17 results on '"Choe YS"'
Search Results
2. Strictly Lobar Microbleeds Reflect Amyloid Angiopathy Regardless of Cerebral and Cerebellar Compartments.
- Author
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Jung YH, Jang H, Park SB, Choe YS, Park Y, Kang SH, Lee JM, Kim JS, Kim J, Kim JP, Kim HJ, Na DL, and Seo SW
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- Aged, Aged, 80 and over, Aniline Compounds, Basal Ganglia Hemorrhage diagnostic imaging, Benzothiazoles, Cerebellar Nuclei diagnostic imaging, Cerebellum diagnostic imaging, Female, Humans, Magnetic Resonance Imaging, Male, Positron-Emission Tomography, Radiopharmaceuticals, Stilbenes, Thiazoles, Cerebellar Diseases diagnostic imaging, Cerebral Amyloid Angiopathy diagnostic imaging, Cerebral Hemorrhage diagnostic imaging, Cerebral Small Vessel Diseases diagnostic imaging, Cognitive Dysfunction diagnostic imaging, Dementia diagnostic imaging, Intracranial Hemorrhages diagnostic imaging, Thalamic Diseases diagnostic imaging
- Abstract
Background and Purpose: We aimed to determine whether lobar cerebellar microbleeds or concomitant lobar cerebellar and deep microbleeds, in the presence of lobar cerebral microbleeds, attribute to underlying advanced cerebral amyloid angiopathy pathology or hypertensive arteriopathy., Methods: We categorized 71 patients with suspected cerebral amyloid angiopathy markers (regardless of the presence of deep and cerebellar microbleeds) into 4 groups according to microbleed distribution: L (strictly lobar cerebral, n=33), L/LCbll (strictly lobar cerebral and strictly lobar cerebellar microbleeds, n=13), L/Cbll/D (lobar, cerebellar, and deep microbleeds, n=17), and L/D (lobar and deep, n=8). We additionally categorized patients with cerebellar microbleeds into 2 groups according to dentate nucleus involvement: strictly lobar cerebellar (n=16) and dentate (n=14). We then compared clinical characteristics, Aβ (amyloid-β) positivity on PET (positron emission tomography), magnetic resonance imaging cerebral amyloid angiopathy markers, and cerebral small vessel disease burden among groups., Results: The frequency of Aβ positivity was higher in the L and L/LCbll groups (81.8% and 84.6%) than in the L/Cbll/D and L/D groups (37.5% and 29.4%; P <0.001), while lacune numbers were lower in the L and L/LCbll groups (1.7±3.3 and 1.7±2.6) than in the L/Cbll/D and L/D groups (8.0±10.3 and 13.4±17.7, P =0.001). The L/LCbll group had more lobar cerebral microbleeds than the L group (93.2±121.8 versus 38.0±40.8, P =0.047). The lobar cerebellar group had a higher Aβ positivity (75% versus 28.6%, P =0.011) and lower lacune number (2.3±3.7 versus 8.6±1.2, P =0.041) than the dentate group., Conclusions: Strictly lobar cerebral and cerebellar microbleeds are related to cerebral amyloid angiopathy, whereas any combination of concurrent lobar and deep microbleeds suggest hypertensive angiopathy regardless of cerebral or cerebellar compartments.
- Published
- 2020
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3. Synergistic effects of longitudinal amyloid and vascular changes on lobar microbleeds.
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Kim YJ, Kim HJ, Park JH, Kim S, Woo SY, Kwak KC, Lee JM, Jung NY, Kim JS, Choe YS, Lee KH, Moon SH, Lee JH, Kim YJ, Werring DJ, Na DL, and Seo SW
- Subjects
- Aged, Amyloidosis genetics, Amyloidosis physiopathology, Aniline Compounds, Apolipoproteins E genetics, Brain physiopathology, Cerebral Hemorrhage genetics, Cerebral Hemorrhage physiopathology, Cerebral Small Vessel Diseases genetics, Cerebral Small Vessel Diseases physiopathology, Disease Progression, Female, Follow-Up Studies, Humans, Incidence, Longitudinal Studies, Magnetic Resonance Imaging, Male, Neuropsychological Tests, Positron-Emission Tomography, Prospective Studies, Radiopharmaceuticals, Thiazoles, White Matter diagnostic imaging, White Matter physiopathology, Amyloidosis diagnostic imaging, Brain diagnostic imaging, Cerebral Hemorrhage diagnostic imaging, Cerebral Small Vessel Diseases diagnostic imaging
- Abstract
Objective: To determine whether amyloid and hypertensive cerebral small vessel disease (hCSVD) changes synergistically affect the progression of lobar microbleeds in patients with subcortical vascular mild cognitive impairment (svMCI)., Methods: Among 72 patients with svMCI who underwent brain MRI and [
11 C] Pittsburgh compound B (PiB)-PET, 52 (72.2%) completed the third year of follow-up. These patients were evaluated by annual neuropsychological testing, brain MRI, and follow-up PiB-PET., Results: Over 3 years, 31 of 52 patients (59.6%) had incident cerebral microbleeds (CMBs) in the lobar and deep regions. Both baseline and longitudinal changes in lacune numbers were associated with increased numbers of lobar and deep microbleeds, while baseline and longitudinal changes in PiB uptake ratio were associated only with the progression of lobar microbleeds, especially in the temporal, parietal, and occipital areas. Regional white matter hyperintensity severity was also associated with regional lobar CMBs in the parietal and occipital regions. There were interactive effects between baseline and longitudinal lacune number and PiB retention on lobar microbleed progression. Increased lobar, but not deep, CMBs were associated with decreased scores in the digit span backward task and Rey-Osterrieth Complex Figure Test., Conclusions: Our findings suggest that amyloid-related pathology and hCSVD have synergistic effects on the progression of lobar microbleeds, providing new clinical insight into the interaction between amyloid burden and hCSVD on CMB progression and cognitive decline with implications for developing effective prevention strategies., (© 2016 American Academy of Neurology.)- Published
- 2016
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4. Relation between primary tumor FDG avidity and site of first distant metastasis in patients with breast cancer.
- Author
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Lim CH, Moon SH, Cho YS, Im YH, Choe YS, Kim BT, and Lee KH
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- Adult, Breast Neoplasms diagnosis, Breast Neoplasms mortality, Breast Neoplasms therapy, Chi-Square Distribution, Female, Humans, Liver Neoplasms diagnosis, Liver Neoplasms secondary, Lung Neoplasms diagnosis, Lung Neoplasms epidemiology, Lung Neoplasms secondary, Lymphatic Metastasis, Middle Aged, Neoplasm Invasiveness pathology, Neoplasm Recurrence, Local mortality, Neoplasm Recurrence, Local therapy, Neoplasm Staging, Palliative Care methods, Prognosis, Sensitivity and Specificity, Survival Rate, Breast Neoplasms pathology, Fluorodeoxyglucose F18 pharmacokinetics, Neoplasm Recurrence, Local pathology, Positron Emission Tomography Computed Tomography methods
- Abstract
Identification of tumor imaging features associated with metastatic pattern may allow better understanding of cancer dissemination. Here, we investigated how primary tumor F-fluorodeoxyglucose (FDG) avidity influences the first site of breast cancer metastasis.Subjects were 264 patients with advanced breast cancer who underwent positron emission tomography/computed tomography at diagnosis and had metastasis at presentation (n = 193) or metastatic relapse after surgery (n = 71). Primary tumor FDG avidity (maximum SUV [SUVmax] ≥10.1) was compared with histology and first metastatic sites.The most common site of first metastasis was the bone, occurring in 62.7% of patients with metastasis at presentation and 38.0% of those with metastatic relapse. First metastasis to lung occurred in 30.1% and 35.2%, and to liver in 25.4% and 15.2% of respective groups. In patients with metastasis at presentation, primary tumors were FDG avid in 98/193 cases, and this was associated with more frequent first metastasis to lung (37.8% vs 22.1%; P = 0.018). In patients with metastasis relapse, primary tumors were FDG avid in 31/71 cases, and this was associated with more frequent first metastasis to lung (48.4% vs 25.0%; P = 0.041) and liver (29.0% vs 5.0%; P = 0.008). In patients with metastasis relapse, primary tumors that were FDG avid but hormone receptor negative had more first metastasis to lung (57.9% vs 26.9%; P = 0.016).FDG-avid primary breast tumors have favored first spread to the lung and liver, which suggests that tumor cells with heightened glycolytic activity better colonize these organs.
- Published
- 2016
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5. Gray and white matter changes linking cerebral small vessel disease to gait disturbances.
- Author
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Kim YJ, Kwon HK, Lee JM, Cho H, Kim HJ, Park HK, Jung NY, San Lee J, Lee J, Jang YK, Kim ST, Lee KH, Choe YS, Kim YJ, Na DL, and Seo SW
- Subjects
- Aged, Aged, 80 and over, Cerebral Cortex pathology, Female, Humans, Male, Prospective Studies, Cerebral Small Vessel Diseases complications, Cerebral Small Vessel Diseases diagnosis, Gait Disorders, Neurologic diagnosis, Gait Disorders, Neurologic etiology, Gray Matter pathology, White Matter pathology
- Abstract
Objective: To investigate the topographic changes of white matter (WM) integrity and cortical thickness related to gait disturbances and determine whether these neural correlates mediate the association between cerebral small vessel disease (CSVD) and gait disturbances., Methods: A total of 129 patients with subcortical vascular cognitive impairment were included. CSVD severity was quantified as global and regional WM hyperintensities (WMH) volume and lacune and microbleed numbers. Amyloid burdens were assessed using Pittsburgh compound B (PiB)-PET scanning. Gait score was measured using a standardized scale. WM integrity was assessed by applying tract-based spatial statistics. Cortical thickness was measured using surface-based methods. Path analysis for gait score was performed using regional CSVD markers as predictors and fractional anisotropy (FA) and cortical thickness as mediators., Results: Periventricular WMH (PWMH) volume was associated with gait score, regardless of other CSVD. PiB retention ratio was not associated with gait score. Gait score was correlated with FA in the frontal and parietal WM and bilateral corpus callosum and with cortical thinning in the bilateral frontal and lateral temporo-parieto-occipital regions. Path analysis for gait score showed that PWMH contributed to gait disturbances with the mediation of mean FA or cortical thickness., Conclusions: Our findings suggest that WMH-related cortical thinning as well as disrupted integrity of periventricular WM is linked to gait disturbances., (© 2016 American Academy of Neurology.)
- Published
- 2016
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6. Early- vs late-onset subcortical vascular cognitive impairment.
- Author
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Jang YK, Kwon H, Kim YJ, Jung NY, Lee JS, Lee J, Chin J, Im K, Jeon S, Lee JM, Seong JK, Kim JH, Kim S, Choe YS, Lee KH, Kim ST, Kim JS, Lee JH, Na DL, Seo SW, and Kim HJ
- Subjects
- Adult, Age of Onset, Aged, Aged, 80 and over, Amyloid metabolism, Brain Mapping, Female, Humans, Magnetic Resonance Imaging methods, Male, Middle Aged, Neuropsychological Tests, Cerebral Cortex pathology, Cognition Disorders pathology
- Abstract
Objective: To evaluate the differences between early-onset subcortical vascular cognitive impairment (EO-SVCI) and late-onset subcortical vascular cognitive impairment (LO-SVCI) with regard to pathologic burden, structural changes, and cognitive function., Methods: We prospectively recruited 142 patients from a single referral center. Patients were divided into EO-SVCI (n = 30, age at onset <65 years) and LO-SVCI (n = 112, age at onset ≥ 65 years) groups. All patients underwent neuropsychological tests, 3T brain MRI, and [(11)C] Pittsburgh compound B (PiB)-PET. We compared pathologic burden such as small vessel disease and amyloid burden; structural changes such as structural network, cortical thickness, and hippocampal volume; and cognitive function between EO-SVCI and LO-SVCI., Results: EO-SVCI patients had more lacunes, while LO-SVCI patients had higher PiB standardized uptake value ratios. EO-SVCI patients exhibited more severe structural network disruptions in the frontal area, while LO-SVCI patients exhibited more severe cortical and hippocampal atrophy. Although disease severity did not differ between the 2 groups, frontal-executive dysfunction was more severe in EO-SVCI patients., Conclusions: EO-SVCI patients showed more vascular related factors, while LO-SVCI patients exhibited more Alzheimer disease-related characteristics. The greater number of lacunes in EO-SVCI might account for the more severe frontal network disruption and frontal-executive dysfunction, while the greater amyloid burden in LO-SVCI might account for the more severe cortical and hippocampal atrophy. Our findings suggest that the age at onset is a crucial factor that determines distinct features in SVCI patients, such as pathologic burden, structural changes, and cognitive function., (© 2016 American Academy of Neurology.)
- Published
- 2016
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7. Effects of amyloid and vascular markers on cognitive decline in subcortical vascular dementia.
- Author
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Ye BS, Seo SW, Kim JH, Kim GH, Cho H, Noh Y, Kim HJ, Yoon CW, Woo SY, Kim SH, Park HK, Kim ST, Choe YS, Lee KH, Kim JS, Oh SJ, Kim C, Weiner M, Lee JH, and Na DL
- Subjects
- Aged, Aged, 80 and over, Cohort Studies, Female, Follow-Up Studies, Humans, Longitudinal Studies, Magnetic Resonance Imaging trends, Male, Middle Aged, Prospective Studies, Amyloid metabolism, Amyloid beta-Peptides metabolism, Cognition Disorders diagnosis, Cognition Disorders metabolism, Dementia, Vascular diagnosis, Dementia, Vascular metabolism
- Abstract
Objective: To determine the independent and synergistic effects of amyloid and small vessel disease (SVD) burden on longitudinal cognitive decline in patients with subcortical vascular dementia (SVaD)., Methods: A longitudinal cohort study was conducted involving patients from outpatient clinics of 2 tertiary referral centers. Sixty-one patients with SVaD were prospectively recruited and underwent MRI, 11C-Pittsburgh compound B (PiB) PET at baseline, and a 3-year annual neuropsychological follow-up. Effects of PiB positivity and SVD markers (white matter hyperintensities [WMH], lacunes, and microbleeds) on longitudinal cognitive decline were evaluated using generalized estimation equation after controlling for age, sex, education, APOE4 allele, and follow-up interval., Results: When individual neuropsychological tests were used as outcome measures, PiB positivity was associated with faster cognitive decline in attention, visuospatial, visual memory, and global cognition function. Higher WMH burden was associated with faster cognitive decline in attention, visuospatial, visual recognition memory, and semantic/phonemic fluency function, whereas lacunes and microbleeds had no significant effects. When global dementia rating (Clinical Dementia Rating sum of boxes) was considered as an outcome measure, however, only PiB positivity was associated with faster cognitive decline. Significant interactions between PiB positivity and higher SVD burden were found to affect cognitive decline in semantic word fluency (from WMH burden) and global dementia rating (from microbleed burden)., Conclusions: In SVaD patients, amyloid burden, independently or interactively with SVD, contributed to longitudinal cognitive decline. Amyloid deposition was the strongest poor prognostic factor., (© 2015 American Academy of Neurology.)
- Published
- 2015
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8. Hybrid lymph node imaging using 64Cu-labeled mannose-conjugated human serum albumin with and without indocyanine green.
- Author
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Kang CM, An GI, and Choe YS
- Subjects
- Animals, Heterocyclic Compounds, 1-Ring chemistry, Humans, Isotope Labeling, Mice, Mice, Inbred ICR, Models, Molecular, Optical Imaging, Positron-Emission Tomography, Protein Conformation, Tissue Distribution, Copper Radioisotopes, Indocyanine Green chemistry, Lymph Nodes diagnostic imaging, Mannose chemistry, Multimodal Imaging methods, Serum Albumin chemistry
- Abstract
Objective: Human serum albumin (HSA), which has 58 Lys residues, one Cys residue, and indocyanine green (ICG) adsorption sites, can be used as a multifunctional platform for the development of hybrid imaging probes. In this study, we prepared 64Cu-labeled mannose-conjugated HSA with and without ICG ([64Cu]1-ICG and [64Cu]1, respectively) and compared hybrid PET/near-infrared fluorescence (NIRF) imaging with positron emission tomography (PET)/Cerenkov luminescence (CL) imaging of lymph nodes (LNs)., Materials and Methods: 1,4,7,10-Tetraazacyclododecane-N,N',N'',N'''-tetraacetic acid (DOTA)/mannose-conjugated HSA (1) was synthesized by conjugating mannose molecules to Lys residues and a DOTA molecule to a Cys residue of HSA. Compound 1 was then labeled with Cu ([64Cu]1), and the resulting [64Cu]1 was adsorbed with ICG ([64Cu]1-ICG). PET/NIRF or PET/CL imaging and subsequent biodistribution studies were performed in ICR mice after injection of the probes into the foot pads., Results: The numbers of mannose and DOTA molecules conjugated to HSA were 7.17 ± 0.49 and 0.95 ± 0.18, respectively. The site-specific conjugation of one DOTA molecule to HSA was sufficient for 64Cu-labeling with high efficiency (96.0 ± 1.1%). PET/NIRF and PET/CL imaging and subsequent biodistribution studies demonstrated that the probes were avidly taken up by the popliteal LNs (PO), with a slightly higher uptake ratio of the PO to the lumbar LNs by [64Cu]1., Conclusion: In-vivo studies suggest that [64Cu]1 has more specific and selective binding to mannose receptors in the PO than [64Cu]1-ICG.
- Published
- 2015
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9. Clinical effect of white matter network disruption related to amyloid and small vessel disease.
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Kim HJ, Im K, Kwon H, Lee JM, Kim C, Kim YJ, Jung NY, Cho H, Ye BS, Noh Y, Kim GH, Ko ED, Kim JS, Choe YS, Lee KH, Kim ST, Lee JH, Ewers M, Weiner MW, Na DL, and Seo SW
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- Aged, Aged, 80 and over, Cognition Disorders diagnosis, Cognition Disorders epidemiology, Cognition Disorders metabolism, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Positron-Emission Tomography, Prospective Studies, Systemic Vasculitis diagnosis, Systemic Vasculitis epidemiology, Systemic Vasculitis metabolism, Amyloid beta-Peptides metabolism, Microcirculation physiology, Nerve Net metabolism, Nerve Net pathology, White Matter metabolism, White Matter pathology
- Abstract
Background: We tested our hypothesis that the white matter network might mediate the effect of amyloid and small vessel disease (SVD) on cortical thickness and/or cognition., Methods: We prospectively recruited 232 patients with cognitive impairment. Amyloid was assessed using Pittsburgh compound B-PET. SVD was quantified as white matter hyperintensity volume and lacune number. The regional white matter network connectivity was measured as regional nodal efficiency by applying graph theoretical analysis to diffusion tensor imaging data. We measured cortical thickness and performed neuropsychological tests., Results: SVD burden was associated with decreased nodal efficiency in the bilateral frontal, lateral temporal, lateral parietal, and occipital regions. Path analyses showed that the frontal nodal efficiency mediated the effect of SVD on the frontal atrophy and frontal-executive dysfunction. The temporoparietal nodal efficiency mediated the effect of SVD on the temporoparietal atrophy and memory dysfunction. However, Pittsburgh compound B retention ratio affected cortical atrophy and cognitive impairment without being mediated by nodal efficiency., Conclusions: We suggest that a disrupted white matter network mediates the effect of SVD, but not amyloid, on specific patterns of cortical atrophy and/or cognitive impairment. Therefore, our findings provide insight to better understand how amyloid and SVD burden can give rise to brain atrophy or cognitive impairment in specific patterns., (© 2015 American Academy of Neurology.)
- Published
- 2015
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10. Seoul criteria for PiB(-) subcortical vascular dementia based on clinical and MRI variables.
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Kim GH, Lee JH, Seo SW, Ye BS, Cho H, Kim HJ, Noh Y, Yoon CW, Chin JH, Oh SJ, Kim JS, Choe YS, Lee KH, Kim ST, Jeong JH, and Na DL
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- Aged, Aged, 80 and over, Area Under Curve, Atrophy diagnosis, Atrophy etiology, Dementia, Vascular complications, Female, Humans, Intracranial Hemorrhages diagnosis, Intracranial Hemorrhages etiology, Leukoencephalopathies diagnosis, Leukoencephalopathies etiology, Male, Outcome Assessment, Health Care methods, Outcome Assessment, Health Care standards, Positron-Emission Tomography, Prospective Studies, Psychiatric Status Rating Scales, Republic of Korea, Stroke, Lacunar diagnosis, Stroke, Lacunar etiology, Vision Disorders diagnosis, Vision Disorders etiology, Brain diagnostic imaging, Brain pathology, Dementia, Vascular diagnosis, Magnetic Resonance Imaging methods, Magnetic Resonance Imaging standards
- Abstract
Objective: The purpose of this study was to propose new criteria for differentiating Pittsburgh compound B (PiB)-negative from PiB-positive subcortical vascular dementia (SVaD) using clinical and MRI variables., Methods: We measured brain amyloid deposition using PiB-PET in 77 patients with SVaD. All patients met DSM-IV criteria for vascular dementia and had severe white matter hyperintensities on MRI, defined as a cap or band ≥ 10 mm as well as a deep white matter lesion ≥ 25 mm. Eleven models were considered to differentiate PiB(-) from PiB(+) SVaD using 4 variables, including age, number of lacunes, medial temporal atrophy (MTA), and APOE ε4. The ideal cutoff values in each of the 11 models were selected using the highest Youden index., Results: A total of 49 of 77 patients (63.6%) tested negative for PiB retention, while 28 (36.4%) tested positive for PiB retention. The ideal model for differentiating PiB(-) from PiB(+) SVaD was as follows: age ≤ 75 years, ≥ 5 lacunes, and MTA ≤ 3, which together yielded an accuracy of 67.5%., Conclusion: When patients meet the DSM-IV criteria for vascular dementia and also have severe white matter hyperintensities, younger age, greater number of lacunes, and lesser MTA, these are predictive of a PiB(-) scan in patients with SVaD., Classification of Evidence: This study provides Class II evidence that the combination of younger age, greater number of lacunes, and lesser MTA identifies patients with SVaD at lower risk of Alzheimer disease pathology.
- Published
- 2014
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11. Synthesis and evaluation of radioiodine-labelled CP-118,954 for the in-vivo imaging of acetylcholinesterase.
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Lee I, Choe YS, Ryu EK, Choi BW, Choi JY, Choi Y, Lee KH, and Kim BT
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- Animals, Cholinesterase Inhibitors chemical synthesis, Cholinesterase Inhibitors pharmacokinetics, Drug Evaluation, Preclinical, Iodine Radioisotopes chemistry, Isotope Labeling, Isoxazoles chemistry, Male, Metabolic Clearance Rate, Mice, Mice, Inbred ICR, Piperidines chemistry, Radionuclide Imaging, Radiopharmaceuticals chemical synthesis, Radiopharmaceuticals pharmacokinetics, Tissue Distribution, Acetylcholinesterase metabolism, Brain diagnostic imaging, Brain enzymology, Iodine Radioisotopes pharmacokinetics, Isoxazoles pharmacokinetics, Piperidines pharmacokinetics
- Abstract
Objectives: Alzheimer's disease (AD) is characterized by reduced acetylcholinesterase (AChE) activity in the post-mortem tissues of AD patients. Therefore, AChE has been an attractive target for the diagnosis of AD. In the present study, 5,7-dihydro-3-[2-(1-(phenylmethyl)-4-piperidinyl)ethyl]-6H-pyrrolo[3,2-f]-1,2-benzisoxazol-6-one (CP-118,954), a potent AChE inhibitor, was labelled with radioiodine and evaluated as an AChE imaging agent for SPECT., Methods: Radioiodine-labelled CP-118,954 was prepared from CP-144,885 and [(125)I]iodobenzyl bromide, and anti-AChE activities of iodine-substituted CP-118,954 were measured. Metabolism studies were carried out in samples of blood and whole brain of mice injected with 2-[(123)I]iodo-CP-118,954 ((123)I-1). Tissue distribution studies were also performed in mice injected with I-1, and samples of blood, thyroid, stomach, and brain tissue (cerebellum, striatum and cortex) were removed, weighed and counted., Results: Of the ligands, 2-iodo-CP-118,954 exhibited higher binding affinity for AChE (IC50=24 nM) than the other positional isomers. 2-[(125)I]Iodo-CP-118,954 was found to have a lipophilicity (log P=2.1) favouring brain permeability and metabolic stability in mouse brain, but a marginal target (striatum) to non-target (cerebellum) uptake ratio (1.1) in mouse brain., Conclusion: This result demonstrates that 2-[(125)I]iodo-CP-118,954 may be unsuitable for AChE imaging. These findings suggest that radioligands suitable for AChE imaging should have not only a specific structure but also a sub-nanomolar to low nanomolar IC50.
- Published
- 2007
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12. Incidence and radio-uptake patterns of femoral head avascular osteonecrosis at 1 year after renal transplantation: a prospective study with planar bone scintigraphy.
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Lee EJ, Lee KH, Huh WS, Yoon JK, Chung HW, Choi JY, Choe YS, Choi Y, Oh HY, and Kim BT
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- Adult, Female, Femur Head Necrosis metabolism, Follow-Up Studies, Humans, Incidence, Kidney Failure, Chronic metabolism, Korea epidemiology, Male, Radionuclide Imaging, Radiopharmaceuticals pharmacokinetics, Reproducibility of Results, Risk Factors, Sensitivity and Specificity, Femur Head Necrosis diagnostic imaging, Femur Head Necrosis epidemiology, Kidney Failure, Chronic epidemiology, Kidney Failure, Chronic rehabilitation, Kidney Transplantation statistics & numerical data, Risk Assessment methods, Technetium Tc 99m Medronate pharmacokinetics
- Abstract
Objectives: We prospectively investigated the incidence of femoral head avascular osteonecrosis (AVN) and radio-uptake patterns of femoral heads on bone scintigraphy at 1 year after renal transplantation., Methods: A total of 237 subjects (473 femoral heads) were included. A bone scintigraphy was performed at 12 +/- 1.1 months after renal transplantation, and 17 hips were painful at the time of bone scintigraphy. We graded the radioactivity in each femoral head as normal (grade 0), mildly increased (grade I), and definitely increased (grade II). Typical photon defects in the upper lateral femoral heads were evaluated separately. AVN was confirmed with clinical follow-up of more than 1 year and MRI and/or plain radiography findings., Results: Femoral head AVN was detected in 15 of the 237 patients and 23 of the 473 femoral heads. When grade I and II activities were used as positive criteria, bone scintigraphy had a sensitivity of 91.3% (100% with pain) and specificity of 74.0% (100% with pain) for AVN diagnosis. When only grade II activity was considered positive, the rates were 56.5% (80.0% with pain) and 99.5% (100% with pain), respectively. The presence of a typical photon defect had a low sensitivity of 47.8%, although the specificity was high (99.1%)., Conclusions: The incidence of femoral head AVN was low among a prospective cohort of renal transplantation recipients at the time of 1 year after engraftment. Planar bone scintigraphy is sufficient to diagnose AVN in symptomatic patients at risk for femoral head AVN using grade I and II activities as positive criteria.
- Published
- 2006
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13. Clinical significance of thyroid visualization on technegas ventilation scintigraphy.
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Choi JY, Jang HJ, Park JM, Lee KH, Choi Y, Choe YS, and Kim BT
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- Administration, Inhalation, Adult, Female, Humans, Male, Middle Aged, Pulmonary Embolism complications, Pulmonary Embolism diagnostic imaging, Radionuclide Imaging, Radiopharmaceuticals, Reproducibility of Results, Sensitivity and Specificity, Sodium Pertechnetate Tc 99m administration & dosage, Thyroid Diseases complications, Ventilation-Perfusion Ratio, Sodium Pertechnetate Tc 99m pharmacokinetics, Thyroid Diseases diagnostic imaging, Thyroid Diseases metabolism, Thyroid Gland diagnostic imaging, Thyroid Gland metabolism
- Abstract
Background: We investigated the clinical significance of thyroid visualization on technegas (TcG) ventilation scintigraphy (TcGS) based on the hypothesis that this visualization may be correlated with thyroid disease with high radioactive thyroid uptake (RATU)., Methods: From a total of 1022 consecutive patients undergoing TcG/99mTc macroaggregated albumin ventilation/perfusion (V/Q) scintigraphy to exclude pulmonary embolism, 114 who underwent in vitro thyroid function tests (TFTs) within 2 weeks of the lung scintigraphy were included in the retrospective study. In addition, in 10 patients in whom high RATU was noted on [99mTc]pertechnetate thyroid scintigraphy, TcGS was performed prospectively. The degree of thyroid activity in each patient was graded on a scale of 0 to 2 (grade 0 = no or faint uptake; grade 1 = mild uptake, but less than the lung; and grade 2 = strong uptake, similar to, or more than, the lung)., Results: Thyroid uptake was observed on TcGS in 17.5% of the patient group (20/114; 10 with grade 1, 10 with grade 2). Serum T3, T4 and TSH values differed significantly, depending on the grade of thyroid activity. All patients showing grade 2 thyroid uptake were clinically diagnosed as having Graves' disease. None of the 94 patients with grade 0 on TcGS had evidence of hyperthyroidism, although four patients had hypothyroidism. In the prospective group, all patients showed any visualization of the thyroid on TcGS (3 with grade 1, 7 with grade 2). The final diagnoses for these patients were Graves' disease in six, Hashimoto's thyroiditis in three and post-partum thyroiditis in one., Conclusion: Thyroid visualization during TcGS appears to be correlated with thyroid disease with high RATU. Such a finding may also deserve further evaluation for additional irregularities in thyroid function.
- Published
- 2004
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14. Synthesis and evaluation of 5,7-dihydro-3-[2-[1-(4-[18F]-fluorobenzyl)-4-piperidinyl]ethyl]-6H-pyrrolo[3,2-f]-1,2-benzisoxazol-6-one for in vivo mapping of acetylcholinesterase.
- Author
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Lee SY, Choe YS, Kim YR, Paik JY, Choi BW, Kim SE, Lee KH, Choi Y, and Kim BT
- Subjects
- Animals, Biomarkers metabolism, Fluorine Radioisotopes pharmacokinetics, Isotope Labeling methods, Isoxazoles chemistry, Male, Metabolic Clearance Rate, Mice, Mice, Inbred ICR, Organ Specificity, Piperidines chemistry, Radionuclide Imaging, Radiopharmaceuticals chemical synthesis, Rats, Tissue Distribution, Acetylcholinesterase metabolism, Brain diagnostic imaging, Brain metabolism, Isoxazoles pharmacokinetics, Piperidines pharmacokinetics, Radiopharmaceuticals pharmacokinetics
- Abstract
Objectives: Acetylcholinesterase (AChE) is an important cholinergic marker for the diagnosis of Alzheimer's disease (AD). A recent study has demonstrated that C-labelled 5,7-dihydro-7-methyl-3-[2-[1-(phenylmethyl)-4-piperidinyl]ethyl]-6H-pyrrolo[3,2-f]-1,2-benzisoxazol-6-one (CP-126,998) shows promising results. The demethylated form of this ligand (CP-118,954) is a more potent and selective inhibitor than CP-126,998. In this study, therefore, CP-118,954 was labelled with F and evaluated for the in vivo mapping of AChE., Methods: The 4-fluoro (1). and 2-fluoro (2). derivatives of CP-118,954 were synthesized from 4-methyl-3-nitroanisole in 11 steps. Their in vitro binding affinities to AChE were measured using Ellman's method. The preparation of [F]-1 was carried out by reductive alkylation of the piperidine precursor with 4-[F]-fluorobenzaldehyde, followed by high-performance liquid chromatography (HPLC) purification. In vitro autoradiography was performed by incubating rat brain coronal slices with [F]-1. Tissue distribution studies were performed in mouse brain and the data were expressed as the percentage of the injected dose per gram of tissue (%ID x g)., Results: Two fluorine-substituted AChE inhibitors were synthesized and their in vitro binding data showed that the 4-fluoro and 2-fluoro derivatives (1 and 2) had similar or superior binding affinity to that of the unsubstituted ligand, CP-118,954. The F-labelled ligand was synthesized in 20-35% radiochemical yield (EOS) and with high effective specific activity (36-42 GBq x micromol). Autoradiography showed high uptake of [F]-1 in the striatum and this striatal uptake was completely inhibited by the unlabelled ligand 1. Tissue distribution studies demonstrated that high radioactivity was accumulated in the striatum, an AChE-rich region., Conclusions: This study demonstrates that [F]-1 may hold promise as a radioligand for the in vivo mapping of AChE.
- Published
- 2004
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15. Cell uptake and tissue distribution of radioiodine labelled D-luciferin: implications for luciferase based gene imaging.
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Lee KH, Byun SS, Paik JY, Lee SY, Song SH, Choe YS, and Kim BT
- Subjects
- Animals, COS Cells, Chlorocebus aethiops, Gene Expression Regulation, Enzymologic physiology, Iodine Radioisotopes pharmacokinetics, Luciferases genetics, Male, Metabolic Clearance Rate, Mice, Mice, Inbred ICR, Organ Specificity, Radiopharmaceuticals pharmacokinetics, Rats, Rats, Sprague-Dawley, Recombinant Proteins metabolism, Spectrometry, Fluorescence methods, Tissue Distribution, Firefly Luciferin pharmacokinetics, Gene Expression Profiling methods, Luciferases metabolism
- Abstract
Optical luciferase gene imaging is emerging as a method to monitor gene expression in small animals. However, there is concern over how regional availability of exogenously administered substrate may affect photon emission. We thus synthesized [125I]iodo-D-luciferin, which demonstrated substrate characteristics for firefly luciferase, and investigated its cell uptake kinetics and in vivo biodistribution. Luminescence assays of luc gene transduced cells confirmed a linear decline in emitted light units with decreasing luciferin concentration. Both luc gene transduced and control cells demonstrated a low level of cellular uptake and rapid washout of [125I]iodo-D-luciferin, although early uptake was slightly higher for transduced cells (P < 0.005). Biodistribution in ICR mice demonstrated that early uptakes in liver, lung, myocardium and muscle were lower with intraperitoneal compared to intravenous administration. In view of the poor cell uptake, uptake levels (< 3%ID/g) suggest that substrate concentration may limit light emission rates in organs such as bone, muscle, myocardium, and particularly the brain. Thus, substrate availability should be considered as a potential limiting factor for photon emission efficiency in certain organs when attempting quantitative interpretation of optical luc gene imaging., (2003 Lippincott Williams & Wilkins)
- Published
- 2003
- Full Text
- View/download PDF
16. Use of insulin to improve [18 F]fluorodeoxyglucose labelling and retention for in vivo positron emission tomography imaging of monocyte trafficking.
- Author
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Paik JY, Lee KH, Byun SS, Choe YS, and Kim BT
- Subjects
- Animals, Humans, Hypoglycemic Agents, In Vitro Techniques, Liver blood supply, Liver diagnostic imaging, Liver metabolism, Lymphocytes diagnostic imaging, Lymphocytes metabolism, Male, Models, Animal, Radiopharmaceuticals pharmacokinetics, Rats, Rats, Sprague-Dawley, Reperfusion Injury diagnostic imaging, Reperfusion Injury metabolism, Sensitivity and Specificity, Time Factors, Fluorodeoxyglucose F18 pharmacokinetics, Glucose-6-Phosphatase metabolism, Insulin pharmacology, Monocytes diagnostic imaging, Monocytes metabolism, Tomography, Emission-Computed methods
- Abstract
While 18F-FDG labelling of monocytes would allow in vivo trafficking with positron emission tomography (PET), present methods suffer from poor retention of radioactivity. We investigated the feasibility of utilizing insulin for improved [18F]fluorodeoxyglucose (18F-FDG) labelling. Separated human monocytes and lymphocytes were labelled with 18F-FDG with or without 3 h insulin pre-incubation. Insulin had no effect on lymphocyte labelling (21.4+/-0.8% vs 20.8+/-1.1% efficiency, P=NS). However, for monocytes, insulin pre-incubation led to a 169+/-9% increase in labelling efficiency (19.3+/-4.1 vs 32.5+/-1.8, P<0.05), without significant effects on cell activation or viability. Moreover, while only 57.7+/-4.8% and 40.4+/-5.6% of the 18F-FDG was retained at 1 and 3 h for controls, the retention rate increased to 91.6+/-2.1% (P=0.01) and 86.5+/-1.9% (P<0.01) after insulin pre-incubation. Improved 18F-FDG retention was accompanied by a 70.3+/-7.4% decrease in glucose-6-phosphatase activity (P=0.02). PET imaging of rats showing hepatic ischaemia-reperfusion injury demonstrated higher liver uptake for monocytes labelled after insulin treatment. Thus, insulin improves monocytic 18F-FDG uptake and retention, and may provide a feasible labelling method for PET imaging.
- Published
- 2002
- Full Text
- View/download PDF
17. Suppression of GnRH gene expression in GT1-1 hypothalamic neuronal cells: action of protein kinase C.
- Author
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Sun W, Choe YS, Lee YJ, and Kim K
- Subjects
- Animals, Cell Line, Enzyme Inhibitors pharmacology, Genes, Reporter, Gonadotropin-Releasing Hormone genetics, Isoenzymes biosynthesis, Luciferases biosynthesis, Mice, Naphthalenes pharmacology, Promoter Regions, Genetic, Protein Kinase C biosynthesis, Protein Kinase C-alpha, Proto-Oncogene Proteins c-fos biosynthesis, Recombinant Fusion Proteins biosynthesis, Staurosporine pharmacology, Tetradecanoylphorbol Acetate pharmacology, Transfection, Gene Expression Regulation, Gonadotropin-Releasing Hormone biosynthesis, Hypothalamus metabolism, Neurons metabolism, Protein Kinase C metabolism, Transcription, Genetic drug effects
- Abstract
We attempted to elucidate molecular mechanisms of gonadotropin-releasing hormone (GnRH) gene regulation by the protein kinase C (PKC) pathway in GT1-1 cells. Activation of PKC with 12-tetra-decanoylphorbol-13-acetate (TPA) or inhibition with staurosporine or calphostin C down-regulated GnRH mRNA levels. A serial deletion mutant analysis revealed that this suppression was mediated by the proximal region (-187/-69) of the mouse GnRH promoter. TPA transiently induced c-fos mRNA, whereas staurosporine or calphostin C failed to do so. However, PKC inhibitors blocked the TPA-evoked c-fos induction. Over-expression of PKC alpha down-regulated GnRH promoter activity, indicating that PKC activation was sufficient to inhibit GnRH gene expression. These results suggest that both activation and inhibition of PKC decrease the GnRH gene expression in the GT1-1 cells probably through different signal cascade mechanisms.
- Published
- 1997
- Full Text
- View/download PDF
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