Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Focal arterial infarction in the full-term newborn is an important cause of acquired cerebral lesions in the perinatal period. Clinical motor seizures, most often unifocal, are the nearly constant disclosing symptom confirmed by focal EEG abnormalities. A multifactorial physiopathology is usual, including genetic and perinatal environmental factors. In the past decade, various acquired or genetic thrombophilias have been discussed as risk factors. For several of the involved mechanisms, the excitotoxic cascade could represent a common final pathway leading to neuronal cell death. Early magnetic resonance imaging studies and EEG help to identify the newborns with strokes who are likely to develop hemiplegia and disabilities at school. Protection of the human fetal brain remains difficult, since the triggering factor initiating the excitotoxic cascade is rarely observed. Treatment of seizures is nevertheless necessary, because it seems that they accelerate anoxia-induced neuronal death in animal models of focal hypoxic ischemia.
 ...
PMID:Fetal and neonatal cerebral infarcts. 1127 58

Cerebral infarction results in multiple symptoms including hemiplegia and cognitive disturbances. The central nervous system has a limited capacity for self-repair, thus there is a great interest in the possibility of repairing the central nervous system by neural transplantation. Two different types of cerebral infarction model are well investigated for neural transplantation. Several kinds of donor cells have been used to try to restore the brain damage after ischemic insult. Reconstruction of neural circuits by transplantation is an ideal goal for the treatment of cerebral infarction, but trophic action of transplantation is also expected. Amelioration of ischemia-induced brain damage and recovery of neural dysfunction are documented. However, there are several factors and problems to be solved for clinical application.
 ...
PMID:[Neural transplantation for cerebral ischemia/infarction--the present situation and prospects]. 1185 35

Many factors contribute to the severity of neuronal cell death and the functional outcome in stroke. We describe an embolic model of focal cerebral ischemia in the rat that does not require craniotomy and is compatible with continuous measurement of regional CBF using multichannel laser Doppler flow (LDF) technique. Either a 22 microliters (large lesion) or 11 microliters (small lesion) bolus of viscous silicone was injected cephalad into the internal carotid artery. Upon injection, LDF decreased abruptly, most severely in the parietal cortex (-74% +/- 5%) in the large lesion and in the occipital cortex (-69% +/- 10%) in the small lesion model. Over the first hour, post-embolization LDF improved in most areas (e.g. -48% +/- 9% parietal, large lesion) but declined in the small lesion group in the occipital region (-81% +/- 8%). CBF measured by [C]14-IAP autoradiography 1 h post-embolization in the large lesion model demonstrated near-hemispheric ischemia (70% of hemisphere) with sparing of cingulate cortex. Autoradiography demonstrated that ischemia in the small lesion was largely cortical. Light microscopy of brains embolized with 11 microliters of dyed silicone showed filling of pial vessels with no silicone in the Circle of Willis or parenchyma. No animals in the large lesion group survived 24 h. Thirteen of 15 animals in the small lesion group survived for two weeks with resolution of initial hemiplegia, ocular asymmetry and weight loss. Hematoxylin-eosin staining two weeks post-embolization showed signs of severe hypoxia and infarction. In conclusion, the intracarotid silicone embolization technique produces a titrable, reproducible permanent ischemic injury by blocking perfusion in the pial circulation, and is amenable to multisite monitoring with laser Doppler flowmetry. The smaller embolus produces cortical infarction with high rate of survival and neurological recovery.
 ...
PMID:Focal cerebral ischemia in rats produced by intracarotid embolization with viscous silicone. 1187 3

We developed a method of causing strong ischemic insult only in vulnerable nerve cells, such as hippocampal cells, without causing hemiplegia or difficulty in moving, by repeating cerebral ischemia for a brief time with a short interval periods. The rats subjected to 10 min of cerebral ischemia exhibited no impairment of spatial cognition at the test trial 7 days after final reperfusion. However, when the 10 min ischemia was repeated twice with a 1 hr interval, the rats exhibited a significant decrease in number of correct choices and increase in number of errors. Three times of repeated cerebral ischemia also induced a significant decrease in the number of correct choices and increase in the number of errors, but there were some rats showing motor difficulty. Cell death was typically observed in the CA1 layer of the hippocampus of rats subjected twice to 10 min of cerebral ischemia. Hippocampal and cortical acetylcholine (ACh) release weas transiently increased during the first and second 10 minutes of ischemia and normalized immediately after recirculation; thereafter, ACh release from these areas gradually decreased and showed a significantly low level at 7 days after recirculation. These results suggest that the repeated cerebral ischemia-induced impairment of spatial memory may be due to the dysfunction of hippocampal and cortical ACh systems and hippocampal cell death. The repeated cerebral ischemia model which produces cell death and ACh dysfunction in the hippocampus is thought to be useful for evaluating new drugs for the treatment of cerebrovascular dementia.
 ...
PMID:Repeated cerebral ischemia induced hippocampal cell death and impairments of spatial cognition in the rat. 1246 2

We report the case of a 67 year old patient admitted at our institution for acute onset of left hemiplegia. MRI was done 2 h 30 after symptom onset. Diffusion weighted images showed a hyperintense lesion in the right basal ganglia region with restricted apparent diffusion coefficient (ADC=428. 10(-6) mm(2)/s), a 50% decrease in value compared to the normal left side, consistent with acute ischemia. The lesion was hyperintense and moderately heterogeneous at FLAIR imaging, best seen on echo planar T2W images, with hypointense rim consistent with magnetic susceptibility artifact. The appearance and location of the lesion suggested the possibility of hematoma, which was confirmed at CT. Interpretation of ADC values must be performed in correlation with results at imaging including sequences sensitive to magnetic susceptibility artifacts such as echo planar T2*W and T2W sequences in order to exclude the possibility of underlying hematoma.
 ...
PMID:[Intracerebral hematoma associated with reduced apparent diffusion coefficient mimicking acute stroke]. 1262 92

A series of 17 patients aged from 9 months to 32 years with refractory epilepsy due to hypothalamic hamartoma were treated by total removal (one case) and disconnection (16 cases) between 1997 and 2002. The mean age at seizure onset was 16 months. Sixteen patients had gelastic seizures, 14 had partial seizures and three had generalized tonic-clonic seizures. The mean seizure frequency was 21 per day. Four patients had borderline intelligence quotient and the others were mentally retarded. Five patients presented with precocious puberty, one with acromegaly, and four suffered from obesity. Brain magnetic resonance imaging, performed at least twice in each patient, showed the hamartoma as a stable homogeneous interpeduncular mass implanted either on the mammilary tubercle or on the wall of the third ventricle with variable extension to the bottom. Ictal single photon emission computed tomography, performed in four patients, showed hyperperfusion within the hamartoma in two patients. Twenty-five operations were performed in the 17 patients. The first patient underwent total removal of the hamartoma, whereas the following 16 patients underwent disconnection through open surgery (14 procedures) and/or endoscopy (9 procedures). Eight patients became seizure-free, one patient had only brief gelastic seizures, and eight patients were dramatically improved with a mean follow up of 18.6 months (8 days to 43 months). Surgery was safe in all but two patients: the first patient had transient hemiplegia and the third cranial nerve paresis, and the other developed hemiplegia due to ischemia of the middle cerebral artery territory. The quality of life, and behavior and school performance were greatly improved in most patients. Our series illustrates the feasibility and relative safety of disconnection surgery for hypothalamic hamartomas with seizure relief in 53% of patients and dramatic improvement in the others. Surgical observations led us to propose a new anatomical classification according to the anatomical relationship between the hamartoma and the adjacent hypothalamus and third ventricle. Endoscopic disconnection seems to be a very safe way to treat hamartomas in intraventricular locations.
 ...
PMID:Disconnecting surgical treatment of hypothalamic hamartoma in children and adults with refractory epilepsy and proposal of a new classification. 1262 81

The value of motor evoked potentials (MEPs) as an intraoperative neurophysiological monitoring tool for detecting selective subcortical ischemia of the motor pathways during intracerebral aneurysm repair is described and the use of such measures to predict postoperative motor status is discussed. The authors present the case of a 64-year-old woman in whom there was an incidental finding of two right middle cerebral artery (MCA) aneurysms. During the aneurysm clipping procedure, an intraoperative MEP loss in the left abductor pollicis brevis and tibial anterior muscles occurred during an attempt at permanent clip placement. There were no concurrent changes in somatosensory evoked potentials. Postoperatively, the patient demonstrated a left hemiplegia with intact sensation. A computerized tomography scan revealed an infarct in the anterior division of the MCA territory, including the posterior limb of the internal capsule. In this patient, intraoperative neurophysiological monitoring with MEPs has been shown to be a sensitive tool for indicating subcortical ischemia affecting selective motor pathways in the internal capsule. Therefore, intraoperative loss of MEPs can be used to predict postoperative motor deficits.
 ...
PMID:Neurophysiological criteria for intraoperative prediction of pure motor hemiplegia during aneurysm surgery. Case report. 1295 48

The aim of this study was to evaluate femoral artery cannulation in Stanford type A aortic dissection operations. Between March 1994 and December 2001, 88 patients with Stanford type A aortic dissection underwent surgery with cardiopulmonary bypass and perfusion through the femoral artery; 31 of them had deep-hypothermic circulatory arrest. False lumen perfusion was detected in 8 patients (9.1%). There were 4 (4.5%) cerebral events: 2 patients had diffuse cerebral injury, with one death; and 2 patients had hemiplegia, with one death. Six patients (8.0%) had delayed incision healing, with local infection in one. There was no lower extremity ischemia associated with femoral artery cannulation. It was concluded that retrograde perfusion through the femoral artery was effective for repair of aortic dissection, with a low risk of those cerebral events associated with a high mortality rate.
 ...
PMID:Femoral artery cannulation in Stanford type A aortic dissection operations. 1643 16

This is the case report of a 44-year-old woman presented with an acute stroke immediately after electroconvulsive therapy (ECT). The patient had no significant medical history other than chronic depression. She was taking sertraline, and she had had multiple previous ECT treatments without any complications. While being monitored in the recovery room within 10 minutes after the last ECT session, she was found to have sudden onset of left-sided flaccid hemiplegia and numbness along with slurred speech. On arrival to our hospital, she was found to have flaccid hemiplegia on the left side involving the face, arm, and leg (face and arm more than the leg involvement), severe dysarthria, and mild neglect syndrome (National Health Institute Stroke Scale of 14). Noncontrast computed tomography (CT) of the head showed no signs of early ischemia, and iodine contrast CT angiography revealed right middle cerebral artery (MCA) (distal M1 segment) clot. Patient received intravenous recombinant tissue plasminogen (rt-PA) at 2.5 hours after the onset of symptoms, and then a total of 3.0 mg of intra-arterial (IA) rt-PA. Angiography at the end of the procedure showed successful recanalization of the M1 segment and normal vessel caliber with adequate distal flow. After the procedure, the patient made rapid improvements in all of her initial symptoms during the first 24 hours. An extensive stroke workup failed to reveal any cause of the stroke, including usual stroke and hypercoagulable risk factors. This was an acute embolic stroke immediately following an ECT, and without the aggressive thrombolytic therapy, the patient's outcome would have been poor because there was an M1 segment clot with a major MCA syndrome with relatively high National Institute of Health Stroke Scale. The neurological side effect profile of ECT is reported to be minimal with most common symptoms being headache, disorientation, and memory complaints. There is no clear cause-and-effect relationship in this case, and the stroke after ECT is extremely rare. In such rare event of stroke while receiving ECT, there is an effective treatment available using both intravenous and IA thrombolysis as reported in this case.
 ...
PMID:Acute embolic stroke after electroconvulsive therapy. 1663 11

This study investigated nonspecific behaviors as early indications of vasospasm following subarachnoid hemorrhage. Although symptoms of vasospasm (e.g., lowered level of consciousness, focal deficits such as hemiplegia or aphasia), are well recognized, the significance of early appearance of nonspecific symptoms such as restlessness, unusual behaviors, and impulsive behavior has not been investigated in detail. The study design included descriptive quantitative elements and a small qualitative component. Nonspecific behaviors were recorded, and the prevalence of those behaviors in individuals developing vasospasm was noted. Of 60 participants, 31 developed vasospasm; 24 of the 31 initially presented with nonspecific behaviors (p < .0001). Early detection of cerebral vasospasm allows prompt intervention and treatment, with the goal of preventing further ischemia or infarction.
 ...
PMID:Nonspecific behaviors as early indications of cerebral vasospasm. 1723 10


<< Previous 1 2 3 4 5 6 Next >>