• Journal of Gastric Cancer
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• 제2권2호
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• pp.63-68
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• 2002

위의 parietal cell 혹은 대식세포와 유사한 세포 내부에서 H. pylori가 발견된다는 보고가 있기는 하나 일반적으로 H. pylori는 Shigella와 같은 침습성 세균은 아닌 것으로 알려져 있다. 그럼에도 불구하고 H. pylori에 감염된 위점막에는 많은 수의 호중구를 위시한 염증세포의 침윤이 관찰되는데 H. pylori가 위상피세포에 부착할 경우 위상피세포를 자극하여 interleukin-8을 위시한 cytokine을 발현케하고 이에 의하여 호중구 등의 염증세포가 몰려들게 된다. 한편 고유층에 몰려든 호중구에서는 다시 interleukin-8을 위시한 일련의 호중구 활성화 chemokine을 분비하여 염증반응을 증폭해 나갈 것이다. 호중구에서 발현되는 myeloperxidase나 활성산소 등도 위점막의 조직 손상에 기여할 것이다. 위상피세포를 덮고 있는 점액층은 위상피세포를 보호한다고 알려져 있으나 H. pylori 감염의 경우 점액층에 의하여 H. pylori의 운동성이 증가하고 이것이 위상피세포로부터의 cytokine 발현을 자극하여 염증반응을 증폭하는 데 관여할 가능성도 있다. H. pylori는 위상피세포에 대하여 apoptosis를 유도함과 동시에 고유층에 몰려든 호중구에 대하여는 apoptosis를 억제케하여 궁극적으로 염증반응을 증폭 및 지속시켜 나가는 쪽으로 작용한다. 한편 H. pylori는 위상피세로로부터 COX-2의 발현을 증가시키는데 이는 위상피세포의 APOPTOSIS를 억제하는 방향으로 작용한다. 이외에 H. pylori의 urease에 의하여 발생한 암모니아나 H. pylori 자신이 분비하는 세포독소가 세포 손상을 유발할 가능성도 있다. 상술한 여러 독성 인자들 중 어느 하나가 단독으로 작용하기보다는 여러 인자가 같이 동시에 또는 시차를 두고 작용할 가능성이 많다고 생각된다.

• Journal of Preventive Medicine and Public Health
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• 제38권2호
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• pp.117-124
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• 2005

Before twentieth centuries and during early twentieth centuries, communicable diseases were the major cause of morbidity and mortality in Korea. But reliable data are not available. After 1975, the overall morbidity and mortality from communicable diseases, rapidly declined. Recently many new pathogenic microbes were recognized: L. monocytogenes, Hantaan virus, Y. pseudotuberculosis, P. multocida, L. pneumophilia, Human immunodeficiency virus (HIV), G. seoi, H. capsulatum, C. burnetii, V. cholerae O139, C. parvum, F. tularensis, E. coli O157:H7, B. burgdorferi, S. Typhimurium DT104, Rotavirus, hepatitis C virus and so on. Since the first HIV infection recognized in 1985, the reported cases of infection and deaths from HIV/AIDS have been steady increased each year. Legionnaire's disease, E. coli O157:H7 colitis, listeriosis and crytosporidiasis have been occurring just sporadically among immunocompromized cases. Many re-emerging communicable diseases were occurred in Korea: leptospirosis, malaria, endemic typhus, cholera, tsutsugamushi disease, salmonellosis, hepatitis A, shigellosis, mumps, measles, acute hemorrhagic conjunctivitis, brucellosis and so on. Leptospirosis and tsutsugamushi diseases have been noticed as major public health problems since 1980s. The malaria that had been virtually disappeared for a decade has reappeared from 1993 with striking increase of patients in recent 3-4 years. The distributions of salmonella and shigella serotypes have been changed a lot in recent few decades. Furthermore rapid emergence of antibiotic-resistant bacterial strains induces more difficult and complex problems in control of communicable diseases. We must recognize on the importance of environment and ecosystem conservation and careful prescription of anti-microbial agent in order to prevent communicable diseases.

• 한국축산식품학회지
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• 제40권2호
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• pp.172-182
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• 2020

In the present study, we determined the degree of hydrolysis (DH) of porcine blood plasma proteins, albumin, and globulin hydrolyzed by six proteases (alcalase, neutrase, flavourzyme, protamex, trypsin, and papain) for various reaction times. Moreover, antimicrobial activities of hydrolysates against five pathogenic microorganisms (Bacillus cereus, Staphylococcus aureus, Salmonella Typhimurium, Escherichia coli, and Shigella flexneri) were investigated. Alcalase, trypsin, and papain hydrolysates of the three porcine blood proteins showed higher DH values than hydrolysates produced by the other three proteases. DH of the three porcine blood proteins hydrolyzed by the six proteases failed to increase after 2 h of hydrolysis. In antimicrobial tests, hydrolysates (hydrolysis time of 2 h) showed antibacterial activity only against B. cereus. Albumin hydrolysates showed higher antimicrobial activity than globulin and plasma hydrolysates. Albumin hydrolysates obtained with flavourzyme, protamex, and trypsin showed higher antimicrobial activity than those obtained with the other three proteases.

• 대한의생명과학회지
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• 제8권1호
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• pp.29-37
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• 2002

Listeria monocytogenes poses an increasing health risk, which in part is due to increasing health risk, consumption of ready-to-eat food products and the introduction of increasing numbers of food products from regions with different dietary habits. L. monocytogenes can be present in meat, shellfish, vegetables, unpasteurised milk and soft cheese and poses a risk if food containing these products is stored at refrigeration temperature and is not properly heated before consumption, as L. monocytogenes is psychrophilic. Amplified-fragment length polymorphism (AFLP) analysis is the method of genotypic techinique in which adaptor oligonucleotides are ligated to restriction enzyme fragments and then used as target sites for primers in a PCR amplification. The amplified fragments are electrophoretically separated to give strain-specific band profiles. Single-enzyme approach that did not require costly equipment or reagents for the fingerprinting of strains of Listeria monocytogenes was developed. Single-enzyme amplified fragment length polymorphism (SE-AFLP) analysis was used to perform species and strain identification of Salmonella, Shigella, Yersinia and E. coli. By careful selection of AFLP primers, it was possible to obtain reproducible and sensitive identification to strain level. The AFLP patterns of L. monocytogenes are divided by the kinds of specimens in which were isolated. SE-AFLP fragments can be analyzed using standard gel electrophoresis, and can be easily scored by visual inspection, due to the low complexity of the fingerprint obtained by this method. These features make SE-AFLP suitable for use in either field or laboratory applications.

• 한국식품조리과학회지
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• 제26권2호
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• pp.206-213
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• 2010

In this study, the antibacterial activities of essential oil from Zanthoxylum schinifolium against four Gram-positive bacteria and six Gram-negative bacteria were investigated. The antibacterial activity of the oils was determined using the agar-well diffusion assay, MIC (minimum inhibitory concentration) and MBC (minimum bactericidal concentration). In particular, essential oil from Z. schinifolium showed higher antibacterial activity against Gram-positive bacteria than against Gram-negative bacteria. Essential oil from Z. schinifolium displayed large inhibition zones especially against Bacillus cereus (31 mm). At concentrations between 0 and $20\;{\mu}g/mL$ the oils showed an antibacterial effect against both Gram-negative and Gram-positive bacteria. The minimum inhibitory concentration (MIC) values against nine bacteria ranged from 1.25 to $5\;{\mu}g/mL$. The minimum bactericidal concentration (MBC) values against eight bacterial ranged from 2.5 to $20\;{\mu}g/mL$, except Shigella sonnei. Furthermore, our finding on the antibacterial activities of essential oils from Zanthoxylum schinifolium validated the use of this plant for medical purposes.

• Food Science and Biotechnology
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• 제16권4호
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• pp.615-620
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• 2007

Commercially packed kimchi products from 6 different manufacturers, which are exported overseas as well as sold domestically, were analyzed to determine their microorganism distributions and presence of pathogenic bacteria. All samples showed decreasing pH levels (from 5.7-6.2 to 3.9-4.3) and increasing titratable acidities (from 0.3-0.4 to 0.8-1.2%) during 15 days of storage at $4^{\circ}C$. Total bacterial counts ranged from $2.1{\times}10^5-1.9{\times}10^6\;CFU/mL$ in the initial kimchi samples, and then increased to $1.1{\times}10^8-1.8{\times}10^9\;CFU/mL$. The coliform numbers decreased from approximately $2.5{\times}10^2-1.7{\times}10^4\;CFU/mL$ to zero. Major foodborne pathogens such as Salmonella spp., Staphylococcus aureus, Escherichia coli O157:H7, Listeria monocytogenes, Bacillus cereus, Yersinia enterocolitica, and Shigella spp. were not detected in any of the samples. However, 2 out of the 6 samples carried E. coli, emphasizing the need for improved hygiene practice. Interestingly, Hafnia alvei, belonging to the Enterobacteriaceae family, was isolated in all of the samples. Further study is needed on this newly reported bacterium in kimchi.

• 한국식품과학회지
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• 제52권3호
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• pp.244-248
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• 2020

To retain valuable resources, organisms adopt several strategies including coprophagy. Cells covering the outer skin and internal digestive lumen are actively recycled to maintain their integrity. In present study, we suggested that the small intestine can consume dead cells in a manner similar to how it consumes protein from the diet. We examined the eluates from five segments of the mouse small intestine and cecum and 2 segments of the large intestine and small intestine tissue, and detected immunoreactivity with eukaryotic caveolin-1 and β-actin antibodies only in the cecum and 2 segments from the large intestine. Bacterial agitation of the mouse intestine with Shigella disrupted the architecture and absorptive function of the small intestine. Small intestine eluates were immunoreactive with murine caveolin-1 and contained heme as determined by dot blot analysis. We concluded that the body conserves resources in the small intestine by disposing of and recycling shedded cells.

• 대한임상검사과학회지
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• 제36권1호
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• pp.1-6
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• 2004

The enterobacterial repetitive intergenic consensus (ERIC)-PCR is a recently described DNA fingerprinting technique based on amplification of repetitive element distributed in bacteria. We applied of ERIC-PCR to clinical isolates of Vibrio parahaemolyticus and other bacteria associated diarrhea. Twenty isolates of V. parahaemolyticus were used for intragenic genotyping, which were isolated from 2001 to 2002 in Chungbuk National University hospital. For interspecies genotyping, V. vulnificus, V. alginolyticus, V. parahaemolyticus, Escherichia coli, Salmonella and Shigella spp. were used. The genotyping were analyzed by ERIC-PCR. The genotyping of V. parahaemolyticus were grouped two major pattern (A, B) and were subdivided into 10 subtypes (A1, A2, B1-B8) by ERIC-PCR. These method distinctly differentiated bacterial species associated diarrhea. Those results show that ERIC-PCR can be reliable and efficient method for genotyping of V. parahaemolyticus and bacteria associated diarrhea.

• 한국어병학회지
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• 제1권2호
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• pp.95-101
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• 1988

During the period from August through October, 1988, 50 isolates of Edwardsiella tarda were isolated from 6 diseased cultured Channa argus in Dunchi island and Myung-ghi, near Pusan in Korea were examined by studying their biochemical and antibiotical reactions. The ill animals moved slowly and irregular-formed swimming at the surface of the corner. The symthoms were necrosis with hemorrhage on the body surface, head, gill region, and mouth. Some fish were observed dropsy of the belly. The bacteria grew slowly on Double Salmonella-Shigella agar, 24h, at $37^{\circ}C$ to form relatively small size (2mm diameter), smoothed and convexed form with transient or black in center of the colonis. They gave negative reactions to Voges-Proskauer, Simmon's citrate, urea, KCN (in growth), gelatin, arginine dehydrolase, phenylalanine deaminase and many sugars. The isolates showed positive reactions to $H_2S$ (in KIA agar), indol, Methyl-Red, motility, lysine and ornithine decarboxylase, and gas from glucose. 8 drugs tested as chloramphenicol, colistin, gentamicin, kanamycin, lincomycin, nalidixic acid spectinomycin, and tetracycline. All cultures were resistant to colistin, lincomycin and spectinomycin respectibly, but sensitive to kanamycin and nalidixic acid. Three strains showed resistance to chloramphenicol and 2 isolates among them were resistant to two drugs(gentamicin and tetracycline), coincidentally.

• Mycobiology
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• 제35권1호
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• pp.25-29
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• 2007

A newly synthesized Nickel (II) tyrosine complex was screened as potential antimicrobial agent against a number of medically important bacteria (Bacillus subtilis, Streptococcus ${\beta}$-haemolytica, Escherichia coli, Shigella dysenterae) and fungi (Aspergillus fumigatus, Candida albicans, Aspergillus niger, Aspergillus flavus, Penicillium sp.) strains. were used for antifungal activity. The antimicrobial activity was evaluated using the Agar Disc method. Moreover, the minimum inhibitory concentration of the complexes was determined against the same pathogenic bacteria and the values were found between $4{\sim}64\;{\mu}g\;ml^{-1}$. Brine shrimp bioassay was carried out for cytotoxicity measurements of the complexes. The $LC_{50}$ values were calculated after probit transformation of the resulting mortality data and found to be 6 ${\mu}g\;ml^{-1}$.