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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 -
International Journal of Surgery... Apr 2024Decompressive craniectomy, a surgery to remove part of the skull and open the dura mater, maybe an effective treatment for controlling intracranial hypertension. It...
BACKGROUND
Decompressive craniectomy, a surgery to remove part of the skull and open the dura mater, maybe an effective treatment for controlling intracranial hypertension. It remains great interest to elucidate whether decompressive craniectomy is beneficial to intracerebral hemorrhage patients who warrant clot removal to prevent intracranial hypertension.
METHODS
The trial was a prospective, pragmatic, controlled trial involving adult patients with intracerebral hemorrhage who were undergoing removal of hematoma. Intracerebral hemorrhage patients were randomly assigned at a 1:1 ratioto undergo clot removal with or without decompressive craniectomy under the monitoring of intracranial pressure. The primary outcome was the proportion of unfavorable functional outcome (modified Rankin Scale 3-6) at 3 months. Secondary outcomes included the mortality at 3 months and the occurrence of re-operation.
RESULTS
A total of 102 patients were assigned to the clot removal with decompressive craniectomy group and 102 to the clot removal group. Median hematoma volume was 54.0 mL (range 30-80 mL) and median preoperative Glasgow Coma Scale was 10 (range 5-15). At 3 months, 94 patients (92.2%) in clot removal with decompressive craniectomy group and 83 patients (81.4%) in the clot removal group had unfavorable functional outcome (P=0.023). Fourteen patients (13.7%) in the clot removal with decompressive craniectomy group died versus five patients (4.9%) in the clot removal group (P=0.030). The number of patients with re-operation was similar between the clot removal with decompressive craniectomy group and clot removal group (5.9% vs. 3.9%; P=0.517). Postoperative intracranial pressure values were not significantly different between two groups and the mean values were less than 20 mmHg.
CONCLUSIONS
Clot removal without decompressive craniectomy decreased the rate of modified Rankin Scale score of 3-6 and mortality in patients with intracerebral hemorrhage, compared with clot removal with decompressive craniectomy.
PubMed: 38640513
DOI: 10.1097/JS9.0000000000001466 -
Zhongguo Xiu Fu Chong Jian Wai Ke Za... Apr 2024To explore the therapeutic effect of basic fibroblast growth factor (bFGF) on spinal cord injury (SCI) in rats and the influence of Notch/signal transducer and activator...
[Therapeutic mechanism of basic fibroblast growth factor on spinal cord injury in rats based on the Notch/signal transducer and activator of transcription 3 signaling pathway].
OBJECTIVE
To explore the therapeutic effect of basic fibroblast growth factor (bFGF) on spinal cord injury (SCI) in rats and the influence of Notch/signal transducer and activator of transcription 3 (STAT3) signaling pathway.
METHODS
A total of 40 10-week-old male Sprague Dawley (SD) rats were selected to establish T -segment SCI model by a free falling object. Among them, 32 successful models were randomly divided into model group and bFGF group, with 16 in each group. Another 16 SD rats were selected as sham-operation group, with only T processes, dura mater, and spinal cord exposed. After modeling, the rats in bFGF group were intraperitoneally injected with 100 μg/kg bFGF (once a day for 28 days), and the rats in model group and sham-operation group were injected with normal saline in the same way. The survival of rats in each group were observed after modeling. Basso-Beattie-Bresnahan (BBB) scores were performed before modeling and at immediate, 14 days, and 28 days after modeling to evaluate the functional recovery of hind limbs. Then, the spinal cord tissue at the site of injury was taken at 28 days and stained with HE, Nissl, and propidium iodide (PI) to observe the pathological changes, neuronal survival (number of Nissl bodies) and apoptosis (number of PI red stained cells) of the spinal cord tissue; immunohistochemical staining and ELISA were used to detect the levels of astrocyte activation markers [glial fibrillary acidic protein (GFAP)] and inflammatory factors [interleukin 1β (IL-1β), tumor necrosis factor α (TNF-α), interferon γ (IFN-γ)] in tissues, respectively. Western blot was used to detect the expressions of Notch/STAT3 signaling pathway related proteins [Notch, STAT3, phosphoryl-STAT3 (p-STAT3), bone morphogenetic protein 2 (BMP-2)] in tissues.
RESULTS
All rats survived until the experiment was completed. At immediate after modeling, the BBB scores in model group and bFGF group significantly decreased when compared to sham-operation group ( <0.05). At 14 and 28 days after modeling, the BBB scores in model group significantly decreased when compared to sham-operation group ( <0.05); the bFGF group showed an increase compared to model group ( <0.05). Compared with before modeling, the BBB scores of model group and bFGF group decreased at immediate after modeling, and gradually increased at 14 and 28 days, the differences between different time points were significant ( <0.05). The structure of spinal cord tissue in sham-operation group was normal; in model group, there were more necrotic lesions in the spinal cord tissue and fewer Nissl bodies with normal structures; the number of necrotic lesions in the spinal cord tissue of the bFGF group significantly reduced compared to the model group, and some normally structured Nissl bodies were visible. Compared with sham-operation group, the number of Nissl bodies in spinal cord tissue significantly decreased, the number of PI red stained cells, GFAP, IL-1β, TNF-α, IFN-γ, Notch, p-STAT3 /STAT3, BMP-2 protein expression levels significantly increased in model group ( <0.05). The above indexes in bFGF group significantly improved when compared with model group ( <0.05).
CONCLUSION
bFGF can improve motor function and pathological injury repair of spinal cord tissue in SCI rats, improve neuronal survival, and inhibit neuronal apoptosis, excessive activation of astrocytes in spinal cord tissue and inflammatory response, the mechanism of which may be related to the decreased activity of Notch/STAT3 signaling pathway.
Topics: Rats; Male; Animals; Rats, Sprague-Dawley; Fibroblast Growth Factor 2; STAT3 Transcription Factor; Tumor Necrosis Factor-alpha; Spinal Cord Injuries; Spinal Cord; Signal Transduction
PubMed: 38632070
DOI: 10.7507/1002-1892.202312066 -
The Journal of International Medical... Apr 2024Rosai-Dorfman disease (RDD) is a rare non-Langerhans cell histiocytosis characterized by massive lymphadenopathy and systemic extranodal lesions. We present the case of... (Review)
Review
Rosai-Dorfman disease (RDD) is a rare non-Langerhans cell histiocytosis characterized by massive lymphadenopathy and systemic extranodal lesions. We present the case of a 28-year-old woman who presented with recurrent blurred vision in her right eye for 3 months. She developed blindness and atrophy in her left eye a decade prior to presentation. She subsequently developed headache, fever, and impaired mental status. Cranial magnetic resonance imaging indicated hypertrophic pachymeningitis (HP), and F-fluoro-2-deoxy-2-d-glucose (FDG) positron emission tomography/computed tomography revealed significant FDG uptake in the left dura mater. Autoimmune testing revealed elevated anti-nuclear, anti-SS-A, and anti-SS-B antibody levels. Incisional biopsy of the atrophic eyeball revealed RDD with marked polyclonal plasmacytosis. The patient was diagnosed with RDD accompanied by multisystem involvement, including Sjögren's syndrome (SS), panuveitis, and HP. Treatment with methylprednisolone for several weeks resulted in significant improvement. This is the first reported case of RDD presenting with SS in combination with panuveitis and HP. Although RDD is rarely diagnosed in young patients, interdisciplinary collaboration is essential to prevent a delayed diagnosis.
Topics: Humans; Female; Adult; Histiocytosis, Sinus; Sjogren's Syndrome; Fluorodeoxyglucose F18; Positron Emission Tomography Computed Tomography; Hypertrophy; Panuveitis
PubMed: 38629479
DOI: 10.1177/03000605241233141 -
Neurosurgical Review Apr 2024Chronic subdural hematoma (CSDH) is frequently met in neurosurgical practice and often need urgent surgical treatment in case of neurological deterioration. Different...
OBJECTIVE
Chronic subdural hematoma (CSDH) is frequently met in neurosurgical practice and often need urgent surgical treatment in case of neurological deterioration. Different surgical approaches to evacuate CSDH are described in the literature. In our experience, an external drainage system is crucial in order to avoid recurrences. We recently encountered a case of subcutaneous CSF collection after drainage removal. Thus, we developed a simple surgical technique to prevent postoperative CSF leak after subdural drainage system removal.
METHOD
We have developed a technique in which the periosteum is harvested during the surgery prior to the evacuation of the hemorrhage and fixed with sutures on the uncut dura mater opposite and laterally to the exit of the catheter exiting the dural hole caused by the passage of the Jackson-Pratt subdural drainage system. When the drainage catheter is removed, the flap, partially held by the sutures, falls over the hole avoiding CSF leakage. By using this technique, the small dural hole will be covered with the periosteum allowing for natural closure and wound healing hence preventing CSF leakage.
RESULTS
This technique was successfully employed in 21 patients who didn't develop postoperative CSF leakage following CSDH evacuation and removal of subdural drainage system.
CONCLUSION
In this technical note, we describe a safe dura closure technique that we developed to help reduce the risk of postoperative CSF leakage following subdural drainage removal, which can, however, also be applied in all surgeries in which a catheter is placed in the subdural space.
Topics: Humans; Hematoma, Subdural, Chronic; Drainage; Cerebrospinal Fluid Leak; Dura Mater; Postoperative Period
PubMed: 38625461
DOI: 10.1007/s10143-024-02412-1 -
Revista Espanola de Medicina Nuclear E... 2024
Topics: Humans; Female; Breast Neoplasms; Ossification, Heterotopic; Dura Mater; Magnetic Resonance Imaging; Middle Aged; Brain Neoplasms
PubMed: 38621477
DOI: 10.1016/j.remnie.2024.500001 -
BioRxiv : the Preprint Server For... Apr 2024Calvarial nerves, along with vasculature, influence skull formation during development and following injury, but it remains unclear how calvarial nerves are spatially...
Calvarial nerves, along with vasculature, influence skull formation during development and following injury, but it remains unclear how calvarial nerves are spatially distributed during postnatal growth and aging. Studying the spatial distribution of nerves in the skull remains challenging due to a lack of methods to image and quantify 3D structures in intact bone. To visualize calvarial 3D neurovascular architecture, we imaged nerves and endothelial cells with lightsheet microscopy. We employed machine-learning-based segmentation to facilitate high-resolution characterization from post-natal day 0 (P0) to Week 80 (80wk). We found that TUBB3+ nerve density decreased with aging with the frontal bone demonstrating earlier onset age-related nerve loss than the parietal bone. In addition, nerves in the periosteum and dura mater exhibited similar yet distinct temporal patterns of nerve growth and loss. While no difference was observed in TUBB3+ nerves during skeletal maturation (P0 → 12wk), we did observe an increase in the volume of unmyelinated nerves in the dura mater. Regarding calvarial vasculature, larger CD31Emcn vessel density increased with aging, while CD31Emcn vessel density was reduced. For all nerve markers studied, calvarial nerves maintained a preferential spatial association with CD31Emcn vessels that decreased with aging. Additionally, we used a model of Apert syndrome that demonstrates early coronal suture fusion to explore the impact of suture-related disease on neurovascular architecture. We identified a mild dysregulation of dural nerves and minor shifts in vessel populations. Collectively, this 3D, spatiotemporal characterization of calvarial nerves throughout the lifespan and provides new insights into age-induced neurovascular architecture.
PubMed: 38617372
DOI: 10.1101/2024.03.28.587299 -
Journal of Neuroradiology = Journal de... Jun 2024This study aimed to assess skull contents, brain appearance, and density on postmortem computed tomography in naturally mummified corpses.
INTRODUCTION
This study aimed to assess skull contents, brain appearance, and density on postmortem computed tomography in naturally mummified corpses.
MATERIAL AND METHODS
For this purpose, a retrospective multicentric study, including mummified corpses from two French centers (Brest and Nantes) and from the New Mexico Decedent Image Database (USA), was performed by analyzing postmortem computed tomography (PMCT) focused on the head and neck of partially or fully mummified corpses discovered between 2011 and 2022. The PMCT analysis provided data on the CT appearance of brains, allowing them to be classified into four different categories (desiccation, liquefaction, dura mater only (DMO), and absence), and to measure densities (HU) of the brain remains. In addition, data on postmortem intervals (PMI) from Nantes and Brest centers were collected and analyzed to test the link between brain densities and PMIs.
RESULTS
54 cases of naturally mummified corpses were included. The brains were classified as liquefied (56%), desiccated (17 %), DMO (20 %), and absent (7 %) based on their CT appearance. Dehydrated brains were significantly (p < 0.004) denser (median 102 HU, interquartile range (IQR) 41) than either liquefied brains (median 39.5 HU, IQR 9) or brains with DMO (median -25 HU, IQR 57). However, the density of brain remains was not significantly affected by where the bodies were found (p = 0,41). Analysis of PMI and brain densities was performed on 22 cases. The results showed that brain remains were significantly (p = 0.039) denser when they were found after a PMI of more than six months.
CONCLUSION
Brain desiccation was the aspect with the highest densities on PMCT, and for which we were able to highlight great preservation of anatomical structures observable in living organisms.
Topics: Humans; Tomography, X-Ray Computed; Retrospective Studies; Male; Skull; Female; Adult; Middle Aged; Brain; Mummies; Aged; Autopsy; Postmortem Changes; Aged, 80 and over; France
PubMed: 38588919
DOI: 10.1016/j.neurad.2024.04.001 -
Head & Neck Jun 2024Data from patients with post-ablative dural defects reconstructed using a free temporalis muscle fascia graft (FTFG) after resection of anterior or central skull base...
Free temporalis muscle fascia graft in dural reconstruction following surgical resection of intermediate and malignant skull base tumors: A 10-year experience from a single center.
BACKGROUND
Data from patients with post-ablative dural defects reconstructed using a free temporalis muscle fascia graft (FTFG) after resection of anterior or central skull base tumors were retrospectively analyzed.
METHODS
The primary predictor and outcome variables were the reconstructive methods for dural repair and postoperative cerebrospinal fluid (CSF) leakage rate, respectively.
RESULTS
Eighty patients were included, and 94 postoperative dural reconstructions were performed using FTFG. The postoperative CSF leakage rate was 3.19%. The postoperative CSF leakage rates did not significantly differ between open and endonasal endoscopic surgeries (1.92% vs. 4.88%; p > 0.05). In cases completed using the endonasal endoscopic approach, the postoperative CSF leakage rate was significantly associated with the intraoperative CSF leak flow (p < 0.05).
CONCLUSIONS
Post-ablative dural defect reconstruction using FTFG resulted in low postoperative CSF leakage and complication rates comparable to those of free fascia lata graft from available literature.
Topics: Humans; Female; Male; Middle Aged; Retrospective Studies; Skull Base Neoplasms; Adult; Plastic Surgery Procedures; Temporal Muscle; Aged; Cerebrospinal Fluid Leak; Dura Mater; Fascia; Postoperative Complications; Young Adult; Treatment Outcome; Cerebrospinal Fluid Rhinorrhea; Adolescent
PubMed: 38587969
DOI: 10.1002/hed.27768 -
European Spine Journal : Official... Jun 2024The aim of the present study was to investigate how canal area size changed from before surgery and up to 2 years after decompressive lumbar surgery lumbar spinal... (Randomized Controlled Trial)
Randomized Controlled Trial
Dural Sac Cross-sectional area change from preoperatively and up to 2 years after decompressive surgery for central lumbar spinal stenosis: investigation of operated levels, data from the NORDSTEN study.
PURPOSE
The aim of the present study was to investigate how canal area size changed from before surgery and up to 2 years after decompressive lumbar surgery lumbar spinal stenosis. Further, to investigate if an area change postoperatively (between 3 months to 2 years) was associated with any preoperative demographic, clinical or MRI variables or surgical method used.
METHODS
The present study is analysis of data from the NORDSTEN- SST trial where 437 patients were randomized to one of three mini-invasive surgical methods for lumbar spinal stenosis. The patients underwent MRI examination of the lumbar spine before surgery, and 3 and 24 months after surgery. For all operated segments the dural sac cross-sectional area (DSCA) was measured in mm. Baseline factors collected included age, gender, BMI and smoking habits. Furthermore, surgical method, index level, number of levels operated, all levels operated on and baseline Schizas grade were also included in the analysis.
RESULTS
437 patients were enrolled in the NORDSTEN-SST trial, whereof 310 (71%) had MRI at 3 months and 2 years. Mean DSCA at index level was 52.0 mm (SD 21.2) at baseline, at 3 months it increased to 117.2 mm (SD 43.0) and after 2 years the area was 127.7 mm (SD 52.5). Surgical method, level operated on or Schizas did not influence change in DSCA from 3 to 24 months follow-up.
CONCLUSION
The spinal canal area after lumbar decompressive surgery for lumbar spinal stenosis increased from baseline to 3 months after surgery and remained thereafter unchanged 2 years postoperatively.
Topics: Humans; Spinal Stenosis; Decompression, Surgical; Male; Female; Lumbar Vertebrae; Middle Aged; Aged; Dura Mater; Magnetic Resonance Imaging; Treatment Outcome; Spinal Canal
PubMed: 38587545
DOI: 10.1007/s00586-024-08251-4