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Sample records for nitrogen-13 labeled radiotracers

  1. Synthesis of carbon-11, fluorine-18, and nitrogen-13 labeled radiotracers for biomedical applications

    SciTech Connect

    Fowler, J.S.; Wolf, A.P.

    1981-01-01

    A number of reviews, many of them recent, have appeared on various aspects of /sup 11/C, /sup 18/F and /sup 13/N-labeled radiotracers. This monograph treats the topic principally from the standpoint of synthetic organic chemistry while keeping in perspective the necessity of integrating the organic chemistry with the design and ultimate application of the radiotracer. Where possible, recent examples from the literature of organic synthesis are introduced to suggest potentially new routes which may be applied to problems in labeling organic molecules with the short-lived positron emitters, carbon-11, fluorine-18, and nitrogen-13. The literature survey of carbon-11, fluorine-18 and nitrogen-13 labeled compounds presented are of particular value to scientists working in this field. Two appendices are also included to provide supplementary general references. A subject index concludes this volume.

  2. Short-lived positron emitter labeled radiotracers - present status

    SciTech Connect

    Fowler, J.S.; Wolf, A.P.

    1982-01-01

    The preparation of labelled compounds is important for the application of positron emission transaxial tomography (PETT) in biomedical sciences. This paper describes problems and progress in the synthesis of short-lived positron emitter (/sup 11/C, /sup 18/F, /sup 13/N) labelled tracers for PETT. Synthesis of labelled sugars, amino acids, and neurotransmitter receptors (pimozide and spiroperidol tagged with /sup 11/C) is discussed in particular. (DLC)

  3. (68) Ga-labeled Ciprofloxacin Conjugates as Radiotracers for Targeting Bacterial Infection.

    PubMed

    Satpati, Drishty; Arjun, Chanda; Krishnamohan, Repaka; Samuel, Grace; Banerjee, Sharmila

    2016-05-01

    With an aim of developing a bacteria-specific molecular imaging agent, ciprofloxacin has been modified with a propylamine spacer and linked to two common bifunctional chelators, p-SCN-Bz-DOTA and p-SCN-Bz-NOTA. The two ciprofloxacin conjugates, CP-PA-SCN-Bz-DOTA (1) and CP-PA-SCN-Bz-NOTA (2), were radiolabeled with (68)Ga in >90% radiochemical yield and were moderately stable in vitro for 4 h. The efficacy of (68)Ga-1 and (68)Ga-2 has been investigated in vitro in Staphylococcus aureus cells where bacterial binding of the radiotracers (0.9-1.0% for (68)Ga-1 and 1.6-2.3% for (68)Ga-2) could not be blocked in the presence of excess amount of unlabeled ciprofloxacin. However, uptake of radiotracers in live bacterial cells was significantly higher (p < 0.01) than that in non-viable bacterial cells. Bacterial infection targeting efficacy of (68)Ga-1 and (68)Ga-2 was tested in vivo in rats where the infected muscle-to-inflamed muscle ((68)Ga-1: 2 ± 0.2, (68)Ga-2: 3 ± 0.5) and infected muscle-to-normal muscle ratios ((68)Ga-1: 3 ± 0.4, (68)Ga-2: 6.6 ± 0.8) were found to improve at 120 min p.i. Fast blood clearance and renal excretion was observed for both the radiotracers. The two (68)Ga-labeled infection targeting radiotracers could discriminate between bacterial infection and inflammation in vivo and are worthy of further detailed investigation as infection imaging agents at the clinical level.

  4. Evaluation of 64Cu-Labeled Acridinium Cation: A PET Radiotracer Targeting Tumor Mitochondria

    PubMed Central

    Zhou, Yang; Kim, Young-Seung; Shi, Jiyun; Jacobson, Orit; Chen, Xiaoyuan; Liu, Shuang

    2011-01-01

    This report presents the synthesis and evaluations of 64Cu(DO3A-xy-ACR) (DO3A-xy-ACR = 2,6-bis(dimethylamino)-10-(4-((4,7,10-tris(carboxymethyl)-1,4,7,10-tetraazacyclododecan-1-yl)methyl)benzyl)acridin-10-ium) as a radiotracer for imaging tumors in athymic nude mice bearing U87MG glioma xenografts by PET (positron emission tomography). The biodistribution data suggested that 64Cu(DO3A-xy-ACR) was excreted mainly through the renal system with >65% of injected radioactivity being recovered from urine samples at 1 h post-injection (p.i.). The tumor uptake of 64Cu(DO3A-xy-ACR) was 1.07 ± 0.23, 1.58 ± 0.55, 2.71 ± 0.66, 3.47 ± 1.19, and 3.52 ± 1.72 %ID/g at 0.5, 1, 2, 4 and 24 h p.i., respectively. 64Cu(DO3A-xy-ACR) had very high liver uptake (31.90 ± 3.98, 24.95 ± 5.64, 15.20 ± 4.29, 14.09 ± 6.82, and 8.18 ± 1.27 %ID/g at 0.5, 1, 2, 4 and 24 h p.i., respectively) with low tumor/liver ratios. MicroPET studies showed that the tumors were clearly visualized as early as 30 min p.i. in the glioma-bearing mouse administered with 64Cu(DO3A-xy-ACR). The high liver radioactivity accumulation was also seen. 64Cu(DO3A-xy-ACR) had a relatively high metabolic stability during excretion via both renal and hepatobiliary routes; but it was completely decomposed in the liver homogenate. We explored the localization mechanism of Cu(DO3A-xy-ACR) using both U87MG human glioma and the cultured primary U87MG glioma cells. The results from the cellular staining assays showed that 64Cu(DO3A-xy-ACR) is able to localize in the mitochondria of living U87MG glioma cells due to the enhanced negative mitochondrial potential as compared to normal cells. Although 64Cu(DO3A-xy-ACR) is not an ideal PET radiotracer for tumor imaging due to its high liver uptake, the results from this study strongly suggest that 64Cu-labeled acridinium cations are indeed able to localize in the energized mitochondria of tumor cells. PMID:21413736

  5. Cyclotron production and potential clinical application of Iodine-124 labeled radiotracers

    NASA Astrophysics Data System (ADS)

    Finn, R.; Balatoni, J.; Kothari, P.; Pentlow, K.; Sheh, Y.; Lom, C.; Dahl, J.; Eckelman, W.; Plascjak, P.; Adams, H. R.; Larson, S. M.

    2001-07-01

    Positron emission tomography (PET) is a dynamic molecular imaging technique applicable to clinical research, drug development as well as clinical diagnoses. The potential for PET is derived from specificity of the radiotracers and radioligands that are synthesized to monitor the biochemical or physiological processes. Further developments will depend on an increasing availability of unique radiotracers. Iodine-124, a radionuclide that has potential for both diagnostic and therapeutic applications, possesses a half-life of 4.18 days and decays by positron emission (23.3%) and electron capture (76.7%). The preparation of this radionuclide via the 124Te(p,n)124I nuclear reaction is described as well as chemistry associated with the preparation of specific radiotracers and radiopharmaceuticals incorporating iodine-124 at Memorial Sloan-Kettering Cancer Center.

  6. Carbon-11 labeling of CP-126,998*: A radiotracer for in vivo studies of acetylcholinesterase

    SciTech Connect

    Musachio, J.L.; Flesher, J.E.; Scheffel, U.

    1996-05-01

    The study of acetylcholinesterase (AChE) via PET is of interest as reduced activity of this enzyme has been observed in Alzheimer`s disease. Our efforts to develop a radiotracer for mapping of AChE have focused on the N-benzylpiperidine benzisoxazole, CP-126,998, a highly potent (IC{sub 50}=0.48 nm) and selective inhibitor of AChE. High specific activity [C-11] CP-126,998 was synthesized (14 - 24% radiochemical yield, non-decay corrected) by treatment of the desmethyl precursor, CP-118,954, with [C-11] methyl iodide and tetrabutylammonium hydroxide in DMF. In vivo studies with [C-11] CP-126,998 in mice show that this radiotracer displays highest uptake in striatum (6.2 %ID/g), a brain region known to be rich in AChE. The (striatum-cerebellum)/cerebellar radioactivity ratio reached a maximum of 4.3 at 30 min postinjection, and this ratio decreased to 2.4 at 120 min. .Radiotracer binding was saturable in vivo by pretreatment with CP-118,954. Pretreatment of mice with diisopropylfluorophosphate (4 mg/kg i.p.), a known AChE inhibitor, significantly inhibited binding in striatum in a dose-dependent manner. Initial results suggest that [C-11] CP-126,998 may prove useful as a marker for the study of AChE in humans via PET.

  7. A 1-methyl-4-piperidinyl cytectrene carboxylate labeled by the technetium 99m, a radiotracer for rat brain acetylcholinesterase activity.

    PubMed

    Mejri, Najoua; Barhoumi, Chokri; Trabelsi, Moez; Mekni, Abdelkader; Said, Nadia Malek; Saidi, Mouldi

    2010-02-01

    Alzheimer's disease (AD) is a degenerative neurological disorder that causes progressive and irreversible loss of connections between brain cells and loss of mental functions. Clinical and postmortem studies show that the biochemical changes in brains of AD patients include decrease in acetylcholinesterase (AChE) activity. Our aim was to study AChE activity using piperidinyl ester labelled with technetium-99m. In vivo and in vitro studies demonstrated that labelled piperidinyl ester was a substrate for AChE. The hydrolytic rate of this substrate was measured and the specificity was evaluated using the inhibitor BW284c51. The rhenium analogues of the technetium-labelled substrate were used to determine the affinity constant (K(m)) and the maximum reaction velocity (V(max)) because of the high specific activity of technetium. The high hydrolytic rate and high specificity of the substrate for AChE make it suitable as an in vivo radiotracer for studying AChE activity in the brain.

  8. Preclinical Comparative Study of (68)Ga-Labeled DOTA, NOTA, and HBED-CC Chelated Radiotracers for Targeting PSMA.

    PubMed

    Ray Banerjee, Sangeeta; Chen, Zhengping; Pullambhatla, Mrudula; Lisok, Ala; Chen, Jian; Mease, Ronnie C; Pomper, Martin G

    2016-06-15

    (68)Ga-labeled, low-molecular-weight imaging agents that target the prostate-specific membrane antigen (PSMA) are increasingly used clinically to detect prostate and other cancers with positron emission tomography (PET). The goal of this study was to compare the pharmacokinetics of three PSMA-targeted radiotracers: (68)Ga-1, using DOTA-monoamide as the chelating agent; (68)Ga-2, containing the macrocyclic chelating agent p-SCN-Bn-NOTA; and (68)Ga-DKFZ-PSMA-11, currently in clinical trials, which uses the acyclic chelating agent, HBED-CC. The PSMA-targeting scaffold for all three agents utilized a similar Glu-urea-Lys-linker construct. Each radiotracer enabled visualization of PSMA+ PC3 PIP tumor, kidney, and urinary bladder as early as 15 min post-injection using small animal PET/computed tomography (PET/CT). (68)Ga-2 demonstrated the fastest rate of clearance from all tissues in this series and displayed higher uptake in PSMA+ PC3 PIP tumor compared to (68)Ga-1 at 1 h post-injection. There was no significant difference in PSMA+ PC3 PIP tumor uptake for the three agents at 2 and 3 h post-injection. (68)Ga-DKFZ-PSMA-11 demonstrated the highest uptake and retention in normal tissues, including kidney, blood, spleen, and salivary glands and PSMA-negative PC3 flu tumors up to 3 h post-injection. In this preclinical evaluation (68)Ga-2 had the most advantageous characteristics for PSMA-targeted PET imaging.

  9. Affinity of nat/68Ga-Labelled Curcumin and Curcuminoid Complexes for β-Amyloid Plaques: Towards the Development of New Metal-Curcumin Based Radiotracers

    PubMed Central

    Rubagotti, Sara; Croci, Stefania; Ferrari, Erika; Iori, Michele; Capponi, Pier C.; Lorenzini, Luca; Calzà, Laura; Versari, Annibale; Asti, Mattia

    2016-01-01

    Curcumin derivatives labelled with fluorine-18 or technetium-99m have recently shown their potential as diagnostic tools for Alzheimer’s disease. Nevertheless, no study by exploiting the labelling with gallium-68 has been performed so far, in spite of its suitable properties (positron emitter, generator produced radionuclide). Herein, an evaluation of the affinity for synthetic β-amyloid fibrils and for amyloid plaques of three nat/68Ga-labelled curcumin analogues, namely curcumin curcumin (CUR), bis-dehydroxy-curcumin (bDHC) and diacetyl-curcumin (DAC), was performed. Affinity and specificity were tested in vitro on amyloid synthetic fibrils by using gallium-68 labelled compounds. Post-mortem brain cryosections from Tg2576 mice were used for the ex vivo visualization of amyloid plaques. The affinity of 68Ga(CUR)2+, 68Ga(DAC)2+, and 68Ga(bDHC)2+ for synthetic β-amyloid fibrils was moderate and their uptake could be observed in vitro. On the other hand, amyloid plaques could not be visualized on brain sections of Tg2576 mice after injection, probably due to the low stability of the complexes in vivo and of a hampered passage through the blood–brain barrier. Like curcumin, all nat/68Ga-curcuminoid complexes maintain a high affinity for β-amyloid plaques. However, structural modifications are still needed to improve their applicability as radiotracers in vivo. PMID:27608011

  10. Affinity of (nat/68)Ga-Labelled Curcumin and Curcuminoid Complexes for β-Amyloid Plaques: Towards the Development of New Metal-Curcumin Based Radiotracers.

    PubMed

    Rubagotti, Sara; Croci, Stefania; Ferrari, Erika; Iori, Michele; Capponi, Pier C; Lorenzini, Luca; Calzà, Laura; Versari, Annibale; Asti, Mattia

    2016-09-06

    Curcumin derivatives labelled with fluorine-18 or technetium-99m have recently shown their potential as diagnostic tools for Alzheimer's disease. Nevertheless, no study by exploiting the labelling with gallium-68 has been performed so far, in spite of its suitable properties (positron emitter, generator produced radionuclide). Herein, an evaluation of the affinity for synthetic β-amyloid fibrils and for amyloid plaques of three (nat/68)Ga-labelled curcumin analogues, namely curcumin curcumin (CUR), bis-dehydroxy-curcumin (bDHC) and diacetyl-curcumin (DAC), was performed. Affinity and specificity were tested in vitro on amyloid synthetic fibrils by using gallium-68 labelled compounds. Post-mortem brain cryosections from Tg2576 mice were used for the ex vivo visualization of amyloid plaques. The affinity of (68)Ga(CUR)₂⁺, (68)Ga(DAC)₂⁺, and (68)Ga(bDHC)₂⁺ for synthetic β-amyloid fibrils was moderate and their uptake could be observed in vitro. On the other hand, amyloid plaques could not be visualized on brain sections of Tg2576 mice after injection, probably due to the low stability of the complexes in vivo and of a hampered passage through the blood-brain barrier. Like curcumin, all (nat/68)Ga-curcuminoid complexes maintain a high affinity for β-amyloid plaques. However, structural modifications are still needed to improve their applicability as radiotracers in vivo.

  11. The Heritage of Radiotracers for PET

    DOE R&D Accomplishments Database

    Fowler, J. S.; Wolf, A. P.

    1988-05-01

    The history of PET research clearly demonstrates that it is advances in chemistry coupled with a detailed examination of the biochemistry of new radiotracers which has allowed the PET method to be applied to new areas of biology and medicine. Radiotracers whose regional distribution reflects glucose metabolism, neutrotransmitter activity and enzyme activity have all required the development of rapid synthetic methods for the radiotracers themselves and the characterization of their biochemical behavior. This article traces some of the advances in the production of labeled precursors and in radiotracer synthesis and evaluation which have shaped the rapidly expanding application of PET to problems in the neurosciences, in cardiology and in oncology.

  12. The heritage of radiotracers for PET

    SciTech Connect

    Fowler, J.S.; Wolf, A.P.

    1988-05-01

    The history of PET research clearly demonstrates that it is advances in chemistry coupled with a detailed examination of the biochemistry of new radiotracers which has allowed the PET method to be applied to new areas of biology and medicine. Radiotracers whose regional distribution reflects glucose metabolism, neutrotransmitter activity and enzyme activity have all required the development of rapid synthetic methods for the radiotracers themselves and the characterization of their biochemical behavior. This article traces some of the advances in the production of labeled precursors and in radiotracer synthesis and evaluation which have shaped the rapidly expanding application of PET to problems in the neurosciences, in cardiology and in oncology. 54 refs.

  13. Synthesis and characterization of (68)Ga-labeled curcumin and curcuminoid complexes as potential radiotracers for imaging of cancer and Alzheimer's disease.

    PubMed

    Asti, Mattia; Ferrari, Erika; Croci, Stefania; Atti, Giulia; Rubagotti, Sara; Iori, Michele; Capponi, Pier C; Zerbini, Alessandro; Saladini, Monica; Versari, Annibale

    2014-05-19

    Curcumin (CUR) and curcuminoids complexes labeled with fluorine-18 or technetium-99m have recently shown their potential as diagnostic tools for Alzheimer's disease. Gallium-68 is a positron-emitting, generator-produced radionuclide, and its properties can be exploited in situ in medical facilities without a cyclotron. Moreover, CUR showed a higher uptake in tumor cells compared to normal cells, suggesting potential diagnostic applications in this field. In spite of this, no studies using labeled CUR have been performed in this direction, so far. Herein, (68)Ga-labeled complexes with CUR and two curcuminoids, namely diacetyl-curcumin (DAC) and bis(dehydroxy)curcumin (bDHC), were synthesized and characterized by means of experimental and theoretical approaches. Moreover, a first evaluation of their affinity to synthetic β-amyloid fibrils and uptake by A549 lung cancer cells was performed to show the potential application of these new labeled curcuminoids in these diagnostic fields. The radiotracers were prepared by reacting (68)Ga(3+) obtained from a (68)Ge/(68)Ga generator with 1 mg/mL curcuminoids solutions. Reaction parameters (precursor amount, reaction temperature, and pH) were optimized to obtain high and reproducible radiochemical yield and purity. Stoichiometry and formation of the curcuminoid complexes were investigated by matrix-assisted laser desorption ionization time-of-flight mass spectrometry, NMR, ultraviolet-visible, and fluorescence spectroscopy on the equivalent (nat)Ga-curcuminoids (nat = natural) complexes, and their structure was computed by theoretical density functional theory calculations. The analyses evidenced that CUR, DAC, and bDHC were predominantly in the keto-enol form and attested to Ga(L)2(+) species formation. Identity of the (68)Ga(L)2(+) complexes was confirmed by coelution with the equivalent (nat)Ga(L)2(+) complexes in ultrahigh-performance liquid chromatography analyses.(68)Ga(CUR)2(+), (68)Ga(DAC)2(+), and (68)Ga(bDHC)2

  14. Synthesis, biological evaluation, and molecular dynamics (MD) simulation studies of three novel F-18 labeled and focal adhesion kinase (FAK) targeted 5-bromo pyrimidines as radiotracers for tumor.

    PubMed

    Fang, Yu; Wang, Dawei; Xu, Xingyu; Liu, Jianping; Wu, Aiqin; Li, Xiang; Xue, Qianqian; Wang, Huan; Wang, Hang; Zhang, Huabei

    2017-02-15

    Focal adhesion kinase (FAK) is considered as an attractive target for oncology. A series of F-18 labeled 5-bromo-N(2)-(4-(2-fluoro-pegylated (FPEG))-3,5-dimethoxyphenyl)-N(4)-(4-methoxyphenyl)pyrimidine-2,4-diamine derivatives were prepared and evaluated as the FAK targeted radiotracers for the early diagnoses of tumor. For the study of the FAK targeted drug molecules, this was the first attempt to develop the tumor diagnostic imaging agents on the radiopharmaceutical level. They inhibited the activity of FAK with IC50 in the range of 91.4-425.7 nM, and among which the result of the [(19)F]2 was relatively good and had a modest IC50 of 91.4 nM. The [(19)F]2 was also profiled in vitro against some other kinds of cancer-related kinases (including two kinds of non-receptor tyrosine kinase: PYK2 and JAK2, and three kinds of receptor tyrosine kinase: IGF-1R, EGFR and PDGFRβ). It displayed 25.2 folds selectivity against PYK2, 35.1 folds selectivity against EGFR, and more than 100 folds selectivity against IGF-1R, JAK2 and PDGFRβ. For the biodistribution in S180 bearing mice, the corresponding [(18)F]2 were also relatively good, with modest tumor uptake of 5.47 ± 0.19 and 5.80 ± 0.06 %ID/g at 15 and 30 min post-injection, respectively. Furthermore, its tumor/muscle, tumor/bone and tumor/blood ratio at 15 min post-injection were 3.16, 2.53 and 4.52, respectively. And its tumor/muscle, tumor/bone and tumor/blood ratio at 30 min post-injection were 3.14, 2.76 and 4.43, respectively. In addition, coronal micro-PET/CT images of a mouse bearing S180 tumor clearly confirmed that [(18)F]2 could be accumulated in tumor, especially at 30 min post-injection. Besides, for the [(18)F]2, both the biodistribution data and the micro-PET/CT imaging study showed significantly reduced uptake of the radiotracer in the tumor tissue at 30 min post-injection in mice that received PF-562,271 (one of the reported best selective FAK inhibitor which was developed by Pfitzer Inc. and

  15. Cerenkov Luminescence Imaging as a Modality to Evaluate Antibody-Based PET Radiotracers.

    PubMed

    D'Souza, Jimson W; Hensley, Harvey; Doss, Mohan; Beigarten, Charles; Torgov, Michael; Olafsen, Tove; Yu, Jian Q; Robinson, Matthew K

    2017-01-01

    Antibodies, and engineered antibody fragments, labeled with radioisotopes are being developed as radiotracers for the detection and phenotyping of diseases such as cancer. The development of antibody-based radiotracers requires extensive characterization of their in vitro and in vivo properties, including their ability to target tumors in an antigen-selective manner. In this study, we investigated the use of Cerenkov luminescence imaging (CLI) as compared with PET as a modality for evaluating the in vivo behavior of antibody-based radiotracers.

  16. Radiotracers for PETT: new developments and perspectives

    SciTech Connect

    Fowler, J.S.; Wolf, A.P.

    1983-01-01

    Radiotracer development with positron emitters has its major focus on problems in the neurosciences. Progress is reviewed for high-level isotope production and labelled precurser synthesis with the medical cyclotron. The study of regional brain glucose metabolism represented the first extension of one of the methods of neurochemical autoradiography to humans and the study of brain protein synthesis and neurotransmitter receptors followed. In a more general sense, one PETT instrumentation will provide resolution in the 5 mm range is already emerging. Research status is reviewed. 103 references. (PSB)

  17. Sulfonation of Tyrosine as a Method to Improve Biodistribution of Peptide-Based Radiotracers: Novel (18)F-Labelled Cyclic RGD Analogues.

    PubMed

    Haskali, Mohammad Baqir; Denoyer, Delphine; Noonan, Wayne; Cullinane, Carleen; Rangger, Christine; Pouliot, Normand; Haubner, Roland; Roselt, Peter D; Hicks, Rodney J; Hutton, Craig A

    2017-02-13

    The labeling of peptides with positron emitting radionuclides has long held the promise of a wide range of PET agents possessing high affinity and selectivity. Not surprisingly, controlling the biodistribution of these agents has proven to be a major challenge in their successful application. Modification of peptide hydrophilicity in order to increase renal clearance has been a common endeavor to improve overall biodistribution. Herein, we examine the effect of site-specific sulfonation of tyrosine moieties in cyclic(RGDyK) peptides as a means to enhance their hydrophilicity and improve their biodistribution. The novel sulfonated cyclic(RGDyK) peptides were conjugated directly to 4-nitrophenyl 2-[18F]fluoropropionate and the biodistribution of the radiolabeled peptides was compared with that of their non-sulfonated, clinically relevant counterparts, [18F]GalactoRGD and [18F]FPPRGD2. Site-specific sulfonation of the tyrosine residues was shown to increase hydrophilicity and improve biodistribution of the RGD peptides, despite contributing just 79 Da towards the MW, compared with 189 Da for both the 'Galacto' and mini-PEG moieties, suggesting this may be a broadly applicable approach to enhancing biodistribution of radiolabelled peptides.

  18. Development of a system for real-time measurements of metabolite transport in plants using short-lived positron-emitting radiotracers

    NASA Astrophysics Data System (ADS)

    Kiser, Matthew R.

    Over the past 200 years, the Earth's atmospheric carbon dioxide (CO 2) concentration has increased by more than 35%, and climate experts predict that CO2 levels may double by the end of this century. Understanding the mechanisms of resource management in plants is fundamental for predicting how plants will respond to the increase in atmospheric CO 2. Plant productivity sustains life on Earth and is a principal component of the planet's system that regulates atmospheric CO2 concentration. As such, one of the central goals of plant science is to understand the regulatory mechanisms of plant growth in a changing environment. Short-lived positron-emitting radiotracer techniques provide time-dependent data that are critical for developing models of metabolite transport and resource distribution in plants and their microenvironments. To better understand the effects of environmental changes on resource transport and allocation in plants, we have developed a system for real-time measurements of rnetabolite transport in plants using short-lived positron-emitting radio-tracers. This thesis project includes the design, construction, and demonstration of the capabilities of this system for performing real-time measurements of metabolite transport in plants. The short-lived radiotracer system described in this dissertation takes advantage of the combined capabilities and close proximity of two research facilities at. Duke University: the Triangle Universities Nuclear Laboratory (TUNL) and the Duke University Phytotron, which are separated by approximately 100 meters. The short-lived positron-emitting radioisotopes are generated using the 10-MV tandem Van de Graaff accelerator located in the main TUNL building, which provides the capability of producing short-lived positron-emitting isotopes such as carbon-11 (11C: 20 minute half-life), nitrogen-13 (13N; 10 minute half-life), fluorine-18 (18F; 110 minute half-life), and oxygen-15 (15O; 2 minute half-life). The radioisotopes may

  19. Use of supercritical carbon dioxide fluid as a solvent for the purification of pet radiotracers

    SciTech Connect

    Ferrieri, R.A.; Fowler, J.S.; Wolf, A.P.

    1993-12-31

    We have identified superfluid chromatography (SFC) as a promising method which could offer advantages in radiotracer purification through rapid separation, as well as, improved recovery and purity of labeled product. Using SF CO{sub 2} as the mobile phase for chromatographic separation of labeled product would eliminate the need for solvent removal from product prior to delivery.

  20. Principle component analysis for radiotracer signal separation.

    PubMed

    Kasban, H; Arafa, H; Elaraby, S M S

    2016-06-01

    Radiotracers can be used in several industrial applications by injecting the radiotracer into the industrial system and monitoring the radiation using radiation detectors for obtaining signals. These signals are analyzed to obtain indications about what is happening within the system or to determine the problems that may be present in the system. For multi-phase system analysis, more than one radiotracer is used and the result is a mixture of radiotracers signals. The problem is in such cases is how to separate these signals from each other. The paper presents a proposed method based on Principle Component Analysis (PCA) for separating mixed two radiotracer signals from each other. Two different radiotracers (Technetium-99m (Tc(99m)) and Barium-137m (Ba(137m))) were injected into a physical model for simulation of chemical reactor (PMSCR-MK2) for obtaining the radiotracer signals using radiation detectors and Data Acquisition System (DAS). The radiotracer signals are mixed and signal processing steps are performed include background correction and signal de-noising, then applying the signal separation algorithms. Three separation algorithms have been carried out; time domain based separation algorithm, Independent Component Analysis (ICA) based separation algorithm, and Principal Components Analysis (PCA) based separation algorithm. The results proved the superiority of the PCA based separation algorithm to the other based separation algorithm, and PCA based separation algorithm and the signal processing steps gives a considerable improvement of the separation process.

  1. The uses of radiotracers in the life sciences

    NASA Astrophysics Data System (ADS)

    Ruth, Thomas J.

    2009-01-01

    Radionuclides have been used to follow physical, chemical and biological processes almost from the time of their discovery. Probably the application with the biggest impact has been in the medical field where radionuclides have been incorporated into biologically active molecules and used to diagnose a wide variety of diseases and to treat many disorders. Other uses in the life sciences, in general, are related to using a radioactive isotope as marker for an existing species such as nitrogen-13 in plant studies or copper-67 to track copper catalysts in phytoplankton. This review describes in general terms these uses as well as providing the reader with the background related to the physical properties of radioactive decay, the concepts associated with the production of radionuclides using reactors or accelerators and the fundamentals of imaging radioactivity. The advances in imaging technology in recent years has had a profound impact on the use of radionuclides in positron emission tomography and the coupling of other imaging modalities to provide very precise insights into human disease. The variety of uses for radiotracers in science is almost boundless dependent only upon ones imagination.

  2. A philosophy for CNS radiotracer design.

    PubMed

    Van de Bittner, Genevieve C; Ricq, Emily L; Hooker, Jacob M

    2014-10-21

    Decades after its discovery, positron emission tomography (PET) remains the premier tool for imaging neurochemistry in living humans. Technological improvements in radiolabeling methods, camera design, and image analysis have kept PET in the forefront. In addition, the use of PET imaging has expanded because researchers have developed new radiotracers that visualize receptors, transporters, enzymes, and other molecular targets within the human brain. However, of the thousands of proteins in the central nervous system (CNS), researchers have successfully imaged fewer than 40 human proteins. To address the critical need for new radiotracers, this Account expounds on the decisions, strategies, and pitfalls of CNS radiotracer development based on our current experience in this area. We discuss the five key components of radiotracer development for human imaging: choosing a biomedical question, selection of a biological target, design of the radiotracer chemical structure, evaluation of candidate radiotracers, and analysis of preclinical imaging. It is particularly important to analyze the market of scientists or companies who might use a new radiotracer and carefully select a relevant biomedical question(s) for that audience. In the selection of a specific biological target, we emphasize how target localization and identity can constrain this process and discuss the optimal target density and affinity ratios needed for binding-based radiotracers. In addition, we discuss various PET test-retest variability requirements for monitoring changes in density, occupancy, or functionality for new radiotracers. In the synthesis of new radiotracer structures, high-throughput, modular syntheses have proved valuable, and these processes provide compounds with sites for late-stage radioisotope installation. As a result, researchers can manage the time constraints associated with the limited half-lives of isotopes. In order to evaluate brain uptake, a number of methods are available

  3. A Philosophy for CNS Radiotracer Design

    PubMed Central

    2015-01-01

    Conspectus Decades after its discovery, positron emission tomography (PET) remains the premier tool for imaging neurochemistry in living humans. Technological improvements in radiolabeling methods, camera design, and image analysis have kept PET in the forefront. In addition, the use of PET imaging has expanded because researchers have developed new radiotracers that visualize receptors, transporters, enzymes, and other molecular targets within the human brain. However, of the thousands of proteins in the central nervous system (CNS), researchers have successfully imaged fewer than 40 human proteins. To address the critical need for new radiotracers, this Account expounds on the decisions, strategies, and pitfalls of CNS radiotracer development based on our current experience in this area. We discuss the five key components of radiotracer development for human imaging: choosing a biomedical question, selection of a biological target, design of the radiotracer chemical structure, evaluation of candidate radiotracers, and analysis of preclinical imaging. It is particularly important to analyze the market of scientists or companies who might use a new radiotracer and carefully select a relevant biomedical question(s) for that audience. In the selection of a specific biological target, we emphasize how target localization and identity can constrain this process and discuss the optimal target density and affinity ratios needed for binding-based radiotracers. In addition, we discuss various PET test–retest variability requirements for monitoring changes in density, occupancy, or functionality for new radiotracers. In the synthesis of new radiotracer structures, high-throughput, modular syntheses have proved valuable, and these processes provide compounds with sites for late-stage radioisotope installation. As a result, researchers can manage the time constraints associated with the limited half-lives of isotopes. In order to evaluate brain uptake, a number of methods

  4. A philosophy for CNS radiotracer design

    DOE PAGES

    Van de Bittner, Genevieve C.; Ricq, Emily L.; Hooker, Jacob M.

    2014-10-01

    Decades after its discovery, positron emission tomography (PET) remains the premier tool for imaging neurochemistry in living humans. Technological improvements in radiolabeling methods, camera design, and image analysis have kept PET in the forefront. In addition, the use of PET imaging has expanded because researchers have developed new radiotracers that visualize receptors, transporters, enzymes, and other molecular targets within the human brain. However, of the thousands of proteins in the central nervous system (CNS), researchers have successfully imaged fewer than 40 human proteins. To address the critical need for new radiotracers, this Account expounds on the decisions, strategies, and pitfallsmore » of CNS radiotracer development based on our current experience in this area. We discuss the five key components of radiotracer development for human imaging: choosing a biomedical question, selection of a biological target, design of the radiotracer chemical structure, evaluation of candidate radiotracers, and analysis of preclinical imaging. It is particularly important to analyze the market of scientists or companies who might use a new radiotracer and carefully select a relevant biomedical question(s) for that audience. In the selection of a specific biological target, we emphasize how target localization and identity can constrain this process and discuss the optimal target density and affinity ratios needed for binding-based radiotracers. In addition, we discuss various PET test–retest variability requirements for monitoring changes in density, occupancy, or functionality for new radiotracers. In the synthesis of new radiotracer structures, high-throughput, modular syntheses have proved valuable, and these processes provide compounds with sites for late-stage radioisotope installation. As a result, researchers can manage the time constraints associated with the limited half-lives of isotopes. In order to evaluate brain uptake, a number of methods are

  5. A philosophy for CNS radiotracer design

    SciTech Connect

    Van de Bittner, Genevieve C.; Ricq, Emily L.; Hooker, Jacob M.

    2014-10-01

    Decades after its discovery, positron emission tomography (PET) remains the premier tool for imaging neurochemistry in living humans. Technological improvements in radiolabeling methods, camera design, and image analysis have kept PET in the forefront. In addition, the use of PET imaging has expanded because researchers have developed new radiotracers that visualize receptors, transporters, enzymes, and other molecular targets within the human brain. However, of the thousands of proteins in the central nervous system (CNS), researchers have successfully imaged fewer than 40 human proteins. To address the critical need for new radiotracers, this Account expounds on the decisions, strategies, and pitfalls of CNS radiotracer development based on our current experience in this area. We discuss the five key components of radiotracer development for human imaging: choosing a biomedical question, selection of a biological target, design of the radiotracer chemical structure, evaluation of candidate radiotracers, and analysis of preclinical imaging. It is particularly important to analyze the market of scientists or companies who might use a new radiotracer and carefully select a relevant biomedical question(s) for that audience. In the selection of a specific biological target, we emphasize how target localization and identity can constrain this process and discuss the optimal target density and affinity ratios needed for binding-based radiotracers. In addition, we discuss various PET test–retest variability requirements for monitoring changes in density, occupancy, or functionality for new radiotracers. In the synthesis of new radiotracer structures, high-throughput, modular syntheses have proved valuable, and these processes provide compounds with sites for late-stage radioisotope installation. As a result, researchers can manage the time constraints associated with the limited half-lives of isotopes. In order to evaluate brain uptake, a number of methods are

  6. PET Radiotracers of the Cardiovascular System.

    PubMed

    Gropler, Robert J

    2009-01-01

    Cardiovascular PET provides exquisite measurements of key aspects of the cardiovascular system and as a consequence it plays central role in cardiovascular investigation. Moreover, PET is now playing an ever increasing role in the management of the cardiac patient. Central to the success of PET is the development and use of novel radiotracers that permit measurements of key aspects of cardiovascular health such as myocardial perfusion, metabolism, and neuronal function. Moreover, the development of molecular imaging radiotracers is now permitting the interrogation of cellular and sub cellular processes. This article highlights these various radiotracers and their role in both cardiovascular research and potential clinical applications.

  7. Monoamine oxidase: Radiotracer chemistry and human studies

    DOE PAGES

    Fowler, Joanna S.; Logan, Jean; Shumay, Elena; ...

    2015-03-01

    Monoamine oxidase (MAO) oxidizes amines from both endogenous and exogenous sources thereby regulating the concentration of neurotransmitter amines such as serot onin, norepinephrine and dopamine as well as many xenobiotics. MAO inhibitor drugs are used in the treatment of Parkinson’s disease and in depression stimulating the development of radiotracer tools to probe the role of MAO in normal human biology and in disease. Over the past 30 since the first radiotracers were developed and the first PET images of MAO in humans were carried out, PET studies of brain MAO in healthy volunteers and in patients have identified different variablesmore » which have contributed to different MAO levels in brain and in peripheral organs. MAO radiotracers and PET have also been used to study the current and developing MAO inhibitor drugs including the selection of doses for clinical trials. In this article, we describe (1) the development of MAO radiotracers; (2) human studies including the relationship of brain MAO levels to genotype, personality, neurological and psychiatric disorders; (3) examples of the use of MAO radiotracers in drug research and development. We will conclude with outstanding needs to improve the radiotracers which are currently used and possible new applications.« less

  8. Monoamine oxidase: Radiotracer chemistry and human studies

    SciTech Connect

    Fowler, Joanna S.; Logan, Jean; Shumay, Elena; Alia-Klein, Nelly; Wang, Gene-Jack; Volkow, Nora D.

    2015-03-01

    Monoamine oxidase (MAO) oxidizes amines from both endogenous and exogenous sources thereby regulating the concentration of neurotransmitter amines such as serot onin, norepinephrine and dopamine as well as many xenobiotics. MAO inhibitor drugs are used in the treatment of Parkinson’s disease and in depression stimulating the development of radiotracer tools to probe the role of MAO in normal human biology and in disease. Over the past 30 since the first radiotracers were developed and the first PET images of MAO in humans were carried out, PET studies of brain MAO in healthy volunteers and in patients have identified different variables which have contributed to different MAO levels in brain and in peripheral organs. MAO radiotracers and PET have also been used to study the current and developing MAO inhibitor drugs including the selection of doses for clinical trials. In this article, we describe (1) the development of MAO radiotracers; (2) human studies including the relationship of brain MAO levels to genotype, personality, neurological and psychiatric disorders; (3) examples of the use of MAO radiotracers in drug research and development. We will conclude with outstanding needs to improve the radiotracers which are currently used and possible new applications.

  9. Radiotracer imaging of dopaminergic transmission in neuropsychiatric disorders.

    PubMed

    Verhoeff, N P

    1999-12-01

    This article will review the capabilities and accomplishments of radiotracer imaging with single photon emission computed tomography (SPECT) and positron emission tomography (PET) to measure pre-, post-, and "intra-synaptic" aspects of dopaminergic (DAergic) neurotransmission. The presynaptic site can be labeled with probes for the dopamine transporter (DAT) or the synthetic enzyme aromatic L-amino acid decarboxylase ("dopa decarboxylase"). The postsynaptic sites can be labeled with probes for either the dopamine D1 receptor (D1R) or the dopamine D2 receptor (D2R). The "synaptic" measurements are made indirectly by measurements of the interaction/displacement of receptor tracers by endogenous dopamine (DA). Agents are used which either release (e.g., amphetamine) or deplete (e.g., alpha-methyl-paratyrosine (AMPT), an inhibitor of tyrosine hydroxylase) tissue stores of DA. The application of these paradigms will be reviewed with special emphasis to neuropsychiatric diseases such as schizophrenia and idiopathic Parkinson's disease (IPD).

  10. Radiotracer investigation in a glass production unit.

    PubMed

    Pant, H J; Goswami, Sunil; Biswal, Jayashree; Samantaray, J S; Sharma, V K; Singhal, Sorabh

    2016-10-01

    A radiotracer investigation was carried out in a glass production unit in a glass industry. Lanthanum-140 as lanthanium oxide mixed with silica was used as a radiotracer to trace the molten glass in various sections of the unit. Residence time distributions of molten glass were measured and analyzed to identify the flow abnormities. The flow parameters such as breakthrough time, mean residence time, homogenization time, dead volume and flow patterns in different sections of the unit were obtained from the measured RTD data. The results of the investigation were used to improve and optimize the operation of the glass production unit.

  11. New-generation radiotracers for nAChR and NET.

    PubMed

    Ding, Yu-Shin; Fowler, Joanna

    2005-10-01

    Advances in radiotracer chemistry and instrumentation have merged to make positron emission tomography (PET) a powerful tool in the biomedical sciences. Positron emission tomography has found increased application in the study of drugs affecting the brain and whole body, including the measurement of drug pharmacokinetics (using a positron-emitter-labeled drug) and drug pharmacodynamics (using a labeled tracer). Thus, radiotracers are major scientific tools enabling investigations of molecular phenomena, which are at the heart of understanding human disease and developing effective treatments; however, there is evidently a bottleneck in translating basic research to clinical practice. In the meantime, the poor ability to predict the in vivo behavior of chemical compounds based on their log P's and affinities emphasizes the need for more knowledge in this area. In this article, we focus on the development and translation of radiotracers for PET studies of the nicotinic acetylcholine receptor (nAChR) and the norepinephrine transporter (NET), two molecular systems that urgently need such an important tool to better understand their functional significance in the living human brain.

  12. PET Cell Tracking Using 18F-FLT is Not Limited by Local Reuptake of Free Radiotracer

    PubMed Central

    MacAskill, Mark G.; Tavares, Adriana S.; Wu, Junxi; Lucatelli, Christophe; Mountford, Joanne C.; Baker, Andrew H.; Newby, David E.; Hadoke, Patrick W. F.

    2017-01-01

    Assessing the retention of cell therapies following implantation is vital and often achieved by labelling cells with 2′-[18F]-fluoro-2′-deoxy-D-glucose (18F-FDG). However, this approach is limited by local retention of cell-effluxed radiotracer. Here, in a preclinical model of critical limb ischemia, we assessed a novel method of cell tracking using 3′-deoxy-3′-L-[18F]-fluorothymidine (18F-FLT); a clinically available radiotracer which we hypothesise will result in minimal local radiotracer reuptake and allow a more accurate estimation of cell retention. Human endothelial cells (HUVECs) were incubated with 18F-FDG or 18F-FLT and cell characteristics were evaluated. Dynamic positron emission tomography (PET) images were acquired post-injection of free 18F-FDG/18F-FLT or 18F-FDG/18F-FLT-labelled HUVECs, following the surgical induction of mouse hind-limb ischemia. In vitro, radiotracer incorporation and efflux was similar with no effect on cell viability, function or proliferation under optimised conditions (5 MBq/mL, 60 min). Injection of free radiotracer demonstrated a faster clearance of 18F-FLT from the injection site vs. 18F-FDG (p ≤ 0.001), indicating local cellular uptake. Using 18F-FLT-labelling, estimation of HUVEC retention within the engraftment site 4 hr post-administration was 24.5 ± 3.2%. PET cell tracking using 18F-FLT labelling is an improved approach vs. 18F-FDG as it is not susceptible to local host cell reuptake, resulting in a more accurate estimation of cell retention. PMID:28287126

  13. Dynamic positron tomographic imaging with nitrogen-13 glutamate in patients with coronary artery disease: Comparison with nitrogen-13 ammonia and fluorine-18 fluorodeoxyglucose imaging

    SciTech Connect

    Krivokapich, J.; Barrio, J.R.; Huang, S.C.; Schelbert, H.R. )

    1990-11-01

    This study was designed to test the usefulness of nitrogen-13 (N-13) glutamate imaging with positron emission tomography in defining myocardial ischemia in humans. Seventeen patients who had undergone coronary arteriography were studied with N-13 glutamate at peak supine exercise using a bicycle ergometer, as well as with the flow tracer N-13 ammonia at peak exercise during a second similar exercise test. Six of the patients also underwent imaging with N-13 glutamate at rest before exercise testing; in the remaining 11 patients imaging with fluorine-18 (F-18) fluorodeoxyglucose was performed to assess glucose metabolism after the second exercise test. Seven patients had classic metabolism-flow mismatches consistent with ischemia (that is, decreased N-13 ammonia uptake in a region with relatively increased F-18 fluorodeoxyglucose uptake). There was no evidence of increased N-13 glutamate uptake in the ischemic mismatched regions in any of these patients. In all 17 patients, the uptake of N-13 glutamate during exercise paralleled the uptake of N-13 ammonia during exercise, suggesting that N-13 glutamate behaves as a flow tracer rather than as a metabolic marker of ischemia in humans.

  14. Radiotracers For Lipid Signaling Pathways In Biological Systems

    SciTech Connect

    Gatley, S. J.

    2016-09-26

    The primary focus of this project continues to be the development of radiotracers and radiotracer methodology for studying physiology and biochemistry. The compounds that have been labeled areacylethanolamines and acylglycerols that are, as classes, represented in both in plants and in animals. In the latter, some of these act as ligands for cannabinoid receptors and they are therefore known as endocannabinoids. Cannabinoid receptors are not found in plant genomes so that plants must contain other receptors and signaling systems that use acylethanolamines. Relatively little work has been done on that issue, though acylethanolamines do modulate plant growth and stress resistance, thus possessing obvious relevance to agriculture and energy production. Progress has been described in five peer-reviewed papers and seven meeting abstracts. Preparation of 2-acylglycerol lipid messengers in high purity. A novel enzymatic synthesis was developedthat gave pure 2-acylglycerols free of any rearrrangement to the thermodynamically more stable 1(3)-acylglycerol byproducts. The method utilized 1,3-dibutyryl-2-acylglycerol substrate ethanolysis by a resinimobilized lipase. Thus, pure radiolabeled 2-acylglycerols can now be conveniently prepared just prior to their utilization. These synthetic studies were published in the Journal of Medicinal Chemistry, 2011. Diacylglycerol lipase assay methodology. Diacylglycerol lipases (DAGLs) generate 2- acylglycerols, and are thus potential targets for disease- or growth-modifying agents, by means of reducing formation of 2-acylglycerols. A radioTLC assay of the hydrolysis of radiolabeled diglyceride substrate [1''-carbon-14]2-arachidonoyl-1-stearoyl-sn-glycerol has been implemented, and used to validate a novel, potentially highthroughput fluorescence resonance energy transfer (FRET) based assay. A number of new DAGL inhibitors that have selectivity for DAGLs were synthesized and screened. This work was very recently published in Bioorganic

  15. Development of indazolylpyrimidine derivatives as high-affine EphB4 receptor ligands and potential PET radiotracers.

    PubMed

    Ebert, Kristin; Wiemer, Jens; Caballero, Julio; Köckerling, Martin; Steinbach, Jörg; Pietzsch, Jens; Mamat, Constantin

    2015-09-01

    Due to their essential role in the pathogenesis of cancer, members of the Eph (erythropoietin-producing hepatoma cell line-A2) receptor tyrosine kinase family represent promising candidates for molecular imaging. Thus, the development and preparation of novel radiotracers for the noninvasive imaging of the EphB4 receptor via positron emission tomography (PET) is described. First in silico investigations with the indazolylpyrimidine lead compound which is known to be highly affine to EphB4 were executed to identify favorable labeling positions for an introduction of fluorine-18 to retain the affinity. Based on this, reference compounds as well as precursors were developed and labeled with carbon-11 and fluorine-18, respectively. For this purpose, a protecting group strategy essentially had to be generated to prevent unwanted methylation and to enable the introduction of fluorine-18. Further, a convenient radiolabeling strategy using [(11)C]methyl iodide was established which afforded the isotopically labeled radiotracer in 30-35% RCY (d.c.) which is identical with the original inhibitor molecule. A spiro ammonium precursor was prepared for radiolabeling with fluorine-18. Unfortunately, the labeling did not lead to the desired (18)F-radiotracer under the chosen conditions.

  16. Optical imaging of Cerenkov light generation from positron-emitting radiotracers

    PubMed Central

    Robertson, R; Germanos, M S; Li, C; Mitchell, G S; Cherry, S R; Silva, M D

    2009-01-01

    Radiotracers labeled with high-energy positron-emitters, such as those commonly used for positron emission tomography (PET) studies, emit visible light immediately following decay in a medium. This phenomenon, not previously described for these imaging tracers, is consistent with Cerenkov radiation and has several potential applications, especially for in vivo molecular imaging studies. Herein we detail a new molecular imaging tool, Cerenkov Luminescence Imaging, the experiments conducted that support our interpretation of the source of the signal, and proof-of-concept in vivo studies that set the foundation for future application of this new method. PMID:19636082

  17. Investigation of flow behaviour of coal particles in a pilot-scale fluidized bed gasifier (FBG) using radiotracer technique.

    PubMed

    Pant, H J; Sharma, V K; Kamudu, M Vidya; Prakash, S G; Krishanamoorthy, S; Anandam, G; Rao, P Seshubabu; Ramani, N V S; Singh, Gursharan; Sonde, R R

    2009-09-01

    Knowledge of residence time distribution (RTD), mean residence time (MRT) and degree of axial mixing of solid phase is required for efficient operation of coal gasification process. Radiotracer technique was used to measure the RTD of coal particles in a pilot-scale fluidized bed gasifier (FBG). Two different radiotracers i.e. lanthanum-140 and gold-198 labeled coal particles (100 gm) were independently used as radiotracers. The radiotracer was instantaneously injected into the coal feed line and monitored at the ash extraction line at the bottom and gas outlet at the top of the gasifier using collimated scintillation detectors. The measured RTD data were treated and MRTs of coal/ash particles were determined. The treated data were simulated using tanks-in-series model. The simulation of RTD data indicated good degree of mixing with small fraction of the feed material bypassing/short-circuiting from the bottom of the gasifier. The results of the investigation were found useful for optimizing the design and operation of the FBG, and scale-up of the gasification process.

  18. Reactions of recoil nitrogen-13 atoms in the ethanol-water system. Formation of [{sup 13}N]NH{sub 3} upon irradiation of water and dilute aqueous solutions of ethanol under a pressure of various gases

    SciTech Connect

    Korsakov, M.V.; Krasikova, R.N.; Fedorova, O.S.

    1995-07-01

    The influence of the nature and pressure of a gas (helium, hydrogen) contacting with a solution on radiochemical yield of the {sup 13}N-labeled products of nuclear-chemical and radiolytic reactions occurring upon irradiation of water and dilute aqueous solution of ethanol by 17-MeV protons was examined. It was shown that irradiation of water under hydrogen pressure, about 50% of recoil nitrogen-13 atoms are stabilized in the gas phase in the form of [{sup 13}N]N{sub 2}, and the main product in the liquid phase is ammonia-{sup 13}N.

  19. Radiotracer Technology in Mixing Processes for Industrial Applications

    PubMed Central

    Othman, N.; Kamarudin, S. K.

    2014-01-01

    Many problems associated with the mixing process remain unsolved and result in poor mixing performance. The residence time distribution (RTD) and the mixing time are the most important parameters that determine the homogenisation that is achieved in the mixing vessel and are discussed in detail in this paper. In addition, this paper reviews the current problems associated with conventional tracers, mathematical models, and computational fluid dynamics simulations involved in radiotracer experiments and hybrid of radiotracer. PMID:24616642

  20. Characterization of fast-decaying PET radiotracers solely through LC-MS/MS of constituent radioactive and carrier isotopologues

    PubMed Central

    2013-01-01

    Background The characterization of fast-decaying radiotracers that are labeled with carbon-11 (t1/2 = 20.38 min), including critical measurement of specific radioactivity (activity per mole at a specific time) before release for use in positron-emission tomography (PET), has relied heavily on chromatographic plus radiometric measurements, each of which may be vulnerable to significant errors. Thus, we aimed to develop a mass-specific detection method using sensitive liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS) for identifying 11C-labeled tracers and for verifying their specific radioactivities. Methods The LC-MS/MS was tuned and set up with methods to generate and measure the product ions specific for carbon-11 species and M + 1 carrier (predominantly the carbon-13 isotopologue) in four 11C-labeled tracers. These radiotracers were synthesized and then analyzed before extensive carbon-11 decay. The peak areas of carbon-11 species and M + 1 carrier from the LC-MS/MS measurement and the calculated abundances of carbon-12 carrier and M + 1 radioactive species gave the mole fraction of carbon-11 species in each sample. This value upon multiplication with the theoretical specific radioactivity of carbon-11 gave the specific radioactivity of the radiotracer. Results LC-MS/MS of each 11C-labeled tracer generated the product ion peaks for carbon-11 species and M + 1 carrier at the expected LC retention time. The intensity of the radioactive peak diminished as time elapsed and was undetectable after six half-lives of carbon-11. Measurements of radiotracer-specific radioactivity determined solely by LC-MS/MS at timed intervals gave a half-life for carbon-11 (20.43 min) in excellent agreement with the value obtained radiometrically. Additionally, the LC-MS/MS measurement gave specific radioactivity values (83 to 505 GBq/μmol) in good agreement with those from conventional radiometric methods. Conclusions 11C-Labeled tracers were

  1. In vivo distribution of liposome encapsulated hemoglobin studied with imaging radiotracers. Progress report

    SciTech Connect

    Phillips, W.T.

    1992-12-01

    This project has as its objective the development of radiotracer imaging technology to follow the in vivo circulation and organ deposition of liposome encapsulated hemoglobin (LEH). LEH will be labeled with technetium-99m or indium-111 and infused into small animals to monitor any in vivo differences between different LEH formulations. These studies will be correlated with any hematological and pathological changes associated with LEH treatment. Development of such non-invasive monitoring techniques may lead to significant cost effective manufacturing and formulation improvements, and ultimately a more efficacious LEH product. The development of this elegant labeling technique should make it possible to study the effect of various LEH modifications on biodistribution non-invasively in primates and humans.

  2. Demonstrating the efficacy of bioventing using radiotracers

    SciTech Connect

    Baker, R.S.; Ghaemghami, J.; Simkins, S.; Mallory, L.M.

    1994-12-31

    Direct evidence to support the effectiveness of bioventing was obtained in columns simulating unsaturated zone dynamics. Fine sandy loam from the capillary fringe of a site contaminated with toluene and xylenes was packed into glass columns. Radiolabeled [U-ring-{sup 14}C] toluene and [U-ring-{sup 14}C] m-xylene were separately added to gamma-irradiated control columns and identical nonsterile columns. Toluene (or m-xylene) and CO{sub 2} present in air drawn through the soil were continuously captured in organic vapor and NaOH traps, respectively. The addition of a radiotracer to all columns permitted an accounting of the contaminant mass balance among volatilized, biodegraded, residual, and leached fractions. During two trials involving {sup 14}C-toluene and {sup 14}C-m-xylene, 46 to 57% and 40 to 46%, respectively, of the added {sup 14}C was oxidized to {sup 14}CO{sub 2} in the nonsterile columns, demonstrating that bioremediation had been effective. Volatilization of 75% of added {sup 14}C-toluene and 54% of added {sup 14}C-m-xylene occurred in the sterile controls, whereas the nonsterile columns experienced volatile losses of less than 0.4% and 0.7%, respectively. As virtually no volatile hydrocarbons were detected in the offgas over the course of the bioventing tests from the nonsterile columns, despite the high airflow rate (15 to 20 pore volumes d{sup {minus}1}), offgas treatment may prove unnecessary during bioventing of some field sites.

  3. Designing steriod receptor-based radiotracers to image breast and prostate tumors

    SciTech Connect

    Katzenellenbogen, J.A.

    1995-06-01

    Imaging of breast or prostate cancers based on their content of steroid receptors poses a major challenge in the design of radiotracers. Receptors for steroid hormones are proteins that interact at specific sites in chromatin. Several analogs of estrogens, progestins and androgens have been radiolabeled and evaluated both in vitro and in vivo for receptor binding affinity and selectivity. Breast tumors in patients have been imaged with [{sup 18}F]fluoroestradiol. Scintigraphic images with radiolabeled progestin analogs may be useful for monitoring the efficacy of tamoxifen treatment in breast cancer patients. Tissue distribution and imaging studies in animals with fluorine-substituted androgens indicate that it may be possible to develop a steroid receptor-based radiotracer for staging prostate cancer. Radiochemists are reporting some progress in labeling steroid receptor ligands with {sup 99m}Tc. By using the techniques of molecular nuclear medicine, new imaging procedures could be developed that might provide more precise information to help characterize disease and effect treatment decisions in patients with breast or prostate cancers. 55 refs., 4 figs., 4 tabs.

  4. Optical reaction cell and light source for [18F] fluoride radiotracer synthesis

    DOEpatents

    Ferrieri, R.A.; Schlyer, D.; Becker, R.J.

    1998-09-15

    An apparatus is disclosed for performing organic synthetic reactions, particularly no-carrier-added nucleophilic radiofluorination reactions for PET radiotracer production. The apparatus includes an optical reaction cell and a source of broadband infrared radiant energy, which permits direct coupling of the emitted radiant energy with the reaction medium to heat the reaction medium. Preferably, the apparatus includes means for focusing the emitted radiant energy into the reaction cell, and the reaction cell itself is preferably configured to reflect transmitted radiant energy back into the reaction medium to further improve the efficiency of the apparatus. The apparatus is well suited to the production of high-yield syntheses of 2-[{sup 18}F]fluoro-2-deoxy-Dglucose. Also provided is a method for performing organic synthetic reactions, including the manufacture of [{sup 18}F]-labeled compounds useful as PET radiotracers, and particularly for the preparation of 2-[{sup 18}F]fluoro-2-deoxy-D-glucose in higher yields than previously possible. 4 figs.

  5. Optical reaction cell and light source for ›18F! fluoride radiotracer synthesis

    DOEpatents

    Ferrieri, Richard A.; Schlyer, David; Becker, Richard J.

    1998-09-15

    Apparatus for performing organic synthetic reactions, particularly no-carrier-added nucleophilic radiofluorination reactions for PET radiotracer production. The apparatus includes an optical reaction cell and a source of broadband infrared radiant energy, which permits direct coupling of the emitted radiant energy with the reaction medium to heat the reaction medium. Preferably, the apparatus includes means for focusing the emitted radiant energy into the reaction cell, and the reaction cell itself is preferably configured to reflect transmitted radiant energy back into the reaction medium to further improve the efficiency of the apparatus. The apparatus is well suited to the production of high-yield syntheses of 2-›.sup.18 F!fluoro-2-deoxy-D-glucose. Also provided is a method for performing organic synthetic reactions, including the manufacture of ›.sup.18 F!-labeled compounds useful as PET radiotracers, and particularly for the preparation of 2-›.sup.18 F!fluoro-2-deoxy-D-glucose in higher yields than previously possible.

  6. Radiotracers Used for the Scintigraphic Detection of Infection and Inflammation

    PubMed Central

    Tsopelas, Chris

    2015-01-01

    Over the last forty years, a small group of commercial radiopharmaceuticals have found their way into routine medical use, for the diagnostic imaging of patients with infection or inflammation. These molecular radiotracers usually participate in the immune response to an antigen, by tagging leukocytes or other molecules/cells that are endogenous to the process. Currently there is an advancing effort by researchers in the preclinical domain to design and develop new agents for this application. This review discusses radiopharmaceuticals used in the nuclear medicine clinic today, as well as those potential radiotracers that exploit an organism's defence mechanisms to an infectious or inflammatory event. PMID:25741532

  7. The Production of Radionuclides for Radiotracers in Nuclear Medicine

    NASA Astrophysics Data System (ADS)

    Ruth, Thomas J.

    Medical applications represent the vast majority of the uses for radiotracers. This review addresses how accelerators are employed for the production of high purity radionuclides that are used in basic biomedical research, as well as for clinical medicine both for diagnosing disease and for treatment.

  8. Radiotracers for Cardiac Sympathetic Innervation: Transport Kinetics and Binding Affinities for the Human Norepinephrine Transporter

    PubMed Central

    Raffel, David M.; Chen, Wei; Jung, Yong-Woon; Jang, Keun Sam; Gu, Guie; Cozzi, Nicholas V.

    2013-01-01

    Introduction Most radiotracers for imaging of cardiac sympathetic innervation are substrates of the norepinephrine transporter (NET). The goal of this study was to characterize the NET transport kinetics and binding affinities of several sympathetic nerve radiotracers, including [11C]-(−)-meta-hydroxyephedrine, [11C]-(−)-epinephrine, and a series of [11C]-labeled phenethylguanidines under development in our laboratory. For comparison, the NET transport kinetics and binding affinities of some [3H]-labeled biogenic amines were also determined. Methods Transport kinetics studies were performed using rat C6 glioma cells stably transfected with the human norepinephrine transporter (C6-hNET cells). For each radiolabeled NET substrate, saturation transport assays with C6-hNET cells measured the Michaelis-Menten transport constants Km and Vmax for NET transport. Competitive inhibition binding assays with homogenized C6-hNET cells and [3H]mazindol provided estimates of binding affinities (KI) for NET. Results Km, Vmax and KI values were determined for each NET substrate with a high degree of reproducibility. Interestingly, C6-hNET transport rates for ‘tracer concentrations’ of substrate, given by the ratio Vmax/Km, were found to be highly correlated with neuronal transport rates measured previously in isolated rat hearts (r2 = 0.96). This suggests that the transport constants Km and Vmax measured using the C6-hNET cells accurately reflect in vivo transport kinetics. Conclusion The results of these studies show how structural changes in NET substrates influence NET binding and transport constants, providing valuable insights that can be used in the design of new tracers with more optimal kinetics for quantifying regional sympathetic nerve density. PMID:23306137

  9. Radiotracers based on technetium-94m.

    PubMed

    Gagnon, Katherine; McQuarrie, Steve; Abrams, Doug; McEwan, Alexander J; Wuest, Frank

    2011-04-01

    This review gives a survey on the use and applications of technetium-94m ((94m)Tc) as a non-conventional positron emission tomography (PET) radionuclide for molecular imaging. The first part of this review describes the production and processing of (94m)Tc. The second part covers basic concepts of technetium coordination chemistry with a special focus on the synthesis of (94m)Tc-labeled compounds for molecular imaging purposes. The review concludes with a summary and an outlook on the prospects of using (94m)Tc in the field of PET chemistry and molecular imaging.

  10. Optimization of integrated impeller mixer via radiotracer experiments.

    PubMed

    Othman, N; Kamarudin, S K; Takriff, M S; Rosli, M I; Engku Chik, E M F; Adnan, M A K

    2014-01-01

    Radiotracer experiments are carried out in order to determine the mean residence time (MRT) as well as percentage of dead zone, V dead (%), in an integrated mixer consisting of Rushton and pitched blade turbine (PBT). Conventionally, optimization was performed by varying one parameter and others were held constant (OFAT) which lead to enormous number of experiments. Thus, in this study, a 4-factor 3-level Taguchi L9 orthogonal array was introduced to obtain an accurate optimization of mixing efficiency with minimal number of experiments. This paper describes the optimal conditions of four process parameters, namely, impeller speed, impeller clearance, type of impeller, and sampling time, in obtaining MRT and V dead (%) using radiotracer experiments. The optimum conditions for the experiments were 100 rpm impeller speed, 50 mm impeller clearance, Type A mixer, and 900 s sampling time to reach optimization.

  11. Optimization of Integrated Impeller Mixer via Radiotracer Experiments

    PubMed Central

    Othman, N.; Kamarudin, S. K.; Takriff, M. S.; Rosli, M. I.; Engku Chik, E. M. F.; Adnan, M. A. K.

    2014-01-01

    Radiotracer experiments are carried out in order to determine the mean residence time (MRT) as well as percentage of dead zone, Vdead (%), in an integrated mixer consisting of Rushton and pitched blade turbine (PBT). Conventionally, optimization was performed by varying one parameter and others were held constant (OFAT) which lead to enormous number of experiments. Thus, in this study, a 4-factor 3-level Taguchi L9 orthogonal array was introduced to obtain an accurate optimization of mixing efficiency with minimal number of experiments. This paper describes the optimal conditions of four process parameters, namely, impeller speed, impeller clearance, type of impeller, and sampling time, in obtaining MRT and Vdead (%) using radiotracer experiments. The optimum conditions for the experiments were 100 rpm impeller speed, 50 mm impeller clearance, Type A mixer, and 900 s sampling time to reach optimization. PMID:24741344

  12. Radiotracer Dilution Method for Mercury Inventory Study in Electrolytic Cells

    SciTech Connect

    Sugiharto; Su'ud, Zaki; Kurniadi, Rizal; Waris, Abdul; Santoso, Sigit Budi; Abidin, Zainal; Santoso, Gatot Budi

    2010-06-22

    Purpose of the experiment is to demonstrate feasibility the use of radiotracer to measure weight of mercury in electrolytic cells of soda industry. The weight of mercury in each cell of the plant is designed approximately 1700 kg. Radiotracer is prepared by mixing {sup 203}Hg radioactive mercury with 2400 g of inactive mercury in a bath. The respective precisely weighted mercury aliquots to be injected into the cells are prepared by pouring approximately 130 g of radioactive mercury taken from the bath into 13 standard vials, in accordance with the number of the cells tested. Four standard references prepared by further dilution of {+-}2 g active mercury taken from the bath to obtain the dilution factors range of 12,000 to 20,000 from which the calibration graph is constructed. The injection process is conducting by pouring the radioactive mercury from aliquots into the flowing mercury at the inlet side of the cell and allows them to mix thoroughly. It is assumed that the mass of the radiotracer injected into a closed system remains constant, at least during the period of the test. From this experiment it was observed that the mixing time is two days after injection of radioactive mercury. The inactive mercury in each electrolytic cell calculated by the radiotracer method is of the range 1351.529 kg to 1966.354 kg with maximum error (95% confidence) is 1.52 %. The accuracy of measurement of the present method is better than gravimetric one which accounts 4 % of error on average.

  13. Radionuclides, radiotracers and radiopharmaceuticals for in vivo diagnosis

    NASA Astrophysics Data System (ADS)

    Wiebe, Leonard I.

    Radioactive tracers for in vivo clinical diagnosis fall within a narrow, strictly-defined set of specifications in respect of their physical properties, chemical and biochemical characteristics, and (approved) medical applications. The type of radioactive decay and physical half-life of the radionuclide are immutable properties which, along with the demands of production and supply, limit the choice of radionuclides used in medicine to only a small fraction of those known to exist. In use, the biochemical and physiological properties of a radiotracer are dictated by the chemical form of the radionuclide. This chemical form may range from elemental, molecular or ionic, to complex compounds formed by coordinate or covalent bonding of the radionuclide to either simple organic or inorganic molecules, or complex macromolecules. Few of the radiotracers which are tested in model systems ever become radiopharmaceuticals in the strictest sense. Radionuclides, radiotracers and radiopharmaceuticals in use are reviewed. Drug legislation and regulations concerning drug manufacture, as well as hospital ethical constraints and legislation concerning unsealed sources of radiation must all be satisfied in order to translate a radiopharmaceutical from the laboratory to clinical use.

  14. Radiotracers for PET and SPECT studies of neurotransmitter systems

    SciTech Connect

    Fowler, J.S.

    1991-01-01

    The study of neurotransmitter systems is one of the major thrusts in emission tomography today. The current generation of Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT) radiotracers examines neurotransmitter properties from a number of different perspectives including their pre and post synaptic sites and the activity of the enzymes which regulate their concentration. Although the dopamine system has been the most extensively investigated, other neurotransmitter systems including the acetylcholine muscarine, serotonin, benzodiazepine, opiate, NMDA and others are also under intensive development. Enzymes involved in the synthesis and regulation of neurotransmitter concentration, for example monoamine oxidase and amino acid decarboxylase has also been probed in vivo. Medical applications range from the study of normal function and the characterization of neurotransmitter activity in neurological and psychiatric diseases and in heart disease and cancer to the study of the binding of therapeutic drugs and substances of abuse. This chapter will provide an overview of the current generation of radiotracers for PET and SPECT studies of neurotransmitter systems including radiotracer design, synthesis localization mechanisms and applications in emission tomography. 60 refs., 1 tab.

  15. Separation of analyte and matrix for the direct analysis of high-purity molybdenum-based materials by electrothermal atomic spectrometry methods—I. Radiotracer investigation of thermal extraction of impurities in a graphite cup

    NASA Astrophysics Data System (ADS)

    Dočekal, Bohumil; Krivan, Viliam; Franek, Martin

    1994-06-01

    By means of radiotracers, thermal vaporization of a number of detrimental trace elements (alkali, alkali earth and heavy metals) from metallic molybdenum powder has been studied. For this purpose, molybdenum samples labelled with appropriate radiotracers of the trace elements were prepared from a slurry of molybdenum oxide, ammonium molybdate solution and a radiotracer solution. Vaporization yields were measured after electrothermal treatment of the samples at temperatures between 1900 and 3000°C. Alkali and alkali earth elements, copper and zinc were vaporized with yields higher than 98%. Possible application of the electrothermal vaporization technique to the direct analysis of high-purity molybdenumbased materials by atomic absorption and atomic emission spectrometry is discussed.

  16. Functional investigation of bone implant viability using radiotracers in a new model of osteonecrosis

    PubMed Central

    Schiper, Luis; Faintuch, Bluma Linkowski; da Silva Badaró, Roberto José; de Oliveira, Erica Aparecida; Chavez, Victor E. Arana; Chinen, Elisangela; Faintuch, Joel

    2016-01-01

    OBJECTIVES: Conventional imaging methods are excellent for the morphological characterization of the consequences of osteonecrosis; however, only specialized techniques have been considered useful for obtaining functional information. To explore the affinity of radiotracers for severely devascularized bone, a new mouse model of isolated femur implanted in a subcutaneous abdominal pocket was devised. To maintain animal mobility and longevity, the femur was harvested from syngeneic donors. Two technetium-99m-labeled tracers targeting angiogenesis and bone matrix were selected. METHODS: Medronic acid and a homodimer peptide conjugated with RGDfK were radiolabeled with technetium-99m, and biodistribution was evaluated in Swiss mice. The grafted and control femurs were evaluated after 15, 30 and 60 days, including computed tomography (CT) and histological analysis. RESULTS: Radiolabeling achieved high (>95%) radiochemical purity. The biodistribution confirmed good blood clearance 1 hour after administration. For 99mTc-hydrazinonicotinic acid (HYNIC)-E-[c(RGDfK)2, remarkable renal excretion was observed compared to 99mTc-methylene diphosphonate (MDP), but the latter, as expected, revealed higher bone uptake. The results obtained in the control femur were equal at all time points. In the implanted femur, 99mTc-HYNIC-E-[c(RGDfK)2 uptake was highest after 15 days, consistent with early angiogenesis. Regarding 99mTc-MDP in the implant, similar uptake was documented at all time points, consistent with sustained bone viability; however, the uptake was lower than that detected in the control femur, as confirmed by histology. CONCLUSIONS: 1) Graft viability was successfully diagnosed using radiotracers in severely ischemic bone at all time points. 2) Analogously, indirect information about angiogenesis could be gathered using 999mTc-HYNIC-E-[c(RGDfK)2. 3) These techniques appear promising and warrant further studies to determine their potential clinical applications. PMID

  17. PET Radiotracers: crossing the blood-brain barrier and surviving metabolism

    PubMed Central

    Pike, Victor W.

    2009-01-01

    Radiotracers for imaging protein targets in living human brain with positron emission tomography (PET) are increasingly useful in clinical research and in drug development. Such radiotracers must fulfill many criteria, among which an ability to enter brain adequately and reversibly without contamination by troublesome radiometabolites is desirable for accurate measurement of the density of a target protein (e.g., neuroreceptor, transporter, enzyme or plaque). Candidate radiotracers may fail as a result of poor passive brain entry, rejection from brain by efflux transporters or undesirable metabolism. These issues are reviewed. Emerging PET radiotracers for measuring efflux transporter function, and new strategies for ameliorating radiotracer metabolism are discussed. A growing understanding of the molecular features affecting the brain penetration, metabolism and efflux transporter sensitivity of prospective radiotracers should ultimately lead to their more rational and efficient design, and also to their greater efficacy. PMID:19616318

  18. Fluorine-18 labeling of small molecules: the use of 18F-labeled aryl fluorides derived from no-carrier-added [18F]fluoride as labeling precursors.

    PubMed

    Wuest, F

    2007-01-01

    The favourable long-half life, the ease of production and the low energy of the emitted positron make 18F an ideal radionuclide for PET imaging. Radiochemistry of 18F basically relies on two distinctive types of reactions: nucleophilic and electrophilic reactions. All syntheses of 18F-labeled radiotracers are based on either [18F]fluoride ion or [18F]fluorine gas as simple primary labeling precursors which are obtained directly from the cyclotron. They can be applied either directly to the radiosynthesis or they can be transformed into more complex labeling precursors enabling the multi-step build-up of organic tracer molecules. The topic of this review is a survey on the application of several 18F-labeled aryl fluorides as building blocks derived from no-carrier-added (n.c.a.) [18F] fluoride to build up small monomeric PET radiotracers at high specific radioactivity by multi-step synthesis procedures.

  19. The Synthesis and Evaluations of the 68Ga-Lissamine Rhodamine B (LRB) as a New Radiotracer for Imaging Tumors by Positron Emission Tomography

    PubMed Central

    Li, Xuena; Yin, Yafu; Du, Bulin; Li, Na; Li, Yaming

    2016-01-01

    Purpose. The aim of this study is to synthesize and evaluate 68Ga-labeled Lissamine Rhodamine B (LRB) as a new radiotracer for imaging MDA-MB-231 and MCF-7 cells induced tumor mice by positron emission tomography (PET). Methods. Firstly, we performed the radio synthesis and microPET imaging of 68Ga(DOTA-LRB) in athymic nude mice bearing MDA-MB-231 and MCF-7 human breast cancer xenografts. Additionally, the evaluations of 18F-fluorodeoxyglucose (FDG), as a glucose metabolism radiotracer for imaging tumors in the same xenografts, have been conducted as a comparison. Results. The radiochemical purity of 68Ga(DOTA-LRB) was >95%. MicroPET dynamic imaging revealed that the uptake of 68Ga(DOTA-LRB) was mainly in normal organs, such as kidney, heart, liver, and brain and mainly excreted from kidney. The MDA-MB-231 and MCF-7 tumors were not clearly visible in PET images at 5, 15, 30, 40, 50, and 60 min after injection of 68Ga(DOTA-LRB). The tumor uptake values of 18F-FDG were 3.79 ± 0.57 and 1.93 ± 0.48%ID/g in MDA-MB-231 and MCF-7 tumor xenografts, respectively. Conclusions. 68Ga(DOTA-LRB) can be easily synthesized with high radiochemical purity and stability; however, it may be not an ideal PET radiotracer for imaging of MDR-positive tumors. PMID:26949707

  20. Design and evaluation of radiotracers for determination of regional cerebral blood flow with PET

    SciTech Connect

    Lambrecht, R.M.; Duncan, C.C.; Shiue, C.Y.

    1982-01-01

    The tracer kinetics of 4-Fluoro(/sup 18/F)-, 4-Bromo(/sup 82/Br)- and 4-Iodo(/sup 125/I)-antipyrine and /sup 15/O-water were compared in a cat or baboon animal model. First-pass cerebral extraction and clearance with alterations in PaCO/sub 2/ were measured for whole brain. The Renkin/Crone model was used to evaluate brain capillary permeability-surface area product for 4-/sup 18/FAP in cats. Positron-emission-tomographic measurements required development of an instrument and technique for control of the arterial concentration of the radiotracer as a ramp function, so that tracer concentration changes due to radioactive decay or altered physiological processes could be accurately described with PET. Pharmacokinetic and tissue-distribution studies in cats were used to determine dosimetry for 4-/sup 18/FAP. 4-Bromoantipyrine labeled with /sup 78/Br (t = 6.5 m) is suggested as a tracer for determination of rCBF with PET.

  1. Semi-automated lab-on-a-chip for dispensing GA-68 radiotracers

    SciTech Connect

    Weinberg, Irving

    2014-03-12

    We solved a technical problem that is hindering American progress in molecular medicine, and restricting US citizens from receiving optimal diagnostic care. Specifically, the project deals with a mother/daughter generator of positron-emitting radiotracers (Ge-68/Ga-68). These generator systems are approved in Europe but cannot be used in the USA, because of safety issues related to possible breakthrough of long-lived Ge-68 (mother) atoms. Europeans have demonstrated abilities of Ga-68-labeled radiotracers to image cancer foci with high sensitivity and specificity, and to use such methods to effectively plan therapy.The USA Food and Drug Administration (FDA) and Nuclear Regulatory Commission (NRC) have taken the position that every patient administration of Ga-68 should be preceded by an assay demonstrated that Ge-68 breakthrough is within acceptable limits. Breakthrough of parent elements is a sensitive subject at the FDA, as evidenced by the recent recall of Rb-82 generators due to inadvertent administrations of Sr-82. Commercially, there is no acceptable rapid method for assaying breakthrough of Ge-68 prior to each human administration. The gamma emissions of daughter Ga-68 have higher energies than the parent Ge-68, so that the shielding assays typically employed for Mo-99/Tc-99m generators cannot be applied to Ga-68 generators. The half-life of Ga-68 is 68 minutes, so that the standard 10-half-life delay (used to assess breakthrough in Sr-82/Rb-82 generators) cannot be applied to Ga-68 generators. As a result of the aforementioned regulatory requirements, Ga-68 generators are sold in the USA for animal use only.The American clinical community’s inability to utilize Ga-68 generators impairs abilities to treat patients domestically, and puts the USA at a disadvantage in developing exportable products. The proposed DOE project aimed to take advantage of recent technological advances developed for lab-on-a-chip (LOC) applications. Based on our experiences

  2. Preliminary study of the use of radiotracers for leak detection in industrial applications

    NASA Astrophysics Data System (ADS)

    Wetchagarun, S.; Petchrak, A.; Tippayakul, C.

    2015-05-01

    One of the most widespread uses of radiotracers in the industrial applications is the leak detection of the systems. This technique can be applied, for example, to detect leak in heat exchangers or along buried industrial pipelines. The ability to perform online investigation is one of the most important advantages of the radiotracer technique over other non-radioactive leak detection methods. In this paper, a preliminary study of the leak detection using radiotracer in the laboratory scale was presented. Br-82 was selected for this work due to its chemical property, its suitable half-life and its on-site availability. The NH4Br in the form of aqueous solution was injected into the experimental system as the radiotracer. Three NaI detectors were placed along the pipelines to measure system flow rate and to detect the leakage from the piping system. The results obtained from the radiotracer technique were compared to those measured by other methods. It is found that the flow rate obtained from the radiotracer technique agreed well with the one obtained from the flow meter. The leak rate result, however, showed discrepancy between results obtained from two different measuring methods indicating further study on leak detection was required before applying this technique in the industrial system.

  3. OpenPET: A Flexible Electronics System for Radiotracer Imaging

    PubMed Central

    Moses, W. W.; Buckley, S.; Vu, C.; Peng, Q.; Pavlov, N.; Choong, W.-S.; Wu, J.; Jackson, C.

    2011-01-01

    We present the design for OpenPET, an electronics readout system designed for prototype radiotracer imaging instruments. The critical requirements are that it has sufficient performance, channel count, channel density, and power consumption to service a complete camera, and yet be simple, flexible, and customizable enough to be used with almost any detector or camera design. An important feature of this system is that each analog input is processed independently. Each input can be configured to accept signals of either polarity as well as either differential or ground referenced signals. Each signal is digitized by a continuously sampled ADC, which is processed by an FPGA to extract pulse height information. A leading edge discriminator creates a timing edge that is “time stamped” by a TDC implemented inside the FPGA. This digital information from each channel is sent to an FPGA that services 16 analog channels, and information from multiple channels is processed by this FPGA to perform logic for crystal lookup, DOI calculation, calibration, etc. As all of this processing is controlled by firmware and software, it can be modified / customized easily. The system is open source, meaning that all technical data (specifications, schematics and board layout files, source code, and instructions) will be publicly available. PMID:21297894

  4. Radiotracer computer modeling evidence that phospho-base methylation is the main route of choline synthesis in tobacco

    SciTech Connect

    McNeil, S.D.; Nuccio, M.L.; Rhodes, D.; Shachar-Hill, Y.; Hanson, A.D.

    2000-05-01

    Among flowering plants, the synthesis of choline (Cho) from ethanolamine (EA) can potentially occur via three parallel, interconnected pathways involving methylation of free bases, phospho-bases, or phosphatidyl-bases. The authors investigated which pathways operate in tobacco (Nicotiana tabacum L.) because previous work has shown that the endogenous Cho supply limits accumulation of glycine betaine in transgenic tobacco plants engineered to convert Cho to glycine betaine. The kinetics of metabolite labeling were monitored in leaf discs supplied with [{sup 33}P]phospho-EA,[{sup 33}P]phospho-monomethylethanolamine, or [{sup 14}C]formate, and the data were subjected to computer modeling. Because partial hydrolysis of phospho-bases occurred in the apoplast, modeling of phospho-base metabolism required consideration of the re-entry of [{sup 33}P]phosphate into the network. Modeling of [{sup 14}C]formate metabolism required consideration of the labeling of the EA and methyl moieties of Cho. Results supported the following conclusions: (a) The first methylation step occurs solely at the phospho-base level; (b) the second and third methylations occur mainly (83%--92% and 65%--85%, respectively) at the phospho-base level, with the remainder occurring at the phosphatidyl-base level; and (c) free Cho originates predominantly from phosphatidylcholine rather than from phospho-Cho. This study illustrates how computer modeling of radiotracer data, in conjunction with information on chemical pool sizes, can provide a coherent, quantitative picture of fluxes within a complex metabolic network.

  5. ²⁰¹Tl⁺-labelled Prussian blue nanoparticles as contrast agents for SPECT scintigraphy.

    PubMed

    Perrier, M; Busson, M; Massasso, G; Long, J; Boudousq, V; Pouget, J-P; Peyrottes, S; Perigaud, Ch; Porredon-Guarch, C; de Lapuente, J; Borras, M; Larionova, J; Guari, Y

    2014-11-21

    Prussian blue (PB) and its analogues on the nanometric scale are exciting nano-objects that combine the advantages of molecular-based materials and nanochemistry. Herein, we demonstrate that ultra-small PB nanoparticles of 2-3 nm can be easily labelled with radioactive (201)Tl(+) to obtain new nanoprobes as radiotracers for 201-thallium-based imaging.

  6. Alternative approaches for PET radiotracer development in Alzheimer's disease: imaging beyond plaque.

    PubMed

    Holland, Jason P; Liang, Steven H; Rotstein, Benjamin H; Collier, Thomas L; Stephenson, Nickeisha A; Greguric, Ivan; Vasdev, Neil

    2014-04-01

    Alzheimer's disease (AD) and related dementias show increasing clinical prevalence, yet our understanding of the etiology and pathobiology of disease-related neurodegeneration remains limited. In this regard, noninvasive imaging with radiotracers for positron emission tomography (PET) presents a unique tool for quantifying spatial and temporal changes in characteristic biological markers of brain disease and for assessing potential drug efficacy. PET radiotracers targeting different protein markers are being developed to address questions pertaining to the molecular and/or genetic heterogeneity of AD and related dementias. For example, radiotracers including [(11) C]-PiB and [(18) F]-AV-45 (Florbetapir) are being used to measure the density of Aβ-plaques in AD patients and to interrogate the biological mechanisms of disease initiation and progression. Our focus is on the development of novel PET imaging agents, targeting proteins beyond Aβ-plaques, which can be used to investigate the broader mechanism of AD pathogenesis. Here, we present the chemical basis of various radiotracers which show promise in preclinical or clinical studies for use in evaluating the phenotypic or biochemical characteristics of AD. Radiotracers for PET imaging neuroinflammation, metal ion association with Aβ-plaques, tau protein, cholinergic and cannabinoid receptors, and enzymes including glycogen-synthase kinase-3β and monoamine oxidase B amongst others, and their connection to AD are highlighted.

  7. Evaluation of radiation dose to anthropomorphic paediatric models from positron-emitting labelled tracers

    NASA Astrophysics Data System (ADS)

    Xie, Tianwu; Zaidi, Habib

    2014-03-01

    PET uses specific molecules labelled with positron-emitting radionuclides to provide valuable biochemical and physiological information. However, the administration of radiotracers to patients exposes them to low-dose ionizing radiation, which is a concern in the paediatric population since children are at a higher cancer risk from radiation exposure than adults. Therefore, radiation dosimety calculations for commonly used positron-emitting radiotracers in the paediatric population are highly desired. We evaluate the absorbed dose and effective dose for 19 positron-emitting labelled radiotracers in anthropomorphic paediatric models including the newborn, 1-, 5-, 10- and 15-year-old male and female. This is achieved using pre-calculated S-values of positron-emitting radionuclides of UF-NCI paediatric phantoms and published biokinetic data for various radiotracers. The influence of the type of anthropomorphic model, tissue weight factors and direct human- versus mouse-derived biokinetic data on the effective dose for paediatric phantoms was also evaluated. In the case of 18F-FDG, dosimetry calculations of reference paediatric patients from various dose regimens were also calculated. Among the considered radiotracers, 18F-FBPA and 15O-water resulted in the highest and lowest effective dose in the paediatric phantoms, respectively. The ICRP 103 updated tissue-weighting factors decrease the effective dose in most cases. Substantial differences of radiation dose were observed between direct human- versus mouse-derived biokinetic data. Moreover, the effect of using voxel- versus MIRD-type models on the calculation of the effective dose was also studied. The generated database of absorbed organ dose and effective dose for various positron-emitting labelled radiotracers using new generation computational models and the new ICRP tissue-weighting factors can be used for the assessment of radiation risks to paediatric patients in clinical practice. This work also contributes

  8. PET Radiotracers for Imaging the Proliferative Status of Solid Tumors

    PubMed Central

    Mach, Robert H.; Dehdashti, Farrokh; Wheeler, Kenneth T.

    2009-01-01

    Synopsis Two different strategies have been developed for imaging the proliferative status of solid tumors with the functional imaging technique, Positron Emission Tomography (PET). The first strategy uses carbon-11 labeled thymidine and/or, more recently, fluorine-18 labeled thymidine analogs. These agents are a substrate for the enzyme thymidine kinase-1 (TK-1) and provide a pulse label of the number of cells in S phase. The second method for imaging the proliferative status of a tumor uses radiolabeled ligands that bind to the sigma-2 receptor which has a 10-fold higher density in proliferating (P) tumor cells versus quiescent (Q) tumor cells. This article compares and contrasts the two different strategies for imaging the proliferative status of solid tumors, and describes the strengths and weaknesses of each approach. PMID:20046891

  9. In Vivo Imaging of Experimental Melanoma Tumors using the Novel Radiotracer 68Ga-NODAGA-Procainamide (PCA)

    PubMed Central

    Kertész, István; Vida, András; Nagy, Gábor; Emri, Miklós; Farkas, Antal; Kis, Adrienn; Angyal, János; Dénes, Noémi; Szabó, Judit P.; Kovács, Tünde; Bai, Péter; Trencsényi, György

    2017-01-01

    Purpose: The most aggressive form of skin cancer is the malignant melanoma. Because of its high metastatic potential the early detection of primary melanoma tumors and metastases using non-invasive PET imaging determines the outcome of the disease. Previous studies have already shown that benzamide derivatives, such as procainamide (PCA) specifically bind to melanin pigment. The aim of this study was to synthesize and investigate the melanin specificity of the novel 68Ga-labeled NODAGA-PCA molecule in vitro and in vivo using PET techniques. Methods: Procainamide (PCA) was conjugated with NODAGA chelator and was labeled with Ga-68 (68Ga-NODAGA-PCA). The melanin specificity of 68Ga-NODAGA-PCA was tested in vitro, ex vivo and in vivo using melanotic B16-F10 and amelanotic Melur melanoma cell lines. By subcutaneous and intravenous injection of melanoma cells tumor-bearing mice were prepared, on which biodistribution studies and small animal PET/CT scans were performed for 68Ga-NODAGA-PCA and 18FDG tracers. Results: 68Ga-NODAGA-PCA was produced with high specific activity (14.9±3.9 GBq/µmol) and with excellent radiochemical purity (98%<), at all cases. In vitro experiments showed that 68Ga-NODAGA-PCA uptake of B16-F10 cells was significantly (p≤0.01) higher than Melur cells. Ex vivo biodistribution and in vivo PET/CT studies using subcutaneous and metastatic tumor models showed significantly (p≤0.01) higher 68Ga-NODAGA-PCA uptake in B16-F10 primary tumors and lung metastases in comparison with amelanotic Melur tumors. In experiments where 18FDG and 68Ga-NODAGA-PCA uptake of B16-F10 tumors was compared, we found that the tumor-to-muscle (T/M) and tumor-to-lung (T/L) ratios were significantly (p≤0.05 and p≤0.01) higher using 68Ga-NODAGA-PCA than the 18FDG accumulation. Conclusion: Our novel radiotracer 68Ga-NODAGA-PCA showed specific binding to the melanin producing experimental melanoma tumors. Therefore, 68Ga-NODAGA-PCA is a suitable diagnostic radiotracer for

  10. Radiotracer study of the preparation of high-purity lanthanum fluoride

    SciTech Connect

    Ewing, K.J.; Jaganathan, J.; Peitersen, L.; Aggarwal, I.D. ); Sommers, J.A.; Fahey, J.V. )

    1992-06-01

    This paper reports that the behavior of the impurities iron, cobalt, yttrium, and cerium is determined via radiotracer techniques for the preparation of high-purity lanthanum fluoride. The behavior of nickel and copper during the coprecipitation of a lanthanum nitrate solution is determined by graphite furnace atomic absorption spectrometric (GFAAS) analysis. There is no commercially available radiotracer for neodymium, a key impurity associated with absorption losses in fluoride glasses. However, the chemical behavior of neodymium and that of yttrium are very similar and, therefore, it is reasonable to assume that the behavior of yttrium throughout the processing is indicative of the behavior of neodymium. The concentrations of impurities in lanthanum nitrate, carbonate, and fluoride are estimated using the radiotracer and GFAAS data for each processing step. Results indicate that while high-purity lanthanum carbonate can be prepared, any impurities present in the lanthanum carbonate will be carried quantitatively into lanthanum fluoride upon hydrofluorination.

  11. Current status of positron emission tomography radiotracers for serotonin receptors in humans.

    PubMed

    Zimmer, Luc; Le Bars, Didier

    2013-01-01

    Serotonin (5-HT) neurotransmission plays a key modulatory role in the brain. This system is critical for pathophysiological processes and many drug treatments for brain disorders interact with its 14 subtypes of receptors. Positron emission tomography (PET) is a unique tool for the study of the living brain in translational studies from animal models to patients in neurology or psychiatry. This short review is intended to cover the current status of PET radioligands used for imaging human brain 5-HT receptors. Here, we describe the available PET radioligands for the 5-HT1A , 5-HT1B , 5-HT2A , 5-HT4 and 5-HT6 receptors. Finally, we highlight the future challenges for a functional PET imaging of serotonin receptors, including the research towards specific PET radiotracers for yet unexplored serotonin receptors, the need of radiotracers for endogenous serotonin level measurement and the contribution of agonist radiotracers for functional imaging of 5-HT neurotransmission.

  12. Design, synthesis and evaluation of [(3)H]PF-7191, a highly specific nociceptin opioid peptide (NOP) receptor radiotracer for in vivo receptor occupancy (RO) studies.

    PubMed

    Zhang, Lei; Drummond, Elena; Brodney, Michael A; Cianfrogna, Julie; Drozda, Susan E; Grimwood, Sarah; Vanase-Frawley, Michelle A; Villalobos, Anabella

    2014-11-15

    Herein we report the identification of (+)-N-(2-((1H-pyrazol-1-yl)methyl)-3-((1R,3r,5S)-6'-fluoro-8-azaspiro[bicyclo[3.2.1]octane-3,1'-isochroman]-8-yl)propyl)-N-[(3)H]-methylacetamide {[(3)H]PF-7191 [(+)-11]} as a promising radiotracer for the nociceptin opioid peptide (NOP) receptor. (+)-11 demonstrated high NOP binding affinity (Ki = 0.1 nM), excellent selectivity over other opioid receptors (>1000×) and good brain permeability in rats (C(b,u)/C(p,u) = 0.29). Subsequent characterization of [(3)H](+)-11 showed a high level of specific binding and a brain bio-distribution pattern consistent with known NOP receptor expression. Furthermore, the in vivo brain binding of [(3)H](+)-11 in rats was inhibited by a selective NOP receptor antagonist in a dose-responsive manner. This overall favorable profile indicated that [(3)H](+)-11 is a robust radiotracer for pre-clinical in vivo receptor occupancy (RO) measurements and a possible substrate for carbon-11 labeling for positron emission tomography (PET) imaging in higher species.

  13. Distributed Microprocessor Automation Network for Synthesizing Radiotracers Used in Positron Emission Tomography [PET

    DOE R&D Accomplishments Database

    Russell, J. A. G.; Alexoff, D. L.; Wolf, A. P.

    1984-09-01

    This presentation describes an evolving distributed microprocessor network for automating the routine production synthesis of radiotracers used in Positron Emission Tomography. We first present a brief overview of the PET method for measuring biological function, and then outline the general procedure for producing a radiotracer. The paper identifies several reasons for our automating the syntheses of these compounds. There is a description of the distributed microprocessor network architecture chosen and the rationale for that choice. Finally, we speculate about how this network may be exploited to extend the power of the PET method from the large university or National Laboratory to the biomedical research and clinical community at large. (DT)

  14. Synthesis and Biological Evaluation of Thiophene-Based Cannabinoid Receptor Type 2 Radiotracers for PET Imaging.

    PubMed

    Haider, Ahmed; Müller Herde, Adrienne; Slavik, Roger; Weber, Markus; Mugnaini, Claudia; Ligresti, Alessia; Schibli, Roger; Mu, Linjing; Mensah Ametamey, Simon

    2016-01-01

    Over the past two decades, our understanding of the endocannabinoid system has greatly improved due to the wealth of results obtained from exploratory studies. Currently, two cannabinoid receptor subtypes have been well-characterized. The cannabinoid receptor type 1 (CB1) is widely expressed in the central nervous system, while the levels of the cannabinoid receptor type 2 (CB2) in the brain and spinal cord of healthy individuals are relatively low. However, recent studies demonstrated a CB2 upregulation on activated microglia upon neuroinflammation, an indicator of neurodegeneration. Our research group aims to develop a suitable positron emission tomography (PET) tracer to visualize the CB2 receptor in patients suffering from neurodegenerative diseases. Herein we report two novel thiophene-based (11)C-labeled PET ligands designated [(11)C]AAT-015 and [(11)C]AAT-778. The reference compounds were synthesized using Gewald reaction conditions to obtain the aminothiophene intermediates, followed by amide formation. Saponification of the esters provided their corresponding precursors. Binding affinity studies revealed Ki-values of 3.3 ± 0.5 nM (CB2) and 1.0 ± 0.2 μM (CB1) for AAT-015. AAT-778 showed similar Ki-values of 4.3 ± 0.7 nM (CB2) and 1.1 ± 0.1 μM (CB1). Radiosynthesis was carried out under basic conditions using [(11)C]iodomethane as methylating agent. After semi-preparative HPLC purification both radiolabeled compounds were obtained in 99% radiochemical purity and the radiochemical yields ranged from 12 to 37%. Specific activity was between 96 and 449 GBq/μmol for both tracers. In order to demonstrate CB2 specificity of [(11)C]AAT-015 and [(11)C]AAT-778, we carried out autoradiography studies using CB2-positive mouse/rat spleen tissues. The obtained results revealed unspecific binding in spleen tissue that was not blocked by an excess of CB2-specific ligand GW402833. For in vivo analysis, [(11)C]AAT-015 was administered to healthy rats via tail

  15. Synthesis and Biological Evaluation of Thiophene-Based Cannabinoid Receptor Type 2 Radiotracers for PET Imaging

    PubMed Central

    Haider, Ahmed; Müller Herde, Adrienne; Slavik, Roger; Weber, Markus; Mugnaini, Claudia; Ligresti, Alessia; Schibli, Roger; Mu, Linjing; Mensah Ametamey, Simon

    2016-01-01

    Over the past two decades, our understanding of the endocannabinoid system has greatly improved due to the wealth of results obtained from exploratory studies. Currently, two cannabinoid receptor subtypes have been well-characterized. The cannabinoid receptor type 1 (CB1) is widely expressed in the central nervous system, while the levels of the cannabinoid receptor type 2 (CB2) in the brain and spinal cord of healthy individuals are relatively low. However, recent studies demonstrated a CB2 upregulation on activated microglia upon neuroinflammation, an indicator of neurodegeneration. Our research group aims to develop a suitable positron emission tomography (PET) tracer to visualize the CB2 receptor in patients suffering from neurodegenerative diseases. Herein we report two novel thiophene-based 11C-labeled PET ligands designated [11C]AAT-015 and [11C]AAT-778. The reference compounds were synthesized using Gewald reaction conditions to obtain the aminothiophene intermediates, followed by amide formation. Saponification of the esters provided their corresponding precursors. Binding affinity studies revealed Ki-values of 3.3 ± 0.5 nM (CB2) and 1.0 ± 0.2 μM (CB1) for AAT-015. AAT-778 showed similar Ki-values of 4.3 ± 0.7 nM (CB2) and 1.1 ± 0.1 μM (CB1). Radiosynthesis was carried out under basic conditions using [11C]iodomethane as methylating agent. After semi-preparative HPLC purification both radiolabeled compounds were obtained in 99% radiochemical purity and the radiochemical yields ranged from 12 to 37%. Specific activity was between 96 and 449 GBq/μmol for both tracers. In order to demonstrate CB2 specificity of [11C]AAT-015 and [11C]AAT-778, we carried out autoradiography studies using CB2-positive mouse/rat spleen tissues. The obtained results revealed unspecific binding in spleen tissue that was not blocked by an excess of CB2-specific ligand GW402833. For in vivo analysis, [11C]AAT-015 was administered to healthy rats via tail-vein injection

  16. An Investigation of the Effectiveness of Radiotracer Techniques for Instruction in Microbiology.

    ERIC Educational Resources Information Center

    Hurlburt, Evelyn McClelland

    Students in a junior college microbiology course were randomly assigned to one of two laboratory treatments: one using radiotracer techniques to investigate aspects of microbial metabolism, and the other using conventional techniques to investigate the same metabolic features. An achievement test administered at the completion of the unit and six…

  17. 18F-Labeled Silicon-Based Fluoride Acceptors: Potential Opportunities for Novel Positron Emitting Radiopharmaceuticals

    PubMed Central

    Bernard-Gauthier, Vadim; Wängler, Carmen; Wängler, Bjoern; Schirrmacher, Ralf

    2014-01-01

    Background. Over the recent years, radiopharmaceutical chemistry has experienced a wide variety of innovative pushes towards finding both novel and unconventional radiochemical methods to introduce fluorine-18 into radiotracers for positron emission tomography (PET). These “nonclassical” labeling methodologies based on silicon-, boron-, and aluminium-18F chemistry deviate from commonplace bonding of an [18F]fluorine atom (18F) to either an aliphatic or aromatic carbon atom. One method in particular, the silicon-fluoride-acceptor isotopic exchange (SiFA-IE) approach, invalidates a dogma in radiochemistry that has been widely accepted for many years: the inability to obtain radiopharmaceuticals of high specific activity (SA) via simple IE. Methodology. The most advantageous feature of IE labeling in general is that labeling precursor and labeled radiotracer are chemically identical, eliminating the need to separate the radiotracer from its precursor. SiFA-IE chemistry proceeds in dipolar aprotic solvents at room temperature and below, entirely avoiding the formation of radioactive side products during the IE. Scope of Review. A great plethora of different SiFA species have been reported in the literature ranging from small prosthetic groups and other compounds of low molecular weight to labeled peptides and most recently affibody molecules. Conclusions. The literature over the last years (from 2006 to 2014) shows unambiguously that SiFA-IE and other silicon-based fluoride acceptor strategies relying on 18F− leaving group substitutions have the potential to become a valuable addition to radiochemistry. PMID:25157357

  18. Novel methodology for the study of mercury methylation and reduction in sediments and water using 197Hg radiotracer.

    PubMed

    Ribeiro Guevara, Sergio; Zizek, Suzana; Repinc, Urska; Pérez Catán, Soledad; Jaćimović, Radojko; Horvat, Milena

    2007-03-01

    Mercury tracers are powerful tools that can be used to study mercury transformations in environmental systems, particularly mercury methylation, demethylation and reduction in sediments and water. However, mercury transformation studies using tracers can be subject to error, especially when used to assess methylation potential. The organic mercury extracted can be as low as 0.01% of the endogenous labeled mercury, and artefacts and contamination present during methylmercury (MeHg) extraction processes can cause interference. Solvent extraction methods based on the use of either KBr/H2SO4 or HCl were evaluated in freshwater sediments using 197Hg radiotracer. Values obtained for the 197Hg tracer in the organic phase were up to 25-fold higher when HCl was used, which is due to the coextraction of 197Hg2+ into the organic phase during MeHg extraction. Evaluations of the production of MeHg gave similar results with both MeHg extraction procedures, but due to the higher Hg2+ contamination of the controls, the uncertainty in the determination was higher when HCl was used. The Hg2+ contamination of controls in the HCl extraction method showed a nonlinear correlation with the humic acid content of sediment pore water. Therefore, use of the KBr/H2SO4 method is recommended, since it is free from these interferences. 197Hg radiotracer (T1/2=2.673 d) has a production rate that is about 50 times higher than that of 203Hg (T1/2=46.595 d), the most frequently used mercury radiotracer. Hence it is possible to obtain a similar level of performance to 203Hg when it is used it in short-term experiments and produced by the irradiation of 196Hg with thermal neutrons, using mercury targets with the natural isotopic composition. However, if the 0.15% natural abundance of the 196Hg isotope is increased, the specific activity of the 197Hg tracer can be significantly improved. In the present work, 197Hg tracer was produced from mercury 51.58% enriched in the 196Hg isotope, and a 340-fold

  19. Cerenkov luminescence endoscopy: Improved molecular sensitivity with β--emitting radiotracers

    DOE PAGES

    Carpenter, Colin M.; Ma, Xiaowei; Liu, Hongguang; ...

    2014-10-09

    Cerenkov luminescence endoscopy (CLE) is an optical technique that captures the Cerenkov photons emitted from highly energetic moving charged particles (β+ or β$-$) and can be used to monitor the distribution of many clinically available radioactive probes. A main limitation of CLE is its limited sensitivity to small concentrations of radiotracer, especially when used with a light guide. We investigated the improvement in the sensitivity of CLE brought about by using a β$-$ radiotracer that improved Cerenkov signal due to both higher β-particle energy and lower γ noise in the imaging optics because of the lack of positron annihilation. Here,more » the signal-to-noise ratio (SNR) of 90Y was compared with that of 18F in both phantoms and small-animal tumor models. Sensitivity and noise characteristics were demonstrated using vials of activity both at the surface and beneath 1 cm of tissue. Rodent U87MG glioma xenograft models were imaged with radiotracers bound to arginine-glycine-aspartate (RGD) peptides to determine the SNR. As a result, γ noise from 18F was demonstrated by both an observed blurring across the field of view and a more pronounced fall-off with distance. A decreased γ background and increased energy of the β particles resulted in a 207-fold improvement in the sensitivity of 90Y compared with 18F in phantoms. 90Y-bound RGD peptide produced a higher tumor-to-background SNR than 18F in a mouse model. In conclusion, the use of 90Y for Cerenkov endoscopic imaging enabled superior results compared with an 18F radiotracer.« less

  20. Cerenkov luminescence endoscopy: Improved molecular sensitivity with β--emitting radiotracers

    SciTech Connect

    Carpenter, Colin M.; Ma, Xiaowei; Liu, Hongguang; Sun, Conroy; Pratx, Guillem; Wang, Jing; Gambhir, Sanjiv S.; Xing, Lei; Cheng, Zhen

    2014-10-09

    Cerenkov luminescence endoscopy (CLE) is an optical technique that captures the Cerenkov photons emitted from highly energetic moving charged particles (β+ or β$-$) and can be used to monitor the distribution of many clinically available radioactive probes. A main limitation of CLE is its limited sensitivity to small concentrations of radiotracer, especially when used with a light guide. We investigated the improvement in the sensitivity of CLE brought about by using a β$-$ radiotracer that improved Cerenkov signal due to both higher β-particle energy and lower γ noise in the imaging optics because of the lack of positron annihilation. Here, the signal-to-noise ratio (SNR) of 90Y was compared with that of 18F in both phantoms and small-animal tumor models. Sensitivity and noise characteristics were demonstrated using vials of activity both at the surface and beneath 1 cm of tissue. Rodent U87MG glioma xenograft models were imaged with radiotracers bound to arginine-glycine-aspartate (RGD) peptides to determine the SNR. As a result, γ noise from 18F was demonstrated by both an observed blurring across the field of view and a more pronounced fall-off with distance. A decreased γ background and increased energy of the β particles resulted in a 207-fold improvement in the sensitivity of 90Y compared with 18F in phantoms. 90Y-bound RGD peptide produced a higher tumor-to-background SNR than 18F in a mouse model. In conclusion, the use of 90Y for Cerenkov endoscopic imaging enabled superior results compared with an 18F radiotracer.

  1. Residence time distribution measurements in a pilot-scale poison tank using radiotracer technique.

    PubMed

    Pant, H J; Goswami, Sunil; Samantray, J S; Sharma, V K; Maheshwari, N K

    2015-09-01

    Various types of systems are used to control the reactivity and shutting down of a nuclear reactor during emergency and routine shutdown operations. Injection of boron solution (borated water) into the core of a reactor is one of the commonly used methods during emergency operation. A pilot-scale poison tank was designed and fabricated to simulate injection of boron poison into the core of a reactor along with coolant water. In order to design a full-scale poison tank, it was desired to characterize flow of liquid from the tank. Residence time distribution (RTD) measurement and analysis was adopted to characterize the flow dynamics. Radiotracer technique was applied to measure RTD of aqueous phase in the tank using Bromine-82 as a radiotracer. RTD measurements were carried out with two different modes of operation of the tank and at different flow rates. In Mode-1, the radiotracer was instantaneously injected at the inlet and monitored at the outlet, whereas in Mode-2, the tank was filled with radiotracer and its concentration was measured at the outlet. From the measured RTD curves, mean residence times (MRTs), dead volume and fraction of liquid pumped in with time were determined. The treated RTD curves were modeled using suitable mathematical models. An axial dispersion model with high degree of backmixing was found suitable to describe flow when operated in Mode-1, whereas a tanks-in-series model with backmixing was found suitable to describe flow of the poison in the tank when operated in Mode-2. The results were utilized to scale-up and design a full-scale poison tank for a nuclear reactor.

  2. Cerenkov Luminescence Endoscopy: Improved Molecular Sensitivity with β−-Emitting Radiotracers

    PubMed Central

    Carpenter, Colin M.; Ma, Xiaowei; Liu, Hongguang; Sun, Conroy; Pratx, Guillem; Wang, Jing; Gambhir, Sanjiv S.; Xing, Lei; Cheng, Zhen

    2015-01-01

    Cerenkov luminescence endoscopy (CLE) is an optical technique that captures the Cerenkov photons emitted from highly energetic moving charged particles (β+ or β−) and can be used to monitor the distribution of many clinically available radioactive probes. A main limitation of CLE is its limited sensitivity to small concentrations of radiotracer, especially when used with a light guide. We investigated the improvement in the sensitivity of CLE brought about by using a β− radiotracer that improved Cerenkov signal due to both higher β-particle energy and lower γ noise in the imaging optics because of the lack of positron annihilation. Methods The signal-to-noise ratio (SNR) of 90Y was compared with that of 18F in both phantoms and small-animal tumor models. Sensitivity and noise characteristics were demonstrated using vials of activity both at the surface and beneath 1 cm of tissue. Rodent U87MG glioma xenograft models were imaged with radiotracers bound to arginine-glycine-aspartate (RGD) peptides to determine the SNR. Results γ noise from 18F was demonstrated by both an observed blurring across the field of view and a more pronounced fall-off with distance. A decreased γ background and increased energy of the β particles resulted in a 207-fold improvement in the sensitivity of 90Y compared with 18F in phantoms. 90Y-bound RGD peptide produced a higher tumor-to-background SNR than 18F in a mouse model. Conclusion The use of 90Y for Cerenkov endoscopic imaging enabled superior results compared with an 18F radiotracer. PMID:25300598

  3. SPECT-OPT multimodal imaging enables accurate evaluation of radiotracers for β-cell mass assessments

    PubMed Central

    Eter, Wael A.; Parween, Saba; Joosten, Lieke; Frielink, Cathelijne; Eriksson, Maria; Brom, Maarten; Ahlgren, Ulf; Gotthardt, Martin

    2016-01-01

    Single Photon Emission Computed Tomography (SPECT) has become a promising experimental approach to monitor changes in β-cell mass (BCM) during diabetes progression. SPECT imaging of pancreatic islets is most commonly cross-validated by stereological analysis of histological pancreatic sections after insulin staining. Typically, stereological methods do not accurately determine the total β-cell volume, which is inconvenient when correlating total pancreatic tracer uptake with BCM. Alternative methods are therefore warranted to cross-validate β-cell imaging using radiotracers. In this study, we introduce multimodal SPECT - optical projection tomography (OPT) imaging as an accurate approach to cross-validate radionuclide-based imaging of β-cells. Uptake of a promising radiotracer for β-cell imaging by SPECT, 111In-exendin-3, was measured by ex vivo-SPECT and cross evaluated by 3D quantitative OPT imaging as well as with histology within healthy and alloxan-treated Brown Norway rat pancreata. SPECT signal was in excellent linear correlation with OPT data as compared to histology. While histological determination of islet spatial distribution was challenging, SPECT and OPT revealed similar distribution patterns of 111In-exendin-3 and insulin positive β-cell volumes between different pancreatic lobes, both visually and quantitatively. We propose ex vivo SPECT-OPT multimodal imaging as a highly accurate strategy for validating the performance of β-cell radiotracers. PMID:27080529

  4. SPECT-OPT multimodal imaging enables accurate evaluation of radiotracers for β-cell mass assessments.

    PubMed

    Eter, Wael A; Parween, Saba; Joosten, Lieke; Frielink, Cathelijne; Eriksson, Maria; Brom, Maarten; Ahlgren, Ulf; Gotthardt, Martin

    2016-04-15

    Single Photon Emission Computed Tomography (SPECT) has become a promising experimental approach to monitor changes in β-cell mass (BCM) during diabetes progression. SPECT imaging of pancreatic islets is most commonly cross-validated by stereological analysis of histological pancreatic sections after insulin staining. Typically, stereological methods do not accurately determine the total β-cell volume, which is inconvenient when correlating total pancreatic tracer uptake with BCM. Alternative methods are therefore warranted to cross-validate β-cell imaging using radiotracers. In this study, we introduce multimodal SPECT - optical projection tomography (OPT) imaging as an accurate approach to cross-validate radionuclide-based imaging of β-cells. Uptake of a promising radiotracer for β-cell imaging by SPECT, (111)In-exendin-3, was measured by ex vivo-SPECT and cross evaluated by 3D quantitative OPT imaging as well as with histology within healthy and alloxan-treated Brown Norway rat pancreata. SPECT signal was in excellent linear correlation with OPT data as compared to histology. While histological determination of islet spatial distribution was challenging, SPECT and OPT revealed similar distribution patterns of (111)In-exendin-3 and insulin positive β-cell volumes between different pancreatic lobes, both visually and quantitatively. We propose ex vivo SPECT-OPT multimodal imaging as a highly accurate strategy for validating the performance of β-cell radiotracers.

  5. Radiolabeled Cyclic RGD Peptides as Radiotracers for Imaging Tumors and Thrombosis by SPECT

    PubMed Central

    Zhou, Yang; Chakraborty, Sudipta; Liu, Shuang

    2011-01-01

    The integrin family is a group of transmembrane glycoprotein comprised of 19 α- and 8 β-subunits that are expressed in 25 different α/β heterodimeric combinations on the cell surface. Integrins play critical roles in many physiological processes, including cell attachment, proliferation, bone remodeling, and wound healing. Integrins also contribute to pathological events such as thrombosis, atherosclerosis, tumor invasion, angiogenesis and metastasis, infection by pathogenic microorganisms, and immune dysfunction. Among 25 members of the integrin family, the αvβ3 is studied most extensively for its role of tumor growth, progression and angiogenesis. In contrast, the αIIbβ3 is expressed exclusively on platelets, facilitates the intercellular bidirectional signaling (“inside-out” and “outside-in”) and allows the aggregation of platelets during vascular injury. The αIIbβ3 plays an important role in thrombosis by its activation and binding to fibrinogen especially in arterial thrombosis due to the high blood flow rate. In the resting state, the αIIbβ3 on platelets does not bind to fibrinogen; on activation, the conformation of platelet is altered and the binding sites of αIIbβ3 are exposed for fibrinogen to crosslink platelets. Over the last two decades, integrins have been proposed as the molecular targets for diagnosis and therapy of cancer, thrombosis and other diseases. Several excellent review articles have appeared recently to cover a broad range of topics related to the integrin-targeted radiotracers and their nuclear medicine applications in tumor imaging by single photon emission computed tomography (SPECT) or a positron-emitting radionuclide for positron emission tomography (PET). This review will focus on recent developments of αvβ3-targeted radiotracers for imaging tumors and the use of αIIbβ3-targeted radiotracers for thrombosis imaging, and discuss different approaches to maximize the targeting capability of cyclic RGD peptides

  6. The Expanding Reach of Environmental Radiotracers - New Chronometers And More Sensitive Measurements

    NASA Astrophysics Data System (ADS)

    Aalseth, C.

    2015-12-01

    Radiotracers in the environment provide powerful tools for understanding environmental processes. Viewed as an age continuum, methods using shorter-lived radionuclides (<100 y) like 3H, 7Be, 85Kr, 134Cs, and 137Cs generally rely on measurements of radioactive decay in samples. Methods using longer-lived radionuclides (>1,000 y) like 10Be, 14C, 36Cl, and 81Kr generally rely on atom-counting measurements such as accelerator mass spectrometry. Significant challenges exist in the age range between 100 and 1,000 years where useful radiotracers are difficult to measure by either method and can have very low abundance. These challenges are being addressed with more sensitive measurements using both atom counting and radioactive decay, extending the reach of established radiotracers as well as adding new chronometers. Improvements in atom-counting methods will be reviewed; the practicality of using 81Kr (abundance ~5×10-13 in atmospheric krypton) for age-dating old aquifers has been established and current work focuses on improving sample utilization efficiency to allow smaller samples to be measured. Better efficiency also brings lower-abundance isotopes within reach, for example 39Ar. Improvements in radioactive decay counting will be reviewed; these take advantage of ultra-pure materials to achieve lower backgrounds and are adding new age-dating reach to the environmental science tool-set with intermediate half-life radionuclides, for example 32Si for sediment cores. These methods also improve sensitivity for established radiotracers like 3H and will allow smaller samples to be measured, allowing specific processes to be traced. For example, using 3H as an indicator of carbon cycling through organic compounds in soil systems. Progress in both atom counting and decay counting is expanding the use of 39Ar for age-dating aquifers, measuring ocean mixing, and age-dating younger glacial ice. Argon-39 is a challenging intermediate-age radiotracer (269-year half-life) with

  7. 201Tl+-labelled Prussian blue nanoparticles as contrast agents for SPECT scintigraphy

    NASA Astrophysics Data System (ADS)

    Perrier, M.; Busson, M.; Massasso, G.; Long, J.; Boudousq, V.; Pouget, J.-P.; Peyrottes, S.; Perigaud, Ch.; Porredon-Guarch, C.; de Lapuente, J.; Borras, M.; Larionova, J.; Guari, Y.

    2014-10-01

    Prussian blue (PB) and its analogues on the nanometric scale are exciting nano-objects that combine the advantages of molecular-based materials and nanochemistry. Herein, we demonstrate that ultra-small PB nanoparticles of 2-3 nm can be easily labelled with radioactive 201Tl+ to obtain new nanoprobes as radiotracers for 201-thallium-based imaging.Prussian blue (PB) and its analogues on the nanometric scale are exciting nano-objects that combine the advantages of molecular-based materials and nanochemistry. Herein, we demonstrate that ultra-small PB nanoparticles of 2-3 nm can be easily labelled with radioactive 201Tl+ to obtain new nanoprobes as radiotracers for 201-thallium-based imaging. Electronic supplementary information (ESI) available: Experimental details and procedures, toxicological data, PXRD, TEM images, kinetics and adsorption isotherms, SPECT/CT images, Tl+ captation profiles. See DOI: 10.1039/c4nr03044c

  8. Food Labeling

    MedlinePlus

    ... in the U.S. have food labels. On every food label you will see Serving size, number of servings, and number of calories per serving Information on the amount of dietary fat, cholesterol, dietary fiber, dietary sodium, carbohydrates, dietary proteins, vitamins, ...

  9. Fluorine-18 Radiochemistry, Labeling Strategies and Synthetic Routes

    PubMed Central

    2015-01-01

    Fluorine-18 is the most frequently used radioisotope in positron emission tomography (PET) radiopharmaceuticals in both clinical and preclinical research. Its physical and nuclear characteristics (97% β+ decay, 109.7 min half-life, 635 keV positron energy), along with high specific activity and ease of large scale production, make it an attractive nuclide for radiochemical labeling and molecular imaging. Versatile chemistry including nucleophilic and electrophilic substitutions allows direct or indirect introduction of 18F into molecules of interest. The significant increase in 18F radiotracers for PET imaging accentuates the need for simple and efficient 18F-labeling procedures. In this review, we will describe the current radiosynthesis routes and strategies for 18F labeling of small molecules and biomolecules. PMID:25473848

  10. Simple, rapid method for the preparation of isotopically labeled formaldehyde

    SciTech Connect

    Hooker, Jacob Matthew; Schonberger, Matthias; Schieferstein, Hanno; Fowler, Joanna S.

    2011-10-04

    Isotopically labeled formaldehyde (*C.sup..sctn.H.sub.2O) is prepared from labeled methyl iodide (*C.sup..sctn.H.sub.3I) by reaction with an oxygen nucleophile having a pendant leaving group. The mild and efficient reaction conditions result in good yields of *C.sup..sctn.H.sub.2O with little or no *C isotopic dilution. The simple, efficient production of .sup.11CH.sub.2O is described. The use of the .sup.11CH.sub.2O for the formation of positron emission tomography tracer compounds is described. The reaction can be incorporated into automated equipment available to radiochemistry laboratories. The isotopically labeled formaldehyde can be used in a variety of reactions to provide radiotracer compounds for imaging studies as well as for scintillation counting and autoradiography.

  11. Applications of Beta Particle Detection for Synthesis and Usage of Radiotracers Developed for Positron Emission Tomography

    NASA Astrophysics Data System (ADS)

    Dooraghi, Alex Abreu

    Positron Emission Tomography (PET) is a noninvasive molecular imaging tool that requires the use of a radioactive compound or radiotracer which targets a molecular pathway of interest. We have developed and employed three beta particle radiation detection systems to advance PET. Specifically, the goals of these systems are to: 1. Automate dispensing of solutions containing a positron emitting isotope. 2. Monitor radioactivity on-chip during synthesis of a positron emitting radiotracer. 3. Assay cellular uptake on-chip of a positron emitting radiotracer. Automated protocols for measuring and dispensing solutions containing radioisotopes are essential not only for providing an optimum environment for radiation workers, but also to ensure a quantitatively accurate workflow. For the first project, we describe the development and performance of a system for automated radioactivity distribution of beta particle emitting radioisotopes such as fluorine-18 (F-18). Key to the system is a radiation detector in-line with a peristaltic pump. The system demonstrates volume accuracy within 5 % for volumes of 20 muL or greater. When considering volumes of 20 muL or greater, delivered radioactivity is in agreement with the requested radioactivity as measured with the dose calibrator. The integration of the detector and pump leads to a flexible system that can accurately dispense solutions containing F-18 in radioactivity concentrations directly produced from a cyclotron (~ 0.1-1 mCi/muL), to low activity concentrations intended for preclinical mouse scans (~ 1-10 muCi/muL), and anywhere in between. Electrowetting on dielectric (EWOD) is an attractive microfluidic platform for batch synthesis of PET radiotracers. Visualization of radioisotopes on-chip is critical for synthesis optimization and technological development. For the second project, we describe the development and performance of a Cerenkov/real-time imaging system for PET radiotracer synthesis on EWOD. We also investigate

  12. Prediction of water vapor transport rates across polyvinylchloride packaging systems using a novel radiotracer method

    SciTech Connect

    Wood, R.W.; Mulski, M.J.; Kuu, W.Y. )

    1990-09-01

    A radiotracer method is used to study the transport properties of water vapor in polyvinylchloride (PVC), a plastic commonly used in the packaging of parenteral solutions. Water vapor transport across a PVC film appears to be Fickian in nature. Using the steady-state solution of Fick's second law and the permeability coefficient of water vapor across the PVC film obtained using the described method, the predicted water vapor transport rate (WVTR) for a parenteral solution packaged in PVC is in reasonable agreement with actual WVTR as determined by weight loss under precisely controlled conditions.

  13. Food Labels

    MedlinePlus

    ... the food came from, whether the food is organic, and certain health claims. So who decides what ... make that claim. Foods that are labeled "USDA organic" are required to have at least 95% organic ...

  14. Radiotracer Injection Into the Catheter Balloon: A Subtle Pitfall Which Can Be Overlooked in Direct Radionuclide Cystography.

    PubMed

    Massoudi, Toktam; Shayegani, Hamed; Sadeghi, Ramin

    2017-04-01

    We reported a 4-year-old girl with history of bilateral vesicoureteral reflux who underwent direct radionuclide cystography in our department. Radiotracer was mistakenly injected in the catheter balloon. The filling phase showed no change in the bladder volume, and the catheter balloon was apparent as an intense activity in the base of the bladder. The procedure was repeated with correct injection of the tracer into the catheter. Wrong injection of the radiotracer into the catheter balloon should always be borne in mind in similar cases.

  15. Combination of sealed source and radiotracer technique to understand malfunctioning in a chemical plant.

    PubMed

    Yelgaonkar, V N; Jayakumar, T K; Singh, Sudhir; Sharma, M K

    2009-01-01

    Pure terphthalic acid (PTA) is produced by the oxidation of paraxylene in an oxidation reactor of a PTA plant. Since the reaction is exothermic, the temperature rises above 210 degrees C. Vapours formed in the reactor are passed through a series of heat exchangers and the cooled liquid is fed back to the reactor, which flows to the reactor by gravity. In one of the heat exchangers, improper flow distribution in the inlet and outlet pipelines was suspected. Maldistribution of flow in the heat exchanger was also suspected. Gamma scanning of the pipelines and a radiotracer experiment were carried out in the heat exchanger to study the malfunctioning. A specially fabricated pipe scanner was used to scan both 24in diameter and 16in diameter pipelines. From gamma scanning of the pipelines mostly on the bends, absence of the full bore flow of the liquid was observed. Presence of vapours along with the liquid could be obstructing the liquid flow, thereby causing the malfunctioning. A radiotracer experiment was also carried out to study the flow pattern in the heat exchanger. From the experiment, mean residence time of the heat exchanger was estimated as 470s, which theoretically should be about 102s. It indicated that the flow is decelerated in the heat exchanger because of the presence of vapour lock in the tube side.

  16. Managing Lymphoma with Non-FDG Radiotracers: Current Clinical and Preclinical Applications

    PubMed Central

    Kong, Fan-Lin; Ford, Richard J.; Yang, David J.

    2013-01-01

    Nuclear medicine imaging modalities such as positron emission tomography (PET) and single-photon emission computed tomography (SPECT) have played a prominent role in lymphoma management. PET with [18F]Fluoro-2-deoxy-D-glucose (FDG) is the most commonly used tool for lymphoma imaging. However, FDG-PET has several limitations that give the false positive or false negative diagnosis of lymphoma. Therefore, development of new radiotracers with higher sensitivity, specificity, and different uptake mechanism is in great demand in the management of lymphoma. This paper reviews non-FDG radiopharmaceuticals that have been applied for PET and SPECT imaging in patients with different types of lymphoma, with attention to diagnosis, staging, therapy response assessment, and surveillance for disease relapse. In addition, we introduce three radiolabeled anti-CD20 antibodies for radioimmunotherapy, which is another important arm for lymphoma treatment and management. Finally, the relatively promising radiotracers that are currently under preclinical development are also discussed in this paper. PMID:23841079

  17. Effect of Cyclosporin A on the Uptake of D3-Selective PET Radiotracers in Rat Brain

    PubMed Central

    Tu, Zhude; Li, Shihong; Xu, Jinbin; Chu, Wenhua; Jones, Lynne A.; Luedtke, Robert R.; Mach, Robert H.

    2011-01-01

    Introduction Four benzamide analogs having a high affinity and selectivity for D3 versus D2 receptors were radiolabeled with 11C or 18F for in vivo evaluation. Methods Precursors were synthesized and the four D3 selective benzamide analogs were radiolabeled. The tissue distribution and brain uptake of the four compounds were evaluated in control rats and rats pretreated with cyclosporin A, a modulator of P-glycoprotein and an inhibitor of other ABC efflux transporters that contribute to the blood brain barrier. MicroPET imaging was carried out for [11C]6 in a control and a cyclosporin A pre-treated rat. Results All four compounds showed low brain uptake in control rats at 5 and 30 min post-injection; despite recently reported rat behavioral studies conducted on analogs 6 (WC-10) and 7 (WC-44). Following administration of cyclosporin A, increased brain uptake was observed with all four PET radiotracers at both 5 and 30 min post-i.v. injection. An increase in brain uptake following modulation/inhibition of the ABC transporters was also observed in the microPET study. Conclusions These data suggest that D3 selective conformationally-flexible benzamide analogs which contain a N-2-methoxyphenylpiperazine moiety are substrates for P-glycoprotein or other ABC transporters expressed at the blood-brain barrier, and that PET radiotracers containing this pharmacophore may display low brain uptake in rodents due to the action of these efflux transporters. PMID:21718948

  18. Development of gamma-emitting, receptor binding radiotracers for imaging the brain and pancreas

    SciTech Connect

    Reba, R.C.

    1990-01-01

    This progress report covers period from Nov. 1, 1989 to Aug. 31, 1990. The long term objective was to develop receptor-binding radiotracers for SPECT or PET imaging of CNS or peripheral nervous system. The specific chemistry aims, as understood on the basis of past findings, were: to synthesize and develop a more polar analogs of 4IQNB, possessing similar binding characteristics but eliminated more rapidly from the surrounding tissues and the target organ, to design a method of introducing a technetium chelating group onto a molecule or cholinergic agent without drastic lowering of its apparent affinity, to synthesize and develop radiotracers based on m-AChR antagonists selective for one of the subtypes of the receptor. The chemistry service aims were to prepare and characterize (R,R)- and (R,S)-4IQNB and derivatives, to provide the triazene intermediate to other investigators, and to provide ({sup 123}I)4IQNB for in vivo imaging. The biochemistry aims were to characterize the vitro and in vivo properties of novel compounds and to perform the pharmacokinetic studies. 3 refs., 5 tabs.

  19. Synthesis and bioevaluation of [18F]4-fluoro-m-hydroxyphenethylguanidine ([18F]4F-MHPG): a novel radiotracer for quantitative PET studies of cardiac sympathetic innervation

    PubMed Central

    Jang, Keun Sam; Jung, Yong-Woon; Sherman, Phillip S.; Quesada, Carole A.; Gu, Guie; Raffel, David M.

    2013-01-01

    A new cardiac sympathetic nerve imaging agent, [18F]4-fluoro-m-hydroxyphenethylguanidine ([18F]4F-MHPG), was synthesized and evaluated. The radiosynthetic intermediate [18F]4-fluoro-m-tyramine ([18F]4F-MTA) was prepared and then sequentially reacted with cyanogen bromide and NH4Br/NH4OH to afford [18F]4F-MHPG. Initial bioevaluations of [18F]4F-MHPG (biodistribution studies in rats and kinetic studies in the isolated rat heart) were similar to results previously reported for the carbon-11 labeled analog [11C]4F-MHPG. The neuronal uptake rate of [18F]4F-MHPG into the isolated rat heart was 0.68 ml/min/g wet and its retention time in sympathetic neurons was very long (T1/2 > 13 h). A PET imaging study in a nonhuman primate with [18F]4F-MHPG provided high quality images of the heart, with heart-to-blood ratios at 80–90 min after injection of 5-to-1. These initial kinetic and imaging studies of [18F]4F-MHPG suggest that this radiotracer may allow for more accurate quantification of regional cardiac sympathetic nerve density than is currently possible with existing neuronal imaging agents. PMID:23416009

  20. Pharmacokinetic evaluation of the tau PET radiotracer [18F]T807 ([18F]AV-1451) in human subjects.

    PubMed

    Wooten, Dustin; Guehl, Nicolas J; Verwer, Eline E; Shoup, Timothy M; Yokell, Daniel L; Zubcevik, Nevena; Vasdev, Neil; Zafonte, Ross D; Johnson, Keith A; El Fakhri, Georges; Normandin, Marc David

    2016-09-22

    [(18)F]T807 is a PET radiotracer developed for imaging tau protein aggregates, which are implicated in neurological disorders including Alzheimer's disease (AD) and traumatic brain injury (TBI). The current study characterizes [(18)F]T807 pharmacokinetics in human subjects using dynamic PET imaging and metabolite-corrected arterial input functions.

  1. Flow Rate Measurement Using {sup 99m}Tc Radiotracer Method in a Pipe Installation

    SciTech Connect

    Sipaun, S. M.; Bakar, A. Q. Abu; Othman, N.; Shaari, M. R.; Adnan, M. A. K.; Yusof, J. Mohd; Demanah, R.

    2010-07-07

    Flow rate is a significant parameter for managing processes in chemical processing plants and water processing facility. Accurate measurement of the flow rate allows engineers to monitor the delivery of process material, which in turn impacts a plant's capacity to produce their products. One of the available methods for determining the flow rate of a process material is by introducing a radiotracer to the system that mimics the material's flow pattern. In this study, a low activity Technetium-99m radioisotope was injected into a water piping setup and the 2'' x 2'' NaI (Tl) detectors were calibrated to detect spectrum peaks at specific points of the pipe installation. Using pulse velocity method, water flow rate was determined to be 11.3 litres per minute. For the sampling method, at different pump capacity, the flow rate was 15.0 litres per minute.

  2. Experimental observation of silver and gold penetration into dental ceramic by means of a radiotracer technique

    SciTech Connect

    Moya, F.; Payan, J.; Bernardini, J.; Moya, E.G.

    1987-12-01

    A radiotracer technique was used to study silver and gold diffusion into dental porcelain under experimental conditions close to the real conditions in prosthetic laboratories for porcelain bakes. It was clearly shown that these non-oxidizable elements were able to diffuse into the ceramic as well as oxidizable ones. The penetration depth varied widely according to the element. The ratio DAg/DAu was about 10(3) around 850 degrees C. In contrast to gold, the silver diffusion rate was high enough to allow silver, from the metallic alloy, to be present at the external ceramic surface after diffusion into the ceramic. Hence, the greening of dental porcelains baked on silver-rich alloys could be explained mainly by a solid-state diffusion mechanism.

  3. Predicting Future Morphological Changes of Lesions from Radiotracer Uptake in 18F-FDG-PET Images

    PubMed Central

    Bagci, Ulas; Yao, Jianhua; Miller-Jaster, Kirsten; Chen, Xinjian; Mollura, Daniel J.

    2013-01-01

    We introduce a novel computational framework to enable automated identification of texture and shape features of lesions on 18F-FDG-PET images through a graph-based image segmentation method. The proposed framework predicts future morphological changes of lesions with high accuracy. The presented methodology has several benefits over conventional qualitative and semi-quantitative methods, due to its fully quantitative nature and high accuracy in each step of (i) detection, (ii) segmentation, and (iii) feature extraction. To evaluate our proposed computational framework, thirty patients received 2 18F-FDG-PET scans (60 scans total), at two different time points. Metastatic papillary renal cell carcinoma, cerebellar hemongioblastoma, non-small cell lung cancer, neurofibroma, lymphomatoid granulomatosis, lung neoplasm, neuroendocrine tumor, soft tissue thoracic mass, nonnecrotizing granulomatous inflammation, renal cell carcinoma with papillary and cystic features, diffuse large B-cell lymphoma, metastatic alveolar soft part sarcoma, and small cell lung cancer were included in this analysis. The radiotracer accumulation in patients' scans was automatically detected and segmented by the proposed segmentation algorithm. Delineated regions were used to extract shape and textural features, with the proposed adaptive feature extraction framework, as well as standardized uptake values (SUV) of uptake regions, to conduct a broad quantitative analysis. Evaluation of segmentation results indicates that our proposed segmentation algorithm has a mean dice similarity coefficient of 85.75±1.75%. We found that 28 of 68 extracted imaging features were correlated well with SUVmax (p<0.05), and some of the textural features (such as entropy and maximum probability) were superior in predicting morphological changes of radiotracer uptake regions longitudinally, compared to single intensity feature such as SUVmax. We also found that integrating textural features with SUV measurements

  4. Quantification of radiotracer uptake with a dedicated breast PET imaging system

    PubMed Central

    Raylman, Raymond R.; Smith, Mark F.; Kinahan, Paul E.; Majewski, Stan

    2008-01-01

    Tomographic breast imaging techniques can be used to quantify radiotracer uptake in breast and tumor tissue. However, physical processes common to PET imaging can confound accurate quantification. In this investigation, we assessed the effects of these phenomena and tested correction schemes for our new positron emission mammography–tomography system (PEM–PET). The PEM–PET scanner utilizes two sets of rotating planar detector heads. Each unit consists of a 4×3 array of Hamamatsu H8500 flat panel position sensitive photomultipliers coupled to a 96×72 array of 2×2×15 mm3 LYSO detector elements (pitch=2.1 mm). Image reconstruction is performed with a 3D-OSEM algorithm parallelized to run on a multiprocessor computer system. The reconstructed field-of-view is 15×15×15 cm3. Much of the testing procedures were based on NEMA-NU2∕2001 protocols. Count rate losses due to pulse pile-up, image contamination due to acceptance of random coincidences and Compton scatter, and image artifacts produced by photon attenuation were measured. It was found that the system was susceptible to count rate losses when moderate levels of radiation were present in the scanner due to the current design of the event trigger electronics. Application of corrections for Compton scattering, photon attenuation and dead time resulted in improved estimations of 18F concentration in simplified phantom studies. Results from these preliminary studies indicate that the PEM–PET scanner will be useful for the quantification of radiotracer uptake in breast tumors, possibly facilitating early assessment of cancer treatments. PMID:19070233

  5. Radiosynthesis and evaluation of a (99m)Tc-folic acid radiotracer prepared using [(99m)TcN(PNP)](2+) metal fragment.

    PubMed

    Vats, Kusum; Subramanian, Suresh; Mathur, Anupam; Sarma, Haladhar Dev; Banerjee, Sharmila

    2017-03-01

    Folate receptors (FR) are over-expressed on a wide variety of tumor cells and are a potential molecular target for radiolabeled folates. In this respect, several SPECT and PET based radiofolates have been evaluated in the past albeit with their high renal uptake posing limitation towards their clinical use. To overcome this, a new (99m)Tc labeled folic acid was synthesized via the use of [(99m)TcN(PNP)](2+) metal fragment, where the presence of the latter pharmacophore redirects in vivo clearance via the hepatobiliary pathway. In this respect, folic acid was derivatized at the γ-acid group with a cysteine BFCA (bifunctional chelating agent) and subsequently reacted with the preformed [(99m)TcN](2+) intermediate in presence of PNP2 (bisphosphine) ligand, to yield the final complex. While preliminary, in vivo distribution of the complex exhibited high association of activity with liver and intestines and provided support to the rationality of the present design as clearance of labeled folic acid could be effected via the hepatic route, the in vitro studies of the folic acid-cysteine conjugate carried out in KB-31 cells, did not show much promise with reduction in receptor affinity in comparison with the native folic acid. The route followed herein to prepare a folic-acid based radiotracer constitutes the first report of radiolabeling folic acid using the [(99m)TcN(PNP)](2+) as a radiosynthon. Modification in the structure of conjugate by linking the BFCA through a long-chain linker can be envisaged to improve the affinity of [(99m)TcN(PNP)]-folic acid complex towards FRs.

  6. [111In-DOTA]Somatostatin-14 analogs as potential pansomatostatin-like radiotracers - first results of a preclinical study

    PubMed Central

    2012-01-01

    Background In this study, we report on the synthesis, radiolabeling, and biological evaluation of two new somatostatin-14 (SS14) analogs, modified with the universal chelator DOTA. We were interested to investigate if and to what extent such radiotracer prototypes may be useful for targeting sst1-5-expressing tumors in man but, most importantly, to outline potential drawbacks and benefits associated with their use. Methods AT1S and AT2S (DOTA-Ala1-Gly2-c[Cys3-Lys4-Asn5-Phe6-Phe7-Trp8/DTrp8-Lys9-Thr10-Phe11-Thr12-Ser13-Cys14-OH], respectively) were synthesized on the solid support and labeled with 111In. The sst1-5 affinity profile of AT1S/AT2S was determined by receptor autoradiography using [Leu8,dTrp22,125I-Tyr25]SS28 as radioligand. The ability of AT2S to stimulate sst2 or sst3 internalization was qualitatively analyzed by an immunofluorescence-based internalization assay using hsst2- or hsst3-expressing HEK293 cells. Furthermore, the internalization of the radioligands [111In]AT1S and [111In]AT2S was studied at 37 °C in AR4-2J cells endogenously expressing sst2. The in vivo stability of [111In]AT1S and [111In]AT2S was tested by high-performance liquid chromatography analysis of mouse blood collected 5 min after radioligand injection, and biodistribution was studied in normal mice. Selectively for [111In]AT2S, biodistribution was further studied in SCID mice bearing AR4-2J, HEK293-hsst2A+, -hsst3+ or -hsst5+ tumors. Results The new SS14-derived analogs were obtained by solid phase peptide synthesis and were easily labeled with 111In. Both SS14 conjugates, AT1S, and its DTrp8 counterpart, AT2S, showed a pansomatostatin affinity profile with the respective hsst1-5 IC50 values in the lower nanomolar range. In addition, AT2S behaved as an agonist for sst2 and sst3 since it stimulated receptor internalization. The 111In radioligands effectively and specifically internalized into rsst2A-expressing AR4-2J cells with [111In]AT2S internalizing faster than [111In]AT1

  7. Fluorine-18 labeled tracers for PET studies in the neurosciences

    SciTech Connect

    Ding, Yu-Shin; Fowler, J.S.

    1995-12-31

    This chapter focuses on fluorine-18, the positron emitter with the longest half-life, the lowest positron energy and probably, the most challenging chemistry. The incorporation of F-18 into organic compounds presents many challenges, including: the need to synthesize and purify the compound within a 2--3 hour time frame; the limited number of labeled precursor molecules; the need to work on a microscale; and the need to produce radiotracers which are chemically and radiochemically pure, sterile and pyrogen-free, and suitable for intravenous injection. The PET method and F-18 labeling of organic molecules are described followed by highlights of the applications of F-18 labeled compounds in the neurosciences and neuropharmacology. It is important to emphasize the essential and pivotal role that organic synthesis has played in the progression of the PET field over the past twenty years from one in which only a handful of institutions possessed the instrumentation and staff to carry out research to the present-day situation where there are more than 200 PET centers worldwide. During this period PET has become an important scientific tool in the neurosciences, cardiology and oncology. It is important to point out that PET is by no means a mature field. The fact that a hundreds of different F-18 labeled compounds have been developed but only a few possess the necessary selectivity and sensitivity in vivo to track a specific biochemical process illustrates this and underscores a major difficulty in radiotracer development, namely the selection of priority structures for synthesis and the complexities of the interactions between chemical compounds and living systems. New developments in rapid organic synthesis are needed in order to investigate new molecular targets and to improve the quantitative nature of PET experiments.

  8. Minicyclotron-based technology for the production of positron-emitting labelled radiopharmaceuticals

    SciTech Connect

    Barrio, J.R.; Bida, G.; Satyamurthy, N.; Padgett, H.C.; MacDonald, N.S.; Phelps, M.E.

    1983-01-01

    The use of short-lived positron emitters such as carbon 11, fluorine 18, nitrogen 13, and oxygen 15, together with positron-emission tomography (PET) for probing the dynamics of physiological and biochemical processes in the normal and diseased states in man is presently an active area of research. One of the pivotal elements for the continued growth and success of PET is the routine delivery of the desired positron emitting labelled compounds. To date, the cyclotron remains the accelerator of choice for production of medically useful radionuclides. The development of the technology to bring the use of cyclotrons to a clinical setting is discussed. (ACR)

  9. Introduction to Pesticide Labels

    EPA Pesticide Factsheets

    Pesticide product labels provide critical information about how to safely and legally handle and use pesticide products. Unlike most other types of product labels, pesticide labels are legally enforceable. Learn about pesticide product labels.

  10. Evaluation of copper-labeled Cu(II) bis(thiosemicarbazone) complexes as blood flow tracers for positron emission tomography

    SciTech Connect

    Bott, A.J.

    1990-01-01

    Positron emmision tomography (PET) is an imaging technique not widely available for clinical diagnosis due to the costs of producing positron-emitting radiolabels. The development of radiotracers labeled with generator-produced positron emitters would facilitate the use of PET by eliminating the need for an in-house cyclotron. Copper-62 is a generator-produced positron emitter potentially useful for labeling PET radiopharmaceuticals. Copper-62 labeled Cu(II) pyruvaldehyde bis(N[sup 4]-methylthiosemicarbazone), Cu(PTSM), is a proposed PET perfusion tracer of the brain, heart, and kidneys. After IV injection in animals, copper-labeled Cu(PTSM) affords high initial uptake followed by prolonged retention of radiocopper in these organs. This retention is thought to be a result of reductive decomposition of the copper-labeled copper(II) complex by intracellular glutathione, GSH. To validate copper-62 labeled Cu(PTSM) as a myocardial and renal perfusion tracer, the regional radiocopper level afforded by intravenous copper-67 labeled Cu(PTSM) was compared to the absolute blood flow measured with labeled microspheres in normal dog kidneys and surgically infarcted myocardia. In the heart and randomly sectioned kidneys, an excellent correlation resulted. In kidneys dissected to separate anatomical regions, radiocopper levels increased montonically with increasing blood flows for individual dogs, but a linear correlation was observed when data from 12 animals was combined. Should the distribution of Cu(PTSM) vary with naturally occuring GSH fluctuations, the clinical utility of this radiotracer would be limited. Therefore, to validate further copper-62 labeled Cu(PTSM), the biodistribution of copper-67 labeled (PTSM) was determined in GSH-depleted rats. Relatively large GSH reductions in the experimental animals caused only slight changes in the distribution of Cu(PTSM). Another 23 copper-67 labeled compounds were tested.

  11. Development of gamma emitting receptor binding radiotracers for imaging the brain and pancreas. Final technical progress report, March 1, 1988--May 31, 1993

    SciTech Connect

    1996-01-01

    This document give paragraph synopses of results in research on brain and pancreas imaging, using radiotracers. General catagories of research included chemistry, pharmacology, imaging physics, and kinetic modeling. A list of publications is included

  12. Chemistry and biology of radiotracers that target changes in sympathetic and parasympathetic nervous systems in heart disease.

    PubMed

    Eckelman, William C; Dilsizian, Vasken

    2015-06-01

    Following the discovery of the sympathetic and parasympathetic nervous system, numerous adrenoceptor drugs were radiolabeled and potent radioligands were prepared in order to image the β-adrenergic and the muscarinic systems. But the greatest effort has been in preparing noradrenaline analogs, such as norepinephrine, (11)C-metahydroxyephedrine, and (123)I-metaiodobenzylguanidine that measure cardiac sympathetic nerve varicosities. Given the technical and clinical challenges in designing and validating targeted adrenoceptor-binding radiotracers, namely the heavily weighted flow dependence and relatively low target-to-background ratio, both requiring complicated mathematic analysis, and the inability of targeted adrenoceptor radioligands to have an impact on clinical care of heart disease, the emphasis has been on radioligands monitoring the norepinephrine pathway. The chemistry and biology of such radiotracers, and the clinical and prognostic impact of these innervation imaging studies in patients with heart disease, are examined.

  13. Bilateral axillary lymph node uptake of radiotracer during lower extremity and scrotal lymphoscintigraphy in a case of primary scrotal lymphoedema

    PubMed Central

    Jain, Anuj; Jaimini, Abhinav

    2011-01-01

    Lymphoscintigraphy is a useful technique for the evaluation of lymphatic function in the presence of limb swelling. The authors report a case where genital swelling in a 20-year-old man was investigated by lymphoscintigraphy. We performed lower limb lymphoscintigraphy and scrotal lymphoscintigraphy in the patient on two different days. Lower limb revealed dermal backflow pattern in lower limbs, inguinoscrotal reflux of the lymph and unexpected avid radiotracer uptake in the axillae bilaterally. Scrotal lymphoscintigraphy revealed slow movement of the lymph from the scrotal skin and again unexpected avid radiotracer uptake in the axillae bilaterally. Findings were concluded as congenital hypoplasia of lymphatics in lower limbs, congenital lymphectasia/compensatory megalymphatics in scrotum and aberrant lymphatic pathway, possibly due to malfunctioning/nonfunctioning thoracic duct. PMID:23559718

  14. Preparation of ⁶⁸Ga-labelled DOTA-peptides using a manual labelling approach for small-animal PET imaging.

    PubMed

    Romero, Eduardo; Martínez, Alfonso; Oteo, Marta; García, Angel; Morcillo, Miguel Angel

    2016-01-01

    (68)Ga-DOTA-peptides are a promising PET radiotracers used in the detection of different tumours types due to their ability for binding specifically receptors overexpressed in these. Furthermore, (68)Ga can be produced by a (68)Ge/(68)Ga generator on site which is a very good alternative to cyclotron-based PET isotopes. Here, we describe a manual labelling approach for the synthesis of (68)Ga-labelled DOTA-peptides based on concentration and purification of the commercial (68)Ga/(68)Ga generator eluate using an anion exchange-cartridge. (68)Ga-DOTA-TATE was used to image a pheochromocytoma xenograft mouse model by a microPET/CT scanner. The method described provides satisfactory results, allowing the subsequent (68)Ga use to label DOTA-peptides. The simplicity of the method along with its implementation reduced cost, makes it useful in preclinical PET studies.

  15. Establishment of a trimodality analytical platform for tracing, imaging and quantification of gold nanoparticles in animals by radiotracer techniques.

    PubMed

    Chen, Chien-Hung; Lin, Fong-Sian; Liao, Wei-Neng; Liang, Sanching L; Chen, Min-Hua; Chen, Yo-Wen; Lin, Wan-Yu; Hsu, Ming-Hua; Wang, Mei-Ya; Peir, Jinn-Jer; Chou, Fong-In; Chen, Ching-Ya; Chen, Sih-Yu; Huang, Su-Chin; Yang, Mo-Hsiung; Hueng, Dueng-Yuan; Hwu, Yeukuang; Yang, Chung-Shi; Chen, Jen-Kun

    2015-01-06

    This study aims to establish a (198)Au-radiotracer technique for in vivo tracing, rapid quantification, and ex vivo visualization of PEGylated gold nanoparticles (GNPs) in animals, organs and tissue dissections. The advantages of GNPs lie in its superior optical property, biocompatibility and versatile conjugation chemistry, which are promising to develop diagnostic probes and drug delivery systems. (198)Au is used as a radiotracer because it simultaneously emits beta and gamma radiations with proper energy and half-life; therefore, (198)Au can be used for bioanalytical purposes. The (198)Au-tagged radioactive gold nanoparticles ((198)Au-GNPs) were prepared simply by irradiating the GNPs in a nuclear reactor through the (197)Au(n,γ)(198)Au reaction and subsequently the (198)Au-GNPs were subjected to surface modification with polyethylene glycol to form PEGylated (198)Au-GNPs. The (198)Au-GNPs retained physicochemical properties that were the same as those of GNP before neutron irradiation. Pharmacokinetic and biodisposition studies were performed by intravenously injecting three types of (198)Au-GNPs with or without PEGylation into mice; the γ radiation in blood specimens and dissected organs was then measured. The (198)Au-radiotracer technique enables rapid quantification freed from tedious sample preparation and shows more than 95% recovery of injected GNPs. Clinical gamma scintigraphy was proved feasible to explore spatial- and temporal-resolved biodisposition of (198)Au-GNPs in living animals. Moreover, autoradiography, which recorded beta particles from (198)Au, enabled visualizing the heterogeneous biodisposition of (198)Au-GNPs in different microenvironments and tissues. In this study, the (198)Au-radiotracer technique facilitated creating a trimodality analytical platform for tracing, quantifying and imaging GNPs in animals.

  16. PET and SPECT Radiotracers to Assess Function and Expression of ABC Transporters in Vivo

    PubMed Central

    Mairinger, Severin; Erker, Thomas; Müller, Markus; Langer, Oliver

    2013-01-01

    Adenosine triphosphate-binding cassette (ABC) transporters, such as P-glycoprotein (Pgp, ABCB1), breast cancer resistance protein (BCRP, ABCG2) and multidrug resistance-associated proteins (MRPs) are expressed in high concentrations at various physiological barriers (e.g. blood-brain barrier, blood-testis barrier, blood-tumor barrier), where they impede the tissue accumulation of various drugs by active efflux transport. Changes in ABC transporter expression and function are thought to be implicated in various diseases, such as cancer, epilepsy, Alzheimer’s and Parkinson’s disease. The availability of a non-invasive imaging method which allows for measuring ABC transporter function or expression in vivo would be of great clinical use in that it could facilitate the identification of those patients that would benefit from treatment with ABC transporter modulating drugs. To date three different kinds of imaging probes have been described to measure ABC transporters in vivo: i) radiolabelled transporter substrates ii) radiolabelled transporter inhibitors and iii) radiolabelled prodrugs which are enzymatically converted into transporter substrates in the organ of interest (e.g. brain). The design of new imaging probes to visualize efflux transporters is inter alia complicated by the overlapping substrate recognition pattern of different ABC transporter types. The present article will describe currently available ABC transporter radiotracers for positron emission tomography (PET) and single-photon emission computed tomography (SPECT) and critically discuss strengths and limitations of individual probes and their potential clinical applications. PMID:21434859

  17. Imaging cardiac SCN5A using the novel F-18 radiotracer radiocaine

    PubMed Central

    Hooker, Jacob M.; Strebl, Martin G.; Schroeder, Frederick A.; Wey, Hsiao-Ying; Ambardekar, Amrut V.; McKinsey, Timothy A.; Schoenberger, Matthias

    2017-01-01

    The key function of the heart, a well-orchestrated series of contractions, is controlled by cardiac action potentials. These action potentials are initiated and propagated by a single isoform of voltage gated sodium channels – SCN5A. However, linking changes in SCN5A expression levels to human disease in vivo has not yet been possible. Radiocaine, an F-18 radiotracer for positron emission tomography (PET), is the first SCN5A imaging agent in the heart. Explants from healthy and failing human hearts were compared using radiocaine autoradiography to determine that the failing heart has ~30% lower SCN5A levels - the first evidence of changes in SCN5A expression in humans as a function of disease. Paving the way for translational imaging, radiocaine proved to exhibit high in vivo specific binding to the myocardium of non-human primates. We envision that SCN5A measurements using PET imaging may serve as a novel diagnostic tool to stratify arrhythmia risk and assess for progression of heart failure in patients with a broad spectrum of cardiovascular diseases. PMID:28205593

  18. Biochemical quantification of sympathetic nervous activity in humans using radiotracer methodology: fallibility of plasma noradrenaline measurements

    SciTech Connect

    Esler, M.; Leonard, P.; O'Dea, K.; Jackman, G.; Jennings, G.; Korner, P.

    1982-01-01

    We have developed radiotracer techniques for studying noradrenaline kinetics, to assess better sympathetic nervous system function in humans. Tritiated l-noradrenaline was infused intravenously (0.35 microCi/m2/min) to plateau plasma concentration. Noradrenaline plasma clearance was calculated from plasma tritiated noradrenaline concentration at steady state, and the rate of spillover of noradrenaline to plasma derived from plasma noradrenaline specific radioactivity. Mean noradrenaline spillover at rest in 34 normal subjects was 0.33 micrograms/m2/min (range 0.17-0.61 micrograms/m2/min). Predictably, noradrenaline spillover was reduced in patients with subnormal sympathetic nervous system activity, 0.16 +/- 0.09 micrograms/m2/min in eight patients with idiopathic peripheral autonomic insufficiency, and 0.11 +/- 0.07 micrograms/m2/min (mean +/- SD) in six patients with essential hypertension treated with clonidine (0.45 mg daily). Noradrenaline line plasma clearance in normal subjects was 1.32 +/- 0.28 L/m2/min. Clearance fell with age, causing the previously described rise in plasma noradrenaline concentration with aging. Unexpected effects of drugs were encountered, for example chronic beta-adrenergic blockade in patients with essential hypertension reduced noradrenaline clearance. Plasma noradrenaline concentration measurements were not in agreement with noradrenaline release rate values, and do not reliably indicate sympathetic nervous system activity, in instances such as these where noradrenaline clearance is abnormal.

  19. In-situ radiotracer and electrochemical study of sulfate accumulation on Al 2024 alloy

    SciTech Connect

    Kolics, A.; Thomas, A.E.; Wieckowski, A.

    1995-12-01

    We have applied radiotracer, electrochemical and ultrahigh vacuum techniques to study sulfate accumulation in passive films on pure aluminum and Al 2024 alloy in 0.1 M NaClO{sub 4} containing 0.1 mM Na{sub 2}SO{sub 4}. We have found that the sulfate coverage is pH and electrode potential dependent and that sulfate is bonded to the surface in two distinctively different ways. While the breakdown of the passive film results in sulfate removal, the subsequent repassivation reintroduces the sulfate anion into the passive film. There is a strong tendency of sulfate to remain in the passive film which explains the inhibitive properties of sulfate in aluminum corrosion. Our data reveal that the anomalous sulfate accumulation during the negative-going polarization can be attributed to the copper content of the alloy surface. The formation of copper-containing nodules determines the electrode potential threshold below which sulfate anions desorb. 20 refs., 4 figs.

  20. Investigating phosphorus uptake in anoxic and sulfidic surface sediments with 33P radiotracer experiments

    NASA Astrophysics Data System (ADS)

    Dijkstra, Nikki; Kraal, Peter; Gonzalez, Santiago; Slomp, Caroline

    2016-04-01

    Phosphorus (P) is a key nutrient for marine organisms. Enhanced P availability in the water column can fuel algal blooms and the development of bottom water anoxia. Recently, it was suggested that micro-organisms in sediments overlain by anoxic and sulfidic bottom waters might take up dissolved P and form Fe(II)-P minerals, thereby enhancing P removal. In this study, we investigated the uptake of P in surface sediments with 33P radiotracer experiments. The sediments were recovered from the anoxic and sulfidic deep basin of the Black Sea and, for comparison, from the adjacent oxic shelf. Results suggest a very fast sedimentary uptake of 33P at all sites but in particular for sediments from the oxic shelf. At all sites, most 33P was sequestered in the citrate-dithionite-bicarbonate-(CDB)-extractable sediment P fraction. No significant differences with abiotic controls were observed, implying that micro-organisms were not directly involved in the P uptake. Whereas 33P uptake by the oxic shelf sediment was likely controlled by sorption of 33P to iron(Fe)-(oxyhydr)oxides, the nature of the CDB-extractable P fraction in the deep basin sediments remains unclear. We discuss whether authigenic formation of Fe(II)-P minerals or fast adsorption of P to calcites may explain our findings.

  1. Agonist signalling properties of radiotracers used for imaging of dopamine D2/3 receptors

    PubMed Central

    2014-01-01

    Background Dopamine D2/3 receptor (D2/3R) agonist radiopharmaceuticals are considered superior to antagonists to detect dopamine release, e.g. induced by amphetamines. Agonists bind preferentially to the high-affinity state of the dopamine D2R, which has been proposed as the reason why agonists are more sensitive to detect dopamine release than antagonist radiopharmaceuticals, but this theory has been challenged. Interestingly, not all agonists similarly activate the classic cyclic adenosine mono phosphate (cAMP) and the ?-arrestin-2 pathway, some stimulate preferentially one of these pathways; a phenomenon called biased agonism. Because these pathways can be affected separately by pathologies or drugs (including dopamine releasers), it is important to know how agonist radiotracers act on these pathways. Therefore, we characterized the intracellular signalling of the well-known D2/3R agonist radiopharmaceuticals NPA and PHNO and of several novel D2/3R agonists. Methods cAMP accumulation and ?-arrestin-2 recruitment were measured on cells expressing human D2R. Results All tested agonists showed (almost) full agonism in both pathways. Conclusions The tested D2/3R agonist radiopharmaceuticals did not exhibit biased agonism in vitro. Consequently, it is likely that drugs (including psychostimulants like amphetamines) and/or pathologies that influence the cAMP and/or the ?-arrestin-2 pathway may influence the binding of these radiopharmaceuticals. PMID:25977878

  2. Bioavailability and distribution and of ceria nanoparticles in simulated aquatic ecosystems, quantification with a radiotracer technique.

    PubMed

    Lu, Kai; Zhang, Zhiyong; He, Xiao; Ma, Yuhui; Zhou, Kebin; Zhang, Haifeng; Bai, Wei; Ding, Yayun; Wu, Zhenqiang; Zhao, Yuliang; Chai, Zhifang

    2010-12-01

    Although the presence of manufactured nanoparticles in the aquatic environment is still largely undocumented, their release could certainly occur in the future, particularly via municipal treatment plant effluents of cities supporting nano-industries. To get an initial estimate of the environmental behavior of nanomaterials, we investigated the distribution and accumulation of ceria nanoparticles in simulated aquatic ecosystems which included aquatic plant, shellfish, fish, water, and sediment using a radiotracer technique. Radioactive ceria (141CeO2) nanoparticles with a diameter of ca. 7 nm were synthesized by a precipitation method and added to the simulated aquatic ecosystems. The results indicate that the concentration of ceria nanoparticles in water decreased to a steady-state value after 3 days; meanwhile, the concentrations of ceria nanoparticles in the aquatic plant and sediment increased to their highest values. The distribution and accumulation characteristics of ceria nanoparticles in various aquatic organisms were different. Ceratophyllum demersum showed a high ability of accumulation of ceria nanoparticles from water.

  3. [18F]Fluoro-hydroxyphenethylguanidines: Efficient Synthesis and Comparison of Two Structural Isomers as Radiotracers of Cardiac Sympathetic Innervation.

    PubMed

    Jung, Yong-Woon; Jang, Keun Sam; Gu, Guie; Koeppe, Robert A; Sherman, Phillip S; Quesada, Carole A; Raffel, David M

    2017-03-21

    Fluorine-18 labeled phenethylguanidines are currently under development in our laboratory as radiotracers for quantifying regional cardiac sympathetic nerve density using PET imaging techniques. In this study, we report an efficient synthesis of 18F-hydroxyphenethylguanidines consisting of nucleophilic aromatic [18F]fluorination of a protected diaryliodonium salt precursor followed by a single deprotection step to afford the desired radiolabeled compound. This approach has been shown to reliably produce 4-[18F]fluoro-m-hydroxyphenethylguanidine ([18F]4F-MHPG, [18F]1) and its structural isomer 3-[18F]fluoro-p-hydroxyphenethylguanidine ([18F]3F-PHPG, [18F]2) with good radiochemical yields. Preclinical evaluations of [18F]2 in non-human primates were performed to compare its imaging properties, metabolism, and myocardial kinetics with those obtained previously with [18F]1. The results of these studies have demonstrated that [18F]2 exhibits imaging properties comparable to those of [18F]1. Myocardial tracer kinetic analysis of each tracer provides quantitative metrics of cardiac sympathetic nerve density. Based on these findings, first-in-human PET studies with [18F]1 and [18F]2 are currently in progress to assess their ability to accurately measure regional cardiac sympathetic denervation in patients with heart disease, with the ultimate goal of selecting a lead compound for further clinical development.

  4. Labeling of monoclonal antibodies with radionuclides

    SciTech Connect

    Bhargava, K.K.; Acharya, S.A. )

    1989-07-01

    Antibodies, specifically monoclonal antibodies, are potentially very useful and powerful carriers of therapeutic agents to target tissues and diagnostic agents. The loading or charging of antibodies with agents, especially radiotracers, is reviewed here. The choice of radioisotope for immunodetection and/or immunotherapy is based on its availability, half-life, nature of the radiation emitted, and the metabolic pathways of the radionuclide in the body. Most important of all are the derivatization techniques available for labeling the antibody with the given radionuclide. Isotopes of iodine and divalent metal ions are the most commonly used radionuclides. Antibodies labeled with iodine at tyrosine residues are metabolized rapidly in vivo. This leads to the incorporation of metabolized radioactive iodine into various tissues, mainly the thyroid gland and stomach, and to the accumulation of high levels of circulating iodine in the blood, which masks tumor uptake considerably. To overcome these limitations, the use of iodohippurate as an iodine-anchoring molecule to the protein should be considered. When divalent or multivalent metal ions are used as the preferred radionuclide, bifunctional chelating reagents such as EDTA or DTPA are first coupled to the protein or antibody. These chelating molecules are attached to the protein by formation of an isopeptide linkage between the carboxylate of the chelating reagent and the amino group of the protein. Several procedures are available to generate the isopeptide linkage. When the anchoring of the chelating agent through isopeptide linkage results in the inactivation of the antibody, periodate oxidation of the carbohydrate moiety of the antibody, followed by reductive coupling of chelator, could be considered as an alternative. There is still a need for better, simpler, and more direct methods for labeling antibodies with radionuclides. 78 references.

  5. SU-E-I-80: Beta-Minus Emitting Radiotracers Improves Molecular Endoscopy

    SciTech Connect

    Carpenter, C; Ma, X; Sun, C; Pratx, G; Cheng, Z; Xing, L

    2014-06-01

    Purpose: Molecular Endoscopy using Cerenkov Luminescence can be used to monitor the distribution of many clinically-available PET and SPECT probes for endoscopic applications. A main limitation of Cerenkov is its limited sensitivity to small concentrations of radiotracer when using light guides s. Herein we demonstrate that the use of a high energy beta emitting radioisotope, exemplified here with 90Y provides superior sensitivity to 18F because of its higher light output and its lack of corresponding gamma emission. Methods: A series of phantom experiments were performed to compare the sensitivity and noise of the CLE system for imaging 90Y and 18F. Three vials of known concentrations of 90Y (0.008 μCi, 0.08 μCi, 1 μCi) were placed in centrifuge tubes and isolated from each other. One vial of 18F (100 μCi) was placed in the imaging chamber and imaged over the course of decay (19 hours, 43 minutes, or ∼10 half-lives). Image time-points were formed from 5-minute integrations. Results: Using an SNR of 10 to define the noise-floor, the 90Y minimum detectable activity was 0.056 μCi. To the contrast, the minimum detectable activity for 18F was 11.63 μCi. These data demonstrate a 207-fold improvement in SNR of 90Y compared to 18F, when controlled for activity. Conclusion: This study demonstrated that a pure β- radionuclide such as 90Y be used is superior to 18F for Cerenkov Endoscopy. Further study is needed to demonstrate its utility in preclinical studies, endoscopic applications, intraoperative, and radiotherapy applications.

  6. Improving AMS Detection of the Biomedical Radiotracer 41Ca with Segmented Radio-Frequency Quadrupoles

    NASA Astrophysics Data System (ADS)

    Alary, Jean-Francois; Javahery, Gholamreza; Kieser, William E.; Litherland, Albert E.; Cousins, Lisa M.

    41Ca is an important biomedical radiotracer finding many applications in biological, nutritional and medical studies. The detection of 41Ca by AMS is however limited by an important background signal of 41K originating from biological samples and from contaminated cesium in the source. An approach consisting of using PbF2-assisted in-source fluorination in combination with an Isobar Separator for Anions (ISA), a device incorporating a low energy radio frequency quadrupole (RFQ) gas cell, promises to push down the limit of detection of 41Ca attainable on small (<3 MV) accelerator mass spectrometry (AMS) systems by several orders of magnitude. Such on-line reduction of 41K should also result in a simplification of biological sample preparation and less concern about variable 41K contamination of the cesium beam. The selective collision-induced fragmentation of KF3- versus CaF3-, occurring in the gas cell of an ISA equipped with a double segment RFQ, have been reported earlier1), leading to K being suppressed by a factor of 1e4 over Ca. We present here the future configuration of the ISA, redesigned using multi-segmented RFQ to enhance further this effect and improve transmission through the gas cell. A segmented RFQ is an appropriate tool to finely control ion energy down to the few eV's separating the fragmentation energies of the two fluoride species. This pre-commercial ISA destined to be used at the newly established A. E. Lalonde AMS laboratory at University of Ottawa (Canada) will be presented. Some practicalities of integrating a low energy RFQ-based device in a high energy AMS system will also be discussed.

  7. A radiotracer study of cerium and manganese uptake onto suspended particles in Chesapeake Bay

    SciTech Connect

    Moffett, J.W. )

    1994-01-01

    The oxidation kinetics of Ce(III) and Mn(II) were studied in Chesapeake Bay in March and July 1990 to establish the role of water column redox processes in contributing to Ce anomalies observed in this estuary (SHOLKOVITZ and ELDERFIELD, 1988; SHOLKOVITZ et al., 1992). Oxidation was measured by adding Mn(II) and Ce(III) to freshly collected water samples as radiotracers and measuring their uptake onto the ambient suspended particle assemblage. Mn(II) oxidation was measured by following the uptake of [sup 54]Mn(II) onto suspended particles and utilizing protocols established by other workers to distinguish oxidation from Mn(II) adsorption. The same protocols were applicable to Ce(III), using [sup 139]Ce(III), and were supported by the use of [sup 152]Eu(III) as a nonredox reactive control. Specific rates of Ce(III) and MN(II) oxidation measured at a station in the North Bay (depth = 4 m) in July were 2016% per day and 4032% per day, respectively. In March, at the same station, the specific rate of Mn(II) of oxidation was only 1-% per day, and Ce(III) oxidation was undetectable. Both Ce(III) and Mn(II) oxidation processes were inhibited by azide, indicating that they were microbially mediated. The seasonal differences probably reflect strong seasonal variation in the abundance of Mn oxidizing bacteria. No Ce(III) oxidation occured in samples collected below the oxic/anoxic interface in July. The specific rates of oxidation for both elements were over 1000 times higher than those measured in the Sargasso Sea. However, the specific rates for Ce(III) and Mn(II) were very similar to each other. This fact, coupled with similar spatial and temporal trends for specific oxidation rates, suggests a common mechanism of oxidation of both elements which may be significant in a wide range of marine environments.

  8. Distribution and dosimetry of 111In-labeled platelets.

    PubMed

    Robertson, J S; Dewanjee, M K; Brown, M L; Fuster, V; Cesebro, J H

    1981-07-01

    The distribution of 111In-labeled platelets was studied in five young, healthy men. The radioactivity in the lungs, heart, liver, spleen, kidneys, and testes was determined from areas-of-interest in computed gamma-camera scans at intervals up to 75 hours after injection. After the first four hours, the activity in each organ studied except the liver and kidney decreased at roughly the physical decay rate. In the liver and kidney, the curves were relatively flat, indicating continued accumulation of the radiotracer. The calculated mean radiation absorbed dose per unit administered activity was 0.60 +/- 0.07 rad/mCi (0.16 +/- 0.02 Gy/GBq) for the total body, and was 34 +/- 6 rad/mCi (9.0 +/- 1.5 Gy/GBq) for the spleen.

  9. Development of [F-18]-Labeled Amyloid Imaging Agents for PET

    SciTech Connect

    Mathis, CA

    2007-05-09

    The applicant proposes to design and synthesize a series of fluorine-18-labeled radiopharmaceuticals to be used as amyloid imaging agents for positron emission tomography (PET). The investigators will conduct comprehensive iterative in vitro and in vivo studies based upon well defined acceptance criteria in order to identify lead agents suitable for human studies. The long term goals are to apply the selected radiotracers as potential diagnostic agents of Alzheimer's disease (AD), as surrogate markers of amyloid in the brain to determine the efficacy of anti-amyloid therapeutic drugs, and as tools to help address basic scientific questions regarding the progression of the neuropathology of AD, such as testing the "amyloid cascade hypothesis" which holds that amyloid accumulation is the primary cause of AD.

  10. In vivo vulnerability to competition by endogenous dopamine: comparison of the D2 receptor agonist radiotracer (-)-N-[11C]propyl-norapomorphine ([11C]NPA) with the D2 receptor antagonist radiotracer [11C]-raclopride.

    PubMed

    Narendran, Rajesh; Hwang, Dah-Ren; Slifstein, Mark; Talbot, Peter S; Erritzoe, David; Huang, Yiyun; Cooper, Thomas B; Martinez, Diana; Kegeles, Lawrence S; Abi-Dargham, Anissa; Laruelle, Marc

    2004-06-01

    (-)-N-Propyl-norapomorphine (NPA) is a full dopamine (DA) D2 receptor agonist and [11C]NPA is a suitable radiotracer to image D2 receptors configured in a state of high affinity for agonists with positron emission tomography (PET). In this study the vulnerability of the in vivo binding of [11C]NPA to acute fluctuation in synaptic DA was assessed with PET in baboons and compared to that of the reference D2 receptor antagonist radiotracer [11C]raclopride. Three male baboons were studied with [11C]raclopride and [11C]NPA under baseline conditions and following administration of the potent DA releaser amphetamine (0.3, 0.5, and 1.0 mg kg(-1) i.v.). Kinetic modeling with an arterial input function was used to derive the striatal specific-to-nonspecific equilibrium partition coefficient (V3"). [11C]Raclopride V3" was reduced by 24 +/- 10%, 32 +/- 6%, and 44 +/- 9% following amphetamine doses of 0.3, 0.5, and 1.0 mg kg(-1), respectively. [11C]NPA V3" was reduced by 32 +/- 2%, 45 +/- 3%, and 53 +/- 9% following amphetamine doses of 0.3, 0.5, and 1.0 mg kg(-1), respectively. Thus, endogenous DA was more effective at competing with [11C]NPA binding compared to [11C]raclopride binding, a finding consistent with the pharmacology of these tracers (agonist vs. antagonist). These results also suggest that 71% of D2 receptors are configured in a state of high affinity for agonists in vivo. In conclusion, [11C]NPA might provide a superior radiotracer to probe presynaptic DA function with PET in health and disease.

  11. Development of a 99Mo/99mTc generator using alumina microspheres for industrial radiotracer applications.

    PubMed

    Dash, Ashutosh; Chakravarty, Rubel; Ram, Ramu; Pillai, K T; Yadav, Yugandhara Y; Wagh, D N; Verma, Rakesh; Biswas, Sujoy; Venkatesh, Meera

    2012-01-01

    A chromatographic (99)Mo/(99m)Tc generator for industrial applications has been developed using alumina microspheres synthesized through sol-gel process to obtain (99m)Tc in both aqueous and non-aqueous media. The sorbent was mesoporous, mechanically strong and possessed high surface area. (99m)Tc could be eluted from generator system using either acetone or 0.9% NaCl solution with appreciably high yields and high radiochemical as well as radionuclidic purity. The facile, versatile generator provides an efficient way to access (99m)Tc at industrial sites for radiotracer applications.

  12. Preclinical radiation dosimetry for the novel SV2A radiotracer [18F]UCB-H

    PubMed Central

    2013-01-01

    Background [18F]UCB-H was developed as a novel radiotracer with a high affinity for synaptic vesicle protein 2A, the binding site for the antiepileptic levetiracetam. The objectives of this study were to evaluate the radiation dosimetry of [18F]UCB-H in a preclinical trial and to determine the maximum injectable dose according to guidelines for human biomedical research. The radiation dosimetry was derived by organ harvesting and dynamic micro positron emission tomography (PET) imaging in mice, and the results of both methods were compared. Methods Twenty-four male C57BL-6 mice were injected with 6.96 ± 0.81 MBq of [18F]UCB-H, and the biodistribution was determined by organ harvesting at 2, 5, 10, 30, 60, and 120 min (n = 4 for each time point). Dynamic microPET imaging was performed on five male C57BL-6 mice after the injection of 9.19 ± 3.40 MBq of [18F]UCB-H. A theoretical dynamic bladder model was applied to simulate urinary excretion. Human radiation dose estimates were derived from animal data using the International Commission on Radiological Protection 103 tissue weighting factors. Results Based on organ harvesting, the urinary bladder wall, liver and brain received the highest radiation dose with a resulting effective dose of 1.88E-02 mSv/MBq. Based on dynamic imaging an effective dose of 1.86E-02 mSv/MBq was calculated, with the urinary bladder wall and liver (brain was not in the imaging field of view) receiving the highest radiation. Conclusions This first preclinical dosimetry study of [18F]UCB-H showed that the tracer meets the standard criteria for radiation exposure in clinical studies. The dose-limiting organ based on US Food and Drug Administration (FDA) and European guidelines was the urinary bladder wall for FDA and the effective dose for Europe with a maximum injectable single dose of approximately 325 MBq was calculated. Although microPET imaging showed significant deviations from organ harvesting, the Pearson’s correlation coefficient

  13. Comparison of three devices for automated infusion of positron-emitting radiotracers.

    PubMed

    Miyaji, Noriaki; Miwa, Kenta; Wagatsuma, Kei; Murata, Taisuke; Umeda, Takuro; Terauchi, Takashi; Koizumi, Mitsuru

    2017-03-09

    The administration accuracy and precision of automated infusion device for positron-emitting radiotracer is directly associated with bias and variance in standardized uptake values (SUV) of (18)F-FDG PET/CT. Therefore, the accuracy of such devices must be confirmed and calibrated at locations where they are used. The present study aimed to validate the administration accuracy of three automated infusion devices for quantitative PET assessment. Methods: Temporal variations as well as variations in radioactive concentrations and dispensed volumes of (18)F-FDG were determined for the M-130, the AI-300 (both Sumitomo Heavy Industries Ltd., Japan), and the UG-05 (Universal Giken Co. Ltd., Japan) automated infusion devices. The total test dispensed volumes were 25, 20 and 18.5 mL, respectively. A reference value was generated by measuring amounts of radioactivity using a standard dose calibrator. Administration accuracy was validated according to the criteria of the Japanese Society of Nuclear Medicine (JSNM). Results: Temporal variation in the M-130 and UG-05 for specified 185 MBq was a relatively stable in the range -1.60 to 0.92% and 1.16 to 5.35%, respectively, whereas that in the AI-300 was -0.55 to 8.68%. For M-130 and UG-05, the difference between measured and reference value was in the range -5 to 5%. The values measured by the AI-300 deviated from the reference values by a maximum of 30%, which depends on radioactive concentration and dispensed volume of (18)F-FDG. Conclusion: The administration accuracy of the AI-300 varied considerably under different conditions, but a software update might somewhat improve this. Our findings indicate that dispensed volumes of (18)F-FDG should be carefully considered when the radioactive concentration is high. Administration accuracy should be regularly confirmed at each location to maintain the quality of quantitative PET assessment. The present study provides useful information about how to confirm the administration

  14. Radionuclide labeling and evaluation of candidate radioligands for PET imaging of histone deacetylase in the brain.

    PubMed

    Seo, Young Jun; Muench, Lisa; Reid, Alicia; Chen, Jinzhu; Kang, Yeona; Hooker, Jacob M; Volkow, Nora D; Fowler, Joanna S; Kim, Sung Won

    2013-12-15

    Histone deacetylases (HDACs) regulate gene expression by inducing conformational changes in chromatin. Ever since the discovery of a naturally occurring HDAC inhibitor, trichostatin A (TSA) stimulated the recent development of suberoylanilide (SAHA, Zolinza®), HDAC has become an important molecular target for drug development. This has created the need to develop specific in vivo radioligands to study epigenetic regulation and HDAC engagement for drug development for diseases including cancer and psychiatric disorders. 6-([(18)F]Fluoroacetamido)-1-hexanoicanilide ([(18)F]FAHA) was recently developed as a HDAC substrate and shows moderate blood-brain barrier (BBB) permeability and specific signal (by metabolic trapping/or deacetylation) but rapid metabolism. Here, we report the radiosynthesis of two carbon-11 labeled candidate radiotracers (substrate- and inhibitor-based radioligand) for HDAC and their evaluation in non-human primate brain. PET studies showed very low brain uptake and rapid metabolism of both labeled compounds but revealed a surprising enhancement of brain penetration by F for H substitution when comparing one of these to [(18)F]FAHA. Further structural refinement is needed for the development of brain-penetrant, metabolically stable HDAC radiotracers and to understand the role of fluorine substitution on brain penetration.

  15. (18)F-labeled positron emission tomographic radiopharmaceuticals in oncology: an overview of radiochemistry and mechanisms of tumor localization.

    PubMed

    Vallabhajosula, Shankar

    2007-11-01

    Molecular imaging is the visualization, characterization, and measurement of biological processes at the molecular and cellular levels in a living system. At present, positron emission tomography/computed tomography (PET/CT) is one the most rapidly growing areas of medical imaging, with many applications in the clinical management of patients with cancer. Although [(18)F]fluorodeoxyglucose (FDG)-PET/CT imaging provides high specificity and sensitivity in several kinds of cancer and has many applications, it is important to recognize that FDG is not a "specific" radiotracer for imaging malignant disease. Highly "tumor-specific" and "tumor cell signal-specific" PET radiopharmaceuticals are essential to meet the growing demand of radioisotope-based molecular imaging technology. In the last 15 years, many alternative PET tracers have been proposed and evaluated in preclinical and clinical studies to characterize the tumor biology more appropriately. The potential clinical utility of several (18)F-labeled radiotracers (eg, fluoride, FDOPA, FLT, FMISO, FES, and FCH) is being reviewed by several investigators in this issue. An overview of design and development of (18)F-labeled PET radiopharmaceuticals, radiochemistry, and mechanism(s) of tumor cell uptake and localization of radiotracers are presented here. The approval of clinical indications for FDG-PET in the year 2000 by the Food and Drug Administration, based on a review of literature, was a major breakthrough to the rapid incorporation of PET into nuclear medicine practice, particularly in oncology. Approval of a radiopharmaceutical typically involves submission of a "New Drug Application" by a manufacturer or a company clearly documenting 2 major aspects of the drug: (1) manufacturing of PET drug using current good manufacturing practices and (2) the safety and effectiveness of a drug with specific indications. The potential routine clinical utility of (18)F-labeled PET radiopharmaceuticals depends also on

  16. A generally adoptable radiotracing method for tracking carbon nanotubes in animals

    NASA Astrophysics Data System (ADS)

    Deng, Xiaoyong; Yang, Shengtao; Nie, Haiyu; Wang, Haifang; Liu, Yuanfang

    2008-02-01

    Carbon nanotube (CNT) mediated drug delivery systems have currently aroused a great deal of interest. Such delivery systems for drugs, proteins and genes have been preliminarily studied using cellular and animal models. For the further study of the pharmacokinetics and related biological behaviours of CNTs in vivo, a fast and convenient tracing method is particularly demanded. In this paper, we developed a generally adoptable tracing method for the biodistribution study of functionalized CNTs in vivo. Taurine covalently functionalized multi-walled carbon nanotubes (tau-MWNTs) and Tween-80 wrapped MWNTs (Tween-MWNTs) were labelled with 125I, and then their distribution in mice was determined. It is interesting that Tween-80 can reduce the RES uptake of MWNTs remarkably. The resulting distribution of 125I-tau-MWNTs was very consistent with that using 14C-taurine-MWNTs as the CNTs tracer, which means the easy 125I labelling method is reliable and effective.

  17. Semiotic labelled deductive systems

    SciTech Connect

    Nossum, R.T.

    1996-12-31

    We review the class of Semiotic Models put forward by Pospelov, as well as the Labelled Deductive Systems developed by Gabbay, and construct an embedding of Semiotic Models into Labelled Deductive Systems.

  18. Soil Fumigant Labels

    EPA Pesticide Factsheets

    The 2012 updated pesticide labels include new safety requirements for buffer zones and related measures. Find labels for each different type of fumigant: chloropicrin, dazomet, dimethyl disulfide, metam sodium/potassium, and methyl bromide.

  19. Electronic Submission of Labels

    EPA Pesticide Factsheets

    Pesticide registrants can provide draft and final labels to EPA electronically for our review as part of the pesticide registration process. The electronic submission of labels by registrants is voluntary but strongly encouraged.

  20. Soil Fumigant Labels - Dazomet

    EPA Pesticide Factsheets

    Updated labels include new safety requirements for buffer zones and related measures. Find information from the Pesticide Product Labeling System (PPLS) for products such as Basamid G, manufactured by Amvac.

  1. Mental Labels and Tattoos

    ERIC Educational Resources Information Center

    Hyatt, I. Ralph

    1977-01-01

    Discusses the ease with which mental labels become imprinted in our system, six basic axioms for maintaining negative mental tattoos, and psychological processes for eliminating mental tattoos and labels. (RK)

  2. Pesticide Labeling Questions & Answers

    EPA Pesticide Factsheets

    Pesticide manufacturers, applicators, state regulatory agencies, and other stakeholders raise questions or issues about pesticide labels. The questions on this page are those that apply to multiple products or address inconsistencies among product labels.

  3. Soil Fumigant Labels - Chloropicrin

    EPA Pesticide Factsheets

    Search by EPA registration number, product name, or company name, and follow the link to the Pesticide Product Label System (PPLS) for details on each fumigant. Updated labels include new safety requirements for buffer zones and related measures.

  4. Label Review Training: Module 1: Label Basics, Page 22

    EPA Pesticide Factsheets

    This module of the pesticide label review training provides basic information about pesticides, their labeling and regulation, and the core principles of pesticide label review. Learn about what labels require review.

  5. Label Review Training: Module 1: Label Basics, Page 27

    EPA Pesticide Factsheets

    This module of the pesticide label review training provides basic information about pesticides, their labeling and regulation, and the core principles of pesticide label review. See examples of mandatory and advisory label statements.

  6. Label Review Training: Module 1: Label Basics, Page 21

    EPA Pesticide Factsheets

    This module of the pesticide label review training provides basic information about pesticides, their labeling and regulation, and the core principles of pesticide label review. Learn about types of labels.

  7. Label Review Training: Module 1: Label Basics, Page 24

    EPA Pesticide Factsheets

    This module of the pesticide label review training provides basic information about pesticides, their labeling and regulation, and the core principles of pesticide label review. This page is about which labels require review.

  8. Label Review Training: Module 1: Label Basics, Page 17

    EPA Pesticide Factsheets

    This module of the pesticide label review training provides basic information about pesticides, their labeling and regulation, and the core principles of pesticide label review. See an overview of the importance of labels.

  9. Label Review Training: Module 1: Label Basics, Page 23

    EPA Pesticide Factsheets

    This module of the pesticide label review training provides basic information about pesticides, their labeling and regulation, and the core principles of pesticide label review. Lists types of labels that do not require review.

  10. Label Review Training: Module 1: Label Basics, Page 16

    EPA Pesticide Factsheets

    This module of the pesticide label review training provides basic information about pesticides, their labeling and regulation, and the core principles of pesticide label review. Learn about the importance of labels and the role in enforcement.

  11. Label Review Training: Module 1: Label Basics, Page 15

    EPA Pesticide Factsheets

    This module of the pesticide label review training provides basic information about pesticides, their labeling and regulation, and the core principles of pesticide label review. Learn about the consequences of improper labeling.

  12. Application of Palladium-Mediated 18F-Fluorination to PET Radiotracer Development: Overcoming Hurdles to Translation

    PubMed Central

    Kamlet, Adam S.; Neumann, Constanze N.; Lee, Eunsung; Carlin, Stephen M.; Moseley, Christian K.; Stephenson, Nickeisha; Hooker, Jacob M.; Ritter, Tobias

    2013-01-01

    New chemistry methods for the synthesis of radiolabeled small molecules have the potential to impact clinical positron emission tomography (PET) imaging, if they can be successfully translated. However, progression of modern reactions from the stage of synthetic chemistry development to the preparation of radiotracer doses ready for use in human PET imaging is challenging and rare. Here we describe the process of and the successful translation of a modern palladium-mediated fluorination reaction to non-human primate (NHP) baboon PET imaging–an important milestone on the path to human PET imaging. The method, which transforms [18F]fluoride into an electrophilic fluorination reagent, provides access to aryl–18F bonds that would be challenging to synthesize via conventional radiochemistry methods. PMID:23554994

  13. Application of palladium-mediated (18)F-fluorination to PET radiotracer development: overcoming hurdles to translation.

    PubMed

    Kamlet, Adam S; Neumann, Constanze N; Lee, Eunsung; Carlin, Stephen M; Moseley, Christian K; Stephenson, Nickeisha; Hooker, Jacob M; Ritter, Tobias

    2013-01-01

    New chemistry methods for the synthesis of radiolabeled small molecules have the potential to impact clinical positron emission tomography (PET) imaging, if they can be successfully translated. However, progression of modern reactions from the stage of synthetic chemistry development to the preparation of radiotracer doses ready for use in human PET imaging is challenging and rare. Here we describe the process of and the successful translation of a modern palladium-mediated fluorination reaction to non-human primate (NHP) baboon PET imaging-an important milestone on the path to human PET imaging. The method, which transforms [(18)F]fluoride into an electrophilic fluorination reagent, provides access to aryl-(18)F bonds that would be challenging to synthesize via conventional radiochemistry methods.

  14. In situ lithium diffusion measurement in solid ionic conductors using short-lived radiotracer beam of 8Li

    NASA Astrophysics Data System (ADS)

    Ishiyama, H.; Jeong, S. C.; Watanabe, Y. X.; Hirayama, Y.; Imai, N.; Miyatake, H.; Oyaizu, M.; Osa, A.; Otokawa, Y.; Matsuda, M.; Nishio, K.; Makii, H.; Sato, T. K.; Kuwata, N.; Kawamura, J.; Nakao, A.; Ueno, H.; Kim, Y. H.; Kimura, S.; Mukai, M.

    2015-07-01

    We developed an in situ radiotracer method for diffusion studies in solids using short-lived α-emitting 8Li tracer. In the method, while implanting a pulsed 8Li beam into a solid material of interest, the α particles emitted into the implantation side of the sample surface were detected as a function of time. By changing the implantation depth and the detection angle against the sample surface according to lithium diffusivity (deep implantation and large angle with a large solid angle, or shallow implantation and small angle with a narrow solid angle), the method can be sensitive to a wide range of diffusion length ranging from micrometer scale to nanometer scale per second. The feasibility of the method was demonstrated by measuring the lithium diffusion coefficients to the order of 10-12 cm2/s in lithium ionic conductors.

  15. New insights into the dynamics of adsorption equilibria of humic matter as revealed by radiotracer studies

    NASA Astrophysics Data System (ADS)

    Lippold, Holger; Lippmann-Pipke, Johanna

    2014-05-01

    The mobility of contaminants in the subsurface hydrosphere can be governed by their interaction with aquatic humic substances, which may act as carriers. For modelling migration processes, retardation of humic molecules at mineral surfaces must be considered. There is, however, a lack of clarity concerning the reversibility of adsorption of these natural polyelectrolytes. In this work, evidence was provided that a dynamic adsorption equilibrium exists. For this purpose, adsorption of humic substances (purified Aldrich humic acid and an aquatic fulvic acid) onto kaolinite was examined in tracer exchange studies by means of 14C-labelled humic material. In addition, the kinetics of adsorption and desorption were investigated in batch experiments.

  16. Internal radiation dosimetry of orally administered radiotracers for the assessment of gastrointestinal motility.

    PubMed

    Yeong, Chai-Hong; Ng, Kwan-Hoong; Abdullah, Basri Johan Jeet; Chung, Lip-Yong; Goh, Khean-Lee; Perkins, Alan Christopher

    2014-12-01

    Radionuclide imaging using (111)In, (99m)Tc and (153)Sm is commonly undertaken for the clinical investigation of gastric emptying, intestinal motility and whole gut transit. However the documented evidence concerning internal radiation dosimetry for such studies is not readily available. This communication documents the internal radiation dosimetry for whole gastrointestinal transit studies using (111)In, (99m)Tc and (153)Sm labeled formulations. The findings were compared to the diagnostic reference levels recommended by the United Kingdom Administration of Radioactive Substances Advisory Committee, for gastrointestinal transit studies.

  17. Positron emission reconstruction tomography for the assessment of regional myocardial metabolism by the administration of substrates labeled with cyclotron produced radionuclides

    NASA Technical Reports Server (NTRS)

    Ter-Pogossian, M. M.; Hoffman, E. J.; Weiss, E. S.; Coleman, R. E.; Phelps, M. E.; Welch, M. J.; Sobel, B. E.

    1975-01-01

    A positron emission transverse tomograph device was developed which provides transaxial sectional images of the distribution of positron-emitting radionuclides in the heart. The images provide a quantitative three-dimensional map of the distribution of activity unencumbered by the superimposition of activity originating from regions overlying and underlying the plane of interest. PETT is used primarily with the cyclotron-produced radionuclides oxygen-15, nitrogen-13 and carbon-11. Because of the participation of these atoms in metabolism, they can be used to label metabolic substrates and intermediary molecules incorporated in myocardial metabolism.

  18. UV-photochemical vapor generation of selenium for atomic absorption spectrometry: Optimization and 75Se radiotracer efficiency study

    NASA Astrophysics Data System (ADS)

    Rybínová, Marcela; Musil, Stanislav; Červený, Václav; Vobecký, Miloslav; Rychlovský, Petr

    2016-09-01

    Volatile selenium compounds were generated UV-photochemically in the continuous flow mode using four UV-photoreactors differing in the material of the reaction coil; Teflon tubing and quartz tubes with various inner diameters and wall thicknesses were tested. Atomic absorption spectrometry with an externally heated quartz furnace atomizer was employed as the detector. The relevant experimental generation parameters were optimized and the basic analytical characteristics were determined. Using formic acid as the photochemical agent, limits of detection achieved for selenium were in the range 46-102 ng L- 1 in dependence on the type of UV-photoreactor employed. When nitric acid was also added to the photochemical agent, the limits of detection were reduced to 27-44 ng L- 1. The repeatability did not exceed 2.4% (5 μg L- 1 Se(IV), n = 10). Experiments with 75Se radiotracer have been performed for the first time to quantify the efficiency of UV-photochemical vapor generation (UV-PVG) of selenium. The highest efficiency of 67 ± 1% was obtained for a UV-photoreactor containing a quartz reaction coil (2.0 mm i.d., 4.0 mm o.d.). The generation efficiency of 61 ± 1% was obtained for a Teflon reaction coil (1.0 mm i.d., 1.4 mm o.d.). Mapping of the radiotracer distribution in the individual parts of the apparatus did not reveal substantial transport losses of the analyte in the UV-PVG system.

  19. Sample Pesticide Label for Label Review Training

    EPA Pesticide Factsheets

    Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human health and the environment.

  20. Pesticide Product Label System

    EPA Pesticide Factsheets

    The Pesticide Product Label System (PPLS) provides a collection of pesticide product labels (Adobe PDF format) that have been approved by EPA under Section 3 of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). New labels were added to PPLS on November 21, 2014. Pesticide product labels provide critical information about how to safely handle and use registered pesticide products. An approved pesticide product label represents the full content of EPAs registration decision regarding that product. Pesticide labels contain detailed information on the use, storage, and handling of a product. This information will be found on EPA stamped-approved labels and, in some cases, in subsequent related correspondence, which is also included in PPLS. You may need to review several PDF files for a single product to determine the complete current terms of registration.

  1. Research Projects for Interrogations of Biological Systems: Training for the Development of Novel Radiotracers

    SciTech Connect

    Jurisson, Silvia S.; Lever, Susan Z.; Robertson, J. David

    2016-10-04

    This grant was situated at the University of Missouri to train Ph.D. scientists in radiochemistry and synthetic chemistry in conjunction with Faculty from the Interdisciplinary Plant Group, Division of Biological Sciences, the MU Research Reactor Center, Molecular Biology and the Radiopharmaceutical Sciences Institute. This project was collaborative with Brookhaven National Laboratory (Richard Ferrieri, PI). Projects for the Ph.D. candidates included novel probe development for peptides, nucleosides, small molecules or radiometals, the direct use of radiometals as probes, or nuclear techniques for analysis. The projects for the postdoctoral fellow involved synthetic chemistry for the preparation of precursors for novel tracers that will be radiolabeled with 18F or other appropriate radionuclides. The skill sets of our team members allowed us to prepare probes with positron or single photon emitters, as well as ones that are dual-labeled (fluorescent and radiolabeled). We focused our technical advances to those that will be broadly applicable to any research field.

  2. Development of F-18 Labeled Radiotracers for PET Imaging of Brain Alpha-1 Noradrenergic Receptors: Potential PTSD Vulnerability and Diagnostic Biomarkers

    DTIC Science & Technology

    2012-09-01

    SERT) Dopamine: D1, D2, D3, D4, and D5 Dopamine uptake transporter (DAT) Histamine : H1, H2, and H3 Acetylcholine: M1, M2, M3, M4, and M5...Cimetidine H3 [3H]alpha-methylhistamine Histamine HISTAMINE H4 [3H] Histamine Clozapine M1 [3H]QNB Atropine M2 [3H]QNB Atropine M3...Dopamine: D1, D2, D3, D4, and D5 •Dopamine uptake transporter (DAT) • Histamine : H1, H2, and H3 •Acetylcholine: M1, M2, M3, M4, and M5 •Endogenous

  3. Quantitative immuno-positron emission tomography imaging of HER2-positive tumor xenografts with an iodine-124 labeled anti-HER2 diabody.

    PubMed

    Robinson, Matthew K; Doss, Mohan; Shaller, Calvin; Narayanan, Deepa; Marks, James D; Adler, Lee P; González Trotter, Dinko E; Adams, Gregory P

    2005-02-15

    Positron emission tomography (PET) provides an effective means of both diagnosing/staging several types of cancer and evaluating efficacy of treatment. To date, the only U.S. Food and Drug Administration-approved radiotracer for oncologic PET is (18)F-fluoro-deoxyglucose, which measures glucose accumulation as a surrogate for malignant activity. Engineered antibody fragments have been developed with the appropriate targeting specificity and systemic elimination properties predicted to allow for effective imaging of cancer based on expression of tumor associated antigens. We evaluated a small engineered antibody fragment specific for the HER2 receptor tyrosine kinase (C6.5 diabody) for its ability to function as a PET radiotracer when labeled with iodine-124. Our studies revealed HER2-dependent imaging of mouse tumor xenografts with a time-dependent increase in tumor-to-background signal over the course of the experiments. Radioiodination via an indirect method attenuated uptake of radioiodine in tissues that express the Na/I symporter without affecting the ability to image the tumor xenografts. In addition, we validated a method for using a clinical PET/computed tomography scanner to quantify tumor uptake in small-animal model systems; quantitation of the tumor targeting by PET correlated with traditional necropsy-based analysis at all time points analyzed. Thus, diabodies may represent an effective molecular structure for development of novel PET radiotracers.

  4. Improved Modeling of In Vivo Kinetics of Slowly Diffusing Radiotracers for Tumor Imaging

    PubMed Central

    Wilks, Moses Q.; Knowles, Scott M.; Wu, Anna M.; Huang, Sung-Cheng

    2015-01-01

    Large-molecule tracers, such as labeled antibodies, have shown success in immuno-PET for imaging of specific cell surface biomarkers. However, previous work has shown that localization of such tracers shows high levels of heterogeneity in target tissues, due to both the slow diffusion and the high affinity of these compounds. In this work, we investigate the effects of subvoxel spatial heterogeneity on measured time–activity curves in PET imaging and the effects of ignoring diffusion limitation on parameter estimates from kinetic modeling. Methods Partial differential equations (PDE) were built to model a radially symmetric reaction-diffusion equation describing the activity of immuno-PET tracers. The effects of slower diffusion on measured time–activity curves and parameter estimates were measured in silico, and a modified Levenberg–Marquardt algorithm with Bayesian priors was developed to accurately estimate parameters from diffusion-limited data. This algorithm was applied to immuno-PET data of mice implanted with prostate stem cell antigen–overexpressing tumors and injected with 124I-labeled A11 anti–prostate stem cell antigen minibody. Results Slow diffusion of tracers in linear binding models resulted in heterogeneous localization in silico but no measurable differences in time–activity curves. For more realistic saturable binding models, measured time–activity curves were strongly dependent on diffusion rates of the tracers. Fitting diffusion-limited data with regular compartmental models led to parameter estimate bias in an excess of 1,000% of true values, while the new model and fitting protocol could accurately measure kinetics in silico. In vivo imaging data were also fit well by the new PDE model, with estimates of the dissociation constant (Kd) and receptor density close to in vitro measurements and with order of magnitude differences from a regular compartmental model ignoring tracer diffusion limitation. Conclusion Heterogeneous

  5. Tissue biodistribution and blood clearance rates of intravenously administered carbon nanotube radiotracers

    NASA Astrophysics Data System (ADS)

    Singh, Ravi; Pantarotto, Davide; Lacerda, Lara; Pastorin, Giorgia; Klumpp, Cédric; Prato, Maurizio; Bianco, Alberto; Kostarelos, Kostas

    2006-02-01

    Carbon nanotubes (CNT) are intensively being developed for biomedical applications including drug and gene delivery. Although all possible clinical applications will require compatibility of CNT with the biological milieu, their in vivo capabilities and limitations have not yet been explored. In this work, water-soluble, single-walled CNT (SWNT) have been functionalized with the chelating molecule diethylentriaminepentaacetic (DTPA) and labeled with indium (111In) for imaging purposes. Intravenous (i.v.) administration of these functionalized SWNT (f-SWNT) followed by radioactivity tracing using gamma scintigraphy indicated that f-SWNT are not retained in any of the reticuloendothelial system organs (liver or spleen) and are rapidly cleared from systemic blood circulation through the renal excretion route. The observed rapid blood clearance and half-life (3 h) of f-SWNT has major implications for all potential clinical uses of CNT. Moreover, urine excretion studies using both f-SWNT and functionalized multiwalled CNT followed by electron microscopy analysis of urine samples revealed that both types of nanotubes were excreted as intact nanotubes. This work describes the pharmacokinetic parameters of i.v. administered functionalized CNT relevant for various therapeutic and diagnostic applications. nanomedicine | blood circulation half-life | drug delivery | pharmacokinetics | nanotoxicology

  6. Positron emission tomography (PET) imaging with 18F-based radiotracers

    PubMed Central

    Alauddin, Mian M

    2012-01-01

    Positron Emission Tomography (PET) is a nuclear medicine imaging technique that is widely used in early detection and treatment follow up of many diseases, including cancer. This modality requires positron-emitting isotope labeled biomolecules, which are synthesized prior to perform imaging studies. Fluorine-18 is one of the several isotopes of fluorine that is routinely used in radiolabeling of biomolecules for PET; because of its positron emitting property and favorable half-life of 109.8 min. The biologically active molecule most commonly used for PET is 2-deoxy-2-18F-fluoro-β-D-glucose (18F-FDG), an analogue of glucose, for early detection of tumors. The concentrations of tracer accumulation (PET image) demonstrate the metabolic activity of tissues in terms of regional glucose metabolism and accumulation. Other tracers are also used in PET to image the tissue concentration. In this review, information on fluorination and radiofluorination reactions, radiofluorinating agents, and radiolabeling of various compounds and their application in PET imaging is presented. PMID:23133802

  7. Bacterial mineralization of phenanthrene on thermally activated palygorskite: A (14)C radiotracer study.

    PubMed

    Biswas, Bhabananda; Sarkar, Binoy; Naidu, Ravi

    2017-02-01

    Clay-bacterial interaction can significantly influence the biodegradation of organic contaminants in the environment. A moderate heat treatment of palygorskite could alter the physicochemical properties of the clay mineral and thus support the growth and function of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria. By using (14)C-labelled phenanthrene and a model bacterium Burkholderia sartisoli, we studied the mineralization of phenanthrene on the surface of a moderately heat-treated (up to 400°C) palygorskite. The heat treatment at 400°C induced a reduction of binding sites (e.g., by the elimination of organic matter and/or channel shrinkage) in the palygorskite and thus imparted a weaker sequestration of phenanthrene on its surface and within the pores. As a result, a supplement with the thermally modified palygorskite (400°C) significantly increased (20-30%; p<0.05) the biomineralization of total phenanthrene in a simulated soil slurry system. These results are highly promising to develop a clay mineral based technology for the bioremediation of PAH contaminants in water and soil environments.

  8. Radiotracer study of the adsorption of organic compounds on gold. adsorption of chloroacetic and phenylacetic acid, and the effects of cadmium, copper, and silver adatoms on it

    SciTech Connect

    Horani, G.; Andreev, V.N.; Vazarinov, V.E.

    1986-04-01

    This paper studies the adsorption of monochloroacetic and phenylacetic acid (MA and PA, respectively) by the radiotracer technique on gold-plated gold electrodes in acidic solutions. The authors also study the effect of cadmium, copper, and silver adatoms on these processes. The adsorption of MA was measured as a function of potential of the electrode. Data from these measurements are presented. Data show that cadmium, copper, and silver ions present in the solution have no effect on the adsorption of PA at potentials where they are not adsorbed on the gold surface. It is confirmed that the radiotracer technique will be as effective in adsorption studies on the gold-plated gold electrode as it was in the case of the platinized platinum electrode.

  9. Voxel-based analysis of Alzheimer's disease PET imaging using a triplet of radiotracers: PIB, FDDNP, and FDG.

    PubMed

    Shin, Jonghan; Lee, Sang-Yoon; Kim, Seog Ju; Kim, So-Hee; Cho, Seong-Jin; Kim, Young-Bo

    2010-08-15

    Beta amyloid plaques, neurofibrillary tangles, and impaired glucose metabolism are among the most prevalent pathological characteristics of Alzheimer's disease (AD). However, separate visualization of these three AD-related pathologies in living humans has not been conducted. Here, we show that positron emission tomography (PET) imaging using the three radiotracers (11)C-Pittsburgh compound B (PIB), 2-(1-{6-[(2-(18)F-fluoroethyl)(methyl)amino]-2-naphthyl}ethylidene) malononitrile (FDDNP), and 2-[18F]fluoro-2-deoxy-d-glucose (FDG), in the same subjects, with and without AD, can provide valuable information on the pathological patterns of the distribution of tracers for amyloid plaque, neurofibrillary tangle, and glucose hypometabolism in AD. Voxel-based analysis of PIB-PET in patients with AD compared with normal control subjects showed that patients with AD have highly significant PIB retention in brain regions known to have high amyloid plaque deposition (e.g., frontal, parietal, temporal, and posterior cingulate/precuneus cortices). In contrast, voxel-based analysis of FDDNP-PET showed significantly high FDDNP binding in some brain regions known to have high tangle accumulation in patients with AD compared with age-matched normal subjects (e.g., entorhinal cortex, inferior temporal gyrus, and secondary visual cortex). In addition, because FDDNP binds both plaques and tangles but PIB binds plaques specifically, we examined subtracted PET data (FDDNP minus PIB) acquired from the same patients with AD using an SPM analysis. We found that the hippocampal formation was the most significant brain region in the voxel mapping of FDDNP minus PIB in the same patients with AD. Voxel-based analysis of FDG-PET in the same subjects revealed that brain regions with glucose hypometabolism in patients with AD overlap with regions of high PIB binding. In conclusion, PET imaging using these three radiotracers in the same subjects may contribute toward developing and testing disease

  10. Labeling and Delinquency.

    ERIC Educational Resources Information Center

    Adams, Mike S.; Robertson, Craig T.; Gray-Ray, Phyllis; Ray, Melvin C.

    2003-01-01

    Index comprised of six contrasting descriptive adjectives was used to measure incarcerated youths' perceived negative labeling from the perspective of parents, teachers, and peers. Results provided partial support for hypothesis that juveniles who choose a greater number of negative labels will report more frequent delinquent involvement. Labeling…

  11. In vitro and in vivo properties of (/sup 125/I) (R,S) 4IQNB: A lower affinity diastereomeric muscarinic receptor radiotracer

    SciTech Connect

    Gibson, R.E.; Schneidau, T.A.; Rzeszotarski, W.J.; Cohen, V.I.; Eckelman, W.C.; Reba, R.C.

    1985-05-01

    The (R,R) diastereomer of 3-Quinuclidinyl 4-Iodobenzilate (4IQNB) is a high affinity muscarinic acetylcholine receptor radiotracer which has provided images of receptor distribution in the CNS of man. The radiotracer is of such high affinity that dissociation in vivo is not evident in man after 6-half-lives I-123. Since the dissociation kinetics of radiotracer may be helpful for receptor quantitation, the authors have prepared (/sup 125/I) (R,S) 4IQNB: a diastereomer of 4IQNB which as a lower affinity for the m-AChR than the (R,R) isomer. The equilibrium association constant for the (R,S) diastereomer is 1.10 x 10/sup 9/ M/sup -1/, which is 4-fold lower in affinity than (/sup 3/H) (R) QNB and 2-fold lower than that of the (R,R) 4IQNB. Of more interest, the dissociation rate constant of (R,S) 4IQNB is 0.099 (+0.01)/min., 15-fold more rapid than that of the (R,R) isomer. The systemic distribution of (R,S) 4IQNB is similar to that of (R,R) 4IQNB except localization in the myocardium is 2-fold lower, reflecting the lower affinity. Nonreceptor interactions are the same since the compounds differ only as optical isomers around the carbinol chiral center. In the CNS peak activities are obtained in the corpus striatum (and other M/sub 1/-receptor rich structures) which are the same as obtained with (R,R) 4IQNB. However, no washout of (R,R) 4IQNB is observed after 4 hrs and only 60% in 24 hrs. By contrast, 65% of (R,S) 4IQNB washes out in 4 hrs and no significant activity is detected after 24 hrs. The increased washout kinetics should provide a better radiotracer for determining muscarinic receptor concentrations in the CNS of man.

  12. Radiotracer Evaluation of the Contribution of Degradation Products of Phenolic Resins to the Poisoning of Electrodes in the 190 C Hydrogen/Air Fuel Cell.

    DTIC Science & Technology

    1980-12-01

    R.F. Pascoe , H.R. Kunz, "Surface Area Loss of Platinum Supported on Carbon in Phosphoric Acid Electrolyte", J. Electrochem. Soc. 127, 1219 (1980). 4...1a. SUPPLEMENTARY NOTES IS. KEY WORDS (Contin he a reverse side It noceasm, mid Identify by block number) Fuel cells, phosphoric acid , bipolar...plates, phenolic resins, composite graphite, Carbon-14, radiotracer, electro-catalyst, electrode poisoning, platinum on carbon catalyst, acid -resistant

  13. Government perspective: food labeling.

    PubMed

    Philipson, Tomas

    2005-07-01

    The Food and Drug Administration acknowledges the severity of the obesity epidemic. The Food and Drug Administration recognizes the importance of food labeling as a vehicle for dietary messages and, thus, enforces stringent guidelines to maintain the integrity of the food label. As food labels await another upgrade to make them more effective and easier to understand, the Food and Drug Administration considers what information will be most useful for consumers to make healthy choices. The causal relationship between food labels and subsequent diet choice is not well understood; more research in this area is needed. The Commissioner of the Food and Drug Administration has recently appointed an Obesity Working Group to develop proposals on pertinent topics of obesity, including the role of food labeling as a dietary guide.

  14. Mining Multi-label Data

    NASA Astrophysics Data System (ADS)

    Tsoumakas, Grigorios; Katakis, Ioannis; Vlahavas, Ioannis

    A large body of research in supervised learning deals with the analysis of single-label data, where training examples are associated with a single label λ from a set of disjoint labels L. However, training examples in several application domains are often associated with a set of labels Y ⊆ L. Such data are called multi-label.

  15. Tracer-kinetic models for measuring cerebral blood flow using externally detected radiotracers

    SciTech Connect

    Larson, K.B.; Markham, J.; Raichle, M.E.

    1987-08-01

    All tracer-kinetic models currently employed with positron-emission tomography (PET) are based on compartmental assumptions. Our first indication that a compartmental model might suffer from severe limitations in certain circumstances when used with PET occurred when we implemented the Kety tissue-autoradiography technique for measuring CBF and observed that the resulting CBF estimates, rather than remaining constant (to within predictable statistical uncertainty) as expected, fell with increasing scan duration T when T greater than 1 min. After ruling out other explanations, we concluded that a one-compartment model does not possess sufficient realism for adequately describing the movement of labeled water in brain. This article recounts our search for more realistic substitute models. We give our derivations and results for the residue-detection impulse responses for unit capillary-tissue systems of our two candidate distributed-parameter models. In a sequence of trials beginning with the simplest, we tested four progressively more detailed candidate models against data from appropriate residue-detection experiments. In these, we generated high-temporal-resolution counting-rate data reflecting the history of radiolabeled-water uptake and washout in the brains of rhesus monkeys. We describe our treatment of the data to yield model-independent empirical values of CBF and of other parameters. By substituting these into our trial-model functions, we were able to make direct comparisons of the model predictions with the experimental dynamic counting-rate histories, confirming that our reservations concerning the one-compartment model were well founded and obliging us to reject two others. We conclude that a two-barrier distributed-parameter model has the potential of serving as a substitute for the Kety model in PET measurements of CBF in patients, especially when scan durations for T greater than 1 min are desired.

  16. Label Review Training: Module 1: Label Basics, Page 29

    EPA Pesticide Factsheets

    This module of the pesticide label review training provides basic information about pesticides, their labeling and regulation, and the core principles of pesticide label review. This page is a quiz on Module 1.

  17. Dissociation of reticuloendothelial cell and hepatocyte functions in alcoholic liver disease: a clinical study with a new Tc-99m-labeled hepatobiliary agent

    SciTech Connect

    Rao, B.K.; Weir, G.J. Jr.; Lieberman, L.M.

    1981-07-01

    Tc-99m-sulfur colloid scintigrams were abnormal in four patients with hepatic dysfunction due to chronic alcohol abuse. Minimal uptake of radiocolloid in the liver suggested local reticuloendothelial (RE) cell failure. Imaging with a new hepatobiliary agent, Tc-99m-PIPIDA, revealed rapid hepatic accumulation and excretion of radiotracer with adequate visualization of the organ. Scintigraphic findings in these patients indicated a dissociation of hepatocyte and RE cell functions. Demonstration of adequate hepatocyte function with severe RE failure in alcoholic liver disease using a Tc-99m-labeled hepatobiliary agent has not been previously reported.

  18. Radiotracer Evidence Implicating Phosphoryl and Phosphatidyl Bases as Intermediates in Betaine Synthesis by Water-Stressed Barley Leaves 12

    PubMed Central

    Hitz, William D.; Rhodes, David; Hanson, Andrew D.

    1981-01-01

    In barley, glycine betaine is a metabolic end product accumulated by wilted leaves; betaine accumulation involves acceleration of de novo synthesis from serine, via ethanolamine, N-methylethanolamines, choline, and betaine aldehyde (Hanson, Scott 1980 Plant Physiol 66: 342-348). Because in animals and microorganisms the N-methylation of ethanolamine involves phosphatide intermediates, and because in barley, wilting markedly increases the rate of methylation of ethanolamine to choline, the labeling of phosphatides was followed after supplying [14C]ethanolamine to attached leaf blades of turgid and wilted barley plants. The kinetics of labeling of phosphatidylcholine and betaine showed that phosphatidylcholine became labeled 2.5-fold faster in wilted than in turgid leaves, and that after short incubations, phosphatidylcholine was always more heavily labeled than betaine. In pulse-chase experiments with wilted leaves, label from [14C]ethanolamine continued to accumulate in betaine as it was being lost from phosphatidylcholine. When [14C]monomethylethanolamine was supplied to wilted leaves, phosphatidylcholine was initially more heavily labeled than betaine. These results are qualitatively consistent with a precursor-to-product relationship between phosphatidylcholine and betaine. The following experiments, in which tracer amounts of [14C]ethanolamine or [14C]formate were supplied to wilted barley leaves, implicated phosphoryl and phosphatidyl bases as intermediates in the methylation steps between ethanolamine and phosphatidylcholine. Label from both [14C]ethanolamine and [14C]formate entered phosphorylmonomethylethanolamine and phosphorylcholine very rapidly; these phosphoryl bases were the most heavily labeled products at 15 to 30 minutes after label addition and lost label rapidly as the fed 14C-labeled precursor was depleted. Phosphatidylmonomethylethanolamine and phosphatidylcholine were also significantly labeled from [14C]ethanolamine and [14C]formate at early

  19. Optimizing tumor targeting of the lipophilic EGFR-binding radiotracer SKI 243 using a liposomal nanoparticle delivery system.

    PubMed

    Medina, Oula Penate; Pillarsetty, Nagavarakishore; Glekas, Athanasios; Punzalan, Blesida; Longo, Valerie; Gönen, Mithat; Zanzonico, Pat; Smith-Jones, Peter; Larson, Steven M

    2011-02-10

    Positron emission tomography (PET) of epidermal growth factor receptor (EGFR) kinase-specific radiolabeled tracers could provide a means for non-invasively characterizing EGFR expression and signaling activity in patients' tumors before, during, and after therapy with EGFR inhibitors. Towards this goal, our group has developed PET tracers which irreversibly bind to EGFR. However, tumor uptake is relatively low because of both the lipophilicity of such tracers (e.g. the morpholino-[124I]-IPQA [SKI 212243]), with octanol-to-water partition coefficients of up to 4, and a short dwell time in the blood and significant hepatobiliary clearance and intestinal reuptake. Liposomal nanoparticle delivery systems may favorably alter the pharmacokinetic profile and improve tumor targeting of highly lipophilic but otherwise promising cancer imaging tracers, such as the EGFR inhibitor SKI 243. SKI 243 is therefore an interesting model molecule for incorporation into lipid-based nanoparticles, as it would not only improve their solubility but also increase the circulation time, availability and, potentially, targeting of tumors. In the current study, we compared the pharmacokinetics and tumor targeting of the bare EGFR kinase-targeting radiotracer SKI 212243 (SKI 243) with that of the same tracer embedded in liposomes. SKI 243 and liposomal SKI 243 are both taken up by tumor xenografts but liposomal SKI 243 remained in the blood longer and consequently exhibited a 3- to 6-fold increase in uptake in the tumor among several other organs.

  20. Investigation of holdup and axial dispersion of liquid phase in a catalytic exchange column using radiotracer technique.

    PubMed

    Kumar, Rajesh; Pant, H J; Goswami, Sunil; Sharma, V K; Dash, A; Mishra, S; Bhanja, K; Mohan, Sadhana; Mahajani, S M

    2017-03-01

    Holdup and axial dispersion of liquid phase in a catalytic exchange column were investigated by measuring residence time distributions (RTD) using a radiotracer technique. RTD experiments were independently carried out with two different types of packings i.e. hydrophobic water-repellent supported platinum catalyst and a mixture (50% (v/v)) of hydrophobic catalyst and a hydrophillic wettable packing were used in the column. Mean residence times and hold-ups of the liquid phase were estimated at different operating conditions. Axial dispersion model (ADM) and axial dispersion with exchange model (ADEM) were used to simulate the measured RTD data. Both the models were found equally suitable to describe the measured data. The degree of axial mixing was estimated in terms of Peclet number (Pe) and Bodenstein number (Bo). Based on the obtained parameters of the ADM, correlations for total liquid hold-up (HT) and axial mixing in terms of Bo were proposed for design and scale up of the full-scale catalytic exchange column.

  1. Off-Label Drug Use

    MedlinePlus

    ... their drugs for off-label uses. Off-label marketing is very different from off-label use. Why ... Employment Become a Supplier Report Fraud or Abuse Global Health ACS CAN Sign up for Email Policies ...

  2. Soil Fumigant Labels - Methyl Bromide

    EPA Pesticide Factsheets

    Search soil fumigant pesticide labels by EPA registration number, product name, or company, and follow the link to The Pesticide Product Label System (PPLS) for details. Updated labels include new safety requirements for buffer zones and related measures.

  3. Synthesis and biological characterisation of 18F-SIG343 and 18F-SIG353, novel and high selectivity σ2 radiotracers, for tumour imaging properties

    PubMed Central

    2013-01-01

    Background Sigma2 (σ2) receptors are highly expressed in cancer cell lines and in tumours. Two novel selective 18F-phthalimido σ2 ligands, 18F-SIG343 and 18F-SIG353, were prepared and characterised for their potential tumour imaging properties. Methods Preparation of 18F-SIG343 and 18F-SIG353 was achieved via nucleophilic substitution of their respective nitro precursors. In vitro studies including radioreceptor binding assays in the rat brain membrane and cell uptake studies in the A375 cell line were performed. In vivo studies were carried out in mice bearing A375 tumours including positron emission tomography (PET) imaging, biodistribution, blocking and metabolite studies. Results In vitro studies showed that SIG343 and SIG353 displayed excellent affinity and selectivity for σ2 receptors (Ki(σ2) = 8 and 3 nM, σ2:σ1 = 200- and 110-fold, respectively). The σ2 selectivity of 18F-SIG343 was further confirmed by blocking studies in A375 cells, however, not noted for 18F-SIG353. Biodistribution studies showed that both radiotracers had similar characteristics including moderately high tumour uptake (4%ID/g to 5%ID/g); low bone uptake (3%ID/g to 4%ID/g); and high tumour-to-muscle uptake ratios (four- to sevenfold) up to 120 min. Although radiotracer uptake in organs known to express σ receptors was significantly blocked by pre-injection of competing σ ligands, the blocking effect was not observed in the tumour. PET imaging studies indicated major radioactive localisation in the chest cavity for both ligands, with approximately 1%ID/g uptake in the tumour at 120 min. Metabolite studies showed that the original radiotracers remained unchanged 65% to 80% in the tumour up to 120 min. Conclusions The lead ligands showed promising in vitro and in vivo characteristics. However, PET imaging indicated low tumour-to-background ratios. Furthermore, we were unable to demonstrate that uptake in the A375 tumour was σ2-specific. 18F-SIG343 and 18F-SIG343 do not

  4. Capacitive label reader

    DOEpatents

    Arlowe, H.D.

    1983-07-15

    A capacitive label reader includes an outer ring transmitting portion, an inner ring transmitting portion, and a plurality of insulated receiving portions. A label is the mirror-image of the reader except that identifying portions corresponding to the receiving portions are insulated from only one of two coupling elements. Positive and negative pulses applied, respectively, to the two transmitting rings biased a CMOS shift register positively to either a 1 or 0 condition. The output of the CMOS may be read as an indication of the label.

  5. Capacitive label reader

    DOEpatents

    Arlowe, H.D.

    1985-11-12

    A capacitive label reader includes an outer ring transmitting portion, an inner ring transmitting portion, and a plurality of insulated receiving portions. A label is the mirror-image of the reader except that identifying portions corresponding to the receiving portions are insulated from only one of two coupling elements. Positive and negative pulses applied, respectively, to the two transmitting rings biased a CMOS shift register positively to either a 1 or 0 condition. The output of the CMOS may be read as an indication of the label. 5 figs.

  6. Capacitive label reader

    DOEpatents

    Arlowe, H. Duane

    1985-01-01

    A capacitive label reader includes an outer ring transmitting portion, an inner ring transmitting portion, and a plurality of insulated receiving portions. A label is the mirror-image of the reader except that identifying portions corresponding to the receiving portions are insulated from only one of two coupling elements. Positive and negative pulses applied, respectively, to the two transmitting rings biased a CMOS shift register positively to either a 1 or 0 condition. The output of the CMOS may be read as an indication of the label.

  7. Myelin imaging with C-11 labeled diphenylmethanol and positron emission tomography

    SciTech Connect

    Herscovitch, P.; Dischino, D.D.; Kilbourn, M.R.; Welch, M.J.; Raichle, M.E.

    1985-05-01

    The authors have recently studied several C-11-labeled radiopharmaceuticals for their suitability as myelin imaging agents with positron emission tomography (PET). C-11 diphenylmethanol (DPM) was selected on the basis of its in vivo metabolic stability and high extraction and lipophilicity. PET studies were performed in three normal subjects and in one patient with multiple sclerosis (MS). Myelin distribution was imaged following the bolus intravenous administration of 25-30 mCi of C-11 DPM. Sequential scans were obtained after radiotracer administration to measure the DPM distribution as a function of time. In addition, regional cerebral blood flow was measured after the bolus intravenous injection of 0-15 water. A tomographic slice through the centrum semiovale was used to obtain regional data for gray matter (GM) and white matter (WM).

  8. Figuring Out Food Labels

    MedlinePlus

    ... milk dairy products also contribute to cholesterol level. Sodium Sodium, a component of salt, is listed on the Nutrition Facts label in milligrams. Small amounts of sodium are necessary for keeping proper body fluid balance, ...

  9. Label Review Training - Resources

    EPA Pesticide Factsheets

    Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human health and the environment.

  10. Like your labels?

    PubMed

    Field, Michele

    2010-01-01

    The descriptive “conventions” used on food labels are always evolving. Today, however, the changes are so complicated (partly driven by legislation requiring disclosures about environmental impacts, health issues, and geographical provenance) that these labels more often baffle buyers than enlighten them. In a light-handed manner, the article points to how sometimes reading label language can be like deciphering runes—and how if we are familiar with the technical terms, we can find a literal meaning, but still not see the implications. The article could be ten times longer because food labels vary according to cultures—but all food-exporting cultures now take advantage of our short attention-span when faced with these texts. The question is whether less is more—and if so, in this contest for our attention, what “contestant” is voted off.

  11. Synthesis and evaluation of an (125)I-labeled azide prosthetic group for efficient and bioorthogonal radiolabeling of cyclooctyne-group containing molecules using copper-free click reaction.

    PubMed

    Choi, Mi Hee; Shim, Ha Eun; Nam, You Ree; Kim, Hye Rim; Kang, Jung Ae; Lee, Dong-Eun; Park, Sang Hyun; Choi, Dae Seong; Jang, Beom-Su; Jeon, Jongho

    2016-02-01

    Herein we report the radiosynthesis of a pyridine derived azide prosthetic group for iodine radioisotope labeling of dibenzocyclooctyne (DBCO) conjugated molecules. The radiolabeling of the stannylated precursor 2 was conducted using [(125)I]NaI and chloramine-T to give (125)I-labeled azide ([(125)I]1) with high radiochemical yield (72±8%, n=4) and radiochemical purity (>99%). Using (125)I-labeled azide ([(125)I]1), cyclic RGD peptide and near infrared fluorescent molecule were efficiently labeled with modest to good radiochemical yields. The biodistribution study and SPECT/CT images showed that [(125)I]1 underwent rapid renal clearance. These results clearly demonstrated that [(125)I]1 could be used as an useful radiotracer for in vivo pre-targeted imaging as well as efficient in vitro radiolabeling of DBCO containing molecules.

  12. Radiotracer evidence implicating phosphoryl and phosphatidyl bases as intermediates in betaine synthesis by water-stressed barley leaves

    SciTech Connect

    Hitz, W.D.; Rhodes, D.; Hanson, A.

    1981-10-01

    In pulse-chase experiments with barley wilted leaves, label from (/sup 14/C)-ethanolamine continued to accumulate in betaine as it was being lost from phosphatidylcholine. When (/sup 14/C)monomethylethanolamine was supplied to wilted leaves, phosphatidylcholine was initially more heavily labeled than betaine. These results are qualitatively consistent with a precursor-to-product relationship between phosphatidylcholine and betaine. The following experiments, in which tracer amounts of (/sup 14/C)ethanolamine or (/sup 14/C)formate were supplied to wilted barley leaves, implicated phosphoryl and phosphatidyl bases as intermediates in the methylation steps between ethanolamine and phosphatidylcholine. Label from both (/sup 14/C)ethanolamine and (/sup 14/C)formate entered phosphorylmonomethylethanolamine and phosphorylcholine very rapidly; these phosphoryl bases were the most heavily labeled products at 15 to 30 minutes after label addition and lost label rapidly as the fed /sup 14/C-labeled precursor was depleted. Phosphatidylmonomethylethanolamine and phosphatidylcholine were also significantly labeled from (/sup 14/C)ethanolamine and (/sup 14/)formate at early times; the corresponding free bases and nucleotide bases were not. Addition of a trapping pool of phosphorylcholine reduced (/sup 14/C)ethanolamine conversion to both phosphatidylcholine and betaine, and resulted in accumulation of labe in the trap. A computer model of the synthesis of betaine via phosphatidylcholine was developed from /sup 14/C kinetic data. The model indicates that about 20% of the total leaf phosphatidylcholine behaves as an intermediate in betaine biosynthesis and that a marked decrease (greater than or equal to2-fold) in the half-life of this metabolically active phosphatidylcholine fraction accompanies wilting.

  13. Improved Most-Probable-Number Method To Detect Sulfate-Reducing Bacteria with Natural Media and a Radiotracer

    PubMed Central

    Vester, Flemming; Ingvorsen, Kjeld

    1998-01-01

    A greatly improved most-probable-number (MPN) method for selective enumeration of sulfate-reducing bacteria (SRB) is described. The method is based on the use of natural media and radiolabeled sulfate (35SO42−). The natural media used consisted of anaerobically prepared sterilized sludge or sediment slurries obtained from sampling sites. The densities of SRB in sediment samples from Kysing Fjord (Denmark) and activated sludge were determined by using a normal MPN (N-MPN) method with synthetic cultivation media and a tracer MPN (T-MPN) method with natural media. The T-MPN method with natural media always yielded significantly higher (100- to 1,000-fold-higher) MPN values than the N-MPN method with synthetic media. The recovery of SRB from environmental samples was investigated by simultaneously measuring sulfate reduction rates (by a 35S-radiotracer method) and bacterial counts by using the T-MPN and N-MPN methods, respectively. When bacterial numbers estimated by the T-MPN method with natural media were used, specific sulfate reduction rates (qSO42−) of 10−14 to 10−13 mol of SO42− cell−1 day−1 were calculated, which is within the range of qSO42− values previously reported for pure cultures of SRB (10−15 to 10−14 mol of SO42− cell−1 day−1). qSO42− values calculated from N-MPN values obtained with synthetic media were several orders of magnitude higher (2 × 10−10 to 7 × 10−10 mol of SO42− cell−1 day−1), showing that viable counts of SRB were seriously underestimated when standard enumeration media were used. Our results demonstrate that the use of natural media results in significant improvements in estimates of the true numbers of SRB in environmental samples. PMID:9572939

  14. H-CRRETAWAC-OH, a Lead Structure for the Development of Radiotracer Targeting Integrin α5β1?

    PubMed Central

    Maschauer, Simone; Einsiedel, Jürgen; Eder, Iris E.; Gmeiner, Peter; Virgolini, Irene J.

    2014-01-01

    Imaging of angiogenic processes is of great interest in preclinical research as well as in clinical settings. The most commonly addressed target structure for imaging angiogenesis is the integrin αvβ3. Here we describe the synthesis and evaluation of [18F]FProp-Cys*-Arg-Arg-Glu-Thr-Ala-Trp-Ala-Cys*-OH, a radiolabelled peptide designed to selectively target the integrin α5β1. Conjugation of 4-nitrophenyl-(RS)-2-[18F]fluoropropionate provided [18F]FProp-Cys*-Arg-Arg-Glu-Thr-Ala-Trp-Ala-Cys*-OH in high radiochemical purity (>95%) and a radiochemical yield of approx. 55%. In vitro evaluation showed α5β1 binding affinity in the nanomolar range, whereas affinity to αvβ3 and αIIbβ3 was >50 μM. Cell uptake studies using human melanoma M21 (αvβ3-positive andα5β1-negative), human melanoma M21-L (αvβ3-negative and α5β1-negative), and human prostate carcinoma DU145 (αvβ3-negative and α5β1-positive) confirmed receptor-specific binding. The radiotracer was stable in human serum and showed low protein binding. Biodistribution studies showed tumour uptake ranging from 2.5 to 3.5% ID/g between 30 and 120 min post-injection. However, blocking studies and studies using mice bearing α5β1-negative M21 tumours did not confirm receptor-specific uptake of [18F]FProp-Cys*-Arg-Arg-Glu-Thr-Ala-Trp-Ala-Cys*-OH, although this radiopeptide revealed high affinity and substantial selectivity to α5β1 in vitro. Further experiments are needed to study the in vivo metabolism of this peptide and to develop improved radiopeptide candidates suitable for PET imaging of α5β1 expression in vivo. PMID:25374888

  15. 2'[(18)F]-fluoroethylrhodamine B is a promising radiotracer to measure P-glycoprotein function.

    PubMed

    Trencsényi, György; Kertész, István; Krasznai, Zoárd T; Máté, Gábor; Szalóki, Gábor; Szabó Judit, P; Kárpáti, Levente; Krasznai, Zoltán; Márián, Teréz; Goda, Katalin

    2015-07-10

    In vivo detection of the emergence of P-glycoprotein (Pgp) mediated multidrug resistance in tumors could be beneficial for patients treated with anticancer drugs. PET technique in combination with appropriate radiotracers could be the most convenient method for detection of Pgp function. Rhodamine derivatives are validated fluorescent probes for measurement of mitochondrial membrane potential and also Pgp function. The aim of this study was to investigate whether 2'[(18)F]-fluoroethylrhodamine B ((18)FRB) a halogenated rhodamine derivative previously synthesized for PET assessment of myocardial perfusion preserved its Pgp substrate character. ATPase assay as well as accumulation experiments carried out using Pgp(+) and Pgp(-) human gynecologic (A2780/A2780(AD) and KB-3-1/KB-V1) and a mouse fibroblast cell pairs (NIH 3T3 and NIH 3T3 MDR1) were applied to study the interaction of (18)FRB with Pgp. ATPase assay proved that (18)FRB is a high affinity substrate of Pgp. Pgp(-) cells accumulated the (18)FRB rapidly in accordance with its lipophilic character. Dissipation of the mitochondrial proton gradient by a proton ionophore CCCP decreased the accumulation of rhodamine 123 (R123) and (18)FRB into Pgp(-) cells. Pgp(+) cells exhibited very low R123 and (18)FRB accumulation (around 1-8% of the Pgp(-) cell lines) which was not sensitive to the mitochondrial proton gradient; rather it was increased by the Pgp inhibitor cyclosporine A (CsA). Based on the above data we conclude that (18)FRB is a high affinity Pgp substrate and consequently a potential PET tracer to detect multidrug resistant tumors as well as the function of physiological barriers expressing Pgp.

  16. Metabolite identification of a radiotracer by electrochemistry coupled to liquid chromatography with mass spectrometric and radioactivity detection.

    PubMed

    Baumann, Anne; Faust, Andreas; Law, Marylin P; Kuhlmann, Michael T; Kopka, Klaus; Schäfers, Michael; Karst, Uwe

    2011-07-01

    Radioligands, which specifically bind to a receptor or enzyme (target), enable molecular imaging of the target expression by positron emission tomography (PET). One very promising PET tracer is (S)-1-(4-(2-[(18)F]-fluoroethoxy)benzyl)-5-[1-(2-methoxymethylpyrrolidinyl)sulfonyl]isatin (isatin), a caspase-3 inhibitor, which has been developed at the University Hospital of Münster to image cell death (apoptosis). The translation of this novel tracer from preclinical evaluation to clinical examinations requires biodistribution studies, which characterize the pharmakodynamics and metabolic fate of the compound. This information is used to further optimize the radioligands and to interpret radioactive signals from tissues upon injection of the radioligand in vivo with respect to their specificity. The analysis of the metabolism of radioligands is hampered by the low amount of the compound being typically injected (nano/picomolar amount per injection). In the present study, electrochemistry (EC) is applied to elucidate the oxidative metabolism pathway of the radiotracer. Previous studies have demonstrated that EC can be utilized as a complementary tool to conventional in vitro approaches in drug metabolism studies. Thereby, potential oxidative metabolites of the isatin are determined by EC coupled to electrospray ionization mass spectrometry (EC/ESI-MS). Moreover, using EC/liquid chromatography (LC) and ESI-ion trap MS(n), structural elucidation of the oxidation products is performed. Comparatively to EC, in vitro metabolism studies with rat liver microsomes are conducted. Finally, the developed LC/ESI-MS method is applied to determine metabolites in body fluids and cell extracts from in vivo studies with the nonradioactive ((19)F) and radioactive isatin ((18)F). On the basis of the electrochemically generated oxidation products of the radioligand, the major radioactive metabolite occurring in vivo was successfully identified.

  17. Radiosynthesis of N-(4-chloro-3-[11C]methoxyphenyl)-2-picolinamide ([11C]ML128) as a PET radiotracer for metabotropic glutamate receptor subtype 4 (mGlu4)

    PubMed Central

    Kil, Kun-Eek; Zhang, Zhaoda; Jokivarsi, Kimmo; Gong, Chunyu; Choi, Ji-Kyung; Kura, Sreekanth; Brownell, Anna-Liisa

    2013-01-01

    N-(Chloro-3-methoxyphenyl)-2-picolinamide (3, ML128, VU0361737) is an mGlu4 positive allosteric modulator (PAM), which is potent and centrally penetrating. 3 is also the first mGlu4 PAM to show efficacy in a preclinical Parkinson disease model upon systemic dosing. As a noninvasive medical imaging technique and a powerful tool in neurological research, positron emission tomography (PET) offers a possibility to investigate mGlu4 expression in vivo under physiologic and pathological conditions. We synthesized a carbon-11 labeled ML128 ([11C]3) as a PET radiotracer for mGlu4, and characterized its biological properties in Sprague Dawley rats. [11C]3 was synthesized from N-(4-chloro-3-hydroxyphenyl)-2-picolinamide (2) using [11C]CH3I. Total synthesis time was 38±2.2 min (n = 7) from the end of bombardment to the formulation. The radioligand [11C]3 was obtained in 27.7±5.3% (n = 5) decay corrected radiochemical yield based on the radioactivity of [11C]CO2. The radiochemical purity of [11C]3 was >99%. Specific activity was 188.7±88.8 GBq/μmol (n = 4) at the end of synthesis (EOS). PET images were conducted in 20 normal male Sprague Dawley rats including 11 control studies, 6 studies blocking with an mGlu4 modulator (4) to investigate specificity and 3 studies blocking with an mGlu5 modulator (MTEP) to investigate selectivity. These studies showed fast accumulation of [11C]3 (peak activity between 1-3 min) in several brain areas including striatum, thalamus, hippocampus, cerebellum, and olfactory bulb following with fast washout. Blocking studies with the mGlu4 modulator 4 showed 22-28 % decrease of [11C]3 accumulation while studies of selectivity showed only minor decrease supporting good selectivity over mGlu5. Biodistribution studies and blood analyses support fast metabolism. Altogether this is the first PET imaging ligand for mGlu4, in which the labeled ML128 was used for imaging its in vivo distribution and pharmacokinetics in brain. PMID:23978356

  18. Expedited Synthesis of Fluorine-18 Labeled Phenols. A Missing Link in PET Radiochemistry

    SciTech Connect

    Katzenellenbogen, John A.; Zhou, Dong

    2015-03-26

    (diazocyclohexenones) by a novel reaction sequence that uses fluoride ion as a precursor and various activating electrophiles, and we have improved methods for the preparation of heterodiaryl iodonium salts. Both methods have been used to prepare interesting potential radiotracers. Other advances have been made in labeling dendrimeric nanoparticle structures of increasing interest for multimodal imaging and in advancing labeling through fluorosilane bonds. Thus, the progress we have made substantially fills the significant gap in PET radiochemistry that we originally identified, and it provides for the field new methodology that can be applied to a number of current challenges, including the preparation of several molecules of interest as radiotracers, such as 2-[18F]Fluoroestradiol (2-FES) and m-fluorotyrosine, which we have illustrated. These methods can be used by any skilled radiochemist interesting in preparing these agents or similar fluorine-18 labeled electron-rich arene systems of interested for PET biological imaging in the most general sense.

  19. 16 CFR 305.17 - Television labeling.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... manufacturer may include the ENERGY STAR logo on the label as illustrated in Sample Labels 10, 11, and 12 in... labeled may add the ENERGY STAR logo to those labels. (g) Distribution of labels. For each...

  20. Evaluation of the influence of the conjugation site of the chelator agent HYNIC to GLP1 antagonist radiotracer for insulinoma diagnosis.

    PubMed

    Faintuch, Bluma Linkowski; Seo, Daniele; Oliveira, Érica Aparecida De; Targino, Roselaine Campos; Moro, Ana Maria

    2017-01-26

    Radiotracer diagnosis of insulinoma, can be done using somatostatin or glucagon-like peptide 1 (GLP-1). Performance of GLP-1 antagonists tends to be better than of agonists. We investigated the uptake of the antagonist exendin (9-39), radiolabeled with technetium-99m. Two different sites of the biomolecule were selected for chelator attachment. HYNIC-βAla chelator attached to serine (C- terminus) of exendin, was associated with higher tumor uptake than to aspartate (N- terminus). In conclusion the chelator position in the biomolecule influenced receptor uptake.

  1. Radiosynthesis and Evaluation of an 18F-Labeled Positron Emission Tomography (PET) Radioligand for Metabotropic Glutamate Receptor Subtype 4 (mGlu4)

    PubMed Central

    2015-01-01

    Four 4-phthalimide derivatives of N-(3-chlorophenyl)-2-picolinamide were synthesized as potential ligands for the PET imaging of mGlu4 in the brain. Of these compounds, N-(3-chloro-4-(4-fluoro-1,3-dioxoisoindolin-2-yl)phenyl)-2-picolinamide (3, KALB001) exhibited improved binding affinity (IC50 = 5.1 nM) compared with ML128 (1) and was subsequently labeled with 18F. When finally formulated in 0.1 M citrate buffer (pH 4) with 10% ethanol, the specific activity of [18F]3 at the end of synthesis (EOS) was 233.5 ± 177.8 GBq/μmol (n = 4). The radiochemical yield of [18F]3 was 16.4 ± 4.8% (n = 4), and the purity was over 98%. In vivo imaging studies in a monkey showed that the radiotracer quickly penetrated the brain with the highest accumulation in the brain areas known to express mGlu4. Despite some unfavorable radiotracer properties like fast washout in rodent studies, [18F]3 is the first 18F-labeled mGlu4 radioligand, which can be further modified to improve pharmacokinetics and brain penetrability for future human studies. PMID:25330258

  2. A Deceiving Label?

    ERIC Educational Resources Information Center

    Lum, Lydia

    2009-01-01

    The author reports on the growing debate among educators on whether the umbrella Asian Pacific Islander label conceals disparities among Asian American students or provides political power in numbers. Nationally, experts say that support services aimed at not only Southeast Asians, but all Asian Pacific Islander students, remain scarce in higher…

  3. Pharmacokinetic evaluation of the tau PET radiotracer 18F-T807 (18F-AV-1451) in human subjects

    PubMed Central

    Wooten, Dustin W.; Guehl, Nicolas J.; Verwer, Eline E.; Shoup, Timothy M.; Yokell, Daniel L.; Zubcevik, Nevena; Vasdev, Neil; Zafonte, Ross D.; Johnson, Keith A.; Fakhri, Georges El; Normandin, Marc D.

    2017-01-01

    18F-T807 is a PET radiotracer developed for imaging tau protein aggregates, which are implicated in neurological disorders including Alzheimer's disease (AD) and traumatic brain injury (TBI). The current study characterizes 18F-T807 pharmacokinetics in human subjects using dynamic PET imaging and metabolite-corrected arterial input functions. Methods Nine subjects (4 control, 3 with history of TBI, 2 mild cognitive impairment (MCI) due to suspected AD) underwent dynamic PET imaging for up to 120 minutes after bolus injection of 18F-T807 with arterial blood sampling. Total volume of distribution (VT) was estimated using compartmental modeling (one- and two-tissue configurations) and graphical analysis techniques (Logan and MA1 regression methods). Reference region-based methods of quantification were explored including Logan distribution volume ratio (DVR) and static standardized uptake value ratio (SUVR) utilizing the cerebellum as a reference tissue. Results Percent unmetabolized 18F-T807 in plasma followed a single exponential with T1/2 of 17.0±4.2 minutes. Metabolite corrected plasma radioactivity concentration fit a bi-exponential (T1/2: 18.1±5.8; 2.4±0.5 minutes). 18F-T807 in gray matter peaked quickly (SUV >2 at ∼5 minutes). Compartmental modeling resulted in good fits and the two-tissue model with estimated blood volume correction (2Tv) performed best, particularly in regions with elevated binding. VT was greater in MCI subjects than controls in the occipital, parietal, and temporal cortices as well as the posterior cingulate gyrus, precuneus, and mesial temporal cortex. High focal uptake was found in the posterior corpus callosum of a TBI subject. Plots from Logan and MA1 graphical methods became linear by 30 minutes, yielding regional estimates of VT in excellent agreement with compartmental analysis and providing high quality parametric maps when applied in voxelwise fashion. Reference region based approaches including Logan DVR (t*=55 min) and SUVR

  4. [{sup 11}C]d-threo-Methylphenidate, a new radiotracer for the dopamine transporter. Characterization in baboon and human brain

    SciTech Connect

    Ding, Y.S.; Volkow, N.D.; Fowler, J.S.

    1995-05-01

    dl-threo Methylphenidate (MP, Ritalin) is a psychostimulant drug which binds to the dopamine transporter (DAT). We evaluated [{sup 11}C]d-threo-methylphenidate ([{sup 11}C]d-MP), the more active enantiomer, as a radiotracer for the DAT in baboons and human brain. Stereoselectivity, saturability and pharmacological specificity and reproducibility were examined. Stereoselectivity was examined in baboons by comparing [{sup 11C}]d-MP,[{sup 11}C]l-MP and [{sup 11}C]dl-MP. Unlabeled MP was used to assess the reversibility and saturability of the binding. GBR 12909,{beta}-(4-iodophenyl)tropane-2-carboxylic acid methyl ester ({beta}-CIT), tomoxetine and citalopram were used to assess the specificity of the binding. The ratios between the radioactivity in the striatum to that in cerebellum (ST/CB) were 3.3,2.2 and 1.1 for [{sup 11}C]d-MP,[{sup 11}C]dl-MP and [{sup 11}C]l-MP respectively. Most of the striatal binding of [{sup 11}C]d-threo-MP was displaced by injection of nonradioactive MP demonstrating reversibility. Pretreatment with MP (0.5 mg/kg), GBR12909 (1.5 mg/kg) or {beta}-CIT (0.3 mg/kg) reduced ST/CB by about 60% and the ratios of distribution volumes at the steady-state for the triatum to cerebellum (DV{sub st/}DV{sub cb}) by about 50%. Pretreatment with tomoxetine (3.0 mg/kg) or citalopram (2.0 mg/kg), inhibitors of the norepinephrine and serotonin transporter, had no effect. Studies of [{sup 11}C]d-MP in the human brain showed highest uptake in basal ganglia with a half clearance time of about 60 minutes. Repeated studies in 6 normal human subjects showed differences in DV{sub st/}DV{sub cb} between -7% and 8%. MP pretreatment decreased BG but no cortical or cerebellar binding and reduced Bmax/Kd by 91%.

  5. Synthesis and Evaluation of [11C]LY2795050 as a Novel Kappa Opioid Receptor Antagonist Radiotracer for PET Imaging

    PubMed Central

    Zheng, Ming-Qiang; Nabulsi, Nabeel; Kim, Su Jin; Tomasi, Giampaolo; Lin, Shu-fei; Mitch, Charles; Quimby, Steven; Barth, Vanessa; Rash, Karen; Masters, John; Navarro, Antonio; Seest, Eric; Morris, Evan E.; Carson, Richard E.; Huang, Yiyun

    2013-01-01

    is a suitable ligand for imaging the KOR in primates. This newly developed KOR antagonist tracer has since been advanced to PET imaging of KOR in humans and constitutes the first successful KOR antagonist radiotracer. PMID:23353688

  6. Label Review Training: Module 1: Label Basics, Page 7

    EPA Pesticide Factsheets

    Page 7, Label Training, Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human he

  7. Ibuprofen induces reduction of the proliferation-seeking radiotracer 99mTc-(V)DMSA uptake in severe epithelial breast hyperplasia without atypia.

    PubMed

    Papantoniou, Vassilios; Tsaroucha, Angeliki; Valsamaki, Pipitsa; Tsiouris, Spyridon; Sotiropoulou, Evangelia; Karianos, Theodore; Marinopoulos, Spyridon; Fothiadaki, Athina; Sotiropoulou, Maria; Archontaki, Aikaterini; Syrgiannis, Konstantinos; Dimitrakakis, Konstantinos; Antsaklis, Aris

    2010-10-01

    The purpose of this study was to investigate if ibuprofen intake can influence mammary uptake of the proliferation-seeking radiotracer technetium 99m-pentavalent dimercaptosuccinic acid (99mTc-(V)DMSA) in women with severe epithelial and atypical epithelial breast hyperplasia. Eight patients with histologically confirmed severe epithelial breast hyperplasia with (n  =  4) and without atypia (n  =  4) were submitted prospectively to 99mTc-(V)DMSA scintimammography before and after a 4-week course of 400 mg ibuprofen daily oral intake. Lesion to background ratios 60 minutes postinjection were calculated and compared (t-test) before and after ibuprofen administration. Prior to ibuprofen, the patients with severe epithelial hyperplasia displayed a significantly higher 99mTc-(V)DMSA uptake ratio compared to those with atypical epithelial hyperplasia (2.40 ± 0.32 vs 1.67 ± 0.09, respectively; p  =  .003). They also exhibited a more substantial percent decline in tracer uptake postibuprofen compared to women with atypical epithelial hyperplasia (62.0 ± 7.1 vs 15.0 ± 0.2, respectively; p  =  .001). Ibuprofen induces significant uptake reduction of the proliferation-seeking radiotracer 99mTc-(V)DMSA in severe epithelial breast hyperplasia without atypia. This agent could therefore constitute a potential imaging tool for monitoring chemoprophylaxis effectiveness in women at the early stages of malignant transformation.

  8. Decode the Sodium Label Lingo

    MedlinePlus

    ... For Preschooler For Gradeschooler For Teen Decode the Sodium Label Lingo Published January 24, 2013 Print Email Reading food labels can help you slash sodium. Here's how to decipher them. "Sodium free" or " ...

  9. Use the Nutrition Facts Label

    MedlinePlus

    ... Features Spokespeople News Archive eNewsletters Calendar Use the Nutrition Facts Label You can help your family eat ... to some of their favorite foods. Use the Nutrition Facts label found on food packages to make ...

  10. Efficient method for iodine radioisotope labeling of cyclooctyne-containing molecules using strain-promoted copper-free click reaction.

    PubMed

    Jeon, Jongho; Kang, Jung Ae; Shim, Ha Eun; Nam, You Ree; Yoon, Seonhye; Kim, Hye Rim; Lee, Dong Eun; Park, Sang Hyun

    2015-07-01

    Herein we report an efficient method for iodine radioisotope labeling of cyclooctyne-containing molecules using copper-free click reaction. For this study, radioiodination using the tin precursor 2 was carried out at room temperature to give (125)I-labeled azide ([(125)I]1) with high radiochemical yield (85%) and excellent radiochemical purity. Dibenzocyclooctyne (DBCO) containing cRGD peptide and gold nanoparticle were labeled with [(125)I]1 at 37°C for 30min to give triazoles with good radiochemical yields (67-95%). We next carried out tissue biodistribution study of [(125)I]1 in normal ICR mice to investigate the level of organ accumulation which needs to be considered for pre-targeted in vivo imaging. Large amount of [(125)I]1 distributed rapidly in liver and kidney from bloodstream and underwent rapid renal and hepatobiliary clearance. Moreover [(125)I]1 was found to be highly stable (>92%) in mouse serum for 24h. Therefore [(125)I]1 could be used as a potentially useful radiotracer for pre-targeted imaging. Those results clearly indicated that the present radiolabeling method using copper free click reaction would be quite useful for both in vitro and in vivo labeling of DBCO group containing molecules with iodine radioisotopes.

  11. Comparison of technetium-99m sulfur colloid and technetium-99m albumin colloid labeled solid meals for gastric emptying studies.

    PubMed

    Taillefer, R; Douesnard, J M; Beauchamp, G; Guimond, J

    1987-08-01

    A Tc-99m albumin colloid (Tc-AC) kit has been introduced as an alternative to Tc-99m sulfur colloid (Tc-SC) for liver-spleen imaging. Since there is no need for boiling, the use of Tc-AC reduces preparation time and manipulation. Tc-SC is one of the most commonly used radiopharmaceuticals for the labeling of solid-phase markers in gastric emptying studies. In vitro studies were performed to evaluate the labeling efficiency and stability in hydrochloric acid and in human gastric juice of intracellularly labeled chicken liver and scrambled eggs labeled with Tc-SC and Tc-AC. Gastric emptying studies also were performed on 20 healthy volunteers with both Tc-SC and Tc-AC labeled scrambled egg sandwiches. There was no significant difference between Tc-SC and Tc-AC in the labeling efficiency of chicken liver (98% +/- 1% for Tc-SC, 96% +/- 2% for Tc-AC) and scrambled eggs (92% +/- 2% for Tc-SC, 91% +/- 3% for Tc-AC). However, both Tc-SC and Tc-AC labeled scrambled eggs showed a lower stability than chicken liver, particularly in human gastric juice. Gastric emptying curves from both meals in 20 normal subjects were also similar, with a mean half-emptying time of 85 +/- 13 minutes and 87 +/- 16 minutes for the meals containing Tc-SC and Tc-AC respectively. Tc-AC is a reliable alternative to Tc-SC as a radiotracer for solid-phase gastric emptying studies.

  12. Pathway of ammonium assimilation in a marine diatom determined with the radiotracer sup 13 N. [Thalassiosira pseudonoana (Hustedt)

    SciTech Connect

    Zehr, J.P. ); Falkowski, P.G. )

    1988-12-01

    In unicellular algae, ammonium can be assimilated into glutamate through the action of glutamate dehydrogenase (GDH) or into glutamine through the sequential activities of glutamine synthetase and glutamate 2-oxoglutarate amidotransferase (GS-GOGAT pathway). We have shown that the first radio-labeled product of assimilation of {sup 13}NH{sub 4}{sup +} (t{sub {1/2}} = 10 min) was glutamine in the marine diatom Thalassiosira pseudonana (Hustedt). When GS-GOGAT was inhibited with methionine sulfoximine, the incorporation of radioactivity into both glutamine and glutamate was blocked, implying that the radiolabeled glutamate is formed from glutamine. Glutamine was also the first labeled product when the intracellular concentration of ammonium was elevated by preincubation with unlabeled ammonium. The results indicate that the GS-GOGAT pathway is the primary pathway for the assimilation of nitrogen in T. pseudonana.

  13. Automated synthesis and dosimetry of 6-deoxy-6-[18F]fluoro-D-fructose (6-[18F]FDF): a radiotracer for imaging of GLUT5 in breast cancer

    PubMed Central

    Bouvet, Vincent; Jans, Hans S; Wuest, Melinda; Soueidan, Olivier-Mohamad; Mercer, John; McEwan, Alexander JB; West, Frederick G; Cheeseman, Chris I; Wuest, Frank

    2014-01-01

    6-Deoxy-6-[18F]fluoro-D-fructose (6-[18F]FDF) is a promising PET radiotracer for imaging GLUT5 in breast cancer. The present work describes GMP synthesis of 6-[18F]FDF in an automated synthesis unit (ASU) and dosimetry calculations to determine radiation doses in humans. GMP synthesis and dosimetry calculations are important prerequisites for first-in-human clinical studies of 6-[18F]FDF. The radiochemical synthesis of 6-[18F]FDF was optimized and adapted to an automated synthesis process using a Tracerlab FXFN ASU (GE Healthcare). Starting from 30 GBq of cyclotron-produced n.c.a. [18F]fluoride, 2.9 ± 0.1 GBq of 6-[18F]FDF could be prepared within 50 min including HPLC purification resulting in an overall decay-corrected radiochemical yield of 14 ± 3% (n = 11). Radiochemical purity exceeded 95%, and the specific activity was greater than 5.1 GBq/μmol. Sprague-Dawley rats were used for biodistribution experiments, and dynamic and static small animal PET experiments. Biodistribution studies served as basis for allometric extrapolation to the standard man anatomic model and normal organ-absorbed dose calculations using OLINDA/EXM software. The calculated human effective dose for 6-[18F]FDF was 0.0089 mSv/MBq. Highest organ doses with a dose equivalent of 0.0315 mSv/MBq in a humans were found in bone. Injection of 370 MBq (10 mCi) of 6-[18F]FDF results in an effective whole body radiation dose of 3.3 mSv in humans, a value comparable to that of other 18F-labeled PET radiopharmaceuticals. The optimized automated synthesis under GMP conditions, the good radiochemical yield and the favorable human radiation dosimetry estimates support application of 6-[18F]FDF in clinical trials for molecular imaging of GLUT5 in breast cancer patients. PMID:24795839

  14. Learning with imperfectly labeled patterns

    NASA Technical Reports Server (NTRS)

    Chittineni, C. B.

    1979-01-01

    The problem of learning in pattern recognition using imperfectly labeled patterns is considered. The performance of the Bayes and nearest neighbor classifiers with imperfect labels is discussed using a probabilistic model for the mislabeling of the training patterns. Schemes for training the classifier using both parametric and non parametric techniques are presented. Methods for the correction of imperfect labels were developed. To gain an understanding of the learning process, expressions are derived for success probability as a function of training time for a one dimensional increment error correction classifier with imperfect labels. Feature selection with imperfectly labeled patterns is described.

  15. In vivo imaging of insulin receptors by PET: preclinical evaluation of iodine-125 and iodine-124 labelled human insulin.

    PubMed

    Iozzo, P; Osman, S; Glaser, M; Knickmeier, M; Ferrannini, E; Pike, V W; Camici, P G; Law, M P

    2002-01-01

    [A(14)-*I]iodoinsulin was prepared for studies to assess the suitability of labeled iodoinsulin for positron emission tomography (PET). Iodine-125 was used to establish the methods and for preliminary studies in rats. Further studies and PET scanning in rats were carried out using iodine-124. Tissue and plasma radioactivity was measured as the uptake index (UI = [cpm x (g tissue)(-1)]/[cpm injected x (g body weight)(-1)]) at 1 to 40 min after intravenous injection of either [A(14)-(125)I]iodoinsulin or [A(14)-(124)I]iodoinsulin. For both radiotracers, initial clearance of radioactivity from plasma was rapid (T(1/2) approximately 1 min), reaching a plateau (UI = 2.8) at approximately 5 min which was maintained for 35 min. Tissue biodistributions of the two radiotracers were comparable; at 10 min after injection, UI for myocardium was 2.4, liver, 4.0, pancreas, 5.4, brain, 0.17, kidney, 22, lung, 2.3, muscle, 0.54 and fat, 0.28. Predosing rats with unlabelled insulin reduced the UI for myocardium (0.95), liver (1.8), pancreas (1.2) and brain (0.08), increased that for kidney (61) but had no effect on that for lung (2.5), muscle (0.50) or fat (0.34). Analysis of radioactivity in plasma demonstrated a decrease of [(125)I]iodoinsulin associated with the appearance of labeled metabolites; the percentage of plasma radioactivity due to [(125)I]iodoinsulin was 40% at 5 min and 10% at 10 min. The heart, liver and kidneys were visualized using [(124)I]iodoinsulin with PET.

  16. Metabolic imaging with gallium-68- and indium-111-labeled low-density lipoprotein

    SciTech Connect

    Moerlein, S.M.; Daugherty, A.; Sobel, B.E.; Welch, M.J. )

    1991-02-01

    Low-density lipoprotein (LDL) labeled with either gallium-68 ({sup 68}Ga) or indium-111 ({sup 111}In) was evaluated as a potential PET or SPECT radiopharmaceutical for determination of hepatic lipoprotein metabolism in rabbits. Gallium-68 or {sup 111}In was linked to LDL via diethylenetriaminepentaacetic acid (DTPA) with a 25-70% radiochemical yield. Studies in vivo that compared {sup 68}Ga- or {sup 111}In-DTPA-LDL with dilactitol-({sup 125}I)-tyramine LDL and 131I-LDL showed that both {sup 68}Ga- and {sup 111}In-labeled LDL behaved as residualizing radiotracers. Localization of radioactivity within the liver of normal rabbits was visualized clearly with ({sup 68}Ga)DTPA-LDL by PET and with ({sup 111}In)DTPA-LDL by gamma scintigraphy. Significant differences were observed in hepatic uptake of normal compared with hypercholesterolemic rabbits in which low-capacity LDL receptor-mediated catabolism was saturated. Gallium-68 and {sup 111}In-DTPA-LDL are attractive radiopharmaceuticals for noninvasive delineation of tissue LDL metabolism under normal and pathophysiologic conditions.

  17. Supplementing national menu labeling.

    PubMed

    Hodge, James G; White, Lexi C

    2012-12-01

    The US Food and Drug Administration's forthcoming national menu labeling regulations are designed to help curb the national obesity epidemic by requiring calorie counts on restaurants' menus. However, posted calories can be easily ignored or misunderstood by consumers and fail to accurately describe the healthiness of foods. We propose supplemental models that include nutritional information (e.g., fat, salt, sugar) or specific guidance (e.g., "heart-healthy" graphics). The goal is to empower restaurant patrons with better data to make healthier choices, and ultimately to reduce obesity prevalence.

  18. Comparison of cerebral blood flow measurement with [15O]-water positron emission tomography and arterial spin labeling magnetic resonance imaging: A systematic review.

    PubMed

    Fan, Audrey P; Jahanian, Hesamoddin; Holdsworth, Samantha J; Zaharchuk, Greg

    2016-05-01

    Noninvasive imaging of cerebral blood flow provides critical information to understand normal brain physiology as well as to identify and manage patients with neurological disorders. To date, the reference standard for cerebral blood flow measurements is considered to be positron emission tomography using injection of the [(15)O]-water radiotracer. Although [(15)O]-water has been used to study brain perfusion under normal and pathological conditions, it is not widely used in clinical settings due to the need for an on-site cyclotron, the invasive nature of arterial blood sampling, and experimental complexity. As an alternative, arterial spin labeling is a promising magnetic resonance imaging technique that magnetically labels arterial blood as it flows into the brain to map cerebral blood flow. As arterial spin labeling becomes more widely adopted in research and clinical settings, efforts have sought to standardize the method and validate its cerebral blood flow values against positron emission tomography-based cerebral blood flow measurements. The purpose of this work is to critically review studies that performed both [(15)O]-water positron emission tomography and arterial spin labeling to measure brain perfusion, with the aim of better understanding the accuracy and reproducibility of arterial spin labeling relative to the positron emission tomography reference standard.

  19. [18F]- and [11C]-Labeled N-benzyl-isatin sulfonamide analogues as PET tracers for apoptosis: synthesis, radiolabeling mechanism, and in vivo imaging of apoptosis in Fas-treated mice

    PubMed Central

    Zhou, Dong; Chu, Wenhua; Chen, Delphine L.; Wang, Qi; Reichert, David E.; Rothfuss, Justin; D'Avignon, Andre; Welch, Michael J.; Mach, Robert H.

    2011-01-01

    Summary The radiolabeled isatin sulfonamide caspase-3 inhibitor, [18F]2 (WC-II-89), is a potential PET radiotracer for noninvasive imaging of apoptosis. The radiolabeling mechanism was studied by 13C NMR, ESI/MS, and computational calculations. It was found that the high electrophilicity of the C3 carbonyl group in the isatin ring, which served as a trap for [18F]fluoride, was responsible for the failure of the radiolabeling via nucleophilic substitution of the mesylate group in 7a by [18F]fluoride. Once treated with a strong base, 7a opened the isatin ring completely to form an isatinate intermediate 16, which lost the ability to trap [18F]fluoride, thereby allowing the displacement of the mesylate group to afford the 18F-labeled isatinate 17. [18F]17 can be converted to isatin [18F]2 efficiently under acidic conditions. The ring-opening and re-closure of the isatin ring under basic and acidic conditions were confirmed by reversed phase HPLC analysis, ESI/MS and 13C NMR studies. Computational studies of model compounds also support the above proposed mechanism. Similarly, the ring-opening and re-closure method was used successfully in the synthesis of the 11C labeled isatin sulfonamide analogue [11C]4 (WC-98). A microPET imaging study using [11C]4 in the Fas liver apoptosis model demonstrated retained activity in the target organ (liver) of the treated mice. Increased caspase-3 activation in the liver was verified by the fluorometric caspase-3 enzyme assay. Therefore, this study provides a useful method for radio-synthesis of isatin derivative radiotracers for PET and SPECT studies, and [11C]4 is a potential PET radiotracer for noninvasive imaging of apoptosis. PMID:19300818

  20. Synthesis and biological evaluation of positron emission tomography radiotracers targeting serotonin 4 receptors in brain: [18F]MNI-698 and [18F]MNI-699.

    PubMed

    Caillé, Fabien; Morley, Thomas J; Tavares, Adriana Alexandre S; Papin, Caroline; Twardy, Nicole M; Alagille, David; Lee, H Sharon; Baldwin, Ronald M; Seibyl, John P; Barret, Olivier; Tamagnan, Gilles D

    2013-12-01

    Two new benzodioxane derivatives were synthesized as candidates to image the serotonin 4 receptors by positron emission tomography (PET) and radiolabeled with fluorine-18 via a two-step procedure. Competition binding assays demonstrated that MNI-698 and MNI-699 had sub-nanomolar binding affinities against rat striatal 5-HT4 receptors (Ki of 0.20 and 0.07 nM, respectively). PET imaging in rhesus monkey showed that the regional brain distribution of [(18)F]MNI-698 and [(18)F]MNI-699 were consistent with the known densities of 5-HT4 in brain. [(18)F]MNI-698 and [(18)F]MNI-699 are among the first fluorine-18 radiotracers developed for imaging the 5-HT4 receptors in vivo and are currently under preclinical investigation in primates for future human use.

  1. Inappropriate Intra-cervical Injection of Radiotracer for Sentinel Lymph Node Mapping in a Uterine Cervix Cancer Patient: Importance of Lymphoscintigraphy and Blue Dye Injection.

    PubMed

    Kadkhodayan, Sima; Farahabadi, Elham Hosseini; Yousefi, Zohreh; Hasanzadeh, Malihe; Sadeghi, Ramin

    2014-01-01

    Herein, we report a case of sentinel lymph node mapping in a uterine cervix cancer patient, referring to the nuclear medicine department of our institute. Lymphoscintigraphy images showed inappropriate intra-cervical injection of radiotracer. Blue dye technique was applied for sentinel lymph node mapping, using intra-cervical injection of methylene blue. Two blue/cold sentinel lymph nodes, with no pathological involvement, were intra-operatively identified, and the patient was spared pelvic lymph node dissection. The present case underscores the importance of lymphoscintigraphy imaging in sentinel lymph node mapping and demonstrates the added value of blue dye injection in selected patients. It is suggested that pre-operative lymphoscintigraphy imaging be considered as an integral part of sentinel lymph node mapping in surgical oncology. Detailed results of lymphoscintigraphy images should be provided for surgeons prior to surgery, and in case the sentinel lymph nodes are not visualized, use of blue dye for sentinel node mapping should be encouraged.

  2. PET radiotracer [¹⁸F]-P6 selectively targeting COX-1 as a novel biomarker in ovarian cancer: preliminary investigation.

    PubMed

    Perrone, Maria Grazia; Malerba, Paola; Uddin, Md Jashim; Vitale, Paola; Panella, Andrea; Crews, Brenda C; Daniel, Cristina K; Ghebreselasie, Kebreab; Nickels, Mike; Tantawy, Mohammed N; Manning, H Charles; Marnett, Lawrence J; Scilimati, Antonio

    2014-06-10

    Cyclooxygenase-1 (COX-1), but not COX-2, is expressed at high levels in the early stages of human epithelial ovarian cancer where it seems to play a key role in cancer onset and progression. As a consequence, COX-1 is an ideal biomarker for early ovarian cancer detection. A series of novel fluorinated COX-1-targeted imaging agents derived from P6 was developed by using a highly selective COX-1 inhibitor as a lead compound. Among these new compounds, designed by structural modification of P6, 3-(5-chlorofuran-2-yl)-5-(fluoromethyl)-4-phenylisoxazole ([(18/19)F]-P6) is the most promising derivative [IC50 = 2.0 μM (purified oCOX-1) and 1.37 μM (hOVCAR-3 cell COX-1)]. Its tosylate precursor was also prepared and, a method for radio[(18)F]chemistry was developed and optimized. The radiochemistry was carried out using a carrier-free K(18)F/Kryptofix 2.2.2 complex, that afforded [(18)F]-P6 in good radiochemical yield (18%) and high purity (>95%). In vivo PET/CT imaging data showed that the radiotracer [(18)F]-P6 was selectively taken up by COX-1-expressing ovarian carcinoma (OVCAR 3) tumor xenografts as compared with the normal leg muscle. Our results suggest that [(18)F]-P6 might be an useful radiotracer in preclinical and clinical settings for in vivo PET-CT imaging of tissues that express elevated levels of COX-1.

  3. Pre-clinical validation of a novel alpha-7 nicotinic receptor radiotracer, [(3)H]AZ11637326: target localization, biodistribution and ligand occupancy in the rat brain.

    PubMed

    Maier, Donna L; Hill, Geraldine; Ding, Min; Tuke, David; Einstein, Emily; Gurley, David; Gordon, John C; Bock, Mary J; Smith, Jeff S; Bialecki, Russell; Eisman, Mark; Elmore, Charles S; Werkheiser, Jennifer L

    2011-01-01

    The alpha-7 neuronal nicotinic receptor is a novel pharmacological target for psychiatric and cognitive disorders. Selective radiotracer tools for pre-clinical receptor occupancy can facilitate the interpretation of the biological actions of small molecules at a target receptor. We discovered a high affinity nicotinic alpha-7 subtype-selective ligand, AZ11637326, with physical-chemical and pharmacokinetic properties suitable for an in vivo radioligand tool. [(3)H]AZ11637326 synthesis by tritiodehalogenation of the corresponding tribromide precursor yielded a high specific activity radiotracer with high affinity alpha-7 receptor binding in the rat hippocampus determined by autoradiography (Kd = 0.2 nM). When [(3)H]AZ11637326 was administered to rats by intravenous bolus, rapid uptake was measured in the brain followed by a 3-4 fold greater specific binding in regions containing the alpha-7 receptor (frontal cortex, hippocampus, hypothalamus and midbrain) when compared to non-target regions (striatum and cerebellum). Systemic administration of the high affinity alpha-7 receptor antagonist, methyllycaconitine (MLA), or pretreatment with alpha-7 selective agonists (AR-R17779, PyrQTC, DBCO-4-POM, and DBCO-3-POM) significantly blocked the alpha-7 specific binding of [(3)H]AZ11637326 in the rat brain. The rank order of ligand ED(50) values for in vivo alpha-7 receptor occupancy in rat hippocampus was: DBCO-4-POM > DBCO-3-POM ∼ MLA > PyrQTC > AR-R17779. The occupancy affinity shift was consistent with in vitro binding affinity in autoradiography. Our studies established the optimal conditions for [(3)H]AZ11637326 in vivo specific binding in the rat brain and support the use of [(3)H]AZ11637326 as a pre-clinical tool for assessment of novel alpha-7 compounds in drug discovery.

  4. Human Brain Imaging of α7 nAChR with [18F]ASEM: a New PET Radiotracer for Neuropsychiatry and Determination of Drug Occupancy

    PubMed Central

    Wong, Dean F.; Kuwabara, Hiroto; Pomper, Martin; Holt, Daniel P.; Brasic, James R.; George, Noble; Frolov, Boris; Willis, William; Gao, Yongjun; Valentine, Heather; Nandi, Ayon; Gapasin, Lorena; Dannals, Robert F.; Horti, Andrew G.

    2017-01-01

    Purpose Using the α7-nAChR radiotracer, [18F]ASEM, we present the first successful human positron emission tomography (PET) studies. Rodent occupancy with three clinically employed α7-nAChR drugs confirms the specificity of the radiotracer. Procedures Five healthy male subjects were imaged for 90 min following IV [18F]ASEM. Two subjects were scanned for the second time (test/retest; TRV). Mouse biodistribution of [18F]ASEM was carried out in CD1 mice injected with using human equivalent doses of DMXB-A, EVP-6124, and varenicline to block specific binding. Results [18F]ASEM readily entered the brain and peaked at 15 min post-injection with reversible kinetics and a peak %SUV of about 400 %. The regional human brain distribution of [18F]ASEM matched previous in vitro data and baboon PET results. The precuneus, parietal, occipital, cingulate cortexes, putamen, and thalamus showed high values of distribution volume (>20 ml/ml) and binding potentials >1 with TRV averaged 10.8±5.1 %. In mouse distribution studies, there was significant dose-dependent blockade in the mouse brain with DMXB-A as well as the other two α7-nAChR drugs. Conclusions The characteristics of [18F]ASEM are consistent with the ability to quantify α7-nAChR in the human brain. [18F]ASEM is suitable for imaging neuropsychiatric disorders and target engagement (receptor occupancy) of potential α7-nAChR drugs. PMID:25145965

  5. Principles of protein labeling techniques.

    PubMed

    Obermaier, Christian; Griebel, Anja; Westermeier, Reiner

    2015-01-01

    Protein labeling methods prior to separation and analysis have become indispensable approaches for proteomic profiling. Basically, three different types of tags are employed: stable isotopes, mass tags, and fluorophores. While proteins labeled with stable isotopes and mass tags are measured and differentiated by mass spectrometry, fluorescent labels are detected with fluorescence imagers. The major purposes for protein labeling are monitoring of biological processes, reliable quantification of compounds and specific detection of protein modifications and isoforms in multiplexed samples, enhancement of detection sensitivity, and simplification of detection workflows. Proteins can be labeled during cell growth by incorporation of amino acids containing different isotopes, or in biological fluids, cells or tissue samples by attaching specific groups to the ε-amino group of lysine, the N-terminus, or the cysteine residues. The principles and the modifications of the different labeling approaches on the protein level are described; benefits and shortcomings of the methods are discussed.

  6. Optimizing connected component labeling algorithms

    NASA Astrophysics Data System (ADS)

    Wu, Kesheng; Otoo, Ekow; Shoshani, Arie

    2005-04-01

    This paper presents two new strategies that can be used to greatly improve the speed of connected component labeling algorithms. To assign a label to a new object, most connected component labeling algorithms use a scanning step that examines some of its neighbors. The first strategy exploits the dependencies among them to reduce the number of neighbors examined. When considering 8-connected components in a 2D image, this can reduce the number of neighbors examined from four to one in many cases. The second strategy uses an array to store the equivalence information among the labels. This replaces the pointer based rooted trees used to store the same equivalence information. It reduces the memory required and also produces consecutive final labels. Using an array instead of the pointer based rooted trees speeds up the connected component labeling algorithms by a factor of 5 ~ 100 in our tests on random binary images.

  7. Label Ranking Algorithms: A Survey

    NASA Astrophysics Data System (ADS)

    Vembu, Shankar; Gärtner, Thomas

    Label ranking is a complex prediction task where the goal is to map instances to a total order over a finite set of predefined labels. An interesting aspect of this problem is that it subsumes several supervised learning problems, such as multiclass prediction, multilabel classification, and hierarchical classification. Unsurprisingly, there exists a plethora of label ranking algorithms in the literature due, in part, to this versatile nature of the problem. In this paper, we survey these algorithms.

  8. GEO label: The General Framework for Labeling and Certification

    NASA Astrophysics Data System (ADS)

    Bye, B. L.; McCallum, I.; Maso, J.

    2012-04-01

    The Group on Earth Observations (GEO) is coordinating efforts to build a Global Earth Observation System of Systems, or GEOSS. As part of a strategy to increase the involvement of the science and technology community in GEOSS, both as users and developers of GEOSS itself, GEO decided to develop a GEO label concept related to the scientific relevance, quality, acceptance and societal needs for services and data sets of GEOSS. The development of a GEO label is included in the GEO work plan and several projects address the challenges of developing a GEO label concept. Within the different projects developing the GEO label, various perspectives and approaches are being applied. In order to arrive at a generally accepted GEO label concept, a common understanding and basic knowledge of labeling is necessary. Assessment of quality of internationally standardized Earth observation data products implies possible certification. A general understanding of the framework for international standards and certification will also contribute to a more coherent discussion and more efficient development of a GEO label. We will describe the general labeling and certification framework emphasizing the relation to the three elements of the GEO label: quality, user acceptance and relevance. Based on a survey of international labels done by the EGIDA project, we have analyzed the legal framework and organization of labels and certification. We will discuss the frameworks for certification, user ratings, registration and analysis of user requirements. Quality assessment is a particular focus of the analysis and is based on the work done by the GeoViQua project. A GEO label will function both as a data distribution strategy and as a general management system for data. Through a label users can compare different data sets and get access to more information about the relevant data, including quality. A label will provide traceability of data both in the interest of users as well as data

  9. Labeling conventions in isoelectronic sequences

    SciTech Connect

    Maniak, S.T.; Curtis, L.J. )

    1990-08-01

    The isoelectronic exposition of atomic structure properties involves labeling ambiguities when more than one level of the same total angular momentum and parity is present, and an energy ordered labeling of these levels can lead to apparent isoelectronic discontinuities. For example, in the recent oscillator strength calculations for S-like ions by Saloman and Kim (Phys. Rev. A 38, 577 (1988)), abrupt changes in the rates were sometimes observed between one isoelectronic element and the next. We suggest an alternative labeling scheme that removes these discontinuities and produces a smooth isoelectronic variation. This alternative labeling offers advantages for data exposition and for semiempirical interpolation and extrapolation.

  10. Synthesis and in vitro characterization of trans- and cis-[(18)F]-4-methylbenzyl 4-[(pyrimidin-2-ylamino)methyl]-3-fluoropiperidine-1-carboxylates as new potential PET radiotracer candidates for the NR2B subtype N-methyl-D-aspartate receptor.

    PubMed

    Koudih, Radouane; Gilbert, Gwénaëlle; Dhilly, Martine; Abbas, Ahmed; Barré, Louisa; Debruyne, Danièle; Sobrio, Franck

    2012-07-01

    Diastereoisomeric compounds [(18)F]cis- and [(18)F]trans-4-methylbenzyl 4-[(pyrimidin-2-ylamino)methyl]-3-fluoro-piperidine-1-carboxylates were successfully synthesized as new subtype-selective PET radiotracers for imaging the NR2B subunit containing NMDA receptors. Rat brain section autoradiographies demonstrated a high specific binding in NR2B/NMDA receptor rich regions for both radioligands. The measured logD(7.4) values as well as B(max)/K(d) ratios indicated that both radiotracers possess the adequate properties required for PET radiotracers.

  11. Labeled Cocaine Analogs

    DOEpatents

    Goodman, Mark M.; Shi, Bing Zhi; Keil, Robert N.

    1999-03-30

    Novel methods for positron emission tomography or single photon emission spectroscopy using tracer compounds having the structure: ##STR1## where X in .beta. configuration is phenyl, naphthyl; 2,3 or 4-iodophenyl; 2,3 or 4-(trimethylsilyl)phenyl; 3,4,5 or 6-iodonaphthyl; 3,4,5 or 6-(trimethylsilyl)naphthyl; 2,3 or 4-(trialkylstannyl)phenyl; or 3,4,5 or 6-(trialkylstannyl)napthyl Y in .beta. configuration is 2-fluoroethoxy, 3-fluoropropoxy, 4-fluorobutoxy, 2-fluorocyclopropoxy, 2 or 3-fluorocyclobutoxy, R,S 1'-fluoroisopropoxy, R 1'-fluoroisopropoxy, S 1'-fluoroisopropoxy, 1',3'-difluoroisopropoxy, R,S 1'-fluoroisobutoxy, R 1'-fluoroisobutoxy, S 1'-fluoroisobutoxy, R,S 4'-fluoroisobutoxy, R 4'-fluoroisobutoxy, S 4'-fluoroisobutoxy, or 1',1'-di(fluoromethyl)isobutoxy, The compounds bind dopamine transporter protein and can be labeled with .sup.18 F or .sup.123 I for imaging.

  12. 78 FR 66826 - Prior Label Approval System: Generic Label Approval

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-07

    ... poultry products inspection regulations to expand the circumstances in which FSIS will generically approve the labels of meat and poultry products. The Agency also is consolidating the regulations that provide for the approval of labels for meat products and poultry products into a new Code of...

  13. 76 FR 75809 - Prior Label Approval System: Generic Label Approval

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-05

    ... amend the meat and poultry products inspection regulations to expand the circumstances in which FSIS will generically approve the labels of meat and poultry products. The Agency also is proposing to combine the regulations that provide for the approval of labels for meat products and poultry...

  14. Laser labeling, a safe technology to label produce

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laser labeling of fruits and vegetables is an alternative means to label produce. Low energy CO2 laser beams etch the surface showing the contrasting underlying layer. These etched surfaces can promote water loss and potentially allow for entry of decay organisms. The long-term effects of laser labe...

  15. Laser labeling, a safe technology to label produce

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Labeling of the produce has gained marked attention in recent years. Laser labeling technology involves the etching of required information on the surface using a low energy CO2 laser beam. The etching forms alphanumerical characters by pinhole dot matrix depressions. These openings can lead to wat...

  16. Nutrition Marketing on Food Labels

    ERIC Educational Resources Information Center

    Colby, Sarah E.; Johnson, LuAnn; Scheett, Angela; Hoverson, Bonita

    2010-01-01

    Objective: This research sought to determine how often nutrition marketing is used on labels of foods that are high in saturated fat, sodium, and/or sugar. Design and Setting: All items packaged with food labels (N = 56,900) in all 6 grocery stores in Grand Forks, ND were surveyed. Main Outcome Measure(s): Marketing strategy, nutrient label…

  17. 16 CFR 1633.12 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... the Standard shall bear a permanent, conspicuous, and legible label(s) containing the following... with black text. The label text shall comply with the following format requirements: (1) All... as needed for varying information. The label must be white with black text. The label shall...

  18. 21 CFR 201.72 - Potassium labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Potassium labeling. 201.72 Section 201.72 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.72 Potassium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the potassium...

  19. 21 CFR 201.72 - Potassium labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Potassium labeling. 201.72 Section 201.72 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.72 Potassium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the potassium...

  20. 21 CFR 201.72 - Potassium labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Potassium labeling. 201.72 Section 201.72 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.72 Potassium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the potassium...

  1. 21 CFR 201.72 - Potassium labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Potassium labeling. 201.72 Section 201.72 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.72 Potassium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the potassium...

  2. 30 CFR 47.42 - Label contents.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Label contents. 47.42 Section 47.42 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.42 Label contents. When an operator must make a label, the label must— (a)...

  3. 30 CFR 47.42 - Label contents.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Label contents. 47.42 Section 47.42 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.42 Label contents. When an operator must make a label, the label must— (a)...

  4. 30 CFR 47.42 - Label contents.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Label contents. 47.42 Section 47.42 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.42 Label contents. When an operator must make a label, the label must— (a)...

  5. 30 CFR 47.42 - Label contents.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Label contents. 47.42 Section 47.42 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.42 Label contents. When an operator must make a label, the label must— (a)...

  6. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Sodium labeling. 201.64 Section 201.64 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.64 Sodium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the sodium content...

  7. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Sodium labeling. 201.64 Section 201.64 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.64 Sodium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the sodium content...

  8. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Sodium labeling. 201.64 Section 201.64 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.64 Sodium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the sodium content...

  9. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Sodium labeling. 201.64 Section 201.64 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.64 Sodium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the sodium content...

  10. 21 CFR 201.64 - Sodium labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Sodium labeling. 201.64 Section 201.64 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.64 Sodium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the sodium content...

  11. 30 CFR 47.42 - Label contents.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Label contents. 47.42 Section 47.42 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.42 Label contents. When an operator must make a label, the label must— (a)...

  12. 21 CFR 201.71 - Magnesium labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Magnesium labeling. 201.71 Section 201.71 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.71 Magnesium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the magnesium...

  13. 21 CFR 201.71 - Magnesium labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Magnesium labeling. 201.71 Section 201.71 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.71 Magnesium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the magnesium...

  14. 21 CFR 201.71 - Magnesium labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Magnesium labeling. 201.71 Section 201.71 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.71 Magnesium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the magnesium...

  15. 21 CFR 201.71 - Magnesium labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Magnesium labeling. 201.71 Section 201.71 Food and... LABELING Labeling Requirements for Over-the-Counter Drugs § 201.71 Magnesium labeling. (a) The labeling of over-the-counter (OTC) drug products intended for oral ingestion shall contain the magnesium...

  16. Microwave accelerated labeling methods in the synthesis of radioligands for positron emission tomography imaging.

    PubMed

    Kallmerten, Amy E; Alexander, Abigail; Wager, Krista M; Jones, Graham B

    2011-10-01

    Nuclear imaging using positron emission tomography [PET] is a powerful technique with clinical applications which include oncology, cardiovascular disease and CNS disorders. Conventional chemical syntheses of the short half-life radionuclides used in the process however imposes numerous limitations on scope of available ligands. By utilizing microwave assisted synthesis methods many of these limitations can be overcome, paving the way for the design of diverse families of agents with defined cellular targets. This review will survey recent developments in the field with emphasis on the period 2006-2011. Positron emission tomography [PET] has become one of the most powerful in vivo imaging modalities, capable of delivering mm3 resolution of radiotracer distribution and metabolism [1]. When combined with anatomic imaging methods (MRI, CT) co-registered multimode images offer the potential to track metabolic and physiologic events in diseased states and guide and accelerate clinical trials of investigational new drugs. Also, this same methodology can be used to evaluate first pass pharmacokinetics/pharmacodynamics in early stage drug discovery. Though powerful as a technique only a limited number of drugs have seen clinical use and to date only one drug 2-fluoro-deoxy-D-glucose (FDG) has received FDA approval [2]. One of the drawbacks of PET imaging is the need for tracers labeled with an appropriate nuclide and the half-lives of these agents places special constraints on the chemical synthesis. Among the most popular are 11C (t½ =20.4 min) and 18F (t ½ =109.8 min) labeled compounds and this has resulted in a resurgence of interest in practical application of their chemistries [3,4]. This review will focus on microwave mediated methods of acceleration of organic reactions used for the production of labeled PET image contrast agents, with emphasis on the five year period 2006 to 2011.

  17. Labeled Cocaine Analogs

    DOEpatents

    Goodman, Mark M.; Shi, Bing Zhi; Keil, Robert N.

    1999-01-26

    Novel compounds having the structure: ##STR1## where X in .beta. configuration is phenyl, naphthyl; 2,3 or 4-iodophenyl; 2,3 or 4-(trimethylsilyl)phenyl; 3,4,5 or 6-iodonaphthyl; 3,4,5 or 6-(trimethylsilyl)naphthyl; 2,3 or 4-(trialkylstannyl)phenyl; or 3,4,5 or 6-(trialkylstannyl)naphthyl Y in .beta. configuration is Y.sub.1 or Y.sub.2, where Y.sub.1 is 2-fluoroethoxy, 3-fluoropropoxy, 4-fluorobutoxy, 2-fluorocyclopropoxy, 2 or 3-fluorocyclobutoxy, R,S 1'-fluoroisopropoxy, R 1'-fluoroisopropoxy, S 1'-fluoroisopropoxy, 1',3'-difluoroisopropoxy, R,S 1'-fluoroisobutoxy, R 1'-fluoroisobutoxy, S 1'-fluoroisobutoxy, R,S 4'-fluoroisobutoxy, R 4'-fluoroisobutoxy, S 4'-fluoroisobutoxy, or 1',1'-di(fluoromethyl)isobutoxy, and Y.sub.2 is 2-methanesulfonyloxy ethoxy, 3-methanesulfonyloxy propoxy, 4-methanesulfonyloxy butoxy, 2-methanesulfonyloxy cyclopropoxy, 2 or 3-methanesulfonyloxy cyclobutoxy, 1'methanesulfonyloxy isopropoxy, 1'-fluoro, 3'-methanesulfonyloxy isopropoxy, 1'-methanesulfonyloxy, 3'-fluoro isopropoxy, 1'-methanesulfonyloxy isobutoxy, or 4'-methanesulfonyloxy isobutoxy bind dopamine transporter protein and can be labeled with .sup.18 F or .sup.123 I for imaging.

  18. Synthesis Of Labeled Metabolites

    DOEpatents

    Martinez, Rodolfo A.; Silks, III, Louis A.; Unkefer, Clifford J.; Atcher, Robert

    2004-03-23

    The present invention is directed to labeled compounds, for example, isotopically enriched mustard gas metabolites including: [1,1',2,2'-.sup.13 C.sub.4 ]ethane, 1,1'-sulfonylbis[2-(methylthio); [1,1',2,2'-.sup.13 C.sub.4 ]ethane, 1-[[2-(methylsulfinyl)ethyl]sulfonyl]-2-(methylthio); [1,1',2,2'-.sup.13 C.sub.4 ]ethane, 1,1'-sulfonylbis[2-(methylsulfinyl)]; and, 2,2'-sulfinylbis([1,2-.sup.13 C.sub.2 ]ethanol of the general formula ##STR1## where Q.sup.1 is selected from the group consisting of sulfide (--S--), sulfone (--S(O)--), sulfoxide (--S(O.sub.2)--) and oxide (--O--), at least one C* is .sup.13 C, X is selected from the group consisting of hydrogen and deuterium, and Z is selected from the group consisting of hydroxide (--OH), and --Q.sup.2 --R where Q.sup.2 is selected from the group consisting of sulfide (--S--), sulfone(--S(O)--), sulfoxide (--S(O.sub.2)--) and oxide (--O--), and R is selected from the group consisting of hydrogen, a C.sub.1 to C.sub.4 lower alkyl, and amino acid moieties, with the proviso that when Z is a hydroxide and Q.sup.1 is a sulfide, then at least one X is deuterium.

  19. Exploration of the labeling of [11C]Tubastatin A at the hydroxamic acid site with [11C]carbon monoxide

    PubMed Central

    Lu, Shuiyu; Zhang, Yi; Kalin, Jay; Cai, Lisheng; Kozikowski, Alan P.; Pike, Victor W.

    2015-01-01

    We aimed to label tubastatin A (1) with carbon-11 (t1/2 = 20.4 min) in the hydroxamic acid site to provide a potential radiotracer for imaging histone deacetylase 6 (HDAC6) in vivo with positron emission tomography (PET). Initial attempts at a one-pot Pd-mediated insertion of [11C]carbon monoxide between the aryl iodide (2) and hydroxylamine gave low radiochemical yields (< 5%) of [11C]1. Labeling was achieved in useful radiochemical yields (16.1 ± 5.6%, n = 4) through a two-step process based on Pd-mediated insertion of [11C]carbon monoxide between the aryl iodide (2) and p-nitrophenol to give the [11C]p-nitrophenyl ester ([11C]5), followed by ultrasound-assisted hydroxyaminolysis of the activated ester with excess hydroxylamine in DMSO/THF mixture in the presence of a strong phosphazene base P1-t-Bu. However, the success in labeling the hydroxamic acid group of [11C]tubastatin A was not transferable to the labeling of three other model hydroxamic acids. PMID:26647018

  20. Synthesis, radiolabeling and preliminary in vivo evaluation of multimodal radiotracers for PET imaging and targeted radionuclide therapy of pigmented melanoma.

    PubMed

    Billaud, Emilie M F; Maisonial-Besset, Aurélie; Rbah-Vidal, Latifa; Vidal, Aurélien; Besse, Sophie; Béquignat, Jean-Baptiste; Decombat, Caroline; Degoul, Françoise; Audin, Laurent; Deloye, Jean-Bernard; Dollé, Frédéric; Kuhnast, Bertrand; Madelmont, Jean-Claude; Tarrit, Sébastien; Galmier, Marie-Josèphe; Borel, Michèle; Auzeloux, Philippe; Miot-Noirault, Elisabeth; Chezal, Jean-Michel

    2015-03-06

    Melanin pigment represents an attractive target to address specific treatment to melanoma cells, such as cytotoxic radionuclides. However, less than half of the patients have pigmented metastases. Hence, specific marker is required to stratify this patient population before proceeding with melanin-targeted radionuclide therapy. In such a context, we developed fluorinated analogues of a previously studied melanin-targeting ligand, N-(2-diethylaminoethyl)-6-iodoquinoxaline-2-carboxamide (ICF01012). These latter can be labeled either with (18)F or (131)I/(125)I for positron emission tomography imaging (melanin-positive patient selection) and targeted radionuclide therapy purposes. Here we describe the syntheses, radiosyntheses and preclinical evaluations on melanoma-bearing mice model of several iodo- and fluoro(hetero)aromatic derivatives of the ICF01012 scaffold. After preliminary planar gamma scintigraphic and positron emission tomography imaging evaluations, [(125)I]- and [(18)F]-N-[2-(diethylamino)ethyl]-4-fluoro-3-iodobenzamides ([(125)I]4, [(18)F]4) were found to be chemically and biologically stable with quite similar tumor uptakes at 1 h p.i. (9.7 ± 2.6% ID/g and 6.8 ± 1.9% ID/g, respectively).

  1. Algorithms for Labeling Focus Regions.

    PubMed

    Fink, M; Haunert, Jan-Henrik; Schulz, A; Spoerhase, J; Wolff, A

    2012-12-01

    In this paper, we investigate the problem of labeling point sites in focus regions of maps or diagrams. This problem occurs, for example, when the user of a mapping service wants to see the names of restaurants or other POIs in a crowded downtown area but keep the overview over a larger area. Our approach is to place the labels at the boundary of the focus region and connect each site with its label by a linear connection, which is called a leader. In this way, we move labels from the focus region to the less valuable context region surrounding it. In order to make the leader layout well readable, we present algorithms that rule out crossings between leaders and optimize other characteristics such as total leader length and distance between labels. This yields a new variant of the boundary labeling problem, which has been studied in the literature. Other than in traditional boundary labeling, where leaders are usually schematized polylines, we focus on leaders that are either straight-line segments or Bezier curves. Further, we present algorithms that, given the sites, find a position of the focus region that optimizes the above characteristics. We also consider a variant of the problem where we have more sites than space for labels. In this situation, we assume that the sites are prioritized by the user. Alternatively, we take a new facility-location perspective which yields a clustering of the sites. We label one representative of each cluster. If the user wishes, we apply our approach to the sites within a cluster, giving details on demand.

  2. Label Review Training: Module 1: Label Basics, Page 6

    EPA Pesticide Factsheets

    Page 6, Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human health and the environment

  3. Label Review Training: Module 1: Label Basics, Page 5

    EPA Pesticide Factsheets

    Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human health and the environment.

  4. Label Review Training: Module 1: Label Basics, Page 8

    EPA Pesticide Factsheets

    Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human he

  5. Label Review Training: Module 1: Label Basics, Page 9

    EPA Pesticide Factsheets

    Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human health and the environment.

  6. Label Review Training: Module 1: Label Basics, Page 2

    EPA Pesticide Factsheets

    Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human health and the environment.

  7. Label Review Training: Module 1: Label Basics, Page 4

    EPA Pesticide Factsheets

    Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human health and the environment.

  8. Label Review Training: Module 1: Label Basics, Page 3

    EPA Pesticide Factsheets

    Pesticide labels translate results of our extensive evaluations of pesticide products into conditions, directions and precautions that define parameters for use of a pesticide with the goal of ensuring protection of human health and the environment.

  9. A radiotracer study on the volatilization and transport effects of thermochemical reagents used in the analysis of alumina powders by slurry electrothermal vaporization inductively coupled plasma mass spectrometry

    NASA Astrophysics Data System (ADS)

    Peschel, Birgit U.; Herdering, Wilhelm; Broekaert, José A. C.

    2007-02-01

    A neutron-activated Al 2O 3 powder SRM 699 (NIST) containing the γ-radiation emitting radionuclides 51Cr, 59Fe, 60Co and 65Zn has been used to study the influence of thermochemical reagents on the volatilization and transport efficiency for these trace elements in electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) of Al 2O 3 powders. From the signals in the γ-spectra for the radiotracers it has been found that less than 2% of the elements Cr, Fe, Co and Zn is left back in a graphite furnace from Al 2O 3 powders at 2200 °C even without addition of a thermochemical reagent and the latter even was found to decrease the volatilization efficiencies. The recovery for the radiotracers on filters at the end of the transport tube as measured from the signals in the γ-spectra, however, was found to increase in most cases (i.e. from about 10% to more than 20%) when Pd(NO 3) 2, Pd(NO 3) 2 + Mg(NO 3) 2, PdCl 2, IrCl 3, SnCl 2, AgCl, NaF, NH 4Cl and NH 4F were added at amounts generally used in electrothermal vaporization inductively coupled plasma mass spectrometry. However, when adding higher amounts as stoichiometrically required for a complete halogenation of the sample matrix in the case of AgCl, C 8F 15O 2Na, IrCl 3 or PdCl 2 the transport efficiencies considerably decrease again. As shown in the case of NH 4Cl the amount of thermochemical reagent used has to be optimized so as to obtain maximum analyte transport efficiencies. A comparison of the influence of NH 4Cl on the transport efficiencies with its influence on the ETV-ICP-MS signals for Fe demonstrates the importance of transport efficiency changes for the effects of thermochemical reagents in electrothermal vaporization inductively coupled plasma mass spectrometry.

  10. 49 CFR 172.442 - CORROSIVE label.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.442 CORROSIVE label. (a) Except for size and color, the CORROSIVE label...

  11. 49 CFR 172.442 - CORROSIVE label.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.442 CORROSIVE label. (a) Except for size and color, the CORROSIVE label...

  12. 49 CFR 172.442 - CORROSIVE label.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.442 CORROSIVE label. (a) Except for size and color, the CORROSIVE label...

  13. 40 CFR 94.212 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... shall be of a color that contrasts with the background of the label: (1) The label heading: Marine...) to be designated as Blue Sky Series engines must contain the statement on the label: “Blue Sky...

  14. 40 CFR 94.212 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... shall be of a color that contrasts with the background of the label: (1) The label heading: Marine...) to be designated as Blue Sky Series engines must contain the statement on the label: “Blue Sky...

  15. 40 CFR 94.212 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... shall be of a color that contrasts with the background of the label: (1) The label heading: Marine...) to be designated as Blue Sky Series engines must contain the statement on the label: “Blue Sky...

  16. 40 CFR 94.212 - Labeling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... shall be of a color that contrasts with the background of the label: (1) The label heading: Marine...) to be designated as Blue Sky Series engines must contain the statement on the label: “Blue Sky...

  17. 16 CFR 305.17 - Television labeling.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... STAR logo on the label as illustrated in Sample Labels in appendix L. The logo must be 0.375″ wide... Environmental Protection Agency covering the televisions to be labeled may add the ENERGY STAR logo to...

  18. 21 CFR 331.80 - Professional labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... HUMAN USE ANTACID PRODUCTS FOR OVER-THE-COUNTER (OTC) HUMAN USE Labeling § 331.80 Professional labeling..., muscle weakness, and osteomalacia. (b) Professional labeling for an antacid-antiflatulent combination...

  19. 21 CFR 331.80 - Professional labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... HUMAN USE ANTACID PRODUCTS FOR OVER-THE-COUNTER (OTC) HUMAN USE Labeling § 331.80 Professional labeling..., muscle weakness, and osteomalacia. (b) Professional labeling for an antacid-antiflatulent combination...

  20. 21 CFR 331.80 - Professional labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... HUMAN USE ANTACID PRODUCTS FOR OVER-THE-COUNTER (OTC) HUMAN USE Labeling § 331.80 Professional labeling..., muscle weakness, and osteomalacia. (b) Professional labeling for an antacid-antiflatulent combination...

  1. Soil Fumigant Labels - Dimethyl Disulfide (DMDS)

    EPA Pesticide Factsheets

    Search by EPA registration number, product name, or company and follow the link to the Pesticide Product Labeling System (PPLS) for label details. Updated labels include new safety requirements for buffer zones and related measures.

  2. Mobile Application for Pesticide Label Matching

    EPA Pesticide Factsheets

    The label matching application will give inspectors the ability to instantly compare pesticide product labels against state and federal label databases via their cell phone, tablet or other mobile device.

  3. A comparative evaluation of the dopamine D(2/3) agonist radiotracer [11C](-)-N-propyl-norapomorphine and antagonist [11C]raclopride to measure amphetamine-induced dopamine release in the human striatum.

    PubMed

    Narendran, Rajesh; Mason, N Scott; Laymon, Charles M; Lopresti, Brian J; Velasquez, Natalie D; May, Maureen A; Kendro, Steve; Martinez, Diana; Mathis, Chester A; Frankle, W Gordon

    2010-05-01

    (-)-N-Propyl-norapomorphine (NPA) is a full dopamine D(2/3) receptor agonist, and [(11)C]NPA is a suitable radiotracer to image D(2/3) receptors configured in a state of high affinity for agonists with positron emission tomography (PET). In this study, the vulnerability of the in vivo binding of [11C]NPA to acute fluctuation in synaptic dopamine was assessed with PET in healthy humans and compared with that of the reference D(2/3) receptor antagonist radiotracer [11C]raclopride. Ten subjects (eight females and two males) were studied on two separate days, a minimum of 1 week apart, both with [11C]raclopride and [11C]NPA at baseline and after the administration of 0.5 mg x kg(-1) oral d-amphetamine. Kinetic modeling with an arterial input function was used to derive the binding potential relative to nonspecific uptake (BPND) in the ventral striatum (VST), caudate (CAD), and putamen (PUT). [11C]Raclopride BPND was significantly reduced by 9.7 +/- 4.4, 8.4 +/- 4.2, and 14.7 +/- 4.8% after amphetamine administration in the VST, CAD, and PUT. [11C]NPA BPND was also reduced significantly, by 16.0 +/- 7.0, 16.1 +/- 6.1, and 21.9 +/- 4.9% after the same dose of amphetamine in the VST, CAD, and PUT. Although these results suggest that [11C]NPA is more vulnerable to endogenous competition by dopamine compared with [11C]raclopride by a factor of 1.49 to 1.90, the same data for a related outcome measure, binding potential relative to plasma concentration, was not significant. Nevertheless, these data add to the growing literature that suggests D(2/3) agonist radiotracers are more vulnerable to endogenous competition by dopamine than existing D(2/3) antagonist radiotracers.

  4. In vivo biodistribution of two ( sup 18 F)-labelled muscarinic cholinergic receptor ligands: 2-( sup 18 F)- and 4-( sup 18 F)-fluorodexetimide

    SciTech Connect

    Wilson, A.A.; Scheffel, U.A.; Dannals, R.F.; Stathis, M.; Ravert, H.T.; Wagner, H.N. Jr. )

    1991-01-01

    Two ({sup 18}F)-labelled analogues of the potent muscarinic cholinergic receptor (m-AChR) antagonist, dexetimide, were evaluated as potential ligands for imaging m-AChR by positron emission tomography (PET). Intravenous administration of both 2-({sup 18}F)- or 4-({sup 18}F)-fluorodexetimide resulted in high brain uptake of radioactivity in mice. High binding levels were observed in m-AChR rich areas, such as cortex and striatum, with low levels in the receptor-poor cerebellum. Uptake of radioactivity was saturable and could be blocked by pre-administration of dexetimide or atropine. Drugs with different sites of action were ineffective at blocking receptor binding. The results indicate that both radiotracers are promising candidates for use in PET studies.

  5. Approximation Algorithms for Free-Label Maximization

    NASA Astrophysics Data System (ADS)

    de Berg, Mark; Gerrits, Dirk H. P.

    Inspired by air traffic control and other applications where moving objects have to be labeled, we consider the following (static) point labeling problem: given a set P of n points in the plane and labels that are unit squares, place a label with each point in P in such a way that the number of free labels (labels not intersecting any other label) is maximized. We develop efficient constant-factor approximation algorithms for this problem, as well as PTASs, for various label-placement models.

  6. New Labeling for Neonicotinoid Pesticides

    EPA Pesticide Factsheets

    These documents, a graphic of the bee advisory box and letters to pesticide registrants, describe steps by EPA to change pesticide labels to better protect pollinators by being clearer and more precise in their directions for pesticide application.

  7. Relaxation labeling using modular operators

    SciTech Connect

    Duncan, J.S.; Frei, W.

    1983-01-01

    Probabilistic relaxation labeling has been shown to be useful in image processing, pattern recognition, and artificial intelligence. The approaches taken to date have been encumbered with computationally extensive summations which generally prevent real-time operation and/or easy hardware implementation. The authors present a new and unique approach to the relaxation labeling problem using modular, VLSI-oriented hierarchical complex operators. One of the fundamental concepts of this work is the representation of the probability distribution of the possible labels for a given object (pixel) as an ellipse, which may be summed with neighboring object's distribution ellipses, resulting in a new, relaxed label space. The mathematical development of the elliptical approach will be presented and compared to more classical approaches, and a hardware block diagram that shows the implementation of the relaxation scheme using vlsi chips will be presented. Finally, results will be shown which illustrate applications of the modular scheme, iteratively, to both edges and lines. 13 references.

  8. "Off-Label" Drug Use

    MedlinePlus

    ... the Connecticut Attorney General for possible promotion and marketing of the off-label uses of the drug. ... cited improved energy and quality of life. The marketing of these three drugs and the doses used ...

  9. Meat and Poultry Labeling Terms

    MedlinePlus

    ... Food Safety and Inspection Service and the Agriculture Marketing Service have officially evaluated a meat product for ... refer to these factsheets from the USDA Agricultural Marketing Service: Organic Food Standards and Labels: The Facts ...

  10. How to Read Drug Labels

    MedlinePlus

    ... Home > Healthy Aging > Drugs and alternative medicine Healthy Aging How to read drug labels Printer-friendly version ... html Connect with other organizations National Institute on Aging, NIH, HHS http://www.nia.nih.gov/ U.S. ...

  11. Locating the Vehicle Emissions Label

    EPA Pesticide Factsheets

    The EPA vehicle emissions label is entitled Vehicle Emission Control Information and contains the name and trademark of the manufacturer and an unconditional statement of compliance with EPA emission regulations.

  12. Microfluidic technology platforms for synthesizing, labeling and measuring the kinetics of transport and biochemical reactions for developing molecular imaging probes

    SciTech Connect

    Phelps, Michael E.

    2009-09-01

    Radiotracer techniques are used in environmental sciences, geology, biology and medicine. Radiotracers with Positron Emission Tomography (PET) provided biological examinations of ~3 million patients 2008. Despite the success of positron labeled tracers in many sciences, there is limited access in an affordable and convenient manner to develop and use new tracers. Integrated microfluidic chips are a new technology well matched to the concentrations of tracers. Our goal is to develop microfluidic chips and new synthesis approaches to enable wide dissemination of diverse types of tracers at low cost, and to produce new generations of radiochemists for which there are many unfilled jobs. The program objectives are to: 1. Develop an integrated microfluidic platform technology for synthesizing and 18F-labeling diverse arrays of different classes of molecules. 2. Incorporate microfluidic chips into small PC controlled devices (“Synthesizer”) with a platform interfaced to PC for electronic and fluid input/out control. 3. Establish a de-centralized model with Synthesizers for discovering and producing molecular imaging probes, only requiring delivery of inexpensive [18F]fluoride ion from commercial PET radiopharmacies vs the centralized approach of cyclotron facilities synthesizing and shipping a few different types of 18F-probes. 4. Develop a position sensitive avalanche photo diode (PSAPD) camera for beta particles embedded in a microfluidic chip for imaging and measuring transport and biochemical reaction rates to valid new 18F-labeled probes in an array of cell cultures. These objectives are met within a research and educational program integrating radio-chemistry, synthetic chemistry, biochemistry, engineering and biology in the Crump Institute for Molecular Imaging. The Radiochemistry Training Program exposes PhD and post doctoral students to molecular imaging in vitro in cells and microorganisms in microfluidic chips and in vivo with PET, from new technologies

  13. Electrothermal branding for embryo labeling.

    PubMed

    Wang, L; Beebe, D J; Williams, A R; Easley, K D

    1997-11-01

    A novel embryo labeling technique based on electrothermal branding is developed. Two types of micro branding irons are fabricated and tested. One utilizes 25 microns tungsten wire as the heating element. The other utilizes surface micromachining techniques to fabricate polysilicon branding irons. The thermal behavior of the branding irons and the heat distributions in the embryos are analytically modeled. Micron-scale labels on unfertilized bovine embryos are achieved.

  14. Measurement of Bmax and Kd with the glycine transporter 1 radiotracer 18F-MK6577 using a novel multi-infusion paradigm

    PubMed Central

    Xia, Yan; Zheng, Ming-Qiang; Holden, Daniel; Lin, Shu-fei; Kapinos, Michael; Ropchan, Jim; Gallezot, Jean-Dominique; Huang, Yiyun; Carson, Richard E

    2015-01-01

    Glycine is a co-agonist of glutamate at the NMDA receptor. Glycine transporter 1 (GlyT1) inhibitors are reported to be potential therapeutic agents for schizophrenia. 18F-MK6577 is a new positron emission tomography (PET) radiotracer useful for imaging brain GlyT1 and its occupancy in humans. We devised a novel multi-infusion paradigm of radiolabeled and unlabeled compound and an iterative linear/nonlinear alternating fitting method to allow for the determination of in vivo affinity (Kd) and target concentration (Bmax) images, constraining Kd to be uniform across the brain. This paradigm was tested with 18F-MK6577 in baboons. Voxel-based analysis produced high quality Bmax images and reliable Kd estimates, and also suggested that the nondisplaceable distribution volume (VND) is not uniform throughout the brain. In vivo GlyT1 Kd was estimated to be 1.87 nmol/L for 18F-MK6577, and the rank order of GlyT1 distribution measured in the baboon brain was: high in the brainstem (133 nmol/L), medium in the cerebellum (83 nmol/L), and low in the cortex (30 nmol/L). These in vivo Kd and Bmax values agreed well with those determined in vitro, thus validating our novel multi-infusion approach. PMID:26198176

  15. Methodological considerations regarding the use of inorganic 197Hg(II) radiotracer to assess mercury methylation potential rates in lake sediment

    USGS Publications Warehouse

    Perez, Catan S.; Guevara, S.R.; Marvin-DiPasquale, M.; Magnavacca, C.; Cohen, I.M.; Arribere, M.

    2007-01-01

    Methodological considerations on the determination of benthic methyl-mercury (CH3Hg) production potentials were investigated on lake sediment, using 197Hg radiotracer. Three methods to arrest bacterial activity were compared: flash freezing, thermal sterilization, and ??-irradiation. Flash freezing showed similar CH3Hg recoveries as thermal sterilization, which was both 50% higher than the recoveries obtained with ??-ray irradiation. No additional radiolabel was recovered in kill-control samples after an additional 24 or 65 h of incubation, suggesting that all treatments were effective at arresting Hg(II)-methylating bacterial activity, and that the initial recoveries are likely due to non-methylated 197Hg(II) carry-over in the organic extraction and/or [197Hg]CH3Hg produced via abiotic reactions. Two CH3Hg extraction methods from sediment were compared: (a) direct extraction into toluene after sediment leaching with CuSO4 and HCl and (b) the same extraction with an additional back-extraction step to thiosulphate. Similar information was obtained with both methods, but the low efficiency observed and the extra work associated with the back-extraction procedure represent significant disadvantages, even tough the direct extraction involves higher Hg(II) carry over. ?? 2007 Elsevier Ltd. All rights reserved.

  16. Metabolism, distribution, and excretion of deoxynivalenol with combined techniques of radiotracing, high-performance liquid chromatography ion trap time-of-flight mass spectrometry, and online radiometric detection.

    PubMed

    Wan, Dan; Huang, Lingli; Pan, Yuanhu; Wu, Qinghua; Chen, Dongmei; Tao, Yanfei; Wang, Xu; Liu, Zhenli; Li, Juan; Wang, Liye; Yuan, Zonghui

    2014-01-08

    Dispositions of deoxynivalenol (DON) in rats and chickens were investigated, using a radiotracer method coupled with a novel γ-accurate radioisotope counting (γ-ARC) radio-high-performance liquid chromatography ion trap time-of-flight tandem mass spectrometry (radio-HPLC-IT-TOF-MS/MS) system. 3β-(3)H-DON was chemically synthesized and orally administrated to both sexes of rats and chickens as single or multiple doses. The results showed that DON was widely distributed and quickly eliminated in all tissues. The highest concentration was found in the gastrointestinal tract at 6 h post-administration. Substantially lower levels were detected in the kidney, liver, heart, lung, spleen, and brain. Three new metabolites were identified tentatively as 10-deoxynivalenol-sulfonate, 10-deepoxy-deoxynivalenol (DOM-1)-sulfonate, and deoxynivalenol-3α-sulfate. Deoxynivalenol-3α-sulfate was a major metabolite in chickens, while the major forms in rats were DOM-1 and DON. Additionally, a higher excretion rate in urine was observed in female rats than in male rats. The differences in metabolite profiles and excretion rates, which suggested diverse ways to detoxify, may relate to the different tolerances in different genders or species.

  17. Synthesis and Preliminary PET Imaging Studies of a FAAH Radiotracer ([¹¹C]MPPO) Based on α-Ketoheterocyclic Scaffold.

    PubMed

    Wang, Lu; Yui, Joji; Wang, Qifan; Zhang, Yiding; Mori, Wakana; Shimoda, Yoko; Fujinaga, Masayuki; Kumata, Katsushi; Yamasaki, Tomoteru; Hatori, Akiko; Rotstein, Benjamin H; Collier, Thomas Lee; Ran, Chongzhao; Vasdev, Neil; Zhang, Ming-Rong; Liang, Steven H

    2016-01-20

    Fatty acid amide hydrolase (FAAH) is one of the principle enzymes for metabolizing endogenous cannabinoid neurotransmitters such as anandamide, and thus regulates endocannabinoid (eCB) signaling. Selective pharmacological blockade of FAAH has emerged as a potential therapy to discern the endogenous functions of anandamide-mediated eCB pathways in anxiety, pain, and addiction. Quantification of FAAH in the living brain by positron emission tomography (PET) would help our understanding of the endocannabinoid system in these conditions. While most FAAH radiotracers operate by an irreversible ("suicide") binding mechanism, a FAAH tracer with reversibility would facilitate quantitative analysis. We have identified and radiolabeled a reversible FAAH inhibitor, 7-(2-[(11)C]methoxyphenyl)-1-(5-(pyridin-2-yl)oxazol-2-yl)heptan-1-one ([(11)C]MPPO) in 13% radiochemical yield (nondecay corrected) with >99% radiochemical purity and 2 Ci/μmol (74 GBq/μmol) specific activity. The tracer showed moderate brain uptake (0.8 SUV) with heterogeneous brain distribution. However, blocking studies with a potent FAAH inhibitor URB597 demonstrated a low to modest specificity to the target. Measurement of lipophilicity, metabolite, and efflux pathway analysis were also performed to study the pharmacokinetic profile of [(11)C]MPPO. In all, we reported an efficient radiolabeling and preliminary evaluation of the first-in-class FAAH inhibitor [(11)C]MPPO with α-ketoheterocyclic scaffold.

  18. Depuration and uptake kinetics of I, Cs, Mn, Zn and Cd by the earthworm (Lumbricus terrestris) in radiotracer-spiked litter

    SciTech Connect

    Sheppard, S.C.; Evenden, W.G.; Cornwell, T.C.

    1997-10-01

    The relative depuration and uptake kinetics of contaminants should be known to interpret appropriately the use of organisms such as earthworms in environmental bioassays and monitoring. For example, 14-d earthworm bioassays should be interpreted with the knowledge that some contaminants will continue to accumulate in tissues for months. The radiotracers {sup 125}I, {sup 134}Cs, {sup 54}Mn, {sup 65}Zn, and {sup 109}Cd were applied to deciduous litter and specimens of Lumbricus terrestris were exposed, either to litter alone or to litter on the top of soil columns. Depuration was monitored for 120 d and uptake, in a separate experiment, for 20 d. Both depuration and uptake were described using two-phase, first-order statistical models. Cut clearance had a mean half-time of 1.4 d. The mean half-time for physiological depuration decreased from I (210 d) > Cd (150 d) > Zn (69 d) > Mn (40 d) > Cs (24 d). Both the depuration and the uptake experiments were necessary to resolve even partially the multiphase processes. Earthworm/soil dry weight concentration ratios decreased from Cd > Zn > I {ge} Cs {ge} Mn. The very slow kinetics indicate that tissue concentrations will increase continuously for a long time, with important implications for subsequent food-chain transfers.

  19. F-18 Labeled RGD Probes Based on Bioorthogonal Strain-Promoted Click Reaction for PET Imaging.

    PubMed

    Kim, Hye Lan; Sachin, Kalme; Jeong, Hyeon Jin; Choi, Wonsil; Lee, Hyun Soo; Kim, Dong Wook

    2015-04-09

    A series of fluorine-substituted monomeric and dimeric cRGD peptide derivatives, such as cRGD-ADIBOT-F (ADIBOT = azadibenzocyclooctatriazole), di-cRGD-ADIBOT-F, cRGD-PEG5-ADIBOT-F, and di-cRGD-PEG5-ADIBOT-F, were prepared by strain-promoted alkyne azide cycloaddition (SPAAC) reaction of the corresponding aza-dibenzocyclooctyne (ADIBO) substituted peptides with a fluorinated azide 3. Among these cRGD derivatives, di-cRGD-PEG5-ADIBOT-F had the highest binding affinity in a competitive binding assay compared to other derivatives and even the original cRGDyk. On the basis of the in vitro study results, di-cRGD-PEG5-ADIBOT-(18)F was prepared from a SPAAC reaction with (18)F-labeled azide and subsequent chemo-orthogonal scavenger-assisted separation without high performance liquid chromatography (HPLC) purification in 92% decay-corrected radiochemical yield (dcRCY) with high specific activity for further in vivo positron emission tomography (PET) imaging study. In vivo PET imaging study and biodistribution data showed that this radiotracer allowed successful visualization of tumors with good tumor-to-background contrast and significantly higher tumor uptake compared to other major organs.

  20. Synthesis and biological evaluation of (68) Ga-labeled Pteroyl-Lys conjugates for folate receptor-targeted tumor imaging.

    PubMed

    Zhang, Xuran; Yu, Qian; He, Yingfang; Zhang, Chun; Zhu, Hua; Yang, Zhi; Lu, Jie

    2016-07-01

    In order to develop novel (68) Ga-labeled PET tracers for folate receptor imaging, two DOTA-conjugated Pteroyl-Lys derivatives, Pteroyl-Lys-DOTA and Pteroyl-Lys-DAV-DOTA, were designed, synthesized and radiolabeled with (68) Ga. Biological evaluations of the two radiotracers were performed with FR-positive KB cell line and athymic nude mice bearing KB tumors. Both (68) Ga-DOTA-Lys-Pteroyl and (68) Ga-DOTA-DAV-Lys-Pteroyl exhibited receptor specific binding in KB cells in vitro. The tumor uptake values of (68) Ga-DOTA-Lys-Pteroyl and (68) Ga-DOTA-DAV-Lys-Pteroy were 10.06 ± 0.59%ID/g and 11.05 ± 0.60%ID/g at 2 h post-injection, respectively. Flank KB tumor was clearly visualized with (68) Ga-DOTA-DAV-Lys-Pteroyl by Micro-PET imaging at 2 h post-injection, suggesting the feasibility of using (68) Ga-labeled Pteroyl-Lys conjugates as a novel class of FR targeted probes.

  1. Biodistribution and kinetic studies of technetium-99m labeled Naja naja karachiensis venom via gamma scintigraphic and SPECT images.

    PubMed

    Bin-Asad, Muhammad Hassham-Hassan; e-Sabih, Durr; Ahmad, Israr; Choudhry, Bashir Ahmad; Murtaza, Ghulam; Hussain, Izhar

    2015-07-01

    Naja naja karachiensis have been responsible for plentiful deaths in Pakistan. To investigate bio distribution and blood kinetics, venom was labeled with the radiotracer (technetium-99m) by following the method of direct labeling technique. Its maximum labeling percentage was 97.7% (pH 6, 100 µg stannous chloride dihydrate) which was higher than some other reported venom. Radio labeled venom was stable for more than 4 hours both in vivo (96%) and in vitro (serum 94.1%, saline 94.3%) experimentations. Intravenous doses of venom (250 µg, 0.5 mCi) were found to be evenly distributed (having R/L ratio=1.0) in all parts of sacrificed rabbits. Kidneys (53.75% activity/g) and urinary bladder (23.70% activity/g) were found with the copious quantity of injected dose of venom. Rest of all other organs was found with subsequent remaining dose of venom. Among them, lungs (14.2% activity/g), liver (4.32% activity/g), bones (1.38% activity/g), heart (0.8% activity/g), blood (0.56% activity/g), skin (0.45% activity/g), intestines (0.35% activity/g), skeleton muscles (0.3% activity/g), brain (0.14% activity/g) and stomach (0.05% activity/g) are included. After 24 hours of injection, poisoned blood of rabbits was almost cleared from venom. Gamma scintigraphic images (up to 2 hours) along with bio distribution suggest that kidneys are main organs of excretion in rabbits. Elimination started immediately after administration of venom however, possible sites for metabolism of venom are liver and lungs. More accumulation of venom in heart compared to brain suggests its higher affinity (thus possible higher toxicity) to cardiac muscles as compared to brain tissues.

  2. 21 CFR 225.180 - Labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 4 2014-04-01 2014-04-01 false Labeling. 225.180 Section 225.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR MEDICATED FEEDS Labeling § 225.180 Labeling. Labels shall...

  3. 21 CFR 225.180 - Labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false Labeling. 225.180 Section 225.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR MEDICATED FEEDS Labeling § 225.180 Labeling. Labels shall...

  4. 21 CFR 225.180 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 4 2013-04-01 2013-04-01 false Labeling. 225.180 Section 225.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR MEDICATED FEEDS Labeling § 225.180 Labeling. Labels shall...

  5. 21 CFR 225.180 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 4 2012-04-01 2012-04-01 false Labeling. 225.180 Section 225.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR MEDICATED FEEDS Labeling § 225.180 Labeling. Labels shall...

  6. 21 CFR 225.180 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Labeling. 225.180 Section 225.180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR MEDICATED FEEDS Labeling § 225.180 Labeling. Labels shall...

  7. 21 CFR 895.25 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... eliminated by labeling or a change in labeling, or change in advertising if the device is a restricted device... person(s) responsible for the labeling or advertising of the device specifying: (1) The deception or risk... labeling, or change in advertising if the device is a restricted device, necessary to correct the...

  8. 40 CFR 211.108 - Sample label.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Sample label. 211.108 Section 211.108 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS PRODUCT NOISE LABELING General Provisions § 211.108 Sample label. Examples of labels conforming to the requirements...

  9. 40 CFR 156.10 - Labeling requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 156.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS LABELING REQUIREMENTS FOR PESTICIDES AND DEVICES General Provisions § 156.10 Labeling requirements. (a) General—(1) Contents of the label. Every pesticide product shall bear a label containing the...

  10. 40 CFR 156.10 - Labeling requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 156.10 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) PESTICIDE PROGRAMS LABELING REQUIREMENTS FOR PESTICIDES AND DEVICES General Provisions § 156.10 Labeling requirements. (a) General—(1) Contents of the label. Every pesticide product shall bear a label containing the...

  11. 21 CFR 606.121 - Container label.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... color scheme may be used for differentiating ABO Blood groups: Blood group Color of label O Blue A... CURRENT GOOD MANUFACTURING PRACTICE FOR BLOOD AND BLOOD COMPONENTS Additional Labeling Standards for Blood and Blood Components § 606.121 Container label. (a) The container label requirements are designed...

  12. 40 CFR 211.104 - Label content.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Label content. 211.104 Section 211.104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS PRODUCT NOISE LABELING General Provisions § 211.104 Label content. The following data and information must be on the label of all products for...

  13. 40 CFR 211.104 - Label content.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Label content. 211.104 Section 211.104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS PRODUCT NOISE LABELING General Provisions § 211.104 Label content. The following data and information must be on the label of all products for...

  14. 40 CFR 211.104 - Label content.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Label content. 211.104 Section 211.104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS PRODUCT NOISE LABELING General Provisions § 211.104 Label content. The following data and information must be on the label of all products for...

  15. 40 CFR 211.104 - Label content.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Label content. 211.104 Section 211.104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS PRODUCT NOISE LABELING General Provisions § 211.104 Label content. The following data and information must be on the label of all products for...

  16. 40 CFR 211.104 - Label content.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Label content. 211.104 Section 211.104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS PRODUCT NOISE LABELING General Provisions § 211.104 Label content. The following data and information must be on the label of all products for...

  17. How to Read a Nutrition Facts Label

    MedlinePlus Videos and Cool Tools

    ... to 2-Year-Old How to Read a Nutrition Facts Label (Video) KidsHealth > For Parents > How to Read a Nutrition Facts Label (Video) Print A A A en ... nutricionales (video) Most packaged foods come with a Nutrition Facts label. These labels have a lot of ...

  18. 21 CFR 610.60 - Container label.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 7 2011-04-01 2010-04-01 true Container label. 610.60 Section 610.60 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) BIOLOGICS GENERAL BIOLOGICAL PRODUCTS STANDARDS Labeling Standards § 610.60 Container label. (a) Full label....

  19. 99mTc(CO)3-labeled pamidronate and alendronate for bone imaging.

    PubMed

    Palma, Elisa; Correia, João D G; Oliveira, Bruno L; Gano, Lurdes; Santos, Isabel C; Santos, Isabel

    2011-03-28

    Bone scintigraphy with (99m)Technetium-methylenediphosphonate ((99m)Tc-MDP) or (99m)Technetium-hydroxymethylenediphosphonate ((99m)Tc-HMDP) presents several limitations, namely low specificity, uncertainty in the radiopharmaceutical's molecular structure and long acquisition time after injection. Aiming to find bone-seeking radiotracers based on the core fac-[(99m)Tc(CO)(3)](+) with improved chemical and biological properties, we synthesized new conjugates (pz-PAM and pz-ALN), comprising a pyrazolyl-diamine chelating unit (pz: N,N,N donor atom set) for metal stabilization and a pendant pamidronate (PAM) or alendronate (ALN) moiety for bone targeting. The reaction of the conjugates with fac-[(99m)Tc(CO)(3)](+) yielded (> 95%) the stable complexes fac-[(99m)Tc(CO)(3)(pz-PAM)](-) (2a) and fac-[(99m)Tc(CO)(3)(pz-ALN)](-) (3a), which have been characterized by comparing their HPLC gamma-traces with the UV-vis traces of the Re surrogates 2 and 3, respectively. 2a and 3a bind strongly onto hydroxyapatite. The biodistribution studies in Balb-c mice have shown that 2a and 3a presented an high bone uptake (2a 18.3 ± 0.6% I.D./g, 3a 17.3 ± 6.1% I.D./g, at 1 h post injection), similar to (99m)Tc-MDP (17.1 ± 2.4% I.D./g, at 1 h post injection), with comparable clearance from most tissues and increased total excretion (2a 66% I.D., 3a 67% I.D. and (99m)Tc-MDP 49% I.D., at 1 h post injection). The bone-to-blood (2a 86.2, 3a 74.7) and the bone-to-muscle ratios (2a 77.7, 3a 79.0) are higher than the ones found for (99m)Tc-MDP (70.9, 47.9), at 4 h post injection. Planar whole-body gamma camera images of the rats injected with the (99m)Tc(CO)(3)-labeled pamidronate (2a) and alendronate (3a) confirmed the overall adequate biological profile of the new radiotracers for bone imaging.

  20. 49 CFR 172.430 - POISON label.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false POISON label. 172.430 Section 172.430... SECURITY PLANS Labeling § 172.430 POISON label. (a) Except for size and color, the POISON label must be as follows: EC02MR91.029 (b) In addition to complying with § 172.407, the background on the POISON label...

  1. 49 CFR 172.430 - POISON label.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false POISON label. 172.430 Section 172.430... SECURITY PLANS Labeling § 172.430 POISON label. (a) Except for size and color, the POISON label must be as follows: EC02MR91.029 (b) In addition to complying with § 172.407, the background on the POISON label...

  2. 49 CFR 172.430 - POISON label.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false POISON label. 172.430 Section 172.430... SECURITY PLANS Labeling § 172.430 POISON label. (a) Except for size and color, the POISON label must be as follows: EC02MR91.029 (b) In addition to complying with § 172.407, the background on the POISON label...

  3. 49 CFR 172.430 - POISON label.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false POISON label. 172.430 Section 172.430... SECURITY PLANS Labeling § 172.430 POISON label. (a) Except for size and color, the POISON label must be as follows: EC02MR91.029 (b) In addition to complying with § 172.407, the background on the POISON label...

  4. 49 CFR 172.430 - POISON label.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false POISON label. 172.430 Section 172.430... SECURITY PLANS Labeling § 172.430 POISON label. (a) Except for size and color, the POISON label must be as follows: EC02MR91.029 (b) In addition to complying with § 172.407, the background on the POISON label...

  5. Metrics for Labeled Markov Systems

    NASA Technical Reports Server (NTRS)

    Desharnais, Josee; Jagadeesan, Radha; Gupta, Vineet; Panangaden, Prakash

    1999-01-01

    Partial Labeled Markov Chains are simultaneously generalizations of process algebra and of traditional Markov chains. They provide a foundation for interacting discrete probabilistic systems, the interaction being synchronization on labels as in process algebra. Existing notions of process equivalence are too sensitive to the exact probabilities of various transitions. This paper addresses contextual reasoning principles for reasoning about more robust notions of "approximate" equivalence between concurrent interacting probabilistic systems. The present results indicate that:We develop a family of metrics between partial labeled Markov chains to formalize the notion of distance between processes. We show that processes at distance zero are bisimilar. We describe a decision procedure to compute the distance between two processes. We show that reasoning about approximate equivalence can be done compositionally by showing that process combinators do not increase distance. We introduce an asymptotic metric to capture asymptotic properties of Markov chains; and show that parallel composition does not increase asymptotic distance.

  6. Positron emitter labeled enzyme inhibitors

    DOEpatents

    Fowler, Joanna S.; MacGregor, Robert R.; Wolf, Alfred P.; Langstrom, Bengt

    1990-01-01

    This invention involves a new strategy for imaging and mapping enzyme activity in the living human and animal body using positron emitter-labeled suicide enzyme inactivators or inhibitors which become covalently bound to the enzyme as a result of enzymatic catalysis. Two such suicide inactivators for monoamine oxidase have been labeled with carbon-11 and used to map the enzyme subtypes in the living human and animal body using PET. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography.

  7. Positron emitter labeled enzyme inhibitors

    SciTech Connect

    Fowler, J.S.; MacGregor, R.R.; Wolf, A.P.; Langstrom, B.

    1990-04-03

    This invention involves a new strategy for imaging and mapping enzyme activity in the living human and animal body using positron emitter-labeled suicide enzyme inactivators or inhibitors which become covalently bound to the enzyme as a result of enzymatic catalysis. Two such suicide inactivators for monoamine oxidase have been labeled with carbon-11 and used to map the enzyme subtypes in the living human and animal body using PET. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography.

  8. Positron emitter labeled enzyme inhibitors

    DOEpatents

    Fowler, J.S.; MacGregor, R.R.; Wolf, A.P.

    1987-05-22

    This invention involved a new strategy for imaging and mapping enzyme activity in the living human and animal body using positron emitter-labeled suicide enzyme inactivators or inhibitors which become covalently bound to the enzyme as a result of enzymatic catalysis. Two such suicide in activators for monoamine oxidase have been labeled with carbon-11 and used to map the enzyme subtypes in the living human and animal body using PET. By using positron emission tomography to image the distribution of radioactivity produced by the body penetrating radiation emitted by carbon-11, a map of functionally active monoamine oxidase activity is obtained. Clorgyline and L-deprenyl are suicide enzyme inhibitors and irreversibly inhibit monoamine oxidase. When these inhibitors are labeled with carbon-11 they provide selective probes for monoamine oxidase localization and reactivity in vivo using positron emission tomography. 2 figs.

  9. Learning With Auxiliary Less-Noisy Labels.

    PubMed

    Duan, Yunyan; Wu, Ou

    2016-04-06

    Obtaining a sufficient number of accurate labels to form a training set for learning a classifier can be difficult due to the limited access to reliable label resources. Instead, in real-world applications, less-accurate labels, such as labels from nonexpert labelers, are often used. However, learning with less-accurate labels can lead to serious performance deterioration because of the high noise rate. Although several learning methods (e.g., noise-tolerant classifiers) have been advanced to increase classification performance in the presence of label noise, only a few of them take the noise rate into account and utilize both noisy but easily accessible labels and less-noisy labels, a small amount of which can be obtained with an acceptable added time cost and expense. In this brief, we propose a learning method, in which not only noisy labels but also auxiliary less-noisy labels, which are available in a small portion of the training data, are taken into account. Based on a flipping probability noise model and a logistic regression classifier, this method estimates the noise rate parameters, infers ground-truth labels, and learns the classifier simultaneously in a maximum likelihood manner. The proposed method yields three learning algorithms, which correspond to three prior knowledge states regarding the less-noisy labels. The experiments show that the proposed method is tolerant to label noise, and outperforms classifiers that do not explicitly consider the auxiliary less-noisy labels.

  10. Food labeling: gluten-free labeling of foods. Final rule.

    PubMed

    2013-08-05

    The Food and Drug Administration (FDA or we) is issuing a final rule to define the term "gluten-free'' for voluntary use in the labeling of foods. The final rule defines the term "gluten-free'' to mean that the food bearing the claim does not contain an ingredient that is a gluten-containing grain (e.g., spelt wheat); an ingredient that is derived from a gluten-containing grain and that has not been processed to remove gluten (e.g., wheat flour); or an ingredient that is derived from a gluten-containing grain and that has been processed to remove gluten (e.g., wheat starch), if the use of that ingredient results in the presence of 20 parts per million (ppm) or more gluten in the food (i.e., 20 milligrams (mg) or more gluten per kilogram (kg) of food); or inherently does not contain gluten; and that any unavoidable presence of gluten in the food is below 20 ppm gluten (i.e., below 20 mg gluten per kg of food). A food that bears the claim "no gluten,'' "free of gluten,'' or "without gluten'' in its labeling and fails to meet the requirements for a "gluten-free'' claim will be deemed to be misbranded. In addition, a food whose labeling includes the term "wheat'' in the ingredient list or in a separate "Contains wheat'' statement as required by a section of the Federal Food, Drug, and Cosmetic Act (the FD&C Act) and also bears the claim "gluten-free'' will be deemed to be misbranded unless its labeling also bears additional language clarifying that the wheat has been processed to allow the food to meet FDA requirements for a "gluten-free'' claim. Establishing a definition of the term "gluten-free'' and uniform conditions for its use in food labeling will help ensure that individuals with celiac disease are not misled and are provided with truthful and accurate information with respect to foods so labeled. We are issuing the final rule under the Food Allergen Labeling and Consumer Protection Act of 2004 (FALCPA).

  11. Test-retest reproducibility of binding parameters in humans with 11C-LY2795050, an antagonist PET radiotracer for the kappa opioid receptor

    PubMed Central

    Naganawa, Mika; Zheng, Ming-Qiang; Henry, Shannan; Nabulsi, Nabeel; Lin, Shu-Fei; Ropchan, Jim; Labaree, David; Najafzadeh, Soheila; Kapinos, Michael; Tauscher, Johannes; Neumeister, Alexander; Carson, Richard E.; Huang, Yiyun

    2015-01-01

    11C-LY2795050 is a new antagonist PET radioligand for the kappa opioid receptor (KOR). In this study, we assessed the reproducibility of the binding parameters of 11C-LY2795050 in healthy human subjects. Methods Sixteen healthy subjects (11 men, 5 women) underwent two separate 90-min PET scans with arterial input function and plasma free fraction measurements. The two-tissue compartment model and multilinear analysis-1 were applied to calculate five outcome measures in 14 brain regions: distribution volume (VT), distribution volume normalized by plasma free fraction (VT/fP), and three binding potentials (BPND, BPP, BPF). Since KOR is distributed ubiquitously throughout the brain, there are no suitable reference regions. We used a fixed fraction of individual cerebellum VT value as the non-displaceable distribution volume VND (= VT CER/1.17). The relative and absolute test-retest variability and intra-class correlation coefficient were evaluated for the outcome measures of 11C-LY2795050. Results The test-retest variability of 11C-LY2795050 for VT was ≤ 10% in all regions, and 12% in the amygdala. For binding potentials (BPND and BPP), the test-retest variability was good in regions of moderate and high KOR density (BPND > 0.4) and poor in regions of low density. Correction by fP (VT/fP or BPF) did not improve the test-retest performance. Conclusion Our results suggest that quantification of 11C-LY2795050 imaging is reproducible and reliable in the regions with moderate and high KOR density. Therefore we conclude that this first antagonist radiotracer is highly useful for PET studies of KOR. PMID:25593119

  12. Investigating the binding properties of porous drug delivery systems using nuclear sensors (radiotracers) and positron annihilation lifetime spectroscopy--predicting conditions for optimum performance.

    PubMed

    Mume, Eskender; Lynch, Daniel E; Uedono, Akira; Smith, Suzanne V

    2011-06-21

    Understanding how the size, charge and number of available pores in porous material influences the uptake and release properties is important for optimising their design and ultimately their application. Unfortunately there are no standard methods for screening porous materials in solution and therefore formulations must be developed for each encapsulated agent. This study investigates the potential of a library of radiotracers (nuclear sensors) for assessing the binding properties of hollow silica shell materials. Uptake and release of Cu(2+) and Co(2+) and their respective complexes with polyazacarboxylate macrocycles (dota and teta) and a series of hexa aza cages (diamsar, sarar and bis-(p-aminobenzyl)-diamsar) from the hollow silica shells was monitored using their radioisotopic analogues. Coordination chemistry of the metal (M) species, subtle alterations in the molecular architecture of ligands (Ligand) and their resultant complexes (M-Ligand) were found to significantly influence their uptake over pH 3 to 9 at room temperature. Positively charged species were selectively and rapidly (within 10 min) absorbed at pH 7 to 9. Negatively charged species were preferentially absorbed at low pH (3 to 5). Rates of release varied for each nuclear sensor, and time to establish equilibrium varied from minutes to days. The subtle changes in design of the nuclear sensors proved to be a valuable tool for determining the binding properties of porous materials. The data support the development of a library of nuclear sensors for screening porous materials for use in optimising the design of porous materials and the potential of nuclear sensors for high through-put screening of materials.

  13. Studies on the sorption and desorption characteristics of Zn(II) on the surface soils of nuclear power plant sites in India using a radiotracer technique.

    PubMed

    Dahiya, Sudhir; Shanwal, A V; Hegde, A G

    2005-09-01

    Zinc adsorption was studied in the soils of three nuclear power plant sites of India. 65Zn was used as a radiotracer to study the sorption characteristics of Zn(II). The sorption of zinc was determined at 25 and 45 degrees C at pH 7.8+/-0.2 in the solution of 0.01 M Ca(NO3)2 as supporting electrolyte. The sorption data was tested both in Freundlich and Langmuir isotherms and could be described satisfactorily. The effect of organic matter and other physico-chemical properties on the uptake of zinc was also studied in all the soil samples. The results showed that the cation exchange capacity, organic matter, pH and clay content were the main contributors to zinc sorption in these soils. The adsorption maximum was found to be higher in the soil on Kakarpara Atomic Power Plant sites soils having high organic matter and clay content. The zinc supply parameters of the soils are also discussed. In the desorption studies, the sequential extraction of the adsorbed zinc from soils showed that the diethylene triamine penta acetic acid extracted maximum amount of adsorbed zinc than CaCl2 and Mg(NO3)2. The zinc sorption on the soil and amount of zinc retention after extractants desorption shows a positively correlation with vermiculite and smectite mineral content present in the clay fraction of the soil. The amount desorbed by strong base (NaOH) and demineralised water was almost negligible from soils of all the sites, whereas the desorption by strong acid (HNO3) was 75-96% of the adsorbed zinc.

  14. A New Component Labelling And Merging Algorithm

    NASA Astrophysics Data System (ADS)

    Lochovsky, Amelia F.

    1987-10-01

    Component labelling is an important part of region analysis in image processing. Component labelling consists of assigning labels to pixels in the image such that adjacent pixels are given the same labels. There are various approaches to component labelling. Some require random access to the processed image; some assume special structure of the image such as a quad tree. Algorithms based on sequential scan of the image are attractive to hardware implementation. One method of labelling is based on a fixed size local window which includes the previous line. Due to the fixed size window and the sequential fashion of the labelling process, different branches of the same object may be given different labels and later found to be connected to each other. These labels are con-sidered to be equivalent and must later be collected to correctly represent one single object. This approach can be found in [F,FE,R]. Assume an input binary image of size NxM. Using these labelling algorithms, the number of equivalent pair generated is bounded by O(N*M). The number of distinct labels is also bounded by O(N*M). There is no known algorithm that merge the equivalent label pairs in time linear to the number of pairs, that is in time bounded by O(N*M). We propose a new labelling algorithm which interleaves the labelling with the merging process. The labelling and the merging are combined in one algorithm. Merged label information is kept in an equivalent table which is used to guide the labelling. In general , the algorithm produces fewer equivalent label pairs. The combined labelling and merging algorithm is O(N*M), where NxM is the size of the image. Section II describes the algorithm. Section III gives some examples We discuss implementation issues in section IV and further discussion and conclusion are given in Section V.

  15. Synthesis and Evaluation of Tricarbonyl 99mTc-Labeled 2-(4-Chloro)phenyl-imidazo[1,2-a]pyridine Analogs as Novel SPECT Imaging Radiotracer for TSPO-Rich Cancer

    PubMed Central

    Choi, Ji Young; Iacobazzi, Rosa Maria; Perrone, Mara; Margiotta, Nicola; Cutrignelli, Annalisa; Jung, Jae Ho; Park, Do Dam; Moon, Byung Seok; Denora, Nunzio; Kim, Sang Eun; Lee, Byung Chul

    2016-01-01

    The 18-kDa translocator protein (TSPO) levels are associated with brain, breast, and prostate cancer progression and have emerged as viable targets for cancer therapy and imaging. In order to develop highly selective and active ligands with a high affinity for TSPO, imidazopyridine-based TSPO ligand (CB256, 3) was prepared as the precursor. 99mTc- and Re-CB256 (1 and 2, respectively) were synthesized in high radiochemical yield (74.5% ± 6.4%, decay-corrected, n = 5) and chemical yield (65.6%) by the incorporation of the [99mTc(CO)3(H2O)3]+ and (NEt4)2[Re(CO)3Br3] followed by HPLC separation. Radio-ligand 1 was shown to be stable (>99%) when incubated in human serum for 4 h at 37 °C with a relatively low lipophilicity (logD = 2.15 ± 0.02). The rhenium-185 and -187 complex 2 exhibited a moderate affinity (Ki = 159.3 ± 8.7 nM) for TSPO, whereas its cytotoxicity evaluated on TSPO-rich tumor cell lines was lower than that observed for the precursor. In vitro uptake studies of 1 in C6 and U87-MG cells for 60 min was found to be 9.84% ± 0.17% and 7.87% ± 0.23% ID, respectively. Our results indicated that 99mTc-CB256 can be considered as a potential new TSPO-rich cancer SPECT imaging agent and provides the foundation for further in vivo evaluation. PMID:27399688

  16. How to read food labels

    MedlinePlus

    ... 24 liters) cooked. If you eat 2 cups (0.48 liters) at a meal, you are eating 2 servings. That is 2 times the amount of the calories, fats, and other items listed on the label. Calorie information tells you the number of calories in ...

  17. Revisiting Labels: "Hearing" or Not?

    ERIC Educational Resources Information Center

    Rhoades, Ellen A.

    2010-01-01

    This position paper briefly presents evidence-based findings pertaining to the language of labels for people with hearing loss that relate to stigma, expectation levels, stereotypes, and self-fulfilling prophecies. These constructs are important for auditory-based practitioners, administrators, policymakers, students, families, and persons with…

  18. When Diagnostic Labels Mask Trauma

    ERIC Educational Resources Information Center

    Foltz, Robert; Dang, Sidney; Daniels, Brian; Doyle, Hillary; McFee, Scott; Quisenberry, Carolyn

    2013-01-01

    A growing body of research shows that many seriously troubled children and adolescents are reacting to adverse life experiences. Yet traditional diagnostic labels are based on checklists of surface symptoms. Distracted by disruptive behavior, the common response is to medicate, punish, or exclude rather than respond to needs of youth who have…

  19. The Labelling Approach to Deviance.

    ERIC Educational Resources Information Center

    Rains, Prudence M.; Kitsuse, John L.; Duster, Troy; Freidson, Eliot

    2003-01-01

    This reprint of one chapter from the 1975 text, "Issues in the Classification of Children" by Nicholas Hobbs and others, addresses the theoretical, methodological, and empirical issues involved in the "labeling" approach to the sociology of deviance. It examines the social process of classification, the use of classification in social agencies,…

  20. Food Allergies: Understanding Food Labels

    MedlinePlus

    ... These eight foods are: Milk Eggs Peanuts Tree nuts (such as almonds, cashews, walnuts) Fish (such as bass, cod, flounder) Shellfish (such as crab, lobster, shrimp) Soy Wheat U.S. food labels take ... the type of tree nut (almond, walnut) or the type of crustacean shellfish ( ...

  1. Psychological effectiveness of carbon labelling

    NASA Astrophysics Data System (ADS)

    Beattie, Geoffrey

    2012-04-01

    Despite the decision by supermarket-giant Tesco to delay its plan to add carbon-footprint information onto all of its 70,000 products, carbon labelling, if carefully designed, could yet change consumer behaviour. However, it requires a new type of thinking about consumers and much additional work.

  2. Targeting of lacZ reporter gene expression with radioiodine-labelled phenylethyl-beta- d-thiogalactopyranoside.

    PubMed

    Lee, Kyung-Han; Byun, Sang Sung; Choi, Joon Hun; Paik, Jin-Young; Choe, Yearn Seong; Kim, Byung-Tae

    2004-03-01

    There has recently been increasing interest in the development of radioprobes that specifically target proteins transcribed from expression of reporter genes of interest. The purpose of this study was to develop a radioprobe that targets one of the most widely used reporter genes, the bacterial lacZ gene. We synthesised and purified radioiodine-labelled phenylethyl-beta- d-thiogalactopyranoside (PETG), a competitive inhibitor specific against Escherichia coli beta-galactosidase. We showed that [(125)I]iodo-PETG specifically binds to beta-galactosidase as verified by column chromatography and polyacrylamide gel electrophoresis after incubation of radiotracer with the protein. We also showed through enzyme kinetic studies that iodo-PETG retains inhibitory action against beta-galactosidase activity. COS-7 cells infected with a recombinant adenovirus expressing the lacZ gene had viral titre-dependent enhancements in [(125)I]iodo-PETG uptake ( r(2)=0.897; P=0.001), which reached up to 642.5%+/-16.7% of control levels ( P<0.00001). Moreover, the level of uptake was highly correlated to luminescent measurements of beta-galactosidase activity ( r(2)=0.878; P<0.0001). These results confirm that radioiodine-labelled PETG specifically targets beta-galactosidase and that its uptake rates faithfully reflect levels of expression of the lacZ reporter gene. Further investigations were performed in nude mice bearing human neuroblastoma tumours transferred with the lacZ gene. Compared with control tumours, lacZ-expressing tumours were slightly better visualised on [(123)I]iodo-PETG images and had a modest increase in tumour to muscle count ratio (2.6+/-0.2 vs 1.9+/-0.1, P<0.05). The present results provide proof-of-principle for the potential of radiolabelled inhibitors as promising radiotracers to monitor lacZ gene expression levels. Future modifications to improve cell permeability should enhance in vivo contrast levels and may allow the use of radiolabelled beta

  3. The labeling debate in the United States.

    PubMed

    Marchant, Gary E; Cardineau, Guy A

    2013-01-01

    The mandatory labeling of genetically modified (GM) food has become the predominant policy issue concerning biotechnology in the United States. The controversy over GM labeling is being debated at several different levels and branches of government. At the federal level, the Food and Drug Administration, which has primary jurisdiction over food safety and labeling, has steadfastly refused to require labeling of GM foods since 1992 based on its conclusion that GM foods as a category present no unique or higher risks than other foods. Proposed legislation has been repeatedly introduced in the US. Congress over the years to mandate GM labeling, but has made very little progress. With federal labeling requirements apparently stalled, the main activity has switched to the state level, where numerous individual states are considering mandatory GM labeling, either through legislation or proposition. The debate over GM labeling, at both the federal and state levels, has focused on five issues: (1) public opinion; (2) the legality of labeling requirements; (3) the risks and benefits of GM foods; (4) the costs and burdens of GM labeling; and (5) consumer choice. While the pro-labeling forces argue that all of these factors weigh in favor of mandatory GM labeling, a more careful evaluation of the evidence finds that all five factors weigh decisively against mandatory GM labeling requirements.

  4. 21 CFR 640.94 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma Protein Fraction (Human) § 640.94 Labeling. In addition... package labels shall contain the following information: (a) The osmotic equivalent in terms of plasma,...

  5. 21 CFR 640.94 - Labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma Protein Fraction (Human) § 640.94 Labeling. In addition... package labels shall contain the following information: (a) The osmotic equivalent in terms of plasma,...

  6. 21 CFR 640.94 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma Protein Fraction (Human) § 640.94 Labeling. In addition... package labels shall contain the following information: (a) The osmotic equivalent in terms of plasma,...

  7. 21 CFR 640.94 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma Protein Fraction (Human) § 640.94 Labeling. In addition... package labels shall contain the following information: (a) The osmotic equivalent in terms of plasma,...

  8. 21 CFR 640.94 - Labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Plasma Protein Fraction (Human) § 640.94 Labeling. In addition... package labels shall contain the following information: (a) The osmotic equivalent in terms of plasma,...

  9. 21 CFR 640.84 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Albumin (Human) § 640.84 Labeling. In addition to the labeling... percent albumin is administered to a patient with marked dehydration; (d) The protein...

  10. 21 CFR 640.84 - Labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Albumin (Human) § 640.84 Labeling. In addition to the labeling... percent albumin is administered to a patient with marked dehydration; (d) The protein...

  11. 21 CFR 640.84 - Labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Albumin (Human) § 640.84 Labeling. In addition to the labeling... percent albumin is administered to a patient with marked dehydration; (d) The protein...

  12. 21 CFR 640.84 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Albumin (Human) § 640.84 Labeling. In addition to the labeling... percent albumin is administered to a patient with marked dehydration; (d) The protein...

  13. 21 CFR 640.84 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Albumin (Human) § 640.84 Labeling. In addition to the labeling... percent albumin is administered to a patient with marked dehydration; (d) The protein...

  14. Soil Fumigant Labels - Metam Sodium/Potassium

    EPA Pesticide Factsheets

    Search by EPA registration number, product name, or company; and follow the link to the Pesticide Product Label System (PPLS) for details. Updated labels include new safety requirements for buffer zones and related measures.

  15. Logos and Graphics on Pesticide Product Labels

    EPA Pesticide Factsheets

    There are several logos that pesticide companies can add to their labels with EPA approval. The requirements and process vary, so review the guidance carefully before applying to add a logo to a product label.

  16. 40 CFR 205.158 - Labeling requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... color that contrasts with the background of the label. (5) The label must contain the following... Califfo CAL Carabela CAR Cimatti CIM Columbia COL E-Z Rider EZR Flying Dutchman FLY Foxi FOI Gadabout...

  17. 40 CFR 205.158 - Labeling requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... color that contrasts with the background of the label. (5) The label must contain the following... Califfo CAL Carabela CAR Cimatti CIM Columbia COL E-Z Rider EZR Flying Dutchman FLY Foxi FOI Gadabout...

  18. 40 CFR 205.158 - Labeling requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... color that contrasts with the background of the label. (5) The label must contain the following... Califfo CAL Carabela CAR Cimatti CIM Columbia COL E-Z Rider EZR Flying Dutchman FLY Foxi FOI Gadabout...

  19. 40 CFR 262.31 - Labeling.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Pre-Transport Requirements § 262.31 Labeling. Before transporting or offering hazardous waste for transportation off-site, a generator must label each package...

  20. 40 CFR 262.31 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Pre-Transport Requirements § 262.31 Labeling. Before transporting or offering hazardous waste for transportation off-site, a generator must label each package...

  1. 40 CFR 262.31 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Pre-Transport Requirements § 262.31 Labeling. Before transporting or offering hazardous waste for transportation off-site, a generator must label each package...

  2. 40 CFR 262.31 - Labeling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Pre-Transport Requirements § 262.31 Labeling. Before transporting or offering hazardous waste for transportation off-site, a generator must label each package...

  3. 40 CFR 262.31 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... APPLICABLE TO GENERATORS OF HAZARDOUS WASTE Pre-Transport Requirements § 262.31 Labeling. Before transporting or offering hazardous waste for transportation off-site, a generator must label each package...

  4. 99mTc: Labeling Chemistry and Labeled Compounds

    NASA Astrophysics Data System (ADS)

    Alberto, R.; Abram, U.

    This chapter reviews the radiopharmaceutical chemistry of technetium related to the synthesis of perfusion agents and to the labeling of receptor-binding biomolecules. To understand the limitations of technetium chemistry imposed by future application of the complexes in nuclear medicine, an introductory section analyzes the compulsory requirements to be considered when facing the incentive of introducing a novel radiopharmaceutical into the market. Requirements from chemistry, routine application, and market are discussed. In a subsequent section, commercially available 99mTc-based radiopharmaceuticals are treated. It covers the complexes in use for imaging the most important target organs such as heart, brain, or kidney. The commercially available radiopharmaceuticals fulfill the requirements outlined earlier and are discussed with this background. In a following section, the properties and perspectives of the different generations of radiopharmaceuticals are described in a general way, covering characteristics for perfusion agents and for receptor-specific molecules. Technetium chemistry for the synthesis of perfusion agents and the different labeling approaches for target-specific biomolecules are summarized. The review comprises a general introduction to the common approaches currently in use, employing the N x S4-x , [3+1] and 2-hydrazino-nicotinicacid (HYNIC) method as well as more recent strategies such as the carbonyl and the TcN approach. Direct labeling without the need of a bifunctional chelator is briefly reviewed as well. More particularly, recent developments in the labeling of concrete targeting molecules, the second generation of radiopharmaceuticals, is then discussed and prominent examples with antibodies/peptides, neuroreceptor targeting small molecules, myocardial imaging agents, vitamins, thymidine, and complexes relevant to multidrug resistance are given. In addition, a new approach toward peptide drug development is described. The section

  5. Fluorescently labelled glycans and their applications.

    PubMed

    Yan, Hongbin; Yalagala, Ravi Shekar; Yan, Fengyang

    2015-11-01

    This review summarises the literature on the synthesis and applications of fluorescently labelled carbohydrates. Due to the sensitivity of fluorescent detection, this approach provides a useful tool to study processes involving glycans. A few general categories of labelling are presented, in situ labelling of carbohydrates with fluorophores, fluorescently labelled glycolipids, fluorogenic glycans, pre-formed fluorescent glycans for intracellular applications, glycan-decorated fluorescent polymers, fluorescent glyconanoparticles, and other functional fluorescent glycans.

  6. White Label Space GLXP Mission

    NASA Astrophysics Data System (ADS)

    Barton, A.

    2012-09-01

    This poster presents a lunar surface mission concept and corresponding financing approach developed by the White Label Space team, an official competitor in the Google Lunar X PRIZE. The White Label Space team's origins were in the European Space Agency's ESTEC facility in the Netherlands. Accordingly the team's technical headquarters are located just outside ESTEC in the Space Business Park. The team has active partners in Europe, Japan and Australia. The team's goal is to provide a unique publicity opportunity for global brands to land on the moon and win the prestigious Google Lunar X PRIZE. The poster presents the main steps to achieve this goal, the cost estimates for the mission, describes the benefits to the potential sponsors and supporters, and details the progress achieved to date.

  7. Automated labeling in document images

    NASA Astrophysics Data System (ADS)

    Kim, Jongwoo; Le, Daniel X.; Thoma, George R.

    2000-12-01

    The National Library of Medicine (NLM) is developing an automated system to produce bibliographic records for its MEDLINER database. This system, named Medical Article Record System (MARS), employs document image analysis and understanding techniques and optical character recognition (OCR). This paper describes a key module in MARS called the Automated Labeling (AL) module, which labels all zones of interest (title, author, affiliation, and abstract) automatically. The AL algorithm is based on 120 rules that are derived from an analysis of journal page layouts and features extracted from OCR output. Experiments carried out on more than 11,000 articles in over 1,000 biomedical journals show the accuracy of this rule-based algorithm to exceed 96%.

  8. Labeling nuclear DNA using DAPI.

    PubMed

    Chazotte, Brad

    2011-01-01

    A number of fluorescent stains are available that label DNA and allow easy visualization of the nucleus in interphase cells and chromosomes in mitotic cells, including Hoechst, 4',6-diamidino-2-phenylindole (DAPI), ethidium bromide, propidium iodide, and acridine orange. Although not as bright as the vital Hoechst stains for DNA, DAPI has greater photostability. It is believed that DAPI associates with the minor groove of double-stranded DNA, with a preference for the adenine-thymine clusters. Cells must be permeabilized and/or fixed for DAPI to enter the cell and to bind DNA. Fluorescence increases approximately 20-fold when DAPI is bound to double-stranded DNA. This protocol describes the use of DAPI to label nuclear DNA of cells grown in culture.

  9. A systematic comparison of 18F-C-SNAT to established radiotracer imaging agents for the detection of tumor response to treatment

    PubMed Central

    Witney, Timothy H; Hoehne, Aileen; Reeves, Robert E; Ilovich, Ohad; Namavari, Mohammad; Shen, Bin; Chin, Frederick T; Rao, Jianghong; Gambhir, Sanjiv S

    2015-01-01

    Purpose An early readout of tumor response to therapy through measurement of drug or radiation-induced cell death may provide important prognostic indications and improved patient management. It has been shown that the uptake of 18F-C-SNAT can be used to detect early response to therapy in tumors by positron emission tomography via a mechanism of caspase 3-triggered nanoaggregation. Experimental Design Here, we compared the preclinical utility of 18F-C-SNAT for the detection of drug-induced cell death to clinically evaluated radiotracers, 18F-FDG, 99mTc-Annexin V and 18F-ML-10 in tumor cells in culture, and in tumor-bearing mice in vivo. Results In drug-treated lymphoma cells, 18F-FDG, 99mTc-Annexin V and 18F-C-SNAT cell-associated radioactivity correlated well to levels of cell death (R2 > 0.8; P < 0.001), with no correlation measured for 18F-ML-10 (R2 = 0.05; P > 0.05). A similar pattern of response was observed in two human NSCLC cell lines following carboplatin treatment. EL-4 tumor uptake of 99mTc-Annexin V and 18F-C-SNAT were increased 1.4- and 2.1-fold, respectively in drug-treated versus naïve control animals (P < 0.05), although 99mTc-Annexin V binding did not correlate to ex vivo TUNEL staining of tissue sections. A differential response was not observed with either 18F-FDG or 18F-ML-10. Conclusions We have demonstrated here that 18F-C-SNAT can sensitively detect drug-induced cell death in murine lymphoma and human NSCLC. Despite favorable image contrast obtained with 18F-C-SNAT, the development of next generation derivatives, using the same novel and promising uptake mechanism, but displaying improved biodistribution profiles, are warranted for maximum clinical utility. PMID:25972517

  10. Evaluation of [(18) F]BR420 and [(18) F]BR351 as radiotracers for MMP-9 imaging in colorectal cancer.

    PubMed

    Vazquez, Naiara; Missault, Stephan; Vangestel, Christel; Deleye, Steven; Thomae, David; Van der Veken, Pieter; Augustyns, Koen; Staelens, Steven; Dedeurwaerdere, Stefanie; Wyffels, Leonie

    2017-01-01

    MMP-9 is a zinc-dependent endopeptidase that is involved in the proteolytic degradation of the extracellular matrix and plays an important role in cancer migration, invasion, and metastasis. The aim of this study was to evaluate the potential of MMP-tracers [(18) F]BR420 and [(18) F]BR351 for MMP-9 imaging in a colorectal cancer xenograft model. [(18) F]BR420 and [(18) F]BR351 were synthesized using an automated synthesis module. For [(18) F]BR420, a novel and improved radiosynthesis was developed. Plasma stability and MMP-9-targeting capacity of both radiotracers was compared in the Colo205 colorectal cancer model. MMP-9 and MMP-2 expression levels in the tumors were evaluated by immunohistochemistry and in situ zymography. μPET imaging as well as ex vivo biodistribution revealed a higher tumor uptake for [(18) F]BR420 (3.15% ± 0.03% ID/g vs 0.94% ± 0.18% ID/g for [(18) F]BR351 at 2 hours pi) but slower blood clearance compared with [(18) F]BR351. [(18) F]BR351 was quickly metabolized in plasma with 20.28% ± 5.41% of intact tracer remaining at 15 minutes postinjection (PI). By contrast, [(18) F]BR420 displayed a higher metabolic stability with >86% intact tracer remaining at 2 hours PI. Immunohistochemistry revealed the presence of MMP-9 and MMP-2 in the tumor tissue, which was confirmed by in situ zymography. However, an autoradiography analysis of tracer distribution in the tumors did not correlate with MMP-9 expression. [(18) F]BR420 displayed a higher tumor uptake and higher stability compared with [(18) F]BR351 but a low tumor-to-blood ratio and discrepancy between tracer distribution and MMP-9 immunohistochemistry. Therefore, both tracers will not be usefulness for MMP-9 imaging in colorectal cancer.

  11. 21 CFR 820.120 - Device labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Device labeling. 820.120 Section 820.120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES QUALITY SYSTEM REGULATION Labeling and Packaging Control § 820.120 Device labeling. Each...

  12. Labeling Nodes Using Three Degrees of Propagation

    PubMed Central

    Mostafavi, Sara; Goldenberg, Anna; Morris, Quaid

    2012-01-01

    The properties (or labels) of nodes in networks can often be predicted based on their proximity and their connections to other labeled nodes. So-called “label propagation algorithms” predict the labels of unlabeled nodes by propagating information about local label density iteratively through the network. These algorithms are fast, simple and scale to large networks but nonetheless regularly perform better than slower and much more complex algorithms on benchmark problems. We show here, however, that these algorithms have an intrinsic limitation that prevents them from adapting to some common patterns of network node labeling; we introduce a new algorithm, 3Prop, that retains all their advantages but is much more adaptive. As we show, 3Prop performs very well on node labeling problems ill-suited to label propagation, including predicting gene function in protein and genetic interaction networks and gender in friendship networks, and also performs slightly better on problems already well-suited to label propagation such as labeling blogs and patents based on their citation networks. 3Prop gains its adaptability by assigning separate weights to label information from different steps of the propagation. Surprisingly, we found that for many networks, the third iteration of label propagation receives a negative weight. Availability The code is available from the authors by request. PMID:23284828

  13. Learning Words from Labeling and Directive Speech

    ERIC Educational Resources Information Center

    Callanan, Maureen A.; Akhtar, Nameera; Sussman, Lisa

    2014-01-01

    Despite the common intuition that labeling may be the best way to teach a new word to a child, systematic testing is needed of the prediction that children learn words better from labeling utterances than from directive utterances. Two experiments compared toddlers' label learning in the context of hearing words used in directive versus labeling…

  14. 21 CFR 660.35 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.35 Labeling. In... or end of the label, oustide of the main panel. (2) If washing the cells is required by the manufacturer, the container label shall include appropriate instructions; if the cells should not be...

  15. 21 CFR 660.35 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.35 Labeling. In... or end of the label, oustide of the main panel. (2) If washing the cells is required by the manufacturer, the container label shall include appropriate instructions; if the cells should not be...

  16. 49 CFR 172.426 - OXIDIZER label.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.426 OXIDIZER label. (a) Except for size and color, the OXIDIZER label must be as follows: EC02MR91.027 (b) In addition to complying with § 172.407, the background color on...

  17. 49 CFR 172.426 - OXIDIZER label.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.426 OXIDIZER label. (a) Except for size and color, the OXIDIZER label must be as follows: EC02MR91.027 (b) In addition to complying with § 172.407, the background color on...

  18. 49 CFR 172.441 - FISSILE label.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.441 FISSILE label. (a) Except for size and color, the FISSILE label must be as follows: ER26ja04.000 (b) In addition to complying with § 172.407, the background color on...

  19. 49 CFR 172.426 - OXIDIZER label.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.426 OXIDIZER label. (a) Except for size and color, the OXIDIZER label must be as follows: EC02MR91.027 (b) In addition to complying with § 172.407, the background color on...

  20. 49 CFR 172.426 - OXIDIZER label.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.426 OXIDIZER label. (a) Except for size and color, the OXIDIZER label must be as follows: EC02MR91.027 (b) In addition to complying with § 172.407, the background color on...

  1. 49 CFR 172.441 - FISSILE label.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.441 FISSILE label. (a) Except for size and color, the FISSILE label must be as follows: ER26ja04.000 (b) In addition to complying with § 172.407, the background color on...

  2. 49 CFR 172.441 - FISSILE label.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.441 FISSILE label. (a) Except for size and color, the FISSILE label must be as follows: ER26ja04.000 (b) In addition to complying with § 172.407, the background color on...

  3. 49 CFR 172.441 - FISSILE label.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS HAZARDOUS MATERIALS TABLE, SPECIAL... SECURITY PLANS Labeling § 172.441 FISSILE label. (a) Except for size and color, the FISSILE label must be as follows: ER26ja04.000 (b) In addition to complying with § 172.407, the background color on...

  4. 40 CFR 211.105 - Label format.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Label format. 211.105 Section 211.105 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) NOISE ABATEMENT PROGRAMS PRODUCT NOISE LABELING General Provisions § 211.105 Label format. (a) Unless specified otherwise in other...

  5. 16 CFR 306.12 - Labels.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    .... All type is centered. The band at the top of the label contains either: (A) The capital letter “B... at the top of the label shall contain the capital letter “B” followed immediately by the numerical... the black band at the top of the label shall contain the phrase “B-100 Biodiesel.” In addition,...

  6. 21 CFR 660.28 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... panel. Blood grouping reagent Color of label paper Anti-A Blue. Anti-B Yellow. Slide and rapid tube test... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.28 Labeling. In... label—(1) Color coding. The final container label of all Blood Grouping Reagents shall be...

  7. 21 CFR 660.28 - Labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... panel. Blood grouping reagent Color of label paper Anti-A Blue. Anti-B Yellow. Slide and rapid tube test... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.28 Labeling. In... label—(1) Color coding. The final container label of all Blood Grouping Reagents shall be...

  8. 21 CFR 660.28 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... panel. Blood grouping reagent Color of label paper Anti-A Blue. Anti-B Yellow. Slide and rapid tube test... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.28 Labeling. In... label—(1) Color coding. The final container label of all Blood Grouping Reagents shall be...

  9. 21 CFR 660.28 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... panel. Blood grouping reagent Color of label paper Anti-A Blue. Anti-B Yellow. Slide and rapid tube test... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.28 Labeling. In... label—(1) Color coding. The final container label of all Blood Grouping Reagents shall be...

  10. 21 CFR 660.28 - Labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... panel. Blood grouping reagent Color of label paper Anti-A Blue. Anti-B Yellow. Slide and rapid tube test... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Blood Grouping Reagent § 660.28 Labeling. In... label—(1) Color coding. The final container label of all Blood Grouping Reagents shall be...

  11. 75 FR 81943 - Appliance Labeling Rule

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-29

    ... comment. SUMMARY: The Commission proposes changing the effective date for its new light bulb labeling... the new label for incandescent bulbs (e.g., 75 watt bulbs) that, as of 2013, will not meet federal... current labeling requirements for ``lamps,'' commonly referred to as light bulbs, and alternative...

  12. 76 FR 20233 - Appliance Labeling Rule

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-12

    ...). ACTION: Final rule. SUMMARY: The Commission extends the effective date for its new light bulb labeling... Commission exempts from the new label requirements incandescent bulbs that will not be produced after January... proposing to extend the effective date of new labeling rules for light bulbs to January 1, 2012.\\1\\ The...

  13. 30 CFR 47.43 - Label alternatives.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Label alternatives. 47.43 Section 47.43 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.43 Label alternatives. The operator...

  14. 30 CFR 47.43 - Label alternatives.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Label alternatives. 47.43 Section 47.43 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.43 Label alternatives. The operator...

  15. 30 CFR 47.43 - Label alternatives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Label alternatives. 47.43 Section 47.43 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.43 Label alternatives. The operator...

  16. 30 CFR 47.43 - Label alternatives.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Label alternatives. 47.43 Section 47.43 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR EDUCATION AND TRAINING HAZARD COMMUNICATION (HazCom) Container Labels and Other Forms of Warning § 47.43 Label alternatives. The operator...

  17. 40 CFR 600.301 - Labeling requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Fuel Economy Labeling § 600.301 Labeling... each dealer shall maintain or cause to be maintained on each automobile: (1) A general fuel economy... vehicle for which a specific label is requested which has a combined FTP/HFET-based fuel economy value,...

  18. 21 CFR 1271.250 - Labeling controls.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Labeling controls. 1271.250 Section 1271.250 Food..., AND CELLULAR AND TISSUE-BASED PRODUCTS Current Good Tissue Practice § 1271.250 Labeling controls. (a) General. You must establish and maintain procedures to control the labeling of HCT/Ps. You must...

  19. 21 CFR 1271.250 - Labeling controls.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Labeling controls. 1271.250 Section 1271.250 Food..., AND CELLULAR AND TISSUE-BASED PRODUCTS Current Good Tissue Practice § 1271.250 Labeling controls. (a) General. You must establish and maintain procedures to control the labeling of HCT/Ps. You must...

  20. 21 CFR 1271.250 - Labeling controls.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Labeling controls. 1271.250 Section 1271.250 Food..., AND CELLULAR AND TISSUE-BASED PRODUCTS Current Good Tissue Practice § 1271.250 Labeling controls. (a) General. You must establish and maintain procedures to control the labeling of HCT/Ps. You must...

  1. 16 CFR 305.17 - Television labeling.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... DISCLOSURES REGARDING ENERGY CONSUMPTION AND WATER USE OF CERTAIN HOME APPLIANCES AND OTHER PRODUCTS REQUIRED UNDER THE ENERGY POLICY AND CONSERVATION ACT (âAPPLIANCE LABELING RULEâ) Required Disclosures § 305.17... manufacturer may include the ENERGY STAR logo on the label as illustrated in Sample Labels 10, 11, and 12...

  2. Labels and Children's Perceptions of Faces

    ERIC Educational Resources Information Center

    Katz, Phyllis A.; Seavey, Carol

    1973-01-01

    The relation between type of label and perception of faces was assessed in second- and sixth-grade children. Labels associated with color increased color perception, whereas labels based on expressiveness increased differentiation of expression variations, but not color perception. (ST)

  3. 21 CFR 820.120 - Device labeling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Device labeling. 820.120 Section 820.120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES QUALITY SYSTEM REGULATION Labeling and Packaging Control § 820.120 Device labeling. Each...

  4. 16 CFR 1633.12 - Labeling.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY (OPEN FLAME) OF MATTRESS SETS Rules and Regulations § 1633.12 Labeling. (a) Each mattress set subject to the Standard shall bear a permanent, conspicuous, and legible label(s) containing the...

  5. 16 CFR 1633.12 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY (OPEN FLAME) OF MATTRESS SETS Rules and Regulations § 1633.12 Labeling. (a) Each mattress set subject to the Standard shall bear a permanent, conspicuous, and legible label(s) containing the...

  6. 16 CFR 1633.12 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY (OPEN FLAME) OF MATTRESS SETS Rules and Regulations § 1633.12 Labeling. (a) Each mattress set subject to the Standard shall bear a permanent, conspicuous, and legible label(s) containing the...

  7. 40 CFR 94.212 - Labeling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... EMISSIONS FROM MARINE COMPRESSION-IGNITION ENGINES Certification Provisions § 94.212 Labeling. (a) General... new marine engine modified from a base engine by post-manufacture marinizers in accordance with the... shall be of a color that contrasts with the background of the label: (1) The label heading:...

  8. 21 CFR 660.35 - Labeling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Reagent Red Blood Cells § 660.35 Labeling. In... or end of the label, oustide of the main panel. (2) If washing the cells is required by the manufacturer, the container label shall include appropriate instructions; if the cells should not be...

  9. Do nutrition labels improve dietary outcomes?

    PubMed

    Variyam, Jayachandran N

    2008-06-01

    The disclosure of nutritional characteristics of most packaged foods became mandatory in the United States with the implementation of the Nutrition Labeling and Education Act (NLEA) in 1994. Under the NLEA regulations, a 'Nutrition Facts' panel displays information on nutrients such as calories, total and saturated fats, cholesterol, and sodium in a standardized format. By providing nutrition information in a credible, distinctive, and easy-to-read format, the new label was expected to help consumers choose healthier, more nutritious diets. This paper examines whether the disclosure of nutrition information through the mandatory labels impacted consumer diets. Assessing the dietary effects of labeling is problematic due to the confounding of the label effect with unobserved label user characteristics. This self-selection problem is addressed by exploiting the fact that the NLEA exempts away-from-home foods from mandatory labeling. Difference-in-differences models that account for zero away-from-home intakes suggest that the labels increase fiber and iron intakes of label users compared with label nonusers. In comparison, a model that does not account for self-selection implies significant label effects for all but two of the 13 nutrients that are listed on the label.

  10. 21 CFR 820.120 - Device labeling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Device labeling. 820.120 Section 820.120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES... shall establish and maintain procedures to control labeling activities. (a) Label integrity....

  11. 9 CFR 354.73 - Retention labels.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 9 Animals and Animal Products 2 2012-01-01 2012-01-01 false Retention labels. 354.73 Section 354.73 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... § 354.73 Retention labels. An inspector may use such labels, devices, and methods as may be approved...

  12. 9 CFR 354.73 - Retention labels.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 2 2011-01-01 2011-01-01 false Retention labels. 354.73 Section 354.73 Animals and Animal Products FOOD SAFETY AND INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE AGENCY... § 354.73 Retention labels. An inspector may use such labels, devices, and methods as may be approved...

  13. 21 CFR 1271.250 - Labeling controls.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Labeling controls. 1271.250 Section 1271.250 Food..., AND CELLULAR AND TISSUE-BASED PRODUCTS Current Good Tissue Practice § 1271.250 Labeling controls. (a) General. You must establish and maintain procedures to control the labeling of HCT/Ps. You must...

  14. Isotope Labeling in Insect Cells

    PubMed Central

    Saxena, Krishna; Dutta, Arpana; Klein-Seetharaman, Judith

    2011-01-01

    Recent years have seen remarkable progress in applying nuclear magnetic resonance (NMR) spectroscopy to proteins that have traditionally been difficult to study due to issues with folding, posttranslational modification, and expression levels or combinations thereof. In particular, insect cells have proved useful in allowing large quantities of isotope-labeled, functional proteins to be obtained and purified to homogeneity, allowing study of their structures and dynamics by using NMR. Here, we provide protocols that have proven successful in such endeavors. PMID:22167667

  15. CD-ROM Labeling Techniques

    DTIC Science & Technology

    1992-01-06

    was allowed to dry thoroughly before application to the disc, so that the solvent used would have dispersed. Use of this, or any adhesive is risky if...the chemical composition and solvents used are not known. Some acid based adhesives have been reported to have eaten through the disc’s protective...been specially manufactured with suitable adhesive ( beeswax ) for use with CD-ROM. Both foils can be printed with customer-labeled, generic

  16. 78 FR 24211 - Draft Guidance for Industry on Safety Considerations for Container Labels and Carton Labeling...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-24

    ... Container Labels and Carton Labeling Design To Minimize Medication Errors; Availability AGENCY: Food and... Labels and Carton Labeling Design to Minimize Medication Errors.'' The draft guidance focuses on safety... use of the product to minimize medication errors. DATES: Although you can comment on any guidance...

  17. 40 CFR 60.536 - Permanent label, temporary label, and owner's manual.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Permanent label, temporary label, and owner's manual. 60.536 Section 60.536 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Performance for New Residential Wood Heaters § 60.536 Permanent label, temporary label, and owner's manual....

  18. 40 CFR 60.536 - Permanent label, temporary label, and owner's manual.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 7 2013-07-01 2013-07-01 false Permanent label, temporary label, and owner's manual. 60.536 Section 60.536 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Performance for New Residential Wood Heaters § 60.536 Permanent label, temporary label, and owner's manual....

  19. 40 CFR 60.536 - Permanent label, temporary label, and owner's manual.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Permanent label, temporary label, and owner's manual. 60.536 Section 60.536 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Performance for New Residential Wood Heaters § 60.536 Permanent label, temporary label, and owner's manual....

  20. 40 CFR 60.536 - Permanent label, temporary label, and owner's manual.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Permanent label, temporary label, and owner's manual. 60.536 Section 60.536 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Performance for New Residential Wood Heaters § 60.536 Permanent label, temporary label, and owner's manual....

  1. 40 CFR 60.536 - Permanent label, temporary label, and owner's manual.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Permanent label, temporary label, and owner's manual. 60.536 Section 60.536 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Performance for New Residential Wood Heaters § 60.536 Permanent label, temporary label, and owner's manual....

  2. Abandoning a label doesn’t make it disappear: The perseverance of labeling effects

    PubMed Central

    Foroni, Francesco; Rothbart, Myron

    2012-01-01

    Labels exert strong influence on perception and judgment. The present experiment examines the possibility that such effects may persist even when labels are abandoned. Participants judged the similarity of pairs of silhouette drawings of female body types, ordered on a continuum from very thin to very heavy, under conditions where category labels were, and were not, superimposed on the ordered stimuli. Consistent with earlier research, labels had strong effects on perceived similarity, with silhouettes sharing the same label judged as more similar than those having different labels. Moreover, when the labels were removed and no longer present, the effect of the labels, although diminished, persisted. It did not make any difference whether the labels were simply abandoned or, in addition, had their validity challenged. The results are important for our understanding of categorization and labeling processes. The potential theoretical and practical implications of these results for social processes are discussed. PMID:23105148

  3. Stigma of a label: educational expectations for high school students labeled with learning disabilities.

    PubMed

    Shifrer, Dara

    2013-01-01

    Poorer outcomes for youth labeled with learning disabilities (LDs) are often attributed to the student's own deficiencies or cumulative disadvantage; but the more troubling possibility is that special education placement limits rather than expands these students' opportunities. Labeling theory partially attributes the poorer outcomes of labeled persons to stigma related to labels. This study uses data on approximately 11,740 adolescents and their schools from the Education Longitudinal Survey of 2002 to determine if stigma influences teachers' and parents' educational expectations for students labeled with LDs and labeled adolescents' expectations for themselves. Supporting the predictions of labeling theory, teachers and parents are more likely to perceive disabilities in, and hold lower educational expectations for labeled adolescents than for similarly achieving and behaving adolescents not labeled with disabilities. The negative effect of being labeled with LDs on adolescents' educational expectations is partially mechanized through parents' and particularly teachers' lower expectations.

  4. Evaluation of [111In]-Labeled Zinc-Dipicolylamine Tracers for SPECT Imaging of Bacterial Infection

    PubMed Central

    Rice, Douglas R.; Plaunt, Adam J.; Turkyilmaz, Serhan; Smith, Miles; Wang, Yuzhen; Rusckowski, Mary

    2015-01-01

    Purpose This study prepared three structurally related zinc-dipicolylamine (ZnDPA) tracers with [111In] labels and conducted biodistribution and SPECT/CT imaging studies of a mouse leg infection model. Methods Two monovalent tracers, ZnDPA-[111In]DTPA and ZnDPA-[111In]DOTA, each with a single zinc-dipicolylamine targeting unit, and a divalent tracer, Bis(ZnDPA)-[111In]DTPA,with two zinc-dipicolylamine units were prepared. Organ biodistribution and SPECT/CT imaging studies were performed on living mice with a leg infection created by injection of clinically relevant Gram positive Streptococcus pyogenes. Fluorescent and luminescent Eu3+-labeled versions of these tracers were also prepared and used to measure relative affinity for the exterior membrane surface of bacterial cells and mimics of healthy mammalian cells. Results All three 111In-labeled radiotracers were prepared with radiopurity > 90%. The biodistribution studies showed that the two monovalent tracers were cleared from the body through the liver and kidney, with retained % injected dose for all organs of < 8 % at 20 hours and infected leg T/NT ratio of ≤ 3.0. Clearance of the divalent tracer from the bloodstream was slower and primarily through the liver, with a retained % injected dose for all organs < 37% at 20 hours and T/NT ratio rising to 6.2 after 20 hours. The SPECT/CT imaging indicated the same large difference in tracer pharmacokinetics and higher accumulation of the divalent tracer at the site of infection. Conclusions All three [111In]-ZnDPA tracers selectively targeted the site of a clinically relevant mouse infection model that could not be discerned by visual external inspection of the living animal. The highest target selectivity, observed with a divalent tracer equipped with two zinc-dipicolylamine targeting units, compares quite favorably with the imaging selectivities previously reported for other nuclear tracers that target bacterial cell surfaces. The tracer pharmacokinetics depended

  5. Reduction of β-radiation exposure during preparation of 188Re-labelled Lipiodol for hepatocellular carcinoma treatment.

    PubMed

    Lepareur, Nicolas; Laffont, Sophie; Ardisson, Valérie; Noiret, Nicolas; Garin, Etienne

    2012-02-01

    Rhenium-188 (188Re) is of widespread interest for treating various diseases because of its attractive physical and chemical properties. The routine preparation of therapeutic doses of 188Re-labelled tracers can result in significant radiation exposure to the operator. We studied the impact of automating the preparation of 188Re-Lipiodol on the radiochemist's exposure, as well as the importance of the model of syringe shielding. To monitor radiation exposure continuously readable electronic personal dosimeters were used. Thermoluminescence dosimeters were fixed to the probable most exposed fingers of the radiochemist during preparation of the radiotracer and during the syringing. Dose rates were measured using a Babyline. Automation of the synthesis reduced personal dose equivalents from 2.60±4.35 to 1.61±1.20 µSv/GBq [Hp(10)] and from 38.37±55.28 to 21.84±16.14 µSv/GBq [Hp(0.07)]. Dose to the extremities was also reduced (-80% for the right hand; -58% for the left one). The Lemer-Pax PSWG syringe shield led to a slightly lower dose to the hands compared with the Medisystem (1.1±0.27 vs. 1.34±0.6 mSv/GBq for the right finger). Automation of the synthesis leads to a significant decrease in radiation exposure to the operator. The Lemer-Pax PSWG syringe shield provides better hand protection than the smaller Medisystem Mediclic.

  6. Human absorbed dose calculations for iodine-131 and iodine-123 labeled meta-iodobenzyl-guanidine (mIBG): a potential myocardial and adrenal medulla imaging agent

    SciTech Connect

    Swanson, D.P.; Carey, J.E.; Brown, L.E.; Kline, R.C.; Wieland, D.M.; Thrall, J.H.; Beierwaltes, W.H.

    1981-06-01

    Tissue distribution studies with radiolabeled meta-iodobenzyl-guanidine (mIBG), an analog of the adrenergic neuronal blocking agent-guanethidine, suggest that this radiotracer may be useful for both myocardial imaging (labeled with I-123) and adrenal medulla imaging (labeled with I-131). Total body elimination was determined by whole body counting (well-type ionization chamber) of rats administered /sup 131/I-mIBG and time-activity tissue distribution data was obtained in dogs using /sup 125/I-mIBG. Using the MIRD formalism, researchers have estimated the human absorbed dose from /sup 131/I-mIBG, radionuclidically pure /sup 123/I-mIBG, and /sup 1/''/sup 3/I-mIBG contaminated with 4.8% /sup 125/I-mIBG (based on /sup 123/I radionuclidic purity specification of 1.4% I-125 at calibration). The largest absorbed dose from /sup 131/I-mIBG was delivered to the adrenals. For pure /sup 123/I-mIBG the largest absorbed dose was delivered to the thyroid (unblocked). The /sup 125/I contamination increased the absorbed dose to the adrenal medulla by a factor of 3.5.

  7. Hemoglobin Labeled by Radioactive Lysine

    DOE R&D Accomplishments Database

    Bale, W. F.; Yuile, C. L.; DeLaVergne, L.; Miller, L. L.; Whipple, G. H.

    1949-12-08

    This paper reports on the utilization of tagged epsilon carbon of DL-lysine by a dog both anemic and hypoproteinemic due to repeated bleeding plus a diet low in protein. The experiment extended over period of 234 days, a time sufficient to indicate an erythrocyte life span of at least 115 days based upon the rate of replacement of labeled red cell proteins. The proteins of broken down red cells seem not to be used with any great preference for the synthesis of new hemoglobin.

  8. 16 CFR Appendix L to Part 305 - Sample Labels

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... FORMAT) ER19JY10.019 PROTOTYPE LABEL 7 LIGHTING FACTS LABEL FOR GENERAL SERVICE LAMPS CONTAINING MERCURY... MERCURY ER19JY10.021 SAMPLE LABEL 11 LIGHTING FACTS LABEL FOR GENERAL SERVICE LAMP CONTAINING MERCURY... MERCURY (TALL ORIENTATION) ER19JY10.023 SAMPLE LABEL 13 LIGHTING FACTS LABEL FOR GENERAL SERVICE...

  9. Final report-98-ERI-003 identification of population with lifetime 41Ca-labeled skeletons

    SciTech Connect

    Freeman, S P

    1999-02-25

    In 1997 we first postulated the existence of a special human population that had had their skeletons inadvertently isotopically adulterated in the past. We theorized that the population, and the necessary LLNL accelerator mass spectrometer (AMS) measurement technology, would prove a significant resource in the fight to combat osteoporosis. This LDRD project was to establish such. The project was significantly successful in its initial year, but was not renewed for another and the research is now ended at LLNL. We proposed a three-year program to (1) confirm the magnitude and extent of historical 41 Ca dosing, (2) exactly characterize the long-term 41 Ca signal by comparing it with conventional measurements of skeletal health, and (3) demonstrate the utility of the historically labeled population in evaluating an actual potential therapy for osteoporosis. However, rather than investigate historical records to learn the identity of those inadvertently dosed, find them, and if possible enroll them into a new protocol, this project was to be particularly efficient by making use of a multiyear archive of samples from original, inadvertent 41 Ca-dosing experiments at Creighton University in Omaha, Nebraska. Because the subjects had been dosed in conventional studies of calcium kinetics, much important correlating historical data would also be available for comparison. Measurements of contemporary urine samples specifically provided for this project by selected identified subjects would follow. We discovered a second archive at the University of Texas Southwestern Medical Center. This is potentially a better source of material as the samples were generated in numerous historical evaluations of actual osteoporosis therapies in which 41 Ca-impure radiotracers were used. The therapies might now powerfully be retrospectively evaluated, both to contribute to our understanding of the therapies and to highlight the potential of the use of 41 Ca tracer and LLNL measurement.

  10. Social determinants of diagnostic labels in depression.

    PubMed

    McPherson, Susan; Armstrong, David

    2006-01-01

    The role of diagnostic labels in medicine is usually that of labelling an illness as a means of communication. Control over labelling processes in medicine is ordinarily imposed via medical schools, textbooks, education or by diagnostic manuals. Diagnostic labels often change following new discoveries in underlying pathology such as 'consumption' being relabelled as 'TB' or 'cancer'. Sub-types of broad diagnostic labels also often emerge from such discoveries e.g. 'lung cancer' or 'throat cancer'. In mental health, underlying pathology is the subject of ongoing debate spanning ideas including the brain as a faulty organ, faulty genetics and environmental problems. With controversy over pathology comes controversy over labels and the idea that labels may be used not just for communication, but as devices of social and professional control, arising out of a social process. This study explores the codification of the diagnostic label 'depression' which emerged in the twentieth-century and has proliferated with numerous sub-types over the last 40 years. The aim is to examine its social determinants and context. Medline is used as a data source for professional label usage. A range of depression sub-type labels in professional use was identified. This exercise revealed many official and 'unofficial' terms in professional use. Citation rate plots by year were then generated for these depression sub-type labels. The rise and fall of different labels are examined in relation to social determinants and context, including publication of diagnostic manuals DSM and ICD, power shifts in psychiatry, the discovery of psychiatric drugs and the shift from inpatient to community care. Exploring the changing use of official and unofficial labels over time in this way provides a novel historical perspective on the concept of depression in the late twentieth-century.

  11. Chemical kin label in seabirds

    PubMed Central

    Célérier, Aurélie; Bon, Cécile; Malapert, Aurore; Palmas, Pauline; Bonadonna, Francesco

    2011-01-01

    Chemical signals yield critical socio-ecological information in many animals, such as species, identity, social status or sex, but have been poorly investigated in birds. Recent results showed that chemical signals are used to recognize their nest and partner by some petrel seabirds whose olfactory anatomy is well developed and which possess a life-history propitious to olfactory-mediated behaviours. Here, we investigate whether blue petrels (Halobaena caerulea) produce some chemical labels potentially involved in kin recognition and inbreeding avoidance. To overcome methodological constraints of chemical analysis and field behavioural experiments, we used an indirect behavioural approach, based on mice olfactory abilities in discriminating odours. We showed that mice (i) can detect odour differences between individual petrels, (ii) perceive a high odour similarity between a chick and its parents, and (iii) perceive this similarity only before fledging but not during the nestling developmental stage. Our results confirm the existence of an individual olfactory signature in blue petrels and show for the first time, to our knowledge, that birds may exhibit an olfactory kin label, which may have strong implications for inbreeding avoidance. PMID:21525047

  12. Label-free molecular imaging

    NASA Astrophysics Data System (ADS)

    Zhang, Junqi; Li, Qi; Fu, Rongxin; Wang, Tongzhou; Wang, Ruliang; Huang, Guoliang

    2014-03-01

    Optical microscopy technology has achieved great improvements in the 20th century. The detection limit has reached about twenty nanometers (with near-field optics, STED, PALM and STORM). But in the application areas such as life science, medical science, clinical treatment and especially in vivo dynamic measurement, mutual restrictions still exist between numeric aperture/magnification and working distance, fluorescent dependent, and between resolution and frame rate/field size, etc. This paper explores a hyperspectral scanning super-resolution label free molecules imaging method based on the white light interferometry. The vertical detection resolution was approximate to 1 nm which is the thickness of a single molecular layer and dynamic measuring range of thickness reaches to 10 μm. The spectrum-shifting algorithm is developed for robust restructure of images when the pixels are overlapped. Micro-biochip with protein binding and DNA amplification could be detected by using this spectral scanning super-resolution molecules imaging in label free. This method has several advantages as following: Firstly, the decoding and detecting steps are combined into one step. It makes tests faster and easier. Secondly, we used thickness-coded, minimized chips instead of a large microarray chip to carry the probes. This accelerates the interaction of the biomolecules. Thirdly, since only one kind of probes are attached to our thickness-coded, minimized chip, users can only pick out the probes they are interested in for a test without wasting unnecessary probes and chips.

  13. 16 CFR 309.17 - Labels.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... is centered. The band at the top of the label contains the name of the fuel. This band should measure 1″ (2.54 cm) deep. Spacing of the fuel name is 1/4″ (.64 cm) from the top of the label and 3/16.... “Helvetica black” type is used throughout. All type is centered. The band at the top of the label...

  14. Comparative Studies of Three Pairs of α- and γ-Conjugated Folic Acid Derivatives Labeled with Fluorine-18.

    PubMed

    Boss, Silvan D; Betzel, Thomas; Müller, Cristina; Fischer, Cindy R; Haller, Stephanie; Reber, Josefine; Groehn, Viola; Schibli, Roger; Ametamey, Simon M

    2016-01-20

    The folate receptor (FR) is upregulated in various epithelial cancer types (FR α-isoform), while healthy tissues show only restricted expression. FR-targeted imaging using folate radiopharmaceuticals is therefore a promising approach for the detection of FR-positive cancer tissue. Almost all folate-based radiopharmaceuticals have been prepared by conjugation at the γ-carboxylic functionality of the glutamate moiety of folic acid. In this work, three pairs of fluorinated α- and γ-conjugated folate derivatives were synthesized and their in vitro and in vivo properties compared. The syntheses of all six regioisomers were obtained in good chemical yields using a multistep synthetic approach including the highly selective Cu(I)-catalyzed 1,3-dipolar cycloaddition. The radiosyntheses of the α- and γ-conjugated (18)F-labeled folate derivatives were accomplished in moderate to good radiochemical yields, high radiochemical purities (>95%), and specific activities ranging from 25 to 196 GBq/μmol. In vitro, all folate derivatives showed high binding affinity to the FR-α (IC50 = 1.4-2.2 nM). In vivo PET imaging and biodistribution studies in FR-positive KB tumor-bearing mice demonstrated similar FR-specific tumor uptake for both regioisomers of each pair of compounds. However, FR-unspecific liver uptake was significantly lower for the α-regioisomers compared to the corresponding γ-regioisomers. In contrast, kidney uptake was up to 50% lower for the γ-regioisomers than for the α-regioisomers. These results show that the site of conjugation in the glutamyl moiety of folic acid has a significant impact on the in vivo behavior of (18)F-based radiofolates, but not on their in vitro FR-binding affinity. These findings may potentially stimulate new directions for the design of novel (18)F-labeled folate-based radiotracers.

  15. Fluorescent labeling and tracking of nanoclay.

    PubMed

    Diaz, Carlos A; Xia, Yining; Rubino, Maria; Auras, Rafael; Jayaraman, Krishnamurthy; Hotchkiss, Joseph

    2013-01-07

    We report a methodology developed to detect and track stable fluorescent-labeled nanoclay, in polymer-clay nanocomposite films, and in a contact solvent after migration testing. Fluorescein-5-maleimide (fluorescein) or tetramethylrhodamine-5-maleimide (rhodamine) was covalently bonded to organically modified montmorillonite (o-MMT). Fluorescein- and rhodamine-labeled nanoclay showed good thermal stability up to 220 °C and the rhodamine-labeled nanoclay remained stable at 250 °C. Confocal laser scanning microscopy was used to confirm the tagging and to detect the fluorescent-labeled nanoclays in various systems.

  16. Component Labeling Algorithm For Video Rate Processing

    NASA Astrophysics Data System (ADS)

    Gotoh, Toshiyuki; Ohta, Yoshiyuki; Yoshida, Masumi; Shirai, Yoshio

    1987-10-01

    In this paper, we propose a raster scanning algorithm for component labeling, which enables processing under pipeline architecture. In the raster scanning algorithm, labels are provisionally assigned to each pixel of components and, at the same time, the connectivities of labels are detected at first scan. Those labels are classified into groups based on the connectivities. Finally provisional labels are updated using the result of classification and a unique label is assigned to each pixel of components. However, in the conventional algorithm, the classification process needs a vast number of operations. This prevents realizing pipeline processing. We have developed a method of preprocessing to reduce the number of provisional labels, which limits the number of label connectivities. We have also developed a new classification method whose operation is proportionate to only the number of label connectivities itself. We have made experiments with computer simulation to verify this algorithm. The experimental results show that we can process 512 x 512 x 8 bit images at video rate(1/30 sec. per 1 image) when this algorithm is implemented on hardware.

  17. Optimal design of isotope labeling experiments.

    PubMed

    Yang, Hong; Mandy, Dominic E; Libourel, Igor G L

    2014-01-01

    Stable isotope labeling experiments (ILE) constitute a powerful methodology for estimating metabolic fluxes. An optimal label design for such an experiment is necessary to maximize the precision with which fluxes can be determined. But often, precision gained in the determination of one flux comes at the expense of the precision of other fluxes, and an appropriate label design therefore foremost depends on the question the investigator wants to address. One could liken ILE to shadows that metabolism casts on products. Optimal label design is the placement of the lamp; creating clear shadows for some parts of metabolism and obscuring others.An optimal isotope label design is influenced by: (1) the network structure; (2) the true flux values; (3) the available label measurements; and, (4) commercially available substrates. The first two aspects are dictated by nature and constrain any optimal design. The second two aspects are suitable design parameters. To create an optimal label design, an explicit optimization criterion needs to be formulated. This usually is a property of the flux covariance matrix, which can be augmented by weighting label substrate cost. An optimal design is found by using such a criterion as an objective function for an optimizer. This chapter uses a simple elementary metabolite units (EMU) representation of the TCA cycle to illustrate the process of experimental design of isotope labeled substrates.

  18. Organic labeling influences food valuation and choice.

    PubMed

    Linder, N S; Uhl, G; Fliessbach, K; Trautner, P; Elger, C E; Weber, B

    2010-10-15

    Everyday we choose between a variety of different food items trying to reach a decision that fits best our needs. These decisions are highly dependent on the context in which the alternatives are presented (e.g. labeling). We investigate the influence of cognition on food evaluation, using an fMRI experiment in which subjects saw and bid on different foods labeled with (or without) a widely known German emblem for organically produced food. Increased activity in the ventral striatum was found for foods labeled "organic" in comparison to conventionally labeled food. Between-subject differences in activity were related to actual everyday consumption behavior of organic food.

  19. Simultaneous Segmentation and Statistical Label Fusion.

    PubMed

    Asman, Andrew J; Landmana, Bennett A

    2012-02-23

    Labeling or segmentation of structures of interest in medical imaging plays an essential role in both clinical and scientific understanding. Two of the common techniques to obtain these labels are through either fully automated segmentation or through multi-atlas based segmentation and label fusion. Fully automated techniques often result in highly accurate segmentations but lack the robustness to be viable in many cases. On the other hand, label fusion techniques are often extremely robust, but lack the accuracy of automated algorithms for specific classes of problems. Herein, we propose to perform simultaneous automated segmentation and statistical label fusion through the reformulation of a generative model to include a linkage structure that explicitly estimates the complex global relationships between labels and intensities. These relationships are inferred from the atlas labels and intensities and applied to the target using a non-parametric approach. The novelty of this approach lies in the combination of previously exclusive techniques and attempts to combine the accuracy benefits of automated segmentation with the robustness of a multi-atlas based approach. The accuracy benefits of this simultaneous approach are assessed using a multi-label multi- atlas whole-brain segmentation experiment and the segmentation of the highly variable thyroid on computed tomography images. The results demonstrate that this technique has major benefits for certain types of problems and has the potential to provide a paradigm shift in which the lines between statistical label fusion and automated segmentation are dramatically blurred.

  20. Radiosynthesis and preliminary PET evaluation of (18)F-labeled 2-(1-(3-fluorophenyl)-2-oxo-5-(pyrimidin-2-yl)-1,2-dihydropyridin-3-yl)benzonitrile for imaging AMPA receptors.

    PubMed

    Yuan, Gengyang; Jones, Graham B; Vasdev, Neil; Liang, Steven H

    2016-10-01

    To prompt the development of (18)F-labeled positron emission tomography (PET) tracers for the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor, we have prepared (18)F-labeled 2-(1-(3-fluorophenyl)-2-oxo-5-(pyrimidin-2-yl)-1,2-dihydropyridin-3-yl)benzonitrile ([(18)F]8). The radiosynthesis was achieved by a one-pot two-step method that utilized a spirocyclic hypervalent iodine(III) mediated radiofluorination to prepare the (18)F-labeled 1-bromo-3-fluorobenzene ([(18)F]15) intermediate with K(18)F. A subsequent copper(I) iodide mediated coupling reaction was carried out with 2-(2-oxo-5-(pyrimidin-2-yl)-1,2-dihydropyridin-3-yl)benzonitrile (10) to [(18)F]8 in 10±2% uncorrected radiochemical yield relative to starting (18)F-fluoride with >99% radiochemical purity and 29.6±7.4Gbq/μmol specific activity at the time of injection. PET imaging studies with the title radiotracer in normal mice demonstrated good brain uptake (peak standardized uptake value (SUV)=2.3±0.1) and warrants further in vivo validation.

  1. Labeled nucleotide phosphate (NP) probes

    DOEpatents

    Korlach, Jonas; Webb, Watt W.; Levene, Michael; Turner, Stephen; Craighead, Harold G.; Foquet, Mathieu

    2009-02-03

    The present invention is directed to a method of sequencing a target nucleic acid molecule having a plurality of bases. In its principle, the temporal order of base additions during the polymerization reaction is measured on a molecule of nucleic acid, i.e. the activity of a nucleic acid polymerizing enzyme on the template nucleic acid molecule to be sequenced is followed in real time. The sequence is deduced by identifying which base is being incorporated into the growing complementary strand of the target nucleic acid by the catalytic activity of the nucleic acid polymerizing enzyme at each step in the sequence of base additions. A polymerase on the target nucleic acid molecule complex is provided in a position suitable to move along the target nucleic acid molecule and extend the oligonucleotide primer at an active site. A plurality of labelled types of nucleotide analogs are provided proximate to the active site, with each distinguishable type of nucleotide analog being complementary to a different nucleotide in the target nucleic acid sequence. The growing nucleic acid strand is extended by using the polymerase to add a nucleotide analog to the nucleic acid strand at the active site, where the nucleotide analog being added is complementary to the nucleotide of the target nucleic acid at the active site. The nucleotide analog added to the oligonucleotide primer as a result of the polymerizing step is identified. The steps of providing labelled nucleotide analogs, polymerizing the growing nucleic acid strand, and identifying the added nucleotide analog are repeated so that the nucleic acid strand is further extended and the sequence of the target nucleic acid is determined.

  2. F-18 labeled 3-fluorodiazepam

    SciTech Connect

    Luxen, A.; Barrio, J.R.; Bida, G.T.; Satyamurthy, N.; Phelps, M.E.

    1985-05-01

    3-Fluorodiazepam is a new and potent antianxiety agent with prolonged action. The authors found that molecular fluorine (0.5% in Ne) reacts cleanly with diazepam in freon or chloroform at room temperature to produce 3-fluorodiazepam in good yields. Successful syntheses have employed 2:1 to 5:1 molar ratios diazepam: fluorine to minimize the formation of byproducts. (/sup 18/F) 3-Fluorodiazepam, a potential candidate for PET studies, (specific activity 3-5 Ci/mmol) has been synthesized from /sup 18/F-F/sub 2/ using the same procedure, followed by column chromatographic purification (Silicagel, dichloromethane: ethyl acetate, 5:1) with a radiochemical yield of 12-20% (50% maximum) and a chemical and radiochemical purity >99% as judged by reversed-phase high pressure liquid chromatography analysis (Ultrasyl octyl column, 10 ..mu.. m, 4.6 x 250 mm i.d., 60% MeOH 40% water; flow rate, 1.0 ml/min; retention time for (/sup 18/F) fluorodiazepam, 11.4 min; for diazepam, 13.5 min; radioactivity and ultraviolet detectors). Lower radiochemical yields (5-7%), and significant formation of by-products were observed when (/sup 18/F)acetylhypofluorite, prepared in the gasphase, was used as the reagent. Readily accessible routes to /sup 18/F-labeled benzodiazepines of higher specific activity were also investigated. Approaches to the synthesis of high specific activity (>200 Ci/mmol) (/sup 18/F)3-fluorodiazepam involve nucleophilic displacement at carbon-3 (e.g. from 3-chlorodiazepam) with (/sup 18/F)fluoride ion. The results presented here demonstrate the synthetic accessibility of /sup 18/F-labeled benzodiazepines for application in neurotransmitter ligand studies with PET.

  3. Label Review Training: Module 2: Parts of the Label, Page 16

    EPA Pesticide Factsheets

    This module of the label review training describes the parts of the front and back panel of the pesticide label. You will learn what kinds of information each part includes, as well as how to organize these parts.

  4. Label Review Training: Module 2: Parts of the Label, Page 2

    EPA Pesticide Factsheets

    This module of the label review training describes the parts of the front and back panel of the pesticide label. You will learn what kinds of information each part includes, as well as how to organize these parts.

  5. Label Review Training: Module 2: Parts of the Label, Page 6

    EPA Pesticide Factsheets

    This module of the label review training describes the parts of the front and back panel of the pesticide label. You will learn what kinds of information each part includes, as well as how to organize these parts.

  6. Label Review Training: Module 2: Parts of the Label, Page 7

    EPA Pesticide Factsheets

    This module of the label review training describes the parts of the front and back panel of the pesticide label. You will learn what kinds of information each part includes, as well as how to organize these parts.

  7. Label Review Training: Module 2: Parts of the Label, Page 11

    EPA Pesticide Factsheets

    This module of the label review training describes the parts of the front and back panel of the pesticide label. You will learn what kinds of information each part includes, as well as how to organize these parts.

  8. Leukemic cell labeling with indium-111-oxine

    SciTech Connect

    Uchida, T.; Takagi, Y.; Matsuda, S.; Yui, T.; Ishibashi, T.; Kimura, H.; Kariyone, S.

    1984-01-01

    Leukemic cells were labeled with In-111-oxine in patients with acute leukemia. In vitro labeling studies revealed that labeling efficiency reached maximum 80.8 +- 3.6% (mean +- 1SD) by 2 times washes after 20 minutes incubation time. Cell viability was assessed by trypan blue exclusion test and in vitro culture of leukemic cells, which showed no cellular damage during labeling procedure. Elution of In-111 from the labeled cells was 10.0 +- 1.2% at 12 hours after labeling. For in vivo leukemic cell kinetic studies, more than 10/sup 8/ leukemic cells separated from Ficoll-Hypacque sedimentation were labeled by 30 minutes of In-111-oxine incubation and two times washes at 37/sup 0/C. In vivo studies were performed in 7 patients with acute myeloblastic, lymphoblastic leukemia and blastic crisis of chronic myelocytic leukemia. Labeled leukemic cells disappeared in single exponential fashion with half life of 9.6 to 31.8 hours. Total leukemic cell pool in peripheral circulation was calculated, which correlated well with peripheral leukemic cell counts (r=0.99). No relationship was observed between total leukemic cell pool and leukemic cell turnover rate. Migration patterns of labeled leukemic cells showed that pulmonary uptake was evident within 15 minutes after the infusion and returned to base-line. Splenic and hepatic uptake showed gradual increase up to 24 hours. Bone marrow accumulation was shown only in 2 cases. Presently, there are no suitable radionuclides for leukemic cell labeling. In-111-oxine labeled leukemic cells would overcome this difficulty.

  9. The reappropriation of stigmatizing labels: the reciprocal relationship between power and self-labeling.

    PubMed

    Galinsky, Adam D; Wang, Cynthia S; Whitson, Jennifer A; Anicich, Eric M; Hugenberg, Kurt; Bodenhausen, Galen V

    2013-10-01

    We present a theoretical model of reappropriation--taking possession of a slur previously used exclusively by dominant groups to reinforce another group's lesser status. Ten experiments tested this model and established a reciprocal relationship between power and self-labeling with a derogatory group term. We first investigated precursors to self-labeling: Group, but not individual, power increased participants' willingness to label themselves with a derogatory term for their group. We then examined the consequences of such self-labeling for both the self and observers. Self-labelers felt more powerful after self-labeling, and observers perceived them and their group as more powerful. Finally, these labels were evaluated less negatively after self-labeling, and this attenuation of stigma was mediated by perceived power. These effects occurred only for derogatory terms (e.g., queer, bitch), and not for descriptive (e.g., woman) or majority-group (e.g., straight) labels. These results suggest that self-labeling with a derogatory label can weaken the label's stigmatizing force.

  10. 21 CFR 1302.04 - Location and size of symbol on label and labeling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Location and size of symbol on label and labeling. 1302.04 Section 1302.04 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE LABELING AND PACKAGING REQUIREMENTS FOR CONTROLLED SUBSTANCES § 1302.04 Location and size of symbol on...

  11. 21 CFR 1302.04 - Location and size of symbol on label and labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 9 2013-04-01 2013-04-01 false Location and size of symbol on label and labeling. 1302.04 Section 1302.04 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE LABELING AND PACKAGING REQUIREMENTS FOR CONTROLLED SUBSTANCES § 1302.04 Location and size of symbol on...

  12. Portion Size Labeling and Intended Soft Drink Consumption: The Impact of Labeling Format and Size Portfolio

    ERIC Educational Resources Information Center

    Vermeer, Willemijn M.; Steenhuis, Ingrid H. M.; Leeuwis, Franca H.; Bos, Arjan E. R.; de Boer, Michiel; Seidell, Jacob C.

    2010-01-01

    Objective: To assess what portion size labeling "format" is most promising in helping consumers selecting appropriate soft drink sizes, and whether labeling impact depends on the size portfolio. Methods: An experimental study was conducted in fast-food restaurants in which 2 labeling formats (ie, reference portion size and small/medium/large…

  13. 21 CFR 1302.04 - Location and size of symbol on label and labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Location and size of symbol on label and labeling. 1302.04 Section 1302.04 Food and Drugs DRUG ENFORCEMENT ADMINISTRATION, DEPARTMENT OF JUSTICE LABELING AND PACKAGING REQUIREMENTS FOR CONTROLLED SUBSTANCES § 1302.04 Location and size of symbol on...

  14. Synthesis and in vivo Evaluation of Fluorine-18 and Iodine-123 Pyrazolo[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine Derivatives as PET and SPECT Radiotracers for Mapping A2A Receptors.

    PubMed

    Vala, Christine; Morley, Thomas J; Zhang, Xuechun; Papin, Caroline; Tavares, Adriana Alexandre S; Lee, H Sharon; Constantinescu, Cristian; Barret, Olivier; Carroll, Vincent M; Baldwin, Ronald M; Tamagnan, Gilles D; Alagille, David

    2016-09-06

    Imaging agents that target adenosine type 2A (A2A ) receptors play an important role in evaluating new pharmaceuticals targeting these receptors, such as those currently being developed for the treatment of movement disorders like Parkinson's disease. They are also useful for monitoring progression and treatment efficacy by providing a noninvasive tool to map changes in A2A receptor density and function in neurodegenerative diseases. We previously described the successful evaluation of two A2A -specific radiotracers in both nonhuman primates and in subsequent human clinical trials: [(123) I]MNI-420 and [(18) F]MNI-444. Herein we describe the development of both of these radiotracers by selection from a series of A2A ligands, based on the pyrazolo[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidine core of preladenant. Each of this series of 16 ligands was found to bind to recombinant human A2A receptor in the low nanomolar range, and of these 16, six were radiolabeled with either fluorine-18 or iodine-123 and evaluated in nonhuman primates. These initial in vivo results resulted in the identification of 7-(2-(4-(4-(2-[(18) F]fluoroethoxy)phenyl)piperazin-1-yl)ethyl)-2-(furan-2-yl)-7H-pyrazolo[4,3-e][1,2,4]triazolo[1,5-c]pyrimidin-5-amine ([(18) F]MNI-444) and 7-(2-(4-(2-fluoro-4-[(123) I]iodophenyl)piperazin-1-yl)ethyl)-2-(furan-2-yl)-7H-imidazo[1,2-c]pyrazolo[4,3-e]pyrimidin-5-amine ([(123) I]MNI-420) as PET and SPECT radiopharmaceuticals for mapping A2A receptors in brain.

  15. 7 CFR 60.300 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 3 2013-01-01 2013-01-01 false Labeling. 60.300 Section 60.300 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... FOR FISH AND SHELLFISH General Provisions Country of Origin Notification § 60.300 Labeling....

  16. 40 CFR 763.171 - Labeling requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... ACT ASBESTOS Prohibition of the Manufacture, Importation, Processing, and Distribution in Commerce of Certain Asbestos-Containing Products; Labeling Requirements § 763.171 Labeling requirements. (a) After August 27, 1990, manufacturers, importers, and processors of all asbestos-containing products that...

  17. 16 CFR 1615.5 - Labeling requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Labeling requirements. 1615.5 Section 1615.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY OF CHILDREN'S SLEEPWEAR: SIZES 0 THROUGH 6X (FF 3-71) The Standard § 1615.5 Labeling...

  18. 16 CFR 1616.6 - Labeling requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Labeling requirements. 1616.6 Section 1616.6 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE FLAMMABILITY OF CHILDREN'S SLEEPWEAR: SIZES 7 THROUGH 14 (FF 5-74) The Standard § 1616.6 Labeling...

  19. 78 FR 18272 - Energy Labeling Rule

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-26

    ... CFR Part 305 Energy Labeling Rule AGENCY: Federal Trade Commission (``FTC'' or ``Commission''). ACTION... in the SUPPLEMENTARY INFORMATION section below. Write ``Energy Label Ranges, Matter No. R611004'' on... Proposed Rulemaking (NPRM) until April 1, 2013. In the NPRM, the Commission proposed to amend the...

  20. 16 CFR 1630.5 - Labeling.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... FLAMMABILITY OF CARPETS AND RUGS (FF 1-70) The Standard § 1630.5 Labeling. If the carpet or rug has had a fire-retardant treatment or is made of fibers which have had a fire-retardant treatment, it shall be labeled...

  1. 16 CFR 1630.5 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... FLAMMABILITY OF CARPETS AND RUGS (FF 1-70) The Standard § 1630.5 Labeling. If the carpet or rug has had a fire-retardant treatment or is made of fibers which have had a fire-retardant treatment, it shall be labeled...

  2. 16 CFR 1630.5 - Labeling.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... FLAMMABILITY OF CARPETS AND RUGS (FF 1-70) The Standard § 1630.5 Labeling. If the carpet or rug has had a fire-retardant treatment or is made of fibers which have had a fire-retardant treatment, it shall be labeled...

  3. 47 CFR 15.19 - Labelling requirements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... identification described in § 2.1074 of this chapter and the following logo: (i) If the product is authorized... peripheral device, the text associated with the logo may be placed in a prominent location in the instruction...) and the logo must be displayed on the device. (4) The label shall not be a stick-on, paper label....

  4. 47 CFR 15.19 - Labelling requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... identification described in § 2.1074 of this chapter and the following logo: (i) If the product is authorized... peripheral device, the text associated with the logo may be placed in a prominent location in the instruction...) and the logo must be displayed on the device. (4) The label shall not be a stick-on, paper label....

  5. 49 CFR 583.5 - Label requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Label requirements. 583.5 Section 583.5 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AUTOMOBILE PARTS CONTENT LABELING § 583.5...

  6. 40 CFR 1033.135 - Labeling.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... permanently attached to the locomotive. (ii) The label must be lettered in the English language using a color... same engine part. (ii) The label must be lettered in the English language using a color that contrasts... to Tier 0+ line-haul locomotives.” (3) “This locomotive conforms to U.S. EPA regulations...

  7. 40 CFR 1033.135 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... permanently attached to the locomotive. (ii) The label must be lettered in the English language using a color... same engine part. (ii) The label must be lettered in the English language using a color that contrasts... to Tier 0+ line-haul locomotives.” (3) “This locomotive conforms to U.S. EPA regulations...

  8. 21 CFR 606.121 - Container label.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... optionally for differentiating ABO Blood groups: Blood group Color of label paper O Blue A Yellow B Pink AB... color scheme may be used for differentiating ABO Blood groups: Blood group Color of label O Blue A... CURRENT GOOD MANUFACTURING PRACTICE FOR BLOOD AND BLOOD COMPONENTS Finished Product Control §...

  9. 21 CFR 640.70 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... STANDARDS FOR HUMAN BLOOD AND BLOOD PRODUCTS Source Plasma § 640.70 Labeling. Link to an amendment published... information shall appear on the label affixed to each container of Source Plasma: (1) The proper name of the... shall follow the proper name in the same size and type of print as the proper name. If the Source...

  10. 27 CFR 20.134 - Labeling.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... exceeds 8-fluid ounces, the label shall also show the information required by paragraph (b) (1) or (2) of... the manufacturer, and the permit number or numbers of the place or places of manufacture. However, in... minimal identifying information (name, address and a phrase such as “distributed by”) on the label of...

  11. 10 CFR 20.1904 - Labeling containers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Labeling containers. 20.1904 Section 20.1904 Energy....1904 Labeling containers. (a) The licensee shall ensure that each container of licensed material bears... handling or using the containers, or working in the vicinity of the containers, to take precautions...

  12. 40 CFR 763.171 - Labeling requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... banned the distribution in U.S. commerce of this product under section 6 of the Toxic Substances Control... ACT ASBESTOS Prohibition of the Manufacture, Importation, Processing, and Distribution in Commerce of Certain Asbestos-Containing Products; Labeling Requirements § 763.171 Labeling requirements. (a)...

  13. Linguistic Labels: Conceptual Markers or Object Features?

    ERIC Educational Resources Information Center

    Sloutsky, Vladimir M.; Fisher, Anna V.

    2012-01-01

    Linguistic labels affect inductive generalization; however, the mechanism underlying these effects remains unclear. According to one similarity-based model, SINC (similarity, induction, naming, and categorization), early in development labels are features of objects contributing to the overall similarity of compared entities, with early induction…

  14. 40 CFR 600.301 - Labeling requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 31 2012-07-01 2012-07-01 false Labeling requirements. 600.301 Section 600.301 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Fuel Economy Labeling § 600.301...

  15. 40 CFR 600.301 - Labeling requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 30 2014-07-01 2014-07-01 false Labeling requirements. 600.301 Section 600.301 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) ENERGY POLICY FUEL ECONOMY AND GREENHOUSE GAS EXHAUST EMISSIONS OF MOTOR VEHICLES Fuel Economy Labeling § 600.301...

  16. 16 CFR 1631.5 - Labeling requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Labeling requirements. 1631.5 Section 1631.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF SMALL CARPETS AND RUGS (FF 2-70) The Standard § 1631.5 Labeling requirements....

  17. 16 CFR 1630.5 - Labeling.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Labeling. 1630.5 Section 1630.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF CARPETS AND RUGS (FF 1-70) The Standard § 1630.5 Labeling. If the carpet or rug has had a...

  18. 16 CFR 1631.5 - Labeling requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Labeling requirements. 1631.5 Section 1631.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF SMALL CARPETS AND RUGS (FF 2-70) The Standard § 1631.5 Labeling requirements....

  19. 16 CFR 1630.5 - Labeling.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Labeling. 1630.5 Section 1630.5 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FLAMMABLE FABRICS ACT REGULATIONS STANDARD FOR THE SURFACE FLAMMABILITY OF CARPETS AND RUGS (FF 1-70) The Standard § 1630.5 Labeling. If the carpet or rug has had a...

  20. 40 CFR 205.158 - Labeling requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... section with the statement; “For Export Only”. (c) Any competition motorcycle as defined in § 205.151(a)(3... TRANSPORTATION EQUIPMENT NOISE EMISSION CONTROLS Motorcycles § 205.158 Labeling requirements. (a)(1) The manufacturer of any vehicle subject to this subpart must, at the time of manufacture, affix a label, of...

  1. 16 CFR 1209.9 - Labeling requirement.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SAFETY STANDARD FOR CELLULOSE INSULATION The Standard § 1209.9 Labeling requirement. (a) Manufacturers, importers, and private labelers of cellulose insulation shall place on all containers of cellulose... corrosiveness of cellulose insulation. To meet this requirement manufacturers, importers, and private...

  2. 16 CFR 1209.9 - Labeling requirement.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SAFETY STANDARD FOR CELLULOSE INSULATION The Standard § 1209.9 Labeling requirement. (a) Manufacturers, importers, and private labelers of cellulose insulation shall place on all containers of cellulose... corrosiveness of cellulose insulation. To meet this requirement manufacturers, importers, and private...

  3. 16 CFR 1209.9 - Labeling requirement.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SAFETY STANDARD FOR CELLULOSE INSULATION The Standard § 1209.9 Labeling requirement. (a) Manufacturers, importers, and private labelers of cellulose insulation shall place on all containers of cellulose... corrosiveness of cellulose insulation. To meet this requirement manufacturers, importers, and private...

  4. 16 CFR 1209.9 - Labeling requirement.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... SAFETY STANDARD FOR CELLULOSE INSULATION The Standard § 1209.9 Labeling requirement. (a) Manufacturers, importers, and private labelers of cellulose insulation shall place on all containers of cellulose... corrosiveness of cellulose insulation. To meet this requirement manufacturers, importers, and private...

  5. 16 CFR 309.17 - Labels.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ALTERNATIVE FUELS AND ALTERNATIVE FUELED VEHICLES Requirements for Alternative Fuels Label Specifications... alternative vehicle fuel (other than electricity) labels with disclosure of principal component only. The... the reasons that you want to use it. (2) Non-liquid alternative vehicle fuel (other than...

  6. 16 CFR 309.17 - Labels.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ALTERNATIVE FUELS AND ALTERNATIVE FUELED VEHICLES Requirements for Alternative Fuels Label Specifications... alternative vehicle fuel (other than electricity) labels with disclosure of principal component only. The... the reasons that you want to use it. (2) Non-liquid alternative vehicle fuel (other than...

  7. 16 CFR 309.17 - Labels.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... ALTERNATIVE FUELS AND ALTERNATIVE FUELED VEHICLES Requirements for Alternative Fuels Label Specifications... alternative vehicle fuel (other than electricity) labels with disclosure of principal component only. The... the reasons that you want to use it. (2) Non-liquid alternative vehicle fuel (other than...

  8. 16 CFR 309.17 - Labels.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... ALTERNATIVE FUELS AND ALTERNATIVE FUELED VEHICLES Requirements for Alternative Fuels Label Specifications... alternative vehicle fuel (other than electricity) labels with disclosure of principal component only. The... the reasons that you want to use it. (2) Non-liquid alternative vehicle fuel (other than...

  9. 24 CFR 3280.11 - Certification label.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... approximately 2 in. by 4 in. in size and shall be permanently attached to the manufactured home by means of 4... URBAN DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS General § 3280.11 Certification label. (a) A permanent label shall be affixed to each transportable section of each manufactured...

  10. Luminogenic "clickable" lanthanide complexes for protein labeling.

    PubMed

    Candelon, Nicolas; Hădade, Niculina D; Matache, Mihaela; Canet, Jean-Louis; Cisnetti, Federico; Funeriu, Daniel P; Nauton, Lionel; Gautier, Arnaud

    2013-10-14

    Development of lanthanide-based luminescent "switch-on" systems via azide-alkyne [3+2] cycloaddition is described. We used these for non-specific protein labeling and as tags for specific and selective activity-based protein labeling.

  11. Reversibility of cell surface label rearrangement

    PubMed Central

    1976-01-01

    Cell surface labeling can cause rearrangements of randomly distributed membrane components. Removal of the label bound to the cell surface allows the membrane components to return to their original random distribution, demonstrating that label is necessary to maintain as well as to induce rearrangements. With scanning electron microscopy, the rearrangement of concanavalin A (con A) and ricin binding sites on LA-9 cells has been followed by means of hemocyanin, a visual label. The removal of con A from its binding sites at the cell surface with alpha- methyl mannoside, and the return of these sites to their original distribution are also followed in this manner. There are labeling differences with con A and ricin. Under some conditions, however, the same rearrangements are seen with both lectins. The disappearance of labeled sites from areas of ruffling activity is a major feature of the rearrangements seen. Both this ruffling activity and the rearrangement of label are sensitive to cytochalasin B, and ruffling activity, perhaps along with other cytochalasin-sensitive structure, may play a role in the rearrangements of labeled sites. PMID:1025154

  12. The anatomy of a laser label

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Laser labeling of fruits and vegetables is an efficient alternative to adhesive tags. The advantages of this system are numerous. In general the label consists of alphanumerical characters formed by laser generated pinhole depressions that penetrate the produce’s surface creating visible markings. H...

  13. 40 CFR 205.169 - Labeling requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... systems or exhaust system components to be distributed in commerce. (b) The labels or marks shall be... readily visible position when the exhaust system or exhaust system component is installed on all... language in block letters and numerals in a color that contrasts with its background. (e) The label or...

  14. Labels and Children's Perception of Faces.

    ERIC Educational Resources Information Center

    Katz, Phyllis A.; Seavey, Carol

    The relation between type of label and perception of faces was assessed. Sixty-four second and sixth grade Ss were randomly assigned to four experimental conditions in which various kinds of labeling training were associated with four purple and green smiling and frowning faces. Ss then judged the similarity of pairs of the faces. Results revealed…

  15. 27 CFR 18.55 - Label.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Label. 18.55 Section 18.55 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS PRODUCTION OF VOLATILE FRUIT-FLAVOR CONCENTRATE Operations § 18.55 Label. Each...

  16. 27 CFR 18.55 - Label.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Label. 18.55 Section 18.55 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS PRODUCTION OF VOLATILE FRUIT-FLAVOR CONCENTRATE Operations § 18.55 Label. Each...

  17. 16 CFR 306.12 - Labels.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... number on octane labels, which is in Franklin gothic type. All type is centered. Spacing of the label is... Helvetica series or equivalent type is used for all numbers and letters with the exception of the octane... set in 10 point Helvetica Bold, all capitals, with letterspace set at 101/2 points. The octane...

  18. 16 CFR 306.12 - Labels.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... number on octane labels, which is in Franklin gothic type. All type is centered. Spacing of the label is... Helvetica series or equivalent type is used for all numbers and letters with the exception of the octane... set in 10 point Helvetica Bold, all capitals, with letterspace set at 101/2 points. The octane...

  19. 16 CFR 306.12 - Labels.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... number on octane labels, which is in Franklin gothic type. All type is centered. Spacing of the label is... Helvetica series or equivalent type is used for all numbers and letters with the exception of the octane... set in 10 point Helvetica Bold, all capitals, with letterspace set at 101/2 points. The octane...

  20. 21 CFR 701.11 - Identity labeling.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC LABELING Package Form § 701.11 Identity labeling. (a) The principal display panel of a cosmetic in...) Such statement of identity shall be in terms of: (1) The common or usual name of the cosmetic; or...