Publications by authors named "Patrizia Riccardi"

Background: Attention deficit hyperactivity disorder (ADHD) is one of the most common psychiatric disorders, affecting an estimated 5 to 12% of school-aged children worldwide. From 15 to 19 million Chinese children suffer from ADHD. The aim of this study was to investigate the association between family-environmental factors and ADHD in a sample of Chinese children.

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The purpose of this study was to examine sex differences in the correlations of d-amphetamine (d-AMPH) induced displacements of [¹⁸F]fallypride in striatal and extrastriatal regions in relation to affect and cognition. Seven male and six female healthy subjects, whose mean age was 25.9 years, underwent positron emission tomography (PET) with [¹⁸F]fallypride at baseline and 3 h after a 0.

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Individual differences in dopamine D2-like receptor availability arise across all brain regions expressing D2-like receptors. However, the interrelationships in receptor availability across brain regions are poorly understood. To address this issue, we examined the relationship between D2-like binding potential (BPND) across striatal and extrastriatal regions in a sample of healthy participants.

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The relationship between cerebral morphology and the expression of dopamine receptors has not been extensively studied in humans. Elucidation of such relationships may have important methodological implications for clinical studies of dopamine receptor ligand binding differences between control and patient groups. The association between cerebral morphology and dopamine receptor distribution was examined in 45 healthy subjects who completed T1-weighted structural MRI and PET scanning with the D(2)/D(3) ligand [(18)F]fallypride.

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Background: Studies in schizophrenic patients have reported dopaminergic abnormalities in striatum, substantia nigra, thalamus, anterior cingulate, hippocampus, and cortex that have been related to positive symptoms and cognitive impairments.

Methods: [(18)F]fallypride positron emission tomography studies were performed in off-medication or never-medicated schizophrenic subjects (n = 11, 6 men, 5 women; mean age of 30.5 +/- 8.

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Novelty-seeking personality traits are a major risk factor for the development of drug abuse and other unsafe behaviors. Rodent models of temperament indicate that high novelty responding is associated with decreased inhibitory autoreceptor control of midbrain dopamine neurons. It has been speculated that individual differences in dopamine functioning also underlie the personality trait of novelty seeking in humans.

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Background: This study examined whether positron emission tomography (PET) studies with [18F] fallypride performed before and after alpha-methyl-para-tyrosine (AMPT) administration can be used to estimate baseline dopamine (DA) D2 receptor occupancy in striatal and extrastriatal regions.

Methods: Six normal subjects underwent PET with [18 F] fallypride before and after administration of AMPT. The DA D2 receptor binding potentials (bp) were calculated with the reference region method.

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New guidelines suggest that HIV-infected pregnant women should be offered combination antiretroviral therapy (zidovudine and protease inhibitors) to prevent fetal HIV infection but concerns remain about potential adverse effects for the infant. Prior small case series have suggested an increased risk for hemangioma. In this study we used zidovudine and indinavir, alone or in combination, to assess the effect on an in vitro angiogenesis system for endothelial cells.

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Objective: The authors examined gender differences in d-amphetamine-induced displacements of [(18)F]fallypride in the striatal and extrastriatal brain regions and the correlations of these displacements with cognition and sensation seeking.

Method: Six women and seven men underwent positron emission tomography (PET) with [(18)F]fallypride before and after an oral dose of d-amphetamine. Percent displacements were calculated using regions of interest and parametric images of dopamine 2 (D(2)) receptor binding potential.

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Objective: A non-invasive prenatal determination of the fetal RhD status might be useful for the management of pregnancies in RhD-negative women whose partners are RhD positive.

Methods: Maternal peripheral blood of 32 RhD-negative women (17-24 weeks of gestation) was collected, and circulating fetal cells were enriched by CD71 mini-magnetic activated cell sorting. The RhD status of the fetuses was assessed using multiparametric flow cytometry, and results were compared to those of reverse transcriptase (RT)-polymerase chain reaction (PCR), or PCR, which acted as control.

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Clozapine and quetiapine have a low incidence of extrapyramidal side effects at clinically effective doses, which appears to be related to their significantly lower occupancy of striatal dopamine D2 receptors (DA D2r) compared to typical antipsychotic drugs (APDs). Animal studies have indicated that clozapine and quetiapine produce selective effects on cortical and limbic regions of the brain and in particular on dopaminergic neurotransmission in these regions. Previous PET and SPECT studies have reported conflicting results regarding whether clozapine produces preferential occupancy of cortical DA D2r.

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This study examined D-amphetamine (D-AMPH)-induced displacements of [18F] fallypride in striatal and extrastriatal regions and the correlations of these displacements with cognition, affect, and sensation-seeking behavior. In all, 14 normal subjects, six females and eight males (ages 21-32, mean age 25.9 years), underwent positron emission tomography (PET) with [18F]fallypride before and 3 h after a 0.

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Unlabelled: (123)I-5-IA-85380 ((123)I-5-IA; [(123)I]-5-iodo-3-[2(S)-azetidinylmethoxy]pyridine) is a promising SPECT radiotracer for imaging beta(2)-containing nicotinic acetylcholine receptors (beta(2)-nAChRs) in brain. Beta(2)-nAChRs are the initial site of action of nicotine and are implicated in various neuropsychiatric disorders. The feasibility and reproducibility of the bolus-plus-constant-infusion paradigm for equilibrium modeling of (123)I-5-IA using SPECT in healthy nonsmokers was studied.

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There have been conflicting reports as to whether olanzapine produces lower occupancy of striatal dopamine D(2)/D(3) receptor than typical antipsychotic drugs and preferential occupancy of extrastriatal dopamine D(2)/D(3) receptors. We performed [(18)F] fallypride PET studies in six schizophrenic subjects treated with olanzapine and six schizophrenic subjects treated with haloperidol to examine the occupancy of striatal and extrastriatal dopamine receptors by these antipsychotic drugs. [(18)F] setoperone PET studies were performed in seven olanzapine-treated subjects to determine 5-HT(2A) receptor occupancy.

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Hyperhomocysteinemia has been suggested as a possible risk factor in women suffering from habitual abortions, placental abruption or infarcts, preeclampsia, and/or intrauterine growth retardation. However, little is known about the pathogenic mechanisms underlying the action of homocysteine. The present study investigated the in vitro ability of homocysteine to affect trophoblast gonadotropin secretion and to induce cell death.

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