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At least 1,423 records · Page 79Linked to original sources
PubMed2001

Diffuse brain injury induces local expression of Na+/myo-inositol cotransporter in the rat brain.

We studied expression of an osmoprotective gene, sodium/myo-inositol cotransporter (SMIT) in Marmarou's animal model for human diffuse brain injury by in situ hybridization and immunohistochemistry. In rats with diffuse brain injury, transient upregulation of SMIT mRNA was exclusively observed in the lateral area of pyramidal tract in lower brainstem. The expression was induced at 1 h after injury, peaked at 24 h, and returned to almost control levels at 48 h. Upregulated expression was found mainly in small glia-like cells. By immunohistochemistry using antibodies to phosphorylated mitogen-activated protein (MAP) kinases, inductions of phosphorylated p44/42 MAP kinase were also observed after diffuse brain injury. Interestingly, the distribution patterns of induced phosphorylated p44/42 MAP kinase were completely coincident with those of upregulated SMIT mRNA after diffuse brain injury. These results suggest that diffuse brain injury induces local expression of SMIT by activation of p44/42 MAP kinase cascade. The confined SMIT induction may reflect regional differences of damage and/or cellular differences in sensitivity to neuropathological stresses caused by this injury.

Animals↗
PubMed1987

Cerebrotendinous xanthomatosis (CTX): a clinical survey of the patient population in The Netherlands.

The clinical features and additional investigations of 20 Dutch patients suffering from cerebrotendinous xanthomatosis (CTX), an inborn error of metabolism in bile acid synthesis, are described. The onset was in the second or third decade. The clinical picture at the time of examination consisted of a combination of two or more of the following signs: cataract, xanthoma of a tendon, mental deterioration, pyramidal tract signs, cerebellar signs and epilepsy. Mental retardation was reported in patients. CT-scanning showed cerebellar hypodensity in 8 out of 16 patients but this feature did not correlate well with cerebellar signs. The EEG was abnormal in all but one patient. Treatment with chenodeoxycholic acid resulted in a normalization of EEG and biochemical abnormalities but not of the clinical signs. Cholic acid was equally effective but had much less side effects. The importance of a diagnosis in early life is stressed as well as the examination of clinically unaffected heterozygous relatives.

Adult↗
PubMed2003

A case of adult-onset Alexander disease with Arg416Trp human glial fibrillary acidic protein gene mutation.

Heterozygous point mutations in the coding region of the human glial fibrillary acidic protein (GFAP) gene have been reported in patients with various forms of Alexander disease (AD). We report a case of genetically confirmed adult-onset AD with palatal myoclonus, pyramidal tract signs, cerebellar signs, and marked atrophy of the medulla oblongata and spinal cord, autonomic dysfunction and heterozygous R416W GFAP mutation. Interestingly, this R416W mutation has also been reported in both infantile and juvenile forms of Alexander disease. The fact that a R416W mutation causes various types of AD suggests that clinical severities of AD are due not only to the different sites and nature of mutations in GFAP, but also to other modifying factor(s).

Adult↗
PubMed1999

Cortico-subcortical synchronization in the chloralose-anesthetized cat.

The spontaneous and paroxysmal cerebral cortical synchronized activity was used as reference to study the cortical impact exerted on subcortical neurons. The sensorimotor cortical synchronized activity spread down to subcortical structures receiving direct cortical input, including neuronal populations that originate descending rubrospinal, tectospinal and reticulospinal motor axons, and to a somatosensory relay station, the cuneate nucleus. Lesion of the pyramidal tract abolished the cortically induced synchronization of the activity of contralateral cuneate nucleus neurons.

Anesthesia, Intravenous↗
PubMed1998

Moyamoya disease with concurrent von Recklinghausen's disease and cerebral arteriovenous malformation.

We present a rare autopsy case of von Recklinghausen's disease with Moyamoya vessels and arteriovenous malformation. A 58-year-old female patient suffered from dysarthria and dysphagia. On examination, Parkinson's signs, pseudobulbar palsy, and muscular weakness of the left extremity and pyramidal tract signs were observed. An enhanced brain computed tomography revealed abnormal high-density network vessels at the thalamus and midbrain. By cerebral angiography, the following changes were observed; occlusion of the right internal carotid artery at the bifurcation, and abrupt narrowing and occlusion of the left internal carotid artery at the bifurcation and siphon. A lateral vertebral arteriography revealed telangiectasia at the basilar tip. The patient died of pulmonary thromboembolism at age 61. The vessels of the circle of Willis were hypoplastic. The optic nerves, infundibulum and mammillary body were covered with a large number of ectastic vessels. Arteriovenous malformations were observed in the bilateral occipital lobes. Histopathologically, the elastic lamina of Moyamoya vessel was conspicuously wavy and often duplicated or triplicated, and discontinued occasionally. Discontinuity of the elastic lamina of the perforating arteries and circumferential arteries supplied by the middle cerebral artery (MCA), anterior CA (ACA) and posterior CA (PCA), was also occasionally observed. It is likely that the Moyamoya vessels in this patient were compensatorily formed by congenital hypoplasia of the internal artery, MCA, ACA and PCA.

Fatal Outcome↗
PubMed1981

[Transcortical reflexes of proprioceptive origin and motor epilepsy (author's transl)].

The long-loop reflex involved in the triggering of paroxysmal activities by proprioceptive afferents is examined in monkeys with a chronic alumina focus and in cats with an acute penicillin focus. Electrical stimulation of a tibial nerve in monkeys as well as muscle stretch in cats elicit a cortical 'evoked spike', i.e., an evoked potential followed by an epileptic spike, accompanied by one or two motor bursts in the muscles concerned. With a very small acute focus, this transcortical reflex is shown to be quite topical: muscles in the vicinity are not affected. Relationships between evoked spike and myoclonic jerk are examined and it is shown that motor efferents usually follow the pyramidal tract. The concept of a transcortical reflex of proprioceptive origin is discussed on the basis of data collected from these models.

Afferent Pathways↗
PubMed2000

An autopsy case of atypical adrenoleukomyeloneuropathy in childhood.

Adrenoleukomyeloneuropathy (ALMN) usually occurs in adulthood, it being extremely rare in childhood. We reported a quite atypical clinical case of ALMN as a variant of adrenoleukodystrophy (ALD). The onset was at 5 years 7 months and ataxia was the major symptom. His condition progressed rapidly to a vegetative state within 1 year. At the age of 11 years and 11 months he died of pneumonia and an autopsy was performed. We herein reported the neuropathological findings in this rare case. The autopsy revealed marked atrophy with diffuse demyelination and astrogliosis throughout the cerebrum, cerebellum and brainstem. Massive degeneration of the pyramidal tracts and loss of neurons were also seen in the spinal cord. The adrenal cortex showed marked atrophy with a striated cytoplasm in ballooned cells. These findings include pathological characteristics of both ALD and adrenomyeloneuropathy (AMN), suggesting ALMN. However, diffuse demyelination with gliosis in the cerebrum and cerebellum is quite atypical for ALMN. They might explain his atypical clinical course, especially the early onset of the disease with ataxia and rapid deterioration.

Adrenoleukodystrophy↗
PubMed2001

A Japanese girl with leukoencephalopathy with vanishing white matter.

A Japanese girl with peculiar leukoencephalopathy was reported. Following normal development until 1 year of age, she showed progressive neurological deterioration with ataxia, epilepsy, pyramidal tract signs and choreic movement. Serial brain computed tomographies (CTs) revealed markedly low density and progressive volume loss in whole white matter. In extensive laboratory investigations, the level of glycine in the urine was elevated. She died at the age of 4 years, and the neuropathological findings were comprised of severe extensive changes in cerebral and cerebellar white matter, such as marked rarefaction or cystic degeneration with axonal loss. The pontine central tegmental tracts were also affected. Neuronal loss was seen in the cerebellar cortex. These features were compatible with leukoencephalopathy with vanishing white matter, which was recently established as a clinical entity. To our knowledge, this is the first report of a non-Caucasian patient with this new type of leukoencephalopathy.

Brain↗
PubMed1990

A possible Japanese male case of Pelizaeus-Merzbacher disease.

A boy with an abnormal auditory brain stem response showing only a wave I-II pattern, congenital nystagmus, psycho-motor retardation, pyramidal tract signs and muscular hypotonia was reported. The auditory brain stem response, short latency somatosensory-evoked potential, somatosensory-evoked potential and visual-evoked potential indicated an intramedullary disorder of conduction. Magnetic resonance imaging revealed marked high signal intensity of the cerebral white matter in T2-weighted images, suggesting hypomyelination. A muscle biopsy specimen showed neurogenic changes with mild myogenic changes.

Brain↗
PubMed1984

Fukuyama type congenital muscular dystrophy--two Dutch siblings.

Two Dutch siblings, diagnosed as suffering from Fukuyama type congenital muscular dystrophy (FCMD) on the basis of clinical, computerized tomography (CT), and muscle and brain biopsy findings, are reported. Hypoplasia of the chorioidea was observed for the first time in FCMD. Autopsy of the first case revealed the major pathological changes of FCMD, i.e. micropolygyria, loss of cytoarchitecture, hypoplasia of the pyramidal tract, leptomeningeal thickening. Heterotopias of nervous tissue in the spinal arachnoidal spaces were found. This is the first case in which brain tissue has been investigated on two separate occasions. In the biopsy specimen--at the age of 14 months--myelination was poor and astrogliosis marked. At autopsy--4 years later--myelination proved to be only slightly less than normal. However, white matter hypodensities on the successive CT's did not change. There is no ready explanation for this discrepancy. Typical FCMD is compared to FCMD-like cases from outside Japan. There are arguments in favor of the concept of a continuum of diseases--with the same (unknown) etiology--representing both typical FCMD and other types of congenital muscular dystrophy with CNS lesions.

Brain↗
PubMed1989

Giant axonal neuropathy. A review.

First reported in 1972 by Berg & colleagues, giant axonal neuropathy is a generalized disorder of cytoplasmic intermediate filaments affecting the nervous system particularly. The condition was originally thought to be a disorder of the peripheral nervous system, but clinical and pathological evidence has now accumulated which indicates that the brain and spinal cord are progressively involved. Over 20 cases have been reported to date. All cases reported have developed clumsiness and progressive weakness with hyporeflexia in the first seven years of life. Later dysarthria, cerebellar signs and pyramidal tract disturbances appear. Mental retardation, dementia and seizures are sometimes seen. Tightly curled hair is characteristic of, but not invariably present in, the condition. This disorder, as well as a similar condition affecting dogs, appears to be transmitted by autosomal recessive inheritance. No treatment is effective. Most cases are wheelchair bound or dead by the end of the second decade.

Axons↗
PubMed1997

Pial-glial barrier abnormalities in fetuses with Fukuyama congenital muscular dystrophy.

This report concerns light and electron microscopic studies on the central nervous system of a 20-week and an 18-week fetus with Fukuyama congenital muscular dystrophy (FCMD). The diagnosis of FCMD was established by prenatal molecular genetic analysis. Cerebral lesions containing neurites, subpial granular cells and glias, accompanied by cortical dysplasia were found in both cases. Small irregular defects, readily detectable by periodic acid-methenamine-silver staining or by immunohistochemical staining for S-100 protein, were observed in the cerebral surface. More severe dysplasia was evident at the areas with the larger defects. Surface defects were also observed in the cerebellum and brain stem, with brain tissue extruding into the leptomeninges. The pyramidal tract was aberrant in the pons and medulla oblongata. The spinal cord appeared normal by light microscopy. Electron microscopic examination revealed an abnormal configuration of the basement membrane and glial cytoplasmic membrane of the brain and spinal cord surfaces, including areas with no detectable defects by light microscopy. These findings suggest that abnormalities of the pial-glial barrier, especially the basement membrane and/or basement membrane-related structures, are involved in the genesis of cortical dysplasia.

Blood-Brain Barrier↗
PubMed2001

Palliative care in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is the most common degenerative motor neuron disease in adults. The clinical picture consists of generalized fasciculations, progressive atrophy and weakness of the skeletal muscles, spasticity and pyramidal tract signs, dysarthria, dysphagia, and dyspnea. Pseudobulbar affect is common. Disease-specific treatment options are still unsatisfactory. Therapeutic nihilism is not justified as a large array of palliative measures available to enhance the quality of life of patients and their families. Because of its clinical characteristics, ALS represents a paradigm for palliative care in neurological diseases. Numerous projects are being undertaken worldwide in an effort to enlarge the evidence base for palliative interventions in ALS. Palliative care in ALS is a multidisciplinary effort requiring careful coordination. An open and empathic disclosure of the diagnosis is essential. Nutritional deficiency caused by dysphagia can be relieved by a percutaneous endoscopic gastrostomy. Respiratory insufficiency can be effectively treated by non-invasive home mechanical ventilation. The terminal phase of the disease should be discussed at the latest when symptoms of dyspnea appear, in order to prevent unwarranted fears of "choking to death." Psychological and spiritual care of patients and families are important. Collaboration with hospice institutions and completion of advance directives can be of invaluable help in the terminal phase.

Amyotrophic Lateral Sclerosis↗
PubMed2002

Focal clonus elicited by electrical stimulation of the motor cortex in humans.

Focal clonic seizures are a frequent epileptic phenomenon. However, there are little data about their pathomechanism. In four patients with focal epilepsy and subdural electrodes, focal clonus was elicited by electrical stimulation of the motor cortex. Three additional patients underwent intraoperative stimulation of the spinal cord. Rhythmic clonic muscle responses were elicited by cortical stimulation with 20-50 Hz. The clonus consisted of simultaneous trains of compound muscle action potentials (CMAP) in agonistic and antagonistic muscles alternating with periods of muscular silence despite continuous stimulation. Clonus frequency decreased from 4.0-8.0 Hz at 50 Hz stimulation to 3.0-3.5 Hz at 20 Hz paralleled by a prolongation of the trains of CMAP. The stimulation frequency correlated with the number of stimuli blocked during relaxation. During the stable stimulation periods, the clonus frequency decreased over time. The number of stimuli which formed a train of CMAP and which were blocked during relaxation increased towards the end of the stimulation periods. Increasing intensity of stimulation at the same frequency converted a clonic to a tonic response. There was always an 1:1 relationship between stimulus and CMAP during spinal cord stimulation. We hypothesize that during cortical stimulation, clonus is elicited by synchronous activation of pyramidal tract (PT) neurons which results in excitation of intracortical GABA(B)ergic interneurons by recurrent axon-collaterals. This leads to stepwise hyperpolarization of PT neurons intermittently suppressing the output of PT neurons despite continuous stimulation. This mechanism can explain our finding that temporal and spatial summation of the stimuli were needed for clonus generation.

Action Potentials↗
PubMed2000

Seizures induced by penicillin microinjections in the mesencephalic tegmentum.

The location and extension of a convulsive area in the brain stem in cats was determined through penicillin microinjections (0.5-1.0 microl) of a concentrated sodium penicillin solution (500 IU/microl), stereotactically oriented to multiple structures, in fully awake animals, partially restrained through a rod fixation system that avoided pain, allowed the observation of clinical seizures and simultaneous recording of EEG, EMG and multiple unit activity (MUA) from the injected site and the motor cortex (Cx). Clinical and EEG seizure patterns in relation to the injected sites and penicillin doses were studied in another group of animals using doses from 12.5 IU/0.1 microl to 125 IU/1.0 microl. The time relationship between muscular clonus, EEG spikes and MUA at the injected site and Cx were analyzed. The only area in which penicillin induced seizures was the mesencephalic tegmentum (MT). The amount of penicillin but not the stereotactic coordinates determined the seizure type. MT EEG and MUA paroxysms anticipated clinical seizure and Cx EEG spikes. When Cx EEG appeared, they were accompanied by an increase in MUA beginning in the Cx and EMG, followed by significant increase in MT MUA. The sequence of events suggest that MT seizure activity propagates via alternative pathways not involving direct reticulospinal or pyramidal tract pathways.

Animals↗
PubMed1995

Congenital errors of folate metabolism.

Congenital errors of folate metabolism can be related either to defective transport of folate through various cells or to defective intracellular utilization of folate due to some enzyme deficiencies. Defective transport of folate across the intestine and the blood-brain barrier was reported in the condition 'Congenital Malabsorption of Folate'. This disease is characterized by a severe megaloblastic anaemia of early appearance associated with mental retardation. Anaemia is folate-responsive, but neurological symptoms are only poorly improved because of the inability to maintain adequate levels of folate in the CSF. A familial defect of cellular uptake was described in a family with a high frequency of aplastic anaemia or leukaemia. An isolated defect in folate transport into CSF was identified in a patient suffering from a cerebellar syndrome and pyramidal tract dysfunction. Among enzyme deficiencies, some are well documented, others still putative. Methylenetetrahydrofolate reductase deficiency is the most common. The main clinical findings are neurological signs (mental retardation, seizures, rarely schizophrenic syndromes) or vascular disease, without any haematological abnormality. Low levels of folate in serum, red blood cells and CSF associated with homocystinuria are constant. Methionine synthase deficiency is characterized by a megaloblastic anaemia occurring early in life that is more or less folate-responsive and associated with mental retardation. Glutamate formiminotransferase-cyclodeaminase deficiency is responsible for massive excretion of formiminoglutamic acid but megaloblastic anaemia is not constant. The clinical findings are a more or less severe mental or physical retardation. Dihydrofolate reductase deficiency was reported in three children presenting with a megaloblastic anaemia a few days or weeks after birth, which responded to folinic acid. The possible relationship between congenital disorders such as neural tube defects or dihydropteridine reductase deficiency and disturbances of folate metabolism are discussed. Neurological symptoms present in most of these congenital disorders highlight the role of folate in the central nervous system.

Female↗
PubMed1996

[Alterations of various parameters of evoked motor potentials in amyotrophic lateral sclerosis].

To assess their interest, we studied different motor evoked potentials (MEP) parameters in 18 amyotrophic lateral sclerosis (ALS) patients and compared them to those obtained in 20 subjects unaffected by neurological diseases: cortical threshold (CT), latency and amplitude of primary responses (PR), central conduction time (CCT), silent period (SP) contralateral to the stimulated cortex and late muscular responses (LMR). In normal subjects MEP parameters were in agreement with those described in the literature, except for LMR. These were only recorded in upper limbs with latencies around 200 ms in 9 out of 20 subjects. In ALS patients, LMR were not modified as compared to normal subjects. Except for mean CCT, in upper and lower limbs, all parameters were altered. We conclude that all MEP parameters are useful in ALS and disclose the involvement of the entire pyramidal tract in this disease.

Amyotrophic Lateral Sclerosis↗
PubMed2006

[Study of 3 white matter fiber trackings using MRI diffusion].

UNLABELLED: The aim of this study is to evaluate the interest of diffusion weighted MRI for the study of white matter fiber tracking. METHODS: Fifteen subjects having undergone diffusion weighted MRI have been included. Three white matter fiber trackings have been studied for each subject: interhemispheric transcallosum, optic radiations and pyramidal tracts. The results were compared to an atlas of human anatomy. RESULTS: All the white matter tracts studied have been visualized. The morphology of the three white matter tracts was similar to standard anatomy. The orientation of the three white matter tracts was determined in 100% of the cases. CONCLUSION: diffusion weighted MRI allowed the morphological study of all the analyzed white matter tracts. This technique might, therefore, help to evaluate nerve fiber tracts and guide neurosurgical interventions.

Brain↗