scholarly journals Comparative Studies of Polysialic Acids Derived from Five Different Vertebrate Brains

2020 ◽  
Vol 21 (22) ◽  
pp. 8593
Author(s):  
Yi Yang ◽  
Ryo Murai ◽  
Yuka Takahashi ◽  
Airi Mori ◽  
Masaya Hane ◽  
...  
Keyword(s):  
Brain Function ◽  
Polysialic Acid ◽  
Molecular Size ◽  
Structural Features ◽  
Normal Brain ◽  
Brain Functions ◽  
Hydration Effect ◽  
Polysialic Acids ◽  
Direct Binding ◽  
Chain Lengths

Polysialic acid (polySia/PSA) is a linear homopolymer of sialic acid (Sia) that primarily modifies the neural cell adhesion molecule (NCAM) in mammalian brains. PolySia-NCAM not only displays an anti-adhesive function due to the hydration effect, but also possesses a molecule-retaining function via a direct binding to neurologically active molecules. The quality and quantity of polySia determine the function of polySia-NCAM and are considered to be profoundly related to the maintenance of normal brain functions. In this study, to compare the structures of polySia-NCAM in brains of five different vertebrates (mammals, birds, reptiles, amphibians, and fish), we adopted newly developed combinational methods for the analyses. The results revealed that the structural features of polySia considerably varied among different species. Interestingly, mice, as a mammal, possess eminently distinct types of polySia, in both quality and quantity, compared with those possessed by other animals. Thus, the mouse polySia is of larger quantities, of longer and more diverse chain lengths, and of a larger molecular size with higher negative charge, compared with polySia of other species. These properties might enable more advanced brain function. Additionally, it is suggested that the polySia/Sia ratio, which likely reflects the complexity of brain function, can be used as a new promising index to evaluate the intelligence of different vertebrate brains.

scholarly journals Cortical Brain Functions – The Brodmann Legacy in the 21st Century

2017 ◽  
Vol 39 (04) ◽  
pp. 261-270
Author(s):  
Daniel Damiani ◽  
Anna Maria Nascimento ◽  
Leticia Kühl Pereira
Keyword(s):  
Brain Function ◽  
Imaging Techniques ◽  
Normal Brain ◽  
Functional Neuroanatomy ◽  
Brain Functions ◽  
Topographic Organization ◽  
Normal Brain Function ◽  
Magnetic Resonance Imaging Techniques ◽  
Functional Map ◽  
Functional Areas

AbstractIn 1909, Korbinian Brodmann described 52 functional brain areas, 43 of them found in the human brain. More than a century later, his devoted functional map was incremented by Glasser et al in 2016, using functional nuclear magnetic resonance imaging techniques to propose the existence of 180 functional areas in each hemisphere, based on their cortical thickness, degree of myelination (cortical myelin content), neuronal interconnection, topographic organization, multitask answers, and assessment in their resting state. This opens a huge possibility, through functional neuroanatomy, to understand a little more about normal brain function and its functional impairment in the presence of a disease.

Autophagy and proteostasis adjustment role in normal brain function and neurodegenerative disorders

2021 ◽  
Author(s):  
Moataz Dowaidar
Keyword(s):  
Neurodegenerative Diseases ◽  
Brain Function ◽  
Normal Brain ◽  
Brain Health ◽  
Brain Functions ◽  
Normal Brain Function ◽  
Membrane Bound ◽  
Synaptic Changes ◽  
The Stability

Higher cognitive brain functions are based on neural network complexity and diversity of neuronal identities. Understanding how the brain works is still a major scientific topic, not only because it consists of tens of billions of neuronal and glial cells, but also because the flexibility of the nervous system involves altering synaptic linkages and their abundance. Individual synapses include an average composition of around 1,000–3,000 different proteins, with 100,000 protein units in total. This complexity is further amplified molecularly.De novo protein synthesis is recognized to be crucial for the stability of synaptic changes in converting short-term memories to long-term memories. Neurons have a distinct compartmentalization degree and can maintain and adjust their proteomas without relying on the cell body. Dendrites make up more than 75% of the total space of a neuron and can produce hundreds of synapses, requiring transport of membrane-bound cargo and organelles via intricate dendritic arborization and long axons.Neurons are exposed to a number of stressful situations that may compromise proteostasis during their lengthy lifespan. The accumulation of aberrant protein aggregates in the form of soluble oligomers, fibrils and large protein inclusions defines most neurodegenerative diseases, emphasizing the significance of preserving the integrity of the proteome for health. As a result, the ability of synapses to keep their unique features for long periods of time or to change their composition in response to physiological indications poses a tight, ongoing challenge to the proteostasis network. This article explores the basic mechanisms that govern proteostasis adjustment and their involvement in normal brain function and neurodegenerative diseases. These discoveries are also assessed as to their implications for the future development of therapeutic strategies to alleviate disease conditions and extend brain health.

scholarly journals Protective effects of polysialic acids (PSAs) and its mimics on the nervous system after injury

2021 ◽  
Vol 26 (4) ◽  
pp. 643-647
Author(s):  
Wei-jiang Zhao ◽  
Jia-hui He ◽  
Shuang-xi Chen
Keyword(s):  
Nervous System ◽  
Tissue Repair ◽  
Therapeutic Potential ◽  
Polysialic Acid ◽  
Normal Brain ◽  
Brain Circulation ◽  
Protective Effects ◽  
Neural Cell Adhesion Molecules ◽  
Neural Cell Adhesion ◽  
Polysialic Acids

Polysialic acid (PSA), a polymer of alpha-2,8 linked sialic acid residues, is a negatively charged macromolecular glycan mainly attached to neural cell adhesion molecules (NCAM). Studies have shown that PSA is not only essential for the development of normal brain circulation, but also for synaptic plasticity, learning and memory in adults. Although the occurrence, features, biosynthesis, and physiological roles of PSA and related effects on related diseases, including schizophrenia, bipolar disorder, neurodegenerative diseases and cancer, have been well reviewed, the important roles of PSA and its mimics in the regeneration of the nervous system following injury have not been well discussed. As a consequence, this article comprehensively reviews the effects of small organic compounds that simulate PSA, such as tegaserod and 5-nonyloxytryptamine (5-NOT), on the nervous system of mammals, suggesting that these mimetics may have tremendous therapeutic potential, especially for strategies aimed at tissue repair after injury of the nervous system.

Frequency decomposition and phase synchronization of the visual evoked potential using the empirical mode decomposition

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Byuckjin Lee ◽  
Byeongnam Kim ◽  
Sun K. Yoo
Keyword(s):  
Empirical Mode Decomposition ◽  
Brain Function ◽  
Visual Evoked Potential ◽  
Evoked Potential ◽  
Posterior Lobe ◽  
Time Frequency ◽  
Brain Functions ◽  
Mode Decomposition ◽  
Frequency Components ◽  
Visual Evoked

AbstractObjectivesThe phase characteristics of the representative frequency components of the Electroencephalogram (EEG) can be a means of understanding the brain functions of human senses and perception. In this paper, we found out that visual evoked potential (VEP) is composed of the dominant multi-band component signals of the EEG through the experiment.MethodsWe analyzed the characteristics of VEP based on the theory that brain evoked potentials can be decomposed into phase synchronized signals. In order to decompose the EEG signal into across each frequency component signals, we extracted the signals in the time-frequency domain with high resolution using the empirical mode decomposition method. We applied the Hilbert transform (HT) to extract the signal and synthesized it into a frequency band signal representing VEP components. VEP could be decomposed into phase synchronized δ, θ, α, and β frequency signals. We investigated the features of visual brain function by analyzing the amplitude and latency of the decomposed signals in phase synchronized with the VEP and the phase-locking value (PLV) between brain regions.ResultsIn response to visual stimulation, PLV values were higher in the posterior lobe region than in the anterior lobe. In the occipital region, the PLV value of theta band was observed high.ConclusionsThe VEP signals decomposed into constituent frequency components through phase analysis can be used as a method of analyzing the relationship between activated signals and brain function related to visual stimuli.

scholarly journals Fundamental functional differences between gyri and sulci: implications for brain function, cognition, and behavior

2021 ◽  
Vol 1 (1) ◽  
pp. 23-41
Author(s):  
Xi Jiang ◽  
Tuo Zhang ◽  
Shu Zhang ◽  
Keith M Kendrick ◽  
Tianming Liu
Keyword(s):  
Brain Function ◽  
Cell Biology ◽  
Functional Anatomy ◽  
Building Blocks ◽  
Functional Differentiation ◽  
Cortical Folding ◽  
Brain Functions ◽  
Functional Relationships ◽  
Structural Architecture ◽  
And Behavior

Abstract Folding of the cerebral cortex is a prominent characteristic of mammalian brains. Alterations or deficits in cortical folding are strongly correlated with abnormal brain function, cognition, and behavior. Therefore, a precise mapping between the anatomy and function of the brain is critical to our understanding of the mechanisms of brain structural architecture in both health and diseases. Gyri and sulci, the standard nomenclature for cortical anatomy, serve as building blocks to make up complex folding patterns, providing a window to decipher cortical anatomy and its relation with brain functions. Huge efforts have been devoted to this research topic from a variety of disciplines including genetics, cell biology, anatomy, neuroimaging, and neurology, as well as involving computational approaches based on machine learning and artificial intelligence algorithms. However, despite increasing progress, our understanding of the functional anatomy of gyro-sulcal patterns is still in its infancy. In this review, we present the current state of this field and provide our perspectives of the methodologies and conclusions concerning functional differentiation between gyri and sulci, as well as the supporting information from genetic, cell biology, and brain structure research. In particular, we will further present a proposed framework for attempting to interpret the dynamic mechanisms of the functional interplay between gyri and sulci. Hopefully, this review will provide a comprehensive summary of anatomo-functional relationships in the cortical gyro-sulcal system together with a consideration of how these contribute to brain function, cognition, and behavior, as well as to mental disorders.

scholarly journals Cranioplasty Sinking Should Affect Normal Brain Function Mimicking Other Neurologic Illness: Fig 1.

2012 ◽  
Vol 33 (4) ◽  
pp. e65-e65
Author(s):  
M. del Mar Carmona Abellán ◽  
M. Murie Fernández ◽  
P. Esteve Belloch
Keyword(s):  
Brain Function ◽  
Normal Brain ◽  
Normal Brain Function

THE INSULA: ISLAND OF REIL

2015 ◽  
Vol 86 (11) ◽  
pp. e4.155-e4
Author(s):  
Ray Wynford-Thomas ◽  
Rob Powell
Keyword(s):  
Speech Processing ◽  
Brain Function ◽  
Insular Cortex ◽  
Normal Brain ◽  
Temporal Epilepsy ◽  
Normal Brain Function ◽  
Temporal Structures ◽  
Hypermotor Seizures ◽  
Posterior Insula ◽  
As Effects

Just as ‘no man is an island’, despite its misleading name, the insula is not an island. Sitting deeply within the cerebrum, the insular cortex and its connections play an important role in both normal brain function and seizure generation. Stimulating specific areas of the insula can produce somatosensory, viscerosensory, somatomotor and visceroautonomic symptoms, as well as effects on speech processing and pain. Insular onset seizures are rare, but may mimic both temporal and extra-temporal epilepsy and if not recognised, may lead to failure of epilepsy surgery. We therefore highlight the semiology of insular epilepsy by discussing three cases with different auras. Insular onset seizures can broadly be divided into three main types both anatomically and according to seizure semiology:1. Seizures originating in the antero-inferior insula present with laryngeal constriction, along with visceral and gustatory auras (similar to those originating in medial temporal structures).2. Antero-superior onset seizures can have a silent onset, but tend to propagate rapidly to motor areas causing focal motor or hypermotor seizures.3. Seizures originating in the posterior insula present with contralateral sensory symptoms.

Computational Study for Molecular Properties of Some of the Isolated Chemicals from Leaves Extract of Guiera Senegalensis as Aluminium Corrosion Inhibitor

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
A. M. Ayuba ◽  
◽  
M. Abubakar ◽  
Keyword(s):  
Molecular Dynamics ◽  
Quantum Chemical ◽  
Energy Gap ◽  
Computational Study ◽  
Physical Adsorption ◽  
Chemical Constituents ◽  
Molecular Size ◽  
Structural Features ◽  
Inhibitor Molecule ◽  
Fukui Indices

The present work describes the computational methods for the corrosion inhibition of aluminium using three selected chemical constituents (5-methyldihydroflavasperone, 5-methylflavasperone and methoxylated naphthyl butanone) reportedly obtained from the leaves extract of Guirea senegalensis. Quantum chemical calculations including EHOMO, ELUMO, energy gap (ΔE), electronegativity (χ), global hardness (η) and fraction of electrons transfer from the inhibitor molecule to the aluminium surface (ΔN) were calculated. The local reactive sites through Fukui indices which explain the effect of structural features of these components in relation to electrophilic and nucleophilic point of attack were evaluated. The similarities in quantum chemical parameters for the compounds obtained revealed that the adsorption strengths of the molecules will be mostly determined by molecular size rather than electronic structure parameters. Fukui indices showed that the point of interaction of inhibitor molecule with the Al(l10) surface were through aromatic carbon atom rich in pi-electrons and oxygen atom of the alkanone functional group in the inhibitor molecules. Molecular dynamics simulations describing the adsorption behavior of the inhibitor molecule on Al(110) surface through Forcite quench molecular dynamics were carried out. The compounds were found to all obey the mechanism of physical adsorption because of their relatively low adsorption energies.

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