• The Plant Pathology Journal
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• v.23 no.3
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• pp.203-209
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• 2007

Infection structures were observed using a fluorescence microscope at the penetration sites on the leaves of potato plants pre-inoculated with the bacterial strains Pseudomonas putida TRL2-3, Micrococcus luteus TRK2-2, and Flexibacteraceae bacterium MRL412, which mediated an induced systemic resistance on potato plants against late blight disease caused by Phytophthora infestans. In order to compare the infection structures on the leaves expressing systemic acquired resistance, the leaves of potato plants pre-treated with DL-3-amino butyric acid (BABA) were also observed after challenge inoculation with the same pathogen. The infection structures were investigated. The total number of germination and appressorium formation of P. infestans were counted. Furthermore, the frequencies of fluorescent epidermal cells at the penetration sites, which indicate a defense response of plant cell, were estimated. There were no differences on the germination rates of the fungal cysts among the untreated control, BABA pre-treated, and bacterial strains pre-inoculated plants. However, appressorium formation was slightly decreased on the leaves of BABA pre-treated plants compared to those of untreated as well as bacterial strains pre-inoculated plants. Furthermore, the frequencies of fluorescent cells of BABA pre-treated and bacterial strains pre-inoculated were higher than that of untreated plants, indicating an active defense reaction of the host cells against the fungal attack. On the other hand, the pre-treatment with BABA caused a stronger fluorescent of epidermal cells at the penetration sites compared to the pre-inoculation with the bacterial strains. Interestingly, the frequency of fluorescent cells by BABA, however, was lower than that by the bacterial strains. Based on the results it is suggested that the infection structures showing resistance reaction on the leaves of potato plants were different between by pre-inoculation with bacterial strains and by pre-treatment with BABA against the late blight pathogen.

• Journal of Medicine and Life Science
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• v.15 no.2
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• pp.84-88
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• 2018

The aim was to evaluate different results from using crude incidence rate (CIR) instead of agestandardized incidence rate (AIR) when comparing groups having different age structures. After selecting a report using CIRs, AIRs and their 95% confidence intervals(CI) was calculated from the raw data. The statistically significant difference between CIR and AIR was decided based on AIR's 95% CI. Comparing with CIRs, AIRs were under-estimated. In addition, there were no statistical significance of annual trends(P=0.59). These findings are an additional evidence using AIR when comparing level of occurring infectious diseases on groups with different age structures.

• Korean Journal of Bronchoesophagology
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• v.3 no.1
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• pp.159-163
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• 1997

The complications of deep neck infection have become much less common in the antibiotic era. The vascular complications of deep neck infection can have devasting consequences. Most commonly, the internal carotid artery is involved, although the common carotid and external carotid artery can also be affected.0 the cases of patients with a protracted course, recurrent bleeding, cranial neuropathies, or trismus, the presence of vascular complications must be considered. Appropriate imaging should be carried out to allow the localization of the infection and ascertain the status of the vessels in the neck The vascular structures can be imaged with duplex doppler or color doppler flow ultrasound to see the flow between the mass and vessels. Also angiography plays a key role in the diagnosis and management of vascular complication of deep neck infection. Prompt diagnosis and treatment of these patients is necessary to prevent significant hemmorrhagic complications. We experienced a case of pseudoaneurysm of the common carotid artery secondary to deep neck infection treated successfully with surgical excision in 45-year-old-male.

• The Plant Pathology Journal
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• v.25 no.2
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• pp.113-120
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• 2009

Microscopic study of chili pepper (Capsicum annuum L.) infected with Phytophthora capsici, causing Phytophthora blight of chili pepper, was conducted to compare histological and cytological characteristics in the root and stem of susceptible (C. annuum cv. Bugang) and resistant (C. annuum cv. CM334) pepper cultivars. The susceptible pepper roots and stems were extensively penetrated and invaded by the pathogen initially into epidermal cells and later cortical and vascular cells. Host cell walls adjacent to and invaded by the infecting hyphae were partially dissolved and structurally loosened with fine fibrillar materials probably by cell wall-degrading enzymes of the pathogen. In the resistant pepper, the pathogen remained on root epidermal surface at one day after inoculation, embedded and captured in root exudation materials composed of proteins and polysaccharides. Also the pathogen appeared to be blocked in its progression at the early infection stages by thickened middle lamellae. At 3 days after inoculation, the oomycete hyphae were still confined to epidermal cells of the root and at most outer peripheral cortical cells of the stem, resulting from their invasion blocked by wound periderms formed underneath the infection sites and/or cell wall appositions bounding the hyphal protrusions. All of these aspects suggest that limitation of disease development in the resistant pepper may be due to the inhibition of the pathogen penetration, infection, invasion, and colonization by the defense structures such as root exudation materials, thickened middle lamellae, wound peridems and cell wall appositions.

• Parasites, Hosts and Diseases
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• v.55 no.5
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• pp.561-564
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• 2017

This report describes a dog infected with Hepatozoon canis, the first canine infection in the Republic of Korea. A 2-year-old intact male Maltese dog presented with anorexia and depression. Physical examinations revealed mild dehydration and hyperthermia ($39.8^{\circ}C$), and blood analysis showed pancytopenia. Diff-Quik staining of blood smear specimens showed the presence of ellipsoidal shaped structures (gamonts of H. canis) within a small number of neutrophils. Real-time PCR analysis using whole blood confirmed infection by H. canis. The clinical condition of the dog improved after symptomatic treatment and administration of doxycycline. Although a molecular epidemiologic survey in Korea showed H. canis infection of dogs, to our knowledge this is the first report of a dog infection in Korea molecularly shown to be H. canis.

• 한국균학회소식:학술대회논문집
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• 2015.11a
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• pp.23-23
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• 2015

Rice blast disease caused by M. oryzae is the most devastating fungal disease in rice. During the infection process, M. oryzae secretes a large number of glycosyl hydrolase (GH) proteins into the apoplast to digest host cell wall and assist fungal ingress into host tissues. In this study, we identified a novel M. oryze arabinofuranosidase B (MoAbfB) which is secreted during fungal infection. Live-cell imaging exhibited that fluorescent labeled MoAbfB was highly accumulated in fungal invasive structures such as appressorium, tips of penetration peg, biotrophic interfacial complex (BIC), as well as invasive hyphal tip. Deletion of MoAbfB mutants extended biotrophic phase followed by enhanced disease severity, whereas, over-expression of OsMoAbfB mutant induced rapid defense responses and enhanced rice resistance to M. oryzae infection. Furthermore, exogenous treatment of MoAbfB protein showed inhibition of fungal infection via priming of defense gene expression. We later found that the extract of MoAbfB degraded rice cell wall fragments could also induce host defense activation, suggesting that not MoAbfB itself but oligosaccharides (OGs) derived from MoAbfB dissolved rice cell wall elicited rice innate immunity.

• The Plant Pathology Journal
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• v.19 no.1
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• pp.34-42
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• 2003

The ascomycete Magnaporthe grisea is a pathogen of rice blast and is known to form specialized infection structures called appressoria for successful infection into host cells. To understand the molecular mechanism underlying infection process, appressorium-related genes were identified through global approaches including EST sequencing, differential hybridization, and sup-pression subtractive hybridization. EST database was generated on >2,000 cDNA clones randomly selected from appressorium stage cDNA library. Large number of ESTs showed homology to known proteins possibly involved in infection-related cellular development (attachment, germination, appressorium formation, and colonization) of rice blast fungus. The 1051 ESTs showing significant homology to known genes were assigned to 11 functional categories. Differential hybridization and suppression subtractive hybridization were applied to identify genes showing an appressorium stage specific expression pattern. A number of genes were selected as up-regulated during appressorium formation compared with the vegetative growing stage. Clones from various cDNA libraries constructed in different developmental stages were arrayed on slide glass for further expression profiling study. functional characterization of genes identified from these global approaches may lead to a better understand-ing of the infection process of this devastating plant disease, and the development of novel ways to protect host plant.

• Journal of Microbiology and Biotechnology
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• v.22 no.9
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• pp.1224-1229
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• 2012

Puerarin (P), an isoflavone derived from kudzu roots, has strong biological activities, but its bioavailability is often limited by its low water solubility. To increase its solubility, P was glucosylated by three dextransucrases from Leuconostoc or Streptococcus species. Leuconostoc lactis EG001 dextransucrase exhibited the highest productivity of puerarin glucosides (P-Gs) among the three tested enzymes, and it primarily produced two P-Gs with a 53% yield. Their structures were identified as ${\alpha}$-$_D$-glucosyl-($1{\rightarrow}6$)-P (P-G) by using LC-MS or $^1H$- or $^{13}C$-NMR spectroscopies and ${\alpha}$-$_D$-isomaltosyl-($1{\rightarrow}6$)-P (P-IG2) by using specific enzymatic hydrolysis, and their solubilities were 15- and 202-fold higher than that of P, respectively. P-G and P-IG2 are easily applicable in the food and pharmaceutical industries as alternative functional materials.

• ALGAE
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• v.24 no.4
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• pp.249-256
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• 2009

The occurrence of Laminarionema elsbetiae (Ectocarpaceae, Phaeophyceae), as epi-endophyte of Rhodymenia pseudopalmata (Rhodymeniales, Rhodophyta), described from Santa Isabel, Rawson, Argentina. L. elsbetiae grows in the host tissues forming epi-endophytic relationship in the epidermal, cortical and medullar layers. Epiphytic thalli of L. elsbetiae were unbranched filaments emerging from hostis surface. Reproductive structures of L. elsbetiae on the host were absent. On the contrary, free cultured individuals formed different reproductive structures. Macrozoosporangia containing a single large motile zoospore originated from vegetative cells, they were conical to cylindrical in shape, 30-50 ${\mu}m$ in length and 18-20 ${\mu}m$ in wide. Uniseriate plurilocular zoosporangia were cylindrical shape, 40 ${\mu}m$ in length and 10-13 ${\mu}m$ in wide. Sexual fusion was not seen. In mixed cultures of L. elsbetiae with R. pseudopalmata fronds, L. elsbetiae infected the host, grew as in natural host and, formed macrosporangia between host subcortical cells. Gametophytes of L. elsbetiae were filaments with diffuse growth, branched with a branch pattern alternate or opposite. Gametangia were plurilocular, uni or biseriate and lateral. When mature they contained 2 to 6 isogametes. The presence L. elsbetiae on R. pseudopalmata could be defined as an epi-endophytic relationship. The percentage of infection of R. pseudopalmata thalli by L. elsbetiae was 34%.A25% of the infected thalli presented a low, non-symptomatic level infection, whereas a 62% and a 13% of them exhibited respectively moderate and high indexes of infection.

• Journal of Veterinary Science
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• v.24 no.4
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• pp.53.1-53.12
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• 2023

Background: Mammalian orthoreovirus type 3 (MRV3), which is responsible for gastroenteritis in many mammalian species including pigs, has been isolated from piglets with severe diarrhea. However, the use of pig-derived cells as an infection model for swine-MRV3 has rarely been studied. Objectives: This study aims to establish porcine intestinal organoids (PIOs) and examine their susceptibility as an in vitro model for intestinal MRV3 infection. Methods: PIOs were isolated and established from the jejunum of a miniature pig. Established PIOs were characterized using polymerase chain reaction (PCR) and immunofluorescence assays (IFAs) to confirm the expression of small intestine-specific genes and proteins, such as Lgr5, LYZI, Mucin-2, ChgA, and Villin. The monolayered PIOs and three-dimensional (3D) PIOs, obtained through their distribution to expose the apical surface, were infected with MRV3 for 2 h, washed with Dulbecco's phosphate-buffered saline, and observed. Viral infection was confirmed using PCR and IFA. We performed quantitative real-time reverse transcription-PCR to assess changes in viral copy numbers and gene expressions linked to intestinal epithelial genes and antiviral activity. Results: The established PIOs have molecular characteristics of intestinal organoids. Infected PIOs showed delayed proliferation with disruption of structures. In addition, infection with MRV3 altered the gene expression linked to intestinal epithelial cells and antiviral activity, and these effects were observed in both 2D and 3D models. Furthermore, viral copy numbers in the supernatant of both models increased in a time-dependent manner. Conclusions: We suggest that PIOs can be an in vitro model to study the infection mechanism of MRV3 in detail, facilitating pharmaceutical development.