China 
Africa 
Explore chapters and articles related to this topic
Central nervous system
Published in A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha, Clark’s Procedures in Diagnostic Imaging: A System-Based Approach, 2020
A Stewart Whitley, Jan Dodgeon, Angela Meadows, Jane Cullingworth, Ken Holmes, Marcus Jackson, Graham Hoadley, Randeep Kumar Kulshrestha
The lateral ventricles are roughly 6 cm long and lie in the cerebral hemispheres either side of the midline below the corpus callosum. Each comprises an anterior horn, posterior horn and temporal horn situated in the frontal lobe, occipital lobe and temporal lobes of the brain, respectively. In the posterior part of the anterior horn is the interventricular foramen, which joins the two ventricles and communicates inferiorly to open into the third ventricle through the foramen of Monro. The single third ventricle is a narrow midline structure situated between the two thalami. The floor is formed by the hypothalamus and an anterior projection forms the infundibular recess of the pituitary gland. It communicates posteriorly and inferiorly through the aqueduct of Sylvius to the fourth ventricle.
Mechanobiology in Health and Disease in the Central Nervous System
Published in Jiro Nagatomi, Eno Essien Ebong, Mechanobiology Handbook, 2018
Theresa A. Ulrich, Sanjay Kumar
The mechanical properties of the ECM can direct a wide range of cellular properties, including cell shape and cytoarchitecture [33–35], motility [36,37], matrix remodeling [38], differentiation [39–42], and the extension of functional cellular projections [43–46]. As the human brain develops, billions of cells are generated in the proliferative tissues lining the lateral ventricles of the brain. These cells migrate throughout the developing CNS, differentiate into neurons or glial cells, and establish a diverse array of organized structures with distinctive shapes and intricate internal architecture [47]. Neurogenesis continues, albeit in a much more limited way, into adulthood through the self-renewal and differentiation of adult neural stem cells (aNSCs) found within the hippocampus and subventricular zone [48]. The mechanosensitivity of aNSCs was recently explored by Saha et al., who demonstrated that the differentiation and self-renewal of aNSCs can be modulated by controlling the mechanical stiffness of the surrounding microenvironment [42]. In particular, culturing aNSCs on the surface of soft polymeric substrates with stiffnesses close to living brain tissue (∼100–500 Pa) favored differentiation into neurons, whereas culturing aNSCs on polymeric substrates with identical surface chemistry but much greater mechanical rigidity (∼1–10 kPa) favored differentiation into glial cell types. The latter finding raises the intriguing possibility that tissue stiffening may play an instructive role in glial scar formation rather than merely serving as a passive consequence of the process. This mechanosensitivity, coupled with the mechanical heterogeneity present throughout the normal and diseased brain, lends support to the hypothesis that mechanical cues may be dynamically involved in CNS development, in the maintenance of homeostasis, and in the development of disease.
Introduction
Published in Narayan Panigrahi, Saraju P. Mohanty, Brain Computer Interface, 2022
Narayan Panigrahi, Saraju P. Mohanty
There are two ventricles deep within the cerebral hemispheres called the lateral ventricles. They both connect with the third ventricle through a separate opening called the foramen of Monro. The third ventricle connects with the fourth ventricle through a long, narrow tube called the aqueduct of Sylvius. From the fourth ventricle, CSF flows into the subarachnoid space where it bathes and cushions the brain. CSF is recycled (or absorbed) by special structures in the superior sagittal sinus called arachnoid villi.
Computational modeling and simulation of stenosis of the cerebral aqueduct due to brain tumor
Published in Engineering Applications of Computational Fluid Mechanics, 2022
Uzair Ul Haq, Ali Ahmed, Zartasha Mustansar, Arslan Shaukat, Sasa Cukovic, Faizan Nadeem, Saadia Talay, M. Junaid Iqbal Khan, Lee Margetts
Figure 8(b) pertains to a tumor-specific case, where the pressure field is reported for a stenosed CA. In this case, a higher pressure in the lateral ventricles is observed owing to decreased outflow towards the fourth ventricle. The maximum pressure of 5.4 Pa is found in the lateral ventricles, with a pressure drop of 0.8 Pa in the third ventricle. The pressures in the CA present a unique case. A stenosed duct is practically a duct that is squeezed to a point where there is no outflow. Hence, beyond that point no fluid enters, which makes the pressure in that section drop below the surrounding pressures. This confirms that under a stenosed CA, the pressure in the CA and the fourth ventricle drops significantly, and the pressure in the lateral ventricles increases, indicating distension of the lateral ventricles.
Regional strain response of an anatomically accurate nonhuman primate finite element brain model under frontal impact
Published in Traffic Injury Prevention, 2022
Tyler F. Rooks, Valeta Carol Chancey, Jamie Baisden, Narayan Yoganandan
Additional granularity in anatomical structures was obtained from the NeuroMaps anatomical atlas of the rhesus macaque (Rohlfing et al. 2012). The NeuroMaps atlas includes the cortical and subcortical anatomy of the brain (e.g., gray and white matter, thalamus, basal ganglia, corpus callosum, and other components). The atlas and associated anatomical label information were imported into a 3DSlicer and STL files were created for each structure. Subsequent review of the anatomical structures was conducted by a practicing clinical neurosurgeon to group multiple anatomical components from the atlas into larger regions of interest. For comparisons with current and developmental human brain models, the anatomical regions of interest for the NHP model included the gray and white matter for the cerebrum, cerebellum, thalamus, pallidum, midbrain, hippocampus, corpus callosum, basal ganglia, brain stem, and third, fourth, and lateral ventricles (Rooks et al. 2021). The STL files defining the anatomical region of interest were subsequently used to identify elements in the left hemisphere of the global mesh belonging to each region using a custom MATLAB (r2021a; mathworks.com) algorithm (MATLAB 2022). The completed left hemisphere was mirrored about the midsagittal plane to create a symmetric model. Finally, the falx, tentorium, meninges (pia arachnoid, subarachnoid, and dura), and a rigid skull were added using shell elements. The material properties used in the present model were based in the latest isotropic Global Human Body Models Consortium model (Mao et al. 2013).
Consequences of space radiation on the brain and cardiovascular system
Published in Journal of Environmental Science and Health, Part C, 2021
Catherine M. Davis, Antiño R. Allen, Dawn E. Bowles
The hippocampal formation undergoes structural changes throughout the human lifespan. It is capable of dramatic reorganization, enabling environmental stimuli to impose functional and structural changes on the brain.7 The plasticity of neuronal connections functions through the generation of new neurons and synapses, which enables the brain to store memories.8 Neurogenesis is defined as the series of developmental steps that lead from the division of a neural stem or progenitor cell to a mature, functionally integrated neuron.9 The generation of new neurons from neural stem cells occurs in only two areas of the adult brain: the subventricular zone (SVZ) of the lateral ventricles and the subgranular zone (SGZ) of the DG in the hippocampus.7 In mammals, precursor cell proliferation occurs in the SGZ throughout life,10,11 resulting in newly born cells that are capable of migrating into the dentate granule cell layer.11 Newborn granule cells pass through several developmental steps, from a dividing progenitor to a mature granule cell that is indistinguishable from granule cells born during embryonic development.12 They develop granule cell morphology, then become functionally integrated into the local circuitry13 and have action potentials and functional synaptic inputs14 about 4 weeks after division.