Culture substrate stiffness impacts human myoblast contractility-dependent proliferation and nuclear envelope wrinkling.

Understanding how biophysical and biochemical microenvironmental cues together influence the regenerative activities of muscle stem cells and their progeny is crucial in strategizing remedies for pathological dysregulation of these cues in aging and disease. In this study, we investigated the cell-level influences of extracellular matrix (ECM) ligands and culture substrate stiffness on primary human myoblast contractility and proliferation within 16 h of plating and found that tethered fibronectin led to stronger stiffness-dependent responses compared to laminin and collagen. A proteome-wide analysis further uncovered cell metabolism, cytoskeletal and nuclear component regulation distinctions between cells cultured on soft and stiff substrates.

Lipidomic-Based Approach to 10 s Classification of Major Pediatric Brain Cancer Types with Picosecond Infrared Laser Mass Spectrometry.

Picosecond infrared laser mass spectrometry (PIRL-MS) is shown, through a retrospective patient tissue study, to differentiate medulloblastoma cancers from pilocytic astrocytoma and two molecular subtypes of ependymoma (PF-EPN-A, ST-EPN-RELA) using laser-extracted lipids profiled with PIRL-MS in 10 s of sampling and analysis time. The average sensitivity and specificity values for this classification, taking genomic profiling data as standard, were 96.41 and 99.

Development of the cervical myelopathy severity index: a new patient reported outcome measure to quantify impairments and functional limitations.

Background Context: Existing degenerative cervical myelopathy (DCM) severity scales have significant shortcomings, creating a strong impetus for the development of a practical measurement tool with sound psychometric properties.

Purpose: This work reports the item generation and reduction of the Cervical Myelopathy Severity Index (CMSI), a new DCM patient-reported outcome measure of symptoms and functional limitations.

Design: Prospective observational study.

Metabolic Lipids in Melanoma Enable Rapid Determination of Actionable BRAF-V600E Mutation with Picosecond Infrared Laser Mass Spectrometry in 10 s.

Rapid molecular profiling of biological tissues with picosecond infrared laser mass spectrometry (PIRL-MS) has enabled the detection of clinically important histologic types and molecular subtypes of human cancers in as little as 10 s of data collection and analysis time. Utilizing an engineered cell line model of actionable BRAF-V600E mutation, we observed statistically significant differences in 10 s PIRL-MS molecular profiles between BRAF-V600E and BRAF-wt cells. Multivariate statistical analyses revealed a list of mass-to-charge (/) values most significantly responsible for the identification of BRAF-V600E mutation status in this engineered cell line that provided a highly controlled testbed for this observation.

Evaluation of Posterior Ligamentous Complex Injury in Thoracolumbar Burst Fractures: Correlation Analysis of CT and MRI Findings.

The goal of this study is to perform correlation analysis of Computed tomography (CT) and magnetic resonance imaging (MRI) results in posterior ligament complex (PLC) injury and define the morphological traits of thoracolumbar (TL) burst fractures connected to PLC injury. Forty patients with surgically repaired TL burst fractures between January 2013 and December 2020 were retrospectively analyzed. The patients were split into two groups for comparison based on MRI (Group P: patients with a confirmed or suspected PLC injury; Group N: patients with PLC injury denied).

Picosecond Infrared Laser Mass Spectrometry Identifies a Metabolite Array for 10 s Diagnosis of Select Skin Cancer Types: A Proof-of-Concept Feasibility Study.

Currently, a large number of skin biopsies are taken for each true skin cancer case detected, creating a need for a rapid, high sensitivity, and specificity skin cancer detection tool to reduce the number of unnecessary biopsies taken from benign tissue. Picosecond infrared laser mass spectrometry (PIRL-MS) using a hand-held sampling probe is reported to detect and classify melanoma, squamous cell carcinoma, and normal skin with average sensitivity and specificity values of 86-95% and 91-98%, respectively (at a 95% confidence level) solely requiring 10 s or less of total data collection and analysis time. Classifications are not adversely affected by specimen's quantity of melanin pigments and are mediated by a number of metabolic lipids, further identified herein as potential biomarkers for skin cancer-type differentiation, 19 of which were sufficient here (as a fully characterized metabolite array) to provide high specificity and sensitivity classification of skin cancer types.

Clinical and Radiological Clues of Traumatic Craniocervical Junction Injuries Requiring Occipitocervical Fusion to Early Diagnosis.

Objective: The purpose of this study is to find the clinical and radiographic characteristics of traumatic craniocervical junction (CCJ) injuries requiring occipitocervical fusion (OC fusion) for early diagnosis and surgical intervention.

Methods: We retrospectively reviewed 12 patients with CCJ injuries presenting to St. Michaels Hospital in Toronto who underwent OC fusion and looked into the following variables; (1) initial trauma data on emergency room arrival, (2) associated injuries, (3) imaging characteristics of computed tomography (CT) scan and magnetic resonance imaging (MRI), (4) surgical procedures, surgical complications, and neurological outcome.

Spinal arachnoid web-a distinct entity of focal arachnopathy with favorable long-term outcome after surgical resection: analysis of a multicenter patient population.

Background Context: Spinal arachnoid web (SAW) is a rare condition characterized by focal thickening of the arachnoid membrane causing displacement and compression of the spinal cord with progressive symptoms and neurological deficits. Recent reports and clinical experience suggest that SAW is a distinct entity with specific radiological findings and treatment strategies distinguishable from other arachnopathies and potential differential diagnoses.

Purpose: To better define the diagnostic and clinical features, treatment options and outcomes of surgically treated SAW.

tissue pathology from spatially encoded mass spectrometry classifiers visualized in real time through augmented reality.

Integration between a hand-held mass spectrometry desorption probe based on picosecond infrared laser technology (PIRL-MS) and an optical surgical tracking system demonstrates tissue pathology from point-sampled mass spectrometry data. Spatially encoded pathology classifications are displayed at the site of laser sampling as color-coded pixels in an augmented reality video feed of the surgical field of view. This is enabled by two-way communication between surgical navigation and mass spectrometry data analysis platforms through a custom-built interface.

Mass Spectrometry Imaging Reveals a Gradient of Cancer-like Metabolic States in the Vicinity of Cancer Not Seen in Morphometric Margins from Microscopy.

Spatially resolved ambient mass spectrometry imaging methods have gained popularity to characterize cancer sites and their borders using molecular changes in the lipidome. This utility, however, is predicated on metabolic homogeneity at the border, which would create a sharp molecular transition at the morphometric borders. We subjected murine models of human medulloblastoma brain cancer to mass spectrometry imaging, a technique that provides a direct readout of tissue molecular content in a spatially resolved manner.

Complete resection and untethering of the cervical and thoracic spinal dermal sinus tracts in adult patients.

Dermal sinus tracts (DSTs) of the cervical and thoracic spine are extremely rare, particularly in adult patients because diagnosis is typically made in the early stage after birth by pediatricians. These cases should be treated surgically as soon as possible to prevent neurological sequelae. This report describes two rare adult cases with cervical and thoracic spine DSTs.

Possible Double Crush Syndrome Caused by Iatrogenic Acquired Lumbosacral Epidermoid Tumor and Concomitant Sacral Tarlov Cyst.

We describe a rare case of 42-year-old female who had possible double crush syndrome caused by iatrogenic spinal epidermoid tumor (ET) associated with lumbar puncture as well as concomitant sacral Tarlov cyst in close proximity. She presented with progressive left-sided perianal pain. She had a history of a Caesarean section with lumbar spinal anesthesia.

A 96-well culture platform enables longitudinal analyses of engineered human skeletal muscle microtissue strength.

Three-dimensional (3D) in vitro models of human skeletal muscle mimic aspects of native tissue structure and function, thereby providing a promising system for disease modeling, drug discovery or pre-clinical validation, and toxicity testing. Widespread adoption of this research approach is hindered by the lack of easy-to-use platforms that are simple to fabricate and that yield arrays of human skeletal muscle micro-tissues (hMMTs) in culture with reproducible physiological responses that can be assayed non-invasively. Here, we describe a design and methods to generate a reusable mold to fabricate a 96-well platform, referred to as MyoTACTIC, that enables bulk production of 3D hMMTs.

Epidemiology and Impact of Spinal Cord Injury in the Elderly: Results of a Fifteen-Year Population-Based Cohort Study.

Although experience suggests a shift in the epidemiology of spinal cord injury (SCI) toward an older demographic, population studies are lacking. We aimed to evaluate (1) how the epidemiology and age profile of SCI have changed over time, and (2) how increased age impacts health outcomes up to 15 years post-injury. A population-based cohort study was performed in Ontario including adults diagnosed with traumatic SCI between 2002 and 2017.

Dual Laser and Desorption Electrospray Ionization Mass Spectrometry Imaging Using the Same Interface.

For a more comprehensive characterization of molecular heterogeneities of matter, multimodal mass spectrometry imaging must be developed to take advantage of the complementarity of information available through different ionization mechanisms. We report the design, implementation, and performance validation of a laser desorption imaging interface composed of add-on components that adapt a commercial Desorption Electrospray Ionization Mass Spectrometry (DESI-MS) imaging interface for dual imaging of Picosecond Infrared Laser Mass Spectrometry (PIRL-MS) with DESI-MS. The interface utilizes hardware elements and data analysis pipelines already established for DESI-MS imaging, and was further validated in cancer margin assessments using human medulloblastoma cancers.

Quantification of computational geometric congruence in surface-based registration for spinal intra-operative three-dimensional navigation.

Background Context: Computer-assisted navigation (CAN) may guide spinal instrumentation, and requires alignment of patient anatomy to imaging. Iterative closest-point (ICP) algorithms register anatomical and imaging surface datasets, which may fail in the presence of geometric symmetry (congruence), leading to failed registration or inaccurate navigation. Here we computationally quantify geometric congruence in posterior spinal exposures, and identify predictors of potential navigation inaccuracy.

Diffuse idiopathic skeletal hyperostosis masquerading as asthma: case report.

A 52-year-old man with a 10-year history of treatment-resistant asthma presented with repeated exacerbations over the course of 10 months. His symptoms were not responsive to salbutamol or inhaled corticosteroid agents, and he developed avascular necrosis of his left hip as a result of prolonged steroid therapy. Physical examination and radiography revealed signs consistent with diffuse idiopathic skeletal hyperostosis (DISH), including a C7-T1 osteophyte causing severe tracheal compression.

Picosecond Infrared Laser Desorption Mass Spectrometry Identifies Medulloblastoma Subgroups on Intrasurgical Timescales.

Medulloblastoma (MB) is a pediatric malignant brain tumor composed of four different subgroups (WNT, SHH, Group 3, Group 4), each of which are a unique biological entity with distinct clinico-pathological, molecular, and prognostic characteristics. Although risk stratification of patients with MB based on molecular features may offer personalized therapies, conventional subgroup identification methods take too long and are unable to deliver subgroup information intraoperatively. This limitation prevents subgroup-specific adjustment of the extent or the aggressiveness of the tumor resection by the neurosurgeon.

Surgical treatment of a thoracic ventral intradural arachnoid cyst associated with syringomyelia: case report.

The pathogenesis of thoracic ventral intradural spinal arachnoid cyst (ISAC) is unknown due to its extremely low incidence. In addition, its surgical treatment is complicated because of the ventral location, large craniocaudal extension, and frequent coexistence of syringomyelia. The optimal surgical strategy for thoracic ventral ISAC remains unclear and continues to be a matter of debate.

Intraoperative Ultrasound-Guided Posterior Cervical Laminectomy for Degenerative Cervical Myelopathy.

Objective: We present our experience with routine intraoperative ultrasound (IOUS)-guided posterior cervical laminectomy (PCL) in patients with degenerative cervical myelopathy (DCM), describe the technique used, and describe relevant IOUS findings that may impact the surgical procedure.

Methods: Three illustrative cases are presented of patients (age range, 67-79 years) who underwent PCL with IOUS guidance and instrumented fusion for DCM. Intraoperative standard B-mode images were obtained with a linear array 6.

Reduction in surgical site infection with suprafascial intrawound application of vancomycin powder in instrumented posterior spinal fusion: a retrospective case-control study.

OBJECTIVE Recent studies have demonstrated the efficacy of subfascial intrawound application of vancomycin powder in spine surgery in reducing the rate of surgical site infections (SSIs). However, to date no study has evaluated the efficacy and safety of suprafascial application of vancomycin powder in spine surgery. The purpose of this study was to quantify the rate of SSIs after open instrumented posterior spinal fusion with and without application of suprafascial vancomycin powder and to evaluate the rate of vancomycin powder-related local adverse effects.

Clinical and Radiological Outcomes of Microscopic Lumbar Foraminal Decompression: A Pilot Analysis of Possible Risk Factors for Restenosis.

A single-center retrospective comparative study was designed to identify the risk factors for restenosis of lumbar foraminal stenosis (LFS) after microscopic foraminal decompression (MFD). 21 consecutive patients who underwent single-level MFD with an average of 19-month follow-up were divided into two study groups based on clinical outcomes; group 1 (7 patients with poor outcomes requiring revision surgery), group 2 (14 patients with good outcomes with no revision surgery required). Changes of lumbar spinal alignment on plain standing radiographs were compared and analyzed between two study groups to investigate the pathology and risk factors associated with restenosis after MFD.

Chiari Type 1 Malformation-induced Intracranial Hypertension with Diffuse Brain Edema Treated with Foramen Magnum Decompression: A Case Report.

Chiari type 1 malformation (CM1) rarely causes papilloedema, which is indicative of high intracranial pressure with or without ventricular dilatation. Furthermore, concomitant brain parenchymal abnormalities have not been reported to date. In this paper, the authors report on a young woman of CM1-induced intracranial hypertension (ICH) with diffuse brain edema with a focus on venous sinus assessment, and discuss the surgical strategy.

Surgical Treatment of Rotational Vertebral Artery Syndrome Induced by Spinal Tumor: A Case Report and Literature Review.

Vertebrobasilar insufficiency (VBI) provoked by physiological head rotation is known as rotational vertebral artery syndrome (RVAS) or Bow Hunter syndrome. RVAS most often occurs at C1-2 level with head rotation and presents with symptoms of VBI. Several previously published studies have reported RVAS at subaxial sites (V2 segment), however, tumor-induced RVAS has never been reported.