• Title/Summary/Keyword: Biomedical application

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Application of the Orally Inserted Guiding Device for the Improved Motion Artifacts of the Cervical Spine MRI (경추부 자기공명영상의 움직임 인공물 개선을 위한 구강내 삽입 유도 기구의 적용)

  • Lee, Jaeheun;Yu, Yunsik;Lee, Jaeseung;Im, Inchul
    • Journal of the Korean Society of Radiology
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    • v.8 no.6
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    • pp.317-323
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    • 2014
  • This study aims to suggest and test methods using an orally inserted guiding device in order to improve a motion artifact by involuntary oral motor such as removing one's dentures and swallowing saliva clinically structured cervical spine scan and to make the optimal image by minimizing motion artifact. A cervical spine test was conducted with 30 patients who wore dentures among those who had a cervical spinal disease from January 1, 2014 through June 30, 2014. As for testing methods, after removing denture, T1-TSE-Sagittal, T2-TSE-Sagittal, T1-TSE-Axial and T2-TSE-Axial were obtained in a normal position and a supine position; the orally inserted guiding device was inserted in patients' mouth; and then T1-TSE-Axial and T2-TSE-Axial were retested. As a result, in SNR, T1-TSE-Axial before inserting an orally inserted guiding device was $22.33{\pm}8.59$; T1-TSE-Axial after inserting the orally inserted guiding device was $25.21{\pm}7.93$; T2-TSE-Axial before inserting the orally inserted guiding device was $14.49{\pm}5.74$; and T2-TSE-Axial after inserting the orally inserted guiding device was $16.61{\pm}6.72$. In CNR, T1-TSE-Axial was measured at $0.23{\pm}0.01$ while T2-TSE-Axial at $0.21{\pm}0.01$. As a result of the qualitative analysis, T1-TSE-Axial before inserting the orally inserted guiding device was $3.49{\pm}0.11$; T1-TSE-Axial after inserting the orally inserted guiding device was $3.95{\pm}0.14$; T2-TSE-Axial before inserting the orally inserted guiding device was $3.25{\pm}0.18$; and T2-TSE-Axial after inserting the orally inserted guiding device was $3.68{\pm}0.09$. As a result of using an orally inserted guiding device, the resolution and contrast of the images improved as the patients' involuntary artifact decreased because of removing dentures and swallowing saliva, and it was found that the interpretation of the images and identification of the diseases improved.

Single- and Repeated-Dose Oral Toxicity in Rats and Bacterial Reverse Mutation Test of Morus alba L. Extracts (상지추출물의 단회/반복투여 독성 및 복귀돌연변이능 평가)

  • Han, Taewon;Um, Min Young;Lim, Young Hee;Kim, Jeong-Keun;Kim, In-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.10
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    • pp.1406-1413
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    • 2016
  • This study was carried out to evaluate the toxicity of ethanolic extracts of Morus alba L. branch (ME). In the reverse mutation test, Salmonella Typhimurium TA98, TA100, TA1535, TA1357, and Escherichia coli WP2uvrA were used to estimate the mutagenic potential of ME. Sprague-Dawley rats were orally administered ME at levels of 1,250, 2,500, and 5,000 mg/kg for the single-dose toxicity test and 500, 1,000, and 2,000 mg/kg/d for the repeated-dose toxicity test for 28 consecutive days. As expected, reverse mutation was not detected at any concentration of ME, regardless of application of the metabolic activation system with or without S9 mix. In the single-dose toxicity test, ME caused neither significant visible signs of toxicity nor mortality in rats, and $LD_{50}$ was estimated to be over 5,000 mg/kg. In the repeated-dose toxicity test, ME administration at 500, 1,000, and 2,000 mg/kg for 28 days to male or female rats did not result in mortality. Similarly, no toxicologically significant treatment-related changes in body weight, food intake, or organ weights were noted. Several hematological and biochemical parameters in both genders showed significant differences, but these were within normal ranges. These results support the safe use of ME.

Evaluation of Geometric Correspondence of kV X-ray Images, Electric Portal Images and Digitally Reconstructed Radiographic Images (kV X선 영상, 전자조사문 영상, 디지털화재구성 영상 간 기하학적 일치성 평가)

  • Cheong, Kwang-Ho;Kim, Kyoung-Joo;Cho, Byung-Chul;Kang, Sei-Kwon;Juh, Ra-Hyeong;Bae, Hoon-Sik;Suh, Tae-Suk
    • Progress in Medical Physics
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    • v.18 no.3
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    • pp.118-125
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    • 2007
  • In this study we estimated a geometric correlation among digitally reconstructed radiographic image (DRRI), kV x-ray image (kVXI) from the On-Board Imager (OBI) and electric portal image (EPI). To verify geometric correspondence of DRRI, kVXI and EPI, specially designed phantom with indexed 6 ball bearings (BBs) were employed. After accurate setup of the phantom on a treatment couch using orthogonal EPIs, we acquired set of orthogonal kVXIs and EPIs then compared the absolute positions of the center of the BBs calculated at each phantom plane for kVXI and EPI respectively. We also checked matching result for obliquely incident beam (gantry angle of $315^{\circ}$) after 2D-2D matching provided by OBI application. A reference EPI obtained after initial setup of the phantom was compared with 10 series of EPIs acquired after each 2D-2D matching. Imaginary setup errors were generated from -5 mm to 5 mm at each couch motion direction. Calculated positions of all center positions of the BBs at three different images were agreed with the actual points within a millimeter and each other. Calculated center positions of the BBs from the reference and obtained EPIs after 2D-2D matching agreed within a millimeter. We could tentatively conclude that the OBI system was mechanically quite reliable for image guided radiation therapy (IGRT) purpose.

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Sequential Pituitary Hormone Responses to Electroconvulsive Therapy (전기경련요법후 뇌하수체 호르몬의 순차적인 분비 반응)

  • Kim, Doh Kwan;Kim, Soo Jeong;Choi, Do Sun;Bok, Hae-Sook;Kim, Seungtai Peter
    • Korean Journal of Biological Psychiatry
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    • v.3 no.2
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    • pp.288-294
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    • 1996
  • Background : Most studies of the pituitary hormonal responses to electroconvulsive therapy(ECT) have used limited blood sampling schedules. Little is known about the precise sequence of neuroendocrine events immediately following en ECT application. or about the regulation of the hormonal responses. Methods : Blood was sampled at three minute intervals from eleven patients(two schizophrenics and nine affective disorder patients) undergoing ECT. Each sample was immunologically assayed for arginine vasopressin(AVP), adrenocorticotropic hormone(ACTH), prolactin(PRL), and cortisol. Baseline hormone concentrations and several measures of response were determined for each hormone. The temporal and quantitative relationships among the hormonal responses were determined. Correlations were calculated between seizure duration and secretory responses. Results : All four hormones demonstrated significant secretory responses to ECT, with AVP increasing from 1.2 to 33.3pg/ml(P<0.001), ACTH from 5.4 to 32.3fmol/ml(P<0001). PRL from 21.8 to 102.2ng/ml(P<0.005) and cortisol from 20.1 to 31.1ug/dl(P<0.001). The three pituitary hormones showed consistent time courses of secretion with onset of responses by three minutes but clearly differing peak times of 3, 6, and 12-15 minutes for AVP, ACTH, and PRL, respectively. Cortisol began to rise after 6minutes and pecked between 20-30minutes. There ware no significant correlations between seizure duration and any of the secretory response measures. Conclusions : 1) The pituitary hormone response to ECT is sequential rather than synchronous 2) The AVP response was extremely rapid and more massive than those of any other hormones. 3) The ACTH response of this study was more rapid and mare robust than thai revealed by the mast of past studies. 4) The results strongly suggest that the pituitary hormones are released as a result of the seizure rather tho, the electrical stimulus. 5) The sequential pattern of responses suggests that neuroendocine feedback-regulatory mechanisms determine the response profile.

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Development of an Automatic Seed Marker Registration Algorithm Using CT and kV X-ray Images (CT 영상 및 kV X선 영상을 이용한 자동 표지 맞춤 알고리듬 개발)

  • Cheong, Kwang-Ho;Cho, Byung-Chul;Kang, Sei-Kwon;Kim, Kyoung-Joo;Bae, Hoon-Sik;Suh, Tae-Suk
    • Radiation Oncology Journal
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    • v.25 no.1
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    • pp.54-61
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    • 2007
  • [ $\underline{Purpose}$ ]: The purpose of this study is to develop a practical method for determining accurate marker positions for prostate cancer radiotherapy using CT images and kV x-ray images obtained from the use of the on- board imager (OBI). $\underline{Materials\;and\;Methods}$: Three gold seed markers were implanted into the reference position inside a prostate gland by a urologist. Multiple digital image processing techniques were used to determine seed marker position and the center-of-mass (COM) technique was employed to determine a representative reference seed marker position. A setup discrepancy can be estimated by comparing a computed $COM_{OBI}$ with the reference $COM_{CT}$. A proposed algorithm was applied to a seed phantom and to four prostate cancer patients with seed implants treated in our clinic. $\underline{Results}$: In the phantom study, the calculated $COM_{CT}$ and $COM_{OBI}$ agreed with $COM_{actual}$ within a millimeter. The algorithm also could localize each seed marker correctly and calculated $COM_{CT}$ and $COM_{OBI}$ for all CT and kV x-ray image sets, respectively. Discrepancies of setup errors between 2D-2D matching results using the OBI application and results using the proposed algorithm were less than one millimeter for each axis. The setup error of each patient was in the range of $0.1{\pm}2.7{\sim}1.8{\pm}6.6\;mm$ in the AP direction, $0.8{\pm}1.6{\sim}2.0{\pm}2.7\;mm$ in the SI direction and $-0.9{\pm}1.5{\sim}2.8{\pm}3.0\;mm$ in the lateral direction, even though the setup error was quite patient dependent. $\underline{Conclusion}$: As it took less than 10 seconds to evaluate a setup discrepancy, it can be helpful to reduce the setup correction time while minimizing subjective factors that may be user dependent. However, the on-line correction process should be integrated into the treatment machine control system for a more reliable procedure.

Clinical Application of in Vivo Dosimetry System in Radiotherapy of Pelvis (골반부 방사선 치료 환자에서 in vivo 선량측정시스템의 임상적용)

  • Kim, Bo-Kyung;Chie, Eui-Kyu;Huh, Soon-Nyung;Lee, Hyoung-Koo;Ha, Sung-Whan
    • Journal of Radiation Protection and Research
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    • v.27 no.1
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    • pp.37-49
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    • 2002
  • The accuracy of radiation dose delivery to target volume is one of the most important factors for good local control and less treatment complication. In vivo dosimetry is an essential QA procedure to confirm the radiation dose delivered to the patients. Transmission dose measurement is a useful method of in vivo dosimetry and it's advantages are non-invasiveness, simplicity and no additional efforts needed for dosimetry. In our department, in vivo dosimetry system using measurement of transmission dose was manufactured and algorithms for estimation of transmission dose were developed and tested with phantom in various conditions successfully. This system was applied in clinic to test stability, reproducibility and applicability to daily treatment and the accuracy of the algorithm. Transmission dose measurement was performed over three weeks. To test the reproducibility of this system, X-tay output was measured before daily treatment and then every hour during treatment time in reference condition(field size; $10 cm{\times} 10 cm$, 100 MU). Data of 11 patients whose pelvis were treated more than three times were analyzed. The reproducibility of the dosimetry system was acceptable with variations of measurement during each day and over 3 week period within ${\pm}2.0%$. On anterior- posterior and posterior fields, mean errors were between -5.20% and +2.20% without bone correction and between -0.62% and +3.32% with bone correction. On right and left lateral fields, mean errors were between -10.80% and +3.46% without bone correction and between -0.55% and +3.50% with bone correction. As the results, we could confirm the reproducibility and stability of our dosimetry system and its applicability in daily radiation treatment. We could also find that inhomogeneity correction for bone is essential and the estimated transmission doses are relatively accurate.

Tissue Engineered Cartilage Formation on Various PLGA Scaffolds (PLGA 종류와 담체의 형성 방법에 따른 인간의 조직공학적 연골형성)

  • 김유미;임종옥;정호윤;박태인;백운이
    • Journal of Biomedical Engineering Research
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    • v.23 no.2
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    • pp.147-153
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    • 2002
  • The purpose of this study was to evacuate the effect of different types of Poly(lactic-co-glycolic acid) (PLGA) scaffolds on the formation of human auricular and septal cartilages. All of the scaffolds were formed in a tubular shape for potential application for artificial trachea or esophagus with either 110,000 g/mol PLGA. 220,000 g/mol PLGA. or a combination of both. In order to maintain the tubular shape in vivo, two methods were used. One method was inserting polyethylene tube at the center of scaffolds made of 110,000 g/mol PLGA. The other method involved combination of the two different molecular weight PLGA's. The inner surface of tubular shaped scaffold made with 110,000 g/mol PLGA was coated with 220,000 9/mol PLGA to give more mechanical rigidity. Elastic cartilage was taken from the ear of a patient aged under 20 nears old and hyaline cartilage was taken from the nasal septum. The chondrocytes were then isolated. After second passage, the chondrocytes were seeded on the PLGA scaffolds followed by in vitro culture for one week. The cells-PLGA scaffold complex were implanted subcutaneously on the back of nude mice for 8 weeks. The tissue engineered cartilages were separated from nude mice and examined histologically after staining with the Hematoxylin Eosin. The morphology of the scaffolds were examined by scanning electron microscopy. The pores were well formed and uniformly distributed in the various PLGA scaffolds. After 8 weeks in vivo culture, cartilage was well formed with 110,000 g/mol PLGA. however lumen had collapsed. In contrast. a minimal amount of neocartilage was formed with 220,000 g/mol PLGA, while the architecture of scaffold and lumen were well preserved. Elastic cartilage formed more neocartilage than hyaline. Hyaline and elastic neocartilage were well formed on 110,000 g/mol PLGA with the polyethylene tube, exhibiting mature chondrocytes and preservation of the tubular shape. It was found that 110,000 g/mol PLGA was more appropriate for cartilage formation but higher molecular weight polymer was necessary to maintain the three dimensional shape of the scaffold.

Influence of Delayed Gastric Emptying in Radiotherapy after a Subtotal Gastrectomy (위부분절제술 후 방사선치료에서 음식물 배출지연에 따른 영향)

  • Kim, Dong-Hyun;Kim, Won-Taek;Lee, Mi-Ran;Ki, Yong-Gan;Nam, Ji-Ho;Park, Dal;Jeon, Ho-Sang;Jeon, Kye-Rok;Kim, Dong-Won
    • Radiation Oncology Journal
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    • v.27 no.4
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    • pp.194-200
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    • 2009
  • Purpose: This aim of this study was to evaluate changes in gastric volume and organ position as a result of delayed gastric emptying after a subtotal gastrectomy performed as part of the treatment of stomach cancer. Materials and Methods: The medical records of 32 patients who underwent concurrent chemoradiotherapy after a subtotal gastrectomy from March 2005 to December 2008 were reviewed. Of these, 5 patients that had more than 50 cc of residual gastric food detected at computed tomography (CT) simulation, were retrospectively enrolled in this study. Gastric volume and organ location was measured from CT images obtained before radiotherapy, twice weekly. In addition, authors evaluated the change of radiation dose distribution to planning the target volume and normal organ in a constant radiation therapy plan regardless of gastric volume variation. Results: A variation in the gastric volume was observed during the radiotherapy period (64.2~340.8 cc; mean, 188.2 cc). According to the change in gastric volume, the location of the left kidney was shifted up to 0.7 - 2.2 cm (mean, 1.2 cm) in the z-axis. Under-dose to planning target volume (V43, 79.5${\pm}$10.4%) and over-dose to left kidney (V20, 34.1${\pm}$12.1%; Mean dose, 23.5${\pm}$8.3 Gy) was expected, given that gastric volume change due to delayed gastric emptying wasn't taken into account. Conclusion: This study has shown that a great change in gastric volume and left kidney location may occur during the radiation therapy period following a subtotal gastrectomy, as a result of delayed gastric emptying. Detection of patients who experienced delayed gastric emptying and the application of gastric volume variation to radiation therapy planning will be very important.

Application of the Pulsatile Cardiopulmonary Bypass in Animal Model (이중 박동성 인공심폐기의 동물 실험)

  • Shin, Hwa-Kyun;Won, Yong-Soon;Lee, Jea-Yook;Her, Keun;Yeum, Yook;Kim, Seung-Chul;Min, Byoung-Goo
    • Journal of Chest Surgery
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    • v.37 no.1
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    • pp.1-10
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    • 2004
  • Background: Currently, the cardiopulmonary machine with non-pulsatile pumps, which are low in internal circuit pressure and cause little damage to blood cells, is widely used. However, a great number of experimental studies shows that pulsatile perfusions are more useful than non-pulsatile counterparts in many areas, such as homodynamic, metabolism, organ functions, and micro-circulation. Yet, many concerns relating to pulsatile cardiopulmonary machines, such as high internal circuit pressure and blood cell damage, have long hindered the development of pulsatile cardiopulmonary machines. Against this backdrop, this study focuses on the safety and effectiveness of the pulsatile cardiopulmonary machines developed by a domestic research lab. Material and Method: The dual-pulsatile cardiopulmonary bypass experiment with total extracorporeal circulation was conducted on six calves, Extracorporeal circulation was provided between superior/inferior vena cava and aorta. The membrane oxygenator, which was placed between the left and right pumps, was used for blood oxygenation. Circulation took four hours. Arterial blood gas analysis and blood tests were also conducted. Plasma hemoglobin levels were calculated, while pulse pressure and internal circuit pressure were carefully observed. Measurement was taken five times; once before the operation of the cardiopulmonary bypass, and after its operation it was taken every hour for four hours. Result: Through the arterial blood gas analysis, PCO2 and pH remained within normal levels. PO2 in arterial blood showed enough oxygenation of over 100 mmHg. The level of plasma hemoglobin, which had total cardiopulmonary circulation, steadily increased to 15.87 $\pm$ 5.63 after four hours passed, but remained below 20 mg/㎗. There was no obvious abnormal findings in blood test. Systolic blood pressure which was at 97.5$\pm$5.7 mmHg during the pre-circulation contraction period, was maintained over 100 mmHg as time passed. Moreover, diastolic blood pressure was 72.2 $\pm$ 7.7 mmHg during the expansion period and well kept at the appropriate level with time passing by. Average blood pressure which was 83$\pm$9.2 mmHg before circulation, increased as time passed, while pump flow was maintained over 3.3 L/min. Blood pressure fluctuation during total extracorporeal circulation showed a similar level of arterial blood pressure of pre-circulation heart. Conclusion: In the experiment mentioned above, pulsatile cardiopulmonary machines using the doual-pulsatile structure provided effective pulsatile blood flow with little damage in blood cells, showing excellence in the aspects of hematology and hemodynamic. Therefore, it is expected that the pulsatile cardiopulmonary machine, if it becomes a standard cardiopulmonary machine in all heart operations, will provide stable blood flow to end-organs.

Fertilizing Effects of Swine Compost Fermented with Sawdust on Mixed Pastures (혼파초지에 대한 톱밥발효돈분의 시용효과)

  • Shin, J. Soon;Cho, Young-Mu;Lee, Hyo-Ho;Yoon, Sea-Hung;Park, Geun-Je;Choi, Ki-Chun
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.24 no.3
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    • pp.245-252
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    • 2004
  • Experiment was carried out to find the fertilizing effects of 8 different application rates of swine compost fermented with sawdust(SCS) including Chemical fertilizer(CF) on forage yield and soil chemical characteristics of mixed pastures sown in Sep. 1993 at National Livestock Research Institute, RDA., in Suwon during low years. It was arranged in a randomized complete block design with three replicates. Dry matter yield were shown at similar among treatments except Control and $50\%$ SCS of standard amount plot. In botanical composition, the legume and weeds percentages of each treatment were increased as advancing year. The final year's legume percentage were high in line with SCS fertilizing plots($39\%{\sim}43\%$), SCS + CF plots($30\%{\sim}41\%$) and CF plot($32\%$). In productions of TDN, NE and crude protein yield, SCS or SCS($75\%$) + CF($25\%$) were nearly same comparing those of CF, respectively. Phosphate, potassium, magnesium contents and K/(Ca + Mg) except calcium contents of those SCS fertilizing plots in plant were generally high with comparing CF. Those contents were proportional according to the fertilizing amount These result indicate the possibility to substitute chemical fertilizer for SCS($75\%$, 25ton/ha) + CF, $25\%$) as manure-N 210 kg/ha, but might be considered accumulation phosphate in the soil.