• Microbiology and Biotechnology Letters
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• v.31 no.4
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• pp.377-382
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• 2003

Purification of methioninase resulted in a yield of 69%, and SDS-PAGE analysis of the purified product revealed a single band of approximately 43 kDa in molecular weight. in vitro experiments with cancer cells incubated in methionine-free media demonstrated an increase in $^{11}$ C-methionine uptake to 25.8$\pm$1.1% at 6 hr, 31.8$\pm$0.8% at 24 hr, and 62.2$\pm$0.6% at 48hr, compared to controls. Treatment of the cancer cells with purified methioninase showed no decrease in survival after a 2 hr incubation with 0.01 U/ml, but survival of RR1022 cells decreased 30% after 24 to 48 hr incubation. SKOV-3 cells showed a 5% and 14% decrease in survival with 0.1 and 1 U/ml methioninase after 24 hr. After 48hr survival decreased 15% and 24% with 0.1 and 1 U/ml methioninase. Measurements of $^{11}$ C-methionine uptake in RR1022 cells demonstrated no change at 2 hr, but a 13.7$\pm$4.7% and 40.7$\pm$2.6% increase in uptake at 24 and 48 hr, respectively. SKOV-3 cells also showed no change at 2 hr, but had a 17.7$\pm$7.2% and 38.9$\pm$4.9% increase in $^{11}$ C-methionine uptake after 24 hr and 48 hr treatment with methioninase, respectively. $^{11}$ C-methionine PET imaging revealed clear visualization of both the tumors and contralateral infectious lesions. Administration of rMET appeared to result in a slight increase in tumor:nontumor contrast on $^{11}$ C-methionine PET images. Injection of purified methioninase also produced PET images where tumor uptake was higher than that of infectious lesions.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2003.09a
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• pp.82-82
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• 2003

Introduction: With the development of dose calculation algorithms for electron beams, 3D RTP systerns are available for electron beam dose distribution commercially. However, no studies evaluated the accuracy of dose calculation with ADAC Pinnacle system for electron beams. So, the accuracy of the ADAC system is investigated by comparing electron dose distributions from ADAC system against the BEAMnrc/DOSXYZnrc. Methods: A total of 33 breast cancer patients treated with 6, 9, and 12MeV electrons in our institution was selected for this study. The first part of this study is to compare the dose distributions of measurement, TPS and the BEAMnrc/DOSXYZnrc code in flat water phantom at gantry zero position and for a 10 ${\times}$ 10 $\textrm{cm}^2$ field. The second part is to evaluate the monitor unit obtained from measurement and TPS. Adding actual breast patient's irregular blocks to the first part, monitor units to deliver 100 cGy to the dose maximum (dmax) were calculated from measurement and 3D RTP system. In addition, the dose distributions using blocks were compared between TPS and the BEAMnrc/DOSXYZnrc code. Finally, the effects of tissue inhomogeneities were studied by comparing dose distributions from Pinnacle and Monte Carlo method on CT data sets. Results: The dose distributions calculated using water phantom by the TPS and the BEAMnrc/ DOSXYZnrc code agreed well with measured data within 2% of the maximum dose. The maximum differences of monitor unit between measured and Pinnacle TPS in flat water phantom at gantry zero position were 4% for 6 MeV and 2% for 9 and 12 MeV electrons. In real-patient cases, comparison of depth doses and lateral dose profiles calculated by the Pinnacle TPS, with BEAMnrc/DOSXYZnrc code has generally shown good agreement with relative difference less than +/-3%. Discussion: For comparisons of real-patient cases, the maximum differences between the TPS and BEAMnrc/DOSXYZnrc on CT data were 10%. These discrepancies were due in part to the inaccurate dose calculation of the TPS, so that it needs to be improved properly. Conclusions: On the basis of the results presented in this study, we can conclude that the ADAC Pinnacle system for electron beams is capable of giving results absolutely comparable to those of a Monte Carlo calculation.

• Korean Journal of Radiology
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• v.24 no.10
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• pp.1006-1016
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• 2023

Objective: Computed tomography (CT) is an established method for the diagnosis, staging, and treatment of multiple myeloma. Here, we investigated the potential of photon-counting detector computed tomography (PCD-CT) in terms of image quality, diagnostic confidence, and radiation dose compared with energy-integrating detector CT (EID-CT). Materials and Methods: In this prospective study, patients with known multiple myeloma underwent clinically indicated whole-body PCD-CT. The image quality of PCD-CT was assessed qualitatively by three independent radiologists for overall image quality, edge sharpness, image noise, lesion conspicuity, and diagnostic confidence using a 5-point Likert scale (5 = excellent), and quantitatively for signal homogeneity using the coefficient of variation (CV) of Hounsfield Units (HU) values and modulation transfer function (MTF) via the full width at half maximum (FWHM) in the frequency space. The results were compared with those of the current clinical standard EID-CT protocols as controls. Additionally, the radiation dose (CTDIvol) was determined. Results: We enrolled 35 patients with multiple myeloma (mean age 69.8 ± 9.1 years; 18 [51%] males). Qualitative image analysis revealed superior scores (median [interquartile range]) for PCD-CT regarding overall image quality (4.0 [4.0-5.0] vs. 4.0 [3.0-4.0]), edge sharpness (4.0 [4.0-5.0] vs. 4.0 [3.0-4.0]), image noise (4.0 [4.0-4.0] vs. 3.0 [3.0-4.0]), lesion conspicuity (4.0 [4.0-5.0] vs. 4.0 [3.0-4.0]), and diagnostic confidence (4.0 [4.0-5.0] vs. 4.0 [3.0-4.0]) compared with EID-CT (P ≤ 0.004). In quantitative image analyses, PCD-CT compared with EID-CT revealed a substantially lower FWHM (2.89 vs. 25.68 cy/pixel) and a significantly more homogeneous signal (mean CV ± standard deviation [SD], 0.99 ± 0.65 vs. 1.66 ± 0.5; P < 0.001) at a significantly lower radiation dose (mean CTDIvol ± SD, 3.33 ± 0.82 vs. 7.19 ± 3.57 mGy; P < 0.001). Conclusion: Whole-body PCD-CT provides significantly higher subjective and objective image quality at significantly reduced radiation doses than the current clinical standard EID-CT protocols, along with readily available multi-spectral data, facilitating the potential for further advanced post-processing.

• Journal of Korean Academy of Nursing Administration
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• v.16 no.2
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• pp.152-161
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• 2010

Purpose: The aim of this project was to develop a patient safety-focused inservice education program for surgical nurse and to test the effects of this program. Methods: Methodological designs for instruments development, a pretest-posttest and a posttest design were employed. After the education, nurses' satisfaction, confidence, usefulness and application of 137 nurses were evaluated at 15 surgical units of a tertiary teaching hospital in Seoul, Korea. The education contents are 6 skill areas (infusion pump use, suction, chest tube drainage, oxygen administration, nebulizer use, insulin administration) and medication knowledge. Teaching methods were lecture, instructor demonstration, and 1:1 skill test. Descriptive statistics, Wilcoxon test, Spearman's correlation and Stepwise regression were used. Results: Satisfaction scores for skills and medication education were 4.00-4.21 (out of 5), The more performance frequency in 6 skills, the higher score in confidence as well as in usefulness and application, and the higher satisfaction with the program, the higher score in usefulness, application, confidence, and medication knowledge. Medication knowledge improved after the education (Z=-7,757, p<.001). Significant predictors of skill confidence were application of skills in job performance, medication confidence, and career in present unit. Conclusion: The results of this study suggest that systematic and continuous inservice education will improve patient safety by promoting nursing quality.

• Journal of Korean Academy of Nursing
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• v.45 no.4
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• pp.523-532
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• 2015

Purpose: The usability, user satisfaction, and impact of electronic nursing record (ENR) systems were investigated. Methods: This mixed-method research was performed as a time-motion (TM) study and a survey which were carried out at six hospitals between August and November 2013. The TM study involved 108 nurses from medical, surgical, and intensive care units at each hospital, plus an additional 48 nurses who served as nonparticipating observers. In the survey, 1879 volunteer nurses completed the Impact of ENR Systems Scale, the System Usability Scale, and a global satisfaction scale. Qualitative and quantitative analyses were performed. Results: The mean scores for the ENR impact, system usability, and satisfaction were 4.28 (out of 6), 58.62 (out of 100), and 74.31 (out of 100), respectively, and they differed significantly between hospitals (F=43.43, p<.001, F=53.08 and p<.001, and F=29.13 and p<.001, respectively). A workflow fragmentation assessment revealed different patterns of ENR system use among the included hospitals. Three user characteristics-educational background, practice period, and experience of using paper records-significantly affected the system usability and satisfaction scores. Conclusion: The system quality varied widely among the ENR systems. The generally low-to-moderate levels of system usability and user satisfaction suggest many opportunities for improvement.

• Journal of Radiation Protection and Research
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• v.6 no.1
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• pp.34-40
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• 1981

The logical development of an optimum structural shielding design and the computation of protective barriers for high energy radiation therapy room, Toshiba 13 MeV. are presented. We obtained following results by comparison in between the precalculating values and actual survey after complete installation of radiogenerating units. 1. The calculating formula for the protective barrier written in NCRP report #34(1970) was the most ideal and economic calculating methods for the construction of barrier and to determine thickness for the meeting requirements of the number of patients of 80-100 in daily treatment. 2. The precalculating values of protective barrier are 5 times more protective than that of actual measurement. It is depending on radiation workload and utilization the datas most sequrely. 3. The dose rate during exposure are 2-10 mR/hr at out of the door and the controll room. 4. The foul smelling and ozone gas production from long exposure of cancer patients cannot be eliminated when the room is ill ventilated.

• Tuberculosis and Respiratory Diseases
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• v.57 no.5
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• pp.465-469
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• 2004

Exudative pleural effusion can arise from pneumonia, tuberculosis, cancer, etc. Early drainage is needed for prevention of complications such as pleural fibrosis, thickening, bronchopleural fistulae and decline of lung function. Intrapleural Instillation of fibrinolytic enzymes has been used for 50years as an adjunct in the removal of fibrous material, hematoma and pus from the thoracic cavity. By the local fibrinolytic effect on fibrinous exudates within the pleural space, fibrinolytic agent has improved results of chest tube or pig tail drainage. But there were no controlled randomized studies, so significant controversy exists concerning the efficacy of this therpy, especially tuberculous pleurisy. Furthermore about complication, severe spontaneous bleeding has not been reported with intrapleural urokinase. Intrapleural fibrinolytic enzymes has shows no systemic complication. When it is administrated intravenously, not into intrpleural space, major bleeding is reported about 1-3% of patient, especially they had systemic disease, such as coagulation abnormalities. This case report presents a patient who suffered major hemothorax induced hypovolemic shock following the administration of 100,000 units of urokinase intrapleurally. He was 25-year old male with tuberculosis pleurisy without systemic illness demonstraion.

• Molecular & Cellular Toxicology
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• v.4 no.1
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• pp.78-84
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• 2008

EGFR has been intensively investigated as a target to block the signal transduction pathway which stimulates cancer growth and metastasis. Studies about structure-activity relationship for tricyclic azepine derivatives were performed with topomer-CoMFA. The derived topomer-CoMFA model with steric and electrostatic field parameters based on fragment units gave reasonable statistics ($q^2$=0.561, $r^2$=0.679). The model explains why a halogen atom at the meta position of aniline is important to increases inhibitory activity. This comes from an electrostatically negative groups are favored near this region. The model also shows that there are sterically favored regions around methoxy group extended from oxazepine derivatives. The findings about steric and electrostatic effects can be utilized for designing new inhibitors.

• Biotechnology and Bioprocess Engineering:BBE
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• v.6 no.4
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• pp.205-212
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• 2001

One of the important characteristics of biological systems os their ability to change im-portant properties in response to small environmental signals. The molecular mechanisms that biological molecules utilize to sense and respond provide interesting models for the development of "smart" polymeric biomaterials with biomimetic properties. An important example of this is the protein coat of viruses, which contains peptide units that facilitate the trafficking of the virus into the cell via endocytosis, then out of the endosome into the cytoplasm, and from there into the nucleus, We have designed a family of synthetic polymers whose compositions have been de-signed to mimic specific peptides on viral coats that facilitate endosomal escape. Our biomimetic polymers are responsive to the lowered pH whinin endosomes, leading to distruption of the en-dosomal membrane and release of important biomolecular druges such as DNA, RNA, peptides and proteins to the cytoplasm before they are trafficked to lysosomes and degraded by lysosomal en-zymes. In this article, we review our work on the design, synthesis and action of such smart, pH-sensitive polymers.

• Clinical and Experimental Reproductive Medicine
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• v.45 no.2
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• pp.82-87
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• 2018

Objective: Concerns about the safety of assisted reproductive technology (ART) have been raised, as some studies have shown elevated incidence rates of childhood cancer, asthma, allergies, and other diseases in ART-conceived babies. Findings regarding the health of ART-conceived babies are controversial. The present study was conducted to evaluate the prooxidant-antioxidant balance (PAB) in in vitro fertilization (IVF)-conceived mice in comparison to naturally conceived offspring. Methods: Mice (6-8 weeks) were divided into two groups (IVF-conceived and naturally conceived) matched by sex, age, weight, and litter size. A 1-mL blood sample was taken and the sera were separated. The oxidant-antioxidant balance was evaluated using a fast and reliable PAB assay. The results were expressed as $mean{\pm}standard$ deviation. Results: The mean PAB values (HK units) in the IVF-conceived and naturally conceived groups were $59.70{\pm}22.30$ and $54.70{\pm}18.22$, respectively (p= 0.82). Conclusion: Since free radicals contribute to several pathological conditions and antioxidants play an important protective role against oxidative stress, evaluating the oxidant-antioxidant balance is very important. Although the results of this study showed that the quality of the defense mechanism against free radicals was not significantly different between the IVF-conceived and naturally conceived mice, other parameters of metabolic dysfunction need to be measured.