1/437. Transplant of cultured neuron-like differentiated chromaffin cells in a Parkinson's disease patient. A preliminary report.BACKGROUND: Treatment of Parkinson's Disease (PD) has been attempted by others by transplanting either the patient's own adrenal medullary tissue or fetal substantia nigra into caudate or putamen areas. However, the difficulties inherent in using the patient's own adrenal gland, or the difficulty in obtaining human fetal tissue, has generated the need to find alternative methods. methods: We report here of an alternative to both procedures by using as transplant material cultured human adrenal chromaffin cells differentiated into neuron-like cells by extremely low frequency magnetic fields (ELF MF). RESULTS: The results of this study show that human differentiated chromaffin cells can be grafted into the caudate nucleus of a PD patient, generating substantial clinical improvement, as measured by the Unified Rating Scale for PD, which correlated with glucose metabolism and D2 DA receptor increases as seen in a PET scan, while allowing a 70% decrease in L-Dopa medication. DISCUSSION: This is the first preliminary report showing that transplants of cultured differentiated neuron-like cells can be successfully used to treat a PD patient.- - - - - - - - - - ranking = 1keywords = neuron (Clic here for more details about this article) |
2/437. Parkinson's syndrome after closed head injury: a single case report.A 36 year old man, who sustained a skull fracture in 1984, was unconscious for 24 hours, and developed signs of Parkinson's syndrome 6 weeks after the injury. When assessed in 1995, neuroimaging disclosed a cerebral infarction due to trauma involving the left caudate and lenticular nucleus. Parkinson's syndrome was predominantly right sided, slowly progressive, and unresponsive to levodopa therapy. reaction time tests showed slowness of movement initiation and execution with both hands, particularly the right. Recording of movement related cortical potentials suggested bilateral deficits in movement preparation. Neuropsychological assessment disclosed no evidence of major deficits on tests assessing executive function or working memory, with the exception of selective impairments on the Stroop and on a test of self ordered random number sequences. There was evidence of abulia. The results are discussed in relation to previous literature on basal ganglia lesions and the effects of damage to different points of the frontostriatal circuits.- - - - - - - - - - ranking = 0.016865662330787keywords = lateral (Clic here for more details about this article) |
3/437. Tau pathology in a family with dementia and a P301L mutation in tau.Familial forms of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17) have recently been associated with coding region and intronic mutations in the tau gene. Here we report our findings on 2 affected siblings from a family with early-onset dementia, characterized by extensive tau pathology and a Pro to Leu mutation at codon 301 of tau. The proband, a 55-year-old woman, and her 63-year-old brother died after a progressive dementing illness clinically diagnosed as alzheimer disease. Their mother, 2 sisters, maternal aunt and uncle, and several cousins were also affected. autopsy in both cases revealed frontotemporal atrophy and degeneration of basal ganglia and substantia nigra. Sequencing of exon 10 of the tau gene revealed a C to T transition at codon 301, resulting in a Pro to Leu substitution. Widespread neuronal and glial inclusions, neuropil threads, and astrocytic plaques similar to those seen in corticobasal degeneration were labeled with a battery of antibodies to phosphorylation-dependent and phosphorylation-independent epitopes spanning the entire tau sequence. Isolated tau filaments had the morphology of narrow twisted ribbons. Sarkosyl-insoluble tau exhibited 2 major bands of 64 and 68 kDa and a minor 72 kDa band, similar to the pattern seen in a familial tauopathy associated with an intronic tau mutation. These pathological tau bands predominantly contained the subset of tau isoforms with 4 microtubule-binding repeats selectively affected by the P301L missense mutation. Our findings emphasize the phenotypic and genetic heterogeneity of tauopathies and highlight intriguing links between FTDP-17 and other neurodegenerative diseases.- - - - - - - - - - ranking = 0.16666666666667keywords = neuron (Clic here for more details about this article) |
4/437. Immunohistochemical and subcellular localization of Parkin protein: absence of protein in autosomal recessive juvenile parkinsonism patients.Autosomal recessive juvenile parkinsonism (AR-JP) is a distinct clinical entity characterized by a selective degeneration of nigral neurons. Recently, the parkin gene responsible for AR-JP has been identified. Now, we report the subcellular localization of Parkin protein in patients with AR-JP or Parkinson's disease (PD) and in controls by immunoblotting and immunohistochemistry using antibodies raised against the Parkin molecule. Parkin protein was absent in all regions of the brains of patients with AR-JP. Parkin protein was not decreased in the brains of sporadic PD patients. Immunoreactivity was detected in a few lewy bodies. Parkin protein was located in both the Golgi complex and cytosol.- - - - - - - - - - ranking = 0.16666666666667keywords = neuron (Clic here for more details about this article) |
5/437. Numerous and widespread alpha-synuclein-negative lewy bodies in an asymptomatic patient.lewy bodies (LB) and pale bodies (PB), their putative precursors, can be found in a spectrum of diseases characterized by parkinsonism and/or dementia. Furthermore, LB are occasionally observed in some other neurodegenerative diseases and in normal aging. Classical LB are typically found in the brain stem, especially in the substantia nigra, where these inclusions are associated with neuronal loss and clinical signs of idiopathic Parkinson's disease (PD). The so-called cortical LB occur in the cerebral cortex, amygdala and claustrum with little or no neuronal loss and are clinically associated with dementia in dementia with LB (DLB). We describe a patient without apparent clinical signs of parkinsonism and/or dementia, whose brain contained numerous classical-like LB, pale inclusions with features of PB and transitions between these two. These inclusions had similar immunohistological (ubiquitin positive; neurofilament positive; tau negative) and ultrastructural features as the LB in PD and DLB except for the lack of immunoreactivity for alpha-synuclein. The pons and cerebral cortex showed the highest number of LB, up to 165/1.76 mm2. These numbers were contrasted by the lack of obvious neuronal loss or gliosis. The absence of alpha-synuclein reactivity in the LB in this symptomless patient corroborates the hypothesis that alpha-synuclein accumulation in LB is an important step in neurodegeneration in PD and DLB, but tones down the role of alpha-synuclein in LB formation in general. This patient seems to represent a new variant in the spectrum of diseases associated with LB.- - - - - - - - - - ranking = 0.5keywords = neuron (Clic here for more details about this article) |
6/437. Diffuse lewy body disease presenting as multiple system atrophy.OBJECTIVES: The majority of patients with diffuse lewy body disease have cognitive or psychiatric manifestations as part of their initial presentation. A sizable minority present with parkinsonian features alone. Autonomic features may also occur, typically after the development of cognitive changes. We aim to demonstrate that diffuse lewy body disease may rarely also present with parkinsonism accompanied by marked autonomic dysfunction in the absence of significant cognitive or psychiatric abnormalities. methods: Case report based on a retrospective chart review and neuropathological examination. RESULTS: We report on a patient in whom a clinical diagnosis of multiple system atrophy was made based on a presentation of parkinsonism with prominent and early autonomic involvement. The former included postural tremor, rigidity and bradykinesia, while the latter consisted of repeated falls due to orthostasis and the subsequent development of urinary incontinence midway through the course of her illness. She was poorly tolerant of dopaminergic therapy due to accentuated orthostasis. Benefit from levodopa was limited and only evident when attempted withdrawal resulted in increased rigidity. There was no history of spontaneous or drug-induced hallucinations, delusions or fluctuating cognition, and in contrast to the prominence and progression of her parkinsonian and autonomic features over the first several years, cognitive impairment did not occur until the final stages of her illness, seven years after the onset of initial symptoms. Neuropathological examination revealed numerous lewy bodies in both neocortical as well as subcortical structures consistent with a diagnosis of diffuse lewy body disease. There was marked neuronal loss in the substantia nigra as well as the autonomic nuclei of the brainstem and spinal cord. CONCLUSIONS: In addition to cognitive, psychiatric, and parkinsonian presentations, diffuse lewy body disease may present with parkinsonism and prominent autonomic dysfunction, fulfilling proposed criteria for the striatonigral form of MSA.- - - - - - - - - - ranking = 0.16666666666667keywords = neuron (Clic here for more details about this article) |
7/437. From off-period dystonia to peak-dose chorea. The clinical spectrum of varying subthalamic nucleus activity.The effect of chronic bilateral high-frequency stimulation of the subthalamic nucleus (STN) on levodopa-induced dyskinaesias was investigated in eight patients with fluctuating Parkinson's disease complicated by functionally disabling off-period dystonia. All of the patients also had severe diphasic and peak-dose chorea, so that it was possible to study the effect of high-frequency stimulation on the different types of levodopa-induced dyskinaesias. Off-period fixed dystonia was reduced by 90% and off-period pain by 66%. After acute levodopa challenge, high-frequency stimulation of the STN reduced diphasic mobile dystonia by 50% and peak-dose choreic dyskinaesias by 30%. The effect of bilateral high-frequency stimulation of the STN on the Unified Parkinson's Disease Rating Scale motor score had the same magnitude as the preoperative effect of levodopa. This allowed the levodopa dose to be reduced by 47%. The combination of reduced medication and continuous high-frequency stimulation of the STN reduced the duration of on-period diphasic and peak-dose dyskinaesias by 52% and the intensity by 68%. Acute high-frequency stimulation of the STN mimics an acute levodopa challenge, concerning both parkinsonism and dyskinaesias, and suppresses off-period dystonia. Increasing the voltage can induce repetitive dystonic dyskinaesias, mimicking diphasic levodopa-induced dyskinaesias. A further increase in voltage leads to a shift from a diphasic-pattern dystonia to a peak-dose pattern choreodystonia. Chronic high-frequency stimulation of the STN also mimics the benefit of levodopa on parkinsonism and improves all kinds of levodopa-induced dyskinaesias to varying degrees. Off-period dystonia, associated with neuronal hyperactivity in the STN is directly affected by stimulation and disappears immediately. The effect of chronic high-frequency stimulation of the STN on diphasic and peak-dose dyskinaesias is more complex and is related directly to the functional inhibition of the STN and indirectly to the replacement of the pulsatile dopaminergic stimulation by continuous functional inhibition of the STN. Chronic high-frequency stimulation of the STN allows a very gradual increase in stimulation parameters with increasing beneficial effect on parkinsonism while reducing the threshold for the elicitation of stimulation-induced dyskinaesias. In parallel with improvement of parkinsonism, the levodopa dose can be gradually decreased. As diphasic dystonic dyskinaesias are improved to a greater degree than peak-dose dyskinaesias, both direct and indirect mechanisms may be involved. Peak-dose choreatic dyskinaesias, associated with little evidence of parkinsonism and thus with low neuronal activity in the STN, are improved, mostly indirectly. Fixed off-period dystonia, mobile diphasic dystonia and peak-dose choreodystonia seem to represent a continuous clinical spectrum reflecting a continuous spectrum of underlying activity patterns of STN neurons.- - - - - - - - - - ranking = 0.66460709773864keywords = neuron, motor, lateral (Clic here for more details about this article) |
8/437. Deterioration in parkinsonism with low-dose pergolide.The administration of dopamine agonists can have a role early in the course of Parkinson's disease, in an attempt to reduce the frequency of long-term motor complications associated with the use of levodopa. After treatment with dopamine agonists has begun, gradual dose escalation is recommended to reduce the incidence of side effects; at low doses, parkinsonian symptoms significantly decline in some patients, only to improve as the dose increases. We report a number of such patients and discuss the possible pathogenesis of this motor deterioration.- - - - - - - - - - ranking = 0.26175154615414keywords = motor (Clic here for more details about this article) |
9/437. Treatment with AC pulsed electromagnetic fields improves olfactory function in Parkinson's disease.Olfactory dysfunction is a common symptom of Parkinson's disease (PD). It may manifest in the early stages of the disease and infrequently may even antedate the onset of motor symptoms. The cause of olfactory dysfunction in PD remains unknown. Pathological changes characteristic of PD (i.e., lewy bodies) have been demonstrated in the olfactory bulb which contains a large population of dopaminergic neurons involved in olfactory information processing. Since dopaminergic drugs do not affect olfactory threshold in PD patients, it has been suggested that olfactory dysfunction in these patients is not dependent on dopamine deficiency. I present two fully medicated Parkinsonian patients with long standing history of olfactory dysfunction in whom recovery of smell occurred during therapeutic transcranial application of AC pulsed electromagnetic fields (EMFs) in the picotesla flux density. In both patients improvement of smell during administration of EMFs occurred in conjunction with recurrent episodes of yawning. The temporal association between recovery of smell and yawning behavior is remarkable since yawning is mediated by activation of a subpopulation of striatal and limbic postsynaptic dopamine D2 receptors induced by increased synaptic dopamine release. A high density of dopamine D2 receptors is present in the olfactory bulb and tract. Degeneration of olfactory dopaminergic neurons may lead to upregulation (i.e., supersensitivity) of postsynaptic dopamine D2 receptors. Presumably, small amounts of dopamine released into the synapses of the olfactory bulb during magnetic stimulation may cause activation of these supersensitive receptors resulting in enhanced sense of smell. Interestingly, in both patients enhancement of smell perception occurred only during administration of EMFs of 7 Hz frequency implying that the release of dopamine and activation of dopamine D2 receptors in the olfactory bulb was partly frequency dependent. In fact, weak magnetic fields have been found to cause interaction with biological systems only within narrow frequency ranges (i.e., frequency windows) and the existence of such frequency ranges has been explained on the basis of the cyclotron resonance model.- - - - - - - - - - ranking = 0.4642091064104keywords = neuron, motor (Clic here for more details about this article) |
10/437. A mutation at codon 279 (N279K) in exon 10 of the Tau gene causes a tauopathy with dementia and supranuclear palsy.Recently intronic and exonic mutations in the Tau gene have been found to be associated with familial neurodegenerative syndromes characterized not only by a predominantly frontotemporal dementia but also by the presence of neurological signs consistent with the dysfunction of multiple subcortical neuronal circuitries. Among families, the symptomatology appears to vary in quality and severity in relation to the specific Tau gene mutation and often may include parkinsonism, supranuclear palsies, and/or myoclonus, in addition to dementia. We carried out molecular genetic and neuropathological studies on two patients from a French family presenting, early in their fifth decade, a cognitive impairment and supranuclear palsy followed by an akinetic rigid syndrome and dementia. The proband died severely demented 7 years after the onset of the symptoms; currently, his brother is still alive although his disease is progressing. In both patients, we found a Tau gene mutation in exon 10 at codon 279, resulting in an asparagine to lysine substitution (N279K). Neuropathologically, widespread neuronal and glial tau accumulation in the cortex, basal ganglia, brain stem nuclei as well as in the white matter were the hallmark of the disease. These deposits were shown by immunohistochemistry and immunoelectron microscopy, using a battery of antibodies to phosphorylation-dependent and phosphorylation-independent epitopes present in multiple tau regions. In the neocortex, tau-immunopositive glial cells were more numerous than immunopositive neurons; the deeper cortical layers as well as the white matter adjacent to the cortex contained the largest amount of immunolabeled glial cells. In contrast, some brain stem nuclei contained more neurons with tau deposits than immunolabeled glial cells. The correlation of clinical, neuropathological and molecular genetic findings emphasize the phenotypic heterogeneity of diseases caused by Tau gene mutations. Furthermore, to test the effect of the N279K mutation and compare it with the effect of the P301L exon 10 mutation on alternative splicing of Tau exon 10, we used an exon amplification assay. Our results suggest that the N279K mutation affects splicing similar to the intronic mutations, allowing exon 10 to be incorporated more frequently in the Tau transcript.- - - - - - - - - - ranking = 0.66666666666667keywords = neuron (Clic here for more details about this article) |
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