• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.15-15
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• 2014

Fusarium graminearum (teleomorph Gibberella zeae) is an important plant pathogen that causes head blight of major cereal crops such as wheat, barley, and rice, as well as causing ear and stalk rot on maize worldwide. Plant diseases caused by this fungus lead to severe yield losses and accumulation of harmful mycotoxins in infected cereals [1]. Fungi utilize spore production as a mean to rapidly avoid unfavorable environmental conditions and to amplify their population. Spores are produced sexually and asexually and their production is precisely controlled. Upstream developmental activators consist of fluffy genes have been known to orchestrate early induction of condiogenesis in a model filamentous fungus Aspergillus nidulans. To understand the molecular mechanisms underlying conidiogenesis in F. graminearum, we characterized functions of the F. graminearum fluffy gene homologs [2]. We found that FlbD is conserved regulatory function for conidiogenesis in both A. nidulans and F. graminearum among five fluffy gene homologs. flbD deletion abolished conidia and perithecia production, suggesting that FlbD have global roles in hyphal differentiation processes in F. graminearum. We further identified and functionally characterized the ortholog of AbaA, which is involved in differentiation from vegetative hyphae to conidia and known to be absent in F. graminearum [3]. Deletion of abaA did not affect vegetative growth, sexual development, or virulence, but conidium production was completely abolished and thin hyphae grew from abnormally shaped phialides in abaA deletion mutants. Overexpression of abaA resulted in pleiotropic defects such as impaired sexual and asexual development, retarded conidium germination, and reduced trichothecene production. AbaA localized to the nuclei of phialides and terminal cells of mature conidia. Successful interspecies complementation using A. nidulans AbaA and the conserved AbaA-WetA pathway demonstrated that the molecular mechanisms responsible for AbaA activity are conserved in F. graminearum as they are in A. nidulans. F. graminearum ortholog of Aspergillus nidulans wetA has been shown to be involved in conidiogenesis and conidium maturation [4]. Deletion of F. graminearum wetA did not alter mycelial growth, sexual development, or virulence, but the wetA deletion mutants produced longer conidia with fewer septa, and the conidia were sensitive to acute stresses, such as oxidative stress and heat stress. Furthermore, the survival rate of aged conidia from the F. graminearum wetA deletion mutants was reduced. The wetA deletion resulted in vigorous generation of single-celled conidia through autophagy-dependent microcycle conidiation, indicating that WetA functions to maintain conidia dormancy by suppressing microcycle conidiation in F. graminearum. In A. nidulans, FlbB physically interacts with FlbD and FlbE, and the resulting FlbB/FlbE and FlbB/FlbD complexes induce the expression of flbD and brlA, respectively. BrlA is an activator of the AbaA-WetA pathway. AbaA and WetA are required for phialide formation and conidia maturation, respectively [5]. In F. graminearum, the AbaA-WetA pathway is similar to that of A. nidulans, except a brlA ortholog does not exist. Amongst the fluffy genes, only fgflbD has a conserved role for regulation of the AbaA-WetA pathway.

• Radiation Oncology Journal
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• v.28 no.4
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• pp.224-230
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• 2010

Purpose: We designed the aft-multiple-slit (AMS) system to reduce scatter in cone-beam computed tomography (CBCT). As a preliminary study, we performed a Monte Carlo N-Particle Transport Code (MCNP) simulation to verify the effectiveness of this system. Materials and Methods: The MCNPX code was used to build the AMS geometry. An AMS is an equi-angled arc to consider beam divergence. The scatter-reduced projection images were compared with the primary images only and the primary plus scatter radiation images with and without AMS to evaluate the effectiveness of scatter reduction. To obtain the full 2 dimensional (2D) projection image, the whole AMS system was moved to obtain closed septa of the AMS after the first image acquisition. Results: The primary radiation with and without AMS is identical to all the slit widths, but the profiles of the primary plus scattered radiation varied according to the slit widths in the 2D projection image. The average scatter reduction factors were 29%, 15%, 9%, and 8% when the slit widths were 5 mm, 10 mm, 15 mm, and 20 mm, respectively. Conclusion: We have evaluated the scatter reduction effect of the AMS in CBCT imaging using the Monte Carlo (MC) simulations. A preliminary study based on the MCNP simulations showed a mount of scatter reduction with the proposed system.

• Korean Journal of Veterinary Research
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• v.25 no.2
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• pp.113-123
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• 1985

This paper dealt with the distribution of normal mast cells in the spleen, liver and lung on cattle, horses, pigs and dogs, and also degranulation of mast cells in the dogs infected with Rompun (2% Xylazine HCl). The results observed are summarized as follows. Normal mast cells were distributed in spleen, liver and lung on cattle, horse, pig and dog. Mast cells were observed in both red pulp and surroundings of white pulp of the spleen in horse, in the white pulp of the spleen in cattle, in the trabeculae of the spleen in pigs, and in white pulp and red pulp of the spleen in dogs, respectively. Mast cells were observed in the portal triad of the liver in cattle and horses, in both portal triad and interlobular connective tissues of the liver in pigs, and not only the portal triad but also walls of the sinusoids and the central veins in dogs. A large number of mast cells were observed in the interlobular septa and peribronchioles of lung on all the species in this experiment. The mast cells are more numerous in the lungs than other organs. Author considers that numbers of normal mast cells distributed in the tissue is related to the dosage of Rompun in animal. The degranulation of mast cells were observed in the subcutaneous tissues of dog intramuscularly injected with Rompun(0.5ml/times) for 4 or 5 times and subcutaneously injected with Rompun(0.3ml/times) for 4 times. In dog intradermally injected with 0.1ml of Rompun, mast cells were decreased in number at 30 minutes and markedly decreased in number at 2 hours, but more or less increased in number at 3 hours after injection. In addition, the granules of the mast cells were decreased in number at 30 minutes and marked degranulation of the mast cells were recognized at 2 hours after injections, but normal mast cells begun to appear in subcutaneous tissue with the lapse of time from 3 hours after injection. There was also observed local infiltration of neutrophils in subcutaneous tissues of dogs intradermally injected with 0.1ml of Rompun at 30 minutes. At 2 hours after injection, numerous neutrophils and a small number of eosinophils were observed in the site of injection. Conclusionally, Rompun was regarded as a factor which causes the degranulateon of mast cell and the authors considered that histamine released from the mast cells by Rompun might cause relaxation of skeletal muscle.

• Weed & Turfgrass Science
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• v.5 no.2
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• pp.101-104
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• 2016

Curvularia leaf blight of creeping bentgrass (Agrostis stolonifera) putting green by caused Curvularia trifolii was observed in Hapcheon, Korea. In July to September 2014, curvularia leaf blight developed on leaf blades of creeping bentgrass as small water-soaked lesions that subsequently turned into dark-colored, necrotic spots. The spots were expanded and became gray, grayish-brown, or light brown, circular to oblong lesions with purple to dark brown borders that often were surrounded by a yellow halo. The necrotic lesions coalesced, became irregular in shape and caused tip or complete blighting of the leaves. Blighted leaf blades appeared grayish-white to tan. The fungus was identified by morphological characters and 16S rDNA sequencing as C. trifolii. Conidia of the pathogen were short, with predominantly 3-septa, straight or often curved, with end cells frequently paler than intermediate cells. Size of the 3-septate conidia in culture are $26{\sim}28{\times}11{\sim}12{\mu}m$. Pathogenicity of the fungus was proved by artificial inoculation on the host. This is the first report of C. trifolii causing leaf blight on creeping bentgrass in Korea.

• Korean journal of applied entomology
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• v.53 no.3
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• pp.209-215
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• 2014

This study was performed to monitor the seasonal occurrence of Pseudococcus comstocki (Kuwana) by using pheromone traps and to test a mating disruption technique to control this pest in pear orchards. We compared the attractiveness of rubber septa loaded with 1.5 and 3.0 mg of the pheromone, 2,6-dimethyl-1,5-heptadien-3-yl acetate. A total of 1,021 and 1,431 males were caught in traps baited with 1.5 mg and 3 mg of the pheromone, respectively. The numbers of males caught were not affected by trap color, although yellow traps were more attractive than white traps. In 2012, P. comstocki males were captured between June and October, with peaks in late June, early August, and late September. In 2013, the males were trapped between June and October, with peaks in middle June, late July, and late September. In pheromone mating disruption tests, catches were reduced by 17.7, 65.3, and 62.9% in orchards treated with 450, 900, and 1,350 mg per 10 a of the pheromone, respectively. At harvest, 3.4, 2.9, and 4.8% of fruits in orchards treated with 450, 900, and 1,350 mg per 10 a were damaged by P. comstocki, while 9.5% were damaged in the control orchard.

• Tuberculosis and Respiratory Diseases
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• v.51 no.6
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• pp.597-602
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• 2001

A 47-years-old woman presented with a 2-month history of a dry mouth and dry cough. The patient had been taking medication for Sj$\ddot{o}$gren's syndrome for approximately 7 years. The chest radiography showed multiple cystic lesions and a hazy density in both lower lung fields. The HRCT showed a diffuse ground glass like appearance and multiple variable sized cystic lesions in both lung fields. After medication, the symptoms were aggravated. Bronchoscopy was preformed with a transbronchial lung biopsy. The biopsies showed an infiltration of lymphocytes, neutrophils, monocytes and histiocytes through the interstitial space of the alveola and a widening of the alveolar septa. However, the histological findings of the cysts were not obtained. Sj$\ddot{o}$gren's syndrome is a slowly progressive inflammatory autoimmune disease, which is characterized by lymphocyte mediated destruction of the exocrine glands, with pulmonary involvement in approximately 19-65%, High-resolution CT is a sensitive technique for assessing the pulmonary involvement in patients with Sj$\ddot{o}$gren's syndrome. Although a lung biopsy is not always necessary for establishing a diagnosis of an interstitial lung disease in Sj$\ddot{o}$gren's syndrome. A lung biopsy may reveal a wide spectrum of changes ranging from a mild inflammatory response to end stage fibrosis with honeycombing. Because of the predominantly peribronchiolar inflammatory infiltration and inspissated secretions the cysts were suspected to have been formed by the ball-valve phenomen. However, no definite evidence was obtained.

• Tuberculosis and Respiratory Diseases
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• v.40 no.2
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• pp.185-191
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• 1993

Background: Intercellular adhesion molecule-1(ICAM-1) is a 90 kD surface glycoprotein, associated with ${\alpha}_L{\beta}_2$ and ${\alpha}_M{\beta}_2$ subunit of integrins, that serve as cell-cell and cell-substratum adhesion molecules and help regulate cellular morphology, differentiation, and proliferation. The adhesion molecules likely play important roles in maintaining the normal structure and function of the lung. ICAM-1 system among many cell adhesion molecules is importantly issuing in the pathogenesis of idiopathic pulmonary fibrosis. Methods : By using $IgG_1$ monoclonal antibody for ICAM-1, we investigated immunohistochemically the expression of ICAM-1 in the formalin-fixed, paraffin-embedded tissue sections of the 3 normal cases and 6 pieces of tissues taken 3 cases with idiopathic pulmonary fibrosis. Results : In the 3 normal cases, the expressions of ICAM-1 were not discernible. Up-regulation of the ICAM-1 expression was showed in the interstitial fibroblast cells of alveolar septa in 5 pieces and proliferated alveolar pneumocytes in 1 piece among 6 pieces of tissues taken 3 cases with idiopathic pulmonary fibrosis. Conclusion : It was concluded from these findings that up-regulation of the ICAM-1 expression may be related to pathogenesis of idiopathic pulmonary fibrosis.

• The Korean Journal of Mycology
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• v.44 no.3
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• pp.196-200
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• 2016

Symptoms of summer patch were observed on Kentucky bluegrass (Poa pratensis L.) cv. "Midnight II" from mid-June in 2015 in Seoul, Korea. The symptoms appeared as leaf blight, root rot, and frog-eye patch, which are typical of summer patch. To identify the causal agent of these symptoms, a pathogen was isolated from diseased leaves and roots, and the cultural, morphological, and phylogenetic characteristics were analyzed. The isolate reached 50-60 mm on potato dextrose agar (PDA) after 10 days as a white-grey mycelium with septa, and became olive-green or brown from the center. Phialide-like structures were observed at the ends of hyphae, and conidia were rarely observed. A phylogenetic analysis was conducted based on large subunit (LSU) and RNA polymerase II large subunit (RPB1) sequences. According to this analysis, the isolated pathogen was confirmed to be Magnaporthiopsis poae. In a pathogenicity test, summer patch symptoms were observed at 20 days after inoculation using the same grass cultivar. This is the first report of summer patch disease caused by M. poae on cool season grass in Korea.

• Research in Plant Disease
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• v.14 no.1
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• pp.68-70
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• 2008

Brown leaf spots on leaves of kiwifruit(Actinidia deliciosa) were observed at farmers' orchards in Suncheon and Goheung, Jeonnam Province, Korea in June, 2006. They developed to form dark brown ring spots and severely infected leaves resulted in defoliation during the growing season of kiwifruit. Alternaria sp. was isolated from the diseased leaves repeatedly and was identified as Alternaria alternata on the basis of its mycological characteristics on potato dextrose agar and its pathogenicity was confirmed by wound inoculation on healthy leaves of kiwifruit. A. alternata formed gray to dark sooty gray colony and produced numerous conidia on potato dextrose agar. The conidia, commonly in long chains of 5 or more produced on conidiophores, have $3{\sim}5$ transverse and $1{\sim}2$ longitudinal septa and mostly ovoid or obclavate in shape and were pale brown golden brown in color. The condia were $16.5{\sim}42.1{\times}6.7{\sim}19.5\;{\mu}m$ in size and conidiophores were $8.6{\sim}112.7\;{\mu}m$ in length. This is the first report on the brown ring spot on leaves of kiwifruit caused by A. alternata in Korea.

• Journal of Veterinary Clinics
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• v.32 no.6
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• pp.508-510
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• 2015

A 7-year-old castrated male Boston terrier dog was referred due to dyspnea and unilateral cervical mass. On physical examination, mass on left submandibular region was palpated. CT findings revealed this case could be the tumor originated from left lingual vein. The client refused further treatment and the patient expired because of respiratory failure 10 days after presentation. On necropsy, a well-defined firm mass which located in the left side of larynx was detected. Histopathological findings for the mass indicated polygonal tumor cells arranged in nest and separated by fibrovascular septa. We performed immunohistochemisry to evaluate of chromogranin A and tumor cells showed positive immunoreactivity for chromogranin A. Based on computed tomography (CT), histopathological and immunohistochemical findings, this case was definitely diagnosed to paraganglioma of the body on the lingual vein. This report describes the clinical findings, CT imaging characteristics, histopathologic and immunohistochemical features of paraganglioma arised from lingual vein in a dog.