• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.95.2-96
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• 2003

In order to develop a new microbial fungicide for the control of vegetable diseases using endophytic bacteria, a total of 260 bacterial strains were isolated from fresh tissues of 5 plant species. After they were cultured in broth media, their antifungal activities were screened by in vivo bioassays against Botrytis cinerea(tomato gray mold), Pythium ultimum(cucumber damping-off), Phytopkhora infestans(tomato late blight), Colletotrichum orbiculare(cucumber anthracnose), and Blumeria graminis f. sp. hordei(barley powdery mildew). As the results of screening, 38 bacterial strains showed potent antifungal activities against at least one of 5 plant pathogens. A bacterial strain EB072 displayed potent disease control activities against 3 plant diseases. Among the bacterial strains with a potent antifungal activity against cucunlber anthracnose, three bacterial strains, EB054, EB151 and EB215, also displayed a potent in vitro antifungal activity against C. acutatum, a fungal agent causing pepper anthracnose. A bacterial strain EB215 obtained from roots of cucumber was identified as Burkholderia cepacia based on its physiological and biochemical characteristics and 165 rRNA gene sequence. An antifungal substance was isolated from the liquid cultures of B. cepacia EB215 strain by ethyl acetate partitioning, repeated silica gel column chromatography, and invitro bioassay, Its structural determination is in progress by various instrumental analyses.

• The Plant Pathology Journal
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• v.22 no.1
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• pp.75-89
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• 2006

The actinomycete strain JK-1 that showed strong inhibitory activity against some plant pathogenic fungi and oomycetes was isolated from Jung-bal Mountain in Ko-yang, Korea. The strain JK-1 produced spores singly borne on sporophores and the spores were spherical and 0.9-1.2 11m in diameter. The cell wall of the strain JK-1 contained meso-diaminopimelic acid. The actinomycete strain JK-1 was identified as the genus Micromonospora based on the morphological, physiological, biochemical and chemotaxonomic characteristics. From the 168 rDNA analysis, the strain JK-1 was assigned to M aurantiaca. The antibiotic MA-1 was purified from the culture broth of M aurantiaca JK-1 using various purification procedures, such as Diaion HP20 chromatography, C18 flash column chromatography, silica gel flash column chromatography and Sephadex LH-20 column chromatography. $^{1}H-$, $^{13}C-NMR$ and EI mass spectral analysis of the antibiotic MA-1 revealed that the antibiotic MA-1 is identical to phenylacetic acid. Phenylacetic acid showed in vitro inhibitory effects against fungal and oomycete pathogens Alternaria mali, Botrytis cinerea, Magnaporthe grisea, Phytophthora capsici and yeast Saccharomyces cerevisiae at < 100 $\mug$ $ml^{-1}$. In addition, phenylacetic, acid completely inhibited the growth of Sclerotinia sclerotiorum, Bacillus subtilis, Candida albicans, Xanthomonas campestris pv. vesicatoria at < $\mug$ $ml^{-1}$. Phenylacetic acid strongly inhibited conidial germination and hyphal growth of M grisea and C. orbiculare. Phenylacetic acid showed significantly high levels of inhibitory' effect against rice blast and cucumber anthracnose diseases at 250 $\mug$ $ml^{-1}$. The control efficacies of phenylacetic acid against the two diseases were similar to those of commercial compounds tricyclazole, iprobenfos and chlorothalonil .n the greenhouse.

• International Journal of Industrial Entomology and Biomaterials
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• v.30 no.2
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• pp.64-74
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• 2015

Beetles Protaetia brevitarsis seulensis Kolbe (Coleoptera: Cetoniidae) and Allomyrina dichotoma Linn. (Coleoptera: Scarabaeidae) are widely used in traditional medicine, and the number of insect-rearing farms is increasing in South Korea. The purpose of this study was to establish a multiplex PCR-based assay for rapid simultaneous detection of multiple pathogens causing insect diseases. Six insect parasites such as fungi Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Cordycipitaceae) and Metarhizium anisopliae (Metschn.) Sorokin (Hypocreales: Clavicipitaceae), bacteria Bacillus thuringiensis Berliner (Bacillales: Bacillaceae), Pseudomonas aeruginosa Migula (Pseudomonadales: Pseudomonadaceae), and Serratia marcescens Bizio (Enterobacteriales: Enterobacteriaceae), and Oryctes rhinoceros nudivirus were chosen based on the severity and incidence rate of insect diseases in South Korea. Pathogen-specific primers were designed and successfully applied for simultaneous detection of multiple infectious agents in farm-bred insects P. b. seulensis and A. dichotoma using multiplex PCR and high resolution capillary electrophoresis. Our results indicate that multiplex PCR is an effective and time-saving method for simultaneous detection of multiple infections in insects, and the QIAxcel capillary electrophoresis system is useful for quantitative evaluation of the individual impact of each infectious agent on the severity of insect disease. The approach designed in this study can be utilized for rapid and accurate diagnostics of infection in insect farms.

• The Plant Pathology Journal
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• v.36 no.5
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• pp.398-405
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• 2020

Nutrient manipulation is a promising strategy for controlling plant diseases in sustainable agriculture. Although many studies have investigated the relationships between certain elements and plant diseases, few have comprehensively explored how differing mineral nutrition levels might affect plant-fungal pathogen interactions, namely plant susceptibility and resistance. Here, we systematically explored the effects of the seven mineral elements that plants require in the greatest amounts for normal development on the susceptibility of soybean plants (Glycine max) to Fusarium oxysporum infection in controlled greenhouse conditions. Nitrogen (N) negligibly affected plant susceptibility to infection in the range 4 to 24 mM for both tested soybean cultivars. At relatively high concentrations, phosphorus (P) increased plant susceptibility to infection, which led to severely reduced shoot and root dry weights. Potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), and iron (Fe) induced plant resistance to infection as their concentrations were increased. For K and Ca, moderate concentrations had a positive effect on plant resistance to the pathogen, whereas relatively high doses of either element adversely affected plant growth and promoted disease symptoms. Further experiments were conducted, assessing disease suppression by selected combinations of macro-elements and Fe at screened concentrations, i.e., K (9 mM) plus Fe (0.2 mM), and S (4 mM) plus Fe (0.2 mM). The disease index was significantly reduced by the combination of K plus Fe. In conclusion, this systematic investigation of soybean plant responses to F. oxysporum infection provides a solid basis for future environmentally-friendly choices for application in soybean disease control programs.

• International Journal of Industrial Entomology and Biomaterials
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• v.20 no.1
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• pp.1-5
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• 2010

The studies have been conducted to control the soil borne fungal pathogens viz, Fusarium solani (Mart) Sacc. and Alternaria tenuissima the incitants of root rot and die-back diseases on mulberry stem cuttings planted in the mulberry nurseries and also in established mulberry gardens ten plant extracts with 10% concentration except Lantana camara (undiluted) were tested through poisoned food technique and four biofungicides were also screened by dual culture method under in vitro conditions. Plant extract of Prosopis juliflora showed the maximum inhibition on the mycelial growth (81.2% over A. tenuissima and 80.0% over F. solani) and followed by L. camara (66.7% over A. tenuissima and 68.9% over F. solani). Among the antagonists Pseudomonas fluorescens and Trichoderma viride showed maximum inhibition on the mycelial growth of both pathogenic fungi. The promising plant extracts (P. juliflora and L. camara) and antagonists (P. fluorescens and T. viride) were tested against both the pathogenic fungi under in vivo conditions along with the existing popular chemical Mancozeb. All the tested plant products and bio-fungicides showed inhibitory effect on both fungi. But the maximum survival percentage of mulberry cuttings was recorded in the treatment with T. viride (95% against F. solani and 90% against A. tenuisssima) followed by P. fluorescens (90% against both fungi) and T. harzianum (80% against F. solani and 85% against A. tenuisssima). Incase of the treatments with plant extracts and chemical fungicide the P. juliflora (60% against F. solani and 55% against A. tenuisssima) showed higher survival percentage and followed by L. camara (55% against F. solani and 50% against A. tenuisssima) and Mancozeb (55% against both fungi). In case of control only 10% of survival was recorded in F. solani inoculated cuttings and 15% survival in A. tenuissima inoculated cuttings.

• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.102-107
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• 1996

Cryptococcosis is a systemic fungal infection caused by Cryptococcus neoformans. This mycosis is best known for meningeal involvement, yet, this disease rarely can be limited to the lungs. The usual portal of entry is respiratory tract. The recently rising incidence of the disease can be attributable to wide use of steroid, immunosuppressive agents and advent of AIDS. We experienced one case of pulmonary cryptococcosis in healthy person, who was admitted to the our hospital because of cough. Cryptococcus neoformans was isolated in the sputum, and lung tissue obtained by CT guide needle aspiration biopsy. Clinical improvement was noted after 6weeks of medical therapy with fluconazole.

• Tuberculosis and Respiratory Diseases
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• v.71 no.4
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• pp.278-281
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• 2011

Allergic bronchopulmonary aspergillosis (ABPA) is a complex clinical entity resulting from an allergic immune response to Aspergillus species, and most often occurs in patients with asthma. ABPA is rarely observed in the absence of asthma, which is, in fact, the principal criterion for its diagnosis. Our patient was a 53-year-old woman with no history of bronchial asthma. She presented with a 1-month history of cough, mucopurulent nasal discharge, and localized pulmonary consolidation. Peripheral blood eosinophilia and elevated serum IgE were observed. Sinus radiography showed right maxillary sinusitis. Pathologic examination of bronchoscopic biopsy specimens revealed conglomerates of fungal hyphae. Pulmonary function and bronchial provocation tests were within normal ranges. The patient was successfully treated for 3 months with itraconazole and oral prednisolone. There has been no evidence of recurrence over a 7-month follow-up. ABPA coupled with sinusitis in a nonasthmatic patient is a very rare occurrence and warrants reporting.

• Tuberculosis and Respiratory Diseases
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• v.73 no.3
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• pp.182-186
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• 2012

Cryptococcosis is an invasive fungal infection, which is more common in immunocompromised patients. However, pulmonary cryptococcosis can occur in immunocompetent patients and should be considered on a differential diagnosis for nodular or mass-like lesions in chest radiograph. Recently, we experienced a patient with pulmonary cryptococcosis, successfully treated with oral fluconazole therapy. A 74-year-old female patient was referred for an evaluation of abnormal images, a large consolidative mass with multiple nodular consolidations and small nodules that mimics primary lung cancer with multiple lung to lung metastases. Computed tomography-guided lung biopsy confirmed the diagnosis of pulmonary cryptococcosis. The follow-up image taken after 4 months with oral fluconazole treatment showed marked improvement.

• Tuberculosis and Respiratory Diseases
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• v.66 no.3
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• pp.220-224
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• 2009

Coccidioidomycosis is a fungal infection caused by the soil fungus, Coccidioides immitis, which is endemic to the south-western United States. However, the incidence of coccidioidomycosis has recently increased due to the increase in overseas travel to endemic areas. We report a case of pulmonary coccidioidomycosis diagnosed in an immunocompetent person. A 28-year-old female, who had lived in Phoenix, Arizona, USA for 2 years, was admitted for an evaluation of persistent cough with fever lasting for 2 weeks. The chest X-ray and Chest CT revealed multifocal patchy consolidation and ground-glass opacity in both lungs as well as multiple enlarged right hilar and paratracheal lymph nodes. A percutaneous needLe biopsy of the main mass-like consolidation confirmed mature spherules of Coccidioides immitis in lung tissue. Pulmonary coccidioidomycosis should be considered in patients presenting with persistent cough with fever and a history of travel to or immigration from an endemic area.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.8
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• pp.3403-3406
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• 2015

Background: Skin biopsy is the method to assist clinicians to make definite dermatological diagnosis which further helps in holistic management. Skin cancers are relatively rare clinical diagnosis in developing countries like Nepal, but the prevalence is on rise. Objectives: To investigate the profile of skin biopsies and frequencies and pattern of skin cancers in a tertiary care centre of Western Nepal. Materials and Methods: The materials consisted of 434 biopsies (1.37%) out of 31,450 OPD visits performed in the Department of Dermatology, Manipal Teaching Hospital, Pokhara, Nepal, during the period of Dec 2011-Nov 2014. Data were collected and analyzed using SPSS-16 with reference to incidence, age, sex, race and clinical and histopathological features. Results: The commonest disorders observed in biopsies were papulosquamous lesions, skin tuberculosis of different types, benign skin tumors, leprosy, collagen and fungal diseases. Viral diseases were rarely seen, probably due to straight forward clinical diagnosis. Dermatological malignancies accounted for 55/434 (12.67%) of biopsies. Skin disorders in general were commoner in females 280/434 (64%), including malignancies 32/55(58.2%). Mean age of patients with skin cancer was 54.5 years. Facilities for proper laboratory investigation of dermatological disorders will improve the quality of life. Conclusions: The most prevalent lesion in skin biopsies was papulosquamous disorders followed by skin tuberculosis of different types. Dermatological malignancy constituted 55/434 (12.67%) cases. The prevalence of skin malignancy is on rise in Nepalese society probably due to increase in life expectancy and better diagnostic services.