BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CERN//INDICO//EN BEGIN:VEVENT SUMMARY:Ps in solutions - could be of help for PET and detection of carcin ogens? DTSTART;VALUE=DATE-TIME:20211009T095000Z DTEND;VALUE=DATE-TIME:20211009T101000Z DTSTAMP;VALUE=DATE-TIME:20260815T031907Z UID:indico-contribution-13-305@indico.koza.if.uj.edu.pl DESCRIPTION:Speakers: Sergey Stepanov (NRC "Kurchatov Institute" - Institu te for Theoretical and Experimental Physics)\nstepanov@itep.ru \n\nIt is k nown that the concentration of the dissolved oxygen in malignant tumors is much lower than in healthy tissues. Therefore\, cancer cells permanently live in conditions of oxygen starvation. On the other hand\, dissolved oxy gen efficiently shortens the lifetime of the ortho-Ps atom. It takes place because\, firstly\, oxygen may oxidize Ps (taking away an electron from i t and converting Ps into a “free” positron). Secondly\, since the O2 m olecule is paramagnetic\, it is able to induce the process of ortho-to-par a Ps spin conversion. Both of these effects reduce the Ps lifetime in liqu ids. This means that the lifetime of the Ps in healthy tissues will be sho rter than in malignant ones. This relationship between the ortho-Ps lifeti me and the concentration of the dissolved О2 can be used to develop a new \, additional method for detecting tumors using modern positron emission t omographs [1\, 2].\n\nIt is recognized that one of the main causes of canc er is chemical carcinogens. Physicochemical methods for determining the ca rcinogenic activity of substances are based on the fact that most of carci nogens are\, in particular\, effective electron scavengers. However\, it i s known that track electrons\, generated by ionizing slowing down of the f ast positrons when they pass through a medium\, are the main precursors of the positronium atom (Ps). We have shown that the complete inhibition of the Ps formation in a cellular milieu by the test chemical compound can se rve as an indication of its carcinogenic properties.\n\nThis approach is s imilar to what was done by G. Bakale using nanosecond pulsed radiolysis se tup in 80’s. The advantages of the positron approach over the Bakale’s method are reduced to simplicity\, speed and economic benefit.\n\nThe sim plest model is proposed for interpretation of the carried out experiments on Ps inhibition\, oxidation and ortho-para conversion.\n\n\n[1] S.V. Ste panov\, V.M. Byakov\, P.S. Stepanov "Positronium in Biosystems and Medici ne: A New Approach to Tumor Diagnostics Based on Correlation between Oxyge nation of Tissues and Lifetime of the Positronium Atom" Physics of Wave Ph enomena\, V. 29(2)\, 174-179 (2021) DOI: 10.3103/S1541308X21020138\n[2] P.S. Stepanov\, F.A. Selim\, S.V. Stepanov\, A.V. Bokov\, O.V. Ilyukhina\, G. Duplatre\, V.M. Byakov "Interaction of positronium with dissolved oxy gen in liquids"\, Physical Chemistry Chemical Physics\, V. 22\, 5123-5131 (2020) doi.org/10.1039/C9CP06105C\n[3] Vsevolod M. Byakov\, Sergey V. Ste panov "Detection of carcinogenic and anticancerogenic properties of chemi cals by means of the positron annihilation lifetime spectroscopy". RENSIT\ , 12(1):115-128 (2020)\; DOI: 10.17725/rensit.2020.12.115\n\nhttps://indic o.koza.if.uj.edu.pl/event/4/contributions/305/ LOCATION:Theranostics Center / on-line URL:https://indico.koza.if.uj.edu.pl/event/4/contributions/305/ END:VEVENT BEGIN:VEVENT SUMMARY:First three-photon positronium image obtained with the J-PET scann er: towards multi-photon imaging DTSTART;VALUE=DATE-TIME:20211009T105000Z DTEND;VALUE=DATE-TIME:20211009T111000Z DTSTAMP;VALUE=DATE-TIME:20260815T031907Z UID:indico-contribution-13-267@indico.koza.if.uj.edu.pl DESCRIPTION:Speakers: Aleksander Gajos (Jagellonian University\, Kraków\, Poland)\n**First three-photon positronium image obtained with the J-PET s canner: towards multi-photon imaging**\n---------------------------------- --------------------------------------\n\nAleksander Gajos\non behalf of t he J-PET Collaboration\nFaculty of Physics\, Astronomy and Applied Compute r Science\, Jagiellonian University\,\nS. Łojasiewicza 11\, 30-348\, Krak ów\, Poland\ne-mail: aleksander.gajos@uj.edu.pl\n\nPositronium atoms\, i. e. bound states of electron and positron\, produced by up to 40% of positr ons in conventional Positron Emission Tomography (PET) scans\, are present ly not utilized for imaging. However\, their annihilations may carry essen tial information complementary to the functional imaging of PET [1]. \n \n The recently proposed technique of multi-photon imaging with the Jagiellon ian Positron Emission Tomography (J-PET) scanner [2] aims at spatially-res olved determination of positronum properties in the examined volume. To da te\, use of two-photon positronium annihilations to obtain a positronium l ifetime image was demonstrated [2]. Another conceivable modality comprises obtaining an image as a map of the ratio of two-photon to three-photon an nihilations of positronium\, for which spatial reconstruction of three-ph oton annihilations of the positronium trilet state is required.\n\nThe tal k will discuss the capability of the J-PET scanner to record\, identify an d reconstruct three-photon positronium annihilations. Methodolgy and resul ts of the first test of three-photon imaging with J-PET [3] will be presen ted\, including the first image of an object of extensive dimensions obtai ned solely using ortho-positronium annihilations into three photons. Perfo rmance of this imaging method will be discussed and compared to that of co nventional two-photon imaging with the same setup.\n \n**References:**\n\n [1] P. Moskal\, B. Jasińska\, E. Ł. Stępień and S. D. Bass\, „Positr onium in medicine and biology”\, Nat. Rev. Phys.\, vol. 1\, pp. 527-529\ , 2019\, doi: 10.1038/s42254-019-0078-7.\n\n[2] P. Moskal\, et al.\, „Po sitronium imaging with the novel multi-photon PET scanner”\, Science Adv ances\, to be published.\n\n[3] Moskal et al.\, „Testing CPT symmetry in ortho-positronium decays with positronium annihilation tomography”\, Na t. Commun.\, vol. 12\, pp. 5658\, 2021\, doi:10.1038/s41467-021-25905-9.\n \nhttps://indico.koza.if.uj.edu.pl/event/4/contributions/267/ LOCATION:Theranostics Center / on-line URL:https://indico.koza.if.uj.edu.pl/event/4/contributions/267/ END:VEVENT BEGIN:VEVENT SUMMARY:Whole gamma imaging: PET combined with Compton imaging DTSTART;VALUE=DATE-TIME:20211009T093000Z DTEND;VALUE=DATE-TIME:20211009T095000Z DTSTAMP;VALUE=DATE-TIME:20260815T031907Z UID:indico-contribution-13-239@indico.koza.if.uj.edu.pl DESCRIPTION:Speakers: Taiga Yamaya (National Institutes for Quantum and Ra diological Science and Technology (QST))\nWhole gamma imaging (WGI) is a novel concept of combined PET with Compton imaging. An additional detector ring\, which is used as the scatterer\, is inserted in a conventional PET ring so that single gamma rays can be detected by the Compton imaging met hod. In addition to a conventional PET mode\, Compton imaging (single-gamm a mode) is possible. Further large impact can be expected for triple gamma emitters such as 44Sc (about 4 h half-life)\, that emits a positron and a 1157 keV gamma ray almost at the same time (triple-gamma mode). In princi ple\, only a few decays would be enough to localize the source position by calculating intersection points of a 511 keV line-of-response with a 1157 keV Compton cone. We developed a prototype of the WGI system [1][2]. All interaction events were recorded as list-mode data\, and event selection s uch as coincidence detection was done in software. We measured a 137Cs poi nt source in the single-gamma mode and a 22Na point source with convention -al coincidence detection. The 22Na point source was also used to demonstr ate the triple gamma mode as it emits a 1275 keV gamma ray after a positro n decay. In the single-gamma mode\, spatial resolution for the 137Cs point source obtained by 3D list-mode OSEM was 4.4 mm FWHM (8 cm off-center) - 13.1 mm FWHM (center). Spatial resolution values for the 22Na point source \, obtained by the absorber-absorber coincidence and the scatterer-scatter er coincidence\, were almost the same (below 2 mm). In the triple gamma mo de\, where only simple backprojection was applied and no image reconstruct ion algorithm was applied\, spatial resolution for the 22Na point source w as 4.8 mm FWHM (8 cm off-center) - 5.7 mm FWHM (center). WGI with 44Sc can be also used to measure positronium lifetime [3]\, which may enable a new field of “quantum PET (Q-PET)”. One possible application of Q-PET is hypoxia imaging of tumor patients [4].\n\nReferences\n[1] E. Yoshida\, H. Tashima\, K. Nagatsu\, et al.\, "Whole gamma imaging: a new concept of PET combined with Compton imaging\," Phys. Med. Biol.\, 65\, 125013\, 2020.\n [2] H. Tashima\, E. Yoshida\, H. Wakizaka\, et al.\, "3D Compton image rec onstruction method for whole gamma imaging\," Phys. Med. Biol.\, 65\, 2250 38\, 2020.\n[3] P. Moskal\, B. Jasińska\, E.Ł. Stępień\, et al.\, “P ositronium in medicine and biology\,” Nat. Rev. Phys. 1\, 527-529\, 2019 .\n[4] K. Shibuya\, H. Saito\, F. Nishikido\, et al.\, "Oxygen sensing abi lity of positronium atom for tumor hypoxia imaging\," Commun. Phys. 3\, 17 3\, 2020.\n\nhttps://indico.koza.if.uj.edu.pl/event/4/contributions/239/ LOCATION:Theranostics Center / on-line URL:https://indico.koza.if.uj.edu.pl/event/4/contributions/239/ END:VEVENT BEGIN:VEVENT SUMMARY:How quantum entanglement can help in theranostics? DTSTART;VALUE=DATE-TIME:20211009T103000Z DTEND;VALUE=DATE-TIME:20211009T105000Z DTSTAMP;VALUE=DATE-TIME:20260815T031907Z UID:indico-contribution-13-240@indico.koza.if.uj.edu.pl DESCRIPTION:Speakers: Beatrix Hiesmayr (University of Vienna)\nQuantum ent anglement is a phenomenon that shows the every working at small scales whi ch differs strongly from the laws governing our daily world. Reading out t his quantum information has the potential to reveal unknown processes and connections and on the long term to provide doctors with quantum indicator s. This contribution focuses on the entanglement of two and three gammas e mitted from positronium atoms\, which is a frequent process in human being s undergoing e.g. a PET-scan (PET=Positron Emission Tomography). Theory pr edicts these two or three photon events to be entangled\, more precisely i n very special types of entanglement [1\,2]. With the cutting-edge technol ogy developed by the J-PET collaboration at the Jagiellonian University th e detection of entanglement at this high energy scales is -for the first t ime- in reach [3]. This talk will give an overview over the progress made. Particularly\, novel software developments [4] are needed to tackle this involved problem. \n\n[1] B.C. Hiesmayr and P. Moskal\, Sci Rep 9\, 8166 ( 2019).\n[2] B.C. Hiesmayr and P. Moskal\, Sci Rep 7\, 15349 (2017).\n[3] P . Moskal\, N. Krawczyk\, B. C. Hiesmayr\, M. Bała\, C. Curceanu\, E. Czer winski\, K. Dulski\, A. Gajos\, M. Gorgol\, R. Del Grande\, B. Jasinska\, K. Kacprzak\, L. Kapłon\, D. Kisielewska\, K. Klimaszewski\, G. Korcyl\, P. Kowalski\, T. Kozik\, W. Krzemien\, E. Kubicz\, M. Mohammed\, Sz. Nied źwiecki\, M. Pałka\, M. Pawlik-Niedźwiecka\, L. Raczynski\, J. Raj\, Z. Rudy\, S. Sharma\, M. Silarski\, Shivani\, R. Y. Shopa\, M. Skurzok\, W. Wislicki\, B. Zgardzinska\, Eur. Phys. J. C 78\, 970 (2018).\n[4] W. Krze mień\, A. Gajos\, K. Kacprzak\, K. Rakoczy and G. Korcyl\, SoftwareX 11\, 100487 (2020).\n\nhttps://indico.koza.if.uj.edu.pl/event/4/contributions /240/ LOCATION:Theranostics Center / on-line URL:https://indico.koza.if.uj.edu.pl/event/4/contributions/240/ END:VEVENT BEGIN:VEVENT SUMMARY:Oxygen sensing ability of positronium DTSTART;VALUE=DATE-TIME:20211009T101000Z DTEND;VALUE=DATE-TIME:20211009T103000Z DTSTAMP;VALUE=DATE-TIME:20260815T031907Z UID:indico-contribution-13-238@indico.koza.if.uj.edu.pl DESCRIPTION:Speakers: Kengo Shibuya (University of Tokyo\, Japan)\nPositro nium (Ps) is an exotic atom consisting of a positron and an electron\, and around 1011 Ps atoms form in the human body during a PET scan. We have di scussed little Ps in PET because its formation does not change the spatial information obtained by PET\; Most Ps annihilates into back-to-back gamma -ray photons. However\, Ps can provide other unique information due to the delay of the gamma-ray emission as long as its lifetime. The lifetime var ies according to the chemical and physical environment for Ps. For example \, the lower dissolved oxygen concentration (pO2)\, the longer a Ps atom s urvives in solutions. This is because of the unpaired electrons in the O2 molecule that enhance Ps annihilation via the electron exchange interactio n. Knowing pO2 distribution is important for cancer patients because hypox ic cells are often resistant to radiotherapy as well as chemotherapy.\n\nM oskal *et al.* named the new concept of PET as “Ps imaging [1]\,” and they also found that the Ps lifetime differs between healthy and cancer ce lls [2]. The difference may come from a combination of several chemical an d physical conditions\, but how each factor changes the Ps lifetime is a c hallenging matter to be understood. Some efforts have revealed how O2 mole cules reduce Ps lifetime. Stepanov [3] found a positive correlation betwee n the pO2 and Ps annihilation rate (the inverse of the lifetime) in water. Furthermore\, we found good linearity between them by accumulating 50 tim es larger number of counts\, as shown in Fig. 1 [4]. This line is namely c alibration line for Ps as an oxygen sensor\, and this result indicates a p ossibility of Ps as a hypoxia biomarker candidate. In other words\, during a PET scan\, 1011 nanosized sensors for O2 are spontaneously created in v ivo\, and it is worth trying to read the indicator for improving cancer tr eatments.\n\n**Fig. 1** pO2 vs Ps decay rate: squares (Lee [5])\, triangle s (Stepanov [3])\, and circles (Shibuya [4]). (see at *https://www.nature. com/articles/s42005-020-00440-z/figures/3*)\n\n**References**\n[1] P. Mosk al\, *et al*.\, *Nature Rev. Phys*.\, **1**\, 527‒9 (2019).\n[2] P. Mosk al\, *et al*.\, *bioRxiv* (2021). (doi: 10.1101/2021.08.05.455285)\n[3] P. S. Stepanov\, *et al*.\, *Phys. Chem. Chem. Phys*. **22**\, 5123 (2020).\ n[4] K. Shibuya\, *et al*.\, *Commun. Phys*.\, **3**\, 173 (2020).\n[5] J. Lee\, *et al*.\, *J. Chem. Phys*. **44**. 2506 (1966).\n\nhttps://indico. koza.if.uj.edu.pl/event/4/contributions/238/ LOCATION:Theranostics Center / on-line URL:https://indico.koza.if.uj.edu.pl/event/4/contributions/238/ END:VEVENT BEGIN:VEVENT SUMMARY:Nano-theranostics: harnessing nanoscale functionality for next-gen eration theranostic technologies DTSTART;VALUE=DATE-TIME:20211009T091000Z DTEND;VALUE=DATE-TIME:20211009T093000Z DTSTAMP;VALUE=DATE-TIME:20260815T031907Z UID:indico-contribution-13-236@indico.koza.if.uj.edu.pl DESCRIPTION:Speakers: Zdenka Kuncic (University of Sydney\, Australia)\n** Abstract**\nNanoscale geometric confinement changes the properties of mate rials. The most immediate effect is an enhancement in the surface area to volume ratio\, which results in faster surface chemistry reaction rates\, a property exploited in various nanomedicine approaches. Arguably more int eresting\, however\, are changes in physical properties\, including optica l\, electrical and magnetic properties. In this talk\, I will focus on how the superparamagnetic properties of iron oxide nanoparticles can be harne ssed to enhance imaging with PET-MRI and to enable novel image-guided\, tu mour-targeting nano-theranostic strategies. Super-Paramagnetic Iron Oxide Nanoparticles (SPIONs)\, which enhance MRI image contrast\, were labelled with a PET isotope (Zr-89) to demonstrate their use in PET-MRI [1]. Moreov er\, it was found that the SPIONs localise the emitted positrons sufficien tly to improve PET image resolution in PET-MRI [2]. Such SPIONs were also labelled with a range of clinical therapeutic (Y-90) and theranostic (Lu-1 77\, Cu-64/67) radioisotopes\, thus demonstrating their potential for can cer nano-theranostics leveraging clinical imaging technologies.\n\n**Refer ences**\n[1] Y. Gholami et al. A radio-nano-platform for T1/T2 dual-mode P ET-MR imaging. Int. J. Nanomed. 15\, 1253 (2020) doi.org/10.2147/IJN.S2419 71 \n[2] Y. Gholami et al. Positron annihilation localization by nanoscale magnetization. Sci. Rep. 10\, 20262 (2020) doi.org/10.1038/s41598-020-769 80-9\n[3] Y. Gholami et al. A chelate-free nano-platform for incorporation of diagnostic and therapeutic isotopes. Int. J. Nanomed. 15\, 31 (2020) d oi.org/10.2147/IJN.S227931\n\nhttps://indico.koza.if.uj.edu.pl/event/4/con tributions/236/ LOCATION:Theranostics Center / on-line URL:https://indico.koza.if.uj.edu.pl/event/4/contributions/236/ END:VEVENT END:VCALENDAR