Search

Your search keyword '"Aigbirhio, F. I."' showing total 44 results
Start Over Author "Aigbirhio, F. I."
44 results on '"Aigbirhio, F. I."'

6. Abstracts of the 24th international isotope society (UK group) symposium: synthesis and applications of labelled compounds 2015

Author

Aigbirhio, F. I., primary, Allwein, S., additional, Anwar, A., additional, Atzrodt, J., additional, Audisio, D., additional, Badman, G, additional, Bakale, R., additional, Berthon, F., additional, Bragg, R., additional, Brindle, K. M., additional, Bushby, N., additional, Campos, S., additional, Cant, A. A., additional, Chan, M. Y. T., additional, Colbon, P., additional, Cornelissen, B., additional, Czarny, B., additional, Derdau, V., additional, Dive, V., additional, Dunscombe, M., additional, Eggleston, I., additional, Ellis-Sawyer, K., additional, Elmore, C. S., additional, Engstrom, P., additional, Ericsson, C., additional, Fairlamb, I. J. S., additional, Georgin, D., additional, Godfrey, S. P., additional, He, L., additional, Hickey, M. J., additional, Huscroft, I. T., additional, Kerr, W. J., additional, Lashford, A., additional, Lenz, E., additional, Lewinton, S., additional, L'Hermite, M. M., additional, Lindelöf, Å., additional, Little, G., additional, Lockley, W. J. S., additional, Loreau, O., additional, Maddocks, S., additional, Marguerit, M., additional, Mirabello, V., additional, Mudd, R. J., additional, Nilsson, G. N., additional, Owens, P. K., additional, Pascu, S.I., additional, Patriarche, G., additional, Pimlott, S. L., additional, Pinault, M., additional, Plastow, G., additional, Racys, D. T., additional, Reif, J., additional, Rossi, J., additional, Ruan, J., additional, Sarpaki, S., additional, Sephton, S. M., additional, Simonsson, R., additional, Speed, D. J., additional, Sumal, K., additional, Sutherland, A., additional, Taran, F., additional, Thuleau, A., additional, Wang, Y., additional, Waring, M., additional, Watters, W. H., additional, Wu, J, additional, and Xiao, J., additional

Published
2016
Full Text
View/download PDF

7. Dissociable Rate-Dependent Effects of Oral Methylphenidate on Impulsivity and D2/3 Receptor Availability in the Striatum

Author

Caprioli, D., primary, Jupp, B., additional, Hong, Y. T., additional, Sawiak, S. J., additional, Ferrari, V., additional, Wharton, L., additional, Williamson, D. J., additional, McNabb, C., additional, Berry, D., additional, Aigbirhio, F. I., additional, Robbins, T. W., additional, Fryer, T. D., additional, and Dalley, J. W., additional

Published
2015
Full Text
View/download PDF

9. 15th International Isotope Society (UK group) Symposium

Author

Aigbirhio, F. I., primary, Alexakis, E., additional, Allen, J., additional, Baron, J.‐C., additional, Beech, J., additional, Beyer, J., additional, Bloxsidge, J. P., additional, Botting, N. P., additional, Brichard, L., additional, Bushby, N., additional, Cable, K., additional, Clark, J. C., additional, Conway, L. K., additional, Del Fiore, G., additional, Dollé, F., additional, Ellames, G., additional, Feling, N., additional, Fryatt, T., additional, Fryer, T. D., additional, Gee, A. D., additional, Haajanen, K., additional, Harding, J. R., additional, Haswell, S. J., additional, Hickey, M. J., additional, Holt, D. W., additional, Hooper, J., additional, Johnston, A., additional, Johnston, G., additional, Jones, J. R., additional, Kent, B., additional, Kingston, L. P., additional, Kitson, S. L., additional, Knagg, E., additional, Koch, B., additional, Kuhnert, N., additional, Lang, M., additional, Lang‐Fugmann, S., additional, Lawrie, K. W. M., additional, Lemaire, C., additional, Lewis, R. J., additional, Lockley, W. J. S., additional, Luxen, A., additional, Manning, C. O., additional, Mather, A. N., additional, Meath, P., additional, Passchier, J., additional, Perrie, J. A., additional, Plenevaux, A., additional, Plisson, C., additional, Probst, K. C., additional, Rees, D. O., additional, Rivron, L., additional, Rustidge, D., additional, Rüth, M., additional, Schofield, J. M., additional, Scott, P., additional, Sontag, B., additional, Spiteller, P., additional, Stachulski, A. V., additional, Steglich, W., additional, Wadsworth, A. H., additional, Watts, P., additional, Warburton, L., additional, Weissberg, P., additional, Wiles, C., additional, Wilkinson, D. J., additional, Willis, C. L., additional, and Aigbirhio, F. I., additional

Published
2006
Full Text
View/download PDF

10. Abstracts of the 22nd International Isotope Society (UK Group) Symposium: synthesis and applications of labelled compounds 2013

Author

Aboagye, E. O., primary, Aigbirhio, F. I., additional, Allen, P., additional, Arent, R., additional, Arrowsmith, R. L., additional, Banci, G., additional, Bagley, M. C., additional, Bailey, C. D., additional, Blake, T., additional, Bunt, A. J., additional, Bushby, N., additional, Carroll, L., additional, Cons, B. D., additional, Cortezon, F., additional, Dilworth, J. R., additional, Dorff, P. N., additional, Eggleston, I. M., additional, Ellames, G., additional, Elmore, C. S., additional, Ernst, G., additional, Estrela, P., additional, Faithfull, J., additional, Ge, H., additional, Geach, N. J., additional, Hall, J., additional, Harding, J., additional, Harwood, L. M., additional, Hickey, M. J., additional, Heys, J. R., additional, Hogg, C., additional, Hudson, M. J., additional, James, T., additional, Kerr, W. J., additional, Killick, D., additional, Kingston, L. P., additional, Kociok-Köhn, G., additional, Landvatter, S., additional, Lewis, F., additional, Lockley, W. J. S., additional, Marken, F., additional, Mudd, R. J., additional, Pascu, S. I., additional, Pheko, T., additional, Powell, M. E., additional, Reid, M, additional, Riss, P. J., additional, Ruhl, T., additional, Rustidge, D. C., additional, Schenk, D. J., additional, Schofield, C., additional, Schweiger, L., additional, Sharma, P., additional, Smith, D., additional, Tuttle, C. T. T., additional, Testa, A., additional, Tyson, J. A., additional, Tyrrell, R. M., additional, Urbanek, R., additional, Wilkinson, D. J., additional, Willis, C. L., additional, and Zanda, M., additional

Published
2014
Full Text
View/download PDF

14. Abstracts of the 18th international isotope society (UK group) symposium: synthesis & applications of labelled compounds 2009

Author

Aigbirhio, F. I., primary, Allen, J., additional, Arrowsmith, R. L., additional, Athlan, A., additional, Badman, G. T., additional, Bayly, S. R., additional, Bedford, R., additional, Botting, N. P., additional, Bragg, R. A., additional, Brasseur, D., additional, Bushby, N., additional, Cable, K. M., additional, Chan, F., additional, Christlieb, M., additional, Churchill, G. C., additional, Collison, D., additional, Denoux, M., additional, Dilworth, J. R., additional, Farrar, G., additional, Gotfredsen, C. H., additional, Greaney, M. F., additional, Harding, J. R., additional, Harris, P., additional, Harwood, S. J., additional, Heglund, I. F., additional, Hendry, D., additional, Hosseini, M., additional, Johnston, J. S., additional, Jones, S., additional, Jordan, A., additional, Killick, D. A., additional, Kitson, S. L., additional, Kowalczyk, R. M., additional, Lawrie, K. W. M., additional, Lockley, W. J. S., additional, Madge, D., additional, Manning, C., additional, Marshall, L. J., additional, McNeill, A. H., additional, Newman, J. J., additional, Pascu, S. I., additional, Roy, S., additional, Schofield, J., additional, Shanmugham, M. S., additional, Shipley, N. J., additional, Simmonds, A. J., additional, Smith, D., additional, Smith, S. L., additional, Steward, O. R., additional, Tanner, D., additional, Travers, J. G., additional, Tyrrell, R. M., additional, Vital, P., additional, Waghorn, P. A., additional, Warrington, B., additional, Watters, W., additional, Willcocks, K., additional, Williams, G. D., additional, Young, C. G., additional, and Zhong, J., additional

Published
2010
Full Text
View/download PDF

15. Abstracts of the 17th International Isotope Society (UK group) Symposium Synthesis and Applications of Labelled Compounds 2008

Author

Aigbirhio, F. I., primary, Allen, P., additional, Andersson, S., additional, Anton, M., additional, Barron, D., additional, Bloom, A. J., additional, Botting, N. P., additional, Brandau, W., additional, Brichard, L., additional, Brown, J. A., additional, Brown, R. T., additional, Cable, K. M., additional, Caffrey, M., additional, Carroll, M. A., additional, Chaplin, D. J., additional, Coissard, V., additional, Cuyckens, F., additional, Demmer, O., additional, Dijkgraaf, I., additional, Dyke, A. M., additional, Gill, D. M., additional, Hall, K. A., additional, Hester, A. J., additional, Hickey, M., additional, Irvine, S., additional, Janssen, C., additional, Kerr, W. J., additional, Kessler, H., additional, Kingston, L. P., additional, Landreau, C., additional, Lawrie, K. W. M., additional, Lloyd‐Jones, G., additional, Loaring, H., additional, Lockley, W. J. S., additional, Marshall, L. J., additional, Mo, B., additional, Moseley, J. D., additional, Murrell, V. L., additional, Nilsson, G. N., additional, Oekonomopulos, R., additional, Pinney, K. G., additional, Pleasance, S., additional, Raddatz, S., additional, Rees, A. T., additional, Reid, R. G., additional, Renny, J. S., additional, Robert, F., additional, Rustidge, D., additional, Schumacher, U., additional, Schwaiger, D. M., additional, Sharma, S., additional, Soloviev, D., additional, Spivey, A. C., additional, Sriram, M., additional, Thijssen, J., additional, Tseng, C.‐C., additional, Verluyten, W., additional, Viton, F., additional, Vliegen, M., additional, Weldon, H., additional, Wester, H‐J., additional, Wilkinson, D. J., additional, Williams, J. M. J., additional, Williamson, G., additional, Willis, C. L., additional, and Yan, R., additional

Published
2009
Full Text
View/download PDF

17. 16th International Isotope Society (UK group) Symposium

Author

Åberg, G., primary, Aigbirhio, F. I., additional, Alexakis, E., additional, Al-Maharik, N., additional, Almi, M., additional, Ambacher, Y., additional, Andersson, S., additional, Athlan, A., additional, Badman, G., additional, Baldwin, S. A., additional, Baumann, M., additional, Baxendale, I. R., additional, Botting, N. P., additional, Bragg, R. A., additional, Brown, J. A., additional, Burton, A., additional, Bushby, N., additional, Cable, K., additional, Campbell, G., additional, Carr, R., additional, Carroll, M., additional, Chen, L., additional, Christlieb, M., additional, Davies, P., additional, Ellames, G. J., additional, Ellis, W., additional, Elmore, C., additional, Fryatt, T., additional, Geach, N., additional, Harding, J. R., additional, Hartmann, S., additional, Harwood, S., additional, Hayward, J. J., additional, Henderson, P. J. F., additional, Herbert, R. B., additional, Heys, J. R., additional, Hölzl, S., additional, Hopkin, M. D., additional, Horn, P., additional, Ilyas, T., additional, Irvine, S., additional, Jackson, S. D., additional, Jin, J., additional, Keats, A., additional, Kennedy, A. R., additional, Kerr, W. J., additional, Kitching, M. O., additional, Landreau, C., additional, Lanners, S., additional, Lawrence, R., additional, Lawrie, K. W. M., additional, Ley, S. V., additional, Little, G., additional, Lockley, W. J. S., additional, Maier, D., additional, Manning, C., additional, McNeill, A., additional, Middleton, D. A., additional, Montgomery, S., additional, Morrison, J. J., additional, Mrzljak, L., additional, Newman, J., additional, Newsome, J., additional, Nikbin-Roudsari, N., additional, Nilsson, G. N., additional, Oldfield, M. F., additional, Patching, S. G., additional, Procter, D. J., additional, Randall, G., additional, Robertson, A. A., additional, Rummel, C. S., additional, Rustidge, D., additional, Sherhod, R., additional, Shipley, N., additional, Smith, C. D., additional, Smith, C. J., additional, Smith, D. I., additional, Song, C., additional, Tamborini, L., additional, Waterhouse, I., additional, Watts, A., additional, Werkheiser, J. L., additional, Williams, G., additional, Willis, C. L., additional, Woodward, P., additional, Yan, R., additional, Young, G., additional, and Zhang, Q., additional

Published
2008
Full Text
View/download PDF

19. How affected is oxygen metabolism in DWI lesions?

Author

Guadagno, J. V., primary, Warburton, E. A., additional, Jones, P. S., additional, Day, D. J., additional, Aigbirhio, F. I., additional, Fryer, T. D., additional, Harding, S., additional, Price, C. J., additional, Green, H. A., additional, Barret, O., additional, Gillard, J. H., additional, and Baron, J. -C., additional

Published
2006
Full Text
View/download PDF

20. Coexisting low cerebral blood flow and volume in head injury is due to microvascular ischaemia, not hypometabolism

Author

Coles, J. P., primary, Menon, D. K., additional, Fryer, T. D., additional, Chatfield, D. A., additional, Gupta, A. K., additional, Steiner, L. A., additional, Johnston, A. J., additional, Nortje, J., additional, Hutchinson, P. J.A., additional, Aigbirhio, F. I., additional, Clark, J. C., additional, and Pickard, J. D., additional

Published
2005
Full Text
View/download PDF

22. GE PETtrace and associated systems, 4 years experience in Cambridge.

Author

Clark, J. C., Aigbirhio, F. I., Burke, P., and Downey, S. P. M. J.

Subjects
*CYCLOTRONS, *POSITRON emission tomography
Abstract

In 1994 The University of Cambridge selected a General Electric (GE) PETtrace cyclotron for installation at it's Clinical School site at Addenbrooke's as part of a Positron Emission Tomography (PET) Neuroimaging package. The cyclotron was installed in a vault with labyrinth access. There is an associated Radiopharmaceutical laboratory with 3 hot cells. Equipment was delivered by GE for the production of [[sup 18]F]FDG, [[sup 11]C] Iodomethane and [sup 11]C/[sup 15]O gas processing. We report our experience with the cyclotron and associated equipment with reference to: 1. Cyclotron vault radiation shielding performance. 2. Post irradiation dose rates in the Cyclotron vault 3.Cyclotron and subsystems performance, problems and solutions. 4.Radiosynthetic equipment performance problems and solutions. 5.The Clinical Research program at The Wolfson Brain Imaging Center. [ABSTRACT FROM AUTHOR]

Published
2001

24. PERILESIONAL 18F-DEOXYGLUCOSE UPTAKE FOLLOWING HEAD INJURY: PET FINDINGS IN PATIENTS RECIEVING IV ANESTHETIC AGENTS.

Author

Menon, D. K., primary, Minhas, P. S., additional, Matthews, J. C., additional, Downey, S. P.M.J., additional, Kendall, I. V., additional, Visvikis, D., additional, Williams, E. J., additional, Parry, D., additional, Turkheimer, F. E., additional, Herrod, N. J., additional, Kemp, P., additional, Aigbirhio, F. I., additional, Carpenter, T. A., additional, Clark, J. C., additional, and Pickard, J. D., additional

Published
1998
Full Text
View/download PDF

25. PERILESIONAL18 F-DEOXYGLUCOSE UPTAKE FOLLOWING HEAD INJURY

Author

Menon, D. K., primary, Minhas, P. S., additional, Matthews, J. C., additional, Downey, S. P. M. J., additional, Kendall, I.V., additional, Visvikis, D., additional, Williams, E. J., additional, Parry, D., additional, Turkheimer, F. E., additional, Herrod, N. J., additional, Kemp, P., additional, Aigbirhio, F. I., additional, Carpenter, T. A., additional, Clark, J. C., additional, and Pickard, J. D., additional

Published
1998
Full Text
View/download PDF

27. Radiosynthesis of 11-[18F]fluoroundecyltriphenylphosphonium (MitoF) as a potential mitochondria-specific positron emission tomography radiotracer.

Author

Li, L., Brichard, L., Larsen, L., Menon, D. K., Smith, R. A. J., Murphy, M. P., and Aigbirhio, F. I.

Subjects
MITOCHONDRIAL membranes, TRIPHENYLPHOSPHINE, MEMBRANE potential, POSITRON emission tomography, RADIOACTIVE tracers, RADIOCHEMISTRY
Abstract

Changes in the magnitude of the mitochondrial membrane potential occur in a range of important pathologies. To assess changes in membrane potential in patients, we set out to develop an improved mitochondria-targeted positron emission tomography probe comprising a lipophilic triphenylphosphonium cation attached to a fluorine-18 radionuclide via an 11-carbon alkyl chain, which is well-established to effectively transport to and localise within mitochondria. Here, we describe the radiosynthesis of this probe, 11-[18F]fluoroundecyl-triphenylphosphonium (MitoF), from no-carrier-added [18F]fluoride and a fully automated synthetic protocol to prepare it in good radiochemical yields (2-3 GBq at end-of-synthesis) and radiochemical purity (97-99%). Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Published
2013
Full Text
View/download PDF

29. Disposition of inhaled 1,1,1,2-tetrafluoroethane (HFA134A) in healthy subjects and in patients with chronic airflow limitation. Measurement by 18F-labeling and whole-body gamma-counting.

Author

Pike, V W, Aigbirhio, F I, Freemantle, C A, Page, B C, Rhodes, C G, Waters, S L, Jones, T, Olsson, P, Ventresca, G P, and Tanner, R J

Abstract

HFA134a (1,1,1,2-tetrafluoroethane) is a nonozone-depleting candidate to replace the chlorofluorocarbons used as propellants in metered-dose inhalers (MDIs) for pharmaceuticals that are widely used in the treatment of respiratory tract disease. As a means for ensuring the safety of such a compound for human use, it is necessary to establish that there is no excessive or unexpected accumulation in the body and in selected regions. A sensitive whole-body gamma-counting technique has been used with 18F-labeled HFA134a to measure the whole-body and regional absorption, distribution, and retention of HFA134a after administration in humans by single-breath inhalation. In seven healthy subjects, labeled HFA134a was rapidly eliminated by ventilation during the first few minutes, with an average of 9.6% of the radioactivity retained in the body at 5 min. This radioactivity cleared with an apparent terminal half-life of 1.5-4.2 hr to leave, on average, < 1% of the administered dose (< 750 micrograms, approximately 0.2 microCi) retained in the body at 5.8 hr. Disposition of radioactivity was independent of the position of label. Thus, there was no evidence of any significant degradative metabolism. On average, only 0.0056% of the administered dose appeared in the urine within the first 2 hr. Later samples contained no significant radioactivity. Inhaled HFA134a first distributed to all regions of the body and then cleared without evident accumulation in any specific region.(ABSTRACT TRUNCATED AT 250 WORDS)

Published
1995
Full Text
View/download PDF

30. Ring-Methyl Activation in Pentamethylcyclopentadienyl Complexes. 5.<SUP>1</SUP> Syntheses and Structures of Tetramethylfulvene Complexes of Ruthenium(II)

Author

Fan, L., Wei, C., Aigbirhio, F. I., Turner, M. L., Gusev, O. V., Morozova, L. N., Knowles, D. R. T., and Maitlis, P. M.

Abstract

As previously reported, [{(η5-C5Me5)RuCl2}2], 1a, is oxygenated to the μ-oxo complex, [{(η5-C5Me5)RuCl2}2O], 2a (Angelici, R. J.; et al Organometallics 1992, 11, 2303). It is now shown that 2a spontaneously decomposes in chloroform solution by activation of a methyl C−H bond, to give the dinuclear tetramethylfulvene (TMF) complex [{(η6-C5Me4CH2)RuCl2}2], 3a, and water. The structure of 3a in the solid state (established by an X-ray structure determination) showed two crystallographically different but structurally similar centrosymmetric dinuclear molecules, each having a TMF η6-bonded to ruthenium(II). Each metal atom is approximately octahedrally coordinated by the η6-C5Me4CH2 and by three chlorides, two of which bridge to the other ruthenium and one of which is terminal. The chloride bridges are broken on reaction with ligands L to give [(η6-C5Me4CH2)RuCl2(L)], 4a (L = py), or 5a (L = Me2SO). All the complexes 2−5 are diamagnetic. NMR spectra of solutions of 3a show the presence of several structural isomers; these do not interconvert rapidly on the NMR time scale below 70 °C. The adducts 4a and 5a also show an unexpected rigidity; thus, 4a shows two noninterconverting isomers (rotamers). One is symmetric (trans), and the other unsymmetric (cis). The bonding is interpreted in terms of a η4,η2-TMF to Ru(II) rather than the alternative η5,η1-TMF to Ru(IV), by analysis of the details of the crystal structure determination of 3a and the 1J(C−H) of the exocyclic &dbd;CH2 in the 13C NMR spectrum. Reasons for the observed geometries are proposed. The mechanism for the O2-induced C−H activation is discussed.

Published
1996

41. Imaging regional variation of cellular proliferation in gliomas using 3'-deoxy-3'-[18F]fluorothymidine positron-emission tomography: an image-guided biopsy study.

Author

Price SJ, Fryer TD, Cleij MC, Dean AF, Joseph J, Salvador R, Wang DD, Hutchinson PJ, Clark JC, Burnet NG, Pickard JD, Aigbirhio FI, and Gillard JH

Subjects
Adolescent, Adult, Aged, Biopsy methods, Brain Mapping methods, Brain Neoplasms pathology, Cell Proliferation, Female, Glioma pathology, Humans, Magnetic Resonance Imaging methods, Male, Middle Aged, Radiology, Interventional methods, Sensitivity and Specificity, Young Adult, Brain Neoplasms diagnostic imaging, Dideoxynucleosides, Glioma diagnostic imaging, Positron-Emission Tomography methods, Radiopharmaceuticals
Abstract

Aim: To compare regional variations in uptake of 3'-deoxy-3'- [(18)F]-fluorothymidine (FLT) images using positron-emission tomography (PET) with measures of cellular proliferation from biopsy specimens obtained by image-guided brain biopsies., Materials and Methods: Fourteen patients with a supratentorial glioma that required an image-guided brain biopsy were imaged preoperatively with dynamic PET after the administration of FLT. Maps of FLT irreversible uptake rate (K(i)) and standardized uptake value (SUV) were calculated. These maps were co-registered to a gadolinium-enhanced T1-weighted spoiled gradient echo (SPGR) sequence that was used for biopsy guidance, and the mean and maximum K(i) and SUV determined for each biopsy site. These values were correlated with the MIB-1 labelling index (a tissue marker of proliferation) from these biopsy sites., Results: A total of 57 biopsy sites were studied. Although all measures correlated with MIB-1 labelling index, K(i)(max) provided the best correlation (Pearson coefficient, r=0.68; p<0.001). In low-grade gliomas the K(i)(mean) (+/-SD) was significantly higher than in normal tissue (3.3+/-1.7x10(-3)ml(plasma)/min/ml(tissue) versus 1.2+/-0.7x10(-3)ml(plasma)/min/ml(tissue); p=0.001). High-grade gliomas showed heterogeneous uptake with a mean K(i) of 7.7+/-4x10(-3)ml(plasma)/min/ml(tissue). A threshold K(i)(mean) of 1.8x10(-3) differentiates between normal tissue and tumour (sensitivity 84%, specificity 88%); however, the latter threshold underestimated the extent of tumour in half the cases. SUV closely agreed with K(i) measurements., Conclusion: FLT PET is a useful marker of cellular proliferation that correlates with regional variation in cellular proliferation; however, it is unable to identify the margin of gliomas.

Published
2009
Full Text
View/download PDF

42. Decision-making in mania: a PET study.

Author

Rubinsztein JS, Fletcher PC, Rogers RD, Ho LW, Aigbirhio FI, Paykel ES, Robbins TW, and Sahakian BJ

Subjects
Adult, Gyrus Cinguli physiopathology, Humans, Middle Aged, Prefrontal Cortex physiopathology, Bipolar Disorder diagnostic imaging, Bipolar Disorder physiopathology, Decision Making physiology, Tomography, Emission-Computed
Abstract

Poor decision-making is often observed clinically in the manic syndrome. In normal volunteers, decision-making has been associated with activation in the ventral prefrontal cortex and the anterior cingulate gyrus. The aim of this study was to evaluate task-related activation in bipolar manic patients in these regions of the prefrontal cortex using PET. Six subjects with mania, 10 controls and six subjects with unipolar depression (an affective patient control group) were scanned using the bolus H(2)(15)O method while they were performing a decision-making task. Activations associated with the decision-making task were observed at two levels of difficulty. Task-related activation was increased in the manic patients compared with the control patients in the left dorsal anterior cingulate [Brodmann area (BA) 32] but decreased in the right frontal polar region (BA 10). In addition, controls showed greater task-related activation in the inferior frontal gyrus (BA 47) than manic patients. A positive correlation (r(s) = 0.88) between task-related activation in the anterior cingulate and increasing severity of manic symptoms was found. Depressed patients did not show significant task-related differences in activation compared with control subjects in the regions of interest. In conclusion, these patterns of activation point to abnormal task-related responses in specific frontal regions in manic patients. Moreover, they are consistent with neuropsychological observations in patients with lesions in the ventromedial prefrontal cortex, who show similar difficulties with decision-making and provide early evidence for context-specific neural correlates of mania.

Published
2001
Full Text
View/download PDF

44. Syntheses of the first endothelin-A- and -B-selective radioligands for positron emission tomography.

Author

Johnström P, Aigbirhio FI, Clark JC, Downey SP, Pickard JD, and Davenport AP

Subjects
Amino Acid Sequence, Humans, Ligands, Molecular Sequence Data, Receptor, Endothelin A, Receptor, Endothelin B, Carbon Radioisotopes, Dioxoles chemical synthesis, Endothelins chemical synthesis, Fluorine Radioisotopes, Peptide Fragments chemical synthesis, Receptors, Endothelin analysis, Tomography, Emission-Computed
Abstract

We have synthesized two potential positron emission tomography (PET) radioligands for the endothelin (ET) receptor. [11C]-PD156707 was produced by O-methylation of PD169390 using [11C]iodomethane. Radiochemical conversions of the order of 74 +/- 3.2% (n = 8) were obtained. The radiochemical purity of the isolated [11C]-PD156707 was 99% and the specific activity was 538 mCi/micromol. [18F]-BQ3020 was produced from [18F]fluoride in a total radiochemical yield of 2.7 +/- 0.4% (n = 10) in 238 +/- 5 min. The radiochemical purity was 95% and specific activities of the order of 670-930 mCi/micromol were obtained.

Published
2000
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results