Recent Epidemic Emergence of Vibrio parahaemolyticus O3:K6 in Korea / 대한임상병리학회지

BACKGROUND: V. parahaemolyticus O3:K6 strains responsible for the increase in the number of cases of diarrhea in Southeast Asia since 1995. We performed serotyping of V. parahaemolyticus isolated from different geographic areas in Korea since 1998. METHODS: A total of 45 V. parahaemolyticus strains were isolated from clinical specimens of pa-tients with diarrhea in different geographic areas of Seoul (Hanyang University Hospital, 16 cases), Incheon (Gachon Medical Center, 27 cases) and Gwangju (Chonnam University Hospital, 2 cases) from 1998 to 2000 in Korea. Serovar O3:K6 of V. parahaemolyticus was determined by slide and tube agglutination tests with specific antisera (Seiken, Japan). RESULTS: The twenty-eight (62%) of 45 samples were positive to specific antisera of V. parahae-molyticus O3:K6. The O3:K6 strains were detected 11/16 (69%) in Seoul, 15/27 (56%) in Incheon, and 2/2 (100%) in Gwangju. V. parahaemolyticus O3:K6 was detected 11/16 (69%) in 1998, 12/18 (67%) in 1999, and 5/11 (45%) in 2000, respectively. CONCLUSIONS: We report the epidemic emergence of V. parahaemolyticus O3:K6 in Korea, since 1998.

Detection of Thermostable Direct Hemolysin Gene and Thermostable Direct Hemolysin-Related Hemolysin Gene of Vibrio parahaemolyticus by Polymerase Chain Reaction / 대한임상병리학회지

BACKGROUND: Vibrio parahaemolyticus is one of the most important food-borne pathogens in Korea. Although the mechanism of its pathologic effect is still not clearly understood, epidemiological studies have suggested a very strong association of thermostable direct hemolysin (TDH) and thermostable direct hemolysin-related hemolysin (TRH) with the disease. We detected the tdh gene and the trh gene of V. parahaemolyticus isolates by polymerase chain reaction (PCR). METHODS: V. parahaemolyticus strains were isolated from clinical specimens of patients with diarrhea in different geographic areas of Seoul (16 cases), Inchon (27 cases) and Kwang Joo (2 cases) in Korea between 1998 and 2000. The colonies selected were identified by using the API 20E identification strip (API system, Analytab Products, Montalieu-Vercieu, France). PCR protocols were established for specific detection of the tdh and trh genes. Oligonucleotide primers were designed based on the reported nucleotide sequence of the tdh2 gene and the trh1 gene, respectively. RESULTS: The protocols established for the tdh and trh genes could detect 400 fg (100 colony-forming units) of cellular DNA carrying the respective gene. All strains of V. parahaemolyticus isolates in this study contained the tdh gene but not the trh gene. CONCLUSIONS: The detection of the tdh gene and trh gene of V. parahaemolyticus using the PCR is an easy and rapid method.

Sequence Analysis of the omp1 gene in Chlamydia pneumoniae / 대한임상병리학회지

BACKGROUND: Chlamydia pneumoniae has recently been established as an important cause of acute respiratory tract infections such as pneumonia and bronchitis in humans. The purpose of our study was to define the sequence of the C. pneumoniae omp1 gene. METHODS: The omp1 gene of C. pneumoniae was amplified by touchdown polymerase chain reaction (PCR) on sputum samples. The PCR product was cloned into pT7Blue T-Vector using the TA cloning technique. The nucleotide sequence of the cloned omp1 gene was determined with the Cy5TM AutoReaderTM Sequencing Kit. RESULTS: We designated the cloned PCR product as CpT-207. The sequence of CpT-207 DNA was 96%-100% identical to the omp1 gene of C. pneumoniae isolated from other countries. CONCLUSIONS: The sequence analysis of CpT-207 DNA was almost identical to the sequences of the omp1 gene of C. pneumoniae isolated from other countries. The CpT-207 can be used as a control or a probe for the molecular diagnosis of C. pneumoniae.