Publications by authors named "Raymond Grill"

Nearly all persons with spinal cord injury (SCI) will develop osteoporosis following injury, and further, up to 50% of all persons with SCI will sustain a fracture during their lives. The unique mechanisms driving osteoporosis following SCI remain unknown. The cannabinoid system modulation of bone metabolism through cannabinoid 1/2 (CB1/2) has been of increasing interest for the preservation of bone mass and density in models of osteoporosis.

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Athletes participating in contact sports are at risk for sustaining repeat mild traumatic brain injury (rmTBI). Unfortunately, no pharmacological treatment to lessen the pathophysiology of brain injury has received U.S.

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Closed-head, frontal impacts in which the brain undergoes both lateral and rotational acceleration comprise the majority of human traumatic brain injury (TBI). Here, we utilize a clinically relevant model to examine the effects of a single concussion on aspects of brain integrity: the blood-brain barrier, the perineuronal nets (PNNs), and diffuse axonal injury. Adult, male Sprague-Dawley rats received either a frontal, closed-head concussive TBI, or no injury and were evaluated at 1- or 7-day post-injury.

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Within the spinal cord injured (SCI) population, metabolic dysfunction may be exacerbated. Models of cord injury coupled with metabolic stressors have translational relevance to understand disease progression in this population. In the present study, we used a rat model of thoracic SCI at level T10 (tSCI) and administered diets comprised of either 9% or 40% butterfat to create a unique model system to understand the physiology of weight regulation following cord injury.

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Article Synopsis
  • Traumatic brain injury (TBI) leads to significant brain damage and can cause lasting cognitive issues, with effective treatments still difficult to find.
  • The RhoA-ROCK signaling pathway, activated by TBI, is important as it can negatively impact dendritic spines crucial for memory and information processing.
  • Blocking RhoA-ROCK signaling through methods like gene deletion or using the drug fasudil shows potential to improve motor and cognitive function after TBI, suggesting it may offer a new treatment avenue.
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Individuals that suffer injury to the spinal cord can result in long-term, debilitating sequelae. Spinal cord-injured patients have increased risk for the development of metabolic disease, which can further hinder the effectiveness of treatments to rehabilitate the cord and improve quality of life. In the present study, we sought to understand the impact of high-fat diet (HFD)-induced obesity on spinal cord injury (SCI) by examining transcriptome changes in the area of the injury and rostral and caudal to site of damage 12 wk after injury.

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Background: Prenatal spina bifida (SB) repair with a regenerative patch may improve neurological outcomes by decreasing inflammatory scarring.

Objective: This study aims to compare cryopreserved human umbilical cord (HUC) and biocellulose film (BCF) patches sutured over SB lesions for regeneration of native cells and inflammatory response.

Study Design: Sprague-Dawley rats were gavaged with retinoic acid (RA) on embryonic day 10 to induce SB.

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Spinal cord injury (SCI) remains one of the most debilitating neurological disorders and the majority of SCI patients are in the chronic phase. Previous studies of SCI have usually focused on few genes and pathways at a time. In particular, the biological roles of long non-coding RNAs (lncRNAs) have never been characterized in SCI.

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Spinal cord injury (SCI) results in devastating changes to almost all aspects of a patient's life. In addition to a permanent loss of sensory and motor function, males also will frequently exhibit a profound loss of fertility through poorly understood mechanisms. We demonstrate that SCI causes measureable pathology in the testis both acutely (24 h) and chronically up to 1.

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Objectives: The objective of our study was to test the hypothesis that in utero repair of surgically created spina bifida in a sheep model using cryopreserved human umbilical cord (HUC) patch improves neurological outcome.

Methods: Spina bifida with myelotomy was surgically created in timed pregnant ewes at gestational day (GD) 75. The fetuses were randomly assigned to unrepaired versus HUC and treated at GD 95 and then delivered at GD 140.

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Article Synopsis
  • Neural stem cells (NSCs) may help recover from brain trauma not just by replacing neurons, but also by influencing the immune response in the brain after an injury.
  • In a study with mice, injecting human NSCs reduced harmful inflammatory responses and shifted the behavior of immune cells (microglia/macrophages) toward a less harmful state (M2 phenotype).
  • Although the overall size of brain lesions didn't significantly decrease, the presence of NSCs helped lower the buildup of specific injury markers, suggesting that their positive effects are more about modulating inflammation than direct neuronal replacement.
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Traumatic brain injury (TBI) differs in severity from severe to mild. This study examined whether a combination of the drugs minocycline (MINO) plus N-acetylcysteine (NAC) produces behavioral and histological improvements in a mild version of the controlled cortical impact model of TBI (mCCI). Following mCCI, rats acquired an active place avoidance task by learning the location of a stationary shock zone on a rotating arena.

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We have recently demonstrated that injured patients in hemorrhagic shock shed syndecan 1 and that the early use of fresh frozen plasma (FFP) in these patients is correlated with improved clinical outcomes. As the lungs are frequently injured after trauma, we hypothesized that hemorrhagic shock-induced shedding of syndecan 1 exposes the underlying pulmonary vascular endothelium to injury resulting in inflammation and hyperpermeability and that these effects would be mitigated by FFP. In vitro, pulmonary endothelial permeability, endothelial monolayer flux, transendothelial electrical resistance, and leukocyte-endothelial binding were measured in pulmonary endothelial cells after incubation with equal volumes of FFP or lactated Ringer's (LR).

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Inflammation is a major factor shaping outcome during the early, acute phase of traumatic spinal cord injury (SCI). It is known that pro-inflammatory signaling within the injured spinal cord drives pathological alterations in neurosensory processing and shapes functional outcome early after injury. However, it is unclear whether inflammation persists into the chronic phase of injury or shapes sensory processing long after injury.

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There are currently no proven effective treatments that can improve recovery of function in spinal cord injury (SCI) patients. Many therapeutic compounds have shown promise in pre-clinical studies, but clinical trials have been largely unsuccessful. P-glycoprotein (Pgp, Abcb1b) is a drug efflux transporter of the blood-spinal cord barrier that limits spinal cord penetration of blood-borne xenobiotics.

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Concussive injury (or mild traumatic brain injury; mTBI) can exhibit features of focal or diffuse injury patterns. We compared and contrasted the cellular and molecular responses after mild controlled cortical impact (mCCI; a focal injury) or fluid percussion injury (FPI; a diffuse injury) in rats. The rationale for this comparative analysis was to investigate the brain's response to mild diffuse versus mild focal injury to identify common molecular changes triggered by these injury modalities and to determine the functional pathways altered after injury that may provide novel targets for therapeutic intervention.

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Mild traumatic brain injury (mTBI) results in an estimated 75-90% of the 1.7 million TBI-related emergency room visits each year. Post-concussion symptoms, which can include impaired memory problems, may persist for prolonged periods of time in a fraction of these cases.

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Syndecan 1 is the predominant heparan sulfate proteoglycan found on the surface of epithelial cells and, like glutamine, is essential in maintaining the intestinal epithelial barrier. We therefore hypothesized that loss of epithelial syndecan 1 would abrogate the gut-protective effects of enteral glutamine. Both an in vitro and in vivo model of gut ischemia-reperfusion (IR) was utilized.

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Blast injury is the most prevalent source of mortality and morbidity among combatants in Operations Iraqi and Enduring Freedom. Blast-induced neurotrauma (BINT) is a common cause of mortality, and even mild BINT may be associated with chronic cognitive and emotional deficits. In addition to military personnel, the increasing use of explosives by terrorists has resulted in growing numbers of blast injuries in civilian populations.

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The rat spinal-cord-injury (SCI) model is widely used to study the pathologic mechanisms that contribute to sensory and motor dysfunction in humans. This model is thought to mimic many of the negative outcomes experienced by humans after spinal contusion injury. We theorized that manual bladder expression contributed to the kidney and bladder lesions reported in previous studies using the rat SCI model.

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Spinal cord injury (SCI) is often accompanied by osteoporosis in the sublesional regions of the pelvis and lower extremities, leading to a higher frequency of fractures. As these fractures often occur in regions that have lost normal sensory function, the patient is at a greater risk of fracture-dependent pathologies, including death. SCI-dependent loss in both bone mineral density (BMD, grams/cm2) and bone mineral content (BMC, grams) has been attributed to mechanical disuse, aberrant neuronal signaling and hormonal changes.

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The purpose of this study was to investigate the increased susceptibility of the brain, after a controlled mild cortical impact injury, to a secondary ischemic insult. The effects of the duration and the timing of the secondary insult after the initial cortical injury were studied. Rats anesthetized with isoflurane underwent a 3 m/sec, 2.

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Although most investigations of the mechanisms underlying chronic pain after spinal cord injury (SCI) have examined the central nervous system (CNS), recent studies have shown that nociceptive primary afferent neurons display persistent hyperexcitability and spontaneous activity in their peripheral branches and somata in dorsal root ganglia (DRG) after SCI. This suggests that SCI-induced alterations of primary nociceptors contribute to central sensitization and chronic pain after SCI. Does SCI also promote growth of these neurons' fibers, as has been suggested in some reports? The present study tests the hypothesis that SCI induces an intrinsic growth-promoting state in DRG neurons.

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Background: Traumatic brain injury (TBI) sets in motion cascades of biochemical changes that result in delayed cell death and altered neuronal architecture. Studies have demonstrated that inhibition of glycogen synthase kinase-3 (GSK-3) effectively reduces apoptosis following a number of stimuli. The Wnt family of proteins, and growth factors are two major factors that regulate GSK-3 activity.

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A major hurdle for regeneration after spinal cord injury (SCI) is the ability of axons to penetrate and grow through the scar tissue. After SCI, inflammatory cells, astrocytes and meningeal cells all play a role in developing the glial scar. In addition, degradation of native high molecular weight (MW) hyaluronic acid (HA), a component of the extracellular matrix, has been shown to induce activation and proliferation of astrocytes.

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