Int J Parasitol Parasites Wildl
December 2024
Micro-computed tomography (micro-CT) is an emerging tool in parasitology that can assist in analysing morphology and host-parasitic interactions. It is a non-destructive, cross-sectional imaging technique that offers good resolution and the ability to create three-dimensional (3D) reconstructions. Here, we used micro-CT to study , which is a zoonotic pentastome parasite that infects dogs and ruminants throughout the world.
View Article and Find Full Text PDFSpinal cord injury (SCI) can result in the permanent loss of mobility, sensation, and autonomic function. Secondary degeneration after SCI both initiates and propagates a hostile microenvironment that is resistant to natural repair mechanisms. Consequently, exogenous stem cells have been investigated as a potential therapy for repairing and recovering damaged cells after SCI and other CNS disorders.
View Article and Find Full Text PDFPurpose Of This Review: Manipulating or re-engineering the damaged human spinal cord to achieve neuro-recovery is one of the foremost challenges of modern science. Addressing the restricted permission of neural cells and topographically organised neural tissue for self-renewal and spontaneous regeneration, respectively, is not straightforward, as exemplified by rare instances of translational success. This review assembles an understanding of advances in nanomedicine for spinal cord injury (SCI) and related clinical indications of relevance to attempts to design, engineer, and target nanotechnologies to multiple molecular networks.
View Article and Find Full Text PDFNeural tissue engineering aims to restore the function of nervous system tissues using biocompatible cell-seeded scaffolds. Graphene-based scaffolds combined with stem cells deserve special attention to enhance tissue regeneration in a controlled manner. However, it is believed that minor changes in scaffold biomaterial composition, internal porous structure, and physicochemical properties can impact cellular growth and adhesion.
View Article and Find Full Text PDFReducing the extent of secondary degeneration following spinal cord injury (SCI) is necessary to preserve function, but treatment options have thus far been limited. A combination of the ion channel inhibitors Lomerizine (Lom), YM872 and oxATP, to inhibit voltage-gated Ca channels, Ca permeable AMPA receptors, and purinergic P2X receptors respectively, effectively limits secondary consequences of injury in and models of CNS injury. Here, we investigated the efficacy of these inhibitors in a clinically relevant model of SCI.
View Article and Find Full Text PDFBackground: Following partial injury to the central nervous system, cells beyond the initial injury site undergo secondary degeneration, exacerbating loss of neurons, compact myelin and function. Changes in Ca flux are associated with metabolic and structural changes, but it is not yet clear how flux through specific ion channels contributes to the various pathologies. Here, partial optic nerve transection in adult female rats was used to model secondary degeneration.
View Article and Find Full Text PDFStudies have shown that a combined application of several ion channel inhibitors immediately after central nervous system injury can inhibit secondary degeneration. However, for clinical use, it is necessary to determine how long after injury the combined treatment of several ion channel inhibitors can be delayed and efficacy maintained. In this study, we delivered Ca entry-inhibiting P2X7 receptor antagonist oxidized-ATP and AMPA receptor antagonist YM872 to the optic nerve injury site an iPRECIO pump immediately, 6 hours, 24 hours and 7 days after partial optic nerve transection surgery.
View Article and Find Full Text PDFCombinations of Ca channel inhibitors have been proposed as an effective means to prevent excess Ca flux and death of neurons and glia following neurotrauma in vivo. However, it is not yet known if beneficial outcomes such as improved viability have been due to direct effects on intracellular Ca concentrations. Here, the effects of combinations of Lomerizine (Lom), 2,3-dioxo-7-(1H-imidazol-1-yl)6-nitro-1,2,3,4-tetrahydro-1-quinoxalinyl]acetic acid monohydrate (YM872), 3,5-dimethyl-1-adamantanamine (memantine (Mem)) and/or adenosine 5'-triphosphate periodate oxidized sodium salt (oxATP) to block voltage-gated Ca channels, Ca permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, NMDA receptors and purinergic P2X receptors (P2XR) respectively, on Ca concentration and viability of rat primary mixed cortical (MC) cultures exposed to hydrogen peroxide (HO) insult, were assessed.
View Article and Find Full Text PDFSeveral recent studies have demonstrated that TAT and other arginine-rich cell penetrating peptides (CPPs) have intrinsic neuroprotective properties in their own right. Examples, we have demonstrated that in addition to TAT, poly-arginine peptides (R8 to R18; containing 8-18 arginine residues) as well as some other arginine-rich peptides are neuroprotective in vitro (in neurons exposed to glutamic acid excitotoxicity and oxygen glucose deprivation) and in the case of R9 in vivo (after permanent middle cerebral artery occlusion in the rat). Based on several lines of evidence, we propose that this neuroprotection is related to the peptide's endocytosis-inducing properties, with peptide charge and arginine residues being critical factors.
View Article and Find Full Text PDFGlutamate excitotoxicity contributes to damage following injury to the central nervous system via mechanisms including changes in the expression of receptors, calcium overload, oxidative stress and cell death. Excitotoxicity is triggered by glutamate binding to receptors, including calcium permeable AMPA receptors, which can be upregulated under injury conditions. However, the transcriptional response of AMPA receptor regulatory proteins to excitotoxic conditions is unknown.
View Article and Find Full Text PDFNeurotrauma results in the progressive degeneration of neurons and glia surrounding the initial injury. Disruptions to myelin structure are a feature of these injuries and are thought to be triggered by excess calcium (Ca2+) influx into myelinating oligodendrocytes and/or their precursor cells. Calcium ions enter oligodendrocytes through a range of receptors including voltage gated calcium channels, N-methyl-D-aspartate (NMDA) receptors, Ca2+ permeable α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, and purinergic P2X7 receptors.
View Article and Find Full Text PDFSecondary degeneration contributes substantially to structural and functional deficits following traumatic injury to the CNS. While it has been proposed that oxidative stress is a feature of secondary degeneration, contributing reactive species and resultant oxidized products have not been clearly identified in vivo. The study is designed to identify contributors to, and consequences of, oxidative stress in a white matter tract vulnerable to secondary degeneration.
View Article and Find Full Text PDFFollowing neurotrauma, cells beyond the initial trauma site undergo secondary degeneration, with excess Ca2+ a likely trigger for loss of neurons, compact myelin and function. Treatment using inhibitors of specific Ca2+ channels has shown promise in preclinical studies, but clinical trials have been disappointing and combinatorial approaches are needed. We assessed efficacy of multiple combinations of three Ca2+ channel inhibitors at reducing secondary degeneration following partial optic nerve transection in rat.
View Article and Find Full Text PDFSecondary degeneration of nerve tissue adjacent to a traumatic injury results in further loss of neurons, glia and function, via mechanisms that may involve oxidative stress. However, changes in indicators of oxidative stress have not yet been demonstrated in oligodendrocytes vulnerable to secondary degeneration in vivo. We show increases in the oxidative stress indicator carboxymethyl lysine at days 1 and 3 after injury in oligodendrocytes vulnerable to secondary degeneration.
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