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https://www.readbyqxmd.com/read/28632200/the-beginning-and-development-of-the-theranostic-approach-in-nuclear-medicine-as-exemplified-by-the-radionuclide-pair-86-y-and-90-y
#1
Frank Rösch, Hans Herzog, Syed M Qaim
In the context of radiopharmacy and molecular imaging, the concept of theranostics entails a therapy-accompanying diagnosis with the aim of a patient-specific treatment. Using the adequate diagnostic radiopharmaceutical, the disease and the state of the disease are verified for an individual patient. The other way around, it verifies that the radiopharmaceutical in hand represents a target-specific and selective molecule: the "best one" for that individual patient. Transforming diagnostic imaging into quantitative dosimetric information, the optimum radioactivity (expressed in maximum radiation dose to the target tissue and tolerable dose to healthy organs) of the adequate radiotherapeutical is applied to that individual patient...
June 20, 2017: Pharmaceuticals
https://www.readbyqxmd.com/read/28631877/identification-of-chemical-components-in-baidianling-capsule-based-on-gc-ms-and-hplc-combined-with-fourier-transform-ion-cyclotron-resonance-mass-spectrometry
#2
Wenying Wu, Yu Chen, Binjie Wang, Xiaoyang Sun, Ping Guo, Xiaohui Chen
Baidianling Capsule, which is made from 16 Chinese herbs, has been widely used for treating vitiligo clinically. In this study, the sensitive and rapid method has been developed for the analysis of chemical components in Baidianling Capsule by gas chromatography with mass spectrometry in combination with retention indices and high-performance liquid chromatography combined with Fourier transform-ion cyclotron resonance mass spectrometry. Firstly, a total of 110 potential volatile compounds obtained from different extraction procedures including alkanes, alkenes, alkyne, ketones, ethers, aldehydes, alcohols, phenols, organic acids, esters, furan, pyrrole, acid amide, heterocycle and oxide were detected from Baidianling Capsule by gas chromatography with mass spectrometry, of which 75 were identified by mass spectrometry in combination with the retention index...
June 20, 2017: Journal of Separation Science
https://www.readbyqxmd.com/read/28628308/molecular-insights-into-the-transformation-of-dissolved-organic-matter-in-landfill-leachate-concentrate-during-biodegradation-and-coagulation-processes-using-esi-ft-icr-ms
#3
Ziwen Yuan, Chen He, Quan Shi, Chunming Xu, Zhenshan Li, Chengzhai Wang, Huazhang Zhao, Jinren Ni
Landfill leachate concentrate is a type of refractory organic wastewater with high environmental risk. Identification of refractory components and insights into the molecular transformations of the organics are essential for the development of efficient treatment process. In this report, molecular compositions of dissolved organic matter (DOM) in leachate concentrate, as well as changes after anaerobic/aerobic biodegradation and coagulation with salts, were characterized using electrospray ionization (ESI) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS)...
June 19, 2017: Environmental Science & Technology
https://www.readbyqxmd.com/read/28624795/tissue-and-serum-lipidome-shows-altered-lipid-composition-with-diagnostic-potential-in-mycosis-fungoides
#4
Chenchen Xu, Dan Zhou, Yixin Luo, Shuai Guo, Tao Wang, Jie Liu, Yuehua Liu, Zhili Li
Mycosis fungoides (MF) is the most common type of cutaneous T cell lymphoma. In this study, we used matrix-assisted laser desorption/ionization-Fourier transform ion cyclotron resonance mass spectrometry (MALDI-FTICR-MS) to perform lipidomic profiling of 5 MF tissue samples and 44 serum samples (22 from MF patients and 22 from control subjects). Multivariate statistical analysis of the mass spectral data showed that MF tissues had altered levels of seven lipids and MF sera had altered levels of twelve. Among these, six phosphotidylcholines, PC (34:2), PC (34:1), PC (36:3), PC (36:2), PC (32:0), and PC (38:4) and one sphingomyelin, SM (16:0) were altered in both MF tissues and sera...
May 26, 2017: Oncotarget
https://www.readbyqxmd.com/read/28621481/metal-free-room-temperature-oxygen-atom-transfer-in-the-n%C3%A2-o-co-redox-couple-as-catalyzed-by-si%C3%A2-ox-%C3%A2-x-2-5
#5
Xiaoyan Sun, Shaodong Zhou, Lei Yue, Maria Schlangen, Helmut Schwarz
The thermal reduction of N₂O by CO mediated by the metal-free cluster cations [Si₂Ox]*+ (x = 2-5) has been examined in the gas phase using Fourier transform-ion cyclotron resonance (FT-ICR) mass spectrometry in conjunction with quantum chemical calculations. Three successive oxidation/reduction steps occur starting from [Si₂O₂]*+ and N₂O to form eventually [Si₂O₅]*+; the latter as well as the intermediate oxide cluster ions react sequentially with CO molecules to regenerate [Si₂O₂]*+. Thus, full catalytic cycles occur at ambient conditions in the gas phase...
June 16, 2017: Angewandte Chemie
https://www.readbyqxmd.com/read/28611352/orbital-angular-momentum-oam-of-rotating-modes-driven-by-electrons-in-electron-cyclotron-masers
#6
Ashwini Sawant, Mun Seok Choe, Manfred Thumm, EunMi Choi
The well-defined orbital angular momentum (OAM) of rotating cavity modes operating near the cutoff frequency excited by gyrating electrons in a high-power electron cyclotron maser (ECM)-a gyrotron-has been derived by photonic and electromagnetic wave approaches. A mode generator was built with a high-precision 3D printing technique to mimic the rotating gyrotron modes for precise low-power measurements and shows clear natural production of higher-order OAM modes. Cold-test measurements of higher-order OAM mode generation promise the realization towards wireless long-range communications using high-power ECMs...
June 13, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28607428/evolution-of-complex-maillard-chemical-reactions-resolved-in-time
#7
Daniel Hemmler, Chloé Roullier-Gall, James W Marshall, Michael Rychlik, Andrew J Taylor, Philippe Schmitt-Kopplin
In this study, we monitored the thermal formation of early ribose-glycine Maillard reaction products over time by ion cyclotron resonance mass spectrometry. Here, we considered sugar decomposition (caramelization) apart from compounds that could only be produced in the presence of the amino acid. More than 300 intermediates as a result of the two initial reactants were found after ten hours (100 °C) to participate in the interplay of the Maillard reaction cascade. Despite the large numerical variety the majority of intermediates follow simple and repetitive reaction patterns...
June 12, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28599227/assessment-and-estimation-of-67-cu-production-yield-via-deuteron-induced-reactions-on-nat-zn-and-70-zn
#8
Seyedeh Fatemeh Hosseini, Mohammadreza Aboudzadeh, Mahdi Sadeghi, Ahmad Ahmadi Teymourlouy, Malihe Rostampour
(67)Cu radioisotope is a beta particle-emitting nuclide used in radioimmunotherapy (RIT) as well as for imaging, tracer kinetic studies and dosimetry. (67)Cu can be produced by bombarding (nat)Zn with deuterons. In this study, the physical yields of (67)Cu via (nat)Zn(d,x)(67)Cu reaction channel as well as via subreactions of (68)Zn(d,2pn)(67)Cu, (67)Zn(d,2p)(67)Cu, (70)Zn(d,2p3n)(67)Cu, (68)Zn(d,x)(67)Ni(T1/2=21s)→(67)Cu and (70)Zn(d,x)(67)Ni(T1/2=21s)→(67)Cu in the (nat)Zn target have been calculated by using the MCNPX-2...
May 31, 2017: Applied Radiation and Isotopes
https://www.readbyqxmd.com/read/28596540/preparation-and-in-vivo-characterization-of-51-mncl2-as-pet-tracer-of-ca-2-channel-mediated-transport
#9
Stephen A Graves, Reinier Hernandez, Hector F Valdovinos, Paul A Ellison, Jonathan W Engle, Todd E Barnhart, Weibo Cai, Robert J Nickles
Manganese has long been employed as a T1-shortening agent in magnetic resonance imaging (MRI) applications, but these techniques are limited by the biotoxicity of bulk-manganese. Positron emission tomography (PET) offers superior contrast sensitivity compared with MRI, and recent preclinical PET studies employing (52g)Mn (t1/2: 5.6 d, β(+): 29%) show promise for a variety of applications including cell tracking, neural tract tracing, immunoPET, and functional β-cell mass quantification. The half-life and confounding gamma emissions of (52g)Mn are prohibitive to clinical translation, but the short-lived (51)Mn (t1/2: 46 min, β(+): 97%) represents a viable alternative...
June 8, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28591660/the-effect-of-advanced-secondary-municipal-wastewater-treatment-on-the-molecular-composition-of-dissolved-organic-matter
#10
Andrew C Maizel, Christina K Remucal
There is a growing interest in water reuse and in recovery of nutrients from wastewater. Because many advanced treatment processes are designed to remove organic matter, a better understanding of the composition of dissolved organic matter (DOM) in wastewater is needed. To that end, we assessed DOM in the Nine Springs Wastewater Treatment Plant in Madison, Wisconsin by UV-visible spectroscopy and Fourier transform-ion cyclotron resonance mass spectrometry. Samples were collected from the influent and effluent of two different secondary treatment processes and their respective secondary clarifiers, the UV disinfection unit, and an Ostara treatment system, which produces struvite via chemical precipitation...
May 26, 2017: Water Research
https://www.readbyqxmd.com/read/28589488/negative-electron-transfer-dissociation-sequencing-of-increasingly-sulfated-glycosaminoglycan-oligosaccharides-on-an-orbitrap-mass-spectrometer
#11
Franklin E Leach, Nicholas M Riley, Michael S Westphall, Joshua J Coon, I Jonathan Amster
The structural characterization of sulfated glycosaminoglycan (GAG) carbohydrates remains an important target for analytical chemists attributable to challenges introduced by the natural complexity of these mixtures and the defined need for molecular-level details to elucidate biological structure-function relationships. Tandem mass spectrometry has proven to be the most powerful technique for this purpose. Previously, electron detachment dissociation (EDD), in comparison to other methods of ion activation, has been shown to provide the largest number of useful cleavages for de novo sequencing of GAG oligosaccharides, but such experiments are restricted to Fourier transform ion cyclotron resonance mass spectrometers (FTICR-MS)...
June 6, 2017: Journal of the American Society for Mass Spectrometry
https://www.readbyqxmd.com/read/28577143/spectroscopic-and-molecular-characterization-of-humic-substances-hs-from-soils-and-sediments-in-a-watershed-comparative-study-of-hs-chemical-fractions-and-the-origins
#12
Morgane Derrien, Yun Kyung Lee, Jae-Eun Park, Penghui Li, Meilian Chen, Sang Hee Lee, Soo Hyung Lee, Jun-Bae Lee, Jin Hur
Optical properties and molecular composition of humic substances (HS) can provide valuable information on the sources and the history of the associated biogeochemical processes. In this study, many well-known spectral and molecular characteristics were examined in eight different HS samples, which were extracted from soils and sediments located in a forested watershed, via two advanced tools including fluorescence excitation emission matrix-parallel factor analysis (EEM-PARAFAC) and high-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS)...
June 2, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28574713/structure-and-dissociation-pathways-of-protonated-tetralin-1-2-3-4-tetrahydronaphthalene
#13
Martin Vala, Jos Oomens, Giel Berden
The infrared multiple-photon dissociation (IRMPD) spectrum of protonated tetralin (1,2,3,4-tetrahydronaphthalene, THN) has been recorded using an infrared free electron laser coupled to a Fourier transform ion cyclotron mass spectrometer. IR-induced fragmentation of the protonated parent [THN + H] (+), m/z 133, yielded a single fragment ion at m/z 91. No evidence for fragment ions at m/z 131 or 132 was observed, indicating that protonated THN ejects neither atomic H nor molecular H2. Comparison of the experimental spectrum with density functional calculations (B3LYP/6-311++G(d,p)) of the two possible protonated isomers identifies a preference for the position of protonation...
June 14, 2017: Journal of Physical Chemistry. A
https://www.readbyqxmd.com/read/28572640/density-controlled-quantum-hall-ferromagnetic-transition-in-a-two-dimensional-hole-system
#14
T M Lu, L A Tracy, D Laroche, S-H Huang, Y Chuang, Y-H Su, J-Y Li, C W Liu
Quantum Hall ferromagnetic transitions are typically achieved by increasing the Zeeman energy through in-situ sample rotation, while transitions in systems with pseudo-spin indices can be induced by gate control. We report here a gate-controlled quantum Hall ferromagnetic transition between two real spin states in a conventional two-dimensional system without any in-plane magnetic field. We show that the ratio of the Zeeman splitting to the cyclotron gap in a Ge two-dimensional hole system increases with decreasing density owing to inter-carrier interactions...
June 1, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28571457/ion-cyclotron-resonance-heating-icrh-systems-for-the-keda-mirror-with-axisymmetry-kmax
#15
Ming Liu, Hongshen Yi, Munan Lin, Yanpeng Wang, Peiyun Shi, Jian Zheng, Xuan Sun
In this paper, we describe the engineering work involved in constructing two ion cyclotron resonance heating (ICRH) systems for use in the Keda Mirror with AXisymmetry tandem mirror experiment. Because they offer an effective and robust heating method, ICRH systems have been widely used in a variety of plasma experiments. The goal of our system is to heat the hydrogen plasma contained in the central cell using the fundamental ion cyclotron frequency. Both systems can deliver a radiofrequency power of ∼120 kW with adjustable operating frequencies that are tuned to be slightly lower than their local ion cyclotron frequencies...
May 2017: Review of Scientific Instruments
https://www.readbyqxmd.com/read/28552305/matrix-assisted-laser-desorption-ionization-mass-spectrometric-imaging-for-the-rapid-segmental-analysis-of-methamphetamine-in-a-single-hair-using-umbelliferone-as-a-matrix
#16
Hang Wang, Ying Wang
Segmental hair analysis offers a longer period for retrospective drug detection than blood or urine. Hair is a keratinous fiber and is strongly hydrophobic. The embedding of drugs in hydrophobic hair at low concentrations makes it difficult for extraction and detection with matrix-assisted laser desorption/ionization (MALDI) coupled with mass spectrometric imaging (MSI). In this study, a single scalp hair was longitudinally cut with a cryostat section to a length of 4 mm and fixed onto a stainless steel MALDI plate...
July 4, 2017: Analytica Chimica Acta
https://www.readbyqxmd.com/read/28533812/visualization-of-zinc-dynamics-in-intact-plants-using-positron-imaging-of-commercially-available-65-zn
#17
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
https://www.readbyqxmd.com/read/28524701/helical-water-wires
#18
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
https://www.readbyqxmd.com/read/28514206/first-in-human-pet-ct-imaging-of-metastatic-neuroendocrine-neoplasms-with-cyclotron-produced-44-sc-dotatoc-a-proof-of-concept-study
#19
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
https://www.readbyqxmd.com/read/28514059/-11-c-fluoroform-a-breakthrough-for-versatile-labeling-of-pet-radiotracer-trifluoromethyl-groups-in-high-molar-activity
#20
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
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