In vivo biodistribution of 125IPIP and internal dosimetry of 123IPIP radioiodinated agents selective to the muscarinic acetylcholinergic receptor complex

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/134943/1/mp8941.pd

Re-HEDP : pharmacokinetic characterization, clinical and dosimetric evaluation in osseous metastatic patients with two levels of radiopharmaceutical dose

BACKGROUND: A study for pain relief therapy with (188)Re-HEDP was done in patients with bone metastases secondary to breast and prostate cancer. MATERIALS AND METHODS: Patients received 1.3 or 2.2 GBq, in single or multiple doses. Platelets, white and red cells were evaluated during 11 weeks. Pharmacokinetic characterization was done from blood and urine samples for 5 patients along 24 hours. Urinary excretion was evaluated in other 16 patients during 6 hours. Bone uptake was estimated as remaining activity in whole body. Scintigraphic images were acquired at 2 and 24 hs post-administration. Absorbed dose in bone marrow was estimated with Mirdose3. Analgesics intake and pain score were daily recorded. Tumour markers (PSA, and Tn-structure) were monitored in 9 patients during 4 to 6 months. Single doses of low activity (1.3 GBq) were given to twelve patients. Nine patients received multiple doses. RESULTS: All except one patient had normal levels of platelets, white and red cells. Remaining dose in blood at 2 hours was 9%. Urinary elimination was 58%. Bone uptake at 24 hours was 43% (mean value; n = 5). No changes of the haematological parameters were detected along follow-up period. Pain relief was evidenced by decrease or supression of opioid analgesic and by subjective index. PSA showed a decrease in prostate cancer patients (n = 4). Tn-structure showed a significant increase after 4 to 8 months. CONCLUSION: Single or multiple dose scheme could be safely used, with administered activity of (188)Re-HEDP up to 60 mCi, with low bone marrow absorbed doses

Efficient microscale preparation of tin-117m-tin tetrachloride-a pivotal intermediate for the synthesis of tin-117m-labeled radiopharmaceuticals

A microscale technique has been developed for the preparation of /sup 117m/SnCl/sub 4/. The radiolabeled tin tetrachloride is an important intermediate for the synthesis of /sup 117m/Sn-labeled organic radiopharmaceuticals. The flow-through system involves high temperature chlorination of metallic /sup 117m/Sn with subsequent cryogenic collection of the /sup 117m/SnCl/sub 4/ in a special reaction vessel. This vessel can then be used for the conversion of the tin tetrachloride to various useful intermediates. The reactions that have been studied include the formation of tetraalkyl and tetraaryltin compounds by reaction of SnCl/sub 4/ with Grignard or alkyl and aryl lithium reagents (SnCl/sub 4/ ..-->.. R/sub 4/Sn or Ar/sub 4/Sn). In addition, by stoichiometric control, the comproportionation of SnCl/sub 4/ with tetramethyltin can yield any one of the mixed methylchlorotin intermediates, MeSnCl/sub 3/, Me/sub 2/SnCl/sub 2/, or Me/sub 3/SnCl. These products are important intermediates for the preparation of /sup 117m/Sn-labeled steroids, fatty acids, amino acids, barbituates, and a variety of other potentially useful agents

Tellurium-123m-labeled isosteres of palmitoleic and oleic acids show high myocardial uptake

These studies were directed at determining if the telluro fatty acids prepared by the isosteric replacement of the ..delta../sup 9/-double bonds of oleic and palmitoleic acids with /sup 123m/Te would show heart uptake in rats. The isostere of palmitoleic acid, 9-tellurapentadecanoic acid(II), was prepared by basic hydrolysis of the product formed by the coupling of /sup 123m/Te-sodium hexyl tellurol with methyl-8-bromooctadecanoate. Similarly, the isostere of oleic acid, 9-telluraheptadecanoic acid(IV), was prepared by the same route beginning with the reaction of /sup 123m/Te-sodium octyl tellurol with methyl-8-bromooctadecanoate. Both /sup 123m/Te-(II) and /sup 123m/Te-(IV) showed remarkably high heart uptake in rats (2 to 3% dose/gm) ten minutes after intravenous administration, and the heart/blood ratios were high (20-30/1). Finally, the hearts of rats injected with /sup 123m/Te-(IV) have been clearly imaged with a rectilinear scanner

125I-BMIPP and 18F-FDG uptake in a transgenic mouse model of stunned myocardium

Reported metabolic patterns in myocardial stunning are not uniform. We investigated relative myocardial perfusion, glucose and fatty acid uptake using a technetium-99 hexakis-2-methoxyisobutyl-isonitrile (MIBI), fluorine-18 2-fluoro-2-deoxyglucose (FDG) and iodine-125 15-(p-iodo-phenyl)-3(R,S)-methylpentadecanoic acid (BMIPP) mixture, in a recently developed transgenic (TR) mouse model which mimics stunned myocardium. Twenty-seven mice - 14 TR and 13 age-matched wild type controls (C) - were divided into four groups: TR-fed, TR-fasted, C-fed and C-fasted. Animals were sacrificed 2 h after injection, tissue samples counted and percent-injected dose/gram tissue (% id/g) calculated for each radioisotope. Tissues were also Folch extracted and 125I incorporation into the various lipid pools (TG, triglycerides; DG, diglycerides; FFA, free fatty acids; PL, phospholipids) was determined by thin-layer chromatography (TLC). The pooled data for each of the four groups (TR-fed vs C-fed and TR-fed vs C-fasted) showed no differences in myocardial blood flow (% MIBI id/g), glucose uptake (% FDG id/g) or fatty acid uptake (% BMIPP id/g). Only minor differences were observed in the incorporation of 125I-BMIPP into the myocardial TG, DG, FFA and PL lipid pools. However, significantly decreased myocardial FDG uptake was observed in a subset of fasted mice - four out of ten TR-fasted mice (3.4% vs 20.5% id/g) and three out of nine C-fasted mice (5.5% vs 30.6% id/g). The transgenic mouse model of stunned myocardium shows normal myocardial perfusion and overall intact myocardial glucose and myocardial fatty acid uptake as determined with clinically applicable radiolabelled analogues. These data are in line with the hypothesis that the contractile inefficiency in stunned myocardium is not linked to metabolic alterations but is associated with an insufficient chemical to mechanical energy couplin