Selective detection of viable Enterococcus faecalis using propidium monoazide in combination with real-time PCR / 대한치과보존학회지

Polymerase chain reaction (PCR) can detect bacteria more rapidly than conventional plate counting. However DNA-based assays cannot distinguish between viable and dead cells due to persistence of DNA after cells have lost their vitality. Recently, propidium monoazide (PMA) treatment has been introduced. The purpose of this study is to evaluate the applicability of the PMA treatment and real-time PCR method for cell counting in comparison with plate counting and to evaluate the antibacterial efficacy of 2% CHX on E. faecalis using PMA treatment in combination with real-time PCR. Firstly, to elucidate the relationship between the proportion of viable cells and the real-time PCR signals after PMA treatment, mixtures with different ratios of viable and dead cells were used. Secondly, relative difference of viable cells using PMA treatment in combination with real-time PCR was compared with CFU by plate counting. Lastly, antibacterial efficacy of 2% CHX on E. faecalis was measured using PMA treatment in combination with real-time PCR. The results were as follows : 1. Ct value increased with decreasing proportion of viable E. faecalis. 2. There was correlation between viable cells measured by real-time PCR after PMA treatment and CFU by plate counting until Optical density (OD) value remains under 1.0. However, viable cells measured by real-time PCR after PMA treatment have decreased at 1.5 of OD value while CFU kept increasing. 3. Relative difference of viable E. faecalis decreased more after longer application of 2% CHX.

Evaluation of the influence of apical sizes on the apical sealing ability of the modified continuous wave technique / 대한치과보존학회지

This study examined the influence of the apical sizes on the sealing ability of a root canal filling. Thirty-six single rooted teeth with a single canal were divided into 3 groups (n = 12) and instrumented with either the Profile(R) or LightSpeed(R) system to achieve three different apical sizes (master apical file [MAF] of #25, #40, or #60). The teeth were filled with gutta percha using a modified continuous wave technique. The level of microleakage was determined by immersing ten teeth from each group into India ink for 1 week followed by clearing with nitric acid, ethyl-alcohol, and methylsalicylate. The microleakage was measured using vernier calipers. The data was analyzed statistically using Kruskal-Wallis one-way ANOVA and a Student-Newman-Keuls Method. Two teeth from each group were sectioned horizontally at 1, 2, 3 and 4 mm from the apex in order to observe a cross section. The apical size was significantly (p < .05) influenced the level of microleakage. In the Student-Newman-Deuls Method, MAF sizes of #25 and #40; and MAF sizes of #25 and #60, respectively showed a statistically significant difference. There was no significant difference between #40 and #60. In most cross sections, oval-shaped canals were observed, and the irregularity of the internal surface increased with decreasing apical size. There was also an increase in the area of recess, which is the area where the canal space is not filled with either gutta-percha or sealer. When the root canals are filled using a modified continuous wave technique, canal filling with more consistent and predictable outcome may be expected as the apical preparation size is increased.

Development of Mobile Nursing Information System with PDA: MobileNurseTM / 대한의료정보학회지

In this study, we developed MobileNurseTM; a prototype of mobile nursing information system using PDA. MobileNurseTM is designed to communicate with hospital information system(HIS) via mobile support station(MSS) which interchanges and stores clinical data. MobileNurseTM consists of 3 components. The first component is medical order checking module. It enables nurses to retrieve patients' information such as physicians' orders and test results at anywhere or anytime. The second component is nursing recording module which helps nurses to record the results of their practices at bedside. On the autosynchronization of MSS and PDA, the data in PDA and MSS can be interchanged and updated respectively. The last component is nursing unit care planing module. It is helpful for retrieving the nursing care plans of patients that are expected to be done, such as patients' discharge, consultation, or transfer. With use of PDA in clinical environment, nurses can spend more time on caring for patients by reducing time-consuming, redundant paperwork. It is promising that this 'point-of-care system enables nurses to improve the quality of nursing care.