Transforming growth factor-alpha acting at the epidermal growth factor receptor reduces infarct volume after permanent middle cerebral artery occlusion in rats.
(1/1215)
Transforming growth factor-alpha (TGF-alpha) is a ligand for the epidermal growth factor (EGF) receptor (EGFR), and is more abundant than EGF in the brain. The authors studied whether administration of exogenous TGF-alpha into the brain can protect neurons against ischemia in a model of permanent middle cerebral artery (MCA) occlusion in the rat, and whether any effect of TGF-alpha was mediated by EGFR by administering 4,5-dianilinophthalimide (DAPH), a protein-tyrosine kinase inhibitor with high selectivity for EGFR. Rats received either TGF-alpha (10 or 25 ng), DAPH (100 ng), DAPH plus TGF-alpha (25 ng), or vehicle in the ipsilateral first ventricle. Drugs were administered twice: 30 minutes before and 30 minutes after MCA occlusion, and infarct volume was evaluated 24 hours later. Transforming growth factor-alpha at the dose of 25 ng caused a statistically significant reduction of infarct volume (60%) in relation to ischemic rats administered vehicle. This reduction was no longer seen when TGF-alpha was administered in combination with DAPH. The present results show that TGF-alpha can protect neurons from ischemic damage, and that this effect is mediated by EGFR. It is suggested that activation of EGFR-mediated intracellular signalling pathways contributes to the survival of neural cells susceptible to ischemic injury. (+info)
Computerised axial tomography in patients with severe migraine: a preliminary report.
(2/1215)
Patients suffering from severe migraine, usually for many years, have been examined by the EMI scanner between attacks. Judged by criteria validated originally by comparison with pneumoencephalography, about half of the patients showed evidence of cerebral atrophy. Perhaps of more significance than generalised atrophy was the frequency of areas of focal atrophy and of evidence of infarction. (+info)
Two similar cases of encephalopathy, possibly a reversible posterior leukoencephalopathy syndrome: serial findings of magnetic resonance imaging, SPECT and angiography.
(3/1215)
Two young women who had encephalopathy that resembled reversible posterior leukoencephalopathy syndrome are presented. The brain magnetic resonance imaging (MRI) of these patients exhibited similar T2-high signal lesions, mostly in the white matter of the posterior hemispheres. Xe-SPECT during the patients' symptomatic period showed hypoperfusion in the corresponding areas, and angiography demonstrated irregular narrowing of the posterior cerebral artery. Clinical manifestations subsided soon after treatment, and the abnormal radiological findings also were almost completely resolved. Thus, we concluded that transient hypoperfusion followed by ischemia and cytotoxic edema might have had a pivotal role in these cases. (+info)
Significance of acute cerebral swelling in patients with sylvian hematoma due to ruptured middle cerebral artery aneurysm, and its management.
(4/1215)
A retrospective study of 75 patients treated surgically for ruptured middle cerebral artery (MCA) aneurysm within 48 hours evaluated clinical grade at admission, secondary development and management of cerebral swelling associated with space-occupying hematoma, cerebral infarction caused by vasospasm, development of hydrocephalus, and clinical outcome. Clinical grade at admission was significantly better in patients without than in those with hematoma (p < 0.01). Twenty-seven patients with sylvian hematoma caused by ruptured MCA aneurysm often developed ipsilateral cerebral swelling in the early period after subarachnoid hemorrhage. Seventeen of these patients developed serious cerebral swelling and received barbiturate therapy. Nine of these 17 patients had good outcome, but six patients died of cerebral swelling. The incidence of hydrocephalus was significantly higher in patients with than in those without hematoma (p < 0.01). The incidence of infarction was more pronounced in patients with sylvian hematoma. Clinical outcome was significantly better in patients without than in those with sylvian hematoma (p < 0.01). Development of cerebral swelling in patients with sylvian hematoma due to ruptured MCA aneurysm has a significant effect on outcome, and improvements in management are required. (+info)
Cerebral blood flow in the monkey after focal cryogenic injury.
(5/1215)
A focal cryogenic lesion was made in the left superior frontal gyrus of the anesthetized macaque brain. Cerebral blood flow (CBF) was determined by the hydrogen clearance technique before and during the 4 hours following trauma. Local CBF in tissue adjacent to the lesion increased in the first half hour after the lesion was made and then decreased during the ensuing 3 1/2 hours. Local CBF in the contralateral superior frontal gyrus, as well as total CBF and oxygen consumption, were unchanged by cryogenic trauma. The spread of vasogenic edema into uninjured tissue probably accounts for the observed decrease in local CBF. This experimental model may assist in discovering therapy to alter favorably the spatial and temporal profile of pathologic CBF changes in tissue surrounding an acute lesion of the brain. (+info)
Abrupt exacerbation of acute subdural hematoma mimicking benign acute epidural hematoma on computed tomography--case report.
(6/1215)
A 75-year-old male was hit by a car, when riding a bicycle. The diagnosis of acute epidural hematoma was made based on computed tomography (CT) findings of lentiform hematoma in the left temporal region. On admission he had only moderate occipitalgia and amnesia of the accident, so conservative therapy was administered. Thirty-three hours later, he suddenly developed severe headache, vomiting, and anisocoria just after a positional change. CT revealed typical acute subdural hematoma (ASDH), which was confirmed by emergent decompressive craniectomy. He was vegetative postoperatively and died of pneumonia one month later. Emergent surgical exploration is recommended for this type of ASDH even if the symptoms are mild due to aged atrophic brain. (+info)
Epilepsy after two different neurosurgical approaches to the treatment of ruptured intracranial aneurysm.
(7/1215)
One-hundred-and-fifty-two patients who underwent surgery for intracranial aneurysm were studied to determine the incidence of postoperative epilepsy in relation to the site of the aneurysm and the type of surgical approach. The overall incidence of epilepsy was 22%. Of the 116 patients treated by the intracranial approach 27.5% developed epilepsy, in contrast with only 5% of the 36 patients who had carotid artery ligation in the neck. Epilepsy occurred most frequently (35%) with middle cerebral artery aneurysms, especially if moderate or severe operative trauma was sustained and there was postoperative dysphasia. (+info)
Glial and capillary density of the pontine white matter in swelling and atrophy.
(8/1215)
A total of 48 autopsied brains were morphometrically examined for the relation between pontine geometry and structural parameters. In each case, the numerical density of neuroglial cells Nv(G) and the linear density of capillary network Lv(C) of the pontine white matter were determined stereologically from the counts of glial nuclear profiles and capillary transections per constant area of a histological section with a constant thickness. It was revealed that in general the glial numerical density increased with advancing atrophy and decreased with increasing swelling, whereas the capillary linear density remained fairly constant especially in the advanced stage of brain swelling. Further analysis of this relation using a model of pontine geometry has made it clear that the total capillary length in the swollen white matter increases probably at the expense of the capillary caliber as swelling advances. The changes in the ratio Lv(C)/Nv(G) under pathological conditions are emphasized and possible utility of classifying stages of acute brain swelling from a viewpoint of microvascular dimension is suggested. (+info)