• Journal of Microbiology and Biotechnology
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• v.31 no.4
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• pp.621-629
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• 2021

Shigella flexneri is a facultative intracellular pathogen that causes bacillary dysentery in humans. Infection with S. flexneri can result in more than a million deaths yearly and most of the victims are children in developing countries. Therefore, identifying novel and unique drug targets against this pathogen is instrumental to overcome the problem of drug resistance to the antibiotics given to patients as the current therapy. In this study, a comparative analysis of the metabolic pathways of the host and pathogen was performed to identify this pathogen's essential enzymes for the survival and propose potential drug targets. First, we extracted the metabolic pathways of the host, Homo sapiens, and pathogen, S. flexneri, from the KEGG database. Next, we manually compared the pathways to categorize those that were exclusive to the pathogen. Further, all enzymes for the 26 unique pathways were extracted and submitted to the Geptop tool to identify essential enzymes for further screening in determining the feasibility of the therapeutic targets that were predicted and analyzed using PPI network analysis, subcellular localization, druggability testing, gene ontology and epitope mapping. Using these various criteria, we narrowed it down to prioritize 5 novel drug targets against S. flexneri and one vaccine drug targets against all strains of Shigella. Hence, we suggest the identified enzymes as the best putative drug targets for the effective treatment of S. flexneri.

• Journal of Microbiology and Biotechnology
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• v.29 no.4
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• pp.518-526
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• 2019

Pueraria montana var. lobata is a bioactive substance with various beneficial health effects and has long been extensively used as a traditional medication for the treatment of fever, acute dysentery, diabetes, and cardiovascular diseases in Northeast Asian countries. The purpose of this study was to evaluate the cytoprotective activity of Pueraria montana var. lobata ethanol extract (PLE) for ultraviolet B (UVB)-induced oxidative stress in human dermal fibroblasts (HDF). It was hypothesized that PLE treatment ($25-100{\mu}g/ml$) would reduce intracellular reactive oxygen species (ROS) levels as well as increase collagen production in UVB-irradiated HDF. The results confirmed this theory, with collagen production increasing in the PLE treatment group in a dose-dependent manner. In addition, regulators of cellular ROS accumulation, including HO-1 and NOQ-1, were activated by Nrf2, which was mediated by PLE. Hence, intracellular levels of ROS were also reduced in the PLE treatment group in a dose-dependent manner. In conclusion, PLE increases collagen production and maintains hyaluronic acid (HA) levels in human dermal fibroblasts exposed to UVB-irradiation, thereby inhibiting photoaging.

• Microbiology and Biotechnology Letters
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• v.51 no.2
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• pp.217-221
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• 2023

Aeromonas spp., are Gram-negative rods that can cause infections in healthy and immunocompromised hosts. The clinical presentation of gastroenteritis varies from mild diarrhoea to shigella-like dysentery to severe cholera-like watery diarrhoea. Here, we report a case of acute hemorrhagic gastroenteritis in a newborn infant by Aeromonas caviae and its draft genome sequence. It is important to reduce the chance of incorrect isolate identification, which could lead to the exclusion of pathogenic Aeromonas spp., from routine laboratory identification in cases of diarrheal diseases. The genome sequence of A. caviae SVJ23 represents a significant step forward in understanding the diversity and pathogenesis, virulence, and antimicrobial resistance profile.

• Preventive Nutrition and Food Science
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• v.14 no.4
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• pp.269-276
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• 2009

Overproduction of reactive oxygen species (ROS), including nitric oxide (NO), could be associated with the pathogenesis of various diseases such as cancer and chronic inflammation. Inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) are known to play key roles in the development of these diseases. Cedrela sinensis leaves have been used in Asian countries as a traditional remedy for enteritis, dysentery and itching. In the present study, we investigated the anti-inflammatory effects of Cedrela sinensis leaves in lipopolysaccharide (LPS)- stimulated RAW 264.7 macrophages. Powder of C. sinensis leaves was extracted with 95% ethanol and fractionated with a series of organic solvents including n-hexane, dichloromethane, ethyl acetate, n-butanol, and water. The dichloromethane (DCM) fraction strongly inhibited NO production possibly by down-regulating iNOS and COX-2 expression, as determined by Western blotting. Hydrogen peroxide-induced generation of reactive oxygen species (ROS) was also effectively inhibited by the DCM fraction from C. sinensis leaves. In addition, C. sinensis inhibited LPS-mediated p65 activation via the prevention of IκB-$\alpha$ phosphorylation. Furthermore, mitogen-activated protein kinases (MAPKs) such as ERK 1/2 and p38 were found to affect the expression of iNOS and COX-2 in the cells. Taken together, our data suggest that leaves of C. sinensis could be used as a potential source for anti-inflammatory agents.

• Pediatric Infection and Vaccine
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• v.14 no.1
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• pp.111-115
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• 2007

Entamoeba histolytica (E. histolytica) is a worldwide protozoan parasite causing a wide rage of intestinal disease in human, including asymptomatic cyst carriage, acute diarrhea, fulminant dysentery, and chronic nondysenteric colitis. Extraintestinal amebiasis such as hepatic abscess also occurs. Spread of the infection occurs due to consumption of food and water that is contaminated with the cyst. Amebiasis is rarely reported in the newborn period. We report a case of a 6-day-old female newborn with watery diarrhea that progressed to bloody mucoid diarrhea with persistent fever. The fresh stool microscopic examination disclosed E. histolytica trophozoites. She was born of spontaneous vaginal delivery at 41 weeks of gestation after premature rupture of membrane. She was given breast-feeding after birth, then entered postpartum care center. Her mother's stool microscopic examination showed negative result. Infection might have occurred from giving sweetened water following birth or contamination of the baby's bottles at the postpartum care center. She was treated with oral metronidazole for 24 days.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.442-446
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• 2006

Cedrela sinensis is a broadleaf tree that is widely cultivated in Korea and China. It was used for treating enteritis, dysentery, and skin itch in oriental medicine. In this study, three major flavonoids, kaempferol-3-O-rhamnoside (1), quercetin-3-O-rhamnoside (2), and quercetin-3-O-glucoside (3), were isolated from the leaf of Cedrela sinensis. The biological activities of these compounds were tested by inhibitory activity of matrix metalloproteinases-2 (Type IV collagenase) method together with a cytotoxicity and a apoptosis test against human cancer cell lines.

• Journal of Physiology & Pathology in Korean Medicine
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• v.30 no.4
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• pp.266-273
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• 2016

Ohmae-hwan has been used to treat the symptoms of loose stools mixed with blood accompanied by abdominal pain due to heat dysentery in Korean medicine. However, its mechanism of action on inflammatory disease using macrophages was not known. The author was to find out about the influence of Ohmae-hwan water extract on expressions of NO, cytokine IL-6 and TNF-α in LPS-stimulated RAW 264.7 cell, on expressions of mRNA of iNOS, IL-6 and COX-2 and on suppression of expressions of protein of iNOS and COX-2, and was to find out about the mechanism. As a result of the study, it was found that Ohmae-hwan suppressed generation of NO activated by LPS depending on its concentrations, suppressed expressions of cytokine IL-6, and TNF-α and suppressed expressions of mRNA of iNOS, IL-6, and COX-2 and suppressed expressions of protein of iNOS, COX-2. Considering the above results, it can be known that Ohmae-hwan water extract has anti-inflammatory effect against inflammatory response mediated by macrophages by suppressing generation of NO, TNF-α, and IL-6 and expressions of iNOS, COX-2 as it acts on macrophages.

• Parasites, Hosts and Diseases
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• v.52 no.5
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• pp.459-469
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• 2014

Entamoeba histolytica is a tissue-invasive protozoan parasite causing dysentery in humans. During infection of colonic tissues, amoebic trophozoites are able to kill host cells via apoptosis or necrosis, both of which trigger IL-8-mediated acute inflammatory responses. However, the signaling pathways involved in host cell death induced by E. histolytica have not yet been fully defined. In this study, we examined whether calpain plays a role in the cleavage of pro-survival transcription factors during cell death of colonic epithelial cells, induced by live E. histolytica trophozoites. Incubation with amoebic trophozoites induced activation of m-calpain in a time- and dose-dependent manner. Moreover, incubation with amoebae resulted in marked degradation of STAT proteins (STAT3 and STAT5) and NF-${\kappa}B$ (p65) in Caco-2 cells. However, $I{\kappa}B$, an inhibitor of NF-${\kappa}B$, was not cleaved in Caco-2 cells following adherence of E. histolytica. Entamoeba-induced cleavage of STAT proteins and NF-${\kappa}B$ was partially inhibited by pretreatment of cells with a cell-permeable calpain inhibitor, calpeptin. In contrast, E. histolytica did not induce cleavage of caspase-3 in Caco-2 cells. Furthermore, pretreatment of Caco-2 cells with a calpain inhibitor, calpeptin (but not the pan-caspase inhibitor, z-VAD-fmk) or m-calpain siRNA partially reduced Entamoeba-induced DNA fragmentation in Caco-2 cells. These results suggest that calpain plays an important role in E. histolytica-induced degradation of NF-${\kappa}B$ and STATs in colonic epithelial cells, which ultimately accelerates cell death.

• Journal of the korean veterinary medical association
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• v.32 no.8
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• pp.535-539
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• 1996

국제양돈수의학회(International Pig Veterinary Society ; I.P.V.S) 제14차 총회 및 학술대회가 1996년 7월 7일부터 11일까지 이태리 중북부의 대학도시 볼로냐(Bologna, Italy)에서 개최되었다. I.P.V.S.는 1969년에 영국의 캠브리지 (Cambridge, United Kingdom)에서 창립된 이래 1996년 현재 53개 회원국 1,700 여명의 회원을 확보하고 있으며, 세계 각국의 양돈과 수의학에 관심을 가지고 있는 학자, 생산자 그리고 관련업계 인사들의 학술$\cdot$기술 정보교류와 협력을 목적으로 매 2년마다 세계 주요도시를 순회 하면서 개최되고 있다. 앞으로 2년후(1998년도)에는 I.P.V.S.의 탄생국인 영국의 버밍햄(Birmingham, United Kingdom)에서 제 15차 총회 및 학술대회를 개최할 예정이며 2000년대에는 시드니 올림픽과 때를 맞추어 호주의 멜보른(Melboume, Australia)에서 제16차 총회를 개최하기로 결정되어 있다. 금년(1996년도) I.P.V.S 총회에는 우리나라에서 30개 기관/업체로부터 50여명이 참여한 바 있으며 총 27편 (구두 9편, 포스터 18편)의 학술논문을 발표하는 등 눈부신 활약을 보인 바 있다. 금년도 I.P.V.S. 총회의 특징은 돼지의 전염성 질병중 근래에 우리나라에서도 문제시 되고 있는 '돼지 생식기 호흡기 중후군 (Porcine Reproductive and Respiratory Syndrome ; PRRS)'이 세계적인 관심의 대상이었으며, 이태리 양돈병리축산학회 (Societa Italiana di Patologia ed Allevamento dei Suini ; S.I.P.A.S) 주관으로 '돼지 적리 (Swine Dysentery)'에 관한 Satellite Symposium이 개최되었다는 점이다. WTO 이래 어려워지고만 있는 우리나라 축산업 분야중 그래도 비젼이 보이는 양돈산업과 관련하여, I.P.V.S.를 통하여 우리나라 수의업무의 세계화의 길을 찾아보고자, 1 국제양돈수의학회(I.P.V.S)의 역사 (양돈과 수의업무 전문가의 새로운 만남의 장), 2 I.P.V.S.에의 참여(제13차 방콕대회), 3 한국 수의사의 활약(제14차 볼로냐대회), 4 세계화의 길(제15차 버밍햄대회, 제16차 멜보른대회), 5 국내양돈의 문제와 우리가 해야할 일(수의업무 세계화의 길을 찾자)등의 순으로 적어보고자 한다.

• Korean Journal of Pharmacognosy
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• v.38 no.3 s.150
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• pp.263-269
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• 2007

Nelumbo nucifera (Nymphaeaceae) has been widely used in a traditional oriental medicine to treat bleeding, fever, diarrhea, hemorrhoid, sunstroke, dysentery and dizziness. The leaves of this plant were refluxed with methanol, and then fractionated with organic solvents to screen the antioxidant activity using DPPH radical. Ethyl acetate and n-butanol fractions showed good DPPH radical scavenging effects and were carried out column chromatographies to isolate nine compounds. Their chemical structures were characterized as p-hydroxybenzoic acid (1), uracil (2), luteolin (3), quercetin $3-O-{\beta}-D-glucopyranoside$ (4), $rhamnetin 3-O-{\beta}-D-glucopyranoside$ (5), $isorhamnetin 3-O-{\beta}-D-glucopyranoside$ (6), $quercetin 3-O-{\beta}-D-glucuropyranoside$ (7), $quercetin 3-O-{\beta}β-D-xylofuranosyl(1{\rightarrow}2)-{\beta}-D-galactopyranoside$ (8), and adenine (9) by comparison NMR spectral data and with those in references. Compounds 1, 2, 5 and 9 were firstly isolated from this plant. Compounds 1, 3 and 4 showed potent DPPH radical scavenging activity. Especially, compound 3, luteolin showed the higher effect than ascorbic acid used as a positive control.