Rugby players lose cognitive function and blood flow to the brain over one season, study shows

BMJ ◽  
2021 ◽  
pp. n2161
Author(s):  
Luke Taylor
Keyword(s):  
Blood Flow ◽  
Cognitive Function ◽  
Rugby Players ◽  
The Brain

scholarly journals Effects of Gastric Bypass Surgery on the Brain; Simultaneous Assessment of Glucose Uptake, Blood Flow, Neural Activity and Cognitive Function during Normo- and Hypoglycemia

2021 ◽  
Author(s):  
Kristina E. Almby ◽  
Martin H. Lundqvist ◽  
Niclas Abrahamsson ◽  
Sofia Kvernby ◽  
Markus Fahlström ◽  
...  
Keyword(s):  
Blood Flow ◽  
Gastric Bypass ◽  
Cerebral Blood Flow ◽  
Cognitive Function ◽  
Counterregulatory Hormones ◽  
Fdg Uptake ◽  
Post Surgery ◽  
Total Brain ◽  
Underlying Mechanisms ◽  
The Brain

While Roux-en-Y Gastric Bypass (RYGB) surgery in obese individuals typically improves glycemic control and prevents diabetes, it also frequently causes hypoglycemia. Previous work showed attenuated counter-regulatory responses following RYGB. The underlying mechanisms as well as the clinical consequences are unclear. <p>In this study, 11 non-diabetic subjects with severe obesity were investigated pre- and post-RYGB during hyperinsulinemic hypoglycemic clamps. Assessments were made of hormones, cognitive function, cerebral blood flow by arterial spin labeling, brain glucose metabolism by FDG PET and activation of brain networks by functional MRI. Post- vs pre-surgery, we found a general increase of cerebral blood flow but a decrease of total brain FDG uptake during normoglycemia. During hypoglycemia, there was a marked increase in total brain FDG uptake and this was similar for post- and pre-surgery, whereas hypothalamic FDG uptake was reduced. During hypoglycemia, attenuated responses of counterregulatory hormones and improvements in cognitive function were seen post-surgery. In early hypoglycemia, there was increased activation post- vs pre-surgery of neural networks in CNS regions implicated in glucose regulation such as the thalamus and hypothalamus. The results suggest adaptive responses of the brain that contribute to lowering of glycemia following RYGB, and the underlying mechanisms should be further elucidated.</p>

Effects of Gastric Bypass Surgery on the Brain; Simultaneous Assessment of Glucose Uptake, Blood Flow, Neural Activity and Cognitive Function during Normo- and Hypoglycemia

2021 ◽  
Author(s):  
Kristina E. Almby ◽  
Martin H. Lundqvist ◽  
Niclas Abrahamsson ◽  
Sofia Kvernby ◽  
Markus Fahlström ◽  
...  
Keyword(s):  
Blood Flow ◽  
Gastric Bypass ◽  
Cerebral Blood Flow ◽  
Cognitive Function ◽  
Counterregulatory Hormones ◽  
Fdg Uptake ◽  
Post Surgery ◽  
Total Brain ◽  
Underlying Mechanisms ◽  
The Brain

While Roux-en-Y Gastric Bypass (RYGB) surgery in obese individuals typically improves glycemic control and prevents diabetes, it also frequently causes hypoglycemia. Previous work showed attenuated counter-regulatory responses following RYGB. The underlying mechanisms as well as the clinical consequences are unclear. <p>In this study, 11 non-diabetic subjects with severe obesity were investigated pre- and post-RYGB during hyperinsulinemic hypoglycemic clamps. Assessments were made of hormones, cognitive function, cerebral blood flow by arterial spin labeling, brain glucose metabolism by FDG PET and activation of brain networks by functional MRI. Post- vs pre-surgery, we found a general increase of cerebral blood flow but a decrease of total brain FDG uptake during normoglycemia. During hypoglycemia, there was a marked increase in total brain FDG uptake and this was similar for post- and pre-surgery, whereas hypothalamic FDG uptake was reduced. During hypoglycemia, attenuated responses of counterregulatory hormones and improvements in cognitive function were seen post-surgery. In early hypoglycemia, there was increased activation post- vs pre-surgery of neural networks in CNS regions implicated in glucose regulation such as the thalamus and hypothalamus. The results suggest adaptive responses of the brain that contribute to lowering of glycemia following RYGB, and the underlying mechanisms should be further elucidated.</p>

Cerebral Vascular Transit Time in Alzheimer's Disease and Korsakoff's Psychosis and its Relation to Cognitive Function

1989 ◽  
Vol 154 (6) ◽  
pp. 790-796 ◽  
Author(s):  
R. Hunter ◽  
M. V. Merrick ◽  
C. Ferrington ◽  
A. Notghi ◽  
R. McLuskie ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cognitive Function ◽  
Transit Time ◽  
Gamma Camera ◽  
Input Function ◽  
Presenile Dementia ◽  
Bolus Intravenous Injection ◽  
Tomographic Projection ◽  
The Brain ◽  
Cerebral Vascular

The cerebral vascular transit time of 17 patients with presenile dementia of the Alzheimer type (ATD), nine abstinent patients with alcoholic Korsakoff's psychosis (KOR), and ten age-matched controls was determined by the bolus intravenous injection of pertechnetate. A gamma camera was used to estimate the median transit time (MTT) of the radioactive bolus in a planar (non-tomographic) projection normal to the vertex. The spread of the bolus arriving at the aortic arch was measured independently by a single external detector over the chest, and correction made for the transit time of this input function in calculating the net MTT for the head. Both ATD and KOR groups showed lengthened net MTTs, compatible with reduced cerebral blood flow, and which were correlated with reduced cognitive function. It is concluded that the method employed gives a simple, inexpensive estimate of function-related blood flow to the brain in presenile dementia.

scholarly journals Effect of Paprika Xanthophyll Supplementation on Cognitive Improvement in a Multitasking Exercise: A Pilot Study for Middle-Aged and Older Adults

Healthcare ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 81
Author(s):  
Asako Shirai ◽  
Tsuyoshi Wadazumi
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Cognitive Function ◽  
Oxygen Supply ◽  
Middle Aged ◽  
Cell Deformability ◽  
Flow Measurements ◽  
Cognitive Improvement ◽  
Blood Flow Measurements ◽  
The Brain

Ingestion of paprika xanthophyll supplement (PX), which has antioxidant effects, has been recently reported to maintain red blood cell deformability and improve oxygen delivery efficiency. Therefore, we hypothesized that the brain activation induced by multitasking exercise in middle-aged and older participants along with the improved erythrocyte oxygen-carrying efficiency induced by PX supplementation would show a synergistic effect, increasing oxygen supply to the brain and improving cognitive function more effectively. In study 1, cerebral blood flow measurements were conducted during the multitasking exercise and cognitive function tests to verify their effect on cognitive function. The results confirmed that cerebral blood flow increased during the exercise and cognitive function improved after the exercise. In study 2, we compared the effects of the multitasking exercise on cognitive function before and after PX supplementation in middle-aged and older participants to evaluate the effects of PX supplementation. The results suggested that PX supplementation enhanced the effects of active multitasking exercise on cognitive function. We speculate that the improvement of oxygen transport efficiency by PX resulted in more effective oxygen supply, allowing the multitasking exercise to occur more effectively, which was reflected as an improvement in the cognitive function.

Effects of Photobiomodulation on Changes in Cognitive Function and Regional Cerebral Blood Flow in Patients with Mild Cognitive Impairment: A Pilot Uncontrolled Trial

2021 ◽  
pp. 1-7
Author(s):  
Ji Soo Baik ◽  
Tae Young Lee ◽  
Nam Gyun Kim ◽  
Kyoungjune Pak ◽  
Sung-Hwa Ko ◽  
...  
Keyword(s):  
Blood Flow ◽  
Cerebral Blood Flow ◽  
Prefrontal Cortex ◽  
Cognitive Function ◽  
Regional Cerebral Blood Flow ◽  
Photon Emission ◽  
Anterior Cingulate ◽  
Emission Computed Tomography ◽  
Regional Cerebral Blood ◽  
The Brain

Background: Photobiomodulation (PBM) affects local blood flow regulation through nitric oxide generation, and various studies have reported on its effect on improving cognitive function in neurodegenerative diseases. However, the effect of PBM in the areas of the vertebral arteries (VA) and internal carotid arteries (ICA), which are the major blood-supplying arteries to the brain, has not been previously investigated. Objective: We aimed to determine whether irradiating PBM in the areas of the VA and ICA, which are the major blood-supplying arteries to the brain, improved regional cerebral blood flow (rCBF) and cognitive function. Methods: Fourteen patients with mild cognitive impairments were treated with PBM. Cognitive assessment and single-photon emission computed tomography were implemented at the baseline and at the end of PBM. Results: Regarding rCBF, statistically significant trends were found in the medial prefrontal cortex, lateral prefrontal cortex, anterior cingulate cortex, and occipital lateral cortex. Based on the cognitive assessments, statistically significant trends were found in overall cognitive function, memory, and frontal/executive function. Conclusion: We confirmed the possibility that PBM treatment in the VA and ICA areas could positively affect cognitive function by increasing rCBF. A study with a larger sample size is needed to validate the potential of PBM.

scholarly journals Effects of Gastric Bypass Surgery on the Brain; Simultaneous Assessment of Glucose Uptake, Blood Flow, Neural Activity and Cognitive Function during Normo- and Hypoglycemia

2021 ◽  
Author(s):  
Kristina E. Almby ◽  
Martin H. Lundqvist ◽  
Niclas Abrahamsson ◽  
Sofia Kvernby ◽  
Markus Fahlström ◽  
...  
Keyword(s):  
Blood Flow ◽  
Gastric Bypass ◽  
Cerebral Blood Flow ◽  
Cognitive Function ◽  
Counterregulatory Hormones ◽  
Fdg Uptake ◽  
Post Surgery ◽  
Total Brain ◽  
Underlying Mechanisms ◽  
The Brain

While Roux-en-Y Gastric Bypass (RYGB) surgery in obese individuals typically improves glycemic control and prevents diabetes, it also frequently causes hypoglycemia. Previous work showed attenuated counter-regulatory responses following RYGB. The underlying mechanisms as well as the clinical consequences are unclear. <p>In this study, 11 non-diabetic subjects with severe obesity were investigated pre- and post-RYGB during hyperinsulinemic hypoglycemic clamps. Assessments were made of hormones, cognitive function, cerebral blood flow by arterial spin labeling, brain glucose metabolism by FDG PET and activation of brain networks by functional MRI. Post- vs pre-surgery, we found a general increase of cerebral blood flow but a decrease of total brain FDG uptake during normoglycemia. During hypoglycemia, there was a marked increase in total brain FDG uptake and this was similar for post- and pre-surgery, whereas hypothalamic FDG uptake was reduced. During hypoglycemia, attenuated responses of counterregulatory hormones and improvements in cognitive function were seen post-surgery. In early hypoglycemia, there was increased activation post- vs pre-surgery of neural networks in CNS regions implicated in glucose regulation such as the thalamus and hypothalamus. The results suggest adaptive responses of the brain that contribute to lowering of glycemia following RYGB, and the underlying mechanisms should be further elucidated.</p>

Microvascular features that suggest effectors of blood-flow regulation in the brain: Evidence by SEM of corrosion casts of intracerebral vessels

1990 ◽  
Vol 48 (3) ◽  
pp. 274-275
Author(s):  
Enrico D.F. Motti ◽  
Hans-Georg Imhof ◽  
Gazi M. Yasargil
Keyword(s):  
Blood Flow ◽  
Perfusion Pressure ◽  
Corrosion Casts ◽  
Cerebral Microcirculation ◽  
Pial Arteries ◽  
Random Occurrence ◽  
Brain Arteries ◽  
Homogeneous Network ◽  
The Brain

Physiologists have devoted most attention in the cerebrovascular tree to the arterial side of the circulation which has been subdivided in three levels: 1) major brain arteries which keep microcirculation constant despite changes in perfusion pressure; 2) pial arteries supposed to be effectors regulating microcirculation; 3) intracerebral arteries supposed to be deprived of active cerebral blood flow regulating devices.The morphological search for microvascular effectors in the cerebrovascular bed has been elusive. The opaque substance of the brain confines in vivo investigation to the superficial pial arteries. Most morphologists had to limit their observation to the random occurrence of a favorable site in the practically two-dimensional thickness of diaphanized histological sections. It is then not surprising most investigators of the cerebral microcirculation refer to an homogeneous network of microvessels interposed between arterioles and venules.We have taken advantage of the excellent depth of focus afforded by the scanning electron microscope (SEM) to investigate corrosion casts obtained injecting a range of experimental animals with a modified Batson's acrylic mixture.

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.

Basic Ideas and Principles for Quantifying Regional Blood Flow with Nuclear Medical Techniques

1996 ◽  
Vol 35 (05) ◽  
pp. 181-185 ◽  
Author(s):  
H. Herzog
Keyword(s):  
Blood Flow ◽  
Nuclear Medicine ◽  
Regional Blood Flow ◽  
Visual Presentation ◽  
Regional Cerebral Blood ◽  
Basic Principles ◽  
Parametric Images ◽  
Major Application ◽  
Basic Ideas ◽  
The Brain

SummaryThe measurement of blood flow in various organs and its visual presentation in parametric images is a major application in nuclear medicine. The purpose of this paper is to summarize the most important nuclear medicine procedures used to quantify regional blood flow. Starting with the first concepts introduced by Fick and later by Kety-Schmidt the basic principles of measuring global and regional cerebral blood are discussed and their relationships are explained. Different applications and modifications realized first in PET- and later in SPECT-studies of the brain and other organs are described. The permeability and the extraction of the different radiopharmaceuticals are considered. Finally some important instrumental implications are compared.

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