• Food Science and Preservation
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• v.16 no.6
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• pp.965-970
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• 2009

PCR technology has been widely used to detect and quantify microbial pathogens in foodstuffs, because the technique is rapid, sensitive, and selective. In this study, detection of contaminating pathogenic bacteria on shells of chicken eggs was performed using both a commercial multiplex polymerase chain reaction (PCR) kit and a viable count method employing a selective medium. The PCR kit was capable of detecting Campylobacter jejuni, Escherichia coli O157:H7, Staphylococcus aureus, Bacillus cereus, Vibrio parahaemolyticus, Listeria monocytogenes, Yersinia enterocolitica, Salmonella species, and Shigella species. Using the PCR method, five bacterial species were detected from 30 samples (33.3%) of 90 batches of eggs commercially available in a market. PCR products from B. cereus, S. aureus, L. monocytogenes, Y. enterocolitica, and E. coli O157:H7 were detected, and the numbers and frequencies of positive samples were 17 (18.8%), 12 (13.3%), 15 (16.6%), 16 (17.7%),and 4 (4.4%), respectively. None of any Salmonella species, C. jejuni, V. parahaemolyticus, or Shigella species was detected in this study. The results of PCR testing were confirmed using a typical viable count method employing a selective medium. We suggest that the multiplex polymerase chain reaction (mPCR) assay is a rapid and reliable method for detection of pathogenic bacteria contaminating eggs.

• The Journal of the Korean Society for Microbiology
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• v.15 no.1
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• pp.47-54
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• 1980

Exoenzymes, protease(P) and elastase(E) produced by Pseudomonas aeruginosa are reported to have close relationship with pathogenicity of Pseudomonas aeruginosa. Productibility of exoenzymes P and E were studied and compared in environmental isolates from hospital environments and clinical isolates from various clinical specimens, also, the relationship between their enzyme production and serotype were reviewed. 1. Clinical isolates were typed into nine serotypes A, B, C, D, E, F, G, H and I. Serotype E had the highest incidence of 24%, followed by B with 16.8%, G, 15.1% and C, 9.3%. 2. Environmental isolates were, typed as serotype B, C, E, F, G, H, I, K and M. Serotype I had the highest incidence of 26.6%, followed by C, F and M each incidence of 14.3%. 3. In the typing of the above two groups, serotypes A and D were found only in the clinical isolates and serotypes K, and M were found only in the environmental isolates. Serotypes J and L were found in neither clinical isolates nor environmental isolates. 4. In the distribution of serotypes from various clinical specimens, serotype G among isolates from pus showed incidence of 20.4%, and serotypes E and B were 19.5% separately. Serotype E had incidence of 22.6% and 20.0% in urine and sputa respectively, showing a high rate compared to the other serotypes. 5. The incidence of strains producing both exoenzymes P and E was 77.8% in the preserved strains of clinical isolates and 76.2% in the environmental isolates. There were no significant difference between the two groups. 6. Serotypes A and H, which are preserved strains from clinical isolates showed productibility of both exoenzymes P and E, the other serotypes showed productibility of various combination of exoenzymes. Among the environmental isoaltes, production of both exoenzymes P and E were seen in serotypes E, F, G, H, I and K and no serotype produced only P or E. 7. In ability to produce exoenzymes of isolates from sources of various clinical specimens, strains producing both exoenzymes P and E were found most frequently in pus with incidence rate of 82.0%, followed by 80.0% in sputum and urine. 8. Almost all the fresh strains of clinical isolates were producers of both exoenzymes P and E.

• Korean Journal of Clinical Laboratory Science
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• v.53 no.3
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• pp.217-224
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• 2021

Fluoroquinolone (FQ) resistant gram-negative pathogens have emerged worldwide, and the recent increase in FQ resistant Escherichia coli is of great concern in Korea. This study investigated FQ resistance determinants and the epidemiological relationship of 56 ciprofloxacin-resistant E. coli isolated from a tertiary hospital in Daejeon, South Korea from June to December 2018. Molecular epidemiology was investigated by multilocus sequence typing (MLST). Polymerase chain reaction (PCR) and sequence analysis were performed to identify chromosomal mutations in the quinolone resistance determining regions (QRDR) of gyrA, gyrB, parC, and parE and to describe the occurrence of the following plasmid-mediated quinolone resistance (PMQR) genes: aac(6)-Ib-cr, qepA, qnrA, qnrB, qnrC, qnrD, and qnrS. MLST analysis showed 12 sequence types (STs) and the most prevalent ST was ST131 (31/56, 55.4%), followed by ST1193 (13/56, 23.2%), and ST405 (3/56, 5.4%). In 56 ciprofloxacin-resistant E. coli isolates, Ser83→Leu and Asp87→Asn in gyrA and Ser80→Ile and Glu84→Val in parC (51.8%, 29/56) were the most frequent amino acid substitutions and aac(6)-Ib-cr (33.9%, 19/56) was the most common PMQR gene. These results of FQ resistance determinants were more frequently observed in ST131 compared with other clones. Continuous monitoring of the epidemiological characteristics of ciprofloxacin-resistant E. coli isolates and further investigation of FQ resistance determinants are necessary.

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.156.1-156.1
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• 2007

• Tuberculosis and Respiratory Diseases
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• v.79 no.4
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• pp.295-301
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• 2016

Background: Specific immunoglobulin E (IgE) sensitization to staphylococcal enterotoxin (SE) has been recently considered to be related to allergic disease, including asthma. Despite studies on specific IgE (sIgE) to SE and its relationship to asthma diagnosis and severity, the association of sIgE to SE with airway hyperresponsiveness (AHR) remains unclear. Methods: We enrolled 81 asthma patients admitted to the Severance Hospital in Korea from March 1, 2013, to February 28, 2015 and retrospectively reviewed the electronic medical records of the enrolled subjects. The serum levels of sIgE to SE (A/B) of all subjects was measured using the ImmunoCAP 250 (Phadia) system with SE-sIgE positive defined as >0.10 kU/mL. Results: The SE-sIgE level was not significantly correlated with asthma severity (forced expiratory volume in 1 second [$FEV_1$], $FEV_1$/forced vital capacity, sputum eosinophils, and serum eosinophils), whereas the SE-sIgE level in patients with positive AHR ($mean{\pm}standard$ error of the mean, $0.606{\pm}0.273kU/mL$) was significantly higher than that in patients with negative AHR ($0.062{\pm}0.015kU/mL$, p=0.034). In regression analysis, SE sensitization (sIgE to SE ${\geq}0.010kU/mL$) was a significant risk factor for AHR, after adjustment for age, sex, $FEV_1$, and sputum eosinophils (odds ratio, 7.090; 95% confidence interval, 1.180-42.600; p=0.032). Prevalence of SE sensitization was higher in patients with allergic rhinitis and non-atopic asthma patients, as compared to patients without allergic rhinitis and atopic asthma patients, respectively, but without statistical significance. Conclusion: SE sensitization is significantly associated with AHR.

• Korean Journal of Agricultural Science
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• v.40 no.1
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• pp.27-34
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• 2013

To investigate the distribution of psychrotrophic bacteria, raw milk was collected from farms in nine different regions located around Kyunggi province in South Korea at four different seasons. Psychrotrophic counts were higher in winter than in other seasons as $3.0{\times}10^4$ CFU/mL (p<0.05). Among nine regions, the population in raw milk sampled from B region was in significantly greater numbers and those from C and D province were in significantly lower numbers than any other regions, $2.4{\times}10^5$ CFU/mL and $8.7{\times}10^3$ CFU/mL, respectively (p<0.05). In addition, among 706 bacterial isolates, the predominant class was Gamma-proteobacteria (81.02%) and genus was Pseudomonas (32.34%), especially Pseudomonas fluorescens (39.46%). Compared to the regional predominance, Acinetobacter johnsonii in A region, Pseudomonas fluorescens in B region, Enterobacter amnigenus in C region, Psychrobacter maritimus in D region, Acinetobacter johnsonii in E region, Acinetobacter haemolyticus in F region, Pseudomonas fluorescens in G region, Acinetobacter jounsonii in H region, and Pseudomonas mucidolens in I region were found.

• 한국해양학회지
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• v.26 no.2
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• pp.108-116
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• 1991

A production model was constructed by combining the production rate and biomass of Sargassum confusum measured at monthly intervals on the coast of Ohori, Korea, to estimate the algal production for a given period. The production for a certain period, e.g., for a year (P/SUB yr/), was calculated from the equation: P/SUB yr/ = .int.P/SUB t/$.$B/SUB t/dt, where pl and Bl are the production rate and biomass at time t. P/SUB l/ was considered as a function of temperature and light. Photosynthesis-Irradiance curves obtained from the in situ experiments were applied for P/SUB l/ Temperature and light intensity can be expressed as periodic functions of time (T, L=f(t)). Diurnal values of water temperature and light intensity at 3 m depth where S. confusum mainly found were substituted into the equation of P/SUB l/. Simulations using our models show that temperature was one of the most sensitive factors operating on the primary production. Thirty percent decrease of light intensity by cloud cover was estimated to decrease the annual production by 5%.

• The Journal of the Acoustical Society of Korea
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• v.24 no.1
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• pp.43-51
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• 2005

In this paper, we propose an algorithm that improves a tone quality of a noisy audio signal in order to enhance a Performance of perceptual filter using noise energy control. Most of the algorithms which were proposed by the other researchers usually applied a filter using the noise energy acquired from a silent range. In this case. the improvement rate of tone quality decreases if the noise energy is changed by the magnitude or environment variation in a signal frame. But the Proposed method Provides the means to find a food estimated noise through energy control of the estimated noise which is obtained from a silent range. Also we can get the enhancement of tone qualify in low frequency band unlike other methods. To show the performance of the Proposed algorithm, various input signals which had a different signal-to-noise ratio (SNR) such as 5dB, l0dB, 15dB and 20dB were used to test the proposed algorithm. With the proposed algorithm, we could confirm the enhancement of tone quality in terms of segmental SNR (SSNR). noise-to-mask ration (NMR) and mean opinion score (MOS) test.

• Korean Journal of Plant Taxonomy
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• v.51 no.3
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• pp.294-304
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• 2021

Given that the Korean genus Elymus L. (Poaceae) is often confused with Agropyron Gaertn., the categories and characteristics of Elymus s.l. have been reviewed morphologically. Two unrecorded taxa of Elymus, E. humidus (Ohwi & Sakam.) T. Osada and E. shandongensis B. Salomon, not previously recorded in Korean flora to date, we report here as an unrecorded species based on samples collected from Chungcheongbuk-do, Gyeongsangnam-do, Jeollanam-do, and Jeollabuk-do. E. humidus is distinguished from other taxa in terms of its habitat around riversides, erect inflorescences, spikelets appressed to rachides of inflorescence, and new individuals asexually propagated at the lower nodes of aerial stems. E. shandongensis is similar to E. tsukushiensis var. transiens (Hack.) H. Osada but is distinguished by the flowering time, slightly curved inflorescences, number of veins of the glumes, and spikelets appressed to the rachides. Descriptions of the two unrecorded Korean taxa, photographs, and keys to neighboring taxa are presented.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.1
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• pp.79-83
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• 2004

In order to investigate the beneficial effects of parsely (Petroselinurn sativum) extract on skin, we measured the synthesis of total collagen and type I procollagen in cultured normal human fibroblast (NHF), the synthesis of prostaglandin E$_2$(PCE$_2$), interleukin 1 ${\alpha}$(IL -1 ${\alpha}$) and tumor necrosis factor ${\alpha}$ (TNF ${\alpha}$) in HaCaT cell and we also measured dermal thickness and density in hairless mouse (Female albino hairless mice, Skh:hr-1). As the results, the synthesis of total collagen and type I procollagen were increased 23％ and 18％ respectively, after 1 $\mu\textrm{g}$/mL parsley extract treatment. The producions of PGE$_2$ induced by UVB irradiation were decreased 60％ after 1 $\mu\textrm{g}$/mL parsley extract treatment. The treatment with 1 $\mu\textrm{g}$/mL parsley extract also decreased the synthesis of IL -1 ${\alpha}$ and TNF ${\alpha}$ induced by 10 uM RA, 100 $\mu\textrm{g}$/mL SLS and 30 mJ/$\textrm{cm}^2$ UVB irradiation, After 4 days treatment with 1％ parsley extract, the dermal thickness of hairless mouse was increased 1.5 times and the density of dermis was tighter than control. These results indicate that parsley extract have anti-aging and anti-irritation effects on skin.