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Visual analytics (VA) is a visually assisted exploratory analysis approach in which knowledge discovery is executed interactively between the user and system in a human-centered manner. The purpose of this study is to develop a method for the VA of set data aimed at supporting knowledge discovery and member selection. A typical target application is a visual support system for team analysis and member selection, by which users can analyze past teams and examine candidate lineups for new teams. Because there are several difficulties, such as the combinatorial explosion problem, developing a VA system of set data is challenging. In this study, we first define the requirements that the target system should satisfy and clarify the accompanying challenges. Then we propose a method for the VA of set data, which satisfies the requirements. The key idea is to model the generation process of sets and their outputs using a manifold network model. The proposed method visualizes the relevant factors as a set of topographic maps on which various information is visualized. Furthermore, using the topographic maps as a bidirectional interface, users can indicate their targets of interest in the system on these maps. We demonstrate the proposed method by applying it to basketball teams, and compare with a benchmark system for outcome prediction and lineup reconstruction tasks. Because the method can be adapted to individual application cases by extending the network structure, it can be a general method by which practical systems can be built., This is accepted manuscript in Decision Support Systems. The codes of prototype system are available on https://github.com/furukawa-laboratory/demo-visual-analytics-set-data

Introduction: [11C]PBB3 is a clinically used positron emission tomography (PET) probe for in vivo imaging of tau pathology in the brain. Our previous study showed that [11C]PBB3 was rapidly decomposed to a polar radiometabolite in the plasma of mice. For the pharmacokinetic evaluation of [11C]PBB3 it is important to elucidate the characteristics of radiometabolites. In this study, we identified the chemical structure of a major radiometabolite of [11C]PBB3 and proposed the metabolic pathway of [11C]PBB3. Methods: Carrier-added [11C]PBB3 was injected into a mouse for in vivo metabolite analysis. The chemical structure of a major radiometabolite was identified using LC–MS. Mouse and human liver microsomes and liver S9 samples were incubated with [11C]PBB3 in vitro. In silico prediction software was used to assist in the determination of the metabolite and metabolic pathway of [11C]PBB3. Results: In vivo analysis showed that the molecular weight of a major radiometabolite of [11C]PBB3, which was called as [11C]M2, was m/z 390 [M+H+]. In vitro analysis assisted by in silico prediction showed that [11C]M2, which was not generated by cytochrome P450 enzymes (CYPs), was generated by sulfated conjugation mediated by a sulfotransferase. Conclusion: The major radiometabolite, [11C]M2, was identified as a sulfated conjugate of [11C]PBB3. [11C]PBB3 was metabolized mainly by a sulfotransferase and subsidiarily by CYPs.

Objectives: Translocator protein (18 kDa) (TSPO), a nucleus-encoded mitochondrial target transmembrane protein, has been indicated as an active participant in the modulation of mitochondrial function. PET using radiolabeled TSPO probes has allowed non-invasive and reliable investigation of TSPO in neuropathological damages of experimental animals and humans. Many PET probes for TSPO imaging have been developed. Among them, [18F]FEDAC has potent binding affinity and selectivity for TSPO [1], high signal to neuroinflammation [2], and high sensitivity and specificity for detection of fatty liver diseases progression [3]. We had previously synthesized [18F]FEDAC by reaction of desmethyl-precursor with [18F]fluoroethyl bromide at two steps using a modified 18F-labelling synthesizer developed in our institute [1-3]. In this study, we simplified the synthesis of [18F]FEDAC by direct 18F-fluorination using a typical 18F-labelling synthesizer to transfer the preparation of [18F]FEDAC to other institutes toward multicenter clinical study. Methods: Tosylate-precursor for radiosynthesis of [18F]FEDAC was synthesized according to the procedures, as shown in Fig. 1. [18F]FEDAC was prepared by heating the tosylate-precursor with 18F- in DMSO at 110 ⁰C for 10-15 min. Results: Tosylate-precursor of [18F]FEDAC was successfully synthesized from desmethyl-precursor. [18F]FEDAC was obtained with sufficient radioactivity and suitable quality for injection in clinical application. The synthesis of [18 F]FEDAC was reproduceble to achieve >740 MBq, >300 GBq/μmol and >97% of radiochemical purity within 70 min of an overall synthesis time. All other analytical results were in compliance with our in-house quality control and assurance specifications. Conclusions: We successfully synthesized [18F]FEDAC by fluorination of the tosylate-precursor with 18F- using onepot 18F-labelling synthesizer. This radioligand will be used in clinical study. References: [1] Yanamoto K, et al (2009), Bioorg Med Chem Lett, 19, 1707-10. [2] Yui J, et al (2010), J Nucl Med, 51, 1301-9. [3] Xie L, et al (2012), J Hepatol, 57, 1076-82., 21st International Symposium on Radiopharmaceutical Sciences