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Results for “Pyramidal Tracts”

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PubMed1999

Choreic movements and MRI abnormalities in the subthalamic nuclei reversible after administration of coenzyme Q10 and multiple vitamins in a patient with bilateral optic neuropathy.

A 37-year-old man developed choreic movements of the limbs over a few months. His medical history included bilateral visual loss detected at the age of 9 and worsening at age 20. Visual field testing showed a central scotoma. Fundus examination showed atrophy of the optic disks and narrowing of vessels. The diagnosis of Leber hereditary optic neuropathy (LHON) was considered. There was no family history of visual loss or movement disorders. Blood lactate:pyruvate ratio was moderately elevated. Skeletal muscle biopsy was normal. Magnetic resonance imaging showed bilateral hypointense lesions on T1-weighted sequences in the subthalamic nuclei and in the lateral part of the substantia nigra. Linear hyperlucencies in the pyramidal tract facing the lateral part of the ruber nuclei were also demonstrated on T2-weighted sequences. Nine LHON-associated mutations were ruled out by RFLP analysis. Treatment with 250 mg coenzyme Q10 per day and multiple vitamins was initiated. Gradual recovery in movement disorders occurred over 1 year. Lactate to pyruvate ratio normalized. No change of visual function was observed. On magnetic resonance imaging performed 3 years later, lesions of the subthalamic nuclei almost completely disappeared. We think the patient might have an unusual, genetically uncharacterized mitochondrial disorder, combining optic neuropathy and chorea.

Adult↗

PubMed1987

Nerve cell death in degenerative diseases of the central nervous system: clinical aspects.

The origin of degenerative diseases of the central nervous system lies in genetic and acquired disorders. Analysis of the clinical characteristics of diseases affecting specific neuronal systems may help us to understand their pathogenesis. The stereotyped symptomatology characteristic of most degenerative diseases results from neuronal death in specific pathways: pyramidal tract and motor neurons in amyotrophic lateral sclerosis, nigrostriatal dopamine system in Parkinson's disease, posterior and lateral columns of the spinal cord in Friedreich's ataxia, etc. This suggests that these neurons are sensitive to pathological processes that are still unknown. Progression of the disease, whether linear or not, is slow, but it is more rapid than similar effects due to ageing. This indicates either that the environmental cause of degeneration (if it exists) is continuously present or that a vital process has been once and for all disrupted, perhaps at the level of the genome, causing insufficient production of essential proteins, or accumulation of eventually toxic metabolites. Symptoms generally appear during adulthood, i.e. after normal differentiation has taken place, and after a considerable number of neurons have already been damaged. The initiation of neuronal death precedes the appearance of the first symptoms.

Adult↗

PubMed1987

Remodelling of early axonal projections through the selective elimination of neurons and long axon collaterals.

Studies using neuroanatomical techniques have shown that the connections characteristic of the mature vertebrate brain are brought about by a considerable refinement of the projections initially established during development. The selective loss of neurons and long axon collaterals plays a major role in this remodeling process as illustrated in the development of the retina and cortex of the rat. In the retina, two-thirds of the initial population of ganglion cells (RGCs) die early. This loss serves to remove selectively RGCs that make erroneous axonal projections, including those which project to an incorrect target, to an inappropriate part of a correct target, or to the wrong side of the brain. Studies using the sodium channel blocker, tetrodotoxin, suggest that in rats the selective elimination of erroneously projecting RGCs is based, in part, on patterns of impulse activity. In the cortex a different mechanism is illustrated. All neocortical areas initially give rise to callosal and pyramidal tract axons but through a process of selective collateral elimination not involving cell death these projections assume the limited distributions seen in adult rats. Manipulations resulting in the maintenance of such long collaterals suggest that their removal is functionally and locally determined. In contrast to error elimination, this phenomenon of collateral elimination may be a developmental strategy for generating connectional diversity while limiting the amount of information required for the regional specification of the cortex.

Animals↗

PubMed1982

Carbon disulfide-induced neuropsychiatric changes in grain storage workers.

The clinical and neuropsychiatric features of seven workers from the grain storage industry are described. All were exposed to fumigants, especially carbon disulfide and malathion. Clinical manifestations included cogwheel rigidity, resting and action tremor, peripheral neuropathy, pyramidal tract signs, an EEG pattern of sleep apnea, and characteristic measurable neurobehavioral dysfunction. Similar signs and symptoms due to carbon disulfide exposure in the viscose rayon industry strongly supported the conclusion that these grain storage workers were suffering from carbon disulfide poisoning. Malathion exposure probably had a contributing role. We conclude that exposure to these fumigants poses a serious occupational risk to the nervous system.

Aged↗

PubMed2002

Autosomal dominant sensory/motor neuropathy with Ataxia (SMNA): Linkage to chromosome 7q22-q32.

The autosomal dominant (AD) spinocerebellar ataxias (SCAs) and hereditary sensory neuropathies (HSN) are heterogeneous disorders characterized by variable clinical, electrophysiological, and neuropathological profiles. The SCAs are clinically characterized by slowly progressive incoordination of gait often associated with poor coordination of hands, speech, and eyes. Peripheral neuropathy is not a frequent part of the SCA syndrome. In contrast, the HSNs are primarily characterized by progressive sensory loss. There is substantial clinical overlap between the various SCAs and the various HSNs, and they often cannot be differentiated on the basis of clinical or neuro-imaging studies. We have identified a five-generation American family of Irish ancestry with a unique neurological disorder displaying an AD pattern of inheritance. There was variable expressivity and severity of symptoms including sensory loss, ataxia, pyramidal tract signs, and muscle weakness. Nerve conduction studies were consistent with a sensory axonal neuropathy. Muscle biopsy revealed neurogenic atrophy and brain MRI showed mild cerebellar atrophy. To identify the responsible locus we pursued a whole genome linkage analysis. After analyzing 114 markers, linkage to D7S486 was detected with a two point LOD score of 4.79 at theta = 0.00. Evaluation of additional markers in the region provided a maximum LOD score of 6.36 at theta = 0.00 for marker D7S2554. Haplotype analysis delimited an approximately 14-cM region at 7q22-q32 between markers D7S2418 and D7S1804 cosegregating with the disease. Because this disorder does not easily fall into either the SCA or HSN categories, it is designated sensory/motor neuropathy with ataxia (SMNA).

Adolescent↗

PubMed1986

Shift to righthandedness in Rett syndrome around age 7.

This paper confirms Nomura's finding (Nomura et al, 1984) that almost all of those children with Rett syndrome under 7 who grasp objects are lefthanded. It is suggested that the lefthandedness in Rett syndrome up to age 7 comes from a functional lateralization of the cerebral hemispheres similar to that which Birkmayer and Rett proposed for normal infants up to age 1 (Birkmayer and Rett, 1954). However, examination of children over 7 showed that almost all of those patients who grasp objects prefer the right hand and show symptoms of disturbance of the functions of the pyramidal tract that are more pronounced in the left than in the right upper limb. It is suggested that in connection with the severe developmental retardation of the CNS in Rett syndrome the right shift factor of handedness (Annett, 1981) has a belated manifestation. Within the framework of a regression of the CNS there occurs a regression which is more pronounced in the right cerebral hemisphere than in the left.

Adolescent↗

PubMed1990

The central nervous system in the Apert syndrome.

In this paper, we present available central nervous system data from our series of patients with the Apert syndrome. Combining our own data with that available in the literature, 30 patients had malformations of the corpus callosum, the limbic structures, or both. Other frequent findings included megalencephaly (7 cases), gyral abnormalities (8 cases), encephalocele (4 cases), pyramidal tract abnormalities (2 cases), hypoplasia of cerebral white matter (4 cases), and heterotopic gray matter (2 cases). Progressive hydrocephalus seems to be uncommon and has frequently been confused with nonprogressive ventriculomegaly in the past. Psychometric evaluations, neurological findings, and neuropathologic reports from the literature are critically reviewed. It is clear that a significant number of patients with the Apert syndrome are mentally retarded. It is suggested that malformations of the central nervous system may be responsible for most cases.

Acrocephalosyndactylia↗

PubMed1993

Lethal multiple pterygium syndrome: report of a case with neurological anomalies.

We report on a 22-week female fetus with multiple pterygia, congenital joint contractures, muscle hypoplasia, cystic hygroma, hydrops, pulmonary and cardiac hypoplasia, facial anomalies, and growth retardation. Examination also documented microcephaly, brain immaturity, and severe cerebellar and pontine hypoplasia with absence of the pyramidal tracts. The spinal cord showed a marked decrease in size of all white matter tracts. The muscles were markedly hypoplastic. The relation of the neurological findings to the development of the syndrome is discussed.

Abnormalities, Multiple↗

PubMed2004

A founder effect in three large Newfoundland families with a novel clinically variable spastic ataxia and supranuclear gaze palsy.

A distinctive slowly progressive neurodegenerative disorder, which falls under a new category of neurological diseases, the hereditary spastic ataxias (HSA), is described in three independently ascertained Newfoundland kindreds. HSA is a heterogeneous group of disorders in which pyramidal tract features overlap cerebellar characteristics. The families are assumed to have the same condition as, although apparently unrelated, all originate in a historically isolated cluster of rural communities and link to the same locus at 12p13, SAX1. Clinically the phenotype is very variable but lower limb hypertonicity and hyperreflexia are early and prominent generally preceded by eye movement abnormality, an impaired vertical downward saccade and a typical involuntary head jerk. These are followed by variable levels of ataxia, dysarthria, and dysphagia. Onset occurs in the first two decades and can be detected in most by early adulthood. Significant mobility problems are present by the fourth decade with a broad based ataxic and spastic gait. MRI scans of brain and spinal cord were normal. Neuropathology showed degeneration of corticospinal tracts and posterior columns and midbrain neuronal loss. The phenotype is striking in its diversity among and within families and the variability of expression can be observed within the same sibship. Pedigree analysis shows no evidence of anticipation or any sex differences in severity. The condition is unusually prevalent in the province of Newfoundland, which is characteristic of a founder effect followed by isolation and large family size. Fine mapping efforts have reduced the critical interval of the SAX1 locus to 1.9Mb. Identification of the SAX1 gene will help to clarify the pathogenesis of this type of HSA.

Base Sequence↗

PubMed1983

A sibship with neuroaxonal dystrophy and renal tubular acidosis: a new syndrome?

The clinical and pathological features of three siblings from nonconsanguineous parents are described. Two of the children died at 6 1/2 and 7 months of age of a central nervous system disorder characterized by severe behavioral retardation, hypotonia, and pyramidal tract signs. The third child, now 8 years old, has global mental retardation, inability to talk, marked tremors, and gait disturbances. All children exhibited inability to concentrate or acidify the urine, with growth delay partially corrected in the living child by alkali therapy. Computed tomographic scans revealed hyperdense lesions in the thalamus of one of the siblings and more striking hyperdensity of the basal ganglia in the eldest child. Findings at postmortem examination in two children, and by renal and sural nerve biopsy in the third, include swollen axons in the internal capsule and peripheral nerves, and neurons with iron-staining deposits, gliosis, and macrophages containing lipofuscin pigments in the brain. The renal findings include material positive for periodic acid-Schiff and hyperdense granular deposits in renal tubules.

Acidosis, Renal Tubular↗

PubMed1985

Neurological findings in triosephosphate isomerase deficiency.

Two siblings with hemolytic anemia caused by triosephosphate isomerase deficiency developed a progressive neurological syndrome featuring dystonic movements, tremor, pyramidal tract signs, and evidence of spinal motor neuron involvement. Intelligence was unaffected. The findings in these patients and in 14 previously published cases indicate that neurological manifestations are an integral part of the disorder and suggest that specific structures in the basal ganglia, brainstem, and spinal cord bear the brunt of the pathological process, which does not affect the cerebral cortex.

Anemia, Hemolytic↗

PubMed1985

Progressive encephalopathy in children with acquired immune deficiency syndrome.

We are reporting the cases of four children with a diagnosis of acquired immune deficiency syndrome (AIDS) who demonstrated a progressive encephalopathy manifested by loss of motor milestones or intellectual abilities, and weakness with pyramidal tract signs. Two patients were ataxic. One child was cortically blind and suffered myoclonic jerks before his death. Two of the patients had isolated seizures at some time during the disease course. Two patients developed secondary microcephaly and all four patients showed cortical atrophy on computed tomographic scanning. Three of the patients died. Postmortem neuropathological findings included gross cortical atrophy, microglial nodules, and intranuclear inclusions, as are described in the subacute encephalitis reported in adult AIDS patients. We propose that the possible pathogenetic mechanisms of this encephalopathy include opportunistic or persistent viral infection of the brain.

Acquired Immunodeficiency Syndrome↗

PubMed1985

Neurological complications in infants and children with acquired immune deficiency syndrome.

Neurological complications occurred in 6 children, aged 6 months to 5 years, with acquired immune deficiency syndrome who were followed for 14 months. The most frequent manifestations included encephalopathies, acquired microcephaly, and pyramidal tract signs. Computed tomographic examinations showed variable degrees of cortical atrophy with ventricular dilatation and calcification. Electrophysiological abnormalities were demonstrated. Two children had documented central nervous system infections. Neurological deterioration resulted in dementia in 3 children. Cognitive impairment and developmental delays were evident in the other 3. Postmortem examination of the 3 children who died showed subacute cytomegalovirus encephalitis in 1; nonspecific hemispheric white matter changes, calcific vasopathy of the basal ganglia, and striking bilateral corticospinal tract degeneration in the second; and extensive calcific vasopathy of the basal ganglia and frontal centrum semiovale, and bilateral attenuation of the frontopontine and corticospinal tracts in the third.

Acquired Immunodeficiency Syndrome↗

PubMed1986

N-acetyl-beta-hexosaminidase beta locus defect and juvenile motor neuron disease: a case study.

A patient with partial deficiency of N-acetyl-beta-hexosaminidase (Hex) developed a progressive motor neuron syndrome beginning at age 7, characterized by dysarthria, muscle wasting, fasciculations, and pyramidal tract dysfunction. Minor clinical features have included tremor and late distal sensory abnormalities. Rectal biopsy at age 24 demonstrated membranous cytoplasmic bodies in submucosal ganglion cells. Biochemical evaluation revealed nearly absent Hex B activity in serum, leukocytes, and fibroblasts, with partial Hex A activity in serum and leukocytes, and low normal Hex A activity in fibroblasts. Motor neuron disease can be a presentation of a Hex beta locus defect, in addition to the previously recognized Hex alpha locus defects.

Adult↗

PubMed1986

Cortical potentials related to voluntary and passive finger movements recorded from subdural electrodes in humans.

Movement-related potentials were recorded from subdural electrodes placed on the precentral and postcentral cortex in 3 patients undergoing operation for intractable epilepsy. With self-initiated index finger movement, a negative potential of 25 to 50 microvolts in amplitude, preceding onset of the electromyographic activity by 60 to 95 ms (or onset of movement by 150 to 230 ms), was recorded from the hand somatosensory postrolandic area in all 3 patients. A similar potential preceding the movement was recorded from the precentral hand motor area in one subject who was the only patient in whom the precentral electrodes were placed on the hand motor area. Following active and passive movements, a clearly defined positivity (18 to 32 ms after a photometer trigger) that reversed phase across the central fissure was recorded. The premovement potentials are most probably generated by pyramidal tract neurons and motor-function-related neurons located in the post- and prerolandic areas. The postmovement positivity is most probably due to short-latency kinesthetic reafferent activation of the posterior bank of the central fissure (equivalent to P2 of the somatosensory evoked potentials).

Brain Mapping↗

PubMed1987

Endemic tropical spastic paraparesis associated with human T-lymphotropic virus type I: a clinical and seroepidemiological study of 25 cases.

Tropical spastic paraparesis (TSP) is a common myeloneuropathy with primary and predominant involvement of the pyramidal tract and minimal sensory loss. The epidemic form of TSP is related to toxic nutritional factors, but the endemic form occurs in clusters in tropical areas, especially in India, Africa, the Seychelles, Colombia, and areas of the Caribbean. We describe the clinical and epidemiological features of 25 TSP patients from Martinique (French West Indies) with serum antibodies to human T-lymphotropic virus type I (HTLV-I). Furthermore, all 11 patients who were seropositive for HTLV-I had specific HTLV-I antibodies in their CSF. All were women. The age of onset varied from 25 to 60 years (mean, 45 years). The main clinical features are spastic paraparesis or paraplegia with spasticity of the upper limbs, minimal sensory loss, and bladder dysfunction. Minimal estimated incidence and prevalence are 1 per 100,000 inhabitants per year and 8 per 100,000, respectively. Seventeen percent of the relatives of patients with HTLV-I-associated TSP have HTLV-I antibodies (1 husband and 7 children). In Martinique, the prevalence of HTLV-I antibodies in the general population is about 2% and reaches 10% for neurological disorders other than TSP. Since our initial report, the association between spastic paraparesis and HTLV-I has been confirmed in Jamaica, Colombia, and Japan, suggesting the neurotropism of this lymphotropic human retrovirus.

Adult↗

PubMed1990

A disorder of axonal development, necrotizing myopathy, cardiomyopathy, and cataracts: a new familial disease.

We report severe congenital encephalopathy and profound hypotonia associated with necrotizing myopathy, cardiomyopathy, and cataracts in 3 infants, including 2 sisters. Brain scans suggested agenesis of the corpus callosum. Neuropathological findings consisted of severe atrophy of the corpus callosum (not the usual agenesis with longitudinal callosal bundles), atrophy of the white matter, and absence of pyramidal tracts in the medulla. Multiple axonal swellings were present in the white matter and in Purkinje cells. Except for the corpus subthalamicum, gray matter structures were preserved. These findings are considered to be the expression of a primary disorder of axonal development leading to a reduction in interneuronal synaptic contacts. It is suggested that the anomaly may be due to an extension of the normal phenomenon of axonal elimination, related to a primary defect of the axonal cytoskeleton. The concept of a primary axonal disorder may also apply to other, mostly familial, conditions with progressive atrophy of the cerebral white matter and corpus callosum.

Atrophy↗

PubMed1992

Rapidly progressive autosomal dominant parkinsonism and dementia with pallido-ponto-nigral degeneration.

We describe a family with nearly 300 members over 8 generations with 32 affected individuals who have an autosomal dominant neurodegenerative disease characterized by progressive parkinsonism with dystonia unrelated to medications, dementia, ocular motility abnormalities, pyramidal tract dysfunction, frontal lobe release signs, perseverative vocalizations, and urinary incontinence. The course is exceptionally aggressive; symptom onset and death consistently occur in the fifth decade. Positron emission tomographic studies with [18F]6-fluoro-L-dopa (6FD) were performed in 4 patients and 7 individuals at risk for development of the disease. All affected subjects had markedly reduced striatal uptake of 6FD (p less than 0.001). All individuals at risk had normal striatal uptake, but high 6FD uptake rate constants were noted in 3 of the 7 studied. Autopsy findings revealed severe neuronal loss with gliosis in substantia nigra, pontine tegmentum, and globus pallidus, with less involvement of the caudate and the putamen. There were no plaques, tangles, Lewy bodies, or amyloid bodies. This kindred appears to represent a neurodegenerative disease not heretofore described. We propose the following name for this new genetic disease: autosomal dominant parkinsonism and dementia with pallido-ponto-nigral degeneration.

Adult↗