• Journal of Microbiology and Biotechnology
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• 제10권5호
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• pp.694-699
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• 2000

Serratia marcescens IRBG500 and Herbaspirillum seropedicae Z67 grow endophytically in rice. The ability of these bacteria to colonize rice grown under increased nutrient availability was assessed in variety IR72 using strains marked with transposon-based gusA. The endophytic colonization was monitored via bacterial enumeration and histochemical visualization of GUS expression of bacteria in plant tissues. Rhizoplane and endophytic colonization by both bacteria was significantly inhibited in the rice plants grown in the presence of 10 mM $NH_4Cl$. In contrast, the addition of 10 mM $KNO_3$ showed no adverse effect on colonization. Increasing the concentration of $Ca^{2+}$ to 5 mM significantly reduced endophytic colonization by both bacterial strains, whereas the addition of 0.5 mM $Fe^{2+}$ substantially lowered the colonization of roots by S. marcescens IRBG500 but showed no effect on colonization by H. seropedicae Z67. Taken together, these finding suggest that, like in legume-rhizobial symbiosis as well as plant-pathogen interactions, nutrient status, particularly $NH_4^+$ and $Ca^{2+}$ concentrations in the surrounding medium, plays an important role in the regulation of endophytic infection and colonization processes in rice.

• 대한간호학회지
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• 제43권2호
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• pp.287-295
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• 2013

Purpose: The purpose of this study was to identify vancomycin-resistant enterococcus (VRE) colonization rate in patients admitted to the intensive care unit (ICU), associated risk factors and clinical outcomes for VRE colonization. Methods: Of the 7,703 patients admitted to the ICUs between January, 2008 and December, 2010, medical records of 554 VRE colonized and 503 uncolonized patients were reviewed retrospectively. To analyzed the impact of colonization on patients' clinical outcomes, 199 VRE colonized patients were matched with 199 uncolonized patients using a propensity score matching method. Results: During the study period, 567 (7.2%) of the 7,703 patients were colonized with VRE. Multivariate analysis identified the following independent risk factors for VRE colonization: use of antibiotics (odds ratio [OR]=3.33), having bedsores (OR=2.92), having invasive devices (OR=2.29), methicillin-resistant Staphylococcus aureus co-colonization (OR=1.84), and previous hospitalization (OR=1.74). VRE colonized patients were more likely to have infectious diseases than uncolonized patients. VRE colonization was associated with prolonged hospitalization and higher mortality. Conclusion: Strict infection control program including preemptive isolation for high-risk group may be helpful. Further research needs to be done to investigate the effects of active surveillance program on the incidence of colonization or infection with VRE in the ICU.

• 한국산림과학회지
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• 제98권5호
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• pp.539-547
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• 2009

This study was conducted to investigate the arbuscular mycorrhizal fungal biodiversity, spore density and root colonization in relation to site ages at expressway cut-slopes in Korea. Stabilization of exposed surface involved soil amendments and spraying seed mixture of turf grasses and/or nitrogen-fixing shrub species. Eighteen sites were selected with varying ages (2 to 16 years). Soil samples collected in October from each site were analyzed for fungal diversity and spore counts. Fine root samples from the plants were assayed for fungal colonization. Of the total 37 plants inspected in the sites, 26 species had endomycorrhizal colonization with an average root colonization rate of 18%, and with a range from 1 to 67%. The average endomycorrhizal colonization rate of initially introduced Festuca arundinacea which became the most dominant grass in later stage showed 22.8%, while that of Lespedeza bicolor which became the most dominant woody species were 21.6%. Naturally-invading Robinia pseudoacacia showed higher colonization rate in the old sites. Although site age did not show significant effects on fungal diversity, the root colonization rates of initially introduced plants decreased with the site aging, while those of invading plants increased with aging of the sites. The soil chemical properties, pH, N, and P contents, were negatively correlated with spore density, root colonization and endomycorrhizal species diversity. A total of forty arbuscular mycorrhizal fungal species in seven genera were identified. Of the 40 species, Acaulospora lacunosa, Glomus aggregatum, Glomus constrictum, Scutellospora erythropa, and Acaulospora spinosa were the five most dominant species in the decreasing order.

• 대한한방내과학회지
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• 제40권5호
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• pp.974-982
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• 2019

Objective: Modern medicine offers no efficient way to clear colonization by vancomycin-resistant enterococci (VRE). However, VRE decolonization needs to be cleared as soon as possible to prevent VRE transmission. This study reports six cases in which the duration of vancomycin resistant enterococcus (VRE) colonization was reduced by Bojungikki-tang-gami. Methods: Six inpatients with VRE colonization were administered Bojungikki-tang-gami and continuously followed up with cultures. After three negative stool cultures, the patients were declared cleared of VRE colonization. We recorded the duration of VRE colonization. Results: The duration of VRE colonization in the six patients was a mean of 58 days and a median of 45 days. This was shorter than the duration reported in most previous studies. No side effects were noted. Conclusions: The findings of this study suggest that Bojungikki-tang-gami might be effective in shortening the duration of VRE colonization.

• Mycobiology
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• 제45권1호
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• pp.15-19
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• 2017

This study proposed a rapid method to quantify the colonization rate of arbuscular mycorrhizal fungi (AMF) in plant roots. The method involved the use of an image analysis software (WinRHIZO Pro). The colonization rate is defined as the ratio of the fungal body to the plant root area in a micrograph. Three seedlings of Chengiopanax sciadophylloides, a woody species that accumulates radiocesium, were collected from a secondary forest in the Yamakiya district of Kawamata, Fukushima Prefecture during May-September 2014. The colonization of AMF structures was examined under a light microscope, and the percentage of colonization was determined using the WinRHIZO method. The superiority of the new method was verified by comparing with a modified grid-line intersect method. The colonization of AMF was confirmed in all the seedlings, and a significant coefficient of determination ($R^2=0.94$) was found with both the methods. The results suggested that the WinRHIZO method is reliable for estimating the colonization of AMF in C. sciadophylloides.

• Neonatal Medicine
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• 제18권2호
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• pp.272-279
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• 2011

목적: 최근 신생아 집중 치료실(neonatal intensive care unit, NICU)에 입원한 신생아들의 병원내 감염 중 그람 음성 간균(Gram negative bacilli, GNB)에 의한 패혈증이 증가하고 있다. NICU에서 정기적인 대변의 감시 배양을 통해 GNB에 의한 장관 집락화가 같은 균에 의한 패혈증으로 이행되는 지를 확인하고, 집락화된 GNB 병원균의 종류를 확인하며 집락화에 관여하는 위험인자를 조사하고자 하였다. 방법: 2007년 10월부터 2008년 5월까지 고신대학교 복음병원 신생아 집중치료실에 입원한 86명의 환아를 대상으로 하였다. 모든 환아에게 총 3회의 대변 채집을 계획하였는데, 출생 후 첫 대변과 2주 간격으로 2회 채집을 계획하였다. 장관의 GNB 집락화와 관련된 위험 인자들은 대상 환아들의 의무기록을 열람하거나 연관된 논문의 고찰을 통해 설정하였다. 결과: 86명의 환아 중 22명(25.6%)이 GNB에 의한 장관 집락화가 있었으나 이 환아들을 퇴원까지 추적하였을 때 GNB로 인한 패혈증은 없었다. Pseudomonas aeruginosa, Enterobcter cloacae, Citrobacter freundii가 가장 많이 분리되었다. 분리된 GNB 중 약 89% (32/36)는 amikacin에 감수성이 있었다. GNB 에 의한 장관 집락화의 가능성은 집락화 당시 수유량이 적을 때 증가한 반면, 첫 수유 시기가 지연될 때 그 가능성은 감소하였다. 결론: 저자들은 NICU에 입원한 신생아에서 장관 감시배양을 통해 장관에 집락화된 GNB를 확인하였으나 연구에 포함된 환아에서 GNB에 의한 패혈증이 발생하지 않았으므로 집락화가 패혈증으로 이행되는 지를 확인할 수는 없었다. 집락화시 적은 수유량(feeding volume at colonization day)이 집락화의 위험요인이었으므로 장관 영양의 진행이 원활하지 않을 경우 장관의 GNB 집락화 가능성을 고려해야 한다.

• Pediatric Infection and Vaccine
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• 제19권3호
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• pp.111-120
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• 2012

목 적 : 단일 병원 신생아입원실에 입원한 신생아를 대상으로 환자의 임상적 특징에 따른 MRSA 보균율을 알아보고, 그 기원을 추정해 보며, MRSA 보균에 영향을 미치는 요소들을 살펴보고자 하였다. 방 법 : 2008년 1월부터 2011년 12월까지 을지대학교 서울 을지병원 신생아 입원실에 입원하여 MRSA 감시배양검사를 시행받은 1,733명의 신생아를 대상으로 의무기록을 후향적으로 조사하였다. MRSA 감시배양검사는 비강, 서혜부, 직장에서 시행하였고, 퇴원 시까지 매주 반복 시행 하였다. MRSA 감시배양결과에 따라서 보균자와 비보균자로 나누었다. 결 과 : 대상환자 1,733명 중에 415명(23.9%)이 MRSA 보균자였다. 제태기간, 출생체중, 분만 방식, 분만전 산모에게 항생제 투여 여부, 출생장소, 입원전 체류 장소에 따라서 MRSA 보균율에 차이를 보였다(P<0.001). 다변량 검사에서 분만전 산모에게 예방적 항생제를 투여하지 않은 경우가 투여한 경우에 비해서 신생아가 MRSA 보균자가 될 위험도가 2.8배(OR=2.77; 95% CI, 1.88-4.07), 출생장소가 외부인 경우가 본원인 경우에 비해서 2.3배(OR=2.28; 95% CI, 1.17-4.42) 높음을 확인하였다. 결 론 : 신생아 입원환자를 대상으로 한 MRSA 보균율은 23.9%로 상대적으로 높은 보균율을 확인하였다. 환자특성을 고려하여 추정한 HA-MRSA 보균율은 51/511명(10%), CA-MRSA 보균율은 309/858명(36%) 이었다. 본병원 신생아에서 MRSA 보균과 연관된 요인은 산모의 예방적 항생제 사용여부와 출생장소임을 확인하였다.

• 기본간호학회지
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• 제15권4호
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• pp.522-530
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• 2008

Purpose: In this study active surveillance culture for ICU patients, in whom the risk of VRE infection was high were conducted, and through this the VRE colonization rate and the characteristics of the colonization were examined and risk factors involved in VRE colonization and acquisition were analyzed. Method: This research was performed with 635 patients admitted to ICU between July 1 and December 31, 2006. Results: On admission to ICU, the VRE colonization rate was 2.36%, 93% identified from active surveillance culture. The VRE colonization rate was significantly higher in those patients with cancer (OR=9.43; 95% CI=1.38${\sim}$62.50; P=.022), liver cirrhosis (OR=55.5; 95% CI=7.29${\sim}$500; P=.005), transferred from other hospitals (OR=200; 95% CI=22.73${\sim}$1000; P=.000), high APACHE II score (OR=1.107; 95% CI=1.010${\sim}$1.213; P=.029), or antibiotics within the last 3 months (OR=15.87; 95% CI=2.27${\sim}$111.11; P=.005). The VRE acquisition rate was 5.2%. It was significantly higher in those who were using a ventilator (OR=26.31; 95% CI=5.13${\sim}$142.86; P=.000), three or more kinds of antibiotics during admission (OR=58.82; 95% CI=16.13${\sim}$200; P=.000), or high APACHE II score (OR=1.16; 95% CI=1.08${\sim}$ 1.24; P=.000). Conclusion: The results of this study show that active surveillance culture can detect VRE colonization on admission to ICU and those who have acquired VRE in ICU. The analyzed VRE colonization and risk factors of VRE acquisition are expected to be useful in establishing guidelines for preventing VRE infection in ICU.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제20권1호
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• pp.47-54
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• 2017

Purpose: Clinical symptoms associated with Clostridium difficile infection (CDI) can vary widely. Carrier state without apparent symptoms is relatively common during infancy. The objective of this study was to determine the association of C. difficile colonization with bowel habit change and the effect of C. difficile colonization treatment on restoration of normal bowel habit. Methods: Between 2006 and 2014, infants at 1 to 12 months of age with diarrhea for more than 2 weeks who did not improve with conservative care were recruited from Gachon University Gil Medical Center. Infants who were followed up for at least 7 days were included. The presence or absence of C. difficile colonization, effect of metronidazole, and other medical records were reviewed. To determine the association between CDI and bowel habit change, logistic regression analysis was used. Results: Of a total of 126 infants, 74 (58.7%) were male patients. Of the 126 patients, 27 (21.4%) had C. difficile colonization. Significant (p<0.05) risk factors for C. difficile colonization included artificial milk feeding (odds ratio [OR], 4.310; 95% confidence interval [CI], 1.564-11.878), prior rotavirus vaccination (OR, 4.322; 95% CI, 1.018-18.349), and antibiotic use (OR, 4.798; 95% CI, 1.430-16.101). There was improvement in bowel habit after metronidazole therapy (OR, 0.34; 95% CI, 0.15-0.79; p<0.05), regardless of the presence or absence of C. difficile colonization, Conclusion: There was no significant correlation between bowel habit change and C. difficile colonization during infancy. However, metronidazole can be used as an optional method to manage functional gastrointestinal disorders.

• Applied Microscopy
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• 제34권2호
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• pp.103-111
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• 2004

수생식물 개구리밥(Spirodela polyrhiza)의 식물체 발달 과정에서 나타나는 미생물과의 상호관계를 주사전자현미경 및 세포학적으로 추적하여 연구하였다. 개구리밥은 부유성 식물로 분화 발달 초기부터 잠수부위에 여러 종류의 박테리아, 남조류, 규조류 등이 서식하였다. 미분화된 어린 식물체에는 성숙 발달한 식물체에 비해 미생물들이 낮은 빈도로 출현하였고, 성숙한 식물체에서는 특히 엽상체 하피에 가장 많은 미생물들이 서식하였으며, 그 다음으로는 점액성 물질이 층을 이루는 근관에 많이 관찰되었다. 반면, 신장 발달 중의 뿌리에는 일반적인 분포를 보였으며, 상피에는 미생물이 거의 분포하지 않는 양상을 보였다. 이들 미생물이 개구리밥 조직 내에 침입하여 식물체에 어떠한 영향을 미치는가를 조사하기 위해 엽상체, 연결사, 뿌리, 근관, 무성생식낭 등의 구조를 세포학적으로 추적한 결과, 어느 부위에서도 조직 내로 미생물이 침입하여 세포를 괴사시키거나 감염시키는 일은 거의 관찰되지 않았다. 그러므로, 개구리밥 식물체의 발달과정에 있어 미생물들은 어떠한 해를 주지 않는 것으로 추정된다. 이후 개구리밥에 서식하는 미생물의 질소고정치를 측정하여 그 기능을 식물체의 세포학적 측면과 접목시켜 연구하면 개구리밥과 미생물과의 상호관계가 공생적인지를 더 확실하게 밝힐 수 있을 것이다.