of MF did not affect pH, chemical compositions (fat and moisture contents), color values, and functional properties (expressible moisture, EM (%) and cooking yield, CY (%)) of PMS. However, the addition of MF increased the chewiness of PMS and hardness if the mungbean flour at the level of more than 1.2% was incorporated. Since the interaction between the microbial transglutaminase (MTGase) treatment and MF level was not significant (p>0.05), data were pooled by different factors (MTGase treatment and MF level) in experiment 2. MF improved the water binding ability and textural springiness of LSPMS. On the other hand, MTGase treatment decreased the pH and cooking yield (%) of LSPMS, but increased most textural properties. In conclusion, the addition of MF could enhance the water retention and textural properties of PMS and LSPMS, regardless of MTGase, when it was added to over 1.2%. Based on these results, mungbean protein may interact with MTGase on the low-salt comminuted meat systems. Therefore, further study might be needed to understand the mechanisms of interaction between MTGase and functional components induced from MF.