• Title/Summary/Keyword: STABILITY

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Inhibitory Role of Polyamines in Dexamethasone-induced Apoptosis of Mouse Thymocytes (Dexamethasone에 의한 생쥐 흉선의 Apoptosis에서 Polyamine의 역할)

  • Choi, Sang-Hyun;Kim, Yong-Hoon;Hong, Gi-Hyun;Shin, Kyung-Ho;Chun, Yeon-Sook;Chun, Boe-Gwun
    • The Korean Journal of Pharmacology
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    • v.32 no.1
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    • pp.113-123
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    • 1996
  • It has been well known that polyamines ensure the stability of chromatin structure and the fidelity of DNA transcription. This study was carried out to evaluate the effect of polyamines on the apoptosis of mouse thymocytes induced by dexamethasone and polyamine synthesis inhibitors. 1) In the histological death findings of thymocytes double-stained with acridine orange and ethidium bromide, the apoptotic and the necrotic fractions (AF; NF) in the control group were $9.4{\pm}4.2%$ and $4.5{\pm}5.3%$, respectively. Dexamethasone $(3\;{\times}\;10^{-8}\;M:\;DX)$ in creased AF upto $52.0{\pm}8.1%$ and did not change NF, but A23187 $(5\;{\times}\;10^{-7}\;M:\;A2)$ increased AF and NF upto $45.0{\pm}8.9%$ and $20.5{\pm}10.6%$, respectively. 2) The thymocyte viability was significantly reduced by DX, DHEA $(1\;{\times}\;10^{-4}\;M)$, A2, DFMO $(1\;{\times}\;10^{-4}\;M)$, and $MGBG\;(1\;{\times}\;10^{-4}\;M)$, respectively. It was, however, little affected by $aminoguanidine\;(1\;{\times}\;10^{-4}\;M:\;AG)$, $putrescine\;(1\;{\times}\;10^{-5}\;M:\;PT)$, $spermidine\;(1\;{\times}\;10^{-5}\;M:\;SD)$, and $spermine\;(1\;{\times}\;10^{-5}\;M:\;SM)$. 3) The genomic DNA of mouse thymocyte was markedly fragmented by DX and A2, respectively, and to a lesser extent, by DHEA, but was little affected by MGBG, DFMO, AG, and each of polyamines. 4) The DX induced reduction of thymocyte viability was moderately attenuated by DHEA, but little affected by DFMO, MGBC, and AG. However, SM significantly attenuated the viability reduction induced by A2 as well as DX. 5) The thymocyte viability reduction by MGBG and DFMO was significantly attenuated by only SM among three polyamines applied in this study. 6) The thymocyte viability redution by combined treatments of DX with DFMO and MGBG, respectively, was significantly attenuated by SM, and moderately by PT. But the viability reduction by combined treatment of DX with AG or DHEA was not affected by polyamines. These results suggest that polyamines, particularly spermine, might play the inhibitory role in thymocyte apoptosis and the inhibitory effect can be ascribed in part to the increase of polyamine uptake by thymocytes pretreated with DFMO and MGBG.

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Characteristic Evaluation of Optically Stimulated Luminescent Dosimeter (OSLD) for Dosimetry (광유도발광선량계(Optically Stimulated Luminescent Dosimeter)의 선량 특성에 관한 고찰)

  • Kim, Jeong-Mi;Jeon, Su-Dong;Back, Geum-Mun;Jo, Young-Pil;Yun, Hwa-Ryong;Kwon, Kyung-Tae
    • The Journal of Korean Society for Radiation Therapy
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    • v.22 no.2
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    • pp.123-129
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    • 2010
  • Purpose: The purpose of this study was to evaluate dosimetric characteristics of Optically stimulated luminescent dosimeters (OSLD) for dosimetry Materials and Methods: InLight/OSL $NanoDot^{TM}$ dosimeters was used including $Inlight^{TM}MicroStar$ Reader, Solid Water Phantom, and Linear accelerator ($TRYLOGY^{(R)}$) OSLDs were placed at a Dmax in a solid water phantom and were irradiated with 100 cGy of 6 MV X-rays. Most irradiations were carried out using an SSD set up 100 cm, $10{\times}10\;cm^2$ field and 300 MU/min. The time dependence were measured at 10 minute intervals. The dose dependence were measured from 50 cGy to 600 cGy. The energy dependence was measured for nominal photon beam energies of 6, 15 MV and electron beam energies of 4-20 MeV. The dose rate dependence were also measured for dose rates of 100-1,000 MU/min. Finally, the PDD was measured by OSLDs and Ion-chamber. Results: The reproducibility of OSLD according to the Time flow was evaluated within ${\pm}2.5%$. The result of Linearity of OSLD, the dose was increased linearly up to about the 300 cGy and increased supralinearly above the 300 cGy. Energy and dose rate dependence of the response of OSL detectors were evaluated within ${\pm}2%$ and ${\pm}3%$. $PDD_{10}$ and PDD20 which were measured by OSLD was 66.7%, 38.4% and $PDD_{10}$ and $PDD_{20}$ which were measured by Ion-chamber was 66.6%, 38.3% Conclusion: As a result of analyzing characteration of OSLD, OSLD was evaluated within ${\pm}3%$ according to the change of the time, enregy and dose rate. The $PDD_{10}$ and $PDD_{20}$ are measured by OSLD and ion-chamber were evaluated within 0.3%. The OSL response is linear with a dose in the range 50~300 cGy. It was possible to repeat measurement many times and progress of the measurement of reading is easy. So the stability of the system and linear dose response relationship make it a good for dosimetry.

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The Proprioceptive Function of Rotator Cuff Tear Patients: Preliminary Report of Pre-operative Function (회전근개 파열 환자의 고유 수용성 감각 기능: 수술전 기능의 예비 보고)

  • Lee, Hyunil;Heo, Jaewon;Yoo, Jae Chul
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.12 no.1
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    • pp.29-36
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    • 2013
  • Purpose: Proprioceptive function has been known to be important to shoulder stability. However, the function in rotator cuff tear patients is rarely investigated. The purpose of current study is to report the proprioceptive function in rotator cuff tear patients and to analyze the proprioceptive function regarding the tear size and the presence of subscapularis tear. Materials and Methods: Between 2011 and 2012, total 76 patients (male 28 and female 48) were recruited and average age was 61.7 years old (range, 38~76). Preoperatively, joint position senses in internal and external rotation were measured for proprioceptive function testing by method of active re-positioning technique. The absolute difference from set point was measured. Proprioceptive function was further analyzed according to tear size of rotator cuff, the presence of subscapularis tear, visual analogue scale of pain, shoulder functional score (American society of elbow and shoulder score), and ranges of motion in shoulder. Results: The absolute difference for external rotation was $4.9^{\circ}{\pm}2.9^{\circ}$, in normal joint and $4.9^{\circ}{\pm}3.0^{\circ}$for involved joint in rotator cuff tear patients. This difference was not significant statistically (p=0.87). The absolute difference for internal rotation was $4.0^{\circ}{\pm}2.7^{\circ}$in normal joint whereas $4.8^{\circ}{\pm}3.7^{\circ}$ for involved joint showing statistically significant difference (p=0.043). There was some trend that the proprioceptive function of internal rotation was more impaired in the bigger tear size group (more than medium tear) compared to the smaller tear size group (partial thickness and small tear, 5.0 vs. 4.0, p=0.061). The impairment of internal rotation proprioception was also accentuated in patients with subscapularis tear (4.8 vs. 4.0, p=0.065). The proprioceptive function of internal rotation was decreased when the pain visual analogue scale was increased (5.2 vs. 4.0 p=0.04), shoulder functional score was decreased (6.1 vs. 4.2, p=0.005), or range of motion in shoulder joint was restricted (5.3 vs. 3.7, p=0.041). Conclusion: The deficit of proprioceptive function was observed in rotator cuff tear patients. Proprioception for internal rotation was impaired in patients with the bigger tear size and subscapularis tear. Pain, shoulder function score, and range of motion were also shown to be related with the deficit in proprioceptive function.

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A Retrospective Analysis of the Relationship Between Rotator Cuff Tear and Biceps Lesion (후하방 회전근 개 파열과 상완이두박근 장두건 병변과의 연관 관계에 대한 후향적 분석)

  • Seo, Seung-Suk;Kim, Jung-Han;Choi, Jang-Seok;Kim, Jeon-Gyo
    • Clinics in Shoulder and Elbow
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    • v.14 no.1
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    • pp.13-19
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    • 2011
  • Purpose: Not much is known about the obvious relationship between posteroinferior rotator cuff tear and biceps lesion. The purpose of this study is to analyze the effect of posteroinferior rotator cuff tear on a biceps lesions by comparing the rotator cuff tear and biceps lesions with the number of cuff tears and the degree of degeneration of the rotator cuff. Materials and Methods: 65 patients who underwent surgery for a posteroinferior rotator cuff tear from 2002 to 2009 were included as subjects. The study determined the factors (the number of cuff tears and the degree of degeneration as assessed by MRI) that affected biceps lesions and the kinematic stability of the rotator cuff. Results: Biceps lesion was noted 11 patients among the 51 patients with supraspinatus tendon tears and in 8 patients among the 14 patients with supraspinatus, infraspinatus or teres minor tendon tears, and there was a statistically significant difference between those two groups (p=0.0095). The number of cuff tears was proportional to biceps lesion with statistical significance (p=0.0095). Among the biceps lesions, SLAP II lesion showed a statistically different distribution according to the number of cuff tears (p=0.0073). The degeneration factors (Goutallier's classification and the tangent sign) had no correlations with biceps lesion. Conclusion: Posterosuperior cuff tear may affect biceps lesion. Especially, the number of cuff tears has a close relationship, but the degenerative indicators have no relationship with biceps lesion.

Measurements of Setup Error and Physiological Movement of Liver by Using Electronic Portal Imaging Device in Patients with Hepatocellular Carcinoma (간암환자에서 Electronic Portal Imaging Device(EPID)를 이용한 자세 오차 및 종양 이동 거리의 객관적 측정)

  • Keum Ki Chang;Lee Sang-wook;Shin Hyun Soo;Kim Gwi Eon;Sung Jinsil Seong;Lee Chang Geol;Chu Sung Sil;Chang Sei-Kyung;Suh Chang Ok
    • Radiation Oncology Journal
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    • v.18 no.2
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    • pp.107-113
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    • 2000
  • Purpose : The goal of this study 닌as to improve the accuracy of three-dimensional conformal radiotherapy (3-D CRT) by measuring the treatment setup error and physiological movement of liver based on the analysis of images which were obtained by electronic portal imaging device (EPID). Materials and Methods : For 10 patients with hepatocellular carcinoma, 4-7 portal images were obtained by using EPID during the radiotherapy from each patient daiiy. We analyzed the setup error and physiological movement of liver based on the verification data. We also determined the safety margin of the tumor in 3-D CRT through the analysis of physiological movement. Results : The setup errors were measured as 3mm with standard deviation 1.70 mm in x direction and 3.7 mm with standard deviation 1.88 mm in y direction respectively. Hence, deviation were smaller than 5mm from the center of each axis. The measured range of liver movement due to the physiological motion was 8.63 mm on the average. Considering the motion of liver and setup error, the safety margin of tumor was at least 15 mm. Conclusion : EPID is a very useful device for the determination of the optimal margin of the tumor, and thus enhance the accuracy and stability of the 3-D CRT in patients with hepatocellular carcinoma.

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Study of Environmental Stability of the East Sea by Foraminiferal Distribution (유공충을 이용한 동해의 환경 안정성 연구)

  • Shin, Im-Chul;Yi, Hi-Il
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.3 no.4
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    • pp.234-248
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    • 1998
  • Seven box cores from the disposal areas located in the southern part of the East Sea (Stations Band B') and in the offshore to the east of Pusan (Stations J and J'), and from their surrounding areas (Stations J2, J6 and H) were collected to investigate the effect of dumped wastes on the foraminiferal assemblages. The species diversity indices [S, H(S), E] of foraminifera and the total number of foraminifera show significant differences between the ocean waste disposal areas and their adjacent areas. Ocean waste disposal areas located in southern part of the East Sea (Stations Band B') show not only smaller number of foraminifera species but also lower values of coarse fraction content in the sediment and the number of benthic and planktonic foraminifera than the surrounding areas. Another ocean disposal area located offshore Pusan (Station J') contains abnormally greater number of planktonic (approximately 300 000 individuals/lO g dried sediment) and benthic (approximately 300, 000 individuals/10 g dried sediment) foraminifera compared to those of the adjacent areas. The waste dumped at Station J' probably acts as a nutrient causing the greater number of foraminifera. Station J shows low species diversity indices [S, H(S)]. The number of benthic foraminifera decreases from the surface to the downcore at Station J, which indicates that Station J is under stress. However, Stations J', J2 and J6 are under stable conditions as evidenced by the greater species diversity indices [S, H(S)] compared to other stations. No foraminifera were found with biological disease or abnormal chambers, which commonly occur in extremely stressed environment, in both the ocean disposal and adjacent areas. The organic matter decay of the wastes dumped in the study areas has not made the bottom water corrosive.

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Relationship of Hemodynamic Changes during Off-Pump Coronary Bypass Grafting and Their Effects on Postoperative Outcome (심폐바이패스 없이 시행하는 관상동맥 우회수술 중의 혈역학적 변수들의 변화양상 및 수술 후 결과에 미치는 영향)

  • 허재학;장지민;김욱성;장우익;이윤석;정철현
    • Journal of Chest Surgery
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    • v.36 no.8
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    • pp.576-582
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    • 2003
  • During the Off-Pump Coronary Arterial Bypass surgery (OPCAB), the manipulation of the heart can depress cardiac contractility and cause hemodynamic instability. In this study, hemodynamic parameters were measured during operation and the laboratory and clinical data were investigated to evaluate their effects on postoperative outcome. Material and Method: From March 2001 to August 2002, 50 consecutive patients who underwent OPCAB were included in this study. During the same period, total number of CABG was 71 The blood pressure, pulmonary artery pressure, mixed venous oxygen saturation, and cardiac index were measured before manipulation, after application of stabilizer, and at the end of anastomosis. Postoperatively, we measured the cardiac enzymes such as CK-MB, troponin 1 and checked the amount of inotropes required, chest tube drainage, the amount of transfusion, duration of ventilator support, and duration of ICU stay. Result: The number of mean distal anastomoses was 2.8$\pm$0.9 per patient. On elevation and stabilization of the heart, systolic blood pressure was depressed and pulmonary artery pressure was elevated significantly, but during each anastomosis no significant changes were detected. The peak level of cardiac markers was 29.2$\pm$46.7 for CK-MB, 0.69$\pm$0.86 for troponin 1 on postoperative day f. Among the intraoperative hemodynamic parameters, the ischemic change of EKG and bolus injection of inotropes significantly affected the posteroperative cardiac enzymes. But, no difference other than the level of cardiac enzymes between the two groups with or without the ischemic change of EKG and bolus injection of inotropes was noticed. Conclusion: The significant hemodynamic changes occurred when the heart was elevated and stabilized, however during anastomoses there were no significant changes. Serum cardiac enzymes rose significantly in the group that showed the ischemic charge of EKG or needed the bolus injection of inotropes for maintaining hemodynamic stability intraoperatively, but it did not affect the postoperative outcome. In conclusion, the ischemic change of EKG and the need for bolus injection of intropes during operation may be very indicative for probable ischemia.

Influence of Glass Dielectric Property on the External Electrode Fluorescent Lamps (유리관의 유전 특성이 외부전극 형광램프에 미치는 영향)

  • Shin, Myeong-Ju;Jeong, Jong-Mun;Kim, Jung-Hyun;Kim, Ga-Eul;Lee, Mi-Ran;Yoo, Dong-Gun;Koo, Je-Huan;Hong, Byoung-Hee;Choi, Eun-Ha;Cho, Guang-Sup
    • Journal of the Korean Vacuum Society
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    • v.16 no.5
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    • pp.330-337
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    • 2007
  • Influence of glass dielectric property (dielectric constant K, dielectric loss) on the external electrode fluorescent lamps of the dielectric barrier discharge has been investigated with 4-different glasses. Conventional borosilicate glass tubes with $K=5.6{\sim}5.9$ and tan ${\delta}=5.0{\times}10^{-3}{\sim}6.0{\times}10^{-3}$ and aluminosilicate glass tubes with high K=6.6 and low tan ${\delta}=1{\times}10^{-4}$ and soda-lime glass tribes with K=7.7 and tan ${\delta}=1.37{\times}10^{-2}$ have been compared. The high value of dielectric constant K makes the capacitance of external electrode fluorescent lamps intensity and enhances the discharge efficiency. The dielectric loss of tan ${\delta}$ shows the factor of power consumption in the external electrode to induce heats and to be weak in pinhole stability. The aluminosilicate glass tubes of high K and low tan ${\delta}$ have been enhanced by $14{\sim}18%$ in luminance and efficiency in comparison with the conventional borosilicate glass tubes and the aluminosilicate external electrode fluorescent lamps are strong against the pinhole formation. Soda-lime glass tubes with high K and high tan ${\delta}$ are a little favorable in luminance and efficiency and they are very weak in pinhole occurrence.

Study on Wood-Plastic Combination - On the Penetration of MMA Polymer and Dimensional Stability - (복합목재(複合木材)(WPC)에 관(關)한 연구(硏究) - MMA Polymer의 침투(浸透)와 치수안정화(安定化) -)

  • Lee, Won-Yong
    • Journal of the Korean Wood Science and Technology
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    • v.11 no.3
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    • pp.49-57
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    • 1983
  • This study dealts with the penetration of methyl methacrylate(MMA) monomer-solvent system into five Korean major tree species, especially the Pinus koraiensis S. et Z., Pinus densiflora S. et Z., Larix leptoiepis Gordon, Quercus serrata Thunb. and Betula platyphylla var japonica Hara. In this report I described the results of the interaction between wood and polymer loading by catalyst-heat polymerization. On the other hand the influence of penetration of polymer loading on dimensional stabilization on WPC of Pinus koraiensis by catalyst-heat polymerization was also investigated.

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A Study on the Bonding Strength, Reactivity and Thermal Properties of Epoxy Resin Mixed with ESBO (에폭시수지-ESBO 혼용 비율에 따른 목재접착제의 접착력, 반응성 및 열분석에 관한 연구)

  • Choi, Jin Lim;Park, Heon
    • Journal of the Korean Wood Science and Technology
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    • v.35 no.3
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    • pp.36-44
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    • 2007
  • The purpose of this study was to investigate thermal stability, reactivity, and bonding strength of existing epoxy resin mixed with the epoxidized soybean oil (ESBO) in order to use soybean oil economically. In the dry shear test, the marked strengths showed $30.5kgf/cm^2$ at the ratio of ESBO to epoxy resin 9 : 1 and $6.2kgf/cm^2$ at the ratio 8 : 2. The bonding strengths of the others, except mixing ratios 2 : 8 and 1 : 9, exceeded the requirement of Korean plywood standard of $7.0kgf/cm^2$. In the wet shear test, the result was $5.8kgf/cm^2$ at the ratio 9 : 1. There were no thickness swelling and moisture absorption in the water resistance of the film. The value of activation energy, Tg (${\Delta}E$), by DSC analysis showed between $110^{\circ}C$ and $120^{\circ}C$ through all ratios. Epoxy in the epoxy resin fully reacted with the hardener (TETA), but it is difficult to decide that epoxys in the ESBO were reacted directly with the hardener from FT-IR analysis. As the mixing ratio of ESBO increased, the thermal stabilities dropped from TGA analysis. From the comprehensive view on the results of above experiments, it could be confirmed through experiments that the ESBO in the mixed adhesive of epoxy resin/ESBO played a role as an extending agent level of epoxy adhesive, and we were able to know that in order to utilize ESBO as an adhesive, a study should be performed on the condition of hardening, inducible of the hardening reaction.