1.Studies on the Mycobacteria Isolated from Soil.
Yonsei Medical Journal 1981;22(1):1-20
Acid-fast microorganisms were isolated from 240 soil samples collected at two areas, Hiroshima, Japan and Seoul, Korea. The biological and biochemical characteristics of the isolated mycobacteria were tested and compared with those of 36 reference mycobacteria Strains. The isolation rate and distribution of these mycobacterial species from soil were compared using three kinds of media with emphasis on the two methods of isolation between the different geographical areas. One Strain from each of the 10 species among atypical mycobacteria isolated from soil in both areas was inoculated into ddY mice and the pathogenicity compared with that of Mycobacterium tuberculosis H37Rv up to 6 weeks. Susceptibility of the reisolated acid-fast bacilli to antimycobacterial agents was tested in vitro. Antibody responses against various mycobacterial antigens were tested using lepromatous type and tuberculoid type patient sera by the agar gel immunodiffusion. 1) No significant differences in the distribution of acid-fast bacilli were observed between soil samples from the two regions. 2) Rapid growers were by far the most frequent acid-fast bacilli isolated while no photochromogens were isolated from these soil samples. In addition, a minimal number of fastidious mycobacteria were isolated but not cultivable in subcultures. 3) Some of these soil acid-fast bacilli were capable of inducing only transient bacteriological and pathologic changes in mouse organs. 4) Acid-fast bacilli reisolated from organs of these infected mice were, in general, found to be resistant to antimycobacterial agents. 5) M. scrofulaceum antigen showed a precipitation reaction in agar gel immunodiffusion with the highest number of sera from leprosy patients.
Animal
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Leprosy/immunology
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Mice
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Mycobacteria, Atypical/drug effects
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Mycobacteria, Atypical/isolation & purification*
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Mycobacteria, Atypical/pathogenicity
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Mycobacterium/isolation & purification*
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Mycobacterium Infections/pathology
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Soil Microbiology*
2.Nontuberculous Mycobacterial Pulmonary Diseases in Immunocompetent Patients.
Won Jung KOH ; O Jung KWON ; Kyung Soo LEE
Korean Journal of Radiology 2002;3(3):145-157
Nontuberculous mycobacterial (NTM) infections are an increasingly recognized cause of chronic lung disease in immunocompetent adults, and the M. avium complex, M. kansasii, and a rapidly growing mycobacteria such as M. abscessus, M. fortuitum, and M. chelonae account for most of the pathogens involved. Because the clinical features of NTM disease are not distinguishable from those of tuberculosis, and NTM are ubiquitous in the environment, diagnosis requires that the bacilli are isolated and identified. NTM diseases have been difficult to treat, though since the introduction of new macrolides, the outcome for patients with some NTM diseases has improved significantly. For correct diagnosis and the successful treatment of NTM pulmonary disease, a knowledge of the full spectrum of clinical and radiological findings is important.
Adult
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Aged
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Female
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Human
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Immunocompromised Host/*immunology
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Lung Diseases/immunology/*microbiology/*radiography
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Male
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Middle Age
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Mycobacteria, Atypical/*isolation & purification
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Mycobacterium Infections, Atypical/immunology/*radiography
3.Identification of Mycobacteria Species by HPLC and Species Distribution during Five Years at Ulsan University Hospital.
Joseph JEONG ; Sung Ryul KIM ; Chulhun L CHANG ; Seon Ho LEE
The Korean Journal of Laboratory Medicine 2008;28(1):24-33
BACKGROUND: Infections caused by mycobacteria have been significantly increasing. Due to the difficulty of making a decision about the pathogenicity of mycobacteria, species-level identification is very important for patients' diagnosis and treatment. The purpose of this study was to identify mycobacteria species using a high performance liquid chromatography (HPLC) method and to provide an initial database for the distribution of mycobacteria in Korea. METHODS: Acid fast bacteria isolated from 3,107 clinical specimens were identified by mycolic acid analysis using HPLC. The HPLC patterns were compared with those of standard mycobacteria species. RESULTS: The HPLC patterns were divided into single, double, and triple cluster groups, each group comprising 9, 20, and 4 species, respectively. Mycobacteria and non-tuberculous mycobacteria (NTM) were identifies by HPLC at the rates of 99.5% and 95.6%, respectively. NTM was isolated in 12.4% of the mycobacteria positive specimens. This study also found that there were 20 different NTM species with the distribution of each species ranging from 0.3% to 15.9% of the total NTM. While the rate of NTM has been increasing in Korea, M. avium-intracellulare, M. fortuitum, and M. chelonae are relatively decreasing, and M. kansasii and M. gordonae are relatively increasing. CONCLUSIONS: HPLC method was highly discriminative for the identification of NTM in clinical specimens.
Bacterial Typing Techniques
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Chromatography, High Pressure Liquid/*methods
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Hospitals, University
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Humans
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Korea
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Mycobacteria, Atypical/chemistry/*isolation & purification
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Mycobacterium Infections, Atypical/drug therapy/microbiology
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Mycolic Acids/analysis
4.Clonal Dissemination of Extended-Spectrum beta-Lactamase (ESBL)-Producing Klebsiella pneumoniae Isolates in a Korean Hospital.
Kwan Soo KO ; Joon Sup YEOM ; Mi Young LEE ; Kyong Ran PECK ; Jae Hoon SONG
Journal of Korean Medical Science 2008;23(1):53-60
In this study, we investigated the molecular characteristics of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae isolates that were recovered from an outbreak in a Korean hospital. A new multilocus sequence typing (MLST) scheme for K. pneumoniae based on five housekeeping genes was developed and was evaluated for 43 ESBL-producing isolates from an outbreak as well as 38 surveillance isolates from Korea and also a reference strain. Overall, a total of 37 sequence types (STs) and six clonal complexes (CCs) were identified among the 82 K. pneumoniae isolates. The result of MLST analysis was concordant with that of pulsedfield gel electrophoresis. Most of the outbreak isolates belonged to a certain clone (ST2), and they produced SHV-1 and CTX-M14 enzymes, which was a different feature from that of the K. pneumoniae isolates from other Korean hospitals (ST20 and SHV-12). We also found a different distribution of CCs between ESBL-producing and -nonproducing K. pneumoniae isolates. The MLST method we developed in this study could provide unambiguous and well-resolved data for the epidemiologic study of K. pneumoniae. The outbreak isolates showed different molecular characteristics from the other K. pneumoniae isolates from other Korean hospitals.
Electrophoresis, Gel, Pulsed-Field
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Hospitals
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Humans
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Klebsiella pneumoniae/*classification/enzymology/genetics/isolation & purification
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Sequence Analysis, DNA
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beta-Lactamases/*biosynthesis
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Mycobacteria, Atypical/*drug effects/genetics/isolation & purification
5.Usefulness of Multiplex Real-Time PCR and Melting Curve Analysis in Identification of Nontuberculous Mycobacteria.
Seong Ho KANG ; Kwang Cheol YOO ; Kyoung Un PARK ; Junghan SONG ; Eui Chong KIM
The Korean Journal of Laboratory Medicine 2007;27(1):40-45
BACKGROUND: Nontuberculous mycobacteria (NTM) should be correctly identified to the species level, because of different treatment plans among NTM species. This study was performed to assess the usefulness of real-time PCR and melting curve analysis in the identification of NTM. METHODS: One hundred fifty-two clinical NTM isolates were identified to the species level by PCR-restriction fragment length polymorphism analysis (PRA). Those strains were then identified by multiplex real-time PCR and melting curve analysis on the 16S rRNA gene and hsp65 gene. RESULTS: In the 16S rRNA gene fragment analysis, M. abscessus-M. chelonae group showed melting point at temperatures above 65 degrees C and M. avium complex (MAC; M. avium and M. intracelluare) below 48 degrees C, which differentiated M. abscessus-M. chelonae group and MAC from other NTM. In the hsp65 gene fragment analysis, M. abscessus-M. chelonae group was clearly divided into M. abscessus type I, M. abscessus type II, and M. chelonae according to the melting points at 61.25 degrees C, 66.06 degrees C, and 57.58 degrees C, respectively. CONCLUSIONS: With the multiplex real-time PCR and melting curve analysis of 16S rRNA and hsp65 genes, M. abscessus and M. chelonae were readily identified and MAC were differentiated from other NTM. Especially, M. abscessus and M. chelonae, which were not differentiated from each other with the 16S rRNA gene fragment analysis, were identified with hsp65 gene fragment analysis.
Bacterial Proteins/genetics
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Chaperonins/genetics
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Computer Systems
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DNA, Bacterial/chemistry
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Mycobacteria, Atypical/genetics/*isolation & purification
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Nucleic Acid Denaturation
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Polymerase Chain Reaction/*methods
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RNA, Ribosomal, 16S/genetics