• Research in Plant Disease
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• v.26 no.2
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• pp.88-94
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• 2020

Recently, the severe dieback of apple trees resulting from soil-borne diseases has occurred in South Korea. The casual agents of dieback were surveyed on 74 apple orchards that had been damaged nationwide in 2016-2019. The number of apple orchards affected alone by Phytophthora rot, violet root rot, and white root rot was 31, 34, and 3, respectively. Also, the total number of mixed infection orchards was 6. Out of 9,112 apple trees affected by dieback, the trees damaged by Phytophthora rot, violet root rot, and white root rot were 3,332, 3,831, and 44, respectively. Moreover, the total number of mixed infection apple trees was 1,905. The provinces mainly affected were Gyeongnam, Gyeongbuk, Chungbuk, and Jeonbuk. The survey on these infected apple orchards will be available to form management strategy for the dieback that had been increased by soil-borne fungal pathogens.

• Archives of Craniofacial Surgery
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• v.19 no.3
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• pp.222-226
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• 2018

A 70-year-old male with a history of diabetes mellitus, hypertension, and coronary stent insertion visited our hospital 7 days after biting his lower lip. Swelling and inflammation had worsened despite debridement and antibiotic treatment. On the 8th hospital day, fungal infection with Candida albicans and superimposed bacterial infection with Klebsiella pneumoniae were found on tissue culture. Extensive necrosis resulted in a defect of approximately 3/4 of the entire lower lip and a full-layer skin defect from the vermilion to the gingivobuccal sulcus at the right corner of the mouth. To correct drooling, incomplete lip sealing, and trismus, staged reconstruction was performed with consideration of cosmetic and functional features. The treatment process using staged reconstruction and antifungal treatment for an extensive lower lip defect caused by fungal stomatitis is described.

• Pediatric Infection and Vaccine
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• v.27 no.3
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• pp.190-197
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• 2020

Laryngotracheobronchitis (LTB) is a common disease in the pediatric population, and it is rarely caused by a fungal infection. Acute respiratory failure caused by fungal LTB mainly occurs in immunocompromised patients, and early diagnosis is closely associated with morbidity and mortality. However, an appropriate diagnosis is challenging for pediatricians because symptoms and signs of LTB caused by Aspergillus spp. are nonspecific. Here, we report a case of progressive respiratory failure caused by pseudomembranous LTB in a child with a suspicion of primary immunodeficiency and highlight the importance of an early investigation, especially in immunocompromised patients.

• 한국균학회소식:학술대회논문집
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• 2015.05a
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• pp.61-61
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• 2015

Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most destructive diseases of rice worldwide. The rice - M. oryzae pathosystem has become a model in the study of plant - fungal interactions due to its economic importance and accumulating knowledge. During the evolutionary arms race with M. oryzae, rice plants evolved a repertoire of Resistance (R) genes to protect themselves from diseases in a gene-for-gene fashion. M. oryzae secretes a battery of small effector proteins to manipulate host functions for its successful infection, and some of them are recognized by host R proteins as avirulence effectors (AVR), which turns on strong immunity. Therefore, the analysis of interactions between AVRs and their cognate R proteins provide crucial insights into the molecular basis of plant - fungal interactions. Rice blast resistance genes Pik, Pia, Pii comprise pairs of protein-coding ORFs, Pik-1 and Pik-2, RGA4 and RGA5, Pii-1 and Pii-2, respectively. In all three cases, the paired genes are tightly linked and oriented to the opposite directions. In the AVR-Pik/Pik interaction, it has been unraveled that AVR-Pik binds to the N-terminal coiled-coil domain of Pik-1. RGA4 and RGA5 are necessary and sufficient to mediate Pia resistance and recognize the M. oryzae effectors AVR-Pia and AVR1-CO39. A domain at the C-terminus of RGA5 characterized by a heavy metal associated domain was identified as the AVR-binding domain of RGA5. Similarly, physical interactions among Pii-1, Pii-2 and AVR-Pii are being analyzed.

• Mycobiology
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• v.36 no.4
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• pp.236-241
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• 2008

The colonization of an arbuscular mycorrhizal fungus Glomus intraradices BEG110 in the soil caused a decrease in disease severity in cucumber plants after fungal inoculation with Colletotrichum orbiculare. In order to illustrate the resistance mechanism mediated by G. intraradices BEG110, infection patterns caused by C. orbiculare in the leaves of cucumber plants and the host cellular responses were characterized. These properties were characterized using transmission electron microscopy on the leaves of cucumber plants grown in soil colonized with G. intraradices BEG110. In the untreated plants, inter- and intra-cellular fungal hyphae were observed throughout the leaf tissues during both the biotrophic and necrotrophic phases of infection. The cytoplasm of fungal hyphae appeared intact during the biotrophic phase, suggesting no defense response against the fungus. However, several typical resistance responses were observed in the plants when treated with G. intraradices BEG110 including the formation of sheaths around the intracellular hyphae or a thickening of host cell walls. These observations suggest that the resistance mediated by G. intraradices BEG110 most often occurs in the symplast of the host cells rather than in the apoplast. In addition, this resistance is similar to those mediated by biotic inducers such as plant growth promoting rhizobacteria.

• The Plant Pathology Journal
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• v.32 no.4
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• pp.281-289
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• 2016

The transcription cofactor Swi6 plays important roles in regulating vegetative growth and meiosis in Saccharomyces cerevisiae. Functions of Swi6 ortholog were also characterized in Fusarium graminearum which is one of the devastating plant pathogenic fungi. Here, we report possible role of FgSwi6 in the interaction between F. graminearum and Fusarium graminearum virus 1 (FgV1) strain DK21. FgV1 perturbs biological characteristics of host fungi such as vegetative growth, sporulation, pigmentation, and reduction of the virulence (hypovirulence) of its fungal host. To characterize function(s) of FgSWI6 gene during FgV1 infection, targeted deletion, over-expression, and complementation mutants were generated and further infected successfully with FgV1. Deletion of FgSwi6 led to severe reduction of vegetative growth even aerial mycelia while over-expression did not affect any remarkable alteration of phenotype in virus-free isolates. Virus-infected (VI) FgSWI6 deletion isolate exhibited completely delayed vegetative growth. However, VI FgSWI6 over-expression mutant grew faster than any other VI isolates. To verify whether these different growth patterns in VI isolates, viral RNA quantification was carried out using qRT-PCR. Surprisingly, viral RNA accumulations in VI isolates were similar regardless of introduced mutations. These results provide evidence that FgSWI6 might play important role(s) in FgV1 induced phenotype alteration such as delayed vegetative growth.

• The Plant Pathology Journal
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• v.37 no.4
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• pp.315-328
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• 2021

Fusarium and Rhizoctonia genera are important pathogens of many field crops worldwide. They are constantly evolving and expanding their host range. Selecting resistant cultivars is an effective strategy to break their infection cycles. To this end, we screened a collection of Medicago truncatula accessions against Fusarium oxysporum, Fusarium solani, and Rhizoctonia solani strains isolated from different plant species. Despite the small collection, a biodiversity in the disease response of M. truncatula accessions ranging from resistant phenotypes to highly susceptible ones was observed. A17 showed relative resistance to all fungal strains with the lowest disease incidence and ratings while TN1.11 was among the susceptible accessions. As an initiation of the characterization of resistance mechanisms, the antioxidant enzymes' activities, at the early stages of infections, were compared between these contrasting accessions. Our results showed an increment of the antioxidant activities within A17 plants in leaves and roots. We also analyzed the responses of a population of recombinant inbred lines derived from the crossing of A17 and TN1.11 to the infection with the same fungal strains. The broad-sense heritability of measured traits ranged from 0.87 to 0.95, from 0.72 to 0.96, and from 0.14 to 0.85 under control, F. oxysporum, and R. solani conditions, respectively. This high estimated heritability underlines the importance of further molecular analysis of the observed resistance to identify selection markers that could be incorporated into a breeding program and thus improving soil-borne pathogens resistance in crops.

• Clinical and Experimental Pediatrics
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• v.50 no.7
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• pp.636-642
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• 2007

Purpose : Fluconazole prophylaxis for very low birth weight (VLBW) infants has been shown to reduce invasive fungal infection and its mortality. This study aims to evaluate the effect of fluconazole prophylaxis in VLBW infants on the incidence and mortality of fungal infection. Methods : VLBW infants with endotracheal intubation and central vascular access admitted to the Neonatal Intensive Care Unit (NICU) at Chonnam University Hospital were enrolled. Twenty eight infants of 7-month baseline period from January to July 2005 ('non-fluconazole group') were compared with 29 infants of a 7-month fluconazole period from January to July 2006 ('fluconazole group'). Results : Gestational age, birth weight, sex, mode of delivery, frequency of twin pregnancy, chorioamnionitis, antenatal steroid and rupture of membranes were similar between the fluconazole and non-fluconazole groups. The rate of extremely low birth weight (ELBW) infants, frequency and duration of prophylactic antibiotics, total parenteral nutrition and umbilical catheters, duration of intralipid, mechanical ventilation and nasal continuous positive airway pressure (CPAP) were also not significant. However, frequency of percutaneous central venous catheterization (PCVC) and intralipid administration, and duration of PCVC were significant between the two groups. The overall incidence and mortality of fungal infection were not different between the two groups. Although the Malassezia infection was increased in the fluconazole group (P<0.05), candida was significantly decreased compared to the non-fluconazole group (P<0.05). Conclusion : Fluconazole prophylaxis in high risk VLBW infants decreased the candida infection significantly. Antifungal prophylaxis is recommended in terms of cost effectiveness, but further study is needed to clarify the reason for the increase of Malassezia infection.

• Journal of Chest Surgery
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• v.38 no.9 s.254
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• pp.656-659
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• 2005

Pulmonary mucormycosis is very rare but has a devastating opportunistic fungal infection in immunocompromised hosts. The infection usually occurs in patients with hematologic malignancy, chronic renal failure, diabetes mellitus, or in solid organ transplant recipients. We experienced a case of pulmonary mucormycosis associated with renal cadeveric allograft recipient who had uncontrolled diabetes mellitus. The patient was successfully treated by surgical resection with Amphotericin B therapy.

• Journal of Chest Surgery
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• v.30 no.10
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• pp.1032-1035
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• 1997

Fungal infection of intracardiac pacing wire is very rare. We experienced a case of patient with functioning transvenous pacemaker lead, inserted 3 years previously, which was completely encased in a large thrombus infected with aspergillus. The lung biopsy also confirmed aspergillus infection.