PubMed HealthSearch

Biomedical subjects

M J De Roo

Publications and source records attributed to M J De Roo.

5 recordsLinked to original sources

Evaluation of the renal excretion characteristics of technetium-99m mercaptoacetylglycyl-D-alanylglycine in healthy volunteers.

During a study of C-methyl derivatives of technetium-99m mercaptoacetyltriglycine (99mTc-MAG3) it was found that the isomer of 99mTc-mercaptoacetylglycyl-D-alanylglycine (99m-TC-MAGAG-DA) is superior to 99mTc-MAG3 with regard to its renal excretion characteristics in both mice and the baboon. We have now compared the renal handling of 99mTc-MAGAG-DA and 99mTc-MAG3 in 6 healthy volunteers in a paired study. Renograms of 99mTc-MAGAG-DA show a shorter time to renal maximum and a lower residual renal activity at 30 min post-injection (p.i.). The urinary excretion of 99mTc-MAGAG-DA is higher at both 30 and 60 min p.i. The plasma concentration of 99mTc-MAGAG-DA is lower than that of 99mTc-MAG3 at each moment up to 60 min p.i., and the plasma clearance is accordingly higher. It is concluded that 99mTc-MAGAG-DA is excreted more efficiently than 99mTc-MAG3, but the preparation of 99mTc-MAGAG-DA requires a HPLC purification step, and this limits its practical clinical usefulness.

Adult

Technetium-99m-L,L-ethylenedicysteine: a renal imaging agent. I. Labeling and evaluation in animals.

L,L-ethylenedicysteine (L,L-EC) can be labeled efficiently with 99mTc at pH 12 to obtain a highly pure and very stable tracer agent (99mTc-L,L-EC). The biological behavior of 99mTc-L,L-EC was studied in mice and a baboon. In mice, 99mTc-L,L-EC demonstrated a more rapid urinary excretion and less retention in the kidneys, the liver, the intestines, and the blood than did 99mTc-MAG3 at 10 and 60 min p.i. Urinary excretion decreased in probenecid pretreated mice, which indicates active tubular transport. In the baboon, the renograms for 99mTc-MAG3 and 99mTc-L,L-EC were comparable. Plasma-protein binding of 99mTc-L,L-EC was lower than that of 99mTc-MAG3 while its distribution volume and 1-hr plasma clearance were clearly higher. The promising results of the animal experiments suggest that 99mTc-L,L-ethylenedicysteine may be a useful alternative to 99mTc-MAG3 for renal function studies in humans.

Animals

Critical appraisal of angioscintigraphy as a diagnostic procedure in cerebrovascular disease.

In order to assess the diagnostic usefulness of combined functional and morphological isotopic investigations of brain vascularization after intravenous injection of a bolus 99mTc pertechnetate, the authors explored, besides a control group, patients with acute cerebrovascular disease, angiomas, aneurysms and intracerebral hematomas. Combined flow evaluation and visualization of the intracerebral bolus transit was highly effective in patients with cerebrovascular disease. Angiomas with a diameter of 2 cm or more are always visible, the abnormal vascularization of the affected hemisphere being correctly evaluated. Cerebral aneurysms are frequently missed by angioscintigraphy. Intracerebral hematoma generally gives false negative results.

Adult