• 자원환경지질
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• 제42권5호
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• pp.471-477
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• 2009

물속에 우라닐이온(${UO_2}^{2+}$) 형태로 존재하는 산화우라늄을 철환원세균인 스와넬라균(Shewanella p.)을 이용하여 제거하는 실험을 수행하였다. 용액상의 우라늄 초기농도는 $50{\mu}M$ 이었으며 미생물과의 반응에 의해 점차 그 농도가 감소하였고, 약 2주 후에 거의 대부분의 우라늄이 제거되었다. 우라늄이 제거된 기작은 대부분 미생물 표면에 대한 흡착, 침전 및 광물화에 의한 것이었다. 투과전자현미경으로 관찰한 결과로는 미생물 표면에 흡착되어 점차 결정화되어가는 우라늄이 큰 광물로 성장하고 여러 미생물개체 및 유기분비물과의 결합을 통해 그 크기가 수 ${\mu}m$ 이상으로 커져가는 것을 확인하였다. 이러한 미생물에 의한 우라늄 광물의 성장 및 결합은 방사성폐기물처분장의 우라늄 거동에 큰 영향을 끼칠 수 있으며, 특별히 본 실험에서 관찰한 생지화학적인 금속환원미생물의 역할에 의해 지하 우라늄의 이동이 상당히 지연되는 효과를 거둘 수 있을 것으로 사료된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제11권5호
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• pp.51-58
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• 2006

본 연구에서는 국내에 자생하는 포플러나무중 양황철을 대상으로 토양칼럼에서의 디젤(TPH) 제거 특성 및 식물체에 미치는 독성효과를 평가하였다. 포플러 삽목은 2달간 생장시킨 후 본 실험에 이용되었으며, 다양한 디젤농도(0, 200, 500, 1000, 2000 mg/kg)를 대상으로 60여 일간 진행되었다. 양황철에 의한 디젤 제거 실험에서 낮은 디젤농도에서는 효과적인 처리가 관찰된 반면, 농도가 증가할수록 처리효율은 급격하게 감소하였다. 또한 뿌리생장이 활발한 토양칼럼 하부에서의 처리효율이 상대적으로 높았다. 그리고 양황철 생장과 증산량을 비교하여 디젤의 양황철에 미치는 독성효과의 여부를 검토하였다. 실험기간동안 양황철의 황백화 현상, 뿌리생장 저하, 증산량 감소 현상 등이 관찰 되었다. 또한 토양칼럼 깊이별 측정한 미생물 활성도 결과는 뿌리 생장이 많은 토양 칼럼 하부와 영양염류 및 디젤 분해미생물을 추가로 주입해준 경우가 높았다. 이러한 식물의 정화효과는 근권에 있는 토양미생물에 유용한 뿌리 분비물을 지속적으로 제공함으로써 미생물의 활발한 번식 및 분해활동이 더욱 촉진되는 것으로 보인다.

• 식물병연구
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• 제11권1호
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• pp.80-84
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• 2005

2003년 충북 괴산의 양앵두나무(Prunus avium L.) 재배 포장에서 궤양병 증상이 관찰되었다. 궤양병 증상은 이른 봄에 병든 나무의 주지나 어린 가지 부위가 적갈색으로 마르면서 껍질이 쪼개지고 세균유출액이 흘러 나왔다. 잎에는 갈색 수침상 병반이 나타나고 심하게 감염된 나무의 주지 또는 어린 가지에는 낙엽이 졌다. 궤양병 증상이 심한 주지를 잘라 보면 목질부의 조직들이 파괴되어 불규칙하게 적갈색으로 변색된 전형적인 궤양병 증상이 관찰되었다. 병환부로부터 병원세균을 분리하여 형태적 특성 및 생리${\cdot}$화학적 특성을 조사한 결과 Pseudomonas syringae pv. morsprunorum으로 동정되었다. 병원세균은 양앵두나무와 매실나무의 잎에 병원성을 나타내었지만 복숭아나무, 벚나무와 참다래나무의 잎에는 병원성을 나타내지 않았다. 따라서 P.syringae pv. morsprunorum에 의해 양앵두나무에 발생하는 이 병은 궤양병으로 명명할 것을 제안한다.

• 한국임상수의학회지
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• 제33권5호
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• pp.300-303
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• 2016

An age-unknown, 4.8 kg, male, wild, domestic short-hair cat was presented for left hindlimb lameness. A physical examination revealed a draining tract which was suspected of bite on left calcaneal bone. The left tarsal joint was markedly swollen and exudates were observed around the draining tract. Sequestrum at left calcaneus bone, and osteolysis were identified by radiography. The sequestrum and its surrounding exudative tissue were debrided during surgery and the tissue was submitted for bacterial culture and sensitivity test. The debridement caused a bone defect ($1.5cm{\times}0.5cm{\times}0.5cm$) on the medial left calcaneal bone. Plate and screw fixation was performed to the calcaneus bone as buttress plate. Recombinant human bone morphogenetic protein-2 (rhBMP-2) loaded hydroxyapatite was implanted in the bone defect. Furthermore, Amikacin-impregnated collagen sponges were also placed around bone plate to deliver local antibiotics. A systemic antibiotic treatment regimen based on bacterial culture and sensitivity test results was administered for 4 weeks. The wound properly healed without any signs of infection, and the bone healing was confirmed by radiography. The patient showed normal weight bearing ambulation at 18 weeks after surgery. The use of rhBMP-2 and local antibiotic delivery system is a good surgical option for the one-stage treatment of chronic osteomyelitis.

• Parasites, Hosts and Diseases
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• 제46권3호
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• pp.191-193
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• 2008

Cutaneous leishmaniasis (CL) is a parasitic disease characterized by single or multiple ulcerations. Secondary bacterial infections are one of the complications that can increase the tissue destruction and the resulting scar. To better determine the incidence of real secondary bacterial infections in CL, we designed the current study. This was a cross-sectional study performed in Skin Diseases and Leishmaniasis Research Centre, Isfahan, Iran. A total of 1,255 patients with confirmed CL enrolled in the study. Sterile swaps were achieved for ulcer exudates and scraping was used for non-ulcerated lesions. All samples were transferred to tryptic soy broth medium. After 24 hr of incubation at $37^{\circ}C$ they were transferred to eosin methylene blue agar (EMB) and blood agar. Laboratory tests were used to determine the species of bacteria. Among 1,255 confirmed CL patients, 274 (21.8%) had positive cultures for secondary bacterial infections. The bacteria isolated from the lesions were Staphylococcus aureus in 190 cases (69.3%), coagulase negative Staphylococcus in 63 cases (23.0%), E. coli in 10 cases (3.6%), Proteus sp. in 6 cases (2.2%), and Klebsiella sp. in 5 cases (1.9%). The results show that the overall incidence of secondary bacterial infections in the lesions of CL was 21.8%, considerably high. The incidence of secondary bacterial infections was significantly higher in ulcerated lesions compared with non-ulcerated lesions.

• Parasites, Hosts and Diseases
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• 제51권1호
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• pp.125-128
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• 2013

In April 2010, pruritic symptoms were recognized in 3 privately-owned Siamese cats raised in Gwangju, Korea. Examination of ear canals revealed dark brown, ceruminous otic exudates that contain numerous live mites at various developmental stages. Based on morphological characteristics of adult mites in which caruncles were present on legs 1 and 2 in adult females and on legs 1, 2, 3, and 4 in adult males while the tarsus of leg 3 in both sexes was equipped with 2 long setae, the mite was identified as Otodectes cynotis. Ten ear mite-free domestic shorthaired cats were experimentally infected with O. cynotis to evaluate the efficacy of 10% imidacloprid/1% moxidectin spot-on. Live mites were recovered from 1 of 10 treated cats on day 9 post-treatment (PT) while no live mites were observed from the ear canals of treated cats on days 16 and 30 PT. The efficacy of 10% imidacloprid/1% moxidectin spot-on on O. cynotis in cats was, therefore, 90% on day 9 and 100% on days 16 and 30 PT. This is the first report of otodectosis in 3 cats naturally infested with O. cynotis in Gwang-ju, Korea. Both natural and experimental infestations were successfully treated with 10% imidacloprid/1% moxidectin spot-on.

• 한국환경농학회지
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• 제38권3호
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• pp.185-196
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• 2019

BACKGROUND: This study investigated the effects of rice genetically modified to be resistant against rice blast and rice bacterial blight on the soil microbial community. A comparative analysis of the effects of rice genetically modified rice choline kinase (OsCK1) gene for disease resistance (GM rice) and the Nakdong parental cultivar (non-GM rice) on the soil microbial community at each stage was conducted using rhizosphere soil of the OsCK1 and Nakdong rice. METHODS AND RESULTS: The soil chemistry at each growth stage and the bacterial and fungal population densities were analyzed. Soil DNA was extracted from the samples, and the microbial community structures of the two soils were analyzed by pyrosequencing. No significant differences were observed in the soil chemistry and microbial population density between the two soils. The taxonomic analysis showed that Chloroflexi, Proteobacteria, Firmicutes, Actinobacteria, and Acidobacteria were present in all soils as the major phyla. Although the source tracking analysis per phylogenetic rank revealed that there were differences in the bacteria between the GM and non-GM soil as well as among the cultivation stages, the GM and non-GM soil were grouped according to the growth stages in the UPGMA dendrogram analysis. CONCLUSION: The difference in bacterial distributions between Nakdong and OsCK1 rice soils at each phylogenetic level detected in microbial community analysis by pyrosequencing may be due to the genetic modification done on GM rice or due to heterogeneity of the soil environment. In order to clarify this, it is necessary to analyze changes in root exudates along with the expression of transgene. A more detailed study involving additional multilateral soil analyses is required.

• 한국동물위생학회지
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• 제44권2호
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• pp.103-111
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• 2021

Actinobacillus (A.) pleuropneumoniae is the etiological agent of a porcine pleuropneumonia and have great economic importance to the global swine industry. For recent 5 years, a total of 50 pleuropneumonia cases of 24 pig farms were selected from pig lungs submitted to the College of Veterinary Medicine, Jeju National University using polymerase chain reaction (PCR) analysis. Collected lungs were fixed in 10% neutral phosphate-buffered formalin and processed for histological examination. Serotypes of A. pleuropneumoniae in pneumonic lesions were analyzed by PCR methods. And the antimicrobial susceptibility of A. pleuropneumoniae isolates was determined by a disc diffusion test. Grossly, unilateral distribution of hemorrhagic or necrotic pneumonic lesions was more common than bilateral distribution in lungs. In peracute or acute cases, histopathologic changes were characterized by necrosis, hemorrhage, neutrophils infiltration, vascular thrombosis, widespread edema and fibrinous exudates. Following the acute response, macrophage infiltration, marked fibrosis around zonal necrotic areas, and marked fibrous pleuritis were characteristic in chronic cases. A total of 50 pleuropneumonia were associated with A. pleuropneumoniae serotype 5 in 46 cases (92%), serotype 2 in 3 cases (6%), and both 2 and 5 in 1 case (2%). More than 90% of collected isolates showed high sensitivity to ceftiofur, amoxicillin, and colistin. However, ampicillin, penicillin, and tylosin showed low susceptibility. The results of this study demonstrated that A. pleuropneumoniae serotype 5 was predominant at porcine pleuropneumonia cases in Jeju.

• Journal of Korean Biological Nursing Science
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• 제25권1호
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• pp.63-72
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• 2023

Purpose: This study investigated the knowledge, attitudes, and perceptions of a safe environment, as well as self-reported and observed compliance with the use of personal protective equipment (PPE), among intensive care unit (ICU) nurses. Methods: This study was conducted in October 2021 with 55 nurses working in the medical and surgical ICUs of a general hospital in Seoul. A self-reported questionnaire and an observational tool for compliance with the use of PPE were used to collect data. Results: Except for masks, the observed compliance for all other PPE types was lower than the self-reported compliance. Male nurses showed significantly higher observed compliance than female nurses. Self-reported compliance with PPE use, including "when there is a possibility of contact with objects contaminated with blood or body fluids, mucous membranes, damaged skin, or contaminated skin" (r = .23, p = .015) and "when there is a possibility of contact with blood, body fluids, secretions, or exudates" (r = .27, p = .004) showed significant correlations with knowledge of PPE. In the results for self-reported compliance with PPE use, gown use had a significant correlation with knowledge (r = .24, p < .001) and perceptions of a safe environment (r = .15, p = .016) for PPE, and gloves showed significant correlations with attitudes (r = .14, p = .024) and perceptions of a safe environment (r = .18, p = .003). Conclusion: The observed compliance with PPE use tended to be lower than the self-reported compliance among ICU nurses. It is necessary to develop and apply an effective educational program that can enhance improve actual compliance with PPE use among intensive care unit nurses.

• The Plant Pathology Journal
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• 제39권1호
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• pp.123-135
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• 2023

Previously, Pseudomonas plecoglossicida YJR13 and Pseudomonas putida YJR92 from a sequential screening procedure were proven to effectively control Phytophthora blight caused by Phytophthora capsici. In this study, we further investigated the anti-oomycete activities of these strains against mycelial growth, zoospore germination, and germ tube elongation of P. capsici. We also investigated root colonization ability of the bacterial strains in square dishes, including cell motility (swimming and swarming motilities) and biofilm formation. Both strains significantly inhibited mycelial growth in liquid and solid V8 juice media and M9 minimal media, zoospore germination, and germ tube elongation compared with Bacillus vallismortis EXTN-1 (positive biocontrol strain), Sphingomonas aquatilis KU408 (negative biocontrol strain), and MgSO₄ solution (untreated control). In diluted (nutrient-deficient) V₈ juice broth, the tested strain populations were maintained at >10⁸ cells/ml, simultaneously providing mycelial inhibitory activity. Additionally, these strains colonized pepper roots at a 10⁶ cells/ml concentration for 7 days. The root colonization of the strains was supported by strong swimming and swarming activities, biofilm formation, and chemotactic activity towards exudate components (amino acids, organic acids, and sugars) of pepper roots. Collectively, these results suggest that strains YJR13 and YJR92 can effectively suppress Phytophthora blight of pepper through direct anti-oomycete activities against mycelial growth, zoospore germination and germ tube elongation. Bacterial colonization of pepper roots may be mediated by cell motility and biofilm formation together with chemotaxis to root exudates.