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Hong SY, Ko SW, Choi HJ, Lee JH. Multi-Walled Carbon Nanotube/Biodegradable Poly(butyleneadipate-co-butyleneterephthalate) Nanocomposites and Their Physical Characteristics. J MACROMOL SCI B 2011. [DOI: 10.1080/00222348.2011.583199] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- S. Y. Hong
- a Department of Polymer Science and Engineering , Inha University , Incheon, Korea
| | - S. W. Ko
- a Department of Polymer Science and Engineering , Inha University , Incheon, Korea
| | - H. J. Choi
- a Department of Polymer Science and Engineering , Inha University , Incheon, Korea
| | - J. H. Lee
- b Advanced Materials Division , Korea Research Institute of Chemical Technology , Daejeon, Korea
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Hong MK, Ko SW, Park JH, Choi HJ, Kim JH. Multi walled carbon nanotube nanocomposites with biodegradable poly(butylene succinate) and their physical characteristics. J Nanosci Nanotechnol 2011; 11:5352-5357. [PMID: 21770188 DOI: 10.1166/jnn.2011.3795] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
In order to examine the influence of multi walled carbon nanotube (MWNT) on physical properties of its biodegradable polymer nanocomposite, biodegradable poly(buthylene succinate) (PBS), which was synthesized from diols and dicarboxylic acids, and MWNT nanocomposites were prepared via a melt-mixing method using a co-rotating intermeshing twin screw extruder. Microstructure of the PBS/MWNT nanocomposites and MWNT were investigated via both scanning electron microscopy and transmission electron microscopy. Their rheological properties were also characterized via rotation and oscillation tests using a rotational rheometer with parallel-plate geometry. It was found that shear viscosity, storage modulus and loss modulus of the nanocomposites examined by a rotational rheometer increased with the MWNT content. Especially their sharp increase for MWNT content of ca. 2.0 wt% was observed, indicating its percolation threshold from the rheological viewpoint which was higher than its electrical percolation threshold (1.0 wt%).
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Affiliation(s)
- M K Hong
- Department of Polymer Science and Engineering, Inha University, Incheon 402-751, Korea
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Ko SW, Kim YK, Jin GY, Lee SY, Kim CS. Granulocytic sarcoma manifested as a parametrial mass mimicking a haemorrhagic abscess: a case report with CT and MR findings. Br J Radiol 2007; 80:e128-30. [PMID: 17704306 DOI: 10.1259/bjr/60325018] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Granulocytic sarcoma is a neoplasm arising from myeloid precursor cells and frequently accompanies leukaemia and myeloproliferative disorders. Granulocytic sarcoma can arise anywhere, and it frequently involves bones, perineural tissues and lymph nodes. However, granulocytic sarcoma in the female genital organs is uncommon, and it is extremely rare that it presents as an adnexal or parametrial mass. We report here the CT and MR findings in a case of granulocytic sarcoma that manifested as a uterine cervical and parametrial mass mimicking a haemorrhagic abscess in a 50-year-old woman with chronic myelogenous leukaemia.
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MESH Headings
- Abscess/diagnosis
- Cervix Uteri/diagnostic imaging
- Cervix Uteri/pathology
- Diagnosis, Differential
- Female
- Hemorrhage/diagnosis
- Humans
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/complications
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnostic imaging
- Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology
- Magnetic Resonance Imaging, Interventional
- Middle Aged
- Parametritis/diagnostic imaging
- Parametritis/pathology
- Sarcoma, Myeloid/diagnosis
- Sarcoma, Myeloid/diagnostic imaging
- Sarcoma, Myeloid/pathology
- Tomography, X-Ray Computed
- Uterus/pathology
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Affiliation(s)
- S W Ko
- Department of Diagnostic Radiology, Chonbuk University Medical School, 634-18 Geumam 2 dong, Dukjin gu, Jeonju City, Chonbuk, South Korea, 561-712
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Ko SW, Shin SS, Jeong YY. Mesenteric inflammatory myofibroblastic tumor mimicking a necrotized malignant mass in an adult: case report with MR findings. ACTA ACUST UNITED AC 2005; 30:616-9. [PMID: 15791485 DOI: 10.1007/s00261-004-0296-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2004] [Accepted: 03/10/2004] [Indexed: 11/29/2022]
Abstract
Inflammatory myofibroblastic tumors are lesions that usually affect young adults and children. Numerous extrapulmonary sites of these tumors have been found, but the mesentery is a very unusual location for an inflammatory myofibroblastic tumor and it is extremely rare in an older patient. Inflammatory myofibroblastic tumor of the mesentery is often demonstrated as a large and infiltrative lesion with heterogeneous enhancement. Its diagnosis is recognized as difficult and it often mimics malignant tumor. We report a case of mesenteric inflammatory myofibroblastic tumor mimicking a necrotized malignant mass in a 55-year-old man who was examined with magnetic resonance imaging. To our knowledge, this is the first report of magnetic resonance imaging of mesenteric inflammatory myofibroblastic tumor with extensive central necrosis in an older patient.
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Affiliation(s)
- S W Ko
- Department of Diagnostic Radiology, Chonbuk University Medical School, 634-18 Geumam 2 dong, Dukjin-gu, Jeonju City, Chonbuk 561-712, South Korea.
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Abstract
Partially deacetylated chitins with different degrees of deacetylation (DD) were prepared by alkaline treatment under homogeneous conditions, and the effect of DD on their solubility was discussed in terms of crystal structure and mode of hydrogen bonding. With an increase in the treatment time, the DD of chitin increased proportionally. The chitin became soluble in dilute acetic acid at the DD of ca. 28% or over and soluble in water at the DD of ca. 49%. The solubility of the partially deacetylated chitins had a close relationship with their crystal structure, crystallinity, and crystal imperfection as well as the glucosamine content. The wide-angle X-ray diffractometry (WAXD) revealed that the chitin with ca. 28% DD retained the crystal structure of alpha-chitin with significantly reduced crystallinity and perfection of the crystallites. The water-soluble chitin of ca. 49% DD had a new crystal structure similar to that of beta-chitin rather than either alpha-chitin or chitosan, suggesting that the homogeneous deacetylation transformed the crystal structure of chitin from the alpha to the beta form. Some hydrogen bonds existing in raw alpha-chitin were found to be missing at a DD of ca. 49%.
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Affiliation(s)
- Y W Cho
- Department of Fiber and Polymer Science, Seoul National University, Seoul 151-742, Korea
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Kim JS, Hwang HZ, Yeo SH, Ko SW, Song SM, Kim YK, Kim DJ, Oh HY, Choi HY, Kim MK, Toru S, Kohsaka T, Kim Y, Jin DK. Morphologic evaluation and integrin expression profile of renal tubular cells cultured from percutaneous renal biopsy specimen. Ren Fail 2001; 23:21-9. [PMID: 11256526 DOI: 10.1081/jdi-100001280] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Kidney biopsy is an indispensible procedure for making a pathologic diagnosis of renal diseases by fixing and staining the biopsy specimen. However, it is not a routine procedure to culture the cells from a renal biopsy specimen directly, or to utilize the cultured cells for any kind of diagnostic or functional evaluation. In this study, primary culture of the renal tubular epithelial cells was tried from a piece of percutaneous kidney biopsy specimen. Successive passages of the cells were possible until fourth passage. With these cells, morphologic characteristics of the cultured cells and integrin expression profiles were investigated. On light and electron microscopy, these cells were characterized by the cobblestone-like growth, presence of microvilli and tight junction, and the preservation of polarity. Immunohistochemical studies demonstrated the epithelial nature of these cells and particularly their differentiation from renal tubular epithelial cells, of either proximal or distal nephronic segment. The integrin profile confirms the epithelial nature of the cell. We hope that our results facilitate the understanding of pathophysiology of renal tubular cells from the patient directly.
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Affiliation(s)
- J S Kim
- Department of Pediatrics, School of Medicine, Samsung Medical Center, Samsung Biomedical Research Center, Seoul, Korea
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Abstract
A 72-year-old man who had suffered several episodes of syncope was diagnosed as having hyperinsulinemic hypoglycemia. Although imaging studies and percutaneous transhepatic portal venous sampling did not reveal the existence of any tumors in the pancreas, distal pancreatectomy was performed because the possibility of a small pancreatic endocrine tumor could not be completely rejected. External examination of the surgically removed pancreas did not reveal any tumors. Microscopically, the pancreas exhibited diffuse islet cell hyperplasia without nesidioblastosis. The patient remains euglycemic and has tolerated 24-hour fasting without any medication for a period of 10 months after the operation.
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Affiliation(s)
- Y W Kim
- Department of Pathology, College of Medicine, Kyung Hee University, Seoul, Korea.
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Abstract
Water-soluble chitin (WSC) was prepared by controlling degree of deacetylation (DD) and molecular weight of chitin through alkaline and ultrasonic treatment. Its accelerating effect on wound healing in rats was compared with those of chitin and chitosan. Full-thickness skin incision was made on the backs of the rats and then three kinds of powders (chitin, chitosan, WSC) and an aqueous solution of WSC were embedded in the wounds. The tensile strength and the hydroxyproline content of the wounded skins were measured and histological examination was performed. The WSC was found to be more efficient than chitin or chitosan as a wound-healing accelerator. The wound treated with WSC solution was completely reepithelialized, granulation tissues in the wound were nearly replaced by fibrosis and hair follicles were almost healed at 7 days after initial wounding. Also, the WSC-solution-treated skin had the highest tensile strength and the arrangement of collagen fibers in the skin was similar to normal skins. The WSC solution is considered to be a suitable wound-healing agent due to its easy application and high effectiveness.
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Affiliation(s)
- Y W Cho
- Department of Fiber and Polymer Science, Seoul National University, South Korea
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Abstract
Osteopontin (OP) and osteonectin (ON) are bone matrix proteins produced by mammary and other cancers. These proteins may play a role in tumor invasion and metastasis through integrin-mediated signal transduction. We evaluated expressions of OP and ON in 253 resected infiltrating ductal carcinoma of the breast, using immunohistochemical staining and follow-up data. OP and ON were detected 87.4% and 54.2% of 253 cases, respectively. The OP and ON positive staining were localized in the cytoplasm of carcinoma cells. OP and ON did not correlate with various clinicopathological parameters, such as age, lymph node involvement, tumor size, histologic grade, expression of p53 and estrogen receptor (ER). In the multivariate model, lymph node involvement and histologic grade were statistically significant prognostic factors. Assessed by a log rank test, the 5-year-survival rates of OP and ON positive groups and their negative groups were not statistically different. In conclusion, OP and ON immunopositivity of infiltrating ductal carcinomas of the breast provide no additional prognostic information in this study.
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Affiliation(s)
- Y W Kim
- Department of Pathology, College of Medicine, Kyung Hee University, Seoul, Korea.
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Khoo MC, Anholm JD, Ko SW, Downey R, Powles AC, Sutton JR, Houston CS. Dynamics of periodic breathing and arousal during sleep at extreme altitude. Respir Physiol 1996; 103:33-43. [PMID: 8822221 DOI: 10.1016/0034-5687(95)00057-7] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
To determine whether nocturnal periodic breathing (PB) at altitude is due primarily to unstable control of ventilation or the inability to maintain stable sleep states, we performed visual and computer analyses of the electroencephalographic and respiratory records of healthy volunteers at simulated altitudes of 4572, 6100 and 7620 m. Transient arousals were associated with < 52% of the apneas identified; thus, the PB cycle was not always associated with transient arousal. Following the termination of oxygen breathing, the reinitiation of PB was not dependent on the occurrence of arousal as the primary event. The transition from apnea to breathing preceded the appearance of arousal by approximately 1 to 4 sec. Ventilatory drive in the breaths immediately following arousal was significantly larger than corresponding control breaths, matched for SaO2. Our findings suggest that altitude-induced PB is unlikely to result from primary fluctuations in state. Arousals promote the development of PB with apnea and help to sustain these episodes, but are not necessary for their initiation.
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Affiliation(s)
- M C Khoo
- Biomedical Engineering Dept., University of Southern California, Los Angeles, USA
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Park YK, Kim YW, Kim JW, Choi YK, Ko YT, Ko SW, Yang MH. Bilateral primary pigmented nodular adrenocortical disease--a case of report describing a rare cause of Cushing's syndrome. J Korean Med Sci 1994; 9:450-7. [PMID: 7786440 PMCID: PMC3054224 DOI: 10.3346/jkms.1994.9.6.450] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
A case of Cushing's syndrome due to bilateral pigmented nodular adrenal disease in a 35-year-old male is presented. The adrenals showed multiple, black, variable sized nodules. Histologically the cells contained lipofuscin and either had a clear cytoplasm or an eosinophilic cytoplasm with a prominent nucleus. Lymphocytic infiltration and fatty metaplasia within the nodules are two of the prominent histological features. There is extreme internodular atrophy which suggests that primary pigmented nodular adrenocortical disease is a non-adrenocorticotropic hormone dependent condition. Since the disorder appears to involve primarily the cortex of both adrenals, the treatment of choice is bilateral adrenalectomy followed by steroid replacement. The characteristic clinicopathological manifestations that separate this diagnosis from other types of adrenal disease are also discussed. This is the first reported case in Korea to be documented with the pertinent clinicopathological findings.
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Affiliation(s)
- Y K Park
- Department of Pathology, School of Medicine, Kyunghee University, Seoul, Korea
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