The action of agonists and an antagonist of GABA on the frequency composition of the electrical activity of various brain structures of rats

1993 ◽  
Vol 23 (1) ◽  
pp. 76-82
Author(s):  
A. V. Yarkov ◽  
V. V. Vorob'ev ◽  
G. I. Kovalev
Keyword(s):  
Electrical Activity ◽  
Brain Structures

scholarly journals Electrical Changes in Deeper Cortical Structures During Balanced General Anesthesia with the Aim on Inhalation Anesthetics Effects

2015 ◽  
Vol 15 (3) ◽  
pp. 21-29 ◽  
Author(s):  
M Fischer ◽  
M Drobny ◽  
B Saniova ◽  
E Bakosova ◽  
J Hamzik ◽  
...  
Keyword(s):  
Thoracic Surgery ◽  
Electrical Activity ◽  
General Anesthesia ◽  
Brain Activity ◽  
Brain Structures ◽  
Global Changes ◽  
Brain Electrical Activity ◽  
Inhalation Anesthetics ◽  
Modern Computer ◽  
New Research

Abstract There are many theories that attempt to explain the mechanisms of the effects of inhalation anesthetics - from simpler, pursuing individual effects of anesthetics on the level of the ion channels, to more complex that are looking for uniform global changes in brain activity common to several agents. However, we still don’t have satisfactory and adequate conclusions. We examined a sample of 39 patients undergoing thoracic surgery at the Clinic of Thoracic Surgery under general anesthesia (GA) and we registered their electroencephalographic (EEG) signals before and during operation. After induction of GA by intravenous (i.v.), we used inhalation anesthetics to maintain GA. We used sevoflurane (SEV) in 20 patients and desflurane (DES) in 19 patients. Then we obtained the EEG data and processed them through mathematical and statistical analysis, to discover any changes of electrical activity in the brain during thoracic surgery under GA. The era of digital recording EEG and present possibilities of modern computer techniques allow quantitative analysis of obtained data. We performed the analysis with the software LORETA (low resolution brain electromagnetic tomography). It is a relatively new research method, which in a similar way as computed tomography (CT) or magnetic resonance imaging (MRI) displays even deeper brain electrical activity, which is hiddeen for a classical EEG approach. We described the general changes in brain electrical activity of the deeper cortical structures within the traditional frequency bands (d, q, a, b and g) during GA at 5 mm spatial resolution. We have shown that the source of the well-known cortical EEG changes after the effect of used inhalation anesthetics is caused by changes situated in the deeper brain structures, particularly the limbic system. Significant changes occurred in the cingulate gyrus for most of an EEG frequency ranges. When comparing the data of patients anesthetised with SEV and DES we found similar changes within the d and q rhythms and then the global changes of EEG activity followed during GA.

scholarly journals Features of electrical brain activity in patients with multiple sclerosis, taking into account the comorbidity

2016 ◽  
pp. 20-26
Author(s):  
G. Chupryna ◽  
N. Svyrydova ◽  
V. Kozlov
Keyword(s):  
Multiple Sclerosis ◽  
Electrical Activity ◽  
Right Hemisphere ◽  
Spectral Power ◽  
Brain Activity ◽  
Brain Structures ◽  
Control Group ◽  
Brain Electrical Activity ◽  
Electrical Brain Activity ◽  
Beta 2

The results of the study of brain electrical activity in patients with multiple sclerosis (MS) in the aspect of comorbidity are shown in the work. EEG-study was conducted by 30 patients with MS in dynamics and 15 persons in the control group. The revealed changes in the EEG in patients with MS indicate the dysfunction of the mid-stem brain structures. In the general sample, 46.7% of patients had signs of a decrease in the ascending activating effects on the cortex from the side of the reticular formation of the brainstem. Signs of lowering the threshold of convulsive readiness and irrigation in the form of the alpha-wave activity of the alpha and beta-1 frequency bands, as well as acutewave-slow wave complexes and outbreaks of multiple (beta-1 and beta-2) -waves were detected. In 90% of patients in the general sample, there was a decrease in resistance to functional loads. It was established that in MS patients with comorbidity there is a significant (p <0.001) increase in the spectral power of brain electrical activity in the temporal leads of the right hemisphere in the ranges of theta and beta 1 frequencies and increasing the power of beta-2 activity in the occipital, parietal and temporal leads of both Hemispheres. In terms of the maximum absolute power in the beta-2 frequency range, the differences between the groups were for the large number of leadings of both hemispheres, which may reflect the specific features of the CNS activity, and be associated with the course of MS against the background of comorbidity, in particular pain syndromes.

The Reaction of Brain Structures with OsO4-Zinc-Iodide Stain

1971 ◽  
Vol 29 ◽  
pp. 272-273
Author(s):  
Werner J. Niklowitz
Keyword(s):  
Electron Microscope ◽  
Structural Changes ◽  
Mossy Fiber ◽  
Toxic Metal ◽  
Staining Technique ◽  
Brain Structures ◽  
Oxidase Inhibitor ◽  
Fiber Layer ◽  
Hippocampal Tissue ◽  
Zinc Iodide

After intoxication of rabbits with certain substances such as convulsant agents (3-acetylpyridine), centrally acting drugs (reserpine), or toxic metal compounds (tetraethyl lead) a significant observation by phase microscope is the loss of contrast of the hippocampal mossy fiber layer. It has been suggested that this alteration, as well as changes seen with the electron microscope in the hippocampal mossy fiber boutons, may be related to a loss of neurotransmitters. The purpose of these experiments was to apply the OsO4-zinc-iodide staining technique to the study of these structural changes since it has been suggested that OsO4-zinc-iodide stain reacts with neurotransmitters (acetylcholine, catecholamines).Domestic New Zealand rabbits (2.5 to 3 kg) were used. Hippocampal tissue was removed from normal and experimental animals treated with 3-acetylpyridine (antimetabolite of nicotinamide), reserpine (anti- hypertensive/tranquilizer), or iproniazid (antidepressant/monamine oxidase inhibitor). After fixation in glutaraldehyde hippocampal tissue was treated with OsO4-zinc-iodide stain and further processed for phase and electron microscope studies.

Measurement of spontaneous neuronal membrane activity by time lapse confocal microscopy

1995 ◽  
Vol 53 ◽  
pp. 972-973
Author(s):  
R H. Selinfreund ◽  
A. H. Cornell-Bell
Keyword(s):  
Membrane Potential ◽  
Confocal Microscopy ◽  
Patch Clamp ◽  
Electrical Activity ◽  
Time Lapse ◽  
Neuronal Firing ◽  
Neuronal Membrane ◽  
Pituitary Cells ◽  
Patch Clamp Recording ◽  
Spontaneous Electrical Activity

Cellular electrophysiological properties are normally monitored by standard patch clamp techniques . The combination of membrane potential dyes with time-lapse laser confocal microscopy provides a more direct, least destructive rapid method for monitoring changes in neuronal electrical activity. Using membrane potential dyes we found that spontaneous action potential firing can be detected using time-lapse confocal microscopy. Initially, patch clamp recording techniques were used to verify spontaneous electrical activity in GH4\C1 pituitary cells. It was found that serum depleted cells had reduced spontaneous electrical activity. Brief exposure to the serum derived growth factor, IGF-1, reconstituted electrical activity. We have examined the possibility of developing a rapid fluorescent assay to measure neuronal activity using membrane potential dyes. This neuronal regeneration assay has been adapted to run on a confocal microscope. Quantitative fluorescence is then used to measure a compounds ability to regenerate neuronal firing.The membrane potential dye di-8-ANEPPS was selected for these experiments. Di-8- ANEPPS is internalized slowly, has a high signal to noise ratio (40:1), has a linear fluorescent response to change in voltage.

Fate of sperm membrane in fertilized ova

1993 ◽  
Vol 51 ◽  
pp. 40-41
Author(s):  
Frank J. Longo
Keyword(s):  
Electron Microscopy ◽  
Electrical Activity ◽  
Sea Urchins ◽  
Morphological Changes ◽  
Integrated System ◽  
Electrophysiological Recording ◽  
Experimental Conditions ◽  
The Status ◽  
Sperm Membrane ◽  
Temporal And Spatial

Measurement of the egg's electrical activity, the fertilization potential or the activation current (in voltage clamped eggs), provides a means of detecting the earliest perceivable response of the egg to the fertilizing sperm. By using the electrical physiological record as a “real time” indicator of the instant of electrical continuity between the gametes, eggs can be inseminated with sperm at lower, more physiological densities, thereby assuring that only one sperm interacts with the egg. Integrating techniques of intracellular electrophysiological recording, video-imaging, and electron microscopy, we are able to identify the fertilizing sperm precisely and correlate the status of gamete organelles with the first indication (fertilization potential/activation current) of the egg's response to the attached sperm. Hence, this integrated system provides improved temporal and spatial resolution of morphological changes at the site of gamete interaction, under a variety of experimental conditions. Using these integrated techniques, we have investigated when sperm-egg plasma membrane fusion occurs in sea urchins with respect to the onset of the egg's change in electrical activity.

Fit Vs Faint: Assessing Work Causation in “Idiopathic Fall” Cases

2014 ◽  
Vol 19 (5) ◽  
pp. 3-12
Author(s):  
Lorne Direnfeld ◽  
David B. Torrey ◽  
Jim Black ◽  
LuAnn Haley ◽  
Christopher R. Brigham
Keyword(s):  
Blood Flow ◽  
Electrical Activity ◽  
Loss Of Consciousness ◽  
Brain Electrical Activity ◽  
Medical Terminology ◽  
Scientific Analysis ◽  
Medical Causation ◽  
The Individual ◽  
The Brain ◽  
Current Science

Abstract When an individual falls due to a nonwork-related episode of dizziness, hits their head and sustains injury, do workers’ compensation laws consider such injuries to be compensable? Bearing in mind that each state makes its own laws, the answer depends on what caused the loss of consciousness, and the second asks specifically what happened in the fall that caused the injury? The first question speaks to medical causation, which applies scientific analysis to determine the cause of the problem. The second question addresses legal causation: Under what factual circumstances are injuries of this type potentially covered under the law? Much nuance attends this analysis. The authors discuss idiopathic falls, which in this context means “unique to the individual” as opposed to “of unknown cause,” which is the familiar medical terminology. The article presents three detailed case studies that describe falls that had their genesis in episodes of loss of consciousness, followed by analyses by lawyer or judge authors who address the issue of compensability, including three scenarios from Arizona, California, and Pennsylvania. A medical (scientific) analysis must be thorough and must determine the facts regarding the fall and what occurred: Was the fall due to a fit (eg, a seizure with loss of consciousness attributable to anormal brain electrical activity) or a faint (eg, loss of consciousness attributable to a decrease in blood flow to the brain? The evaluator should be able to fully explain the basis for the conclusions, including references to current science.

Gastric electrical activity in normal neonates during the first year of life. Effect of lactation with breast milk and formula

2001 ◽  
Vol 120 (5) ◽  
pp. A209-A209
Author(s):  
G RIEZZO ◽  
R CASTELLANA ◽  
T DEBELLIS ◽  
F LAFORGIA ◽  
F INDRIO ◽  
...  
Keyword(s):  
Breast Milk ◽  
Electrical Activity ◽  
First Year ◽  
Gastric Electrical Activity ◽  
First Year Of Life ◽  
Normal Neonates
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