1
|
Herr W, Stöcklin G, Schmidt F. Über die Wirkung von Amin-Zusätzen auf Größe und Zusammensetzung der 82Br-Retention in neutronenbestrahltem n- und iso-Propylbromid. ACTA ACUST UNITED AC 2014. [DOI: 10.1515/znb-1959-1101] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Mit Hilfe radio-gaschromatographischer Methoden wurde die Wirkung von zahlreichen Aminen auf die retendierte 82Br-Aktivität in neutronenbestrahltem n- und iso-Propylbromid untersucht. Während tertiäre Amine beim n-Propylbromid eine beträchtliche Retentions-Erhöhung hervorrufen, bewirken alle untersuchten Aminzusätze beim iso-Propylbromid eine Retentions-Erniedrigung. Der Betrag der Retentions-Erniedrigung scheint weitgehend der chemischen Reaktionsfähigkeit der Amine mit dem bestrahlten Propylbromid zu entsprechen. Die bemerkenswerte Retentions-Erhöhung durch tertiäre Amine beim n-Propylbromid ist um so größer, je stärker ausgeprägt sein Quartärnisierungs-Vermögen mit n-Propylbromid ist. Gerade hier sollte jedoch nach dem Formalismus der Hofmann sehen Reaktion eine Retentions-Erniedrigung erwartet werden. Die durch tertiäre Amine hervorgerufene Retentions-Erhöhung drückt sich hauptsächlich in der vermehrten Bildung der 82Br-markierten Muttermoleküle aus, die in diesem Falle bis zu 90% der induzierten Gesamtaktivität ausmacht.
Eine Deutung dieser Retentions-Erhöhung kann über die Annahme eines dissoziativen Austausches gegeben werden, der nur beim Zusatz tertiärer Amine zu einer Retentions-Erhöhung führen kann. Es wird weiterhin festgestellt, daß die individuellen 82Br-Reaktionsprodukte stark von der Konstitution des zugesetzten Amins abhängig sind. Eine durch die ionisierende Strahlung im Reaktor bewirkte Retentions-Erhöhung wird durch einen geringen Zusatz von primären aromatischen Aminen weitgehend vermieden.
Das Auftreten von ungesättigten 82Br-Rückstoßverbindungen wie Vinylbromid, 1-Brompropen-l und 2-Brompropen-1 wird beim n-Propylbromid nur in Gegenwart von aromatischen Aminen beobachtet. Unter unseren Bestrahlungsbedingungen (2 Stdn. bei 2,6·1011 n/cm2 sec) jedoch nicht beim reinen n-Propylbromid.
Eine Unterscheidung zwischen den auf „heißem“ und den auf „thermischem“ Wege entstandenen Anteilen der Rückstoßprodukte läßt sich mit Amin-scavengern nicht ohne weiteres treffen.
Collapse
Affiliation(s)
- W. Herr
- Max-Planck-Institut für Chemie, Mainz
| | | | | |
Collapse
|
2
|
Wüst F, Reul JMHM, Rein T, Abel A, Stöcklin G. Pet-corticosteroids as potential ligands for mapping brain glucocorticoid receptors (GR). J Labelled Comp Radiopharm 2012. [DOI: 10.1002/jlcr.2580440105] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
3
|
|
4
|
Engelskirchen G, Hamacher K, Coenen H, Stöcklin G. Optimization studies of the aminopolyether supported nucleophilic [18F]FDG synthesis. J Labelled Comp Radiopharm 2011. [DOI: 10.1002/jlcr.25802601193] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
5
|
|
6
|
Affiliation(s)
- G. Stöcklin
- Arbeitsgruppe „Institut für Radiochemie" KernforschungsanJage Jülich und Institut für Kernchemie der Universität Köln
| | - W . Tornau
- Arbeitsgruppe „Institut für Radiochemie“ KernforschungsanJage Jülich und Institut für Kernchemie der Universität Köln
| |
Collapse
|
7
|
Affiliation(s)
- G. Stöcklin
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - S. M. Qaim
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - F. Rösch
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| |
Collapse
|
8
|
Moerlein SM, Laufer P, Stöcklin G. Synthesis of no-carrier-added radiobrominated N-alkylated analogues of spiperone. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.2580221004] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
9
|
|
10
|
|
11
|
Karim HMA, Stöcklin G. Fluorine-18 labelling of lower fatty acid esters by heterogeneous exchange on gas chromatographic columns. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.2580130409] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
12
|
|
13
|
Coenen HH, Machulla HJ, Stöcklin G. Practically carrier-free labelling of aromatic compounds with bromine-77 via N-chloro-tetrafluorosuccinimide. J Labelled Comp Radiopharm 2006. [DOI: 10.1002/jlcr.2580160612] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
14
|
Stöcklin G, Stangl H, Christman DR, Cumming JB, Wolf AP. THE REACTIONS OF ENERGETIC CARBON ATOMS IN METHANE; OXYGEN AND PHASE DEPENDENCE; RADIATION DAMAGE EFFECTS1. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100802a513] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
15
|
Patt M, Sorger D, Scheunemann M, Stöcklin G. FDG-2-nitroimidazole: A new potential hypoxia tracer using glucose transport. J Labelled Comp Radiopharm 2001. [DOI: 10.1002/jlcr.25804401137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
16
|
Matsunari I, Haas F, Nguyen NT, Reidel G, Wolf I, Senekowitsch-Schmidtke R, Stöcklin G, Schwaiger M. Comparison of sestamibi, tetrofosmin, and Q12 retention in porcine myocardium. J Nucl Med 2001; 42:818-23. [PMID: 11337582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
UNLABELLED Although there are several 99mTc perfusion tracers introduced for clinical use, there are no data available directly comparing these tracers with microsphere-determined flow. The aim of this study was to compare the myocardial retention of sestamibi, tetrofosmin, and Q12 in a porcine model. METHODS We used a pig model with (n = 6) or without (n = 3) coronary occlusion. Each pig received a simultaneous injection of sestamibi and either tetrofosmin (group 1, n = 5) or Q12 (group 2, n = 4) labeled with either 99mTc or 95mTc (physical half-life, 61 d; photon energy, 204 keV) during pharmacologic vasodilation. Absolute myocardial retention of each tracer was calculated from the myocardial tracer activity and arterial input function. RESULTS The plot of all three tracers versus flow achieved a plateau at a higher flow range. However, sestamibi showed a higher mean retention than either tetrofosmin (group 1, 0.27 +/- 0.11 vs. 0.16 +/- 0.06 mL/g/min, respectively; P < 0.01) or Q12 (group 2, 0.32 +/- 0.13 vs. 0.09 +/- 0.03 mL/g/min, respectively; P < 0.01). Furthermore, when a linear regression analysis was performed to assess the relationship between retention and microsphere-determined flow, sestamibi showed a greater increment in retention than did tetrofosmin or Q12. CONCLUSION Although all of the tracers showed a nonlinear increase in retention as flow increased, sestamibi may display more favorable characteristics as a flow tracer in the porcine heart.
Collapse
Affiliation(s)
- I Matsunari
- Department of Nuclear Medicine, Technische Universität München, Klinikum rechts der Isar, Germany
| | | | | | | | | | | | | | | |
Collapse
|
17
|
Weber WA, Wester HJ, Grosu AL, Herz M, Dzewas B, Feldmann HJ, Molls M, Stöcklin G, Schwaiger M. O-(2-[18F]fluoroethyl)-L-tyrosine and L-[methyl-11C]methionine uptake in brain tumours: initial results of a comparative study. Eur J Nucl Med 2000; 27:542-9. [PMID: 10853810 DOI: 10.1007/s002590050541] [Citation(s) in RCA: 307] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
O-(2-[18F]Fluoroethyl)-L-tyrosine (FET) is a recently described amino acid analogue that has shown high accumulation in animal tumours. The aim of this study was to compare the uptake of FET with that of L-[methyl-11C]methionine (MET) in patients with suspected primary or recurrent intracerebral tumours. Sixteen consecutive patients with intracerebral lesions were studied on the same day by positron emission tomography (PET) using MET and FET. Uptake of FET and MET was quantified by standardized uptake values. Tracer kinetics for normal brain and intracerebral lesions were compared. On the basis of the MET-PET studies, viable tumour tissue was found in 13 patients. All tumours showed rapid uptake of FET and were visualized with high contrast. Mean uptake of FET for normal grey matter, white matter and tumour tissue was 1.1+/-0.2, 0.8+/-0.2 and 2.7+/-0.8 SUV, respectively. In all three tissues, uptake of MET was slightly higher (1.4+/-0.2, 0.9+/-0.1 and 3.3+/-1.0 SUV; P<0.01). However, contrast between tumour and normal tissues was not significantly different between MET and FET. Uptake of FET in non-neoplastic lesions (1.0+/-0.1 SUV) was significantly lower than in tumour tissue (P = 0.007). For all lesions there was a close correlation (r = 0.98) between MET and FET uptake. In conclusion, in PET studies of human brain tumours, the uptake and image contrast of FET appear to be very similar to those of MET. The specificity of FET for tumour tissue is promising but has to be addressed in a larger series of patients with non-neoplastic lesions.
Collapse
Affiliation(s)
- W A Weber
- Department of Nuclear Medicine, Technische Universität München, Germany.
| | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Stöcklin G, Cacace F. Im Memoriam Alfred P. Wolf. RADIOCHIM ACTA 2000. [DOI: 10.1524/ract.2000.88.3-4.121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Dr. Alfred P. Wolf, Al, died on 17 December 1998. A great scientist has left us, whose 47 years´ service in the field of radioisotope applications in organic chemistry, hot atom chemistry, and radiopharmaceutical chemistry had a tremendous impact on applied radiochemsitry and nuclear medicine.
Collapse
|
19
|
Haubner R, Wester HJ, Reuning U, Senekowitsch-Schmidtke R, Diefenbach B, Kessler H, Stöcklin G, Schwaiger M. Radiolabeled alpha(v)beta3 integrin antagonists: a new class of tracers for tumor targeting. J Nucl Med 1999; 40:1061-71. [PMID: 10452325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023] Open
Abstract
UNLABELLED The alpha(v)beta3 integrins play an important role during tumor metastasis and tumor-induced angiogenesis. Targeting of this receptor may provide information about the receptor status of the tumor and enable specific therapeutic planning. Cyclo(-Arg-Gly-Asp-D-Phe-Val-) has been shown to be a selective alpha(v)beta3 integrin antagonist with high affinity. In this study we describe the synthesis and biological evaluation of [125I]-3-iodo-D-Tyr4-cyclo(-Arg-Gly-Asp-D-Tyr-Val-) ([125I]P2), [125I]-3-iodo-Tyr5-cyclo(-Arg-Gly-Asp-D-Phe-Tyr-) ([125I]P4) and the negative control peptide [1251]-3-iodo-D-Tyr4-cyclo(-Arg-D-Ala-Asp-Tyr-Val-) ([125I]P6). METHODS Peptides were assembled on a solid support using fluorenylmethoxycarbonyl amino acid coupling protocols. Radioiodination was performed using the iodogen method. The in vitro binding assays were performed using isolated, immobilized alphaIIbeta3 and alpha(v)beta3 integrins. Expression of the alphaVbeta3 receptor on the different tumors was validated by immunohistochemical methods using alpha(v) and alpha(v)beta3 specific antibodies. For biodistribution studies, nude mice with melanoma M21 or mammary carcinoma MaCaF and BALB/c mice with osteosarcoma were used. RESULTS The in vitro binding assays demonstrate that the introduction of tyrosine and subsequent iodination have no influence on the high affinity and selectivity for alpha(v)beta3. Immunohistochemical staining clearly indicates the presence of the alpha(v)beta3 integrins on the tumor tissue of the melanoma and the osteosarcoma. Pretreatment and displacement studies show specific binding of [125I]P2 on melanoma M21-bearing nude mice and osteosarcoma-bearing BALB/c mice but less specific binding on mammary carcinomas. [125I]P2 exhibits fast elimination kinetics. The accumulation in the tumor 10 min postinjection is 2.07 +/- 0.32 %ID/g for the melanoma M21 and 3.50 +/- 0.49 %ID/g for the osteosarcoma and decreases to 1.30 +/- 0.13 %ID/g and 2.03 +/- 0.49 %ID/g 60 min postinjection, respectively. [125I]P4 shows even faster elimination kinetics, resulting in a tumor accumulation of 0.40 +/- 0.10 %ID/g 60 min postinjection for the osteosarcoma-bearing BALB/c mice. Both peptides reveal predominately hepatobiliary excretion. For [1251]P2, this also is confirmed by autoradiography. The negative control peptide [125I]P6 shows no specific activity accumulation. CONCLUSION [125I]P2 exhibits high affinity and selectivity for the alpha(v)beta3 integrin in vitro and in vivo and, thus, represents the first radiolabeled alpha(v)beta3 antagonist for the investigation of angiogenesis and metastasis in vivo.
Collapse
Affiliation(s)
- R Haubner
- Department of Nuclear Medicine, Women's Hospital, Institute of Organic Chemistry and Biochemistry, Technische Universität München, Munich, Germany
| | | | | | | | | | | | | | | |
Collapse
|
20
|
Wester HJ, Herz M, Senekowitsch-Schmidtke R, Schwaiger M, Stöcklin G, Hamacher K. Preclinical evaluation of 4-[18F]fluoroprolines: diastereomeric effect on metabolism and uptake in mice. Nucl Med Biol 1999; 26:259-65. [PMID: 10363796 DOI: 10.1016/s0969-8051(98)00107-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
The aim of this study was to evaluate the diastereomeric effect on uptake and metabolic behavior of (2S,4R)-4-[18F]fluoro-L-proline (trans-[18F]FPro) and (2S,4S)-4-[18F]fluoro-L-proline (cis-[18F]FPro) in view of their potential suitability as tracers for abnormal collagen synthesis. No-carrier-added 4-[18F]fluoro-L-prolines were prepared according to the literature in about 150 min (50-60% radiochemical yield). Both compounds exhibited high in vivo stability. The tumor uptake of cis-[18F]FPro in osteosarcomas of mice was high and at 240 min postinjection reached 11.8 +/- 2.2 %ID/g compared with 7.07 +/- 1.68 %ID/g for trans-[18F]FPro. In contrat to trans-[18F]FPro, which showed fast and complete renal clearance, the cis isomer was accumulated in the pancreas, and showed hepatic clearance and renal reuptake. Speciation studies on tissue homogenates revealed protein incorporation only for cis-[18F]FPro. However, due to the relatively slow protein incorporation rate of cis-[18F]FPro, the tumor uptake of both compounds in colon carcinomas, mammary carcinomas, and osteosarcomas 1 h postinjection predominantly reflect amino acid transport.
Collapse
Affiliation(s)
- H J Wester
- Department of Nuclear Medicine, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | | | | | | | | | | |
Collapse
|
21
|
Wester HJ, Herz M, Weber W, Heiss P, Senekowitsch-Schmidtke R, Schwaiger M, Stöcklin G. Synthesis and radiopharmacology of O-(2-[18F]fluoroethyl)-L-tyrosine for tumor imaging. J Nucl Med 1999; 40:205-12. [PMID: 9935078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023] Open
Abstract
UNLABELLED The aim of the study was to develop a simple 18F-labeled amino acid as a PET tracer for cerebral and peripheral tumors. O-(2-[18F]fluoroethyl)-L-tyrosine (L-[18F]FET) was synthesized and biologically evaluated. Results of the first human PET study are reported. METHODS No carrier added (n.c.a.) and D-[18F]FET were prepared by 18F-fluoroethylation of L- and D-tyrosine in a two-step procedure. Biodistribution studies were performed in mice. The metabolic fate of L-[18F]FET was investigated in plasma, brain, tumor and pancreatic tissue samples using chromatographic procedures. Tumor uptake studies were performed in mammary carcinoma-bearing mice and in mice with the colon carcinoma SW 707. In a human PET study, a 59-y-old man with a recurrent astrocytoma was imaged using n.c.a. L-[18F]FET. RESULTS Synthesis of [18F]FET was accomplished in about 50 min with an overall radiochemical yield of 40%. The uptake of L-[18F]FET in the brain of mice reached a level >2% ID/g between 30 and 60 min postinjection. The brain uptake of the D-isomer was negligible, indicating blood-brain barrier penetration by a specific amino acid transport system. L-[18F]FET is not incorporated into proteins. High-performance liquid chromatography (HPLC) analysis of brain, pancreas and tumor homogenates as well as plasma samples of mice at 10, 40 or 60 min postinjection showed only unchanged L-[18F]FET. Activity uptake in the bone did not exceed 2% ID/g at 40 min postinjection. The brain uptake of L-[18F]FET in mice bearing mammary carcinomas and colon carcinomas reached 7.1%+/-1.2% ID/g and 6.4%+/-1.7% ID/g 1h postinjection, respectively. In the first human study, L-[18F]FET-PET allowed a clear delineation of a recurrent astrocytoma. Thirty-five minutes postinjection, the tumor-to-cortex ratio was >2.7. A tumor-to-blood ratio >1.5 was reached at 30 min postinjection and continued to increase. No significant activity accumulation was observed in peripheral organs after approximately 40 min postinjection. CONCLUSION The high in vivo stability of L-[18F]FET, its fast brain and tumor uptake kinetics, its low accumulation in nontumor tissue and its ease of synthesis strongly support further evaluation of L-[18F]FET as an amino acid tracer for cerebral and peripheral tumors.
Collapse
Affiliation(s)
- H J Wester
- Department of Nuclear Medicine, Klinikum Rechts der Isar, Technischer Universität München, Munich, Germany
| | | | | | | | | | | | | |
Collapse
|
22
|
Boy C, Klimke A, Holschbach M, Herzog H, Mühlensiepen H, Rota Kops E, Sonnenberg F, Gaebel W, Stöcklin G, Markstein R, Müller-Gärtner HW. Imaging dopamine D4 receptors in the living primate brain: a positron emission tomography study using the novel D1/D4 antagonist [11C]SDZ GLC 756. Synapse 1998; 30:341-50. [PMID: 9826226 DOI: 10.1002/(sici)1098-2396(199812)30:4<341::aid-syn1>3.0.co;2-6] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The dopamine D4 receptor has lately attracted interest since it has been hypothesized to be involved in the pathogenesis and pharmacotherapy of neuropsychiatric diseases. The present study provides first in vivo evidence of dopamine D4 receptors in primate brain using a [11C]benzo[g]quinoline, the novel radioligand [11C]SDZ GLC 756 ([11C]GLC: in vitro dissociation constants at human receptor clones [nM]: 1.10 at D1; 0.40 at D2; 25 at D3; 0.18 at D4.2; 6.03 at D5). Dynamic positron emission tomography scans were performed on healthy baboons (Papio hamadryas, n = 3). Specific receptor binding (SB) was calculated for striatum and neocortex (frontal, temporal, parietal, and occipital) based on the differences between the regional and the cerebellar concentration of [11C]. Blockade of D1 and D5 receptors by SCH23390 (1.7 pmol/kg) diminished SB in the striatum by 55 +/- 4% (mean +/- standard deviation, P < 0.05) and in the frontal cortex by 13 +/- 8% (P < 0.05) when compared to SB in the unblocked state (SB(D1-D5)). In the presence of the dopamine antagonists SCH23390 (1.7 micromol/kg) and raclopride (5.7 pmol/kg)--which mask the D1, D2, D3, and D5 subtypes--SB of [11C]GLC to D4 receptors (SB(D4)) was demonstrated in the striatum and all cortical regions of interest. In the striatum, the ratio of SB(D4)/SB(D1-D5) was 0.13 +/- 0.07. In the neocortex, SB(D4)/SB(D1-D5) was notably higher (0.77 +/- 0.29; mean of all cortical regions of interest). The widespread distribution of dopamine D4 receptors suggests a basic functional role of this receptor subtype in the modulation of cortical and subcortical neuronal activity.
Collapse
Affiliation(s)
- C Boy
- Institute of Medicine, Research Center Jülich, Germany
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Klimke A, Boy C, Eickhoff M, Herzog H, Holschbach M, Mühlensiepen H, Weckessec M, Rota-Kops E, Sonnenberg F, Gaebel W, Markstein R, Stöcklin G, Coenen H, Müller-Gärtner H. Dopamine D 1 and D 4-like receptors in untreated schizophrenic patients and healthy controls. Eur Psychiatry 1998. [DOI: 10.1016/s0924-9338(99)80289-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
|
24
|
Holschbach M, Hamkens W, Steinbach A, Hamacher K, Stöcklin G. [13N]Cisplatin: a fast and efficient on-line synthesis using a solid state support. Appl Radiat Isot 1997. [DOI: 10.1016/s0969-8043(96)00323-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
25
|
Wester HJ, Brockmann J, Rösch F, Wutz W, Herzog H, Smith-Jones P, Stolz B, Bruns C, Stöcklin G. PET-pharmacokinetics of 18F-octreotide: a comparison with 67Ga-DFO- and 86Y-DTPA-octreotide. Nucl Med Biol 1997; 24:275-86. [PMID: 9257325 DOI: 10.1016/s0969-8051(97)00039-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
The quantitative uptake kinetics of (2-[18F]fluoropropionyl-(D)phe1)-octreotide (I), a somatostatin (SRIF) receptor-specific tracer, was measured by PET. Conventional organ biodistribution and in vivo stabilities of the tracer as well as in vivo displacement and SRIF receptor blocking were determined. The 18F-fluorinated octreotide was compared with ([67Ga]-DFO-B-succinyl-(D)phe1)-octreotide (II) and ([86Y]-DTPA-(D)phe1)-octreotide (III). Initially, 2-10 MBq of the labeled tracers were injected into male Lewis rats bearing an exocrine pancreatic islet cell tumor. PET measurements were performed dynamically between 0 and 120 min postinjection. Organ distributions were determined 5, 15, 30, 60, and 120 min postinjection. The extent of metabolic degradation was analyzed in serial blood and urine samples as well as in homogenized samples of tumor, liver, and kidney. The uptake of (I) by the tumor was rapid (maximum accumulation at 1-2 min postinjection) and high (about 0.5 +/- 0.2% ID/g), followed by a fast and continuous release with koff = 10 +/- 2. 10(-5) s-1. The tracer was found to remain intact in vivo up to 120 min postinjection. Specific binding of (I) to SRIF receptors in the adrenals, the pancreas, and the pituitary gland was demonstrated in vivo by pretreatment and displacement experiments. Compound (II) also showed a fast uptake by the tumor. Its tumor residence half-life was longer (koff = 3.0 +/- 0.5 . 10(-5) s-1). Compound (II) was also predominantly excreted intact. One hour postinjection, the remaining activity in the blood pool was found to be bound to serum proteins. Early uptake kinetics for compound (III) were also rapid but reached only half the tumor uptake of (II). Compared to (I), the release of 86Y-activity from the tumor was slower (koff = 3.1 +/- 1.3 . 10(-5) s-1). Compared to (II), compound (III) was considerably less stable in vivo. The main critical organs for (II) and (III) are kidneys and bones, whereas (I) is predominantly accumulated in the liver. The in vivo behavior of (I) closely resembles 14C-labeled octreotide. Thus, 18F-labeled octreotide may be of interest in the quantitation and investigation of in vivo properties of somatostatin receptors by PET. However, the short residence of (2-[18F]fluoropropionyl-(D)phe1)-octreotide in tumors and its hepatobiliary excretion may complicate the interpretation of abdominal tumors.
Collapse
Affiliation(s)
- H J Wester
- Institute für Nuklearchemie, KFA Julich, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
26
|
Langen KJ, Ziemons K, Kiwit JC, Herzog H, Kuwert T, Bock WJ, Stöcklin G, Feinendegen LE, Müller-Gärtner HW. 3-[123I]iodo-alpha-methyltyrosine and [methyl-11C]-L-methionine uptake in cerebral gliomas: a comparative study using SPECT and PET. J Nucl Med 1997; 38:517-22. [PMID: 9098193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
UNLABELLED This study compares the uptake of the nonmetabolizable amino acid analog 3-[123I]iodo-alpha-methyltyrosine (IMT) and of [methyl-11C]-L-methionine (MET) in cerebral gliomas. METHODS In 14 patients with cerebral gliomas, IMT uptake was measured using SPECT (10 dynamic, 4 static SPECT acquisitions) and, on the same day, MET uptake by dynamic PET. The IMT and MET data were compared with respect to tracer kinetics, tumor to brain ratios (T/B) and tumor size after converting the resolution of the PET scans to that of the SPECT scans (14 mm FWHM). RESULTS All gliomas showed increased uptake of both tracers in relation to normal brain tissue. Visual comparison of the scans yielded no differences in tumor size and shape with both methods. IMT showed a maximal tracer uptake in brain and in tumors at about 15 min postinjection which was followed by a washout of 45.0% +/- 13.5% in gliomas (mean +/- s.d., p < 0.001, n = 10) and 35.3% +/- 5.4% in normal brain (p < 0.001, n = 10) at 60 min postinjection. MET concentration in tumor tissue or brain tissue between 15 and 60 min remained constant. T/B ratios of IMT SPECT and MET PET showed a significant correlation at 15 min postinjection (r = 0.69, n = 10, p = 0.03), a low correlation for the mean values of the scans from 15-60 min postinjection (r = 0.54, n = 14, p = 0.05) and no correlation at 60 min postinjection (r = 0.09, n = 10, n.s.). CONCLUSION IMT and MET uptake in gliomas is similar in the early, transport dominated phase. There are some differences in tumor to brain ratios between both tracers within the first hour postinjection that are mainly caused by variable washout of IMT. Imaging of tumor extent with IMT SPECT is comparable to MET PET. Thus, amino acid SPECT using IMT is a promising tool to evaluate the biological activity and intracerebral infiltration of gliomas.
Collapse
Affiliation(s)
- K J Langen
- Institute of Medicine, Research Center Jülich, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Rösch F, Herzog H, Plag C, Neumaier B, Braun U, Müller-Gärtner HW, Stöcklin G. Radiation doses of yttrium-90 citrate and yttrium-90 EDTMP as determined via analogous yttrium-86 complexes and positron emission tomography. Eur J Nucl Med 1996; 23:958-66. [PMID: 8753686 DOI: 10.1007/bf01084371] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Yttrium-90 is used for palliative therapy for the treatment of skeletal metastases, but because it is a pure beta- emitter, data on the pharmacokinetics and radiation doses to metastases and unaffected organs are lacking. To obtain such data, the present study employed yttrium-86 as a substitute for 90Y, with detection by positron emission tomography (PET). The study compared the properties of two different 86Y complexes - 86Y-citrate and 86Y-ethylene diamine tetramethylene phosphonate (EDTMP) - in ten patients with prostatic cancer who had developed multiple bone metastases (the ten patients being divided into two groups of five). Early dynamics were measured up to 1 h post injection (p.i.) over the liver region, followed by subsequent whole-body PET scans up to 3 days p.i. Absolute uptake data were determined for normal bone, bone metastases, liver and kidney. Radiation doses were calculated according to the MIRD recommendations. Based on the pharmacokinetic measurements of the distribution of the 86Y complexes, it was possible to calculate radiation doses for the bone metastases and the red bone marrow delivered by complexes containing 90Y. In 1 cm3 of bone metastasis, doses of 26+/-11 mGy/MBq and 18+/-2 mGy/MBq were determined per MBq of injected 90Y-citrate and 90Y-EDTMP, respectively. The doses to the bone marrow were 2.5+/-0.4 mGy/MBq for 90Y-citrate and 1.8+/-0.6 mGy/MBq for 90Y-EDTMP. 86Y and PET provide quantitative information applicable to the clinical use of 90Y. This method may also be useful for the design of other 90Y radiopharmaceuticals and for planning radiotherapy dosages.
Collapse
Affiliation(s)
- F Rösch
- Institut für Nuklearchemie, Forschungszentrum Jülich, Jülich, Germany
| | | | | | | | | | | | | |
Collapse
|
28
|
|
29
|
Abstract
Three methods for 18F-labeling of proteins were evaluated with respect to conjugation yields, suitability for remote-controlled routine synthesis, and in vivo stability of the conjugates-i.e., photochemical conjugation (PCC) using 4-azidophenacyl-[18F]fluoride ([18F]APF) as well as classical conjugation using 4-nitrophenyl 2-[18F]fluoropropionate ([18F]NPFP) and N-succinimidyl 4-[18F]fluorobenzoate ([18F]SFB). For this purpose, [18F]APF was synthesized in one step with a radiochemical yield (RCY) of up to 70% within about 15 min. The 18F-labeling was performed by photogeneration of the corresponding [18F]arylnitrene by irradiating [18F]APF with UV light in presence of the protein in aqueous buffered solution. Using this procedure, human serum albumin (HSA), transferrin, IgG, and avidin were labeled. The [18F]NPFP was synthesized according to a recently published method. Preparation of [18F]SFB was achieved within 35 min with radiochemical yields of 55 +/- 10% by an improved method using O-(N-succinimidyl)-N-N,N',N'-tetramethyluronium tetrafluoroborate (TSTU) as activating reagent. Compared to [18F]APF, protein labeling with [18F]NPFP and [18F]SFB gave rise to considerably higher RCY, of up to 90%. Labeling studies showed that conjugation yields using [18F]NPFP depend on the lysine, tyrosine, and histidine content of the proteins used, whereas conjugation with [18F]APF and [18F]SFB predominantly depends on the Lys content. Owing to competing O-acylation of Tyr residues, [18F]fluoropropionylated HSA was partially unstable under slightly basic conditions. Biodistribution studies with 18F-labeled HSA in NMRI mice revealed the highest in vivo stability for the [18F]SFB conjugate. Based on these results, [18F]SFB seems to be the most suitable 18F-labeling agent for proteins, particularly for the labeling of antibodies.
Collapse
Affiliation(s)
- H J Wester
- Institut für Nuklearchemie, Forschungszentrum Jülich GMBH, Germany
| | | | | |
Collapse
|
30
|
Schlaug G, Hefter H, Engelbrecht V, Kuwert T, Arnold S, Stöcklin G, Seitz RJ. Neurological impairment and recovery in Wilson's disease: evidence from PET and MRI. J Neurol Sci 1996; 136:129-39. [PMID: 8815159 DOI: 10.1016/0022-510x(95)00293-b] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
We studied the relationship of regional cerebral glucose consumption (rCMRGlc) and striatal dopamine D2 receptor binding as assessed with positron emission tomography (PET) with the structural abnormalities of the brain in magnetic resonance images (MR), and the degree of neurological impairment in 18 patients with Wilson's disease (WD). The rCMRGlc was determined in the basal ganglia, the thalamus, the cerebral cortex, and the cerebellar hemispheres. The severity of neurological signs, defined by semiquantitative motor impairment scores, correlated highly (r = -0.80) with the reduction of striatal rCMRGlc. Clinical scores, striatal rCMRGlc, and the degree of MRI abnormalities showed no correlation with different indices of dopamine D2 receptor binding. Sequential PET measurements in three patients during treatment with chelating agents revealed a moderate increase of striatal rCMRGlc (in two patients) and a moderate to marked increase of striatal D2 receptor binding (in three patients) in association with clinical improvement. Our data suggest that the rCMRGlc represents a sensitive and objective measure for assessing and monitoring striatal and extrastriatal involvement in WD. The lack of correlation between the dopamine D2 receptor binding and striatal rCMRGlc and structural abnormalities may be explained by the wide spectrum of clinical manifestations and different responses to treatment in WD patients.
Collapse
Affiliation(s)
- G Schlaug
- Department of Neurology, Heinrich-Heine-University Düsseldorf, Germany
| | | | | | | | | | | | | |
Collapse
|
31
|
Affiliation(s)
- G. Stöcklin
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - S. M. Qaim
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - F. Rösch
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| |
Collapse
|
32
|
Bergmann R, Brust P, Kampf G, Coenen HH, Stöcklin G. Evaluation of radioselenium labeled selenomethionine, a potential tracer for brain protein synthesis by PET. Nucl Med Biol 1995; 22:475-81. [PMID: 7550024 DOI: 10.1016/0969-8051(94)00123-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The blood-brain transfer, protein incorporation and metabolism of L-[75Se]selenomethionine (SeMet) of relatively high specific activity (> 400 GBq mmol) were studied in male Wistar rats. The highest uptake was found in the pancreas, followed by the tumor, kidney, liver, brain and muscle. In addition, plasma and brain samples of rats were analyzed for labeled fractions of free SeMet, metabolites, and SeMet bound to t-RNA and proteins. For example, free SeMet represented more than 80% of brain radioactivity at 1.5 min while it was less than 15% at 360 min. A concomitant increase was observed for protein bound SeMet in brain. A three-compartment model was applied to calculate the blood-brain transfer constant (K1 (0.15 +/- 0.070 mL g-1 min-1) and the rate constant of SeMet incorporation into proteins (k3 = 0.026 +/- 0.008 min-1). The apparent incorporation of methionine into proteins was estimated to be about 0.73 nmol g-1 min-1. From the studies it is concluded that the use of L-[75Se]selenomethionine may be appropriate to measure brain protein incorporation in humans with PET.
Collapse
Affiliation(s)
- R Bergmann
- Forschungszentrum Rossendorf, Institut für Bioanorganische und Radiopharmazeutische Chemie, Dresden, Germany
| | | | | | | | | |
Collapse
|
33
|
Bender D, Holschbach M, Stöcklin G. Synthesis of n.c.a. carbon-11 labelled clozapine and its major metabolite clozapine-N-oxide and comparison of their biodistribution in mice. Nucl Med Biol 1994; 21:921-5. [PMID: 9234345 DOI: 10.1016/0969-8051(94)90080-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
N.c.a. [11C]clozapine, [8-chloro-11-(4-[methyl-11C]-methyl-1-piperazinyl)-5H-dibenzo[b,e]-1, 4-diazepine], 1, an atypical neuroleptic was synthesized by N-methylation of the desmethyl compound norclozapine, 3, using [11C]methyl iodide or [11C]methyl triflate for comparison. Subsequent oxidation of 1 with m-chloroperoxybenzoic acid yielded clozapine-N-oxide, 2, the major metabolite of 1. Purification of both radiolabelled products was carried out using a combined semi-preparative HPLC/solid phase extraction procedure. In preparative scale runs overall radiochemical yields for 1 and 2 were 70 and 65%, respectively. The radiochemical purities of both compounds exceeded 98% and the specific activities were in the range of 92-130 GBq/mumol (2.5-3.5 Ci/mumol). Biodistribution of 1 and 2 has been studied in NMRI mice. 10 min p.i. clozapine shows a 24-fold higher brain uptake than its major metabolite. At 60 min p.i., however, the cerebral uptake of both compounds is almost identical.
Collapse
Affiliation(s)
- D Bender
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, Germany
| | | | | |
Collapse
|
34
|
Schlaug G, Hefter H, Nebeling B, Engelbrecht V, Weiss P, Stöcklin G, Seitz RJ. Dopamine D2 receptor binding and cerebral glucose metabolism recover after D-penicillamine-therapy in Wilson's disease. J Neurol 1994; 241:577-84. [PMID: 7836960 DOI: 10.1007/bf00920620] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Regional cerebral glucose metabolism (rCMRGlc) and dopamine D2 receptor binding were measured in a 31-year-old, severely affected, untreated patient with Wilson's disease of 3 years' duration using positron emission tomography and 18F-deoxyglucose and 18F-methylspiperone ([18F]MSP), respectively. There was a severe reduction of striatal and extrastriatal rCMRGlc as well as of striatal [18F]MSP accumulation rate. After 1 year of treatment with D-penicillamine, striatal and extrastriatal rCMRGlc and striatal [18F]MSP accumulation rate reached almost normal levels. It is hypothesized that recovery of motor functions due to copper trapping therapy was associated with an increase in basal ganglia activity and a re-expression or upregulation of dopamine D2 receptors.
Collapse
Affiliation(s)
- G Schlaug
- Department of Neurology, Heinrich Heine University, Düsseldorf, Germany
| | | | | | | | | | | | | |
Collapse
|
35
|
Krummeich C, Holschbach M, Stöcklin G. Direct n.c.a. electrophilic radioiodination of tyrosine analogues; their in vivo stability and brain-uptake in mice. Appl Radiat Isot 1994; 45:929-35. [PMID: 7951181 DOI: 10.1016/0969-8043(94)90230-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
In order to improve tracers for amino acid transport studies with SPET we have radioiodinated methylated tyrosines and compared their brain uptake and in vivo deiodination in mice. O-methylation not only leads to a higher lipophilicity and hence significantly higher brain uptake with a maximum of 5% dose/g for 3-[123I]iodo-O-methyl-L-alpha-methyltyrosine (OMIMT) but also significantly prevents in vivo deiodination. High n.c.a. radioiodination yields (> or = 80%) are obtained for the activated aromatic compounds L-tyrosine and L-alpha-methyltyrosine using Iodo-gen iin a heterogeneous aqueous system. Direct n.c.a. radioiodination of the less-activated O-methyl analogues has been achieved in reasonable yields (60%) with Iodo-gen in homogeneous TFA solutions containing about 10% of water.
Collapse
Affiliation(s)
- C Krummeich
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, Germany
| | | | | |
Collapse
|
36
|
Guhlke S, Wester HJ, Bruns C, Stöcklin G. (2-[18F]fluoropropionyl-(D)phe1)-octreotide, a potential radiopharmaceutical for quantitative somatostatin receptor imaging with PET: synthesis, radiolabeling, in vitro validation and biodistribution in mice. Nucl Med Biol 1994; 21:819-25. [PMID: 9234331 DOI: 10.1016/0969-8051(94)90161-9] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Octreotide is labeled with fluorine-18 as a potential radiopharmaceutical for quantitative in vivo mapping of somatostatin receptors. [18F]-fluoroacylation is achieved with n.c.a. 2-[18F]fluoropropionic acid 4-nitrophenylester which is reacted with epsilon-Boc-Lys5-octreotide. After deprotection the desired N alpha-[18F]fluoropropionylated octreotide ([18F]SDZ 223-228) is obtained. Final HPLC purification gives rise to radiochemical yields of 65 +/- 5% based on the fluoroacylation agent. Binding experiments using rat cortex membranes indicate an affinity for somatostatin receptors of pKi = 8.6 +/- 0.2. The biological activity of this SRIF analog is demonstrated by the inhibition of growth hormone release from cultured pituitary cells. The pIC50 in this test system is 8.75, indicating full biological activity. Biodistribution studies with NMRI mice show predominantly renal excretion, rapid blood clearance and only negligible bone activity, i.e. formation of free fluoride.
Collapse
Affiliation(s)
- S Guhlke
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, Germany
| | | | | | | |
Collapse
|
37
|
Herzog H, Seitz RJ, Tellmann L, Schlaug G, Kleinschmidt A, Nebeling B, Stöcklin G, Müller-Gärtner HW. Pharmacokinetics and radiation dose of oxygen-15 labelled butanol in rCBF studies in humans. Eur J Nucl Med 1994; 21:138-43. [PMID: 8162937 DOI: 10.1007/bf00175761] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In this positron emission tomography (PET) study in humans we determined the pharmacokinetics and radiation dose of oxygen-15 labelled butanol, a recently introduced tracer for regional cerebral blood flow (rCBF). This report includes a description of the automated preparation of 15O-butanol which allows repetitive activation studies, each 15 min apart. Dynamic rCBF studies were extended by prolonged measurements up to 15 min after injection over different organs such as brain, liver, kidneys and bladder. All measurements were done with a whole-body PET camera PC4096-15WB. Based on the pharmacokinetic data in 13 subjects the radiation doses to single organs were calculated according to MIRD pamphlet No. 11 and the effective dose defined by ICRP 60 as an indicator of radiation dose to the total body. The liver received the highest radiation dose of about 2.2 mGy per 1500 MBq of injected 15O-butanol, which is the typical amount of administered tracer in one rCBF measurement. The dose to the kidneys was 1.6 mGy, to the stomach 0.8 mGy, and to the brain 0.16 mGy. The effective dose was 0.54 mGy, which was similar to that of H2(15)O, but lower than the effective dose from C15O2 in amounts typically applied in human rCBF studies.
Collapse
Affiliation(s)
- H Herzog
- Institute of Medicine, Research Center Jülich, Germany
| | | | | | | | | | | | | | | |
Collapse
|
38
|
Qaim S, Stöcklin G. Excitation functions of 74Se(d,xn)75,74mBr reactions: Comparative evaluation of possible routes for the production of 75Br at a small cyclotron. Appl Radiat Isot 1993. [DOI: 10.1016/0969-8043(93)90097-t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
39
|
Herzog H, Rösch F, Stöcklin G, Lueders C, Qaim SM, Feinendegen LE. Measurement of pharmacokinetics of yttrium-86 radiopharmaceuticals with PET and radiation dose calculation of analogous yttrium-90 radiotherapeutics. J Nucl Med 1993; 34:2222-6. [PMID: 8254415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
This study was performed to demonstrate the quantitative in vivo assessment of human pharmacokinetics of 90Y-radiotherapeutics using the positron-emitting substitute 86Y and PET. This technique is illustrated in a patient with disseminated bone metastases from breast cancer who was injected with 100 MBq of 86Y-citrate as an analog of the commercially available radiotherapeutic 90Y-citrate. Whole-body distribution was measured with a PET camera 4, 10, 21, 28 and 45 hr postinjection. Uptake data were determined from reconstructed transverse PET images by regions of interest placed in normal bone tissue, liver and metastases. Images of coronal and sagittal whole-body sections were obtained by reformatting the transverse PET images. The ratio of activity concentration in metastases to that in normal bone ranged from 1.5:1 to 3.5:1. Of the injected tracer, 13.4% was found in the skeleton and 0.43% in the metastasis with the highest 86Y concentration. Radiation doses per 1 MBq of injected 90Y-citrate were calculated from 86Y-citrate data and data from MIRD pamphlets 5 and 11. The doses were 1.01 MGy/MBq for red marrow, 593 microGy/MBq for the liver and approximately 3.5 MGy/MBq for the most conspicuous metastases. This study demonstrates that the use of PET via 86Y allows an individual in vivo quantification of activity uptake and radiation dose of both normal tissue and tumor in pain treatment with 90Y-labeled radiotherapeutics.
Collapse
Affiliation(s)
- H Herzog
- Institute of Medicine, Research Center Jülich, Germany
| | | | | | | | | | | |
Collapse
|
40
|
Scholten B, Qaim SM, Stöcklin G. A Systematic Study of (n,7Be) Reactions on Medium and Heavy Mass Nuclei Induced by 53 MeV d(Be)-Breakup Neutrons. ACTA ACUST UNITED AC 1993. [DOI: 10.1524/ract.1993.62.3.107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- B. Scholten
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany
| | - S. M. Qaim
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany (Received
| | - G. Stöcklin
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, D-52425 Jülich, Germany (Received
| |
Collapse
|
41
|
Katsifis A, Hamacher K, Schnitter J, Stöcklin G. Optimization studies concerning the direct nucleophilic fluorination of butyrophenone neuroleptics. Appl Radiat Isot 1993. [DOI: 10.1016/0969-8043(93)90005-u] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
42
|
|
43
|
Rösch F, Qaim SM, Stöcklin G. Nuclear Data Relevant to the Production of the Positron Emitting Radioisotope 86Y via the 86Sr(p,n)- and natRb(3He,xn)-Processes. ACTA ACUST UNITED AC 1993. [DOI: 10.1524/ract.1993.61.1.1] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- F. Rösch
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, W-5170 Jülich, Germany
- Bereich Radioaktive Isotope, ZfK Rossendorf, 0-8051 Dresden, Germany
| | - S. M. Qaim
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, W-5170 Jülich, Germany
| | - G. Stöcklin
- Institut für Nuklearchemie, Forschungszentrum Jülich GmbH, W-5170 Jülich, Germany
| |
Collapse
|
44
|
Deussen A, Henrich M, Hamacher K, Borst MM, Herzog H, Coenen HH, Stöcklin G, Feinendegen LE, Schrader J. Noninvasive assessment of regional cardiac adenosine using positron emission tomography. J Nucl Med 1992; 33:2138-44. [PMID: 1460505] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
One of the early metabolic changes associated with myocardial ischemia is the breakdown of adenine nucleotides resulting in the enhanced production of adenosine. In order to image regional cardiac adenosine by positron emission tomography (PET) the enzymatic conversion of adenosine into [11C]-S-adenosylhomocysteine ([11C]SAH) was used in the presence of 11C-labeled homocysteine thiolactone (adenosine + [11C] - homocysteine-->[11C] - SAH + H2O). Following production of an experimental coronary constriction in anesthetized dogs carrier added 1-[11C]-D,L-homocysteine thiolactone (5-27 mCi, 30 mg/kg) was infused over 1 min. This intervention, while hemodynamically ineffective, increased the plasma homocysteine concentration from 2.5 to 306 microM, which thereafter declined with a T1/2 of 28 min to 97 microM after 60 min. During the first minutes following infusion of [11C] homocysteine, the radioactivity concentration in the blood pool, the nonischemic and the ischemic myocardium were similar. Between 20 and 60 min, however, the regional radioactivity concentration was highest in the perfusion area of the stenosed vessel: 6.6% compared to 5.2 and 5.2% of the injected dose per 1 I tissue. The elevated radioactivity concentration was strictly confined to the perfusion area of the occluded artery. Using [35S]-L-homocysteine (20 microCi; 30 mg/kg) chromatographic separation of SAH in tissue extracts confirmed that the radioactivity accumulation was due to trapping of adenosine in the cellular SAH-pool. These experiments provide first evidence that 1-[11C]homocysteine thiolactone can be successfully used to assess regional adenosine formation in the heart with PET via measurement of [11C] SAH accumulation.
Collapse
Affiliation(s)
- A Deussen
- Zentrum für Physiologie, Heinrich-Heine-Universität Düsseldorf, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Gail R, Coenen HH, Hamacher K, Stöcklin G. 11C-labelling of the analgesic tramadol and its major metabolites by selective O- and N-methylation. Int J Rad Appl Instrum A 1992; 43:1129-37. [PMID: 1330990 DOI: 10.1016/0883-2889(92)90055-j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
For in vivo pharmacokinetic studies with PET, the analgesic Tramadol(1-(3-methoxyphenyl)-2-dimethylaminomethyl-cyclohexan-1-ol ) and its major O- and N-desmethylated metabolites M1 and M2 were labelled with carbon-11. Starting with the corresponding desmethyl precursors, (1R,2R)-(+), (1S,2S)-(-)-[O-methyl-11C]Tramadol and racemic-[N-methyl-11C]Tramadol were prepared by methylation with n.c.a. [11C]methyl iodide in DMSO with radiochemical yields of 85 and 90%, respectively. Specific n.c.a. N-methylation of bis-desmethyl-Tramadol (M5) was achieved without base obtaining 11C-labelled (1R,2R)-(+)- and (1S,2S)-(-)-M1 with 90% radiochemical yield. However, a selective O-methylation of (+)- and (-)-M5 was not possible even with an excess of NaOH, and only 70% of (1R,2R)-(+)- and (1S,2S)-(-)-[O-methyl-11C]M2 was obtained. Quaternization of Tramadol or M1 was greater than 15 times slower than O-methylation, and was only observed in the presence of added CH3I carrier.
Collapse
Affiliation(s)
- R Gail
- Institute für Nuklearchemie, Forschungszentrum Jülich GmbH, Germany
| | | | | | | |
Collapse
|
46
|
Affiliation(s)
- G Stöcklin
- Institut für Nuklearchemie, Forschungszentrum Jülich, Federal Republic of Germany
| |
Collapse
|
47
|
Stöcklin G. Anwendungen der Positronen-Emissions-Tomographie (PET) zur Messung regionaler zerebraler Pharmakokinetiken. Anasthesiol Intensivmed Notfallmed Schmerzther 1992; 27:84-92. [PMID: 1356493 DOI: 10.1055/s-2007-1000260] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Positron emission tomography (PET) has not only a variety of applications to functional diagnostics using methods of nuclear medicine and for the investigation of pathophysiological processes, it also offers new possibilities for pharmacology. As PET is able to quantitatively record "from outside" the regional concentration of a positron emitter in a living primate, the distribution and kinetics of a labelled drug at the site of action can be determined non-invasively. This is always the case if the research substance can be labelled practically carrier-free with a short-lived positron emitter such as 11C (T1/2 = 20 min) or if applicable 18F (T1/2 = 110 min). The quantities applied in this case are so small that pharmacodynamic effects do not occur. Therefore, this method is particularly suitable for measuring in vivo the regional cerebral pharmacokinetics of centrally acting drugs in humans.
Collapse
Affiliation(s)
- G Stöcklin
- Institut für Chemie, Forschungszentrum Jülich GmbH, Jülich
| |
Collapse
|
48
|
Piel H, Qaim SM, Stöcklin G. Excitation Functions of (p,xn)-Reactions on natNi and Highly Enriched 62Ni: Possibility of Production of Medically Important Radioisotope 62Cu at a Small Cyclotron. ACTA ACUST UNITED AC 1992. [DOI: 10.1524/ract.1992.57.1.1] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Heike Piel
- Institut fur Nuklearchemie, Forschungszentrum Jülich GmbH, D-5170 Jülich, Federal Republic of Germany
| | - S. M. Qaim
- Institut fur Nuklearchemie, Forschungszentrum Jülich GmbH, D-5170 Jülich, Federal Republic of Germany
| | - G. Stöcklin
- Institut fur Nuklearchemie, Forschungszentrum Jülich GmbH, D-5170 Jülich, Federal Republic of Germany
| |
Collapse
|
49
|
Karbe H, Wienhard K, Hamacher K, Huber M, Herholz K, Coenen HH, Stöcklin G, Lövenich A, Heiss WD. Positron emission tomography with (18F)methylspiperone demonstrates D2 dopamine receptor binding differences of clozapine and haloperidol. J Neural Transm (Vienna) 1991; 86:163-73. [PMID: 1837996 DOI: 10.1007/bf01250702] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Four schizophrenic patients were investigated with dynamic positron emission tomography (PET) using (18F)fluorodeoxyglucose (FDG) and (18F)methylspiperone (MSP) as tracers. Two schizophrenics were on haloperidol therapy at the time of MSP PET. The other two schizophrenics were treated with clozapine, in one of them MSP PET was carried out twice with different daily doses (100 mg and 450 mg respectively). Neuroleptic serum levels were measured in all patients. Results were compared with MSP PET of two drug-free male control subjects and with a previous fluoroethylspiperone (FESP) study of normals. Three hours after tracer injection specific binding of MSP was observed in the striatum in all cases. The striatum to cerebellum ratio was used to estimate the degree of neuroleptic-caused striatal D2 dopamine receptor occupancy. In the haloperidol treated patients MSP binding was significantly decreased, whereas in the clozapine treated patients striatum to cerebellum ratio was normal. Even the increase of clozapine dose in the same patient had no influence on this ratio. Despite the smaller number of patients the study shows for the first time in humans that striatal MSP binding reflects the different D2 dopamine receptor affinities of clozapine and haloperidol.
Collapse
Affiliation(s)
- H Karbe
- Universitätsklinik für Neurologie, Köln, Federal Republic of Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
50
|
Wienhard K, Herholz K, Coenen HH, Rudolf J, Kling P, Stöcklin G, Heiss WD. Increased amino acid transport into brain tumors measured by PET of L-(2-18F)fluorotyrosine. J Nucl Med 1991; 32:1338-46. [PMID: 1906093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The uptake of L-(2-18F)fluorotyrosine (F-Tyr), a newly synthetized amino acid tracer, was studied in 15 patients with various brain tumors by dynamic PET. The higher F-Tyr accumulation in tumors (mean 27% above contralateral tissue) was associated with two-fold transport rates into tumors, while the rate constants describing irreversible incorporation were decreased. The increased F-Tyr transport was not correlated to 68Ga-EDTA accumulation and cannot be explained by disruption of the blood-brain barrier. Kinetic analysis of 2-(18F)-fluoro-deoxy-glucose accumulation in the same patients demonstrated that increased metabolic rates in tumors are mainly caused by altered phosphorylation rates while transport of glucose is less affected. Since F-Tyr transport rates clearly separated tumors from normal tissue and since F-Tyr accumulation was related to tumor grade, PET studies of F-Tyr uptake are of clinical value for diagnosis and classification of brain tumors.
Collapse
Affiliation(s)
- K Wienhard
- Max-Planck-Institut für neurologische Forschung, Köln, Germany
| | | | | | | | | | | | | |
Collapse
|