• Proceedings of the PSK Conference
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• 2003.04a
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• pp.309.2-310
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• 2003

The pharmacokinetics and pharmacodynamics of torasemide were evaluated after an intravenous administration of the same total dose of torasemide at a dose of 1 mg/kg to rabbits with different infusion times, 1 min (treatment I), 30 min (treatment II), and 2 h (treatment III). The loss of water and electrolytes in urine induced by torasemide was immediately replaced with infusion of equal volume of lactated Ringer…s solution. (omitted)

• The Journal of Korean Society for Radiation Therapy
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• v.14 no.1
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• pp.175-186
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• 2002

The purpose of this study is directly measure and evaluate about absorbed dose change according to nominal energy and electron cone or medical accelerator on isodose curve, percentage depth dose, contaminated X-ray, inhomogeneous tissue, oblique surface and irradiation on intracavitary that electron beam with high energy distributed in tissue, and it settled standard data of hish energy electron beam treatment, and offer to exactly data for new dote distribution modeling study based on experimental resuls and theory. Electron beam with hish energy of $6{\sim}20$ MeV is used that generated from medical linear accelerator (Clinac 2100C/D, Varian) for the experiment, andwater phantom and Farmer chamber md Markus chamber und for absorbe d dose measurement of electron beam, and standard absorbed dose is calculated by standard measurements of International Atomic Energy Agency(IAEA) TRS 277. Dose analyzer (700i dose distribution analyzer, Wellhofer), film (X-OmatV, Kodak), external cone, intracavitary cone, cork, animal compact bone and air were used for don distribution measurement. As the results of absorbed dose ratio increased while irradiation field was increased, it appeared maximum at some irradiation field size and decreased though irradiation field size was more increased, and it decreased greatly while energy of electron beam was increased, and scattered dose on wall of electron cone was the cause. In percentage depth dose curve of electron beam, Effective depth dose(R80) for nominal energy of 6, 9, 12, 16 and 20 MeV are 1.85, 2.93, 4.07, 5.37 and 6.53 cm respectively, which seems to be one third of electron beam energy (MeV). Contaminated X-ray was generated from interaction between electron beam with high energy and material, and it was about $0.3{\sim}2.3\%$ of maximum dose and increased with increasing energy. Change of depth dose ratio of electron beam was compared with theory by Monte Carlo simulation, and calculation and measured value by Pencil beam model reciprocally, and percentage depth dose and measured value by Pencil beam were agreed almost, however, there were a little lack on build up area and error increased in pendulum and multi treatment since there was no contaminated X-ray part. Percentage depth dose calculated by Monte Carlo simulation appeared to be less from all part except maximum dose area from the curve. The change of percentage depth dose by inhomogeneous tissue, maximum range after penetration the 1 cm bone was moved 1 cm toward to surface then polystyrene phantom. In case of 1 cm and 2 cm cork, it was moved 0.5 cm and 1 cm toward to depth, respectively. In case of air, practical range was extended toward depth without energy loss. Irradiation on intracavitary is using straight and beveled type cones of 2.5, 3.0, 3.5 $cm{\phi}$, and maximum and effective $80\%$ dose depth increases while electron beam energy and size of electron cone increase. In case of contaminated X-ray, as the energy increase, straight type cones were more highly appeared then beveled type. The output factor of intracavitary small field electron cone was $15{\sim}86\%$ of standard external electron cone($15{\times}15cm^2$) and straight type was slightly higher then beveled type.

• Progress in Medical Physics
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• v.31 no.2
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• pp.9-19
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• 2020

Purpose: This study aims to develop a multi-purpose electron beam irradiation device for preclinical research and material testing using the research electron linear accelerator installed at the Dongnam Institute of Radiological and Medical Sciences. Methods: The fabricated irradiation device comprises a dual scattering foil and collimator. The correct scattering foil thickness, in terms of the energy loss and beam profile uniformity, was determined using Monte Carlo calculations. The ion-chamber and radiochromic films were used to determine the reference dose-rate (Gy/s) and beam profiles as functions of the source to surface distance (SSD) and pulse frequency. Results: The dose-rates for the electron beams were evaluated for the range from 59.16 Gy/s to 5.22 cGy/s at SSDs of 40-120 cm, by controlling the pulse frequency. Furthermore, uniform dose distributions in the electron fields were achieved up to approximately 10 cm in diameter. An empirical formula for the systematic dose-rate calculation for the irradiation system was established using the measured data. Conclusions: A wide dose-rate range electron beam irradiation device was successfully developed in this study. The pre-clinical studies relating to FLASH radiotherapy to the conventional level were made available. Additionally, material studies were made available using a quantified irradiation system. Future studies are required to improve the energy, dose-rate, and field uniformity of the irradiation system.

• The Journal of the Korea Contents Association
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• v.19 no.8
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• pp.276-283
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• 2019

The purpose of this study is to evaluate the usefulness of automatic exposure control (AEC) by analyzing entrance surface dose (ESD) and entropy on using automatic exposure and manual exposure. The experimental method was to measure the dose by placing a semiconductor dosimeter on the Rando Phantom for the Pelvis, Abdomen, Skull, and Chest regions. The DICOM file was simultaneously acquired and then entropy was analyzed by using Matlab. As a result, when using the automatic exposure control, dose of all sites was lower than manual exposure's dose and entropy was high. In addition, paired t-test was performed for each item and p<0.05 was found in each item. In conclusion, the use of automatic exposure control can be a useful method to contribute to the optimization of the exposure dose and the image quality by reducing the amount of unnecessary radiation amount and information loss that can occur in X-ray examination.

• Journal of radiological science and technology
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• v.42 no.1
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• pp.61-66
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• 2019

The purpose of this study was to improve the unstable treatment posture by placing the Carbon fabric blanket on the couch which was used for the patient fixation for the unstable posture from the severe pain caused by the neuromuscular pressure of the spinal metastatic cancer patient and to analyze the dose difference caused by the energy loss of high energy radiation. Using a linear accelerator, a FC-65G was installed at a depth of 5 cm at a solid phantom at 6 MV and 10 MV energies. The SAD was 100 cm, Gantry angle was $0^{\circ}$, a Cotton and Carbon blanket with a thickness of 1 cm on the couch, The blankets were placed on the couch and the dose was measured according to field size. For the dose measurement, and the dose was measured at 100 MU each time, and the mean value was calculated by repeating the measurement three times in order to reduce the error. The results showed that the difference rate in dose between Carbon blanket and Cotton blanket was respectively -0.54% and -0.75% based on the absence of the blanket(Non). Therefore, it is considered that the use of Carbon fabric blanket, which reduces the patient's pain and does not affect the depth dose, may be useful during radiation therapy of the spine metastasis cancer.

• The Korean Journal of Nuclear Medicine
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• v.4 no.2
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• pp.55-66
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• 1970

Reappraisal measurements of apparent half survival time of red cell by $^{51}Cr$ method was made and effects of blood-letting over red cell survival were observed. The study was performed on 53 normal male subjects under three different experimental conditions. 1. Group 1 Mean $^{51}Cr$ red cell half survival by ACD wash method was 29.7 days. $T\frac{1}{2}$ of Ascorbic acid method was 29.0 days in group with 100 mg dose and 29.1 days in group with 50 mg dose respectively. There was no difference between these two methods in regards to red cell half survival. No difference were noted in amount of ascorbic acid administered. 2. Group 2 As daily amount of blood loss is increased the shortening of red cell half survival was noted. Rapid phase was seen when blood loss ranged 10 to 25 ml per day, while slow phase noted when more loss amounted 25 ml or more daily. Thus, it was clear that there was more than an exponential relation between $T\frac{1}{2}$ and the amount of blood loss. 3. Group 3 $T\frac{1}{2}$ measured by cpm per whole blood was within normal range and $T\frac{1}{2}$ measured by cpm per red cell mass showed shortening tendency when compared with the former in the group measured after blood loss (from 25 ml daily up to 100 ml daily in 10 days). In the group with rather constant blood loss of 100 ml daily for 10 consecutive days revealed the significant difference in two measurements (P<0.01). 4. $T\frac{1}{2}$ in non-steady state When red cell production is increased compared with red cell destruction, $T\frac{1}{2}$ measured by cpm per red cell mass being shorter than that by cpm per whole blood. Shortening of $T\frac{1}{2}$ measured by cpm per whole blood is more prominent. if red cell destrction is enhanced and exceeds production. 5. It is clear that when expressing red cell destruction rate, $T\frac{1}{2}$ measured by cpm per whole blood is more adequate and production more consistent with cpm red cell mass. 6. $T\frac{1}{2}$ measured during blood-letting, when corrected by amount of blood loss, it remains normal. It is erroneous to use conventional equational when measuring $T\frac{1}{2}$ in non-steady. $T\frac{1}{2}$ measured by cpm per whole blood is considred more applicable in clinical evaluation.

• Toxicological Research
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• v.22 no.2
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• pp.117-126
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• 2006

This study was conducted to obtain the acute information of the oral dose toxicity of lyophilized water extract of Picrorrhiza Rhizoma (PR) - dried underground stem of Picrorrhiza kurroa, having various pharmacological effects, in male and female mice. In order to calculate 50% lethal dose ($LD_{50}$), approximate lethal dose and target organs, test article was administered once by oral gavage to male and female ICR mice at 2000, 1000, 500 and 250 mg/kg. The mortality and changes on body weight, clinical signs and gross observation were monitored during 14 days after dosing with organ weight and histopathology of 12 types of principle organs. As the results, we could not find any mortality, clinical signs, changes in the body weight and gross findings except for hair loss, a significantly (p<0.05) increase of body weight gains in 2000mg/kg of PR extracts-dosing male group and some sporadic gross findings. In addition, no meaningful changes on the organ weight and histopathology of 12 types of principle organs were detected in the present study except for significantly (p<0.05) but dose independent changes on thymus, spleen and popliteal lymph nodes weights, and some sporadic accidental histopathological findings. The results obtained in this study suggest that the PR extract is non-toxic in mice and is therefore likely to be safe for clinical use. The $LD_{50}$ and approximate lethal dose of PR extracts in both female and male mice were considered as over 2000 mg/kg.

• Nutrition Research and Practice
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• v.12 no.6
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• pp.535-540
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• 2018

BACKGROUND/OBJECTIVES: Propolis has a rich source of bioactive compounds and has renal and hepatic protective properties. The purpose of this study was to investigate the beneficial effect of hydro-ethanolic extract of propolis against paracetamol-induced liver damage and impairment of kidney function, as well as hematological changes in rats. MATERIALS/METHODS: Six groups of rats were used; the first group was served as a control; the second and third groups were treated by propolis extract at a dose of 50 and 100 mg/kg.B.WT. respectively; the fourth group was treated by paracetamol (200 mg/kg.B.WT.); the fifth group was treated by propolis (50 mg/kg.B.WT.) for eight days and then received similar dose of propolis for following seven days with paracetamol at a dose of 200 mg/kg.B.WT. daily for the seven days; and the sixth group was treated with propolis (100 mg/kg.B.WT.) for eight days and then received similar dose of propolis for following seven days with paracetamol at a dose of 200 mg/kg.B.WT. daily for the seven days. All the animals were treated for a period of 15 days. At the end of the experimental period, blood samples were collected for measurement of the liver enzymes, serum albumin, protein and creatinine, blood urea nitrogen, hematological parameters, and urine volume, protein and albumin. RESULTS: Paracetamol over dose significantly lowered hemoglobin, serum total protein, albumin, and uric acid, while it significantly increased blood creatinine, blood urea nitrogen, alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase activities, white blood cells, and platelet count as compared to the control. However, these alterations were significantly attenuated by the use of propolis extract and the effect was dose dependent. Interestingly, propolis prevented paracetamol induced proteinuria, low hemoglobin and body weight loss. CONCLUSIONS: Propolis significantly prevented paracetamol induced renal, hepatic and hematological toxicity and might be useful in the management of liver and renal diseases particularly proteinuria.

• Nuclear Engineering and Technology
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• v.55 no.2
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• pp.696-706
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• 2023

Consequences of an anticipated Beyond Design Basis Accident (BDBA) Long-Term Station Blackout (LTSBO) event with complete loss of grid power in the VVER-1200 reactor of Rooppur Nuclear Power Plant (NPP) of Unit-1 are assessed using the RASCAL 4.3 code. This study estimated the released radionuclides, received public radiological dose, and ground surface concentration considering 3 accident scenarios of International Nuclear and Radiological Event Scale (INES) level 7 and two meteorological conditions. Atmospheric transport, dispersion, and deposition processes of released radionuclides are simulated using a straight-line trajectory Gaussian plume model for short distances and a Gaussian puff model for long distances. Total Effective Dose Equivalent (TEDE) to the public within 40 km and radionuclides contribution for three-dose pathways of inhalation, cloudshine, and groundshine owing to airborne releases are evaluated considering with and without passive safety Emergency Core Cooling System (ECCS) in dry (winter) and wet (monsoon) seasons. Source term and their release rates are varied with the functional duration of passive safety ECCS. In three accident scenarios, the TEDE of 10 mSv and above are confined to 8 km and 2 km for the wet and dry seasons, respectively in the downwind direction. The groundshine dose is the most dominating in the wet season while the inhalation dose is in the dry season. Total received doses and surface concentration in the wet season near the plant are higher than those in the dry season due to the deposition effect of rain on the radioactive substances.

• Childhood Kidney Diseases
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• v.21 no.1
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• pp.35-39
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• 2017

Azathioprine is commonly used as immunosuppressive therapy for various inflammatory diseases including chronic glomerulonephritis. Myelosuppression is a common side effect of azathioprine, resulting in the need for dose reduction. However, severe pancytopenia or alopecia is not often encountered. Here, we report a case of severe myelosuppression, and alopecia totalis that occurred after azathioprine treatment in a patient with IgA nephropathy. A 10-year-old boy with IgA nephropathy was treated with oral deflazacort and later with azathioprine. After 4 weeks, the patient complained of hair loss, and despite a dose reduction in azathioprine, he developed bone marrow suppression and alopecia totalis in two weeks. The blood indices and alopecia of the patient had returned to normal after azathioprine withdrawal and 3 consecutive doses of granulocyte colony-stimulating factor. We suggest that physicians remain vigilant to the side effects of azathioprine. Unusual hair loss after azathioprine treatment might suggest a defect in the metabolism of the drug, warranting the discontinuation of azathioprine to prevent more severe side effects.