Search results for " brain"
showing 10 items of 985 documents
Is 2-deoxy-2-[(18)F]fluoro-D-glucose PET/CT acquisition from the upper thigh to the vertex of skull useful in oncological patients?
2015
Aim:To assess whether performing routinely 2-deoxy-2-[18F]fluoro-D-glucose PET/CT (18FDG PET/CT) scanfrom the upper thigh to the vertex of skull is clinically relevant. Materials and Methods: 3502 (1634 female; mean-age 60+16) consecutive patients undergoing 18 FDG PET/CT were retrospectively analyzed. Patients were divided in 10 groups according to primar y malignancy. Chi-square analysis was used to assess differences among proportions. A p value < 0.05 was considered significant. Results: 18 FDG PET/CT was positive in head district in 130/3502 (3,7%) patients. In all patients lesions were unknown before PET/CT examination. PET/CT showed 158 positive brain/head uptake in the 130 patients.…
Auditory and Cognitive Deficits Associated with Acquired Amusia after Stroke: A Magnetoencephalography and Neuropsychological Follow-Up Study
2010
Acquired amusia is a common disorder after damage to the middle cerebral artery (MCA) territory. However, its neurocognitive mechanisms, especially the relative contribution of perceptual and cognitive factors, are still unclear. We studied cognitive and auditory processing in the amusic brain by performing neuropsychological testing as well as magnetoencephalography (MEG) measurements of frequency and duration discrimination using magnetic mismatch negativity (MMNm) recordings. Fifty-three patients with a left (n = 24) or right (n = 29) hemisphere MCA stroke (MRI verified) were investigated 1 week, 3 months, and 6 months after the stroke. Amusia was evaluated using the Montreal Battery of …
Frequency-specific network activity predicts bradykinesia severity in Parkinson’s disease
2021
Highlights • Parallel subnetworks are affected in bradykinesia. • The primary motor and the premotor cortex are common nodes with task-specificity. • Beta activity decreases, gamma activity increases with improvement of bradykinesia. • Subthalamic stimulation reduces beta, increases gamma power in ipsilateral cortex. • Subnetworks act with frequency-specific oscillations.
Peritumoral perfusion and proton spectroscopic MR imaging in the differentiation of gliomas and solitary metastases
2015
Purpose: To asses the value of peritumoural perfusion-weighted and proton spectroscopic MR imaging in preoperative grading of gliomas and in differentiating between primary gliomas and solitary metastases. Methods and Materials: Ten low-grade gliomas, eight high-grade gliomas, and ten metastases were prospectively evaluated with MR imaging, dynamic susceptibility contrast-enhanced perfusion imaging, and single-voxel proton MR spectroscopy before surgical resection or stereotactic biopsy. Maximal rCBV values and maximal Cho/Cr ratios were calculated from peritumoural region surrounding the tumour. Tumour grade presumed with these values was compared to histopathologic grading. Differences in…
Mapping the onset and progression of atrophy in familial frontotemporal lobar degeneration
2005
Background: Frontotemporal lobar degeneration (FTLD) may be inherited as an autosomal dominant disease. Studying patients "at risk" for developing FTLD can provide insights into the earliest onset and evolution of the disease. Method: We carried out approximately annual clinical, MRI, and neuropsychological assessments on an asymptomatic 51 year old "at risk" family member from a family with FTLD associated with ubiquitin-positive and tau-negative inclusion bodies. We used non-linear (fluid) registration of serial MRI to determine areas undergoing significant regional atrophy at different stages of the disease. Results: Over the first 26 months of the study, the patient remained asymptomati…
Vascular Senescence: A Potential Bridge Between Physiological Aging and Neurogenic Decline
2021
The adult mammalian brain contains distinct neurogenic niches harboring populations of neural stem cells (NSCs) with the capacity to sustain the generation of specific subtypes of neurons during the lifetime. However, their ability to produce new progeny declines with age. The microenvironment of these specialized niches provides multiple cellular and molecular signals that condition NSC behavior and potential. Among the different niche components, vasculature has gained increasing interest over the years due to its undeniable role in NSC regulation and its therapeutic potential for neurogenesis enhancement. NSCs are uniquely positioned to receive both locally secreted factors and adhesion-…
Evaluation of the aptitude to cross the BBB of a new dopamine aminoacidic prodrug
2012
One of the most important factors limiting the development of new drugs for the CNS is the ability to cross the BBB which is a barrier that controls the entrance and exit of both endogenous and exogenous compounds. BBB expresses several transport systems that carry actively into the brain important nutrients (e.g. glucose and amino acids) and are able to import or export various xenobiotics including drugs and their metabolites. The content of active in the brain depends on the overall difference between the drug uptake and drug efflux processes [1]. Dopamine (DA) is a crucial neurotransmitter; its striatal depletion is responsible of clinical signs of Parkinson’s disease (PD). Owing to the…
Optimization of the KNN Supervised Classification Algorithm as a Support Tool for the Implantation of Deep Brain Stimulators in Patients with Parkins…
2019
Deep Brain Stimulation (DBS) of the Subthalamic Nuclei (STN) is the most used surgical treatment to improve motor skills in patients with Parkinson&rsquo
Neurofibrillary tangles and neuropil threads as a cause of dementia in Parkinson’s disease
1997
Alzheimer’s disease (AD) and Parkinson’s disease (PD) are the most common age-related degenerative disorders of the human brain. Both diseases involve multiple neuronal systems and are the consequences of cytoskeletal abnormalities. In AD susceptible neurons produce neurofibrillary changes, while in Parkinson’s disease, they develop Lewy bodies. In AD six developmental stages can be distinguished on account of the predictable manner in which the neurofibrillary changes spread across the cerebral cortex. During the course of PD numerous limbic determined parts of the brain undergo specific lesions regulating endocrine and autonomic functions. In general, the extranigral destructions are in t…
Neural networks engaged in milliseconds and seconds time processing: evidence from transcranial magnetic stimulation and patients with cortical or su…
2009
Here, we review recent transcranial magnetic stimulation studies and investigations in patients with neurological disease such as Parkinson's disease and stroke, showing that the neural processing of time requires the activity of wide range-distributed brain networks. The neural activity of the cerebellum seems most crucial when subjects are required to quickly estimate the passage of brief intervals, and when time is computed in relation to precise salient events. Conversely, the circuits involving the striatum and the substantia nigra projecting to the prefrontal cortex (PFC) are mostly implicated in supra-second time intervals and when time is processed in conjunction with other cognitiv…