• Animal Systematics, Evolution and Diversity
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• v.33 no.1
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• pp.8-16
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• 2017

We firstly described a box jellyfish, Carybdea brevipedalia collected from the southern coasts of Korea. It is morphologically characterized by gastric phacellae, a special digestive system of cubozoan jellyfish, and velarium, the thin muscle flap forming the opening of the subumbrellar cavity. The phacellae are linear-shaped, comprising numerous cirri branched from multiple roots. Each root also has multiple numbers of cirrus bundles. Basis of velarial cannels parts into two branches in each octant of velarium. Its geographic distributions were limited to Jeju-do and the middle-southern coasts where the organisms are seriously hazardous to bathers in summer. Numerous individuals and/or large-sized populations were observed specifically from beaches at Jeju-do, Namhae-do and a small fishing port of Namildae, while only a small amount of the individuals was observed in Gamak Bay, Jaran-Goseung Bay, and Geoje-do. We confirmed molecular identity of the Korean C. brevipedalia with comparison of nuclear ribosomal DNA sequences. Until now, Carybdea brevipedalia is the only cubozoan species reported to be distributed in Korean waters.

• Journal of Korean Public Health Nursing
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• v.34 no.2
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• pp.289-300
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• 2020

Purpose: This study aimed to identify gender differences associated with weight related teasing by parents, and development of anti-fat attitudes among Korean children aged 5 to 7 years. Methods: This study used a descriptive cross-sectional design. Questionnaire interviews were conducted by enrolling 222 healthy children having normal development and living with their parents in South Korea. Results: Results showed gender and parental weight-related teasing was significantly associated with anti-fat attitudes among children. Significance of the association between parental weight-related teasing and anti-fat attitudes among kindergarten children differed according to the child's gender. Among girls, the higher level of parental weight-related teasing was associated with greater anti-fat attitude. However, parental weight-related teasing was not associated with increased anti-fat attitude among boys. Conclusion: Considering our study results, we recommend developing programs aimed towards decreasing teasing in the family environment, such as changing the gender-specific weight norms to prevent anti-fat attitudes in Korean girls.

• Journal of the Korean Society of Food Science and Nutrition
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• v.16 no.2
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• pp.128-135
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• 1987

Extracellular ${\alpha}-amylase$, ${\beta}-amylase$ and glucoamylase produced by a thermophilic and cellulolytic bacterium, Herpetosiphon geysericola CUM 317, were partially purified by salting out with ammonium sulfate and by chromatography on a DEAE-cellulose column and on a CM-cellulose column. The Km values of ${\alpha}-amylase$, ${\beta}-amylase$ and glucoamylase for potato starch were $2.31mg/m{\ell}$, $7.69mg/m{\ell}$, and $8.33mg/m{\ell}$. The molecular weights of ${\alpha}-amylase$, ${\beta}-amylase$ and glucoamylase were calculated to be about 84000 dalton, 76000 dalton and 80000 dalton, respectively.

• ALGAE
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• v.23 no.2
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• pp.115-118
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• 2008

Cells of the dinoflagellate Peridinium were frequently observed in water samples of Togyo reservoir, and some species were responsible for dense blooms. Recently, we could identify them as P. bipes f. occultatum Lindem. and P. aciculiferum Lemm., considering morphology (Ki et al. 2005a; Ki and Han 2005b): However, some unidentified Peridinium cells with different shapes and body sizes were found among the samples collected during early spring. Here we describe their morphological characteristics such as thecal plate and body size to characterize its taxonomic identity by morphological characters. The formula of epithecal plates was recorded as 4 apical, 2 intercalary and 7 precingular plates (i.e. 4’', 2a, 7’'’') and the epicone in an apical view was symmetric. An apical pore was easy to make out under a light microscope. No cingular displacement was observed. The average body size was 33 $\mu$m in length with a range of 26-36 $\mu$m, and average 26 $\mu$m in width with a range of 21-31 $\mu$m, respectively; the cell was, therefore, shown slightly elongated. This way we identified Peridinium umbonatum Stein, 1883 for the first time from Korean freshwaters.

• BMB Reports
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• v.42 no.5
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• pp.304-309
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• 2009

Nanoparticulate platinum (II) (nano Pt) is a powerful antioxidant that is widely used to scavenge reactive oxygen species (ROS). The antioxidant activity of nano Pt has gained attention as a potentially useful therapeutic for a variety of diseases including cancer and aging. In the present study, we prepared nanoparticulate saponin-Pt (II) (nano saponin-Pt) conjugates using the ethanol reduction method to enhance the permeability and retention effect of Pt. The nano saponin-Pt conjugates were found to restore the viability of approximately 40% of 2,4-dinitrofluorobenzene (DNFB)-treated RAW 264.7 cells. In addition, we found that nano saponin-Pt conjugates acted as a potent antioxidant that reduced the production of ROS and inhibited activation of the MAP kinase pathway and MIP-2 gene expression in response to DNFB. These results provide insight into the potential usefulness of nano saponin-Pt conjugates as a treatment for contact hypersensitivity.

• BMB Reports
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• v.42 no.5
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• pp.265-270
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• 2009

Due to their multiple biological activities, flavonoids have gained attention as potentially useful therapeutics for a variety of diseases including cancer, cardiovascular diseases, and autoimmune diseases. In this study, we demonstrated that several flavonoids, including kaempferol, quercetin, fisetin, and chrysin block TNF-$\alpha$ induced IL-8 promoter activation and gene expression in HEK 293 cells. In addition, phosphorylation and degradation of $I{\kappa}B{\alpha}$ and translocation of NF-${\kappa}B$ p65 were inhibited by these flavonoids in TNF-$\alpha$-stimulated HEK 293 cells. Furthermore, generation of reactive oxygen species (ROS) in response to TNF-$\alpha$ was reduced by the flavonoids. Moreover, although pretreatment with fisetin, quercetin, or chrysin decreased cell viability, kaempferol did not. Taken together, these findings suggest that kaempferol would be useful for the treatment of TNF-$\alpha$-induced inflammatory diseases.

• ALGAE
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• v.25 no.2
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• pp.65-70
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• 2010

The genus Chaetoceros provides highly diversified diatoms in marine systems. Morphological descriptions of the genus are well-documented, yet the DNA taxonomy of Chaetoceros has not been satisfactorily established. Here, the molecular divergences of the 18S-28S rDNA of Chaetoceros were assessed. DNA similarities were relatively low in both 18S (93.1 $\pm$ 3.9%) and 28S rDNA (81.0 $\pm$ 4.6%). Phylogenies of the 18S, 28S rDNAs showed that Chaetoceros was divided according to individual species, clustering the same species into single clades. Statistical analysis with corrected genetic (p-) distance scores showed that nucleotide divergence of Chaetoceros 28S rDNA significantly differed from that of 18S rDNA (Student's t-test, p < 0.05). This finding suggests that the 28S rDNA may be treated as a more suitable marker for species-level taxonomic distinctions of Chaetoceros.

• Microbiology and Biotechnology Letters
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• v.13 no.4
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• pp.377-382
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• 1985

As an essential previous step towards the development of cell fusion to breed a new brewing yearst strain, several factors predicted to affect the protoplast formation of S. cerevisiae, C. tropicalis and E. fibuligera were investigated in order to obtain the protoplasts in high yields. The optimum pH and temperature for the protoplas formation were 7.5 and 35$^{\circ}C$, respectively. Pretreatment of the yeast cells with 2-mercaptoethanol stimulated the protoplast formation and 50mM of the reagent was found as effective. Among several osmotic stabilizers tested for their effect on protoplas formation, 0.6M KCI was comparatively favorable.

• ALGAE
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• v.24 no.3
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• pp.129-138
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• 2009

DNA-based discrimination of species is a powerful way for morphologically otherwise similar species, like centric diatoms. Here, the author sequenced long-range nuclear ribosomal DNAs, spanning from the 18S to the D5 region of the 28S rDNA, of Stephanodiscus, particularly including a Korean isolate. By comparisons, high DNA similarities were detected from the rDNAs of nine Stephanodiscus (>99.4% in 18S rDNA, >98.0% in 28S rDNA). Their genetic distances, however, were significantly different (Kruskal-Wallis test, p < 0.01) compared to two related genera, namely Cyclotella and Discostella. In addition, genetic distances of 18S rDNAs were significantly different (Student’s t-test, p = 0.000) against those of the 28S rDNAs according to individual genera (Cyclotella, Discostella, and Stephanodiscus). Phylogenetic analyses showed that Stephanodiscus and Discostella showed a sister taxon relationship, and their clade was separated from a cluster of Cyclotella (1.00 PP, 100% BP). This suggests that Stephanodiscus has highly conserved sequences of both 18S and 28S rDNA; however, Stephanodiscus is well-separated from other freshwater centric diatoms, such as Cyclotella and Discostella, at the generic level.

• Journal of Microbiology and Biotechnology
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• v.22 no.1
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• pp.118-125
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• 2012

Heat shock proteins (Hsps) play a key role in the cellular defense response to diverse environmental stresses. Here, the role of Hsp genes in the acquisition of thermotolerance in the cyanobacterium Microcystis aeruginosa NIES-298 was investigated. Twelve Hsp-related genes were examined to observe their modulated expression patterns at different temperatures (10, 15, 25, and $35^{\circ}C$) over different exposure periods. HspA and HtpG transcripts showed an up-regulation of expression at low temperatures (10 and $15^{\circ}C$) and high temperature ($35^{\circ}C$), compared with the control ($25^{\circ}C$). To examine their effects upon thermotolerance, we purified recombinant HspA and HtpG proteins. During a thermotolerance study at $54^{\circ}C$, the HspA-transformed bacteria showed increased thermotolerance compared with the control. HtpG also played a role in the defense response to acute heat stress within 30 min. These findings provide a better understanding of cellular protection mechanisms against heat stress in cyanobacteria.