-
Journal of Orthopaedic Research :... Mar 2019This study was designed to investigate (i) extracellular matrix to specify adhesive substrates to human dura mater cell (hDMC); (ii) the alteration on adhesion-related...
This study was designed to investigate (i) extracellular matrix to specify adhesive substrates to human dura mater cell (hDMC); (ii) the alteration on adhesion-related molecules in hDMC; and (iii) secreted matrix metalloproteinases (MMPs) linked with extracellular matrix remodeling after exposure to inflammation. The hDMC was cultured from human dura mater tissue, and the studies were performed with hDMC after co-culturing with macrophage like THP-1 cells (Mϕ). The adhesion of co-cultured hDMC through collagen I increased 6.4-fold and through collagen IV increased 5.0-fold compared with the adhesion of naïve cells (p < 0.001). Integrin subtype α β expression was increased 6.3-fold (p < 0.001) and α expression was decreased 2.0-fold (p < 0.001) in the co-cultured cells compared with the naïve cells. Co-culturing induced significant increases in MMP-1 (13.9-fold, p < 0.01), MMP-3 (7.6-fold, p < 0.01), and VEGF (VEGF: 3.8-fold, p < 0.05) expression and decreases in MMP-9 (0.1-fold, p < 0.01) compared with the sum of naïve hDMC and Mϕ values. Increased hDMC adhesion under inflammatory conditions is caused by an increased cellular affinity for collagen I and IV mediated by increased hDMC levels of integrin subtype α β and environmental MMP-1, -3 and decreased MMP-9. Selective integrin subtype α β inhibition assay showed 37.8% and 35.7% reduction in adhesion of co-cultured hDMC to collagen I (p < 0.001) and IV (p = 0.057), respectively. The present study provides insight into the pathological conditions related to dura mater adhesion in inflammation. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 9999:1-11, 2019.
Topics: Adult; Aged; Cell Adhesion; Coculture Techniques; Collagen Type I; Collagen Type IV; Dura Mater; Extracellular Matrix; Female; Humans; Inflammation; Integrin alpha2beta1; Male; Matrix Metalloproteinases; Middle Aged; Primary Cell Culture; THP-1 Cells
PubMed: 30561137
DOI: 10.1002/jor.24207 -
Journal of Biomedical Materials... Oct 2014Intervertebral total disc replacements (TDR) are used in the treatment of degenerative spinal disc disease. There are, however, concerns that they may be subject to...
Intervertebral total disc replacements (TDR) are used in the treatment of degenerative spinal disc disease. There are, however, concerns that they may be subject to long-term failure due to wear. The adverse effects of TDR wear have the potential to manifest in the dura mater and surrounding tissues. The aim of this study was to investigate the physiological structure of the dura mater, isolate the resident dural epithelial and stromal cells and analyse the capacity of these cells to internalise model polymer particles. The porcine dura mater was a collagen-rich structure encompassing regularly arranged fibroblastic cells within an outermost epithelial cell layer. The isolated dural epithelial cells had endothelial cell characteristics (positive for von Willebrand factor, CD31, E-cadherin and desmoplakin) and barrier functionality whereas the fibroblastic cells were positive for collagen I and III, tenascin and actin. The capacity of the dural cells to take up model particles was dependent on particle size. Nanometer sized particles readily penetrated both types of cells. However, dural fibroblasts engulfed micron-sized particles at a much higher rate than dural epithelial cells. The study suggested that dural epithelial cells may offer some barrier to the penetration of micron-sized particles but not nanometer sized particles.
Topics: Animals; Dura Mater; Epithelial Cells; Fibroblasts; Nanoparticles; Particle Size; Swine; Total Disc Replacement
PubMed: 24604838
DOI: 10.1002/jbm.b.33129 -
Fluids and Barriers of the CNS Mar 2023Despite greatly renewed interest concerning meningeal lymphatic function over recent years, the lymphatic structures of human dura mater have been less characterized....
BACKGROUND
Despite greatly renewed interest concerning meningeal lymphatic function over recent years, the lymphatic structures of human dura mater have been less characterized. The available information derives exclusively from autopsy specimens. This study addressed methodological aspects of immunohistochemistry for visualization and characterization of lymphatic vessels in the dura of patients.
METHODS
Dura biopsies were obtained from the right frontal region of the patients with idiopathic normal pressure hydrocephalus (iNPH) who underwent shunt surgery as part of treatment. The dura specimens were prepared using three different methods: Paraformaldehyde (PFA) 4% (Method #1), paraformaldehyde (PFA) 0.5% (Method #2), and freeze-fixation (Method #3). They were further examined with immunohistochemistry using the lymphatic cell marker lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1), and as validation marker we used podoplanin (PDPN).
RESULTS
The study included 30 iNPH patients who underwent shunt surgery. The dura specimens were obtained average 16.1 ± 4.5 mm lateral to the superior sagittal sinus in the right frontal region (about 12 cm posterior to glabella). While lymphatic structures were seen in 0/7 patients using Method #1, it was found in 4/6 subjects (67%) with Method #2, while in 16/17 subjects (94%) using Method #3. To this end, we characterized three types of meningeal lymphatic vessels: (1) Lymphatic vessels in intimate contact with blood vessels. (2) Lymphatic vessels without nearby blood vessels. (3) Clusters of LYVE-1-expressing cells interspersed with blood vessels. In general, highest density of lymphatic vessels were observed towards the arachnoid membrane rather than towards the skull.
CONCLUSIONS
The visualization of meningeal lymphatic vessels in humans seems to be highly sensitive to the tissue processing method. Our observations disclosed most abundant lymphatic vessels towards the arachnoid membrane, and were seen either in close association with blood vessels or remote from blood vessels.
Topics: Humans; Lymphatic Vessels; Dura Mater; Meninges; Immunohistochemistry
PubMed: 36978127
DOI: 10.1186/s12987-023-00426-3 -
Surgical and Radiologic Anatomy : SRA Jun 2022Few reports have been published regarding the microanatomy of the dura mater located at the craniovertebral junction (CVJ). In clinic, the precise microanatomy of the...
PURPOSE
Few reports have been published regarding the microanatomy of the dura mater located at the craniovertebral junction (CVJ). In clinic, the precise microanatomy of the CVJ dura mater would be taken into account, for reducing surgical complications and ineffective surgical outcomes. The main objective of the present investigation was to further elucidate the fiber composition and sources of the cervical spinal dura mater.
METHODS
The formalin-fixed adult head and neck specimens (n = 21) were obtained and P45 plastinated section method was utilized for the present study. The fibers of the upper cervical spinal dura mater (SDM) were examined in the P45 sagittal sections in the CVJ area. All photographic documentation was performed via a Canon EOS 7D Mark camera.
RESULTS
The posterior wall of the SDM sac at CVJ was found to be composed of stratified fibers, which are derived from three sources: the cerebral dura mater, the occipital periosteum, and the myodural bridge (MDB). The proper layer of the cerebral dura mater passes over the brim of the foramen magnum and enters the vertebral canal to form the inner layer of the SDM, and the fibers originating from the periosteum of the brim of the foramen magnum form the middle layer. The fibers of the MDB are inserted into the SDM and form its outer layer. It was found that the total number of fibers from each origin varied in humans.
CONCLUSION
At the CVJ, the posterior wall of the SDM is a multi-layered structure composed of three different originated fibers. The cerebral dura mater, the periosteum located at the brim of the foramen magnum, and MDB contribute to the formation of the SDM. The present study would be beneficial to the choice of surgical approach at the CVJ and the protection of the SDB.
Topics: Cervical Vertebrae; Dura Mater; Humans; Neck; Neck Muscles; Plastination
PubMed: 35715572
DOI: 10.1007/s00276-022-02962-3 -
Anatomical Record (Hoboken, N.J. : 2007) Oct 2016The myodural bridge was proposed initially in 1995. The myodural bridge is a connective tissue bridge that connects a pair of deep muscles at the suboccipital region to...
The myodural bridge was proposed initially in 1995. The myodural bridge is a connective tissue bridge that connects a pair of deep muscles at the suboccipital region to the dura mater. There have been numerous studies concerning the morphology and function of the myodural bridge. To determine whether a myodural bridge exists in reptiles, six Siamese crocodiles were investigated using gross anatomy dissection and P45 sheet plastination technologies. As a result, we demonstrated that the posterior occipital muscles of the Siamese crocodile are directly or indirectly connected to the proatlas, atlas, and intermembrane between them. Multiple trabeculae existing in the posterior epidural space extended from the ventral surface of the proatlas, atlas, and intermembrane between them to the dorsal surface of the spinal dura mater. This study showed that the posterior occipital muscle in the suboccipital region of the Siamese crocodile is connected to the spinal dura mater through the proatlas, atlas, and the trabeculae. In conclusion, a myodural bridge-like structure exists in reptiles. This connection may act as a pump to provide cerebrospinal fluid (CSF) circulation at the occipitocervical junction. We hypothesize that a physiologic role of the Siamese crocodile's myodural bridge may be analogous to the human myodural bridge. Anat Rec, 299:1402-1408, 2016. © 2016 Wiley Periodicals, Inc.
Topics: Alligators and Crocodiles; Animals; Cervical Atlas; Dissection; Dura Mater; Neck; Neck Muscles
PubMed: 27507762
DOI: 10.1002/ar.23445 -
Annals of Neurology Mar 2018Cortical spreading depression (CSD) has long been implicated in migraine attacks with aura. The process by which CSD, a cortical event that occurs within the blood-brain...
OBJECTIVE
Cortical spreading depression (CSD) has long been implicated in migraine attacks with aura. The process by which CSD, a cortical event that occurs within the blood-brain barrier (BBB), results in nociceptor activation outside the BBB is likely mediated by multiple molecules and cells. The objective of this study was to determine whether CSD activates immune cells inside the BBB (pia), outside the BBB (dura), or in both, and if so, when.
METHODS
Investigating cellular events in the meninges shortly after CSD, we used in vivo two-photon imaging to identify changes in macrophages and dendritic cells (DCs) that reside in the pia, arachnoid, and dura and their anatomical relationship to TRPV1 axons.
RESULTS
We found that activated meningeal macrophages retract their processes and become circular, and that activated meningeal DCs stop migrating. We found that CSD activates pial macrophages instantaneously, pial, subarachnoid, and dural DCs 6-12 minutes later, and dural macrophages 20 minutes later. Dural macrophages and DCs can appear in close proximity to TRPV1-positive axons.
INTERPRETATION
The findings suggest that activation of pial macrophages may be more relevant to cases where aura and migraine begin simultaneously, that activation of dural macrophages may be more relevant to cases where headache begins 20 to 30 minutes after aura, and that activation of dural macrophages may be mediated by activation of migratory DCs in the subarachnoid space and dura. The anatomical relationship between TRPV1-positive meningeal nociceptors, and dural macrophages and DCs supports a role for these immune cells in the modulation of head pain. Ann Neurol 2018;83:508-521.
Topics: Animals; Cortical Spreading Depression; Dendritic Cells; Dura Mater; Female; Macrophages; Male; Mice; Mice, Inbred C57BL; Mice, Transgenic; Pia Mater; TRPV Cation Channels
PubMed: 29394508
DOI: 10.1002/ana.25169 -
World Neurosurgery Feb 2018The exact location of a hematoma in relation to the pachymeninges contributes to typical radiographic presentations. However, because of the complexity of hematoma... (Review)
Review
BACKGROUND
The exact location of a hematoma in relation to the pachymeninges contributes to typical radiographic presentations. However, because of the complexity of hematoma evolution and neomembrane formation, an unexpected intraoperative finding can lead to a change of surgical strategy. In addition, the concentration of hemoglobin and its degradation products, the integrity of red blood cells, and the infiltration of fibroblasts, polymorphonuclear neutrophils, and macrophages are factors that affect the imaging characteristics on computed tomography and magnetic resonance imaging as the hematoma ages.
CASE DESCRIPTION
An interdural hematoma (IDH)-a hemorrhage that splits the periosteal dura mater from the meningeal dura mater-is an extremely rare occurrence, and the diagnosis requires confirmation by surgical or pathologic findings. By presenting a case of an IDH that was misdiagnosed as a chronic subdural hematoma before surgery, and reviewing the literature, we propose the radiologic characteristics of presenting both dural border sign and dural beak sign on magnetic resonance imaging as a specific indicator for IDH preoperatively.
CONCLUSIONS
A careful evaluation of cerebral expansion before membranectomy was mandatory intraoperatively. For IDH, wide inner membranectomy (i.e., excision of meningeal dura mater) should not be necessary. An IDH should be considered as a distinct disease category when evaluating an extra-axial hematoma despite its rarity, because the characters of radiologic, histopathologic findings are different. In addition, surgical strategy varies for epidural or subdural hematoma in different hematoma stages.
Topics: Accidental Falls; Aged, 80 and over; Craniotomy; Diagnosis, Differential; Dura Mater; Hematoma; Humans; Intracranial Hemorrhage, Traumatic; Magnetic Resonance Imaging; Male
PubMed: 29155345
DOI: 10.1016/j.wneu.2017.11.040 -
Acta Neurochirurgica Oct 2022IgG4-related hypertrophic pachymeningitis is a rare fibroinflammatory disorder that may cause localized or diffused thickening of the dura mater. Misinterpretations of...
OBJECTIVE
IgG4-related hypertrophic pachymeningitis is a rare fibroinflammatory disorder that may cause localized or diffused thickening of the dura mater. Misinterpretations of the clinical and imaging findings are common. Clinical manifestations depend on the location of the inflammatory lesion and on compression of neural structures leading to functional deficits. A dural biopsy is commonly needed for a definitive diagnosis. Immunomodulatory therapy is considered the therapy of choice.
METHODS
Four patients with IgG4-related hypertrophic pachymeningitis were identified over a 5-year period. Patient-related characteristics including age, preoperative workup, signs and symptoms of patients, and diagnostic procedures were evaluated. Furthermore, the surgical treatment and 5-year follow-up outcomes were analyzed.
RESULTS
There were two adults and two adolescents (mean age 32 years; range 15 to 67 years). Two patients were male, and two were female. No history of disease was known in any of the patients. Clinical symptoms were epilepsy (n = 2), ataxia and nausea (n = 1), and facial nerve palsy (n = 1). MR imaging studies showed contrast enhancing lesions in the temporal region in two patients, and in the cerebellar region in the other two patients. Subtotal resection was performed in two instances and a biopsy via a suboccipital retrosigmoid approach was obtained in the other two patients. Histochemical and immunohistochemical investigations revealed an IgG 4 disease in all of these patients. Immunomodulatorry therapy led to clinical stability during follow-up of 5 years in all four cases.
CONCLUSION
The diagnosis of IgG4-related hypertrophic pachymeningitis is challenging, but is of great relevance as treatment differs significantly from other forms of pachymeningitis and a specific therapeutic approach may avoid long-term neurological complications. Our series contributes to a better clinical characterization of this rare disease.
Topics: Adolescent; Adult; Dura Mater; Female; Humans; Hypertrophy; Immunoglobulin G; Magnetic Resonance Imaging; Male; Meningitis; Neoplasms
PubMed: 35974231
DOI: 10.1007/s00701-022-05340-5 -
Current Eye Research Jul 2020We aimed to characterize the connective tissue microanatomy, elastin abundance, and fiber orientation in the human optic nerve sheath, also known as the optic nerve dura...
PURPOSE/AIM
We aimed to characterize the connective tissue microanatomy, elastin abundance, and fiber orientation in the human optic nerve sheath, also known as the optic nerve dura mater, for correlation with its biomechanical properties.
MATERIALS AND METHODS
Seven whole human orbits aged 4-93 years, and five isolated human optic nerve sheaths aged 26-75 years were formalin fixed, paraffin embedded, coronally sectioned, stained by Masson trichrome and van Gieson's elastin methods, and analyzed quantitatively for elastin fiber abundance and orientation. Elastin area fraction was defined as area stained for elastin divided by total area.
RESULTS
While unilaminar in children, the adult ON sheath exhibited distinct inner and outer layers. Collagen was denser and more compact in the inner layer. Elastin area fraction was significantly greater at 6.0 ± 0.4% (standard error of mean) in the inner than outer layer at 3.6 ± 0.4% ( < 10). Elastin fibers had three predominant orientations: longitudinal, diagonal, and circumferential. Of circumferential fibers, 63 ± 4.7% were in the inner and 37 ± 4.7% in the outer layer ( < 10). Longitudinal and diagonal fibers were uniformly distributed in both layers. Elastin density and sheath thickness increased significantly with age ( < .01).
CONCLUSIONS
The adult human optic nerve sheath is bilaminar, with each layer containing elastin fibers oriented in multiple directions consistent with isotropic properties. Differences in laminar elastin density and orientation may reflect greater tensile loading in the inner than in the outer layer.
Topics: Adult; Aged; Aged, 80 and over; Biomechanical Phenomena; Child, Preschool; Dura Mater; Elastic Tissue; Elastin; Humans; Middle Aged; Optic Nerve
PubMed: 32155090
DOI: 10.1080/02713683.2020.1739314 -
The Journal of International Medical... Mar 2020This study was performed to evaluate a new type of autologous muscle tamponade to repair dura mater that has undergone dural defects to prevent cerebrospinal fluid...
OBJECTIVE
This study was performed to evaluate a new type of autologous muscle tamponade to repair dura mater that has undergone dural defects to prevent cerebrospinal fluid leakage or subcutaneous fluid accumulation.
METHODS
Three hundred thirty-two patients who underwent retrosigmoid craniotomy were selected and divided into two groups: bone window craniotomy and bone flap craniotomy. Each group was further divided into two groups: artificial dura repair and autologous muscle repair. We then analysed the incidence of postoperative cerebrospinal fluid leakage or subcutaneous fluid accumulation and compared the effects of the two repair methods.
RESULTS
For all patients, autologous muscle repair of the dura mater had a lower incidence of cerebrospinal fluid leakage than artificial dura mater repair, especially in patients with craniotomy.
CONCLUSIONS
Subdural craniotomy of the bone window is more effective than conventional methods in preventing cerebrospinal fluid leakage.
Topics: Cerebrospinal Fluid Leak; Craniotomy; Dura Mater; Female; Humans; Male; Middle Aged; Muscles; Subdural Space; Surgical Flaps; Wound Healing
PubMed: 32223659
DOI: 10.1177/0300060520910299