PubMed HealthSearch

Biomedical subjects

W Hacke

Publications and source records attributed to W Hacke.

At least 19 recordsLinked to original sources

Induction of FOS and JUN proteins after focal ischemia in the rat: differential effect of the N-methyl-D-aspartate receptor antagonist MK-801.

FOS and JUN proteins are transcription factors thought to be involved in coupling neuronal excitation to target gene expression. Cortical infarction of consistent size and location was produced by irradiating the rat brain with Xenon light through the intact skull for 20 min following systemic injection of the photo-sensitizing dye, rose bengal. To investigate the time course and distribution pattern of five cellular immediate early gene (IEG)-encoded proteins after focal ischemia, the expression of c-FOS, FOS B, c-JUN, JUN B and JUN D was studied immunocytochemically in sham-operated control animals and at different postischemic time intervals up to 24 h. A separate group of animals was pretreated with the non-competitive N-methyl-D-aspartate (NMDA) antagonist MK-801. Photochemically induced focal ischemia caused a rapid induction of FOS and JUN proteins in the entire ipsilateral cortex apart from the ischemic focus. Immunoreactivity in the ipsilateral subcortical gray and white matter and in the entire contralateral hemisphere was indistinguishable from control animals. Individual IEG-encoded proteins were sequentially induced with increased levels of immunoreactivity persisting for different time periods up to 24 h. c-FOS, FOS B, c-JUN and JUN B exhibited a characteristic distribution pattern as reflected by different staining intensities in individual cortical layers. The rapid IEG induction in the entire ipsilateral sensorimotor and limbic structure-associated cortices after photochemically induced infarction most likely reflects spreading depression caused by ischemia and mediated by NMDA receptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Untreated neuroborreliosis: Bannwarth's syndrome evolving into acute schizophrenia-like psychosis. A case report.

In general, meningopolyradiculitis (Bannwarth's syndrome, stage 2 of neuroborreliosis) follows a predictable monophasic self-limiting course. In contrast, we report the case of a patient with an untreated meningopolyradiculitis which evolved into acute schizophrenia-like psychosis due to persistent infection with Borrelia burgdorferi. The psychosis resolved within 1 week of treatment with ceftriaxone. This case shows that the usually benign monophasic meningopolyradiculitis may progress to severe CNS complications, which may have implications on current pathophysiological beliefs.

Acute Disease

Safety and efficacy of intravenous tissue plasminogen activator and heparin in acute middle cerebral artery stroke.

BACKGROUND AND PURPOSE: There is little reported of the safety and efficacy of high-dose intravenous recombinant tissue plasminogen activator (alteplase) in combination with heparin anticoagulation in patients presenting with acute ischemic stroke. METHODS: Thirty-two patients with severe hemispheric stroke syndrome caused by angiographically proven middle cerebral artery and/or intracranial internal carotid artery occlusion were treated with 100 mg alteplase by intravenous infusion over 90 minutes within a mean +/- SD of 226 +/- 68 minutes after symptom onset. Recanalization was assessed by digital subtraction angiography in all patients immediately after treatment and by transcranial Doppler monitoring (n = 30) and/or a third angiogram (n = 5) 12-24 hours later. RESULTS: Complete or partial reperfusion was observed in 11 patients (34%) 90 minutes after the initiation of alteplase infusion and in 17 patients (53%) within 12-24 hours. Hemorrhagic infarction without clinical deterioration was detected by follow-up computed tomography in nine patients (28%). Fatal parenchymal hemorrhage occurred in three patients (9%) with huge middle cerebral artery infarcts. Serious hemorrhage from the puncture site occurred in two patients (6%). Good clinical outcome correlated with reperfusion (p less than 0.05) and the presence of grade 2 collateral blood flow (p less than 0.01). CONCLUSIONS: When 100 mg of recombinant tissue plasminogen activator was given within the first 6 hours of acute stroke together with heparin the incidence of deleterious hemorrhage was less than 10%. Reperfusion and effective collateral blood flow seem to be two important factors associated with a small infarct volume and good clinical outcome.

Adult

Pure motor hemiparesis with stable somatosensory evoked potential monitoring during aneurysm surgery: case report.

We report a patient who sought treatment for an acute subarachnoid hemorrhage as a result of an intracranial aneurysm. Management included early surgical repair and intraoperative monitoring of evoked potentials. Pan-angiography revealed berry aneurysms of the communicating anterior artery and right middle cerebral artery. Surgery was uneventful, and the somatosensory evoked potential monitoring did not show any abnormalities. Nevertheless, the patient showed a neurological deficit due to a clip-related infarct in the right middle cerebral artery territory characterized by a right hemiparesis with no sensory deficit. This case report supports the possibility of false-negative results in single-mode intraoperative monitoring during aneurysm surgery.

Adult

The spectrum of subcortical lesions in MRI, sensitivity and specificity.

Subcortical foci of increased signal intensity are frequently identified on MRI in the elderly. The lesions are compatible with various pathologic processes and MRI can only provide supportive data for a suspected diagnosis. Without the patient's clinical history the radiologist is not able to differentiate between real pathologic lesions and physiologic aging processes. The high sensitivity of MRI in detecting white matter lesions and the lack of specificity recommends an excellent teamwork between clinicians and radiologists.

Aged

A bivariate version of Andrews plots.

A bivariate version of Andrews plots is introduced for naturally paired multivariate data. The bivariate Andrews plots are space curves, and are particularly effective for revealing patterns and clusters when depicted dynamically. Projections of the bivariate Andrews plots recover the familiar univariate Andrews plots.

Animals

[Experience with flash-evoked visual potentials in unconscious patients in the neurologic intensive care station].

Evoked potential monitoring has become a widely used procedure in the evaluation of stuporous patients on neurological intensive care units. Currently BAEP and SEP are preferentially employed. VEP monitoring is a relatively uncommon procedure, because late evoked potentials tend to be relatively unstable, varying in amplitude to a moderate extend from changes of temperature, drugs, attention and the level of consciousness. A valuable approach of VEP monitoring on intensive care units are structures of the visual system at risk in vascular disease of the vertebrobasilar system or during evaluated intracranial pressure (EIP). This study uses the data of 20 stuporous patients presenting with either intracranial mass lesions or vascular diseases of the vertebrobasilar system and 20 control persons. Light emitting diode (LED)-VEP are compared with checkerboard stimulation in control persons using the technique of cross-correlation. The comparison of the control group with patients using LED-VEP allows definition of limits for normal variation as a base for identification of significant changes. Despite methodical restrictions of LED-VEP, our results are in favour of serial studies in patients with EIP. There are no corresponding findings in LED-VEP and vascular lesions of the retrochiasmatic visual system.

Adult

[Primary non-Hodgkin lymphomas of the central nervous system].

Primary non-Hodgkin's lymphomas (NHL) of the central nervous system are rare brain tumours developing independently of or secondary to disorders of the immune system. In the following review the diagnostic repertoire and various therapeutic modalities are discussed. According to data reported in the literature the therapeutic approach of choice is cranial irradiation with 50 Gy. A positive effect may be expected from additional chemotherapy.

Brain Neoplasms

Multivariate data reduction by principal components, with application to neurological scoring instruments.

Principal components analysis is widely used as a practical tool for the analysis of multivariate data. The aim of this analysis is to reduce the dimensionality of a multivariate data set to the smallest number of meaningful and independent dimensions. The analysis can also provide interpretable linear functions of the original measured variables that may serve as valuable indices of variation. A brief introduction to principal components analysis is given herein, followed by an examination of a particular set of multivariate data accruing from a study of acute brain injuries in a pediatric population, in which severity of brain injury had been assessed with the Glasgow Coma Scale (CGS). Principal components analysis reveals that the GCS sum score is a particularly inefficient summarizer of information in this cohort. The determination of an objective weighting of measured variables, as provided through principal components analysis, is essential in the construction of meaningful neurological scoring instruments.

Coma

Hemorrhagic transformation following tissue plasminogen activator in experimental cerebral infarction.

The effect of an intravenous infusion of recombinant tissue plasminogen activator on hemorrhagic transformation early after middle cerebral artery territory ischemia was studied in an established awake nonhuman primate (baboon) model. Following 3 hours' occlusion of the middle cerebral artery and 30 minutes' reperfusion in each of 30 baboons, a 60-minute infusion of recombinant tissue plasminogen activator (at three doses: Group A, 0.3 mg/kg, n = 6; Group B, 1.5 mg/kg, n = 6; Group C, 10 mg/kg, n = 6) or normal saline (n = 12) was undertaken. The frequency and volume of intracerebral hemorrhage, the volume of infarction, and clinical alterations were determined by computed tomography at 24 hours and 10 days, neuropathology at 14 days, and serial daily neurologic evaluations, respectively. Peripheral (nonintracranial) hemorrhage (Group A, p = 0.46; Group B, p = 0.015; Group C, p = 0.002) and peak plasma tissue plasminogen activator levels varied directly with the dose of recombinant tissue plasminogen activator. Petechial hemorrhagic infarction was a common finding among the 30 baboons. No significant differences in the incidences or volumes of infarction-related hemorrhage were apparent in any group compared with the respective saline-treated baboons. In pooled data, no significant relation between the volume of hemorrhage and the volume of infarction could be established. We conclude that the incidence and severity of hemorrhagic transformation are not related to infarction size and that recombinant tissue plasminogen activator does not increase the incidence or severity (volume) of hemorrhage when given early (less than or equal to 3.5 hours) after the onset of focal cerebral ischemia in this model.

Animals