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Nobuo Suzui, Yong-Gen Yin, Satomi Ishii, Hitoshi Sekimoto, Naoki Kawachi
BACKGROUND: Positron imaging can be used to non-destructively visualize the dynamics of a positron-emitting radionuclide in vivo, and is therefore a tool for understanding the mechanisms of nutrient transport in intact plants. The transport of zinc, which is one of the most important nutrient elements for plants, has so far been visualized by positron imaging using (62)Zn (half-life: 9.2 h), which is manufactured in the limited number of facilities that have a cyclotron. In contrast, the positron-emitting radionuclide (65)Zn (half-life: 244 days) is commercially available worldwide...
2017: Plant Methods
A R Liboff, C Poggi, P Pratesi
A helitetrahedral model has been proposed to help explain reports of low-frequency oscillations in pure water following electromagnetic excitation at the hydronium ion cyclotron resonance frequency. The Lorentz force and the intrinsic structure constrain the motion of the H3O(+) ion so that it enjoys a unique form of proton-hopping, one whose path is helical. This model may also explain the numerous previously observed cyclotron resonance (ICR) biological couplings for cations other than hydronium by merely substituting hydrogen-bonded versions of these for hydronium in the tetrahedral structure...
May 19, 2017: Electromagnetic Biology and Medicine
Aviral Singh, Nicholas P van der Meulen, Cristina Müller, Ingo Klette, Harshad R Kulkarni, Andreas Türler, Roger Schibli, Richard P Baum
(44)Sc is a promising positron emission tomography (PET) radionuclide (T1/2 = 4.04 hours, Eβ+average = 632 keV) and can be made available, using a cyclotron production route, in substantial quantities as a highly pure product. Herein, the authors report on a first-in-human PET/CT study using (44)Sc-DOTATOC prepared with cyclotron-produced (44)Sc. The production of (44)Sc was carried out through the (44)Ca(p,n)(44)Sc nuclear reaction at Paul Scherrer Institut, Switzerland. After separation, (44)Sc was shipped to Zentralklinik Bad Berka, Germany, where radiolabeling was performed, yielding radiochemically pure (44)Sc-DOTATOC...
May 2017: Cancer Biotherapy & Radiopharmaceuticals
Mohammad B Haskali, Victor W Pike
Positron-emission tomography (PET) is an immensely important imaging modality in biomedical research and drug development but must use selective radiotracers to achieve biochemical specificity. Such radiotracers are usually labeled with carbon-11 (t1/2 =20 min) or fluorine-18 (t1/2 =110 min), but these are only available from cyclotrons in a few simple chemical forms. [(18) F]Fluoroform has emerged for labeling tracers in trifluoromethyl groups but is severely limited in utility by low radioactivity per mass (low molar activity)...
May 17, 2017: Chemistry: a European Journal
M Scott, R G T Zegers, R Almus, Sam M Austin, D Bazin, B A Brown, C Campbell, A Gade, M Bowry, S Galès, U Garg, M N Harakeh, E Kwan, C Langer, C Loelius, S Lipschutz, E Litvinova, E Lunderberg, C Morse, S Noji, G Perdikakis, T Redpath, C Robin, H Sakai, Y Sasamoto, M Sasano, C Sullivan, J A Tostevin, T Uesaka, D Weisshaar
The (^{10}Be,^{10}B^{*}[1.74  MeV]) charge-exchange reaction at 100  AMeV is presented as a new probe for isolating the isovector (ΔT=1) nonspin-transfer (ΔS=0) response of nuclei, with ^{28}Si being the first nucleus studied. By using a secondary ^{10}Be beam produced by fast fragmentation of ^{18}O nuclei at the NSCL Coupled Cyclotron Facility, applying the dispersion-matching technique with the S800 magnetic spectrometer to determine the excitation energy in ^{28}Al, and performing high-resolution γ-ray tracking with the Gamma-Ray Energy Tracking In-beam Nuclear Array (GRETINA) to identify the 1022-keV γ ray associated with the decay from the 1...
April 28, 2017: Physical Review Letters
Fabrice G Siméon, William J Culligan, Shuiyu Lu, Victor W Pike
Pd(0)-mediated coupling between iodoarenes, [(11)C]carbon monoxide and aryltributylstannanes has been used to prepare simple model [(11)C]aryl ketones. Here, we aimed to label four 2-aminoethylbenzofuran chemotype based molecules ([(11)C]1-4) in the carbonyl position, as prospective positron emission tomography (PET) radioligands for the histamine subtype 3 receptor (H3R) by adapting this methodology with use of aryltrimethylstannanes. Radiosynthesis was successfully performed on a platform equipped with a mini-autoclave and a liquid handling robotic arm, within a lead-shielded hot-cell...
May 12, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Thomas Manning, Sydney Plummer, Rechelle Woods, Greg Wylie, Dennis Phillips, Logan Krajewski
The copper(II) cation, sucrose, and hydroxychloroquine were complexed with the chemotherapy agent paclitaxel and studied for medicinal activity. Data (GI50, LD50) from single dose and five dose National Cancer Institute sixty cell line panels are presented. Analytical measurements of different complexes were made using Nuclear Magnetic Resonance ((1)H NMR), Matrix Assisted Laser Desorption Ionization-Time of Flight-Mass Spectrometry (MALDI-TOF-MS) and Fourier Transform-Ion Cyclotron Resonance (FT-ICR). Molecular modeling is utilized to better understand the impact that species could have on physical parameters associated with Lipinski's Rule of Five, such as logP and TPSA...
April 22, 2017: Bioorganic & Medicinal Chemistry Letters
Julia Raeke, Oliver J Lechtenfeld, Bettina Seiwert, Till Meier, Christina Riemenschneider, Thorsten Reemtsma
More than 400 new nitrogen containing products were detected upon experimental sunlight photolysis of the pharmaceutical carbamazepine (CBZ) in the presence of dissolved organic matter (DOM) by Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). These products were presumably formed through covalent binding of CBZ phototransformation products with DOM molecules. About 50% of these newly formed bound residues contained one nitrogen atom and had a molecular mass between 375 and 525 Da, which was 150 to 200 Da higher than for an average DOM molecule...
May 5, 2017: Environmental Science & Technology
Anu Teearu, Signe Vahur, Toomas Rodima, Koit Herodes, Werner Bonrath, Thomas Netscher, Sofja Tshepelevitsh, Aleksander Trummal, Märt Lõkov, Ivo Leito
Matrix-assisted laser desorption/ionization (MALDI) is a mass spectrometry (MS) ionization technique suitable for a wide variety of sample types including highly complex ones such as natural resinous materials. Coupled with Fourier transform ion cyclotron resonance (FT-ICR) mass analyzer, which provides mass spectra with high resolution and accuracy, the method gives a wealth of information about the composition of the sample. One of the key aspects in MALDI-MS is the right choice of matrix compound. We have previously demonstrated that 2,5-dihydroxybenzoic acid (DHB) is suitable for the positive ion mode analysis of resinous samples...
May 4, 2017: Journal of Mass Spectrometry: JMS
Tordis J Dahle, Anne Marit Rykkelid, Camilla H Stokkevåg, Andrea Mairani, Andreas Görgen, Nina J Edin, Eivind Rørvik, Lars Fredrik Fjæra, Eirik Malinen, Kristian S Ytre-Hauge
BACKGROUND: In order to determine the relative biological effectiveness (RBE) of protons with high accuracy, radiobiological experiments with detailed knowledge of the linear energy transfer (LET) are needed. Cell survival data from high LET protons are sparse and experiments with low energy protons to achieve high LET values are therefore required. The aim of this study was to quantify LET distributions from a low energy proton beam by using Monte Carlo (MC) simulations, and to further compare to a proton beam representing a typical minimum energy available at clinical facilities...
June 2017: Acta Oncologica
Hassan Sabzyan, Maryam Kowsar
A nano-flow is induced by applying gigahertz rotating electric fields (EFs) of different strengths and frequencies on a carbon nanotorus filled with water molecules, using molecular dynamics simulations. This nano-flow, which may also be regarded as a molecular cyclotron motion, needs a rising time to establish and to follow the rotating EF depending on the applied EF strength and frequency. For establishment of a steady cyclotron motion in the carbon nanotorus, EFs of higher strengths and lower frequencies are required...
May 17, 2017: Physical Chemistry Chemical Physics: PCCP
Paolo Benigni, Kathia Sandoval, Christopher J Thompson, Mark E Ridgeway, Melvin A Park, Piero R Gardinali, Francisco Fernandez-Lima
For the first time, trapped ion mobility spectrometry (TIMS) in tandem with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) is applied to the analysis of the low energy water accommodated fraction (WAF) of a crude oil as a function of the exposure to light. The TIMS-FT-ICR MS analysis provided, in addition to the heteroatom series identification, new insights into the WAF isomeric complexity (e.g., [m/z; chemical formula; collision cross section] datasets) for a better evaluation of the degree of chemical and structural photo-induced transformations...
May 1, 2017: Environmental Science & Technology
Fanny Widjaja, Joann P Max, Zhicheng Jin, John J Nash, Hilkka I Kenttämaa
The gas-phase reactivity of two aromatic carbon-centered σ,σ-biradicals (meta-benzyne analogs) and a related monoradical towards small oligonucleotides of differing lengths was investigated in a Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer coupled with laser-induced acoustic desorption (LIAD). The mono- and biradicals were positively charged to allow for manipulation in the mass spectrometer. The oligonucleotides were evaporated into the gas phase as intact neutral molecules by using LIAD...
April 29, 2017: Journal of the American Society for Mass Spectrometry
S Zargan, P Ghafarian, A Shabestani Monfared, A A Sharafi, M Bakhshayeshkaram, M R Ay
BACKGROUND: PET/CT imaging using [18F]-FDG is utilized in clinical oncology for tumor detecting, staging and responding to therapy procedures. Essential consideration must be taken for radiation staff due to high gamma radiation in PET/CT and cyclotron center. The aim of this study was to assess the staff exposure regarding whole body and organ dose and to evaluate environment dose in PET/CT and cyclotron center. MATERIALS AND METHODS: 80 patients participated in this study...
March 2017: Journal of Biomedical Physics & Engineering
S Bongarzone, A Runser, C Taddei, A K Haji Dheere, A D Gee
A novel amide synthesis methodology is described using amines, CO2 and Grignard reagents and Mitsunobu reagents. The method was applied to carbon-11 radiochemistry to label amides using cyclotron-produced [(11)C]CO2. The synthetic utility of the one-pot labelling methodology was demonstrated by producing [(11)C]melatonin. The incorporation of [(11)C]CO2 into [(11)C]melatonin was 36% - determined by radioHPLC 2 min post [(11)C]CO2 delivery.
May 9, 2017: Chemical Communications: Chem Comm
Alessandra Boschi, Petra Martini, Micol Pasquali, Licia Uccelli
(99m)Tc is the most commonly used radionuclide in the field of diagnostic imaging, a noninvasive method intended to diagnose a disease, assess the disease state and monitor the effects of treatments. Annually, the use of (99m)Tc, covers about 85% of nuclear medicine applications. This isotope releases gamma rays at about the same wavelength as conventional X-ray diagnostic equipment, and owing to its short half-life (t½ = 6 hours) is ideal for diagnostic nuclear imaging. A patient can be injected with a small amount of (99m)Tc and within 24 hours almost 94% of the injected radionuclide would have decayed and left the body, limiting the patient's radiation exposure...
April 26, 2017: Drug Development and Industrial Pharmacy
Zhineng Hao, Yongguang Yin, Dong Cao, Jingfu Liu
Photochemical halogenation of dissolved organic matter (DOM) may represent an important abiotic process for the formation of natural organobromine compounds (OBCs) and natural organoiodine compounds (OICs) within surface waters. Here we report the enhanced formation of OBCs and OICs by photohalogenating DOM in freshwater and seawater, as well as the noticeable difference in the distribution and composition pattern of newly formed OBCs and OICs. By using negative ion electrospray ionization coupled with Fourier transform ion cyclotron resonance mass spectrometry, various OBCs and OICs were identified during the photohalogenation processes in sunlit waters...
May 5, 2017: Environmental Science & Technology
Hang Wang, Ying Wang, Ge Wang, Lizhi Hong
Matrix-assisted laser desorption/ionization-mass spectrometric imaging (MALDI-MSI) for the analysis of intact hair is a powerful tool for monitoring changes in drug consumption. The embedding of a low drug concentration in the hydrophobic hair matrix makes it difficult to extract and detect, and requires an improved method to increase detection sensitivity. In this study, an MSI method using MALDI-Fourier transform ion cyclotron resonance was developed for direct identification and imaging of olanzapine in hair samples using the positive ion mode...
April 18, 2017: Journal of Pharmaceutical and Biomedical Analysis
Amaury Costagliola, Laurent Venault, Arnaud Deroche, Jackie Vermeulen, Florian Duval, Guillaume Blain, Johan Vandenborre, Massoud Fattahi-Vanani, Nicolas Vigier
Samples of butanal oxime in aqueous nitric acid solutions have been irradiated with the helium ion (4He2+) beam of the CEMHTI (Orléans, France) cyclotrons. The consumption yield of butanal oxime has been measured by gas-chromatography coupled with mass spectrometry. Gaseous products (mainly H2 and N2O) have also been monitored by micro gas-chromatography. Yields of liquid phase products (hydrogen peroxide and nitrous acid) have been determined by colorimetric methods. The influence of nitric acid on the radiation chemical behavior of butanal oxime depends on the nitric acid concentration...
April 24, 2017: Journal of Physical Chemistry. A
Qinghua Xie, Hua Zhu, Feng Wang, Xiangxi Meng, Qiushi Ren, Chuanqin Xia, Zhi Yang
Copper-64 is a useful radioisotope for positron emission tomography (PET). Due to the wide range of applications, the demand of (64)Cu with low metallic impurities is increasing. Here we report a simple method for the efficient production of high specific activity (64)Cu using a cyclotron for biomedical application. We designed new equipment based on the plating of enriched (64)Ni as the target, and used automated ion exchange chromatography to purify copper-64 efficiently after irradiation and dissolution of the target in good radiochemical and chemical yield and purity...
April 17, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
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