• Journal of Food Hygiene and Safety
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• v.28 no.2
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• pp.138-145
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• 2013

This study was conducted to evaluate the microbiological contamination on commonly used hand towels in the child care centers and to investigate the toxin gene and toxin production ability of food-borne pathogens. A total of 22 commonly used hand towels including 7 for before use and 15 for during use were tested. The average number of total aerobic bacteria and fungi were 6.2 log CFU/100 $cm^2$ and 4.1 log CFU/100 $cm^2$. Coliform bacteria were detected in 4 out of 7 before used towels (57.1%) and all of during used towels (100%). These results showed that the sanitary conditions of hand towels in the child care centers should be improved promptly. Among the pathogenic bacteria, Staph. aureus and B. cereus without Salmonella spp. were detected in 5 (22.7%) and 11 (50.0%) out of 22 hand towels. All of Staphy. aureus isolated in this study did not possess any toxin genes and did not produce enterotoxin. The detection rate of hblC, hblD, and hblA toxin genes in B. cereus was 72.7, 72.7, and 54.5% respectively. The possession rate of nheA, nheB, and nheC toxin genes showed 81.8, 72.7, and 54.5% respectively. The cytK and entFM toxin genes were presented at 45.5 and 90.0% in B. cereus. The HBL was detected in 8 out of 11 B. cereus isolates (72.7%) and 5 B. cereus isolates produced NHE (45.5%). Ten out of eleven B. cereus isolates (90.9%) produced one or more enterotoxin such as HBL and NHE. From the results, using a private hand towel or paper towel is required to prevent the cross-contamination between commonly used hand towel and children's hands in the child care center.

• Proceedings of the Korean Magnestics Society Conference
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• 1996.10a
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• pp.100-101
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• 1996

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.2
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• pp.189-197
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• 2014

This work proposes a 12b 100 MS/s $0.11{\mu}m$ CMOS three-step hybrid pipeline ADC for high-speed communication and mobile display systems requiring high resolution, low power, and small size. The first stage based on time-interleaved dual-channel SAR ADCs properly handles the Nyquist-rate input without a dedicated SHA. An input sampling clock for each SAR ADC is synchronized to a reference clock to minimize a sampling-time mismatch between the channels. Only one residue amplifier is employed and shared in the proposed ADC for the first-stage SAR ADCs as well as the MDAC of back-end pipeline stages. The shared amplifier, in particular, reduces performance degradation caused by offset and gain mismatches between two channels of the SAR ADCs. Two separate reference voltages relieve a reference disturbance due to the different operating frequencies of the front-end SAR ADCs and the back-end pipeline stages. The prototype ADC in a $0.11{\mu}m$ CMOS shows the measured DNL and INL within 0.38 LSB and 1.21 LSB, respectively. The ADC occupies an active die area of $1.34mm^2$ and consumes 25.3 mW with a maximum SNDR and SFDR of 60.2 dB and 69.5 dB, respectively, at 1.1 V and 100 MS/s.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.17 no.1
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• pp.27-31
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• 2006

Objectives : We examined whether D8/17 expression in Tourette syndrome children who suggested PANDAS were higher than comparison group, and there was my clinical difference by D8/l7 expression. Methods : Nine Tourette's syndrome children suggested PANDAS and two ADHD children without tic disorder were evaluated far percentage of D8/17 expression-positive B cells by immunofluorescence flow cytometric assay and anti-streptolysin O titer. Results : The frequency of D8/17 positive B lymphocyte rate was significantly higher in Tourette's syndrome than ADHD, whose average rate were 77.9 and 24.8, respectively. Among 9 TD patients,4 patients showed above 90% D8/l7 expression. There was high concordance expression rate between mother (98.4%) and daughter (99.0%) The significant relation between percentage of D8/17 expression and tic severity were not detected. The significant relation between percentage of D8/17 expression and anti-streptolysin O titer were not detected, however in 66.7% TD patients showed above 100IU/ml. Conclusion : We concluded that subgroup of TD children are streptococcal infected tic disorder, so called PANDAS.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.31 no.4 s.54
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• pp.305-310
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• 2005

To obtain effective and safe depigmenting agents, we investigated the effects of Scirpi rhizoma, a medicine among Chinese herbs, on melanogenesis. Dried S. rhizoma was refluxed with 70% aqueous ethanol and the extract was evaporated to dryness. To determine the effects as a whitening agent, various in vitro tests were performed such as free radical scavenging activity, melanin formation assay, tyrosinase activity and expression of tyrosinase, TRP-1 and TRP-2(western blot and RT-PCR) in B16 melanoma cells. S. rhizoma showed scavenging activities of free radicals and reactive oxygen species (ROS) with the $IC_{50}\;of\;638{\mu}g/mL$ against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and $21.7{\mu}g/mL$ against superoxide radicals in the xanthine/xanthine oxidase system, respectively. S. rhizoma significantly inhibited melanin production in B16 melanoma cells. S. rhizoma treatment(48 h) suppressed the biosynthesis of melanin up to 27% at 100{\mu}g/mL$ and reduced tyrosinase activity up to 31% at $100{\mu}g/mL$ in B16 melanoma cells. S. rhizoma was also able to significantly inhibit tyrosinase and TRP-1 expression in protein and mRNA level. These results suggest that S. rhizoma inhibited melanin biosynthesis by regulating tyrosinase activity and expression in B16 melanoma cells. Therefore, S. rhizoma may be useful as a new antioxidant and whitening agent to inhibit melanogenesis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.4
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• pp.532-539
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• 2015

Inhibition of osteoclast differentiation is the most important target for prevention of inflammatory bone resorption and bone diseases. Here, we investigated the effect of spinach ethanol extract on osteoclast differentiation in RAW264.7 cells. Spinach was extracted with ethanol at a concentration ranging from 0 to 100% (0, 25, 50, 75, and 100% ethanol). Inhibitory effects of receptor activator of NF-${\kappa}B$ ligan (RANKL)-induced osteoclast differentiation were evaluated using tartrate-resistant acid phosphatase (TRAP) stain assay. The most effective eanol concentration for osteoclast differentiation was 100%. Spinach extract (100% ethanol) suppressed RANKL-induced osteoclast differentiation and TRAP activity. Spinach extract (100% ethanol) also suppressed expression of osteoclast differentiation-related marker genes (NFATc1, c-FOS, cathepsin K, and TRAP) and down-regulated RANKL-induced NF-${\kappa}B$ and ERK phosphorylation during osteoclast differentiation. Taken together, our results suggest that spinach extract is effective against reducing osteoclast differentiation through the NF-${\kappa}B$-mediated pathway.

• Journal of Food Hygiene and Safety
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• v.21 no.1
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• pp.41-46
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• 2006

This study was carried out to survey the prevalence of foodborne pathogens in Sangshik products and their raw materials far the purpose of ensuring safety of those products in market, and establishing microbial regulatory standard. From 2002 to 2004, a total of 191 Sangshik products were purchased from market or mail-order sales, and major foodborne pathogens; E. coli, Salmonella, Staphylococcus aureus, Bacillus cereus, Clostridium perfringens, Listeria monocytogenes, Campylobacter jejuni, Yersinia enterocolitica, E. coli O157:H7, Vibrio parahaemolyticus were tested. B. cereus, C. perfringens and E. coli were detected from 29 samples (15.2%), 21 samples (11.0%) and 1 sample (0.5%), respectively. But other tested bacteria were not detected. For the identification of contamination source, 53 Sangshik ingredients were collected from 9 different manufacture factories. The results were similar with the Sangshik products. Aerobic plate counts were ranging from $1.0X10^3cfu/g\;to\;1.5X10^8cfu/g$. B. cereus was detected from 13 samples (24.5%), and counted as less than 100 cfu/g. C. perfringens were detected from 2 samples (3.8%), and counted as less than 100 cfu/g. Other foodborne pathogens were not detected except for B. cereus and C. perfringens. From the results, it was revealed that potential of microbial hazard by Sangshik was relatively low. However, it would be suggested that hygienic management and controling be needed for the prevention of growing contaminated pathogens and cross contamination during process and sale due to improper storage and management.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.4
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• pp.698-703
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• 1994

In spore rec-assay using B. subtillus H17(rec) and M 45(rec) , the ethanol extract of buckwheat leaves showed antimutagenicity in condition of low concentrations, but its did comutagenicity in condition of high concentrations. In Ames test, the ethanol extract of buckwheat leaves reduced the mtabenicity of N-methyl-N' -nitro-N-nitrosoguaidine (MNNG), benzo (a) pyrene(B($\alpha$)P), 2-amino-fluorene(2AF), and 3-amino -1, 4-dime-thyl-5-H-pyrido(4, 3-b) indol(Trp-P-1) in Salmonella typhimurium TA98 and TA100. The ethanol extract was fractionated by hexane, ethylacetate, butanol and water. Among Them hexane fraction showed the highest inhibition rate on the mutagenicity of B($\alpha$)P, and so did chloroform fraction on the mutagenicity of MNNG in S. typhimurium Ta98 and TA100. To elucidate the antimutagenic mechanism of the ethanol extract, it was mixed and co-incubated with various metagens, S9 mix, and the bacteria with different experimental orders and different reaction times. The ethanol extract did not affect reversion rate of pre-mutated. S.typhimurium. However, when the ethanol extract was added to the mutagens before their interaction with S.typhimurium , it reduced the mutation rate to 152$\pm$12-273$\pm$18 colonies/plates in case of MNNG, and 135$\pm$13-195$\pm$10 colonies/ plates in case of B($\alpha$)P), showing strong desmutagenic activity.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.227-228
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• 2006

In this paper, we introduce the design and fabrication of 60 GHz low noise amplifier MMIC for IEEE802.15.3c WPAN system. The 60 GHz LNA was designed using ETRI's $0.12{\mu}m$ PHEMT process. The PHEMT shows a peak transconductance ($G_{m,peak}$) of 500 mS/mm, a threshold voltage of -1.2 V, and a drain saturation current of 49 mA for 2 fingers and $100{\mu}m$ total gate width (2f100) at $V_{ds}$=2 V. The RF characteristics of the PHEMT show a cutoff frequency, $f_T$, of 97 GHz, and a maximum oscillation frequency, $f_{max}$, of 166 GHz. The performances of the fabricated 60 GHz LNA MMIC are operating frequency of $60.5{\sim}62.0\;GHz$, small signal gain ($S_{21}$) of $17.4{\sim}18.1\;dB$, gain flatness of 0.7 dB, an input reflection coefficient ($S_{11}$) of $-14{\sim}-3\;dB$, output reflection coefficient ($S_{22}$) of $-11{\sim}-5\;dB$ and noise figure (NF) of 4.5 dB at 60.75 GHz. The chip size of the amplifier MMIC was $3.8{\times}1.4\;mm^2$.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.156-161
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• 1991

The mutagenic, comutagenic and antimutagenic effects of red pepper powder were studied by using Ames mutagenicity test. extracts(3 fractions) of the red pepper powder did not show any mutagenicity with or without S9 mix in Salmonella typhimurium strains of TA100 and TA98. These extracts did not show any comutagenicity on N-methyl-N'-nitro-N-nitrosoguanidine(MNNG). Capsaicin also did not exhibit any mutagenicity in the absence or presence of S9 mix prepared from rat or hamster livers. However, the red pepper powder showed antimutagenicity aganist aflatoxin $B_1(AFB_1)$ mediatdd mutagenicity. Especially first fraction of the pepper powder inhibited strongly the mutagenicity of $AFB_1$. There was no difference of these activities between hotter tasted pepper powder and plain hot tasted pepper powder.