• Molecular & Cellular Toxicology
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• v.5 no.3
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• pp.230-236
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• 2009

Acrolein, a known toxin in cigarette smoke, is the most abundant electrophilic $\alpha$, $\beta$-unsaturated aldehyde to which humans are exposed in a variety of environmental pollutants, and is also product of lipid peroxidation. Increased unsaturated aldehyde levels and reduced antioxidant status plays a major role in the pathogenesis of various diseases such as diabetes, Alzheimer's and atherosclerosis. The findings reported here show that low concentrations of acrolein induce heme oxygenase-1 (HO-1) expression in RAW 264.7 macrophages. HO-1 induction by acrolein and signal pathways was measured using reverse transcription-polymerase chain reaction, Western blot and immunofluorescence staining analyses. Inhibition of extracellular signal-regulated kinase activity significantly attenuated the induction of HO-1 protein by acrolein, while suppression of Jun N-terminal kinase and p38 activity did not affect induction of HO-1 expression. Moreover, rottlerin, an inhibitor of protein kinase $\delta$, suppressed the upregulation of HO-1 protein production, possibly involving the interaction of NF-E2-related factor 2 (Nrf2), which has a key role as a HO-1 transcription factor. Acrolein elevated the nuclear translocation of Nrf2 in nuclear extraction. The results suggest that RAW 264.7 may protect against acrolein-mediated cellular damage via the upregulation of HO-1, which is an adaptive response to oxidative stress.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.205-211
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• 2007

This study was designed to investigate the suppressive effect of chlorophyll a on nitric oxide (NO) production and intracellular oxidative stress. In addition, chlorophyll a regulation of nuclear factor (NF) ${\kappa}B$ activation and inducible NO synthase (iNOS) expression were explored as potential mechanisms of NO suppression in a lipopolysaccharide (LPS)-stimulated macrophage cell line. RAW 264.7 murine macrophages were preincubated with various concentrations ($0-10\;{\mu}g/ mL$) of chlorophyll a and stimulated with LPS to induce oxidative stress and inflammatory response. Treatment with chlorophyll a reduced the accumulation of thiobarbituric acid-reactive substances (TBARS), enhancing glutathione level and the activities of antioxidative enzymes including superoxide dismutase, catalase, glutathione peroxidase (GSH-px), and glutathione reductase in LPS-stimulated macrophages compared to LPS-only treated cells. NO production was significantly suppressed in a dose-dependent manner (p<0.05) with an $IC_{50}$ of $12.8\;{\mu}g/mL$. Treatment with chlorophyll a suppressed the levels of iNOS protein and its mRNA expression. The specific DNA binding activities of NFkB on nuclear extracts from chlorophyll a treated cells were significantly suppressed in a dose-dependent manner with an $IC_{50}$ of $10.7\;{\mu}g/mL$. Chlorophyll a ameliorates NO production and iNOS expression through the down-regulation of NFkB activity, which may be mediated by attenuated oxidative stress in RAW 264.7 macrophages.

• Korean Journal of Veterinary Research
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• v.50 no.2
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• pp.113-116
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• 2010

To determine the prevalence of Escherichia (E.) coli O157 : H7 from pigs after the Hazard Analysis and Critical Control Point (HACCP) system has been applied to Korean swine farm since 2006, 291 fecal samples were tested between May and December in 2008. Four E. coli O157:non-H7 (1.4%) were isolated from 4 different non-HACCP-accredited farms and they didn't have virulent genes which can cause illness for human. Also, Clostridium (C.) perfringens, Salmonella spp. and E. coli enterotoxins were tested using multiplex PCR. The positive rate for these pathogens of non-HACCP-accredited farms was higher than that of HACCP-accredited farms, and especially in case of C. perfringens, E. coli enterotoxins LT and STa, it was statistically significant (p < 0.05). Thus, the early implementation of the HACCP program is expected to greatly contribute to the safety of livestock products as well as food hygiene.

• Journal of Photoscience
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• v.7 no.4
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• pp.153-154
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• 2000

No Abstract. See full-text

• Korean Journal of Food Science and Technology
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• v.51 no.3
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• pp.248-257
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• 2019

This study aimed to determine the chemical components of different cultivars (Gabjubaekmok, Sangjudungsi, and Godongsi) of persimmon (Diospyros kaki Thunb.) and the effects of maturity. The detected free sugars were fructose and glucose, and glucose levels tended to increase with maturity. Palmitic acid, oleic acid, linoleic acid and stearic acid, and potassium were major components. In the amino acid component analysis, the following were usually present in the following month: glutamic acid in Gabjubaekmok in July, lysine in Sangjudungsi in August, and threonine in Godongsi in October. Vitamin C tended to increase with aging, and fruit harvested in July had the highest total phenolic and flavonoid contents. In the metabolite analysis, there were significant differences among cultivars and with maturity. The major physiological compounds were analyzed using ultra performance liquid chromatography quadrupole time-of-flight tandem mass ($UPLC/Q-TOF/MS^2$) and were citric acid and gallic aicd. As maturity progressed, citric acid increased but gallic acid decreased.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.7 no.4
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• pp.267-273
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• 2007

This paper presents the implementation of an educational kit for intelligent system control education. Neural network control algorithms are presented and control hardware is embedded to control the inverted pendulum system. The RBF network and the MLP network are implemented and embedded on the DSP 2812 chip and other necessary functions are embedded on an FPGA chip. Experimental studies are conducted to compare performances of two neural control methods. The intelligent control educational kit(ICEK) is implemented with the inverted pendulum system whose movements of the cart is limited by space. Experimental results show that the neural controllers can manage to control both the angle and the position of the inverted pendulum systems within a limited distance. Performances of the RCT and the FEL control method are compared as well.

• Bulletin of the Korean Chemical Society
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• v.35 no.12
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• pp.3502-3508
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• 2014

The first synthetic route to 5'-norcarbocyclic C-nucleoside [7-oxa-7,9-dideazadenosine (furo[3,2-d]pyrimidine) and 9-deazaadenosine (pyrrolo[3,2-d]pyrimidine)] phosphonic acids from commercially available 1,3-dihydroxy cyclopentane was described. The key C-C bond formation from sugar to base precursor was performed using Knoevenagel-type condensation from a ketone derivative. Synthesized C-nucleoside phosphonic acids were tested for anti-HIV activity as well as anti-leukemic activity. Compound 26 showed significant anti-leukemic activity.

• Journal of Life Science
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• v.15 no.6 s.73
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• pp.987-993
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• 2005

A bacterium, producing a fibrinolytic enzyme, was screened from a decaying rice plant. The bacterium was identified as Bacillus subtilis by morphological, biochemical, and physiological properties and named Bacillus subtilis BK-17. The fibrinolytic enzyme (BK) was purified from supernatant of Bacillus subtilis BK-17 culture broth. The molecular weight was 31 kDa as determined by SDS-PAGE. The effect of temperature, pH, and plasminogen on the activity of the bacillokinase (BK) was analysed and the activity was compared with urokinase. The optimal temperature and pH were $50^{circ}C$ and pH 7, pH 8, respectively. The BK activity was inhibited to $45\%$, $35\%$, and $23\%$ with 1mM EDTA, $Zn^{2+}$, and $Ca^{2+}$, respectively. However, $Mg^{2+}$, $Mn^{2+}$, and $Co^{2+}$ ions did not have any significant effect on the enzyme activity The BK showed the artivity in the both plates, plasminogen-free fibrin plate and plasminogen-rich fibrin plate. The result indicates that the BK can directly act the fibrin. In comparison of fibrinolytic activity with urokinase on the fibrin plate, the BK shows about 20 folds higher activity than that of the urokinase.

• Korean Journal of Environmental Agriculture
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• v.42 no.4
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• pp.382-388
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• 2023

A liquid-type chlorella (LC) produced by self-cultivation is used for strawberry cultivation by farmers in Korea. This study aimed to investigate seedling growth in two strawberry cultivars 'Soraya' and 'Haruhi' after applying solid-type chlorella (SC) in the greenhouse for 30 d. The treatments were as follows: Control, LC (0.2% of 1.0 × 10⁷ cells/mL), ¼ SC (12.5 g/m²), ½ SC (25 g/m²), and SC (50 g/m²). Compared to the control, in the ½ SC treatment, dry weight of the seedlings increased at 30 days after treatment (DAT). Phosphorus content in the leaves of 'Soraya' seedlings of the SC treatment increased compared to that of the control. At 10 and 30 DAT, photosynthetic pigments including chlorophylls and carotenoids in the seedlings of both cultivars increased with the ½ SC treatment. These results indicate that the application of SC improved the growth of strawberry seedlings and could replace LC.

• Proceedings of the Korean Magnestics Society Conference
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• 2007.05a
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• pp.190.1-190.1
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• 2007