• Toxicological Research
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• 제20권3호
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• pp.179-185
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• 2004

Helicobacter pylori (H. pylori) infects more than half of the people in the world as a major microbe to cause most of gastric diseases. Recently, cytotoxin associated-antigen A (CagA) is believed as one of the most important virulence factors of H. pylori. Molecular toxicological pathway of CagA is necessary to investigate for understanding the pathological and toxicological aspects of H. pylori, since this virulence protein harasses intercellular processes of host cells to get profit for the survival of H. pylori. CagA is coded from cag pathogenicity island (cag PAI) and translocated into host cells by Type 4 secretion system (TFSS). Tyrosine phosphorylation of CagA targets Src homology 2-containing phosphotyrosine phosphatase (SHP-2) to form a CagA-SHP-2 complex. This complex depends on the similarity of sequence between EPIYA motif and Src homology 2 domain (SH2 domain) of CagA. The generation of growth factors is an essential role of CagA in protecting and healing gastric mucosa for the survival of H. pylori. On the other hand, the activation of IL-8 by CagA induces neutrophils generating inflammation and free radicals. Indeed, free radicals are well known carcinogen to induce DNA damage. In addition, the transduction of mitogen-activation signal by CagA is one of the interesting features to understand how to cause cancer. The relationship between cancer and inflammation with CagA was mainly discussed in this review.

• 생약학회지
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• 제35권3호통권138호
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• pp.250-254
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• 2004

Helicobacter pylori (H. pyroli) infection it associated with type B gastritis, peptic uler disease, and gastric cancer. The vacuolation of cells induced by H. pylori is thought to be essential for the initiation and maintenance of gastric infection. The roles of H. pylori cytotoxin, urease, and ammonia in the vacuolation of HeLa cells were determined. H. pylori toxin induced vacuolation of HeLa cells. Korean and Japanese radishes significantly prevented the vacuolation of HeLa cells induced by H. pylori toxin. The urease activity in vacuolated cells was also decreased with Korean and Japanese radishes. H. Pylori toxin-induced vacuolation was inhibited by vacuolar type ATPase inhibitors (bafilomycin and N-ethylmaleimide). However, further investigation is required to determine the mechanisms of radish for the inhibition of vacuole formation of eukaryotic cells in response to the H. pylori toxin.

• Food Science and Biotechnology
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• 제17권2호
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• pp.219-227
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• 2008

Bacillus thuringiensis was isolated as a pathogen of the sotto disease of silkmoth larvae about a hundred years ago. Since then, this bacterium has attracted attentions of not only insect pathologists but also many other scientists who are interested in its strong and specific insecticidal activity. This has led to the recent worldwide development of B. thuringiensis-based microbial insecticides and insect-resistant transgenic plants, as well as a landmark discovery of par asp orin, a cancer cell-specific cytotoxin produced by B. thuringiensis. In this review, we describe examination of interaction between inclusion proteins of B. thuringiensis and brush border membrane of insects using a surface plasmon resonance-based biosensor, identification and characterization of parasporin-4, the latest parasporin produced by the B. thuringiensis A1470 strain, and an effective method for preparing the parasporin-4 from inclusion bodies expressed in the recombinant Escherichia coli cells.

• 환경위생공학
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• 제6권1호
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• pp.31-46
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• 1991

Aeromonas hydrophila which bacause various diseases in human also infects fresh water fish, severly damaging the fishing industries. To prevent disease in humans and reduce damaging on the fishing industries, We have examined several characteristics of Aeromonas hydrophila and obtained the following results. All of the strains gave a posive voges-proskauer, methyl-red, salicin and esculin reaction. Seventeen(94.4%) A. hydrophila strains presented the phenotype SP-PAB- in autoagglut-ination test, but only strain AH 997 showed $SP^{+}PAB^{+}$. in autoagglut ination test, but only strain AH 997 $SP^{+}PAB^{+}$ All of the strains took up the censored to various degrees. Three of 18 strains showed positive reaction in crystal violet binding test. Hemolytic activity ranged from titers of 0 to 1/256. Seven of the 17(38.8%) A. hydrophila strains were positive in sucking mouse assay. Cytotoxin activity on vero and RK cells was displayed various titers.(1/2-1/1024)

• 한국수의병리학회:학술대회논문집
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• 한국수의병리학회 2005년도 Proceedings of The 2nd Asian Society of Veterinary Pathology Symposium(Vol.2) and 2005 Annual Meeting of The Korean Society of Veterinary Pathology(Vol.9)
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• pp.89-90
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• 2005

• 혜화의학회지
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• 제9권1호
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• pp.379-386
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• 2000

1. There two parts of alcohol's metabolic system the first one is alcoholdehydrogenase(ADH), and second is microsomal ethanol oxidizing system(MEOS). 2. Alcoholic cirrhosis(fibrosis) leads from cytotoxin, malnutrition, and immunue reaction. 3. In the Oriental medical point of view alcohol has strong heat and toxin, which can cause judal, ju-ka, ju-beack, ju-juck, and ko-chang in other words these means that it can cause hepatasis, fatty liver, fibrosis, and liver cirrhosis. 4. About the Liver cirrhosis(fibrosis) pathological system, in the oriental medical point of view, it effects the liver, kidney and spleen which causes Uy-heulGin-guk(瘀血 積), seup-yeul ne-oun(濕熱內蘊), and in the long term it can cause kansinyumhu(肝腎陰虛), kanbeyumhu(肝脾陰虛). Because of the expand of alcohol liver disease, in the future there must be more studies about these disease in Oriental medicine point of view.

• Pediatric Infection and Vaccine
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• 제25권1호
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• pp.50-53
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• 2018

Staphylococcus aureus is a well-recognized human pathogen that causes a wide range of infections as a result of its extensive virulence factors. One of these factors is Panton-Valentine leukocidin (PVL), a potent pore-forming cytotoxin that has been linked to invasive S. aureus infections. PVL is one of the important virulence factors for S. aureus and has been largely recognized as one of the markers for community-acquired methicillin-resistant S. aureus. However, the presence of PVL in methicillin-susceptible S. aureus infections is not widely reported in the literature. Thrombotic sequelae of S. aureus infections associated with PVL expression are uncommon in children. We hereby report two children with thrombotic complications associated with PVL-producing methicillin-susceptible S. aureus. Both patients responded well to antibiotic and anticoagulant therapies, and survived without any long-term sequelae.

• 대한임상검사과학회지
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• 제50권3호
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• pp.275-283
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• 2018

Helicobacter pylori는 만성 위염, 위궤양 또는 위 선암을 비롯한 다양한 위장병의 원인균으로 알려져 있으며, 이 세균이 분비하는 cytotoxin-associated protein A (CagA), vacuolating cytotoxic protein A (VacA)와 같은 병원성 인자가 그 원인으로 알려져 있다. 본 연구에서는 zerumbone이 CagA, VacA를 비롯한 다양한 H. pylori의 병원성 인자들의 단백 발현양 변화에 정성적, 정량적으로 어떠한 영향을 미치는지 분석하였다. H. pylori 60190 (VacA 양성 / CagA 양성; Eastern type) 표준균주를 대상으로 하여 약 200개의 유의미한 단백을 선별한 후, 그 중에서 임상적으로 의의가 큰 13개 단백 분자에 대한 프로테옴 분석을 수행하였다. 이차원 전기 영동법(2 dimensional electrophoresis, 2-DE) 수행 후, 단백질 스팟의 정량적 측정에는 ImageMasterTM 2-DE Platinum 소프트웨어를 사용하였고, 단백 동정에는 matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-TOF-MS)와 liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS)를 사용하였다. 동정이 완료된 전체 단백 중에서 유의미한 변화를 보인 단백을 집중적으로 분석한 뒤에 필요에 따라 reverse transcription -polymerase chanin reaction을 수행하여 결과를 추가 검증하였다. 본 연구에서는 zerumbone이 보유한 새로운 약리학적 활성 기전을 스크리닝함으로써 향후 zerumbone이 H. pylori 감염증 치료제로서 어떠한 의미를 지니는지 규명하고자 하였다.

• 한국미생물·생명공학회지
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• 제27권5호
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• pp.419-425
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• 1999

Prophylactic effects of Bifidobacterium longum HY8001, Korean isolate, against Escherichia coli O157:H7 and Salmonella typhimurium DT104 enteric infection were examined at four groups of specific pathogen free(SPF)-ICR mouse for each pathogen. B. longum HY8001+B. typhimurium DT104+B. longum HY8001(BL+ST+BL) group and B. longum HY8001+E. coli O157:H7+B. longum HY8001(BL+E+BL) group were fed with B. longum HY8001 before and after E. coli O157:H7 or s. typhimurium DT104 challenge, while B. longum HY8001+S. typhimurium DT104(BL+ST) and B. longum HY8001+e. coli O157:H7(BL+E) groups were fed with B. longum HY8001 only before E. coli O157:H7 or S. typhimurium DT104 challenge. E. coli O157:H7(E) and S. typhimurium DT104(ST) groups were challenged with each pathogen without B. longum HY8001 administration and control groups were administered with phosphate buffered solution(PBS). After the oral administration with B. longum HY8001(109cfu), th emice were challenged with E. coli O157:H7(2$\times$1010cfu) or S. typhimurium DT104(108cfu) and the mortality rate and the fecal shedding of challenged pathogen were also examined define the reactivity of the B. longum HY8001. Production of toxin neutralizing substance(s) of B. longum HY8001 was determined by cell cytotoxicity assay using Vero cells. Fecal shedding of th eS. typhimurium DT104 was significantly decreased in BL+ST+BL group fed with B. longum HY8--1 before and after challenge(p<0.05), while the fecal shedding s of S. typhimurium DT104 in BL+ST and St groups remained more than 106cfu. the protective effect of the B. longum HY8001 against E. coli O157:H7 was significantly high only in BL+E+BL group fed with b. longum Hy8001 before and after E. coli O157:H7 challenge from the result of fecal E. coli O157:H7 isolation rate, mortality rate, and intestinal contents culture to detect E. coli O157:H7. the mortality rate of the BL+e and E groups. The cytopathic effect (CPE) of the Vero cytotoxin (Shiga like toxin I & II) in Vero cell was neutralized in B. longum HY8001 culture supernatant added wells which indicate the presence of soluble Vero cytotxin neutralizing substance(s) in B. longum HY8001 culture suprnatant.

• Asian Pacific Journal of Cancer Prevention
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• 제16권13호
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• pp.5199-5203
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• 2015

Background: Helicobacter pylori (H.pylori) is associated with chronic gastritis, peptic ulcers, gastric adenocarcinomas and mucosa associated tissue lymphomas. Cytotoxin associated gene A (CagA) is one of the virulence factors of H.pylori. It is hypothesized that reactive oxygen species (ROS) play roles in H.pylori associated disease especially in development of gastric adenocarcinoma. Individuals infected with H.pylori bearing CagA produce more ROS than others. 8-hydroxydeoxyguanosine (8OHdG) is an in vitro marker of DNA damage and oxidative stress. The aim of this study was to investigate the relationship between 8OHdG level, H.pylori infection and CagA and alterations of serum 8OHdG level after H.pylori eradication. Materials and Methods: Patients admitted with dyspeptic complaints and upper gastrointestinal endoscopy were assessed. H.pylori was determined from histopathology of specimens. Serum 8OHdG levels of three groups (H.pylori negative, H. pylori positive CagA negative and H.pylori positive CagA positive) were compared. Patients with H.pylori infection received eradication therapy. Serum 8OHdG levels pretreatment and posttreatment were also compared. Results: In total, 129 patients (M/F, 57/72) were enrolled in the study. Serum 8OHdG level of H.pylori negative, H. pylori positive CagA negative and H.pylori positive CagA positive groups were significantly different ($5.77{\pm}1.35ng/ml$, $5.43{\pm}1.14ng/ml$ and $7.57{\pm}1.25ng/ml$ respectively, p=0.05). Furthermore, eradication therapy reduced serum 8OHdG level ($6.10{\pm}1.54ng/ml$ vs $5.55{\pm}1.23ng/ml$, p=0.05). Conclusions: Individuals infected with H.pylori bearing CagA strains have the highest serum 8OHdG level and eradication therapy decreases the serum 8OHdG level. To the best of our knowledge this is the first study that evaluated the effect of CagA virulence factor on serum 8OHdG level and the effect of eradication therapy on serum 8OHdG levels together. Eradication of CagA bearing H.pylori may prevent gastric adenocarcinoma by decreasing ROS. 8OHdG level may thus be a good marker for prevention from gastric adenocarcinoma.