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Bini J, Gallezot JD, Li S, Lim K, Emery P, Kapinos M, Ropchan J, Nabulsi N, Jastreboff A, Huang Y, Carson R. RF12 | PSUN106 Quantifying Liver and Brain Levels of 11β-hydroxysteroid Dehydrogenase Type 1 in Obesity Using Positron Emission Tomography Imaging. J Endocr Soc 2022. [PMCID: PMC9624872 DOI: 10.1210/jendso/bvac150.062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Objectives Cortisol is known to promote adipocyte differentiation and maturation, and prolonged exposure to excess cortisol contributes to the development of obesity and metabolic dysregulation. The intracellular 11β-hydroxysteroid dehydrogenase type 1 (11β-HSD1) enzyme catalyzes the conversion of inactive cortisone to active cortisol. Recently, we demonstrated reduced brain 11β-HSD1 levels in vivo with increasing body mass index (BMI), using positron emission tomography (PET) radioligands [11C]- and [18F]AS2471907(1). PET imaging can simultaneously quantify uptake in multiple organs (e.g., liver/brain). [18F]AS2471907 has high uptake and specific binding in the brain and liver(2). Liver and brain 11β-HSD1 measured by PET imaging may help elucidate the roles of cortisol activation in the setting of metabolic dysregulation. Thus, we performed PET imaging studies to examine 11β-HSD1 levels in the liver and brain. Methods Nine individuals (5F/4M) with a range of BMIs (22.6-34.4 kg/m2) underwent a 90 min PET/CT acquisition with arterial plasma sampling after injection of [18F]AS2471907. Regions-of-interest (ROI) for the liver were manually drawn on a summed PET image (60-90 min). Seventeen brain ROIs were selected from the anatomical automatic labeling (AAL) template and applied to the dynamic PET images to generate time-activity-curves (TACs). Brain volume of distribution (VT, mL/cm3), the target tissue to plasma ratio of radioligand at equilibrium, was estimated for each ROI using the multilinear analysis-1 method with plasma input function. Mean whole-brain VT values were calculated by averaging all ROIs. Given the appearance of irreversible kinetics in the liver, Ki (min-1), the rate of irreversible tracer uptake, was calculated using the Patlak method. Results Qualitative brain and liver uptake was assessed by examining a summed PET image (SUV 60-90min). The parent fraction in plasma was 88±1% at 90 min, indicating negligible plasma radiolabeled-metabolites contributing the measured signal in the liver. Kinetic modeling estimates demonstrated decreasing whole brain VT with increasing BMI (R2=0.53), similar to our previously published study examining only brain in a larger cohort(1). Patlak methods provided good estimates of Ki. In an opposite manner from the brain, correlations seen in the liver using Ki were positively correlated with BMI (R2=0.57). Conclusions These preliminary studies suggest obesity is associated with increased 11β-HSD1 levels in the liver but decreased 11β-HSD1 levels in the brain. Clinically, liver specific 11β-HSD1 inhibitors may prove beneficial in treating metabolic sequalae of obesity such non-alcoholic fatty liver disease (NAFLD) by inhibiting activity of higher 11β-HSD1 levels. Further studies in NAFLD and obesity are necessary to determine appropriate populations that would benefit from 11β-HSD1 inhibitors and longitudinal in vivo PET imaging to help inform development of future therapeutics. References [1] Bini, et al, Molecular Imaging and Biology, 2020. [2] Bini, et al, IEEE Trans on Radiation and Plasma Medical Sciences, 2021 Presentation: Saturday, June 11, 2022 1:42 p.m. - 1:47 p.m., Sunday, June 12, 2022 12:30 p.m. - 2:30 p.m.
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Mecca AP, Rogers K, Jacobs Z, McDonald JW, Michalak HR, DellaGioia N, Zhao W, Hillmer AT, Nabulsi N, Lim K, Ropchan J, Huang Y, Matuskey D, Esterlis I, Carson RE, van Dyck CH. Effect of age on brain metabotropic glutamate receptor subtype 5 measured with [ 18F]FPEB PET. Neuroimage 2021; 238:118217. [PMID: 34052464 PMCID: PMC8378132 DOI: 10.1016/j.neuroimage.2021.118217] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/08/2021] [Accepted: 05/26/2021] [Indexed: 12/31/2022] Open
Abstract
OBJECTIVE Metabotropic glutamate receptor subtype 5 (mGluR5) is integral to the brain glutamatergic system and cognitive function. This study investigated whether aging is associated with decreased brain mGluR5 availability. METHODS Cognitively normal participants (n = 45), aged 18 to 84 years, underwent [18F]FPEB positron emission tomography scans to quantify brain mGluR5. Distribution volume (VT) was computed using a venous or arterial input function and equilibrium modeling from 90 to 120 min. In the primary analysis, the association between age and VT in the hippocampus and association cortex was evaluated using a linear mixed model. Exploratory analyses assessed the association between age and VT in multiple brain regions. The contribution of gray matter tissue alterations and partial volume effects to associations with age was also examined. RESULTS In the primary analysis, older age was associated with lower [18F]FPEB binding to mGluR5 (P = 0.026), whereas this association was not significant after gray matter masking or partial volume correction to account for age-related tissue loss. Post hoc analyses revealed an age-related decline in mGluR5 availability in the hippocampus of 4.5% per decade (P = 0.007) and a non-significant trend in the association cortex (P = 0.085). An exploratory analysis of multiple brain regions revealed broader inverse associations of age with mGluR5 availability, but not after partial volume correction. CONCLUSION Reductions in mGluR5 availability with age appear to be largely mediated by tissue loss. Quantification of [18F]FPEB binding to mGluR5 may expand our understanding of age-related molecular changes and the relationship with brain tissue loss.
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Affiliation(s)
- Adam P Mecca
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.
| | - Kelly Rogers
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Zachary Jacobs
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Julia W McDonald
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Hannah R Michalak
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Nicole DellaGioia
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Wenzhen Zhao
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Ansel T Hillmer
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Nabeel Nabulsi
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Keunpoong Lim
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Jim Ropchan
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Yiyun Huang
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - David Matuskey
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA; Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
| | - Irina Esterlis
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Richard E Carson
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Christopher H van Dyck
- Alzheimer's Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT, 06514, USA; Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Department of Neurology, Yale University School of Medicine, New Haven, CT, USA
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Salardini A, Hillmer AT, Mecca AP, Hashemi‐Aghdam A, Laltoo E, Savoia S, O'Dell RS, Harris JE, Godek TA, Nabulsi NB, Lim K, Ropchan JR, Huang Y, Cosgrove K, Carson RE, Strittmatter SM, van Dyck CH. PBR28 Brain PET imaging with lipopolysaccharide challenge for the study of microglia function in Alzheimer’s disease. Alzheimers Dement 2020. [DOI: 10.1002/alz.037792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Salardini A, Hillmer AT, Mecca AP, Hashemi‐Aghdam A, Laltoo E, Savoia S, O'Dell RS, Harris JE, Godek TA, Nabulsi NB, Lim K, Ropchan JR, Huang Y, Cosgrove K, Carson RE, Strittmatter SM, van Dyck CH. 11C‐PBR28 brain PET imaging with lipopolysaccharide challenge for the study of microglia function in Alzheimer’s disease. Alzheimers Dement 2020. [DOI: 10.1002/alz.043584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Tran TT, Gallezot JD, Jilaveanu LB, Zito C, Turcu G, Lim K, Nabulsi N, Huang H, Huttner A, Kluger HM, Chiang VL, Carson R. [ 11C]Methionine and [ 11C]PBR28 as PET Imaging Tracers to Differentiate Metastatic Tumor Recurrence or Radiation Necrosis. Mol Imaging 2020; 19:1536012120968669. [PMID: 33147119 PMCID: PMC7649862 DOI: 10.1177/1536012120968669] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Purpose: As stereotactic radiosurgery (SRS) and immunotherapy are increasingly used to treat brain metastases, incidence of radiation necrosis (RN) is consequently rising. Differentiating tumor regrowth (TR) from RN is vital in management but difficult to assess using MRI. We hypothesized that tumor methionine levels would be elevated given increased metabolism and high amino acid uptake, whereas RN would increase inflammation marked by upregulated translocator protein (PBR-TSPO), which can be quantified with specific PET tracers. Procedures: We performed a feasibility study to prospectively evaluate [11C]methionine and [11C]PBR28 using PET in 5 patients with 7 previously SRS-treated brain metastases demonstrating regrowth to differentiate TR from RN. Results: Sequential imaging with dual tracers was well-tolerated. [11C]methionine was accurate for detecting pathologically confirmed TR in 7/7 lesions, whereas [11C]PBR28 was only accurate in 3/7 lesions. Tumor PBR-TSPO expression was elevated in both melanoma and lung cancer cells, contributing to lack of specificity of [11C]PBR28-PET. Conclusion: Sequential use of PET tracers is safe and effective. [11C]Methionine was a reliable TR marker, but [11C]PBR28 was not a reliable marker of RN. Studies are needed to determine the causes of post-radiation inflammation and identify specific markers of RN to improve diagnostic imaging.
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Affiliation(s)
- Thuy T Tran
- Yale School of Medicine and Yale Cancer Center, 12228Yale University, New Haven, CT, USA
| | - Jean-Dominique Gallezot
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, 12228Yale University, New Haven, CT, USA
| | - Lucia B Jilaveanu
- Yale School of Medicine and Yale Cancer Center, 12228Yale University, New Haven, CT, USA
| | - Christopher Zito
- Department of Biology, School of Health and Natural Sciences, 8515University of Saint Joseph, West Hartford, CT, USA
| | - Gabriela Turcu
- Yale School of Medicine and Yale Cancer Center, 12228Yale University, New Haven, CT, USA
| | - Keunpoong Lim
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, 12228Yale University, New Haven, CT, USA
| | - Nabeel Nabulsi
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, 12228Yale University, New Haven, CT, USA
| | - Henry Huang
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, 12228Yale University, New Haven, CT, USA
| | - Anita Huttner
- Department of Pathology, Yale School of Medicine, 12228Yale University, New Haven, CT, USA
| | - Harriet M Kluger
- Yale School of Medicine and Yale Cancer Center, 12228Yale University, New Haven, CT, USA
| | - Veronica L Chiang
- Yale School of Medicine and Yale Cancer Center, 12228Yale University, New Haven, CT, USA.,Department of Neurosurgery, Yale School of Medicine, 12228Yale University, New Haven, CT, USA
| | - Richard Carson
- Department of Radiology and Biomedical Imaging, Yale School of Medicine, 12228Yale University, New Haven, CT, USA
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Mecca AP, McDonald JW, Michalak HR, Godek TA, Harris JE, Pugh EA, Kemp EC, Chen MK, Salardini A, Nabulsi NB, Lim K, Huang Y, Carson RE, Strittmatter SM, van Dyck CH. PET imaging of mGluR5 in Alzheimer's disease. Alzheimers Res Ther 2020; 12:15. [PMID: 31954399 PMCID: PMC6969979 DOI: 10.1186/s13195-020-0582-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 01/05/2020] [Indexed: 12/20/2022]
Abstract
BACKGROUND Metabotropic glutamate subtype 5 receptors (mGluR5) modulate synaptic transmission and may constitute an important therapeutic target in Alzheimer's disease (AD) by mediating the synaptotoxic action of amyloid-β oligomers. We utilized the positron emission tomography (PET) radioligand [18F]FPEB to investigate mGluR5 binding in early AD. METHODS Sixteen individuals with amnestic mild cognitive impairment (MCI) due to AD or mild AD dementia who were positive for brain amyloid were compared to 15 cognitively normal (CN) participants who were negative for brain amyloid. Diagnostic groups were well balanced for age, sex, and education. Dynamic PET scans were acquired for 60 min, starting at 60 min after the initial administration of up to 185 MBq of [18F]FPEB using a bolus-plus-constant-infusion method (Kbol = 190 min). Equilibrium modeling with a cerebellum reference region was used to estimate [18F]FPEB binding (BPND) to mGluR5. Analyses were performed with and without corrections for gray matter atrophy and partial volume effects. RESULTS Linear mixed model analysis demonstrated a significant effect of group (p = 0.011) and the group × region interaction (p = 0.0049) on BPND. Post hoc comparisons revealed a significant reduction (43%) in mGluR5 binding in the hippocampus of AD (BPND = 0.76 ± 0.41) compared to CN (BPND = 1.34 ± 0.58, p = 0.003, unpaired t test) participants, and a nonsignificant trend for a reduction in a composite association cortical region in AD (BPND = 1.57 ± 0.25) compared to CN (BPND = 1.86 ± 0.63, p = 0.093) participants. Exploratory analyses suggested additional mGluR5 reductions in the entorhinal cortex and parahippocampal gyrus in the AD group. In the overall sample, hippocampal mGluR5 binding was associated with episodic memory scores and global function. CONCLUSIONS [18F]FPEB-PET revealed reductions in hippocampal mGluR5 binding in early AD. Quantification of mGluR5 binding in AD may expand our understanding of AD pathogenesis and accelerate the development of novel biomarkers and treatments.
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Affiliation(s)
- Adam P. Mecca
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Julia W. McDonald
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Hannah R. Michalak
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Tyler A. Godek
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Joanna E. Harris
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Erika A. Pugh
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Emily C. Kemp
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
| | - Ming-Kai Chen
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Arash Salardini
- Department of Neurology, Yale University School of Medicine, New Haven, CT USA
| | - Nabeel B. Nabulsi
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Keunpoong Lim
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Yiyun Huang
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Richard E. Carson
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT USA
| | - Stephen M. Strittmatter
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT USA
- Department of Neurology, Yale University School of Medicine, New Haven, CT USA
- CNNR Program, Yale University School of Medicine, 295 Congress Avenue, Ste 431-435, New Haven, CT USA
| | - Christopher H. van Dyck
- Alzheimer’s Disease Research Unit, Yale University School of Medicine, One Church Street, 8th Floor, New Haven, CT 06510 USA
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT USA
- Department of Neurology, Yale University School of Medicine, New Haven, CT USA
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Bini J, Sanchez-Rangel E, Gallezot JD, Naganawa M, Nabulsi N, Lim K, Najafzadeh S, Shirali A, Ropchan J, Matuskey D, Huang Y, Herold KC, Harris PE, Sherwin RS, Carson RE, Cline GW. PET Imaging of Pancreatic Dopamine D 2 and D 3 Receptor Density with 11C-(+)-PHNO in Type 1 Diabetes. J Nucl Med 2019; 61:570-576. [PMID: 31601695 DOI: 10.2967/jnumed.119.234013] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Type 1 diabetes mellitus (T1DM) has traditionally been characterized by a complete destruction of β-cell mass (BCM); however, there is growing evidence of possible residual BCM present in T1DM. Given the absence of in vivo tools to measure BCM, routine clinical measures of β-cell function (e.g., C-peptide release) may not reflect BCM. We previously demonstrated the potential utility of PET imaging with the dopamine D2 and D3 receptor agonist 3,4,4a,5,6,10b-hexahydro-2H-naphtho[1,2-b][1,4]oxazin-9-ol (11C-(+)-PHNO) to differentiate between healthy control (HC) and T1DM individuals. Methods: Sixteen individuals participated (10 men, 6 women; 9 HCs, 7 T1DMs). The average duration of diabetes was 18 ± 6 y (range, 14-30 y). Individuals underwent PET/CT scanning with a 120-min dynamic PET scan centered on the pancreas. One- and 2-tissue-compartment models were used to estimate pancreas and spleen distribution volume. Reference region approaches (spleen as reference) were also investigated. Quantitative PET measures were correlated with clinical outcome measures. Immunohistochemistry was performed to examine colocalization of dopamine receptors with endocrine hormones in HC and T1DM pancreatic tissue. Results: C-peptide release was not detectable in any T1DM individuals, whereas proinsulin was detectable in 3 of 5 T1DM individuals. Pancreas SUV ratio minus 1 (SUVR-1) (20-30 min; spleen as reference region) demonstrated a statistically significant reduction (-36.2%) in radioligand binding (HCs, 5.6; T1DMs, 3.6; P = 0.03). Age at diagnosis correlated significantly with pancreas SUVR-1 (20-30 min) (R 2 = 0.67, P = 0.025). Duration of diabetes did not significantly correlate with pancreas SUVR-1 (20-30 min) (R 2 = 0.36, P = 0.16). Mean acute C-peptide response to arginine at maximal glycemic potentiation did not significantly correlate with SUVR-1 (20-30 min) (R 2 = 0.57, P = 0.05), nor did mean baseline proinsulin (R 2 = 0.45, P = 0.10). Immunohistochemistry demonstrated colocalization of dopamine D3 receptor and dopamine D2 receptor in HCs. No colocalization of the dopamine D3 receptor or dopamine D2 receptor was seen with somatostatin, glucagon, or polypeptide Y. In a separate T1DM individual, no immunostaining was seen with dopamine D3 receptor, dopamine D2 receptor, or insulin antibodies, suggesting that loss of endocrine dopamine D3 receptor and dopamine D2 receptor expression accompanies loss of β-cell functional insulin secretory capacity. Conclusion: Thirty-minute scan durations and SUVR-1 provide quantitative outcome measures for 11C-(+)-PHNO, a dopamine D3 receptor-preferring agonist PET radioligand, to differentiate BCM in T1DM and HCs.
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Affiliation(s)
- Jason Bini
- PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Elizabeth Sanchez-Rangel
- Department of Internal Medicine, Division of Endocrinology, Yale University School of Medicine, New Haven, Connecticut; and
| | | | - Mika Naganawa
- PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Nabeel Nabulsi
- PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Keunpoong Lim
- PET Center, Yale University School of Medicine, New Haven, Connecticut
| | | | - Anupama Shirali
- PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Jim Ropchan
- PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - David Matuskey
- PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Yiyun Huang
- PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Kevan C Herold
- Department of Internal Medicine, Division of Endocrinology, Yale University School of Medicine, New Haven, Connecticut; and
| | - Paul E Harris
- Department of Medicine, Division of Endocrinology, Columbia University, New York, New York
| | - Robert S Sherwin
- Department of Internal Medicine, Division of Endocrinology, Yale University School of Medicine, New Haven, Connecticut; and
| | - Richard E Carson
- PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Gary W Cline
- Department of Internal Medicine, Division of Endocrinology, Yale University School of Medicine, New Haven, Connecticut; and
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Deng G, Ma C, Zhao H, Zhang S, Liu J, Liu F, Chen Z, Chen AT, Yang X, Avery J, Zou P, Du F, Lim KP, Holden D, Li S, Carson RE, Huang Y, Chen Q, Kimberly WT, Simard JM, Sheth KN, Zhou J. Anti-edema and antioxidant combination therapy for ischemic stroke via glyburide-loaded betulinic acid nanoparticles. Am J Cancer Res 2019; 9:6991-7002. [PMID: 31660082 PMCID: PMC6815966 DOI: 10.7150/thno.35791] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 07/30/2019] [Indexed: 12/19/2022] Open
Abstract
Stroke is a deadly disease without effective pharmacotherapies, which is due to two major reasons. First, most therapeutics cannot efficiently penetrate the brain. Second, single agent pharmacotherapy may be insufficient and effective treatment of stroke requires targeting multiple complementary targets. Here, we set to develop single component, multifunctional nanoparticles (NPs) for targeted delivery of glyburide to the brain for stroke treatment. Methods: To characterize the brain penetrability, we radiolabeled glyburide, intravenously administered it to stroke- bearing mice, and determined its accumulation in the brain using positron emission tomography-computed tomography (PET/CT). To identify functional nanomaterials to improve drug delivery to the brain, we developed a chemical extraction approach and tested it for isolation of nanomaterials from E. ulmoides, a medicinal herb. To assess the therapeutic benefits, we synthesized glyburide-loaded NPs and evaluated them in stroke- bearing mice. Results: We found that glyburide has a limited ability to penetrate the ischemic brain. We identified betulinic acid (BA) capable of forming NPs, which, after intravenous administration, efficiently penetrate the brain and significantly reduce ischemia-induced infarction as an antioxidant agent. We demonstrated that BA NPs enhance delivery of glyburide, leading to therapeutic benefits significantly greater than those achieved by either glyburide or BA NPs. Conclusion: This study suggests a new direction to identify functional nanomaterials and a simple approach to achieving anti-edema and antioxidant combination therapy. The resulting glyburide- loaded BA NPs may be translated into clinical applications to improve clinical management of stroke.
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Mecca AP, Chen MK, Godek TA, Harris JE, Bartlett HH, Toyonaga T, Naganawa M, Salardini A, Arnsten AF, Nabulsi NB, Lim K, Najafzadeh S, Ropchan JR, Huang Y, Carson RE, Strittmatter SM, van Dyck CH. IC-P-140: ASSOCIATION BETWEEN MGLUR5 AND SYNAPTIC DENSITY: A MULTI-TRACER STUDY IN HEALTHY AGING AND ALZHEIMER'S DISEASE. Alzheimers Dement 2019. [DOI: 10.1016/j.jalz.2019.06.4254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Mecca AP, Chen MK, Godek TA, Harris JE, Bartlett HH, Toyonaga T, Naganawa M, Salardini A, Arnsten AF, Nabulsi NB, Lim K, Najafzadeh S, Ropchan JR, Huang Y, Carson RE, Strittmatter SM, van Dyck CH. P2-349: ASSOCIATION BETWEEN MGLUR5 AND SYNAPTIC DENSITY: A MULTI-TRACER STUDY OF HEALTHY AGING AND ALZHEIMER'S DISEASE. Alzheimers Dement 2019. [DOI: 10.1016/j.jalz.2019.06.2756] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Lim KP, Yong SL. Pseudohypoparathyroidism: A case of hypocalcemia and hypothyroidism diagnosed during the postpartum period. Malays Fam Physician 2019; 14:31-34. [PMID: 31289630 PMCID: PMC6612271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
We describe a 29-year-old Para 1 post-Emergency Lower Segment Caesarean Section (EMLSCS) for fetal distress and Preterm Rupture of the Membrane (PROM) referred by the Obstetric team for persistent bradycardia. She had the typical features of Albright's Hereditary Osteodystrophy (AHO). The laboratory investigation revealed hypocalcemia, hyperphosphatemia with a high Parathyroid hormone (PTH) level and low free Thyroxine 4 (fT4) with high Thyroid Stimulating Hormone (TSH). The patient was diagnosed with Pseudohypoparathyroidism (PHP) Type 1A associated with TSH resistance based on the somatic features of AHO present as well as biochemical and radiological abnormalities.
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Affiliation(s)
- K P Lim
- MRCP (UK), Department of Medicine, Hospital Tengku Ampuan Rahimah Selangor, Malaysia.
| | - S L Yong
- MRCP (UK), Department of Medicine, Hospital Tengku Ampuan Rahimah Selangor, Malaysia
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Naganawa M, Lim K, Nabulsi NB, Lin SF, Labaree D, Ropchan J, Herold KC, Huang Y, Harris P, Ichise M, Cline GW, Carson RE. Evaluation of Pancreatic VMAT2 Binding with Active and Inactive Enantiomers of [ 18F]FP-DTBZ in Healthy Subjects and Patients with Type 1 Diabetes. Mol Imaging Biol 2019; 20:835-845. [PMID: 29468404 DOI: 10.1007/s11307-018-1170-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Previous studies demonstrated the utility of [18F]fluoropropyl-(+)-dihydrotetrabenazine ([18F]FP-(+)-DTBZ) as a positron emission tomography (PET) radiotracer for the vesicular monoamine transporter type 2 (VMAT2) to quantify beta cell mass in healthy control (HC) and type 1 diabetes mellitus (T1DM) groups. Quantification of specific binding requires measurement of non-displaceable uptake. Our goal was to identify a reference tissue (renal cortex or spleen) to quantify pancreatic non-specific binding of [18F]FP-(+)-DTBZ with the inactive enantiomer, [18F]FP-(-)-DTBZ. This was the first human study of [18F]FP-(-)-DTBZ. PROCEDURES Six HCs and four T1DM patients were scanned on separate days after injection of [18F]FP-(+)-DTBZ or [18F]FP-(-)-DTBZ. Distribution volumes (VT) and standardized uptake values (SUVs) were compared between groups. Three methods for calculation of non-displaceable uptake (VND) or reference SUV were applied: (1) use of [18F]FP-(+)-DTBZ reference VT as VND, assuming VND is uniform across organs; (2) use of [18F]FP-(-)-DTBZ pancreatic VT as VND, assuming that VND is uniform between enantiomers in the pancreas; and (3) use of a scaled [18F]FP-(+)-DTBZ reference VT as VND, assuming that a ratio of non-displaceable uptake between organs is uniform between enantiomers. Group differences in VT (or SUV), binding potential (BPND), or SUV ratio (SUVR) were estimated using these three methods. RESULTS [18F]FP-(-)-DTBZ VT values were different among organs, and VT(+) and VT(-) were also different in the renal cortex and spleen. Method 3 with the spleen to estimate VND (or reference SUV) gave the highest non-displaceable uptake and the largest HC vs. T1DM group differences. Significant group differences were also observed in VT (or SUV) with method 1 using spleen. SUV was affected by differences in the input function between groups and between enantiomers. CONCLUSIONS Non-displaceable uptake was different among organs and between enantiomers. Use of scaled spleen VT values for VND is a suitable method for quantification of VMAT2 in the pancreas.
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Affiliation(s)
- Mika Naganawa
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA.
| | - Keunpoong Lim
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA
| | - Nabeel B Nabulsi
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA
| | - Shu-Fei Lin
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA
| | - David Labaree
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA
| | - Jim Ropchan
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA
| | - Kevan C Herold
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA
| | - Yiyun Huang
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA
| | | | | | - Gary W Cline
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA
| | - Richard E Carson
- Yale University, P.O. Box 208048, New Haven, CT, 06520-8048, USA
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13
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Bini J, Naganawa M, Nabulsi N, Huang Y, Ropchan J, Lim K, Najafzadeh S, Herold KC, Cline GW, Carson RE. Evaluation of PET Brain Radioligands for Imaging Pancreatic β-Cell Mass: Potential Utility of 11C-(+)-PHNO. J Nucl Med 2018; 59:1249-1254. [PMID: 29371405 DOI: 10.2967/jnumed.117.197285] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 12/07/2017] [Indexed: 12/21/2022] Open
Abstract
Type 1 diabetes mellitus (T1DM) is characterized by a loss of β-cells in the islets of Langerhans of the pancreas and subsequent deficient insulin secretion in response to hyperglycemia. Development of an in vivo test to measure β-cell mass (BCM) would greatly enhance the ability to track diabetes therapies. β-cells and neurologic tissues have common cellular receptors and transporters, therefore, we screened brain radioligands for their ability to identify β-cells. Methods: We examined a β-cell gene atlas for endocrine pancreas receptor targets and cross-referenced these targets with brain radioligands that were available at our institution. Twelve healthy control subjects and 2 T1DM subjects underwent dynamic PET/CT scans with 6 tracers. Results: The D2/D3 receptor agonist radioligand 11C-(+)-4-propyl-9-hydroxynaphthoxazine (PHNO) was the only radioligand to demonstrate sustained uptake in the pancreas with high contrast versus abdominal organs such as the kidneys, liver, and spleen, based on the first 30 min of data. Mean SUV from 20 to 30 min demonstrated high uptake of 11C-(+)-PHNO in healthy controls (SUV, 13.8) with a 71% reduction in a T1DM subject with undetectable levels of C-peptide (SUV, 4.0) and a 20% reduction in a T1DM subject with fasting C-peptide level of 0.38 ng/mL (SUV, 11.0). SUV in abdominal organs outside the pancreas did not show measurable differences between the control and T1DM subjects, suggesting that the changes in SUV of 11C-(+)-PHNO may be specific to changes in the pancreas between healthy controls and T1DM subjects. When D3 and D2 antagonists were used in nonhuman primates, specific pancreatic binding (SUVR-1) of 11C-PHNO was reduced by 57% and 38%, respectively. Conclusion:11C-(+)-PHNO is a potential marker of BCM, with 2:1 binding of D3 receptors over D2 receptors. Further in vitro and in vivo studies to establish D2/D3 receptor specificity to β-cells is warranted to characterize 11C-(+)-PHNO as a candidate for clinical measurement of BCM in healthy control and diabetic subjects.
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Affiliation(s)
- Jason Bini
- PET Center, Yale University School of Medicine, New Haven, CT .,Department of Biomedical Engineering, Yale University, New Haven, CT; and
| | - Mika Naganawa
- PET Center, Yale University School of Medicine, New Haven, CT
| | - Nabeel Nabulsi
- PET Center, Yale University School of Medicine, New Haven, CT
| | - Yiyun Huang
- PET Center, Yale University School of Medicine, New Haven, CT
| | - Jim Ropchan
- PET Center, Yale University School of Medicine, New Haven, CT
| | - Keunpoong Lim
- PET Center, Yale University School of Medicine, New Haven, CT
| | | | - Kevan C Herold
- Department of Immunobiology and Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Gary W Cline
- Department of Immunobiology and Internal Medicine, Yale University School of Medicine, New Haven, CT
| | - Richard E Carson
- PET Center, Yale University School of Medicine, New Haven, CT.,Department of Biomedical Engineering, Yale University, New Haven, CT; and
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14
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Bhatt S, Hillmer AT, Nabulsi N, Matuskey D, Lim K, Lin SF, Esterlis I, Carson RE, Huang Y, Cosgrove KP. Evaluation of (-)-[ 18 F]Flubatine-specific binding: Implications for reference region approaches. Synapse 2017; 72. [PMID: 29105121 DOI: 10.1002/syn.22016] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 10/13/2017] [Accepted: 10/31/2017] [Indexed: 11/05/2022]
Abstract
We aimed to characterize changes in binding of (-)-[18 F]Flubatine to α4 β2 *-nicotinic acetylcholine receptors (α4 β2 *-nAChRs) during a tobacco cigarette smoking challenge. Displacement of (-)-[18 F]Flubatine throughout the brain was quantified as change in (-)-[18 F]Flubatine distribution volume (VT ), with particular emphasis on regions with low VT . Three tobacco smokers were imaged with positron emission tomography (PET) during a 210 min bolus-plus-constant infusion of (-)-[18 F]Flubatine. A tobacco cigarette was smoked in the PET scanner ∼125 min after the start of (-)-[18 F]Flubatine injection. Equilibrium analysis was used to estimate VT at baseline (90-120 min) and after cigarette challenge (180-210 min), at the time of greatest receptor occupancy by nicotine. Smoking reduced VT by 21 ± 9% (average ±SD) in corpus callosum, 17 ± 9% in frontal cortex, 36 ± 11% in cerebellum, and 22 ± 10% in putamen. The finding of displaceable (-)-[18 F]Flubatine binding throughout the brain is an important consideration for reference region-based quantification approaches with this tracer. We observed displacement of (-)-[18 F]Flubatine binding to α4 β2 *-nicotinic acetylcholine receptors in corpus callosum by a tobacco cigarette challenge. We conclude that reference region approaches utilizing corpus callosum should first perform careful characterization of displaceable (-)-[18 F]Flubatine binding and nondisplaceable kinetics in this putative reference region.
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Affiliation(s)
- Shivani Bhatt
- Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, Connecticut.,Yale PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Ansel T Hillmer
- Yale PET Center, Yale University School of Medicine, New Haven, Connecticut.,Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut.,Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Nabeel Nabulsi
- Yale PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - David Matuskey
- Yale PET Center, Yale University School of Medicine, New Haven, Connecticut.,Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut.,Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
| | - Keunpoong Lim
- Yale PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Shu-Fei Lin
- Yale PET Center, Yale University School of Medicine, New Haven, Connecticut
| | - Irina Esterlis
- Yale PET Center, Yale University School of Medicine, New Haven, Connecticut.,Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut.,West Haven VA Hospital, National Center for PTSD, West Haven, Connecticut
| | - Richard E Carson
- Yale PET Center, Yale University School of Medicine, New Haven, Connecticut.,Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut
| | - Yiyun Huang
- Yale PET Center, Yale University School of Medicine, New Haven, Connecticut.,Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut
| | - Kelly P Cosgrove
- Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, Connecticut.,Yale PET Center, Yale University School of Medicine, New Haven, Connecticut.,Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, Connecticut.,Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut.,West Haven VA Hospital, National Center for PTSD, West Haven, Connecticut
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15
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Naganawa M, Lin SF, Lim K, Labaree D, Ropchan J, Harris P, Huang Y, Ichise M, Carson RE, Cline GW. Evaluation of pancreatic VMAT2 binding with active and inactive enantiomers of 18F-FP-DTBZ in baboons. Nucl Med Biol 2016; 43:743-751. [PMID: 27673755 DOI: 10.1016/j.nucmedbio.2016.08.018] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Revised: 08/04/2016] [Accepted: 08/28/2016] [Indexed: 01/09/2023]
Abstract
INTRODUCTION 18F-Fluoropropyl-(+)-dihydrotetrabenazine (18F-FP-(+)-DTBZ) is a vesicular monoamine transporter type 2 (VMAT2) radiotracer for positron emission tomography (PET) imaging to quantify human β-cell mass. Renal cortex and spleen have been suggested as reference regions, however, little is known about 18F-FP-(+)-DTBZ binding in these regions including the fraction of radiometabolite. We compared the kinetics of 18F-FP-(+)-DTBZ and its inactive enantiomer 18F-FP-(-)-DTBZ in baboons, estimated the non-displaceable binding (VND) of the tracers, and used ex vivo studies to measure radiometabolite fractions. METHODS PET scans were conducted for up to 4h with (+) and (-) enantiomers. Displacement experiments using unlabeled (+) and (-) enantiomers of FP-DTBZ and fluvoxamine (to evaluate sigma-1 receptor binding) were performed. SUV curves were used to calculate displacement values in the pancreas, renal cortex, and spleen. Distribution volumes (VT) were computed, and three approaches for calculation of VND were compared: (1) 18F-FP-(+)-DTBZ reference VT, (2) 18F-FP-(-)-DTBZ pancreatic VT, and (3) a scaled 18F-FP-(+)-DTBZ reference VT values. Ex vivo study was conducted to measure radiometabolite fraction in homogenized tissue samples from baboons at 90min post-injection. RESULTS Spleen uptake was lowest for both tracers. Highest uptake was in the pancreas with 18F-FP-(+)-DTBZ and renal cortex with 18F-FP-(-)-DTBZ. Substantial displacement effect was observed only with unlabeled FP-(+)-DTBZ in the 18F-FP-(+)-DTBZ studies. Radiometabolite fraction was higher in the renal cortex than the spleen. Approaches (1) and (3) with spleen to estimate VND provided lowest inter-subject variability of BPND. CONCLUSIONS VT differences among organs and between enantiomers indicated that scaling of reference region values is needed for quantification of VMAT2 binding in the pancreas with 18F-FP-(+)-DTBZ. Since the kidney PET signal has greater partial volume averaging and more radiometabolites, the spleen was considered a more practical candidate for use as a scaled-reference region in the quantification of 18F-FP-(+)-DTBZ in the pancreas.
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Affiliation(s)
- Mika Naganawa
- Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT, United States, 06520
| | - Shu-Fei Lin
- Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT, United States, 06520
| | - Keunpoong Lim
- Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT, United States, 06520
| | - David Labaree
- Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT, United States, 06520
| | - Jim Ropchan
- Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT, United States, 06520
| | - Paul Harris
- Columbia University, New York, NY, United States
| | - Yiyun Huang
- Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT, United States, 06520
| | | | - Richard E Carson
- Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT, United States, 06520
| | - Gary W Cline
- Yale University, 801 Howard Avenue, PO Box 208048, New Haven, CT, United States, 06520
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16
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Abstract
The traditional techniques involving an oblique tunnel or triangular wedge resection to approach a central or mixed-type physeal bar are hindered by poor visualisation of the bar. This may be overcome by a complete transverse osteotomy at the metaphysis near the growth plate or a direct vertical approach to the bar. Ilizarov external fixation using small wires allows firm fixation of the short physis-bearing fragment, and can also correct an associated angular deformity and permit limb lengthening. We accurately approached and successfully excised ten central- or mixed-type bars; six in the distal femur, two in the proximal tibia and two in the distal tibia, without damaging the uninvolved physis, and corrected the associated angular deformity and leg-length discrepancy. Callus formation was slightly delayed because of periosteal elevation and stretching during resection of the bar. The resultant resection of the bar was satisfactory in seven patients and fair in three as assessed using a by a modified Williamson-Staheli classification.
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Affiliation(s)
- H T Kim
- Pusan National University, 1Ga-10, Ami-Dong, Seo-Gu Busan, 602-739, Korea
| | - K P Lim
- Pusan National University, 1Ga-10, Ami-Dong, Seo-Gu Busan, 602-739, Korea
| | - J H Jang
- Pusan National University, 1Ga-10, Ami-Dong, Seo-Gu Busan, 602-739, Korea
| | - T Y Ahn
- Pusan National University, 1Ga-10, Ami-Dong, Seo-Gu Busan, 602-739, Korea
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17
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Park E, Sullivan JM, Planeta B, Gallezot JD, Lim K, Lin SF, Ropchan J, McCarthy TJ, Ding YS, Morris ED, Williams WA, Huang Y, Carson RE. Test-retest reproducibility of the metabotropic glutamate receptor 5 ligand [¹⁸F]FPEB with bolus plus constant infusion in humans. Eur J Nucl Med Mol Imaging 2015; 42:1530-41. [PMID: 26044120 DOI: 10.1007/s00259-015-3094-6] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 05/21/2015] [Indexed: 12/12/2022]
Abstract
PURPOSE [(18)F]FPEB is a promising PET radioligand for the metabotropic glutamate receptor 5 (mGluR5), a potential target for the treatment of neuropsychiatric diseases. The purpose of this study was to evaluate the test-retest reproducibility of [(18)F]FPEB in the human brain. METHODS Seven healthy male subjects were scanned twice, 3 - 11 weeks apart. Dynamic data were acquired using bolus plus infusion of 162 ± 32 MBq [(18)F]FPEB. Four methods were used to estimate volume of distribution (V T): equilibrium analysis (EQ) using arterial (EQA) or venous input data (EQV), MA1, and a two-tissue compartment model (2 T). Binding potential (BP ND) was also estimated using cerebellar white matter (CWM) or gray matter (CGM) as the reference region using EQ, 2 T and MA1. Absolute test-retest variability (aTRV) of V T and BP ND were calculated for each method. Venous blood measurements (C V) were compared with arterial input (C A) to examine their usability in EQ analysis. RESULTS Regional V T estimated by the four methods displayed a high degree of agreement (r (2) ranging from 0.83 to 0.99 among the methods), although EQA and EQV overestimated V T by a mean of 9 % and 7 %, respectively, compared to 2 T. Mean values of aTRV of V T were 11 % by EQA, 12 % by EQV, 14 % by MA1 and 14 % by 2 T. Regional BP ND also agreed well among the methods and mean aTRV of BP ND was 8 - 12 % (CWM) and 7 - 9 % (CGM). Venous and arterial blood concentrations of [(18)F]FPEB were well matched during equilibrium (C V = 1.01 · C A, r (2) = 0.95). CONCLUSION [(18)F]FPEB binding shows good TRV with minor differences among analysis methods. Venous blood can be used as an alternative for input function measurement instead of arterial blood in EQ analysis. Thus, [(18)F]FPEB is an excellent PET imaging tracer for mGluR5 in humans.
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Affiliation(s)
- Eunkyung Park
- PET Center, Department of Diagnostic Radiology, Yale School of Medicine, 801 Howard Avenue, PO Box 208048, New Haven, CT, 06520-8048, USA,
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18
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Stathakis A, Lim KP, Boan P, Lavender M, Wrobel J, Musk M, Heath CH. Penicillium marneffei infection in a lung transplant recipient. Transpl Infect Dis 2015; 17:429-34. [PMID: 25809145 DOI: 10.1111/tid.12377] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Revised: 02/08/2015] [Accepted: 02/16/2015] [Indexed: 11/28/2022]
Abstract
Penicillium marneffei is a thermally dimorphic fungus that can cause severe opportunistic infections in endemic regions of Southeast Asia, particularly in individuals infected with human immunodeficiency virus-1, but has rarely been reported in solid organ transplant recipients. Herein, we report the first case, to our knowledge, of P. marneffei infection in a lung transplant recipient, occurring in a 41-year-old woman 28 months post lung transplantation, after recent travel to Vietnam. We have reviewed the literature to derive some management principles for this rare infection in this clinical context. The number of P. marneffei infections in transplant recipients may increase, as a result of increasing rates of transplantation and travel to endemic areas.
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Affiliation(s)
- A Stathakis
- Department of Microbiology and Infectious Diseases, Royal Perth Hospital, Perth, Western Australia, Australia
| | - K P Lim
- WA Advanced Lung Disease and Lung Transplant Unit, Royal Perth Hospital, Perth, Western Australia, Australia
| | - P Boan
- Department of Microbiology and Infectious Diseases, Royal Perth Hospital, Perth, Western Australia, Australia
| | - M Lavender
- WA Advanced Lung Disease and Lung Transplant Unit, Royal Perth Hospital, Perth, Western Australia, Australia
| | - J Wrobel
- WA Advanced Lung Disease and Lung Transplant Unit, Royal Perth Hospital, Perth, Western Australia, Australia
| | - M Musk
- WA Advanced Lung Disease and Lung Transplant Unit, Royal Perth Hospital, Perth, Western Australia, Australia
| | - C H Heath
- Department of Microbiology and Infectious Diseases, Royal Perth Hospital, Perth, Western Australia, Australia.,Department of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia
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Park E, Gallezot JD, Delgadillo A, Liu S, Planeta B, Lin SF, O'Connor KC, Lim K, Lee JY, Chastre A, Chen MK, Seneca N, Leppert D, Huang Y, Carson RE, Pelletier D. (11)C-PBR28 imaging in multiple sclerosis patients and healthy controls: test-retest reproducibility and focal visualization of active white matter areas. Eur J Nucl Med Mol Imaging 2015; 42:1081-92. [PMID: 25833352 DOI: 10.1007/s00259-015-3043-4] [Citation(s) in RCA: 69] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 03/08/2015] [Indexed: 11/28/2022]
Abstract
PURPOSE Activated microglia play a key role in inflammatory demyelinating injury in multiple sclerosis (MS). Microglial activation can be measured in vivo using a positron emission tomography (PET) ligand (11)C-PBR28. We evaluated the test-retest variability (TRV) and lesion detectability of (11)C-PBR28 binding in MS subjects and healthy controls (HCs) with high-resolution PET. METHODS Four clinically and radiologically stable relapsing-remitting MS subjects (age 41 ± 7 years, two men/two women) and four HCs (age 42 ± 8 years, 2 two men/two women), matched for translocator protein genotype [two high- and two medium-affinity binders according to DNA polymorphism (rs6971) in each group], were studied for TRV. Another MS subject (age 41 years, male) with clinical and radiological activity was studied for lesion detectability. Dynamic data were acquired over 120 min after injection of 634 ± 101 MBq (11)C-PBR28. For the TRV study, subjects were scanned twice, on average 1.4 weeks apart. Volume of distribution (V T) derived from multilinear analysis (MA1) modeling (t* = 30 min, using arterial input data) was the main outcome measure. RESULTS Mean test V T values (ml cm(-3)) were 3.9 ± 1.4 in the whole brain gray matter (GM), 3.6 ± 1.2 in the whole brain white matter (WM) or normal-appearing white matter (NAWM), and 3.3 ± 0.6 in MS WM lesions; mean retest V T values were 3.7 ± 1.0 in GM, 3.3 ± 0.9 in WM/NAWM, and 3.3 ± 0.7 in MS lesions. Test-retest results showed a mean absolute TRV ranging from 7 to 9 % across GM, WM/NAWM, and MS lesions. High-affinity binders demonstrated 30 % higher V T than medium-affinity binders in GM. Focal (11)C-PBR28 uptake was detected in two enhancing lesions of the active MS patient. CONCLUSION High-resolution (11)C-PBR28 PET can visualize focal areas where microglial activation is known to be present and has good test-retest reproducibility in the human brain. (11)C-PBR28 PET is likely to be valuable for monitoring both MS disease evolution and response to therapeutic strategies that target microglial activation.
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Affiliation(s)
- Eunkyung Park
- PET Center, Department of Diagnostic Radiology, Yale School of Medicine, 801 Howard Avenue, PO Box 208048, New Haven, CT, 06520-8048, USA,
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20
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Slifstein M, van de Giessen E, Van Snellenberg J, Thompson JL, Narendran R, Gil R, Hackett E, Girgis R, Ojeil N, Moore H, D’Souza D, Malison RT, Huang Y, Lim KP, Nabulsi N, Carson RE, Lieberman JA, Abi-Dargham A. Deficits in prefrontal cortical and extrastriatal dopamine release in schizophrenia: a positron emission tomographic functional magnetic resonance imaging study. JAMA Psychiatry 2015; 72:316-24. [PMID: 25651194 PMCID: PMC4768742 DOI: 10.1001/jamapsychiatry.2014.2414] [Citation(s) in RCA: 259] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
IMPORTANCE Multiple lines of evidence suggest a deficit in dopamine release in the prefrontal cortex (PFC) in schizophrenia. Despite the prevalence of the concept of prefrontal cortical hypodopaminergia in schizophrenia, in vivo imaging of dopamine release in the PFC has not been possible until now, when the validity of using the positron emission tomographic D2/3 radiotracer carbon 11-labeled FLB457 in combination with the amphetamine paradigm was clearly established. OBJECTIVES To (1) test amphetamine-induced dopamine release in the dorsolateral PFC (DLPFC) in drug-free or drug-naive patients with schizophrenia (SCZ) and healthy control (HC) individuals matched for age, sex, race/ethnicity, and familial socioeconomic status;(2) test blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging activation during a working memory task in the same participants; and (3) examine the relationship between positron emission tomographic and functional magnetic resonance imaging outcome measures. DESIGN, SETTING AND PARTICIPANTS Positron emission tomographic imaging with carbon 11-labeled FLB457 before and following 0.5 mg/kg of amphetamine by mouth. Blood oxygenation level-dependent functional magnetic resonance imaging during the self-ordered working memory task. Twenty patients with schizophrenia recruited from the inpatient and outpatient research facilities at New York State Psychiatric Institute and 21 healthy control individuals participated, and data were acquired between June 16, 2011, and February 25, 2014. MAIN OUTCOMES AND MEASURE The percentage change in binding potential (∆BPND) in the DLPFC following amphetamine, BOLD activation during the self-ordered working memory task compared with the control task, and the correlation between these 2 outcome measures. RESULTS We observed significant differences in the effect of amphetamine on DLPFC BPND (mean [SD], ∆BPND in HC: -7.5% [11%]; SCZ: +1.8% [11%]; P = .01); a generalized blunting in dopamine release in SCZ involving most extrastriatal regions and the midbrain; and a significant association between ∆BPND and BOLD activation in the DLPFC in the overall sample including patients with SCZ and HC individuals. CONCLUSIONS AND RELEVANCE To our knowledge, these results provide the first in vivo evidence for a deficit in the capacity for dopamine release in the DLPFC in SCZ and suggest a more widespread deficit extending to many cortical and extrastriatal regions including the midbrain. This contrasts with the well-replicated excess in dopamine release in the associative striatum in SCZ and suggests a differential regulation of striatal dopamine release in associative striatum vs extrastriatal regions. Furthermore, dopamine release in the DLPFC relates to working memory-related activation of this region, suggesting that blunted release may affect frontal cortical function.
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Affiliation(s)
- Mark Slifstein
- Columbia University, Department of Psychiatry,New York State Psychiatric Institute
| | | | | | - Judy L. Thompson
- Columbia University, Department of Psychiatry,New York State Psychiatric Institute,The State University of New Jersey, Rutgers
| | - Rajesh Narendran
- University of Pittsburgh Medical Center Department of Psychiatry
| | - Roberto Gil
- Columbia University, Department of Psychiatry,New York State Psychiatric Institute
| | | | - Ragy Girgis
- Columbia University, Department of Psychiatry,New York State Psychiatric Institute
| | | | - Holly Moore
- Columbia University, Department of Psychiatry,New York State Psychiatric Institute
| | - Deepak D’Souza
- Yale University School of Medicine Department of Psychiatry
| | | | - Yiyun Huang
- Yale University School of Medicine PET Center,Yale University School of Medicine Department of Diagnostic Radiology
| | - Keun-poong Lim
- Yale University School of Medicine PET Center,Yale University School of Medicine Department of Diagnostic Radiology
| | - Nabeel Nabulsi
- Yale University School of Medicine PET Center,Yale University School of Medicine Department of Diagnostic Radiology
| | - Richard E. Carson
- Yale University School of Medicine PET Center,Yale University School of Medicine Department of Diagnostic Radiology
| | - Jeffery A. Lieberman
- Columbia University, Department of Psychiatry,New York State Psychiatric Institute
| | - Anissa Abi-Dargham
- Columbia University, Department of Psychiatry,Columbia University, Department of Radiology,New York State Psychiatric Institute
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21
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Pietrzak RH, Naganawa M, Huang Y, Corsi-Travali S, Zheng MQ, Stein MB, Henry S, Lim K, Ropchan J, Lin SF, Carson RE, Neumeister A. Association of in vivo κ-opioid receptor availability and the transdiagnostic dimensional expression of trauma-related psychopathology. JAMA Psychiatry 2014; 71:1262-1271. [PMID: 25229257 DOI: 10.1001/jamapsychiatry.2014.1221] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
IMPORTANCE Exposure to trauma increases the risk for developing threat (ie, fear) symptoms, such as reexperiencing and hyperarousal symptoms, and loss (ie, dysphoria) symptoms, such as emotional numbing and depressive symptoms. While preclinical data have implicated the activated dynorphin/κ-opioid receptor (KOR) system in relation to these symptoms, the role of the KOR system in mediating these phenotypes in humans is unknown. Elucidation of molecular targets implicated in threat and loss symptoms is important because it can help inform the development of novel, mechanism-based treatments for trauma-related psychopathology. OBJECTIVE To use the newly developed [11C]LY2795050 radiotracer and high-resolution positron emission tomography to evaluate the relation between in vivo KOR availability in an amygdala-anterior cingulate cortex-ventral striatal neural circuit and the severity of threat and loss symptoms. We additionally evaluated the role of 24-hour urinary cortisol levels in mediating this association. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional positron emission tomography study under resting conditions was conducted at an academic medical center. Thirty-five individuals representing a broad transdiagnostic and dimensional spectrum of trauma-related psychopathology, ranging from nontrauma-exposed psychiatrically healthy adults to trauma-exposed adults with severe trauma-related psychopathology (ie, posttraumatic stress disorder, major depressive disorder, and/or generalized anxiety disorder). MAIN OUTCOMES AND MEASURES [11C]LY2795050 volume of distribution values in amygdala-anterior cingulate cortex-ventral striatal neural circuit; composite measures of threat (ie, reexperiencing, avoidance, and hyperarousal symptoms) and loss (ie, emotional numbing, major depressive disorder, and generalized anxiety disorder symptoms) symptoms as assessed using the Clinician-Administered PTSD Scale, Hamilton Depression Rating Scale, and Hamilton Rating Scale for Anxiety; and 24-hour urinary cortisol levels. RESULTS [11C]LY2795050 volume of distribution values in an amygdala-anterior cingulate cortex-ventral striatal neural circuit were negatively associated with severity of loss (r = -0.39; 95% CI, -0.08 to -0.66), but not threat (r = -0.03; 95% CI, -0.30 to 0.27), symptoms; this association was most pronounced for dysphoria symptoms (r = -0.45; 95% CI, -0.10 to -0.70). Path analysis revealed that lower [11C]LY2795050 volume of distribution values in this circuit was directly associated with greater severity of loss symptoms and indirectly mediated by 24-hour urinary cortisol levels. CONCLUSIONS AND RELEVANCE Results of this study suggest that KOR availability in an amygdala-anterior cingulate cortex-ventral striatal neural circuit mediates the phenotypic expression of trauma-related loss (ie, dysphoria) symptoms. They further suggest that an activated corticotropin-releasing factor/hypothalamic-pituitary-adrenal axis system, as assessed by 24-hour urinary cortisol levels, may indirectly mediate this association. These results may help inform the development of more targeted, mechanism-based transdiagnostic treatments for loss (ie, dysphoric) symptoms.
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Affiliation(s)
- Robert H Pietrzak
- US Department of Veterans Affairs National Center for Posttraumatic Stress Disorder, Clinical Neurosciences Division, VA Connecticut Healthcare System, West Haven.,Department of Psychiatry, Yale School of Medicine, New Haven, Connecticut
| | - Mika Naganawa
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut
| | - Yiyun Huang
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut
| | - Stefani Corsi-Travali
- Department of Psychiatry, New York University School of Medicine, New York.,Department of Radiology, New York University School of Medicine, New York
| | - Ming-Qiang Zheng
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut
| | - Murray B Stein
- Department of Psychiatry, School of Medicine, University of California, San Diego.,Department of Family and Preventive Medicine, School of Medicine, University of California, San Diego
| | - Shannan Henry
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut
| | - Keunpoong Lim
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut
| | - Jim Ropchan
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut
| | - Shu-Fei Lin
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut
| | - Richard E Carson
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, Connecticut
| | - Alexander Neumeister
- Department of Psychiatry, New York University School of Medicine, New York.,Department of Radiology, New York University School of Medicine, New York.,Steven and Alexandra Cohen Veterans Center, New York, New York
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22
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Lim K, Labaree D, Li S, Huang Y. Preparation of the metabotropic glutamate receptor 5 (mGluR5) PET tracer [(18)F]FPEB for human use: An automated radiosynthesis and a novel one-pot synthesis of its radiolabeling precursor. Appl Radiat Isot 2014; 94:349-354. [PMID: 25305528 DOI: 10.1016/j.apradiso.2014.09.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2014] [Revised: 08/24/2014] [Accepted: 09/09/2014] [Indexed: 12/11/2022]
Abstract
The radiotracer 3-[(18)F]fluoro-5-(2-pyridinylethynyl)benzonitrile, or [(18)F]FPEB, is a promising PET imaging agent for the metabotropic glutamate subtype 5 receptor (mGluR5). In an effort to develop a routine production method of this radiotracer for use in clinical research we adapted its radiosynthesis to an automated chemistry module. In the meanwhile, we also developed a simplified "one-pot" method for the preparation of the nitrobenzonitrile radiolabeling precursor for [(18)F]FPEB and its reference standard to replace the existing multi-step synthetic approach.
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Affiliation(s)
- Keunpoong Lim
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA.
| | - David Labaree
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Songye Li
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Yiyun Huang
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
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23
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Matuskey D, Gallezot JD, Pittman B, Williams W, Wanyiri J, Gaiser E, Lee DE, Hannestad J, Lim K, Zheng MQ, Lin SF, Labaree D, Potenza MN, Carson RE, Malison RT, Ding YS. Dopamine D₃ receptor alterations in cocaine-dependent humans imaged with [¹¹C](+)PHNO. Drug Alcohol Depend 2014; 139:100-5. [PMID: 24717909 PMCID: PMC4071607 DOI: 10.1016/j.drugalcdep.2014.03.013] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2014] [Revised: 02/21/2014] [Accepted: 03/08/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND Evidence from animal models and postmortem human studies points to the importance of the dopamine D₃ receptor (D₃R) in cocaine dependence (CD). The objective of this pilot study was to use the D₃R-preferring radioligand [(11)C](+)PHNO to compare receptor availability in groups with and without CD. METHODS Ten medically healthy, non-treatment seeking CD subjects (mean age 41 ± 8) in early abstinence were compared to 10 healthy control (HC) subjects (mean age 41 ± 6) with no history of cocaine or illicit substance abuse. Binding potential (BPND), a measure of available receptors, was determined with parametric images, computed using the simplified reference tissue model (SRTM2) with the cerebellum as the reference region. RESULTS BPND in CD subjects was higher in D₃R-rich areas including the substantia nigra ((SN) 29%; P=0.03), hypothalamus (28%; P=0.02) and amygdala (35%; P=0.03). No between-group differences were observed in the striatum or pallidum. BPND values in the SN (r=+0.83; P=0.008) and pallidum (r=+0.67; P=0.03) correlated with years of cocaine use. CONCLUSIONS Between-group differences suggest an important role for dopaminergic transmission in the SN, hypothalamus and amygdala in CD. Such findings also highlight the potential relevance of D₃R as a medication development target in CD.
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Affiliation(s)
- David Matuskey
- Department of Psychiatry, Yale University, New Haven, CT, USA; Department of Diagnostic Radiology, Yale University, New Haven, CT, USA.
| | | | - Brian Pittman
- Department of Psychiatry, Yale University, New Haven, CT, USA
| | - Wendol Williams
- Department of Psychiatry, Yale University, New Haven, CT, USA,Department of Diagnostic Radiology, Yale University, New Haven, CT, USA
| | - Jane Wanyiri
- Department of Psychiatry, Yale University, New Haven, CT, USA
| | - Edward Gaiser
- Department of Psychiatry, Yale University, New Haven, CT, USA
| | - Dianne E. Lee
- Department of Diagnostic Radiology, Yale University, New Haven, CT, USA
| | - Jonas Hannestad
- Department of Psychiatry, Yale University, New Haven, CT, USA
| | - Keunpoong Lim
- Department of Diagnostic Radiology, Yale University, New Haven, CT, USA
| | - Minq-Qiang Zheng
- Department of Diagnostic Radiology, Yale University, New Haven, CT, USA
| | - Shu-fei Lin
- Department of Diagnostic Radiology, Yale University, New Haven, CT, USA
| | - David Labaree
- Department of Diagnostic Radiology, Yale University, New Haven, CT, USA
| | - Marc N. Potenza
- Department of Psychiatry, Yale University, New Haven, CT, USA
| | - Richard E. Carson
- Department of Diagnostic Radiology, Yale University, New Haven, CT, USA
| | | | - Yu-Shin Ding
- Department of Radiology and Psychiatry, New York University School of Medicine, New York, NY, USA
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24
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Gallezot JD, Zheng MQ, Lim K, Lin SF, Labaree D, Matuskey D, Huang Y, Ding YS, Carson RE, Malison RT. Parametric Imaging and Test-Retest Variability of ¹¹C-(+)-PHNO Binding to D₂/D₃ Dopamine Receptors in Humans on the High-Resolution Research Tomograph PET Scanner. J Nucl Med 2014; 55:960-6. [PMID: 24732151 DOI: 10.2967/jnumed.113.132928] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 01/21/2014] [Indexed: 11/16/2022] Open
Abstract
UNLABELLED (11)C-(+)-4-propyl-9-hydroxynaphthoxazine ((11)C-(+)-PHNO) is an agonist radioligand for imaging dopamine D2 and D3 receptors in the human brain with PET. In this study we evaluated the reproducibility of (11)C-(+)-PHNO binding parameters using a within-day design and assessed parametric imaging methods. METHODS Repeated studies were performed in 8 subjects, with simultaneous measurement of the arterial input function and plasma free fraction. Two (11)C-(+)-PHNO scans for the same subject were separated by 5.4 ± 0.7 h. After compartment models were evaluated, (11)C-(+)-PHNO volumes of distribution (V(T)) and binding potentials relative to the concentration of tracer in plasma (BP(P)), nondisplaceable tracer in tissue (BP(ND)), and free tracer in tissue (BP(F)) were quantified using the multilinear analysis MA1 method, with the cerebellum as the reference region. Parametric images of BP(ND) were also computed using the simplified reference tissue model (SRTM) and SRTM2. RESULTS The test-retest variability of (11)C-(+)-PHNO BP(ND) was 9% in D2-rich regions (caudate and putamen). Among D3-rich regions, variability was low in the pallidum (6%) but higher in substantia nigra (19%), thalamus (14%), and hypothalamus (21%). No significant mass carry-over effect was observed in D3-rich regions, although a trend in BP(ND) was present in the substantia nigra (-14% ± 15%). Because of the relatively fast kinetics, low-noise BP(ND) parametric images were obtained with both SRTM and SRTM2 without spatial smoothing. CONCLUSION (11)C-(+)-PHNO can be used to compute low-noise parametric images in both D2- and D3-rich regions in humans.
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Affiliation(s)
- Jean-Dominique Gallezot
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - Ming-Qiang Zheng
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - Keunpoong Lim
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - Shu-fei Lin
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - David Labaree
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - David Matuskey
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut; and
| | - Yiyun Huang
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - Yu-Shin Ding
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut Department of Radiology and Psychiatry, New York University School of Medicine, New York, New York
| | - Richard E Carson
- PET Center, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut
| | - Robert T Malison
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut; and
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25
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Gallezot JD, Kloczynski T, Weinzimmer D, Labaree D, Zheng MQ, Lim K, Rabiner EA, Ridler K, Pittman B, Huang Y, Carson RE, Morris ED, Cosgrove KP. Imaging nicotine- and amphetamine-induced dopamine release in rhesus monkeys with [(11)C]PHNO vs [(11)C]raclopride PET. Neuropsychopharmacology 2014; 39:866-74. [PMID: 24220025 PMCID: PMC3924521 DOI: 10.1038/npp.2013.286] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/12/2013] [Revised: 07/15/2013] [Accepted: 07/16/2013] [Indexed: 11/09/2022]
Abstract
The radiotracer [(11)C]PHNO may have advantages over other dopamine (DA) D2/D3 receptor ligands because, as an agonist, it measures high-affinity, functionally active D2/D3 receptors, whereas the traditionally used radiotracer [(11)C]raclopride measures both high- and low-affinity receptors. Our aim was to take advantage of the strength of [(11)C]PHNO for measuring the small DA signal induced by nicotine, which has been difficult to measure in preclinical and clinical neuroimaging studies. Nicotine- and amphetamine-induced DA release in non-human primates was measured with [(11)C]PHNO and [(11)C]raclopride positron emission tomography (PET) imaging. Seven adult rhesus monkeys were imaged on a FOCUS 220 PET scanner after injection of a bolus of [(11)C]PHNO or [(11)C]raclopride in three conditions: baseline; preinjection of nicotine (0.1 mg/kg bolus+0.08 mg/kg infusion over 30 min); preinjection of amphetamine (0.4 mg/kg, 5 min before radiotracer injection). DA release was measured as change in binding potential (BPND). Nicotine significantly decreased BPND in the caudate (7 ± 8%), the nucleus accumbens (10 ± 7%), and in the globus pallidus (13 ± 15%) measured with [(11)C]PHNO, but did not significantly decrease BPND in the putamen or the substantia nigra or in any region when measured with [(11)C]raclopride. Amphetamine significantly reduced BPND in all regions with both radiotracers. In the striatum, larger amphetamine-induced changes were detected with [(11)C]PHNO compared with [(11)C]raclopride (52-64% vs 33-35%, respectively). We confirmed that [(11)C]PHNO is more sensitive than [(11)C]raclopride to nicotine- and amphetamine-induced DA release. [(11)C]PHNO PET may be more sensitive to measuring tobacco smoking-induced DA release in human tobacco smokers.
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Affiliation(s)
- Jean-Dominique Gallezot
- Department of Diagnostic Radiology, Yale PET Center, Yale University School of Medicine, New Haven, CT, USA
| | - Tracy Kloczynski
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - David Weinzimmer
- Department of Diagnostic Radiology, Yale PET Center, Yale University School of Medicine, New Haven, CT, USA
| | - David Labaree
- Department of Diagnostic Radiology, Yale PET Center, Yale University School of Medicine, New Haven, CT, USA
| | - Ming-Qiang Zheng
- Department of Diagnostic Radiology, Yale PET Center, Yale University School of Medicine, New Haven, CT, USA
| | - Keunpoong Lim
- Department of Diagnostic Radiology, Yale PET Center, Yale University School of Medicine, New Haven, CT, USA
| | | | | | - Brian Pittman
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Yiyun Huang
- Department of Diagnostic Radiology, Yale PET Center, Yale University School of Medicine, New Haven, CT, USA
| | - Richard E Carson
- Department of Diagnostic Radiology, Yale PET Center, Yale University School of Medicine, New Haven, CT, USA,Department of Biomedical Engineering, Yale University School of Medicine, New Haven, CT, USA
| | - Evan D Morris
- Department of Diagnostic Radiology, Yale PET Center, Yale University School of Medicine, New Haven, CT, USA,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA,Department of Biomedical Engineering, Yale University School of Medicine, New Haven, CT, USA
| | - Kelly P Cosgrove
- Department of Diagnostic Radiology, Yale PET Center, Yale University School of Medicine, New Haven, CT, USA,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA,Department of Psychiatry, Yale University School of Medicine, 2 Church Street South, Suite 511, New Haven, CT 06519, USA, Tel: +1 203 737 6969, E-mail:
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26
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Hannestad J, DellaGioia N, Gallezot JD, Lim K, Nabulsi N, Esterlis I, Pittman B, Lee JY, O’Connor KC, Pelletier D, Carson RE. The neuroinflammation marker translocator protein is not elevated in individuals with mild-to-moderate depression: a [¹¹C]PBR28 PET study. Brain Behav Immun 2013; 33:131-8. [PMID: 23850810 PMCID: PMC3899398 DOI: 10.1016/j.bbi.2013.06.010] [Citation(s) in RCA: 160] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2013] [Revised: 06/26/2013] [Accepted: 06/30/2013] [Indexed: 11/29/2022] Open
Abstract
Depression is associated with systemic inflammation. In animals, systemic inflammation can induce neuroinflammation and activation of microglia; however, postmortem studies have not convincingly shown that there is neuroinflammation in depression. The purpose of this study was to use positron emission tomography (PET) with [¹¹C]PBR28, which binds to the neuroinflammation marker translocator protein 18 kDa (TSPO), to compare the level of TSPO between individuals with depression and control subjects. Ten individuals who were in an acute episode of major depression and 10 control subjects matched for TSPO genotype and other characteristics had a PET scan with arterial input function to quantify levels of TSPO in brain regions of interest (ROIs). Total volume of distribution (VT) of [¹¹C]PBR28 was used as a measure of total ligand binding. The primary outcome was the difference in VT between the two groups; this was assessed using a linear mixed model with group as a between-subject factor and region as a within-subject factor. There was no statistically significant difference in [¹¹C]PBR28 binding (VT) between the two groups. In fact, 7 of 10 individuals with depression had lower [¹¹C]PBR28 binding in all ROIs compared to their respective genotype-matched control subjects. Future studies are needed to determine whether individuals with mild-to-moderate depression have lower TSPO levels and to assess whether individuals with severe depression and/or with elevated levels of systemic inflammation might have higher TSPO levels than control subjects.
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Affiliation(s)
- Jonas Hannestad
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA.
| | - Nicole DellaGioia
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | | | - Keunpoong Lim
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, CT, USA
| | - Nabeel Nabulsi
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, CT, USA
| | - Irina Esterlis
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Brian Pittman
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA
| | - Jae-Yun Lee
- Department of Neurology, Program in Human and Translational Immunology, Yale School of Medicine, New Haven, CT, USA
| | - Kevin C. O’Connor
- Department of Neurology, Program in Human and Translational Immunology, Yale School of Medicine, New Haven, CT, USA
| | - Daniel Pelletier
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, CT, USA,Department of Neurology, Program in Human and Translational Immunology, Yale School of Medicine, New Haven, CT, USA
| | - Richard E. Carson
- Department of Diagnostic Radiology, Yale School of Medicine, New Haven, CT, USA
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27
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Lee DE, Gallezot JD, Zheng MQ, Lim K, Ding YS, Huang Y, Carson RE, Morris ED, Cosgrove KP. Test-retest reproducibility of [11C]-(+)-propyl-hexahydro-naphtho-oxazin positron emission tomography using the bolus plus constant infusion paradigm. Mol Imaging 2013; 12:77-82. [PMID: 23415395 PMCID: PMC3699696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023] Open
Abstract
We examined the reproducibility of using the constant infusion paradigm for equilibrium measurement of D2/3 receptors using [11C]-(+)-propyl-hexahydro-naphtho-oxazin (PHNO) positron emission tomography (PET). Six subjects were scanned with a bolus plus constant infusion (Kbol = 80 minutes) of [11C]-(+)-PHNO. Binding potential (BPND) was computed using the equilibrium approach and compared to a simplified reference tissue model (SRTM). The rate of change in the concentration-activity curve from 60 to 90 minutes was -5 ± 13%/h in the caudate, putamen, substantia nigra, thalamus, and cerebellum but was 15 ± 15%/h in the ventral striatum and pallidum. Test-retest variability was lower in striatal compared to extrastriatal regions (4 ± 8% vs -8 ± 22%, respectively) using the equilibrium approach, with comparable results with SRTM. The equilibrium ratio and SRTM yielded reliable BPND estimates (intraclass correlation coefficient = 0.88 and 0.82, respectively). These studies support the reproducibility of the bolus plus constant infusion paradigm with [11C]-(+)-PHNO PET.
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Affiliation(s)
- Dianne E. Lee
- Department of Diagnostic Radiology, Yale PET Center, Yale School of Medicine, New Haven, Connecticut
| | - Jean-Dominique Gallezot
- Department of Diagnostic Radiology, Yale PET Center, Yale School of Medicine, New Haven, Connecticut
| | - Ming-Qiang Zheng
- Department of Diagnostic Radiology, Yale PET Center, Yale School of Medicine, New Haven, Connecticut
| | - Keunpoong Lim
- Department of Diagnostic Radiology, Yale PET Center, Yale School of Medicine, New Haven, Connecticut
| | - Yu-Shin Ding
- Department of Diagnostic Radiology, Yale PET Center, Yale School of Medicine, New Haven, Connecticut
| | - Yiyun Huang
- Department of Diagnostic Radiology, Yale PET Center, Yale School of Medicine, New Haven, Connecticut
| | - Richard E. Carson
- Department of Diagnostic Radiology, Yale PET Center, Yale School of Medicine, New Haven, Connecticut
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut
| | - Evan D. Morris
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
- Department of Diagnostic Radiology, Yale PET Center, Yale School of Medicine, New Haven, Connecticut
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut
| | - Kelly P. Cosgrove
- Department of Psychiatry, Yale University School of Medicine, New Haven, Connecticut
- Department of Diagnostic Radiology, Yale PET Center, Yale School of Medicine, New Haven, Connecticut
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28
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Hanham SM, Fernández-Domínguez AI, Teng JH, Ang SS, Lim KP, Yoon SF, Ngo CY, Klein N, Pendry JB, Maier SA. Broadband terahertz plasmonic response of touching InSb disks. Adv Mater 2012; 24:OP226-OP230. [PMID: 22807039 DOI: 10.1002/adma.201202003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Revised: 06/18/2012] [Indexed: 06/01/2023]
Affiliation(s)
- S M Hanham
- Dept. of Physics, Imperial College London, South Kensington, London SW7 2AZ, UK.
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29
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Hannestad J, Gallezot JD, Schafbauer T, Lim K, Kloczynski T, Morris ED, Carson RE, Ding YS, Cosgrove KP. Endotoxin-induced systemic inflammation activates microglia: [¹¹C]PBR28 positron emission tomography in nonhuman primates. Neuroimage 2012; 63:232-9. [PMID: 22776451 DOI: 10.1016/j.neuroimage.2012.06.055] [Citation(s) in RCA: 166] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Revised: 05/31/2012] [Accepted: 06/26/2012] [Indexed: 12/21/2022] Open
Abstract
UNLABELLED Microglia play an essential role in many brain diseases. Microglia are activated by local tissue damage or inflammation, but systemic inflammation can also activate microglia. An important clinical question is whether the effects of systemic inflammation on microglia mediate the deleterious effects of systemic inflammation in diseases such as Alzheimer's dementia, multiple sclerosis, and stroke. Positron Emission Tomography (PET) imaging with ligands that bind to Translocator Protein (TSPO) can be used to detect activated microglia. The aim of this study was to evaluate whether the effect of systemic inflammation on microglia could be measured with PET imaging in nonhuman primates, using the TSPO ligand [(11)C]PBR28. METHODS Six female baboons (Papio anubis) were scanned before and at 1h and/or 4h and/or 22 h after intravenous administration of E. coli lipopolysaccharide (LPS; 0.1mg/kg), which induces systemic inflammation. Regional time-activity data from regions of interest (ROIs) were fitted to the two-tissue compartmental model, using the metabolite-corrected arterial plasma curve as input function. Total volume of distribution (V(T)) of [(11)C]PBR28 was used as a measure of total ligand binding. The primary outcome was change in V(T) from baseline. Serum levels of tumor necrosis factor alpha (TNFα), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and interleukin-8 (IL-8) were used to assess correlations between systemic inflammation and microglial activation. In one baboon, immunohistochemistry was used to identify cells expressing TSPO. RESULTS LPS administration increased [(11)C]PBR28 binding (F(3,6)=5.1, p=.043) with a 29 ± 16% increase at 1h (n=4) and a 62 ± 34% increase at 4h (n=3) post-LPS. There was a positive correlation between serum IL-1β and IL-6 levels and the increase in [(11)C]PBR28 binding. TSPO immunoreactivity occurred almost exclusively in microglia and rarely in astrocytes. CONCLUSION In the nonhuman-primate brain, LPS-induced systemic inflammation produces a robust increase in the level of TSPO that is readily detected with [(11)C]PBR28 PET. The effect of LPS on [(11)C]PBR28 binding is likely mediated by inflammatory cytokines. Activation of microglia may be a mechanism through which systemic inflammatory processes influence the course of diseases such as Alzheimer's, multiple sclerosis, and possibly depression.
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Affiliation(s)
- Jonas Hannestad
- Department of Psychiatry, Yale School of Medicine, New Haven, CT, USA.
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Wang Y, Lim K, Normandin M, Zhao X, Cline GW, Ding YS. Synthesis and evaluation of [18F]exendin (9-39) as a potential biomarker to measure pancreatic β-cell mass. Nucl Med Biol 2011; 39:167-76. [PMID: 22033026 DOI: 10.1016/j.nucmedbio.2011.07.011] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2010] [Revised: 06/24/2011] [Accepted: 07/15/2011] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Glucagon-like peptide 1 (GLP-1) is released in response to food intake and plays an important role in maintaining blood glucose homeostasis. Exendin (9-39), a potent glucagon-like peptide 1 receptor antagonist, has been labeled with In-111 for SPECT imaging. We report here the first radiosynthesis of [(18)F]exendin (9-39) ([(18)F]Ex(9-39)) and an evaluation of its potential as a biomarker for in vivo positron emission tomography (PET) imaging of pancreatic β-cell mass (BCM) in rats. METHODS F-18 label was introduced by conjugation of [(18)F]4-fluorobenzaldehyde with an Ex(9-39) derivative containing a 6-hydrazinonicotinyl group on the ε-amine of Lys27. Positron emission tomography imaging was carried out in Sprague-Dawley rats (five control and five streptozotocin-induced diabetic) and BioBreeding diabetes-prone rats (three at 7 weeks and three at 12 weeks) using the high-resolution research tomograph (HRRT) after 0.187 ± 0.084 mCi [(18)F]Ex(9-39) administration. Time-activity curves were obtained from pancreas, liver and kidney. Pancreases were assayed for insulin content after the imaging study. RESULTS Site-specifically labeled [(18)F]Ex(9-39) was purified on a G15 open column with radiochemical and chemical purities >98%. Positron emission tomography imaging showed pancreatic standardized uptake value (SUV) peaked at 10 min and plateaued by 50 min to the end of scan (240 min). No correlations of pancreatic SUV with postmortem measures of insulin content were seen. CONCLUSIONS [(18)F]Ex(9-39) was successfully prepared and used for PET imaging for the first time to measure pancreatic BCM. The results suggest that derivatization of the Lys27 residue might reduce binding affinity, as evidenced by the absence of specific binding. Exendin analogues radiolabeled at other sites may elucidate the active site required for binding.
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Affiliation(s)
- Yi Wang
- Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, CT 06520, USA
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Cosgrove K, Gallezot JD, Weinzimmer D, Fowles K, Labaree D, Zheng MQ, Lim K, Carson R, Morris E. Imaging drug-induced dopamine release in rhesus monkeys with [11C]PHNO versus [11C]raclopride PET. Neuroimage 2010. [DOI: 10.1016/j.neuroimage.2010.04.063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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32
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Sullivan JM, Lim K, Labree D, Lin SF, McCarthy TJ, Seibyl J, Tamagnan G, Huang Y, Carson RE, Morris ED, Ding YS. Kinetic modeling of the mGluR5 tracer [18F]F-FPEB in humans. Neuroimage 2010. [DOI: 10.1016/j.neuroimage.2010.04.138] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Abstract
Synthesis of tissue adhesives had been carried out in various laboratories in the past decades but the development is currently stalled. One of the key reasons, it is believed, is that researchers have not fully understood and resolved the role of the functional groups that are responsible for good adhesion to biological tissues. Further progress in synthesis is significantly hindered without this fundamental understanding. With this aim in mind, atomic force microscopy (AFM) has been exploited in this work to study the interactions between functional groups that are common to biological tissues. In this work, the AFM tip and substrates were functionalized and used to measure the non-specific interaction among these common functional groups. The ultimate aim of the study is to calculate the interaction force between a single pair of functional groups. A novel calculation method based on the AFM data and probe geometry is presented. The results provide insights into the strength of the bond between different functional groups and the could serve as a guide in selecting the appropriate functional groups in tissue adhesive synthesis. This method could be further applied to studies involving interfaces of biomedical devices where intermolecular interactions are of concern.
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Affiliation(s)
- K P Lim
- School of Materials Science and Engineering, Nanyang Technological University, Blk N4.1, Nanyang Avenue, Singapore 639798, Singapore
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Dai Q, Xu D, Lim K, Harvey RG. Efficient Syntheses ofC8-Aryl Adducts of Adenine and Guanine Formed by Reaction of Radical Cation Metabolites of Carcinogenic Polycyclic Aromatic Hydrocarbons with DNA. J Org Chem 2007; 72:4856-63. [PMID: 17530898 DOI: 10.1021/jo070518m] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The synthesis of the C(8)-aryl adducts of adenine and guanine formed by reaction of the radical cation metabolites of carcinogenic polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene (BP) and dibenzo[def,p]chrysene (DBC), with DNA is reported. The synthetic approach involves in the key step direct reaction of a PAH aldehyde with a di- or triamine precursor of a purine. The method is operationally simple, affords good yields of adducts, and is broad in its scope. The C(8)-aryl adducts of adenine and guanine derived from BP (6-BP-8-Ade and 6-BP-8-Gua) and DBC (10-DBC-8-Ade and 10-DBC-8-Gua) were synthesized in good yields by this method. Analogous C(8)-aryl adenine and guanine derivatives of other PAHs (anthracene, benz[a]anthracene, and chrysene) were also readily prepared via this approach. This method of synthesis is superior to the only method that is currently available. It entails direct reaction of short-lived PAH radical cations (generated electrochemically or chemically) with 2'-deoxyribonucleosides or the corresponding purine bases. It provides the adducts in low yields accompanied by complex mixtures of secondary products. An alternative synthesis that involves Pd-catalyzed Suzuki-Miyaura coupling of arylboronic acids with 8-bromopurine nucleosides was also investigated. Although the C(8)-purine adducts of PAHs, such as naphthalene, phenanthrene, pyrene, and chrysene, could be prepared by this method, analogous adducts of carcinogenic PAHs and other structurally related PAHs, e.g., anthracene, benz[a]anthracene, benzo[a]pyrene, and dibenzo[def,p]chrysene, could not be obtained. This difference was shown to be a consequence of the facility of competing hydrolytic deboronation of the corresponding arylboronic acids.
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Affiliation(s)
- Qing Dai
- The Ben May Department for Cancer Research, The University of Chicago, Chicago, Illinois 60637, USA
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35
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Harvey RG, Dai Q, Ran C, Lim K, Blair I, Penning TM. SYNTHESES OF ADDUCTS OF ACTIVE METABOLITES OF CARCINOGENIC POLYCYCLIC AROMATIC HYDROCARBONS WITH 2′-DEOXYRIBONUCLEOSIDES. Polycycl Aromat Compd 2005. [DOI: 10.1080/10406630500447019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Abstract
A convenient new synthesis of the ubiquitous environmental carcinogen benzo[a]pyrene (BaP) is described. In the key step, the method entails Suzuki coupling of naphthalene 2-boronic acid with 2-bromobenzene-1,3-dialdehyde and requires only three steps. It is considerably shorter and simpler than the older methods and provides BaP in higher overall yield.
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Affiliation(s)
- Ronald G Harvey
- The Ben May Institute for Cancer Research, The University of Chicago, Chicago, Illinois 60637, USA.
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37
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Banerjee GK, Lim KP, Cohen NP. Penile metastasis: an unusual presentation of metastatic colonic cancer. J R Coll Surg Edinb 2002; 47:763-4. [PMID: 12510969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
We report here an interesting presentation of a primary colonic carcinoma in a urological setting. A previously unknown case of colonic carcinoma presented with a lesion in the glans penis which was later diagnosed as a secondary deposit from colonic cancer. Penile involvement has been implicated as a metastatic site in several tumours. Although uncommon, this presentation is not unknown. A literature review of this unusual presentation has been performed and is summarised in the article
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Affiliation(s)
- G K Banerjee
- Ward 44, Aberdeen Royal Infirmary, Foresterhill, Aberdeen, AB25 2ZN, UK
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38
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Lim KP, Xu HY, Liu DX. Physical interaction between the membrane (M) and envelope (E) proteins of the coronavirus avian infectious bronchitis virus (IBV). Adv Exp Med Biol 2002; 494:595-602. [PMID: 11774531 DOI: 10.1007/978-1-4615-1325-4_88] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Affiliation(s)
- K P Lim
- Institute of Molecular Agrobiology, National University of Singapore, 1 Research Link, Singapore 117604
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39
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Xu HY, Lim KP, Shen S, Liu DX. Further identification and characterization of novel intermediate and mature cleavage products released from the ORF 1b region of the avian coronavirus infectious bronchitis virus 1a/1b polyprotein. Virology 2001; 288:212-22. [PMID: 11601893 PMCID: PMC7134593 DOI: 10.1006/viro.2001.1098] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The coronavirus 3C-like proteinase is one of the viral proteinases responsible for processing of the 1a and 1a/1b polyproteins to multiple mature products. In cells infected with avian coronavirus infectious bronchitis virus (IBV), three proteins of 100, 39, and 35 kDa, respectively, were previously identified as mature cleavage products released from the 1b region of the 1a/1b polyprotein by the 3C-like proteinase. In this report, we show the identification of two more cleavage products of 68 and 58 kDa released from the same region of the polyprotein. In addition, two stable intermediate cleavage products with molecular masses of 160 and 132 kDa, respectively, were identified in IBV-infected cells. The 160-kDa protein was shown to be an intermediate cleavage product covering the 100- and 68-kDa proteins, and the 132-kDa protein to be an intermediate cleavage product covering the 58-, 39-, and 35-kDa proteins. Immunofluorescent staining of IBV-infected cells and cells expressing individual cleavage products showed that the 100-, 68-, and 58-kDa proteins were associated with the membranes of the endoplasmic reticulum, and the 39- and 35-kDa proteins displayed diffuse distribution patterns.
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Affiliation(s)
- H Y Xu
- Institute of Molecular Agrobiology, 1 Research Link, The National University of Singapore, Singapore 117604
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40
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Lim KP, Liu DX. The missing link in coronavirus assembly. Retention of the avian coronavirus infectious bronchitis virus envelope protein in the pre-Golgi compartments and physical interaction between the envelope and membrane proteins. J Biol Chem 2001; 276:17515-23. [PMID: 11278557 PMCID: PMC7982318 DOI: 10.1074/jbc.m009731200] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2000] [Revised: 01/29/2001] [Indexed: 11/18/2022] Open
Abstract
One missing link in the coronavirus assembly is the physical interaction between two crucial structural proteins, the membrane (M) and envelope (E) proteins. In this study, we demonstrate that the coronavirus infectious bronchitis virus E can physically interact, via a putative peripheral domain, with M. Deletion of this domain resulted in a drastic reduction in the incorporation of M into virus-like particles. Immunofluorescent staining of cells coexpressing M and E supports that E interacts with M and relocates M to the same subcellular compartments that E resides in. E was retained in the pre-Golgi membranes, prior to being translocated to the Golgi apparatus and the secretory vesicles; M was observed to exhibit similar localization and translocation profiles as E when coexpressed with E. Deletion studies identified the C-terminal 6-residue RDKLYS as the endoplasmic reticulum retention signal of E, and site-directed mutagenesis of the -4 lysine residue to glutamine resulted in the accumulation of E in the Golgi apparatus. The third domain of E that plays a crucial role in virus budding is a putative transmembrane domain present at the N-terminal region, because deletion of the domain resulted in a free distribution of the mutant protein and in dysfunctional viral assembly.
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Affiliation(s)
- K P Lim
- Institute of Molecular Agrobiology, The National University of Singapore, 1 Research Link, Singapore 117604
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41
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Lim KP, Chong MN, Das A. Low-bit-rate video coding using dense motion field and uncovered background prediction. IEEE Trans Image Process 2001; 10:164-166. [PMID: 18249607 DOI: 10.1109/83.892453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
It is well known that accurate dense motion field can improve the video coding efficiency. This paper presents a novel Markov random field (MRF) model that estimates both the dense motion and uncovered background fields in image sequences, and the application of these estimates in H.263-based video coding framework.
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Affiliation(s)
- K P Lim
- School of Applied Science, Nanyang Technological University, Singapore 639798
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42
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Lim KP, Ng LF, Liu DX. Identification of a novel cleavage activity of the first papain-like proteinase domain encoded by open reading frame 1a of the coronavirus Avian infectious bronchitis virus and characterization of the cleavage products. J Virol 2000; 74:1674-85. [PMID: 10644337 PMCID: PMC111642 DOI: 10.1128/jvi.74.4.1674-1685.2000] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.3] [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: 07/26/1999] [Accepted: 11/06/1999] [Indexed: 11/20/2022] Open
Abstract
The coronavirus Avian infectious bronchitis virus (IBV) employs polyprotein processing as a strategy to express its gene products. Previously we identified the first cleavage event as proteolysis at the Gly(673)-Gly(674) dipeptide bond mediated by the first papain-like proteinase domain (PLPD-1) to release an 87-kDa mature protein. In this report, we demonstrate a novel cleavage activity of PLPD-1. Expression, deletion, and mutagenesis studies showed that the product encoded between nucleotides 2548 and 8865 was further cleaved by PLPD-1 at the Gly(2265)-Gly(2266) dipeptide bond to release an N-terminal 195-kDa and a C-terminal 41-kDa cleavage product. Characterization of the cleavage activity revealed that the proteinase is active on this scissile bond when expressed in vitro in rabbit reticulocyte lysates and can act on the same substrate in trans when expressed in intact cells. Both the N- and C-terminal cleavage products were detected in virus-infected cells and were found to be physically associated. Glycosidase digestion and site-directed mutagenesis studies of the 41-kDa protein demonstrated that it is modified by N-linked glycosylation at the Asn(2313) residue encoded by nucleotides 7465 to 7467. By using a region-specific antiserum raised against the IBV sequence encoded by nucleotides 8865 to 9786, we also demonstrated that a 33-kDa protein, representing the 3C-like proteinase (3CLP), was specifically immunoprecipitated from the virus-infected cells. Site-directed mutagenesis and expression studies showed that a previously predicted cleavage site (Q(2583)-G(2584)) located within the 41-kDa protein-encoding region was not utilized by 3CLP, supporting the conclusion that the 41-kDa protein is a mature viral product.
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Affiliation(s)
- K P Lim
- Institute of Molecular Agrobiology, National University of Singapore, Singapore 117604, Singapore
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Tan WC, Lim KP, Ng TP, Chao TC, Ong YY, Chee YC. Long-term outcome and disease control in near-fatal asthma. Ann Acad Med Singap 1999; 28:384-8. [PMID: 10575523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Patients who have survived an episode of intubation and mechanical ventilation for acute respiratory failure due to a severe and unresponsive asthmatic attack are considered to have experienced a near-fatal asthma (NFA) attack. Such patients are at a higher risk of similar severe attacks and hence of death in the future. The aims of the study were to: (i) evaluate the outcome; (ii) identify any persistent deficiencies in asthma management, and (iii) assess self-management knowledge in survivors of NFA. Ninety-three consecutive patients who had been treated for NFA in the Intensive Care Unit of an urban teaching hospital in Singapore from 1992 to 1997 were studied. All hospital records were reviewed retrospectively. Survivors were then invited to attend a questionnaire interview and to have lung function tests performed. Of the original cohort (OC) of 93 patients with NFA (mean age 55.2 years), 18 (19% OC) patients (mean age 64 years) had died while in hospital and 75 (81% OC) patients survived the initial episode of NFA and were discharged home (DH). The long-term outcome of this DH group was: 13 patients had died (17% DH) and 62 (83% DH) survived. Of these survivors, 35 were interviewed while 27 declined or were not contactable. This interview yielded the following information: (i) Hospitalisation in the past year: 66% had no hospital admission; of the 31.4% who had 2 or more admissions, most had a further NFA attack. (ii) Health care: The majority of patients (71.4%) were monitored by a single doctor. (iii) Patient knowledge of disease management was deemed good to fair for trigger avoidance (77%), for appropriate drug usage (97%). (iv) Satisfactory inhaler skill (80%). NFA is associated with a high intrahospital and long-term mortality. Although most survivors of NFA appeared to have satisfactory care and a fair understanding of medication usage, a significant minority continue to pose much morbidity and risk for death.
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Affiliation(s)
- W C Tan
- Department of Medicine, National University of Singapore
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44
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Liu DX, Xu HY, Lim KP. Regulation of mRNA 1 expression by the 5'-untranslated region (5'-UTR) of the coronavirus infectious bronchitis virus (IBV). Adv Exp Med Biol 1998; 440:303-11. [PMID: 9782297 DOI: 10.1007/978-1-4615-5331-1_40] [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] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
In this report, we show that expression of the coronavirus IBV mRNA1 is regulated by its 5'-UTR. Evidence presented demonstrates that the IBV sequence from nucleotide 1 to 1904 directs very inefficient synthesis of a product of approximately 43 kDa. Deletion of either the first 362 bp or the whole part of the 5'-UTR, however, dramatically increased the expression of the 43 kDa protein species. The mechanisms involved were investigated by two different approaches. Firstly, translation of the same construct in the presence of [3H]-leucine ruled out the possibility that initiation of small reading frames from non-AUG codons located in the 5'-UTR may compete with the authentic AUG initiation codon, and therefore inhibit the expression of ORF 1a. Secondly, expression and deletion analyses of a dicistronic construct showed that translation of the 43 kDa protein was initiated by ribosome internal entry mechanism. These studies suggest that a 'weak' ribosome internal entry signal is located in the 5'-UTR and is involved in the regulation of mRNA1 expression.
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Affiliation(s)
- D X Liu
- Institute of Molecular Agrobiology, National University of Singapore
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Lim KP, Liu DX. Characterisation of a papain-like proteinase domain encoded by ORF1a of the coronavirus IBV and determination of the C-terminal cleavage site of an 87 kDa protein. Adv Exp Med Biol 1998; 440:173-84. [PMID: 9782279 DOI: 10.1007/978-1-4615-5331-1_22] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Our previous studies have shown that two overlapping papain-like proteinase domains (PLPDs) encoded by the IBV sequence from nucleotides 4155 to 5550 is responsible for cleavage of the ORF 1a polyprotein to an 87 kDa protein. In this study, we demonstrate that only the more 5' one of the two domains, PLPD-1 encoded between nucleotides 4155 and 5031, is required for processing to the 87 kDa protein. Site-directed mutagenesis studies have shown that the Cys1274 and His1435 residues are essential for the PLPD-1 activity, suggesting that they may be the components of the catalytic centre of this proteinase. Coexpression and immunoprecipitation studies have further revealed that PLPD can interact with the 87 kDa protein. Meanwhile, data obtained from the construction and expression of a series of deletion mutants have indicated that the 87 kDa protein is encoded by the 5'-most 2600 bp part of ORF1a. further deletion and mutagenesis studies are underway to determine precisely the C-terminal cleavage site of the 87 kDa protein.
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Affiliation(s)
- K P Lim
- Institute of Molecular Agrobiology, Singapore
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46
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Lim KP, Liu DX. Characterization of the two overlapping papain-like proteinase domains encoded in gene 1 of the coronavirus infectious bronchitis virus and determination of the C-terminal cleavage site of an 87-kDa protein. Virology 1998; 245:303-12. [PMID: 9636369 PMCID: PMC7131824 DOI: 10.1006/viro.1998.9164] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
In a previous report, we showed that proteolytic processing of an 87-kDa mature viral protein from the coronavirus infectious bronchitis virus (IBV) 1a and 1a/1b polyproteins was mediated by two putative overlapping papain-like proteinase domains (PLPDs) encoded within the region from nucleotides 4243 to 5553 of ORF 1a (Liu et al., 1995). In this study, we demonstrate that only the first domain, PLPD-1, is responsible for this cleavage, as deletion of the second domain did not affect the formation of the 87-kDa protein. Site-directed mutagenesis studies further showed that a previously predicted nucleophilic cysteine residue (Cys1274) and a histidine residue (His1437) were essential for the proteinase activity, indicating that they may be important components of the catalytic center of the proteinase. Meanwhile, expression of a series of deletion mutants revealed that the 87-kDa protein was encoded by the 5'-most 2.6 kb of ORF 1a. Deletion and amino acid substitution mutation studies demonstrated that the Gly673-Gly674 dipeptide bond was most likely the cleavage site responsible for releasing the C-terminus of the 87-kDa protein from the 1a and 1a/1b polyproteins.
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Affiliation(s)
- K P Lim
- Institute of Molecular Agrobiology, National University of Singapore, Singapore
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Abstract
The hydrolysis of o-nitrophenyl galactopyranoside and lactose by beta-D-galactosidase from Kluyveromyces lactis was enhanced by the addition of Mg2+ and Mn2+, but the rates of activation by each metal on both substrates were not the same. The Co2+, Zn2+, and Ni2+ activated the o-nitrophenyl galactopyranoside-hydrolyzing activity of the enzyme, but these same metals inhibited the lactose-hydrolyzing activity. The addition of Mg2+ and EDTA to the assay buffer increased the hydrolysis of o-nitrophenyl galactopyranoside and lactose at different rates. The responses of o-nitrophenyl galactopyranoside and lactose to the enzyme activity were different as a function of pH. The hydrolyzing activity toward both substrates also was influenced by the concentration of the phosphate in the assay buffer. However, the profile of the enzyme activity toward each substrate was different as a function of concentration. Because the assay of beta-galactosidase using o-nitrophenyl galactopyranoside is fast and convenient, the estimation of lactose-hydrolyzing activity of the enzyme has frequently been made based on the assay of o-nitrophenyl galactopyranoside hydrolysis. As shown in this study, a slight change in the conditions of the assay system and the enzyme application may cause changes in the ability of the enzyme to hydrolyze both lactose and o-nitrophenyl galactopyranoside. The change in o-nitrophenyl galactopyranoside-hydrolyzing activity is not always consistent with that of the lactose-hydrolyzing activity under the given condition, which may cause an inaccurate estimation of the enzyme activity in the enzyme preparation as well as in actual applications of the enzyme.
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Affiliation(s)
- S H Kim
- Culture Systems, Inc., Mishawaka, IN 46545, USA
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Chow VT, Lim KP. Amplification and sequencing of varicella-zoster virus (VZV) gene 4: point mutation in a VZV strain causing chickenpox during pregnancy. Acta Virol 1997; 41:277-83. [PMID: 9607081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The varicella-zoster virus (VZV) causes chickenpox (varicella) as the primary disease and shingles (zoster) as a recurrent manifestation of infection, both being generally benign and self-limiting. While these infections may be severe in adults and even life-threatening in immunosuppressed individuals, they may be amenable to effective antiviral drugs or varicella-zoster immune globulin, provided the treatment is administered early. The prompt diagnosis of VZV infections may be accelerated by rapid, sensitive and specific molecular techniques such as amplification by polymerase chain reaction (PCR) compared with slower and more cumbersome tissue culture and serological procedures. Based on the VZV gene 4 which encodes a transcriptional activator, primers were designed for use in PCR to amplify a target fragment of 381 bp. Distinct diagnostic bands were observed by agarose gel electrophoresis of PCR products of VZV strains isolated from 11 varicella and 7 zoster patients in Singapore, as well as of the Japanese vaccine Oka strain. The detection sensitivity of this PCR assay was determined to be 1 pg of purified VZV DNA equivalent to about 7,000 viral DNA copies. No target bands were amplified from negative control templates from five related human herpes-viruses and from human DNA. The specificity of the PCR products was ensured by direct cycle DNA sequencing, which revealed complete identity of the 18 VZV isolates with the published European Dumas strain. The strong sequence conservation of the target fragment renders this PCR assay highly reliable for detecting the VZV sequence. Only one VZV strain isolated from a patient with varicella during pregnancy exhibited a GGA to GAA point mutation at codon 46 of gene 4, culminating in the non-conservative substitution of Ser with Phe. The predicted secondary structure of the mutant polypeptide portrayed a radical alteration, which may influence its function in transcriptional activation.
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Affiliation(s)
- V T Chow
- Department of Microbiology, Faculty of Medicine, National University of Singapore, Republic of Singapore
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Fon WC, Lim KP, Ratnavelu K, Sawey PM. 29-state R-matrix investigation of resonances in e--He scattering at low energies: 1 (1)S-3 (3),1S and 1 (1)S-4 (3),1S excitation cross sections. Phys Rev A 1994; 50:4802-4811. [PMID: 9911477 DOI: 10.1103/physreva.50.4802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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