• Title/Summary/Keyword: Department of nuclear medicine

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Protective effects of extracts from six local strains of Pyropia yezoensis against oxidative damage in vitro and in zebrafish model

  • Dai, Yu-Lin;Kim, Gwang Hoon;Kang, Min-Cheol;Jeon, You-Jin
    • ALGAE
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    • v.35 no.2
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    • pp.189-200
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    • 2020
  • Pyropia yezoensis has been used as functional food in East Asia, especially in Korea and Japan, for more than five hundred years. This study aims to evaluate the antioxidant effect of polyphenols and proteins-rich extracts from P. yezoensis (PPPs) against 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH)-induced oxidative cell damage. Among six Korean local strains obtained from Jinhae (JiH), Haenam (HN), Jangheung (JaH), Jindo (JD), Wando (WD), and Sinan (SA) areas, the extracts of P. yezoensis from SA and JD are relatively higher in polyphenols and proteins contents. SA showed the lowest IC50 scavenging activities against 1,1-diphenyl-2-picryl-hydrazyl and alkyl radicals and displayed protective effects against reactive oxygen species (ROS) in AAPH-induced Vero cells. Especially, the PPPs extracts from SA and JD showed protective activities against AAPH-induced apoptosis, as observed by nuclear staining with Hoechst 33342. Furthermore, in vivo studies of the SA extract in zebrafish showed significantly reduced ROS generation, lipid peroxidation, and cell damage. This is the first study, to our knowledge, to evaluate the antioxidant bioactivity of PPP in the Korean Peninsula using a zebrafish model. Due to SA and JD both located in the west coast of Korea, we deduced that the chemical content of the different PPP extracts was mildly influenced by their geographic location, and this alga has potential of protective activity against AAPH-induced ROS both in vitro and in vivo.

[Pt(II)(cis-DACH) (DPPE)] .$2NO_3$: A Novel Class Of Platinum Complex Exhibiting Selective Cytotoxicity to Human Ovarian Carcinoma Cell Lines and Normal Kidney Cells

  • Jung, Jee-Chang;Chu, Min-Ho;Chang, Sung-Goo;Lee, Kyung-Tae;Rho, Young-Soo
    • Biomolecules & Therapeutics
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    • v.5 no.2
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    • pp.125-132
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    • 1997
  • Cisplatin, a platinum-complex, is currently one of the most effective compounds used in the treat-ment of solid tumors. However, its use is limited by severe side effects such as renal toxicity. Our platinum-based drug discovery program is aimed at developing drugs capable of diminishing toxicity and improving selective cytotoxicity. We synthesized new Pt (II) complex analogue containing 1,2-diaminocyclohexane (DACH) as carrier ligand and 1,2-bis (diphenylphosphino) ethane (DPPE) as a leaving group. Furthermore, nitrate was added to improve the solubility. A new series of [Pt(cia-DACH)(DPPE)] . $2NO_3$ (PC) was synthes-ized and characterized by their elemental analysis and by various spectroscopic techniques [infrared (IR), $_{13}$carbon nuclear magnetic resonance (NMR)] .PC demonstrated acceptable and significant antitumor activity against SKOV-3 and OVCAR-3 human ovarian carcinoma cell lines as compared with that of cisplatin. The cytotoxicity of PC in normal cells was found quite less than that of cisplatin using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), ($^3$H)thymidine uptake and glucose consumption tests in rabbit renal proximal tubular cells, human renal cortical cells and tissues. In conclusion, PC is considered to be more selective cytotoxicity toward human ovarian cancer cells than normal human/rabbit kidney cells.

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Effect of Thrombin on the TNF-$\alpha$ Induced IL-6 Production in HUVECs (혈관내피세포에서 트롬빈이 TNF-$\alpha$에 의해 유도되는 IL-6에 미치는 영향)

  • Bae, Jong-Sup;Park, Moon-Ki
    • KSBB Journal
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    • v.25 no.1
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    • pp.11-17
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    • 2010
  • Here, we evaluated the effect of thrombin on the interleukin-6 production induced by tumor-necrosis-factor-$\alpha$ in endothelial cells. It is well known that tumor-necrosis-factor-$\alpha$ mediates inflammatory responses by activation of nuclear factor-kappa-B in endothelial cells. Here, we showed that lower concentration of thrombin decreased the production of interleukin-6 induced by tumor-necrosis-factor-$\alpha$ and this inhibitory effect of thrombin on interleukin-6 production was mediated by interacting with protease-activated-receptor-1. In addition, phosphoinositide-3-kinase was also involved the anti-inflammatory responses by lower concentration of thrombin in endothelial cells. These results suggested that lower concentration of thrombin mediated anti-inflammatory responses by interacting with protease-activated-receptor-1 on the cell membrane and phosphoinositide-3-kinase in the cell. These findings will provide the important evidence in the development of new medicine for the treatment of severe sepsis and inflammatory diseases and good clue for understanding unknown mechanisms by which thrombin showed the pro-inflammatory or anti-inflammatory activities in endothelial cells.

The relationship between the development of musculoskeletal disorders, body mass index, and academic stress in Bahraini University students

  • Tantawy, Sayed A;Rahman, Asma Abdul;Ameer, Maryam Abdul
    • The Korean Journal of Pain
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    • v.30 no.2
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    • pp.126-133
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    • 2017
  • Background: There are many mechanisms in which stress can lead to weight gain thus high a BMI. The endocrine and inflammatory pathway can directly increase abdominal adiposity. Another way in which stress leads to weight gain is through changes in health behaviors. The study aimed to investigate the prevalence of musculoskeletal disorders (MSDs) among healthy students of Ahlia University, and to determine the relationship between the development of MSDs and academic stressors and body mass index. Methods: Self-administered questionnaires were distributed to 94 students aged 18-26 years who were enrolled at various Ahlia University colleges and met other inclusion criteria. The students responded to the standardized Nordic musculoskeletal questionnaire and the modified College Student Stress Inventory regarding musculoskeletal symptoms and academic stressors. Height and weight measurements were also obtained to determine body mass index. Results: A total of 77.66% reported MSDs in one or more body part, with the prevalence being higher among women than among men. The 7-day prevalence of MSDs severe enough to interfere with activities of daily living was 60.64%, and 44.68% by female and male students, respectively. There was a significant relationship between academic stress and MSDs in the neck, shoulders, lower back, and hips, while the relationship between MSDs, and body mass index, academic stress, and grade point average was not significant. Conclusions: The prevalence of MSDs among Ahlia University students was found to be high. Apart from the positive correlation between academic stress and MSDs in certain body parts, other correlations were not significant.

A Survey of the Management of Patient Dose at Medical Center (의료기관의 환자 피폭선량 관리 실태조사)

  • Jeon, Go-Eun;Jin, Gye-Hwan
    • Journal of the Korean Society of Radiology
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    • v.3 no.1
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    • pp.23-28
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    • 2009
  • Medical radiation therapy using radioactive isotope I-131 is an extremely critical part of nuclear medicine. It is important to evaluate patients' radiation exposure dose for the safe handling of radiation in the medical area. Cautions related to patients' exposure to radiation are as follows. First, the dose should not exceed the level required for medical purpose. Second, unnecessary exposure should be avoided. Third, it should be considered carefully first whether the same medical purpose is attainable without the use of radiation. For these purposes, we need to evaluate patients' radiation exposure dose. Thus, in order to promote the safety of patients in medical wards, this study sampled air using an air sampler and measured the radioactivity of the sample using a gamma counter. According to the results of measuring I-131 in medical wards, the highest level, the average and the lowest level were $404.11Bq/m^3$, $228.27Bq/m^3$ and $126.17Bq/m^3$, respectively.

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Evaluation of Validity Glomerular Filtration Rate Measured by Gates Method according Region of Interest (관심 영역 설정에 따른 Gates법 토리여과율의 유효성 평가)

  • Su-Young Park;Sung-Min Ahn
    • Journal of radiological science and technology
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    • v.46 no.5
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    • pp.417-425
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    • 2023
  • The glomerular filtration rate (GFR) has been the subject of much research as a key indicator for diagnosing, treating, and monitoring kidney function. The gamma camera method (Gates method) is simple and allows simultaneous acquisition of GFR and renal scintigraphy for each kidney, however its accuracy is inferior. This study aimed to investigate changes in GFR depending on how region of interest (ROI) are set up, which is one of many factors influencing accuracy. GFR was calculated by setting the ROI for each phase of the image acquisition time (Gates-1: 0~1 minutes, Gates-2: 1~3 minutes, Gates-3: 3~27 minutes), and statistical significance was verified based on probability value 0.05 through ANOVA analysis. While there was no statistically significant difference among results from Gates-1, 2, 3 (p=0.481>0.05), overall results from the Gates method tended to overestimate compared to those from the multiple blood sampling-dual exponential (MBSDE) method. When comparing averages between phases, results from Gates-2 were most similar to those from the MBSDE method. Moreover, paired t-test p-values between MBSDE method and phases were as follows Gates-1: 0.021 (p<0.05), Gates-2: 0.280 (p>0.05), and Gates-3: 0.164 (p>0.05) indicating that only Gates-1 had statistically significant differences compared with MBSDE method. Thus, setting ROI around 2~3 minutes is calculated can aid in accurately determining GFR when Gates Method.

The Measurement of Spatial Dose Rate by Gravity Ventilation after Technegas Scanning (Technegas 스캐닝 후 중력환기에 의한 공간선량율 측정)

  • Kim, Sung-Bin;Won, Do-Yeon
    • Journal of the Korean Society of Radiology
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    • v.13 no.4
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    • pp.667-674
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    • 2019
  • Because examination with technegas produces images through simple diffusion accumulation, the examination room can become contaminated after scan. Therefore, radiation workers and patients awaiting examination will be affected by internal exposure from technegas inhalation. Before and after gravity ventilation, I am trying to find a way to reduce the exposure dose of waiting patients according to a comparative analysis of horizontal spatial dose rates over time. Spatial dose ratio were measured for 10 minutes from various distances and angles around ventilator's location before and after gravity ventilation. Then, mean values, standard deviation and reduction ratio were calculated. The highest reduction rate of gravity ventilation was 95.31% and the highest reduction ratio was 1 to 3 minutes. Therefore, the gravity ventilation could reduce the exposure dose of radiologic technologists, waiting patients, patient guardians and nurses. In conclusion, the reduction of the exposure dose during the technegas ventilation study through gravity ventilation will play a role in optimiging the protection and it is in accordance with the recommended reduction of the medical exposure by ICRP 103.

Two Measurement Considerations for Counting of Background Radioactivity using the Thigh during Thyroid Uptake Rate Test (갑상샘 섭취율 검사 시 대퇴부를 이용한 배후방사능 계측을 위한 2가지 측정 고찰)

  • Do, Yongho;Cho, Youngkwon
    • Journal of the Korean Society of Radiology
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    • v.15 no.4
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    • pp.533-538
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    • 2021
  • 99mTcO4- is used to measure thyroid uptake. When measuring background radioactivity of the thigh, the distance between the detector and the thigh was 20 cm at a position 10 cm above the knee from the knee to the pelvis. At 25 cm, many hospitals are measuring at different distances. The purpose of this study was to study the difference in effectiveness in obtaining the thyroid uptake rate by quantitatively analyzing the uptake rate measurement at two distances. As a result, the average thyroid uptake rate measured at 20 cm in the thigh of 50 patients was 3.532±4.312%, and the average thyroid uptake rate measured at 25 cm was 3.680±4.304%. As a result of the thyroid uptake rate test result, the femoral background radioactivity value measured at a distance of 20 cm was relatively higher than the background radioactivity value measured at a distance of 25 cm, and as a result, the thyroid uptake rate was 0.148% lower.

Effect on Pancreatic Beta Cells and Nerve Cells by Low LET X-ray (Low LET X-ray가 췌장 ${\beta}$ 세포와 신경세포에 미치는 효과)

  • Park, Kwang-Hun;Kim, Kgu-Hwan
    • Journal of radiological science and technology
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    • v.37 no.1
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    • pp.21-28
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    • 2014
  • Cultured pancreatic beta cells and nerve cells, it is given normal condition of 10% FBS (fetal bovine serum), 11.1 mM glucose and hyperglycemia codition of 1% FBS, 30 mM glucose. For low LET X-ray irradiated with 0.5 Gy/hr dose-rate(total dose: 0.5 to 5 Gy). Survival rates were measured by MTT assay. When non irradiated, differentiated in the pancreatic beta cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a small reduction. However increasing the total dose of X-ray, the survival rate of normal conditions decreased slightly compared to the survival rate of hyperglycemia conditions, the synergistic effect was drastically reduced. When non irradiated, undifferentiated in the nerve cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a large reduction. As the cumulative dose of X-ray normal conditions and hyperglycemia were all relatively rapid cell death. But the rate of decreased survivals by almost parallel to the reduction proceed and it didn't show synergistic effect.

Development of $^1H-^{31}P$ Animal RF Coil for pH Measurement Using a Clinical MR Scanner (임상용 MR에서 pH 측정을 위한 동물 실험용 $^1H-^{31}P$ RF 코일 개발)

  • Kim, Eun Ju;Kim, Daehong;Lee, Sangwoo;Heo, Dan;Lee, Young Han;Suh, Jin-Suck
    • Investigative Magnetic Resonance Imaging
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    • v.18 no.1
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    • pp.52-58
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    • 2014
  • Purpose : To establish a pH measurement system for a mouse tumor study using a clinical scanner, to develop the $^1H$ and 31P radio frequency (RF) coil system and to test pH accuracy with phantoms. Materials and Methods: The $^1H$ and the $^{31}P$ surface coils were designed to acquire signals from mouse tumors. Two coils were positioned orthogonally for geometric decoupling. The pH values of various pH phantoms were calculated using the $^1H$ decoupled $^{31}P$ MR spectrum with the Henderson-Hasselbalch equation. The calculated pH value was compared to that of a pH meter. Results: The mutual coil coupling was shown in a standard $S_{12}$. Coil coupling ($S_{12}$) were -73.0 and -62.3 dB respectively. The signal-to-noise ratio (SNR) obtained from the homogeneous phantom $^1H$ image was greater than 300. The high resolution in vivo mice images were acquired using a $^{31}P$-decoupled $^1H$ coil. The pH values calculated from the $^1H$-decoupled $^{31}P$ spectrum correlated well with the values measured by pH meter ($R^2$=0.97). Conclusion: Accurate pH values can be acquired using a $^1H$-decoupled $^{31}P$ RF coil with a clinical scanner. This two-surface coil system could be applied to other nuclear MRS or MRI.