• Title/Summary/Keyword: Dose dependence

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Effect of Ouabain on the Interaction of Mitochondria with Calcium (Mitochondria의 Calcium Uptake에 미치는 Ouabain의 영향)

  • Hong, Sa-Ack;Park, Chan-Woong;Kim, Myung-Suk;Chung, Myung-Hee
    • The Korean Journal of Pharmacology
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    • v.8 no.1
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    • pp.67-75
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    • 1972
  • Many studies on the mechanism of the inotropic action of cardiac glycosides have shown the possible intimate relationship between the mobilization of intracellular calcium and inotropic effect. Evidence obtained from recent studies suggests that cardiac glycosides may increase the intracellular $Ca^{++}$ concentration through the release of this ion from cellular or intracellular membrane. It seemed imperative to study the effect of ouabain on the interaction between mitochondria and $Ca^{++}$, because mitochondria are known to have a rather powerful $Ca^{++}$ pump mechanism which may have an important role on the regulation of intracellular $Ca^{++}$ concentration. The present investigations was made into the effect of ouabain on $Ca^{++}$ untake of mitochondria in the presence of ATP and its dependence on $K^+$ and $Na^+$ in the medium. The results are summarized as follows: 1. The rate of rise in the turbidity of superprecipitation was solely influenced by ionic strength of the medium, not by the species of ion, i.e. $Na^+$ or $K^+$. The higher ionic strength suppressed and the lower enhanced the rate of superprecipitation respectively. 2. No effect of ouabain was found on the rate of superprecipitation. 3. Mitochondria depressed the rate of superpretipitation, and the depressed rate of superprecipitation by mitochondria was reversed by ouabain, and the degree of this reversal was almost identical in $Na^+$ and $K^+$ medium. 4. $Ca^{++}$ uptake of mitochondria was inhibited by ouabain in the presence of ATP and the degree of inhibition showed the dose-response manner in terms of concentration of ouabain. 5. In the absence of ATP, mitochondria took or the $Ca^{++}$ in initial period but released it later. Such uptake and release of $Ca^{++}$ was not influenced by ouabain. 6. It is suggested that intracellular calcium mobilization by ouabain through the action upon the mitochondria was due to inhibition on ATP-dependent $Ca^{++}$ uptake by this agent, not to the action upon so called binding.

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Resistance to ACCase Inhibitor Cyhalofop-butyl in Echinochloa oryzicola Collected in Gyeongsangnam-do Province of Korea (ACCase 저해 제초제 cyhalofop-butyl에 대한 경남지방 수집종 피의 저항성)

  • Won, Jong Chan;Won, Ok Jae;Ha, Jun;Im, Il-Bin;Kang, Kwang Sik;Pyon, Jong Yeong;Park, Kee Woong;Lee, Jeung Joo
    • Weed & Turfgrass Science
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    • v.7 no.2
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    • pp.166-169
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    • 2018
  • Repeated use of ACCase inhibiting herbicides for a long time has resulted in increases of resistant Echinochloa oryzicola populations in paddy fields in middle west area of Korea. This study aims to investigate current status of herbicide resistant E. oryzicola in Gyeongsangnam-do, in which there is less information about herbicide resistance. For resistance frequency and dose-response study, seeds from 100 individual plants of E. oryzicola in Gyeongsangnam-do were collected and tested with cyhalofop-butyl. Seven percent of plants from Gyeongsangnam-do was resistant at a recommended rate of cyhalofop-butyl. $GR_{50}$ values (herbicide rates required to reduce plant growth 50%) for one representative resistant populations and five susceptible populations were $738g\;a.i.\;ha^{-1}$ and 66-234 (average 147)$g\;a.i.\;ha^{-1}$, respectively, indicating average 5 times difference in resistance. Although lower rate of frequency of herbicide resistance in Gyeongsangnam-do than in Jeollabuk-do, increases of herbicide resistance are expected in this area because of increases of direct seeded rice fields and increases of dependence on a specific herbicide. Therefore, it is necessary to monitor herbicide resistance regularly and conduct integrated herbicide resistance management in this area.

The Steroid Sparing Effects of Cheongsangboha-tang in Asthmatic Patients (청상보하탕(淸上補下湯)의 기관지천식환자에 대한 스테로이드 절약효과)

  • Choi Jun-Yong;Lee Jae-Sung;Ju Chang-Yeop;Jung Hee-Jae;Rhee Hyung-Koo;Jung Sung-Ki;Hwang Woo-Suck
    • The Journal of Internal Korean Medicine
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    • v.24 no.1
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    • pp.1-10
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    • 2003
  • Background : In recent years, the glucocorticoid hormone has become a fundamental medication for asthma. However, a long period of hormone administration will result. in general. side effects on many body parts as well as hormone dependence, which has become a serious problem for western physicians. Objectives : We aimed to identify the clinical effects of Cheongsanghoha-tang and the steroid sparing effects of Cheongsanghoha-tang on. Materials and Methods : A subject group consists of 36 asthmatics who had been treated with Cheongsanghoha-tang for four weeks. Cheongsanghoha-tang is a herbal decoction, which has been used of the traditional therapeutic agent of asthma. PFT, QLQAKA, blood eosinophil, serum IgE, Serum IL-4. IL-5, IFN-${\gamma}$ were checked before and 4weeks after the treatment. Results : The only FVC% in ICSG among asthmatic patients was increased significantly compared to NICSG. Treatment of Cheongsanghoha-tang for four weeks resulted in significant increase in QLQAKA. The NICSG treated with Cheongsangboha-tang for four weeks were no significant difference in the blood eosinophil, serum IgE, IL-4 and IL-5. The PFT and QLQAKA in NICSG were increased significantly after 4 weeks treatment. But the serum IFN-${\gamma}$ in NICSG was decreased significantly after 4 weeks treatment. Discontinuation of treatment with inhaled corticosteroid in ICSG resulted in insignificant changes in PFT, the blood eosinophil, the serum IgE, IL-4, IL-5 and IFN-${\gamma}$ and significant increase in QLQAKA. As a result. 8 of 13 cases were cured with hormones completely and the rest of ICSG reduced the dose of ICS. Conclusions : This study shows that Cheongsanghoha-tang has the effects on the improvement of pulmonary function and cures asthmatic patients. These findings demonstrate that Cheongsanghoha-tang has the steroid sparing effect. Some satisfactory therapeutic results have been obtained in treating hormone-dependent asthma by Cheongsanghoha-tang. However. the concept and mechanism of hormone-dependent asthma have not been fully defined yet, and the standard for judging therapeutic effects have not been established. Obviously further researches concerning all these are still necessary.

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Effects of Sorbed Surfactant on the Surfactant-Enhanced Removal of Hydrophobic Organic Contaminants (토양에 흡착된 계면활성제가 유기오염물 제거에 미치는 영향)

  • 고석오;유희찬
    • Journal of Korea Soil Environment Society
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    • v.4 no.2
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    • pp.77-86
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    • 1999
  • Partitioning of two hydrophobic organic compounds (HOCs), phenanthrene and naphthalene, to kaolinite and sorbed surfactants was studied to evaluate the feasibility of surfactant-enhanced remediation (SER) of contaminated subsurface systems. Sorbed surfactant partition coefficients. $K_ss$, showed a strong dependence on the surfactant sorption isotherms at low sorbed surfactant levels $K_ss$ values were at their highest and then decreased with increasing surfactant sorption densities. $K_ss$ values for SDS were always larger than corresponding $K_mic$values. For Tween 80, however. $K_ss$ values $K_mic$ were higher than $K_mic$ values only at the lower sorbed surfactant densities. HOC distribution between immobile and mobile phases varied with surfactant dose distribution coefficients increased initially with increasing surfactant concentrations and then decreased at higher doses. This observation shows directly the competition between sorbed and micellar surfactants for HOC partitioning. Overall results of this study demonstrate that surfactant sorption to the solid phase can lead to increases in HOC retardation in some SER applications. Therefore, before an SER process is selected, appropriate consideration of surfactant sorption and HOC partitioning to immobile versus mobile phases pertinent to a specific subsurface system must be contemplated.

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The Effect of Injinchunggantang-derivative on Proliferation of Hepatocyte (인진청간탕가미방(茵蔯淸肝湯加味方)이 간세포(肝細胞)의 증식능력(增殖能力)에 미치는 영향(影響))

  • Park, Yong-Jin;Kim, Young-Chul;Lee, Jang-Hoon;Woo, Hong-Jung
    • The Journal of Korean Medicine
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    • v.19 no.1
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    • pp.145-164
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    • 1998
  • The purpose of this study is to evaluate the effect of Injinchunggantang-derivative on proliferation of hepatocyte in rats. Cell viability is studied by MTI assay. The gene related to cell replication such as p53, waf1, bcl-2 and $bcl-_{X_L}$ is quantitized by quantitative RT-PCR and the proteins coded by these genes are studied by Western blotting. The results are as follows. 1. The hepatocytes cultured in medium with lnjinchunggantang-derivative showed better viability compared with control grroup in MTI assay, and the hepatocytes cultured in medium with the Injinchunggantang-derivative-and-ethanol-mixed group showed better viability than the hepatocytes cultrued in 10% ethanol culture medium(control group), noting that Injinchunggantang-derivative has protective effect on hepatocyte injury. There was no dose- and time-dependence. 2. In quantitative RT-PCR, i) Bel-2 gene increased significantly both in Injinchunggantang-derivative group and in Injinchunggantang-derivative-and-ethanol-mixed group, while it showed no significant increase or decrease in other group. ii) $Bcl-_{X_L}$ gene increased significantly in Injinchunggantang-derivative group as well as in Injinchunggantang-deri vative-and-ethanol -mixed group. iii) P53 gene showed no significant increase or decrease in hepatocytes cultured in medium with 10% ethanol and in hepatocytes cultured in medium with Injinchunggantang-derivative-and-ethanol-mixed group, suggesting that 10% ethanol induced cell toxicity, thus increased p53 gene expression. iv) Wafl gene showed no significant increase or decrease in hepatocytes cutured in medium with Injinchtrnggantang-derivative, while increased in hepatocytes cultured in medium with 10% ethanol and in hepatocytes cultured in medium with Injinchtrnggantang-derivative-andethanol-mixed group, suggesting that 10% ethanol induced cell toxicity increased wafl gene expression. 3. In the study on protein by western blotting, the band of bcl-2 and $bcl-_{X_L}$ were widened in Injinchtrnggantang-derivative group. Especially the amount of $bcl-_{X_L}$ increased significantly compared with other groups. But in the study on p53 and wafl, there was no significant difference among those groups. Above study shows that Injinchunggantang-derivative has good effect on cell viability and that the genes resistant to cell death such as bcl-2 and $bcl-_{X_L}$ are induced by Injinchunggantang-derivative to resist to cell death by toxic agent And this is reconfirmed in protein study using' western blotting: These results suggest that Injinchunggantang-derivative has inhibitory effect on cell death as well as protective effect on hepatocyte. Therefore this prescription is recommended in various liver diseases such as chronic liver disease and-induced hepatic injury.

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Protein Composition and Biological Activities of Bombus ignitus Venom (호박벌 일벌독의 성분 분석 및 생리활성 탐색)

  • Han, Sang-Mi;Lee, Kwang-Gill;Yeo, Joo-Hong;Kweon, Hae-Yong;Woo, Soon-Ok;Yoon, Hyung-Joo;Kim, Me-Ae;Kim, Won-Tae;Baek, Ha-Ju
    • Korean journal of applied entomology
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    • v.46 no.2
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    • pp.229-234
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    • 2007
  • Pure Bombus ignitus venom samples were submitted to two-dimensional gel electrophoresis. A total of 64 excised spots were analyzed by mass spectrometry. Three main proteins resulted in the identification have not been described in other bee venoms before. Dose-dependence against human carcinoma (Hep3B, BT-20, A549 and AGS) were observed from 1ng/ml to 100ng/ml. Expecially, the treatment of 100ng/ml B. ignitus venoms showed the highest cytotoxicity with 55% against hepatocellular carcinoma (Hep3B). The B. ignitus venoms showed strong antimicrobial activities against Enterococcus faecium and Shigella sonnei, and practically antimicrobial activity against the other microorganisms tested. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of E. faecium and S. sonnei, were 0.256ug/ml, respectively.

Performance Evaluation of Lead (II) Oxide Dosimeter for Digital Quality Assurance in Brachytherapy (방사선 근접치료의 디지털 정도관리를 위한 Lead (II) Oxide 선량계 성능 평가)

  • Han, Moo-Jae;Yang, Seung-Woo;Park, Sung-Kwang
    • Journal of the Korean Society of Radiology
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    • v.15 no.4
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    • pp.429-435
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    • 2021
  • In intracavitary radiotherapy, incorrect location of the source can cause excessive dose to normal tissue, so it is essential to evaluate the location accuracy of the source. In this study, basic research was performed on digital line dosimeter based on lead (II) oxide (PbO) to improve analog verification method. Therefore, a polycrystalline PbO unit cell dosimeter was manufactured and the measurement performance for Ir-192 sources was evaluated. As a result, the reproducibility satisfies the evaluation criteria of 1.5% with a relative standard deviation of 0.85%. Linearity showed excellent results with a linear coefficient of R2 of 0.9998. In the case of distance dependence evaluation, the power function R2 showed 0.9855 for PbO and 0.9974 for diode, and the overall average difference was 1.66% for PbO and 2.18% for diode. This study presents the basic detection performance of the polycrystalline PbO dosimeter for the Ir-192 source and can provide basic data in the field of radiation measurement.

Fabrication and Evaluation of Mercury(II) Iodide Unit Cell Dosimeter to Confirm the Feasibility of Digital Quality Assurance in Intracavitary Radiotherapy (방사선 근접치료의 디지털 정도관리 가능성 확인을 위한 HgI2 Unit Cell 선량계의 제작 및 평가)

  • Jung, Jae-Hoon;Park, Sung-Kwang
    • Journal of the Korean Society of Radiology
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    • v.16 no.3
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    • pp.257-263
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    • 2022
  • In intracavitary radiotherapy, it is essential to verify the correct location of radiation source among quality control items because an incorrect location will irradiate an unnecessary dose to normal tissues. As a basic study of digital line dosimeters, this study fabricated a unit cell dosimeter based on polycrystalline mercury (II) iodide (HgI2) and compared its performance with a diode. The study result showed that for reproducibility, the relative standard deviation (RSD) was 1.21%, satisfying the RSD evaluation criterion of within 1.5%. Considering linearity, the coefficient of determination R2 showed an excellent result of 0.9997. Regarding the evaluation of distance dependence, it showed a similar trend in general with a difference of 0.035 cm for intensity 50% when compared with the inverse square value. This study suggests the applicability of a digital dosimeter for brachytherapy quality control by evaluating the performance of the HgI2 dosimeter. This study on dosimeter for candidate photoconductor materials can be used as basic data in all areas using radiation.

Physical Characteristics Comparison of Virtual Wedge Device with Physical Wedge (가상쐐기와 기존쐐기의 물리적 특성 비교)

  • Choi Dong-Rak;Shin Kyung Hwan;Lee Kyu Chan;Kim Dae Yong;Ahn Yong Chan;Lim Do Hoon;Kim Moon Kyun;Huh Seung Jae
    • Radiation Oncology Journal
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    • v.17 no.1
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    • pp.78-83
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    • 1999
  • Purpose : We have compared the characteristics of Siemens virtual wedge device with physical wedges for clinical application. Materials and Methods : We investigated the characteristics of virtual and physical wedges for various wedge angles (15, 30, 45, and 60$^{\circ}$) using 6- and 15MV photon beams. Wedge factors were measured in water using an ion chamber for various field sizes and depths. In case of virtual wedge device, as upper jaw moves during irradiation, wedge angles were estimated by accumulated doses. These measurements were performed at off-axis points perpendicular to the beam central axis in water for a 15cm${\times}$20cm radiation field size at the depth of loom. Surface doses without and with virtual or physical wedges were measured using a parallel plate ion chamber at surface. Field size was 15cm H20cm and a polystyrene phantom was used. Results : For various field sizes, virtual and physical wedge factors were changed by maximum 2.1% and 3.9%) , respectively. For various depths, virtual and physical wedge factors were changed by maximum 1.9% and 2.9%, respectively. No major difference was found between the virtual and physical wedge angles and the difference was within 0.5$^{\circ}$ . Suface dose with physical wedge was reduced by maximum 20% (x-ray beam :6 MV, wedge angle:45$^{\circ}$, 550: 80 cm) relative to one with virtual wedge or without wedge. Conclusions : Comparison of the characteristics of Siemens virtual wedge device with physical wedges was performed. Depth dependence of virtual wedge factor was smaller than that of physical wedge factor. Virtual and physical wedge factors were nearly independent of field sizes. The accuracy of virtual and physical wedge angles was excellent. Surface dose was found to be reduced using physical wedge.

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Induction of Autophagy by Low Dose of Cisplatin in H460 Lung Cancer Cells (폐암세포주에서 저용량 시스플라틴에 의해 유도된 자가포식)

  • Shin, Jeong-Hyun;Jang, Hye-Yeon;Chung, Jin-Soo;Cho, Kyung-Hwa;Hwang, Ki-Eun;Kim, So-Young;Kim, Hui-Jung;Lee, Sam-Youn;Lee, Mi-Kung;Park, Soon-Ah;Moon, Sun-Rock;Lee, Kang-Kyu;Jo, Hyang-Jeong;Yang, Sei-Hoon
    • Tuberculosis and Respiratory Diseases
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    • v.69 no.1
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    • pp.16-23
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    • 2010
  • Background: Most lung cancer patients receive systemic chemotherapy at an advanced stage disease. Cisplatin-based chemotherapy is the main regimen for treating advanced lung cancer. Recently, autophagy has become an important mechanism of cellular adaptation under starvation or cell oxidative stress. The purpose of this study was to determine whether or not autophagy can occurred in cisplatin-treated lung cancer cells. Methods: H460 cells were incubated with RPMI 1640 and treated in $5{\mu}M$ or $20{\mu}M$ cisplatin concentrations at specific time intervals. Cells surviving cisplatin treatment were measured and compared using an MTT cell viability assay to cells that underwent apoptosis with autophagy by nuclear staining, apoptotic or autophagic related proteins, and autophagic vacuoles. The development of acidic vascular organelles was using acridine orange staining and fluorescent expression of GFP-LC3 protein in its transfected cells was observed to evaluate autophagy. Results: Lung cancer cells treated with $5{\mu}M$ cisplatin-treated were less sensitive to cell death than $20{\mu}M$ cisplatin-treated cells in a time-dependent manner. Nuclear fragmentation at $5{\mu}M$ was not detected, even though it was discovered at $20{\mu}M$. Poly (ADP-ribose) polymerase cleavages were not detected in $5{\mu}M$ within 24 hours. Massive vacuolization in the cytoplasm of $5{\mu}M$ treated cells were observed. Acridine orange stain-positive cells was increased according in time-dependence manner. The autophagosome-incorporated LC3 II protein expression was increased in $5{\mu}M$ treated cells, but was not detected in $20{\mu}M$ treated cells. The expression of GFP-LC3 were increased in $5{\mu}M$ treated cells in a time-dependent manner. Conclusion: The induction of autophagy occurred in $5{\mu}M$ dose of cisplatin-treated lung cancer cells.