• Nuclear Engineering and Technology
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• v.54 no.8
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• pp.3176-3180
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• 2022

A gamma irradiator is a well-developed installation for gamma radiation sterilization. A "shuffle-dwell" mode is preferable for high dose applications. A novel configuration of a shuffle-dwell gamma irradiator is proposed to increase energy utilization and throughput, which would result in higher profitability. While the minimum distance between any irradiation position and each source pencil, the minimum distance between the neighboring irradiation positions and the size of source pencils are kept the same as the current configuration, the irradiation positions and source pencils are rearranged based on the fact that radiation is emitted in an isotropic fashion. The computational results suggest that the proposed configuration requires an 8.7% smaller area and exposes the product to 11.8% more gamma radiation in a 10.7% shorter irradiation time. In other words, the proposed configuration needs a smaller area and shorter irradiation time to have a better performance compared to the current shuffle-dwell gamma irradiator. Note that the claim is based primarily on an analytical calculation. Experimental and manufacturing among other practical considerations will be taken into account in the future work to exhaustively evaluate the performance of the proposed configuration and to compare it with that of the traditional configuration.

• Journal of Pharmaceutical Investigation
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• v.31 no.4
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• pp.209-216
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• 2001

The purpose of the present study was to investigate the hepatic uptake and biliary excretion of l-anilino-8-naphthalene sulfonate (ANS) in vivo. The plasma concentration and liver concentration of ANS were determined after its i.v. bolus administration at a dose of $30\;{\mu}mol/kg$ in rats. The hepatic uptake clearance $(CL_{uptake})$ of ANS was 0.1 ml/min/g liver. On the basis of the unbound concentration of ANS, the permeability-surface area product $(PS_{influx})$ was calculated to be l0.4 ml/min/g liver, being comparable of in vitro data. On the other hand, we determined the plasma concentration, liver concentration and biliary excretion rate of ANS at steady-state after its i. v. infusion $(0.2-1.6\;{\mu}mol/min/kg)$ in rats. The excretion clearance $(CL_{excretion})$ of ANS showed Michaelis-Menten kinetics with increasing the infusion rate. The permeability-surface area product $(PS_{excretion})$ based on the unbound concentration in the liver was calculated to be 0.0165 ml/min/g liver, which is negligible compared with the intrinsic clearance $(CL_{int}=3.3\;ml/min/g\;liver)$ by rat liver microsomes. The sequestration process of ANS, therefore, was considered to be mainly due to the metabolic process in the liver $(PS_{seq}{\risingdotseq}CL_{int})$. Furthermore, $PS_{efflux}$ value calculated from $PS_{influx}$ and $PS_{seq}$ was 4.4 ml/min/g liver, which was comparable of in vitro data. In conclusion, in vivo parameters such as $PS_{influx}$, $PS_{efflux}$ and $PS_{seq}$ in the present study showed good in vivo-in vitro relationship. Thus, the kinetic analysis method proposed in the present study would be useful to analyze the hepatic transport of drugs in vivo.

• The Journal of the Korea Contents Association
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• v.12 no.3
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• pp.244-250
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• 2012

The results of analyzing the difference between performances of individual dosimeters on this research subjecting the PLD and TLD, which are the official personal dosimeters, through dosimetry are as follows. After scanning the integral dose using an automatic scanner, the values of two devices that went through dose adjustment process had a statistical difference in TLD and PLD measurements under each filming conditions which were 70kVp, 200mA, 0.012sec and 42kVp, 100mA, and 0.012sec (p<0.001 and p<0.001 respectively). As for the difference of measurement value between DAP and the two particles under 70kVp, 200mA, 0.012sec filming condition, TLD had a value lower than DAP average value by $44.2mGy{\cdot}cm^2$ and PLD had a value of $246.8mGy{\cdot}cm^2$ which was lower than DAP average value by $15.5mGy{\cdot}cm^2$, while under 42kVp, 100mA, 0.012sec filming condition, TLD had a value lower than DAP average value by $17.9mGy{\cdot}cm^2$ and PLD had a value of $82.6mGy{\cdot}cm^2$ which was lower than DAP average value by 7.6$mGy{\cdot}cm^2$. Also, compared to PLD, each of 10 devices measured dose value in TLD had a larger deviation between the particles, and for a reproducibility test which repeatedly measured one particle, PLD had ${\pm}1%$ which was lower than TLD's ${\pm}2%$. As such, PLD had a superior performance result in dose measurement capacities aspect compared to TLD, and therefore we could verify that PLD is more appropriate and advantageous in managing radiation-related task performing worker's personal radiation exposure management in the diagnostic radiation field.

• Journal of radiological science and technology
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• v.39 no.3
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• pp.407-414
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• 2016

This study is to minimize the patient dose and maintain the image quality according to change of source to image receptor distance and applying additional filter. In this study, we used the DR system, the tissue-equivalent abdomen phantom and the aluminium filter. The exposure conditions were set to 80 kVp using AEC mode. The collimation size was $16{\times}16inch$. The exposure dose were measured 10 times when the SID was changed with 100, 110, 120 and 130 cm, respectively. The pirana 657 for dosimeter was located on center of radiation irradiation. The acquired images were analyzed by using the image J. In the results, the tube current was increased with increasing the SID but ESD was decreased with increasing the SID. The decrease of ESD attribute to use of filter that remove the photon of lower energy. In the histogram results using image J, there were differences between the ESD and the exposure conditions according to change of SID. However, there were not differences in histogram. Therefore, the exposure dose could reduced when set the longer SID. For pediatric exam, the exposure dose could reduced when used the aluminium filter.

• Journal of Pharmaceutical Investigation
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• v.33 no.1
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• pp.51-53
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• 2003

This study was conducted to compare the bioavailability of a generic product of Sinil Atenolol Tablets (Sinil Pharmaceutical Co., Ltd., Korea) with the innovator product, $Tenormin^{\circledR}$ Tablets in 20 healthy Korean volunteers. The volunteers received a single 50 mg dose of each atenolol formulation according to a randomized, two-way crossover design. Plasma samples were obtained over a 24-hour interval, and atenolol concentrations were determined by HPLC with a fluorescence detector. From the plasma atenolol concentration vs time curves, the following parameters were compared: area under the plasma concentration-time curve (AUC), peak plasma concentration $(C_{max})$, time to reach peak plasma concentration $(T_{max})$, and terminal first order elimination half-life $(t_{1/2})$. No statistically significant difference was obtained between the $T_{max}$ values, and the logarithmic transformed AUC and $C_{max}$ values of the two products. The 90% confidence for the ratio of the logarithmically transformed AUC and $C_{max}$ values of Sinil Atenolol Tablets over those of $Tenormin^{\circledR}$ Tablets were calculated to be between 0.99 and 1.07, and 1.04 and 1.16, respectively; both were within the bioequivalence limit of 0.80-1.25. The mean of $T_{max}$ in $Tenormin^{\circledR}$ Tablet group was 3.68 hour, and that in Sinil Atenolol Tablet group was 3.65 hour. The values of $t_{1/2}$ between the two products were found comparable, and the mean $t_{1/2}$ values of $Tenormin^{\circledR}$ Tablets and Sinil Atenolol Tablets were 5.9 and 6.0 hour, respectively. Based on these results, it was concluded that Sinil Atenolol Tablets were comparable to $Tenormin^{\circledR}$ Tablets in both the rate and extent of absorption, indicating that Sinil Atenolol Tablets were bioequivalent to the reference product, $Tenormin^{\circledR}$ Tablets

• Biomolecules & Therapeutics
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• v.15 no.3
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• pp.187-191
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• 2007

This study was conducted to compare the bioavailability of two brands of atenolol (50 mg) tablets, which are a generic product of $Ditent^{\circledR}$ (Daewon Pharmaceutical Co., Ltd., Korea) and an innovator product $Tenormin^{\circledR}$ (Hyundai Pharm. Ind. Co., Ltd., Korea), in 20 healthy Korean male volunteers. The volunteers received a single 50 mg dose of each atenolol formulation according to a randomized, two-way cross-over design. The washout period between treatments was 1 week. Plasma samples were obtained over a 24-hour interval, and atenolol concentrations were determined by HPLC with a fluorescence detector. From the plasma atenolol concentration vs. time curves, the following parameters were compared: area under the plasma concentration-time curve ($AUC_{0-24}$), peak plasma concentration ($C_{max}$), time to reach peak plasma concentration ($T_{max}$), and terminal first order elimination half-life ($t_{1/2}$). No statistically significant difference was obtained between the $T_{max}$ values, and the logarithmic transformed $AUC_{0-24}$ and $C_{max}$ values of the two products. The 90% confidence interval for the ratio of the logarithmically transformed AUC and $C_{max}$ values of $Ditent^{\circledR}$ over those of $Tenormin^{\circledR}$ were calculated to be between 0.85 and 1.04, and 0.89 and 1.07, respectively; both were within the bioequivalence limit of 0.80-1.25. The mean of $T_{max}$ in $Tenormin^{\circledR}$ group was 3.1 hour, and that in Ditent$^{\circledR}$ group was 3.2 hour. The values of $t_{1/2}$ between the two products were found comparable, and the mean values were 5.2 hour in the both products. Based on these results, it was concluded that $Ditent^{\circledR}$ was comparable to $Tenormin^{\circledR}$ in both the rate and extent of absorption, indicating that $Ditent^{\circledR}$ was bioequivalent to the reference product, $Tenormin^{\circledR}$.

• Mass Spectrometry Letters
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• v.12 no.1
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• pp.16-20
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• 2021

We aimed to compare the content of ginsenosides and the pharmacokinetics after the oral administration of four different ginseng products at a dose of 1 g/kg in rats. The four different ginseng products were fresh ginseng extract, red ginseng extract, white ginseng extract, and saponin enriched white ginseng extract prepared from the radix of Panax ginseng C.A. Meyer. The ginsenoside concentrations in the ginseng product and the rat plasma samples were determined using a liquid chromatography-tandem mass spectrometry (LC-MS/MS). Eight or nine ginsenosides of the 15 tested ginsenosides were detected; however, the content and total ginsenosides varied depending on the preparation method. Moreover, the content of triglycosylated ginsenosides was higher than that of diglycosylated ginsenosides, and deglycosylated ginsenosides were not present in any preparation. After the single oral administrations of four different ginseng products in rats, only four ginsenosides, such as 20(S)-ginsenosides Rb1 (GRb1), GRb2, GRc, and GRd, were detected in the rat plasma samples among the 15 ginsenosides tested. The plasma concentrations of GRb1, GRb2, GRc, and GRd were different depends on the preparation method but pharmacokinetic features of the four ginseng products were similar. In conclusion, a good correlation between the area under the concentration curve and the content of GRb1, GRb2, and GRc, but not GRd, in the ginseng products was identified and it might be the result of their higher content and intestinal biotransformation of the ginseng product.

• Journal of radiological science and technology
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• v.35 no.4
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• pp.299-308
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• 2012

To perform patient dose surveys in major interventional radiography procedures as a mean of inter-institutional comparison and of establishing reference dose levels with the ultimate goal of optimizing patient doses in the field of interventional radiography. We reviewed international patient dose survey data in the literature and measured patient dose in major interventional radiography procedures (TACE, AVF, PTBD, TFCA, GDC embolization). ESD(Entrance Skin Dose) was measured using TLD chips attached to the patient skin and ED(Effective Dose) was calculated using angiography unit-derived DAP. A survey of patient dose in interventional radiography procedures were also performed with a questionnaire for interventional radiologists and we proposed a guideline for optimizing patient doses in the field of interventional radiology. The patient dose survey data in interventional radiography procedures were very rare in literature compared with those in diagnostic radiography procedures. In TACE, the mean ED was 25.43 mSv and the mean ESD was 511.75 mGy. The mean ED of TACE was not high, but the cumulative dose should be checked, due to longer procedure TACE. In TFCA, the mean ED was 22.6 mSv and it was relatively high compared with data of other countries. In GDC embolization, the mean ED was not available, because GDC embolization was performed with old Image-Intensifier-type unit and there has no unit-installed ionization chamber. Also, the mean ESD of GDC embolization was up to 2,264 mGy and further studies are needed to calculate the net ED of GDC embolization. Patient dose occurred during interventional radiography procedures are high related with the difficulty of the procedure, fluoroscopy time, the number of angiographies and the treatment protocol. Therefore, continuous education and efforts should be made to optimize the patient dose in the field of interventional radiology.

• Journal of the Korean Society of Radiology
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• v.12 no.7
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• pp.845-852
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• 2018

This study aimed to investigate the difference of X-ray exposure by comparing and analyzing absorbed dose according to changes in the number of frames in coronary angiography, also depending whether the zoom mode is FOV enlargement or Zoom Live. Moreover, for appropriate frame selection measures for examination, including the effect of frame change on the image quality, were sought by measuring the noise strength expressed by the standard deviation (SD), the signal to noise ratio (SNR) and contrast to noise ratio (CNR). The study was conducted with an anthropomorphic phantom on an angio-system. The linear relationship between the frame rate and the radiation dose was evident. On the contrary, the indices of image quality (SD, SNR, and CNR) were almost constant irrespective of the number of frames. The difference depending on the zoom mode was not statistically significant for DAP, air kerma, and SD (p > 0.05). However, SNR and CNR were statistically different between FOV enlargement and Zoom Live. In conclusion, since the image quality was not degraded significantly with the decreasing frame rate from 30, 15, to 7.5 f/s and the radiation dose evidently decreases in almost exactly linear proportion to the decreasing frame rate, the number of frames per second needs to be maintained as low as reasonably achievable. As for the dependence on the zooming mode, the Live Zoom mode showed statistically significant improvement in the image quality indices of SNR and CNR and it justifies active use of the Live Zoom mode which enables real-time image enlargment without additional radiation dose.

• Journal of the Korean Society of Radiology
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• v.17 no.4
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• pp.551-556
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• 2023

Angiography equipment is used to evaluate and treat coronary artery disease. As a common feature of equipment, radiation is used, and function development for dose reduction is being carried out by each company. Therefore, the difference depending on whether DCR installed in angiography equipment is used is analyzed from a radiological point of view to prove the effect. Among 431 patients who underwent coronary artery intervention from March 2021 to February 2023, 250 patients with retrospective data were selected. And than among the 250 subjects obtained, 91 patients used the cardiovascular roadmap function during single-vessel intervention, and 159 patients did not use the roadmap. When DCR was used, total dose area product (34.57 uGy/m² : 69.15 uGy/m²), total air kerma dose (688.47 mGy : 1640.4 mGy), fluoroscopy dose (23.87 uGy/m² : 49.91 uGy/m²) and fluoroscopy time (723.55 s : 366.03 s), total number of images (17 : 26) showed lower values and were statistically significant than those not used. The use of DCR function in single vessel coronary intervention is thought to be radiologically safer as single vessel coronary intervention using dynamic cardiovascular DCR showed lower perspective time and perspective dose than procedures performed without the DCR.