Skin contamination by radiopharmaceuticals and decontamination strategies.

The aim of the present study was to evaluate the percutaneous penetration of five common radiopharmaceuticals ((99m)Tc, (67)Ga, (125)I, (111)In and (51)Cr) and to evaluate the effect of decontamination by a detergent solution dedicated to hospital institutions for that purpose. The skin kinetic profiles were established by using the in vitro Franz cell method over 24h. The skin distribution in each skin layer was quantified after 6h exposure time and the efficacy of the detergent solution to remove radionuclides was evaluated also after 6h. The most striking result was the repartition into two classes of kinetic profiles: (125)I and (99m)Tc permeated quickly (∼60% of applied activity after 24h) while the 3 other radionuclides permeated slowly (from ∼2.75% for (67)Ga to ∼10% of applied activity for (111)In). The lag times, i.e. the time necessary to cross the skin varied from 20min for (99m)Tc to 5h for (51)Cr, which accumulated in skin compartments. Skin washings with the detergent solution were particularly efficient for this radionuclide, contrary to the others for which the washing procedure should be applied earlier. The permeation of ions was dependent on their chemical and physical forms and on their salting-in or salting-out effects (coordination state and Hofmeister series).

[Aprepitant for the prevention of cisplatine induced nausea and vomiting: an observational study]. / Aprépitant pour la prévention des nausées et vomissements induits par une chimiothérapie à base de cisplatine: étude observationnelle.

Aprepitant is actually recommended in the prevention of nausea and vomiting induced by high emetic risk chemotherapy using cisplatin. We performed an observational prospective study on 101 patients evaluating the efficacy of aprepitant in the clinical conditions of use of cisplatin, out of context of clinical trial. We did not perform any intervention on the choice of anti-emetic treatment by the clinicians. Data on anti-emetic treatments were collected from prescriptions by a pharmacist after prior consultation with a medical doctor. Inclusions were closed when we lay 50 patients who received aprepitant associated to standard anti-emetic treatment (ondansetron and prednisolone) and 51 patients who received standard anti-emetic treatment. We observed a significant positive effect of aprepitant in the prevention of acute (84 vs 74.4 %, P = 0.24) and delayed vomiting (84 vs 60.8%, P = 0.009). But there was not a significant difference between the two groups regarding the prevention of nausea and the rate of complete response (absence of nausea and vomiting during five days).

The relation of putamen and caudate nucleus 18F-Dopa uptake to motor and cognitive performances in Parkinson's disease.

The contribution of striatal (caudate nucleus-putamen) dopaminergic deficiency to the severity of motor signs is well established in Parkinson's disease (PD), while its role in the occurrence of cognitive and mood changes remains unresolved. We therefore measured in 27 non-demented PD patients and 10 age-matched controls striatal uptake of [18F]-6-fluoro-L-Dopa (F-Dopa) with PET, and mood (Beck depression), memory (Grober-Buschke), frontal executive functions (verbal fluency and Wisconsin card sorting), and attentional processing of sensory stimuli (N2-P3 auditory event-related potentials--ERPs). Locomotor disability of patients was assessed by Hoehn and Yahr score and Unified Parkinson's Disease Rating Scale (UPDRS). ANOVA showed that memory, but neither frontal lobe functions nor ERPs, was significantly altered in PD patients, whereas indices of depression were found only in advanced PD. The F-Dopa rate constant Ki was significantly reduced in the striatum, more in putamen than caudate nucleus, and inversely correlated with disease duration. A significant inverse correlation was found between both putamen and caudate nucleus Ki and Hoehn and Yahr score, and between putamen--but not caudate nucleus Ki --and UPDRS motor score. Principal components analysis (PCA) of PD patients Ki values and mood, cognitive and ERP parameters gave a three-factor solution. Variables contributing to factor 1 were memory score and N2-P3 ERP latencies, those to factor 2 were striatal Ki values, and those to factor 3 frontal executive performances. Depression did not segregate with any variable. Our findings suggest that unlike locomotor disability, cognitive abilities and mood state of non-demented PD patients are for the most part unrelated to striatal dopaminergic depletion and may result from dysfunction of extra-striatal dopaminergic or from non-dopaminergic systems.

Paradoxical metabolic response of the human brain to a single electroconvulsive shock.

Regional brain protein synthesis was evaluated with positron emission tomography (PET) and L-(S-[11C]methyl)methionine ([11C]MET) in depressive patients, before and 3 h after an electroconvulsive shock (ECS), when energy supply is restored, and in healthy volunteers. Depressive patients presented apparent lower protein synthesis than normals, in agreement with known reduction of cerebral activity. In contrast, ECS resulted in a significant increase (56%, P < 0.05) in global cortical protein synthesis. This paradoxical hyperactivation of cellular protein metabolism in response to seizures and the fact that synaptic activity is further reduced after electroconvulsive therapy (ECT), may provide new insights for understanding the mechanism of action of ECT.

A controlled positron emission tomography study of obsessive and neutral auditory stimulation in obsessive-compulsive disorder with checking rituals.

Ten nondepressed patients with obsessive-compulsive disorder (OCD) who were characterized by predominant checking rituals were compared with 10 age- and sex-matched control subjects. Hemispheric and regional cerebral blood flow levels (rCBF) were measured with positron emission tomography (H2 15O) across four conditions: rest, auditory stimulation with idiosyncratic normal or abnormal obsession, auditory stimulation with neutral verbal stimuli, and rest. Order of neutral and obsessive stimulation was randomized. Higher subjective responses to obsessive than to neutral stimulation were found in both groups; subjective response was higher in OCD patients when obsessive stimulation was presented first. A four-way analysis of variance (group x stimulation order x hemisphere x condition [neutral or obsessive stimulation]) was performed on stimulation minus rest normalized rCBF values. Control subjects had significantly higher rCBF in the thalamus and putamen. A trend toward higher rCBF in OCD patients was found in the superior temporal regions. When neutral stimulation was presented first, rCBF was significantly higher in the caudate region of control subjects. Obsessive stimulation was associated with higher rCBF than neutral stimulation in orbitofrontal regions in both groups of subjects. Under obsessive stimulation, superior temporal and orbitofrontal activities were correlated in OCD patients but not in control subjects. Our study suggests specific abnormalities of information processing in the basal ganglia and temporal structures of compulsive checkers.

Effects of GABAA receptors activation on brain glucose metabolism in normal subjects and temporal lobe epilepsy (TLE) patients. A positron emission tomography (PET) study. Part I: Brain glucose metabolism is increased after GABAA receptors activation.

Though gamma-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the human central nervous system, the metabolic response to GABA system activation remains imperfectly known. We studied in vivo with positron emission tomography (PET) the variations of glucose metabolism in the human brain after stimulation of the GABAA receptors by systemic administration of the specific GABAA agonist, 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP). These investigations were performed in three normal volunteers and as part of presurgical evaluation for temporal lobe epilepsy in six patients. While clinical and electroencephalographic (EEG) monitoring showed a sedative effect and sleepiness after THIP administration, glucose metabolism was paradoxically increased in grey matter structures, which are known to have a high density of GABAA receptors. These findings suggest that the pharmacological activation of GABA pathways, although inhibitory and producing a decrease of vigilance, increases the energetic demand at least during a phase of GABA agonist action, probably at the synaptic or at the glial cell level.

Effects of GABAA receptors activation on brain glucose metabolism in normal subjects and temporal lobe epilepsy (TLE) patients. A positron emission tomography (PET) study. Part II: The focal hypometabolism is reactive to GABAA agonist administration in TLE.

Positron emission tomography (PET) using [18F]fluorodeoxyglucose (FDG) was used to study the metabolic response of focal hypometabolism to the administration of a specific GABAA agonist (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol), THIP, in six temporal lobe epilepsy (TLE) patients. After THIP injection, the increase of glucose metabolism in the hypometabolic focus was larger than the mean increase reported in the whole brain (Part I; Epilepsy Res., 19 (1994) 45-54). Within the hypometabolic focus, this increase was significantly higher in regions with the lowest basal metabolic level. This metabolic response in the hypometabolic focus, observed in the absence of any epileptic discharge during FDG accumulation and PET data acquisition, suggests that GABAA receptors are up-regulated or, at least, preserved in TLE.

Relief of akinesia by apomorphine and cerebral metabolic changes in Parkinson's disease.

The cerebral metabolic rate of glucose was measured in 14 Parkinson's disease patients with severe on-off fluctuations. Two positron emission tomography (PET) scans with [18F]fluorodeoxyglucose were performed, one after a challenge of subcutaneous apomorphine at a dose able to relieve akinesia within 15 min and the other with the vehicle. Apomorphine reduced glucose utilization by 4-6% in the lenticular nuclei and the occipital cortex and by 6-9% in the thalamic nuclei, but this effect was not statistically significant. Thus, central stimulation of dopamine receptors by apomorphine in advanced Parkinson's disease is not associated with cerebral metabolic changes as assessed by PET. Despite a dramatic improvement of the motor state, the global neuronal activity in the striatum and its downstream projections remains stable, suggesting an equilibrium between excitatory and inhibitory dopaminergic activities.

Metabolic patterns associated with non-specific magnetic resonance imaging abnormalities in temporal lobe epilepsy.

We investigated the cerebral metabolic patterns associated with non-specific hyperintense T2-weighted image on Magnetic Resonance Imaging (MRI) in Temporal Lobe Epilepsy (TLE). Nineteen patients suffering from TLE with a normal CT scan underwent Positron Emission Tomography (PET) using 18F-fluorodeoxyglucose; 8 had hyperintense T2-weighted image on MRI in the epileptogenic temporal lobe and 11 had a normal MRI. Interictally, PET exhibited focal hypometabolism in all the patients with hyperintense T2-weighted image and in 8 of the 11 whose MRI was normal. The hypometabolic area was significantly more extensive in patients with hyperintense T2-weighted image in whom it always encompasses the site of the MRI abnormality. Moreover, these patients had higher metabolic asymmetry index in the temporal and parietal lobes than patients with a normal MRI. One patient with mesial temporal hyperintense T2-weighted image underwent an ictal PET, which showed that the focal hypermetabolism fitted remarkably with the site and size of the abnormal MR signal. Thus, non-specific hyperintense T2-weighted images are associated with particular interictal and ictal metabolic patterns which might suggest that these MRI abnormalities reflect an epileptogenic lesion.

Pharmacokinetics of melatonin in man after intravenous infusion and bolus injection.

The pharmacokinetics of melatonin during the day-time has been studied in 4 healthy subjects after a bolus i.v. injection of 5 or 10 micrograms/person and after a 5 h infusion of 20 micrograms per person in 6 healthy subjects. In addition, a pinealomectomized patient whose nocturnal plasma melatonin had been abolished was investigated after the i.v. infusion--once during the night and once during the day. The clearance of melatonin from blood showed a biexponential decay. The pharmacokinetic parameters in the two studies were similar, except for the disappearance rate constant beta and the apparent volume of distribution at steady-state (Vss). Supplementary peaks or troughs were superimposed on the plateau and the falling part of the profile. They were not due to stimulation of endogenous secretion, because they were also seen in the pinealomectomized patient. During the melatonin infusion, the plasma hormone level reached a steady-state after 60 and 120 min, and when it was equal to the nocturnal level. The infusion regime may be valuable in replacing blunted hormonal secretion in disease states.

Serum copper and zinc concentration in premature and small-for-date infants.

Serum copper (Cu) and zinc (Zn) concentrations were measured in neonates with an appropriate birth weight for gestational age (AGA) and in small-for-gestational age infants. At 7 days of age, there was a positive correlation between serum Cu concentration and gestational age (GA) (r = 0.63; P < 0.001) and a negative correlation between Zn concentration and GA (r = 0.62; P < 0.01). At 7 days of age, the mean (+/- S.E.) concentrations in AGA full-term infants (Cu, 79 +/- 8 microgram/dl; Zn, 84 +/- 4) were similar to those in small-for-gestational age, full-term infants (Cu, 78 +/- 6 microgram/dl; Zn, 85 +/- 12). In preterm infants, there was also no difference between AGA and small-for-gestational age infants. In 23 AGA infants with a birth weight of less than 1500 g, serum Cu concentration increased from 51 +/- 7 microgram/dl at the age of 7 days to 86 +/- 7 microgram/dl at the age of 60 days (paired t-test: P < 0.05) whereas serum Zn concentration decreased from 149 +/- 9 to 91 +/- 5 microgram/dl (P < 0.01). A positive correlation was found between serum Zn concentration and daily intake of Zn (n = 39; r = 0.3458; P < 0.05), but no correlation was found for serum Cu concentration. The evolution of serum Cu and Zn concentration with total age (GA + postnatal age) in the infants with a low birth weight (i.e., < 1500 g) was similar to the evolution with GA.

Bone kinetics of calcium-45 and pyrophosphate labeled with technetium-96: an autoradiographic evaluation.

The uptake of calcium-45 and of pyrophosphate labeled with the long-lived technetium-96 isotope were compared by means of liquid-emulsion microautoradiograms of the epiphyseal plates of 10-week-old rabbits, at 30 min, and 3 and 48 hr after i.v. administration. For both tracers, thin sections confirm the significant role of the blood supply, especially shortly after injection. However, other more specific mechanisms lead to a mixing of the calcium in the mineral mass and to a linear deposition of technetium facing the osteoid surfaces. These findings suggest that the tropism of tin-reduced technetium pyrophosphate is not governed by the mineral pool but rather by exchanges inside a still poorly calcified organic matrix.

Skeletal uptake of pyrophosphate labeled with technetium-95m and technetium-96, as evaluated by autoradiography.

For animal experimentation, the 95m and 96 technetium isotopes offer many advantages over technetium-99m. Their long physical half-lives and the emission of extranuclear electrons of low penetrating power make it possible to obtain autoradiograms of a great precision. The uptake of technetium stannous pyrophosphate by the epiphyseal plate was studied using liquid-emulsion microautoradiography, 3 hr after i.v. injection into 10-week-old rabbits. Microautoradiograms showed a well-defined and rather specific pattern of localization with intense uptake beneath the epiphyseal disk on the extremities of the vascular buds and a lack of accumulation in the cartilage, whether calcified or uncalcified. In the metaphysis, the label was located where new bone was being laid down and also over the cytoplasm of osteoclasts. We deduce from these results that in normal bone the general distribution of this tracer reflects mainly the arrangement of the blood supply, but the specific sites of accumulation are the bone-forming surfaces and the active resorbing osteoclasts.

Copper deficiency and hypocalcemic rickets in a small-for-date infant.

A case of copper deficiency associated with hypocalcemia, radiological features of rickets and hyperparathyroidism is described in a small-for-date infant (gestational age 39 weeks, B.W 1 240 g). Neonatal serum copper (Cu) levels were found between 223 and 138 mumol/l. She was given daily 2 400 U of vitamin D2 and a load dose of 80 000 IU at the age of 55 days. At the age of 79 days, X-rays of the legs and wrist showed spread, cupped and frayed metaphyses. Serum Ca was 1.35 mmol/l, P = 0.99 mmol/l with high alkaline phosphatases (A.P.) 590 IU/ml. But plasma level of 25 hydroxycholecalciferol (25-OH-CC) was normal = 10.8 ng/ml. Serum Cu was low = 3.14 mumol/l and serum immunoreactive parathormone (iPTH) level was elevated: 520 mulEq/ml (N less than or equal to 100). Administration of vitamin D2 (15 mg) induced an immediate normalization of serum Ca, normal serum iPTH (68 mulEq/ml) in one month, normal X-rays in two months and normal A.P. in four months. Serum Cu and ceruloplasmin levels increased slowly without any supplementation to subnormal levels at the age of eight months (14.9 and 1.65 mumol/l. Serum Cu concentrations were found to be normal (16.0--33.7 mumol/l) in five children with hypocalcemic rickets. These results suggest a role of Cu deficiency in the occurrence of this transient vitamin D-resistant rickets.

[A case of Nonne-Milroy syndrome associated with chyloabdomen. Immunologic study]. / Un caso de síndrome de None Milroy asociado a quiloabdomen. Estudio inmunológico

A case of None Milroy syndrome with chiloabdomen in a 7 year old girl is reported. The most important features are the immunological alterations (depressed delayed immunity in the affected extremity and decreased level of IgA). A review of the literature is made.