Dynamic Flow Velocity Mapping from Fluorescent Dye Transit Times in the Brain Surface Microcirculation of Anesthetized Rats and Mice

2016 ◽  
Vol 23 (6) ◽  
pp. 416-425 ◽  
Author(s):  
Ryo Hoshikawa ◽  
Hiroshi Kawaguchi ◽  
Hiroyuki Takuwa ◽  
Yoko Ikoma ◽  
Yutaka Tomita ◽  
...  
Keyword(s):  
Flow Velocity ◽  
Fluorescent Dye ◽  
Dynamic Flow ◽  
Velocity Mapping ◽  
Brain Surface ◽  
Anesthetized Rats ◽  
Transit Times ◽  
Rats And Mice ◽  
The Brain

scholarly journals Role of Nitric Oxide in the Elevation of Cerebral Blood Flow Induced by Acetylcholine and Anoxia in the Turtle

1996 ◽  
Vol 16 (2) ◽  
pp. 290-295 ◽  
Author(s):  
Patrick Hylland ◽  
Göran E. Nilsson ◽  
Peter L. Lutz
Keyword(s):  
Nitric Oxide ◽  
Blood Flow ◽  
Flow Velocity ◽  
Blood Flow Velocity ◽  
Freshwater Turtle ◽  
Brain Blood Flow ◽  
Brain Surface ◽  
Synthase Inhibitor ◽  
The Brain

Nitric oxide (NO)-dependent regulation of brain blood flow has hitherto not been studied in reptiles. By observing the brain surface (telencephalon) of the freshwater turtle (Trachemys scripta) with epiillumination microscopy, we show that topical application of acetylcholine (ACh) induces an increase in CBF velocity that can be completely blocked by the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME). The effect of L-NAME was reversed by L-arginine. Also, sodium nitroprusside (SNP), which decomposes to liberate NO, caused an increase in CBF velocity. By contrast, L-NAME could not block the increase in blood flow velocity caused by anoxia. Interestingly, superfusing the brain with ACh or SNP during anoxia had no effect on the blood flow velocity. The results suggest that NO is an endogenous vasodilator in the turtle brain, mediating the effects of ACh during normoxia. By contrast, anoxia does not rely on NO as a vasodilator.

Analytical Electron Microscopy (AEM) of Meningeal Cells Exposed to Particulate Cobalt During Studies of Experimental Epilepsy

1982 ◽  
Vol 40 ◽  
pp. 186-187
Author(s):  
R.G. Frederickson ◽  
R.G. Ulrich ◽  
J.L. Culberson
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Experimental Epilepsy ◽  
Metallic Cobalt ◽  
Experimental Animals ◽  
X Ray ◽  
Brain Surface ◽  
Meningeal Cells ◽  
Analytical Electron ◽  
The Brain

Metallic cobalt acts as an epileptogenic agent when placed on the brain surface of some experimental animals. The mechanism by which this substance produces abnormal neuronal discharge is unknown. One potentially useful approach to this problem is to study the cellular and extracellular distribution of elemental cobalt in the meninges and adjacent cerebral cortex. Since it is possible to demonstrate the morphological localization and distribution of heavy metals, such as cobalt, by correlative x-ray analysis and electron microscopy (i.e., by AEM), we are using AEM to locate and identify elemental cobalt in phagocytic meningeal cells of young 80-day postnatal opossums following a subdural injection of cobalt particles.

A new technique for the mapping of oxygen tension on the brain surface

2005 ◽  
Vol 25 (1_suppl) ◽  
pp. S543-S543
Author(s):  
Satoshi Kimura ◽  
Keigo Matsumoto ◽  
Yoshio Imahori ◽  
Katsuyoshi Mineura ◽  
Toshiyuki Itoh
Keyword(s):  
Oxygen Tension ◽  
New Technique ◽  
Brain Surface ◽  
A New Technique ◽  
The Brain

Frontier concept of rabi chip for intelligent humanoid

2018 ◽  
Vol 1 (2) ◽  
Author(s):  
Preecha Yupapin ◽  
Amiri I. S. ◽  
Ali J. ◽  
Ponsuwancharoen N. ◽  
Youplao P.
Keyword(s):  
Human Brain ◽  
Brain Function ◽  
Rabi Oscillation ◽  
Liquid Core ◽  
Brain Surface ◽  
Dipole Oscillation ◽  
On Chip ◽  
The Brain ◽  
Robotic Applications ◽  
Atom System

The sequence of the human brain can be configured by the originated strongly coupling fields to a pair of the ionic substances(bio-cells) within the microtubules. From which the dipole oscillation begins and transports by the strong trapped force, which is known as a tweezer. The tweezers are the trapped polaritons, which are the electrical charges with information. They will be collected on the brain surface and transport via the liquid core guide wave, which is the mixture of blood content and water. The oscillation frequency is called the Rabi frequency, is formed by the two-level atom system. Our aim will manipulate the Rabi oscillation by an on-chip device, where the quantum outputs may help to form the realistic human brain function for humanoid robotic applications.

scholarly journals Fast Nonsupervised 3D Registration of PET and MR Images of the Brain

1994 ◽  
Vol 14 (5) ◽  
pp. 749-762 ◽  
Author(s):  
Jean-François Mangin ◽  
Vincent Frouin ◽  
Isabelle Bloch ◽  
Bernard Bendriem ◽  
Jaime Lopez-Krahe
Keyword(s):  
Three Dimensional ◽  
Magnetic Resonance Images ◽  
Surface Matching ◽  
3D Registration ◽  
Matching Algorithm ◽  
Distance Map ◽  
Brain Surface ◽  
Discrete Surfaces ◽  
Positron Emission ◽  
The Brain

We propose a fully nonsupervised methodology dedicated to the fast registration of positron emission tomography (PET) and magnetic resonance images of the brain. First, discrete representations of the surfaces of interest (head or brain surface) are automatically extracted from both images. Then, a shape-independent surface-matching algorithm gives a rigid body transformation, which allows the transfer of information between both modalities. A three-dimensional (3D) extension of the chamfer-matching principle makes up the core of this surface-matching algorithm. The optimal transformation is inferred from the minimization of a quadratic generalized distance between discrete surfaces, taking into account between-modality differences in the localization of the segmented surfaces. The minimization process is efficiently performed via the precomputation of a 3D distance map. Validation studies using a dedicated brain-shaped phantom have shown that the maximum registration error was of the order of the PET pixel size (2 mm) for the wide variety of tested configurations. The software is routinely used today in a clinical context by the physicians of the Service Hospitalier Frédéric Joliot (>150 registrations performed). The entire registration process requires ∼5 min on a conventional workstation.

Development of a New Image-Guided Neuronavigation System: Mixed-Reality Projection Mapping Is Accurate and Feasible

2021 ◽  
Author(s):  
Tsukasa Koike ◽  
Taichi Kin ◽  
Shota Tanaka ◽  
Katsuya Sato ◽  
Tatsuya Uchida ◽  
...  
Keyword(s):  
Image Processing ◽  
Mixed Reality ◽  
Improve Patient Safety ◽  
Projection Mapping ◽  
Normalized Mutual Information ◽  
Image Guided ◽  
Brain Surface ◽  
Initial Surgery ◽  
Position And Orientation ◽  
The Brain

Abstract BACKGROUND Image-guided systems improve the safety, functional outcome, and overall survival of neurosurgery but require extensive equipment. OBJECTIVE To develop an image-guided surgery system that combines the brain surface photographic texture (BSP-T) captured during surgery with 3-dimensional computer graphics (3DCG) using projection mapping. METHODS Patients who underwent initial surgery with brain tumors were prospectively enrolled. The texture of the 3DCG (3DCG-T) was obtained from 3DCG under similar conditions as those when capturing the brain surface photographs. The position and orientation at the time of 3DCG-T acquisition were used as the reference. The correct position and orientation of the BSP-T were obtained by aligning the BSP-T with the 3DCG-T using normalized mutual information. The BSP-T was combined with and displayed on the 3DCG using projection mapping. This mixed-reality projection mapping (MRPM) was used prospectively in 15 patients (mean age 46.6 yr, 6 males). The difference between the centerlines of surface blood vessels on the BSP-T and 3DCG constituted the target registration error (TRE) and was measured in 16 fields of the craniotomy area. We also measured the time required for image processing. RESULTS The TRE was measured at 158 locations in the 15 patients, with an average of 1.19 ± 0.14 mm (mean ± standard error). The average image processing time was 16.58 min. CONCLUSION Our MRPM method does not require extensive equipment while presenting information of patients’ anatomy together with medical images in the same coordinate system. It has the potential to improve patient safety.

scholarly journals Falco-Tentorial Meningioma Producing Irreversible Midbrain Damage

2014 ◽  
Vol 21 (3) ◽  
pp. 301-304
Author(s):  
Amit Agrawal
Keyword(s):  
Ct Scan ◽  
Obstructive Hydrocephalus ◽  
Fatal Outcome ◽  
Surgical Decompression ◽  
Cerebral Veins ◽  
Tentorial Meningioma ◽  
Brain Surface ◽  
Deep Cerebral Veins ◽  
History Of ◽  
The Brain

Abstract Meningiomas arising from the falcotentorial junction are the rarest subgroup of tentorial menigiomas. Because of the distance from the brain surface and the surrounding deep cerebral veins these lesions are difficult and dangerous to treat surgically. A 45-year-old female presented with the history of progressive headache, disorientation, unsteadiness, and urinary incontinence for over 6 months. The patient developed difficulty in swallowing, and weakness of all four limbs for the last 7 days. CT scan brain plain and contrast showed a large well defined, homogenously enhancing mass lesion in the peineal region with compression of the upper brain stem and obstructive hydrocephalus. Inspite of the good surgical decompression the patient did not do well. As described in the literature, the compression of the midbrain can cause severe respiratory disturbances with fatal outcome; probably the similar mechanism resulted in poor outcome in present case. As we noticed the diffuse hypodensity in midbrain on CT scan, similar findings have been described in literature in cases of transtentorial herniation with poorer outcome.

scholarly journals Orexin receptor blockers: A tool for lowering alcohol intake and alcohol addictive behavior in the light of preclinical studies

2021 ◽  
Vol 75 (1) ◽  
pp. 959-969
Author(s):  
Kamila Czora-Poczwardowska ◽  
Radosław Kujawski ◽  
Julia Słyńko-Krzyżostaniak ◽  
Przemysław Ł. Mikołajczak ◽  
Michał Szulc
Keyword(s):  
Alcohol Intake ◽  
Selective Reduction ◽  
Optimization Methods ◽  
Sugar Solution ◽  
Behavioral Studies ◽  
Potential Efficacy ◽  
Bioactive Ligands ◽  
Receptor Blockers ◽  
Rats And Mice ◽  
The Brain

Abstract Alcohol use disorder (AUD) is a severe and globally widespread neurological and psychiatric problem. The treatment with currently used drugs often does not bring the expected effect. New optimization methods or directions in pharmacotherapy are still being sought. The group of bioactive ligands, targeted at neuropeptides called orexins (OXs) and their receptors (OXRs), affects a number of functions including ingestion, sleep-wake regulation, as well as the brain reward system which is the basis of addiction. The purpose of this paper is to systematize the knowledge in the field of preclinical behavioral studies on rodents (rats and mice) in several models of alcohol consumption using the OXRs antagonists. The results of the experiments indicated a potential efficacy of particular OXRs antagonists in the AUD treatment, especially those selectively blocking the OX1R. Among them, SB-334867 in the lowest effective dose of 3 mg/kg i.p. was most studied, as shown in the model of two-bottle choice using C57BL/6 mice. Moreover, this compound did not affect the reduction of cognitive functions. GSK1059865 was also involved in the selective reduction of ethanol intake, and simultaneously did not alter the consumption of sugar solution. The other group of selective OX2R antagonists, such as TCS-OX2-29 and LSN2424100, was less efficient. In summary, the OX1R antagonists proved to have the potential in AUD therapy, not only through the reduction of ethanol consumption but also in the treatment of coexisting behavioral and physiological disorders, such as insomnia and anxiety.

scholarly journals The current state of electrocorticography-based brain–computer interfaces

2020 ◽  
Vol 49 (1) ◽  
pp. E2 ◽  
Author(s):  
Kai J. Miller ◽  
Dora Hermes ◽  
Nathan P. Staff
Keyword(s):  
Functional Limitations ◽  
Brain Computer Interfaces ◽  
Brain Surface ◽  
Computer Interfaces ◽  
Brain Signals ◽  
Current State ◽  
Temporal And Spatial ◽  
Direct Feedback ◽  
The Brain ◽  
Lateral Sclerosis

Brain–computer interfaces (BCIs) provide a way for the brain to interface directly with a computer. Many different brain signals can be used to control a device, varying in ease of recording, reliability, stability, temporal and spatial resolution, and noise. Electrocorticography (ECoG) electrodes provide a highly reliable signal from the human brain surface, and these signals have been used to decode movements, vision, and speech. ECoG-based BCIs are being developed to provide increased options for treatment and assistive devices for patients who have functional limitations. Decoding ECoG signals in real time provides direct feedback to the patient and can be used to control a cursor on a computer or an exoskeleton. In this review, the authors describe the current state of ECoG-based BCIs that are approaching clinical viability for restoring lost communication and motor function in patients with amyotrophic lateral sclerosis or tetraplegia. These studies provide a proof of principle and the possibility that ECoG-based BCI technology may also be useful in the future for assisting in the cortical rehabilitation of patients who have suffered a stroke.

scholarly journals Development of Optically-Controlled “Living Electrodes” with Long-Projecting Axon Tracts for a Synaptic Brain-Machine Interface

2018 ◽  
Author(s):  
Dayo O. Adewole ◽  
Laura A. Struzyna ◽  
James P. Harris ◽  
Ashley D. Nemes ◽  
Justin C. Burrell ◽  
...  
Keyword(s):  
Brain Activity ◽  
Optical Recording ◽  
Neural Interfaces ◽  
New Class ◽  
Brain Surface ◽  
Long Term Performance ◽  
Term Performance ◽  
The Brain

AbstractAchievements in intracortical neural interfaces are compromised by limitations in specificity and long-term performance. A biological intermediary between devices and the brain may offer improved specificity and longevity through natural synaptic integration with deep neural circuitry, while being accessible on the brain surface for optical read-out/control. Accordingly, we have developed the first “living electrodes” comprised of implantable axonal tracts protected within soft hydrogel cylinders for the biologically-mediated monitoring/modulation of brain activity. Here we demonstrate the controlled fabrication, rapid axonal outgrowth, reproducible cytoarchitecture, and simultaneous optical stimulation and recording of neuronal activity within these engineered constructs in vitro. We also present their transplantation, survival, integration, and optical recording in rat cortex in vivo as a proof-of-concept for this neural interface paradigm. The creation and functional validation of these preformed, axon-based “living electrodes” is a critical step towards developing a new class of biohybrid neural interfaces to probe and modulate native circuitry.

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