Ablation of oligodendrogenesis in adult mice alters brain microstructure and activity independently of behavioral deficits.

Oligodendrocytes continue to differentiate from their precursor cells even in adulthood, a process that can be modulated by neuronal activity and experience. Previous work has indicated that conditional ablation of oligodendrogenesis in adult mice leads to learning and memory deficits in a range of behavioral tasks. The current study replicated and re-evaluated evidence for a role of oligodendrogenesis in motor learning, using a complex running wheel task.

Feasibility of an MR-based digital specimen for tongue cancer resection specimens: a novel approach for margin evaluation.

Objective: This study explores the feasibility of ex-vivo high-field magnetic resonance (MR) imaging to create digital a three-dimensional (3D) representations of tongue cancer specimens, referred to as the "MR-based digital specimen" (MR-DS). The aim was to create a method to assist surgeons in identifying and localizing inadequate resection margins during surgery, a critical factor in achieving locoregional control.

Methods: Fresh resection specimens of nine tongue cancer patients were imaged in a 7 Tesla small-bore MR, using a high-resolution multislice and 3D T2-weighted Turbo Spin Echo.

Propofol anesthesia improves stroke outcomes over isoflurane anesthesia-a longitudinal multiparametric MRI study in a rodent model of transient middle cerebral artery occlusion.

General anesthesia is routinely used in endovascular thrombectomy procedures, for which volatile gas and/or intravenous propofol are recommended. Emerging evidence suggests propofol may have superior effects on disability and/or mortality rates, but a mode-of-action underlying these class-specific effects remains unknown. Here, a moderate isoflurane or propofol dosage on experimental stroke outcomes was retrospectively compared using serial multiparametric MRI and behavioral testing.

Hyperperfusion profiles after recanalization differentially associate with outcomes in a rat ischemic stroke model.

Futile recanalization hampers prognoses of ischemic stroke after successful mechanical thrombectomy, hypothetically through post-recanalization perfusion deficits, onset-to-groin delays and sex effects. Clinically, acute multiparametric imaging studies remain challenging. We assessed possible relationships between these factors and disease outcome after experimental cerebral ischemia-reperfusion, using translational MRI, behavioral testing and multi-model inference analyses.

Post-mortem Magnetic Resonance Imaging of Degenerating and Reorganizing White Matter in Post-stroke Rodent Brain.

Magnetic resonance imaging (MRI) allows noninvasive and non-destructive imaging of brain tissue. More specifically, the status of white matter fibers can be measured with diffusion-weighted MRI, enabling assessment of structural degeneration or remodeling of white matter tracts in diseased brain. Here, we describe the preparation of post-stroke rodent brain samples for post-mortem high-resolution 3D diffusion-weighted MR imaging, accompanied with guidelines for acquiring and processing the images.

Thermosensitive Biodegradable Hydrogels for Local and Controlled Cerebral Delivery of Proteins: MRI-Based Monitoring of and Protein Release.

Hydrogels have been suggested as novel drug delivery systems for sustained release of therapeutic proteins in various neurological disorders. The main advantage these systems offer is the controlled, prolonged exposure to a therapeutically effective dose of the released drug after a single intracerebral injection. Characterization of controlled release of therapeutics from a hydrogel is generally performed , as current methods do not allow for measurements of spatiotemporal distribution and release kinetics of a loaded protein.

imaging of cerebral glucose metabolism informs on subacute to chronic post-stroke tissue status - A pilot study combining PET and deuterium metabolic imaging.

Recanalization therapy after acute ischemic stroke enables restoration of cerebral perfusion. However, a significant subset of patients has poor outcome, which may be caused by disruption of cerebral energy metabolism. To assess changes in glucose metabolism subacutely and chronically after recanalization, we applied two complementary imaging techniques, fluorodeoxyglucose (FDG) positron emission tomography (PET) and deuterium (H) metabolic imaging (DMI), after 60-minute transient middle cerebral artery occlusion (tMCAO) in C57BL/6 mice.

Memantine treatment does not affect compulsive behavior or frontostriatal connectivity in an adolescent rat model for quinpirole-induced compulsive checking behavior.

Rationale: Compulsivity often develops during childhood and is associated with elevated glutamate levels within the frontostriatal system. This suggests that anti-glutamatergic drugs, like memantine, may be an effective treatment.

Objective: Our goal was to characterize the acute and chronic effect of memantine treatment on compulsive behavior and frontostriatal network structure and function in an adolescent rat model of compulsivity.

Prolonged release of VEGF and Ang1 from intralesionally implanted hydrogel promotes perilesional vascularization and functional recovery after experimental ischemic stroke.

Injectable hydrogels can generate and support pro-repair environments in injured tissue. Here we used a slow-releasing drug carrying -forming hydrogel to promote post-stroke recovery in a rat model. Release kinetics were measured and with MRI, using gadolinium-labeled albumin (Galbumin), which demonstrated prolonged release over multiple weeks.

Molecular Magnetic Resonance Imaging of Vascular Inflammation After Recanalization in a Rat Ischemic Stroke Model.

Background And Purpose: Brain imaging has become central in the management of acute ischemic stroke. Detection of parenchymal injury and perfusion enables characterization of the extent of ischemic damage, which guides treatment decision-making. Additional assessment of secondary events, such as inflammation, which may particularly arise after recanalization, may improve diagnosis and (supplementary) treatment selection.

Remote Corticospinal Tract Degeneration After Cortical Stroke in Rats May Not Preclude Spontaneous Sensorimotor Recovery.

Recovery of motor function after stroke appears to be related to the integrity of axonal connections in the corticospinal tract (CST) and corpus callosum, which may both be affected after cortical stroke. In the present study, we aimed to elucidate the relationship of changes in measures of the CST and transcallosal tract integrity, with the interhemispheric functional connectivity and sensorimotor performance after experimental cortical stroke. We conducted in vivo diffusion magnetic resonance imaging (MRI), resting-state functional MRI, and behavior testing in twenty-five male Sprague Dawley rats recovering from unilateral photothrombotic stroke in the sensorimotor cortex.

Activation response and functional connectivity change in rat cortex after bilateral transcranial direct current stimulation-An exploratory study.

Transcranial direct current stimulation (tDCS) is a noninvasive brain stimulation technique implicated as a promising adjunct therapy to improve motor function through the neuromodulation of brain networks. Particularly bilateral tDCS, which affects both hemispheres, may yield stronger effects on motor learning than unilateral stimulation. Therefore, the aim of this exploratory study was to develop an experimental model for simultaneous magnetic resonance imaging (MRI) and bilateral tDCS in rats, to measure instant and resultant effects of tDCS on network activity and connectivity.

Imaging Markers for the Characterization of Gray and White Matter Changes from Acute to Chronic Stages after Experimental Traumatic Brain Injury.

Despite clinical symptoms, a large majority of people with mild traumatic brain injury (TBI) have normal computed tomography (CT) and magnetic resonance imaging (MRI) scans. Therefore, present-day neuroimaging tools are insufficient to diagnose or classify low grades of TBI. Advanced neuroimaging techniques, such as diffusion-weighted and functional MRI, may yield novel biomarkers that may aid in the diagnosis of TBI.

Active Recharge Burst and Tonic Spinal Cord Stimulation Engage Different Supraspinal Mechanisms: A Functional Magnetic Resonance Imaging Study in Peripherally Injured Chronic Neuropathic Rats.

Objectives: To assess the supraspinal working mechanisms of the burst spinal cord stimulation (SCS) mode, we used functional magnetic resonance imaging (fMRI) in chronic neuropathic rats. We hypothesized that active recharge burst SCS would induce a more profound blood oxygenation level-dependent (BOLD) signal increase in areas associated with cognitive-emotional aspects of pain, as compared to tonic SCS.

Methods: Sprague Dawley rats (n = 17) underwent a unilateral partial sciatic nerve ligation, which resulted in chronic neuropathic pain.

Distinct structure-function relationships across cortical regions and connectivity scales in the rat brain.

An improved understanding of the structure-function relationship in the brain is necessary to know to what degree structural connectivity underpins abnormal functional connectivity seen in disorders. We integrated high-field resting-state fMRI-based functional connectivity with high-resolution macro-scale diffusion-based and meso-scale neuronal tracer-based structural connectivity, to obtain an accurate depiction of the structure-function relationship in the rat brain. Our main goal was to identify to what extent structural and functional connectivity strengths are correlated, macro- and meso-scopically, across the cortex.

Diet as connecting factor: Functional brain connectivity in relation to food intake and sucrose tasting, assessed with resting-state functional MRI in rats.

Eating disorders and obesity form a major health problem in Western Society. To be able to provide adequate treatment and prevention, it is necessary to understand the neural mechanisms underlying the development of eating disorders and obesity. Specific brain networks have been shown to be involved in feeding behavior.

Branching Pattern of the Cerebral Arterial Tree.

Quantitative data on branching patterns of the human cerebral arterial tree are lacking in the 1.0-0.1 mm radius range.

High resolution 7T and 9.4T-MRI of human cerebral arterial casts enables accurate estimations of the cerebrovascular morphometry.

Quantitative data on the morphology of the cerebral arterial tree could aid in modelling and understanding cerebrovascular diseases, but is scarce in the range between 200 micrometres and 1 mm diameter arteries. Traditional manual measurements are difficult and time consuming. 7T-MRI and 9.

Differences in structural and functional networks between young adult and aged rat brains before and after stroke lesion simulations.

Neural network changes during aging may contribute to vulnerability and resilience to brain lesions in age-related neurological disorders, such as stroke. However, the relationship between age-related neural network features and stroke outcome is unknown. Therefore, we assessed structural and functional network status in young adult and aged rat brain, and measured the effects of simulated stroke lesions.