Galactosylated dopamine enters into the brain, blocks the mesocorticolimbic system and modulates activity and scanning time in Naples high excitability rats

The role of CT-Angiography (CTA) in the diagnosis of cerebral aneurysms has not been definitively established. It depends mainly either on the low spreading of helical-CTs and on the quality of the reconstructive techniques in different equipment. Aim of this paper is to discuss certainties and controversies in the use of CTA in the diagnosis of cerebral aneurysms. CTA can be performed in conjunction with conventional CT with minimal additional scanning time, mainly important in emergency. CTA well-defines shape, size and orientation of the aneurysm, if the scans are free of artefacts and if it is possible to well subtract bones and veins. Technology improvements are awaited in the near future to shorten the time of acquisition, increasing the volume acquired and reducing artefacts. The use of multi-array systems of acquisition, more powerful algorithms to reduce artifacts and software able to define correctly the time of injection of the contrast medium could help to reach the goal of showing all the brain arteries free of artefacts and superimposed veins. At present CTA can substitute angiography in emergency when there is no time to perform angiography and when there is CTA evidence of an aneurysm associated with local haematoma.

Download Full-text

Fast magnetic resonance elastography with multiphase radial encoding and harmonic motion sparsity based reconstruction

Physics in Medicine and Biology ◽

10.1088/1361-6560/ac4a42 ◽

2022 ◽

Author(s):

Runke Wang ◽

Yu Chen ◽

Ruokun Li ◽

Suhao Qiu ◽

Zhiyong Zhang ◽

...

Keyword(s):

Magnetic Resonance ◽

Low Frequency ◽

Initial Position ◽

Magnetic Resonance Elastography ◽

Spatial Modulation ◽

Harmonic Motion ◽

Scanning Time ◽

Scan Time ◽

Reconstruction Performance ◽

The Brain

Abstract Objective: To achieve fast magnetic resonance elastography (MRE) at a low frequency for better shear modulus estimation of the brain. Approach: We proposed a multiphase radial DENSE MRE (MRD-MRE) sequence and an improved GRASP algorithm utilizing the sparsity of the harmonic motion (SH-GRASP) for fast MRE at 20 Hz. For the MRD-MRE sequence, the initial position encoded by one spatial modulation of magnetization (SPAMM) was decoded by an arbitrary number of readout blocks without increasing the number of phase offsets. Based on the harmonic motion, a modified total variation and temporal Fourier transform were introduced to utilize the sparsity in the temporal domain. Both phantom and brain experiments were carried out and compared with that from multiphase Cartesian DENSE-MRE (MCD-MRE), and conventional gradient echo sequence (GRE-MRE). Reconstruction performance was also compared with GRASP and compressed sensing. Main results: Results showed the scanning time of a fully sampled image with four phase offsets for MRD-MRE was only 1/5 of that from GRE-MRE. The wave patterns and estimated stiffness maps were similar to those from MCD-MRE and GRE-MRE. With SH-GRASP, the total scan time could be shortened by additional 4 folds, achieving a total acceleration factor of 20. Better metric values were also obtained using SH-GRASP for reconstruction compared with other algorithms. Significance: The MRD-MRE sequence and SH-GRASP algorithm can be used either in combination or independently to accelerate MRE, showing the potentials for imaging the brain as well as other organs.

Download Full-text

The effect of alcohol and nicotine abuse on gene expression in the brain

Nutrition Research Reviews ◽

10.1017/s0954422409990114 ◽

2009 ◽

Vol 22 (2) ◽

pp. 148-162 ◽

Cited By ~ 11

Author(s):

Traute Flatscher-Bader ◽

Peter A. Wilce

Keyword(s):

Gene Expression ◽

Drug Targets ◽

Molecular Mechanisms ◽

Drugs Of Abuse ◽

Human Subjects ◽

Common Mental Disorder ◽

Tobacco Consumption ◽

Western World ◽

Mesocorticolimbic System ◽

The Brain

Alcohol intake at levels posing an acute heath risk is common amongst teenagers. Alcohol abuse is the second most common mental disorder worldwide. The incidence of smoking is decreasing in the Western world but increasing in developing countries and is the leading cause of preventable death worldwide. Considering the longstanding history of alcohol and tobacco consumption in human societies, it might be surprising that the molecular mechanisms underlying alcohol and smoking dependence are still incompletely understood. Effective treatments against the risk of relapse are lacking. Drugs of abuse exert their effect manipulating the dopaminergic mesocorticolimbic system. In this brain region, alcohol has many potential targets including membranes and several ion channels, while other drugs, for example nicotine, act via specific receptors or binding proteins. Repeated consumption of drugs of abuse mediates adaptive changes within this region, resulting in addiction. The high incidence of alcohol and nicotine co-abuse complicates analysis of the molecular basis of the disease. Gene expression profiling is a useful approach to explore novel drug targets in the brain. Several groups have utilised this technology to reveal drug-sensitive pathways in the mesocorticolimbic system of animal models and in human subjects. These studies are the focus of the present review.

Download Full-text

Working memory capacity and the hemispheric organization of the brain

Behavioral and Brain Sciences ◽

10.1017/s0140525x01293923 ◽

2001 ◽

Vol 24 (1) ◽

pp. 121-122 ◽

Cited By ~ 2

Author(s):

Gabriele Gratton ◽

Monica Fabiani ◽

Paul M. Corballis

Keyword(s):

Working Memory ◽

Preliminary Data ◽

Working Memory Capacity ◽

Memory Capacity ◽

Distributed Model ◽

Memory Scanning ◽

Scanning Time ◽

The Brain

Different hypotheses about the mechanisms underlying working memory lead to different predictions about working memory capacity when information is distributed across the two hemispheres. We present preliminary data suggesting that memory scanning time (a parameter often associated with working memory capacity) varies depending on how information is subdivided across hemispheres. The data are consistent with a distributed model of working memory.

Download Full-text

Transcranial eddy current damping sensors for detection and imaging of hemorrhagic stroke: feasibility in benchtop experimentation

Neurosurgical FOCUS ◽

10.3171/2021.4.focus21121 ◽

2021 ◽

Vol 51 (1) ◽

pp. E15

Author(s):

Shane Shahrestani ◽

Ben A. Strickland ◽

Joshua Bakhsheshian ◽

William J. Mack ◽

Arthur W. Toga ◽

...

Keyword(s):

Eddy Current ◽

Hemorrhagic Stroke ◽

Maximum Diameter ◽

Scanning Time ◽

Eddy Current Damping ◽

Excellent Spatial Resolution ◽

Human Participants ◽

Diagnostic Technologies ◽

The Brain ◽

Blood Data

OBJECTIVE Spontaneous intracerebral hemorrhage occurs in an estimated 10% of stroke patients, with high rates of associated mortality. Portable diagnostic technologies that can quickly and noninvasively detect hemorrhagic stroke may prevent unnecessary delay in patient care and help rapidly triage patients with ischemic versus hemorrhagic stroke. As such, the authors aimed to develop a rapid and portable eddy current damping (ECD) hemorrhagic stroke sensor for proposed in-field diagnosis of hemorrhagic stroke. METHODS A tricoil ECD sensor with microtesla-level magnetic field strengths was constructed. Sixteen gelatin brain models with identical electrical properties to live brain tissue were developed and placed within phantom skull replicas, and saline was diluted to the conductivity of blood and placed within the brain to simulate a hemorrhage. The ECD sensor was used to detect modeled hemorrhages on benchtop models. Data were saved and plotted as a filtered heatmap to represent the lesion location. The individuals performing the scanning were blinded to the bleed location, and sensors were tangentially rotated around the skull models to localize blood. Data were also used to create heatmap images using MATLAB software. RESULTS The sensor was portable (11.4-cm maximum diameter), compact, and cost roughly $100 to manufacture. Scanning time was 2.43 minutes, and heatmap images of the lesion were produced in near real time. The ECD sensor accurately predicted the location of a modeled hemorrhage in all (n = 16) benchtop experiments with excellent spatial resolution. CONCLUSIONS Benchtop experiments demonstrated the proof of concept of the ECD sensor for rapid transcranial hemorrhagic stroke diagnosis. Future studies with live human participants are warranted to fully establish the feasibility findings derived from this study.

Download Full-text

A primer in interpretation of head CT scans

British Journal of Hospital Medicine ◽

10.12968/hmed.2019.80.11.c156 ◽

2019 ◽

Vol 80 (11) ◽

pp. C156-C161

Author(s):

Saminderjit Kular ◽

Andrew Martin

Keyword(s):

Computed Tomography ◽

Ct Scan ◽

Intracranial Haemorrhage ◽

Skull Fracture ◽

Ct Scans ◽

Head Ct ◽

Scanning Time ◽

Stroke Team ◽

Ct Head ◽

The Brain

Over recent years with the development of increasingly efficient scanners, the computed tomography (CT) scan of the head has become one of the most commonly requested initial investigations, used to provide an overview of the brain and its surrounding structures. In particular, the CT head scan has become significant in the trauma setting. With short scanning time, an investigation to confirm or exclude intracranial haemorrhage, skull fracture or stroke can now be performed in a matter of seconds. This article provides physicians with a structure for reading a CT head scan, to help identify key findings that may warrant further specialist neurosurgical or stroke team referral.

Download Full-text