• Pediatric Infection and Vaccine
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• 제16권2호
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• pp.162-166
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• 2009

목 적: 소아에서 요로 감염은 가장 흔한 세균 질환 중 하나로 합병증으로 신손상이 초래될 수 있다. 신손상의 위험 인자로는 더 어린 나이에 발병하거나, 요로계의 선천 기형이 동반되는 경우, 치료의 시작이 늦어진 경우, 비 E. coli에 의한 경우 등이다. 따라서 본 연구에서는 영아에서 E. coli UTI의 특징적인 임상 및 검사실 소견을 non-E. coli UTI과 비교해보았다. 방 법: 1998년 1월부터 2007년 12월까지 가톨릭대학교 성빈센트병원 소아청소년과에 요로 감염으로 진단된 12개월 미만의 환자를 대상으로 하였다. 모든 환자들을 E. coli UTI군과 non-E. coli UTI 군으로 나누어 의무기록 및 검사 소견을 후향적으로 조사하였다. 결 과: 연구군의 포함 기준에 합당한 환자는 총 324명이었으며, 이중 273명(84.3%)은 E. coli에 의한 요로 감염, 나머지 51명(15.7%)은 다른 균에 의한 감염이었다. E. coli UTI 군은 non-E. coli UTI 군에 비해 발병 연령이 더 어리고(3.59 vs 4.47개월, P =0.008), 입원 후 농뇨의 소실 기간이 더 길었고 (3.96 vs 3.06일, P =0.010), 진단 당시 말초 혈액 검사에서 백혈구 수가 더 많았으나(13.89 vs $12.13{\times}10^3/mm^3, P =0.043), III 등급 이상의 고등급 방광 요관 역류의 동반 빈도는 낮았다(P =0.005). 그러나 입원 후 해열 기간 및 항균제 치료의 반응에는 차이가 없었다. 결 론: 요로감염에서 균주에 따른 재발률 및 신 손상 등 장기 예후에 대한 추가적인 연구를 시행하여 영상 검사 및 치료 방침을 차별화 하여야 할 것으로 사료된다.

• Journal of Microbiology and Biotechnology
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• 제24권9호
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• pp.1232-1237
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• 2014

Lycopene, which is a well-known red carotenoid pigment, has been drawing scientific interest because of its potential biological functions. The current study reports that lycopene acts as a bactericidal agent by inducing reactive oxygen species (ROS)-mediated DNA damage in Escherichia coli. Lycopene treatment elevated the level of ROS-in particular, hydroxyl radicals ($^*OH$)-which can damage DNA in E. coli. Lycopene-induced DNA damage in bacteria was confirmed and we also observed cell filamentation caused by cell division arrest, an indirect marker of the DNA damage repair system, in lycopene-treated E. coli. Increased RecA expression was observed, indicating activation of the DNA repair system (SOS response). To summarize, lycopene exerts its antibacterial effects by inducing $^*OH$-mediated DNA damage that cannot be ameliorated by the SOS response. Lycopene may be a clinically useful adjuvant for current antimicrobial therapies.

• Clinical and Experimental Pediatrics
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• 제46권8호
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• pp.777-783
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• 2003

목 적 : E. coli 패혈성 폐가 유도된 신생자돈에서 Nitric oxide(NO) 가스 흡입요법이 혈역학, 가스교환 및 폐 염증 소견에 미치는 영향을 알아보고자 본 연구를 실시하였다. 방 법 : 23마리의 신생자돈에서 도관 삽입과 기도 삽관을 시행하여 기계적 가스 인공환기를 시키면서 CON군(n=6)은 생리적 식염수 5 mL, PCON(n=9) 및 PNO(n=8) 군은 Escherichia coli strain $69{\times}10^9cfu$(10 mL)를 투여한 후 time-cycled pressure-limited 인공환기기로 PIP 30 $cmH_2O$, 호흡수 분당 30회, $FiO_2$ 1.0, PEEP 4 $cmH_2O$의 설정에서 6시간 동안 유지하였다. PNO군에서는 NO 10 ppm을 E. coli 투여 후부터 실험 종료 시까지 기도 내로 투여하였다. 모든 신생자돈에서 가스교환, 혈역학, 폐기능 지수들을 1시간 간격으로 측정하였고 실험 종료후 폐 조직을 얻어 염증반응 정도 지표인 myeloperoxidase 활성을 측정하였다. 결 과 : E. coli가 기도 내로 투여된 PCON 및 PNO군 모두에서 실험 종료시 E. coli 패혈증이 발생하였다. PCON군에서는 시간에 따라 진행되는 폐동맥 고혈압, 저산소혈증, 고탄산혈증, 및 폐 내 단락과 폐 내 사강의 비율의 증가를 보였고 대조군에서는 실험 종료시까지 의미 있는 변화를 보이지 않았다. NO가 투여된 PNO군에서 폐동맥 고혈압이 감소되지 않았으나 폐 내 단락의 의미 있는 개선과 폐 내 사강 비율 증가의 일부 감소에 기인한 저산소혈증 진행의 완화가 관찰되었다. 폐 염증정도의 지표인 폐조직의 myeloperoxidase 활성도는 PCON군에서 CON군에 비해 의미 있게 증가되었으며 이는 PNO군에서 의미 있게 완화되었다. 결 론 : E. coli 패혈성 폐가 유도된 신생자돈에서 NO 가스 흡입요법은 폐 내 단락 개선을 통해 산소화를 향상시켰으며 또한 폐 염증 소견을 완화시켰다.

• 한국미생물·생명공학회지
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• 제19권5호
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• pp.491-496
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• 1991

Aminoglycoside-3'-phosphotransferase(APH(3'))를 생산하는 균주인 E.coli ATCC 21990을 산업적으로 이용하기 위해서 자외선 조사 및 NTG를 처리하고 고농도의 kanamycin B에 내성을 갖는 변이주인 E.coli M1과 M2를 선별하였다. E.coli M1은 단위 균체당 효소 생산성은 높으나 생육속도가 낮아 실용적이질 못했고 주 질소원인 yeast extract를 사용했을때 E.coli M1보다 E.coli M2가 생육속도가 훨씬 빨랐으며 약 2배의 APH(3')을 얻을 수 있었고 산소 가스를 사용하였을 경우는 약 2.5배의 APH(3')을 얻었다.

• Journal of Animal Science and Technology
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• 제63권3호
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• pp.501-509
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• 2021

The aim of this was evaluate the efficacy of lysozyme on growth performance, nutrient digestibility, excreta microflora population, and blood profiles of weanling pigs under Escherichia coli (E. coli) challenge. A total of 30 piglets weaned at 25 days, 7.46 kg body weight, were assigned to three dietary treatments, composed of five replications, two piglets per replication, for 7 days. The dietary treatment groups were negative control (NC; without antibiotics and lysozyme), positive control (PC; NC + antibiotics), lysozyme (NC + 0.1% lysozyme). All piglets were challenged orally with 6 ml suspension, containing E. coli K88 (2 × 10⁹ CFU/mL). Dietary supplementation with lysozyme and PC resulted in no significant differences in average daily gain and gain to feed efficiency. Weanling pigs fed with E. coli challenge with lysozyme and PC treatments had significantly enhanced nutrient retentions of dry matter and energy (p < 0.05); however, there was a tendency to increase nitrogen digestibility. Furthermore, dietary inclusion of lysozyme and antibiotics treatment groups had a beneficial effect on excreta, ileal, and cecal of the fecal microbial population as decreased E. coli (p < 0.05) counts, without effects on lactobacillus counts. A significant effect were observed on a white blood cells, epinephrine and cortisol concentrations were reduced in piglets fed diets containing E. coli challenge with lysozyme and antibiotics supplementation comparison with the NC group. Therefore, the present data indicate that lysozyme in diet could ameliorate the experimental stress response induced by E. coli in piglets by decreasing intestinal E. coli, white blood cells and stress hormones and improving nutrient digestibility.

• 대한수의학회지
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• 제27권2호
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• pp.259-267
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• 1987

Enterotoxigenic E. coli (ETEC) cause an acute diarrhea (white scour) in both animals and humans. The disease process initially involves the adherence and colonization of the mucosal surface of the small intestine, followed by the elaboration of a heat-labile enterotoxin (LT) and/or heat-stable enterotoxin (ST). Intestinal adherence or colonization by ETEC is generally mediated by a specific surface-associated pilus (fimbrial) antigen that endows the bacteria with the capacity to adhere to epitherial cell surface. Fourteen monoclonal antibodies (MAbs) directed against pili antigens of ETEC were obtained by cell fusion/hybridoma technique. They were characterized by indirect immunofluorescence assay (IFA), and divided into four groups: specific to K99 antigen (group 1), cross-reactive with K99 and F41 antigens (group 2), specific to K88 antigen (group 3) and specific to 987P and K88 antigens (group 4), respectively. These MAbs demonstrated the distinct pili (K) antigens on the surface of ETEC by IFA, and could be utilized as diagnostic reagent for the identification of ETEC. When eighty-seven field isolates of E. coli from piglet with diarrhea were tested by group 3 MAb, fourty-two strains (48.3%) has K88 pilus antigen suggesting that this is one of the major pilus antigen of ETEC present in fifeld.

• Journal of Microbiology and Biotechnology
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• 제21권8호
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• pp.854-857
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• 2011

POMT7, which is an O-methyltransferase from poplar, transfers a methyl group to several flavonoids that contain a 7-hydroxyl group. POMT7 has been shown to have a higher affinity toward quercetin, and the reaction product rhamnetin has been shown to inhibit the formation of beta-amyloid. Thus, rhamnetin holds great promise for use in therapeutic applications; however, methods for mass production of this compound are not currently available. In this study, quercetin was biotransformed into rhamnetin using Escherichia coli expressing POMT7, with the goal of developing an approach for mass production of rhamnetin. In order to maximize the production of rhamnetin, POMT7 was subcloned into four different E. coli expression vectors, each of which was maintained in E. coli with a different copy number, and the best expression vector was selected. In addition, the S-adenosylmethionine biosynthesis pathway was engineered for optimal cofactor production. Through the combination of optimized POMT7 expression and cofactor production, the production of rhamnetin was increased up to 111 mg/l, which is approximately 2-fold higher compared with the E. coli strain containing only POMT7.

• KSBB Journal
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• 제29권6호
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• pp.443-447
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• 2014

Biosynthesis of lactate-containing polyhydroxyalkanoates (PHAs) was examined in recombinant Escherichia coli W strain from sucrose. The Pseudomonas sp. MBEL 6-19 phaC1437 gene and the Clostridium propionicum pct540 gene, which encode engineered Pseudomonas sp. MBEL 6-19 PHA synthase 1 ($PhaC1_{Ps6-19}$) and engineered C. propionicum propionyl-CoA transferase ($Pct_{Cp}$), respectively, were expressed in E. coli W to construct key metabolic pathway to produce poly(3-hydroxybutyrate-co-lactate) [P(3HB-co-LA)]. The recombinant E. coli W expressing the phaC1437 gene and the pct540 gene could synthesize P(3HB-co-13mol%LA) up to the polymer content of 31.3 wt% when it was cultured in chemically defined MR medium containing 20 g/L of sucrose and 2 g/L of sodium 3-hydroxybutyrate. When Ralstonia eutropha phaAB genes were additionally expressed to provide 3-hydroxybutyrate-CoA (3HB-CoA) from sucrose, P(3HB-co-16mol%LA) could be synthesized from sucrose as a sole carbon source without supplement of sodium 3-hydroxybutyrate in culture medium, but the PHA content was decreased to 12.2 wt%. The molecular weight of P(3HB-co-16 mol%LA) synthesized in E. coli W using sucrose as carbon source were $1.53{\times}10^4$ ($M_n$) and $2.78{\times}10^4$ ($M_w$), respectively, which are not different from those that have previously been reported by other recombinant E. coli strains. Engineered E. coli strains developed in this study should be useful for the production of lactate-containing PHAs from sucrose, one of the most abundant and least expensive carbon sources.

• Asian-Australasian Journal of Animal Sciences
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• 제33권3호
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• pp.456-464
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• 2020

Objective: The aim of this study is to investigate the effect of oral spray with probiotics on the intestinal development and microflora colonization of hatched ducklings. Methods: In Exp. 1, an one-way factorial design was used to study the antibacterial activity of the probiotics and metabolites on Escherichia coli (E. coli) without antimicrobial resistance. There were four experimental groups including saline as control and Lactobacillus, Bacillus subtilis, combined Lactobacillus and Bacillus subtilis groups. In Exp. 2, 64-day-old ducklings were allotted to 2 treatments with 4 replicated pens. Birds in the control group were fed a basal diet supplemented with Lactobacillus fermentation in the feed whereas birds in the oral spray group were fed the basal diet and administrated Lactobacillus fermentation by oral spray way during the first week. Results: In Exp. 1, the antibacterial activities of probiotics and metabolites on E. coli were determined by the diameter of inhibition zone in order: Lactobacillus>combined Lactobacillus and Bacillus subtilis>Bacillus subtilis. Additionally, compared to E. coli without resistance, E. coli with resistance showed a smaller diameter of inhibition zones. In Exp. 2, compared to control feeding group, oral spray group increased (p<0.05) the final body weight at d 21 and average daily gain for d 1-21 and the absolute weight of the jejunum, ileum and total intestine tract as well as cecum Lactobacillus amount at d 21. Conclusion: Lactobacillus exhibited a lower antibacterial activity on E. coli with resistance than E. coli without resistance. Oral spray with Lactobacillus fermentation during the first week of could improve the intestinal development, morphological structure, and microbial balance to promote growth performance of ducklings from hatch to 21 d of age.

• International Journal of Oral Biology
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• 제37권3호
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• pp.85-90
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• 2012

Periodontal disease induces an increased incidence of tooth loss, particularly in cases with an associated loss of alveolar bone and periodontal ligaments. In this study, alveolar bone loss was detected by micro-computed tomography (CT) following exposure to E. coli lipopolysaccharide (LPS) in a streptozotocin (STZ)-induced diabetic mouse model. A 10 mg/ml dosage of E. coli LPS was applied between the first, second and third molars of the mice three times a week for 10 weeks. The loss of periodontal ligaments and alveolar processes was then evaluated by micro-CT using two and three dimensional microstructure morphometric parameters. In the diabetic mice, E. coli LPS induced the destruction of periodontal ligaments and loss of alveolar process spaces. The distances between periodontal ligaments were significantly widened in the STZ-LPS group compared with the untreated STZ group. The 10 mg/ml exposure to E. coli LPS in the STZ mice also resulted in a significant decrease in the alveolar bone volume fraction. The results of our study suggest that alveolar bone loss can be readily detected by volumetric micro-CT analysis as an increase in the distance between periodontal ligaments and in the alveolar process length.