• Science of Emotion and Sensibility
• /
• v.13 no.1
• /
• pp.121-128
• /
• 2010

This study is to analyze change of connectivity between brain positions caused by relaxation through EEG coherence. EEG spectrum analysis method has been used to analyze brain activity when relaxation was experienced. However, the spectrum analysis method has a limit that could not observe interactive reaction between brain-functional positions. Therefore, coherence between positions was analyzed to observe connectivity between the measurement positions in this study. Through the method, the reaction of the central nervous system caused by the emotion change was observed. Twenty-four undergraduates of both genders(12 males and 12 females) were asked to close their eyes and listen to the sound. During experiment, EEG was measured at eight positions. The eight positions were F3, F4, T3, T4, P3, P4, O1, and O2 in accordance with International 10-20 system. The sounds with white noise and without were used for relaxation experience. Subjective emotion was measured to verify whether or not they felt relaxation. Subjective emotion of participants were analyzed by ANOVA method(Analysis of Variance). In the result, it was proved that relaxation was subjectively evoked when participants heard sound. Accordingly, it was proved that relaxation could be enhanced by the mixed white noise. EEG coherence between the measurement positions was analyzed. T-test was performed to find its significant difference between relaxation and not-relaxation. In the results of EEG coherence, connectivity with occipital lobes has been increased with relaxation, and connectivity with parietal lobes has been increased with non-relaxed state. Therefore, brain connectivity has shown different pattern between relaxed emotion and non-relaxed emotion.

• Journal of radiological science and technology
• /
• v.33 no.3
• /
• pp.277-282
• /
• 2010

The study is to verify non-uniform dose distribution in Field-In-Field (FIF) technique using two-dimensional ionization chamber (MatriXX, Wellhofer Dosimetrie, Germany) for breast tangential irradiation. The MatriXX and an inverse planning system (Eclipse, ver 6.5, Varian, Palo Alto, USA) were used. Hybrid plans were made from the original twenty patients plans. To verify the non-uniform dose distribution in FIF technique, each portal prescribed doses (90 cGy) was delivered to the MatriXX. The measured doses on the MatriXX were compared to the planned doses. The quantitative analyses were done with a commercial analyzing tool (OmniPro IMRT, ver. 1.4, Wellhofer Dosimetrie, Germany). The delivered doses at the normalization points were different to average 1.6% between the calculated and the measured. In analysis of line profiles, there were some differences of 1.3-5.5% (Avg: 2.4%), 0.9-3.9% (Avg: 2.5%) in longitudinal and transverse planes respectively. For the gamma index (criteria: 3 mm, 3%) analyses, there were shown that 90.23-99.69% (avg: 95.11%, std: 2.81) for acceptable range ($\gamma$-index $\geq$ 1) through the twenty patients cases. In conclusion, through our study, we have confirmed the availability of the FIF technique by comparing the calculated with the measured using MatriXX. In the future, various clinical applications of the FIF techniques would be good trials for better treatment results.

• Journal of radiological science and technology
• /
• v.33 no.3
• /
• pp.213-221
• /
• 2010

The Purpose of this study was to determine the effective dose to an average patient from Coronary Angiography (CA) and Percutaneous Coronary Intervention (PCI). And to estimate the lifetime attributable risk (LAR) of cancer associated with radiation exposure from CA and PCI. The dose-area product (DAP) values to the patient were recorded from 60 CA and 58 PCI. A Monte Carlo based program PCXMC was used to calculate the effective dose from DAP values for each patient. Lifetime attributable risks were estimated with models developed in the National Academies' Biological Effects of Ionizing Radiation VII report. The mean DAP values was $53.76\;Gy{\cdot}cm^2$ for CA and $165.82\;Gy{\cdot}cm^2$ for PCI. Mean effective dose were 1.28 mSv in CA, 3.94 mSv in PCI. Results of Calculate organ dose, lung doses was 2.17 mSv in CA and 6.71 mSv in PCI. Female breast doses was 5.45 mSv in CA and 16.82 mSv in PCI. LAR estimates for CA varied from 1 in 1,508 for man to 1 in 1,357 for women. In PCI procedure varied from 1 in 553 for man to 1 in 482 for women. DAP can be used as the dose indicator to calculate the organ dose and effective dose of patient based on Monte Carlo simulation. These dose estimates derived from our simulation models suggest that CA and PCI are associated with a nonnegligible LAR of cancer. This risk varies markedly and is considerably greater for women, PCI than for man, CA.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.14 no.1
• /
• pp.138-142
• /
• 2010

Purpose: PTH (parathyroid hormone) level is a useful index for prediction of hypocalcemia after thyroidectomy. The fast results are required for an early diagnosis of hypocalcemia. In this study, we evaluated the PTH change according to incubation time, and investigated the usefulness of hypocalcemia diagnosis of PTH results in early incubation time. Materials and Methods: The subjects were 131 patients who had taken the PTH test from July to August in 2009. All experiments were used IRMA method. PTH value were evaluated with the correlation between precision (10 times repeat) and recovery rate and at 0.5, 3, 6 and $18{\pm}2$ (below overnight) hours following incubation time. Data analysis was investigated with relationship of the sensitivity, specificity, PPV (positive predictive value) and accuracy. Results: The correlation was time-dependent with levels reaching $R^2$=0.987 at 0.5 hours, $R^2$=0.993 at 3 hours and $R^2$=0.996 at 6 hours compare to overnight levels. The precision (%CV${\pm}$SD) were $15.92{\pm}15.54$ at 0.5 hours, $6.91{\pm}7.38$ at 3 hours, $4.30{\pm}4.69$ at 6 hours and $4.59{\pm}2.59$ at overnight. The recovery rate (%Mean${\pm}$SD) were $96.8{\pm}5.44$ at 0.5 hours, $102.6{\pm}4.35$ at 3 hours, $100.7{\pm}2.56$ at 6 hours and $102.2{\pm}5.98$ at overnight. When 15 pg/ml of overnight density was set up as criteria, we measured the sensitivity, specificity and PPV, accuracy at 0.5, 3, 6 hours. The sensitivity was shown to 97.5% at all times. The specificity was 96.0% at 0.5 hours, 100% at 3 hours and 92.3% at 6 hours for control, respectively. The PPV was 86.6% at 0.5 hours, 100% at 3 hours and 92.8% at 6 hours. The accuracy was shown to 84.7% at 0.5 hours, 97.5% at 3 hours and 90.6% at 6 hours. These data were accompanied by a corresponding PTH value of overnight incubation time, which significantly correlated with early time results. Conclusion: The values of PTH at 3 hours has favorable the rate of concordance of 94.1% and may be useful for prediction of hypocalcemia, and it responses to overnight incubation PTH values. Therefore, This method may be an attractive alternative to proper treatment to stop symptom revelation by giving a calcium agent to the patient.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.14 no.1
• /
• pp.28-34
• /
• 2010

Purpose: According to increment of thyroid cancer recently, patients of high dose radioiodine therapy were accumulated. Taking into consideration the acceptance capability in the current facility, this study is to calculate the maximum value of high dose radioiodine therapy in patients for treatment. Materials and Methods: The amount and radioactivity of waste water discharged from high dose radioiodine therapy in patients admitted at present hospital as well as the radiation density of the air released into the atmosphere from the high dose radioiodine therapy ward were measured. When the calculated waste water's radiation and its density in the released air satisfies the standard (management standard for discharge into water supply 30 Bq/L, management standard for release into air 3 $Bq/m^3$) set by the Ministry of Education, Science and Technology, the maximum value of treatable high dose radioiodine therapy in patients was calculated. Results: When we calculated in a conservative view, the average density of radiation of waste water discharged from treating high dose radioiodine therapy one patient was 8 MBq/L and after 117 days of diminution in the water-purifier tank, it was 29.5 Bq/L. Also, the average density of radiation of waste water discharged from treating high dose radioiodine therapy two patients was 16 MBq/L and after 70 days of diminution in the water-purifier tank, it was 29.7 Bq/L. Under the same conditions, the density of radiation released into air through RI Ventilation Filter from the radioiodine therapy ward was 0.38 $Bq/m^3$. Conclusion: The maximum value of high dose radioiodine therapy in patients that can be treated within the acceptance capability was calculated and applied to the current facility, and if double rooms are managed by improving the ward structure, it would be possible to reduce the accumulated treatment waiting period for radioiodine therapy in patients.

• The Korean Journal of Nuclear Medicine Technology
• /
• v.14 no.1
• /
• pp.3-7
• /
• 2010

Purpose: The usefulness of Positron Emission Tomography (PET) images in diagnosis, staging, recurrent and treatment response evaluation has already been known. However, tumors which are small size, located in lower lobe of lung or upper lobe of liver are shown misalignment, distortion and different Standard Uptake Value (SUV) by respiration in PET images. Therefore, if radiotherapy based on normal respiration, it may cause low treatment response or more side effects because targets which had to treat, out of treat range or over dose to normal tissue. The purpose of this study is to evaluate attenuation-correction with Average CT (ACT) for more accuracy SUV measurement and minimize artifact by respiration. Materials and Methods: 13 patients, who had tumors which are around the diaphragm, underwent ACT scan after Helical CT (HCT) scan with PET/CT (Discovery DSTE 8; GE Healthcare). We quantified the differences between attenuation corrected image with HCT and attenuation corrected image with ACT in artifact size and maximum SUV ($SUV_{max}$). Artifacts were evaluated by measurement of the curved photogenic area in the lower thorax of the PET images for all patients. $SUV_{max}$ was measured separately at the primary tumors. Analysis program was Advantage Workstation v4.3 (GE Healthcare). Patients were injected with 7.4 MBq (0.2 $mC_i$) per kg of $^{18}F$-FDG and scanned 1 hour after injection. The PET acquisition was 3 minute per bed. Results: Significantly lower artifact were observed in PET/ACT images than in PET/HCT images (below-thoracic artifacts caused by under corrected $1.5{\pm}3.5$ cm vs. $13.4{\pm}4.2$ cm). Significantly higher $SUV_{max}$ were noted in PET/ACT images than in PET/HCT images in the primary tumor. Compared with PET/HCT images, $SUV_{max}$ in PET/ACT images were higher by $5.3{\pm}3.9%$ (mean value) tumor. The highest difference was observed in Lower lobe of lung (7.7 to 8.7; 13%). Conclusion: Due to its significantly reduced artifacts in lower thoracic, attenuation corrected image with ACT images provided more reliable $SUV_{max}$ and may be helpful in monitoring treatment response. Moreover, ACT can separate upper lobe of liver and lower lobe of lung, it may be helpful in interpretation. ACT will be clinically useful, considering increased dose caused by ACT scan and adapt.

• Pediatric Infection and Vaccine
• /
• v.17 no.1
• /
• pp.1-8
• /
• 2010

Purpose : Recently, vancomycin-resistant enterococci (VRE) have become one of the major nosocomial pathogens in Korea. However, there have been few studies on the epidemiology of VRE colonization among neonates. In this study, we investigated the prevalence of VRE colonization, risk factors for VRE, and how to control the spread of VRE infection in the Neonatal Intensive Care Unit (NICU) of Pusan National University Hospital (PNUH). Methods : We retrospectively reviewed medical records of 192 neonates who were admitted to the NICU of PNUH from March 2006 to March 2007. Surveillance cultures from rectal swabs for detecting VRE were obtained weekly during the study period. We analyzed the prevalence of VRE and various risk factors. Results : The rate of VRE colonization among NICU patients was 25% (48/192). Thirty five of these VRE colonized patients were transferred to the NICU from other local hospitals. Compared with the non-VRE group, the risk factors associated with VRE colonization were lower birth weight, congenital heart disease, applied mechanical ventilation, use of a central venous catheter, chest tubing, a history of surgery, and use of antibiotics. Conclusion : VRE colonization among patients admitted to the NICU is rapidly increasing. Monitoring and managing premature neonates from the beginning of the birth process, avoiding many invasive procedures, avoiding antibiotics such as vancomycin and third generation cephalosporin are important for preventing the emergence and spread of VRE colonization in the NICU.

• Korean Journal of Veterinary Research
• /
• v.50 no.3
• /
• pp.213-220
• /
• 2010

Salmonella (S.) Enterica infection ranks among the most common food borne bacterial infections worldwide. Although there are six subspecies of S. Enterica, the vast majority of human and animal infections are caused by strains belonging to subspecies 1 serovar Typhimurium and Enteritidis. Recent reports on antibiotic resistance of Salmonella spp. are rising steadily. The increasing problem of antibiotic resistance has rekindled interest in bacteriophage to therapy. Therefore, we investigated the efficacy of bacteriophage in S. enterica serovar Enteritidis infected mice and pigs by measuring of body condition, body weight, bacterial colonization and weight of organs based on the in vitro analysis. In vitro experiment, phage cultured with S. Enteritidis showed clear lysis pattern, the plaque forming unit (PFU) of our phage culture was $1.5{\times}10^{11}PFU/mL$, and phage showed its maximum activity at 4 h post inoculation. In mouse experiment, there was no significant difference among experimental groups in the general body conditions and body weight of mice. However, there was difference in weight of liver and spleen depending on the experimental group (p < 0.05). The weight of liver and spleen were reduced by the phage treatment. Also bacterial colonization in spleen and liver were significantly reduced by the phage treatment. In pig experiment, the general body conditions and body temperature exhibited not much difference among the pigs except few pigs in group 3 which showed poor body conditions. From the feces in each group, we could isolate the S. Enteritidis only from group 3. Bacterial enrichment culture was necessary for isolating the bacteria from 5 dpi and 10 dpi, however direct isolation was possible from 15 dpi feces. In phage treated group, postmortem lesion was better than non-phage treated group. Recently, antibiotic resistance concerns on the food-borne bacterial pathogens have been increasing because of the wide spread of the antibiotics resistance genes. This concern is widely transmitted to the human related public health. As one of the alternative treatments on the bacterial pathogens, attempt using phages have been made to control the bacterial diseases. The positive possibility of the trail using phage was observed to control the S. enterica serovar Enteritidis in this study even though the further analysis has been remained.

• Korean Journal of Ichthyology
• /
• v.22 no.3
• /
• pp.147-153
• /
• 2010

A study was carried out to examine the effect of water temperature on daily pattern and rate of total ammonia nitrogen (TAN) excretion in juvenile Pacific cod Gadus macrocephalus (mean body weight: $36.5{\pm}0.8\;g$) under fasting and feeding conditions. Fish were acclimated over 10 days under three different water temperatures (9, 11 and $13^{\circ}C$), and transferred to TAN measuring system under each water-temperature condition. After 72 hours of starving, fasting TAN excretion was measured at each temperature. To investigate post-prandial TAN excretion, fish were hand-fed with a commercial diet containing 40.6% crude protein for 7 days, two times daily at 08:00 and 16:00 h. Water was sampled from both the inlet and outlet of the fish chamber every 2 h over a 24-h period. Both fasting and post-prandial TAN excretion increased with increased water temperatures (p<0.05). Mean fasting TAN excretion rates at 9, 11 and $13^{\circ}C$ were 9.3, 11.0 and $11.9\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$, respectively. The value of $9^{\circ}C$ was lower than those of 11 and $13^{\circ}C$ (p<0.05), but there was no significant difference between $11^{\circ}C$ and $13^{\circ}C$. Mean post-prandial TAN excretion rates at 9, 11 and $13^{\circ}C$ were 23.0, 31.6 and $45.4\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$, respectively. A peak value of post-prandial TAN excretion rate occurred after 2 h from each feeding, and the second value is always higher than the first value. Maximum post-prandial TAN excretion rate occurred after 10 h from the first feeding at $9^{\circ}C$ (mean $38.0\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$), $11^{\circ}C$ ($52.9\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$) and $13^{\circ}C$ ($77.5\;mg\;TAN\;kg\;fish^{-1}\;h^{-1}$), respectively. The TAN loss for ingested nitrogen at $9^{\circ}C$ (43.9%) was lower than those of $11^{\circ}C$ (46.4%) and $13^{\circ}C$ (48.4%). The overall results indicate that water temperature exhibits a significant effect on the nitrogen excretion of juvenile Pacific cod.

• Journal of Environmental Health Sciences
• /
• v.38 no.6
• /
• pp.493-502
• /
• 2012

Objectives: The purpose of this study is to investigate the mass concentration of nanoparticles and understand the characteristics of elements of heavy metal concentrations within nanoparticles in the air using Micro-Orifice Uniform Deposit Impactor Model-110 (MOUDI-110), based on indoor and outdoor air. Methods: This Study sampled nanoparticles using MOUDI-110 indoors (office) and outdoors at S University in Asan, Korea in order to reveal the concentration of nanoparticles in the air. Sampling continued for nine months (10 times indoors and 14 times outdoors) from March to November 2010. Mass concentrations of nanoparticle and concentrations of heavy metals (Al, Mn, Zn, Ni, Cu, Cr, Pb) were analyzed. Results: Indoors, geometric mean concentration of nanoparticles ranged in size from 0.056 ${\mu}m$ to 0.10 ${\mu}m$ and those of 0.056 ${\mu}m$ or less recorded 0.929 ${\mu}g/m^3$ and 1.002 ${\mu}g/m^3$, respectively. On the other hand, the levels were lower outdoors with 0.819 ${\mu}g/m^3$ and 0.597 ${\mu}g/m^3$. Mann-Whitney U tests showed that the difference between the indoors and the outdoors was statistically meaningful in terms of particles of 0.056 ${\mu}m$ or less (p<0.05) in size. These results are possibly influenced by the use of printers and duplicators as the factor that increased the concentration of nanoparticles. In seasonal concentration distribution, the level was higher during the summer compared to in the autumn. Those of 0.056 ${\mu}m$ or less in size presented a statistically meaningful difference during the summer (p<0.05). These results may be influenced by photochemical event as the factor that makes the levels high. Regarding zinc, among the other heavy metals, the fine particles ranged in size from 0.056 ${\mu}m$ to 0.10 ${\mu}m$ and those of 0.056 ${\mu}m$ or less recorded 1.699 $ng/m^3$ and 1.189 $ng/m^3$ in the outdoors. In the indoors, the levels were lower, with 0.745 $ng/m^3$ and 0.617 $ng/m^3$. Cr and Ni at the size of 0.056 ${\mu}m$ or less, both of which have been known to pose severe health effects, recorded higher concentrations indoors with 0.736 $ng/m^3$ and 0.177 $ng/m^3$, compared to 0.444 $ng/m^3$ and 0.091 $ng/m^3$ outdoors. By season, Zn, Ni, Cu and Pb posted a high level of indoor concentration during the fall. As for Cr, the level of concentration indoors was higher than outdoors both during the summer and the autumn. Conclusion: This study indicates the result of an examination of nano-sized particles and heavy metal concentrations. It will provide useful data for the determination of basic nanoparticle standards in the future.