General blood tests and leukocyte differential count are very useful in diagnosing, treating and managing patient’s diseases. This study was conducted to reduce errors caused by the manual method as much as possible by using an automated hematology analyzer (Sysmex K-4500), and to alleviate work burden of the laboratory. The T1 and T2 values calculated from leukocyte differential count that was obtained from the automated hematology analyzer Sysmex K-4500, and the results measured from the manual method were compared and analyzed by using the blood samples of 400 patients who were commissioned in the diagnostic laboratory of the hospital with 120 beds. Upon the results of the study, T1 and T2 obtained from lymphocyte differential count of the automated hematology analyzer Sysmex K-4500 demonstrated high correlation compared to manual method, and the analysis of monocyte, eosinophil, basophil and band cell obtained from T1, T2 and manual method enabled percentile calculation, even though it was difficult to predict the exact monocyte, eosinophil, basophil and band cell. Therefore, it is regarded that the optimal patient results can be reported if manual method observation is selectively combined while referring to T1 and T2 obtained from lymphocyte differential count of the automated hematology analyzer Sysmex K-4500.

The purpose of this study is to develop the quantitative PCR(qPCR) assay that would enable the rapid identification and simultaneous detection of six different endodontic pathogenic bacteria in a single reaction. In this study, six pairs of primers for Treponema denticola, Porphyromonas gingivalis, Fusobacterium nucleatum, Prevotella intermedia, Streptococcus mutans, and Staphylococcus aureus and two pairs of housekeeping genes were designed for a multiplex qPCR based on the SYBR Green method. The genomic DNA was extracted from reference strains and submitted to the qPCR reaction. The specificity of the amplified products was analyzed by melting curves. As a result, six distinct melting peaks were identified by the melting curve analysis and all of the target species were simultaneously discriminated. Therefore, the multiplex qPCR assay developed in this study can be used for rapid identification and detection of T. denticola, P. gingivalis, F. nucleatum, P. intermedia, S. mutans, and S. aureus at the same time. In combination with the melting curve analysis, the level of the target species and total bacterial load can be obtained.

S. aureus is reported as a major cause of nosocomial infections after dental care and involved in endocarditis, bacteremia, osteomyelitis, peritonitis, and soft tissues etc. It is very important to identify the distribution and the diversity of toxin gene associated with the S. aureus expression in dental care patients with periodontitis directly for an effective prevention and treatment of dental diseases. Fifty four strains of S. aureus were isolated from the saliva of 129 patients who were diagnosed with periodontitis at dental clinics and hospitals located in Seoul. The distribution of the virulence gene and the genetic diversity of the strains were studied using the polymerase chain reaction with isolated strains. The enterotoxin test showed Seb was the most frequent gene with 88.9%. The hemolysin gene of Hla, Hib and Hld were the most frequently gene with 98.1% (53 strains), leukocidins gene of lukM showed 90.7% (49 strains), and laminin binding protein gene of Eno showed 100% (54 strains), respectively. The diversity of the enterotoxin gen was held as Seb-Seg-Sei gene of 35.2% (19 strains), the diversity of hemolysin gene of Hla-Hlb-Hld gene was 98.1% (53 strains) and the diversity of leukocidins gene of LukD-LukM were 88.9% (48 strains), respectively. Patients with dental disease showed somehow high toxin gene expression so that S. aureus in dental care area is judged to show very highly pathogen with a high and infection rate. In the future, additional studies for these toxin genes seem to be required.