scholarly journals A Century of Brain Regeneration Phenomena and Neuromorphological Research Advances, 1890s–1990s—Examining the Practical Implications of Theory Dynamics in Modern Biomedicine

2022 ◽  
Vol 9 ◽  
Author(s):  
Frank W. Stahnisch
Keyword(s):  
Nervous System ◽  
20Th Century ◽  
Theoretical Research ◽  
Clinical Neurology ◽  
Electron Microscopic ◽  
Brain Regeneration ◽  
Structural Plastic ◽  
The Impact ◽  
The Brain

The modern thesis regarding the “structural plastic” properties of the brain, as reactions to injuries, to tissue damage, and to degenerative cell apoptosis, can hardly be seen as expendable in clinical neurology and its allied disciplines (including internal medicine, psychiatry, neurosurgery, radiology, etc.). It extends for instance to wider research areas of clinical physiology and neuropsychology which almost one hundred years ago had been described as a critically important area for the brain sciences and psychology alike. Yet the mounting evidence concerning the range of structural neuroplastic phenomena beyond the significant early 3 years of childhood has shown that there is a progressive building up and refining of neural circuits in adaptation to the surrounding environment. This review essay explores the history behind multiple biological phenomena that were studied and became theoretically connected with the thesis of brain regeneration from Santiago Ramón y Cajal’s pioneering work since the 1890s to the beginning of the American “Decade of the Brain” in the 1990s. It particularly analyzes the neuroanatomical perspectives on the adaptive capacities of the Central Nervous System (CNS) as well as model-like phenomena in the Peripheral Nervous System (PNS), which were seen as displaying major central regenerative processes. Structural plastic phenomena have assumed large implications for the burgeoning field of regenerative or restorative medicine, while they also pose significant epistemological challenges for related experimental and theoretical research endeavors. Hereafter, early historical research precursors are examined, which investigated brain regeneration phenomena in non-vertebrates at the beginning of the 20th century, such as in light microscopic studies and later in electron microscopic findings that substantiated the presence of structural neuroplastic phenomena in higher cortical substrates. Furthermore, Experimental physiological research in hippocampal in vivo models of regeneration further confirmed and corroborated clinical physiological views, according to which “structural plasticity” could be interpreted as a positive regenerative CNS response to brain damage and degeneration. Yet the underlying neuroanatomical mechanisms remained to be established and the respective pathway effects were only conveyed through the discovery of neural stem cells in in adult mammalian brains in the early 1990s. Experimental results have since emphasized the genuine existence of adult neurogenesis phenomena in the CNS. The focus in this essay will be laid here on questions of the structure and function of scientific concepts, the development of research schools among biomedical investigators, as well as the impact of new data and phenomena through innovative methodologies and laboratory instruments in the neuroscientific endeavors of the 20th century.

The significance of the detection of oxidative and reducing tissue enzymes for questions of localization in the brain

1927 ◽  
Vol 23 (6-7) ◽  
pp. 613-621
Author(s):  
М. Bielschowsky ◽  
М. Rose
Keyword(s):  
Nervous System ◽  
The Right ◽  
The Brain

Histology of the nervous system is served, for the purpose of research, almost exclusively by stained slices from fixed objects. As fixing agents, mainly alcohol, formaldehyde and mixtures of chromium salts are used, which produce more or less fast clotting of tissue colloids, as a result of which the in vivo structure of cells with their processes is very much changed. To what extent our preparations give us the right to conclude about the living structure of cells and especially about the processes running or already running intra vitam is an old and much debated problem.

Effects of CSF Properties on Brain Response Under Impact Loading

2009 ◽  
Author(s):  
M. S. Chafi ◽  
V. Dirisala ◽  
G. Karami ◽  
M. Ziejewski
Keyword(s):  
Human Head ◽  
Brain Response ◽  
Pia Mater ◽  
Mechanical Shocks ◽  
The Central Nervous System ◽  
Simultaneous Loading ◽  
The Impact ◽  
Impact Experiments ◽  
The Brain

In the central nervous system, the subarachnoid space is the interval between the arachnoid membrane and the pia mater. It is filled with a clear, watery liquid called cerebrospinal fluid (CSF). The CSF buffers the brain against mechanical shocks and creates buoyancy to protect it from the forces of gravity. The relative motion of the brain due to a simultaneous loading is caused because the skull and brain have different densities and the CSF surrounds the brain. The impact experiments are usually carried out on cadavers with no CSF included because of the autolysis. Even in the cadaveric head impact experiments by Hardy et al. [1], where the specimens are repressurized using artificial CSF, this is not known how far this can replicate the real functionality of CSF. With such motivation, a special interest lies on how to model this feature in a finite element (FE) modeling of the human head because it is questionable if one uses in vivo CSF properties (i.e. bulk modulus of 2.19 GPa) to validate a FE human head against cadaveric experimental data.

scholarly journals Microglia motility depends on neuronal activity and promotes structural plasticity in the hippocampus

2019 ◽  
Author(s):  
Felix C. Nebeling ◽  
Stefanie Poll ◽  
Lena C. Schmid ◽  
Manuel Mittag ◽  
Julia Steffen ◽  
...  
Keyword(s):  
Neuronal Activity ◽  
Dendritic Spines ◽  
Synapse Formation ◽  
Brain Parenchyma ◽  
Two Photon ◽  
Contact Rates ◽  
Health And Disease ◽  
The Impact ◽  
The Brain

AbstractMicroglia, the resident immune cells of the brain, play a complex role in health and disease. They actively survey the brain parenchyma by physically interacting with other cells and structurally shaping the brain. Yet, the mechanisms underlying microglia motility and their significance for synapse stability, especially during adulthood, remain widely unresolved. Here we investigated the impact of neuronal activity on microglia motility and its implication for synapse formation and survival. We used repetitive two-photon in vivo imaging in the hippocampus of awake mice to simultaneously study microglia motility and their interaction with synapses. We found that microglia process motility depended on neuronal activity. Simultaneously, more dendritic spines emerged in awake compared to anesthetized mice. Interestingly, microglia contact rates with individual dendritic spines were associated with their stability. These results suggest that microglia are not only sensing neuronal activity, but participate in synaptic rewiring of the hippocampus during adulthood, which has profound relevance for learning and memory processes.

scholarly journals Visualizing the Potential Impairment of Polymyxin B to Central Nervous System Through MR Susceptibility-Weighted Imaging

2021 ◽  
Vol 12 ◽  
Author(s):  
Ni Zhang ◽  
Lichong Zhu ◽  
Qiuhong Ouyang ◽  
Saisai Yue ◽  
Yichun Huang ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Polymyxin B ◽  
Susceptibility Weighted Imaging ◽  
Gram Negative Bacteria ◽  
Severe Toxicity ◽  
Gram Negative ◽  
The Impact

Polymyxin B (PMB) exert bactericidal effects on the cell wall of Gram-negative bacteria, leading to changes in the permeability of the cytoplasmic membrane and resulting in cell death, which is sensitive to the multi-resistant Gram-negative bacteria. However, the severe toxicity and adverse side effects largely hamper the clinical application of PMB. Although the molecular pathology of PMB neurotoxicity has been adequately studied at the cellular and molecular level. However, the impact of PMB on the physiological states of central nervous system in vivo may be quite different from that in vitro, which need to be further studied. Therefore, in the current study, the biocompatible ultra-uniform Fe3O4 nanoparticles were employed for noninvasively in vivo visualizing the potential impairment of PMB to the central nervous system. Systematic studies clearly reveal that the prepared Fe3O4 nanoparticles can serve as an appropriate magnetic resonance contrast agent with high transverse relaxivity and outstanding biosafety, which thus enables the following in vivo susceptibility-weighted imaging (SWI) studies on the PMB-treated mice models. As a result, it is first found that the blood-brain barrier (BBB) of mice may be impaired by successive PMB administration, displaying by the discrete punctate SWI signals distributed asymmetrically across brain regions in brain parenchyma. This result may pave a noninvasive approach for in-depth studies of PMB medication strategy, monitoring the BBB changes during PMB treatment, and even assessing the risk after PMB successive medication in multidrug-resistant Gram-negative bacterial infected patients from the perspective of medical imaging.

scholarly journals A three-step model of stress management for health leaders

2018 ◽  
Vol 31 (3) ◽  
pp. 81-86
Author(s):  
Elizabeth Hartney
Keyword(s):  
Nervous System ◽  
Stress Management ◽  
Healthcare System ◽  
Stressful Environment ◽  
Step Model ◽  
System Functioning ◽  
Managing Stress ◽  
The Individual ◽  
The Impact ◽  
The Brain

The current healthcare system is often as highly stressful environment for patients, their families, and for the employees of the system. Health leaders also experience stress, which can have profound repercussions if not well managed. This article describes the impact of stress on the brain and nervous system functioning of health leaders, then, drawing on evidence from the literature, presents a three-step model for managing stress at the individual, team/organizational, and system levels.

scholarly journals Methylmercury Epigenetics

Toxics ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 56 ◽  
Author(s):  
Megan Culbreth ◽  
Michael Aschner
Keyword(s):  
Dna Methylation ◽  
Mirna Expression ◽  
Epigenetic Modifications ◽  
Nervous System Development ◽  
Gene Promoters ◽  
Toxic Response ◽  
The Impact ◽  
The Brain

Methylmercury (MeHg) has conventionally been investigated for effects on nervous system development. As such, epigenetic modifications have become an attractive mechanistic target, and research on MeHg and epigenetics has rapidly expanded in the past decade. Although, these inquiries are a recent advance in the field, much has been learned in regards to MeHg-induced epigenetic modifications, particularly in the brain. In vitro and in vivo controlled exposure studies illustrate that MeHg effects microRNA (miRNA) expression, histone modifications, and DNA methylation both globally and at individual genes. Moreover, some effects are transgenerationally inherited, as organisms not directly exposed to MeHg exhibited biological and behavioral alterations. miRNA expression generally appears to be downregulated consequent to exposure. Further, global histone acetylation also seems to be reduced, persist at distinct gene promoters, and is contemporaneous with enhanced histone methylation. Moreover, global DNA methylation appears to decrease in brain-derived tissues, but not in the liver; however, selected individual genes in the brain are hypermethylated. Human epidemiological studies have also identified hypo- or hypermethylated individual genes, which correlated with MeHg exposure in distinct populations. Intriguingly, several observed epigenetic modifications can be correlated with known mechanisms of MeHg toxicity. Despite this knowledge, however, the functional consequences of these modifications are not entirely evident. Additional research will be necessary to fully comprehend MeHg-induced epigenetic modifications and the impact on the toxic response.

scholarly journals Top 100 Publications as Measured by Altmetrics in the Field of Central Nervous System Inflammatory Demyelinating Disease

2019 ◽  
Vol 2019 ◽  
pp. 1-12
Author(s):  
Jee-Eun Kim ◽  
Yerim Kim ◽  
Kang Min Park ◽  
Dae Young Yoon ◽  
Jong Seok Bae
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Web Of Science ◽  
Demyelinating Disease ◽  
Impact Factors ◽  
Clinical Neurology ◽  
Novel Treatments ◽  
Number Of Citations ◽  
The Impact ◽  
Journal Impact

Background. Altmetrics analyze the visibility of articles in social media and estimate their impact on the general population. We performed an altmetric analysis of articles on central nervous system inflammatory demyelinating disease (CIDD) and investigated its correlation with citation analysis. Methods. Articles in the 91 journals comprising the “clinical neurology,” “neuroscience,” and “medicine, general, and internal” Web of Science categories were searched for their relevance to the CIDD topic. The Altmetric Explorer database was used to determine the Altmetric.com Attention Score (AAS) values of the selected articles. The papers with the top 100 AAS values were characterized. Results. Articles most frequently mentioned online were primarily published after 2014 and were published in journals with high impact factors. All articles except one were dealt with the issue of multiple sclerosis. Most were original articles, but editorials were also common. Novel treatments and risk factors are the most frequent topics. The AAS was weakly correlated with journal impact factors; however, no link was found between the AAS and the number of citations. Conclusions. We present the top 100 most frequently mentioned CIDD articles in online media using an altmetric approach. Altmetrics can rapidly offer alternative information on the impact of research based on a broader audience and can complement traditional metrics.

scholarly journals Prion propagation in mice lacking central nervous system NF-κB signalling

2008 ◽  
Vol 89 (6) ◽  
pp. 1545-1550 ◽  
Author(s):  
C. Julius ◽  
M. Heikenwalder ◽  
P. Schwarz ◽  
A. Marcel ◽  
M. Karin ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Immune Responses ◽  
Published Data ◽  
Histopathological Changes ◽  
Prion Infection ◽  
Prion Propagation ◽  
Proliferation Regulation ◽  
The Impact ◽  
The Brain

Prions induce highly typical histopathological changes including cell death, spongiosis and activation of glia, yet the molecular pathways leading to neurodegeneration remain elusive. Following prion infection, enhanced nuclear factor-κB (NF-κB) activity in the brain parallels the first pathological changes. The NF-κB pathway is essential for proliferation, regulation of apoptosis and immune responses involving induction of inflammation. The IκB kinase (IKK) signalosome is crucial for NF-κB signalling, consisting of the catalytic IKKα/IKKβ subunits and the regulatory IKKγ subunit. This study investigated the impact of NF-κB signalling on prion disease in mouse models with a central nervous system (CNS)-restricted elimination of IKKβ or IKKγ in nearly all neuroectodermal cells, including neurons, astrocytes and oligodendrocytes, and in mice containing a non-phosphorylatable IKKα subunit (IKKα AA/AA). In contrast to previously published data, the observed results showed no evidence supporting the hypothesis that impaired NF-κB signalling in the CNS impacts on prion pathogenesis.

scholarly journals Acute brain trauma

2016 ◽  
Vol 98 (1) ◽  
pp. 6-10 ◽  
Author(s):  
GT Martin
Keyword(s):  
20Th Century ◽  
21St Century ◽  
Head Injuries ◽  
Brain Trauma ◽  
Computer Calculations ◽  
Skull Deformity ◽  
The Impact ◽  
Primary Injury ◽  
The Brain

In the 20th century, the complications of head injuries were controlled but not eliminated. The wars of the 21st century turned attention to blast, the instant of impact and the primary injury of concussion. Computer calculations have established that in the first 5 milliseconds after the impact, four independent injuries on the brain are inflicted: 1) impact and its shockwave, 2) deceleration, 3) rotation and 4) skull deformity with vibration (or resonance). The recovery, pathology and symptoms after acute brain trauma have always been something of a puzzle. The variability of these four modes of injury, along with a variable reserve of neurones, explains some of this problem.

scholarly journals A conducting polymer with enhanced electronic stability applied in cardiac models

2016 ◽  
Vol 2 (11) ◽  
pp. e1601007 ◽  
Author(s):  
Damia Mawad ◽  
Catherine Mansfield ◽  
Antonio Lauto ◽  
Filippo Perbellini ◽  
Geoffrey W. Nelson ◽  
...  
Keyword(s):  
Nervous System ◽  
Beneficial Effect ◽  
Phytic Acid ◽  
Ex Vivo ◽  
Chitosan Film ◽  
In Vivo Experiments ◽  
Conductive System ◽  
The Brain ◽  
Operational Time

Electrically active constructs can have a beneficial effect on electroresponsive tissues, such as the brain, heart, and nervous system. Conducting polymers (CPs) are being considered as components of these constructs because of their intrinsic electroactive and flexible nature. However, their clinical application has been largely hampered by their short operational time due to a decrease in their electronic properties. We show that, by immobilizing the dopant in the conductive scaffold, we can prevent its electric deterioration. We grew polyaniline (PANI) doped with phytic acid on the surface of a chitosan film. The strong chelation between phytic acid and chitosan led to a conductive patch with retained electroactivity, low surface resistivity (35.85 ± 9.40 kilohms per square), and oxidized form after 2 weeks of incubation in physiological medium. Ex vivo experiments revealed that the conductive nature of the patch has an immediate effect on the electrophysiology of the heart. Preliminary in vivo experiments showed that the conductive patch does not induce proarrhythmogenic activities in the heart. Our findings set the foundation for the design of electronically stable CP-based scaffolds. This provides a robust conductive system that could be used at the interface with electroresponsive tissue to better understand the interaction and effect of these materials on the electrophysiology of these tissues.

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