UNLABELLED Rheumatoid arthritis (RA) involves the accumulation of monocyte-derived macrophages in the affected synovial tissue. This process of cell migration could be portrayed scintigraphically to monitor noninvasively the effects of therapy on the progress of the disease. For this purpose, labeling of purified autologous monocytes with 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) at ve...

UNLABELLED SPECT using 99mTc-hexamethyl propyleneamine oxime (HMPAO) mainly reflects regional cerebral blood flow, however metabolic abnormalities also affect the retention of 99mTc-HMPAO. METHODS To rule out any flow factor, a test-tube model was used to evaluate the effects of metabolic alterations both on intracellular trapping of 99mTc-HMPAO and on extracellular glutamate and lactate dehy...

The sensitivity of technetium-99m- (99mTc) d,l-HMPAO to radiolytically induced dissociation in aqueous solutions was investigated. It was found that cobalt-60 (60Co) gamma irradiation of solutions containing 99mTc-d,l-HMPAO with only 1600 cGy reduced the lipophilic chelates' radiochemical purity (RCP) to 50%-60%. The radiolytic sensitivity of 99mTc-meso-HMPAO is significantly lower. The results...

BACKGROUND AND PURPOSE The brain distribution of 9mTc-hexamethylpropyleneamine oxime (HMPAO) correlates with regional brain perfusion, whereas 99mTc-ethyl cysteinate dimer (ECD) reflects not only perfusion but also the metabolic status of brain tissue. We compared 99mTc-ECD single-photon emission CT (SPECT) with 99mTc-HMPAO SPECT early after recanalization by local intraarterial thrombolysis (L...

UNLABELLED To visualize the regional localization of glutathione (GSH) in the brain, the relationship between the concentrations of tissue GSH and uptake of [99mTc]meso-hexamethyl propyleneamine oxime ([99mTc] meso-HMPAO) or [99mTc]d,l-hexamethyl propyleneamine oxime ([99mTc]d,l-HMPAO) was studied in mice. METHODS The uptake of [99mTc]meso-HMPAO in the mouse brain was decreased to 35% of cont...

The ideal imaging method in inflammatory bowel disease would reliably detect inflammation, identify the correct intestinal location, and assess the severity of the disease. The aim of this study was to compare scintigraphic methods of quantifying overall disease activity using both indium-111 (111In) and technetium-99M (99mTc) HMPAO labelled leucocyte scans. The four day faecal excretion of 111...

in recent years, several radiopharmaceuticals have been developed for imaging regional cerebral blood flow (rcbf) such as 75se labelled pipse and mose, ²º¹ti labelled ddc and 99mtc labelled hmpao. hmpao with two asymmetric carbon atoms (at the 3 and 9 positions), produces d,1 and meso isomers, only one of which is retained in the brain. rapid intracellular conversion of 99mtc-d,1-hmpao to hydro...

In recent years, several radiopharmaceuticals have been developed for imaging regional cerebral blood flow (rCBF) such as 75Se labelled PIPSE and MOSE, ²º¹TI labelled DDC and 99mTc labelled HMPAO. HMPAO with two asymmetric carbon atoms (At the 3 and 9 positions), produces d,1 and meso isomers, only one of which is retained in the brain. Rapid intracellular conversion of 99mTc-d,1-HMPAO to...

99mTc complex of hexamethylpropylene amine oxime (99mTc-HMPAO), which has been used as a tracer for regional cerebral blood flow (rCBF), has been shown to localize in primary brain tumors with wide spectrum of its uptake. The causes of the wide spectrum of tumor uptake, however, has not been understood in detail. We performed autoradiographic study with this agent to get further knowledge about...

Background The ability to follow the distribution and migration of biologically active cells in human is essential for the development of cell-based therapies and diagnostics. Nuclear medicine imaging is widely applied in clinic as an attractive technique for in vivo WBC and stem cell tracking. The aim of this study was to evaluate prosthesis infection of a 51 years old man with previous histo...