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Topic Review
Myotonia Congenita
Myotonia congenita (MC) is a rare disorder characterized by stiffness and weakness of the limb and trunk muscles. Mutations in the SCN4A gene encoding the alpha-subunit of the voltage-gated sodium channel Nav1.4 have been reported to be responsible for sodium channel myotonia (SCM). The Nav1.4 channel is expressed in skeletal muscles, and its related channelopathies affect skeletal muscle excitability, which can manifest as SCM, paramyotonia, and periodic paralysis. In this study, the missense mutation p.V445M was identified in two individual families with MC. To determine the functional consequences of having a mutated Nav1.4 channel, whole-cell patch-clamp recording of transfected Chinese hamster ovary cells was performed. Evaluation of the transient Na+ current found that a hyperpolarizing shift occurs at both the activation and inactivation curves with an increase of the window currents in the mutant channels. The Nav1.4 channel’s co-expression with the Navβ4 peptide can generate resurgent Na+ currents at repolarization following a depolarization. The magnitude of the resurgent currents is higher in the mutant than in the wild-type (WT) channel. Although the decay kinetics are comparable between the mutant and WT channels, the time to the peak of resurgent Na+ currents in the mutant channel is significantly protracted compared with that in the WT channel. These findings suggest that the p.V445M mutation in the Nav1.4 channel results in an increase of both sustained and resurgent Na+ currents, which may contribute to hyperexcitability with repetitive firing and is likely to facilitate recurrent myotonia in SCM patients.
  • 1.5K
  • 29 Oct 2020
Topic Review
Cell Autonomous Mechanisms in Astrocytes in Neurodegenerative Diseases
Neurodegenerative disorders like Alzheimer’s disease (AD), Parkinson’s disease (PD), frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) affect millions of people worldwide, and as the average human lifespan increases, similarly grows the number of patients. Cognitive and motoric decline has been explained by the very apparent deterioration of neurons in various regions of the brain and spinal cord. However, more studies show that disease progression is greatly influenced by the vast population of glial cells. Astrocytes are traditionally considered star-shaped cells on which neurons rely heavily for their optimal homeostasis and survival. Increasing amounts of evidence depict how astrocytes lose their supportive functions while simultaneously gaining toxic properties during neurodegeneration. 
  • 1.5K
  • 12 Mar 2024
Topic Review
Uncoupling Proteins for Neurodegenerative Diseases
Most of the major retinal degenerative diseases are associated with significant levels of oxidative stress. One of the major sources contributing to the overall level of stress is the reactive oxygen species (ROS) generated by mitochondria. The driving force for ROS production is the proton gradient across the inner mitochondrial membrane. This gradient can be modulated by members of the uncoupling protein family, particularly the widely expressed UCP2. The overexpression and knockout studies of UCP2 in mice have established the ability of this protein to provide neuroprotection in a number of animal models of neurological disease, including retinal diseases. The expression and activity of UCP2 are controlled at the transcriptional, translational and post-translational levels, making it an ideal candidate for therapeutic intervention. 
  • 1.5K
  • 30 Jun 2022
Topic Review
Gut Microbiota and Parkinson’s Disease
Parkinson’s disease (PD) is the second-most prevalent neurodegenerative or neuropsychiatric disease, affecting 1% of seniors worldwide. The gut microbiota (GM) is one of the key access controls for most diseases and disorders. Disturbance in the GM creates an imbalance in the function and circulation of metabolites, resulting in unhealthy conditions. Any dysbiosis could affect the function of the gut, consequently disturbing the equilibrium in the intestine, and provoking pro-inflammatory conditions in the gut lumen, which send signals to the central nervous system (CNS) through the vagus enteric nervous system, possibly disturbing the blood–brain barrier. The neuroinflammatory conditions in the brain cause accumulation of α-syn, and progressively develop PD. An important aspect of understanding and treating the disease is access to broad knowledge about the influence of dietary supplements on GM.
  • 1.5K
  • 05 Aug 2022
Topic Review
Mechanical Properties of Implant in Lumbar Interbody Fusion
Over the last decade, pedicle fixation systems have evolved and modifications in spinal fusion techniques have been developed to increase fusion rates and improve clinical outcomes after lumbar interbody fusion (LIF). Regarding materials used for screw and rod manufacturing, metals, especially titanium alloys, are the most popular resources. In the case of pedicle screws, that biomaterial can be also doped with hydroxyapatite, CaP, ECM, or tantalum. Other materials used for rod fabrication include cobalt–chromium alloys and nitinol (nickel–titanium alloy). In terms of mechanical properties, the ideal implant used in LIF should have high tensile and fatigue strength, Young’s modulus similar to that of the bone, and should be 100% resistant to corrosion to avoid mechanical failures.
  • 1.5K
  • 08 Jun 2022
Topic Review
Visual Hallucinations in Migraine and Epilepsy
Since the earliest descriptions of the simple visual hallucinations in migraine patients and in subjects suffering from occipital lobe epilepsy, several important issues have arisen in recognizing epileptic seizures of the occipital lobe, which often present with symptoms mimicking migraine. A detailed quantitative and qualitative clinical scrutiny of timing and characteristics of visual impairment can contribute to avoiding mistakes. Differential diagnosis, in children, might be challenging because of the partial clinical, therapeutic, and pathophysiological overlaps between the two diseases that often coexist. Ictal elementary visual hallucinations are defined by color, shape, size, location, movement, speed of appearance and duration, frequency, and associated symptoms and their progression. The evaluation of the distinctive clinical features of visual aura in migraine and visual hallucinations in occipital epilepsy could contribute to understanding the pathogenetic mechanisms of these two conditions. 
  • 1.5K
  • 04 May 2023
Topic Review
Picein
Picein is a herbal agent that has been investigated in only a few studies. Picein is the active ingredient of several herbs and can thus be extracted from different types of plants, which renders it widely available. To date, picein has shown to exhibit antioxidant and anti-inflammatory properties in cellular and plant studies.
  • 1.5K
  • 31 Oct 2022
Topic Review
People with Aphasia
People with Aphasia (PWA) are individuals who experience difficulties in one or more aspects of communication, such as the ability to speak, understand, read and write, due to acquired brain damage (e.g.stroke, dementia, brain tumour, traumatic brain injury).  
  • 1.5K
  • 27 Oct 2020
Topic Review
Mechanisms of Pain Modulation
A review of the pathophysiology of pain and its treatment, from a surgical point of view has been published (Sola RG, Pulido P. Neurosurgical Traatment of Pain. Brain Sci. 2022, 12(11), 1584; https://doi.org/10.3390/brainsci12111584) There are pain syndromes of difficult medical control.In these cases, surgical treatment may be an excellent alternative. The bases on which the different surgical approaches are based are described. The attached table shows a very schematic view of the neurosurgical treatment of pain.      
  • 1.5K
  • 22 Jan 2023
Topic Review
β-Amyloid and Tau Protein in Alzheimer’s Disease
Alzheimer’s disease (AD) is one of the major causes of dementia and its incidence represents approximately 60–70% of all dementia cases worldwide. Many theories have been proposed to describe the pathological events in AD, including deterioration in cognitive function, accumulation of β-amyloid, and tau protein hyperphosphorylation. Infection as well as various cellular molecules, such as apolipoprotein, micro-RNA, calcium, ghrelin receptor, and probiotics, are associated with the disruption of β-amyloid and tau protein hemostasis.
  • 1.5K
  • 11 Aug 2023
Topic Review
Arterial Hypertension and Tension-Type Headache
Arterial hypertension (AH) is a prevalent condition worldwide and is the key risk factor for non-fatal and fatal cardiovascular complications. Tension-type headache (TTH) is the most common type of primary headache and is considered a common everyday headache.
  • 1.5K
  • 11 Oct 2021
Topic Review
Brain Lesion Theory
The term Brain lesion theory is a colloquialism which generally refers to the idea that brain lesions and traumatic brain injury are associated with aggressive and violent behaviour, criminality and anti-sociality . The concept of a correlation between brain injury and violent or aggressive behaviour has a strong basis in scientific literature and has been explored across multiple disciplines including forensics, psychology and sociology. Most findings in psychology suggest that the correlation between brain injury and aggression is specific to frontal lobe injury. There’s is little evidence to suggest that damage to other areas of the brain correlates with aggression. The correlations between frontal lobe injury and aggression have important implications in terms of function localisation in the brain. Function localisation is the idea that certain functions are specific certain areas of the brain. There is evidence to suggest that the frontal lobe is responsible for the control of cognitive skills like judgment and emotion regulation. Consequently, damage to the frontal lobe may lead to loss of control and impairment in social/emotional judgement therefore reducing a person’s ability to inhibit negative emotion and as a consequence increase aggressive responses. However, it is important to note that the evidence for a correlation between frontal lobe injury and aggression is heavily based on case study and consequently cannot be used to imply a causal factor in either direction. Further, aggression, violence and anti-sociality also correlate with alcoholism, abuse and a number of psychological, environmental and biological factors thus even if there was evidence for a causal link between brain injury and aggression it cannot be concluded that brain injury alone causes aggression.
  • 1.5K
  • 01 Dec 2022
Topic Review
Ursolic and Oleanolic Acids
Ursolic and oleanolic acids are secondary plant metabolites that are known to be involved in the plant defence system against water loss and pathogens. Nowadays these triterpenoids are also regarded as potential pharmaceutical compounds, compounds or triterpenoid-enriched plant extracts exert various beneficial effects, including anti-oxidative, anti-inflammatory and anticancer, on model systems of both human or animal origin. Some of those effects have been linked to the ability of ursolic and oleanolic acids to modulate intracellular antioxidant systems and also inflammation and cell death-related pathways.
  • 1.5K
  • 07 May 2021
Topic Review
Treating Traumatic Brain Injuries
Traumatic brain injury (TBI) is defined as an injury caused by an external force that results in the disruption of normal brain function. In the United States, between 2016–2017, there were approximately 451,000 cases of TBI that resulted in hospitalization. The most common mechanisms of injury contributing to TBI were unintentional falls and motor vehicle crashes.
  • 1.4K
  • 05 Aug 2021
Topic Review
Psychophysiological perspectives on emotion regulation
Several studies have suggested a correlation between heart rate variability (HRV), emotion regulation (ER), and consequent psychopathological conditions. Specifically, recent data seem to support the hypothesis that low-frequency heart rate variability (LF-HRV), an index of sympathetic cardiac control, correlates with worse ER and specific psychopathological dimensions. The present work aims to review the previous findings on these topics and integrate them from two main cornerstones of this perspective: Porges’ Polyvagal Theory and Thayer and Lane’s Neurovisceral Integration Model, which are necessary to understand these associations better. For this reason, based on these two approaches, we point out that low HRV is associated with emotional dysregulation and transversal psychopathological conditions. This understanding is beneficial as a theoretical ground from which to start for further research studies and as a starting point for new theoretical perspectives useful in clinical practice. 
  • 1.4K
  • 22 Sep 2021
Topic Review
Antimyostatin Treatment
Myostatin, also known as growth and differentiation factor 8 (GDF-8), was identified in 1997 by McPherron and Lee.
  • 1.4K
  • 09 Jun 2021
Topic Review
Applying CADD for Neurodegenerative Diseases
Neurodegenerative diseases (NDs) including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, and Huntington’s disease are incurable and affect millions of people worldwide. The development of treatments for this unmet clinical need is a major global research challenge. Computer-aided drug design (CADD) methods minimize the huge number of ligands that could be screened in biological assays, reducing the cost, time, and effort required to develop new drugs. 
  • 1.4K
  • 07 May 2021
Topic Review
Tryptophan Dysmetabolism and Quinolinic Acid in Neurodegenerative Diseases
Evidence suggests that neuroinflammation is involved in both depression and neurodegenerative diseases. The kynurenine pathway, generating metabolites which may play a role in pathogenesis, is one of several competing pathways of tryptophan metabolism. A disturbed tryptophan metabolism with increased activity of the kynurenine pathway and production of quinolinic acid may result in deficiencies in tryptophan and derived neurotransmitters. Quinolinic acid is an N-methyl-D-aspartate receptor agonist, and raised levels in CSF, together with increased levels of inflammatory cytokines, have been reported in mood disorders. Increased quinolinic acid has also been observed in neurodegenerative diseases, including Parkinson’s disease, Alzheimer’s disease, amyotrophic lateral sclerosis, and HIV-related cognitive decline. 
  • 1.4K
  • 29 Jul 2022
Topic Review
Neurofibromatosis and Schwannomatosis
Neurofibromatosis (NF) is a neurocutaneous syndrome characterized by the development of tumors of the central or peripheral nervous system including the brain, spinal cord, organs, skin, and bones. There are three types of NF: NF1 accounting for 96% of all cases, NF2 in 3%, and schwannomatosis (SWN) in <1%. The NF1 gene is located on chromosome 17q11.2, which encodes for a tumor suppressor protein, neurofibromin, that functions as a negative regulator of Ras/MAPK and PI3K/mTOR signaling pathways. The NF2 gene is identified on chromosome 22q12, which encodes for merlin, a tumor suppressor protein related to ezrin-radixin-moesin that modulates the activity of PI3K/AKT, Raf/MEK/ERK, and mTOR signaling pathways. In contrast, molecular insights on the different forms of SWN remain unclear. Inactivating mutations in the tumor suppressor genes SMARCB1 and LZTR1 are considered responsible for a majority of cases.
  • 1.4K
  • 08 Jun 2021
Topic Review
Neuromelanin in Parkinson’s Disease: Tyrosine Hydroxylase and Tyrosinase
Parkinson’s disease (PD) is an aging-related disease and the second most common neurodegenerative disease after Alzheimer’s disease. The main symptoms of PD are movement disorders accompanied with deficiency of neurotransmitter dopamine (DA) in the striatum due to cell death of the nigrostriatal DA neurons. Two main histopathological hallmarks exist in PD: cytosolic inclusion bodies termed Lewy bodies that mainly consist of α-synuclein protein, the oligomers of which produced by misfolding are regarded to be neurotoxic, causing DA cell death; and black pigments termed neuromelanin (NM) that are contained in DA neurons and markedly decrease in PD.
  • 1.4K
  • 15 Apr 2022
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