Search results for "Positron"

Bone metastasis of a breast cancer detected by 3'-deoxy-3'-18F-fluorothymidine PET/CT

2008

International audience

SPECT Bone scintigraphy of benign and malignant lesions of the spine

1989

70 patients were examined with planar and SPECT bone scintigraphy. SPECT proved to be superior over planar bone scanning for imaging of traumatic, inflammatory, and malignant bone lesions. SPECT provides three-dimensional information and, therefore, delineates the exact location and extension of lesions. It also has a higher sensitivity than planar bone scintigraphy. The three-dimensional bone scan generates complementary diagnostic information which often facilitates an adequate therapy protocol.

Sympathetic activity at rest and motor brain areas: FDG-PET study.

2008

Although recent studies identified brain areas which are involved in short term activation of the sympathetic nervous system, little is known about brain mechanisms which generate the individual variability of basal autonomic activity. In this fluorodeoxyglucose positron emission tomography study (FDG-PET), we aimed to identify brain regions, which covary with function parameters of the autonomic nervous system at rest. Therefore, FDG-PET (Siemens, Germany) was performed twice in 14 healthy resting subjects (7 m, 7 f; mean age 29.5 years) while different parameters of autonomic function were assessed simultaneously: Blood pressure, heart rate, power spectra of heart rate variability (HF/LF …

Gaussian Mixture Models and Model Selection for [18F] Fluorodeoxyglucose Positron Emission Tomography Classification in Alzheimer’s Disease

2015

We present a method to discover discriminative brain metabolism patterns in [18F] fluorodeoxyglucose positron emission tomography (PET) scans, facilitating the clinical diagnosis of Alzheimer's disease. In the work, the term "pattern" stands for a certain brain region that characterizes a target group of patients and can be used for a classification as well as interpretation purposes. Thus, it can be understood as a so-called "region of interest (ROI)". In the literature, an ROI is often found by a given brain atlas that defines a number of brain regions, which corresponds to an anatomical approach. The present work introduces a semi-data-driven approach that is based on learning the charac…

Prosthetic joint infection caused by Mycobacterium avium complex.

2019

Immunological and immunogenetic markers in sporadic Alzheimer’s disease

2006

Background: Common polymorphisms of genes controlling inflammation-modulating cytokines and acute-phase proteins which play important roles in the pathogenesis of Alzheimer''s disease (AD) have been shown to be associated with AD. Aims: The immunological and immunogenetic markers potentially useful for the AD risk evaluation and diagnosis are briefly reviewed. Conclusion: The state-of-the-art of immunological and immunogenetic markers of AD indicates that new tools and strategies are necessary to identify gene products useful as diagnostic tools.

Opiate-induced dopamine release is modulated by severity of alcohol dependence: an [(18)F]fallypride positron emission tomography study.

2011

Background Preclinical data implicate the reinforcing effects of alcohol to be mediated by interaction between the opioid and dopamine systems of the brain. Specifically, alcohol-induced release of β-endorphins stimulates μ-opioid receptors (MORs), which is believed to cause dopamine release in the brain reward system. Individual differences in opioid or dopamine neurotransmission have been suggested to be responsible for enhanced liability to abuse alcohol. In the present study, a single dose of the MOR agonist remifentanil was administered in detoxified alcohol-dependent patients and healthy control subjects to mimic the β-endorphin-releasing properties of ethanol and to assess the effect…

Synthesis and evaluation of zirconium-89 labelled and long-lived GLP-1 receptor agonists for PET imaging

2020

Contains fulltext : 220838.pdf (Publisher’s version ) (Open Access) INTRODUCTION: Lately, zirconium-89 has shown great promise as a radionuclide for PET applications of long circulating biomolecules. Here, the design and synthesis of protracted and long-lived GLP-1 receptor agonists conjugated to desferrioxamine and labelled with zirconium-89 is presented with the purpose of studying their in vivo distribution by PET imaging. The labelled conjugates were evaluated and compared to a non-labelled GLP-1 receptor agonist in both in vitro and in vivo assays to certify that the modification did not significantly alter the peptides' structure or function. Finally, the zirconium-89 labelled peptide…

Synthesis and Characterization of a Novel Series of Agonist Compounds as Potential Radiopharmaceuticals for Imaging Dopamine D-2/3 Receptors in Their…

2014

Imaging of dopamine D2/3 receptors (D2/3R) can shed light on the nature of several neuropsychiatric disorders in which dysregulation of D2/3R signaling is involved. Agonist D2/3 tracers for PET/SPECT imaging are considered to be superior to antagonists because they are more sensitive to dopamine concentrations and may selectively label the high-affinity receptor state. Carbon-11-labeled D2/3R agonists have been developed, but these short-lived tracers can be used only in centers with a cyclotron. Here, we report the development of a series of novel D2R agonist compounds based on the 2-aminomethylchromane (AMC) scaffold that provides ample opportunities for the introduction of longer-lived […

Die nächste Generation „atypischer” Antipsychotika: Der Beitrag der Positronenemissionstomographie

2003

Almost fifteen years of research with Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT) have led to a profound understanding of the relationships between antipsychotic doses and plasma levels on the one hand and occupancy of (striatal) D 2 -like dopamine receptors on the other hand as well as with the associated clinical effects and side effects. Furthermore, with the development of clinically atypical" antipsychotics PET studies helped to generate hypotheses regarding the essential pharmacological properties of this heterogeneous class of drugs. Possible mechanisms of action include combined D 2 -/5-HT 2 antagonism, preferential mesolimbic binding, a…