• Title/Summary/Keyword: Human Exposure

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Comparison of Noise and Doses of Low Dose and High Resolution Chest CT for Automatic Tube Current Modulation and Fixed Tube Current Technique using Glass Dosimetry (유리선량계를 이용한 관전류자동조절기법과 고정관전류기법에서 저선량 및 고해상 흉부CT의 노이즈 및 선량 비교)

  • Park, Tae Seok;Han, Jun Hee;Jo, Seung Yeon;Lee, Eun Lim;Jo, Kyu Won;Kweon, Dae Cheol
    • Journal of Radiation Industry
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    • v.11 no.3
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    • pp.131-137
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    • 2017
  • To compare the radiation dose and image noise of low dose computed tomography (CT) and high resolution CT using the fixed tube current technique and automatic tube current modulation (CARE Dose 4D). Chest CT and human anthropomorphic phantom were used the RPL (radiophotoluminescence) dosimeters. For image evaluation, standard deviation of mean CT attenuation coefficient and CT attenuation coefficient was measured using ROI analysis function. The effective dose was calculated using CTDIvol and DLP. CARE Dose 4D was reduced by 74.7% and HRCT by 64.4% compared to the fixed tube current technique in low dose CT of chest phantom. In CTDIvol and DLP, the dose of CARE Dose 4D was reduced by fixed tube current technique. For effective dose, CARE Dose 4D was reduced by 47% and HRCT by 46.9% compared to the fixed tube current method, and the dose of CARE Dose 4D was significantly different (p<.05). Noise in the image was higher than that in the fixed tube current technique. Noise difference in the image of CARE Dose 4D in low dose CT was significant (p<.05). The low radiation dose and the noise difference of the CARE Dose 4D were compared with the fixed tube current technique in low dose CT and HRCT using chest phantom. The radiation doses using CARE Dose 4D were in accordance with the national and international dose standards. CARE Dose 4D should be applied to low dose CT and HRCT for clinical examination.

The interpretation of Laughter in a Saseol-sijo about Waiting (기다림의 사설시조에 나타난 웃음의 해석 -'임이 오마 하거늘'을 중심으로-)

  • Song, Ji-eon
    • Journal of Korean Classical Literature and Education
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    • no.32
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    • pp.261-285
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    • 2016
  • Saseol-sijo, a form of sijo with longer verses, still affords pleasure to modern readers, even when it is read without the original performance context. In this study, I focused on Saseol-sijo that induces laughter through exaggeration and caricature while singing about eagerly waiting for a lover who has left. These texts describe concurrently the emotions that are contradictory to each other, such as nostalgia and laughter. In addition, this feature reflects human's inner emotions that are not unified but rather change dynamically. Craving creates a sense of nostalgia, and also produces a comical element in nostalgia, so that nostalgia and laughter can be co-exist without conflict. In this study, 'semiotic square' was applied as the framework for interpreting the Saseol-sijo, which demonstrates the coexistence of inconsistent meanings. As a result, a Saseol-sijo which sings about waiting for a lover can be interpreted through contraires such as prohibition and authorization, craving and concerns, exposure and concealment and concentration and dispersion. The nostalgic laughter in Saseol-sijo is generally based on the conflict between the craving self and the restrictive world. A character consumed by craving may seem ridiculous and pathetic in the view of others. However, people in general would find sympathetic humor and identify with characters who portray their weaknesses or repeat their mistakes. After all, this is the laughter of compassion and reflection which Saseol-sijo evoke.

Evaluation of Effective Dose with National Diagnostic Reference Level using Monte-Carlo Simulation (몬테카를로 시뮬레이션을 이용한 국내 일반엑스선검사 진단참고수준의 유효선량 평가)

  • Lee, Seung-Youl;Seoung, Youl-Hun
    • Journal of the Korean Society of Radiology
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    • v.15 no.7
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    • pp.1041-1047
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    • 2021
  • In this study, the effective dose for frequently general radiography among the diagnostic reference level (DRL) for examinations provided by the government in Korea was evaluated using the Monte Carlo N-Particle eXtended (MCNPX) simulation tool. We were selected to evaluate for a total of 5 examination sites which included head anterior-posterior, chest (posterior-anterior, lateral), abdomen anterior-posterior and pelvis anterior-posterior. Physical conditions such as tube voltage and tube current used in MCNPX simulation were used in domestic conditions of the Korea Disease Control and Prevention Agency (KDCA). To evaluate domestic medical radiation exposure, we used the HDRK-Man computerized human phantom manufactured based on the international standard ICRP 103 that was applied to the MCNPX simulation. The phantom could represent the standard body shape of Koreans. As a results, the effective dose corresponding to the DRL based on adult males of head anterior-posterior position was 0.086 mSv, chest posterior-anterior position was 0.05 mSv, chest lateral was 0.354 mSv, abdomen anterior-posterior position was 0.548 mSv, and pelvis anterior-posterior position was 0.451 mSv.

HSP90 inhibitor, AUY922, debilitates intrinsic and acquired lapatinib-resistant HER2-positive gastric cancer cells

  • Park, Kang-Seo;Hong, Yong Sang;Choi, Junyoung;Yoon, Shinkyo;Kang, Jihoon;Kim, Deokhoon;Lee, Kang-Pa;Im, Hyeon-Su;Lee, Chang Hoon;Seo, Seyoung;Kim, Sang-We;Lee, Dae Ho;Park, Sook Ryun
    • BMB Reports
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    • v.51 no.12
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    • pp.660-665
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    • 2018
  • Human epidermal growth factor receptor 2 (HER2) inhibitors, such as trastuzumab and lapatinib are used to treat HER2-positive breast and gastric cancers. However, as with other targeted therapies, intrinsic or acquired resistance to HER2 inhibitors presents unresolved therapeutic problems for HER2-positive gastric cancer. The present study describes investigations with AUY922, a heat shock protein 90 (HSP90) inhibitor, in primary lapatinib-resistant (ESO26 and OE33) and lapatinib-sensitive gastric cancer cells (OE19, N87, and SNU-216) harboring HER2 amplification/over-expression. In order to investigate whether AUY922 could overcome intrinsic and acquired resistance to HER2 inhibitors in HER2-positive gastric cancer, we generated lapatinib-resistant gastric cancer cell lines (OE19/LR and N87/LR) by continuous exposure to lapatinib in vitro. We found that activation of HER2 and protein kinase B (AKT) were key factors in inducing intrinsic and acquired lapatinib-resistant gastric cancer cell lines, and that AUY922 effectively suppressed activation of both HER2 and AKT in acquired lapatinib-resistant gastric cancer cell lines. In conclusion, AUY922 showed a synergistic anti-cancer effect with lapatinib and sensitized gastric cancer cells with intrinsic resistance to lapatinib. Dual inhibition of the HSP90 and HER2 signaling pathways could represent a potent therapeutic strategy to treat HER2-positive gastric cancer with intrinsic and acquired resistance to lapatinib.

Mime Elements in Court Hagmu ; focusing on literature and expression of current practice (궁중 학무에 나타난 마임적 요소 - 문헌과 현행의 표출 현상을 중심으로 -)

  • Son, Sun Sook
    • (The) Research of the performance art and culture
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    • no.18
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    • pp.47-72
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    • 2009
  • This study explores mime elements of court Hagmu(鶴舞) in literature and what is expressed in the practice of current Hagmu and examines what has been changed while others are kept intact. The content of Hagmu is that "attracted by lotus flowers in a pond, cranes dance around and peck at them, when the blossoms open wide with a girl [dancer] inside, upon which the surprised cranes fly away." The dance consists of 4 steps: the first step is for the entrance of cranes; in the second step the cranes dance moving across jidang(池塘) and the north; in the third step the cranes are curious about the lotus calyces, yeontong(蓮筒); and the cranes withdraw in the fourth step. The literature suggests that the dancing courses on the stage are limited to the east, the west, the south, and the north. The movement is limited to naeson (內旋) only in mujin(舞進) and mutoe(舞退). Furthermore, the gaze is only allowed toward the north and jidang. Motions are limited to naejog(內足), oego (外顧), and naego(內顧). However, the mime elements of current Hagmu are attributed to the effort of translating crane's life into a realistic story. It relates the life of cranes to that of human beings and implies love in it. Finally, the court Hagmu has entered the real world out of the literature, enriched with new elements. Under the transition from literature to practice the diversity of expression is added while the elements related with court codes such as courses, movements, directions, and motions are kept intact. These limitations, however, are coupled with the sensitive 'love' and the exposure of dancing instruments intrigues audience and creates dramatic effect. In conclusion the significance of mime elements in court Hagmu is in enhancing communication with audience.

Arsenic species in husked and polished rice grains grown at the non-contaminated paddy soils in Korea (국내 비오염 논토양에서 재배한 현미와 백미 중 비소화학종 함량)

  • Kim, Da-Young;Kim, Ji-Young;Kim, Kye-Hoon;Kim, Kwon-Rae;Kim, Hyuck-Soo;Kim, Jeong-Gyu;Kim, Won-Il
    • Journal of Applied Biological Chemistry
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    • v.61 no.4
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    • pp.391-395
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    • 2018
  • There is an increasing concern over arsenic (As) contamination of paddy soil and rice with regard to food safety. This study was conducted to investigate total and inorganic As concentration in one hundred husked and polished rice samples collected at the non-contaminated paddy soil in Korea. Arsenic species in rice samples were extracted using 1% nitric acid ($HNO_3$) with a microwave oven and were measured using high performance liquid chromatography coupled with inductively coupled plasma-mass spectrometry. Mean concentrations of total As in husked rice and polished rice were 0.18 and $0.11mg\;kg^{-1}$, respectively. Also, average inorganic As concentrations in husked rice and polished rice were 0.11 and $0.07mg\;kg^{-1}$, respectively. These levels are lower than the standard guideline value 0.35 and $0.2mg\;kg^{-1}$ for inorganic As in husked and polished rice recommended by Codex Committee on Contaminants in Foods and Ministry of Food and Drug Safety, respectively. The mean of the inorganic As ratio for the total amount of As was 0.65 and 0.67 for husked rice and polished rice, respectively, and the range was from 0.08 to 1.0. For health risk assessment, the average value of cancer risk probability was $9.24{\times}10^{-5}$ and ranged from $2.30{\times}10^{-5}$ to $1.90{\times}10^{-5}$. Therefore, human exposure to As through dietary intake of surveyed rice samples might considered to be a low health risk.

1,2-Dichloropropane (1,2-DCP)-Induced Angiogenesis in Dermatitis

  • Jin, Meiying;Hong, Youngeun;Lee, Hyunji;Tran, Quangdon;Cho, Hyeonjeong;Kim, Minhee;Kwon, So Hee;Kang, Nak Heon;Park, Jisoo;Park, Jongsun
    • Toxicological Research
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    • v.35 no.4
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    • pp.361-369
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    • 2019
  • 1,2-Dichloropropane (1,2-DCP) has been used as an industrial solvent and a chemical intermediate, as well as in soil fumigants. Human exposure may occur during its production and industrial use. The target organs of 1,2-DCP are the eyes, respiratory system, liver, kidneys, central nervous system, and skin. Repeated or prolonged contact may cause skin sensitization. In this study, 1,2-DCP was dissolved in corn oil at 0, 2.73, 5.75, and 8.75 mL/kg. The skin of mice treated with 1,2-DCP was investigated using western blotting, hematoxylin and eosin staining, and immunohistochemistry. 1,2-DCP was applied to the dorsal skin and both ears of C57BL/6J mice. The thickness of ears and the epidermis increased significantly following treatment, and the appearance of blood vessels was observed in the dorsal skin. Additionally, the expression of vascular endothelial growth factor, which is tightly associated with neovascularization, increased significantly. The levels of protein kinase-B (PKB), phosphorylated PKB, mammalian target of rapamycin (mTOR), and phosphorylated mTOR, all of which are key components of the phosphoinositide 3-kinase/PKB/mTOR signaling pathway, were also enhanced. Taken together, 1,2-DCP induced angiogenesis in dermatitis through the PI3K/PKB/mTOR pathway in the skin.

Growth rates and nitrate uptake of co-occurring red-tide dinoflagellates Alexandrium affine and A. fraterculus as a function of nitrate concentration under light-dark and continuous light conditions

  • Lee, Kyung Ha;Jeong, Hae Jin;Kang, Hee Chang;Ok, Jin Hee;You, Ji Hyun;Park, Sang Ah
    • ALGAE
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    • v.34 no.3
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    • pp.237-251
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    • 2019
  • The dinoflagellate genus Alexandrium is known to often form harmful algal blooms causing human illness and large-scale mortality of marine organisms. Therefore, the population dynamics of Alexandrium species are of primary concern to scientists and aquaculture farmers. The growth rate of the Alexandrium species is the most important parameter in prediction models and nutrient conditions are critical parameters affecting the growth of phototrophic species. In Korean coastal waters, Alexandrium affine and Alexandrium fraterculus, of similar sizes, often form red-tide patches together. Thus, to understand bloom dynamics of A. affine and A. fraterculus, growth rates and nitrate uptake of each species as a function of nitrate ($NO_3$) concentration at $100{\mu}mol\;photons\;m^{-2}s^{-1}$ under 14-h light : 10-h dark and continuous light conditions were determined using a nutrient repletion method. With increasing $NO_3$ concentration, growth rates and $NO_3$ uptake of A. affine or A. fraterculus increased, but became saturated. Under light : dark conditions, the maximum growth rates of A. affine and A. fraterculus were 0.45 and $0.42d^{-1}$, respectively. However, under continuous light conditions, the maximum growth rate of A. affine slightly increased to $0.46d^{-1}$, but that of A. fraterculus largely decreased. Furthermore, the maximum nitrate uptake of A. affine and A. fraterculus under light : dark conditions were 12.9 and $30.1pM\;cell^{-1}d^{-1}$, respectively. The maximum nitrate uptake of A. affine under continuous light conditions was $16.4pM\;cell^{-1}d^{-1}$. Thus, A. affine and A. fraterculus have similar maximum growth rates at the given $NO_3$ concentration ranges, but they have different maximum nitrate uptake rates. A. affine may have a higher conversion rate of $NO_3$ to body nitrogen than A. fraterculus. Moreover, a longer exposure time to the light may confer an advantage to A. affine over A. fraterculus.

Obesity Regulation through Gut Microbiota Modulation and Adipose Tissue Browning (장내 미생물의 조절과 지방세포의 갈색지방화를 통한 비만 조절 연구)

  • Cho, Yejin;Shamim, Rahman Md.;Kim, Yong-Sik
    • Journal of Life Science
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    • v.29 no.8
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    • pp.922-940
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    • 2019
  • Obesity, represented by abnormal fat accumulation due to an imbalance between energy intake and expenditure, is a major public health issue worldwide, leading to multiple noncommunicable diseases, including atherosclerosis, hypertension, type 2 diabetes, and cancer. Diverse solutions have been proposed to combat obesity. Attention has focused on two types of adipose tissues as a promising therapeutic target in obesity: traditional brown and beige or brite. Unlike energy-storing white adipose (endocrine) tissue, traditional brown adipose tissue and beige adipose tissue have energy-dissipating thermogenic properties. Both types of tissue are present in adult humans and inducible through external stimuli, such as cold exposure, ${\beta}3$-adrenergic receptor agonists, and phytochemicals. Among these stimuli, microbiota present in the human intestinal tract participate in multiple metabolic activities. Modulation of gut microbiota may offer a potent and possibly curative strategy against various metabolic diseases. Numerous studies have focused on the effects of established antiobesity treatments on the gut microenvironment or brown-adipose-tissue activation. In this review, we focus mainly on stimuli known to alleviate obesity, weight gain, and metabolic diseases, in addition to known and possible inter-relations between gut microbiota modulation and similar interventions and adipose tissue browning. The findings may pave the way toward new strategies against obesity.

Induction of Apoptosis and Growth-Inhibition by Thymoquinone in ACHN and GP-293 Cell Lines in Comparable with Cis-Platinum

  • Shahraki, Samira;Mohebbati, Reza;Shafei, Mohammad Naser;Mahmoudi, Mahmoud;Hosseinian, Sara;Parhizgar, Soghra;Yazd, Zohreh Naji Ebrahimi;Heravi, Nazanin Entezari;Abadi, Reza Nejad Shahrokh;Khajavirad, Abolfazl
    • Journal of Pharmacopuncture
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    • v.22 no.3
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    • pp.176-183
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    • 2019
  • Objective: In the current work, we investigated the cytotoxic and apoptotic effects of Thymoquinone (TQ), an active compound of Nigella sativa (N. sativa) and Cis-platinum, on normal renal epithelial (GP-293) and human renal adenocarcinoma cell lines (ACHN). Methods: GP-293 and ACHN cell lines were cultured in Dulbecco's modified Eagle's medium (DMEM) with 10% Fetal bovine serum (FBS) and 1% penicillin plus streptomycin antibiotic. The MTT assay was used for cellular viability assessment. Viability of cells was observed using inverted light microscope 24, 48 and 72 h after exposure of the cells to various concentrations of TQ (1, 2.5, 5, 10, 50 and $100{\mu}g/ml$) and Cis-platinum (0.5, 1, 1.5, 2, 3, 6 and $12.5{\mu}g/ml$). Moreover, apoptosis was analyzed with a flow-cytometry method. The untreated cells were considered as control group. Results: Morphological changes such as reduced cell number and increased intercellular distance and reduced cell viability in ACHN and GP-293cell lines were observed in both TQ and Cis- platinum groups; however, Cis-platinum had greater effect on ACHN cell line than GP-293 cell line. In addition, GP-293 cell line was more sensitive to TQ compared to ACHN cell line. Furthermore, TQ and Cis-platinum had apoptotic effects on both ACHN and GP-293 cell lines. Conclusion: Our findings demonstrated that TQ and Cis-platinum had cytotoxic and apoptotic effects on both cell lines, However, GP-293 cell line was more sensitive to TQ. Additionally, Cis-platinum was more effective on ACHN cell line than on GP-293 cell line.