• Title/Summary/Keyword: Internal dose

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Fabrication and Dosimetry Characteristics of Intracavitary Cones for Radiotherapy (방사선 강내치료를 위한 소조사면 전자선cone의 선량분포 특성)

  • 나수경;권수일
    • Progress in Medical Physics
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    • v.12 no.1
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    • pp.95-102
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    • 2001
  • The intracavitary cones were designed which were made of stainless steel and have scratched inside cone to be generated electron scatter and designed to be attached easily to the LINAC collimator and controlled cones length to be contacted smoothly between the patient and the cone tip. Two types of intracavitary cones were designed. One is the straight end cones with circular opening on the distal end and the other is 30 degree beveled end cones with elliptical opening on the distal end. Each type of intracavitary cone ranged in daimeter from 2.5 cm to 3.5 cm and required a separate set of lower trimmer annulias cone diameter. The film phantom was designed with an internal cassette that accurately aligned the film edge with the film phantom surface. Film optical density data were measured by photodensitometer(Wellhofer 700i) Dosimetry measurements were made to commission the LINAC for 6 - 20 MeV electron using the intracavitary cones. Isodose curves were measured for all energy and cones combinations. Output is defined as the maximum dose per MU along the clinical central axis in water at 113 cm SSD. Calibration output, defined to be the output for the 15cm$\times$15cm diameter straight cone, was adjusted to 1.00 cGy/MU at each energy according to the TG-21 protocol.

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The metabolic syndrome and body composition in childhood cancer survivors

  • Sohn, Young-Bae;Kim, Su-Jin;Park, Sung-Won;Kim, Se-Hwa;Cho, Sung-Yoon;Lee, Soo-Hyun;Yoo, Keon-Hee;Sung, Ki-Woong;Chung, Jae-Hoon;Koo, Hong-Hoe;Jin, Dong-Kyu
    • Clinical and Experimental Pediatrics
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    • v.54 no.6
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    • pp.253-259
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    • 2011
  • Purpose: Long-term survivors of childhood cancer appear to have an increased risk for the metabolic syndrome, subsequent type 2 diabetes and cardiovascular disease in adulthood compared to healthy children. The purpose of this study was to investigate the frequency of the metabolic syndrome and associated factors in childhood cancer survivors at a single center in Korea. Methods: We performed a retrospective review of medical records of 98 childhood cancer survivors who were diagnosed and completed anticancer treatment at Samsung Medical Center, Seoul, Korea between Jan. 1996 and Dec. 2007. Parameters of metabolic syndrome were evaluated between Jan. 2008 and Dec. 2009. Clinical and biochemical findings including body fat percentage were analyzed. Results: A total of 19 (19.4%) patients had the metabolic syndrome. The median body fat percentage was 31.5%. The body mass index and waist circumference were positively correlated with the cranial irradiation dose (r=0.38, P<0.001 and r=0.44, P<0.00, respectively). Sixty-one (62.2%) patients had at least one abnormal lipid value. The triglyceride showed significant positive correlation with the body fat percentage (r=0.26, P=0.03). The high density lipoprotein cholesterol showed significant negative correlation with the percent body fat (r=- 0.26, P=0.03). Conclusion: Childhood cancer survivors should have thorough metabolic evaluation including measurement of body fat percentage even if they are not obese. A better understanding of the determinants of the metabolic syndrome during adolescence might provide preventive interventions for improving health outcomes in adulthood.

Influence of Staurosporine on Catecholamine Release Evoked by Cholinergic Stimulation and Membrane Depolarization from the Rat Adrenal Gland

  • Lim, Dong-Yoon;Choi, Yeon-Soo;Yang, Won-Ho;Lee, Yong-Kyoon;Lim, Yong;Choi, Cheol-Hee;Yu, Byung-Sik
    • The Korean Journal of Physiology and Pharmacology
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    • v.4 no.2
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    • pp.149-158
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    • 2000
  • The present study was attempted to examine the effect of staurosporine (STS) on secretion of catecholamines (CA) evoked by cholinergic stimulation and membrane depolarization from the isolated perfused rat adrenal gland and to establish its mechanism of action. The perfusion of STS $(3{\times}10^{-7}{\sim}3{\times}10^{-8}\;M)$ into an adrenal vein for 20 min produced a dose-dependent inhibition in CA secretion evoked by ACh $(5.32{\times}10^{-3}\;M),$ high $K^+\;(5.6{\times}10^{-2}\;M),$ DMPP $(10^{-4}\;M\;for\;2\;min),$ McN-A-343 $(10^{-4}\;M\;for\;2\;min),$ cyclopiazonic acid $(10^{-5}\;M\;for\;4\;min)$ and Bay-K-8644 $(10^{-5}\;M\;for\;4\;min).$ Also, in the presence of tamoxifen $(2{\times}10^{-6}\;M),$ which is known to be a protein kinase inhibitor, CA secretory responses evoked by ACh, high $K^+,$ DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid were also significantly depressed. However, in adrenal glands preloaded with STS $(10^{-7}\;M)$ under the presence of phorbol-12, 13-dibutyrate $(10^{-7}\;M),$ a specific activator of protein kinases (for 20 min), the inhibitory effect of STS on CA secretory responses evoked by ACh, high $K^+,$ DMPP, McN-A-343, Bay-K-8644 and cyclopiazonic acid was greatly recovered to the extent of the control release as compared to those in the presence of STS only. These results demonstrate that STS causes the marked inhibition of CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors as well as by membrane depolarization, indicating strongly that this effect may be mediated by inhibiting influx of extracellular calcium and release in intracellular calcium in the rat adrenomedullary chromaffin cells through preventing activation of protein kinases. Furthermore, these findings also suggest that these STS-sensitive protein kinases play a modulatory role partly in regulating the rat adrenomedullary CA secretion.

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Influence of Ketamine on Catecholamine Secretion in the Perfused Rat Adrenal Medulla

  • Ko, Young-Yeob;Jeong, Yong-Hoon;Lim, Dong-Yoon
    • The Korean Journal of Physiology and Pharmacology
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    • v.12 no.3
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    • pp.101-109
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    • 2008
  • The aim of the present study was to examine the effects of ketamine, a dissociative anesthetics, on secretion of catecholamines (CA) secretion evoked by cholinergic stimulation from the perfused model of the isolated rat adrenal gland, and to establish its mechanism of action, and to compare ketamine effect with that of thiopental sodium, which is one of intravenous barbiturate anesthetics. Ketamine ($30{\sim}300{\mu}M$), perfused into an adrenal vein for 60 min, dose- and time-dependently inhibited the CA secretory responses evoked by ACh (5.32 mM), high $K^+$ (a direct membrane-depolarizer, 56 mM), DMPP (a selective neuronal nicotinic NN receptor agonist, $100{\mu}M$) and McN-A-343 (a selective muscarinic M1 receptor agonist, $100{\mu}M$). Also, in the presence of ketamine ($100{\mu}M$), the CA secretory responses evoked by veratridine (a voltage-dependent $Na^+$ channel activator, $100{\mu}M$), Bay-K-8644 (an L-type dihydropyridine $Ca^{2+}$ channel activator, $10{\mu}M$), and cyclopiazonic acid (a cytoplasmic $Ca^{2+}$-ATPase inhibitor, $10{\mu}M$) were significantly reduced, respectively. Interestingly, thiopental sodium ($100{\mu}M$) also caused the inhibitory effects on the CA secretory responses evoked by ACh, high $K^+$, DMPP, McN-A-343, veratridine, Bay-K-8644, and cyclopiazonic acid. Collectively, these experimental results demonstrate that ketamine inhibits the CA secretion evoked by stimulation of cholinergic (both nicotinic and muscarinic) receptors and the membrane depolarization from the isolated perfused rat adrenal gland. It seems likely that the inhibitory effect of ketamine is mediated by blocking the influx of both $Ca^{2+}$ and $Na^+$ through voltage-dependent $Ca^{2+}$ and $Na^+$ channels into the rat adrenal medullary chromaffin cells as well as by inhibiting $Ca^{2+}$ release from the cytoplasmic calcium store, which are relevant to the blockade of cholinergic receptors. It is also thought that, on the basis of concentrations, ketamine causes similar inhibitory effect with thiopental in the CA secretion from the perfused rat adrenal medulla.

Bee-Venom Acupuncture Treatment of Hip Osteoarthritis in a Dog (개에서 둔부 골관절염의 봉침 치료)

  • Kim Tae-Hwa;Kim Byung-Young;Kim Won-Bae;Kim Kwang-Shik;Liu Jianzhu;Kim Duck-Hwan;Rogers Phil A.M.
    • Journal of Veterinary Clinics
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    • v.23 no.2
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    • pp.190-193
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    • 2006
  • Two weeks of therapy with intra-articular hyaluronic acid and oral caprofen failed to improve the clinical signs of hip osteoarthritis radiologically confirmed in a dog. Then, over the period of 30 days (7 sessions at 5-day intervals), bee- venom acupuncture (BV-AP, injection of bee venom at acupoints, also called apitoxin-aquapuncture) plus Trigger Point (TP) therapy was used. Five acupoints on the affected right limb were injected each time: GB30(as local point), plus ST35, GB33, BL40 and LIV08 (as distant points). The injection mixture (0.2 ml/point; total 1 ml/session) was saline + apitoxin + 2% lidocaine, so that the injected solution contained $100{\mu}g$ apitoxin diluted in 0.2% lidocaine-saline solution/ml. The total dose of apitoxin used was, therefore, $100{\mu}g/session$, divided over the 5 acupoints. One TP in the middle of the right quadriceps muscle was injected with 2% lidocaine (0.2 ml/point) each time. BV-AP improved the clinical signs rapidly; lameness and ataxia were disappear after 7 sessions (30 days); the right hind limb muscular atrophy was much improved and the hip radiograph was almost normal two weeks after 7 sessions (44 days). The present patient was a case with canine hip osteoarthritis which showed favorable therapeutic response by BV-AP plus TP therapy.

Inflammation Scan Using $^{99m}Tc-HMPAO$ Labelled Leukocytes ($^{99m}Tc-HMPAO$를 이용한 자가백혈구표지 및 그를 이용한 염증병소의 스캔)

  • Yang, Woo-Jin;Chung, Soo-Kyo;Shinn, Kyung-Sub;Bahk, Yong-Whee;Kim, Hoon-Kyo
    • The Korean Journal of Nuclear Medicine
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    • v.23 no.2
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    • pp.219-223
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    • 1989
  • Inflammation scan using radiolabelled leukocytes has high sensitivity and specificity. Several methods for labelling leukocytes have been evaluated using P-32 diisopropyl fluorophosphate (DFP-32), H-3 thymidine, Cr-51 chromate, Ga-67 citrate and Tc-99m-sulfur colloid. In-111-oxine has proved so far to be the most reliable agent for labelling leukocytes. In-111-oxine is, however, expensive, not easily available when needed, and its radiation dose to leukocytes is relatively high. Moreover, resolution of the resultant image is relatively poor. Tc-99m is still the agent of choice because of, as compared with the indium, its favorable physical characteristics, lower cost and availability. Now the technique for labelling the leukocytes with technetium is successfully obtained using the lipophilic HAPAO with higher efficiency for granulocytes than for other cells. With this technique it is possible to label leukocytes in plasma to improve the viability of the leukocytes. Inflammation scan using Tc-99m-HMPAO has been evaluated in several laboratories, and difference in methods for separation and labelling accounts for difference in efficiency, viability and biodistribution of the labelled leukocytes. We performed inflammation scan using leukocytes labelled with Tc-99m-HMPAO in three dogs 24 hours after inoculation of live E. Coli and A. Aureus in their right abdominal wall. We separated mixed leukocytes by simple sedimentation using 6% hetastarch (HES) and labelled the leukocytes with Tc-99m-HMPAO in 20% cell free plama diluted with phosphate buffer solution(Fig. 1). Uptake was high in the liver and spleen but is was minimal in the lungs on whole body scan. Kidneys and intestine showed minimal activity although it was high in the urinary bladder(Fig. 2). Uptake of labelled leukocytes in the inflammation site was do(mite on 2 hour-postinjection scan and abscess was clearly delineated on 24 hour-delayed scan with high target-to-nontarget ratio(Fig. 3, 4). Inflammation scan using mixed leukocytes labelled with Tc-99m-HMPAO is very sensitive and specific in early detection of inflammation.

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Detection of Irradiated Chicken, Pork and Beef by ESR Spectroscopy (닭고기, 돼지고기 및 쇠고기의 방사선 조사 유무 판별을 위한 ESR Spectroscopy의 활용)

  • Yang, Jae-Seung;Kim, Choong-Ki;Lee, Hae-Jung
    • Korean Journal of Food Science and Technology
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    • v.31 no.3
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    • pp.606-611
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    • 1999
  • To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. Bones cleaned, pieced and dried were irradiated with doses of 0, 1, 3, 5 kGys using a $Co^{60}$ irradiator. The bones were placed in a resonant quartz tube with an internal diameter of about 4.0 mm within the Bruker Win-ESR spectrometer, and the intensity of the ESR signal could be quantified by double integration of the first derivative spectrum. The irradiated bone presented an asymmetric absorption in shape, different from that of an unirradiated one. It could be possible to detect at doses lower than 1 kGy below the dose employed commercially (3 kGy) in the case of irradiated chicken bone. The signal intensity was greatest in the beef bone, intermediate in the pork bone and lowest in the chicken bone; it was normally lower for smaller animals than for larger species, and small variations were observed between samples of the same species. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats.

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Influence of the Monitoring Interval and Intake Pattern for the Evaluation of Intake (내부피폭 감시주기 및 섭취형태가 방사성핵종 섭취량 평가에 미치는 영향)

  • Jong-Il Lee;Tae-Young Lee;Si-Young Chang;Jai-Ki Lee
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.2 no.1
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    • pp.53-59
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    • 2004
  • A variety of factors such as the pattern of intake (acute or chronic), monitoring interval and the characteristics of the radionuclides could have a significant influence on the estimates for the intake and internal dose. The relative differences of the assessed intakes based on the assumption of an acute intake to that of a chronic intake were evaluated by using the predicted bioassay quantity in the whole body or organs for an acute and chronic intake through the inhalation of $^{125}$ I, $^{137}$ C, $^{235}$ U with the AMAD of 1 ${\mu}{\textrm}{m}$ and 5 ${\mu}{\textrm}{m}$ for the monitoring intervals of 7, 14, 30, 60, 90, 120, 180, 360 days, respectively, The relative difference of the assessed intakes based on the intake pattern is affected by the monitoring interval, radionuclide and absorption type, but the particle size has little influence on the difference of the assessed intakes based on the intake pattern. The maximum monitoring interval, which is defined as the monitoring interval that the relative difference of the assessed intakes based on the assumption of an acute intake to that of a chronic intake is less than 10%, is 60 d for $^{125}$ I with Type F, 180 d for $^{137}$ C with Type F, 90 d for $^{235}$ U with Type M, and 360 d for $^{235}$ U with Type S. It was concluded that an intake pattern has little influence on the estimates of the assessed intake in the case where the monitoring interval is shorter than the maximum monitoring interval for each radionuclide.

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Gastrointestinal and Hepatic First-pass Effects of Triflusal in Rats (흰쥐에서 트리플루살의 위장관 및 간 초회통과효과)

  • Cho, Hea-Young;Jeong, Tae-Jin;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.31 no.4
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    • pp.265-271
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    • 2001
  • In order to elucidate the influence of intestinal and hepatic first-pass effect on the pharmacokinetics of triflusal, the biotransformation of triflusal in the gastrointestinal tract and liver was designed. Moreover, we tried to establish an HPLC method applicable for bioassay and available to pharmacokinetics, not only with the simultaneous determination of triflusal and its active metabolite, 2-hydroxy-4-trifluoromethyl benzoic acid (HTB), but also with improving sensitivity. After the administration of triflusal (10 mg/kg) and HTB (10 mg/kg) into femoral vein, portal vein (only triflusal) and oral route (only triflusal), pharmacokinetic parameters were investigated from the plasma concentration-time profiles of triflusal and HTB in rats. An HPLC method was developed for the simultaneous determination of triflusal and HTB in rat plasma, urine and bile. The HPLC analysis was carried out using a C18 column and acetonitrile-methanol-water (25:10:65, v/v/v) as the mobile phase and UV detection at 234 nm. Furosemide was used as the internal standard. The calibration curves were linear over the concentration range $0.05-5.0\;{\mu}g/ml$ for triflusal and $0.2-200.0\;{\mu}g/ml$ for HTB with correlation coefficients greater than 0.999 and with intra-day or inter-day coefficients of variation not exceeding 10.0%. This assay procedure was applied to the study of metabolite pharmacokinetics of triflusal and HTB in rats. It was supposed that triflusal was almost metabolized in vivo because urinary and biliary excreted amounts of triflusal could be ignored as it was lower than 1.2% of the administered dose. According to the gastrointestinal and hepatic biotransformation pathways of triflusal, it was found that triflusal was hydrolyzed by about 5% in intestine and metabolized by about 53% in liver, and that the bioavailability of triflusal after oral administration of triflusal was 0.44, and also that the fraction of total elimination rate of triflusal which formed HTB in liver $(F_{mi},\;%)$ was about 98%. These results showed that triflusal was almost metabolized in liver, and the total elimination of triflusal in the body was dependent to the formation rate of HTB from triflusal in liver.

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Bioequivalence of Samchundang Lercanidipine Tablet 10 mg to Zanidip Tablet (Lercanidipine Hydrochloride 10 mg) by Liquid Chromatography with Tandem Mass Spectrometry

  • Kim, Se-Mi;Kim, Hwan-Ho;Shin, Sae-Byeok;Kang, Hyun-Ah;Cho, Hea-Young;Kim, Yoon-Gyoon;Lee, Yong-Bok
    • Journal of Pharmaceutical Investigation
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    • v.37 no.5
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    • pp.315-321
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    • 2007
  • The purpose of the present study was to evaluate the bioequivalence of two lercanidipine hydrochloride tablets, Zanidip tablet (LG Life Sciences Ltd., Korea, reference drug) and Samchundang Lercanidipine tablet 10 mg (Sam Chun Dang Pharm. Co. Ltd., Korea, test drug), according to the guidelines of Korea Food and Drug Administration (KFDA). After adding an internal standard (amlodipine maleate) to human serum, serum samples were extracted using hexan-isoamyl alcohol (100:1, v/v). Compounds were analyzed by liquid chromatography/tandem mass spectrometry. This method showed linear response over the concentration range of 0.05-20 ng/mL with correlation coefficient of 0.9999. The lower limit of quantitation using 0.5 mL of serum was 0.05 ng/mL which was sensitive enough for pharmacokinetic studies. Thirty healthy male Korean volunteers received each medicine at the lercanidipine hydrochloride dose of 20 mg in a $2\;{\times}\;2$ crossover study. There was a one-week washout period between the doses. Serum concentrations of lercanidipine were monitored by an LC/MS/MS fer over a period of 24 hr after the administration. $AUC_t$ (the area under the serum concentration-time curve from time 0 to 24 hr) was calculated by the linear trapezoidal rule method. $C_{max}$ (the maximum serum drug concentration) and $T_{max}$ (the time to reach $C_{max}$) were compiled from the serum concentration-time data. Analysis of variance was carried out using logarithmically transformed $AUC_t$ and $C_{max}$. No significant sequence effect was found for all of the bioavailability parameters, indicating that the crossover design was properly performed. The 90% confidence intervals of the $AUC_t$ ratio and the $C_{max}$ ratio for Samchundang Lercanidipine/Zanidip were log 0.9505-log 1.2258 and log 0.9987-log 1.2013, respectively. These values were within the acceptable bioequivalence intervals of log 0.80-log 1.25. Thus, the criteria of the KFDA guidelines for the bioequivalence was satisfied, indicating Samchundang Lercanidipine tablet 10 mg and Zanidip tablet are bioequivalent.