• Title/Summary/Keyword: half-dose

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Pharmacokinetics of a New Antigastritic Agent, Eupatilin, an Active Component of StillenE®, in Rats

  • Jang, Ji-Myun;Park, Kyung-Jin;Kim, Dong-Goo;Shim, Hyun-Joo;Ahn, Byung-Ok;Kim, Soon-Hoe;Kim, Won-Bae
    • Biomolecules & Therapeutics
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    • v.11 no.3
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    • pp.163-168
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    • 2003
  • Pharmacokinetics of eupatilin (an active components of $Stillen^{\circledR}$, a new antigastritic agent) were investigated after both intravenous and oral administration at a dose of 30mg/kg to rats. After intravenous administration, the plasma concentrations of unchanged eupatilin declined rapidly with a mean terminal half-life of 0.101 h. Eupatilin was eliminated fast in rats; the total body clearance was 121 mL/min/kg. Eupatilin was mainly metabolized in rats; the percentage of intravenous dose of eupatilin excreted in 24 h urine and feces as unchanged eupatilin was only 2.5 and 0.919%, respectively. Eupatilin was mainly metabolized to form its glucuronide conjugate; after intravenous administration, 15.9 and 51.7% of intravenous dose was excreted in 24 h urine and feces, respectively, as eupatilin plus its glucuronide. After oral administration, the absolute bioavailability was only 3.86% based on $AUC_{0-24h}$ of eupatilin plus its glucuronide. Approximately 68.5% of oral dose was not absorbed from the entire gastrointestinal tract. Therefore, it could be concluded that the superior effect of eupatilin in experimental animal models of gastric ulcer and inflammatory bowel disease after oral administration could be due to the local action of eupatilin. Further pharmacokinetic studies to elucidate the local action of eupatilin are required.

A Study of Radiation Dose and Quality by Using Added Filtration in Chest Radiography (흉부(胸部) X선촬영시(線撮影時) 부가여과사용(附加濾過使用)에 따른 선양(線量)과 선질(線質)에 관(關)한 연구(硏究))

  • You, Byung-Hun;Chu, Sung-Sil;Huh, Joon
    • Journal of radiological science and technology
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    • v.10 no.1
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    • pp.13-23
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    • 1987
  • Author has studied for finding the method of decreasing the radiation dose and increasing diagnostic range in chest X-ray radiography. The study for the added filter thickness from half value layer to 1/8 value layer by decreasing curve and research for the exposure factors, decreasing ratio of radiation dose, ratio of scatter ray and image quality in chest X-ray radiography. The results were as follows: 1. By using the rare earth intensifying screen system at 120 Kvp, the sensitivity is increased by times and the exposure ratio is decreased 0.22 by comparison with the $CaWO_{4}$ intensifying screen system at 80 Kvp. 2. By using Al added filter of 1/8 value layer, the scatter ray is increased more than no filter, But the scatter ray is decreased more in $G_{4}/RxOG$ intensifying system than in LT-II/Rx intensifying system. 3. At 120 Kvp, the image quality value of $G_{4}/RxOG$ system is increased more than LT-II/Rx system compared with slight decreasing image quality value at 80 Kvp. Concluded that by using the added filter could decrease the radiation dose by 1/3 and obtain effective image quality with the added filter at high voltage hard exposure.

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Immunobiological Studies in Mice Treated with Chemical Carcinogen, 3-Methylcholanthrene : II. Rosette Formation and Natural Killing (NK) Activity of Splenic Lymphocytes (발암제(發癌劑) 3-Methylcholanthrene 투여(投與)마우스에 대(對)한 면역생물학적(免疫生物學的) 연구(硏究) : II. 비장세포(脾臟細胞)의 Rosette형성능(形成能) 및 NK세포(細胞)의 활성(活性))

  • Song, Hee-jong;Kim, Sang-ho;Kim, Jong-myeon
    • Korean Journal of Veterinary Research
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    • v.26 no.1
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    • pp.117-124
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    • 1986
  • The present study was undertaken to evaluate rosette formation and NK activity of splenic lymphocytes in 3-methylcholanthrene (MCA) treated mice. Mice were sensitized iv with 0.1ml of 1% sheep red blood cell (SRBC) suspension were treated with a single ip injection of olive oil alone or with different doses of MCA in oil at various time before or after sensitization, and were challenged at 4 days after SRBC. Rosette formation and NK activity of splenic lymphocytes were measured at 24 hours after challenge. Erythrocyte(E) rosette formation of splenic lymphocytes was significantly depressed in mouse treated with large dose of MCA (5~50mg) regardless of injecting time. But, there was no difference in the response between the treated with small dose of MCA (0.5mg). Whereas erythrocyte-antibody(EA) rosette or erythrocyte-antibody-complement(EAC) rosette forming cells were significantly depressed by MCA. Under small dose of MCA (0.5mg), any difference of NK activity was not observed in all course of injecting time. But, under large dose of MCA, the activity was markedly inhibited to about half the values seen in control and this suppression was transient, resulting that the normal level was reached again 19 days after MCA. These results, which conform with the predictions of immunosuppression hypothesis, suggest that MCA inhibits immunological responses including NK activity and thereby allows the outgrowth of antigenic neoplastic cells.

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A Study on the Cytotoxicity of Lead in Cultured Fibroblasts (납(Pb)이 배양 섬유모세포에 미치는 세포독성에 관한 연구)

  • 정연태;최민규;김정중;문연자;김재민;백순기
    • Environmental Mutagens and Carcinogens
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    • v.15 no.2
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    • pp.122-130
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    • 1995
  • In order to evaluate the cytotoxicity of lead in cultures of Balb/c mouse 3T3 cell line, various cytotoxic assays were carried out after expose cells to various concentrations of lead nitrate. Cytotoxic assays using this study were included NR assay, MTT assay, measurement of LDH and protein, synthetic rate of DNA and UDS. Intrace!!ular Ca$^{2+}$ level was also measured. Light and electron microscopic studies were done for morphological changes of lead-treated cell cultures. The results were as follows; 1. The absorbances of NR and MTT were decreased dose-dependently, and NR, and MTT, values of lead nitrate were 3.4 mM and 1.5 mM, respectively. 2. Amount of LDH released into the medium was increased in dose-dependently and LDH activity at 5 mM concentration of lead nitrate was increased to 335 % of control. 3. Amount of total protein was decreased dose-dependently, and which was half of control at 2 mM concentration of lead nitrate. 4. The synthetic rate of DNA was decreased dose-dependently, and also which was remarkably decreased at 3 mM and 5 mM concentrations of lead nitrate. 5. The synthetic rate of UDS was increased at 1 mM concentration of lead nitrate, but which was remarkably decreased at 3 mM and 5 mM concentrations of lead nitrate. 6. Intrace!lular Ca$^{2+}$ level was remarkably increased at 1 mM concentration of lead nitrate, compared with control. 7. In light microscopy, number of cells and processes were decreased according to the increase of dosage of lead nitrate. Electron microscopic findings showed that many vacuoles and cisternal dilatation of rough endoplasmic reticulum were seen in the cytoplasm at 1 mM concentration of lead nittale. From the above results, high dosage treatment of lead nitrate (>3 mM) damaged genetic malerials and it also showed cytotoxicity in mouse 3T3 cell line cultures by injury of cell organelles and Ca$^{2+}$ channel.

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Implantation of an Intrathecal Drug Administration System -A report of two cases- (척수강 내 약물 주입기의 이식 -증례보고-)

  • Lee, Sang Jin;Nam, Sang Kun;Kim, Jang Hyun;Kim, Hyun Joo;Lee, Sang Chul;Kim, Yong Chul
    • The Korean Journal of Pain
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    • v.22 no.1
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    • pp.68-73
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    • 2009
  • Opioids profoundly inhibit evoked discharges of spinal nociceptive neurons, thereby inhibiting the transmission of pain. Intrathecal administration of opioids using implantable continuous infusion systems is an effective method of pain relief when other treatments have failed, as well as for patients with adequate analgesia on high dose therapy that produces unacceptable side effects. We report two cases of intrathecal pump implantation performed in patients suffering from intractable chronic pain. A test dose of 3 mg morphine was injected into the epidural space. No side effects were noted and patients experienced considerable pain relief. Implantation was performed one day after the test. The initial intrathecal morphine delivery dose was half of the equivalent dose of daily oral intake opioids and the infusion rate was increased gradually under close observation for opioid side effects. Two days post-implantation, both patients were discharged without any complications.

Different Distribution of the ${alpha}_{2},Na^+,K^+-ATPase lsoform between Rat Atria and Ventricles$

  • Lee, Jeung-Soo;Lee, Shin-Woong;Wallick, Earl-T
    • Archives of Pharmacal Research
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    • v.19 no.5
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    • pp.381-385
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    • 1996
  • Rat ventricles respond with a biphasic positive inotropic effect to ouabain, low-dose and high-dose effects but rat atria with only a monophasic high dose effect. In an effect to understand the difference in response to ouabain of two tissues between rat atria and ventricles the levels of the $a_{2}$ -isoform of the $Na^{+}$, $K^{+}$-ATPase which has higher affinity for ouabain than the $a_{1}$-iso-form were determined by a $[^{3}H]$ouabain binding assay. The yield of protein per gram wet weight was about 47 mg for atria and 100 mg for ventricles. The $K_{d}$ values of ouabain for the high-affinity ouabain binding site $(a_{2} -isoform)$ were nearly the same (230 nM) in the atria and ventricles. However, the numbers of the $a_{2}$-isoform $(B_{max})$ per mg protein were approximately half in the atria. When the binding data were expressed in unit per gram tissue wet weight, the numbers of $a_{2}$ -isoform in the atria was about 25% of that in the ventricles. THese results demonstrate that the $a_{2}$ -isoform of the $Na^{+}$, $K^{+}$-ATPase in the rat atria could be detected by $[^{3}H]$ouabain binding assay and the levels of this isoform are too low to show the low-dose effect of ouabain.

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Pharmacokinetic Study of CKD-602, A New Camptothecin Derivative: Absorption (신규 캄토테신계 항암제 CKD-602의 약물동태: 흡수)

  • Lee, Ju-Mong;Sohn, Yong-Sung;Kim, Joon-Kyum;Shin, Hee-Jong;Lee, Hyung-Ki;Lee, Sang-Joon;Hong, Chung Il
    • YAKHAK HOEJI
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    • v.42 no.4
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    • pp.431-436
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    • 1998
  • The pharmacokinetics of CKD-602, a new camptothecin anticancer derivative, were studied in mice, rats and dogs following a single or multiple intravenous administration, and the following results were obtained. The blood levels of CKD-602 declined in biphasic fashions with peak plasma levels $(C_0)$ of $2.63{\mu}g/ml$ in mice, $2.27{\mu}g/ml$ in tumor bearing mice, $2.84{\mu}g/ml$ in rats at a dose of 20mg/kg, and of 0.02mcg/ml in dogs at a dose of 0.5mg/kg. The plasma half-lives $(t_{1/2}{\beta})$ were 9.55hr in mice, 9.94hr in tumor bearing mice, 9.98hr in rats and 12.75hr in dogs. AUC of CKD-602 was increased linearly with the dose at a range from 5 to 20mg/kg. Moreover, Cltot and Vdss were also not significantly changed with increasing the dose. On the other hand, after 5 daily intravenous bolus injection of CKD-602 (5mg/kg) in rats, $t_{1/2}{\beta}$, AUC and MRT of CKD-602 were 11.90hr, $3.19{\mu}g{\cdot}hr/ml$, and 11.61hr, respectively, which were slightly higher than after the single bolus injection.

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Evaluation of the Lens-absorbed Dose of the Scattered Radiation Generated During Tomotherapy IMRT to the H&N Cancer Patient

  • Choi, Jae-Won;Lee, Hae-Kag;Cho, Jae-Hwan;Choi, Cheon Woong;Ju, Myung Sik;Chang, Bok Soon;Park, Cheol-Soo
    • Journal of Magnetics
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    • v.22 no.1
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    • pp.141-145
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    • 2017
  • This paper uses a glass dosimeter to evaluate the lens-absorbed dose of scattered radiation generated in tomotherapy intensity modulated radiation therapy (IMRT). The head and neck portion of the rando phantom was subjected to a CT scan. The tomotherapy plan was designed to ensure delivery of the prescribed total 70 Gy day 2.2 Gy. With the lens portion of the glass dosimeter, a 5mm bolus was subjected to the scattered radiation treatment, and the dose was measured in each of the three megavoltage CT (MVCT) modes. The result is multiplied by 30 times and was determined once as the mean value. The measurement at the MVCT Coarse mode is RT mode 10.797 mGy, that for the Normal mode is 13.360 mGy, for the Fine mode is a maximum of 22.872 mGy, and for the treatment mode is 895.830 mGy. A small amount of scattered radiation in the MVCT is measured in the lens scattered radiation, but scattered radiation during treatment was measured to be near 1 Gy on the lens. Compared to a one-time radiation treatment of 2.2 Gy, the survey showed something unexpected in that it was half the value of that research to the patient. Therefore, will be aware of how much of an influence there will be on sensitive organs, such as the lens by scattered radiation generated during intensity modulated radiation therapy.

Pharmacokinetics of oxytetracycline in olive flounder (Paralichthys olivaceus) by dipping and oral administration (Oxytetracycline의 약욕 및 경구투여에 따른 넙치(Paralichthys olivaceus) 체내 약물동태학적 특성)

  • Jung, Sung-Hee;Choi, Dong-Lim;Kim, Jin-Woo;Jo, Mi-Ra;Seo, Jung-Soo;Jee, Bo-Young
    • Journal of fish pathology
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    • v.21 no.2
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    • pp.107-117
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    • 2008
  • The pharmacokinetic properties of oxytetracycline (OTC) were studied after dipping and oral administration to cultured olive flounder, Paralichthys olivaceus (600 g). Plasma concentrations of OTC were determined after oral dosage (50, 100 and 200 mg/kg body weight) and dipping (50, 100 and 200 ppm, 1 h) in olive flounder (average 600 g, 23±1℃). Plasma samples were taken at 3, 5, 10, 15, 24, 32, 48, 72, 120, 168 and 240 h post-dose. In oral dosage of 50, 100 and 200 mg/kg, the peak plasma concentrations of OTC, which attained at 3 h post-dose, were 0.34, 0.44 and 1.18 ㎍/㎖, respectively. In dipping of 50, 100 and 200 ppm, those of OTC which also observed at 5 h post-dose, were 0.43, 0.38 and 0.64 ㎍/㎖, respectively. Plasma concentrations of OTC were not measurable at 240 h post-dose in all experiments. The kinetic profile of absorption, distribution and elimination of OTC in plasma were analyzed fitting to a one-compartment model by WinNonlin program. The following parameters were calculated for a single dosage of 50, 100 and 200 mg/kg body weight, respectively: AUC (the area under the concentration-time curve)=31.40, 28.07 and 32.97 ㎍∙h/㎖; T1/2 (half-life)􀆫0.89, 1.12 and 0.43 h; Tmax (time for maximum concentration)= 5.25, 3.70 and 7.30 h, Cmax (maximum concentration)=0.25, 0.38 and 0.61 ㎕/㎖. Following dipping at 50, 100 and 200 ppm, these parameters were AUC􀆫15.51, 14.63 and 19.72 ㎍∙h/㎖; T1/2= 0.75, 0.41 and 0.74 h; Tmax=4.90, 7.08 and 4.68 h, Cmax=0.40, 0.32 and 0.46 ㎕/㎖.

Detection Limit of a NaI(Tl) Survey Meter to Measure 131I Accumulation in Thyroid Glands of Children after a Nuclear Power Plant Accident

  • Takahiro Kitajima;Michiaki Kai
    • Journal of Radiation Protection and Research
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    • v.48 no.3
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    • pp.131-143
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    • 2023
  • Background: This study examined the detection limit of thyroid screening monitoring conducted at the time of the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident in 2011 using a Monte Carlo simulation. Materials and Methods: We calculated the detection limit of a NaI(Tl) survey meter to measure 131I accumulation in the thyroid gland of children. Mathematical phantoms of 1- and 5-year-old children were developed in the simulation of the Particle and Heavy Ion Transport code System code. Contamination of the body surface with eight radionuclides found after the FDNPP accident was assumed to have been deposited on the neck and shoulder area. Results and Discussion: The detection limit was calculated as a function of ambient dose rate. In the case of 40 Bq/cm2 contamination on the body surface of the neck, the present simulations showed that residual thyroid radioactivity corresponding to thyroid dose of 100 mSv can be detected within 21 days after intake at the ambient dose rate of 0.2 µSv/hr and within 11 days in the case of 2.0 µSv/hr. When a time constant of 10 seconds was used at the dose rate of 0.2 µSv/hr, the estimated survey meter output error was 5%. Evaluation of the effect of individual differences in the location of the thyroid gland confirmed that the measured value would decrease by approximately 6% for a height difference of ±1 cm and increase by approximately 65% for a depth of 1 cm. Conclusion: In the event of a nuclear disaster, simple measurements carried out using a NaI(Tl) scintillation survey meter remain effective for assessing 131I intake. However, it should be noted that the presence of short-half-life radioactive materials on the body surface affects the detection limit.