Search results for " brain"
showing 10 items of 985 documents
Design, synthesis and biological evaluation of new anticancer drugs: FGFR inhibitors
2021
Fibroblast growth factor receptors (FGFRs) constitute a family of tyrosine kinases receptors (RTKs) that exert pivotal physiological functions in human embryonic and adult tissues. Hyperactivated FGFR signaling drives tumorigenesis in multiple cancer types, including lung and brain cancers. Great effort has been laid on the development of new compounds that specifically target the FGFR axis. However, cancer cell- based and microenvironmental resistance mechanisms against FGFR inhibitors often arise and are currently poorly understood. Furthermore, FGFR-targeted therapy often presents different side effects, e due to the broad biological spectrum of the FGFR signaling axis as well as to its …
Postpleistocene evolution of the brain?
1976
The number of extraneurons (Nc) has been calculated with the formulae of Jerison ('63) for prehistoric population samples to check the hypothesis that Nc may not only increase by increasing of cranial capacity but also by decreasing of body-weight (gracilisation). Body weight of skeletal populations has been estimated by the formula of Debetz ('67). Samples from the Western part of Europe and Egypt support the hypothesis, but Eastern europoid samples display opposite relations: Nc increases with robusticity. It seems (as Jerison already suggested) that Nc is no measurement of the level of behavior in the populations of H. sapiens; but it may point towards allometric differences between West…
Transient oligemia is associated with long-term changes in binding densities of cortical inhibitory GABAA receptors in the rat brain
2009
Recently, we could demonstrate in rats that a short transient oligemic period of only 20-minute duration, induced by systemic hypotension, resulted in a transient decline of spatial memory capacities without any histological damage over a subsequent period of 6 months. In our present study, we checked for more subtle alterations within the highly vulnerable hippocampal CA1 subfield using quantification of neuronal cell density and semi-quantitative analysis of the ischemia-sensitive protein MAP2. Since hippocampal excitatory and inhibitory neurotransmitter receptors are crucially involved in spatial memory processes, quantitative in vitro receptor autoradiography was performed using [(3)H]M…
Dissociable contributions of left and right dorsolateral prefrontal cortex in planning.
2010
It is well established that the mid-dorsolateral prefrontal cortex (dlPFC) plays a critical role in planning. Neuroimaging studies have yielded predominantly bilateral dlPFC activations, but the existence and nature of functionally specific contributions of left and right dlPFC have remained elusive. In recent experiments, 2 independent parameters have been identified which substantially determine planning: 1) the degree of interdependence between consecutive steps (search depth) and 2) the degree to which the configuration of the goal state renders the order of single steps either clearly evident or ambiguous (goal hierarchy). Thus, search depth affects the actual mental generation and eva…
The Cumulative Effect of Transient Synchrony States on Motor Performance in Parkinson's Disease.
2020
Bursts of beta frequency band activity in the basal ganglia of patients with Parkinson's disease (PD) are associated with impaired motor performance. Here we test in human adults whether small variations in the timing of movement relative to beta bursts have a critical effect on movement velocity and whether the cumulative effects of multiple beta bursts, both locally and across networks, matter.
Abnormal motor asymmetry only during bimanual movement in schizophrenic patients compared with healthy subjects.
2003
In schizophrenia, research on motor asymmetry has focused on the direction and the degree of handedness using unimanual motor tests and tasks. However, typically both hands collaborate in the production of most manual movements. This study explored motor asymmetry exhibited during unimanual and bimanual tasks in schizophrenic and healthy subjects using a new experimental motor battery. Specifically, the authors investigated the motor indices of laterality during finger-tapping and hand-turning tasks in four unimanual and four bimanual conditions in 84 schizophrenic and 31 healthy subjects, all right-handed. The schizophrenic patients showed reduced motor asymmetries only during bimanual tap…
Deriving electrophysiological brain network connectivity via tensor component analysis during freely listening to music
2020
Recent studies show that the dynamics of electrophysiological functional connectivity is attracting more and more interest since it is considered as a better representation of functional brain networks than static network analysis. It is believed that the dynamic electrophysiological brain networks with specific frequency modes, transiently form and dissolve to support ongoing cognitive function during continuous task performance. Here, we propose a novel method based on tensor component analysis (TCA), to characterize the spatial, temporal, and spectral signatures of dynamic electrophysiological brain networks in electroencephalography (EEG) data recorded during free music-listening. A thr…
AMPA receptor GluA2 subunit defects are a cause of neurodevelopmental disorders.
2019
AMPA receptors (AMPARs) are tetrameric ligand-gated channels made up of combinations of GluA1-4 subunits encoded by GRIA1-4 genes. GluA2 has an especially important role because, following post-transcriptional editing at the Q607 site, it renders heteromultimeric AMPARs Ca2+-impermeable, with a linear relationship between current and trans-membrane voltage. Here, we report heterozygous de novo GRIA2 mutations in 28 unrelated patients with intellectual disability (ID) and neurodevelopmental abnormalities including autism spectrum disorder (ASD), Rett syndrome-like features, and seizures or developmental epileptic encephalopathy (DEE). In functional expression studies, mutations lead to a dec…
Validation of N-terminal pro-brain natriuretic peptide cut-off values for risk stratification of pulmonary embolism
2014
The optimal N-terminal pro-brain natriuretic peptide (NT-proBNP) cut-off value for risk stratification of pulmonary embolism remains controversial. In this study we validated and compared different proposed NT-proBNP cut-off values in 688 normotensive patients with pulmonary embolism. During the first 30 days, 28 (4.1%) patients reached the primary outcome (pulmonary embolism-related death or complications) and 29 (4.2%) patients died. Receiver operating characteristic analysis yielded an area under the curve of 0.70 (0.60-0.80) for NT-proBNP. A cut-off value of 600 pg·mL(-1) was associated with the best prognostic performance (sensitivity 86% and specificity 50%) and the highest odds ratio…
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.