Caenorhabditis elegans in Computational Research
Theodore B. Achacoso, William S. Yamamoto in AY's Neuroanatomy of C. elegans for Computation, 2022
381 neurons with 92 glial/support cells and 302 neurons with 56 glial/support cells comprise the male and hermaphrodite nervous systems, respectively. The general structure of the C. elegans nervous system is made up of two units. 20 cells of a nerve ring are contained in the pharynx, and is the central region of the neuropil in the animal. The other unit is composed of the rest of the neuropil, which are (1) a ventral cord, the main process bundle that emanates from the nerve ring, (2) a dorsal cord, axons of motor neurons that originate in the ventral cord and enter the dorsal cord via commissures, and (3) four sublateral processes that run anteriorly and posteriorly from the nerve ring (Figure 1.2). In this worm, neurons are grouped into the 9 identified nervous system ganglia.
Brain swelling, raised intracranial pressure and hypoxia-related brain injury
Helen Whitwell, Christopher Milroy, Daniel du Plessis in Forensic Neuropathology, 2021
Dark neurons in contrast have the following attributes (Figure 12.16):A monotonous, often shrunken appearance.Basophilic with H&E staining, having a dark blue perikaryal and dendritic cytoplasm.Slight eosinophilia may be superimposed giving a dark blue-red tint with H&E staining stain.Apical dendrites may have an irregular, corkscrew-shaped appearance.The shrunken, dark-stained nucleus may be indistinct within the cell body since it blends into the compacted perikaryal cytoplasm.Nucleoli though still discernable.Affected neurons may be separated from adjacent neuropil, especially with paraffin embedded tissue and are often scattered among histologically normal neurons (Jortner 2006).
Degenerative Diseases of the Nervous System
Philip B. Gorelick, Fernando D. Testai, Graeme J. Hankey, Joanna M. Wardlaw in Hankey's Clinical Neurology, 2020
Microscopic pathology shows: Numerous, large pale (achromatic) ballooned neurons in the basal ganglia and the motor and premotor cortex (layers III, V, and VI). These are intensely neurofilament protein positive (NFP+). These are not specific for CBD, but are found less prominently in PSP, Pick's disease, frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17), and AD.Neuropil threads: numerous and widespread threadlike processes in gray and white matter in the cortex, cerebral white matter, internal capsule, striatum, thalamic fasciculus, cerebral peduncle, and pons (Figures 16.59–16.61).Globose NFTs in the substantia nigra, locus ceruleus, and raphe nuclei.Pick's body–like tau inclusions in the cortex (layers II and III).Astrocytic plaques in focal atrophic cortices.Coiled bodies in oligodendrocytes (tau-positive fibers coiled around nucleus).Corticospinal tract degeneration.
Phytochemical constituents and protective efficacy of Schefflera arboricola L. leaves extract against thioacetamide-induced hepatic encephalopathy in rats
Published in Biomarkers, 2022
Ali M. El-Hagrassi, Abeer F. Osman, Mostafa E. El-Naggar, Noha A. Mowaad, Sahar Khalil, Manal A. Hamed
In haematoxylin and eosin-stained sections, the cerebral cortex of the control group showed normal apparent intact neurons with rounded vesicular nuclei. The surrounding neuropil contains glial cells and nerve fibres (Figure 12(a)). In the TAA group, there was obvious neuronal loss and most of the neurons of the cerebral cortex showed degenerative changes with many shrunken darkly stained nuclei, accompanied by perineuronal vacuoles. Moderate congestion of cerebral blood vessels and reactive glial cells infiltration were observed in the TAA group (Figure 12(b)). Whereas sections of the cerebral cortex of TAA pre-treated rats with 100 mg/kg b.wt. of plant extract revealed mild protective efficacy with the persistence of areas of neuronal degeneration and glial cells infiltration. Minimal congestion of cerebral blood vessels was observed. Some neurons appeared normal (Figure 12(c)). Conspicuously, TAA pre-treated rats with 200 mg/kg b.wt. of the plant extract showed a higher level of improvement. Most of the neurons appeared normal. There were minimal degenerative changes in sporadic neurons with minimal glial cells infiltration (Figure 12(d)).
Altered hippocampal expression and function of cytosolic phospholipase A2 (cPLA2) in temporal lobe epilepsy (TLE)
Published in Neurological Research, 2022
Akash Bera, Arpna Srivastava, Vivek Dubey, Aparna Banerjee Dixit, Manjari Tripathi, M C Sharma, Sanjeev Lalwani, P Sarat Chandra, Jyotirmoy Banerjee
Previous studies demonstrated that seizure activates glutamate signalling through cPLA2, which increases MMP levels and decreases tight junction protein expression levels, resulting in BBB dysfunction [13]. The neuropil is remodelled by a reduction in the levels of tight junction proteins and an increased propensity for leakage of the BBB. Rempe et al. (2018) demonstrated that cPLA2 inhibitor ATK prevents seizure-induced barrier leakage and normalizes MMP levels as well as tight junction protein levels [13]. The neurotransmitter glutamate exerts its effects by activating glutamate receptors. We have previously shown that endogenous NMDA receptor function contributes to the generation of enhanced excitatory activity in the hippocampal samples obtained from patients with TLE [19,21]. Activation of NMDA receptors leads to increased intracellular calcium ion levels which subsequently triggers activation of more of p38 kinase and/or protein kinase C leading to increased phosphorylation of cPLA2 [13,14,22].
A primary cilium in oligodendrocytes: a fine structure signal of repairs in thalamic Osmotic Demyelination Syndrome (ODS)
Published in Ultrastructural Pathology, 2021
Jacques Gilloteaux, Joanna Bouchat, Valery Bielarz, Jean-Pierre Brion, Charles Nicaise
These cells appeared with some changed topology. The cytoplasm electron density is preserved as in the NN cells. In the example illustrated in Figure 6A,B, the nucleus distorted profile ultrastructure was somewhat elongated but revealed a compact, segregated nucleolus. Indeed, its components, i.e. the dense fibrillar component compacted as a thick band is prominently distinguished and tend to separate from the granular accumulated cloud or spread of ribonucleoproteins that reached the peripheral layers of heterochromatin, decorating the inner nuclear leaflet of the nucleus envelope. In the example taken in Fig 6B, an adjacent, contacted neuron cell body maintained a large Golgi apparatus while the adjacent surrounding neuropil displayed some swollen myelinated axons and other neurite’s extensions. The electron-dense, shrunk oligodendrocytes displayed junctional contacts with astrocytes along with, in many samples examined, peculiar tiny or small intercellular parenchymal rifts (Fig. 6A-B).