Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0040822 (tremor)
 18,428 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Clinical and neuropathologic data in 45 patients with Parkinson's disease (PD) were compared. Twenty-seven patients suffered from marked akinesia and rigidity (AR-type) and 18 patients from predominant resting tremor (T-type). Dementia, depression, and psychosis occurred in 26, 18, and 18 patients, respectively. Neuronal counts were performed in defined areas of the medial and lateral substantia nigra (SNM, SNL), locus ceruleus (LC), and dorsal raphe nucleus (DRN). The AR-type (compared with the T-type) showed higher neuronal loss of LC, SNL, SNM, and more severe gliosis, extraneuronal melanin deposits, and neuroaxonal dystrophy in substantia nigra. Demented PD patients showed more intense cortical Alzheimer lesions and higher neuronal depletion in the SNM, whereas PD subjects with moderate or marked dementia differed from mildly or not demented ones only in the higher degree of cortical Alzheimer lesions. More severe neuronal cell loss of DRN was observed in PD patients with depression. Occurrence of psychosis was not associated with any pathologic feature. Our findings indicate that some major clinical features of PD are related to distinct neuropathologic lesions.
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PMID:The neuropathologic basis of different clinical subgroups of Parkinson's disease. 174 81

Neuronal loss in the substantia nigra (SN) in Parkinson's disease (PD) shows a topographical organisation where the lateral part of the SN is more affected. This is--due to projection of the lateral SN mainly to the putamen--reflected in more complete loss of dopamine content in the putamen than in the caudate nucleus. Of the parkinsonian symptoms rigidity and hypokinesia are associated with neuronal loss in the lateral substantia nigra and the resulting dopamine loss in the putamen. Neuronal mechanisms other than degeneration of the nigrostriatal system seem to be involved in the pathophysiology of tremor. Cognitive impairment and dementia in PD is related to dysfunction of the cortical cholinergic system, especially in the frontal cortex. The brain dopaminergic system, however, contributes as a subcortical component to cognitive impairment in PD. Clinical studies have shown that selegiline may slow down the progression of PD. We studied postmortem samples of patients treated with selegiline and levodopa and those with levodopa alone. The number of medial nigral neurons was significantly higher in the selegiline group. Treatment with selegiline might retard the death of nigral neurons, but further studies are needed to confirm the preliminary findings.
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PMID:Nigral degeneration in Parkinson's disease in relation to clinical features. 180 43

Gray tremor (gt) is an autosomal recessive mutation mapped to chromosome 15 in the mouse. Its phenotypic feature most relevant to human disease is a noninflammatory spongiform encephalopathy which has been transmitted to genetically normal mice in a previously reported, preliminary inoculation experiment. The present study describes the histopathology, topography, developmental sequence, and ultrastructure of the inherited spongiform encephalopathy in the gray tremor homozygote (gt/gt). Vacuolation is present in the first postnatal week in spinal and cerebellar white matter, and spreads rapidly by the second postnatal month to involve gray and white matter throughout almost the entire neuraxis. Adjacent swollen and vacuolated neuronal processes, particularly dendrites, appear to coalesce to form membrane-bound vacuoles in the neuropil. Neuronal abnormalities include focal distension of intracellular membranes and distension, fragmentation, bleb formation, rupture, and disintegration of plasma membranes. White matter vacuoles result from splitting of the myelin sheath at the intraperiod line and from vesicle formation in oligodendroglial inner loop cytoplasm. These ultrastructural abnormalities targeted on subcellular and cellular membranes in neurons and oligodendrocytes implicate a membrane disorder as a fundamental component of the pathogenetic mechanism. A comparison of the pathology of gt to that caused by unconventional agents and neurotropic retroviruses suggests that gt may be valuable in conceptually unifying the whole class of noninflammatory spongiform lesions.
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PMID:Pathology of the spongiform encephalopathy in the Gray tremor mutant mouse. 351 79

We report a 75-year-old man with parkinsonism who died suddenly. The patient was well until 64 years of the age when he had an onset of tremor in his left hand. He was treated with a medicine in another hospital, and his tremor subsided. Five years after the onset, he started to note difficulty in fine finger movements and gait disturbance. He tended to lean backward with frequent falls. He was treated with bromocriptine, trihexyphenydil, and L-dops without apparent improvement. He visited our out patient clinic on November 11, 1993 when he was 75 years of the age. Neurologic examination at that time revealed an alert and well oriented man in no acute distress. Higher cerebral functions were intact. In the cranial nerves, he showed restriction in the upward as well as down ward gaze (40% of normal). He showed masking of the face and spoke in small voice. He walked in a stooped posture with small steps; retropulsion was present. Muscle rigidity was moderately positive in the neck, however, no rigidity was noted in the limbs. No abnormal involuntary movements were seen. He showed moderate bradykinesia and difficulty in finger tapping. Muscle stretch reflexes were normally elicited and the plantar response was flexor bilaterally. Sensation was intact. The autonomic nervous system appeared intact. He was treated with 300 mg/day of Sinemet with marginal improvement in his balance. In February 4, 1994, he had a common cold. On the next day, his parkinsonism worsened and he became unable to walk by himself. He was found unconscious in the bathroom on the same day. He was brought to our hospital by an ambulance. Upon arrival, he was unresponsive and was not breathing. Blood pressure could not be measured. Pupils were dilated without reaction to light. Cardiac resuscitation was attempted, however, ventricular fibrillation appeared on an EEG monitor, and he was pronounced dead at eleven o'clock in the morning. The patient was discussed in a neurological CPC, and the chief discussant arrived at the conclusion that the patient had progressive supranuclear palsy because of vertical gaze palsy, axial rigidity, and poor response to levodopa. Regarding the cause of his sudden death, the chief discussant thought that he developed pulmonary embolism. Postmortem examination revealed non-bacterial thrombotic endocarditis in the heart, but this did not appeared to be related to his sudden death. Multiple disseminated small emboli were found occluding small arteries of the left lung; this was consistent with acute pulmonary embolism, and this was thought to be the cause of his sudden death. In the central nervous system, marked atrophy of the globus pallidus was noted; both internal as well as external segments showed marked atrophy; no myelinated fibers were seen in the globus pallidus. Neuronal cell loss was marked in the globus pallidus, the subthalamic nucleus, and the substantia nigra. No Lewy bodies or tangles were seen. The histologic diagnosis was consistent with pallido-nigro-luysian atrophy. Brownish pigments such as seen in Hallervorden-Spatz disease were seen in the globus pallidus. In addition, formy spheroids were seen in the substantia nigra. However, iron deposits were not so strong as to suggest Hallervorden-Spatz disease. Pallido-nigro-luysian atrophy is a rare neurodegenerative disorder. It is interesting to note that this condition may mimic progressive supranuclear palsy or pure akinesia clinically.
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PMID:[A 75-year-old man with parkinsonism and sudden death]. 853 59

Tremors were observed in 15 Long Evans rats beginning at 10 to 12 days of age. These were followed by progressively worsening ataxia, hind limb paresis, episodes of immobility, and seizures by 5 to 14 weeks. Gross lesions were not observed at necropsy in rats euthanized and perfused at 4 to 16 weeks of age. Neurohistologic examination revealed dysmyelination in the central nervous system. Astrogliosis in the white matter with marked increase of expression of the glial fibrillary acid protein marker was accompanied by diffuse microgliosis. Scattered glial cells, interpreted to be oligodendrocytes, contained minute periodic acid-Schiff-positive cytoplasmic granules. Large mineralized periodic acid-Schiff-positive and laminated structures were observed in the cerebellar white matter, midbrain, and thalamus of rats over 6 weeks old. Neuronal degeneration and loss was evident in the cortex, hippocampus, and midbrain. Large axonal spheroids were found in the ventral and lateral funiculi of the spinal cord. An ultrastructural study of four affected rats revealed an almost complete absence of myelinated axons and normal sheaths, and degeneration and necrosis of oligodendrocytes. The Long Evans shaker rat represents a novel myelin mutant with a remarkable survival period and appears to have an autosomal recessive mode of inheritance.
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PMID:Familial dysmyelination in a Long Evans rat mutant. 856 54

Microrecordings were performed during pallidotomy and thalamotomy for Parkinson's disease (PD). Neuronal activity in globus pallidus (GP) was in general agreement with previous studies of human and primate models of PD. Neuronal activity, where frequency of tremor appeared to oscillate independently from peripheral input, was encountered in GPi. In contrast, neuronal activity in Vim regarding frequency of firing also correlated with tremor and was passively driven by kinesthetic stimuli with a somatotopic arrangement. Pallidal lesions based on microrecording induced relative reductions of tremor, while small Vim lesions immediately alleviated tremor. Basal ganglia pathology due to dopamine depletion could generate oscillatory neuronal activity in GPi, which may cause tremor. However, peripheral feedback to the motor cortex via Vim is also significant for tremorgenesis, because Vim may be an excitatory driving source for motor cortical neurons. Thus, a Vim lesion could reduce excitability of the motor cortical neurons and abolish tremor.
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PMID:Neuronal activity in GP and Vim of parkinsonian patients and clinical changes of tremor through surgical interventions. 1007 70

Domoic acid (Dom) is a glutamate analog and a seafood toxin that has caused neurological disturbance and death in humans. Brain lesions caused by Dom have been documented in the literature, but the effect of Dom on the spinal cord has not been investigated as extensively. Systemic administration of glutamate agonists (i.e., homocysteate, kainate, and a-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) caused spinal cord lesions in infant rats. In the present study, the toxic effects of Dom on the developing spinal cord are examined. Neonatal rats on Postnatal Day 7 were administered Dom subcutaneously at doses of 0.10, 0.17, 0.25, 0.33, 0.42, and 0.50 mg/kg, respectively. Motor seizures characterized by scratching, tail flicking, and swimming-like movement were induced by Dom at all doses. High doses of Dom (> or = 0.33 mg/kg) further induced a hindlimb paralysis, a forelimb tremor, and death that occurred in less than 2 hours. The percentages of death and paralysis induced by 0.33 mg/kg Dom were 47% and 65%, respectively (n = 17). At this dose, electrocorticogram was recorded and synchronized interrupted electrical activities in brains of these animals were detected. However, no brain damage was detected in these rats. Spinal cord lesions characterized by focal hemorrhage, neuronal swelling, and neuronal vacuolization were found in 73% of the animals that had shown the paralysis/tremor in their extremities, as examined 1 to 2 hours after Dom injection. These lesions were seen at all spinal cord levels. Neuronal degeneration was mainly found in the ventral and intermediate gray matter, whereas cells in the dorsal portion of the spinal cord were relatively spared. Data suggest that observed behavioral changes were due to spinal cord damage rather than seizures or brain lesions.
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PMID:Systemic administration of domoic acid-induced spinal cord lesions in neonatal rats. 1075 72

Frontotemporal dementia and Parkinsonism linked to chromosome 17 (FTDP-17) are related to pathogenic mutations of the Tau gene. One of these, located at codon 279, results in an asparagine to lysine substitution. It was detected in three unrelated families from different origins. This mutation affects splicing, allowing exon 10 to be incorporated more frequently in the Tau transcripts, causing an abnormal preponderance of three-over four-repeat isoforms in soluble tau and the presence of the four-repeat isoforms in the insoluble tau. To better understand this newly described pathology, we analysed data from the three previously reported families. The American family, described as "pallido-ponto-nigral degeneration" is a large family which has been extensively studied (13 neuropathological studies). The Japanese family was initially presented as "pallidonigroluysian degeneration with iron deposition" and recently found to be related to N279 K mutation. We reported clinical, pathological and genetic data from the French family. Clinical particularities are ocular movements alterations with vertical supranuclear palsy, extrapyramidal signs (rigidity, dyskinesia, with atypical resting and postural tremor) and progressive dementia. Partial or no L-DOPA responsiveness is noted. These features led to discuss progressive supranuclear palsy, in some cases. There is no amyotrophy, nor any sensibility to neuroleptics, both signs being observed in other FTDP-17 syndromes. Neuropathology and immunohistochemistry confirm the presence of Tau immunolabeled inclusions, affecting mainly neurons in brain stem nuclei and glial cells in supratentorial white matter. Neuronal loss, which is moderate in frontal and temporal cortex, is severe in substantia nigra and globus pallidum. It is variable in other subcortical structures. In these structures, it is associated with iron deposition. This latter may participate in the degenerative process of cells and led to death in some specific neurons. The selectivity of neuronal death in hereditary diseases, when compared to data concerning sporadic neurodegenerative diseases which share similar clinical signs and neuropathological lesions, reinforces the hypothesis of an increased vulnerability of some neuronal populations which express specific sets of tau isoforms. Neurons particularly involved in these diseases express exclusively exon 10 + tau isoforms.
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PMID:[Neurodegenerative disease associated with a mutation of codon 279 (N279K) in exon 10 of Tau protein]. 1098 64

Juvenile parkinsonism (onset age <20 yrs) is uncommon and few cases with neuropathologic confirmation have been reported. We present the case of a 17-year-old boy who presented with asymmetric arm tremor and bulbar symptoms. His paternal great aunt had parkinsonism with onset at age 22 years. Examination revealed parkinsonism in the absence of additional neurologic signs except for delayed pupillary responses to light. He responded well to levodopa but developed motor fluctuations and disabling dyskinesias after 3 years of treatment. Following attempted withdrawal of levodopa at age 24 years, he developed severe aspiration pneumonia complicated by cardiorepiratory arrests and he died 6 months later. At autopsy, the dominant histologic feature was wide-spread neuronal hyaline intranuclear inclusions. Neuronal depletion was observed in the substantia nigra, locus ceruleus, and, to a lesser extent, in the frontal cortex, and inclusions were particularly prominent in these areas. Inclusions were immunoreactive for ubiquitin and were typical of those seen in neuronal intranuclear inclusion disease (NIID), a rare, multisytem neurodegenerative disease. NIID should be considered in the differential diagnosis of juvenile parkinsonism. A link between NIID and hereditary neurodegenerative disorders characterized by expanded polyglutamine tracts is supported by the similar appearance of intranuclear inclusions in both conditions and by a family history in some cases of NIID.
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PMID:Neuronal intranuclear inclusion disease and juvenile parkinsonism. 1100 11

Dopamine depletion induces a series of changes in the basal ganglia motor circuit that underlie the origin of the cardinal features of Parkinson's disease. It has now been established that hyperactivity of the subthalamic nucleus (STN) is an essential feature of the parkinsonian state. This leads to increased excitatory driving onto the globus pallidum internum (GPi) and substantia nigra reticulata (SNr) which, in turn, overinhibits the motor projections to the thalamus and brainstem. The STN and GPi have become the preferred targets for surgery to treat PD. In keeping with the classic pathophysiologic model, physiologic and neuroimaging studies in patients have shown that lesioning or functional blockades (by deep brain stimulation, or DBS) of these nuclei increased cortical activation, in parallel with clinical improvements of bradykinesia. Neuronal recording during surgery has also shown tremor-related activity in both the STN and GPi. However, the pathophysiologic model of the basal ganglia needs further refinement to provide a more detailed explanation of the origin of both tremor and rigidity in Parkinson's disease and to explain the antidyskinetic effect of surgery of the GPi and STN.
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PMID:Pathophysiologic basis of surgery for Parkinson's disease. 1118 78


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