| 1. |
- Jahan, Mahabuba, et al.
(författare)
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The development of a GPR44 targeting radioligand [11C]AZ12204657 for in vivo assessment of beta cell mass.
- 2018
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Ingår i: EJNMMI Research. - : Springer Science and Business Media LLC. - 2191-219X. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The G-protein-coupled receptor 44 (GPR44) is a beta cell-restricted target that may serve as a marker for beta cell mass (BCM) given the development of a suitable PET ligand.METHODS: The binding characteristics of the selected candidate, AZ12204657, at human GPR44 were determined using in vitro ligand binding assays. AZ12204657 was radiolabeled using 11C- or 3H-labeled methyl iodide ([11C/3H]CH3I) in one step, and the conversion of [11C/3H]CH3I to the radiolabeled product [11C/3H]AZ12204657 was quantitative. The specificity of radioligand binding to GPR44 and the selectivity for beta cells were evaluated by in vitro binding studies on pancreatic sections from human and non-human primates as well as on homogenates from endocrine and exocrine pancreatic compartments.RESULTS: The radiochemical purity of the resulting radioligand [11C]AZ12204657 was > 98%, with high molar activity (MA), 1351 ± 575 GBq/μmol (n = 18). The radiochemical purity of [3H]AZ12204657 was > 99% with MA of 2 GBq/μmol. Pancreatic binding of [11C/3H]AZ12204657 was co-localized with insulin-positive islets of Langerhans in non-diabetic individuals and individuals with type 2 diabetes (T2D). The binding of [11C]AZ12204657 to GPR44 was > 10 times higher in islet homogenates compared to exocrine homogenates. In human islets of Langerhans GPR44 was co-expressed with insulin, but not glucagon as assessed by co-staining and confocal microscopy.CONCLUSION: We radiolabeled [11C]AZ12204657, a potential PET radioligand for the beta cell-restricted protein GPR44. In vitro evaluation demonstrated that [3H]AZ12204657 and [11C]AZ12204657 selectively target pancreatic beta cells. [11C]AZ12204657 has promising properties as a marker for human BCM.
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| 2. |
- Jia, Zhaobao, et al.
(författare)
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Are the elderly more vulnerable to psychological impact of natural disaster? A population-based survey of adult survivors of the 2008 Sichuan earthquake
- 2010
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Ingår i: BMC Public Health. - : BioMed Central. - 1471-2458. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The association between ages and psychological impact of natural disasters has not been well characterized. A population-based study was conducted 15 months after the 2008 Sichuan earthquake to assess whether elderly survivors were more likely to develop posttraumatic stress disorder (PTSD) and general psychiatric morbidity.METHODS: A population-based survey of 327 survivors (152 elders, 175 younger adults) was conducted in severely affected areas by the earthquake, using a multi-stage systematic sampling design.RESULTS: Compared with the younger adult survivors, the elderly were more likely to have symptoms of PTSD (22.5% vs. 8.0%, p = 0.001) and general psychiatric morbidity (42.0% vs. 25.4%, p = 0.003). Risk factors, such as being elderly, having been in serious danger, having lost family members, and having felt guilt concerning one's death or injury were significantly associated with developing PTSD; being elderly, having family members or friends seriously injured, and having felt guilt concerning one's death or injury were significantly associated with developing general psychiatric morbidity. Utilization of mental health services is strongly associated with the decreased risk for developing both of the symptoms.CONCLUSION: Compared with the younger adults, the elderly survivors were more likely to develop PTSD and general psychiatric morbidity. More mental health services should be distributed to the elderly and groups at particular risk, to ensure their smooth mental health reconstruction after the earthquake.
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| 3. |
- Luo, Yifei, et al.
(författare)
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Technology Roadmap for Flexible Sensors
- 2023
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Ingår i: ACS Nano. - : American Chemical Society. - 1936-0851 .- 1936-086X. ; 17:6, s. 5211-5295
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Forskningsöversikt (refereegranskat)abstract
- Humans rely increasingly on sensors to address grand challenges and to improve quality of life in the era of digitalization and big data. For ubiquitous sensing, flexible sensors are developed to overcome the limitations of conventional rigid counterparts. Despite rapid advancement in bench-side research over the last decade, the market adoption of flexible sensors remains limited. To ease and to expedite their deployment, here, we identify bottlenecks hindering the maturation of flexible sensors and propose promising solutions. We first analyze challenges in achieving satisfactory sensing performance for real-world applications and then summarize issues in compatible sensor-biology interfaces, followed by brief discussions on powering and connecting sensor networks. Issues en route to commercialization and for sustainable growth of the sector are also analyzed, highlighting environmental concerns and emphasizing nontechnical issues such as business, regulatory, and ethical considerations. Additionally, we look at future intelligent flexible sensors. In proposing a comprehensive roadmap, we hope to steer research efforts towards common goals and to guide coordinated development strategies from disparate communities. Through such collaborative efforts, scientific breakthroughs can be made sooner and capitalized for the betterment of humanity.
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| 4. |
- Stepanov, Vladimir, et al.
(författare)
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Development of [C-11]/[H-3-1]THK-5351-A potential novel carbon-11 tau imaging PET radioligand
- 2017
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Ingår i: Nuclear Medicine and Biology. - : Elsevier BV. - 0969-8051 .- 1872-9614. ; 46, s. 50-53
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Due to the rise in the number of patients with dementia the imperative for finding new diagnostic and treatment options becomes ever more pressing. While significant progress has been made in PET imaging of A beta aggregates both in vitro and in vivo, options for imaging tau protein aggregates selectively are still limited. Based on the work previously published by researchers from the Tohoku University, Japan, that resulted in the development of [F-18]THK-5351, we have undertaken an effort to develop a carbon-11 version of the identical structure - [C-11]THK-5351. In parallel, THK-5351 was also labeled with tritium ([H-3]THK-5351) for use in in vitro autoradiography (ARG). Methods: The carbon -11 labeling was performed starting with di-protected enantiomeric pure precursor-tertbutyl 5-(6-( (2S)-3-fluoro-2-(tetrahydro-2H-Pyran-2-yloxy)proPoxy)quinolin-2-yl)pyridin-2-yl carbamate, which was reacted with [C-11]MeI, using DMF as the solvent and NaH as base, followed by deprotection with trifluoroacetic acid/water mixture, resulting in enantiomerically pure carbon-11 radioligand,[C-11]THK-5351 (S)-1-fluoro-3-(2-(6-([C-11]methylamino)pyridin-3-yl)quinolin-6-yloxy)propan-2-ol. Tritium labeling and purification of [H-3]THK-5351 were undertaken using similar approach, resulting in [H-3]THK-5351 with RCP >99.8% and specific radioactivity of 13 GB q/mu mol. Results: [C-11]THK-5351 was produced in good yield (1900 +/- 355 MBq), specific radioactivity (SRA) (361 +/- 119 GBq/mu rnol at EOS + 20 min) and radiochemical purity (RCP) (>99.8%), with enantiomeric purity of 98.7%. [H-3]TM-5351 was evaluated for ARG of tau binding in post-mortem human brain tissue using cortical sections from one AD patient and one control subject. [H-3]THK-5351 binding density was higher in the AD patient compared to the control subject, the binding was displaced by unlabeled THK-5351 confirming specific [H-3] THK-5351 binding. (C) 2016 Elsevier Inc. All rights reserved.
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