• 한국의학물리학회지:의학물리
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• 제27권4호
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• pp.241-249
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• 2016

The present study used a digital angiography x-ray device to measure the space dose and exposure dose of patients and practitioners using x-ray tube shielding devices developed in our laboratory. The intent of the study was to reduce the space dose within the test room, and to reduce the exposure dose of patients and practitioners. The patient and practitioner exposure doses were measured in five configurations in a human body model. The glass dosimeter was placed on the eye lenses, thyroid glands, left shoulder, right shoulder, and gonads. The beam was collimated at full size and at a 48% reduction for a comparative analysis of the measurements. The space dose was measured with an ion chamber at distances of 50 cm, 100 cm, and 150 cm from the x-ray tube under the following conditions: no shielding device; a shielding device made of 3-mm-thick lead (Pb) [Pb 3 mm shield], and a shielding device made of 3-mm-thick Pb (outside) and 3-mm-thick aluminum (Al) (inside) [Pb 3 mm＋Al 3 mm shield]. The absorbed dose was the lowest when the 3-mm-thick Pb＋3-mm-thick Al shield was used. For measurements made with collimated beams with a 48% reduction, the dose was the lowest at $154{\mu}Gy$ when the 3-mm-thick Pb＋3-mm-thick Al shield was used, and was $9{\mu}Gy$ lower than the measurements made with no shielding device. If the space dose can be reduced by 20% in all situations where the C-arm is employed by using the x-ray tube shielding devices developed in our laboratory, this is expected to play an important role in reducing the annual exposure dose for patients, practitioners, and assistants.

• 한국콘텐츠학회논문지
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• 제10권5호
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• pp.343-350
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• 2010

체외충격파쇄석술(Extracorporeal shock wave lithotripsy ; ESWL) 시 환자가 받는 방사선 피폭선량을 측정하기 위하여 신장 및 요관 결석으로 진단을 받은 총 55명(남:36명, 여:19명)을 대상으로 방사선피폭선량을 측정하였다. 측정 방법은 투시 관전압 80kVp, 관전류 5mA로 고정하여 인체 모형의 Rando Phantom과 형광유리 선량계를 사용하였으며, 주요 장기인 양측 신장, 방광, 간에 5분과 10분씩 각각 2회 흡수선량을 측정하여 유효선량으로 환산하였다. 환자 당 평균 시행 횟수는 1.8회(1~4)이었고, 평균 투시시간은 533초(248~2516)로 나타났다. 우측 신장결석 치료 시 우측 신장의 평균값은 2.458mSv, 좌측 신장은 0.152mSv, 간은 1.404mSv, 방광은 0.019mSv로 측정 되었고, 좌측 신장결석 치료 시 좌측 신장의 평균값은 2.496mSv, 우측 신장은 0.252mSv, 간은 0.178mSv, 방광은 0.017mSv이었으며, 하부요관 결석치료 시 방광에서의 평균값은 3.742mSv, 우측 신장은 0.009mSv, 좌측 신장은 0.01mSv로 유효선량이 측정 되었다.

• Journal of Pharmaceutical Investigation
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• 제38권1호
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• pp.15-21
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• 2008

Liposomes as one of the efficient drug carriers have some shortcomings such as their short circulation time, fast clearance from human body by reticuloendothelial system (RES) and limited intracellular uptake to target cell. In this study, polyethylenglycol (PEG)-incorporated cationic liposomes were prepared by ionic complexation of positively charged liposomes with carboxylated polyethyleneglycol (mPEG-COOH). The cationic liposomes had approximately $98.6{\pm}1.0nm$ of mean particle diameter and $42.8{\pm}0.8mV$ of zeta potential value. The PEG-incorporated cationic liposomes had $110.1{\pm}1.2nm$ of mean particle diameter with an increase of about 10 nm compared to the cationic liposomes. Zeta potential value of them was $12.9{\pm}0.6mV$ indicating 30mV decrease of cationic charge compared to the cationic liposomes. The amount of PEG which was incorporated onto the cationic liposomes was assayed by using picrate assay method and the incorporation efficiency was $58.4{\pm}1.1%$. Loading efficiency of model drug, doxorubicin, into cationic liposomes or PEG-incorporated cationic liposomes was about $96.0{\pm}0.7%$. Results of intracellular uptake which were evaluated by flow cytometry analysis of doxorubicin loaded liposomes showed that intracellular uptake of PEG-incorporated cationic liposomes was higher than the cationic liposomes or DSPE-mPEG liposomes. In addition, cytotoxicity of PEG-incorporated cationic liposomes was comparable to cationic liposomes. Consequently, the PEG-incorporated cationic liposomes of which surface was incorporated with PEG by ionic complex may be applicable as anticancer drug carriers that can increase therapeutic efficacy.

• 대한치과보철학회지
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• 제36권2호
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• pp.203-244
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• 1998

The human mandible is always under the condition of loading by the various forces extorted by the attached muscles. The loading is an important condition of the stomatognathic system. This condition is composed of the direction and amount of forces of the masticatory muscles, which are controlled by the neuromuscular system, and always influenced by the movement of both opening and closing. Mandible is a strong foundation for the teeth or various prostheses, nevetheless it is a elastic body which accompanies deformation by the external forces on it. The elastic properties of the mandible is influenced by the various procedures such as conventional restorative treatments, osseointegrated implant treatments, reconstructive surgical procedures and so forth. Among the treatments the osseointegrated implant has no periodontal ligaments, which exist around the natural teeth to allow physiologic mobility in the alveolar socket. And so around the osseointegrated implant, there is almost no damping effect during the transmission of occlusal stress and displacements. If the osseointegrated implants are connected by the superstructure for the stabilization and effective distribution of occlusal stresses, the elastic properties of mandible is restricted according to the extent of 'splinting' by the superstructure and implants. To investigate the change of elastic behaviour of the mandible which has osseointegrated implant prosthesis of various numbers of implant installment and span of superstructre, a three dimensional finite element model was developed and analyzed with conditions mentioned above. The conclusions are as follows : 1. The displacements are primarily developed at the area of muscle attachment and distributed all around the mandible according to the various properties of bone. 2. The segmentation in the superstructure has few influence on the distribution of stress and displacement. 3. In the load case of ICP, the concentration of tensional stress was observed at the anterior portion of the ramus($9.22E+6N/m^2$) and at the lingual portion of the symphysis menti($8.36E+6N/m^2$). 4. In the load case of INC, the concentration of tensional stress was observed at the anterior portion of the ramus($9.90E+6N/m^2$) and the concentration of tensional stress was observed at the lingual portion of the symphysis menti($2.38E+6N/m^2$)). 5. In the load case of UTCP, the relatively high concentration of tensional stress($3.66E+7N/m^2$) was observed at the internal surface of the condylar neck.

• 동의생리병리학회지
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• 제24권2호
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• pp.272-277
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• 2010

This experimental study was performed to investigate the antitumor effect of Egg white combined-Chalcanthite (InSan 4, IS4) in xenografted nude mice with NCI-H460 human lung cancer cell. We cultured NCI-H460 cell lines and xenografted them on nude mice. These mice were divided into 3 groups; group with dose of 45 mg/kg IS4 orally, group with dose of 90 mg/kg IS4 orally, and the control group. They had been raised and treated for 28 days. We checked their body weight, tumor weight and volume twice a week, and their absolute organ weight, microhistological observation and biochemical blood analysis at the final day by sacrificing them. We also calculated their tumor inhibition rate (IR), mean survival time and percent increase in life span (% ILS). In this study, we observed that all of the IS4 treated mice have tumor regression, dosage-dependently, compared to the control group. Tumor weight and volume of high dose treated mice were smallest. IR increased in IS4 in a dose-dependent manner. Mean survival time and percent increase in life span (% ILS) in high-dose IS4 treatment group were the highest of the three groups. There was no significant difference in biochemical blood analysis, alanine phopsphatase (ALP), Calcium, creatinine (CRE), alanine transferase (ALT), and aspartate transaminase (AST) levels. The urea nitrogen (UN) level results significantly decreased by IS4 45 and 90 mg/kg (IS4 45 mg/kg, IS4 90 mg/kg, p<0.01). IS4 may have potential anti-tumor effect in a solid tumor induced by NCI-H460 without remarkable side effects.

• 한국환경농학회지
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• 제36권4호
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• pp.293-298
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• 2017

BACKGROUND: Pyrethroids (PYRs) are a widely used insecticide in agriculture and household area. In mammals, PYRs such as deltamethrin is metabolized to 3-phenoxybenzoic acid (3-PBA) in liver that is mainly excreted in urine. This study is designed to single exposure of deltamethrin to rats in a dose-dependent manner and identify the correlation between deltamethrin exposure and its metabolite (3-PBA) in urine. METHODS AND RESULTS: Exposure levels of deltamethrin were control (0 mg/kg bw), low (0.0705 mg/kg bw), medium (0.705 mg/kg bw) and high (7.05 mg/kg bw) dose. Low concentration was derived by ussing Korea predictive operator exposure model (KoPOEM). Dermal exposure persisted for 6 h, and urine specimens were collected for 24 h. The urine matrix was removed after a series of procedures and 3-PBA was analyzed by gas chromatography/mass spectrometry. CONCLUSION: There was a strong correlation ($R^2=0.83$) between the amount of oral exposure to delta me thrin and urinary levelof3-PBAexcreted. In dermal exposure groups of deltamethrin except high-dose, also there was a good correlation between urinary 3-PBA and deltamethrin exposure, but not stronger than in oral deltamethrin exposure groups. Based on these results, therefore, the amount of 3-PBA in urine can be used as a good monitoring indicator that reflexing the exposure level of deltamethrin to human body.

• 대한한의학회지
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• 제31권3호
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• pp.34-46
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• 2010

Objective: This experimental study was performed to examine if Hang-Am-Dan non-boiled water extracts (HAD-N) induce apoptosis in human lung carcinoma NCI-H460 cells in vitro and inhibits the growth of NCI-H460 cell-transplanted solid tumor in vivo. Materials and Methods: We cultured NCI-H460 cell lines and xenografted them to nude mice. The mice were divided into 3 groups, NCI-H460 cell alone, NCI-H460 + 90 mg/kg HAD-N treated group, and NCI-H460 + 180 mg/kg HAD-N treated group, with seven mice per group. HAD-N was orally administrated every day for four weeks. We checked their body weight and tumor weight and volumes two times a week and their absolute organ weight and biochemical blood analysis at the final day by sacrificing them. We also calculated their tumor inhibition rate (IR), mean survival time and percent increase in life span (% ILS). Results: In this study, we observed that all of the HAD-N treated mice got smaller tumors. The more doses of HAD-N used, the less IR showed at the 8th day after starting this experiment. Tumor weight and volume of HAD-N treatment groups also decreased. Mean survival time and percent increase in life span (% ILS) in the high-dose HAD-N treatment groups were higher than those of other groups. The test substances in the blood level UN results showed reduction in the significance in both HAD-N 90 mg/kg and HAD-N 180 mg/kg (p<0.01). The blood level phosphatase results in HAD-N 90 mg/kg group compared to NCI-H460 cell alone group showed a reduction in significance (p<0.05). AST levels HAD-N 180 mg/kg group compared to NCI-H460 cell alone group significance as well (p<0.05). Conclusion: We suggest that the results of the in vivo study showed that HAD-N may have potential as a growth inhibitor of tumor-induced NCI-H460 of nude mice in spite of the shortcomings of this study. More studies to overcome those shortcomings and to find out significant antitumor mechanism will be needed.

• Journal of Ginseng Research
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• 제39권4호
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• pp.398-405
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• 2015

Background: Ginseng has been used as a tonic for invigoration of the human body. In a previous report, we identified a novel candidate responsible for the tonic role of ginseng, designated gintonin. Gintonin induces $[Ca^{2+}]_i$ transient in animal cells via lysophosphatidic acid receptor activation. Gintonin-mediated $[Ca^{2+}]_i$ transient is linked to anti-Alzheimer's activity in transgenic Alzheimer's disease animal model. The previous method for gintonin preparation included multiple steps. The aim of this study is to develop a simple method of gintonin fraction with a high yield. Methods: We developed a brief method to obtain gintonin using ethanol and water. We extracted ginseng with fermentation ethanol and fractionated the extract with water to obtain water-soluble and water-insoluble fractions. The water-insoluble precipitate, rather than the water-soluble supernatant, induced a large $[Ca^{2+}]_i$ transient in primary astrocytes. We designated this fraction as gintonin-enriched fraction (GEF). Results: The yield of GEF was approximately 6-fold higher than that obtained in the previous gintonin preparation method. The apparent molecular weight of GEF, determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was equivalent to that obtained in the previous gintonin preparation method. GEF induced $[Ca^{2+}]_i$ transient in cortical astrocytes. The effective dose (ED50) was $0.3{\pm}0.09{\mu}g/mL$. GEF used the same signal transduction pathway as gintonin during $[Ca^{2+}]_i$ transient induction in mouse cortical astrocytes. Conclusion: Because GEF can be prepared through water precipitation of ginseng ethanol extract and is easily reproducible with high yield, it could be commercially utilized for the development of gintoninderived functional health food and natural medicine.

• Journal of Breast Disease
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• 제6권2호
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• pp.52-59
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• 2018

Purpose: This study aimed to determine whether clinicopathological factors are potentially associated with successful breast-conserving surgery (BCS) after neoadjuvant chemotherapy (NAC) and develop a nomogram for predicting successful BCS candidates, focusing on those who are diagnosed with hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative tumors during the pre-NAC period. Methods: The training cohort included 239 patients with an HR-positive, HER2-negative tumor (${\geq}3cm$), and all of these patients had received NAC. Patients were excluded if they met any of the following criteria: diffuse, suspicious, malignant microcalcification (extent >4 cm); multicentric or multifocal breast cancer; inflammatory breast cancer; distant metastases at the time of diagnosis; excisional biopsy prior to NAC; and bilateral breast cancer. Multivariate logistic regression analysis was conducted to evaluate the possible predictors of BCS eligibility after NAC, and the regression model was used to develop the predicting nomogram. This nomogram was built using the training cohort (n=239) and was later validated with an independent validation cohort (n=123). Results: Small tumor size (p<0.001) at initial diagnosis, long distance from the nipple (p=0.002), high body mass index (p=0.001), and weak positivity for progesterone receptor (p=0.037) were found to be four independent predictors of an increased probability of BCS after NAC; further, these variables were used as covariates in developing the nomogram. For the training and validation cohorts, the areas under the receiver operating characteristic curve were 0.833 and 0.786, respectively; these values demonstrate the potential predictive power of this nomogram. Conclusion: This study established a new nomogram to predict successful BCS in patients with HR-positive, HER2-negative breast cancer. Given that chemotherapy is an option with unreliable outcomes for this subtype, this nomogram may be used to select patients for NAC followed by successful BCS.

• 한국산업보건학회지
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• 제31권2호
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• pp.173-183
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• 2021

Objectives: This study evaluated the skin permeability of lawsone in henna hair dyes to understand the exposure characteristics of henna hair dyes in the human body. It examined the protective effects of protectants by applying protectants A, B, and C to test skin. Methods: Skin absorption tests were conducted using Franz diffusion cells according to OECD test guideline 428. After applying one kind of natural henna hair dye and chemical henna hair dye, respectively, to a standardized pig skin model, samples of receptor fluid were collected at 1h, 3h, 6h, and 24h. The skin permeation of lawsone was determined using HPLC. After the skin absorption experiment, the skin to which hair dye was applied was analyzed to determine the residual amount of lawsone in the skin. Results: The cumulative permeation of both natural and chemical henna hair dyes increased over time, and the natural henna hair dye had a flux value (t=3.194, p<.05) high both in the K_p value (t=3.207, p<.05) and the residual amount (t=22.701, p<.001). For skin treated with a protectant, the cumulative permeation of natural henna hair dye 24h control and the cumulative permeation of protectant A, B, and C increased over time. Flux and K_p values were in the order control > protectant A > protectant C > protectant B. The residual amount (F=4.469, p<.05) was in the order of protectant C > protectant A > protectant B > control. At 3h, the dye application time of natural henna hair dye, the lawsone flux value (F=4.454, p<.05) and K_p value (F=4.455, p<.05) were higher in the control group than in the protectant groups. The 24h cumulative permeation of the chemical henna hair dye increased with time in both the control and the protectant groups, and the flux and K_p values were in the order of protectant A > protectant C > protectant B > control. The residual amount (F=7.901, p<.01) was in the order of protectant B > protectant A> protectant C > control. Conclusions: Within the normal dyeing time for henna hair dye (three hours for natural henna hair dyes and 30 minutes for chemical henna hair dyes) lawsone skin penetration was not observed even when no protective agent was applied. After that time, however, evidence of skin penetration and retention of lawsone and the protective effect of protective agents were observed.