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)

Pharmacological treatment for cerebral ischemia and cerebral vasospasm following subarachnoid hemorrhage (SAH) cannot attain sufficiently high concentrations of the drugs in the cerebrospinal fluid (CSF) without precipitating systemic side effects. We recently developed a liposomal drug delivery system for intrathecal application that can maintain effective concentrations of cerebral vasodilator, fasudil, in the CSF. A single intrathecal injection of liposomal fasudil could maintain a therapeutic drug concentration in the CSF over a period time due to their sustained-release property, significantly decreasing infarct size in a rat model of acute ischemia and reducing vasoconstriction of the rat and dog basilar artery in a model of SAH. In this review, we are introducing our new less-invasive intrathecal drug delivery system that provides an alternative and safe method to deliver therapeutic agents.
 ...
PMID:Safe and efficient drug delivery system with liposomes for intrathecal application of an antivasospastic drug, fasudil. 1650 35

Clazosentan, an endothelin ETA antagonist, is under development by Actelion (formerly Axovan), under license from F Hoffman-La Roche, for the potential prevention of cerebral infarction and ischemia induced by cerebral vasospasm following subarachnoid hemorrhage. Results from the phase IIb portion of a phase IIb/III clinical study are expected in the first half of 2006.
 ...
PMID:Clazosentan (Actelion). 1655 88

The most frequent indication for Calcium Channel Blockers (CCBs) is their use as antihypertensive agents for primary or secondary stroke prevention. Hypertension contributes to virtually all mechanisms of stroke, of atherothrombotic, lacunar, cardioembolic and intraparenchymal hemorrhage types. In comparison with the rather univocal mechanisms underlying coronary artery or peripheral artery disease, the variable mechanisms of stroke are the main reason explaining not only the different impact of vascular risk factors, but also the different effects of drugs given for prevention. In an acute stroke setting, lowering blood pressure is potentially harmful, especially if it is carried out using short-acting dihydropyridine derivatives. Some CCBs, such as nicardipine, are preferred in certain conditions (including acute thrombolysis). In stroke, CCBs may also play a role as neuroprotectants. Then twofold effect--against vessel wall changes and as neuroprotectants (after ischemia or degenerative insults)--make this class of drugs of interest for their possible application in the setting of dementias, particularly that of vascular dementia. Some CCBs have been tested and are of benefit when used for preventing or treating cerebral vasospasm after subarachnoid hemorrhage. CCBs must be considered effective in preventing stroke in hypertensive patients. In comparison with other antihypertensive agents, their effects are similar to or even better than those exerted by other drugs. This may be due to the fact that stroke includes different types, with differing underlying pathophysiological mechanisms. The anti-atherosclerotic properties of CCBs may be useful in preventing the atherothrombotic type of stroke at the large pre-cerebral artery level. Dihydropyridinic derivatives may play a selective role in relation to small-vessel disease of the brain, which leads to multiple stroke-associated conditions, including lacunar infarct, intra-cerebral hemorrhage and subcortical vascular dementia. Oral nimodipine is recommended in the prevention/treatment of cerebral vasospasm following subarachnoid hemorrhage (SAH). CCBs, particularly nimodipine, may be of some benefit in vascular or mixed degenerative and vascular dementia or, taking into account subtypes, more selectively in subcortical vascular dementia. In this setting, CCBs may contribute toward reducing the risk of recurrent stroke in patients who are usually at high risk of recurrence.
 ...
PMID:Calcium channel blockers and stroke. 1664 Jan 70

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

Monitoring of cerebral blood flow (CBF) is an essential part in the early diagnosis of cerebral vasospasm following aneurysmal subarachnoid hemorrhage (SAH). Several methods have been established to monitor cerebral perfusion in these patients. During last few years, a new sonographic approach has been introduced, the so called 'angle independent ultrasound system' for monitoring volume flow in the internal carotid artery (ICA). The angle independent Doppler ultrasound system Quantix ND (Cardiosonix Ltd, Israel) determines the diameter of the ICA as well as the velocity of blood flow in the extracranial part of this vessel. Thus, a determination of the global CBF in the anterior circulation can be achieved. Aim of our study was to compare the Quantix ND system and the commonly used transcranial Doppler sonography (TCD) in patients suffering from aneurysmal SAH. We included 11 patients (eight female and three male; Hunt and Hess I-V) and performed post-operatively/post-interventionally daily measurement of blood flow volume in the ICA, and determined the blood flow velocity in middle and anterior cerebral artery (MCA and ACA) with TCD. Six patients post-operatively/post-interventionally developed cerebral vasospasm, resulting in ischemia and territorial infarction. Three patients were chosen as case studies. In contrast to the TCD, we found a strong significant correlation of blood flow volume with Quantix ND in the ICA and the occurrence of cerebral infarction (p<0.001). These preliminary data justify further investigation of this angle independent Doppler ultrasound device. We postulate that this new tool might be effective for monitoring the CBF in the critical post-operative/post-interventional interval following aneurysmal SAH.
 ...
PMID:Doppler ultrasound measurement of blood flow volume in the extracranial internal carotid artery for evaluation of brain perfusion after aneurysmal subarachnoid hemorrhage. 1743 6

Cerebral vasospasm is an important syndrome that afflicts 30% of patients in the aftermath of, and secondary to, subarachnoid hemorrhage. Starting approximately one week after the hemorrhage, the condition worsens the prognosis of the hemorrhage significantly. Apart from general supportive care, no treatment exists for cerebral vasospasm. During the past 50 years, it was thought that the ischemia that signifies poor outcome is more or less exclusively caused by arterial narrowing. However, this idea has recently been challenged by the failure of the drug clazosentan to improve patient outcome, despite reversing vasoconstriction. In this article, we discuss the opinion that factors other than vasoconstriction are important in the pathophysiology and prognosis of cerebral vasospasm. Such factors include global ischemia, disruption of the blood-brain barrier, activation of apoptotic and inflammatory pathways, and cortical spreading depression.
 ...
PMID:Cerebral vasospasm: looking beyond vasoconstriction. 1746 86

Delayed neurological deficit occurs among 30% of patients after aneurysmal subarachnoid haemorrhage, mainly related to cerebral vasospasm. The early detection of cerebral ischemia remains problematic. Conventional cerebral monitoring (as intracranial pressure and cerebral perfusion pressure) appears to be insufficient, because cerebral ischemia may occur without elevated intracranial pressure. Global cerebral monitoring as venous jugular oxygen saturation are useful for regional monitoring. Local monitoring as oxygen tissue partial pressure (PtiO2) and microdialysis are sensible for brain ischemia detection, but may also ignore episodes occurring in non-monitored brain area. For the detection of most episodes of brain ischemia, several monitoring system should be use performing a multimodal intracerebral monitoring. Brain microdialysis and oxygen tissue partial pressure are promising monitoring system.
 ...
PMID:[Intracerebral monitoring of a patient with vasopasm]. 1793 65

The causes of postoperative cardiovascular disturbances in neurosurgical patients include direct cardiac neurogenic effects, clinical situations where brain tissue is underperfused, and hyperdynamic states. EKG and echographic abnormalities are common in subarachnoid hemorrhage where cardiac troponin I is the most useful predictor of cardiac risk after SAH. Neurogenic pulmonary edema is short lived and often resolves with resolution of the neurologic problem. In traumatic brain injury, where areas of ischemia co-exist with luxury perfusion, advanced hemodynamic monitoring and prevention of jugular venous desaturation best avoid secondary brain injury and achieve optimal neurologic outcome. Induced hypertension improves blood flow through vessels compromised by cerebral stenting, angioplasty, microcatheters, thrombolysis, carotid clamping, intracranial bypass and cerebral vasospasm. Hyperdynamic lesions include vascular breakthrough after elimination of cerebral arteriovenous malformations, but also emergence hypertension and hyperemia. Pharmacologic agents and adjunctive measures are effective in controlling both the systemic and the cerebral circulation.
 ...
PMID:Cardiovascular therapy of neurosurgical patients. 1828 33

Eclampsia is characterized by generalized convulsions in pregnant women with hypertension and proteinuria. Little is known about what triggers the convulsions in this syndrome. The prevailing view is that convulsions are caused by cerebral vasospasm and cerebral edema. However, many important clinical findings argue against cerebral edema or hypertensive encephalopathy as the sole causes of convulsions in eclampsia. The utero-placental ischemia causes the release of certain molecules such as neurokinin B, inflammatory cytokines, endothelins, and tissue plasminogen activator. These molecules stimulate excitatory neuronal receptors and alter neuronal excitability, synaptic transmission, and neuronal survival independent of any vascular effects. Highlighting the neuromodulatory and the convulsive effects of each of these molecules which are elevated in pre-eclampsia, offers a new perspective on the mechanisms of convulsions in eclampsia.
 ...
PMID:Mechanisms of convulsions in eclampsia. 1884 Mar 93

The authors describe the case of a 13-year-old boy who presented with an intraventricular hemorrhage caused by a left trigonal arteriovenous malformation. After an initial recovery, the patient experienced complete right-sided paresis on posthemorrhage Day 6. Severe cerebral vasospasm was found on MR angiography and confirmed on conventional cerebral angiography. Intraarterial nicardipine injection and balloon angioplasty were successfully performed with improved vasospasm and subsequent neurological recovery. Cerebral vasospasm should be considered in the differential diagnosis for neurological deterioration following an arteriovenous malformation hemorrhage, and aggressive treatment can be administered to prevent ischemia and further neurological deficits.
 ...
PMID:Successful treatment of severe cerebral vasospasm following hemorrhage of an arteriovenous malformation. Case report. 1977 12


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>