Jum-Ji Kim

Effects of temperature and salinity on the growth of Gracilaria verrucosa and G. chorda, with the potential for mariculture in Korea

Effects of temperature and salinity on the growth of the two agarophytes, Gracilaria verrucosa (Hudson) Papenfuss and Gracilaria chorda Holmes were examined in Korea. Both species grew over a wide range of temperatures (10–30 ∘C) and salinities (5–35‰), and grew well at 17–30 ∘C and a salinity of 15–30‰. In culture, G. verrucosa grew faster than G. chorda and their maximum growth rates were 4.95% day−1 (30 ∘C, 25‰) and 4.47% day−1 (at 25 ∘C, 25‰), respectively. In the field population the maximum growth and fertility of G. chorda were observed in summer. The growth rate of G. verrucosa was slightly higher than that of G. chorda for 2 weeks on the cultivation rope and in culture but it was much lower after being contaminated with epiphytes. The biomass of the epiphytes was 0.82 g dry wt. per host plant in G. verrucosa and 0.001 g in G. chorda. G. chorda exhibited resistance to epiphytism and grew 7 times in length and the dry weight increased 15 times after 55 days. In conclusion, G. chorda appears to be a good agarophyte with a fast growth rate and resistance to epiphytesm, and compared with G. verrucosa, has good potential for commercial cultivation.

Identification and characterization of adenovirus early region 1B-associated protein 5 as a surface marker on undifferentiated human embryonic stem cells.

Pluripotent human embryonic stem cells (hESCs) provide appropriate systems for developmental studies and prospective donor cell sources for regenerative medicine. Identification of surface markers specific to hESCs is a prerequisite for studying hESC biology and can be used to generate clinical-level donor cell preparations that are free from tumorigenic undifferentiated hESCs. We previously reported the generation of monoclonal antibodies that specifically recognize hESC surface antigens using a decoy immunization strategy. In this study, we show that monoclonal antibody 57-C11 recognizes a phosphorylated form of adenovirus early region 1B-associated protein 5 (E1B-AP5). E1B-AP5 is a nuclear RNA-binding protein, but we report that 57-C11-reactive E1B-AP5 is expressed on the surface of undifferentiated hESCs. In undifferentiated hESCs, 57-C11-reactive E1B-AP5 is localized to SSEA3-, SSEA4-, TRA-1-60-, TRA-1-81-, OCT4-, SOX2-, and NANOG-positive hESCs. In mixtures of undifferentiated hESCs and hESC-derived neurons, 57-C11 exclusively recognizes undifferentiated hESCs but not hESC-derived neuronal cells. Further, the expression of 57-C11-reactive E1B-AP5 decreases upon differentiation. Our results demonstrate that 57-C11-reactive E1B-AP5 is a novel surface molecule that is involved in the undifferentiated state of hESCs. As far as we know, this is the first report demonstrating that heterogeneous nuclear RNA-binding protein is expressed on the surface of undifferentiated hESCs.

Electrolyzed-reduced water confers increased resistance to environmental stresses

Electrolysis of water produces reduced water at the cathode and oxidized water at the anode. Electrolyzed-reduced water (ERW) has an extremely negative oxidation-reduction potential. ERW scavenges cellular reactive oxygen species (ROS) and suppresses single-strand breaks of plasmid DNA in bacteria. Here, we examined the effect of ERW on resistance to oxidative stress both in vitro and in vivo. Oxidative DNA damage in human lymphocytes was significantly alleviated by ERW by reducing cellular ROS levels. Caenorhabditis elegans grown in media prepared with ERW had increased resistance to oxidative stress caused by paraquat. We observed a significant effect of ERW on response to other stressors, including heat shock and UV-irradiation in C. elegans. These data indicate that the powerful anti-oxidant activity of ERW is due to its radical-scavenging activity and show, for the first time, that ERW could increase thermotolerance and resistance to UV-irradiation. These results suggest that ERW aids resistance to various environmental stresses.

Characterization of Monoclonal Antibodies Recognizing 130 kDa Surface Proteins on Human Embryonic Stem Cells and Cancer Cell Lines

To study cell surface proteins expressed on human embryonic stem cells (hESCs), we generated a panel of monoclonal antibodies (MAbs) against undifferentiated hESCs by a decoy immunization strategy in a previous study. Two of the MAbs, 63-B6 and 246-D7, bound to human pluripotent stem cells but not to human primary cells such as human peripheral blood mononuclear cells and human lung fibroblasts. They did not bind to either mouse embryonic stem cells or mouse embryonic fibroblasts. The two MAbs had similar binding profiles for many various cancer cells, with few exceptions. Expression of antigens recognized by the two MAbs was rapidly decreased during embryoid body formation of hESCs and gradually increased after initial decrease. The MAbs recognized approximately 130 kDa proteins on the surface of hESCs. Cloning and sequence analysis of antibody genes showed that although the MAbs had exactly the same light chain sequences, they had different heavy chain sequences. Taken together, the results suggest that the two MAbs may recognize two different epitopes of the same or different 130 kDa surface proteins involved in regulating the early differentiation of human pluripotent stem cells and cancer cells.

Effect of Acanthopanax extract on the DNA and erythrocyte damage induced by herbicides

In order to investigate whether the ethanol extract of Acanthopanax sp. might inhibit herbicide-induced DNA damage and erythrocyte damage, the suppression of the oxidative DNA damage of lymphocyte and erythrocyte damage in the presence of the extract were evaluated by comet assay and hemolysis assay, respectively. Phenoxy herbicides, named 2,4-D (2,4-dichlorophenoxyacetic acid) and 2,4,5-T (2,4,5-trichlorophenoxyacetic acid) and bipyridyl herbicide paraquat induced oxidative DNA damages of lymphocytes. However, the oxidative DNA damage by 2,4-D, 2,4,5-T or paraquat was inhibited in vitro upon treating Acanthopanax extract. Moreover, the erythrocyte damage was also suppressed in vitro by Acanthopanax extract treatment.

Bactericidal Effects of Anodic Electrolyzed Water on the Selected Gram-Negative and Gram-Positive Bacteria

The antibacterial effects of anodic electrolyzed water against various bacteria were studied in this investigation. Complete inactivation of Gram-positive and Gram-negative bacteria occurred within 15 s after exposure to anodic electrolyzed water. Moreover, 1/2, 1/5 and 1/10 diluted anodic electrolyzed water by adding deionized water showed strong antibacterial effects. However, the inhibitory effect of anodic electrolyzed water on the anaerobe of Propionibacterium acnes was much weaker than that on the aerobes, including Gram-positive and Gram-negative bacteria. The degraded fragments of E. coli cell were observed upon treating anodic electrolyzed water for 1 min by using scanning electron microscopy.

Development of hybrid-reduced water and its antioxidative effects

Novel functional reduced water, termed hybrid-reduced water (HRW), was produced without electrolysis using a hybrid-reduction technology. In this study, we examined the antioxidative effect of HRW. HRW suppressed H2O2-induced oxidative damage in lymphocyte DNA in the comet assay system. Moreover, HRW reduced reactive oxygen species (ROS) generation by H2O2. These results suggest that HRW may have ROS scavenging effects.

Effects of Ore Minerals on the Damages of Animal Cells

In this study, we investigated the suppressive effects of ore minerals on the allergic cell damages and oxida- tive cell damages. The ore minerals significantly reduced the productions of tumor necrosis factor-alpha (TNF- ) and interleukin-4 (IL-4) in rat basophilic leukemia cells challenged with 2,4-dinitrophenol-bovine serum α albumin (DNP-BSA). Lipoxygenase activity was also reduced by the ore minerals. Moreover, the ore minerals showed weak protective effects on the oxidative damage induced by hydrogen peroxide in pig kidney cells and retinal ganglion cells. Photohemolysis of erythrocytes in the presence of rose-bengal as a sensitizer was also inhibited by ore minerals. These results suggest that the ore minerals may be useful as the protectant for allergic and oxidative cell damages.