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PubMed1987

Hereditary generalized amyloidosis with polyneuropathy. Clinicopathological study of 65 Japanese patients.

A clinicopathological study was made on 65 patients from a small area of Nagano Prefecture, Japan, with hereditary generalized amyloidosis with polyneuropathy to clarify the clinical variety of the disease. Forty-five patients from Ogawa village showed similar clinical features. The age of onset ranged widely from 16 to 62 years. The main neurological manifestations were polyneuropathy starting in the legs and autonomic dysfunction. Lower cranial nerves were also affected in the advanced stages. Severe cardiac and renal involvement was uncommon. All these clinical features are consistent with type I familial amyloid polyneuropathy (FAP). The remaining 20 patients from five unrelated kinships showed unique clinical pictures. Two families from Ogawa village had type I FAP, but 4 out of the 5 affected patients showed marked nephropathy with heavy proteinuria from an early stage. Of the three other families, one, with 10 patients, was notable for the involvement of the central nervous system. Most of the patients showed cerebellar ataxia and pyramidal tract signs in addition to a sensorimotor and autonomic peripheral neuropathy. Another family had 2 siblings who had severe amyloid heart disease from the onset and developed polyneuropathy with autonomic features at an advanced stage. In the third family, onset occurred in the sixth decade in all 3 patients and the course was mild in 2, although the clinical features were those of typical type I FAP. Immunohistochemical study revealed that the amyloid fibril proteins in the patients with all four unusual clinical phenotypes were related to plasma prealbumin. The most common form of hereditary generalized amyloidosis in Japan is type I FAP, but the disease shows considerable variety in the age of onset and involves more systemic organs than previously recognized. The newly recognized clinical forms of hereditary generalized amyloidosis with severe amyloid heart disease or central nervous dysfunction indicate clinical heterogeneity of hereditary amyloidosis with polyneuropathy.

Adolescent↗
PubMed1987

Motor cortex stimulation in intact man. 2. Multiple descending volleys.

Using an isometric strain gauge, we measured the twitch force produced in the first dorsal interosseous (FDI) muscle by a single anodal shock to the contralateral scalp. At high intensities of stimulation this twitch can greatly exceed the force produced by supramaximal stimulation of peripheral nerve. This indicates that a single cortical shock can cause repetitive firing of some or all FDI motoneurons. Such repetitive firing was demonstrated using a collision technique in which a supramaximal ulnar nerve stimulus was given at the wrist shortly after a cortical shock. The antidromic volley from the peripheral nerve stimulation failed to obliterate completely the response to cortical stimulation. Additional EMG activity was visible in the normally silent period between ulnar M and F waves. This activity must have been due to the presence of repetitive volleys of activity set up in spinal motoneurons by the cortical shock. Such activity summates with the twitch produced by the ulnar M wave to produce a very large force twitch of the muscle. Multiple firing of some motoneurons can be observed in some individuals at cortical stimulation intensities below that necessary to evoke activity in all the motoneurons in the FDI pool. Multiple firing probably was caused by repetitive excitatory inputs impinging on spinal motoneurons. These could be demonstrated using poststimulus time histogram techniques on single motor units. Low intensities of cortical stimulation produced a single short duration (mean 1.8 ms) peak of increased motor unit firing 20 to 30 ms after the shock. At high intensities, this was followed by extra peaks some 4 to 5 ms later. H reflex testing showed that the threshold of the initial descending volley, produced by the cortical stimulus was uninfluenced by a voluntary contraction. These results are discussed with reference to the D and I waves recorded from pyramidal tract after anodal stimulation of the exposed cortex in animals.

Biomechanical Phenomena↗
PubMed1993

Cortical function in amyotrophic lateral sclerosis. A positron emission tomography study.

Positron emission tomography was used to measure regional cerebral blood flow (rCBF) in 12 patients with amyotrophic lateral sclerosis (ALS) and six age-matched controls. Scans were performed at rest, and while subjects performed stereotyped and freely selected movements of a joystick with their right hand. Statistical parametric mapping was used to determine significant differences in rCBF between the two groups at rest and during activation. The ALS group showed no significant difference in global cerebral blood flow at rest compared with controls. However, rCBF at rest was significantly (P < 0.01) reduced in the ALS group in the primary sensorimotor cortex, the lateral premotor cortex, the supplementary motor area, the anterior cingulate cortex, the paracentral lobule and the superior and inferior parietal cortex. Comparison of the increase in rCBF caused by freely selected joystick movements over the resting state between the two groups of subjects showed significantly (P < 0.001) greater activation in ALS patients in the ventral third (face area) of the contralateral primary sensorimotor cortex and in the adjacent contralateral ventral premotor and parietal association cortices; significantly (P < 0.01) greater activation of the contralateral anterior insula and the ipsilateral anterior cingulate cortex (dorso-caudal area 24) was also present in ALS patients. When a comparison of the rCBF response to the free selection task with that to the stereotyped task was performed between the two groups of subjects, ALS patients showed significantly impaired (P < 0.01) activation of the rostral anterior cingulate cortex (area 32), medial prefrontal cortex (area 10), left parahippocampal gyrus and retrosplenial cortex. The pattern of reduced rCBF at rest in ALS patients probably reflects a combination of neuronal loss in all areas of cortex projecting through the pyramidal tract together with loss of projections from the sensorimotor cortex to the motor association areas. The expansion of the upper limb output zone of the sensorimotor cortex in ALS patients during contralateral upper limb movement may represent cortical reorganization in response to Betz cell loss or corticospinal tract disruption. Abnormal recruitment of non-primary motor areas may also represent functional adaptation to a corticospinal tract lesion. Focally impaired activation of the medial prefrontal cortex and parahippocampal gyrus in ALS patients during the process of internal generation of movement could underlie the frontal lobe cognitive deficits reported in previous neuropsychological studies of ALS.

Adult↗
PubMed1994

Autosomal dominant cerebellar ataxia with pigmentary macular dystrophy. A clinical and genetic study of eight families.

We describe 54 members of eight families with a distinct autosomal dominant cerebellar ataxia associated with visual failure secondary to a pigmentary macular dystrophy. The presenting symptom was ataxia in two-thirds of patients and visual failure or both in the remainder. The macular abnormalities were often subtle in early cases, even in some with moderately reduced visual acuity. Other neurological features included pyramidal tract signs and a supranuclear ophthalmoplegia with progressive saccadic palsy. Ages of onset and clinical course were very variable, even within families, and included a rapidly progressive, infantile-onset phenotype. Pedigree analysis showed the existence of non-manifesting obligate carriers and anticipation in the offspring of affected fathers; transmission of the disease to severe, infantile-onset cases was always from an affected father. Similar genetic phenomena have been reported in myotonic dystrophy and Huntington's disease and it is likely that the gene mutation in this condition will similarly consist of an unstable trinucleotide repeat expansion.

Adolescent↗
PubMed1995

Spinal cord morphology and pathology in ossification of the posterior longitudinal ligament.

We analysed nine autopsy cases of ossification of the posterior longitudinal ligament (OPLL) to elucidate the relationship between morphology and pathology of the spinal cord. The cross-sectional shape of the spinal cord at the most severely affected segment was classified into two categories: boomerang (convex lateral surfaces and concave anterior surface) and triangular (angular lateral surfaces and flat anterior surface). In the cases with a boomerang shape, even when the compression was severe, major pathological changes were restricted to the grey matter and the white matter was relatively well preserved. No secondary descending degeneration of the lateral columns was seen, and ascending degeneration of the posterior column was restricted to the fasciculus cuneatus whose fibres were derived from the affected segments. In the cases with a triangular shape, pathological changes were more severe, both white matter and grey matter were involved, and only the anterior columns were free of pathological changes. There were severe pathological changes over more than one segment, and both descending degeneration of the lateral pyramidal tracts and ascending degeneration of the posterior column, including the fasciculus gracilis, were observed. The transverse area of the spinal cord was > 60% of normal in most of the cases with a boomerang shape, but it was reduced to < 60% of normal in more than one segment in the cases with a triangular shape. The compression ratio of the spinal cord (sagittal diameter/transverse diameter x 100%) was not related to pathological changes. In conclusion, a triangular-shaped spinal cord with transverse area of < 60% of normal in more than one segment appeared to be associated with severe and irreversible pathological changes in cases of OPLL.

Adult↗
PubMed1996

The course of cortico-hypoglossal projections in the human brainstem. Functional testing using transcranial magnetic stimulation.

Cortico-hypoglossal projections were investigated in 11 patients with unifocal ischaemic lesions of different brainstem levels using transcranial magnetic stimulation. Lesion topography was documented by MRI studies. In seven patients the projections to the ipsi- and contralateral hypoglossal nuclei were separately affected. Pontine lesions at the ventral paramedian base close to the midline affect the contralateral projections while lateral lesions at the pontine base affect the ipsilateral projections. Lesions of the paramedian dorsal pontine base do not involve the cortico-hypoglossal projections. Our findings indicate that the cortico-hypoglossal fibres branch off the main ventral pyramidal tract. Lesions of the dorso- and mediolateral medulla impair only the ipsilateral projections. We conclude that ipsilateral projections enter the hypoglossal nucleus from its lateral aspect and that the contralateral projections cross the midline at the pontomedullary junction.

Aged↗
PubMed1996

Autosomal dominant cerebellar ataxia type I clinical features and MRI in families with SCA1, SCA2 and SCA3.

Sixty-five patients suffering from autosomal dominant cerebellar ataxia-I(ADCA-1) were subjected genotype phenotype correlation analysis using molecular genetic assignment to the spinocerebellar ataxia type 1, 2 or 3 (SCA1, -2 or -3) locus, clinical examination, eye movement recording and morphometric analysis of MRIs. Pyramidal tract signs, pale discs and dysphagia were more frequent in SCA1 compared SCA2 and SCA3 patients. Saccade velocity was reduced in 56% of SCA1 and all SCA2, but only in 30% of SCA3 patients. MRIs of SCA2 patients showed atrophy changes typical of severe olivopontocerebellar atrophy (OPCA). The morphological changes in SCA1 were similar but less pronounced. In contrast, SCA3 patients had only mild cerebellar and brain stem atrophy distinct from typical OPCA. The principal finding of this study is that mutations of the SCA2 and SCA3 gene cause phenotypes which can be distinguished in vivo by recording of eye movements and morphometric MRI analysis. Correlative plotting of saccade velocity and diameter of the middle cerebellar peduncle yields a clear separation of SCA2 and SCA3. Spinocerebellar ataxia type I falls into an intermediate range that overlaps with both SCA2 and SCA3. However, the clinical syndrome observed in SCA1 patients is different from that in SCA2 and SCA3.

Adult↗
PubMed2001

Does primary lateral sclerosis exist? A study of 20 patients and a review of the literature.

The question of whether primary lateral sclerosis (PLS) is a nosological entity distinct from amyotrophic lateral sclerosis (ALS) has been the subject of controversy since it was first described in the nineteenth century. PLS has been defined as a rare, non-hereditary disease characterized by progressive spinobulbar spasticity, related to the selective loss of precentral pyramidal neurones, with secondary pyramidal tract degeneration and preservation of anterior horn motor neurones. In the recent clinical literature, the frontier between ALS and neurodegenerative disease remains poorly defined. We studied 20 patients with a diagnosis of PLS. We carried out a variety of tests in order to determine the presence of a more diffuse neurodegenerative process. We also performed a longitudinal electrophysiological evaluation. Our clinical, electrophysiological and pathological investigations provide evidence that the disease has a heterogeneous clinical presentation and that degeneration is not restricted to the central motor system.

Adult↗
PubMed2003

Perception and production of biological movement in patients with early periventricular brain lesions.

Recent neuroimaging and psychophysical findings suggest that perception and production of human body motion share a common representational network. In the present study, we address the issue of whether early disorders in production of biological movement correspond to impairment in biological motion perception. By using the simultaneous masking paradigm, we examined visual sensitivity to biological motion in adolescents (aged 13-16 years) who were born very preterm (at 27-33 gestational weeks). In a confidence rating procedure, the presence of a point-light walking figure embedded in a moving mask was judged. The participants differed in their locomotion ability, ranging from normal to a complete walking disability exhibiting signs of leg-dominated bilateral spastic cerebral palsy (BS-CP) caused by periventricular leukomalacia (PVL). Irrespective of an ability to produce movement, patients with a similar extent of PVL in the parieto-occipital complex exhibit nearly the same sensitivity to biological motion. Sensitivity correlates negatively with the extent of PVL over the parieto-occipital complex, whereas neither the severity of motor disorder nor the severity of pyramidal tract affection relate significantly to the sensitivity index. The data suggest that perception of biological motion is not substantially affected by an observer's early restrictions in body movement. Instead, the findings favour the assumption that the common network for perception and production of biological motion might be inherent for the brain. Motor experience per se does not appear to be necessary for the visual analysis of human movement.

Adolescent↗
PubMed2003

Neural correlates of laughter and humour.

Although laughter and humour have been constituents of humanity for thousands if not millions of years, their systematic study has begun only recently. Investigations into their neurological correlates remain fragmentary and the following review is a first attempt to collate and evaluate these studies, most of which have been published over the last two decades. By employing the classical methods of neurology, brain regions associated with symptomatic (pathological) laughter have been determined and catalogued under other diagnostic signs and symptoms of such conditions as epilepsy, strokes and circumspect brain lesions. These observations have been complemented by newer studies using modern non-invasive imaging methods. To summarize the results of many studies, the expression of laughter seems to depend on two partially independent neuronal pathways. The first of these, an 'involuntary' or 'emotionally driven' system, involves the amygdala, thalamic/hypo- and subthalamic areas and the dorsal/tegmental brainstem. The second, 'voluntary' system originates in the premotor/frontal opercular areas and leads through the motor cortex and pyramidal tract to the ventral brainstem. These systems and the laughter response appear to be coordinated by a laughter-coordinating centre in the dorsal upper pons. Analyses of the cerebral correlates of humour have been impeded by a lack of consensus among psychologists on exactly what humour is, and of what essential components it consists. Within the past two decades, however, sufficient agreement has been reached that theory-based hypotheses could be formulated and tested with various non-invasive methods. For the perception of humour (and depending on the type of humour involved, its mode of transmission, etc.) the right frontal cortex, the medial ventral prefrontal cortex, the right and left posterior (middle and inferior) temporal regions and possibly the cerebellum seem to be involved to varying degrees. An attempt has been made to be as thorough as possible in documenting the foundations upon which these burgeoning areas of research have been based up to the present time.

Brain↗
PubMed2004

The phenotype of motor neuropathies associated with BSCL2 mutations is broader than Silver syndrome and distal HMN type V.

Silver syndrome is a rare autosomal dominant neurodegenerative disorder characterized by marked amyotrophy and weakness of small hand muscles and spasticity in the lower limbs. The locus for Silver syndrome (SPG17) was assigned to a 13 cM region on chromosome 11q12-q14 in a single large pedigree. We recently found heterozygous mutations in the Berardinelli-Seip congenital lipodystrophy (BSCL2, seipin) gene causing SPG17 and distal hereditary motor neuropathy type V (distal HMN V). Here we report the clinical features of two families with heterozygous BSCL2 mutations. Interestingly, both families show a clinical phenotype different from classical Silver syndrome, and in some patients the phenotype is also different from distal HMN V. Patients in the first family had marked spasticity in the lower limbs and very striking distal amyotrophy that always started in the legs. Patients in the second family had distal amyotrophy sometimes starting and predominating in the legs, but no pyramidal tract signs. These observations broaden the clinical phenotype of disorders associated with BSCL2 mutations, having consequences for molecular genetic testing.

Adolescent↗
PubMedDate not supplied

Trans-synaptically induced bursts in regular spiking non-pyramidal cells in deep layers of the cat motor cortex.

In deep layers of the cat motor cortex, we have investigated the properties of neurons displaying trans-synaptically induced bursts. In in vivo experiments, extracellularly recorded burst neurons were separated into two subtypes based on their dependence on stimulation sites, the medullary pyramid or the ventrolateral (VL) thalamic nucleus, from which bursts of 10-20 spikes were triggered. The spike amplitude attenuation and frequency adaptation during a burst were more prominent in pyramid-dependent burst neurons than in VL-dependent burst neurons. Intracellular recordings in in vivo experiments revealed that pyramid-dependent bursts emerged from a long-lasting depolarization, while each spike during a VL-dependent burst was narrow in half-width and was followed by a fast AHP, similar to fast spiking neurons. In in vitro slice experiments, intracellular recordings were obtained from neurons that displayed a burst of attenuated spikes emerging from a long-lasting depolarization, and were also obtained from fast spiking neurons. They were morphologically recovered to be multipolar cells with sparsely spiny dendrites and local axonal networks, suggesting that they are inhibitory interneurons. The multipolar neurons displaying bursts of attenuated spikes may mediate the recurrent inhibition of pyramidal tract cells.

Adaptation, Physiological↗
PubMed1996

Localization of the gene for rapidly progressive autosomal dominant parkinsonism and dementia with pallido-ponto-nigral degeneration to chromosome 17q21.

Rapidly progressive autosomal dominant parkinsonism and dementia with pallido-ponto-nigral degeneration (PPND) is a neurodegenerative disorder which begins later in life (> 30 years of age) and is characterized by rapidly progressive parkinsonism, dystonia, dementia, perservative vocalizations and pyramidal tract dysfunction. The disease is observed in a large American family that includes almost 300 members in nine generations with 34 affected individuals. In this kindred evidence for linkage to chromosome 17q21 was obtained with a maximum lod score of 9.08 for the D17S958 locus. Multilocus analysis positions the disease gene in an approximately 10 cM region between D17S250 and D17S943. Notably, the disease locus for a clinically distinct familial neurodegenerative disease named 'disinhibition-dementia-parkinsonism-amyotrophy complex' (DDPAC) was recently mapped to the same region of chromosome 17, suggesting that PPND and DDPAC may possibly originate from mutations in the same gene.

Adult↗
PubMed1988

Intrathecal synthesis of antibodies to human T lymphotropic virus type I and the presence of IgG oligoclonal bands in the cerebrospinal fluid of patients with endemic tropical spastic paraparesis.

Tropical spastic paraparesis (TSP), a neuromyelopathy predominantly involving the pyramidal tract and commonly observed in tropical and equatorial areas, was recently found to be associated with human T lymphotropic virus type I (HTLV-I). We investigated sera and cerebrospinal fluid (CSF) from 19 patients with TSP who were from the Caribbean area, French Guiana, and Africa. Our results showed an elevated intra-blood-brain barrier IgG synthesis rate and an elevated IgG index, with an increased HTLV-I antibody-to-albumin ratio and the presence of CSF oligoclonal bands in the majority of the patients. These data, in association with similar HTLV-I antibody patterns between patients with TSP who were from these three regions, strengthen the probable etiologic role of HTLV-I in the pathogenesis of such chronic neuromyelopathies.

Adult↗
PubMed2004

Clinical consequences of urea cycle enzyme deficiencies and potential links to arginine and nitric oxide metabolism.

Urea cycle disorders (UCD) are human conditions caused by the dysregulation of nitrogen transfer from ammonia nitrogen into urea. The biochemistry and the genetics of these disorders were well elucidated. Earlier diagnosis and improved treatments led to an emerging, longer-lived cohort of patients. The natural history of some of these disorders began to point to pathophysiological processes that may be unrelated to the primary cause of acute morbidity and mortality, i.e., hyperammonemia. Carbamyl phosphate synthetase I single nucleotide polymorphisms may be associated with altered vascular resistance that becomes clinically relevant when specific environmental stressors are present. Patients with argininosuccinic aciduria due to a deficiency of argininosuccinic acid lyase are uniquely prone to chronic hepatitis, potentially leading to cirrhosis. Moreover, our recent observations suggest that there may be an increased prevalence of essential hypertension. In contrast, hyperargininemia found in patients with arginase 1 deficiency is associated with pyramidal tract findings and spasticity, without significant hyperammonemia. An intriguing potential pathophysiological link is the dysregulation of intracellular arginine availability and its potential effect on nitric oxide (NO) metabolism. By combining detailed natural history studies with the development of tissue-specific null mouse models for urea cycle enzymes and measurement of nitrogen flux through the cycle to urea and NO in UCD patients, we may begin to dissect the contribution of different sources of arginine to NO production and the consequences on both rare genetic and common multifactorial diseases.

Animals↗
PubMed2002

S100A6 overexpression within astrocytes associated with impaired axons from both ALS mouse model and human patients.

Astrogliosis is one of the earliest pathological changes observed in neurodegenerative diseases in general and in amyotrophic lateral sclerosis (ALS) in particular. ALS is characterized by selective degeneration of motoneurons. There are 2 forms of the disease: sporadic ALS (SALS), comprising 90%-95% of cases, and familial ALS (FALS), comprising 5%-10% of cases. FALS is an age-dependent autosomal dominant disorder in which mutations in the homodimeric enzyme Cu/ Zn superoxide dismutase 1 (SOD1) is linked to the disease. The animal model for this disease is a transgenic mouse expressing the mutated human SOD1(G93A) gene. Here we show by immunohistochemistry and double immunofluorescence that astrocytes located near impaired axons of motoneurons that were selectively programmed to die overexpressed S100A6, a Ca2+/Zn2+ binding protein able to translocate into the nucleus. Transgenic mice overexpressing the mutated human SOD1 gene and patients suffering from SALS showed this selective astrocytic S100A6 expression. For instance, the pyramidal tract could be macroscopically detected on S100A6-labeled spinal cord and brainstem sections from SALS patients. Transgenic mice overexpressing the non-mutated SOD1 gene did not overexpress S100A6, although glial fibrillary associated protein astrogliosis was seen. Although these results do not give any clue about the beneficial or detrimental role played by S100A6, its induction may be assumed to appropriately serve some function(s).

Adult↗
PubMed2003

Aberrant neuronal migration in the brainstem of fukuyama-type congenital muscular dystrophy.

We examined the brainstem of 10 patients with Fukuyama-type congenital muscular dystrophy (FCMD). In the midbrain we noted leptomeningeal glioneuronal heterotopia (LGH) (n = 9) and intramural "micropolygyria" (n = 1) in the tectum, as well as tyrosine hydroxylase-positive ectopic neurons/fibers ventral to the cerebral peduncle (n = 3). In the pontomedullary region, glial fibrillary acidic protein-positive subpial tissue intermingled with neurons and myelinated fibers was present in the ventrolateral pontine surface in all cases and extended over the lateral surface of the upper medulla oblongata. This subpial gliotic band was often contiguous with the extra-pial LGH tissues. The gliotic band protruded from the ventrolateral pontine surface in 3 cases and appeared to include ectopic neurons of the pontine nucleus. Disarrangement of the arcuate nuclei (n = 3) was also noted in the medulla oblongata. We hypothesize that both the radial and tangential neuronal migration systems are disrupted in the FCMD brainstem in addition to altered neuronal migration in the cerebral and cerebellar cortex. Fukutin protein may play a part in the morphogenesis of certain neuronal structures in the brainstem and the dysplastic structure termed "aberrant pyramidal tract" in previous reports may essentially result from an ectopic migration of pontine nucleus neurons.

Adolescent↗
PubMed1977

Dysphagia due to vertical subluxation of the axis in rheumatoid arthritis.

Two patients with rheumatoid arthritis developed swallowing difficulties. These were mild in one case but severe in the other. Associated pyramidal tract signs and striking upward translocation of the dens made it seem probable that dysphagia was attributable to medullary compression despite the absence of other bulbar features. A history of dysphagia may therefore have serious implications for patients with rheumatoid disease.

Arthritis, Rheumatoid↗