• The Plant Pathology Journal
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• 제33권2호
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• pp.206-211
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• 2017

The effect of temperature on the rate of systemic infection of potatoes (Solanum tuberosum L. cv. Chu-Baek) by Potato virus Y (PVY) was studied in growth chambers. Systemic infection of PVY was observed only within the temperature range of $16^{\circ}C$ to $32^{\circ}C$. Within this temperature range, the time required for a plant to become infected systemically decreased from 14 days at $20^{\circ}C$ to 5.7 days at $28^{\circ}C$. The estimated lower thermal threshold was $15.6^{\circ}C$ and the thermal constant was 65.6 degree days. A systemic infection model was constructed based on experimental data, using the infection rate (Lactin-2 model) and the infection distribution (three-parameter Weibull function) models, which accurately described the completion rate curves to systemic infection and the cumulative distributions obtained in the PVY-potato system, respectively. Therefore, this model was useful to predict the progress of systemic infections by PVY in potato plants, and to construct the epidemic models.

• Journal of Periodontal and Implant Science
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• 제33권1호
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• pp.113-126
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• 2003

• 가정간호학회지
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• 제23권2호
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• pp.155-165
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• 2016

Purpose: The purpose of this study was to investigate factors influencing health workers' infection management behavior in long-term care facilities. Methods: A descriptive cross-sectional survey was conducted with 180 health workers who are employed in long-term care facilities. The data were collected from April, 25 until July, in 2016. Results: Infection management behavior positively correlated with the perceived importance of infection management (r=.77, p<.001), but role conflict negatively correlated with infection management behavior (r=.28, p<.001). The hierarchical regression model with general characteristics (first step) and perceived importance of infection management, work environment, and role conflict (second step) against infection management behavior was statistically significant (F=31.93, p<.001). This model could explain 62.8% of infection management behavior ($R^2=.62$, ${\Delta}R^2=.39$). Particularly, perceived importance of infection management was identified as factors influencing infection management behavior(${\beta}=.70$, p<.001). Conclusion: The findings of this study imply that systemic education about infection control and monitoring should be considered, so as to encourage proper infection management behaviors among health workers in long-term care facilities.

• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2002년도 추계학술대회
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• pp.40-50
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• 2002

Fruit fly, Drosophila melanogaster has developed efficient immune mechanisms to prevent microbial infection, which are consisted of cellular and humoral responses. During the systemic or local infection, two distinct pathways (Toll and Imd) play major roles in antimicrobial peptide synthesis. The Toll pathway is required to defend Gram-positive bacterial and fungal infections, whereas the Imd pathway is important in Gram-negative bacterial infection. We have shown that the infection of the opportunistic Gram-negative bacterium, Pseudomonas aeruginosa strain PA14 (PA14) into fly dorsal thorax can kill the flies within 48 h ($100\%$ mortality) in our optimized infection condition, suggesting that the PA14 strain can cause disease progress in fly model system. We found that flies carrying a constitutively activated mutant form of the Toll receptor $(Tl^{10b})$ showed increased resistance to P. aeruginosa infection and that flies carrying mutations in the Toll signaling pathway as well as in the Imd signaling pathway was more susceptible to PA14 infection. All these results imply that the Toll pathway might be important in the resistance to this pathogenic Gram-negative bacterial infection.

• The Plant Pathology Journal
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• 제32권4호
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• pp.357-362
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• 2016

ALD1 (ABERRANT GROWTH AND DEATH2 [AGD2]-LIKE DEFENSE1) is one of the key defense regulators in Arabidopsis thaliana and Nicotiana benthamiana. In these model plants, ALD1 is responsible for triggering basal defense response and systemic resistance against bacterial infection. As well ALD1 is involved in the production of pipecolic acid and an unidentified compound(s) for systemic resistance and priming syndrome, respectively. These previous studies proposed that ALD1 is a potential candidate for developing genetically modified (GM) plants that may be resistant to pathogen infection. Here we introduce a role of ALD1-LIKE gene of Oryza sativa, named as OsALD1, during plant immunity. OsALD1 mRNA was strongly transcribed in the infected leaves of rice plants by Magnaporthe oryzae, the rice blast fungus. OsALD1 proteins predominantly localized at the chloroplast in the plant cells. GM rice plants over-expressing OsALD1 were resistant to the fungal infection. The stable expression of OsALD1 also triggered strong mRNA expression of PATHOGENESIS-RELATED PROTEIN1 genes in the leaves of rice plants during infection. Taken together, we conclude that OsALD1 plays a role in disease resistance response of rice against the infection with rice blast fungus.

• Mycobiology
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• 제47권2호
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• pp.207-216
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• 2019

Talaromyces marneffei is the only dimorphic species in its genus and causes a fatal systemic mycosis named talaromycosis. Our previous study indicated that knockdown of AcuD gene (encodes isocitrate lyase of glyoxylate bypass) of T. marneffei by RNA interference approach attenuated the virulence of T. marneffei, while the virulence of the AcuD knockout strains was not studied. In this study, T. marneffei-zebrafish infection model was successfully established through hindbrain microinjection with different amounts of T. marneffei yeast cells. After co-incubated at $28^{\circ}C$, the increasing T. marneffei inoculum doses result in greater larval mortality; and hyphae generation might be one virulence factor involved in T. marneffei-zebrafish infection. Moreover, the results demonstrated that the virulence of the ${\Delta}AcuD$ was significantly attenuated in this Zebrafish infection model.

• Journal of Microbiology and Biotechnology
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• 제18권3호
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• pp.591-599
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• 2008

A murine model immunized by systemic and mucosal delivery of plasmid DNA vaccine expressing glycoprotein B (pCIgB) of pseudorabies virus (PrV) was used to evaluate both the nature of the induced immunity and protection against a virulent virus. With regard to systemic delivery, the intramuscular (i.m.) immunization with pCIgB induced strong PrV-specific IgG responses in serum but was inefficient in generating a mucosal IgA response. Mucosal delivery through intranasal (i.n.) immunization of pCIgB induced both systemic and mucosal immunity at the distal mucosal site. However, the levels of systemic immunity induced by i.n. immunization were less than those induced by i.m. immunization. Moreover, i.n. genetic transfer of pCIgB appeared to induce Th2-biased immunity compared with systemic delivery, as judged by the ratio of PrV-specific IgG isotypes and Th1- and Th2-type cytokines produced by stimulated T cells. Moreover, the immunity induced by i.n. immunization did not provide effective protection against i.n. challenge of a virulent PrV strain, whereas i.m. immunization produced resistance to viral infection. Therefore, although i.n. immunization was a useful route for inducing mucosal immunity at the virus entry site, i.n. immunization did not provide effective protection against the lethal infection of PrV.

• Journal of Korean Neurosurgical Society
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• 제67권2호
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• pp.177-185
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• 2024

Objective : Delayed cerebral ischemia (DCI) is a major cause of disability in patients who survive aneurysmal subarachnoid hemorrhage (aSAH). Systemic inflammatory markers, such as peripheral leukocyte count and systemic immune-inflammatory index (SII) score, have been considered predictors of DCI in previous studies. This study aims to investigate which systemic biomarkers are significant predictors of DCI. Methods : We conducted a retrospective, observational, single-center study of 170 patients with SAH admitted between May 2018 and March 2022. We analyzed the patients' clinical and laboratory parameters within 1 hour and 3-4 and 5-7 days after admission. The DCI and non-DCI groups were compared. Variables showing statistical significance in the univariate logistic analysis (p<0.05) were entered into a multivariate regression model. Results : Hunt-Hess grade "4-5" at admission, modified Fisher scale grade "3-4" at admission, hydrocephalus, intraventricular hemorrhage, and infection showed statistical significance (p<0.05) on a univariate logistic regression. Lymphocyte and monocyte count at admission, SII scores and C-reactive protein levels on days 3-4, and leukocyte and neutrophil counts on days 5-7 exhibited statistical significance on the univariate logistic regression. Multivariate logistic regression analysis revealed that monocyte count at admission (odds ratio [OR], 1.64; 95% confidence interval [CI], 1.04-2.65; p=0.036) and SII score at days 3-4 (OR, 1.55; 95% CI, 1.02-2.47; p=0.049) were independent predictors of DCI. Conclusion : Monocyte count at admission and SII score 3-4 days after rupture are independent predictors of clinical deterioration caused by DCI after aSAH. Peripheral monocytosis may be the primer for the innate immune reaction, and the SII score at days 3-4 can promptly represent the propagated systemic immune reaction toward DCI.

• Biomolecules & Therapeutics
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• 제19권4호
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• pp.466-471
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• 2011

Allergic asthma is complex inflammatory airway disorder caused by genetic and environmental factors. Sulfamethoxazole, a sulfonamide, is the cause of drug rash with eosinophilia and systemic symptoms syndrome. Parasites infection also related with eosinophilia and allergic diseases. In the present study, we investigated the modulating effects of parasitic derivative and sulfamethoxazole (SMX) on allergic airway inflammation in the ovalbumin (OVA)-induced murine asthma model. Histopathological changes, cytokine secretion, and total and allergen-specific IgE were investigated. BALB/c mice were treated with Ascaris suum extract or SMX for 4 weeks before sensitized and challenged to ovalbumin. Pre-treatment of Ascaris suum extract decreased allergic inflammation in lung tissue and IL-4, total IgE, and OVA-specific IgE levels in bronchoalveolar lavage fluid. However, pre-treatment of SMX did not show any effects on allergic airway inflammation. These results indicate that parasitic infection has protective effects on allergic asthma, but the sulfamamides may not relate with allergic asthma.

• Pediatric Infection and Vaccine
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• 제24권2호
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• pp.102-107
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• 2017

목적: 가와사키병의 환아뿐만 아니라, 다른 전신 염증 질병의 환아들에 관상동맥 병변(coronary arterial lesion [CAL])의 발생이 보고되었다. 본 연구에서는 전형적인 전신염증반응증후군(systemic inflammatory response syndrome [SIRS])의 소견을 보이는 패혈증 마우스 모델에서 가와사키병 환아에게 관찰되는 CAL이 발생하는지 확인하고자 하였다. 방법: 생후 6주 C57BL/6 마우스에 내독소를 복강내주사하여 SIRS를 보이는 패혈증 모델을 유도하였다. 대조군과 패혈증군의 주요 장기의 조직학적 소견을 비교하였고 패혈증 마우스에서 CAL을 찾기 위한 시도를 하였다. 결과: 대조군과 비교하여, 염증세포의 침윤이 패혈증 마우스의 심장, 간, 신장에 상대적으로 증가하였다. 패혈증 마우스의 심장에서 심근(심근염)과 심장 주위 연조직에 림프구 침윤을 확인하였다. 또한, 패혈증 마우스의 관상동맥을 관찰하였지만, CAL을 확인할 수는 없었다. 결론: 본 연구에서 패혈증 마우스 모델에서 CAL의 존재를 확인하는 것은 실패하였다. 하지만, SIRS를 유발하는 많은 종류의 원인 질병에서 CAL이 발생한다는 것은 잘 알려져 있다. 가와사키병을 포함한 다양한 전신 염증 질병에 나타나는 CAL의 임상적 의미에 대한 연구가 필요할 것이다.