Polyurethane (PU) ionomers were prepared using various types of polyol (PTAd, PCL, PTMG, and PPG)... more Polyurethane (PU) ionomers were prepared using various types of polyol (PTAd, PCL, PTMG, and PPG) and isocyanate (MDI, HDI, and IPDI), together with different extender (DMPA) contents, degree of neutralization, and number average molecular weight (M n) of polyol. Modulus (E′), strength (σb), and glass transition temperature (T g) significantly increased with the increased amount of extender and extender neutralization. Among three of the iocyanate used, PU from MDI gave the highest modulus, strength, andT g. With regard to theM n of PTAd (600, 1000, 2000), PU from PTAd 600M n gave the highest modulus, strength, andT g, due probably to the highest hard segment content and phase mixing. On the other hand, PU from PTAd 2000M n gave significantly improved strength over PTAd 1000M n, and the highest elongation. The results were interpreted in terms of soft-segment crystallization, and soft-hard phase separation, which was concluded from the lowered softT g.
Purpose The gonadotropin-releasing hormone (GnRH) test results of girls with precocious puberty w... more Purpose The gonadotropin-releasing hormone (GnRH) test results of girls with precocious puberty were analyzed to determine whether this test can efficiently and clearly differentiate between central precocious puberty (CPP) and other disorders. Methods Clinical and ...
Aqueous dispersions of polyurethane (PU) ionomers were prepared from hydrogenated diphenylmethane... more Aqueous dispersions of polyurethane (PU) ionomers were prepared from hydrogenated diphenylmethane diisocyanate (H12MDI), poly(tetramethylene adipate) glycol (PTAd), bisphenol A propylene oxide ether glycol (LER), and dimethylol propionic acid (DMPA) as potential ionic centres. The urethaneforming reaction was carried out in N-methyl-2-pyrrolidone (NMP) with dibutyltin dilaurate (DBT) as catalyst. The effects of DMPA and bisphenol A polyol on the particle size of the dispersions, and the physical properties of the emulsion cast films were determined. It was found that the particle size decreased with DMPA, and increased with bisphenol A polyol contents. Initial modulus and tensile strength of the emulsion cast films increased, and the elongation at break decreased with DMPA and bisphenol A polyol contents. The results were interpreted in terms of increased interchain Coulombic forces and urethane linkages with DMPA, and increased chain rigidity of PU with bisphenol A polyol incorporation.
Objectives A paucity of data exists on actual pathology of the contemporary patients strictly cat... more Objectives A paucity of data exists on actual pathology of the contemporary patients strictly categorized as having low-risk prostate cancer. We tried to identify useful preoperative predictors of Gleason score upgrading in patients who underwent radical retropubic prostatectomy (RRP) for low-risk prostate cancer diagnosed via multi-core prostate biopsy. Methods A total of 203 patients who underwent radical RRP for low-risk prostate cancer, as defined by D’Amico et al.'s classification (clinical stage ≤T2a, biopsy Gleason sum ≤6, and PSA ≤10 ng/ml), detected via multi (≥12)-core prostate biopsy were enrolled. We reviewed patients preoperative and pathological data. Results Among all subjects, 81 (39.9%) were upgraded to Gleason score ≥7 after RRP, whereas no downgrading was observed. In multivariate analysis, only preoperative PSA level (P = 0.024) and number of positive cores (P = 0.027) were observed to be independent predictors of Gleason score upgrading following RRP. Also, Gleason core upgrading was observed to be significantly associated with extraprostatic extension of tumor (P < 0.001) and positive surgical margin (P = 0.002). Conclusions A significant proportion of patients with low-risk prostate cancer as defined by D’Amico et al.’s classification diagnosed via multi-core prostate biopsy in contemporary period may have Gleason score upgrading following RRP. For patients with low-risk prostate cancer, preoperative PSA level and number of positive cores may be useful predictors of Gleason score upgrading, which was observed to significantly associated with other adverse pathologic features.
ABSTRACT: Fiber forming polyacrylonitriles (PAN) were modified by copolymerizing acrylonitrile mo... more ABSTRACT: Fiber forming polyacrylonitriles (PAN) were modified by copolymerizing acrylonitrile monomer with methyl acrylate (MA) and 2-acrylamido-2-methyl propane sulfonic acid (AP), respectively, and blended with collulose acetate (CA). Fibers of MA-PAN, AP-...
Pleomorphic xanthoastrocytoma (PXA) is a rare primary brain tumor, which usually involves the sup... more Pleomorphic xanthoastrocytoma (PXA) is a rare primary brain tumor, which usually involves the superficial cortex in children and young adults. Although PXA is considered an astrocytic tumor, recent studies suggest the presence of neuronal differentiation and an origin from multipotential precursor cells. To clarify the clinicopathological characteristics, which have not been well established due to the rarity of this tumor, eight cases of histologically proven PXA were retrospectively analyzed, paying special attention to immunohistochemical findings and associated cortical dysplasia. Three males and five females of median age 17 years (range, 11–24 years) were enrolled in the study. All patients presented with epilepsy. Tumor sites included the temporal (n = 5), frontal (n = 2), and temporoparietal (n = 1) lobes. 18F-FDG PET (positron emission tomography) showed hypometabolism of PXA. Immunohistochemical study was performed in six cases using various antibodies for glial and neuronal markers. Gross total resection of the PXA was achieved in all cases. The follow-up period ranged from 7 to 14 years except for two recent cases. All patients are doing well with neither radiological nor clinical evidence of recurrence. The surgical treatment rendered all patients seizure free. The three temporal lobe PXAs were associated with cortical dysplasia. In one tumor, clusters of dysmorphic ganglion cells were found. All examined PXAs demonstrated immunoreactivity for both neuronal and glial markers in the various tumor cells. The immunohistochemical studies undertaken as a part of this study support the proposed astrocytic and neuronal differentiation of PXA, and indicate that PXA is probably a developmental neuroglial tumor with prominent glioproliferative changes associated with focal cortical dysplasia. Cortical dysplasia may be a cause of persistent epilepsy even after complete surgical excision of PXA.
Polyurethane (PU) ionomers were prepared using various types of polyol (PTAd, PCL, PTMG, and PPG)... more Polyurethane (PU) ionomers were prepared using various types of polyol (PTAd, PCL, PTMG, and PPG) and isocyanate (MDI, HDI, and IPDI), together with different extender (DMPA) contents, degree of neutralization, and number average molecular weight (M n) of polyol. Modulus (E′), strength (σb), and glass transition temperature (T g) significantly increased with the increased amount of extender and extender neutralization. Among three of the iocyanate used, PU from MDI gave the highest modulus, strength, andT g. With regard to theM n of PTAd (600, 1000, 2000), PU from PTAd 600M n gave the highest modulus, strength, andT g, due probably to the highest hard segment content and phase mixing. On the other hand, PU from PTAd 2000M n gave significantly improved strength over PTAd 1000M n, and the highest elongation. The results were interpreted in terms of soft-segment crystallization, and soft-hard phase separation, which was concluded from the lowered softT g.
Purpose The gonadotropin-releasing hormone (GnRH) test results of girls with precocious puberty w... more Purpose The gonadotropin-releasing hormone (GnRH) test results of girls with precocious puberty were analyzed to determine whether this test can efficiently and clearly differentiate between central precocious puberty (CPP) and other disorders. Methods Clinical and ...
Aqueous dispersions of polyurethane (PU) ionomers were prepared from hydrogenated diphenylmethane... more Aqueous dispersions of polyurethane (PU) ionomers were prepared from hydrogenated diphenylmethane diisocyanate (H12MDI), poly(tetramethylene adipate) glycol (PTAd), bisphenol A propylene oxide ether glycol (LER), and dimethylol propionic acid (DMPA) as potential ionic centres. The urethaneforming reaction was carried out in N-methyl-2-pyrrolidone (NMP) with dibutyltin dilaurate (DBT) as catalyst. The effects of DMPA and bisphenol A polyol on the particle size of the dispersions, and the physical properties of the emulsion cast films were determined. It was found that the particle size decreased with DMPA, and increased with bisphenol A polyol contents. Initial modulus and tensile strength of the emulsion cast films increased, and the elongation at break decreased with DMPA and bisphenol A polyol contents. The results were interpreted in terms of increased interchain Coulombic forces and urethane linkages with DMPA, and increased chain rigidity of PU with bisphenol A polyol incorporation.
Objectives A paucity of data exists on actual pathology of the contemporary patients strictly cat... more Objectives A paucity of data exists on actual pathology of the contemporary patients strictly categorized as having low-risk prostate cancer. We tried to identify useful preoperative predictors of Gleason score upgrading in patients who underwent radical retropubic prostatectomy (RRP) for low-risk prostate cancer diagnosed via multi-core prostate biopsy. Methods A total of 203 patients who underwent radical RRP for low-risk prostate cancer, as defined by D’Amico et al.'s classification (clinical stage ≤T2a, biopsy Gleason sum ≤6, and PSA ≤10 ng/ml), detected via multi (≥12)-core prostate biopsy were enrolled. We reviewed patients preoperative and pathological data. Results Among all subjects, 81 (39.9%) were upgraded to Gleason score ≥7 after RRP, whereas no downgrading was observed. In multivariate analysis, only preoperative PSA level (P = 0.024) and number of positive cores (P = 0.027) were observed to be independent predictors of Gleason score upgrading following RRP. Also, Gleason core upgrading was observed to be significantly associated with extraprostatic extension of tumor (P < 0.001) and positive surgical margin (P = 0.002). Conclusions A significant proportion of patients with low-risk prostate cancer as defined by D’Amico et al.’s classification diagnosed via multi-core prostate biopsy in contemporary period may have Gleason score upgrading following RRP. For patients with low-risk prostate cancer, preoperative PSA level and number of positive cores may be useful predictors of Gleason score upgrading, which was observed to significantly associated with other adverse pathologic features.
ABSTRACT: Fiber forming polyacrylonitriles (PAN) were modified by copolymerizing acrylonitrile mo... more ABSTRACT: Fiber forming polyacrylonitriles (PAN) were modified by copolymerizing acrylonitrile monomer with methyl acrylate (MA) and 2-acrylamido-2-methyl propane sulfonic acid (AP), respectively, and blended with collulose acetate (CA). Fibers of MA-PAN, AP-...
Pleomorphic xanthoastrocytoma (PXA) is a rare primary brain tumor, which usually involves the sup... more Pleomorphic xanthoastrocytoma (PXA) is a rare primary brain tumor, which usually involves the superficial cortex in children and young adults. Although PXA is considered an astrocytic tumor, recent studies suggest the presence of neuronal differentiation and an origin from multipotential precursor cells. To clarify the clinicopathological characteristics, which have not been well established due to the rarity of this tumor, eight cases of histologically proven PXA were retrospectively analyzed, paying special attention to immunohistochemical findings and associated cortical dysplasia. Three males and five females of median age 17 years (range, 11–24 years) were enrolled in the study. All patients presented with epilepsy. Tumor sites included the temporal (n = 5), frontal (n = 2), and temporoparietal (n = 1) lobes. 18F-FDG PET (positron emission tomography) showed hypometabolism of PXA. Immunohistochemical study was performed in six cases using various antibodies for glial and neuronal markers. Gross total resection of the PXA was achieved in all cases. The follow-up period ranged from 7 to 14 years except for two recent cases. All patients are doing well with neither radiological nor clinical evidence of recurrence. The surgical treatment rendered all patients seizure free. The three temporal lobe PXAs were associated with cortical dysplasia. In one tumor, clusters of dysmorphic ganglion cells were found. All examined PXAs demonstrated immunoreactivity for both neuronal and glial markers in the various tumor cells. The immunohistochemical studies undertaken as a part of this study support the proposed astrocytic and neuronal differentiation of PXA, and indicate that PXA is probably a developmental neuroglial tumor with prominent glioproliferative changes associated with focal cortical dysplasia. Cortical dysplasia may be a cause of persistent epilepsy even after complete surgical excision of PXA.
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