Amyloid β accumulation in axons after traumatic brain injury in humans

2003 ◽  
Vol 98 (5) ◽  
pp. 1072-1077 ◽  
Author(s):  
Douglas H. Smith ◽  
Xiao-han Chen ◽  
Akira Iwata ◽  
David I. Graham

Object. Although plaques composed of amyloid β (Aβ) have been found shortly after traumatic brain injury (TBI) in humans, the source for this Aβ has not been identified. In the present study, the authors explored the potential relationship between Aβ accumulation in damaged axons and associated Aβ plaque formation. Methods. The authors performed an immunohistochemical analysis of paraffin-embedded sections of brain from 12 patients who died after TBI and from two control patients by using antibodies selective for Aβ peptides, amyloid precursor protein (APP), and neurofilament (NF) proteins. In nine brain-injured patients, extensive colocalizations of Aβ, APP, and NF protein were found in swollen axons. Many of these immunoreactive axonal profiles were present close to Aβ plaques or were surrounded by Aβ staining, which spread out into the tissue. Immunoreactive profiles were not found in the brains of the control patients. Conclusions. The results of this study indicate that damaged axons can serve as a large reservoir of Aβ, which may contribute to Aβ plaque formation after TBI in humans.

1988 ◽  
Vol 68 (1) ◽  
pp. 62-66 ◽  
Author(s):  
Jane A. Norton ◽  
Linda G. Ott ◽  
Craig McClain ◽  
Linas Adams ◽  
Robert J. Dempsey ◽  
...  

✓ Calorie and protein supplementation improves nutritional status. This support may improve outcome and decrease morbidity and mortality in acutely brain-injured patients. Investigators have observed a poor tolerance to enteral feedings after brain injury and have noted that this persists for approximately 14 days postinjury. This delay has been attributed to increased gastric residuals, prolonged paralytic ileus, abdominal distention, aspiration pneumonitis, and diarrhea. In the present investigation, 23 brain-injured patients with an admission 24-hour peak Glasgow Coma Scale (GCS) score between 4 and 10 were studied for 18 days from hospital admission. The mean duration from injury to initiation of full-strength, full-rate enteral feeding was 11.5 days. Seven of the 23 patients tolerated enteral feedings within the first 7 days following hospital admission (mean 4.3 days), four patients tolerated feedings between 7 and 10 days postadmission (mean 9 days), and 12 patients did not tolerate feedings until after 10 days postinjury (mean 15.9 days). There was a marginally significant relationship between low GCS scores on admission and length of days to enteral feeding tolerance (p = 0.07). A significant inverse relationship was observed between daily peak intracranial pressure (ICP) and time to tolerance of feedings (p = 0.02). There was no significant relationship between feeding tolerance and days to return of bowel sounds (p = 0.12). Serum albumin levels decreased during the investigation (mean ± standard error to the mean: 3.2 ± 0.12 gm/dl on Day 1; 2.7 ± 0.23 gm/dl on Day 16; normal = 3.5 to 5.0 gm/dl), whereas the percentage of patients tolerating feedings increased over the course of the study. The authors conclude that patients with acute severe brain injury do not adequately tolerate feedings via the enteral route in the early postinjury period. Tolerance of enteral feeding is inversely related to increased ICP and severity of brain injury. It is suggested that parenteral nutritional support is required following brain injury until enteral nutrition can be tolerated.


2001 ◽  
Vol 95 (4) ◽  
pp. 674-679 ◽  
Author(s):  
Bum-Tae Kim ◽  
Vemuganti L. Raghavendra Rao ◽  
Kurt A. Sailor ◽  
Kellie K. Bowen ◽  
Robert J. Dempsey

Object. The purpose of this study was to evaluate whether glial cell line—derived neurotrophic factor (GDNF) can protect against hippocampal neuronal death after traumatic brain injury (TBI). Methods. Male Sprague—Dawley rats were subjected to moderate TBI with a controlled cortical impact device while in a state of halothane-induced anesthesia. Then, GDNF or artificial cerebrospinal fluid ([aCSF]; vehicle) was infused into the frontal horn of the left lateral ventricle. In eight brain-injured and eight sham-operated rats, GDNF was infused continuously for 7 days (200 ng/day intracerebroventricularly at a rate of 8.35 ng/0.5 µl/hour). An equal volume of vehicle was infused at the same rate into the remaining eight brain-injured and eight sham-operated rats. Seven days post-injury, all rats were killed. Their brains were sectioned and stained with cresyl violet, and the hippocampal neuronal loss was evaluated in the CA2 and CA3 regions with the aid of microscopy. A parallel set of sections from each brain was subjected to immunoreaction with antibodies against glial fibrillary acidic protein (GFAP; astroglia marker). In the aCSF-treated group, TBI resulted in a significant neuronal loss in the CA2 (60%, p < 0.05) and CA3 regions (68%, p < 0.05) compared with the sham-operated control animals. Compared with control rats infused with aCSF, GDNF infusion significantly decreased the TBI-induced neuronal loss in both the CA2 (58%, p < 0.05) and CA3 regions (51%, p < 0.05). There was no difference in the number of GFAP-positive astroglial cells in the GDNF-infused rats in the TBI and sham-operated groups compared with the respective vehicle-treated groups. Conclusions. The authors found that GDNF treatment following TBI is neuroprotective.


1973 ◽  
Vol 39 (3) ◽  
pp. 405-407 ◽  
Author(s):  
William F. Bouzarth ◽  
J. N. Crowley ◽  
Harris R. Clearfield

✓ A patient with severe brain injury began vomiting 12 weeks after admission. This magnified a progressive weight loss of 34 kg. Vascular compression of the duodenum was confirmed as the cause of the vomiting. With hyperalimentation, vomiting stopped and weight gain occurred. This easily reversible syndrome should be considered in the differential diagnosis of vomiting in brain-injured patients with weight loss.


2000 ◽  
Vol 92 (6) ◽  
pp. 1040-1044 ◽  
Author(s):  
Gregory W. Hornig

✓ This report documents clinical features in five children who developed transient reddening of the skin (epidermal flushing) in association with acute elevations in intracranial pressure (ICP). Four boys and one girl (ages 9–15 years) deteriorated acutely secondary to intracranial hypertension ranging from 30 to 80 mm Hg in the four documented cases. Two patients suffered from ventriculoperitoneal shunt malfunctions, one had diffuse cerebral edema secondary to traumatic brain injury, one was found to have pneumococcal meningitis and hydrocephalus, and one suffered an intraventricular hemorrhage and hydrocephalus intraoperatively. All patients were noted to have developed epidermal flushing involving either the upper chest, face, or arms during their period of neurological deterioration. The response was transient, typically lasting 5 to 15 minutes, and dissipated quickly. The flushing reaction is postulated to be a centrally mediated response to sudden elevations in ICP. Several potential mechanisms are discussed. Flushing has clinical importance because it may indicate significant elevations in ICP when it is associated with neurological deterioration. Because of its transient nature, the importance of epidermal flushing is often unrecognized; its presence confirms the need for urgent treatment.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jason H. Boulter ◽  
Margaret M. Shields ◽  
Melissa R. Meister ◽  
Gregory Murtha ◽  
Brian P. Curry ◽  
...  

Traumatic brain injury is a rapidly increasing source of morbidity and mortality across the world. As such, the evaluation and management of traumatic brain injuries ranging from mild to severe are under active investigation. Over the last two decades, quantitative pupillometry has been increasingly found to be useful in both the immediate evaluation and ongoing management of traumatic brain injured patients. Given these findings and the portability and ease of use of modern pupillometers, further adoption and deployment of quantitative pupillometers into the preclinical and hospital settings of both resource rich and medically austere environments.


2018 ◽  
pp. 155-164
Author(s):  
Maranatha Ayodele ◽  
Kristine O’Phelan

Advancements in the critical care of patients with various forms of acute brain injury (traumatic brain injury, subarachnoid hemorrhage, stroke, etc.) in its current evolution recognizes that in addition to the initial insult, there is a secondary cascade of physiological events in the injured brain that contribute significantly to morbidity and mortality. Multimodality monitoring (MMM) in neurocritical care aims to recognize this secondary cascade in a timely manner. With early recognition, critical care of brain-injured patients may then be tailored to preventing and alleviating this secondary injury. MMM includes a variety of invasive and noninvasive techniques aimed at monitoring brain physiologic parameters such as intracranial pressure, perfusion, oxygenation, blood flow, metabolism, and electrical activity. This chapter provides an overview of these techniques and offers a practical guide to their integration and use in the intensive care setting.


2001 ◽  
Vol 94 (4) ◽  
pp. 589-595 ◽  
Author(s):  
Asim Mahmood ◽  
Dunyue Lu ◽  
Yi Li ◽  
Jae Li Chen ◽  
Michael Chopp

Object. The authors tested the hypothesis that intracranial bone marrow (BM) transplantation after traumatic brain injury (TBI) in rats provides therapeutic benefit. Methods. Sixty-six adult Wistar rats, weighing 275 to 350 g each, were used for the experiment. Bone marrow prelabeled with bromodeoxyuridine (BrdU) was harvested from tibias and femurs of healthy adult rats. Other animals were subjected to controlled cortical impact, and BM was injected adjacent to the contusion 24 hours after the impact. The animals were killed at 4, 7, 14, or 28 days after transplantation. Motor function was evaluated both before and after the injury by using the rotarod test. After the animals had been killed, brain sections were examined using hemotoxylin and eosin and immunohistochemical staining methods. Histological examination revealed that, after transplantation, BM cells survived, proliferated, and migrated toward the injury site. Some of the BrdU-labeled BM cells were reactive, with astrocytic (glial fibrillary acid protein) and neuronal (NeuN and microtubule-associated protein) markers. Transplanted BM expressed proteins phenotypical of intrinsic brain cells, that is, neurons and astrocytes. A statistically significant improvement in motor function in rats that underwent BM transplantation, compared with control rats, was detected at 14 and 28 days posttransplantation. Conclusions. On the basis of their findings, the authors assert that BM transplantation improves neurological outcome and that BM cells survive and express nerve cell proteins after TBI.


2002 ◽  
Vol 96 (1) ◽  
pp. 97-102 ◽  
Author(s):  
Roberto Imberti ◽  
Guido Bellinzona ◽  
Martin Langer

Object. The aim of this study was to investigate the effects of moderate hyperventilation on intracranial pressure (ICP), jugular venous oxygen saturation ([SjvO2], an index of global cerebral perfusion), and brain tissue PO2 (an index of local cerebral perfusion). Methods. Ninety-four tests consisting of 20-minute periods of moderate hyperventilation (27–32 mm Hg) were performed on different days in 36 patients with severe traumatic brain injury (Glasgow Coma Scale score ≤ 8). Moderate hyperventilation resulted in a significant reduction in average ICP, but in seven tests performed in five patients it was ineffective. The response of SjvO2 and brain tissue PO2 to CO2 changes was widely variable and unpredictable. After 20 minutes of moderate hyperventilation in most tests (79.8%), both SjvO2 and brain tissue PO2 values remained above the lower limits of normality (50% and 10 mm Hg, respectively). In contrast, in 15 tests performed in six patients (16.6% of the studied population) brain tissue PO2 decreased below 10 mm Hg although the corresponding SjvO2 values were greater than 50%. The reduction of brain tissue PO2 below 10 mm Hg was favored by the low prehyperventilation values (10 tests), higher CO2 reactivity, and, possibly, by lower prehyperventilation values of cerebral perfusion pressure. In five of those 15 tests, the prehyperventilation values of SjvO2 were greater than 70%, a condition of relative hyperemia. The SjvO2 decreased below 50% in four tests; the corresponding brain tissue PO2 values were less than 10 mm Hg in three of those tests, whereas in the fourth, the jugular venous O2 desaturation was not detected by brain tissue PO2. The analysis of the simultaneous relative changes (prehyperventilation — posthyperventilation) of SjvO2 and brain tissue PO2 showed that in most tests (75.5%) there was a reduction of both SjvO2 and brain tissue PO2. In two tests moderate hyperventilation resulted in an increase of both SjvO2 and brain tissue PO2. In the remaining 17 tests a redistribution of the cerebral blood flow was observed, leading to changes in SjvO2 and brain tissue PO2 in opposite directions. Conclusions. Hyperventilation, even if moderate, can frequently result in harmful local reductions of cerebral perfusion that cannot be detected by assessing SjvO2. Therefore, hyperventilation should be used with caution and should not be considered safe. This study confirms that SjvO2 and brain tissue PO2 are two parameters that provide complementary information on brain oxygenation that is useful to reduce the risk of secondary damage. Changes in SjvO2 and brain tissue PO2 in opposite directions indicate that data obtained from brain tissue PO2 monitoring cannot be extrapolated to evaluate the global cerebral perfusion.


1978 ◽  
Vol 48 (2) ◽  
pp. 169-172 ◽  
Author(s):  
Lawrence F. Marshall ◽  
Randall W. Smith ◽  
L. Andrew Rauscher ◽  
Harvey M. Shapiro

✓ There is little information as to the optimal use of mannitol. To determine the dose-response relationship, the osmotic gradient required, and the time course of intracranial pressure (ICP) reduction produced by mannitol, eight patients with acute head injury were studied in whom ICP was monitored with a ventriculostomy and found to be elevated. Ventilation was controlled to a pCO2 of 25 ± 3 mm Hg and all were paralyzed with Pavulon. None had received barbiturates. Before mannitol administration the intracranial volume-pressure response was determined. Mannitol was administered as a bolus of 0.25 gm/kg, 0.5 gm/kg, and in six patients, 1 gm/kg, separated by at least 8 hours. In all patients the ICP reduction with 0.25 gm/kg (41.3 ± 10.2 mm Hg→16.4 ± 5.6, p < 0.01) was equivalent to that achieved with the larger doses. Serum osmolality rises of 10 mOsm or more were associated with a reduction in ICP. Much smaller doses than those previously recommended were effective in reducing the ICP acutely, although at 5 hours there was a trend toward persistent reduction when the larger dose is used. This trend was small and indicates that smaller and more frequent doses are as effective in reducing the ICP while avoiding the risk of osmotic disequilibrium and severe dehydration.


2002 ◽  
Vol 97 (1) ◽  
pp. 84-92 ◽  
Author(s):  
Paul M. Vespa ◽  
W. John Boscardin ◽  
David A. Hovda ◽  
David L. McArthur ◽  
Marc R. Nuwer ◽  
...  

Object. Early prediction of outcomes in patients after they suffer traumatic brain injury (TBI) is often nonspecific and based on initial imaging and clinical findings alone, without direct physiological testing. Improved outcome prediction is desirable for ethical, social, and financial reasons. The goal of this study was to determine the usefulness of continuous electroencephalography (EEG) monitoring in determining prognosis early after TBI, while the patient is in the intensive care unit. Methods. The authors hypothesized that the reduced percentage of alpha variability (PAV) in continuous EEG tracings indicates a poor prognosis. Prospective continuous EEG monitoring was performed in 89 consecutive patients with moderate to severe TBI (Glasgow Coma Scale [GCS] Scores 3–12) from 0 to 10 days after injury. The PAV was calculated daily, and the time course and trends of the PAV were analyzed in comparison with the patient's Glasgow Outcome Scale (GOS) score at the time of discharge. In patients with GCS scores of 8 or lower, a PAV value of 0.1 or lower is highly predictive of a poor outcome or death (positive predictive value 86%). The determinant PAV value was obtained by Day 3 after injury. Persistent PAV values of 0.1 or lower over several days or worsening of the PAV to a value of 0.1 or lower indicated a high likelihood of poor outcome (GOS Scores 1 and 2). In comparison with the combination of traditional initial clinical indicators of outcome (GCS score, pupillary response to light, patient age, results of computerized tomography scanning, and early hypotension or hypoxemia), the early PAV value during the initial 3 days after injury independently improved prognostic ability (p < 0.01). Conclusions. Continuous EEG monitoring performed with particular attention paid to the PAV is a sensitive and specific method of prognosis that can indicate outcomes in patients with moderate to severe TBI within 3 days postinjury.


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