• 제목/요약/키워드: Plasma Space

검색결과 456건 처리시간 0.04초

Prediction of Prognosis in Glioblastoma Using Radiomics Features of Dynamic Contrast-Enhanced MRI

  • Elena Pak;Kyu Sung Choi;Seung Hong Choi;Chul-Kee Park;Tae Min Kim;Sung-Hye Park;Joo Ho Lee;Soon-Tae Lee;Inpyeong Hwang;Roh-Eul Yoo;Koung Mi Kang;Tae Jin Yun;Ji-Hoon Kim;Chul-Ho Sohn
    • Korean Journal of Radiology
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    • 제22권9호
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    • pp.1514-1524
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    • 2021
  • Objective: To develop a radiomics risk score based on dynamic contrast-enhanced (DCE) MRI for prognosis prediction in patients with glioblastoma. Materials and Methods: One hundred and fifty patients (92 male [61.3%]; mean age ± standard deviation, 60.5 ± 13.5 years) with glioblastoma who underwent preoperative MRI were enrolled in the study. Six hundred and forty-two radiomic features were extracted from volume transfer constant (Ktrans), fractional volume of vascular plasma space (Vp), and fractional volume of extravascular extracellular space (Ve) maps of DCE MRI, wherein the regions of interest were based on both T1-weighted contrast-enhancing areas and non-enhancing T2 hyperintense areas. Using feature selection algorithms, salient radiomic features were selected from the 642 features. Next, a radiomics risk score was developed using a weighted combination of the selected features in the discovery set (n = 105); the risk score was validated in the validation set (n = 45) by investigating the difference in prognosis between the "radiomics risk score" groups. Finally, multivariable Cox regression analysis for progression-free survival was performed using the radiomics risk score and clinical variables as covariates. Results: 16 radiomic features obtained from non-enhancing T2 hyperintense areas were selected among the 642 features identified. The radiomics risk score was used to stratify high- and low-risk groups in both the discovery and validation sets (both p < 0.001 by the log-rank test). The radiomics risk score and presence of isocitrate dehydrogenase (IDH) mutation showed independent associations with progression-free survival in opposite directions (hazard ratio, 3.56; p = 0.004 and hazard ratio, 0.34; p = 0.022, respectively). Conclusion: We developed and validated the "radiomics risk score" from the features of DCE MRI based on non-enhancing T2 hyperintense areas for risk stratification of patients with glioblastoma. It was associated with progression-free survival independently of IDH mutation status.

Electrically conductive nano adhesive bonding: Futuristic approach for satellites and electromagnetic interference shielding

  • Ganesh, M. Gokul;Lavenya, K.;Kirubashini, K.A.;Ajeesh, G.;Bhowmik, Shantanu;Epaarachchi, Jayantha Ananda;Yuan, Xiaowen
    • Advances in aircraft and spacecraft science
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    • 제4권6호
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    • pp.729-744
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    • 2017
  • This investigation highlights rationale of electrically conductive nano adhesives for its essential application for Electromagnetic Interference (EMI) Shielding in satellites and Lightning Strike Protection in aircrafts. Carbon Nano Fibres (CNF) were functionalized by electroless process using Tollen's reagent and by Plasma Enhanced Chemical Vapour Deposition (PECVD) process by depositing silver on CNF. Different weight percentage of CNF and silver coated CNF were reinforced into the epoxy resin hardener system. Scanning Electron Microscopy (SEM) micrographs clearly show the presence of CNF in the epoxy matrix, thus giving enough evidence to show that dispersion is uniform. Transmission Electron Microscopy (TEM) studies reveal that there is uniform deposition of silver on CNF resulting in significant improvement in interfacial adhesion with epoxy matrix. There is a considerable increase in thermal stability of the conductive nano adhesive demonstrated by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). Four probe conductivity meters clearly shows a substantial increase in the electrical conductivity of silver coated CNF-epoxy composite compared to non-coated CNF-epoxy composite. Tensile test results clearly show that there is a significant increase in the tensile strength of silver coated CNF-composites compared to non-coated CNF-epoxy composites. Consequently, this technology is highly desirable for satellites and EMI Shielding and will open a new dimension in space research.

Attenuation of ROS Generation by KCNE1 Genes in Cisplatin-treated Auditory Cells

  • Kim, Eun Sook;Park, Sang-Ho;Park, Raekil
    • 대한임상검사과학회지
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    • 제45권3호
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    • pp.114-119
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    • 2013
  • Potassium is essential for the proper functioning of the ears. The inner ear's endolymph differs from all other extracellular fluids (in its positive potential) and in the ionic compositions in the various parts of the endolymphatic space. Ion concentration of the endolymph is 150 mM of potassium, which is comparable to the concentrations in other organs. Cisplatin (cis-diamminedichloroplatinum II: CDDP) is one of the most effective anticancer drugs, widely used against various tumors. However, its clinical use is limited by the onset of severe side effects, including ototoxicity and nephrotoxicity. For ototoxicity, a number of evidences in cytotoxic mechanism of cisplatin, including perturbation of redox status, increase in lipid peroxydation, and formation of DNA adduct, have been suggested. Therefore, in this study, the author investigated the relationship between the potassium ions on cisplatin-induced cytotoxicity in HEI-OC1 cells associated with reactive oxygen species (ROS). KCNE1 gene expression by the concentration of intracellular potassium appeared in the plasma membrane and increased the concentration of intracellular potassium. Cisplatin decreased the viability of HEI-OC1 cells, but the KCNE1 gene increased. Also, the KCNE1 gene significantly suppressed generation of intracellular ROS by cisplatin. Western blot analysis showed that the KCNE1 gene increased phase II detoxification enzymes markers such as superoxide dismutase 1 (SOD1), superoxide dismutase (SOD2), NAD(P)H:quinine oxidoreductases (NQO1), which were associated with the scavenger of ROS. These results suggest that the KCNE1 gene for intracellular potassium concentration ultimately prevents ROS generation from cisplatin and further contributes to protect auditory sensory hair cells from ROS produced by cisplatin.

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저밀도 지질단백질 및 산화 LDL(Oxidized-LDL)의 특성 (Function Properties of Low Density Lipoprotein (LDL) and Oxidized-LDL)

  • Tae-Koong Kim
    • 한국식품영양과학회지
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    • 제23권3호
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    • pp.530-539
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    • 1994
  • 최근 지방 섭추의 증가에 따른 혈관계 질병이 증가 추세에 있다. 이러한 동맥경화 및 고지질의 질병은 지질 단백질(lipoprotein)과 관련하여, LDL 및 산화 LDL의 특성을 중심으로 고찰하였다. 인체의 혈장에 함유된 LDL 함량의 증가는, 동맥경화와 직결되는 것을 의미하며, 이러한 LDL은 매우 hydrophobic한 특성을 가진 550Kd의 단일 polypeptide인 Apo B-100라는 단백질이, 지질성분인 triglyceide, phospholipid 및 cholesterol와 결합되어 있다. 최근 이러한 LDL은 산화(oxidation)되는 경우, 정상적인 LDL-receptor pathway를 따르지 않고, macrophang와 결합하므로서, foarn cell을 형성하여 동백경화가 촉진되는 것으로 알려지고 있다.

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혈우병을 가진 어린이의 치과치료 (Dental Treatment of Child with Hemophilia)

  • 임지은;이수언;안효정;박재홍;최성철
    • 대한치과마취과학회지
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    • 제12권4호
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    • pp.229-233
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    • 2012
  • Severe한 혈우병 B 환아가 소아과에 입원하여 세계혈우병연맹(World Federation of Hemophilia, WFH) 지침서에 따라서 응고인자 수준을 유지하면서 다수의 발치를 포함한 관혈적 치과 치료를 받았다. 이와 같이 혈우병 환자에서 다수의 발치를 시행할 때 주기적인 혈액검사를 통한 응고인자 수준의 관리와 복잡한 의과적 처치가 요구된다. 따라서 다수의 발치가 요구되는 경우 전신마취 하에 가능한 모든 치과치료를 시행하는 것이 효과적이고 효율적인 방법이 될 수 있다.

양에서 막형 산화기를 사용하여 심폐바이패스할 경우 백혈구격리 및 자유라디칼로 중재되는 폐손상 (Leukocyte Sequestration and Free Radical-Mediated Lung Injury in Ovine Cardiopulmonary bypass Using Membrane Oxygenator)

  • 김원곤;신윤철;서정욱
    • Journal of Chest Surgery
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    • 제32권11호
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    • pp.978-983
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    • 1999
  • Background: Complement activation with transpulmonary leukocyte sequestration is considered a main mediator leading to ischemia-reperfusion lung(I-R) injury. We studied the role of leukocytes in the formation of I-R injury in ovine cardiopulmonary bypass(CPB) model with a membrane oxygenator. Material and Method: Five sheep were used. CPB circuitry consisted of a roller pump(American Optical Corp., Greenwich, CT, USA) and a membrane oxygenator(UNIVOX-IC, Bentley, Baxter Health Corp, Irvine, CA, USA). The CPB time was fixed at 120 min. Ten minutes after the start of CPB, total CPB was established. Thereafter a total CPB of 100 min was performed, followed by another 10 min of partial CPB. The CPB was discontinued and the animals were fully recovered. For measuring left and right atrial leukocyte counts, blood samples were taken before thoracotomy, 5 min and 109 in after the start of CPB, and 30 min and 120 min after weaning. C3a was measured before thoracotomy, 109 min after the start of CPB, and 30 min and 120 min after weaning. Plasma malondialdehyde(MDA) was checked before thoracotomy, 109 min after the start of CPB, and 30 min after weaning. One to two grams of lung tissue were taken for water content measurement before thoracotomy, 109 min after the start of CPB, and 30 min after weaning. Lung biopsy specimens were examined by light and electron microscopy. Result: Of 5 animals, 4 survived the experimental procedures. Of these, 3 animals survived on a long-term basis. No significant differences in transpulmonary gradients of leukocyte were found and no significant complement activation was expressed by C3a levels. MDA level did not show significant changes related to lung reperfusion despite an increase after the start of CPB. On both light and electron microscopic examinations, mild to moderate acute lung change was observed. Interstitial edema, leakage of erythrocytes into the alveolar space and endothelial cell swelling were the main findings. Water content of the lung showed a slight increase after the start of CPB, but there was no statistical significance. Conclusion: These findings indicate that ischemia-repersusion lung injury may not be from complement activation-leukocyte sequestration but from another source of oxygen free radicals related to CPB.

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두개골에 발생한 고립성 형질세포종 - 증례보고 - (Solitary Plasmacytoma of the Skull - A Case Report -)

  • 한정훈;박해관;민창기;조정기;박성찬;조경근;이경진;나형균;최창락;강준기
    • Journal of Korean Neurosurgical Society
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    • 제29권5호
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    • pp.701-705
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    • 2000
  • Solitary plasmacytomas are rare and account for 5-10% of all plasma cell disorders. These tumors are categorized as solitary plasmacytomas of bone(osseous) or extramedullary plasmacytomas(non-osseous). About a half of solitary plasmacytomas of bone occur in the spine but rarely in the skull. We report a case of solitary plasmacytoma of the skull presented with a painless palpable left parietal calvarial mass in an otherwise asymptomatic 38- year-old man. Skull radiographs showed a large radiolucent lesion with well defined non-sclerotic margins. Computed tomograph scan demonstrated a markedly enhancing mass extending from the epidural to the subcutaneous space. The patient underwent surgery and tumor was completely excised. Pathological examination showed tumor to be a plasmacytoma synthesizing IgG. Postoperatively, the patient received radiotherapy. There was no evidence of systemic involvement on postoperative laboratory wokups. Our recommended treatment is a complete surgical excision combined with postoperative radiation therapy. The patient should be follwed carefully for more than 10 years because of either local recurrence or possible progression to multiple myeloma.

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Effect of GnRH Immunization on Testicular Function in Colts

  • Tshewang, U.;Dowsett, K.F.;Knott, L.;Jackson, A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제12권3호
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    • pp.348-353
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    • 1999
  • Ten Australian Stock Horses colts (five yearling and five 3-year old colts) of which 2 yearlings and 2 three year old colts served as control animals while 3 yearlings and 3 three year old colts received two GnRH immunizations within 4 weeks interval were used in this study. By the 5th to 6th week after immunization, the GnRH antibody titres in the plasma rose above 1:1000 and attained peak levels of 1:6500 by the 8th week and gradually declined to about 1:3000 by the 10th week in both the age groups. The testosterone and androstenedione concentrations of the control colts in both age groups were significantly greater (p<0.05) than that of the vaccinated groups. During the immunosuppression period, the vaccinated colts behaved like geldings. Semen could not be collected from 2 of the 3 three-year old vaccinated colts. The testicular dimensions, testicular weight, parenchymal weight, seminiferous tubule volumes, interstitial space volumes, Leydig cell volume, seminiferous tubule % of the control colts were significantly greater than those of the vaccinated colts in both the age groups. The 3-year old control colts had a significantly (p<0.05) greater % of Leydig cells than the control and vaccinated 1-year old colts. There was arrest of spermatogenesis with complete absence of sperm in the testes of the vaccinated colts while there was various stages of spermatogenesis in those of the control colts. Morphometric analysis demonstrated that the 3-year old colts had significantly (p<0.05) greater DSP/gm of testis and DSP/testis than those of the 1-year old control colts. This study elucidated that the GnRH immunization could suppress the testicular function of the 3-year old and yearling colts.

Comparison analysis of superconducting solenoid magnet systems for ECR ion source based on the evolution strategy optimization

  • Wei, Shaoqing;Lee, Sangjin
    • 한국초전도ㆍ저온공학회논문지
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    • 제17권2호
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    • pp.36-40
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    • 2015
  • Electron cyclotron resonance (ECR) ion source is an essential component of heavy-ion accelerator. For a given design, the intensities of the highly charged ion beams extracted from the source can be increased by enlarging the physical volume of ECR zone [1]. Several models for ECR ion source were and will be constructed depending on their operating conditions [2-4]. In this paper three simulation models with 3, 4 and 6 solenoid system were built, but it's not considered anything else except the number of coils. Two groups of optimization analysis are presented, and the evolution strategy (ES) is adopted as an optimization tool which is a technique based on the ideas of mutation, adaptation and annealing [5]. In this research, the volume of ECR zone was calculated approximately, and optimized designs for ECR solenoid magnet system were presented. Firstly it is better to make the volume of ECR zone large to increase the intensity of ion beam under the specific confinement field conditions. At the same time the total volume of superconducting solenoids must be decreased to save material. By considering the volume of ECR zone and the total length of solenoids in each model with different number of coils, the 6 solenoid system represented the highest coil performance. By the way, a certain case, ECR zone volume itself can be essential than the cost. So the maximum ECR zone volume for each solenoid magnet system was calculated respectively with the same size of the plasma chamber and the total magnet space. By comparing the volume of ECR zone, the 6 solenoid system can be also made with the maximum ECR zone volume.

단일이미지에서의 초해상도 영상 생성을 위한 패치 정보 기반의 선형 보간 연구 (Patch Information based Linear Interpolation for Generating Super-Resolution Images in a Single Image)

  • 한현호;이종용;정계동;이상훈
    • 한국융합학회논문지
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    • 제9권6호
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    • pp.45-52
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    • 2018
  • 본 논문은 단일 이미지에서 초해상도 영상 생성을 위해 저해상도 이미지에서 생성한 패치정보를 기반으로 선형보간하는 방법을 제안하였다. 기존의 초해상도 생성 방법인 전역 공간의 회귀 모델을 사용하면 특정 영역에 대해 참조할 정보가 부족하여 일반적으로 품질이 떨어지는 결과가 나타난다. 이러한 결과를 보완하기 위해 제안하는 방법은 초해상도 이미지 생성 과정에서 영상을 패치 단위로 지역을 분할하여 의미있는 정보를 수집하고, 수집된 정보를 기반으로 초해상도 이미지 생성을 위해 확장시킨 이미지 매트릭스 영역의 구성정보를 분석하여 선형 보간 과정을 거치고 패치정보를 대응시켜 탐색한 최적의 패치 정보를 기준으로 선형 보간하는 방법을 제안하였다. 실험을 위해 원본 이미지를 복원된 영상과 PSNR, SSIM으로 비교 평가하였다.