• Title/Summary/Keyword: Contrast agent

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Ammoniacal Leaching for Recovery of Valuable Metals from Spent Lithium-ion Battery Materials (폐리튬이온전지로부터 유가금속을 회수하기 위한 암모니아 침출법)

  • Ku, Heesuk;Jung, Yeojin;Kang, Ga-hee;Kim, Songlee;Kim, Sookyung;Yang, Donghyo;Rhee, Kangin;Sohn, Jeongsoo;Kwon, Kyungjung
    • Resources Recycling
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    • v.24 no.3
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    • pp.44-50
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    • 2015
  • Recycling technologies would be required in consideration of increasing demand in lithium ion batteries (LIBs). In this study, the leaching behavior of Ni, Co and Mn is investigated with ammoniacal medium for spent cathode active materials, which are separated from a commercial LIB pack in hybrid electric vehicles. The leaching behavior of each metal is analyzed in the presence of reducing agent and pH buffering agent. The existence of reducing agent is necessary to increase the leaching efficiency of Ni and Co. The leaching of Mn is insignificant even with the existence of reducing agent in contrast to Ni and Co. The most conspicuous difference between acid and ammoniacal leaching would be the selective leaching behavior between Ni/Co and Mn. The ammoniacal leaching can reduce the cost of basic reagent that makes the pH of leachate higher for the precipitation of leached metals in the acid leaching.

Fermentation Process for Mass Production of Clitocybin A, a New Anti-Wrinkle Agent from Clitocybe aurantiaca and Evaluation of Inhibitory Activity on Matrix Metalloproteinase-1 Expression (Clitocybe aurantiaca 균주가 생산하는 주름개선소재 clitocybin A의 대량 발효생산 및 MMP-1 발현저해활성)

  • Kim, Kwan-Chul;Lee, Hyeok-Won;Lee, Hong-Won;Choo, Soo-Jin;Yoo, Ick-Dong;Ha, Byung-Jo
    • Microbiology and Biotechnology Letters
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    • v.42 no.2
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    • pp.194-201
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    • 2014
  • Clitocybin A is a novel anti-wrinkle cosmetic agent produced by the strain from a Korean native mushroom Clitocybe aurantiaca. In this study, fermentation, extraction, and purification conditions for a large scale production of clitocybin A were optimized, and its cytotoxicity and inhibition activity on the expression of matrix metalloproteinase-1 (MMP-1) were characterized. The mass production of anti-wrinkle agent was achieved according to the 300 L fermentation process with a fed-batch cultivation using the modified yeast-maltose (YM) broth, and a total of 12.5 kg of cell mass was obtained in a 120 L culture broth for 14 days. After extraction and purification, clitocybin A was identified by HPLC. The cytotoxicity of clitocybin A was examined by the MTT assay. When assayed at 100 and 200 ${\mu}g/ml$ concentrations, clitocybin A showed no cytotoxicity, demonstrating safety. The inhibition activity of clitocybin A on the expression of MMP-1 was examined against UV irradiation. Oleanolic acid (control group) showed a relatively low MMP-1 inhibiting activity (ca. 16.7%) at 10 ${\mu}g/ml$ and showed increased cytotoxicity at higher concentrations. In contrast, clitocybin A showed no cytotoxicity at 100 ${\mu}g/ml$, and exhibited a relatively high MMP-1-inhibiting activity (33.1%). These findings indicate that clitocybin A may be a safe and effective anti-wrinkle agent for use in functional cosmetics.

The Efficiency of Vascular Embolization Using Alginate Gel : An Experimental Study in Rabbit (알지네이트 젤을 이용한 혈관 색전술의 유용성 : 토끼에서의 실험적 연구)

  • Lee, Woo-Baek;Kang, Yeong-Han;Kim, Jong-Ki
    • Journal of radiological science and technology
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    • v.32 no.1
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    • pp.61-67
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    • 2009
  • Purpose : The purpose of this study was to investigate the applicability of poly-L-guluronic alginate (PGA) gel in vascular embolization with angiography simulation. Materials and Methods : To prepare a gel-forming PGA from no guluronate-rich Laminaria japonica, a new acid hydrolysis method was employed with a lower HCL concentration (0.03 M) and a shorter treatment time (5 min). The obtained PGAs were selected based on gel stability and viscosity. Glass aneurysm model was used to simulate gel embolization in vitro. Then, finally, the PGA was used to embolize the renal vascular system by using a rabbit model and angiography. Results : Glass aneurysm model was made to simulate gel embolization procedure. PGA solution was injected from pump through 2-way catheter. Subsequent injection of $CaCl_2$ successfully formed gels inside aneurysm model that conforming to its inner contour. In rabbit model, first, renal artery and aorta leading to the right kidney were ligated to block blood flow, then conventional contrast agent was injected through aorta to check the arterial patency to the left kidney. In sequential artery injection method, PGA and $CaCl_2$ were injected through renal artery sequentially via a single catheter. Re-injection of contrast agent after removing ligated aorta showed blood flow to the right kidney but no flow in the left kidney. This result demonstrated a complete blocking of blood flow due to gel formation in vascular bed of the left kidney. Conclusion : Instillation of calcium alginate into aneurysm model and arterial system in vivo produced an embolization that better fills and conforms to the contour of aneurysms or blocking vascular bed completely. Therefore, PGA was effective endovascular occlusion materials and provide an efficiency of vascular angiography.

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Synthesis of Homing Peptide-Immobilized Magnetite Nanoparticles through PEG Spacer and Their Biomedical Applications (PEG 스페이서를 통해 Homing 펩타이드를 고정화한 산화철 나노입자의 제조 및 생의학적 응용)

  • Lee, Sang-Min;Xing, Zhi-Cai;Shin, Yong-Suk;Gu, Tae-Hyung;Lee, Byung-Heon;Huh, Man-Woo;Kang, Inn-Kyu
    • Polymer(Korea)
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    • v.36 no.5
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    • pp.586-592
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    • 2012
  • Iron oxides ($Fe_3O_4$) are metabolically secreted after endocytosed by cells, indicating no cytotoxicity. Therefore, they are widely used as a contrast agent before photographing of magnetic resonance imaging. In this study, iron oxide nanoparticles are synthesized by the co-precipitation method and subsequently immobilized with a homing peptide (AP), which specifically interacts with interleukin-4 receptor located on the membrane of endothelial and bladder cancer cells. The size of AP-immobilized iron oxide particle is about 39 nm. Intracellular uptake of the AP-immobilized iron oxide nanoparticles was investigated using bladder cancer cells and fibroblasts as the control. As the result, the nanoparticles are specificially uptaken by bladder cancer cells. However, the nanoparticles are not specificially uptaken by fibroblast. It could be said that the AP-immobilized iron oxide nanoparticles have a potential to be used as a contrast agent for early diagnosis of cancer.

THE STUDY OF CORRELATION WITH CYCLOSPORIN A INDUCED GINGIVAL OVERGROWTH AND LOCAL FACTORS (Cyclosporin A 유도 치은증식과 국소적 요인과의 상관관계에 대한 연구)

  • Ko, Eun-Ah;Yoo, Hyung-Keun;Shin, Hyung-Shik
    • Journal of Periodontal and Implant Science
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    • v.25 no.1
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    • pp.14-23
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    • 1995
  • Cyclosporin A is a powerful immunosuppressive agent commonly used for patients receiving organ transplants. Like phenytoin and the calcium channel blockers, the drug is associated with gingival overgrowth. The purpose of this study was to compare the correlation with gingival overgrowth score and clinical indices(i.e, : plaque index, papillary bleeding index, probing depth) and correlation with gingival overgrowth score and microorganism distribution in use of phase contrast microscope. After renal tranplant, taking cyclosporin A 40 patients participating in this investigation. Post - transplatation cyclosporin medication period was average $17.53{\pm}15.75$ months. In previous study reported that gingival overgrowth is an adverse side - effects seen in about 25-81% of patient taking cyclosporin A. The results were as follows : 1. Gingival overgrowth prevalence in taking cyclosporin A patients was 77.5%. Prevalence rate of region was anterior region(26 teeth, 55.3%), molar region(14 teeth, 29.8%), premolar region(7 teeth, 14.8%) in turns. Gingival overgrowth score by Angelopoulos & Goaz method was molar region($1.56{\pm}0.81$), anterior region($1.52{\pm}0.75$), premolar region($1.14{\pm}0.90$) in turns. 2. Medication period was not correlation with gingival overgrowth score. 3. Clinical indices and gingival overgrowth score were as follows. 1) Plaque index and gingival overgrowth score was significantly correlated(p

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First-Pass Observation using Tailored-RF Gradient Echo (TRFGE) MR Imaging in Cat Brain (자기공명 Tailored-RF 경사자계반향영상법을 이용한 고양이 뇌에서의 First-Pass관찰)

  • 문치웅;노용만
    • Journal of Biomedical Engineering Research
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    • v.16 no.2
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    • pp.209-216
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    • 1995
  • Recently, a new tailored RF gradient echo (TRFGE) sequence was reported. This technique not only enhances the magnetic susceptibility effect but also allows us to measure local changes in brain oxygenation. In this study, a phantom and cat brain experiments were performed on a 4.7 Tesla BIQSPEC (BRUKER) instrument with a 26 cm gradient system. We have demonstrated that the signal intensity (SI) of the TRFGE sequence varies according to the concentration of susceptibility contrast agent. Three capillary tubes with different concentrations of Gd-DTPA (0.01, 0.05, 0.1 mMOI/l) were placed at the middle of a cylindrical water phantom. Using both TRFGE and conventional gradient echo (CGE) sequences, phantom images of the slices which contain all three tubes were obtained. For the animal experiment, cats were anesthetized and ventilated using halotane (0.5%) and a $N_2O/ O_2$ mixture (2:1), and blood pressure and heart rate were monitored and kept normal. For the observation of tue first pass of Gd- DTPA, imaging was started at t = 0. At t = 8 ~ 12s, 0.2 mMol/Kg Gd-DTPA was manually injected in the femoral vein. The imaging parameters were TRITE = 25/10 msec, flip angle = $30^{\circ}$, FOV = 10cm, image matrix size = $128{\times}128$ with 64 phase encodings and the image data acquisition window was 10 msec. SI-time curves were then obtained from a series of 30 images which were collected at 2 sec intervals using both CGE and TRFGE pulse sequences before, during, and following the contrast injection.

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Comparison between Computer Tomography and Magnetic Resonance Imaging in the Diagnosis of Small Hepatocellular Carcinoma

  • Lertpipopmetha, Korn;Tubtawee, Teeravut;Piratvisuth, Teerha;Chamroonkul, Naichaya
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.11
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    • pp.4805-4811
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    • 2016
  • Background: Hepatocellular carcinomas (HCCs) less than 2 cm in diameter generally demonstrate a good outcome after curative therapy. However, the diagnosis of small HCC can be problematic and requires one or more dynamic imaging modalities. This study aimed to compare the sensitivity and agreement between CT and MRI for the diagnosis of small HCCs. Methods: CT and/or MRI scans of HCCs (1-2 cm) diagnosed by histopathology or typical vascular pattern according to the 2005 AASLD criteria were blindly reviewed by an abdominal radiologist. The reports were defined as conclusive/typical when arterial enhancement and washout during the portal/delayed phases were observed and as inconclusive when typical vascular patterns were not observed. The sensitivity and Cohen's kappa (k) for agreement were calculated. Results: In 27 patients, 27 HCC nodules (1-2 cm) were included. Diagnosis with a single-imaging modality (CT or MRI) was 81 % versus 48 % (p = 0.01). The CT sensitivity was significantly higher than MRI (78 % versus 52 %, p = 0.04). Among 27 nodules that underwent both CT and MRI, a discordance in typical enhancement patterns was found (k = 0.319, p = 0.05). In cases with inconclusive CT results, MRI gave only an additional 3.7 % sensitivity to reach a diagnosis. In contrast, further CT imaging following inconclusive MRI results gave an additional 29.6 % sensitivity.Conclusions: A single typical imaging modality is sufficient to diagnose small HCCs. Compared with MRI, multiphasic CT has a higher sensitivity. The limitations of MRI could be explained by the greater need for patient cooperation and the types of MRI contrast agent.

Gastrotomy Approach Retrieval of Esophageal Foreign Body using Long Forceps Technique in Five Dogs (위 절개술 접근과 긴 겸자를 이용한 식도 내 이물 제거 5례)

  • Yoon, Hun-Young;Kang, Myung-Gon;Jeong, Soon-Wuk
    • Journal of Veterinary Clinics
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    • v.26 no.6
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    • pp.628-631
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    • 2009
  • Five dogs presented to the Veterinary Medical Teaching Hospital of the Konkuk University and Hangang Animal Hospital with a history of foreign body ingestion. On physical examination, five dogs showed lethargy, anorexia, or vomiting. Plain radiographs revealed that radiopaque foreign bodies lodged in the heart base or caudal thoracic esophagus. Positive contrast esophagogram revealed that large foreign bodies severely expanded the esophagus and there was no evidence of leakage of the contrast agent from the esophagus into the thoracic cavity. Gastrotomy for retrieval of esophageal foreign bodies using long forceps technique was performed. Esophageal foreign bodies were successfully retrieved in all dogs. The follow-ups were completed 10 days to 2 years after surgery. The follow-up information was based on physical examination by veterinarians and telephone interview with owners. The owners reported that there was no evidence of complications related to surgery such as vomiting, regurgitation, dysphagia, gagging, hyper-salivation, or anorexia in all dogs.

Modified Upper Gastrointestinal Study Using Methylcellulose After Administration of Barium Suspension : Comparison with Conventional Series (바륨 현탁액과 메틸셀룰로스(Methylcellulose)를 사용한 변형 상부위장관조영술 :전통적 바륨조영술과의 비교)

  • 이기창;최민철;서민호;정주현;윤정희
    • Journal of Veterinary Clinics
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    • v.17 no.2
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    • pp.411-415
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    • 2000
  • For comparison with conventional barium-gastrointestinal study, modified method using barium and methylcellulose was performed in 16 normal dogs (4-8 kg) divided into two groups. The group 1 received 8ml/kg of 40% w/v barium suspension only, and group 2 had taken 15 ml/kg of 0.6% w/v methylcellulose after administration 4 ml/kg of 40% w/v barium suspension by feeding tube. The barium suspension was prepared mixing full strength-barium suspension with water and methylcellulose solution was produced by blending methylcellulose sterilized water Sequential radiographs, lateral and ventrodorsal projections were obtained at 5 minute, 20 minute,40 minute. 60 minute and every 30 minutes thereafter, until the contrast is seen in the large intestine Inage qual- ity was rated by three veterinary radiologists as " poor" " fair ". "good", or "excellent" We analyzed the relationship between image quality,, transit time. Between two techniques, the modified method with 4ml of 40% w/v barium suspension and 15 ml of 0.6% w/v methylcellulose showed much better image quality ["excellent" result in 7 of the 8 subjects (88%)] and shorter transit time (107 minutes) toe the cecum. In addition, the best image quality was obtained at 20 and 40 minutes after admin-istration of contrast agent. It call be concluded the modified gastrointestinal study using methylcel-lulose after administration of barium suspension was a simple technique and easily improved the image quality and diagnostic accuracy of gstrointestinal disorders in small animal.racy of gstrointestinal disorders in small animal.

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Primary Hepatic Lymphoma: MR Imaging and Pathologic Correlation (일차성 간림프종: 자기공명영상과 병리소견의 연관)

  • Kim, Han-Na;Shin, Yu-Ri;Rha, Sung-Eun;Jung, Eun-Sun;Oh, Soon-Nam;Choi, Joon-Il;Jung, Seung-Eun;Lee, Young-Joon
    • Investigative Magnetic Resonance Imaging
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    • v.14 no.2
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    • pp.151-155
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    • 2010
  • Primary hepatic lymphoma is extremely rare, representing less than 1% of all extranodal lymphomas. We report MR imaging features and pathologic correlation of a case of primary hepatic lymphoma. MR images showed a large lobulated mass with gradual contrast enhancement, resembling intrahepatic cholangiocarcinoma. However, both hepatobiliary phase image obtained 20 minutes after injection of hepatocyte specific contrast agent and diffusion-weighted image demonstrated characteristic three layered pattern representing viable lymphoma in the outer layer, tumor necrosis in the middle layer and necrotic hepatic parenchyma in the center.