The importance of the unsuppressed glands in the study of intact parathyroid hormone disappearance after parathyroid adenomectomy.

Background: In the usual techniques for intraoperative intact parathyroid hormone (iPTH) monitoring for primary hyperparathyroidism, the normal glands are implicitly considered suppressed. On the contrary, we believe, as do other researchers, that they are not totally suppressed.

Methods: For this reason, we considered the introduction of an infusion from the unsuppressed normal glands (UNG), described by an influx constant (IC (pg/ml per min)), into the formulation of a two-compartment model.

Use of technetium-99m hexamethylpropylene amine oxime SPET for the study of cerebral blood flow reactivity after acetazolamide infusion in patients with Behçet's disease.

The purpose of this study was to characterise the nature of the baseline perfusion defects found in patients with Behçet's disease using hexamethylpropylene amine oxime single-photon emission tomography in conjunction with acetazolamide test (Acz SPET). Eleven patients underwent both baseline and Acz SPET. Regions of interest (ROIs) were drawn on the areas with decreased perfusion (D-ROI) and, in the same section, on areas with normal perfusion (N-ROI).

Excessive vasoconstriction after stress by the aging kidney: inadequate prostaglandin modulation of increased endothelin activity.

The adaptive capacity of the aging kidney to stimulation of the sympathetic nervous system, as induced by a 30-minute mental stress (MS), was assessed in 8 elderly healthy women (68 to 82 years of age) and compared with that of 8 younger women (24 to 40 years of age). The study encompassed 4 consecutive 30-minute periods (baseline, mental stress, recovery 1, and recovery 2). In the elderly subjects, baseline effective renal plasma flow (ERPF)(iodine 131-labeled hippurate clearance) was lower and glomerular filtration rate (GFR)(iodine 125-labeled iothalamate clearance) was proportionally less reduced than in the younger group; the filtration fraction (FF) was higher.

First-pass cerebral extraction of benzamide-derivative radiotracers for SPECT.

Central dopaminergic receptors are widely studied for their importance in the pathophysiology of neurological and psychiatric diseases. We have investigated the cerebral delivery kinetics of three dopaminergic ligands in rats through the use of an indicator fractionation method to measure the tracer's regional influx rate constant with respect to regional blood flow. The aim is to collect the in vivo kinetic parameters of the radioligand cerebral distribution, which are necessary if, dealing with SPECT and "trapped" tracers, one wishes to analyse data using a graphical approach.

Regional cerebral blood flow in juvenile systemic lupus erythematosus: a prospective SPECT study. Single photon emission computed tomography.

Objective: Using single photon emission computed tomography (SPECT) we evaluated the presence and evolution of changes in brain perfusion in juvenile systemic lupus erythematosus (JSLE).

Methods: SPECT was performed in 14 patients with active JSLE divided in 2 groups: the first included 7 patients without central nervous system (CNS) involvement and the second 7 patients with minor neuropsychiatric symptoms (headache, reactive depression, cognitive impairment, mood swing). SPECT findings were compared to seroimmunological and magnetic resonance imaging (MRI) data.