• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.265-274
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• 1998

This study was carried out to obtain the basic data for an artificial cultivation of Phellinus sp.. The optimum conditions for the mycelial growth on the different sawdusts (Quercus aliena, Morns alba and Alnus japonica) substrate of an isolated Phellinus sp. were optimized by response surface methodology. The ratio of rice bran addition to sawdust and the suitable moisture content for the mycelial growth in the all sawdust media were about 30% (w/w) and $65{\sim}70%$ (w/v), respectively. The initial pHs for the mycelial growth of Quercus aliena and Morns alba were in the range of $pH\;5{\sim}6$, whereas Alnus japonica was obtained at pH 6. The optimum temperature for the mycelial growth was about $25{\sim}30^{\circ}C$, depending on the different kinds of wood substrates. From the response surface analysis, the values of independent variables of Quercus aliena at stationary points were determined to be 31.01 % (w/w) of rice bran, pH of 5.31 and 69.03% (w/v) of moisture content, and the expected value of mycelial growth was about 8.32 cm. Both the ratio of rice bran addition to sawdust $(X_1)$ and moisture content $(X_3)$ were effective to the mycelial growth. In the case of Morns alba, the ratio of rice bran addition to sawdust, initial pH and moisture content at the stationary points were 28.77% (w/w), 5.28 and 69.8 (w/v),respectively, and the expected mycelial growth of 7.60 cm was obtained. Stationary points for the mycelial growth in the sawdust media of Alnus japonica were 28.74% (w/w) of rice bran, pH of 6. 04 and 66.96% (w/v) of moisture content, and the expected values of mycelial growth was about 5.38 cm. Based on the above results, there was correlations between the mycelial growth and independent variables, and the effect of rice bran $(X_1)$ and initial pH $(X_2)$ for the mycelial growth were higher than the moisture content $(X_3)$. The optimum species of sawdust media for the my celial growth of Phellinus sp. was in the order of Quercus aliena > Morns alba > Alnus japonica.

• The Korean Journal of Mycology
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• v.25 no.4 s.83
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• pp.311-319
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• 1997

These studies were carried out to develop an artificial cultivation method. The diameter and thickness of pileus ranged $1.5{\sim}7.0\;cm$ and $0.8{\sim}3.0\;cm$, respectively. The diameters of stipe were $1.2{\sim}2.5\;cm$ and the lengthes were $4.5{\sim}9.0\;cm$. The spore fingerprint was white. The sizes were spore $10.8{\sim}12.2{\times}4.35{\sim}5.65\;{\mu}m$, basidia $50.0{\sim}59.2{\times}7.4{\sim}7.8\;{\mu}m$, nalsistidia $21.75{\sim}28.7{\times}4.8{\sim}6.1\;{\mu}m$, pileus hymenium cell $50.6{\sim}66.0{\times}4.4{\sim}6.7\;{\mu}m$, and stipe hymenium cell $28.6{\sim}33.0{\times}5.5{\sim}6.6\;{\mu}m$. The thirty percent mixture of rice and wheat bran into sawdust gives the high density of mycelia and the good development of fruiting structure. The optimum water contents of sawdust substrates were $60{\sim}65%$ in which condition the mycelium grows well and gives high density. In PP bottle cultivation, the first fruiting period was $6{\sim}8$ days earlier in nonscratching samples than scratching ones, but the quantity of fruiting body was higher in scratching samples than nonscratching ones. In the case of PP bag cultivation, the first fruiting was 10 days faster, and the quantity of fruiting bodies was 30% higher in samples with 30% wheat bran than those with rice bran. The fleshiness of stipe was $2{\sim}3$ times harder than that of pileus.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.105-110
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• 1984

Seven seed samples of corn obtained from Kangweon Provincial Office of Rural Development, Kerea were tested for seed-borne fungi, and found that all the samples tested were infected with Fusarium moniliforme to an extent of $6.0{\sim}79.5%$. Severely infected seed samples showed poor germination on blotter. Seed component plating showed that the fungus present not only in tip caps, pericarps and endosperms, but also in embryos. Heavy infection of the fungus caused severe seed rot and seedling blight in soil, but the damage was not severe and many plants grew without any symptoms when the seeds with light infection were sown in soil. However the fungus was frequently detected from inside of the stems of healthy looking seedlings. The results indicate that the fungus transmit from seed to plant systemically. In inoculation experiments, the fungus produced stem rots on corn plants of 110 days old. The cultivar of Hwangok 3 was revealed more susceptible to the fungus than that of Suweon 19.

• Tuberculosis and Respiratory Diseases
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• v.43 no.1
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• pp.30-37
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• 1996

Background: The extraction methods of DNA from clinical samples are the major obstacle to use the PCR(polymerase Chain Reaction) in routine labortary for early detection of M. tuberculosis. We tried to improve the extraction method of DNA from sputum for establishment of the PCR in routine labortary by reducing the possibility of cross contamination and performing it easily and safely. Methods: We used the $InstaGene^{TM}$ DNA extraction kit(BioRad Co.) using Chelex 100 ion exchange resin for preparation of DNA. We compared InstaGene method in 100 cases of sputum from proteinase K method which is known as the most commonly used method for DNA purification(Experiment 1). And we compared InstaGene method in 98 cases of sputum from Microwave method developed by a company in Korea(Experiment 2). In experiment 1,245bps of IS6110 were amplified and then 188bps were amplified by nested PCR. In experiment 2,536bps in primary PCR and 276bps in nested PCR were amplified and analysed by agarose gel electrophoresis and EtBr staining. Results: When we chose AFB smear, culture, or AFB smear and culture as a standard test, PCR had low specificity and positive predictive value in both experiments. The InstaGene method has higher value in sensitivity and negative predictive value significantly than proteinase K method. The InstaGene method and the Microwave methods were similar in sensitivity, specificity, positive predictive value and negative predictive value. Conclusion: Even though both methods had lower possibility of cross contamination, shorter time requirement, simplicity, and economic advantages than Proteinase K method, the InstaGene method was a little simpler than the Microwave method. Therefore, in terms of usefulness in clinical application, the Instagene method seems to be the most useful method in DNA extraction for detection of M. tuberculosis using PCR. The reliability of this method will be clarified by further studies with enough clinical samples.

• Tuberculosis and Respiratory Diseases
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• v.57 no.2
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• pp.138-142
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• 2004

Background : To evaluate exudative pleural fluid, thoracentesis for microbiological and cytological examination and pleural biopsy by using a Cope needle are traditionally performed. Even after these studies, about 20% of patients remain undiagnosed. We evaluated the diagnostic accuracy and complications of 2-mm minithoracoscopy instead of blind biopsy in patients with undiagnosed exudative pleural effusion. Method : Fifteen patients with exudative pleural effusion underwent thoracoscopy between April 2002 and August 2003. The indication was undiagnosed pleural effusions after having performed sputum and pleural fluid exami-nations both microbiologically and cytologically. Results : The median age of the patients was 56 years (range 21-77). Pleural effusions were lymphocyte-dominant in 11 patients (73.3%) and neutrophil-dominant in 3 (20.0%). The remaining patient (6.7%) had pleural-fluid eosinophilia. Minithoracoscopic biopsy revealed accurate diagnosis in 14 patients (93.3%), consisting of tuberculous pleurisy in 8 (66.7%), malignant effusions in 4 (33.3%), and parapneumonic effusions in 2 (13.3%). One was diagnosed as having paragonimiasis from thoracoscopic findings and clinical considerations. There was no procedure-associated mortality. There were six cases of new onset fever (40%) and one of pneumothorax (6.7 %). Conclusion : Two-millimeter minithoracoscopy, which is less invasive than conventional thoracoscopy, was an accurate and safe method for undiagnosed exudative pleural effusion.

• Tuberculosis and Respiratory Diseases
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• v.59 no.6
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• pp.606-612
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• 2005

Background : It has been reported that nontuberculosis mycobacterium(NTM) isolates account for approximately 10% of patients with a positive Acid-Fast Bacilli(AFB) smear. Therefore, it is necessary to consider NTM pulmonary disease when such a positive test is encountered. The aim of this study was to evaluate the etiologies and clinical characteristics of patients with NTM pulmonary disease who had been treated at a national tuberculosis hospital. Methods : The NTM isolates were recovered from the sputum or bronchial washing specimens submitted to a clinical laboratory of National Masan TB Hospital from August 2002 to July 2003. All samples were identified using a polymerase chain reaction-restriction fragment length polymorphism analysis method, which amplifies the rpoB gene. The patients were diagnosed with NTM disease according to the American Thoracic Society diagnostic criteria. Results : One hundred NTM isolates were recovered from 57 patients. Of the 100 isolates, M. avium complex(MAC) was the most common species, which was found 55%(n=55) of patients, followed by M. abscessus(n=25), and M. fortuitum( n=9). 26(45.6%) patients had NTM disease. Twenty-six (45.6%) patients had NTM disease according to The American Thoracic Society classification. The main organisms involved in NTM disease were MAC(n=19, 73.1%) and M. abscessus(n=5, 19.2%). The pathogenic potential was 67.9% in M. intracellulare and 41.7% in M. abscessus. The predictive factors related to NTM disease were a positive sputum smear (OR 6.4, p=0.02) and the isolation of either MAC or M. abscessus(OR 6.9, p=0.007). Fifteen patients(57.7%) were cured. There were no significant factors associated with the treatment success. Conclusion : There was a relatively high proportion of NTM disease in NTM isolates and the common species were MAC and M. abscessus. The predictive factors for NTM disease were a positive sputum smear and the isolation of either MAC or M. abscessus.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.1041-1048
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• 2016

Biofilm cells and viable but non-culturable (VBNC) state may play a role in the survival of Campylobacter jejuni under unfavorable environmental conditions. The objective of this study was to investigate the behavior of C. jejuni biofilm cells and VBNC cells on smoked duck. The transfer of C. jejuni biofilm cells to smoked duck and its ability to resuscitate from biofilm and VBNC cells on smoked duck was investigated. Transfer experiments were conducted from C. jejuni biofilm cells to smoked duck after 5 min, 1 h, 3 h, and 24 h contact at room temperature, and the efficiency of transfer (EOT) was calculated. In addition, smoked duck was inoculated with C. jejuni biofilm and VBNC cells and then stored at 10, 24, 36, and $42^{\circ}C$ to examine the cells' ability to resuscitate on smoked ducks. The 5 min contact time between C. jejuni biofilm cells and smoked duck showed a higher EOT (0.92) than the 24 h contact time (EOT=0.08), and the EOT decreased as contact time increased. Furthermore, C. jejuni biofilm cells on smoked duck were not recovered at 10, 24, and $36^{\circ}C$, and C. jejuni VBNC cells were not resuscitated at $42^{\circ}C$. Although the resuscitation of C. jejuni biofilm and VBNC cells was not observed on smoked duck, microbial criteria of C. jejuni is needed in poultry and processed poultry products due to risk of its survival and low infectious dose.

• KSBB Journal
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• v.24 no.1
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• pp.30-40
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• 2009

Statistical optimization of the production medium was carried out in order to find an optimal medium composition in itaconic acid fermentation process. Itaconic acid utilized in the manufacture of various synthetic resins is a dicarboxylic acid biosynthesized by fungal cells of Aspergillus terreus in a branch of the TCA cycle via decarboxylation of cis-aconitate. Through OFAT (one factor at a time) experiments, six components (glucose, fructose, sucrose, soluble starch, soybean meal and cottonseed flour) were found to have significant effects on itaconic production among various carbon- and nitrogen-sources. Hence, using these six factors, interactive effects were investigated via fractional factorial design, showing that the initial concentrations of sucrose and cottonseed flour should be high for enhanced production of itaconic acid. Furthermore, through full factorial design (FFD) experiments, negative effects of $KH_2PO_4$ and $MgSO_4$ on itaconic acid biosynthesis were demonstrated, when excess amounts of the each component were initially added. Based on the FFD analysis, further statistical experiments were conducted along the steepest ascent path, followed by response surface method (RSM) in order to obtain optimal concentrations of the constituent nutrients. As a result, optimized concentrations of sucrose and cottonseed flour were found to be 90.4g/L and 53.8g/L respectively, with the corresponding production level of itaconic acid to be 4.36 g/L (about 7 fold higher productivity as compared to the previous production medium). From these experimental results, it was assumed that optimum ratio of the constituent carbon (sucrose) and nitrogen (cottonseed flour) sources was one of the most important factors for the enhanced production of itaconic acid.

• Tuberculosis and Respiratory Diseases
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• v.60 no.3
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• pp.285-289
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• 2006

Background : North Korea's economic and public health problems began in the early 1990s as a result of the gradual loss of economic support from its communist allies, combined with an inordinate number of natural disasters. The decline in public health has increased the incidence of tuberculosis in North Koreans and refugees. This study investigated tuberculosis situation in North Korean refugees in order to prepare for the future impact of tuberculosis control in Korea. Material and Methods : From 2001 to 2005, tuberculosis patients among North Korean refugees who were diagnosed before or after arriving in South Korea, based on the official records of OO hospital, were enrolled in this study. The demographic and clinical data of the cases were evaluated retrospectively. Results : A total of 42 TB cases were reviewed during the study period. Of these, 37 (88.1%) cases were pulmonary TB. based on the cases identified among the number of North Korean refugees' arriving each year, the annual incidence of pulmonary TB were 900 per 100,000 in 2004, 700 in 2003, The number of smear-positive patients was 20 (47.6%) and the number of culture-positive patients was 18 (42.9%). Of the M. tuberculosis isolates, 2 cases were found to be susceptible to all anti-TB drugs available, 4 were resistant to isoniazid, and 3 were multi-drug resistant. Conclusion : The prevalence of pulmonary TB in North Korean Refugees is high. In addition, North Korean refugees suffer from more severe tuberculosis in bacteriological and radiological aspects.

• Tuberculosis and Respiratory Diseases
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• v.66 no.5
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• pp.358-364
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• 2009

Background: The appropriate empirical antimicrobial choice in the treatment of community-acquired pneumonia (CAP) should be advocated by community-based information on the etiologic pathogens, their susceptibility to antimicrobials, clinical characteristics and outcomes. Jeju is a geographically isolated and identical region in Korea. However, there is no regional reference on adult CAP available. This study investigated the etiologic agents and clinical outcomes of adult patients diagnosed with CAP in Jeju, Korea, to help guide the empirical antimicrobial choice. Methods: A prospective observational study for one year in a referral hospital in Jeju, Korea. Patients diagnosed with CAP were enrolled with their clinical characteristics. Microbiological evaluations to identify the etiologic agents in the adult patients with CAP were performed with blood culture, expectorated sputum smear and culture, antibody tests for mycoplasma, chlamydophila, and antigen tests for legionella and pneumococcus. The clinical outcomes of the initial empirical treatment were analyzed. Results: Two hundred and three patients with mean age of 64 and 79 females were enrolled. Ten microbials from 90 cases (44.3%) were isolated and multiple isolates were confirmed in 30. Among the microbial isolates, S. pneumoniae (36.3%) was the most common, followed by M. pneumoniae (23.0%), C. pneumoniae (17.0%), S. aureus (9.6%) and P. aeruginosa (5.9%). The initial treatment failure (23.8%) was related to the isolation of polymicrobial pathogens, elevated inflammatory markers, and the presence of pleural effusion. Among the 30 isolates of S. pneumoniae, 16 (53.3%) were not susceptible to penicillin, and 19 isolates (63.3%) to erythromycin and clarithromycin. However, 29 isolates (96.7%) were susceptible to levofloxacin and ceftriaxone. Conclusion: S. pneumoniae, M. pneumoniae, S. aureus, and P. aeruginosa are frequent etiologic agents of adult CAP in Jeju, Korea. The clinical characteristics and antibiotic resistance should be considered when determining the initial empirical antimicrobial choice. Respiratory quinolone or ceftriaxone is recommended as an empirical antimicrobiotic in the treatment of adult CAP in Jeju, Korea.