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Aging Jun 2021Gamma H2A histone family member X (γH2AX) is a molecular marker of aging and disease. However, radiosensitivity of the different brain cells, including neurons, glial...
Gamma H2A histone family member X (γH2AX) is a molecular marker of aging and disease. However, radiosensitivity of the different brain cells, including neurons, glial cells, cells in cerebrovascular system, epithelial cells in pia mater, ependymal cells lining the ventricles of the brain in immature animals at different postnatal days remains unknown. Whether radiation-induced γH2AX foci in immature brain persist in adult animals still needs to be investigated. Hence, using a mouse model, we showed an extensive postnatal age-dependent induction of γH2AX foci in different brain regions at 1 day after whole body gamma irradiation with 5Gy at postnatal day 3 (P3), P10 and P21. P3 mouse brain epithelial cells in pia mater, glial cells in white matter and cells in cerebrovascular system were more radiosensitive at one day after radiation exposure than those from P10 and P21 mice. Persistent DNA damage foci (PDDF) were consistently demonstrated in the brain at 120 days and 15 months after irradiation at P3, P10 and P21, and these mice had shortened lifespan compared to the age-matched control. Our results suggest that early life irradiation-induced PDDF at later stages of animal life may be related to the brain aging and shortened life expectancy of irradiated animals.
Topics: Animals; Animals, Newborn; Dentate Gyrus; Gamma Rays; Histones; Mice; Survival Analysis; Time Factors
PubMed: 34162763
DOI: 10.18632/aging.203202 -
Fluids and Barriers of the CNS Jun 2019Periarterial spaces (PASs) are annular channels that surround arteries in the brain and contain cerebrospinal fluid (CSF): a flow of CSF in these channels is thought to...
BACKGROUND
Periarterial spaces (PASs) are annular channels that surround arteries in the brain and contain cerebrospinal fluid (CSF): a flow of CSF in these channels is thought to be an important part of the brain's system for clearing metabolic wastes. In vivo observations reveal that they are not concentric, circular annuli, however: the outer boundaries are often oblate, and the arteries that form the inner boundaries are often offset from the central axis.
METHODS
We model PAS cross-sections as circles surrounded by ellipses and vary the radii of the circles, major and minor axes of the ellipses, and two-dimensional eccentricities of the circles with respect to the ellipses. For each shape, we solve the governing Navier-Stokes equation to determine the velocity profile for steady laminar flow and then compute the corresponding hydraulic resistance.
RESULTS
We find that the observed shapes of PASs have lower hydraulic resistance than concentric, circular annuli of the same size, and therefore allow faster, more efficient flow of cerebrospinal fluid. We find that the minimum hydraulic resistance (and therefore maximum flow rate) for a given PAS cross-sectional area occurs when the ellipse is elongated and intersects the circle, dividing the PAS into two lobes, as is common around pial arteries. We also find that if both the inner and outer boundaries are nearly circular, the minimum hydraulic resistance occurs when the eccentricity is large, as is common around penetrating arteries.
CONCLUSIONS
The concentric circular annulus assumed in recent studies is not a good model of the shape of actual PASs observed in vivo, and it greatly overestimates the hydraulic resistance of the PAS. Our parameterization can be used to incorporate more realistic resistances into hydraulic network models of flow of cerebrospinal fluid in the brain. Our results demonstrate that actual shapes observed in vivo are nearly optimal, in the sense of offering the least hydraulic resistance. This optimization may well represent an evolutionary adaptation that maximizes clearance of metabolic waste from the brain.
Topics: Brain; Cerebral Arteries; Cerebrospinal Fluid; Glymphatic System; Humans; Models, Biological; Pia Mater
PubMed: 31217012
DOI: 10.1186/s12987-019-0140-y -
Brain and Behavior Aug 2019To analyze magnetic resonance imaging (MRI) findings and clinical diagnosis and treatment data relating to Angiostrongylus cantonensis infection to gain insight into the...
PURPOSE
To analyze magnetic resonance imaging (MRI) findings and clinical diagnosis and treatment data relating to Angiostrongylus cantonensis infection to gain insight into the disease.
MATERIALS AND METHODS
We retrospectively analyzed the epidemiology, clinical manifestations, diagnosis and treatment data, imaging manifestations, and outcomes of 27 patients who were clinically diagnosed with angiostrongyliasis and who underwent contrast-enhanced brain MRI.
RESULTS
Patients with A. cantonensis infection had a history of eating raw mollusks in the endemic area, and they mainly presented with dizziness and headache of varying degrees and vomiting (n = 7). Laboratory examinations revealed increased peripheral blood and cerebrospinal fluid (CSF) eosinophils, as well as increased CSF protein levels. Brain MRI findings mainly included eosinophilic meningitis, whereas linear or nodular enhancement of the pia mater was observed in enhanced T1-weighted and fluid-attenuated inversion recovery images, accompanied by encephalitis or vasculitis. Meningitis manifested as multiple, thickened flow voids around the meninges, and contrast-enhanced scans showed substantial enhancement in intracranial dilated and hyperplastic blood vessels.
CONCLUSION
The possibility of A. cantonensis infection should be considered in the effective use of albendazole or mebendazole as a treatment. Combining clinical history with laboratory examination is helpful in diagnosing A. cantonensis infection. A final definite diagnosis can be confirmed by detecting larvae in the CSF. The administration of corticosteroids during pathogen therapy can substantially reduce the therapeutic response.
Topics: Adult; Albendazole; Angiostrongylus cantonensis; Animals; Anthelmintics; Brain; China; Eosinophilia; Female; Humans; Magnetic Resonance Imaging; Male; Mebendazole; Meningitis; Retrospective Studies; Strongylida Infections
PubMed: 31313505
DOI: 10.1002/brb3.1361 -
NMC Case Report Journal 2022Leptomeningeal metastasis (LM) is a rare but devastating cancer complication. LM occurs when cancer spreads into the leptomeningeal layer or cerebrospinal fluid....
Leptomeningeal metastasis (LM) is a rare but devastating cancer complication. LM occurs when cancer spreads into the leptomeningeal layer or cerebrospinal fluid. Intracranial magnetic resonance (MR) images of LM are characterized by the diffuse enhancement of the leptomeninges along the cerebral sulci, cerebellar folia, and cranial nerves. Here, we report an extremely rare case of LM with an atypical MR image revealing tumor mass confinement to the arachnoid membrane. The case involves an 85-year-old man who was referred to our hospital with a three-day history of dysarthria. Radiological examination revealed a solid lesion with heterogeneous enhancement and a cystic component in the extra-axial region of the right parietal lobe. Upon subsequent general examination, multiple lung cancer metastases were suspected. The patient underwent gross total resection of the brain mass in the right parietal region. Although the tumor slightly adhered to the dura mater, it was sharply demarcated from the surrounding parenchyma and pia mater. Based on pathological examination, the tumor was diagnosed as small cell lung cancer metastasis. This metastatic brain tumor was exclusively confined to the arachnoid membrane and, except for a few blood vessels, the dura mater was not infiltrated by metastatic tumor cells. To our knowledge, this is the first reported case of LM in which the tumor mass is confined only to the arachnoid membrane. Thus, in cases with atypical MR images, a general examination considering the possibility of LM is important for prompt and accurate diagnosis.
PubMed: 36313794
DOI: 10.2176/jns-nmc.2022-0113 -
NeuroImage Aug 2020Determining the anatomical source of brain activity non-invasively measured from EEG or MEG sensors is challenging. In order to simplify the source localization problem,...
Determining the anatomical source of brain activity non-invasively measured from EEG or MEG sensors is challenging. In order to simplify the source localization problem, many techniques introduce the assumption that current sources lie on the cortical surface. Another common assumption is that this current flow is orthogonal to the cortical surface, thereby approximating the orientation of cortical columns. However, it is not clear which cortical surface to use to define the current source locations, and normal vectors computed from a single cortical surface may not be the best approximation to the orientation of cortical columns. We compared three different surface location priors and five different approaches for estimating dipole vector orientation, both in simulations and visual and motor evoked MEG responses. We show that models with source locations on the white matter surface and using methods based on establishing correspondences between white matter and pial cortical surfaces dramatically outperform models with source locations on the pial or combined pial/white surfaces and which use methods based on the geometry of a single cortical surface in fitting evoked visual and motor responses. These methods can be easily implemented and adopted in most M/EEG analysis pipelines, with the potential to significantly improve source localization of evoked responses.
Topics: Adult; Cerebral Cortex; Computer Simulation; Evoked Potentials, Motor; Evoked Potentials, Visual; Female; Functional Neuroimaging; Humans; Magnetoencephalography; Male; Pia Mater; White Matter; Young Adult
PubMed: 32305564
DOI: 10.1016/j.neuroimage.2020.116862 -
The Journal of International Medical... Jun 2020This study was performed to examine the clinical outcomes of epidural and intradural decompression for degenerative cervical myelopathy. (Observational Study)
Observational Study
OBJECTIVE
This study was performed to examine the clinical outcomes of epidural and intradural decompression for degenerative cervical myelopathy.
METHODS
The data for 13 patients who underwent epidural and intradural decompression for treatment of degenerative cervical myelopathy (study group) and 20 patients who underwent only cervical laminoplasty, fusion, and epidural decompression (historical control group) were retrospectively reviewed. The preoperative and postoperative neurological status was evaluated using the Japanese Orthopaedic Association (JOA) score.
RESULTS
All patients' neurological symptoms were significantly improved at the final follow-up. In the study group, the patients' mean preoperative JOA score was 8.07 ± 1.80, and the final score improved by 70.88% ± 21.18%. The blood loss and operation time were significantly greater in the study group than control group. The recovery time was shorter in the study group than control group. The improvement rate was not significantly different between the two groups.
CONCLUSIONS
A pia mater incision with separation of the arachnoid adhesion can significantly improve the cerebrospinal fluid flow and spinal blood flow in degenerative cervical myelopathy. Arachnoid adhesion can lead to intradural spinal scar compression. The surgical intervention described herein can achieve satisfactory neurological outcomes and shorten the recovery time.
Topics: Adult; Aged; Arachnoid; Cervical Vertebrae; Combined Modality Therapy; Decompression, Surgical; Epidural Space; Female; Follow-Up Studies; Humans; Laminoplasty; Male; Middle Aged; Pia Mater; Retrospective Studies; Spinal Cord Diseases; Spinal Fusion; Time Factors; Treatment Outcome
PubMed: 32527182
DOI: 10.1177/0300060520929585 -
Journal of Acupuncture and Meridian... Oct 2012The primo vascular system was recently observed in the central nervous systems of rabbits and rats, but no investigations in large animals have been reported. In the...
The primo vascular system was recently observed in the central nervous systems of rabbits and rats, but no investigations in large animals have been reported. In the present work we found a putative primo vascular system in the spinal cord of a pig. We obtained spines from four healthy pigs and fixed them with paraformaldehyde. The primo vessels were expected to lie in the subarachnoid space between the pia mater and the arachnoid mater. The composite of three membranes (the pia, the arachnoid, and the dura maters) wrapping the spinal cord was peeled off, isolated from the spine, and put on a slide glass. This composite was stained with 4',6'-Diamidino-2-phenylindole (DAPI) and phalloidin to show the nuclei and the f-actin, respectively, in the cells of the primo vessels. We observed eleven pieces of the putative primo vessels in the subarachnoid space of the spines at the thoracic spinal nerve area. They had the typical rod-shaped nuclei distributed in a broken line, and f-actin signals around nuclei. The lengths of the nuclei were 12-15 μm, and the thicknesses of the primo vessels were 8∼20 μm, which were consistent with other primo vessels that had been observed in the various organs of rabbits, rats, and mice. In addition, we observed branching of the primo vessels, which is again an expected result from previous works. In conclusion, a primo vessel was observed in the subarachnoid space of the spinal cord of a pig. This was the first observation of a primo vessel in a large animal, and the staining method used to observe the primo vessel in a fixed sample was newly developed in this work.
Topics: Acupuncture Points; Animals; Blood Vessels; Meridians; Spinal Cord; Subarachnoid Space; Swine
PubMed: 23040103
DOI: 10.1016/j.jams.2012.07.006 -
Molecular Brain Sep 2015Radial glial cells (RGCs), the instructive scaffolds for neuronal migration, are well characterized by their unique morphology and polarization; these cells extend...
BACKGROUND
Radial glial cells (RGCs), the instructive scaffolds for neuronal migration, are well characterized by their unique morphology and polarization; these cells extend elongated basal processes to the pial basement membrane (BM) and parallel to one another. However, little is known about the mechanisms that underlie the developmental regulation and maintenance of this unique morphology.
RESULTS
Here, by crossing Fstl1 (fl/fl) mice with an EIIa-Cre line, we identified a new role for the secreted glycoprotein Follistatin like-1 (FSTL1). The ablation of Fstl1 in both of its cortical expression domains, the ventricular zone (VZ) and the pia mater, resulted in RGC morphologic disruption; basal processes were not parallel to each other, and endfeet exhibited greater density and branching. However, Fstl1 deletion in only the VZ in the Emx1 (IREScre); Fstl1 (fl/fl) line did not affect RGC morphology, indicating that FSTL1 derived from the pia mater might be more important for RGC morphology. In addition, upper-layer projection neurons, not deeper-layer projection neurons, failed to reach their appropriate positions. We also found that BMP, AKT/PKB, Cdc42, GSK3β, integrin and reelin signals, which have previously been reported to regulate RGC development, were unchanged, indicating that Fstl1 may function through a unique mechanism.
CONCLUSIONS
In the present study, we identified a new role for FSTL1 in the development of radial glial scaffolds and the neuronal migration of upper-layer projection neurons. Our findings will improve understanding of the regulation of RGC development and neuronal migration.
Topics: Animals; Basement Membrane; Cell Polarity; Cell Shape; Cerebral Cortex; Cerebral Ventricles; Follistatin-Related Proteins; Gene Deletion; Mice; Neuroglia; Pia Mater; Reelin Protein
PubMed: 26382033
DOI: 10.1186/s13041-015-0144-8 -
The Journal of Experimental Medicine Nov 1898
PubMed: 19866888
DOI: 10.1084/jem.3.6.669 -
Neurologia Medico-chirurgica Apr 1989A case of porencephaly in a 33-year-old male is presented. The patient exhibited right hemiparesis and generalized seizures. Computed tomography and, subsequently,...
A case of porencephaly in a 33-year-old male is presented. The patient exhibited right hemiparesis and generalized seizures. Computed tomography and, subsequently, craniotomy revealed a cerebral defect in the left parietal lobe, which communicated with the lateral ventricle. On angiography and at surgery, the cortical branches of the middle cerebral artery were found to be stretched over the surface of the cyst. Histopathological examination showed the outer membrane of the cyst to consist of arachnoid, subarachnoid space, vessels, pia mater, and a layer of degenerative brain tissue on histology. The diagnosis of porencephaly and its differentiation from arachnoid cyst are discussed.
Topics: Adult; Arachnoid; Brain Diseases; Cerebral Angiography; Cerebral Ventricles; Cysts; Diagnosis, Differential; Humans; Male; Parietal Lobe; Tomography, X-Ray Computed
PubMed: 2478920
DOI: 10.2176/nmc.29.347