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At least 613 records · Page 34Linked to original sources
PubMed2003

[Intrathecal glutamate receptor antibodies in a patient with elderly-onset refractory epilepsy].

Antibodies against a glutamate receptor in the central nervous system are reported to be an important autoimmune factor in infantile or childhood refractory epilepsy and in adult-onset paraneoplasstic cerebellar ataxia. We here reported a patient with glutamate receptor antibodies-positive elderly-onset intractable epilepsy and advanced-stage stomach cancer. A 77-year-old man with a history of resected bladder cancer suddenly developed an attack of epilepsia partialis continua in the right arm, followed by a generalized epileptic status. The ictal EEG showed spikes in the left parietal region with diffuse slow wave backgrounds. The brain MRI demonstrated a focal high signal intensity in the left postcentral gyrus on the T2-weighted and FLAIR images. The SPECT showed a high uptake in the focal area corresponding to the MRI lesion, suggesting a seizure focus. The routine analysis in the CSF was normal, but the glutamate receptor antibodies (IgG, IgM and C-terminal) were all positive. The status epilepticus was refractory to anticonvalsants, and the barbiturate anesthesia was introduced. Subsequently, the epilepsy has been fairly controlled by valproic acid and phenobarbital. The post ictal MRI demonstrated a focal atrophy in the left postcentral gyrus. The systemic evaluations revealed an advanced-stage stomach cancer. The glutamate receptor antibodies may play a role in late-onset refractory epilepsy, and may be an autoimmune factor in paraneoplstic neurologic syndrome presenting with epilepsy.

Aged↗
PubMedDate not supplied

[Delayed-type subacute measles encephalitis].

INTRODUCTION: We analyze the clinical, neurological, EEG, neuroradiological features and evolution of two patients with subacute measles encephalitis. CASE REPORTS: The patients, aged five years and eleven months respectively showed an acute, progressive neurological compromise and deterioration of consciousness, epilepsia partialis continua and progressive damage on neuroimaging, with a history of measles in the first case and exposure to the virus in the second. The first patient had Hodgkin's disease and the other had a familial C4 deficit disorder. Fundoscopic examination showed lesions on the retina. The EEG showed unilateral slow waves and spikes. Brain CT and MRI revealed progressive cerebral atrophy and a unilateral corticosubcortical lesion. Measles antibodies in CSF were found in the first child and oligoclonal bands in the second. Our first patient died after three months and the second has a severe neurological damage. CONCLUSION: In immunocompromised patients with the exposure to a history of measles, acute neurological compromised and deterioration of consciousness, epilepsia partialis continua and progressive damage on neuroimaging, subacute measles encephalitis should be considered.

Acute Disease↗
PubMed1988

Electrocochleography: methods and clinical applications.

The use of electrocochleography (ECoG) as a tool in the diagnosis, assessment, and monitoring of certain neuro-otologic disorders has attracted renewed attention in the United States. The use of ECoG among otologists and audiologists has increased in recent years, primarily due to the availability of relatively easily applied, noninvasive extratympanic electrodes. Information derived from ECoG recordings has been shown to be helpful in the objective identification and monitoring of Meniere's disease and endolymphatic hydrops. In addition, ECoG may be used to enhance our ability to observe the most peripheral component of the auditory brain stem response (Wave I) for routine clinical assessment or during intraoperative monitoring procedures in which certain structures of the ear are at risk for permanent damage. This article provides an overview of current techniques and clinical applications of ECoG.

Audiometry, Evoked Response↗
PubMed1988

Assessment of neurologic damage: creatine kinase-BB assay after cardiac arrest.

The assay of cerebrospinal fluid creatine kinase-BB (CK-BB) after cardiac arrest has demonstrated a relationship between CK-BB activity and neurologic recovery; a high concentration of cerebrospinal fluid CK-BB can be associated with lower Glasgow Coma Scale scores, intracranial pressure plateau waves, and histologic brain damage on death. Analysis of cerebrospinal fluid CK-BB is most reliable when it is done within 48 to 72 hours of the arrest. The appearance of serum CK-BB after a cardiac arrest indicates global ischemia, but has not been shown to be a reliable indicator for outcome, because of its rapid inactivation in the body. However, investigations into methods of reactivation of CK-BB show promise in terms of future use of this assay technique.

Brain Damage, Chronic↗
PubMed1994

Mammalian cardiovascular morphology and the maintenance of cerebral function at high Gz.

The persistence of consciousness at low cerebral perfusion pressures during exposure to high sustained G force in a head-to-foot direction (+Gz), is the rule. Concomitant changes in cerebrospinal fluid and cerebral venous dynamics together with cerebral autoregulation have been proposed to explain this preservation of cerebral function at high Gz. The non-uniform distensibility of the mammalian aortic distributing system plays a fundamental role in maintaining optimal cardiac energy exchange. Morphological evidence is presented suggesting that such a non-uniformity probably extends cranially as well as caudally in man. One consequence of such a cranial extension would be the amplification of the arterial pressure waves to the brain, with the potential for significant pulsatile flow at relatively low mean arterial blood pressures. Such phenomena would result from fundamental design properties of the mammalian cardiovascular system, would not be detected by conventional invasive pressure monitoring, and would serve as a mechanism to maintain optimal cerebral perfusion under condition of increasing +Gz.

Animals↗
PubMed1993

Temperature drop and sleep: testing the contribution of SWS in keeping cool.

Sleep and body temperature characteristics were studied in man in baseline (B), 24 h-constant routine (CR) and recovery (R) after the CR. The sleep advanced and deepened the trough of the minimum temperature when compared with CR. No relevant difference in minimum body temperature, or in the slope of temperature decrease was found, however, between B and R sleeping nights. No correlation was found between the amount of slow wave sleep and body cooling. The results do not support a homeostatic role of slow wave sleep in brain and/or body cooling.

Adult↗
PubMedDate not supplied

[The use of millimeter waves in neurosurgery under electrophysiological control].

Patients with organic CNS lesions including epileptic syndrome can be treated using indirect influence of millimetric waves upon major brain regulatory systems via specific peripheral receptor fields under control of adequate bioelectric criteria. 42 brain-affected patients were studied. The above method used as a part of combined surgical treatment resulted in stable functional restoration and normalization of bioelectric brain activity.

Adolescent↗
PubMed2000

Scar/WAVE-1, a Wiskott-Aldrich syndrome protein, assembles an actin-associated multi-kinase scaffold.

WAVE proteins are members of the Wiskott-Aldrich syndrome protein (WASP) family of scaffolding proteins that coordinate actin reorganization by coupling Rho-related small molecular weight GTPases to the mobilization of the Arp2/3 complex. We identified WAVE-1 in a screen for rat brain A kinase-anchoring proteins (AKAPs), which bind to the SH3 domain of the Abelson tyrosine kinase (Abl). Recombinant WAVE-1 interacts with cAMP-dependent protein kinase (PKA) and Abl kinases when expressed in HEK-293 cells, and both enzymes co-purify with endogenous WAVE from brain extracts. Mapping studies have defined binding sites for each kinase. Competition experiments suggest that the PKA-WAVE-1 interaction may be regulated by actin as the kinase binds to a site overlapping a verprolin homology region, which has been shown to interact with actin. Immunocytochemical analyses in Swiss 3T3 fibroblasts suggest that the WAVE-1 kinase scaffold is assembled dynamically as WAVE, PKA and Abl translocate to sites of actin reorganization in response to platelet-derived growth factor treatment. Thus, we propose a previously unrecognized function for WAVE-1 as an actin-associated scaffolding protein that recruits PKA and Abl.

3T3 Cells↗
PubMed1986

Development of auditory-evoked potentials in the cat. III. Wave amplitudes.

Amplitudes of auditory-evoked brain stem response (ABR) and late-occurring auditory-evoked potential (AER) components were recorded from kittens between birth and 90 postnatal days. All ABR and AER wave amplitudes increased during the first postnatal month. Wave amplitudes exhibited nonmonotonic growth with increasing age, attaining a maximum at 40-60 days of age, after which amplitudes decreased. Amplitudes of waves originating in the auditory nerve matured somewhat faster than waves originating in the brain stem and forebrain, and the order in which waves reached maturity was roughly the reverse order of the latencies of their peaks. Input-output curves for ABR and AER waves displayed nonmonotonic behavior that varied as a function of postnatal age. Wave amplitudes recorded from adult cats increased between threshold and 70 dB SPL, then decreased between 70 and 100 dB SPL, and rapidly increased above 100 dB SPL. The intensity corresponding to the change from increasing to decreasing amplitudes was higher for younger animals and achieved adult values during the first postnatal month.

Aging↗
PubMedDate not supplied

Longitudinal EEG findings in dementia related to the parietal brain syndrome and the degree of dementia.

EEG slow-wave activity was correlated with the regional brain syndrome profile in 74 patients with dementia. The EEGs were visually assessed using a semiquantitative rating scale. The intensities of four regional brain syndromes (parietal, frontal, subcortical, global) and the degree of dementia were rated. The patients were examined twice with a 1-year interval. A significant relationship was found between the increase in EEG slow-wave activity and the increase in intensity of the parietal brain syndrome. A somewhat lower significance was found for the relation between increase in slow-wave activity and increase in dementia degree. The results suggest that the EEG deterioration in dementia mainly reflects the gradual decline of parietal brain function.

Aged↗
PubMed1976

Acute spontaneous volume fluctuation in the brain. A contribution to the interpretation of plateau waves. Results of CSF measurements with ventricular drainage.

Primarily the theoretical background of the relation between the intracranial pressure and the volume is discussed. From the definite relationship between volume and pressure it is deduced that with the appropriate equipment intracranial volume changes may be measured instead of the I.C.P. The exact measurement of the volume of CSF drained in relation to the drainage time enable us to differentiate disturbances of the C.S.F. circulation in patients. Furthermore we were able to correlate "plateau waves" with certain amounts of volume fluctuations; these were shown in amounts of drained C.S.F. between 16 and 32 ml. Some scientific aspects of this new method and possible results are pointed out.

Blood Volume↗
PubMed2003

Depolarization waves in the embryonic CNS triggered by multiple sensory inputs and spontaneous activity: optical imaging with a voltage-sensitive dye.

Previously, we discovered a novel type of depolarization wave in the embryonic chick brain by using a multiple-site optical recording technique with a fast voltage-sensitive dye. This depolarization wave traveled widely over almost all the region of the CNS. This profile has raised the possibility that the depolarization wave plays some global roles in development of the CNS, rather than contributing to a specific neuronal circuit formation. To obtain more information concerning this issue, in the present study, we examined whether the depolarization wave was triggered by various types of peripheral nerve inputs. Stimulation applied to the vagus, glossopharyngeal, cochlear and trigeminal nerves evoked widely spreading depolarization waves with similar spatiotemporal distribution patterns. The developmental sequence of wave expression was parallel to the development of the excitatory postsynaptic potentials in each sensory nucleus. The depolarization wave was accompanied by a Ca(2+)-wave, suggesting that not only electrical synchrony, but also large-scale Ca(2+)-transients may affect developmental processes in the embryonic brain. Furthermore, we found that the depolarization wave also occurred spontaneously. The waveform and distribution patterns of the spontaneous optical signals were similar to those of the cranial nerve-evoked depolarization wave. These results demonstrated that the depolarization wave in the embryonic chick brain is triggered by multiple sources of external and endogenous activity. This profile supports the idea that this depolarization wave may not serve as a simple regulator of specific neuronal circuit formation, but might play more global roles in CNS development.

Animals↗
PubMed1978

Significance of the ventricular fluid pressure wave form in the diagnosis of cerebral circulatory arrest and brain death.

The fluctuations in the absolute value of the ventricular fluid pressure (VFP) with simultaneous changes in the amplitude and frequency of the oscillations of the ventricular fluid wave form are described in seven patients who developed brain death following either a head injury or a cerebrovascular accident, and are compared with those observed in nineteen patients who survived similar brain pathology. The findings in the two groups were significantly different. It is suggested that VFP monitoring does provide reliable evidence of brain death even while the patient is on artificial respiration.

Adolescent↗
PubMed1989

Evaluation of a computer-automated program for clinical assessment of the auditory brain stem response.

An evaluation of an automatic auditory brain stem evaluation (AABE) for waves I, III, and V, of the auditory brain stem response (ABR) is presented. The on-line procedure performs a mathematical analysis of ABR waveforms using principles similar to those used by experienced clinicians to make threshold and latency decisions. It has been tested and applied to normal and pathologic traces at stimulus levels from 20 to 100 dB HL. Subject ages ranged from 6 months through adulthood. Latencies and thresholds determined by the analytic technique were examined and found to be indistinguishable from decisions of two "expert" observers and four practicing clinical audiologists experienced in ABR. Speed, practicality, and limitations of the software for routine ABR assessments are discussed.

Adolescent↗
PubMed1997

Brain stem auditory-evoked response in relation to neonatal glucose metabolism.

Imprecise control of glucose homeostasis is a hallmark of neonatal glucose metabolism. A relatively wide range of glucose concentrations is considered 'euglycemic' (2.22-6.94 mmol/l, 40-125 mg/dl) in the neonatal period. We investigated the effects of a wide range of glucose concentrations on brain stem conduction time (BCT) I-V interpeak latency or prolonged wave V latency. Neonates were assessed by brain stem auditory-evoked response followed immediately by heelstick sampling to determine the blood glucose concentration. Twenty-seven appropriate for gestational age (AGA) term neonates (birth weight 3,245 +/- 766 g, mean +/- SD; gestational age 39 +/- 2 weeks) were studied 3.1 +/- 3.7 days after birth. Twenty-three AGA preterm neonates (birth weight 2,175 +/- 477 g; gestational age 35 +/- 1 weeks) were studied 6.0 +/- 7.2 days after birth. Brain stem conduction time wave I-V interpeak latency and wave V latency were determined in two trials using a Grason-Stadler ABR screener at a 60-decibel stimulation level in the right ear. Neonates were studied between 33 and 40 weeks gestational age. Although the blood glucose concentration ranged from 1.38 to 6.83 mmol/1 (25-123 mg/dl), there was no correlation between either brain stem conduction time wave I-V interpeak latency or wave V latency and blood glucose concentration. We conclude that alterations in glucose concentration within the generally accepted neonatal euglycemic range do not effect the functional status of the brain stem auditory pathway. We suggest that the data can be interpreted to affirm that tighter clinical control of glucose homeostasis is probably not required in the neonatal period.

Birth Weight↗
PubMed1995

Utility of cerebral proton magnetic resonance spectroscopy in differential diagnosis of HIV-related dementia.

Opportunistic infections often coexist with human immunodeficiency virus (HIV) infection in brain. Making the correct diagnosis is often difficult despite recent advances in neuroimaging techniques. 1H magnetic resonance spectroscopy (1H MRS) is an emerging non-invasive examination for diagnosis and monitoring of brain disorders. 1H MRS measures a variety of organic compounds using magnetism and radio waves. Biochemical aberrations in brain, not shown by conventional tests, may be demonstrated by 1H MRS testing. A patient coinfected with HIV and hepatitis B (HBV) presented with progressive dementia. Clinical, neuroradiological and cerebrospinal fluid (CSF) examinations failed to provide a diagnosis in support of either HIV-1-associated cognitive/motor complex or HBV-induced hepatic encephalopathy (HE), 1H MRS was used in an attempt to discriminate between these diagnoses. Spectroscopy demonstrated increased glutamine and normal N-acetyl aspartate (NAA) levels, metabolic changes consistent with HE. These findings were later confirmed pathologically. Proton magnetic resonance spectroscopy is a non-invasive test with utility for the differential diagnosis of HIV-associated dementia.

AIDS Dementia Complex↗
PubMed1981

[Local brain consumption of glucose during waking and slow wave sleep in the cat].

Local cerebral glucose utilization (LCGU) was measured during spontaneous waking and slow wave sleep (SWS) by adaptation of the [14C] deoxyglucose method to the unrestrained Cat. During waking LCGU ranges from 12 micromoles. 100g-1.mn-1 for white matter to 113 for the inferior colliculus. During SWS most regions exhibit higher levels of LCGU. Thus it appears that there is no decrease of cerebral metabolic activity during SWS in the Cat.

Animals↗