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PloS One 2017Recent studies have identified that the myodural bridge (MDB) between the rectus capitis posterior minor (RCPmi) and the cervical spinal dura mater in the posterior...
Recent studies have identified that the myodural bridge (MDB) between the rectus capitis posterior minor (RCPmi) and the cervical spinal dura mater in the posterior atlanto-occipital interspace in humans. And it was supposed that the MDB may play essential physiological roles. As a result, the MDB is possibly a highly conserved structure in the evolution of mammals. However, there is little confirmative description about the existence of the MDB in marine mammals. The objective of this study was to explore the existence and the fiber property of the MDB in the Neophocaena phocaenoides. Six cadavers of the Neophocaena phocaenoides with formalin fixation were used in this study. One was used for head and neck CT scanning and three-dimensional (3D) reconstruction and suboccipital region dissection, two were for sectional observation by P45 plastinated sheets of head and neck, and three were for histological analysis of suboccipial structures. This is the first study to demonstrate the existence of the MDB in the aquatic mammals. The rectus capitis dorsal minor (RCDmi) originated from the inferior border of the occiput and inserted into the cervical spinal dura mater. At the ventral aspect of the RCDmi, the MDB directly extended through the posterior atlanto-occipital interspace and connected with the cervical spinal dura mater which was consisted of type Ⅰ collagen. In addition, the dorsal atlanto-occipital membrane was not found in the Neophocaena phocaenoides. The tendinous myodural bridge extended from the RCDmi to the spinal dura mater through the posterior atlanto-occipital interspace in the Neophocaena phocaenoides.
Topics: Animals; Cervical Vertebrae; Dura Mater; Head; Neck; Porpoises
PubMed: 28278181
DOI: 10.1371/journal.pone.0173630 -
Scientific Reports Jun 2021Meningiomas are benign tumors that are treated surgically. Local recurrence is likely if the dura is preserved, and en bloc tumor and dura resection (Simpson grade I) is...
Meningiomas are benign tumors that are treated surgically. Local recurrence is likely if the dura is preserved, and en bloc tumor and dura resection (Simpson grade I) is recommended. In some cases the dura is cauterized and preserved after tumor resection (Simpson grade II). The purpose of this study was performed to analyze clinical features and prognostic factors associated with spinal meningioma, and to identify the most effective surgical treatment. The subjects were 116 patients (22 males, 94 females) with spinal meningioma who underwent surgery at seven NSG centers between 1998 and 2018. Clinical data were collected from the NSG database. Pre- and postoperative neurological status was defined using the modified McCormick scale. The patients had a mean age of 61.2 ± 14.8 years (range 19-91 years) and mean symptom duration of 11.3 ± 14.7 months (range 1-93 months). Complete resection was achieved in 108 cases (94%), including 29 Simpson grade I and 79 Simpson grade II resections. The mean follow-up period was 84.8 ± 52.7 months. At the last follow-up, neurological function had improved in 73 patients (63%), was stable in 34 (29%), and had worsened in 9 (8%). Eight patients had recurrence, and recurrence rates did not differ significantly between Simpson grades I and II in initial surgery. Kaplan-Meier analysis of recurrence-free survival showed that Simpson grade III or IV, male, and dural tail sign were significant factors associated with recurrence (P < 0.05). In conclusion, Simpson I resection is anatomically favorable for spinal meningiomas. Younger male patients with a dural tail and a high-grade tumor require close follow-up. The tumor location and feasibility of surgery can affect the surgical morbidity in Simpson I or II resection. All patients should be carefully monitored for long-term outcomes, and we recommend lifelong surveillance after surgery.
Topics: Adult; Aged; Aged, 80 and over; Dura Mater; Female; Humans; Magnetic Resonance Imaging; Male; Meningioma; Middle Aged; Neoplasm Grading; Prognosis; Retrospective Studies; Spinal Neoplasms; Survival Analysis; Treatment Outcome
PubMed: 34079036
DOI: 10.1038/s41598-021-91225-z -
Annals of Clinical and Translational... Mar 2019Immunoglobulin (Ig)G4-related disease is a major cause of hypertrophic pachymeningitis (HP), presenting as a progressive thickening of the dura mater. HP lacks an animal...
OBJECTIVE
Immunoglobulin (Ig)G4-related disease is a major cause of hypertrophic pachymeningitis (HP), presenting as a progressive thickening of the dura mater. HP lacks an animal model to determine its underlying mechanisms. We developed a suitable animal model for the treatment of HP.
METHODS
We longitudinally evaluated dura in mice with a mutation (Y136F) in the linker for activation of T cells (LAT), which induced type 2 T helper (Th2) cell proliferation and IgG1 (IgG4 human equivalent) overexpression. Mice were therapeutically administered daily oral irbesartan from 3 to 6 weeks of age. Human IgG4-related, anti-neutrophil cytoplasmic antibody-related, and idiopathic HP dura were also immunohistochemically examined.
RESULTS
LATY136F mice showing dural gadolinium enhancement on magnetic resonance imaging had massive infiltration of B220 B cells, IgG1 cells, CD138 plasma cells, CD3 T cells, F4/80 macrophages, and polymorphonuclear leukocytes in the dura at 3 weeks of age, followed by marked fibrotic thickening. In dural lesions, transforming growth factor (TGF)-1 was produced preferentially in B cells and macrophages while TGF-β receptor I (TGF- RI) was markedly upregulated on fibroblasts. Quantitative western blotting revealed significant upregulation of TGF-1, TGF- RI, and phosphorylated SMAD2/SMAD3 in dura of LATY136F mice aged 13 weeks. A similar upregulation of TGF- RI, SMAD2/SMAD3, and phosphorylated SMAD2/SMAD3 was present in autopsied dura of all three types of human HP. Irbesartan abolished dural inflammatory cell infiltration and fibrotic thickening in all treated LATY136F mice with reduced TGF-β1 and nonphosphorylated and phosphorylated SMAD2/SMAD3.
INTERPRETATION
TGF-1/SMAD2/SMAD3 pathway is critical in HP and is a potential novel therapeutic target.
Topics: Adaptor Proteins, Signal Transducing; Animals; Dura Mater; Fibrosis; Humans; Hypertrophy; Inflammation; Irbesartan; Membrane Proteins; Meningitis; Mice; Mice, Transgenic; Models, Animal; Phosphorylation; Signal Transduction; Smad2 Protein; Smad3 Protein; Transforming Growth Factor beta1
PubMed: 30911567
DOI: 10.1002/acn3.715 -
PeerJ 2023Chronic subdural hemorrhage (CSDH) refers to a hematoma with an envelope between the dura mater and the arachnoid membrane and is more common among the elderly. It was...
Chronic subdural hemorrhage (CSDH) refers to a hematoma with an envelope between the dura mater and the arachnoid membrane and is more common among the elderly. It was reported that the dura mater, which is highly vascularized with capillary beds, precapillary arterioles and postcapillary venules play an important role in the protection of the central nervous system (CNS). Numerous evidences suggests that peptides play an important role in neuroprotection of CNS. However, whether dura mater derived endogenous peptides participate in the pathogenesis of CSDH remains undetermined. In the current study, the peptidomic profiles were performed in human dura of CSDH (three patients) and the relative control group (three non-CSDH samples) by LC-MS (liquid chromatography-mass spectrometry). The results suggested that a total of 569 peptides were differentially expressed in the dura matter of CSDH compared with relative controls, including 217 up-regulated peptides and 352 down-regulated peptides. Gene Ontology (GO) analysis demonstrated that the precursor proteins of those differentially expressed peptides were involved in the various biological processes. Interestingly, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis suggested that NETs participated in the pathogenies of CSDH. Further investigate showed that H3Cit was significantly elevated in the dural and hematoma membranes of patients with CSDH compared to patients without CSDH. Taken together, our results showed the differentially expressed peptides in human dura mater of CSDH and demonstrated that NETs formation in the dural and hematoma membranes might be involved in the pathogenesis of CSDH. It is worth noting that pharmacological inhibition of NETs may have potential therapeutic implications for CSDH.
Topics: Humans; Aged; Extracellular Traps; Hematoma, Subdural, Chronic; Dura Mater; Peptides; Proteomics
PubMed: 38144176
DOI: 10.7717/peerj.16676 -
Journal of Musculoskeletal & Neuronal... Sep 2020The aim of this study is to review and discuss the literature on the utilization of magnetic resonance imaging (MRI) in investigating the structure and feasible function... (Review)
Review
The aim of this study is to review and discuss the literature on the utilization of magnetic resonance imaging (MRI) in investigating the structure and feasible function of the myodural bridge complex (MDBC) with relevant muscles, which will be useful to understand the function of the MDB. The myodural bridge (MDB) is a soft tissue connective bridge that provides a fascial continuity between the musculature/ligament and cervical spinal dura mater (SDM) in the suboccipital areas. All of these involved structures are referred to as the MDBC. It would transfer tensile forces effectively from involved suboccipital muscles/ligament to SDM during head movement. Despite present achievements, its anatomic and functional role is still unclear. MRI enables not only visualization of ligaments, musculature and spinal dura with conventional TW, TW and PDW imaging, but also functional evaluation of MDBC with relevant muscles, such as muscles' fatty infiltration, cross-sectional area changes and injuries. Though some functional MRI techniques have not been used for the MDBC with relevant muscles now, these techniques have great potential to better understand function of MDBC including its suspected clinical role. MRI is likely the most powerful tool to study MDBC and relevant muscles with only limited exploration so far.
Topics: Cervical Vertebrae; Connective Tissue; Dura Mater; Humans; Magnetic Resonance Imaging; Neck Muscles
PubMed: 32877974
DOI: No ID Found -
Annals of Palliative Medicine Sep 2022Intradural lumbar disc herniation (ILDH) is special type of lumbar disc herniation in which the lumbar nucleus pulposus prolapses and enters the dura mater. ILDHs... (Review)
Review
BACKGROUND
Intradural lumbar disc herniation (ILDH) is special type of lumbar disc herniation in which the lumbar nucleus pulposus prolapses and enters the dura mater. ILDHs comprise 0.04-0.33% of all herniated discs. In most cases, the diagnosis could not be confirmed preoperatively by identifying the typical features of ILDH in radiological evaluation. In the current report, we present a case of ILDH at lumbar 2/3 level and discuss the clinical presentations, typical imaging features, treatments, and outcomes.
CASE DESCRIPTION
We describe a rare case of ILDH. The patient was a 65-year-old man with pain in waist and back, and with bilateral radiating pain of lower extremities and fatigue for more than 2 weeks. Magnetic resonance imaging (MRI) revealed a large round, low-density mass at lumbar 2/3, which was easily mimicked as an intradural spinal tumor lesion. While enhanced MRI showed the typical rim enhancement sign and "Hawk beak" sign. Due to progressive decrease in muscle strength in both lower limbs, posterior microscopically assisted laminectomy, dural incision of the lumbar 2/3 was performed. Pathological examination revealed degenerated fibrous connective tissue and cartilage tissue. The patient's lower back pain and radiating pain and numbness of both legs improved remarkably postoperatively, and he became asymptomatic at 3 months and 1-year postoperatively.
CONCLUSIONS
ILDH is a rare intervertebral disc herniation in clinical practice. The pathogenesis of ILDH may be related to aseptic inflammatory edema, closely fixing of ventral dura and the posterior longitudinal ligament, repeated mechanical action and chemical corrosion. Typical rim enhancement sign, "Hawk beak" sign and "Y" sign are important features of MRI in diagnosing ILDH, and intraspinal gas is also helpful in computed tomography (CT) diagnosis of ILDH. Prompt microscopically assisted laminectomy, dura mater incision to remove the intradural disc, pedicle screw fixation regardless of fusion, surgical results are usually favorable. We also reviewed the literature and discussed the epidemiology, potential pathogenesis, diagnosis, treatment and poor prognostic factors of ILDH.
Topics: Aged; Dura Mater; Humans; Intervertebral Disc Displacement; Lumbar Vertebrae; Magnetic Resonance Imaging; Male; Pain; Spinal Neoplasms
PubMed: 36217628
DOI: 10.21037/apm-22-1017 -
Cells May 2022Monoclonal antibodies directed against the neuropeptide calcitonin gene-related peptide (CGRP) belong to a new generation of therapeutics that are effective in the...
Monoclonal antibodies directed against the neuropeptide calcitonin gene-related peptide (CGRP) belong to a new generation of therapeutics that are effective in the prevention of migraine. CGRP, a potent vasodilator, is strongly implicated in the pathophysiology of migraine, but its role remains to be fully elucidated. The hemisected rat head preparation and laser Doppler flowmetry were used to examine the effects on CGRP release from the dura mater and meningeal blood flow of the subcutaneously injected anti-CGRP monoclonal antibody fremanezumab at 30 mg/kg, when compared to an isotype control antibody. Some rats were administered glycerol trinitrate (GTN) intraperitoneally to produce a migraine-like sensitized state. When compared to the control antibody, the fremanezumab injection was followed by reduced basal and capsaicin-evoked CGRP release from day 3 up to 30 days. The difference was enhanced after 4 h of GTN application. The samples from the female rats showed a higher CGRP release compared to that of the males. The increases in meningeal blood flow induced by acrolein (100 µM) and capsaicin (100 nM) were reduced 13-20 days after the fremanezumab injection, and the direct vasoconstrictor effect of high capsaicin (10 µM) was intensified. In conclusion, fremanezumab lowers the CGRP release and lasts up to four weeks, thereby lowering the CGRP-dependent meningeal blood flow. The antibody may not only prevent the released CGRP from binding but may also influence the CGRP release stimulated by noxious agents relevant for the generation of migraine pain.
Topics: Animals; Antibodies, Monoclonal; Calcitonin Gene-Related Peptide; Capsaicin; Dura Mater; Female; Male; Migraine Disorders; Rats
PubMed: 35681463
DOI: 10.3390/cells11111768 -
Neurosurgical Review Jul 2010Many techniques are described to treat Chiari type I malformation. One of them is a splitting of the dura, removing its outer layer only to reduce the risks of...
Many techniques are described to treat Chiari type I malformation. One of them is a splitting of the dura, removing its outer layer only to reduce the risks of cerebrospinal fluid (CSF) leak. We try to show the effectiveness of this technique from histological and biomechanical observations of dura mater. Study was performed on 25 posterior fossa dura mater specimens from fresh human cadavers. Dural composition and architecture was assessed on 47 transversal and sagittal sections. Uniaxial mechanical tests were performed on 22 dural samples (15 entire, 7 split) to focus on the dural macroscopic mechanical behavior comparing entire and split samples and also to understand deformation mechanisms. We finally created a model of volume expansion after splitting. Dura mater was composed of predominant collagen fibers with a few elastin fibers, cranio-caudally orientated. The classical description of two distinct layers remained inconstant. Biomechanical tests showed a significant difference between entire dura, which presents an elastic fragile behavior, with a small domain where deformation is reversible with stress, and split dura, which presents an elasto-plastic behavior with a large domain of permanent strain and a lower stress level. From these experimental results, the model showed a volume increase of approximately 50% below the split area. We demonstrated the capability of the split dura mater to enlarge for suitable stress conditions and we quantified it by biomechanical tests and experimental model. Thus, dural splitting decompression seems to have a real biomechanical substrate to envision the efficacy of this Chiari type I malformation surgical technique.
Topics: Aged; Arnold-Chiari Malformation; Biomechanical Phenomena; Cadaver; Cranial Fossa, Posterior; Decompression, Surgical; Dura Mater; Female; Humans; Male; Microscopy, Electron, Scanning; Neurosurgical Procedures; Tensile Strength
PubMed: 20440557
DOI: 10.1007/s10143-010-0261-x -
PloS One 2018Borrelia burgdorferi, the causative agent of Lyme disease, is a vector-borne bacterial infection that is transmitted through the bite of an infected tick. If not treated...
Borrelia burgdorferi, the causative agent of Lyme disease, is a vector-borne bacterial infection that is transmitted through the bite of an infected tick. If not treated with antibiotics during the early stages of infection, disseminated infection can spread to the central nervous system (CNS). In non-human primates (NHPs) it has been demonstrated that the leptomeninges are among the tissues colonized by B. burgdorferi spirochetes. Although the NHP model parallels aspects of human borreliosis, a small rodent model would be ideal to study the trafficking of spirochetes and immune cells into the CNS. Here we show that during early and late disseminated infection, B. burgdorferi infects the meninges of intradermally infected mice, and is associated with concurrent increases in meningeal T cells. We found that the dura mater was consistently culture positive for spirochetes in transcardially perfused mice, independent of the strain of B. burgdorferi used. Within the dura mater, spirochetes were preferentially located in vascular regions, but were also present in perivascular, and extravascular regions, as late as 75 days post-infection. At the same end-point, we observed significant increases in the number of CD3+ T cells within the pia and dura mater, as compared to controls. Flow cytometric analysis of leukocytes isolated from the dura mater revealed that CD3+ cell populations were comprised of both CD4 and CD8 T cells. Overall, our data demonstrate that similarly to infection in peripheral tissues, spirochetes adhere to the dura mater during disseminated infection, and are associated with increases in the number of meningeal T cells. Collectively, our results demonstrate that there are aspects of B. burgdorferi meningeal infection that can be modelled in laboratory mice, suggesting that mice may be useful for elucidating mechanisms of meningeal pathogenesis by B. burgdorferi.
Topics: Animals; Bacterial Adhesion; Borrelia burgdorferi; CD4-Positive T-Lymphocytes; CD8-Positive T-Lymphocytes; Capillaries; Cell Movement; Disease Models, Animal; Dura Mater; Host-Pathogen Interactions; Humans; Injections, Intradermal; Lyme Disease; Male; Meninges; Mice; Mice, Inbred C3H
PubMed: 29723263
DOI: 10.1371/journal.pone.0196893 -
ENeuro May 2024High-density linear probes, such as Neuropixels, provide an unprecedented opportunity to understand how neural populations within specific laminar compartments...
High-density linear probes, such as Neuropixels, provide an unprecedented opportunity to understand how neural populations within specific laminar compartments contribute to behavior. Marmoset monkeys, unlike macaque monkeys, have a lissencephalic (smooth) cortex that enables recording perpendicular to the cortical surface, thus making them an ideal animal model for studying laminar computations. Here we present a method for acute Neuropixels recordings in the common marmoset (). The approach replaces the native dura with an artificial silicon-based dura that grants visual access to the cortical surface, which is helpful in avoiding blood vessels, ensures perpendicular penetrations, and could be used in conjunction with optical imaging or optogenetic techniques. The chamber housing the artificial dura is simple to maintain with minimal risk of infection and could be combined with semichronic microdrives and wireless recording hardware. This technique enables repeated acute penetrations over a period of several months. With occasional removal of tissue growth on the pial surface, recordings can be performed for a year or more. The approach is fully compatible with Neuropixels probes, enabling the recording of hundreds of single neurons distributed throughout the cortical column.
Topics: Animals; Callithrix; Dura Mater; Neurons; Male; Female; Electrodes, Implanted; Cerebral Cortex; Optogenetics
PubMed: 38658139
DOI: 10.1523/ENEURO.0544-23.2024